Relativistic description of second-order correction to nuclear magnetic moments with point-coupling residual interaction

Using the single particle states and the residual interaction derived from the relativistic point-coupling model with the PC-F1 parameter set,the second-order core polarization corrections to nuclear magnetic moments of LS closed shell nuclei ±1 nucleon with A = 15,17,39 and 41 are studied and compared with previous non-relativistic results.It is found that the second-order corrections are significant.With these corrections,the isovector magnetic moments of the concerned nuclei are well reproduced,especially those for A = 17 and A = 41.

Binding Energy, Root Mean Square Radius and Magnetic Dipole Moment of the Triton Nucleus

The basis functions of the translation invariant shell model are used to construct the ground state nuclear wave functions of 3H. The used residual two-body interactions consist of central, tensor, spin orbit and quadratic spin orbit terms with Gaussian radial dependence. The parameters of these interactions are so chosen in such a way that they represent the long-range attraction and the short-range repulsion of the nucleon-nucleon interactions. These parameters are so chosen to reproduce good agreement between the calculated values of the binding energy, the root mean-square radius, the D-state probability, the magnetic dipole moment and the electric quadrupole moment of the deuteron nucleus. The variation method is then used to calculate the binding energy of triton by varying the oscillator parameter which exists in the nuclear wave function. The obtained nuclear wave functions are then used to calculate the root mean-square radius and the magnetic dipole moment of the triton.

Approaching nuclei through multiple perspectives and diverse models： Patterns, symmetries, interactions

Nuclei are complex objects yet display remarkable simplicities and regular patterns. The study of these and their origins has long been one of the twin pillars of nuclear structure research. We will discuss the behavior of atomic nuclei from this point of view. A key element will be the advantages of looking at the same data from different perspectives and of inter-relating these perspectives.

Mapping allosteric pathway in NIa-Pro using computational approach

Background:Computer simulation studies complement in vitro experiments and provide avenue to understand allosteric regulation in the absence of other molecular viewing techniques.Molecular dynamics captures internal motion within the protein and enables tracing the communication path between a catalytic site and a distal allosteric site.In this article,we have identified the communication pathway between the viral protein genome linked(VPg)binding region and catalytic active site in nuclear inclusion protein-a protease(NIa-Pro).Methods:Molecular dynamics followed by in silico analyses have been used to map the allosteric pathway.Results:This study delineates the residue interaction network involved in allosteric regulation of NIa-Pro activity by VPg.Simulation studies indicate that point mutations in the VPg interaction interface of NIa-Pro lead to disruption in these networks and change the orientation of catalytic residues.His142Ala and His167Ala mutations do not show a substantial change in the overall protease structure,but rather in the residue interaction network and catalytic site geometry.Conclusion:Our mutagenic study delineates the allosteric pathway and facilitates the understanding of the modulation of NIa-Pro activity on a molecular level in the absence of the structure of its complex with the known regulator VPg.Additionally,our in silico analysis explains the molecular concepts and highlights the dynamics behind the previously reported wet lab study findings.

Nuclear structure around ^(80)Zr

Recent years have witnessed intense activity concerning the study of nuclei with equal numbers of neutrons and protons （N = Z）. Exotic properties have been exhibited in the N = Z nuclei, especially in those with atomic masses around 80. In the present paper, the projected shell model（PSM）together with a relativistic Hartree-Bogoliubov （RHB） theory is used to study the nuclear structure near the N = Z line in the mass A ≈ 80 region. For three Zr isotopes 80,82,84Zr, the projected potential energy surfaces and ground state bands are calculated. It is shown that shape coexistence occurs in all of these nuclei. Moreover, we find that the residual neutron-proton interaction strongly affects the ground state band of 80Zr; however, it slightly modifies those of 82Zr and 84Zr.