261 resultados para Female


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 The implications of climate change for global biodiversity may be profound with those species with little capacity for adaptation being thought to be particularly vulnerable to warming. A classic case of groups for concern are those animals exhibiting temperature-dependent sex-determination (TSD), such as sea turtles, where climate warming may produce single sex populations and hence extinction. We show that, globally, female biased hatchling sex ratios dominate sea turtle populations (exceeding 3:1 in >50% records), which, at-a-glance, reiterates concerns for extinction. However, we also demonstrate that more frequent breeding by males, empirically shown by satellite tracking 23 individuals and supported by a generalized bio-energetic life history model, generates more balanced operational sex ratios (OSRs). Hence, concerns of increasingly skewed hatchling sex ratios and reduced population viability are less acute than previously thought for sea turtles. In fact, in some scenarios skewed hatchling sex ratios in groups with TSD may be adaptive to ensure optimum OSRs.

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FRAX(©) evaluates 10-year fracture probabilities and can be calculated with and without bone mineral density (BMD). Low socioeconomic status (SES) may affect BMD, and is associated with increased fracture risk. Clinical risk factors differ by SES; however, it is unknown whether aninteraction exists between SES and FRAX determined with and without the BMD. From the Geelong Osteoporosis Study, we drew 819 females aged ≥50 years. Clinical data were collected during 1993-1997. SES was determined by cross-referencing residential addresses with Australian Bureau of Statistics census data and categorized in quintiles. BMD was measured by dual energy X-ray absorptiometry at the same time as other clinical data were collected. Ten-year fracture probabilities were calculated using FRAX (Australia). Using multivariable regression analyses, we examined whether interactions existed between SES and 10-year probability for hip and any major osteoporotic fracture (MOF) defined by use of FRAX with and without BMD. We observed a trend for a SES * FRAX(no-BMD) interaction term for 10-year hip fracture probability (p = 0.09); however, not for MOF (p = 0.42). In women without prior fracture (n = 518), we observed a significant SES * FRAX(no-BMD) interaction term for hip fracture (p = 0.03) and MOF (p = 0.04). SES does not appear to have an interaction with 10-year fracture probabilities determined by FRAX with and without BMD in women with previous fracture; however, it does appear to exist for those without previous fracture.

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The mud crab, Scylla olivacea, is one of the most economically valuable marine species in Southeast Asian countries. However, commercial cultivation is disadvantaged by reduced reproductive capacity in captivity. Therefore, an understanding of the general and detailed anatomy of central nervous system (CNS) is required before investigating the distribution and functions of neurotransmitters, neurohormones, and other biomolecules, involved with reproduction. We found that the anatomical structure of the brain is similar to other crabs. However, the ventral nerve cord (VNC) is unlike other caridian and dendrobrachiate decapods, as the subesophageal (SEG), thoracic and abdominal ganglia are fused, due to the reduction of abdominal segments and the tail. Neurons in clusters within the CNS varied in sizes, and we found that there were five distinct size classes (i.e., very small globuli, small, medium, large, and giant). Clusters in the brain and SEG contained mainly very small globuli and small-sized neurons, whereas, the VNC contained small-, medium-, large-, and giant-sized neurons. We postulate that the different sized neurons are involved in different functions. Microsc. Res. Tech. 77:189–200, 2014. © 2013 Wiley Periodicals, Inc.

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To gain insight into female-to-male HIV sexual transmission and how male circumcision protects against this mode of transmission, we visualized HIV-1 interactions with foreskin and penile tissues in ex vivo tissue culture and in vivo rhesus macaque models utilizing epifluorescent microscopy. 12 foreskin and 14 cadaveric penile specimens were cultured with R5-tropic photoactivatable (PA)-GFP HIV-1 for 4 or 24 hours. Tissue cryosections were immunofluorescently imaged for epithelial and immune cell markers. Images were analyzed for total virions, proportion of penetrators, depth of virion penetration, as well as immune cell counts and depths in the tissue. We visualized individual PA virions breaching penile epithelial surfaces in the explant and macaque model. Using kernel density estimated probabilities of localizing a virion or immune cell at certain tissue depths revealed that interactions between virions and cells were more likely to occur in the inner foreskin or glans penis (from local or cadaveric donors, respectively). Using statistical models to account for repeated measures and zero-inflated datasets, we found no difference in total virions visualized at 4 hours between inner and outer foreskins from local donors. At 24 hours, there were more virions in inner as compared to outer foreskin (0.0495 +/- 0.0154 and 0.0171 +/- 0.0038 virions/image, p = 0.001). In the cadaveric specimens, we observed more virions in inner foreskin (0.0507 +/- 0.0079 virions/image) than glans tissue (0.0167 +/- 0.0033 virions/image, p<0.001), but a greater proportion was seen penetrating uncircumcised glans tissue (0.0458 +/- 0.0188 vs. 0.0151 +/- 0.0100 virions/image, p = 0.099) and to significantly greater mean depths (29.162 +/- 3.908 vs. 12.466 +/- 2.985 μm). Our in vivo macaque model confirmed that virions can breach penile squamous epithelia in a living model. In summary, these results suggest that the inner foreskin and glans epithelia may be important sites for HIV transmission in uncircumcised men.

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Worldwide, HIV-1 infects millions of people annually, the majority of whom are women. To establish infection in the female reproductive tract (FRT), HIV-1 in male ejaculate must overcome numerous innate and adaptive immune factors, traverse the genital epithelium, and establish infection in underlying CD4(+) target cells. How the virus achieves this remains poorly defined. By utilizing a new technique, we define how HIV-1 interacts with different tissues of the FRT using human cervical explants and in vivo exposure in the rhesus macaque vaginal transmission model. Despite previous claims of the squamous epithelium being an efficient barrier to virus entry, we reveal that HIV-1 can penetrate both intact columnar and squamous epithelial barriers to depths where the virus can encounter potential target cells. In the squamous epithelium, we identify virus entry occurring through diffusive percolation, penetrating areas where cell junctions are absent. In the columnar epithelium, we illustrate that virus does not transverse barriers as well as previously thought due to mucus impediment. We also show a statistically significant correlation between the viral load of inocula and the ability of HIV-1 to pervade the squamous barrier. Overall, our results suggest a diffusive percolation mechanism for the initial events of HIV-1 entry. With these data, we also mathematically extrapolate the number of HIV-1 particles that penetrate the mucosa per coital act, providing a biological description of the mechanism for HIV-1 transmission during the acute and chronic stages of infection.

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Objective: The aim of this study was to examine associations between family-based stressors and depressive symptoms in adolescents.

Method: Participants were 10-14 year olds who participated in a large Australian population study (n=6,552). Depressive symptoms and pubertal development were assessed using the self-report Short Mood and Feelings Questionnaire and the Pubertal Development Scale. Three indicators of stress exposure were examined-low emotional closeness to parents, residential and school transitions, and family conflict. The effect of gender, stress exposure and the interaction of gender and stress exposure on depressive symptoms was tested using multivariate logistic regression.

Results:
High family conflict, residential instability and low emotional closeness with parents were independently associated with adolescent depressive symptoms. There was a significant gender by emotional closeness interaction; females reporting low emotional closeness to their parents were 2.3 times more likely to report high depressive symptoms than females reporting high emotional connections with parents.

Conclusions:
Female adolescents may be more susceptible to particular types of stresses and particularly the quality of the parent-child relationship.

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Intersectional accounts of how women sports fans from diverse cultural backgrounds are represented remain largely unconsidered in fandom literature. This article examines an Australian advertisement for the 2015 Cricket World Cup, which features as its main protagonists female cricket fans supporting a variety of countries. It makes use of a transnational feminist cultural studies paradigm to frame a discussion of how commercial sports media narratives situate these fans as ‘‘ordinary.’’ In considering how the multicultural female sports fan is configured as ordinary in the Australian sporting context, I demonstrate the ways In which narratives of gender and nation are mobilized to situate multicultural women as marginal to both the Australian nation and cricket, despite the prominence given to ethnically diverse women in the advertisement. This manoeuvre, I argue, responds to the cultural and economic transformations of cricket globally, simultaneously denying and universalizing difference as a mechanism to assuage the anxieties generated by the decentering of Western power in international cricket.

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Phenotypic variation and individual experience can create behavioural and/or dietary variation within a population. This may reduce intra-specific competition, creating a buffer to environmental change. This study examined how intrinsic variation affects foraging behaviour of Australian fur seals. Foraging movements of 29 female Australian fur seals were recorded using FastLoc GPS and dive behaviour recorders. For each individual, body mass, flipper length and axis length were recorded, a tooth was sampled to determine age, and milk was collected for diet analysis. Clustering of fatty acid dietary analysis revealed 5 distinct groups in the population. Behaviour was described using 19 indices, which were then reduced to 7 principal components (>80% of the behavioural variation). Bayesian mixed effect models were developed to describe the relationship between these components and intrinsic variation. No association was found between diet and age or body shape; however, age had a negative relationship with component 1 (27% of variation). Older females spent less time at-sea and foraged nearer to the colony. Age had an effect on component 5 (7% of variation), which represented haul-outs and dive depth; older females made fewer visits to haul-out sites and dived deeper to the benthos. This suggests that as animals age they are able to utilise prior knowledge to exploit nearby foraging sites that younger animals are either unaware of, or have yet to gain the experience required to efficiently utilise. Mass had a negative effect on components representing the directedness of a foraging trip, suggesting heavier individuals were more likely to travel directly to a foraging site.

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Within a heterogeneous environment, animals must efficiently locate and utilise foraging patches. One way animals can achieve this is by increasing residency times in areas where foraging success is highest (area-restricted search). For air-breathing diving predators, increased patch residency times can be achieved by altering both surface movements and diving patterns. The current study aimed to spatially identify the areas where female Australian fur seals allocated the most foraging effort, while simultaneously determining the behavioural changes that occur when they increase their foraging intensity. To achieve this, foraging behaviour was successfully recorded with a FastLoc GPS logger and dive behaviour recorder from 29 individual females provisioning pups. Females travelled an average of 118 ± 50 km from their colony during foraging trips that lasted 7.3 ± 3.4 days. Comparison of two methods for calculating foraging intensity (first-passage time and first-passage time modified to include diving behaviour) determined that, due to extended surface intervals where individuals did not travel, inclusion of diving behaviour into foraging analyses was important for this species. Foraging intensity 'hot spots' were found to exist in a mosaic of patches within the Bass Basin, primarily to the south-west of the colony. However, the composition of benthic habitat being targeted remains unclear. When increasing their foraging intensity, individuals tended to perform dives around 148 s or greater, with descent/ascent rates of approximately 1.9 m•s-1 or greater and reduced postdive durations. This suggests individuals were maximising their time within the benthic foraging zone. Furthermore, individuals increased tortuosity and decreased travel speeds while at the surface to maximise their time within a foraging location. These results suggest Australian fur seals will modify both surface movements and diving behaviour to maximise their time within a foraging patch.

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Female genital mutilation (FGM) is widely practised in several regions of the world. It is often associated with physical, psychological, sexual and social sequelae. Migration of persons from cultures that actively practice FGM to the UK and other Western countries increases the chances that clinicians will be faced with patients who have undergone this procedure. Clinical presentations often occur against a background of differences in culture and social identity, which may pose a challenge to any form of intervention. Perceptions of normalcy, human rights violation and gender roles may also differ. This paper discusses historical, cultural, gender and identity issues associated with FGM and its psychological and sexual implications.

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While the issue of boys’ dominance of the curriculum has a long history, the article examines this phenomenon in a contemporary context, through an empirical study with female teachers designing English curriculum around girls’ media in a coeducational secondary school in Victoria, Australia. In this space, teachers, and the researcher, produce and perform both individual gendered identities and plans for the identities of future student subjects, while negotiating subject positions made available to girls and women in broader social contexts. In this instance, negotiations that take place during the development of a unit of work on Mattel's Barbie website form the basis of feminist discourse analysis, enabling us to ‘take stock’ in thinking about what curriculum design is, about where the past is situated in relation to the present, and to question why, within a discursive feminist/postfeminist entanglement, the heritage of feminist intellectual thought in this area seems absent.