Fig. 2a: Staphylococcus aureus strain 1 reproduction or kill rate R[C, t] as a function of time t and meropenem concentration C, calculatd with  "complete", "adaptation" and MIC models. Parameters used, i.e. eqs. (16, 16m), are the ones that give best experimental fits. Lower part of figure shows cross sections through upper part at t = 1 and t = 3 h. MIC[t = 1 h] = 0.029 mg/l, MIC[t = 3 h] = 0.024 mg/l has been determined in Fig. 6 .

Note that at C >> EC50  the Emax model curves lie below the (dashed) MIC model curve, in particular

• for small times  (t = 1 h) both Emax model curves are below -R₀,
• for larger times (t = 3 h) mostly the adaptation Emax model curve lies below -R₀.

R[C = 0] = R₀ = 0.33 /h.

To fit the experiments one needs to assign such counterintuitive Emax model rates R (Mattie et al., Mouton et al. 1997, Vinks et al, 2004].

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