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The small hydroelectric power plants (SHPP) are implemented in non-interconnected zones (NIZ) of developing countries. In which, the provision of electrical energy from the national interconnected system is not economically feasible. Therefore, in the literature, hydroelectric generation technologies have been implemented taking advantage of the energy available in the rivers. One of these technologies is the Michell-Banki type cross-flow turbines (MBT), which, despite having lower efficiencies than turbines such as Pelton and Francis, maintain their efficiency although fluctuations in site conditions. For this reason, different studies have been made to increase the efficiency of the MBT by making geometric modifications to both the nozzle and the rotor. The purpose of this study is to determine numerically the effect of the geometry of the blades that form the runner on the efficiency of Michell-Banki Turbine (MBT). For this, two (2) geometries were studied corresponding to a circular sector of a standard tubular profile and an airfoil NACA 6512 modified in curvature profile and chord length, according to the profile of the standard tubular blade. For this study, transient simulations for multiphase water-air flow were implemented using a k-ε turbulence model in the Ansys 2020R1® CFX software. The two (2) turbine models were configured to the same hydraulic conditions of head and volumetric flow corresponding to 0.5 m and 16.27 L/s, respectively. Variations in rotational speed were configured between 100 and 200 RPM with 20 RPM steps. It was found that using the modified 6512 hydrodynamic profile, at 140 RPM increased efficiency by 6 %, compared to the conventional tubular type blade geometry

BACKGROUND: Perioperative corticosteroid use may reduce acute kidney injury. We sought to test whether methylprednisolone reduces the risk of acute kidney injury after cardiac surgery. METHODS: We conducted a prespecified substudy of a randomized controlled trial involving patients undergoing cardiac surgery with cardiopulmonary bypass (2007-2014); patients were recruited from 79 centres in 18 countries. Eligibility criteria included a moderate-to-high risk of perioperative death based on a preoperative score of 6 or greater on the European System for Cardiac Operative Risk Evaluation I. Patients (n = 7286) were randomly assigned (1:1) to receive intravenous methylprednisolone (250 mg at anesthetic induction and 250 mg at initiation of cardiopulmonary bypass) or placebo. Patients, caregivers, data collectors and outcome adjudicators were unaware of the assigned intervention. The primary outcome was postoperative acute kidney injury, defined as an increase in the serum creatinine concentration (from the preoperative value) of 0.3 mg/dL or greater (≥ 26.5 μmol/L) or 50% or greater in the 14-day period after surgery, or use of dialysis within 30 days after surgery. RESULTS: Acute kidney injury occurred in 1479/3647 patients (40.6%) in the methylprednisolone group and in 1426/3639 patients (39.2%) in the placebo group (adjusted relative risk 1.04, 95% confidence interval 0.96 to 1.11). Results were consistent across several definitions of acute kidney injury and in patients with preoperative chronic kidney disease. INTERPRETATION: Intraoperative corticosteroid use did not reduce the risk of acute kidney injury in patients with a moderate-to-high risk of perioperative death who had cardiac surgery with cardiopulmonary bypass. Our results do not support the prophylactic use of steroids during cardiopulmonary bypass surgery. Trial registration: ClinicalTrials.gov, no. NCT00427388. ispartof: CANADIAN MEDICAL ASSOCIATION JOURNAL vol:191 issue:9 pages:E247-E256 ispartof: location:Canada status: published

Nitrogen (N) is a critical macronutrient for plants and its utilization is fundamental to crop productivity. In the last decades, N fertilizers have been extensively used to increase both grain yield and grain protein content in wheat, helping support the human population growth while causing a serious pollution problem. Wheat is one of the most used cereal crops for the important amount of proteins it provides in human diet, and durum wheat (Triticum turgidum ssp. durum) is particularly important in the Mediterranean region for the production of pasta and other typical dishes. In order to use gene knowledge to improve N-use efficiency, it is crucial to increase the understanding of how this crop responds to growth under different N conditions. Here, high-throughput sequencing was used to provide a determination of transcript levels of N-starvation-induced genes. We constructed 24 cDNA libraries from roots, leaves/stems, flag leaf and spike of durum wheat cultivar Svevo plants grown under N-deficient or standard conditions during the grain filling stage. A RNA-Seq experiment on three biological replicates for each tissue provided a large amount of sequencing data, which were used for a differential expression analysis. A total of 4968 transcripts were found differentially expressed between treated and control samples. Among them, 3270 belonged to root tissues, while the other 1698 were genes found in leaves/stems, flag leaf and spike tissues. Results highlighted that 3057 genes were differentially expressed uniquely in root tissues, 681 in leaves/stems, 298 in flag leaf and 234 only in spike tissues. The Gene Ontology analysis revealed a number of categories involved in N-stress in all organ types, the most frequent down-regulated transcripts functioned for thiamin biosynthetic and metabolic processes, photosynthesis, protein processing, localization and maturation, photorespiration, respiratory chain. Other categories such as CTP biosynthetic and metabolic processes, DNA synthesis, and amino acid metabolism were also represented. Selected genes were analysed in quantitative PCR in order to confirm their expression levels. Our results provide valuable information about N-starvation-responsive genes involved in different genetic pathways and concerning several plant organs of durum wheat. This data will help shed light on signal transduction pathways related to N-utilization and will be useful for identifying candidate genes for crop breeding.

El artículo presenta una síntesis de la investigación sobre representaciones de movilidad social en personas migrantes e hijos de migrantes afrodescendientes en el municipio de Tuluá - Valle del Cauca. Con base en herramientas de análisis cualitativas aplicadas a información recabada sobre un grupo de afrodescendientes residentes en el municipio, el autor analiza algunas manifestaciones discursivas que hablan de representaciones de movilidad social y su relación con la condición étnico racial. Entre los hallazgos se puede resaltar la disonancia entre la percepción positiva y las evidencias de una micromovilidad ascendente de hombres migrantes y sus familias, y la insatisfacción y el no logro o logro parcial de las pretensiones de movilidad tanto de los hijos/nietos de migrantes como de mujeres cabeza de hogar afrodescendientes en la ciudad de Tuluá. The article presents a synthesis of research on social mobility representations of migrants and children of migrants of African descent in the town of Tuluá - Valle del Cauca. Based on qualitative analysis tools applied to information gathered about a group of African descent residents in the city, the author analyzes some discursive manifestations that speak of representations of social mobility and its relationship to racial ethnic condition. Among the findings can highlight the dissonance between the positive perception and evidence of an upward micromobility migrant men and their families, and dissatisfaction and no accomplishment or partial accomplishment of the pretensions of mobility of the children / grandchildren of migrants and of women heads of household of African descent in the city of Tuluá. O artigo apresenta uma síntese da pesquisa sobre representações de mobilidade social em pessoas migrantes e filhos de migrantes afrodescendentes no município de Tuluá -Valle del Cauca. Com base em ferramentas de análise qualitativas aplicadas à informação coletada sobre um grupo de afrodescendentes residentes no município, o autor analisa algumas manifestações discursivas que falam de representações de mobilidade social e sua relação com a condição étnico racial. Entre os descobrimentos pode-se destacar a dissonância entre a percepção positiva e as evidências de micro mobilidade ascendente de homens migrantes e suas famílias, e a insatisfação e a não conquista ou conquista parcial das pretensões de mobilidade tanto dos filhos/netos de migrantes como de mulheres chefes de família - mães solteiras- afrodescendentes na cidade de Tuluá.

Objetivo. Presentar algunas reflexiones preliminares del trabajo decampo realizado en el municipio de Tuluá en el marco de la investigaciónsobre representaciones de movilidad social en migrantes e hijos de migrantesafrodescendientes. Metodología. Se trata de un estudio cualitativo a partirde un conjunto de doce entrevistas en profundidad y dos grupales sobrelas cuales se realizó el análisis de algunas manifestaciones discursivas quehablan de representaciones de la condición étnico-racial en relación con lasituación social y económica de las personas afro en la ciudad. Resultadosy conclusiones. Entre las conclusiones se destaca el señalamiento que hacenlas personas entrevistadas a la estructura social y a los códigos culturalesracializados como principio y fundamento de la desigualdad y el cierre deoportunidades para ellos, individualmente y como grupo. No obstante, lasexperiencias, prácticas, significados y consecuencias de la discriminación seperciben diferencialmente según la cohorte generacional de la que se hagaparte. Objetive: To present some preliminary reflections about the fieldwork carried out in the municipality of Tuluá in the framework of the research project on representations of social mobility of African descendant migrants and migrants’ children. Methodology: This is a qualitative study based on a set of twelve personal interviews and two group interviews, on which the analysis of some discursive manifestations that talk about representations of ethnic-racial conditions in relation to the social and economic situation of the Afro people in the city is carried out. Results and conclusions: Among the findings, the affirmation interviewees make to the racialized social structure and cultural codes as principle and foundation of inequality and closing of opportunities for them individually and as a group stands out. However, experiences, practices, meanings and consequences of discrimination are perceived differently according to the generational cohort from whom it is part.

Objective. To establish current knowledge about Colombian bee-pollen from a point of view nutritional and functional, contributing towards creating national technical standards and the identification of chemical differentiation factors for further researches. Material and methods. One hundred ninety-six samples of dried bee pollen were collected in the center region of Colombia known as Cundi-boyacense high plateau, where nearly 90% of total bee pollen production is concentrated in this country. Performed physicochemical analyses in this study were: moisture, pH, acidity, ash, carbohydrates, lipids, proteins, dietary fiber, fatty acid profile and mineral elements. Results. Bee pollen from this region had 7.7±5.2 g/100 g moisture content, and a following centesimal composition based on dry matter: ashes 2.5±0.4 g; lipids 6.90±3.5 g; proteins 23.8±3.2 g and total dietary fiber 14.5±3.5 g. The most abundant fatty acids were α-linolenic, palmitic and linoleic. Carbohydrates were the main components and fructose and glucose the most concentrated sugars. The predominant minerals assessed here were potassium, calcium and magnesium. The results were also discussed in terms of the characteristics found in Colombian bee-pollen in comparison to international regulations and findings for other varieties of commercial bee-pollen from eight different countries. Conclusions. The results found in this study suggest that bee-pollen may be used as a dietary supplement and agree with bibliographical reports and international regulations. Such characterization will enable to be proposed technical standards in line with Colombian bee-pollen properties and it is expected to improve marketing and production chain conditions. Objetivos. Generar conocimiento actualizado sobre el polen colombiano desde un punto de vista nutricional y funcional, contribuyendo a la creación de estándares técnicos nacionales y la identificación de factores químicos de diferenciación para futuras investigaciones. Materiales y métodos. Ciento noventa y seis muestras de polen seco fueron recolectadas en la región central de Colombia conocida como el altiplano cundiboyacense, donde se concentra cerca del 90% de la producción total en este país. Los análisis fisicoquímicos realizados en este estudio fueron: humedad, pH, acidez, cenizas, carbohidratos, lípidos, proteínas, fibra dietaria, perfil de ácidos grasos y minerales. Resultados. El polen de esta región tuvo un contenido de humedad de 7.7±5.2 g/100 g y una composición centesimal basada en materia seca: cenizas 2.5±0.4 g; lípidos 6.90±3.5 g; proteínas 23.8±3.2 g y fibra dietaria total 14.5±3.5 g. Los ácidos grasos más abundantes fueron α-linolénico, palmítico y linoleico. Los carbohidratos fueron los componentes principales con fructosa y glucosa siendo los azúcares más concentrados. Los minerales predominantes evaluados fueron potasio, calcio y magnesio. Los resultados también fueron discutidos en términos de las características encontradas en el polen colombiano en comparación a normatividades internacionales y hallazgos para otras variedades de polen comercial de ocho países diferentes. Conclusiones. Los resultados encontrados en este estudio sugieren que el polen apícola puede ser utilizado como suplemento dietario y es coherente con los reportes bibliográficos y normativas internacionales. Tal caracterización permitirá proponer estándares técnicos de acuerdo a las propiedades del polen colombiano y se espera que se mejore la comercialización y las condiciones de la cadena de producción.

En el acto quirúrgico la anestesia es un proceso que siempre conlleva riesgos. Un procedimiento común en equinos es realizar cirugías en estación para disminuir el riesgo de la anestesia general. Para los procedimientos anestésicos en estación en equinos se han utilizado las combinaciones de bolos de xilazina y anestesia local; sin embargo, la analgesia irregular y la marcada ataxia son complicaciones frecuentes. En el presente caso clínico se evaluó un protocolo de bolos de xilazina 0,6 mg/kg I.V. y morfina en infusión I.V. continua a 30 µg/kg/hora, con aplicación de anestesia local para la extraccción de un tumor de células de la granulosa en una yegua. Durante el procedimiento quirúrgico se observó una buena analgesia, sedación moderada y ataxia leve, sin alteraciones cardiovasculares o respiratorias, lo que favoreció el procedimiento quirúrgico; solamente se observó un corto periodo de amotilidad intestinal el cual fue superado espontáneamente. La yegua se recuperó totalmente del procedimiento quirúrgico y presentó evidencia de estro en dos ocasiones dentro del año siguiente a la intervención. Los procedimeintos anestésico y quirúrgico empleados en esta yegua fueron apropiados y la llevaron a su normalidad reproductiva. Anesthesia is always a procedure that leads many risks in the quirurgical act. A common procedure in horses is to make standing surgeries to decrease the general anesthesia risks. For standing anesthetic procedures in horses there have been used combinations of xilazine bolus and local anesthesia; however, irregular analgesia and marked ataxia are frequent complications. In this clinical case it was evaluate a protocol of xilazine bolus 0,6 mg/kg I.V. and a constant rate infusion of morphine 30 µg/kg/h I.V., with local anesthesia for the extraction of a granulosa cell tumor in one mare. In general, during the surgical procedure it was observed good analgesia, moderate sedation and slight ataxia, without cardiovascular or respiratory problems which favored the surgical procedure; it was observed only a short period without intestinal motility that returned to normality spontaneously. The mare recovered fully from the surgical procedure and presented evidence of estrus twice within one year after the intervention. The anesthetic and surgical procedures used in this case were appropriate and lead recovery of the normal reproductive behavior of this mare.

La anestesia es un proceso que siempre conlleva riesgos en el acto quirúrgico. Un procedimiento común en equinos es realizar cirugías en estación para disminuir el riesgo de la anestesia general. Para los procedimientos anestésicos en estación en equinos se han utilizado las combinaciones de bolos de xilazina y anestesia local, sin embargo la analgesia irregular y la marcada ataxia son complicaciones frecuentes. En el presente caso clínico se evaluó un protocolo de bolos de xilazina 0,6 mg/kg I.V. y morfina en infusión contínua a 30 µg/Kg/hora/IV, y aplicación de anestesia local para la extraccción de un tumor de células de la granulosa en una yegua. En general durante el procedimiento quirúrgico se observó una buena analgesia, sedación moderada y ataxia leve, sin alteraciones cardiovasculares o respiratorias, lo que favoreció el procedimiento quirurgico y solamente se observó un corto periodo de amotilidad intestinal el cual fue superado espontaneamente. La yegua se recuperó totalmente del procedimiento quirúrgico y presentó evidencia de estro en dos ocasiones posteriores dentro del año siguiente a la intervención. El procedimeinto anestésico y quirúrgico empleado en esta yegua fue apropiado y llevó a la normalidad reproductiva de la yegua.

EI presente artículo describe una metodología eficiente, simple y económica para la obtención de altas densidades celulares de Haemophilus influenzae, con el fin de producir vacunas tanto celulares como acelulares. Se describe un método de cultivo en líquido para este microorganismo, el cual no había sido implementado en el país. Después de varios años de investigación por parte de varios grupos, principalmente debido a los bajos rendimientos obtenidos o a los altos costos de las formulaciones más exitosas. Se evalúa el sistema, con respecto a medios sólidos y líquidos de referencia, teniendo en cuenta la cinética de crecimiento, los costos y la expresión de los antígenos más promisorios como vacuna purificada.

The present article describes an efficient, simple and unexpensive method for the production of high cellular densities of Haemophilus influenzae for cellular and cell free vaccine production. We present here a liquid culture-based method that had not been successfully implemented in Colombia, so far having given low yields and high costs. The kinetics, costs and production of the most promisory antigen candidates for vaccine production were evaluated in liquid and solid reference media. EI presente artículo describe una metodología eficiente, simple y económica para la obtención de altas densidades celulares de Haemophilus influenzae, con el fin de producir vacunas tanto celulares como acelulares. Se describe un método de cultivo en líquido para este microorganismo, el cual no había sido implementado en el país. Después de varios años de investigación por parte de varios grupos, principalmente debido a los bajos rendimientos obtenidos o a los altos costos de las formulaciones más exitosas. Se evalúa el sistema, con respecto a medios sólidos y líquidos de referencia, teniendo en cuenta la cinética de crecimiento, los costos y la expresión de los antígenos más promisorios como vacuna purificada.

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