11,113 research outputs found

    Adaptive primal-dual genetic algorithms in dynamic environments

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    This article is placed here with permission of IEEE - Copyright @ 2010 IEEERecently, there has been an increasing interest in applying genetic algorithms (GAs) in dynamic environments. Inspired by the complementary and dominance mechanisms in nature, a primal-dual GA (PDGA) has been proposed for dynamic optimization problems (DOPs). In this paper, an important operator in PDGA, i.e., the primal-dual mapping (PDM) scheme, is further investigated to improve the robustness and adaptability of PDGA in dynamic environments. In the improved scheme, two different probability-based PDM operators, where the mapping probability of each allele in the chromosome string is calculated through the statistical information of the distribution of alleles in the corresponding gene locus over the population, are effectively combined according to an adaptive Lamarckian learning mechanism. In addition, an adaptive dominant replacement scheme, which can probabilistically accept inferior chromosomes, is also introduced into the proposed algorithm to enhance the diversity level of the population. Experimental results on a series of dynamic problems generated from several stationary benchmark problems show that the proposed algorithm is a good optimizer for DOPs.This work was supported in part by the National Nature Science Foundation of China (NSFC) under Grant 70431003 and Grant 70671020, by the National Innovation Research Community Science Foundation of China under Grant 60521003, by the National Support Plan of China under Grant 2006BAH02A09, by the Engineering and Physical Sciences Research Council (EPSRC) of U.K. under Grant EP/E060722/1, and by the Hong Kong Polytechnic University Research Grants under Grant G-YH60

    Gradients and anisotropies of high energy cosmic rays in the outer heliosphere

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    Previous studies at lower energies have shown that the cosmic ray density gradients vary in space and time, and many authors currently are suggesting that the radial gradient associated with solar cycle modulation is supported largely by narrow barriers which encircle the Sun and propagate outward with the solar wind. If so, the anisotropy is a desirable way to detect spatial gradients, because it can be associated with the local solar wind and magnetic field conditions. With this in mind, the anisotropy measurements made by the UCSD Cerenkov detectors on Pioneers 10 and 11 are studied. It is shown that the local anisotropy varies greatly, but that the long term average is consistent with the global radial gradient measured between two spacecraft over a baseline of many AU

    Gradients and anisotropies of high energy cosmic rays in the outer heliosphere

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    Two cosmic rays which pass through the same point going in opposite directions will, in the absence of scattering and inhomogeneities in the magnetic field, trace helices about adjacent flux tubes, whose centerlines are separated by one gyrodiameter. A directional anisotropy at the point suggests a difference in the number of cosmic rays loading the two flux tubes; that is, a density gradient over the baseline of a gyrodiameter. Previous studies at lower energies have shown that the cosmic ray density gradients vary in time and space. It is suggested that the radial gradient associated with solar cycle modulation is supported largely by narrow barriers which encircle the sun and propagate outward with the solar wind. If so, the anisotropy is a desirable way to detect spatial gradients, because it can be associated with the local solar wind and magnetic field conditions. Anisotropic measurements made by Cerenkov detectors on Pioneers 10 and 11 were studied. It was found that local anisotropy varies greatly, but that the long term average is consistent with the global radial gradient measured between two spacecraft over a baseline of many AU

    Coenzyme Q10 supplementation in non alcoholic liver disease: an overview.

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    Non-alcoholic fatty liver disease (NAFLD) is the most common liver disorder in the UK, for which little effective conventional treatment is available. Mitochondrial dysfunction, oxidative stress and inflammation have been implicated in the pathogenesis of NAFLD. This article focuses on the role of the vitamin-like substance coenzyme Q10 (CoQ10) in NAFLD, since CoQ10 plays a key role in mitochondrial function, as well as having antioxidant and anti-inflammatory action. CoQ10 levels are depleted in NAFLD, and studies in animal models and human subjects have indicated that supplementation with CoQ10 can significantly reduce oxidative stress and the inflammation characteristic of NAFLD. In addition, NAFLD patients are at increased risk of developing heart failure, and supplementary CoQ10 may help to reduce this risk. Supplementary CoQ10 is generally well tolerated, with no significant adverse effects reported in long-term use

    Particle acceleration and the origin of gamma-ray emission from Fermi Bubbles

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    Fermi LAT has discovered two extended gamma-ray bubbles above and below the galactic plane. We propose that their origin is due to the energy release in the Galactic center (GC) as a result of quasi-periodic star accretion onto the central black hole. Shocks generated by these processes propagate into the Galactic halo and accelerate particles there. We show that electrons accelerated up to ~10 TeV may be responsible for the observed gamma-ray emission of the bubbles as a result of inverse Compton (IC) scattering on the relic photons. We also suggest that the Bubble could generate the flux of CR protons at energies > 10^15 eV because the shocks in the Bubble have much larger length scales and longer lifetimes in comparison with those in SNRs. This may explain the the CR spectrum above the knee.Comment: 5 pages, 4 figures. Expanded version of the contribution to the 32nd ICRC, Beijing, #0589. To appear in the proceeding

    Hong Kong\u27s Failure to Extradite Edward Snowden: More Than Just a Technical Defect

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    As the Edward Snowden case takes legs and exhibits all the earmarks of official misconduct and scandal, the U.S. government continues efforts aimed at extraditing this whistleblower, characterizing him as a traitor and doing damage control in the NSA. Part of this strategy includes intimidating those sovereign states that refuse to coooperate in returning Snowden to face trial.Yet, the legal basis for these U.S. efforts is highly contentious. If Snowden had stayed in Hong Kong and fought extradition, in all likelihood he would have prevailed. Thus, the U.S. is left with not credible basis for complaint, and its retaliatory diplomatic measures against other states are without merit. This essay reviews Snowden\u27s defenses under the double criminality principle and the political offense exception according to Hong Kong law, applying the British incidence standard,and casts light on a self defeating U.S. Policy

    Study protocol for a randomised controlled trial of Allen Carr's Easyway programme versus Lambeth and Southwark NHS for smoking cessation.

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    INTRODUCTION: Smoking is a major cause of ill health and is associated with several diseases including cancer, coronary heart disease and stroke. Many psychological and pharmacological smoking cessation treatments are available and although they are undoubtedly the most cost-effective health interventions available, many people still fail to maintain cessation in the longer term. Recently, National Institute for Health and Care Excellence called for comparative studies to determine the short-term and long-term effectiveness of Allen Carr's Easyway (ACE) method of stopping smoking. This study will compare the efficacy of the ACE programme and a 1-1 counselling service available via the National Health Service. METHODS AND ANALYSIS: A two-arm, parallel-group, blinded, randomised controlled trial will be conducted with people who smoke tobacco cigarettes, are aged ≥18 years and are motivated to quit. Exclusion criteria comprise self-reported mental health condition, pregnancy or respiratory disease such as chronic obstructive pulmonary disease or emphysema. The primary treatment outcome is smoking cessation 26 weeks after treatment. Participants will be analysed on an intention to treat basis at the point of randomisation. Before being randomised, the research team will not inform participants which two treatments are being compared. Once randomised researchers will be blinded to participant condition, and participants will be blinded to the condition they are not assigned to. Logistic regression will be used to estimate the effectiveness of the treatment condition on smoking cessation at 26 weeks. The following covariates will be included: baseline quit efficacy (at inclusion), age (at inclusion), gender and baseline nicotine dependency. ETHICS AND DISSEMINATION: Approval was granted by London-Fulham Research Ethics Committee (ref: 16/LO/1657). The study's findings will be published in peer-reviewed journals and disseminated at national and international conferences. TRIAL REGISTRATION NUMBER: ClinicalTrials.gov identifier number: NCT02855255. ISRCTN registration number: ISRCTN23584477; Pre-results

    EBUS-TBNA gives adequate tissue information on cell type in lung cancer

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    INTRODUCTION: In formulating systemic treatment in patients with advanced stage lung cancer, it is now considered imperative to know the cell type such as squamous carcinoma, adenocarcinoma and large cell carcinoma as chemotherapeutic agents would be tailored to treat different cell types. In the authors’ centre, the adoption of using epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKI) as the firstline treatment has been the treatment of choice in patients shown to have activated EGFR mutation. Adequate tissue obtained during diagnostic procedures for cell typing and molecular profiling is therefore important in formulating personalised treatment in lung cancer patients nowa…published_or_final_versio

    Long-term efficacy of an education programme in improving adherence with continuous positive airway pressure treatment for obstructive sleep apnoea

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    This randomised controlled trial demonstrated that a motivational enhancement programme composed of a single interview and a follow-up phone call at the initiation of continuous positive airway pressure treatment can improve treatment adherence in subjects with obstructive sleep apnoea, even after 1 year, and lead to better health outcome in terms of reducing daytime sleepiness.published_or_final_versio

    Disorders of Human Coenzyme Q10 Metabolism: An Overview

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    Coenzyme Q10 (CoQ10) has a number of vital functions in all cells, both mitochondrial and extramitochondrial. In addition to its key role in mitochondrial oxidative phosphorylation, CoQ10 serves as a lipid soluble antioxidant, plays an important role in fatty acid, pyrimidine and lysosomal metabolism, as well as directly mediating the expression of a number of genes, including those involved in inflammation. In view of the central role of CoQ10 in cellular metabolism, it is unsurprising that a CoQ10 deficiency is linked to the pathogenesis of a range of disorders. CoQ10 deficiency is broadly classified into primary or secondary deficiencies. Primary deficiencies result from genetic defects in the multi-step biochemical pathway of CoQ10 synthesis, whereas secondary deficiencies can occur as result of other diseases or certain pharmacotherapies. In this article we have reviewed the clinical consequences of primary and secondary CoQ10 deficiencies, as well as providing some examples of the successful use of CoQ10 supplementation in the treatment of disease
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