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Probably the best-kept travel secret in the great state of South Carolina is Edisto Island and its surrounding geography. This consists of a barrier island with a truly pristine ocean [...]

The very best and most popular golf circuit in existence, attracting the vast majority of top professionals from all over the world, is right here in the United States. The [...]

For 31 years, on the weekend closest to the Fourth of July, the citizens of Smithville, Tennessee, have hosted the most foot-stomping Fiddlers Jamboree spectacular in the South. For two [...]

We have obtained data on the frequency of aggregates of different size classes and on the maximum aggregate diameter of lymphoid cells subjected to aggregation in the laminar shear field of a Couette viscometer. Maximum aggregate diameter reached a plateau level during aggregation. This plateau is considered to be the result of a balance between the hydrodynamic shear forces tending to resist the formation of aggregates, and the adhesive forces of the aggregated cells tending to resist dissociation. Stepwise-increases in the shear rate produced aggregates of progressively smaller maximum diameter until the limiting (i.e. control equivalent) diameter was reached. Equations governing these stepwise changes in aggregate diameter were obtained by regression analysis, and an estimate of the force of dissociation (FD) was made from derived values of the critical shear rate. Thymocytes (FD=2.54 X 10(−6) N m-2/cell) were found to be more adhesive than lymphocytes (FD=2.05 X 10(−6) N m-2/cell), in agreement with current concepts. The observed data on aggregate frequency were seen to be of poor fit with a model of aggregation derived by collision analysis of the aggregation process. This led us to consider the possibility that all cells may not share the same probability of forming an adhesion. We thus derived further models of aggregation in which some fraction of the total cells was considered to have enhanced possibilities of a collision producing an adhesion. Of the models we considered, a 15% preferred fraction offered best agreement with the experimental observations. We therefore conclude that the populations of cells studied in this report are not ‘homogenous’ in that some cells are more adhesive than others. Alterations in the percentage of the preferred fraction of cells will lead to different aggregate-frequency indices. Such changes might be expected to occur during the initial stages of carcinoma development.

Presents an interview with the fictional character Dr. Eartha Quake. She discusses some facts about the earth and earthquakes. INSET: Tremor tidbits..

Presents a fifth grade student's journal highlighting experiences during a week in May 1988, while attending the outdoor school, `Expedition Yellowstone,' held at Yellowstone National Park. Mammoth Hot Springs; Wildlife; Summer 1988 fires at Yellowstone; Re-visit one year later reveals park's regeneration.