32,045 research outputs found

    Dread and latency impacts on a VSL for cancer risk reduction

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    We propose a structural relationship between the value of preventing a statistical cancer fatality and the value of statistical life (VSL) for risks of an instantaneous road accident fatality. This relationship incorporates a context effect reflecting both the illness or ‘morbidity’ associated with cancer fatality and the ‘dread’ or horror associated with the prospect of eventual death from cancer, as well as a latency effect that captures the discounting likely to arise because the onset of the symptoms of cancer typically occurs after some delay. We use a Risk-Risk trade-off study to validate this model by directly estimating the influence of context and latency effects upon the relative size of the VSL for cancer and for road accidents, confirming that both effects are significant and estimating their size using regression analysis. We show that morbidity accounts for the majority of the context premium. We use the elicited coefficients to reconstruct VSL estimates for a range of cancers characterised by their latency and morbidity periods

    The structure of the Au(111)/methylthiolate interface : new insights from near-edge X-ray absorption spectroscopy and X-ray standing waves

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    The local structure of the Au(111)([square root of]3×[square root of]3)R30°-methylthiolate surface phase has been investigated by S K-edge near-edge s-ray absorption fine structure (NEXAFS) both experimentally and theoretically and by experimental normal-incidence x-ray standing waves (NIXSW) at both the C and S atomic sites. NEXAFS shows not only excitation into the intramolecular sigma* S–C resonance but also into a sigma* S–Au orbital perpendicular to the surface, clearly identifying the local S headgroup site as atop a Au atom. Simulations show that it is not possible, however, to distinguish between the two possible adatom reconstruction models; a single thiolate species atop a hollow-site Au adatom or a dithiolate moiety comprising two thiolate species bonded to a bridge-bonded Au adatom. Within this dithiolate moiety a second sigma* S–Au orbital that lies near parallel to the surface has a higher energy that overlaps that of the sigma* S–C resonance. The new NIXSW data show the S–C bond to be tilted by 61° relative to the surface normal, with a preferred azimuthal orientation in , corresponding to the intermolecular nearest-neighbor directions. This azimuthal orientation is consistent with the thiolate being atop a hollow-site Au adatom, but not consistent with the originally proposed Au-adatom-dithiolate moiety. However, internal conformational changes within this species could, perhaps, render this model also consistent with the experimental data

    Examining the Antecedent Role of Movement Proficiency in Child Development: Study Protocol

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    Background: Decades of research, largely from associational studies, show that the relationships of movement proficiency with the cognitive and social aspects of development are particularly strong in early childhood. Children who move proficiently tend to have better cognitive skills and social behaviors. However, the mechanisms that underpin these relationships remain unclear and research that explores causation is necessary. This study will explore the antecedent role of movement proficiency in the cognitive and social domains of child development, by examining whether a targeted movement skills training program facilitates improvements in cognitive and social skills. Methods: A group-randomized controlled trial will be conducted, implementing a fundamental movement skills training program in Hong Kong kindergartens. Participants will consist of children aged 3–5 years (N = 158) who will be randomly allocated by class to either a training or active control condition. The training program (10 weeks × 2 bouts) will be informed by an error-reduced approach to skills learning, which will involve careful design and manipulation of equipment and training environment to minimize practice errors. The active control condition will consist of typical movement activities implemented in the kindergartens in the context of the local curriculum guide. Outcomes will be measured using standardized tests of gross motor skills proficiency, executive functioning, and social skills. Measurements will occur at baseline, mid-training, post-training, and follow-up. Latent variable longitudinal modeling will be used to analyze changes in the outcomes, with covariates that include sex, body composition, fine motor skills, and physical activity. Expected Results: The findings will subsequently be reported consistent with the Consolidated Standards of Reporting Trials (CONSORT) statement. Contributions to knowledge and understanding of child development are expected, through evidence of causal mechanisms surrounding the relationship of motor with cognitive and social development. The findings will also inform policy and practice related to early childhood development and education

    Quantum Holonomy in Three-dimensional General Covariant Field Theory and Link Invariant

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    We consider quantum holonomy of some three-dimensional general covariant non-Abelian field theory in Landau gauge and confirm a previous result partially proven. We show that quantum holonomy retains metric independence after explicit gauge fixing and hence possesses the topological property of a link invariant. We examine the generalized quantum holonomy defined on a multi-component link and discuss its relation to a polynomial for the link.Comment: RevTex, 12 pages. The metric independence of path integral measure is justified and the case of multi-component link is discussed in detail. To be published in Physical Review

    A New Approach to Environmental Valuation for New Zealand

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    New Zealand’s Resource Management Act is frequently criticised for the costs and delays it imposes on activities, but less attention is given to the consistency of values it applies to environmental effects through its decisions. The wide variety of parties who exercise decision roles under the act lack guidance on the economic value of the environment, and non-market valuation studies are too costly to be widely used and too few and varied to infer reliable generic values. Drawing on experience in estimating the public value of safety improvements, this article proposes an alternative approach that measures people’s aversion to the risk of environmental impacts of different scales and severity which could yield values sufficiently generic to be widely used, and outlines its uses both within and beyond the RMA applications

    Cholesterol dependence of HTLV-I infection

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    Cholesterol-rich plasma membrane microdomains are important for entry of many viruses, including retro-viruses. Depletion of cholesterol with 2-hydroxypropyl-β-cyclodextrin inhibits entry of human T cell leukemia virus type I (HTLV-1) and HTLV-I envelope pseudotyped lentivirus particles. Using a soluble fusion protein of the HTLV-I surface envelope protein with the immunoglobulin Fc domain, the HTLV-I receptor was found to colocalize with a raft-associated marker and to cluster in specific plasma membrane microdomains. Depletion of cholesterol did not alter receptor binding activity, suggesting a requirement for cholesterol in a postbinding virus entry step

    High-Speed Imaging Optical Pyrometry for Study of Boron Nitride Nanotube Generation

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    A high-speed imaging optical pyrometry system is designed for making in-situ measurements of boron temperature during the boron nitride nanotube synthesis process. Spectrometer measurements show molten boron emission to be essentially graybody in nature, lacking spectral emission fine structure over the visible range of the electromagnetic spectrum. Camera calibration experiments are performed and compared with theoretical calculations to quantitatively establish the relationship between observed signal intensity and temperature. The one-color pyrometry technique described herein involves measuring temperature based upon the absolute signal intensity observed through a narrowband spectral filter, while the two-color technique uses the ratio of the signals through two spectrally separated filters. The present study calibrated both the one- and two-color techniques at temperatures between 1,173 K and 1,591 K using a pco.dimax HD CMOS-based camera along with three such filters having transmission peaks near 550 nm, 632.8 nm, and 800 nm

    Multi-point Adjoint-Based Design of Tilt-Rotors in a Noninertial Reference Frame

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    Optimization of tilt-rotor systems requires the consideration of performance at multiple design points. In the current study, an adjoint-based optimization of a tilt-rotor blade is considered. The optimization seeks to simultaneously maximize the rotorcraft figure of merit in hover and the propulsive efficiency in airplane-mode for a tilt-rotor system. The design is subject to minimum thrust constraints imposed at each design point. The rotor flowfields at each design point are cast as steady-state problems in a noninertial reference frame. Geometric design variables used in the study to control blade shape include: thickness, camber, twist, and taper represented by as many as 123 separate design variables. Performance weighting of each operational mode is considered in the formulation of the composite objective function, and a build up of increasing geometric degrees of freedom is used to isolate the impact of selected design variables. In all cases considered, the resulting designs successfully increase both the hover figure of merit and the airplane-mode propulsive efficiency for a rotor designed with classical techniques
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