Figure 3: Measurement of viscous moduli via sinusoidal analysis in pig tissue. (a) The frequency sweep perturbation is imparted after a 90-second hold at SL of 2.15 or 2.25 μm. The viscous modulus is calculated utilizing the magnitude of the stress response, magnitude of the length perturbation and phase delay (schematic, right). (b) The viscous modulus measured in control tissues at SL of 2.15 μm (CTRL, black) is reduced in the presence of recombinant PEVK proteins (+PEVK, gray) by 40%. (c) At a SL of 2.25 μm, adding PEVK protein (+PEVK, gray) reduces the viscous modulus at all frequencies. * indicates across the frequencies noted by the horizontal bar. See text for details.