3,345,276 research outputs found
Stroke treatment academic industry roundtable recommendations for individual data pooling analyses in stroke
Pooled analysis of individual patient data from stroke trials can deliver more precise estimates of treatment effect, enhance power to examine prespecified subgroups, and facilitate exploration of treatment-modifying influences. Analysis plans should be declared, and preferably published, before trial results are known. For pooling trials that used diverse analytic approaches, an ordinal analysis is favored, with justification for considering deaths and severe disability jointly. Because trial pooling is an incremental process, analyses should follow a sequential approach, with statistical adjustment for iterations. Updated analyses should be published when revised conclusions have a clinical implication. However, caution is recommended in declaring pooled findings that may prejudice ongoing trials, unless clinical implications are compelling. All contributing trial teams should contribute to leadership, data verification, and authorship of pooled analyses. Development work is needed to enable reliable inferences to be drawn about individual drug or device effects that contribute to a pooled analysis, versus a class effect, if the treatment strategy combines ≥2 such drugs or devices. Despite the practical challenges, pooled analyses are powerful and essential tools in interpreting clinical trial findings and advancing clinical care
If you don’t snooze you lose health and gain weight: evidence from a regression discontinuity design
Sleep deprivation is increasingly recognized as a public health challenge. While several studies provided evidence of important associations between sleep deprivation and health outcomes, it is less clear whether sleep deprivation is a cause or a marker of poor health. This paper studies the causal effects of sleep on health status and obesity exploiting the relationship between sunset light and circadian rhythms and using time-zone boundaries as an exogenous source of variation in sleep duration and quality. Using data from the American Time Use Survey, we show that individuals living in counties on the eastern side of a time zone boundary go to bed later and sleep less than individuals on the opposite side of the time zone boundary. These findings are driven by individuals whose biological schedules and time use are constrained by social schedules (i.e., work schedules, school starting times). Exploiting these discontinuities, we find evidence that sleep deprivation increases the likelihood of reporting poor health status and the incidence of obesity. Our results suggest that the increase in obesity is explained by both changes in eating behavior and a decrease in physical activity
Una cartografía de las desigualdades y los conflictos desde los sistema mundo
Los mapas siempre nos ayudan a tener una visión, si no exacta, por lo menos general, de los fenómenos; el libro reseñado es eso, un mapa particular de las crisis globales vistas desde la investigación para la paz y la teoría de los sistema mundo, como acercamientos teórico-metodológicos a las desigualdades, los con ictos y las violencias que se producen en estas nuevas relaciones NorteSur. Sin embargo, es una cartografía que analiza las crisis de los países centrales, que los hacen transitar a las fronteras de lo periférico y sus consecuencias para los países considerados periféricos
Pancharatnam-Berry phase in condensate of indirect excitons
We report on the observation of the Pancharatnam-Berry phase in a condensate
of indirect excitons (IXs) in a GaAs coupled quantum well structure. The
Pancharatnam-Berry phase leads to phase shifts of interference fringes in IX
interference patterns. Correlations are found between the phase shifts,
polarization pattern of IX emission, and onset of IX spontaneous coherence. The
Pancharatnam-Berry phase is acquired due to coherent spin precession in IX
condensate. The effect of the Pancharatnam-Berry phase on the IX phase pattern
is described in terms of an associated momentum.Comment: 6 pages, 5 figures + 2 pages supplemental material, 3 supplemental
figure
La violencia mediática: un estudio de caso
El presente trabajo tiene como objetivo plantear cómo se representa la violencia en los medios de comunicación, para ese efecto se realiza un análisis de notas periodísticas referentes a la realidad del Estado de México, en los meses de junio a agosto de 2005 -periodo de actividad electoral-, a partir de dos periódicos, uno netamente lo cal (El Sol de Toluca) y otro de corte nacional, en su sección "Estado" (Reforma). Para lograr dicho objetivo se ocupó como metodología el análisis del discurso, específicamente en su variante de las macroestructuras semánticas (resumen, titular y encabezamiento de la nota periodística), sobre las cuales se efectúa un análisis del tipo y forma de la argumentación; es decir, las macroestructuras entendidas como ese conjunto jerárquico de temas que conforman la estructura temática del texto, permitió centrar el análisis en el problema de la violencia, identificar los elementos dominantes, examinar la gama de diferencias y diversidad de estilos, así como la diversidad de discursos que la prensa construye en torno a la violencia. Describir los discursos, en gen eral, y los de la violencia, en particular, nos posibilita comprender de qué manera la prensa, en tanto institución mediática, tiene un papel importante en la construcción de la realidad
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