277 resultados para Pulmonary resistance artery


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In both developed and developing countries, increased prevalence of obesity has been strongly associated with increased incidence of type 2 diabetes mellitus (T2DM) in the adult population. Previous research has emphasized the importance of physical activity in the prevention and management of obesity and T2DM, and generic exercise guidelines originally developed for the wider population have been adapted for these specific populations. However, the guidelines traditionally focus on aerobic training without due consideration to other exercise modalities. Recent reviews on resistance training in the T2DM population have not compared this modality with others including aerobic training, or considered the implications of resistance training for individuals suffering from both obesity and T2DM. In short, the optimal mix of exercise modalities in the prescription of exercise has not been identified for it benefits to the metabolic, body composition and muscular health markers common in obesity and T2DM. Similarly, the underlying physical, social and psychological barriers to adopting and maintaining exercise, with the potential to undermine the efficacy of exercise interventions, have not been addressed in earlier reviews. Because it is well established that aerobic exercise has profound effects on obesity and T2DM risk, the purpose of this review was to address the importance of resistance training to obese adults with T2DM.

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Nontuberculous mycobacteria are ubiquitous environmental organisms that have been recognised as a cause of pulmonary infection for over 50 years. Traditionally patients have had underlying risk factors for development of disease; however the proportion of apparently immunocompetent patients involved appears to be rising. Not all patients culture-positive for mycobacteria will have progressive disease, making the diagnosis difficult, though criteria to aid in this process are available. The two main forms of disease are cavitary disease (usually involving the upper lobes) and fibronodular bronchiectasis (predominantly middle and lingular lobes). For patients with disease, combination antibiotic therapy for 12-24 months is generally required for successful treatment, and this may be accompanied by drug intolerances and side effects. Published success rates range from 30-82%. As the progression of disease is variable, for some patients, attention to pulmonary hygiene and underlying diseases without immediate antimycobacterial therapy may be more appropriate. Surgery can be a useful adjunct, though is associated with risks. Randomised controlled trials in well described patients would provide stronger evidence-based data to guide therapy of NTM lung diseases, and thus are much needed.

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Background: Diets with a high postprandial glycemic response may contribute to long-term development of insulin resistance and diabetes, however previous epidemiological studies are conflicting on whether glycemic index (GI) or glycemic load (GL) are dietary factors associated with the progression. Our objectives were to estimate GI and GL in a group of older women, and evaluate cross-sectional associations with insulin resistance. Subjects and Methods: Subjects were 329 Australian women aged 42-81 years participating in year three of the Longitudinal Assessment of Ageing in Women (LAW). Dietary intakes were assessed by diet history interviews and analysed using a customised GI database. Insulin resistance was defined as a homeostasis model assessment (HOMA) value of >3.99, based on fasting blood glucose and insulin concentrations. Results: GL was significantly higher in the 26 subjects who were classified as insulin resistant compared to subjects who were not (134±33 versus 114±24, P<0.001). In a logistic regression model, an increment of 15 GL units increased the odds of insulin resistance by 2.09 (95%CI 1.55, 2.80, P<0.001) independently of potential confounding variables. No significant associations were found when insulin resistance was assessed as a continuous variable. Conclusions: Results of this cross-sectional study support the concept that diets with a higher GL are associated with increased risk of insulin resistance. Further studies are required to investigate whether reducing glycemic intake, by either consuming lower GI foods and/or smaller serves of carbohydrate, can contribute to a reduction in development of insulin resistance and long-term risk of type 2 diabetes.

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The effects of sintering on several properties of FTO and ITO substates used in DSC have been investigated. FTO & ITO substrates were prepared with a range of sizes and aspect ratios - emulated laboratory style test cells through to prototype modules. Time and temperature of the sintering profiles were varied and sheet resistance and flatness measured. Electrical properties of the substrates were then further characterized by electrochemical impedance spectroscopy, and module sized devices were assembled and thickness variations over the device area were determined and related to performance.

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The call to innovate is ubiquitous across the Australian educational policy context. The claims of innovative practices and environments that occur frequently in university mission statements, strategic plans and marketing literature suggest that this exhortation to innovate appears to have been taken up enthusiastically by the university sector. Throughout the history of universities, a range of reported deficiencies of higher education have worked to produce a notion of crisis. At present, it would seem that innovation is positioned as the solution to the notion of crisis. This thesis is an inquiry into how the insistence on innovation works to both enable and constrain teaching and learning practices in Australian universities. Alongside the interplay between innovation and crisis is the link between resistance and innovation, a link which remains largely unproblematized in the scholarly literature. This thesis works to locate and unsettle understandings of a relationship between innovation and Australian higher education. The aim of this inquiry is to generate new understandings of what counts as innovation within this context and how innovation is enacted. The thesis draws on a number of postmodernist theorists, whose works have informed firstly the research method, and then the analysis and findings. Firstly, there is an assumption that power is capillary and works through discourse to enact power relations which shape certain truths (Foucault, 1990). Secondly, this research scrutinised language practices which frame the capacity for individuals to act, alongside the language practices which encourage an individual to adopt certain attitudes and actions as one’s own (Foucault, 1988). Thirdly, innovation talk is read in this thesis as an example of needs talk, that is, as a medium through which what is considered domestic, political or economic is made and contested (Fraser, 1989). Fourthly, relationships between and within discourses were identified and analysed beyond cause and effect descriptions, and more productively considered to be in a constant state of becoming (Deleuze, 1987). Finally, the use of ironic research methods assisted in producing alternate configurations of innovation talk which are useful and new (Rorty, 1989). The theoretical assumptions which underpin this thesis inform a document analysis methodology, used to examine how certain texts work to shape the ways in which innovation is constructed. The data consisted of three Federal higher education funding policies selected on the rationale that these documents, as opposed to state or locally based policy and legislation, represent the only shared policy context for all Australian universities. The analysis first provided a modernist reading of the three documents, and this was followed by postmodernist readings of these same policy documents. The modernist reading worked to locate and describe the current truths about innovation. The historical context in which the policy was produced as well as the textual features of the document itself were important to this reading. In the first modernist reading, the binaries involved in producing proper and improper notions of innovation were described and analysed. In the process of the modernist analysis and the subsequent location of binary organisation, a number of conceptual collisions were identified, and these sites of struggle were revisited, through the application of a postmodernist reading. By applying the theories of Rorty (1989) and Fraser (1989) it became possible to not treat these sites as contradictory and requiring resolution, but rather as spaces in which binary tensions are necessary and productive. This postmodernist reading constructed new spaces for refusing and resisting dominant discourses of innovation which value only certain kinds of teaching and learning practices. By exploring a number of ironic language practices found within the policies, this thesis proposes an alternative way of thinking about what counts as innovation and how it happens. The new readings of innovation made possible through the work of this thesis were in response to a suite of enduring, inter-related questions – what counts as innovation?, who or what supports innovation?, how does innovation occur?, and who are the innovators?. The truths presented in response to these questions were treated as the language practices which constitute a dominant discourse of innovation talk. The collisions that occur within these truths were the contested sites which were of most interest for the analysis. The thesis concludes by presenting a theoretical blueprint which works to shift the boundaries of what counts as innovation and how it happens in a manner which is productive, inclusive and powerful. This blueprint forms the foundation upon which a number of recommendations are made for both my own professional practice and broader contexts. In keeping with the conceptual tone of this study, these recommendations are a suite of new questions which focus attention on the boundaries of innovation talk as an attempt to re-configure what is valued about teaching and learning at university.

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The high morbidity and mortality associated with atherosclerotic coronary vascular disease (CVD) and its complications are being lessened by the increased knowledge of risk factors, effective preventative measures and proven therapeutic interventions. However, significant CVD morbidity remains and sudden cardiac death continues to be a presenting feature for some subsequently diagnosed with CVD. Coronary vascular disease is also the leading cause of anaesthesia related complications. Stress electrocardiography/exercise testing is predictive of 10 year risk of CVD events and the cardiovascular variables used to score this test are monitored peri-operatively. Similar physiological time-series datasets are being subjected to data mining methods for the prediction of medical diagnoses and outcomes. This study aims to find predictors of CVD using anaesthesia time-series data and patient risk factor data. Several pre-processing and predictive data mining methods are applied to this data. Physiological time-series data related to anaesthetic procedures are subjected to pre-processing methods for removal of outliers, calculation of moving averages as well as data summarisation and data abstraction methods. Feature selection methods of both wrapper and filter types are applied to derived physiological time-series variable sets alone and to the same variables combined with risk factor variables. The ability of these methods to identify subsets of highly correlated but non-redundant variables is assessed. The major dataset is derived from the entire anaesthesia population and subsets of this population are considered to be at increased anaesthesia risk based on their need for more intensive monitoring (invasive haemodynamic monitoring and additional ECG leads). Because of the unbalanced class distribution in the data, majority class under-sampling and Kappa statistic together with misclassification rate and area under the ROC curve (AUC) are used for evaluation of models generated using different prediction algorithms. The performance based on models derived from feature reduced datasets reveal the filter method, Cfs subset evaluation, to be most consistently effective although Consistency derived subsets tended to slightly increased accuracy but markedly increased complexity. The use of misclassification rate (MR) for model performance evaluation is influenced by class distribution. This could be eliminated by consideration of the AUC or Kappa statistic as well by evaluation of subsets with under-sampled majority class. The noise and outlier removal pre-processing methods produced models with MR ranging from 10.69 to 12.62 with the lowest value being for data from which both outliers and noise were removed (MR 10.69). For the raw time-series dataset, MR is 12.34. Feature selection results in reduction in MR to 9.8 to 10.16 with time segmented summary data (dataset F) MR being 9.8 and raw time-series summary data (dataset A) being 9.92. However, for all time-series only based datasets, the complexity is high. For most pre-processing methods, Cfs could identify a subset of correlated and non-redundant variables from the time-series alone datasets but models derived from these subsets are of one leaf only. MR values are consistent with class distribution in the subset folds evaluated in the n-cross validation method. For models based on Cfs selected time-series derived and risk factor (RF) variables, the MR ranges from 8.83 to 10.36 with dataset RF_A (raw time-series data and RF) being 8.85 and dataset RF_F (time segmented time-series variables and RF) being 9.09. The models based on counts of outliers and counts of data points outside normal range (Dataset RF_E) and derived variables based on time series transformed using Symbolic Aggregate Approximation (SAX) with associated time-series pattern cluster membership (Dataset RF_ G) perform the least well with MR of 10.25 and 10.36 respectively. For coronary vascular disease prediction, nearest neighbour (NNge) and the support vector machine based method, SMO, have the highest MR of 10.1 and 10.28 while logistic regression (LR) and the decision tree (DT) method, J48, have MR of 8.85 and 9.0 respectively. DT rules are most comprehensible and clinically relevant. The predictive accuracy increase achieved by addition of risk factor variables to time-series variable based models is significant. The addition of time-series derived variables to models based on risk factor variables alone is associated with a trend to improved performance. Data mining of feature reduced, anaesthesia time-series variables together with risk factor variables can produce compact and moderately accurate models able to predict coronary vascular disease. Decision tree analysis of time-series data combined with risk factor variables yields rules which are more accurate than models based on time-series data alone. The limited additional value provided by electrocardiographic variables when compared to use of risk factors alone is similar to recent suggestions that exercise electrocardiography (exECG) under standardised conditions has limited additional diagnostic value over risk factor analysis and symptom pattern. The effect of the pre-processing used in this study had limited effect when time-series variables and risk factor variables are used as model input. In the absence of risk factor input, the use of time-series variables after outlier removal and time series variables based on physiological variable values’ being outside the accepted normal range is associated with some improvement in model performance.

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One approach to reducing the yield losses caused by banana viral diseases is the use of genetic engineering and pathogen-derived resistance strategies to generate resistant cultivars. The development of transgenic virus resistance requires an efficient banana transformation method, particularly for commercially important 'Cavendish' type cultivars such as 'Grand Nain'. Prior to this study, only two examples of the stable transformation of banana had been reported, both of which demonstrated the principle of transformation but did not characterise transgenic plants in terms of the efficiency at which individual transgenic lines were generated, relative activities of promoters in stably transformed plants, and the stability of transgene expression. The aim of this study was to develop more efficient transformation methods for banana, assess the activity of some commonly used and also novel promoters in stably transformed plants, and transform banana with genes that could potentially confer resistance to banana bunchy top nanovirus (BBTV) and banana bract mosaic potyvirus (BBrMV). A regeneration system using immature male flowers as the explant was established. The frequency of somatic embryogenesis in male flower explants was influenced by the season in which the inflorescences were harvested. Further, the media requirements of various banana cultivars in respect to the 2,4-D concentration in the initiation media also differed. Following the optimisation of these and other parameters, embryogenic cell suspensions of several banana (Musa spp.) cultivars including 'Grand Nain' (AAA), 'Williams' (AAA), 'SH-3362' (AA), 'Goldfinger' (AAAB) and 'Bluggoe' (ABB) were successfully generated. Highly efficient transformation methods were developed for both 'Bluggoe' and 'Grand Nain'; this is the first report of microprojectile bombardment transformation of the commercially important 'Grand Nain' cultivar. Following bombardment of embryogenic suspension cells, regeneration was monitored from single transfom1ed cells to whole plants using a reporter gene encoding the green fluorescent protein (gfp). Selection with kanamycin enabled the regeneration of a greater number of plants than with geneticin, while still preventing the regeneration of non-transformed plants. Southern hybridisation confirmed the neomycin phosphotransferase gene (npt II) was stably integrated into the banana genome and that multiple transgenic lines were derived from single bombardments. The activity, stability and tissue specificity of the cauliflower mosaic virus 358 (CaMV 35S) and maize polyubiquitin-1 (Ubi-1) promoters were examined. In stably transformed banana, the Ubi-1 promoter provided approximately six-fold higher p-glucuronidase (GUS) activity than the CaMV 35S promoter, and both promoters remained active in glasshouse grown plants for the six months they were observed. The intergenic regions ofBBTV DNA-I to -6 were isolated and fused to either the uidA (GUS) or gfjJ reporter genes to assess their promoter activities. BBTV promoter activity was detected in banana embryogenic cells using the gfp reporter gene. Promoters derived from BBTV DNA-4 and -5 generated the highest levels of transient activity, which were greater than that generated by the maize Ubi-1 promoter. In transgenic banana plants, the activity of the BBTV DNA-6 promoter (BT6.1) was restricted to the phloem of leaves and roots, stomata and root meristems. The activity of the BT6.1 promoter was enhanced by the inclusion of intron-containing fragments derived from the maize Ubi-1, rice Act-1, and sugarcane rbcS 5' untranslated regions in GUS reporter gene constructs. In transient assays in banana, the rice Act-1 and maize Ubi-1 introns provided the most significant enhancement, increasing expression levels 300-fold and 100-fold, respectively. The sugarcane rbcS intron increased expression about 10-fold. In stably transformed banana plants, the maize Ubi-1 intron enhanced BT6.1 promoter activity to levels similar to that of the CaMV 35S promoter, but did not appear to alter the tissue specificity of the promoter. Both 'Grand Nain' and 'Bluggoe' were transformed with constructs that could potentially confer resistance to BBTV and BBrMV, including constructs containing BBTV DNA-1 major and internal genes, BBTV DNA-5 gene, and the BBrMV coat protein-coding region all under the control of the Ubi-1 promoter, while the BT6 promoter was used to drive the npt II selectable marker gene. At least 30 transgenic lines containing each construct were identified and replicates of each line are currently being generated by micropropagation in preparation for virus challenge.