Fig. 3
Analysis of the scattered light intensity patterns following a semi-mechanistic approach based on an extended sigmoidal function (a). The extended sigmoidal function consists of five parameters (a-e) and is described by Eq. 1. In this model, a [a.u.] represents the lowest scattered light intensity, b [a.u.] corresponds to the hub of the curve, c [h] is the time of the inflection point (value on x-axis), d [h] is a parameter inversely proportional to the slope of the sigmoidal curve, and e [a.u. h−1] is the linear slope. Exemplarily, measured scattered light intensity signals and model data over time are shown belonging to different classification according to Fig. 2: insufficient induction (b), optimal induction (c) and too strong induction (d). The corresponding model parameters are given in the figure. As reference, the pattern of a non-induced culture is presented