527 research outputs found

    Poverty and Illness in the 'Old Countries': archaeological approaches to historical medical institutions in the British Isles.

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    Since the 1990s, archaeological approaches to institutions designed for public health, benefit, and welfare have been developed. Key publications have raised the profile of ‘institutional’ archaeology in North America and Australia, while archaeology-based, and built-environment focused, research in the British Isles has gained momentum. These buildings continue to be grouped under the category of ‘institutional’ architecture, alongside prisons and institutions for confinement, but in light of recent scholarship, homogenisation of institutional buildings is no longer so useful. Focusing on the British Isles, this paper outlines archaeological methodologies that set British and Irish approaches within their unique context, highlighting the distinctiveness of different building types. Focusing on two institutional building types, the asylum and the hospital, the significant difference between these building types and those frequently considered analogous becomes apparent

    Uric acid: an old actor for a new role

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    The role of uric acid as an independent risk factor for cardiovascular events is still debated. In fact, other confounding factors such as glucose intolerance, obesity, dyslipidaemia, hypertension, use of diuretics and insulin resistance may play a role in determining the increased vascular risk associated to elevated uric acid concentrations. These factors (including high uric acid) have been mentioned in one or more definitions of the metabolic syndrome. Recently, much attention has been paid to the metabolic syndrome due to its possible role as a risk factor for the development of type 2 diabetes and cardiovascular disease. The worldwide increase in the prevalence of obesity and diabetes is a reason not only for the increasing prevalence of the metabolic syndrome but also of hyperuricaemia. A better understanding of the role of uric acid in health and in disease states may help physicians to improve their performance in preventing and treating cardiovascular disease

    The Complex Dynamics of Sponsored Search Markets

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    This paper provides a comprehensive study of the structure and dynamics of online advertising markets, mostly based on techniques from the emergent discipline of complex systems analysis. First, we look at how the display rank of a URL link influences its click frequency, for both sponsored search and organic search. Second, we study the market structure that emerges from these queries, especially the market share distribution of different advertisers. We show that the sponsored search market is highly concentrated, with less than 5% of all advertisers receiving over 2/3 of the clicks in the market. Furthermore, we show that both the number of ad impressions and the number of clicks follow power law distributions of approximately the same coefficient. However, we find this result does not hold when studying the same distribution of clicks per rank position, which shows considerable variance, most likely due to the way advertisers divide their budget on different keywords. Finally, we turn our attention to how such sponsored search data could be used to provide decision support tools for bidding for combinations of keywords. We provide a method to visualize keywords of interest in graphical form, as well as a method to partition these graphs to obtain desirable subsets of search terms

    Why does fertilization reduce plant species diversity? Testing three competition-based hypotheses

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    1 Plant species diversity drops when fertilizer is added or productivity increases. To explain this, the total competition hypothesis predicts that competition above ground and below ground both become more important, leading to more competitive exclusion, whereas the light competition hypothesis predicts that a shift from below-ground to above-ground competition has a similar effect. The density hypothesis predicts that more above-ground competition leads to mortality of small individuals of all species, and thus a random loss of species from plots. 2 Fertilizer was added to old field plots to manipulate both below-ground and above-ground resources, while shadecloth was used to manipulate above-ground resources alone in tests of these hypotheses. 3 Fertilizer decreased both ramet density and species diversity, and the effect remained significant when density was added as a covariate. Density effects explained only a small part of the drop in diversity with fertilizer. 4 Shadecloth and fertilizer reduced light by the same amount, but only fertilizer reduced diversity. Light alone did not control diversity, as the light competition hypothesis would have predicted, but the combination of above-ground and below-ground competition caused competitive exclusion, consistent with the total competition hypothesis.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/75695/1/j.1365-2745.2001.00662.x.pd

    Measurement of W Polarisation at LEP

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    The three different helicity states of W bosons produced in the reaction e+ e- -> W+ W- -> l nu q q~ at LEP are studied using leptonic and hadronic W decays. Data at centre-of-mass energies \sqrt s = 183-209 GeV are used to measure the polarisation of W bosons, and its dependence on the W boson production angle. The fraction of longitudinally polarised W bosons is measured to be 0.218 \pm 0.027 \pm 0.016 where the first uncertainty is statistical and the second systematic, in agreement with the Standard Model expectation

    Associations of body size with all-cause and cause-specific mortality in healthy older adults

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    In the general population, body mass index (BMI) and waist circumference are recognized risk factors for several chronic diseases and all-cause mortality. However, whether these associations are the same for older adults is less clear. The association of baseline BMI and waist circumference with all-cause and cause-specific mortality was investigated in 18,209 Australian and US participants (mean age: 75.1 ± 4.5 years) from the ASPirin in Reducing Events in the Elderly (ASPREE) study, followed up for a median of 6.9 years (IQR: 5.7, 8.0). There were substantially different relationships observed in men and women. In men, the lowest risk of all-cause and cardiovascular mortality was observed with a BMI in the range 25.0–29.9 kg/m2 [HR25-29.9 vs 21–24.9 kg/m2: 0.85; 95% CI, 0.73–1.00] while the highest risk was in those who were underweight [HRBMI <21 kg/m2 vs BMI 21–24.9 kg/m2: 1.82; 95% CI 1.30–2.55], leading to a clear U-shaped relationship. In women, all-cause mortality was highest in those with the lowest BMI leading to a J-shaped relationship (HRBMI <21 kg/m2 vs BMI 21–24.9 kg/m2: 1.64; 95% CI 1.26–2.14). Waist circumference showed a weaker relationship with all-cause mortality in both men and women. There was little evidence of a relationship between either index of body size and subsequent cancer mortality in men or women, while non-cardiovascular non-cancer mortality was higher in underweight participants. For older men, being overweight was found to be associated with a lower risk of all-cause mortality, while among both men and women, a BMI in the underweight category was associated with a higher risk. Waist circumference alone had little association with all-cause or cause-specific mortality risk. Trial registration ASPREE https://ClinicalTrials.gov number NCT01038583.Prudence R. Carr, Katherine L. Webb, Johannes T. Neumann, Le T. P. Thao, Lawrence J. Beilin, Michael E. Ernst, Bernadette Fitzgibbon, Danijela Gasevic, Mark R. Nelson, Anne B. Newman, Suzanne G. Orchard, Alice Owen, Christopher M. Reid, Nigel P. Stocks, Andrew M. Tonkin, Robyn L. Woods, John J. McNei

    Search for Anomalous Couplings in the Higgs Sector at LEP

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    Anomalous couplings of the Higgs boson are searched for through the processes e^+ e^- -> H gamma, e^+ e^- -> e^+ e^- H and e^+ e^- -> HZ. The mass range 70 GeV < m_H < 190 GeV is explored using 602 pb^-1 of integrated luminosity collected with the L3 detector at LEP at centre-of-mass energies sqrt(s)=189-209 GeV. The Higgs decay channels H -> ffbar, H -> gamma gamma, H -> Z\gamma and H -> WW^(*) are considered and no evidence is found for anomalous Higgs production or decay. Limits on the anomalous couplings d, db, Delta(g1z), Delta(kappa_gamma) and xi^2 are derived as well as limits on the H -> gamma gamma and H -> Z gamma decay rates

    Measurement of W Polarisation at LEP

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    The three different helicity states of W bosons produced in the reaction e+ e- -> W+ W- -> l nu q q~ at LEP are studied using leptonic and hadronic W decays. Data at centre-of-mass energies \sqrt s = 183-209 GeV are used to measure the polarisation of W bosons, and its dependence on the W boson production angle. The fraction of longitudinally polarised W bosons is measured to be 0.218 \pm 0.027 \pm 0.016 where the first uncertainty is statistical and the second systematic, in agreement with the Standard Model expectation

    Bose-Einstein Correlations of Neutral and Charged Pions in Hadronic Z Decays

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    Bose-Einstein correlations of both neutral and like-sign charged pion pairs are measured in a sample of 2 million hadronic Z decays collected with the L3 detector at LEP. The analysis is performed in the four-momentum difference range 300 MeV < Q < 2 GeV. The radius of the neutral pion source is found to be smaller than that of charged pions. This result is in qualitative agreement with the string fragmentation model

    Z Boson Pair-Production at LEP

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    Events stemming from the pair-production of Z bosons in e^+e^- collisions are studied using 217.4 pb^-1 of data collected with the L3 detector at centre-of-mass energies from 200 GeV up to 209 GeV. The special case of events with b quarks is also investigated. Combining these events with those collected at lower centre-of-mass energies, the Standard Model predictions for the production mechanism are verified. In addition, limits are set on anomalous couplings of neutral gauge bosons and on effects of extra space dimensions
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