2,263 research outputs found

    A Case of Ciliary Body Melanocytoma Presenting as a Painful Iris Mass

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    We report a case of ciliary body melanocytoma in a Korean patient, which presented as an intermittently painful pigmented iris mass and was successfully managed by iridocyclectomy. A 52-year-old healthy man presented with an irregularly-shaped and heavily-pigmented mass at the iris root of his right eye. Visual acuity of the right eye was 20/20 with normal intraocular pressure. Ultrasound biomicroscopy showed a 1.5x1.3-mm ciliary-body mass with extension into the iris root. Iridocyclectomy with scleral resection under a lamellar scleral flap was performed, and the histopathologic features of the resected tissue were consistent with melanocytoma of the ciliary body. The patient's visual acuity remained 20/20 with good postoperative cosmesis. During one year of follow-up, no signs of tumor recurrence were seen, and the patient reported resolution of the intermittent ocular pain in the involved eye

    A Novel BEST1 Mutation in Autosomal Recessive Bestrophinopathy

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    Citation: Lee CS, Jun I, Choi S, et al. A novel BEST1 mutation in autosomal recessive bestrophinopathy. Invest Ophthalmol Vis Sci. 2015;56:8141-8150. DOI:10.1167/iovs.15-18168 PURPOSE. To describe the clinical characteristics associated with a newly identified mutant of autosomal recessive bestrophinopathy (ARB) and confirm the associated physiological functional defects. METHODS. Two patients with ARB from one family underwent a full ophthalmic examination, including dilated fundus examination, fundus photography, fluorescein angiography, fundus autofluorescence imaging, spectral-domain optical coherence tomography (OCT), electroretinography (ERG), and electrooculography (EOG). Subsequently, genetic analysis for bestrophin-1 (BEST1) mutations was conducted through direct Sanger sequencing. The effect of ARB-associated mutations of BEST1 on the cellular localization was determined by in vitro experiments. Whole-cell patch clamping was conducted to measure the chloride conductance of wild-type BEST1 and the identified BEST1 mutants in transfected HEK293T cells. RESULTS. Two related patients (66-year-old brother and 52-year-old sister) presented with reduced visual acuity and bilateral symmetrical subretinal deposits of hyperautofluorescent materials in the posterior pole. Spectral-domain OCT showed macular thinning with submacular fluid. The female patient had a concomitant macular edema associated with branched retinal vein occlusion in the left eye, which responded well to intravitreal bevacizumab injections. Genetic analysis demonstrated that both patients were compound heterozygous for one novel (Leu40Pro) and one previously identified (Ala195Val) BEST1 variant. HEK293T cells transfected with the identified BEST1 mutant showed significantly small currents compared to those transfected with the wild-type gene, whereas cells cotransfected with mutant and wild-type BEST1 showed good chloride conductance. Cellular localization of BEST1 was well conserved to the plasma membrane in the mutants. CONCLUSIONS. We have identified and described the phenotype and in vitro functional aspects of a new BEST1 mutation causing ARB. Clinically suspected ARB cases warrant genetic confirmation to confirm the diagnosis

    Measurements of the pp → ZZ production cross section and the Z → 4ℓ branching fraction, and constraints on anomalous triple gauge couplings at √s = 13 TeV

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    Four-lepton production in proton-proton collisions, pp -> (Z/gamma*)(Z/gamma*) -> 4l, where l = e or mu, is studied at a center-of-mass energy of 13 TeV with the CMS detector at the LHC. The data sample corresponds to an integrated luminosity of 35.9 fb(-1). The ZZ production cross section, sigma(pp -> ZZ) = 17.2 +/- 0.5 (stat) +/- 0.7 (syst) +/- 0.4 (theo) +/- 0.4 (lumi) pb, measured using events with two opposite-sign, same-flavor lepton pairs produced in the mass region 60 4l) = 4.83(-0.22)(+0.23) (stat)(-0.29)(+0.32) (syst) +/- 0.08 (theo) +/- 0.12(lumi) x 10(-6) for events with a four-lepton invariant mass in the range 80 4GeV for all opposite-sign, same-flavor lepton pairs. The results agree with standard model predictions. The invariant mass distribution of the four-lepton system is used to set limits on anomalous ZZZ and ZZ. couplings at 95% confidence level: -0.0012 < f(4)(Z) < 0.0010, -0.0010 < f(5)(Z) < 0.0013, -0.0012 < f(4)(gamma) < 0.0013, -0.0012 < f(5)(gamma) < 0.0013

    Observation of γγ → ττ in proton-proton collisions and limits on the anomalous electromagnetic moments of the τ lepton

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    The production of a pair of τ leptons via photon–photon fusion, γγ → ττ, is observed for the f irst time in proton–proton collisions, with a significance of 5.3 standard deviations. This observation is based on a data set recorded with the CMS detector at the LHC at a center-of-mass energy of 13 TeV and corresponding to an integrated luminosity of 138 fb−1. Events with a pair of τ leptons produced via photon–photon fusion are selected by requiring them to be back-to-back in the azimuthal direction and to have a minimum number of charged hadrons associated with their production vertex. The τ leptons are reconstructed in their leptonic and hadronic decay modes. The measured fiducial cross section of γγ → ττ is σfid obs = 12.4+3.8 −3.1 fb. Constraints are set on the contributions to the anomalous magnetic moment (aτ) and electric dipole moments (dτ) of the τ lepton originating from potential effects of new physics on the γττ vertex: aτ = 0.0009+0.0032 −0.0031 and |dτ| &lt; 2.9×10−17ecm (95% confidence level), consistent with the standard model

    Development and validation of HERWIG 7 tunes from CMS underlying-event measurements

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    This paper presents new sets of parameters (“tunes”) for the underlying-event model of the HERWIG7 event generator. These parameters control the description of multiple-parton interactions (MPI) and colour reconnection in HERWIG7, and are obtained from a fit to minimum-bias data collected by the CMS experiment at s=0.9, 7, and 13Te. The tunes are based on the NNPDF 3.1 next-to-next-to-leading-order parton distribution function (PDF) set for the parton shower, and either a leading-order or next-to-next-to-leading-order PDF set for the simulation of MPI and the beam remnants. Predictions utilizing the tunes are produced for event shape observables in electron-positron collisions, and for minimum-bias, inclusive jet, top quark pair, and Z and W boson events in proton-proton collisions, and are compared with data. Each of the new tunes describes the data at a reasonable level, and the tunes using a leading-order PDF for the simulation of MPI provide the best description of the dat

    Measurement of the azimuthal anisotropy of Y(1S) and Y(2S) mesons in PbPb collisions at root s(NN)=5.02 TeV

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    The second-order Fourier coefficients (v(2)) characterizing the azimuthal distributions of Y(1S) and Y(2S) mesons produced in PbPb collisions at root s(NN) = 5.02 TeV are studied. The Y mesons are reconstructed in their dimuon decay channel, as measured by the CMS detector. The collected data set corresponds to an integrated luminosity of 1.7 nb(-1). The scalar product method is used to extract the v2 coefficients of the azimuthal distributions. Results are reported for the rapidity range vertical bar y vertical bar < 2.4, in the transverse momentum interval 0 < pT < 50 GeV/c, and in three centrality ranges of 10-30%, 30-50% and 50-90%. In contrast to the J/psi mesons, the measured v(2) values for the Y mesons are found to be consistent with zero. (C) 2021 The Author(s). Published by Elsevier B.V.Peer reviewe

    Electroweak production of two jets in association with a Z boson in proton-proton collisions root s =13 TeV

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    A measurement of the electroweak (EW) production of two jets in association with a Z boson in proton-proton collisions at root s = 13 TeV is presented, based on data recorded in 2016 by the CMS experiment at the LHC corresponding to an integrated luminosity of 35.9 fb(-1). The measurement is performed in the lljj final state with l including electrons and muons, and the jets j corresponding to the quarks produced in the hard interaction. The measured cross section in a kinematic region defined by invariant masses m(ll) > 50 GeV, m(jj) > 120 GeV, and transverse momenta P-Tj > 25 GeV is sigma(EW) (lljj) = 534 +/- 20 (stat) fb (syst) fb, in agreement with leading-order standard model predictions. The final state is also used to perform a search for anomalous trilinear gauge couplings. No evidence is found and limits on anomalous trilinear gauge couplings associated with dimension-six operators are given in the framework of an effective field theory. The corresponding 95% confidence level intervals are -2.6 <cwww/Lambda(2) <2.6 TeV-2 and -8.4 <cw/Lambda(2) <10.1 TeV-2. The additional jet activity of events in a signal-enriched region is also studied, and the measurements are in agreement with predictions.Peer reviewe
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