Generalized action invariants are identified for various models of drift wave turbulence in the presence of the mean shear flow. It is shown that the wave kinetic equation describing the interaction of the small scale turbulence and large scale shear flow can be naturally writen in terms of these invariants. Unlike the wave energy, which is conserved as a sum of small-and large-scale components...

OBJECTIVE Several hypotheses for the origin of the U wave in electrocardiograms have been proposed. We have set out to explore and test alternative modes for U-wave genesis via computer simulations. METHODS AND RESULTS A spatial model of a left ventricle has been constructed from 12 layers composed of cubic cells. Each cell is assigned its own time-dependent action potential with its own cont...

Magnetohydrodynamic (MHD) waves in the solar wind and magnetosphere are propagated in a medium whose velocity is comparable to or greater than the wave velocity and which varies in both space and time. In the approximation where the scales of the time and space variation are long compared with the period and wavelength, the ray-tracing equations can be generalized and then include an additional...

Microplastic (MP) debris is recognized to be one of the most serious threats marine environments. They are found in all seas and oceanic basins worldwide, even remote areas. This further proof that transport MPs very efficient. In present study, we focus our attention on MPs’ owing Stokes drift generated by sea waves. Recent studies have shown interaction between heavy particles leads unexpecte...

This paper presents an efficient numerical algorithm for the nonlinear wave-wave interactions that can be important in the evolution of coastal waves. Random sea waves of multiple frequencies always interact with each other and with the variable wind and pressure fields. As waves propagate and transform from deep to shallow water, it is generally difficult to determine the actual amount of nonl...