5,674 research outputs found

    Supporting security-oriented, collaborative nanoCMOS electronics research

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    Grid technologies support collaborative e-Research typified by multiple institutions and resources seamlessly shared to tackle common research problems. The rules for collaboration and resource sharing are commonly achieved through establishment and management of virtual organizations (VOs) where policies on access and usage of resources by collaborators are defined and enforced by sites involved in the collaboration. The expression and enforcement of these rules is made through access control systems where roles/privileges are defined and associated with individuals as digitally signed attribute certificates which collaborating sites then use to authorize access to resources. Key to this approach is that the roles are assigned to the right individuals in the VO; the attribute certificates are only presented to the appropriate resources in the VO; it is transparent to the end user researchers, and finally that it is manageable for resource providers and administrators in the collaboration. In this paper, we present a security model and implementation improving the overall usability and security of resources used in Grid-based e-Research collaborations through exploitation of the Internet2 Shibboleth technology. This is explored in the context of a major new security focused project at the National e-Science Centre (NeSC) at the University of Glasgow in the nanoCMOS electronics domain

    Less government intervention in biodiversity management: risks and opportunities

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    n a changing global environment, with increasing pressure on ecosystem goods and services, biodiversity conservation is likely to become increasingly important. However, with the current global financial crisis, governments are increasingly trying to stabilise economies through spending cuts aiming to reduce national deficits. Within such an economic climate, the devolution of governance through public participation is an intrinsically appealing concept. We outline a number of challenges that explain why increased participation in biodiversity management has been and may continue to be problematic. Using as a case study the local stakeholder-driven Moray Firth Seal Management Plan in Scotland, we identify four key conditions that were crucial to the successful participatory management of a biodiversity conflict: a local champion, the emergence of a crisis point, the involvement of decision-makers, and long-term financial and institutional support. Three of the four conditions point to the role of direct government involvement, highlighting the risk of devolving responsibility for biodiversity conflict management to local communities. We argue that without an informed debate, the move towards a more participatory approach could pose a danger to hard-won policy gains in relation to public participation, biodiversity conservation and conflict management

    Levels of genetic polymorphism: marker loci versus quantitative traits

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    Species are the units used to measure ecological diversity and alleles are the units of genetic diversity. Genetic variation within and among species has been documented most extensively using allozyme electrophoresis. This reveals wide differences in genetic variability within, and genetic distances among, species, demonstrating that species are not equivalent units of diversity. The extent to which the pattern observed for allozymes can be used to infer patterns of genetic variation in quantitative traits depends on the forces generating and maintaining variability. Allozyme variation is probably not strictly neutral but, nevertheless, heterozygosity is expected to be influenced by population size and genetic distance will be affected by time since divergence. The same is true for quantitative traits influenced by many genes and under weak stabilizing selection. However, the limited data available suggest that allozyme variability is a poor predictor of genetic variation in quantitative traits within populations. It is a better predictor of general phenotypic divergence and of postzygotic isolation between populations or species, but is only weakly correlated with prezygotic isolation. Studies of grasshopper and planthopper mating signal variation and assortative mating illustrate how these characters evolve independently of general genetic and morphological variation. The role of such traits in prezygotic isolation, and hence speciation, means that they will contribute significantly to the diversity of levels of genetic variation within and among species

    A novel polymorphism in the 5â€Č UTR of HvDEP1 is associated with grain length and 1000-grain weight in barley (Hordeum vulgare)

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    The gene HvDEP1, on barley (Hordeum vulgare L.) chromosome 5H, encodes a Îł-subunit of the heterotrimeric G-protein complex and was previously determined to be a candidate gene underlying a major quantitative trait locus for grain length. In the present study, we identified a 9 bp indel (insertion–deletion mutation) at position –84 bp from the start codon within a reported upstream open reading frame located in the 5â€Č UTR (untranslated region) and developed a diagnostic molecular marker. We also identified a 13 bp indel (–514 bp) in linkage disequilibrium that bridges an important regulatory motif. Using a doubled-haploid population and a barley diversity panel, we were able to show that the effects of these indels were environmentally stable and consistently delineated phenotypic groups based on grain length and 1000-grain weight. Genotypes represented by deletions at these two positions relative to the reference cv. Morex had consistently shorter grains, by 3.69–3.96%, and lower 1000-grain weight, by 2.38–4.21%, in a doubled-haploid population studied. Additionally, a diversity panel was tested but consistent differences were observed only for grain length, reinforcing literature indicating the importance of this gene for grain-length regulation. The frequency of the longer and heavier grained reference allele was higher in modern cultivars, suggesting that indirect selection for longer grain may have occurred through direct selection for grain yield via grain-weight improvement. These results indicate that grain length and 1000-grain weight in barley can be manipulated by targeting variation in gene promoters through marker-assisted selection

    An alternative search for the electron capture of Te-123

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    A search for the electron capture of Te-123 has been performed using CdZnTe detectors. After a measuring time of 195 h no signal could be found resulting in a lower half-life limt of T1/2>3.2⋅1016T_{1/2} > 3.2 \cdot 10^{16} yrs (95 % CL) for this process. This clearly discriminates between existing experimental results which differ by six orders of magnitude and our data are in strong favour of the result with longer half-lifes.Comment: 2 pages, 2 eps-figures, reanalysis of data set

    Integrating security solutions to support nanoCMOS electronics research

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    The UK Engineering and Physical Sciences Research Council (EPSRC) funded Meeting the Design Challenges of nanoCMOS Electronics (nanoCMOS) is developing a research infrastructure for collaborative electronics research across multiple institutions in the UK with especially strong industrial and commercial involvement. Unlike other domains, the electronics industry is driven by the necessity of protecting the intellectual property of the data, designs and software associated with next generation electronics devices and therefore requires fine-grained security. Similarly, the project also demands seamless access to large scale high performance compute resources for atomic scale device simulations and the capability to manage the hundreds of thousands of files and the metadata associated with these simulations. Within this context, the project has explored a wide range of authentication and authorization infrastructures facilitating compute resource access and providing fine-grained security over numerous distributed file stores and files. We conclude that no single security solution meets the needs of the project. This paper describes the experiences of applying X.509-based certificates and public key infrastructures, VOMS, PERMIS, Kerberos and the Internet2 Shibboleth technologies for nanoCMOS security. We outline how we are integrating these solutions to provide a complete end-end security framework meeting the demands of the nanoCMOS electronics domain

    Confinement of knotted polymers in a slit

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    We investigate the effect of knot type on the properties of a ring polymer confined to a slit. For relatively wide slits, the more complex the knot, the more the force exerted by the polymer on the walls is decreased compared to an unknotted polymer of the same length. For more narrow slits the opposite is true. The crossover between these two regimes is, to first order, at smaller slit width for more complex knots. However, knot topology can affect these trends in subtle ways. Besides the force exerted by the polymers, we also study other quantities such as the monomer-density distribution across the slit and the anisotropic radius of gyration.Comment: 9 pages, 6 figures, submitted for publicatio

    Composition of Ices in Low-Mass Extrasolar Planets

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    We study the formation conditions of icy planetesimals in protoplanetary disks in order to determine the composition of ices in small and cold extrasolar planets. Assuming that ices are formed from hydrates, clathrates, and pure condensates, we calculate their mass fractions with respect to the total quantity of ices included in planetesimals, for a grid of disk models. We find that the composition of ices weakly depends on the adopted disk thermodynamic conditions, and is rather influenced by the initial composition of the gas phase. The use of a plausible range of molecular abundance ratios and the variation of the relative elemental carbon over oxygen ratio in the gas phase of protoplanetary disks, allow us to apply our model to a wide range of planetary systems. Our results can thus be used to constrain the icy/volatile phase composition of cold planets evidenced by microlensing surveys, hypothetical ocean-planets and carbon planets, which could be detected by Corot or Kepler.Comment: Accepted for publication in The Astrophysical Journa

    M.I.T./Canadian Vestibular Experiments on the Spacelab-1 Mission. Part 1: Sensory Adaptation to Weightlessness and Readaptation to One-G: An Overview

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    Experiments on human spatial orientation were conducted on four crewmembers of Space Shuttle Spacelab Mission 1. The conceptual background of the project, the relationship among the experiments, and their relevance to a 'sensory reinterpretation hypothesis' are presented. Detailed experiment procedures and results are presented in the accompanying papers in this series. The overall findings are discussed as they pertain to the following aspects of hypothesized sensory reinterpretation in weightlessness: (1) utricular otolith afferent signals are reinterpreted as indicating head translation rather than tilt, (2) sensitivity of reflex responses to footward acceleration is reduced, and (3) increased weighting is given to visual and tactile cues in orientation perception and posture control. Results suggest increased weighting of visual cues and reduced weighting of graviceptor signals in weightlessness

    An observational study to examine how Cumulative Impact Zones influence alcohol availability from different types of licensed outlets in an inner London Borough

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    OBJECTIVES: Cumulative Impact Zones (CIZs) are a widely implemented local policy intended to restrict alcohol availability in areas proliferated with licensed outlets. Limited previous research has questioned their effectiveness and suggested they may play a more nuanced role in shaping local alcohol environments. This study evaluates the association between CIZ implementation and the number of licence applications made and the number issued, relative to a control region. DESIGN: A quantitative observational study. SETTING: The inner London Borough of Southwark, which currently enforces three CIZs. POPULATION: Licence applications received by Southwark Council’s Licensing Authority between 1 April 2006 and 31 March 2017 (N = 1254). INTERVENTIONS: CIZ implementation. PRIMARY OUTCOME MEASURES: Five outlet types were categorised and evaluated: Drinking Establishments, Eateries, Takeaways, Off Sales, and Other Outlets. Primary outcome measures were the number of applications received and the number of licences issued. These were analysed using Poisson regression of counts over time. RESULTS: Across all CIZs, implementation was associated with greater increases in the number of eateries in CIZ regions (IRR = 1.58, 95% CI: 1.02 – 2.52, P = 0.04) and number of takeaway venues (IRR = 3.89, 95% CI: 1.32 – 11.49, P = 0.01), relative to the control area. No discernible association was found for the remaining outlet types. Disaggregating by area indicated a 10-fold relative increase in the number of new eateries in Peckham CIZ (IRR = 10.38, 95% CI: 1.39 – 77.66, P = 0.02) and a four-fold relative increase in the number of newly licensed takeaways in Bankside CIZ (IRR = 4.38, 95% CI: 1.20 – 15.91, P = 0.03). CONCLUSIONS: Cumulative Impact Zones may be useful as policy levers to shape local alcohol environments to support the licensing goals of specific geographical areas and diversify the night-time economy
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