4,961 research outputs found

    Moyal star product approach to the Bohr-Sommerfeld approximation

    Full text link
    The Bohr-Sommerfeld approximation to the eigenvalues of a one-dimensional quantum Hamiltonian is derived through order ℏ2\hbar^2 (i.e., including the first correction term beyond the usual result) by means of the Moyal star product. The Hamiltonian need only have a Weyl transform (or symbol) that is a power series in ℏ\hbar, starting with ℏ0\hbar^0, with a generic fixed point in phase space. The Hamiltonian is not restricted to the kinetic-plus-potential form. The method involves transforming the Hamiltonian to a normal form, in which it becomes a function of the harmonic oscillator Hamiltonian. Diagrammatic and other techniques with potential applications to other normal form problems are presented for manipulating higher order terms in the Moyal series.Comment: 27 pages, no figure

    Integrated control of Fascioliasis in Latin America: Results of an International Atomic Energy Agency Project

    Get PDF
    Even though Fascioliasis has been known for centuries, it is now emerging in many parts of the world . Human cases are rising, two decades ago the estimates were of a few thousand , current estimates reach many millions. The human endemic areas are highest in Latin American countries and animal fascioliasis greatly affects livestock all through the region, often of poor subsistence farmers, thus decreasing even more their meager earnings and contributing to the cycle of disease and poverty . The enourmous geographical diversity of the regions affected by fascioliasis in Latin America ranges from the cold, snowcovered Patagonia to the simmering tropics of Central America

    EFECTO DEL ÁCIDO CÍTRICO COMO PRETRATAMIENTO SOBRE LA ACTIVIDAD DE AGUA Y COMPORTAMIENTO DE SORCIÓN EN CALLO DE ALMEJA SECO (Nodipecten subnodosus)

    Get PDF
    En presente estudio se aplicó un tratamiento de inmersión en åcido cítrico a callo de almeja, con el objetivo de reducir el tiempo de secado de la almeja mano de león. Las muestras se sometieron a inmersión en åcido cítrico 0.1 M, durante cero (control), una y tres h. Se evaluó el efecto del pre-tratamiento de inmersión en solución åcida y la temperatura de secado (50, 60 y 70 °C), sobre la aw y el fenómeno de sorción en el callo seco. Ambas variables mostraron un efecto significativo (

    Impacto de la tĂ©cnica quirĂșrgica en patient blood management

    Get PDF
    PO-067 IntroducciĂłn: La autotransfusiĂłn es un mĂ©todo de ahorro de sangre frecuentemente utilizado en procedimientos quirĂșrgicos con elevado riesgo hemorrĂĄgico. La cistectomĂ­a radical por neoplasia de vejiga es una intervenciĂłn quirĂșrgica agresiva, con gran morbimortalidad y altos requerimientos transfusionales. Por este motivo, la autodonaciĂłn de sangre previa a cirugĂ­a se sigue utilizando en estos pacientes. Sin embargo, el abordaje laparoscĂłpico parece disminuir la necesidad de transfusiĂłn y podrĂ­a suponer en sĂ­ misma una herramienta de ahorro de hemoderivados. El objetivo de este estudio es valorar la repercusiĂłn de esta novedad tĂ©cnica en la tasa de sangrados y requerimientos transfusionales en estos pacientes. Material y mĂ©todos: Estudio observacional descriptivo y retrospectivo, realizado en el Hospital ClĂ­nico Lozano Blesa de Zaragoza, desde enero de 2012 a junio de 2017. Se incluyeron pacientes intervenidos de cistectomĂ­a radical, clasificados segĂșn en abordaje quirĂșrgico utilizado en cirugĂ­a abierta o laparoscĂłpica, y se compararon los dos grupos en tĂ©rminos de sangrado y requerimientos transfusionales durante la cirugĂ­a y tras la misma. Resultados: Se registraron un total de 164 pacientes, 89, 6% varones y 10, 4% mujeres, con una mediana de edad de 67, 1±9, 1 años. El 35, 4% de las intervenciones quirĂșrgicas fueron realizadas por vĂ­a laparoscĂłpica. A pesar de que este abordaje supuso un mayor tiempo de cirugĂ­a, de forma estadĂ­sticamente significativa (p<0, 003), las tasas de sangrado durante y tras la intervenciĂłn, asĂ­ como el consumo de hemoderivados fueron significativamente menores (p<0, 001). ..

    Sonidegib as a Locally Advanced Basal Cell Carcinoma Therapy in Real-life Clinical Setting: A National Multicentre Study

    Full text link
    Background: Basal cell carcinoma (BCC) is the most prevalent cancer. A minority of BCCs have an aggressive behaviour (laBCC) and may require hedgehog pathway inhibitors such as sonidegib as its treatment. Objective: To describe the use of sonidegib in a large number of patients and provide more data on its real-life efficacy and safety profile.Methods: We conducted a retrospective and multicentric study that included patients treated with sonidegib. Epidemiological, effectiveness and safety data were collected.Results: A total of 82 patients with a mean age of 73.9 years were included. Ten patients had Gorlin syndrome. Median treatment duration was 6 months. Median follow-up duration was 34.2 months. Globally, 81.7% of the patients showed clinical improvement (52.4% partial response and 29.3% complete response), 12.2% clinical stability and 6.1% disease progression. There was no statistically significant difference in clinical improvement between the 24 h and 48 h sonidegib posology. After 6 months of treatment, 48.8% of the patients discontinued sonidegib. Prior vismodegib treatment and recurrent primary BCC were associated with a poorer response to sonidegib. At 6 months of treatment, 68.3% of the patients experienced at least one adverse effect. Conclusion: Sonidegib shows good effectiveness and acceptable safety profile in usual clinical practice.& COPY; 2023 AEDV. Published by Elsevier Espan & SIM;a, S.L.U.This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/)

    Observation of an Excited Bc+ State

    Get PDF
    Using pp collision data corresponding to an integrated luminosity of 8.5 fb-1 recorded by the LHCb experiment at center-of-mass energies of s=7, 8, and 13 TeV, the observation of an excited Bc+ state in the Bc+π+π- invariant-mass spectrum is reported. The observed peak has a mass of 6841.2±0.6(stat)±0.1(syst)±0.8(Bc+) MeV/c2, where the last uncertainty is due to the limited knowledge of the Bc+ mass. It is consistent with expectations of the Bc∗(2S31)+ state reconstructed without the low-energy photon from the Bc∗(1S31)+→Bc+Îł decay following Bc∗(2S31)+→Bc∗(1S31)+π+π-. A second state is seen with a global (local) statistical significance of 2.2σ (3.2σ) and a mass of 6872.1±1.3(stat)±0.1(syst)±0.8(Bc+) MeV/c2, and is consistent with the Bc(2S10)+ state. These mass measurements are the most precise to date

    Differential branching fraction and angular analysis of the decay B0→K∗0ÎŒ+Ό−

    Get PDF
    The angular distribution and differential branching fraction of the decay B 0→ K ∗0 ÎŒ + ÎŒ − are studied using a data sample, collected by the LHCb experiment in pp collisions at s√=7 TeV, corresponding to an integrated luminosity of 1.0 fb−1. Several angular observables are measured in bins of the dimuon invariant mass squared, q 2. A first measurement of the zero-crossing point of the forward-backward asymmetry of the dimuon system is also presented. The zero-crossing point is measured to be q20=4.9±0.9GeV2/c4 , where the uncertainty is the sum of statistical and systematic uncertainties. The results are consistent with the Standard Model predictions

    Measurement of the mass and lifetime of the Ωb−\Omega_b^- baryon

    Get PDF
    A proton-proton collision data sample, corresponding to an integrated luminosity of 3 fb−1^{-1} collected by LHCb at s=7\sqrt{s}=7 and 8 TeV, is used to reconstruct 63±963\pm9 Ωb−→Ωc0π−\Omega_b^-\to\Omega_c^0\pi^-, Ωc0→pK−K−π+\Omega_c^0\to pK^-K^-\pi^+ decays. Using the Ξb−→Ξc0π−\Xi_b^-\to\Xi_c^0\pi^-, Ξc0→pK−K−π+\Xi_c^0\to pK^-K^-\pi^+ decay mode for calibration, the lifetime ratio and absolute lifetime of the Ωb−\Omega_b^- baryon are measured to be \begin{align*} \frac{\tau_{\Omega_b^-}}{\tau_{\Xi_b^-}} &= 1.11\pm0.16\pm0.03, \\ \tau_{\Omega_b^-} &= 1.78\pm0.26\pm0.05\pm0.06~{\rm ps}, \end{align*} where the uncertainties are statistical, systematic and from the calibration mode (for τΩb−\tau_{\Omega_b^-} only). A measurement is also made of the mass difference, mΩb−−mΞb−m_{\Omega_b^-}-m_{\Xi_b^-}, and the corresponding Ωb−\Omega_b^- mass, which yields \begin{align*} m_{\Omega_b^-}-m_{\Xi_b^-} &= 247.4\pm3.2\pm0.5~{\rm MeV}/c^2, \\ m_{\Omega_b^-} &= 6045.1\pm3.2\pm 0.5\pm0.6~{\rm MeV}/c^2. \end{align*} These results are consistent with previous measurements.Comment: 11 pages, 5 figures, All figures and tables, along with any supplementary material and additional information, are available at https://lhcbproject.web.cern.ch/lhcbproject/Publications/LHCbProjectPublic/LHCb-PAPER-2016-008.htm

    Measurement of the Bs0→J/ψηB_{s}^{0} \rightarrow J/\psi \eta lifetime

    Get PDF
    Using a data set corresponding to an integrated luminosity of 3fb−13 fb^{-1}, collected by the LHCb experiment in pppp collisions at centre-of-mass energies of 7 and 8 TeV, the effective lifetime in the Bs0→J/ψηB^0_s \rightarrow J/\psi \eta decay mode, τeff\tau_{\textrm{eff}}, is measured to be τeff=1.479±0.034 (stat)±0.011 (syst)\tau_{\textrm{eff}} = 1.479 \pm 0.034~\textrm{(stat)} \pm 0.011 ~\textrm{(syst)} ps. Assuming CPCP conservation, τeff\tau_{\textrm{eff}} corresponds to the lifetime of the light Bs0B_s^0 mass eigenstate. This is the first measurement of the effective lifetime in this decay mode.Comment: All figures and tables, along with any supplementary material and additional information, are available at https://lhcbproject.web.cern.ch/lhcbproject/Publications/LHCbProjectPublic/LHCb-PAPER-2016-017.htm

    Bose-Einstein correlations of same-sign charged pions in the forward region in pp collisions at √s=7 TeV

    Get PDF
    Bose-Einstein correlations of same-sign charged pions, produced in protonproton collisions at a 7 TeV centre-of-mass energy, are studied using a data sample collected by the LHCb experiment. The signature for Bose-Einstein correlations is observed in the form of an enhancement of pairs of like-sign charged pions with small four-momentum difference squared. The charged-particle multiplicity dependence of the Bose-Einstein correlation parameters describing the correlation strength and the size of the emitting source is investigated, determining both the correlation radius and the chaoticity parameter. The measured correlation radius is found to increase as a function of increasing charged-particle multiplicity, while the chaoticity parameter is seen to decreas
    • 

    corecore