Causes of male sexual trait divergence in introduced populations of guppies

Males from different populations of the same species often differ in their sexually selected traits. Variation in sexually selected traits can be attributed to sexual selection if phenotypic divergence matches the direction of sexual selection gradients among populations. However, phenotypic divergence of sexually selected traits may also be influenced by other factors, such as natural selection and genetic constraints. Here, we document differences in male sexual traits among six introduced Australian populations of guppies and untangle the forces driving divergence in these sexually selected traits. Using an experimental approach, we found that male size, area of orange coloration, number of sperm per ejaculate and linear sexual selection gradients for male traits differed among populations. Within populations, a large mismatch between the direction of selection and male traits suggests that constraints may be important in preventing male traits from evolving in the direction of selection. Among populations, however, variation in sexual selection explained more than half of the differences in trait variation, suggesting that, despite within-population constraints, sexual selection has contributed to population divergence of male traits. Differences in sexual traits were also associated with predation risk and neutral genetic distance. Our study highlights the importance of sexual selection in trait divergence in introduced populations, despite the presence of constraining factors such as predation risk and evolutionary history.

The short anger measure: development of a measure to assess anger in forensic populations

In this brief report, we describe the development of a brief measure of anger that may be used by nurses and other professionals to assess anger and changes in anger with male offenders. The Short Anger Measure, a 12-item self-report measure of angry feelings and aggressive impulses, was administered to 73 male offenders. The measure showed sound psychometric properties (internal consistency reliability, test–retest reliability) and concurrent validity with an established measure of anger. The potential use of the measure by nurses working in forensic settings is discussed.

Toward a clinically meaningful taxonomy of violent offenders: the role of anger and thinking styles

 This thesis identified a clinically meaningful three-group classification system of violent offenders utilising patterns of anger and crime-supporting beliefs using a sample of 305 male violent prisoners. The three types demonstrated differential outcomes following completion of a violence intervention program, highlighting the need for interventions more tailored toward treatment needs.

Measurement of stable changes of self-management skills after rehabilitation: a latent state-trait analysis of the Health Education Impact Questionnaire (heiQ™)

To assess stable effects of self-management programs, measurement instruments should primarily capture the attributes of interest, for example, the self-management skills of the measured persons. However, measurements of psychological constructs are always influenced by both aspects of the situation (states) and aspects of the person (traits). This study tests whether the Health Education Impact Questionnaire (heiQ™), an instrument assessing a wide range of proximal outcomes of self-management programs, is primarily influenced by person factors instead of situational factors. Furthermore, measurement invariance over time, changes in traits and predictors of change for each heiQ™ scale were examined.

Problem gambling and intimate partner violence : a systematic review and meta-analysis

This study provides a systematic review of the empirical evidence related to the association between problem gambling and intimate partner violence (IPV). We identified 14 available studies in the systematic search (8 for victimisation only, 4 for perpetration only and 2 for both victimisation and perpetration). Although there were some equivocal findings, we found that most of the available research suggests that there is a significant relationship between problem gambling and being a victim of IPV. There was more consistent evidence that there is a significant relationship between problem gambling and perpetration of IPV. Meta-analyses revealed that over one third of problem gamblers report being victims of physical IPV (38.1%) or perpetrators of physical IPV (36.5%) and that the prevalence of problem gambling in IPV perpetrators is 11.3%. Although the exact nature of the relationships between problem gambling and IPV is yet to be determined, the findings suggest that less than full employment and clinical anger problems are implicated in the relationship between problem gambling and IPV victimization and that younger age, less than full employment, clinical anger problems, impulsivity, and alcohol and substance use are implicated in the relationship between problem gambling and IPV perpetration. The findings highlight the need for treatment services to undertake routine screening and assessment of problem gambling, IPV, alcohol and substance use problems, and mental health issues and provide interventions designed to manage this cluster of comorbid conditions. Further research is also required to investigate the relationship between problem gambling and violence that extends into the family beyond intimate partners.

Changes in the platelet intracellular calcium response to serotonin in patients with major depression treated with electroconvulsive therapy: state or trait marker status.

Platelet serotonin type 2A receptor (5-HT2A) sensitivity changes have previously been documented in depression, although it is unclear if this represents a stable trait marker of the illness, or whether it represents an acute state marker of depression that would change with treatment. Electroconvulsive therapy (ECT) may be a useful intervention to separate out trait and state marker status avoiding the potential confounding effects of pharmacotherapy on receptor function. Using spectrofluorometry, the platelet 5HT2A, receptor sensitivity as reflected by the intracellular calcium response to serotonin stimulation, was measured every week in patients suffering from major depression and undergoing ECT. There was a significant drop in the platelet response to serotonin stimulation over a course of ECT, with an associated progressive decrease in Hamilton Rating Scale of Depression (HAM-D) scores. This may suggest either decreased sensitivity of platelet 5HT2A receptors as a mechanism of action of ECT, or changes in second messengers such as the inositide phospholipid system. This suggests that the enhanced sensitivity of platelet 5HT2A receptors may be a state marker of major depression.

The influence of mindfulness meditation on angry emotions and violent behavior on Thai technical college students

Introduction: Violence among technical college students is a significant issue in Thailand, South East Asia, and yet few interventions are available for use with this group. In this study the outcomes of a culturally appropriate intervention, mindfulness meditation (MM), on anger and violent behavior are reported. The MM intervention was delivered over three consecutive weeks to technical college students (n = 40) and the effects compared to a comparison group (n = 56) who attend classes as usual. Methods: Both the intervention and comparison group completed a series of validated self-report measures on aggressive and violent behavior perpetration and victimization on three occasions (pre-intervention, 1 month and 3 month post-intervention). Results: Program participants reported lower levels of anger expression at one month follow-up, but there were no observed group. ×. time interactions for self-reported violent behavior. Rates of victimization changed over time, with one interaction effect observed for reports of being threatened. Conclusions: MM may have the potential to improve emotional self-control, but is likely to only impact on violent behavior when this is anger mediated.

Toward a clinically meaningful taxonomy of violent offenders: the role of anger and thinking styles

Violent offender rehabilitation programs aim to reduce the risk of re-offending in known offenders by addressing a range of different treatments needs, often with core intervention targets of improving anger regulation and altering antisocial beliefs and thinking styles. Such programs have proven efficacy in reducing recidivism for some, but not all, violent offenders, and little is known about the effects of these programs on different offender types. This study investigates whether subtypes of violent offenders can be meaningfully identified and considers how this influences short-term treatment outcomes. Cluster analysis identified three distinctive violent offender groups within a sample of 305 male offenders who had been assessed for participation in a violent offender rehabilitation program. An "unregulated" group had high levels of anger experience and expression and low levels of anger control, and held beliefs that were strongly supportive of a criminal lifestyle. A "regulated" group demonstrated levels of anger and beliefs supporting criminal activity that were not in a range that warranted treatment. Finally, an "overregulated" group was assessed as the group at highest risk of violent re-offending and had low levels of anger experience and expression and an absence of beliefs supporting criminal activity. The unregulated group appeared to gain the most benefit from treatment, although it had the highest levels of criminal thinking and problematic anger. These findings nonetheless offer support for the hypothesis that violent offender treatment programs may be optimally effective when targeted at particular types of offenders.

Longitudinal predictors of domestic violence perpetration and victimization: a systematic review

Domestic violence (DV) is a serious and complex social issue which is associated with significant costs to both those individuals who are directly affected and the wider community. Preventative approaches with vulnerable population groups represent an important component of any integrated response to DV and should be informed by an understanding of those factors that influence violence developmentally. This paper reports the findings of a systematic review of longitudinal studies that have prospectively investigated childhood and/or adolescent predictors of DV perpetration and/or victimization among adult men and women in intimate relationships. We identified 25 original studies that met the inclusion criteria, all of which investigated predictors of domestic physical abuse. Few studies prospectively examined psychological, sexual and verbal abuse. Child and adolescent abuse, family of origin risks, child and adolescent behavioral problems, adolescent peer risks, and sociodemographic risks were all identified as significant predictors of DV perpetration and victimization. It is concluded that early childhood and adolescent factors are consistent predictors in the development of DV perpetration and victimization and that prevention and early intervention approaches targeting these factors are likely to prove the most effective.

The relationship between exposure to violence and anger in Thai adolescents

Youth violence is a serious public health problem in Thailand, and yet is poorly understood and is thought to vary considerably between metropolitan and rural areas. This article reports the findings of a cross-sectional study involving 1,170 technical college students who completed self-report questionnaires assessing the frequency of violent acts, antisocial behavior, and angry emotion. There were no differences in self-reported violent activities between metropolitan and rural participants, but those attending colleges in the metropolitan areas reported more acts involving weapons. Scores on the measure of anger expression predicted physical and verbal assault, specifically punching and name calling, suggesting that the implementation of interventions which help students to improve control over anger may be a useful violence prevention approach.

Variable environmental effects on a multicomponent sexually selected trait

Multicomponent signals are made up of interacting elements that generate a functional signaling unit. The interactions between signal components and their effects on individual fitness are not well understood, and the effect of environment is even less so. It is usually assumed that color patterns appear the same in all light environments and that the effects of each color are additive. Using guppies, Poecilia reticulata, we investigated the effect of water color on the interactions between components of sexually selected male coloration. Through behavioral mate choice trials in four different water colors, we estimated the attractiveness of male color patterns, using multivariate fitness estimates and overall signal contrast. Our results show that females exhibit preferences that favor groups of colors rather than individual colors independently and that each environment favors different color combinations. We found that these effects are consistent with female guppies selecting entire color patterns on the basis of overall visual contrast. This suggests that both individuals and populations inhabiting different light environments will be subject to divergent, multivariate selection. Although the appearance of color patterns changes with light environment, achromatic components change little, suggesting that these could function in species recognition or other aspects of communication that must work across environments. Consequently, we predict different phylogenetic patterns between chromatic and achromatic signals within the same clades.