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181.
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   
182.
Suicide is a leading cause of death among adolescents, many of whom fail to disclose suicide concerns to adults who might help. This study examined patterns and predictors of help-seeking behavior among adolescents who seriously considered suicide in the past year. 2,737 students (50.9?% female, 46.9?% male; racial distribution 79.5?% Caucasian, 11.9?% Hispanic/Latino, and 3.6?% Black/African-American) from 12 high schools in rural/underserviced communities were surveyed to assess serious suicide ideation (SI) in the past year, disclosure of SI to adults and peers, attempts to get help, attitudes about help-seeking, perceptions of school engagement, and coping support. Help-seeking was defined as both disclosing SI to an adult and perceiving oneself as seeking help. The relationship between adolescents' help-seeking disclosure and (1) help-seeking attitudes and (2) perceptions of social resources was examined among suicidal help-seeking youth, suicidal non-help-seeking youth, and non-suicidal youth. Of the 381 (14?%) students reporting SI, only 23?% told an adult, 29?% sought adult help, and 15?% did both. Suicidal help-seekers were similar to non-suicidal peers on all measures of help-seeking attitudes and social environment perceptions. Positive attitudes about help-seeking from adults at school, perceptions that adults would respond to suicide concerns, willingness to overcome peer secrecy requests, and greater coping support and engagement with the school were associated with students' increased disclosure of SI and help-seeking. This study supports prevention strategies that change student norms, attitudes and social environments to promote help-seeking among adolescents with SI. Promising intervention targets include increasing students' perceptions of the availability and capability of adults to help them, and strengthening students' understanding of how existing resources can help them cope.  相似文献   
183.
This article argues that if the introduction of genetically modified crops (GM crops) in developing countries is to be successful, we can and should not evade questions of access and control of technology. It implies probing into the experiences, perceptions and understanding of GM crops by the prime user: the farmer. Exactly in these respects the scholarly literature is remarkably silent. We know little about farmers' experiences and perceptions of GM crops' potential risks and benefits. This is evident when concentrating on a major GM crop – Bt cotton – and studying this in the context of China, its second largest producer in the world. Based on the results of a large survey, we demonstrate that Chinese farmers' awareness (‘having heard of’) and their understanding (‘being able to explain’) of Bt cotton is low. This may lead to ill-informed, distorted risk perceptions and a general inability to relate agricultural production problems to the specific nature of transgenic cotton cultivation. A great majority of the farmers find that the Chinese seed market was liberalised too early, in turn leading to a high incidence of ‘stealth transgenics’ or illegal seeds, the undermining of farmers' trust in private institutions, and a weakened biosafety regime. This finding points to the need for continued state intervention in the seed market, particularly in a developing context. Finally, we have discovered that farmers report a significantly lower reduction in pesticide use by Bt cotton than found in other studies. As suggested by recent research, we suspect that the higher pesticide use is necessary to control secondary pests – i.e. pests other than the cotton bollworm. We present empirical evidence that Chinese farmers perceive a substantive increase in secondary pests after Bt cotton was introduced.  相似文献   
184.
Agroecology has played a key role in helping Cuba survive the crisis caused by the collapse of the socialist bloc in Europe and the tightening of the US trade embargo. Cuban peasants have been able to boost food production without scarce and expensive imported agricultural chemicals by first substituting more ecological inputs for the no longer available imports, and then by making a transition to more agroecologically integrated and diverse farming systems. This was possible not so much because appropriate alternatives were made available, but rather because of the Campesino-a-Campesino (CAC) social process methodology that the National Association of Small Farmers (ANAP) used to build a grassroots agroecology movement. This paper was produced in a ‘self-study’ process spearheaded by ANAP and La Via Campesina, the international agrarian movement of which ANAP is a member. In it we document and analyze the history of the Campesino-to-Campesino Agroecology Movement (MACAC), and the significantly increased contribution of peasants to national food production in Cuba that was brought about, at least in part, due to this movement. Our key findings are (i) the spread of agroecology was rapid and successful largely due to the social process methodology and social movement dynamics, (ii) farming practices evolved over time and contributed to significantly increased relative and absolute production by the peasant sector, and (iii) those practices resulted in additional benefits including resilience to climate change.  相似文献   
185.
186.
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   
187.
The purpose of this article is to explain how public managers can influence the mix of institutional logics in a process of organizational change. To do this, the concept of post-transformational leadership is related to institutional logics. The article is based on a case study of the Danish Crime Prevention Council. The study shows how post-transformative leaders are urged to move from strategies of collaboration to strategies of manipulation, hypocrisy, and the hijacking of institutional logics.  相似文献   
188.
There is limited research that has examined experimentally the effects of muscular images on adolescent boys’ body image, with no research specifically examining the effects of music television. The aim of the current study was to examine the effects of viewing muscular and attractive singers in music video clips on early, mid, and late adolescent boys’ body image, mood, and schema activation. Participants were 180 boys in grade 7 (mean age = 12.73 years), grade 9 (mean age = 14.40 years) or grade 11 (mean age = 16.15 years) who completed pre- and post-test measures of mood and body satisfaction after viewing music videos containing male singers of muscular or average appearance. They also completed measures of schema activation and social comparison after viewing the clips. The results showed that the boys who viewed the muscular clips reported poorer upper body satisfaction, lower appearance satisfaction, lower happiness, and more depressive feelings compared to boys who viewed the clips depicting singers of average appearance. There was no evidence of increased appearance schema activation but the boys who viewed the muscular clips did report higher levels of social comparison to the singers. The results suggest that music video clips are a powerful form of media in conveying information about the male ideal body shape and that negative effects are found in boys as young as 12 years.  相似文献   
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190.
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