Reaction-diffusion equations are commonly used to model the growth and spreading of biological species. The classical diffusion term implies a Gaussian dispersal kernel in the corresponding integro-difference equation, which is often unrealistic in practice. In this paper, we propose a fractional reaction-diffusion equation where the classical second derivative diffusion term is replaced by a f...

A family of one–dimensional multi–species reaction–diffusion processes on a lattice is introduced. It is shown that these processes are exactly solvable, provided a nonspectral matrix equation is satisfied. Some general remarks on the solutions to this equation, and some special solutions are given. The large–time behavior of the conditional probabilities of such systems are also investigated. ...

Alleviated melanin formation in the skin through inhibition of tyrosine-tyrosinase reaction is one of the major targets of cosmetics for whitening ability. Since melanin has a pivotal role for photoprotection, there are pros and cons of inhibition of melanin formation. This study applying electron spin resonance (ESR)-spin trapping method revealed that (•)H and (•)OH are generated through tyros...

We present an approach to the determination of causal connectivities and part of the kinetics of complex reaction systems. Our approach is based on analytical and computational methods for studying the effects of a pulse change of concentration of a chemical species in a reaction network, either at equilibrium or in a nonequilibrium stationary state. Such disturbances generally propagate throug...

When mice infected with the parasites of caderas, dourine, nagana, surra of India, or surra of Mauritius are properly treated with various therapeutic agents, a temporary immunity is produced. As the immunity is specific (I), the hope was at one time entertained that the reaction might be of service in differentiating trypanosome species. This expectation, however, almost vanished when the deli...

A method for classifying n-species reaction-diffusion models, admitting shock solutions is presented. The most general one-dimensional twospecies reaction-diffusion model with nearest neighbor interactions admitting uniform product measures as the stationary states is studied. Satisfying more constraints, these models may experience single-shock solutions. These models are generalized to multi-...

A generalization of reaction-diffusion models to multigeneration biological species is presented. It is based on more complex random walks than those in previous approaches. The new model is developed analytically up to infinite order. Our predictions for the speed agree to experimental data for several butterfly species better than existing models. The predicted dependence for the speed on the...

reactive oxygen species (ros)plays an important role in sperm motility. the physiological generation at low concentration induces beneficial effects on sperm functions and plays a significant role in sperm metabolism. meanwhile, the excessive generation of reactive oxygen species can overwhelm protective mechanism and triggers changes in lipid and protein layers of sperm plasma membrane, which ...

For three typical sets of small reaction networks (networks with two reactions, one irreversible and reversible reaction, or reversible-reaction pairs), we completely answer the challenging question “What is smallest subset all multistable such that any network outside contains either more species reactants than in this subset?"

Aspergillus species have recently caused increasing numbers of life-threatening acute invasive infections in immunocompromised patients (Kontoyiannis et al., 2002). The steadily increasing incidence of invasive aspergillosis over the last few decades is ascribable to the increasing number of patients undergoing chemotherapy, bone marrow or solid organ transplantation and intensive corticosteroi...