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901.
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
902.
Adam Lanzarotta Ph.D. Martin M. Kimani Ph.D. Michael D. Thatcher B.S. John Lynch Ph.D. Moseley Fulcher A.S. Mark R. Witkowski Ph.D. JaCinta S. Batson M.S. 《Journal of forensic sciences》2020,65(4):1274-1279
This study describes the performance of handheld Raman devices for determining whether suspect pharmaceutical tablets declared to contain controlled substances were consistent with authentic (CWA) or not consistent with authentic (NCWA) tablets using a simple, rapid, field-friendly method capable of being used by nonexperts. Twenty-five authentic products and 84 known NCWA tablets were examined using three “parent” devices for a total of 327 analyses. On average, the parent devices yielded a true pass rate of 100%, a true fail rate of 98.4%, a false pass rate of 1.6%, and a false fail rate of 0%. The methods/libraries were then transferred to 13 identical “daughter” devices, which were used to examine 10 suspect finished dosage forms in duplicate (six known NCWA tablets and four authentic tablets) for a total of 260 measurements. On average, the daughter devices had a true pass rate of 100%, a true fail rate of 95.5%, a false pass rate of 4.5%, and a false fail rate of 0.0%. These data demonstrate that the parent–daughter electronic transfer method was successful, which permits the ability to develop methods in the laboratory that can be seamlessly pushed out to field devices. The methods can then be used to (i) prioritize samples for additional testing using other more time-consuming laboratory-based techniques needed to detect and quantify active ingredients and (ii) help support the interdiction of dangerous tablets at ports of entry, thereby preventing them from reaching the supply chain. 相似文献
903.
Journal of Experimental Criminology - Estimate the relationship between race and arrest within co-offending partnerships using a quasi-experimental framework. More specifically, this study argues... 相似文献
904.
905.
Political Behavior - Americans are increasingly turning to social media for political information. However, given that the average social media user only clicks through on a small fraction of the... 相似文献
906.
Greenlee Jill S. Nteta Tatishe M. Rhodes Jesse H. Sharrow Elizabeth A. 《Political Behavior》2020,42(3):655-695
Political Behavior - Throughout her 2016 U.S. presidential campaign, Democratic Party nominee Hillary Clinton crafted messages intended to appeal to fathers of daughters and to highlight the... 相似文献
907.
AbstractThis article analyses party strategies during the campaign for the Dutch general election of March 2017, making use of issue-yield theory. It investigates whether parties strategically emphasise high-yield issues, by juxtaposing the issue opportunities provided by voters with parties’ issue emphasis during the campaign. More specifically, it asks whether parties strategically emphasised issues that were expected to reward them electorally. Analysing voter preferences and party campaign data, it is found that parties and most of their constituencies show high ideological consistency, that parties emphasise mostly positional issues and thus choose a conflict-mobilising strategy, and that most parties emphasise high-yield issues rather than following the general political agenda. Four small parties that won significantly behaved strategically while the social democrats – who severely lost – hardly did. The findings imply that the issue-yield framework can help to explain the election result in the fragmented Dutch multi-party context. 相似文献
908.
Public Choice - Numerous studies—operating with diverse model specifications, samples and empirical measures—suggest different economic, social, cultural, demographic, institutional and... 相似文献
909.
Policy Sciences - Throughout the developing world, payments for ecosystem services (PES) programs are popular policy instruments that allow those who rely on such amenities as drinking water and... 相似文献
910.