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排序方式: 共有854条查询结果,搜索用时 15 毫秒
1.
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   
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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   
3.
Hannah  Adam  Baekkeskov  Erik 《Policy Sciences》2020,53(3):437-452
Policy Sciences - Recent scholarship posits that ambiguous (‘polysemic’) ideas are effective for coalition building between diverse stakeholders: their capacity to be interpreted...  相似文献   
4.
Scholars have long sought to explain the overrepresentation of lawyers in Congress. This article draws on a wealth of data to explore the causes and consequences of this representational imbalance. While lawyers enter politics at higher rates, self-selection at best provides a partial explanation. Conditional on running, lawyers win at twice the rate of candidates from other backgrounds. Contrary to prevailing theories in the literature, voters do not reward candidates with backgrounds in law. Rather, lawyers win because of a sizable competitive advantage in early fundraising, owing in large part to their professional networks. This study has important implications for who runs for office, who wins, and the demographic composition of Congress. It also identifies an underexplored mechanism by which the US system of campaign finance sustains deep representational imbalances.  相似文献   
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FIRST LOVE     
SETH LERER 《耶鲁评论》2010,98(4):39-48
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Correspondence     
Jan Adam 《欧亚研究》1997,49(6):1145-1146
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“I Volunteer to Kidnap Ollie North”, is an exercise in following our government's sometimes criminal, often bizarre and always hypocritical actions in the war on drugs during the Reagan-Bush years to their logical conclusion. The Supreme Court has indicated in its June, 1992 decision in U.S. v Machain, that American law enforcement officers can now enter the sovereign territories of other nations to legally abduct violators of U.S. drug laws. Iran immediately proclaimed that they had the same right for violations of Islamic law. What might happen if kidnapping becomes a recognized “tool” of international law enforcement? What prominent Americans might wake up in South American jails with bags over their heads?  相似文献   
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