Higher Dimensional Coulomb Gases and Renormalized Energy Functionals

We consider a classical system of n charged particles in an external confining potential, in any dimension d larger than 2. The particles interact via pairwise repulsive Coulomb forces and the coupling parameter scales like the inverse of n (mean-field scaling). By a suitable splitting of the Hamiltonian, we extract the next to leading order term in the ground state energy, beyond the mean-field limit. We show that this next order term, which characterizes the fluctuations of the system, is governed by a new "renormalized energy" functional providing a way to compute the total Coulomb energy of a jellium (i.e. an infinite set of point charges screened by a uniform neutralizing background), in any dimension. The renormalization that cuts out the infinite part of the energy is achieved by smearing out the point charges at a small scale, as in Onsager's lemma. We obtain consequences for the statistical mechanics of the Coulomb gas: next to leading order asymptotic expansion of the free energy or partition function, characterizations of the Gibbs measures, estimates on the local charge fluctuations and factorization estimates for reduced densities. This extends results of Sandier and Serfaty to dimension higher than two by an alternative approach.Comment: Structure has slightly changed, details and corrections have been added to some of the proof

The Effects of Brief Mindfulness Strategy on Craving, Affect and Alcohol Consumption

Background: Recent theories of addiction emphasise craving and negative affect as the central mechanisms that underpin alcohol abuse. Mindfulness-based interventions have been suggested to increase people’s ability to manage craving and negative affect, and thereby reduce the habitual reaction of drinking as a result of the unpleasant feelings. Aim: To examine the effect of brief mindfulness training on craving, affect and alcohol consumption, in comparison to brief relaxation training. Method: Sixty-eight participants were randomly allocated to brief mindfulness or relaxation training. Participants underwent cue-reactivity procedures before and after the training. Dependent variables included subjective and physiological measures of craving and affect, and alcohol consumption at 7-day follow-up. Results: Both mindfulness and relaxation reduced subjective cue-induced craving and arousal levels, as well as craving at follow-up. No effects were seen on pleasure during the cue-reactivity procedure. Mindfulness was also associated with a significant reduction in alcohol consumption at follow-up. The reduction in drinking in the mindfulness group was associated with acutely increased cue-induced physiological arousal. Conclusions: The results support the notion that both mindfulness and relaxation can reduce craving and arousal during cue-reactivity, but only mindfulness can reduce alcohol consumption at follow-up. This study also offers insights regarding physiological arousal, being a potential mechanism involved in the reduction in drinking

Mindfulness, Acceptance and Defusion Strategies in Smokers: a Systematic Review of Laboratory Studies

The psychological flexibility model (PFM) provides a framework for understanding and treating behavioural dysregulation in addictions. Rather than modulating the intensity of subjective experience, interventions based on, or consistent with, the PFM (PFM interventions) seek to alter the individual’s relationship to internal states, such as craving, negative affect and drug-related thoughts, using mindfulness, acceptance and related strategies. Experimental (non-clinical) studies in smokers have examined the effects of specific isolated strategies informed by or consistent with the PFM (PFM strategies). Here, we systematically review these studies and determine the extent to which they conform to methodological standards indicative of high levels of internal validity. Eligible studies were identified through electronic database searches and assessed for the presence of specific methodological features. Provisional aggregate effect sizes were determined depending on availability of data. Of 1499 screened publications, 12 met the criteria. All examined aspects of private subjective experience relevant to abstinence (craving n = 12; negative affect n = 10), demonstrating effects favouring PFM strategies relative to inactive control conditions. However, only six assessed outcome domains consistent with the PFM and provided no consistent evidence favouring PFM strategies. Overall, most studies had methodological limitations. As such, high-quality experimental studies continue to be needed to improve our understanding of necessary and/or sufficient constituents of PFM-guided smoking cessation interventions. Recommendations for future research are discussed

Ginzburg-Landau vortex dynamics with pinning and strong applied currents

We study a mixed heat and Schr\"odinger Ginzburg-Landau evolution equation on a bounded two-dimensional domain with an electric current applied on the boundary and a pinning potential term. This is meant to model a superconductor subjected to an applied electric current and electromagnetic field and containing impurities. Such a current is expected to set the vortices in motion, while the pinning term drives them toward minima of the pinning potential and "pins" them there. We derive the limiting dynamics of a finite number of vortices in the limit of a large Ginzburg-Landau parameter, or \ep \to 0, when the intensity of the electric current and applied magnetic field on the boundary scale like \lep. We show that the limiting velocity of the vortices is the sum of a Lorentz force, due to the current, and a pinning force. We state an analogous result for a model Ginzburg-Landau equation without magnetic field but with forcing terms. Our proof provides a unified approach to various proofs of dynamics of Ginzburg-Landau vortices.Comment: 48 pages; v2: minor errors and typos correcte

Renormalized energy concentration in random matrices

We define a "renormalized energy" as an explicit functional on arbitrary point configurations of constant average density in the plane and on the real line. The definition is inspired by ideas of [SS1,SS3]. Roughly speaking, it is obtained by subtracting two leading terms from the Coulomb potential on a growing number of charges. The functional is expected to be a good measure of disorder of a configuration of points. We give certain formulas for its expectation for general stationary random point processes. For the random matrix $\beta$-sine processes on the real line (beta=1,2,4), and Ginibre point process and zeros of Gaussian analytic functions process in the plane, we compute the expectation explicitly. Moreover, we prove that for these processes the variance of the renormalized energy vanishes, which shows concentration near the expected value. We also prove that the beta=2 sine process minimizes the renormalized energy in the class of determinantal point processes with translation invariant correlation kernels.Comment: last version, to appear in Communications in Mathematical Physic

Delivering cognitive behavioural therapy to advanced cancer patients: A qualitative exploration into therapists' experiences within a UK psychological service

BACKGROUND: Cognitive behavioural therapy (CBT) is commonly used to treat cancer patients with psychological disorders such as depression. There has been little qualitative research exploring the experience of therapists delivering CBT to patients with advanced cancer and long-term health conditions generally. Therapists' views may help identify difficulties in delivering therapy and how these may be overcome. The aim of this study was to inform practice by qualitatively exploring the experiences of therapists delivering CBT to patients with advanced cancer. DESIGN: Sixteen semi-structured interviews were conducted with therapists from Increasing Access to Psychological Therapy (IAPT) services in London, UK, who had delivered CBT to patients enrolled on the CanTalk trial. Interviews were recorded, transcribed, and analysed using framework analysis. RESULTS: Therapists reported positive experiences when working with the target population. Flexibility, adaptability, and a consideration of individual needs were identified as important when delivering CBT, but the rigidity of IAPT policies and demand for services were perceived as problematic. Although therapists reported adequate training, specialist supervision was desired when delivering therapy to this complex population. CONCLUSION: IAPT therapists can deliver CBT to advanced cancer patients, given therapists positive experiences evident in the present study. However, it was concluded that additional service and modifications of therapy may be needed before positive outcomes for both therapists and patients can be achieved

Cognitive behaviour therapy (CBT) for anxiety and depression in adults with mild intellectual disabilities (ID): a pilot randomised controlled trial

Background: Several studies have showed that people with intellectual disabilities (ID) have suitable skills to undergo cognitive behavioural therapy (CBT). Case studies have reported successful use of cognitive behavioural therapy techniques (with adaptations) in people with ID. Modified cognitive behavioural therapy may be a feasible and effective approach for the treatment of depression, anxiety, and other mood disorders in ID. To date, two studies have reported group-based manaulised cognitive behavioural treatment programs for depression in people with mild ID. However, there is no individual manualised programme for anxiety or depression in people with intellectual disabilities. The aims of the study are to determine the feasibility of conducting a randomised controlled trial for CBT in people with ID. The data will inform the power calculation and other aspects of carrying out a definitive randomised controlled trial.Methods: Thirty participants with mild ID will be allocated randomly to either CBT or treatment as usual (TAU). The CBT group will receive up to 20 hourly individual CBT over a period of 4 months. TAU is the standard treatment which is available to any adult with an intellectual disability who is referred to the intellectual disability service (including care management, community support, medical, nursing or social support). Beck Youth Inventories (Beck Anxiety Inventory & Beck Depression Inventory) will be administered at baseline; end of treatment (4 months) and at six months to evaluate the changes in depression and anxiety. Client satisfaction, quality of life and the health economics will be secondary outcomes.Discussion: The broad outcome of the study will be to produce clear guidance for therapists to apply an established psychological intervention and identify how and whether it works with people with intellectual disabilities

Effectiveness of cognitive-behavioural therapy for depression in advanced cancer: CanTalk randomised controlled trial

BACKGROUND: Depression is one of the most common mental disorders in people with advanced cancer. Although cognitive-behavioural therapy (CBT) has been shown to be effective for depression in people with cancer, it is unclear whether this is the case for people with advanced cancer and depression. // AIMS: We sought to determine whether CBT is more clinically effective than treatment as usual (TAU) for treating depression in people with advanced cancer (trial registration number ISRCTN07622709). // METHOD: A multi-centre, parallel-group single-blind randomised controlled trial comparing TAU with CBT (plus TAU). Participants (n = 230) with advanced cancer and depression were randomly allocated to (a) up to 12 sessions of individual CBT or (b) TAU. The primary outcome measure was the Beck Depression Inventory-II (BDI-II). Secondary outcome measures included the Patient Health Questionnaire-9, the Eastern Cooperative Oncology Group Performance Status, and Satisfaction with Care. // RESULTS: Multilevel modelling, including complier-average intention-to-treat analysis, found no benefit of CBT. CBT delivery was proficient, but there was no treatment effect (-0.84, 95% CI -2.76 to 1.08) or effects for secondary measures. Exploratory subgroup analysis suggested an effect of CBT on the BDI-II in those widowed, divorced or separated (-7.21, 95% CI -11.15 to -3.28). // CONCLUSIONS: UK National Institute for Health and Care Excellence (NICE) guidelines recommend CBT for treating depression. Delivery of CBT through the Improving Access to Psychological Therapies (IAPT) programme has been advocated for long-term conditions such as cancer. Although it is feasible to deliver CBT through IAPT proficiently to people with advanced cancer, this is not clinically effective. CBT for people widowed, divorced or separated needs further exploration. Alternate models of CBT delivery may yield different results. // DECLARATION OF INTEREST: M.S. is a member of the Health Technology Assessment General Board

Vortex density models for superconductivity and superfluidity

We study some functionals that describe the density of vortex lines in superconductors subject to an applied magnetic field, and in Bose-Einstein condensates subject to rotational forcing, in quite general domains in 3 dimensions. These functionals are derived from more basic models via Gamma-convergence, here and in a companion paper. In our main results, we use these functionals to obtain descriptions of the critical applied magnetic field (for superconductors) and forcing (for Bose-Einstein), above which ground states exhibit nontrivial vorticity, as well as a characterization of the vortex density in terms of a non local vector-valued generalization of the classical obstacle problem.Comment: 34 page

Acceptance and commitment therapy for adults with advanced cancer (CanACT): study protocol for a feasibility randomised controlled trial

BACKGROUND: One-third of people with cancer experience psychological distress and may suppress distressing thoughts, emotions, and concerns, leading to further problems. Conventional psychological treatments reduce distress by problem solving, but in advanced cancer, when ill health is progressive and death may be approaching, physical and psychological difficulties are complex and have no simple solutions. Acceptance and Commitment Therapy encourages acknowledgement and acceptance of mental experiences, increasing people's ability to work with problems that cannot be solved. Previous pilot work in advanced cancer confirms that distress can be associated with an avoidance of experiencing uncomfortable thoughts and emotions. METHODS/DESIGN: This feasibility randomised controlled trial of Acceptance Commitment Therapy aims to establish parameters for a larger trial. Fifty-four participants with advanced cancer will be randomly allocated to up to eight sessions (each 1 hour) of Acceptance Commitment Therapy or a talking control. Participants will be recruited from those attending outpatient services and hospice day care at three specialist palliative care units in North and East London, United Kingdom. The primary outcome is a measure of functioning in four areas of life (physical, social/family, emotional, and general activity) using the Functional Assessment of Cancer Therapies - General questionnaire at 3 months after randomisation. Secondary outcomes are (i) acceptance using the Acceptance and Action Questionnaire; (ii) psychological distress using the Kessler Psychological Distress Scale; (iii) physical functioning using a timed walk and sit-to-stand test; and (iv) quality of life measures including the Euroqol-5 Dimensions and ICECAP Supportive Care measures. Qualitative data will be collected at 3 months to explore the participants' experiences of the trial and therapy. Data will be collected on the costs of care. DISCUSSION: Data generated on the recruitment, retention, and experience of the interventions and the usefulness of the outcome measures will inform the adaptations required and whether changes in function are consistent with existing data when planning for a sufficiently powered randomised controlled trial. TRIAL REGISTRATION: ISRCTN13841211 (registered 22 July 2015)