Urbanisation factors impacting on ant (Hymenoptera: Formicidae) biodiversity in the Perth metropolitan area, Western Australia: Two case studies

Two synchronous projects undertaken in 2011 examined the likely impact of increasing urban densification on invertebrate populations within urban settlement in Perth, Western Australia. One project analysed the ant fauna found in 20 gardens and lawns in small to very small properties (these having a bungalow or duplex (semi-detached) as the main residential building, and a lawn or garden area of 43 m²–332 m²) east, south, north and west of the Central Business District (CBD). The other project examined the ant fauna at 14 sites, principally in native regrowth along the Kwinana Freeway, a major artery that runs north to south through Perth’s suburbs. The gardens and lawns produced a very depauperate fauna of 26 ant species, of which a maximum of 20 were native and at least six species were exotic. The ant fauna from regrowth adjacent to the Kwinana Freeway and at two additional sites (one a bush control) was more than twice as rich, the 56 species collected including only two exotics. In the garden project, ant richness, evenness and abundance were not significantly correlated with size of the garden area. The same applied even when the exotic Pheidole megacephala-dominated gardens were removed from the analysis. Ordination analysis combining the two sets of data revealed a distinct clustering of most of the regrowth sites, whereas the bush control stood alone and garden or lawn sites exhibited a much looser pattern of association. We suggest that increasing the density of Perth suburbs is resulting in drastic loss of native invertebrate fauna, of which ants are a useful bioindicator. However, native vegetation regrowth along major arterial roads could act as a reservoir for invertebrate species that might otherwise disappear entirely from the Perth metropolitan area.     

Using experiential knowledge to understand urban rat ecology: A survey of Canadian pest control professionals

Rats (Rattus rattus and Rattus norvegicus) are among the most prolific and widespread urban pest species in the world. However, there is relatively little contemporary data regarding the ecology of rats in urban centers, preventing the development of effective strategies for urban rat management. Practical constraints associated with field studies suggest the need for more efficient methods of data collection, one of which could involve pest control professionals, who have considerable experiential knowledge of urban rats. The objective of this study was to gather data regarding urban rat ecology through a survey of Canadian pest control professionals and to determine whether such a survey could be useful for the collection of ecological data regarding pest species. Survey results suggested that rat infestations fluctuate seasonally and that there are a variety of environmental factors that may attract rats, particularly exposed garbage, abandoned buildings, and compost. Respondents suggested that rat infestations are most frequent and/or severe in residential areas, commercial areas dealing with food, as well as in neighborhoods of low socioeconomic status. The majority of respondents believed that rats pose at least a moderate health risk to the general public and to themselves, and they also believed that although poison baiting is the cheapest and easiest method of rat control, environmental modification is the most effective way to control rat infestations in the long term. Despite issues with low response rates, these results suggest that pest control professionals may be a valuable source of data regarding urban pest species.     

Do ENDAs End Discrimination for Behaviorally Gay Men?

Twenty-two states have implemented state Employment Nondiscrimination Acts (ENDAs) making sexual orientation discrimination illegal, and Congress has repeatedly considered a federal ENDA. However, we know very little about the impact of existing ENDAs and the likely impact of future ENDAs. I describe the implementation of ENDAs and highlight their shortcomings relative to federal employment nondiscrimination law. Despite their shortcomings, I show that state ENDAs decrease wage differentials by roughly 20 % for behaviorally gay men. ENDAs appear to reduce this wage differential by reducing the portion of wage differentials typically associated with discrimination. These results inform a contemporary policy debate over the necessity and impact of expanded protection from discrimination for gay men. (JEL J1, J3, J7)     

An examination of the relationship between child sexual offending and psychopathy

The participants in this study were adult males (N = 111) who were accused of various sexual crimes against children 16 years of age or younger, and who were evaluated at a state forensic facility in a large Midwestern state. This study examined the relationship of Psychopathy Checklist-Revised (PCL-R) scores to type of child sexual offender (same sex extrafamilial, opposite sex extrafamilial, and incest offenders), the presence of violence during the most recent child sexual offense, and criminal versatility. Results indicated that those sexual offenders who employed physical violence against the children they abused were significantly more psychopathic than those who did not. No significant differences were found between types of child sexual offenders or with general criminal versatility.     

The effects of physical activity and sedentary behavior on cognitive health in older adults

Physical activity has been shown to be positively associated with cognitive health, but the mechanisms underlying the benefits of physical activity on cognitive health are unclear. The present study simultaneously examined two hypotheses using structural equation modeling (SEM). The depression-reduction hypothesis states that depression suppresses cognitive ability and that physical activity alleviates dysphoric mood and thereby improves cognitive ability. The social-stimulation hypothesis posits that social contact, which is often facilitated by socially laden physical activities, improves cognitive functioning by stimulating the nervous system. Sedentary behavior in the absence of physical activity is expected to exert an inverse relationship on cognitive health through each of these hypotheses. Community-dwelling elders (N = 158) were administered a variety of measures of cognition, depression, social support, and physical activity. SEM techniques provided partial support for the social-stimulation hypothesis and depression-reduction hypothesis. Implications for treating depression and improving cognitive functioning are discussed.     

Anabolic responses to resistance training in older men and women: a brief review

Resistance training has been shown to be the most effective exercise mode to induce anabolic adaptations in older men and women. Advances in imaging techniques and histochemistry have increased the ability to detect such changes, confirming the high level of adaptability that remains in aging skeletal muscle. This brief review presents a summary of the resistance-training studies that directly compare chronic anabolic responses to training in older (>60 years) men and women. Sixteen studies are summarized, most of which indicate similar relative anabolic responses between older men and women after resistance training. Relatively small sample sizes in most of the interventions limited their ability to detect significant sex differences and should be considered when interpreting these studies. Future research should incorporate larger sample sizes with multiple measurement time points for anabolic responses.     

The interaction of aging and 10 years of racing on ultraendurance running performance

The aim of this study was to examine the interaction between aging and 10 years of racing in endurance runners. Race-time data from 194 runners who had completed 10 consecutive 56-km ultramarathons were obtained. The runners were either 20.5 +/- 0.7, 30.0 +/- 1.0, 39.9 +/- 0.9, or 49.4 +/- 1.0 years old at their first race. Each runner's race speed was determined for each race over the 10 years. Data were analyzed using repeated-measures ANOVA, one-way ANOVA, and independent t tests and showed that performance improved and declined at greater rates for younger runners; younger runners had a greater capacity for improvement than older runners; approximately 4 years were required to reach peak racing speed, regardless of age; it was not possible to compete at peak speed for more than a few years; and the combined effects of 10 years of aging and racing neither improve nor worsen net performance. In conclusion, these data suggest that although these runners showed similar patterns of change in race speed over a 10-year period, the extent of change in performance was greater in younger than in older runners.     

Differences in childhood sexual abuse experience between adult Hispanic and Anglo women in a primary care setting

The literature on racial and ethnic factors in childhood sexual abuse is limited. The purpose of this exploratory study was to document Hispanic-Anglo differences in childhood sexual abuse experiences and assess whether these differences may be explained by socio-demographic and family environmental differences. Adult Hispanic (n = 69) and Anglo (n = 19) women from a family medicine clinic waiting room reporting a history of childhood sexual abuse completed an in-depth survey concerning the sexual abuse experience and their childhood environment. In this study, Hispanics were more likely to report a family member as the perpetrator and to experience more self-blame as a result of the abuse. Hispanics were also more likely to take action in response to the abuse, especially those who were more acculturated to U.S. culture. However, most of the observed differences in this study could be explained by socio-demographic or family environment variables, not by ethnic background. Qualitative research on the family environments of Hispanic victims of child sexual abuse may further explicate the dynamics and risk factors for abuse by family members.