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The kinetics of the liquid-phase hydrogenation of citral (3,7-dimethyl-2,6-octadienal) on Au/TiO2 and Pt-Sn/TiO2 thin films was studied in the temperature range 313-353 K and citral concentrations of 0.25-10.0 mol m(-3). The thin films were deposited onto the inner walls of silica capillaries with internal diameter of 250 mu m. First-order dependence on hydrogen pressure and near zero order dependence on citral concentration were observed for the initial rate of citral hydrogenation over the Pt-Sn/TiO2 and Au/TiO2 thin films. The Au/TiO2 catalyst prevents citronellal formation. The highest yield of unsaturated alcohols was obtained on the Pt-Sn/TiO2 film at a reaction temperature of 343 K, liquid residence time of 30 min and a citral conversion of 99%. (C) 2011 Elsevier B.V. All rights reserved.

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We have modeled the gas phase chemistry of warm molecular material around protostars that is seeded with evaporating grain mantles. We show that the release of simple molecules into the gas drives ion-molecule and neutral chemistries which can account for many of the complex 0-bearing and N-bearing molecules observed in hot cores. Initial grain mantle components and secondary product molecules are identified, and the observational consequences are discussed.

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Q fever is caused by Coxiella burnetii and often has an insidious clinical presentation. We describe a rare case of Q fever infection of an aortic graft presenting with pyrexia and constant severe midlumbar pain due to erosion of multiple vertebral bodies. After successful treatment with graft resection and extra-anatomic vascular reconstruction, the patient continues on lifelong antibiotic therapy. We also present regional Q fever epidemiologic data together with a review of all previously documented cases of Q fever infections of vascular prostheses.

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This paper describes a collaborative practice, between an architect (the author) and a textile designer; its outcomes and the critical theoretical and feminist contexts from which the practice evolved and to which it still responds. The practice advocates the interweaving of more than the yarns, material and cultures on which it is physically based, but also the intertwining of theory and technology as a means to advance architectural practice. This is done in response to Ahrentzen’s charge to feminist scholars and practitioners to ‘embrace not only the abstract conceptual nature of much postmodernist theorizing but also that derived from the serious “hanging out”, looking at, listening to, scrutinising and theorizing lived experiences of the everyday’, in this instance the everyday practice of combining concrete and textiles.

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The aim of this paper is to analyse credit union industries within a development framework. Explicit consideration is given to credit union industries in four countries – Great Britain, Ireland, New Zealand and the United States. It is argued that in terms of a developmental typology the credit union industry in Great Britain is at a nascent stage of development, the industries in Ireland and New Zealand are at a transition stage while the US credit union industry is mature in nature. In progression between stages the analysis considers the influence of factors such as situational leadership, the complexion of trade associations, professionalisation, regulatory and legislative initiatives and technology. The analysis concluded that while there was a substantial commonality of experience, there were also significant differences in the impact of these factors. This consequently encouraged the recognition of the existence of ‘a variety of the species’ in respect of credit union development.

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1. We examined the empirical relationship between predator-prey body size ratio and interaction strength in the Ythan Estuary food web.

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Speeding up sequential programs on multicores is a challenging problem that is in urgent need of a solution. Automatic parallelization of irregular pointer-intensive codes, exempli?ed by the SPECint codes, is a very hard problem. This paper shows that, with a helping hand, such auto-parallelization is possible and fruitful. This paper makes the following contributions: (i) A compiler framework for extracting pipeline-like parallelism from outer program loops is presented. (ii) Using a light-weight programming model based on annotations, the programmer helps the compiler to ?nd thread-level parallelism. Each of the annotations speci?es only a small piece of semantic information that compiler analysis misses, e.g. stating that a variable is dead at a certain program point. The annotations are designed such that correctness is easily veri?ed. Furthermore, we present a tool for suggesting annotations to the programmer. (iii) The methodology is applied to autoparallelize several SPECint benchmarks. For the benchmark with most parallelism (hmmer), we obtain a scalable 7-fold speedup on an AMD quad-core dual processor. The annotations constitute a parallel programming model that relies extensively on a sequential program representation. Hereby, the complexity of debugging is not increased and it does not obscure the source code. These properties could prove valuable to increase the ef?ciency of parallel programming.