300 research outputs found

    Using a sclerochronological approach to determine a climate-growth relationship for waved whelk, Buccinum undatum, in the U.S. Mid-Atlantic

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    Using growth rings observed in statoliths, the size-at-age relationship was modeled for waved whelk (Buccinum undatum) populations within the Mid-Atlantic Bight. A total of 45 sites in the Mid-Atlantic were sampled between 2016 and 2019 using a scallop dredge, and a subset of the whelk collected were aged (n = 318). Lab-reared individuals and back-calculation methods were used to fill missing juvenile observations. The Mid-Atlantic Bight population appears to differ in the fit of growth curves, compared to other assessed populations, due to a timing difference in hatching. Growth curves for whelk from the Mid-Atlantic Bight show that maturity is reached between 4 and 6 years of age. A statolith chronology spanning a 10-year period was developed using a mixed-effects modeling approach. The chronology was used to explore the influence of temperature variation on growth during ecologically relevant periods. Growth increased with higher annual temperatures however specific seasonal bottom temperature had varying effects on growth. Increasing bottom temperature during summer, the anticipated egg-development and hatching period in this region, resulted in an age-dependent decline in growth with a positive effect on younger whelk and a negative effect on older whelk growth. Higher summer temperatures provide larger time-windows for growth, facilitating increased growth in early life stages. It appears that whelk in this region possess sufficient growth plasticity to adapt to warmer conditions throughout the year, but increased warming during specific seasons may depress growth in older individuals, potentially affecting fitness and population persistence. Understanding these temperature-growth dynamics are critical for disentangling the effects of climate change on whelk growth, allowing for population predictions in the future

    Enhancing the ecosystem approach for the fishery for Antarctic krill within the complex, variable and changing ecosystem at South Georgia

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    The objective of the ecosystem approach to fisheries management is to sustain healthy marine ecosystems and the fisheries they support. One of the earliest implementations was in the Southern Ocean, where decision rules and stock reference points were developed for managing the Antarctic krill fishery, together with an ecosystem-monitoring programme intended to aid management decisions. This latter component has not been incorporated directly into management, so here, we consider variability in the krill fishery at South Georgia, relating it to physical and biological monitoring indices, finding sea surface temperature to be a key correlate with both annual catch and long-term biological indices. Some indices from krill predators showed significant positive relationships with krill harvesting in the preceding winter, presumably indicative of the importance of winter foraging conditions. We explore how ecological structure affects results, examining two monitoring sites 100 km apart. Results suggest different biological conditions at the two sites, probably reflecting different scales of ecosystem operation, emphasizing that an appreciation of scale will enhance krill fishery management. Finally, in reviewing different drivers of ecological change, we identify important additional monitoring that would help better reflect ecosystem status, improve the utility of CEMP, providing information necessary for the ecosystem approach at South Georgia

    The alarms should no longer be ignored: survey of the demand, capacity and provision of adult community eating disorder services in England and Scotland before COVID-19.

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    This national pre-pandemic survey compared demand and capacity of adult community eating disorder services (ACEDS) with NHS England (NHSE) commissioning guidance. Thirteen services in England and Scotland responded (covering 10.7 million population). Between 2016-2017 and 2019-2020 mean referral rates increased by 18.8%, from 378 to 449/million population. Only 3.7% of referrals were from child and adolescent eating disorder services (CEDS-CYP), but 46% of patients were aged 18-25 and 54% were aged >25. Most ACEDS had waiting lists and rationed access. Many could not provide full medical monitoring, adapt treatment for comorbidities, offer assertive outreach or provide seamless transitions. For patient volume, the ACEDS workforce budget was 15%, compared with the NHSE workforce calculator recommendations for CEDS-CYP. Parity required £7 million investment/million population for the ACEDS. This study highlights the severe pressure in ACEDS, which has increased since the COVID-19 pandemic. Substantial investment is required to ensure NHS ACEDS meet national guidance, offer evidence-based treatment, reduce risk and preventable deaths, and achieve parity with CEDS-CYP

    Standalone vertex finding in the ATLAS muon spectrometer

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    A dedicated reconstruction algorithm to find decay vertices in the ATLAS muon spectrometer is presented. The algorithm searches the region just upstream of or inside the muon spectrometer volume for multi-particle vertices that originate from the decay of particles with long decay paths. The performance of the algorithm is evaluated using both a sample of simulated Higgs boson events, in which the Higgs boson decays to long-lived neutral particles that in turn decay to bbar b final states, and pp collision data at √s = 7 TeV collected with the ATLAS detector at the LHC during 2011

    Measurements of Higgs boson production and couplings in diboson final states with the ATLAS detector at the LHC

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    Measurements are presented of production properties and couplings of the recently discovered Higgs boson using the decays into boson pairs, H →γ γ, H → Z Z∗ →4l and H →W W∗ →lνlν. The results are based on the complete pp collision data sample recorded by the ATLAS experiment at the CERN Large Hadron Collider at centre-of-mass energies of √s = 7 TeV and √s = 8 TeV, corresponding to an integrated luminosity of about 25 fb−1. Evidence for Higgs boson production through vector-boson fusion is reported. Results of combined fits probing Higgs boson couplings to fermions and bosons, as well as anomalous contributions to loop-induced production and decay modes, are presented. All measurements are consistent with expectations for the Standard Model Higgs boson

    Measurement of the top quark-pair production cross section with ATLAS in pp collisions at \sqrt{s}=7\TeV

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    A measurement of the production cross-section for top quark pairs(\ttbar) in pppp collisions at \sqrt{s}=7 \TeV is presented using data recorded with the ATLAS detector at the Large Hadron Collider. Events are selected in two different topologies: single lepton (electron ee or muon μ\mu) with large missing transverse energy and at least four jets, and dilepton (eeee, μμ\mu\mu or eμe\mu) with large missing transverse energy and at least two jets. In a data sample of 2.9 pb-1, 37 candidate events are observed in the single-lepton topology and 9 events in the dilepton topology. The corresponding expected backgrounds from non-\ttbar Standard Model processes are estimated using data-driven methods and determined to be 12.2±3.912.2 \pm 3.9 events and 2.5±0.62.5 \pm 0.6 events, respectively. The kinematic properties of the selected events are consistent with SM \ttbar production. The inclusive top quark pair production cross-section is measured to be \sigmattbar=145 \pm 31 ^{+42}_{-27} pb where the first uncertainty is statistical and the second systematic. The measurement agrees with perturbative QCD calculations.Comment: 30 pages plus author list (50 pages total), 9 figures, 11 tables, CERN-PH number and final journal adde

    Measurement of the top quark pair cross section with ATLAS in pp collisions at √s=7 TeV using final states with an electron or a muon and a hadronically decaying τ lepton

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    A measurement of the cross section of top quark pair production in proton-proton collisions recorded with the ATLAS detector at the Large Hadron Collider at a centre-of-mass energy of 7 TeV is reported. The data sample used corresponds to an integrated luminosity of 2.05 fb -1. Events with an isolated electron or muon and a τ lepton decaying hadronically are used. In addition, a large missing transverse momentum and two or more energetic jets are required. At least one of the jets must be identified as originating from a b quark. The measured cross section, σtt-=186±13(stat.)±20(syst.)±7(lumi.) pb, is in good agreement with the Standard Model prediction

    Hunt for new phenomena using large jet multiplicities and missing transverse momentum with ATLAS in 4.7 fb−1 of √s=7 TeV proton-proton collisions

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    Results are presented of a search for new particles decaying to large numbers of jets in association with missing transverse momentum, using 4.7 fb−1 of pp collision data at s√=7TeV collected by the ATLAS experiment at the Large Hadron Collider in 2011. The event selection requires missing transverse momentum, no isolated electrons or muons, and from ≥6 to ≥9 jets. No evidence is found for physics beyond the Standard Model. The results are interpreted in the context of a MSUGRA/CMSSM supersymmetric model, where, for large universal scalar mass m 0, gluino masses smaller than 840 GeV are excluded at the 95% confidence level, extending previously published limits. Within a simplified model containing only a gluino octet and a neutralino, gluino masses smaller than 870 GeV are similarly excluded for neutralino masses below 100 GeV

    Costs analysis of the treatment of imported malaria

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    <p>Abstract</p> <p>Background</p> <p>To document the status of imported malaria infections and estimate the costs of treating of patients hospitalized with the diagnosis of imported malaria in the Slovak Republic during 2003 to 2008.</p> <p>Case study</p> <p>Calculating and comparing the direct and indirect costs of treatment of patients diagnosed with imported malaria (ICD-10: B50 - B54) who used and not used chemoprophylaxis. The target sample included 19 patients diagnosed with imported malaria from 2003 to 2008, with 11 whose treatment did not include chemoprophylaxis and eight whose treatment did.</p> <p>Results</p> <p>The mean direct cost of malaria treatment for patients without chemoprophylaxis was 1,776.0 EUR, and the mean indirect cost 524.2 EUR. In patients with chemoprophylaxis the mean direct cost was 405.6 EUR, and the mean indirect cost 257.4 EUR.</p> <p>Conclusions</p> <p>The analysis confirmed statistically-significant differences between the direct and indirect costs of treatment with and without chemoprophylaxis for patients with imported malaria.</p

    Measurement of the inclusive isolated prompt photon cross-section in pp collisions at sqrt(s)= 7 TeV using 35 pb-1 of ATLAS data

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    A measurement of the differential cross-section for the inclusive production of isolated prompt photons in pp collisions at a center-of-mass energy sqrt(s) = 7 TeV is presented. The measurement covers the pseudorapidity ranges |eta|<1.37 and 1.52<=|eta|<2.37 in the transverse energy range 45<=E_T<400GeV. The results are based on an integrated luminosity of 35 pb-1, collected with the ATLAS detector at the LHC. The yields of the signal photons are measured using a data-driven technique, based on the observed distribution of the hadronic energy in a narrow cone around the photon candidate and the photon selection criteria. The results are compared with next-to-leading order perturbative QCD calculations and found to be in good agreement over four orders of magnitude in cross-section.Comment: 7 pages plus author list (18 pages total), 2 figures, 4 tables, final version published in Physics Letters
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