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181.
In forensic evidence, gamma-hydroxybutyric acid (GHB) has frequently been encountered in one of its salt forms (gamma-hydroxybutyrate), but has also been encountered in its free acid form (GHB). Owing to the physical properties, encounters of the free acid have been largely restricted to forensic exhibits comprising aqueous solutions, such as acidic beverages that have been "spiked" or formulated with GHB salts or gamma-butyrolactone (GBL). The analysis of GHB free acid presents particular difficulties including the potential for altering the original proportions of GHB free acid, GHB carboxylate, and GBL in the course of analysis, and discrimination between GHB free acid and carboxylate forms. In this work, the formation of GHB free acid in aqueous solutions (water and/or D2O) was studied as a function of solution pH. Proton nuclear magnetic resonance (1HNMR) and Fourier-transform infrared spectrometry (FT-IR) measurements were obtained on freshly prepared mixtures of NaGHB and HCl stock solutions representing a series of points along the GHB titration curve. Both 1HNMR and FT-IR were shown to track the changing proportions of GHB free acid and carboxylate forms as a function of pH, while simultaneously monitoring for the formation of the lactone (GBL). The results were consistent with acid-base conversion behavior for a carboxylic acid. 1HNMR was shown to provide an ideal means for analysis of aqueous-based GHB/GBL forensic exhibits based on simple dilution of the neat liquid exhibit, without altering the original proportions of GHB free acid, carboxylate, and GBL in the samples.  相似文献   
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The Scent Transfer Unit (STU-100) is a portable vacuum that uses airflow through a sterile gauze pad to capture a volatiles profile over evidentiary items for subsequent canine presentation to assist law enforcement personnel. This device was evaluated to determine its ability to trap and release organic compounds at ambient temperature under controlled laboratory conditions. Gas chromatography-mass spectrometry (GC-MS) analyses using a five-component volatiles mixture in methanol injected directly into a capture pad indicated that compound release could be detected initially and 3 days after the time of collection. Additionally, 15 compounds of a 39-component toxic organic gaseous mixture (10-1000 parts per billion by volume [p.p.b.(v)]) were trapped, released, and detected in the headspace of a volatiles capture pad after being exposed to this mixture using the STU-100 with analysis via GC-MS. Component release efficiencies at ambient temperature varied with the analyte; however, typical values of c. 10% were obtained. Desorption at elevated temperatures of reported human odor/scent chemicals and colognes trapped by the STU-100 pads was measured and indicated that the STU-100 has a significant trapping efficiency at ambient temperature. Multivariate statistical analysis of subsequent mass spectral patterns was also performed.  相似文献   
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Sharp declines in welfare rolls since the passage of welfare reform legislation have led many to label it a social policy success. Using data from prereform and postreform samples of welfare applicants and recipients, as well as ethnographic data on welfare reform implementation, we examine three hypotheses based on concerns raised during the welfare reform debate about the possible effects of new policies on substance abusers and addicts: First, they would be "scared off," or discouraged from applying to aid by welfare's new requirements surrounding work and treatment. Second, they might be "weeded out," or face discrimination in the application process because of concerns about the difficulty of moving them successfully from welfare to work. Third, they might be "bumped down," or shifted to local aid programs rather than moving from welfare to self-sufficiency. Our empirical analysis finds no evidence of scaring off or weeding out, and some evidence of bumping down. Using ethnographic data, we offer some possible explanations for these findings by placing them in the context of policy change and implementation in the years following welfare reform.  相似文献   
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Three geographic areas of Italy have been sampled and genotyped for 9 Y chromosome STRs: DYS19, DYS385, DYS388, DYS389 I and II, DYS390, DYS391, DYS392, DYS393. Sampling was focused on residents of small areas, well distant from major urban centres. Only individuals whose grandfather would live in the same area were included. A total of 210 unrelated individuals were collected. Distribution of genetic variation across the three samples and comparison with previously published Italian database indicated that so far Y chromosome diversity has been only partially explored in the Italian Peninsula.  相似文献   
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A review of the literature was conducted to assess the extent and nature of the practice of requiring parents to transfer custody in order to receive public funding for intensive services needed by their child/adolescent who had a serious emotional disorder. The review focused on the legal and policy basis of this practice as well as its social and psychological impact on child and family. We conclude that the practice of transfer of custody as a requirement for receiving financial aid occurs in a majority of states, though the actual extent of this practice is not known. The major factor influencing the use of transfer of custody appears to be the absence of an appropriate and adequate system of services for children and adolescents with serious emotional disorders. We recommend that the practice of requiring custody transfer for the sole purpose of receiving services be abolished and offer several suggestions for improving acess to services.Preparation of this article was supported in part by the National Institute of Mental Health (NIMH) under contract no. 89MF761903. The authors are grateful to John Burke and Kelly Kelleher of the Division of Biometry and Applied Sciences, NIMH for their assistance on this project. Laurie Flynn, Executive Director for the National Alliance for the Mentally Ill, was very helpful during the informative stage of the project. Barbara Friesen, Director of the Research and Training Center at Portland State University, gave us useful guidance throughout the project. We thank Stephen Hill, Consultant to the National Governors' Association, for his help. We are grateful to Amy Hewitt and Carol Ishler for their assistance in preparing this report. We also would like to acknowledge several individuals who assisted us with research reported in this article. We are grateful to Governor Richard F. Celeste of Ohio for his letter of support for the state survey of custody transfer practices. We appreciate the efforts on behalf of this survey by staff from the State of Ohio, particularly Jean Ellen Stevens, Administrative Assistant to the Director of the Department of Mental Health. Margraret McNally assisted in the compilation of data for both surveys.  相似文献   
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Initial reports of domestic violence are generally made to law enforcement officers who must respond and intervene. A subset of these episodes involves cases in which the victim, and, in many instances her child(ren), have been taken hostage by her husband or partner. Moreover, there are indications that the number of such incidents is growing. The purpose of this project was twofold: (1) to provide one of the first reports on the prevalence and characteristics of these events, and (2) to more closely analyze domestic crisis (hostage) situations using actual case examples. All information was obtained from the Hostage Barricade Database System (HOBAS) of the FBIs Crisis Negotiation Unit. HOBAS is a postincident information collection tool which stores historical data from law enforcement agencies across the nation on hostage/barricade incidents. An examination of this database yielded different types of domestic hostage-taking acts and outcomes (e.g., tactical vs. negotiated resolutions, survival vs. death/injury of perpetrator and/or victim[s]). Implications of the findings, for future crisis negotiation efforts directed toward nonviolent resolution of these high-risk critical incidents, are discussed.  相似文献   
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