There is a strong connection between convexity and inequalities. So, techniques from each concept applies to the other due to the strong correlation between them; specifically, in the past few years. In this attempt, we consider the Hermite–Hadamard inequality and related inequalities for the class of functions whose absolute value of the third derivative are quasi-convex functions. Finally, the applications of our findings for special functions and particular functions are pointed out.
La desigualdad integral de Jensen tiene mucha importancia en cuanto a sus aplicaciones en diferentes campos de las matemáticas. En este artículo encontramos una nueva desigualdad tipo Jensen para funciones cuya segunda derivada en valor absoluto es $varphi$-convexa.
Highlighting patterns of distribution and assembly of plants involves the use of community phylogenetic analyses and complementary traditional taxonomic metrics. However, these patterns are often unknown or in dispute, particularly along elevational gradients, with studies finding different patterns based on elevation. We investigated how patterns of tree diversity and structure change along an elevation gradient using taxonomic and phylogenetic diversity metrics. We sampled 595 individuals (36 families; 53 genera; 88 species) across 15 plots along an elevational gradient (2440– 3330 m) in Ecuador. Seventy species were sequenced for the rbcL and matK gene regions to generate a phylogeny. Species richness, Shannon–Weaver diversity, Simpson’s Dominance, Simpson’s Evenness, phylogenetic diversity (PD), mean pairwise distance (MPD), and mean nearest taxon distance (MNTD) were evaluated for each plot. Values were correlated with elevation and standardized effect sizes (SES) of MPD and MNTD were generated, including and excluding tree fern species, for comparisons across elevation. Taxonomic and phylogenetic metrics found that species diversity decreases with elevation. We also found that overall the community has a non-random phylogenetic structure, dependent on the presence of tree ferns, with stronger phylogenetic clustering at high elevations. Combined, this evidence supports the ideas that tree ferns have converged with angiosperms to occupy the same habitat and that an increased filtering of clades has led to more closely related angiosperm species at higher elevations.
GLOBAL CHANGE BIOLOGYPublicación
Global change is impacting forests worldwide, threatening biodiversity and ecosystem services including climate regulation. Understanding how forests respond is critical to forest conservation and climate protection. This review describes an international network of 59 long-term forest dynamics research sites (CTFS-ForestGEO) useful for characterizing forest responses to global change. Within very large plots (median size 25 ha), all stems ≥1 cm diameter are identiﬁed to species, mapped, and regularly recensused according to standardized protocols. CTFS-ForestGEO spans 25°S–61°N latitude, is generally representative of the range of bioclimatic, edaphic, and topographic conditions experienced by forests worldwide, and is the only forest monitoring network that applies a standardized protocol to each of the world’s major forest biomes. Supplementary standardized measurements at subsets of the sites provide additional information on plants, animals, and ecosystem and environmental variables. CTFS-ForestGEO sites are experiencing multifaceted anthropogenic global change pressures including warming (average 0.61 °C), changes in precipitation (up to !30% change), atmospheric deposition of nitrogen and sulfur compounds (up to 3.8 g N m"2 yr"1 and 3.1 g S m"2 yr"1), and forest fragmentation in the surrounding landscape (up to 88% reduced tree cover within 5 km). The broad suite of measurements made at CTFS-ForestGEO sites makes it possible to investigate the complex ways in which global change is impacting forest dynamics.
The conservation of tropical forest carbon stocks offers the opportunity to curb climate change by reducing greenhouse gas emissions from deforestation and simultaneously conserve biodiversity. However, there has been considerable debate about the extent to which carbon stock conservation will provide benefits to biodiversity in part because whether forests that contain high carbon density in their aboveground biomass also contain high animal diversity is unknown. Here, we empirically examined medium to large bodied ground‐dwelling mammal and bird (hereafter “wildlife”) diversity and carbon stock levels within the tropics using camera trap and vegetation data from a pantropical network of sites. Specifically, we tested whether tropical forests that stored more carbon contained higher wildlife species richness, taxonomic diversity, and trait diversity. We found that carbon stocks were not a significant predictor for any of these three measures of diversity, which suggests that benefits for wildlife diversity will not be maximized unless wildlife diversity is explicitly taken into account; prioritizing carbon stocks alone will not necessarily meet biodiversity conservation goals. We recommend conservation planning that considers both objectives because there is the potential for more wildlife diversity and carbon stock conservation to be achieved for the same total budget if both objectives are pursued in tandem rather than independently. Tropical forests with low elevation variability and low tree density supported significantly higher wildlife diversity. These tropical forest characteristics may provide more affordable proxies of wildlife diversity for future multi‐objective conservation planning when fine scale data on wildlife are lacking.
Mapping aboveground carbon density in tropical forests can support CO2 emission monitoring and provide benefits for national resource management. Although LiDAR technology has been shown to be useful for assessing carbon density patterns, the accuracy and generality of calibrations of LiDAR-based aboveground carbon density (ACD) predictions with those obtained from field inventory techniques should be intensified in order to advance tropical forest carbon mapping. Here we present results from the application of a general ACD estimation model applied with small-footprint LiDAR data and field-based estimates of a 50-ha forest plot in Ecuador’s Yasuní National Park. Subplots used for calibration and validation of the general LiDAR equation were selected based on analysis of topographic position and spatial distribution of aboveground carbon stocks. The results showed that stratification of plot locations based on topography can improve the calibration and application of ACD estimation using airborne LiDAR (R 2 = 0.94, RMSE = 5.81 Mg¨ C¨ ha´1 , BIAS = 0.59). These results strongly suggest that a general LiDAR-based approach can be used for mapping aboveground carbon stocks in western lowland Amazonian forests.
Necrophilia in amphibians is a poorly known behaviour despite its potential as a beneficial adaptation for improving reproductive success. Here, we describe the observation of a multiple amplexus involving necrophilia in the recently described Tsachila snouted treefrog, Scinax tsachila (Anura: Hylidae). We further provide an extensive review of published necrophilia in amphibians. At least 33 species of amphibians, mostly anurans, have shown a necrophiliac behaviour, with only one case of necrophilia in a caudate. Necrophilia has long been considered a maladaptive behaviour, since reproduction is usually not viable and is also associated with increased risk of death. However, necrophiliac behaviour has recently been proposed as an adaptive behaviour for some species because it may result in viable offspring.
Microbiome–pathogen interactions are increasingly recognized as an important element of host immunity. While these host-level interactions will have consequences for community disease dynamics, the factors which influence host microbiomes at larger scales are poorly understood. We here describe landscape-scale pathogen–microbiome associations within the context of post-epizootic amphibian chytridiomycosis, adisease caused by the panzootic chytrid fungus Batrachochytrium dendrobatidis. We undertook a survey of Neotropical amphibians across altitudinal gradients in Ecuador~30 years following the observed amphibian declines and collected skin swab-sam-ples which were metabarcoded using both fungal (ITS-2) and bacterial (r16S) ampli-cons. The data revealed marked variation in patterns of both B. dendrobatidis infection and microbiome structure that are associated with host life history. Stream breeding amphibians were most likely to be infected with B. dendrobatidis. This increased probability of infection was further associated with increased abundance and diversity of non-Batrachochytrium chytrid fungi in the skin and environmental microbiome.We also show that increased alpha diversity and the relative abundance of fungi are lower in the skin microbiome of adult stream amphibians compared to adult pond breeding amphibians, an association not seen for bacteria. Finally, stream tadpoles exhibit lower proportions of predicted protective microbial taxa than pond tadpoles,suggesting reduced biotic resistance. Our analyses show that host breeding ecology strongly shapes pathogen–microbiome associations at a landscape scale, a trait that may influence resilience in the face of emerging infectious diseases.
AMPHIBIAN & REPTILE CONSERVATIONPublicación
The Andes have experienced an unprecedented wave of amphibian declines and extinctions that are linked to a combination of habitat reduction and the spread of the fungal pathogen, Batrachochytrium dendrobatidis (Bd). In the present study, a range of high-altitude habitats in Southern Ecuador were surveyed for the presence of Bd. With a particular focus on Yacuri National Park, infection data are presented from across the resident amphibian community. This community contains a once putatively extinct species which was rediscovered in 2016, the Podocarpus Stubfoot Toad (Atelopus podocarpus). Across species, local Bd prevalence was 73% in tadpoles (n = 41 individuals from three species) and 14% in adults (n = 43 individuals from 14 species). Strikingly, 93% (14/15) of tested tadpoles of the recently described local endemic, Gastrotheca yacuri, were infected with a high pathogen load, suggesting that this species likely acts as a reservoir of infection in Yacuri. These fndings show that the threat of disease for A. podocarpus still exists, and that this species requires urgent action to ensure its survival
BMC RESEARCH NOTESPublicación
Objective: Edema syndrome is highly prevalent but under researched in captive frogs around the world. The objective of the present study was to characterize at a basic microbiological and cytological level of the bacteria of the edema fuid of 20 individuals of the genus Gastrotheca to determine the presence of possible anaerobic and aerobic bacteria. Results: Fourteen types of bacteria were identified in the edema fuid, 12 of them at the species level (Pasteurella haemolytica, Hafnia alvei, Enterobacter agglomerans, Aeromonas hydrophila, Pseudomonas fuorescens, Burkholderia pseudomallei, Salmonella arizonae, Enterobacter gergoviae, Enterobacter sakazakii, Yersinia enterocolitica, Klebsiella oxytoca, and Klebsiella ozaenae) and two at the genus level (Enterococcus spp. and Streptococcus spp.). The most fre‑ quently identifed cells were lymphocytes (37.7% in females and 46.4% in males), erythrocytes (23.5% in females and 17.5% in males) and neutrophils (4.2% in females and 2.8% in males). Finally, no relationship was found between the data obtained and the sex of the individuals studied.
ADVANCES IN DIFFERENCE EQUATIONSPublicación
In this paper, we have established some generalized inequalities of Hermite–Hadamard–Fejér type for generalized integrals. The results obtained are applied for fractional integrals of various type and therefore contain some previous results reported in the literature
Aquanectria and Gliocladiopsis are two closely related genera of Hypocreales. They are also morphologically similar, forming hyaline, penicillate conidiophores and hyaline, straight to sinuous, 0–1-septate phialoconidia. During a revision of gliocladiopsis-like isolates originating from rain forest areas of South America (Ecuador, French Guiana) and Southeast Asia (Singapore), multilocus phylogenetic inferences, based on DNA sequences encoding partial β-tubulin (TUB2), translation elongation factor 1-α (TEF1- α), histone H3 (HIS3) genes and the nuc rDNA internal transcribed spacer region (ITS1-5.8S-ITS2 = ITS), revealed the occurrence of seven new phylogenetic species. These phylogenetic species also revealed unique combinations of phenotypes, allowing morphological distinction from their closest phylogenetic relatives. Four new species of Aquanectria and three new species of Gliocladiopsis are described and illustrated. Three of the four Aquanectria species deviate from the other species in the genus by having shorter conidia, which are in the size range observed in Gliocladiopsis species. They are placed in Aquanectria based on the phylogenetic analysis, but this also makes the morphological distinction between these two genera obsolete
Organic matter from slaughterhouses can be used through anaerobic digestion to produce biogas and a nutrient-rich fertilizer. Monitoring the concentration of methane, propane, and butane are relevant parameters that show the efficiency of digestion. In the present study, a methodology for the measurement of these hydrocarbons was developed, using Fourier transform infrared spectrophotometry (FTIR) and the assistance of chemical-quantum calculations, which allowed the assignment of absorption bands of each hydrocarbon in biogas. The quantification limits were 0.36 %V/V for propane and butane and 1.47 %V/V for methane. Digestion tests were carried out with waste from the municipal slaughter center of the Metropolitan District of Quito, obtaining that a mixture of rumen and bovine manure, subjected to 50 °C, generated enriched biogas up to 65.4 %V/V after 15 days of digestion. Additionally, solid and liquid digestate produced met with international regulations for possible application in the soil. The results demonstrate the potential of the digestion monitoring method and the possible transformation of litter waste into a renewable energy source.
El torrente de imágenes drásticas de las consecuencias tangibles de la acumulación de plásticos en los océanos es imparable; en Europa, desde hace algunas décadas, y en Ecuador, hace poco más de dos años. Todos los medios de comunicación tradicionales, redes sociales y nuevas tecnologías nos enfrentan continuamente a una realidad apabullante: dentro de nada tendremos más plásticos que peces en el mar y el 99% de las aves marinas habrá consumido y sufrido las consecuencias del plástico para 2050 . Nuestra actitud ante el plástico se queda corta. La falta de reciclaje no es sino uno de muchos problemas clave.
Detection of plastic debris degrading into micro particles across all oceanic environments and inside of marine organisms is no longer surprising news. Microplastic contamination now appears as one of the world’s environmental main concerns. To determine the levels of microplastic pollution at sea, water samples were collected across a 4000 km-trajectory in the Tropical Eastern Pacifc and the Galápagos archipelago, covering an area of 453,000 square kilometres. Furthermore, 240 specimens of 16 diferent species of fsh, squid, and shrimp, all of human consumption, were collected along the continental coast. Microplastic particles were found in 100% of the water samples and marine organisms. Microplastic particles ranging from 150 to 500 μm in size were the most predominant. This is one of the frst reports simultaneously detecting and quantifying microplastic particles abundance and their impact on marine organisms of this region.
Mutualistic relationships between organisms have long captivated biologists, and extrafloral nectaries, or nectar‐producing glands, found on many plants are a good example. The nectar produced from these glands provides food for ants, which may defend the plant from potential herbivores in turn. However, relatively little is known about their impact on the long‐term growth and survival of plants that produce them. To better understand the ecological significance of extrafloral nectaries, we examined their incidence on lowland tropical rain forest trees in Yasuní National Park in Amazonian Ecuador, and collated data from two other tropical lowland forest sites (Barro Colorado Island, Panamá and Pasoh Forest Reserve, Malaysia). At Yasuní, extrafloral nectaries were found on 137 of 1123 species censused (12.2%), widely distributed among different angiosperm families. This rate of incidence is high but consistent with other tropical locations. Furthermore, this study adds 18 new genera and two new families (Urticaceae and Caricaceae) to the list of taxa exhibiting extrafloral nectaries. Using demographic data from long‐term forest dynamics plots at each site, we compared the growth and mortality rates of species with extrafloral nectaries to those without. After controlling for phylogeny, no general relationship between extrafloral nectary presence and demographic rates could be detected, suggesting little demographic signal from any community‐wide ecological effects.
Objetivo: Determinar los mecanismos de resistencia antibiótica y la epidemiología molecular de aislados clínicos de Klebsiella pneumoniae resistentes a carbapenémicos. Materiales y métodos: 30 aislados multirresistentes de K. pneumoniae fueron obtenidos a partir de: urocultivo, aspirado traqueal, secreción de herida, sonda vesical, hemocultivo, líquido peritoneal, punta de catéter, colección abdominal y secreción bronquial. Los aislados fueron colectados de noviembre de 2012 a abril de 2013. La identificación y susceptibilidad antibiótica fue determinada por el sistema automatizado VITEK 2. Para la amplificación de genes de resistencia se empleó PCR, la determinación de las Secuencias Tipo (ST) fue obtenida por tipificación multilocus de secuencias (MLST) y la relación clonal fue establecida por electroforesis en gel de campo pulsado (PFGE). Resultados: Todos los aislados mostraron fenotipos multirresistentes, excepto a colistina y tigeciclina. El 100% de los aislados fue productor de la carbapenemasa KPC- 2. La determinación de la presencia de genes codificantes de β-lactamasas de Espectro Extendido mostró que el 67% de los aislados fue positivo para el gen blaCTX-M, el 100% fue positivo para el gen blaSHV y 93% fue positivo para el gen blaTEM. El análisis de la relación clonal de los 30 aislados agrupó a 20 en un mismo pulso tipo. El análisis por MLST demostró que la ST predominante fue ST258 presente en el 60% de la población, seguida de ST1199 presente en el 20% de la población analizada. Conclusiones: Los resultados obtenidos demuestran la importancia de implementar y combinar estudios pidemiológicos, clínicos y moleculares para comprender la distribución de la resistencia entre bacterias de interés clínico.
DISEÑO URBANO Y PAISAJEPublicación
El presente estudio muestra el rendimiento de un prototipo de jardín vertical activo “CMMC” como unidad de enfriamiento y filtro para mejorar la calidad del aire interior y exterior. El comportamiento de jardines verticales fue analizado mediante tres casos de estudio. El jardín vertical activo CMMC enfrió el aire en un promedio de 8,1 °C con una capacidad de enfriamiento promedio de 682,8 W. Incluyendo los efectos del preenfriamiento en la entrada del jardín, el jardín enfrió el aire 14,3 °C en promedio, con una capacidad de enfriamiento promedio de 1.203,2 W. En el tercer caso, se monitoreó la calidad del aire en las cercanías y en sitios sin la influencia del jardín vertical, logrando una disminución de ozono (75%), dióxido de nitrógeno (44%) y partículas PM2,5 (79%) y PM10 (85%). Los resultados fueron concluyentes: el jardín activo CMMC presenta mejoras de calidad del aire superiores respecto a los jardines pasivos. El fenómeno de absorción de contaminantes marca una propuesta para la mejora de la calidad del aire en zonas críticas de contaminación en el Centro Histórico de Quito.
Se estudió la contaminación del aire a filo de calle en el Centro Histórico de Quito (DMQ) en un punto de alto flujo vehicular mediante el monitoreo continuo de gases y material particulado entre el 5 y 12 de abril de 2018. Se obtuvieron los perfiles horarios de las concentraciones de contaminantes y se pudo explicar su comportamiento. Las mediciones en el estudio no sobrepasaron los límites permisibles nacionales ni internacionales de calidad del aire; sin embargo, se observaron picos anómalos en el caso del dióxido de azufre. Se evaluó la correlación cruzada de las series de tiempo entre los datos reportados por estaciones regionales de la Secretaria de Ambiente del DMQ y los datos obtenidos en este estudio, hallándose que el monóxido de carbono presenta una mayor concentración a filo de calle. Al realizar el análisis de componentes principales (ACP) se determinó varios contaminantes correlacionados, lo que corroboran sus ciclos de formación y demuestran la influencia de factores meteorológicos en la contaminación de aire a filo de calle. Finalmente se determinó que las concentraciones de PM10 en aire interior son mayores a lo registrado en aire exterior en el sitio de muestreo.
MEMORIAS DEL XXXVI CONGRESO INTERAMERICANO DE INGENIERIA SANITARIA Y AMBIENTAL, AIDIS, ECUADOR 2018Publicación
Air pollution on street level in one of high traffic zones of the Metropolitan District of Quito (DMQ) was studied between March 16 and 22 of 2018 by monitoring gases and particulate matter (PM) with continuous analyzers. During the monitoring period, there were no violations of the air quality environmental regulations; however, the carbon monoxide values obtained in this study were higher than those registered in the MQ Environment Secretariat regional monitoring stations. Time series analysis allowed to understand trends and behaviors of pollutants concentration throughout the day, as well as correlated associating parameters, such as ozone, nitrogen dioxide and PM which behaviors were influenced by the atmospheric conditions and DMQ anthropogenic activity. Additionally, indoors air PM concentration was determined to be higher similar tendency. Statistical analysis showed correlated parameters groups such as secondary pollutants, temperature and humidity that represented the most influential component. Pollutants concentration depend on day time as well as associated meteorological factors like humidity and temperature, demonstrating that DMQ pollution at street level was a unique study case to understand air pollution in high altitude cities.
REVISTA AMBIENTE E AGUAPublicación
Industrial development has made new products available to people to make their lives easier. Items such as food, cleaning, personal care and health products, among others, are processed, sold and consumed daily by all age groups. These products include in their formulation inorganic and organic chemicals with the purpose of improving or increasing some of their properties, making them more attractive to the consumer. These substances are strictly controlled during production so that the final product may be safely consumed. In most cases, the constituents of commercial products end up in wastewater, where they are not controlled. These uncontrolled pollutants of differing chemical natures are known as “ Emerging Contaminants ” (ECs). Research worldwide has found ECs in various environmental matrices, especially water . To understand this problem, four fundamental aspects must be addressed: 1) the analytical methods for its determination; 2) the occurrence in environmental matrices; 3) the treatments for the removal of ECs in wastewater and drinking water plants; and 4) the risks to health and the environment. This document reviews these four aspects with regard to 14 ECs commonly found in the studies around the world and addresses the state of these ECs in trans-American waters . © 2019, Institute for Environmental Research in Hydrographic Basins (IPABHi). All rights reserved.
JOURNAL OF WATER AND HEALTHPublicación
Chemical elements, which are present in drinking water, could vary due to water sources, treatment processes or even the plumbing materials. Most of these elements do not represent a threat, while others, such as heavy metals, have been proven to cause harmful effects over human and aquatic wildlife. In this study, the quality of drinking water in three cities in Ecuador, Quito, Ibarra and Guayaquil was assessed through a multielement analysis and the heavy metal pollution index (HPI). A total of 102 drinking water samples and six natural water samples were collected and analyzed. Within the scope of analysis, results show that water quality complies with local and international guidelines. HPI did not show significant differences in the water that is supplied to the different neighborhoods of the three cities studied. However, actions should be taken to protect the sources of water, especially in Guayaquil, due to the presence of lead and chromium. For instance, lead was found in 2.8% of the samples in concentrations above World Health Organization (WHO) recommended values. Thus, we suggest to assessing the quality and age of the plumbing system within the whole country, in order to avoid drinking water contamination with heavy metals.
JOURNAL OF MOLECULAR MODELINGPublicación
In this research, we present a preliminary computational study of four Dermaseptin-related peptides from the skin exudate of the gliding tree frog Agalychnis spurrelli. Experimentally, the amino acid sequence of these peptides was elucidated through molecular cloning and tandem mass spectrometry and synthetic peptides were assayed against E. coli, S. aureus, and C. albicans to determine their antimicrobial properties. With the sequences on hand, a computational study of the structures was carried out, obtaining their physicochemical properties, secondary structure, and their similarity to other known peptides. A molecular docking study of these peptides was also performed against cell membrane and several enzymes are known to be vital for the organisms. Results showed that Dermaseptin-related peptides are α-helical cationic peptides with an isoelectric point above 9.70 and a positive charge of physiological pH. Introducing theses peptides in a database, it was determined that their identity compared with known peptides range from 36 to 82% meaning these four Dermaseptins are novel peptides. This preliminary study of molecular docking suggests the mechanism of action of this peptide is not given by the inhibition of essential enzymatic pathways, but by cell lysis.
En esta investigación se presenta un estudio computacional de la dermaseptina SP2 (DRS-SP2) extraída de exudado de la piel de la rana Agalychnis spurrelli. Ensayos experimentales han permitido extraer, puri?car y obtener la secuencia de aminoácidos de este péptido, además de demostrar sus propiedades antimicrobianas contra Escherichia coli, Staphylococcus aureus y Candida albicans. Con la secuencia dilucidada, se realizó un estudio computacional de la estructura obteniéndose sus propiedades físicoquímicas, su estructura secundaria y su similitud con otros péptidos conocidos. Además,se realizó el acoplamiento molecular de este péptido con la membrana celular y varias enzimas conocidas para suprimir a estos microorganismos. Los resultados muestran que la DRS-SP2 es un péptido catiónico α-helicoidal con un punto isoeléctrico de 10,68 y carga positiva +3 a pH ?siológico. Se determinó que su estructura es diferente a todas las dermaseptinas que se encuentran en bases de datos llegando a un porcentaje de identidad máximo del 80 %. Estudios de acoplamiento molecular sugieren que el mecanismo de acción de este péptido no se da por la inhibición de vías enzimáticas vitales para el microorganismo, sino por lisis celular.
NEW ZEALAND JOURNAL OF MATHEMATICSPublicación
We show a necessary and sufficient condition for any ordinal number to be a Polish space. We also prove that for each countable Polish space, there exists a countable ordinal number that is an upper bound for the first component of the Cantor-Bendixson characteristic of every compact countable subset of the aforementioned space. In addition, for any uncountable Polish space, for every countable ordinal number and for all nonzero natural number, we show the existence of a compact countable subset of this space such that its Cantor-Bendixson characteristic equals the previous pair of numbers. Finally, for each Polish space, we determine the cardinality of the partition, up to homeomorphisms, of the set of all compact countable subsets of the aforesaid space.
AUSTRALIAN JOURNAL OF MATHEMATICAL ANALYSIS AND APPLICATIONSPublicación
We show in detail that every compact countable subset of a metric space is homeomorphic to a countable ordinal number, which extends a result given by Mazurkiewicz and Sierpinski for finite-dimensional Euclidean spaces. In order to achieve this goal, we use Transfinite Induction to construct a specific homeomorphism. In addition, we prove that for all metric space, the cardinality of the set of all the equivalence classes, up to homeomorphisms, of compact countable subsets of this metric space is less than or equal to aleph-one. We also show that for all cardinal number smaller than or equal to aleph-one, there exists a metric space with cardinality equals the aforementioned cardinal number.
Los ecosistemas se¬cos son el punto de reunión de un gran número de especies que tienen una larga historia que contar; sobre cómo los ani¬males y plantas se resistieron a cam¬biar cuando los grandes colosos se levantaron e impusieron un nuevo régimen de humedad, temperatura y precipitación. Muchas familias botánicas fueron separadas unas de otras y tuvieron la oportunidad de diversificarse, llenando diversos nichos en el nuevo ecosistema. A los científicos les gusta darle a esta historia el nombre de evolución; di-lucidarla nos permite comprender la intrincada relación que existe entre los distintos miembros que constru¬yen la gran familia de la vida a lo largo del tiempo. Con estas pala¬bras queremos contar la historia de los bosques secos en el Ecuador, sus amenazas y estado de conservación, cómo es su diversidad y endemis¬mo a nivel regional, de manera que ayude a entender los procesos que los hacen ecosistemas “solitarios”, incluso cuando se encuentran ro¬deados por páramos, bosques mon¬tanos y amazónicos.
Background: Conserving both biodiversity and ecosystem services is a major goal of the Convention on Biological Diversity. Hotspots for biodiversity in the Andes significantly overlap with areas with dense human populations that sustain their economy through agricultural production. Therefore, developing management forms that reconcile food provisioning services—such as agriculture—with biodiversity conservation must be addressed to avoid social conflicts and to improve conservation in areas where biodiversity co-occurs with other ecosystem services. Here, we present a high-resolution conservation plan for vascular plants and agriculture in the Ecuadorian Dry Inter-Andean Valleys (DIAV) hotspot. Trade-offs in conserving important areas for both biodiversity and agriculture were explored. Methods: We used a dataset containing 5,685 presence records for 95 plant species occurring in DIAVs, of which 14 species were endemic. We developed habitat suitability maps for the 95 species using Maxent. Prioritization analyses were carried out using a conservation planning framework. We developed three conservation scenarios that selected important areas for: biodiversity only, agriculture only, and for both biodiversity and agriculture combined.
PLANTS, PEOPLE, PLANETPublicación
Understanding of tropical forests has been revolutionised by monitoring in permanent plots. Data from global plot networks have transformed our knowledge of forests’ diversity, function, contribution to global biogeochemical cycles, and sensitivity to climate change. Monitoring has thus far been concentrated in rain forests. Despite increasing appreciation of their threatened status, biodiversity, and importance to the global carbon cycle, monitoring in tropical dry forests is still in its infancy. We provide a protocol for permanent monitoring plots in tropical dry forests. Expanding monitoring into dry biomes is critical for overcoming the linked challenges of climate change, land use change, and the biodiversity crisis.
Frog skin secretions contain medically-valuable molecules, which are useful for the discovery of new biopharmaceuticals. The peptide profile of the skin secretion of Agalychnis spurrelli has not been investigated; therefore, the structural and biological characterization of its compounds signify an inestimable opportunity to acquire new biologically-active chemical scaffolds. In this work, skin secretion from this amphibian was analysed by molecular cloning and tandem mass spectrometry. Although the extent of this work was not exhaustive, eleven skin secretion peptides belonging to five peptide families were identified. Among these, we report the occurrence of two phyllokinins, and one medusin-SP which were previously reported in other related species. In addition, eight novel peptides were identified, including four dermaseptins, DRS-SP2 to DRS-SP5, one phylloseptin-SP1, and three orphan peptides. Phylloseptin-SP1 and dermaseptins-SP2 were identified in HPLC fractions based on their molecular masses determined by MALDI-TOF MS. Among the antimicrobial peptides, dermaseptin-SP2 was the most potent, inhibiting Escherichia coli, Staphylococcus aureus, and ORSA with a minimum inhibitory concentration (MIC) of 2.68 μM, and Candida albicans with an MIC of 10.71 μM, without haemolytic effects. The peptides described in this study represent but a superficial glance at the considerable structural diversity of bioactive peptides produced in the skin secretion of A. spurrelli.
EUROPEAN JOURNAL OF TAXONOMYPublicación
Five new species of the genus Drosophila Fallén, 1823 belonging to the tripunctata group are described and illustrated: D. warmi sp. nov., D. kurillakta sp. nov., D. chichu sp. nov., D. saraguru sp. nov. and D. ayauma sp. nov. from the forests of Podocarpus National Park. The first species is ascribed to subgroup II of Frota-Pessoa (1954), the second species to subgroup IV, and the last three species are not assigned to any subgroup. The flies were captured using plastic bottles containing pieces of yeast fermented banana.
Five species of the genus Drosophila are described and illustrated: D. zamorana sp. n., D. quinarensis sp. n.,D. sachapuyu sp. n., D. caxarumi sp. n., and D. misi sp. n. from the cloud forests of the Podocarpus National Park, in the southern Ecuadorian Andes. Flies were captured using plastic bottles containing pieces of fermented banana with yeast. All the species were found to belong to the Drosophila guarani species-group.
REVISTA ECUATORIANA DE MEDICINA Y CIENCIAS BIOLÓGICAS (REMCB)Publicación
Ocho nuevas especies del género Drosophila fueron descritas e ilustradas: Drosophila kingmani sp. nov., Drosophila malacatus sp. nov., Drosophila millmasapa sp. nov., Drosophila pichka sp. nov., Drosophila rusaryu sp. nov., Drosophila shunku sp. nov., Drosophila shunkuku sp. nov. y Drosophila taki sp. nov. Las especies fueron colectadas en los bosques nublados del Parque Nacional Podocarpus en los Andes del sur de Ecuador. Las moscas fueron capturadas usando botellas plásticas cebadas con pedazos de banana fermentados con levadura.
The Stripe-headed Round-eared bat, Tona_a saurophila, includes three subspecies: Tona_a saurophila saurophila (known only from subfossil rec saurophila bakeri (distributed from southeastern Mexico to northern Colombia, Venezuela west and north of the Cordillera de Mérida, and northwest saurophila maresi (distributed in Venezuela east and south of the Cordillera de Mérida, the Guianas, Trinidad and Tobago, northeastern Brazil, and alon in Colombia, Ecuador, Peru, and Bolivia). The last two subspecies are an a_rac_ve example to test predic_ons about the historical role of the Andes in m Based on morphological descrip_ons, morphometric analyses, and phylogene_c reconstruc_on using the mitochondrial gene Cyt-b and the nucle evaluates the intraspecific rela_onships within Tona_a saurophila and the taxonomic status of the taxon. The three subspecies of T. saurophila are reTona_a bakeri, Tona_a maresi, and Tona_a saurophila. The la_er is restricted to its type locality and possibly is ex_nct. Tona_a bakeri, in addi_on to be morphologically dis_nguishable by possessing an acute apex at the posterior edge of the skull, a well-developed clinoid process, and rela_vely robust by lacking a diastema between the canine and the first lower premolar. The gene_c distance between T. bakeri and T. maresi is 7.65%.
ECOLOGY AND EVOLUTIONPublicación
The conspecific negative density dependence hypothesis states that mortality of young trees (seedlings and saplings) is higher near conspecific adults due to mechanisms such as allelopathy, intraspecific competition, and pest facilitation, explaining why in the tropics, most of plant species tend to be rare and live dispersed. However, there are some tree species that defy this expectation and grow in large clusters of conspecific juveniles and adults. We hypothesize that conspecifics living in clusters show higher and/or more variable defensive profiles than conspecifics with dispersed distributions. We evaluated our hypothesis by assessing the expression of physical leaf traits (thickness, and the resistance to punch, tear and shear) and leaf chemical defenses for six clustered and six non‐clustered tree species in Yasuní National Park, Ecuadorian Amazon. We ask ourselves whether (a) clustered species have leaves with higher physical resistance to damage and more chemical defenses variability than non‐clustered species; (b) saplings of clustered species may show higher physical resistance to damage and higher variation on chemical leaf defenses than their conspecific adults, and (c) saplings of non‐clustered species show lower resistance to physical damage and lower variation in chemical defenses compared to conspecific adults. Overall, our study did not support any of our hypotheses. Remarkably, we found that soluble metabolites were significantly species‐specific.
Quantifying the relative contributions of plant physicochemical traits and environmental conditions to leaf decomposition is essential to increase our understanding of ecosystem processes in forested terrestrial and aquatic habitats. This is particularly crucial in tropical rainforests that display high levels of tree diversity and environmental heterogeneity over relatively small spatial scales. For example, in Amazonia, detritus from hundreds of tree species fuels carbon cycling in watersheds, but much remains to be learned about how species traits interact with environmental conditions to mediate decomposition. We investigated the leaf-litter decomposition of 17 tree species with contrasting traits in soil and stream habitats in Yasuni National Park, Ecuador. We hypothesized that (1) habitat type would be the major determinant of leaf decomposition (faster in stream than soil systems), (2) species would be ranked similarly in terms of leaf decomposition rates, according to decomposability traits (i.e., litter quality), within each habitat, and (3) the variability of leaf decomposition within habitats would be greater for soil than for stream systems. Contrary to our first hypothesis, we found that leaf-litter decomposition rates for any given tree species were similar in stream and soil systems. However, we found that the relative importance of litter traits for decomposition such as concentrations of micronutrients (Mn and Cu, in particular) was consistent across habitats.
PLOS NEGLECTED TROPICAL DISEASESPublicación
Although a century has elapsed since Chagas disease discovery, only two drugs, benznida-zole and nifurtimox, are approved for its treatment. These drugs have significant safety and efficacy limitations and their specific modes of action are still poorly understood. Moreover, the causative agent, the protozoan parasite Trypanosoma cruzi, displays high genetic variability, which is suspected to affect clinical manifestations and disease out-come. With these facts in mind, we aimed to elucidate the role of the parasite’s genetic background in benznidazole treatment efficacy. Our results unveiled interesting differ-ences in the sensitivity to benznidazole between some T. cruzi genotypes, which suggests genetic variability could influence patient cure rates. Additionally, they show the need for uniformity in experimental conditions during laboratory analysis of new drug candidates for Chagas disease treatment, and they highlight the importance of screening diverse T.cruzi strains from different genetic background as part of the process of drug evaluation and optimization.
Current rates of biodiversity loss pose an unprecedented challenge to the conservation community, particularly with amphibians and freshwater fish as the most threatened vertebrates. An increasing number of environmental challenges, including habitat loss, pathogens, and global warming, demand a global response toward the sustainable management of ecosystems and their biodiversity. Conservation Breeding Programs (CBPs) are needed for the sustainable management of amphibian species threatened with extinction. CBPs support species survival while increasing public awareness and political influence. Current CBPs only cater for 10% of the almost 500 amphibian species in need. However, the use of sperm storage to increase efficiency and reliability, along with an increased number of CBPs, offer the potential to significantly reduce species loss. The establishment and refinement of techniques over the last two decades, for the collection and storage of amphibian spermatozoa, gives confidence for their use in CBPs and other biotechnical applications. Cryopreserved spermatozoa has produced breeding pairs of frogs and salamanders and the stage is set for Lifecycle Proof of Concept Programs that use cryopreserved sperm in CBPs along with repopulation, supplementation, and translocation programs. The application of cryopreserved sperm in CBPs, is complimentary to but separate from archival gene banking and general cell and tissue storage. However, where appropriate amphibian sperm banking should be integrated into other global biobanking projects, especially those for fish, and those that include the use of cryopreserved material for genomics and other research.
The family of mosquitoes (Diptera: Culicidae) contains several species of major public health relevance due to their role as vectors of human disease. One of these species, Aedes aegypti, is responsible for the transmission of some of the most important vector-borne viruses affecting humankind, including dengue fever, chikungunya and Zika. Traditionally, control of Ae. aegypti and other arthropod species has relied on the use of a relatively small diversity of chemical insecticides. However, widespread and intensive use of these substances has caused significant adverse environmental effects and has contributed to the appearance of pesticide-resistant populations in an increasing number of locations around the world, thereby dramatically reducing their efficiency. Therefore, it becomes urgent to develop novel alternative tools for vector control. In that context, our study aimed at evaluating the insecticidal activity against Ae. aegypti of aqueous extracts obtained from the fruits of Solanum mammosum L., as well as silver nanoparticles synthesized using aqueous extracts from this plant species (SmAgNPs). To perform the test, third instar Ae. aegypti larvae were exposed to increasing concentrations of plant extract and SmAgNPs for 24 h. Our results suggest that both the aqueous extract and SmAgNPs were toxic to the larvae, with SmAgNPs displaying a much higher level of toxicity than the extract alone, as reflected in their LC50 values (0.06 ppm vs 1631.27 ppm, respectively).
Se han descrito muchos estudios de biosíntesis de nanopartículas de plata usando el extracto del bulbo de ajo (Allium sativum) como agente reductor. Sin embargo, el uso de sus hojas es poco conocido, por considerarse un producto de desecho. En este estudio, se comparó el tamaño de nanopartículas de plata obtenidas con el extracto acuoso de las hojas de ajo usando dos técnicas diferentes de calentamiento: placa y por microondas. Las nanopartículas obtenidas se caracterizaron por espectrofotometría UV-Visible, microscopía de transmisión electrónica (TEM, por sus siglas en inglés), dispersión dinámica de luz (DLS, por sus siglas en inglés) y difracción de rayos X (XRD, por sus siglas en inglés). Como resultado se obtuvieron nanopartículas con un tamaño promedio de 15,4±7,9 y 9,9±10,5 nm empleando las dos técnicas respectivamente. De acuerdo al análisis estadístico realizado, se demostró que existen diferencias significativas en relación al tamaño de nanopartícula obtenido. Se concluye que el extracto acuoso de las hojas de la planta de ajo, es un agente reductor adecuado para la síntesis de nanopartículas de plata, y que la técnica de microondas es más efectiva por la rapidez y tamaño de nanopartículas obtenidas.
REGIONAL ENVIRONMENTAL CHANGEPublicación
The high tropical Andes are rapidly changing due to climate change, leading to strong biotic community, ecosystem, and landscape transformations. While a wealth of glacier, water resource, and ecosystem-related research exists, an integrated perspective on the drivers and processes of glacier, landscape, and biota dynamics is currently missing. Here, we address this gap by presenting an interdisciplinary review that analyzes past, current, and potential future evidence on climate and glacier driven changes in landscape, ecosystem and biota at different spatial scales. We first review documented glacier changes and landscape evolution over past decades to millennia and analyze projected future glacier shrinkage until 2100 for two case studies in the tropical Andes. The effects of climate and glacier change on high Andean biota are then examined from paleoecological research and comparative gradient analyses to chronosequence and diachronic studies of vegetation dynamics. Our analysis indicates major twenty-first century landscape transformations with important socioecological implications which can be grouped into (i) formation of new lakes and drying of existing lakes as glaciers recede, (ii) alteration of hydrological dynamics in glacier-fed streams and high Andean wetlands, resulting in community composition changes, (iii) upward shifts of species and formation of new communities in deglaciated forefronts,(iv) potential loss of wetland ecosystems, and (v) eventual loss of alpine biota. We advocate strengthening an interdisciplinary research agenda with a strong policy formulation link that enables enhanced cross-sectorial cooperation and knowledge sharing, capacity building of relevant stakeholders, and a more active participation of both government agencies and social organizations.
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICAPublicación
Alexander von Humboldt’s Tableau Physique (1807) has been one of the most influential diagrams in the history of environmental sciences. In particular, detailed observations of the altitudinal distribution of plant species in the equatorial Andes, depicted on a cross-section of Mt. Chimborazo, allowed Humboldt to establish the concept of vegetation belt, thereby laying the foundations of biogeography. Surprisingly, Humboldt’s original data have never been critically revisited, probably due to the difficulty of gathering and interpreting dispersed archives. By unearthing and analyzing overlooked historical documents, we show that the top section of the Tableau Physique, above the tree line, is an intuitive construct based on unverified and therefore partly false field data that Humboldt constantly tried to revise in subsequent publications. This finding has implications for the documentation of climate change effects in the tropical Andes. We found that Humboldt’s primary plant data above tree line were mostly collected on Mt. Antisana, not Chimborazo, which allows a comparison with current records. Our resurvey at Mt. Antisana revealed a 215- to 266-m altitudinal shift over 215 y. This estimate is about twice lower than previous estimates for the region but is consistent with the 10- to 12-m/decade upslope range shift observed worldwide. Our results show the cautious approach needed to interpret historical data and to use them as a resource for documenting environmental changes. They also profoundly renew our understanding of Humboldt’s scientific thinking, methods, and modern relevance.
JOURNAL OF ECOLOGYPublicación
Dispersal is a key ecological process that influences plant community assembly. Therefore, understanding whether dispersal strategies are associated with climate is of utmost importance, particularly in areas greatly exposed to climate change. We examined alpine plant communities located in the mountain summits of the tropical Andes across a 4,000-km latitudinal gradient. We investigated species dispersal strategies and tested their association with climatic conditions and their evolutionary history. We used dispersal-related traits (dispersal mode and growth form) to characterize dispersal strategies for 486 species recorded on 49 mountain summits. Then we analysed the phylogenetic signal of traits and investigated the association between dispersal traits, phylogeny, climate and space using structural equation modelling and fourth-corner analysis together with RLQ ordination.
FORENSIC SCIENCE INTERNATIONAL: GENETICS SUPPLEMENT SERIESPublicación
Chytrid fungi and viruses within the genus Ranavirus have been associated with mass mortality events and declines in amphibian populations worldwide. The fungus Batrachochytrium dendrobatidis (Bd) was reported in Ecuador; however, other chytrid fungi like Batrachochytrium salamandrivorans (Bsal) or ranaviruses have not been described in the country so far. To prevent the introduction of pathogens into amphibian populations under conservation programs and to implement a successful disease surveillance program, the development of a sensitive and specific diagnostic assay was required. We describe here the optimization of one TaqMan probe-based multiplex quantitative polymerase chain reaction (qPCR) assay that enables the simultaneous detection of Bsal and ranavirus, and one monoplex TaqMan qPCR assay for the detection of Bd. Standard curves, with a high linear correlation (r2 > 0.995), were generated using a synthetic genome template (gBlocks®) containing the target sequences from all three pathogens. Different samples from skin, liver, kidney, spleen, and lung from six different amphibian species were tested, and both qPCR assays showed highly reproducible and reliable results. To our knowledge, this method is the first multiplex qPCR system developed in Ecuador for identifying amphibian pathogens and represents a valuable tool for the early detection of these pathogens and for infection and co-infection monitoring in future epidemiological surveillance of amphibian species at risk of extinction.
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICAPublicación
Reply to Morueta-Holme et al.: Humboldt’s historical data are not messy, they just need expert examination
JOURNAL OF BIOGEOGRAPHYPublicación
Methods: Temperature data for 505 vascular plant species from alpine communities on 49 summits, were extracted from 29,627 georeferenced occurrences. Species thermal niche traits (TNTs) were estimated using bootstrapping for: minimum temperature, opti‐ mum (mean)temperature and breadth (maximum‐minimum). Plant community‐weighted scores were estimated using the TNTs of their constituent species. CVH was tested for species, biogeographical species groups and communities. Vulnerability to global warm‐ ing was assessed for species, biogeographical species groups and communities. Results: Species restricted to the equator showed narrower thermal niche breadth than species whose ranges stretch far from the equator, however, no difference in niche breadth was found across summits’ elevation. Biogeographical species groups distributed close to the equator and restricted to alpine regions showed narrower niche breadth than those with broader ranges. Community‐weighted scores of ther‐ mal niche breadth were positively related to distance from equator but not to el‐ evation. Based on their TNTs, species restricted to equatorial latitudes and plant communities dominated by these species were identified as the most vulnerable to the projected 1.5°C warming, due to a potentially higher risk of losing thermal niche space. Main conclusions: Our study confirms that the CVH applies to high tropical Andean plant species and communities, where latitude has a strong effect on the thermal niche breadth. TNTs are identified as suitable indicators of species’ vulnerability to warming and are suggested to be included in long‐term biodiversity monitoring in the Andes.
Heavy metals such as cadmium (Cd) are a global concern; recent researches have concluded that they are related to health risks caused by contaminated food intake. Although Cd contents in cocoa beans and their derivatives have been investigated, the relationship of Cd concentration with other metals such as nickel (Ni) and lead (Pb) information is not available. Thus, this study uses a general approach to examine Cd, Ni, and Pb concentrations in cocoa beans from nine Ecuadorian provinces. It aims to determine a possible relationship between each metal content. As results, Ni was the most abundant reaching concentrations between 1.462 and 8.528 mg kg−1 (mean 3.930 mg kg−1), followed by Pb between 0.502 and 1.966 mg kg−1 (mean 1.432 mg kg−1) and Cd between 0.267 and 1.715 mg kg−1 (mean 0.753 mg kg−1). The regression analysis results (< 0.2420746), the Pearson correlation coefficient values (< 0.369) and variation inflation factors results (< 1.319) do not demonstrate linear correlation or multivariate regression between each metal tested, thus it is not necessary to consider competition regarding metal intake by plants to develop successful remediation techniques. Nevertheless, the high values obtained should be considered by public health and commerce authorities for establishing permissible levels of Ni and Pb.
Environmental pollution allows heavy metals to interact with ecosystems, bioaccumulating and passing through the food chain. Animals and humans can consume contaminated species and reach toxic and harmful concentrations in their organisms. While there are international regulatory frameworks for heavy metal contents, these are not always known or suitable for local conditions. This situation calls for the development of locally-applicable analytical methods for the determination of heavy metal concentrations in common vegetal and animal food products. Two established methods (AOAC 999.11, based on sample drying and calcination, and IPN AC-06-00, based on microwave-assisted acid digestion) were comparatively tested at the CESAQ-PUCE laboratory in Quito, Ecuador, to determine their suitability. Sample matrices used were non-industrial, non-organic tomato, lettuce, and beef commonly found in local markets. Heavy metals tested were cadmium, nickel, and lead. Test guidelines and comparative parameters were based on AOAC (2002) and included quantification limits, repeatability variation coefficients, intermediate precision percentages, accuracy and calculated expanded uncertainties. Unlike method AOAC 999.11, method IPN AC-06-00 performance for all parameters was within the range of recommended expected values as per AOAC, and was therefore deemed more suitable to be applied under the local CESAQ-PUCE laboratory conditions. The validation of method IPN AC-06-00 demonstrated its local applicability. In addition, IPN AC-06-00 can be used by similar laboratories to assess contaminants concentrations and improve the baseline information concerning human exposure to toxic metals.
In this study, cadmium (Cd), nickel (Ni), and lead (Pb) contents were analyzed in sixteen banana composite samples from different commercial establishments from eleven Ecuadorian production provinces using graphite furnace atomic absorption spectrophotometry. The concentrations (fresh weight) in the samples collected (9.3-47.3 μg·kg for Cd, 16.1-105.6 μg·kg for Ni, and 36.9-538.0 μg·kg for Pb) were used to calculate the estimated daily intake (EDI), target hazard quotient (THQ), and target carcinogenic risk (CR) associated with dietary exposure to these potentially toxic metals. Cd and Ni results showed that every sample had EDIs lower than the oral reference dose and THQ values lower than 1, demonstrating that there was no non-carcinogenic risk related to the exposure to Cd and Ni. In the case of Pb, two EDIs results were higher than the reference dose, also their corresponding THQ values were higher than 1. The lead CR in all samples was less than 1 × 10 , the upper limit used for acceptable cancer risk. Thus, there is no significant health risk to the consumer associated with bananas with contamination levels of Cd, Ni, but there is Pb risk for toddlers (12 kg of body weight) intake comparable to the one detected in the present study.
CRITICAL REVIEWS IN ENVIRONMENTAL SCIENCE AND TECHNOLOGYPublicación
Glyphosate is the most widely used active ingredient of Glyphosate Based Herbicides (GBHs), and which has environmental mobility towards water by its physicochemical characteristics. These properties determine its low availability in living organisms (log Kow < 0), which is increased by the presence of co-adjuvant activators in GBHs and its biodegradation (metabolites). Eco-toxicological studies have determined that glyphosate affects to several aquatic trophic-levels (freshwater/marine environments), being more toxics GBHs. Therefore, its potential environmental risk has promoted the development of conventional (biological and physicochemical) and non-conventional (Advanced-Oxidation-Processes or AOPs, combined processes) treatment strategies. Biological processes will generate incomplete degradation (metabolites generation), and variable removal efficiencies (25–99%). Physicochemical processes will be efficient (approx. 90%) but transferring the glyphosate from water to the adsorbent material (dangerous waste generation). Currently, AOPs will arise as a rapid (minutes) and effective alternative for glyphosate removal (>90%), depending on operational conditions, and without generation of intermediate metabolites. Moreover, new strategies (electrochemical) will avoid the hazardous waste production. Other combined processes (biological physicochemical) will also reach glyphosate efficiencies removal above 90% but needing large spaces. However, their physical characteristics would make them feasible to be applied in agricultural areas.
Los policloruros de bifenilo (PCB’s) son compuestos orgánicos que fueron usados en condensadores y transformadores eléctricos debido a sus propiedades aislantes y alta estabilidad química. Al prohibirse la fabricación y el uso de PCB’s, gran cantidad de estos equipos eléctricos quedaron obsoletos y enormes volúmenes de aceite dieléctrico con PCB’s se almacenaron como desecho peligroso a la espera de una alternativa para su eliminación. En este trabajo se reporta la transferencia de fase del Aroclor 1254, desde el aceite dieléctrico hacia fase acuosa, para su posterior degradación fotocatalítica. Se probaron dos agentes de transferencia de fase, Polietilenglicol 400 y Tritón X-100. El proceso fotocatalítico se llevó a cabo con TiO2 sin irradiar (0 kGy) e irradiado con haz de electrones a dosis de 20 y 60 kGy, se utilizó radiación ultravioleta como fuente de energía durante la fotodegradación. La degradación se siguió por cromatografía de gases y la mineralización se verificó mediante Carbono Orgánico Total (COT). La mayor eficiencia de transferencia de fase se logró con el Tritón X- 100, por lo que se utilizó este agente en los estudios posteriores. Los mejores resultados de degradación y mineralización del Aroclor 1254, se alcanzó con el TiO2 irradiado a 20 kGy, estos fueron de 98,36 % y 58,92 % respectivamente, luego de 240 min de fotooxidación. De esta manera esta tecnología se convierte en una alternativa viable para solucionar el problema de la contaminación por PCBs.
Long-term cadmium intake can be very dangerous to human health due to its toxic effects. Although people can be contaminated with this element from different sources, contaminated food is probably the most important one. Foods such as vegetables and fruits can become contaminated with cadmium existing in soils, irrigation water, or chemical fertilizers. Some plants produce an excess of cysteine-rich peptides (CRp) when affected by high concentrations of heavy metals such as cadmium, thus indicating the presence of this type of contamination. Among these plants is tamarillo (Solanum betaceum), which is locally known as “tree tomato”. This is a native plant widely consumed in the Ecuadorian Andes because of its abundance, low cost, and high content of vitamin C and fiber. The fact that Solanum betaceum produces CRp upon contamination with heavy metals means that this plant may be able to accumulate heavy metals. If this is the case, the plant can possibly be used as an indicator of metal pollution. The main goals of the present work were to evaluate the possibility of using Solanum betaceum as an indicator of metal contamination in plants and to examine its capability to accumulate metals. Both goals were met by determination of the amounts of CRp produced by Solanum betaceum cells cultivated in vitro in the laboratory under controlled conditions in the presence of different concentrations of cadmium. The CRp determination was carried out by means of electrogeneration of iodine in an iodide solution containing reduced glutathione as a biological thiol model. Solanum betaceum cells were grown in a Murashige and Skoog solution enriched with a 30 g L−1 sugar aqueous solution and 1 mg L−1 2,4-dichlorophenoxyacetic acid. The results of these experiments confirmed the following: (1) CRp production is a function of the amount of cadmium present as a contaminant up to a limiting value after which cell apoptosis occurs; (2) Solanum betaceum accumulates cadmium; (3) the analytical method used is appropriate for CRp determination; and (4) CRp determination is a valid alternative to detect contamination by heavy metals in plants.
The construction of a photoanode with several layers of titanium oxysulfate as a precursor to form ti- tanium dioxide-TiO2 on boron doped diamond-BDD (TiO2/BDD), and its application for the photoelectro-degradation of glyphosate in aqueous medium are presented. The study was divided into three stages: i) optimization of the number of layers of the TiO2 precursor to modify BDD using a novel method combining Sol-gel/Spin-Coating; ii) characterization of the TiO2/BDD electrodes, by scanning electron microscopy-SEM, dispersive energy spectroscopy-EDX, Ray diffraction-XRD, contact angle, and electro-chemical response by cyclic voltammetry using [Fe(CN)6] 3-/4- system; iii) degradation of glyphosate (50 mg L1) by electrochemical oxidation on BDD and photoelectrocatalysis on TiO2/BDD in dark and UV-light conditions, at different current densities, for 5 h. The glyphosate degradation and mineralization were evaluated by High-Performance Liquid Chromatography, Total Organic Carbon, Chemical Oxygen Demand and inorganic-ions concentration (NO3, PO3, and NH4þ). Also, the aminomethylphosphonicacid-AMPA was quantified by HPLC, as a degradation intermediate. Using five layers of the TiO2 pre-cursor, in the construction of TiO2/BDD photoanode, and a lower contact angle, greater photo-electrocatalysis against the [Fe(CN)6]3-/4- redox system and better degradation of glyphosate compared to BDD without modification were achieved. The formation of TiO2 nanoparticles (14.79 ± 3.43 nm) inanatase phase on BDD was verified by SEM and XRD. Additionally, glyphosate degradation and mineralization were 2.3 times faster by photoelectrocatalysis on TiO2/BDD, relative to BDD, at 3 mA cm2 and UV-light. Thus, the presence of TiO2 on BDD increases the rate and efficiency of glyphosate degra-dation with respect to electrochemical oxidation on BDD.
JOURNAL OF VOLCANOLOGY AND GEOTHERMAL RESEARCHPublicación
We use infrasound waves generated during eruptions of Volcán Tungurahua (Ecuador) to study both, changing atmospheric conditions and volcanic source characteristics. Analyzed infrasound data were recorded for a 32- month period by a five-station network located within 6.5 km from the vent. We use cross-network correlation to quantify the recurrent eruptive behavior of Tungurahua and results are corroborated by reports from the Ecuadorian monitoring agency. Cross-network lag times vary over short time periods (minutes to days) when vent location is stable and attribute these variations to changes in atmospheric structure. Assuming a fixed source location, we invert for average air temperatures and winds in Tungurahua's vicinity (b6.5 km) and find evidence for diurnal and semidiurnal tropospheric tides. We also use cross-network correlation lag times to compute infrasound source positions with resolutions of ~11.6 m, taking into account coarse NOAA atmospheric models for local winds and temperatures. Variable infrasound-derived source locations suggest source migration during the 32 months of analyzed data. Such source position variability is expected following energetic eruptions that destructively altered the crater/vent morphology as confirmed by imagery obtained during regular overflights.
PROCEEDINGS OF MEETINGS ON ACOUSTICSPublicación
As part of the Acoustic Surveillance for Hazardous Eruptions project, two infrasound arrays were installed in northern and central Ecuador. The RIOE and LITE arrays were operational between 2006 and 2013, recording thousands of infrasound signals originating from eruptions of Tungurahua, El Reventador, and Sangay. We use Progressive Multi-Channel Correlation array processing together with hierarchical clustering to identify and associate impulsive infrasound signals with each volcano. Infrasound detections correspond to quasi-continuous activity of Sangay between mid 2006 and mid 2012, at least thirteen periods of activity of Tungurahua between 2006 and mid 2012, and strong signals from El Reventador in early 2008. We validate our detections using satellite observations from the MODIS (Moderate Resolution Imaging Spectroradiometer) volcano detection algorithm (MODVOLC) and independent eruption catalogs. For Sangay, we find a good agreement between our infrasound detections and MODVOLC triggers, whereas for El Reventador the agreement is fair. We attribute the fair correspondence at El Reventador to the low-temporal resolution of MODIS data and frequent cloud cover in the region that reduce satellite observational capability. Finally, our study highlights the benefits of infrasound arrays for monitoring volcanoes in Ecuador at regional distances, while further investigating the processes that limit volcanic infrasound detection..
JOURNAL OF GEOPHYSICAL RESEARCH: SOLID EARTHPublicación
Seismic and infrasound multistation ambient-noise interferometry has been widely used to infer ground and atmospheric properties, and single-station and autocorrelation seismic interferometry has also shown potential for characterizing Earth structure at multiple scales. We extend autocorrelation seismic interferometry to ambient atmospheric infrasound recordings that contain persistent local noise from waterfalls and rivers. Across a range of geographic settings, we retrieve relative sound-speed changes that exhibit clear diurnal oscillations consistent with temperature and wind variations. We estimate ambient air temperatures from variations in relative sound speeds. The frequency band from 1 to 2 Hz appears most suitable to retrieve weather parameters as nearby waterfalls and rivers may act as continuous and vigorous sources of infrasound that help achieve convergence of coherent phases in the autocorrelation codas. This frequency band is also appropriate for local sound speed variations because it has infrasound with wavelengths of ∼170–340 m, corresponding to a typical atmospheric boundary layer height. After applying array analysis to autocorrelation functions derived from a three-element infrasound array, we find that autocorrelation codas are composed of waves reflected off nearby topographic features, such as caldera walls. Lastly, we demonstrate that autocorrelation infrasound interferometry offers the potential to study the atmosphere over at least several months and with a fine time resolution.
INTERNATIONAL JOURNAL OF GEOPHYSICSPublicación
Cotopaxi Volcano showed an increased activity since April 2015 and evolved into its eventual mild eruption in August 2015. In this work we use records from a broadband seismic station located at less than 4 km from the vent that encompass data from April to December of 2015, to detect and study low-frequency seismic events. We applied unsupervised learning schemes to group and identify possible premonitory low-frequency seismic families. To find these families we applied a two-stage process in which the events were first separated by their frequency content by applying the k-means algorithm to the spectral density vector of the signals and then were further separated by their waveform by applying Correntropy and Dynamic Time Warping. As a result, we found a particular family related to the volcano’s state of activity by exploring its time distribution and estimating its events’ locations.
GEOPHYSICAL RESEARCH LETTERSPublicación
We characterize and interpret a new type of infrasound signal originating from the summit of Volcán Cotopaxi (Ecuador) that was primarily observed between September 2015 and March 2016, following the 2015 eruptive period. This infrasound waveform is a slowly decaying sinusoid with exceptional low-frequency (fp = 0.2 Hz) and high quality factor (Q = ~10) and resembles the shape of tornillo seismic waveforms. The repeating events, occurring about once per day in early 2016, are stable in frequency content, and we attribute them to excitation of a vertical-walled crater, with radius of about 125 m and length of 300 m. Spectral properties of the tornillo permit constraints on crater sound speed (335 m/s ± 6%) and temperature (4–32°C). The initial polarity of the tornillos is predominantly a rarefaction and could reflect repeating crater bottom collapse events (implosions) or explosion sources whose infrasound is heavily modulated by the crater’s pipe-like geometry.
El proyecto “Caracterización y estadística de señales volcánicas en los Andes, casos de estudio volcanes Reventador y Cotopaxi en Ecuador” (GEOF 02 2019), formó parte del Programa de Asistencia Técnica del año 2019 del Instituto Panamericano de Geografía e Historia. Contempló trabajos de campo en el volcán Reventador en tres ocasiones, para descarga de datos y mantenimiento de las estaciones acústicas CON, LAV y AZU. Como parte de los trabajos de campo y de las discusiones científicas, se contó con la asistencia del doctor Jeffrey Johnson. También, se llevó a cabo el taller “Principios de Geofísica y Comunicación”, con la asistencia de 19 estudiantes de seis universidades, y siete instructores de diversas áreas de Ciencias de la Tierra. Adicionalmente, se hizo una consultoría para el desarrollo de un sistema de adquisición de datos acústicos, del cual ya se tienen los esquemas y reportes. Finalmente, se publicaron los resultados del proyecto en mayo de 2019, en la revista International Journal of Geophysics, igualmente se enviaron los resúmenes científicos a las conferencias: Fall Meeting 2019-American Geophysical Union, 8th International Symposium on Andean Geodynamics y al 1er Congreso de la Asociación Latinoamericana de Volcanología.
Many plant species exhibit strong association with topographic habitats at local scales. However, the historical biogeographic and physiological drivers of habitat specialization are still poorly understood, and there is a need for relatively easy-to-measure predictors of species habitat niche breadth. Here, we explore whether species geographic range, climatic envelope, or intraspecific variability in leaf traits is related to the degree of habitat specialization in a hyperdiverse tropical tree community in Amazonian Ecuador. Contrary to our expectations, we find no effect of the size of species geographic ranges, the diversity of climate a species experiences across its range, or intraspecific variability in leaf traits in predicting topographic habitat association in the ~300 most common tropical tree species in a 25-ha tropical forest plot. In addition, there was no phylogenetic signal to habitat specialization. We conclude that species geographic range size, climatic niche breadth, and intraspecific variability in leaf traits fail to capture the habitat specialization patterns observed in this highly diverse tropical forest.
JOURNAL OF TROPICAL ECOLOGYPublicación
Herbaceous plants are often under-studied in tropical forests, despite their high density and diversity, and little is known about the factors that influence their distribution at microscales. In a 25-ha plot in lowland Amazonian rain forest in Yasuní National Park, Ecuador, we censused six species of Heliconia (Heliconiaceae) in a stratified random manner across three topographic habitat types. We observed distribution patterns consistent with habitat filtering. Overall, more individuals occurred in the valley (N = 979) and slope (N = 847) compared with the ridge (N = 571) habitat. At the species level, Heliconia stricta (N = 1135), H. spathocircinata (N = 309) and H. ortotricha (N = 36) all had higher abundance in the valley and slope than ridge. Further, H. vellerigera (N = 20) was completely absent from the ridge. Conversely, H. velutina (N = 903) was most common in the drier ridge habitat. The two most common species (H. stricta and H. velutina) had a reciprocal or negative co-occurrence pattern and occurred preferentially in valley versus ridge habitats. These results suggest that taxa within this family have different adaptations to the wetter valley versus the drier ridge and that habitat partitioning contributes to coexistence.
A hydrogen peroxide (H2O2) sensor and biosensor based on modified multi-walled carbon nanotubes (CNTs) with titanium dioxide (TiO2) nanostructures was designed and evaluated. The construction of the sensor was performed using a glassy carbon (GC) modified electrode with a TiO2-CNT film and Prussian blue (PB) as an electrocalatyzer. The same sensor was also employed as the basis for H2O2 biosensor construction through further modification with horseradish peroxidase (HRP) immobilized at the TiO2-fCNT film. Functionalized CNTs (fCNTs) and modified TiO2-fCNTs were characterized by Transmission Electron Microscopy (TEM), Fourier Transform Infrared Spectroscopy (FTIR), and X-Ray DifFraction (XRD), confirming the presence of anatase over the fCNTs. Depending on the surface charge, a solvent which optimizes the CNT dispersion was selected: dimethyl formamide (DMF) for fCNTs and sodium dodecylsulfate (SDS) for TiO2-fCNTs. Calculated values for the electron transfer rate constant (ks) were 0.027 s-1 at the PB-fCNT/GC modified electrode and 4.7 × 10-4 s-1 at the PB-TiO2/fCNT/GC electrode, suggesting that, at the PB-TiO2/fCNT/GC modified electrode, the electronic transfer was improved. According to these results, the PB-fCNT/GC electrode exhibited better Detection Limit (LD) and Quantification Limit (LQ) than the PB-TiO2/fCNT/GC electrode for H2O2. However, the PB film was very unstable at the potentials used. Therefore, the PB-TiO2/fCNT/GC modified electrode was considered the best for H2O2 detection in terms of operability. Cyclic Voltammetry (CV) behaviors of the HRP-TiO2/fCNT/GC modified electrodes before and after the chronoamperometric test for H2O2, suggest the high stability of the enzymatic electrode. In comparison with other HRP/fCNT-based electrochemical biosensors previously described in the literature, the HRP-fCNTs/GC modified electrode did not show an electroanalytical response toward H2O2.
We modified and evaluated the performance of a CuO/Cu electrochemical electrode for chemical oxygen demand (COD) determination by covering it with a Nafion (Nf) film. The resulting modified CuONf/Cu electrode sensor was used for the electrochemical determination of COD in river, slaughterhouse and estuarine water samples in order to evaluate its performance for this particular task. It was compared with the CuO/Cu sensor with no Nafion. The main electrochemical characteristics of interest, resistance, sensitivity, accuracy and reproducibility, were assessed by means of Linear Sweep Voltammetry using glucose as a standard. Results of these essays indicate that the procedure used produced smooth and firmly attached Nf films covering the whole copper surface. This sensor was shown to be resistant to interferences and effective in electro-oxidation of a wide range of organic compounds and therefore very useful for COD determination. Using the newly developed CuONf/Cu electrode an analytical linear range of 50 to 1000 mg·L−1 COD, with a detection limit of 2.11 mg·L−1 (n = 6) COD was achieved. The comparison shows that the CuONf/Cu sensor is more appropriate for COD determination than its counterpart with no Nafion.
We report on two new electrochemical sensors which, coupled to differential pulse voltammetry, constitutes a useful tool for diagnosis of heavy metal pollution. The electrochemical sensors AgHgNf/Cu and the AgBiNf/Cu were obtained by deposition of bimetallic particles of AgHg or AgBi on copper electrodes covered with a Nafion (Nf) film, respectively. Micrographs of the electrode’s surface showed evenly scattered bimetallic particles, with an approximate diameter of 150 nm, embedded in the Nafion (Nf) film. In order to test the electrodes, the hydrogen evolution signal according to the Brdiˇcka reaction was measured for the determination of cysteine-rich peptides (CRp) produced by plants. To check the accuracy of the electrodes, real samples of Nicotiana tabacum cells exposed to cytotoxic levels of cadmium were tested. The AgHgNf/Cu electrode produced detection limits (DLs) of 0.088 µmol L−1 for Cysteine and 0.139µmol L−1 for Glutathione, while for the AgBiNf/Cu electrode DLs were 0.41 µmol L−1 for cysteine and 0.244 µmol L−1 for glutathione. Thus, the new electrodes could be a useful analytical electrochemical system very convenient for fieldwork. The electrodes were capable of direct, accurate, and sensitive detection of synthesized peptides, despite the complex matrix where the Nicotiana tabacum cells were grown
Lead ion in drinking water is one of the most dangerous metals. It affects several systems, such as the nervous, gastrointestinal, reproductive, renal, and cardiovascular systems. Adsorption process is used as a technology that can solve this problem through suitable composites. The adsorption of lead (Pb(II)) on graphene oxide (GO) and on two goethite (α-FeOOH)/reduced graphene oxide (rGO) composites (composite 1: 0.10 g GO: 22.22 g α-FeOOH and composite 2: 0.10 g GO: 5.56 g α-FeOOH), in aqueous medium, was studied. The GO was synthesized from a commercial pencil lead. Composites 1 and 2 were prepared from GO and ferrous sulfate. The GO and both composites were characterized by using scanning electron microscopy (SEM), scanning transmission electron microscopy (STEM), Raman spectroscopy, X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), and dynamic light scattering (DLS). The adsorption capacity of Pb(II) on the GO and both composites was evaluated through adsorption isotherms. Composite 1 presented a significant agglomeration of α-FeOOH nanorods on the reduced graphene oxide layers. Meanwhile, composite 2 exhibited a more uniform distribution of nanorods. The adsorption of Pb(II) on the three adsorbents fits the Langmuir isotherm, with an adsorption capacity of 277.78 mg/g for composite 2200 mg/g for GO and 138.89 mg/g for composite 1. Composite 2 emerged as a highly efficient alternative to purify water contaminated with Pb(II).
Presentamos la evaluación de los electrodos de carbono vítreo (GC) modificados con películas de Nafion (Nf) y depósitos bimetálicos de aleaciones Ag-Hg y Ag-Bi. La mayoría de los bimetálicos depositados, con un tamaño promedio de aproximadamente 150 nm, se dispersaron e incrustaron uniformemente dentro de la red del Nafion, mientras que una cantidad mucho menor permaneció encima de las incrustadas sin ninguna orientación regular, como lo indica imágenes de microscopía electrónica de barrido (SEM) y microscopía de fuerza atómica (AFM). Las pruebas de sensibilidad para el electrodo modificado AgBiNf/GC produjeron límites de detección (DL), basados en la variabilidad de una solución en blanco (criterio de 3 s), de 0,78 y 0,66 μg L-1 para Cd (II) y Pb (II), respectivamente; mientras que el DL sobre el electrodo modificado AgHgNf/GC fue 0,17 y 0,24 μg L-1 para Cd (II) y Pb (II), respectivamente. La precisión de la metodología por voltametría de redisolución anódica se verificó mediante el cálculo de porcentajes de recuperación de los dos analitos, expresados como error relativo. Se logró una recuperación del 99% al 92%.
LIBRO: HORSERADISH PEROXIDASE: STRUCTURE, FUNCTIONS AND APPLICATIONSPublicación
This chapter aims to cover the latest advancements and innovations in the field of enzymatic electrochemical sensors based on the electrical communication between “Horseradish Peroxidase” and the enzyme’s modified electrodes surfaces. The “Horseradish Peroxidase” is a glycoprotein that contains an iron porphyrin as an electroactive center that has been widely used as electrochemical biosensors due to its low cost and stable characteristics. Studies on the electrochemical behavior of a bioactive molecule as “Horseradish Peroxidase” have become one of the fastest growing fields, where interest has grown in biomedical engineering and biotechnology in the manufacture of more stable, responsive, accurate and voltammetric/amperometric biosensors. The application of this type of devices involves many fields: cancer diagnosis, water analysis, heavy metal ion detection, and toxicity detection. However, research on the electrochemical communication of redox enzyme immobilized on solid electrodes is one of the principal challenges for the development of electronic applications. This has opened a new route towards bioelectrochemical devices based on enzymes and metallic electrodes that demands more advanced and reliable tools. It includes an appropriate enzyme redox-electrode interface, where an appropriate “matrix” immobilization is essential to study and optimize the electrochemical properties of this kind of devices. This field presents a rapid growth in the design of this type of biosensors that have required the incorporation of nanomaterials. This document presents a review of the research that has been carried out in the development of nanomaterials for the fabrication of enzymes electrochemical sensors that have presented major efficiency for the immobilization and effective communication of “Horseradish Peroxidase” with the electrodic surface and its application for the precise detection of different important analytes (Peroxides, phenolic compounds and nitrides). In this review, the general voltammetric techniques are addressed and how these techniques are useful for the biosensitivity and detection of these devices, together with the important details and concepts around them, such as sensitivity and detection limits. The discussion gives a perspective of future concepts that can be used in the manufacture of sensors that involve the “Horseradish Peroxidase”, as well as the restrictions of the nanomaterials proposed and how their detection can be improved.
PLOS NEGLECTED TROPICAL DISEASESPublicación
Background Human transmission of Chagas disease (CD) most commonly occurs in domiciliary spaces where triatomines remain hidden to feed on blood sources during inhabitants’ sleep. Similar to other neglected tropical diseases (NTDs), sustainable control of CD requires attention to the structural conditions of life of populations at risk, in this case, the conditions of their living environments. Considering socio-cultural and political dynamics involved in dwellings’ construction, this study aimed to explore social factors that contribute or limit sustainability of CD’s prevention models focused on home improvement. Methods and main findings Using Healthy Homes for Healthy Living (HHHL)—a health promotion strategy focused on improvement of living environments and system-based health promotion—as a reference, a qualitative study was conducted. Research participants were selected from three rural communities of a CD endemic region in southern Ecuador involved in HHHL’s refurbishment and reconstruction interventions between.
REVISTA DE MATEMATICAS: TEORIA Y APLICACIONESPublicación
En el presente trabajo se encuentran resultados concernientes a la desigualdad integral de Hermite-Hadamard, y otras relacionadas con esta, usando funciones η−convexas y el operador integral fraccional definido por R.K. Raina.
En este artículo se estudia el carácter oscilatorio de una ecuación diferencial generalizada de orden α con α ∈ (0, 1]. se botienen criterios generalizados tipo Kamenev que son extensiones de resultados conocidos de la literatura para el caso tanto entero como fraccionario
APPLIED MATHEMATICS AND INFORMATION SCIENCESPublicación
Using the notion of s-ϕ-convex functions as generalization of convex functions, we estimate the difference between the middle and right terms in Hermite- Hadamard-Fejer inequality for differentiable mappings.
APPLIED MATHEMATICS AND INFORMATION SCIENCESPublicación
In the present work we introduce the class of (s,m)-convex functions on the coordinates and some new Ostrowski-type inequalities are deduced for this kind of generalized convex functions. The results obtained have the absolute value of the second partial derivative with respect to the coordinates (∂ 2 f /∂r∂t) in the aforementioned class and bounded, as a necessary condition. This generalizes the results for convex functions of . Also, some corollary is presented.
In the present work the Hermite-Hadamard inequality is established in the setting of quantum calculus for a generalized class of convex functions depending on three parameters: a number in (0, 1] and two arbitrary real functions defined on [0, 1]. From the proven results, various inequalities of the same type are deduced for other types of generalized convex functions. Also, the definition of dominated convex functions respect to the generalized class of convex functions aforementioned is introduced, and some integral inequalities are established.
En este artículo se estudia la dinámica de las soluciones de la ecuación de Hutchinson con retardo finito y como consecuencia se presenta una nueva prueba del Teorema de los números primos.
En este artículo establecemos algunos nuevos resultados relacionados a desigualdades del tipo Hermite-Hadamard para funciones cuya segunda derivada es s − ϕ−convexa.
APPLIED MATHEMATICS AND INFORMATION SCIENCESPublicación
In this paper we introduce the notion of s−j−convex functions as generalization of convex functions. Some basic results under various conditions for the function j are investigated. Moreover, we establish Ostrowski type inequalities for twice differentiable mappings which are s−j−convex.
APPLIED MATHEMATICS AND INFORMATION SCIENCESPublicación
In recent years, new classes of convex functions have been introduced in order to generalize the results and to obtain new estimations. In this paper, we give generalization of the Jensen’s inequality by using definition of convex functions on n–coordinates. Results given in  are particular cases of results given here.
Lanthanide-based optical nanothermometers, operating in the physiological temperature range (288–323 K), with excitation and emission in the first biological transparent window have special interest for biological applications. In this context, trivalent europium doped titanium oxide (Eu3þ:TiO2) nanoparticles were prepared via a sol-gel method and their spectroscopic properties were studied. In order to assess their potential for temperature sensing, excitation and luminescence spectroscopies were performed. We observed that the intensities of the excitation bands for the 7F0→5D0 (576 nm) and 7F2→5D0 (610 nm) transitions, monitoring the 5D0→7F4 (700nm) transition have a strong dependence on temperature. This dependence, which is explained in terms of a thermal coupling between the Eu3þ:7FJ levels, was used for the construction of an optical nanothermometer. Relative sensitivity values between 1.78 and 1.41% K? 1, when the temperature of the material increases from 288 to 323 K, were obtained. We show that the nanothermometer calibration can be obtained by a single luminescence room temperature measurement. Our results indicate the potential application of Eu3þ:TiO2 nanoparticles for temperature sensing in the first biological window and physiological temperature range.
Se presenta una propuesta para el ajuste empírico de curvas correspondientes a transiciones de fase en mediciones obtenidas por Análisis Térmico Diferencial (ATD). La familia de funciones que se plantean para el ajuste se conoce como funciones Gumbel; estas funciones tienen características de asimetría que se asemejan a las de los picos típicos de ATD, a diferencia de funciones simétricas usualmente utilizadas para el ajuste de picos, como Gaussianas o Lorentzianas. El proceso de ajuste se llevó a cabo con mediciones de ATD realizadas en muestras de compuestos InxMn(1-x)Sb, los cuales exhiben la presencia de dos fases; InSb y MnSb, en las que dependiendo del valor de x se observan transiciones de fase que pueden ser o no simultáneas en temperatura. Al trabajar con curvas de transiciones de fase individuales, las funciones de Gumbel ajustan las curvas con coeficientes de correlación lineal (R2) superiores a 0.98, tanto para transiciones de fusión como para transiciones de solidificación, lo que evidencia el correcto ajuste de los datos experimentales. Se demuestra la valía de este tipo de ajustes al ser empleados en un sistema donde existen transiciones de fase simultáneas en temperatura, en este caso se muestra cómo, con las funciones de Gumbel, es posible separar estas señales superpuestas. Una vez separadas se podría tener acceso a información como la temperatura de transición o a la entalpía de transformación de cada uno de los compuestos presentes en la mezcla, algo que actualmente es muy complicado de hacer para señales simultáneas de ATD.
En el artículo se presentan los principales resultados obtenidos durante el desarrollo de una investigación que definió como objetivo general “utilizar la Programación Lineal en Enteros (PLE) en la solución de problemas de corte de materiales en dos dimensiones (corte 2D) para piezas rectangulares”. Se utiliza una opción alternativa a las clásicas al abordar el problema a través de la implementación en el corte de variantes de sustitución (se consideran las piezas de mayor tamaño como si fueran también materia prima) definidas después como nuevas incógnitas en la modelación matemática de la situación en estudio para disminuir en general la cantidad de variables en el modelo. Se diseña e implementar un sistema informático (programa computacional que tiene implícito un algoritmo para la generación de variantes de corte 2D) que ejecuta el procesamiento matemático del modelo e interpreta de forma práctica los resultados obtenidos. También es presentado, a modo de ejemplo, una comparación entre la utilización de la opción propuesta y la vía heurística al resolver problemas de corte 2D. La propuesta presentada fue puesta en práctica en una empresa poligráfica, que en su proceso productivo está involucrada en el corte de piezas rectangulares de cartón, con resultados satisfactorios en el control de la producción y reducción significativa en los desperdicios de materia prima.
In 2014, a mammal survey was conducted in an ecotone region (including páramo and temperate forest) on the Eastern Versant of the Andes in Carchi province, Ecuador. Sherman traps, Tomahawk traps, pitfall traps, and mist nets were used to collect mammal specimens at two sites (3,340 m elevation and 3,650 m levation). A total of 142 specimens representing 14 species were collected from the survey area. Species collected include: Didelphis pernigra, Microryzomys altissimus, M. minutus, Nephelomys albigularis, Neusticomys monticolus, Reithrodontomys mexicanus soderstromi, Thomasomys baeops, T. cinnameus, T. vulcani, T. ucucha, Sturnira bidens, S. erythromos, and Myotis keaysi. One additional species (Mazama rufina) was documented by a partial skull salvaged from the forest near the biological station. A comparison of the effects of elevation on Ecuadorian rodent diversity was conducted by examining previous collections from this region.
El Plan de Acción para la Conservación de los Murciélagos del Ecuador fue presentado oficialmente el 17 de noviembre de 2015 luego de más de un año de trabajo colaborativo de especialistas ecuatorianos y extranjeros. El documento contó con el aval del Ministerio de Ambiente del Ecuador y con el apoyo financiero de la Pontificia Universidad Católica del Ecuador, Ecofondo y la Fundación Rufford. El 8 de agosto de 2016, mediante el Acuerdo Ministerial 084, el Plan de Acción fue reconocido como documento oficial del Estado Ecuatoriano. Actualmente, como parte de las actividades propuestas, se mantienen reuniones con la Comisión de Biodiversidad de la Asamblea Nacional del Ecuador para incluir a las Áreas y Sitios de Importancia para la Conservación de los Murciélagos dentro del Patrimonio de Áreas Protegidas del Estado. El documento reposa actualmente en las páginas de Internet del Programa para la Conservación de los Murciélagos del Ecuador y de la Red Latinoamericana para la Conservación de los Murciélagos y puede ser descargado libremente. El Plan de Acción es el segundo documento nacional de este tipo en Latinoamérica y se ha constituido en un ejemplo a seguir para otros Programas para la Conservación de los Murciélagos en la región
This study aims to analyze the thermal biology and climatic vulnerability of two closely related lizard species (Stenocercus festae and S. guentheri) inhabiting the Ecuadorian Andes at high altitudes. Four physiological parameters—body temperature (Tb), preferred temperature (Tpref), critical thermal maximum (CTmax), and critical thermal minimum (CTmin)—were evaluated to analyze the variation of thermophysiological traits among these populations that inhabit different environmental and altitudinal conditions. We also evaluate the availability of operative temperatures, warming tolerance, and thermal safety margin of each population to estimate their possible risks in the face of future raising temperatures. Similar to previous studies, our results suggest that some physiological traits (CTmax and Tb) are influenced by environmental heterogeneity, which brings changes on the thermoregulatory behavior. Other parameters (Tpref and CTmin), may be also influenced by phylogenetic constraints. Moreover, the fluctuating air temperature (Tair) as well as the operative temperatures (Te) showed that these lizards exploit a variety of thermal microenvironments, which may facilitate behavioral thermoregulation. Warming tolerance and thermal safety margin analyses suggest that both species find thermal refugia and remain active without reducing their performance or undergoing thermal stress within their habitats. We suggest that studies on the thermal biology of tropical Andean lizards living at high altitudes are extremely important as these environments exhibit a unique diversity of microclimates, which consequently result on particular thermophysiological adaptations.
In this work, the well-known Minkowski inequality is studied, using a generalized fractional integral operator, defined and studied by authors in a previous work. Relationships with known results are established throughout the work and in conclusions
Captive-bred organisms are widely used in ecology, evolution and conservation research, especially in scenarios where natural populations are scarce or at risk of extinction. Yet, it is still unclear whether captivity may alter thermal tolerances, crucial traits to predict species resilience to global warming. Here, we study whether captive-bred tadpoles of the gliding treefrog (Agalychnis spurrelli) show different thermal tolerances than wild-caught individuals. Our results show that there are no differences between critical thermal limits (CTmax and CTmin) of captive-bred and wild-caught tadpoles exposed to three-day acclimatization at 20 °C. Therefore, we suggest that the use of captive-bred amphibians is valid and may be appropriate in experimental comparisons to thermal physiological studies of wild populations.
The hypotheses that beta diversity should increase with decreasing latitude and increase with spatial extent of a region have rarely been tested based on a comparative analysis of multiple datasets, and no such study has focused on stream insects. We first assessed how well variability in beta diversity of stream insect metacommunities is predicted by insect group, latitude, spatial extent, altitudinal range, and dataset properties across multiple drainage basins throughout the world. Second, we assessed the relative roles of environmental and spatial factors in driving variation in assemblage composition within each drainage basin. Our analyses were based on a dataset of 95 stream insect metacommunities from 31 drainage basins distributed around the world. We used dissimilaritybased indices to quantify beta diversity for each metacommunity and, subsequently, regressed beta diversity on insect group, latitude, spatial extent, altitudinal range, and dataset properties (e.g., number of sites and percentage of presences). Within each metacommunity, we used a combination of spatial eigenfunction analyses and partial redundancy analysis to partition variation in assemblage structure into environmental, shared, spatial, and unexplained fractions. We found that dataset properties were more important predictors of beta diversity than ecological and geographical factors across multiple drainage basins. In the within-basin analyses, environmental and spatial variables were generally poor predictors of variation in assemblage composition. Our results revealed deviation from general biodiversity patterns because beta diversity did not show the expected decreasing trend with latitude.
Rhodnius ecuadoriensis is the main triatomine vector of Chagas disease, American trypanosomiasis, in Southern Ecuador and Northern Peru. Genomic approaches and next generation sequencing technologies have become powerful tools for investigating population diversity and structure which is a key consideration for vector control. Here we assess the effectiveness of three different 2b restriction site-associated DNA (2b-RAD) genotyping strategies in R. ecuadoriensis to provide sufficient genomic resolution to tease apart microevolutionary processes and undertake some pilot population genomic analyses.
Background: Vaccination is the most effective way to prevent infection and severe outcomes caused by influenza viruses in pregnant women and their children. In Ecuador, the coverage of seasonal influenza vaccination in pregnant women is low. The aim of this study was to assess the knowledge, attitudes, and practices (KAP) of pregnant women toward influenza vaccination in Quito-Ecuador. Methods: A cross-sectional study enrolled 842 women who delivered at three main public gynecological-obstetric units of the Metropolitan District of Quito. A questionnaire regarding demographics, antenatal care, risk conditions and knowledge, attitudes and practices related to influenza vaccination was administered. We examined factors associated with vaccination using log-binomial regression models. Results: A low vaccination rate (36.6%) against influenza was observed among pregnant women. The factorsassociated with vaccination included the recommendations from health providers (adjusted PR: 15.84; CI 95% 9.62–26.10), belief in the safety of the influenza vaccine (adjusted PR: 1.53; CI 95% 1.03–2.37) and antenatal care (adjusted PR: 1.21; CI 95% 1.01–1.47). The most common reasons for not vaccinating included the lack of recommendation from health care providers (73.9%) and lack of access to vaccine (9.0%).Conclusions: Health educational programs aimed at pregnant women and antenatal care providers have the most potential to increase influenza vaccination rates. Further studies are needed to understand the barriers of health care providers regarding influenza vaccination in Ecuador.
Describimos una nueva especie de Pristimantis de la Reserva Buenaventura, al sur del Ecuador, entre elevaciones de 878 y 1082 m. Una filogenia molecular basada en genes nucleares y mitocondriales revela que la nueva especie está cercanamente relacionada a P. phoxocephalus, P. riveti y P. versicolor. La nueva especie difiere de ellas y otros congéneres morfológicamente similares por presentar un pliegue bajo en forma de “W” en la región escapular, un tubérculo cónico sobre el párpado y en el talón, un delgado pliegue mediodorsal y un pliegue lateral longitudinal que se inicia detrás del pliegue timpánico y se extiende a lo largo de dos tercios del flanco. La nueva especie vive en bosques nublados de las estribaciones pacíficas de los Andes.
Sturnira is the most speciose genus of New World leaf-nosed bats (Phyllostomidae). We name Sturnira adrianae, new species. This taxon is born polytypic, divided into a larger subspecies (S. a. adrianae) widespread in the mountains of northern and western Venezuela, and northern Colombia, and a smaller subspecies (S. a. caripana) endemic to the moun-tains of northeastern Venezuela. The new species inhabits evergreen, deciduous, and cloud forests at mainly medium (1000–2000 m) elevations. It has long been confused with S. ludovici, but it is more closely related to S. oporaphilum. It can be distinguished from other species of Sturnira by genetic data, and based on discrete and continuously varying char-acters. Within the genus, the new species belongs to a clade that also includes S. oporaphilum, S. ludovici, S. hondurensis, and S. burtonlimi. The larger new subspecies is the largest member of this clade. The two new subspecies are the most sexually dimorphic members of this clade. The smaller new subspecies is restricted to small mountain systems undergoing severe deforestation processes, therefore can be assigned to the Vulnerable (VU) conservation category of the Internation-al Union for Conservation of Nature (IUCN).
Aim: Pleistocene (2.58 Ma–11.7 ka) climatic fluctuations have shaped intraspecific genetic patterns worldwide; however, their impact on species in many regions re-mains unknown. In order to determine the impact of Pleistocene climatic fluctuations on the tropical rain forests of western Ecuador, we explored the evolutionary history of the endemic palm Phytelephas aequatorialis. Location: Western Ecuador, north-western South America. Taxon: Phytelephas aequatorialis (Arecaceae). Methods: One hundred and seventy-six nuclear genes were sequenced in 91 individuals for phylogenomic and population structure analyses. The time of divergence between identified genetic lineages was estimated using a coalescent phylogenomic analysis. Palaeoecological niche modelling analyses were performed to determine areas of historical climatic suitability since the Last Glacial Maximum (LGM; 22 ka) that potentially acted as forest refugia during the Pleistocene. A Wilcoxon test and Pearson correlations were used to explore how current levels of genetic diversity, in terms of expected heterozygosity (Hs), have been shaped by several palaeoclimatic and geographic factors. Results: Phylogenomic and population structure analyses revealed two main genetic lineages with a north–south distribution, which diverged 1.14 Ma during thePleistocene. Two potential Pleistocene refugia were identified, one along the Pacific coast of Ecuador and one in the Andean foothills of south-western Ecuador. The location of these refugia agrees with the spatial location of the two genetic lineages. Within the Andean foothills, Hs was lower for the southern lineage than for the northern lineage. Hs significantly increased with decreasing latitude across the species as a whole.Main conclusions: Pleistocene climatic fluctuations promoted intraspecific diver-gence in P. aequatorialis within the rain forests of western Ecuador. The Andean foot-hills of south-western Ecuador could be an important area for rain forest evolution
A nationwide survey was conducted to obtain an estimate of Chagas disease prevalence among pregnant women in Ecuador. As part of a national probability sample, 5,420 women seeking care for delivery or miscarriage at 15 healthcare facilities were recruited into the study. A small minority of participants reported knowing about Chagas disease or recognized the vector. A national seroprevalence of 0.1% (95% confidence interval [95% CI] = 0.0–0.2%) was found; cases were concentrated in the coastal region (seroprevalence = 0.2%; 95% CI = 0.0–0.4%). No cases of transmission to neonates were identified in the sample. Seropositive participants were referred to the National Chagas Program for evaluation and treatment. Additional studies are necessary to determine if areas of higher prevalence exist in well-known endemic provinces and guide the development of a national strategy for elimination of mother-to-child transmission of Chagas disease in Ecuador.
The genus Synophis contains a number of enigmatic species, distributed primarily in the Andean highlands of northern South America. Their extreme crypsis and rarity has precluded detailed study of most species. A recent flurry of collection activity resulted in the accession of many new specimens, and the description of 4 new species in 2015, doubling the number of described taxa. However, lingering questions remain regarding the assignment of many new and historical specimens, the morphological limits and geographical ranges of the species, and their phylogenetic relationships. We analyze new and existing morphological and molecular data to produce a new molecular phylogeny and revised morphological descriptions. We validate the previously unavailable tribe name Diaphorolepidini Jenner, Pyron, Arteaga, Echevarría, & Torres-Carvajal tribe nov., describe a 9th species Synophis niceforomariae Pyron, Arteaga, Echevarría, & Torres-Carvajal sp. nov., and offer new Standard Names in English and Spanish for the group: Andean Shadow Snakes and Culebras Andinas de la Sombra, respectively. A variety of features such as vertebrae and hemipenes show an interesting range of variation in the group, which should be evaluated in future studies, to refine species limits and diagnoses further. Cryptic and undiscovered diversity undoubtedly remains, and we hope this summary provides a robust basis for future work.
Anolis lizards (anoles) are textbook study organisms in evolution and ecology. Although several topics in evolutionary biology have been elucidated by the study of anoles, progress in some areas has been hampered by limited phylogenetic information on this group. Here, we present a phylogenetic analysis of all 379 extant species of Anolis, with new phylogenetic data for 139 species including new DNA data for 101 species. We use the resulting estimates as a basis for defining anole clade names under the principles of phylogenetic nomenclature and to examine the biogeographic history of anoles. Our new taxonomic treatment achieves the supposed advantages of recent subdivisions of anoles that employed ranked Linnaean-based nomenclature while avoiding the pitfalls of those approaches regarding artificial constraints imposed by ranks. Our biogeographic analyses demonstrate complexity in the dispersal history of anoles, including multiple crossings of the Isthmus of Panama, two invasions of the Caribbean, single invasions to Jamaica and Cuba, and a single evolutionary dispersal from the Caribbean to the mainland that resulted in substantial anole diversity. Our comprehensive phylogenetic estimate of anoles should prove useful for rigorous testing of many comparative evolutionary hypotheses. [Anoles; biogeography; lizards; Neotropics; phylogeny; taxonomy]
Factores relacionados a la cultura (etnia), género, edad y localidad de residencia de las personas pueden influir sobre el uso que den a las plantas nativas. Mediante el análisis de una encuesta con pruebas de Chi cuadrado, se determinó la influencia de estos factores sobre el aprovechamiento de los frutos de tres especies nativas, en una comunidad mestiza y en otra de mayoría indígena shuar, en la Amazonía central ecuatoriana. El reconocimiento y consumo de los frutos varió entre especies según la manera en que cada uno es consumido (en platos principales, como postre, etc.) y según el grado en que cada uno es cultivado u obtenido del bosque. La recurrencia a los cultivos o al bosque para la cosecha de los frutos varió entre comunidades, tanto por diferencias entre culturas como por diferencias ambientales relacionadas, por ejemplo, a la historia del poblamiento de cada comunidad. Las ocupaciones rutinarias de mujeres y hombres influyeron también sobre la recurrencia a las fuentes de obtención de los frutos. En este caso, el estudio mostró que el gusto por el sabor es una razón muy importante para mantener el consumo de los frutos, mientras que el desconocimiento y la escasez o dificultad para obtenerlos son los principales motivos por los que no se consumen o el consumo es abandonado.
Understanding the blood meal patterns of insects that are vectors of diseases is fundamental in unveiling transmission dynamics and developing strategies to impede or decrease human–vector contact. Chagas disease has a complex transmission cycle that implies interactions between vectors, parasites and vertebrate hosts. In Ecuador, limited data on human infection are available; however, the presence of active transmission in endemic areas has been demonstrated. The aim of this study was to determine the diversity of hosts that serve as sources of blood for triatomines in domestic, peridomestic and sylvatic transmission cycles, in two endemic areas of Ecuador (central coastal and southern highland regions). Using conserved primers and DNA extracted from 507 intestinal content samples from five species of triatomines (60 Panstrongylus chinai, 17 Panstrongylus howardi, 1 Panstrongylus rufotuberculatus, 427 Rhodnius ecuadoriensis and 2 Triatoma carrioni) collected from 2006 to 2013, we amplified fragments of the cytb mitochondrial gene. After sequencing, blood meal sources were identified in 416 individuals (146 from central coastal and 270 from southern highland regions), achieving ≥ 95% identity with GenBank sequences (NCBI-BLAST tool). The results showed that humans are the main source of food for triatomines, indicating that human–vector contact is more frequent than previously thought. Although other groups of mammals, such as rodents, are also an available source of blood, birds (particularly chickens) might have a predominant role in the maintenance of triatomines in these areas. However, the diversity of sources of blood found might indicate a preference driven by triatomine species. Moreover, the presence of more than one source of blood in triatomines collected in the same place indicated that dispersal of vectors occurs regardless the availability of food. Dispersal capacity of triatomines needs to be evaluated to propose an effective strategy that limits human–vector contact and, in consequence, to decrease the risk of T. cruzi transmission.
Many Amazonian frog species that are considered widely distributed may actually represent polyspecific complexes. A minute tree frog from the Guiana Shield originally assigned to the allegedly widely distributed Dendropsophus brevifrons proved to be a yet undescribed species within the D. parviceps group. We herein describe this new species and present a phylogeny for the D. parviceps group. The new species is diagnosed from other Dendropsophus of the parviceps group by its small body size (19.6–21.7 mm in males, 22.1–24.5 mm in females), thighs dorsally dark grey with cream blotches without bright yellow patch, absence of dorsolateral and canthal stripe, and an advertisement call comprising trills (length 0.30–0.35 s) composed of notes emitted at a rate of 131–144 notes/s, generally followed by click series of 2–3 notes. Its tadpole is also singular by having fused lateral marginal papillae and absence of both labial teeth and submarginal papillae. Genetic distances (p-distance) are >5.3% on the 12S and >9.3% on the 16S from D. brevifrons, its closest relative. This species occurs from the Brazilian state of Amapá, across French Guiana and Suriname to central Guyana and is likely to also occur in adjacent Brazilian states and Eastern Venezuela. This species is not rare but is difficult to collect because of its arboreal habits and seasonal activity peaks.
El Murciélago de orejas redondas de Yasuní, Lophostoma yasuni, fue descrito en 2004 a partir del análisis morfológico del holotipo, el único espécimen colectado de ese taxón hasta la fecha. Se realizó un análisis molecular basado en citocromo-b y una nueva revisión morfológica que incluyó el holotipo de L. yasuni y dos especímenes de L. carrikeri recientemente colectados en las cercanías a la localidad tipo de L. yasuni. La nueva evidencia sitúa a L. yasuni dentro del clado de L. carrikeri. Proponemos que L. yasuni sea considerado un sinónimo de L. carrikeri. Se presenta una diagnosis corregida para L. carrikeri que amplía los rangos de las medidas cráneo-dentales reportadas para esta especie.
Abstract Background: In this study, the genetic substructure and morphology of the species Neusticomys monticolus was evaluated. A nuclear marker and mitochondrial maker were used to examine phylogeographic structure and to estimate genetic distances. Two statistical measurement analyses were applied to morphological data. Results: These data recovered two morphologically distinct phylogeographic groups corresponding to populations on the eastern and western slopes of the Andes. Further, these eastern and western Andean slope populations of N. monticolus are 8.5 % divergent using sequence data from cytochrome-b (0.8 % divergent in the interphotoreceptor retinoid-binding protein gene). Conclusions: Populations currently assigned to N. monticolus constitute a species complex. The name N. monticolus is here restricted to western Andean slope populations. Populations on the eastern slope of the Andes are assigned to a new species, to which the authors assign the name Neusticomys vossi sp. nov.
We describe a new species of Anolis from the Andes of northern Peru. This form is similar to species formerly assigned to the genus Phenacosaurus and to Ernest Williams’ tigrinus series. That is, the new species possesses large smooth headscales, cryptic coloration, and short limbs and tail. We present new DNA and morphological data and perform a comprehensive phylogenetic analysis of the Dactyloa clade of Anolis. The new species is estimated to be close to phenotypically similar species from Peru and Venezuela. We revise the taxonomy of Dactyloa based on our estimate. Most previously recognized phylogenetically defined groups are retained with restricted species contents. Several species currently scorable only for morphological data could not be placed in any group with confidence. The species status of the enigmatic mainland form Anolis deltae should be re-examined with reference to the roquet group of southern Lesser Antillean Anolis.
Quimsacocha National Recreation Area is located on the western slope of the Andes in Azuay Province, southern Ecuador. All sampling locations were in the high paramo and high Andean forests (3,572 to 3,865 m). The habitats in clude paramo, bogs, riparian, patches of elfin forests, and secondary cloud forest. We set Sherman, pitfall, and camera traps (3,600 trap nights), and mist nets to collect 117 specimens. Eight species were collected, including Caenolestes caniventer Anthony 1921; Didelphis pernigra J.A. Allen, 1900; Cryptotis montivagus (Anthony, 1921); Akodon mollis Thomas, 1894; Microryzomys altissimus (Osgood, 1933), Phyllotis haggardi Thomas, 1908; Sigmodon inopinatus Anthony, 1924; and Sylvilagus andinus (Thomas, 1897). Two additional species Coendou rufescens (Gray, 1865) and Odocoileus virginianus (Zimmermann, 1780) were documented photographically. This is the first survey that saved voucher specimens for mammals of Quimsacocha.
The cataloging of the vascular plants of the Americas has a centuries-long history, but it is only in recent decades that an overview of the entire flora has become possible.We present an integrated assessment of all known native species of vascular plants in the Americas. Twelve regional and national checklists, prepared over the past 25 years and including two large ongoing flora projects, were merged into a single list. Our publicly searchable checklist includes 124,993 species, 6227 genera, and 355 families, which correspond to 33% of the 383,671 vascular plant species known worldwide. In the past 25 years, the rate at which new species descriptions are added has averaged 744 annually for the Americas, and we can expect the total to reach about 150,000
Urban river pollution by multidrug-resistant (MDR) bacteria constitutes an important public health concern. Epidemiologically important strains of MDR Escherichia coli transmissible at the human–animal–environment interfaces are especially worrying. Quantifying and characterizing MDR E. coli at a molecular level is thus imperative for understanding its epidemiology in natural environments and its role in the spread of resistance in precise geographical areas. Cefotaxime-resistant E. coli was characterized along the watercourse of the major urban river in Quito. Our results showed high quantities of cefotaxime-resistant E. coli (2.7 × 103–5.4 × 105 CFU/100 mL). The antimicrobial resistance index (ARI) revealed the exposure of the river to antibiotic contamination, and the multiple antibiotic resistance index indicated a high risk of contamination. The blaCTX-M-15 gene was the most prevalent in our samples. Isolates also had class 1 integrons carrying aminoglycoside-modifying enzymes and folate pathway inhibitors. The isolates belonged to phylogroups A, B1 and D. Clonal complex 10 was found to be the most prevalent (ST10, ST44 and ST 167), followed by ST162, ST394 and ST46. Our study provides a warning about the high potential of the major urban river in Quito for spreading the epidemiologically important MDR E. coli.
1. A major barrier for the scientific community of climate change biologists is the spatial mismatch between the size of organisms and the resolution at which global climate data are collected and modelled. Thus, the development of integrative and quantitative tools for the monitoring and spatial characterization of microclimates across spatial scales is a key issue for climate change ecologists. 2. We proposed an integrative toolbox for quantifying the spatial heterogeneity in surface temperatures by bringing together procedures of unmanned aerial vehicles, thermal imagery, orthomosaic, GIS classification and spatial metrics. This toolbox permits to yield high‐resolution visual and infrared orthoimages that are processed into a GIS for selecting surfaces of interest in the landscape (e.g. soil, vegetation). Then, the thermal matrices of selected surfaces (i.e. temperature values of the pixels belonging to the selected surfaces only) are processed within R to generate a variety of thermal landscape metrics (e.g. thermal patch richness and density, thermal aggregation and cohesion index). 3. We applied this toolbox to the thermal characterization of mountainous agricultural landscapes in Ecuador with implications for ectothermic pest dynamics. UAV flights at a height of 60 m above‐ground level allowed us to acquired high‐resolution visual and thermal images (1 and 5 cm/pixel, respectively) for 12 potato fields with a mean surface of 1017 ± 117 m2.
We investigated the relationship between egg and cell sizes in the early gastrula of ten species of frogs with eggs of 1,100–3,500 μm diameters. We asked whether differences in cell size of the vegetal region, blastocoel roof, and marginal zone of the early gastrula were associated with egg size. Alternatively, we proposed that cell size differences may associate with gastrulation characteristics. The analyzed species were as follows: Xenopus laevis, Engystomops randi, Engystomops coloradorum, Espadarana callistomma, Epipedobates machalilla, Epipedobates anthonyi, Epipedobates tricolor, Dendrobates auratus, Gastrotheca riobambae, and Eleutherodactylus coqui. A positive correlation between egg and cell size was detected in the three regions of the gastrula. The correlation was strong in the vegetal region and blastocoel roof, and weak in the marginal zone. Large eggs allowed the evolution of frog terrestrial reproductive modes by storing nourishment for the developing embryos. Large cells, laden with yolk, occur in the vegetal region. However, small cell size characterized the marginal zone and blastocoel roof. We proposed that small cells of the marginal zone are required for involution and blastopore formation. The evolution pressure toward small cells in the marginal zone contributed to maintain the blastopore as a universal feature of frog gastrulation in eggs of different sizes and gastrulation modes. Our comparative analysis revealed two fundamental and conserved properties of the frog early gastrula, the correlation of egg with cell sizes, and the general small size of cells in the marginal zone
The elimination of domestic triatomines is the foundation of Chagas disease control. Regional initiatives are eliminating introduced triatomine species. In this scenario, endemic triatomines can occupy the ecological niches left open and become a threat to long-term Chagas disease control efforts. This study determined the abundance, colonization, and Trypanosoma cruzi infection rate of the endemic Panstrongylus howardi in 10 rural communities located in Ecuador’s Manabı´ Province. In total, 518 individuals of P. howardi were collected. Infestation indices of 1.4% and 6.6% were found in the domestic and peridomestic environments, respectively. We determined a T. cruzi infection rate of 53.2% (N = 47) in this species. P. howardi has a high capacity to adapt to different habitats, especially in the peridomicile. This implies a considerable risk of transmission because of the frequency of intradomicile invasion. Therefore, this species needs to be taken into account in Chagas control and surveillance efforts in the region.
El mercurio es considerado un contaminante altamente peligroso debido a su elevada toxicidad y a su carácter acumulativo. Presenta varios efectos en la salud humana, tales como: trastornos del sistema nervioso, deterioro intelectual, problemas gastrointestinales y cáncer. El uso de técnicas electroquímicas es una alternativa para la cuantificación de mercurio a niveles traza, debido a su bajo costo y buena sensibilidad. En este trabajo de investigación se evaluó un microelectrodo de fibra de carbono modificado con nanopartículas de oro para la determinación de mercurio (II) en medio acuoso. Se realizó la modificación superficial de la fibra de carbono electrodepositando nanopartículas de oro, a un potencial de -0,1 V durante 100 s, y se utilizó microscopía electrónica de barrido y voltamperometría cíclica para confirmar la presencia de nanopartículas de oro. Se cuantificó el mercurio (II) mediante voltamperometría de redisolución anódica de pulso diferencial. Se obtuvo un rango lineal, en la curva de calibración, entre 50 - 100 μg L-1 de mercurio (II). Los límites de detección y de cuantificación obtenidos fueron de 38 y 46 μg L-1, respectivamente. La validación de la metodología se realizó mediante porcentaje de recuperación, obteniendo valores entre 94 y 104 % y desviación estándar relativa (RSD, por sus siglas en inglés) entre 3,6 y 4,7 %. El método propuesto muestra características útiles para su implementación en el monitoreo de contaminación por mercurio.
Climate changes are occurring rapidly at both regional and global scales. Farmers are faced with the challenge of developing new agricultural practices to help them to cope with unpredictable changes in environmental, social, and economic conditions. Under these conditions, adaptive management requires a farmer to learn by monitoring provisional strategies and changing conditions, and then incrementally adjust management practices in light of new information. Exploring adaptive management will increase our understanding of the underlying processes that link farmer societies with their environment across space and time, while accounting for the impacts of an unpredictable climate. Here, we assessed the impacts of temperature and crop price, as surrogates for climate and economic changes, on farmers’ adaptive management in crop pest control using an agent-based modeling approach. Our model simulated an artificial society of farmers that relied on field data obtained in the Ecuadorian Andes. Farmers were represented as heterogeneous autonomous agents who interact with and influence each other, and who are capable of adapting to changing environmental conditions. The results of our simulation suggest that variable temperatures led to less effective pest control strategies than those used under stable temperatures. Moreover, farmers used information gained through their own past experience or through interactions with other farmers to initiate an adaptive management approach. At a broader scale, this study generates more than an increased understanding of adaptive management; it highlights how people depend on one another to manage common problems.
La sociedad en la que vivimos puede ser descrita como un sistema de comunicaciones alta mente complejo, diferenciado en múltiples subsistemas, cuyas operaciones tienen un alcance mundial (Luhmann, 2007). A estas alturas de su evolución histórica, es evidente que la sociedad moderna no tiende a la armonía ni al “progreso”, al contrario, se trata de un sistema alejado del equilibrio, cuya creciente complejidad lo expone a diversas perturbaciones, sin que existan ajustes automáticos ni mecanismos claros que garanticen la solución de los problemas. La sociedad moderna se “irrita” constantemente a sí misma, tanto en su ambiente interno (las relaciones entre los subsistemas), como en lo que respecta a su entorno (el medio ambiente ecológico y los individuos humanos).
Urbanization rates are increasing worldwide; therefore, urban and semi-urban ecosystems are the focus of various studies that explore their importance for biodiversity conservation. In the order Lepidoptera high species diversity has been observed in areas with distinct levels of disturbance. In Ecuador, most efforts to study the diversity of butterflies have been concentrated in protected natural areas, whereas studies in semi-urban or urban areas are limited. In this study, we measured the diversity of diurnal Lepidoptera in two semi-urban areas, in southern Ecuador. We visited these areas during the dry season, in the hours of peak butterfly activity, and recorded the species and abundances of each. We estimated relative abundances, evenness, and beta diversity to characterize butterfly assemblages. We found high abundance and richness of Lepidoptera species and low similarities between the two semi-urban areas (Jaccard index = 0.21). Highest species richness was observed in the most heterogeneous area in terms of vegetation composition, owing to the type of management that it receives. Four species represented 50% of the total abundance observed in both sites, and various singletons were registered. This pattern of dominance is characteristic of disturbed areas, where generalist species adapt easily to anthropic environments. However, we also found relatively high richness and abundance of the members of the tribe Ithomiini, which are mostly present in primary forests. Our findings highlight the importance of semi-urban areas for conservation of butterfly diversity and the crucial role of proper management of anthropic areas to preserve biodiversity in this changing world.
The shapes of cosmic voids are prone to distortions caused by external tidal forces since their low densities imply a lower internal resistance. This susceptibility of the void shapes to tidal distortions makes them useful as indicators of large-scale tidal and density fields, despite the practical difficulty in defining them. Using the void catalog constructed by Pan et al. from the Seventh Data Release of the Sloan Digital Sky Survey (SDSS DR7), we detect a clear 4σ signal of spatial correlations of the void shapes on a scale of 20 h-1Mpc and show that the signal is robust against the projection of the void shapes onto the plane of sky. By constructing a simple analytic model for the void shape correlation, within the framework of tidal torque theory, we demonstrate that the void shape correlation function scales linearly with the two-point correlation function of the linear density field. We also find direct observational evidence for the cross-correlation of the void shapes with the large-scale velocity shear field that was linearly reconstructed by Lee et al. from SDSS DR7. We discuss the possibility of using the void shape correlation function to break the degeneracy between the density
Several microwave-assisted digestion methods were tested at the Centro de Estudios Aplicados en Química laboratory in Quito, Ecuador, to determine the accuracy and performance efficiency of the mineralization process for the determination of total mercury in fish tissue by cold vapor atomic fluorescence spectrophotometry. The use of MARSEasyPrep high-pressure vessels, low amounts of reagents (1 cm3 HNO3, 1 cm3 H2O2, and 1 cm3 HClO4), an irradiation temperature of 210 °C, and 35 min of mineralization time resulted in accurate performance, with recoveries of certified reference material DORM-4 between 90.1% and 105.8%. This is better than the Association of Official Analytical Chemists 2015.01 method, which has a reported accuracy of 81%. The repeatability precision and intermediate precision were established at three concentration levels (0.167, 0.500, and 0.833 mg·kg−1) and expressed as the percentage of the relative standard deviation ranging from 1.5% to 3.0% and 1.7% to 4.2%, respectively. Further, the method was satisfactorily applied to analyze fortified samples of tilapia (Oreochromis niloticus), with recoveries ranging from 98.3% to 104.3%. The instrumental limits of detection and quantification were 0.118 µg·dm−3 and 0.394 µg·dm−3, respectively.
Globally, a majority of people use plants as a primary source of healthcare and introduced plants are increasingly discussed as medicine. Protecting this resource for human health depends upon understanding which plants are used and how use patterns will change over time. The increasing use of introduced plants in local pharmacopoeia has been explained by their greater abundance or accessibility (availability hypothesis), their ability to cure medical conditions that are not treated by native plants (diversification hypothesis), or as a result of the introduced plants' having many different simultaneous roles (versatility ypothesis). In order to describe the role of introduced plants in Ecuador, and to test these three hypotheses, we asked if introduced plants are over-represented in the Ecuadorian pharmacopoeia, and if their use as medicine is best explained by the introduced plants' greater availability, different therapeutic applications, or greater number of use categories. Drawing on 44,585 plant-use entries, and the checklist of >17,000 species found in Ecuador, we used multi-model inference to test if more introduced plants are used as medicines in Ecuador than expected by chance, and examine the support for each of the three hypotheses above. We find nuanced support for all hypotheses. More introduced plants are utilized than would be expected by chance, which can be explained by geographic distribution, their strong association with cultivation, diversification (except with regard to introduced diseases), and therapeutic versatility, but not versatility of use categories. Introduced plants make a disproportionately high contribution to plant medicine in Ecuador.
An international study was performed by 26 experienced PCR laboratories from 14 countries to assess the performance of duplex quantitative real-time PCR (qPCR) strategies on the basis of TaqMan probes for detection and quantification of parasitic loads in peripheral blood samples from Chagas disease patients. Two methods were studied: Satellite DNA (SatDNA) qPCR and kinetoplastid DNA (kDNA) qPCR. Both methods included an internal amplification control. Reportable range, analytical sensitivity, limits of detection and quantification, and precision were estimated according to international guidelines. In addition, inclusivity and exclusivity were estimated with DNA from stocks representing the different Trypanosoma cruzi discrete typing units and Trypanosoma rangeli and Leishmania spp. Both methods were challenged against 156 blood samples provided by the participant laboratories, including simples from acute and chronic patients with varied clinical findings, infected by oral route or vectorial transmission. kDNA qPCR showed better analytical sensitivity than SatDNA qPCR with limits of detection of 0.23 and 0.70 parasite equivalents/mL, respectively. Analyses of clinical samples revealed a high concordance in terms of sensitivity and parasitic loads determined by both SatDNA and kDNA qPCRs. This effort is a major step toward international validation of qPCR methods for the quantification of T. cruzi DNA in human blood samples, aiming to provide an accurate surrogate biomarker for diagnosis and treatment monitoring for patients with Chagas disease.
Biatriospora (Ascomycota: Pleosporales, Biatriosporaceae) is a genus with unexplored diversity and poorly known ecology. This work expands the Biatriospora taxonomic and ecological concept by describing four new species found as endophytes of woody plants in temperate forests of the Czech Republic and in tropical regions, including Amazonia. Ribosomal DNA sequences, together with protein-coding genes (RPB2, EF1a), growth rates and morphology, were used for species delimitation and description. Ecological data gathered by this and previous studies and the inclusion of sequences deposited in public databases show that Biatriospora contains species that are endophytes of angiosperms in temperate and tropical regions as well as species that live in marine or estuarine environments. These findings show that this genus is more diverse and has more host associations than has been described previously. The possible adaptations enabling the broad ecological range of these fungi are discussed. Due to the importance that Biatriospora species have in bioprospecting natural products, we suggest that the species introduced here warrant further investigation
Background Aedes aegypti is the primary vector of dengue fever, a viral disease which has an estimated incidence of 390 million infections annually. Conventional vector control methods have been unable to curb the transmission of the disease. We have previously reported a novel method of vector control using a tetracycline repressible self-limiting strain of Ae. Aegypti OX513A which has achieved >90% suppression of wild populations. Methodology/Principal Findings We investigated the impact of tetracycline and its analogues on the phenotype of OX513A from the perspective of possible routes and levels of environmental exposure.We determined the minimum concentration of tetracycline and its analogues that will allow an increased survivorship and found these to be greater than the maximum concentration of tetracyclines found in known Ae. aegypti breeding sites and their surrounding areas. Furthermore, we determined that OX513A parents fed tetracycline are unable to pre-load their progeny with sufficient antidote to increase their survivorship. Finally, we studied the changes in concentration of tetracycline in the mass production rearing water of OX513A and the developing insect. Conclusion/Significance Together, these studies demonstrate that potential routes of exposure of OX513A individuals to tetracycline and its analogues in the environment are not expected to increase the survivorship of OX513A.
The generalist parasite Trypanosoma cruzi has two phylogenetic lineages associated almost exclusively with bats—Trypanosoma cruzi Tcbat and the subspecies T. c. marinkellei. We present new information on the genetic variation, geographic distribution, host associations, and potential vectors of these lineages. We conducted field surveys of bats and triatomines in southern Ecuador, a country endemic for Chagas disease, and screened for trypanosomes by microscopy and PCR. We identified parasites at species and genotype levels through phylogenetic approaches based on 18S ribosomal RNA (18S rRNA) and cytochrome b (cytb) genes and conducted a comparison of nucleotide diversity of the cytb gene. We document for the first time T. cruzi Tcbat and T. c. marinkellei in Ecuador, expanding their distribution in South America to the western side of the Andes. In addition, we found the triatomines Cavernicola pilosa and Triatoma dispar sharing shelters with bats. The comparisons of nucleotide diversity revealed a higher diversity for T. c. marinkellei tan any of the T. c. cruzi genotypes associated with Chagas disease. Findings from this study increased both the number of host species and known geographical ranges of both parasites and suggest potential vectors for these two trypanosomes associated with bats in rural areas of southern Ecuador. The higher nucleotide diversity of T. c. marinkellei supports a long evolutionary relationship between T. cruzi and bats, implying that bats are the original hosts of this important parasite.
Los integrones son estructuras observadas con frecuencia en bacilos Gram negativos, especialmente entre los miembros de la familia Enterobacteriaceae. Se estudió la presencia de integrones clase 1 y su relación con la resistencia bacteriana. La presencia de integrones fue estudiada por medio de la reacción en cadena de la polimerasa (PCR) y secuenciación. Se analizaron treinta aislados resistentes a carbapenemes de Klebsiella pneumoniae que fueron positivos para el gen de la integrasa 1 (intI1). En veintiseis de estos aislados se amplificaron regiones variables de alrededor de 2 000 pares de bases. El patrón común de genes obtenidos mediante el análisis de estas regiones fue (dfrA12 - orfF - aadA2). La presencia de estas plataformas que promueven la diversidad genética provee a las bacterias de resistencia a una amplia gama de antibióticos. La alta prevalencia de integrones observadas entre estos aislados funciona como fuente de difusión de determinantes de resistencia.
A new categorical setting is defined in order to characterize the subrecursive classes belonging to complexity hierarchies. This is achieved by means of coercion functors over a symmetric monoidal category endowed with certain recursion schemes that imitate the bounded recursion scheme. This gives a categorical counterpart of generalized safe composition and safe recursion .
An endophytic fungus was isolated that produces a series of volatile natural products, including terpenes and odd chain polyenes. Phylogenetic analysis of the isolate using five loci suggests that it is closely related to Nigrograna mackinnonii CBS 674.75. The main component of the polyene series was purified and identified as (3E,5E,7E)-nona- 1,3,5,7-tetraene (NTE), a novel natural product. Nonoxygenated hydrocarbons of this chain length are uncommon and desirable as gasoline-surrogate biofuels. The biosynthetic pathway for NTE production was explored using metabolic labeling and gas chromatography time of flight mass spectometer (GCMS). Two-carbon incorporation 13C acetate suggests that it is derived from a polyketide synthase (PKS) followed by decarboxylation. There are several known mechanisms for such decarboxylation, though none have been discovered in fungi. Towards identifying the PKS responsable for the production of NTE, the genome of N. mackinnonii E5202H (ATCC SD-6839) was sequenced and assembled. Of the 32 PKSs present in the genome, 17 are predicted to contain sufficient domains for the production of NTE. These results exemplify the capacity of endophytic fungi to produce novel natural products that may have many uses, such as biologically derived fuels and commodity chemicals.
A recent study by Cartelle Gestal et al. reported an analysis of data from the Ministry of Public Health on the epidemiological situation of neglected tropical diseases in Ecuador . Based on a misleading definition of Chagas disease cases not corresponding to that of the Ministry of Public Health , the authors concluded that the government had mounted successful control campaigns, and as a result Chagas disease (among others) had been effectively controlled as no cases in children under age five had been reported since 2009. Ecuador is thus identified as one of the first countries to control Chagas disease. While we certainly agree that efforts have been made in terms of Chagas disease surveillance and control campaigns in Ecuador, a more comprehensive analysis of available data, from both the Ministry of Public Health and the literature, provides a very different picture, and the claim that Chagas disease is controlled made by Cartelle Gestal et al. seems largely inadequate and sends an equivocal message which can undermine current control efforts. As mentioned in this study, the Chagas disease control program in the country was formally established in 2003–2004, in response to recommendations from a technical consultation through PAHO/WHO  and field studies [4,5]. This consultation and data provided a baseline to prioritize activities. It reported a national seroprevalence of Trypanosoma cruzi infection of 1.38%, corresponding to 165–170,000 seropositive patients in the country.
La entomología forense permite esclarecer los hechos y determinar responsabilidades en casos de homicidios, suicidios, abandono y negligencia. Además, la entomología forense nos ayuda a valorar (de manera cuantitativa y cualitativa) la presencia de sustancias tóxicas en el cuerpo del fallecido, así como evidenciar el posible traslado de cadáveres. El desarrollo de esta ciencia se basa en la generación de información científica, la cual es interpretada por expertos en el tema para ser utilizada como evidencia ante las cortes. La puesta en práctica de procedimientos simples y eficaces va a determinar la correcta utilización de muestras entomológicas, integrando a esta disciplina en la cadena criminalística. En la presente nota se exponen los distintos avances y metas obtenidas tanto en la generación de información científica, como en las capacitaciones e intercambio de conocimientos entre el grupo de investigadores, el Área de entomología forense de la PUCE y los funcionarios de la FGE.
Background: Excess weight (overweight and obesity) is the major modifiable risk factor for type 2 diabetes mellitus (T2DM) and other non-communicable diseases. However, excess weight may not be as predictive of diabetes risk as once thought. While excess weight and other obesity-related non-communicable diseases are of growing concern in low-middle income countries in Latin America, there is limited research on risk factors associated with T2DM in adolescents. This study investigated prevalence of overweight, obesity, prediabetes, diabetes and metabolic syndrome in adolescents in Ecuador. Methods: A cross-sectional study was conducted with 433 adolescents from two schools in a small urban center in southern Ecuador and two schools in a large urban center in Quito. Risk factors were measured, including: height, weight, BMI, waist-to-hip ratio, fasting glucose, lipid panel, and HbA1c. Multivariate analysis of variance (MANOVA) was separately applied to risk factors and demographic factors as a set of dependent variables with sex, location and their interaction included as predictors. An independent t test was run on the data at 95% confidence intervals for the mean difference. The values for the triglycerides, LDL and VLDL were positively skewed. A Mann–Whitney U test was run on these data.
In the past 5–10 years, Venezuela has faced a severe economic crisis, precipitated by political instability and declining oil revenue. Public health provision has been affected particularly. In this Review, we assess the impact of Venezuela’s health-care crisis on vector-borne diseases, and the spill over into neighbouring countries. Between 2000 and 2015, Venezuela witnessed a 359% increase in malaria cases, followed by a 71% increase in 2017 (411 586 cases) compared with 2016 (240 613). Neighbouring countries, such as Brazil, have reported an escalating trend of imported malaria cases from Venezuela, from 1538 in 2014 to 3129 in 2017. In Venezuela, active Chagas disease transmission has been reported, with seroprevalence in children (<10 years), estimated to be as high as 12·5% in one community tested (n=64). Dengue incidence increased by more than four times between 1990 and 2016. The estimated incidence of chikungunya during its epidemic peak is 6975 cases per 100 000 people and that of Zika virus is 2057 cases per 100 000 people. The re-emergence of many vector-borne diseases represents a public health crisis in Venezuela and has the possibility of severely undermining regional disease elimination efforts. National, regional, and global authorities must take action to address these worsening epidemics and prevent their expansion beyond Venezuelan borders.
Burmeistera zamorensis Muchhala & A. J. Pérez (Campanulaceae, Lobelioideae)from cloud forests in Zamora Chinchipe, Ecuador. It is distinctive in possessing inflated fruit with thick, fleshy walls, and in the maroon coloration of the ventral surface of its leaves, which the dark green of the dorsal leaf surfaces. Although similar to B. ceratocarpa Zahlbr. and B. glabrata (Kunth) Benth. & Hook. f. ex B. D. Jacks., the new species can be distinguished from these and all other species of Burmeistera Triana by a combination of characters that includes leaf arrangement, fruit morphology, and calyx lobe morphology.
Travellers’ diarrhoea (TD) is the foremost health problem contracted abroad by United States citizens, affecting between 20% and 60% of those travelling to developing countries (www.cdc.gov). The aim of this study was to report the ﬁrst Salmonella spp. resistant to broad spectrum antibiotics reported in Ecuador. Identiﬁcation and sensitivity proﬁle were performed using VITEK2® compact (bioMérieux, USA). Serotype was conﬁrmed by agglutination in the National Reference Laboratory, INSPI, Quito, Ecuador. Plasmid extraction was performed following the manufacturer’s instructions (Pure Yield Plasmid Miniprep System, Promega, United Kingdom). ERIC-PCR was performed following the conditions previously described.1 The PCR for ampliﬁcation of the CTX-M gene was performed as previously described.2 Puriﬁcation of the PCR ampliﬁcation from the agarose gel was performed following the manufacturer’s instructions (Wizard® SV Gel and PCR Clean-Up System, Promega) and sequenced in Macrogen, South Korea. From a total of 28 strains of Salmonella spp. isolated in the laboratory (January 2014–July 2015), ﬁve isolates were of the same clone which presented high resistance to antibiotics. The identiﬁcation and serotyping showed that the strain cor- responded to Salmonella enterica serovar Infantis harbouring CTX-M-65. ERIC-PCR conﬁrmed the isolates were of the same clone (Fig. 1). This is the ﬁrst time a CTX-M 65 has been found outside of Asia, highlighting the importance of a good antibiotic policy in all countries as resistance can be easily disseminated around the world due to travel and trade.
In the present study, we performed a computational study to gain insights on the binding mode and high affinity of pregabalin, its inactive isomer (R-pregabalin) and gabapentin when modulating voltage-gated calcium channels. Quantum chemical descriptors were evaluated at two different levels of theory (ωB97XD and B3LYP-D3) for the three molecules. The results show that the three ligands have similar quantum chemical descriptors, suggesting that the affinity is governed by the binding pose and the ability to access the pocket. The binding mode analysis of pregabalin indicates that it is interacting with 12 residues (6 hydrogen bonds) including Arg217, which is key to pregabalin action mechanism. Our results suggest that the electrostatic interactions and the hydrogen bonds between pregabalin and Arg217 could explain its high affinity, highlighting the importance of Arg217 in the pharmacological action
1. In order to assess the impact of global warming on the biodiversity of the tropical high Andean paramo ecosystem, we compared historical and recent surveys of ground beetle communities along elevational gradients of the Pichincha volcano (Northern Ecuador). The studied datasets date to 1880, 1985/86 and 2013/15. 2. From 1880 to 1985, the bottom range of at least one stenotopic and wingless high-altitude species, Dyscolus diopsis, has shifted approximately 300 m upward, with the resulting area reduction of more than 90% from >12 km2 to <1 km2, which highlights the probability of future local extinctions on the Pichincha as well as on other mountains of Ecuador. 3. Over a shorter period of time, the comparison of the 1985/86 and 2013/14 datasets indicates that the lower limit of the superparamo ground beetle community has shifted upwards from circa 4300 m to circa 4400 m. Different individual responses are recorded among the species. Some of them did not experience any signiﬁcant change, whereas the upper limit of one of the grassland generalists has shifted upwards at least 400 m in 28 years. 4. These results suggest that the response to global warming varies from one species to the other, depending on their degree of specialisation and tolerance. They call for the implementation of a monitoring programme that would use carabid assemblages as an indicator of the impact of climate change on the paramo ecosystem, in combination with other proxies.
Abstract Vicarious nucleophilic substitution reactions are a versatile way of introducing substituents into aromatic and heteroaromatic electron-deficient compounds. In this project, a kinetic study of these reactions by applying quantum mechanics concepts, such as reaction force, force constant, and electronic reaction flow was proposed. Furthermore, absolute theoretical scales of electrophilicity by applying density functional theory electronic indices were established to classify a series of five and six-membered nitroheteroarenes, and nitrobenzenes with substituents in ortho, meta and para positions. The theoretical model was validated by comparison with experimental kinetic results. Calculations using B3LYP/6- 311G(d,p) level of theory allowed analysis of the reactivity patterns and the mechanisms of these chemical reactions. The theoretical scale properly accounts for the activating/ deactivating effects promoted by the substituents and agrees with the ability of these substituents to accept or donate electrons, electron acceptor substituents are those that increase electrophilicity, and electron donors those that reduce it.
PREMISE: Third-generation sequencing methods generate significantly longer reads than those produced using alternative sequencing methods. This provides increased possibilities for the study of biodiversity, phylogeography, and population genetics. We developed a protocol for in-solution enrichment hybridization capture of long DNA fragments applicable to complete plastid genomes. METHODS AND RESULTS: The protocol uses cost-effective in-house probes developed via long-range PCR and was used in six non-model monocot species (Poaceae: African rice, pearl millet, fonio; and three palm species). DNA was extracted from fresh and silica gel–dried leaves. Our protocol successfully captured long-read plastome fragments (3151 bp median on average), with an enrichment rate ranging from 15% to 98%. DNA extracted from silica gel–dried leaves led to low-quality plastome assemblies when compared to DNA extracted from fresh tissue. CONCLUSIONS: Our protocol could also be generalized to capture long sequences from specific nuclear fragments.
Las secreciones de la piel de Agalychnis spurrelli han probado tener una marcada actividad antimicrobiana sobre diferentes microrganismos patógenos por la presencia de biomoléculas en ellas. Se realizaron análisis moleculares del ARN mensajero de la piel de A. spurrelli para determinar el tipo de péptido antimicrobiano presente en las secreciones cutáneas de esta especie. Para amplificar las secuencias precursoras de los péptidos maduros, se utilizaron iniciadores específicos que contienen secuencias altamente conservadas. Como resultado se obtuvo una secuencia de ADN complementario de 357 pb, la cual fue comparada con sus ortólogos de otras especies de la misma subfamilia Phyllomedusinae, se lograron índices de identidad muy altos para precursores de dermaseptinas. Finalmente, para el análisis de la secuencia de ADN complementario, se tradujo la secuencia nucleotídica por codones, con lo que se obtuvo una secuencia aminoacídica. Dicha secuencia posee las características particulares de péptidos de la familia de las dermaseptinas: una secuencia altamente conservada, una propieza acídica con los aminoácidos Lisina y Arginina y el extremo C-terminal variable. En conclusión, la secreción total de Agalychnis spurrelli contiene un péptido de la familia de las dermaseptinas o un péptido relacionado con ellas.
Several human coronaviruses (HCoVs) are distinguished by the ability to generate epidemics or pandemics, with their corresponding diseases characterized by severe respiratory illness, such as that which occurs in severe acute respiratory síndrome (SARS-CoV), Middle East respiratory syndrome (MERS-CoV), and, today, in SARS-CoV-2, an outbreak that has struck explosively and uncontrollably beginning in December 2019 and has claimed the lives of more than 1.9 M people worldwide as of January 2021. The development of vaccines has taken one year, which is why it is necessary to investigate whether some already-existing alternatives that have been successfully developed in recent years can mitigate the pandemic's advance. Silver nanoparticles (AgNPs) have proved effective in antiviral action. Thus, in this review, several in vitro and in vivo studies of the effect of AgNPs on viruses that cause respiratory diseases are analyzed and discussed to promote an understanding of the possible interaction of AgNPs with SARS-CoV-2. The study focuses on several in vivo toxicological studies of AgNPs and a dose extrapolation to humans to determine the chief avenue of exposure. It can be concluded that the use of AgNPs as a possible treatment for SARS-CoV-2 could be viable, based on comparing the virus' behaviorto that of similar viruses in in vivo studies, and that the suggested route of adminis-tration in terms of least degree of adverse effects is inhalation.
A first count of the species richness of insects with forensic value for Ecuador is presented in this article. The list is based on published literature and specimen records deposited at the Museo QCAZ – Invertebrados. A list of species and their distribution by province is presented. We further provide a map of localities. In total, our search resulted in 356 species of forensic value for South America. From this, 99 species were recorded in Ecuador. The most common insect orders are Diptera and Coleoptera. The provinces with the highest number of records were Galápagos and Pichincha. Our catalogue provides a baseline that we hope can promote and motivate future work on these fascinant insects with legal value.
Biosphere reserves are protected areas with extraordinary natural and cultural values, conceived as places for reconciliation between conservation and development. The Sumaco Biosphere Reserve (SBR), located in the Northern Ecuadorian Amazon basin is the home of local indigenous communities which have lived in this area for centuries carrying out different subsistence activities (e.g. shifting cultivation, hunting, fishing, and home gardening). During the past decades, tourism initiatives have been implemented as strategies to promote environmental conservation and socio-economic development. In this research, the principal aspects of the management and governance of tourism was examined, as well as its contribution to biodiversity conservation and development. In-depth semi-structured interviews were used to get qualitative information from the main stakeholders. The study shows that tourism is perceived as an important sustainable alternative to mining, oil extraction and hydroelectric projects, which are currently seen as the main threats to conservation in the area. However, tourism in the Sumaco area also faces some problems, which are related to the lack of adequate management and governance strategies, the worst among them being illegality and informality triggering uncontrolled competition, lowering of prices, and decrease in the quality of services. Altogether, these factors could ultimately lead to the overall decline of the destination. To improve the sustainable development of tourism, more efforts on coordination between different sectors (e.g. environment, mining and oil, and tourism) and levels of governments (local, regional, and national) are needed.
Las celulasas han sido clasificadas como endoglucanasas responsables de degradar celulosa, lo que le proporciona gran importancia en los procesos de la cadena alimentaria. Las celulasas y enzimas relacionadas son utilizadas ampliamente en varios procesos industriales. La celulosa es utilizada como una fuente nutricional por varios organismos, inicialmente se pensaba que únicamente microorganismos podrían degradarla, pero en la actualidad se ha encontrado celulasas en varios grupos de animales. En este trabajo, presentamos la detección de celulasas en extractos obtenidos del camarón Litopenaeus vannamei. En los ensayos se utilizaron individuos adultos y de los diferentes subestadios de L. vannamei colectados en los estanques de cría de las camaroneras de la Península de Santa Elena y Muisne, en las provincias de Santa Elena y Esmeraldas, respectivamente. Los hepatopáncreas, los estadios larvarios y los intestinos fueron homogeneizados en un homogeneizador Braun-Melsungen. Para la identificación de la celulasa, se utilizó como sustrato carboximetil celulosa (CMC) de mediana viscosidad. Para medir su actividad se añadió ácido 3,5 dinitrosalicílico (DNS). La actividad de la celulasa se determinó en base en la cantidad de los grupos reductores liberados. Para intentar determinar el origen sea endógeno o microbiano de las celulasas identificadas, se sometieron las muestras de adultos a antibióticos. En el subestadio zoea 3, se identificó una celulasa con un rango de pH óptimo entre pH 6.5 y pH 9.5.
Studies of highly migratory species that increase our understanding of the dynamics of genetic diversity, migratory routes, and genetic connectivity are essential for informing conservation actions. Genetic data for green turtles Chelonia mydas from Ecuador have only been available from Galápagos Islands (GPS) rookeries, but not from foraging aggregations. Furthermore, green turtles from habitats associated with mainland Ecuador (Machalilla National Park; MNP) have not been sampled. To assess the genetic relationships between nesting and foraging aggregations from these 2 regions and other regional populations, the mitochondrial DNA (mtDNA) control region was sequenced from 133 turtles. Conventional FST (haplotype frequency) and ΦST (sequence-based) values were low and non-significant between Ecuadorian rookeries, suggesting high connectivity between these sites located ca. 1000 km apart. Mixed stock analysis (MSA) indicated a dominant (>94%) GPS-MNP contribution to both foraging grounds, with small and nearly negligible contributions from other rookeries in the region (e.g. Costa Rica and Mexico). While orphan haplotypes were not included in the MSA because their rookery of origin is not known, their close genetic relationships to Western and Central Pacific mtDNA clades suggests that a relatively large percentage of turtles at the combined foraging sites (>10%) have been involved in transoceanic migration events. The genetic links between GPS and MNP C. mydas nesting populations revealed by our study highlight the need to incorporate the nesting populations from coastal Ecuador in more comprehensive future conservation planning.
Background: Trypanosoma cruzi, causative agent of Chagas disease, displays high intraspecific genetic diversity: six genetic lineages or discrete typing units (DTUs) are currently recognized, termed TcI through TcVI. Each DTU presents a particular distribution pattern across the Americas, and is loosely associated with different transmisión cycles and hosts. Several DTUs are known to circulate in Central America. It has been previously suggested that TcI infection is benign and does not lead to chronic chagasic cardiomyopathy (CCC). Findings: In this study, we genotyped T. cruzi parasites circulating in the blood and from explanted cardiac tissue of an El Salvadorian patient who developed reactivation Chagas disease while on immunosuppressive medications after undergoing heart transplant in the U.S. as treatment for end-stage CCC. Parasite typing was performed through molecular methods (restriction fragment length polymorphism of polymerase reaction chain amplified products, microsatellite typing, maxicircle sequence typing and low-stringency single primer PCR, [LSSP-PCR]) as well as lineage-specific serology. We show that the parasites infecting the patient belong to the TcI DTU exclusively. Our data indicate that the parasites isolated from the patient belong to a genotype frequently associated with human infection throughout the Americas (TcIDOM). Conclusions: Our results constitute compelling evidence in support of TcI DTU’s ability to cause end-stage CCC and help dispel any residual bias that infection with this lineage is benign, pointing to the need for increased surveillance for dissemination of this genotype in endemic regions, the USA and globally.
The spermatozoa of representatives of three Neotropical frog subfamilies, Leiuperinae, Leptodactylinae and Paratelmatobiinae, were observed using Transmission Electron Microscopy, with the aim of identifying ultrastructural traits that provide insights into the phylogenetic relationships among these anurans, which are currently unclear. In the leiuperines, spermatozoa of Physalaemus albifrons, P. cicada, P. deimaticus and P. feioi were characterized by an acrosomal vesicle covering the subacrosomal cone that was not observed in the spermatozoa of Physalaemus centralis and P. cuvieri. The tail of the spermatozoa of P. albifrons, P. centralis, P. cicada, P. cuvieri, P. deimaticus, and P. feioi presented a long undulating membrane, whereas Engystomops petersi and E. freibergi, which form a sister clade to Physalaemus, had an axial ﬁber, which were absent in Physalaemus. Other leiuperine, E. puyango had an abaxonemal bulb-like swelling distally to the paraxonemal rod, which were also absent in Physalaemus. These differences support the revalidation of Engystomops as a true taxon, distinct from Physalaemus. The tail of the spermatozoa of E. petersi and E. freibergi was similar to that of Paratelmatobius poecilogaster (Paratelmatobiinae). The spermatozoa of Leptodactylus natalenis (Leptodactylinae) had undulating membrane and axial ﬁber, in contrast with Adenomera marmorata, which lacked these structures. Morphological differences between A. marmorata and L. natalensis sperm cells appeared to validate the allocation of A. marmorata into a genus distinct from Leptodactylus. Overall, dissimilarities in the spermatozoa of the leptodactylids provided an important phylogenetic signal for the understanding of their taxonomic relationships.
The Andean uplift is recognized as one of the most important events shaping the Neotropical biota. Previousphylo genetic reconstructions of Nasa, a mostly tropicalAndean genus, have been unable to address its historical biogeography or ancestral character estimations in detail due to insucient sampling and phylogenetic resolution. The main goal of the present study is to provide an expanded and highly resolved phylogenetic reconstruction of the genus to address these questions. We were able to sequence 87 of the 125 taxa (species and subspecies) of and is composed of Central Andean species. The remaining three clades are more widely distributed, found also in the Amotape-Huancabamba Zone (AHZ) and the northern Andes. Our morphological analyses were able to identify plausible phylogenetic a nities of most Nasa spp. For which molecular data are unavailable, with three of the morphological clusters composed mostly by species of three well-supported clades (Clades II, III and IV). Historical biogeography indicates that Nasa has a history spanning 50 Myr, its early events predating most of the undergrowth habitats took place. This coincides with renewed uplift that increased the complexity of the abiotic
Climate induced species range shifts might create novel interactions among species that may outweigh direct climatic effects. In an agricultural context, climate change might alter the intensity of competition or facilitation interactions among pests with, potentially, negative consequences on the levels of damage to crop. This could threaten the productivity of agricultural systems and have negative impacts on food security, but has yet been poorly considered in studies. In this contribution, we constructed and evaluated process-based species distribution models for three invasive potato pests in the Tropical Andean Region. These three species have been found to co-occur and interact within the same potato tuber, causing different levels of damage to crop. Our models allowed us to predict the current and future distribution of the species and therefore, to assess how damage to crop might change in the future due to novel interactions. In general, our study revealed the main challenges related to distribution modeling of invasive pests in highly heterogeneous regions. It yielded different results for the three species, both in terms of accuracy and distribution, with one species surviving best at lower altitudes and the other two performing better at higher altitudes. As to future distributions our results suggested that the three species will show different responses to climate change, with one of them expanding to higher altitudes, another contracting its range and the other shifting its distribution to higher altitudes.
Clonal propagation becomes more abundant with increasing altitudes as environmental conditions worsen. To date, little attention has been paid to the way in which clonal propagation affects genetic diversity and the ﬁne-scale spatial genetic structure (FSGS) of clonal alpine trees. An AFLP study was undertaken to quantify the clonal and genetic diversity and FSGS of the vulnerable treeline species Polylepis reticulata in Ecuador. We successfully genotyped 32 and 75 ramets within 4 m 9100 m (coarse scale) and 4 m 94 m (ﬁne scale) transects of one population, respectively. Higher genotypic diversity was detected at the coarse scale than at the ﬁne scale, while lower genetic diversity was detected for P. reticulata than other Polylepis spp. at both scales. Signiﬁcantly stronger FSGS was detected at the ramet level than the genet level for P. reticulata within a spatial distance of 3 m. The studied P. reticulata population showed pronounced FSGS (Sp = 0.012 at the genet level, a statistic reﬂecting declining pairwise kinship with distance) revealed restricted gene dis- persal, which implies restricted seed dispersal for this population, assuming pollen ﬂow is as extensive as that described for other wind- pollinated tree species. Our results revealed that clonal diversity is a function of both sample size and the spatial scale of the sampling area. The ﬁndings highlights that clonal propagation has affected FSGS within a spatial distance of 3 m for this species.
Background: Determining the source of malaria outbreaks in Ecuador and identifying remaining transmission foci will help in malaria elimination efforts. In this study, the genetic signatures of Plasmodium falciparum isolates, obtained from an outbreak that occurred in northwest Ecuador from 2012 to 2013, were characterized. Methods: Molecular investigation of the outbreak was performed using neutral microsatellites, drug resistance markers and pfhrp2 and pfhrp3 genotyping. Results: A majority of parasite isolates (31/32) from this outbreak were of a single clonal type that matched a clonal lineage previously described on the northern coast of Peru and a historical isolate from Ecuador. All but one isolate carried a chloroquine‑resistant pfcrt genotype and sulfadoxine‑ and pyrimethamine‑sensitive pfdhps and pfdhfr genotypes. Pfmdr1 mutations were identified in codons 184 and 1042. In addition, most samples (97 %) showed presence of pfhrp2 gene. Conclusions: This study indicates that parasites from a single clonal lineage largely contributed to this outbreak and this lineage was found to be genetically related to a lineage previously reported in the Peruvian coast and historical Ecuadorian parasites.
Background Chagas disease is endemic to the southern Andean region of Ecuador, an area with one of the highest poverty rates in the country. However, few studies have looked into the epidemiology, vectors and transmission risks in this region. In this study we describe the triatomine household infestation in Loja province, determine the rate of Trypanosoma cruzi infection in triatomines and study the risk factors associated with infestation. Methodology/Principal Findings An entomological survey found four triatomine species (Rhodnius ecuadoriensis, Triatoma carrioni, Panstrongylus chinai, and P. rufotuberculatus) infesting domiciles in 68% of the 92 rural communities examined. Nine percent of domiciles were infested, and nymphs were observed in 80% of the infested domiciles. Triatomines were found in all ecological regions below 2,200 masl. We found R. ecuadoriensis (275 to 1948 masl) and T. carrioni (831 to 2242 masl) mostly in bedrooms within the domicile, and they were abundant in chicken coops near the domicile. Established colonies of P. chinai (175 to 2003 masl) and P. rufotuberculatus (404 to 1613 masl) also were found in the domicile. Triatomine infestation was associated with surrogate poverty indicators, such as poor sanitary infrastructure (lack of latrine/toilet [w = 0.95], sewage to environment [w = 1.0]). Vegetation type was a determinant of infestation [w = 1.0] and vector control program insecticide spraying was a protective factor [w = 1.0]. Of the 754 triatomines analyzed, 11% were infected with Trypanosoma cruzi and 2% were infected with T. rangeli.
The search for sensitive and rapid analytical techniques for the determination of natural antioxidants is an area in constant growth due, among other aspects, to the complexity of plant matrices. In this study, silver nanoparticles prepared with the aqueous extract of Mimosa albida leaves were used to assess their polyphenolic content and antioxidant capacity. Silver nanoparticles were characterized by different techniques. As a result, nanoparticles of 6.5 ± 3.1 nm were obtained. The total phenolic content in the extract was 1320.4 ± 17.6 mg of gallic acid equivalents GAE· 100 g−1 and in the nanoparticles 257.3 ± 5.1 mg GAE· 100 g−1. From the phenolic profile analyzed by ultra high-performance liquid chromatography (UPLC) with a diode-array detector (DAD), the presence of apigenin and luteolin in the plant extract is postulated. The antioxidant capacity measured by oxygen radical absorbance capacity ORAC-fluorescein assay was 86917 ± 6287 and 7563 ± 967 µmol ET g−1 in the extract and nanoparticles respectively. Electrochemical analysis by cyclic voltammetry (CV) confirmed the effective reduction capacity of the Mimosa albida leaves extract to reduce Ag ions to AgNPs and differential pulse voltammetry (DPV) suggested the presence of two main reducing agents in the extract. From this study, it was concluded that the aqueous extract of Mimosa albida contains reducing agents capable of synthesizing silver nanoparticles, which can be used in the phytochemical industry.
Food abundance influences the distribution of living organisms and is essential to their vital activities, including reproduction (Costa, 2009). Global climate variation has influenced prey availability, through changes in environmen- tal factors, with cascading effects in marine ecosystems (Doney et al., 2012). Some effects of climate variability have been observed in the western Antarctic Peninsula (WAP) region. Changes in species composition at the base of the food web, with an increase in the abundance of the small cryptophytes to the detriment of the larger diatoms, have been observed in tandem with warming in the region and consequent changes in ice coverage area and timing of the seasonal cycle (e.g., Mendes et al., 2018; Moline et al., 2004; Schofield et al., 2017). These changes may cascade up the food web and negatively affect the recruit ment and abundance of Antarctic krill (Euphausia superba, hereafter krill) as it does not have the capacity to feed on the small cell size cryptophytes (e.g., Moline et al., 2004). Krill has a vital role in the Southern Ocean ecosystem (e.g., Laws, 1985), as it is the main prey item of many species of penguins, seals, and whales in the region (e.g., Botta et al., 2017; Herr et al., 2016; Nowacek et al., 2011; Reid et al., 2005). Therefore, it is expected that variations in the food web, and particularly in krill abundance, will have consequences for many predator species and the ecosystem as a whole (e.g., Doney et al., 2012; Loeb et al., 2009; Montes-Hugo et al., 2009; Schofield et al., 2017; Seyboth et al., 2017).
Photovoltaic energy presents environmental advantages; however, these advantages are limited by the cost of manufacturing solar cells and in many cases, scarce or dangerous materials are incorporated. Therefore, the use of natural dyes from mortiño (Vaccinium floribundum) as sensitizers in solar cells is proposed. The dyes were extracted by maceration in acidified methanol (HCl, citric acid and trifluoroacetic acid TFA) and were characterized by High-Performance Liquid Chromatography (HPLC), Thin-Layer Chromatography (TLC) and spectrometric methods (UV-Vis, IR and MS-MALDI). The construction and characterization of cells were in standard conditions. The study confirms that pigments in mortiño are flavonoids of the anthocyanidin group as: cyanidin-3-galactoside, and cyanidin-3-arabinoside. The efficiency of solar cells was between 0.18–0.26%; the extraction with TFA in methanol leads to the best performance. Although they have low power conversion efficiency, mortiño dyes could be an alternative to artificial sensitizers for solar cell technologies because they are harmless and abundant substances.
Thiosulfate leaching combined with ion-exchange resins is an innovative alternative for gold recovery. According to the properties of activated carbon, it could replace resins in the gold recovery process, improve efficiency, and reduce operating cost. In this research, the adsorption process of gold thiosulfate complex on thiol-modified activated carbon was studied. Thioglycolic acid (ATG) was impregnated in activated carbon, and its adsorption ability was tested with synthetic solutions of gold and sodium thiosulfate (Au 10 mg·L-1, Na2S2O3 0.1 mol·L-1, pH = 10.0). Carbon was characterized by infrared spectroscopy, SEM-EDS, PZC titration, hardness number measures, and proximal analysis. Synthetic solutions were also characterized by UV-vis spectroscopy and cyclic voltammetry. The percentage of volatile material increased from 10.0 to 13.9% due to the impregnation process of ATG. Infrared spectra show characteristic bands of C-H, S-H, and C-S bonds. In the adsorption tests, the ATG-impregnated carbon achieved 91% of gold recovery, while the same amount of ATG in the liquid phase stirred with unmodified activated carbon reached 90% of gold recovery. The 44.9% of gold recovered with activated carbon impregnated with ATG was eluted with sodium cyanide ([NaCN] = 0.2 mol·L-1; [NaOH] = 0.25 mol·L-1; [CH3CH2OH] = 30% V/V; pH = 12.0; t = 24 h). These results suggest the gold transferred from the thiosulfate complex to a new gold thiolate complex.
The aim of the present study was to investigate the profile of Ecuadorians who died by suicide during 2011. The National Mortality Study of 2011 was used in order to investigate the variables: sex, age, marital status, area of residence, natural region, level of instruction, ethnic self-identification, pregnancy and types of suicide. A descriptive analysis, a multiple correspondence analysis and a hierarchical classification were realized. The analysis showed that the majority of the Ecuadorians who died by suicide were men, singles and married, they were living in urban areas, in the mountain range and coast region, they had attended Primary or Secondary education and died by hanging, strangulation and suffocation or by exposure to pesticides, other chemicals and noxious substances.
Wheat stem rust is a devastating disease that has incited severe epidemics resulting in extreme yield losses over the past century. Stem rust infection in plots of wheat line UC11075, known to carry the Sr38 resistance gene, was unusual and severe in February 2016 in a nursery at the Instituto Nacional de Investigaciones Agropecuarias Austro station near Cuenca, Ecuador. Stems with heavy infection by Puccinia graminis f. sp. tritici (Pgt) were sent for genotyping in labs at Ottawa, ON and St. Paul, MN, and for phenotyping at Morden, MB. None of the samples received directly from the field had viable spores, but genotyping was done in Ottawa and St. Paul using DNA extracted from spores or infected plant materials killed in ethanol. DNA was extracted using the OmniPrep™ kit (GBiosciences,St. Louis, MO).
Se conoce muy poco sobre las especies (su taxonomía y biogeografía) que interactúan en el proceso de descomposición de cadáveres en el Ecuador. Aquí presentamos los primeros datos de la entomofauna cadavérica, en especial moscas y coleópteros (Insecta: Diptera, y Coleoptera) presente en Pichincha, Ecuador. Para lograr el objetivo, se usaron cobayos como cebo en tres diferentes lugares: Nayón, Quito y Otongachi. Los cobayos sacrificados fueron colocados en jaulas metálicas por 30 días, donde se obtuvo un total de 41 especies para los tres sitios de muestreo. La composición de especies varía según el lugar debido a las condiciones específicas que ofrece cada lugar como son la vegetación, las condiciones meteorológicas y el tipo de suelo.
En el presente trabajo se describen cuatro miembros nuevos del grupo Drosophila repleta capturados en dos bosques nublados del Ecuador. Las nuevas especies fueron agrupadas dentro del subgrupo D. fasciola basados en el patrón de pigmentación del tórax y la morfología de la genitalia masculina. Drosophila inti sp. nov., D. nigua sp. nov. y D. yambe sp. nov. fueron capturadas con trampas de banano, mientras que D. carvalhoi sp. nov. fue recolectada en inflorescencias de Anthurium sp. La pigmentación del abdomen y la forma del edeago de D. nigua sp. nov., D. yambe sp. nov. y D. carvalhoi sp. nov. indicarían que están relacionadas entre ellas, mientras que D. inti sp. nov. sería más cercana a D. linearepleta Patterson & Wheeler, 1942.
Se reporta el descubrimiento de tres especies nuevas de serpientes Synophis de las estribaciones orientales de los Andes tropicales en Ecuador y Perú. Todos los registros previos de S. bogerti del oriente ecuatoriano corresponden a S. bogerti sp. n., la cual ocurre entre 1000–1750 m a lo largo de gran parte de las estribaciones amazónicas de los Andes ecuatorianos. En contraste, Synophis zamora sp. n. se restringe al suroriente de Ecuador, incluyendo la Cordillera del Cóndor, entre 1543–1843 m. Synophis insulomontanus sp. n. es de las estribaciones orientales de los Andes del centro y norte del Perú, entre 1122–1798 m, y representa el primer registro de Synophis para este país. Todas las tres especies nuevas comparten en común una espina lateral larga en la base del cuerpo del hemipene. Un árbol molecular filogenético, basado en tres genes mitocondriales es presentado, incluyendo muestras de Diaphorolepis wagneri. Nuestro árbol apoya fuertemente a Synophis y Diaphorolepis como taxa hermanos, así como la monofilia de las tres especies descritas y de S. calamitus. La inclusión de Synophis y Diaphorolepis dentro de Dipsadinae, como hermanas a un clado que contiene a Imantodes, Dipsas, Ninia, Hypsiglena y Pseudoleptodeira también es apoyada.
Spiralia represents one of the main clades of bilaterally symmetrical metazoans (Bilateria). This group is of particular interest due to the remarkable conservation of its early developmental pattern despite of the high diversity of larval and adult body plans. Variations during embryogenesis are considered powerful tools to determine ancestral and derived characters under a phylogenetic framework. By direct observation of embryos cultured in vitro, we analyzed the early cleavage of the euopisthobranchs Aplysia cf. californica. We used tubulin immunocytochemistry to stain mitotic spindles during early cleavages, and followed each division with the aid of an autofluorescent compound inside yolk platelets, which differed from the characteristic pink-brownish pigment of the vegetal cytoplasm in zygotes and early embryos. We found that this species exhibits an unequal cleavage characterized by ooplasmic segregation, oblique inclination of mitotic spindles, and differences in size and positioning of the asters in relation to the cellular cortex. Furthermore, we detected asynchrony in cleavage timing between the two large macromeres C and D, which increases the number of cleavage rounds required to reach a particular cell stage in comparison to other spiralians. Here, we report the presence of a transient and previously undescribed U-shaped embryo in this species. The present detailed description of A. califórnica early development deviates considerably from stereotypical patterns described in other spiralians. Our observations demonstrate that early spiralian development can be more plastic than previously thought.
The ecosystem-level consequences of agricultural land use in Neotropical forests have not been fully studied. In areas like the Choco-Darien, conflict exists between the conservation of highly diverse ecosystems and the use of economically important production areas. Current agricultural practices involve complete deforestation, with consequent multiple effects on stream ecosystems. To address the issue of land use change in tropical rivers of Ecuador, we studied streams draining 3 different land use types in the Mashpi River drainage (Ecuadorian Choco): (1) pristine montane cloud forest, (2) organic farms that included forest patches, and (3) palmito (Bactris gasipaes) production land with extensive use of the insecticide endosulfan and the herbicide glyphosate. We sampled macroinvertebrates (quantitative and qualitative samples) and periphyton, and measured environmental variables during dry and wet seasons, and found a direct relationship between the decline of certain macroinvertebrate groups (e.g., Anacroneuria, Hyallela) and the type of land use. Furthermore, we found that species loss in streams draining organic farms was negligible. Species richness of macroinvertebrates was considerably lower in palmito monoculture farmlands than in the other 2 types of land use. Stream communities of the Mashpi drainage area have been transformed by human agricultural disturbances, and urgent changes to land management practices are necessary.
Elysia diomedea , otherwise known as the “Mexican dancer”, aries in adult size and color across its geographical distribution in Ecuador. Because of morphological variation and the absence of genetic information for this species in Ecuador, we analyzed mtDNA sequences in three populations (Ballenita, La Cabuya, and Mompiche) and confirmed that individuals from the three locations belonged to E. diomedea and that there was no population structure that could explain their morphological differences. Next, we analyzed general aspects about the reproductive biology and embryology of this species. Live slugs from the Ballenita population were maintained and reproduced ex situ. Egg ribbons and embryos were fixed and observed by brightfield and confocal microscopy. We observed a single embryo per capsule, 98 embryos per mm2 of egg ribbon, and compared the cleavage pattern of this species to that of other heterobranchs and spiralians. E.diomedea early development was characterized by a slight unequal first cleavage, occurrence of a 3-cell stage in the second cleavage, and the formation of an enlarged second quartet of micromeres. We observed clear yolk bodies in the egg capsules of some eggs ribbons at early stages of develop-ment. Both reproductive and embryological characteristics, such as presence of stomodeum in the larva, and ingestion of particles after hatching confirmed the planktotrophic veliger larvae of this species, consistent with the majority of sacoglossans from the Eastern and Northeast Pacific Oceans..
El presente es un estudio computacional de la interacción de diferentes antinflamatorios no esteroideos con la enzima Ciclooxigenasa 2 (COX-2). El objetivo fue determinar la afinidad con la cual los inhibidores estudiados se enlazan con el sitio activo de la enzima y calcular la eficiencia de enlace de los mismos. Además, comprobar la aplicabilidad de los métodos de acoplamiento molecular, en la determinación de moléculas prometedoras, que aceleren los estudios de descubrimiento de nuevos fármacos. Se utilizaron métodos de dinámica molecular, para modelar las interacciones entre la enzima COX-2 y los sustratos celecoxib, diclofenaco, etoricoxib, indometacina, ibuprofeno, meloxicam y naproxeno, por medio del programa Autodock VINA. Los resultados muestran que la molécula que posee una mayor afinidad con la COX-2 es el celecoxib, con una energía de enlace de -10.8 kcal/mol y una constante de equilibrio Ki de 1.21x10-8 M. El ibuprofeno y el naproxeno son las moléculas con mayor eficiencia de enlace, con un valor mayor a -0.48 kcal/mol/átomos (no hidrógeno). Esto demuestra que una molécula que tiene una buena afinidad, no necesariamente debe tener una buena eficiencia de enlace. Estos valores dan una pauta para poder elegir la mejor molécula para inhibir la enzima COX-2 y en casos de descubrimiento de fármacos, la molécula idónea para invertir en su mejoramiento y optimización, para convertirla en un fármaco aprobado.
Background Management and conservation of biodiversity requires adequate species inventories. The Yasuní National Park is one of the most diverse regions on Earth and recent studies of terrestrial vertebrates, based on genetic evidence, have shown high levels of cryptic and undescribed diversity. Few genetic studies have been carried out in freshwater fishes from western Amazonia. Thus, in contrast with terrestrial vertebrates, their content of cryptic diversity remains unknown. In this study, we carried out genetic and morphological analyses on characin fishes at Yasuní National Park, in eastern Ecuador. Our goal was to identify cryptic diversity among one of the most speciose fish families in the Amazon region. This is the first time that genetic evidence has been used to assess the species content of the Napo Basin, one of the richest regions in vertebrate diversity. Results Phylogenetic analyses of partial mitochondrial 16S ribosomal RNA gene (*600 pb) DNA sequences from 232 specimens of the family Characidae and its closest groups revealed eight candidate new species among 33 species sampled, representing a 24% increase in species number. Analyses of external morphology allowed us to confirm the species status of six of the candidate species. Conclusions Our results show high levels of cryptic diversity in Amazonian characins. If this group is representative of other Amazonian fish, our results would imply that the species richness of the Amazonian ichthyofauna is highly underestimated. Molecular methods are a necessary tool to obtain more realistic inventories of Neotropical freshwater fishes.
Aims We studied diversity, patterns of endemism and turnover of vegetation composition in dry inter-Andean valleys (DIAVs) where little is known about the influence of the abiotic drivers controlling plant species composition and occurrences, and the life forms that contribute most to α- and β-diversity, respectively. This study was focused on DIAVs located in the highlands (800–2800 m) around the Equator (1°N–5°S). The following questions were addressed: (i) what differences exist between endemic and non-endemic species in terms of species number, frequency and abundance? (ii) are patterns of α- and β-diversity correlated with latitude? (iii) what are the major environmental drivers controlling spatial patterns in species composition and occurrence? Methods We established 63 transects of 5 × 100 m in areas with DIAV vegetation, impacted as little as possible by human activities. In each transect, all mature trees and shrubs were identified and counted to determine their density. The coverage of terrestrial herbs was estimated. Generalized additive models were used to quantify the relationship between α- and β-diversity with latitude. To record α-diversity, we used the exponential Shannon index. The Sørensen index was used to measure β-diversity or species turnover. We used canonical correspondence analysis to determine species composition and generalized linear mixed models to quantify simultaneously the determinants of species occurrence across species and sites. The models were evaluated using the Akaike information criterion. All analyses were run separately for trees, herbs and shrubs.
El hormigón es uno de los materiales más usados en el área de construcción. Debido al uso diario de este material se realizó el estudio del envejecimiento del hormigón simple y del hormigón armado para prevenir futuras afectaciones a este tipo de materiales. Se ubicaron muestras de hormigón en una cámara de simulación climática en la que se controlaron las condiciones de humedad, temperatura y radiación de acuerdo a un modelo multivariable de los parámetros mencionados para simular el envejecimiento acelerado de los materiales. De esta manera se logró representar la degradación acelerada que sufrirían los materiales en la ciudad de Quito en 0, 5, 10, 15 y 20 años de exposición ambiental. Se emplearon técnicas gravimétricas, técnicas volumétricas, y la técnica de espectrofotometría de absorción atómica. Todos los resultados obtenidos fueron tabulados y graficados para visualizar su variación y tendencia en función del tiempo de exposición. El análisis más destacado fue el de la humedad, ya que presentó una tendencia de aumento y disminución con valores que varían entre 2,17 % y 3,37 % para el hormigón simple y 1,21 % y 2,32 % en el caso del hormigón armado, lo cual se debe a la evaporación del agua por las temperaturas elevadas. Otro análisis importante fue el equilibrio carbonato-bicarbonato debido al paso de iones hidronio (H+) que provocó un cambio de pH en el medio, y los óxidos de hierro que variaron significativamente por la presencia de un refuerzo de hierro en el hormigón armado con valores de 2,26 % a 7,23 % con respecto al hormigón simple que presentó valores de 0,89 % a 5,48 %. Se concluyó que sí existieron cambios en la composición química del hormigón simple y del hormigón armado al pasar los años.
Genome size (or C-value) can present a wide range of values among eukaryotes. This variation has been attributed to differences in the ampliﬁcation and deletion of different noncoding repetitive sequences, particularly transposable elements (TEs). TEs can be activated under different stress conditions such as interspeciﬁc hybridization events, as described for several species of animals and plants. These massive transposition episodes can lead to considerable genome expansions that could ultimately be involved in hybrid speciation processes. Here, we describe the effects of hybridization and introgression on genome size of Drosophila hybrids. We measured the genome size of two close Drosophila species, Drosophila buzzatii and Drosophila koepferae, their F1 offspring and the off spring from three generations of backcrossed hybrids; where mobilization of up to 28 different TEs was previously detected. We show that hybrid females indeed present a genome expansion, especially in the ﬁrst backcross, which could likely be explained by transposition events. Hybrid males, which exhibit more variable-C values among individual soft he same generation, do not presentan increased genome size. Thus, we demonstrate that the impact of hybridization on genome size can be detected through ﬂow cytometry and is sex-dependent.
Consumers have considered organic crops more beneficial to health and the environment as opposed to con-ventional crops. The following review aims to compare the major nutrients and mineral content in organic and conventional tomatoes. As such, articles related to the comparison of organic and conventional tomato crops were selected, as well as articles in which nutrient and/or mineral content were determined. Four research groups were formed based on their hypotheses. The quality of each study was evaluated considering the sta-tistical tools used to determine the results’ significance. Result ranges were compared to analyze the variation in the individual nutrient and mineral content in each study. No objective evidence was found that organic crops are nutritionally better than conventional crops; in both cases, results were within similar ranges. For conven-tional and organic tomatoes (fresh weight), the respective concentration ranges were 1.00–63.8 mg/100 g and 10.7–40.0 mg/100 g for ascorbic acid, 0.02–337.0 mg/100 g and 0.44–422 mg/100 g for lycopene, and 0.0058–4.44 mg/100 g and 0.0061–3.90 mg/100 g for β-carotene. For polyphenol and mineral content, the re-sults varied depending on farming technique. Finally, aspects related to environmental protection help organic products achieve better market positioning.
Background: Environment may have a key role in the development of the immune system in childhood and environmental exposures associated with rural residence may explain the low prevalence of allergic and autoimmune diseases in the rural tropics. We investigated the effects of urban versus rural residence on the adaptive immune response in children living in urban and rural areas in a tropical region of Latin America. Methods: We recruited school children in either rural communities in the Province of Esmeraldas or in urban neighborhoods in the city of Esmeraldas, Ecuador. We collected data on environmental exposures by questionnaire and on intestinal parasites by examination of stool samples. Peripheral blood leukocytes (PBLs) in whole blood were stimulated with superantigen, parasite antigens and aeroallergens and IFN-γ, IL-5, IL-10, IL-13, and IL-17 were measured in supernatants. Results: We evaluated 440 school children; 210 living in rural communities and 230 in the city of Esmeraldas. Overall, urban children had greater access to piped water (urban 98.7 % vs. rural 1.9 %), were more likely to have a household bathroom (urban 97.4 % vs. rural 54.8 %), and were less likely to be infected with soil-transmitted helminth infections (urban 20.9 % vs. rural 73.5 %). Generally, detectable levels of cytokines were more frequent in blood from children living in urban than rural areas.
Glacier retreat is a worldwide phenomenon with important consequences for the hydrological cycle and downstream ecosystem structure and functioning. To determine the effects of glacier retreat on aquatic communities, we conducted a 4-year ﬂow manipulation in a tropical glacier-fed stream. Compared with an adjacent reference stream, meltwater ﬂow reduction induces signiﬁcant changes in benthic fauna community composition in less than 2 weeks. Also, both algal and herbivore biomass signiﬁcantly increase in the manipulated stream as a response to ﬂow reduction. After the ﬂow reduction ceased, the system requires 14–16 months to return to its pre-perturbation state. These results are supported by a multi-stream survey of sites varying in glacial inﬂuence, showing an abrupt increase in algal and herbivore biomass below 11% glacier cover in the catchment. This study shows that ﬂow reduction strongly affects glacier-fed stream biota, preﬁguring profound ecological effects of ongoing glacier retreat on aquatic systems.
Mammalian inner ear and fish lateral line sensory hair cells (HCs) detect fluid motion to transduce environmental signals. Actively maintained ionic homeostasis of the mammalian inner ear endolymph is essential for HC function. In contrast, fish lateral line HCs are exposed to the fluctuating ionic composition of the aqueous environment. Using lineage labeling, in vivo time-lapse imaging and scRNA-seq, we discovered highly motile skin-derived cells that invade mature mechanosensory organs of the zebrafish lateral line and differentiate into Neuromast-associated (Nm) ionocytes. This invasion is adaptive as it is triggered by environmental fluctuations. Our discovery of Nm ionocytes challenges the notion of an entirely placodally derived lateral line and identifies Nm ionocytes as likely regulators of HC function possibly by modulating the ionic microenvironment. Nm ionocytes provide an experimentally accessible in vivo system to study cell invasion and migration, as well as the physiological adaptation of vertebrate organs to changing environmental conditions.
Background: Maternal geohelminth infections during pregnancy may protect against allergy development in childhood. Objective: We sought to investigate the effect of maternal geohelminths on the development of eczema, wheeze, and atopy during the ﬁrst 3 years of life. Methods: A cohort of 2404 neonates was followed to 3 years of age in a rural district in coastal Ecuador. Data on wheeze and eczema were collected by means of questionnaire and physical examination at 13, 24, and 36 months of age. Atopy was measured based on skin prick test (SPT) reactivity to 9 allergens at 36 months. Maternal stool samples were examined for geohelminths by microscopy. Data on potential confounders was collected after birth by questionnaire. Results: Geohelminths were observed in 45.9% of mothers. Eczema and wheeze were reported for 17.7% and 25.9%, respectively, of 2069 (86.1%) children with complete follow-up to 3 years, and allergen SPT reactivity to any allergen was present in 17.2% and to house dust mite in 8.7%. Maternal geohelminth infections were not signiﬁcantly associated with eczema (adjusted odds ratio [OR], 1.26; 95% CI, 0.98-1.61), wheeze (adjusted OR, 1.02; 95% CI, 0.82-1.27), and SPT reactivity to any allergen (adjusted OR, 0.79; 95% CI, 0.61-1.01). In subgroup analyses maternal geohelminths were associated with a signiﬁcantly reduced risk of SPT reactivity to mite and other perennial allergens, and maternal ascariasis was associated with an increased risk of eczema and reduced risk of SPT reactivity to all allergens.
El aumento poblacional y el desarrollo tecnológico ha ocasionado una gran demanda energética, lo que ha dado paso a que varios grupos de investigación incursionen en la búsqueda de soluciones a corto y mediano plazo. El uso de tecnologías que permitan tratar aguas contaminadas y la generación simultánea de energía eléctrica surge como una alternativa viable para dar solución a este problema. En este documento se revisa el mecanismo para el tratamiento de agua residual y la generación de energía eléctrica simultánea, a través de sistemas combinados de humedales acoplados a celdas de combustible microbianas (CW-MFC, por sus siglas en inglés). El objetivo de esta revisión es describir los componentes y funcionamiento de los sistemas individuales CW y MFC, así como también del sistema combinado CW-MFC, los cuales han sido empleados en investigaciones recientes. Se exploran los principales estudios, relacionados con el material con el cual se construyen los electrodos, que generen mayor eficiencia energética y materiales filtrantes que beneficien el tratamiento del agua residual. Además, se presentan los desafíos en este ámbito de investigación. Los CW y las MFC son sistemas que combinados mejoran la eficiencia en el tratamiento de agua residual y a la vez permiten aprovechar la energía eléctrica que los microorganismos generan durante el proceso de oxidación de la materia orgánica.
Kinetic and environmental aspects related with the mineralization of a commercial glyphosate (GP) formulation in a pre-pilot-scale reactor were assessed. Assays were performed at an acidic pH using Na2SO4 as support electrolyte at five different current densities. GP removal can be achieved in 60 min and is not dependent on the applied current density; however, the reduction of organic carbon (TOC) and chemical oxygen demand (COD) from the sample evidence the impact of the limitations of mass transfer in aspects like energy consumption, effluent quality, and sustainability of the process. Assays at 120 and 240 mg L−1 revealed that it is feasible to improve the biodegradability of the effluent after 300 min of treatment using higher current densities (80 and 100 mA cm−2 ). At 360 mg L−1, neither the current density nor the time of treatment had an impact on the biodegradability of the effluent at all the assessed current densities. GP removal could have an environmental footprint (1.3 kg CO2 Eqv/kg TOC) in countries where the energy matrix depends on hydro-power. In countries where electricity is generated from non-renewable raw materials, like gas or coal, the emis-sions of greenhouse gasses (GHG) could increase 170% and 439%, respectively. The use of renewable energy sources, like wind power or solar, could reduce the GHG emission to 0.3 kg CO2 Eqv/kg TOC. The cost of treatment ranged between US$ 0.7 and 2.1 g TOC−1 removed; this variability is due to the selected energy source and the subsidies established in each country.
In this study, electro-oxidation (EOx) and in situ generation of ferrate ions [Fe(VI)] were tested to treat water contaminated with Blue BR dye (BBR) using a boron-doped diamond (BDD) anode. Two electrolytic media (0.1 M HClO4 and 0.05 M Na2SO4) were evaluated for the BDD, which simultaneously produced oxygen radicals (•OH) and [Fe(VI)]. The generation of [Fe(VI)] was characterized by cyclic voltammetry (CV) and the effect of different current intensity values (e.g., 7 mA cm−2, 15 mA cm−2, and 30 mA cm−2) was assessed during BBR degradation tests. The discoloration of BBR was followed by UV-Vis spectrophotometry. When the EOx process was used alone, only 78% BBR discoloration was achieved. The best electrochemical discoloration conditions were found using 0.05 M Na2SO4 and 30 mA cm−2. Using these conditions, overall BBR discoloration values up to 98%, 95%, and 87% with 12 mM, 6 mM, and 1 mM of FeSO4, respectively, were achieved. In the case of chemical oxygen demand (COD) reduction, the EOx process showed only a 37% COD reduction, whereas combining [Fe(VI)] generation using 12 mM of FeSO4 achieved an up to 61% COD reduction after 90 min. The evolution of reaction byproducts (oxalic acid) was performed using liquid chromatography analysis.
Research on nanomaterial exposure-related health risks is still quite limited; this includes standardizing methods for measuring metals in living organisms. Thus, this study validated an atomic absorption spectrophotometry method to determine fertility and bioaccumulated iron content in Drosophila melanogaster flies after feeding them magnetite nanoparticles (Fe3O4NPs) dosed in a culture medium (100, 250, 500, and 1000 mg kg−1). Some NPs were also coated with chitosan to compare iron assimilation. Considering both accuracy and precision, results showed the method was optimal for concentrations greater than 20 mg L−1. Recovery values were considered optimum within the 95–105% range. Regarding fertility, offspring for each coated and non-coated NPs concentration decreased in relation to the control group. Flies exposed to 100 mg L−1 of coated NPs presented the lowest fertility level and highest bioaccumulation factor. Despite an association between iron bioaccumulation and NPs concentration, the 500 mg L−1 dose of coated and non-coated NPs showed similar iron concentrations to those of the control group. Thus, Drosophila flies’ fertility decreased after NPs exposure, while iron bioaccumulation was related to NPs concentration and coating. We determined this method can overcome sample limitations and biological matrix-associated heterogeneity, thus allowing for bioaccumulated iron detection regardless of exposure to coated or non-coated magnetite NPs, meaning this protocol could be applicable with any type of iron NPs.
Se revisan los principales usos de la química forense en la investigación criminal y se exploran los posibles campos de acción en el Ecuador. Para este efecto, se delimita el alcance de la disciplina y se provee una breve descripción de las principales aplicaciones que esta tiene a nivel mundial. Luego, se exponen dos casos que han alcanzado notoriedad – y causado polémica- en los cuales se involucran directa o indirectamente las técnicas forenses. Finalmente, se exponen los escenarios de interés nacional en los cuales la química forense podría ser de utilidad y las formas en las cuales el país puede contribuir al desarrollo de esta ciencia.
The environmental flow is a management tool to mitigate the impact of a dam on ecosystems. The Ecuadorian law requires that the environmental flow remains 10% of mean annual flow in old hydroelectric stations, however advances on this area suggest this is not adequate. The objective of this research was to assess the impacts of a 10% release and establish environmental flow recommendations in the Macha´ngara and Chulco rivers which have been dammed by the Chanlud and El Labrado hydroelectric plants, in the watershed of the Macha´ngara River (southern Ecuador). During twelve months physical and chemical parameters, and aquatic macro-invertebrates were recorded. The analysis found significant differences in some parameters, indicating a decline in ecosystem condition and relations were found between the flow, the diversity of macro-invertebrates and the concentration of dissolved O2 (DO). However, determining whether these impacts are unacceptable is difficult because Ecuador does not have established criteria for required ecological condition. This deterioration in ecological conditions can be minimized by applying more modern methods of environmental flow assessment such as the basic flow methodology (BFM) that allows the variability of the river flow. In the Macha´ngara River (3000–4000 m a.s.l.) an environmental flow of 27–51% of the mean annual flow for the rainy season and 29–42% in the dry season were determined by using BFM. Whereas for the Chulco River (3000–4000 m a.s.l.) the environmental flow was 15– 45% of the mean annual flow for the rainy season and 15–36% for the dry season.
Se presenta un estudio espectroscópico computacional del ibuprofeno y sus precursores químicos isobutilbenceno y 4-isobutilacetofenona. En la investigación se utilizó el programa de modelamiento electrónico estructural GAUSSIAN 03. Se realizó la optimización molecular de todas las estructuras de interés y se calcularon las propiedades espectroscópicas de resonancia magnética nuclear (RMN). Los espectros computacionales obtenidos fueron comparados con los espectros experimentales citados en la literatura, demostrando ser muy similares. Las principales diferencias se deben al estado de agregación, ya que los cálculos computacionales son realizados en estado gaseoso, mientras que los obtenidos de la literatura se encuentran en soluciones deuteradas. Los espectros computacionales son comparables con los resultados obtenidos de la literatura, lo que comprueba la aplicabilidad de estos métodos en procesos de síntesis y diseño de nuevos compuestos químicos.
Las reacciones de sustitución nucleofílica de Vicarius, son una manera versátil de introducir sustituyentes en compuestos aromáticos deficientes de electrones. El propósito de este estudio fue establecer escalas teóricas absolutas de electrofilia, por medio de la aplicación de índices electrónicos definidos en la Teoría del Funcional de la Densidad, para clasificar una serie de 35 nitrobencenos sustituidos y analizar los patrones de reactividad de estas reacciones. Para el estudio, se eligieron nitrobencenos con varios sustituyentes en las posiciones orto, meta y para. Al aplicar el concepto de electrofilia global al nivel de teoría B3LYP/6-311G (d, p), se encontró una escala absoluta para cada posición de los sustituyentes, que se la relacionó con los valores σ de Hammett, para sustituyentes en las posiciones meta y para, obteniendo una relación lineal. Estos resultados concuerdan con la capacidad de estos sustituyentes de aceptar o ceder electrones, siendo los sustituyentes electroaceptores los que aumentan la electrofilia, y los electrodonadores los que la disminuyen.
Se presenta un estudio comparativo de los espectros infrarrojo (IR) y ultravioleta/visible (UV/VIS) de ibuprofeno, isobutilbenceno y 4-isobutilacetofenona obtenidos experimentalmente, con los calculados computacionalmente. La investigación constó de dos etapas. En la primera se realizó la síntesis experimental de ibuprofeno, donde se aislaron los precursores para el análisis. En la segunda fase, se utilizó el programa de modelamiento electrónico estructural GAUSSIAN 03, donde se obtuvo una optimización molecular de todas las estructuras de interés y sus propiedades espectroscópicas. Los espectros experimentales fueron comparados con los computacionales, obteniéndose ligeras diferencias, con porcentajes de error en bandas especíﬁcas, entre 2 y 28 % en los dos tipos de espectroscopía. La principal causa, puede ser el distinto estado de agregación en la que se encuentran las moléculas: estado líquido y sólido en el caso de los espectros experimentales, y estado gaseoso en el caso de los espectros computacionales. Los espectros computacionales son comparables con los obtenidos experimentalmente, demostrando ser bastante exactos. Esto comprueba la aplicabilidad de los métodos computacionales, en el proceso de síntesis y diseño de nuevos fármacos.
Numerous Neotropical rainforest species are distributed in both Amazonia and Central America, reﬂecting a rich history of biotic interchange between regions. However, some plant lineages are endemic to one region, due in part to the dispersal barrier posed by the Northern Andean Cordilleras and adjacent savannas. To investigate the role of biogeographic ﬁltering across the northern Andes in regional community assembly, we examined environmental tolerances, functional traits, and biogeographic distributions of 1000 woody plant species (trees, shrubs, lianas) locally co-occurring in forest plots in lowland Panama (542 species) and Amazonian Ecuador (667 species). High regional abundance was strongly predictive of the probability of being geographically widespread (i.e. present on both sides of the Andes). However, we also found that species with broad environmental tolerances (those that are able to inhabit high elevations and areas of low mean annual precipitation) were more likely to have a cross-Andean distribution even after accounting for regional abundance, suggesting that biogeographic ﬁltering for these traits has mediated cross-Andean dispersal. Regional abundance and environmental tolerances were additionally associated with a suite of life-history traits related to high dispersal–colonization ability, but most traits reﬂecting dispersal–colonization ability were not predictive of biogeographic distribution. Our results highlight how the process of biogeographic ﬁltering, based primarily on environmental tolerances, has mediated regional-scale ﬂoristic assembly of Neo-tropical rainforests. e impacts of this process, which we term ﬁlter-dispersal assembly, are likely to be especially important to forests in Central America, where biotic interchange with Amazonia has heavily inﬂuenced regional community composition.
The European sturgeon is critically endangered and the French ex-situ conservation approach involves developing a captive stock to produce offspring for release to boost natural populations. The purpose of our study was to assess the effects of rearing environment before stocking on the survival, growth, and behavior of three-month-old sturgeons from two different crossings. Enriched rearing was designed to mimic the variability of the natural environment using river water, natural photoperiod, substrate, variable water current and depths. Traditional rearing was carried out with bare tanks, underground water, dark conditions, without current and at constant depth. Fish survival was determined monthly and growth was estimated weekly. Behavior was assessed with exploration and novel prey tests in solitary using video tracking. Results demonstrated that enriched condition resulted in bigger fish from the first month. Growth curve analysis revealed that enriched environment made both fish crossings grow in a similar manner. In contrast, crossings growth differed in traditional rearing which may reflect a genotype-environment interaction. Behavioral data highlighted that enriched-reared fish were slower to explore a new environment but more individuals engagedon doing so than traditional-reared fish. Results also showed that survival was high (>80 %) during all the trial. However, survival was lower during the second month in enriched environment. Our findings advocate for the integration of enriched rearing practices within the juvenile production for release in order to boost the performance linked to fitness. Stocking practices and life history research must work together to favor adaptive aquaculture approaches, which support species conservation.
The gymnophthalmid lizard clade Macropholidus, traditionally ranked as a genus, was recently defined by Torres-Carvajal and Mafla-Endara (2013) as the largest crown clade containing Macropholidus ruthveni Noble1921, but not Pholidobolus montium Peters 1863. This phylogenetic definition (de Queiroz and Gauthier, 1994) is based on a phylogenetic tree obtained from analyses of mitochondrial DNA nucleotide sequence data (Torres-Carvajal and Mafla-Endara, 2013), and is in conflict with previous non-phylogenetic definitions of both Pholidobolus and Macropholidus (Montanucci, 1973; Reeder, 1996) based on morphological data. In contrast to Pholidobolus, members of Macropholidus have a single transparent palpebral disc in the lower eyelid and lack a lateral fold between fore and hind limbs (Torres-Carvajal and Mafla-Endara, 2013). Macropholidus lizards occur between 800 and 3000 m within a region of relatively low-elevation mountains in the Andes of southern Ecuador and northern Peru, known as the Huancabamba Depression (Torres-Carvajal and Mafla-Endara, 2013). As defined by Torres-Carvajal and Mafla-Endara (2013), Macropholidus contains four species (M. annectens, M. ataktolepis, M. huancabambae, M. ruthveni) of which only M. annectens has been reported for Ecuador. Macropholidus ruthveni is currently known from both humid and dry Andean montane forests in northern Peru at elevations between 800-2500 m (Cadle and Chuna, 1995; P. Venegas pers. comm.). Herein, we present the first record of M. ruthveni for Ecuador, based on a male collected at Reserva Natural Tumbesia - La Ceiba, Zapotillo, Province of Loja in southwestern Ecuador (Fig. 1; S 4.2746, W 80.3158; WGS84; 477 m).
Introduced species are known to be potentially harmful and cause negative effects on native species and ecosystems. In addition, economic losses are common because of the occurrence and persistence of introduced species (Pimentel et al. 2001). Events of species introduction constitute one of the main drivers of biodiversity loss (Chapin et al. 2000; Didham et al. 2005). In some cases, non-native species constitute the cause for local or global changes in abundance, and of species composition (Kraus2015; Nuñez & Pauchard 2010). Thus, it becomes a big challenge to counteract the advance of introduced species, especially in megadiverse countries that are undergoing intensive economic development (Lövei et al. 2012).
Over a thousand extracts were tested for phenotypic effects in developing zebraﬁsh embryos to identify bioactive molecules produced by endophytic fungi. One extract isolated from Fusarium sp., a widely distributed fungal genus found in soil and often associated with plants, induced an undulated notochord in developing zebraﬁsh embryos. The active compound was isolated and identiﬁed as fusaric acid. Previous literature has shown this phenotype to be associated with copper chelation from the active site of lysyl oxidase, but the ability of fusaric acid to bind copper ions has not been well described. Isothermal titration calorimetry revealed that fusaric acid is a modest copper chelator with a binding constant of 4.4 9 105 M-1. These results shed light on the toxicity of fusaric acid and the potential teratogenic effects of consuming plants infected with Fusarium sp.
In montane systems, global warming may lead communities to disassemble by forcing organisms to shift their distributions to higher elevations or by causing the extinction of those that are unable to adapt. To predict which species are most at risk from environmental change, physiological responses to multiple factors must be measured in natural conditions at fine spatial and temporal scales. To examine the potential drivers of elevational distributions in tabanid flies, specimens were exhaustively sampled at three altitudes within a tropical montane cloud forest in Western Ecuador. Observed abundances were then correlated with seven environmental variables measured in situ. It was hypothesised that (1) tabanid distributions were significantly associated with particular environmental conditions measured in each altitudinal habitat, and (2) a greater proportion of lowland species were limited to a specific elevation than highland species. Most species occupied well‐defined altitudinal niches corresponding to optimal climatic conditions. Colder weather, higher daily temperature variability, and higher levels of moisture seemed to limit most species from establishing in high elevation sites of this mountainous ecosystem. Despite the high dispersal potential of tabanids within the study area, results suggest that most tabanid flies are limited to the subset of altitudes where their climatic requirements are satisfied.
Palmito (Bactris gasipaes var. gasipaes Kunth), the only native domesticated palm in the Neotropics, is used for its fruit, wood, and also for heart of palm. Ecuador is the largest exporter of palmito, with approximately 16,000 ha cultivated in 2009, representing 57% of the world’s market (Montúfar and Rosas 2013). During two visits in February and May 2014 to palmito farms in the province of Santo Domingo de los Tsáchilas in western Ecuador, scattered plants with bud rot symptoms were observed. The affected plants showed chlorotic spear leaves, with necrosis inside the base of the stem on the meristematic tissue and tested positive for Phytophthora spp. using ImmunoStrip tests (Agdia Inc. Elkhart, IN, USA). Infected meristem tissue was baited on surface sterilized papayas and kept between 20 to 25°C for 7 days (Torres et al. 2010).
Global biodiversity loss is creating a more urgent need to understand the role organisms play in ecosystem functioning and mechanisms of control. Decomposition of dead organic matter is a key ecological process that ensures soil formation, nutrient availability, and carbon sequestration. To gain understanding of how biodiversity and ecosystems function together to control leaf-litter decomposition processes in a tropical rain forest (Yasun ı National Park, Ecuador), we predicted the consequences of the decomposition process using a protocol in which we systematically disassemble the structural functionality of the soil macrofauna communities. We (1) describe the structure and function of the edaphic communities in detail and (2) explore the functional consequences of structural changes in these communities using a non-random exclusion experiment to simulate body size-related extinctions. To do this, we manipulated access of five size classes of soil invertebrates to eight types of plant leaf-litter resources. After measuring and identifying about 4400 soil individuals belonging to 541 morphospecies, 12 functional groups, and following the fate of about 2000 tree leaves in a 50-ha plot, we showed that (1) soil invertebrate communities were composed of a few common and many rare morphospecies that included mostly leaf-litter transformer groups, with the most morphospecies and the greatest abundance coming from Hymenoptera, Collembola, and Coleoptera; (2) our survey captured 63–74% of the total soil biodiversity of the study area (meaning there may be up to 860 morphospecies); (3) litter transformers covered the widest range of body volume, and all groups were evenly distributed at small and large spatial scales (i.e., we found no patterns of spatial aggregation); (4) changes in food web structure significantly altered biomass loss for only three of the eight leaf-litter treatments, suggesting the decomposition process was highly resistant to drastic changes such as size-biased biodiversity loss independent of resource quality. We conclude organic matter decomposition may depend on all non-additive effects that arise from multi-species interactions, including facilitation, interspecific interference competition, and top-down control that predators exert over detritivores at all body size ranges.
Background: 1,8-Cineole, a commercially important monoterpene, was identified as a fungal product. Results: The 1,8-cineole synthase was identified from a Hypoxylon fungal genome, and mutagenesis revealed a critical asparagine residue. Conclusion: The fungal 1,8-cineole synthase uses a mechanism similar to the plant version. Significance: This is the first identified fungal monoterpene synthase and may facilitate future terpene synthase identification and production.
Mormoops megalophylla is a cave-dwelling bat distributed from southern United States across Central America to northern Peru. Its con¬servation status at a global level is of Least Concern, according to the IUCN Red List of Threatened Species; in Ecuador, however, it is included under the Vulnerable category due to the threats faced by the only two viable populations known. Individuals from each locality (Carchi and Pichincha) were captured and marked. The D-loop of the mitochondrial control region was obtained from wing membrane tissue samples, in order to analyze the geographic distribution of nucleotide and haplotype diversity of the populations, as well as gene flow between them. The molecular variation within and between populations was evaluated through a molecular variance analysis. A high haplotype diversity and a low nucleotide diversity were observed. The gene-flow estimator revealed that Carchi and Pichincha make up a single population coming from a single lineage. The network of haplotypes indicated that those with the highest frequency are shared in both localities; the largest number of unique haplotypes, however, was observed in Pichincha. The high haplotype diversity and low nucleotide diversity values in Ecuador are due to the fact that the ghost-faced bat populations may have experienced a fast-growing period from a low effective population size, with sufficient time to accumulate haplotype diversity, but insufficient to increase nucleotide diversity. The low genetic variability between both lo¬calities indicates the existence of a panmictic population that may have been split by factors such as habitat transformation, leading to isolated colonies. The preservation of this vulnerable species will depend on conservation efforts and studies that seek to supplement the analysis of genetic variability with other molecular markers, a continued monitoring of migratory processes, and inventorying of intermediate sites and localities with historical records.
The effects of Late Quaternary climate change have been examined for many temperate New World taxa, but the impact of Pleistocene glacial cycles on Neotropical taxa is less well understood, specifically with respect to changes in population demography. Here, we examine historical demographic trends for six species of milksnake with representatives in both the temperate and tropical Americas to determine if species share responses to climate change as a taxon or by area (i.e., temperate versus tropical environments). Using a multilocus dataset, we test for the demographic signature of population expansion and decline using non-genealogical summary statistics, as well as coalescent-based methods. In addition, we determine whether range sizes are correlated with effective population sizes for milksnakes. Results indicate that there are no identifiable trends with respect to demographic response based on location, and that species responded to changing climates independently, with tropical taxa showing greater instability. There is also no correlation between range size and effective population size, with the largest population size belonging to the species with the smallest geographic distribution. Our study highlights the importance of not generalizing the demographic histories of taxa by region and further illustrates that the New World tropics may not have been a stable refuge during the Pleistocene.
Pluralistic approaches to taxonomy facilitate a more complete appraisal of biodiversity, especially the diversification of cryptic species. Although species delimitation has traditionally been based primarily on morphological differences, the integration of new methods allows diverse lines of evidence to solve the problem. Robber frogs (Pristimantis) are exemplary, as many of the species show high morphological variation within populations, but few traits that are diagnostic of species. We used a combination of DNA sequences from three mitochondrial genes, morphometric data, and comparisons of ecological niche models (ENMs) to infer a phylogenetic hypothesis for the Pristimantis acuminatus complex. Molecular phylogenetic analyses revealed a close relationship between three new species—Pristimantis enigmaticus sp. nov., P. limoncochensis sp. nov. and P. omeviridis sp. nov.-originally confused with Pristimantis acuminatus. In combination with morphometric data and geographic distributions, several morphological characters such as degree of tympanum exposure, skin texture, ulnar/tarsal tubercles and sexual secondary characters (vocal slits and nuptial pads in males) were found to be useful for diagnosing species in the complex. Multivariate discriminant analyses provided a successful classification rate for 83–100% of specimens. Discriminant analysis of localities in environmental niche space showed a successful classification rate of 75–98%. Identity tests of ENMs rejected hypotheses of niche equivalency, although not strongly because the high values on niche overlap.
Changes in growth forms frequently accompany plant adaptive radiations, including paramo–a high-elevation treeless habitat type of the northern Andes. We tested whether diverse group of Senecio inhabiting montane forests and paramo represented such growth form changes. We also investigated the role of Andean geography and environment in structuring genetic variation of this group. We sampled 108 populations and 28 species of Senecio (focusing on species from former genera Lasiocephalus and Culcitium) and analyzed their genetic relationships and patterns of intraspecific variation using DNA fingerprinting (AFLPs) and nuclear DNA sequences (ITS). We partitioned genetic variation into environmental and geographical components. ITS-based phylogeny supported monophyly of a Lasiocephalus-Culcitium clade. A grade of herbaceous alpine Senecio species subtended the Lasiocephalus-Culcitium clade suggesting a change from the herbaceous to the woody growth form. Both ITS sequences and the AFLPs separated a group composed of the majority of paramo subshrubs from other group(s) comprising both forest and paramo species of various growth forms. These morphologically variable group(s) further split into clades encompassing both the paramo subshrubs and forest lianas, indicating independent switches among the growth forms and habitats. The finest AFLP genetic structure corresponded to morphologically delimited species except in two independent cases in which patterns of genetic variation instead reflected geography.
Novel species of fungi described in the present study include the following from Australia: Vermiculariopsiella eucalypti, Mulderomyces natalis (incl. Mulderomyces gen. nov.), Fusicladium paraamoenum, Neotrimmatostroma paraexcentricum, and Pseudophloeospora eucalyptorum on leaves of Eucalyptus spp., Anungitea grevilleae (on leaves of Grevillea sp.), Pyrenochaeta acaciae (on leaves of Acacia sp.), and Brunneocarpos banksiae (incl. Brunneocarpos gen. nov.) on cones of Banksia attenuata. Novel foliicolous taxa from South Africa include Neosulcatispora strelitziae (on Strelitzia nicolai), Colletotrichum ledebouriae (on Ledebouria floridunda), Cylindrosympodioides brabejum (incl. Cylindrosympodioides gen. nov.) on Brabejum stellatifolium, Sclerostagonospora ericae (on Erica sp.), Setophoma cyperi (on Cyperus sphaerocephala), and Phaeosphaeria breonadiae (on Breonadia microcephala). Novelties described from Robben Island (South Africa) include Wojnowiciella cissampeli and Diaporthe cissampeli (both on Cissampelos capensis), Phaeotheca salicorniae (on Salicornia meyeriana), Paracylindrocarpon aloicola (incl. Paracylindrocarpon gen. nov.) on Aloe sp., and Libertasomyces myopori (incl. Libertasomyces gen. nov.) on Myoporum serratum. Several novelties are recorded from La Réunion (France), namely Phaeosphaeriopsis agapanthi (on Agapanthus sp.), Roussoella solani (on Solanum mauritianum), Vermiculariopsiella acaciae (on Acacia heterophylla), Dothiorella acacicola (on Acacia mearnsii), Chalara clidemiae (on Clidemia hirta), Cytospora tibouchinae (on Tibouchina semidecandra), Diaporthe ocoteae (on Ocotea obtusata), Castanediella eucalypticola, Phaeophleospora eucalypticola and Fusicladium eucalypticola (on Eucalyptus robusta), Lareunionomyces syzygii (incl. Lareunionomyces gen. nov.) and Parawiesneriomyces syzygii (incl. Parawiesneriomyces gen. nov.) on leaves of Syzygium jambos.
The Aedes aegypti mosquito is an efficient vector for the transmission of Zika, chikungunya, and dengue viruses, causing major epidemics and a significant social and economic burden throughout the tropics and subtropics. The primary means of preventing these diseases is household-level mosquito control. However, relatively little is known about the economic burden of Ae. aegypti control in resource-limited communities. We surveyed residents from 40 households in a high-risk community at the urban periphery in the city of Machala, Ecuador, on dengue perceptions, vector control interventions, household expenditures, and factors influencing purchasing decisions. The results of this study show that households spend a monthly median of US$2.00, or 1.90% (range: 0.00%, 9.21%) of their family income on Ae. aegypti control interventions. Households reported employing, on average, five different mosquito control and dengue prevention interventions, including aerosols, liquid sprays, repellents, mosquito coils, and unimpregnated bed nets. We found that effectiveness and cost were the most important factors that influence people’s decisions to purchase a mosquito control product. Our findings will inform the development and deployment of new Ae. aegypti control interventions by the public health and private sectors, and add to prior studies that have focused on the economic burden of dengue-like illness.
Under the ongoing climate change, understanding the mechanisms structuring the spatial distribution of aquatic species in glacial stream networks is of critical importance to predict the response of aquatic biodiversity in the face of glacier melting. In this study, we propose to use metacommunity theory as a conceptual framework to better understand how river network structure influences the spatial organization of aquatic communities in glacierized catchments. At 51 stream sites in an Andean glacierized catchment (Ecuador), we sampled benthic macroinvertebrates, measured physico-chemical and food resource conditions, and calculated geographical, altitudinal and glaciality distances among all sites. Using partial redundancy analysis, we partitioned community variation to evaluate the relative strength of environmental conditions (e.g., glaciality, food resource) vs. spatial processes (e.g., overland, watercourse, and downstream directional dispersal) in organizing the aquatic metacommunity. Results revealed that both environmental and spatial variables significantly explained community variation among sites. Among all environmental variables, the glacial influence component best explained community variation. Overland spatial variables based on geographical and altitudinal distances significantly affected community variation. Watercourse spatial variables based on glaciality distances had a unique significant effect on community variation. Within alpine catchment, glacial meltwater affects macroinvertebrate metacommunity structure in many ways. Indeed, the harsh environmental conditions characterizing glacial influence not only constitute the primary environmental filter but also, limit water-borne macroinvertebrate dispersal. Therefore, glacier runoff acts as an aquatic dispersal barrier, isolating species in headwater streams, and preventing non-adapted species to colonize throughout the entire stream network.
Herein we present a geographical review to the genus Glyphonycteris in Ecuador. We confirm the first record for G. sylvestris for the country, which extends its range about 680 km southwest of the nearest previously known record. This first record belongs to an individual captured inSangay National Park, Morona Santiago province, eastern slopes of the Andes. We also review the records of G. daviesi deposited in scientific collections and mentioned in literature, report a new record from west of the Andes, and present a distribution map.
Currently, several concerns have been raised over metal contamination in the upper Amazon basin. Rivers that flow from the high Andes to the lowland Amazon are threatened by anthropogenic activities, which may, in turn, lead to increased metal concentrations in both water and sediments. In the present study, the impacts of multiple metal contamination sources in these ecosystems were identified. The degree of metal contamination was assessed in water and sediment and seed phytotoxicity analyses were carried out in samples taken from 14 sites located in upper Napo River tributaries, combining geochemical and ecotoxicological techniques. These tributaries were chosen based on their degree of anthropogenic contamination and proximity to known sources of relevant pollution, such as small-scale gold mining (MI), urban pollution (UP), fish farming (FF) and non-functional municipal landfill areas (LF). Our results suggest that anthropogenic activities are introducing metals to the aquatic ecosystem, as some metals were up to 500 times above the maximum permissible limits for the preservation of aquatic life established by Ecuadorian and North American guidelines. Sites located close to small-scale gold mining and sanitary landfills presented 100 to 1000 times higher concentrations than sites classified as "few threats". In water, Cd, Pb, Cu, Zn and Hg were mostly above the maximum permissible limits in the samples, while Cd in sediment reached concentrations 5-fold above the probable effect level (PEL). Phytotoxicity was associated through the diffuse contamination present in urban and landfill areas. Overall, metal concentrations and phytotoxicity assessments suggest anthropogenic effects to environmental contamination, even though natural sources cannot be disregarded. Anthropogenic effects in the eastern Andean Rivers need to be constantly monitored in order to build a complete picture on how pollution sources may affect this strategic Amazon basin area.
When asked to think about heat production in the natural world, our thoughts first turn to mammals, birds, and other warm- blooded animals. As mammals ourselves, we are often thankful for our ability to produce heat internally to raise body temperature above ambient temperature, through a process called endothermy. This phenomenon has fascinated naturalists and biologists for centuries (Heinrich 1999) and still has the capacity to surprise modern scientists, with new discoveries concerning the occurrence and evolution of endothermy in the animal world. Last year, for example, saw the discovery of the first entirely warmblooded fish (Wegner et al. 2015). The endothermy of this fish is a remarkable adaptation for swimming in cold waters. Endothermy also occurs in some plants. Since the first description of heat production in arum flowers by Lamarck (1778), many other flowering and seed bearing species have been shown to produce heat. The reasons for the evolution and ecological importance of endothermy in temperate and tropical plants are still a matter of debate, and any new field observations of plant endothermy constitute potentially interesting pieces in this eco-evolutionary jigsaw.
The accessibility of the lateral line system and its amenability to long-term in vivo imaging transformed the developing lateral line into a powerful model system to study fundamental morphogenetic events, such as guided migration, proliferation, cell shape changes, organ formation, organ deposition, cell specification and differentiation. In addition, the lateral line is not only amenable to live imaging during migration stages but also during postembryonic events such as sensory organ tissue homeostasis and regeneration. The robust regenerative capabilities of the mature, mechanosensory lateral line hair cells, which are homologous to inner ear hair cells and the ease with which they can be imaged, have brought zebrafish into the spotlight as a model to develop tools to treat human deafness. In this chapter, we describe protocols for long-term in vivo confocal imaging of the developing and regenerating lateral line.
En la actualidad, las enfermedades transmitidas por el mosquito Aedes aegypti, incluyendo las fiebres del dengue, chikungunya y Zika, se encuentran entre los principales problemas de salud en países tropicales. Si se considera que la biología de esta especie de insecto está influenciada en gran medida por las condiciones ambientales, podemos afirmar que los cambios previstos en el clima futuro del planeta tendrán un impacto considerable en el panorama epidemiológico de las enfermedades transmitidas A. aegypti. En el presente trabajo revisamos el estado del conocimiento actual sobre la influencia que factores ambientales pueden tener en la biología y fisiología de A. aegypti. Adicionalmente, discutimos cómo los cambios climáticos previstos para el futuro pueden afectar la capacidad vectorial de esta importante especie, con especial énfasis en el Ecuador y sus países vecinos.
The high tropical Andes host one of the richest alpine floras of the world, with exceptionally high levels of endemism and turnover rates. Yet, little is known about the patterns and processes that structure altitudinal and latitudinal variation in plant community diversity. Herein we present the first continental-scale comparative study of plant community diversity on summits of the tropical Andes. Data were obtained from 792 permanent vegetation plots (1 m ) within 50 summits, distributed along a 4200 km transect; summit elevations ranged between 3220 and 5498 m a.s.l. We analyzed the plant community data to assess: 1) differences in species abundance patterns in summits across the region, 2) the role of geographic distance in explaining floristic similarity and 3) the importance of altitudinal and latitudinal environmental gradients in explaining plant community composition and richness. On the basis of species abundance patterns, our summit communities were separated into two major groups: Puna and Paramo. Floristic similarity declined with increasing geographic distance between study-sites, the correlation being stronger in the more insular Paramo than in the Puna (corresponding to higher species turnover rates within the Paramo). Ordination analysis (CCA) showed that precipitation, maximum temperature and rock cover were the strongest predictors of community similarity across all summits. Generalized linear model (GLM) quasi-Poisson regression indicated that across all summits species richness increased with maximum air temperature and above-ground necromass and decreased on summits where scree was the dominant substrate.
In this work, a computational chemical study of Etoricoxib was carried out at the X/6311G(d,p) (where X=B3LYP, M06 and ωB97XD) level of theory, at the gas, aqueous and ethanol phases. Through the chemical reactivity descriptors derived from the DFT, it was possible to find that Etoricoxib structure exhibits a major chemical activity in water and ethanol phases in comparison to the gas phase, which suggests this drug would be more active in biological solvents like in blood, tissues and places where the ciclooxigenasa 2 (COX)-2 is found. In addition, a molecular docking analysis was conducted to study the interaction of Etoricoxib with the COX-2 active site. The results suggest that Etoricoxib interacts with 19 amino acid residues inside the COX-2 active site.
Reports of rust occurring on Berberis in Ecuador date from 1891, when Lagerheim collected and distributed specimens of two species that he labeled as “Sphenospora quitensis” and “Diorchidium berberidis”; subsequently, Arthur (1918) published descriptions of these specimens as Uropyxis quitensis and Sphenospora berberidis. Jackson (1931) proposed a new genus Edythea to accommodate three South American species of rust on Berberis: the two collected by Lagerheim (recombined as E. quitensis [the type species] and E. berberidis (Lagerh. ex Arthur) H.S. Jacks.) and a new species from Bolivia (E. tenella H.S. Jacks. & Holw.). Jackson (1931) depicts Edythea as having urediniospores and teliospores “borne in a very characteristic and presumably unusual manner” because of the lack of proper sori, as the mycelial threads emerge from the stomata without rupturing the leaf tissue to give rise to spores.
Dispersal is a key ecological process that influences plant community assembly. Therefore, understanding whether dispersal strategies are associated with climate is of utmost importance, particularly in areas greatly exposed to climate change. We examined alpine plant communities located in the mountain summits of the tropical Andes across a 4,000‐km latitudinal gradient. We investigated species dispersal strategies and tested their association with climatic conditions and their evolutionary history. We used dispersal‐related traits (dispersal mode and growth form) to characterize dispersal strategies for 486 species recorded on 49 mountain summits. Then we analysed the phylogenetic signal of traits and investigated the association between dispersal traits, phylogeny, climate and space using structural equation modelling and fourth‐corner analysis together with RLQ ordination. A median of 36% species in the communities was anemochorous (wind‐dispersed) and herbaceous. This dispersal strategy was followed by the barochory‐herb combination (herbaceous with unspecialized seeds, dispersed by gravity) with a median of 26.3% species in the communities. The latter strategy was common among species with distributions restricted to alpine environments. While trait states were phylogenetically conserved, they were significantly associated with a temperature gradient. Low minimum air temperatures, found at higher latitudes/elevations, were correlated with the prevalence of barochory and the herb growth form, traits that are common among Caryophyllales, Brassicaceae and Poaceae. Milder temperatures, found at lower latitudes/elevations, were associated with endozoochorous, shrub species mostly from the Ericaceae family.
Se describe e ilustra Magnolia mindoensis, una especie nueva de remanentes de bosque premontano en el Chocó biogeográfico colombiano-ecuatoriano. Esta especie se diferencia de Magnolia gilbertoi, una especie endémica de Colombia, por tener láminas foliares más grandes con venas laterales por lado menos numerosas, menor proporción de la longitud de la cicatriz estipular con respecto a la longitud del peciolo, menor número de brácteas, flores más grandes, pétalos abruptamente estrechos hacia la base vs. Gradualmente estrechos hacia la base y estambres más numerosos.
The recent scale-up in malaria control measures in Latin America has resulted in a significant decrease in the number of reported cases in several countries including Ecuador, where it presented a low malaria incidence in recent years (558 reported cases in 2015) with occasional outbreaks of both Plasmodium falciparum and Plasmodium vivax in the coastal and Amazonian regions. This success in malaria control in recent years has led Ecuador to transition its malaria policy from control to elimination. Results: This study evaluated the general knowledge, attitude and practices (KAP) about malaria, as well as its prevalence in four communities of an endemic area in northwest Ecuador. A total of 258 interviews to assess KAP in the community indicated that most people in the study area have a basic knowledge about the disease but did not use to contribute to its control. Six hundred and forty-eight blood samples were collected and analysed by thick blood smear and real-time PCR. In addition, the distribution of the infections was mapped in the study communities. Although, no parasites were found by microscopy, by PCR the total malaria prevalence was 7.5% (6.9% P. vivax and 0.6% P. falciparum), much higher than expected and comparable to that reported in endemic areas of neighbouring countries with higher malaria transmission. Serology using ELISA and immunofluorescence indicated 27% respondents for P. vivax and 22% respondents for P. falciparum.
Raoultella spp., a bacterium named after Didier Raoult, is a Gram-negative belonging to the Enterobacteriaceae family. There have been described 4 species: Raoultella planticola, Raoultella ornithinolytica, Raoultella terrigena, and Raoultella electrica, all species are inhabitants of soil and plants. Recently, R. planticola and R. ornithinolytica have been associated with human infections and resistance to different antibiotics including carbapenems. In this report, we describe an infection caused by blaOXA-48 producing R. ornithinolytica. A 64-year-old male patient was admitted into a 700-bed hospital in Quito, in order to restore intestinal transit after ileocecal resection. Two days after admission the patient presented sepsis characterized by hypotension, fever, and leukocytosis. The patient was directed to intensive care unit where he was treated with Ampicillin/sulbactam for 10 days, subsequent blood cultures were negative however Escherichia coli was recovered from tracheal aspirate.
Determining the extent of reproductive isolation in cryptic species with dynamic geographic ranges can yield important insights into the processes that generate and maintain genetic divergence in the absence of severe geographic barriers. We studied mating patterns, propensity to hybridize in nature and subsequent fertilization rates, as well as survival and development of hybrid F1 offspring for three nominal species of the Engystomops petersi species complex in YasunõÂ National Park, Ecuador. We found at least two species in four out of six locations sampled, and 14.3% of the wild pairs genotyped were mixed-species (heterospecific) crosses. We also found reduced fertilization rates in hybrid crosses between E. petersi females and E. ªmagnusº males, and between E. ªmagnusº females and E. ªselvaº males but not in the reciprocal crosses, suggesting asymmetric reproductive isolation for these species. Larval development times decreased in F1 hybrid crosses compared to same species (conspecific) crosses, but we did not find significant reduction in larval survival or early metamorph survival. Our results show evidence of post-mating isolation for at least two hybrid crosses of the cryptic species we studied. The general decrease in fertilization rates in heterospecific crosses suggests that sexual selection and reinforcement might have not only contributed to the pattern of call variation and behavioral isolation we see between species today, but they may also contribute to further signal divergence and behavioral evolution, especially in locations where hybridization is common and fertilization success is diminished.
En este estudio, se presenta la modelación computacional de la interacción del paracetamol y su metabolito activo, el 4-aminofenol, con las enzimas Ciclooxigenasa 1 y Ciclooxigenasa 2. El objetivo fue utilizar métodos computacionales para explicar, a nivel molecular, la baja actividad antinflamatoria del paracetamol mediante su interacción con las enzimas Ciclooxigenasa 1 y 2. Se utilizaron métodos mecánico cuánticos para la optimización de los ligandos y acoplamiento molecular para modelar la interacción de estos ligandos con las enzimas y sus sitios activos. Los resultados obtenidos muestran que las conformaciones con más afinidad para paracetamol y 4-aminofenol no se encuentran en el sitio activo de la Ciclooxigenasa 1. Comparaciones con el ácido araquidónico muestran que las energías de enlace son alrededor de 1 kcal/mol mayores, lo cual indica una inhibición leve. Para el caso de la Ciclooxigenasa 2, los resultados obtenidos son similares, lo cual sugiere que el mecanismo de acción principal del paracetamol o su metabolito primario no se da por inhibición de las Ciclooxigenasas. Este resultado concuerda con las diferencias en la acción farmacológica y efectos secundarios que tiene el paracetamol con respecto a moléculas del mismo grupo como el ibuprofeno.
Chagas disease is caused by the protozoan Trypanosoma cruzi Panstrongylus chinai (Del Ponte) is highly domiciliated in the Peruvian and Ecuadorian Andes and has been found naturally infected with T. cruzi The objective of this study was to describe the life cycle, feeding, and defecation patterns of P. chinai in the Loja province within southern Ecuador. To characterize its life cycle, a cohort of 70 individuals was followed from egg to adult. At each stage of development, prefeeding time, feeding time, weight of ingested meal, proportional weight increase, and the time to the first defecation were recorded. Panstrongylus chinai completed its development in 371.4 ± 22.3 d, (95% CI 355.4-387.4), which means that it is likely a univoltine species. Prefeeding time, feeding time, and weight of ingested meal increased as individuals developed through nymphal stages. Moreover, time to first defecation was shortest in the early nymphal stages, suggesting higher vector potential in the early developmental stages. Data obtained in this study represent an important advance in our knowledge of the biology of P. chinai, which should be considered as a secondary Chagas disease vector species in the Andean valleys of Loja (Ecuador) and in the north of Peru, and included in entomological surveillance programs.
Reptiles are a highly diverse class that consists of snakes, geckos, iguanid lizards, and chameleons among others. Given their unique phylogenetic position in relation to both birds and mammals, reptiles are interesting animal models with which to decipher the evolution of vertebrate photopigments (opsin protein plus a light-sensitive retinal chromophore) and their contribution to vision. Reptiles possess different types of retinae that are defined primarily by variations in photoreceptor morphology, which range from pure-cone to rod-dominated retinae with many species possessing duplex (rods and cones) retinae. In most cases, the type of retina is thought to reflect both the lifestyle and the behavior of the animal, which can vary between diurnal, nocturnal, or crepuscular behavioral activities. Reptiles, and in particular geckos and snakes, have been used as prime examples for the “transmutation” hypothesis proposed by Walls in the 1930s-1940s, which postulates that some reptilian species have migrated from diurnally to nocturnality, before subsequently returning to diurnal activities once again. This theory further states that these behavioral changes are reflected in subsequent changes in photoreceptor morphology and function from cones to rods, with a return to cone-like photoreceptors once again. Modern sequencing techniques have further investigated the “transmutation” hypothesis by using molecular biology to study the phototransduction cascades of rod- and cone-like photoreceptors in the reptilian retina. This review will discuss what is currently known about the evolution of opsin-based photopigments in reptiles, relating habitat to photoreceptor morphology, as well as opsin and phototransduction cascade gene expression.
We describe a small frog of the genus Pristimantis inhabiting bromeliads (snout-vent length 20.3‑23.3 mm in females, 16.1‑17.4 mm in males), from a remote sandstone plateau of the Cordillera del Condor, in southeastern Ecuador, with an altitudinal range of 2,045‑2,860 m. A phylogeny based on sequences of DNA (mitochondrial and nuclear genes) supports inclusion in the P. orestes group and suggests an undescribed Pristimantis from the southern slope of eastern Ecuador as the closest taxon. The new species differs from its congeners in Ecuador by having predominantly black dorsal and ventral coloration; comprehensive and robust palmar surface with stubby fingers; presence of a deep and wide groove from the anterior base of finger I to the rear base of the palmar tubercle; subarticular divided tubers, enlarged supernumerary small granules and tubercles. All individuals were found in terrestrial bromeliads. The calls are short, frequency modulated, comprising of a note 5‑15 ms in duration. Insects represented 80% of the diet of the new species.
It is well known that modern analysis directly or indirectly involve the applications of convexity (see ), due to its applications and significant importance. Several generalizations have been introduced in recent years and extensions of the classical notion of convex function and in the theory of inequalities are produced important contributions in this regard (see [16,3,11,13,14]). In , Noor introduced a new class of convex set and convex function with respect to an arbitrary function; which are called relative convex set and relative convex function respectively, and in  established some Hadamard’s type inequality for relative convex functions. Let K be a nonempty closed set in a real Hilbert spaces H.
The tropical alpine flora in the northern Andes has caught the attention of evolutionary biologists and conservationists because of the extent of its diversity and its vulnerability. Although population genetics studies are essential to understand how diversity arises and how it can be maintained, plant populations occurring above 4100 m a.s.l. in the so-called super-páramo have rarely been studied at the molecular level. Here, we use 11 microsatellite DNA markers to examine genetic structure in populations of Lupinus alopecuroides, a long-lived semelparous giant rosette known from only 10 geographically isolated populations. Each population is located on a different mountain top, of which three are in Colombia and seven in Ecuador. We analysed 220 individuals from all the ten known populations. We find low genetic variation in all but one of the populations. Four populations are completely monomorphic, and another five show only one polymorphic locus each. On the other hand, we find extremely high genetic differentiation between populations. We discuss the mechanisms that might cause this pattern, and we suggest that it is related to founder effects, lack of gene flow, and autogamy. The genetic relationships among the populations, and the lack of correlation between the genetic and geographic distances also point to the importance of founder effects and colonization history in driving differentiation among the populations.
We describe here two new species: Magnolia chiguila and M. mashpi and a new subsection, Magnolia subsect. Chocotalauma, sect. Talauma (Magnoliaceae). Magnolia chiguila is morphologically similar to M. calimaensis, but differs from the latter in having larger and broadly elliptic leaves with larger number of lateral veins and larger flowers with more numerous stamens and carpels. Magnolia mashpi is morphologically similar to M. striatifolia, but differs from the latter in having wider and broadly elliptic to obovate leaves with strongly arched lateral veins that are bullate and abaxially pubescent, more numerous stamens, carpels with a prominent apicule, longer sepals, larger outer and inner petals and glabrous peduncular internodes. The new species are found in the Pacific lowlands of western Ecuador, and all species of the new subsection are restricted to the Chocó biogeographic region of western Colombia and Ecuador. A key to the species of Magnolia subsects. Chocotalauma and Dugandiodendron is provided.
El turismo es considerado como una de las estrategias clave que promueve tanto la conservación ambiental como el desarrollo socio-económico de comunidades locales en áreas protegidas. Las reservas de biosfera de la UNESCO son áreas protegidas de extraordinario valor natural y cultural, concebidas como sitios de reconciliación entre conservación y desarrollo. El objetivo fundamental de la presente investigación fue evaluar los elementos más relevantes de la actual gestión del turismo y su contribución a la conservación de la biodiversidad y el desarrollo en dos reservas de biosfera ecuatorianas: Galápagos y Sumaco (Amazonía ecuatoriana). Además, se evaluó la sustentabilidad del turismo en ambas reservas de biosfera. La recolección de datos en los dos casos de estudio se llevó a cabo combinando métodos cuantitativos y cualitativos. Encuestas fueron aplicadas a residentes en ambas reservas de biosfera con la finalidad de establecer sus características socio-demográficas, las principales actividades económicas a las que se dedican y su relación con el turismo además de su nivel de conocimiento sobre reservas de biosferas.
Vegetables are one of the most important components in the human diet, but despite their multiple nutritional components, studies have demonstrated the presence of trace metals in their edible parts. In Ecuador, two of the most consumed crops are tomato (Solanum lycopersicum) and lettuce (Lactuca sativa). The importance of these two crops in the Ecuadorian diet, especially in large and touristic locations like the Metropolitan District of Quito, implies food safety-related concerns for locals and visitors. However, no previous studies have quantified the cadmium and lead levels in these two vegetables using samples from Quito markets. Thus, the aim of this study was to determine the cadmium and lead content in both tomato and lettuce products from main nonorganic and organic markets in Quito using a graphite furnace atomic absorption spectrophotometer. The results showed that the cadmium levels were lower than 0.058 in tomatoes and 0.034 mg/kg in lettuce, which are under the respective threshold values (0.100 and 0.200 mg/kg). Regarding lead, levels lower than 0.066 mg/kg were detected in lettuce, which did not exceed the CXS 193-1995 threshold value, while levels in tomatoes were near or exceeded the threshold value (0.100 mg/kg) from four markets (0.209, 0.162, 0.110, 0.099 mg/kg), suggesting a possible risk from tomato consumption. In addition, most vegetables marketed as organic had higher metal content than those coming from nonorganic markets. Based on these results, local health and commercial control authorities should monitor contaminants in food products sold in Quito and other places in Ecuador to ensure their safety.
Riama is the most speciose genus of the Neotropical lizard family Gymnophthalmidae. Its more than 30 montane species occur throughout the northern Andes, the Cordillera de la Costa (CC) in Venezuela, and Trinidad. We present the most comprehensive phylogenetic analysis of Riama to date based on a total evidence (TE) approach and direct optimization of molecular and morphological evidence. Analyses use DNA sequences from four loci and 35 phenotypic characters. The dataset consists of 55 ingroup terminals representing 25 of the 30 currently recognized species of Riama plus five undescribed taxa, including an endemic species from the Sierra Nevada de Santa Marta (SNSM) in Colombia, and 66 outgroup terminals of 47 species. Analysis results in a well-supported hypothesis in which Riama is polyphyletic, with its species falling into three clades. The Tepuian Anadia mcdiarmidi nests within one clade of Riama, and the recently resurrected Pantodactylus nests within Cercosaura. Accordingly, we propose a monophyletic taxonomy that reflects historical relationships. Analysis of character evolution indicates that the presence/absence of prefrontals—a cornerstone of the early genus-level taxonomy of cercosaurines—is optimally explained as having been plesiomorphically present in the most recent common ancestor of Cercosaurinae and lost in that of the immediately less inclusive clade. Multiple independent reversals to present and subsequent returns to absent occur within this clade.
Effective control of Chagas disease vector populations requires a good understanding of the epidemiological components, including a reliable analysis of the genetic structure of vector populations. Rhodnius ecuadoriensis is the most widespread vector of Chagas disease in Ecuador, occupying domestic, peridomestic and sylvatic habitats. It iswidely distributed in the central coast and southern highlands regions of Ecuador, two very different regions in terms of bio-geographical characteristics. To evaluate the genetic relationshipamong R. ecuadoriensis populations in these two regions, we analyzed genetic variability at two microsatellite loci for 326 specimens (n = 122 in Manabí and n=204 in Loja) and the mitochondrial cytochrome b gene (Cyt b) sequences for 174 individuals collected in the two provinces (n= 73 and = 101 in Manabí and Loja respectively). The individual samples were grouped in populations according to their community of origin. A fewpopulations presented positive FIS, possible due toWahlund effect. Significant pairwise differentiation was detected between populations within each province for both genetic markers, and the isolation by distance model was significant for these populations. Microsatellite markers showed significant genetic differentiation between the populations of the two provinces.
Substantial heterogeneity exists in the dispersal, distribution and transmission of parasitic species. Understanding and predicting how such features are governed by the ecological variation of landscape they inhabit is the central goal of spatial epidemiology. Genetic data can further inform functional connectivity among parasite, host and vector populations in a landscape. Gene flow correlates with the spread of epidemiologically relevant phenotypes among parasite and vector populations (e.g., virulence, drug and pesticide resistance), as well as invasion and re-invasion risk where parasite transmission is absent due to current or past intervention measures. However, the formal integration of spatial and genetic data (‘landscape genetics’) is scarcely ever applied to parasites. Here, we discuss the specific challenges and practical prospects for the use of landscape genetics and genomics to understand the biology and control of parasitic disease and present a practical framework for doing so.
We provide a synopsis to the family Dennstaedtiaceae in Bolivia, including 28 species (30 taxa) in 7 genera. Two endemic species of Hypolepis, H. periculosa and H. woodii, and a widespread subspecies of Pteridium esculentum, subsp. gryphus, are described as new.
Two new species of Myrtaceae from Yasuní National Park in Ecuadorian Amazon, Myrcia gigantifolia and Plinia valenciana, are described and illustrated. Myrcia gigantifolia grows in Varzea forest along Tiputini river, while Plinia valenciana grows in lowland forest.
Santa Rosa Island community members derive their income and livelihoods from bio-aquatic resources, principally bivalves of the genus Anadara, both for subsistence use and commercial purposes. Bivalve mollusks have a sedentary lifestyle and feed by filtering water, meaning they absorb all surrounding substances, including harmful elements like toxic metals. This study aimed to analyze different-sized samples of Anadara tuberculosa and Anadara similis, sediment, and Rhizophora mangle leaves to determine their total amount of cadmium, lead, and chromium as a first approach to the evaluation of the health risk related to the consumption of bivalves. For both species from four sampling sites, the results revealed metal concentrations in the bivalves between 0.211 and 0.948 mg kg–1, 0.038, and 0.730 mg kg–1, and 0.067 and 0.923 mg⋅kg–1 for Cd, Cr, and Pb, respectively. The calculated potential risk (>1) for cadmium, considering all body weights, showed a high health risk for consumers. In the case of lead, the results showed a high health risk in children. There was no risk found for chromium. For sediments, the mean values were 2.14, 29.99, and 12.37 mg⋅kg–1 and for the Rhizophora mangle leaves were 2.23, 4.22, and 3.35 mg⋅kg–1 for Cd, Cr, and Pb, respectively. These results did not show a relation with the metal content in bivalves.
Assembly of ecological communities is important for the conservation of ecosystems, predicting perturbation impacts, and understanding the origin and loss of biodiversity. We tested how amphibian communities are assembled by neutral and niche‐based mechanisms, such as habitat filtering. Species richness, β‐diversities, and reproductive traits of amphibians were evaluated at local scale in seven habitats at different elevation and disturbance levels in Wisui Biological Station, Morona‐Santiago, Ecuador, on the foothills of the Cordillera del Kutukú; and at regional scale using 109 localities across evergreen forests of Amazonia and its Andean slopes (0–3,900 m a.s.l.). At local scale, species composition showed strong differences among habitats, explained mainly by turnover. Reproductive modes occurred differently across habitats (e.g., prevalence of direct developers at high elevation, where breeding in ground level water disappears). At regional scale, elevation was the most important factor explaining the changes in species richness, reproductive trait occurrences, and biotic dissimilarities. Species number in all groups decreased with elevation except for those with lotic tadpoles and terrestrial reproduction stages. Seasonality, annual precipitation, and relative humidity partially explained the occurrence of some reproductive traits. Biotic dissimilarities were also mostly caused by turnover rather than nestedness and were particularly high in montane and foothill sites. Within lowlands, geographic distance explained more variability than elevation.
Problems associated with delimiting species are particularly pronounced in taxa with high species-level diversity, as occurs in Pristi ti frogs. Herein, we resurrect Pristimantis brevicrus, nov. comb., from the synonymy of P. altamazonicus, a widespread species in the upper Amazon Basin, based on morphological, acoustic and genetic evidence. Both species are sympatric along the Upper Amazon Basin of Ecuador and northern Peru, up to 1450 m. Phylogenetic analyses reveals that P. altamazonicus and P. brevicrus are sister taxa in a well-supported clade with P. diadematus and two unconfirmed candidate species. Pristimantis altamazonicus is distinguished from P. brevicrus by having a differentiated tympanic annulus, a smooth dorsum with scattered small tubercles towards the flanks, weakly areolate skin on the venter, red to bright orange groin with black mottling, on hidden surfaces of thighs (bluish-white to yellowish-white in P. brevicrus) of living specimens. The recognition of P. brevicrus and two unconfirmed candidate species suggest that the diversity of these frogs is inadequately understood, highlighting the need for more integrative taxonomic reviews of Amazonian amphibians.
The question whether taxonomic descriptions naming new animal species without type specimen(s) deposited in collections should be accepted for publication by scientific journals and allowed by the Code has already been discussed in Zootaxa (Dubois & Nemésio 2007; Donegan 2008, 2009; Nemésio 2009a–b; Dubois 2009; Gentile & Snell 2009; Minelli 2009; Cianferoni & Bartolozzi 2016; Amorim et al. 2016). This question was again raised in a letter supported by 35 signatories published in the journal Nature (Pape et al. 2016) on 15 September 2016. On 25 September 2016, the following rebuttal (strictly limited to 300 words as per the editorial rules of Nature) was submitted to Nature, which on 18 October 2016 refused to publish it. As we think this problem is a very important one for zoological taxonomy, this text is published here exactly as submitted to Nature, followed by the list of the 493 taxonomists and collection-based researchers who signed it in the short time span from 20 September to 6 October 2016.
Foam nests have evolved independently in several amphibian groups as an adaptive response to prevent predation and desiccation in dry environments. Nests are normally laid on ponds, or in underground galleries, humid forest leaf litter or terrestrial bromeliads. They are built when males or females beat a foam precursor associated with the egg masses extruded by the female. The spawning process requires the synchronic actions of the mating pair to obtain a hemispheric nest that protects the offspring. Herein, we describe the spawning behaviour of Engystomops pustulatus based on videos from 13 nesting couples from the lowlands of western Ecuador. Three variables were measured as indicators of male effort: duration of mixing events, duration of resting periods, and number of kicks per mixing event. We consider that not only male physical effort but also female behaviour influences nest structure. We suggest that nest building requires prolonged and intense physical activity by the male as well as the female’s steady position during spawning and female’s oviposition site selection. Nest building has two phases. In the first phase, the duration of resting periods, the duration of mixing events, and the number of kicks increase and are highly variable. During the second phase the three variables stabilise until the end.
Nearly 50% of the diversity of the speciose Neotropical lizard clade Gymnophthalmidae is nested within the subclade Cercosaurinae. The taxonomy of ercosaurinae lizards has been historically confusing because many diagnostic characters of those clades traditionally ranked as genera do not represent true diagnostic apomorphies. Even though molecular phylogenies of several ‘genera’ have been presented in the last few years, some of them remain poorly sampled (e.g., Anadia, Echinosaura, Potamites, Riama). In this paper we present a more comprehensive phylogeny of Cercosaurinae lizards with emphasis on Andean taxa from Ecuador and Peru, as well as a time-calibrated phylogeny with reconstruction of ancestral areas. Our analysis includes 52% of all recognized species of Cercosaurinae (67 species) and 1914 characters including three mitochondrial and one nuclear gene. We find that Anadia, Echinosaura, Euspondylus, Potamites, Proctoporus, and Riama are not monophyletic: the Tepuian Anadia mcdiarmidi is not sister to Andean species of Anadia; Echinosaura sulcarostrum is not included in the same clade formed by other species of Echinosaura and their more recent common ancestor; Teuchocercus is nested within Echinosaura; species of Euspondylus included in this study are nested within Proctoporus; Riama laudahnae is included in Proctoporus; and Potamites is paraphyletic and split in two separate clades, one of which we name Gelanesaurus, also a new genus-group name. Within Potamites, P. ecpleopus is paraphyletic, and P. strangulatus strangulatus and P. strangulatus trachodus are recognized as two distinct species.
Genetic data in studies of systematics of Amazonian amphibians frequently reveal that purportedly widespread single species in reality comprise species complexes. This means that real species richness may be significantly higher than current estimates. Here we combine genetic, morphological, and bioacoustic data to assess the phylogenetic relationships and species boundaries of two Amazonian species of the Dendropsophus leucophyllatus species group: D. leucophyllatus and D. triangulum. Our results uncovered the existence of five confirmed and four unconfirmed candidate species. Among the confirmed candidate species, three have available names: Dendropsophus leucophyllatus, Dendropsophus triangulum, and Dendropsophus reticulatus, this last being removed from the synonymy of D. triangulum. A neotype of D. leucophyllatus is designated. We describe the remaining two confirmed candidate species, one from Bolivia and another from Peru. All confirmed candidate species are morphologically distinct and have much smaller geographic ranges than those previously reported for D. leucophyllatus and D. triangulum sensu lato. Dendropsophus leucophyllatus sensu stricto occurs in the Guianan region. Dendropsophus reticulatus comb. nov. corresponds to populations in the Amazon basin of Brazil, Ecuador, and Peru previously referred to as D. triangulum. Dendropsophus triangulum sensu stricto is the most widely distributed species; it occurs in Amazonian Ecuador, Peru and Brazil, reaching the state of Pará. We provide accounts for all described species including an assessment of their conservation status
In this study, a computational DFT study was performed to propose a new acid catalyzed mechanism to produce 5HMF from d-Fructose and d-Tagatose. The reactivity and selectivity towards 5HMF formation were analyzed, and the results revealed both saccharides present higher selectivity towards 5HMF with the first dehydration occurring on oxygen 2. Fructose seems to be more reactive than tagatose, although the dehydration process of the different hydroxyl groups on tagatose produces more unstable structures, which can undergo several side reactions. The new mechanism is proposed eliminating the tautomerization step and lowering the activation free energy of the second dehydration step in 21 kcal/mol.
Seasonally dry tropical forests are distributed across Latin America and the Caribbean and are highly threatened, with less than 10% of their original extent remaining in many countries. Using 835 inventories covering 4660 species of woody plants, we show marked floristic turnover among inventories and regions, which may be higher than in other neotropical biomes, such as savanna. Such high floristic turnover indicates that numerous conservation areas across many countries will be needed to protect the full diversity of tropical dry forests. Our results provide a scientific framework within which national decision-makers can contextualize the floristic significance of their dry forest at a regional and continental scale. Neotropical seasonally dry forest (dry forest) is a biome with a wide and fragmented distribution, found from Mexico to Argentina and throughout the Caribbean (1, 2) (Fig. 1). It is one of the most threatened tropical forests in the world (3), with less than 10% of its original extent remaining in many countries (4).
Begonia albomaculata as circumscribed in the Flora of Ecuador and related publications is shown to be a misapplied name and represents an undescribed species. This is described as Begonia botryoides Moonlight & Tebbitt sp. nov., and is recorded from the Pichincha, Santo Domingo de los Tsáchilas, Napo, Cotopaxi, Azuay and El Oro provinces in Ecuador, and the Antioquia and Chocó departments of Colombia. The taxonomic study of this species prompted a re-evaluation of related species. It was subsequently found that the Central American material previously included in Begonia tiliifolia C.DC. is distinct from the type and other South American material of this species and represents an undescribed species. This is described as Begonia boreoharlingii Tebbitt & Moonlight sp. nov., and is recorded from the Limón province in Costa Rica, and the Bocas del Toro and Coclé provinces in Panama. Four species, Begonia tiliifolia C.DC., Begonia harlingii L.B.Sm. & Wassh., B. botryoides and B. boreoharlingii, are placed in the informally named Begonia tiliifolia group. A key, descriptions, illustrations and distribution maps are provided for the members of the Begonia tiliifolia group, and its sectional classification is discussed.
We re-examined the biogeography of the leaf-toed geckos (Phyllodactylus) endemic to the Galápagos Islands by analyzing for the first time samples of P. gilberti, a species endemic to Wolf island, in a phylogenetic framework. Our aim was to test the three-colonizations scenario previously proposed for these lizards and estimate the age of each colonization event. To achieve this we estimated simultaneously a species tree and divergence times with Bayesian methods. Our results supported the three-colonizations scenario. Similar to a previous hypothesis, the species tree obtained here showed that most species of Phyllodactylus are nested in a single clade with an age between 5.49 and 13.8 Ma, whereas a second independent colonization corresponding to P. darwini from San Cristóbal island occurred 3.03 Ma ago. The species from Wolf island, P. gilberti, stems from a more recent colonization event (0.69 Ma). Thus, present diversity of Galápagos leaf-toed geckos stems from three independent, asynchronous colonization events. As with other Galápagos organisms, the Pacific coast of South America seems to be the source for the founders of P. gilberti.
Introduction. The Cordillera del Cóndor on the border between Ecuador and Peru stands out because of its rich biodiversity and high endemism. Here we describe a new dendroid species of the thalloid liverwort genus Riccardia, R. verticillata Gradst. & Reeb, from El Quimi Biological Reserve in the Cóndor region of Ecuador. Methods. The plants are described using anatomical and morphological methods. For the anatomical study, plants were treated with bleach (20%) and stained with methylene blue, enhancing observation of the thallus structure. Key results. The plants consist of a stout, erect axis with a subepidermis and regularly spaced, horizontally spreading and flattened, densely 4–6 pinnate fronds, which are arranged in whorls. The axis and primary branches are wingless; the younger branches are broadly winged. An erect axis with a subepidermis and winged branches are also seen in the neotropical R. aberrans, R. ciliolata, R. fucoidea, R. gradsteinii, R. pallida, R. poeppigiana and R. wallisii, but these species are less densely pinnate and the branches are not arranged in horizontally spreading, flattened whorls, and are mostly fully winged. In its verticillate habit, the new species is similar only to members of R. subg. Arconeura, including R. prehensilis from Tierra del Fuego and R. eriocaula from Australasia. A key to dendroid neotropical species of Riccardia is provided. Conclusion. Riccardia verticillata stands out among neotropical Riccardia species by its markedly whorled habit. This discovery adds a further endemic taxon to the Cóndor region.
Rapid radiation coupled with low genetic divergence often hinders species delimitation and phylogeny estimation even if putative species are phenotypically distinct. Some aposematic species, such as poison frogs (Dendrobatidae), have high levels of intraspecific color polymorphism, which can lead to overestimation of species when phenotypic divergence primarily guides species delimitation. We explored this possibility in the youngest origin of aposematism (3–7 MYA) in poison frogs, Epipedobates, by comparing genetic divergence with color and acoustic divergence. We found low genetic divergence (2.6% in the 16S gene) despite substantial differences in color and acoustic signals. While chemical defense is inferred to have evolved in the ancestor of Epipedobates, aposematic coloration evolved at least twice or was lost once in Epipedobates, suggesting that it is evolutionarily labile. We inferred at least one event of introgression between two cryptically colored species with adjacent ranges (E. boulengeri and E. machalilla). We also find evidence for peripheral isolation resulting in phenotypic divergence and potential speciation of the aposematic E. tricolor from the non-aposematic E. machalilla. However, we were unable to estimate a well-supported species tree or delimit species using multispecies coalescent models. We attribute this failure to factors associated with recent speciation including mitochondrial introgression, incomplete lineage sorting, and too few informative molecular characters. We suggest that species delimitation within young aposematic lineages such as Epipedobates will require genome-level molecular studies.
Brunellia ephemeropetala, a new species discovered in Llanganates National Park, Ecuador is described and illustrated. This species belongs to a group of species that have unifoliate leaves, large fruits and navicular endocarp, in which B. ephemeropetala is distinguished by large and thin stipules, leafy inflorescence and the presence of a petal whorl. For the first time, the presence of petals is recorded in Brunellia, a genus previously considered apetalous.
In this work, a new hydrogen peroxide (H2O2) electrochemical sensor was fabricated. Prussian blue (PB) was electrodeposited on a glassy carbon (GC) electrode modified with zirconia doped functionalized carbon nanotubes (ZrO2-fCNTs), (PB/ZrO2-fCNTs/GC). The morphology and structure of the nanostructured system were characterized by scanning and transmission electron microscopy (TEM), atomic force microscopy (AFM), specific surface area, X-ray diffraction (XRD), thermogravimetric analysis (TGA), Raman and Fourier transform infrared (FTIR) spectroscopy. The electrochemical properties were studied by cyclic voltammetry (CV) and chronoamperometry (CA). Zirconia nanocrystallites (6.6 ± 1.8 nm) with cubic crystal structure were directly synthesized on the fCNTs walls, obtaining a well dispersed distribution with a high surface area. The experimental results indicate that the ZrO2-fCNTs nanostructured system exhibits good electrochemical properties and could be tunable by enhancing the modification conditions and method of synthesis. The fabricated sensor could be used to efficiently detect H2O2, presenting a good linear relationship between the H2O2 concentration and the peak current, with quantification limit (LQ) of the 10.91 μmol·L−1 and detection limit (LD) of 3.5913 μmol·L−1
Ecuador has some of the greatest biodiversity in the world, sheltering global biodiversity hotspots in lowland and mountain regions. Climate change will likely have a major effect on these regions, but the consequences for faunal diversity and conservation remain unclear. To address this issue, we used an ensemble of eight species distribution models to predict future shifts and identify areas of high changes in species richness and species turnover for 201 mammals. We projected the distributions using two different climate change scenarios at the 2050 horizon and contrasted two extreme dispersal scenarios (no dispersal vs. full dispersal). Our results showed extended distributional shifts all over the country. For most groups, our results predicted that the current diversity of mammals in Ecuador would decrease significantly under all climate change scenarios and dispersal assumptions. The Northern Andes and the Amazonian region would remain diversity hotspots but with a significant decrease in the number of species.
Se reporta el estudio del contenido de Pb(II) en seis marcas de cervezas artesanales de la ciudad de Quito-Ecuador, utilizando Voltametría de Redisolución Anódica con Pulso Diferencial (DPASV, por sus siglas en inglés), diamante dopado con boro (BDD, por sus siglas en inglés) como electrodo de trabajo y buffer de acetato como solución electrolítica. La caracterización del BDD se llevó a cabo mediante Microscopía Electrónica de Barrido (SEM, por sus siglas en inglés) y Voltamperometría Cíclica (VC). Los resultados por SEM mostraron que la superficie de electrodos de BDD es rugosa y granular, la cual presentó una baja corriente capacitiva y una respuesta electroquímica quasi-reversible frente al par redox Ferri/Ferrocianuro de potasio. El método se optimizó en un rango lineal entre 0,3-1,3 mg L-1, se obtuvo repetibilidad con un RSD del 4,56 %, reproducibilidad del 9,19 % y límite de detección de 0,020 mg L-1. Las cervezas analizadas fueron etiquetadas como A, B, C, D, E y F, preservando así la identidad de las marcas que participaron en el estudio. Las muestras de cerveza B, C, D y E cumplen con la normativa NTE INEN 2262 para Pb(II) con una concentración por debajo de su límite máximo permitido de 0,1 mg L-1; mientras las muestras A y F exceden del límite máximo permisible.
Egg morphometrics in the Triatominae has proved to be informative for distinguishing tribes or genera, and has been based generally on traditional morphometrics. However, more resolution is required, allowing species or even population recognition, because the presence of eggs in the domicile could be related to the species ability to colonize human dwellings, suggesting its importance as a vector.
The pollen record from Lagunas de Mojanda, located at 3748 m a.s.l. (northern Ecuadorian Andes) reflects the vegetation and climate dynamics for the last ca 3400 cal yr BP. Paramo vegetation has been the main vegetation type since the beginning of the record. At Lagunas de Mojanda, from the last ca 3400 to 2200 cal yr BP, grass paramo was well represented mainly by Poaceae (40%) and the occurrence of Valeriana (5%), while montane forest taxa were poorly represented and sub paramo taxa were rare. The vegetation composition suggests cool and humid conditions. Between ca 2200 and ca 1300 cal yr BP, montane rainforest and sub paramo taxa had a higher presence but paramo taxa remained the main vegetation type in the study area, suggesting cool climatic conditions. From ca 1300 to ca 500 cal yr BP, paramo vegetation remained stable, with higher presence of Phlegmariurus and Isoetes, suggesting cool and humid conditions. The last ca 500 cal yr BP generally show lower frequency of montane rainforest and sub paramo taxa. Páramo vegetation reached the highest share, with the presence of Poaceae, Plantago and Ranunculus suggesting a trend of peat bog drying. Fires were present during the whole record, perhaps human-caused, but the study area does not show great disturbance except from ca 1300 to 500 cal yr BP, a period of an evident higher influx of charcoal particles coincidentally with nearby ancient human occupation.
Chagas disease (CD) is caused by Trypanosoma cruzi and transmitted by the feces of Triatomine insects. The absence of treatments and effective vaccines makes this disease not only a medical problem, but also an educational, social and psychological problem. Education appears as an important axis of research for the prevention of this disease. For this reason, we proposed the design and develop of a videogame for children, as an educational tool to raise awareness about CD in vulnerable areas of Ecuador. The videogame design was focused on the risk factors of the CD, and under the guidelines of a Game Document Design, and it’s development was based on the agile Scrum methodology, that was structured in sprints; and the Unity videogame engine. Nielsen heuristics was applied to perform usability tests on children from 7 to 11 years old. Finally, the video game is ready to be used and broadcast the message for CD prevention in the rural communities of Manabí, Ecuador.
We studied the thermal physiology of the Andean lizard Stenocercus guentheri in order to evaluate the possible effects of global warming on this species. We determined the preferred body temperature (Tpref), critical thermals (CTmin, CTmax), and hours of restriction and activity. Tpref was 32.14±1.83°C; CTmin was 8.31°C in adults and 9.14°C in juveniles, whereas CTmax was 43.28°C in adults and 41.68°C in juveniles. To assess extinction risk, we used the model created by Sinervo et al. (2010) and predicted that 16.7% of populations will have a high risk of extinction by 2020, with an increase to 26.7% by 2050. These results suggest that this species, despite being able to maintain its Tpref through behavioral thermoregulation and habitat selection, could be physiologically sensitive to climate warming; thus, the potential for local adaptation may be limited under a warmer climate. Further studies focusing on the ability of S. guentheri to evolve higher Tpref and thermal tolerances are needed to understand the ability of this species to respond to climate change.
Genetic exchange enables parasites to rapidly transform disease phenotypes and exploit new host populations. Trypanosoma cruzi, the parasitic agent of Chagas disease and a public health concern throughout Latin America, has for decades been presumed to exchange genetic material rarely and without classic meiotic sex. We present compelling evidence from 45 genomes sequenced from southern Ecuador that T. cruzi in fact maintains truly sexual, panmictic groups that can occur alongside others that remain highly clonal after past hybridization events. These groups with divergent reproductive strategies appear genetically isolated despite possible co-occurrence in vectors and hosts. We propose biological explanations for the fine-scale disconnectivity we observe and discuss the epidemiological consequences of flexible reproductive modes. Our study reinvigorates the hunt for the site of genetic exchange in the T. cruzi life cycle, provides tools to define the genetic determinants of parasite virulence, and reforms longstanding theory on clonality in trypanosomatid parasites.
We describe a new species of frog of the genus Chiasmocleis from the montane forests of southeastern Ecuador, at the western slopes of Cordillera del Cóndor, between 1,224 1,630 m of elevation. Based on new sequences of mitochondrial and nuclear DNA we present phylogenetic relationships of the new species and its congeners. The phylogeny shows a close relationship to C. antenori, C. carvalhoi, C. magnova and C. tridactyla. The new species is part of a clade of species that were previously assigned to the genus Syncope. This clade has a sister relationship to a clade that contains all remaining species of Chiasmocleis. The new species differs from its congeners by its reddish-brown to dark-brown (sepia) dorsum with minute yellowish-white spots. Chiasmocleis parkeri sp. nov. is similar to Chiasmocleis antenori in lacking digit I of both hands and feet but Chiasmocleis parkeri differs in coloration, arrangement and size of pale spots, and the absence of a pale line in the canthal region. We describe the calls, which are characterized by having non-pulsed notes, and we provide ecological data from the type locality and adjacent areas.
A finales del año pasado se reportaron casos de pacientes con neumonía atípica en Wuhan, Provincia de Hubei, China. La mayoría de pacientes iniciales trabajaban, vivían o eran consumidores de productos del mercado mayorista de mariscos, lo que sugirió un posible contagio de un patógeno de origen animal al ser humano. Posteriormente, se determinó que el responsable fue un coronavirus, que se llamó SARS-CoV-2, cuya rápida propagación produjo la pandemia de la enfermedad coronavirus disease 19 (COVID-19). La enfermedad es actualmente motivo de preocupación e intensa investigación a nivel mundial. Se han postulado teorías sobre el origen del coronavirus, siendo la más aceptada que el virus proviene del pangolín malayo. Con la finalidad de reforzar esta teoría, en la presente investigación, a partir de secuencias nucleotídicas de dominio público, se seleccionaron fragmentos de secuencias nucleotídicas que codifican para la espícula glicoprotéica superficial de coronavirus en algunos organismos hospederos infectados por diferentes cepas de coronavirus incluyendo el SARS-CoV-2. De la filogenia y análisis de secuencias de aminoácidos de la espícula glicoprotéica del coronavirus se encontró posibles eventos de transmisión entre especies del virus responsable de la enfermedad incluyendo el ser humano.
A finales del año pasado se reportaron casos de pacientes con neumonía atípica en Wuhan, Provincia de Hubei, China. La mayoría de pacientes iniciales trabajaban, vivían o eran consumidores de productos del mercado mayorista de mariscos, lo que sugirió un posible contagio de un patógeno de origen animal al ser humano. Posteriormente, se determinó que el responsable fue un coronavirus, que se llamó SARS-CoV-2, cuya rápida propagación produjo la pandemia de la enfermedad coronavirus disease 19 (COVID-19). La enfermedad es actualmente motivo de preocupación e intensa investigación a nivel mundial. Se han postulado teorías sobre el origen del coronavirus, siendo la más aceptada que el virus proviene del pangolín malayo. Con la finalidad de reforzar esta teoría, en la presente investigación, a partir de secuencias nucleotídicas de dominio público, se seleccionaron fragmentos de secuencias nucleotídicas que codifican para la espícula glicoprotéica superficial de coronavirus en algunos organismos hospederos infectados por diferentes cepas de coronavirus incluyendo el SARS-CoV-2. De la filogenia y análisis de secuencias de aminoácidos de la espícula glicoprotéica del coronavirus se encontró posibles eventos de transmisión entre especies del virus responsable de la enfermedad incluyendo el ser humano.
We investigate whether the Amotape—Huancabamba zone in the Andes acts as a barrier or corridor for plant species migration. We test this hypothesis based on data on trees, shrubs, and herbs collected in dry inter-Andean valleys (DIAVs) of Ecuador. We found that 72% of the species cross the Amotape—Huancabamba zone in a north—south direction and 13% of the species cross the Andes in an east—west direction. Southern DIAVs concentrate the highest numbers of endemic species. At the regional level we found that 43% of the species are exclusively Andean, while the remaining 57% are found in the Pacific lowlands, the Caribbean, and Mesoamerica. These results showing many species crossing the Amotape—Huancabamba zone in a north—south direction and also frequently found in neighboring lowland and highland ecosystems suggest that the Amotape—Huancabamba zone acts as a corridor for species migration of dry inter-Andean flora.
El presente estudio corresponde a la evaluación de la calidad del agua del río Pita y sus afluentes ubicados dentro y fuera del Parque Nacional Cotopaxi. Se fijaron siete estaciones de monitoreo, en las cuales se recolectaron muestras aguas arriba y abajo de cada afluente, en abril de 2018 y abril de 2019. Se midieron parámetros físicoquímicos in situ como: pH, temperatura y porcentaje de saturación de oxígeno disuelto (OD); se analizaron los parámetros establecidos en la normativa ambiental ecuatoriana: Texto Unificado de la Legislación Secundaria del Ministerio del Ambiente, TULSMA, Anexo 1, Libro VI, tabla 2, aplicando métodos de análisis de acuerdo al Standard Methods for the Examination of Water and Wastewater (APHA). Los resultados indican que las muestras recolectadas superan el límite permisible para fenoles (0,001 mg·dm-3) establecido en el TULSMA, a excepción del río Hualpaloma, mientras que para el caso de hierro, todas las muestras del cauce del río Pita y sus afluentes sobrepasan el límite permisible (0,3 mg·dm-3 ). A partir de los resultados obtenidos, las muestras recolectadas del río Pita cumplen con los criterios de calidad de agua establecidos para la conservación de la vida acuática y silvestre, a pesar de atravesar zonas urbanas, donde diariamente existen descargas domésticas e industriales por tratarse de un canal abierto. Finalmente, de acuerdo al índice de calidad del agua aplicado (ICA-NSF), los afluentes ubicados dentro del parque Nacional Cotopaxi presentaron una “calidad buena”, mientras que los afluentes ubicados fuera del Parque Nacional presentaron una “calidad media” relacionada con la cercanía a zonas urbanas.
The effect of carbonate impurities in the photoluminescence (PL) properties of hydroxyapatite has been studied. Different hydroxyapatite samples were synthesized by chemical precipitation with some differences in the purity of the precursors or the final neutralization treatment. All the materials were calcined in the temperature range of 200–800 °C. Calcination treatments in the range of 400–450 °C resulted in intense and broad luminescence spectra. Especially high PL intensity was obtained in samples HaB which was neutralized with phosphoric acid and in HaD a carbonated apatite. The band gap of these samples was in the range of 3.1–3.96 eV. The materials were characterized by Fourier Transformed Infrared spectroscopy, scanning and transmission electron microscopy, differential scanning calorimetry and x-ray diffraction. The time resolved luminescence decay was in the range from 500 to 980 ms in samples HaB, for calcination temperatures from 400 to 500 °C. The PL properties of these non-toxic materials made them very promising for new optical applications.
Nowadays, the increasing pollution of natural water effluents with textile dyes is an emerging problem that has not received attention enough. This work presents a study on the preparation of two Ti/IrO2-SnO2-Sb2O5 electrodes so-called E1 and E2 with 0.01 and 0.09 wt% of Sb dopant, respectively, by the Pechini method. The characteristics of these electrodes were analyzed by scanning electron microscopy-energy dispersive X-ray spectroscopy and X-ray diffraction. The E2 anode possessed a higher electroactivity and produced more largely hydroxyl radicals in electrochemical oxidation (EO). The action of this oxidant, along with active chlorine of textile dyes like Violet RL, Green A and Brown DR was assessed in 50 mM Na2SO4 and 10 mM NaCl at pH 3.0 by EO with the E2 anode. It was found that the discoloration of 80 mg L−1 of each individual solution was enhanced with increasing the current density from 25 to 50 mA cm−2, always obeying a pseudo-first-order kinetics. The process was faster in the sequence: Green A < Brown DR < Violet RL, and at 50 mA cm−2, a loss of color > 86% of color was attained in only 6 min. A mixture with 80 mg L−1 of each dye was treated under analogous EO conditions, giving rise to 100% discoloration in 20 min and about 90% chemical oxygen demand removal in 60 min at 50 mA cm−2. Three carboxylic acids, maleic, oxalic and oxamic, were detected as final byproducts by ion-exclusion high-performance liquid chromatography. The results reported in this work demonstrate the large effectiveness of the synthesized Ti/IrO2-SnO2-Sb2O5 electrodes to remove textile azo dyes, with higher rate constants than usual anodes.
In recent decades, a renewed interest in comparative studies of embryonic ontogeny in anurans is taking place. Toad embryos are often employed as model organisms, and scarce attention has been put on interspecific variations. In this work we analyze the development of transient embryonic and larval structures in 21 species in five genera of Bufonidae. These species vary in their ovipositional mode and the type of environments where the embryos and tadpoles develop, including ponds, streams, and axils of leaves of terrestrial or epiphytic plants. Comparative anatomical studies and sequence heterochrony analyses show that primary morphological variations occur in the morphology at the tail-bud stage, the arrangement and development of the external gills, adhesive gland type and division timing, growth of the dorsal hatching gland on the head, configuration of the oral disc, emergence and development of the hind limbs, and presence of the abdominal sucker. Some of these transformations are best explained by phylogeny (e.g., early divergent taxa of bufonids have embryos with kyphotic body curvature, Type C adhesive glands, and a very small third pair of gills). Other traits might be correlated with reproductive modes (e.g., phytotelmata embryos hatch comparatively late and show an accelerated development of hind limbs). Because these actual variations are not well studied (e.g., less than the 10% of the known diversity of bufonids has been studied from this perspective), comprehensive analyses are required to interpret character evolution and the relationship with reproductive modes within the family.
Ecnomiohyla tuberculosa is an Amazonian hylid of uncertain phylogenetic position. Herein DNA sequences of mitochondrial and nuclear genes are used to determine its phylogenetic relationships. New sequences and external morphology of Trachycephalus typhonius are also analyzed to assess the status of Ecuadorian and Peruvian populations. The phylogeny shows unequivocally that Ecnomiohyla tuberculosa is nested within the genus Tepuihyla, tribe Lophiohylini. This position was unexpected because the remaining species of Ecnomiohyla belong to the tribe Hylini. To solve the paraphyly of the genus Ecnomiohyla, E. tuberculosa is transferred to the genus Tepuihyla. Comparisons of DNA sequences, external morphology, and advertisement calls between populations of Ecnomiohyla tuberculosa from Ecuador and Peru indicate that the Peruvian population represents an undescribed species. The new species is described and a species account is provided for Ecnomiohyla tuberculosa. Trachycephalus typhonius is paraphyletic relative to T. cunauaru, T. hadroceps, and T. resinifictrix. The phylogenetic position of populations from western Ecuador indicates that they represent a species separate from T. typhonius sensu stricto. We resurrect the name Hyla quadrangulum (Trachycephalus quadrangulum comb. n.) for those populations. Amazonian populations of “T. typhonius” from Ecuador and Peru are genetically and morphologically distinct from T. typhonius sensu stricto and are conspecific with the holotype of Hyla macrotis. Therefore, we also resurrect Hyla macrotis, a decision that results in Trachycephalus macrotis comb. n.
In the aseasonal tropical alpine environment, plants experience frequent oscillations of air temperature around zero, but little is known about the leaf temperatures of different plant growth forms in dry versus humid climatic conditions. During July-August 2007, we measured air temperature at 100 cm and 20 cm above the ground, soil temperature at 1 cm and 10 cm depth, and temperatures of leaves and stems of tropical alpine plants on the eastern (windward and cloudy) and western (leeward and sunny) sides of the Antisana volcano (Ecuador) between 4100 m and 4600 m, with the aim of examining the effects of climate and growth forms on leaf temperature. The sunnier climate on the western side of the mountain provided a much broader thermal envelope, in which only leaves of low-statured plants showed significant departure from air temperature during the day. In contrast, most plants had warmer leaves than was the air temperature on the eastern side, and except for cushion plants, the difference in temperature was progressively greater in leaves of taller plants. Plants warmed up significantly faster on the western side and at higher elevations, with the fastest warming rates of 13-15 K h⁻¹ observed in erect herbs. Night cooling rates did not differ between the opposite mountain sides or between elevations. Erect herbs cooled at the fastest rates (3 K h⁻¹), whereas cushion plants cooled at the slowest rates (about 1 K h⁻¹).
In recent years several extensions and generalizations have been considered for classical convexity, and the theory of inequalities has made essential contributions to many areas of Mathematics. In this paper we shall deal with an important and useful class of functions called operator convex functions. We introduce anew class of generalized convex functions, namely the class of operator h-convex function. The theory of operator/matrix monotone functions was initiated by the celebrated paper of C. L ̈owner, which was soon followed by F. Kraus  on operator/matrix convex functions. After further developments due to some authors (for instance, J. Bendat and S. Sherman , A. Kor ́anyi , and U. Franz), in their seminal paper  F. Hansen and G.K. Pedersen established a modern treatment of operator monotone and convex functions.
We explored mechanisms determining the upper altitudinal limit of ephemeropterans from two different genera: Leptohyphes Eaton, 1882 (Leptohyphidae) and Lachlania Hagen, 1868 (Oligoneuriidae). For this, we (1) surveyed the two taxa in 165 stream sites along a wide altitudinal gradient; (2) sampled benthic fauna at short altitudinal intervals along a stream, from 2780 to 3150 m above sea level; (3) collected adults at the lowest and highest sites; and (4) transplanted nymphs from the lowest to the highest study site in our stream to determine survival over time. Densities of the two taxa declined gradually with altitude and both disappeared between 2950 and 3080 m a.s.l. The upper altitudinal limit in the stream seemed to be most closely related to mean oxygen saturation, temperature, and current velocity. Adults were collected where the nymphs were found, but not at the upstream site where the nymphs were absent, implying limited upstream dispersal of adults and some of the altitudinal constraint lying at the adult stage. Short-term survival of transplanted nymphs was lower than that of controls, suggesting that the distribution was limited at the juvenile stage, and that at least some of the altitudinal constraint is related to the abiotic stream environment.
BIRM is an anticancer herbal formulation from Ecuador. Previous study established its antitumor and antimetastatic activity against prostate cancer models. The activity of BIRM against human prostate cancer (PCa) cells was investigated to uncover its mechanism of antitumor activity. In androgen receptor (AR)-expressing PCa cells BIRM was 2.5-fold (250%) more cytotoxic in presence of androgen (DHT) compared to cells grown in the absence of DHT. In AR-positive cells (LAPC-4 and LNCaP) BIRM caused a dose and time-dependent down-regulation of AR and increased apoptosis. Exposing cells to BIRM did not affect the synthesis of AR and AR promoter activity but increased degradation of AR via proteasome-pathway. BIRM caused destabilization of HSP90-AR association in LAPC-4 cells. It induced apoptosis in PCa cells by activation of caspase-8 via death receptor and FADD-mediated pathways. A synthetic inhibitor of Caspase-8 cleavage (IETD-CHO) aborted BIRM-induced apoptosis. The effect of BIRM on AKT-mediated survival pathway in both AR+ and AR- negative (PC-3 and DU145) showed decreased levels of p-AKTser 473 in all PCa cell lines. BIRM dosed by oral gavage in mice bearing PC-3ML tumors showed selective efficacy on tumor growth; before tumors are established but limited efficacy when treated on existing tumors. Moreover, BIRM inhibited the LNCaP tumor generated by orthotropic implantation into dorsal prostate of nude mice. Partial purification of BIRM by liquid-liquid extraction and further fractionation by HPLC showed 4-fold increased specific activity on PCa cells. These results demonstrate a mechanistic basis of anti-tumor activity of the herbal extract BIRM.
En este articulo demostraremos un teorema de existencia y unicidad para un sistema de ecuaciones lineales que incluye como consecuencia a los Modelos de Volterra.
Fungal endophytes colonize every major lineage of land plants without causing apparent harm to their hosts. Despite their production of interesting and potentially novel compounds, endophytes—particularly those inhabiting stem tissues—are still a vastly underexplored component of microbial diversity. In this study, we explored the diversity of over 1500 fungal endophyte isolates collected from three Ecuadorian ecosystems: lowland tropical forest, cloud forest, and coastal dry forest. We sought to determine whether Ecuador’s fungal endophytes are hyperdiverse, and whether that biological diversity is reflected in the endophytes’ chemical diversity. To assess this chemical diversity, we analyzed a subset of isolates for their production of volatile organic compounds (VOCs), a representative class of natural products. This study yielded a total of 1526 fungal ITS sequences comprising some 315 operational taxonomic units (OTUs), resulting in a non-asymptotic OTU accumulation curve and characterized by a Fisher’s α of 120 and a Shannon Diversity score of 7.56. These figures suggest that the Ecuadorian endophytes are hyperdiverse. Furthermore, the 113 isolates screened for VOCs produced more than 140 unique compounds. These results present a mere snapshot of the remarkable biological and chemical diversity of stem-inhabiting endophytic fungi from a single neotropical country.
Context Natural regenerating forests are rapidly expanding in the tropics. Forest transitions have the potential to restore biodiversity. Spatial targeting of land use policies could improve the biodiversity benefits of reforesting landscapes. Objective We explored the relative importance of landscape attributes in influencing the potential of tree cover increase to restore native woody plant biodiversity at the landscape scale. Methods We developed land use scenarios that differed in spatial patterns of reforestation, using the Pangor watershed in the Ecuadorian Andes as a case study. We distinguished between reforestation through natural regeneration of woody vegetation in abandoned fallows and planted forests through managed plantations of exotic species on previously cultivated land. We simulated the restoration of woody plant biodiversity for each scenario using LANDIS-II, a process-based model of forest dynamics. A pair-case comparison of simulated woody plant biodiversity for each scenario was conducted against a random scenario. Results Species richness in natural regenerating fallows was considerably higher when occurring in: (i) close proximity to remnant forests; (ii) areas with a high percentage of surrounding forest cover; and (iii) compositional heterogeneous landscapes. Reforestation at intermediate altitudes also positively affected restoration of woody plant species. Planted exotic pine forests negatively affected species restoration. Conclusions Our research contributes to a better understanding of the recolonization processes of regenerating forests. We provide guidelines for reforestation policies that aim to conserve and restore woody plant biodiversity by accounting for landscape attributes.
Background The Shiny Cowbird, Molothrus bonariensis Gmelin, 1789, is a brood parasite of hundreds of small-bodied birds that is native to South American lowlands. Within the last 100 years this species has been expanding its range throughout the Caribbean, towards North America, but has rarely been seen above 2,000 m asl. New information Here, we present records of Shiny Cowbirds in Quito, a city located 2,800 m above sea level that harbors a bird community typical of the Andean valleys. We found two juvenile individuals parasitizing two different pairs of Rufous-collared Sparrow (Zonotrichia capensis Müller, 1776). This report constitutes an altitudinal range expansion of reproductive populations of ca. 500m, which may have beenprompted by anthropogenic disturbance.
The mechanism of Alder-ene reactions between n-hexene and heptanal and n‑tetradecene and heptanal was characterized using reaction force, reaction force constant and reaction electronic flux concepts. Density-functional theory studies were performed at the B3LYP/6-311G(d,p) level. Structural analysis shows the changes in bond angles and distances throughout the reaction path. Thermodynamic analyses suggest these reactions are exothermic with activation energies between 21.1 and 34.2 kcal/mol. The proposed mechanisms follow three basic reaction steps in the transformation from reagents to products. First, the hydrogen shift from the ene to the enophile. Then, there is an electronic rearrangement produced by π and σ electrons. Finally, σ-bond formation and structural relaxation occur, leading to the final product. The mechanism found, based on the quantum descriptors, was confirmed to be the right one.
Protein expression of the transcription factor genes mix1 and vegt characterized the presumptive endoderm in embryos of the frogs Engystomops randi, Epipedobates machalilla, Gastrotheca riobambae, and Eleutherodactylus coqui, as in Xenopus laevis embryos. Protein VegT was detected in the animal hemisphere of the early blastula in all frogs, and only the animal pole was VegT-negative. This finding stimulated a vegt mRNA analysis in X. laevis eggs and embryos. vegt mRNA was detected in the animal region of X. laevis eggs and early embryos, in agreement with the VegT localization observed in the analyzed frogs. Moreover, a dorso-animal relocalization of vegt mRNA occurred in the egg at fertilization. Thus, the comparative analysis indicated that vegt may participate in dorsal development besides its known roles in endoderm development, and germ-layer specification. Zygotic vegt (zvegt) mRNA was detected as a minor isoform besides the major maternal (mvegt) isoform of the X. laevis egg. In addition, α-amanitin–insensitive vegt transcripts were detected around vegetal nuclei of the blastula. Thus, accumulation of vegt mRNA around vegetal nuclei was caused by relocalization rather than new mRNA synthesis. The localization of vegt mRNA around vegetal nuclei may contribute to the identity of vegetal blastomeres. These and previously reportedly localization features of vegt mRNA and protein derive from the master role of vegt in the development of frogs. The comparative analysis indicated that the strategies for endoderm, and dorsal specification, involving vegt and mix1, have been evolutionary conserved in frogs.
We describe two new species of frogs of the genus Pristimantis from the eastern slopes of the Ecuadorian Andes, at Parque Nacional Llanganates. The new species are characterized by the spiny appearance typical of several species inhabiting montane forests. Pristimantis yanezi sp. n. is most similar to P. colonensis and P. incanus but differs from both in groin coloration and by having smaller tubercles on the upper eyelids, heels, and tarsus. Pristimantis llanganati sp. n. is most similar to P. eriphus and P. chloronotus. It can be distinguished from P. eriphus by the color pattern on the scapular region and by having smaller conical tubercles on the dorsum. Pristimantis chloronotus differs from P. llanganati sp. n. in having a pair of sinuous paravertebral folds. Both new species occur in a region with few amphibian collections and nothing is known about their abundance and ecology. Therefore, it is recommended to assign them to the Data Deficient Red List category. Updated figures of species richness of Pristimantis among biogeographic regions in Ecuador are also presented. Pristimantis reach their highest diversity in Montane Forests of the eastern versant of the Andes. Its species richness across regions cannot be explained by regional area, elevation, temperature, or precipitation. Political endemism in Pristimantis is higher than that of other terrestrial vertebrates.
Dactylonectria and Campylocarpon are two related genera of Hypocreales sharing a cylindrocarpon-like asexual morph, mostly known as soil-borne pathogens. During a study of the fungal communities of roots (endophyte) and rhizoplanes of plants growing in a layer of compost-like vegetal materials covering crude oil ponds in rain forest areas of the Amazonian Ecuador, a set of isolates with a cylindrocarpon-like asexual morph were studied. Multilocus phylogenetic inferences (based on partial DNA sequences from nuclear ribosomal DNA genes (ITS, 28S) and the housekeeping genes b-tubulin, translation elongation factor 1-α and Histone 3) and morphological studies revealed the occurrence of five undescribed species, of which four belong to Dactylonectria and one to Campylocarpon. They are described as Dactylonectria amazonica, D. ecuadoriense, D. polyphaga, D. palmicola and Campylocarpon amazonense.
Se describen dos especies nuevas del género Drosophila. Estas especies fueron capturadas en el bosque protector Yanacocha, ubicado en el noroccidente del volcán Pichincha. Drosophila yanacocha sp. nov., fue recolectada a 3 587msnm y es miembro del grupo de D. annulimana. Mientras que Drosophila papaver sp. nov., fue encontrada a 3 771msnm. Esta especie fue imposible ubicarla en un grupo de especies, por lo tanto permanece como no agrupada. Sin embargo la espermateca de D. papaver sp. nov., tiene cierto parecido con la espermateca de D. pictifrons Duda (1927) lo que sugeriría que podrían estar relacionadas.
In a equalispora and Parvothecium are two myrothecium-like, closely related genera of Hypocreales. They are also morphologically similar, sharing sporodochial conidiomata, penicillate conidiophores, fusiform to ellipsoidal conidia accumulating in a green slimy drop, and hypha-like setoid extensions emerging through the conidial mass. During a revision of myrothecium-like isolates originating from rainforest areas of South America (Ecuador, Brazil) and Southeast Asia (Singapore), multilocus phylogenetic inferences (based on DNA sequence data of ITS, partial nuc 28S, and partial tef1a, rpb2 and tub2) and morphological studies concordantly revealed the occurrence of two undescribed species of Inaequalispora (I. longiseta sp. nov. and I. cylindrospora sp. nov.) and one undescribed species of Parvothecium (P. amazonensesp. nov.). Myrothecium setiramosum, M. dimorphum, and two undescribed taxa form the base of a new lineage, sister to the current Parvothecium lineage. This lineage is recognized as Digitiseta gen. nov., typified by D. setiramosa comb. nov. Digitiseta dimorpha comb. nov. is also proposed, and the new species
The hyline tribe Lophyohylini includes 87 species of treefrogs, of which cytogenetics aspects have been studied in less than 20% of them. In order to evaluate the evolution of some of its chromosome characters (NOR position, C-bands, and DAPI/CMA3 bands), we studied the karyotypes of 21 lophyohylines, 16 of them for the first time, and analyzed them in a phylogenetic context. Most species showed similar karyotypes regarding chromosome number (2n = 24) and morphology (FN = 48), excepting Phyllodytes edelmoi and Osteocephalus buckleyi with 2n = 22 (FN = 44) and 2n = 28 (FN = 50), respectively. The NOR location was variable among species and provided valuable phylogenetic information. This marker was located in pair 11 in all species of Trachycephalus, Itapotihyla langsdorffii, and Nyctimantis arapapa, representing the plesiomorphic condition of Lophyohylini. Besides, other apomorphic states were recovered for the clades comprising N. rugiceps and N. siemersi (NOR in pair 5), and Dryaderces pearsoni, Osteocephalus, and Osteopilus (NOR in pair 9). Phyllodytes presented variation for NORs position; they were in pair 2 in P. edelmoi, pair 7 in P. melanomystax, and pair 8 in P. gyrinaethes and P. praeceptor. Polymorphisms in size, number, and activity of this marker were observed for N. siemersi, Osteocephalus fuscifacies, and some species of Trachycephalus. Remarkably, in N. siemersi NORs were detected on a single chromosome in the two specimens studied by this technique, raising the question of how this complex polymorphism is maintained. Interstitial telomeric sequences were found in P. edelmoi, P. melanomystax, and Osteocephalus buckleyi, and their presence seems to be not related to the chromosome reorganization events. Finally, some species showed spontaneous rearrangements, possibly as a consequence of an uncommon phenomenon in anuran cytogenetics: the presence of fragile sites or secondary constrictions not associated with NORs. We propose that this rare feature would have played an important role in the evolution of this group of frogs. From the evidence obtained in this and previous studies, we conclude that Lophyohylini presents a complex chromosome evolution.
Although the central coast of the Ecuador is considered endemic for Chagas disease, few studies have focused on determining the risk of transmission in this region. In this study we describe the triatomine household infestation in Manabí province (Central Coast region), determine the rate of Trypanosoma cruzi infection and study the risk factors associated with infestation by Rhodnius ecuadoriensis.
Delia platura Meigen is an important pest in crops around the world. Its host range includes almost 50 species, and it can develop in soil organic matter. In Ecuador, D. platura is a serious problem for the crop, Lupinus mutabilis Sweet (Chocho), and it also attacks broccoli (Brassica oleracea L.). After broccoli is harvested, crop residue is mixed with soil or collected and stored close to Chocho fields. The objectives of this study were to determine the adaptive responses of larvae reared on different hosts and whether D. platura females are preferentially attracted to germinating L. mutabilis seeds or broccoli residue. Accordingly, larval performance and attraction of female D. platura reared on broccoli residue and L. mutabilis seeds were evaluated. The number of larvae, pupae, and adults were higher when reared on broccoli. Conversely, pupal weight was higher and time from larva to pupa, pupa to adult, and total life cycle were longer in flies reared on L. mutabilis. Although D. platura developed more quickly on broccoli, L. mutabilis was also a good host since pupae were heavier compared with flies reared on broccoli. Delia platura females reared on broccoli preferred broccoli residue to L. mutabilis in an olfactometer. Volatiles from broccoli residue in soil may attract D. platura females and stimulate oviposition on L. mutabilis seeds. Environmentally benign production of L. mutabilis crops with minimal insecticide applications may require the elimination of fresh broccoli residue as fertilizer in soils where L. mutabilis is cultivated.
Forests dominated by Polylepis pauta occur in humid environments in the high Andes of Ecuador, Peru and Bolivia, at elevations between 3500–4500 m. Polylepis forests host a unique biodiversity of plants and animals and are an important supply of resources for local people. However, these forests are being destroyed by extensive burning practices, causing the replacement of the forest by grassland and favoring cattle grazing. As a consequence, Polylepis forests have become severely diminished and fragmented, and are considered as one of the most threatened ecosystems in South America. The vascular flora of Ecuadorian P. pauta forests has been documented in detail but little is known about bryophytes of these forests. This paper deals with the liverwort flora of remnant P. pauta forests in the páramo of Papallacta near Quito, Ecuador. The forest floor and trunk bases were almost completely covered by Lepidozia auriculata and four robust Plagiochila species (P. dependula, P. ensiformis, P. fuscolutea, P. ovata). Frullania paradoxa, Leptoscyphus hexagonus, Plagiochila bifaria and P. punctata were abundant on branches of Polylepis trees. In total 51 liverworts were recorded, being the highest number of liverwort species reported from Polylepis forest. Leptoscyphus leoniae Gradst. and Plagiochila pautaphila Gradst. & León-Yánez are new to science.
Novel species of fungi described in this study include those from various countries as follows: Australia: Banksiophoma australiensis (incl. Banksiophoma gen. nov.) on Banksia coccinea, Davidiellomyces australiensis (incl. Davidiellomyces gen. nov.) on Cyperaceae, Didymocyrtis banksiae on Banksia sessilis var. cygnorum, Disculoides calophyllae on Corymbia calophylla, Harknessia banksiae on Banksia sessilis, Harknessia banksiae-repens on Banksia repens, Harknessia banksiigena on Banksia sessilis var. cygnorum, Harknessia communis on Podocarpus sp., Harknessia platyphyllae on Eucalyptus platyphylla, Myrtacremonium eucalypti (incl. Myrtacremonium gen. nov.) on Eucalyptus globulus, Myrtapenidiella balenae on Eucalyptus sp., Myrtapenidiella eucalyptigena on Eucalyptus sp., Myrtapenidiella pleurocarpae on Eucalyptus pleurocarpa, Paraconiothyrium hakeae on Hakea sp., Paraphaeosphaeria xanthorrhoeae on Xanthorrhoea sp., Parateratosphaeria stirlingiae on Stirlingia sp., Perthomyces podocarpi (incl. Perthomyces gen. nov.) on Podocarpus sp., Readeriella ellipsoidea on Eucalyptus sp., Rosellinia australiensis on Banksia grandis, Tiarosporella corymbiae on Corymbia calophylla, Verrucoconiothyrium eucalyptigenum on Eucalyptus sp., Zasmidium commune on Xanthorrhoea sp., and Zasmidium podocarpi on Podocarpus sp.
Considering worldwide amphibian population decline, sperm cryopreservation should be a priority for conservation of species in areas of high biodiversity, such as the Neotropics. In this study, we present the results of two cryopreservation experiments involving Rhinella marina sperm. Freezing was performed in a -80 °C freezer and dimethyl sulfoxide (DMSO) was used as cryoprotective agent. In the first experiment, the effects of 5%, 10%, and 15% DMSO were evaluated in sperm lysis and fertilization capacity. Samples were incubated for 10 minutes at 4 °C before freezing. For thawing, two procedures were tested: 21 °C thawing to be used immediately and 4 °C thawing, to be used two hours later in in vitro fertilizations. The best treatment was 10% DMSO plus thawing at 4 °C, that achieved 20% successful fertilizations. In the second experiment, two solutions were tested: 10% DMSO with and without HEPES. Freezing and post-thawing in vitro fertilizations were performed after a two hour incubation period at 4 °C. A considerable improvement in fertilization percentages was obtained in this experiment, with a 75% for DMSO alone, and a 70% for DMSO + HEPES. These results provide good perspectives for future implementation of sperm cryopreservation in Neotropical institutions for local threatened species.
Ecuador’s territory harbors a unique set of species and ecosystems, many of them endemic to the countries’ territory and subject to different sources of threat of anthropogenic origin. Despite national and subnational conservation strategies developed in Ecuador to conserve its biodiversity in the long run, including the National System of Protected Areas (PANE) and the forest conservation incentive program SocioBosque (PSB), further actions are needed to mitigate and reverse the effects of threats for the persistence of biodiversity. This study was designed to identify the most important areas for biodiversity conservation in mainland Ecuador that can contribute to preserving key species (i.e. endemic, threatened) and ecosystems in the wider landscape, thus complementing current conservation efforts (i.e. PANE). Species distribution models and recent maps were used to identify a set of 744 species and 87 ecosystems as surrogates of the country’s biodiversity. Marxan, a systematic reserve selection algorithm was used to identify important biodiversity areas that could represent between 10% and 20% of the remnant distribution of the surrogates. The optimized solution generated by Marxan included 24% (3.64 million ha) of Ecuador′s remnant vegetation, of which 35% is within the current national protected area system and 13% (456 000 ha) are included within SocioBosque communal and private conservation agreements. Major conservation shortfalls of the PANE were concentrated in the Southern Andes, Central Amazonia, and the Central and Southern portions of the Coastal plain.
Congenital infection with Trypanosoma cruzi remains a major route for Chagas disease transmission in endemic and non-endemic regions. We evaluated an intervention strategy aimed to detect congenital Chagas disease cases at a major hospital in the Ecuadorian Amazon via cord blood analysis at the time of delivery. Allwomengiving birth at the hospital during the study period (191) were invited to participate. Among them, two (1.0%) did not adjust to the inclusion criteria and four (2.1%) declined to participate in the study, showing the intervention had good acceptability among the mothers. It was possible to obtain cord blood samples during 146 of the deliveries, and only one woman was found to be seropositive, without evidence of transmission to the newborn at delivery or 8 months later. In addition, sociodemographic and economic characterization of the study population revealed that few women had previous knowledge about Chagas disease (16.1%) whereas more than half (62.5%) recognized the vector. Recognizing the vector and having seen it indoors were associated with women from rural families, involved in agriculture, and hunting in the forest. Interestingly, most women (87.3%) reported having easy access to Ecuador's national health system, suggesting serological screening during prenatal visits would be of value in this province. With a proper prenatal screening system in place, cord blood screening would allow for timely detection of T. cruzi infection in newborns from both seropositive women and the minority (2.1%) of women who do not comply with prenatal care visits.
Se realizó un diagnóstico de la eficiencia de remoción de contaminantes en la planta de tratamiento de aguas residuales (PTAR) de la ciudad de Manta, la cual recibe en promedio un caudal de 30798 m3d-1 de agua residual. Para ello se caracterizó fisicoquímicamente el agua durante el tratamiento, determinándose eficiencias de remoción de DBO5 del 51 % y de DQO del 56 %, valores que, al ser comparados con otras PTAR del mismo tipo, indican una pobre remoción de materia orgánica. Con respecto al efluente de descarga del sistema, se encontró que los parámetros DQO, DBO5, nitrógeno Kjeldahl y sólidos totales, sobrepasan los límites máximos permisibles de la normativa ecuatoriana. En conclusión, se demostró que el sistema requiere mantenimiento especialmente en las lagunas facultativas, ya que son las principales responsables de la disminución de la eficiencia global de remoción de contaminantes.
It remains poorly understood how the composition of leaf wax n -alkanes reflects the local environment. This knowledge gap inhibits the interpretation of plant responses to the environment at the community level and, by extension, inhibits the applicability of n - alkane patterns as a proxy for past environments. Here, we studied the n - alkane patterns of five Miconia species and one Guarea species , in the Ecuadorian Andes (653–3,507 m a.s.l.). We tested for species - specific responses in the average chain length (ACL), the C /(C + C ) ratio (ratio), and individual odd n - alkane chain lengths across an altitudinally driven environmental gradient (mean annual temperature, mean annual relative air humidity, and mean annual precipitation). We found significant correlations between the environmental gradients and species - specific ACL and ratio, but with varying magnitude and direction. We found that the n - alkane patterns are species - specific at the individual chain length level, which could explain the high variance in metrics like ACL and ratio. Although we find species - specific sensitivity and responses in leaf n -alkanes, we also find a general decrease in “shorter” (C ) chain lengths with the environmental gradients, most strongly with temperature, suggesting n -alkanes are useful for reconstructing past environments.
River ecosystems receive and process vast quantities of terrestrial organic carbon, the fate of which depends strongly on microbial activity. Variation in and controls of processing rates, however, are poorly characterized at the global scale. In response, we used a peer-sourced research network and a highly standardized carbon processing assay to conduct a global -scale field experiment in greater than 1000 river and riparian sites. We found that Earth's biomes have distinct carbon processing signatures. Slow processing is evident across latitudes, whereas rapid rates are restricted to lower latitudes. Both the mean rate and variability decline with latitude, suggesting temperature constraints toward the poles and greater roles for other environmental drivers (e.g., nutrient loading) toward the equator. These results and data set the stage for unprecedented "next-generation biomonitoring" by establishing baselines to help quantify environmental impacts to the functioning of ecosystems at a global scale.
Research and conservation of palm species relies on training new generations of palm biologists, especially in tropical countries. Such trainings pave the way to answer new questions related to palm biology, sustainable management, the cultural and economic links between humans and palms, and build conservation strategies through education and civil empowerment.
Phytelephas aequatorialis is the commercially exploited ivory palm in western Ecuador, where less than 25% of the natural forest remains. To determine the conservation status of this palm, we visited 15 populations, growing under different degrees of human disturbance in both the lowlands and the lower Andean slopes. We collected leaf material for genetic analyses, which we hope will provide valuable information that can help the conservation and management of this important species. For a first view, populations growing outside forests in pastures appeared to be threatened because they did not reproduce naturally. The species per se, however, is not threatened because of its wide distribution and large populations. Conserving its populations could secure the species’ genetic and phenotypic diversity, which, in turn, is the raw material for its domestication.
In the Tropical Andes millions of people depend upon the use of wild and domesticated biodiversity for their livelihoods, but the complex interactions between the ecological and social components of the region’s ecosystems remain poorly under‐ stood. Better knowledge of these interactions can help provide solutions to reduce poverty in this region. The joint international laboratory on Biodiversity in Natural and Cultivated phytosystems of the Tropical Andes (BIO_INCA) aims to fill crucial gaps in knowledge by advancing research at the interface between biology, ecology, agronomy, social and human science, and economics, which will not only help address the challenge of ecologically sustainable agriculture, but also contribute to United Nations sustainable development goals on Zero hunger and Life on land.
We analyze the statistical averages over a set of realizations of the random variable in the Stochastic Optical Bloch equations, using Novikov's sufficient condition theorem. We consider a system on an adiabatic basis interacting with an external field in the presence of a thermal reservoir. We analyzed both for delta-correlated functions (white noise) and situations associated with Ornstein-Uhlenbeck processes (OUP) in colored noise. The effects of thermal reservoir and intramolecular coupling generate an effective transversal relaxation time. In the case of white noise, the resulting optical Bloch equations can be solved algebraically, unlike colored noise cases that requires numerical techniques.
In Ecuador, most collections of Drosophila use fruit-baited traps to study fruit flies, and for this reason little is known about the ecology of flower-breeding and feeding Drosophila species. However, some Ecuadorian species from the followings species groups: Drosophila flavopilosa Frey, 1919, Drosophila bromeliae Sturtevant, 1921, Drosophila onychophora Vilela & Bächli, 1990 and Drosophila morelia Vilela, 2004 have been found living in flowers of the botanical families Solanaceae, Bromeliaceae and Asteraceae (Silva and Martins 2004, Vilela and Bachli 2004, Figuero and Rafael 2011, Figuero et al. 2012, Robe et al.2014).
In this paper, the authors analyse and study some recent publications about integral inequalities related to generalized convex functions of several variables and the use of extended fractional integrals. In particular, they establish a new Hermite–Hadamard inequality for generalized coordinate φ-convex functions via an extension of the Riemann–Liouville fractional integral. Furthermore, an interesting identity for functions with two variables is obtained, and with the use of it, some new extensions of trapezium-type inequalities using Raina’s special function via generalized coordinate φ-convex functions are developed. Various special cases have been studied. At the end, a brief conclusion is given as well.
En el siglo XVIII Scopoli, Linné y Fabricio comenzaron a describir especies de Drosophilidae (Mateus et al., 2006). Desde entonces el número de géneros dentro de la familia se han incrementado a 73 (Brake & Bächli, 2008). La mayoría de estos géneros se encuentran en las regiones tropicales del mundo, y en la región Neotropical el género Drosophila está altamente diversifi cado con numerosas especies aún por descubrirse (De Medeiros & Klaczcko, 2004). Este género es el más abundante con aproximadamente 1.146 especies descritas (Brake & Bächli, 2008) y comprende alrededor del 53% del total de especies de la familia (Mateus et al., 2006).
Glacierised catchments are remote and hostile environments, in which streams from different water sources (e.g., glacier melt, rain/snowmelt, groundwater) converge, creating a complex mosaic of stream sites with varying levels of glacial influence and environmental conditions. This environmental heterogeneity, in turn, influences the assemblage and composition of aquatic communities and produces complex patterns of species diversity at the catchment scale. Objectives: In this contribution, we assessed biodiversity and community composition of aquatic macroinvertebrate communities from 51 stream site types in a glacierised catchment in the tropical Andes. The aim of our study was to: (1) determine diversity, rarity, commonness and spatial distribution patterns of aquatic macroinvertebrate communities from sites with different water sources, and (2) identify which environmental variables influence the density and presence of macroinvertebrate taxa and, in particular, of the subfamilies of the ubiquitous chironomids. Methods: Our study sites were grouped according to their water source and to their percentage of glacier coverage in the catchment (GCC). At each site we sampled aquatic macroinvertebrates, measured environmental variables and assessed community differences and environmental influence with ordination analyses and generalized linear models.
Esta revisión se enfoca en los conceptos básicos y fundamentos sobre los procesos fotocatalíticos, se consideró al TiO2 para describir los factores que determinan las reacciones fotocatalíticas. Se aborda el mecanismo de fotoexcitación de acuerdo con el modelo de bandas y se utiliza la termodinámica para establecer las diferencias entre la catálisis y la fotocatálisis. Se revisan y discuten las principales estrategias de síntesis y modificación del TiO2 que conllevan a una mayor eficiencia de las reacciones fotocatalíticas; se consideran además las aplicaciones de la fotocatálisis y su importancia en la remediación ambiental.
We consider a version of the ultimatum game which simultaneously combines reactive and Darwinian aspects with offers in [0,1]. By reactive aspects, we consider the effects that lead the player to change their offer given the previous result. On the other hand, Darwinian aspects correspond to copying a better strategy according to best game payoff when the current player compares with one of their neighbours. Therefore, we consider three different strategies, which govern how the players change their offers: greedy, moderate, and conservative. First, we provide an analytic study of a static version of game, where Darwinian aspects are not considered. Then, by using numerical simulations of a detailed and complete multi-agent system on a two-dimensional lattice, we add an extra feature, in which players probabilistically escape from extreme offers (those close to 0 or 1) for obvious reasons. The players are also endowed reciprocity on their gains as proposers, which is reflected on their gains as responders. We also analyse the influence of the player’s mobility effects. An analysis of the emergence of coexistence of strategies and changes on the dominant strategies are observed, which in turn depends on the player’s mobility rate.
Extensive seasonal migrations by humpback whales (Megaptera novaeangliae) have been well documented for decades (Kellogg, 1929; Dawbin, 1966; Clapham & Mead, 1999). Unlike other more oceanic whales with complex seasonal patterns, such as blue (Balaenoptera musculus), sei (B. borealis), and even Bryde’s (B. edeni) whales (Jefferson et al., 2015), the presence of humpback whales in destination areas in high and low latitudes are predominantly regular and predictable. Based on their breeding areas, the International Whaling Commission (IWC) recognizes seven different stocks of humpback whales in the Southern Hemisphere, assigned as Breeding Stocks A to G (IWC, 1998). Genetic studies largely support this separation, although a certain level of gene flow between the different stocks exists (Olavarría et al., 2007; Rosenbaum et al., 2017).
Aim: Small geographic ranges make species especially prone to extinction from anthropogenic disturbances or natural stochastic events. We assemble and analyse a comprehensive dataset of all the world's lizard species and identify the species with the smallest ranges—those known only from their type localities. We compare them to wide-ranging species to infer whether specific geographic regions or biological traits predispose species to have small ranges. Location: Global. Methods: We extensively surveyed museum collections, the primary literature and our own field records to identify all the species of lizards with a maximum linear geographic extent of <10 km. We compared their biogeography, key biological traits and threat status to those of all other lizards. Results: One in seven lizards (927 of the 6,568 currently recognized species) are known only from their type localities. These include 213 species known only from a single specimen. Compared to more wide-ranging taxa, they mostly inhabit relatively inaccessible regions at lower, mostly tropical, latitudes. Surprisingly, we found that burrowing lifestyle is a relatively unimportant driver of small range size. Geckos are especially prone to having tiny ranges, and skinks dominate lists of such species not seen for over 50 years, as well as of species known only from their holotype.
In this paper the concept of φ−convex stochastic process is introduced and certain algebraic properties are deduced. Also, some mean square integral inequalities of Hermite-Hadamard type are established. In addition, various mean square integral inequalities are investigated to find upper estimates using of the weighted arithmetic mean, the weighted power mean of order p and the logarithmic mean.
In this work the concept of exponentially (h1, h2)-convex function is introduced and using it, the Hermite-Hadamard inequality and some bounds for the right side of this inequality, via Raina's fractional integral operator and generalized convex functions, are established ..
Anolis biporcatus is a large green anole found in southern Mexico, Central America and northern South America. We examined morphological, molecular, and ecological aspects of specimens from localities throughout the range of A. biporcatus and found evidence that warrants elevating A. biporcatus parvauritus to species status. A. parvauritus differs from A. biporcatus in its dewlap colour pattern, overall morphology, and mitochondrial DNA. A deep mitochondrial split exists between northern and central Costa Rican samples of A. biporcatus, and substantial morphological variation occurs within this form. These patterns suggest potential species-level splits within currently recognized A. biporcatus. More extensive sampling of DNA data is needed to evaluate potential species boundaries within A. biporcatus.
Background: Understanding local anopheline vector species and their bionomic traits, as well as related human factors, can help combat gaps in protection. Methods: In San José de Chamanga, Esmeraldas, at the Ecuadorian Pacific coast, anopheline mosquitoes were sampled by both human landing collections (HLCs) and indoor-resting aspirations (IAs) and identified using both morphological and molecular methods. Human behaviour observations (HBOs) (including temporal location and bed net use) were documented during HLCs as well as through community surveys to determine exposure to mosquito bites. A cross-sectional evaluation of Plasmodium falciparum and Plasmodium vivax infections was conducted alongside a malaria questionnaire. Results: Among 222 anopheline specimens captured, based on molecular analysis, 218 were Nyssorhynchus albimanus, 3 Anopheles calderoni (n = 3), and one remains unidentified. Anopheline mean human-biting rate (HBR) outdoors was (13.69), and indoors (3.38) (p = 0.006). No anophelines were documented resting on walls during IAs. HBO-adjusted human landing rates suggested that the highest risk of being bitten was outdoors between 18.00 and 20.00 h. Human behaviour-adjusted biting rates suggest that overall, long-lasting insecticidal bed nets (LLINs) only protected against 13.2% of exposure to bites, with 86.8% of exposure during the night spent outside of bed net protection. The malaria survey found 2/398 individuals positive for asymptomatic P. falciparum infections. The questionnaire reported high (73.4%) bed net use, with low knowledge of malaria. Conclusion: The exophagic feeding of anopheline vectors in San Jose de Chamanga, when analysed in conjunction with human behaviour, indicates a clear gap in protection even with high LLIN coverage. The lack of indoor-resting anophelines suggests that indoor residual spraying (IRS) may have limited effect. The presence of asymptomatic infections implies the presence of a human reservoir that may maintain transmission
The use of sexually selected characters in inter- and intra-sexual interactions has long been of interest to evolutionary biologists. Recently, a distinction between sexually selected traits as ornaments versus weapons has been advanced. We investigated the behaviour of an enigmatic lizard with a prominent sexually dimorphic trait in an effort to describe whether the trait was the product of sexual selection and further whether it functioned as a weapon or an ornament. The subject of our study was the Ecuadorian proboscis anole (Anolis proboscis), a slow-moving cryptic species endemic to the north-western slopes of the Andes in Ecuador. Males, but not females, of this species bear a rostral appendage that has been described as an exaggerated trait resulting from sexual selection. However, a thorough description of the use of the rostral appendage in social interactions is lacking. Here, we describe social interactions of this species during 11 male–female courtships and mating interactions, as well as three male–male agonistic interactions. We describe four types of displays by males, many involving the rostral appendage. We found that the rostral appendage is used as an ornament in social displays but not as a weapon in combat. We also show that, unlike other lizards with rostral appendages, male A. proboscis hatch with this structure already developed.
Ecuador is one of the most reptile-diverse countries in the world, with 464 currently recognized species. Similar to other taxa, reptiles in Ecuador face important conservation challenges because of anthropogenic activities. Using distribution data of nearly 90% of the species of reptiles from continental Ecuador, as well as information on ecosystem protection status and anthropogenic activities, we present the first comprehensive quantitative study of reptile conservation in Ecuador. While species richness is higher in northwestern Ecuador and the central-northern Amazon, the conservation priority areas identified in this study also include the central Pacific coast, southwestern Ecuador, and the central-southern Amazon. Similar areas have been identified by previous studies as conservation gaps. Thus, our study reinforces the idea of protecting those areas to improve the conservation of biodiversity in continental Ecuador.
Mauritia flexuosa dominated palm swamps are an important forest resource covering over 30,000 km across the Amazon basin. In Ecuadorean Amazonia, Mauritia flexuosa, a dioecious and arborescent palm species, forms small and isolated populations or large and dense stands on poorly drained soils. How these populations are genetically interconnected and how genetic diversity varies between cohorts of different ages remains little studied although they are important for conservation of these ecosystems. The genetic structure of Mauritia flexuosa was studied in five natural stands using eight microsatellite loci and two cohorts (seedling and adults). In addition, age structure and sex ratio within the stands were assessed using transects. The age structure of the studied Mauritia flexuosa stands is represented by a high number of seedlings (mean = 1,153.6/ha) and adults (mean = 563.2/ha), with a sex ratio favoring female individuals (1.42:1). These stands are also characterized by a fine-scale genetic structure, high observed heterozygosity (mean: H =0.52; H =0.52), high inbreeding (mean: F = 0.26; F = 0.26), low number of migrants (N =0.29), strong genetic differentiation (mean: pairwise R / D-values = 0.08/ 0.74; mean R /D-values = 0.17/ 0.76), and an average effective population size (N ) of 191.42 individuals. No intergenerational genetic variation was detected between seedlings and adults. We suggest that the high genetic diversity and inbreeding as well as the strong differentiation among stands of these populations could be explained, at least partially, by a low genetic connectivity among populations. Destructive harvesting of its fruits and defaunation will be major threats to Mauritia flexuosa populations in the future. Abstract in Spanish is available with online material.
The distributions of amphibians, birds and mammals have underpinned global and local conservation priorities, and have been fundamental to our understanding of the determinants of global biodiversity. In contrast, the global distributions of reptiles, representing a third of terrestrial vertebrate diversity, have been unavailable. This prevented the incorporation of reptiles into conservation planning and biased our understanding of the underlying processes governing global vertebrate biodiversity. Here, we present and analyse the global distribution of 10,064 reptile species (99% of extant terrestrial species). We show that richness patterns of the other three tetrapod classes are good spatial surrogates for species richness of all reptiles combined and of snakes, but characterize diversity patterns of lizards and turtles poorly. Hotspots of total and endemic lizard richness overlap very little with those of other taxa. Moreover, existing protected areas, sites of biodiversity significance and global conservation schemes represent birds and mammals better than reptiles. We show that additional conservation actions are needed to effectively protect reptiles, particularly lizards and turtles. Adding reptile knowledge to a global complementarity conservation priority scheme identifies many locations that consequently become important. Notably, investing resources in some of the world’s arid, grassland and savannah habitats might be necessary to represent all terrestrial vertebrates efficiently.
Most dyes used in the textile industry are chemically stable and poorly biodegradable, therefore, they are persistent in the environment and difficult to degrade by conventional methods. An alternative treatment for this kind of substance is heterogeneous photocatalysis using TiO2, so, in this work, it is proposed to degrade Direct Blue 1 (DB1) using microparticulate TiO2 irradiated with e-beam at three different doses: 5, 10 and 20 kGy (J/kg). The DB1 degradation was implemented in a batch reactor (DB1 initial concentration = 50 mg L−1, pH 2.5, TiO2 concentration = 200 mg L−1). We have demonstrated that the photocatalytic power of TiO2, when irradiated with e-beam (5, 10, 20 kGy), varies slightly, with minor effects on photodegradation performance. However, the dose of 10 kGy showed a slightly better result, according to the DB1 photodegradation rate constant. Adsorption process was not affected by irradiation; its isotherm was fitted to Freundlich’s mathematical model. The DB1 photodegradation rate constants, after one hour of treatment, were: 0.0661 and 0.0742 min−1 for irradiated (10 kGy) and nonirradiated TiO2, respectively. The degradation rate constant has an increase of 12.3% for irradiated TiO2. Finally, there was no evidence of mineralization in the degradation process after 60 min of treatment. According to the results, the irradiation of microparticulate TiO2 with e-beam (10 kGy) slightly improves the photodegradation rate constant of DB1.
Neotropical monkey lizards (Polychrus) are arboreal lizards with compressed bodies, partially fused eyelids and strikingly long, whip-like tails. The eight currently recognized species occur in the lowlands of South and Central America. Based on the largest taxon and character sampling to date, we analyze three mitochondrial and one nuclear gene using Bayesian methods to (1) infer the phylogeny of Polychrus under both concatenated-tree and speciestree methods; (2) identify lineages that could represent putative undescribed species; and (3) estimate divergence times. Our species tree places P. acutirostris as the sister taxon to all other species of Polychrus. While the phylogenetic position of P. gutturosus and P. peruvianus is poorly resolved, P. marmoratus and P. femoralis are strongly supported as sister to P. liogaster and P. jacquelinae, respectively. Recognition of P. auduboni and P. marmoratus sensu stricto as distinct species indicates that the populations of "P. marmoratus" from the Amazon and the Atlantic coast in Brazil represent separate species. Similarly, populations of P. femoralis from the Tumbes region might belong to a cryptic undescribed species. Relative divergence times and published age estimates suggest that the orogeny of the Andes did not play a significant role in the early evolution of Polychrus.
We provide notes on the natural history and images of the immature stages of six butterfly species inhabiting west Ecuadorian dry forest, including Magneuptychia libye, Memphis artacaena, Scada zemira, Opsiphanes cassina fabricii, Heliconius erato cyrbia and Dryas iulia moderata (Lepidoptera: Nymphalidae). Five of these species have no previously published life history information from this region and habitat, and one species is an endemic. We report two new generic host plant records, Hieronyma (Euphorbiaceae) for Memphis, and Piresia (Poaceae) for Magneuptychia. Eggs or caterpillars of all species were collected in primary forest and reared to adult in the laboratory. The study was carried out in the Bosque Seco Lalo Loor Reserve located in western Ecuador, from June through August 2013, and was part of a capacity-building program to train local people in butterfly research, which included collection and rearing components.
Climate change is altering forest dynamics in the tropics, with large potential impacts on forest structure and understory conditions. However, we found that canopy height distribution and openness remained stable over two decades in the western Amazon, and that gap creation rates would need to increase 300% before affecting equilibrium. Abstract in Spanish is available with online material
El objetivo de este estudio fue sintetizar nanopartículas de plata con métodos de química verde, combinando extractos de plantas. En la primera etapa se sintetizaron nanopartículas de plata a partir de AgNO3 10 mM con un extracto acuoso de cilantro al 5 %. En la segunda etapa se colocó el látex de sangre de drago al 10 % en etanol-agua (1:1 v/v), como aditivo a la disolución acuosa de nanopartículas. Por espectrofotometría UV-Visible se comprobó la formación de nanopartículas de plata a 422 nm y 439 nm respectivamente. Para la caracterización se realizaron análisis por Espectrofotometría de Infrarrojos con transformadas de Fourier acoplada a un accesorio horizontal de reflectancia total atenuada (FTIR-HATR), Microscopía Electrónica de Barrido con detector de rayos X (SEM-EDX), Espectrofotometría de Absorción Atómica de Llama (FAAS) y Dispersión de Luz Dinámica (DLS). En los resultados obtenidos, se observaron cambios evidentes en las bandas de los espectros FTIR, al comparar las nanopartículas sintetizadas con el extracto de cilantro y mezcladas con el látex de sangre de drago. Se determinó el tamaño de nanopartícula a través de SEM, obteniendo un tamaño de nanopartícula de 50 y 72 nm en cada etapa. El análisis EDX mostró la presencia de plata en un 14,9 % durante la síntesis y únicamente un 0,6 % del elemento al adicionar el látex, lo cual sugiere un adecuado recubrimiento alrededor de las nanopartículas.
Five new species of Drosophila (Diptera, Drosophilidae) related with Araceae. Drosophila anthurium sp. nov., Drosophila tsachila sp. nov., Drosophila guajalito sp. nov., Drosophila deloscolorados sp. nov. and Drosophila cartucho sp. nov. were captured in inflorescences of the family Araceae between 1800 and 2200 m of altitude in the Scientific Station Rio Guajalito, province of Santo Domingo de los Tsáchilas, Ecuador. The new species present surstylus and aedeagus elongated, and aedeagal apodeme very short. Analysis of external morphology and male terminalia indicate that the five new species do not belong to any of the Drosophila groups associated with flowers.
Cóndor and eastern Andean slopes in the province of Zamora Chinchipe, southeastern of Ecuador. We inferred its phylogenetic position using DNA sequences of mitochondrial and nuclear genes. The new species is strongly supported as part of a clade that includes P. ardalonychus, P. cajamarcensis, P. ceuthospilus, P. chalceus, P. minutulus, P. luteolateralis, P. parvillus, P. ockendeni, P. unistrigatus, and P. walkeri. It can be distinguished from all other species from Cordillera del Cóndor and congeneric species by the unique combination of the following characters: (1) iris light blue with black reticulations; (2) skin of dorsum finely shagreen with scattered pustular tubercles and absence of dorsal folds; (3) tympanic membrane and tympanic annulus visible; (4) snout rounded in dorsal and lateral view; (5) upper eyelid bearing two or three enlarged subconical tubercles; (6) cranial crest absent; (7) males lacking vocal sac and slits; and (8) venter uniformly bright red, light red, salmon or orange. The new species is most closely related to P. ardalonychus, P. cajamarcensis, P. ceuthospilus, P. ockendeni and P. unistrigatus. We consider the new species to be Endangered following IUCN criteria because it has been severely affected by large scale open-pit mining in some localities. Currently, the amphibian fauna of the Cordillera del Cóndor and nearby protected areas are threatened by large–scale copper and gold mining projects with devastating effects on ~20 species, including several undescribed ones.
Ecological interactions play a fundamental role in determining the genetic structure of plant species in time and space. The demography of the Andean Puya hamata has been linked to fire regimes and hummingbird behaviour, which might modify the plant’s population genetic structure. Naturally, poor dispersal results in patches of genetically related plants, a pattern intensified further by burning which promotes seedling germination around parent plants. Later, when these plants flower, large patches are attractive to territorial hummingbirds which prevent visits by traplining hummingbird species, carrying pollen from likely unrelated plants. To explore this hypothesis, a genetic study of P. hamata using microsatellite markers was conducted with (i) isolated and grouped adults in two size categories of patches, and (ii) seeds collected from the same patches and isolated individuals. Isolated individual plants presented a higher observed heterozygosity with close to zero inbreeding. Adult plants from large patches showed a lower observed heterozygosity and higher inbreeding than plants from other spatial contexts. Seed genetic structure displayed a gradient of diversity: lower at patch centres but higher at patch edges, in small patches, and for isolated infructescences. The spatial context of these plants, especially the contrast between large patch centres and other situations, determines the genetic diversity of their seeds via hummingbird foraging behaviour. Territorial hummingbirds restrict gene flow in and out of large patches, but traplining hummingbirds maintain genetic diversity among isolated plants, small patches, and plants at the edges of large patches. Our study illustrates the need to consider interactions between land use, plants, and their pollinators when considering genetic diversity at the landscape scale
1. The extent to which historical dispersal, environmental features and geographical barriers shape the phylogenetic structure and turnover of tree communities in northwestern Amazonia at multiple spatial scales remains poorly understood. 2. We used 85 floristically standardized 0.1-ha plots (DBH ≥ 2.5 cm) distributed in three subregions of northwestern (NW) Amazonia across three main habitat types (floodplain, swamp and terra firme forests) to hypothesize that (a) historical dispersal overcome geographical barriers, which meant low local phylogenetic relatedness and low phylogenetic turnover. (b) Geographical barriers triggered dispersal limitation, causing high local and subregional phylogenetic clustering and high regional phylogenetic turnover. (c) Edaphic properties and flooding were negatively associated with stem size and determined the tree phylogenetic structure and turnover at local and regional scales in Amazon forests. 3. We found that the extent to which environmental or evolutionary features shaped the phylogenetic structure and phylogenetic similarity of tree communities in NW Amazonia was scale dependent. Specifically, we show that the relative importance of environmental factors increases as spatial scale and species pool decreases. Furthermore, we find that these results are generally robust for both adult and juvenile trees. 4. Synthesis. Our analysis at the regional (NW Amazon) scale lends support to the idea of Amazonian forests as a large meta-community primarily structured by historical dispersal at large spatial scales with an increasing importance of environmental factors at finer spatial scales. The convergence of ancestral lineages across habitat types may have been due to the relatively recent formation of geographical barriers that promoted local isolation and allopatric speciation.
Chemical elements, which are present in drinking water, could vary due to water sources, treatment processes or even the plumbing materials. Most of these elements do not represent a threat, while others, such as heavy metals, have been proven to cause harmful effects over human and aquatic wildlife. In this study, the quality of drinking water in three cities in Ecuador, Quito, Ibarra and Guayaquil was assessed through a multielement analysis and the heavy metal pollution index (HPI). A total of 102 drinking water samples and six natural water samples were collected and analyzed. Within the scope of analysis, results show that water quality complies with local and international guidelines. HPI did not show significant differences in the water that is supplied to the different neighborhoods of the three cities studied. However, actions should be taken to protect the sources of water, especially in Guayaquil, due to the presence of lead and chromium. For instance, lead was found in 2.8% of the samples in concentrations above World Health Organization (WHO) recommended values. Thus, we suggest to assessing the quality and age of the plumbing system within the whole country, in order to avoid drinking water contamination with heavy metals
El rastreo de anticuerpos anti-eritrocitarios es una de las pruebas pretransfusionales más importantes en medicina transfusional por su aporte en la prevención de reacciones adversas luego de la administración de hemocomponentes. Sin embargo, no todos los bancos de sangre ecuatorianos han incluido esta prueba en sus protocolos de trabajo. Para demostrar su importancia se realizó el presente estudio cuyo propósito fue alertar al sistema nacional de salud sobre la existencia de aloinmunización en la población de donantes de sangre. Se estableció una prevalencia de anticuerpos anti-eritrocitarios del 0,27% y se identificó una mayor frecuencia en el género femenino. Los anticuerpos identificados estuvieron relacionados con los sistemas eritrocitarios Rh (RH), Kell (KEL), Duffy (FY) y Kidd (JK). Una de las limitaciones para la inclusión de esta prueba en los bancos de sangre y servicios de medicina transfusional es el elevado costo de los reactivos y la falta de paneles de células eritrocitarias de composición homocigota y heterocigota para la identificación de anticuerpos anti eritrocitarios nativos, situación que constituye una oportunidad para que el Ministerio de Salud Pública del Ecuador promueva mejores estrategias para la importación de reactivos, reducción de costos y disponibilidad de paneles de células.
En este documento, se reporta el efecto del residuo de caucho, recuperado de la pista de aterrizaje producto de la fricción del neumático y superficie de rodamiento, como material modificador de una mezcla asfáltica que utiliza asfalto AC-20. Se estudió, el comportamiento de la mezcla asfáltica resultante cuando el residuo se agrega como reemplazo de una porción de agregado fino. La mezcla modificada se conformó mediante el proceso vía seca. Los especímenes de mezcla asfáltica fueron analizados por el método Marshall. Los resultados experimentales muestran que la incorporación del residuo a la mezcla asfáltica, mejora sus propiedades volumétricas tales como vacíos de aire, vacíos en el agregado mineral y los vacíos llenos de asfalto; los primeros se redujeron y los dos últimos aumentaron en relación a la mezcla sin modificar. Por otro lado, la estabilidad aumentó y el flujo mantuvo valores dispuestos en la norma. El ensayo de módulo de rigidez, que determinó el comportamiento del pavimento en sitio, igualmente aumentó, lo que demuestra significativamente las ventajas de usar este residuo de caucho en la mezcla asfáltica.
Se reporta la caracterización de una mezcla asfáltica, modificada con desechos especiales proveniente de baterías de automóviles. La modificación se realizó por vía seca y se evaluó la relación de vacíos que caracteriza la calidad de una mezcla asfáltica, en el material modificado y sin modificar. El estudio se realizó añadiendo en peso porcentajes de 5%, 15%, 25% y 35% de escoria a la mezcla asfáltica. Los resultados obtenidos de la integración de desechos especiales a la mezcla, indican que dicha modificación mejora sus propiedades mecánicas y el rendimiento de los materiales al momento de ser usados en la mezcla. En comparación con la mezcla sin modificar, la muestra modificada presentó un aumento de un 30% en estabilidad y un 8% en flujo, lo que predice una mejora en las propiedades mecánicas de la mezcla en cuanto a aumento en resistencia. Por otro lado, las propiedades volumétricas de la mezcla modificada se mantuvieron en el rango dispuesto en la norma y el ensayo de módulo de rigidez, que determinó el comportamiento del pavimento en sitio, igualmente aumentó. Lo que demuestra las ventajas de modificar la mezcla asfáltica con la escoria de baterías desechadas.
En el presente artículo se expone una formalización del problema de clasificación de conjuntos y una esquematización para su resolución. Se aborda el caso ´ de estudio de la Clasificación de la ecuación cuadrática en dos variables para ejemplificar el procedimiento propuesto. Con esto, se plantea un acercamiento didáctico a la metodología planteada para la clasificación de conjuntos, el cual puede ser utilizado por parte de los docentes de los primeros años de educación superior en sus ´ alumnos.
Magnolia napoensis , a new species from the Amazonian lowlands of Ecuador and Peru is described and illustrated. This species belongs to subsection Talauma; it is similar to M. rimachii in leaf shape but differs from the latter in being taller with a larger diameter and having fewer lateral leaf veins, more numerous hypsophylls, larger flowers, longer outer petals, more numerous stamens and fruits ovoid and ribbed vs. subglobose and smooth. The new species differs from M. neillii by its leaves with fewer lateral veins, glabrous petioles and terminal internodes, more numerous hypsophylls, fewer stamens and ovoid fruits of smaller size, with fewer carpels. Magnolia napoensis is assessed as endangered (EN B2ab(iii) in accordance with the IUCN criteria.
The Hyloscirtus larinopygion group is a clade of 16 species of large hylids that inhabit cascading Andean streams. They have brown coloration that, in most species, contrasts with bright marks. Herein morphological and genetic evidence is used to describe a new species of the group from Cordillera del Cóndor, a sub-Andean mountain chain that has phytogeographic affinities with the Guianan Tepuis. The new species is characterized by dark-brown coloration with contrasting bright orange flecks and by the presence of an enlarged and curved prepollex protruding as a spine. The new species is closely related to H. tapichalaca and an undescribed species from the southern Andes of Ecuador. The genetic distance between H. hillisi sp. n. and its closest relative, H. tapichalaca, is 2.9% (gene 16S mtDNA). Our phylogeny and a review of recently published phylogenies show that amphibians from Cordillera del Cóndor have close relationships with either Andean or Amazonian species. Amphibians do not show the Condor-Guianan Tepuis biogeographic link that has been documented in plants
El trabajo interdisciplinario de ciencias como criminalística de campo, medicina legal, biología forense, entomología forense, permiten lograr una investigación técnico-científica más objetiva y eficaz al momento de analizar un hecho delictivo. El presente trabajo se enfoca en la labor de la entomología forense en la investigación de un proceso judicial abarcando sus técnicas de actuación, manejo de muestras entomológicas (e.g., colección, preservación y almacenaje), y normas jurídicas del Ecuador en las que el personal encargado debe regirse para que las evidencias sean auténticas, legales y científicamente válidas. Es por ello que el presente estudio, expone los principales lineamientos del análisis de muestras entomológicas para una correcta labor forense.
The genus Dendropsophus is one of the most speciose among Neotropical anurans and its number of described species is increasing. Herein, molecular, morphological, and bioacoustic evidence are combined to assess species limits within D. parviceps, a widely distributed species in the Amazon Basin. Phylogenetic relationships were assessed using 3040 bp sequences of mitochondrial DNA, genes 12S, ND1, and CO1. The phylogeny shows three wellsupported clades. Bioacoustic and morphological divergence is congruent with those clades demonstrating that Dendropsophus parviceps is a species complex. Dendropsophus parviceps sensu stricto occurs in the Amazon basin of Ecuador, northern Peru, southern Colombia and northwestern Brazil. It is sister to two previously undescribed species, D. kubricki sp. n. from central Peru and D. kamagarini sp. n. from southern Peru, northeastern Bolivia, and northwestern Brazil. Genetic distances (uncorrected p, gene 12S) between D. parviceps and the new species is 3 to 4%. Dendropsophus kamagarini sp. n. can be distinguished from D. parviceps by having a prominent conical tubercle on the distal edge of the upper eyelid (tubercle absent in D. parviceps). Dendropsophus kubricki sp. n. differs from D. parviceps by having scattered low tubercles on the upper eyelids (smooth in D. parviceps). Dendropsophus parviceps and both new species differ from all their congeners by their small size (adult maximum SVL = 28.39 mm in females, 22.73 mm in males) and by having a bright orange blotch on the hidden areas of the shanks and under arms.
Nowadays, the increasing pollution of natural water effluents with herbicides, such as atrazine (ATZ, 2-chloro-4- ethylamino-6-isopropylamino-s-triazine), is an emerging problem that has not received the sufficient attention. This work presents a study on ATZ degradation under an electrochemical advanced oxidation process (EAOP), such as anodic oxidation (AO). The degradation of 175 mL of 10 and 40 mg L ATZ solutions was studied using Pt or BDD as anode. The assays were made with a stirred tank cell, using a supporting electrolyte of 0.050 mM of Na SO at pH 3.0 by applying 0.18, 0.27 and 0.37 A cm . The degradation rate increased by increasing current density, regardless of the anode employed. Greater amounts of ATZ were removed at higher organic load. The pesticide decay always obeyed a pseudo-first-order kinetics. A high degradation efficiency of 97%-99% was obtained by the more powerful AO-BDD process at 0.37 A cm . High performance liquid chromatography (HPLC) was used to follow the evolution of major oxidation products by AO-BDD, such as desethyl atrazine, desethyl desisopropyl atrazine and cyanuric acid.
Amphibians are probably the most vulnerable group to climate change and climate change associate diseases. This ongoing biodiversity crisis makes it thus imperative to improve the taxonomy of anurans in biodiverse but understudied areas such as Amazonia. In this study, we applied robust integrative taxonomic methods combining genetic (mitochondrial 16S, 12S and COI genes), morphological and environmental data to delimit species of the genus Amazophrynella (Anura: Bufonidae) sampled from throughout their pan-Amazonian distribution. Our study confirms the hypothesis that the species diversity of the genus is grossly underestimated. Our analyses suggest the existence of eighteen linages of which seven are nominal species, three Deep Conspecific Lineages, one Unconfirmed Candidate Species, three Uncategorized Lineages, and four Confirmed Candidate Species and described herein. We also propose a phylogenetic hypothesis for the genus and discuss its implications for historical biogeography of this Amazonian group.
The capacity of 133 fungal endophyte isolates for degrading petroleum hydrocarbons was evaluated. The endophytes were isolated from leaf and stem tissues from 23 plants collected in a natural habitat contaminated with crude oil in southwestern Ecuador. Their capacity for hydrocarbon biodegradation was tested by an in vitro colorimetric qualitative test during 10 days, using the Minimal Salt Medium and crude oil as the carbon source. Taxonomic identification of the endophytic fungi that showed bioactivity in the qualitative test was carried out by analysis of the ITS gene of the region 18S of the rDNA. Endophytes showed the best results in the previous qualitative test where selected for a quantitative in vitro test for 30 days. Residual hydrocarbons were tracked by infrared spectroscopy (IR) and gas chromatography (GC) with a flame ionization detector. The maximum removal rates of total petroleum hydrocarbons were 99.6% (IR) and 99.8% (GC), corresponding to fungi of the genus Verticillium sp. and Xylaria sp. 1 respectively. This is the first report of biodegradation of crude oil hydrocarbons by endophytic fungi in a tropical ecosystem. The results suggest these fungal isolates are potential hydrocarbon biodegraders that could be used in bioremediation processes.
Analysis of genetic polymorphism is a powerful tool for epidemiological surveillance and research. Powerful inference from pathogen genetic variation, however, is often restrained by limited access to representative target DNA, especially in the study of obligate parasitic species for which ex vivo culture is resource-intensive or bias-prone. Modern sequence capture methods enable pathogen genetic variation to be analyzed directly from host/vector material but are often too complex and expensive for resource-poor settings where infectious diseases prevail. This study proposes a simple, cost-effective genome-wide locus sequence typing’ (GLST) tool based on massive parallel amplification of information hotspots throughout the target pathogen genome. The multiplexed polymerase chain reaction amplifies hundreds of different, user-defined genetic targets in a single reaction tube, and subsequent agarose gel-based clean-up and barcoding completes library preparation at under 4 USD per sample. Our study generates a flexible GLST primer panel design workflow for Trypanosoma cruzi, the parasitic agent of Chagas disease. We successfully apply our 203-target GLST panel to direct, culture-free metagenomic extracts from triatomine vectors containing a minimum of 3.69 pg/μl T. cruzi DNA and further elaborate on method performance by sequencing GLST libraries from T. cruzi reference clones representing discrete typing units (DTUs) TcI, TcIII, TcIV, TcV and TcVI. The 780 SNP sites we identify in the sample set repeatably distinguish parasites infecting sympatric vectors and detect correlations between genetic and geographic distances at regional (< 150 km) as well as continental scales. The markers also clearly separate TcI, TcIII, TcIV and TcV + TcVI and appear to distinguish multiclonal infections within TcI. We discuss the advantages, limitations and prospects of our method across a spectrum of epidemiological research.
As geographic range estimates for the IUCN Red List guide conservation actions, accuracy and ecological realism are crucial. IUCN’s extent of occurrence (EOO) is the general region including the species’ range, while area of occupancy (AOO) is the subset of EOO occupied by the species. Data-poor species with incomplete sampling present particular difficulties, but species distribution models (SDMs) can be used to predict suitable areas. Nevertheless, SDMs typically employ abiotic variables (i.e., climate) and do not explicitly account for bioticinteractions that can impose range constraints. We sought to improve range estimates for data- poor, parapatric species by masking out areas under inferred competitive exclusion. We did so for two South American spiny pocket mice: Heteromys australis (Least Concern) and Heteromys teleus (Vulnerable due to especially poor sampling), whose ranges appear restricted by competition. For both species, we estimated EOO using SDMs and AOO with four approaches: occupied grid cells, abiotic SDM prediction, and this prediction masked by approximations of the areas occupied by each species’ congener. We made the masks using support vector machines (SVMs) fit with two data types: occurrence coordinates alone; and coordinates along with SDM predictions of suitability. Given the uncertainty in calculating AOO for low-data species, we made estimates for the lower and upper bounds for AOO, but only make recommendations for H. teleusas its full known range was considered. The SVM approaches (especially the second one) had lower classification error and made more ecologically realistic delineations of the contact zone.For H. teleus, the lower AOO bound (a strongly biased underestimate) corresponded to Endangered (occupied grid cells), while the upper bounds (other approaches) led to Near Threatened. As we currently lack data to determine the species’ true occupancy within the post-processed SDM prediction, we recommend that an updated listing for H. teleus include these bounds for AOO. This study advances methods for estimating the upper bound of AOO and highlights the need for better ways to produce unbiased estimates of lower bounds. More generally, the SVM approaches for post-processing SDM predictions hold promise for improving range estimates for other uses in biogeography and conservation.
Fungal samples were collected in the Sangay (SP) and Llanganates (LP) National Parks in Ecuador. Sequences of the internal transcribed spacer regions (ITS1-5.8S ITS2) of the ribosomal DNA of the samples were analyzed. Taxonomic identification of fungi of the order Xylariales was done through phylogenetic analysis using a Maximun Likelihood method. All analyzed collections presented here belong to the genus Xylaria, of these eight belong to PL and two to SP. Four sample were not identified at the species level, suggesting it could be a new species. This data contributes with base information on the biodiversity of the Parks, necessary to design and implement measures for the conservation of fungi in Ecuador.
Novel species of fungi described in this study include those from various countries as follows: Angola, Gnomoniopsis angolensis and Pseudopithomyces angolensis on unknown host plants. Australia, Dothiora corym biae on Corymbia citriodora, Neoeucasphaeria eucalypti (incl. Neoeucasphaeria gen. nov.) on Eucalyptus sp., Fumagopsis stellae on Eucalyptus sp., Fusculina eucalyptorum (incl. Fusculinaceae fam. nov.) on Eucalyptus socialis, Harknessia corymbiicola on Corymbia maculata, Neocelosporium eucalypti (incl. Neocelosporium gen. nov., Neocelosporiaceae fam. nov. and Neocelosporiales ord. nov.) on Eucalyptus cyanophylla, Neophaeomoniella corymbiae on Corymbia citriodora, Neophaeomoniella eucalyptigena on Eucalyptus pilularis, Pseudoplagiostoma corymbiicola on Corymbia citriodora, Teratosphaeria gracilis on Eucalyptus gracilis, Zasmidium corymbiae on Corymbia citriodora. Brazil, Calonectria hemileiae on pustules of Hemileia vastatrix formed on leaves of Coffea arabica, Calvatia caatinguensis on soil, Cercospora solanibetacei on Solanum betaceum, Clathrus natalensis on soil, Diaporthe poincianellae on Poincianella pyramidalis, Geastrum piquiriunense on soil, Geosmithia carolliae on wing of Carollia perspicillata, Henningsia resupinata on wood, Penicillium guaibinense from soil, Periconia caespitosa from leaf litter, Pseudocercospora styracina on Styrax sp., Simplicillium filiforme as endophyte from Citrullus lanatus, Thozetella pindobacuensis on leaf litter, Xenosonderhenia coussapoae on Coussapoa floccosa. Canary Islands (Spain), Orbilia amarilla on Euphorbia canariensis. Cape Verde Islands, Xylodon jacobaeus on Eucalyptus camaldulensis. Chile, Colletotrichum arboricola on Fuchsia magellanica. Costa Rica, Lasiosphaeria miniovina on tree branch. Ecuador, Ganoderma chocoense on tree trunk. France, Neofitzroyomyces nerii (incl. Neofitzroyomyces gen. nov.) on Nerium oleander.
Bordetella pertussis is the causative agent of pertussis, which mainly affects unvaccinated children, while Bordetella parapertussis causes a disease presenting clinical characteristics that are indistinguishable from whooping cough. Despite high vaccination coverage, pertussis remains a public health concern worldwide, with approximately 140 000 cases reported annually. Here we determined the prevalence of B. pertussis and B. parapertussis infection among infants under one year of age by polymerase chain reaction (PCR); our aim being to identify whether the data obtained relates to the relevant sociodemographic and clinical data. The study included 86 samples of nasopharyngeal swabs from infants aged between 0---12 months, who were reported as probable cases of whooping cough by the health centers around the Ecuadorian highlands, from August 2016 to July 2017. The nasopharyngeal swabs were cultured and microbiological and molecular analyses were performed. B. pertussis was identified by PCR in 41% of the samples (30/86), more than half of which corresponded to infants aged between 0---3 months. Moreover, a statistically significant correlation (p < 0.05) between the identification of bacteria in culture and the catarrhal stage of the disease was observed. The results obtained from the study highlighted the need for an active national surveillance of pertussis,in particular for laboratory testing, to provide a highly sensitive and more specific diagnosis of Bordetella infection.
Leptodeira is one of the most widespread and taxonomically problematic snake taxa in the Americas. Here we describe a new species of Leptodeira from the Andes of southern Ecuador based on morphological and molecular data. The new species is geographically close and morphologically similar to L. ornata and L. larcorum, from which it can be distinguished by having smaller dorsal body blotches, a longer tail, and shorter spines on the hemipenial body. The shortest genetic distances between the new species and its congeners are 0.02 (16S), 0.05 (cytb), and 0.18 (ND4). The new species is restricted to the Jubones River Basin in southern Ecuador, an area of endemism for other reptile species. Our phylogenetic analysis based on mitochondrial and nuclear DNA sequence data also supports recognition of the names L. larcorum (restricted to Peru) for “L. septentrionalis larcorum”, and L. ornata for populations of “L. s. ornata” from central and eastern Panama, western Colombia, and western Ecuador. However, some samples of “L. s. ornata” from Panama and Costa Rica, as well as the new species described herein, are not included within or more closely related to L. ornata, which is sister to the clade (L. bakeri, L. ashmeadii
Inga kursarii is a new species collected in the terra firme forests of the northwestern Amazon, one of the regions with the highest tree species diversity in the world. According to morphological and phylogenetic analyses, the new species is morphologically similar and sister to Inga gracilifolia Ducke, but it can be distinguished by having 5–6 pairs of caducous leaflets, elliptical leaflets with acute apex and slightly asymmetrical base, spiked inflorescence, subsessile flowers, calyx tube with 4 lobes, tufts of hairs at the apex of calyx lobes, corolla tube with non-reflexed lobes, shorter staminal tubes, and capitate stigma. In addition, analyses of the chemical defensive profile (chemocoding) show that both taxa are chemically different, with I. kursarii having a chemistry based on gallocatechin/epigallocatechin gallates, and I. gracilifolia producing a series of dihydroflavonols. Finally, we present a table with a comparison of diagnostic characters that allows separation of the two species.
Se evaluó la composición y estructura florística de dos remanentes de Bosque Andino Montano Alto, localizados en la cima del volcán Ilaló (3 190 m). Estos pertenecen a las Comunas de San Francisco de Baños-La Merced y Tola Chica. En cada remanente se establecieron 10 cuadrantes de 10×10 m (0,2 ha); se censaron todos los individuos con un DAP ≥ 2,5 cm. Un total de 533 individuos fueron registrados y clasificados en 20 familias y 40 especies. Se observó una dominancia de Oreopanax ecuadorensis (38,3 % en el remanente 1 y 42,6 % en el remanente 2), seguido de Vallea stipularis y Geissanthus pichinchae para ambos. La misma relación aparecieron en los valores más altos de área basal, donde Oreopanax ecuadorensis registró 0,85 y 0,62 m2 ; de igual forma con un IVI entre 17 % y 19 %. Los índices, alfa de Fisher, Shannon y Simpson, usados para medir la diversidad alfa, no reflejaron diferencias significativas para la conformación vegetal de los cuadrantes. Asimismo, los análisis de NMMDS y ANOSIM empleados para medir la diversidad beta no revelaron diferencias significativas entre ambos; lo que sugirió una composición vegetal continua histórica. Estudios similares son importantes para conocer, entender y conservar la vegetación remanente en los Andes ecuatorianos.
We report the evaluation of a hot asphalt mixture, conventionally used in the streets of Ecuador, modified with plastic polypropylene lids in order to improve their mechanical characteristics. The mixture has been modified using crushed waste from plastic bottle caps in an aggregate size equivalent to that retained in sieve number 8, which according to the ASTM standard is 2.36 millimeters. Marshall stability and flow tests were carried out on specimens fabricated with different percentages of polypropylene waste. It has been shown that the addition of polypropylene taps results in the improved Marshall properties. The results indicate that a modified asphalt mix has useful characteristics for a good performance as asphalt mixtures for paving.
El propósito de la investigación es determinar el perfil de los hogares ecuatorianos; respecto a los hábitos y sus prácticas ambientales. Se utilizó la base de datos de la encuesta nacional Prácticas Ambientales en los Hogares, realizada por el INEC el 2015. Se efectuó el análisis estadístico descriptivo, análisis factorial de correspondencias y análisis jerárquico para definir las clases de hogares. Las variables que describen los ejes factoriales son: área de ubicación, clasificación de los residuos, forma de eliminar los residuos, hábitos e instalaciones para ahorro del agua. Los principales resultados son: el 59.2% de hogares no clasifica los residuos. El 33.1% de hogares depositaron los desechos electrónicos/ eléctricos con el resto de basura, el 47.5% eliminó el aceite y/o grasas de cocina con el resto de basura y el 69.6% eliminó los focos ahorradores con el resto de basura. El 76.3% de hogares cierran las llaves mientras jabonan los platos, se bañan y se cepillan los dientes. Solo el 7.7% de hogares disponen de economizadores de chorro, el 4% disponen de inodoro doble descarga y el 3% colocan una botella de agua u otro objeto dentro del tanque. El primer grupo jerárquico (36.93% de hogares) es el más representativo, cuyo perfil es: hogares del área urbana, no clasifican los residuos porque no hay contenedores específicos o centros de acopio para reciclables, depositan con el resto de basura aceites y grasas de cocina y focos ahorradores.
Polycyclic aromatic hydrocarbons (PAHs) are a group of more than 100 different chemical substances, which contain two, or more fused aromatic rings most of them toxic or carcinogenic. In this study, the Quechers extraction conditions were adapted to perform the extraction of aqueous samples. Quechers has become a standard technique for the analysis of pesticides and other organic substances. Its simplicity and low cost have made it popular in laboratories around the world for processing samples such as fruits and vegetables. The success of this method on solid samples contrasts with the advances in the extraction of aqueous samples where tedious steps of extraction, concentration and solvent changes must be carried out prior to the instrumental analysis. A methodology for the liquid-liquid extraction (water/acetonitrile) of 15 PAHs in aqueous matrices was developed. The mixture was saturated with anhydrous sodium sulfate to cause the partitioning and the extract was analyzed by High-Resolution Liquid Chromatography with Fluorescence Detection (HPLC-FLD). The recoveries of analytes achieved (61-114%) were comparable to those expected using traditional extraction techniques, and with moderate uncertainty. The results were consistent with the expectations for of the required analytical and concentration ranges.
Los materiales refractarios son de gran importancia para la humanidad, debido a su capacidad de resistencia altas temperaturas. Son empleados en la industria del cemento, cerámica, vidrio, metalúrgica, siderúrgica y petroquímica. El alcalde es el que los materiales refractarios son sometidos a varios mecanismos de desgaste durante el proceso de producción, cuentos como: ataque químico, mecánico, termomecánico y carga térmica. Si el material no cuenta con las propiedades adecuadas, su durabilidad se ve afectada, y por ende los costos de producción. En este sentido, la combinación de los nanomateriales, se convierte en una alternativa importante para mejorar las propiedades de los materiales refractarios, proporcionándoles mejor densidad, baja porosidad, resistencia a la erosión, baja conducta térmica, entre otros. El artículo presente realiza una revisión de varios trabajos de investigación, acerca de la evolución de los nanomateriales aplicados a los materiales refractarios, entre los que se mencionan el uso de grafeno, dióxido de titanio, óxido férrico, magnesia, zirconia, alúmina y sílice, para mejorar las propiedades físicas de los materiales refractarios. De manera general, los estudios demuestran que el uso de los nanomateriales, demuestra un desabastecimiento de los materiales refractarios mejores propiedades, en rangos de concentración específicos. Sin embargo, todos los estudios han sido realizados a nivel de laboratorio, por lo que sería promisorio su uso a nivel industrial.
La alerta por la pandemia causada por el coronavirus SARS-CoV-2 ha desatado una carrera contra el tiempo por búsqueda de un posible tratamiento. Varios fármacos antivirales empleados para controlar el desarrollo de la enfermedad, son derivados de moléculas obtenidas de plantas, sin embargo, su aislamiento puede resultar en la disminución o anulación del efecto. El uso de plantas ancestrales en países en vías de desarrollo, donde el acceso a un tratamiento farmacológico específico aún es limitado, las terapias naturales representan la primera línea de defensa frente al virus. En el presente estudio, se analizaron varias investigaciones respecto a la actividad in vitro de plantas sudamericanas con potencial actividad antiviral, clasificadas por países (Argentina, Brasil, Bolivia, Chile, Colombia, Ecuador, Paraguay, Perú, Uruguay y Venezuela). La familia Asteraceae presentó el mayor porcentaje de uso para el tratamiento de enfermedades respiratorias con un 18 %. Se concluye que la biodiversidad de plantas sudamericanas puede ser aprovechada, por lo que se sugiere realizar un estudio in vitro sobre el virus SARS-CoV-2.
Desde tiempos muy remotos, las plantas y los aceites esenciales extraídos de ellos han cumplido un papel muy importante en el área terapéutica gracias a sus propiedades biológicas, como la acción larvicida, analgésica, antinflamatoria, antioxidante, fungicida entre otros. Se ha comprobado que los aceites esenciales exhiben la actividad biológica, lo que es extremadamente importante en el campo de la ciencia y la industria. Por esta razón en las últimas décadas ha ido tomando la alcaldía importancia el estudio y desarrollo de técnicas analíticas que permitan la determinación e identificación de la composición química de los aceites esenciales ya que son una alternativa potencial a los compuestos sintéticos, debido a la resistencia que estos mismos han desarrollado frente a microorganismos patógenos. En este artículo se hace un análisis de la composición química de los aceites esenciales de algunas especies que pertenecen a las familias: Lamiaceas, Asteraceas y Vervenaceas y la relación con su actividad Biológica. Se concluye que la actividad antimicrobiana de los aceites esenciales depende de su composición química y de la cantidad de los componentes individuales.
Las reacciones de transferencia de electrones de las biomoléculas son un foco importante de investigación extensa en Química, Física y Bioquímica. La electroquímica proporciona potentes herramientas para estudiar los procesos de transferencia de electrones en sistemas bioquímicos, donde las enzimas son moléculas de particular interés. Entre los nanomateriales para la inmovilización enzimática en superficies de electrodos, las nanopartículas de oro son una buena alternativa para sus propiedades: biocompatibilidad, altas propiedades electroactivas, fuerte capacidad de adsorción, relación superficie-volumen y alta actividad catalítica. El peróxido de hidrógeno (H2O2), un sustrato para la enzima "Peroxidasa rábano picante", desempeña un papel crítico en campos industriales, biológicos, farmacéuticos y muchos otros. El nivel de concentración de H2O2 es un parámetro biológico significativo en el estudio de enfermedades como la enfermedad de Alzheimer, infarto de miocardio, enfermedad de Parkinson, Cáncer, etc. Por lo tanto, es de gran importancia desarrollar métodos eficientes para la detección sensible y selectiva de H2O2 en condiciones fisiológicas. En el presente manuscrito, se revisa el uso de nanopartículas de oro en electrodos modificados enzimáticos (biosensores) para la determinación de H2O2. Los resultados más relevantes indican que las nanopartículas de oro favorecen la transferencia directa de electrones entre la proteína redox y el electrodo. Las nanopartículas de oro proporcionan un entorno natural para la inmovilización biomolecular que permite una mayor estabilidad y vida útil en el electrodo.
Se presenta una revisión de estudios sobre usos de los residuos lignocelulósicos en la industria del papel, combustible, como precursor de otros compuestos químicos y la experiencia en la optimización de materiales filtrantes. Se establecen materiales que han sido estudiados con este fin y los análisis fisicoquímicos que se han realizado como parte de la caracterización. Además, se revisó el potencial de materiales filtrantes aptos para ser usados como filtros, en los cuales se probó su desempeño en lixiviado de suelos bajo condiciones controladas, potencial como combustible, tecnologías de membranas, bioadsorbente de cromo (III), remoción de plomo y níquel con restos de cereales y cítricos, remoción de plomo con residuos de palma
Los recubrimientos comestibles para frutas y verduras han logrado prolongar la vida útil de los alimentos postcosecha, dichos recubrimientos a base polisacáridos o proteínas, que incorporan en su formulación lípidos y plastificantes, sirven de barrera para intercambio gaseoso, protegen a los alimentos debido a sus propiedades mecánicas, reducen pérdidas nutricionales y organolépticas, no alteran la composición fisicoquímica y adicionan protección antimicrobiana. Actualmente, los recubrimientos comestibles están formados a base de compuestos bifásicos o trifásicos combinados en una matriz polimérica que potencializan, funcionalizan o adicionan nuevas propiedades al recubrimiento, que vinculado al uso de la nanotecnología en la industria alimentaria han permitido obtener nuevos recubrimientos comestibles, incorporando a la matriz polimérica compuestos antimicrobianos, antioxidantes y con potencial bioactivo. Adicionalmente, el uso de métodos de homogenización como microfluidización y ultrasonicación permiten obtener nanoemulsiones con tamaño de gota nanométrica y uniformes, brindando al recubrimiento nuevas características que en conjunto con el uso del electrospinning (electrohilado), como método físico de aplicación del recubrimiento, se puede obtener nanofibras con alto potencial para el control microbiológico, organoléptico y nutricional, aplicable para la conservación de frutas y verduras. Este artículo revisa el uso de algunas innovaciones en recubrimientos comestibles con material nanoestructurado para la conservación de frutas y verduras
Mercury (Hg) contamination is a problem that currently affects not only the environment but also human health. Various types of commercial adsorbents have been proposed for its removal. Silver is a noble element that can chemically adsorb mercury, forming amalgams. However, its use as an adsorbent presents the following disadvantages: rapid surface saturation and high cost. These limitations can easily be overcome using silver nanoparticles (AgNPs). With a size of less than 100 nm, their reactivity, their high surface area, and a minimal amount of metallic precursor, they are ideal candidates for mercury removal. This study presents a compendium of the use of conventional mercury adsorbents and the use of AgNPs for their colorimetric detection and removal in different matrices, in both the aqueous and gas phases of Hg0 and Hg2+ .In addition, the number of patents available in each case is analyzed. AgNPs as colorimetric sensors allow for quick detection of mercury in-situ. Additionally, the adsorption systems formed with AgNPs, allow for the obtaining of stable and chemically inert complexes, facilitating their recycling. It is concluded that the use of AgNPs is particularly efficient for the detection and removal of mercury, presenting a removal percentage of over 90%. As a result of the patents analyzed, its use is perfectly applicable at an industrial level.
En el presente artículo, se expone una generalización del conjunto ternario de Cantor basada en la beta-expansión de un número; además, se presenta que, bajo hipótesis adecuadas, esta extensión también corresponde a la manera constructiva de la definición del conjunto ternario de Cantor. Finalmente, se demuestra que los conjuntos que se obtienen son, en efecto, conjuntos de Cantor.
En el presente artículo se establecen ciertos resultados de importancia para el análisis matemático, específicamente relacionados con las derivadas conformables de orden fraccional, entre ellos se destacan: la regla de la cadena, el Teorema del valor medio de Cauchy y la Regla de L’Hopital. Se espera que estos resultados estimulen la investigación en esta ́area
We consider the Four-Wave mixing (FWM) signal and the effects of the pump beam on the nonlinear optical responses of a two-level system where intramolecular coupling is modelled by two coupled harmonic electronic potentials, displaced both in their equilibrium minimum position and energy. We investigate the modifications introduced in the FWM signal , considering a simple representation for the vibrational structure and including molecular electronic states with nonzero permanent dipole moments. The critical quantities for this analysis are the transition and permanent dipole moments, which depend strongly on the intramolecular coupling. Our results show how both absorption and dispersion are affected by the vibronic coupling .
Glyphosate [N-(phosphonomethyl)-glycine] is a herbicide with several commercial formulations that are used generally in agriculture for the control of various weeds. It is the most used pesticide in the world and comprises multiple constituents (coadjutants, salts, and others) that help to effectively reach the action’s mechanism in plants. Due to its extensive and inadequate use, this herbicide has been frequently detected in water, principally in surface and groundwater nearest to agricultural areas. Its presence in the aquatic environment poses chronic and remote hazards to human health and the environment. Therefore, it becomes necessary to develop treatment processes to remediate aquatic environments polluted with glyphosate, its metabolites, and/or coadjutants. This review is focused on conventional and non-conventional water treatment processes developed for water polluted with glyphosate herbicide; it describes the fundamental mechanism of water treatment processes and their applications are summarized. It addressed biological processes (bacterial and fungi degradation), physicochemical processes (adsorption, membrane filtration), advanced oxidation processes—AOPs (photocatalysis, electrochemical oxidation, photo-electrocatalysis, among others) and combined water treatment processes. Finally, the main operating parameters and the effectiveness of treatment processes are analyzed, ending with an analysis of the challenges in this field of research
Proponemos modificaciones de las ecuaciones de Bloch ópticas convencionales para un sistema molecular, cuando consideramos los efectos de acoplamiento intramolecular. Modelamos la molécula aislada como curvas de energía de Born-Oppenheimer que consisten en dos estados electrónicos cruzados descritos como potenciales armónicos, con los mínimos desplazados en coordenadas nucleares y energía. Consideramos dos estados vibracionales y una perturbación, que puede surgir de una correlación residual electrón-electrón y/o términos de acoplamiento spin-órbita en el Hamiltoniano del sistema, causando la separación de las dos curvas según la regla del cruce evitado. Las ecuaciones extendidas de Bloch ópticas permiten establecer la dinámica de un sistema molecular de estados adiabáticos sujeto a la interacción de un reservorio térmico e interactuando con campos electromagnéticos. En las ecuaciones se observa que haciendo nulo el factor de acoplamiento intramolecular, se recuperan las ecuaciones de Bloch ópticas convencionales para un sistema molecular con potenciales armónicos cuyos mínimos se encuentran exactamente en la misma coordenada nuclear sujeto a la aproximación Born-Oppenheimer.
Se reporta una correlación analítica-técnica entre ensayos de laboratorio de Módulo Resiliente y California Bearing Ratio, para un agregado que proviene de la mina de Copeto (Toachi – Santo Domingo de Los Tsáchilas-Ecuador), la cual arroja valores reales útiles en la optimización del material utilizado en proyectos viales, a través de la obtención del Módulo Resiliente. El estudio se sustenta en la cualificación de la mina, mediante ensayos fisicoquímicos, que permite conocer las características propias de los agregados, según las normas ASTM. Con el logro de una correlación entre el CBR y el Módulo Resiliente real de la mina en estudio, se tiene valores reales en el comportamiento de los materiales, que se van a usar en la estructura de la vía, lo que genera como resultado espesores de capas menores, que, al momento de la construcción reduce el tiempo de entrega, la cantidad de material y por consiguiente el costo final de la construcción de la vía.
We describe through integrative taxonomy a new Amazonian species of leaf-litter toad of the Rhinella margaritifera species group. The new species inhabits open lowland forest in southwest Amazonia in Brazil, Peru, and Bolivia. It is closely related to a Bolivian species tentatively identified as Rhinella cf. paraguayensis. Both the new species and R. paraguayensis share an uncommon breeding strategy among their Amazonian congeners: each breeds in moderate to large rivers instead of small streams or ponds formed by rainwater. The new species is easily differentiated from other members of the R. margaritifera species group by having a strongly developed bony protrusion at the angle of the jaw, a snout–vent length of 63.4–84.7 mm in females and 56.3–72.3 mm in males, well-developed supratympanic crests with the proximal portion shorter than the parotoid gland in lateral view, a divided distal subarticular tubercle on finger III, and multinoted calls composed of groups of 7–9 pulsed notes and a dominant frequency of 1,012–1,163 Hz. Recent studies have shown that the upper Madeira Basin harbors a megadiverse fauna of anurans, including several candidate species. This is the first member of the R. margaritifera species group to be described from this region in recent years, and at least two additional unnamed species await formal description.
Se presenta un nuevo reporte de Werneria (Asteraceae) para Ecuador, es W. spathulata, una pequeña hierba rizomatosa encontrada en los páramos del volcán Antisana. Además, se documenta el redescubrimiento de Xenophyllum acerosum en el Ecuador después de su primera colección hace 73 años en la provincia de Azuay. Se proveen fotografías del hábito de las dos especies, así como del hábitat donde fueron halladas.
La malaria es una enfermedad que afecta a las zonas tropicales del mundo, siendo un importante problema de salud pública. En los últimos 18 años la incidencia en Ecuador ha disminuido, lo que lo ubicó entre los países con capacidad de eliminar la malaria hasta el 2020. Sin embargo, a partir del 2015 se ha presentado un incremento en el número de casos afectando principalmente a la población más vulnerable de las áreas fronterizas del país. La presencia de infecciones asintomáticas, las infecciones sub microscópicas y asintomáticas constituyen un problema para la eliminación de la enfermedad. En este trabajo se estudió la epidemiología de la malaria en las comunidades del norte de la provincia de Esmeraldas, fronterizas con Colombia, con muestras sanguíneas del 2017 y se aplicó una encuesta epidemiológica de conocimientos, actitudes y prácticas de malaria (CAP) a los jefes de familia. La prevalencia total de malaria en las zonas de estudio obtenida mediante técnicas moleculares fue de 5.83%. Todas las infecciones fueron asintomáticas. La población encuestada presentó un conocimiento básico respecto a la malaria, pero la falta de prácticas para prevenir la malaria es un factor importante que podría dificultar la eliminación de la malaria. Este estudio proporciona información sobre el estado de la malaria en las comunidades de estudio del norte de Esmeraldas que facilitará a la formulación de nuevas estrategias para el control y prevención de la enfermedad.
La identificación inequívoca del antígeno D en medicina transfusional es de vital importancia para evitar reacciones postransfusionales y la enfermedad hemolítica del recién nacido. Es común el uso de reactivos serológicos monoclonales o tarjetas de gel y su interpretación está definida por cruces, de acuerdo con la reacción serológica. El propósito de este estudio fue determinar la frecuencia del factor Rh y las variantes del antígeno D en una población afroecuatoriana. Se trató de un estudio descriptivo, transversal con muestreo aleatorio simple de 541 pobladores. Para la tipificación del factor Rh se utilizó la metodología en tubo con antisueros monoclonales y para la detección de las variantes de D se utilizaron tarjetas de gel ID- Coombs Anti-IgG. Las lecturas se verificaron mediante el análisis del índice kappa. Se aplicó estadística descriptiva y el análisis de Chi cuadrado para establecer la relación de las variables y su significación. Se identificó una frecuencia del 92% de individuos Rh(D) positivo y un 8% Rh(D) negativo. El 4,80% de los individuos presentaban la variante D débil y el 79% reacciones serológicas entre 2 y 3(+) indicativas de otras variantes del antígeno D. El fenotipo más común fue el R0/R0. Estos datos demuestran la necesidad de confirmar la existencia de variantes del antígeno D en esta población para un mejor manejo de la sangre. Una limitante constituye la disponibilidad de técnicas moleculares para la genotipificación de D; sin embargo, se podría implementar la fenotipificación RHCE como estrategia pretransfusional.
We describe two new species of salamanders of the genus Oedipina, subgenus Oe dopinola, from two localities on the northwestern foothills of Ecuador, at elevations between 921 and 1,067 m. These are the southernmost members of the genus. We examined different museum collections and we found just three specimens of Oedipina from Ecuador, obtained throughout the history of herpetological collections in the country.We identify two of the three specimens as new species, but refrain from assigning a specific identity to the third, pending further study. Oedipina villamizariorum sp. n. is a medium-sized member of the genus, with a narrow, relatively pointed head and blunt snout; dorsolaterally oriented eyes, moderate in size; and digits that are moderately long and having pointed tips. Oedipina ecuatoriana sp. n., somewhat larger, has a narrow head and broadly rounded snout; this new species differs from all known Oedipina by the distinctive presence of paired prefrontal bones and a reduced phalangeal formula: 0-0-1-0; 0-1-2-1-1. We provide detailed descriptions of the osteology of both new species.Finally, we present a phylogenetic hypothesis for the genus, including one of the two new species, based on partial sequences of mitochondrial DNA.