83 resultados para 405


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A contract to buy or sell a home is the most important contract most people will ever make. It is crucial that the purchase or sale is made carefully and correctly. Similarly, maintaining a home and undertaking repairs or renovations can be significant aspects of life. This chapter will explore these issues under the broad headings of: • buying a home • selling a home • building or renovating a home.

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Background A population-based, cross-sectional telephone survey was conducted to estimate the penetrance and characteristics of contact lens wear in Australia. Methods Based on postcode distribution, 42,749 households around Australia were randomly selected from the national electronic telephone directory. During calls, the number of individuals and contact lens wearers in each household aged between 15 and 64 years was ascertained. Contact lens wearers were interviewed using a structured questionnaire, to determine details of demographics, lens type, mode of lens wear and hygienic habits. Contact lens wear characteristics and habits were compared by lens type and mode of use. Results Of the 32,405 households contacted, 19,171 (59.2 per cent) agreed to participate. The penetrance of contact lens wear during the study period was 5.01 per cent (95% CI: 4.78-5.24). The mean age of lens wearers was 36.5 ± 18.3 years and 63.4 per cent were female. There were significant differences in the habits and characteristics of lens wearers depending on their lens type and mode of use. Conclusions The penetrance of contact lens wear concurs with market estimates and equates to approximately 680,000 contact lens wearers aged between 15 and 64 years in Australia. This is the most detailed and extensive population-based survey of contact lens wearers ever conducted. The discrepancies found between the characteristics of lens wearers surveyed in this study compared to those in previous studies of contact lens practitioners highlights the importance of study design. These results may be applied to other regions with similar health-care and regulatory systems.

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The discovery by Watson and Crick of the structure of DNA is one of the great scientific discoveries. In the period since that discovery new areas of genetic research have opened up which hold out the hope of developing treatments or cures for many illnesses and diseases. Yet with these discoveries have also come an array of ethical and legal dilemmas about the use of genetic information and concerns about the potential for those with genetic diseases or conditions to be stigmatised and discriminated against. The discussion about the developments in genetic science has become increasingly, a debate about the use of genetic information within our society. Graeme Laurie’s book, Genetic Privacy: A Challenge to Medico-Legal Norms, guides the reader through the complexities of these debates by considering what we mean by privacy and asking whether our existing concepts are adequate to meet the challenges posed by the new genetics.

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Increasing role of electronic health care in Australia - possibilities of e-health in terms of provider-to-consumer initiatives and of business-to-business initiatives - challenges of e-health in the context of existing laws and recent reforms - assessment of the adequacy of existing laws to meet the challenges posed by e-health

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In this paper, we address the control design problem of positioning of over-actuated underwater vehicles. The proposed design is based on a control architecture with combined position and velocity loops and a control tuning method based on the decoupled models. We derive analytical tuning rules based on requirements of closed-loop stability, positioning performance, and the vehicle velocity dynamic characteristics. The vehicle modelling is considered from force to motion with appropriate simplifications related to low-speed manoeuvring hydrodynamics and vehicle symmetry. The control design is considered together with a control allocation mapping. This approach makes the control tuning independent of the characteristics of the force actuators and provides the basis for control reconfiguration in the presence of actuator failure. We propose an anti-wind-up implementation of the controller, which ensures that the constraints related to actuation capacity are not violated. This approach simplifies the control allocation problem since the actuator constraints are mapped into generalised force constraints.

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Twitter is a social media service that has managed very successfully to embed itself deeply in the daily lives of its users. Its short message length (140 characters), and one-way connections (‘following’ rather than ‘friending’), lead themselves effectively to random and regular updates on almost any form of personal or professional activity. Thus, it has found uses from the interpersonal (e.g. Boyd et al., 2010) through crisis communication (e.g. Bruns et al., 2012), to political debate (e.g. Burgess & Bruns, 2012). In such uses, Twitter does not necessarily replace existing media channels, such as broadcasting or online mainstream media, but often complements them, providing its users with alternative opportunities to contribute more actively to the wider media sphere. This is true especially where Twitter is used alongside television, as a simple backchannel to live programming or for more sophisticated uses. In this article, we outline four aspects and dimensions, of the way that the old medium of television intersects, and in some cases, interacts with the new medium of Twitter. Tweeting about the television has always been a social media form. It has also consistently provided key ‘talking points’ for western societies...

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This paper demonstrates the use of a spreadsheet in exploring non-linear difference equations that describe digital control systems used in radio engineering, communication and computer architecture. These systems, being the focus of intensive studies of mathematicians and engineers over the last 40 years, may exhibit extremely complicated behaviour interpreted in contemporary terms as transition from global asymptotic stability to chaos through period-doubling bifurcations. The authors argue that embedding advanced mathematical ideas in the technological tool enables one to introduce fundamentals of discrete control systems in tertiary curricula without learners having to deal with complex machinery that rigorous mathematical methods of investigation require. In particular, in the appropriately designed spreadsheet environment, one can effectively visualize a qualitative difference in the behviour of systems with different types of non-linear characteristic.

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This paper examines the properties of various approximation methods for solving stochastic dynamic programs in structural estimation problems. The problem addressed is evaluating the expected value of the maximum of available choices. The paper shows that approximating this by the maximum of expected values frequently has poor properties. It also shows that choosing a convenient distributional assumptions for the errors and then solving exactly conditional on the distributional assumption leads to small approximation errors even if the distribution is misspecified. © 1997 Cambridge University Press.

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The mineral kidwellite, a hydrated hydroxy phosphate of ferric iron and sodium of approximate formula NaFe93+(PO4)6(OH)11⋅3H2O, has been studied using a combination of electron microscopy with EDX and vibrational spectroscopic techniques. Raman spectroscopy identifies an intense band at 978 cm−1 and 1014 cm−1. These bands are attributed to the PO43− ν1 symmetric stretching mode. The ν3 antisymmetric stretching modes are observed by a large number of Raman bands. The series of Raman bands at 1034, 1050, 1063, 1082, 1129, 1144 and 1188 cm−1 are attributed to the ν3 antisymmetric stretching bands of the PO43− and HOPO32− units. The observation of these multiple Raman bands in the symmetric and antisymmetric stretching region gives credence to the concept that both phosphate and hydrogen phosphate units exist in the structure of kidwellite. The series of Raman bands at 557, 570, 588, 602, 631, 644 and 653 cm−1are assigned to the PO43− ν2 bending modes. The series of Raman bands at 405, 444, 453, 467, 490 and 500 cm−1 are attributed to the PO43− and HOPO32− ν4 bending modes. The spectrum is quite broad but Raman bands may be resolved at 3122, 3231, 3356, 3466 and 3580 cm−1. These bands are assigned to water stretching vibrational modes. The number and position of these bands suggests that water is in different molecular environments with differing hydrogen bond distances. Infrared bands at 3511 and 3359 cm−1 are ascribed to the OH stretching vibration of the OH units. Very broad bands at 3022 and 3299 cm−1 are attributed to the OH stretching vibrations of water. Vibrational spectroscopy offers insights into the molecular structure of the phosphate mineral kidwellite.

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Nitrogenated carbon nanotips with a low atomic concentration of nitrogen have been synthesized by using a custom-designed plasma-enhanced hot-filament plasma chemical vapor deposition system. The properties (including morphology, structure, composition, photoluminescence, etc.) of the synthesized nitrogenated carbon nanotips are investigated using advanced characterization tools. The room-temperature photoluminescence measurements show that the nitrogenated carbon nanotips can generate two distinct broad emissions located at ∼405 and ∼507 nm, respectively. Through the detailed analysis, it is shown that these two emission bands are attributed to the transition between the lone pair valence and bands, which are related to the sp3 and sp2 C-N bonds, respectively. These results are highly relevant to advanced applications of nitrogenated carbon nanotips in light emitting optoelectronic devices.

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Al-doped zinc oxide (AZO) thin films are deposited onto glass substrates using radio-frequency reactive magnetron sputtering and the improvements in their physical properties by post-synthesis thermal treatment are reported. X-ray diffraction spectra show that the structure of films can be controlled by adjusting the annealing temperatures, with the best crystallinity obtained at 400°C under a nitrogen atmosphere. These films exhibit improved quality and better optical transmittance as indicated by the UV-Vis spectra. Furthermore, the sheet resistivity is found to decrease from 1.87 × 10-3 to 5.63 × 10-4Ω⋅cm and the carrier mobility increases from 6.47 to 13.43 cm2 ⋅ V-1 ⋅ s-1 at the optimal annealing temperature. Our results demonstrate a simple yet effective way in controlling the structural, optical and electrical properties of AZO thin films, which is important for solar cell applications.

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The ability to inhibit unwanted actions is a heritable executive function that may confer risk to disorders such as attention deficit hyperactivity disorder (ADHD). Converging evidence from pharmacology and cognitive neuroscience suggests that response inhibition is instantiated within frontostriatal circuits of the brain with patterns of activity that are modulated by the catecholamines dopamine and noradrenaline. A total of 405 healthy adult participants performed the stop-signal task, a paradigmatic measure of response inhibition that yields an index of the latency of inhibition, termed the stop-signal reaction time (SSRT). Using this phenotype, we tested for genetic association, performing high-density single-nucleotide polymorphism mapping across the full range of autosomal catecholamine genes. Fifty participants also underwent functional magnetic resonance imaging to establish the impact of associated alleles on brain and behaviour. Allelic variation in polymorphisms of the dopamine transporter gene (SLC6A3: rs37020; rs460000) predicted individual differences in SSRT, after corrections for multiple comparisons. Furthermore, activity in frontal regions (anterior frontal, superior frontal and superior medial gyri) and caudate varied additively with the T-allele of rs37020. The influence of genetic variation in SLC6A3 on the development of frontostriatal inhibition networks may represent a key risk mechanism for disorders of behavioural inhibition.

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BACKGROUND AND OBJECTIVES Polymorphisms of the VEGF gene are known to affect the biological behaviour of cancers but have seldom been studied in thyroid cancer. The aim of the current study is to evaluate the prevalence and relevance of VEGF-A polymorphisms and mRNA expression in papillary thyroid carcinoma (PTC). MATERIALS AND METHODS Genomic DNA and total RNA were isolated from paraffin-embedded tissue from 91 PTC (51 conventional PTC and 40 follicular variant) and 78 control thyroid tissues. Three DNA polymorphisms (+936C > T, +405C > G and -141A > C) in the 3' and 5' untranslated region (3'-UTR, 5'-UTR) of VEGF-A were studied using PCR and RFLP. Also, the mRNA expression of VEGF-A in these tissues was studied by real-time PCR. RESULTS Distribution of polymorphisms in the 5'-UTR (VEGF-VEGF -141A > C and +405C > G) and 3'-UTR (VEGF +936C > T) were all significantly different in PTC and benign thyroid tissue (p = 0.0001, 0.001 and 0.028 respectively). The VEGF -141 C allele was more common in PTC with lymph node metastases (p = 0.026). VEGF + 405 Galleles andVEGF +936 CC genotype were more common in PTC of advanced pathological staging (p = 0.018 and 0.017 respectively). Also, increased expression of VEGF-A mRNA was noted in PTC compared to control (p = 0.009). Within the group of patients with conventional PTC, those with lymph nodal metastases had a higher level of VEGF-A mRNA expression than other patients (p = 0.0003). CONCLUSION These findings suggest that VEGF polymorphisms and mRNA expression may predict the aggressiveness behaviour of thyroid cancer.

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Recent controversy on the quantum dots dephasing mechanisms (between pure and inelastic) is re-examined by isolating the quantum dots from their substrate by using the appropriate limits of the ionization energy theory and the quantum adiabatic theorem. When the phonons in the quantum dots are isolated adiabatically from the phonons in the substrate, the elastic or pure dephasing becomes the dominant mechanism. On the other hand, for the case where the phonons from the substrate are non-adiabatically coupled to the quantum dots, the inelastic dephasing process takes over. This switch-over is due to different elemental composition in quantum dots as compared to its substrate. We also provide unambiguous analysis as to understand why GaAs/AlGaAs quantum dots may only have pure dephasing while InAs/GaAs quantum dots give rise to the inelastic dephasing as the dominant mechanism. It is shown that the elemental composition plays an important role (of both quantum dots and substrate) in evaluating the dephasing mechanisms of quantum dots.