933 resultados para Oil well cement


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Background: Previous studies have found significant stressors experienced by nurses working in haemodialysis units yet renal nurses appear to report less burnout than other nurses. Objectives: This study aims to undertake an inductive process to better understand the stressors and the coping strategies used by renal nurses that may lead to resilience. Method: Sixteen haemodialysis nurses from a metropolitan Australian hospital and two satellite units participated in open-ended interviews. Data were analysed from a grounded theory methodology. Measures of burnout and resilience were also obtained. Results: Two major categories of stressors emerged. First, due to prolonged patient contact, family-like relationships developed that lead to the blurring of boundaries. Second, participants experienced discrimination from both patients and staff. Despite these stressors, the majority of participants reported low burnout and moderately high-to-high levels of resilience. The major coping strategy that appeared to promote resilience was emotional distancing, while emotional detachment appeared to promote burn-out. Conclusion: Assisting nurses to use emotional distancing, rather than emotional detachment strategies to engender a sense of personal achievement may promote resilience.

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Examined communication between frail older people and their caregiving spouses (CGSs), and its relation to well-being in older care receivers. 53 community residing spousal dyads completed questionnaires about their well-being, relational satisfaction, and communication patterns. Conversations between the dyads were also videotaped and analyzed. The type of communication used by the CGSs was influenced by their sex, their earlier relationship with their spouse, and their level of well-being. CGSs who used an overly directive communication tone with their spouse were likely to be wives and CGSs who had a high degree of autonomy in their earlier relationship with their spouse. Low levels of life satisfaction and high affect balance in CGSs were associated with CGSs using a more patronizing tone. The well-being of care receivers was also related to their perceptions of their CGSs' communication. Care receivers who perceived their CGSs' communication as patronizing reported low levels of affect balance and high levels of conflict in the relationship. Findings suggest that certain characteristics of CGSs are related to the type of communication they use when conversing with their partner, although the relations are not always as expected.

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The ability to estimate the asset reliability and the probability of failure is critical to reducing maintenance costs, operation downtime, and safety hazards. Predicting the survival time and the probability of failure in future time is an indispensable requirement in prognostics and asset health management. In traditional reliability models, the lifetime of an asset is estimated using failure event data, alone; however, statistically sufficient failure event data are often difficult to attain in real-life situations due to poor data management, effective preventive maintenance, and the small population of identical assets in use. Condition indicators and operating environment indicators are two types of covariate data that are normally obtained in addition to failure event and suspended data. These data contain significant information about the state and health of an asset. Condition indicators reflect the level of degradation of assets while operating environment indicators accelerate or decelerate the lifetime of assets. When these data are available, an alternative approach to the traditional reliability analysis is the modelling of condition indicators and operating environment indicators and their failure-generating mechanisms using a covariate-based hazard model. The literature review indicates that a number of covariate-based hazard models have been developed. All of these existing covariate-based hazard models were developed based on the principle theory of the Proportional Hazard Model (PHM). However, most of these models have not attracted much attention in the field of machinery prognostics. Moreover, due to the prominence of PHM, attempts at developing alternative models, to some extent, have been stifled, although a number of alternative models to PHM have been suggested. The existing covariate-based hazard models neglect to fully utilise three types of asset health information (including failure event data (i.e. observed and/or suspended), condition data, and operating environment data) into a model to have more effective hazard and reliability predictions. In addition, current research shows that condition indicators and operating environment indicators have different characteristics and they are non-homogeneous covariate data. Condition indicators act as response variables (or dependent variables) whereas operating environment indicators act as explanatory variables (or independent variables). However, these non-homogenous covariate data were modelled in the same way for hazard prediction in the existing covariate-based hazard models. The related and yet more imperative question is how both of these indicators should be effectively modelled and integrated into the covariate-based hazard model. This work presents a new approach for addressing the aforementioned challenges. The new covariate-based hazard model, which termed as Explicit Hazard Model (EHM), explicitly and effectively incorporates all three available asset health information into the modelling of hazard and reliability predictions and also drives the relationship between actual asset health and condition measurements as well as operating environment measurements. The theoretical development of the model and its parameter estimation method are demonstrated in this work. EHM assumes that the baseline hazard is a function of the both time and condition indicators. Condition indicators provide information about the health condition of an asset; therefore they update and reform the baseline hazard of EHM according to the health state of asset at given time t. Some examples of condition indicators are the vibration of rotating machinery, the level of metal particles in engine oil analysis, and wear in a component, to name but a few. Operating environment indicators in this model are failure accelerators and/or decelerators that are included in the covariate function of EHM and may increase or decrease the value of the hazard from the baseline hazard. These indicators caused by the environment in which an asset operates, and that have not been explicitly identified by the condition indicators (e.g. Loads, environmental stresses, and other dynamically changing environment factors). While the effects of operating environment indicators could be nought in EHM; condition indicators could emerge because these indicators are observed and measured as long as an asset is operational and survived. EHM has several advantages over the existing covariate-based hazard models. One is this model utilises three different sources of asset health data (i.e. population characteristics, condition indicators, and operating environment indicators) to effectively predict hazard and reliability. Another is that EHM explicitly investigates the relationship between condition and operating environment indicators associated with the hazard of an asset. Furthermore, the proportionality assumption, which most of the covariate-based hazard models suffer from it, does not exist in EHM. According to the sample size of failure/suspension times, EHM is extended into two forms: semi-parametric and non-parametric. The semi-parametric EHM assumes a specified lifetime distribution (i.e. Weibull distribution) in the form of the baseline hazard. However, for more industry applications, due to sparse failure event data of assets, the analysis of such data often involves complex distributional shapes about which little is known. Therefore, to avoid the restrictive assumption of the semi-parametric EHM about assuming a specified lifetime distribution for failure event histories, the non-parametric EHM, which is a distribution free model, has been developed. The development of EHM into two forms is another merit of the model. A case study was conducted using laboratory experiment data to validate the practicality of the both semi-parametric and non-parametric EHMs. The performance of the newly-developed models is appraised using the comparison amongst the estimated results of these models and the other existing covariate-based hazard models. The comparison results demonstrated that both the semi-parametric and non-parametric EHMs outperform the existing covariate-based hazard models. Future research directions regarding to the new parameter estimation method in the case of time-dependent effects of covariates and missing data, application of EHM in both repairable and non-repairable systems using field data, and a decision support model in which linked to the estimated reliability results, are also identified.

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Despite the compelling case for moving towards cloud computing, the upstream oil & gas industry faces several technical challenges—most notably, a pronounced emphasis on data security, a reliance on extremely large data sets, and significant legacy investments in information technology infrastructure—that make a full migration to the public cloud difficult at present. Private and hybrid cloud solutions have consequently emerged within the industry to yield as much benefit from cloud-based technologies as possible while working within these constraints. This paper argues, however, that the move to private and hybrid clouds will very likely prove only to be a temporary stepping stone in the industry's technological evolution. By presenting evidence from other market sectors that have faced similar challenges in their journey to the cloud, we propose that enabling technologies and conditions will probably fall into place in a way that makes the public cloud a far more attractive option for the upstream oil & gas industry in the years ahead. The paper concludes with a discussion about the implications of this projected shift towards the public cloud, and calls for more of the industry's services to be offered through cloud-based “apps.”

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As the financial planning industry undergoes a series of reforms aimed at increased professionalism and improved quality of advice, financial planner training in Australia and elsewhere has begun to acknowledge the importance of interdisciplinary knowledge bases in informing both curriculum design and professoinal practice (e.g. FPA2009). This paper underscores the importance of the process of financial planning by providing a conceptual analysis of the six step financial planning process using key mechanisms derived from theory and research in cognate disciplines such as psychology and well-being. The paper identifies how these mechanisms may operate to impact client well-being in the financial planning context. The conceptual mapping of th emechanisms to process elements of financial planning is a unique contribution to the financial planning literature and offers a further framework in the armamentarium of researchers interested in pursuing questions around the value of financial planning. The conceptual framework derived from the analysis also adds to the growing body of literature aimed at developing an integrated model of financial planning.

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A salutogenic approach explored themes of strength and well-being in life stories of Burmese refugees (N = 18) in Australia. Previous refugee studies have tended to focus on negative responses to traumatic events (e.g. posttraumatic stress disorder, depression). To widen the scope of refugee related research the focus of the current study was informed by a salutogenic perspective, exploring sources of strength that may facilitate well-being. Semi-structured narrative interviews explored: the participant's life before fleeing Burma, the journey of exile, and post-migration in Australia. Eight women and 10 men (Mage = 39 years) were interviewed and transcriptions analysis of narratives was conducted using Interpretative Phenomenological Analysis (IPA), with major themes being explicated. Super-ordinate themes pertaining to strength during times of hardship were identified and explicated as: support from interpersonal relationships, the pivotal role of values, a sense of future and agency, and reliance on spiritual or religious beliefs. Results indicate the existence of sources of strength that may contribute to human responses in times of hardship. Recognition and reflection of strengths may be incorporated into therapeutic and resettlement approaches for people from refugee backgrounds.

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Postburn itch is reported to affect up to 87% of the burn population. Although treatments for postburn itch are multimodal, they remain consistently ineffective. However, recent anecdotal evidence from several outpatients at a tertiary referral hospital suggests that a cream combining beeswax and several herbal oils may be effective in the minimization of postburn itch. The aim of this study was to test the efficacy of beeswax and herbal oil cream against the standard treatment of aqueous cream in the provision of relief from the symptoms of postburn itch. A randomized controlled trial compared two groups using a visual analog scale, frequency of cream application, itch recurrence after cream application, use of antipruritic medications, and sleep disturbance to determine the effect of itch severity and duration. Fifty-two participants were enrolled in the study (84% male) with a mean age of 35 years (SD = 16) and mean burn TBSA of 7.2% (SD = 7.7). Study results found that the beeswax and herbal oil cream reduce itch after application more frequently than aqueous cream (P = .001). In addition, when managed with beeswax and herbal oil cream, participants found that their itch recurred later (P ≤ .001) and their use of antipruritic medications was lower (P = .023). Findings of this study suggest beeswax and herbal oil cream to be more effective in the minimization of postburn itch than aqueous cream. Given this, a larger study examining the efficacy of beeswax and herbal oil cream appears warranted.

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The aim of this study was to perform a biomechanical analysis of the cement-in-cement (c-in-c) technique for fixation of selected Vancouver Type B1 femoral periprosthetic fractures and to assess the degree of cement interposition at the fracture site. Six embalmed cadaveric femora were implanted with a cemented femoral stem. Vancouver Type B1 fractures were created by applying a combined axial and rotational load to failure. The femora were repaired using the c-in-c technique and reloaded to failure. The mean primary fracture torque was 117 Nm (SD 16.6, range 89–133). The mean revision fracture torque was 50 Nm (SD 16.6, range 29–74), which is above the torque previously observed for activities of daily living. Cement interposition at the fracture site was found to be minimal.

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This study explored the flexural performance of an innovative Hybrid Composite Floor Plate System (HCFPS), comprised of Polyurethane (PU) core, outer layers of Glass-fibre Reinforced Cement (GRC) and steel laminates at tensile regions, using experimental testing and Finite Element (FE) modelling. Bending and cyclic loading tests for the HCFPS panels and a comprehensive material testing program for component materials were carried out. HCFPS test panel exhibited ductile behaviour and flexural failure with a deflection ductility index of 4. FE models of HCFPS were developed using the program ABAQUS and validated with experimental results. The governing criteria of stiffness and flexural performance of HCFPS can be improved by enhancing the properties of component materials. HCFPS is 50-70% lighter in weight when compared to conventional floor systems. This study shows that HCFPS can be used for floor structures in commercial and residential buildings as an alternative to conventional steel concrete composite systems.

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The current study explored the effect of depression, optimism, and anxiety on job-related affective well-being in 70 graduate nurses. It was predicted that depression and anxiety would have a significant negative effect on job-related affective well-being, whereas optimism would have a significant positive effect on job-related affective well-being. Questionnaires were completed online or in hard-copy forms. Results revealed that depression, optimism, and anxiety were all significantly correlated to job-related affective well-being in the expected direction however, depression was found to be the only variable that made a significant unique contribution to the prediction of job-related affective well-being. Possible explanations for these findings are explored.

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The Beauty Leaf tree (Calophyllum inophyllum) is a potential source of non-edible vegetable oil for producing future generation biodiesel because of its ability to grow in a wide range of climate conditions, easy cultivation, high fruit production rate, and the high oil content in the seed. This plant naturally occurs in the coastal areas of Queensland and the Northern Territory in Australia, and is also widespread in south-east Asia, India and Sri Lanka. Although Beauty Leaf is traditionally used as a source of timber and orientation plant, its potential as a source of second generation biodiesel is yet to be exploited. In this study, the extraction process from the Beauty Leaf oil seed has been optimised in terms of seed preparation, moisture content and oil extraction methods. The two methods that have been considered to extract oil from the seed kernel are mechanical oil extraction using an electric powered screw press, and chemical oil extraction using n-hexane as an oil solvent. The study found that seed preparation has a significant impact on oil yields, especially in the screw press extraction method. Kernels prepared to 15% moisture content provided the highest oil yields for both extraction methods. Mechanical extraction using the screw press can produce oil from correctly prepared product at a low cost, however overall this method is ineffective with relatively low oil yields. Chemical extraction was found to be a very effective method for oil extraction for its consistence performance and high oil yield, but cost of production was relatively higher due to the high cost of solvent. However, a solvent recycle system can be implemented to reduce the production cost of Beauty Leaf biodiesel. The findings of this study are expected to serve as the basis from which industrial scale biodiesel production from Beauty Leaf can be made.

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This thesis investigates the role of narrative devices in the process of improving an individual’s psychological and physiological experience of health and well-being using two methods of inquiry: a theoretical research project and a comparative analysis of two case studies. Through these two approaches the research examines how the health status of people experiencing disability can be re-positioned and re-designed to develop creative, narrative-based approaches to strengthen communication between the mainstream community and those marginalised by pathological, social and biological illness-centric policy. The theoretical section of the thesis examines two different, but complementary bodies of research: health and well-being, and narrative reconstruction. By invoking Antonovksy’s (1985a) theory of salutogenesis and Davis’s (2002) theory of dismodernism, the study examines the role of language and narrative in the defining of health in social, pathological and ableist spheres. The research positions health and well-being as disparate from historical and contemporary readings of illness and disability and presents literature to support the potential to improve health well-being through a creative re-narration of the experience of disability. The research examines the theoretical concepts of resilience, autonomy and social inclusion through a detailed examination of narratology and the amnesty narrative. The study links these theoretical approaches to a practical Arts-Health intersection program developed for the research project called Communicating Personal Amnesty. Through a comparative analysis of a Pilot Study and Major Case study, the research presents findings derived from theory-building participatory action research showing the efficacy of the program. The research provides a detailed analysis of key narrative structures through a variety of experimental methodological approaches to encourage an important dialogue between the creative components of the thesis and the more traditional health-based academic critique. The research is an example of emergent translational health methodologies, in disability studies.

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Bird coastal communities were studied along Bribie Island and Moreton Island, two islands within Moreton Bay, Brisbane, Queensland, Australia, using the point counts method. A total of 128 five-hundred metre radius area surveys and 81 beach drive surveys were conducted and observations made over four seasons. Bird species were identified, counted and recorded. The data was compared between the two islands and, between sites on each island as oil-spill affected sites to non-oil spill affected sites. Species such as waders, shorebirds, terns/gulls and raptors were identified as species at most risk from an oil spill and the data was selected to look mainly at these species. The data indicated that sites affected by the oil spill contained 50% less oil-affected species than sites not affected by the oil spill. Bribie Island held on average 5 species per site in the oil affected sites compared to 12 species in non-oil affected sites. This same trend was observed on Moreton Island which held 6 species compared to 14 species. Bird data will continue to be counted over several years to determine whether the observed data is a true reflection of the affects of an oil spill on the habitat of shorebirds.

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Bioceramics play an important role in repairing and regenerating bone defects. Annually, more than 500,000 bone graft procedures are performed in the United states and approximately 2.2 million are conducted worldwide. The estimated cost of these procedures approaches $2.5billion per year. Around 60% of the bone graft substitutes available on the market involve bioceramics. It is reported that bioceramics in the world market increase by 9% per year. For this reason, the research of bioceramics has been one of the most active areas during, the past several years. Considering the significant importance of bioceramics, our goal was to compile this book to review the latest research advances in the field of bioceramics. The text also summarizes our work during the past 10 years in an effort to share innovative concepts, design of bioceramisc, and methods for material synthesis and drug delivery. We anticipate that this text will provide some useful information and guidance in the bioceramics field for biomedical engineering researchers and material scientists. Information on novel mesoporous bioactive glasses and silicate-based ceramics for bone regeneration and drug delivery are presented. Mesoporous bioactive glasses have shown multifunctional characteristics of bone regeneration and drug delivery due to their special mesopore structures,whereas silicated-based bioceramics, as typical third-generation biomaterials,possess significant osteostimulation properties. Silica nanospheres with a core-shell structure and specific properties for controllable drug delivery have been carefully reviewed-a variety of advanced synthetic strategies have been developed to construct functional mesoporous silica nanoparticles with a core-shell structure, including hollow, magnetic, or luminescent, and other multifunctional core-shell mesoporous silica nanoparticles. In addition, multifunctional drug delivery systems based on these nanoparticles have been designed and optimized to deliver the drugs into the targeted organs or cells,with a controllable release fashioned by virtue of various internal and external triggers. The novel 3D-printing technique to prepare advanced bioceramic scaffolds for bone tissue engineering applications has been highlighted, including the preparation, mechanical strength, and biological properties of 3D-printed porous scaffolds of calcium phosphate cement and silicate bioceramics. Three-dimensional printing techniques offer improved large-pore structure and mechanical strength. In addition , biomimetic preparation and controllable crystal growth as well as biomineralization of bioceramics are summarized, showing the latest research progress in this area. Finally, inorganic and organic composite materials are reviewed for bone regeneration and gene delivery. Bioactive inorganic and organic composite materials offer unique biological, electrical, and mechanical properties for designing excellent bone regeneration or gene delivery systems. It is our sincere hope that this book will updated the reader as to the research progress of bioceramics and their applications in bone repair and regeneration. It will be the best reward to all the contributors of this book if their efforts herein in some way help reader in any part of their study, research, and career development.