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131.
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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The detection of human remains that have been deliberately buried to escape detection is a problem for law enforcement. Sometimes the cadaver dog and handler teams are successful, while other times law enforcement and cadaver dog teams are frustrated in their search. Five field trials tested the ability of four cadaver dog and handler teams to detect buried human remains. Human and animal remains were buried in various forested areas during the summer months near Tuscaloosa, Alabama. The remains ranged in decomposition from fresh to skeletonized. Cadaver dogs detected with varying success: buried human remains at different stages of decomposition, buried human remains at different depths, and buried decomposed human and animal remains. The results from these trials showed that some cadaver dogs were able to locate skeletonized remains buried at a significant depth. Fresh and skeletonized remains were found equally by the cadaver dogs along with some caveats. Dog handlers affected the reliability of the cadaver dog results. Observations and videotape of the cadaver dogs during field trials showed that they were reliable in finding buried human remains. 相似文献
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Between 1781 and 1789 the American states attempted to share the costs of national, public goods through a system of requisitions. This paper uses a simple public goods analysis to show why rational states would not share costs as intended by the Articles of Confederation. This normative argument illustrates a potential flaw in the constitutional design of the Articles and provides insight into the decline of the American Confederation. 相似文献
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Despite the existence of rigid civil service systems in many developing countries providing relative stability of public officials, staff posting and transfers are often based on short‐term political criteria. This means high staff circulation in key government posts, leading to a situation of ‘instability within stability’. This article analyses high staff circulation in the government health services in Balochistan, Pakistan. The analysis is based on literature review, a small pilot study and authors' experience in the province. The article notes that high staff turnover and, more specifically, circulation are context‐specific. Four issues are raised. Firstly, the extent of staff turnover is analysed and references are made to its frequency, the organization and cadre. Secondly, the social and political underpinning of high staff circulation is outlined: political patronage, low implementation of rules, staff preferences and public sector control. Thirdly, the problems of staff turnover are raised with specific reference to the problems of continuity, change and participation. Fourthly, the issue of solutions is raised at two levels: structural change to lessen high staff turnover, and dealing with it on a day‐to‐day managerial level. Lastly, substantive and methodological issues are raised with respect to taking the analysis further. Copyright © 2000 John Wiley & Sons, Ltd. 相似文献
140.
Keith L. Monson Ph.D. Kelsey M. Kyllonen M.A. Jeffrey L. Leggitt M.S. Kelli E. Edmiston M.S. Calvin R. Justus Ph.D. Mark F. Kavlick Ph.D. Maria Phillip B.S.Ch.E. Maria A. Roberts M.S. Candie W. Shegogue M.S. Gabriel D. Watts B.A. 《Journal of forensic sciences》2020,65(6):1894-1907
In addition to having blast mitigation properties, aqueous foam concentrate AFC-380 blast suppression foam is designed to capture aerosolized chemical, biological, and radioactive particles during render-safe procedures of explosive devices. Exposure to aqueous environments and surfactants may negatively affect forensic evidence found at the scene, but the effects of AFC-380 foam and aqueous gel on the preservation and subsequent analysis of forensic evidence have not previously been investigated. Sebaceous finger and palm prints and DNA samples on paper, cardboard, tape, and various metal and plastic items, along with hairs, carpet and yarn fibers, and inks and documents, were exposed to AFC-380 foam. Similar mock evidence was also exposed to a superabsorbent gel of the type found in aqueous gel blocks used for shrapnel containment. Exposure to foam or aqueous gel was associated with a dilution effect for recovered DNA samples, but quality of the samples was not substantially affected. In contrast, exposure to AFC-380 foam or gel was detrimental to development of latent finger and palm prints on any substrate. Neither the hair nor the fiber samples were affected by exposure to either the foam or gel. Indented writing on the document samples was detrimentally affected by foam or gel exposure, but not inks and toners. The results from this study indicate that most types of forensic evidence recovered after being exposed to aqueous gel or blast suppression foam can be reliably analyzed, but latent finger and palm prints may be adversely affected. 相似文献