The Database of Abstracts of Reviews of Effects (DARE)

Systematic reviews are useful tools for busy decision-makers because they identify, appraise and synthesise the available research evidence on a particular topic. Many thousands of systematic reviews relevant to health care have been published. However, they can be difficult to locate and their quality is variable. DARE (the Database of Abstracts of Reviews of Effects) contains summaries of systematic reviews which have met strict quality criteria. Each summary also provides a critical commentary on the quality of the review. DARE covers a broad range of health care related topics and can be used for answering questions about the effects of health care interventions, as well as for developing clinical guidelines and policy making. DARE is available free of charge on the internet (http://nhscrd.york.ac.uk), and as part of the Cochrane Library. Alternatively, DARE can be searched, on your behalf, by CRD information staff (tel: 01904 433707 or email [email protected])

Hopf instantons, Chern-Simons vortices, and Heisenberg ferromagnets

The dimensional reduction of the three-dimensional fermion-Chern-Simons model (related to Hopf maps) of Adam et el. is shown to be equivalent to (i) either the static, fixed--chirality sector of our non-relativistic spinor-Chern-Simons model in 2+1 dimensions, (ii) or a particular Heisenberg ferromagnet in the plane.Comment: 4 pages, Plain Tex, no figure

Information Services in the CGIAR

Paper by the TAC Standing Committee for External Reviews, drawing on the consultant paper by John Woolston, and several inputs from the CGIAR Secretariat concerning the role of information in the CGIAR. It argues for the centers to play a role in the development and use of a more coherent global information system for research in agriculture, forestry, and fisheries. The NARS should in the long term be able to participate in such a system as full fledged actors. The paper urges the CGIAR to take the lead in organizing a conference on global information needs and opportunities.Agenda document, TAC 56

Do research studies in the UK reporting child neurodevelopment adjust for the variability of assessors:a systematic review

AIM: Neurodevelopment is a key outcome for many childhood trials and observational studies. Clinically important decisions may rest on finding relatively small differences in neurodevelopment between groups receiving complex and costly interventions. Our purpose was to determine whether studies which measure neurodevelopment report the numbers, training, and auditing of assessors and, for multiple assessor studies, whether the results were adjusted and if so by which method?METHOD: Electronic searches were conducted using Medline, Embase, Cinahl, PsycINFO, and the Cochrane Library. A study was eligible if it reported neurodevelopmental outcome in children resident in the UK, less than or equal to 18 years and was published between 2000 and 2015. Trials and observational studies were included.RESULTS: Three hundred and seven full papers were reviewed: 52% of papers did not report the number of assessors used; 21% used a single assessor; and 27% used multiple assessors. Thirty-five per cent mentioned that assessors were trained in the use of the neurodevelopmental tool; 13% of assessors were audited; and only 1% of studies adjusted statistically for the number of assessors.INTERPRETATION: At the very least, the quality of reporting the use of assessors in these research publications is poor, while at worst, the variability of assessors may mask the true relationship between an intervention/observation and neurodevelopmental outcome.</p

Quantum Hall effect anomaly and collective modes in the magnetic-field-induced spin-density-wave phases of quasi-one-dimensional conductors

We study the collective modes in the magnetic-field-induced spin-density-wave (FISDW) phases experimentally observed in organic conductors of the Bechgaard salts family. In phases that exhibit a sign reversal of the quantum Hall effect (Ribault anomaly), the coexistence of two spin-density waves gives rise to additional collective modes besides the Goldstone modes due to spontaneous translation and rotation symmetry breaking. These modes strongly affect the charge and spin response functions. We discuss some experimental consequences for the Bechgaard salts.Comment: Final version (LaTex, 8 pages, no figure), to be published in Europhys. Let

Critical Exponents of the Three Dimensional Random Field Ising Model

The phase transition of the three--dimensional random field Ising model with a discrete ($\pm h$) field distribution is investigated by extensive Monte Carlo simulations. Values of the critical exponents for the correlation length, specific heat, susceptibility, disconnected susceptibility and magnetization are determined simultaneously via finite size scaling. While the exponents for the magnetization and disconnected susceptibility are consistent with a first order transition, the specific heat appears to saturate indicating no latent heat. Sample to sample fluctuations of the susceptibilty are consistent with the droplet picture for the transition.Comment: Revtex, 10 pages + 4 figures included as Latex files and 1 in Postscrip

A Study of Activated Processes in Soft Sphere Glass

On the basis of long simulations of a binary mixture of soft spheres just below the glass transition, we make an exploratory study of the activated processes that contribute to the dynamics. We concentrate on statistical measures of the size of the activated processes.Comment: 17 pages, 9 postscript figures with epsf, uses harvmac.te

Conformal Enhancement of Holographic Scaling in Black Hole Thermodynamics: A Near-Horizon Heat-Kernel Framework

Standard thermodynamic treatments of quantum field theory in the presence of black-hole backgrounds reproduce the black hole entropy by usually specializing to the leading order of the heat-kernel or the high-temperature expansion. By contrast, this work develops a hybrid framework centered on geometric spectral asymptotics whereby these assumptions are shown to be unwarranted insofar as black hole thermodynamics is concerned. The approach--consisting of the concurrent use of near-horizon and heat-kernel asymptotic expansions--leads to a proof of the holographic scaling of the entropy as a universal feature driven by conformal quantum mechanics.Comment: 13 pages, JHEP style. Added section 3 in the new version and a few typos were correcte

Factorization of the Two Loop Four-Particle Amplitude in Superstring Theory Revisited

We study in detail the factorization of the newly obtained two-loop four-particle amplitude in superstring theory. In particular some missing factors from the scalar correlators are obtained correctly, in comparing with a previous study of the factorization in two-loop superstring theory. Some details for the calculation of the factorization of the kinematic factor are also presented.Comment: 11 pages, 1 figure; v2, minor corrections and references update