Outcomes of Bilateral Cataract Surgery in Infants 7 to 24 Months of Age Using the Toddler Aphakia and Pseudophakia Treatment Study Registry

Purpose To evaluate outcomes of bilateral cataract surgery in children aged 7 to 24 months and compare rates of adverse events (AEs) with other Toddler Aphakia and Pseudophakia Study (TAPS) registry outcomes. Design Retrospective clinical study at 10 Infant Aphakia Treatment Study (IATS) sites. Statistical analyses comparing this cohort with previously reported TAPS registry cohorts. Participants Children enrolled in the TAPS registry between 2004 and 2010. Methods Children underwent bilateral cataract surgery with or without intraocular lens (IOL) placement at age 7 to 24 months with 5 years of postsurgical follow-up. Main Outcome Measures Visual acuity (VA), occurrence of strabismus, AEs, and reoperations. Results A total of 40 children (76 eyes) who underwent bilateral cataract surgery with primary posterior capsulectomy were identified with a median age at cataract surgery of 11 months (7–23); 68% received a primary IOL. Recurrent visual axis opacification (VAO) occurred in 7.5% and was associated only with the use of an IOL (odds ratio, 6.10; P = 0.005). Glaucoma suspect (GS) was diagnosed in 2.5%, but no child developed glaucoma. In this bilateral cohort, AEs (8/40, 20%), including glaucoma or GS and VAO, and reoperations occurred in a similar proportion to that of the published unilateral TAPS cohort. When analyzed with children aged 1 to 7 months at bilateral surgery, the incidence of AEs and glaucoma or GS correlated strongly with age at surgery (P = 0.011/0.004) and glaucoma correlated with microcornea (P = 0.040) but not with IOL insertion (P = 0.15). Conclusions Follow-up to age 5 years after bilateral cataract surgery in children aged 7 to 24 months reveals a low rate of VAO and very rare glaucoma or GS diagnosis compared with infants with cataracts operated at < 7 months of age despite primary IOL implantation in most children in the group aged 7 to 24 months. The use of an IOL increases the risk of VAO irrespective of age at surgery

Outcomes of Bilateral Cataracts Removed in Infants 1 to 7 Months of Age Using the Toddler Aphakia and Pseudophakia Treatment Study Registry

Purpose To evaluate outcomes of bilateral cataract surgery in infants 1 to 7 months of age performed by Infant Aphakia Treatment Study (IATS) investigators during IATS recruitment and to compare them with IATS unilateral outcomes. Design Retrospective case series review at 10 IATS sites. Participants The Toddler Aphakia and Pseudophakia Study (TAPS) is a registry of children treated by surgeons who participated in the IATS. Methods Children underwent bilateral cataract surgery with or without intraocular lens (IOL) placement during IATS enrollment years 2004 through 2010. Main Outcome Measures Visual acuity (VA), strabismus, adverse events (AEs), and reoperations. Results One hundred seventy-eight eyes (96 children) were identified with a median age of 2.5 months (range, 1–7 months) at the time of cataract surgery. Forty-two eyes (24%) received primary IOL implantation. Median VA of the better-seeing eye at final study visit closest to 5 years of age with optotype VA testing was 0.35 logarithm of the minimum angle of resolution (logMAR; optotype equivalent, 20/45; range, 0.00–1.18 logMAR) in both aphakic and pseudophakic children. Corrected VA was excellent (<20/40) in 29% of better-seeing eyes, 15% of worse-seeing eyes. One percent showed poor acuity (≥20/200) in the better-seeing eye, 12% in the worse-seeing eye. Younger age at surgery and smaller (<9.5 mm) corneal diameter at surgery conferred an increased risk for glaucoma or glaucoma suspect designation (younger age: odds ratio [OR], 1.44; P = 0.037; and smaller cornea: OR, 3.95; P = 0.045). Adverse events also were associated with these 2 variables on multivariate analysis (younger age: OR, 1.36; P = 0.023; and smaller cornea: OR, 4.78; P = 0.057). Visual axis opacification was more common in pseudophakic (32%) than aphakic (8%) eyes (P = 0.009). Unplanned intraocular reoperation occurred in 28% of first enrolled eyes (including glaucoma surgery in 10%). Conclusions Visual acuity after bilateral cataract surgery in infants younger than 7 months is good, despite frequent systemic and ocular comorbidities. Although aphakia management did not affect VA outcome or AE incidence, IOL placement increased the risk of visual axis opacification. Adverse events and glaucoma correlated with a younger age at surgery and glaucoma correlated with the presence of microcornea

Measurement of χ c1 and χ c2 production with s√ = 7 TeV pp collisions at ATLAS

The prompt and non-prompt production cross-sections for the χ c1 and χ c2 charmonium states are measured in pp collisions at s√ = 7 TeV with the ATLAS detector at the LHC using 4.5 fb−1 of integrated luminosity. The χ c states are reconstructed through the radiative decay χ c → J/ψγ (with J/ψ → μ + μ −) where photons are reconstructed from γ → e + e − conversions. The production rate of the χ c2 state relative to the χ c1 state is measured for prompt and non-prompt χ c as a function of J/ψ transverse momentum. The prompt χ c cross-sections are combined with existing measurements of prompt J/ψ production to derive the fraction of prompt J/ψ produced in feed-down from χ c decays. The fractions of χ c1 and χ c2 produced in b-hadron decays are also measured

Measurement of the production of a W boson in association with a charm quark in pp collisions at √s = 7 TeV with the ATLAS detector

The production of a W boson in association with a single charm quark is studied using 4.6 fb−1 of pp collision data at s√ = 7 TeV collected with the ATLAS detector at the Large Hadron Collider. In events in which a W boson decays to an electron or muon, the charm quark is tagged either by its semileptonic decay to a muon or by the presence of a charmed meson. The integrated and differential cross sections as a function of the pseudorapidity of the lepton from the W-boson decay are measured. Results are compared to the predictions of next-to-leading-order QCD calculations obtained from various parton distribution function parameterisations. The ratio of the strange-to-down sea-quark distributions is determined to be 0.96+0.26−0.30 at Q 2 = 1.9 GeV2, which supports the hypothesis of an SU(3)-symmetric composition of the light-quark sea. Additionally, the cross-section ratio σ(W + +c¯¯)/σ(W − + c) is compared to the predictions obtained using parton distribution function parameterisations with different assumptions about the s−s¯¯¯ quark asymmetry

Search for squarks and gluinos with the ATLAS detector in final states with jets and missing transverse momentum using √s=8 TeV proton-proton collision data

A search for squarks and gluinos in final states containing high-p T jets, missing transverse momentum and no electrons or muons is presented. The data were recorded in 2012 by the ATLAS experiment in s√=8 TeV proton-proton collisions at the Large Hadron Collider, with a total integrated luminosity of 20.3 fb−1. Results are interpreted in a variety of simplified and specific supersymmetry-breaking models assuming that R-parity is conserved and that the lightest neutralino is the lightest supersymmetric particle. An exclusion limit at the 95% confidence level on the mass of the gluino is set at 1330 GeV for a simplified model incorporating only a gluino and the lightest neutralino. For a simplified model involving the strong production of first- and second-generation squarks, squark masses below 850 GeV (440 GeV) are excluded for a massless lightest neutralino, assuming mass degenerate (single light-flavour) squarks. In mSUGRA/CMSSM models with tan β = 30, A 0 = −2m 0 and μ > 0, squarks and gluinos of equal mass are excluded for masses below 1700 GeV. Additional limits are set for non-universal Higgs mass models with gaugino mediation and for simplified models involving the pair production of gluinos, each decaying to a top squark and a top quark, with the top squark decaying to a charm quark and a neutralino. These limits extend the region of supersymmetric parameter space excluded by previous searches with the ATLAS detector

Search for a CP-odd Higgs boson decaying to Zh in pp collisions at √s=8TeV with the ATLAS detector

A search for a heavy, CP-odd Higgs boson, A, decaying into a Zboson and a 125GeV Higgs boson, h, with the ATLAS detector at the LHC is presented. The search uses proton–proton collision data at a centre-of-mass energy of 8TeV corresponding to an integrated luminosity of 20.3fb−1. Decays of CP-even hbosons to ττor bbpairs with the Zboson decaying to electron or muon pairs are considered, as well as h →bbdecays with the Zboson decaying to neutrinos. No evidence for the production of an Aboson in these channels is found and the 95% confidence level upper limits derived for σ(gg→A) ×BR(A →Zh) ×BR(h →f¯f)are 0.098–0.013pb for f=τand 0.57–0.014pb for f=bin a range of mA=220–1000GeV. The results are combined and interpreted in the context of two-Higgs-doublet models. Published by Elsevier B.V. This is an open access article under the CC BY license (http://creativecommons

Search for direct production of charginos and neutralinos in events with three leptons and missing transverse momentum in √s = 8 TeV pp collisions with the ATLAS detector

A search for the direct production of charginos and neutralinos in final states with three leptons and missing transverse momentum is presented. The analysis is based on 20.3 fb−1 of s√ = 8 TeV proton-proton collision data delivered by the Large Hadron Collider and recorded with the ATLAS detector. Observations are consistent with the Standard Model expectations and limits are set in R-parity-conserving phenomenological Minimal Supersymmetric Standard Models and in simplified supersymmetric models, significantly extending previous results. For simplified supersymmetric models of direct chargino (χ˜±1) and next-to-lightest neutralino (χ˜02) production with decays to lightest neutralino (χ˜01) via either all three generations of sleptons, staus only, gauge bosons, or Higgs bosons, (χ˜±1) and (χ˜02) masses are excluded up to 700 GeV, 380 GeV, 345 GeV, or 148 GeV respectively, for a massless (χ˜01

Observation of top-quark pair production in association with a photon and measurement of the ttγ production cross section in pp collisions at √s = 7 TeV using the ATLAS detector

A search is performed for top-quark pairs (tt) produced together with a photon (γ) with transverse energy greater than 20 GeV using a sample of tt candidate events in final states with jets, missing transverse momentum, and one isolated electron or muon. The data set used corresponds to an integrated luminosity of 4.59 fb −1 of proton-proton collisions at a center-of-mass energy of 7 TeV recorded by the ATLAS detector at the CERN Large Hadron Collider. In total, 140 and 222 ttγ candidate events are observed in the electron and muon channels, to be compared to the expectation of 79 +/- 26 and 120 +/- 39 non-ttγ background events, respectively. The production of ttγ events is observed with a significance of 5.3 standard deviations away from the null hypothesis. The ttγ production cross section times the branching ratio (BR) of the single-lepton decay channel is measured in a fiducial kinematic region within the ATLAS acceptance. The measured value is σ (fid/tty) × BR = 63 +/- 8(stat) (+17/-13)(syst) +/- 1 lumi fb per lepton flavor, in good agreement with the leading-order theoretical calculation normalized to the next-to-leading-order theoretical prediction of 48 +/- 10 fb

Observation of associated near-side and away-side long-range correlations in √sNN=5.02 TeV proton-lead collisions with the ATLAS detector

Two-particle correlations in relative azimuthal angle (Δϕ) and pseudorapidity (Δη) are measured in √sNN=5.02  TeV p+Pb collisions using the ATLAS detector at the LHC. The measurements are performed using approximately 1  μb-1 of data as a function of transverse momentum (pT) and the transverse energy (ΣETPb) summed over 3.1<η<4.9 in the direction of the Pb beam. The correlation function, constructed from charged particles, exhibits a long-range (2<|Δη|<5) “near-side” (Δϕ∼0) correlation that grows rapidly with increasing ΣETPb. A long-range “away-side” (Δϕ∼π) correlation, obtained by subtracting the expected contributions from recoiling dijets and other sources estimated using events with small ΣETPb, is found to match the near-side correlation in magnitude, shape (in Δη and Δϕ) and ΣETPb dependence. The resultant Δϕ correlation is approximately symmetric about π/2, and is consistent with a dominant cos⁡2Δϕ modulation for all ΣETPb ranges and particle pT

Search for direct pair production of the top squark in all-hadronic final states in proton-proton collisions at s√=8 TeV with the ATLAS detector

The results of a search for direct pair production of the scalar partner to the top quark using an integrated luminosity of 20.1fb−1 of proton–proton collision data at √s = 8 TeV recorded with the ATLAS detector at the LHC are reported. The top squark is assumed to decay via t˜→tχ˜01 or t˜→ bχ˜±1 →bW(∗)χ˜01 , where χ˜01 (χ˜±1 ) denotes the lightest neutralino (chargino) in supersymmetric models. The search targets a fully-hadronic final state in events with four or more jets and large missing transverse momentum. No significant excess over the Standard Model background prediction is observed, and exclusion limits are reported in terms of the top squark and neutralino masses and as a function of the branching fraction of t˜ → tχ˜01 . For a branching fraction of 100%, top squark masses in the range 270–645 GeV are excluded for χ˜01 masses below 30 GeV. For a branching fraction of 50% to either t˜ → tχ˜01 or t˜ → bχ˜±1 , and assuming the χ˜±1 mass to be twice the χ˜01 mass, top squark masses in the range 250–550 GeV are excluded for χ˜01 masses below 60 GeV