1,636 research outputs found
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Unidisciplinary CPD in a multidisciplinary world: Experiences from practice
Continuing professional development (CPD) has become relevant to all healthcare staff as professional bodies develop processes to revalidate and renew registration based on evidence of lifelong learning and CPD. As a result, the number of practice and professional development groups such as journal clubs, is increasing. Little evidence is available to differentiate between unidisciplinary and multidisciplinary CPD group activities, although by anecdotal reports, the number of unidisciplinary CPD groups appears to be growing. This study aimed to evaluate the value of a unidisciplinary occupational therapy CPD group to its six participants, the multidisciplinary teams in which they worked, and for the service users referred to them. A qualitative approach from a phenomenological perspective was used to explore this previously under-researched area. Triangulation of the data was achieved using postal questionnaires with open questions, the service manager as key informant and a research diary. Four main themes emerged from the inductive analysis: critical evaluation of practice to improve service delivery, improving communication for mutual learning, developing as a discipline with the multi-disciplinary team, and developing clinical skills. The implications of the study both for this uniprofessional group as well as for the multidisciplinary teams in which the occupational therapists worked are discussed, with recommendations made for future practice
Massive Star Evolution: Nucleosynthesis and Nuclear Reaction Rate Uncertainties
We present a nucleosynthesis calculation of a 25 solar mass star of solar
composition that includes all relevant isotopes up to polonium. In particular,
all stable isotopes and necessary nuclear reaction rates are covered. We follow
the stellar evolution from hydrogen burning till iron core collapse and
simulate the explosion using a ``piston'' approach. We discuss the influence of
two key nuclear reaction rates, C12(a,g) and Ne22(a,n), on stellar evolution
and nucleosynthesis. The former significantly influences the resulting core
sizes (iron, silicon, oxygen) and the overall presupernova structure of the
star. It thus has significant consequences for the supernova explosion itself
and the compact remnant formed. The later rate considerably affects the
s-process in massive stars and we demonstrate the changes that different
currently suggested values for this rate cause.Comment: 6 pages, including 4 PostScript figures, to appear in Proc.
"Astronomy with Radioactivities III", New Astronomy Review
Structured review of the patient-reported outcome instruments used in clinical trials in head and neck surgery
The number of clinical trials that relate to patients with cancer of the head and neck is growing. Patient-reported outcomes, which are rarely the primary outcome, are now an important component, and in this structured review to identify and report the characteristics of the questionnaires that have been used in these trials, we summarise the findings reported. We searched several online databases using the key terms: head and neck oncology, head and neck surgery, reconstruction, clinical trials patient-reported outcomes, questionnaires, quality of life (QoL), validated instruments, and patients’ satisfaction. We screened 1342 papers to collect information about the topic of the paper, sample size, selection criteria, main advantages and disadvantages of the patient-reported outcome used, and if it was used in conjunction with another measure. A total of 54 were eligible, and from them we identified 22 questionnaires. The primary reason for using a questionnaire was its relevance to the focus of the paper, such as xerostomia, pain, or swallowing. To allow the experience of patients to be the focus of the primary outcome in a clinical trial, we recommend that the measures used should be appropriate, reliable, valid, responsive, precise, interpretable, acceptable, and feasible. The trials used validated questionnaires, but the patient-reported outcome measures tended not to be the focus. There is merit in such measures being the primary outcomes in future trials and these should be designed around an explicit hypothesis
Self-concept in poor readers : A systematic review and meta-analysis
Background
The aims of this systematic review and meta-analyses were to determine if there is a statistically reliable association between poor reading and poor self-concept, and if such an association is moderated by domain of self-concept, type of reading impairment, or contextual factors including age, gender, reading instruction, and school environment.
Methodology
We searched 10 key databases for published and unpublished studies, as well as reference lists of included studies, and studies that cited included studies. We calculated standardised mean differences (SMDs) and 95% confidence intervals for one primary outcome (average self-concept) and 10 secondary outcomes (10 domains of self-concept). We assessed the data for risk of bias, heterogeneity, sensitivity, reporting bias, and quality of evidence.
Results
Thirteen studies with 3,348 participants met our selection criteria. Meta-analyses revealed statistically significant SMDs for average self-concept (−0.57) and five domains of self-concept (reading/writing/spelling: −1.03; academic: −0.67; math: −0.64; behaviour: −0.32; physical appearance: −0.28). The quality of evidence for the primary outcome was moderate, and for secondary outcomes was low, due to lack of data.
Conclusions
These outcomes suggest a probable moderate association between poor reading and average self-concept; a possible strong association between poor reading and reading-writing-spelling self-concept; and possible moderate associations between poor reading and self-concept in the self-concept domains of academia, mathematics, behaviour, and physical appearance
Enantioselective synthesis using bromoacetals.
A brief overview of why it is important to prepare a chiral compound as a specific enantiomer rather than as a racemate is discussed along with several general strategies on how they maybe prepared. The area of research into the preparation of racemic and enantiomerically pure arylpropanoic acids is briefly reviewed by reference to some of the more important synthons. Some of the more general procedures that have been developed for the construction of arylpropanoic acids are discussed. The preparation of substituted alkyl aryl ketones and their subsequent two step conversion into diastereomerically enriched dimethyl tartrate (S)-bromoalkyl aryl acetals is described. An investigation into the effects of solvent, source of anhydrous acid, workup procedure, source of bromine and temperature upon the bromination of these dimethyl tartrate acetals is discussed. Direct conversion of these diastereomerically enriched dimethyl tartrate (S)-bromoalkyl aryl acetals into enantiomerically pure (S)-bromoalkyl aryl ketones and their subsequent conversion into (S)-bromoalkyl aryl esters via a Baeyer-Villiger reaction is described. Hydrolysis of these (S)-bromoalkyl aryl esters followed by treatment with diazomethane afforded the corresponding methyl (S)-bromoalkyl esters with minimal racemisation, while treatment of these (S)-bromoalkyl aryl esters with an amine gave the corresponding amide with minimal racemisation. Reduction with sodium borohydride at low temperature of a (S)-bromoalkyl aryl ketone afforded exclusively the corresponding (1S,2S) alkyl aryl bromohydrin as predicted using the Felkin-Anh model. Stereospecific conversion of our diastereomerically enriched dimethyl tartrate (S)-bromoalkyl aryl acetals into (S)-arylcarboxylic acids using a silver promoted or solvent promoted rearrangement is discussed. Subsequent conversion of these (S)-arylcarboxylic acids into the corresponding Boc amide via a modified Curtius rearrangement is described.Possible further uses of dimethyl tartrate bromoacetals leading to the synthesis of highly functionalised lactones, lactols, epoxides, chiral diacids, diamines, chiral ligands, resolving agents etc are also discussed
High Temperature Brush Seal Tuft Testing of Selected Nickel-Chrome and Cobalt-Chrome Superalloys
The tribology of brush seals is of considerable interest to turbine engine designers because bristle wear continues to limit long term seal performance and life. To provide better materials characterization and foster the development of improved seals, NASA Lewis has developed a brush seal tuft tester. In this test, a 'paintbrush' sample tuft is loaded under constant contact pressure against the outside diameter of a rotating journal. With this configuration, load and friction are directly measured and accurate wear measurements are possible. Previously reported research using this facility showed excellent data repeatability and wear morphology similar to published seal data and dynamic rig tests. This paper is an update of the ongoing research into the tribology of brush seals. The effects of wire materials processing on seal wear and the tribological results for three journal coatings are discussed. Included in the materials processing were two nickel-chrome superalloys each processed to two different yield strengths. The results suggest that seal wear is dependent more on material composition than processing conditions
High temperature brush seal tuft testing of metallic bristles versus chrome carbide
The tribology of brush seals is of considerable interest to turbine engine designers because bristle wear continues to limit long term seal performance and life. To provide better materials characterization and foster the development of improved seals, NASA Lewis has developed a brush seal tuft tester. In this test, a 'paintbrush' sample tuft is loaded under constant contact pressure against the outside diameter of a rotating journal. With this configuration a direct measurement of load and friction is made. Accurate wear rate measurements are possible due to the known contact pressure. Previously reported baseline research using this facility showed good data repeatability and wear morphology similar to published seal data. This paper extends and expands the database for candidate brush seal materials. A series of tuft tests were completed to evaluate the performance of five high temperature superalloy wires sliding against plasma sprayed nichrome-bonded chrome carbide. Wire materials were either nickel-chrome or cobalt-chrome based superalloys. Good corroboration of the tuft results with dynamic seal rig tests was observed; giving additional confidence in the tuft test as a screening and development tool
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