(A) The degree of nonlinearity of the effects of the oxygen tension in breathing gas on the parameters that characterize the indicial responses of the MBP given in Eqs. 6 and 7 and Table 1 is shown. The physical meaning of the parameters are: A, the MBP (unit: cm H2O) at time t = t0; B, the amplitude of the second term (unit: cm H2O per h); BT1, the peak height of the MBP indicial function above A for step ΔpO2 (unit: cm H2O); C, the asymptotic hypertensive MBP above A as t→0 for step −ΔpO2 (unit: cm H2O); D, the asymptotic MBP as t→0 for step increase of ΔpO2 (unit: cm H2O); t0, time of step lowering of pO2 (unit: h); t1, time of step rising of pO2 (unit: h); T1, time constant for MBP rise (unit: h); T2, time constant for MBP asymptote as t→∞ (unit: h). (B) Similar to A except related to the energy of oscillations of the blood pressure about the mean. Mk(t) is the kth-order mean of the E6(t) about the sixth order of MBP. Data are from Table 2.