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891.
Pregabalin is a Schedule V controlled substance which is defined as the (S) enantiomer of 3‐(aminomethyl)‐5‐methylhexanoic acid. It is used legitimately to treat neuropathy in patients with diabetes as well as for epilepsy and fibromyalgia. Pregabalin is an amino acid and an amphoteric compound, which makes it difficult to analyze using the conventional GC‐MS instrumentation found in most forensic drug analysis laboratories. Problems associated with the traditional GC‐MS analysis of pregabalin include selective solubility, ring closure to the corresponding lactam in the GC injection port and/or the MS transfer line and difficulty with chiral derivatization due to the presence of a carboxylic acid moiety. Here, we show that these challenges can be overcome by methylating (capping) the carboxylic acid portion of the pregabalin molecule and converting to the corresponding methyl ester. Once the methyl ester is synthesized, chiral derivatization at the amine can be achieved to identify the controlled (S) enantiomer of pregabalin via GC‐MS. 相似文献
892.
We test structural hypotheses regarding police-caused homicides of minorities. Past research has tested minority threat and community violence hypotheses. The former maintains that relatively large minority populations are subjectively perceived as threats and experience a higher incidence of police-caused homicide than whites do, the latter that higher rates of violent crime among minorities create objective threats that explain these disparities. That research has largely ignored some important issues, including: alternative specifications of the minority threat hypothesis; the place hypothesis, which maintains highly segregated minority populations are perceived as especially threatening by police; and police-caused homicide in the Hispanic population. Using data for large U.S. cities, we conducted total-incidence and group-specific analyses to address these issues. A curvilinear minority threat hypothesis was supported by the Hispanic group-specific findings, whereas the place hypothesis found strong support in both total and group-specific analyses. These results provide new insights into patterns of police-caused homicide. 相似文献
893.
Claire Abernathy Kevin M. Esterling Justin Freebourn Ryan Kennedy William Minozzi Michael A. Neblo Jonathan A. Solis 《Legislative Studies Quarterly》2019,44(4):617-646
Telephone town halls are an increasingly prevalent method for members of Congress (MCs) to communicate with constituents, even while garnering popular criticism for failing to facilitate engagement and accountability. Yet scholars have paid little attention to the events and their effects, and even less to how they might be improved. To remedy this problem, we report on a field experiment in which four MCs joined their constituents in telephone town halls. Overall, participation in an event improved constituents’ evaluations of the format in general, and of the MC in particular. Furthermore, we studied how these events might be improved by evaluating a reform—a single‐topic focus with predistributed briefing materials—designed to enhance deliberative interaction. This reform enhanced effects on opinions of the format without significantly altering effects on attitudes toward the MC. Our results suggest that telephone town halls hold promise for constituents, officeholders, and democratic practice. 相似文献
894.
Neumeyer Xaver Santos Susana C. Morris Michael H. 《The Journal of Technology Transfer》2019,44(2):462-484
The Journal of Technology Transfer - This study attempts to develop our understanding of the ecosystem as a complex social construct by advancing a social network perspective. Based on personal... 相似文献
895.
In recent years, jurisdictions across the United States have expressed a growing interest in aiding criminal investigations through the use of familial DNA searching (FDS)- a forensic technique to identify family members through DNA databases. The National Survey of CODIS Laboratories surveyed U.S. CODIS laboratories about their perceptions, policies, and practices related to FDS. In total, 103 crime labs completed the survey (77% response rate). Labs in 11 states reported using FDS, while labs in 24 states reported using a similar-but distinct- practice of partial matching. Although the majority of labs had positive perceptions about the ability of FDS to assist investigations, labs also reported a number of concerns and challenges with implementing FDS. Respondents reported using either practice a limited amount with modest numbers of convictions resulting from both FDS and partial matching. The article reports on varying practices related to official policies, training, eligibility, the software search, lineage testing, requirements for releasing information, and subsequent investigative work. Finally, the article discusses what can be learned from this survey, accompanying limitations, and implications for decision-makers considering using FDS. 相似文献
896.
897.
Michael Curran Laura Gillespie Sarah Melville Jackie Campbell Bryan Kagan 《Science & justice》2019,59(3):317-321
In forensic intelligence-gathering it would be useful to be able to estimate the size of a perpetrator's foot from a standing bare footprint found at the scene of crime. Currently, the advice is to add a fixed amount to the length of the footprint (typically 1.5 or 2.0 cm), but there is little evidence for this approach. This study used measured footprint and actual foot lengths from 146 participants from the white British student population of a University in the UK. Data were analysed using multiple regression with foot length as the dependent (outcome) variable and footprint length and sex as the independent variable/factor respectively. Sex was not a significant predictor. The regression equation for the best estimate of the foot length is 19.89 + 0.95 × print length ± 8 mm. 相似文献
898.
899.
Asian Journal of Criminology - 相似文献
900.