253 resultados para oil well drilling


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Contemporary lipidomics protocols are dependent on conventional tandem mass spectrometry for lipid identification. This approach is extremely powerful for determining lipid class and identifying the number of carbons and the degree of unsaturation of any acyl-chain substituents. Such analyses are however, blind to isomeric variants arising from different carbon carbon bonding motifs within these chains including double bond position, chain branching, and cyclic structures. This limitation arises from the fact that conventional, low energy collision-induced dissociation of even-electron lipid ions does not give rise to product ions from intrachain fragmentation of the fatty acyl moieties. To overcome this limitation, we have applied radical-directed dissociation (RDD) to the study of lipids for the first time. In this approach, bifunctional molecules that contain a photocaged radical initiator and a lipid-adducting group, such as 4-iodoaniline and 4-iodobenzoic acid, are used to form noncovalent complexes (i.e., adduct ions) with a lipid during electrospray ionization. Laser irradiation of these complexes at UV wavelengths (266 nm) cleaves the carbon iodine bond to liberate a highly reactive phenyl radical. Subsequent activation of the nascent radical ions results in RDD with significant intrachain fragmentation of acyl moieties. This approach provides diagnostic fragments that are associated with the double bond position and the positions of chain branching in glycerophospholipids, sphingomyelins and triacylglycerols and thus can be used to differentiate isomeric lipids differing only in such motifs. RDD is demonstrated for well-defined lipid standards and also reveals lipid structural diversity in olive oil and human very-low density lipoprotein.

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Children and adolescents with intellectual disability have higher rates of mental health problems compared with there typically developing peers. Social support has been identified as an important protective factor for psychological well - being. In this paper we discuss the benefits of social support networks, and consider approaches for promoting children’s perceptions of the availability of social support. We describe an evidence-based intervention that has been specially adapted and implemented for students with intellectual disability in school settings. In a randomised controlled trial, the Aussie Optimism Resilience Skills Program was associated with improved perceptions of social support following a 10-week intervention. Educators need to be aware of the increased vulnerability of students with intellectual disability to the development mental health problems and the proactive ways in which they can promote psychological well - being within their classrooms.

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There are many attractive alternatives to produce chemicals similar to those currently produced from fossil fuel resources. The most viable renewable resource of fixed carbon is biomass. This paper examines processing conditions for the production and recovery of furanics from bagasse as well as bagasse pulp. It is shown that bio-oil consisting mainly of furanics (~84% chloromethly furfural) may be obtained in yields of ~78% and ~87% by weight from bagasse and bagasse pulp respectively using a biphasic acid hydrolysis system. The biphasic system consists of an organic layer of dichloroethane and an aqueous phase of concentrated hydrochloric acid. Generally the lower the impurity content and the higher the cellulose content, the higher the furanics yield.

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This project was a step forward in developing a 'descriptive theory' of contracting in the oil and gas industry that reflects the operating environment in which the project manager operates. This study investigates the existing processes and methods used in establishing contracts which are very often prescriptive, and not always appropriate or optimal for a given situation. This study contributes to contracting effectiveness or optimal contracting in the oil and gas industry.

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We explored whether teams develop shared perceptions regarding the quantity and quality of information and the extent of participation in decision making provided in an environment of continuous change. In addition, we examined whether change climate strength moderated relationships between change climate level and team outcomes. We examined relationships among aggregated change information and change participation and aggregated team outcomes, including two role stressors (i.e., role ambiguity and role overload) and two indicators of well-being (i.e., quality of worklife and distress). Questionnaires were distributed in an Australian law enforcement agency and data were used from 178 teams. Structural equation modelling analyses, controlling for a marker variable, were conducted to examine the main effects of aggregated change information and aggregated change participation on aggregated team outcomes. Results provided support for a model that included method effects due to a marker variable. In this model, change information climate was significantly negatively associated with role ambiguity, role overload, and distress, and significantly positively associated with quality of worklife. Change participation climate was significantly positively associated with quality of worklife. Change climate strength did not moderate relationships among change climate level and team outcomes.

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This paper presents the outcomes of an international collaboration between researchers and young people in Australia and the United States, using participatory design to engage young people as research partners in the collaborative development of a conceptual framework for the Online WellBeing Center (OWBC), a repository of evidence-based mental health tools focused on mental health promotion and the prevention of mental illness developed as part of Young and Well Cooperative Research Centre. Eighteen participants (nine in Australia and nine in USA) were involved as key partners through a series of participatory design workshops to develop the framework for the OWBC. Key objectives of the collaboration included an increased understanding of: how to recruit young people to be part of an international project team collaborating remotely; how to use new technologies to manage communication and maintain engagement; how to apply principles of participatory research to create a youth informed research project; how to develop an international stakeholder partnership to ensure relevancy in value systems, cultural orientation and project outcomes. Recommendations included guidelines for how others can establish international collaborations that integrate young people as active project participants.

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The purpose of the present study was to examine the types of workplace demands and resources experienced by full-time Australian lawyers, and the prevalence of a range of psychological outcomes. The study further focussed on the impact of time-billing targets on lawyers’ experience of these variables. Participants were 384 full-time Australian lawyers who completed an online questionnaire distributed by their Australian State or Territory Law Society. Analysis revealed that emphasis on profits within the workplace was the highest perceived demand, and the perception of social value in their work was the highest available resource. The results indicated that 37% of participants displayed Moderate to Extremely Severe depressive symptoms, and 35% were a positive screen for hazardous or harmful drinking. A series of three multivariate analyses of variance revealed significant differences between non-billers, low-to-moderate billers and high billers, with high billers experiencing greater demands, fewer resources and poorer psychological outcomes. The practical applications of these results for the legal profession are discussed.

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Background While adverse events primarily affect the patient, surgeons involved can also experience considerable distress. Aims The aim of the survey was to assess the impact of complications on the day-to-day life, work and health of Australian and New Zealand obstetricians and gynaecologists and to evaluate existing support systems and coping strategies. Methods A 43-question survey on self-assessment, quality assurance (QA) tools, impact of complications on individuals’ health and relationships, and support available was emailed to fellows, trainees, subspecialists and subspecialty trainees of the Royal Australian and New Zealand College of Obstetrics and Gynaecology (RANZCOG). We collected 606 responses from a target population of 2296 (response rate 26.3%). Results When complications occur, sleep was affected of 80%, family and social relationships of 55% and physical health of 48% of respondents. The major sources of support were from colleagues (83%), family (82%) and medical defence organisations (73%), with professional bodies perceived as providing least support. Nearly 80% of respondents felt the need to talk to someone they trust during times of complications. Overall, 100% of respondents used at least one QA tool (62% used two, 26% three and 9% four QA strategies). There were significant differences between respondent groups in use of the QA tools. Conclusions Surgical complications have a significant impact on the well-being of Australian and New Zealand obstetricians and gynaecologists. Existing support comes from colleagues and family, but structured, unbiased support for surgeons from a professional source is urgently warranted.

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Previous research has shown that early maturing girls at age I I have lower subsequent physical activity at age 13 in comparison to later maturing girls. Possible reasons for this association have not been assessed. This study examines girls' psychological response to puberty and their enjoyment of physical activity as intermediary factors linking pubertal maturation and physical activity. Participants included 178 girls who were assessed at age 11, of whom 168 were reassessed at age 13. All participants were non-Hispanic white and resided in the US. Three measures of pubertal development were obtained at age I I including Tanner breast stage, estradiol levels, and mothers' reports of girls' development on the Pubertal Development Scale (PDS). Measures of psychological well-being at ages I I and 13 included depression, global self-worth, perceived athletic competence, maturation fears, and body esteem. At age 13, girls' enjoyment of physical activity was assessed using the Physical Activity Enjoyment Scale and their daily minutes of moderate-to-vigorous physical activity (MVPA) were assessed using objective monitoring. Structural Equation Modeling was used to assess direct and indirect pathways between pubertal development at age I I and MVPA at age 13. In addition to a direct effect of pubertal development on MVPA, indirect effects were found for depression, global self-worth and maturity fears controlling for covariates. In each instance, more advanced pubertal development at age I I was associated with lower psychological wellbeing at age 13, which predicted lower enjoyment of physical activity at age 13 and in turn lower MVPA. Results from this study suggest that programs designed to increase physical activity among adolescent girls should address the self-consciousness and discontent that girls' experience with their bodies during puberty, particularly if they mature earlier than their peers, and identify activities or settings that make differences in body shape less conspicuous.

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Purpose To investigate the effects of a natural oil-based emulsion containing allantoin versus aqueous cream for preventing and managing radiation induced skin reactions (RISR). Methods and Materials A total of 174 patients were randomised and participated in the study. Patients either received Cream 1 (the natural oil-based emulsion containing allantoin) or Cream 2 (aqueous cream). Skin toxicity, pain, itching and skin-related quality of life scores were collected for up to four weeks after radiation treatment. Results Patients who received Cream 1 had a significantly lower average level of Common Toxicity Criteria at week 3 (p<0.05), but had statistically higher average levels of skin toxicity at weeks 7, 8 and 9 (all p<0.001). Similar results were observed when skin toxicity was analysed by grades. With regards to pain, patients in the Cream 2 group had a significantly higher average level of worst pain (p<0.05) and itching (p=0.046) compared to the Cream 1 group at week 3, however these differences were not observed at other weeks. In addition, there was a strong trend for Cream 2 to reduce the incidence of grade 2 or more skin toxicity in comparison to Cream 1 (p=0.056). Overall, more participants in the Cream 1 group were required to use another topical treatment at weeks 8 (p=0.049) and 9 (p=0.01). Conclusion The natural oil-based emulsion containing allantoin appears to have similar effects for managing skin toxicity compared to aqueous cream up to week 5, however, it becomes significantly less effective at later weeks into the radiation treatment and beyond treatment completion (week 6 and beyond). There were no major differences in pain, itching and skin-related quality of life. In light of these results, clinicians and patients can base their decision on costs and preferences. Overall, aqueous cream appears to be a more preferred option.

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The effect of a change of tillage and crop residue management practice on the chemical and micro-biological properties of a cereal-producing red duplex soil was investigated by superimposing each of three management practices (CC: conventional cultivation, stubble burnt, crop conventionally sown; DD: direct-drilling, stubble retained, no cultivation, crop direct-drilled; SI: stubble incorporated with a single cultivation, crop conventionally sown), for a 3-year period on plots previously managed with each of the same three practices for 14 years. A change from DD to CC or SI practice resulted in a significant decline, in the top 0-5 cm of soil, in organic C, total N, electrical conductivity, NH4-N, NO3-N, soil moisture holding capacity, microbial biomass and CO2 respiration as well as a decline in the microbial quotient (the ratio of microbial biomass C to organic C; P <0.05). In contrast, a change from SI to DD or CC practice or a change from CC to DD or SI practice had only negligible impact on soil chemical properties (P >0.05). However, there was a significant increase in microbial biomass and the microbial quotient in the top 0-5 cm of soil following the change from CC to DD or SI practice and with the change from SI to DD practice (P <0.05). Analysis of ester-linked fatty acid methyl esters (EL-FAMEs) extracted from the 0- to 5-cm and 5- to 10-cm layers of the soils of the various treatments detected changes in the FAME profiles following a change in tillage practice. A change from DD practice to SI or CC practice was associated with a significant decline in the ratio of fungal to bacterial fatty acids in the 0- to 5-cm soil (P <0.05). The results show that a change in tillage practice, particularly the cultivation of a previously minimum-tilled (direct-drilled) soil, will result in significant changes in soil chemical and microbiological properties within a 3-year period. They also show that soil microbiological properties are sensitive indicators of a change in tillage practice.

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As the proportion of older employees in the workforce is growing, researchers have become increasingly interested in the association between age and occupational well-being. The curvilinear nature of relationships between age and job satisfaction and between age and emotional exhaustion is well-established in the literature, with employees in their late 20s to early 40s generally reporting lower levels of occupational well-being than younger and older employees. However, the mechanisms underlying these curvilinear relationships are so far not well understood due to a lack of studies testing mediation effects. Based on an integration of role theory and research from the adult development and career literatures, this study examined time pressure, work–home conflict, and coworker support as mediators of the relationships between age and job satisfaction and between age and emotional exhaustion. Data came from 771 employees between 17 and 74 years of age in the construction industry. Results showed that employees in their late 20s to early 40s had lower job satisfaction and higher emotional exhaustion than younger and older employees. Time pressure and coworker support fully mediated both the U-shaped relationship between age and job satisfaction and the inversely U-shaped relationship between age and emotional exhaustion. These findings suggest that organizational interventions may help increase the relatively low levels of occupational well-being in certain age groups.

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This study explored the stress and wellbeing of Emergency Medical Dispatchers (EMD) who remotely provide crisis intervention to medical emergencies through telehealth support. Semi-structured interviews with 16 EMDs were conducted and Interpretative Phenomenological Analysis was used to identify themes in the data. These results indicated that despite their physical distance from the crisis scene, EMDs can experience vicarious trauma through acute and cumulative exposure to traumatic incidents and their perceived lack of control which can expound feelings of helplessness. Three superordinate themes of operational stress and trauma, organisational stress, and posttraumatic growth were identified. Practical implications are suggested to enable emergency services organisations to counteract this job related stress and promote more positive mental health outcomes.

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The purpose of this article is to explain why the first year in higher education experience of Australian tertiary students can be improved through the explicit teaching of independent learning skills. Becoming an independent learner has many benefits, but the focus of this piece is upon the connection between independent learning and the improvement of student psychological well-being. High psychological distress levels appear to start in the first year of university education. We argue that explicitly teaching students independent learning skills is an important curriculum-based strategy that will contribute to the significant task of addressing this issue.

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Random blinking is a major problem on the way to successful applications of semiconducting nanocrystals in optoelectronics and photonics, which until recently had neither a practical solution nor a theoretical interpretation. An experimental breakthrough has recently been made by fabricating non-blinking Cd1-xZnxSe/ZnSe graded nanocrystals [Wang et al., Nature, 2009, 459, 686]. Here, we (1) report an unequivocal and detailed theoretical investigation to understand the properties (e.g., profile) of the potential-well and the distribution of Zn content with respect to the nanocrystal radius and (2) develop a strategy to find the relationship between the photoluminescence (PL) energy peaks and the potential-well due to Zn distribution in nanocrystals. It is demonstrated that the non-square-well potential can be varied in such a way that one can indeed control the PL intensity and the energy-level difference (PL energy peaks) accurately. This implies that one can either suppress the blinking altogether, or alternatively, manipulate the PL energy peaks and intensities systematically to achieve a controlled non-random intermittent luminescence. The approach developed here is based on the ionization energy approximation and as such is generic and can be applied to any non-free-electron nanocrystals.