949 resultados para Réaction de Curtis
Resumo:
Developmental progression and differentiation of distinct cell types depend on the regulation of gene expression in space and time. Tools that allow spatial and temporal control of gene expression are crucial for the accurate elucidation of gene function. Most systems to manipulate gene expression allow control of only one factor, space or time, and currently available systems that control both temporal and spatial expression of genes have their limitations. We have developed a versatile two-component system that overcomes these limitations, providing reliable, conditional gene activation in restricted tissues or cell types. This system allows conditional tissue-specific ectopic gene expression and provides a tool for conditional cell type- or tissue-specific complementation of mutants. The chimeric transcription factor XVE, in conjunction with Gateway recombination cloning technology, was used to generate a tractable system that can efficiently and faithfully activate target genes in a variety of cell types. Six promoters/enhancers, each with different tissue specificities (including vascular tissue, trichomes, root, and reproductive cell types), were used in activation constructs to generate different expression patterns of XVE. Conditional transactivation of reporter genes was achieved in a predictable, tissue-specific pattern of expression, following the insertion of the activator or the responder T-DNA in a wide variety of positions in the genome. Expression patterns were faithfully replicated in independent transgenic plant lines. Results demonstrate that we can also induce mutant phenotypes using conditional ectopic gene expression. One of these mutant phenotypes could not have been identified using noninducible ectopic gene expression approaches.
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The holistic conception of the troika, as described in the first chapter, centres on the relationship between the implicit and explicit teaching of values the nurturing of the specific dimensions of quality teaching and the opportunity to ‘walk the talk’ of the values education program through aspects such as practical citizenship (Lovat, Toomey, Clement, Crotty & Nielsen, 2009). It is proposed in this chapter that the conception can be realized through the embedding of Philosophy in the Classroom within pre-service teaching programs. The troika, a Russian sleigh with three horses, only function well when there is complete synergy and balance between all Classroom is a scaffold for ensuring that all three elements of the troika, namely, quality teaching, values education and service learning in the form of education for citizenship, exist within the classroom to achieve an optimal learning, growth and wellbeing for all students. For this to be more widely accomplished Philosophy in the Classroom and discusses how it constitutes a successful synergy and balance of the troika for effective teaching. It then proposes how it might be embedded into pre-service teacher education.
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In this chapter, a rationale is developed for incorporating philosophy into teacher training programs as a means of both preparing quality teachers for the 21st century and meeting the expectations detailed in the professional standards established by the statutory authority that regulates the profession in Queensland, the Queensland College of Teaching is presented. Furthermore, in-service teachers from Buranda State School, a Brisbane primary school that has been successfully teaching philosophy to its students for over 10 years, shares their experiences of teaching philosophy and how it has enhanced student learning and the quality of teaching and professionalism of the teachers. Finally, the implications of embedding philosophy into teacher training programs are explored in terms of developing the personal integrity of beginning teachers.
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We report that 10% of melanoma tumors and cell lines harbor mutations in the fibroblast growth factor receptor 2 (FGFR2) gene. These novel mutations include three truncating mutations and 20 missense mutations occurring at evolutionary conserved residues in FGFR2 as well as among all four FGFRs. The mutation spectrum is characteristic of those induced by UV radiation. Mapping of these mutations onto the known crystal structures of FGFR2 followed by in vitro and in vivo studies show that these mutations result in receptor loss of function through several distinct mechanisms, including loss of ligand binding affinity, impaired receptor dimerization, destabilization of the extracellular domains, and reduced kinase activity. To our knowledge, this is the first demonstration of loss-of-function mutations in a class IV receptor tyrosine kinase in cancer. Taken into account with our recent discovery of activating FGFR2 mutations in endometrial cancer, we suggest that FGFR2 may join the list of genes that play context-dependent opposing roles in cancer.
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Genitourinary (GU) problems are a common complaint in the community and to the emergency department (ED). Urinary tract infections (UTIs) are the second most common bacterial disease. UTIs rank as the sixteenth most frequently reported problem to general practitioners in Australia1 and between 10% and 20% of women will experience at least one UTI in their lifetime. Over 1,000,000 Australians are currently suffering with nephrolithiasis (renal calculi) and it is hy-pothesised that Australia’s hot, dry climate causes more stone formation than many other coun-tries in the world. Acute kidney injury (AKI) is a common complication of any trauma. Hypovol-aemia results in severe hypotension and this precipitates the development of acute tubular necrosis and subsequent AKI. The incidence of chronic kidney disease (CKD) is rising across the world. CKD is classified into five stages with those in stage 5 being classified as being in end stage kidney disease (ESKD). It is estimated that there are over 1.5 million people in Australia with CKD and there were over 16,000 Australians and over 2900 individuals in New Zealand with ESKD.2 Indigenous populations from both countries (Aboriginals, Torres Strait Islanders, Maoris, and Pacific Islanders) are over-represented in the number of people with all stages of CKD in both countries. Patients with compromised renal function often require the assistance of paramedics and will arrive at the ED with life-threatening fluid and electrolyte imbalances. Spe-cific GU emergencies discussed in this chapter are acute renal failure, rhabdomyolysis, chronic kidney disease, UTIs, acute urinary retention, urinary calculi, testicular torsion, epididymitis, and priapism. Refer to Chapter 31 for discussion of sexually transmitted infections (STIs) in women and to Chapter X for discussion of genitourinary trauma.
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Once melanoma metastasizes, no effective treatment modalities prolong survival in most patients. This notorious refractoriness to therapy challenges investigators to identify agents that overcome melanoma resistance to apoptosis. Whereas many survival pathways contribute to the death-defying phenotype in melanoma, a defect in apoptotic machinery previously highlighted inactivation of Apaf-1, an apoptosome component engaged after mitochondrial damage. During studies involving Notch signaling in melanoma, we observed a gamma-secretase tripeptide inhibitor (GSI; z-Leu-Leu-Nle-CHO), selected from a group of compounds originally used in Alzheimer's disease, induced apoptosis in nine of nine melanoma lines. GSI only induced G2-M growth arrest (but not killing) in five of five normal melanocyte cultures tested. Effective killing of melanoma cells by GSI involved new protein synthesis and a mitochondrial-based pathway mediated by up-regulation of BH3-only members (Bim and NOXA). p53 activation was not necessary for up-regulation of NOXA in melanoma cells. Blocking GSI-induced NOXA using an antisense (but not control) oligonucleotide significantly reduced the apoptotic response. GSI also killed melanoma cell lines with low Apaf-1 levels. We conclude that GSI is highly effective in killing melanoma cells while sparing normal melanocytes. Direct enhancement of BH3-only proteins executes an apoptotic program overcoming resistance of this lethal tumor. Identification of a p53-independent apoptotic pathway in melanoma cells, including cells with low Apaf-1, bypasses an impediment to current cytotoxic therapy and provides new targets for future therapeutic trials involving chemoresistant tumors.
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In recent decades, assessment practices within Australian law schools have moved from the overwhelming use of end-of-year closed-book examinations to an increase in the use of a wider range of techniques. This shift is often characterised as providing a ‘better’ learning environment for students, contributing more positively to their own ‘personal development’ within higher education, or, considered along the lines of critical legal thought, as ‘liberating’ them from the ‘conservatising’ and ‘indoctrinating’ effects of the power relations that operate in law schools. This paper seeks to render problematic such liberal-progressive narratives about these changes to law school assessment practices. It will do so by utilising the work of French historian and philosopher Michel Foucault on power, arguing that the current range of assessment techniques demonstrates a shift in the ‘economy’ of power relations within the law school. Rather than ‘liberating’ students from relations of power, these practices actually extend the power relations through which students are governed. This analysis is intended to inform legal education research and assessment practice by providing a far more nuanced conceptual framework than one that seeks to ‘free’ law students from these ‘repressive’ practices, or hopes to ‘objectively’ contribute to their ‘personal development’.
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This paper examines the use of social enterprise – that is, not for personal profit businesses that have a strong social purpose- to support training and employment pathways for migrants and refugees facing multiple forms of exclusion. Drawing on an evaluation of a program that supports seven social enterprises in the Australian state of Victoria, the study finds that social enterprise affords unique local opportunities for economic and social participation for the program’s participants. Nevertheless, there are limits to the impacts of programs that mediate transitions within an increasingly flexible labour market without redressing the broader social determinants of labour market segmentation.
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Background In Booth v Amaca Pty Ltd and Amaba Pty Ltd,1 the New South Wales Dust Diseases Tribunal awarded a retired motor mechanic $326 640 in damages for his malignant pleural mesothelioma allegedly caused by exposure to asbestos through working with the brake linings manufactured by the defendants. The evidence before the Tribunal was that the plaintiff had been exposed to asbestos prior to working as a mechanic from home renovations when he was a child and loading a truck as a youth. However, as a mechanic he had been exposed to asbestos in brake linings on which he worked from 1953 to 1983. Curtis DCJ held at [172] that the asbestos from the brake linings ‘materially contributed to [the plaintiff’s] contraction of mesothelioma’. This decision was based upon acceptance that the effect of exposure to asbestos on the development of mesothelioma was cumulative and rejection of theory that a single fibre of asbestos can cause the disease...
Resumo:
In an ever changing world the adults of the future will be faced with many challenges. To cope with these challenges it seems apparent that values education will need to become paramount within a child.s education. A considerable number of research studies have indicated that values education is a critical component within education (Lovat & Toomey, 2007b). Building on this research Lovat (2006) claimed that values education was the missing link in quality teaching The concept of quality teaching had risen to the fore within educational research literature in the late 20th century with the claim that it is the teacher who makes the difference in schooling (Hattie, 2004). Thus, if teachers make such a difference to student learning, achievement and well-being, then it must hold true that pre-service teacher education programmes are vital in ensuring the development of quality teachers for our schools. The gap that this current research programme addressed was to link the fields of values education, quality teaching and pre-service teacher education. This research programme aimed to determine the impact of a values-based pedagogy on the development of quality teaching dimensions within pre-service teacher education. The values-based pedagogy that was investigated in this research programme was Philosophy in the Classroom. The research programme adopted a nested case study design based on the constructivist-interpretative paradigm in examining a unit within a pre-service teacher education programme at a Queensland university. The methodology utilised was qualitative where the main source of data was via interviews. In total, 43 pre-service teachers participated in three studies in order to determine if their involvement in a unit where the focus was on introducing pre-service teachers to an explicit values-based pedagogy impacted on their knowledge, skills and confidence in terms of quality teaching dimensions. The research programme was divided into three separate studies in order to address the two research questions: 1. In what ways do pre-service teachers perceive they are being prepared to become quality teachers? 2. Is there a connection between an explicit values-based pedagogy in pre-service teacher education and the development of pre-service teachers. understanding of quality teaching? Study One provided insight into 21 pre-service teachers. understandings of quality teaching. These 21 participants had not engaged in an explicit values-based pedagogy. Study Two involved the interviewing of 22 pre-service teachers at two separate points in time . prior to exposure to a unit that employed a values-explicit pedagogy and post this subject.s lecture content delivery. Study Three reported on and analysed individual case studies of five pre-service teachers who had participated in Study Two Time 1 and Time 2, as well as a third time following their field experience where they had practice in teaching the values explicit pedagogy. The results of the research demonstrate that an explicit values-based pedagogy introduced into a teacher education programme has a positive impact on the development of pre-service teachers. understanding of quality teaching skills and knowledge. The teaching and practice of a values-based pedagogy positively impacted on pre-service teachers with increases of knowledge, skills and confidence demonstrated on the quality teaching dimensions of intellectual quality, a supportive classroom environment, recognition of difference, connectedness and values. These findings were reinforced through the comparison of pre-service teachers who had participated in the explicit values-based pedagogical approach, with a sample of pre-service teachers who had not engaged in this same values-based pedagogical approach. A solid values-based pedagogy and practice can and does enhance pre-service teachers. understanding of quality teaching. These findings surrounding the use of a values-based pedagogy in pre-service teacher education to enhance quality teaching knowledge and skills has contributed theoretically to the field of educational research, as well having practical implications for teacher education institutions and teacher educators.
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This article assesses undergraduate teaching students’ assertion that there are no right and wrong answers in teaching philosophy. When asked questions about their experiences of philosophy in the classroom for primary children, their unanimous declaration that teaching philosophy has ‘no right and wrong answers’ is critically examined across the three sub-disciplinary areas to which they were generally referring, namely, pedagogy, ethics, and epistemology. From a pedagogical point of view, it is argued that some teaching approaches may indeed be more effective than others, and some pupils’ opinions less defensible, but pedagogically, in terms of managing the power relations in the classroom, it is counter-productive to continually insist on notions of truth and falsity at every point. From an ethical point of view, it is contended that anti-realist approaches to meta-ethics may represent a viable intellectual position, but from the point of view of normative ethics, notions of right and wrong still retain significant currency. From an epistemological point of view, it is argued using Karl Poppers’ work that while it may be difficult to determine what constitutes a right answer, determining a wrong one is far more straightforward. In conclusion, it is clear that prospective teachers engaging in philosophy in the classroom, and also future teachers in general, require a far more nuanced philosophical understanding of the notions of right and wrong and truth and falsity. In view of this situation, it we wish to promote the effective teaching of philosophical thinking to children, or produce educators who can understand the conceptual limits of the claims they make and their very real and often serious practical and social consequences, it is recommended that philosophy be reinstated to a fundamental, foundational place within the pre-service teaching curriculum.
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Objective To estimate the incidence and severity of invasive group A streptococcal infection in Victoria, Australia. Design Prospective active surveillance study. Setting Public and private laboratories, hospitals and general practitioners throughout Victoria. Patients eople in Victoria diagnosed with group A streptococcal disease notified to the surveillance system between 1 March 2002 and 31 August 2004. Main outcome measure Confirmed invasive group A streptococcal disease. Results We identified 333 confirmed cases: an average annualised incidence rate of 2.7 (95% CI, 2.3-3.2) per 100000 population per year. Rates were highest in people aged 65 years and older and those younger than 5 years. The case-fatality rate was 7.8%. Streptococcal toxic shock syndrome occurred in 48 patients (14.4%), with a case-fatality rate of 23%. Thirty cases of necrotising fasciitis were reported; five (17%) of these patients died. Type 1 (23%) was the most frequently identified emm sequence type in all, age groups. All tested isolates were susceptible to penicillin and clindamycin. Two isolates (4%) were resistant to erythromycin. Conclusion The incidence of invasive group A streptococcal disease in temperate Australia is greater than previously appreciated and warrants greater public health attention, including its designation as a notifiable disease.
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Ever since sodium fluorescein (‘fluorescein’ [FL]) was first used to investigate the ocular surface over a century ago, the term ‘staining’ has been taken to mean the presence of ocular surface fluorescence [1]. This term has not been necessarily taken to infer any particular mechanism of causation, and indeed, can be attributed to a variety of possible aetiologies [2]. In recent times, there has been considerable interest in a form of ocular surface fluorescence seen in association with the use of certain combinations of soft contact lenses and multipurpose solutions. The first clinical account of this phenomenon was reported by Jones et al. [3], which was followed by a more formal investigation by the same author in 2002 [4]. Jones et al described this appearance as a ‘classic solution-based toxicity reaction’. Subsequently, this appearance has come to be known as ‘solution-induced corneal staining’ or more recently by the acronym ‘SICS’ [5]. The term SICS is potentially problematic in that from a cell biology point of view, there is an inference that ‘staining’ means the entry of a dye into corneal epithelial cells. Morgan and Maldonado-Codina [2] noted there was no foundation of solid scientific literature underpinning our understanding of the true basic causative mechanisms of this phenomenon; since that time, further work has been published in this field [6] and [7] but questions still remain about the precise aetiology of this phenomenon...
Resumo:
Using epistemic perspectives as a theoretical framework, this study investigated Australian pre-service teachers’ perspectives about knowing, knowledge and children’s learning, as they engaged in a semester-long unit on philosophy in the classroom. During the field experience component of the unit, pre-service teachers were required to teach at least one philosophy lesson. Pre-service teachers completed the Personal Epistemological Beliefs Survey at the beginning and end of the unit. They were also interviewed in focus groups at the end of the semester to investigate their views about children’s learning. Paired sample t-tests were used to explore changes in epistemic beliefs over time. Significant differences were found for only some individual items on the survey. However, when interviewed, pre-service teachers indicated that field experiences helped them consider children as competent ‘thinkers’ who were capable of engaging in philosophy in the classroom. They reported predominantly student-centred perspectives of children’s learning, although a process of adjudication (exploring disagreements and evidence for responses) was lacking in these responses.