Recent experiments have measured collisional frequency shifts in polarized fermionic alkaline-earth atoms using 1S0-3P0 Rabi spectroscopy. Here, we provide a first-principles nonequilibrium theoretical description of the interaction frequency shifts starting from the microscopic many-body Hamiltonian. Our formalism describes the dependence of the frequency shift on excitation inhomogeneity, int...

A saturating hamiltonian is presented in a relativisti-cally covariant formalism. The interaction is described by scalar and vector mesons, with coupling strengths adjusted to the nuclear matter. No explicit density dependence is assumed. The hamilto-nian is applied in a QMD calculation to determine the fragment distribution in O + Br collision at different energies (50 – 200 MeV/u) to test the...

Negative density dependence may cause reduced clustering among individuals of the same species, and evidence is accumulating that conspecific density-dependent self-thinning is an important mechanism regulating the spatial structure of plant populations. This study evaluates that specific density dependence in three very large observational studies representing three successional stages in a te...

Density dependence is the major process keeping the sizes of natural populations within bounds. In organisms with complex life cycles, the stage at which density dependence occurs and whether it occurs in one or several life stages have important consequences for the dynamics of their populations. I manipulated density of pool frogs (Rana lessonae) during the aquatic larval and the terrestrial ...

stability of the π-π stacking interactions in the ben||n-substituted-coronene complexes was studied using the computational quantum chemistry methods (where ben is benzene and || denotes π-π stacking interaction, and n-substituted-coronene is coronene molecule which substituted with different number of n atoms). the results reveal simultaneous effects of structure and number of heteroatom on th...

where kD=1.602 10 Gy⋅g/MeV — energy conversion factor from MeV to Gy×g, (obtained from the known ratio: 1 MeV=1.602 10 J); Е – neutron energy, MeV; Ф(r,Е) dE – neutron flux in the point r on the energy interval dE, neutron/cm/s: ni – atomic density of the i-th nuclide of the medium, atom/cm; σij(E) –microscopic cross-section of reaction j at interaction of a neutron with energy Е on the i-th nu...

In this study interaction of phenothiazine sulfur dye with (5, 5) armchair open-end boron nitride nanotubes (BNNTs) in interaction (with a length of 7 Å) was investigated. The impacts of the estereoelectronic effect associated with donor-acceptor electron delocalizations, dipole-dipole interactions and total steric exchange energies on the structural and electronic properties and reactivity of ...

There is increasing interest in the role played by density-dependent mortality from natural enemies, particularly plant pathogens, in promoting the coexistence and diversity of tropical trees. Here, we review four issues in the analysis of pathogen-induced density dependence that have been overlooked or inadequately addressed. First, the methodology for detecting density dependence must be robu...