FIG. 1.

(A) Reaction cell with the biofilm held in place by agar. MRI measurements were of 14 contiguous slices, perpendicular to flow. (B) For each slice, 64 T₂-weighted images are acquired with increasing echo time. (C) For each pixel, the decay of the MRI signal can be fitted to an exponential function, giving a T₂ value. Taking the T₂ values for each pixel yields a T₂ parameter map. The approximate scale (height) of a biofilm is 1 cm. Relative dimensions are not exact.