242 research outputs found
Trust Based Participant Driven Privacy Control in Participatory Sensing
Widespread use of sensors and multisensory personal devices generate a lot of
personal information. Sharing this information with others could help in
various ways. However, this information may be misused when shared with all.
Sharing of information between trusted parties overcomes this problem. This
paper describes a model to share information based on interactions and opinions
to build trust among peers. It also considers institutional and other controls,
which influence the behaviour of the peers. The trust and control build
confidence. The computed confidence bespeaks whether to reveal information or
not thereby increasing trusted cooperation among peers.Comment: 14 page
Development of HVOF Sprayed Erosion/Oxidation Resistant Coatings for Composite Structural Components in Propulsion Systems
Thermally sprayed coatings are being studied and developed as methods of enabling lightweight composites to be used more extensively as structural components in propulsion applications in order to reduce costs and improve efficiency through weight reductions. The primary goal of this work is the development of functionally graded material [FGM] polymer/metal matrix composite coatings to provide improved erosion/oxidation resistance to polyimide-based polymer matrix composite [PMC] substrates. The goal is to grade the coating composition from pure polyimide, similar to the PMC substrate matrix on one side, to 100% WC-Co on the other. Both step-wise and continuous gradation of the loading of the WC-Co reinforcing phase are being investigated, Details of the coating parameter development will be presented, specifically the high velocity oxy-fuel [HVOF] combustion spraying of pure PMR-I1 matrix material and layers of various composition PMR-II/WC-Co blends onto steel and PMR-15 composite substrates. Results of the HVOF process optimization, microstructural characterization, and analysis will be presented. The sprayed coatings were evaluated using standard metallographic techniques - optical and scanning electron microscopy [SEMI. An SEM + electron dispersive spectroscopy [EDS] technique has also been used to confirm retention of the PMR-I1 component. Results of peel/butt adhesion testing to determine adhesion will also be presented
The impact of CACNA1C gene, and its epistasis with ZNF804A, on white matter microstructure in health, schizophrenia and bipolar disorder
Genome-wide studies have identified allele A (adenine) of single nucleotide polymorphism (SNP) rs1006737 of the calcium-channel CACNA1C gene as a risk factor for both schizophrenia (SZ) and bipolar disorder (BD) as well as allele A for rs1344706 in the zinc-finger ZNF804A gene. These illnesses have also been associated with white matter abnormalities, reflected by reductions in fractional anisotropy (FA), measured using diffusion tensor imaging (DTI). We assessed the impact of the CACNA1C psychosis risk variant on FA in SZ, BD and health. 230 individuals (with existing ZNF804A rs1344706 genotype data) were genotyped for CACNA1C rs1006737 and underwent DTI. FA data was analysed with tract-based spatial statistics and threshold-free cluster enhancement significance correction (p < 0.05) to detect effects of CACNA1C genotype on FA, and its potential interaction with ZNF804A genotype and with diagnosis, on FA. There was no significant main effect of the CACNA1C genotype on FA, nor diagnosis by genotype(s) interactions. Nevertheless, when inspecting SZ in particular, risk allele carriers had significantly lower FA than the protective genotype individuals, in portions of the left middle occipital and parahippocampal gyri, right cerebelleum, left optic radiation and left inferior and superior temporal gyri. Our data suggests a minor involvement of CACNA1C rs1006737 in psychosis via conferring susceptibility to white matter microstructural abnormalities in SZ. Put in perspective, ZNF804A rs1344706, not only had a significant main effect, but its SZ-specific effects were two orders of magnitude more widespread than that of CACNA1C rs1006737
Stereodivergent Synthesis of Enantioenriched 4-Hydroxy-2- cyclopentenones
Protected 4-hydroxycyclopentenones (4-HCPs) constitute an important class of intermediates in chemical synthesis. A route to this class of compound has been developed. Key steps include Noyori reduction (which establishes the stereochemistry of the product), ring-closing metathesis, and simple functional group conversions to provide a set of substituted 4-HCPs in either enantiomeric form
Highly Water-Stable Zirconium Metal-Organic Framework UiO-66 Membranes Supported on Alumina Hollow Fibers for Desalination
In this study, continuous zirconium(IV)-based metal-organic framework (Zr-MOF) membranes were prepared. The pure-phase Zr-MOF (i.e., UiO-66) polycrystalline membranes were fabricated on alumina hollow fibers using an in situ solvothermal synthesis method. Single-gas permeation and ion rejection tests were carried out to confirm membrane integrity and functionality. The membrane exhibited excellent multivalent ion rejection (e.g., 86.3% for Ca2+, 98.0% for Mg2+, and 99.3% for Al3+) on the basis of size exclusion with moderate permeance (0.14 L m-2 h-1 bar-1) and good permeability (0.28 L m-2 h-1 bar-1 μm). Benefiting from the exceptional chemical stability of the UiO-66 material, no degradation of membrane performance was observed for various tests up to 170 h toward a wide range of saline solutions. The high separation performance combined with its outstanding water stability suggests the developed UiO-66 membrane as a promising candidate for water desalination
Exploring UK medical school differences: the MedDifs study of selection, teaching, student and F1 perceptions, postgraduate outcomes and fitness to practise
BACKGROUND: Medical schools differ, particularly in their teaching, but it is unclear whether such differences matter, although influential claims are often made. The Medical School Differences (MedDifs) study brings together a wide range of measures of UK medical schools, including postgraduate performance, fitness to practise issues, specialty choice, preparedness, satisfaction, teaching styles, entry criteria and institutional factors. METHOD: Aggregated data were collected for 50 measures across 29 UK medical schools. Data include institutional history (e.g. rate of production of hospital and GP specialists in the past), curricular influences (e.g. PBL schools, spend per student, staff-student ratio), selection measures (e.g. entry grades), teaching and assessment (e.g. traditional vs PBL, specialty teaching, self-regulated learning), student satisfaction, Foundation selection scores, Foundation satisfaction, postgraduate examination performance and fitness to practise (postgraduate progression, GMC sanctions). Six specialties (General Practice, Psychiatry, Anaesthetics, Obstetrics and Gynaecology, Internal Medicine, Surgery) were examined in more detail. RESULTS: Medical school differences are stable across time (median alpha = 0.835). The 50 measures were highly correlated, 395 (32.2%) of 1225 correlations being significant with p < 0.05, and 201 (16.4%) reached a Tukey-adjusted criterion of p < 0.0025. Problem-based learning (PBL) schools differ on many measures, including lower performance on postgraduate assessments. While these are in part explained by lower entry grades, a surprising finding is that schools such as PBL schools which reported greater student satisfaction with feedback also showed lower performance at postgraduate examinations. More medical school teaching of psychiatry, surgery and anaesthetics did not result in more specialist trainees. Schools that taught more general practice did have more graduates entering GP training, but those graduates performed less well in MRCGP examinations, the negative correlation resulting from numbers of GP trainees and exam outcomes being affected both by non-traditional teaching and by greater historical production of GPs. Postgraduate exam outcomes were also higher in schools with more self-regulated learning, but lower in larger medical schools. A path model for 29 measures found a complex causal nexus, most measures causing or being caused by other measures. Postgraduate exam performance was influenced by earlier attainment, at entry to Foundation and entry to medical school (the so-called academic backbone), and by self-regulated learning. Foundation measures of satisfaction, including preparedness, had no subsequent influence on outcomes. Fitness to practise issues were more frequent in schools producing more male graduates and more GPs. CONCLUSIONS: Medical schools differ in large numbers of ways that are causally interconnected. Differences between schools in postgraduate examination performance, training problems and GMC sanctions have important implications for the quality of patient care and patient safety
The Analysis of Teaching of Medical Schools (AToMS) survey: an analysis of 47,258 timetabled teaching events in 25 UK medical schools relating to timing, duration, teaching formats, teaching content, and problem-based learning
BACKGROUND: What subjects UK medical schools teach, what ways they teach subjects, and how much they teach those subjects is unclear. Whether teaching differences matter is a separate, important question. This study provides a detailed picture of timetabled undergraduate teaching activity at 25 UK medical schools, particularly in relation to problem-based learning (PBL). METHOD: The Analysis of Teaching of Medical Schools (AToMS) survey used detailed timetables provided by 25 schools with standard 5-year courses. Timetabled teaching events were coded in terms of course year, duration, teaching format, and teaching content. Ten schools used PBL. Teaching times from timetables were validated against two other studies that had assessed GP teaching and lecture, seminar, and tutorial times. RESULTS: A total of 47,258 timetabled teaching events in the academic year 2014/2015 were analysed, including SSCs (student-selected components) and elective studies. A typical UK medical student receives 3960 timetabled hours of teaching during their 5-year course. There was a clear difference between the initial 2Â years which mostly contained basic medical science content and the later 3Â years which mostly consisted of clinical teaching, although some clinical teaching occurs in the first 2Â years. Medical schools differed in duration, format, and content of teaching. Two main factors underlay most of the variation between schools, Traditional vs PBL teaching and Structured vs Unstructured teaching. A curriculum map comparing medical schools was constructed using those factors. PBL schools differed on a number of measures, having more PBL teaching time, fewer lectures, more GP teaching, less surgery, less formal teaching of basic science, and more sessions with unspecified content. DISCUSSION: UK medical schools differ in both format and content of teaching. PBL and non-PBL schools clearly differ, albeit with substantial variation within groups, and overlap in the middle. The important question of whether differences in teaching matter in terms of outcomes is analysed in a companion study (MedDifs) which examines how teaching differences relate to university infrastructure, entry requirements, student perceptions, and outcomes in Foundation Programme and postgraduate training
Structured lifestyle education to support weight loss for people with schizophrenia, schizoaffective disorder and first episode psychosis: the STEPWISE RCT.
BACKGROUND: Obesity is twice as common in people with schizophrenia as in the general population. The National Institute for Health and Care Excellence guidance recommends that people with psychosis or schizophrenia, especially those taking antipsychotics, be offered a healthy eating and physical activity programme by their mental health care provider. There is insufficient evidence to inform how these lifestyle services should be commissioned. OBJECTIVES: To develop a lifestyle intervention for people with first episode psychosis or schizophrenia and to evaluate its clinical effectiveness, cost-effectiveness, delivery and acceptability. DESIGN: A two-arm, analyst-blind, parallel-group, randomised controlled trial, with a 1 : 1 allocation ratio, using web-based randomisation; a mixed-methods process evaluation, including qualitative case study methods and logic modelling; and a cost-utility analysis. SETTING: Ten community mental health trusts in England. PARTICIPANTS: People with first episode psychosis, schizophrenia or schizoaffective disorder. INTERVENTIONS: Intervention group: (1) four 2.5-hour group-based structured lifestyle self-management education sessions, 1 week apart; (2) multimodal fortnightly support contacts; (3) three 2.5-hour group booster sessions at 3-monthly intervals, post core sessions. Control group: usual care assessed through a longitudinal survey. All participants received standard written lifestyle information. MAIN OUTCOME MEASURES: The primary outcome was change in weight (kg) at 12 months post randomisation. The key secondary outcomes measured at 3 and 12 months included self-reported nutrition (measured with the Dietary Instrument for Nutrition Education questionnaire), objectively measured physical activity measured by accelerometry [GENEActiv (Activinsights, Kimbolton, UK)], biomedical measures, adverse events, patient-reported outcome measures and a health economic assessment. RESULTS: The trial recruited 414 participants (intervention arm: 208 participants; usual care: 206 participants) between 10 March 2015 and 31 March 2016. A total of 341 participants (81.6%) completed the trial. A total of 412 participants were analysed. After 12 months, weight change did not differ between the groups (mean difference 0.0 kg, 95% confidence interval -1.59 to 1.67 kg; p = 0.964); physical activity, dietary intake and biochemical measures were unchanged. Glycated haemoglobin, fasting glucose and lipid profile were unchanged by the intervention. Quality of life, psychiatric symptoms and illness perception did not change during the trial. There were three deaths, but none was related to the intervention. Most adverse events were expected and related to the psychiatric illness. The process evaluation showed that the intervention was acceptable, with participants valuing the opportunity to interact with others facing similar challenges. Session feedback indicated that 87.2% of participants agreed that the sessions had met their needs. Some indicated the desire for more ongoing support. Professionals felt that the intervention was under-resourced and questioned the long-term sustainability within current NHS settings. Professionals would have preferred greater access to participants' behaviour data to tailor the intervention better. The incremental cost-effectiveness ratio from the health-care perspective is £246,921 per quality-adjusted life-year (QALY) gained and the incremental cost-effectiveness ratio from the societal perspective is £367,543 per QALY gained. CONCLUSIONS: Despite the challenges of undertaking clinical research in this population, the trial successfully recruited and retained participants, indicating a high level of interest in weight management interventions; however, the STEPWISE intervention was neither clinically effective nor cost-effective. Further research will be required to define how overweight and obesity in people with schizophrenia should be managed. The trial results suggest that lifestyle programmes for people with schizophrenia may need greater resourcing than for other populations, and interventions that have been shown to be effective in other populations, such as people with diabetes mellitus, are not necessarily effective in people with schizophrenia. TRIAL REGISTRATION: Current Controlled Trials ISRCTN19447796. FUNDING: This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 22, No. 65. See the NIHR Journals Library website for further project information
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