68 research outputs found

    Assessing the burden of COVID-19 in developing countries: systematic review, meta-analysis and public policy implications

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    Trabajo realizado por otros catorce autores.Introduction The infection fatality rate (IFR) of COVID-19 has been carefully measured and analysed in high-income countries, whereas there has been no systematic analysis of age-specific seroprevalence or IFR for developing countries. Methods We systematically reviewed the literature to identify all COVID-19 serology studies in developing countries that were conducted using representative samples collected by February 2021. For each of the antibody assays used in these serology studies, we identified data on assay characteristics, including the extent of seroreversion over time. We analysed the serology data using a Bayesian model that incorporates conventional sampling uncertainty as well as uncertainties about assay sensitivity and specificity. We then calculated IFRs using individual case reports or aggregated public health updates, including age pecific estimates whenever feasible. Results In most locations in developing countries, seroprevalence among older adults was similar to that of younger age cohorts, underscoring the limited capacity that these nations have to protect older age groups. Age-specific IFRs were roughly 2 times higher than in high income countries. The median value of the population IFR was about 0.5%, similar to that of high-income countries, because disparities in healthcare access were roughly offset by differences in population age structure. Conclusion The burden of COVID-19 is far higher in developing countries than in high-income countries, reflecting a combination of elevated transmission to middle-aged and older adults as well as limited access to adequate healthcare. These results underscore the critical need to ensure medical equity to populations in developing countries through provision of vaccine doses and effective medications

    High CO2 Under Nutrient Fertilization Increases Primary Production and Biomass in Subtropical Phytoplankton Communities: A Mesocosm Approach

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    The subtropical oceans are home to one of the largest ecosystems on Earth, contributing to nearly one third of global oceanic primary production. Ocean warming leads to enhanced stratification in the oligotrophic ocean but also intensification in cross-shore wind gradients and thus in eddy kinetic energy across eastern boundary regions of the subtropical gyres. Phytoplankton thriving in a future warmer oligotrophic subtropical ocean with enhanced CO2 levels could therefore be patchily fertilized by increased mesoscale and submesoscale variability inducing nutrient pumping into the surface ocean. Under this premise, we have tested the response of three size classes (0.2-2, 2-20, and > 20 μm) of subtropical phytoplankton communities in terms of primary production, chlorophyll and cell biomass, to increasing CO2 concentrations and nutrient fertilization during an in situ mesocosm experiment in oligotrophic waters offof the island of Gran Canaria. We found no significant CO2-related effect on primary production and biomass under oligotrophic conditions (phase I). In contrast, primary production, chlorophyll and biomass displayed a significant and pronounced increase under elevated CO2 conditions in all groups after nutrient fertilization, both during the bloom (phase II) and post-bloom (phase III) conditions. Although the relative increase of primary production in picophytoplankton (250%) was 2.5 higher than in microphytoplankton (100%) after nutrient fertilization, comparing the high and low CO2 treatments, microphytoplankton dominated in terms of biomass, contributing > 57% to the total. These results contrast with similar studies conducted in temperate and cold waters, where consistently small phytoplankton benefitted after nutrient additions at high CO2, pointing to different CO2-sensitivities across plankton communities and ecosystem types in the ocean

    The Children’s Faecal Matter Structure Is Built by Their Parents

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    Introduction: Humans have gone through physical changes over the last 4 million years. The mouth, however, has not changed teeth quantity or quality. Eight incisors for fruits, vegetables and tubers; four little canines for little animals; eight premolars and twelve flat molars are used for crushing these foods, especially whole grains and legumes. The teeth crushing foods are the first step in the building of faecal matter. Foods are selected mostly according to cultural guidelines than to biological needs. The patterns of consumption are induced by the publicity of industrialized or processed foods. Material and Methods: This study design was observational, analytical, correlational, transversal and prospective. One thousand children (0 - 12 years old) were questioned in order to learn about the relationship between Weekly Eating Frequency (WEF) and Faecal Matter (FM) characteristics. The FM was classified as soft , normal or hard and the outcome was expressed as Dry Faecal Residue (DFR). The WEF and Weekly Bowel Movement Frequency (WBMF) were determined and tabulated according to times per week. Environmental factors, parents’ education level and children’s birth order were examined. Results: There was a strong association between DFR, WBMF and WEF. Environment and education level did not play a key role although birth order did matter. Conclusions: Fibre-free foods (dairies, meats, flours and sweeties or sodas) increased DFR. Foods containing fibre from vegetables decreased DFR, which in turn contributed to the WBMF. Lowest DFR was observed in children under Exclusive Breastfeeding (EB). Distant last-born children had higher DFR. Comments: Daily examples support these results and it is clear that children’s FM is built by their parents. We encourage parents to follow the “mouth nature” rather than the “advertisements nature”.Facultad de Ciencias Médicas (FCM

    The Children’s Faecal Matter Structure Is Built by Their Parents

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    Introduction: Humans have gone through physical changes over the last 4 million years. The mouth, however, has not changed teeth quantity or quality. Eight incisors for fruits, vegetables and tubers; four little canines for little animals; eight premolars and twelve flat molars are used for crushing these foods, especially whole grains and legumes. The teeth crushing foods are the first step in the building of faecal matter. Foods are selected mostly according to cultural guidelines than to biological needs. The patterns of consumption are induced by the publicity of industrialized or processed foods. Material and Methods: This study design was observational, analytical, correlational, transversal and prospective. One thousand children (0 - 12 years old) were questioned in order to learn about the relationship between Weekly Eating Frequency (WEF) and Faecal Matter (FM) characteristics. The FM was classified as soft , normal or hard and the outcome was expressed as Dry Faecal Residue (DFR). The WEF and Weekly Bowel Movement Frequency (WBMF) were determined and tabulated according to times per week. Environmental factors, parents’ education level and children’s birth order were examined. Results: There was a strong association between DFR, WBMF and WEF. Environment and education level did not play a key role although birth order did matter. Conclusions: Fibre-free foods (dairies, meats, flours and sweeties or sodas) increased DFR. Foods containing fibre from vegetables decreased DFR, which in turn contributed to the WBMF. Lowest DFR was observed in children under Exclusive Breastfeeding (EB). Distant last-born children had higher DFR. Comments: Daily examples support these results and it is clear that children’s FM is built by their parents. We encourage parents to follow the “mouth nature” rather than the “advertisements nature”.Facultad de Ciencias Médicas (FCM

    The Dynamical Behaviour of Test Particles in a Quasi-Spherical Spacetime and the Physical Meaning of Superenergy

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    We calculate the instantaneous proper radial acceleration of test particles (as measured by a locally defined Lorentzian observer) in a Weyl spacetime, close to the horizon. As expected from the Israel theorem, there appear some bifurcations with respect to the spherically symmetric case (Schwarzschild), which are explained in terms of the behaviour of the superenergy, bringing out the physical relevance of this quantity in the study of general relativistic systems.Comment: 14 pages, Latex. 4 figures. New references added. Typos corrected. To appear in Int. J. Theor. Phy

    Aplicación de diferentes metodologías en el mejoramiento de lenteja (lens culinaris medik)

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    La lenteja es un cultivo muy importante desde el comienzo de la revolución de la agricultura en el Viejo Mundo y uno de los primeros en ser domesticados junto al trigo, la cebada, la arveja y el lino. Se lo considera como uno de los cultivos más antiguos con unos 8000 a 9000 años de antigüedad. Desde el punto de vista nutricional posee un alto valor proteico (20-30%), alto contenido de carbohidratos (43-70%) y es una fuente rica en fibra dietética, antioxidantes, vitaminas y minerales esenciales en la dieta. En Argentina, la principal región productora se ubica al sur de Santa Fe (Departamentos de Caseros, Constitución, Rosario y San Lorenzo) y al norte de Buenos Aires (Partidos de Pergamino, Rojas y Salto). Aquí el cultivo se hace en forma extensiva, de secano y durante el invierno, y luego de la cosecha, se realiza la siembra de soja de segunda. El objetivo de este trabajo es realizar una compilación de las diferentes metodologías utilizadas en el mejoramiento de lenteja.Lentil (Lens culinaris Medik.) is a self-pollinating diploid (2n=2x=14) species belonging to the Fabaceae family. It is one of the oldest crops known, with 8,000 to 9,000 years of history and it is among the earliest domesticates from the Near East Fertile Crescent. The seeds have high nutritional value. This crop is an interesting substitute to wheat in cereal rotations but its importance is low due to a lack of suitable varieties with local adaptation. Some of the major problems that Argentinian lentil breeders face are the narrow genetic base of the current cultivated germplasm and its low yield potential. A lentil breeding program was initiated in 2004 to develop new varieties with adaptation to prevalent conditions in growing areas of Argentina. Germplasm was obtained from ICARDA (International Center for Agricultural Research in the Dry Areas) and local producers. Conventional breeding methods using hybridization and selection are being carried out to develop improved varieties, broad the genetic base, and isolate superior recombinant inbred lines. Two new varieties have been obtained, one of the macrosperm type (Boyerito FCA) and the other of the microsperm type (Tacuarita FCA) through the application of mass selection in F2 populations from the cross of selected materials. This program complements traditional breeding methods with biotechnological techniques such as transgenesis, use of molecular markers, in vitro embryo culture combined with the SSD method to shorten the breeding time, and digital phenotyping.Fil: Bermejo, Carolina Julieta. Universidad Nacional de Rosario. Facultad de Ciencias Agrarias. Departamento de Producción Vegetal. Cátedra de Mejoramiento Vegetal y Producción de Semillas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Investigaciones en Ciencias Agrarias de Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Agrarias. Instituto de Investigaciones en Ciencias Agrarias de Rosario; ArgentinaFil: Maglia, F.. Ministerio de Ciencia. Tecnología e Innovación Productiva. Agencia Nacional de Promoción Científica y Tecnológica; ArgentinaFil: Palacios, T.. Ministerio de Ciencia. Tecnología e Innovación Productiva. Agencia Nacional de Promoción Científica y Tecnológica; ArgentinaFil: Espósito, María Andrea. Universidad Nacional de Rosario. Facultad de Ciencias Agrarias. Departamento de Producción Vegetal. Cátedra de Mejoramiento Vegetal y Producción de Semillas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Investigaciones en Ciencias Agrarias de Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Agrarias. Instituto de Investigaciones en Ciencias Agrarias de Rosario; ArgentinaFil: Cazzola, Federico. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Investigaciones en Ciencias Agrarias de Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Agrarias. Instituto de Investigaciones en Ciencias Agrarias de Rosario; Argentina. Ministerio de Ciencia. Tecnología e Innovación Productiva. Agencia Nacional de Promoción Científica y Tecnológica; ArgentinaFil: Guindon, María Fernanda. Universidad Nacional de Rosario. Facultad de Ciencias Agrarias. Departamento de Producción Vegetal. Cátedra de Mejoramiento Vegetal y Producción de Semillas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Investigaciones en Ciencias Agrarias de Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Agrarias. Instituto de Investigaciones en Ciencias Agrarias de Rosario; ArgentinaFil: Gatti, I.. Universidad Nacional de Rosario. Facultad de Ciencias Agrarias. Departamento de Producción Vegetal. Cátedra de Mejoramiento Vegetal y Producción de Semillas; ArgentinaFil: Cointry Peix, Enrique Luis. Universidad Nacional de Rosario. Facultad de Ciencias Agrarias. Departamento de Producción Vegetal. Cátedra de Mejoramiento Vegetal y Producción de Semillas; Argentin

    Modelo de gestión organizacional: barreras y oportunidades en la conformación y fortalecimiento de una red institucional de investigación en salud

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    En este proyecto se pretende describir los factores que favorecen y/u obstaculizan la constitución de una red institucional de investigación para la salud, desde las propias expresiones de los actores/agentes del Estado (Ministerio de Salud) y de las instituciones académicas de la provincia de Mendoza. Es un estudio descriptivo de corte transversal, que realizará un análisis centrado en el concepto de problema, desde la concepción de planificación situacional. Se utilizarán técnicas de recolección de información con una metodología mixta cuanti y cualitativa. La población accesible de este estudio está conformada por las áreas de investigación formalmente establecidas, por norma, de los ministerios de Salud de las provincias de Mendoza, San Luis y La Rioja y las Universidades con sus unidades académicas y/o facultades del sector público y privado de la provincia de Mendoza, quedando excluidas las universidades y/o facultades que no posean carreras afines a la salud de la provincia de Mendoza, y el área de investigación del ministerio de Salud de San Juan por no contar con referente técnico de investigación a nivel ministerial. Se pretende indagar sobre factores que permitan la posterior elaboración de indicadores para medir las acciones de la red local y la posible construcción de una red regional como política de Salud

    Reliable Activation of Immature Neurons in the Adult Hippocampus

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    Neurons born in the adult dentate gyrus develop, mature, and connect over a long interval that can last from six to eight weeks. It has been proposed that, during this period, developing neurons play a relevant role in hippocampal signal processing owing to their distinctive electrical properties. However, it has remained unknown whether immature neurons can be recruited into a network before synaptic and functional maturity have been achieved. To address this question, we used retroviral expression of green fluorescent protein to identify developing granule cells of the adult mouse hippocampus and investigate the balance of afferent excitation, intrinsic excitability, and firing behavior by patch clamp recordings in acute slices. We found that glutamatergic inputs onto young neurons are significantly weaker than those of mature cells, yet stimulation of cortical excitatory axons elicits a similar spiking probability in neurons at either developmental stage. Young neurons are highly efficient in transducing ionic currents into membrane depolarization due to their high input resistance, which decreases substantially in mature neurons as the inward rectifier potassium (Kir) conductance increases. Pharmacological blockade of Kir channels in mature neurons mimics the high excitability characteristic of young neurons. Conversely, Kir overexpression induces mature-like firing properties in young neurons. Therefore, the differences in excitatory drive of young and mature neurons are compensated by changes in membrane excitability that render an equalized firing activity. These observations demonstrate that the adult hippocampus continuously generates a population of highly excitable young neurons capable of information processing

    The Children’s Faecal Matter Structure Is Built by Their Parents

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    Introduction: Humans have gone through physical changes over the last 4 million years. The mouth, however, has not changed teeth quantity or quality. Eight incisors for fruits, vegetables and tubers; four little canines for little animals; eight premolars and twelve flat molars are used for crushing these foods, especially whole grains and legumes. The teeth crushing foods are the first step in the building of faecal matter. Foods are selected mostly according to cultural guidelines than to biological needs. The patterns of consumption are induced by the publicity of industrialized or processed foods. Material and Methods: This study design was observational, analytical, correlational, transversal and prospective. One thousand children (0 - 12 years old) were questioned in order to learn about the relationship between Weekly Eating Frequency (WEF) and Faecal Matter (FM) characteristics. The FM was classified as soft , normal or hard and the outcome was expressed as Dry Faecal Residue (DFR). The WEF and Weekly Bowel Movement Frequency (WBMF) were determined and tabulated according to times per week. Environmental factors, parents’ education level and children’s birth order were examined. Results: There was a strong association between DFR, WBMF and WEF. Environment and education level did not play a key role although birth order did matter. Conclusions: Fibre-free foods (dairies, meats, flours and sweeties or sodas) increased DFR. Foods containing fibre from vegetables decreased DFR, which in turn contributed to the WBMF. Lowest DFR was observed in children under Exclusive Breastfeeding (EB). Distant last-born children had higher DFR. Comments: Daily examples support these results and it is clear that children’s FM is built by their parents. We encourage parents to follow the “mouth nature” rather than the “advertisements nature”.Facultad de Ciencias Médicas (FCM
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