INS and type 1 diabetes mellitus: In fact, if one simulates plasma insulin concentration after a bolus injection of U-400 regular insulin using the proposed IP model vs. the same amount of insulin after a bolus of U-100 fast-acting insulin using the SC model incorporated into the UVa/Padova T1D Simulator [15], one can observe a faster appearance/disappearance of plasma insulin after IP vs. SC administration (Figure 4).