399 research outputs found
A segmented period-luminosity relation for nearby extragalactic Scuti stars
The period-luminosity relations (PLR) of Milky Way Scuti (
Sct) stars have been described to the present day by a linear relation.
However, when studying extragalactic systems such as the Magellanic Clouds and
several dwarf galaxies, we notice for the first time a non-linear behaviour in
the PLR of Sct stars. Using the largest sample of
extragalactic Sct stars from data available in the literature
mainly based on OGLE and SuperMACHO survey in the Large Magellanic Cloud
(LMC) we obtain that the best fit to the period-luminosity () plane is
given by the following piecewise linear relation with a break at (or d) for shorter periods (sp) and longer
periods (lp) than the break-point:
Geometric or depth effects in the LMC, metallicity dependence, or different
pulsation modes are discarded as possible causes of this segmented PLR seen in
extragalactic Sct stars. The origin of the segmented relation at days remains unexplained based on the current data.Comment: 9 pages, 3 figures, 1 table. Accepted for publication into The
Astrophysical Journal Letter
Portable Solar Spectrum Reflectometer for planar and parabolic mirrors in solar thermal energy plants
This contribution presents a new field Solar Spectrum Reflectometer for solar-weighted specular reflectance characterization of planar, spherical or parabolic mirrors. This reflectometer is designed to provide fast and reliable field measurements and to be valid for any type of mirror currently installed in concentrated solar power systems, including parabolic trough, Stirling dish and central receiver power plants. The optical design of the Solar Spectrum Reflectometer, which includes 6 LEDs in the VIS-NIR band, is described, and its tolerance to variations in the geometrical parameters of the mirrors discussed and evaluated. The contribution of diffuse reflection and its impact on the measured reflectance is also calculated for different concentrated solar power systems
Modelling mental healthcare improvement in highly integrated care systems: the case of the Basque Country (Spain)
Currently there is growing interest in providing integrated mental health care between hospital (acute residential care) and community-based services (… and other health systems). Mental health systems are complex due to the high disorder prevalence, socio-economic burden, stigma associated, and high gap of unmet population needs. Mental health can be considered an ecosystem related to, at least, physical health and social services ones. Decision support systems are robust tools for guiding and improving planning and management of health ecosystems by integrating methods like Bayesian networks. These models identify critical variables, domains and constructs and their corresponding causal relationships. The objective of this research is to design an integrated and integral theoretical Bayesian network for guiding mental health planning and management, and in consequence, improving mental health care delivery
Gas monitoring methodology and application to CCS projects as defined by atmospheric and remote sensing survey in the natural analogue of Campo de Calatrava
CO2 capture and storage (CCS) projects are presently developed to reduce the emission of anthropogenic CO2 into the atmosphere. CCS technologies are expected to account for the 20% of the CO2 reduction by 2050. Geophysical, ground deformation and geochemical monitoring have been carried out to detect potential leakage, and, in the event that this occurs, identify and quantify it. This monitoring needs to be developed prior, during and after the injection stage. For a correct interpretation and quantification of the leakage, it is essential to establish a pre-injection characterization (baseline) of the area affected by the CO2 storage at reservoir level as well as at shallow depth, surface and atmosphere, via soil gas measurements. Therefore, the methodological approach is important because it can affect the spatial and temporal variability of this flux and even jeopardize the total value of CO2 in a given area.
In this sense, measurements of CO2 flux were done using portable infrared analyzers (i.e., accumulation chambers) adapted to monitoring the geological storage of CO2, and other measurements of trace gases, e.g. radon isotopes and remote sensing imagery were tested in the natural analogue of Campo de Calatrava (Ciudad Real, Spain) with the aim to apply in CO2 leakage detection; thus, observing a high correlation between CO2 and radon (r=0,858) and detecting some vegetation indices that may be successfully applied for the leakage detection
CREACIÓN DE ÍNDICES DE GESTIÓN DE MATERNIDADES MEDIANTE EL ANÁLISIS DE COMPONENTES PRINCIPALES
Objetivo: Crear índices de gestión de maternidades basados en técnicas estadísticas multivariantes descriptivas. Material y métodos: Durante el mes de enero de 2004 se recopila información de las maternidades públicas de Chile, pertenecientes a Hospitales tipo 1 y 2, que informan de manera desagregada su información obstétrica, correspondiente a sus actividades para el período presupuestario 2001, última información completa y oficial disponible para la totalidad de los Servicios de Salud del país. Se estudiaron variables generadas y/o monitorizadas por el Instituto Nacional de Estadísticas (INE), el Ministerio de Salud (MINSAL), el Ministerio de Hacienda, el Ministerio de Planificación y Cooperación (MIDEPLAN) y el Fondo Nacional de Salud (FONASA). Aplicamos componentes principales (ACP) a partir de la matriz de correlación R. Resultados: Se seleccionaron las tres primeras componentes principales, con un porcentaje acumulado de variabilidad explicada de 63,6%. Conclusiones: La primera componente tiene relación con el promedio de días de estada en las diferentes maternidades, observada como consecuencia de la atención de embarazo, parto y puerperio, abortos, trastornos hipertensivos del embarazo, del parto y del puerperio, complicaciones del embarazo y parto y complicaciones relacionadas principalmente con el puerperio y otras afecciones obstétricas no clasificadas en otra parte y explica el 25,3% de la variabilidad. La segunda componente principal representa la tasa de letalidad por similares causas y explica el 20,1% de la variabilidad. La tercera componente principal explica el 18,2% de la variabilidad y se relaciona con las características de la población a atender y el gasto en el cual incurren los diferentes establecimientos de salu
Experimental Granulomatous Pulmonary Nocardiosis in BALB/C Mice
Pulmonary nocardiosis is a granulomatous disease with high mortality that affects both immunosuppressed and immunocompetent patients. The mechanisms leading to the establishment and progression of the infection are currently unknown. An animal model to study these mechanisms is sorely needed. We report the first in vivo model of granulomatous pulmonary nocardiosis that closely resembles human pathology. BALB/c mice infected intranasally with two different doses of GFP-expressing Nocardia brasiliensis ATCC700358 (NbGFP), develop weight loss and pulmonary granulomas. Mice infected with 109 CFUs progressed towards death within a week while mice infected with 108 CFUs died after five to six months. Histological examination of the lungs revealed that both the higher and lower doses of NbGFP induced granulomas with NbGFP clearly identifiable at the center of the
lesions. Mice exposed to 108 CFUs and subsequently to 109 CFUs were not protected against disease severity but had less granulomas suggesting some degree of protection.
Attempts to identify a cellular target for the infection were unsuccessful but we found that bacterial microcolonies in the suspension used to infect mice were responsible for the establishment of the disease. Small microcolonies of NbGFP, incompatible with nocardial
doubling times starting from unicellular organisms, were identified in the lung as early as six hours after infection. Mice infected with highly purified unicellular preparations of NbGFP did not develop granulomas despite showing weight loss. Finally, intranasal delivery of
nocardial microcolonies was enough for mice to develop granulomas with minimal weight loss. Taken together these results show that Nocardia brasiliensis microcolonies are both necessary and sufficient for the development of granulomatous pulmonary nocardiosis in mice
Escuelas de campo y producción de hortalizas orgánicas en una comunidad Tzotzil
Objective: Evaluate the impact of the transfer of horticultural technology through the Field Schools (ECA) to a group of Tzotziles farmers in Los Altos de Chiapas, Mexico.Design/methodology/approximation: The study was developed with seven families from San Jose del Carmen, San Cristobal de Las Casas, Chiapas. An initial diagnosis was made and during the period 2017-2018 the production of vegetables with the biointensive method was promoted. To evaluate the results, the following variables were determined: cultivated area, yield, diversity of species, stability and destination of production.Results: With the increase of knowledge in the production of crops by the biointensive method, the cultivated area increased by 91%, the production of vegetables in biointensive beds was 10.4 kg m-2. An increase of 86% of the cultivated species was achieved and there was food availability for eight months. 94% of the production was destined for self-consumption.Limitations of the study/implications: The results of this study are considered acceptable, however, it is necessary to continue with the technical support and determine the degree of adoption of technology.
Findings/conclusions: The implementation of the Field Schools model increased the level of knowledge about the method of biointensive cultivation, improving the production and availability of vegetables in San Jose del Carmen, San Cristobal de Las Casas, Chiapas.Objetivo: Evaluar el impacto de la transferencia de tecnología hortícola a través de las Escuelas de Campo (ECA) a un grupo de productores indígenas Tzotziles de Los Altos de Chiapas, México.
Diseño/metodología/aproximación: El estudio se desarrolló con siete familias de San José del Carmen, San Cristóbal de Las Casas, Chiapas. Se realizó un diagnóstico inicial y durante el período 2017-2018 se promovió la producción de hortalizas con el método biointensivo. Para evaluar los resultados, se determinaron las siguientes variables: superficie cultivada, rendimiento, diversidad de especies, estabilidad y destino de la producción.
Resultados: Con el incremento de los conocimientos en la producción de cultivos por el método biointensivo, la superficie cultivada aumento en un 91%, la producción de hortalizas en camas biointensivas fue de 10.4 kg m-2. Se logró un aumento de 86% de las especies cultivadas y hubo disponibilidad de alimentos durante ocho meses. El 94% de la producción se destinó para el autoconsumo.
Limitaciones del estudio/implicaciones: Los resultados de este estudio se consideran aceptables, sin embargo, es necesario continuar con el acompañamiento técnico y determinar el grado de adopción de tecnología.
Conclusiones: La implementación del modelo Escuelas de Campo, incrementó el nivel de conocimientos sobre el método de cultivo biointensivo, mejorando la producción y disponibilidad de hortalizas en San José del Carmen, San Cristóbal de Las Casas, Chiapas
Producción de hortalizas bajo escuelas de campo para la superación de la pobreza
Objective: Increase the diversity of species and yield in vegetable gardens to contribute to overcoming poverty in the town of Tlalcozotitlán, Copalillo, Guerrero.Design/methodology/approximation: The study was carried out with 30 families represented by a member belonging to the organization “El Copalito”, from the town of Tlalcozotitlán, Copalillo, Guerrero. The work was carried out through the Participatory-Action-Research (IAP), which corresponded to the approach and knowledge of the study area; the design and establishment of the plot-school of vegetables, through agroecological management; the development of capacities through the Field Schools (ECAs). The variables were the diversity and production of species in vegetable gardens, sale and economic income for families.Results: On average, the farmers plant 2.3 species of vegetables per family, but there are families that grow up to seven species: chile criollo, tomato, pápalo, miltomate, chipile, quelites and huanzontle, obtaining a total yield of 1 kg m-2 through conventional management, one income per day of 31.20 per day corresponding to 27.74%. There were statistically significant differences in the knowledge and adoption oftechnological innovations by the producers-promoters before and after having received the training courses.Limitations on the study/implications: The result obtained reflects an improvement in family income and contributes to overcoming poverty in the place of study; However, it is necessary to continue spreading agro-ecological technological innovations in order to obtain a better quality product.Findings/Conclusions: The training, technical assistance and dissemination through the model of Field Schools, has influenced so that the technological innovations developed with the project have been accepted and adopted by the producers in their vegetable gardens.Objetivo: Incrementar la diversidad de especies y rendimiento en huertos de hortalizas para contribuir a la superación de la pobreza en la localidad de Tlalcozotitlán, Copalillo, Guerrero.Diseño/metodología/aproximación: El estudio se realizó con 30 familias representadas por un integrante que pertenecen a la organización “El Copalito”, de la localidad de Tlalcozotitlán, Copalillo,Guerrero. El trabajo se llevó a cabo mediante la Investigación-Acción-Participativa (IAP), que correspondió al acercamiento y conocimiento del área de estudio; el diseño y establecimiento de la parcela-escuelade hortalizas, mediante un manejo agroecológico; el desarrollo de capacidades a través de las Escuelas de Campo (ECAs). Las variables fueron la diversidad y producción de especies en huertos de hortalizas,venta e ingresos económicos para las familias.Resultados: En promedio los productores siembran 2.3 especies de hortalizas por familia, pero hay familias que cultivan hasta siete especies: chile criollo, tomate, pápalo, miltomate, chipile, quelites yhuanzontle, obteniendo un rendimiento total de 1 kg m-2 mediante un manejo convencional, un ingreso por día de 31.20 por día correspondiente a 27.74%. Hubo diferencias estadísticamente significativas en el conocimiento y adopción de innovaciones tecnológicas por losproductores-promotores antes y después de haber recibido los cursos de capacitación.Limitaciones del estudio/implicaciones: El resultado obtenido refleja un mejoramiento en el ingreso familiar y contribuye en la superación de la pobreza en el lugar de estudio; sin embargo, se requiere seguir difundiendo las innovaciones tecnológicas agroecológicas para obtener un producto de mejor calidad.Hallazgos/conclusiones: La capacitación, asistencia técnica y la difusión mediante el modelo de Escuelas de Campo, ha incidido para que las innovaciones tecnológicas desarrolladas con el proyecto hayansido aceptado y adoptado por los productores en sus huertos de hortalizas
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