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141.
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
142.
Fred Siegmund 《政策研究评论》1990,9(4):649-663
The paper examines the airline industry ten years after the Airline Deregulation Act of 1978. A brief review of the historical background of regulation and the changes leading to the Airline Deregulation Act is presented. A number of studies are cited that conclude that airline perfor- mance has improved since the Civil Aeronautics Board days. The author agrees with these conclusions but goes on to suggest that it is time to begin comparing the airline industry today with the standards of performance associated with perfect competition instead of the previous regulatory period. A standard of competitive performance is suggested. The traditional p=mc=ac performance is complicated because mc and ac decline for any airline flight until the plane is full or has a 100% load factor. The author suggests p=acat load factors are not yet reaching loo%, it is suggested that some policy modifications might help improve performance further. An- titrust is examined and some other institutional policy changes are sug- gested. 相似文献
143.
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
144.
J B Kempton A Sirignano D H DeGaetano P J Yates W F Rowe 《Journal of forensic sciences》1992,37(6):1534-1540
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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Brandon J. Kinne 《国际研究展望》2005,6(1):114-128
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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