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41.
Although the relation between family relationships and the timing of sexual debut has been the focus of many studies, research on mediating factors is scarce. This study examines whether low levels of family cohesion result in an earlier onset of romantic and sexual experiences, and whether the link between family cohesion and an early sexual debut is mediated by early romantic initiation. A longitudinal sample of 314 adolescent girls and 222 boys, aged 12–17 at Wave 1, completed questionnaires at three measurement points with three year intervals. The results showed that sexual debut followed romantic initiation for 77% of the participants. For early adolescent females (aged 12–14), high levels of family cohesion resulted in a later sexual debut and this association was fully mediated by a delay of romantic initiation. Among boys and older girls, timing of romantic initiation did not mediate the link between family cohesion and timing of sexual initiation. Early adolescent girls who have negative relationships with their parents turn to romantic relationships for intimacy and support, which subsequently provide the opportunity for an early sexual debut. Low levels of family cohesion thus primarily precipitate romantic initiation and sexual initiation appears to be secondary to this process among girls in this age group.  相似文献   
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The United States Supreme Court’s recent decision relating to violent video games revealed divisions within the scientific community about the potential for negative effects of such games as well as the need for more, higher quality research. Scholars also have debated the potential for violent games to have positive effects such as on visuospatial cognition or math ability. The current study sought to extend previous literature by using well-validated clinical outcome measures for relevant constructs, which have generally been lacking in past research. Cross-section data on aggression, visuospatial cognition, and math achievement were available for a sample of 333 (51.7 % female) mostly Hispanic youth (mean age = 12.76). Prospective 1-year data on aggression and school GPA were available for 143 (46.2 % female) of those youth. Results from both sets of analysis revealed that exposure to violent game had neither short-term nor long-term predictive influences on either positive or negative outcomes. A developmental analysis of the cross-sectional data revealed that results did not differ across age categories of older children, preadolescents or adolescents. Analysis of effect sizes largely ruled out Type II error as a possible explanation for null results. Suggestions for new directions in the field of video game research are proffered.  相似文献   
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Food production has been changing significantly in recent years as a result of climate change and of growing demand for food. This article aims to understand the link between food security and international security in the context of climate change, applying a systematic and qualitative analysis of the literature using the bibliometric method. This research observes that climate change tends to affect agricultural productivity, exposing societies to risk and the need for migration. However, good governance, together with international cooperation, can reduce the hazards of food insecurity, strengthening ties between countries and stimulating a fairer and more inclusive form of international trade.  相似文献   
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The pandemic of Covid-19 has exposed the veins of inequality in Latin America. With a socioeconomic disaster looming, social emergency policies seemed inevitable. Yet while governments argue over the continuity of such policies and whether the fiscal rules in place should be respected, no sustainable response has come out. This essay problematises whether the pandemic could represent a critical juncture to forge ahead with political narratives that highlight tax exemptions and privileges enjoyed by the rich. We analyse the mitigation measures adopted by Argentina, Brazil, Chile and Uruguay and their repercussions on the debate surrounding progressive tax reforms to fund social schemes.  相似文献   
47.
DNA is one of the fastest growing tools in forensic sciences, increasing reliability in forensic reports and judgments. The use of DNA has increased in different areas of the forensic sciences, such as investigation of plant species, where plastid DNA has been used to elucidate and generate evidence in cases of traceability of genetically modified and controlled plants. Even with several advances and the practice of using DNA in forensic investigations, there are just few studies related to the identification of genetic tools for the characterization of drug and nondrug-types of Cannabis. Herein, the whole plastomes of two drug-type Cannabis are presented and have their structures compared with other Cannabis plastomes deposited in the GenBank, focusing in the forensic use of plastome sequences. The plastomes of Cannabis sativa “Brazuka” and of the hybrid Cannabis AK Royal Automatic presented general structure that does not differs from the reported for other C. sativa cultivars. A phylogenomic analyses grouped C. sativa “Brazuka” with the nondrug C. sativa cultivars, while the hybrid Cannabis AK Royal Automatic placed isolated, basal to this group. This suggests that the analysis of plastomes is useful toward genetic identification of hybrids in relation to C. sativa.  相似文献   
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Empathy, which is the ability to feel concern for and to understand others’ feelings, is thought to develop in high quality relationships with parent and peers, but also to facilitate the quality of these relationships. While a wide literature has addressed this aspect, the heterogeneity of primary studies, in which different indicators of relationship quality (e.g., support, conflict) and empathy (i.e., affective and cognitive) have been examined, makes it difficult to draw conclusive answers. Therefore, it remained ambiguous how parent–child and peer relationship quality are associated with adolescents’ empathy. In order to increase the understanding of these associations, a multilevel meta-analysis was performed, which allowed for including multiple effect sizes from each study. By a systematic literate search, 70 eligible studies were found that provided 390 effect sizes from 75 independent samples. The results showed a small positive correlation between parent–child relationship quality and empathy, and a small-to-moderate positive correlation between peer relationship quality and empathy, which was significantly stronger than the correlation with parent–child relationship quality. Hence, the meta-analytic results indicate that adolescents with higher quality relationships, especially with peers, indeed tend to show more concern for and understanding of others’ emotions than adolescents with lower quality relationships. Moreover, the moderation analyses showed stronger correlations for the positive dimension of relationship quality than for the negative dimension, and stronger correlations for composite scores of affective and cognitive empathy than for separate scores of the empathy dimensions. However, no differences in correlations were found between the affective and cognitive empathy dimension, and no moderation effects were found for gender and age. Thus, this meta-analysis demonstrates robust positive associations between parent–child and peer relationship quality and empathy in adolescence, implying that good empathic abilities may be a protective factor for experiencing poor relationships.

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50.
In response to ongoing plant genetic enclosures, the Open Source Seed Initiative (OSSI) is creating a ‘protected commons’ for seed. It is a project, I argue, that reflects characteristics of a growing transnational commoning movement. From the Zapatistas to seed wars, such movements draw attention to commons not simply as a resource, but as a dynamic and evolving social activity: commoning. In the US, OSSI includes 38 plant breeders, 48 seed companies and 377 crop varieties. Yet challenges remain for OSSI to gain wider legitimacy for ‘freed seed’, to build trust in a moral pledge, and to establish fair guidelines for which people and which seed can participate in making the commons. Using the metaphor of ‘beating the bounds’ – a feudal practice of contesting enclosures – I ask how OSSI defends the commons in intersecting arenas. The first way is legal, as OSSI negotiates a move from contract law toward moral economy law. Next is epistemic, as an informal breeder network revitalizes farmer knowledge, while proving more structurally able and culturally equipped to lead commoning efforts. Finally, I reflect on the nature of boundary beating itself, aided by Global South movements. Seed sovereignty perspectives suggest room for a pluriverse of commons to grow.  相似文献   
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