Fig. 8.

Comparison of the dynamical responses to a transient increase in the amplification factor by three different frameworks capable of modeling cells with variable lifespans and amplification factor: ODE with external amplification (ODE EA; ); ODE with age classes (ODE AC; ); and discrete recursive equation (DRE; ) with age classes. All models were set up with as much equivalence as possible (see Text). Panel A shows the simulation results for the total numbers of cells for all frameworks. Panels B and C show the numbers of cells in each age class of the ODE and DRE frameworks, respectively. These are shown with a color gradient from black (first age class) to light gray (sixth age class). The frameworks with age classes performed very similarly to each other, while the ODE with external amplification is a reasonably good approximation of the frameworks with age classes, considering that this framework consists of only one differential equation.