22,218 research outputs found

    Conceptual design of an airborne laser Doppler velocimeter system for studying wind fields associated with severe local storms

    Get PDF
    An airborne laser Doppler velocimeter was evaluated for diagnostics of the wind field associated with an isolated severe thunderstorm. Two scanning configurations were identified, one a long-range (out to 10-20 km) roughly horizontal plane mode intended to allow probing of the velocity field around the storm at the higher altitudes (4-10 km). The other is a shorter range (out to 1-3 km) mode in which a vertical or horizontal plane is scanned for velocity (and possibly turbulence), and is intended for diagnostics of the lower altitude region below the storm and in the out-flow region. It was concluded that aircraft flight velocities are high enough and severe storm lifetimes are long enough that a single airborne Doppler system, operating at a range of less than about 20 km, can view the storm area from two or more different aspects before the storm characteristics change appreciably

    Novel six-coordinate Aryl- and Alkyltin complexes

    Get PDF
    Organo-tin compounds have wide applications as pesticides and as intermediates for organic synthesis.¹ They are invariably Sn(IV) derivatives and are generally four-coordinate.² The mixed organo/chioro compounds of the type RnSnCI4-n do however have the ability to expand their coordination numbers to five or six. This depends critically on the substituents - with four organic groups, R₄Sn, there is no tendency at all to coordinate extra ligands, while at the other extreme SnCl₄ readily forms six-coordinate [SnC1₄L₂] complexes since the electronegative halo groups increase the Lewis acidity of the tin centre

    Conceptualizing sport event legacy

    Get PDF
    Events legacies have become a common feature in the public policy rhetoric surrounding sport events of all sizes. Public policy planners and event organizers are increasingly promoting the legacies of sport events to justify significant investments required to host them. Within the context of special events, legacy is most often recognized as the long-term or permanent outcomes for a host city from staging an event. These outcomes include potential economic, tourism, social, physical, and/or environmental factors. However, the justification of legacies from events remains complicated due to inconsistent conceptualizations of legacy across academic and industry practice. While legacy is an increasing component of event bids as well as funding justifications and postevent reports, the concept itself has attracted limited critical analysis. This article puts forth a comprehensive review of literature that has sought to define legacy, from 1991-2008, drawing on event management, sport management, and urban planning contexts. An inductive interpretive analysis of definitions was undertaken, in which key considerations were identified and definitions assessed against these. The analysis revealed five key considerations of legacy in application to the sport event management context. In doing so, this article contributes to both theoretical debate and improved strategic practice surrounding the emergence of "legacy" as justification for staging sport events. © 2013 Cognizant Comm. Corp

    Intercommunity sport events: Vehicles and catalysts for social capital in divided societies

    Get PDF
    Sport events are believed to promote dialogue, integration, and peaceful understanding among disparate groups, even when other forms of negotiation have not been successful. However, the social outcomes from sport events are largely anecdotal and there is a need to empirically examine the active engagement of groups with "others" in participatory sport event projects. This article investigates the potential of an intercommunity sport event in contributing to intergroup development and social capital building in the ethnically divided Sri Lanka. It follows an interpretive mode of inquiry where findings are derived from the analysis of 35 in-depth interviews with Sinhalese, Tamil, Muslim, and international event stakeholders. By providing evidence of the varying sociocultural experiences at the event, this article discusses the event's impact on intergroup relations and its influence on the stock of social capital available to communities. Findings can assist governments, policy makers, and nongovernmental organizations (NGOs) in advancing policies and practical measures that build on events as vehicles and catalysts for enhanced intergroup relations and the creation of social capital. © 2011 Cognizant Comm. Corp

    Findings from a pilot randomised trial of an asthma internet self-management intervention (RAISIN)

    Get PDF
    <b>Objective </b>To evaluate the feasibility of a phase 3 randomised controlled trial (RCT) of a website (Living Well with Asthma) to support self-management.<p></p> <b>Design and setting</b> Phase 2, parallel group, RCT, participants recruited from 20 general practices across Glasgow, UK. Randomisation through automated voice response, after baseline data collection, to website access for minimum 12 weeks or usual care.<p></p> <b>Participants </b>Adults (age≥16 years) with physician diagnosed, symptomatic asthma (Asthma Control Questionnaire (ACQ) score ≥1). People with unstable asthma or other lung disease were excluded.<p></p> <b>Intervention</b> Living Well with Asthma’ is a desktop/ laptop compatible interactive website designed with input from asthma/ behaviour change specialists, and adults with asthma. It aims to support optimal medication management, promote use of action plans, encourage attendance at asthma reviews and increase physical activity.<p></p> <b>Outcome measures</b> Primary outcomes were recruitment/retention, website use, ACQ and mini- Asthma Quality of Life Questionnaire (AQLQ). Secondary outcomes included patient activation, prescribing, adherence, spirometry, lung inflammation and health service contacts after 12 weeks. Blinding postrandomisation was not possible.<p></p> <b>Results </b>Recruitment target met. 51 participants randomised (25 intervention group). Age range 16–78 years; 75% female; 28% from most deprived quintile. 45/51 (88%; 20 intervention group) followed up. 19 (76% of the intervention group) used the website, for a mean of 18 min (range 0–49). 17 went beyond the 2 ‘core’ modules. Median number of logins was 1 (IQR 1–2, range 0–7). No significant difference in the prespecified primary efficacy measures of ACQ scores (−0.36; 95% CI −0.96 to 0.23; p=0.225), and mini-AQLQ scores (0.38; −0.13 to 0.89; p=0.136). No adverse events.<p></p> <b>Conclusions</b> Recruitment and retention confirmed feasibility; trends to improved outcomes suggest use of Living Well with Asthma may improve self-management in adults with asthma and merits further development followed by investigation in a phase 3 trial

    Calculation of Elastic Green's Functions for Lattices with Cavities

    Full text link
    In this Brief Report, we present an algorithm for calculating the elastic Lattice Greens Function of a regular lattice, in which defects are created by removing lattice points. The method is computationally efficient, since the required matrix operations are on matrices that scale with the size of the defect subspace, and not with the size of the full lattice. This method allows the treatment of force fields with multi-atom interactions.Comment: 3 pages. RevTeX, using epsfig.sty. One figur

    Influence of FK 506 (tacrolimus) on circulating CD4 <sup>+</sup> t cells expressing cd25 and cd45ra antigens in 19 patients with chronic progressive multiple sclerosis participating in an open label drug safety trial

    Get PDF
    We have taken the opportunity of a clinical trial of the potential efficacy and safety of FK 506 (tacrolimus) in chronic progressive multiple sclerosis (MS) to examine the influence of this potent new immunosuppressant on circulating T-lymphocytes in an otherwise healthy non-transplant population. Peripheral blood levels of subsets of CD4+ T lymphocytes expressing the activation molecule interleukin-2 receptor (p55 α chain; CD25) or the CD45RA isoform were determined sequentially in 19 patients that were treated continuously with oral FK 506 (starting dose 0.15 mg/kg/day) for 12 months. No significant change in the proportion of circulating CD25 + CD4+ cells was observed over the study period in which the mean trough plasma FK 506 level rose from 0.3 ±0.2 to 0.5 ±0.4 ng/ml. There was also no significant effect of FK 506 on the percentage of CD45RA + CD4 + cells in the peripheral blood at 12 months compared with pretreatment values. Analysis of a subgroup of 7 patients, who showed a sustained reduction in CD25 + CD4+ cells and a reciprocal increase in CD45RA* CD4 * cells for at least 6 months after start of treatment, did not reveal any difference in disability at one year compared with the treatment group as a whole. The side effects of FK 506 were mild and the overall degree of disability estimated by the mean Kurtzke expanded disability status scale (EDSS) score or the ambulation index did not deteriorate significantly in the 19 patients studied over the 12 months of FK 506 administration. © 1994 Informa UK Ltd All rights reserved: reproduction in whole or part not permitted

    Quantum Analogue Computing

    Full text link
    We briefly review what a quantum computer is, what it promises to do for us, and why it is so hard to build one. Among the first applications anticipated to bear fruit is quantum simulation of quantum systems. While most quantum computation is an extension of classical digital computation, quantum simulation differs fundamentally in how the data is encoded in the quantum computer. To perform a quantum simulation, the Hilbert space of the system to be simulated is mapped directly onto the Hilbert space of the (logical) qubits in the quantum computer. This type of direct correspondence is how data is encoded in a classical analogue computer. There is no binary encoding, and increasing precision becomes exponentially costly: an extra bit of precision doubles the size of the computer. This has important consequences for both the precision and error correction requirements of quantum simulation, and significant open questions remain about its practicality. It also means that the quantum version of analogue computers, continuous variable quantum computers (CVQC) becomes an equally efficient architecture for quantum simulation. Lessons from past use of classical analogue computers can help us to build better quantum simulators in future.Comment: 10 pages, to appear in the Visions 2010 issue of Phil. Trans. Roy. Soc.

    Managed moves: schools collaborating for collective gain

    Get PDF
    Government guidance in the United Kingdom encourages groups of schools to take collective responsibility for supporting and making provision for excluded pupils and those at risk of exclusion. Managed-moves are one way that some schools and authorities are enacting such guidance. This paper presents the results of an evaluation of one such scheme. The scheme, involving seven neighbouring secondary schools, was nearing its first year of completion. The paper draws primarily on interview data with pupils, parents and school staff to describe a number of positive outcomes associated with the scheme and to explore how these were achieved. We found that while some of these could be attributed directly to the managed-move, others arose from the more inclusive ethos and practices of particular schools. The concepts of tailored support, care and commitment emerged as strong themes that underpinned the various practical ways in which some schools in the cluster were able to re-engage 'at-risk' pupils. As managed moves become more widely practiced it will be important to remember that it is how the move proceeds and develops rather than the move itself that will ultimately make the difference for troubled and troublesome pupils

    Two-dimensional soliton cellular automaton of deautonomized Toda-type

    Full text link
    A deautonomized version of the two-dimensional Toda lattice equation is presented. Its ultra-discrete analogue and soliton solutions are also discussed.Comment: 11 pages, LaTeX fil
    corecore