This volume is a collection of papers on various areas of current interest in mathematical biology, such as epidemic disease modeling, including the effects of vaccination and strain replacement; immunology, such as T-Cell dynamics and the mechanism of phagocytosis; knot theory; DNA computation; and Boolean networks.Contents:Methylation of DNA may be Useful as a Computational Tool: Experimental Evidence (S Gal et al.)Dynamics of Random Boolean Networks (J F Lynch)Unknots and DNA (L H Kauffman & S Lambropoulou)Developing a Mathematical Model of Phagocytosis: A Learning Process (N Macura et al.)An Age Structured Model of T-Cell Populations (B Kohler)Modeling and Simulation of Age- and Space-Structured Biological Systems (B P Ayati)Nutrient-Plankton Interaction with a Toxin in a Variable Input Nutrient Environment (S R-J Jang & J Baglama)On the Mechanism of Strain Replacement in Epidemic Models with Vaccination (M Martcheva)Readership: Researchers, graduate students in mathematics, mathematical biology and computer science.