Growth, profits and technological choice: The case of the Lancashire cotton textile industry

Using Lancashire textile industry company case studies and financial records, mainly from the period just before the First World War, the processes of growth and decline are re-examined. These are considered by reference to the nature of Lancashire entrepreneurship and the impact on technological choice. Capital accumulation, associated wealth distributions and the character of Lancashire business organisation were sybiotically linked to the success of the industry before 1914. However, the legacy of that accumulation in later decades, chronic overcapacity, formed a barrier to reconstruction and enhanced the preciptious decline of a once great industry

Statistical mechanics of an ideal Bose gas in a confined geometry

We study the behaviour of an ideal non-relativistic Bose gas in a three-dimensional space where one of the dimensions is compactified to form a circle. In this case there is no phase transition like that for the case of an infinite volume, nevertheless Bose-Einstein condensation signified by a sudden buildup of particles in the ground state can occur. We use the grand canonical ensemble to study this problem. In particular, the specific heat is evaluated numerically, as well as analytically in certain limits. We show analytically how the familiar result for the specific heat is recovered as we let the size of the circle become large so that the infinite volume limit is approached. We also examine in detail the behaviour of the chemical potential and establish the precise manner in which it approaches zero as the volume becomes large.Comment: 13 pages, 2 eps figures, revtex

One-Loop Renormalization of a Self-Interacting Scalar Field in Nonsimply Connected Spacetimes

Using the effective potential, we study the one-loop renormalization of a massive self-interacting scalar field at finite temperature in flat manifolds with one or more compactified spatial dimensions. We prove that, owing to the compactification and finite temperature, the renormalized physical parameters of the theory (mass and coupling constant) acquire thermal and topological contributions. In the case of one compactified spatial dimension at finite temperature, we find that the corrections to the mass are positive, but those to the coupling constant are negative. We discuss the possibility of triviality, i.e. that the renormalized coupling constant goes to zero at some temperature or at some radius of the compactified spatial dimension.Comment: 16 pages, plain LATE

Effects of polymer additives on Rayleigh-Taylor turbulence

The role of polymers additives on the turbulent convective flow of a Rayleigh--Taylor system is investigated by means of direct numerical simulations (DNS) of Oldroyd-B viscoelastic model. The dynamics of polymers elongation follow adiabatically the self-similar evolution of the turbulent mixing layer, and shows the appearance of a strong feedback on the flow which originate a cut off for polymer elongations. The viscoelastic effects on the mixing properties of the flow are twofold. Mixing is appreciably enhanced at large scales (the mixing layer growth-rate is larger than that of the purely Newtonian case) and depleted at small scales (thermal plumes are more coherent with respect to the Newtonian case). The observed speed up of the thermal plumes, together with an increase of the correlations between temperature field and vertical velocity, contributes to a significant {\it enhancement of heat transport}. Our findings are consistent with a scenario of {\it drag reduction} between falling and rising plumes induced by polymers, and provide further evidence of the occurrence of drag reduction in absence of boundary layers. A weakly non-linear model proposed by Fermi for the growth of the mixing layer is reported in the Appendix.Comment: 19 pages, 12 figure

Bose-Einstein condensation for interacting scalar fields in curved spacetime

We consider the model of self-interacting complex scalar fields with a rigid gauge invariance under an arbitrary gauge group $G$. In order to analyze the phenomenon of Bose-Einstein condensation finite temperature and the possibility of a finite background charge is included. Different approaches to derive the relevant high-temperature behaviour of the theory are presented.Comment: 28 pages, LaTe

Drag Reduction by Polymers in Wall Bounded Turbulence

We address the mechanism of drag reduction by polymers in turbulent wall bounded flows. On the basis of the equations of fluid mechanics we present a quantitative derivation of the "maximum drag reduction (MDR) asymptote" which is the maximum drag reduction attained by polymers. Based on Newtonian information only we prove the existence of drag reduction, and with one experimental parameter we reach a quantitative agreement with the experimental measurements.Comment: 4 pages, 1 fig., included, PRL, submitte

Stress-energy tensor for a quantised bulk scalar field in the Randall-Sundrum brane model

We calculate the vacuum expectation value of the stress-energy tensor for a quantised bulk scalar field in the Randall-Sundrum model, and discuss the consequences of its local behaviour for the self-consistency of the model. We find that, in general, the stress-energy tensor diverges in the vicinity of the branes. Our main conclusion is that the stress-energy tensor is sufficiently complicated that it has implications for the effective potential, or radion stabilisation, methods that have so far been used.Comment: 16 pages, 3 figures. Minor changes made and references added. To appear in Phys. Rev.

Self-management in early-stage dementia: a pilot randomised controlled trial of the efficacy and cost-effectiveness of a self-management group intervention (the SMART study).

Published onlineJournal ArticleRandomized Controlled TrialResearch Support, Non-U.S. Gov'tBACKGROUND: The possibility of living well with a long-term condition has been identified as centrally relevant to the needs of people living with dementia. Growing numbers of people with early-stage dementia are contributing accounts that emphasise the benefits of actively engaging in managing the condition. Self-management interventions share the common objectives of educating about the condition, optimising well-being, enhancing control over the situation and enabling people to take more responsibility for managing the condition. Benefits of such an approach can include improved knowledge, self-efficacy, health status, and better performance of self-management behaviours. However, there is only preliminary evidence that people with early-stage dementia can benefit from such interventions. METHODS: This feasibility study involves the development of a self-management group intervention for people with early-stage Alzheimer's disease, vascular dementia or mixed Alzheimer's and vascular dementia. This study is a single-site pilot randomised-controlled trial. Forty-two people with early stage dementia, each with a caregiver (family member/friend), will be randomised to either the self-management group intervention or to treatment as usual.The self-management group intervention will involve eight weekly sessions, each lasting 90 minutes, held at a memory clinic in North Wales. All participants will be re-assessed three and six months post-randomisation. This study is intended to supply an early evaluation of the self-management intervention so that a full scale trial may be powered from the best available evidence. It will assess the feasibility of the intervention, the study design and the recruitment strategies. It will estimate the parameters and confidence intervals for the research questions of interest. The primary outcome of interest is the self-efficacy score of the person with dementia at three months post-randomisation. Secondary outcomes for the person with dementia are self-efficacy at six months post-randomisation and cognitive ability, mood and well-being at three and six months post-randomisation. Secondary outcomes for caregivers are their distress and stress at three and six months post-randomisation. The cost-effectiveness of the intervention will also be examined. DISCUSSION: This study will provide preliminary information about the feasibility, efficacy and cost-effectiveness of a self-management group intervention for people in the early stages of dementia. TRIAL REGISTRATION: Current Controlled Trials, ISRCTN02023181.NISCHRERDF Ireland Wales Programme 2007–13National Health ServiceHigher Education Funding Council for Wale

Bose-Einstein condensation as symmetry breaking in compact curved spacetimes

We examine Bose-Einstein condensation as a form of symmetry breaking in the specific model of the Einstein static universe. We show that symmetry breaking never occursin the sense that the chemical potential $\mu$ never reaches its critical value.This leads us to some statements about spaces of finite volume in general. In an appendix we clarify the relationship between the standard statistical mechanical approaches and the field theory method using zeta functions.Comment: Revtex, 25 pages, 3 figures, uses EPSF.sty. To be published in Phys. Rev.

Effective Lagrangian for self-interacting scalar field theories in curved spacetime

We consider a self-interacting scalar field theory in a slowly varying gravitational background field. Using zeta-function regularization and heat-kernel techniques, we derive the one-loop effective Lagrangian up to second order in the variation of the background field and up to quadratic terms in the curvature tensors. Specializing to different spacetimes of physical interest, the influence of the curvature on the phase transition is considered.Comment: 14 pages, LaTex, UTF 29