Type of Document	Dissertation
Author	Cotton, John Rowland III
Author's Email Address	jcotton@vt.edu
URN	etd-32298-104435
Title	Mechanical modeling of vestibular hair cell bundles
Degree	PhD
Department	Engineering Science and Mechanics
Advisory Committee	Advisor Name Title Batra, Romesh C. Inman, Daniel J. Peterson, Ellengene H. Ragab, Saad A. Grant, John Wallace Committee Chair
Keywords	Hair cell ciliary bundles finite element analysis vestibular sense
Date of Defense	1998-01-30
Availability	unrestricted
Abstract Hair cells are transducers found found in the inner ear of vertebrates. They convert a mechanical signal, detected by the deflection of a bundle of cilia extending from their top surface, into an electrochemical signal. This dissertation studies the mechanical influence of the structure and materials on the function of the cells. I introduce two methods to conduct the mechanical analysis. The first uses strength of materials formulae to solve the simplified hair cell bundle models. The second is a finite element analysis, used to better account for the observed complexity of the structure. I then use these two techniques to build a fundamental understanding of the hair cell bundle structure. By first studying simplified models, then adding complexity, the effects of geometric and material variation can be deduced. I then study three actual bundles. These are all taken from vestibular organs of turtles, two from the posterior semicircular canal and one from the utricle. I present estimations of stiffness, tip link tensions, and nonlinear response. Finally, I investigate a single cilium forced by a fluid flow. The problem is solved by finite difference technique. Three different initial conditions are solved.
Files	Filename       Size       Approximate Download Time (Hours:Minutes:Seconds)     28.8 Modem   56K Modem   ISDN (64 Kb)   ISDN (128 Kb)   Higher-speed Access    APP_A.PDF 22.24 Kb 00:00:06 00:00:03 00:00:02 00:00:01 < 00:00:01   APP_B.PDF 20.64 Kb 00:00:05 00:00:02 00:00:02 00:00:01 < 00:00:01   APP_C.PDF 8.31 Kb 00:00:02 00:00:01 00:00:01 < 00:00:01 < 00:00:01   APP_D.PDF 15.27 Kb 00:00:04 00:00:02 00:00:01 < 00:00:01 < 00:00:01   BIB.PDF 11.17 Kb 00:00:03 00:00:01 00:00:01 < 00:00:01 < 00:00:01   CHP1.PDF 40.77 Kb 00:00:11 00:00:05 00:00:05 00:00:02 < 00:00:01   CHP2.PDF 114.23 Kb 00:00:31 00:00:16 00:00:14 00:00:07 < 00:00:01   CHP3.PDF 147.54 Kb 00:00:40 00:00:21 00:00:18 00:00:09 < 00:00:01   CHP4.PDF 95.94 Kb 00:00:26 00:00:13 00:00:11 00:00:05 < 00:00:01   CHP5.PDF 67.65 Kb 00:00:18 00:00:09 00:00:08 00:00:04 < 00:00:01   COVER.PDF 8.85 Kb 00:00:02 00:00:01 00:00:01 < 00:00:01 < 00:00:01   Vita.pdf 4.06 Kb 00:00:01 < 00:00:01 < 00:00:01 < 00:00:01 < 00:00:01

If you have questions or technical problems, please Contact DLA.