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841.
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   
842.
Thomas  Diana W.  Thomas  Michael D. 《Public Choice》2020,182(3-4):443-457

The Olsonian distinction between roving and stationary bandits outlines the rationale behind the transition from anarchy to the emergence of the predatory state. This two-bandit model may, however, be expanded to include more bandit types. In the case of Viking Age England, local English kings were unable to monopolize violence and defend their realms against competing Viking raiders. As the Vikings’ time horizon grew, so did the accumulated value of more formal taxation, and bandit types evolved in four steps. The first step is the Olsonian roving bandit, who executed Viking hit-and-run attacks and plunders during the second half of the tenth century. The second step is the gafol bandit; gafol is payment for leaving, paid to, among others, Swein Forkbeard. The third step is the heregeld bandit; heregeld is a tax to support an army for hire; most notably Thorkell the Tall’s. The fourth step is the Olsonian stationary bandit, i.e. the strongest military leader among the Vikings, Cnut the Great, settled down as the new king. Overall, the Olsonian two-bandit model can be expanded to a four-bandit staircase model, in which the new gafol and heregeld bandit types explain the steps from anarchy and short-run raiding to long-run formal taxation in a predatory state.

  相似文献   
843.
This paper utilises a qualitative narrative analysis approach to examine smaller foreign investors operating within the Russian agricultural sector as private farmers: the foreign versions of the krestyansko-fermerskiye khoziaistva (peasant farms) that were the early focus of agrarian reform. With difficulty experienced by foreign investment in Russian agriculture, and with the Putin administration shifting its focus to larger scale agriculture, interest lies in the fate of these smaller foreign investors, set in the broader question of: ‘Is there really a future for smaller foreign investors in Russia?’ The investors were aligned along a performance and narrative spectrum, and the construction of their identities – guided by their adaptive processes on the ‘Turnerian’ frontier – were found to shape their business conduct, and interactions with labour forces and regional authorities. Negative prejudgment of the labour force existed amongst the investors – with associated negative notions of trust, inefficiency, laziness, morality, and sexual deviancy – and they were involved in explicit or ambiguous forms of gift-gifting, drawing parallels to Soviet blat behaviour. This paper concludes that despite efforts to construct identity, the narratives of the investors betrayed themselves in certain aspects, with elements of ‘undoing’ in the identity process.  相似文献   
844.
This study used data from a sample of 6th to 12th grade students (N = 48,641, 51% female), nested in 192 schools, to determine if the influence of family-based protective factors varied across different school contexts. Hierarchical logistic regression models were used to examine the effects of individual-level family protective factors, relative to school-level aggregates of the same factors, on recent (past 30 days) use of cigarettes, alcohol, and marijuana. Cross-level interactions indicated that the effect of the student’s level of family protection, relative to other students in their school, differed depending on the aggregated school level of family protection. The results suggested that the benefit of belonging to a well-functioning family was more influential for students attending schools characterized by higher-than-average aggregated levels of protection compared to students attending schools of lower-than-average protection. Thus, family-level factors offered less protection for students in relatively high-risk school contexts. These results were consistent with a protective–reactive interaction and suggest that a thorough understanding of adolescent substance use must consider the complex interplay among adolescents, their families, and their social environments.  相似文献   
845.
Underage drinking is among the most serious of public health problems facing adolescents in the United States. Recent concerns have centered on young women, reflected in media reports and arrest statistics on their increasing problematic alcohol use. This study rigorously examined whether girls’ alcohol use rose by applying time series methods to both arrest data, Uniform Crime Reports, and self-report data from Monitoring the Future, a nationally representative long-term survey gathered independently of crime control agents. All self-reported drinking behaviors across all age groups show declining or unchanged female rates and no significant change in the gender gap, while the official source displays a steady narrowing gender gap and some increase of female arrest rates for liquor law violations. Results indicate that social control measures applied to underage drinking have shifted to target young women’s drinking patterns, but their drinking has not become more widespread/problematic. Girls’ increased alcohol use and abuse is a socially constructed problem, rather than the result of normalization of drinking or more strain in girls’ lives. Future underage drinking policies and practices that apply legal intervention strategies to less chronic adolescent drinking behaviors will increase the visibility of girls’ drinking.  相似文献   
846.
Latinas in the United States are at a disproportionate risk for STDs and sexual risk behaviors. Among Latinas, acculturation has been found to be one of the most important predictors of these behaviors. Therefore, this study examined the longitudinal association between Latina adolescents’ level of acculturation and multiple sexual risk outcomes, including self-report STD diagnosis, four or more life-time sex partners, regret of sexual initiation after alcohol use, and lack of condom use during young adulthood. Based on the National Longitudinal Study of Adolescent Health (Add Health), this study includes a nationally representative sample of 1,073 Latina adolescents (ages 11–20 at Wave 1) transitioning into young adulthood (ages 18–27 at Wave 3). Our findings indicate that more acculturated Latinas who spoke English at home were more likely to have STDs and to exhibit sexual risk behaviors than Latinas who were foreign-born and did not use English at home. Interventions that aim to promote sexual and reproductive health among young Latinas should take into consideration their different levels of acculturation. This approach holds greater potential for reducing health disparities among Latinas.  相似文献   
847.
Previous findings have shown both beneficial and adverse effects of parents’ attempts to influence adolescents’ eating habits. The current study examined the differential effect of parents’ persuasion (e.g., encouragement, giving information) and pressure tactics (e.g., guilt induction, ridicule) and the moderating influence of parental warmth on older adolescents’ emotional and behavioral responses. An ethnically diverse sample of 336 older adolescents (M age = 18.6; SD = 1.1; 58.0% female) were surveyed. Adolescents who reported higher levels of pressure tactics by parents reported more negative affect and behavioral resistance. Perceived parental warmth moderated the influence of persuasion tactics, but not pressure tactics. For adolescents with low parental warmth, high levels of persuasion were associated with more negative emotional and behavioral responses; persuasion had the opposite associations for adolescents with high parental warmth. These results suggest that parental warmth plays an important role in how older adolescents respond to parents’ persuasion tactics. However, when parents use more forceful pressure tactics to influence eating habits, adolescents react negatively regardless of the overall quality of the parent–adolescent relationship.  相似文献   
848.
The purpose of the present study was to examine relations between adolescents’ social cognitions regarding parenting practices and adolescents’ prosocial behavioral tendencies. A mediation model was tested whereby the degree to which adolescents perceived their parents as responding appropriately to their prosocial and antisocial behaviors was hypothesized to predict adolescents’ tendencies toward prosocial behavior indirectly by way of adolescents’ prosocial values. Adolescents (N = 140; M age = 16.76 years, SD = .80; 64% girls; 91% European Americans) completed measures of prosocial values and of the appropriateness with which they expected their parents to react to their prosocial and antisocial behaviors. In addition, teachers and parents rated the adolescents’ tendencies for prosocial behaviors. A structural equation model test showed that the degree to which adolescents expected their parents to respond appropriately to their prosocial behaviors was related positively to their prosocial values, which in turn was positively associated with their tendencies to engage in prosocial behaviors (as reported by parents and teachers). The findings provide evidence for the central role of adolescents’ evaluations and expectancies of parental behaviors and of the role of values in predicting prosocial tendencies. Discussion focuses on the implications for moral socialization theories and on the practical implications of these findings in understanding adolescents’ prosocial development.  相似文献   
849.
Studies using valid measures of monitoring activities have not found the anticipated main effects linking greater monitoring activity with fewer behavioral problems. This study focused on two contexts in which monitoring activities may be particularly influential. Early adolescents (n = 218, M age = 11.5 years, 51% female, 49% European American, 47% African American) reported their unsupervised time, beliefs about the legitimacy of their parents’ authority, and their own involvement in antisocial behavior. Mothers and adolescents reported their perceptions of adolescent disclosure and parental solicitation and control. Adolescents’ perceptions of greater parental solicitation at age 11 were associated with less antisocial behavior at age 12 (when controlling for age 11 antisocial behavior) among adolescents reporting large amounts of unsupervised time and weak legitimacy beliefs. Perceived parental solicitation may be an effective deterrent of antisocial behavior when adolescents spend a lot of time unsupervised and for adolescents who are likely to challenge the legitimacy of their parents’ authority.  相似文献   
850.
While having a purpose in life has been theorized as a developmental asset, the extent to which adolescents cultivate a meaningful sense of direction is not well understood. In the present study, cluster analysis was used to classify adolescents by levels of purpose exploration and commitment. The sample (N = 318; 55% female) consisted of youth aged 14–18 and was predominantly White/non-Hispanic (76.3%). Results supported four meaningful yet distinguishable profiles of youth purpose that are largely consistent with theories on identity formation: Achieved, Foreclosed, Uncommitted, and Diffused. Hypothesized linkages with affect and hope were established across the profiles such that positive emotions and goal-directed thinking were most apparent among Achieved and Foreclosed youth and least apparent among Diffused and Uncommitted youth. Overall, findings demonstrate the inherent complexity in adolescents’ engagement with purpose and suggest a correspondence between stronger commitments to purpose and youths’ sense of personal agency and well-being.  相似文献   
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