Figure 2.

Rheological experimental setup: (A) human colon samples were cut to a diameter of 20 mm and placed on sand paper. Tension and compression were caused by applying force in a direction perpendicular to the tissue samples. Sample stress as a function of axial deformation and time, storage modulus and loss modulus as a function of axial strain, and axial stress and shear strain as well as changes of phase shift as a function of shear strain were measured; (B) viscoelastic behavior of the sample (as a sinusoidal function versus time with phase shift between them); (C) stresses applied to the sample: shear forces (in combination with tissue compression, axial stress) were applied by rotating the upper plate in a direction parallel to the sample.