– We report on susceptibility, magnetization, 23 Na NMR, and specific heat data of the spin-chain material NaCu2O2 in the paramagnetic and ordered phases. Below 13 K, where a sharp field-dependent specific heat peak appears, the NMR lineshape points to an incommensurate static modulation of the local magnetic field consistent with a spiral state of the Cu… (More)
In frames of a rather conventional quantum-chemical approach, which combines the crystal field and the ligand field models we have addressed different charge transfer (CT) states and O2p − M n3d CT transitions in M nO 9− 6 octahedra. The many-electron dipole transition matrix elements were calculated using the Racah algebra for the cubic point group. Simple… (More)
The singlet-triplet magnetism and induced spin fluctuations in the high-T c copper oxides.
The Kramers-Klein equation is a special Fokker-Planck equation describing the brownian motion in a potential. This equation is used in different areas of biology, chemistry and physics. In this paper we present the comparison between numerical and analytical solutions in case of a linear force and usage of multi-core CPU and GPU for solving Kramers-Klein… (More)
An integrative model of the calcium dynamics in cardiac pacemaker cells is developed taking into account a synergetic effect of the interaction between an outer membrane oscillator and an intracellular calcium oscillator ("membrane and Ca(2+)-clock"). The main feature of the model is a description of the stochastic dynamics of Ca2+ release units within the… (More)
I. Intracellular calcium (Ca 2+) dynamics is the basis of cardiac cell functioning, being the pivot of both of the electroomechanical coupling in cardiomyy ocytes and the cardiac rhythm formation in sinoatrial node cells (SANCs). Cardiac cell contractions are activated by an increase in the intracellular concentration of Ca 2+ , most of which is… (More)
The article illustrates the method of mathematical modelling in physiology as a unique tool to study physiological processes. A number of demonstrated examples appear as a result of long-term experience in mathematical modelling of electrical and mechanical phenomena in the heart muscle. These examples are presented here to show that the modelling provides… (More)