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151.
The present study drew on four competing theoretical perspectives to examine the relationship between family structure and juvenile delinquency. Using data from the Add Health Study, the authors examined nonserious and serious delinquent behavior across youth from different types of households and also considered how the association between family structure and delinquency might be conditioned by family processes and economic factors. Results from negative binomial regression analyses indicated that, in general, type of household was not a significant predictor of nonserious or serious delinquency. Rather, maternal attachment emerged as the most important determinant of delinquent behavior among youth from all family types. The results are discussed within the context of Hirschi's original interpretation of social control theory and future directions for research are suggested.  相似文献   
152.
Postmortem examination of a former professional basketball player revealed an abnormal heart, most notably a single coronary artery. The literature on single coronary arteries is briefly reviewed, and the possible mechanism which caused the patient's condition is considered. This case is particularly unusual because of the patient's profession, which is so physically demanding.  相似文献   
153.
The fingernail ridge patterns of a pair of identical twins were compared to each other, their parents, and an unrelated subject. The patterns of the twins' nails showed regions of strong similarity but were distinguishable from one another. Fewer similarities were found when comparing the nails to those of the parents and the unrelated control. The twins were shown to be monozygotic by means of DNA profiling. This therefore represents the first demonstration of unique fingernail ridge patterns in subjects shown conclusively to be identical twins. When the fingernail ridge patterns were examined with a scanning electron microscope, the backscattered electron (BEI) images were found to have superior contrast when compared to the secondary electron (SEI) images.  相似文献   
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Using merged administrative data from welfare reform evaluations in three states, we estimate the effects of child care subsidy use on the length of time it takes for a welfare applicant to move into substantial employment. Findings show that the use of a child care subsidy during an unemployed or marginally employed spell of welfare receipt is associated with between a 0.6 and 1.7 quarter (or 11% to 34%) reduction in the time to substantial employment in two of the three state samples. The positive influence of subsidy use on transitions to substantial employment is strongest for those welfare applicants with the lowest earnings who are mixing welfare and work prior to subsidy receipt.  相似文献   
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This paper applies the poliheuristic theory of foreign policy decision making to non-democratic states. Poliheuristic theory asserts that state leaders assign primary importance to their political survival; however, the meaning of "the political" varies dramatically from country to country. Furthermore, the types of actors who hold leaders politically accountable also vary between countries. Consequently, leaders often pursue vastly different means of ensuring their political survival. The author uses the common distinction between single-party, military, and personalist autocracies to show that apparently arbitrary differences in autocratic leaders' political concerns actually vary in systematic and potentially predictable ways. Because this argument is generalized to non-democratic states as a whole, it has important implications for the ways in which democratic states craft their policies toward autocracies.  相似文献   
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