Validation of the aceto-carmine technique for evaluating phenotypic sex in Nile tilapia (Oreochromis niloticus) fry

In this study a method for evaluating phenotypic sex in Nile tilapia was validated. A technique that uses aceto-carmine squash mounts to stain the entire gonadal tissue for microscopic examination (Method 2- squash mounts) was compared with a technique based on traditional histology. Approximately 2600 Nile tilapia fry weighing and measuring, respectively, between 0.25-2.50g and 26-53mm, aged 35 to 60 days after hatch (DAH), were sexed using this methodology. In situ microscopic examination on the gonads was also performed. A reliable sexing using squash mount was possible with fish weighing more than 0.500g, 45-47 DAH. Results from microscopic observation using the aceto-carmine stain coincided 100% with the histological examination. Male gonadal tissue was characterized by the presence of cysts containing spermatogonia and spermatocytes, while females were easily identified by the presence of oocytes at the perinucleolar stage. The technique proved to be efficient not only in terms of evaluating sex proportion in fish but also because it allows immediate evaluation of gonadal sex and demands less time and labour.

Demographic differences in public attitudes towards sex offenders

Emotionally fueled public responses to news of released sex offenders have the potential to jeopardize the re-entry process, for example, hindering access to stable housing and employment opportunities. Influencing change in public attitudes towards sex offenders so that they are conducive to successful community re-entry is important in efforts to prevent recidivism. Maximizing the effectiveness of attempts to change public attitudes first requires identifying whether specific demographic groups are more prone to negative attitudes, so that attempts to change attitudes can be appropriately targeted. In the present study, 401 community members completed an online questionnaire designed to assess the affective, cognitive and behavioral dimensions of attitudes towards sex offenders. Differences in attitudes towards sex offenders based on respondent sex, age, educational attainment, occupation, parental status and familiarity with victims and perpetrators of sexual assault were investigated. Females demonstrated more-negative attitudes on affective and behavioral measures compared with males, and respondents with low levels of educational attainment demonstrated more-negative attitudes than respondents with higher levels of educational attainment on cognitive and behavioral measures; however, all groups demonstrated negative attitudes towards sex offenders to some extent. Implications for community-level interventions that promote effective re-entry, and hence reduce the likelihood of sexual reoffending are discussed.

The sex factor : media representations of women and men in Australia

Guest edited and with an introduction by Janine Little, this collection of five scholarly articles deals with the Australian media's representation of women in coverage of some of the most controversial issues in contemporary society. The authors are from the disciplines of sociology, journalism and literary studies, with four from Deakin University and one from Flinders University, Adelaide. This enables the monograph to consider a range of phenomena arising from the way that Australia situates women and men as media subjects

Occupational health and safety among commercial sex workers

The concept of occupational health and safety (OHS) for commercial sex workers has rarely been investigated, perhaps because of the often informal nature of the workplace, the associated stigma, and the frequently illegal nature of the activity. We reviewed the literature on health, occupational risks, and safety among commercial sex workers. Cultural and local variations and commonalities were identified. Dimensions of OHS that emerged included legal and policing risks, risks associated with particular business settings such as streets and brothels, violence from clients, mental health risks and protective factors, alcohol and drug use, repetitive strain injuries, sexually transmissible infections, risks associated with particular classes of clients, issues associated with male and transgender commercial sex workers, and issues of risk reduction that in many cases are associated with lack of agency or control, stigma, and legal barriers. We further discuss the impact and potential of OHS interventions for commercial sex workers. The OHS of commercial sex workers covers a range of domains, some potentially modifiable by OHS programs and workplace safety interventions targeted at this population. We argue that commercial sex work should be considered as an occupation overdue for interventions to reduce workplace risks and enhance worker safety.

Little evidence that condition, stress indicators, sex ratio, or homozygosity are related to landscape or habitat attributes in declining woodland birds

Habitat loss, fragmentation and degradation are drivers of major declines in biodiversity and species extinctions. The actual causes of species population declines following habitat change are more difficult to discern and there is typically high covariation among the measures used to infer the causes of decline. The causes of decline may act directly on individual fitness and survival, or through disruption of population processes. We examined the relationships among configuration, extent and status of native vegetation and three commonly used indicators of individual body condition and chronic stress (haemoglobin level, haematocrit, residual body mass condition index) in 13 species of woodland-dependent birds in south-eastern Australia. We also examined two measures of changes to population processes (sex ratio and individual homozygosity) in ten species and alleic richness in five species. We found little support for relationships between site or landscape characteristics and individual or population response variables, notwithstanding that our simulations showed we had sufficient power to detect relatively small effects. We discuss possible causes of the absence of detectable habitat effects in this system and the implications for the usefulness of individual body condition and easily measured haematological indices as indicators of the response of avian populations to habitat change. © 2012 The Authors.

Sex-differences in reasons for non-participation at recruitment : Geelong Osteoporosis Study

Background : Understanding reasons for non-participation in health studies can help guide recruitment strategies and inform researchers about potential sources of bias in their study sample. Whilst there is a paucity of literature regarding this issue, it remains highly plausible that men and women may have varied reasons for declining an invitation to participate in research. We aimed to investigate sex-differences in the reasons for non-participation at baseline of the Geelong Osteoporosis Study (GOS).

Methods : The GOS, a prospective cohort study, randomly recruited men and women aged 20 years and over from a region in south-eastern Australia using Commonwealth electoral rolls (2001–06 and 1993–97, respectively). Reasons for non-participation (n=1,200) were documented during the two recruitment periods. We used the Pearson’s chi squared test to explore differences in the reasons for non-participation between men and women.

Results : Non-participation in the male cohort was greater than in the female cohort (32.9% vs. 22.9%; p<0.001). Overall, there were sex-differences in the reasons provided for non-participation (p<0.001); apparent differences related to time constraints (men 26.3% vs. women 10.4%), frailty/inability to cope with or understand the study (men 18.7% vs. women 30.6%), and reluctance over medical testing (men 1.1% vs women 9.9%). No sex-differences were observed for non-participation related to personal reason/disinterest, and language- or travel-related reasons.

Conclusions : Improving participation rates in epidemiological studies may require different recruitment strategies for men and women in order to address sex-specific concerns about participating in research.

Genetic architecture of sexually selected traits - lessons from guppies

I discuss a number of experiments designed to explore the genetic basis of sexual ornamentation and associated life history traits in guppies. This system is unusual because of the large Y-linked contribution to ornamentation and male fitness, and because the Y-chromosome is implicated in inbreeding depression. I discuss the implications of intralocus sexual conflict for the evolution of sex-linkage in guppies and the potential for such a process to drive the evolutionary erosion of Y-chromosomes.

Distance from water, sex and approach direction influence flight distances among habituated black swans

In many animals, response to predators occurs at greater distances the further an individual is from a refuge, but this has rarely been investigated in birds. Here, we test the hypothesis that the further from refuge (i.e. water) a foraging black swan Cygnus atratus is situated, the longer its flight initiation distance (FID) in response to a pedestrian approach on land. As predicted, swans situated farther from water exhibited longer FIDs compared with those closer to the shore. In addition, there was the possibility of an interesting interaction effect (p < 0.061) of sex and direction of approach on FID. Whilst males tended to not alter their response in relation to the angle of approach relative to the water, females tended to respond at longer distances, when approached from the shore than when approached from the land or parallel to the shore. This is one of the first reports of sex differences in FIDs for birds, with sex differences only manifesting themselves under certain approach types. Group size, the order of repeated approaches, and time of day did not influence responses, although starting distance of approach was positively related to FID.