983 resultados para 147-894
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In this paper, we consider a time-space fractional diffusion equation of distributed order (TSFDEDO). The TSFDEDO is obtained from the standard advection-dispersion equation by replacing the first-order time derivative by the Caputo fractional derivative of order α∈(0,1], the first-order and second-order space derivatives by the Riesz fractional derivatives of orders β 1∈(0,1) and β 2∈(1,2], respectively. We derive the fundamental solution for the TSFDEDO with an initial condition (TSFDEDO-IC). The fundamental solution can be interpreted as a spatial probability density function evolving in time. We also investigate a discrete random walk model based on an explicit finite difference approximation for the TSFDEDO-IC.
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Background: Polybrominated diphenyl ethers (PBDEs) are used as flame retardants in many products and have been detected in human samples worldwide. Limited data show that concentrations are elevated in young children. Objectives: We investigated the association between PBDEs and age with an emphasis on young children from Australia in 2006–2007. Methods: We collected human blood serum samples (n = 2,420), which we stratified by age and sex and pooled for analysis of PBDEs. Results: The sum of BDE-47, -99, -100, and -153 concentrations (Σ4PBDE) increased from 0–0.5 years (mean ± SD, 14 ± 3.4 ng/g lipid) to peak at 2.6–3 years (51 ± 36 ng/g lipid; p < 0.001) and then decreased until 31–45 years (9.9 ± 1.6 ng/g lipid). We observed no further significant decrease among ages 31–45, 45–60 (p = 0.964), or > 60 years (p = 0.894). The mean Σ4PBDE concentration in cord blood (24 ± 14 ng/g lipid) did not differ significantly from that in adult serum at ages 15–30 (p = 0.198) or 31–45 years (p = 0.140). We found no temporal trend when we compared the present results with Australian PBDE data from 2002–2005. PBDE concentrations were higher in males than in females; however, this difference reached statistical significance only for BDE-153 (p = 0.05). Conclusions: The observed peak concentration at 2.6–3 years of age is later than the period when breast-feeding is typically ceased. This suggests that in addition to the exposure via human milk, young children have higher exposure to these chemicals and/or a lower capacity to eliminate them. Key words: Australia, children, cord blood, human blood serum, PBDEs, polybrominated diphenyl ethers. Environ Health Perspect 117:1461–1465 (2009). doi:10.1289/ehp.0900596
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The effectiveness of using thermally activated hydrotalcite materials has been investigated for the removal of arsenate, vanadate, and molybdate in individual and mixed solutions. Results show that increasing the Mg,Al ratio to 4:1 causes an increase in the percentage of anions removed from solution. The order of affinity of the three anions analysed in this investigation is arsenate, vanadate, and molybdate. By comparisons with several synthetic hydrotalcite materials, the hydrotalcite structure in the seawater neutralised red mud (SWN-RM) has been determined to consist of magnesium and aluminium with a ratio between 3.5:1 and 4:1. Thermally activated seawater neutralised red mud removes at least twice the concentration of anionic species than thermally activated red mud alone, due to the formation of 40 to 60 % Bayer hydrotalcite during the neutralisation process.
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The industrial application of kaolinite is closely related to its reactivity and surface properties. The reactivity of kaolinite can be tested by intercalation, i.e. via the insertion of low molecular weight organic compounds between the kaolinite layers resulting in the formation of a nano-layered organo-complex. Although intercalation of kaolinite is an old and ongoing research topic, there is a limited knowledge available on the reactivity of different kaolinites, the mechanism of complex formation as well as on the structure of the complexes formed. Grafting and incorporation of exfoliated kaolinite in polymer matrices and other potential applications can open new horizons in the study of kaolinite intercalation. This paper attempts to summarize (without completion) the most recent achievements in the study of kaolinite organo-complexes obtained with the most common intercalating compounds like urea, potassium acetate, dimethyl sulphoxide, formamide and hydrazine using vibrational spectroscopy combined with X-ray powder diffraction and thermal analysis.
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This special issue of Innovation : Management, Policy & Practice (also released as a book: ISBN 978-1-921348-31-0) will explore some empirical and analytic connections between creative industries and innovation policy. Seven papers are presented. The first four are empirical, providing analysis of large and/or detailed data sets on creative industries businesses and occupations to discern their contribution to innovation. The next three papers focus on comparative and historical policy analysis, connecting creative industries policy (broadly considered, including media, arts and cultural policy) and innovation policy. To introduce this special issue I want to review the arguments connecting the statistical, conceptual and policy neologism of ‘creative industries’ to: (1) the elements of a national innovation system; and (2) to innovation policy. In approaching this connection, two overarching issues arise.
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Pedestrian and cyclist injuries are significant public health issues together accounting for 11-30% of road deaths in highly motorised countries. Children are particularly at risk. In Australia in 2009 children 0-16 years comprised 11.4% of pedestrian deaths and 6.4% of cyclist deaths. Parental attitudes and level of supervision are important to children’s road safety. Results from a telephone survey with parents of children 5-9 years (N=147) are reported. Questions addressed beliefs about preventability of injury, appropriate ages for children to cross the road or cycle independently, and the frequency of holding 5-9 year old children’s hands while crossing the road. Results suggest that parents believe most injuries are preventable and that they personally can act to improve their own safety in the home, on the road, at work, as well as in or on the water. Most parents (68%) indicated children should be 10 years or older before crossing the road or cycling independently. Parents were more likely to report holding younger children’s hands (5-6 years) when crossing the road and less likely to do so for 7-9 year olds. There was a small effect of child gender, with parents more likely to hold boy’s hand than a girl’s.
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This paper, underpinned by a framework of autopoietic principles of creativity/innovation and leadership/governance, argues that open forms of creativity in ‘arts’ provide opportunity for impact upon concepts of development, leadership and governance. The alliance of creativity and governance suggests that by examining various understandings of artistic experiences, readers may perceive new understandings of alliance, application and assessment of such experiences. This critical understanding would include assessing whether such experience supports people changing their aspirations as they become what they want to be. Such understanding may also suggest that different applications of the creative capacity of the ‘arts’ offers relevance in alleged ‘non-creative’ areas of academe, particularly in areas of management, leadership and governance. This alliance also offers the possibility of new staff development programs that facilitate learning and building of individual capacity, as well as facilitate congruent development process and policy, particularly within academic organisational structures.
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The Government of the Hong Kong SAR sponsored a report investigating the Hong Kong construction inudstry and published the investigating committee's findings in 2001 (HK CIRC 2001). Since then the Provisional Construction Industry Coordination Board (PCICB), and its successor, the Construction Industry Council (CIC), also set up by the Government, has made progress with the necessary reforms. Now that seven years have passed, it is time for an independent evaluation of the impact of the CIRC initiative in order to assist the CIC and the Government decision-makers in refining the efforts to improve the industry's performance. This paper reports on the interim results of a study that seeks to provide such an evaluation.
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This chapter deals with the law concerning children and consent to medical treatment. Where a child under the age of 18 requires medical treatment, issues arise as to who may lawfully consent to the treatment and under what circumstances. Depending on the circumstances, consent may be given by the child’s parent or guardian; the child; or a court. The chapter provides a thorough treatment of Australian law about these issues and circumstances.
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OBJECTIVE To examine the psychometric properties of a Chinese version of the Problem Areas In Diabetes (PAID-C) scale. RESEARCH DESIGN AND METHODS The reliability and validity of the PAID-C were evaluated in a convenience sample of 205 outpatients with type 2 diabetes. Confirmatory factor analysis, Bland-Altman analysis, and Spearman's correlations facilitated the psychometric evaluation. RESULTS Confirmatory factor analysis confirmed a one-factor structure of the PAID-C (χ2/df ratio = 1.894, goodness-of-fit index = 0.901, comparative fit index = 0.905, root mean square error of approximation = 0.066). The PAID-C was associated with A1C (rs = 0.15; P < 0.05) and diabetes self-care behaviors in general diet (rs = −0.17; P < 0.05) and exercise (rs = −0.17; P < 0.05). The 4-week test-retest reliability demonstrated satisfactory stability (rs = 0.83; P < 0.01). CONCLUSIONS The PAID-C is a reliable and valid measure to determine diabetes-related emotional distress in Chinese people with type 2 diabetes.
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Recently discovered intrinsically photosensitive melanopsin retinal ganglion cells contribute to the maintenance of pupil diameter, recovery and post-illumination components of the pupillary light reflex and provide the primary environmental light input to the suprachiasmatic nucleus for photoentrainment of the circadian rhythm. This review summarises recent progress in understanding intrinsically photosensitive ganglion cell histology and physiological properties in the context of their contribution to the pupillary and circadian functions and introduces a clinical framework for using the pupillary light reflex to evaluate inner retinal (intrinsically photosensitive melanopsin ganglion cell) and outer retinal (rod and cone photoreceptor) function in the detection of retinal eye disease.
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Understanding the impacts of traffic and climate change on water quality helps decision makers to develop better policy and plans for dealing with unsustainable urban and transport development. This chapter presents detailed methodologies developed for sample collection and testing for heavy metals and total petroleum hydrocarbons, as part of a research study to investigate the impacts of climate change and changes to urban traffic characteristics on pollutant build-up and wash-off from urban road surfaces. Cadmium, chromium, nickel, copper, lead, iron, aluminium, manganese and zinc were the target heavy metals, and selected gasoline and diesel range organics were the target total petroleum hydrocarbons for this study. The study sites were selected to encompass the urban traffic characteristics of the Gold Coast region, Australia. An improved sample collection method referred to as ‘the wet and dry vacuum system’ for the pollutant build-up, and an effective wash-off plan to incorporate predicted changes to rainfall characteristics due to climate change, were implemented. The novel approach to sample collection for pollutant build-up helped to maintain the integrity of collection efficiency. The wash-off plan helped to incorporate the predicted impacts of climate change in the Gold Coast region. The robust experimental methods developed will help in field sample collection and chemical testing of different stormwater pollutants in build-up and wash-off.