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Presley L Lehrer M Seiter W Hahn D Rowland B Smith M Kardos KW Fritch D Salamone S Niedbala RS Cone EJ 《Forensic science international》2003,133(1-2):22-25
Identification of 6-acetylmorphine, a specific metabolite of heroin, is considered to be definitive evidence of heroin use. Although 6-acetylmorphine has been identified in oral fluid following controlled heroin administration, no prevalence data is available for oral fluid specimens collected in the workplace. We evaluated the prevalence of positive test results for 6-acetylmorphine in 77,218 oral fluid specimens collected over a 10-month period (January-October 2001) from private workplace testing programs. Specimens were analyzed by Intercept immunoassay (cutoff concentration=30 ng/ml) and confirmed by GC-MS-MS (cutoff concentrations=30 ng/ml for morphine and codeine, and 3 ng/ml for 6-acetylmorphine). Only morphine-positive oral fluid specimens were tested by GC-MS-MS for 6-acetylmorphine. A total of 48 confirmed positive morphine results were identified. An additional 107 specimens were confirmed for codeine only. Of the 48 morphine-positive specimens, 32 (66.7%) specimens were positive for 6-acetylmorphine. Mean concentrations (+/-S.E.M.) of morphine, 6-acetylmorphine and codeine in the 32 specimens were 755+/-201, 416+/-168 and 196+/-36 ng/ml, respectively. Concentrations of 6-acetylmorphine in oral fluid ranged from 3 to 4095 ng/ml. The mean ratio (+/-S.E.M.) of 6-acetylmorphine/morphine was 0.33+/-0.06. It is suggested that, based on controlled dose studies of heroin administration, ratios >1 of 6-acetylmorphine/morphine in oral fluid are consistent with heroin use within the last hour before specimen collection. The confirmation of 6-acetylmorphine in 66.7% of morphine-positive oral fluid specimens indicates that oral fluid testing for opioids may offer advantages over urine in workplace drug testing programs and in testing drugged drivers for recent heroin use. 相似文献
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Statistics describe realities, but they also shape them, since they are used to design or support policies. As such accurate statistics are important. Using the agricultural sector in Rwanda as a case study, we demonstrate that dubious statistics can spread quickly. According to data from the Food and Agricultural Organization (FAO), yields have increased by 60 per cent since the implementation of large scale agricultural reforms, while other datasets point towards more modest gains. Yet, estimates in line with those of the FAO dominate the official discourse. We suggest that the discrepancies between datasets may be explained by the difficulties of collecting accurate agricultural statistics combined with an incentive to overestimate yields to show that the reforms have worked. 相似文献
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The Steering Group as Policy Advice Instrument: A Case of “Consultocracy” in Stadium Subsidy Deliberations 总被引:1,自引:0,他引:1
This study considers the use of steering groups and private consultants as sources of policy advice to local governments. More particularly, our research addresses the combined role of a government-appointed working party and consulting firm in the deliberation process precipitating from proposals to renovate/re-build a sports stadium. Through this New Zealand-based case, we explore the political tensions arising from the Working Party's mandates to consult and its role as vehicle to market policy solutions. Data is gleaned from interviews with working party members (and their consultants), observations of public consultations and analysis of documents (e.g., background papers, reports, and press releases). Implications of this institutional arrangement are discussed in light of recurring logics, tensions and paradoxes. We first consider the Carisbrook Working Party as an instrument of policy advice and distinguish its founding logic from other forms such as task forces or commissions of inquiry. We further discuss the paradoxes of the Working Party's procedural and political imperatives including its roles as facilitators of the process, advocates of the “problem,”and as authoritative proclaimers of certainty. 相似文献
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Quantification of Maxillary Dental Arcade Curvature and the Estimation of Biological Ancestry in Forensic Anthropology 下载免费PDF全文
Melissa A. Clark B.A. B.A. Debbie Guatelli‐Steinberg Ph.D. Mark Hubbe Ph.D. Sam Stout Ph.D. 《Journal of forensic sciences》2016,61(1):141-146
Previous studies suggest that palate shape is a useful indicator of biological ancestry in human remains. This study evaluates interobserver error in ancestry estimation using palate shape and explores palate shape variation in Gullah (descendants of West Africans) and Seminole (Indigenous American) population samples using geometric morphometric analysis. Ten participants were asked to ascribe biological ancestry and shape to 28 dental casts based on a classification scheme employed in previous studies. The mean correct classification was 42.0%, indicating that the likelihood of assigning the correct ancestry is very poor and not significantly different from random assignment (p = 0.12). The accuracy analysis based on categorical classification of the casts was complemented by geometric morphometric analysis of nine 3D landmarks reflecting palate shape of 158 casts. Principal component analysis results show no difference between populations regarding palate shape, and cross‐validated discriminant function analysis correctly classified only 62.0% of the specimens. Combined, these results show that previous methods to estimate ancestry are inaccurate and that this inaccuracy is probably due to a lack of palate shape differences between groups, rather than limitation of the analytical method per se. Therefore, we recommend caution should be used when choosing to apply the analysis of palate shape in forensically relevant contexts. 相似文献
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Sam Mullins 《冲突和恐怖主义研究》2013,36(9):811-830
Although the psychology of terrorism is far from a neglected subject, there is still much to learn. “Ordinary” criminals remain enigmatic but have proved a far more accessible population for research purposes. This article bridges the gap between the study of crime and contemporary terrorism by examining the parallels between the two. Significant similarities are shown to exist between terrorists and organized as well as low-level criminals, including activities performed and systems of social influence and organization. Processes of social identification are universally important to varying degrees; however, specific differences in identity may represent key distinguishing features between groups. Although further comparisons utilizing more restrictive samples are necessary, attention is drawn to the sometimes underutilized potential that criminological research holds to act as a point of reference for the investigation of terrorism. 相似文献
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Engineering problems are one factor limiting low cost access to low earth orbit. Insurance and range costs also hinder low cost access. Achieving low cost orbital access requires dealing with economic limitations of chemical rockets, lack of business planning, and failure to identify a workable path that will take us from an immature to a mature launch industry. A mature launch industry exhibiting low cost to orbit and significant flight rates by reusable vehicles with long lifetimes will not evolve unless this multifactorial problem is solved. 相似文献