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71.
The in vitro production of GHB was observed in freshly collected, untreated whole blood samples using glass BD-Vacutainers and polypropylene S-monovettes. GHB concentrations were determined daily over a period of one week and after 3, 6 and 9 weeks again. Furthermore, the GHB concentration in 40 untreated random whole blood samples stored at 4°C for a longer period of time (10 samples 12 month, 10 samples 24 month and 20 samples 36 month) was also determined. For comparison, the in vitro production of GHB in freshly collected and prepared serum samples was observed. GHB serum concentrations were determined three times over a period of one week and once again after six weeks. Sample preparation was performed by means of methanolic extraction following the precipitation of whole blood and serum samples. A methanolic standard calibration was done in a low range of 0.005-0.1 μg/mL (LOD: 0.004, LLOQ: 0.013). For quantification a spiked blood bank serum with a determined GHB concentration of 0.09 μg/mL was used. Corrected calibrations in the range of 0.09-5.09 μg/mL were used (LOD: 0.08 μg/mL, LLOQ: 0.30 μg/mL), recovery: 91.3% (high level: 4.09 μg/mL) 50.5% (low level: 0.19 μg/mL). RESULTS: Relevant elevation of GHB was observed in all whole blood samples stored in liquid form (4°C or room temperature). In two of the 40 whole blood samples stored over a longer period of time at 4°C, GHB concentrations in the range of 13 μg/mL were even determined. These findings constitute grounds for caution. Even a GHB cut-off level of 5 μg/mL cannot be considered as "absolutely positive" proof of a case of exogenous administration, at least in untreated liquid blood samples in long time storage. However, no significant elevations of GHB were otherwise observed in any of the serum samples independently of storage temperature nor in the whole blood samples that were frozen for storage. CONCLUSIONS: The results suggest that the cut-off for exogenous GHB of 5 μg/mL could be lowered significantly, with the consequence of winning valuable time for the potential victim, but only if serum is collected for GHB determination or if the whole blood sample is frozen immediately after collection and the procedure well documented.  相似文献   
72.
Sequencing mitochondrial DNA hypervariable regions I and II (HVI and HVII) is useful in forensic missing person and unidentified remains cases. Improvements in ease and sensitivity of testing will yield results from more samples in a timely fashion. Routinely, amplification of HVI and HVII is followed by Sanger sequencing using the BigDye® Terminator v3.1 Cycle Sequencing kit (Applied Biosystems) using 4 μL of ready reaction mix (RRM). Each sequencing reaction is then purified through column filtration before capillary electrophoresis. Using lower amounts of RRM (2 μL or 1 μL) and purification using BigDye® XTerminator? (Applied Biosystems) instead of columns showed no loss of sequence length and increased the quality and the sensitivity of testing, allowing HVI and HVII typing from mitochondrial genome equivalent to 125 fg of nuclear DNA, or 100 pg of HVI/HVII amplicons. Using this methodology, testing can be completed in 1 day, and the cost of testing is reduced.  相似文献   
73.
Gas chromatography–mass spectrometry (GC–MS) data of ignitable liquids in the Ignitable Liquids Reference Collection (ILRC) database were processed to obtain 445 total ion spectra (TIS), that is, average mass spectra across the chromatographic profile. Hierarchical cluster analysis, an unsupervised learning technique, was applied to find features useful for classification of ignitable liquids. A combination of the correlation distance and average linkage was utilized for grouping ignitable liquids with similar chemical composition. This study evaluated whether hierarchical cluster analysis of the TIS would cluster together ignitable liquids of the same ASTM class assignment, as designated in the ILRC database. The ignitable liquids clustered based on their chemical composition, and the ignitable liquids within each cluster were predominantly from one ASTM E1618‐11 class. These results reinforce use of the TIS as a tool to aid in forensic fire debris analysis.  相似文献   
74.
Renewed interest in communities as spaces for criminal opportunity has generated numerous studies of neighborhood social dynamics and crime. Most of this research is rooted in social disorganization theory, which examines neighborhood structural characteristics that facilitate effective social control. While many studies tout the benefits of community-based controls, the potential externalities of these efforts remain underexplored. In the modern neoliberal context, where policing strategies stress community involvement and often focus on vaguely-defined problems like “quality of life” or “incivilities” and where police have considerable enforcement discretion, the unintended consequences of community-based controls are important to document. I use the ethnographic case study of Gardner Village to explore the potential collateral consequences of one form of collective social control: new parochialism. Applying a critical lens to the social disorganization literature, I argue that when embedded in particular structural contexts, new parochialism contributes to the reproduction of inequality and undermines community-building processes.  相似文献   
75.
This study examined the nature and extent of probable posttraumatic stress disorder (PTSD) among men in a substance abuse treatment program in a large urban jail. Specifically, it explored the prevalence of probable PTSD and other psychiatric problems among jail detainees, the types of trauma detainees experienced during different phases of their lives, and how those experiences might have contributed to the development of probable PTSD. Results showed that psychiatric problems were quite serious; nearly one-quarter of the sample reported previous psychiatric hospitalization, and nearly 10% were being currently treated with psychiatric medication. In addition, 21% of the sample met the criteria for probable PTSD, a rate five times greater than that in the general population. The current study suggests that the presence of probable PTSD among male detainees should be incorporated into the creation and implementation of jail-based behavioral healthcare services, including screening, assessment, and clinical interventions. Furthermore, in-custody drug treatment programs should adopt trauma-informed strategies for all program participants as the expected standard of care.  相似文献   
76.
With the large and growing number of persons with mental illnesses under probation supervision, a form of specialized probation called specialized mental health caseload (SMHC) has been implemented. This study explores the effectiveness of a prototypic SMHC implemented statewide. A quasi-experimental design was used to compare criminal justice, mental health, and community engagement outcomes among three caseloads: a newly established SMHC supervising no more than 30 clients per officer (N = 1367); an established SMHC supervising roughly 50 clients per officer (N = 495); and a traditional caseload of clients receiving mental health treatment and supervised by officers with average caseloads of over 130 clients (N = 5453). Using a mixed methods approach, we found that the SMHC was implemented with high adherence to fidelity, and comparisons based on different caseload samples generally support the effectiveness of the specialized mental health caseload, particularly on criminal justice outcomes. Future studies using random assignment are needed to examine the connection among mental health symptoms, compliance with treatment and probation supervision, and recidivism.  相似文献   
77.
78.
Forensic fractographic features of bone reliably establish crack propagation in perimortem injuries. We investigated if similar fracture surface features characterize postmortem fractures. Experimentally induced peri- and postmortem fractures were used to assess if fractographic features vary as bone elasticity decreases during the postmortem interval (PMI). Thirty-seven unembalmed, defleshed human femoral shafts from males and females aged 33–81 years were fractured at varying PMIs with a drop test frame using a three-point bending setup and recorded with a high-speed camera. Vital statistics, cause of death, PMI length, temperature, humidity, collagen percentage, water loss, fracture energy, and fractography scores were recorded for each sample. Results showed that fractographic features associated with perimortem fractures were expressed in PMIs up to 40,600 accumulated degree hours (ADH), or 60 warm weather days. Hackle was the most consistently expressed feature, occurring in all fractures regardless of ADH. The most variable characteristics were wake features (78.4%) and arrest ridges (70.3%). Collagen percentage did not correlate strongly with ADH (r = −0.04, p = 0.81); however, there was a strong significant correlation between ADH and water loss (r = 0.74, p < 0.001). Multinomial logistic regression showed no association between fractographic feature expression and ADH or collagen percentage. In conclusion, forensic fractographic features reliably determine initiation and directionality of crack propagation in experimentally induced PMIs up to 40,600 ADH, demonstrating the utility of this method into the recent postmortem interval. This expression of reliable fractographic features throughout the early PMI intimates these characteristics may not be useful standalone features for discerning peri- versus postmortem fractures.  相似文献   
79.
ABSTRACT

The emphasis on local or hybrid efforts in peacebuilding literature brings front and centre the importance of being rooted within a particular context, with leadership and vision for social change and justice proffered by local actors. This is the same emphasis found in development literature and a necessary foundation for transformation. Scholars and practitioners nevertheless also note a role for outsiders in supporting local efforts (eg Lederach in 2005). Yet a significant challenge arises for outsiders, and to some extent local actors: how do you know what was tried or is underway that you might support or from which you might learn? This paper reports findings from a collaborative research project that examined the gap between the practice of peacebuilding locally and internationally available ‘knowledge’ via publications produced on local peacebuilding in Jos, Nigeria, between 2001 and 2008. It identifies a staggering gap between efforts and knowledge in the form of publications. The paper discusses the implications of the findings in terms of what it means for outsiders when thinking about helping resource local transformation efforts.  相似文献   
80.
Recent increases in deaths in the United States from synthetic opioids such as fentanyl and fentanyl analogues (fentanyls) have raised concerns about possible occupational exposures to these potent agents. Medicolegal death investigators and autopsy suite staff might perform job tasks involving exposure to fentanyls. The potential for exposure to fentanyls among medicolegal death investigators and autopsy technicians at a state medical examiner's office was evaluated through review of caseload characteristics, injury and illness logs, and procedures and policies and discussions with management and employee representatives. The evaluation showed that this medical examiner's office had low potential for work-related exposure to fentanyls; its standard operating procedures and personal protective equipment requirements should reduce the potential for occupational exposure. Medicolegal death investigation agencies can develop and implement guidance to control exposures and provide workforce education and training to reduce the potential for work-related exposure to fentanyls.  相似文献   
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