A new method to detect solar-like oscillations at very low S/N using statistical significance testing

We introduce a new method to detect solar-like oscillations in frequency power spectra of stellar observations, under conditions of very low signal to noise. The Moving-Windowed-Power-Search, or MWPS, searches the power spectrum for signatures of excess power, over and above slowly varying (in frequency) background contributions from stellar granulation and shot or instrumental noise. We adopt a false-alarm approach (Chaplin et al. 2011) to ascertain whether flagged excess power, which is consistent with the excess expected from solar-like oscillations, is hard to explain by chance alone (and hence a candidate detection). We apply the method to solar photometry data, whose quality was systematically degraded to test the performance of the MWPS at low signal-to-noise ratios. We also compare the performance of the MWPS against the frequently applied power-spectrum-of-power-spectrum (PSxPS) detection method. The MWPS is found to outperform the PSxPS method.Comment: 10 pages, 7 figures, accepted for publication in MNRAS, Added reference

Did the ban on smoking reduce the revenue in pubs and restaurants in Norway?

After 16 years of exemptions from the ban on indoor smoking in other places of work, Norway became the second country after Ireland to implement a smoke-free regime in pubs and restaurants. This paper evaluates the economic impact on the hospitality sector in a northern region with a cold climate. The data consists of bi-monthly observations of revenues in restaurants and pubs starting in January 1999 and ending in August 2007. Auto-regressive integrated moving average (ARIMA) intervention analysis was used to test for possible economic impacts, controlling for variations in temperature. The ban on smoking did not have a statistically significant effect on revenue in restaurants or on restaurant revenue as a share of personal consumption. There is also no evidence that the ban reduce revenues in bars, but there is some indication that it may have reduced bar revenue as a share of personal consumption. Conclusion: A large body of research has found no negative economic effect of smoke-free legislation on restaurant and bar sales in the United States, Australia and elsewhere Our study confirms these results in a northern region with a cold climate with respect to restaurants, but the results was more mixed for bars.Tobacco; economics; business; passive smoking; legislation

Evidence-based Research: a step between past and future research

VIII Congreso Iberoamericano de Nutrición. ¿Nutrición basada en la videncia o en la evidencia

Fast time variations of supernova neutrino fluxes and their detectability

In the delayed explosion scenario of core-collapse supernovae (SNe), the accretion phase shows pronounced convective overturns and a low-multipole hydrodynamic instability, the standing accretion shock instability (SASI). These effects imprint detectable fast time variations on the emerging neutrino flux. Among existing detectors, IceCube is best suited to this task, providing an event rate of ~1000 events per ms during the accretion phase for a fiducial SN distance of 10 kpc, comparable to what could be achieved with a megaton water Cherenkov detector. If the SASI activity lasts for several hundred ms, a Fourier component with an amplitude of 1% of the average signal clearly sticks out from the shot noise. We analyze in detail the output of axially symmetric hydrodynamical simulations that predict much larger amplitudes up to frequencies of a few hundred Hz. If these models are roughly representative for realistic SNe, fast time variations of the neutrino signal are easily detectable in IceCube or future megaton-class instruments. We also discuss the information that could be deduced from such a measurement about the physics in the SN core and the explosion mechanism of the SN.Comment: 14 pages, 11 figures. Final version accepted in PRD. Section on astrophysical relevance and several references adde

Biomechanical factors associated with the development of tibiofemoral knee osteoarthritis: protocol for a systematic review and meta-analysis

INTRODUCTION: Altered biomechanics, increased joint loading and tissue damage, might be related in a vicious cycle within the development of knee osteoarthritis (KOA). We have defined biomechanical factors as joint-related factors that interact with the forces, moments and kinematics in and around a synovial joint. Although a number of studies and systematic reviews have been performed to assess the association of various factors with the development of KOA, a comprehensive overview focusing on biomechanical factors that are associated with the development of KOA is not available. The aim of this review is (1) to identify biomechanical factors that are associated with (the development of) KOA and (2) to identify the impact of other relevant risk factors on this association. METHODS AND ANALYSIS: Cohort, cross-sectional and case–control studies investigating the association of a biomechanical factor with (the development of) KOA will be included. MEDLINE, EMBASE, CINAHL and SPORTDiscus will be searched from their inception until August 2015. 2 reviewers will independently screen articles obtained by the search for eligibility, extract data and score risk of bias. Quality of evidence will be evaluated. Meta-analysis using random effects model will be applied in each of the biomechanical factors, if possible. ETHICS AND DISSEMINATION: This systematic review and meta-analysis does not require ethical approval. The results of this systematic review and meta-analysis will be disseminated through publications in peer-reviewed journals and presentations at (inter)national conferences. TRIAL REGISTRATION NUMBER: CRD42015025092

Against research waste – how the evidence-based research paradigm promotes more ethical and innovative research

With notable negative impacts in clinical research, large numbers of studies simply replicate findings that have previously been confirmed. Caroline Blaine, Klara Brunnhuber and Hans Lund, suggest that much of this waste could be averted with a more structured and careful approach to systematic reviews and propose Evidence-Based Research as a framework for achieving this