The Zero-stress State of the Gastrointestinal Tract. The Concept of Residual Stress and Strain
The function of the gastrointestinal tract is to propel food by peristaltic motion, which is a result of the interaction of the tissue forces in the wall and the hydrodynamic forces in the food bolus. To understand the tissue forces in the gastrointestinal tract, it is necessary to know the stress-strain relationships of the tissues. The stress-strain relationships must be measured with reference to the zero-stress state (the condition where neither external nor internal forces deform the tissue). The basic equations for computing stress and strain are given in Chapter 3. The zerostress state of the tissue constitutes the standard state for describing tissue morphology because the tissue is not deformed by internal and external forces. The residual stress and strain cannot be assessed if the zero-stress state is not known, hence the determination of the zero-stress state of gastrointestinal tissue is the first step in the determination of the mechanical properties.
KeywordsLuminal Dinate EGTA
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- Dou Y, Zhao J, Gregersen H. 2002. Morphology and stress-strain distribution along small intestine in the rat. J Biomech Eng, in press.Google Scholar
- Fung YC. 1983. What principle governs the stress distribution in living organs? In: Biomechanics in China, Japan and USA, ed. Fung YC, Fukada E, Junjian W, pp. 1–13. Beijing, China: Science.Google Scholar
- Fung YC. 1990. Biomechanics: Motion, Flow, Stress, and Growth. New York: Springer-Verlag.Google Scholar
- Fung YC. 1993. Biomechanics: Mechanical Properties of Living Tissue. New York: Springer-Verlag.Google Scholar
- Gabella G. 1987. Structure of muscles and nerves in the gastrointestinal tract. In: Physiology of the Gastrointestinal Tract, ed. Johnson LR, Christensen J, Jackson MJ, Jacobson ED, Walsh JH, pp. 335–82. New York: Raven Press.Google Scholar
- Gregersen H, Lee C, Chien S, Skalak R, Fung YC. 1999. Strain distribution in the layered wall of the esophagus. J Biomed Eng, 121: 442–8.Google Scholar
- Omens JH. 1988. Left ventricular strain in the no-load state due to the existence of residual stress. PhD thesis, Department of Bioengineering, University of California, San Diego.Google Scholar
- Vaishnav RN, Vossoughi J. 1983. Estimation of residual strains in aortic segments. In: Biomedical Engineering IL Recent Developments., ed. Hall CW, pp. 330–3. New York: Pergamon Press.Google Scholar