Fig. 2.
Independent component (IC) 1 (solid) and IC2 (dashed) signals (a) and weights (b) obtained from the 2 × 10−2% AO stain followed by 3 washing cycles data set (N = 39, n = 113). Note that the 107 CFU ml−1 samples are absent from this independent component analysis since the signal was saturated. IC1 (solid) and IC2 (dashed) signals (c) and weights (d) obtained from the 2 × 10−3% AO stain followed by 2 washing cycles data set (N = 32, n = 76). Samples in (c) and (d) are coloured by concentration following the colour scheme of Fig. 1 and use the following symbols: upward-pointing triangle 108, left-pointing triangle 107, diamond 106, square 105, asterisk 104, circle 103, cross 102, plus sign 0 CFU ml−1.