Top, precursor synthesis initiates after injury and lasts for 30 time units; precursors undergo a transit time of 30 units before maturing to a stable product. Middle, injury stimulates production of a precursorPfrom some activated source componentAask1AandPis converted to stable productNask2P, such thatN(t)=A0[1−k2k2−k1e−k1t+k1k2−k1e−k2t].k1= 0.08 andk2= 0.01 depicted. Bottom, regeneration in a turnover scenario where a precursorPis synthesized with ratek1,Pis converted into productNwith ratek2P, andNis degraded with ratekdegN. The condition where the system is at steady state and injury removes a portion ofNbut does not affect the precursors is considered, withP0equal to the steady-state value ofPsuch that thereafterN(t)=k1kdeg(1−e−kdegt)+N0e−kdegt, withk2not impactingN(t)and valuesk1=4andkdeg=0.05shown. In this case, repair can initiate with available precursors without delay.
