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ABSTRACT: In an ecological study of the distribution of self-injury in London, Canada, the authors found that self-injury occurred more frequently in the central areas of the city. Multivariate analysis revealed that living arrangements, such as high density of housing and single-person households, are closely associated with inflated rates on self-injury. Low socio-economic status is also related to self-injury but neither family status nor mobility are significant predictors. Ecological relationships such as these suggest directions for future research on individuals and may also be of direct use to planners who wish to locate treatment services advantageously.  相似文献   
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W e conducted a case‐control study of the association between nearly lethal suicide attempts and facets of alcohol consumption; namely, drinking frequency, drinking quantity, binge drinking, alcoholism, drinking within 3 hours of suicide attempt, and age began drinking. Subjects were 13–34 years of age. In bivariable analyses, all measures were associated with nearly lethal suicide attempts. Odds ratios ranged from 2.4 for alcoholism to 7.0 for drinking within 3 hours of attempt. All exposure variables except age began drinking exhibited a J‐shaped relationship between alcohol exposure and nearly lethal suicide attempt. After controlling for potential confounders and other measures of alcohol exposure, drinking within 3 hours of attempt remained most strongly (odds ratios > 6) associated. Alcoholism remained significantly associated in most models, but at lower strength.  相似文献   
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Animal Cognition - The ability to recognize conspecifics by their acoustic signals is of crucial importance to social animals, especially where visibility is limited, because it allows for...  相似文献   
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The ability to successfully search for an invisibly displaced object is frequently assumed to relate to the emergence of mental representation at around 2 years of age. However, little is known about what is actually being measured in the typical “stage 6” object permanence search task. Two studies examined the effects of task factors and practice on invisible displacements and systematic search tasks to show that simple variations in ways of hiding an object change the child's ability to find it. Experiment 1 compared two common methods of presenting invisible displacements items to 36 children, approximately 2 years of age. One task was significantly easier than the other, despite the fact that they contained identical items that varied only in their order of presentation. Experiment 2 tested the effects of short-term practice on 18- and 24-month-olds' success on invisible displacements trials and on two systematic search tasks. Results indicate that too little practice inhibited performance in 18-month-olds, but that practice beyond an optimum level did not further affect their scores. In contrast, 24-month-olds continued to benefit from increased practice until they reached the maximum possible score. The findings are interpreted to mean that invisible displacements tasks may require only sensorimotor search strategies rather than representation. The findings also have implications for (a) research that attempts to relate object permanence to other variables and (b) programs that use object permanence as an assessment or screening measure.  相似文献   
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