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991.
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993.
This paper presents the results of an ecological analysis of the relationship between infant mortality and economic status in a metropolitan aggregate comprised of seven of the larger cities in Ohio during the three years centering on the 1990 census. Using a summary income score derived for the census tract of mother's usual residence, the census tracts in the seven metropolitan centers were divided into broad income groupings and three-year average infant mortality rates were computed for each area, by age, sex, race, and selected causes of death. The most important conclusion to be drawn from the data is that in spite of some remarkable declines in overall levels of infant mortality during the past few decades, there continues to be a very clear and pronounced inverse association between income status and infant mortality. The general inverse association is observed for both sexes, for whites and nonwhites, and for all major causes of infant death. At the same time, the data reveal notable differences in the magnitude of the relationship by sex, and especially by age at death, race, and cause of death. Explanations of these differences are suggested, and a conclusion notes some of the difficulties encountered in developing programs aimed at closing the infant mortality gap between the richest and poorest segments of the society.This is an expanded version of a paper presented at the annual meetings of the Eastern Sociological Society in Baltimore, Maryland (March 17–20, 1994).  相似文献   
994.
Policy-makers in both Mexico and the U.S. reacted to the economic crisis which began in Mexico in December, 1994 as if it were a problem of short-run financial liquidity. The argument presented in this article is that Mexico's current crisis has its origins in long-standing, fundamental problems of the Mexican economy. These long-run problems include: massive external debt, a severely skewed income distribution, inadequate job creation, low productivity per worker and lack of investment in infrastructure. The short-run policy response will not address the long-run problems.  相似文献   
995.
Most real-world shapes and images are characterized by high variability- they are not rigid, like crystals, for example—but they are strongly structured. Therefore, a fundamental task in the understanding and analysis of such image ensembles is the construction of models that incorporate both variability and structure in a mathematically precise way. The global shape models introduced in Grenander's general pattern theory are intended to do this. In this paper, we describe the representation of two-dimensional mitochondria and membranes in electron microscope photographs, and three-dimensional amoebae in optical sectioning microscopy. There are three kinds of variability to all of these patterns, which these representations accommodate. The first is the variability in shape and viewing orientation. For this, the typical structure is represented via linear, circular and spherical templates, with the variability accomodated via the application of transformations applied to the templates. The transformations form groups: scale, rotation and translation. They are locally applied throughout the continuum and of high dimension. The second is the textural variability; the inside and outside of these basic shapes are subject to random variation, as well as sensor noise. For this, statistical sensor models and Markov random field texture models are used to connect the constituent structures of the shapes to the measured data. The third variability type is associated with the fact that each scene is made up of a variable number of shapes; this number is not assumed to be known a priori. Each scene has a variable number of parameters encoding the transformations of the templates appropriate for that scene. For this, a single posterior distribution is defined over the countable union of spaces representing models of varying numbers of shapes. Bayesian inference is performed via computation of the conditional expectation of the parametrically defined shapes under the posterior. These conditional mean estimates are generated using jump-diffusion processes. Results for membranes, mitochondria and amoebae are shown.  相似文献   
996.
Abstract Major shifts in the terms of the social contract between society and land grant universities have implications for the research, teaching, and extension agenda of rural sociology. By tracing the legislative, academic, and social context of these changes, one can understand the evolving process, the forces of change, and the necessity for new organizational strategies to respond to society's needs. Better networking with constituencies and use of advisory councils would tie the discipline closer to these needs. The identification of substantive needs are a product of such interaction and reflect new opportunities for rural sociology to provide leadership for human and community development programs.  相似文献   
997.
998.
The effects of maternal expressiveness and children's gender on children's nonverbal expressiveness were assessed in two settings. In the laboratory, 30 boys and 30 girls of kindergarten age were unobtrusively videotaped while talking about happy, sad, and fearful experiences and while experiencing three social situations designed to elicit happy, disappointed, and apprehensive feelings. Videotapes were rated for emotion expression, using global ratings and EMFACS codes. In school, teachers rated these children's expression of four discrete emotions. In both the laboratory and school settings children were more positively expressive than negatively so, and positive and negative expressiveness were unrelated. In the laboratory children's positive expressiveness was consistent across the three social situations, but negative expressiveness varied across affective context. In both settings, children of low-expressive mothers were more positively expressive than children of high-expressive mothers, who tended to be more negatively expressive than children of low-expressive mothers. The difference in negative expression appeared most striking for anger. Gender was not predictive of children's expressiveness in either setting  相似文献   
999.
1000.
This paper presents a method of estimating long-term exposures to point source emissions. The method consists of a Monte Carlo exposure model (PSEM or Point Source Exposure Model) that combines data on population mobility and mortality with information on daily activity patterns. The approach behind the model can be applied to a wide variety of exposure scenarios. In this paper, PSEM is used to characterize the range and distribution of lifetime equivalent doses received by inhalation of air contaminated by the emissions of a point source. The output of the model provides quantitative information on the dose, age, and gender of highly exposed individuals. The model is then used in an example risk assessment. Finally, future uses of the model's approach are discussed.  相似文献   
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