121 research outputs found

    Measurement of ϒ production in pp collisions at √s = 2.76 TeV

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    The production of ϒ(1S), ϒ(2S) and ϒ(3S) mesons decaying into the dimuon final state is studied with the LHCb detector using a data sample corresponding to an integrated luminosity of 3.3 pb−1 collected in proton–proton collisions at a centre-of-mass energy of √s = 2.76 TeV. The differential production cross-sections times dimuon branching fractions are measured as functions of the ϒ transverse momentum and rapidity, over the ranges pT < 15 GeV/c and 2.0 < y < 4.5. The total cross-sections in this kinematic region, assuming unpolarised production, are measured to be σ (pp → ϒ(1S)X) × B ϒ(1S)→μ+μ− = 1.111 ± 0.043 ± 0.044 nb, σ (pp → ϒ(2S)X) × B ϒ(2S)→μ+μ− = 0.264 ± 0.023 ± 0.011 nb, σ (pp → ϒ(3S)X) × B ϒ(3S)→μ+μ− = 0.159 ± 0.020 ± 0.007 nb, where the first uncertainty is statistical and the second systematic

    Long-range angular correlations on the near and away side in p–Pb collisions at

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    Study of the doubly charmed tetraquark T+cc

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    Quantum chromodynamics, the theory of the strong force, describes interactions of coloured quarks and gluons and the formation of hadronic matter. Conventional hadronic matter consists of baryons and mesons made of three quarks and quark-antiquark pairs, respectively. Particles with an alternative quark content are known as exotic states. Here a study is reported of an exotic narrow state in the D0D0π+ mass spectrum just below the D*+D0 mass threshold produced in proton-proton collisions collected with the LHCb detector at the Large Hadron Collider. The state is consistent with the ground isoscalar T+cc tetraquark with a quark content of ccu⎯⎯⎯d⎯⎯⎯ and spin-parity quantum numbers JP = 1+. Study of the DD mass spectra disfavours interpretation of the resonance as the isovector state. The decay structure via intermediate off-shell D*+ mesons is consistent with the observed D0π+ mass distribution. To analyse the mass of the resonance and its coupling to the D*D system, a dedicated model is developed under the assumption of an isoscalar axial-vector T+cc state decaying to the D*D channel. Using this model, resonance parameters including the pole position, scattering length, effective range and compositeness are determined to reveal important information about the nature of the T+cc state. In addition, an unexpected dependence of the production rate on track multiplicity is observed

    Reducing the environmental impact of surgery on a global scale: systematic review and co-prioritization with healthcare workers in 132 countries

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    Abstract Background Healthcare cannot achieve net-zero carbon without addressing operating theatres. The aim of this study was to prioritize feasible interventions to reduce the environmental impact of operating theatres. Methods This study adopted a four-phase Delphi consensus co-prioritization methodology. In phase 1, a systematic review of published interventions and global consultation of perioperative healthcare professionals were used to longlist interventions. In phase 2, iterative thematic analysis consolidated comparable interventions into a shortlist. In phase 3, the shortlist was co-prioritized based on patient and clinician views on acceptability, feasibility, and safety. In phase 4, ranked lists of interventions were presented by their relevance to high-income countries and low–middle-income countries. Results In phase 1, 43 interventions were identified, which had low uptake in practice according to 3042 professionals globally. In phase 2, a shortlist of 15 intervention domains was generated. In phase 3, interventions were deemed acceptable for more than 90 per cent of patients except for reducing general anaesthesia (84 per cent) and re-sterilization of ‘single-use’ consumables (86 per cent). In phase 4, the top three shortlisted interventions for high-income countries were: introducing recycling; reducing use of anaesthetic gases; and appropriate clinical waste processing. In phase 4, the top three shortlisted interventions for low–middle-income countries were: introducing reusable surgical devices; reducing use of consumables; and reducing the use of general anaesthesia. Conclusion This is a step toward environmentally sustainable operating environments with actionable interventions applicable to both high– and low–middle–income countries

    Underlying Event measurements in pp collisions at s=0.9 \sqrt {s} = 0.9 and 7 TeV with the ALICE experiment at the LHC

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    Where Brain, Body and World Collide

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    The production cross section of electrons from semileptonic decays of beauty hadrons was measured at mid-rapidity (|y| < 0.8) in the transverse momentum range 1 < pt < 8 Gev/c with the ALICE experiment at the CERN LHC in pp collisions at a center of mass energy sqrt{s} = 7 TeV using an integrated luminosity of 2.2 nb^{-1}. Electrons from beauty hadron decays were selected based on the displacement of the decay vertex from the collision vertex. A perturbative QCD calculation agrees with the measurement within uncertainties. The data were extrapolated to the full phase space to determine the total cross section for the production of beauty quark-antiquark pairs

    Complications related to endoscopic lung volume reduction for emphysema with endobronchial valves: Results of a multicenter study

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    Despite bronchoscopic lung volume reduction (BLVR) with valves is a minimally invasive treatment for emphysema, it can associate with some complications. We aimed at evaluating the rate and type of complications related to valve treatment and their impact on clinical outcomes.Background: Despite bronchoscopic lung volume reduction (BLVR) with valves is a minimally invasive treatment for emphysema, it can associate with some complications. We aimed at evaluating the rate and type of complications related to valve treatment and their impact on clinical outcomes. Methods: It is a retrospective multicenter study including all consecutive patients with severe heterogeneous emphysema undergoing BLVR with endobronchial valve treatment and developed any complications related to this procedure. The type of complication, the time of onset, the treatment required and the out-come were evaluated. Response to treatment was assessed according to the minimal clinically important difference (MCID) as follows: an improvement of ≥15% in forced expiratory volume in one second (FEV1); of −8% in residual volume (RV); of ≥26 m in 6-minnute walking distance (6MWD); and of ≥4 points on the St. George's Respiratory Questionnaire (SGRQ). Target lobe volume reduction (TLVR) ≥350 mL was considered significant. Results: One hundred and seven out of 423 (25.3%) treated patients had complications related to valve treatment including pneumothorax (17.3%); pneumonia (1.7%), chronic obstructive pulmonary disease (COPD) exacerbation (0.9%), respiratory failure (1.4%), valve migration (2.1%), and hemoptysis (1.9%). In all cases complications resolved with appropriate treatment including removal of valves in 21/107 cases (19.6%). Patients with TLVR ≥350 mL (n=64) vs. those <350 mL (n=43) had a statistically significant higher improvement in FEV1 (19.0%±3.9% vs. 3.0%±0.9%; P=0.0003); in RV (−10.0%±4.8% vs. −4.0%±2.9%; P=0.002); in 6MWD (33.0±19.0 vs. 12.0±6.3 metres; P=0.001); and in SGRQ (−15.0±2.9 vs. −8.0±3.5 points; P=0.01). Only patients with TLVR ≥350 mL met or exceeded the MCID cut-off criteria for FEV1 (19.0%±3.9%), RV (−10.0%±4.8%), 6MWT (33.0±19.0 metres), and SGQR (−15.0±2.9 points). Five patients (1.2%) died during follow-up for causes not related to valves treatment neither to any of the complications described. Conclusions: Valve treatment is a safe and reversible procedure. The presence of complications seems not to have a significant impact on clinical outcome in patients with lobar atelectasis. Due to poor clinical conditions and possible complications, BLVR should be performed in high volume centers with a multidisciplinary approach

    DRAMATURGIA-Proyecto ADAE

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    Sitio web del proyecto de investigación "Análisis de la dramaturgia actual en español; Cuba, México, Argentina, España (ADAE1)". consultado el 25/04/2019.La finalidad del Proyecto es estudiar la dramaturgia que se escribe y representa actualmente, o sea, desde hace dos o tres décadas, en el ámbito de la lengua española.Ministerio de Economía y Competitividad (España), proyecto FFI2008-01536Peer reviewe

    Assessment of Olfactory Function in MAPT-Associated Neurodegenerative Disease Reveals Odor-Identification Irreproducibility as a Non-Disease-Specific, General Characteristic of Olfactory Dysfunction

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