816 research outputs found

    Towards the prevention of acute lung injury: a population based cohort study protocol

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>Acute lung injury (ALI) is an example of a critical care syndrome with limited treatment options once the condition is fully established. Despite improved understanding of pathophysiology of ALI, the clinical impact has been limited to improvements in supportive treatment. On the other hand, little has been done on the prevention of ALI. Olmsted County, MN, geographically isolated from other urban areas offers the opportunity to study clinical pathogenesis of ALI in a search for potential prevention targets.</p> <p>Methods/Design</p> <p>In this population-based observational cohort study, the investigators identify patients at high risk of ALI using the prediction model applied within the first six hours of hospital admission. Using a validated system-wide electronic surveillance, Olmsted County patients at risk are followed until ALI, death or hospital discharge. Detailed in-hospital (second hit) exposures and meaningful short and long term outcomes (quality-adjusted survival) are compared between ALI cases and high risk controls matched by age, gender and probability of developing ALI. Time sensitive biospecimens are collected for collaborative research studies. Nested case control comparison of 500 patients who developed ALI with 500 matched controls will provide an adequate power to determine significant differences in common hospital exposures and outcomes between the two groups.</p> <p>Discussion</p> <p>This population-based observational cohort study will identify patients at high risk early in the course of disease, the burden of ALI in the community, and the potential targets for future prevention trials.</p

    Discovery of Pyrazolopyrimidine Derivatives as Novel Dual Inhibitors of BTK and PI3Kδ

    No full text
    The aberrant activation of B-cells has been implicated in several types of cancers and hematological disorders. BTK and PI3Kδ are kinases responsible for B-cell signal transduction, and inhibitors of these enzymes have demonstrated clinical benefit in certain types of lymphoma. Simultaneous inhibition of these pathways could result in more robust responses or overcome resistance as observed in single agent use. We report a series of novel compounds that have low nanomolar potency against both BTK and PI3Kδ as well as acceptable PK properties that could be useful in the development of treatments against B-cell related diseases

    Search for Higgs Boson and Observation of Z Boson through their Decay into a Charm Quark-Antiquark Pair in Boosted Topologies in Proton-Proton Collisions at s\sqrt{s} =13 TeV

    No full text
    A search for the standard model (SM) Higgs boson (H) produced with transverse momentum greater than 450 GeV and decaying to a charm quark-antiquark (ccˉ\mathrm{c\bar{c}}) pair is presented. The search is performed using proton-proton collision data collected at s\sqrt{s} = 13 TeV by the CMS experiment at the LHC, corresponding to an integrated luminosity of 138 fb1^{-1}. Boosted H \toccˉ\mathrm{c\bar{c}} decay products are reconstructed as a single large-radius jet and identified using a deep neural network charm tagging technique. The method is validated by measuring the Z \toccˉ\mathrm{c\bar{c}} decay process, which is observed in association with jets at high pTp_\mathrm{T} for the first time with a signal strength of 1.00 0.14+0.17_{-0.14}^{+0.17} (syst) ±\pm 0.08 (theo) ±\pm 0.06 (stat), defined as the ratio of the observed process rate to the standard model expectation. The observed (expected) upper limit on σ\sigma(H) B\mathcal{B}(H \toccˉ\mathrm{c\bar{c}}) is set at 47 (39) times the SM prediction at 95% confidence level

    Measurement of the angle between jet axes in pp collisions at s \sqrt{s} = 5.02 TeV

    No full text

    Search for pair production of vector-like quarks in leptonic final states in proton-proton collisions at s \sqrt{s} = 13 TeV

    No full text
    A search is presented for vector-like T and B quark-antiquark pairs produced in proton-proton collisions at a center-of-mass energy of 13 TeV. Data were collected by the CMS experiment at the CERN LHC in 2016–2018, with an integrated luminosity of 138 fb1^{−1}. Events are separated into single-lepton, same-sign charge dilepton, and multi-lepton channels. In the analysis of the single-lepton channel a multilayer neural network and jet identification techniques are employed to select signal events, while the same-sign dilepton and multilepton channels rely on the high-energy signature of the signal to distinguish it from standard model backgrounds. The data are consistent with standard model background predictions, and the production of vector-like quark pairs is excluded at 95% confidence level for T quark masses up to 1.54 TeV and B quark masses up to 1.56 TeV, depending on the branching fractions assumed, with maximal sensitivity to decay modes that include multiple top quarks. The limits obtained in this search are the strongest limits to date for TT \textrm{T}\overline{\textrm{T}} production, excluding masses below 1.48 TeV for all decays to third generation quarks, and are the strongest limits to date for BB \textrm{B}\overline{\textrm{B}} production with B quark decays to tW.[graphic not available: see fulltext

    Energy dependence of coherent photonuclear production of J/ψ mesons in ultra-peripheral Pb-Pb collisions at sNN \sqrt{{\textrm{s}}_{\textrm{NN}}} = 5.02 TeV

    No full text
    The cross section for coherent photonuclear production of J/ψ is presented as a function of the electromagnetic dissociation (EMD) of Pb. The measurement is performed with the ALICE detector in ultra-peripheral Pb-Pb collisions at a centre-of-mass energy per nucleon pair of sNN \sqrt{{\textrm{s}}_{\textrm{NN}}} = 5.02 TeV. Cross sections are presented in five different J/ψ rapidity ranges within |y| < 4, with the J/ψ reconstructed via its dilepton decay channels. In some events the J/ψ is not accompanied by EMD, while other events do produce neutrons from EMD at beam rapidities either in one or the other beam direction, or in both. The cross sections in a given rapidity range and for different configurations of neutrons from EMD allow for the extraction of the energy dependence of this process in the range 17 < WγPb,n_{γ Pb,n} < 920 GeV, where WγPb,n_{γ Pb,n} is the centre-of-mass energy per nucleon of the γPb system. This range corresponds to a Bjorken-x interval spanning about three orders of magnitude: 1.1 × 105^{−5} < x < 3.3 × 102^{−2}. In addition to the ultra-peripheral and photonuclear cross sections, the nuclear suppression factor is obtained. These measurements point to a strong depletion of the gluon distribution in Pb nuclei over a broad, previously unexplored, energy range. These results, together with previous ALICE measurements, provide unprecedented information to probe quantum chromodynamics at high energies

    Production of KS0{\rm K}^{0}_{\rm{S}}, Λ\Lambda (Λˉ\bar{\Lambda}), Ξ±\Xi^{\pm} and Ω±\Omega^{\pm} in jets and in the underlying event in pp and p-Pb collisions

    No full text

    Search for top squarks in the four-body decay mode with single lepton final states in proton-proton collisions at s= \sqrt{s}= 13 TeV

    No full text
    A search for the pair production of the lightest supersymmetric partner of the top quark, the top squark (t~1 \tilde{\mathrm{t}}_{1} ), is presented. The search targets the four-body decay of the t~1 \tilde{\mathrm{t}}_{1} , which is preferred when the mass difference between the top squark and the lightest supersymmetric particle is smaller than the mass of the W boson. This decay mode consists of a bottom quark, two other fermions, and the lightest neutralino (χ~10 \tilde{\chi}_{1}^{0} ), which is assumed to be the lightest supersymmetric particle. The data correspond to an integrated luminosity of 138 fb1 ^{-1} of proton-proton collisions at a center-of-mass energy of 13 TeV collected by the CMS experiment at the CERN LHC. Events are selected using the presence of a high-momentum jet, an electron or muon with low transverse momentum, and a significant missing transverse momentum. The signal is selected based on a multivariate approach that is optimized for the difference between m(t~1) m(\tilde{\mathrm{t}}_{1}) and m(χ~10) m(\tilde{\chi}_{1}^{0}) . The contribution from leading background processes is estimated from data. No significant excess is observed above the expectation from standard model processes. The results of this search exclude top squarks at 95% confidence level for masses up to 480 and 700 GeV for m(t~1)m(χ~10)= m(\tilde{\mathrm{t}}_{1}) - m(\tilde{\chi}_{1}^{0}) = 10 and 80 GeV, respectively.A search for the pair production of the lightest supersymmetric partner of the top quark, the top squark (t1 {\overset{\sim }{\textrm{t}}}_1 ), is presented. The search targets the four-body decay of the t1 {\overset{\sim }{\textrm{t}}}_1 , which is preferred when the mass difference between the top squark and the lightest supersymmetric particle is smaller than the mass of the W boson. This decay mode consists of a bottom quark, two other fermions, and the lightest neutralino (χ10 {\overset{\sim }{\chi}}_1^0 ), which is assumed to be the lightest supersymmetric particle. The data correspond to an integrated luminosity of 138 fb1^{−1} of proton-proton collisions at a center-of-mass energy of 13 TeV collected by the CMS experiment at the CERN LHC. Events are selected using the presence of a high-momentum jet, an electron or muon with low transverse momentum, and a significant missing transverse momentum. The signal is selected based on a multivariate approach that is optimized for the difference between m(t1 {\overset{\sim }{\textrm{t}}}_1 ) and m(χ10 {\overset{\sim }{\chi}}_1^0 ). The contribution from leading background processes is estimated from data. No significant excess is observed above the expectation from standard model processes. The results of this search exclude top squarks at 95% confidence level for masses up to 480 and 700 GeV for m(t1 {\overset{\sim }{\textrm{t}}}_1 ) − m(χ10 {\overset{\sim }{\chi}}_1^0 ) = 10 and 80 GeV, respectively.[graphic not available: see fulltext]A search for the pair production of the lightest supersymmetric partner of the top quark, the top squark (t~1\tilde{\mathrm{t}}_1), is presented. The search targets the four-body decay of the t~1\tilde{\mathrm{t}}_1, which is preferred when the mass difference between the top squark and the lightest supersymmetric particle is smaller than the mass of the W boson. This decay mode consists of a bottom quark, two other fermions, and the lightest neutralino (χ~10\tilde{\chi}^0_1), which is assumed to be the lightest supersymmetric particle. The data correspond to an integrated luminosity of 138 fb1^{-1} of proton-proton collisions at a center-of-mass energy of 13 TeV collected by the CMS experiment at the CERN LHC. Events are selected using the presence of a high-momentum jet, an electron or muon with low transverse momentum, and a significant missing transverse momentum. The signal is selected based on a multivariate approach that is optimized for the difference between m(t~1)m(\tilde{\mathrm{t}}_1) and m(χ~10)m(\tilde{\chi}^0_1). The contribution from leading background processes is estimated from data. No significant excess is observed above the expectation from standard model processes. The results of this search exclude top squarks at 95% confidence level for masses up to 480 and 700 GeV for m(t~1)m(χ~10m(\tilde{\mathrm{t}}_1) - m(\tilde{\chi}^0_1) = 10 and 80 GeV, respectively
    corecore