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131.
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   
132.
"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   
133.
Ethanol was determined by gas chromatography in a variety of tissues and body fluids secured at autopsy in 61 cases. The specimens tested included right and left heart blood, femoral blood, pericardial fluid, cerebrospinal fluid, vitreous humor, urine, stomach contents, and brain. Statistical analysis of the cases revealed no significant differences among the various blood sites tested. However, the variations in blood ethanol concentrations among the various sampling sites within each case were as follows: 40 cases showed differences of less than 25%; 16 cases revealed variability between 25% and 50%, 4 cases had differences exceeding 50%. In one case, satisfactory blood analyses could not be accomplished. The larger variances occurred especially in those instances in which stomach alcohol concentration was 0.50% or greater. In one case, the variability amongst the different blood sites exceeded 400% (femoral blood--0.043%, right atrium--0.070%, root of aorta--0.156%); the brain was 0.050%, and the stomach contents was 1.2%. For all 61 cases, variances in blood alcohol content among the different sampling sites in a single cadaver ranged from 1.8 to 428%.  相似文献   
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Conclusion The Regulations appear to have reinforced the protection available to software producers under United Kingdom law. The provisions of the Software Directive and the Regulations are complex and not without significant inconsistencies which are likely to prove to be a source of litigation. The drafters of the Regulations chose, unlike many of its European partners, not to adopt the wording of the Software Directive but to write their own interpretation, adding an element of uncertainty to the law in this area, which is perhaps inevitable bearing in mind the linguistic problems of translating and interpreting any directive coupled with the ambiguity and omission of definitions of several key terms. More important, however, than any academic argument will be the practical impact of the new law and its effectiveness in achieving its aim.  相似文献   
136.
For helpful suggestions and criticism I am grateful to Delf Buchwald (Göttingen), Malte Dießelhorst (Göttingen), Ralf Dreier (Göttingen), Bonnie Litschewski Paulson (Göttingen and St. Louis), Martin Schulte (Münster), Alexander Somek (Vienna), and Kenneth I. Winston (Boston). In correspondence, Walter Ott (Zurich) and Carola Vulpius (Dresden) responded in a most helpful way to my queries.  相似文献   
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This paper examines nine cases of “spinback,” the flow back to laboratories of technical advantage from technology transfer activities. The benefits revealed in the cases are discussed and assessed for their value to the participating laboratories and the scientists involved. The objective of this study was to explore and test the feasibility of undertaking a comprehensive study of the value of spinback in order to encourage support for technology transfer activities by middle management in a laboratory. Spinback is defined as the phenomenon by which scientists’ and engineers’ participation in technology utilization activities results in a technically valuable flow back to their laboratories or organizations, thereby increasing or improving techical capability. It was anticipated that this exploration would provide evidence that the phenomenon does occur, with important consequences for the organization.  相似文献   
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140.
Deoxyribonucleic acid (DNA) typing of ribosomal ribonucleic acid (rRNA) genes was performed with a polymerase chain reaction (PCR) assay for species identification. A variable region of the 28S ribosomal RNA gene was amplified with primers complementary to flanking sequences phylogenetically well conserved. The products of twelve animal DNAs (human, Japanese monkey, dog, cattle, pig, cat, rabbit, mouse, rat, chicken, frog, and fish) were separated by polyacrylamide gel electrophoresis, each revealing a few bands ranging from 150 to 100 base pairs. The band patterns obtained from each DNA sample differed in number and size, which indicates the applicability of the method to species identification. Samples containing either as little as 1 pg of DNA or degraded DNA of 0.2 to 0.5 kb in length were able to give detectable bands. Postmortem human tissue DNAs were tested as an example. They showed a pattern identical to the human control one, which was distinct from those of the other animals examined.  相似文献   
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