title: Rhythmic biological systems under microgravity conditions.
abstract: Rhythmic phenomena in biology cover a wide frequency spectrum.  In Space, the rhythms will encounter microgravity conditions which can, therefore, be a valuable tool for their understanding.  A review and discussion of important effects of gravity/absence of gravity on biological systems will be given.  Convection will be emphasized as a mechanism which is drastically reduced in Space.  Microgravity might also affect the coupling between individual oscillators in a multi-oscillatory system.  The environmental interference with rhythms will be discussed with a simple feedback as a starting point.  Model simulations will be presented and clinostat and microgravity-conditions will be discussed in a specific case, viz.  the gravitropical system of plants which can show sustained oscillations.
authors.affiliation: Department of Physics, AVH University of Trondheim, Dragvoll, Norway.
authors.forename: A
authors.initials: A
authors.lastname: Johnsson
authors.forename: T
authors.initials: T
authors.lastname: Eidesmo
mesh_terms: D002940:Circadian Rhythm / Q000502:physiology*; D018481:Convection; D005246:Feedback / Q000502:physiology*; D018522:Gravitropism / Q000502:physiology; D008954:Models, Biological; D009991:Oscillometry; D010944:Plants; D013026:Space Flight; D013696:Temperature; D014893:Weightlessness