552 research outputs found

    Renormalization and Hyperscaling for Self-Avoiding Manifold Models

    Full text link
    The renormalizability of the self-avoiding manifold (SAM) Edwards model is established. We use a new short distance multilocal operator product expansion (MOPE), which extends methods of local field theories to a large class of models with non-local singular interactions. This validates the direct renormalization method introduced before, as well as scaling laws. A new general hyperscaling relation for the configuration exponent gamma is derived. Manifolds at the Theta-point, and long range Coulomb interactions are briefly discussed.Comment: 10 pages + 1 figure, TeX + harvmac & epsf (uuencoded file), SPhT/93-07

    Renormalization of Crumpled Manifolds

    Get PDF
    We consider a model of D-dimensional tethered manifold interacting by excluded volume in R^d with a single point. By use of intrinsic distance geometry, we first provide a rigorous definition of the analytic continuation of its perturbative expansion for arbitrary D, 0 < D < 2. We then construct explicitly a renormalization operation, ensuring renormalizability to all orders. This is the first example of mathematical construction and renormalization for an interacting extended object with continuous internal dimension, encompassing field theory.Comment: 10 pages (1 figure, included), harvmac, SPhT/92-15

    The poverty of journal publishing

    Get PDF
    The article opens with a critical analysis of the dominant business model of for-profit, academic publishing, arguing that the extraordinarily high profits of the big publishers are dependent upon a double appropriation that exploits both academic labour and universities’ financial resources. Against this model, we outline four possible responses: the further development of open access repositories, a fair trade model of publishing regulation, a renaissance of the university presses, and, finally, a move away from private, for-profit publishing companies toward autonomous journal publishing by editorial boards and academic associations. </jats:p

    Scaling of Selfavoiding Tethered Membranes: 2-Loop Renormalization Group Results

    Full text link
    The scaling properties of selfavoiding polymerized membranes are studied using renormalization group methods. The scaling exponent \nu is calculated for the first time at two loop order. \nu is found to agree with the Gaussian variational estimate for large space dimension d and to be close to the Flory estimate for d=3.Comment: 4 pages, RevTeX + 20 .eps file

    A hisztériával kapcsolatos diskurzusok tanulságai a szomatizációs jelenségek és a betegségmagatartás megértéséhez = The relevance of discourses about hysteria in the understanding of somatization phenomena and illness behaviour

    Get PDF
    Napjainkban a magatartástudományok képviselőinek egyszerre kell számolniuk a betegségekkel kapcsolatos bizonyosság és tudás konfliktusait előhívó medikalizációs-technicizációs orvostudományi tendenciákkal és a társadalomtudományok ezekre reflektáló, kritikai és „posztmodern” megközelítéseivel. Ebből adódóan igen fontos kihívásként jelentkezik az interdiszciplináris megközelítés szükségessége. Különösen így van ez a nehezen definiálható betegségek - a szomatizációs és pszichoszomatikus zavarok - esetében, ahol a betegségmagatartás gyakorlati problémái, továbbá a tünetek, a diagnózisok és a szenvedés „valódiságának” episztemológiai kérdései egyszerre vannak jelen. Az utóbbi másfél évtized kritikai társadalomtudományi kutatásaiban rendkívüli figyelmet kapott a szomatizációs zavarok és a klasszikus pszichoszomatikus kórképek elődjének számító hisztéria kérdésköre. A tanulmány a szakmai és laikus szóhasználatban nem hivatalosan máig tovább élő betegséggel kapcsolatos társadalomtudományi és orvosi megközelítések közül azokat mutatja be, amelyek szempontokkal szolgálhatnak a szomatizációs és pszichoszomatikus kórképek, valamint a velük kapcsolatos érzelmi és viselkedéses reakciók elemzéséhez és megértéséhez

    Which executive functioning deficits are associated with AD/HD, ODD/CD and comorbid AD/HD+ODD/CD?

    Get PDF
    Item does not contain fulltextThis study investigated (1) whether attention deficit/hyperactivity disorder (AD/HD) is associated with executive functioning (EF) deficits while controlling for oppositional defiant disorder/conduct disorder (ODD/CD), (2) whether ODD/CD is associated with EF deficits while controlling for AD/HD, and (3)~whether a combination of AD/HD and ODD/CD is associated with EF deficits (and the possibility that there is no association between EF deficits and AD/HD or ODD/CD in isolation). Subjects were 99~children ages 6–12 years. Three putative domains of EF were investigated using well-validated tests: verbal fluency, working memory, and planning. Independent of ODD/CD, AD/HD was associated with deficits in planning and working memory, but not in verbal fluency. Only teacher rated AD/HD, but not parent rated AD/HD, significantly contributed to the prediction of EF task performance. No EF deficits were associated with ODD/CD. The presence of comorbid AD/HD accounts for the EF deficits in children with comorbid AD/HD+ODD/CD. These results suggest that EF deficits are unique to AD/HD and support the model proposed by R. A. Barkley (1997).17 p

    Bringing the commercial determinants of health out of the shadows : a review of how the commercial determinants are represented in conceptual frameworks

    Get PDF
    BACKGROUND: The term 'commercial determinants of health' (CDOH) is increasingly focussing attention upon the role of tobacco, alcohol and food and beverage companies and others-as important drivers of non-communicable diseases (NCDs). However, the CDOH do not seem to be clearly represented in the most common social determinants of health (SDOH) frameworks. We review a wide range of existing frameworks of the determinants of health to determine whether and how commercial determinants are incorporated into current SDOH thinking. METHODS: We searched for papers and non-academic reports published in English since 2000 describing influences on population health outcomes. We included documents with a formal conceptual framework or diagram, showing the integration of the different determinants. RESULTS: Forty-eight framework documents were identified. Only one explicitly included the CDOH in a conceptual diagram. Ten papers discussed the commercial determinants in some form in the text only and fourteen described negative impacts of commercial determinants in the text. Twelve discussed positive roles for the private sector in producing harmful commodities. Overall, descriptions of commercial determinants are frequently understated, not made explicit, or simply missing. The role of commercial actors as vectors of NCDs is largely absent or invisible in many of the most influential conceptual diagrams. CONCLUSIONS: Our current public health models may risk framing public health problems and solutions in ways that obscure the role that the private sector, in particular large transnational companies, play in shaping the broader environment and individual behaviours, and thus population health outcomes

    Towards an understanding of unique and shared pathways in the psychopathophysiology of AD/HD

    Get PDF
    Most attention deficit hyperactivity disorder (ADHD) research has compared cases with unaffected controls. This has led to many associations, but uncertainties about their specificity to ADHD in contrast with other disorders. We present a selective review of research, comparing ADHD with other disorders in neuropsychological, neurobiological and genetic correlates. So far, a specific pathophysiologicalpathway has not been identified. ADHD is probably not specifically associated with executive function deficits. It is possible, but not yet established, that ADHD symptoms may be more specifically associated with motivational abnormalities, motor organization and time perception. Recent findings indicating common genetic liabilities of ADHD and other conditions raise questions about diagnostic boundaries. In future research, the delineation of the pathophysiological mechanisms of ADHD needs to match cognitive, imaging and genetic techniques to the challenge of defining more homogenous clinical groups; multi-site collaborative projects are needed. © Blackwell Publishing Ltd

    The politics of collective repair: examining object-relations in a postwork society

    Get PDF
    In this article we look at repair as an emergent focus of recent activism in affluent societies, where a number of groups are reclaiming practices of repair as a form of political and ecological action. Ranging from those that fight for legislative change to those groups who are trying to support ecological and social change through everyday life practices, repair is beginning to surface tensions in everyday life and as such poses opportunities for its transformation. We survey a few of the practices that make up this movement in its various articulations, to take stock of their current political import. While we suggest that these practices can be seen as an emergent lifestyle movement, they should not be seen as presenting a unified statement. Rather, we aim to show that they articulate a spectrum of political positions, particularly in relation to the three specific issues of property, pedagogy and sociality. These three dimensions are all facets of current internal discrepancies of repair practices and moreover express potential bifurcations as this movement evolves. Drawing on a diverse methodology that includes discourse analysis and participant observation, we suggest some of the ways in which this growing area of activity could play a significant role in resisting the commodification of the everyday and inventing postwork alternatives
    corecore