Main Effects Plot Data Means for log (L/W)
Fibronectin Coated
Feature Width (pm) Groove Depth (pm)
024
019
014
0 009
004
5 10 20 smooth 15 50
Figure 4.3 Main Effects Plot of the data means of fibronectin coated unmodified
elastomers at various ridge widths (Feature) and groove depths (Depth)
The main effects plot helps to elucidate which factors and levels play a role in the
system. The more the data changes between levels, the greater the effect. Figure 4.4 is
an interaction plot generated by Minitab that demonstrates the changes at the different
factor levels for fibronectin coated unmodified elastomer. The important point that is
illustrated here is that at the deeper groove depths, the greater the alignment of the nuclei
to the ridges. One-way analysis of variance (ANOVA) and a multiple comparison test
(Tukey, 95% CI) on each depth comparing the different feature widths demonstrate a
significant difference between each level at the 5 [im depth, but only a statistical
difference at 1.5 .im between 5 .im wide ridges and smooth textures. One of the
difficulties in the analysis of these samples is in the fact that for the smooth samples, the
nuclei are not round, but elongated in random directions. The effect of this is to give a