Galactic perturbations on the population of wide binary stars with exoplanets
Correa Otto, Jorge Alfredo; Gil Hutton, Ricardo Alfredo
Aims. The aim of this work is to study the dynamical effects of the Galaxy on binary star systems with physical and orbital characteristics similar to those of the population of known wide binary stars with exoplanets. As secondary goal we analyse the possible consequences on the stability of a hypothetical planetary system orbiting one of the stellar components. Methods. We numerically reproduced the temporal evolution of a sample of 3 × 105 binary star systems disturbed by the Galactic potential and passing stars in an environment similar to the solar neighbourhood. Results. Our results show that the dynamical evolution of the population of wide binary stars with exoplanets in the solar neighbourhood is modelled by the process of disruption of binary star systems induced by the Galaxy. We found that this process depends mainly on the separation between both stars, whereas it is almost independent of the initial orbital configuration. Moreover, our calculations are in agreement with the results of previous works regarding the indirect influence of the Galaxy on the stability of planetary systems in wide binary stars. However, the effects on the planetary region show a dependence on the initial configuration of binary stars. Finally, we obtain an indirect test of the impulse approximation model for dynamical studies of binary star systems.
Extreme cold events in South America analyzed from a GFDL model perspective: comparison between CMIP3 and CMIP5 climate scenarios
Muller, Gabriela Viviana; Rabelo Da Rocha Repinaldo, Cintia; Araneo, Diego Christian
This paper deals with the future change projections of extreme cold events in relation to historical climate simulations, based on the comparison between two versions of the GFDL model, CMIP3 and CMIP5, in three regions of southeastern South America where these events are frequent. To this end, the compositions of up to five extreme events below 0 °C at 850 hPa were considered. They were derived from daily data collected from May to September of the NCEP/NCAR reanalysis and GFDL Coupled Atmospheric and Oceanic Global Circulation Model. The study periods run from 1961 to 1990 and from 2081 to 2100 for the most critical scenarios: A2 (GFDL-CM2) and RCP8.5 (GFDL-CM3). Sea level pressure, temperature, and wind were analyzed at 850 hPa and wind also at 250 hPa, for each of the areas under study, representing tropical (Area 1) and subtropical (Area 2 and Area 3) latitudes. The ability of the model to simulate the historical climate, represented by the reanalysis, increased as latitude decreased, CM3 version being better for subtropical latitudes than CM2. Depending on GFDL model version, temperature was higher or lower than those shown by the reanalysis in the tropical latitudes. In contrast, at subtropical latitudes, both versions of the model present lower values. An increase in mean temperature is expected in the future in the three areas, mainly at tropical latitudes (Area 1) according to both versions of the model, which is in line with the results reported by other global models. In Area 2, a further increase in temperature is projected in CM3 version, while, for Area 3, the greatest projection is in CM2 version. Changes are expected for the future climate, primarily explained by the configuration of the circulation fields, such as in the case of the subtropical areas in CM2, whose pattern is more related to that typically associated with radiative cooling, rather than the advective cooling shown in the historical climate. This result is in contrast with the results of the CM3 version, which displays a pattern associated with cold air advection from the south for both the historical and future climate. As regards the tropical area, both versions of the model reveal a considerable reduction in the number of extreme cold events.
Tamizaje del cáncer de mama: certezas y controversias
Luthy, Isabel Alicia
El cáncer de mama es globalmente el de mayor incidencia en mujeres, con estimaciones de entre 1.7 y 2.4 millones de casos anuales según diferentes fuentes1, 2. También es globalmente la principal causa de muerte por cáncer con unas 523 000 muertes anuales2. Según información del Instituto Nacional del Cáncer de la Argentina, en el año 2012 (último dato disponible) se registraron alrededor de 20 000 nuevos casos de cáncer de mama (que representa el 32.2% de los cánceres en mujeres), mientras que en 2016 se registraron 5645 fallecimientos de mujeres (19.4% de las muertes por cáncer considerando solamente ese sexo) y 45 de hombres por esta enfermedad. Probablemente estas cifras se encuentren subestimadas.
Se publicaron una serie de trabajos que pusieron en duda la conveniencia del tamizaje del cáncer de mama, fundamentalmente debido al sobrediagnóstico y el consecuente sobretratamiento (revisado en4). Si se impone esta política tan contraria al concepto de medicina preventiva, ¿no veremos aumentar nuevamente las tasas de mortalidad que se mantenían constantes, aunque la incidencia seguía incrementándose?
El Fondo para la Investigación Científica y Tecnológica (FONCyT) anuncia los resultados del proceso de procesabilidad de la convocatoria PICT 2017.
El organismo dedicado a promover el financiamiento de proyectos para la generación de conocimiento y la mejora de los sistemas productivos participó del encuentro de nanotecnología más grande de Latinoamérica.
La Agencia Nacional de Promoción Científica y Tecnológica participó de la 15° Feria Internacional de Productos, Equipos y Servicios para la Salud que se realizó del 27 al 29 de septiembre en el Centro de Exposiciones de Costa Salguero.
El Fondo Fiduciario de Promoción de la Industria del Software (FONSOFT) anuncia el resultados del proceso de reconsideracion y evaluacion para la convocatoria Emprendedores FONSOFT 2016 C2 mediante Resolución de Directorio N°504 y 510/17.
El Fondo Fiduciario de Promoción de la Industria del Software (FONSOFT) anuncia los resultados del proceso de evaluación del llamado ANR Capacitación Fonsoft mediante la resolución nº 499/17 del Directorio de la Agencia.
El Fondo Fiduciario de Promoción de la Industria del Software (FONSOFT) anuncia el resultado del proceso de evaluación para las convocatorias ANR Empresa Joven FONSOFT 2016 C1 y C2 mediante Resolución de Directorio N°503,508 y 509/17.
El Fondo Fiduciario de Promoción de la Industria del Software (FONSOFT) anuncia los resultados del proceso de reconsideración y evaluación para la convocatoria ANR FONSOFT 2015 C2 y 2016 C1 y c2 mediante Resolución de Directorio N°494,500,501,502,511 y 512/17.
El Fondo Fiduciario de Promoción de la Industria del Software (FONSOFT) anuncia el resultados del proceso de reconsideracion para la convocatoria Becas Jóvenes Profesionales TIC 2016 mediante Resolución de Directorio N°498 y 505/17.
Seminal plasma proteins modify the distribution of sperm subpopulations in cryopreserved semen of rams with lesser fertility
Ledesma, Alba; Zalazar, Lucia; Fernández Alegre, Estela; Hozbor, Federico Andrés; Cesari, Andreina; Martínez Pastor, Felipe
Any physiological mechanism involved in sperm selection and semen improvement has effects on heterogeneous sperm populations. This is mainly due to the fact that sperm populations within a single ejaculate have considerable heterogeneity for many variables, such as motility which is meaningful in terms of understanding how some sperm cells possess fertility advantages as compared with other cells. In the present research, initially there was a multivariate and clustering analysis used to assess sperm motility data from cryopreserved ram semen to identify subpopulations and compare the distribution of these clusters between rams with lesser and greater fertility. There were four classifications made of sperm subpopulations (clusters): CL1 fast/linear/progressive sperm; CL2 fast/non-linear sperm; CL3 very fast/linear sperm with vigorous beating and CL4 slow/non-linear sperm. Rams with greater fertility had a lesser proportion of sperm considered as “hyperactivated” (CL2) and a greater proportion of slow and non-linear sperm (CL4) than sperm of rams with lesser fertility. In addition, the effects were assessed for the capacity of seminal plasma (SP) and interacting SP proteins (iSPP) that were present during different seasons of the year to improve the distribution of sperm within subpopulations of semen from rams with lesser fertility. The iSPP and SP were obtained by artificial vagina (AV) and electroejaculation (EE) during breeding and non-breeding seasons and added to thawed semen. All the aggregates had a significant effect on the distribution of sperm subpopulations and effects differed among seasons of the year and depending on collection method used. Even though, future studies are needed to assess the contribution of each subpopulation on ram sperm fertility, it is important that a multivariate analysis be used to evaluate the effect of a treatment on sperm quality variables.
La Agencia Nacional de Promoción Científica y Tecnológica (ANPCYT), a través del Fondo para la Investigación Científica y Tecnológica (FONCyT) llama, en forma conjunta con la Universidad Pedagógica Provincial (UNIPE), a la presentación de proyectos de Investigación Científica y Tecnológica para la adjudicación de subsidios a grupos de investigadores formados y activos de la Universidad Pedagógica Provincial orientados a áreas de interés común con el co-financiador.
El titular de la Agencia Nacional de Promoción Científica y Tecnológica realizó dos charlas de difusión ante referentes del sector privado y público de la localidad chubutense.
Autoridades del organismo internacional y del Fondo Argentino Sectorial visitaron la compañía biotecnológica del Grupo Insud.
El Fondo Tecnológico Argentino (FONTAR) anuncia que se ha prorrogado las fechas límites de la convocatoria ANR 4800 2017 C2
El Fondo Tecnológico Argentino (FONTAR) anuncia que se ha prorrogado las fechas límites de la convocatoria ANR Social 2017 C2
El Fondo Tecnológico Argentino (FONTAR) anuncia los resultados del proceso de reconsideración para la convocatoria ANR 3500 2016 C3 mediante Resolución de Directorio N°491/17.
La Agencia Nacional de Promoción Científica y Tecnológica y Grupo Arcor anuncian los ganadores de la V edición del Premio Arcor a la Innovación.
El Fondo para la Investigación Científica y Tecnológica (FONCyT) anuncia los resultados de adjudicación de la ventanilla PID mediante la Resolución N° 451/17.
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