Producción de etanol a partir de la cáscara de banano y de almidón de yuca

En este trabajo se evaluó la hidrólisis ácida del almidón presente en yuca y de la celulosa presente en cáscara de banano y su posterior fermentación a etanol, se ajustaron los medios de fermentación para los microorganismos Saccharomyces cerevisiae NRRL Y-2034 y Zymomonas mobilis CP4. Se caracterizó la cáscara de banano, la cual posee un contenido de almidón, celulosa y hemicelulosa que representan más del 80 % de la cáscara ameritando el estudio de ésta como fuente de carbono. La hidrólisis ácida de cáscara de banano produce 20 g/l de azúcares reductores. Para la Yuca con 170 g/l de almidón a; pH 0.8 en 5 horas se logra conversión completa a azúcares reductores y no se nota ningún efecto inhibitorio por parte de los cultivos realizados con cáscara de banano y yuca por la presencia de cianuro en la yuca y por la formación de compuestos tóxicos al hidrolizar la celulosa en banano. Para la fermentación realizada con Sacharomyces cerevisiae se logra una concentración de etanol de 7.92±0.31% y no se aprecia una producción considerable de etanol (menor de 0.1 g/l) para ninguno de los medios fermentados con Zymomonas mobilis

Biomass Accumulation and Carbon Storage in Pinus maximinoi, Quercus robur, Quercus rugosa, and Pinus patula from Village- Forests of Chiapas, Mexico

The Frailesca region (Chiapas, Mexico) presents a lack of forest studies and its environmental contribution. This chapter displays a first case study with preliminary research information regarding the identification of main forest trees and rural villages with best potential for biomass production and carbon storage management. Twenty two plots of 500 m2 were selected in 11 villages of the region, in order to identify the main and dominant forest trees species and then to estimate the biomass production and carbon storage in pine (Pinus maximinoi), oak (Quercus robur), holm oak (Quercus rugosa) and Mexican weeping pine (Pinus patula) species. This study shows that the largest accumulation of both biomass and carbon occurred in the pine forests and the lowest in the oak forests. Pine trees showed carbon storage of 516.75 Mg ha−1, followed by holm oaks, with 297.21 Mg ha−1; the species with the lowest value was oak, with 75.02 Mg ha−1. The forests of the 24 de Febrero villages had the highest potential for carbon storage. Deep studies are being conducted in relation to the aboveground biomass, carbon contents in trees stem, branches and leaves, and the relation to biomass dynamics and carbon stocks and other ecological aspects of village-forests

Ruling Frameworks and Fire Use‐Conflicts in Tropical Forests of Chiapas, Mexico: A Discourse Analysis

The use of fire within tropical forests to settle agriculture and livestock systems has long been causing a bottle-neck for governmental and environmental development agencies, especially in natural forested areas with local population. An international strategy followed since many years ago is the decree of special territories with vast forests as natural protected areas (NPA). In Mexico, environmental laws can run contrary to customs and practices of natural resource-dependent communities which still use fire to farm their lands as unique livelihood activity. The chapter examines two conflicting frameworks of resource management (forest and soil) and governance in a forest village’s efforts to comply with federal policies against fires in a NPA of Chiapas, Mexico. Forest and soil management is a key locus in California village, where governance structures come into conflict with hierarchical State power. Participatory workshops and semi-structured interviews were primary research instruments for data collection and discovery of community front and backstage. Ethnography and discourse analysis were used as main tools for the analysis of information. While the State leads the conservation efforts and limits cultural activities and local actions through coercive laws, the land use and resource-dependent communities defend their access rights, and they also determine how to individual or collectively manage fires in daily activities. Finding collective solutions with horizontal-dialogue strategies represent an important issue and a pending task for the development and preservation agencies focused on forested areas. Backstage dialogue is a tool for village self-preservation when livelihood strategies are at odds with protectionist conservation efforts

Manual del cultivo de café en el VRAEM

El Comité Especial de Articulación Intergubernamental (CEAI –VRAEM), pone a disposición de los productores, profesionales e interesados el “Manual del Cultivo de Café en el VRAEM”, con la finalidad de orientar y unificar los conocimientos y criterios técnicos para la correcta instalación, manejo y beneficio del cultivo de café, priorizando su difusión responsable en el campo para los agricultores, técnicos y especialistas. Este manual consta de cuatro capítulos: I. Establecimiento del cultivo. II. Manejo del Cultivo de Café. III. Cosecha y post cosecha del café. IV. Referencias bibliográficas

Influencia de la hipoxia hipobárica aguda en el ciclo menstrual de mujeres jóvenes en el año 2018

OBJETIVO: Determinar la influencia de la hipoxia hipobárica aguda en el ciclo menstrual de mujeres jóvenes. MATERIALES Y MÉTODOS: Diseño observacional. Se seleccionaron 21 mujeres, divididas en dos grupos. A 15 participantes en fase menstrual (G1) se les proporcionó un sistema de puntuación (pictograma) que midió el flujo menstrual y un test de escala del dolor. Las mediciones se realizaron a 34 m s.n.m y posteriormente a más de 2500 m s.n.m; utilizándose la prueba de Mann-Whitney con p<0.05. A 6 participantes (G2) se les realizó una ecografía antes y después de la exposición a gran altura con el fin de conocer su influencia sobre la ovulación mediante la Prueba Exacta de Fisher con p<0.05. RESULTADOS: La puntuación promedio del pictograma obtenida en G1 a 34 m s.n.m fue de 17.033, mientras que a más de 2500 m s.n.m se obtuvo 13.967 (p=0.349). Para el test de escala del dolor p=0.3436. Las ecografías a 34 m.s.n.m mostraron en G2 folículo óptimo (> 18 mm) para la ovulación. Después de la exposición a gran altura, en 4 de las participantes se observó folículos entre 2-6 mm, con ausencia de cuerpo lúteo; por el contrario, en las restantes se evidenció la presencia del cuerpo lúteo. El análisis estadístico para G2 mostró p= 0.03. CONCLUSIONES: No se encontró una relación significativa entre la hipoxia hipobárica aguda y variación del flujo y dolor menstrual debido al limitado tamaño muestral. Sin embargo, se evidenció una influencia negativa de la hipoxia hipobárica aguda sobre el desarrollo de la ovulación.PALABRAS CLAVE: hipoxia hipobárica aguda, ciclo menstrual

Consenso colombiano de atención, diagnóstico y manejo de la infección por SARS-COV-2/COVID-19 en establecimientos de atención de la salud Recomendaciones basadas en consenso de expertos e informadas en la evidencia

The “Asociación Colombiana de Infectología” (ACIN) and the “Instituto de Evaluación de Nuevas Tecnologías de la Salud” (IETS) created a task force to develop recommendations for Covid 19 health care diagnosis, management and treatment informed, and based, on evidence. Theses reccomendations are addressed to the health personnel on the Colombian context of health services. © 2020 Asociacion Colombiana de Infectologia. All rights reserved

Hyperoxemia and excess oxygen use in early acute respiratory distress syndrome : Insights from the LUNG SAFE study

Publisher Copyright: © 2020 The Author(s). Copyright: Copyright 2020 Elsevier B.V., All rights reserved.Background: Concerns exist regarding the prevalence and impact of unnecessary oxygen use in patients with acute respiratory distress syndrome (ARDS). We examined this issue in patients with ARDS enrolled in the Large observational study to UNderstand the Global impact of Severe Acute respiratory FailurE (LUNG SAFE) study. Methods: In this secondary analysis of the LUNG SAFE study, we wished to determine the prevalence and the outcomes associated with hyperoxemia on day 1, sustained hyperoxemia, and excessive oxygen use in patients with early ARDS. Patients who fulfilled criteria of ARDS on day 1 and day 2 of acute hypoxemic respiratory failure were categorized based on the presence of hyperoxemia (PaO2 > 100 mmHg) on day 1, sustained (i.e., present on day 1 and day 2) hyperoxemia, or excessive oxygen use (FIO2 ≥ 0.60 during hyperoxemia). Results: Of 2005 patients that met the inclusion criteria, 131 (6.5%) were hypoxemic (PaO2 < 55 mmHg), 607 (30%) had hyperoxemia on day 1, and 250 (12%) had sustained hyperoxemia. Excess FIO2 use occurred in 400 (66%) out of 607 patients with hyperoxemia. Excess FIO2 use decreased from day 1 to day 2 of ARDS, with most hyperoxemic patients on day 2 receiving relatively low FIO2. Multivariate analyses found no independent relationship between day 1 hyperoxemia, sustained hyperoxemia, or excess FIO2 use and adverse clinical outcomes. Mortality was 42% in patients with excess FIO2 use, compared to 39% in a propensity-matched sample of normoxemic (PaO2 55-100 mmHg) patients (P = 0.47). Conclusions: Hyperoxemia and excess oxygen use are both prevalent in early ARDS but are most often non-sustained. No relationship was found between hyperoxemia or excessive oxygen use and patient outcome in this cohort. Trial registration: LUNG-SAFE is registered with ClinicalTrials.gov, NCT02010073publishersversionPeer reviewe

Colombian consensus recommendations for diagnosis, management and treatment of the infection by SARS-COV-2/ COVID-19 in health care facilities - Recommendations from expert´s group based and informed on evidence

La Asociación Colombiana de Infectología (ACIN) y el Instituto de Evaluación de Nuevas Tecnologías de la Salud (IETS) conformó un grupo de trabajo para desarrollar recomendaciones informadas y basadas en evidencia, por consenso de expertos para la atención, diagnóstico y manejo de casos de Covid 19. Estas guías son dirigidas al personal de salud y buscar dar recomendaciones en los ámbitos de la atención en salud de los casos de Covid-19, en el contexto nacional de Colombia

XVI International Congress of Control Electronics and Telecommunications: "Techno-scientific considerations for a post-pandemic world intensive in knowledge, innovation and sustainable local development"

Este título, sugestivo por los impactos durante la situación de la Covid 19 en el mundo, y que en Colombia lastimosamente han sido muy críticos, permiten asumir la obligada superación de tensiones sociales, políticas, y económicas; pero sobre todo científicas y tecnológicas. Inicialmente, esto supone la existencia de una capacidad de la sociedad colombiana por recuperar su estado inicial después de que haya cesado la perturbación a la que fue sometida por la catastrófica pandemia, y superar ese anterior estado de cosas ya que se encontraban -y aún se encuentran- muchos problemas locales mal resueltos, medianamente resueltos, y muchos sin resolver: es decir, habrá que rediseñar y fortalecer una probada resiliencia social existente - producto del prolongado conflicto social colombiano superado parcialmente por un proceso de paz exitoso - desde la tecnociencia local; como lo indicaba Markus Brunnermeier - economista alemán y catedrático de economía de la Universidad de Princeton- en su libro The Resilient Society…La cuestión no es preveerlo todo sino poder reaccionar…aprender a recuperarse rápido.This title, suggestive of the impacts during the Covid 19 situation in the world, and which have unfortunately been very critical in Colombia, allows us to assume the obligatory overcoming of social, political, and economic tensions; but above all scientific and technological. Initially, this supposes the existence of a capacity of Colombian society to recover its initial state after the disturbance to which it was subjected by the catastrophic pandemic has ceased, and to overcome that previous state of affairs since it was found -and still is find - many local problems poorly resolved, moderately resolved, and many unresolved: that is, an existing social resilience test will have to be redesigned and strengthened - product of the prolonged Colombian social conflict partially overcome by a successful peace process - from local technoscience; As Markus Brunnermeier - German economist and professor of economics at Princeton University - indicates in his book The Resilient Society...The question is not to foresee everything but to be able to react...learn to recover quickly.Bogot

A current controller for a grid-tied, cascade multilevel inverter

A cascade multilevel inverter is simulated and implemented to supply power to the grid from a set of 4 isolated batteries. The phase-shifted carrier PWM modulation strategy is employed in this article, increasing the frequency of the output current. A PI controller is applied to achieve a connection to the grid. Simulation results supplying current on phase, leading and lagging are shown, and experimental results validate the prototype built