Showing papers by "University of Sydney published in 2004"
TL;DR: In this article, the prevalence and distribution of age-related macular degeneration (AMD) in the United States by age, race/ethnicity, and gender was estimated.
Abstract: Objective: To estimate the prevalence and distribution of age-related macular degeneration (AMD) in the United States by age, race/ethnicity, and gender.Methods: Summary prevalence estimates of drusen 125 pin or larger, neovascular AMD, and geographic atrophy were prepared separately for black and white persons in 5-year age intervals starting at 40 years. The estimated rates were based on a meta-analysis of recent population-based studies in the United States, Australia, and Europe. These rates were applied to 2000 US Census data and to projected US population figures for 2020 to estimate the number of the US population with drusen and AMD.Results: The overall prevalence of neovascular AMD and/or geographic atrophy in the US population 40 years and older is estimated to be 1.47% (95% confidence interval, 1.38%-1.55%), with 1.75 million citizens having AMD. The prevalence of AMD increased dramatically with age, with more than 15% of the white women older than 80 years having neovascular AMD and/or geographic atrophy. More than 7 million individuals had drusen measuring 125 pin or larger and were, therefore, at substantial risk of developing AMD. Owing to the rapidly aging population, the number of persons having AMD will increase by 50% to 2.95 million in 2020. Age-related macular degeneration was far more prevalent among white than among black persons.Conclusion: Age-related macular degeneration affects more than 1.75 million individuals in the United States. Owing to the rapid aging of the US population, this number will increase to almost 3 million by 2020.
2,389 citations
TL;DR: Simulated data sets were used to test the power and accuracy of Monte Carlo resampling methods in generating statistical thresholds for identifying F0 immigrants in populations with ongoing gene flow, and hence for providing direct, real‐time estimates of migration rates.
Abstract: Genetic assignment methods use genotype likelihoods to draw inference about where individuals were or were not born, potentially allowing direct, real-time estimates of dispersal. We used simulated data sets to test the power and accuracy of Monte Carlo resampling methods in generating statistical thresholds for identifying F0 immigrants in populations with ongoing gene flow, and hence for providing direct, real-time estimates of migration rates. The identification of accurate critical values required that resampling methods preserved the linkage disequilibrium deriving from recent generations of immigrants and reflected the sampling variance present in the data set being analysed. A novel Monte Carlo resampling method taking into account these aspects was proposed and its efficiency was evaluated. Power and error were relatively insensitive to the frequency assumed for missing alleles. Power to identify F0 immigrants was improved by using large sample size (up to about 50 individuals) and by sampling all populations from which migrants may have originated. A combination of plotting genotype likelihoods and calculating mean genotype likelihood ratios (DLR) appeared to be an effective way to predict whether F0 immigrants could be identified for a particular pair of populations using a given set of markers.
1,481 citations
TL;DR: Likelihood ratios are alternative statistics for summarising diagnostic accuracy, which have several particularly powerful properties that make them more useful clinically than other statistics.
Abstract: The properties of a diagnostic or screening test are often described using sensitivity and specificity or predictive values, as described in previous Notes.1 2 Likelihood ratios are alternative statistics for summarising diagnostic accuracy, which have several particularly powerful properties that make them more useful clinically than other statistics.3
Each test result has its own likelihood ratio, which summarises how many times more (or less) likely patients with the disease are to have that particular result than patients without the disease. More formally, it is the ratio of the probability of the specific test result in people who do have the disease to the probability in people who do not.
A likelihood ratio greater than 1 indicates that the test result is associated with the presence of the disease, whereas a likelihood ratio less than 1 indicates that the test result is associated with the absence of disease. The further likelihood ratios are from 1 the stronger the evidence for the presence or absence of disease. Likelihood ratios above 10 and below 0.1 are considered …
1,335 citations
TL;DR: Aesthetic attributes, convenience of facilities for walking, accessibility of destinations, and perceptions about traffic and busy roads were found to be associated with walking for particular purposes, and early evidence is promising.
1,301 citations
TL;DR: The prevention of the overproduction of NO in the living organism through control of regulatory pathways may assist in the treatment of high NO-mediated disorders without changing physiological levels of NO.
1,170 citations
TL;DR: Clinical and pathological findings in 12 patients with relapsing and remitting multiple sclerosis, who died during or shortly after the onset of a relapse, raise the possibility of some novel process underlying new lesion formation in multiple sclerosis.
Abstract: The study describes the clinical and pathological findings in 12 patients with relapsing and remitting multiple sclerosis, who died during or shortly after the onset of a relapse. Pathological changes not previously associated with the formation of new symptomatic lesions were observed in seven cases, namely, extensive oligodendrocyte apoptosis and microglial activation in myelinated tissue containing few or no lymphocytes or myelin phagocytes. No current laboratory model of multiple sclerosis, in particular, experimental allergic encephalomyelitis, is known with these features, which raises the possibility of some novel process underlying new lesion formation in multiple sclerosis.
1,146 citations
TL;DR: A broad range of strategies were recommended to reduce obesity prevalence including influencing the food supply to make healthy choices easier; reducing the marketing of energy dense foods and beverages to children; influencing urban environments and transport systems to promote physical activity.
Abstract: Objective: To review the evidence on the diet and nutrition causes of obesity and to recommend strategies to reduce obesity prevalence Design: The evidence for potential aetiological factors and strategies to reduce obesity prevalence was reviewed, and recommendations for public health action, population nutrition goals and further research were made Results: Protective factors against obesity were considered to be: regular physical activity (convincing); a high intake of dietary non-starch polysaccharides (NSP)/fibre (convincing); supportive home and school environments for children (probable); and breastfeeding (probable) Risk factors for obesity were considered to be sedentary lifestyles (convincing); a high intake of energy-dense, micronutrient-poor foods (convincing); heavy marketing of energy-dense foods and fast food outlets (probable); sugar-sweetened soft drinks and fruit juices (probable); adverse social and economic conditions—developed countries, especially in women (probable) A broad range of strategies were recommended to reduce obesity prevalence including: influencing the food supply to make healthy choices easier; reducing the marketing of energy dense foods and beverages to children; influencing urban environments and transport systems to promote physical activity; developing community-wide programmes in multiple settings; increased communications about healthy eating and physical activity; and improved health services to promote breastfeeding and manage currently overweight or obese people Conclusions: The increasing prevalence of obesity is a major health threat in both low- and high income countries Comprehensive programmes will be needed to turn the epidemic around
1,137 citations
TL;DR: There are several hybrid input-output analysis-based LCA methods that can be implemented in practice for broadening system boundary and also for ISO compliance.
Abstract: Life-cycle assessment (LCA) is a method for evaluating the environmental impacts of products holistically, including direct and supply chain impacts. The current LCA methodologies and the standards by the International Organization for Standardization (ISO) impose practical difficulties for drawing system boundaries; decisions on inclusion or exclusion of processes in an analysis (the cutoff criteria) are typically not made on a scientific basis. In particular, the requirement of deciding which processes could be excluded from the inventory can be rather difficult to meet because many excluded processes have often never been assessed by the practitioner, and therefore, their negligibility cannot be guaranteed. LCA studies utilizing economic input-output analysis have shown that, in practice, excluded processes can contribute as much to the product system under study as included processes; thus, the subjective determination of the system boundary may lead to invalid results. System boundaries in LCA are discussed herein with particular attention to outlining hybrid approaches as methods for resolving the boundary selection problem in LCA. An input-output model can be used to describe at least a part of a product system, and an ISO-compatible system boundary selection procedure can be designed by applying hybrid input-output-assisted approaches. There are several hybrid input-output analysis-based LCA methods that can be implemented in practice for broadening system boundary and also for ISO compliance.
964 citations
TL;DR: The EDE-Q has good concurrent validity and acceptable criterion validity, and the measure appears well-suited to use in prospective epidemiological studies.
964 citations
TL;DR: Reduced adiponectin level is associated with more extensive necroinflammation and may contribute to the development of necroinflammatory forms of NAFLD.
952 citations
TL;DR: This paper describes this concept as a recursive interrelationship between different environments, which, together with a model of constructive memory, provides the foundation of a situated FBS framework.
TL;DR: Microscope investigation and X-ray diffraction revealed the important role played by the tetragonal to monoclinic phase transformation and by the relationship between the glassy matrix and the crystalline phase in the strengthening and toughening mechanisms of these ceramics.
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TL;DR: In this paper, the authors examined how men and women differ in both their perceptions of the risks associated with shopping online and the effect of receiving a site recommendation from a friend, and found that having a site recommended by a friend leads to both a greater reduction in perceived risk and a stronger increase in willingness to buy online among women than among men.
Abstract: This article examines how men and women differ in both their perceptions of the risks associated with shopping online and the effect of receiving a site recommendation from a friend. The first study examines how gender affects the perceptions of the probability of negative outcomes and the severity of such negative outcomes should they occur for five risks associated with buying online (i.e., credit card misuse, fraudulent sites, loss of privacy, shipping problems, and product failure). The second study examines gender differences in the effect of receiving a recommendation from a friend on perceptions of online purchase risk. The third study experimentally tests whether, compared to men, women will be more likely to increase their willingness to purchase online if they receive a site recommendation from a friend. The results suggest that, even when controlling for differences in Internet usage, women perceive a higher level of risk in online purchasing than do men. In addition, having a site recommended by a friend leads to both a greater reduction in perceived risk and a stronger increase in willingness to buy online among women than among men.
TL;DR: Some of the recent findings on resistance mechanisms are summarized, some recommendations for limiting its impact are put forward and some priorities for research in this area are suggested.
TL;DR: The evidence that PA confers a positive benefit on health is updated, using research studies in the peer-reviewed scientific literature published between 2000-2003, including updates in all-cause mortality and in cardiovascular disease prevention, diabetes, stroke, mental health, falls and injuries, and in obesity prevention.
TL;DR: Observations of ALS4 suggest that mutations in SETX may cause neuronal degeneration through dysfunction of the helicase activity or other steps in RNA processing.
Abstract: Juvenile amyotrophic lateral sclerosis (ALS4) is a rare autosomal dominant form of juvenile amyotrophic lateral sclerosis (ALS) characterized by distal muscle weakness and atrophy, normal sensation, and pyramidal signs. Individuals affected with ALS4 usually have an onset of symptoms at age Senataxin gene ( SETX ). The SETX gene encodes a novel 302.8-kD protein. Although its function remains unknown, SETX contains a DNA/RNA helicase domain with strong homology to human RENT1 and IGHMBP2, two genes encoding proteins known to have roles in RNA processing. These observations of ALS4 suggest that mutations in SETX may cause neuronal degeneration through dysfunction of the helicase activity or other steps in RNA processing.
TL;DR: The emergence of this usually tropical pathogen on Vancouver Island highlights the changing distribution of this genotype and emphasizes the importance of an ongoing collaborative effort to monitor the global epidemiology of this yeast.
Abstract: Cryptococcus gattii causes life-threatening infection of the pulmonary and central nervous systems in hosts with normal immunity and traditionally has been considered to be restricted geographically to tropical and subtropical climates. The recent outbreak of C. gattii in the temperate climate of Vancouver Island, BC, Canada, led to a collaborative investigation. The objectives of the current study were to ascertain the environmental source of the outbreak infections, survey the molecular types of the outbreak and environmental cryptococcal isolates, and determine the extent of genetic diversity among the isolates. PCR-fingerprinting and amplified fragment length polymorphism (AFLP) were used to examine the genotypes, and mating assays were performed to determine the mating type of the isolates. All outbreak and environmental isolates belonged to C. gattii. Concordant results were obtained by using PCR-fingerprinting and AFLP analysis. The vast majority of clinical and veterinary infections were caused by isolates of the molecular type VGII/AFLP6, but two were caused by molecular type VGI/AFLP4. All environmental isolates belonged to molecular type VGII/AFLP6. Two or three subtypes were observed within VGII/AFLP6 among outbreak and environmental isolates. All mating-competent isolates were of the alpha-mating type. The emergence of this usually tropical pathogen on Vancouver Island highlights the changing distribution of this genotype and emphasizes the importance of an ongoing collaborative effort to monitor the global epidemiology of this yeast.
TL;DR: It is shown that when represented in the information form, map posteriors are dominated by a small number of links that tie together nearby features in the map, which is developed into a sparse variant of the EIF, called the sparse extended information filter (SEIF).
Abstract: In this paper we describe a scalable algorithm for the simultaneous mapping and localization (SLAM) problem. SLAM is the problem of acquiring a map of a static environment with a mobile robot. The vast majority of SLAM algorithms are based on the extended Kalman filter (EKF). In this paper we advocate an algorithm that relies on the dual of the EKF, the extended information filter (EIF). We show that when represented in the information form, map posteriors are dominated by a small number of links that tie together nearby features in the map. This insight is developed into a sparse variant of the EIF, called the sparse extended information filter (SEIF). SEIFs represent maps by graphical networks of features that are locally interconnected, where links represent relative information between pairs of nearby features, as well as information about the robot’s pose relative to the map. We show that all essential update equations in SEIFs can be executed in constant time, irrespective of the size of the map. We...
TL;DR: Gene microarrays reveal a highly distinctive transcriptional profile for a third subset of effector T cells that differs markedly from Th1 and Th2 cells.
Abstract: Effector T cell responses have long been viewed in the context of the Th1/Th2 paradigm. Recently, a third major subset of nonpolarized effector T cells that provides help to B cells has been identified. These T cells, termed T follicular helper (TFH) cells, home to the B cell areas of secondary lymphoid tissue, through interactions mediated via the chemokine receptor CXCR5 and its ligand CXCL13. Affymetrix microarrays were used to identify transcription factors, cytokines, and cell surface molecules that underlie the differentiation pathways and functional properties of the TFH subset. The transcriptional profile of human CXCR5+ TFH cells was compared with that of Th1 and Th2 cells, which enabled the identification of numerous genes expressed preferentially by TFH cells, over the other effector subsets. Certain TFH genes were also expressed by B cells and thus appear to be particularly relevant for humoral immunity. Abs were used to confirm the expression of several factors. In particular, CD84 and CD200, the cytokine IL-21, and the transcription factor BCL6 were all strongly associated with TFH cells. Gene microarrays reveal a highly distinctive transcriptional profile for a third subset of effector T cells that differs markedly from Th1 and Th2 cells.
TL;DR: In this article, the authors reviewed various advanced solar thermal electricity technologies with an emphasis on new technology and new market approaches, and made suggestions for more effective programmes of support for these technologies.
TL;DR: Heterotopic bone induction to form a mandibular replacement inside the latissimus dorsi muscle in a human being is possible and allows for a lower operative burden compared with conventional techniques by avoiding creation of a secondary bone defect.
TL;DR: This article found that Australian university teachers charged with responsibility for developing students' generic graduate attributes do not share a common understanding of either the nature of these outcomes, or the teaching and learning processes that might facilitate the development of these outcome.
Abstract: For many years universities around the world have sought to articulate the nature of the education they offer to their students through a description of the generic qualities and skills their graduates possess. Despite the lengthy history of the rhetoric of such policy claims, universities' endeavours to describe generic attributes of graduates continue to lack a clear theoretical or conceptual base and are characterized by a plurality of view-points. Furthermore, despite extensive funding in some quarters, overall, efforts to foster the development of generic attributes appear to have met with limited success. Recent research has shed some light on this apparent variability in policy and practice. It is apparent that Australian university teachers charged with responsibility for developing students' generic graduate attributes do not share a common understanding of either the nature of these outcomes, or the teaching and learning processes that might facilitate the development of these outcomes. Instead ...
TL;DR: In this article, the authors examined risk factors for incident age-related macular degeneration (AMD) after combining data from three population-based cohort studies and found that current smoking was associated with an increased risk of incident geographic atrophy, neovascular AMD, and late AMD.
Australian National University1, University of Edinburgh2, Macquarie University3, University of Sydney4, Harvard University5, California Institute of Technology6, University College London7, Durham University8, Centre national de la recherche scientifique9, Institut d'Astrophysique de Paris10, Gifu University11
TL;DR: The 6dF Galaxy Survey (6dFGS) as discussed by the authors is the largest survey of the nearby universe, reaching out to about z similar to 0.15, and more than an order of magnitude larger than any peculiar velocity survey to date.
Abstract: The 6dF Galaxy Survey (6dFGS) aims to measure the redshifts of around 150 000 galaxies, and the peculiar velocities of a 15 000-member subsample, over almost the entire southern sky. When complete, it will be the largest redshift survey of the nearby Universe, reaching out to about z similar to 0.15, and more than an order of magnitude larger than any peculiar velocity survey to date. The targets are all galaxies brighter than K-tot = 12.75 in the 2MASS Extended Source Catalog (XSC), supplemented by 2MASS and SuperCOSMOS galaxies that complete the sample to limits of (H, J, r(F), b(J)) = (13.05, 13.75, 15.6, 16.75). Central to the survey is the Six-Degree Field (6dF) multifibre spectrograph, an instrument able to record 150 simultaneous spectra over the 5.7-field of the UK Schmidt Telescope. An adaptive tiling algorithm has been employed to ensure around 95 per cent fibring completeness over the 17 046 deg(2) of the southern sky with \b\ > 10degrees. Spectra are obtained in two observations using separate V and R gratings, that together give R similar to 1000 over at least 4000-7500 Angstrom and signal-to-noise ratio similar to10 per pixel. Redshift measurements are obtained semi-automatically, and are assigned a quality value based on visual inspection. The 6dFGS data base is available at http://www-wfau.roe.ac.uk/6dFGS/, with public data releases occurring after the completion of each third of the survey.
TL;DR: The Approaches to Teaching Inventory (ATI) as discussed by the authors was developed from the research perspective applied by Marton and colleagues in Europe (Marton, F., Hounsell, D., and Entwistle, N. 1997) to student learning.
Abstract: This paper describes how research into approaches to university teaching, from a relational perspective, has been used to develop an inventory to measure the key aspects of the variation in approaches to teaching. The Approaches to Teaching Inventory (ATI) is one of several that derive from the research perspective applied by Marton and colleagues in Europe (Marton, F., Hounsell, D., and Entwistle, N. (eds.) (1997). The Experience of Learning, 2nd edn., Scottish Academic Press, Edinburgh) to student learning. A feature of these inventories is that they measure the response of a group to a particular context, rather than more general characteristics of individuals in that group. Studies using these inventories have consistently shown relations between students' approaches to learning and the quality of their learning outcome. The question of interest to many university teachers is whether there are relations between the way teachers approach their teaching and ways their students approach their learning. This question was answered in a study published in 1999 that used the ATI to show that teacher-focused approaches to teaching were associated with students' reproducing orientations. Subsequent research revealed that in subjects where teachers adopted more student-focused approaches to teaching, their students adopted a deeper approach to learning. Some recent research using the inventory is reviewed along with an analysis of the validity of the ATI. The current version of the inventory is reproduced in this paper.
TL;DR: The pathological substrate can be predicted in a significant proportion of FTD patients, which has important implications for studies targeting mechanistic treatments.
Abstract: The term frontotemporal dementia (FTD) encompasses a range of clinical syndromes that are believed not to map reliably onto the spectrum of recognized pathologies. This study reexamines the relationships between clinical and pathological subtypes of FTD in a large series from two centers (n = 61). Clinical subtypes defined were behavioral variant FTD (n = 26), language variants (semantic dementia, n = 9; and progressive nonfluent aphasia, n = 8), and motor variants (corticobasal degeneration, n = 9; and motor neuron disease, n = 9), although most cases presented with a combination of behavioral and language problems. Unexpectedly, some behavioral cases (n = 5) had marked amnesia at presentation. The pathological subtypes were those with tau-immunopositive inclusions (with Pick bodies, n = 20; or without, n = 11), those with ubiquitin immunopositive inclusions (n = 16), and those lacking distinctive histology (n = 14). Behavioral symptoms and semantic dementia were associated with a range of pathologies. In contrast, other clinical phenotypes had relatively uniform underlying pathologies: motor neuron disease predicted ubiquitinated inclusions, parkinsonism and apraxia predicted corticobasal pathology, and nonfluent aphasia predicted Pick bodies. Therefore, the pathological substrate can be predicted in a significant proportion of FTD patients, which has important implications for studies targeting mechanistic treatments.
TL;DR: Specific protein dimerization is integral to biological function, structure and control, and must be under substantial selection pressure to be maintained with such frequency throughout biology.
Space Telescope Science Institute1, University of Melbourne2, European Southern Observatory3, Australia Telescope National Facility4, University of Queensland5, Swinburne University of Technology6, University of Manchester7, University of Western Sydney8, Cardiff University9, Mount Stromlo Observatory10, University of Technology, Sydney11, University of New Mexico12, ASTRON13, University of Colorado Boulder14, University of Sydney15, University of Leicester16
TL;DR: The HIPASS catalogue as mentioned in this paper is the largest uniform catalogue of H I sources compiled to date, with 4315 sources identified purely by their H I content, and the catalogue data comprise the southern region δ< + 2 ◦ of HIPASS, the first blind H I survey to cover the entire southern sky.
Abstract: The H I Parkes All-Sky Survey (HIPASS) catalogue forms the largest uniform catalogue of H I sources compiled to date, with 4315 sources identified purely by their H I content. The catalogue data comprise the southern region δ< + 2 ◦ of HIPASS, the first blind H I survey to cover the entire southern sky. The rms noise for this survey is 13 mJy beam −1 and the velocity range is −1280 to 12 700 km s −1 . Data search, verification and parametrization methods are discussed along with a description of measured quantities. Full catalogue data are made available to the astronomical community including positions, velocities, velocity widths, integrated fluxes and peak flux densities. Also available are on-sky moment maps, position‐velocity moment maps and spectra of catalogue sources. A number of local large-scale features are observed in the space distribution of sources, including the super-Galactic plane and the Local Void. Notably, large-scale structure is seen at low Galactic latitudes, a region normally obscured at optical wavelengths.
TL;DR: The equations developed from this study appear to be applicable to adult dogs of most breeds, and appropriate mean values and prediction intervals were calculated for normal dogs, allowing veterinarians to correctly and appropriately index M-mode values.
Abstract: Indices for M-mode measurements in dogs usually have been based on the assumption that a linear relationship exists between these measurements and body weight (BW) or body surface area (BSA). The relationships between the geometry of 3-dimensional objects do not support this assumption. The purposes of this study were to retrospectively examine M-mode data from a large number of dogs of varying sizes and breeds that were examined by a large number of ultrasonographers, to use the allometric equation to determine the appropriate BW exponent required to predict these cardiac dimensions, and to determine normal mean values and prediction intervals for common M-mode variables. Linear regression analyses of data from 494 dogs (2.2-95 kg) revealed a good correlation between M-mode measurements and BW after logarithmic transformation of the data (r2 = .55-.88). Most variables were most closely related to an index of body length, BW(1/3), although the exponent that best predicted diastolic and systolic left ventricular wall thicknesses was closer to 0.25. No variable indexed well to BW or BSA. With these data, appropriate mean values and prediction intervals were calculated for normal dogs, allowing veterinarians to correctly and appropriately index M-mode values. The equations developed from this study appear to be applicable to adult dogs of most breeds.
TL;DR: In this article, the authors present quantitative estimates of microbial community turnover at local and regional scales using the largest spatially explicit microbial diversity data set available (> 10(6) sample pairs).
Abstract: Patterns in the spatial distribution of organisms provide important information about mechanisms that regulate the diversity of life and the complexity of ecosystems. Although microorganisms may comprise much of the Earth's biodiversity and have critical roles in biogeochemistry and ecosystem functioning, little is known about their spatial diversification. Here we present quantitative estimates of microbial community turnover at local and regional scales using the largest spatially explicit microbial diversity data set available (> 10(6) sample pairs). Turnover rates were small across large geographical distances, of similar magnitude when measured within distinct habitats, and did not increase going from one vegetation type to another. The taxa-area relationship of these terrestrial microbial eukaryotes was relatively flat (slope z = 0.074) and consistent with those reported in aquatic habitats. This suggests that despite high local diversity, microorganisms may have only moderate regional diversity. We show how turnover patterns can be used to project taxa-area relationships up to whole continents. Taxa dissimilarities across continents and between them would strengthen these projections. Such data do not yet exist, but would be feasible to collect.