Saccharomyces cerevisiae (baker’s yeast) can exhibit sustained oscillations during the operation in a continuous bioreactor that adversely affects its stability and productivity. Because of heterogeneous nature of cell populations, the cell population balance equation (PBE) can be used to capture the dynamic behavior of such cultures. In this work, an unstructured-segregated model is used f...

Population dynamics are often subject to random independent changes in the environment. For the two strategy stochastic replicator dynamic, we assume that stochastic changes in the environment replace the payoffs and variance. This is modeled by a continuous time Markov chain in a finite atom space. We establish conditions for this dynamic to have an analogous characterization of the long-run b...

In [19], Sighesada, Kawasaki and Teramoto presented a system of partial differential equations for modeling spatial segregation of interacting species. Apart from competitive Lotka-Volterra (reaction) and population pressure (cross-diffusion) terms, a convective term modeling the populations atraction to more favorable environmental regions is included. In this article, we introduce a modificat...

A transposable element can be defined as a DNA sequence capable of moving to new sites in the genome. Such DNA sequences have been described in a wide range of organisms. The evolutionary processes affecting transposable elements can thus be divided into two categories: changes in sequence and changes in genomic location. As with other types of evolutionary change, the nature of the evolutionar...

Bond Fukui functions and matrices are introduced for ab initio levels of theory using a Mulliken atoms in molecules model. It is shown how these indices may be obtained from first-order density matrix derivatives without need for going to second-order density matrices as in a previous work. The importance of taking into account the nonorthogonality of the basis in ab initio calculations is show...

Abstract. The global existence of a non-negative weak solution to a multi-dimensional parabolic strongly coupled model for two competing species is proved. The main feature of the model is that the diffusion matrix is non-symmetric and generally not positive definite and that the non-diagonal matrix elements (the cross-diffusion terms) are allowed to be “large”. The ideas of the existence proof...

[3] David F. Anderson, An efficient finite difference method for parameter sensitivities of continuous time markov chains, Submitted. Available on arxiv.org at Error analysis of tau-leap simulation methods, to appear in Annals of Applied Probability. [7] David F. Anderson and Masanori Koyama, Weak error analysis of numerical methods for stochastic models of population processes, Submitted. Avai...

The problem of inference for the proportion of successes in a finite populations is given much less attention in both inference and application courses than the related infinite population problem. However, the finite population problem is both interesting and useful in its own right while also providing insight into various approaches for the infinite population case. This article explores exa...