Personal constructs of mind-body identity in people who experience medically unexplained symptoms (MUS)

"Medically unexplained symptoms" (MUS) refers to chronic physical symptoms without a clear medical cause, which produce significant levels of distress and functional impairment. This project modified the repertory grid technique to explore how twenty participants experiencing MUS construed self and others in bodily and psychological ways. Findings suggested that symptoms are well integrated within participants' wider mind–body construct systems. Increased distance between how self in general is construed compared to self when symptoms are worst was associated with reduced anxiety. Measuring intrapersonal and interpersonal implicative dilemmas suggested that moral and relational construing of identity is affected by MUS.Peer reviewe

Electromagnetism, local covariance, the Aharonov-Bohm effect and Gauss' law

We quantise the massless vector potential A of electromagnetism in the presence of a classical electromagnetic (background) current, j, in a generally covariant way on arbitrary globally hyperbolic spacetimes M. By carefully following general principles and procedures we clarify a number of topological issues. First we combine the interpretation of A as a connection on a principal U(1)-bundle with the perspective of general covariance to deduce a physical gauge equivalence relation, which is intimately related to the Aharonov-Bohm effect. By Peierls' method we subsequently find a Poisson bracket on the space of local, affine observables of the theory. This Poisson bracket is in general degenerate, leading to a quantum theory with non-local behaviour. We show that this non-local behaviour can be fully explained in terms of Gauss' law. Thus our analysis establishes a relationship, via the Poisson bracket, between the Aharonov-Bohm effect and Gauss' law (a relationship which seems to have gone unnoticed so far). Furthermore, we find a formula for the space of electric monopole charges in terms of the topology of the underlying spacetime. Because it costs little extra effort, we emphasise the cohomological perspective and derive our results for general p-form fields A (p < dim(M)), modulo exact fields. In conclusion we note that the theory is not locally covariant, in the sense of Brunetti-Fredenhagen-Verch. It is not possible to obtain such a theory by dividing out the centre of the algebras, nor is it physically desirable to do so. Instead we argue that electromagnetism forces us to weaken the axioms of the framework of local covariance, because the failure of locality is physically well-understood and should be accommodated.Comment: Minor corrections to Def. 4.3, acknowledgements and typos, in line with published versio

Diffusion coefficients for multi-step persistent random walks on lattices

We calculate the diffusion coefficients of persistent random walks on lattices, where the direction of a walker at a given step depends on the memory of a certain number of previous steps. In particular, we describe a simple method which enables us to obtain explicit expressions for the diffusion coefficients of walks with two-step memory on different classes of one-, two- and higher-dimensional lattices.Comment: 27 pages, 2 figure

A randomised controlled trial of long-chain omega-3 polyunsaturated fatty acids in the management of rotator cuff related shoulder pain

Study design Multicentre, double-blind, placebo-controlled randomised clinical trial. Objectives To compare the effectiveness of long chain omega-3 polyunsaturated fatty acids (PUFAs) as part of the management for people diagnosed with rotator cuff related shoulder pain (RCRSP). Summary of background Although there is no robust evidence to support their use, omega-3 PUFAs have been recommended for those with tendinopathy due to their potential to moderate inflammation. Methods Participants with RCRSP (n=73) were randomised to take either nine MaxEPA capsules providing 1.53 g eicosapentaenoic acid, 1.04 g docosahexaenoic acid or nine matching placebo capsules containing oleic acid per day for 8 weeks. In addition, participants attended an exercise/education programme for 8 weeks. Participants were assessed at prerandomisation, 8 weeks (primary outcome point), 3 months, 6 months and 12 months (secondary outcome point). Primary outcome was the Oxford Shoulder Score (OSS). Secondary outcomes included the Shoulder Pain and Disability Index (SPADI), Patient Specific Functional Score, Euro Qol 5D-3L, Short Form 36, global rating of change and impairment measurements. Analysis was by intention to treat. Results Difference in the change in the OSS between the two groups at 2 months was –0.1 (95% CI −2.6 to 2.5, p=0.95). The change in SPADI scores was −8.3 (95% CI −15.6 to −0.94, p=0.03, analysed by analysis of covariance adjusted for baseline) at 3 months. Conclusion Omega-3 PUFA supplementation may have a modest effect on disability and pain outcomes in RCRSP.Peer reviewedFinal Published versio

Measuring logarithmic corrections to normal diffusion in infinite-horizon billiards

We perform numerical measurements of the moments of the position of a tracer particle in a two-dimensional periodic billiard model (Lorentz gas) with infinite corridors. This model is known to exhibit a weak form of super-diffusion, in the sense that there is a logarithmic correction to the linear growth in time of the mean-squared displacement. We show numerically that this expected asymptotic behavior is easily overwhelmed by the subleading linear growth throughout the time-range accessible to numerical simulations. We compare our simulations to the known analytical results for the variance of the anomalously-rescaled limiting normal distributions.Comment: 10 pages, 4 figure