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81.
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Reviews the need for and development of expanded school mental health (ESMH) programs, which provide a continuum of mental health promotion and intervention through school–community partnerships. Since ESMH is a relatively new, but increasingly prominent field, countless issues are being addressed in practice and research and in efforts to bridge practice and research. We review particular content and context dimensions of ESMH in need of development including quality assessment and improvement, empirically supported practice, improving assessment and outcome evaluation, involving educators in the work, understanding school environments, and tailoring programs through qualitative research. Summaries of articles that amplify these themes are provided.  相似文献   
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A meta-analytic review of research comparing biased and unbiased instructions in eyewitness identification experiments showed an asymmetry; specifically, that biased instructions led to a large and consistent decrease in accuracy in target-absent lineups, but produced inconsistent results for target-present lineups, with an average effect size near zero (Steblay, 1997). The results for target-present lineups are surprising, and are inconsistent with statistical decision theories (i.e., Green & Swets, 1966). A re-examination of the relevant studies and the meta-analysis of those studies shows clear evidence that correct identification rates do increase with biased lineup instructions, and that biased witnesses make correct identifications at a rate considerably above chance. Implications for theory, as well as police procedure and policy, are discussed.  相似文献   
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Degradation of human DNA extracted from forensic stains is, in most cases, the result of a natural process due to the exposure of the stain samples to the environment. Experiences with degraded DNA from casework samples show that every sample may exhibit different properties in this respect, and that it is difficult to systematically assess the performance of routinely used typing systems for the analysis of degraded DNA samples. Using a batch of artificially degraded DNA with an average fragment size of approx. 200 bp a collaborative exercise was carried out among 38 forensic laboratories from 17 European countries. The results were assessed according to correct allele detection, peak height and balance as well as the occurrence of artefacts. A number of common problems were identified based on these results such as strong peak imbalance in heterozygous genotypes for the larger short tandem repeat (STR) fragments after increased PCR cycle numbers, artefact signals and allelic drop-out. Based on the observations, strategies are discussed to overcome these problems. The strategies include careful balancing of the amount of template DNA and the PCR cycle numbers, the reaction volume and the amount of Taq polymerase. Furthermore, a careful evaluation of the results of the fragment analysis and of automated allele calling is necessary to identify the correct alleles and avoid artefacts.  相似文献   
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Each year over 3 million new chainsaws are sold in the United States. The operation of these newer saws combined with the millions of older chainsaws in circulation results in over 28,000 chainsaw-related injures annually. The majority of the injuries involve the hands and lower extremities with less than 10% involving injuries to the head and neck regions. Deaths while operating a chainsaw are extremely rare. The most common hazards associated with chainsaws are injuries caused by kickback, pushback, and pull-in. Kickback is the most common and poses the greatest hazard. Kickback occurs when the rotating chain is stopped suddenly by contact with a more solid area throwing the saw rapidly backward toward the operator. The cause of most injuries can be traced to improper use of the saw or poor judgment on part of the operator. We present two fatal chainsaw deaths; one with an older style saw, and the other with a modern type. In both cases the victims died from fatal injuries received to the neck region from a chainsaw kickback. The first case involved a 49-year-old white male operating an older style chainsaw with limited safety features. The second case involved a 38-year old white male who was operating a newer model chainsaw equipped with a low kickback chain in an unsafe manner.  相似文献   
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A cardiac concussion is caused by a sudden, nonpenetrating, localized impact to the chest that is theorized to result in almost simultaneous sudden death from a disruption to the conductive system. The detailed external/internal forensic examination of the body reveals no evidence of structural, pathologic, or histologic signs of trauma to the heart. A cardiac concussion is a rare and often overlooked cause of sudden death. This type of sudden death is typically seen among younger individuals participating in sports involving projectiles and, to a lesser degree, where collisions occur. Cardiac concussions are clinically, pathologically, and chemically different from a cardiac contusion. The objective of this paper will be to define cardiac concussion, differentiate between cardiac concussion and cardiac contusion, and describe the clinical and pathologic features of a 32-year-old white male who died of a cardiac concussion following a collision with a catcher during a softball game. The civil ramification of incorrectly diagnosing the manner of death in cases of death involving a cardiac concussion will also be addressed.  相似文献   
90.
Pinker S 《Time》2003,161(3):98-100
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