251 research outputs found

    Movilización de conciencia comunitaria: Una experiencia de Investigación Acción Participativa

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    17 p.La investigación que se presenta a continuación tuvo dos fases, con sus respectivos objetivos: primero, los objetivos de diagnóstico, orientados a conocer las necesidades, problemáticas y potencialidades de la comunidad de la vereda El Charquito, para realizar junto con ellos el diagnóstico psicosocial; y, segundo, los objetivos de intervención, orientados a fomentar la participación y el compromiso de los actores internos de la vereda El Charquito para transformar de forma positiva las problemáticas identificadas en el diagnóstico de necesidades.Introducción Método Resultados y discusión Construcción de categorías inductivas o emergentes Alcance de la intervención en la comunidad Construcción de conocimiento con la comunidad Ámbitos de transformación en la vereda El Charquito Conclusiones y aportes Referencia

    Effect of Bay Leaves Essential Oil Concentration on the Properties of Biodegradable Carboxymethyl Cellulose-Based Edible Films

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    Films containing bay leaves essential oils (BEOs) were prepared and evaluated for edible packaging applications. The BEOs were extracted by the Soxhlet method, using ethanol or methanol as organic solvent. Then, films were prepared by “solvent casting” technique using carboxymethyl cellulose (CMC), with different concentrations for the as-obtained BEOs (from 1% to 30% wt.). The resulting films were characterized to evaluate their physical (thickness, moisture content, water solubility and water vapor permeability), optical (transparency and UV-light barrier), mechanical (tensile strength and elongation at break), antioxidant and antimicrobiological properties Attractive films were obtained for food active packaging applications, as they presented a high antioxidant activity (up to 99%) and total phenolic content, and good barrier properties against water vapor (50% improved of CMC) in the case of CMC-film containing 15% wt. ethanolic extract. Related to optical properties, UV-light barrier effect was increased (almost 100% of protection) avoiding typical lipids oxidation in food systems. High water solubility (93%) was also found, ensuring also their biodegradability. Moreover, it was demonstrated that developed films inhibit microorganisms’ growth (Escherichia coli and Candida glabrata), this avoiding an early food oxidation

    Mechanochemical Preparation of Novel Polysaccharide-Supported Nb2O5 Catalysts

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    Polysaccharides extracted from natural sources can be used as starting material for the preparation of nanoparticle supported composites. A novel family of bio-nanocomposites was mechanochemically synthesized by using niobium oxide and enzymatically produced polysaccharides. The structural, textural and surface properties of nanomaterials, were determined by X-Ray diffraction (XRD), nitrogen adsorption-desorption (N_2 porosimetry), pulse chromatography, infrared spectroscopy (ATR-IR) and dynamic light scattering (DLS). Selective oxidation of isoeugenol to vanillin was carried out to demonstrate the catalytic activity of the Nb-polysaccharides nanocomposites. Interestingly, most of our material showed high conversion of isoeugenol (60–70%) with selectivity to vanillin over 40%. The optimum conversion and selectivity were achieved with a reaction time between 8 and 24 h

    Gestión de residuos químicos en instituciones educativas

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    The present article shows the relation of the educative institutions and the environmental and social responsibilities due to hazardous waste generated in laboratories. Laboratories' hazardous waste should be disposed in a manner meeting local and state regulations. This article sets the standard for the beginning of the development of the project "Dangerous and ordinary design of a plan of handling of the chemical substances, remainders generated in the building of laboratories of Macarena B of the Distrital University"El presente artículo busca la reflexión por parte de las instituciones educativas, en relación con la gran responsabilidad ambiental y social que cada una tiene con la gestión adecuada de los residuos peligrosos generados en sus laboratorios. Gestión esta que debe ser innovadora, económica y de acuerdo a las necesidades propias, pero cumpliendo con las disposiciones legales vigentes. Este artículo es uno de los productos resultado del desarrollo de la investigación Diseño de un plan de manejo de las sustancias químicas, residuos peligrosos y ordinarios generados en el edificio de laboratorios de la Macarena B de la Universidad Distrital

    Myocardial injury determination improves risk stratification and predicts mortality in COVID-19 patients

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    Background: Despite being associated with worse prognosis in patients with COVID-19, systematic determination of myocardial injury is not recommended. The aim of the study was to study the effect of myocardial injury assessment on risk stratification of COVID-19 patients.Methods: Seven hundred seven consecutive adult patients admitted to a large tertiary hospital with confirmed COVID-19 were included. Demographic data, comorbidities, laboratory results and clinical outcomes were recorded. Charlson comorbidity index (CCI) was calculated in order to quantify the degree of comorbidities. Independent association of cardiac troponin I (cTnI) increase with outcomes was evaluated by multivariate regression analyses and area under curve. In addition, propensity-score matching was performed to assemble a cohort of patients with similar baseline characteristics.Results: In the matched cohort (mean age 66.76 ± 15.7 years, 37.3% females), cTnI increase above the upper limit was present in 20.9% of the population and was associated with worse clinical outcomes, including all-cause mortality within 30 days (45.1% vs. 23.2%; p = 0.005). The addition of cTnI to a multivariate prediction model showed a significant improvement in the area under the time-dependent receiver operating characteristic curve (0.775 vs. 0.756, DC-statistic = 0.019; 95% confidence interval 0.001–0.037). Use of renin–angiotensin–aldosterone system inhibitors was not associated with mortality after adjusting by baseline risk factors.Conclusions: Myocardial injury is independently associated with adverse outcomes irrespective of baseline comorbidities and its addition to multivariate regression models significantly improves their performance in predicting mortality. The determination of myocardial injury biomarkers on hospital admission and its combination with CCI can classify patients in three risk groups (high, intermediate and low) with a clearly distinct 30-day mortality

    Uso de las TIC de acuerdo a los estilos de aprendizaje de docentes y discentes

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    La presente investigación tiene como objetivo identificar las TIC que utilizan los profesores y los alumnos del Colegio de Postgraduados de acuerdo a sus Estilos de Aprendizaje. Para comenzar se hace una revisión de conceptos sobre Estilo y Estilos de Aprendizaje. Después, se hace el planteamiento de los objetivos e hipótesis de la investigación y la metodología empleada. Al final se muestran los resultados obtenidos, las conclusiones y las fuentes documentales

    Advances in Improving Tolerance to Waterlogging in \u3cem\u3eBrachiaria\u3c/em\u3e Grasses

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    Poor drainage is found on about 11.3% of agricultural land in Latin America where physiography promotes flooding, high groundwater tables, or stagnant surface water (waterlogging). Waterlogging drastically reduces oxygen diffusion into the soil causing hypoxia which is the main limitation that reduces root aerobic respiration and the absorption of minerals and water. Under waterlogging conditions plants can adapt with traits and mechanisms that improve root aeration such as production of aerenchyma and development of adventitious roots. During the rainy season Brachiaria pastures are exposed to waterlogging conditions that can severely limit pasture productivity and hence animal production. The main objective of an inter-institutional and multidisciplinary project was to identify Brachiaria hybrids combining waterlogging tolerance with high forage yield and quality to improve meat and milk production and mitigate the impacts of climate change in the humid areas of Latin America. Researchers at the Centro Internacional de Agricultura Tropical (CIAT) have developed a screening method to evaluate waterlogging tolerance in Brachiaria. Using this method, 71 promising hybrids derived from three Brachiaria species (B. ruziziensis, B. brizantha, and B. decumbens) were evaluated. Four hybrids were identified as superior in waterlogging tolerance. Their superiority was based on greater green leaf biomass production, a greater proportion of green leaf to total leaf biomass, greater green leaf area, leaf chlorophyll content, and photosynthetic efficiency, and reduced dead leaf biomass. These hybrids together with previously selected hybrids and germplasm accessions are being field-tested for waterlogging tolerance in collaboration with National Agricultural Research Institutions and farmers from Colombia, Nicaragua, and Panama

    Micro-morphologies, habitats and associated biodiversity in a fluid venting submarine structure using ROV underwater images: Mercator mud volcano (Gulf of Cádiz)

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    Mercator mud volcano has been explored by direct visual observations using a ROV at 350 to 370 m depth. Underwater images, taken mainly at the summit, have allowed characterizing the fluid venting environment, where different microforms, habitats and associated biota, with typical seepage components have been identified. Chemosynthetic bacterial communities were detected and sampled at the northeastern side of the summit at 350 m, next to pockmark-like depressions with diameters ranging 1 to 3 m, bioturbation marks, sediment mounds and authigenic carbonates of different sizes (0.1-5m length). Chemosynthesis-based communities were mainly composed by bacterial mats (patch diameter 10-30 cm), however some remains of cold seep chemosymbiotic bivalves (Lucinoma asapheus) were also found on the sediment. Habitat types at Mercator MV are influenced by oceanographic and sedimentation processes deposition and favouring fauna colonizing diverse substrate types, such as large sponges on slabs and sea-pens and annelids on soft bottoms

    Soluble concentrations of the terminal complement complex C5b-9 correlate with end-organ injury in preeclampsia

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    Q3Q1Pacientes embarazadas hipertensasObjective: We sought to determine if soluble levels of C5b-9, the terminal complement complex, correlate with end-organ injury in preeclampsia. Study Design: Project COPA (Complement and Preeclampsia in the Americas), a multi-center observational study in Colombia from 2015 to 2016, enrolled hypertensive pregnant women into four groups: chronic hypertension, gestational hypertension, preeclampsia, and preeclampsia with severe features. Trained coordinators collected clinical data, blood and urine. End-organ injury was defined by serum creatinine ≥ 1.0 mg/dl, aspartate transaminase ≥ 70U/L, platelet count < 150,000/µl, or lactate dehydrogenase ≥ 500 U/L. Data were analyzed by χ2 or Fisher’s exact test with significance at P < 0.05. Main Outcome Measure: C5b-9 concentrations in plasma and urine, using enzyme linked immunosorbent assays. Results: In total, 298 hypertensive participants were enrolled. Plasma and urine C5b-9 levels were measured in all participants and stratified by quartile (Q1-4), from lowest to highest C5b-9 concentration. Participants with low plasma C5b-9 levels (Q1) were more likely to have end-organ injury compared to those with higher levels (Q2-Q4) [platelet count < 150,000/μl (20.8% vs. 8.4%, P = 0.01); elevated serum creatinine ≥ 1.0 mg/dl (14.9% vs. 4.5%, P = 0.009)]. In contrast, participants with high urinary C5b-9 levels (Q4) were more likely to have end-organ injury compared to those with lower levels (Q1-Q3) [platelet count < 150,000/μl (19.7% vs. 7.4%, P = 0.003); elevated serum creatinine ≥ 1.0 mg/dl (12.3% vs. 4.4%, P = 0.025)]. Conclusion: We identified a pattern of increased urine and low plasma C5b-9 levels in patients with preeclampsia and end-organ injury. Soluble C5b-9 levels may be used to identify complement-mediated end-organ injury in preeclampsia.https://orcid.org/0000-0001-6822-0374Revista Internacional - IndexadaA1N

    A relict oasis of living deep-sea mussels Bathymodiolus and microbial-mediated seep carbonates at newly-discovered active cold seeps in the Gulf of Cádiz, NE Atlantic Ocean

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    Extensive beds of the deep-sea mussel Bathymodiolus mauritanicus (currently also known as Gigantidas mauritanicus) linked to active cold seeps related to fissure-like activity on Al Gacel mud volcano, Gulf of Cádiz, were filmed and sampled for the first time during the oceanographic expedition SUBVENT-2 aboard R/V Sarmiento de Gamboa. Al Gacel mud volcano is one of up to 80 fluid venting submarine structures (mud volcanoes and mud volcano/diapir complexes) identified in the Gulf of Cádiz as result of explosive venting of hydrocarbon-enriched fluids sourced from deep seated reservoirs. This mud volcano is a cone-shaped edifice, 107 m high, 944 m in diameter constituted by mud breccias and, partially covered by pavements of seep carbonates. Extensive beds of this deep-sea mussel were detected at the northern flank at 810–815 m water depth associated with bacterial mats around intermittent buoyant vertical bubble methane plumes. High methane concentrations were measured in the water column above living mussel beds. Other chemosymbiotic species (Siboglinum sp., Solemya elarraichensis, Isorropodon sp., Thyasira vulcolutre and Lucinoma asapheus) were also found in different parts of Al Gacel mud volcano. Al Gacel mud volcano may currently represent one of the most active mud volcanoes in the Gulf of Cádiz, delivering significant amounts of thermogenic hydrocarbon fluids which contribute to foster the extensive chemosynthesis-based communities detected. This finding is of paramount importance for linking extremophile bivalve populations along the North Atlantic, including cold seeps of the Gulf of México, hydrothermal vents of the Mid-Atlantic Ridge and now, detailed documented at the Gulf of Cádiz.Versión del edito
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