Numerical simulation of a wave-guide mixing layer on a Cray C-90

The development of a three-dimensional spatially evolving compressible mixing layer is investigated numerically using a parallel implementation of Adaptive Mesh Refinement (AMR) on a Cray C-90. The parallel implementation allowed the flow to be highly resolved while significantly reducing the wall-clock runtime. A sustained computation rate of 5.3 Gigaflops including I/O was obtained for a typical production run on a 16 processor machine. A novel mixing layer configuration is investigated where a pressure mismatch is maintained between the two inlet streams. In addition, the sonic character of the two streams is sufficiently different so that the pressure relief wave is trapped in the high speed stream. The trapped wave forces the mixing layer to form a characteristic cellular pattern. The cellular structure introduces curvature into the mixing layer that excites centrifugal instabilities characterized by large-scale counter-rotating vortical pairs embedded within the mixing layer. These are the dominant feature of the flow. Visualizations of these structures in cross-section show the pumping action which lifts dense fluid up into light gas. This effect has a strong impact on mixing enhancement as monitored by a conserved scalar formulation. Once the large-scale structures axe well established in the flow and undergo intensification from favorable velocity gradients, the time-averaged integrated product shows almost a four-fold increase. A spectral analysis of the flow-field over the cellular structures, as part of a full space-time analysis, shows these structures to be zero-frequency modes that develop from low level essentially broad-banded noise. This characterization of the vortical structures and their appearance is consistent with a recent linear stability analysis, of a mixing layer over a curved wall that predicts the most unstable modes to be zero frequency streamwise vortices

Enhanced differential magnetostrictive response in annealed Terfenol‐D

The field and pressure dependencies of the magnetostriction of Tb0.316Dy0.684Fe1.982 have been measured in a grain‐oriented rod after thermally annealing for 1 day at 850 °C and for 4 days at 950 °C in an argon atmosphere. The results of the heat treatment are a fivefold increase in the strain coefficient d 33(=dλ/dH) and a 100% increase in the maximum strain (λ). There was also an increase in the λ‐vs‐Hhysteresis. Under compressive uniaxial stress there was virtually no bulk change in magnetostrictive strain until the field exceeded a critical value which depended on the applied stress, for instance ∼12 kA/m under a stress of 6 MPa

Public and patient involvement in child health research and service improvements: a survey of hospital doctors

Objectives: To determine whether paediatricians are supported by their organisations to encourage patient and public involvement (PPI) in research activities and clinical improvement work, the challenges they face and how they think these could be addressed by the Royal College of Paediatrics and Child Health (RCPCH). Design: A survey. Setting: UK consultant paediatricians and staff associate specialist and specialty (SAS) doctors who are members of RCPCH. Main outcome measures: The proportion of respondents who said that PPI was central to research and service improvements in their organisation, the type of local support for PPI activity, challenges in undertaking PPI and the support members wanted from RCPCH. Results: There was a response rate of 44.4% (n=1924). In their organisation, 29.1% of respondents stated PPI was central to research and 36.1% to service improvement; 46% were unaware of support for PPI and 15% said there was no support. The main challenges for PPI activity were a lack of clinician time, local support and funding. Respondents wanted RCPCH to advocate for protected time for PPI, provide access to PPI groups and deliver guidance and training. Conclusions: The majority of paediatricians feel unsupported to undertake PPI activity by their local organisation. The RCPCH has a key role to enable all paediatricians to work with children, young people and their carers to improve the quality of research and clinical services as demonstrated by RCPCH's ongoing activity in these crucial and important areas

The changing UK paediatric consultant workforce: report from the Royal College of Paediatrics and Child Health

Objectives To determine if there had been changes in the size of the UK paediatric workforce and working patterns between 1999 and 2013. Design Analysis of prospectively collected datasets. Setting UK consultant paediatricians. Interventions Data from the Royal College of Paediatrics and Child Health's workforce census from 1999 to 2013 and the annual surveys of new paediatric Certificate of Completion of Training (CCT) and Certificate of Equivalence of Specialist Registration (CESR) holders between 2010 and 2013. Main outcome measures Paediatric consultant numbers, programmed activities (PAs) and resident shift working. Results The UK paediatric consultant workforce grew from 1933 in 1999 to 3718 in 2013. Over the same time period, there was a decline in the number of consultants with a primary academic contract from 210 to 143. There was an increase in the proportion of consultants who were female (40% in 1999 to 50% in 2013, p<0.01). The median number of PAs declined from 11 in 2009 to 10 in 2013 (p<0.001) as did the median number of PAs for supporting professional activities (2.5–2.3, p<0.001). In 2013, 38% of new consultants in general paediatrics or neonatology were working resident shifts. Between 2009 and 2013, the proportion of less than full-time working consultants rose from 18% to 22%, which was more common among female consultants (35% vs 9%). Conclusion The paediatric consultant workforce has doubled since 1999, but more are working less than full time. The decline in those with a primary academic contract is of concern

Enhanced motivational interviewing for reducing weight and increasing physical activity in adults with high cardiovascular risk: the MOVE IT three-arm RCT.

BACKGROUND: Motivational interviewing (MI) enhanced with behaviour change techniques (BCTs) and deployed by health trainers targeting multiple risk factors for cardiovascular disease (CVD) may be more effective than interventions targeting a single risk factor. OBJECTIVES: The clinical effectiveness and cost-effectiveness of an enhanced lifestyle motivational interviewing intervention for patients at high risk of CVD in group settings versus individual settings and usual care (UC) in reducing weight and increasing physical activity (PA) were tested. DESIGN: This was a three-arm, single-blind, parallel randomised controlled trial. SETTING: A total of 135 general practices across all 12 South London Clinical Commissioning Groups were recruited. PARTICIPANTS: A total of 1742 participants aged 40-74 years with a ≥ 20.0% risk of a CVD event in the following 10 years were randomised. INTERVENTIONS: The intervention was designed to integrate MI and cognitive-behavioural therapy (CBT), delivered by trained healthy lifestyle facilitators in 10 sessions over 1 year, in group or individual format. The control group received UC. RANDOMISATION: Simple randomisation was used with computer-generated randomisation blocks. In each block, 10 participants were randomised to the group, individual or UC arm in a 4 : 3 : 3 ratio. Researchers were blind to the allocation. MAIN OUTCOME MEASURES: The primary outcomes are change in weight (kg) from baseline and change in PA (average number of steps per day over 1 week) from baseline at the 24-month follow-up, with an interim follow-up at 12 months. An economic evaluation estimates the relative cost-effectiveness of each intervention. Secondary outcomes include changes in low-density lipoprotein cholesterol and CVD risk score. RESULTS: The mean age of participants was 69.75 years (standard deviation 4.11 years), 85.5% were male and 89.4% were white. At the 24-month follow-up, the group and individual intervention arms were not more effective than UC in increasing PA [mean 70.05 steps, 95% confidence interval (CI) -288 to 147.9 steps, and mean 7.24 steps, 95% CI -224.01 to 238.5 steps, respectively] or in reducing weight (mean -0.03 kg, 95% CI -0.49 to 0.44 kg, and mean -0.42 kg, 95% CI -0.93 to 0.09 kg, respectively). At the 12-month follow-up, the group and individual intervention arms were not more effective than UC in increasing PA (mean 131.1 steps, 95% CI -85.28 to 347.48 steps, and mean 210.22 steps, 95% CI -19.46 to 439.91 steps, respectively), but there were reductions in weight for the group and individual intervention arms compared with UC (mean -0.52 kg, 95% CI -0.90 to -0.13 kg, and mean -0.55 kg, 95% CI -0.95 to -0.14 kg, respectively). The group intervention arm was not more effective than the individual intervention arm in improving outcomes at either follow-up point. The group and individual interventions were not cost-effective. CONCLUSIONS: Enhanced MI, in group or individual formats, targeted at members of the general population with high CVD risk is not effective in reducing weight or increasing PA compared with UC. Future work should focus on ensuring objective evidence of high competency in BCTs, identifying those with modifiable factors for CVD risk and improving engagement of patients and primary care. TRIAL REGISTRATION: Current Controlled Trials ISRCTN84864870. 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. 23, No. 69. See the NIHR Journals Library website for further project information. This research was part-funded by the NIHR Biomedical Research Centre at South London and Maudsley NHS Foundation Trust and King's College London

Struggling to a monumental triumph : Re-assessing the final stages of the smallpox eradication program in India, 1960-1980

The global smallpox program is generally presented as the brainchild of a handful of actors from the WHO headquarters in Geneva and at the agency's regional offices. This article attempts to present a more complex description of the drive to eradicate smallpox. Based on the example of India, a major focus of the campaign, it is argued that historians and public health officials should recognize the varying roles played by a much wider range of participants. Highlighting the significance of both Indian and international field officials, the author shows how bureaucrats and politicians at different levels of administration and society managed to strengthen—yet sometimes weaken—important program components. Centrally dictated strategies developed at WHO offices in Geneva and New Delhi, often in association with Indian federal authorities, were reinterpreted by many actors and sometimes changed beyond recognition

Multifaceted contributions : health workers and smallpox eradication in India

Smallpox eradication in South Asia was a result of the efforts of many grades of health-workers. Working from within the confines of international organisations and government structures, the role of the field officials, who were of various nationalities and also drawn from the cities and rural enclaves of the countries in these regions, was crucial to the development and deployment of policies. However, the role of these personnel is often downplayed in official histories and academic histories, which highlight instead the roles played by a handful of senior officials within the World Health Organization and the federal governments in the sub-continent. This article attempts to provide a more rounded assessment of the complex situation in the field. In this regard, an effort is made to underline the great usefulness of the operational flexibility displayed by field officers, wherein lessons learnt in the field were made an integral part of deploying local campaigns; careful engagement with the communities being targeted, as well as the employment of short term workers from amongst them, was an important feature of this work

Probing the ultrafast energy dissipation mechanism of the sunscreen oxybenzone after UVA irradiation

Oxybenzone is a common constituent of many commercially available sunscreens providing photoprotection from ultraviolet light incident on the skin. Femtosecond transient electronic and vibrational absorption spectroscopies have been used to investigate the non-radiative relaxation pathways of oxybenzone in cyclohexane and methanol after excitation in the UVA region. The present data suggest that the photoprotective properties of oxybenzone can be understood in terms of an initial ultrafast excited state enol -> keto tautomerization, followed by efficient internal conversion and subsequent vibrational relaxation to the ground state (enol) tautomer