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Sökning: WFRF:(Libby E)

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1.
  • Schael, S., et al. (författare)
  • Electroweak measurements in electron positron collisions at W-boson-pair energies at LEP
  • 2013
  • Ingår i: Physics Reports. - : Elsevier BV. - 0370-1573 .- 1873-6270. ; 532:4, s. 119-244
  • Forskningsöversikt (refereegranskat)abstract
    • Electroweak measurements performed with data taken at the electron positron collider LEP at CERN from 1995 to 2000 are reported. The combined data set considered in this report corresponds to a total luminosity of about 3 fb(-1) collected by the four LEP experiments ALEPH, DELPHI, 13 and OPAL, at centre-of-mass energies ranging from 130 GeV to 209 GeV. Combining the published results of the four LEP experiments, the measurements include total and differential cross-sections in photon-pair, fermion-pair and four-fermion production, the latter resulting from both double-resonant WW and ZZ production as well as singly resonant production. Total and differential cross-sections are measured precisely, providing a stringent test of the Standard Model at centre-of-mass energies never explored before in electron positron collisions. Final-state interaction effects in four-fermion production, such as those arising from colour reconnection and Bose Einstein correlations between the two W decay systems arising in WW production, are searched for and upper limits on the strength of possible effects are obtained. The data are used to determine fundamental properties of the W boson and the electroweak theory. Among others, the mass and width of the W boson, m(w) and Gamma(w), the branching fraction of W decays to hadrons, B(W -> had), and the trilinear gauge-boson self-couplings g(1)(Z), K-gamma and lambda(gamma), are determined to be: m(w) = 80.376 +/- 0.033 GeV Gamma(w) = 2.195 +/- 0.083 GeV B(W -> had) = 67.41 +/- 0.27% g(1)(Z) = 0.984(-0.020)(+0.018) K-gamma - 0.982 +/- 0.042 lambda(gamma) = 0.022 +/- 0.019. (C) 2013 Elsevier B.V. All rights reserved.
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2.
  • Schael, S, et al. (författare)
  • Precision electroweak measurements on the Z resonance
  • 2006
  • Ingår i: Physics Reports. - : Elsevier BV. - 0370-1573 .- 1873-6270. ; 427:5-6, s. 257-454
  • Forskningsöversikt (refereegranskat)abstract
    • We report on the final electroweak measurements performed with data taken at the Z resonance by the experiments operating at the electron-positron colliders SLC and LEP. The data consist of 17 million Z decays accumulated by the ALEPH, DELPHI, L3 and OPAL experiments at LEP, and 600 thousand Z decays by the SLID experiment using a polarised beam at SLC. The measurements include cross-sections, forward-backward asymmetries and polarised asymmetries. The mass and width of the Z boson, m(Z) and Gamma(Z), and its couplings to fermions, for example the p parameter and the effective electroweak mixing angle for leptons, are precisely measured: m(Z) = 91.1875 +/- 0.0021 GeV, Gamma(Z) = 2.4952 +/- 0.0023 GeV, rho(l) = 1.0050 +/- 0.0010, sin(2)theta(eff)(lept) = 0.23153 +/- 0.00016. The number of light neutrino species is determined to be 2.9840 +/- 0.0082, in agreement with the three observed generations of fundamental fermions. The results are compared to the predictions of the Standard Model (SM). At the Z-pole, electroweak radiative corrections beyond the running of the QED and QCD coupling constants are observed with a significance of five standard deviations, and in agreement with the Standard Model. Of the many Z-pole measurements, the forward-backward asymmetry in b-quark production shows the largest difference with respect to its SM expectation, at the level of 2.8 standard deviations. Through radiative corrections evaluated in the framework of the Standard Model, the Z-pole data are also used to predict the mass of the top quark, m(t) = 173(+10)(+13) GeV, and the mass of the W boson, m(W) = 80.363 +/- 0.032 GeV. These indirect constraints are compared to the direct measurements, providing a stringent test of the SM. Using in addition the direct measurements of m(t) and m(W), the mass of the as yet unobserved SM Higgs boson is predicted with a relative uncertainty of about 50% and found to be less than 285 GeV at 95% confidence level. (c) 2006 Elsevier B.V. All rights reserved.
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3.
  • Abreu, P., et al. (författare)
  • Search for sleptons in e+e- collisions at √s = 183 to 189 GeV
  • 2001
  • Ingår i: European Physical Journal C. - : Springer Science and Business Media LLC. - 1434-6044 .- 1434-6052. ; 19:1, s. 29-42
  • Tidskriftsartikel (refereegranskat)abstract
    • Data taken by the DELPHI experiment at centre-of-mass energies of 183 GeV and 189 GeV with a total integrated luminosity of 212 pb-1 have been used to search for the supersymmetric partners of the electrons, muons, and taus in the context of the Minimal Supersymmetric Standard Model (MSSM). The decay topologies searched for were the direct decay (ℓ̃ → ℓx̃), producing acoplanar lepton pairs plus missing energy, and the cascade decay (ℓ → ℓx̃0 2 → ℓγx̃0 1), producing acoplanar lepton and photon pairs plus missing energy. The observed number of events is in agreement with Standard Model predictions. The 95% CL excluded mass limits for selectrons, smuons and staus are mẽ ≤ 87 GeV/c2, mμ̃ ≤ 80 GeV/c2 and mτ̃ 75 GeV/c2, respectively, for values of μ=-200 GeV/c2 and tanβ=1.5.
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4.
  • Abreu, P., et al. (författare)
  • Measurement of the gluon fragmentation function and a comparison of the scaling violation in gluon and quark jets
  • 2000
  • Ingår i: European Physical Journal C. - : Springer Science and Business Media LLC. - 1434-6044 .- 1434-6052. ; 13:4, s. 573-589
  • Tidskriftsartikel (refereegranskat)abstract
    • The fragmentation functions of quarks and gluons are measured in various three-jet topologies in Z decays from the full data set collected with the DELPHI detector at the Z resonance between 1992 and 995. The results at different values of transverse momentum-like scales are compared. A parameterization of the quark and gluon fragmentation functions at a fixed reference scale is given. The quark and gluon fragmentation functions show the predicted pattern of scaling violations. The scaling violation for quark jets as a function of a transverse momentum-like scale is in a good agreement with that observed in lower energy e+e- annihilation experiments. For gluon jets it appears to be significantly stronger. The scale dependences of the gluon and quark fragmentation functions agree with the prediction of the DGLAP evolution equations from which the colour factor ratio CA/CF is measured to be: CA/CF = 2.26 ± 0.09stat. ± 0.06sys. ± 0.12clus.,scale..
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5.
  • Abreu, P., et al. (författare)
  • Study of dimuon production in photon-photon collisions and measurement of QED photon structure functions at LEP
  • 2001
  • Ingår i: European Physical Journal C. - : Springer Science and Business Media LLC. - 1434-6044 .- 1434-6052. ; 19:1, s. 15-28
  • Tidskriftsartikel (refereegranskat)abstract
    • Muon pair production in the process e+e- → e+e- μ+μ- is studied using the data taken at LEP1 (√s ≃ mz) with the DELPHI detector during the years 1992-1995. The corresponding integrated luminosity is 138.5 pb-1. The QED predictions have been tested over the whole Q2 range accessible at LEP1 (from several GeV2/c4 to several hundred GeV2/c4) by comparing experimental distributions with distributions resulting from Monte Carlo simulations using various generators. Selected events are used to extract the leptonic photon structure function Fγ 2. Azimuthal correlations are used to obtain information on additional structure functions, Fγ A and Fγ B, which originate from interference terms of the scattering amplitudes. The measured ratios Fγ A/Fγ 2 and FγB/Fγ 2 are significantly different from zero and consistent with QED predictions.
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6.
  • Abdallah, J., et al. (författare)
  • Measurements of CP-conserving trilinear gauge boson couplings WWV (V gamma, Z) in e(+)e(-) collisions at LEP2
  • 2010
  • Ingår i: European Physical Journal C. - : Springer Science and Business Media LLC. - 1434-6044 .- 1434-6052. ; 66:1-2, s. 35-56
  • Tidskriftsartikel (refereegranskat)abstract
    • The data taken by DELPHI at centre-of-mass energies between 189 and 209 GeV are used to place limits on the CP-conserving trilinear gauge boson couplings Delta g(1)(Z), lambda(gamma) and Delta k(gamma) associated to W+W- and single W production at LEP2. Using data from the jjl nu, jjjj, jjX and lX final states, where j,l and X represent a jet, a lepton and missing four-momentum, respectively, the following limits are set on the couplings when one parameter is allowed to vary and the others are set to their Standard Model values of zero: Delta g(1)(Z) =-0.025-(+0.033)(0.030,), lambda(gamma) = 0.002(-0.035)(+0.035) and Delta k(gamma) = 0.024(-0.081)(+0.077). Results are also presented when two or three parameters are allowed to vary. All observations are consistent with the predictions of the Standard Model and supersede the previous results on these gauge coupling parameters published by DELPHI.
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7.
  • Adcox, K, et al. (författare)
  • PHENIX detector overview
  • 2003
  • Ingår i: Nuclear Instruments & Methods in Physics Research. Section A: Accelerators, Spectrometers, Detectors, and Associated Equipment. - 0167-5087. ; 499:2-3, s. 469-479
  • Tidskriftsartikel (refereegranskat)abstract
    • The PHENIX detector is designed to perform a broad study of A-A, p-A, and p-p collisions to investigate nuclear matter under extreme conditions. A wide variety of probes, sensitive to all timescales, are used to study systematic variations with species and energy as well as to measure the spin structure of the nucleon. Designing for the needs of the heavy-ion and polarized-proton programs has produced a detector with unparalleled capabilities. PHENIX measures electron and muon pairs, photons, and hadrons with excellent energy and momentum resolution. The detector consists of a large number of subsystems that are discussed in other papers in this volume. The overall design parameters of the detector are presented. (C) 2002 Elsevier Science B.V. All rights reserved.
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8.
  • Ablikim, M., et al. (författare)
  • Search for the rare decays D -> h(h((')))e(+) e(-)
  • 2018
  • Ingår i: Physical Review D. - : AMER PHYSICAL SOC. - 2470-0010 .- 2470-0029. ; 97:7
  • Tidskriftsartikel (refereegranskat)abstract
    • We search for rare decays of D mesons to hadrons accompanied by an electron-positron pair (h(h((')))e(+)e(- )),using an e(+)e(-) collision sample corresponding to an integrated luminosity of 2.93 fb(-1) collected with the BESIII detector at root s = 3.773 GeV. No significant signals are observed, and the corresponding upper limits on the branching fractions at the 90% confidence level are determined. The sensitivities of the results are at the level of 10(-5)-10(-6), providing a large improvement over previous searches.
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9.
  • Ablikim, M., et al. (författare)
  • First measurement of e(+)e(-) -> pK(S)(0)(n)over-barK(-) + c.c. above open charm threshold
  • 2018
  • Ingår i: Physical Review D. - 2470-0010 .- 2470-0029. ; 98:3
  • Tidskriftsartikel (refereegranskat)abstract
    • The process e(+)e(-) -> pK(S)(0)(n) over barK(-) + c.c. and its intermediate processes are studied for the first time, using data samples collected with the BESIII detector at BEPCII at center-of-mass energies of 3.773, 4.008, 4.226, 4.258, 4.358, 4.416, and 4.600 GeV, with a total integrated luminosity of 7.4 fb(-1). The Born cross section of e(+)e(-) -> pK(S)(0)(n) over barK(-) + c.c. is measured at each center-of-mass energy, but no significant resonant structure in the measured cross-section line shape between 3.773 and 4.600 GeV is observed. No evident structure is detected in the pK(-), nK(S)(0), pK(S)(0), nK(+), p (n) over bar, or (KSK-)-K-0 invariant mass distributions except for Lambda(1520). The Born cross sections of e(+)e(-) -> Lambda(1520)(n) over barK(S)(0) + c.c. and e(+)e(-) -> Lambda(1520)(p) over barK(+) + c.c. are measured, and the 90% confidence level upper limits on the Born cross sections of e(+)e(-) -> Lambda(1520)(Lambda) over bar (1520) are determined at the seven center-of-mass energies. There is an evident difference in line shape and magnitude of the measured cross sections between e(+)e(-) -> Lambda(1520)(-> pK(-))(n) over barK(S)(0) and e(+)e(-) -> pK-(Lambda) over bar (1520)(-> (n) over barK(S)(0)).
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10.
  • Ablikim, M., et al. (författare)
  • Improved measurements of X-cJ -> Sigma(+) (Sigma)over-bar(-) and Sigma(0)(Sigma)over-bar(0) decays
  • 2018
  • Ingår i: Physical Review D. - : American Physical Society. - 2470-0010 .- 2470-0029. ; 97:5
  • Tidskriftsartikel (refereegranskat)abstract
    • Using a data sample of (448.1 +/- 2.9) x 10(6) psi (3686) events collected with the BESIII detector at the BEPCII collider, we present measurements of branching fractions for the decays X-cJ -> Sigma(+) (Sigma) over bar (-) and Sigma(0) (Sigma) over bar (0) The decays X-c1.2 -> Sigma(+) (Sigma) over bar (-) and Sigma (Sigma) over bar (0) are observed for the first time, and the branching fractions for X-c0 -> Sigma(+) (Sigma) over bar (-) and Sigma(0) (Sigma) over bar (0) decays are measured with improved precision. The branching fraction ratios between the charged and neutral modes are consistent with the prediction of isospin symmetry.
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11.
  • Ablikim, M., et al. (författare)
  • Measurement of branching fractions for psi(3686) -> gamma eta ', gamma eta, and gamma pi(0)
  • 2017
  • Ingår i: Physical Review D. - : AMER PHYSICAL SOC. - 2470-0010 .- 2470-0029. ; 96:5
  • Tidskriftsartikel (refereegranskat)abstract
    • Using a data sample of 448 x 10(6) psi(3686) events collected with the BESIII detector operating at the BEPCII storage ring, the decays psi(3686) -> gamma eta and psi(3686) -> gamma pi(0) are observed with a statistical significance of 7.3 sigma and 6.7 sigma, respectively. The branching fractions are measured to be B(psi(3686) -> gamma eta) = (0.85 +/- 0.18 +/- 0.05) x 10(-6) and B(psi(3686) ->gamma pi(0)) = (0.95 +/- 0.16 +/- 0.05) x 10(-6). In addition, we measure the branching fraction of psi(3686) -> gamma eta' to be B(psi(3686) -> gamma eta') = (125.1 +/- 2.2 +/- 6.2)x10(-6), which represents an improvement of precision over previous results.
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12.
  • Ablikim, M., et al. (författare)
  • Measurement of e(+)e(-) -> D(D)over-bar cross sections at the psi(3770) resonance
  • 2018
  • Ingår i: Chinese Physics C. - : IOP PUBLISHING LTD. - 1674-1137 .- 2058-6132. ; 42:8
  • Tidskriftsartikel (refereegranskat)abstract
    • We report new measurements of the cross sections for the production of D (D) over bar final states at the psi(3770) resonance. Our data sample consists of an integrated luminosity of 2.93 fb(-1) of e(+)e(-) annihilation data produced by the BEPCII collider and collected and analyzed with the BESIII detector. We exclusively reconstruct three D-0 and six D+ hadronic decay modes and use the ratio of the yield of fully reconstructed D (D) over bar events ("double tags") to the yield of all reconstructed D or (D) over bar mesons ("single tags") to determine the number of D-0(D) over bar (0) and D+D- events, benefiting from the cancellation of many systematic uncertainties. Combining these yields with an independent determination of the integrated luminosity of the data sample, we find the cross sections to be sigma(e(+)e(-) -> D-0(D) over bar (0)(-) )=(3.615 +/- 0.010 +/- 0.038) nb and sigma(e(+)e(-) -> D+D-)=(2.830 +/- 0.011 +/- 0.026) nb, where the uncertainties are statistical and systematic, respectively.
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13.
  • Ablikim, M., et al. (författare)
  • Measurement of the integrated Luminosities of cross-section scan data samples around the psi(3770) mass region
  • 2018
  • Ingår i: Chinese Physics C. - : SCIENCE PRESS. - 1674-1137 .- 2058-6132. ; 42:6
  • Tidskriftsartikel (refereegranskat)abstract
    • To investigate the nature of the psi(3770) resonance and to measure the cross section for e(+)e(-) -> D (D) over bar, a cross-section scan data sample, distributed among 41 center-of-mass energy points from 3.73 to 3.89 GeV, was taken with the BESIII detector operated at the BEPCII collider in the year 2010. By analyzing the large angle Bhabha scattering events, we measure the integrated luminosity of the data sample at each center-of-mass energy point. The total integrated luminosity of the data sample is 76.16 +/- 0.04 +/- 0.61 pb(-1), where the first uncertainty is statistical and the second systematic.
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14.
  • Ablikim, M., et al. (författare)
  • Measurements of absolute branching fractions for Lambda(+)(c) -> Xi K-0(+) and Xi(1530)K-0(+)
  • 2018
  • Ingår i: Physics Letters B. - : ELSEVIER SCIENCE BV. - 0370-2693 .- 1873-2445. ; 783, s. 200-206
  • Tidskriftsartikel (refereegranskat)abstract
    • We report the first measurements of absolute branching fractions for the W-exchange-only processes Lambda(+)(c) -> Xi K-0(+) and Lambda(+)(c)-> Xi(1530)K-0(+) with the double-tag technique, by analyzing an e(+)e(-) collision data sample, that corresponds to an integrated luminosity of 567 pb(-1) collected at a center-of-mass energy of 4.6 GeV by the BESIII detector. The branching fractions are measured to be B(Lambda(+)(c)-> Xi K-0(+)) = (5.90 +/- 0.86 +/- 0.39) x 10(-3) and B(Lambda(+)(c)-> Xi(1530)K-0(+)) = (5.02 +/- 0.99 +/- 0.31) x 10(-3), where the first uncertainties are statistical and the second systematic. Our results are more precise than the previous relative measurements.
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15.
  • Ablikim, M., et al. (författare)
  • Observation of psi(3686) -> eta ' e(+)e(-)
  • 2018
  • Ingår i: Physics Letters B. - : ELSEVIER SCIENCE BV. - 0370-2693 .- 1873-2445. ; 783, s. 452-458
  • Tidskriftsartikel (refereegranskat)abstract
    • Using a data sample of 448.1 x 10(6) psi(3686) events collected with the BESIII detector at the BEPCII collider, we report the first observation of the electromagnetic Dalitz decay psi(3686) -> eta'e(+)e(-), with significances of 7.0 sigma and 6.3 sigma when reconstructing the eta' meson via its decay modes eta' -> gamma pi(+)pi(-) and eta' -> pi(+)pi(-) eta (eta -> gamma gamma), respectively. The weighted average branching fraction is determined to be B(psi(3686) -> eta'e(+)e(-)) = (1.90 +/- 0.25 +/- 0.11) x 10(-6), where the first uncertainty is statistical and the second systematic.
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16.
  • Ablikim, M., et al. (författare)
  • Precision Measurement of the e(+)e(-) -> Lambda(+)(c)(Lambda)over-bar(c)(-) Cross Section Near Threshold
  • 2018
  • Ingår i: Physical Review Letters. - : American Physical Society. - 0031-9007 .- 1079-7114. ; 120:13
  • Tidskriftsartikel (refereegranskat)abstract
    • The cross section of the e(+)e(-) -> Lambda(+)(c)(Lambda) over bar (-)(c) process is measured with unprecedented precision using data collected with the BESIII detector at root s = 4574.5, 4580.0, 4590.0 and 4599.5 MeV. The nonzero cross section near the Lambda(+)(c)(Lambda) over bar (-)(c) production threshold is cleared. At center-of-mass energies root s = 4574.5 and 4599.5 MeV, the higher statistics data enable us to measure the Lambda(c) polar angle distributions. From these, the.c electric over magnetic form-factor ratios (vertical bar G(E)/G(M)vertical bar) are measured for the first time. They are found to be 1.14 +/- 0.14 +/- 0.07 and 1.23 +/- 0.05 +/- 0.03, respectively, where the first uncertainties are statistical and the second are systematic.
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17.
  • Ablikim, M., et al. (författare)
  • Search for invisible decays of omega and phi with J/psi data at BESIII
  • 2018
  • Ingår i: Physical Review D. - : American Physical Society. - 2470-0010 .- 2470-0029. ; 98:3
  • Tidskriftsartikel (refereegranskat)abstract
    • Using a data sample of (1310.6 +/- 7.0) x 10(6) J/psi events collected with the BESIII detector operating at the BEPCII collider, we perform the first experimental search for invisible decays of a light vector meson (V = omega, phi) via J/psi -> V-eta decays. The decay of eta -> pi(+)pi(-)pi(0) is utilized to tag the V meson decaying into the invisible final state. No evidence for a significant invisible signal is observed, and the upper limits on the ratio of branching fractions at the 90% confidence level are determined to be B(omega -> invisible)/B(omega -> pi(+)pi(-)pi(0)) < 8.1 x 10(-5) and B(phi -> invisible)/B(phi -> K+K-) < 3.4 x 10(-4). By using the world average values of B(omega -> pi(+)pi(-)pi(0) and B(phi -> K+K-,) the upper limits on the decay branching fractions at the 90% confidence level are set as B(omega -> invisible) < 7.3 x 10(-5) and B(phi -> invisible) < 1.7 x 10(-4), respectively.
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18.
  • Ablikim, M., et al. (författare)
  • Search for the rare decay of ψ(3686)→Λ+c¯pe+e−+c.c. at BESIII
  • 2018
  • Ingår i: Physical Review D. - 2470-0010 .- 2470-0029. ; 97:9
  • Tidskriftsartikel (refereegranskat)abstract
    • Based on a data sample of (448.1 +/- 2.9) x 10(6)Psi(3686) decays collected with the BESIII experiment, a search for the flavor changing neutral current transition Psi(3686) -> Lambda(+)(c) pe(+) e(-) + c.c. is performed for the first time. No signal candidates are observed and the upper limit on the branching fraction of Psi(3686) -> Lambda(+)(c) pe(+) e(-) is determined to be 1.7 x 10(-6) at the 90% confidence level. The result is consistent with expectations from the standard model, and no evidence for new physics is found.
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19.
  • Ablikim, M., et al. (författare)
  • Observation of the Semileptonic Decay D-0 -> a(0)(980)(-)e(+)nu(e) and Evidence for D+ -> a(0)(980)(0)e(+)nu(e)
  • 2018
  • Ingår i: Physical Review Letters. - : AMER PHYSICAL SOC. - 0031-9007 .- 1079-7114. ; 121:8
  • Tidskriftsartikel (refereegranskat)abstract
    • Using an e(+)e(-) collision data sample of 2.93 fb(-1) collected at a center-of-mass energy of 3.773 GeV by the BESIII detector at BEPCII, we report the observation of D-0 -> a(0)(980)(-)e(+)nu(e) and evidence for D+ -> a(0)(980)(0)e(+)nu(e) with significances of 6.4 sigma and 2.9 sigma, respectively. The absolute branching fractions are determined to be B(D-0 -> a(0)(980)(-)e(+)nu(e)) x B(a(0)(980)(-) -> eta pi(-)) = [1.33(-0.29)(+0.33)(stat) +/- 0.09(syst)] x 10(-4) and B(D+ -> a(0)(980)(0)e(+)nu(e)) x B(a(0)(980)(0) -> eta pi(0)) = [1.66(-0.66)(+0.81)(stat) +/- 0.11(syst) x 10(-4). This is the first time the a(0)(980) meson has been measured in a D-0 semileptonic decay, which would open one more interesting page in the investigation of the nature of the puzzling a(0)(980) states.
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22.
  • Feng, Shaohong, et al. (författare)
  • Dense sampling of bird diversity increases power of comparative genomics
  • 2020
  • Ingår i: Nature. - : Springer Science and Business Media LLC. - 0028-0836 .- 1476-4687. ; 587:7833
  • Tidskriftsartikel (refereegranskat)abstract
    • Whole-genome sequencing projects are increasingly populating the tree of life and characterizing biodiversity(1-4). Sparse taxon sampling has previously been proposed to confound phylogenetic inference(5), and captures only a fraction of the genomic diversity. Here we report a substantial step towards the dense representation of avian phylogenetic and molecular diversity, by analysing 363 genomes from 92.4% of bird families-including 267 newly sequenced genomes produced for phase II of the Bird 10,000 Genomes (B10K) Project. We use this comparative genome dataset in combination with a pipeline that leverages a reference-free whole-genome alignment to identify orthologous regions in greater numbers than has previously been possible and to recognize genomic novelties in particular bird lineages. The densely sampled alignment provides a single-base-pair map of selection, has more than doubled the fraction of bases that are confidently predicted to be under conservation and reveals extensive patterns of weak selection in predominantly non-coding DNA. Our results demonstrate that increasing the diversity of genomes used in comparative studies can reveal more shared and lineage-specific variation, and improve the investigation of genomic characteristics. We anticipate that this genomic resource will offer new perspectives on evolutionary processes in cross-species comparative analyses and assist in efforts to conserve species. A dataset of the genomes of 363 species from the Bird 10,000 Genomes Project shows increased power to detect shared and lineage-specific variation, demonstrating the importance of phylogenetically diverse taxon sampling in whole-genome sequencing.
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23.
  • Hoban, Sean, et al. (författare)
  • Genetic diversity targets and indicators in the CBD post-2020 Global Biodiversity Framework must be improved
  • 2020
  • Ingår i: Biological Conservation. - : Elsevier BV. - 0006-3207 .- 1873-2917. ; 248
  • Tidskriftsartikel (refereegranskat)abstract
    • The 196 parties to the Convention on Biological Diversity (CBD) will soon agree to a post-2020 global framework for conserving the three elements of biodiversity (genetic, species, and ecosystem diversity) while ensuring sustainable development and benefit sharing. As the most significant global conservation policy mechanism, the new CBD framework has far-reaching consequences- it will guide conservation actions and reporting for each member country until 2050. In previous CBD strategies, as well as other major conservation policy mechanisms, targets and indicators for genetic diversity (variation at the DNA level within species, which facilitates species adaptation and ecosystem function) were undeveloped and focused on species of agricultural relevance. We assert that, to meet global conservation goals, genetic diversity within all species, not just domesticated species and their wild relatives, must be conserved and monitored using appropriate metrics. Building on suggestions in a recent Letter in Science (Laikre et al., 2020) we expand argumentation for three new, pragmatic genetic indicators and modifications to two current indicators for maintaining genetic diversity and adaptive capacity of all species, and provide guidance on their practical use. The indicators are: 1) the number of populations with effective population size above versus below 500, 2) the proportion of populations maintained within species, 3) the number of species and populations in which genetic diversity is monitored using DNA-based methods. We also present and discuss Goals and Action Targets for post-2020 biodiversity conservation which are connected to these indicators and underlying data. These pragmatic indicators and goals have utility beyond the CBD; they should benefit conservation and monitoring of genetic diversity via national and global policy for decades to come.
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24.
  • Jaiswal, Siddhartha, et al. (författare)
  • Clonal Hematopoiesis and risk of atherosclerotic cardiovascular disease
  • 2017
  • Ingår i: New England Journal of Medicine. - 0028-4793. ; 377:2, s. 111-121
  • Tidskriftsartikel (refereegranskat)abstract
    • BACKGROUND Clonal hematopoiesis of indeterminate potential (CHIP), which is defined as the presence of an expanded somatic blood-cell clone in persons without other hematologic abnormalities, is common among older persons and is associated with an increased risk of hematologic cancer. We previously found preliminary evidence for an association between CHIP and atherosclerotic cardiovascular disease, but the nature of this association was unclear. METHODS We used whole-exome sequencing to detect the presence of CHIP in peripheral-blood cells and associated such presence with coronary heart disease using samples from four case-control studies that together enrolled 4726 participants with coronary heart disease and 3529 controls. To assess causality, we perturbed the function of Tet2, the second most commonly mutated gene linked to clonal hematopoiesis, in the hematopoietic cells of atherosclerosis-prone mice. RESULTS In nested case-control analyses from two prospective cohorts, carriers of CHIP had a risk of coronary heart disease that was 1.9 times as great as in noncarriers (95% confidence interval [CI], 1.4 to 2.7). In two retrospective case-control cohorts for the evaluation of early-onset myocardial infarction, participants with CHIP had a risk of myocardial infarction that was 4.0 times as great as in noncarriers (95% CI, 2.4 to 6.7). Mutations in DNMT3A, TET2, ASXL1, and JAK2 were each individually associated with coronary heart disease. CHIP carriers with these mutations also had increased coronary-artery calcification, a marker of coronary atherosclerosis burden. Hypercholesterolemia-prone mice that were engrafted with bone marrow obtained from homozygous or heterozygous Tet2 knockout mice had larger atherosclerotic lesions in the aortic root and aorta than did mice that had received control bone marrow. Analyses of macrophages from Tet2 knockout mice showed elevated expression of several chemokine and cytokine genes that contribute to atherosclerosis. CONCLUSIONS The presence of CHIP in peripheral-blood cells was associated with nearly a doubling in the risk of coronary heart disease in humans and with accelerated atherosclerosis in mice. (Funded by the National Institutes of Health and others.)
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29.
  • Adcox, K, et al. (författare)
  • PHENIX central arm tracking detectors
  • 2003
  • Ingår i: Nuclear Instruments & Methods in Physics Research. Section A: Accelerators, Spectrometers, Detectors, and Associated Equipment. - 0167-5087. ; 499:2-3, s. 489-507
  • Tidskriftsartikel (refereegranskat)abstract
    • The PHENIX tracking system consists of Drift Chambers (DC), Pad Chambers (PC) and the Time Expansion Chamber (TEC). PC1/DC and PC2/TEC/PC3 form the inner and outer tracking units, respectively. These units link the track segments that transverse the RICH and extend to the EMCal. The DC measures charged particle trajectories in the r-phi direction to determine P-T of the particles and the invariant mass of particle pairs. The PCs perform 3D spatial point measurements for pattern recognition and longitudinal momentum reconstruction and provide spatial resolution of a few mm in both r-phi and z. The TEC tracks particles passing through the region between the RICH and the EMCal. The design and operational parameters of the detectors are presented and running experience during the first year of data taking with PHENIX is discussed. The observed spatial and momentum resolution is given which imposes a limitation on the identification and characterization of charged particles in various momentum ranges. (C) 2002 Published by Elsevier Science B.V.
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30.
  • Amano, Tatsuya, et al. (författare)
  • Transforming Practice : Checklists for Delivering Change
  • 2022
  • Ingår i: Transforming Conservation : A Practical Guide to Evidence and Decision Making - A Practical Guide to Evidence and Decision Making. - 9781800648562 - 9781800648586 ; , s. 367-386
  • Bokkapitel (refereegranskat)abstract
    • Delivering a revolution in evidence use requires a cultural change across society. For a wide range of groups (practitioners, knowledge brokers, organisations, organisational leaders, policy makers, funders, researchers, journal publishers, the wider conservation community, educators, writers, and journalists), options are described to facilitate a change in practice, and a series of downloadable checklists is provided.
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32.
  • Commins, Scott P, et al. (författare)
  • Galactose-α-1,3-galactose-specific IgE is associated with anaphylaxis but not asthma.
  • 2012
  • Ingår i: American journal of respiratory and critical care medicine. - 1535-4970 .- 1073-449X. ; 185:7, s. 723-30
  • Tidskriftsartikel (refereegranskat)abstract
    • IgE antibodies to the mammalian oligosaccharide galactose-α-1,3-galactose (α-gal) are common in the southeastern United States. These antibodies, which are induced by ectoparasitic ticks, can give rise to positive skin tests or serum assays with cat extract.
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33.
  • Commins, Scott P., et al. (författare)
  • The relevance of tick bites to the production of IgE antibodies to the mammalian oligosaccharide galactose-alpha-1,3-galactose
  • 2011
  • Ingår i: Journal of Allergy and Clinical Immunology. - : Elsevier BV. - 0091-6749 .- 1097-6825. ; 127:5, s. 1286-1293.e6
  • Tidskriftsartikel (refereegranskat)abstract
    • Background: In 2009, we reported a novel form of delayed anaphylaxis to red meat that is related to serum IgE antibodies to the oligosaccharide galactose-alpha-1,3-galactose (alpha-gal). Most of these patients had tolerated meat for many years previously. The implication is that some exposure in adult life had stimulated the production of these IgE antibodies. Objectives: We sought to investigate possible causes of this IgE antibody response, focusing on evidence related to tick bites, which are common in the region where these reactions occur.Methods: Serum assays were carried out with biotinylated proteins and extracts bound to a streptavidin ImmunoCAP.Results: Prospective studies on IgE antibodies in 3 subjects after tick bites showed an increase in levels of IgE to alpha-gal of 20fold or greater. Other evidence included (1) a strong correlation between histories of tick bites and levels of IgE to alpha-gal (chi(2) = 26.8, P < .001), (2) evidence that these IgE antibodies are common in areas where the tick Amblyomma americanum is common, and (3) a significant correlation between IgE antibodies to alpha-gal and IgE antibodies to proteins derived from A americanum (r(s) = 0.75, P < .001).Conclusion: The results presented here provide evidence that tick bites are a cause, possibly the only cause, of IgE specific for alpha-gal in this area of the United States. Both the number of subjects becoming sensitized and the titer of IgE antibodies to alpha-gal are striking. Here we report the first example of a response to an ectoparasite giving rise to an important form of food allergy.
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36.
  • Estrela, Sylvie, et al. (författare)
  • Environmentally Mediated Social Dilemmas
  • 2019
  • Ingår i: Trends in Ecology & Evolution. - : Elsevier. - 0169-5347 .- 1872-8383. ; 34:1, s. 6-18
  • Forskningsöversikt (refereegranskat)abstract
    • By consuming and producing environmental resources, organisms inevitably change their habitats. The consequences of such environmental modifications can be detrimental or beneficial not only to the focal organism but also to other organisms sharing the same environment. Social evolution theory has been very influential in studying how social interactions mediated by public 'goods' or 'bads' evolve by emphasizing the role of spatial structure. The environmental dimensions driving these interactions, however, are typically abstracted away. We propose here a new, environment-mediated taxonomy of social behaviors where organisms are categorized by their production or consumption of environmental factors that can help or harm others in the environment. We discuss microbial examples of our classification and highlight the importance of environmental intermediates more generally.
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37.
  • Fraley, Alexander E, et al. (författare)
  • Relationship of Oxidized Phospholipids and Biomarkers of Oxidized Low- Density Lipoprotein With Cardiovascular Risk Factors, Inflammatory Biomarkers, and Effect of Statin Therapy in Patients With Acute Coronary Syndromes Results From the MIRACL (Myocardial Ischemia Reduction With Aggressive Cholesterol Lowering) Trial
  • 2009
  • Ingår i: JOURNAL OF THE AMERICAN COLLEGE OF CARDIOLOGY. - : Elsevier BV. - 0735-1097. ; 53:23, s. 2186-2196
  • Tidskriftsartikel (refereegranskat)abstract
    • Objectives This study sought to define the relationship between oxidative biomarkers, cardiovascular disease (CVD) risk factors, and inflammatory and thrombosis biomarkers. Background Elevated levels of oxidized phospholipids (OxPL) on apolipoprotein B particles (apoB) represent a novel biomarker of CVD. Previous studies suggest that an increase in OxPL/apoB reflects a positive response to statins and a low-fat diet. Methods This study measured OxPL/apoB, lipoprotein (a) [Lp(a)], and oxidized low-density lipoprotein (OxLDL) biomarkers, consisting of immunoglobulin (Ig) G and IgM autoantibodies to malondialdehyde (MDA)-low-density lipoprotein (LDL) and IgG and IgM apoB-100 immune complexes (IC/apoB), at baseline and after 16 weeks of treatment with atorvastatin 80 mg/day or placebo in 2,342 patients with acute coronary syndromes (ACS) enrolled in the MIRACL (Myocardial Ischemia Reduction With Aggressive Cholesterol Lowering) trial. Results At baseline, potentially atheroprotective IgM autoantibodies and IgM IC/apoB were lower in male patients, diabetic patients, and patients andgt;65 years of age. Patients with an LDL level greater than the median (122 mg/dl) had higher levels of OxPL/apoB, Lp(a), and OxLDL biomarkers compared with those who had an LDL level less than the median. Atorvastatin resulted in significantly larger changes in all biomarkers in female patients, patients age andlt;65 years, patients with LDL cholesterol andlt;122 mg/dl, nonsmokers, and nondiabetic patients (p andlt; 0.0001 for all). In particular, a significant increase in OxPL/apoB in response to atorvastatin was noted in all 20 subgroups evaluated. Weak or no significant correlations were noted between all OxLDL biomarkers and C-reactive protein, serum amyloid A, tissue plasminogen activator, interleukin-6, intercellular adhesion molecule, vascular cell adhesion molecule, P-selectin, and E-selectin at randomization and 16 weeks. Conclusions In patients with ACS, baseline levels of oxidative biomarkers varied according to specific CVD risk factors and were largely independent of inflammatory biomarkers. Atorvastatin uniformly increased OxPL/apoB levels in all subgroups studied. Future studies are warranted to assess whether the increase in OxPL/apoB levels reflects the benefit of effective therapeutic interventions and prediction of new CVD events.
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38.
  • Gallino, A, et al. (författare)
  • Non-coronary atherosclerosis
  • 2014
  • Ingår i: European heart journal. - : Oxford University Press (OUP). - 1522-9645 .- 0195-668X. ; 35:17, s. 1112-
  • Tidskriftsartikel (refereegranskat)
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39.
  • Lannin, Natasha A., et al. (författare)
  • Public perspectives on acquired brain injury rehabilitation and components of care : A Citizens’ Jury
  • 2021
  • Ingår i: Health Expectations. - : John Wiley & Sons. - 1369-6513 .- 1369-7625. ; 24:2, s. 352-362
  • Tidskriftsartikel (refereegranskat)abstract
    • Background: Brain injury rehabilitation is an expensive and long-term endeavour. Very little published information or debate has underpinned policy for service delivery in Australia. Within the context of finite health budgets and the challenges associated with providing optimal care to persons with brain injuries, members of the public were asked ‘What considerations are important to include in a model of care of brain injury rehabilitation?’.Methods: Qualitative study using the Citizen Jury method of participatory research. Twelve adult jurors from the community and seven witnesses participated including a health services funding model expert, peak body representative with lived experience of brain injury, carer of a person with a brain injury, and brain injury rehabilitation specialists. Witnesses were cross-examined by jurors over two days.Results: Key themes related to the need for a model of rehabilitation to: be consumer-focused and supporting the retention of hope; be long-term; provide equitable access to services irrespective of funding source; be inclusive of family; provide advocacy; raise public awareness; and be delivered by experts in a suitable environment. A set of eight recommendations were made.Conclusion: Instigating the recommendations made requires careful consideration of the need for new models of care with flexible services; family involvement; recruitment and retention of highly skilled staff; and providing consumer-focused services that prepare individuals and their carers for the long term.Patient and public contribution: As jury members, the public deliberated information provided by expert witnesses (including a person with a head injury) and wrote the key recommendations.
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40.
  • Schuermans, Art, et al. (författare)
  • Clonal haematopoiesis of indeterminate potential predicts incident cardiac arrhythmias
  • 2024
  • Ingår i: European Heart Journal. - 0195-668X. ; 45:10, s. 791-805
  • Tidskriftsartikel (refereegranskat)abstract
    • Background and Clonal haematopoiesis of indeterminate potential (CHIP), the age-related expansion of blood cells with preleukemic mutaAims tions, is associated with atherosclerotic cardiovascular disease and heart failure. This study aimed to test the association of CHIP with new-onset arrhythmias.Methods UK Biobank participants without prevalent arrhythmias were included. Co-primary study outcomes were supraventricular arrhythmias, bradyarrhythmias, and ventricular arrhythmias. Secondary outcomes were cardiac arrest, atrial fibrillation, and any arrhythmia. Associations of any CHIP [variant allele fraction (VAF) ≥ 2%], large CHIP (VAF ≥10%), and gene-specific CHIP subtypes with incident arrhythmias were evaluated using multivariable-adjusted Cox regression. Associations of CHIP with myocardial interstitial fibrosis [T1 measured using cardiac magnetic resonance (CMR)] were also tested. Results This study included 410 702 participants [CHIP: n = 13 892 (3.4%); large CHIP: n = 9191 (2.2%)]. Any and large CHIP were associated with multi-variable-adjusted hazard ratios of 1.11 [95% confidence interval (CI) 1.04–1.18; P = .001] and 1.13 (95% CI 1.05–1.22; P = .001) for supraventricular arrhythmias, 1.09 (95% CI 1.01–1.19; P = .031) and 1.13 (95% CI 1.03–1.25; P = .011) for bradyarrhythmias, and 1.16 (95% CI, 1.00–1.34; P = .049) and 1.22 (95% CI 1.03–1.45; P = .021) for ventricular arrhythmias, respectively. Associations were independent of coronary artery disease and heart failure. Associations were also heterogeneous across arrhythmia subtypes and strongest for cardiac arrest. Gene-specific analyses revealed an increased risk of arrhythmias across driver genes other than DNMT3A. Large CHIP was associated with 1.31-fold odds (95% CI 1.07–1.59; P = .009) of being in the top quintile of myocardial fibrosis by CMR. Conclusions CHIP may represent a novel risk factor for incident arrhythmias, indicating a potential target for modulation towards arrhythmia prevention and treatment.
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41.
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42.
  • Sechopoulos, Ioannis, et al. (författare)
  • Radiation dosimetry in digital breast tomosynthesis : report of AAPM Tomosynthesis Subcommittee Task Group 223.
  • 2014
  • Ingår i: Medical physics. - : Wiley. - 2473-4209 .- 0094-2405. ; 41:9
  • Tidskriftsartikel (refereegranskat)abstract
    • The radiation dose involved in any medical imaging modality that uses ionizing radiation needs to be well understood by the medical physics and clinical community. This is especially true of screening modalities. Digital breast tomosynthesis (DBT) has recently been introduced into the clinic and is being used for screening for breast cancer in the general population. Therefore, it is important that the medical physics community have the required information to be able to understand, estimate, and communicate the radiation dose levels involved in breast tomosynthesis imaging. For this purpose, the American Association of Physicists in Medicine Task Group 223 on Dosimetry in Tomosynthesis Imaging has prepared this report that discusses dosimetry in breast imaging in general, and describes a methodology and provides the data necessary to estimate mean breast glandular dose from a tomosynthesis acquisition. In an effort to maximize familiarity with the procedures and data provided in this Report, the methodology to perform the dose estimation in DBT is based as much as possible on that used in mammography dose estimation.
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43.
  • Smith, Hillary H., et al. (författare)
  • The grayness of the origin of life
  • 2021
  • Ingår i: Life. - : MDPI AG. - 2075-1729. ; 11:6
  • Tidskriftsartikel (refereegranskat)abstract
    • In the search for life beyond Earth, distinguishing the living from the non-living is paramount. However, this distinction is often elusive, as the origin of life is likely a stepwise evolutionary process, not a singular event. Regardless of the favored origin of life model, an inherent “grayness” blurs the theorized threshold defining life. Here, we explore the ambiguities between the biotic and the abiotic at the origin of life. The role of grayness extends into later transitions as well. By recognizing the limitations posed by grayness, life detection researchers will be better able to develop methods sensitive to prebiotic chemical systems and life with alternative biochemistries.
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