ExploringC omputer programs, like many other dynamic and abstract processes, are often best understood by observing graphical simulations of their behavior. Graphical displays of a program in action expose some properties that we might otherwise find difficult to understand or even notice. Moreover, this communication medium becomes even more powerful if we interact with such animations by controlling both the program being simulated and the uay information is presented. Algorithm animation environments follow this paradigm for exploring computer programs.With the advent of workstations in the past five years or so, a handful of algorithm animation systems have been developed and used for a variety of applications. For example, at Brown University, Brown's and Sedgewick's Balsa was used for instruction in computer science courses (in particular, introductory programming, data structures, and graphics) and for research in the design and analysis of algorithms.' London and Duisberg at Tektronix used animated programs for performance tuning and debugging of large systems,2 and at Bell Labs, Bentley and Kernighan exploited animated displays for algorithm research and for generating sequences of static diagrams of

No abstract

This is the first study to indicate the incidence of clear cell change among colorectal adenomas. It has confirmed high proliferative activity within the clear cell portion of colorectal adenomas.

No abstract

The production of NO was increased in patients with perennial nasal allergy, but the blood flow in the nasal mucosa of patients was reduced. Nitrotyrosine formation suggests that there is a process of ONOO(-)-induced damage in mucosa of patients with the perennial nasal allergy and this damage may limit the dilatation of blood vessels, despite the presence of excessive NO.