1,640 research outputs found

    Apollo extension system lsv studies. mission command and control

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    Steering system and control circuit for Lunar Surface Vehicle /LSV/ - Apollo projec

    Apollo logistic support systems nolab studies- mission command and control interim report

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    Vehicle stability, steering, and control system characteristics for Apollo logistic support of lunar mobile laboratory /Molab

    Dryland Clovers: A Phytochemical Resource

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    Recent developments in the utilisation of phytoestrogens of red clover (Wuttke et al., 2002) have encouraged us to investigate a wider range of Trifolium species for metabolites which could provide new product opportunities. The phytochemistry of the agronomically-important Trifolium species white (Trifolium repens) and red (T. pratense) clovers has been investigated in some detail (Foo et al., 2000; Sivakumaran et al., 2004). However numerous other clover species have been neglected in agriculture due to agronomic issues or the fact they are annuals and require more intensive management. While some of these clover species have been studied for their genetic diversity (Marshall et al., 2002), investigations of the chemical composition of these specific species has not been reported

    Optimizing end-labeled free-solution electrophoresis by increasing the hydrodynamic friction of the drag-tag

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    We study the electrophoretic separation of polyelectrolytes of varying lengths by means of end-labeled free-solution electrophoresis (ELFSE). A coarse-grained molecular dynamics simulation model, using full electrostatic interactions and a mesoscopic Lattice Boltzmann fluid to account for hydrodynamic interactions, is used to characterize the drag coefficients of different label types: linear and branched polymeric labels, as well as transiently bound micelles. It is specifically shown that the label's drag coefficient is determined by its hydrodynamic size, and that the drag per label monomer is largest for linear labels. However, the addition of side chains to a linear label offers the possibility to increase the hydrodynamic size, and therefore the label efficiency, without having to increase the linear length of the label, thereby simplifying synthesis. The third class of labels investigated, transiently bound micelles, seems very promising for the usage in ELFSE, as they provide a significant higher hydrodynamic drag than the other label types. The results are compared to theoretical predictions, and we investigate how the efficiency of the ELFSE method can be improved by using smartly designed drag-tags.Comment: 32 pages, 11 figures, submitted to Macromolecule

    Nighttime removal of NOx in the summer marine boundary layer

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    The nitrate radical, NO3, and dinitrogen pentoxide, N2O5, are two important components of nitrogen oxides that occur predominantly at night in the lower troposphere. Because a large fraction of NO2 reacts to form NO3 and N2O5 during the course of a night, their fate is an important determining factor to the overall fate of NOx (=NO and NO2). As a comprehensive test of nocturnal nitrogen oxide chemistry, concentrations of O3, NO, NO2, NO3, N2O5, HNO3 and a host of other relevant compounds, aerosol abundance and composition, and meteorological conditions were measured in the marine boundary layer from the NOAA research vessel Ronald H. Brown off the East Coast of the United States as part of the New England Air Quality Study (NEAQS) during the summer of 2002. The results confirm the prominent role of NO3 and N2O5 in converting NOx to HNO3 at night with an efficiency on par with daytime photochemical conversion. The findings demonstrate the large role of nighttime chemistry in determining the NOx budget and consequent production of ozone. INDEX TERMS: 0322 Atmospheric Composition and Structure: Constituent sources and sinks; 0345 Atmospheric Composition and Structure: Pollution—urban and regional (0305); 0365 Atmospheric Composition and Structure: Troposphere—composition and chemistry. Citation: Brown, S. S., et al. (2004), Nighttime removal of NOx in the summer marine boundary layer, Geophys. Res. Lett., 31, L07108, doi:10.1029/2004GL01941

    Bringing bioinformatics to schools with the 4273pi project

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    The work was supported by the Science and Technology Facilities Council (STFC) under Grants STFC ST/R000328/1 (including salary to S.A.B., D.B., H.P., T.R.M. and non-salary costs) and STFC ST/T000872/1 (including salary to S.A.B., D.B., K.C., T.R.M. and non-salary costs), the Darwin Trust of Edinburgh (https://darwintrust.bio.ed.ac.uk; including salary to S.A.B. and H.P. and non-salary costs), the Wellcome Trust-University of Edinburgh Institutional Strategic Support Fund under Wellcome Trust Grant number 204804/Z/16/Z (salary to H.P.), a Public Engagement with Genetics Tier 2 Grant from the Genetics Society (https://genetics.org.uk; non-salary costs), the Natural Environment Research Council (NERC) under Grant NE/P000592/1 (including salary to N.C. and M.G.R. and non-salary costs), the Biotechnology and Biological Sciences Research Council (BBSRC) under Grant BB/S018506/1 (including salary to F.A. and non-salary costs), the School of Biological Sciences at the University of Edinburgh (https://www.ed.ac.uk/biology; including salary to S.A.B. and H.P. and non-salary costs) and its Institute of Evolutionary Biology (https://www.ed.ac.uk/biology/evolutionary-biology; non-salary costs), the Access for Rural Communities project (ARC) at University of St Andrews (https://www.st-andrews.ac.uk/study/access/projects/arc; non-salary costs) and the Engineering and Physical Sciences Research Council (EPSRC) under Grant EP/V52038X/1 (including salary to S.A.B. and non-salary costs). E.W.J.W. is supported by a Sir Henry Dale Fellowship jointly funded by the Wellcome Trust and the Royal Society [208779/Z/17/Z] (including salary to E.W.J.W.).Over the last few decades, the nature of life sciences research has changed enormously, generating a need for a workforce with a variety of computational skills such as those required to store, manage, and analyse the large biological datasets produced by next-generation sequencing. Those with such expertise are increasingly in demand for employment in both research and industry. Despite this, bioinformatics education has failed to keep pace with advances in research. At secondary school level, computing is often taught in isolation from other sciences, and its importance in biological research is not fully realised, leaving pupils unprepared for the computational component of Higher Education and, subsequently, research in the life sciences. The 4273pi Bioinformatics at School project (https://4273pi.org) aims to address this issue by designing and delivering curriculum-linked, hands-on bioinformatics workshops for secondary school biology pupils, with an emphasis on equitable access. So far, we have reached over 180 schools across Scotland through visits or teacher events, and our open education resources are used internationally. Here, we describe our project, our aims and motivations, and the practical lessons we have learned from implementing a successful bioinformatics education project over the last 5 years.Publisher PDFPeer reviewe

    Teachers' perceptions of the value of research-based school lectures

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    A major challenge facing secondary schools is to encourage students to take computing courses. One approach is to invite external speakers from universities or industry to give lectures. The cs4fn project, a large UK-based initiative to enthuse students about computer science, includes this approach. Speakers from Queen Mary, University of London, visit schools to talk to students about computer science research. Our interactive talks tell engaging research-based stories on topics such as artificial intelligence and human-computer interaction as well as using magic tricks to illustrate computing principles. We asked teachers to complete post-talk surveys online; in particular we were interested in whether they believed students’ perceptions of the subject had changed. They reported that their students’ views of computer science were improved, and that they felt students were more likely to take classes in computing in the future as a result of the talk

    Taxing the Informal Economy: The Current State of Knowledge and Agendas for Future Research

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    This paper reviews the literature on taxation of the informal economy, taking stock of key debates and drawing attention to recent innovations. Conventionally, the debate on whether to tax has frequently focused on the limited revenue potential, high cost of collection, and potentially adverse impact on small firms. Recent arguments have increasingly emphasised the more indirect benefits of informal taxation in relation to economic growth, broader tax compliance, and governance. More research is needed, we argue, into the relevant costs and benefits for all, including quasi-voluntary compliance, political and administrative incentives for reform, and citizen-state bargaining over taxation
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