High transients suppressed in electromagnetic devices

A bifilar winding around the magnetic core of electromagnetic devices suppresses high transient voltages. The winding is alternately spaced vertically and radially from the core to achieve a high coefficient of coupling

'TIDieR-ing up' the reporting of interventions in stroke research:The importance of knowing what is in the 'black box'

Evidence-based interventions cannot be provided unless there is a clear understanding of what the intervention is. Many published randomized trials, systematic reviews, and guidelines contain incomplete intervention descriptions. For non-pharmacological interventions, such as stroke rehabilitation, the reporting is particularly poor. Contributors to this problem include lack of attention to this issue and awareness of what constitutes a complete intervention description by authors, reviewers, journals, and editors. Part of the solution is for authors to follow guidance about how to describe interventions, such as the Template for Intervention Description and Replication statement. Improving stroke interventions reporting will remove one of the current barriers to evidence-based care. </jats:p

Decision aids for randomised controlled trials : a qualitative exploration of stakeholders' views

Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions. Funding: This work was supported by personal fellowship award (to KG) from the Chief Scientist Office of the Scottish Governments Health and Social Care Directorates, grant number [PDF/09/01]. The Health Services Research Unit is supported by a core grant from the Chief Scientist Office of the Scottish Government Health and Social Care Directorates.Peer reviewedPublisher PD

Physics of SNeIa and Cosmology

We give an overview of the current understanding of Type Ia supernovae relevant for their use as cosmological distance indicators. We present the physical basis to understand their homogeneity of the observed light curves and spectra and the observed correlations. This provides a robust method to determine the Hubble constant, 67 +- 8 (2 sigma) km/Mpc/sec, independently from primary distance indicators. We discuss the uncertainties and tests which include SNe Ia based distance determinations prior to delta-Ceph. measurements for the host galaxies. Based on detailed models, we study the small variations from homogeneities and their observable consequences. In combination with future data, this underlines the suitability and promises the refinements needed to determine accurate relative distances within 2 to 3 % and to use SNe Ia for high precision cosmology.Comment: to be published in "Stellar Candles", eds. Gieren et al. Lecture Notes in Physics (http://link.springer.de/series/lnpp

Vegetable Forcing in Ohio

PDF pages: 3

Evidence Against an Association Between Gamma-Ray Bursts and Type I Supernovae

We present a rigorous method, based on Bayesian inference, for calculating the odds favoring the hypothesis that any particular class of astronomical transients produce gamma-ray bursts over the hypothesis that they do not. We then apply this method to a sample of 83 Type Ia supernovae and a sample of 20 Type Ib-Ic supernovae. We find overwhelming odds against the hypothesis that all Type Ia supernovae produce gamma-ray bursts, whether at low redshift ($10^{9}:1$) or high-redshift ($10^{12}:1$), and very large odds ($6000:1$) against the hypothesis that all Type Ib, Ib/c, and Ic supernovae produce observable gamma-ray bursts. We find large odds ($34:1$) against the hypothesis that a fraction of Type Ia supernovae produce observable gamma-ray bursts, and moderate odds ($6:1$) against the hypothesis that a fraction of Type Ib-Ic supernovae produce observable bursts. We have also re-analyzed both a corrected version of the Wang & Wheeler sample of Type Ib-Ic SNe and our larger sample of 20 Type Ib-Ic SNe, using a generalization of their frequentist method. We find no significant evidence in either case of a correlation between Type Ib-Ic SNe and GRBs, consistent with the very strong evidence against such a correlation that we find from our Bayesian analysis.Comment: 45 pages, 2 PostScript figures. Uses AASTEX macros. Submitted to The Astrophysical Journa

Investigating the relationship between predictability and imbalance in minimisation : a simulation study

Peer reviewedPublisher PD

Strengthening the ethical assessment of placebo-controlled surgical trials : three proposals

Peer reviewedPublisher PD

Attractors of directed graph IFSs that are not standard IFS attractors and their Hausdorff measure

For directed graph iterated function systems (IFSs) defined on R, we prove that a class of 2-vertex directed graph IFSs have attractors that cannot be the attractors of standard (1-vertex directed graph) IFSs, with or without separation conditions. We also calculate their exact Hausdorff measure. Thus we are able to identify a new class of attractors for which the exact Hausdorff measure is known