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71.
A number of recent studies have explored the consequences ofinterracial peer effects on the academic and social performanceof minority students. This article contributes to that discussion,focusing, however, on perceptions rather than behaviors. Theanalysis suggests that exposure to white peers is associatedwith declining perceptions of racial justice among black andLatino high school students. While cautioning against causalinterpretations of this finding, the article suggests that theintegrationist aims of Brown v. Board of Education will notbe satisfied without more thoughtful and vigorous desegregationefforts.  相似文献   
72.
"Brain death," the determination of human death by showing the irreversible loss of all clinical functions of the brain, has become a worldwide practice. A biophilosophical account of brain death requires four sequential tasks: (1) agreeing on the paradigm of death, a set of preconditions that frame the discussion; (2) determining the definition of death by making explicit the consensual concept of death; (3) determining the criterion of death that proves the definition has been fulfilled by being both necessary and sufficient for death; and (4) determining the tests of death for physicians to employ at the patient's bedside to demonstrate that the criterion of death has been fulfilled. The best definition of death is "the cessation of functioning of the organism as a whole." The whole-brain criterion is the only criterion that is both necessary and sufficient for death. Brain death tests are used only in the unusual case in which a patient's ventilation is being supported. Brain death critics have identified weaknesses in its formulation. But despite its shortcomings, the whole-brain death formulation comprises a concept and public policy that make intuitive and practical sense and that has been well accepted by many societies.  相似文献   
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This paper describes an effort by industry and university partners to centralize manufacturing decision making through the development of generic simulation tools. This ongoing, cooperative process improvement initiative between the Industrial and Systems Engineering faculty at the University of Alabama in Huntsville (UAH) and Chrysler’s Huntsville Electronics Division (HED) permits the involved faculty to broaden their experience and technical expertise in electronics fabrication, while the industry partner benefits from the transfer of technical knowledge and advanced analysis methodologies from the university. The focus of the project is the definition of generic electronic manufacturing models that can be easily defined and implemented through common user-oriented interfaces, allowing users who are not familiar with simulation and simulation languages to address the needs of their particular functional areas.  相似文献   
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Andrew M. Greeley is a priest, sociologist, novelist, and journalist. His scholarly writings concentrate on religion and ethnicity. His other writings range from critiques of the Catholic church to best-selling novels.  相似文献   
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This paper describes a collaborative exercise intended to demonstrate whether uniformity of DNA profile results could be achieved between different European laboratories. It was shown that this goal can be obtained provided that a common protocol is followed (specifically the use of a common electrophoretic buffer as being the most important parameter). Generally, lower molecular weight loci (with lower molecular weight fragments) such as YNH24 perform better than higher molecular weight loci such as MS43a. The results of the exercise are discussed in relation to the objectives of the European DNA profiling group (EDNAP).  相似文献   
79.
The impact of high temperatures (24 to 39 degrees C) and low to moderately high humidities (20 to 70%) on the applicability of TLC systems for drug identification was studied during a 6 month climatologic cycle in Burkina Faso (West Africa). In general, the Rf values as observed on the plates were found to be substantially affected as compared with values obtained at temperate climates. Some TLC systems were more affected than others and the largest deviations of up to 30 Rf units were at low humidities. Tropical conditions also had a negative effect on the reproducibility of Rf values. However, when an Rf-correction procedure was applied, using reference mixtures of known drugs on each plate, accuracy as well as reproducibility of the resulting Rfc values were drastically improved and data thus corrected were found to be compatible with existing TLC data bases developed under moderate climatological conditions. The impact of high to extremely high humidities (70 to 100%) remains to be investigated.  相似文献   
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