Single atoms in a standing-wave dipole trap

We trap a single cesium atom in a standing-wave optical dipole trap. Special experimental procedures, designed to work with single atoms, are used to measure the oscillation frequency and the atomic energy distribution in the dipole trap. These methods rely on unambiguously detecting presence or loss of the atom using its resonance fluorescence in the magneto-optical trap.Comment: 8 pages, 7 figures, submitted to Phys. Rev.

An optical conveyor belt for single neutral atoms

Using optical dipole forces we have realized controlled transport of a single or any desired small number of neutral atoms over a distance of a centimeter with sub-micrometer precision. A standing wave dipole trap is loaded with a prescribed number of cesium atoms from a magneto-optical trap. Mutual detuning of the counter-propagating laser beams moves the interference pattern, allowing us to accelerate and stop the atoms at preselected points along the standing wave. The transportation efficiency is close to 100%. This optical "single-atom conveyor belt" represents a versatile tool for future experiments requiring deterministic delivery of a prescribed number of atoms on demand.Comment: 8 pages, 8 figures, submitted to Applied Physics

Grammaire pratique et conversations familières à l'usage des élèves sourds-muets de troisième année, par V.-G. Chambellan,...

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CF45-1, a Secreted Protein Which Participates in Dictyostelium Group Size Regulation

Developing Dictyostelium cells aggregate to form fruiting bodies containing typically 2 × 10(4) cells. To prevent the formation of an excessively large fruiting body, streams of aggregating cells break up into groups if there are too many cells. The breakup is regulated by a secreted complex of polypeptides called counting factor (CF). Countin and CF50 are two of the components of CF. Disrupting the expression of either of these proteins results in cells secreting very little detectable CF activity, and as a result, aggregation streams remain intact and form large fruiting bodies, which invariably collapse. We find that disrupting the gene encoding a third protein present in crude CF, CF45-1, also results in the formation of large groups when cells are grown with bacteria on agar plates and then starve. However, unlike countin(−) and cf50(−) cells, cf45-1(−) cells sometimes form smaller groups than wild-type cells when the cells are starved on filter pads. The predicted amino acid sequence of CF45-1 has some similarity to that of lysozyme, but recombinant CF45-1 has no detectable lysozyme activity. In the exudates from starved cells, CF45-1 is present in a ∼450-kDa fraction that also contains countin and CF50, suggesting that it is part of a complex. Recombinant CF45-1 decreases group size in colonies of cf45-1(−) cells with a 50% effective concentration (EC(50)) of ∼8 ng/ml and in colonies of wild-type and cf50(−) cells with an EC(50) of ∼40 ng/ml. Like countin(−) and cf50(−) cells, cf45-1(−) cells have high levels of cytosolic glucose, high cell-cell adhesion, and low cell motility. Together, the data suggest that CF45-1 participates in group size regulation in Dictyostelium

Editoriale. Ciò che la Psicologia ci dice delle scienze del nostro tempo

This is the final version of the article. Available from the publisher via the DOI in this record.Background: Chronic musculoskeletal pain is a common problem that is difficult to treat. Self-management support interventions may help people to manage this condition better; however, there is limited evidence showing that they improve clinical outcomes. Our overarching research question was ‘Does a self-management support programme improve outcomes for people living with chronic musculoskeletal pain?’. Aim: To develop, evaluate and test the clinical effectiveness and cost-effectiveness of a theoretically grounded self-management support intervention for people living with chronic musculoskeletal pain. Methods: In phase 1 we carried out two systematic reviews to synthesise the evidence base for self-management course content and delivery styles likely to help those with chronic pain. We also considered the psychological theories that might underpin behaviour change and pain management principles. Informed by these data we developed the Coping with persistent Pain, Evaluation Research in Self-management (COPERS) intervention, a group intervention delivered over 3 days with a top-up session after 2 weeks. It was led by two trained facilitators: a health-care professional and a layperson with experience of chronic pain. To ensure that we measured the most appropriate outcomes we reviewed the literature on potential outcome domains and measures and consulted widely with patients, tutors and experts. In a feasibility study we demonstrated that we could deliver the COPERS intervention in English and, to increase the generalisability of our findings, also in Sylheti for the Bangladeshi community. In phase 2 we ran a randomised controlled trial to test the clinical effectiveness and cost-effectiveness of adding the COPERS intervention to a best usual care package (usual care plus a relaxation CD and a pain toolkit leaflet). We recruited adults with chronic musculoskeletal pain largely from primary care and musculoskeletal physiotherapy services in two localities: east London and Coventry/Warwickshire. We collected follow-up data at 12 weeks (self-efficacy only) and 6 and 12 months. Our primary outcome was pain-related disability (Chronic Pain Grade disability subscale) at 12 months. We also measured costs, health utility (European Quality of Life-5 Dimensions), anxiety, depression [Hospital Anxiety and Depression Scale (HADS)], coping, pain acceptance and social integration. Data on the use of NHS services by participants were extracted from NHS electronic records. Results: We recruited 703 participants with a mean age of 60 years (range 19–94 years); 81% were white and 67% were female. Depression and anxiety symptoms were common, with mean HADS depression and anxiety scores of 7.4 [standard deviation (SD) 4.1] and 9.2 (SD 4.6), respectively. Intervention participants received 85% of the course content. At 12 months there was no difference between treatment groups in our primary outcome of pain-related disability [difference –1.0 intervention vs. control, 95% confidence interval (CI) –4.9 to 3.0]. However, self-efficacy, anxiety, depression, pain acceptance and social integration all improved more in the intervention group at 6 months. At 1 year these differences remained for depression (–0.7, 95% CI –1.2 to –0.2) and social integration (0.8, 95% CI, 0.4 to 1.2). The COPERS intervention had a high probability (87%) of being cost-effective compared with usual care at a threshold of £30,000 per quality-adjusted life-year. Conclusions: Although the COPERS intervention did not affect our primary outcome of pain-related disability, it improved psychological well-being and is likely to be cost-effective according to current National Institute for Health and Care Excellence criteria. The COPERS intervention could be used as a substitute for less well-evidenced (and more expensive) pain self-management programmes. Effective interventions to improve hard outcomes in chronic pain patients, such as disability, are still needed.The project was funded by the National Institute for Health Research Programme Grants for Applied Research programme and will be published in full in Programme Grants for Applied Research; Vol. 4, No. 14. See the NIHR Journals Library website for further project information

A randomised, blinded, trial of clopidogrel versus aspirin in patients at risk of ischaemic events (CAPRIE). CAPRIE Steering Committee

Many clinical trials have evaluated the benefit of long-term use of antiplatelet drugs in reducing the risk of clinical thrombotic events. Aspirin and ticlopidine have been shown to be effective, but both have potentially serious adverse effects. Clopidogrel, a new thienopyridine derivative similar to ticlopidine, is an inhibitor of platelet aggregation induced by adenosine diphosphate. METHODS: CAPRIE was a randomised, blinded, international trial designed to assess the relative efficacy of clopidogrel (75 mg once daily) and aspirin (325 mg once daily) in reducing the risk of a composite outcome cluster of ischaemic stroke, myocardial infarction, or vascular death; their relative safety was also assessed. The population studied comprised subgroups of patients with atherosclerotic vascular disease manifested as either recent ischaemic stroke, recent myocardial infarction, or symptomatic peripheral arterial disease. Patients were followed for 1 to 3 years. FINDINGS: 19,185 patients, with more than 6300 in each of the clinical subgroups, were recruited over 3 years, with a mean follow-up of 1.91 years. There were 1960 first events included in the outcome cluster on which an intention-to-treat analysis showed that patients treated with clopidogrel had an annual 5.32% risk of ischaemic stroke, myocardial infarction, or vascular death compared with 5.83% with aspirin. These rates reflect a statistically significant (p = 0.043) relative-risk reduction of 8.7% in favour of clopidogrel (95% Cl 0.3-16.5). Corresponding on-treatment analysis yielded a relative-risk reduction of 9.4%. There were no major differences in terms of safety. Reported adverse experiences in the clopidogrel and aspirin groups judged to be severe included rash (0.26% vs 0.10%), diarrhoea (0.23% vs 0.11%), upper gastrointestinal discomfort (0.97% vs 1.22%), intracranial haemorrhage (0.33% vs 0.47%), and gastrointestinal haemorrhage (0.52% vs 0.72%), respectively. There were ten (0.10%) patients in the clopidogrel group with significant reductions in neutrophils (< 1.2 x 10(9)/L) and 16 (0.17%) in the aspirin group. INTERPRETATION: Long-term administration of clopidogrel to patients with atherosclerotic vascular disease is more effective than aspirin in reducing the combined risk of ischaemic stroke, myocardial infarction, or vascular death. The overall safety profile of clopidogrel is at least as good as that of medium-dose aspirin