2,065 research outputs found

    bsγb \to s \gamma Decay and Supersymmetry

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    The inclusive radiative BB-decay is a sensitive probe of new physics, especially if related to the virtual exchange of a charged Higgs boson. Supersymmetric models provide a particularly interesting example. In the limit of exact supersymmetry, BR(bsγb \to s\gamma)~=~0, due to the vanishing of any magnetic-moment transition operator. We illustrate the impact of this constraint for realistic values of the supersymmetry-breaking parameters.Comment: 7 pages, CERN-TH.6830/93 (Minor changes; a comment on the case tanβ\tan \beta >1 has been added

    The role of religiousness on substance-use disorder treatment outcomes: a comparison of black and white adolescents

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    This study compares 41 Black and 124 White adolescents at intake and discharge from a residential treatment program for substance-use disorders. Study data were obtained as part of a larger study (N = 195) that sought to assess the relationship of helping behavior and addiction recovery. This post-hoc analysis aims to identify cultural strengths that may be associated with recovery from substance-use disorders among Black adolescents. Using regression analyses and controlling for the severity of substance use and background variables that distinguish racial groups, religious practices and behaviors at intake were examined. Specifically, Black youth and White youth were compared on treatment outcomes, including alcohol or drug use during treatment, drug craving, 12-Step work, and 12-Step helping. The burden of health and socioeconomic disparities at intake did not disproportionately disfavor Black adolescents. Outcomes related to 12-Step measures were similar between Black and White youth. White adolescents reported higher craving scores at discharge, and Black adolescents were more likely to use drugs during treatment. High levels of religiousness at treatment intake were linked to greater 12-Step work and greater 12-Step helping at discharge. High levels of religiousness at intake were not related to drug use during treatment or to craving scores at discharge. The relationship between intake levels of religiousness and treatment-related outcomes did not differ by race.https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3437261/Accepted manuscrip

    Patients presenting to an acute general hospital with acute mental health needs. A retrospective observational cohort study

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    Objectives To examine the numbers and patterns of patients presenting to an urban acute general hospital with acute mental health presentations and to further investigate any variation related to the COVID-19 pandemic. Design Retrospective observational cohort study. Setting An urban acute general hospital in London, UK, comprising of five sites and two emergency departments. The hospital provides tertiary level general acute care but is not an acute mental health services provider. There is an inpatient liaison psychiatry service. Participants 358 131 patients attended the emergency departments of our acute general hospital during the study period. Of these, 14 871 patients attended with an acute mental health presentation. A further 14 947 patients attending with a physical illness were also noted to have a concurrent recorded mental health diagnosis. Results Large numbers of patients present to our acute general hospital with mental health illness even though the organisation does not provide mental health services other than inpatient liaison psychiatry. There was some variation in the numbers and patterns of presentations related to the COVID-19 pandemic. Patient numbers reduced to a mean of 9.13 (SD 3.38) patients presenting per day during the first ‘lockdown’ compared with 10.75 (SD 1.96) patients per day in an earlier matched time period (t=3.80, p<0.01). Acute mental health presentations following the third lockdown increased to a mean of 13.84 a day. Conclusions Large numbers of patients present to our acute general hospital with mental health illness. This suggests a need for appropriate resource, staffing and training to address the needs of these patients in a non-mental health provider organisation and subsequent appropriate transfer for timely treatment. The COVID-19 pandemic and the resulting lockdowns have resulted in variation in the numbers and patterns of patients presenting with acute mental health illness but these presentations are not new. Considerable work is still needed to provide integrated care which addresses the physical and mental healthcare needs of patients presenting to acute and general hospitals

    Efficient HTTP based I/O on very large datasets for high performance computing with the libdavix library

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    Remote data access for data analysis in high performance computing is commonly done with specialized data access protocols and storage systems. These protocols are highly optimized for high throughput on very large datasets, multi-streams, high availability, low latency and efficient parallel I/O. The purpose of this paper is to describe how we have adapted a generic protocol, the Hyper Text Transport Protocol (HTTP) to make it a competitive alternative for high performance I/O and data analysis applications in a global computing grid: the Worldwide LHC Computing Grid. In this work, we first analyze the design differences between the HTTP protocol and the most common high performance I/O protocols, pointing out the main performance weaknesses of HTTP. Then, we describe in detail how we solved these issues. Our solutions have been implemented in a toolkit called davix, available through several recent Linux distributions. Finally, we describe the results of our benchmarks where we compare the performance of davix against a HPC specific protocol for a data analysis use case.Comment: Presented at: Very large Data Bases (VLDB) 2014, Hangzho

    Charge and spin ordering in Nd{1/3}Sr{2/3}FeO{3}

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    We have investigated the charge and spin ordering in Nd{1/3}Sr{2/3}FeO{3} with neutron diffraction technique. This sample undergoes a charge ordering transition accompanying charge disproportionation of 2Fe4+ -> Fe3+ + Fe5+. We measured the superlattice reflections due to the charge and spin ordering, and confirmed that charges and spins order simultaneously at Tco = 185 K. The ordering pattern of charges and spins in this sample can be viewed as three dimensional stripe order, and is compared with two dimensional stripe order observed in other transition metal oxides.Comment: REVTeX, 4 pages, 3 figures, to be published in J. Phys. Chem. Solid

    BRST-anti-BRST Antifield formalism : The Example of the Freedman-Townsend Model

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    The general BRST-anti-BRST construction in the framework of the antifield-antibracket formalism is illustrated in the case of the Freedmann-Townsend model.Comment: 16 pages, Latex file, Latex errors corrected, otherwise unchange

    Partitioning of the global fossil CO2 sink using a 19-year trend in atmospheric O2

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    O2/N2 is measured in the Cape Grim Air Archive (CGAA), a suite of tanks filled with background air at Cape Grim, Tasmania (40.7°S, 144.8°E) between April 1978 and January 1997. Derived trends are compared with published O2/N2 records and assessed against limits on interannual variability of net terrestrial exchanges imposed by trends of δ13C in CO2. Two old samples from 1978 and 1987 and eight from 1996/97 survive critical selection criteria and give a mean 19-year trend in δ(O2/N2) of -16.7 ± 0.5 per meg yr-1, implying net storage of +2.3 ± 0.7 GtC (1015 g carbon) yr-1 of fossil fuel CO2 in the oceans and +0.2 ± 0.9 GtC yr-1 in the terrestrial biosphere. The uptake terms are consistent for both O2/N2 and δ13C tracers if the mean 13C isotopic disequilibrium flux, combining terrestrial and oceanic contributions, is 93 ± 15 GtC ‰ yr-1. Copyright 1999 by the American Geophysical Union

    Spin and orbital ordering in double-layered manganites

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    We study theoretically the phase diagram of the double-layered perovskite manganites taking into account the orbital degeneracy, the strong Coulombic repulsion, and the coupling with the lattice deformation. Observed spin structural changes as the increased doping are explained in terms of the orbital ordering and the bond-length dependence of the hopping integral along cc-axis. Temperature dependence of the neutron diffraction peak corresponding to the canting structure is also explained. Comparison with the 3D cubic system is made.Comment: 7 figure

    A provenance task abstraction framework

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    Visual analytics tools integrate provenance recording to externalize analytic processes or user insights. Provenance can be captured on varying levels of detail, and in turn activities can be characterized from different granularities. However, current approaches do not support inferring activities that can only be characterized across multiple levels of provenance. We propose a task abstraction framework that consists of a three stage approach, composed of (1) initializing a provenance task hierarchy, (2) parsing the provenance hierarchy by using an abstraction mapping mechanism, and (3) leveraging the task hierarchy in an analytical tool. Furthermore, we identify implications to accommodate iterative refinement, context, variability, and uncertainty during all stages of the framework. A use case describes exemplifies our abstraction framework, demonstrating how context can influence the provenance hierarchy to support analysis. The paper concludes with an agenda, raising and discussing challenges that need to be considered for successfully implementing such a framework
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