4,263 research outputs found

    Femtosecond Laser-Assisted In Situ Keratomileusis Treatment of Residual Refractive Error following Femtosecond Laser-Enabled Keratoplasty.

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    Purpose:To evaluate the safety and effectiveness of femtosecond laser-assisted in situ keratomileusis (LASIK) in the treatment of residual myopia and astigmatism following femtosecond laser-enabled keratoplasty (FLEK). Design:Retrospective case review. Methods:Chart review of all patients with prior FLEK who subsequently underwent femto-LASIK surgery after full suture removal was performed at the Gavin Herbert Eye Institute at the University of California, Irvine. A total of 14 eyes in 13 patients met this criterion, and their comprehensive examinations performed at standard intervals were reviewed. Main outcome measures include uncorrected distance visual acuity (UDVA) and corrected distance visual acuity (CDVA) expressed as the logarithm of the minimum angle of resolution (logMAR), manifest refractive astigmatism, and spherical equivalent. Results:From the preoperative visit to the 3 month visit, all 14 eyes significantly improved in UDVA (logMAR, 0.93 ± 0.23 to 0.44 ± 0.32, P = 0.002) with no loss of CDVA (logMAR, 0.26 ± 0.19 to 0.18 ± 0.23, P = 0.50). All 14 eyes showed significant improvement in manifest refractive astigmatism (4.71 ± 1.77 to 2.18 ± 1.45 diopters (D), P = 0.003) and spherical equivalent (-2.57 ± 2.45 to -0.48 ± 0.83 D, P = 0.0007). There were no flap or graft complications as a result of femto-LASIK. Conclusions:Our findings suggest that femto-LASIK on eyes with prior FLEK is safe and effective in improving visual acuity and reducing residual astigmatism

    Gestión en el Área Financiera de la empresa La Rioja Consulting Corp. en el municipio de Matagalpa en el I semestre del año 2014

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    Para efectuar el presente trabajo de Seminario de Graduación se planteó la temática sobre la Gestión en el Área Financiera de la empresa La Rioja Consulting Corp. en el municipio de Matagalpa en el I semestre del año 2014. El propósito es evaluar la Gestión en el Área Financiera de la empresa La Rioja Consulting Corp. para realizar un análisis cualitativo en algunas áreas de la organización. Es importante abordar el tema de la Gestión en el Área Financiera de la empresa La Rioja Consulting Corp. ya que es una empresa en crecimiento y a medida que esta crece las operaciones aumentan y se ven limitada debido a que el personal desconoce la misión y visión de la empresa, limitándoles información acerca de los objetivos y metas que se esperan cumplir en la empresa. También requieren de más personal capacitado en cuanto a la dirección como especialistas financieros, contadores, auditores y otros; para una mejor organización en sus gestiones financieras. Podemos concluir que en La Rioja Consulting Corp. se ha llevado a cabo la Gestión financiera de una forma empírica debido a la falta de un organigrama y manual de funciones desactualizado, lo que ha dado lugar a una duplicidad de tareas y falta de asignación de responsabilidades lo que permite que la empresa no esté bien organizada y el proceso se haga más lento; se ha procurado cumplir cada uno de los objetivos de la empresa resolviendo cada una de las necesidades de la misma. El tener buenas relaciones con personas extranjeras les ha permitido vender su café a un mejor precio sin que los afectara la caída del precio del café debido a la Roya que afecto las plantaciones de café a nivel naciona

    Synthetic three-dimensional atomic structures assembled atom by atom

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    We demonstrate the realization of large, fully loaded, arbitrarily-shaped three-dimensional arrays of single atoms. Using holographic methods and real-time, atom-by-atom, plane-by-plane assembly, we engineer atomic structures with up to 72 atoms separated by distances of a few micrometres. Our method allows for high average filling fractions and the unique possibility to obtain defect-free arrays with high repetition rates. These results find immediate application for the quantum simulation of spin Hamiltonians using Rydberg atoms in state-of-the-art platforms, and are very promising for quantum-information processing with neutral atoms.Comment: 5 pages, 3 figure

    News discourse and readers’ comments: expanding the range of citizenship positions?

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    First Published May 15, 2017.Little attention has been paid to the relation between citizens’ representation in news media and citizen participation in readers’ comments, and to the roles both discourses may play in fostering public engagement in official consultation processes. This article offers a discursive analysis of these questions by focusing on how commenters, through their uses of language in connection with news texts, address the political ordering of news discourse and their positioning therein. Using Critical Discourse Analysis and other interaction-oriented forms of discourse analysis, we examine, first, the topics and the framing of voices in news coverage and, second, the interactional order, stance markers and style features of readers’ comments. Based on data regarding a policy plan on hydroelectric power in Portugal that was submitted to public consultation, we show that citizen positionings emerging from the interaction between news texts and comments change the balance of power within the discussion, but their participatory potential is restrained by traditional citizenship regimes.The author(s) disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: This work was developed for the project COMPOLIS: 'Communication and Political Engagement with Environmental Issues' and supported by the Fundacao para a Ciencia e a Tecnologia (Portugal) [grant number EXPL/IVC-COM/1717/2012] through national funds (PIDDAC) and co-funded by the European Fund of Regional Development (FEDER) through COMPETE - Operational Program Competitive Factors (POFC).info:eu-repo/semantics/publishedVersio

    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

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    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

    Measurement of the inclusive and dijet cross-sections of b-jets in pp collisions at sqrt(s) = 7 TeV with the ATLAS detector

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    The inclusive and dijet production cross-sections have been measured for jets containing b-hadrons (b-jets) in proton-proton collisions at a centre-of-mass energy of sqrt(s) = 7 TeV, using the ATLAS detector at the LHC. The measurements use data corresponding to an integrated luminosity of 34 pb^-1. The b-jets are identified using either a lifetime-based method, where secondary decay vertices of b-hadrons in jets are reconstructed using information from the tracking detectors, or a muon-based method where the presence of a muon is used to identify semileptonic decays of b-hadrons inside jets. The inclusive b-jet cross-section is measured as a function of transverse momentum in the range 20 < pT < 400 GeV and rapidity in the range |y| < 2.1. The bbbar-dijet cross-section is measured as a function of the dijet invariant mass in the range 110 < m_jj < 760 GeV, the azimuthal angle difference between the two jets and the angular variable chi in two dijet mass regions. The results are compared with next-to-leading-order QCD predictions. Good agreement is observed between the measured cross-sections and the predictions obtained using POWHEG + Pythia. MC@NLO + Herwig shows good agreement with the measured bbbar-dijet cross-section. However, it does not reproduce the measured inclusive cross-section well, particularly for central b-jets with large transverse momenta.Comment: 10 pages plus author list (21 pages total), 8 figures, 1 table, final version published in European Physical Journal

    Measurement of the cross-section and charge asymmetry of WW bosons produced in proton-proton collisions at s=8\sqrt{s}=8 TeV with the ATLAS detector

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    This paper presents measurements of the W+μ+νW^+ \rightarrow \mu^+\nu and WμνW^- \rightarrow \mu^-\nu cross-sections and the associated charge asymmetry as a function of the absolute pseudorapidity of the decay muon. The data were collected in proton--proton collisions at a centre-of-mass energy of 8 TeV with the ATLAS experiment at the LHC and correspond to a total integrated luminosity of 20.2~\mbox{fb^{-1}}. The precision of the cross-section measurements varies between 0.8% to 1.5% as a function of the pseudorapidity, excluding the 1.9% uncertainty on the integrated luminosity. The charge asymmetry is measured with an uncertainty between 0.002 and 0.003. The results are compared with predictions based on next-to-next-to-leading-order calculations with various parton distribution functions and have the sensitivity to discriminate between them.Comment: 38 pages in total, author list starting page 22, 5 figures, 4 tables, submitted to EPJC. All figures including auxiliary figures are available at https://atlas.web.cern.ch/Atlas/GROUPS/PHYSICS/PAPERS/STDM-2017-13

    Search for direct production of charginos and neutralinos in events with three leptons and missing transverse momentum in √s = 7 TeV pp collisions with the ATLAS detector

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    A search for the direct production of charginos and neutralinos in final states with three electrons or muons and missing transverse momentum is presented. The analysis is based on 4.7 fb−1 of proton–proton collision data delivered by the Large Hadron Collider and recorded with the ATLAS detector. Observations are consistent with Standard Model expectations in three signal regions that are either depleted or enriched in Z-boson decays. Upper limits at 95% confidence level are set in R-parity conserving phenomenological minimal supersymmetric models and in simplified models, significantly extending previous results

    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

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    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

    Inclusive search for same-sign dilepton signatures in pp collisions at root s=7 TeV with the ATLAS detector

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    An inclusive search is presented for new physics in events with two isolated leptons (e or mu) having the same electric charge. The data are selected from events collected from p p collisions at root s = 7 TeV by the ATLAS detector and correspond to an integrated luminosity of 34 pb(-1). The spectra in dilepton invariant mass, missing transverse momentum and jet multiplicity are presented and compared to Standard Model predictions. In this event sample, no evidence is found for contributions beyond those of the Standard Model. Limits are set on the cross-section in a fiducial region for new sources of same-sign high-mass dilepton events in the ee, e mu and mu mu channels. Four models predicting same-sign dilepton signals are constrained: two descriptions of Majorana neutrinos, a cascade topology similar to supersymmetry or universal extra dimensions, and fourth generation d-type quarks. Assuming a new physics scale of 1 TeV, Majorana neutrinos produced by an effective operator V with masses below 460 GeV are excluded at 95% confidence level. A lower limit of 290 GeV is set at 95% confidence level on the mass of fourth generation d-type quarks
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