Developing an implementation fidelity checklist for a vocational rehabilitation intervention

Background: Despite growing numbers of studies reporting the efficacy of complex interventions and their implementation, many studies fail to report information on implementation fidelity or describe how fidelity measures used within the study were developed. This study aimed to develop a fidelity checklist for measuring the implementation fidelity of an early, stroke-specialist vocational rehabilitation intervention (ESSVR) in the RETAKE trial. Methods: To develop the fidelity measure, previous checklists were reviewed to inform the assessment structure, and core intervention components were extracted from intervention descriptions into a checklist, which was ratified by eight experts in fidelity measurement and complex interventions. Guidance notes were generated to assist with checklist completion. To test the measure, two researchers independently applied the checklist to fifteen stroke survivor intervention case notes using retrospective observational case review. The scoring was assessed for interrater reliability. Results: A fidelity checklist containing 21 core components and 6 desirable components across 4 stages of intervention delivery was developed with corresponding guidance notes. Interrater reliability of each checklist item ranged from moderate to perfect (Cohen’s kappa 0.69–1). Conclusions: The resulting checklist to assess implementation fidelity is fit for assessing the delivery of vocational rehabilitation for stroke survivors using retrospective observational case review. The checklist proved its utility as a measure of fidelity and may be used to inform the design of future implementation strategies.publishedVersio

Tumor growth instability and the onset of invasion

Motivated by experimental observations, we develop a mathematical model of chemotactically directed tumor growth. We present an analytical study of the model as well as a numerical one. The mathematical analysis shows that: (i) tumor cell proliferation by itself cannot generate the invasive branching behaviour observed experimentally, (ii) heterotype chemotaxis provides an instability mechanism that leads to the onset of tumor invasion and (iii) homotype chemotaxis does not provide such an instability mechanism but enhances the mean speed of the tumor surface. The numerical results not only support the assumptions needed to perform the mathematical analysis but they also provide evidence of (i), (ii) and (iii). Finally, both the analytical study and the numerical work agree with the experimental phenomena.Comment: 12 pages, 8 figures, revtex

MAPO: Mining and Recommending API Usage Patterns

To improve software productivity, when constructing new software systems, programmers often reuse existing libraries or frameworks by invoking methods provided in their APIs. Those API methods, however, are often complex and not well documented. To get familiar with how those API methods are used, programmers often exploit a source code search tool to search for code snippets that use the API methods of interest. However, the returned code snippets are often large in number, and the huge number of snippets places a barrier for programmers to locate useful ones. In order to help programmers overcome this barrier, we have developed an API usage mining framework and its supporting tool called MAPO (Mining API usage Pattern from Open source repositories) for mining API usage patterns automatically. A mined pattern describes that in a certain usage scenario, some API methods are frequently called together and their usages follow some sequential rules. MAPO further recommends the mined API usage patterns and their associated code snippets upon programmers' requests. Our experimental results show that with these patterns MAPO helps programmers locate useful code snippets more effectively than two state-of-the-art code search tools. To investigate whether MAPO can assist programmers in programming tasks, we further conducted an empirical study. The results show that using MAPO, programmers produce code with fewer bugs when facing relatively complex API usages, comparing with using the two state-of-the-art code search tools. ? 2009 Springer Berlin Heidelberg.EI

Dietary carbohydrates and breast cancer risk: A prospective study of the roles of overall glycemic index and glycemic load

We examined breast cancer risk in association with overall glycemic index (GI), glycemic load (GL), and dietary carbohydrate and sugar intake in a prospective cohort of 49,613 Canadian women enrolled in the National Breast Screening Study who completed a self‐administered food frequency questionnaire between 1980 and 1985. Linkages to national mortality and cancer databases yielded data on deaths and cancer incidence, with follow‐up ending between 1998 and 2000. During a mean follow‐up of 16.6 years, we observed 1,461 incident breast cancer cases. GI, GL, total carbohydrate and total sugar intake were not associated with breast cancer risk in the total cohort. However, there was evidence of effect modification of the association between GI and breast cancer risk by menopausal status (p = 0.01), the hazard ratio for the highest versus the lowest quintile level of GI being 0.78 (95% CI = 0.52–1.16; ptrend = 0.12) in premenopausal women and 1.87 (95% CI = 1.18–2.97; ptrend = 0.01) in postmenopausal women. The associations between GI and GL were not modified by body mass index (BMI) or by vigorous physical activity among pre‐ or postmenopausal women. Similarly, the associations between GI/GL and risk in postmenopausal women were not modified by BMI, vigorous physical activity, or ever use of hormone replacement therapy (HRT), although the associations were slightly stronger among those who reported no vigorous physical activity (ptrend = 0.02), among those who reported ever using HRT (ptrend = 0.02) and among normal‐weight women (BMI \u3c 25 kg/m2; ptrend = 0.03). Our data suggest that consumption of diets with high GI values may be associated with increased risk of breast cancer among postmenopausal women, possibly more so among subgroups defined by participation in vigorous physical activity, ever use of HRT and those who are not overweight

Pyrrolo[3,2-d]pyrimidine Derivatives as Type II Kinase Insert Domain Receptor (KDR) Inhibitors: CoMFA and CoMSIA Studies

Kinase insert domain receptor (KDR) inhibitors have been proved to be very effective anticancer agents. Molecular docking, 3D-QSAR methods, CoMFA and CoMSIA were performed on pyrrolo[3,2-d]pyrimidine derivatives as non-ATP competitive KDR inhibitors (type II). The bioactive conformation was explored by docking one potent compound 20 into the active site of KDR in its DFG-out inactive conformation. The constructed CoMFA and CoMSIA models produced statistically significant results with the cross-validated correlation coefficients q2 of 0.542 and 0.552, non-cross-validated correlation coefficients r2 of 0.912 and 0.955, and predicted correction coefficients r2pred of 0.913 and 0.897, respectively. These results ensure the CoMFA and CoMSIA models as a tool to guide the design of a series of new potent KDR inhibitors

Optical Intensity Interferometry with the Cherenkov Telescope Array

With its unprecedented light-collecting area for night-sky observations, the Cherenkov Telescope Array (CTA) holds great potential for also optical stellar astronomy, in particular as a multi-element intensity interferometer for realizing imaging with sub-milliarcsecond angular resolution. Such an order-of-magnitude increase of the spatial resolution achieved in optical astronomy will reveal the surfaces of rotationally flattened stars with structures in their circumstellar disks and winds, or the gas flows between close binaries. Image reconstruction is feasible from the second-order coherence of light, measured as the temporal correlations of arrival times between photons recorded in different telescopes. This technique (once pioneered by Hanbury Brown and Twiss) connects telescopes only with electronic signals and is practically insensitive to atmospheric turbulence and to imperfections in telescope optics. Detector and telescope requirements are very similar to those for imaging air Cherenkov observatories, the main difference being the signal processing (calculating cross correlations between single camera pixels in pairs of telescopes). Observations of brighter stars are not limited by sky brightness, permitting efficient CTA use during also bright-Moon periods. While other concepts have been proposed to realize kilometer-scale optical interferometers of conventional amplitude (phase-) type, both in space and on the ground, their complexity places them much further into the future than CTA, which thus could become the first kilometer-scale optical imager in astronomy.Comment: Astroparticle Physics, in press; 47 pages, 10 figures, 124 reference

A study of mapping usual care and unmet need for vocational rehabilitation and psychological support following major trauma in five health districts in the UK

Traumatic injuries in working age adults are a global public health problem. Traumatic injury or ‘major trauma’ describes serious and often multiple injuries where there is a strong possibility of death or disability1 (e.g. traumatic brain injuries, complex fractures). Survivors of such injuries may experience physical, social, and psychological problems, such as pain, fatigue, depression and anxiety, or hidden disabilities, such as cognitive problems. A significant number of people experiencing trauma have residual problems affecting their ability to return to, and remain in, work2, 3. Therefore, it is important that rehabilitation to support these individuals is available long-term and addresses all issues

Early, specialist vocational rehabilitation to facilitate return to work after traumatic brain injury: the FRESH feasibility RCT

Background Up to 160,000 people incur traumatic brain injury (TBI) each year in the UK. TBI can have profound effects on many areas of human functioning, including participation in work. There is limited evidence of the clinical effectiveness and cost-effectiveness of vocational rehabilitation (VR) after injury to promote early return to work (RTW) following TBI. Objective To assess the feasibility of a definitive, multicentre, randomised controlled trial (RCT) of the clinical effectiveness and cost-effectiveness of early, specialist VR plus usual care (UC) compared with UC alone on work retention 12 months post TBI. Design A multicentre, feasibility, parallel-group RCT with a feasibility economic evaluation and an embedded mixed-methods process evaluation. Randomisation was by remote computer-generated allocation. Setting Three NHS major trauma centres (MTCs) in England. Participants Adults with TBI admitted for > 48 hours and working or studying prior to injury. Interventions Early specialist TBI VR delivered by occupational therapists (OTs) in the community using a case co-ordination model. Main outcome measures Self-reported RTW 12 months post randomisation, mood, functional ability, participation, work self-efficacy, quality of life and work ability. Feasibility outcomes included recruitment and retention rates. Follow-up was by postal questionnaires in two centres and face to face in one centre. Those collecting data were blind to treatment allocation. Results Out of 102 target participants, 78 were recruited (39 randomised to each arm), representing 39% of those eligible and 5% of those screened. Approximately 2.2 patients were recruited per site per month. Of those, 56% had mild injuries, 18% had moderate injuries and 26% had severe injuries. A total of 32 out of 45 nominated carers were recruited. A total of 52 out of 78 (67%) TBI participants responded at 12 months (UC, n = 23; intervention, n = 29), completing 90% of the work questions; 21 out of 23 (91%) UC respondents and 20 out of 29 (69%) intervention participants returned to work at 12 months. Two participants disengaged from the intervention. Face-to-face follow-up was no more effective than postal follow-up. RTW was most strongly related to social participation and work self-efficacy. It is feasible to assess the cost-effectiveness of VR. Intervention was delivered as intended and valued by participants. Factors likely to affect a definitive trial include deploying experienced OTs, no clear TBI definition or TBI registers, and repatriation of more severe TBI from MTCs, affecting recruitment of those most likely to benefit/least likely to drop out. Limitations Target recruitment was not reached, but mechanisms to achieve this in future studies were identified. Retention was lower than expected, particularly in UC, potentially biasing estimates of the 12-month RTW rate. Conclusions This study met most feasibility objectives. The intervention was delivered with high fidelity. When objectives were not met, strategies to ensure feasibility of a full trial were identified. Future work should test two-stage recruitment and include resources to recruit from ‘spokes’. A broader measure covering work ability, self-efficacy and participation may be a more sensitive outcome. Trial registration Current Controlled Trials ISRCTN38581822. 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. 33. See the NIHR Journals Library website for further project information

Heat load of a P-doped GaAs photocathode in SRF electron gun

Many efforts were made over the last decades to develop a better polarized electron source for the high energy physics. Several laboratories operate DC guns with the Gallium-Arsenide photo-cathode, which yield a highly polarized electron beam. However, the beam's emittance might well be improved using a Superconducting RF electron gun, which delivers beams of higher brightness than DC guns does, because the field gradient at the cathode is higher. SRF guns with metal cathodes and CsTe cathodes have been tested successfully. To produce polarized electrons, a Gallium-Arsenide photo-cathode must be used: an experiment to do so in a superconducting RF gun is under way at BNL. Since the cathode will be normal conducting, the problem about the heat load stemming from the cathode arises. We present our measurements of the electrical resistance of GaAs at cryogenic temperatures, a prediction of the heat load and the verification by measuring the quality factor of the gun with and without cathode