This paper introduces the class of reflected number systems. Members of this class have the adjacency property, i.e. representations for consecutive numbers differ in only one digit and the magnitude of this difference is one. It shows that every number system based on a positional weighting scheme has a reflected analogue. It presents procedures to convert a number system to its reflected anal...

Book Reviews another way to teach science—smaller, less spectacu-Telling the True Story of Biology lar, and until now, less-respected by the marketplace. That other way is to tell stories. I am convinced that all great teachers (and the Ameri-Discovery—Windows on the Life Sciences can scientific community has had its share), are storytell-By R.A. Lewis ers. I would also suggest that the most su...

This paper contains the motivation for the study of critical surfaces in [2]. In that paper, the only justification given for the definition of this new class of surfaces is the strength of the results. However, when viewed as the topological analogue to index 2 minimal surfaces, critical surfaces become quite natural.