171 research outputs found

    Distribution of Energy-Momentum in a Schwarzschild-Quintessence Space-time Geometry

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    An analysis of the energy-momentum localization for a four-dimensional\break Schwarzschild black hole surrounded by quintessence is presented in order to provide expressions for the distributions of energy and momentum. The calculations are performed by using the Landau-Lifshitz and Weinberg energy-momentum complexes. It is shown that all the momenta vanish, while the expression for the energy depends on the mass MM of the black hole, the state parameter wqw_{q} and the normalization factor cc. The special case of wq=2/3w_{q}=-2/3 is also studied, and two limiting cases are examined.Comment: 9 page

    Towards Canonical Quantum Gravity for G1 Geometries in 2+1 Dimensions with a Lambda--Term

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    The canonical analysis and subsequent quantization of the (2+1)-dimensional action of pure gravity plus a cosmological constant term is considered, under the assumption of the existence of one spacelike Killing vector field. The proper imposition of the quantum analogues of the two linear (momentum) constraints reduces an initial collection of state vectors, consisting of all smooth functionals of the components (and/or their derivatives) of the spatial metric, to particular scalar smooth functionals. The demand that the midi-superspace metric (inferred from the kinetic part of the quadratic (Hamiltonian) constraint) must define on the space of these states an induced metric whose components are given in terms of the same states, which is made possible through an appropriate re-normalization assumption, severely reduces the possible state vectors to three unique (up to general coordinate transformations) smooth scalar functionals. The quantum analogue of the Hamiltonian constraint produces a Wheeler-DeWitt equation based on this reduced manifold of states, which is completely integrated.Comment: Latex 2e source file, 25 pages, no figures, final version (accepted in CQG

    Energy-Momentum Localization for a Space-Time Geometry Exterior to a Black Hole in the Brane World

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    In general relativity one of the most fundamental issues consists in defining a generally acceptable definition for the energy-momentum density. As a consequence, many coordinate-dependent definitions have been presented, whereby some of them utilize appropriate energy-momentum complexes. We investigate the energy-momentum distribution for a metric exterior to a spherically symmetric black hole in the brane world by applying the Landau-Lifshitz and Weinberg prescriptions. In both the aforesaid prescriptions, the energy thus obtained depends on the radial coordinate, the mass of the black hole and a parameter λ0\lambda_{0}, while all the momenta are found to be zero. It is shown that for a special value of the parameter λ0\lambda_{0}, the Schwarzschild space-time geometry is recovered. Some particular and limiting cases are also discussed.Comment: 10 pages, sections 1 and 3 slightly modified, references modified and adde

    Enhancing employability and engagement with the university through the Student Experience Leaders (SEL) scheme

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    The University of Bedfordshire launched a new Education and Student Experience Strategy (2022-2026) that includes expanding students as partners opportunities as a key priority. The Student Experience Leaders (SEL) scheme was launched in 2022 and is managed by the Learning Development Team at the University of Bedfordshire in partnership with the Students’ Union. SEL provides opportunities for students to work with course teams and professional service staff to deliver curricular and co-/extra-curricular projects (aligned to key strategic priorities). SELs also act as representatives for Course Reps within faculties to champion the student voice. We believe that the formal representation partnership co-led by the Students’ Union and Learning Development Team differentiates our scheme from more traditional Peer Assisted Learning schemes. Our approach, therefore, contributes to the wider learning development field in terms of redefining how learning development teams could co-lead students as partners initiatives within their institution. Approximately 30 students have been recruited to the SEL scheme, which consists of nine projects from four faculties and two directorates. The SELs received training on various identified key transferable skills from the Learning Development Team and Students’ Union to support them in their roles. The Learning Development Team have also established and facilitated a community of practices for SELs. The first round of the scheme will conclude in June 2023 and will be evaluated through a narrative-focused and empirical evaluation using a mixed-methods approach. Pre- and post-questionnaires that focus on the transferable skills of SELs and focus group interviews will provide data for evaluation. This session considered the role of a Learning Development Team in leading a student as partners institutional scheme. We discussed how the SEL scheme will inform the future delivery of learning development at the University. We also considered how to best support students as partners in their role and how a learning development team can be effectively promoted through such activity

    Eligibility for interventions, co-occurrence and risk factors for unhealthy behaviours in patients consulting for routine primary care: results from the Pre-Empt study

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    Smoking, excessive drinking, lack of exercise and a poor diet remain key causes of premature morbidity and mortality globally, yet it is not clear what proportion of patients attending for routine primary care are eligible for interventions about these behaviours, the extent to which they co-occur within individuals, and which individuals are at greatest risk for multiple unhealthy behaviours. The aim of the trial was to examine 'intervention eligibility' and co-occurrence of the 'big four' risky health behaviours - lack of exercise, smoking, an unhealthy diet and excessive drinking - in a primary care population. Data were collected from adult patients consulting routinely in general practice across South Wales as part of the Pre-Empt study; a cluster randomised controlled trial. After giving consent, participants completed screening instruments, which included the following to assess eligibility for an intervention based on set thresholds: AUDIT-C (for alcohol), HSI (for smoking), IPAQ (for exercise) and a subset of DINE (for diet). The intervention following screening was based on which combination of risky behaviours the patient had. Descriptive statistics, χ2 tests for association and ordinal regressions were undertaken. Two thousand sixty seven patients were screened: mean age of 48.6 years, 61.9 % female and 42.8 % in a managerial or professional occupation. In terms of numbers of risky behaviours screened eligible for, two was the most common (43.6 %), with diet and exercise (27.2 %) being the most common combination. Insufficient exercise was the most common single risky behaviour (12.0 %). 21.8 % of patients would have been eligible for an intervention for three behaviours and 5.9 % for all four behaviours. Just 4.5 % of patients did not identify any risky behaviours. Women, older age groups and those in managerial or professional occupations were more likely to exhibit all four risky behaviours. Very few patients consulting for routine primary care screen ineligible for interventions about common unhealthy behaviours, and most engage in more than one of the major common unhealthy behaviours. Clinicians should be particularly alert to opportunities to engaging younger, non professional men and those with multi-morbidity about risky health behaviour. ISRCTN22495456. BACKGROUND METHODS RESULTS CONCLUSION TRIAL REGISTRATIO

    Towards Canonical Quantum Gravity for Geometries Admitting Maximally Symmetric Two-dimensional Surfaces

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    The 3+1 (canonical) decomposition of all geometries admitting two-dimensional space-like surfaces is exhibited. A proposal consisting of a specific re-normalization {\bf Assumption} and an accompanying {\bf Requirement} is put forward, which enables the canonical quantization of these geometries. The resulting Wheeler-deWitt equation is based on a re-normalized manifold parameterized by three smooth scalar functionals. The entire space of solutions to this equation is analytically given, exploiting the freedom left by the imposition of the {\bf Requirement} and contained in the third functional.Comment: 27 pages, no figures, LaTex2e source fil

    Effectiveness of Motivational Interviewing in improving lipid level in patients with dyslipidemia assisted by general practitioners: Dislip-EM study protocol

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    <p>Abstract</p> <p>Background</p> <p>The non-pharmacological approach to cholesterol control in patients with hyperlipidemia is based on the promotion of a healthy diet and physical activity. Thus, to help patients change their habits, it is essential to identify the most effective approach. Many efforts have been devoted to explain changes in or adherence to specific health behaviors. Such efforts have resulted in the development of theories that have been applied in prevention campaigns, and that include brief advice and counseling services. Within this context, Motivational Interviewing has proven to be effective in changing health behaviors in specific cases. However, more robust evidence is needed on the effectiveness of Motivational Interviewing in treating chronic pathologies -such as dyslipidemia- in patients assisted by general practitioners. This article describes a protocol to assess the effectiveness of MI as compared with general practice (brief advice), with the aim of improving lipid level control in patients with dyslipidemia assisted by a general practitioner.</p> <p>Methods/Design</p> <p>An open, two-arm parallel, multicentre, cluster, controlled, randomized, clinical trial will be performed. A total of 48-50 general practitioners from 35 public primary care centers in Spain will be randomized and will recruit 436 patients with dyslipidemia. They will perform an intervention based either on Motivational Interviewing or on the usual brief advice. After an initial assessment, follow-ups will be performed at 2, 4, 8 and 12 months. Primary outcomes are lipid levels (total cholesterol, HDL cholesterol, LDL cholesterol, triglycerides) and cardiovascular risk. The study will assess the degree of dietary and physical activity improvement, weight loss in overweight patients, and adherence to treatment guidelines.</p> <p>Discussion</p> <p>Motivational interview skills constitute the primary strategies GPs use to treat their patients. Having economical, simple, effective and applicable techniques is essential for primary care professionals to help their patients change their lifestyle and improve their health. This study will provide scientific evidence on the effectiveness of Motivational interviewing, and will be performed under strict control over the data collected, ensuring the maintenance of therapeutic integrity.</p> <p>Trials Registration</p> <p>ClinicalTrials.gov (<a href="http://www.clinicaltrials.gov/ct2/show/NCT01282190">NCT01282190</a>).</p

    Clientelism and corruption: Institutional adaptation of state capture strategies in view of resource scarcity in Greece

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    How do strategies of state capture adapt to tight fiscal conditions? The article uses a historical institutionalist approach and content analysis to study the case of Greece. Three theoretically relevant patterns of institutional adaptation are unearthed: first, limited resources for state capture do indeed trigger self-limitation initiatives as expected, but these initiatives replace costly benefits with less costly ones. Second, different forms of capture have different implications for the terms of political competition. Third, there is a mutually reinforcing relationship between clientelism and corruption, which becomes pronounced in the creative ways by which strategies of capture adjust to shifting opportunities and constraints. Clients are appointed in state offices and extract bribes directly from citizens. ‘Client corruption’ replaces extraction from the state with extraction through the state, which is less costly for the public finances: the benefit the governing party gives to its clients is the ‘right’ to extract rents for themselves

    From the Sum of Near-Zero Energy Buildings to the Whole of a Near-Zero Energy Housing Settlement: The Role of Communal Spaces in Performance-Driven Design

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    Almost a century ago Modernism challenged the structure of the city and reshaped its physical space in order to, amongst other things, accommodate new transportation infrastructure and road networks proclaiming the,nowadays much-debated ‘scientificated’ pursuit of efficiency for the city. This transformation has had a great impact on the way humans still design, move in, occupy and experience the city. Today major cities in Europe, such as Paris and London, are considering banning vehicles from their historic centers. In parallel, significant effort is currently underway internationally by designers, architects, and engineers to integrate innovative technologies and sophisticated solutions for energy production, management, and storage, as well as for efficient energy consumption, into the architecture of buildings. In general, this effort seeks for new technologies and design methods (e.g., DesignBuilder with EnergyPlus simulation engine; Rhicoceros3D with Grasshopper plugin and Ecotect, Radiance and EnergyPlus tools) that would enable a holistic approach to the spatial design of Near-Zero Energy buildings, so that their ecological benefits are an added value to the architectural design and a building’s visual, and material, impact on its surrounding space. The paper inquires how the integration of such technological infrastructure and performance-orientated interfaces changes yet again the structure and form of cities, and to what extent it safeguards social rights and enables equal access to common resources. Drawing from preliminary results and initial considerations of ongoing research that involve the construction of four innovative NZE settlements across Europe, in the context of the EU-funded ZERO-PLUS project, this paper discusses the integration of novel infrastructure in communal spaces of these settlements. In doing so, it contributes to the debate about smart communities and their role in the sustainable management of housing developments and settlements that are designed and developed with the concept of smart territories

    European Administration. Normative Fundaments and Systemic Models

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    Making use of the relevant literature in the area, this paper proposes a systemic approach to the European administration. The difficulty of the research design stems from the inconsistency of the regulations European treaties exhibit, as well as from the sectorial approaches, mostly of legal nature, on the conceptualization of the EU administration. To this we add the complexity of the analyzed process which, under the conditions set by the EU enlargement tends to overcome, both in sphere and content, many of the administrations of the federal states or international organizations. The systemic model we propose is a complex system, of a mixed architecture. It is there that the self-regulatory processes have a unique specificity and make use of both a legal foundation and of complementary processes such are those of Europeanization, convergence and administrative dynami
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