217 research outputs found
Charged Higgs bosons from the 3-3-1 models and the anomalies
Several anomalies in the semileptonic B-meson decays such as
have been reported by , Belle, and LHCb
collaborations recently. In this paper, we investigate the contributions of the
charged Higgs bosons from the 3-3-1 models to the
anomalies. We find that, in a wide range of parameter space, the 3-3-1 models
might give reasonable explanations to the anomalies and
other analogous anomalies of the B meson's semileptonic decays.Comment: Accpeted by Physical Review
A new mapping of the world for the new millennium
A new mapping of the world derived from connections between cities is presented as a complement to the traditional world map of countries. Under conditions of contemporary globalization world cities have emerged as global service centres. These have been created by the location strategies of leading corporate service firms (e.g. in accountancy) in setting up their global office networks. Data on the offices of 46 global service firms in 55 world cities are used to define service connections between cities. Connections are converted into measures of network proximity and a multidimensional scaling is applied to these ‘distances’ to create a ‘global service space’ of cities. This new mapping of the world shows a distinctive centric structure with the major world cities (e.g. London) at the core. Investigation of this general structure reveals more subtle patterns of interacting regional and hierarchical tendencies
Scaling the Peaks Research Protocol: understanding the barriers and drivers to providing and using dementia friendly community services in rural areas: a mixed methods study
Introduction: Scaling the Peaks is a cross-disciplinary research study which draws on medical ethnography, human geography and Geospatial Information Science (GIS) to address the issues surrounding the design and delivery of dementia friendly services in rural communities. The research question seeks to understand the barriers and drivers to the development of relevant, robust, reliable and accessible services which make a difference among older rural families affected by dementia.
Methods and analysis: This mixed methods study recruits both families affected by dementia who reside within the Peak District National Park, Derbyshire, and their service providers. The study explores the expectations and experiences of rural dementia by adopting a three part approach: (1) longitudinal ethnographic enquiry with up to 32 families affected by dementia (aged 70 years plus) who identify themselves as rural residents; (2) ethnographic semi-structured interviews and systematic observations of a range of statutory, third sector, private and local community initiative’s which seek to support older people living with dementia; (3) geospatial visual mapping of the qualitative and quantitative data. The ethnographic data will be used to explore the ideas of belonging in a community, perceptions of place and identity to determine the factors which influence everyday decisions about living well with dementia and, for the providers, working in a rural community. The geospatial component of the study seeks to incorporate quantitative and qualitative data, such as types, locations and allocation of services to produce an interactive web-based map for local communities to determine the future design and delivery of services when considering dementia friendly services.
Ethics and dissemination: The study is approved by the Leeds and Humberside Health Research Authority 16/YH/0163. The study is also approved by other participating organisations as required by their own governance procedures. The study includes people with dementia and as such adheres to the ethical considerations when including people with dementia. A publically available interactive visual map of the findings will be produced in relation to current services related to location and, by default, identify gaps in provision. Formal reports and dissemination activities will be undertaken in collaboration with the study advisory group members
Prevalence of true vein graft aneurysms: Implications for aneurysm pathogenesis
AbstractBackground: Circumstantial evidence suggests that arterial aneurysms have a different cause than atherosclerosis and may form part of a generalized dilating diathesis. The aim of this study was to compare the rates of spontaneous aneurysm formation in vein grafts performed either for popliteal aneurysms or for occlusive disease. The hypothesis was that if arterial aneurysms form a part of a systemic process, then the rates of vein graft aneurysms should be higher for patients with popliteal aneurysms than for patients with lower limb ischemia caused by atherosclerosis. Methods: Infrainguinal vein grafting procedures performed from 1990 to 1995 were entered into a prospective audit and graft surveillance program. Aneurysmal change was defined as a focal increase in the graft diameter of 1.5 cm or greater, excluding false aneurysms and dilatations after graft angioplasty. Results: During the study period, 221 grafting procedures were performed in 200 patients with occlusive disease and 24 grafting procedures were performed in 21 patients with popliteal aneurysms. Graft surveillance revealed spontaneous aneurysm formation in 10 of the 24 bypass grafts (42%) for popliteal aneurysms but in only 4 of the 221 grafting procedures (2%) that were performed for chronic lower limb ischemia. Conclusion:This study provides further evidence that aneurysmal disease is a systemic process, and this finding has clinical implications for the treatment of popliteal aneurysms. (J Vasc Surg 1999;29:403-8.
General approach to quantum mechanics as a statistical theory
Since the very early days of quantum theory there have been numerous attempts to interpret quantum mechanics as a statistical theory. This is equivalent to describing quantum states and ensembles together with their dynamics entirely in terms of phase-space distributions. Finite dimensional systems have historically been an issue. In recent works [Phys. Rev. Lett. 117, 180401 (2016) and Phys. Rev. A 96, 022117 (2017)] we presented a framework for representing any quantum state as a complete continuous Wigner function. Here we extend this work to its partner function—the Weyl function. In doing so we complete the phase-space formulation of quantum mechanics—extending work by Wigner, Weyl, Moyal, and others to any quantum system. This work is structured in three parts. First we provide a brief modernized discussion of the general framework of phase-space quantum mechanics. We extend previous work and show how this leads to a framework that can describe any system in phase space—putting it for the first time on a truly equal footing to Schrödinger's and Heisenberg's formulation of quantum mechanics. Importantly, we do this in a way that respects the unifying principles of “parity” and “displacement” in a natural broadening of previously developed phase-space concepts and methods. Secondly we consider how this framework is realized for different quantum systems; in particular we consider the proper construction of Weyl functions for some example finite dimensional systems. Finally we relate the Wigner and Weyl distributions to statistical properties of any quantum system or set of systems
A randomised controlled trial of a care home rehabilitation service to reduce long-term institutionalisation for elderly people
Objectives: to evaluate the effect of a care home rehabilitation service on institutionalisation, health outcomes and service use.
Design: randomised controlled trial, stratified by Barthel ADL index, social service sector and whether living alone. The intervention was a rehabilitation service based in Social Services old people's homes in Nottingham, UK. The control group received usual health and social care.
Participants: 165 elderly and disabled hospitalised patients who wished to go home but were at high risk of institutionalisation (81 intervention, 84 control).
Main outcome measures: institutionalisation rates, Barthel ADL index, Nottingham Extended ADL score, General Health Questionnaire (12 item version) at 3 and 12 months, Health and Social Service resource use.
Results: the number of participants institutionalised was similar at 3 months (relative risk 1.04, 95% confidence intervals 0.65–1.65) and 12 months (relative risk 1.23, 95% confidence intervals 0.75–2.02). Barthel ADL Index, Nottingham Extended ADL score and General Health Questionnaire scores were similar at 3 and 12 months. The intervention group spent significantly fewer days in hospital over 3 and 12 months (mean reduction 12.1 and 27.6 days respectively, P < 0.01), but spent a mean of 36 days in a care home rehabilitation service facility.
Conclusions: this service did not reduce institutionalisation, but diverted patients from the hospital to social services sector without major effects on activity levels or well-being
Problem detection in legislative oversight:An analysis of legislative committee agendas in the U.K. and U.S.
This paper outlines a dynamic problem-detection model of legislative oversight where legislative committees engage in information-gathering to identify emerging policy problems. It is argued that activities of legislative committees are responsive to indicators of problem status across a range of policy domains. This enables committees to react to problems before, or at least simultaneously to, citizens. Our analyses use a new dataset on the policy agenda of UK Parliamentary Select Committees in combination with directly comparable data on US Congressional hearings. Aggregate measures of problem status (e.g. GDP, crime rates) and public opinion on the �most important problem� facing the country are used as independent variables. The comparison between a well-established and developing committee system offers insights into common dynamics across institutional contexts. The findings show that committee agendas in both the UK and US are responsive to problem status for the majority of issues
Guidelines for the investigation of chronic diarrhoea in adults: British Society of Gastroenterology, 3rd edition
Chronic diarrhoea is a common problem, hence clear guidance on investigations is required. This is an updated guideline from 2003 for the investigations of chronic diarrhoea commissioned by the Clinical Services and Standards Committee of the British Society of Gastroenterology (BSG). This document has undergone significant revision in content through input by 13 members of the Guideline Development Group (GDG) representing various institutions. The GRADE system was used to appraise the quality of evidence and grading of recommendations
Molecular cytogenetic analysis of prostatic adenocarcinomas from screening studies : early cancers may contain aggressive genetic features
No objective parameters have been found so far that can predict the
biological behavior of early stages of prostatic cancer, which are
encountered frequently nowadays due to surveillance and screening
programs. We have applied comparative genomic hybridization to routinely
processed, paraffin-embedded radical prostatectomy specimens derived from
patients who participated in the European Randomized Study of Screening
for Prostate Cancer. We defined a panel consisting of 36 early cancer
specimens: 13 small (total tumor volume (Tv) < 0.5 ml) carcinomas and 23
intermediate (Tv between 0.5-1.0 ml) tumors. These samples were compared
with a set of 16 locally advanced, large (Tv > 2.0 ml) tumor samples, not
derived from the European Randomized Study of Screening for Prostate
Cancer. Chromosome arms that frequently (ie, > or = 15%) showed loss in
the small tumors included 13q (31%), 6q (23%), and Y (15%), whereas
frequent (ie, > or = 15%) gain was seen of 20q (15%). In the intermediate
cancers, loss was detected of 8p (35%), 16q (30%), 5q (26%), Y (22%), 6q,
and 18q (both 17%). No consistent gains were found i
Levels and equivalence in credit and qualifications frameworks: Contrasting the prescribed and enacted curriculum in school and college
Drawing on data from an empirical study of three matched subjects in upper secondary school and further education college in Scotland, this article explores some of the factors that result in differences emerging from the translation of the prescribed curriculum into the enacted curriculum. We argue that these differences raise important questions about equivalences which are being promoted through the development of credit and qualifications frameworks. The article suggests that the standardisation associated with the development of a rational credit and qualifications framework and an outcomes-based prescribed curriculum cannot be achieved precisely because of the multiplicity that emerges from the practices of translation
- …