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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   
994.
Prior research has identified a vast number of correlates for delinquent behavior during adolescence, yet a considerable number of errors in prediction remain. These errors suggest that behavioral development among a portion of youths is not well understood, with some exhibiting resilience and others a heightened vulnerability to risks. Examining cases that do not confirm prediction outcomes provides an opportunity to achieve a greater understanding of the relationships between risk factors and delinquency, which can be used to improve theoretical explanations of behavior. This study explores the contribution of genetic and environmental factors to differences in individual responses to cumulative risk for delinquency among a sample of adolescent twins (N = 784 pairs, 49 % female) in the National Longitudinal Study of Adolescent Health. The results indicate that additive genetic and unique environmental factors significantly contribute to variation in responses to cumulative risk across 14 risk factors spanning individual, familial, and environmental domains. When analyzed separately, the majority of the difference between vulnerable youths and the overall population was attributed to genetic influences, while differences between resilient youths and the population were primarily attributed to environmental influences. The findings illustrate the importance of examining both genetic and environmental influences in order to enhance explanations of adolescent offending.  相似文献   
995.
Research indicates that subjective perceptions of socioeconomic status (SES) affect aspects of health and behavior. There has been little research attention to how objective (e.g., education) and subjective aspects of SES may differ in their influence on the substance use of adolescent immigrants. The present study examined whether the associations between subjective SES and substance use, and between parental education and substance use varied by immigrant generation. Data were derived from the 2011 Ontario Student Drug Use and Health Survey, a representative survey of students in the 7th to 12th grade. The sample for this study consisted of 9177 students 12–19 years of age; 48.4 % were female, 66.4 % were White/European, 5.2 % Black/Afro-Caribbean, 16.4 % Asian and 12 % other. Results indicated that subjective SES was more strongly associated with cannabis and alcohol use among first-generation immigrants than among adolescents of other immigrant generations even after adjusting for parental education. First-generation immigrants with low subjective SES had a lower probability of cannabis and regular alcohol use, but there was no difference in use between immigrant generations at high subjective SES. The associations between parental education and cannabis and alcohol use did not significantly vary with immigrant generation. The findings highlight the importance of status beliefs among adolescents, particularly among first-generation immigrants, and suggest that further research attention to such beliefs would enhance our understanding of SES and its links to adolescent health risk behaviors.  相似文献   
996.
Empirical evidence suggests that religiousness is related negatively to adolescent substance use; yet, we know little about how such protective effects might occur. The current study examined whether parents’ and adolescents’ religiousness are associated positively with parental, religious, and self-monitoring, which in turn are related to higher self-control, thereby related to lower adolescent substance use. Participants were 220 adolescents (45 % female) who were interviewed at ages 10–16 and again 2.4 years later. Structural equation modeling analyses suggested that higher adolescents’ religiousness at Time 1 was related to lower substance use at Time 2 indirectly through religious monitoring, self-monitoring, and self-control. Higher parents’ religiousness at Time 1 was associated with higher parental monitoring at Time 2, which in turn was related to lower adolescent substance use at Time 2 directly and indirectly through higher adolescent self-control. The results illustrate that adolescents with high awareness of being monitored by God are likely to show high self-control abilities and, consequently, low substance use. The findings further suggest that adolescents’ religiousness as well as their religious environments (e.g., familial context) can facilitate desirable developmental outcomes.  相似文献   
997.
This article focuses on the degree to which friends’ influence on substance use is conditioned by the consistency between their behavior and that of schoolmates (individuals enrolled in the same school, but not identified as friends), contributing to the literature on the complexity of interactive social influences during adolescence. Specifically, it hypothesizes that friends’ influence will diminish as their norms become less similar to that of schoolmates. The authors also propose that this conditioning relationship is related to the density of the friendship group. This study uses data from the National Longitudinal Survey of Adolescent Health (AddHealth) (n ~ 8,000, 55 % female) to examine the interactive relationship between friend and schoolmate influences on adolescent substance use (smoking and drinking). The sample contains students ranging from age 11 to 22 and is 60 % White. The findings demonstrate that, as the substance use of the friendship group becomes more dissimilar from schoolmates’ substance use, the friendship group’s influence on adolescent substance use diminishes. Further, the results demonstrate that this conditioning relationship does not emerge when the friendship group is highly dense.  相似文献   
998.
Everyday interactions with same-racial/ethnic others may confer positive benefits for adolescents, but the meaning of these interactions are likely influenced by individual differences and larger structural contexts. This study examined the situation-level association between contact with same-ethnic others and anxiety symptoms among a diverse sample of 306 racial/ethnic minority adolescents (Mage = 14 years; 66 % female), based on (1) individual differences in ethnic identity centrality and (2) developmental histories of transitions in diversity between elementary, middle, and high school. The results indicated that at the level of the situation, when adolescents interacted with more same-ethnic others, they reported fewer anxiety symptoms. Further, for adolescents who had experienced a transition in school diversity, the positive benefits of contact with same-ethnic others was only conferred for those who felt that their ethnicity was very important to them. The importance of examining individual differences within larger developmental histories to understand the everyday experiences of ethnic minority adolescents are discussed.  相似文献   
999.
This study presents a number of pseudo-operational trials on plastic bags investigating the double- and co-fuming process of a one-step fluorescent cyanoacrylate (LumicyanoTM) in comparisons with the two-step process with basic yellow 40 (BY40) staining for the detection of latent fingermarks. The results demonstrate that both Lumicyano solution and dye contribute to the increased detection of latent fingermarks during the double-fuming process (trial 1). Co-fuming the Lumicyano solution and dye separately (at a concentration of 8%) but simultaneously was less effective than 8% Lumicyano (trial 2). Co-fuming Lumicyano 8% and an additional 8% Lumicyano dye by weight was more effective than Lumicyano 8% (trial 3), possibly due to increased fluorescent material deposition during co-fuming allowing for better visualization. The use of BY40 after Lumicyano resulted in a considerable increase in detected fingermarks.  相似文献   
1000.
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