136 research outputs found

    Application of the Two-Scale Model to the HERMES Data on Nuclear Attenuation

    Full text link
    The Two-Scale Model and its improved version were used to perform the fit to the HERMES data for ν\nu (the virtual photon energy) and z (the fraction of ν\nu carried by hadron) dependencies of nuclear multiplicity ratios for π+\pi^+ and π\pi^- mesons electro-produced on two nuclear targets (14^{14}N and 84^{84}Kr). The quantitative criterium χ2\chi ^2 was used for the first time to analyse the results of the model fit to the nuclear multiplicity ratios data. The two-parameter's fit gives satisfactory agreement with the HERMES data. Best values of the parameters were then used to calculate the ν\nu- and zz - dependencies of nuclear attenuation for π0\pi^0, K+^+, K^- and pˉ\bar{p} produced on 84^{84}Kr target, and also make a predictions for ν\nu, z and the Q2^2 (the photon virtuality) - dependencies of nuclear attenuation data for those identified hadrons and nuclea, that will be published by HERMES

    Correction to: First results on survival from a large Phase 3 clinical trial of an autologous dendritic cell vaccine in newly diagnosed glioblastoma

    Get PDF
    © 2018 The Author(s). Following publication of the original article [1], the authors reported an error in the spelling of one of the author names. In this Correction the incorrect and correct author names are indicated and the author name has been updated in the original publication. The authors also reported an error in the Methods section of the original article. In this Correction the incorrect and correct versions of the affected sentence are indicated. The original article has not been updated with regards to the error in the Methods section

    Understanding edge-connectivity in the Internet through core-decomposition

    Get PDF
    Internet is a complex network composed by several networks: the Autonomous Systems, each one designed to transport information efficiently. Routing protocols aim to find paths between nodes whenever it is possible (i.e., the network is not partitioned), or to find paths verifying specific constraints (e.g., a certain QoS is required). As connectivity is a measure related to both of them (partitions and selected paths) this work provides a formal lower bound to it based on core-decomposition, under certain conditions, and low complexity algorithms to find it. We apply them to analyze maps obtained from the prominent Internet mapping projects, using the LaNet-vi open-source software for its visualization

    Elliptic flow of charged particles in Pb-Pb collisions at 2.76 TeV

    Get PDF
    We report the first measurement of charged particle elliptic flow in Pb-Pb collisions at 2.76 TeV with the ALICE detector at the CERN Large Hadron Collider. The measurement is performed in the central pseudorapidity region (|η\eta|<0.8) and transverse momentum range 0.2< pTp_{\rm T}< 5.0 GeV/cc. The elliptic flow signal v2_2, measured using the 4-particle correlation method, averaged over transverse momentum and pseudorapidity is 0.087 ±\pm 0.002 (stat) ±\pm 0.004 (syst) in the 40-50% centrality class. The differential elliptic flow v2(pT)_2(p_{\rm T}) reaches a maximum of 0.2 near pTp_{\rm T} = 3 GeV/cc. Compared to RHIC Au-Au collisions at 200 GeV, the elliptic flow increases by about 30%. Some hydrodynamic model predictions which include viscous corrections are in agreement with the observed increase.Comment: 10 pages, 4 captioned figures, published version, figures at http://aliceinfo.cern.ch/ArtSubmission/node/389

    Evidence for an Excess of Soft Photons in Hadronic Decays of Z^0

    Full text link
    Soft photons inside hadronic jets converted in front of the DELPHI main tracker (TPC) in events of qqbar disintegrations of the Z^0 were studied in the kinematic range 0.2 < E_gamma < 1 GeV and transverse momentum with respect to the closest jet direction p_T < 80 MeV/c. A clear excess of photons in the experimental data as compared to the Monte Carlo predictions is observed. This excess (uncorrected for the photon detection efficiency) is (1.17 +/- 0.06 +/- 0.27) x 10^{-3} gamma/jet in the specified kinematic region, while the expected level of the inner hadronic bremsstrahlung (which is not included in the Monte Carlo) is (0.340 +/- 0.001 +/- 0.038) x 10^{-3} gamma/jet. The ratio of the excess to the predicted bremsstrahlung rate is then (3.4 +/- 0.2 +/- 0.8), which is similar in strength to the anomalous soft photon signal observed in fixed target experiments with hadronic beams.Comment: 37 pages, 9 figures, Accepted by Eur. Phys. J.

    The three pillars of institutional theory and IFRS implementation in Nigeria

    Get PDF
    This study explores the effects of the three pillars of institutional theory in shaping the activities of institutional entrepreneurs and other social actors during IFRS implementation in Nigeria. This study uses document analysis method to achieve the objectives of the study. This study finds that IFRS implementation in Nigeria witnessed some progression from regulative to normative to cognitive pillar building. The regulation on IFRS implementation was initiated top-down rather than through lobbying from professional accounting bodies and the public. Changes in the regulatory framework brought some improvement to corporate financial reporting practices such as the timing of corporate filings of audited financial reports. However, the implementation process is laden with conflicts and power struggle among institutional actors. These conflicts and power struggles led the President of Nigeria to sack the Board of the Financial Reporting Council of Nigeria (FRC), the reconstitution of the Board and appointment of a Chairman for the Board of the FRC. IFRS implementation process resulted in power redistribution among institutional actors, which led to resistance, tensions, and conflicts among institutional actors. The conflicts arise from the need of actors to legitimate their activities and secure their positions. The three institutional pillars are key components of a change process and the actor’s social position affects their capability to act as an institutional entrepreneur. This finding should provide foundational knowledge that will inform practitioners, researchers, and regulators in developing countries on how institutional actors shape the approach to corporate reporting regulations

    Measurement of D+- and D0 production in deep inelastic scattering using a lifetime tag at HERA

    Get PDF
    The production of D-+/-- and D-0-mesons has been measured with the ZEUS detector at HERA using an integrated luminosity of 133.6 pb(-1). The measurements cover the kinematic range 5 < Q(2) < 1000 GeV2, 0.02 < y < 0.7, 1.5 < p(T)(D) < 15 GeV and |eta(D)| < 1.6. Combinatorial background to the D-meson signals is reduced by using the ZEUS microvertex detector to reconstruct displaced secondary vertices. Production cross sections are compared with the predictions of next-to-leading-order QCD, which is found to describe the data well. Measurements are extrapolated to the full kinematic phase space in order to obtain the open-charm contribution, F-2(c (c) over bar), to the proton structure function, F-2

    The biological effects of diagnostic cardiac imaging on chronically exposed physicians: the importance of being non-ionizing

    Get PDF
    Ultrasounds and ionizing radiation are extensively used for diagnostic applications in the cardiology clinical practice. This paper reviewed the available information on occupational risk of the cardiologists who perform, every day, cardiac imaging procedures. At the moment, there are no consistent evidence that exposure to medical ultrasound is capable of inducing genetic effects, and representing a serious health hazard for clinical staff. In contrast, exposure to ionizing radiation may result in adverse health effect on clinical cardiologists. Although the current risk estimates are clouded by approximations and extrapolations, most data from cytogenetic studies have reported a detrimental effect on somatic DNA of professionally exposed personnel to chronic low doses of ionizing radiation. Since interventional cardiologists and electro-physiologists have the highest radiation exposure among health professionals, a major awareness is crucial for improving occupational protection. Furthermore, the use of a biological dosimeter could be a reliable tool for the risk quantification on an individual basis
    corecore