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231.
Sheila K. Marshall Lauree C. Tilton-Weaver Håkan Stattin 《Journal of youth and adolescence》2013,42(8):1234-1242
Previous research has shown a consistent positive association between non-suicidal self-injury and depressive symptoms. However, the direction of the effects has not been examined. To understand whether non-suicidal self-injury predicts depressive symptoms or vice versa, we examined the relations between non-suicidal self-injury and depressive symptoms across three waves of self-report data collected 1 year apart from 506 Swedish adolescents (47 % girls; M age = 13.21; SD = .57) who were attending 7th grade at the onset of the study. The results suggest that depressive symptoms predict increases in non-suicidal self-injury 1 year later between the first and second waves of the study. Between the second and third waves of the study depressive symptoms and non-suicidal self-injury were significantly correlated indicating co-occurrence with no direction of effect rather than depressive symptoms predicting non-suicidal self-injury or vice versa. Group comparisons revealed no differences for boys and girls. The findings help clarify the relationships between non-suicidal self-injury and depressive symptoms during middle adolescence. 相似文献
232.
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
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