939 resultados para meta-data


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The ascertainment and analysis of adverse reactions to investigational agents presents a significant challenge because of the infrequency of these events, their subjective nature and the low priority of safety evaluations in many clinical trials. A one year review of antibiotic trials published in medical journals demonstrates the lack of standards in identifying and reporting these potentially fatal conditions. This review also illustrates the low probability of observing and detecting rare events in typical clinical trials which include fewer than 300 subjects. Uniform standards for ascertainment and reporting are suggested which include operational definitions of study subjects. Meta-analysis of selected antibiotic trials using multivariate regression analysis indicates that meaningful conclusions may be drawn from data from multiple studies which are pooled in a scientifically rigorous manner. ^

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Objetivos: a. Determinar la eficacia de la actividad física en la reducción del riesgo de enfermedades cardiovasculares; b. Analizar los cambios relativos en los niveles de riesgo a padecer enfermedades cardiovasculares de acuerdo a diferentes intensidades (baja-moderada) de actividad física. Metodología: Se realizó un Meta-análisisde los estudios encontrados en la base de datos PUBMED. Se calculó el tamaño del efecto medio y se aplicó el test de Eggerpara descartar un posible sesgo de publicación. Al detectarse heterogeneidad, se procedió a realizar un análisis de las variables moderadoras. Resultados: Se obtuvo un tamaño del efecto medio de 0.762 (0.678-0857; 95 por ciento IC). El test de Egger arrojó un p-valor de 0.67 (I.C. 0.95), de manera tal que se confirmó la ausencia de sesgo de publicación. El análisis moderador determinó que los años de seguimiento (p=0.000; 95 por ciento IC) y los países de estudio (p=0.0096; 95 por ciento IC) son significativos. Conclusión: Se puede concluir en que la práctica de actividad física a intensidades moderadas ofrece un efecto protector sobre los individuos que la realizan disminuyendo el riesgo a padecer enfermedades cardiovasculares

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Objetivos: a. Determinar la eficacia de la actividad física en la reducción del riesgo de enfermedades cardiovasculares; b. Analizar los cambios relativos en los niveles de riesgo a padecer enfermedades cardiovasculares de acuerdo a diferentes intensidades (baja-moderada) de actividad física. Metodología: Se realizó un Meta-análisisde los estudios encontrados en la base de datos PUBMED. Se calculó el tamaño del efecto medio y se aplicó el test de Eggerpara descartar un posible sesgo de publicación. Al detectarse heterogeneidad, se procedió a realizar un análisis de las variables moderadoras. Resultados: Se obtuvo un tamaño del efecto medio de 0.762 (0.678-0857; 95 por ciento IC). El test de Egger arrojó un p-valor de 0.67 (I.C. 0.95), de manera tal que se confirmó la ausencia de sesgo de publicación. El análisis moderador determinó que los años de seguimiento (p=0.000; 95 por ciento IC) y los países de estudio (p=0.0096; 95 por ciento IC) son significativos. Conclusión: Se puede concluir en que la práctica de actividad física a intensidades moderadas ofrece un efecto protector sobre los individuos que la realizan disminuyendo el riesgo a padecer enfermedades cardiovasculares

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Objetivos: a. Determinar la eficacia de la actividad física en la reducción del riesgo de enfermedades cardiovasculares; b. Analizar los cambios relativos en los niveles de riesgo a padecer enfermedades cardiovasculares de acuerdo a diferentes intensidades (baja-moderada) de actividad física. Metodología: Se realizó un Meta-análisisde los estudios encontrados en la base de datos PUBMED. Se calculó el tamaño del efecto medio y se aplicó el test de Eggerpara descartar un posible sesgo de publicación. Al detectarse heterogeneidad, se procedió a realizar un análisis de las variables moderadoras. Resultados: Se obtuvo un tamaño del efecto medio de 0.762 (0.678-0857; 95 por ciento IC). El test de Egger arrojó un p-valor de 0.67 (I.C. 0.95), de manera tal que se confirmó la ausencia de sesgo de publicación. El análisis moderador determinó que los años de seguimiento (p=0.000; 95 por ciento IC) y los países de estudio (p=0.0096; 95 por ciento IC) son significativos. Conclusión: Se puede concluir en que la práctica de actividad física a intensidades moderadas ofrece un efecto protector sobre los individuos que la realizan disminuyendo el riesgo a padecer enfermedades cardiovasculares

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Two highly active mud volcanoes located in 990-1,265 m water depths were mapped on the northern Egyptian continental slope during the BIONIL expedition of R/V Meteor in October 2006. High-resolution swath bathymetry and backscatter imagery were acquired with an autonomous underwater vehicle (AUV)-mounted multibeam echosounder, operating at a frequency of 200 kHz. Data allowed for the construction of ~1 m pixel bathymetry and backscatter maps. The newly produced maps provide details of the seabed morphology and texture, and insights into the formation of the two mud volcanoes. They also contain key indicators on the distribution of seepage and its tectonic control. The acquisition of high-resolution seafloor bathymetry and acoustic imagery maps with an AUV-mounted multibeam echosounder fills the gap in spatial scale between conventional multibeam data collected from a surface vessel and in situ video observations made from a manned submersible or a remotely operating vehicle.

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As a result of the variscan collision, several allochtonous complexes were emplaced on the Iberian margin in Devonian times, among them the Cabo Ortegal Complex comprising the Moeche ophiolitic sequence. Copper has been won from several mines (Piquitos I & II, Barqueira, Maruxa) from disseminated ores and thin massive sulphide layers in the Moeche Unit, a strongly deformed meta-volcanic sequence comprising mainly quartz-chlorite schists and mylonites, which defines the top of the ophiolite. The ores were metamorphosed and strongly deformed under brittle conditions (for pyrite), but their textures are often apparently post-deformational, due to very common solution-transfer processes; they are composed mostly of pyrite and chalcopyrite, with minor sphalerite, pyrrhotite, etc., and with traces of native gold and PGE. The geology, mineralogy, and geochemistry of the orebodies relate closely to VMS of the Cu-Zn (Cyprus) type. Fluid inclusion studies allowed an estimation of metamorphic conditions at pressures of 2/2’5 kb and T 325/350ºC. New determinations using the chlorite geothermometer yield temperatures around 320 ºC, corresponding to pressures near 2 kb according to the isochores deduced from the fluid inclusion study, although in the Barqueira mine higher temperatures, up to 350 ºC, are found, corresponding to presssures up to 2’5 kb. Pb isotopic compositions of pyrite point to a double source of Pb, i.e. a main mantle and a subordinate crustal source. The values for 87SR/86Sr in pyrite support this interpretation, but some results suggest later mobilization in an open system, corresponding to solution-transfer. Age determinations of pyrite deduced from the Pb isotope uranogenic graph, ≈ 480 Ma, do not fit with the metamorphic ages published for the Moeche Unit, and might point to the age of Pb extraction from the mantle.

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Abstract interpretation-based data-flow analysis of logic programs is at this point relatively well understood from the point of view of general frameworks and abstract domains. On the other hand, comparatively little attention has been given to the problems which arise when analysis of a full, practical dialect of the Prolog language is attempted, and only few solutions to these problems have been proposed to date. Such problems relate to dealing correctly with all builtins, including meta-logical and extra-logical predicates, with dynamic predicates (where the program is modified during execution), and with the absence of certain program text during compilation. Existing proposals for dealing with such issues generally restrict in one way or another the classes of programs which can be analyzed if the information from analysis is to be used for program optimization. This paper attempts to fill this gap by considering a full dialect of Prolog, essentially following the recently proposed ISO standard, pointing out the problems that may arise in the analysis of such a dialect, and proposing a combination of known and novel solutions that together allow the correct analysis of arbitrary programs using the full power of the language.

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Colombia is one of the largest per capita mercury polluters in the world as a consequence of its artisanal gold mining activities. The severity of this problem in terms of potential health effects was evaluated by means of a probabilistic risk assessment carried out in the twelve departments (or provinces) in Colombia with the largest gold production. The two exposure pathways included in the risk assessment were inhalation of elemental Hg vapors and ingestion of fish contaminated with methyl mercury. Exposure parameters for the adult population (especially rates of fish consumption) were obtained from nation-wide surveys and concentrations of Hg in air and of methyl-mercury in fish were gathered from previous scientific studies. Fish consumption varied between departments and ranged from 0 to 0.3 kg d?1. Average concentrations of total mercury in fish (70 data) ranged from 0.026 to 3.3 lg g?1. A total of 550 individual measurements of Hg in workshop air (ranging from menor queDL to 1 mg m?3) and 261 measurements of Hg in outdoor air (ranging from menor queDL to 0.652 mg m?3) were used to generate the probability distributions used as concentration terms in the calculation of risk. All but two of the distributions of Hazard Quotients (HQ) associated with ingestion of Hg-contaminated fish for the twelve regions evaluated presented median values higher than the threshold value of 1 and the 95th percentiles ranged from 4 to 90. In the case of exposure to Hg vapors, minimum values of HQ for the general population exceeded 1 in all the towns included in this study, and the HQs for miner-smelters burning the amalgam is two orders of magnitude higher, reaching values of 200 for the 95th percentile. Even acknowledging the conservative assumptions included in the risk assessment and the uncertainties associated with it, its results clearly reveal the exorbitant levels of risk endured not only by miner-smelters but also by the general population of artisanal gold mining communities in Colombia.

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La evaluación de las prestaciones de las embarcaciones a vela ha constituido un objetivo para ingenieros navales y marinos desde los principios de la historia de la navegación. El conocimiento acerca de estas prestaciones, ha crecido desde la identificación de los factores clave relacionados con ellas(eslora, estabilidad, desplazamiento y superficie vélica), a una comprensión más completa de las complejas fuerzas y acoplamientos involucrados en el equilibrio. Junto con este conocimiento, la aparición de los ordenadores ha hecho posible llevar a cabo estas tareas de una forma sistemática. Esto incluye el cálculo detallado de fuerzas, pero también, el uso de estas fuerzas junto con la descripción de una embarcación a vela para la predicción de su comportamiento y, finalmente, sus prestaciones. Esta investigación tiene como objetivo proporcionar una definición global y abierta de un conjunto de modelos y reglas para describir y analizar este comportamiento. Esto se lleva a cabo sin aplicar restricciones en cuanto al tipo de barco o cálculo, sino de una forma generalizada, de modo que sea posible resolver cualquier situación, tanto estacionaria como en el dominio del tiempo. Para ello se comienza con una definición básica de los factores que condicionan el comportamiento de una embarcación a vela. A continuación se proporciona una metodología para gestionar el uso de datos de diferentes orígenes para el cálculo de fuerzas, siempre con el la solución del problema como objetivo. Esta última parte se plasma en un programa de ordenador, PASim, cuyo propósito es evaluar las prestaciones de diferentes ti pos de embarcaciones a vela en un amplio rango de condiciones. Varios ejemplos presentan diferentes usos de PASim con el objetivo de ilustrar algunos de los aspectos discutidos a lo largo de la definición del problema y su solución . Finalmente, se presenta una estructura global de cara a proporcionar una representación virtual de la embarcación real, en la cual, no solo e l comportamiento sino también su manejo, son cercanos a la experiencia de los navegantes en el mundo real. Esta estructura global se propone como el núcleo (un motor de software) de un simulador físico para el que se proporciona una especificación básica. ABSTRACT The assessment of the performance of sailing yachts, and ships in general, has been an objective for naval architects and sailors since the beginning of the history of navigation. The knowledge has grown from identifying the key factors that influence performance(length, stability, displacement and sail area), to a much more complete understanding of the complex forces and couplings involved in the equilibrium. Along with this knowledge, the advent of computers has made it possible to perform the associated tasks in a systematic way. This includes the detailed calculation of forces, but also the use of those forces, along with the description of a sailing yacht, to predict its behavior, and ultimately, its performance. The aim of this investigation is to provide a global and open definition of a set of models and rules to describe and analyze the behavior of a sailing yacht. This is done without applying any restriction to the type of yacht or calculation, but rather in a generalized way, capable of solving any possible situation, whether it is in a steady state or in the time domain. First, the basic definition of the factors that condition the behavior of a sailing yacht is given. Then, a methodology is provided to assist with the use of data from different origins for the calculation of forces, always aiming towards the solution of the problem. This last part is implemented as a computational tool, PASim, intended to assess the performance of different types of sailing yachts in a wide range of conditions. Several examples then present different uses of PASim, as a way to illustrate some of the aspects discussed throughout the definition of the problem and its solution. Finally, a global structure is presented to provide a general virtual representation of the real yacht, in which not only the behavior, but also its handling is close to the experience of the sailors in the real world. This global structure is proposed as the core (a software engine) of a physical yacht simulator, for which a basic specification is provided.

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Purpose: Breast cancer is the most frequently diagnosed cancer among women worldwide. While undergoing chemotherapy treatment for breast cancer, patients often report experiencing "chemobrain." Previous literature reports correlations between psychological distress and these perceived cognitive problems. The aim of the present study was to examine the strength of the association between affective disturbance and subjective cognitive dysfunction.Methods: This study included a meta-analysis of the literature reporting a correlation between mood and subjective cognitive dysfunction. Eight studies with 1344 breast cancer patients treated with chemotherapy were selected based on stringent study inclusion criteria. Studies reporting a correlation coefficient between mood and subjective cognitive dysfunction were included.Results: In these data, there was no significant correlation between affective disturbance and subjective cognitive dysfunction. A random effects model yielded an overall weighted mean effect size of 0.12.Conclusion: Although this meta-analysis did not confirm the correlation between mood and subjective cognitive dysfunction, there was a clear association between these factors in the original disaggregated analyses, and they are clearly impactful from the time of diagnosis through long-term after care. The clinical implications of the present study and future directions for research are discussed.

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Image Based Visual Servoing (IBVS) is a robotic control scheme based on vision. This scheme uses only the visual information obtained from a camera to guide a robot from any robot pose to a desired one. However, IBVS requires the estimation of different parameters that cannot be obtained directly from the image. These parameters range from the intrinsic camera parameters (which can be obtained from a previous camera calibration), to the measured distance on the optical axis between the camera and visual features, it is the depth. This paper presents a comparative study of the performance of D-IBVS estimating the depth from three different ways using a low cost RGB-D sensor like Kinect. The visual servoing system has been developed over ROS (Robot Operating System), which is a meta-operating system for robots. The experiments prove that the computation of the depth value for each visual feature improves the system performance.

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A meta-analysis of team building interventions in sport was completed. Seventeen studies containing 180 effect sizes were retrieved. The overall effect (Hedges g) was .427. Analyses of possible moderator variables showed the largest effect sizes were in interventions where: (a) non-experimental designs were used (g=.474); (b) the data were unpublished (g=.539); (c) goal setting only was used (g=.714); (d) the coach/manager directed the delivery (g=.446); and (e) the teams were at the university level (g=.482). Finally, team building had the greatest influence on cognitions (g=.799

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Schizophrenia is a common disorder with high heritability and a 10-fold increase in risk to siblings of probands. Replication has been inconsistent for reports of significant genetic linkage. To assess evidence for linkage across studies, rank-based genome scan meta-analysis (GSMA) was applied to data from 20 schizophrenia genome scans. Each marker for each scan was assigned to 1 of 120 30-cM bins, with the bins ranked by linkage scores (1 = most significant) and the ranks averaged across studies (R-avg) and then weighted for sample size (rootN[affected cases]). A permutation test was used to compute the probability of observing, by chance, each bin's average rank (P-AvgRnk) or of observing it for a bin with the same place (first, second, etc.) in the order of average ranks in each permutation (P-ord). The GSMA produced significant genomewide evidence for linkage on chromosome 2q (P-AvgRnk

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Based on the epidemiological finding that individuals with schizophrenia tend to be born in winter/spring when compared to the general population, we examined (1) the strength and timing of this effect in Northern Hemisphere sites, and (2) the correlation between the season of birth effect size and latitude. Studies were located via electronic data sources, published citations, and letters to authors. Inclusion criteria were that studies specify the diagnostic criteria used, that studies specify the counts of schizophrenia and general population births for each month, and that subjects and the general population be drawn from the same birth years and catchment area. We extracted data from eight studies based on 126,196 patients with schizophrenia and 86,605,807 general population births and drawn from 27 Northern Hemisphere sites. Comparing winter/spring versus summer/autumn births, we found a significant excess for winter/spring births (pooled odds ratio = 1.07; 95% confidence interval 1.05, 1.08; population attributable risk = 3.3%). There was a small but significant positive correlation between the odds ratios for the season of birth comparison and latitude (r = 0.271, p < 0.005). Furthermore, the shape of the seasonality in schizophrenia births varied by latitude band. These variations may encourage researchers to generate candidate seasonally fluctuating exposures.