1000 resultados para CaAl_3BO_7:RE
Resumo:
Edith Penrose’s theory of firm growth postulates that a firm’s current growth rate will be influenced by the adjustment costs of, and changes to a firm’s productive opportunity set arising from, previous growth. Although she explicitly considered the impact of previous organic growth on current organic growth, she was largely silent about the impact of previous acquisitive growth. In this paper we extend Penrose’s work to examine that the relative impact of organic and acquisitive growth on the adjustment costs and productive opportunity set of the firm. Employing a panel of commercially active enterprises in Sweden over a 10 year period our results suggest the following. First, previous organic growth acts as a constraint on current organic growth. Second, previous acquisitive growth has a positive effect on current organic growth. We conclude that organic growth and acquisitive growth constitute two distinct strategic options facing the firm, which have a differential impact on the future organic growth of the firm.
Resumo:
Children’s drawings provide rich qualitative data (Walker, 2008) and “valuable information for the assessment of children's environmental perceptions” (Barraza, 1999, p. 49). They are the primary data source being used to re-imagine school from a student perspective (Schratz & Steiner-Löffler, 1998) in a research project being carried out with primary school students in Queensland, Australia. This paper will report on the progress of this project which addresses a mostly unmet need for students’ perspectives to be included in school design (Rudduck & Flutter, 2004). Grade 5/6 students in a number of primary schools have been invited to submit annotated drawings with up to 200 words of text illustrating their ideal educational spaces. Using purpose-designed analytical tools, the submissions will be compared across student backgrounds and school types to obtain a better understanding of the needs and educational desires of young people in relation to changing learning environments. The findings will inform consideration of the design and use of educational spaces with all work exhibited through a dedicated website. The term ‘educational spaces’ avoids restrictive notions of what the concept of ‘school’ means, referring to any real or virtual space in which teaching and learning may occur or, as Ferguson and Seddon (2007) have referred to it, “the shifting imagery of education” that includes red brick schools and dispersed learning networks. The theoretical framework for this study is grounded in the work of Greene (1995) and Wright-Mills (2001) who cited the deployment of critical and empathic imagination in addressing education reform.
Resumo:
This article reports on the first stage of a study that uses Young People as Researchers methodology to investigate the phenomenon of middle-year student disengagement. The study obtains student perspectives on the meanings of engagement and disengagement using a variety of innovative research methods. The first stage of the study focused on a two-day workshop giving students and teachers an overview of the project and providing training and experience in conducting research in their schools. The process employed by the study provides spaces and resources for critical thinking and encourages imaginative responses to the real life problems confronting the students and their peers and affecting their educational engagement. This article describes ways in which engagement is viewed both theoretically and through the empirical work of the student researchers, and how various applications of ‘disciplined imagination’ connect with methods of investigating and understanding engagement.
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Focusing on the notion of street kids, the paper suggests that youth be viewed in an alternative way to the subculture theory associated with the Center for Contemporary Cultural Studies in Birmingham (CCCS). It is argued that not only is subculture theory an unsuitable mechanism for understanding homeless youth but also, and more importantly, is itself fundamentally problematic. It is suggested that the work of Michel Foucault necessitates a reevaluation of the domain assumptions underlying subculture theory and offers in its place a model that relocates street kids, and youth itself, as artifacts of a network of governmental strategies.
Resumo:
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.
Resumo:
The last few years have seen dramatic advances in genomics, including the discovery of a large number of non-coding and antisense transcripts. This has revolutionised our understanding of multifaceted transcript structures found within gene loci and their roles in the regulation of development, neurogenesis and other complex processes. The recent and continuing surge of knowledge has prompted researchers to reassess and further dissect gene loci. The ghrelin gene (GHRL) gives rise to preproghrelin, which in turn produces ghrelin, a 28 amino acid peptide hormone that acts via the ghrelin receptor (growth hormone secretagogue receptor/GHSR 1a). Ghrelin has many important physiological and pathophysiological roles, including the stimulation of growth hormone (GH) release, appetite regulation, and cancer development. A truncated receptor splice variant, GHSR 1b, does not bind ghrelin, but dimerises with GHSR 1a, and may act as a dominant negative receptor. The gene products of ghrelin and its receptor are frequently overexpressed in human cancer While it is well known that the ghrelin axis (ghrelin and its receptor) plays a range of important functional roles, little is known about the molecular structure and regulation of the ghrelin gene (GHRL) and ghrelin receptor gene (GHSR). This thesis reports the re-annotation of the ghrelin gene, discovery of alternative 5’ exons and transcription start sites, as well as the description of a number of novel splice variants, including isoforms with a putative signal peptide. We also describe the discovery and characterisation of a ghrelin antisense gene (GHRLOS), and the discovery and expression of a ghrelin receptor (growth hormone secretagogue receptor/GHSR) antisense gene (GHSR-OS). We have identified numerous ghrelin-derived transcripts, including variants with extended 5' untranslated regions and putative secreted obestatin and C-ghrelin transcripts. These transcripts initiate from novel first exons, exon -1, exon 0 and a 5' extended 1, with multiple transcription start sites. We used comparative genomics to identify, and RT-PCR to experimentally verify, that the proximal exon 0 and 5' extended exon 1 are transcribed in the mouse ghrelin gene, which suggests the mouse and human proximal first exon architecture is conserved. We have identified numerous novel antisense transcripts in the ghrelin locus. A candidate non-coding endogenous natural antisense gene (GHRLOS) was cloned and demonstrates very low expression levels in the stomach and high levels in the thymus, testis and brain - all major tissues of non-coding RNA expression. Next, we examined if transcription occurs in the antisense orientation to the ghrelin receptor gene, GHSR. A novel gene (GHSR-OS) on the opposite strand of intron 1 of the GHSR gene was identified and characterised using strand-specific RT-PCR and rapid amplification of cDNA ends (RACE). GHSR-OS is differentially expressed and a candidate non-coding RNA gene. In summary, this study has characterised the ghrelin and ghrelin receptor loci and demonstrated natural antisense transcripts to ghrelin and its receptor. Our preliminary work shows that the ghrelin axis generates a broad and complex transcriptional repertoire. This study provides the basis for detailed functional studies of the the ghrelin and GHSR loci and future studies will be needed to further unravel the function, diagnostic and therapeutic potential of the ghrelin axis.
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The arrival of substantial cohorts of English language learners from Africa with little, no or severely interrupted schooling is requiring new pedagogic responses from teachers in Australia and other Western countries of refugee re-settlement. If the students are to have optimal educational and life chances, it is crucial for them to acquire resources for conceptually deep and critical literacy tasks while still learning basic reading and writing skills. This requires teachers to extend their pedagogic repertoires: subject area teachers must teach language and literacy alongside content; high school teachers must teach what has been thought of as primary school curriculum. The aim of this article is to describe some teacher responses to these challenges. Data are drawn from a study involving an intensive language school and three high schools, and also from the author’s experience as a homework tutor for refugees. Stand-alone basic skills programs are described, as are modifications of long-established ESL programs. It is also argued that teachers need to find ways of linking with the conceptual knowledge of students who arrive with content area backgrounds different from others in their class. Everyday life experiences prior to, and after re-settlement in the West, are rich with potential in this regard.
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Background. The objective is to estimate the cost-effectiveness of an intervention that reduces hospital readmission among older people at high risk. A cost-effectiveness model to estimate the costs and health benefits of the intervention was implemented. Methodology/Principal Findings. The model used data from a randomised controlled trial conducted in an Australian tertiary metropolitan hospital. Participants were acute medical admissions aged >65 years with at least one risk factor for readmission: multiple comorbidities, impaired functionality, aged >75 years, 30 recent multiple admissions, poor social support, history of depression. The intervention was a comprehensive nursing and physiotherapy assessment and an individually tailored program of exercise strategies and nurse home visits with telephone follow-up; commencing in hospital and continuing following discharge for 24 weeks. The change to cost outcomes, including the costs of implementing the intervention and all subsequent use of health care services, and, the change to health benefits, represented by quality adjusted life years, were estimated for the intervention as compared to existing practice. The mean change to total costs and quality 38 adjusted life years for an average individual over 24 weeks participating in the intervention were: cost savings of $333 (95% Bayesian credible interval $-1,932:1,282) and 0.118 extra quality adjusted life years (95% Bayesian credible interval 0.1:0.136). The mean net41 monetary-benefit per individual for the intervention group compared to the usual care condition was $7,907 (95% Bayesian credible interval $5,959:$9,995) for the 24 week period. Conclusions/Significance. The estimation model that describes this intervention predicts cost savings and improved health outcomes. A decision to remain with existing practices causes unnecessary costs and reduced health. Decision makers should consider adopting this 46 program for elderly hospitalised patients.
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Journalists in the “new media” era confront important questions as to whether, or how, they adapt their professional practices to a new interactive on-line form that allows citizens to become involved in the news-making process. This paper seeks to re-establish the relevance of traditional journalism practices in the modern era and suggests that they will remain very much a part of the “new journalism” beyond the digital divide. It does so through examining how broadcast journalism interviews challenge authorities in the “public interest”, and suggests, in conclusion, that such practices remain undiminished by the technical, and accompanying social, changes that are driving the “new media”.
Resumo:
The Sydney Harbour Bridge provides an imaginative space that is revisited by Australian writers in particular ways. In this space novelists, poets, and cultural historians negotiate questions of emotional and psychological transformation as well as reflect on social and environmental change in the city of Sydney. The writerly tensions that mark these accounts often alter, or query, representations of the Bridge as a symbol of material progress and demonstrate a complex creative engagement with the Bridge. This discussion of ‘the Bridge’ focuses on the work of four authors, Eleanor Dark, P.R. Stephensen, Peter Carey and Vicki Hastrich and includes a range of other fictional and non-fictional accounts of ‘Bridge-writing.’ The ideas proffered are framed by a theorising of space, especially referencing the work of Michel de Certeau, whose writing on the spatial ambiguity of a bridge is important to the examination of the diverse ways in which Australian writers have engaged with the imaginative potential and almost mythic resonance of the Sydney Harbour Bridge.