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Surfmen are thus called young daredevils who climb to the roof of suburban trains in Rio de Janeiro, Brazil and vie with each other in agility and prowess, some of them often falling on the railway tracks and being killed. The practice started as a need to hang on anything outside the crowded train and became a sport of sorts. Even though repressed by the railway authorities and punished by fines and imprisonment, the practice has been going on since the eighties and developed into a competition with rules, code of honour, grading of achievement. It became a means of improving self-esteem as well as securing leadership and social prestige by people who otherwise carry on lives devoid of any charm or ludic stimulus. A substitute behavior, it results from processes of cultural elaboration at work in the youth culture of our cities.  相似文献   
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The purpose of this study was to examine in a sample of 11,516 secondary school students the extent to which different behavioral, emotional and cognitive problems (a) reflected one or more underlying common factors; (b) actually cooccurred; and (c) were single problems. Principal Component Analyses were performed and percentagewise techniques were used. PCA demonstrated that one or more general syndromes could not by far account for all of the variance of the variables. The results suggest the existence of adolescent subgroups with divergent comorbidity patterns: those who primarily report one single symptom; those who report concurrent symptoms either exclusively in the category of behavioral problems or exclusively in the category of emotional and cognitive problems; and those who report concurrent symptoms in both categories. This distinction between different subgroups has important theoretical, diagnostic, and treatment implications.  相似文献   
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Are internalizing and externalizing behavior problems interrelated via mutually reinforcing relationships (with each behavior leading to increases over time in levels of the other behavior) or mutually suppressing relationships (with each behavior leading to decreases over time in levels of the other behavior)? Past research on the directionality of these relationships has led to ambiguous results, particularly in adolescence. Furthermore, the extent to which prior results will generalize to adolescents with low levels of cognitive abilities remains unknown. This second limit is particularly important, given that these adolescents are known to present higher levels of externalizing and internalizing behaviors than their peers with average-to-high levels of cognitive abilities, and that the mechanisms involved in the reciprocal relationships between these two types of behaviors may differ across both populations. This study examines the directionality of the longitudinal relationships between externalizing and internalizing behavior problems as rated by teachers across three measurement waves (corresponding to Grades 8–10) in matched samples of 138 adolescents (34.78?% girls) with low levels of cognitive abilities and 556 adolescents (44.88?% girls) with average-to-high levels of cognitive abilities. The results showed that the measurement structure was fully equivalent across time periods and groups of adolescents, revealing high levels of developmental stability in both types of problems, and moderately high levels of cross-sectional associations. Levels of both internalizing and externalizing behaviors were higher among adolescents with low levels of cognitive abilities relative to those with average-to-high levels of cognitive abilities. Finally, the predictive analyses revealed negative reciprocal longitudinal relationships (i.e., mutually suppressing relationships) between externalizing and internalizing problems, a result that was replicated within samples of adolescents with low, and average-to-high levels of cognitive ability.  相似文献   
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