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221.
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
222.
R. CHRISTOPHER SPICER CIH CHMM HARRY J. GANGLOFF PH.D. Neil Feldscher CIH CSP 《环境索赔杂志》2005,17(1):13-28
Bioaerosol data is often used in cases of building mold infestation alleging damage or adverse health effects upon occupants, despite the lack of consistent sampling and analytical protocols and numerical health-based standards. The most fundamental problem in these scenarios is defining a “significant” difference between a suspect indoor environment and the reference environment, regardless of the type of sampling and analysis utilized. Data interpretation focused upon differences in absolute numerical concentrations of fungi is subject to wide differences in expert opinion. On the other hand, an objective quantification of differences can be expressed in terms of probability and better meets criteria established in evidentiary rules. 相似文献
223.
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
224.
225.
Edward J. Keall 《British Journal of Middle Eastern Studies》2005,32(2):249-292
226.
227.
K Lalu P J Karhunen P Rautiainen 《The American journal of forensic medicine and pathology》1992,13(3):196-198
A 6-month-old girl died suddenly without any previous symptoms of heart failure. Autopsy examination showed cardiomegaly (97 g) with a severely fibrotized myocardium. The left coronary artery was originating from the pulmonary artery. Histologically, the myocardium showed myocardial infarcts of different ages, as well as grossly thickened arterial branches due to increased flow in left-right shunt. We suggest that rare anomalies of the coronary arteries should be considered in the autopsies of suspected sudden infant death syndrome cases. 相似文献
228.
The impact of high temperatures (24 to 39 degrees C) and low to moderately high humidities (20 to 70%) on the applicability of TLC systems for drug identification was studied during a 6 month climatologic cycle in Burkina Faso (West Africa). In general, the Rf values as observed on the plates were found to be substantially affected as compared with values obtained at temperate climates. Some TLC systems were more affected than others and the largest deviations of up to 30 Rf units were at low humidities. Tropical conditions also had a negative effect on the reproducibility of Rf values. However, when an Rf-correction procedure was applied, using reference mixtures of known drugs on each plate, accuracy as well as reproducibility of the resulting Rfc values were drastically improved and data thus corrected were found to be compatible with existing TLC data bases developed under moderate climatological conditions. The impact of high to extremely high humidities (70 to 100%) remains to be investigated. 相似文献
229.
Washington University v. Catalona revolves around ownership of tissue samples provided by patients for research purposes, raising significant ethical and legal questions concerning patient rights, current human research practices, and the treatment of samples as capital resources by the research institution. 相似文献
230.
In this study, a new method was developed for the impurity profiling of illicit MDMA tablets. The extraction efficiency, linearity, repeatability and reproducibility of the method were evaluated. Eighty two MDMA tablets coming from presumed unrelated large seizures in 2004 (n >500 tablets) were analyzed by gas chromatography mass spectrometry (GC-MS) in order to assess the discrimination power of the method. The latter was found to be practical, robust, relatively easy to perform, highly discriminative and yielding good chromatography. In addition, some new impurities were detected and identified. Their chemical structures and mass spectra are reported. 相似文献