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141.
Adam Lanzarotta Ph.D. Michael D. Thatcher B.S. Lisa M. Lorenz B.S. JaCinta S. Batson M.S. 《Journal of forensic sciences》2020,65(5):1443-1449
A simple, quick, selective, sensitive, and effective field-friendly method capable of being used by nonexperts has been developed for detecting mitragynine in Mitragyna speciosa (kratom) using surface-enhanced Raman spectroscopy (SERS). Over 100 samples and blanks (known to be either positive or negative for the presence of mitragynine) were examined in duplicate using five identical handheld Raman spectrometers, which provided a data set of over 1,000 examinations. Based on the results of these analyses, the method yielded a true-positive rate of 99.3%, a true-negative rate of 97.9%, a false-positive rate of 2.1%, and a false-negative rate of 0.7%. The average minimum detectable concentration (Cm) of mitragynine that reproducibly yielded a match for one of the library spectra on all five instruments was determined to be 342 ng/mL (ppb). This Cm value is a conservative estimate considering that the extraction process was not fully optimized by this study, which was not necessary since the Cm value achieved was well below typical mitragynine concentrations in kratom (1.3–2.3%). The method is ideal (i) for prioritizing samples for additional testing using other more time-consuming laboratory-based techniques needed to detect and quantify mitragynine and (ii) for field use at international mail facility (IMF) satellite laboratories to help interdict kratom and prevent this dangerous product from reaching the U.S. supply chain. 相似文献
142.
Dominic Gascho R.T. Mária Marosi R.T. Michael J. Thali M.D. Eva Deininger-Czermak M.D. 《Journal of forensic sciences》2020,65(4):1360-1364
Postmortem magnetic resonance imaging (MRI) is rarely used for the radiologic assessment of gunshot injuries, although it has clear advantages over postmortem computed tomography (CT) with regard to the imaging of soft tissue injuries. Another benefit in using MRI is that lodged projectiles composed of nonferromagnetic material such as lead present only marginal metal artifacts compared with severe artifacts on CT. This case report presents CT and MRI findings in a case with two gunshot wounds to the neck: a perforating wound and a nonperforating wound with a lead bullet lodged in the cervical spine. The decedent underwent CT and MRI before the scheduled autopsy. A ring of radiopaque material under the dermis in the fatty tissue was identified at both entrance wounds on CT, which was indicative of contact shots. The perforating gunshot was clearly indicated on CT by bullet fragments along the wound channel through the perforated 6th cervical vertebra and the fractured cricoid cartilage at the exit wound. The second trajectory, however, was only assumed based on the presence of gunshot residues at the entrance wound and the position of the lodged bullet. The radiologic assessment was severely impeded by the metal artifacts on CT. Barely noticeable metal artifacts on MRI allowed for clear visualization of the soft tissue injuries and the ruptured medulla oblongata. Only MRI clarified the soft tissue injuries of the brainstem noninvasively, which could provide specific and graphic information on the rapidity of death and the incapacitation of the victim. 相似文献
143.
This study examined gender differences in cross-gender violence perpetration and victimization (ranging from mild, e.g., push,
to severe, e.g., assault with a knife or gun) and attitudes toward dating conflict, among an urban sample of 601 early adolescents
(78% African-American). Comparisons across gender groups for cross-gender (e.g., female-to-male) violence perpetration and
victimization indicated higher levels of perpetration for girls and higher levels of victimization for boys. Girls also reported
higher levels of verbal and physical violence toward partners with regard to attitudes toward dating conflict. A path model
was specified and indicated that cross-gender violence perpetration, harsh parenting, peer deviance, low family income, and
neighborhood hazards accounted for significant variation in attitudes toward dating conflict. Findings were discussed regarding
the need to identify developmental precursors of dating violence in early adolescence and to focus prevention efforts on components
(e.g., social skills, coping strategies) necessary to prevent the onset and escalation of adolescent dating violence.
相似文献
Sylvie MrugEmail: |
144.
Michael Minkenberg 《West European politics》2018,41(1):53-79
The article presents a comparative analysis of the religious underpinnings of 19 liberal democracies in the West and their relevance for contemporary minority politics. The democratic relevance of religion is conceptualised as stemming from actors (churches, religious parties) and from historical and structural factors such as confessional patterns, relationships between state and church and degrees of secularisation in 19 democracies with a Christian background. The article’s historical mapping demonstrates that democratic development has occurred in distinct patterns rooted in the Catholic?Protestant divide. It then demonstrates that there are distinct effects of this divide on minority politics. It is hypothesised that in line with the confessional patterning of democratisation, Catholic countries and actors seem to be more resistant to the pressures arising from religious pluralisation than Protestant ones and that, even after 9/11, there is no cross-national or cross-confessional convergence in these responses. 相似文献
145.
The investment approach to public service provision is now receiving considerable attention worldwide. By promoting data‐intensive assessments of baseline conditions and how government action can improve on them, the approach holds the potential to transform policy development, service implementation, and program evaluation. Recently, variations on the investment approach have been applied in Australia to explore the effectiveness of specific programs in employment training, criminal justice, and infrastructure development. This article reviews the investment approach, presents a Public Investment Checklist to guide such work, and discusses three examples. It concludes by considering the implications of investment thinking for the work of policy designers and public managers. 相似文献
146.
This article explores the phenomenon of the enduring state control over the Russian natural gas sector. We suggest that explanations of the underlying motives can be classified under two broad theoretical categories: idealism and utilitarianism. Thus, we argue that state capitalism in the Russian natural gas industry can be understood through the idealistic claims of state power and of serving the national interest, which underpin the dominant perception of natural gas resources as a foreign policy tool. Moreover, we contend that although this perception is often considered as a product of the last decade, in fact it is rooted in history, as a legacy of the Soviet era. 相似文献
147.
Show Who the Money? Teacher Sorting Patterns and Performance Pay across U.S. School Districts 下载免费PDF全文
Pay for performance (PFP) remains one of the most controversial policy debates in the New Public Management reform era. Skepticism about PFP in the public sector is often grounded in theories of public service motivation that suggest a misalignment between PFP's focus on extrinsic market‐based pay incentives and intrinsically motivated government workers. Frequently missing from this analysis, however, is any consideration for whether PFP leads to positive “sorting” effects on the composition of a government agency's workforce through attraction, selection, and attrition processes. Using data from two waves of the Schools and Staffing Survey, the authors examine whether PFP influences the sorting patterns of K–12 public schoolteachers across U.S. school districts. Findings show that, on average, school districts that adopted PFP secured new teacher hires who had graduated from colleges and universities with average SAT scores that were about 30 points higher than the new teacher cohorts hired by districts that did not adopt PFP. 相似文献
148.
149.
Michael Kenny 《The Political quarterly》2017,88(4):579-588
Historian, activist and campaigner Edward Thompson is seen as an exemplar of an English radicalism which some see as a lineage with which the contemporary Labour party might fruitfully reconnect. This article examines how Thompson himself understood and characterised the ‘English radical idiom’ and traces his use and then abandonment of this idea in the middle years of his career. It offers some wider reflections about what the insights and lessons associated with his historical writings and reflections on the distinctive nature of English cultural and social thought. 相似文献
150.