Schematic representation of the assumed relationships between proliferating fibroblasts (PF), quiescent fibroblasts (QF) and extracellular matrix (ECM) during dermal maturation. PF self-replicate with rate κ1. PF and QF can switch among them with rates κ2 and κ-2 respectively. QF deposit ECM at rate κ3. ECM promotes the switch from PF to QF at rate κ4. (B) System of ordinary differential equations (ODE) describing the process of dermal maturation. Because the system is dynamic, all entities can decay over time (κ6 is the degradation rate of QF, κ7 is the degradation rate of ECM, κ5 is the degradation rates of PF and is incorporated into β as β = κ1GF - κ2 - κ5 where GF stands for the Growth Factors we assume exist). 