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61.
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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ABSTRACT

This paper situates literature on food sovereignty and land reforms in relation to academic and popular writings about land issues in Canada. We argue that settler Canadian food sovereignty scholarship and activism has yet to sufficiently grapple with the implications of private property ownership in relation to ongoing processes of settler colonialism. We also argue that efforts to advance ecologically sustainable farming practices in Canada need to confront private property ownership in terms of its contribution to both capitalist and colonial violence.  相似文献   
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Volatile organic compounds (VOCs) are by-products of cadaveric decomposition and are responsible for the odor associated with decomposing remains. The direct link between VOC production and individual postmortem microbes has not been well characterized experimentally. The purpose of this study was to profile VOCs released from three postmortem bacterial isolates (Bacillus subtilis, Ignatzschineria indica, I. ureiclastica) using solid-phase microextraction arrow (SPME Arrow) and gas chromatography–mass spectrometry (GC-MS). Species were inoculated in headspace vials on Standard Nutrient Agar and monitored over 5 days at 24°C. Each species exhibited a different VOC profile that included common decomposition VOCs. VOCs exhibited upward or downward temporal trends over time. Ignatzschineria indica produced a large amount of dimethyldisulfide. Other compounds of interest included alcohols, aldehydes, aromatics, and ketones. This provides foundational data to link decomposition odor with specific postmortem microbes to improve understanding of underlying mechanisms for decomposition VOC production.  相似文献   
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