391 research outputs found

    Influence of Hydrogen and Low Temperature on Pipeline Steels Mechanical Behaviour

    Get PDF
    Abstract In the presence of H2S, metallic materials, such as carbon and low alloy steels, may suffer hydrogen damage and hydrogen embrittlement. Gas transporting pipes in low temperature environment, during the shutdown and the subsequent re-starting operations, are exposed to very low temperatures (T=-40 °C). In the presence of high H2S content in the gas, the risk of brittle failure can be increased due to the effect of hydrogen on steel toughness. In this paper the influence of hydrogen and low temperature on mechanical properties of two pipeline materials, F22 low alloy and X65 micro-alloyed steels, is studied. Steels have been hydrogen charged by means of an electrochemical method: diffusible hydrogen content of steels is in the range 0.6 to 2 ppm. Charpy and J-R curves tests were carried out in the range from room temperature to T=-120 °C. Hydrogen affects mechanical properties of the tested materials, mainly reducing fracture toughness in J integral tests, while little influence has been observed in CV tests. Fracture surface examination confirms the results of mechanical testing

    Expanding the phenotypic and genetic spectrum of radioulnar synostosis associated hematological disease.

    Get PDF
    Medical Research Council, Children with Cancer and Bloodwise

    Enfermedad de Gaucher en Argentina: un informe del Registro Internacional de Gaucher y del Grupo Argentino de Diagnóstico y Tratamiento de la Enfermedad de Gaucher

    Get PDF
    La Enfermedad de Gaucher por su baja frecuencia está incluida dentro de las enfermedades huérfanas. En 1991 comenzó el ingreso de pacientes en el Registro Internacional de Gaucher. En 1992 se incorporaron los primeros dos pacientes de Latinoamérica. En 2006 se creó el Grupo Argentino de Diagnóstico y Tratamiento de la Enfermedad de Gaucher siendo sus objetivos principales el entendimiento de la prevalencia, presentación, manejo y tratamiento de la Enfermedad de Gaucher en Argentina. Hasta el 1 de febrero del 2013 ingresaron al Registro Internacional 5.986 pacientes provenientes de 60 países, de los cuales 133 (2.22%) fueron argentinos. El análisis de esta publicación fue realizado sobre 133 pacientes con Enfermedad de Gaucher. Esta es la primera publicación del Grupo Argentino de Diagnóstico y Tratamiento en base a los datos del Registro Internacional. La casuística argentina mostró un predominio femenino y la forma clínica más frecuente fue el tipo 1 (97.7%, n=128). El genotipo fue identificado en 57 pacientes (42.9%), siendo el más frecuente el N370S/ otro alelo (82.5%). Entre los pacientes con datos reportados, los síntomas basales predominantes, previos al inicio del tratamiento con Imiglucerasa que predominaron fueron la esplenomegalia (100%, n=13) y la hepatomegalia (88.9%, n=8) y como citopenias más frecuentes, la trombocitopenia (64.2%, n=34) y la anemia (45.9%, n=28). La infiltración de la médula ósea como un marcador específico de enfermedad ósea se encontró en el 50% de los pacientes. En total, el 85.7% de los pacientes argentinos reciben terapia de reemplazo enzimático con Imiglucerasa, lográndose las metas terapéuticas, en la mayoría de los casos, en la última evaluación. Las metas terapéuticas más frecuentemente alcanzadas resultaron: el control de las manifestaciones óseas (dolor óseo y crisis ósea, 81.9% y 99% respectivamente) y la normalización de la hemoglobina (86.5%). La terapia de reemplazo enzimática con Imiglucerasa, a largo plazo en la población argentina demostró ser una herramienta eficaz para mejorar los parámetros clínicos y bioquímicos de la Enfermedad de Gaucher tipo1.Fil: Drelichman, G.. Gobierno de la Ciudad de Buenos Aires. Hospital General de Niños "Ricardo Gutiérrez"; ArgentinaFil: Fernández Escobar, Nicolás. Gobierno de la Ciudad de Buenos Aires. Hospital General de Niños "Ricardo Gutiérrez"; ArgentinaFil: Basack, Nora. Gobierno de la Ciudad de Buenos Aires. Hospital General de Niños "Ricardo Gutiérrez"; ArgentinaFil: Kohan, R.. Registro Argentino de Gaucher; ArgentinaFil: Watman, N.. Gobierno de la Ciudad de Buenos Aires. Hospital General de Agudos "Ramos Mejía"; ArgentinaFil: Bolesina, M.. Gobierno de la Ciudad de Buenos Aires. Hospital General de Agudos "Ramos Mejía"; ArgentinaFil: Elena, G.. Gobierno de la Ciudad de Buenos Aires. Hospital General de Niños Pedro Elizalde (ex Casa Cuna); ArgentinaFil: Veber, S. E.. Gobierno de la Ciudad de Buenos Aires. Hospital General de Niños Pedro Elizalde (ex Casa Cuna); ArgentinaFil: Dragosky, M.. Gobierno de la Ciudad de Buenos Aires. Hospital de Oncología Marie Curie; ArgentinaFil: Annetta, I.. Gobierno de la Ciudad de Buenos Aires. Hospital de Oncología Marie Curie; ArgentinaFil: Feliu, A.. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría "Juan P. Garrahan"; ArgentinaFil: Sciuccati, Gabriela. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría "Juan P. Garrahan"; ArgentinaFil: Cuello, María Fernanda. Provincia de Buenos Aires. Ministerio de Salud. Hospital de Niños "Sor María Ludovica" de la Plata; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Fynn, Alcira. Provincia de Buenos Aires. Ministerio de Salud. Hospital de Niños "Sor María Ludovica" de la Plata; ArgentinaFil: Dodelson de Kremer, Raquel. Provincia de Buenos Aires. Ministerio de Salud. Hospital de Niños "Sor María Ludovica" de la Plata; ArgentinaFil: Angaroni, Celia Juana. Provincia de Buenos Aires. Ministerio de Salud. Hospital de Niños "Sor María Ludovica" de la Plata; ArgentinaFil: Giner Ayala, Alicia. Provincia de Buenos Aires. Ministerio de Salud. Hospital de Niños "Sor María Ludovica" de la Plata; ArgentinaFil: Del Valle Oller, Ana María. Provincia de Buenos Aires. Ministerio de Salud. Hospital de Niños "Sor María Ludovica" de la Plata; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Guelbert, Norberto Bernardo. Provincia de Buenos Aires. Ministerio de Salud. Hospital de Niños "Sor María Ludovica" de la Plata; ArgentinaFil: Delgado, María Andrea. Provincia de Buenos Aires. Ministerio de Salud. Hospital de Niños "Sor María Ludovica" de la Plata; ArgentinaFil: Becerra, Adriana Berónica. Provincia de Buenos Aires. Ministerio de Salud. Hospital de Niños "Sor María Ludovica" de la Plata; ArgentinaFil: Oliveri, María Beatriz. Universidad de Buenos Aires. Facultad de Medicina. Hospital de Clínicas General San Martín; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Larroudé, M.. Centro Médico TIEMPO; ArgentinaFil: Masllorens, F.. Provincia de Buenos Aires. Ministerio de Salud. Hospital Nacional “Prof. Dr. A. Posadas"; ArgentinaFil: Szlago, M.. Fundación para el eEstudio de las Enfermedades Neurometabólicas; Argentina. Laboratorio de Neuroquímica “Dr. N. A. Chamoles”; ArgentinaFil: Schenone, A.. Laboratorio de Neuroquímica “Dr. N. A. Chamoles”; Argentina. Fundación para el eEstudio de las Enfermedades Neurometabólicas; Argentin

    Measurement of antiproton production from antihyperon decays in pHe collisions at √sNN=110GeV

    Get PDF
    The interpretation of cosmic antiproton flux measurements from space-borne experiments is currently limited by the knowledge of the antiproton production cross-section in collisions between primary cosmic rays and the interstellar medium. Using collisions of protons with an energy of 6.5 TeV incident on helium nuclei at rest in the proximity of the interaction region of the LHCb experiment, the ratio of antiprotons originating from antihyperon decays to prompt production is measured for antiproton momenta between 12 and 110GeV\!/c . The dominant antihyperon contribution, namely Λ¯ → p¯ π+ decays from promptly produced Λ¯ particles, is also exclusively measured. The results complement the measurement of prompt antiproton production obtained from the same data sample. At the energy scale of this measurement, the antihyperon contributions to antiproton production are observed to be significantly larger than predictions of commonly used hadronic production models

    Studies of η\eta and η\eta' production in pppp and ppPb collisions

    Full text link
    The production of η\eta and η\eta' mesons is studied in proton-proton and proton-lead collisions collected with the LHCb detector. Proton-proton collisions are studied at center-of-mass energies of 5.025.02 and 13 TeV13~{\rm TeV}, and proton-lead collisions are studied at a center-of-mass energy per nucleon of 8.16 TeV8.16~{\rm TeV}. The studies are performed in center-of-mass rapidity regions 2.5<yc.m.<3.52.5<y_{\rm c.m.}<3.5 (forward rapidity) and 4.0<yc.m.<3.0-4.0<y_{\rm c.m.}<-3.0 (backward rapidity) defined relative to the proton beam direction. The η\eta and η\eta' production cross sections are measured differentially as a function of transverse momentum for 1.5<pT<10 GeV1.5<p_{\rm T}<10~{\rm GeV} and 3<pT<10 GeV3<p_{\rm T}<10~{\rm GeV}, respectively. The differential cross sections are used to calculate nuclear modification factors. The nuclear modification factors for η\eta and η\eta' mesons agree at both forward and backward rapidity, showing no significant evidence of mass dependence. The differential cross sections of η\eta mesons are also used to calculate η/π0\eta/\pi^0 cross section ratios, which show evidence of a deviation from the world average. These studies offer new constraints on mass-dependent nuclear effects in heavy-ion collisions, as well as η\eta and η\eta' meson fragmentation.Comment: All figures and tables, along with machine-readable versions and any supplementary material and additional information, are available at https://lhcbproject.web.cern.ch/Publications/p/LHCb-PAPER-2023-030.html (LHCb public pages

    Observation of Cabibbo-suppressed two-body hadronic decays and precision mass measurement of the Ωc0\Omega_{c}^{0} baryon

    Full text link
    The first observation of the singly Cabibbo-suppressed Ωc0ΩK+\Omega_{c}^{0}\to\Omega^{-}K^{+} and Ωc0Ξπ+\Omega_{c}^{0}\to\Xi^{-}\pi^{+} decays is reported, using proton-proton collision data at a centre-of-mass energy of 13TeV13\,{\rm TeV}, corresponding to an integrated luminosity of 5.4fb15.4\,{\rm fb}^{-1}, collected with the LHCb detector between 2016 and 2018. The branching fraction ratios are measured to be B(Ωc0ΩK+)B(Ωc0Ωπ+)=0.0608±0.0051(stat)±0.0040(syst)\frac{\mathcal{B}(\Omega_{c}^{0}\to\Omega^{-}K^{+})}{\mathcal{B}(\Omega_{c}^{0}\to\Omega^{-}\pi^{+})}=0.0608\pm0.0051({\rm stat})\pm 0.0040({\rm syst}), B(Ωc0Ξπ+)B(Ωc0Ωπ+)=0.1581±0.0087(stat)±0.0043(syst)±0.0016(ext)\frac{\mathcal{B}(\Omega_{c}^{0}\to\Xi^{-}\pi^{+})}{\mathcal{B}(\Omega_{c}^{0}\to\Omega^{-}\pi^{+})}=0.1581\pm0.0087({\rm stat})\pm0.0043({\rm syst})\pm0.0016({\rm ext}). In addition, using the Ωc0Ωπ+\Omega_{c}^{0}\to\Omega^{-}\pi^{+} decay channel, the Ωc0\Omega_{c}^{0} baryon mass is measured to be M(Ωc0)=2695.28±0.07(stat)±0.27(syst)±0.30(ext)MeV/c2M(\Omega_{c}^{0})=2695.28\pm0.07({\rm stat})\pm0.27({\rm syst})\pm0.30({\rm ext})\,{\rm MeV}/c^{2}, improving the precision of the previous world average by a factor of four.Comment: All figures and tables, along with any supplementary material and additional information, are available at https://cern.ch/lhcbproject/Publications/p/LHCb-PAPER-2023-011.html (LHCb public pages

    Fraction of χc\chi_c decays in prompt J/ψJ/\psi production measured in pPb collisions at sNN=8.16\sqrt{s_{NN}}=8.16 TeV

    Full text link
    The fraction of χc1\chi_{c1} and χc2\chi_{c2} decays in the prompt J/ψJ/\psi yield, Fχc=σχcJ/ψ/σJ/ψF_{\chi c}=\sigma_{\chi_c \to J/\psi}/\sigma_{J/\psi}, is measured by the LHCb detector in pPb collisions at sNN=8.16\sqrt{s_{NN}}=8.16 TeV. The study covers the forward (1.5<y<4.01.5<y^*<4.0) and backward (5.0<y<2.5-5.0<y^*<-2.5) rapidity regions, where yy^* is the J/ψJ/\psi rapidity in the nucleon-nucleon center-of-mass system. Forward and backward rapidity samples correspond to integrated luminosities of 13.6 ±\pm 0.3 nb1^{-1} and 20.8 ±\pm 0.5 nb1^{-1}, respectively. The result is presented as a function of the J/ψJ/\psi transverse momentum pT,J/ψp_{T,J/\psi} in the range 1<pT,J/ψ<20<p_{T, J/\psi}<20 GeV/cc. The FχcF_{\chi c} fraction at forward rapidity is compatible with the LHCb measurement performed in pppp collisions at s=7\sqrt{s}=7 TeV, whereas the result at backward rapidity is 2.4 σ\sigma larger than in the forward region for 1<pT,J/ψ<31<p_{T, J/\psi}<3 GeV/cc. The increase of FχcF_{\chi c} at low pT,J/ψp_{T, J/\psi} at backward rapidity is compatible with the suppression of the ψ\psi(2S) contribution to the prompt J/ψJ/\psi yield. The lack of in-medium dissociation of χc\chi_c states observed in this study sets an upper limit of 180 MeV on the free energy available in these pPb collisions to dissociate or inhibit charmonium state formation.Comment: All figures and tables, along with machine-readable versions and any supplementary material and additional information, are available at https://cern.ch/lhcbproject/Publications/p/LHCb-PAPER-2023-028.html (LHCb public pages

    Measurement of ZZ boson production cross-section in pppp collisions at s=5.02\sqrt{s} = 5.02 TeV

    Full text link
    The first measurement of the ZZ boson production cross-section at centre-of-mass energy s=5.02\sqrt{s} = 5.02\,TeV in the forward region is reported, using pppp collision data collected by the LHCb experiment in year 2017, corresponding to an integrated luminosity of 100±2pb1100 \pm 2\,\rm{pb^{-1}}. The production cross-section is measured for final-state muons in the pseudorapidity range 2.020GeV/c2.0 20\,\rm{GeV/}\it{c}. The integrated cross-section is determined to be σZμ+μ=39.6±0.7(stat)±0.6(syst)±0.8(lumi) pb \sigma_{Z \rightarrow \mu^{+}\mu^{-}} = 39.6 \pm 0.7\,(\rm{stat}) \pm 0.6\,(\rm{syst}) \pm 0.8\,(\rm{lumi}) \ \rm{pb} for the di-muon invariant mass in the range 60<Mμμ<120GeV/c260<M_{\mu\mu}<120\,\rm{GeV/}\it{c^{2}}. This result and the differential cross-section results are in good agreement with theoretical predictions at next-to-next-to-leading order in the strong coupling. Based on a previous LHCb measurement of the ZZ boson production cross-section in ppPb collisions at sNN=5.02\sqrt{s_{NN}}=5.02 TeV, the nuclear modification factor RpPbR_{p\rm{Pb}} is measured for the first time at this energy. The measured values are 1.20.3+0.5(stat)±0.1(syst)1.2^{+0.5}_{-0.3}\,(\rm{stat}) \pm 0.1\,(\rm{syst}) in the forward region (1.53<yμ<4.031.53<y^*_{\mu}<4.03) and 3.60.9+1.6(stat)±0.2(syst)3.6^{+1.6}_{-0.9}\,(\rm{stat}) \pm 0.2\,(\rm{syst}) in the backward region (4.97<yμ<2.47-4.97<y^*_{\mu}<-2.47), where yμy^*_{\mu} represents the muon rapidity in the centre-of-mass frame.Comment: All figures and tables, along with any supplementary material and additional information, are available at https://cern.ch/lhcbproject/Publications/p/LHCb-PAPER-2023-010.html (LHCb public pages
    corecore