981 resultados para Failure investigation
Resumo:
Background: Heart failure is a serious condition estimated to affect 1.5-2.0% of the Australian population with a point prevalence of approximately 1% in people aged 50-59 years, 10% in people aged 65 years or more and over 50% in people aged 85 years or over (National Heart Foundation of Australian and the Cardiac Society of Australia and New Zealand, 2006). Sleep disturbances are a common complaint of persons with heart failure. Disturbances of sleep can worsen heart failure symptoms, impair independence, reduce quality of life and lead to increased health care utilisation in patients with heart failure. Previous studies have identified exercise as a possible treatment for poor sleep in patients without cardiac disease however there is limited evidence of the effect of this form of treatment in heart failure. Aim: The primary objective of this study was to examine the effect of a supervised, hospital-based exercise training programme on subjective sleep quality in heart failure patients. Secondary objectives were to examine the association between changes in sleep quality and changes in depression, exercise performance and body mass index. Methods: The sample for the study was recruited from metropolitan and regional heart failure services across Brisbane, Queensland. Patients with a recent heart failure related hospital admission who met study inclusion criteria were recruited. Participants were screened by specialist heart failure exercise staff at each site to ensure exercise safety prior to study enrolment. Demographic data, medical history, medications, Pittsburgh Sleep Quality Index score, Geriatric Depression Score, exercise performance (six minute walk test), weight and height were collected at Baseline. Pittsburgh Sleep Quality Index score, Geriatric Depression Score, exercise performance and weight were repeated at 3 months. One hundred and six patients admitted to hospital with heart failure were randomly allocated to a 3-month disease-based management programme of education and self-management support including standard exercise advice (Control) or to the same disease management programme as the Control group with the addition of a tailored physical activity program (Intervention). The intervention consisted of 1 hour of aerobic and resistance exercise twice a week. Programs were designed and supervised by an exercise specialist. The main outcome measure was achievement of a clinically significant change (.3 points) in global Pittsburgh Sleep Quality score. Results: Intervention group participants reported significantly greater clinical improvement in global sleep quality than Control (p=0.016). These patients also exhibited significant improvements in component sleep disturbance (p=0.004), component sleep quality (p=0.015) and global sleep quality (p=0.032) after 3 months of supervised exercise intervention. Improvements in sleep quality correlated with improvements in depression (p<0.001) and six minute walk distance (p=0.04). When study results were examined categorically, with subjects classified as either "poor" or "good" sleepers, subjects in the Control group were significantly more likely to report "poor" sleep at 3 months (p=0.039) while Intervention participants were likely to report "good" sleep at this time (p=0.08). Conclusion: Three months of supervised, hospital based, aerobic and resistance exercise training improved subjective sleep quality in patients with heart failure. This is the first randomised controlled trial to examine the role of aerobic and resistance exercise training in the improvement of sleep quality for patients with this disease. While this study establishes exercise as a therapy for poor sleep quality, further research is needed to investigate the effect of exercise training on objective parameters of sleep in this population.
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With a monolayer honeycomb-lattice of sp2-hybridized carbon atoms, graphene has demonstrated exceptional electrical, mechanical and thermal properties. One of its promising applications is to create graphene-polymer nanocomposites with tailored mechanical and physical properties. In general, the mechanical properties of graphene nanofiller as well as graphene-polymer interface govern the overall mechanical performance of graphene-polymer nanocomposites. However, the strengthening and toughening mechanisms in these novel nanocomposites have not been well understood. In this work, the deformation and failure of graphene sheet and graphene-polymer interface were investigated using molecular dynamics (MD) simulations. The effect of structural defects on the mechanical properties of graphene and graphene-polymer interface was investigated as well. The results showed that structural defects in graphene (e.g. Stone-Wales defect and multi-vacancy defect) can significantly deteriorate the fracture strength of graphene but may still make full utilization of corresponding strength of graphene and keep the interfacial strength and the overall mechanical performance of graphene-polymer nanocomposites.
Resumo:
Remote monitoring for heart failure has been evaluated in numerous systematic reviews. The aim of this meta-review was to appraise their quality and synthesise results. We electronically searched online databases, performed a forward citation search and hand-searched bibliographies. Systematic reviews of remote monitoring interventions that were used for surveillance of heart failure patients were included. Seven (41%) systematic reviews pooled results for meta-analysis. Eight (47%) considered all non-invasive remote monitoring strategies. Five (29%) focused on telemonitoring. Four (24%) included both non-invasive and invasive technologies. According to AMSTAR criteria, ten (58%) systematic reviews were of poor methodological quality. In high quality reviews, the relative risk of mortality in patients who received remote monitoring ranged from 0.53 (95% CI=0.29-0.96) to 0.88 (95% CI=0.76-1.01). High quality reviews also reported that remote monitoring reduced the relative risk of all-cause (0.52; 95% CI=0.28-0.96 to 0.96; 95% CI=0.90–1.03) and heart failure-related hospitalizations (0.72; 95% CI=0.64–0.81 to RR 0.79; 95% CI=0.67-0.94) and, as a consequence, healthcare costs. As the high quality reviews reported that remote monitoring reduced hospitalizations, mortality and healthcare costs, research efforts should now be directed towards optimising these interventions in preparation for more widespread implementation.
Resumo:
Background/aims: Remote monitoring for heart failure has not only been evaluated in a large number of randomised controlled trials, but also in many systematic reviews and meta-analyses. The aim of this meta-review was to identify, appraise and synthesise existing systematic reviews that have evaluated the effects of remote monitoring in heart failure. Methods: Using a Cochrane methodology, we electronically searched all relevant online databases and search engines, performed a forward citation search as well as hand-searched bibliographies. Only fully published systematic reviews of invasive and/or non-invasive remote monitoring interventions were included. Two reviewers independently extracted data. Results: Sixty-five publications from 3333 citations were identified. Seventeen fulfilled the inclusion and exclusion criteria. Quality varied with A Measurement Tool to Assess Systematic Reviews (AMSTAR scores) ranging from 2 to 11 (mean 5.88). Seven reviews (41%) pooled results from individual studies for meta-analysis. Eight (47%) considered all non-invasive remote monitoring strategies. Four (24%) focused specifically on telemonitoring. Four (24%) included studies investigating both non-invasive and invasive technologies. Population characteristics of the included studies were not reported consistently. Mortality and hospitalisations were the most frequently reported outcomes 12 (70%). Only five reviews (29%) reported healthcare costs and compliance. A high degree of heterogeneity was reported in many of the meta-analyses. Conclusions: These results should be considered in context of two negative RCTs of remote monitoring for heart failure that have been published since the meta-analyses (TIM-HF and Tele-HF). However, high quality reviews demonstrated improved mortality, quality of life, reduction in hospitalisations and healthcare costs.
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A range of authors from the risk management, crisis management, and crisis communications literature have proposed different models as a means of understanding components of crisis. A generic component of these sources has focused on preparedness practices before disturbance events and response practices during events. This paper provides a critical analysis of three key explanatory models of how crises escalate highlighting the strengths and limitations of each approach. The paper introduces an optimised conceptual model utilising components from the previous work under the four phases of pre-event, response, recovery, and post-event. Within these four phases, a ten step process is introduced that can enhance understanding of the progression of distinct stages of disturbance for different types of events. This crisis evolution framework is examined as a means to provide clarity and applicability to a range of infrastructure failure contexts and provide a path for further empirical investigation in this area.
Resumo:
In this paper we use the algorithm SeqSLAM to address the question, how little and what quality of visual information is needed to localize along a familiar route? We conduct a comprehensive investigation of place recognition performance on seven datasets while varying image resolution (primarily 1 to 512 pixel images), pixel bit depth, field of view, motion blur, image compression and matching sequence length. Results confirm that place recognition using single images or short image sequences is poor, but improves to match or exceed current benchmarks as the matching sequence length increases. We then present place recognition results from two experiments where low-quality imagery is directly caused by sensor limitations; in one, place recognition is achieved along an unlit mountain road by using noisy, long-exposure blurred images, and in the other, two single pixel light sensors are used to localize in an indoor environment. We also show failure modes caused by pose variance and sequence aliasing, and discuss ways in which they may be overcome. By showing how place recognition along a route is feasible even with severely degraded image sequences, we hope to provoke a re-examination of how we develop and test future localization and mapping systems.
Resumo:
We have developed an explanation for ultra trace detection found when using Au/Ag SERS nanoparticles linked to biochemical affinity tags, e.g. antibodies. The nanoparticle structure is not as usually assumed and the aggregated nanoparticles constitute hot spots that are indispensable for these very low levels of analyte detection, even more so when using a direct detection method.
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Many Australian families are unable to access homeownership. This is because house prices are very high to the severely or seriously unaffordable level. Therefore, many low income families will need to rely on affordable rental housing supply. The Australian governments introduced National Rental Affordability Scheme (NRAS) in July 2008. The scheme aims to increase the supply of affordable rental housing by 50,000 dwellings across Australia by June 2014. It provides financial incentive for investors to purchase new affordable housing that must be rented at a minimum of 20% below the market rent. The scheme has been in place for four years to June 2012. There are debates on the success or failure of the scheme. One argues that the scheme is more successful in Queensland but it failed to meet its aims in NSW. This paper examines NRAS incentive designed to encourage affordable housing supply in Australia and demonstrates reasons for developing properties that are crowded in areas where the land prices are relatively lower in the NSW using a discounted cash flow analysis in a hypothetical case study. The findings suggest that the high land values and the increasing cost of development were the main constraints of implementing the scheme in the NSW and government should not provide a flat rate subsidy which is inadequate to ensure that affordable housing projects in high cost areas.
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This PhD practice-led research inquiry sets out to examine and describe how the fluid interactions between memory and time can be rendered via the remediation of my painting and the construction of a digital image archive. My abstract digital art and handcrafted practice is informed by Deleuze and Guattari’s rhizomics of becoming. I aim to show that the technological mobility of my creative strategies produce new conditions of artistic possibility through the mobile principles of rhizomic interconnection, multiplicity and diversity. Subsequently through the ongoing modification of past painting I map how emergent forms and ideas open up new and incisive engagements with the experience of a ‘continual present’. The deployment of new media and cross media processes in my art also deterritorialises the modernist notion of painting as a static and two dimensional spatial object. Instead, it shows painting in a postmodern field of dynamic and transformative intermediality through digital formats of still and moving images that re-imagines the relationship between memory, time and creative practice.
Resumo:
Distal radius fractures stabilized by open reduction internal fixation (ORIF) have become increasingly common. There is currently no consensus on the optimal time to commence range of motion (ROM) exercises post-ORIF. A retrospective cohort review was conducted over a five-year period to compare wrist and forearm range of motion outcomes and number of therapy sessions between patients who commenced active ROM exercises within the first seven days and from day eight onward following ORIF of distal radius fractures. One hundred and twenty-one patient cases were identified. Clinical data, active ROM at initial and discharge therapy assessments, fracture type, surgical approaches, and number of therapy sessions attended were recorded. One hundred and seven (88.4%) cases had complete datasets. The early active ROM group (n = 37) commenced ROM a mean (SD) of 4.27 (1.8) days post-ORIF. The comparator group (n = 70) commenced ROM exercises 24.3 (13.6) days post-ORIF. No significant differences were identified between groups in ROM at initial or discharge assessments, or therapy sessions attended. The results from this study indicate that patients who commenced active ROM exercises an average of 24 days after surgery achieved comparable ROM outcomes with similar number of therapy sessions to those who commenced ROM exercises within the first week.
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This paper deals with the failure of high adhesive, low compressive strength, thin layered polymer mortar joints in masonry through a contact modelling in finite element framework. Failure due to combined shear, tensile and compressive stresses are considered through a constitutive damaging contact model that incorporates traction–separation as a function of displacement discontinuity. The modelling method is verified using single and multiple contact analyses of thin mortar layered masonry specimens under shear, tensile and compressive stresses and their combinations. Using this verified method, the failure of thin mortar layered masonry under a range of shear to tension ratios and shear to compression ratios has been examined. Finally, this model is applied to thin bed masonry wallettes for their behaviour under biaxial tension–tension and compression–tension loadings perpendicular and parallel to the bed joints.
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Following the growing need for adoption of alternative fuels, this project aimed at getting more information on the oxidative potential of biodiesel particulate matter. Within this scope, the physical and chemical characteristics of biodiesel PM were analysed which lead to identification of reactive organic fractions. An in-house developed proflurescent nitroxide probe was used. This project further developed in-depth understanding of the chemical mechanisms following the detection of the oxidative potential of PM. This knowledge made a significant contribution to our understanding of processes behind negative health effects of pollution and enabled us to further develop new techniques to monitor it.
Resumo:
The reaction of pyrrole and thiophene monomers with copper- or nickel-exchanged mordenite has been investigated using X-ray photoelectron (XPS) and photoacoustic infrared (PAIRS) spectroscopies. Because of the differing oxidising powers of the cations studied, polymerisation occurred only with copper-exchanged mordenite. PAIRS and XPS data indicated that both polypyrrole and polythiophene were partially oxidised when synthesised within the zeolite structure. IR spectra of polythiophene and polythiophene and polypyrrole showed intense bands typical of ring vibrations which could couple to the large dipole change induced by charges moving along the polythiophene chain. In addition it was noted that only vibrations typical of oxidised polymer structures were recorded, suggesting that the charge carrier was located within these segments. Furthermore, N 1s spectra contained a high binding energy peak at 402.5 eV which was attributed to a positively charged nitrogen species, in agreement with IR data. Significantly, C 1s spectra confirmed that molecular wires were formed within the confines of the zeolite lattice. Depth-profiling experiments suggested that polypyrrole was distributed throughout the entire zeolite host. By contrast, polythiophene may have been restricted to the uppermost zeolite channels owing to the ability of sulfur species to bond to CuI sites [produced by reduction of copper(II) ions during the polymerisation process], thus obstructing movement along the channels.
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Background: In diabetes care, health care professionals need to provide support for their patients. In order to provide good diabetes self-management support for adults with type 2 diabetes in Vietnam, it is important that health care professionals in Vietnam understand the factors influencing diabetes self-management among these people. However, knowledge about factors influencing diabetes self-management among adults with type 2 diabetes in Vietnam is limited. Objectives: This study aimed to investigate factors influencing diabetes self-management among adults with type 2 diabetes in Vietnam. Methodology: A cross-sectional survey with convenience sampling was conducted on 198 adults with type 2 diabetes in VietnamData collection was administeted via interview. Descriptive statistics, simple correlation statistics and structural equation modelling statistics were used for data analysis. Results: Adults with type 2 diabetes in Vietnam had limited diabetes knowledge (Median = 6.0). The majority of the study participants (72.7%) believed that performing diabetes self-management activities was very important or extremely important for controlling their blood glucose levels and for preventing complications from diabetes; about half usually received support from their family and friends’ (48.5%), and around two thirds rarely received support from their health care providers (68.2%). Many of the participants (41.4%) had limited confidence to perform diabetes management activities. The practices of diabetes self-management were limited among the study population (Mean = 96.7, SD = 19.4). Diabetes knowledge (β = 0.17, p < .001), belief in treatment effectiveness (β = 0.13, p < .01), family and friends’ support (β = 0.13, p < .001), health care providers’ support (β = 0.27, p < .001) and diabetes management self-efficacy (β = 0.43, p < .001) directly influenced their diabetes self-management. Diabetes knowledge, and family and friends’ support also indirectly influenced diabetes self-management among these people through their belief in treatment effectiveness and their diabetes management self-efficacy (p < .05). Conclusion: Findings in this study indicated that health care professionals should provide diabetes self-management support for adults with type 2 diabetes in Vietnam in the future. The adapted theory-based model of factors influencing diabetes self-management among adults with type 2 diabetes in Vietnam found in this study could be a useful framework to develop this supporting program.
Resumo:
Intensive Care Paramedics (ICPs) attend to only the most clinically challenging of emergency medical cases, often working in a chaotic and frenetic atmosphere. They are regularly exposed to human tragedy and with that, the potential to experience traumatic events is not uncommon. There is very little known about the well-being of ICPs; how they cope with the demands of their role, or about their mental health in general. Nineteen experienced ICPs (4 female, 15 male) participated in a semi-structured interview. Themes were extracted from the data using an Interpretive Phenomenological Analysis approach. All participants discussed a work-related event they attended that traumatized them, usually experienced in the earlier parts of their career. Some spoke of an immediate overwhelming of their capacity to cope and others of a gradual onset of traumatic stress when reflecting on the event at a later time. More than half of the participants described events that involved children as the most difficult. Data revealed four superordinate themes: Social Support, Cognitive Coping, Proactive Coping, and Long Term Effects. Each superordinate theme comprised a number of constituent themes which are presented in this paper and exemplified with participant quotes. Although ongoing distress was described by some participants, all of the ICPs interviewed discussed positive aspects of their job; things that made the role worthwhile and fulfilling. This research highlights the important factors involved in coping with, and growing from, the extraordinary events that ICPs face. Results have implications for employing organizations and staff support services as well as for paramedics more broadly as they learn to cope with events inherent in their career. Findings indicate that positive adaptation and personal growth as a result of exposure to extremely high levels of potentially traumatic experiences is not only possible, but highly probable.