70 research outputs found

    Fermion Representation Of The Rolling Tachyon Boundary Conformal Field Theory

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    A free fermion representation of the rolling tachyon boundary conformal field theory is constructed. The representation is used to obtain an explicit, compact, exact expression for the boundary state. We use the boundary state to compute the disc and cylinder amplitudes for the half-S-brane.Comment: 27 page

    Closed String Field Theory with Dynamical D-brane

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    We consider a closed string field theory with an arbitrary matter current as a source of the closed string field. We find that the source must satisfy a constraint equation as a consequence of the BRST invariance of the theory. We see that it corresponds to the covariant conservation law for the matter current, and the equation of motion together with this constraint equation determines the classical behavior of both the closed string field and the matter. We then consider the boundary state (D-brane) as an example of a source. We see that the ordinary boundary state cannot be a source of the closed string field when the string coupling g turns on. By perturbative expansion, we derive a recursion relation which represents the bulk backreaction and the D-brane recoil. We also make a comment on the rolling tachyon boundary state.Comment: 30 pages, LaTeX2e, no figures. Typos are correcte

    Global and Local D-vortices

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    Codimension-two objects on a system of brane-antibrane are studied in the context of Born-Infeld type effective field theory with a complex tachyon and U(1)×\timesU(1) gauge fields. When the radial electric field is turned on in D2Dˉ{\bar {\rm D}}2, we find static regular global and local D-vortex solutions which could be candidates of straight cosmic D-strings in a superstring theory. A natural extension to DF-strings is briefly discussed.Comment: 24 pages, 10 eps figure

    Monitoring and evaluation of human resources for health: an international perspective

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    BACKGROUND: Despite the undoubted importance of human resources to the functions of health systems, there is little consistency between countries in how human resource strategies are monitored and evaluated. This paper presents an integrated approach for developing an evidence base on human resources for health (HRH) to support decision-making, drawing on a framework for health systems performance assessment. METHODS: Conceptual and methodological issues for selecting indicators for HRH monitoring and evaluation are discussed, and a range of primary and secondary data sources that might be used to generate indicators are reviewed. Descriptive analyses are conducted drawing primarily on one type of source, namely routinely reported data on the numbers of health personnel and medical schools as covered by national reporting systems and compiled by the World Health Organization. Regression techniques are used to triangulate a given HRH indicator calculated from different data sources across multiple countries. RESULTS: Major variations in the supply of health personnel and training opportunities are found to occur by region. However, certain discrepancies are also observed in measuring the same indicator from different sources, possibly related to the occupational classification or to the sources' representation. CONCLUSION: Evidence-based information is needed to better understand trends in HRH. Although a range of sources exist that can potentially be used for HRH assessment, the information that can be derived from many of these individual sources precludes refined analysis. A variety of data sources and analytical approaches, each with its own strengths and limitations, is required to reflect the complexity of HRH issues. In order to enhance cross-national comparability, data collection efforts should be processed through the use of internationally standardized classifications (in particular, for occupation, industry and education) at the greatest level of detail possible

    Comment letters to the National Commission on Commission on Fraudulent Financial Reporting, 1987 (Treadway Commission) Vol. 2

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    https://egrove.olemiss.edu/aicpa_sop/1662/thumbnail.jp

    Chapter 10 Scholarly Practice and Meaningful Research: Utilising Voice by Enabling Action … If it was Only that Simple!

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    The growing importance of ‘lived practices’ in entrepreneurship-related studies has sought to pose several questions and challenges for researchers/scholars in the field (Ruona & Gilley, 2009; Short, Keefer, & Stone, 2009). The issue of how current entrepreneurship research practices can become more applied in nature provides the basis for articulating more clearly what we mean by research impact and why it has become a central concern in the research field (Beyer & Trice, 1982; Huggins et al., 2008; Rynes, 2007; Starkey & Tempest, 2005). This debate has drawn specific attention to the need for applied research in entrepreneurial scholarship, which is more reflective of lived practice. The need to reach a balance between practitioners and academics’ expectations in terms of delivering research which is focussed towards achieving academic rigour and application to practice, which is both meaningful and relatable, is significant for both communities (Ram, Edwards, Jones, Kiselinchev, & Muchenje, 2014). This chapter seeks to assist and inspire both existing and future researchers in the field to make more informed choices and offer tangible evidence of good practice, serving as a guide to researchers wishing to develop engaged research.The authors hope that the nature of this chapter would seek to clarify the importance of engaged research in supporting how we understand and respond to the needs of entrepreneurial practice as a means of building trust and confidence in research reported. A key characteristic of the issue will be the different ‘framing’ of questions that can enhance practical knowledge

    Estimating the burden of antimicrobial resistance: a systematic literature review.

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    Background: Accurate estimates of the burden of antimicrobial resistance (AMR) are needed to establish the magnitude of this global threat in terms of both health and cost, and to paramaterise cost-effectiveness evaluations of interventions aiming to tackle the problem. This review aimed to establish the alternative methodologies used in estimating AMR burden in order to appraise the current evidence base. Methods: MEDLINE, EMBASE, Scopus, EconLit, PubMed and grey literature were searched. English language studies evaluating the impact of AMR (from any microbe) on patient, payer/provider and economic burden published between January 2013 and December 2015 were included. Independent screening of title/abstracts followed by full texts was performed using pre-specified criteria. A study quality score (from zero to one) was derived using Newcastle-Ottawa and Philips checklists. Extracted study data were used to compare study method and resulting burden estimate, according to perspective. Monetary costs were converted into 2013 USD. Results: Out of 5187 unique retrievals, 214 studies were included. One hundred eighty-seven studies estimated patient health, 75 studies estimated payer/provider and 11 studies estimated economic burden. 64% of included studies were single centre. The majority of studies estimating patient or provider/payer burden used regression techniques. 48% of studies estimating mortality burden found a significant impact from resistance, excess healthcare system costs ranged from non-significance to 1billionperyear,whilsteconomicburdenrangedfrom1 billion per year, whilst economic burden ranged from 21,832 per case to over $3 trillion in GDP loss. Median quality scores (interquartile range) for patient, payer/provider and economic burden studies were 0.67 (0.56-0.67), 0.56 (0.46-0.67) and 0.53 (0.44-0.60) respectively. Conclusions: This study highlights what methodological assumptions and biases can occur dependent on chosen outcome and perspective. Currently, there is considerable variability in burden estimates, which can lead in-turn to inaccurate intervention evaluations and poor policy/investment decisions. Future research should utilise the recommendations presented in this review. Trial registration: This systematic review is registered with PROSPERO (PROSPERO CRD42016037510)
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