6,518 research outputs found

    The Spin--Symmetry of the Quark Model

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    Corrections to the exact heavy--quark symmetry results are expected to follow the 1/mQ1/m_{Q} mass effect of the heavy--quark. We show, by an explicit calculation, that there is something other than the mass effect that suppresses the breaking of the spin symmetry

    Project Cerberus: Flyby Mission to Pluto

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    The goal of the Cerberus Project was to design a feasible and cost-effective unmanned flyby mission to Pluto. The requirements in the request for proposal for an unmanned probe to Pluto are presented and were met. The design stresses proven technology that will avoid show stoppers which could halt mission progress. Cerberus also utilizes the latest advances in the spacecraft industry to meet the stringent demands of the mission. The topics covered include: (1) mission management, planning, and costing; (2) structures; (3) power and propulsion; (4) attitude, articulation, and control; (5) command, control, and communication; and (6) scientific instrumentation

    Advancing methodology for scoping reviews: recommendations arising from a scoping literature review (SLR) to inform transformation of Children and Adolescent Mental Health Services

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    Background There is consensus that health services commissioning and clinical practice should be driven by scientific evidence. However, workload pressures, accessibility of peer reviewed publications and skills to find, appraise, and synthesise relevant evidence are often cited as barriers to uptake of research evidence by practitioners and commissioners alike. In recent years a growing requirement for rapid evidence synthesis to inform commissioning decisions about healthcare service delivery and provision of care contributed to an increasing popularity of scoping literature reviews (SLRs). Yet, comprehensive guidelines for conducting and reporting SLRs are still relatively scarce. Methods The exemplar review used as a worked example aimed to provide a readily available, comprehensive, and user-friendly repository of research evidence for local commissioners to help them make evidence-informed decisions about redesigning East of England Children and Adolescent Mental Health Services. In conducting the review, we were broadly guided by Arksey and O’Malley’s framework, however some modifications were made at different stages to better reflect the largely pragmatic objective of this review. This paper compares the methodology used with existing methodological frameworks for scoping studies, to add to the existing knowledge base. Results We proposed the following advancements to the existing SLR frameworks: (i) Assemble a research team with complementary skills and expertise; (ii); Draw on expertise of external partners, particularly practitioners, decision-makers and commissioners who will be translating findings into practice; (iii) Pre-register the review protocol. Keep a detailed record of all steps and decisions and consider how they would impact on generalisability and utility of review findings; (iv) Use systematic procedures for literature searchers, selection of studies, data extraction and analysis; (v) If feasible, appraise the quality of included evidence; (vi) Be transparent about limitations of findings. Conclusions Despite some methodological limitations, scoping literature reviews are a useful method of rapidly synthesising a large body of evidence to inform commissioning and transformation of CAMHS. SLRs allow researchers to start with a broader questions, to explore the issue from different perspectives and perhaps find more comprehensive solutions that are not only effective, but also accounted for their feasibility and acceptability to key stakeholders

    Albumin-based hydrogels for regenerative engineering and cell transplantation.

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    Albumin, the most abundant plasma protein in mammals, is a versatile and easily obtainable biomaterial. It is pH and temperature responsive, dissolvable in high concentrations and gels readily in defined conditions. This versatility, together with its inexpensiveness and biocompatibility, makes albumin an attractive biomaterial for biomedical research and therapeutics. So far, clinical research in albumin has centered mainly on its use as a carrier molecule or nanoparticle to improve drug pharmacokinetics and delivery to target sites. In contrast, research in albumin-based hydrogels is less established albeit growing in interest over recent years. In this minireview, we report current literature and critically discuss the synthesis, mechanical properties, biological effects and uses, biodegradability and cost of albumin hydrogels as a xeno-free, customizable, and transplantable construct for tissue engineering and regenerative medicine.EPSRC Isaac Newton Trust Rosetrees Trus

    Delphi study to identify key features of community-based child and adolescent mental health services in the East of England.

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    OBJECTIVE: To identify priorities for the delivery of community-based Child and Adolescent Mental health Services (CAMHS). DESIGN: (1) Qualitative methods to gather public and professional opinions regarding the key principles and components of effective service delivery. (2) Two-round, two-panel adapted Delphi study. The Delphi method was adapted so professionals received additional feedback about the public panel scores. Descriptive statistics were computed. Items rated 8-10 on a scale of importance by ≥80% of both panels were identified as shared priorities. SETTING: Eastern region of England. PARTICIPANTS: (1) 53 members of the public; 95 professionals from the children's workforce. (2) Two panels. Public panel: round 1,n=23; round 2,n=16. Professional panel: round 1,n=44; round 2,n=33. RESULTS: 51 items met the criterion for between group consensus. Thematic grouping of these items revealed three key findings: the perceived importance of schools in mental health promotion and prevention of mental illness; an emphasis on how specialist mental health services are delivered rather than what is delivered (ie, specific treatments/programmes), and the need to monitor and evaluate service impact against shared outcomes that reflect well-being and function, in addition to the mere absence of mental health symptoms or disorders. CONCLUSIONS: Areas of consensus represent shared priorities for service provision in the East of England. These findings help to operationalise high level plans for service transformation in line with the goals and needs of those using and working in the local system and may be particularly useful for identifying gaps in ongoing transformation efforts. More broadly, the method used here offers a blueprint that could be replicated by other areas to support the ongoing transformation of CAMHS

    Work extremum principle: Structure and function of quantum heat engines

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    We consider a class of quantum heat engines consisting of two subsystems interacting via a unitary transformation and coupled to two separate baths at different temperatures Th>TcT_h > T_c. The purpose of the engine is to extract work due to the temperature difference. Its dynamics is not restricted to the near equilibrium regime. The engine structure is determined by maximizing the extracted work under various constraints. When this maximization is carried out at finite power, the engine dynamics is described by well-defined temperatures and satisfies the local version of the second law. In addition, its efficiency is bounded from below by the Curzon-Ahlborn value 1Tc/Th1-\sqrt{T_c/T_h} and from above by the Carnot value 1(Tc/Th)1-(T_c/T_h). The latter is reached|at finite power|for a macroscopic engine, while the former is achieved in the equilibrium limit ThTcT_h\to T_c. When the work is maximized at a zero power, even a small (few-level) engine extracts work right at the Carnot efficiency.Comment: 16 pages, 5 figure

    Calculating the transfer function of noise removal by principal component analysis and application to AzTEC observations

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    Instruments using arrays of many bolometers have become increasingly common in the past decade. The maps produced by such instruments typically include the filtering effects of the instrument as well as those from subsequent steps performed in the reduction of the data. Therefore interpretation of the maps is dependent upon accurately calculating the transfer function of the chosen reduction technique on the signal of interest. Many of these instruments use non-linear and iterative techniques to reduce their data because such methods can offer improved signal-to-noise over those that are purely linear, particularly for signals at scales comparable to that subtended by the array. We discuss a general approach for measuring the transfer function of principal component analysis (PCA) on point sources that are small compared to the spatial extent seen by any single bolometer within the array. The results are applied to previously released AzTEC catalogues of the COSMOS, Lockman Hole, Subaru XMM-Newton Deep Field, GOODS-North and GOODS-South fields. Source flux density and noise estimates increase by roughly +10 per cent for fields observed while AzTEC was installed at the Atacama Submillimeter Telescope Experiment and +15-25 per cent while AzTEC was installed at the James Clerk Maxwell Telescope. Detection significance is, on average, unaffected by the revised technique. The revised photometry technique will be used in subsequent AzTEC releases.Comment: 14 pages, 4 figure

    Foreign Direct Investments in Business Services: Transforming the Visegrád Four Region into a Knowledge-based Economy?

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    Foreign direct investments (FDIs) in the service sector are widely attributed an important role in bringing more skill-intensive activities into the Visegrad Four (V4). This region—comprising Poland, the Czech Republic, Hungary and Slovakia—relied heavily on FDIs in manufacturing, which was often found to generate activities with limited skill content. This contribution deconstructs the chaotic concept of “business services” by analysing the actual nature of service sector activities outsourced and offshored to the V4. Using the knowledge-based economy (KBE) as a benchmark, the paper assesses the potential of service sector outsourcing in contributing to regional competitiveness by increasing the innovative capacity. It also discusses the role of state policies towards service sector FDI (SFDI). The analysis combines data obtained from case studies undertaken in service sector outsourcing projects in V4 countries. Moreover, it draws on interviews with senior employees of investment promotion agencies and publicly available data and statistics on activities within the service sector in the region. It argues that the recent inward investments in business services in the V4 mainly utilize existing local human capital resources, and their contribution to the development of the KBE is limited to employment creation and demand for skilled labour

    Economic crisis and the construction of a neo-liberal regulatory regime in Korea

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    A consistent theme of the literature on the ontology of the 1997 South Korean crisis is the key role played by regulatory failures and the growing weakness of the state. This paper seeks to briefly highlight both the insights and the limitations of this approach to understanding the crisis. Having done so, we shall set out the argument that the crisis created an opportunity for reformist Korean élites to advance their longstanding, but previously frustrated, project to create a comprehensive unambiguously neo-liberal regulatory regime. This paper will also seek to highlight the implications of our reading of the development of the Korean political economy for broader debates on economic liberalisation, crisis and the future of the developmental state
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