438 resultados para IMAGING SURVEY


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PURPOSE: To compare the repeatability within anterior corneal topography measurements and agreement between measurements with the Pentacam HR rotating Scheimpflug camera and with a previously validated Placido disk–based videokeratoscope (Medmont E300). ------ SETTING: Contact Lens and Visual Optics Laboratory, School of Optometry, Queensland University of Technology, Brisbane, Queensland, Australia. ----- METHODS: Normal eyes in 101 young adult subjects had corneal topography measured using the Scheimpflug camera (6 repeated measurements) and videokeratoscope (4 repeated measurements). The best-fitting axial power corneal spherocylinder was calculated and converted into power vectors. Corneal higher-order aberrations (HOAs) (up to the 8th Zernike order) were calculated using the corneal elevation data from each instrument. ----- RESULTS: Both instruments showed excellent repeatability for axial power spherocylinder measurements (repeatability coefficients <0.25 diopter; intraclass correlation coefficients >0.9) and good agreement for all power vectors. Agreement between the 2 instruments was closest when the mean of multiple measurements was used in analysis. For corneal HOAs, both instruments showed reasonable repeatability for most aberration terms and good correlation and agreement for many aberrations (eg, spherical aberration, coma, higher-order root mean square). For other aberrations (eg, trefoil and tetrafoil), the 2 instruments showed relatively poor agreement. ----- CONCLUSIONS: For normal corneas, the Scheimpflug system showed excellent repeatability and reasonable agreement with a previously validated videokeratoscope for the anterior corneal axial curvature best-fitting spherocylinder and several corneal HOAs. However, for certain aberrations with higher azimuthal frequencies, the Scheimpflug system had poor agreement with the videokeratoscope; thus, caution should be used when interpreting these corneal aberrations with the Scheimpflug system.

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This book aims to provide an overview of approaches to assist researchers and practitioners to explore ways of undertaking research in the information literacy field. The first chapter provides an introductory overview of research by Dr Kirsty Williamson (author of Research Methods for Students, Academics and Professionals: Information Management and Systems) and this sets the scene for the rest of the chapters where each author explores the key aspects of a specific method and explains how it may be applied in practice. The methods covered include those representing qualitative, quantitative and mixed methods. Both a chapter on the topical evidence-based practice approach, and another critiquing it, are also included. The final chapter points the way towards potential new directions for the burgeoning field

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Many high-rise office buildings have been built in Surabaya. The investors have provided complimentary facilities to satisfy their tenants. However, not all given facilities has satisfied the tenants. The purpose of this study is to find out the level of tenant satisfaction in office “X” to the existing facilities and to suggest additional required facilities. Although office “X” is offered the highest rental rate and has known as a prestigious place in Surabaya, only location and public transport have satisfied the Indonesian tenants. Meanwhile, the multi National companies have not satisfied for any existing facilities. Additional ATM facilities and presentable cafeteria, improvement of service and the security system are required by tenants.

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Free-radical processes underpin the thermo-oxidative degradation of polyolefins. Thus, to extend the lifetime of these polymers, stabilizers are generally added during processing to scavenge the free radicals formed as the polymer degrades. Nitroxide radical precursors, such as hindered amine stabilizers (HAS),1,2 are common polypropylene additives as the nitroxide moiety is a potent scavenger of polymer alkyl radicals (R¥). Oxidation of HAS by radicals formed during polypropylene degradation yields nitroxide radicals (RRNO¥), which rapidly trap the polymer degradation species to produce alkoxyamines, thus retarding oxidative polymer degradation. This increase in polymer stability is demonstrated by a lengthening of the “induction period” of the polymer (the time prior to a sharp rise in the oxidation of the polymer). Instrumental techniques such as chemiluminescence or infrared spectroscopy are somewhat limited in detecting changes in the polymer during the initial stages of degradation. Therefore, other methods for observing polymer degradation have been sought as the useful life of a polymer does not extend far beyond its “induction period”

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Background: Chronic venous leg ulcers have a significant impact on older individuals’ well-being and health care resources. Unfortunately after healing, up to 70% recur. ----- Objective: To examine the relationships between leg ulcer recurrence and physical activity, compression, nutrition, health, psychosocial indicators and self-care activities in order to provide information for preventive strategies. ----- Design: Survey and retrospective chart review Settings: Two metropolitan hospital and three community-based leg ulcer clinics. ----- Subjects: A sample of 122 community living patients with leg ulcer of venous aetiology which had healed between 12 and 36 months prior to the survey. ---- Methods: Data were collected from medical records on demographics, medical history and previous ulcer history and treatments; and from self-report questionnaires on physical activity, nutrition, psychosocial measures, ulcer recurrences and history, compression and other self-care activities. All variables significantly associated with recurrence at the bivariate level were entered into a logistic regression model to determine their independent influences on recurrence. ----- Results: Median follow-up time was 24 months (range 12–40 months). Sixty-eight percent of participants had recurred. Bivariate analysis found recurrence was positively associated with ulcer duration, cardiac disease, a Body Mass Index ≤20, scoring as at-risk of malnutrition and depression; and negatively associated with increased physical activity, leg elevation, wearing Class 2 (20–25mmHg) or Class 3 (30–40mmHg) compression hosiery, and higher self-efficacy scores. After adjusting for all variables, an hour/day of leg elevation (OR=0.04, 95% CI=0.01–0.17), days/week in Class 2 or 3 compression hosiery (OR=0.53, 95% CI=0.34–0.81), Yale Physical Activity Survey score (OR=0.95, 95% CI=0.92–0.98), cardiac disease (OR=5.03, 95% CI=1.01–24.93) and General Self-Efficacy scores (OR=0.83, 95% CI=0.72–0.94) remained significantly associated (p<0.05) with recurrence. ----- Conclusions: Results indicate a history of cardiac disease is a risk factor for recurrence; while leg elevation, physical activity, compression hosiery and strategies to improve self-efficacy are likely to prevent recurrence.

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This article presents a survey of authorisation models and considers their ‘fitness-for-purpose’ in facilitating information sharing. Network-supported information sharing is an important technical capability that underpins collaboration in support of dynamic and unpredictable activities such as emergency response, national security, infrastructure protection, supply chain integration and emerging business models based on the concept of a ‘virtual organisation’. The article argues that present authorisation models are inflexible and poorly scalable in such dynamic environments due to their assumption that the future needs of the system can be predicted, which in turn justifies the use of persistent authorisation policies. The article outlines the motivation and requirement for a new flexible authorisation model that addresses the needs of information sharing. It proposes that a flexible and scalable authorisation model must allow an explicit specification of the objectives of the system and access decisions must be made based on a late trade-off analysis between these explicit objectives. A research agenda for the proposed Objective-based Access Control concept is presented.

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This paper examines voter attitudes and behaviour at the 2007 Australian federal election., using data from the Australian Election Study. It considers socio-demographic factors as well as the role of policy issues and voter evaluations of the party leaders. The paper concludes that issues, such as the government's WorkChoices policy, as well as health and leadership contributed to Labor's victory.

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While a number of factors have been highlighted in the innovation adoption literature, little is known about the key triggers of innovation adoption across differently-sized firms. This study compares case studies of small, medium and large manufacturing firms who recently decided to adopt a process innovation. We also employ organizational surveys from 134 firms investigating the factors which influence innovation adoption. The quantitative results support the qualitative findings that the external pressures are a trigger among small to medium firms, while the larger firm’s adoption was associated with internal causes.

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A technique is described whereby micro-ATR/FTIR imaging can be used to follow polymer degradation reactions in situ in real time. The internal reflection element (IRE) assembly is removed from the ATR objective and polymer is solvent cast directly onto the IRE surface. The polymer is then subjected to degradation conditions and molecular structural changes monitored by periodically replacing the IRE assembly back in the ATR objective and collecting spectra which can be used to construct images. This approach has the benefit that the same part of the sample is always studied, and that contact by pressure which might damage the polymer surface is not required. The technique is demonstrated using the polymer Topas which was degraded by exposure to UVC light in air.

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Geriatric nursing competency in the acute care setting is a social mandate for the 21st century. This article reports on the content validation of an Australian research instrument, the Older Patients in Acute Care Survey (OPACS) that examines the attitudes, the knowledge, and the practices of nurses working with acute care patients. The OPACS tool was developed primarily to assist nurse educators to assess attitudes, knowledge, and practices of nursing staff in caring for older patients in the acute care setting; to evaluate the implementation of institution-specific educational interventions; and to improve quality of care given to older patients. An overall content validity index (CVI) for the OPACS was calculated (CVI = .918), revealing high content validity. Opinions (CVI = .92) and practices (CVI = .97) subconstructs revealed high content validity as well. Therefore, results indicate that the OPACS has high content validity in the U.S. acute care setting and could assist nurse educators in establishing and enhancing nurse competency in the care for geriatric patients in the future.

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Public knowledge and beliefs about injury prevention are currently poorly understood. A total of 1030 residents in the State of Queensland, Australia responded to questions about injury prevention in or around the home, on the roads, in or on the water, at work, deliberate injury, and responsibility for preventing deliberate injury allowing comparison with published injury prevalence data. Overall the youngest members of society were identified as being the most vulnerable to deliberate injury with young adults accounting for 59% of responses aligning with published data. However, younger adults failed to indicate an awareness of their own vulnerability to deliberate injury in alcohol environments even though 61% of older respondents were aware of this trend. Older respondents were the least inclined to agree that they could make a difference to their own safety in or around the home but were more inclined to agree that they could make a difference to their own safety at work. The results are discussed with a view to using improved awareness of public beliefs about injury to identify barriers to the uptake of injury prevention strategies (e.g. low perceived injury risk) as well as areas where injury prevention strategies may receive public support.

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Diffraction tomographic imaging is applied to the imaging of shallowly buried targets with multi-bistatic arrays of transmitters and receivers.