Ordingly, fiber bridges have been explicitly placed on this plane using a
Ordingly, fiber bridges have been explicitly placed on this plane using a uniform spacing, and modeled using the constitutive behavior described by bridge failure model (see the inset of Fig. S1). Also, contribution of matrix towards failure response from the ATA tissue was taken to become negligible, hence Gmatrix = 0. As the dissection spanned the complete width w with the specimen, the fiber bridges were reported with regards to numbers N per unit length inside the dissection propagation direction, where N = nw. Delamination strength Sd in Extended and CIRC directions have been obtained from experimental final results reported by Pasta et al. (2012). Uf was treated because the free parameter in our model, and we estimated it from experimentally obtained peel tension curves in the Lengthy direction (Pasta et al., 2012) making use of appropriate NLR from Table 1. Least-squares curve fitting approach was utilized for this goal. We hypothesized that Uf, being the power expected for any fiber bridge to fail, would be independent of dissection direction. Consequently, we employed these estimated values of Uf in conjunction with appropriate NCR from Table 1 to predict peel tension in CIRC direction.3. ResultsFig. 4(a) shows representative delamination curves from simulated tests for 3 situations with distinctive numbers of fiber bridges per unit length, N. The initial rising part of the curve ERK5 supplier corresponded towards the stretching of peel arms. Once the dissection began propagating, the average peel tension P remained basically constant and corresponded to the delamination strength Sd on the specimen. The nature with the simulated curves agreed qualitatively withJ Biomech. Author manuscript; offered in PMC 2014 July 04.Pal et al.Pagethose determined experimentally (Pasta et al., 2012). Fig. 4(b) shows the delamination curves for different fiber failure energy Uf. These two figures revealed that Sd depends strongly on both N and Uf. Even though these curves appeared smooth, a zoomed-in view in Fig. four(a) (inset) shows the presence of fine ale oillations arising. The impact of fiber bridge model parameter Fmax on Sd maintaining N and Uf constants is shown in Fig. four(c). Note that Sd remained essentially unchanged, along with the curves differed only at the initiation region from the plateau. The effect of other fiber bridge model parameters was studied in detail, and is presented within the Supplementary information (SI). Figs. five and 6 demonstrate representative collagen fiber arrangement in CIRC AD and Long AD planes, respectively, as obtained by multi-photon microscopy (Tsamis et al., 2013). These images clearly showed the presence of undulating radially-running fiber components. Simulated peel force curves for the Long direction are depicted in Fig. 7(a and b) together with experimentally observed ones (Pasta et al., 2012) from two representative ATA specimens. A least-squares-based parameter estimation approach yielded the values of Uf as 0.0281 0.0072 Jm and 0.0096 0.0022 Jm, for two ATA specimens. Fig. 8(a and b) presents our model-predicted delamination curves utilizing these values of Uf, in conjunction with the experimental information for CIRC direction. We observed that our predictions agree favorably with all the experimentally evaluated Sd for every single patient in CIRC direction, demonstrating the model’s great predictive capability.EGFR/ErbB1/HER1 web NIH-PA Author Manuscript NIH-PA Author Manuscript NIH-PA Author Manuscript4. DiscussionEarlier biomechanical studies on dissection of arterial wall (Gasser and Holzapfel, 2006; Pasta et al., 2012; Sommer et.
