A variety of examples are given from different areas of biology to illustrate the general applicability of matrix algebra to discrete models. These models of biological systems are concerned with relations between processes occurring in discrete time intervals. Diffusion, ecosystems, and different types of cells are modeled. (KR/Author)

The paper presents a matrix describing a conceptual framework for a career development education program which values individual differences and leads to economic visibility for all persons. The matrix is intended to guide career educators as they deal with individual differences in program development and delivery. (MF)

Because of the rising real cost of energy, geographic patterns that have dominated the contemporary metropolitan landscape are in a state of change. A conceptual model of the contemporary and future metropolitan landscape is presented to stimulate thought about the changes which may evolve in the spatial organization of urban regions as the real…