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221.
Alex J. Krotulski M.S.F.S. Susan Jansen Varnum Ph.D. Barry K. Logan Ph.D. 《Journal of forensic sciences》2020,65(2):550-562
Novel psychoactive substances (NPS) are synthetic drugs that pose serious public health and safety concerns. A multitude of NPS have been identified in the United States, often implicated in forensic investigations. The most common and effective manner for identifying NPS is by use of mass spectrometry and the true utility lies within nontargeted acquisition techniques. During this study, a liquid chromatography quadrupole time-of-flight mass spectrometry (LC-QTOF-MS) assay was developed, validated, and implemented for forensic toxicology testing. A SCIEX TripleTOF™ 5600 + with SWATH® acquisition was used. Resulting data were compared against an extensive library database containing more than 800 compounds. The LC-QTOF-MS assay was applied to the reanalysis of biological sample extracts to discover emergent NPS. More than 3,000 sample extracts were analyzed, and more than 20 emerging NPS were detected for the first time. Among these were isopropyl-U-47700, 3,4-methylenedioxy-U-47700, fluorofuranylfentanyl, N-methyl norfentanyl, 2F-deschloroketamine, 3,4-methylenedioxy-alpha-PHP, eutylone, and N-ethyl hexedrone. 相似文献
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223.
Levey Emma K. V. Garandeau Claire F. Meeus Wim Branje Susan 《Journal of youth and adolescence》2019,48(6):1068-1081
Journal of Youth and Adolescence - Adolescence tends to be characterized by a temporary peak in delinquent behavior, and friends in particular play a key role in the initiation and the development... 相似文献
224.
Journal of Youth and Adolescence - Dual identity (e.g., strong ethnic and national identity) is a psychological resource for minority groups, but how it develops during adolescence is less clear.... 相似文献
225.
This article explores the construction of extremism in media discourse, the factors driving specific constructions and the implications of these constructions for counterterrorism policy. We contend that extremism has predominantly and increasingly been framed as a security issue. This article explores the implications of this practice through the framework of securitisation. We measure the average intensity of security framing in 38,616 articles found in three major US newspapers, New York Times, Wall Street Journal and Los Angeles Times, between 20 January 1993 and 19 January 2017 comprising the Clinton, Bush and Obama presidencies, and look at factors influencing the shift in intensity over time. Through our analysis, we show that it is possible to return to a pre-9/11 discourse but that the confluence of real-world events and the strategic choices of political actors have so far prevented this from fully occurring. We then explore the effect of securitisation on public perceptions of the threat from terrorism, finding that increases in the intensity of security framing artificially increases the public’s worry about becoming a victim of terrorism. We conclude by discussing implications for the communication of counterterrorism policy and the requirements for an after, after 9/11 approach 相似文献
226.
ABSTRACTThis article analyses how the presence of a dominant group of voters within the electorate affects voter turnout. Theoretically, we argue that its absolute size affects turnout via increased free-riding incentives and reduced social pressure to vote within a larger dominant group. Its relative size compared to other groups within the electorate influences turnout through instrumental and expressive responses – in both the dominant and dominated groups – to the degree of electoral competition between groups. Empirical evidence from a large cross section of German municipalities is in line with these theoretical predictions. The observed effects should be taken into account when redesigning electoral jurisdictions through, for instance, municipal mergers or gerrymandering. 相似文献
227.
Edmond P. Bowers Yibing Li Megan K. Kiely Aerika Brittian Jacqueline V. Lerner Richard M. Lerner 《Journal of youth and adolescence》2010,39(7):720-735
The understanding of positive development across adolescence rests on having a valid and equivalent measure of this construct across the breadth of this period of life. Does the Positive Youth Development (PYD) construct based on the Five Cs model have satisfactory psychometric properties for such longitudinal measurement invariance? Using longitudinal data derived from the 4-H Study of PYD, we assessed 920 youth (61.6% female) from a racially and ethically diverse sample (67.3% European American) who participated in three waves (Grades 8–10) of data collection. Building on prior findings that the Five Cs (i.e., Competence, Confidence, Connection, Character, and Caring) model of PYD was a robust measure that could be assessed comparably during early adolescence, we tested a hierarchy of second-order confirmatory factor analysis models to assess the extent to which PYD can be measured equivalently across middle adolescence. Evidence was found for strict measurement invariance across three measurement occasions, including equivalence of first-order and second-order factor loadings, equality of intercepts of observed variables, and equality of item uniqueness and disturbances of the first-order factors. These results suggest that PYD can be measured in the same way across measurement occasions, a prerequisite for the study of development. Implications for research and application of being able to measure PYD equivalently across adolescence are discussed. 相似文献
228.
While the financial crisis of 2008 ultimately affected the range of U.S. financial institutions, it began with practices in home ownership finance. The Federal Home Loan Bank (FHLBank) System was the first instrumentality created by the U.S. government, in 1932, to sustain affordable home ownership finance. In this article, the authors ask what role, if any, the FHLBanks played in the subprime lending and securitization practices that precipitated the current crisis. The authors analyze publicly available FHLBank financial data in terms of a framework focused on the System's assets: advances; mortgage loans acquired from members; and investments, particularly in mortgage-backed-securities. They conclude that the FHLBanks did not contribute significantly to problematic practices. Nonetheless, they recommend consideration of three reforms to the FHLBanks to ensure a return to effective regulation and responsible, affordable home ownership finance. 相似文献
229.
Oscar W. Gabriel Ulf Bohmann Daniel Gaus Emanuel Richter Annika Frisch Helga Haftendorn Dirk Berg-Schlosser Frank Bönker Dennis-Jonathan Mann Christian Tuschhoff Karsten Schmitz Jared Sonnicksen Heinrich Pehle Marco Schäferhoff Wilhelm Bleek Jürgen Petersen 《Politische Vierteljahresschrift》2009,50(3):646-690
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