Dependence of lagtime on activator size. (a) All simulations were carried out as in Fig. 1, except for the difference in activator size. Wall shear rate is 17s-1. The inset shows the dependence in a semi-reciprocal scale. (b) 1) normal case, activator size 500 μm; 2) activator size 500 μm, no convection of all enzymes except for factors IIa and Xa; 3) normal case, activator size 1000 μm.