557 research outputs found

    Differences in views of experts about their role in particulate matter policy advice: Empirical evidence from an international expert consultation

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    There is ample scientific evidence of adverse health effects of air pollution at exposure levels that are common among the general population. Some points of uncertainty remain, however. Several theories exist regarding the various roles that experts may play when they offer policy advice on uncertain issues such as particulate matter (PM). Roles may vary according to e.g. the views of the expert on the science-policy interface or the extent to which she/he involves stakeholders. Empirical underpinning of these theories, however, does not exist. We therefore conducted a consultation with experts on the following research question: What are PM experts’ views on their roles when providing policy advice? Q methodology was used to empirically test theoretical notions concerning the existence of differences in views on expert roles. Experts were selected based on a structured nominee process. In total, 31 international PM experts participated. Responses were examined via Principal Component Analysis, and for the open-ended questions, we used Atlas.ti software. Four different expert roles were identified among the participating experts. Main differences were found with respect to views on the need for precautionary measures and on the experts positioning within the science-policy interface. There was consensus on certain issues such as the need for transparency, general disagreement with current policies and general agreement on key scientific issues. This empirical study shows that while most PM experts consider their views on the risks of PM to be in line with those of their colleagues, four distinct expert roles were observed. This provides support for thus far largely theoretical debates on the existence of different roles of experts when they provide policy advice

    Экзистенциальный базис сущностных сред

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    Создается экзистенциальная платформа дескриптивных сред. На ее основе строятся модели информатико-технологических систем. Проводится прагматико-обусловленная типизация универсума компаундов. Раскрывается компа- ундная природа средств квантификации и суперпозиции функций.Створюється екзистенційна платформа дескриптивних середовищ. На її основі будуються логіко-математичні моделі інформатико-технологічних систем. Проводиться прагматико обумовлена типізація універсуму компаундів. Розглядається компаундна природа засобів квантифікації та суперпозиції функційAn existential platform of descriptive environments has been created, on the basis of which logic-mathematical models of informative technological systems are built. A pragmatically conditioned typification of the universal set of compounds is performed. The compound nature of the means of quantification and superposition of function is discussed

    Neurobehavioral effects of transportation noise in primary schoolchildren: a cross-sectional study.

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    This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.BACKGROUND: Due to shortcomings in the design, no source-specific exposure-effect relations are as yet available describing the effects of noise on children's cognitive performance. This paper reports on a study investigating the effects of aircraft and road traffic noise exposure on the cognitive performance of primary schoolchildren in both the home and the school setting. METHODS: Participants were 553 children (age 9-11 years) attending 24 primary schools around Schiphol Amsterdam Airport. Cognitive performance was measured by the Neurobehavioral Evaluation System (NES), and a set of paper-and-pencil tests. Multilevel regression analyses were applied to estimate the association between noise exposure and cognitive performance, accounting for demographic and school related confounders. RESULTS: Effects of school noise exposure were observed in the more difficult parts of the Switching Attention Test (SAT): children attending schools with higher road or aircraft noise levels made significantly more errors. The correlational pattern and factor structure of the data indicate that the coherence between the neurobehavioral tests and paper-and-pencil tests is high. CONCLUSIONS: Based on this study and previous scientific literature it can be concluded that performance on simple tasks is less susceptible to the effects of noise than performance on more complex tasks.Funding was provided by the European Community (QLRT-2000-00197), the Department of Environment, Food and Rural Affairs in the UK, the Dutch Ministry of Spatial Planning, Housing and the Environment, the Dutch Ministry of Public Health, Welfare and Sports, and the Dutch Ministry of Transport, Public Works and Water Management

    Fast Fourier Optimization: Sparsity Matters

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    Many interesting and fundamentally practical optimization problems, ranging from optics, to signal processing, to radar and acoustics, involve constraints on the Fourier transform of a function. It is well-known that the {\em fast Fourier transform} (fft) is a recursive algorithm that can dramatically improve the efficiency for computing the discrete Fourier transform. However, because it is recursive, it is difficult to embed into a linear optimization problem. In this paper, we explain the main idea behind the fast Fourier transform and show how to adapt it in such a manner as to make it encodable as constraints in an optimization problem. We demonstrate a real-world problem from the field of high-contrast imaging. On this problem, dramatic improvements are translated to an ability to solve problems with a much finer grid of discretized points. As we shall show, in general, the "fast Fourier" version of the optimization constraints produces a larger but sparser constraint matrix and therefore one can think of the fast Fourier transform as a method of sparsifying the constraints in an optimization problem, which is usually a good thing.Comment: 16 pages, 8 figure

    On the Dominance of Trivial Knots among SAPs on a Cubic Lattice

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    The knotting probability is defined by the probability with which an NN-step self-avoiding polygon (SAP) with a fixed type of knot appears in the configuration space. We evaluate these probabilities for some knot types on a simple cubic lattice. For the trivial knot, we find that the knotting probability decays much slower for the SAP on the cubic lattice than for continuum models of the SAP as a function of NN. In particular the characteristic length of the trivial knot that corresponds to a `half-life' of the knotting probability is estimated to be 2.5×1052.5 \times 10^5 on the cubic lattice.Comment: LaTeX2e, 21 pages, 8 figur

    Особливості перебігу та корекції артеріальної гіпертензії у хворих з супутньою вегетативною дисфункцією на курорті Трускавець

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    Частота синдрома вегетативной дисфункции у больных гипертонией составляет 60-70%, что существенно усложняет течение заболевания и ухудшает качество жизни пациентов. Больным гипертонией с признаками симпатикотонии целесообразно назначать бета-блокатор Корвазан и биологически активную воду Нафтуся, так так они существенно снижают частоту вегето-сосудистых кризов. Билогически активная вода Нафтуся содействует уменьшению количеству автономных нарушений и более быстрому достижению целевых уровней артериального давления

    Роль військових у формуванні євроатлантичної політики України

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    7 квітня 2009 року на базі Чернігівського центру євроатлантичної інтеграції відбувся інтерактивний семінар на тему: «Роль військових у формуванні євроатлантичної політики України». Захід провів Інститут трансформації суспільства (Київ, директор - Олег Соскін) спільно із Чернігівським державним педагогічним університетом їм. Т.Г. Шевченка за підтримки Посольства Словацької Республіки в Україні.

    Effective interaction between helical bio-molecules

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    The effective interaction between two parallel strands of helical bio-molecules, such as deoxyribose nucleic acids (DNA), is calculated using computer simulations of the "primitive" model of electrolytes. In particular we study a simple model for B-DNA incorporating explicitly its charge pattern as a double-helix structure. The effective force and the effective torque exerted onto the molecules depend on the central distance and on the relative orientation. The contributions of nonlinear screening by monovalent counterions to these forces and torques are analyzed and calculated for different salt concentrations. As a result, we find that the sign of the force depends sensitively on the relative orientation. For intermolecular distances smaller than 6A˚6\AA it can be both attractive and repulsive. Furthermore we report a nonmonotonic behaviour of the effective force for increasing salt concentration. Both features cannot be described within linear screening theories. For large distances, on the other hand, the results agree with linear screening theories provided the charge of the bio-molecules is suitably renormalized.Comment: 18 pages, 18 figures included in text, 100 bibliog
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