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961.
With increasing frequency, experimental psychologists are called upon to present their research findings and theories in a courtroom. This article reviews the general evidentiary standards regarding such expert testimony, with a specific emphasis on how those principles have been applied in the context of expert psychological testimony on the unreliability of eyewitness identifications. A comprehensive review of the judicial decisions in this area reveals that there has recently been a significant shift in the courts' receptivity toward such testimony. Many courts now believe that psychological research on human perception and memory has progressed to the point that the expert's testimony may be considered both reliable enough and helpful enough to the jury to justify its adminssion in the appropriate case. The author concludes with a discussion of several developments that would help to allay the judicial system's historical concerns over the admission of such expert psychological testimony.  相似文献   
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Fluids from frozen muscle tissue taken from 449 white-tailed deer (Odocoileus virginianus) were analyzed using a radioimmunoassay technique for testosterone. Comparing 309 deer sampled in early November, antlered males had significantly higher tissue testosterone levels (range = 0.18 to 16.00 ng/mL) than females (range = 0.00 to 0.18 ng/mL) while antlerless (fawn) males overlapped both groups (range = 0.00 to 0.68 ng/mL). Samples taken from 132 deer from January through August showed no differences among ages or sexes. Antlered males can be differentiated from females during the breeding season.  相似文献   
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As punishment for lying, the foster mother of a five-year-old white male poured pepper into his throat. He immediately became dyspneic, then apneic, and was pronounced dead about 1 h later. At autopsy, the main stem and several smaller bronchi were occluded with pepper. Mechanisms of asphyxia by pepper include mechanical obstruction of the tracheobronchial tree and mucosal edema caused by the irritant effect of volatile oils in pepper. This rare circumstance represents the second reported fatal case of pepper aspiration and the third reported case overall.  相似文献   
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During the past two decades Nigeria has invested heavily in scientific research, by developing country standards. Yet these investments at best have had only marginal impacts on the activities of the production and service sectors even though there are many priority development activities which could benefit from inputs from Nigerian researchers. At the national level efforts to direct or even co-ordinate the planning and budgeting of research have been seriously hampered by frequent changes in organizational responsibilities and by repeated budget cuts. Historically, the activities of the federal research institutes have been poorly tuned to the interests and capabilities of the potential users of their research products. Neither these institutes nor the universities with research activities are in a position to develop products or processes which can compete with imported technologies that are saturating the economy. However, the research institutes, and to a lesser extent the universities, should make greater contributions in applying science to improved use of the nation's natural resource endowments, although significant changes in research management at the project level are needed if this objective is to be realized. The Government should provide incentives to the multinational companies operating in Nigeria to develop joint programmes with the research institutes and universities as one mechanism for diffusing the administrative and technical capabilities of the companies. Meanwhile, selected public sector enterprises should be encouraged to expand technological innovation efforts which could be directly applied to their production activities.  相似文献   
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