Fuga de cerebros en el sector salud: ¿Un fenómeno que condiciona el desarrollo en América Latina?

This article aims to find variables that explain the brain drain in the health sector in Latin America. At work, are made econometric estimates for 20 countries in Latin America with purpose of finding a parsimonious explanation of the brain drain and how it can affect infant mortality or life expectancy. The conclusion differs depending on the estimation method used, panel or in three stages least squares.El presente artículo tiene por objetivo encontrar variables que expliquen la fuga de cerebros en el sector salud para los países de América Latina. En el trabajo se realizan estimaciones econométricas para 20 países de América Latina, con objetivo de encontrar una explicación parsimoniosa de la fuga de cerebros y cómo puede afectar la mortalidad infantil o la esperanza de vida. Las conclusiones a las que se arriban varían según el método econométrico utilizado: panel ó mínimos cuadrados en tres etapas

Placenta previa como factor de riesgo para presentación de nalgas en la gestante de edad avanzada

Objetivo. Determinar si la placenta previa es factor de riesgo para presentación podálica en la gestante de edad avanzada. Material y Métodos. Se realizó un estudio de cohortes retrospectivas en el periodo de enero 2012 a diciembre del 2017, utilizando el sistema informativo perinatal (SIP) una gran base de datos; la muestra estuvo conformada por 70 gestantes con placenta previa (cohorte 1) y 70 gestantes sin placenta previa (cohorte 2). Los criterios de exclusión fueron malformación fetal y antecedente de cesárea previa. Se definieron y compararon seis categorías para las características maternas encontradas en las gestantes con placenta previa. Los factores de riesgo para presentación podálica, se evaluaron para diferentes grupos mediante un análisis estratificado. Resultados. La edad materna promedio de gestantes con placenta previa fue de 38,33± 2,78 (p=0,926), se encontraron 16 casos de presentación podálica, en el grupo de gestantes con placenta previa (N=70) y 7 casos en el grupo sin placenta previa (N=70) apreciándose una diferencia significativa (p=<0,05), el riesgo relativo para la placenta previa fue de 2,28 (IC 95 % 1,00 - 5,21). Respecto al índice de masa corporal y el peso del recién nacido, se encontró relación con el grupo de gestantes con placenta previa con diferencia significativa (p=<0,05). Para el resto de características no hubo hallazgos significativos igualmente en el análisis multivariado. Conclusiones. La placenta previa es un factor de riesgo para presentación podálica en la gestante de edad avanzada en el Hospital Belén de Trujillo. La incidencia de gestantes expuestas y no expuestas fue de 30 % y 10 % respectivamente. La incidencia de gestantes con placenta previa fue más elevada en comparación con las gestantes sin placenta previa.Objective. To determine if placenta previa is a risk factor for breech presentation in the pregnant woman of advanced age. Material and methods. A retrospective cohort study was conducted in the period from January 2012 to December 2017, using the perinatal information system (SIP) a large database; the sample consisted of 70 pregnant women with placenta previa (cohort 1) and 70 pregnant women without placenta previa (cohort 2). Exclusion criteria were fetal malformation and antecedent of previous cesarean section. Six categories were defined and compared for the maternal characteristics found in pregnant women with placenta previa. The risk factors for breech presentation were evaluated for different groups through a stratified analysis. Results The average maternal age of pregnant women with placenta previa was 38.33 ± 2.78 (p = 0.926), 16 cases of breech presentation were found in the group of pregnant women with placenta previa (N = 70) and 7 cases in the group without placenta previa (N = 70) with a significant difference of p = <0.05, the relative risk for placenta previa was 2.28 (95% CI 1.00-5.21). Newborn weight, there was a relationship with the group of pregnant women with placenta previa with a significant difference (p = <0.05) .For the rest of the characteristics, there were no significant findings in the multivariate analysis. Conclusions. Placenta previa is a risk factor for breech presentation in the elderly pregnant woman in the Belén de Trujillo Hospital. The incidence of exposed and unexposed pregnant women was 30% and 10% respectively. The incidence of pregnant women with placenta previa was higher in comparison with pregnant women without placenta previa.Tesi

Gestión por procesos y productividad una revisión bibliográfica a nivel Latinoamérica en los 10 últimos años

This article analyzes process management and productivity as key elements to achieve organizational success. Emphasis is placed on theoretically substantiating how these tools are associated with each other, to fulfill their purpose. The research begins with the bibliographical review of scientific articles that are related to the topic of analysis, applying inclusion and exclusion criteria such as year of publication, relationship with the topic and variables to be investigated. For this purpose, various reliable information search engines were used, such as Google Scholar, Dialnet and Redalyc. As a consequence of the analysis, 60 articles were extracted, of which 16 were selected for review. Therefore, and from the corresponding analysis, it is concluded that process management and productivity are basic tools for achieving business success, noting a positive and complementary relationship between them.El presente artículo analiza la gestión por procesos y la productividad como elementos claves para lograr el éxito organizacional. Se enfatiza en fundamentar teóricamente cómo estas herramientas se asocian entre sí, para cumplir con su propósito. La investigación inicia con la revisión bibliográfica de artículos científicos que guardan relación con el tema materia de análisis, aplicando criterios de inclusión y exclusión como año de publicación, relación con el tema y variables a investigar. Par dicho fin, se utilizaron diversos motores de búsqueda de información confiable como Google Académico, Dialnet y Redalyc. Como consecuencia del análisis, se extrajeron 60 artículos, de los cuales 16 fueron seleccionados para su revisión. Por lo tanto, y del análisis correspondiente se concluye que la gestión por procesos y la productividad son herramientas básicas para el logro del éxito empresarial, advirtiéndose una relación positiva y complementaria entre éstas

Starting points in plant-bacteria nitrogen-fixing symbioses: intercellular invasion of the roots

Agricultural practices contribute to climate change by releasing greenhouse gases such as nitrous oxide that are mainly derived from nitrogen fertilizers. Therefore, understanding biological nitrogen fxation in farming systems is benefcial to agriculture and environmental preservation. In this context, a better grasp of nitrogen-fxing systems and nitrogen-fxing bacteria-plant associations will contribute to the optimization of these biological processes. Legumes and actinorhizal plants can engage in a symbiotic interaction with nitrogen-fxing rhizobia or actinomycetes, resulting in the formation of specialized root nodules. The legume-rhizobia interaction is mediated by a complex molecular signal exchange, where recognition of different bacterial determinants activates the nodulation program in the plant. To invade plants roots, bacteria follow different routes, which are determined by the host plant. Entrance via root hairs is probably the best understood. Alternatively, entry via intercellular invasion has been observed in many legumes. Although there are common features shared by intercellular infection mechanisms, differences are observed in the site of root invasion and bacterial spread on the cortex reaching and infecting a susceptible cell to form a nodule. This review focuses on intercellular bacterial invasion of roots observed in the Fabaceae and considers, within an evolutionary context, the different variants, distribution and molecular determinants involved. Intercellular invasion of actinorhizal plants and Parasponia is also discussed.Fil: Ibañez, Fernando Julio. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas, Fisicoquímicas y Naturales. Departamento de Ciencias Naturales; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba; ArgentinaFil: Wall, Luis Gabriel. Universidad Nacional de Quilmes; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Fabra, Adriana Isidora. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas, Fisicoquímicas y Naturales. Departamento de Ciencias Naturales; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba; Argentin

Root Architecture and Morphology of Advanced Synthetic Lines Developed by the Red Clover Breeding Program of INIA-Chile

Red clover (Trifolium pratense L.) is one of the most important forage legumes in temperate regions of the world. In Chile, it is the only forage species with a breeding program that has been continue over decades and produced commercial cultivars. Because of the good seed and forage production potential, red clover cultivars released by the INIA breeding program (INIA-BP) are commercialized both in Chile and abroad. The main limitation of the species worldwide is its low persistence, determined by the high plant mortality due to the deterioration of the main root and crown (Ortega et al., 2014). In the last 26 years, the red clover INIA-BP has improved the productivity and persistence of the species, achieving high genetic gains (Ortega et al., 2014). However, selection methodology until now has not considered consistently phenotyping of roots, even though root architecture and morphology could be related to plant adaptation as described for other species. Therefore, the objective of this work was to characterize the root architecture and morphology of seven advanced synthetic lines (ASLs) of red clover developed by INIA-BP and four commercial cultivars

Nitrogen Use Efficiency and Root Dry Matter Partitioning in Four Perennial Temperate Forage Grass Species

In Chile, the livestock systems based on perennial swards (grasses/white clover) have intensified its production because of the indiscriminated increases in nitrogen fertilization (Vistoso et al., 2012). Currently, new agronomic practices are demanded to allow the increase of the Nitrogen Use Efficiency (NUE) of perennial swards. In livestock systems, NUE can be studied and improved at animal, soil and plant level. In Chile, the two first levels have been broadly studied (Vistoso et al., 2012) but the plant contribution has been ignored. Today, a lot of cultivars from temperate grass species originated from different part of the world are commercialized in Chile. The objective of this work was to evaluate the NUE of four perennial forage grasses species and to determinate the role of the root system

Understanding the large shift photocurrent of WS2_{2} nanotubes: A comparative analysis with monolayers

We study the similarities and differences in the shift photocurrent contribution to the bulk photovoltaic effect between transition-metal dichalcogenide monolayers and nanotubes. Our analysis is based on density functional theory in combination with the Wannier interpolation technique for the calculation of the shift photoconductivity tensor. Our results show that for nanotube radii of practical interest $r>60$~\AA, the shift photoconductivity of a single-wall nanotube is well described by that of the monolayer. Additionally, we quantify the shift photocurrent generated under realistic experimental conditions like device geometry and absorption capabilities. We show that a typical nanotube can generate a photocurrent of around 10 nA, while the monolayer only attains a maximum of 1 nA. This enhancement is mainly due to the larger conducting cross section of a nanotube in comparison to a monolayer. Finally, we discuss our results in the context of recent experimental measurements on WS$_{2}$ monolayer and nanotubes[Zhang et al., Nature 570, 349 (2019)].Comment: 11 pages, 9 figure

Possibilities of the use of CeBr3 scintillation detectors for the measurement of the content of radionuclides in samples for environmental monitoring

The investigation of radioactivity in samples is an application of gamma-ray spectrometry dealing with low and very low level gamma-ray activities of different isotopes. Gamma-ray spectrometry performed in the framework of radiological environmental monitoring may be done after selective sampling processes or after a chemical purification of a sample. Both cases imply that only some specific radionuclides should contribute to the obtained spectrum. Gamma-ray spectrometry performed with medium energy resolution detectors may allow the possible distinction of their photopeaks. Therefore, a cerium bromide (CeBr3) detector can be particularly attractive for routine tasks in radiological environmental monitoring as it has a high efficiency, medium energy resolution and it can work at room temperature. This study describes the conditions under which a CeBr3 detector can serve for some routine analysis in radiological analysis of samples collected in the environment or collected by airsamplers in environmental radiological monitoring programmes