7,416 research outputs found

    Heavy Quark Physics From Lattice QCD

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    We review the application of lattice QCD to the phenomenology of b- and c-quarks. After a short discussion of the lattice techniques used to evaluate hadronic matrix elements and the corresponding systematic uncertainties, we summarise results for leptonic decay constants, B--Bbar mixing, semileptonic and rare radiative decays. A discussion of the determination of heavy quark effective theory parameters is followed by an explanation of the difficulty in applying lattice methods to exclusive nonleptonic decays.Comment: 52 pages LaTeX with 10 eps files. Requires: hfsprocl.sty (included) plus axodraw.sty, rotating.sty and array.sty. To appear in Heavy Flavours (2nd edition) edited by A J Buras and M Lindner (World Scientific, Singapore). Revised version corrects typo in axis labelling of Fig 1

    Assessing the Effectiveness of Automated Emotion Recognition in Adults and Children for Clinical Investigation

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    Recent success stories in automated object or face recognition, partly fuelled by deep learning artificial neural network (ANN) architectures, has led to the advancement of biometric research platforms and, to some extent, the resurrection of Artificial Intelligence (AI). In line with this general trend, inter-disciplinary approaches have taken place to automate the recognition of emotions in adults or children for the benefit of various applications such as identification of children emotions prior to a clinical investigation. Within this context, it turns out that automating emotion recognition is far from being straight forward with several challenges arising for both science(e.g., methodology underpinned by psychology) and technology (e.g., iMotions biometric research platform). In this paper, we present a methodology, experiment and interesting findings, which raise the following research questions for the recognition of emotions and attention in humans: a) adequacy of well-established techniques such as the International Affective Picture System (IAPS), b) adequacy of state-of-the-art biometric research platforms, c) the extent to which emotional responses may be different among children or adults. Our findings and first attempts to answer some of these research questions, are all based on a mixed sample of adults and children, who took part in the experiment resulting into a statistical analysis of numerous variables. These are related with, both automatically and interactively, captured responses of participants to a sample of IAPS pictures

    In situ aerosol measurements taken during the 2007 COPS field campaign at the Hornisgrinde ground site

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    Copyright @ 2011 Royal Meteorological Society.The Convective and Orographically-induced Precipitation Study (COPS) campaign was conducted during the summer of 2007. A suite of instruments housed at the top of the Hornisgrinde Mountain (1156 m) in the Black Forest region of south-west Germany provided datasets that allow an investigation into the physical, chemical and hygroscopic properties of the aerosol particles sampled during COPS. Organic mass loadings were found to dominate the aerosol composition for the majority of the project, exceeding 8 µg m−3 during a period of high pressure, high temperature, and low wind speed. The ratio of organic:sulphate sub-micron mass concentration exceeds 10:1 during the same time period. Back trajectories show air from this time-frame passing slowly over the local forest and not passing over any local anthropogenic sources. Occasional peaks in nitrate mass loadings were associated with changes in the typical wind direction from south-westerly to north-westerly where air had passed over the Stuttgart region. Size distribution data shows a dominant accumulation-mode when the measurement site was free from precipitation events. A sharp increase in ultrafine particle number concentration was seen during most days commencing around noon. The apparent growth of these particles is associated with an increase in organic mass loading, suggesting condensational growth. For the most part, with the exception of the high pressure period, the aerosol properties recorded during COPS were comparable to previous studies of continental aerosol properties.NER

    Bayesian inference for form-factor fits regulated by unitarity and analyticity

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    We propose a model-independent framework for fitting hadronic form-factor data, which is often only available at discrete kinematical points, using parameterisations based on to unitarity and analyticity. In this novel approach the latter two properties of quantum-field theory regulate the ill-posed fitting problem and allow model-independent predictions over the entire physical range. Kinematical constraints, for example for the vector and scalar form factors in semileptonic meson decays, can be imposed exactly. The core formulae are straight-forward to implement with standard math libraries. We take account of a generalisation of the original Boyd~Grinstein~Lebed (BGL) unitarity constraint for form factors and demonstrate our method for the exclusive semileptonic decay BsKνB_s\to K \ell \nu, for which we make a number of phenomenologically relevant predictions, including the CKM matrix element Vub|V_{ub}|.Comment: 45 pages, 8 figures, references added, typos fixe

    Preventing and responding to depression, self-harm, and suicide in older people living in long term care settings: a systematic review

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    Abstract Objective: The well documented demographic shift to an aging population means that more people will in future be in need of long term residential care. Previous research has reported an increased risk of mental health issues and suicidal ideation among older people living in residential care settings. However, there is little information on the actual prevalence of depression, self-harm, and suicidal behavior in this population, how it is measured and how care homes respond to these issues. Method: This systematic review of international literature addressed three research questions relating to; the prevalence of mental health problems in this population; how they are identified and; how care homes try to prevent or respond to mental health issues. Results: Findings showed higher reported rates of depression and suicidal behavior in care home residents compared to matched age groups in the community, variation in the use of standardised measures across studies and, interventions almost exclusively focused on increasing staff knowledge about mental health but with an absence of involvement of older people themselves in these programmes. Conclusion: We discuss the implications of these findings in the context of addressing mental health difficulties experienced by older people in residential care and future research in this area

    Ultrafast control of inelastic tunneling in a double semiconductor quantum

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    In a semiconductor-based double quantum well (QW) coupled to a degree of freedom with an internal dynamics, we demonstrate that the electronic motion is controllable within femtoseconds by applying appropriately shaped electromagnetic pulses. In particular, we consider a pulse-driven AlxGa1-xAs based symmetric double QW coupled to uniformly distributed or localized vibrational modes and present analytical results for the lowest two levels. These predictions are assessed and generalized by full-fledged numerical simulations showing that localization and time-stabilization of the driven electron dynamics is indeed possible under the conditions identified here, even with a simultaneous excitations of vibrational modes.Comment: to be published in Appl.Phys.Let

    Heavy quark mass dependence of semileptonic form factors for B decays

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    We present our study of the dependence of the heavy-to-light semileptonic B decay form factors on the heavy-light meson mass MPSM_{PS}. Simulations are made over a range of the heavy quark mass covering both the charm and bottom quarks using the O(a)O(a)-improved clover action at β=5.9\beta=5.9 on a 163×4016^3\times 40 and 243×6424^3\times 64 lattice. We find that a weak dependence of form factors on MPSM_{PS} observed in previous studies in the region of charm quark persists up to the region ofbb quark. The soft pion relation f0(qmax2)=fB/fπf^0(q^2_{max})=f_B/f_\pi is examined and found to be largely violated.Comment: 3 pages, latex source-file, 4 figures as epsf-file, uses espcrc2.sty. Talk presented by S. Tominaga at Lattice 97, Edinburgh, Scotland, 22-26 Jul 199

    SNS programming environment user's guide

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    The computing environment is briefly described for the Supercomputing Network Subsystem (SNS) of the Central Scientific Computing Complex of NASA Langley. The major SNS computers are a CRAY-2, a CRAY Y-MP, a CONVEX C-210, and a CONVEX C-220. The software is described that is common to all of these computers, including: the UNIX operating system, computer graphics, networking utilities, mass storage, and mathematical libraries. Also described is file management, validation, SNS configuration, documentation, and customer services

    Development of a self-report measure of capability wellbeing for adults: the ICECAP-A

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    Purpose The benefits of health and social care are not confined to patient health alone and therefore broader measures of wellbeing may be useful for economic evaluation.\ud This paper reports the development of a simple measure of capability wellbeing for adults (ICECAP-A).\ud Methods In-depth, informant-led, interviews to identify the attributes of capability wellbeing were conducted with 36 adults in the UK. Eighteen semi-structured, repeat interviews were carried out to develop a capability-based descriptive system for the measure. Informants were purposively selected to ensure variation in socio-economic status, age, sex, ethnicity and health. Data analysis was carried out inductively and iteratively alongside interviews, and findings were used to shape the questions in later interviews.\ud Results Five over-arching attributes of capability wellbeing were identified for the measure: ‘‘stability’’,‘‘attachment’’, ‘‘achievement’’, ‘‘autonomy’’ and ‘‘enjoyment’’. One item, with four response categories, was developed for each attribute for the ICECAP-A descriptive system.\ud Conclusions The ICECAP-A capability measure represents a departure from traditional health economics outcome measures, by treating health status as an influence over broader attributes of capability wellbeing. Further work is required to value and validate the attributes and test the sensitivity of the ICECAP-A to healthcare interventions

    Heavy Hadron Spectroscopy

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    I review recent theoretical advances in heavy hadron spectroscopy.Comment: Plenary talk at the XXXIII International Conference on High Energy Physics (ICHEP 06), Moscow, Russia, July 26 - August 2, 2006; 11 page
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