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Journal of Youth and Adolescence - Theory and research indicate considerable changes in parental control across adolescence (e.g., declining behavioral control), but the developmental course and...  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   
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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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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   
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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   
27.
Contemporary urbanization in the Global South merits greater attention from scholars of comparative politics. Governance, associational life, and political behavior take distinctive forms in the social and institutional environments created by rapid urbanization, particularly within informal settlements and labor markets. In this special issue, we examine forms of collective action and claims-making in these spaces. We also consider how the state assesses, maps, and responds to the demands of informal sector actors. Tackling questions of citizen and state behavior in these informal urban contexts requires innovative research strategies due to data scarcity and social and institutional complexity. Contributors to this symposium offer novel strategies for addressing these challenges, including the use of informal archives, worksite-based sampling, ethnographic survey design, enforcement process-tracing, and crowd-sourced data.  相似文献   
28.
Justice-involved youth have high rates of psychiatric diagnoses, and these youth are often placed out-of-home, although evidence identifies several negative implications of juvenile confinement, especially for youth with psychopathology. Furthermore, youth in the justice system may be processed differently based on gender. As males and females tend to manifest symptoms differently, the psychopathology of youth may act to moderate the relationship between gender and placement in the juvenile justice system. The present study used a large, diverse sample (n?=?9?851, 19.8?% female) to examine whether youth placed in various types of out-of-home facilities differed in terms of externalizing, internalizing, substance use, or comorbid disorders, and to determine the predictive value of mental health diagnoses in placement decisions. The moderation effect of psychopathology and substance use on the relationship between gender and placement also was explored. The results indicated that each type of disorder differed across placements, with internalizing being most prevalent in non-secure, and externalizing, comorbid, and substance use being most prevalent in secure settings. Mental health diagnoses improved the prediction of placement in each out-of-home placement beyond legal and demographic factors such that externalizing and substance use disorders decreased the likelihood of placement in non-secure settings, and internalizing, externalizing, and substance use disorders increased the likelihood of placement in secure and state-secure facilities. The relationship between internalizing pathology and placement in more secure facilities was moderated by externalizing pathology. The relationship between gender and placement was significantly moderated by mental health such that females with mental health diagnoses receive less secure placements. Implications for policymakers and practitioners are discussed, as well as implications for reforming juvenile justice within a developmental approach.  相似文献   
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This paper asks whether strong bureaucracies can effectively constrain the continuously growing stock of rules in modern democracies through organizational coordination and learning. To answer this question, the paper analyzes the growth of rule stocks in the areas of environmental policy and social policy in 23 OECD countries over the period between 1976 and 2005. To do so, it develops a new measure of rule growth based on the content of laws and regulations rather than their length. The analysis highlights that effective bureaucracies are indeed better able to contain rule growth in these areas than weak bureaucracies. Since rules have to be implemented, countries suffering from bureaucratic capacity and quality constraints thus appear to be stuck in an implementation deficit trap. Appropriate implementation is not only inherently more challenging for countries with weak public administrations, but the body of rules to be implemented also tends to grow quicker in these countries.  相似文献   
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