Reaction dynamics of exotic and stable weakly-bound nuclei using a four-body continuum-discretized coupled-channels formalism

Reactions induced by four weakly-bound nuclei on a lead target, at energies around the Coulomb barrier, are described using the same four-body continuum-discretized coupled-channels formalism. The nuclei considered are the halo nuclei 11Li and 6He, the stable nucleus 9Be and the proton-rich nucleus 10C. The differences and similarities on the reaction dynamics are addressed.

Critical nucleus of Greek-key-like core of α-synuclein protofibril and its disruption by dopamine and norepinephrine

Protofibrillar trimer is the critical nucleus for the αS fibril formation, and the tetramer is the minimal stable nucleus. The interactions of DA/NE with αS trimer/tetramer disrupt the backbone H-bonds and destabilize the αS protofibrils.

Swi5–Sfr1 stimulates Rad51 recombinase filament assembly by modulating Rad51 dissociation

Eukaryotic Rad51 protein is essential for homologous-recombination repair of DNA double-strand breaks. Rad51 recombinases first assemble onto single-stranded DNA to form a nucleoprotein filament, required for function in homology pairing and strand exchange. This filament assembly is the first regulation step in homologous recombination. Rad51 nucleation is kinetically slow, and several accessory factors have been identified to regulate this step. Swi5–Sfr1 (S5S1) stimulates Rad51-mediated homologous recombination by stabilizing Rad51 nucleoprotein filaments, but the mechanism of stabilization is unclear. We used single-molecule tethered particle motion experiments to show that mouse S5S1 (mS5S1) efficiently stimulates mouse RAD51 (mRAD51) nucleus formation and inhibits mRAD51 dissociation from filaments. We also used single-molecule fluorescence resonance energy transfer experiments to show that mS5S1 promotes stable nucleus formation by specifically preventing mRAD51 dissociation. This leads to a reduction of nucleation size from three mRAD51 to two mRAD51 molecules in the presence of mS5S1. Compared with mRAD51, fission yeast Rad51 (SpRad51) exhibits fast nucleation but quickly dissociates from the filament. SpS5S1 specifically reduces SpRad51 disassembly to maintain a stable filament. These results clearly demonstrate the conserved function of S5S1 by primarily stabilizing Rad51 on DNA, allowing both the formation of the stable nucleus and the maintenance of filament length.

Skyrme-Extended-Thomas-Fermi Approach Method In Investigation of Nuclear Ground State Properties of 208Pb

In this research, it is performed the nuclear ground state properties investigation of 208Pb by using the SETF method with SLy4 set parameters. The energy optimization calculation is performed using SETFA code. The SETFA results are in good agreement with the related experiment results, and also with the results of the HFBRAD and HFODD- HFBTHO codes. It is can be indicated that Skyrme-Extended-Thomas-Fermi method can be used to explain the nuclear ground state properties, especially even-stable nucleus.