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41.
Faced with pressing climatic changes, scientific and industrial interests are vying to develop crops that can survive drought, floods and shifting pest regimes. Increasingly, they look for solutions in an unlikely place: the gene pools of wild plants. Crop wild relatives (CWR) – species closely related to crops, including their ancestors – offer breeders the allure of retracing the domestication bottleneck, infusing genomes of modern crops with ‘lost’ genetic variety. Yet wild relatives also confront threats from climate change, urbanization and expansion of industrial agri-food. Thus, CWR, seen as both salvational and threatened, have become an international conservation and food-security priority. It is my contention that, in their common project to harness wild-relative potential, conservation and breeding science are co-evolving to extend seed commodity relations into new spheres. I examine enclosures along two fronts: first within ‘systematic CWR conservation’, where ‘in situ’ approaches, typically regarded as empowering and sustainable alternatives to ‘ex situ’, instead may support a complementary system of value extraction; second, in breeding and biotechnology research, which produces new value for CWR while profoundly shaping upstream conservation priorities. An important finding is that although today’s ‘ex situ-centric’ complementarity favors dispossession, an ‘in situ-centric’ approach could foster democratic renewal of biocultural diversity.  相似文献   
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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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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   
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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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Political Behavior - Americans are increasingly turning to social media for political information. However, given that the average social media user only clicks through on a small fraction of the...  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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