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Narcotics "body packing" can be detected in abdominal X-rays by the ring shadow caused by air trapped in the packs. In a series of 82 cases admitted for abdominal X-ray in Helsinki, Finland, in 1982 through 1988, we encountered 9 (11.0%) true positives, 3 (3.6%) false positives, and 1 (1.2%) false negative. The false positives were due to the constipation often associated with the narcotics abuse. The false negative X-ray diagnosis was attributable to an inexperienced radiologist. False negatives may also be associated with packets containing marijuana, packs with few wrappings, aluminum-foil coated packs, and machine-packed narcotics. Searching for trapped air in radiographs, repeated X-raying by an experienced radiologist, use of computed tomography, or combined urinary drug screening may be applied to diminish false findings and to avoid unnecessary arrest for the purpose of fecal screening over several days. 相似文献
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The post-mortem cooling of the human head, over the first fifteen hours after death, was measured by infrared thermology. A detailed temperature map of the head and face was obtained by the use of image processing techniques and the cooling behaviour of twelve preselected facial features was observed. The two main findings of the study were a difference in cooling pattern between the upper and the lower part of the head, and a consistency in the cooling pattern of the lower part of the head in all the cases studied. A comparison of various model fits to the raw data was undertaken and the "best" bodies, models and features were determined on a statistical basis. The formula that best fitted the raw data was a novel double application of Newton's law. The features with the least error in data fitting were the chin and zygoma; that with the most error was the mouth. 相似文献
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The Equal Employment Opportunity Commission (EEOC) recently issued its final regulations on the Americans with Disabilities Act (ADA). Although the regulations offer some guidance for employers on how to comply with the Act, they fail to provide specific answers to the many complicated compliance questions that will surely arise. Further, the regulations are almost totally silent on certain critical issues related to insurance, workers' compensation, and potential conflicts between ADA obligations and terms of collective bargaining agreements. The EEOC has essentially left the resolution of many important ADA questions to case-by-case determination and the litigation process. 相似文献
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Circumventing formal structure through commitment: Presidential influence and agenda control 总被引:1,自引:0,他引:1
Although the formal institutional structure that defines the temporal order of play in a policy game between the Congress and President ought to provide Congress with agenda power, the President is traditionally treated as the dominant player in this relationship. We show that if the President can make clear-cut commitments, presidential commitment can counter the dominance hierarchy and the complexion of equilibrium outcomes. Thus, the details of political interactions (in particular, the possibilities for commitment) may be as important as the formal specification of institutional structure.We thank Peter Aranson, David Austen-Smith, Ed Campos, Gerry Faulhaber, Art Frank, Ken Koford, William Riker, Janet Pack, the anonymous referees, and seminar participants at the University of Delaware, the University of Pennsylvania, and the University of Rochester for helpful comments, subject to the usual caveat. We also thank Joel Friedlander and Harold Dichter for research assistance. 相似文献
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