Absorption of Energy at a Metallic Surface due to a Normal Electric Field

The effect of an oscillating electric field normal to a metallic surface may be described by an effective potential. This induced potential is calculated using semiclassical variants of the random phase approximation (RPA). Results are obtained for both ballistic and diffusive electron motion, and for two and three dimensional systems. The potential induced within the surface causes absorption of energy. The results are applied to the absorption of radiation by small metal spheres and discs. They improve upon an earlier treatment which used the Thomas-Fermi approximation for the effective potential.Comment: 19 pages (Plain TeX), 2 figures, 1 table (Postscript

Drivers for change in primary care of diabetes following a protected learning time educational event: interview study of practitioners

Background: A number of protected learning time schemes have been set up in primary care across the United Kingdom but there has been little published evidence of their impact on processes of care. We undertook a qualitative study to investigate the perceptions of practitioners involved in a specific educational intervention in diabetes as part of a protected learning time scheme for primary health care teams, relating to changing processes of diabetes care in general practice. Methods: We undertook semistructured interviews of key informants from a sample of practices stratified according to the extent they had changed behaviour in prescribing of ramipril and diabetes care more generally, following a specific educational intervention in Lincolnshire, United Kingdom. Interviews sought information on facilitators and barriers to change in organisational behaviour for the care of diabetes. Results: An interprofessional protected learning time scheme event was perceived by some but not all participants as bringing about changes in processes for diabetes care. Participants cited examples of change introduced partly as a result of the educational session. This included using ACE inhibitors as first line for patients with diabetes who developed hypertension, increased use of aspirin, switching patients to glitazones, and conversion to insulin either directly or by referral to secondary care. Other reported factors for change, unrelated to the educational intervention, included financially driven performance targets, research evidence and national guidance. Facilitators for change linked to the educational session were peer support and teamworking supported by audit and comparative feedback. Conclusion: This study has shown how a protected learning time scheme, using interprofessional learning, local opinion leaders and early implementers as change agents may have influenced changes in systems of diabetes care in selected practices but also how other confounding factors played an important part in changes that occurred in practice

Partitioning of starter bacteria and added exogenous enzyme activities between curd and whey during Cheddar cheese manufacture

peer-reviewedPartitioning of starter bacteria and enzyme activities was investigated at different stages of Cheddar cheese manufacture using three exogenous commercial enzyme preparations added to milk or at salting. The enzyme preparations used were: Accelase AM317, Accelase AHC50, Accelerzyme CPG. Flow cytometric analysis indicated that AHC50 or AM317 consisted of permeabilised or dead cells and contained a range of enzyme activities. The CPG preparation contained only carboxypeptidase activity. Approximately 90% of starter bacteria cells partitioned with the curd at whey drainage. However, key enzyme activities partitioned with the bulk whey in the range of 22%–90%. An increased level of enzyme partitioning with the curd was observed for AHC50 which was added at salting, indicating that the mode of addition influenced partitioning. These findings suggest that further scope exists to optimise both bacterial and exogenous enzyme incorporation into cheese curd to accelerate ripening.Department of Agriculture, Food and the Marin

The effect of stellar-mass black holes on the structural evolution of massive star clusters

We present the results of realistic N-body modelling of massive star clusters in the Magellanic Clouds, aimed at investigating a dynamical origin for the radius-age trend observed in these systems. We find that stellar-mass black holes, formed in the supernova explosions of the most massive cluster stars, can constitute a dynamically important population. If a significant number of black holes are retained (here we assume complete retention), these objects rapidly form a dense core where interactions are common, resulting in the scattering of black holes into the cluster halo, and the ejection of black holes from the cluster. These two processes heat the stellar component, resulting in prolonged core expansion of a magnitude matching the observations. Significant core evolution is also observed in Magellanic Cloud clusters at early times. We find that this does not result from the action of black holes, but can be reproduced by the effects of mass-loss due to rapid stellar evolution in a primordially mass segregated cluster.Comment: Accepted for publication in MNRAS Letters; 2 figures, 1 tabl

Crystallization and preliminary crystallographic analysis of the DNA gyrase B protein from B-stearothermophilus

DNA gyrase B (GyrB) from B. stearothermophilus has been crystallized in the presence of the non-hydrolyzable ATP analogue, 5'-adenylpl-beta-gamma-imidodiphosphate (ADPNP), by the dialysis method. A complete native data set to 3.7 Angstrom has been collected from crystals which belonged to the cubic space group I23 with unit-cell dimension a = 250.6 Angstrom. Self-rotation function analysis indicates the position of a molecular twofold axis. Low-resolution data sets of a thimerosal and a selenomethionine derivative have also been analysed. The heavy-atom positions are consistent with one dimer in the asymmetric unit

NHS reforms and the working lives of midwives and physiotherapists

From 2000 the NHS was subjected to a series of far reaching reforms, the purposes of which were to increase the role of the primary care sector in commissioning and providing services, promote healthier life styles, reduce health inequality, and improve service standards. These were seen as requiring a greater leadership role from health professionals, closer and more cooperative working between health professionals, and between health professionals, social services, and community and other service providers. The project surveyed a random sample of midwives and physiotherapists to investigate their perceptions of the effectiveness of the reforms, and their effects on working lives. The predominant perception was that NHS reforms had negatively affected the funding of their services; and had done little to improve service quality, delivery or organisation. Although the potential existed for the reforms to improve services, the necessary resources and required staffing were not made available and the objectives of the reforms were only partially secured by intensifying of work. The downside of this was a deterioration of the sociopsychological wellbeing of midwives and physiotherapists, especially the former, exacerbating the shortage of skilled and experienced. Shortage of staff and the associated increased work burdens were demoralising and demotivating; morale and job satisfaction declined, and job insecurity and labour turnover increased