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Utilising T cell receptor transgenic mice to define mechanisms of maternal T cell tolerance in pregnancy
No full textStudies in mice demonstrate that the maternal T cell repertoire is aware of paternal antigens during pregnancy, but in healthy pregnancy reactive T cells do not mediate anti-fetal immunity. Mice expressing transgenic T cell receptors (TCRs) specific for paternal and conceptus antigens are powerful tools for elucidating the events surrounding paternal antigen presentation to the maternal T cell repertoire, the nature of the ensuing T cell response and the factors that skew the response towards immune tolerance to allow survival and development of the conceptus. While results from different transgenic TCR models are not always consistent, there is now sufficient data to allow a consensus interpretation that maternal antigen presenting cells present initially seminal fluid antigens and later placenta-derived antigens to both the CD4+ and CD8+ T cell repertoire. T cell proliferation is generally followed by entry into a state of anergy demonstrated by decreased cytokine production and hyporesponsiveness upon restimulation. Some models also demonstrate downregulation of the TCR and co-stimulatory molecules, clonal deletion of paternal antigen-reactive T cells, or alternatively T cell ignorance of paternal antigens. This review will summarise the range of transgenic TCR studies that have shed light on the events surrounding paternal antigen presentation and the various T cell responses to insemination and pregnancy. The benefits, limitations and caveats of these models, and their impact upon data interpretation, are discussed.
National female literacy, individual socio-economic status, and maternal health care use in sub-Saharan Africa
No full textThe United Nations Millennium Development Goals have identified improving women’s access to maternal health care as a key target in reducing maternal mortality in sub-Saharan Africa (sSA). Although individual factors such as income and urban residence can affect maternal health care use, little is known about national-level factors associated with use. Yet, such knowledge may highlight the importance of global and national policies in improving use. This study examines the importance of national female literacy on women’s maternal health care use in continental sSA. Data that come from the 2002–2003 World Health Survey. Multilevel logistic regression was used to examine the association between national female literacy and individual’s non-use of maternal health care, while adjusting for individual-level factors and national economic development. Analyses also assessed effect modification of the association between income and non-use by female literacy. Effect modification was evaluated with the likelihood ratio test (G2). We found that within countries, individual age, education, urban residence and household income were associated with lack of maternal health care. National female literacy modified the association of household income with lack of maternal health care use. The strength of the association between income and lack of maternal health care was weaker in countries with higher female literacy. We conclude therefore that higher national levels of female literacy may reduce income-related inequalities in use through a range of possible mechanisms, including women’s increased labour participation and higher status in society. National policies that are able to address female literacy and women’s status in sub-Saharan Africa may help reduce income-related inequalities in maternal health care use.
Coagulation assessment and optimisation with a photometric dispersion analyser and organic characterisation for natural organic matter removal performance
No full textThree South Australian source waters of low, mid and high dissolved organic carbon (DOC) levels were evaluated for coagulation efficiency in terms of natural organic matter (NOM) interaction and floc behaviour. Experiments were conducted using aluminium chlorohydrate (ACH) and aluminium sulphate (alum) at different mixing conditions with continuous monitoring of formation and breakage of flocs using a flow-through optical measurement device known as photometric dispersion analyser (PDA). A positive correlation of floc growth against coagulant dosage was found for ACH based on a limiting growth function. Floc structure was assessed by analysis of PDA derived parameters showing promise for more rapid coagulation condition optimisation than subjective visual criteria. Removal of NOM and growth of flocs are influenced more by the hydrophobicity of the NOM than the choice of coagulant. A higher hydrophobic fraction resulted in slower aggregation of flocs with both coagulants and better removal when using alum at controlled pH.
Effective teaching of the physical design of integrated circuits using educational tools
No full textLong-haul pilots use in-flight napping as a countermeasure to fatigue
No full textThe aim of this study was to examine the effects of fatigue on the amount of in-flight sleep obtained by airline pilots during long-haul duty periods. A total of 301 pilots collected sleep/wake and work/rest data for a period of at least 2 weeks each. Fatigue likelihood, i.e. low, moderate, high, or extreme, was estimated for each duty period based on a pilot’s sleep/wake behaviour prior to duty and the time of day that the duty period occurred. Participants obtained 1.8 h of sleep (i.e. 27% of their rest time) during duty periods with low fatigue likelihood and 3.7 h of sleep (i.e. 54% of their rest time) during duty periods with extreme fatigue likelihood. These results indicate that (i) long-haul pilots obtain substantially more sleep during duty periods when fatigue is likely to be extreme than when fatigue is likely to be low and (ii) long-haul pilots use in-flight napping as a fatigue countermeasure, but more could be done to increase its efficacy.
Because looks can be deceiving : media alarm and the sexualisation of childhood : do we know what we mean?
No full textThis article considers ongoing moral outrage over the assumed sexualisation of young girls by the media. It questions this taken-for-granted association between the media and the sexualisation of children. It suggests that this visceral anxiety reflects a particularly adult-centric view of children's behaviour and considers how this may serve to discipline girls' sexuality in particular. Whilst child welfare and wellbeing are paramount, this article suggests the need for a more nuanced and ethnographically informed debate around the relationship between childhood, the media, and sexualisation. It calls for ethnographic research with children, to understand their perspectives of what adults view as sexualised behaviour. A number of questions are raised throughout the article to stimulate further research within anthropology and the social sciences more broadly. The article considers the extent to which attention could more usefully be shifted from the control of extrinsic factors such as the media to teaching critical thinking skills in primary and secondary schooling. It thus argues for a critical anthropological engagement with a debate currently dominated by adult-centric understandings and framed against a demonisation of sexuality and the media.
Evaluation of the continuous wavelet transform for feature extraction of metal detector signals in automated target detection
No full textLandmines pose a significant problem in many countries around the world. Although technological systems such as metal detectors have been employed to combat these threats, many of these still require significant human interaction especially in the area of target and clutter discrimination. The aim of this research is to develop an automated decision making system for landmine detection. The initial stages of the research involves comparing various techniques for feature extraction to determine which methods provide the best representation for metal detector data to achieve improved target discrimination from background noise. This paper will focus on evaluating a technique utilizing the Continuous Wavelet Transform with false alarm rate and probability of detection used as performance measures.
Introducing peer review and assessment within a project based learning framework to account for difficulty
No full textIn this paper, we report on a longitudinal study into instruction in a technology based course directed at the creation of multimedia applications. Students come from both the Computing and Media Arts areas and group project work has been the main assessment strategy employed. A metric referred to as the Difficulty was arrived at through a factor analysis of questionnaire data. This metric has been the focus of successive offerings of this action research. A disparity in this metric between students groups became evident and efforts have been employed in subsequent iterations of the course to appease these differences. The project based instructional methodology that has been employed, is characterised by the giving of control over to the students during the development process. Peer review and assessment were also embedded within the instructional methodology to both provide exemplars of work conducted and subsequent feedback, and equity within the assessment process. A number of assessment rubrics were introduced to aid in this process. Interestingly, the end result was an movement on the Difficulty factor for the Computing students. Both cohorts agreed that the instructional methodology was satisfactory.