8,444 research outputs found

    Sizing up nanoelectronics: gauging the potential for new productivity wave

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    The Federal Reserve Bank of Dallas, in cooperation with the Semiconductor Industry Association (SIA), hosted a conference on nanoelectronics and the economy in Austin on Dec. 3, 2010. Economists and scientists explored how information technology has affected U.S. productivity and output growth and prospects for the future.Technological innovations ; Productivity

    Semiprojectivity with and without a group action

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    The equivariant version of semiprojectivity was recently introduced by the first author. We study properties of this notion, in particular its relation to ordinary semiprojectivity of the crossed product and of the algebra itself. We show that equivariant semiprojectivity is preserved when the action is restricted to a cocompact subgroup. Thus, if a second countable compact group acts semiprojectively on a C*-algebra AA, then AA must be semiprojective. This fails for noncompact groups: we construct a semiprojective action of the integers on a nonsemiprojective C*-algebra. We also study equivariant projectivity and obtain analogous results, however with fewer restrictions on the subgroup. For example, if a discrete group acts projectively on a C*-algebra AA, then AA must be projective. This is in contrast to the semiprojective case. We show that the crossed product by a semiprojective action of a finite group on a unital C*-algebra is a semiprojective C*-algebra. We give examples to show that this does not generalize to all compact groups.Comment: 38 page

    Electromagnetic interactions for the two-body spectator equations

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    This paper presents a new non-associative algebra which is used to (i) show how the spectator (or Gross) two-body equations and electromagnetic currents can be formally derived from the Bethe-Salpeter equation and currents if both are treated to all orders, (ii) obtain explicit expressions for the Gross two-body electromagnetic currents valid to any order, and (iii) prove that the currents so derived are exactly gauge invariant when truncated consistently to any finite order. In addition to presenting these new results, this work complements and extends previous treatments based largely on the analysis of sums of Feynman diagrams.Comment: 44 pages, 14 figure

    An improved method for surface immobilisation of RNA: application to small Non-Coding RNA - mRNA pairing

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    Characterisation of RNA and its intermolecular interactions is increasing in importance as the inventory of known RNA functions continues to expand. RNA-RNA interactions are central to post-transcriptional gene regulation mechanisms in bacteria, and the interactions of bacterial small non-coding RNAs (sRNAs) with their mRNA targets are the subject of much current research. The technology of surface plasmon resonance (SPR) is an attractive approach to studying these interactions since it is highly sensitive, and allows interaction measurements to be recorded in real-time. Whilst a number of approaches exist to label RNAs for surface-immobilisation, the method documented here is simple, quick, efficient, and utilises the high-affinity streptavidin-biotin interaction. Specifically, we ligate a biotinylated nucleotide to the 3' end of RNA using T4 RNA ligase. Although this is a previously recognised approach, we have optimised the method by our discovery that the incorporation of four or more adenine nucleotides at the 3' end of the RNA (a poly-A-tail) is required in order to achieve high ligation efficiencies. We use this method within the context of investigating small non-coding RNA (sRNA)-mRNA interactions through the application of surface technologies, including quantitative SPR assays. We first focus on validating the method using the recently characterised Escherichia coli sRNA-mRNA pair, MicA-ompA, specifically demonstrating that the addition of the poly-A-tail to either RNA does not affect its subsequent binding interactions with partner molecules. We then apply this method to investigate the novel interactions of a Vibrio cholerae Qrr sRNA with partner mRNAs, hapR and vca0939; RNA-RNA pairings that are important in mediating pathogenic virulence. The calculated binding parameters allow insights to be drawn regarding sRNA-mRNA interaction mechanisms

    Integration in European Retail Banking : Evidence from savings and lending rates to non-financial corporations

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    The aim of this paper is to investigate the integration process in the European Union retail banking sector during the period 1995-2008, by analysing deposit and lending rates to nonfinancial corporations which represent one of the main constituents of retail banking. An important contribution of the paper is the application of the recently developed Phillips and Sul (2007a) panel convergence methodology which has not hitherto been employed in this area. This method analyses the degree as well as the speed of convergence, identifies the presence of club formation, and measures the behaviour of each country’s transition path relative to the panel average. The results obtained point to the presence of close convergence in all deposit rates and in the short-term lending rates to non-financial corporations. However, we also detect the presence of heterogeneity in the European retail banking sector with notably some diverse convergence patterns observed for the transition paths for the deposit and lending rates with longer maturities.Submitted Versio

    Promoting environmental management in very small businesses through “Green Angels” in a local collaborative partnership: a case study from Brighton, England

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    This paper describes the results of the East Brighton Employment and Environment Centre (EBEEC), a 15 month URBAN project, promoting environmental management to very small businesses in east Brighton, England. Some 31 volunteers, termed `Green Angels`, were trained in waste minimisation at the University of Brighton, and provided practical support to local firms through site reviews and research. The EBEEC project provided information and support to some 600 SMEs in east Brighton, via newsletters, email, telephone helpline, seminars and other projects. The Project was managed by a collaborative partnership formed from regional as well as local organisations. The involvement of a University to train potential `Green Angels`, so as to support SMEs in an area designated for economic regeneration, was an innovative and successful method of providing environmental management support to small firms. To stimulate the uptake of environmental management, case study material based on Best Practice was produced and disseminated to local companies via an Internet Site. A CD-Rom containing the Green Angel training package has been produced to help other projects like this. The outcomes from this Project will inform the regional and potentially the national approach to providing environmental business support and advice via local collaborative partnerships containing Universities
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