993 resultados para 7137-141


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Interactions of chemicals with the microtubular network of cells may lead to genotoxicity. Micronuclei (MN) might be caused by interaction of metals with tubulin and/or kinesin. The genotoxic effects of inorganic lead and mercury salts were studied using the MN assay and the CREST analysis in V79 Chinese hamster fibroblasts. Effects on the functional activity of motor protein systems were examined by measurement of tubulin assembly and kinesin-driven motility. Lead and mercury salts induced MN dose-dependently. The no-effect-concentration for MN induction was 1.1 μM PbCl2, 0.05 μM Pb(OAc)2 and 0.01 μM HgCl2. The in vitro results obtained for PbCl2 correspond to reported MN induction in workers occupationally exposed to lead, starting at 1.2 μM Hg(II) (Vaglenov et al., 2001, Environ. Health Perspect. 109, 295-298). The CREST Analysis indicate aneugenic effects of Pb(II) and aneugenic and additionally clastogenic effects of Hg(II). Lead (chloride, acetate, and nitrate) and mercury (chloride and nitrate) interfered dose-dependently with tubulin assembly in vitro. The no-effect-concentration for lead salts in this assay was 10 μM. Inhibition of tubulin assembly by mercury started at 2 μM. The gliding velocity of microtubules along immobilised kinesin molecules was affected by 25 μM Pb(NO3)2 and 0.1 μM HgCl2 in a dose-dependent manner. Our data support the hypothesis that lead and mercury genotoxicity may result, at least in part, via disturbance of chromosome segregation via interaction with cytoskeletal proteins.

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Objective Migraine is a highly disabling disease affecting a significant proportion of the Australian population. The Methylenetetrahydrofolate Reductase (MTHFR) C677T variant has been associated with increased levels of homocysteine and risk of migraine with aura (MA). Folic acid, Vitamin B6 and B12 supplementation has been previously shown to reduce increased levels of homocysteine and decrease migraine symptoms. However the influence of dietary folate intake on migraine has been unclear. The aim of the current study was to analyse the association of dietary folate intake in the form of dietary folate equivalent (DFE), folic acid (FA) and total food folate (TFF) on migraine frequency, severity and disability. Methods A cohort of 141 adult females of Caucasian descent with MA was genotyped for the MTHFRC677T variant using restriction enzyme digestion. Dietary folate information was collected from all participants and analysed using the “FoodWorks” 2009 package. Folate consumption was compared to migraine frequency, severity and disability using linear regression. Results A significant inverse relation was observed between DFE [R2= 0.201, P= 0.045, CI (-0.004, -0.001)] and FA [R2= 0.255, P= 0.036, 95% CI (-0.009, -0.002)] consumption and migraine frequency. It was also observed that in individuals with the CC genotype for the MTHFR C677T variant, migraine frequency was significantly linked to FA consumption [R2= 0.077, P= 0.029, CI (-0.009, -0.005)]. Conclusions The results from this study indicate that folate intake in the form of folic acid may influence migraine frequency in female MA sufferers.

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Housing affordability and sustainable development are not polarised ideologies as both are necessary with increasing urbanisation. We must bridge the gap between current median house pricing and target affordable house pricing whilst pursuing sustainability. This paper examines the potential of initial construction cost and ongoing utilities and transport cost reduction through the integration of sustainable housing design and transit oriented development principles in a Commuter Energy and Building Utilities System (CEBUS). It also introduces current research on the development of a Dynamic Simulation Model for CEBUS applications in the Australian property development and construction industry.

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This chapter reviews spontaneous volunteering in Australia and its challenges for volunteers and volunteer organisations. Drawing on their own empirical research mzd the wider literature, the authors suggest that better understanding of the nature and functions of spontaneous volunteering is needed to support community resilience and individual wellbeing.

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Picture books are known and familiar objects to many children and adults. They have been variously described as art objects, cultural documents, hybrid texts and verbal-visual art forms. They have also been variously categorised according to their readership – ranging from very young children to older readers, the latter can extend through the primary years to high school and even into adulthood. Scholars and students study picture books as part of an evolving literary and cultural landscape which has given rise to new genres and trends, such as ‘multicultural picture books’, ‘environmental picture books’ and ‘postmodern picture books’, and what Cherie Allan terms, ‘postmodernesque picture books’, that is, ‘picturebooks about postmodernity’ (Allan, 2012, p. 141). Picture books are also the staple literature in many early years and primary school classrooms for literacy and literary development, thus supporting the designated strands for literacy, literature, and language in the Australian Curriculum: English.

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Increasing population pressures and life-style choices are resulting in more people living in areas that are at risk of inundation from rising sea levels and flooding. However, following natural disaster events, such as the 2011 Queensland floods, many Australians discovered they were uninsured. Either their insurance policies did not cover flood; or multiple (and confusing) water-related definitions led them to believe they had cover when they did not. Several theories are analysed to try to explain what is a world-wide underinsurance problem but these do not provide an answer to the problem. This research focuses on uncovering the reasons consumers fail to adequately insure for flood and other water-related events. Recent Australian legislative attempts to overcome insureds’ confusion of water related definitions are examined for this purpose. The authors conclude that Australian and other) legislators should set a maximum premium for a minimum amount of flood and sea related cover; and restrict the building and style of homes in flood prone areas.

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An automated melanoma diagnosis system, the so-called Skin Polar-probe, was developed to improve the chances of early detection of skin cancers and help save the lives of melanoma victims. The system will offer unique benefits to aid early detection of melanoma - the key to reducing deaths caused by this cancer.

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Background: Recently, we found a telephone-delivered secondary prevention programme using health coaching (‘ProActive Heart’) to be effective in improving a range of key behavioural outcomes for myocardial infarction (MI) patients. What remains unclear, however, is the extent to which these treatment effects translate to important psychological outcomes such as depression and anxiety outcomes, an issue of clinical significance due to the substantial proportion of MI patients who experience depression and anxiety. The objective of the study was to investigate, as a secondary hypothesis of a larger trial, the effects of a telephone-delivered health coaching programme on depression and anxiety outcomes of MI patients. Design: Two-arm, parallel-group, randomized, controlled design with six-months outcomes. Methods: Patients admitted to one of two tertiary hospitals in Brisbane, Australia following MI were assessed for eligibility. Four hundred and thirty patients were recruited and randomly assigned to usual care or an intervention group comprising up to 10 telephone-delivered ‘health coaching’ sessions (ProActive Heart). Regression analysis compared Hospital Anxiety and Depression Scale scores of completing participants at six months (intervention: n = 141 versus usual care: n = 156). Results: The intervention yielded reductions in anxiety at follow-up (mean difference = −0.7, 95% confidence interval=−1.4,−0.02) compared with usual care. A similar pattern was observed in mean depression scores but was not statistically significant. Conclusions: The ProActive Heart programme effectively improves anxiety outcomes of patients following myocardial infarction. If combined with psychological-specific treatment, this programme could impact anxiety of greater intensity in a clinically meaningful way.

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Is there a threshold above which hand-rub solution consumption is efficient for decreasing MRSA incidence? [J Hosp Infect. 2009] Association between an index of consumption of hand-rub solution and the incidence of acquired meticillin-resistant Staphylococcus aureus in an intensive care unit.

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In this chapter we describe and explain the ways we negotiated these same epistemological tensions and structural realities as we implemented the iPad loan component of the project reported in this book (hereafter: “iPad loan program”).Children who participated in the iPad loan program were able to take home one of the project iPads used in their preschool centre, much as they were able to take home books and puzzles. This component was one reflection of the ethos of “digital inclusion” that infused the project. As we noted in the introduction to this book, there is international recognition of the role that schools can play in ensuring all communities can participate in digital culture and the digital economy (e.g., European Commission, 2014; United States Government, 2013). Accordingly, we conducted the project in preschool centres where at least some groups of children were thought to enjoy less access to learning on digital platforms than others. Our goal was to put the iPad into the hands of children who might not otherwise have had access to it, while supporting teachers and parents in capitalising on the learning potential of the device for all the children. Centres nominated for the project by administrators in the preschool system all served communities that were either affected by poverty and/or diverse in language and culture.

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Distance education has gone through rapid expansion over the years. Many Australian universities are pushing the use of distance education in delivering construction education programs. However, the critical success factors (CSFs) in distance learning construction programs (DLCPs) are not fully understood. More importantly, students’ demographic features may affect the selection of distance education technologies. Situation-matching strategies should therefore be taken by universities or institutions with different student cohorts. A survey is adopted in Central Queensland University (CQU) to identify and rank the critical success factors in a DLCP in Australia where there is a significant number of earner-learners and students with low socioeconomic background. The findings suggest that the most important CSFs include access to computers and internet, reliability of web-based learning sites, high relevance and clarity of learning materials and assessment items, the availability of web-based learning sites that can be easily manipulated, and the capability of the instructors to provide well-structured courses. The findings also suggest that students with low socioeconomic background have more rigorous requirements on interface design, instructors’ support, and the integration of practical components into courses. The results provide good guidance of the design and delivery of DLCPs and will be useful for universities and institutions that are seeking to implement the distance mode in construction education.

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This paper relates to the importance of impact of the chosen bottle-point method when conducting ion exchange equilibria experiments. As an illustration, potassium ion exchange with strong acid cation resin was investigated due to its relevance to the treatment of various industrial effluents and groundwater. The “constant mass” bottle-point method was shown to be problematic in that depending upon the resin mass used the equilibrium isotherm profiles were different. Indeed, application of common equilibrium isotherm models revealed that the optimal fit could be with either the Freundlich or Temkin equations, depending upon the conditions employed. It could be inferred that the resin surface was heterogeneous in character, but precise conclusions regarding the variation in the heat of sorption were not possible. Estimation of the maximum potassium loading was also inconsistent when employing the “constant mass” method. The “constant concentration” bottle-point method illustrated that the Freundlich model was a good representation of the exchange process. The isotherms recorded were relatively consistent when compared to the “constant mass” approach. Unification of all the equilibrium isotherm data acquired was achieved by use of the Langmuir Vageler expression. The maximum loading of potassium ions was predicted to be at least 116.5 g/kg resin.