996 resultados para Dione Hutchinson


Relevância:

10.00% 10.00%

Publicador:

Resumo:

Single pass warm rolling and compression experiments were carried out from ambient to 800°C for ultra-low carbon (ULC) steel with ∼100 ppm carbon and interstitial free (IF) steels, both with two levels of silicon. Subsequently, annealing was done in order to recrystallize the deformed specimens. The main purpose of this study was to understand the effects of rolling temperature and silicon on stress responses and textures. This study comprises two main themes: flow stress and strain rate sensitivity during compression and shear banding and textures in warm rolled specimens. The effects of deformation temperature on in-grain shear bands were different between ULC-Si and IF-Si steels. As in previous work with more conventional steels, in-grain shear bands in the IF grade had low sensitivity to rolling temperature, while those in the ULC grade depended significantly on the deformation temperature. However, the temperature profile of shear banding in the ULC grade was approximately 150°C higher than in previous work. Deformation and recrystallisation textures for both IF and ULC grades depended on their rolling temperatures. The variation of both grain size and texture after annealing can be explained by the rise and fall of in-grain shear banding activity which is related to the strain rate sensitivity.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Although martensite is recognised as a very strong phase in carbon steels, its initial yielding commences at low stresses and the tensile stress-strain curve shows a smooth, rounded form. Evidence is presented from x-ray diffraction to show that this behaviour is due to the presence of intra-granular stresses that are residues after the shear transformation from austenite to martensite. These internal stresses are reduced in magnitude by plastic deformation and also by tempering. Reduction of internal stress due to plasticity is shown by a decrease in XRD line broadening after deformation. A simple model is presented in which the stress-strain behaviour is controlled by relaxation of the internal stresses almost up to the point of the ultimate tensile strength. It demonstrates that only a very small fraction of the material remaining in a purely elastic state provides a large stabilising effect resisting necking. A corollary of this is that the uniform elongation of martensitic steel actually increases with increase in the strength level. Effects of heat treatment are also reproduced in the model, including the increase in conventional yield stress (Rp0.2) that occurs after low temperature tempering.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Supply chain management (SCM) is increasingly dependent on electronic systems. At the same time, the vulnerability of these systems to attack from malicious individuals or groups is growing. This paper examines some of the forms such attacks can take, and their relevance to the supply function. Provides examples of attacks. Concludes that companies should consider the security aspects of electronic commerce before developing their systems. © MCB University Press.

Relevância:

10.00% 10.00%

Publicador:

Relevância:

10.00% 10.00%

Publicador:

Resumo:

ABSTRACT
This paper addresses the strain ageing effects on the mechanical properties of the partially damaged structural mild steel. Since repairing partly damaged structures may not occur immediately, the strain ageing effect can significantly influence the structural behaviour. The changes due to this effect have not so far been considered in the civil engineering design guidelines. In order to investigate strain ageing effects, two-stage experimental tests are carried out on the mild-steel specimens. In the first stage, partial damage is made using quasi-static loading. During the second stage, the strength and ductility of the specimens are examined after 2 and 7 days ‘ageing’ at room temperature and the results are compared with the corresponding no-age samples. The microstructure of the specimens is examined using scanning electron microscopy (SEM). To illustrate the effect of strain ageing on the global behaviour of steel structures, a numerical example is provided in which strain ageing impacts on loading capacity and deflection of a steel beam. Finally, the stress–strain relation of partially damaged mild-steel material incorporating strain ageing effects is expressed by calibrating the parameters of Ramberg–Osgood model.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

BACKGROUND: The relative contributions of cannabis and alcohol use to educational outcomes are unclear. We examined the extent to which adolescent cannabis or alcohol use predicts educational attainment in emerging adulthood. METHODS: Participant-level data were integrated from three longitudinal studies from Australia and New Zealand (Australian Temperament Project, Christchurch Health and Development Study, and Victorian Adolescent Health Cohort Study). The number of participants varied by analysis (N=2179-3678) and were assessed on multiple occasions between ages 13 and 25. We described the association between frequency of cannabis or alcohol use prior to age 17 and high school non-completion, university non-enrolment, and degree non-attainment by age 25. Two other measures of alcohol use in adolescence were also examined. RESULTS: After covariate adjustment using a propensity score approach, adolescent cannabis use (weekly+) was associated with 1½ to two-fold increases in the odds of high school non-completion (OR=1.60, 95% CI=1.09-2.35), university non-enrolment (OR=1.51, 95% CI=1.06-2.13), and degree non-attainment (OR=1.96, 95% CI=1.36-2.81). In contrast, adjusted associations for all measures of adolescent alcohol use were inconsistent and weaker. Attributable risk estimates indicated adolescent cannabis use accounted for a greater proportion of the overall rate of non-progression with formal education than adolescent alcohol use. CONCLUSIONS: Findings are important to the debate about the relative harms of cannabis and alcohol use. Adolescent cannabis use is a better marker of lower educational attainment than adolescent alcohol use and identifies an important target population for preventive intervention.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Abstract
The transition from adolescence to young adulthood is a watershed period in development that carries risk for poor psychosocial adjustment. It also carries potential for positive transitions into the caregiving roles and responsibilities of adult life. Research to date has predominantly focused on adolescent predictors of problematic rather than positive transitions; yet predictors of the latter hold equal (if not greater) promise for informing health promoting interventions. The purpose of this study was threefold: (1) to use Latent Profile Analysis (LPA) to define patterns of psychosocial adjustment and maladjustment in young adulthood (21-years of age); (2) to examine the unique role of adolescent prosocial behaviour (e.g., volunteering and civic engagement) in promoting adjustment and reducing maladjustment in young adulthood; and, (3) to examine whether protective developmental relationships are maintained after adjustment for other covariates including socio-economic background factors and personality characteristics. Data were drawn from the Victorian cohort of the International Youth Development Study (IYDS; N = 2407), a representative sample of students in Victoria, Australia. Students were assessed in Grade 9 (Mean age = 15-years) and followed up at age 21-years. LPA identified three psychosocial adjustment classes at age 21 defined as: (1) Adjusted (24.8 %); (2) Normative (63.9 %); and, (3) Maladjusted (11.3 %). Adolescent volunteering, belief in a moral order, family opportunities for prosocial behaviour, and commitment to school were associated with enhanced adjustment and reduced maladjustment in young adulthood. Findings highlight the potential benefit of interventions designed to enhance adolescent prosocial behaviours and care orientation in promoting healthy transitions into young adult life.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Using a sample of 2,200 U.S. listed firm-year observations (2001-2007), this study shows a positive (negative) relation between gender diversity on corporate boards and analysts' earnings forecast accuracy (dispersion), after controlling for earnings quality, corporate governance, audit quality, stock price informativeness, and potential endogeneity. Our findings are important as they suggest that board diversity adds to the transparency and accuracy of financial reports such that earnings expectations are likely to be more accurate for these firms.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

BACKGROUND: Health professionals need to be integrated more effectively in clinical research to ensure that research addresses clinical needs and provides practical solutions at the coal face of care. In light of limited evidence on how best to achieve this, evaluation of strategies to introduce, adapt and sustain evidence-based practices across different populations and settings is required. This project aims to address this gap through the co-design, development, implementation, evaluation, refinement and ultimately scale-up of a clinical research engagement and leadership capacity building program in a clinical setting with little to no co-ordinated approach to clinical research engagement and education.

METHODS/DESIGN: The protocol is based on principles of research capacity building and on a six-step framework, which have previously led to successful implementation and long-term sustainability. A mixed methods study design will be used. Methods will include: (1) a review of the literature about strategies that engage health professionals in research through capacity building and/or education in research methods; (2) a review of existing local research education and support elements; (3) a needs assessment in the local clinical setting, including an online cross-sectional survey and semi-structured interviews; (4) co-design and development of an educational and support program; (5) implementation of the program in the clinical environment; and (6) pre- and post-implementation evaluation and ultimately program scale-up. The evaluation focuses on research activity and knowledge, attitudes and preferences about clinical research, evidence-based practice and leadership and post implementation, about their satisfaction with the program. The investigators will evaluate the feasibility and effect of the program according to capacity building measures and will revise where appropriate prior to scale-up.

DISCUSSION: It is anticipated that this clinical research engagement and leadership capacity building program will enable and enhance clinically relevant research to be led and conducted by health professionals in the health setting. This approach will also encourage identification of areas of clinical uncertainty and need that can be addressed through clinical research within the health setting.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

AIM: Existing practice strategies for actively involving patients in care during hospitalisation are poorly understood. The aim of this study was to explore how healthcare professionals engaged patients in communication associated with care transitions.

METHOD: An instrumental, collective case study approach was used to generate empirical data about patient transitions in care. A purposive sample of key stakeholders representing (i) patients and their families; (ii) hospital discharge planning team members; and (iii) healthcare professionals was recruited in five Australian health services. Individual and group semi-structured interviews were conducted to elicit detailed explanations of patient engagement in transition planning. Interviews lasted between 30 and 60 minutes and were digitally recorded and transcribed verbatim. Data collection and analysis were conducted simultaneously and continued until saturation was achieved. Thematic analysis was undertaken.

RESULTS: Five themes emerged as follows: (i) organisational commitment to patient engagement; (ii) the influence of hierarchical culture and professional norms on patient engagement; (iii) condoning individual healthcare professionals' orientations and actions; (iv) understanding and negotiating patient preferences; and (v) enacting information sharing and communication strategies. Most themes illustrated how patient engagement was enabled; however, barriers also existed.

CONCLUSION: Our findings show that strong organisational and professional commitment to patient-centred care throughout the organisation was a consistent feature of health services that actively engaged patients in clinical communication. Understanding patients' needs and preferences and having both formal and informal strategies to engage patients in clinical communication were important in how this involvement occurred.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

AIM: To describe an integrative review protocol to analyse and synthesize peer-reviewed research evidence in relation to engagement of patients and their families in communication during transitions of care to, in and from acute care settings.

BACKGROUND: Communication at transitions of care in acute care settings can be complex and challenging, with important information about patients not always clearly transferred between responsible healthcare providers. Involving patients and their families in communication during transitions of care may improve the transfer of clinical information and patient outcomes and prevent adverse events during hospitalization and following discharge. Recently, optimizing patient and family participation during care transitions has been acknowledged as central to the implementation of patient-centred care.

DESIGN: Integrative review with potential for meta-analysis and application of framework synthesis.

REVIEW METHOD: The review will evaluate and synthesize qualitative and quantitative research evidence identified through a systematic search. Primary studies will be selected according to inclusion criteria. Data collection, quality appraisal and analysis of the evidence will be conducted by at least two authors. Nine electronic databases (including CINAHL and Medline) will be searched. The search will be restricted to 10 years up to December 2013. Data analysis will include content and thematic analysis.

DISCUSSION: The review will seek to identify all types of patient engagement activities employed during transitions of care communication. The review will identify enablers for and barriers to engagement for patients, families and health professionals. Key strategies and tools for improving patient engagement, clinical communication and promoting patient-centred care will be recommended based on findings.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

BACKGROUND: Clinical decision-making is a complex activity that is critical to patient safety. Simulation, augmented by feedback, affords learners the opportunity to learn critical clinical decision-making skills. More detailed feedback following simulation exercises has the potential to further enhance student learning, particularly in relation to developing improved clinical decision-making skills. OBJECTIVE: To investigate the feasibility of head-mounted video camera recordings, to augment feedback, following acute patient deterioration simulations. DESIGN: Pilot study using an observational design. METHODS: Ten final-year nursing students participated in three simulation exercises, each focussed on detection and management of patient deterioration. Two observers collected behavioural data using an adapted version of Gaba's Clinical Simulation Tool, to provide verbal feedback to each participant, following each simulation exercise. Participants wore a head-mounted video camera during the second simulation exercise only. Video recordings were replayed to participants to augment feedback, following the second simulation exercise. Data were collected on: participant performance (observed and perceived); participant perceptions of feedback methods; and head-mounted video camera recording feasibility and capability for detailed audio-visual feedback. RESULTS: Management of patient deterioration improved for six participants (60%). Increased perceptions of confidence (70%) and competence (80%), were reported by the majority of participants. Few participants (20%) agreed that the video recording specifically enhanced their learning. The visual field of the head-mounted video camera was not always synchronised with the participant's field of vision, thus affecting the usefulness of some recordings. CONCLUSION: The usefulness of the video recordings, to enhance verbal feedback to participants on detection and management of simulated patient deterioration, was inconclusive. Modification of the video camera glasses, to improve visual-field synchronisation with participants' actual visual field, is recommended to further explore this technology for enhancing student performance.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

The Pinoke Project is a 6 week creative development to create a full-length transmedia dance performance at the cutting edge of artificially intelligent technology, elite contemporary dance practice, and publication. This process will be a collaboration between creative coders, 3D graphics and motion artists, a dance/choreographer, and an embedded dance critic who will work with an artificially intelligent robot, Pinoke, on the creative development of a new stage production as well as the documentation and dissemination of the process. This project is supported by the Victorian Government through Creative Victoria.