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191.
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
192.
193.
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
194.
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
195.
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
196.
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
197.
Using a panel dataset of privatized cement firms in Turkey, this paper models and finds support for the simultaneous relationship between privatization and firm performance. It is found that favorable short-run performance, weak market potential, higher employment, lower socio-economic development, concentrated voter preferences, and weaker representation of right-wing parties in the firms’ locality delay the timing of privatization. The paper also finds that privatization increases output in the medium-term by reducing the labor stock and promoting the adoption of more advanced technology, such that production shifts from constant to decreasing returns to scale. 相似文献
198.
Jay K. Dow 《Political Behavior》2009,31(1):117-136
This study assesses whether gender-based differences in political knowledge primarily result from differences in observable
attributes or from differences in returns for otherwise equivalent characteristics. It applies a statistical decomposition
methodology to data obtained from the 1992–2004 American National Election Studies. There is a consistent 10-point gender
gap in measured political knowledge, of which approximately one-third is due to gender-based differences in the characteristics
that predict political knowledge, with the remaining two-thirds due to male–female differences in the returns to these characteristics.
The methodology identifies the relative contribution of the predictors of political knowledge to each portion of the gap,
and then uses this information to elucidate the underlying sources of the political knowledge gender gap and its prognosis.
Education is the characteristic that most clearly enlarges the gap, with men receiving significantly larger returns to political
knowledge from education than women. Group membership reduces the gap as women obtain gains in political knowledge from belonging
to organizations that do not accrue to men. However, these gains are not sufficient to significantly reduce the gap.
相似文献
Jay K. DowEmail: |
199.
In this paper, we develop and test a general measure of policyexpenditures in the American states. Our approach is to constructa spatial proximity model of yearly state program spending.The empirical analysis reveals that state spending patternsvary along a clear and readily-interpretable unidimensionalcontinuum which differentiates policies that provide particularizedbenefits to needy constituencies from policies that providebroader collective goods. Based upon standard evaluative criteria,the variable created from our model possesses some highly desirablecharacteristics. And, it compares favorably to other measuresof state policy activity. The net result is a yearly score foreach state which summarizes that state's spending across allmajor program areas. More generally, we believe that our variablecan be interpreted as valid and reliable representational measurementof state policy priorities. In this capacity, it could occupyan important position within models of state politics.
Author's note: Many colleagues provided useful feedback on earlierversions of this paper. We particularly appreciate the excellentcomments and suggestions from Robert Erikson, Richard Fording,Kim Hill, David Lowery, Andrea McAtee, and George Rabinowitz.We would also like to thank Daniel Lewis and William Myers fortheir assistance with the data collection. The yearly statepolicy priority scores obtained from the unfolding analysis,along with the data used to create the scores, the SAS macroto carry out the unfolding procedure, and all other supplemental materialsare available on the authors web sites: http://polisci.msu.edu/jacobyand http://polisci.msu.edu/schneider. All these materials arealso available on the Political Analysis Web site. 相似文献
200.