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We develop a new typology for examination of the effects of international institutions on member states' behavior. Some institutions lead to convergence of members' practices, whereas others result, often for unintended reasons, in divergence. We hypothesize that the observed effect of institutions depends on the level of externalities to state behavior, the design of the institution, and variation in the organization and access of private interests that share the goals of the institution. We illustrate these propositions with examples drawn from international institutions for development assistance, protection of the ozone layer, and completion of the European Union's internal market. We find that significant externalities and appropriately designed institutions lead to convergence of state behavior, whereas divergence can result from the absence of these conditions and the presence of heterogeneity in domestic politics. 相似文献
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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
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Psychological Injury and Law - 相似文献