Mandibular gland secretions of meliponine worker bees: further evidence for their role in interspecific and intraspecific defence and aggression and against their role in food source signalling

Like ants and termites some species of stingless bees (Meliponini), which are very important pollinators in the tropics, use pheromone trails to communicate the location of a food source. We present data on the communicative role of mandibular gland secretions of Meliponini that resolve a recent controversy about their importance in the laying of such trails. Volatile constituents of the mandibular glands have been erroneously thought both to elicit aggressive/defensive behaviour and to signal food source location. We studied Trigona spinipes and Scaptotrigona aff. depilis (`postica`), two sympatric species to which this hypothesis was applied. Using extracts of carefully dissected glands instead of crude cephalic extracts we analysed the substances contained in the mandibular glands of worker bees. Major components of the extracts were 2-heptanol (both species), nonanal (T. spinipes), benzaldehyde and 2-tridecanone (S. aff. depilis). The effect of mandibular gland extracts and of individual components thereof on the behaviour of worker bees near their nest and at highly profitable food sources was consistent. Independent of the amount of mandibular gland extract applied, the bees overwhelmingly reacted with defensive behaviour and were never attracted to feeders scented with mandibular gland extract or any of the synthetic chemicals tested. Both bee species are capable of using mandibular gland secretions for intra-and interspecific communication of defence and aggression and share 2-heptanol as a major pheromone compound. While confirming the role of the mandibular glands in nest defence, our experiments provide strong evidence against their role in food source signalling.

Tradução e adaptação cultural da Management of Aggression And Violence Attitude Scale – MAVAS – em enfermeiros brasileiros

Este estudo objetivou traduzir e adaptar culturalmente a Management of Aggression and Violence Attitude Scale – MAVAS – para uso no Brasil. As etapas metodológicas seguiram as diretrizes internacionais para adaptação cultural de escalas psicométricas: equivalência conceitual, equivalência semântica, equivalência de itens e equivalência operacional. A validade de conteúdo realizada por um grupo de juízes resultou numa escala composta por 23 itens divididos em quatro fatores com Coeficientes de Validade de Conteúdo (CVC) satisfatórios nos parâmetros avaliados: (0,88) para clareza de linguagem, 0,91 pertinência prática e 0,92 para relevância teórica. Os dados foram coletados no ano de 2011, em Londrina, PR, Brasil. Concluiu-se que a MAVAS-BR está traduzida e adaptada culturalmente para uso no Brasil e que o instrumento traduzido e adaptado apresenta validade de conteúdo satisfatória. Estudos futuros relacionados à MAVAS-BR são sugeridos, dentre eles a avaliação de suas qualidades psicométricas, como a validade de construto e a confiabilidade do instrumento.

Sex ratio bias, male aggression, and population collapse in lizards.

The adult sex ratio (ASR) is a key parameter of the demography of human and other animal populations, yet the causes of variation in ASR, how individuals respond to this variation, and how their response feeds back into population dynamics remain poorly understood. A prevalent hypothesis is that ASR is regulated by intrasexual competition, which would cause more mortality or emigration in the sex of increasing frequency. Our experimental manipulation of populations of the common lizard (Lacerta vivipara) shows the opposite effect. Male mortality and emigration are not higher under male-biased ASR. Rather, an excess of adult males begets aggression toward adult females, whose survival and fecundity drop, along with their emigration rate. The ensuing prediction that adult male skew should be amplified and total population size should decline is supported by long-term data. Numerical projections show that this amplifying effect causes a major risk of population extinction. In general, such an "evolutionary trap" toward extinction threatens populations in which there is a substantial mating cost for females, and environmental changes or management practices skew the ASR toward males.

Aggression and its Management in Adolescent Forensic Psychiatric Care

The overall goal of this study was to explore and identify good aggression management methods and on that basis to produce recommendations for aggression management in the adolescent forensic setting. The study was conducted in three phases. In Phase I, staff’s (n = 58) perception of adolescent aggressive behaviour and methods to manage it was examined. In Phase II, staff’s (n = 30) perception of treatment settings and treatment interventions available were studied. In Phase III, the effectiveness of an aggression management programme was evaluated. The data were collected during the period 2004-2007. Participants perceived adolescent aggressive behaviour in a similar way and described aggressive behaviour as being a comprehensible phenomenon. Management methods used to control aggressive situations were alike, although the practical solutions varied between the study units, especially regarding coercive methods. Staff members proposed more time and better opportunities to discuss and evaluate the aggression situation in order to improve the methods used. The treatment settings were similar in studied forensic units and interventions were primarily focused on psychological aspects, including management of aggressive behavior. A comprehensive aggression management programme proved to be effective in decreasing incidents of violence. The use of coercive methods in aggression situations decreased and injuries to the staff became less frequent. If staff members intend to apply high quality management methods in aggression situations they have to share a consistent understanding of aggressive behaviour and need to be aware of the various methods available. In addition, they should learn more about assessment methods in order to improve aggression management. International comparison of aggression, methods for managing it and service provision creates a starting point for developing equal care provision and realization within and between European countries.

Aggression and accountability : how caregivers and law enforcers cope

Objectif. L’objectif est de comprendre comment les intervenants en relation d’aide et les agents des forces de l’ordre composent avec la violence au travail et le stress lié à l’imputabilité. Un cadre théorique basé sur l’identité professionnelle est proposé afin de comprendre la modulation de la santé psychologique au travail et testé via le Professional Quality of Life des intervenants en protection de la jeunesse. Les facteurs de prédiction de la banalisation de la violence au travail et des impacts psychologiques de cette banalisation sont également étudiés. Méthodologie. Un sondage mené auprès d’un échantillon représentatif constitué de 301 intervenants en protection de la jeunesse a permis d’examiner le Professional Quality of Life. Les effets de l’exposition à la violence en milieu de travail, à l’exposition au matériel traumatique et du stress lié à l’imputabilité sur la fatigue de compassion ont été analysés à l’aide d’équation structurelle. Les effets indirects attribuables au genre, au soutien organisationnel perçu, à l’adhésion à l’identité professionnelle, aux stratégies d’adaptation et à la confiance en ses moyens pour gérer un client agressif ont été mesurés. Pour l’examen des facteurs de prédiction de la banalisation de la violence au travail, les résultats d’un sondage mené auprès de 1141 intervenants en relation d’aide et des forces de l’ordre ont été analysés à l’aide de régression linéaire. L’analyse des réponses des 376 intervenants de cet échantillon ayant rapporté avoir été perturbé par un acte de violence au travail a permis de mesurer l’impact de la banalisation sur les conséquences psychologiques suite à une victimisation au travail. Les effets indirects attribuables à la banalisation de la violence ont été mesurés. Des analyses différenciées en fonction du sexe ont également été menées. Résultats. L’exposition à la violence, le sentiment d’imputabilité et l’évitement amplifiaient la fatigue de compassion chez les intervenants en protection de la jeunesse sondés. Les attitudes masculines, l’adhésion à l’identité professionnelle, la confiance en ses moyens pour gérer les clients agressifs l’atténuaient. Quant aux facteurs de prédiction de la banalisation de la violence au travail, les participants masculins étaient plus enclins que les femmes à la normaliser. Les agents des forces de l’ordre percevaient davantage la violence comme tabou que les intervenants en relation d’aide. Les facteurs organisationnels avaient tous un effet négatif sur le tabou entourant la violence au travail. Finalement, l’âge, les victimisations antérieures, les blessures graves et percevoir la violence au travail comme un tabou augmentaient le nombre de conséquences psychologiques suite à une victimisation. Les analyses différenciées en fonction du sexe ont identifié des facteurs de prédiction spécifiques aux hommes et aux femmes. Implications. Lors de déploiement de stratégies organisationnelles afin d’aider les employés à gérer avec les stress liés au travail, les organisations doivent considérer l’identité professionnelle de leur travailleur ainsi que des différences en fonction du sexe et du genre.

Chemical communication, aggression, and conspecific recognition in the fish Nile tilapia

The chemical modulation of agonistic behavior and conspecific recognition were tested in juveniles of the fish Nile tilapia, Oreochromis niloticus (L.). After a 7-day isolation period, the fish were grouped (four individuals per aquarium) for 7 days. Then fish of alpha and beta ranks (previously matched for similar size) were paired in a neutral territory for analysis of their agonistic interaction. Pairs composed of alpha and beta fish were established with either fish from the same group (familiar) or from two different groups (unfamiliar). The pairs were tested in contiguous compartments, either with water exchange between the compartments or in the absence of water exchange. In each condition the fish were separated by a transparent glass partition. Twelve pairs were tested in each experimental condition. Fish behavior was videotaped and the following variables were analyzed: (a) frequency of and time spent in agonistic patterns, (b) latency to start fighting, and (c) duration of swimming. Water exchange between compartments decreased agonistic interactions. This effect, however, was more pronounced in pairs of fish coming from the same group (in this case, subordinate fish spent less time in confrontations than dominant ones). We conclude that chemical communication decreases aggression in this species by (1) inducing an alarm reaction and (2) increasing conspecific recognition (thus stabilizing the dominance hierarchy). (C) 1997 Elsevier B.V.

Does sex influence intraspecific aggression and dominance in Nile tilapia juveniles?

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Digit Ratio (2D:4D), Aggression, and Testosterone in Men Exposed to an Aggressive Video Stimulus

The relative lengths of the 2nd and 4th digits (2D:4D) is a negative biomarker for prenatal testosterone, and low 2D:4D may be associated with aggression. However, the evidence for a 2D:4D-aggression association is mixed. Here we test the hypothesis that 2D:4D is robustly linked to aggression in challenge situations in which testosterone is increased. Participants were exposed to an aggressive video and a control video. Aggression was measured after each video and salivary free testosterone levels before and after each video. Compared to the control video, the aggressive video was associated with raised aggression responses and a marginally significant increase in testosterone. Left 2D:4D was negatively correlated with aggression after the aggressive video and the strength of the correlation was higher in those participants who showed the greatest increases in testosterone. Left 2D:4D was also negatively correlated to the difference between aggression scores in the aggressive and control conditions. The control video did not influence testosterone concentrations and there were no associations between 2D:4D and aggression. We conclude that 2D:4D moderates the impact of an aggressive stimulus on aggression, such that an increase in testosterone resulting from a challenge is associated with a negative correlation between 2D:4D and aggression.

Aggression and its function as a hub mediating host defense against the slavemaking ant Protomognathus americanus

In meiner Dissertation beschäftigte ich mich mit unterschiedlichen Verteidungsstrategien, derenrnEffektivität und Evolution, der Ameisenart Temnothorax longispinosus (“Sklaven”), gegenüberrneinem sozialen Parasiten - der nahverwandten, sklavenhaltenden Art Protomognathusrnamericanus (“Sklavenhalter”). Wir entdeckten eine neue Kategorie der Verteidigungsstrategie,rnwelche es dem Wirten ermöglicht, flexibel auf die nicht vorhersagbaren Angriffe des Parasitenrnzu reagieren. Darüber hinaus erforschten wir, wie die Wirte ihre kollektive Verteidigung an einernVielzahl unterschiedlicher Angreifer anpassen können. Wir konnten feststellen, dass Wirte in derrnLage sind ihre kollektive Verteidigung dem Grad der Bedrohung anzupassen. Dies weist daraufrnhin, dass Selektion die Verteidigung gegen unterschiedliche Typen von Angreifern voneinanderrnunabhängig beeinflussen könnte. In einer dritten Studie belegten wir experimentell, dass diernParasiten die Evolution der Kolonieaggressivität der Wirtsart direkt beeinflussen. Die letztenrnbeiden Publikationen beschäftigten sich mit Sklavenrebellion, einer rätselhaftenrnVerteidigungsstrategie, da noch unklar ist, wie eine Eigenschaft von nicht reproduzierendenrnIndividuen vererbt werden kann. In einer Metaanalyse konnten wir die weite Verbreitung undrnhohe Variabilität dieser Eigenschaft dokumentieren, und fanden Hinweise, dassrnVerwandtenselektion eine mögliche Erklärung für die Evolution dieses Merkmals darstellenrnkönnte.

The Impact of Parental Psychological Control on College Students’ Relational Aggression and Friendship Quality

The present study investigated the relationships between parental psychological control and college students’ relational aggression and friendship quality. Based on previous research, it was expected that parents’ use of psychological control would be associated with students’ increased use of relational aggression with peers and lower friendship quality. Students completed a series of survey measures assessing their mothers’ and fathers’ use of psychological control, behavioral control, and warmth/acceptance. Students also completed a series of survey measures assessing their friendship quality, social skills, relational aggression, self-esteem, and social desirability. The study’s findings revealed that parental psychological control was associated with and predicted students’ increased use of relational aggression with peers. Parental psychological control was also associated with students’ lower friendship quality. However, parents’ use of psychological control did not predict students’ friendship quality after accounting for the influence of students’ personal and peer relationship variables. This finding suggests that characteristics of peer relationships may play a larger role than parenting behaviors in shaping college students’ friendships. The study also found that students who displayed higher levels of relational aggression had lower quality friendships. Other findings revealed that the relationship between parental psychological control and students’ friendship quality can be partially explained by students’ use of relational aggression with peers. Students’ friendship quality can also help to explain the influence of parental psychological control on students’ relational aggression. In addition, the study found that combinations of parenting behaviors were more informative predictors of students’ relational aggression and friendship quality than psychological control alone. Finally, this study revealed the importance of assessing participants’ social desirability when measuring sensitive personal qualities such as relational aggression, friendship quality, and self-esteem. Overall, this study contributes to the field of research on parental psychological control by revealing its effects on college students’ relational aggression and friendship quality.

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.

Atypical antipsychotics in the treatment of pathological aggression in children and adolescents: literature review and clinical recommendations

Objective: To review the literature about the use of atypical antipsychotics in the treatment of pathological aggression in children and adolescents. Method: The databases MEDLINE, SciELO, and LILACS were searched for publications in Portuguese or English from 1992 to August 2011 using the following keywords: mental disease, child, adolescent, treatment, atypical antipsychotic, aggressive behavior, aggression, and violent behavior. Results: Sixty-seven studies of good methodological quality and clinical interest and relevance were identified. Studies including children and adolescents were relatively limited, because few atypical antipsychotics have been approved by the Food and Drug Administration (FDA). All the medications included in this review (risperidone, olanzapine, quetiapine, ziprasidone, aripiprazole and clozapine) have some effectiveness in treating aggression in children and adolescents, and choices should be based on clinical indications and side effects. Conclusions: There are few studies about the effectiveness and safety of atypical antipsychotics for the pediatric population, and further randomized controlled studies with larger groups of patients and more diagnostic categories, such as severe conduct disorder and oppositional defiant disorder, should be conducted to confirm the results reported up to date and to evaluate the impact of long-term use.