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Gimbel B 《Newsweek》2004,143(18):62-63
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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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This study assessed the role of rape myth acceptance (RMA) and situational factors in the perception of three different rape scenarios (date rape, marital rape, and stranger rape). One hundred and eighty-two psychology undergraduates were asked to emit four judgements about each rape situation: victim responsibility, perpetrator responsibility, intensity of trauma, and likelihood to report the crime to the police. It was hypothesized that neither RMA nor situational factors alone can explain how rape is perceived; it is the interaction between these two factors that best account for social reactions to sexual aggression. The results generally supported the authors' hypothesis: Victim blame, estimation of trauma, and the likelihood of reporting the crime to the police were best explained by the interaction between observer characteristics, such as RMA, and situational clues. That is, the less stereotypic the rape situation was, the greater was the influence of attitudes toward rape on attributions.  相似文献   
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Despite widespread institutional and professional support, the recommendations of the Bristol Royal Infirmary Inquiry may be insufficient to reduce patient risk from impaired senior medical practitioners. Using the First Inquiry into Neurosurgical Services at the Canberra Hospital as a case study, this article argues that the Bristol-type recommendations--which emphasise reformulation of clinical governance structures, including early reporting of "sentinel events" and compulsory clinical audits--will be ineffective without a reformed institutional ethos that encourages open transparency and respect for those committed to such processes. Such reformulation may need to commence in medical education and involve new strategies including the use of portable digital technology to facilitate self-assessment of performance and immediate reporting of adverse incidents.  相似文献   
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能源供应的可靠性和战略稳定性要求俄罗斯在能源领域必须实现燃料—能源资源的部门结构和分布多元化。煤炭运输未来发展的预测是根据“2 0 2 0年前俄罗斯的能源战略”制定的 ,该战略确定了燃料由目前占绝对优势的碳氢化合物 (石油和天然气 )向煤炭、核能和再生材料过渡的进程。同时 ,能源战略的一些指标应该考虑到经济和能源中长期发展计划的可行性和实现性。建立国家未来的起支撑作用的运输网的首要任务 ,是修筑北西伯利亚铁路线  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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The second part of the paper on suicides by gunshots to the head in the presence of witnesses focuses on relevant morphological autopsy findings such as entrance site, signs of close range or contact shots, bullet path etc. and also discusses selected aspects of ascertaining gunshot residues. For the identification of the shooter an integral medicolegal assessment of all the facts including the investigation results and the autopsy findings is essential. However, the morphological findings alone do not allow safe diagnosis, as for example in a homicide the temporal region, which was affected in all our cases, may have been deliberately chosen by the perpetrator as a localization typical of suicide. Thus methods to ascertain gunshot residues on the firing hand (by means of adhesive films and the polyvinyl-alcohol collection method--PVAL) are of great practical importance. In seven cases adhesive films and/or the polyvinyl-alcohol collection method were used. In one case the gunshot residues (GSR) were analysed by means of tape lifts and subsequent scanning electron microscopy (SEM). It was found that especially the combined application of topographical (adhesive tape/PVAL) and cumulative (SEM) methods allowed for the doubtless identification of the shooter, thus usually confirming the suicide. By the example of one case it is demonstrated that without the immediate collection of evidence at the scene objective reconstruction of the event becomes impossible. On the basis of the reported cases recommendations are finally given for a differentiated approach in the medicolegal evaluation of alleged witnessed suicide by gunshot (to the head).  相似文献   
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