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81.
Depression is a common and debilitating disorder in adolescence. Sleep disturbances and depression often co-occur with sleep disturbances frequently preceding depression. The current study investigated whether catastrophic worry, a potential cognitive vulnerability, mediates the relationship between adolescent sleep disturbances and depressive symptoms, as well as whether there are gender differences in this relationship. High school students, ages 16–18, n = 1,760, 49 % girls, completed annual health surveys including reports of sleep disturbance, catastrophic worry, and depressive symptoms. Sleep disturbances predicted depressive symptoms 1-year later. Catastrophic worry partially mediated the relationship. Girls reported more sleep disturbances, depressive symptoms, and catastrophic worry relative to boys. The results, however, were similar regardless of gender. Sleep disturbances and catastrophic worry may provide school nurses, psychologists, teachers, and parents with non-gender specific early indicators of risk for depression. Several potentially important practical implications, including suggestions for intervention and prevention programs, are highlighted.  相似文献   
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Research has long linked academic engagement to positive social, psychological, and physical developmental outcomes; however, qualitative studies in high-performing schools find that some students who work hard in school may be compromising their mental and physical health in the pursuit of top grades. Such research calls for closer and more contextualized examinations of the concept of engagement. This study examines academic engagement in a sample of 6,294 students (54 % female; 44 % White, 34 % Asian, and 22 % other racial or ethnic background) attending 15 high-achieving schools. Findings show that two-thirds of students at these schools are not regularly “fully engaged” in their academic schoolwork; that is, they do not regularly report high levels of affective, behavioral and cognitive engagement. Although most students report working hard, few enjoy their schoolwork and find it valuable. This lack of full engagement, particularly the absence of affective and cognitive engagement, is associated with more frequent school stress, higher rates of cheating, and greater internalizing, externalizing, and physical symptoms of stress. The study also finds that full engagement is strongly related to positive teacher-student relationships. Implications for practice and future research are discussed.  相似文献   
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Experiences with perceived discrimination (e.g., perceptions of being treated unfairly due to race or ethnicity) are expected to impact negatively youths’ prosocial development. However, resilience often occurs in light of such experiences through cultural factors. The current longitudinal study examined the influence of perceived discrimination on the emergence of Mexican American adolescents’ later prosocial tendencies, and examined the mediating role of Mexican American values (e.g., familism, respect, and religiosity). Participants included 749 adolescents (49 % female) interviewed at 5th, 7th, and 10th grade. Results of the current study suggested that, although perceived discrimination was associated negatively with some types of prosocial tendencies (e.g., compliant, emotional, and dire) and related positively to public prosocial helping, the associations were mediated by youths’ Mexican American values. Directions for future research are presented and practical implications for promoting adolescents’ resilience are discussed.  相似文献   
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In the context of rising resource demand, agricultural crops such as sugarcane are being promoted for their multiple uses in different commodity markets and as alternatives to fossil fuel equivalents (i.e. as a source of biofuel, bioelectricity and bioplastic). These commodities are also produced on an increasingly flexible basis, as sugarcane mills respond to price signals and switch between different crop uses. This paper offers a preliminary exploration into the politics of this latest development in the capitalist industrialization of agriculture. It does so by focusing primarily on flexing in Brazil and highlighting the role of the state in both creating markets for non-food products that sugarcane mills can now switch between and managing the tensions that arise from this. These tensions have concerned consumer prices for fuel, control of distribution infrastructure and conditions of land conversion, each prompting political interventions by the state. The paper then suggests how this same process is taking place, albeit shaped by different contexts, in Southern Africa and Cambodia. It concludes with some key questions for further research: is flexing eroding the distinction between crop regimes? How do primary processors decide what their product mix will be? And on what basis do state actors support flexing between agricultural products and investments in so-called bio-refineries?  相似文献   
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Dual-credit courses expose high school students to college-level content and provide the opportunity to earn college credits, in part to smooth the transition to college. With the Tennessee Department of Education, we conduct the first randomized controlled trial of the effects of dual-credit math coursework on a range of high school and college outcomes. We find that the dual-credit advanced algebra course alters students’ subsequent high school math course-taking, reducing enrollment in remedial math and boosting enrollment in precalculus and Advanced Placement math courses. We fail to detect an effect of the dual-credit math course on overall rates of college enrollment. However, the course induces some students to choose four-year universities instead of two-year colleges, particularly for those in the middle of the math achievement distribution and those first exposed to the opportunity to take the course in eleventh rather than twelfth grade. We see limited evidence of improvements in early math performance during college.  相似文献   
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This research note presents three newly interconnected and expanded datasets on interest groups’ (IGs) access to the Swiss political decision‐making process: (1) extra‐parliamentary committee seats occupied by IGs (1980, 2000, 2010), (2) parliamentary (committee) seats occupied by IG representatives (1992‐2015), and (3) consultation replies submitted by IGs (2008‐11). We show that the Swiss system of interest intermediation adapted to the multiplication and organizational consolidation of citizen groups, which defend non‐producer interests and do not provide selective benefits to their members (e.g. environmental groups). The share of access granted to citizen groups has increased in both the administration and parliament, across all federal departments and most legislative committees. Moreover, citizen groups benefit from a larger share of access in the recently revitalized parliament, compared to the administration. This suggests that economic groups’ decline in power is also related to the rise of citizen groups.  相似文献   
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