New insights into soft gluons and gravitons

The study of gluon radiation in QCD, in the limit of small ("soft") momentum, remains an active research area, with a variety of phenomenological and theoretical applications. Soft gluon emission leads to large logarithms in perturbation theory which have to be summed up to all orders in the coupling, and also governs the structure of infrared singularities. Recently, new techniques and mathematical structures have been discovered, which enhance our understanding of these all-order properties. This contribution will review a number of key topics, including the relationship between QCD and gravity.Comment: 6 pages, 3 figures; Proceedings of 36th International Conference on High Energy Physics, July 4-11, 2012, Melbourne, Australi

Deconvolution of ASCA X-ray data: I. Spectral-imaging method

In this paper we describe a self-contained method for performing the spectral-imaging deconvolution of X-ray data on clusters of galaxies observed by the ASCA satellite. Spatially-resolved spectral studies of data from this satellite require such a correction because its optics redistribute photons over regions which are of comparable size to the angular scales of interest in clusters. This scattering is a function not only of spatial position but also energy. To perform a correction for these effects we employ Maximum-Likelihood deconvolution of the image (within energy bands of 1 keV) to determine the spatial redistribution, followed by a Monte-Carlo energy reassignment of photon energies with position to determine the spectral redistribution. We present tests on simulated cluster data, convolved with the various instrumental characteristics and the X-ray background, which show that our methodology can successfully recover a variety of intrinsic temperature profiles in typical observational circumstances. In Paper-II we apply our spectral-imaging deconvolution procedure to a large sample of galaxy clusters to determine temperature profiles, some of which will be used in subsequent mass determinations, presented in Paper-III.Comment: MNRAS, accepted. Paper and single page postscript copies of each test's radial profile are available on: http://www-xray.ast.cam.ac.uk/~daw

Recovery from psychosis : physical health, antipsychotic medication and the daily dilemmas for mental health nurses

This paper considers some of the dilemmas experienced by Mental Health Nurses everyday when faced with the seemingly conflicting relationships that exist between recovery, antipsychotics and the physical health of people experiencing psychosis. We examine the role of antipsychotics in the process of recovery from psychosis and argue that Mental Health Nursing’s laudable shift away from the medical model towards the concept of self-defined personal recovery should not result in overlooking the importance of physical health and medication management. Mental Health Nurses have a responsibility to help services users make an informed choice about treatment; this exchange of information should be based on the best available evidence rather than philosophical values or personal opinion

Strategic Trade Policy with Polynomial Costs

 We investigate how the superiority of the optimal subsidy or tariff in an international Cournot oligopoly depends on the production technology used in the industry, an interesting issue that has not been analyzed in the literature. We establish that the welfare superiority of the optimal subsidy or tariff depends on the relative steepness of the firms' common marginal cost curve: when it is relatively steep, tariffs are superior to subsidies in enhancing domestic welfare, and vice versa. When both instruments are used simultaneously, the tariff component becomes more important as the marginal cost curve steepens.