Instability and `Sausage-String' Appearance in Blood Vessels during High   Blood Pressure
  A new Rayleigh-type instability is proposed to explain the `sausage-string' pattern of alternating constrictions and dilatations formed in blood vessels under influence of a vasoconstricting agent. Our theory involves the nonlinear elasticity characteristics of the vessel wall, and provides predictions for the conditions under which the cylindrical form of a blood vessel becomes unstable. 
Preben Alstrom (1), Victor M. Eguiluz (2), Morten Colding-Jorgensen   (3), Finn Gustafsson (4) and Niels-Henrik Holstein-Rat...