28 resultados para sex difference


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The thesis reviews the literature relating to girls and computing within a framework which is structured around three specific questions. First, are there differences between girls and boys in their participation in class computing activities and/or in non-class computing activities? Second, do these differences in participation in computing activities have broader implications which justify the growing concern about the under-representation of girls? Third, wahy are girls under-represented in these activities? Although the available literature is predominantly descriptive, the underlying implicit theoretical model is essentially a social learning model. Girl's differential participation is attributed to learned attitudes towards computing rathan to differences between girls and boys in general ability. These attitudes, which stress the masculine, mathematical, technological aspects of computing are developed through modelling, direct experience, intrinsic and extrinsic reinforcement and generalisation from pre-existing, attitudes to related curriculum areas. In the literature it is implicitly assumed that these attitudes underlie girl's decisions to self-select out of computing activities. In this thesis predictions from a social learning model are complemented by predictions derived from expectancy-value, cognitive dissonance and self-perception theories. These are tested in three separate studies. Study one provides data from a pretest-posttest study of 24 children in a year four class learning BASIC. It examines pre- and posttest differences between girls and boys in computing experience, knowledge and achievement as well as the factors relating to computing achievement. Study two uses a pretest-posttest control group design to study the gender differences in the impact of the introduction of Logo into years 1, 3, 5 and 7 in both a coeducational and single-sex setting using a sample of 222 children from three schools. Study three utilises a larger sample of 1176 students, drawn from three secondary schools and five primary schools, enabling an evaluation of gender differences in relation to a wide range of class computing experiences and in a broader range of school contexts. The overall results are consistent across the three studies, supporting the contention that social factors, rather than ability differences influence girls' participation and achievement in computing. The more global theoretical framework, drawing on social learning, expectancy-value, cognitive dissonance and self-perception theories, provides a more adequate explanation of gender differences in participation than does any one of these models.

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The internet has met with mixed community reactions, especially when the focus is on young people's internet use. There are those who fear that the internet will introduce undesirable people and information into the home, leaving the young vulnerable and exploited. Alternatively, there are others who argue that the exclusion of young people from the internet is one of many examples of the diminishing public space that is made available to young people in this post-modern world. In this article we focus on the internet use of one ‘space deprived’ group of marginalized young people, those who are same-sex attracted. Regardless of some important changes in Australian culture and law, these young people's opportunities to openly live their sexual difference remain restricted. In this article we are interested in exploring the role of the internet as a space in which some important sexuality work can be done. What we found was that the internet was providing young people with the space to practise six different aspects of their sexual lives namely identity, friendship, coming out, intimate relationships, sex and community.

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Women exhibit an enhanced capability for lipid metabolism during endurance exercise compared with men. The underlying regulatory mechanisms behind this sex-related difference are not well understood but may comprise signaling through a myocyte enhancer factor 2 (MEF2) regulatory pathway. The primary purpose of this study, therefore, was to investigate the protein signaling of MEF2 regulatory pathway components at rest and during 90 min of bicycling exercise at 60% VO2peak in healthy, moderately trained men (n = 8) and women (n = 9) to elucidate the potential role of these proteins in substrate utilization during exercise. A secondary purpose was to screen for mRNA expression of MEF2 isoforms and myogenic regulatory factor (MRF) family members of transcription factors at rest and during exercise. Muscle biopsies were obtained before and immediately after exercise. Nuclear AMP-activated protein kinase-{alpha} ({alpha}AMPK) Thr172 (P < 0.001), histone deacetylase 5 (HDAC5) Ser498 (P < 0.001), and MEF2 Thr (P < 0.01) phosphorylation increased with exercise. No significant sex differences were observed at rest or during exercise. At rest, no significant sex differences were observed in mRNA expression of the measured transcription factors. mRNA for transcription factors MyoD, myogenin, MRF4, MEF2A, MEF2C, MEF2D, and peroxisome proliferator-activated receptor-{gamma} coactivator 1{alpha} (PGC1{alpha}) were significantly upregulated by exercise. Of these, MEF2A mRNA increased 25% specifically in women (P < 0.05), whereas MEF2D mRNA tended to increase in men (P = 0.11). Although minor sex differences in mRNA expression were observed, the main finding of the present study was the implication of a joint signaling action of AMPK, HDAC5, and PGC1{alpha} on MEF2 in the immediate regulatory response to endurance exercise. This signaling response was independent of sex.

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The aim of the present study was to examine quantitative differences in lobar cerebral cortical volumes in a healthy adult population. Quantitative volumetric MRI of whole brain, cerebral and cerebellar volumes was performed in a cross-sectional analysis of 97 normal volunteers, with segmented frontal, temporal, parietal and occipital cortical volumes measured in a subgroup of 60 subjects, 30 male and 30 female, matched for age and sex. The right cerebral hemisphere was larger than the left across the study group with a small (<1%) but significant difference in symmetry (P < 0.001). No difference was found between volumes of right and left cerebellar hemispheres. Rightward cerebral cortical asymmetry (right larger than left) was found to be significant across all lobes except parietal. Males had greater cerebral, cerebellar and cerebral cortical lobar volumes than females. Larger male cerebral cortical volumes were seen in all lobes except for left parietal. Females had greater left parietal to left cerebral hemisphere and smaller left temporal to left cerebral hemisphere ratios. There was a mild reduction in cerebral volumes with age, more marked in males. This study confirms and augments past work indicating underlying structural asymmetries in the human brain, and provides further evidence that brain structures in humans are differentially sensitive to the effects of both age and sex.

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Theory predicts skewed offspring sex-ratios in a range of situations in which the economics of producing the two sexes differ. Offspring sex-ratio skews in birds are relatively scarcely observed compared to other taxa. This could be because avian molecular sexing techniques, which allow young birds to be sexed, have only recently become available. Alternatively, birds may be largely constrained from adaptively manipulating the sex-ratio of their offspring. We used a recently-developed molecular sexing technique for birds to sex 420 Yellowhammer Emberiza citrinella offspring from 168 clutches found in Oxfordshire. Clutch sex-ratio of the population did not depart from the expected binomial distribution, and there was no variation in clutch sex-ratio with laying date, breeding attempt, or a variety of habitat variables which were predicted to differentially affect the survival and future reproductive success of offspring of the two sexes. There was no difference in size or growth rate of the sexes and nestling mortality was not sex-biased. Hence, although we can identify possible advantages of manipulating the sex-ratio in this species, it seems not to be used as a breeding strategy. Given the lack of consistent evidence for skewed avian offspring sex-ratios, more experimental work is required to determine whether, and how, birds may adaptively manipulate their offspring sex-ratio.

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By using both mitochondrial and nuclear multiloci markers, we explored population genetic structure, gene flow and sex-specific dispersal of frillneck lizards (Chlamydosaurus kingii) sampled at three locations, separated by 10 to 50 km, in a homogenous savannah woodland in tropical Australia. Apart from a recombinant lizard, the mitochondrial analyses revealed two nonoverlapping haplotypes/populations, while the nuclear markers showed that the frillneck lizards represented three separate clusters/populations. Due to the small population size of the mtDNA, fixation may occur via founder effects and/or drift. We therefore suggest that either of these two processes, or a combination of the two, are the most likely causes of the discordant results obtained from the mitochondrial and the nuclear markers. In contrast to the nonoverlapping mitochondrial haplotypes, in 12 out of 74 lizards, mixed nuclear genotypes were observed, hence revealing a limited nuclear gene flow. Although gene flow should ultimately result in a blending of the populations, we propose that the distinct nuclear population structure is maintained by frequent fires resulting in local bottlenecks, and concomitant spatial separation of the frillneck lizard populations. Limited mark-recapture data and the difference in distribution of the mitochondrial and nuclear markers suggest that the mixed nuclear genotypes were caused by juvenile male-biased dispersal.

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The aim of this work was to evaluate sex differences in the incidence of multiple sclerosis relapses; assess the relationship between sex and primary progressive disease course; and compare effects of age and disease duration on relapse incidence. Annualized relapse rates were calculated using the MSBase registry. Patients with incomplete data or <1 year of follow-up were excluded. Patients with primary progressive multiple sclerosis were only included in the sex ratio analysis. Relapse incidences over 40 years of multiple sclerosis or 70 years of age were compared between females and males with Andersen-Gill and Tweedie models. Female-to-male ratios stratified by annual relapse count were evaluated across disease duration and patient age and compared between relapse-onset and primary progressive multiple sclerosis. The study cohort consisted of 11 570 eligible patients with relapse-onset and 881 patients with primary progressive multiple sclerosis. Among the relapse-onset patients (82 552 patient-years), 48 362 relapses were recorded. Relapse frequency was 17.7% higher in females compared with males. Within the initial 5 years, the female-to-male ratio increased from 2.3:1 to 3.3:1 in patients with 0 versus ≥4 relapses per year, respectively. The magnitude of this sex effect increased at longer disease duration and older age (P < 10−12). However, the female-to-male ratio in patients with relapse-onset multiple sclerosis and zero relapses in any given year was double that of the patients with primary progressive multiple sclerosis. Patient age was a more important determinant of decline in relapse incidence than disease duration (P < 10−12). Females are predisposed to higher relapse activity than males. However, this difference does not explain the markedly lower female-to-male sex ratio in primary progressive multiple sclerosis. Decline in relapse activity over time is more closely related to patient age than disease duration.

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The effects of krill oil as an alternative source of n-3 long-chain PUFA have been investigated recently. There are conflicting results from the few available studies comparing fish oil and krill oil. The aim of this study was to compare the bioavailability and metabolic fate (absorption, β-oxidation and tissue deposition) of n-3 fatty acids originating from krill oil (phospholipid-rich) or fish oil (TAG-rich) in rats of both sexes using the whole-body fatty acid balance method. Sprague-Dawley rats (thirty-six male, thirty-six female) were randomly assigned to be fed either a krill oil diet (EPA+DHA+DPA=1·38 mg/g of diet) or a fish oil diet (EPA+DHA+DPA=1·61 mg/g of diet) to constant ration for 6 weeks. The faeces, whole body and individual tissues were analysed for fatty acid content. Absorption of fatty acids was significantly greater in female rats and was only minimally affected by the oil type. It was estimated that most of EPA (>90 %) and more than half of DHA (>60 %) were β-oxidised in both diet groups. Most of the DPA was β-oxidised (57 and 67 % for female and male rats, respectively) in the fish oil group; however, for the krill oil group, the majority of DPA was deposited (82-83 %). There was a significantly greater deposition of DPA and DHA in rats fed krill oil compared with those fed fish oil, not due to a difference in bioavailability (absorption) but rather due to a difference in metabolic fate (anabolism v. catabolism).

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In his Spleen de Paris or Petits poèmes en prose [Little Prose Poems] Baudelaire (1869) forges an instrument of supple and radical potential, declaring the prose poem a ‘dangerous’ hybrid, which he wills elastic enough and staccato enough, to register the flows, jolts and distractions for the flâneur in the increasingly industrialised Paris. Here,by the mid-19th century, plate glass and gas lighting enable conspicuous consumption. Itis most strikingly the romantic-erotic and the relation between poet and his delicious, execrable wife, his inescapable, pitiless Muse (Baudelaire 1989: 177] that provides the nexus for radical questioning of the whole socio-political economy. Departing from Johnson’s Défigurations (1979) and using Irigaray’s (1984) hypothesis that the economy of sexual difference is the founding trope for the discursive and thus political economy of differences – of culture, ethnicity and class – this article first looks at theway Baudelaire activates the heterosexual relation as a site for social critique. It examines how Perec continues Baudelaire’s prose poetry experiment, offering, pre-May 1968, a revolutionary critique of desire by exploiting formal constraints to deconstruct still further the consumer subject of capitalism. It then investigates Brossard’s ‘hologrammatic’ challenge (1991) to patriarchal regimes of representation and the forms of desire they outlaw. Finally, it suggests how new work by Walwicz (2015)develops and displaces this radical inheritance.

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© 2015 Australian Association of Family Therapy. Increasing numbers of lesbian, gay and bisexual (LGB) adults are entering into parenthood. Previous studies indicate many of these parents receive little or no support from their families of origin due to family members' negative attitudes toward homosexuality. This study looks at the extent to which LGB parents report a lower sense of connectedness to family of origin and friendship networks than heterosexual parents and whether this has an impact on psychological wellbeing in either of these groups. Data were derived from two studies of parents: Work, Love, Play, a study of Australian and New Zealand LGB parents (n=324); and the Longitudinal Study of Australian Children, a population-based study of young children and parents (n=6460). Structural equation modelling was used to explore the relationships between: parent sexuality and family/friendship connectedness, family/friendship connectedness and psychological wellbeing, parent sexuality and psychological wellbeing. LGB parents reported feeling less connected to their families of origin but more connected to their friendship groups than heterosexual parents. Counter to previous studies, we found no difference in the psychological wellbeing of LGB parents compared to heterosexual parents when examining the direct effect of sexuality on psychological wellbeing. Clinical implications for counsellors and family therapists are discussed.

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Background: Up-to-date evidence on levels and trends for age-sex-specific all-cause and cause-specific mortality is essential for the formation of global, regional, and national health policies. In the Global Burden of Disease Study 2013 (GBD 2013) we estimated yearly deaths for 188 countries between 1990, and 2013. We used the results to assess whether there is epidemiological convergence across countries. Methods We estimated age-sex-specific all-cause mortality using the GBD 2010 methods with some refinements to improve accuracy applied to an updated database of vital registration, survey, and census data. We generally estimated cause of death as in the GBD 2010. Key improvements included the addition of more recent vital registration data for 72 countries, an updated verbal autopsy literature review, two new and detailed data systems for China, and more detail for Mexico, UK, Turkey, and Russia. We improved statistical models for garbage code redistribution. We used six different modelling strategies across the 240 causes; cause of death ensemble modelling (CODEm) was the dominant strategy for causes with sufficient information. Trends for Alzheimer's disease and other dementias were informed by meta-regression of prevalence studies. For pathogen-specific causes of diarrhoea and lower respiratory infections we used a counterfactual approach. We computed two measures of convergence (inequality) across countries: the average relative difference across all pairs of countries (Gini coefficient) and the average absolute difference across countries. To summarise broad findings, we used multiple decrement life-tables to decompose probabilities of death from birth to exact age 15 years, from exact age 15 years to exact age 50 years, and from exact age 50 years to exact age 75 years, and life expectancy at birth into major causes. For all quantities reported, we computed 95% uncertainty intervals (UIs). We constrained cause-specific fractions within each age-sex-country-year group to sum to all-cause mortality based on draws from the uncertainty distributions. Findings Global life expectancy for both sexes increased from 65·3 years (UI 65·0-65·6) in 1990, to 71·5 years (UI 71·0-71·9) in 2013, while the number of deaths increased from 47·5 million (UI 46·8-48·2) to 54·9 million (UI 53·6-56·3) over the same interval. Global progress masked variation by age and sex: for children, average absolute differences between countries decreased but relative differences increased.For women aged 25-39 years and older than 75 years and for men aged 20-49 years and 65 years and older, both absolute and relative differences increased. Decomposition of global and regional life expectancy showed the prominent role of reductions in age-standardised death rates for cardiovascular diseases and cancers in high-income regions, and reductions in child deaths from diarrhoea, lower respiratory infections, and neonatal causes in low-income regions. HIV/AIDS reduced life expectancy in southern sub-Saharan Africa. For most communicable causes of death both numbers of deaths and age-standardised death rates fell whereas for most non-communicable causes, demographic shifts have increased numbers of deaths but decreased age-standardised death rates. Global deaths from injury increased by 10·7%, from 4·3 million deaths in 1990 to 4·8 million in 2013; but age-standardised rates declined over the same period by 21%. For some causes of more than 100 000 deaths per year in 2013, age-standardised death rates increased between 1990 and 2013, including HIV/AIDS, pancreatic cancer, atrial fibrillation and flutter, drug use disorders, diabetes, chronic kidney disease, and sickle-cell anaemias. Diarrhoeal diseases, lower respiratory infections, neonatal causes, and malaria are still in the top five causes of death in children younger than 5 years. The most important pathogens are rotavirus for diarrhoea and pneumococcus for lower respiratory infections. Country-specific probabilities of death over three phases of life were substantially varied between and within regions. Interpretation For most countries, the general pattern of reductions in age-sex specific mortality has been associated with a progressive shift towards a larger share of the remaining deaths caused by non-communicable disease and injuries. Assessing epidemiological convergence across countries depends on whether an absolute or relative measure of inequality is used. Nevertheless, age-standardised death rates for seven substantial causes are increasing, suggesting the potential for reversals in some countries. Important gaps exist in the empirical data for cause of death estimates for some countries; for example, no national data for India are available for the past decade.

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BACKGROUND: Death from acute coronary syndrome (ACS) is avoidable with early reperfusion therapy, however, evidence suggests inequity in women's ACS treatment within a number of international healthcare systems, when compared to men's. Research indicates mortality rates are higher in some age groups of women when compared to men for the sub-group of ACS known as ST-segment elevation myocardial infarction (STEMI). OBJECTIVE: To determine whether patient sex was associated with patterns of reperfusion treatment variation or increased inhospital mortality in patients with STEMI. METHODS: We undertook retrospective analyses on a government database for patients admitted to Victorian public hospitals with STEMI. Patients were categorised into two age groups: 18-64 and 65-84 years (inclusive), to determine whether patient sex and these age groups influenced treatment from 2005 to 2008 and mortality from 2005 to 2010. RESULTS: Both younger and older women received less frequent angioplasty with stent and more often received no reperfusion treatment than men in corresponding younger and older age groups (p=0.006 and p<0.001, respectively). Overall, women in both age groups were more likely to die inhospital than men from equivalent age groups with STEMI (p<0.001, both groups). CONCLUSIONS: Proportionately, both younger and older women received less interventional reperfusion therapy for STEMI than their male cohorts, and died more often during admission than men. Further research needs to be undertaken to verify the findings and causes, and guide future research to ensure application of evidence to treatment in patients with STEMI.

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The partial defence of provocation is one of the most controversial doctrines within the criminal law. It has now been abolished in a number of international jurisdictions. Addressing the trajectory of debates about reform of the provocation defence across different jurisdictions, Sex, Culpability and the Defence of Provocation considers the construction and representation of subjectivity and sexual difference in legal narrations of intimate partner homicide. Undeniably, the most vexing exculpatory cultural narrative of our times is that of a woman 'asking for it'. This book explores how the process of judgment in a criminal trial involves not only the drawing of inferences from the facts of a particular case, but also operates to deliver a narrative. Law, it is argued, constructs a narrative of how the female body incites male violence. And, pursuing an approach that is informed by socio-legal studies, literary theory and feminist theories of the body, Sex, Culpability and the Defence of Provocation considers how this narrative is constructed via a range of discursive practices that position woman as a threat to masculine norms of propriety and autonomy. Once we have a clear understanding of the significance of narrative in legal decision-making, we can then formulate textual strategies of resistance to the violence of law's victim-blaming narratives by rewriting them.