Error, Bias, and Long-Branch Attraction in Data for Two Chloroplast Photosystem Genes in Seed Plants

Sequences of two chloroplast photosystem genes, psaA and psbB, together comprising about 3,500 bp, were obtained for all five major groups of extant seed plants and several outgroups among other vascular plants. Strongly supported, but significantly conflicting, phylogenetic signals were obtained in parsimony analyses from partitions of the data into first and second codon positions versus third positions. In the former, both genes agreed on a monophyletic gymnosperms, with Gnetales closely related to certain conifers. In the latter, Gnetales are inferred to be the sister group of all other seed plants, with gymnosperms paraphyletic. None of the data supported the modern ‘‘anthophyte hypothesis,’’ which places Gnetales as the sister group of flowering plants. A series of simulation studies were undertaken to examine the error rate for parsimony inference. Three kinds of errors were examined: random error, systematic bias (both properties of finite data sets), and statistical inconsistency owing to long-branch attraction (an asymptotic property). Parsimony reconstructions were extremely biased for third-position data for psbB. Regardless of the true underlying tree, a tree in which Gnetales are sister to all other seed plants was likely to be reconstructed for these data. None of the combinations of genes or partitions permits the anthophyte tree to be reconstructed with high probability. Simulations of progressively larger data sets indicate the existence of long-branch attraction (statistical inconsistency) for third-position psbB data if either the anthophyte tree or the gymnosperm tree is correct. This is also true for the anthophyte tree using either psaA third positions or psbB first and second positions. A factor contributing to bias and inconsistency is extremely short branches at the base of the seed plant radiation, coupled with extremely high rates in Gnetales and nonseed plant outgroups. M. J. Sanderson,* M. F. Wojciechowski,*† J.-M. Hu,* T. Sher Khan,* and S. G. Brady

Attention and memory bias for body image and health related information using an Emotional Stroop task in a non-clinical sample

It has been proposed that body image disturbance is a form of cognitive bias wherein schemas for self-relevant information guide the selective processing of appearancerelated information in the environment. This threatening information receives disproportionately more attention and memory, as measured by an Emotional Stroop and incidental recall task. The aim of this thesis was to expand the literature on cognitive processing biases in non-clinical males and females by incorporating a number of significant methodological refinements. To achieve this aim, three phases of research were conducted. The initial two phases of research provided preliminary data to inform the development of the main study. Phase One was a qualitative exploration of body image concerns amongst males and females recruited through the general community and from a university. Seventeen participants (eight male; nine female) provided information on their body image and what factors they saw as positively and negatively impacting on their self evaluations. The importance of self esteem, mood, health and fitness, and recognition of the social ideal were identified as key themes. These themes were incorporated as psycho-social measures and Stroop word stimuli in subsequent phases of the research. Phase Two involved the selection and testing of stimuli to be used in the Emotional Stroop task. Six experimental categories of words were developed that reflected a broad range of health and body image concerns for males and females. These categories were high and low calorie food words, positive and negative appearance words, negative emotion words, and physical activity words. Phase Three addressed the central aim of the project by examining cognitive biases for body image information in empirically defined sub-groups. A National sample of males (N = 55) and females (N = 144), recruited from the general community and universities, completed an Emotional Stroop task, incidental memory test, and a collection of psycho-social questionnaires. Sub-groups of body image disturbance were sought using a cluster analysis, which identified three sub-groups in males (Normal, Dissatisfied, and Athletic) and four sub-groups in females (Normal, Health Conscious, Dissatisfied, and Symptomatic). No differences were noted between the groups in selective attention, although time taken to colour name the words was associated with some of the psycho-social variables. Memory biases found across the whole sample for negative emotion, low calorie food, and negative appearance words were interpreted as reflecting the current focus on health and stigma against being unattractive. Collectively these results have expanded our understanding of processing biases in the general community by demonstrating that the processing biases are found within non-clinical samples and that not all processing biases are associated with negative functionality

‘Live your liberation, don’t lobby for it’ : Australian queer student activists’ perspectives of same-sex marriage

One topic covered in Australian queer university student print media is the legalisation of same-sex marriage. The legalisation of same-sex marriage is currently generating much debate in Western queer communities. Same-sex marriage is legalised in some countries such as, Canada, Spain, the Netherlands and Belgium. It has been outlawed in Australia and most states in the US. Campaigns continue to reverse these restrictions. Other countries, such as the UK and New Zealand allow same-sex civil unions, providing couples with the rights afforded to married couples. There is a range of research documenting queer communities’ attitudes towards this issue (for example Lannutti 2005; Clarke, Burgoyne and Burns 2006; Yep, Lovaas and Elia 2003; Wolfson 1993; Egan and Sherrill 2005). These studies document broad community views as well as those of community sub-sections. For example, Yip (2004) looks at the views of gay and lesbian Christians on same-sex marriage and Lahey and Alderson (2004) document the experiences of same-sex couples who have gotten married or who are waiting to get married. Philosophical analyses consider the legalisation of same-sex marriage in relation to, for example, liberalism, equal rights, liberation, queer theory, citizenship, history, activism, religious discourse and feminism (Ferguson 2007; Jordan 2005; Josephson 2005; Lipton 2006; Sullivan and Chauncey 2005; Riggs 2007). This paper explores Australian queer university student activist media’s representation of same-sex marriage, and the debates surrounding its legalisation. It examines a selection of queer student media from four metropolitan Australian universities, and the 2003 and 2004 editions of national queer student publication, Querelle. This paper uses discourse analysis of queer student activists’ media representations of marriage to investigate this issue in one specific context – metropolitan Australian universities. This paper thus contributes to the history of queer activism, documenting what one group of young people say about the legalisation of same-sex marriage, and furthers research on queer perspectives of marriage and same-sex relationships.

Effect of female sex hormones on Chlamydia trachomatis growth and gene expression

Transmissible diseases are re-emerging as a global problem, with Sexually Transmitted Diseases (STDs) becoming endemic. Chlamydia trachomatis is the leading cause of bacterially-acquired STD worldwide, with the Australian cost of infection estimated at $90 - $160 million annually. Studies using animal models of genital tract Chlamydia infection suggested that the hormonal status of the genital tract epithelium at the time of exposure may influence the outcome of infection. Oral contraceptive use also increased the risk of contracting chlamydial infections compared to women not using contraception. Generally it was suggested that the outcome of chlamydial infection is determined in part by the hormonal status of the epithelium at the time of exposure. Using the human endolmetrial cell line ECC-1 this study investigated the effects of C. trachomatis serovar D infection, in conjunction with the female sex hormones, 17β-estradiol and progesterone, on chlamydial gene expression. While previous studies have examined the host response, this is the first study to examine C.trachomatis gene expression under different hormonal conditions. We have highlighted a basic model of C. trachomatis gene regulation in the presence of steroid hormones by identifying 60 genes that were regulated by addition of estradiol and/or progesterone. In addition, the third chapter of this thesis discussed and compared the significance of the current findings in the context of data from other research groups to improve our understanding of the molecular basis of chlamydial persistence under hormonal different conditions. In addition, this study analysed the effects of these female sex hormones and C. trachomatis Serovar D infection, on host susceptibility and bacterial growth. Our results clearly demonstrated that addition of steroid hormones not only had a great impact on the level of infectivity of epithelial cells with C.trachomatis serovar D, but also the morphology of chlamydial inclusions was affected by hormone supplementation.

Youth, Sex, and Government

For nearly twenty-five years, the field of youth studies has employed the same conceptual tools to explain the conduct of young people, tools that inexorably lead to the same recurrent conclusions-youth equals resistance, youth equals alienation, youth equals problem. This book offers a way out of this theoretical Groundhog Day. Starting with the familiar notion of youth subcultures, but also addressing topics such as young women's magazines, 'at risk' youth, anorexia nervosa, and HIV/AIDS programs, this book examines the way in which youth is produced as both a governmental object and a set of practices of the self. Employing the ideas of Foucault, Rose and Mauss, this new approach attempts to reinvigorate what is an important-yet slumbering-area of research.

A re-assessment of the debate over sex education

The intention of this paper is to call into question the apparent dichotomy between left and right wing positions concerning the implementation of sex education in Queensland Schools. By adopting a more historicised approach, it is suggested that these positions are part of dual and supplementary strategies which work through specific problematisations associated with youth. Accordingly, the emphasis should be shifted from generalised depictions of the adolescent/youth to more focused accounts, questioning how teaching children to manage their sex became a governmental imperative.

Youth, sex, and 'practices of the self'

The intention of this paper is to describe ways of avoiding the normalising, globalising and dichotomising tenor of previous research into 'youth'. With a specific focus upon the management of sex, it will be argued that the concept of 'youth' is best understood as an example of the governmental formation of specific types of person, and that 'youth' can be formulated in terms of 'the doing of certain kinds of work on the self'.

Rethinking Prostitution : feminism, sex and the self

Prostitution is a difficult issue, particularly for feminists. Are prostitutes victims of exploitation or the most honest of women? Are clients perverts or just acting instinctively? Should prostitution be eliminated or supported? This book examines these contemporary questions and offers a way of thinking about the issues, which does not rely on these inappropriate and often ineffectual options. Repositioning the institution and its main players outside the confines of the prostitution debate offers new and exciting ways of thinking and acting for all those interested in moving this discussion into the twenty-first century.

Saving schools from abomination and abnormal sex : a discourse analysis of online public commentary about 'queering' school spaces

Homophobic hatred: these words summarise online commentary made by people in support of a school that banned gay students from taking their same sex partners to a school formal. With the growing popularity of online news sites, it seems appropriate to critically examine how these sites are becoming a new arena in which people can express personal opinions about controversial topics. While commentators equally expressed two dominant viewpoints about the school ban (homophobic hatred and human rights), this paper focuses on homophobic hatred as a discursive position and how the comments work to confirm the legitimacy of the schools’ decision. Drawing on the work of Foucault and others, the paper examines how the comments constitute certain types of subjectivity drawing on dominant ideas about what it means to be homophobic. The analysis demonstrates the complex and competing skein of strategies that constitute queering school social spaces as a social problem.