Identification of novel genes differentially expressed in haemopoietic progenitor cells

The biochemical and molecular processes that maintain the stem cell pool, and govern the proliferation and differentiation of haemopoietic stem/progenitor cells (HSPCs) have been widely investigated but are incompletely understood. The purpose of this study was to identify and characterise novel genes that may play a part in regulating the mechanisms that control the proliferation, differentiation and self-renewal of human HSPCs. Reverse transcription differential display polymerase chain reaction (dd-PCR) was used to identify differences in gene expression between a HSPC population defined by expression of the CD34 phenotype, and the more mature CD34 depleted populations. A total of 6 differentially expressed complementary deoxyribonucleic acid (cDNA) sequences were identified. Four of these transcripts were homologous to well characterised genes, while two (band 1 and band 20) were homologous to unknown and uncharacterised partial gene sequences on the GenBank database and were thus chosen for further investigation. The partial cDNA sequences for band 1 and band 20 were designated ORP-3 and MERP-1 (respectively) due to homologies with other well-characterised gene families. Differential expression of the ORP-3 and MERP-1 genes was confirmed using Taqman™ real-time polymerase chain reaction (PCR) with 3 - 4-fold and 4-10 -fold higher levels in the CD34+ fractions of haemopoietic cells compared to CD34- populations respectively. Additionally, expression of both these genes was down regulated with proliferation and differentiation of CD34+ cells further confirming higher expression in a less differentiated subset of haemopoietic cells. The full coding sequences of ORP-3 and MERP-1 were elucidated using bioinformatics, rapid amplification of cDNA ends (RACE) and PCR amplification. The MERP-1 cDNA is 2600 nucleotides (nt) long, and localizes by bioinformatics to chromosome 7.. It consists of three exons and 2 introns spanning an entire length of 31.4 kilobases (kb). The MERP-1 open reading frame (ORF) codes for a putative 344 amino acid (aa) type II transmembrane protein with an extracellular C-terminal ependymin like-domain and an intracellular N-terminal sequence with significant homology to the cytoplasmic domains of members of the protocadherin family of transmembrane glycoproteins. Ependymins and protocadherins are well-characterised calcium-dependant cell adhesion glycoproteins. Although the function of MERP-1 remains to be elucidated, it is possible that MERP-1 like its homologues plays a role in calcium dependent cell adhesion. Differential expression of the MERP-1 gene in haemopoietic cells suggests a role in haemopoietic stem cell proliferation and differentiation, however, its broad tissue distribution implies that it may also play a role in many cell types. Characterization of the MERP-1 protein is required to elucidate these possible roles. The ORP-3 cDNA is 6631nt long, and localizes by bioinformatics to chromosome 7pl5-p21. It consists of 23 exons and 22 introns spanning an entire length of 183.5kb. The ORP-3 ORF codes for a putative 887aa protein which displays the consensus sequence for a highly conserved oxysterol-binding domain. Other well-characterised proteins expressing these domains have been demonstrated to bind oxysterols (OS) in a dose dependant fashion. OS are hydroxylated derivatives of cholesterol Their biological activities include inhibition of cholesterol biosynthesis and cell proliferation in a variety of cell types, including haemopoietic cells. Differential expression of the ORP-3 gene in haemopoietic cells suggests a possible role in the transduction of OS effects on haemopoietic cells, however, its broad tissue distribution implies that it may also play a role in many cell types. Further investigation of ORP-3 gene expression demonstrates a significant correlation with CD34+ sample purity, and 2-fold higher expression in a population of haemopoietic cells defined by the CD34+38- phenotype compared to more mature CD34+38+ cells. This finding, taken together with the previous observation of down-regulation of ORP-3 expression with proliferation and differentiation of CD34+ cells, indicates that ORP-3 expression may be higher in a less differentiated subset of cells with a higher proliferative capacity. This hypothesis is supported by the observation that expression of the ORP-3 gene is approximately 2-fold lower in differentiated HL60 promyelocytic cells compared to control, undifferentiated cells. ORP-3 expression in HL60 cells during normal culture conditions was also found to vary with expression positively correlated with cell number. This indicates a possible cell cycle effect on ORP-3 gene expression with levels highest when cell density, and therefore the percentage of cells in G(0)/G(1) phase of the cell cycle is highest. This observation also correlates with the observation of higher ORP-3 expression in CD34+38-cells, and in CD34+ and HL60 cells undergoing OS induced and camptothecin induced apoptosis that is preceded by cell cycle arrest at G(0)/G(1). Expression of the ORP-3 gene in CD34+ HSPCs from UCB was significantly decreased to approximately half the levels observed in control cells after 24 hours incubation in transforming growth factor beta-1 (TGFâl). As ≥90% of these cells are stimulated into cell cycle entry by TGFâl, this observation further supports the hypothesis that ORP-3 expression is highest when cells reside in the G(0)/G(1) phase of the cell cycle. Data obtained from investigation of ORP-3 gene expression in synchronised HL60 cells however does not support nor disprove this hypothesis. Culture of CD34+ enriched HSPCs and HL60 cells with 25-OHC significantly increased ORP-3 gene expression to approximately 1.5 times control levels. However, as 25-OHC treatment also increased the percentage of apoptotic cells in these experiments, it is not valid to make any conclusions regarding the regulation of ORP-3 gene expression by OS. Indeed, the observation that camptothecin induced apoptosis also increased ORP-3 gene expression in HL60 cells raises the possibility that up-regulation of ORP-3 gene expression is also associated with apoptosis, Taken together, expression of the ORP-3 gene appears to be regulated by differentiation and apoptosis of haemopoietic progenitors, and may also be positively associated with proliferative and G(0)/G(1) cell cycle status indicating a possible role in all of these processes. Given the important regulatory role of apoptosis in haemopoiesis and differential expression of the ORP-3 gene in haemopoietic progenitors, final investigations were conducted to examine the effects OS on human HSPCs. Granulocyte/macrophage colony forming units (CFU-GM) generated from human bone marrow (ABM) and umbilical cord blood (UCB) were grown in the presence of varying concentrations of three different OS - 7keto-cholesterol (7K-C), 7beta-hydroxycholesterol (7p-OHC) and 25-hydroxycholesterol (25-OHC). Similarly, the effect of OS on HL60 and CD34+ cells was investigated using annexin-V staining and flow cytometry to measure apoptosis. Reduction of nitroblue tetrazolium (NBT) was used to assess differentiative status of HL60 cells. CFU-GM from ABM and HL60 growth was inhibited by all three OS tested, with 25-OHC being the most potent. 25-OHC inhibited ≥50% of bone marrow CFU-GM and ≥95% of HL60 cell growth at a level of 1 ug/ml. Compared to UCB, CFU-GM derived from ABM were more sensitive to the effects of all OS tested. Only 25-OHC and 7(5-OHC significantly inhibited growth of UCB derived CFU-GM. OS treatment increased the number of annexin-V CD34+ cells and NBT positive HL60 cells indicating that OS inhibition of CFU-GM and HL60 cell growth can be attributed to induction of apoptosis and differentiation. From these studies, it can be concluded that dd-PCR is an excellent tool for the discovery of novel genes expressed in human HSPCs. Characterisation of the proteins encoded by the novel genes ORP-3 and MERP-1 may reveal a regulatory role for these genes in haemopoiesis. Finally, investigations into the effects of OS on haemopoietic progenitor cells has revealed that OS are a new class of inhibitors of HSPC proliferation of potential relevance in vivo and in vitro.

Virulence determinants of infectious bursal disease virus

The very virulent (vv) pathotype of infectious bursal disease virus (IBDV) has spread rapidly throughout Europe, Asia, and the Middle East. Although Australia is currently unaffected, there remains the potential for incursion of an exotic isolate. The aim of this study was to identify putative virulence determinants of IBDV to facilitate the development of improved diagnostic assays for detection and characterisation of vvIBDV isolates. Sequencing of Indonesian vvIBDV Tasik94 revealed a unique substitution [ A�¨S222] in the hypervariable region (HVR) of viral protein (VP) VP2, which did not appear to impinge on virulence or antigenicity. Phylogenetic analyses indicated that Tasik94 was closely related to Asian and European vvIBDV strains. Extensive alignment of deduced protein sequences across the HVR of VP2 identified residuesI242 I256 and I294 as putative markers of the vv phcnotype. Comparison of the pathology induced by mildly-virulent Australian IBDV 002/73 and Indonesian vvIBDV Tasik94, revealed that histological lesions in the spleen, thymus and bone marrow were restricted to Tasik94-infected birds, suggesting the enhanced pathogenicity of vvIBDV might be attributed to replication in non-bursal lymphoid organs. The biological significance of the VP2 HVR in virulence was assessed using recombinant viruses generated by reverse genetics. Both genomic segments of Australian IBDV 002/73, and recombinant segment A constructs in which the HVR of 002/73 was replaced with the corresponding region of either tissue culture-adapted virus or vvIBDV (Tasik94), were cloned behind T7 RNA polymerase promoter sequences. In vitro transcription/translation of each construct resulted in expression of viral proteins. Co-transfection of synthetic RNA transcripts initiated replication of both tissue culture-adapted parental and recombinant viruses, however attempts to rescue non-adapted viruses in specific-pathogen-free (SPF) chickens were unsuccessful. Nucleotide sequence variation in the HVR of VP2 was exploited for the development of a new diagnostic assay to rapidly detect exotic IBDV isolates, including vvIBDV, using reverse transcription polymerase chain reaction (RT-PCR) amplification and Bmrl restriction enzyme digestion. The assay was capable of differentiating between endemic and exotic IBDV in 96% of 105 isolates sequenced to date.

On-campus students' learning in asynchronous environments

Asynchronous online discussions have the potential to improve learning in universities. This thesis reports an investigation into the ways in which undergraduates learned in online discussions when they were included within their face-to-face courses. Taking a student perspective, four case studies describe and explain the approaches to learning that were used by business undergraduates in online discussions, and examine the influence of the computer-mediated conferencing (CMC) medium and curriculum design on student learning. The investigation took a qualitative approach where case studies were developed from multiple data sources. In each of the cases, a description of the setting of the online discussions introduced the learning environment. Further details of student learning behaviours in the online discussions were provided by an analysis of the systems data and a content analysis of the online discussion transcripts. In depth interpretation of interview data added student perspectives on the impact of CMC characteristics, the curriculum or learning design and the relationship between the online discussions and face-to-face classes. A comparative cross case analysis of the findings of the four cases identified and discussed general themes and broad principles arising from the cases. The campus-based students acknowledged that online discussions helped them to learn and their message postings evidenced deep approaches to learning. The students recognised the value for learning of the text based nature of the CMC environment but peer interaction was more difficult to achieve. Asynchronicity created time flexibility and time for reflection but it also presented time management problems for many undergraduates. Assessment was the most influential aspect of the curriculum design. The cases also identified the importance of a dialogical activity and the absence of the teacher from the online discussions was not problematic. The research identified new perspectives on the relationship between online discussions and face-to-face classes. Students regarded these two media as complementary rather than oppositional and affirmed the importance of pedagogic connections between them. A teaching and learning framework for online discussions was developed from these perspectives. The significance of this study lies in improved knowledge of student learning processes in online discussions in blended learning environments. The cases indicated the potential value of the CMC environment for constructivist philosophies and affirm the significant role of curriculum design with new technologies. Findings relating to the complementary nature of online and face to face discussions provided a platform for building a teaching and learning framework for blended environments which can be used to inform and improve pedagogical design, teacher expertise and student learning outcomes in asynchronous online discussions.

Music video and gendered pleasures in the lives of young women and men

The purpose of this thesis is to explore the cultural and social significance of music video in the lives of a group of young women and men. In so doing the thesis pays particular attention to issues of gender and pleasure. This research examines the interaction of a group of young people with music video in relation to four areas of research. Firstly, the importance of music video in terms of social interaction and the pleasure this entails is explored. Secondly the thesis looks at the ways in which gender is seen by the young people in this study to be established by music video performers. Thirdly, how gender becomes inscribed on the body is explored, and fourthly I examine the process of sexualization of the body. Theoretically this thesis draws upon feminist theory, poststructuralist theory, music video scholarship and educational theories. This eclectic approach has been necessary as this research speaks simultaneously to several distinct areas of scholarship: education, cultural studies and feminism. My research with a young audience of music video took place within a secondary school. Over two semesters I conducted research with two separate classes of Media Studies students who were aged fifteen and sixteen. A total of 49 students were interviewed, however I chose mainly to work with a small group of eleven students - five girls and six boys. The school where I conducted this research is located in a working class suburb of a provincial and industrial Australian city . The young people's social positioning in terms of class and ethnicity has been considered in some depth in relation to the construction of the gendered subject. Methodologically the thesis is skewed towards the audience, and also towards dealing with what is normally unspoken in the research process. For example, much academic research does not include the author of the research as an integral part of that research. In this thesis I include myself in a number of ways: historically, personally and as a feminist. This thesis places a high priority on ethics and the effects of research on those who participate in the research process. The thesis uses a number of research methods: structured interviews, informal conversations, memory-work and written responses to music videos. Generally the research methods used in this thesis have been developed reflexively; that is, they have developed directly in relation to the participants’ reactions, responses, suggestions, interests and comments. The research seeks to demonstrate the place of music video in the lives of the young people who participated in the study. I look at how the young people in this study connect music video to other cultural forms and social interactions. In this way the intertextuality of music video is demonstrated. The research looks at how young viewers 'read' the gender of music video performers, and how this affects their own gendering. The social and cultural meanings which are attached to certain parts of the body are also examined. Theorizing the body in terms of its social meanings is a significant part of this thesis. The research argues that young people often experience music video as pleasurable, and that music video can provide young people with access to powerful speaking positions. This is demonstrated through transcripts of our conversations and interviews, and also through the young people's written comments. However, these powerful speaking positions invariably invoke dominant discourses (homophobia and racism, for example). Thus the disruptive potential of music video is called into question. These dominant discourses are gendered in nature. Pleasure in the text (music video) and cultural inscriptions of gender on the body then, are realized differently for the girls and for the boys in this study. My research into music video, gender and young people has implications for research methodology generally, and for music video scholarship specifically. Music video scholarship to date has rarely focussed upon the audience of this cultural form. My research has certain implications for the ways in which research is currently conducted with young people in relation to popular culture generally, and music video specifically, and gendered subjectivity.

Repair and tolerance of DNA damage in higher plants

DNA repair mechanisms constitute an essential cellular response to DNA damage arising either from metabolic processes or from environmental sources such as ultraviolet radiation. Repair of these lesions may be via direct reversal, or by processes such as nucleotide excision repair (NER), a coordinated pathway in which lesions and the surrounding nucleotides are excised and replaced via DNA resynthesis. The importance of repair is illustrated by human disease states such as xeroderma pigmentosum and Cockayne's syndrome which result from defects in the NER system arising from mutations in XP- genes or XP- and CS- genes respectively Little detail is known of DNA damage repair processes in plants, despite the economic and ecological importance of these organisms. This study aimed to expand our knowledge of the process of NER in plants, largely via a polymerase chain reaction (PCR)-based approach involving amplification, cloning and characterisation of plant genomic DNA and cDNA. Homologues of the NER components XPF/RAD1 and XPD/RAD3 were isolated as both genomic and complete cDNA sequences from the model dicotyledonous plant Arabidopsis thaliana. The sequence of the 3'-untranslated region of atXPD was also determined. Comparison of genomic and cDNA sequences allowed a detailed analysis of gene structures, including details of intron/exon processing. Variable transcript processing to produce three distinct transcripts was found in the case of atXPF. In an attempt to validate the proposed homologous function of these cDNAs, assays to test complementation of resistance to ultraviolet radiation in the relevant yeast mutants were performed. Despite extensive amino acid sequence conservation, neither plant cDNA was able to restore UV-resistance. As the yeast RAD3 gene product is also involved in vivo in transcription, and so is required for viability, the atXPD cDNA was tested in a complementation assay for this function in an appropriate yeast mutant. The plant cDNA was found to substantially increase the viability of the yeast mutant. The structural and functional significance of these results is discussed comparatively with reference to yeast, human and other known homologues. Other putative NER homologues were identified in A. thaliana database sequences, including those of ERCC1/RAD10 and XPG/ERCC5/RAD2, and are now the subjects of ongoing investigations. This study also describes preliminary investigations of putative REVS and RAD30 translesion synthesis genes from A. thaliana.

The impact of caring for a child with cerebral palsy : quality of life for mothers and fathers

Background:  Although it is expected that caring for a child with cerebral palsy (CP) can impact on the quality of life (QOL) of caregivers, the QOL of carers' has yet to be adequately examined. The aims of this study are to: (1) explore the QOL of mothers and fathers of children with CP aged 3–18 years; and (2) examine whether the impact of caring for a child with CP changes from childhood to adolescence.

Method: A qualitative study was conducted utilizing a grounded theory framework. Twenty-four mothers and 13 fathers of children and adolescents with CP aged 3–7 years (n = 15), 8–12 years (n = 10) and 13–18 years (n = 12) and with varying levels of impairment (GMFCS Level I = 1, II = 4, II = 3, IV = 5, V = 12) participated in semi-structured interviews about their QOL. The transcripts were analysed to identify issues affecting parental QOL.

Results: There were no differences in parental QOL among subgroups (i.e. mothers and fathers, age groups, GMFCS levels). Parental QOL ranged across a wide spectrum. Caring for a child with CP affects a parent's physical well-being, social well-being, freedom and independence, family well-being and financial stability. Parents indicated that they often feel unsupported by the services they access.

Conclusions: Caring for a child with CP can both positively and negatively impact on a parent's life. There is value for both parents and children if parental concerns and determinants of QOL are considered in overall programme planning and service delivery for children and their families.

Perspectives of a nurse, a social-worker and a psychiatrist, regarding patient assessment in acute inpatient psychiatry settings : a case study approach

This case study explores what informs and organizes the assessment of patients, as undertaken by a nurse, a social worker and a psychiatrist in public, metropolitan, acute mental health service settings. The research data are the transcripts of in-depth interviews with three experienced practitioners, one from each of the three disciplines. The analysis draws on Foucauldian concepts: discourse as constructed through practices of discipline and the gaze. We explored examples of taken-for-granted assessment practices and their interplay with discourse. The findings suggest that participating practitioners use language in assessment in ways that support the powerful discourses of the professional disciplines. The competing discourse of management, associated with industry and economics, is evident in hospital admission processes, dictating the times and places of assessment. Professional and management discourses both effectively marginalize the perspective of another player in assessment, the patient.

Communicating the 'unspeakability' of violent acts in cinema

This paper explores the forensic testimony employed in James Benning‟s experimental narrative film Landscape Suicide (1986, 16mm, 95min USA). As a belated example of Judith Walker‟s „Trauma Cinema‟, this film in part re-enacts the court transcripts of two perpetrators of physical violence: Ed Gein and Michelle Protti. Teenager Protti killed another student with a kitchen knife after having been subjected to bullying by a group of girls and Wisconsin farmer Gein shot a storekeeper‟s wife, took the body home to then skin and dissect it. Gein‟s case is said to have provided the model for the cinematic serial killers portrayed in Psycho (1959), The Silence of the Lambs (1991) and Texas Chainsaw Massacre (1974). In its strategy of communicating or representing the overwhelming and traumatic impact of violence cinematically Landscape Suicide is contrasted to the melodrama and shock of mainstream violence in Psycho, Texas Chainsaw Massacre and Silence of the Lambs for its ability to identify „unspeakable‟ aspects of overwhelming experience. This paper will concentrate on the representation of Ed Gein‟s violent acts, rather than Protti‟s and enlists recent neurological research that suggests a model for forgetting that is identifiable in the film‟s structure and content.

Mucosal vascular addressin cell adhesion molecule-1 is expressed outside the endothelial lineage on fibroblasts and melanoma cells

Mucosal vascular addressin cell adhesion molecule-1 (MAdCAM-1) is predominantly expressed on high endothelial venules in inflamed tissues where it assists with leucocyte extravasation. Here we report that MAdCAM-1 has the potential to be more widely expressed outside the endothelial cell lineage than previously appreciated. Thus, MAdCAM-1 RNA transcripts and cell-surface protein were expressed by NIH 3T3 fibroblasts following activation with tumour necrosis factor-alpha (TNF-alpha), and by freshly isolated and cultured primary mouse splenic and tail fibroblasts in the absence of TNF-alpha stimulation. They were constitutively expressed by B16F10 melanoma cells, and expression was enhanced by cell activation with TNF-alpha. Mucosal vascular addressin cell adhesion molecule-1 was expressed on the apical surface of isolated cells, but became predominantly localized to cell junctions in confluent cell monolayers, suggesting it may play a role in the homotypic aggregation of cells. Tumour necrosis factor-alpha enhanced the expression of a firefly luciferase reporter directed by the MAdCAM-1 promoter in NIH 3T3 and B16F10 cells. A DNA fragment extending from nt -1727 to -673 was sufficient to confer cell-type selective expression. Mucosal vascular addressin cell adhesion molecule-1 expressed by NIH 3T3 cells was biologically active, as it supported the adhesion of TK-1 T cells in an alpha4beta7-dependent fashion. The expression of MAdCAM-1 by fibroblasts, and melanomas suggests MAdCAM-1 may play a role in regulating host responses in the periphery, leucocyte transmigration across nonendothelial boundaries, or the homotypic interactions of some malignant melanomas.

Female-perpetrated child sexual abuse

Research has shown that female-perpetrated child sexual abuse is under-recognised. Three studies were undertaken concerning victims' experiences, professional perspectives and court sentencing transcripts. These studies found that victim impact was significant; professionals considered the phenomenon less serious than male sexual offending; and that female sexual offenders were dealt with less harshly than male offenders within the criminal justice system. The portfolio examines four case studies concerning adult females who have reported a history of child sexual abuse within the context of a dual-diagnosis counselling agency and investigates both psychological and behavioural difficulties revealed by each of the young women.

Stories seldom told

This hermeneutic phenomenological study explored paediatric nurses' experiences of caring for hospitalised children with special needs and their families. Four experienced paediatric nurses were interviewed and the transcripts analysed thematically using a Gadamerian hermeneutic approach.

First-year law students’ construction of professional identity through writing

While there is a considerable body of research on law student identity construction based on interviews and transcripts of classroom talk, there is very little work based on student written texts. In this article two letters of advice written by beginning law students are analysed, using Ivanic and Camps’s (2001) framework, as an example of identity formation. Legal identity is argued to be formed by students’ attempts to accommodate a dynamic, partial, practitioner role of provider of advice to the traditional analytic focus of the law student. The process of accommodation is evident in the language of the letters, which show disfluencies resulting from attempts to combine different roles into a coherent legal identity. Comparison with a professionally written letter suggests that, rather than seeking to shape a coherent position, lawyers are able simultaneously to hold incompatible perspectives, concealing the tensions by foregrounding some perspectives and backgrounding others.

Developing english skills through reflective portfolios in Hong Kong universities

This research concerns the use of portfolios by teachers of English (L2) to assist non-native speakers in Hong Kong universities to complete their studies in English. Portfolios as an English learning tool have yet to win converts from the ranks of language teachers in Hong Kong chiefly because of concerns about reliability and fairness. Two recent initiatives in Hong Kong have, however, prompted a reappraisal of the place of portfolios in English language learning. They include the use of learning portfolios in secondary school and ePortfolios by university students for learning and employment purposes.

As an English (L2) teacher of many years, I initiated my research to investigate the experiences of seven university students in Hong Kong in using reflective portfolios for English learning. Three research questions framed my research: 1) in what ways can reflective portfolios impact on L2 learning strategies? 2) what are the effects of reflective portfolios on progress in L2 acquisition as perceived by students? 3) what are the perceptions of university students towards reflective portfolios as a method of L2 learning?

To gain a holistic understanding of the complex phenomena under scrutiny, a case study methodology and grounded theory were utilised, the former to organise and generate qualitative data, and the latter to analyse data from three sources provided by the seven participating students: semi-structured interviews, portfolio artefacts, and weekly learning diaries.

There were two levels of data analysis. For the first level, analysis focused on coded data from portfolio artefacts, diary entries and interview transcripts as reported by students. The second level involved analysis from the Confucian and sociocultural perspectives. I pursued interpretation and continuous refinement of the data by using techniques drawn from grounded theory. The findings revealed that students generally employed a wide spread of L2 learning strategies in the cognitive, meta-cognitive, and socio-affective domain, reported increased awareness of effective language strategies, and considered portfolios a means of supporting time management and record-keeping, and a site for extended writing practice through reflection.

The findings suggest that students display a cyclical, context-specific shift in learning conception from quantitative to qualitative. Connected to this is students’ apparent ability to formulate strategic responses to externally imposed demands. It is found that such responses are culturally triggered, underpinned by Confucian beliefs. Although the Confucian tradition emphasises respect for established authority, the findings point to students’ creative re-configuration of mental schemata to engender change in role enactment and power relations, with the portfolio as a mediating tool of their experiences.

Based on the findings, I argue that my research has addressed the three research questions and contributed to two crucial aspects of L2 learning. The first pertains to the need for a balanced view of individual effort and social context in second language acquisition, corroborating the significant link between context and learner engagement. Another contribution centres on an enhanced understanding of the relationship between portfolios, reflection and L2, where students’ diaries in English and portfolio artefacts enable them to engage in critical reflection and to identify strategies for L2 improvement.

Lunchroom to boardroom : an audio digitization project

The University of Queensland Cybrary in partnership with the Distributed Systems Technology Centre (DSTC), has created a searchable, web based digital oral history resource, based on a collection of stories of women involved in the Queensland Labor movement. A Trades and Labour Council of Queensland oral history collection was used to develop a framework for retrieval of audio materials on the web. A system for linking digitized media files to indexes created from transcripts (Meggie) has been developed. This allows the media file itself to be searched via key words. A trial was conducted and work is now proceeding on completing the collection. The final product will be made available via the Library's web site. The process followed, the choices made, the problems overcome, and the results achieved, will be outlined.

Understanding children's sedentary behaviour : a qualitative study of the family home environment

Electronic media (EM) (television, electronic games and computer) use has been associated with overweight and obesity among children. Little is known about the time spent in sedentary behaviour (SB) among children within the family context. The aim of this study was to explore how the family home environment may influence children's electronic-based SB. Focus groups and family interviews were conducted with 11- to 12-year old children (n = 54) and their parents (n = 38) using a semi-structured discussion guide. Transcripts were analysed using a thematic content approach. A brief self-completed questionnaire was also used to measure leisure behaviour and electronic devices at home. Children incorporated both sedentary and physical activities into their weekly routine. Factors influencing children's EM use included parent and sibling modelling and reinforcement, personal cognitions, the physical home environment and household EM use rules and restrictions. Participants were not concerned about the excessive time children spent with EM. This under-recognition emerged as a personal influencing factor and was viewed as a major barrier to modifying children's electronic-based SB. Efforts to reduce SB in children should focus on the influencing factors that reciprocally interact within the family home. An emphasis on increasing awareness about the risks associated with spending excessive time in screen-based activities should be a priority when developing intervention strategies aimed at modifying the time children spend in SB.