1,366 research outputs found

    Acetylene hydrogenation over structured Au-Pd catalysts

    Get PDF
    Acknowledgements We thank the University of Aberdeen for financial support and Dr K. McManus (University of Aberdeen) for performing preliminary experiments with these samples. Electron microscopy and EDS were performed by RTB at the Electron Microscopy Facility, University of St Andrews.Peer reviewedPostprin

    Nitrogen supply and cyanide concentration influence the enrichment of nitrogen from cyanide in wheat (Triticum aestivum L.) and sorghum (Sorghum bicolor L.)

    Get PDF
    Cyanide assimilation by the beta-cyanoalanine pathway produces asparagine, aspartate and ammonium, allowing cyanide to serve as alternate or supplemental source of nitrogen. Experiments with wheat and sorghum examined the enrichment of (15)N from cyanide as a function of external cyanide concentration in the presence or absence of nitrate and/or ammonium. Cyanogenic nitrogen became enriched in plant tissues following exposure to (15)N-cyanide concentrations from 5 to 200 microm, but when exposure occurred in the absence of nitrate and ammonium, (15)N enrichment increased significantly in sorghum shoots at solution cyanide concentrations of \u3e or =50 microm and in wheat roots at 200 microm cyanide. In an experiment with sorghum using (13)C(15)N, there was also a significant difference in the tissue (13)C:(15)N ratio, suggestive of differential metabolism and transport of carbon and nitrogen under nitrogen-free conditions. A reciprocal (15)N labelling study using KC(15)N and (15)NH(4)(+) and wheat demonstrated an interaction between cyanide and ammonium in roots in which increasing solution ammonium concentrations decreased the enrichment from 100 microm cyanide. In contrast, with increasing solution cyanide concentrations there was an increase in the enrichment from ammonium. The results suggest increased transport and assimilation of cyanide in response to decreased nitrogen supply and perhaps to ammonium supply

    Generational accounting in New Zealand: Is there generational balance

    Get PDF
    Abstract This paper uses a recently-developed technique, called generational accounting, to assess New Zealand's longterm fiscal position. Generational accounting has become a popular alternative to traditional deficit accounting, because it provides a more accurate picture of the intergenerational distribution of fiscal burdens and the associated macroeconomic effects, particularly in the presence of demographic transitions and large unfunded public transfer programs. Past studies have suggested the existence of significant generational imbalances in several countries. We find that behind New Zealand's projected budget surpluses, there is indeed a sound fiscal picture. Even under the base case scenario, which entails substantial short-run tax reductions, the burden on future generations (relative to income) is projected to fall slightly below that on current newborns. New Zealand appears to have avoided the large fiscal imbalances plaguing the United States and other OECD countries not by placing large tax burdens on young current generations, but by limiting the size of its commitments

    Diversity within the adenovirus fiber knob hypervariable loops influences primary receptor interactions

    Get PDF
    Adenovirus based vectors are of increasing importance for wide ranging therapeutic applications. As vaccines, vectors derived from human adenovirus species D serotypes 26 and 48 (HAdV-D26/48) are demonstrating promising efficacy as protective platforms against infectious diseases. Significant clinical progress has been made, yet definitive studies underpinning mechanisms of entry, infection, and receptor usage are currently lacking. Here, we perform structural and biological analysis of the receptor binding fiber-knob protein of HAdV-D26/48, reporting crystal structures, and modelling putative interactions with two previously suggested attachment receptors, CD46 and Coxsackie and Adenovirus Receptor (CAR). We provide evidence of a low affinity interaction with CAR, with modelling suggesting affinity is attenuated through extended, semi-flexible loop structures, providing steric hindrance. Conversely, in silico and in vitro experiments are unable to provide evidence of interaction between HAdV-D26/48 fiber-knob with CD46, or with Desmoglein 2. Our findings provide insight into the cell-virus interactions of HAdV-D26/48, with important implications for the design and engineering of optimised Ad-based therapeutics
    corecore