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Using both cross-sectional and longitudinal data spanning a decade, this article analyzes how dietary behavior of household children and adults (N = 576 households) was affected by the Stanford Five-City Project (FCP). Tests of a three-part, cumulative model of bidirectional influences within the family, which conceptualizes household members as sources of influence on each other and subject to influence by an external agent, were supported. Children and adults were influenced by both each other and the FCP campaign in changing and maintaining health behaviors. This article demonstrates that public health campaigns can be made more effective if they conceptualize both children and adults as potential sources of influence. The long-term effectiveness of such efforts can be enhanced by encouraging families, as opposed to individuals, to change health behaviors.  相似文献   
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Suicides among older adults in the United States and Canada in the last decade have accounted for an increasing share of all suicides. In both countries the use of firearms among older adults has steadily increased. Despite these trends, little is known about the extent to which crisis centers are prepared to prevent elder suicide. A survey of AAS-listed crisis prevention centers examined the training, knowledge, and current practices relevant to elder suicide among personnel in 321 crisis prevention centers in both countries. Results revealed insufficient training, a lack of familiarity with recent suicide trends, and limited outreach to older adults.  相似文献   
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In Experiment 1, rats were trained on a discrimination between rubber- and sandpaper-covered arms of a maze after one group had been pre-exposed to these intra-maze cues. Pre-exposure facilitated subsequent discrimination learning, unless the discrimination was made easier by adding further discriminative stimuli, when it now significantly retarded learning. In Experiment 2, rats were trained on an extra-maze spatial discrimination, again after one group, but not another, had been pre-exposed to the extra-maze landmarks. Here too, pre-exposure facilitated subsequent discrimination learning, unless the discrimination was made substantially easier by arranging that the two arms between which rats had to choose were always separated by 135°. The results of both experiments can be explained by supposing that perceptual learning depends on the presence of features common to S+ and S-.  相似文献   
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