5,719 research outputs found

    Absolute continuity and spectral concentration for slowly decaying potentials

    Get PDF
    We consider the spectral function ρ(μ)\rho(\mu) (μ0)(\mu \geq 0) for the Sturm-Liouville equation y+(λq)y=0y^{''}+(\lambda-q)y =0 on [0,)[0,\infty) with the boundary condition y(0)=0y(0)=0 and where qq has slow decay O(xα)O(x^{-\alpha}) (a>0)(a>0) as xx\to \infty. We develop our previous methods of locating spectral concentration for qq with rapid exponential decay (JCAM 81 (1997) 333-348) to deal with the new theoretical and computational complexities which arise for slow decay

    Extensions of a New Algorithm for the Numerical Solution of Linear Differential Systems on an Infinite Interval

    Full text link
    This paper is part of a series of papers in which the asymptotic theory and appropriate symbolic computer code are developed to compute the asymptotic expansion of the solution of an n-th order ordinary differential equation. The paper examines the situation when the matrix that appears in the Levinson expansion has a double eigenvalue. Application is made to a fourth-order ODE with known special function solution

    Screening for health risks: A social science perspective

    Get PDF
    Health screening promises to reduce risks to individuals via probabilistic sifting of populations for medical conditions. The categorisation and selection of 'conditions' such as cardiovascular events, dementia and depression for screening itself requires prior interpretive labour which usually remains unexamined. Screening systems can take diverse organisational forms and varying relationships to health status, as when purported disease precursors, for example 'pre-cancerous' polyps, or supposed risk factors, such as high cholesterol themselves, become targets for screening. Screening at best yields small, although not necessarily unworthwhile, net population health gains. It also creates new risks, leaving some individuals worse-off than if they had been left alone. The difficulties associated with attempting to measure small net gains through randomised controlled trials are sometimes underestimated. Despite endemic doubts about its clinical utility, bibliometric analysis of published papers shows that responses to health risks are coming to be increasingly thought about in terms of screening. This shift is superimposed on a strengthening tendency to view health through the lens of risk. It merits further scrutiny as a societal phenomenon

    Alcohol and healthy ageing: a challenge for alcohol policy

    Get PDF
    Objectives: This paper presents findings of a qualitative study of older people's use of alcohol during retirement and identifies ways that an improved understanding of older people's drinking can inform policy approaches to alcohol and active and healthy ageing. Study design: Qualitative semi-structured interviews conducted with a self-selecting sample of retired people. Methods: Participants were recruited from three geographical locations in the West of Scotland. A quota sampling design was used to ensure a broad spread of participants in terms of socio-economic position, age and gender. In total 40 participants were interviewed and the data analysed thematically using Braun and Clarke's (2006) approach. Results: Amongst those who used alcohol, it was most often framed in terms of pleasure, relaxation, socialising and as a way to mark the passage of time. Alcohol was often associated with social occasions and interactions both in private and in public spaces. There were also many examples of the use of imposed routines to limit alcohol use and of a decreasing volume of alcohol being consumed as participants aged. This suggests that older people are often active in constructing what they regard as ‘healthier’ routines around alcohol use. However, processes and circumstances associated with ageing can lead to risk of social isolation and/or increased alcohol consumption. Such processes include retirement from paid work and other ‘biographical disruptions’ such as caring for a partner, bereavement and/or loss of social networks. Conclusions: These findings highlight processes that can result in changes in drinking habits and routines. Whilst these processes can be associated with a reduction or cessation of alcohol use as people age, they can also be associated with increased risk of harmful alcohol consumption. Fractured or disrupted routines, particularly those associated with bereavement or the burden of caring responsibilities, through increasing the risk of loneliness and isolation, can construct increased risk of harmful alcohol consumption. These findings reframe the pathway of risk between ageing and alcohol-related harm by highlighting the vulnerability to harmful drinking practices brought by fracture or sudden change of routine. The findings point to a role for public health in supporting the reconstruction of routines that provide structure and meaning and can be used to actively manage the benefits and harms associated with drinking

    Building a future...An exploration of the contribution of educational provision to clients’ well-being at Southwark Day Centre for Asylum Seekers

    Get PDF
    This research project builds on previous work, ‘Beneath the Surface’ (Cogo, Inman, McCormack, Rogers 2018) which focussed on how clients at Southwark Day Centre for Asylum Seekers (SDCAS) understood and evaluated their well-being. One of the areas touched on in that research was the role of educational activities in developing the well-being of clients. This report describes in depth the ways in which the educational provision offered in the centre contributes to the well-being of clients and how this contribution might be enhanced. The report focuses on two areas of education provision; gardening and storytelling and explains how they contribute to the well-being of the clients. The interview data confirms that the activities in these two areas help to build clients’ psychological, physical and social resources and have a positive effect on how clients feel and how they function in the world. The report ends with recommendations as to how SDCAS might ensure that gardening and storytelling continue to benefit the well-being of clients and also as to what might be put in place to strengthen the activities

    Critical Current Peaks at 3BΦ3B_{\Phi} in Superconductors with Columnar Defects: Recrystalizing the Interstitial Glass

    Full text link
    The role of commensurability and the interplay of correlated disorder and interactions on vortex dynamics in the presence of columnar pins is studied via molecular dynamics simulations. Simulations of dynamics reveal substantial caging effects and a non-monotonic dependence of the critical current with enhancements near integer values of the matching field BϕB_{\phi} and 3Bϕ3B_{\phi} in agreement with experiments on the cuprates. We find qualitative differences in the phase diagram for small and large values of the matching field.Comment: 5 pages, 4 figures (3 color

    Stories from lockdown: the impact of the Covid19 pandemic on the well-being of clients at Southwark Day Centre for Asylum Seekers (SDCAS)

    Get PDF
    The report describes the findings of research on how the Covid 19 related lockdowns affected the well-being of clients at the Southwark Day Centre for Asylum Seekers. A small number of clients were interviewed about the practical issues of housing, food, money and about their physical and mental health during the periods of lockdowns. They were also asked about support from the Southwark Day Centre for Asylum Seekers. The report describes the experiences of these clients between March 2020 and March 202
    corecore