Example of an isotropic cube. Orthogonal views
(A) pre- and (B)
post-expansion. Scale bars: 5 μm. (C) Distribution of the expansion
factors calculated for each corresponding pixel line in the x-, y-, and z-dimensions
for the example shown in (A) and (B). Lines represent median values.
In z-dimension, we clearly see a broader distribution
for the expansion factor, as the resolution in this dimension is typically
lower. Single outliers that originate from the pixels at the borders
of the square that were below 2 and above 10 were removed, as they
are not representative of the actual expansion factor. Outliers that
originated from pixel lines in the middle of the square were never
removed. (D) Size, median value, and median absolute deviation (MAD)
of the sample distributions plotted in (C).