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991.
992.
In previous investigations hair analysis for ethyl glucuronide (EtG) and fatty acid ethyl esters (FAEE) proved to be suitable for the detection of excessive alcohol consumption. The aim of this study was to compare EtG and FAEE concentrations in hair of alcoholics, social drinkers and teetotallers. Hair samples from 10 alcoholics in withdrawal treatment, 11 fatalities with documented excessive alcohol consumption, four moderate social drinkers who consumed up to 20 g ethanol per day, and three strict teetotallers were analysed. After external degreasing with n-heptane, extraction with a dimethyl sulfoxide/n-heptane mixture and headspace solid-phase microextraction of the extracts, four fatty acid ethyl esters (FAEEs) (ethyl myristate, ethyl palmitate, ethyl oleate and ethyl stearate) were analysed by gas chromatography-mass spectrometry (GC-MS) with deuterated internal standards. EtG was determined by GC-MS/NCI after ultrasonication of the samples with H2O, cleanup by SPE with aminopropyl columns and PFP derivatisation. The following concentrations were measured for the four groups: teetotallers EtG < 0.002 ng/mg, FAEE 0.05-0.37 ng/mg, moderate social drinkers EtG < 0.002 ng/mg, FAEE 0.26-0.50 ng/mg, alcoholic patients EtG 0.030-0.415 ng/mg, FAEE 0.65-20.50 ng/mg and the fatalities with alcohol history EtG 0.072-3.380 ng/mg, FAEE 1.30-30.60 ng/mg. The results confirm that by using a cut-off value of the sum of FAEE > 1 ng/mg and/or a positive EtG result in hair, excessive alcohol consumption can be identified using hair analysis. However, no significant correlation between the EtG and FAEE concentrations in the positive cases could be shown. Segmental analysis of some of the specimens did not reveal the same distribution for EtG compared to FAEE in hair, and no chronological accordance compared to the self-reported alcohol consumption could be observed for both parameters. These different results of both methods are discussed in terms of differences between EtG and FAEE in mechanism of formation and incorporation into hair and elimination from hair.  相似文献   
993.
A simple means of detecting the abuse of steroids that also occur naturally is a problem facing doping control laboratories. Specific markers are required to allow the detection of the administration of these steroids. These markers are commonly measured using a set of data obtained from the screening of samples by gas chromatography-mass spectrometry (GC-MS). Doping control laboratories further need to confirm identified abuse using techniques such as gas chromatography-combustion-isotope ratio mass spectrometry (GC-C-IRMS). An interesting urinary species was found while following the pharmacokinetics and changes to the steroid profile from single and multiple oral doses of the International Olympic Committee/World Anti Doping Agency (IOC/WADA) prohibited substance, dehydroepiandrosterone (DHEA). The urine samples collected from the administration studies were subject to GC-MS and GC-C-IRMS steroid analysis following cleanup by solid phase extraction techniques. A useful urinary product of DHEA administration was detected in the urine samples from each of the administration studies and was identified by GC-MS experiments to be 3alpha,5-cyclo-5alpha-androstan-6beta-ol-17-one (3alpha,5-cyclo). This compound occurs naturally but the concentrations of 3alpha,5-cyclo were elevated following both the single DHEA administration (up to 385 ng/mL) and multiple DHEA administrations (up to 1240 ng/mL), in relation to those observed prior to these administrations (70 and 80 ng/mL, respectively). A reference distribution of urine samples collected from elite athletes (n = 632) enabled the natural concentration range of 3alpha,5-cyclo to be established (0-280 ng/mL), with a mean concentration of 22 ng/mL. Based on this an upper 3alpha,5-cyclo concentration limit of 140 ng/mL is proposed as a GC-MS screening marker of DHEA abuse in athletes. GC-C-IRMS analysis revealed significant 13C depletion of 3alpha,5-cyclo following DHEA administration. In the single administration study, the delta13C value of 3alpha,5-cyclo changed from -24.3 per thousand to a minimum value of -31.1 per thousand at 9 h post-administration, before returning to its original value after 48 h. The multiple administration study had a minimum delta13C 3alpha,5-cyclo of -33.9 per thousand during the administration phase in contrast to the initial value of -24.2 per thousand. Preliminary studies have shown 3alpha,5-cyclo to most likely be produced from DHEA sulfate found at high levels in urine. The complementary use of GC-MS and GC-C-IRMS to identify new markers of steroid abuse and the application of screening criteria incorporating such markers could also be adapted by doping control laboratories to detect metabolites of androstenedione, testosterone and dihydrotestosterone abuse.  相似文献   
994.
Two simulated scenes of crime have been studied. Soil traces adhering to boots, sport shoes and tissues have been compared with control samples using particle size analysis. Comparisons of percentage of particles per class interval and multivariate analyses were used to determine how the size distribution of each suspect sample varied compared to the original distribution. A loss of coarse fractions characterized most of the suspect samples even though they were derived from soils having different distributional patterns. However, the differences between control and suspect samples were found to be more important for soils dominated by extreme size classes than for soils rich in medium size particles. The differences among soil samples from the same source were found to be restricted to the extreme size classes. The finding of significant differences within size classes ranging from 1 to 0.063 mm should be then considered as a dissimilarity sign between trace sample and hypothetic control soil.  相似文献   
995.
Decompositional odor analysis database   总被引:1,自引:0,他引:1  
This study, conducted at the University of Tennessee's Anthropological Research Facility (ARF), describes the establishment of the Decompositional Odor Analysis (DOA) Database for the purpose of developing a man-portable, chemical sensor capable of detecting clandestine burial sites of human remains, thereby mimicking canine olfaction. This "living" database currently spans the first year and a half of burial, providing identification, chemical trends and semi-quantitation of chemicals liberated below, above and at the surface of graves 1.5 to 3.5 ft deep (0.45 to 1.0 m) for four individuals. Triple sorbent traps (TSTs) were used to collect air samples in the field and revealed eight major classes of chemicals containing 424 specific volatile compounds associated with burial decomposition. This research is the first step toward identification of an "odor signature" unique to human decomposition with projected ramifications on cadaver dog training procedures and in the development of field portable analytical instruments which can be used to locate human remains buried in shallow graves.  相似文献   
996.
The stable isotope ratios of a seized pathogen culture could potentially reveal information about the environment in which the agent was produced. In this paper we describe general relationships between stable isotopes of carbon, nitrogen, and hydrogen in bacteriological culture media and spores of Bacillus subtilis, an endospore-forming soil bacterium. In numerous media that varied both in nutrient composition and water stable isotope ratios, medium to spore enrichment in carbon isotopes was 0.3 +/- 2.0% per thousand (parts per thousand), and in nitrogen, 4.5 +/- 0.7% per thousand. We achieved mass balance for the contribution of hydrogen isotopes from nutrients (70%) and water (30%) to spores in independent experiments by varying the isotope ratios of nutrients or water. A model was derived for predicting the isotope ratio values of spores from those in nutrients and water.  相似文献   
997.
Within the past decade, restorative justice has emerged as a truly global phenomenon. Although retributive justice has dominated the penal landscape, more recently, restorative principles at sentencing have attracted increased attention. Restorative sentencing emphasizes the importance of compensation and reconciliation between victims and offenders and pays less attention to establishing proportionality between the seriousness of the offense and the severity of the sentence imposed. Although voluminous (and proliferating), the scholarly literature on restorative justice has to date neglected one critical issue: public opinion with respect to this justice paradigm. Public opinion researchers too, have generally overlooked this topic. The goal of this paper is to determine which elements of the new paradigm generate public approval, and which features are likely to encounter or provoke public opposition, drawing upon related international research published in English over the past 20 years (1982–2002). The review reveals widespread support for restorative sentencing options, such as community service, compensation, and restitution, particularly when applied to young offenders. However, it also seems clear that public support for these alternatives to punitive sentencing options declines as the seriousness of the offence increases, suggesting strong public adherence to the retributive principle of proportionality in sentencing.  相似文献   
998.
Literature assessing knowledge of and attitudes toward social issues has demonstrated that mental health professionals and lay persons often differ greatly. To add to the normative information in the field of psychological abuse and to determine whether the differences previously found between mental health professionals and lay persons extend to this field, a sample from each group rated psychologically aggressive items by a husband toward his wife. For the 102 items, psychologists were more likely to label the behaviors as "psychological abuse," but this tendency was due to psychologists considering the behaviors as either "always" or "possibly" abusive, whereas lay persons demonstrated a bimodal response pattern of rating the behaviors as "always" or "never" psychological abuse. Lay persons were much more likely than psychologists to rate items high in terms of severity level, however. The two groups used different contextual factors for determining that a behavior was psychological abuse when they initially were uncertain that it was abusive.  相似文献   
999.
A new AIDS-in-the-Workplace program being implemented in Québec emphasizes the rights of workers living with HIV/AIDS. The program tackles issues such as confidentiality of HIV status, access to insurance benefits, discrimination, and the need for employers to take reasonable measures to accommodate the disabilities of workers.  相似文献   
1000.
Abstract.  Perhaps the strongest empirical finding in political science is 'Gamson's Law': the near-perfect relationship that exists in parliamentary systems between a coalition party's seat contribution to the government and its quantitative allocation of cabinet portfolios. Nevertheless, doubts remain. What would happen if the salience or importance of the various portfolios was also taken into account? Should it not be the case that payoffs correspond with bargaining power rather than seat contributions? And perhaps most significantly, would addressing these issues produce evidence that the parties designated to form governments extract disproportionately large payoffs for themselves, as predicted by 'proposer' models of bargaining? Utilizing the results of a new expert survey of portfolio salience in 14 Western European countries, the authors of this article explore each of these questions. Their basic finding is that salience-weighted portfolios payoffs overwhelmingly mirror seat contributions, contra proposer models and any other models based on bargaining power. The article concludes with a discussion of the implications for formal models of bargaining.  相似文献   
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