Repositorio Digital Ikiam (Univ. Regional Amazónica)
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A new method for microplastic sampling and isolation in mountain glaciers: A case study of one antisana glacier, Ecuadorian Andes
Get PDFMicroplastic contamination has become ubiquitous in terrestrial and marine environments. Recent studies have shown that the wind can transport and deposit microplastics in high mountain ecosystems, but microplastic contamination therein is unknown. Because mountain glaciers are the primary source of drinking water for large urban areas in the Andes, assessing recent and historical microplastic contamination is crucial. Surface snow can indicate recent microplastic deposition, whereas glacial ice cores can provide information on historical contamination. At mountain glaciers, the inhospitable conditions and the difficult accessibility are limiting factors for sampling. Therefore, sampling and laboratory analytical methods have to be integrated and planned ensuring replicability. Here, we present 1) a new methodology to identify sampling areas within the accumulation zone of a glacier to obtain samples of surface snow and ice cores; 2) a less-manipulative analytical technique for the preparation and isolation of microplastics derived from glaciers. In addition, we identified the minimum amount of sample necessary to obtain robust data on contamination by microplastics
Genomic and Fitness Consequences of Genetic Rescue in Wild Populations
Get PDFGene flow is an enigmatic evolutionary force because it can limit adaptation but may also rescue small populations from inbreeding depression [1, 2, 3]. Several iconic examples of genetic rescue—increased population growth caused by gene flow [4, 5]—have reversed population declines [6, 7]. However, concerns about outbreeding depression and maladaptive gene flow limit the use of human-mediated gene flow in conservation [8, 9]. Rescue effects of immigration through demographic and/or genetic mechanisms have received theoretical and empirical support, but studies that monitor initial and long-term effects of gene flow on individuals and populations in the wild are lacking. Here, we used individual-based mark-recapture, multigenerational pedigrees, and genomics to test the demographic and evolutionary consequences of manipulating gene flow in two isolated, wild Trinidadian guppy populations. Recipient and source populations originated from environments with different predation, flow, and resource regimes [10]. We documented 10-fold increases in population size following gene flow and found that, on average, hybrids lived longer and reproduced more than residents and immigrants. Despite overall genomic homogenization, alleles potentially associated with local adaptation were not entirely swamped by gene flow. Our results suggest that genetic rescue was caused not just by increasing individual genetic diversity, rather new genomic variation from immigrants combined with alleles from the recipient population resulted in highly fit hybrids and subsequent increases in population size. Contrary to the classic view of maladaptive gene flow, our study reveals conditions under which immigration can produce long-term fitness benefits in small populations without entirely swamping adaptive variation
Desarrollo de una librería estadística en R para el manejo de datos de cromatografía gaseosa bidimensional
Get PDFComprehensive two-dimensional gas chromatography (GC×GC) offers detailed chemical information about volatile and semivolatile analytes from complex samples. However, the high complexity of the data structure encourages the development of new tools for a more efficient data handling and analysis. Although some tools have already been presented to overcome this challenge, there is still need for improvement. In this manuscript, we present a toolbox containing a pipeline for end-to-end basic GC×GC data processing which can be used for both, signal pre-processing and multivariate data analysis. The pre-processing algorithms perform signal smoothing, baseline correction, and peak alignment, while the multivariate analysis is done through Multiway Principal Component Analysis (MPCA). The software is capable to prepare the chromatographic data for further applications with other chemometric tools, e.g.: cluster analysis, regression, discriminant analysis, etc. The performance of this new software was tested on in-house experimental dataset and on two other published datasets
Aplicación de una estrategia didáctica para la enseñanza de las integrales indefinidas y definidas en las carreras de ingeniería
Get PDFLa enseñanza de la matemática requiere ser sustenta en la aplicación de
estrategia de enseñanza aprendizaje que contribuyan a una mejor comprensión
de sus teorías, por ello este trabajo parte de la necesidad de ejemplificar la
aplicación de una estrategia didáctica para la enseñanza del Cálculo
Infinitesimal en las carreras de ingeniería. La estrategia se sostiene en un
modelo centrado en la sistematización formativa en cálculo infinitesimal es
expresión de la relación entre la dimensión analítica infinitesimal del Cálculo
para ingenieros y dimensión sistematización contextualizada de recursos del
Cálculo Infinitesimal. La estrategia parte del Nivel de Esencialidad dado en
objetivos formativos de la Facultad de Ciencias de la Tierra y Agua, de la
Universidad Regional Amazónica Ikiam, se valora el Nivel Estratégico con la
determinación del estado actual y el estado deseado, así como el entorno donde
se desarrolla el proceso de formación en Cálculo Infinitesimal. El Nivel de Concreción, se ejemplifica a través del tema “Cálculo Integral de funciones
reales de una variable real”. Este nivel para el Cálculo infinitesimal en las
carreras de ingeniería tiene dos subprocesos: subproceso de formación analítica
infinitesimal y subproceso de sistematización contextualizada. Ambos
subprocesos cuentan con objetivos específicos, orientaciones pedagógicas y
acciones; así como ejemplos y ejercicios de integrales indefinidas y definidas
orientados a lograr una sistematización teórica y práctica de estos objetos
matemáticos que surgen de la necesidad del cálculo de magnitudes físicas.
Finalmente, se evalúa la efectividad de la estrategia formativa
Flood Hazard Assessment in Data-Scarce WatershedsUsing Model Coupling, Event Sampling,and Survey Data
Get PDFThe application of hydrologic and hydrodynamic models in flash flood hazard assessment is mainly limited by the availability of robust monitoring systems and long-term hydro-meteorological observations. Nevertheless, several studies have demonstrated that coupled modeling approaches based on event sampling (short-term observations) may cope with the lack of observed input data. This study evaluated the use of storm events and flood-survey reports to develop and validate a modeling framework for flash flood hazard assessment in data-scarce watersheds. Specifically, we coupled the hydrologic modeling system (HEC-HMS) and the Nays2Dflood hydrodynamic solver to simulate the system response to several storm events including one, equivalent in magnitude to a 500-year event, that flooded the City of Tena (Ecuador) on 2 September, 2017. Results from the coupled approach showed satisfactory model performance in simulating streamflow and water depths (0.40 ≤ Nash-Sutcliffe coefficient ≤ 0.95; −3.67% ≤ Percent Bias ≤ 23.4%) in six of the eight evaluated events, and a good agreement between simulated and surveyed flooded areas (Fit Index = 0.8) after the 500-year storm. The proposed methodology can be used by modelers and decision-makers for flood impact assessment in data-scarce watersheds and as a starting point for the establishment of flood forecasting systems to lessen the impacts of flood events at the local scale
Ultrafiltración de agua superficial de un sistema fluvial urbano: Análisis de comunidades bacterianas y virales asociadas.
Get PDFLos principales impulsores de la aparición de enfermedades virales y bacterianas son los
cambios socioeconómicos, demográficos y ambientales. La ciudad de Tena posee una
población de alrededor de 25.000 personas, las mismas que se estima que liberen 70 L
de agua de agua residual por día. Este vertido continuo, provoca el aumento de las
concentraciones de sólidos y nutrientes en los sistemas fluviales; causando una
perturbación en las comunidades bacterianas y virales e implicaciones en la salud del
ecosistema de agua dulce. La ultrafiltración (UF) ha surgido como una alternativa de bajo
consumo para la remoción de agentes contaminantes provocados por el continuo
vertido de agua residual. La presente investigación tiene como objetivo identificar los
mecanismos de bloqueo de poro de membrana relacionado con el depósito de materia
orgánica y compuestos biológicos (bacterias y virus) utilizando membranas con
diferente corte de peso molecular (100, 30 y 10 kDa). Se realizó una caracterización
fisicoquímica y microbiológica del agua superficial del río, antes y después de la UF para
evaluar la eficiencia de remoción de contaminantes. Los resultados indican que el
sistema de UF resulta eficiente como un proceso de potabilización secundario para agua
superficial altamente contaminada empleando membranas con menor CPM (80% de
remoción). Además, se produjo la formación de la torta con una estructura fractal
tridimensional la misma, que acumuló contaminantes fisicoquímicos y biomasa
bacteriana y viral. En este análisis se muestra la formación de biofouling que alberga
microorganismos indicadores de contaminación fecal los cuáles son de gran importancia
ecológica y de calidad higiénica del agua
Tissue accumulation and the effects of long-term dietary copper contamination on osmoregulation in the mudflat fiddler crab Minuca rapax (Crustacea, Ocypodidae)
Get PDFWe examined copper accumulation in the hemolymph, gills and hepatopancreas, and hemolymph osmolality, Na+
and Cl−
concentrations, together with gill Na+/
K+-ATPase and carbonic anhydrase activities, after dietary copper delivery (0, 100
or 500 Cu μg g−1) for 12 days in a fiddler crab, Minuca rapax. In contaminated crabs, copper concentration decreased in the
hemolymph and hepatopancreas, but increased in the gills. Hemolymph osmolality and gill Na+/
K+-ATPase activity increased
while hemolymph [
Na+] and [
Cl−] and gill carbonic anhydrase activity decreased. Excretion likely accounts for the decreased
hemolymph and hepatopancreas copper titers. Dietary copper clearly affected osmoregulatory ability and hemolymph Na+
and
Cl−
regulation in M. rapax. Gill copper accumulation decreased carbonic anhydrase activity, suggesting that dietary copper
affects acid–base balance. Elevated gill Na+/
K+-ATPase activity appears to compensate for the ion-regulatory disturbance.
These effects of dietary copper illustrate likely impacts on semi-terrestrial species that feed on metal-contaminated sediments
The gastromyzophorous tadpoles of Atelopus elegans and A. palmatus (Anura: Bufonidae), with comments on oral and suction structures
Get PDFThe tadpoles of the Neotropical genusAtelopusare only known for 26 out of 96 speciesdescribed. Here, we describe the tadpoles ofA. elegansandA. palmatusincluding ontogeneticinformation, measurements, and images of individuals in several stages of growth. Both speciesare compared with their congeners taking into account some relevant features such as thecoloration and relative measurements. Our description focuses on the abdominal sucker andmouth by providing scanning electron microscopy images and comparing the suctorialmechanism with other groups of anurans andfish. We also provide an update to knowledgeof the abdominal suckers, and information about their lateral line system and the distributionof their lateral line openings. The results show that brown marks over a tan surface and anirregular distribution of marks along the body and tail are unique toA. elegans; whilea patterned distribution of contrasting marks, and the presence of submarginal papillae areunique toA. palmatus. Also, both species show differences in the structures of their teeth.Finally, we conclude that some characters such as coloration, presence or absence of somestructures, and relative measurements are useful for identifying the species.
(8) (PDF) The gastromyzophorous tadpoles of Atelopus elegans and A. palmatus (Anura: Bufonidae), with comments on oral and suction structures. Available from: https://www.researchgate.net/publication/338437945_The_gastromyzophorous_tadpoles_of_Atelopus_elegans_and_A_palmatus_Anura_Bufonidae_with_comments_on_oral_and_suction_structures [accessed Jan 21 2020]
Estructura poblacional, fenología reproductiva y productividad de Euterpe precatoria Mart. en un humedal amazónico ecuatoriano
Get PDFThe fruits of Euterpe precatoria are an important economic resource in Amazonian
countries such as Brazil, Bolivia and Colombia. In the Ecuadorian Amazonia, an area that
needs market alternatives for sustainable production, there is an underutilization of this
resource. In order to generate basic knowledge for the development of sustainable use and
management plans for the species, we studied the population structure, reproductive
phenology and fruit productivity, as well as their relationship with the climate and
microtopography. All individuals were registered in an area of 3300m2 within a 1-hectare
plot located in a swamp in Misahuallí, Napo. The phenology of 60 adult individuals was
monitored monthly, for two years. 17 infructescences were collected to quantify fruit
production. A raster microtopography model of the plot was made in relation to the
location of the individuals. The total density of individuals (1197 ind / ha) and adults (40
ind / ha) was lower compared to records from other countries. The population structure
showed a higher percentage of young individuals (69%) indicating that the development of
the population is stable. Synchronous peaks of flowering occurred annually between May
and September, and fruiting between October and April, correlated with the rainiest and
least rainy months of the year, respectively, contrary to most studies in other parts of the
Amazon. On average, there was a production of 3.1 infructescences per individual and an
average of 4310 (954 - 8140) fruits produced per fruit. The estimated production potential
per unit area was 907 ton / ha. These values exceed the majority of records in Brazil and
Bolivia. The microtopography of the swamp, in relation to flooding, suggests a higher
concentration of individuals in higher places within the plot, although this pattern does not
show influence on fruit productivity as has been seen in other studies. Our results will serve
as a baseline for authorities and communities interested in the management of this species
La gestión universitaria en la universidad territorial sustentable
Get PDFEl presente trabajo tiene como propósito caracterizar los procesos de gestión de
la Educación Superior y de la Universidad Territorial para que contribuya a la
sustentabilidad de esta. Es por ello que la gestión en la universidad se debe
edificar sobre estructuras que permitan integración vertical y horizontal de sus
misiones, Las que han de ser comprometidas, flexibles y trascendentes para
anticiparse a los cambios y que su liderazgo institucional, individual y colectivo,
sea innovador y visionario; orientado anticipadamente a las nuevas demandas
de la sociedad. Al mismo tiempo, un concepto de calidad de Educación Superior
para todos que implique desarrollar un ambiente cualitativo de trabajo en las
organizaciones educativas, mediante la institucionalización de las mejores
prácticas, tanto técnicas como administrativas, capaces de promover la
formación humana sostenible y la calidad de vida de estudiantes, profesores y
funcionarios técnico-administrativos. Por ello, es posible enfrentar el desafío y
desterrar los viejos mitos que aún persisten en los claustros universitarios.
Aspiraciones como calidad, excelencia, internacionalización, eficiencia y auto
evaluación, vinculación con el mundo del trabajo, descentralización, entre
otros, forman parte de un nuevo discurso universitario que se abre paso con firmeza. Por tal razón, se requiere de una mayor elaboración, en el orden
praxiológico, epistemológico y de la gestión, con propuestas que permitan ofrecer
una respuesta en las actuales y futuras condiciones cambiantes desde su entorno