956 resultados para Current-source inverter (CSI)
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This study investigates the variability in response of optically stimulated luminescence dosimeters (OSLDs). Examining the source of sensitivity variations in these dosimeters allows for a more comprehensive understanding of the Landauer nanoDots and their potential for current and future applications. In this work, OSLDs were scanned with a MicroCT scanner to determine potential sources for the variation in relative sensitivity across a selection of Landauer nanoDot dosimeters. Specifically, the correlation between a dosimeters relative sensitivity and the loading density of Al2O3:C powder was determined. When extrapolating the sensitive volume's radiodensity from the CT data, it was shown that there is a non-uniform distribution in crystal growth. It was calculated that a 0.05% change in the nominal volume of the chip produces a 1% change in the overall response. Additionally, the ‘true’ volume of an OSLD's sensitive material is, on average, 18% less than that which has been reported in literature, mainly due to the presence of air cavities in the material's structure. This work demonstrated that the amount of sensitive material is approximately linked to the total correction factor.
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The contact lens industry has evolved and now provides many choices, including continuous wear, overnight orthokeratology, frequent-replacement lenses, daily-disposable lenses, and many alternatives in systems of care and maintenance. Epidemiologic studies to date have shown that how a lens is worn, particularly if worn overnight, can increase the risk of microbial keratitis. However, the risk of silicone hydrogel contact lenses worn on a continuous-wear basis has been evaluated only recently. This article summarizes the recent research data on extended-wear silicone hydrogel lenses and discusses the challenges of early evaluations of silicone hydrogel lens safety. Finally, the relevance of this information is discussed to practitioners and contact lens wearers making choices about the risks and benefits of different products and how they are used.
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The Interleukin-23 (IL-23)/IL-23R signaling axis is an important inflammatory pathway, involved in the stimulation and regulation of the T helper (Th) 17 lymphocytes, resulting in the production of IL-17. Aside from auto-immunity, this cytokine has also been linked to carcinogenesis and polymorphisms in the IL-23R gene are associated with an increased risk for the development of a number of different cancers. Activation of the IL-23 pathway results in the up-regulation of STAT3 and it is thought that the pathological consequences associated with this are in part due to the production of IL-17. We have previously identified IL-23A as pro-proliferative and epigenetically regulated in non-small cell lung cancer (NSCLC). The current study aims to evaluate IL-23R in greater detail in NSCLC. We demonstrate that IL-23R is expressed and epigenetically regulated in NSCLC through histone post-translation modifications and CpG island methylation. In addition, Gemcitabine treatment, a chemotherapy drug used in the treatment of NSCLC, resulted in the up-regulation of the IL-23R. Furthermore, Apilimod (STA 5326), a small molecule which blocks the expression of IL-23 and IL-12, reduced the proliferative capacity of NSCLC cells, particularly in the adenocarcinoma (A549) sub-type. Apilimod is currently undergoing investigation in a number of clinical trials for the treatment of auto-immune conditions such as Crohn's disease and Rheumatoid Arthritis. Our results may have implications for treating NSCLC patients with Gemcitabine or epigenetic targeted therapies. However, Apilimod may possibly provide a new treatment avenue for NSCLC patients. Work is currently ongoing to further delineate the IL-23/IL-23R axis in this disease.
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Modern health information systems can generate several exabytes of patient data, the so called "Health Big Data", per year. Many health managers and experts believe that with the data, it is possible to easily discover useful knowledge to improve health policies, increase patient safety and eliminate redundancies and unnecessary costs. The objective of this paper is to discuss the characteristics of Health Big Data as well as the challenges and solutions for health Big Data Analytics (BDA) – the process of extracting knowledge from sets of Health Big Data – and to design and evaluate a pipelined framework for use as a guideline/reference in health BDA.
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Debilitating infectious diseases caused by Chlamydia are major contributors to the decline of Australia's iconic native marsupial species, the koala (Phascolarctos cinereus). An understanding of koala chlamydial disease pathogenesis and the development of effective strategies to control infections continue to be hindered by an almost complete lack of species-specific immunological reagents. The cell-mediated immune response has been shown to play an influential role in the response to chlamydial infection in other hosts. The objective of this study, hence, was to provide preliminary data on the role of two key cytokines, pro-inflammatory tumour necrosis factor alpha (TNFα) and anti-inflammatory interleukin 10 (IL10), in the koala Chlamydia pecorum response. Utilising sequence homology between the cytokine sequences obtained from several recently sequenced marsupial genomes, this report describes the first mRNA sequences of any koala cytokine and the development of koala specific TNFα and IL10 real-time PCR assays to measure the expression of these genes from koala samples. In preliminary studies comparing wild koalas with overt chlamydial disease, previous evidence of C. pecorum infection or no signs of C. pecorum infection, we revealed strong but variable expression of TNFα and IL10 in wild koalas with current signs of chlamydiosis. The description of these assays and the preliminary data on the cell-mediated immune response of koalas to chlamydial infection paves the way for future studies characterising the koala immune response to a range of its pathogens while providing reagents to assist with measuring the efficacy of ongoing attempts to develop a koala chlamydial vaccine.
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This book examines the interface between religion, charity law and human rights. It does so by treating the Church of England and its current circumstances as a timely case study providing an opportunity to examine the tensions that have now become such a characteristic feature of that interface. Firstly, it suggests that the Church is the primary source of canon law principles that have played a formative role in shaping civic morality throughout the common law jurisdictions: the history of their emergence and enforcement by the State in post-Reformation England is recorded and assessed. Secondly, it reveals that of such principles those of greatest weight were associated with matters of sexuality: in particular, for centuries, family law was formulated and applied with regard for the sanctity of the heterosexual marital family which provided the only legally permissible context for any form of sexual relationship. Thirdly, given that history, it identifies and assesses the particular implications that now arise for the Church as a consequence of recent charity law reform outcomes and human rights case law developments: a comparative analysis of religion related case law is provided. Finally, following an outline of the structure and organizational functions of the Church, a detailed analysis is undertaken of its success in engaging with these issues in the context of the Lambeth Conferences, the wider Anglican Communion and in the ill-fated Covenant initiative. From the perspective of the dilemmas currently challenging the moral authority of the Church of England, this book identifies and explores the contemporary ‘moral imperatives’ or red line issues that now threaten the coherence of Christian religions in most leading common law nations. Gay marriage and abortion are among the host of morally charged and deeply divisive topics demanding a reasoned response and leadership from religious bodies. Attention is given to the judicial interpretation and evaluation of these and other issues that now undermine the traditional role of the Church of England. As the interface between religion, charity law and human rights becomes steadily more fractious, with religious fundamentalism and discrimination acquiring a higher profile, there is now a pressing need for a more balanced relationship between those with and those without religious beliefs. This book will be an invaluable aid in starting the process of achieving a triangulated relationship between the principles of canon law, charity law and human rights law.
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Links between human health and wellbeing, and contact with nature are well understood in the fields of health and psychology, and more recently are gaining attention in the built environment industry. In 1984, E.O. Wilson coined the term ‘biophilia’ to describe the tendency for humans to have an innately emotional response to other living organisms. A growing number of researchers around the world are now exploring the impact of nature in urban environments (i.e. biophilic urbanism) on the human condition, including many indicators of human physical and mental health, recovery and performance. There is also an emergence of research on the potential for biophilic urbanism to address other challenges related to climate change mitigation and adaptation. This paper presents key findings from a review of key literature to date, discussing opportunities for biophilic urbanism to both improve occupant experience and performance, as well as addressing other sustainability objectives including climate change mitigation and adaptation. The paper presents an emerging framework for considering biophilic design opportunities and highlights implications for the built environment industry. This research draws on an Australian project considering biophilic urbanism in the response to climate change, within the Sustainable Built Environment National Research Centre. This includes findings from a literature review, a survey pilot study and two workshops undertaken in Perth and Brisbane with a variety of industry and government stakeholders.
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To obtain accurate Monte Carlo simulations of small radiation fields, it is important model the initial source parameters (electron energy and spot size) accurately. However recent studies have shown that small field dosimetry correction factors are insensitive to these parameters. The aim of this work is to extend this concept to test if these parameters affect dose perturbations in general, which is important for detector design and calculating perturbation correction factors. The EGSnrc C++ user code cavity was used for all simulations. Varying amounts of air between 0 and 2 mm were deliberately introduced upstream to a diode and the dose perturbation caused by the air was quantified. These simulations were then repeated using a range of initial electron energies (5.5 to 7.0 MeV) and electron spot sizes (0.7 to 2.2 FWHM). The resultant dose perturbations were large. For example 2 mm of air caused a dose reduction of up to 31% when simulated with a 6 mm field size. However these values did not vary by more than 2 % when simulated across the full range of source parameters tested. If a detector is modified by the introduction of air, one can be confident that the response of the detector will be the same across all similar linear accelerators and the Monte Carlo modelling of each machine is not required.
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Network coding is a method for achieving channel capacity in networks. The key idea is to allow network routers to linearly mix packets as they traverse the network so that recipients receive linear combinations of packets. Network coded systems are vulnerable to pollution attacks where a single malicious node floods the network with bad packets and prevents the receiver from decoding correctly. Cryptographic defenses to these problems are based on homomorphic signatures and MACs. These proposals, however, cannot handle mixing of packets from multiple sources, which is needed to achieve the full benefits of network coding. In this paper we address integrity of multi-source mixing. We propose a security model for this setting and provide a generic construction.
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In this introductory chapter to Schmeinck, D. and Lidstone, J. (2014) “Current trends and issues in geographical education” in Schmeinck, D. and Lidstone, J. (2014) Eds) Standards and Research in Geographical Education: Current Trends and International Issues. Berlin. Mensch und Buch Verlag. Pp. 5 - 16. , the authors review and analyse eleven papers originally presented to the Congress of the International Geographical Union held in Cologne in 2012. Taking the collection of papers as a single corpus representing the “state of the art” of geography education, they applied lexical and bibliometric analyses in an innovative attempt to identify the nature of geographical education as represented by this anthology of peer reviewed chapters presented at the start of the second decade of the Twenty-first century?
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What is the state of geographical education in the second decade of the 21st century? This volume presents a selection of peer reviewed papers presented at the 2012 Cologne Congress of the International Geographical Union (IGU) sessions on Geographical Education as representative of current thinking in the area. It then presents (perhaps for the first time) a cross-case analysis of the common factors of all these papers as a current summary of the “state of the art” of geographical education today. The primary aim of the individual authors as well as the editors is not only to record the current state of the art of geographical education but also to promote ongoing discussions of the longer term health and future prospects of international geographical education. We wish to encourage ongoing debate and discussion amongst local, national, regional and international education journals, conferences and discussion groups as part of the international mission of the Commission on Geographical Eduction. While the currency of these chapters in terms of their foci, breadth and recency of the theoretical literature on which they are based and the new research findings they present justifies considerable confidence in the current health of geographical education as an educational and research endeavour, each new publication should only be the start of new scholarly inquiry. Where should we, as a scholarly community, place our energies for the future? If readers are left with a new sense of direction, then the aims of the authors and editors will have been amply met.
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Arguing for the importance of understanding the conditions under which certain forms of the social subject become visible and viable, this chapter conceptualises the current educational focus on ‘creativity’ as a technology of governmentality that has arisen from the perceived need for governing authorities to manage and responsibilise populations for the pervasive uncertainties of the global economy. With reference to the document, Tough Choices or Tough Times, a publication of the National Center on Education and the Economy in the United States, we show how creativity has been reframed as a programmable capacity of the modern student, citizen and worker primarily because it is considered an indispensible source of enterprise and innovation. Education and family life are an integral part of this bio-politics and the ongoing ‘economisation’ of social life. Our concern is that this reductionist understanding of creativity precludes other transgressive and culturally enriching creativities that represent the infinite range of subjectivities associated with imaginative human capacity and activity. It is vital therefore that educational research renders this historical process transparent and opens spaces for more socially inclusive, sustainable and productive ways of being such as those indicated by the three respondees.
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M. fortuitum is a rapidly growing mycobacterium associated with community-acquired and nosocomial wound, soft tissue, and pulmonary infections. It has been postulated that water has been the source of infection especially in the hospital setting. The aim of this study was to determine if municipal water may be the source of community-acquired or nosocomial infections in the Brisbane area. Between 2007 and 2009, 20 strains of M. fortuitum were recovered from municipal water and 53 patients’ isolates were submitted to the reference laboratory. A wide variation in strain types was identified using repetitive element sequence-based PCR, with 13 clusters of ≥2 indistinguishable isolates, and 28 patterns consisting of individual isolates. The clusters could be grouped into seven similar groups (>95% similarity). Municipal water and clinical isolates collected during the same time period and from the same geographical area consisted of different strain types, making municipal water an unlikely source of sporadic human infection.
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Background How accurately do people perceive extreme water speeds and how does their perception affect perceived risk? Prior research has focused on the characteristics of moving water that can reduce human stability or balance. The current research presents the first experiment on people's perceptions of risk and moving water at different speeds and depths. Methods Using a randomized within-person 2 (water depth: 0.45, 0.90 m) ×3 (water speed: 0.4, 0.8, 1.2 m/s) experiment, we immersed 76 people in moving water and asked them to estimate water speed and the risk they felt. Results Multilevel modeling showed that people increasingly overestimated water speeds as actual water speeds increased or as water depth increased. Water speed perceptions mediated the direct positive relationship between actual water speeds and perceptions of risk; the faster the moving water, the greater the perceived risk. Participants' prior experience with rip currents and tropical cyclones moderated the strength of the actual–perceived water speed relationship; consequently, mediation was stronger for people who had experienced no rip currents or fewer storms. Conclusions These findings provide a clearer understanding of water speed and risk perception, which may help communicate the risks associated with anticipated floods and tropical cyclones.
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Capture fisheries and aquaculture have been a major source of food and providers of economic benefits to many communities around the world for a very long time. While the history of aquaculture or fish farming can be traced back for more than 2000 years in some corners of the globe, notably in China, Japan and the Mediterranean, this is not true everywhere, where in general, fish farming is a relatively new industry. Rapid human population growth and increasing urbanisation over the last 20 to 40 years has meant that while fish consumption has doubled globally, returns from capture fisheries have remained static or have declined due to overexploitation and rising pollution levels, with some fisheries either closing or becoming economically unviable. Data from studies suggest that this trend is unlikely to be reversed unless appropriate fisheries management allows depleted wild stocks to rebuild. This has occurred during a time when demand for fish products has grown, in part due to improved purchasing power in some developing countries and changing dietary habits where fish are now considered to have a positive impact on health. Based on the projected population growth over the next two decades, Food and Agricultural Organization (FAO) estimates that at least an additional 40 million tonnes of aquatic food will be required to maintain the current per capita consumption (FAO 2006).