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Comment: Proceedings of the 12th Conference on Problems in Theoretical Nuclear Physics, to appear in Journal of Physics, Conference Series
Comment: Revtex4, 19 pages, 8 eps figures, to be published in Phys. Rev. C
A full implementation of the Boltzmann-Langevin equation for fermionic systems is introduced in a transport model for dissipative collisions among heavy nuclei. Fluctuations are injected in phase space and not, like in more conventional approaches, as a projection on suitable subspaces. The advantage of this model is to be specifically adapted to describe processes characterised by instabilities, like the formation of fragments from a hot nuclear system, and by dissipation, like the transparency in nucleus-nucleus collisions.
Comment: 18 RevTex4 pages, 6 eps figures
Recently, the INDRA collaboration has investigated links between entrance channel, collective expansion and fragmentation features, in the context of heavy ion collisions at Fermi energies . To go further in this direction, a full comparison between transport theory results (the Stochastic-Mean-Field (SMF) approach is employed) and multifragmentation data [3] will be discussed. In a first part, the question of centrality selection is addressed. Starting from simulation events in the range of impact parameter 0-4 fm, we apply the same dynamical selection as that used experimentally to sort out the so-called "Quasi-Fusion" sources. To probe the link between the fragmentation regime and the system collective expansion, we analyse reactions in the beam-energy range between 25 and 50 MeV/A. Then we extract, looking at the evolution of the s...
Natural killer (NK) cells are innate lymphocytes that play important roles in the defense against microbial pathogens through secretion of IFN-γ and recognition and lysis of virally or bacterially infected host cells. A recently identified population of NK-like cells that shares characteristics of both NK cells and lymphoid tissue inducer (LTi) cells promotes innate immune responses in epithelial tissue through the secretion of IL-22. In contrast to classical NK cells, NK-like cells are localized preferentially at mucosal sites, such as the intestinal mucosa. In this review, we consider the function of NK and NK-like cells in anti-microbial defense as well as the maintenance of tissue integrity in the mucosal epithelium of the intestine, lung, and female reproductive tract. Current experimental evidence supports an important protective...
We investigate the occurrence of bifurcations in the dynamical trajectories depicting nuclear collisions at Fermi energies. The quantitative description of the reaction dynamics is obtained within a novel one-body transport approach, based on the solution of the Boltzmann-Langevin equation in three dimensions, with a broad applicability for dissipative fermionic dynamics. Dilute systems formed in central collisions are shown to fluctuate between two energetically favourable mechanisms: reverting to a compact shape or rather disintegrating into several fragments. The latter result can be connected to the recent observation of bimodal distributions for quantities characterising fragmentation processes.
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