Comportamentos agressivos entre pares e padrões de vinculação : Um estudo com jovens adolescentes

Embora de natureza radicalmente distinta, bullying e vinculação são fenómenos de natureza relacional. Se o bullying é descrito como um abuso sistemático de poder, que ocorre intencional e repetidamente entre pares, a vinculação refere-se ao estabelecimento de laços afectivos fortes com determinadas pessoas significativas, especialmente em momentos percepcionados como perigosos. A investigação, apesar do reduzido número de estudos, mostra uma relação entre estes conceitos. A agressão instrumental interpares parece estar relacionada com vinculações inseguras. O objectivo deste estudo é compreender a relação entre o bullying e os padrões de vinculação. Foi realizado em três escolas da zona de Évora, com os alunos do 7° ano (237 alunos). Utilizaram-se dois questionários de auto-relato: o QEVE - Questionário de Exclusão Social e Violência Escolar e o IVIA - Inventário sobre Vinculação para a Infância e a Adolescência. Os resultados deste estudo corroboram os estudos anteriores, relativamente aos comportamentos agressivos entre pares. Mostram que existem correlações estatisticamente significativas entre as dimensões da vitimação e da agressão e, ainda, verificou-se que a vinculação segura parece funcionar como um factor protector para a vitimação e a agressividade e a vinculação ansiosa parece relacionar-se com a vitimação. ABSTRACT: Although radically different, bullying and attachment are relational in nature phenomena. lf the bullying is described as a systematic abuse of power, which is intentionally and repeatedly between peers, attachment refers to the establishment of strong emotional ties with certain significant others, especially at times perceived as dangerous. The research, despite the small number of studies show a relationship between these concepts. Instrumental peer aggression seems to be associated with insecure attachments. The aim of this study is to understand the relationship between bullying and patterns of binding. lt was conducted in three schools in the district of Évora with the students of 7th Grade (237 students). We used two questionnaires self-report: the QEVE - Questionnaire of Social Exclusion and Violence in School and IVIA - lnventory on Attachment for Children and Adolescents. These results corroborate previous studies, for aggressive behavior among peers. Show that there are statistically significant correlations between the dimensions of victimization and aggression and also found that a secure attachment appears to be a protective factor for victimization and aggression and anxious attachment seems to relate to the victimization.

A multi-component pheromone in the urine of dominant male tilapia (Oreochromis mossambicus) reduces aggression in rivals

Males often use scent to communicate their domi- nance, and to mediate aggressive and breeding behaviors. In teleost fish, however, the chemical composition of male pher- omones is poorly understood. Male Mozambique tilapia, Oreochromis mossambicus, use urine that signals social status and primes females to spawn. The urinary sex pheromone di- rected at females consists of 5β-pregnane-3α,17α,20β-triol 3- glucuronate and its 20α-epimer. The concentration of these is positively correlated with male social rank. This study tested whether dominant male urine reduces aggression in receiver males, and whether the pregnanetriol 3-glucuronates also re- duce male-male aggression. Males were allowed to fight their mirror image when exposed to either: i) water control or a chemical stimulus; ii) dominant male urine (DMU); iii) C18- solid phase (C18-SPE) DMU eluate; iv) C18-SPE DMU eluate plus filtrate; v) the two pregnanetriol 3-glucuronates (P3Gs); or vi) P3Gs plus DMU filtrate. Control males mounted an increas- ingly aggressive fight against their image over time. However, DMU significantly reduced this aggressive response. The two urinary P3Gs did not replicate the effect of whole DMU. Neither did the C18-SPE DMU eluate, containing the P3Gs, alone, nor the C18-SPE DMU filtrate to which the two P3Gs were added. Only exposure to reconstituted DMU (C18-SPE eluate plus filtrate) restored the aggression-reducing effect of whole DMU. Olfactory activity was present in the eluate and the polar filtrate in electro-olfactogram studies. We conclude that P3Gs alone have no reducing effect on aggression and that the urinary signal driving off male competition is likely to be a multi-component pheromone, with components present in both the polar and non-polar urine fractions.