Zero-energy states in graphene quantum dots and rings

We present exact analytical zero-energy solutions for a class of smooth decaying potentials, showing that the full confinement of charge carriers in electrostatic potentials in graphene quantum dots and rings is indeed possible without recourse to magnetic fields. These exact solutions allow us to draw conclusions on the general requirements for the potential to support fully confined states, including a critical value of the potential strength and spatial extent.Comment: 8 pages, 3 figures, references added, typos corrected, discussion section expande

An exploratory study of creating dementia-friendly businesses in the visitor economy : Evidence from the UK

© 2019 Published by Elsevier Ltd.Many governments have promoted the development of a civil society to encourage citizen involvement in addressing many of the grand social challenges such as the growing prevalence of dementia, as ageing becomes a major trend in developed societies. One outcome has been the development of Dementia Friendly Communities, created via Dementia Action Alliances (DAAs) in England, to enhance awareness, care and the experience of people with dementia in accessing services and facilities. These initiatives are based on engaging the business community and yet no research studies have examined this theme to date. Given the growing significance of leisure and tourism activities that people with dementia and family members engage in, this study examines the experience of business engagement with DAAs in the visitor economy in England. The notion of shared value articulated by Porter and Kramer (2011) is used as a basis for understanding the type of business engagement.Peer reviewedFinal Published versio

Planetary internal structures

This chapter reviews the most recent advancements on the topic of terrestrial and giant planet interiors, including Solar System and extrasolar objects. Starting from an observed mass-radius diagram for known planets in the Universe, we will discuss the various types of planets appearing in this diagram and describe internal structures for each type. The review will summarize the status of theoretical and experimental works performed in the field of equation of states (EOS) for materials relevant to planetary interiors and will address the main theoretical and experimental uncertainties and challenges. It will discuss the impact of new EOS on interior structures and bulk composition determination. We will discuss important dynamical processes which strongly impact the interior and evolutionary properties of planets (e.g plate tectonics, semiconvection) and describe non standard models recently suggested for our giant planets. We will address the case of short-period, strongly irradiated exoplanets and critically analyse some of the physical mechanisms which have been suggested to explain their anomalously large radius.Comment: 24 pages, 8 figures, Accepted for publication as a chapter in Protostars and Planets VI, University of Arizona Press (2014), eds. H. Beuther, R. Klessen, C. Dullemond, Th. Henning.

Simulating the deep decarbonisation of residential heating for limiting global warming to 1.5C

Whole-economy scenarios for limiting global warming to 1.5C suggest that direct carbon emissions in the buildings sector should decrease to almost zero by 2050, but leave unanswered the question how this could be achieved by real-world policies. We take a modelling-based approach for simulating which policy measures could induce an almost-complete decarbonisation of residential heating, the by far largest source of direct emissions in residential buildings. Under which assumptions is it possible, and how long would it take? Policy effectiveness highly depends on behavioural decision- making by households, especially in a context of deep decarbonisation and rapid transformation. We therefore use the non-equilibrium bottom-up model FTT:Heat to simulate policies for a transition towards low-carbon heating in a context of inertia and bounded rationality, focusing on the uptake of heating technologies. Results indicate that the near-zero decarbonisation is achievable by 2050, but requires substantial policy efforts. Policy mixes are projected to be more effective and robust for driving the market of efficient low-carbon technologies, compared to the reliance on a carbon tax as the only policy instrument. In combination with subsidies for renewables, near-complete decarbonisation could be achieved with a residential carbon tax of 50-200Euro/tCO2. The policy-induced technology transition would increase average heating costs faced by households initially, but could also lead to cost reductions in most world regions in the medium term. Model projections illustrate the uncertainty that is attached to household behaviour for prematurely replacing heating systems

Simulating the impact of the Smith Cloud

We investigate the future evolution of the Smith Cloud by performing hydrodynamical simulations of the cloud impact onto the gaseous Milky Way Galactic disk. We assume a local origin for the cloud and thus do not include a dark matter component to stabilize it. Our main focus is the cloud's influence on the local and global star formation rate (SFR) of the Galaxy and whether or not it leads to an observable event in the far future. Our model assumes two extremes for the mass of the Smith Cloud, an upper mass limit of 10$^7$ M$_{\odot}$ and a lower mass limit of 10$^6$ M$_{\odot}$, compared to the observational value of a few 10$^6$ M$_{\odot}$. In addition, we also make the conservative assumption that the entirety of the cloud mass of the extended Smith Cloud is concentrated within the tip of the cloud. We find that the impact of the low-mass cloud produces no noticeable change in neither the global SFR nor the local SFR at the cloud impact site within the galactic disk. For the high-mass cloud we find a short-term (roughly 5 Myr) increase of the global SFR of up to 1 M$_{\odot}$ yr$^{-1}$, which nearly doubles the normal Milky Way SFR. This highly localized starburst should be observable.Comment: 14 pages, 5 figure

Fast and slow resonant triads in the two layer rotating shallow water equations

In this paper we examine triad resonances in a rotating shallow water system when there are two free interfaces. This allows for an examination in a relatively simple model of the interplay between baroclinic and barotropic dynamics in a context where there is also a geostrophic mode. In contrast to the much-studied one-layer rotating shallow water system, we find that as well as the usual slow geostrophic mode, there are now two fast waves, a barotropic mode and a baroclinic mode. This feature permits triad resonances to occur between three fast waves, with a mixture of barotropic and baroclinic modes, an aspect which cannot occur in the one-layer system. There are now also two branches of the slow geostrophic mode with a repeated branch of the dispersion relation. The consequences are explored in a derivation of the full set of triad interaction equations, using a multi-scale asymptotic expansion based on a small amplitude parameter. The derived nonlinear interaction coefficients are confirmed using energy and enstrophy conservation. These triad interaction equations are explored with an emphasis on the parameter regime with small Rossby and Froude numbers

GPAQ-R: development and psychometric properties of a version of the general practice assessment questionnaire for use for revalidation by general practitioners in the UK.

BACKGROUND: The General Practice Assessment Questionnaire (GPAQ) has been widely used to assess patient experience in general practice in the UK since 2004. In 2013, new regulations were introduced by the General Medical Council (GMC) requiring UK doctors to undertake periodic revalidation, which includes assessment of patient experience for individual doctors. We describe the development of a new version of GPAQ - GPAQ-R which addresses the GMC's requirements for revalidation as well as additional NHS requirements for surveys that GPs may need to carry out in their own practices. METHODS: Questionnaires were given out by doctors or practice staff after routine consultations in line with the guidance given by the General Medical Council for surveys to be used for revalidation. Data analysis and practice reports were provided independently. RESULTS: Data were analysed for questionnaires from 7258 patients relating to 164 GPs in 29 general practices. Levels of missing data were generally low (typically 4.5-6%). The number of returned questionnaires required to achieve reliability of 0.7 were around 35 for individual doctor communication items and 29 for a composite score based on doctor communication items. This suggests that the responses to GPAQ-R had similar reliability to the GMC's own questionnaire and we recommend 30 completed GPAQ-R questionnaires are sufficient for revalidation purposes. However, where an initial screen raises concern, the survey might be repeated with 50 completed questionnaires in order to increase reliability. CONCLUSIONS: GPAQ-R is a development of a well-established patient experience questionnaire used in general practice in the UK since 2004. This new version can be recommended for use in order to meet the UK General Medical Council's requirements for surveys to be used in revalidation of doctors. It also meets the needs of GPs to ask about patient experience relating to aspects of practice care that are not specific to individual general practitioners (e.g. receptionists, telephone access) which meet other survey requirements of the National Health Service in England. Use of GPAQ-R has the potential to reduce the number of surveys that GPs need to carry out in their practices to meet the various regulatory requirements which they face

A variational principle for fluid sloshing with vorticity, dynamically coupled to vessel motion

A variational principle is derived for two-dimensional incompressible rotational fluid flow with a free surface in a moving vessel when both the vessel and fluid motion are to be determined. The fluid is represented by a stream function and the vessel motion is represented by a path in the planar Euclidean group. Novelties in the formulation include how the pressure boundary condition is treated, the introduction of a stream function into the Euler-Poincar\'e variations, the derivation of free surface variations, and how the equations for the vessel path in the Euclidean group, coupled to the fluid motion, are generated automatically.Comment: 19 pages, 3 figure

British pain clinic practitioners' recognition and use of the bio-psychosocial pain management model for patients when physical interventions are ineffective or inappropriate : results of a qualitative study

Background To explore how chronic musculoskeletal pain is managed in multidisciplinary pain clinics for patients for whom physical interventions are inappropriate or ineffective. Methods A qualitative study was undertaken using semi-structured interviews with twenty five members of the pain management team drawn from seven pain clinics and one pain management unit located across the UK. Results All clinics reported using a multidisciplinary bio-psychosocial model. However the chronic pain management strategy actually focussed on psychological approaches in preference to physical approaches. These approaches were utilised by all practitioners irrespective of their discipline. Consideration of social elements such as access to social support networks to support patients in managing their chronic pain was conspicuously absent from the approaches used. Conclusion Pain clinic practitioners readily embraced cognitive/behavioural based management strategies but relatively little consideration to the impact social factors played in managing chronic pain was reported. Consequently multidisciplinary pain clinics espousing a bio-psychosocial model of pain management may not be achieving their maximum potential

Selecting and implementing overview methods: implications from five exemplar overviews

This is the final version of the article. Available from BioMed Central via the DOI in this record.Background Overviews of systematic reviews are an increasingly popular method of evidence synthesis; there is a lack of clear guidance for completing overviews and a number of methodological challenges. At the UK Cochrane Symposium 2016, methodological challenges of five overviews were explored. Using data from these five overviews, practical implications to support methodological decision making of authors writing protocols for future overviews are proposed. Methods Methods, and their justification, from the five exemplar overviews were tabulated and compared with areas of debate identified within current literature. Key methodological challenges and implications for development of overview protocols were generated and synthesised into a list, discussed and refined until there was consensus. Results Methodological features of three Cochrane overviews, one overview of diagnostic test accuracy and one mixed methods overview have been summarised. Methods of selection of reviews and data extraction were similar. Either the AMSTAR or ROBIS tool was used to assess quality of included reviews. The GRADE approach was most commonly used to assess quality of evidence within the reviews. Eight key methodological challenges were identified from the exemplar overviews. There was good agreement between our findings and emerging areas of debate within a recent published synthesis. Implications for development of protocols for future overviews were identified. Conclusions Overviews are a relatively new methodological innovation, and there are currently substantial variations in the methodological approaches used within different overviews. There are considerable methodological challenges for which optimal solutions are not necessarily yet known. Lessons learnt from five exemplar overviews highlight a number of methodological decisions which may be beneficial to consider during the development of an overview protocol.The overview conducted by Pollock [19] was supported by a project grant from the Chief Scientist Office of the Scottish Government. The overview conducted by McClurg [21] was supported by a project grant by the Physiotherapy Research Foundation. The overview by Hunt [22] was supported as part of doctoral programme funding by the National Institute for Health Research (NIHR) Collaboration for Leadership in Applied Health Research and Care South West Peninsula (PenCLAHRC). The overview conducted by Estcourt [20] was supported by an NIHR Cochrane Programme Grant for the Safe and Appropriate Use of Blood Components. The overview conducted by Brunton [23] was commissioned by the Department of Health as part of an ongoing programme of work on health policy research synthesis. Alex Pollock is employed by the Nursing, Midwifery and Allied Health Professions (NMAHP) Research Unit, which is supported by the Chief Scientist Office of the Scottish Government. Pauline Campbell is supported by the Chief Nurses Office of the Scottish Government