3,333 research outputs found

    Reproductive ecology of Lophelia pertusa in Mingulay Reef and the Logachev mounds (North East Atlantic): a multi‐scale comparison

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    This paper presents the results of a multi-scale comparison in the reproductive stage of the cold-water coral Lophelia pertusa in two areas of the North-east Atlantic: The Mingulay Reef and the Logachev Mounds. The study was carried out during the Research cruise “Changing Oceans” on board of the RRV James Cook, conducted in May-June 2012. The comparative study between the two geographical areas revealed higher fecundity for the colonies analysed from Mingulay Reef compared to the colonies from the Logachev mounds. Moreover the development stage of the oocytes was more advanced in the colonies sampled from Mingulay than in the ones collected from Logachev. The comparison between single colonies and within the same colony from the Mingulay Reef did not show any differences in the maturity stage of the oocytes, nevertheless the analyses of the reproductive stage between mesenteries within the same polyps showed high variability, which indicates that the gametogenic development within each mesentery undergoes a prolonged period of oocyte production. This probably results in a protracted spawning period, which might improve the reproductive success of the species. This work has been developed under the framework of the UKOA program (United Kingdom Ocean Acidification program) and has been supported by the National Environmental Research Council (NERC, UK)

    Consortium for the Study of Pregnancy Treatments (Co-OPT): An international birth cohort to study the effects of antenatal corticosteroids

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    BACKGROUND: Antenatal corticosteroids (ACS) are widely prescribed to improve outcomes following preterm birth. Significant knowledge gaps surround their safety, long-term effects, optimal timing and dosage. Almost half of women given ACS give birth outside the "therapeutic window" and have not delivered over 7 days later. Overtreatment with ACS is a concern, as evidence accumulates of risks of unnecessary ACS exposure. METHODS: The Consortium for the Study of Pregnancy Treatments (Co-OPT) was established to address research questions surrounding safety of medications in pregnancy. We created an international birth cohort containing information on ACS exposure and pregnancy and neonatal outcomes by combining data from four national/provincial birth registers and one hospital database, and follow-up through linked population-level data from death registers and electronic health records. RESULTS AND DISCUSSION: The Co-OPT ACS cohort contains 2.28 million pregnancies and babies, born in Finland, Iceland, Israel, Canada and Scotland, between 1990 and 2019. Births from 22 to 45 weeks' gestation were included; 92.9% were at term (≥ 37 completed weeks). 3.6% of babies were exposed to ACS (67.0% and 77.9% of singleton and multiple births before 34 weeks, respectively). Rates of ACS exposure increased across the study period. Of all ACS-exposed babies, 26.8% were born at term. Longitudinal childhood data were available for 1.64 million live births. Follow-up includes diagnoses of a range of physical and mental disorders from the Finnish Hospital Register, diagnoses of mental, behavioural, and neurodevelopmental disorders from the Icelandic Patient Registers, and preschool reviews from the Scottish Child Health Surveillance Programme. The Co-OPT ACS cohort is the largest international birth cohort to date with data on ACS exposure and maternal, perinatal and childhood outcomes. Its large scale will enable assessment of important rare outcomes such as perinatal mortality, and comprehensive evaluation of the short- and long-term safety and efficacy of ACS

    Consortium for the Study of Pregnancy Treatments (Co-OPT) : An international birth cohort to study the effects of antenatal corticosteroids

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    Acknowledgments We are grateful to the Co-OPT collaborators from Finland, Iceland, Israel, Nova Scotia, and Scotland, who have provided high-quality patient data, without which the Co-OPT ACS cohort would not have been possible. We acknowledge Public Health Scotland for providing us with a secure data analytical platform in which to undertake this research and are particularly grateful to Anna Schneider who has been the data controller for this project. Co-OPT collaborators: Karel Allegaert (Belgium), Jasper Been (Netherlands), David Burgner (Australia), Sohinee Bhattacharya (UK), Kate Duhig (UK), Kristjana EinarsdĂłttir (Iceland), John Fahey (Canada), Lani Florian (UK), Abigail Fraser (UK), Mika Gissler (Finland), Cynthia Gyamfi-Bannerman (USA), Bo Jacobsson (Sweden), Eyal Krispin (Israel), Stefan Kuhle (Canada), Marius Lahti-Pulkkinen (Finland), Jessica Miller (Australia), Ben Mol (Australia), Sarah Murray (UK), Jane Norman (UK), Lars Henning Pedersen (Denmark), Richard Riley (UK), Devender Roberts (UK), Ewoud Schuit (Netherlands), Aziz Sheikh (UK), Ting Shi (UK), Joshua Vogel (Australia), Rachael Wood (UK), John Wright (UK), Helga Zoega (Australia). Funding Information: The Co-OPT ACS study is funded through a Wellcome Trust Clinical Career Development Fellowship grant (Funding Reference number 209560/Z/17) awarded to Sarah J Stock. The funders had no role in study design, data collection, data analysis, decision to publish, or preparation of the manuscript. The Sponsor of the study is the University of Edinburgh (www.ed.ac. uk), Sponsor reference AC19119. For the purpose of open access, the author has applied a CC BY public copyright licence to any Author Accepted Manuscript version arising from this submission.Peer reviewedPublisher PD

    Search for the standard model Higgs boson in the H to ZZ to 2l 2nu channel in pp collisions at sqrt(s) = 7 TeV

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    A search for the standard model Higgs boson in the H to ZZ to 2l 2nu decay channel, where l = e or mu, in pp collisions at a center-of-mass energy of 7 TeV is presented. The data were collected at the LHC, with the CMS detector, and correspond to an integrated luminosity of 4.6 inverse femtobarns. No significant excess is observed above the background expectation, and upper limits are set on the Higgs boson production cross section. The presence of the standard model Higgs boson with a mass in the 270-440 GeV range is excluded at 95% confidence level.Comment: Submitted to JHE

    The effect of flow speed and food size on the capture efficiency and feeding behaviour of the cold-water coral Lophelia pertusa

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    The capture efficiency and feeding behaviour of the cold-water coral (CWC) Lophelia pertusa (Linnaeus, 1758) were investigated considering: (1) different food types, (2) different food sizes and (3) different current speeds and temperatures. This study used two different multifactorial experimental approaches: (1) Corals were subjected to three different flow speeds (2, 5 and 10 cm s− 1) in 5 l volume tanks, and three different food types (alive zooplankton, alive algae, and dry particulate organic carbon) were offered to the corals under each current regime, analysing the capture rates of the corals under these different flow velocities. (2) In a flume, the feeding behaviour of the coral polyps was studied under different current speed regimes (1, 7, 15 and 27 cm s− 1) and a temperature change over a range of 8–12 °C. The obtained results confirm that low flow speeds (below 7 cm s− 1) appear optimal for a successful prey capture, and temperature did not have an effect on polyp expansion behaviour for L. pertusa. In conclusion, flow speeds clearly impact food capture efficiency in L. pertusa, with zooplankton predominantly captured prey at low flow velocities (2 cm s− 1) and phytoplankton captured at higher flow velocities of 5 cm s− 1. This split in capture efficiency may allow corals to exploit different food sources under different tidal and flow conditionsVersión del editor2,263

    Search for anomalous t t-bar production in the highly-boosted all-hadronic final state

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    A search is presented for a massive particle, generically referred to as a Z', decaying into a t t-bar pair. The search focuses on Z' resonances that are sufficiently massive to produce highly Lorentz-boosted top quarks, which yield collimated decay products that are partially or fully merged into single jets. The analysis uses new methods to analyze jet substructure, providing suppression of the non-top multijet backgrounds. The analysis is based on a data sample of proton-proton collisions at a center-of-mass energy of 7 TeV, corresponding to an integrated luminosity of 5 inverse femtobarns. Upper limits in the range of 1 pb are set on the product of the production cross section and branching fraction for a topcolor Z' modeled for several widths, as well as for a Randall--Sundrum Kaluza--Klein gluon. In addition, the results constrain any enhancement in t t-bar production beyond expectations of the standard model for t t-bar invariant masses larger than 1 TeV.Comment: Submitted to the Journal of High Energy Physics; this version includes a minor typo correction that will be submitted as an erratu

    Search for New Physics with Jets and Missing Transverse Momentum in pp collisions at sqrt(s) = 7 TeV

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    A search for new physics is presented based on an event signature of at least three jets accompanied by large missing transverse momentum, using a data sample corresponding to an integrated luminosity of 36 inverse picobarns collected in proton--proton collisions at sqrt(s)=7 TeV with the CMS detector at the LHC. No excess of events is observed above the expected standard model backgrounds, which are all estimated from the data. Exclusion limits are presented for the constrained minimal supersymmetric extension of the standard model. Cross section limits are also presented using simplified models with new particles decaying to an undetected particle and one or two jets

    Measurement of the t t-bar production cross section in the dilepton channel in pp collisions at sqrt(s) = 7 TeV

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    The t t-bar production cross section (sigma[t t-bar]) is measured in proton-proton collisions at sqrt(s) = 7 TeV in data collected by the CMS experiment, corresponding to an integrated luminosity of 2.3 inverse femtobarns. The measurement is performed in events with two leptons (electrons or muons) in the final state, at least two jets identified as jets originating from b quarks, and the presence of an imbalance in transverse momentum. The measured value of sigma[t t-bar] for a top-quark mass of 172.5 GeV is 161.9 +/- 2.5 (stat.) +5.1/-5.0 (syst.) +/- 3.6(lumi.) pb, consistent with the prediction of the standard model.Comment: Replaced with published version. Included journal reference and DO

    Combined search for the quarks of a sequential fourth generation

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    Results are presented from a search for a fourth generation of quarks produced singly or in pairs in a data set corresponding to an integrated luminosity of 5 inverse femtobarns recorded by the CMS experiment at the LHC in 2011. A novel strategy has been developed for a combined search for quarks of the up and down type in decay channels with at least one isolated muon or electron. Limits on the mass of the fourth-generation quarks and the relevant Cabibbo-Kobayashi-Maskawa matrix elements are derived in the context of a simple extension of the standard model with a sequential fourth generation of fermions. The existence of mass-degenerate fourth-generation quarks with masses below 685 GeV is excluded at 95% confidence level for minimal off-diagonal mixing between the third- and the fourth-generation quarks. With a mass difference of 25 GeV between the quark masses, the obtained limit on the masses of the fourth-generation quarks shifts by about +/- 20 GeV. These results significantly reduce the allowed parameter space for a fourth generation of fermions.Comment: Replaced with published version. Added journal reference and DO
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