447 research outputs found

    Relativistic Energy Density Functional Description of Shape Transition in Superheavy Nuclei

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    Relativistic energy density functionals (REDF) provide a complete and accurate, global description of nuclear structure phenomena. A modern semi-empirical functional, adjusted to the nuclear matter equation of state and to empirical masses of deformed nuclei, is applied to studies of shapes of superheavy nuclei. The theoretical framework is tested in a comparison of calculated masses, quadrupole deformations, and potential energy barriers to available data on actinide isotopes. Self-consistent mean-field calculations predict a variety of spherical, axial and triaxial shapes of long-lived superheavy nuclei, and their alpha-decay energies and half-lives are compared to data. A microscopic, REDF-based, quadrupole collective Hamiltonian model is used to study the effect of explicit treatment of collective correlations in the calculation of Q{\alpha} values and half-lives.Comment: 23 pages, 10 figure

    Relativistic mean field study of the properties of Z=117 nucleus and the decay chains of 293,294^{293,294}117 isotopes

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    We have calculated the binding energy, root-mean-square radius and quadrupole deformation parameter for the recently synthesized superheavy element Z=117, using the axially deformed relativistic mean field (RMF) model. The calculation is extended to various isotopes of Z=117 element, strarting from A=286 till A=310. We predict almost spherical structures in the ground state for almost all the isotopes. A shape transition appears at about A=292 from prolate to a oblate shape structures of Z=117 nucleus in our mean field approach. The most stable isotope (largest binding energy per nucleon) is found to be the 288^{288}117 nucleus. Also, the Q-value of α\alpha-decay QαQ_\alpha and the half-lives TαT_{\alpha} are calculated for the α\alpha-decay chains of 293^{293}117 and 294^{294}117, supporting the magic numbers at N=172 and/ or 184.Comment: 6 Pages and 8 Figure

    Echocardiographic evaluation of right ventricular systolic function: The traditional and innovative approach

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    Estimation of right ventricular (RV) performance still remains technically challenging due to its anatomical and functional distinctiveness. The current guidelines for the echocardiographic quantification of RV function recommend using multiple indices to describe the RV in a thorough and comprehensive manner, such as RV index of myocardial performance, tricuspid annular plane systolic excursion, fractional area change, Doppler tissue imaging-derived tricuspid lateral annular systolic velocity (S’-wave), three-dimensional RV ejection fraction (3D RVEF), RV longitudinal strain (RVLS)/strain rate by speckle- tracking echocardiography (STE). Among these, the last one mentioned here is an innovative and a particularly promising tool that yields more precise information about complex regional and global RV mechanics. STE was initially designed to evaluate left ventricular function, but recently it has been introduced to assess RV performance, which is difficult due to its unique structure and physiology. Many studies have shown that both free wall and 6-segment RVLS present a stronger correlation with the RVEF assessed by cardiac magnetic resonance than conventional parameters and seem to be more sensitive in detecting myocardial dysfunction at an earlier, subclinical stage

    Alpha decay chains study for the recently observed superheavy element Z=117 within the Isospin Cluster Model

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    The recently observed α\alpha-decay chains 293294117^{293-294}117 were produced by the fusion reactions with target 249Bk^{249}Bk and projectile 48Ca^{48}Ca at Dubna in Russia. The reported cross-sections for the mentioned reaction are σ=0.5(+1.1,0.4)\sigma=0.5(+1.1,-0.4)pb and σ\sigma=1.3(+1.5,-0.6)pbpb at E=35MeVE^{*}=35MeV and E=39MeVE^{*}=39MeV, respectively. The Q-values of α\alpha-decay and the half-lives Log10T1/2αLog_{10}T^{\alpha}_{1/2}(s) are calculated for the α\alpha-decay chains of 293294117^{293-294}117 nuclei, within the framework of Isospin Cluster Model (ICM). In the ICM model the proximity energy is improved by using the isospin dependent radius of parent, daughter and alpha particle. The binding energy B(Ai,Zi)B(A_{i}, Z_{i}) (i=1,2) of any nucleus of mass number A and atomic number Z was obtained from a phenomenological and more genaralized BW formula given by \cite{samanta02}. The calculated results in ICM are compared with the experimental results and other theoretical Macro-Microscopic(M-M), RMF(with NL3 and SFU Gold forces parameter) model calculations. The estimated values of α\alpha-decay half-lives are in good agreement with the recent data. The ICM calculation is in favor of the persence of magic number at N=172

    Sprawozdanie z kursu "Endoskopia Operacyjna w Ginekologii"

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    Sprawozdanie z 9 Kongresu Europejskiego Towarzystwa Endoskopii Ginekologicznej (ESGE)

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