239 research outputs found

    Coarctation of the aorta in infants under one year of age

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    During the 10-year period 1962 - 1971, coarctation of the aorta was diagnosed within the first 5 months of life in 35 hospital cases. Of these, 29 (83%) were symptomatic, and 18 (54%) underwent surgery to correct the coarctation. Thirteen of the 18 patients (72%) survived the procedure. Of the 5 patients who died, 2 had single-ventricle complexes, and 1 had an associated ventricular septal defect and died at a subsequent operation for pulmonary artery banding. One patient who survived had a thoracotomy with no procedure done to the aorta.All survivors were followed up for at least 1 year. Residual gradients were found in 6 of the 12 patients (50%), but classified as severe in only 2 cases.Of the 11 patients who were symptomatic but who did not undergo surgery, 7 died (mortality 63%). There were 6 remaining patients who were asymptomatic. There have been 3 deaths in this series-all unrelated to their cardiac pathology.It is strongly recommended that young babies with coarctation of the aorta, who develop congestive cardiac failure, undergo 36 - 48 hours of medical therapy, after which surgical resection of the coiucted segment is carried out. This approach offers the best prospects for survival.S. Afr. Med. J, 48, 397 (1974)

    SPIRAL2 cryomodule production result and analyses

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    THIOB02International audienceThe production and qualification of the SPIRAL2 cryomodules are close to the end. Their performances arenow well established. This paper will explain the path followed to the good achievements, and show somestatistical analyses to be used for future projects. How far can we push the performances? What cryogenicsconsumption shall we take as design values

    Realistic Model of the Nucleon Spectral Function in Few- and Many- Nucleon Systems

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    By analysing the high momentum features of the nucleon momentum distribution in light and complex nuclei, it is argued that the basic two-nucleon configurations generating the structure of the nucleon Spectral Function at high values of the nucleon momentum and removal energy, can be properly described by a factorised ansatz for the nuclear wave function, which leads to a nucleon Spectral Function in the form of a convolution integral involving the momentum distributions describing the relative and center-of-mass motion of a correlated nucleon-nucleon pair embedded in the medium. The Spectral Functions of 3He^3He and infinite nuclear matter resulting from the convolution formula and from many-body calculations are compared, and a very good agreement in a wide range of values of nucleon momentum and removal energy is found. Applications of the model to the analysis of inclusive and exclusive processes are presented, illustrating those features of the cross section which are sensitive to that part of the Spectral Function which is governed by short-range and tensor nucleon-nucleon correlations.Comment: 40 pages Latex , 16 ps figures available from the above e-mail address or from [email protected]

    Virtual Compton Scattering and Neutral Pion Electroproduction in the Resonance Region up to the Deep Inelastic Region at Backward Angles

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    We have made the first measurements of the virtual Compton scattering (VCS) process via the H(e,ep)γ(e,e'p)\gamma exclusive reaction in the nucleon resonance region, at backward angles. Results are presented for the WW-dependence at fixed Q2=1Q^2=1 GeV2^2, and for the Q2Q^2-dependence at fixed WW near 1.5 GeV. The VCS data show resonant structures in the first and second resonance regions. The observed Q2Q^2-dependence is smooth. The measured ratio of H(e,ep)γ(e,e'p)\gamma to H(e,ep)π0(e,e'p)\pi^0 cross sections emphasizes the different sensitivity of these two reactions to the various nucleon resonances. Finally, when compared to Real Compton Scattering (RCS) at high energy and large angles, our VCS data at the highest WW (1.8-1.9 GeV) show a striking Q2Q^2- independence, which may suggest a transition to a perturbative scattering mechanism at the quark level.Comment: 20 pages, 8 figures. To appear in Phys.Rev.

    Observation of a new chi_b state in radiative transitions to Upsilon(1S) and Upsilon(2S) at ATLAS

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    The chi_b(nP) quarkonium states are produced in proton-proton collisions at the Large Hadron Collider (LHC) at sqrt(s) = 7 TeV and recorded by the ATLAS detector. Using a data sample corresponding to an integrated luminosity of 4.4 fb^-1, these states are reconstructed through their radiative decays to Upsilon(1S,2S) with Upsilon->mu+mu-. In addition to the mass peaks corresponding to the decay modes chi_b(1P,2P)->Upsilon(1S)gamma, a new structure centered at a mass of 10.530+/-0.005 (stat.)+/-0.009 (syst.) GeV is also observed, in both the Upsilon(1S)gamma and Upsilon(2S)gamma decay modes. This is interpreted as the chi_b(3P) system.Comment: 5 pages plus author list (18 pages total), 2 figures, 1 table, corrected author list, matches final version in Physical Review Letter

    Search for displaced vertices arising from decays of new heavy particles in 7 TeV pp collisions at ATLAS

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    We present the results of a search for new, heavy particles that decay at a significant distance from their production point into a final state containing charged hadrons in association with a high-momentum muon. The search is conducted in a pp-collision data sample with a center-of-mass energy of 7 TeV and an integrated luminosity of 33 pb^-1 collected in 2010 by the ATLAS detector operating at the Large Hadron Collider. Production of such particles is expected in various scenarios of physics beyond the standard model. We observe no signal and place limits on the production cross-section of supersymmetric particles in an R-parity-violating scenario as a function of the neutralino lifetime. Limits are presented for different squark and neutralino masses, enabling extension of the limits to a variety of other models.Comment: 8 pages plus author list (20 pages total), 8 figures, 1 table, final version to appear in Physics Letters

    Reducing heterotic M-theory to five dimensional supergravity on a manifold with boundary

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    This paper constructs the reduction of heterotic MM-theory in eleven dimensions to a supergravity model on a manifold with boundary in five dimensions using a Calabi-Yau three-fold. New results are presented for the boundary terms in the action and for the boundary conditions on the bulk fields. Some general features of dualisation on a manifold with boundary are used to explain the origin of some topological terms in the action. The effect of gaugino condensation on the fermion boundary conditions leads to a `twist' in the chirality of the gravitino which can provide an uplifting mechanism in the vacuum energy to cancel the cosmological constant after moduli stabilisation.Comment: 16 pages, RevTe

    Measurement of the inclusive isolated prompt photon cross-section in pp collisions at sqrt(s)= 7 TeV using 35 pb-1 of ATLAS data

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    A measurement of the differential cross-section for the inclusive production of isolated prompt photons in pp collisions at a center-of-mass energy sqrt(s) = 7 TeV is presented. The measurement covers the pseudorapidity ranges |eta|<1.37 and 1.52<=|eta|<2.37 in the transverse energy range 45<=E_T<400GeV. The results are based on an integrated luminosity of 35 pb-1, collected with the ATLAS detector at the LHC. The yields of the signal photons are measured using a data-driven technique, based on the observed distribution of the hadronic energy in a narrow cone around the photon candidate and the photon selection criteria. The results are compared with next-to-leading order perturbative QCD calculations and found to be in good agreement over four orders of magnitude in cross-section.Comment: 7 pages plus author list (18 pages total), 2 figures, 4 tables, final version published in Physics Letters
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