After a discrete two-species predator-prey system with ratio-dependent functional response is topologically and equivalently reduced, some new dynamical properties for the are formulated. The one existence local stability all equilibria of this system. Although corresponding results equilibrium $$E_3$$ have been presented in known literature, our more complete. other is, what’s important diffic...

We derive an expression for resonance energy transfer between a pair of chromophores embedded in a condensed medium by considering the energy splitting of the chromophores from their resonant excited states. We employ time-dependent density functional response theory in our derivation. The linear response theory treatment is rigorous within the framework of time-dependent density functional the...

Abstract. In this paper, a predator-prey system with Holling type II functional response and stage structure is investigated. By analyzing the corresponding characteristic equations, the local stability of each of feasible equilibria of the system is studied. The existence of the orbitally asymptotically stable periodic solution is established. By using suitable Lyapunov functions and the LaSal...

In this paper, we present two iterative algorithms for approximating the absorption spectrum of molecules within the linear response of time-dependent density functional theory (TDDFT) framework. These methods do not attempt to compute eigenvalues or eigenvectors of the linear response matrix. They are designed to approximate the absorption spectrum as a function directly. They take advantage o...

Within the adiabatic approximation, time-dependent density functional theory yields only single excitations. Near states of double excitation character, the exact exchange-correlation kernel has a strong dependence on frequency. We derive the exact frequency-dependent kernel when a double excitation mixes with a single excitation, well separated from the other excitations, in the limit that the...

Background: Stimulants addition and abuse can cause some functional and morphological changes in the normal function of glands and hormones. Methamphetamine as an addictive stimulant drug affects the Hypothalamic-pituitary-adrenal (HPA) axis and consequently makes some changes in the psychological state of the drug users. The present study aims to examine the relationship between plasma levels ...

background: central obesity and hyperinsulinaemia of polycystic ovary syndrome (pcos) are associated with chronic sympathetic over activity. objective: to evaluate the autonomic functions and to indicate the superiority, if any, for those functions in the diagnosis of sympathetic over activity in pcos women. materials and methods: sixty-four pcos patients and 40 women served as the control grou...

We present a linear-response approach for time-dependent density-functional theories using time-adiabatic functionals. The resulting theory can be performed both in the time and in the frequency domain. The derivation considers an impulsive perturbation after which the Kohn-Sham orbitals develop in time autonomously. The equation describing the evolution is not strictly linear in the wave funct...