COMPARACIÓN DE DOS TÉCNICAS DE CONCENTRACIÓN VIRAL A PARTIR DE AGUAS CRUDAS DEL DEPARTAMENTO NORTE DE SANTANDER

Los métodos de detección de virus entéricos a nivel de laboratorio presentan cierto nivel de complejidad, debido a que estos entes se encuentran muy diluidos en aguas.  Esto genera la necesidad de encontrar métodos eficientes que permitan concentrarlos de forma rápida, selectiva, sensible, eliminando interferencias presentes en la matriz y con la certeza de tener partículas virales infecciosas. En este estudio se comparó la ultrafiltración tangencial (UFT) y la separación inmunomagnética (IMS) como técnicas de concentración viral, empleando Rotavirus como modelo.  El grado de eficiencia de las mismas fue confirmado empleando la reacción en cadena de la polimerasa acoplada a una reverso-transcriptasa (RT-PCR) la cual facilitó la identificación de Rotavirus a partir de aguas crudas en cuatro plantas de potabilización del departamento Norte de Santander, incluyendo sus fuentes de abastecimiento. La UFT se llevó a cabo en un equipo dotado entre otros componentes de membranas millipore de 0.8, 0.45 and 0.22 µm. Para la IMS se emplearon micropartículas de 2.0 µm funcionalizadas con anticuerpos monoclonales anti-Rotavirus.  Los resultados permitieron determinar que tanto la IMS como la UFT concentraron eficientemente Rotavirus a partir de agua crudas.  No obstante, la IMS exhibió mayor sensibilidad a la hora de comparar la cantidad de RNA viral extraído a partir de cada muestra analizada. Además, está técnica sólo requirió 2 horas para obtener el concentrado viral en comparación de 24 horas empleadas por la UFT. Por tanto, se recomienda emplear para la concentración de virus patógenos presentes en aguas crudas la técnica de separación inmunomagnética.Palabras claves: Concentración, virus, agua cruda, filtración, partículas magnéticas

Evidence of suppression of onchocerciasis transmission in the Venezuelan Amazonian focus.

BACKGROUND: The World Health Organization (WHO) has set goals for onchocerciasis elimination in Latin America by 2015. Most of the six previously endemic countries are attaining this goal by implementing twice a year (and in some foci, quarterly) mass ivermectin (Mectizan®) distribution. Elimination of transmission has been verified in Colombia, Ecuador and Mexico. Challenges remain in the Amazonian focus straddling Venezuela and Brazil, where the disease affects the hard-to-reach Yanomami indigenous population. We provide evidence of suppression of Onchocerca volvulus transmission by Simulium guianense s.l. in 16 previously hyperendemic Yanomami communities in southern Venezuela after 15 years of 6-monthly and 5 years of 3-monthly mass ivermectin treatment. METHODS: Baseline and monitoring and evaluation parasitological, ophthalmological, entomological and serological surveys were conducted in selected sentinel and extra-sentinel communities of the focus throughout the implementation of the programme. RESULTS: From 2010 to 2012–2015, clinico-parasitological surveys indicate a substantial decrease in skin microfilarial prevalence and intensity of infection; accompanied by no evidence (or very low prevalence and intensity) of ocular microfilariae in the examined population. Of a total of 51,341 S. guianense flies tested by PCR none had L3 infection (heads only). Prevalence of infective flies and seasonal transmission potentials in 2012–2013 were, respectively, under 1 % and 20 L3/person/transmission season. Serology in children aged 1–10 years demonstrated that although 26 out of 396 (7 %) individuals still had Ov-16 antibodies, only 4/218 (2 %) seropositives were aged 1–5 years. CONCLUSIONS: We report evidence of recent transmission and morbidity suppression in some communities of the focus representing 75 % of the Yanomami population and 70 % of all known communities. We conclude that onchocerciasis transmission could be feasibly interrupted in the Venezuelan Amazonian focus. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/s13071-016-1313-z) contains supplementary material, which is available to authorized users

A low-absorption disk zone at low Galactic latitude in Centaurus

We investigate the properties of two stellar concentrations in a low-absorption disk zone in Centaurus, located respectively at $\ell=306.47^{\circ}$, $b=-0.61 ^{\circ}$, and $\ell=307.01^{\circ}$, $b=-0.74 ^{\circ}$. The present analysis is based mostly on 2MASS photometry, as well as optical photometry. Based on colour-magnitude diagrams and stellar radial density profiles, we show that these concentrations are not open star clusters. Instead, they appear to be field stars seen through a differentially-reddened window. We estimate that the bulk of the stars in both stellar concentrations is located at $\sim1.5$ kpc from the Sun, a distance consistent with that of the Sgr-Car arm in that direction. This low-absorption window allows one to probe into distant parts of the disk besides the Sgr-Car arm, probably the tangent part of the Sct-Cru arm, and/or the far side of the Sgr-Car arm in that direction. The main sequence associated to the Sgr-Car arm is reddened by \ebv\sim0.5, so that this window through the disk is comparable in reddening to Baade's window to the bulge. We also investigate the nature of the open cluster candidate Ru 166. The presently available data do not allow us to conclude whether Ru 166 is an actual open cluster or field stars seen through a small-scale low-absorption window

MANEJO DEL CICLO DE VIDA EN PRODUCTOS AGRÍCOLAS: CASO CACAO EN NORTE DE SANTANDER

La presente investigación presenta los resultados de la aplicación del concepto de Manejo del Ciclo de Vida (MCV) en el sector agrícola, haciendo especial énfasis en los aspectos ambientales y socioeconómicos de la toma de decisiones en la producción del cacao en Colombia. Tal evaluación  estuvo  basada  en  la  aplicación  de  dos herramientas metodológicas: Análisis del Ciclo de Vida (ACV) el cuál considera los impactos ambientales a lo largo del ciclo de vida  del  sistema  productivo del  cacao;  y la Función de Pérdida de Taguchi (FPT), la cual mide los impactos económicos generados cuando un proceso se desvía de su producción objetivo. Los resultados demostraron que el logro de mejoras apropiadas en las prácticas agronómicas y en el consumo de insumos son factores facilitadores en la toma de decisiones agrícola hacia la sostenibilidad. Para propósitos de agronegocio, tal cambio cualitativo permite no solo satisfacer las demandas del consumidor por productos ambientalmente amigables, sino además aumentar la productividad y competitividad de la producción de cacao, todo lo cual le ha conferido al MCV una amplia aceptación internacional

Climate vulnerability, impacts and adaptation in Central and South America coastal areas

© 2019 Elsevier B.V. Low-Elevation Coastal Zones in Central and South America are exposed to climate-related hazards (sea-level rise, climate variability and storms) which threaten the assets (people, resources, ecosystems, infrastructure, and the services they provide), and are expected to increase due to climate change. A non-systematic review is presented focusing on vulnerability elements, impacts, constraints to adaptation, and their possible strategies. The analysis emphasises the Intergovernmental Panel on Climate Change Reasons for Concern (e.g., threatened systems, extreme events, aggregated impacts, and critical thresholds), particularly on sea-level rise, degradation of mangroves, and invasive alien species in Central and South America focusing on case studies from Uruguay and Venezuela. Despite recent advances in coastal adaptation planning in Central and South America, there is an adaptation deficit in the implementation of measures and strategies against climate-related hazards, such as sea-level rise. Adaptation constraints are linked with poverty, resource allocation, lack of political will, and lack of early warning systems for climate-related hazards. Non-structural adaptation measures such as community-based adaptation and ecosystem-based adaptation are not fully mainstreamed into national plans yet. Government-level initiatives (e.g. National Adaptation Programmes of Action) are being developed, but a few are already implemented. In addition to specific thematic measures, the implementation of non-structural approaches, National Adaptation Programmes of Action and early warning systems, based on the reasons for concern, should foster adaptive capacity in coastal areas

Biofunctionalized Zinc Oxide Field Effect Transistors for Selective Sensing of Riboflavin with Current Modulation

Zinc oxide field effect transistors (ZnO-FET), covalently functionalized with single stranded DNA aptamers, provide a highly selective platform for label-free small molecule sensing. The nanostructured surface morphology of ZnO provides high sensitivity and room temperature deposition allows for a wide array of substrate types. Herein we demonstrate the selective detection of riboflavin down to the pM level in aqueous solution using the negative electrical current response of the ZnO-FET by covalently attaching a riboflavin binding aptamer to the surface. The response of the biofunctionalized ZnO-FET was tuned by attaching a redox tag (ferrocene) to the 3′ terminus of the aptamer, resulting in positive current modulation upon exposure to riboflavin down to pM levels

Technical summary

Human interference with the climate system is occurring. Climate change poses risks for human and natural systems. The assessment of impacts, adaptation, and vulnerability in the Working Group II contribution to the IPCC's Fifth Assessment Report (WGII AR5) evaluates how patterns of risks and potential benefits are shifting due to climate change and how risks can be reduced through mitigation and adaptation. It recognizes that risks of climate change will vary across regions and populations, through space and time, dependent on myriad factors including the extent of mitigation and adaptation

Transitions of cardio-metabolic risk factors in the Americas between 1980 and 2014

Describing the prevalence and trends of cardiometabolic risk factors that are associated with non-communicable diseases (NCDs) is crucial for monitoring progress, planning prevention, and providing evidence to support policy efforts. We aimed to analyse the transition in body-mass index (BMI), obesity, blood pressure, raised blood pressure, and diabetes in the Americas, between 1980 and 2014