Constraints on the Variations of the Fundamental Couplings

We reconsider several current bounds on the variation of the fine-structure constant in models where all gauge and Yukawa couplings vary in an interdependent manner, as would be expected in unified theories. In particular, we re-examine the bounds established by the Oklo reactor from the resonant neutron capture cross-section of 149Sm. By imposing variations in \Lambda_{QCD} and the quark masses, as dictated by unified theories, the corresponding bound on the variation of the fine-structure constant can be improved by about 2 orders of magnitude in such theories. In addition, we consider possible bounds on variations due to their effect on long lived \alpha- and \beta-decay isotopes, particularly 147Sm and 187Re. We obtain a strong constraint on \Delta \alpha / \alpha, comparable to that of Oklo but extending to a higher redshift corresponding to the age of the solar system, from the radioactive life-time of 187Re derived from meteoritic studies. We also analyze the astrophysical consequences of perturbing the decay Q values on bound state \beta-decays operating in the s-process.Comment: 25 pages, latex, 5 eps figure

Sleep-Related Falling Out of Bed in Parkinson's Disease

Background and purposeSleep-related falling out of bed (SFOB), with its potential for significant injury, has not been a strong focus of investigation in Parkinson's disease (PD) to date. We describe the demographic and clinical characteristics of PD patients with and without SFOB.MethodsWe performed a retrospective analysis of 50 consecutive PD patients, who completed an REM sleep behavior disorder screening questionnaire (RBDSQ), questionnaires to assess for RBD clinical mimickers and questions about SFOB and resulting injuries. Determination of high risk for RBD was based on an RBDSQ score of 5 or greater.ResultsThirteen patients reported history of SFOB (26%). Visual hallucinations, sleep-related injury, quetiapine and amantadine use were more common in those patients reporting SFOB. Twenty-two patients (44%) fulfilled criteria for high risk for RBD, 12 of which (55%) reported SFOB. Five patients reported injuries related to SFOB. SFOB patients had higher RBDSQ scores than non-SFOB patients (8.2±3.0 vs. 3.3±2.0, p<0.01). For every one unit increase in RBDSQ score, the likelihood of SFOB increased two-fold (OR 2.4, 95% CI 1.3-4.2, p<0.003).ConclusionsSFOB may be a clinical marker of RBD in PD and should prompt confirmatory polysomnography and pharmacologic treatment to avoid imminent injury. Larger prospective studies are needed to identify risk factors for initial and recurrent SFOB in PD

Caracteres ultrastructuraux des macrophages alveolaires de sujets asthmatiques

International audienc

Calcification of the abdominal aorta as an independent predictor of cardiovascular events: A meta-analysis

Context: Abdominal aortic calcification (AAC) is a common finding in patients with atherosclerosis. Objective: The aim of this study was to demonstrate the incremental value of AAC in predicting long term cardiovascular (CV) outcome by conducting a meta-analysis of observational studies. Data sources: MEDLINE and Cochrane databases. Study selection Longitudinal studies with at least 2 years of follow-up, reporting the influence of AAC on CV outcome of general population patients. Data extraction: Four separate end points - coronary events, cerebrovascular events, all CV events and CV related death - were tested for their relationship with AAC at baseline, using weighted random effects meta-analysis. Heterogeneity was calculated using Q and I 2statistic tests. Publication bias was assessed by funnel plot symmetry and trim and fill methods. The importance of calcium quantification was also explored (sensitivity analysis). Results: 10 studies were included. An increased relative risk (RR) was found for all end points: for coronary events (five studies, n=11250) 1.81 (95% CI 1.54 to 2.14); for cerebrovascular events (four studies, n=9736) 1.37 (1.22 to 3.54); for all CV events (four studies, n=4960) 1.64 (1.24 to 2.17); and for CV death (three studies, n=4986) 1.72 (1.03 to 2.86). Analysis of studies presenting results in categories (no/minimal, moderate and severe calcification) revealed a stepwise increase in the RR for all end points. Significant heterogeneity was found in the included studies. Sources of heterogeneity were identified in the publication date, duration of follow-up, and mean age and gender differences in the included patient cohorts. Conclusion: Existing data suggest that AAC is a strong predictor of CV related events or death in the general population. The predictive impact is greater in more calcified aortas. The generalisability of the meta-anal