title: Evolution of bioconvective patterns in variable gravity.
abstract: Measurements are reported of the evolution of bioconvective patterns in shallow, dense cultures of microorganisms subjected to varying gravity. Various statistical properties of this random, quasi-two-dimensional structure have been found: Aboav's law is obeyed, the average vertex angles follow predictions for regular polygons, and the area of a pattern varies linearly with its number of sides. As gravity varies between 1 g and 1.8g (g = 9.8 m s-1), these statistical properties continue to hold despite a tripling of the number of polygons and a reduced average polygon dimension by a third. This work compares with experiments on soap foams, Langmuir monolayer foams, metal grains, and simulations.
authors.affiliation: Universities Space Research Association, NASA Marshall Space Flight Center, Huntsville, Alabama 35812, USA.
authors.forename: D A
authors.initials: DA
authors.lastname: Noever
mesh_terms: D000818:Animals; D055592:Biophysical Phenomena; D001703:Biophysics; D018481:Convection; D056890:Eukaryota / Q000502:physiology*; D006112:Gravitation; D018471:Hypergravity; D008297:Male; D015233:Models, Statistical; D009043:Motor Activity; D013026:Space Flight; D013094:Spermatozoa; D013550:Swimming; D013696:Temperature; D013769:Tetrahymena pyriformis / Q000502:physiology*; D014783:Viscosity; D014893:Weightlessness