76 research outputs found

    Elections as beauty contests: do the rules matter?

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    Leaders have become the human face of election campaigns. This has lead to the suggestion that many voters now vote for the party leader they like best rather than the party they prefer. However, people would seem more likely to vote for the leader rather than the party in presidential elections rather than parliamentary ones, and amongst parliamentary elections themselves when a majoritarian rather than proportional electoral system is used. In addition we might expect these propositions to be particularly true if few people have a strong party identification and many people watch a lot of television news. This paper uses the Comparative Study of Electoral Systems project data to assess whether there is any systematic evidence to support these expectations

    Global Optimization on an Evolving Energy Landscape

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    Locating the global minimum of a complex potential energy surface is facilitated by considering a homotopy, namely a family of surfaces that interpolate continuously from an arbitrary initial potential to the system under consideration. Different strategies can be used to follow the evolving minima. It is possible to enhance the probability of locating the global minimum through a heuristic choice of interpolation schemes and parameters, and the continuously evolving potential landscape reduces the probability of trapping in local minima. In application to a model problem, finding the ground--state configuration and energy of rare--gas (Lennard--Jones) atomic clusters, we demonstrate the utility and efficacy of this method

    Global Optimization by Adiabatic Switching

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    We apply a recently introduced method for global optimization to determine the ground state energy and configuration for model metallic clusters. The global minimum for a given N-atom cluster is found by following the damped dynamics of the N particle system on an evolving potential energy surface. In this application, the time dependent interatomic potential interpolates adiabatically between the Lennard-Jones (LJ) and the Sutton-Chen (SC) forms. Starting with an ensemble of initial conditions corresponding to the ground state configuration of the Lennard-Jones cluster, the system asymptotically reaches the ground state of the Sutton-Chen cluster. We describe the method and present results for specific cluster size N=15, when the ground state symmetry of LJN_N and SCN_N differ

    Influence of nitrogen on guttation fluid and development of bacterial blight of rice

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    Bacterial blight disease of rice is major constraint in rice cultivation. This disease is influenced by prevailing weather conditions, rice physiology and nutrition. The experiment was carried out to assess the role of nitrogenous fertilizer on development of bacterial blight disease of rice and Xanthomonas oryzae pv. oryzae density in guttation fluid. Disease development increased with increase in nitrogen fertilizer, among four doses of nitrogen tested (control, 36, 54,72 kg urea/acre), disease severity was maximum in the plot supplied with highest dose of nitrogen i.e. 72 kg urea/acre at both seedling (19.3%) and tillering stage (32.4%) at 30 days after inoculation. The highest population density of X. oryzae pv. oryzae (6.02 log cfu/ml) was also recovered in guttation fluid collected from X.oryzaepv. oryzae inoculated plants at tillering stage, from the plots supplied with highest dose (72 kg urea/acre) of nitrogen.Scanning electron microscopic studies also revealed intense colonization by X. oryzae pv. oryzae in rice leaves supplied with high nitrogen dose

    Knowledge of current abortion law and views on abortion law reform: a community survey of NSW residents

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    Objective: To report results of a community survey of NSW residents' knowledge of current abortion law and views on abortion law reform. Methods: A total of 1,015 men and women participated. Recruitment and questionnaires were completed anonymously online using survey panel sampling. Results: Seventy-six per cent of respondents were unaware that abortion remains a criminal offence in the Crimes Act 1900 (NSW) and 73% thought it should be decriminalised and regulated as a healthcare service. Support for decriminalisation was consistent across genders, age groups, residents of metropolitan/regional and rural areas and levels of education. Support was strong for women seeking abortion to be protected from harassment (89%) and for protester exclusion zones around clinics (81%), with support for these measures significantly stronger among regional/rural residents than Sydney-based respondents. Conclusions: Abortion law in NSW is out of step with contemporary community views. Residents are largely unaware that it remains a criminal offence and, when informed, support decriminalisation. There is strong support for legal changes to protect women from harassment and to provide protester exclusion zones around abortion clinics. Implications for public health: Abortion law reform would reduce current inequities of access, be democratic and support women's autonomy and reproductive rights

    Expression of a hindlimb-determining factor Pitx1 in the forelimb of the lizard Pogona vitticeps during morphogenesis

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    With over 9000 species, squamates, which include lizards and snakes, are the largest group of reptiles and second-largest order of vertebrates, spanning a vast array of appendicular skeletal morphology. As such, they provide a promising system for examining developmental and molecular processes underlying limb morphology. Using the central bearded dragon (Pogona vitticeps) as the primary study model, we examined limb morphometry throughout embryonic development and characterized the expression of three known developmental genes (GHR, Pitx1 and Shh) from early embryonic stage through to hatchling stage via reverse transcription quantitative polymerase chain reaction (RT-qPCR) and immunohistochemistry (IHC). In this study, all genes were found to be transcribed in both the forelimbs and hindlimbs of P. vitticeps. While the highest level of GHR expression occurred at the hatchling stage, Pitx1 and Shh expression was greatest earlier during embryogenesis, which coincides with the onset of the differentiation between forelimb and hindlimb length. We compared our finding of Pitx1 expression-a hindlimb-determining gene-in the forelimbs of P. vitticeps to that in a closely related Australian agamid lizard, Ctenophorus pictus, where we found Pitx1 expression to be more highly expressed in the hindlimb compared with the forelimb during early and late morphogenesis-a result consistent with that found across other tetrapods. Expression of Pitx1 in forelimbs has only rarely been documented, including via in situ hybridization in a chicken and a frog. Our findings from both RT-qPCR and IHC indicate that further research across a wider range of tetrapods is needed to more fully understand evolutionary variation in molecular processes underlying limb morphology.Jane Melville, Sumitha Hunjan, Felicity McLean, Georgia Mantziou, Katja Boysen and Laura J. Parr

    Health inequalities, fundamental causes and power:Towards the practice of good theory

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    Reducing health inequalities remains a challenge for policy makers across the world. Beginning from Lewin’s famous dictum that “there is nothing as practical as a good theory”, this paper begins from an appreciative discussion of ‘fundamental cause theory’, emphasizing the elegance of its theoretical encapsulation of the challenge, the relevance of its critical focus for action, and its potential to support the practical mobilisation of knowledge in generating change. Moreover, it is argued that recent developments in the theory, provide an opportunity for further theoretical development focused more clearly on the concept of power (Dickie et al. 2015). A critical focus on power as the essential element in maintaining, increasing or reducing social and economic inequalities – including health inequalities – can both enhance the coherence of the theory, and also enhance the capacity to challenge the roots of health inequalities at different levels and scales. This paper provides an initial contribution by proposing a framework to help to identify the most important sources, forms and positions of power, as well as the social spaces in which they operate. Subsequent work could usefully test, elaborate and adapt this framework, or indeed ultimately replace it with something better, to help focus actions to reduce inequalities

    Performance of [(18)F]flutemetamol amyloid imaging against the neuritic plaque component of CERAD and the current (2012) NIA-AA recommendations for the neuropathologic diagnosis of Alzheimer's disease

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    INTRODUCTION: Performance of the amyloid tracer [(18)F]flutemetamol was evaluated against three pathology standard of truth (SoT) measures including neuritic plaques (CERAD "original" and "modified" and the amyloid component of the 2012 NIA-AA guidelines). METHODS: After [(18)F]flutemetamol imaging, 106 end-of-life patients who died underwent postmortem brain examination for amyloid plaque load. Blinded positron emission tomography scan interpretations by five independent electronically trained readers were compared with pathology measures. RESULTS: By SoT, sensitivity and specificity of majority image interpretations were, respectively, 91.9% and 87.5% with "original CERAD," 90.8% and 90.0% with "modified CERAD," and 85.7% and 100% with the 2012 NIA-AA criteria. DISCUSSION: The high accuracy of either CERAD criteria suggests that [(18)F]flutemetamol predominantly reflects neuritic amyloid plaque density. However, the use of CERAD criteria as the SoT can result in some false-positive results because of the presence of diffuse plaques, which are accounted for when the positron emission tomography read is compared with the 2012 NIA-AA criteria

    FSH requirements for follicle growth during controlled ovarian stimulation

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    This paper presents independent research funded by grants from the MRC, BBSRC, and NIHR and supported by the NIHR/Wellcome Trust Imperial Clinical Research Facility and Imperial Biomedical Research Centre. The Section of Endocrinology and Investigative Medicine was funded by grants from the MRC, BBSRC, NIHR and was supported by the NIHR Biomedical Research Centre Funding Scheme. AA was supported by National Institute of Health Research (NIHR) Clinician Scientist Award CS-2018-18-ST2-002. SC was supported by funding from an NIHR Academic Clinical Lectureship. WD was supported by an NIHR Research Professorship NIHR-RP-2014-05-001. TK was supported by EPSRC EP/P015638/1. The Medical Research Council (MRC), Wellcome Trust & National Institute of Health Research (NIHR) provided research funding to carry out studies using kisspeptin.Introduction: Ovarian follicle growth is a key step in the success of assisted reproductive treatment, but limited data exists to directly relate follicle growth to recombinant FSH (rFSH) dose. In this study, we aim to evaluate FSH requirements for follicular growth during controlled ovarian stimulation. Method: Single center retrospective cohort study of 1,034 IVF cycles conducted between January 2012–January 2016 at Hammersmith Hospital IVF unit, London, UK. Median follicle size after 5 days of stimulation with rFSH and the proportion of antral follicles recruited were analyzed in women treated with rFSH alone to induce follicular growth during IVF treatment. Results: Starting rFSH dose adjusted for body weight (iU/kg) predicted serum FSH level after 5 days of rFSH (r2 = 0.352, p 5% dose-increase was associated with increased variability in follicle size on the day of oocyte maturation trigger, and negatively impacted the number of mature oocytes retrieved. Conclusion: Weight-adjusted rFSH dose correlates with follicular growth during ovarian stimulation. Early recruitment of follicles using a sufficient dose of rFSH from the start of stimulation was associated with reduced variability in follicle size at time of oocyte maturation trigger and an increased number of mature oocytes retrieved.Publisher PDFPeer reviewe

    ‘Test n Treat (TnT)’– Rapid testing and same-day, on-site treatment to reduce rates of chlamydia in sexually active further education college students: study protocol for a cluster randomised feasibility trial

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    Background Sexually active young people attending London further education (FE) colleges have high rates of chlamydia, but screening rates are low. We will conduct a cluster randomised feasibility trial of frequent, rapid, on-site chlamydia testing and same-day treatment (Test and Treat (TnT)) in six FE colleges (with parallel qualitative and economic assessments) to assess the feasibility of conducting a future trial to investigate if TnT reduces chlamydia rates. Methods We will recruit 80 sexually active students aged 16–24 years from public areas at each of six colleges. All participants (total n = 480) will be asked to provide samples (urine for males, self-taken vaginal swabs for females) and complete questionnaires on sexual lifestyle and healthcare use at baseline and after 7 months. Participants will be informed that baseline samples will not be tested for 7 months and be advised to get screened separately. Colleges will be randomly allocated to the intervention (TnT) or the control group (no TnT). One and 4 months after recruitment, participants at each intervention college (n = 3) will be texted and invited for on-site chlamydia tests using the 90-min Cepheid GeneXpert system. Students with positive results will be asked to see a visiting nurse health adviser for same-day treatment and partner notification, (backed by genitourinary medicine follow-up). Participants in control colleges (n = 3) will receive ‘thank you’ texts 1 and 4 months after recruitment. Seven months after recruitment, participants from both groups will be invited to complete questionnaires and provide samples for TnT. All samples will be tested, and same-day treatment offered to students with positive results. Acceptability of TnT will be assessed by qualitative interviews of purposively sampled students (n = 30) and college staff (n = 12). We will collect data on costs of TnT and usual healthcare. Discussion Findings will provide key values to inform feasibility, sample size and timescales of a future definitive trial of TnT in FE colleges, including: Recruitment rates TnT uptake rates Follow-up rates Prevalence of chlamydia in participants at baseline and 7 months Acceptability of TnT to students and college staff Estimate of the cost per person screened/treated in TnT versus usual care Trial registration International Standard Randomised Controlled Trials Registry, ID: ISRCTN58038795, Registered on 31 August 2016
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