1,158 research outputs found

    A note on comonotonicity and positivity of the control components of decoupled quadratic FBSDE

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    In this small note we are concerned with the solution of Forward-Backward Stochastic Differential Equations (FBSDE) with drivers that grow quadratically in the control component (quadratic growth FBSDE or qgFBSDE). The main theorem is a comparison result that allows comparing componentwise the signs of the control processes of two different qgFBSDE. As a byproduct one obtains conditions that allow establishing the positivity of the control process.Comment: accepted for publicatio

    A high resolution, low power time-of-flight system for the space experiment AMS

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    The system of plastic scintillator counters for the AMS experiment is described. The main characteristics of the detector are: (a) large sensitive area (four 1.6 m2 planes) with small dead space; (b) low-power consumption (150 W for the power and the read-out electronics of 336 PMs); (c) 120 ps time resolution. ( 1999 Elsevier Science B.V. All rights reserved

    Transverse sphericity of primary charged particles in minimum bias proton–proton collisions at √s = 0.9, 2.76 and 7 TeV

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    Measurements of the sphericity of primary charged particles in minimum bias proton–proton collisions at s√=0.9, 2.76 and 7 TeV with the ALICE detector at the LHC are presented. The observable is measured in the plane perpendicular to the beam direction using primary charged tracks with p T>0.5 GeV/c in |η|<0.8. The mean sphericity as a function of the charged particle multiplicity at mid-rapidity (N ch) is reported for events with different p T scales (“soft” and “hard”) defined by the transverse momentum of the leading particle. In addition, the mean charged particle transverse momentum versus multiplicity is presented for the different event classes, and the sphericity distributions in bins of multiplicity are presented. The data are compared with calculations of standard Monte Carlo event generators. The transverse sphericity is found to grow with multiplicity at all collision energies, with a steeper rise at low N ch, whereas the event generators show an opposite tendency. The combined study of the sphericity and the mean p T with multiplicity indicates that most of the tested event generators produce events with higher multiplicity by generating more back-to-back jets resulting in decreased sphericity (and isotropy). The PYTHIA6 generator with tune PERUGIA-2011 exhibits a noticeable improvement in describing the data, compared to the other tested generators

    An NLO QCD analysis of inclusive cross-section and jet-production data from the ZEUS experiment

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    The ZEUS inclusive differential cross-section data from HERA, for charged and neutral current processes taken with e+ and e− beams, together with differential cross-section data on inclusive jet production in e+p scattering and dijet production in γp scattering, have been used in a new NLO QCD analysis to extract the parton distribution functions of the proton. The input of jet-production data constrains the gluon and allows an accurate extraction of αs (MZ) at NLO; αs (MZ) = 0.1183 ± 0.0028(exp.) ± 0.0008(model). An additional uncertainty from the choice of scales is estimated as ±0.005. This is the first extraction of αs (MZ) from HERA data alone

    Long-range angular correlations on the near and away side in p&#8211;Pb collisions at

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    Event-shape engineering for inclusive spectra and elliptic flow in Pb-Pb collisions at root(NN)-N-S=2.76 TeV

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    Production of He-4 and (4) in Pb-Pb collisions at root(NN)-N-S=2.76 TeV at the LHC

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    Results on the production of He-4 and (4) nuclei in Pb-Pb collisions at root(NN)-N-S = 2.76 TeV in the rapidity range vertical bar y vertical bar <1, using the ALICE detector, are presented in this paper. The rapidity densities corresponding to 0-10% central events are found to be dN/dy4(He) = (0.8 +/- 0.4 (stat) +/- 0.3 (syst)) x 10(-6) and dN/dy4 = (1.1 +/- 0.4 (stat) +/- 0.2 (syst)) x 10(-6), respectively. This is in agreement with the statistical thermal model expectation assuming the same chemical freeze-out temperature (T-chem = 156 MeV) as for light hadrons. The measured ratio of (4)/He-4 is 1.4 +/- 0.8 (stat) +/- 0.5 (syst). (C) 2018 Published by Elsevier B.V.Peer reviewe

    Underlying Event measurements in pp collisions at s=0.9 \sqrt {s} = 0.9 and 7 TeV with the ALICE experiment at the LHC

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    Erectile dysfunction in kidney transplanted patients: efficacy of sildenafil

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    BACKGROUND: Erectile dysfunction (ED) is the inability to achieve and/or maintain an erection for satisfactory sexual performance. The effects of kidney transplantation on pre-existing ED are poorly understood, as well as the onset of new ED cases after kidney transplantation. This study aimed to evaluate the effects of kidney transplantation on pre-existing ED, to assess the onset of new ED cases after renal transplantation and to assess both the efficacy and safety of sildenafil. METHODS: Erectile function was assessed using the self-administered International Index of Erectile Function (IIEF) to kidney transplanted patients. A 50 mg dose of sildenafil was prescribed. Sildenafil efficacy was assessed by re-administering the questionnaire after 4 weeks of therapy. Blood chemistry and serum cyclosporine concentration were evaluated at the beginning of the study and, in patients treated with sildenafil, after 4 weeks of treatment. RESULTS: One hundred and thirteen patients (87.5%) completed the questionnaire. Fifty-three patients (47%) did not complain of ED, the remaining 60 patients (53%) reported ED. ED was already present during dialysis in 40 patients; it appeared ex novo in 20 patients after transplantation. Pre-existing ED disappeared in 8 patients (20%), ameliorated in 13 patients (32.5%), worsened in 2 patients (5%), and remained unchanged in 17 patients (42.5%) after transplantation. The IIEF score significantly improved in sildenafil-treated patients (n=20); there were no observed changes in blood chemistry, blood pressure (BP), renal function and cyclosporine concentration. The side-effects were minimal. CONCLUSIONS: ED was still present in a large cohort of kidney transplanted men. Renal transplantation cures few ED cases. ED can appear ex novo after transplantation. Sildenafil is an effective ED treatment in kidney transplanted men
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