On the Renormalization of Theories of a Scalar Chiral Superfield

An exact renormalization group for theories of a scalar chiral superfield is formulated, directly in four dimensional Euclidean space. By constructing a projector which isolates the superpotential from the full Wilsonian effective action, it is shown that the nonperturbative nonrenormalization theorem follows, quite simply, from the flow equation. Next, it is argued that there do not exist any physically acceptable non-trivial fixed points. Finally, the Wess-Zumino model is considered, as a low energy effective theory. Following an evaluation of the one and two loop beta-function coefficients, to illustrate the ease of use of the formalism, it is shown that the beta-function in the massless case does not receive any nonperturbative power corrections.Comment: 52 pages, 4 figures; v2: 57 pages - refs added and some minor corrections/clarifications made; v3: published in JHEP - some further clarifications mad

A thematic analysis of barriers and facilitators to participant engagement in group exposure and response prevention therapy for obsessive-compulsive disorder

Exposure and response prevention (ERP) is the gold standard in the treatment of the obsessive-compulsive disorder (OCD). It can be delivered effectively using an individual or group therapy format. Nonetheless, a sizeable proportion of people diagnosed with OCD do not experience OCD symptom remission following ERP. Research suggests that participant engagement with ERP tasks predicts therapy outcomes but there is little consistent evidence across studies on what predicts engagement. A recent meta-analysis of participant engagement in cognitive-behavioral therapy for OCD found that group ERP had a comparatively lower dropout rate than individual ERP. Little is known about participant perceptions of ERP to guide an understanding of how the group therapy format may affect participant engagement. This study conducted a qualitative exploration of what helps or hinders participants' engagement in group ERP. It involved thematic analysis of semi-structured interview data collected at a 6-month follow-up from 15 adults with OCD who took part in group ERP. The study identified five main themes that captured participants' perceived facilitators and barriers to engagement in therapy: 'Group processes', 'Understanding how to overcome OCD', 'Personal relevance', 'Personal circumstances', and 'Attitudes towards ERP', which captured dynamically inter-related barriers and facilitators at the level of the client, therapist, therapy and social environment. Each theme and associated sub-themes are discussed in turn, followed by a consideration of the study's limitations and implications

The brightness clustering transform and locally contrasting keypoints

In recent years a new wave of feature descriptors has been presented to the computer vision community, ORB, BRISK and FREAK amongst others. These new descriptors allow reduced time and memory consumption on the processing and storage stages of tasks such as image matching or visual odometry, enabling real time applications. The problem is now the lack of fast interest point detectors with good repeatability to use with these new descriptors. We present a new blob- detector which can be implemented in real time and is faster than most of the currently used feature-detectors. The detection is achieved with an innovative non-deterministic low-level operator called the Brightness Clustering Transform (BCT). The BCT can be thought as a coarse-to- fine search through scale spaces for the true derivative of the image; it also mimics trans-saccadic perception of human vision. We call the new algorithm Locally Contrasting Keypoints detector or LOCKY. Showing good repeatability and robustness to image transformations included in the Oxford dataset, LOCKY is amongst the fastest affine-covariant feature detectors

Four methods for determining the composition of trace radioactive surface contamination of low-radioactivity metal

Four methods for determining the composition of low-level uranium- and thorium-chain surface contamination are presented. One method is the observation of Cherenkov light production in water. In two additional methods a position-sensitive proportional counter surrounding the surface is used to make both a measurement of the energy spectrum of alpha particle emissions and also coincidence measurements to derive the thorium-chain content based on the presence of short-lived isotopes in that decay chain. The fourth method is a radiochemical technique in which the surface is eluted with a weak acid, the eluate is concentrated, added to liquid scintillator and assayed by recording beta-alpha coincidences. These methods were used to characterize two `hotspots' on the outer surface of one of the He-3 proportional counters in the Neutral Current Detection array of the Sudbury Neutrino Observatory experiment. The methods have similar sensitivities, of order tens of ng, to both thorium- and uranium-chain contamination.Comment: 22 pages, 19 figure

Low-intensity guided help through mindfulness (LIGHTMIND): study protocol for a randomised controlled trial comparing supported mindfulness-based cognitive therapy self-help to supported cognitive behavioural therapy self-help for adults experiencing depression

Background: Depression has serious personal, family and economic consequences. It is estimated that it will cost £12.15 billion to the economy each year in England by 2026. Improving Access to Psychological Therapies (IAPT) is the National Health Service talking therapies service in England for adults experiencing anxiety or depression. Over 1 million people are referred to IAPT every year, over half experiencing depression. Where symptoms of depression are mild/moderate, people are typically offered Cognitive Behavioural Therapy (CBT) self-help supported by a psychological wellbeing practitioner (PWP). The problem is that over half of people who complete treatment for depression in IAPT remain depressed despite receiving National Institute of Health and Care Excellent (NICE) recommended treatment. Furthermore, less than half of IAPT service users complete treatment. This study seeks to investigate the effectiveness of an alternative to CBT self-help. Mindfulness-based cognitive therapy differs from CBT in focus, approach and practice and may be more effective with a higher number of treatment completions. Methods/Design: This is a definitive randomised controlled trial comparing supported mindfulness-based cognitive therapy self-help (MBCT-SH) with supported cognitive behavioural therapy self-help (CBT-SH) for adults experiencing mild/moderate depression being treated in IAPT services. Four hundred and ten participants experiencing mild/moderate depression will be recruited from IAPT services and randomised to receive either an MBCT-based self-help workbook or a CBT-based self-help workbook. Participants will be asked to complete their workbook within 16 weeks, with six support sessions with a PWP. The primary outcome is depression symptom severity upon treatment completion. Secondary outcomes are treatment completion rates and measures of generalized anxiety, wellbeing, functioning and mindfulness. An exploratory non-inferiority analysis will be conducted in the event the primary hypothesis is not supported. A semi-structured interview with participants will guide understanding of change processes. Discussion: If the findings from this randomised controlled trial demonstrate that MBCT-SH is more effective than CBT-SH for adults experiencing depression, this will provide evidence for policy makers and lead to changes to clinical practice in IAPT services, leading to greater choice of self-help treatment options and better outcomes for service users. If the exploratory non-inferiority analysis is conducted and this indicates non-inferiority of MBCT-SH in comparison to CBT-SH this will also be of interest to policy makers when seeking to increase service user choice of self-help treatment options for depression. Trial registration: Current Controlled Trial registration number ISRCTN 13495752. Registered on 31 August 2017 (www.isrctn.com/ISRCTN13495752). Protocol Version: Version 1 (18 January 2020) Recruitment Status: Recruiting: participants are currently being recruited and enrolled Date first participant randomised: 24 November 2017 Trial Sponsor: Sussex Partnership NHS Foundation Trust ([email protected]

Clinical effectiveness and cost-effectiveness of supported mindfulness-based cognitive therapy self-help compared with supported cognitive behavioral therapy self-help for adults experiencing depression: The low-intensity guided help through mindfulness (LIGHTMind) randomized clinical trial

Importance Depression is prevalent. Treatment guidelines recommend practitioner-supported cognitive behavioral therapy self-help (CBT-SH) for mild to moderate depression in adults; however, dropout rates are high. Alternative approaches are required. Objective To determine if practitioner-supported mindfulness-based cognitive therapy self-help (MBCT-SH) is superior to practitioner-supported CBT-SH at reducing depressive symptom severity at 16 weeks postrandomization among patients with mild to moderate depression and secondarily to examine if practitioner-supported MBCT-SH is cost-effective compared with practitioner-supported CBT-SH. Design, Setting, and Participants This was an assessor- and participant-blinded superiority randomized clinical trial with 1:1 automated online allocation stratified by center and depression severity comparing practitioner-supported MBCT-SH with practitioner-supported CBT-SH for adults experiencing mild to moderate depression. Recruitment took place between November 24, 2017, and January 31, 2020. The study took place in 10 publicly funded psychological therapy services in England (Improving Access to Psychological Therapies [IAPT]). A total of 600 clients attending IAPT services were assessed for eligibility, and 410 were enrolled. Participants met diagnostic criteria for mild to moderate depression. Data were analyzed from January to October 2021. Interventions Participants received a copy of either an MBCT-SH or CBT-SH workbook and were offered 6 support sessions with a trained practitioner. Main Outcomes and Measures The preregistered primary outcome was Patient Health Questionnaire (PHQ-9) score at 16 weeks postrandomization. The primary analysis was intention-to-treat with treatment arms masked. Results Of 410 randomized participants, 255 (62.2%) were female, and the median (IQR) age was 32 (25-45) years. At 16 weeks postrandomization, practitioner-supported MBCT-SH (n = 204; mean [SD] PHQ-9 score, 7.2 [4.8]) led to significantly greater reductions in depression symptom severity compared with practitioner-supported CBT-SH (n = 206; mean [SD] PHQ-9 score, 8.6 [5.5]), with a between-group difference of −1.5 PHQ-9 points (95% CI, −2.6 to −0.4; P = .009; d = −0.36). The probability of MBCT-SH being cost-effective compared with CBT-SH exceeded 95%. However, although between-group effects on secondary outcomes were in the hypothesized direction, they were mostly nonsignificant. Three serious adverse events were reported, all deemed not study related. Conclusions and Relevance In this randomized clinical trial, practitioner-supported MBCT-SH was superior to standard recommended treatment (ie, practitioner-supported CBT-SH) for mild to moderate depression in terms of both clinical effectiveness and cost-effectiveness. Findings suggest that MBCT-SH for mild to moderate depression should be routinely offered to adults in primary care services. Trial Registration isrctn.org Identifier: ISRCTN1349575

Chiral phase boundary of QCD at finite temperature

We analyze the approach to chiral symmetry breaking in QCD at finite temperature, using the functional renormalization group. We compute the running gauge coupling in QCD for all temperatures and scales within a simple truncated renormalization flow. At finite temperature, the coupling is governed by a fixed point of the 3-dimensional theory for scales smaller than the corresponding temperature. Chiral symmetry breaking is approached if the running coupling drives the quark sector to criticality. We quantitatively determine the phase boundary in the plane of temperature and number of flavors and find good agreement with lattice results. As a generic and testable prediction, we observe that our underlying IR fixed-point scenario leaves its imprint in the shape of the phase boundary near the critical flavor number: here, the scaling of the critical temperature is determined by the zero-temperature IR critical exponent of the running coupling.Comment: 39 pages, 8 figure

A Manifestly Gauge Invariant and Universal Calculus for SU(N) Yang-Mills

Within the framework of the Exact Renormalization Group, a manifestly gauge invariant calculus is constructed for SU(N) Yang-Mills. The methodology is comprehensively illustrated with a proof, to all orders in perturbation theory, that the beta function has no explicit dependence on either the seed action or details of the covariantization of the cutoff. The cancellation of these non-universal contributions is done in an entirely diagrammatic fashion.Comment: 128 pages, 89 figures; v2: published in ijmpa - intro extended, refs added, refinements and minor corrections made; v3 small corrections made compared to published versio

Low-Intensity Guided Help Through Mindfulness (LIGHTMIND): study protocol for a randomised controlled trial comparing supported mindfulness-based cognitive therapy self-help to supported cognitive behavioural therapy self-help for adults experiencing depression

Background Depression has serious personal, family and economic consequences. It is estimated that it will cost £12.15 billion to the economy each year in England by 2026. Improving access to psychological therapies (IAPT) is the National Health Service talking therapies service in England for adults experiencing anxiety or depression. Over 1 million people are referred to IAPT every year, over half experiencing depression. Where symptoms of depression are mild to moderate, people are typically offered cognitive behavioural therapy (CBT) self-help (CBT-SH) supported by a psychological well-being practitioner. The problem is that over half of people who complete treatment for depression in IAPT remain depressed despite receiving National Institute of Health and Care Excellent recommended treatment. Furthermore, less than half of IAPT service users complete treatment. This study seeks to investigate the effectiveness of an alternative to CBT-SH. Mindfulness-based cognitive therapy (MBCT) differs from CBT in focus, approach and practice, and may be more effective with a higher number of treatment completions. Methods/design This is a definitive randomised controlled trial comparing supported MBCT self-help (MBCT-SH) with CBT-SH for adults experiencing mild to moderate depression being treated in IAPT services. We will recruit 410 participants experiencing mild to moderate depression from IAPT services and randomise these to receive either an MBCT-based self-help workbook or a CBT-based self-help workbook. Participants will be asked to complete their workbook within 16 weeks, with six support sessions with a psychological well-being practitioner. The primary outcome is depression symptom severity on treatment completion. Secondary outcomes are treatment completion rates and measures of generalized anxiety, well-being, functioning and mindfulness. An exploratory non-inferiority analysis will be conducted in the event the primary hypothesis is not supported. A semi-structured interview with participants will guide understanding of change processes. Discussion If the findings from this randomised controlled trial demonstrate that MBCT-SH is more effective than CBT-SH for adults experiencing depression, this will provide evidence for policy makers and lead to changes to clinical practice in IAPT services, leading to greater choice of self-help treatment options and better outcomes for service users. If the exploratory non-inferiority analysis is conducted and this indicates non-inferiority of MBCT-SH in comparison to CBT-SH this will also be of interest to policy makers when seeking to increase service user choice of self-help treatment options for depression. Trial registration Current Controlled Trial registration number: ISRCTN 13495752. Registered on 31 August 2017 (www.isrctn.com/ISRCTN13495752)