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N C Martin A A Pirie L V Ford C L Callaghan K McTurk D Lucy D G Scrimger 《Science & justice》2006,46(3):179-184
In the forensic science laboratory, the recovery of spermatozoa from vaginal swabs, or vaginal cells from penile swabs, can help determine if sexual intercourse may have taken place. There are several methods used to recover spermatozoa and cells from the swabs before visualisation on a microscope slide and most of these methods use water. Phosphate buffered saline (PBS) is a non-toxic solution used in many biological laboratories. Unlike water, PBS prevents cells rupturing or shrivelling up due to osmosis. This study demonstrates that PBS can be used for the extraction of spermatozoa and cells from swabs and that PBS does not affect subsequent DNA profiling. 相似文献
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DAVID WEISBURD LAURA A. WYCKOFF JUSTIN READY JOHN E. ECK JOSHUA C. HINKLE FRANK GAJEWSKI 《犯罪学》2006,44(3):549-592
Recent studies point to the potential theoretical and practical benefits of focusing police resources on crime hot spots. However, many scholars have noted that such approaches risk displacing crime or disorder to other places where programs are not in place. Although much attention has been paid to the idea of displacement, methodological problems associated with measuring it have often been overlooked. We try to fill these gaps in measurement and understanding of displacement and the related phenomenon of diffusion of crime control benefits. Our main focus is on immediate spatial displacement or diffusion of crime to areas near the targeted sites of an intervention. Do focused crime prevention efforts at places simply result in a movement of offenders to areas nearby targeted sites—“do they simply move crime around the corner”? Or, conversely, will a crime prevention effort focusing on specific places lead to improvement in areas nearby—what has come to be termed a diffusion of crime control benefits? Our data are drawn from a controlled study of displacement and diffusion in Jersey City, New Jersey. Two sites with substantial street‐level crime and disorder were targeted and carefully monitored during an experimental period. Two neighboring areas were selected as “catchment areas” from which to assess immediate spatial displacement or diffusion. Intensive police interventions were applied to each target site but not to the catchment areas. More than 6,000 20‐minute social observations were conducted in the target and catchment areas. They were supplemented by interviews and ethnographic field observations. Our findings indicate that, at least for crime markets involving drugs and prostitution, crime does not simply move around the corner. Indeed, this study supports the position that the most likely outcome of such focused crime prevention efforts is a diffusion of crime control benefits to nearby areas. 相似文献
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Toxicologic findings in the USS Iowa disaster. 总被引:5,自引:0,他引:5
The toxicologic results from the 47 victims of the explosion on the USS Iowa are presented. Good correlation between carboxyhemoglobin saturations and cause of death was found. There were no correlations between blood cyanide concentrations and causes of death. Volatile analysis suggested postmortem ethanol production rather than antemortem ethanol ingestion. No drugs except nicotine were detected in any of the victims. 相似文献
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A mock jury study was conducted to test the hypothesis that perceptions of a witness can be biased by presumptuous cross-examination questions. A total of 105 subjects read a rape trial in which the cross-examiner asked a question that implied something negative about the reputation of either the victim or an expert. Within each condition, the question was met with either a denial, an admission, or an objection from the witness's attorney. Results indicated that although ratings of the victim's credibility were not affected by the presumptuous question, the expert's credibility was significantly diminished—even when the question had elicited a denial or a sustained objection. Conceptual and practical implications of these findings are discussed.This research was supported by funds provided to the first author by the Bronfman Science Center. 相似文献
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N D Sperber 《Journal of forensic sciences》1990,35(4):838-844
A review of the available literature does not reveal a plausible explanation as to why the incisal edges of maxillary anterior teeth do not always mark clearly. Generally, the mandibular incisal edges do mark with some consistency. This paper demonstrates through test bites on skin that the answer lies in the position of the mandible. 相似文献