Objective: The stigma toward individuals with mental disorders is highly prevalent, not only in the general population but among health care providers as well. The aim of this study was to identify subgroups based on stigmatizing beliefs related to psychiatric disorders among Brazilian psychiatrists, as well as to investigate their association with clinical and personality characteristics. Methods: Latent cluster analysis was used to find subgroups of cases in multivariate data according to a psychotic (schizophrenia) and a nonpsychotic disorder (attention-deficit hyperactivity disorder). The clusters for each psychiatric disorder were compared according to sociodemographic, emotional traits, and personality characteristics. Results: A total of 779 psychiatrists answered the questionnaire. Three different subgroups of stigma levels were identified regarding schizophrenia: the highest (n=202 [51.7%]), intermediate (108 [27.6%]), and the lowest (81 [20.7%]). Participants from the highest stigma group had a significantly longer time since graduation, higher anxiety-state scores, and lower positive affect. Two subgroups were identified with respect to attention-deficit hyperactivity disorder, although there were no differences between them in sociodemographic or clinical variables. Conclusion: There were more subgroups of stigmatizing beliefs regarding psychotic disorders. Individual characteristics, such as those related to trait anxiety and affect, can be associated with high stigma toward schizophrenia.

Objective: To explore the role of personality traits in at-risk drinking and current cannabis use among medical students. Methods: This cross-sectional study evaluated 707 medical students from two universities. Multiple logistic regression models for at-risk drinking and current cannabis use were constructed including sociodemographic, psychiatric, and personality variables. Results: At-risk drinking and current cannabis use were reported by 19.3% and 14.9% of participants, respectively. Models including Big Five measures showed associations of at-risk drinking with higher extraversion (p < 0.00001, adjusted odds ratio [AOR] = 1.9) and lower conscientiousness (p = 0.00001, AOR = 0.5); cannabis use was also associated with lower conscientiousness (p = 0.003, AOR = 0.6), besides higher openness to experience (p = 0.002, AOR = 1.9). Models including measures of the Behavioral Inhibition and Activation Systems scales (BIS/BAS) showed associations of at-risk drinking with lower BIS (p = 0.002, AOR = 0.9) and higher BAS fun-seeking (p = 0.0005, AOR = 1.2); cannabis use was also associated with higher BAS fun-seeking (p = 0.008, AOR = 1.2). Personality variables had modest effects on model fit. Conclusion: Specific personality traits were independently associated with at-risk drinking and current cannabis use, albeit with modest effect sizes.

Os macroinvertebrados bentônicos exercem a ligação entre a entrada de matéria orgânica nos rios e os peixes. Porém, a possibilidade de influência dos predadores sobre os invertebrados é uma questão ainda controversa. A possibilidade de alteração da comunidade bentônica, pela modificação na predação em um rio no sul do Brasil, foi estudada através de um experimento de exclusão em condições seminaturais. A exclusão resultou no aumento na abundância de Plecoptera no rio onde é feita a introdução de truta arco-íris; as larvas de Trichoptera também aumentaram em abundância nas unidades onde se efetuou a exclusão. Essa diferença não pode ser atribuída à presença das trutas, devido às diferenças na ictiofauna e de habitat dos dois rios. Entretanto mostra a necessidade de desenvolvimento de estudos acerca das relações tróficas e possíveis efeitos desta introdução sobre a biota aquática

Benthic macroinvertebrates constitute the link between organic matter input in streams and fishes. However, the possibility of influence of predators on the invertebrates is still a controversial issue. The possibility of alteration of the benthic community by the modification in predation in a stream in the South of Brazil was studied by means of an exclusion experiment under semi-natural conditions. The exclusion showed an increase in the abundance of Plecoptera in the river where the rainbow trout was introduced, the larvae of Trichoptera also increased in abundance in the units of fish exclusion. This difference does not confirm the pressure applied by the trout on the benthic macro fauna due to differences in ichthyofauna and in the habitat of both rivers. Nevertheless, it points to the need for the development of studies concerning the trophic relations and the possible effects of this introduction in the aquatic biota.