1,402 research outputs found

    Evolución futura del sistema de generación colombiano en ambiente de competencia

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    Los sistemas de generación de energía eléctrica han sido manejados tradicionalmente en América Latina dentro del sector público de manera centralizada. Sin embargo, en muchos países se está replanteando el esquema de propiedad de esos sistemas buscando entre otras cosas disminuir el tamaño del sector público, aumentarla eficiencia del servicio y captar recursos para otros desarrollos sociales. Más que un proceso de privatización se busca introducir competencia en esos sistemas para llevarlos a una estructura de mercado abierto. En Colombia estos cambios se han iniciado recientemente. En lugar de planificar se buscan instrumentos que permitan visualizar la evolución de esos sistemas en el nuevo ambiente de competencia de tal manera que si esa evolución no es apropiada el gobierno pueda actuar oportunamente.) Una aproximación al modelamiento de la evolución de la capacidad de generación del Sector Eléctrico Colombiano en ambientes de competencia se desarrolla en este documento usando un modelo en dinámica de sistemas. Se presentan algunos resultados preliminares con algunas conclusiones y recomendaciones.Electric generation systems has been managed in Latin America as public own utilities. Recently in several countries the public ownership of the utilities is being questioned looking to diminish the size of the public sector, to gain efficiency and to have additional resources for other sectors. What is wanted is to introduce competition in those sectors through a market economy system. In Colombia these changes has already being introduced in the electric generation systems. The central government needs a tool that will allow them to follow the evolution of the utilities capacity in the new competition environment, so that if it is not appropriate then the government can take the conective measures. A model that represents the evolution of the Colombian Electric Sector, based in system dynamics is presented. Some model results are presented whit some cónclusions and recommendations

    Increased Compulsivity in Adulthood after Early Adolescence Immune Activation: Preclinical Evidence

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    Immune activation during early developmental stages has been proposed as a contributing factor in the pathogenesis of neuropsychiatric conditions such as obsessive-compulsive disorder, attention-deficit/hyperactivity disorder, and autism in both human and animal studies. However, its relationship with the vulnerability to inhibitory control deficit, which is a shared feature among those conditions, remains unclear. The present work studied whether postnatal immune activation during early adolescence, combined with exposure to early-life adverse events, could lead to adult vulnerability to impulsive and/or compulsive behaviors. Male Wistar rats were exposed to lipopolysaccharide (LPS) in early adolescence at postnatal day 26 (PND26). During peripuberal period, half of the animals were exposed to a mild stress protocol. In adulthood, behavioral assessment was performed with the aid of the sustained attentional 5-choice serial reaction time (5-CSRT) task, schedule-induced polydipsia (SIP), and open-field locomotor activity and novelty reactivity. Rats exposed to LPS showed more compulsive responses than their control counterparts on 5-CSRT task, although no differences were observed in SIP or locomotor responses. Our study contributes to the knowledge of the relationship between immune activation and inhibitory control deficit. Future studies should aim to disentangle how, and to what extent, immune activation impacts behavior, and to understand the role of early life mild stress

    Experimental and Computational Studies on the Performance of Solar Trackers Under Vortex Shedding, Torsional Divergence, and Flutter

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    [Abstract] The current development of renewable energies has originated a number of new structural typologies that are the physical support of the energy production systems. Photovoltaic energy is a very mature source and it is obtained using rows of panels implemented in a longitudinal grillage. Many studies have been carried out in the past with an aim to improve the capacity to obtain electrical power, but another important issue is the need to guarantee the performance of these industrial facilities under the phenomena induced by the turbulent wind flow, taking into account the fact that they are usually built in wide open spaces. This paper describes an extensive research carried out on two configurations of solar trackers by experimental and computational methods. The former was composed of a number of tests of reduced models of segments of the solar trackers, which were carried out in an aerodynamic wind tunnel. The latter consisted of a series of structural analyses worked out through a finite element model of the full panel subjected to aerodynamic and aeroelastic loads. Several angles of attack of the wind flow and a wide range of wind speeds were included in the study. This approach allowed to clearly evaluate the structural and dynamic performance of both the configurations of solar trackers under the most important wind-induced phenomena such as vortex shedding, torsional divergence, and flutter. The paper relates the phases of the study and informs about the more relevant numerical results obtained in the experiments and the computer analysis

    Factores asociados a la lactancia materna en mujeres de un municipio colombiano

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    Introducción:la lactancia materna es una de las estrategias más costo-efectivas para disminuir la morbimortalidad infantil. UNICEF afirma que la Lactancia Materna Exclusiva  en la población infantil mundial fue 38%. La Encuesta Nacional de Demografía y Salud reportó que Caldas-Risaralda-Quindío tienen la menor duración de Lactancia Materna en Colombia, y la Lactancia Materna Exclusiva en Risaralda es de 2.1 meses.Identificar los factores que determinaron la adherencia y el abandono de la lactancia materna y el papel del profesional de la salud, en madres de dos comunidades de Dosquebradas, Colombia. Métodos: estudio de corte transversal sobre una muestra de 117 madres de niños a quienes a se aplicó una encuesta que indagó por aspectos biopsicosociales que impactan sobre la lactancia materna. Resultados:la  duración de la lactancia materna exclusiva tuvo una mediana de 5 meses y la complementaria una mediana de 10 meses. La principal causa de adherencia fue “es el alimento ideal” (27,9 %) y de abandono fue “poca producción de leche” (58,1 %). Los factores que impactaron significativamente la duración la lactancia materna exclusiva fueron la ocupación de la madre, incomodidad al lactar, uso de sucedáneos de la leche y tiempo de lactancia materna complementaria. El papel del profesional de salud no impactó la duración de la lactancia materna. Conclusiones: existe una amplia brecha entre lo recomendado por la Organización Mundial de la Salud y lo practicado por las comunidades

    Factores asociados a la lactancia materna en mujeres de un municipio colombiano

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    Introducción:la lactancia materna es una de las estrategias más costo-efectivas para disminuir la morbimortalidad infantil. UNICEF afirma que la Lactancia Materna Exclusiva  en la población infantil mundial fue 38%. La Encuesta Nacional de Demografía y Salud reportó que Caldas-Risaralda-Quindío tienen la menor duración de Lactancia Materna en Colombia, y la Lactancia Materna Exclusiva en Risaralda es de 2.1 meses.Identificar los factores que determinaron la adherencia y el abandono de la lactancia materna y el papel del profesional de la salud, en madres de dos comunidades de Dosquebradas, Colombia. Métodos: estudio de corte transversal sobre una muestra de 117 madres de niños a quienes a se aplicó una encuesta que indagó por aspectos biopsicosociales que impactan sobre la lactancia materna. Resultados:la  duración de la lactancia materna exclusiva tuvo una mediana de 5 meses y la complementaria una mediana de 10 meses. La principal causa de adherencia fue “es el alimento ideal” (27,9 %) y de abandono fue “poca producción de leche” (58,1 %). Los factores que impactaron significativamente la duración la lactancia materna exclusiva fueron la ocupación de la madre, incomodidad al lactar, uso de sucedáneos de la leche y tiempo de lactancia materna complementaria. El papel del profesional de salud no impactó la duración de la lactancia materna. Conclusiones: existe una amplia brecha entre lo recomendado por la Organización Mundial de la Salud y lo practicado por las comunidades

    Impact of preemptive hospitalization on health outcomes at the temporary COVID-19 hospital in Mexico City: a prospective observational study.

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    INTRODUCTION: In response to the evolution of the coronavirus disease 2019 (COVID-19) pandemic, the admission protocol for the temporary COVID-19 hospital in Mexico City has been updated to hospitalize patients preemptively with an oxygen saturation (SpO2) of >90%. METHODS: This prospective, observational, single-center study compared the progression and outcomes of patients who were preemptively hospitalized versus those who were hospitalized based on an SpO2 ⩽90%. We recorded patient demographics, clinical characteristics, COVID-19 symptoms, and oxygen requirement at admission. We calculated the risk of disease progression and the benefit of preemptive hospitalization, stratified by CALL Score: age, lymphocyte count, and lactate dehydrogenase (<8 and ⩾8) at admission. RESULTS: Preemptive hospitalization significantly reduced the requirement for oxygen therapy (odds ratio 0.45, 95% confidence interval 0.31-0.66), admission to the intensive care unit (ICU) (0.37, 0.23-0.60), requirement for invasive mechanical ventilation (IMV) (0.40, 0.25-0.64), and mortality (0.22, 0.10-0.50). Stratification by CALL score at admission showed that the benefit of preemptive hospitalization remained significant for patients requiring oxygen therapy (0.51, 0.31-0.83), admission to the ICU (0.48, 0.27-0.86), and IMV (0.51, 0.28-0.92). Mortality risk remained significantly reduced (0.19, 0.07-0.48). CONCLUSION: Preemptive hospitalization reduced the rate of disease progression and may be beneficial for improving COVID-19 patient outcomes

    CIBERER : Spanish national network for research on rare diseases: A highly productive collaborative initiative

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    Altres ajuts: Instituto de Salud Carlos III (ISCIII); Ministerio de Ciencia e Innovación.CIBER (Center for Biomedical Network Research; Centro de Investigación Biomédica En Red) is a public national consortium created in 2006 under the umbrella of the Spanish National Institute of Health Carlos III (ISCIII). This innovative research structure comprises 11 different specific areas dedicated to the main public health priorities in the National Health System. CIBERER, the thematic area of CIBER focused on rare diseases (RDs) currently consists of 75 research groups belonging to universities, research centers, and hospitals of the entire country. CIBERER's mission is to be a center prioritizing and favoring collaboration and cooperation between biomedical and clinical research groups, with special emphasis on the aspects of genetic, molecular, biochemical, and cellular research of RDs. This research is the basis for providing new tools for the diagnosis and therapy of low-prevalence diseases, in line with the International Rare Diseases Research Consortium (IRDiRC) objectives, thus favoring translational research between the scientific environment of the laboratory and the clinical setting of health centers. In this article, we intend to review CIBERER's 15-year journey and summarize the main results obtained in terms of internationalization, scientific production, contributions toward the discovery of new therapies and novel genes associated to diseases, cooperation with patients' associations and many other topics related to RD research

    Clonal chromosomal mosaicism and loss of chromosome Y in elderly men increase vulnerability for SARS-CoV-2

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    The pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2, COVID-19) had an estimated overall case fatality ratio of 1.38% (pre-vaccination), being 53% higher in males and increasing exponentially with age. Among 9578 individuals diagnosed with COVID-19 in the SCOURGE study, we found 133 cases (1.42%) with detectable clonal mosaicism for chromosome alterations (mCA) and 226 males (5.08%) with acquired loss of chromosome Y (LOY). Individuals with clonal mosaic events (mCA and/or LOY) showed a 54% increase in the risk of COVID-19 lethality. LOY is associated with transcriptomic biomarkers of immune dysfunction, pro-coagulation activity and cardiovascular risk. Interferon-induced genes involved in the initial immune response to SARS-CoV-2 are also down-regulated in LOY. Thus, mCA and LOY underlie at least part of the sex-biased severity and mortality of COVID-19 in aging patients. Given its potential therapeutic and prognostic relevance, evaluation of clonal mosaicism should be implemented as biomarker of COVID-19 severity in elderly people. Among 9578 individuals diagnosed with COVID-19 in the SCOURGE study, individuals with clonal mosaic events (clonal mosaicism for chromosome alterations and/or loss of chromosome Y) showed an increased risk of COVID-19 lethality

    La magia de tus pensamientos : poesías & cuentos

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    Recopilación de poesías y cuentos realizados por aprendices del SENA de los programas de Mantenimiento de Motores Diesel, Técnico en Sistemas, Automatización Industrial, Electricidad Industrial, Diseño e Integración de Automatismos Mecatrónicos, Mantenimiento de Equipo Biomédico, Animación 3D, Manejo Ambiental, Diseño e integración de Automatismos Mecatrónicos y Mantenimiento mecatrónico automotriz, entre 2015 y 2017.Poesías 2018 -- Dándome tu vida / Brayan Orlando Jaimes Chaparro -- Tierra infinita / Christian Ricardo Caballero Villamizar -- Lamento a la tierra / Jeferson Alexis Montoya Moreno -- Conciencia por favor / Daniel Rincón -- Salvar un hogar llamado tierra / William Gamboa Arguello -- Planeta tierra / Iván Arley jurado -- Salvemos nuestro planeta / Jonathan David Silva -- Tierra bella / Martin Santiago -- Mi planeta / Fabián Moreno -- Generando conciencia / José Alberto Lizarazo -- Añoranza / Javier Casanova -- Sin tierra… / Gustavo Andrés Rodríguez Mendoza -- Planeta vivo y limpio / Yesid Serrano -- Palabras del destino / Osneider David Hernández Otalvaro -- Planeta tierra / Luis Fernando Isidro -- Medio ambiente / Yorgin David Hernández -- Prevenir / Brayan Mauricio Sanmiguel Luengas -- Nada será cómo antes / Jaime Andres Rodriguez Parrado -- Yo…Sol / Jonathan Bautista -- Lamento / Héctor Mauricio Parra Cuesta -- Nuestro hogar / Juan José Amaya -- Te agradecemos / Edwin Andrés Navarro Rozo, Anderson Cardozo Villamizar -- HErmoso milagro / Jhonatan Jaimes Solano -- El creador / Ana Rosa Hernández Santana -- Cuentos 2015 -- Juventud en la zona azul / Jeniffer Solano Ardila -- Los Ucayali y los Cubeo / Oscar Ivan Rueda Quintero -- Vientos de armonía / Ever Edinson Monsalve Salcedo -- El nacimiento de una nueva era / Carlos Leonardo Ardila Alvarado -- Luz de sueños / Hugo Andrés Álvarez -- Sol de medio día / Claudia Ramírez Guarín -- Cuentos 2016 -- Mucha verraquera mano / Héctor Josué Amado Sandoval -- El viaje de irse y nunca volver / Dayana Marcela Fuentes Duran -- “Santander es hermosa” / Kelly Tatiana Pabón Blanco -- Los valores del SENA / Ana Rosa Hernandez Santana -- La fuerza del espiritu y el deseo de cambiar / Pablo Andrés Capera Rodríguez -- SENA, paz y reconciliación / Adrián Benítez R., Rubén Darío Martínez -- Cuentos 2017 -- Cartas a un pasado / Angelita Delgado Pérez -- ¿Por qué así? ¿por qué tan blanco? ¿por qué no de otra manera? / Cristian Felipe Vargas Buenahora -- El gato pacho pacho, el gato más pacho de todos los pachos / Edwin Matajira García -- Freeland “el paraíso perdido” / Dámaso Antonio Morales Palacin -- Un mundo al revés / Fabio Eduardo Contreras Piñeresna91 página

    Search for dark matter produced in association with bottom or top quarks in √s = 13 TeV pp collisions with the ATLAS detector

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    A search for weakly interacting massive particle dark matter produced in association with bottom or top quarks is presented. Final states containing third-generation quarks and miss- ing transverse momentum are considered. The analysis uses 36.1 fb−1 of proton–proton collision data recorded by the ATLAS experiment at √s = 13 TeV in 2015 and 2016. No significant excess of events above the estimated backgrounds is observed. The results are in- terpreted in the framework of simplified models of spin-0 dark-matter mediators. For colour- neutral spin-0 mediators produced in association with top quarks and decaying into a pair of dark-matter particles, mediator masses below 50 GeV are excluded assuming a dark-matter candidate mass of 1 GeV and unitary couplings. For scalar and pseudoscalar mediators produced in association with bottom quarks, the search sets limits on the production cross- section of 300 times the predicted rate for mediators with masses between 10 and 50 GeV and assuming a dark-matter mass of 1 GeV and unitary coupling. Constraints on colour- charged scalar simplified models are also presented. Assuming a dark-matter particle mass of 35 GeV, mediator particles with mass below 1.1 TeV are excluded for couplings yielding a dark-matter relic density consistent with measurements
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