Coatings decrease metal fatigue failure

Metal test specimens were coated with suitable materials to limit the rate of attack of fresh metal surfaces by the atmosphere. The fatigue properties of coated metals were superior to those which were uncoated and approached the properties observable in vacuum

Effects of moisture on torsion and flexure properties of graphite-epoxy composites

The effects of moisture and temperature on unidirectional and multi-ply laminates of T300/934 and AS/3501 graphite-epoxy systems were investigated. Properties studied were static flexure strength, and flexure and torsion fatigue strengths at room temperature and at 74 C. Specimens with increased moisture content showed a reduced static flexure strength; water as the test environment had only a negligible influence. In flexure fatigue and torsion fatigue, the water environment caused somewhat reduced fatigue strengths at room temperature and significantly greater degradation in 74 C water. The failure mode in all cases was interlaminar delamination

Simple torsion test for shear moduli determination of orthotropic composites

By means of torsion tests performed on test specimens of the same material having a minimum of two different cross sections (flat sheet of different widths), the effective in-plane (G13) and out-of-plane (G23) shear moduli were determined for two composite materials of uniaxial and angleply fiber orientations. Test specimens were 16 plies (nominal 2 mm) thick, 100 mm in length, and in widths of 6.3, 9.5, 12.5, and 15.8 mm. Torsion tests were run under controlled deflection (constant angle of twist) using an electrohydraulic servocontrolled test system. In-plane and out-of-plane shear moduli were calculated from an equation derived in the theory of elasticity which relates applied torque, the torsional angle of twist, the specimen width/thickness ratio, and the ratio of the two shear moduli G13/G23. Results demonstrate that torsional shear moduli, G23 as well as G13, can be determined by simple torsion tests of flat specimens of rectangular cross section. Neither the uniaxial nor angleply composite material were transversely isotropic

Environmental Effects on Graphite-Epoxy Fatigue Properties

Effects of torsional and flexural fatigue on the long-time Integrity of advanced graphite-epoxy structural composites have been investigated. Torsional fatigue tests were run at stress ratios of R = 0 (zero to maximum, repeated) and R = -1 (zero mean stress) on unidirectional, angleply, and woven graphite fiber materials in air and water at room temperature and at 74 C. Flexural fatigue tests (four-point bending) with R = -1 were run in air and water at room temperature, and with R = 0 in air. Results show that, in torsional cycling, both water environment and higher test temperature contribute to significant degradation of torsional stiffness. The degradation of stiffness from torsional stress cycling was observed to be much greater with R = -1 than with simple R = 0 cycling. The effect of environment also is greater in the fully reversed cycling. Flexural fatigue results on +/- 30 deg material show a large fatigue effect, with fatigue limits of less than 50% and 30% of the static failure strength for specimens tested under stress ratios of R = 0 and R = -1, respectively. Compliance measurements indicate that the final failures are preceded by damage initiation and accumulation, which begins at about 1% of the specimen life

Aluminum Canning of Nickel-Plated, Hanford Four-Inch Uranium Fuel Slugs by Hot-Pressing

Conditions of time, temperature, and pressure for hotpress bonding of aluminum-nickel and uranium-nickel disks were determined experimentally. A process for jacketing Hanford four-inch slugs, coated with nonporous nickel electroplates, in aluminum cans by cold-sizing and hot-pressing was developed and conditions of time, temperature, and pressure required for the actual canning process were determined. (auth

Co-constructing desired activities : Small-scale activity decisions in occupational therapy

Social inclusion and exclusion are buzzwords in today’s political discourse. While there are many causes of social exclusion, one of the factors repeatedly shown to lead to social exclusion is mental illness, which may hinder people in developing themselves in accordance with their wishes and abilities. Participation is a key dimension of social inclusion—and one that we particularly seek to increase understanding of in this volume. We focus on participation taking place in face-to-face social encounters, seeking to get to the root of the preconditions and consequences of participation by unraveling the interactional processes that underlie what makes it possible. We presuppose that participation in any social or societal sphere presupposes social interaction, which in turn requires the capacity to coordinate with and make sense of others’ actions. Thus, drawing on joint decision-making as a specific arena of social interaction, where the participants’ collaborative management of the turn-by-turn sequential unfolding of interaction can have tangible consequences for the participants’ social and economic circumstances, we seek to increase understanding of the specific vulnerabilities that individuals with mental illness have in this context.In occupational therapy, a therapist and client engage in shared activities that they perform collaboratively during therapeutic sessions. An important part of this joint performance involves providing the client with the opportunity to make short-term decisions on the activities they wish to perform. Analyzing 15 occupational therapy encounters at psychiatric outpatient clinics, in the chapter I explore the functions of these small-scale decisions. The analysis demonstrates that therapists (1) make room for the client’s proposals by shaping the activity context and (2) make proposals themselves on the ways the performance should be accomplished. To summarize, clients are given decision-making power over the content of the activity, whereas therapists use their decision-making power to assist the client’s performance. The analysis shows how small-scale decisions can be employed to construct the occupational performance as shared endeavors and to position the clients as active subjects rather than objects of the professionals’ performance.Peer reviewe

What are the important components of the clinical assessment of hand problems in older adults in primary care? Results of a Delphi study

<p>Abstract</p> <p>Background</p> <p>To identify clinical questions and assessments regarded by health care practitioners as important when assessing undifferentiated hand pain or problems in adults aged 50 years and over presenting to primary care.</p> <p>Methods</p> <p>A purposively selected panel of 26 UK-based Health Care Practitioners comprising occupational therapists, physiotherapists, rheumatologists and general practitioners, were invited to take part in a consensus study involving three postal rounds of a Delphi questionnaire with accompanying case scenarios. Participants were asked to generate questions and assessments (round 1), rate their importance (round 2), and vote on which items were most important (round 3).</p> <p>Results</p> <p>Sixteen Health Care Practitioners agreed to participate with 11 completing all three rounds. The first round of the Delphi study generated 156 questions and 143 assessments. After three rounds agreement was reached on the importance of 25 questions and 19 assessments. Questions were weighted towards current symptoms, but also included the history of previous hand problems, self-reported hand function, co-morbidity and general health. Observation and palpation of features predominated in the choice of assessment, but specific tests, grip strength, evaluation of sensation and hand function were also included.</p> <p>Conclusions</p> <p>A pool of clinical questions and assessments were generated by Health Care Practitioners, and those considered most important for assessing older adults presenting with undifferentiated hand pain and hand problems in primary care were identified. Further evaluation is required to establish the reliability and feasibility of using these questions and assessments in primary care. In particular, the relative contribution of these questions and assessments in evaluating the nature and severity of hand problems, assisting diagnosis, indicating appropriate management, and predicting future course requires further investigation.</p

Teacher quality in the twenty first century: new lives, old truths

This chapter is based upon a keynote address to the first global teacher education summit, organised by Beijing Normal University in 2011, in which research across the world about influences which affect teachers' sense of professional identity, capacity for compassion, commitment, resilience and effectiveness long after they have graduated from their pre-service education and training programmes in universities and colleges were shared. The findings suggest that teaching pre-service students about how the conditions in which they work may enhance or diminish their capacity to teach to their best and how they might act to mediate these is a key part of the work of all teacher educators and an important focus for the work of educational researchers

A modified Delphi study of screening for fetal alcohol spectrum disorders in Australia

Background: There is little reliable information on the prevalence of fetal alcohol spectrum disorders (FASD) in Australia and no coordinated national approach to facilitate case detection. The aim of this study was to identify health professionals’ perceptions about screening for FASD in Australia. Method: A modified Delphi process was used to assess perceptions of the need for, and the process of, screening for FASD in Australia. We recruited a panel of 130 Australian health professionals with experience or expertise in FASD screening or diagnosis. A systematic review of the literature was used to develop Likert statements on screening coverage, components and assessment methods which were administered using an online survey over two survey rounds. Results: Of the panel members surveyed, 95 (73%) responded to the questions on screening in the first survey round and, of these, 81 (85%) responded to the second round. Following two rounds there was consensus agreement on the need for targeted screening at birth (76%) and in childhood (84%). Participants did not reach consensus agreement on the need for universal screening at birth (55%) or in childhood (40%). Support for targeted screening was linked to perceived constraints on service provision and the need to examine the performance, costs and benefits of screening. For targeted screening of high risk groups, we found highest agreement for siblings of known cases of FASD (96%) and children of mothers attending alcohol treatment services (93%). Participants agreed that screening for FASD primarily requires assessment of prenatal alcohol exposure at birth (86%) and in childhood (88%), and that a checklist is needed to identify the components of screening and criteria for referral at birth (84%) and in childhood (90%). Conclusions: There is an agreed need for targeted but not universal screening for FASD in Australia, and sufficient consensus among health professionals to warrant development and evaluation of standardised methods for targeted screening and referral in the Australian context. Participants emphasised the need for locally-appropriate, evidence-based approaches to facilitate case detection, and the importance of ensuring that screening and referral programs are supported by adequate diagnostic and management capacity

Fetal alcohol spectrum disorder: development of concensus referral criteria for specialist diagnostic assessment in Australia

Background: Fetal alcohol spectrum disorder (FASD) is known to be under-recognised in Australia. The use of standard methods to identify when to refer individuals who may have FASD for specialist assessment could help improve the identification of this disorder. The purpose of this study was to develop referral criteria for use in Australia. Method: An online survey about FASD screening and diagnosis in Australia, which included 23 statements describing criteria for referral for fetal alcohol syndrome (FAS) and FASD based on published recommendations for referral in North America, was sent to 139 health professionals who had expertise or involvement in FASD screening or diagnosis. Survey findings and published criteria for referral were subsequently reviewed by a panel of 14 investigators at a consensus development workshop where criteria for referral were developed.Results: Among the 139 health professionals who were sent the survey, 103 (74%) responded, and 90 (65%) responded to the statements on criteria for referral. Over 80% of respondents agreed that referral for specialist evaluation should occur when there is evidence of significant prenatal alcohol exposure, defined as 7 or more standard drinks per week and at least 3 standard drinks on any one day, and more than 70% agreed with 13 of the16 statements that described criteria for referral other than prenatal alcohol exposure. Workshop participants recommended five independent criteria for referral: confirmed significant prenatal alcohol exposure; microcephaly and confirmed prenatal alcohol exposure; 2 or more significant central nervous system (CNS) abnormalities and confirmed prenatal alcohol exposure; 3 characteristic FAS facial anomalies; and 1 characteristic FAS facial anomaly, growth deficit and 1 or more CNS abnormalities .Conclusion: Referral criteria recommended for use in Australia are similar to those recommended in North America. There is a need to develop resources to raise awareness of these criteria among health professionals and evaluate their feasibility, acceptability and capacity to improve the identification of FASD in Australia