151
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Search for minimal supersymmetric standard model Higgs Bosons H / A and for a [Formula: see text] boson in the [Formula: see text] final state produced in pp collisions at [Formula: see text] TeV with the ATLAS detector. THE EUROPEAN PHYSICAL JOURNAL. C, PARTICLES AND FIELDS 2016; 76:585. [PMID: 28316491 PMCID: PMC5335571 DOI: 10.1140/epjc/s10052-016-4400-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/08/2016] [Accepted: 09/26/2016] [Indexed: 06/06/2023]
Abstract
A search for neutral Higgs bosons of the minimal supersymmetric standard model (MSSM) and for a heavneutral [Formula: see text] boson is performed using a data sample corresponding to an integrated luminosity of 3.2 fb[Formula: see text] from proton-proton collisions at [Formula: see text] [Formula: see text] recorded by the ATLAS detector at the LHC. The heavy resonance is assumed to decay to a [Formula: see text] pair with at least one [Formula: see text] lepton decaying to final states with hadrons and a neutrino. The search is performed in the mass range of 0.2-1.2 [Formula: see text] for the MSSM neutral Higgs bosons and 0.5-2.5 [Formula: see text] for the heavy neutral [Formula: see text] boson. The data are in good agreement with the background predicted by the Standard Model. The results are interpreted in MSSM and [Formula: see text] benchmark scenarios. The most stringent constraints on the MSSM [Formula: see text]-[Formula: see text] space exclude at 95 % confidence level (CL) [Formula: see text] for [Formula: see text] [Formula: see text] in the [Formula: see text] MSSM scenario. For the Sequential Standard Model, a [Formula: see text] mass up to 1.90 [Formula: see text] is excluded at 95 % CL and masses up to 1.82-2.17 [Formula: see text] are excluded for a [Formula: see text] of the strong flavour model.
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152
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Performance of pile-up mitigation techniques for jets in [Formula: see text] collisions at [Formula: see text] TeV using the ATLAS detector. THE EUROPEAN PHYSICAL JOURNAL. C, PARTICLES AND FIELDS 2016; 76:581. [PMID: 28316490 PMCID: PMC5335592 DOI: 10.1140/epjc/s10052-016-4395-z] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/14/2015] [Accepted: 09/26/2016] [Indexed: 05/07/2023]
Abstract
The large rate of multiple simultaneous proton-proton interactions, or pile-up, generated by the Large Hadron Collider in Run 1 required the development of many new techniques to mitigate the adverse effects of these conditions. This paper describes the methods employed in the ATLAS experiment to correct for the impact of pile-up on jet energy and jet shapes, and for the presence of spurious additional jets, with a primary focus on the large 20.3 [Formula: see text] data sample collected at a centre-of-mass energy of [Formula: see text]. The energy correction techniques that incorporate sophisticated estimates of the average pile-up energy density and tracking information are presented. Jet-to-vertex association techniques are discussed and projections of performance for the future are considered. Lastly, the extension of these techniques to mitigate the effect of pile-up on jet shapes using subtraction and grooming procedures is presented.
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153
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Comparisons of the efficacy and tolerability of mycophenolate mofetil and azathioprine as treatments for neuromyelitis optica and neuromyelitis optica spectrum disorder. Eur J Neurol 2016; 24:219-226. [PMID: 27783452 DOI: 10.1111/ene.13186] [Citation(s) in RCA: 56] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2016] [Accepted: 09/16/2016] [Indexed: 02/05/2023]
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154
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Search for gluinos in events with an isolated lepton, jets and missing transverse momentum at [Formula: see text] = 13 Te V with the ATLAS detector. THE EUROPEAN PHYSICAL JOURNAL. C, PARTICLES AND FIELDS 2016; 76:565. [PMID: 28316489 PMCID: PMC5335548 DOI: 10.1140/epjc/s10052-016-4397-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/16/2016] [Accepted: 09/26/2016] [Indexed: 06/06/2023]
Abstract
The results of a search for gluinos in final states with an isolated electron or muon, multiple jets and large missing transverse momentum using proton-proton collision data at a centre-of-mass energy of [Formula: see text] are presented. The dataset used was recorded in 2015 by the ATLAS experiment at the Large Hadron Collider and corresponds to an integrated luminosity of 3.2 fb[Formula: see text]. Six signal selections are defined that best exploit the signal characteristics. The data agree with the Standard Model background expectation in all six signal selections, and the largest deviation is a 2.1 standard deviation excess. The results are interpreted in a simplified model where pair-produced gluinos decay via the lightest chargino to the lightest neutralino. In this model, gluinos are excluded up to masses of approximately 1.6 Te V depending on the mass spectrum of the simplified model, thus surpassing the limits of previous searches.
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155
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Search for bottom squark pair production in proton-proton collisions at [Formula: see text] TeV with the ATLAS detector. THE EUROPEAN PHYSICAL JOURNAL. C, PARTICLES AND FIELDS 2016; 76:547. [PMID: 28316487 PMCID: PMC5335545 DOI: 10.1140/epjc/s10052-016-4382-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/29/2016] [Accepted: 09/16/2016] [Indexed: 05/30/2023]
Abstract
The result of a search for pair production of the supersymmetric partner of the Standard Model bottom quark ([Formula: see text]) is reported. The search uses 3.2 fb[Formula: see text] of pp collisions at [Formula: see text] TeV collected by the ATLAS experiment at the Large Hadron Collider in 2015. Bottom squarks are searched for in events containing large missing transverse momentum and exactly two jets identified as originating from b-quarks. No excess above the expected Standard Model background yield is observed. Exclusion limits at 95 % confidence level on the mass of the bottom squark are derived in phenomenological supersymmetric R-parity-conserving models in which the [Formula: see text] is the lightest squark and is assumed to decay exclusively via [Formula: see text], where [Formula: see text] is the lightest neutralino. The limits significantly extend previous results; bottom squark masses up to 800 (840) GeV are excluded for the [Formula: see text] mass below 360 (100) GeV whilst differences in mass above 100 GeV between the [Formula: see text] and the [Formula: see text] are excluded up to a [Formula: see text] mass of 500 GeV.
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156
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Search for new phenomena in different-flavour high-mass dilepton final states in pp collisions at [Formula: see text] Tev with the ATLAS detector. THE EUROPEAN PHYSICAL JOURNAL. C, PARTICLES AND FIELDS 2016; 76:541. [PMID: 28316486 PMCID: PMC5335544 DOI: 10.1140/epjc/s10052-016-4385-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/28/2016] [Accepted: 09/16/2016] [Indexed: 06/06/2023]
Abstract
A search is performed for a heavy particle decaying into different flavour dilepton pairs ([Formula: see text], [Formula: see text] or [Formula: see text]), using 3.2 fb[Formula: see text] of proton-proton collision data at [Formula: see text] TeV collected in 2015 by the ATLAS detector at the Large Hadron Collider. No excess over the Standard Model prediction is observed. Limits at the 95 % credibility level are set on the mass of a [Formula: see text] boson with lepton-flavour-violating couplings at 3.0, 2.7 and 2.6 TeV, and on the mass of a supersymmetric [Formula: see text] sneutrino with R-parity-violating couplings at 2.3, 2.2 and 1.9 TeV, for [Formula: see text], [Formula: see text] and [Formula: see text] final states, respectively. The results are also interpreted as limits on the threshold mass for quantum black hole production.
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157
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The performance of the jet trigger for the ATLAS detector during 2011 data taking. THE EUROPEAN PHYSICAL JOURNAL. C, PARTICLES AND FIELDS 2016; 76:526. [PMID: 28316483 PMCID: PMC5335543 DOI: 10.1140/epjc/s10052-016-4325-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/27/2016] [Accepted: 08/18/2016] [Indexed: 05/23/2023]
Abstract
The performance of the jet trigger for the ATLAS detector at the LHC during the 2011 data taking period is described. During 2011 the LHC provided proton-proton collisions with a centre-of-mass energy of 7 TeV and heavy ion collisions with a 2.76 TeV per nucleon-nucleon collision energy. The ATLAS trigger is a three level system designed to reduce the rate of events from the 40 MHz nominal maximum bunch crossing rate to the approximate 400 Hz which can be written to offline storage. The ATLAS jet trigger is the primary means for the online selection of events containing jets. Events are accepted by the trigger if they contain one or more jets above some transverse energy threshold. During 2011 data taking the jet trigger was fully efficient for jets with transverse energy above 25 GeV for triggers seeded randomly at Level 1. For triggers which require a jet to be identified at each of the three trigger levels, full efficiency is reached for offline jets with transverse energy above 60 GeV. Jets reconstructed in the final trigger level and corresponding to offline jets with transverse energy greater than 60 GeV, are reconstructed with a resolution in transverse energy with respect to offline jets, of better than 4 % in the central region and better than 2.5 % in the forward direction.
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158
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Search for supersymmetry in a final state containing two photons and missing transverse momentum in [Formula: see text] = 13 TeV [Formula: see text] collisions at the LHC using the ATLAS detector. THE EUROPEAN PHYSICAL JOURNAL. C, PARTICLES AND FIELDS 2016; 76:517. [PMID: 28303085 PMCID: PMC5332019 DOI: 10.1140/epjc/s10052-016-4344-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/30/2016] [Accepted: 08/30/2016] [Indexed: 06/06/2023]
Abstract
A search has been made for supersymmetry in a final state containing two photons and missing transverse momentum using the ATLAS detector at the Large Hadron Collider. The search makes use of [Formula: see text] of proton-proton collision data collected at a centre-of-mass energy of 13 TeV in 2015. Using a combination of data-driven and Monte-Carlo-based approaches, the Standard Model background is estimated to be [Formula: see text] events. No events are observed in the signal region; considering the expected background and its uncertainty, this observation implies a model-independent 95 % CL upper limit of 0.93 fb (3.0 events) on the visible cross section due to physics beyond the Standard Model. In the context of a generalized model of gauge-mediated supersymmetry breaking with a bino-like next-to-lightest supersymmetric particle, this leads to a lower limit of 1650 GeV on the mass of a degenerate octet of gluino states, independent of the mass of the lighter bino-like neutralino.
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159
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Study of the rare decays of [Formula: see text] and [Formula: see text] into muon pairs from data collected during the LHC Run 1 with the ATLAS detector. THE EUROPEAN PHYSICAL JOURNAL. C, PARTICLES AND FIELDS 2016; 76:513. [PMID: 28775663 PMCID: PMC5512627 DOI: 10.1140/epjc/s10052-016-4338-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/15/2016] [Accepted: 08/25/2016] [Indexed: 06/06/2023]
Abstract
A study of the decays [Formula: see text] and [Formula: see text] has been performed using data corresponding to an integrated luminosity of 25 fb[Formula: see text] of 7 and 8 TeV proton-proton collisions collected with the ATLAS detector during the LHC Run 1. For the [Formula: see text] dimuon decay, an upper limit on the branching fraction is set at [Formula: see text] at 95 % confidence level. For [Formula: see text], the branching fraction [Formula: see text] is measured. The results are consistent with the Standard Model expectation with a p value of 4.8 %, corresponding to 2.0 standard deviations.
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160
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Charged-particle distributions at low transverse momentum in [Formula: see text] TeV pp interactions measured with the ATLAS detector at the LHC. THE EUROPEAN PHYSICAL JOURNAL. C, PARTICLES AND FIELDS 2016; 76:502. [PMID: 28316503 PMCID: PMC5335502 DOI: 10.1140/epjc/s10052-016-4335-y] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/06/2016] [Accepted: 08/23/2016] [Indexed: 05/10/2023]
Abstract
Measurements of distributions of charged particles produced in proton-proton collisions with a centre-of-mass energy of 13 TeV are presented. The data were recorded by the ATLAS detector at the LHC and correspond to an integrated luminosity of 151 [Formula: see text]. The particles are required to have a transverse momentum greater than 100 MeV and an absolute pseudorapidity less than 2.5. The charged-particle multiplicity, its dependence on transverse momentum and pseudorapidity and the dependence of the mean transverse momentum on multiplicity are measured in events containing at least two charged particles satisfying the above kinematic criteria. The results are corrected for detector effects and compared to the predictions from several Monte Carlo event generators.
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161
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Search for Higgs and Z Boson Decays to ϕγ with the ATLAS Detector. PHYSICAL REVIEW LETTERS 2016; 117:111802. [PMID: 27661680 DOI: 10.1103/physrevlett.117.111802] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/14/2016] [Indexed: 06/06/2023]
Abstract
A search for the decays of the Higgs and Z bosons to a ϕ meson and a photon is performed with a pp collision data sample corresponding to an integrated luminosity of 2.7 fb^{-1} collected at sqrt[s]=13 TeV with the ATLAS detector at the LHC. No significant excess of events is observed above the background, and 95% confidence level upper limits on the branching fractions of the Higgs and Z boson decays to ϕγ of 1.4×10^{-3} and 8.3×10^{-6}, respectively, are obtained.
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162
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Measurement of exclusive γγ→W+W−production and search for exclusive Higgs boson production in ppcollisions at s=8 TeVusing the ATLAS detector. Int J Clin Exp Med 2016. [DOI: 10.1103/physrevd.94.032011] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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163
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Search for new phenomena in final states with an energetic jet and large missing transverse momentum in ppcollisions at s=13 TeVusing the ATLAS detector. Int J Clin Exp Med 2016. [DOI: 10.1103/physrevd.94.032005] [Citation(s) in RCA: 130] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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164
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[Effects of desmopressin acetate and pituitrin on proliferation, contraction, and secretion of hepatic stellate cells]. ZHONGHUA GAN ZANG BING ZA ZHI = ZHONGHUA GANZANGBING ZAZHI = CHINESE JOURNAL OF HEPATOLOGY 2016; 24:569-574. [PMID: 27788702 DOI: 10.3760/cma.j.issn.1007-3418.2016.08.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Objective: To investigate the effects of desmopressin acetate and pituitrin on the proliferation, contraction, and secretion of hepatic stellate cells (HSCs). Methods: The human HSC cell line LX-2 was selected as the research model. And three groups were designed: blank control group, desmopressin acetate group (three subgroups: 1×10-10mol/L, 1×10-9mol/L, and 1×10-8mol/L desmopressin acetate), and pituitrin group (three subgroups: 0.1 U/L, 1.0 U/L, and 10.0 U/L pituitrin). Water-soluble tetrazolium salt (WST)-1 assay was used to evaluate cell proliferation; collagen gel contraction assay was used to assess cell contraction; enzyme-linked immunosorbent assay (ELISA) was used to identify cell secretion. The data was subjected to one-way analysis of variance. Results: (1) The results of WST-1 assay showed that the values of A450in three desmopressin acetate subgroups (1×10-10mol/L, 1×10-9mol/L, and 1×10-8mol/L) were 0.459±0.017, 0.467±0.024, and 0.436±0.015, respectively. And the values of A450 in three pituitrin subgroups (0.1 U/L, 1.0 U/L, and 10.0 U/L) were 0.495±0.011, 0.507±0.015, and 0.501±0.009, respectively. Compared with the control group, the desmopressin acetate at high concentration significantly inhibited the cell proliferation (P< 0.05), but the pituitrin at three different concentrations significantly promoted the cell proliferation (P< 0.05). (2) The collagen gel area ratios in three desmopressin acetate subgroups (1×10-10mol/L, 1×10-9mol/L, and 1×10-8mol/L) were 77.07±4.42, 75.85±3.70, and 72.74±3.92, respectively. And the collagen gel area ratios in three pituitrin subgroups (0.1 U/L, 1.0 U/L, and 10.0 U/L) were 57.83±3.96, 50.28±6.69, and 43.56±7.68, respectively. Compared with the control group, the pituitrin at three different concentrations significantly reduced the collagen gel area (P< 0.01). (3) The matrix metalloproteinase(MMP)-2 concentrations in three desmopressin acetate subgroups (1×10-10mol/L, 1×10-9mol/L, and 1×10-8mol/L) were 13.321±0.098, 12.230±0.153, and 12.061±0.126, respectively. And the MMP-2 concentrations in three pituitrin subgroups (0.1 U/L, 1.0 U/L, and 10.0 U/L) were 12.899±0.150, 13.662±0.152, and 13.698±0.119, respectively. Compared with the control group, the desmopressin acetate at low concentration significantly increased the secretion of MMP-2 (P< 0.01); the desmopressin acetate at high concentration significantly decreased the MMP-2 concentration (P< 0.05); the pituitrin at three different concentrations significantly increased the MMP-2 concentration (P< 0.01). The transforming growth factor-beta 1 (TGF-β1) concentrations in three desmopressin acetate subgroups (1×10-10mol/L, 1×10-9mol/L, and 1×10-8mol/L) were 5.233±0.102, 17.749±0.188, and 36.060±0.227, respectively. And the TGF-β1 concentrations in three pituitrin subgroups (0.1 U/L, 1.0 U/L, and 10.0 U/L) were 15.615±0.099, 38.460±0.209, and 49.053±0.115, respectively. Compared with the control group, desmopressin acetate and pituitrin significantly promoted the secretion of TGF-β1 in a concentration-dependent manner (P< 0.01) and pituitrin had a stronger effect than desmopressin acetate (P< 0.01). Desmopressin acetate and pituitrin had no effect on the secretion of the collagenase type I and III (P> 0.05). Conclusion: Desmopressin acetate and pituitrin can induce the changes in the function and morphology of HSCs and may increase vascular resistance in the hepatic sinus. However, desmopressin acetate has less influence on HSCs than pituitrin.
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Novel Human Three-Domain Antibody Fragments Against sTNFα as Well as tmTNFα with High Affinity Generated by the Combination of Ribosome Display and E. coli Expression System. Scand J Immunol 2016; 83:267-78. [PMID: 26860639 DOI: 10.1111/sji.12417] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2015] [Accepted: 01/30/2016] [Indexed: 12/31/2022]
Abstract
Human tumour necrosis factor α (hTNFα) has been proved to be a validated therapeutic target in a number of immune-mediated inflammatory diseases (IMIDs). Fully human monoclonal antibodies (mAbs) that can neutralize soluble hTNFα (sTNFα) as well as transmembrane hTNFα (tmTNFα) are more desirable hTNFα antagonists. Here, we report that novel anti-hTNFα human low-molecular-weight MAbs have been selected and identified using both sTNFα and tmTNFα as target antigens by the combination of ribosome display and E. coli expression system for the first time. As a newly born engineering small molecular antibody, three-domain antibody fragment (VH /κ) provides an alternative promising molecular principle to generate biological agents for TNFα-dependent IMIDs. In this study, a panel of novel human VH /κs (F09, F21, F49 and F409) with high affinity (10(-10) -10(-9) mol/l) to neutralize sTNFα as well as tmTNFα was generated by the combination of ribosome display and E. coli expression system. Among the four clones, F21 and F409 could reduce cytotoxicity on L929 cells induced by sTNFα as well as tmTNFα effectively, and both of them had great potential to inhibit hTNFα-mediated NF-κB activation. Soluble F21 and F409 were also able to inhibit the binding of hTNFα to TNFR1 and TNFR2. The new human antibodies described here have desirable capability to neutralize sTNFα as well as tmTNFα effectively with high affinity and reasonable stability; this may provide an alternative approach for patients who are not responding adequately to currently available anti-TNFα agents.
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166
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Search for pair production of gluinos decaying via stop and sbottom in events with b-jets and large missing transverse momentum in ppcollisions at s=13 TeVwith the ATLAS detector. Int J Clin Exp Med 2016. [DOI: 10.1103/physrevd.94.032003] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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167
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Search for single production of vector-like quarks decaying into Wb in pp collisions at [Formula: see text] TeV with the ATLAS detector. THE EUROPEAN PHYSICAL JOURNAL. C, PARTICLES AND FIELDS 2016; 76:442. [PMID: 28303082 PMCID: PMC5331864 DOI: 10.1140/epjc/s10052-016-4281-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/19/2016] [Accepted: 07/25/2016] [Indexed: 06/06/2023]
Abstract
A search for singly produced vector-like Q quarks, where Q can be either a T quark with charge [Formula: see text] or a Y quark with charge [Formula: see text], is performed in proton-proton collisions recorded with the ATLAS detector at the LHC. The dataset corresponds to an integrated luminosity of 20.3 fb[Formula: see text] and was produced with a centre-of-mass energy of [Formula: see text] TeV. This analysis targets [Formula: see text] decays where the W boson decays leptonically. A veto on massive large-radius jets is used to reject the dominant [Formula: see text] background. The reconstructed Q-candidate mass, ranging from 0.4 to 1.2 TeV, is used in the search to discriminate signal from background processes. No significant deviation from the Standard Model expectation is observed, and limits are set on the [Formula: see text] cross-section times branching ratio. The results are also interpreted as limits on the QWb coupling and the mixing with the Standard Model sector for a singlet T quark or a Y quark from a doublet. T quarks with masses below 0.95 TeV are excluded at 95 % confidence level, assuming a unit coupling and a BR[Formula: see text], whereas the expected limit is 1.10 TeV.
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168
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Charged-particle distributions in pp interactions at [Formula: see text] measured with the ATLAS detector. THE EUROPEAN PHYSICAL JOURNAL. C, PARTICLES AND FIELDS 2016; 76:403. [PMID: 28280450 PMCID: PMC5321437 DOI: 10.1140/epjc/s10052-016-4203-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/09/2016] [Accepted: 06/12/2016] [Indexed: 05/10/2023]
Abstract
This paper presents measurements of distributions of charged particles which are produced in proton-proton collisions at a centre-of-mass energy of [Formula: see text] and recorded by the ATLAS detector at the LHC. A special dataset recorded in 2012 with a small number of interactions per beam crossing (below 0.004) and corresponding to an integrated luminosity of 160 [Formula: see text] was used. A minimum-bias trigger was utilised to select a data sample of more than 9 million collision events. The multiplicity, pseudorapidity, and transverse momentum distributions of charged particles are shown in different regions of kinematics and charged-particle multiplicity, including measurements of final states at high multiplicity. The results are corrected for detector effects and are compared to the predictions of various Monte Carlo event generator models which simulate the full hadronic final state.
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169
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Search for squarks and gluinos in final states with jets and missing transverse momentum at [Formula: see text] =13 [Formula: see text]with the ATLAS detector. THE EUROPEAN PHYSICAL JOURNAL. C, PARTICLES AND FIELDS 2016; 76:392. [PMID: 28747849 PMCID: PMC5501190 DOI: 10.1140/epjc/s10052-016-4184-8] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/13/2016] [Accepted: 06/08/2016] [Indexed: 05/30/2023]
Abstract
A search for squarks and gluinos in final states containing hadronic jets, missing transverse momentum but no electrons or muons is presented. The data were recorded in 2015 by the ATLAS experiment in [Formula: see text] proton-proton collisions at the Large Hadron Collider. No excess above the Standard Model background expectation was observed in 3.2 [Formula: see text] of analyzed data. Results are interpreted within simplified models that assume R-parity is conserved and the neutralino is the lightest supersymmetric particle. An exclusion limit at the 95 % confidence level on the mass of the gluino is set at 1.51 [Formula: see text] for a simplified model incorporating only a gluino octet and the lightest neutralino, assuming the lightest neutralino is massless. For a simplified model involving the strong production of mass-degenerate first- and second-generation squarks, squark masses below 1.03 [Formula: see text] are excluded for a massless lightest neutralino. These limits substantially extend the region of supersymmetric parameter space excluded by previous measurements with the ATLAS detector.
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170
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Measurement of event-shape observables in [Formula: see text] events in pp collisions at [Formula: see text] [Formula: see text] with the ATLAS detector at the LHC. THE EUROPEAN PHYSICAL JOURNAL. C, PARTICLES AND FIELDS 2016; 76:375. [PMID: 28280446 PMCID: PMC5321395 DOI: 10.1140/epjc/s10052-016-4176-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/01/2016] [Accepted: 06/02/2016] [Indexed: 06/06/2023]
Abstract
Event-shape observables measured using charged particles in inclusive Z-boson events are presented, using the electron and muon decay modes of the Z bosons. The measurements are based on an integrated luminosity of [Formula: see text] of proton-proton collisions recorded by the ATLAS detector at the LHC at a centre-of-mass energy [Formula: see text] [Formula: see text]. Charged-particle distributions, excluding the lepton-antilepton pair from the Z-boson decay, are measured in different ranges of transverse momentum of the Z boson. Distributions include multiplicity, scalar sum of transverse momenta, beam thrust, transverse thrust, spherocity, and [Formula: see text]-parameter, which are in particular sensitive to properties of the underlying event at small values of the Z-boson transverse momentum. The measured observables are compared with predictions from Pythia 8, Sherpa, and Herwig 7. Typically, all three Monte Carlo generators provide predictions that are in better agreement with the data at high Z-boson transverse momenta than at low Z-boson transverse momenta, and for the observables that are less sensitive to the number of charged particles in the event.
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171
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Search for metastable heavy charged particles with large ionization energy loss in ppcollisions at s=13 TeVusing the ATLAS experiment. Int J Clin Exp Med 2016. [DOI: 10.1103/physrevd.93.112015] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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172
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Improving production of extracellular proteases by random mutagenesis and biochemical characterization of a serine protease in Bacillus subtilis S1-4. GENETICS AND MOLECULAR RESEARCH 2016; 15:gmr7831. [PMID: 27323184 DOI: 10.4238/gmr.15027831] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
The feather is a valuable by-product with a huge annual yield produced by the poultry industry. Degradation of feathers by microorganisms is a prerequisite to utilize this insoluble protein resource. To improve the degrading efficiency of feathers, mutagenesis of the bacterium Bacillus subtilis S1-4 was performed. By combining ultraviolet irradiation and N-methyl-N'-nitro-N-nitrosoguanidine treatment for mutagenesis, a high protease-producing mutant (UMU4) of B. subtilis S1-4 was selected, which exhibited 2.5-fold higher extracellular caseinolytic activity than did the wild-type strain. UMU4 degraded chicken feathers more efficiently, particularly for the release of soluble proteins from the feathers, compared to the wild-type strain. Furthermore, an extracellular protease with a molecular weight of 45 kDa, as determined by SDS-PAGE, was purified from UMU4. Biochemical characterization indicated that the caseinolytic activity of the protease was largely inhibited by phenylmethanesulfonyl fluoride, suggesting that the purified enzyme is a serine protease. This protease was highly active over a wide range of pHs (6.0 to 12.0) and temperatures (50° to 75°C) with an optimal pH and temperature of 8.0 and 65°C, respectively. The purified enzyme exhibited good thermostability with a 72.2 min half-life of thermal denaturation at 60°C. In addition, this protease was not sensitive to heavy metal ions, surfactants, or oxidative reagents. In conclusion, strain improvement for protease production can serve as an alternative strategy to promote feather degradation. The UMU4 mutant of B. subtilis and its serine protease could be potentially used in various industries.
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173
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Measurement of the charged-particle multiplicity inside jets from [Formula: see text][Formula: see text] pp collisions with the ATLAS detector. THE EUROPEAN PHYSICAL JOURNAL. C, PARTICLES AND FIELDS 2016; 76:322. [PMID: 28280438 PMCID: PMC5321259 DOI: 10.1140/epjc/s10052-016-4126-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/03/2016] [Accepted: 05/04/2016] [Indexed: 05/31/2023]
Abstract
The number of charged particles inside jets is a widely used discriminant for identifying the quark or gluon nature of the initiating parton and is sensitive to both the perturbative and non-perturbative components of fragmentation. This paper presents a measurement of the average number of charged particles with [Formula: see text] [Formula: see text] inside high-momentum jets in dijet events using 20.3 fb[Formula: see text] of data recorded with the ATLAS detector in pp collisions at [Formula: see text] [Formula: see text] collisions at the LHC. The jets considered have transverse momenta from 50 [Formula: see text] up to and beyond 1.5 [Formula: see text]. The reconstructed charged-particle track multiplicity distribution is unfolded to remove distortions from detector effects and the resulting charged-particle multiplicity is compared to several models. Furthermore, quark and gluon jet fractions are used to extract the average charged-particle multiplicity for quark and gluon jets separately.
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174
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Determination of Tryptophan, Glutathione, and Uric Acid in Human Whole Blood Extract by Capillary Electrophoresis with a One-Step Electrochemically Reduced Graphene Oxide Modified Microelectrode. Chromatographia 2016. [DOI: 10.1007/s10337-016-3115-z] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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175
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Algebraic approach to geometric Quantum Speed Limits in triatomic molecules. JOURNAL OF ATOMIC AND MOLECULAR SCIENCES 2016. [DOI: 10.4208/jams.062016.081216a] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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176
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Muon reconstruction performance of the ATLAS detector in proton-proton collision data at [Formula: see text]=13 TeV. THE EUROPEAN PHYSICAL JOURNAL. C, PARTICLES AND FIELDS 2016; 76:292. [PMID: 28280436 PMCID: PMC5321258 DOI: 10.1140/epjc/s10052-016-4120-y] [Citation(s) in RCA: 80] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/18/2016] [Accepted: 04/29/2016] [Indexed: 05/07/2023]
Abstract
This article documents the performance of the ATLAS muon identification and reconstruction using the LHC dataset recorded at [Formula: see text] TeV in 2015. Using a large sample of [Formula: see text] and [Formula: see text] decays from 3.2 fb[Formula: see text] of pp collision data, measurements of the reconstruction efficiency, as well as of the momentum scale and resolution, are presented and compared to Monte Carlo simulations. The reconstruction efficiency is measured to be close to [Formula: see text] over most of the covered phase space ([Formula: see text] and [Formula: see text] GeV). The isolation efficiency varies between 93 and [Formula: see text] depending on the selection applied and on the momentum of the muon. Both efficiencies are well reproduced in simulation. In the central region of the detector, the momentum resolution is measured to be [Formula: see text] ([Formula: see text]) for muons from [Formula: see text] ([Formula: see text]) decays, and the momentum scale is known with an uncertainty of [Formula: see text]. In the region [Formula: see text], the [Formula: see text] resolution for muons from [Formula: see text] decays is [Formula: see text] while the precision of the momentum scale for low-[Formula: see text] muons from [Formula: see text] decays is about [Formula: see text].
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177
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Measurement of the transverse momentum and [Formula: see text] distributions of Drell-Yan lepton pairs in proton-proton collisions at [Formula: see text] TeV with the ATLAS detector. THE EUROPEAN PHYSICAL JOURNAL. C, PARTICLES AND FIELDS 2016; 76:291. [PMID: 28280435 PMCID: PMC5321297 DOI: 10.1140/epjc/s10052-016-4070-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/08/2015] [Accepted: 04/08/2016] [Indexed: 05/22/2023]
Abstract
Distributions of transverse momentum [Formula: see text] and the related angular variable [Formula: see text] of Drell–Yan lepton pairs are measured in 20.3 fb[Formula: see text] of proton–proton collisions at [Formula: see text] TeV with the ATLAS detector at the LHC. Measurements in electron-pair and muon-pair final states are corrected for detector effects and combined. Compared to previous measurements in proton–proton collisions at [Formula: see text] TeV, these new measurements benefit from a larger data sample and improved control of systematic uncertainties. Measurements are performed in bins of lepton-pair mass above, around and below the Z-boson mass peak. The data are compared to predictions from perturbative and resummed QCD calculations. For values of [Formula: see text] the predictions from the Monte Carlo generator ResBos are generally consistent with the data within the theoretical uncertainties. However, at larger values of [Formula: see text] this is not the case. Monte Carlo generators based on the parton-shower approach are unable to describe the data over the full range of [Formula: see text] while the fixed-order prediction of Dynnlo falls below the data at high values of [Formula: see text]. ResBos and the parton-shower Monte Carlo generators provide a much better description of the evolution of the [Formula: see text] and [Formula: see text] distributions as a function of lepton-pair mass and rapidity than the basic shape of the data.
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Measurement of the differential cross-sections of prompt and non-prompt production of [Formula: see text] and [Formula: see text] in pp collisions at [Formula: see text] and 8 TeV with the ATLAS detector. THE EUROPEAN PHYSICAL JOURNAL. C, PARTICLES AND FIELDS 2016; 76:283. [PMID: 28280433 PMCID: PMC5321264 DOI: 10.1140/epjc/s10052-016-4050-8] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/14/2015] [Accepted: 03/31/2016] [Indexed: 06/06/2023]
Abstract
The production rates of prompt and non-prompt [Formula: see text] and [Formula: see text] mesons in their dimuon decay modes are measured using 2.1 and 11.4 fb[Formula: see text] of data collected with the ATLAS experiment at the Large Hadron Collider, in proton-proton collisions at [Formula: see text] and 8 respectively. Production cross-sections for prompt as well as non-prompt sources, ratios of [Formula: see text] to [Formula: see text] production, and the fractions of non-prompt production for [Formula: see text] and [Formula: see text] are measured as a function of meson transverse momentum and rapidity. The measurements are compared to theoretical predictions.
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179
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High Glucose and Lipopolysaccharide Activate NOD1- RICK-NF-κB Inflammatory Signaling in Mesangial Cells. Exp Clin Endocrinol Diabetes 2016; 124:512-517. [PMID: 27169686 DOI: 10.1055/s-0042-105641] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
Systemic and local low-grade inflammation and release of proinflammatory cytokines are implicated in the development and progression of diabetes mellitus (DM) and diabetic nephropathy (DN). The TLR2, TLR4, and NLRP3 inflammasomes of the innate immune system produce various proinflammatory cytokines and are critically involved in inflammatory responses in kidney tissues. The NOD-like receptor (NLR) NOD1 is involved in the NF-κB inflammatory signaling pathway and has an important role in the development of insulin resistance. Extracellular stimuli such as high glucose or lipopolysaccharide (LPS) can induce NOD1-RICK to activate NF-κB, which is associated with diabetes and other chronic inflammatory conditions. It is currently unknown whether NOD1-RICK-mediated NF-κB signaling is involved in DN pathogenesis. In this study, expression of NOD1, RICK, IκBα, NF-κB and IL-1β was detected in cultured rat glomerular mesangial cells (rGMCs) stimulated with high concentrations of glucose and LPS. ML130, a NOD1 inhibitor, was used to investigate the role of the NOD1 signaling pathway in DN inflammation. Our results showed that high glucose or LPS increased the protein and mRNA expression of NOD1, RICK,NF-κBp65 and IL-1β, but attenuated IκBα expression (P<0.05). These changes were synergistically enhanced by stimulating with high glucose and LPS. However, pretreatment with the NOD1 inhibitor ML130 significantly reversed these changes (P<0.05). These combined results support the hypothesis that high glucose and LPS can activate the NOD1-RICK-NF-κB inflammatory signaling pathway via the NOD1 receptor, and may participate in the development of DN.
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180
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Search for supersymmetry at [Formula: see text] TeV in final states with jets and two same-sign leptons or three leptons with the ATLAS detector. THE EUROPEAN PHYSICAL JOURNAL. C, PARTICLES AND FIELDS 2016; 76:259. [PMID: 28280429 PMCID: PMC5321255 DOI: 10.1140/epjc/s10052-016-4095-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/03/2016] [Accepted: 04/18/2016] [Indexed: 05/30/2023]
Abstract
A search for strongly produced supersymmetric particles is conducted using signatures involving multiple energetic jets and either two isolated leptons (e or [Formula: see text]) with the same electric charge or at least three isolated leptons. The search also utilises b-tagged jets, missing transverse momentum and other observables to extend its sensitivity. The analysis uses a data sample of proton-proton collisions at [Formula: see text] TeV recorded with the ATLAS detector at the Large Hadron Collider in 2015 corresponding to a total integrated luminosity of 3.2 fb[Formula: see text]. No significant excess over the Standard Model expectation is observed. The results are interpreted in several simplified supersymmetric models and extend the exclusion limits from previous searches. In the context of exclusive production and simplified decay modes, gluino masses are excluded at [Formula: see text] confidence level up to 1.1-1.3 TeV for light neutralinos (depending on the decay channel), and bottom squark masses are also excluded up to 540 GeV. In the former scenarios, neutralino masses are also excluded up to 550-850 GeV for gluino masses around 1 TeV.
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181
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The role of regulatory T cells during Plasmodium chabaudi chabaudi AS infection in BALB/c mice. Parasite Immunol 2016; 38:439-50. [PMID: 27139002 DOI: 10.1111/pim.12333] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2015] [Accepted: 04/26/2016] [Indexed: 11/30/2022]
Abstract
An inappropriate immune response to parasite infection is one of the primary drivers of malaria pathogenesis. Regulatory T cells (Tregs), an important subset of CD4(+) T cells, can maintain self-tolerance and prevent autoimmune diseases. However, there is little consensus about their role in malaria pathogenesis. In this study, we transiently depleted Tregs (CD25(+) T cells) using an anti-CD25 mAb (7D4 clone) at different time points following Plasmodium chabaudi chabaudi AS infection in BALB/c mice and investigated the effect of depletion of Tregs in this model. In control mice, Tregs proliferated significantly and their suppressive function was enhanced after infection. IL-10 was increased drastically during infection. Depletion of Tregs at various time points can lead to divergent outcomes. When Tregs were depleted prior to or during the early phase of infection, most mice survived and had a robust Th1 immune response. In contrast, when Tregs were depleted close to peak parasitemia, all mice died as a result of inflammation. Taken together, these data suggest that in P. c. chabaudi AS-infected BALB/c mice, Tregs inhibit the Th1 response and macrophage activation, leading to increased parasite load; however, they also control inflammation-mediated pathology by secreting high levels of IL-10.
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182
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Observation of Long-Range Elliptic Azimuthal Anisotropies in sqrt[s]=13 and 2.76 TeV pp Collisions with the ATLAS Detector. PHYSICAL REVIEW LETTERS 2016; 116:172301. [PMID: 27176515 DOI: 10.1103/physrevlett.116.172301] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/15/2015] [Indexed: 06/05/2023]
Abstract
ATLAS has measured two-particle correlations as a function of the relative azimuthal angle, Δϕ, and pseudorapidity, Δη, in sqrt[s]=13 and 2.76 TeV pp collisions at the LHC using charged particles measured in the pseudorapidity interval |η|<2.5. The correlation functions evaluated in different intervals of measured charged-particle multiplicity show a multiplicity-dependent enhancement at Δϕ∼0 that extends over a wide range of Δη, which has been referred to as the "ridge." Per-trigger-particle yields, Y(Δϕ), are measured over 2<|Δη|<5. For both collision energies, the Y(Δϕ) distribution in all multiplicity intervals is found to be consistent with a linear combination of the per-trigger-particle yields measured in collisions with less than 20 reconstructed tracks, and a constant combinatoric contribution modulated by cos(2Δϕ). The fitted Fourier coefficient, v_{2,2}, exhibits factorization, suggesting that the ridge results from per-event cos(2ϕ) modulation of the single-particle distribution with Fourier coefficients v_{2}. The v_{2} values are presented as a function of multiplicity and transverse momentum. They are found to be approximately constant as a function of multiplicity and to have a p_{T} dependence similar to that measured in p+Pb and Pb+Pb collisions. The v_{2} values in the 13 and 2.76 TeV data are consistent within uncertainties. These results suggest that the ridge in pp collisions arises from the same or similar underlying physics as observed in p+Pb collisions, and that the dynamics responsible for the ridge has no strong sqrt[s] dependence.
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183
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A new method to distinguish hadronically decaying boosted Z bosons from W bosons using the ATLAS detector. THE EUROPEAN PHYSICAL JOURNAL. C, PARTICLES AND FIELDS 2016; 76:238. [PMID: 28280428 PMCID: PMC5320951 DOI: 10.1140/epjc/s10052-016-4065-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/17/2015] [Accepted: 04/08/2016] [Indexed: 06/06/2023]
Abstract
The distribution of particles inside hadronic jets produced in the decay of boosted W and Z bosons can be used to discriminate such jets from the continuum background. Given that a jet has been identified as likely resulting from the hadronic decay of a boosted W or Z boson, this paper presents a technique for further differentiating Z bosons from W bosons. The variables used are jet mass, jet charge, and a b-tagging discriminant. A likelihood tagger is constructed from these variables and tested in the simulation of [Formula: see text] for bosons in the transverse momentum range 200 GeV [Formula: see text] 400 GeV in [Formula: see text] TeV pp collisions with the ATLAS detector at the LHC. For Z-boson tagging efficiencies of [Formula: see text], 50, and [Formula: see text], one can achieve [Formula: see text]-boson tagging rejection factors ([Formula: see text]) of 1.7, 8.3 and 1000, respectively. It is not possible to measure these efficiencies in the data due to the lack of a pure sample of high [Formula: see text], hadronically decaying Z bosons. However, the modelling of the tagger inputs for boosted W bosons is studied in data using a [Formula: see text]-enriched sample of events in 20.3 fb[Formula: see text] of data at [Formula: see text] TeV. The inputs are well modelled within uncertainties, which builds confidence in the expected tagger performance.
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184
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Probing lepton flavour violation via neutrinoless [Formula: see text] decays with the ATLAS detector. THE EUROPEAN PHYSICAL JOURNAL. C, PARTICLES AND FIELDS 2016; 76:232. [PMID: 28280425 PMCID: PMC5320940 DOI: 10.1140/epjc/s10052-016-4041-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/15/2016] [Accepted: 03/30/2016] [Indexed: 06/06/2023]
Abstract
This article presents the sensitivity of the ATLAS experiment to the lepton-flavour-violating decays of [Formula: see text]. A method utilising the production of [Formula: see text] leptons via [Formula: see text] decays is used. This method is applied to the sample of 20.3 fb[Formula: see text] of pp collision data at a centre-of-mass energy of 8 TeV collected by the ATLAS experiment at the LHC in 2012. No event is observed passing the selection criteria, and the observed (expected) upper limit on the [Formula: see text] lepton branching fraction into three muons, [Formula: see text], is [Formula: see text] ([Formula: see text]) at 90 % confidence level.
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[Arthroscopic all-inside reconstruction for posterior cruciate ligament and popliteus tendon compared with popliteofibular ligament reconstruction: clinical outcome of minimum 2-year follow-up]. BEIJING DA XUE XUE BAO. YI XUE BAN = JOURNAL OF PEKING UNIVERSITY. HEALTH SCIENCES 2016; 48:237-243. [PMID: 27080274] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
OBJECTIVE To describe the clinical results of a one-stage operation for posterior cruciate ligament reconstruction and a posterolateral corner reconstruction of popliteus tendon reconstruction, compared with an open popliteofibular ligament reconstruction. METHODS Our study included 33 patients who had undergone posterior cruciate ligament reconstruction with use of an achilles tendon-bone allograft and posterolateral corner reconstruction with arthroscopic anatomical reconstruction of popliteus tendon or open reconstruction of popliteofibular ligament. The patients were assessed for knee instability with use of the dial test at 30° and 90°, together with posterior stress radiography and KT-1000 measurement. RESULTS The mean time of follow-up was more than 2 years. At the final follow-up evaluation, the tibial posterior translation as measured by stress radiography at 90° of knee flexion, the anterior-posterior translation as measured by KT-1000, and the external rotation of tibia as measured by dial test were reduced postoperatively (P<0.001) in both groups. Between the two groups, the preoperative tibial posterior translation as measured by stress radiography and the preoperative mean anterior-posterior translation as measured by KT-1000 in the popliteofibular ligament group were a little more than those in the popliteus tendon group (P=0.014, P<0.001). But the other comparisons were not significantly different (P>0.05). The final flexion losses were 3.33°±4.88° and 3.06°±3.38° for the two groups. CONCLUSION Combined with posterior cruciate ligament reconstruction, anatomical posterolateral corner reconstruction of the popliteus tendon and open reconstruction of popliteofibular ligament showed similar outcomes. This study demonstrated that both posterolateral corner reconstruction techniques were a reliable alternative method in addressing posterolateral corner and posterior cruciate ligament insufficiency of the knee.
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186
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Search for new phenomena in events with at least three photons collected in pp collisions at [Formula: see text] = 8 TeV with the ATLAS detector. THE EUROPEAN PHYSICAL JOURNAL. C, PARTICLES AND FIELDS 2016; 76:210. [PMID: 28260974 PMCID: PMC5312246 DOI: 10.1140/epjc/s10052-016-4034-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/17/2015] [Accepted: 03/25/2016] [Indexed: 06/06/2023]
Abstract
Results of a search for new phenomena in events with at least three photons are reported. Data from proton-proton collisions at a centre-of-mass energy of 8 TeV, corresponding to an integrated luminosity of 20.3 fb[Formula: see text], were collected with the ATLAS detector at the LHC. The observed data are well described by the Standard Model. Limits at the 95 % confidence level on new phenomena are presented based on the rate of events in an inclusive signal region and a restricted signal region targeting the rare decay [Formula: see text], as well as di-photon and tri-photon resonance searches. For a Standard Model Higgs boson decaying to four photons via a pair of intermediate pseudoscalar particles (a), limits are found to be [Formula: see text] for 10 GeV [Formula: see text] 62 GeV. Limits are also presented for Higgs boson-like scalars (H) for [Formula: see text] 125 GeV, and for a [Formula: see text] decaying to three photons via [Formula: see text]. Additionally, the observed limit on the branching ratio of the Z boson decay to three photons is found to be BR[Formula: see text], a result five times stronger than the previous result from LEP.
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187
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Measurement of the centrality dependence of the charged-particle pseudorapidity distribution in proton-lead collisions at [Formula: see text] TeV with the ATLAS detector. THE EUROPEAN PHYSICAL JOURNAL. C, PARTICLES AND FIELDS 2016; 76:199. [PMID: 28260972 PMCID: PMC5312138 DOI: 10.1140/epjc/s10052-016-4002-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/05/2015] [Accepted: 03/07/2016] [Indexed: 06/06/2023]
Abstract
The centrality dependence of the mean charged-particle multiplicity as a function of pseudorapidity is measured in approximately 1 [Formula: see text]b[Formula: see text] of proton-lead collisions at a nucleon-nucleon centre-of-mass energy of [Formula: see text] [Formula: see text] using the ATLAS detector at the Large Hadron Collider. Charged particles with absolute pseudorapidity less than 2.7 are reconstructed using the ATLAS pixel detector. The [Formula: see text] collision centrality is characterised by the total transverse energy measured in the Pb-going direction of the forward calorimeter. The charged-particle pseudorapidity distributions are found to vary strongly with centrality, with an increasing asymmetry between the proton-going and Pb-going directions as the collisions become more central. Three different estimations of the number of nucleons participating in the [Formula: see text] collision have been carried out using the Glauber model as well as two Glauber-Gribov inspired extensions to the Glauber model. Charged-particle multiplicities per participant pair are found to vary differently for these three models, highlighting the importance of including colour fluctuations in nucleon-nucleon collisions in the modelling of the initial state of [Formula: see text] collisions.
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Structure of mitochondrial DNA control region and genetic diversity of Moschus berezovskii populations in Shaanxi Province. GENETICS AND MOLECULAR RESEARCH 2016; 15:gmr7578. [PMID: 27173215 DOI: 10.4238/gmr.15027578] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
In China, Moschus berezovskii (forest musk deer), a first-class national protected animal, was earlier widely distributed. However, wild populations of the forest musk deer have declined because of human activity and habitat loss. In order to gather useful information for its conservation and management, we investigated the genetic diversity and population structure of this species by analyzing a 632-bp fragment of mitochondrial DNA (mtDNA) control region in three wild populations in Shaanxi Province, China. The average A+T content (64.1%) of mtDNA was higher than that of G+C (35.9%). A total of 178 variable sites (about 28.03% of the total nucleotides in the sequence) were detected in 71 individuals. The nucleotide diversity (PI) in the 71 individuals was 0.04688, and the average nucleotide differences (K) were 21.238. The 71 individuals belonged to 33 haplotypes according to the determined sequences. The average genetic distance (P) among the haplotypes of the species was 0.169. The phylogenetic tree constructed using the neighbor-joining method revealed that these individuals were clustered into three groups, but the individual distribution in those groups was disordered. These data indicated the variation and rich genetic diversity in the three populations of M. berezovskii. Compared to the wild population in Longxian, those in Liuba and Fengxian had a close kinship. The present results indicated no signs of inbreeding or a decline in genetic diversity in the wild M. berezovskii population.
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Identification of boosted, hadronically decaying W bosons and comparisons with ATLAS data taken at [Formula: see text] TeV. THE EUROPEAN PHYSICAL JOURNAL. C, PARTICLES AND FIELDS 2016; 76:154. [PMID: 27471432 PMCID: PMC4946871 DOI: 10.1140/epjc/s10052-016-3978-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/22/2015] [Accepted: 02/25/2016] [Indexed: 06/06/2023]
Abstract
This paper reports a detailed study of techniques for identifying boosted, hadronically decaying W bosons using 20.3 fb[Formula: see text] of proton-proton collision data collected by the ATLAS detector at the LHC at a centre-of-mass energy [Formula: see text]. A range of techniques for optimising the signal jet mass resolution are combined with various jet substructure variables. The results of these studies in Monte Carlo simulations show that a simple pairwise combination of groomed jet mass and one substructure variable can provide a 50 % efficiency for identifying W bosons with transverse momenta larger than 200 GeV while maintaining multijet background efficiencies of 2-4 % for jets with the same transverse momentum. These signal and background efficiencies are confirmed in data for a selection of tagging techniques.
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190
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Measurement of the ZZ Production Cross Section in pp Collisions at sqrt[s]=13 TeV with the ATLAS Detector. PHYSICAL REVIEW LETTERS 2016; 116:101801. [PMID: 27015473 DOI: 10.1103/physrevlett.116.101801] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/17/2015] [Indexed: 06/05/2023]
Abstract
The ZZ production cross section in proton-proton collisions at 13 TeV center-of-mass energy is measured using 3.2 fb^{-1} of data recorded with the ATLAS detector at the Large Hadron Collider. The considered Z boson candidates decay to an electron or muon pair of mass 66-116 GeV. The cross section is measured in a fiducial phase space reflecting the detector acceptance. It is also extrapolated to a total phase space for Z bosons in the same mass range and of all decay modes, giving 16.7_{-2.0}^{+2.2}(stat)+0.9/-0.7(syst)+1.0/-0.7(lumi) pb. The results agree with standard model predictions.
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191
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Measurement of the differential cross-section of highly boosted top quarks as a function of their transverse momentum in s=8 TeVproton-proton collisions using the ATLAS detector. Int J Clin Exp Med 2016. [DOI: 10.1103/physrevd.93.032009] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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192
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Measurement of the charge asymmetry in top-quark pair production in the lepton-plus-jets final state in pp collision data at [Formula: see text] with the ATLAS detector. THE EUROPEAN PHYSICAL JOURNAL. C, PARTICLES AND FIELDS 2016; 76:87. [PMID: 27069416 PMCID: PMC4811088 DOI: 10.1140/epjc/s10052-016-3910-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/09/2015] [Accepted: 01/26/2016] [Indexed: 06/01/2023]
Abstract
This paper reports inclusive and differential measurements of the [Formula: see text] charge asymmetry [Formula: see text] in [Formula: see text] of [Formula: see text][Formula: see text] collisions recorded by the ATLAS experiment at the Large Hadron Collider at CERN. Three differential measurements are performed as a function of the invariant mass, transverse momentum and longitudinal boost of the [Formula: see text] system. The [Formula: see text] pairs are selected in the single-lepton channels (e or [Formula: see text]) with at least four jets, and a likelihood fit is used to reconstruct the [Formula: see text] event kinematics. A Bayesian unfolding procedure is performed to infer the asymmetry at parton level from the observed data distribution. The inclusive [Formula: see text] charge asymmetry is measured to be [Formula: see text] (stat. [Formula: see text] syst.). The inclusive and differential measurements are compatible with the values predicted by the Standard Model.
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Search for direct top squark pair production in final states with two tau leptons in pp collisions at [Formula: see text] TeV with the ATLAS detector. THE EUROPEAN PHYSICAL JOURNAL. C, PARTICLES AND FIELDS 2016; 76:81. [PMID: 27069414 PMCID: PMC4810293 DOI: 10.1140/epjc/s10052-016-3897-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/18/2015] [Accepted: 01/14/2016] [Indexed: 06/05/2023]
Abstract
A search for direct pair production of the supersymmetric partner of the top quark, decaying via a scalar tau to a nearly massless gravitino, has been performed using 20 fb[Formula: see text] of proton-proton collision data at [Formula: see text]. The data were collected by the ATLAS experiment at the LHC in 2012. Top squark candidates are searched for in events with either two hadronically decaying tau leptons, one hadronically decaying tau and one light lepton, or two light leptons. No significant excess over the Standard Model expectation is found. Exclusion limits at [Formula: see text] confidence level are set as a function of the top squark and scalar tau masses. Depending on the scalar tau mass, ranging from the [Formula: see text] LEP limit to the top squark mass, lower limits between 490 and [Formula: see text] are placed on the top squark mass within the model considered.
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The TCA cycle transferase DLST is important for MYC-mediated leukemogenesis. Leukemia 2016; 30:1365-74. [PMID: 26876595 DOI: 10.1038/leu.2016.26] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2015] [Revised: 12/21/2015] [Accepted: 02/01/2016] [Indexed: 12/22/2022]
Abstract
Despite the pivotal role of MYC in the pathogenesis of T-cell acute lymphoblastic leukemia (T-ALL) and many other cancers, the mechanisms underlying MYC-mediated tumorigenesis remain inadequately understood. Here we utilized a well-characterized zebrafish model of Myc-induced T-ALL for genetic studies to identify novel genes contributing to disease onset. We found that heterozygous inactivation of a tricarboxylic acid (TCA) cycle enzyme, dihydrolipoamide S-succinyltransferase (Dlst), significantly delayed tumor onset in zebrafish without detectable effects on fish development. DLST is the E2 transferase of the α-ketoglutarate (α-KG) dehydrogenase complex (KGDHC), which converts α-KG to succinyl-CoA in the TCA cycle. RNAi knockdown of DLST led to decreased cell viability and induction of apoptosis in human T-ALL cell lines. Polar metabolomics profiling revealed that the TCA cycle was disrupted by DLST knockdown in human T-ALL cells, as demonstrated by an accumulation of α-KG and a decrease of succinyl-CoA. Addition of succinate, the downstream TCA cycle intermediate, to human T-ALL cells was sufficient to rescue defects in cell viability caused by DLST inactivation. Together, our studies uncovered an important role for DLST in MYC-mediated leukemogenesis and demonstrated the metabolic dependence of T-lymphoblasts on the TCA cycle, thus providing implications for targeted therapy.
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Search for single top-quark production via flavour-changing neutral currents at 8 TeV with the ATLAS detector. THE EUROPEAN PHYSICAL JOURNAL. C, PARTICLES AND FIELDS 2016; 76:55. [PMID: 26900343 PMCID: PMC4750458 DOI: 10.1140/epjc/s10052-016-3876-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/02/2015] [Accepted: 01/01/2016] [Indexed: 06/05/2023]
Abstract
A search for single top-quark production via flavour-changing neutral current processes from gluon plus up- or charm-quark initial states in proton-proton collisions at the LHC is presented. Data collected with the ATLAS detector in 2012 at a centre-of-mass energy of 8 TeV and corresponding to an integrated luminosity of 20.3 fb[Formula: see text] are used. Candidate events for a top quark decaying into a lepton, a neutrino and a jet are selected and classified into signal- and background-like candidates using a neural network. No signal is observed and an upper limit on the production cross-section multiplied by the [Formula: see text] branching fraction is set. The observed 95 % CL limit is [Formula: see text] and the expected 95 % CL limit is [Formula: see text]. The observed limit can be interpreted as upper limits on the coupling constants of the flavour-changing neutral current interactions divided by the scale of new physics [Formula: see text] and [Formula: see text] and on the branching fractions [Formula: see text] and [Formula: see text].
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Search for an additional, heavy Higgs boson in the [Formula: see text] decay channel at [Formula: see text] in [Formula: see text] collision data with the ATLAS detector. THE EUROPEAN PHYSICAL JOURNAL. C, PARTICLES AND FIELDS 2016; 76:45. [PMID: 26949371 PMCID: PMC4764141 DOI: 10.1140/epjc/s10052-015-3820-z] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/22/2015] [Accepted: 12/01/2015] [Indexed: 06/05/2023]
Abstract
A search is presented for a high-mass Higgs boson in the [Formula: see text], [Formula: see text], [Formula: see text], and [Formula: see text] decay modes using the ATLAS detector at the CERN Large Hadron Collider. The search uses proton-proton collision data at a centre-of-mass energy of 8 TeV corresponding to an integrated luminosity of 20.3 fb[Formula: see text]. The results of the search are interpreted in the scenario of a heavy Higgs boson with a width that is small compared with the experimental mass resolution. The Higgs boson mass range considered extends up to [Formula: see text] for all four decay modes and down to as low as 140 [Formula: see text], depending on the decay mode. No significant excess of events over the Standard Model prediction is found. A simultaneous fit to the four decay modes yields upper limits on the production cross-section of a heavy Higgs boson times the branching ratio to [Formula: see text] boson pairs. 95 % confidence level upper limits range from 0.53 pb at [Formula: see text] GeV to 0.008 pb at [Formula: see text] GeV for the gluon-fusion production mode and from 0.31 pb at [Formula: see text] GeV to 0.009 pb at [Formula: see text] GeV for the vector-boson-fusion production mode. The results are also interpreted in the context of Type-I and Type-II two-Higgs-doublet models.
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Abstract B08: Space radiation exposure induces stable epigenome alterations relevant to human lung cancer. Cancer Res 2016. [DOI: 10.1158/1538-7445.chromepi15-b08] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Manned interplanetary travel is imminent, but currently inhibited by uncertainty surrounding the long-term human health risks associated with space radiation exposure, for which there is currently no effective means of shielding. Terrestrial exposure to ionizing radiation, such as γ- or X-rays, increases the age-related risk of most common human cancers, however the extent to which these risks can be extrapolated to astronauts in deep space remains unclear. Compared to terrestrial radiation, space radiation contains high charge and energy (HZE) ions with a high linear energy transfer (high-LET). As they traverse the cell, HZE ions interact directly with macromolecules along the particle trajectory, and emit high-energy secondary electrons (δ rays) that extend laterally for several microns, resulting in a wide and densely ionizing core track. HZE radiation creates a complex mixture of DNA damage (double strand breaks, single strand breaks, oxidative base damage, etc.) in tight clusters along the particle track that can be difficult to repair. Consequently, research thus far has focused on the influence of both terrestrial and space radiation on DNA. Here we sought to determine the acute impact and long-term consequences of space radiation exposure on the epigenome. Immortalized human bronchial epithelial cells (3KT) were exposed to low LET (X-ray) or HLET radiation (28Si, 56Fe). Cells were harvested after 48hrs or maintained in continuous culture for an additional 3 months, and DNA methylation patterns using the Illumina Human 450K platform. A linear mixed-effects model was applied to identify changes in DNA methylation significantly associated with dose, source, or time after exposure. Significantly, we found that radiation-induced methylation changes occur early and persist over time, reflecting a stable and heritable change to the epigenome. CpG sites affected by high and low LET radiation exposure also tended to affect CpG sites in different genomic compartments. Fe-affected CpG sites were enriched in CpG island ‘shores’ and underrepresented in gene bodies, whereas those affected by X-ray exposure were enriched in gene bodies and intergenic regions. Interestingly, Fe affected sites tended to affect CpG sites in regions with features of ‘open’ chromatin, such as promoters and distal enhancer elements, whereas sites affected by Si were overrepresented in heterochromatic regions. To probe the significance of our findings with respect to human lung cancer, we examined the methylation status of the radiation-sensitive CpG sites in primary human lung cancers analyzed in The Cancer Genome Atlas (TCGA) project. We found that the methylation status of Fe radiation sensitive sites could discriminate tumor from normal tissue for both lung adenocarcinomas and squamous cell lung carcinomas. No such relationship existed for the sites affected by low LET X-rays or 28Si radiation exposure. Thus, the high LET radiation exposure ‘signature’ reflects a cancer-specific methylation pattern observed in human primary lung cancers. From these data, we suggest that the stable imprint of a prior high LET radiation exposure is reflected in the DNA methylation pattern, and may prove useful as a biomarker of long-term, individual cancer risk.
Citation Format: E. Kennedy, D.R. Powell, Z. Li, J.S.K. Bell, H. Feng, W. Dynan, B. Dwivedi, J. Kowalski, K.N. Conneely and P.M. Vertino. Space radiation exposure induces stable epigenome alterations relevant to human lung cancer. [abstract]. In: Proceedings of the AACR Special Conference on Chromatin and Epigenetics in Cancer; Sep 24-27, 2015; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2016;76(2 Suppl):Abstract nr B08.
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Search for flavour-changing neutral current top-quark decays to [Formula: see text] in [Formula: see text] collision data collected with the ATLAS detector at [Formula: see text] TeV. THE EUROPEAN PHYSICAL JOURNAL. C, PARTICLES AND FIELDS 2016; 76:12. [PMID: 26855606 PMCID: PMC4732594 DOI: 10.1140/epjc/s10052-015-3851-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/25/2015] [Accepted: 12/15/2015] [Indexed: 06/05/2023]
Abstract
A search for the flavour-changing neutral-current decay [Formula: see text] is presented. Data collected by the ATLAS detector during 2012 from proton-proton collisions at the Large Hadron Collider at a centre-of-mass energy of [Formula: see text] TeV, corresponding to an integrated luminosity of 20.3 fb[Formula: see text], are analysed. Top-quark pair-production events with one top quark decaying through the [Formula: see text] ([Formula: see text]) channel and the other through the dominant Standard Model mode [Formula: see text] are considered as signal. Only the decays of the Z boson to charged leptons and leptonic W boson decays are used. No evidence for a signal is found and an observed (expected) upper limit on the [Formula: see text] branching ratio of [Formula: see text] ([Formula: see text]) is set at the 95 % confidence level.
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Measurements of fiducial cross-sections for [Formula: see text] production with one or two additional b-jets in pp collisions at [Formula: see text]=8 TeV using the ATLAS detector. THE EUROPEAN PHYSICAL JOURNAL. C, PARTICLES AND FIELDS 2016; 76:11. [PMID: 26770069 PMCID: PMC4710097 DOI: 10.1140/epjc/s10052-015-3852-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/28/2015] [Accepted: 12/16/2015] [Indexed: 06/01/2023]
Abstract
Fiducial cross-sections for [Formula: see text] production with one or two additional b-jets are reported, using an integrated luminosity of 20.3 fb[Formula: see text] of proton-proton collisions at a centre-of-mass energy of 8 TeV at the Large Hadron Collider, collected with the ATLAS detector. The cross-section times branching ratio for [Formula: see text] events with at least one additional b-jet is measured to be 950 [Formula: see text] 70 (stat.) [Formula: see text] (syst.) fb in the lepton-plus-jets channel and 50 [Formula: see text] 10 (stat.) [Formula: see text] (syst.) fb in the [Formula: see text] channel. The cross-section times branching ratio for events with at least two additional b-jets is measured to be 19.3 [Formula: see text] 3.5 (stat.) [Formula: see text] 5.7 (syst.) fb in the dilepton channel ([Formula: see text], [Formula: see text], and ee) using a method based on tight selection criteria, and 13.5 [Formula: see text] 3.3 (stat.) [Formula: see text] 3.6 (syst.) fb using a looser selection that allows the background normalisation to be extracted from data. The latter method also measures a value of 1.30 [Formula: see text] 0.33 (stat.) [Formula: see text] 0.28 (syst.)% for the ratio of [Formula: see text] production with two additional b-jets to [Formula: see text] production with any two additional jets. All measurements are in good agreement with recent theory predictions.
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Searches for scalar leptoquarks in pp collisions at [Formula: see text] = 8 TeV with the ATLAS detector. THE EUROPEAN PHYSICAL JOURNAL. C, PARTICLES AND FIELDS 2016; 76:5. [PMID: 26770067 PMCID: PMC4710100 DOI: 10.1140/epjc/s10052-015-3823-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/20/2015] [Accepted: 12/01/2015] [Indexed: 06/05/2023]
Abstract
Searches for pair-produced scalar leptoquarks are performed using 20 fb[Formula: see text] of proton-proton collision data provided by the LHC and recorded by the ATLAS detector at [Formula: see text] TeV. Events with two electrons (muons) and two or more jets in the final state are used to search for first (second)-generation leptoquarks. The results from two previously published ATLAS analyses are interpreted in terms of third-generation leptoquarks decaying to [Formula: see text] and [Formula: see text] final states. No statistically significant excess above the Standard Model expectation is observed in any channel and scalar leptoquarks are excluded at 95 % CL with masses up to [Formula: see text] 1050 GeV for first-generation leptoquarks, [Formula: see text] 1000 GeV for second-generation leptoquarks, [Formula: see text] 625 GeV for third-generation leptoquarks in the [Formula: see text] channel, and 200 [Formula: see text] 640 GeV in the [Formula: see text] channel.
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