Compact MRI-optical Scanners
J. G. Georgiadis,* D. Morris,* P. Gorkov
University of Illinois; National Institutes of Health

Recent advances in miniaturization have allowed the design and fabrication of dual modality imaging systems combining magnetic resonance imaging and standard systems using visible light.

Mechanotransduction in the Vestibular Semicircular Canals
E. R. Damiano*
University of Illinois

The vestibular semicircular canal system is a phylogenetically ancient sensory apparatus responsible for transducing angular motions of the head. Fluid-structure interactions in the semicircular canals that result from head rotation give rise to spike initiation in afferent nerve complexes that encode the vestibular nerve. The aim of this research is to study the response dynamics of the semicircular canals. A new mathematical model of canal mechanics is under development that couples an asymptotic theory of pulsatile flow in curved circular ducts to a mechanoelectrochemical model of the charged mucopolysaccharide structures involved in the transduction process.

Single-Cell Locomotion and Thermodynamics
J. G. Georgiadis,* L. Choi
University of Illinois

This project aims at bridging the gap between models and experimental techniques employed in cell biology and applied and fluid mechanics towards the elucidation of basic processes responsible for mammalian cell locomotion. Both haptotactic and chemotactic stimuli will be considered.

The Role of the Capillary Glycocalyx in Microvascular Permeability, Rheology, and Exchange
E. R. Damiano,* D. M. Behrens, F. H. El-Khatib
The Whitaker Foundation, RG-98-0524

Recent theoretical and experimental studies suggest that the capillary glycocalyx, a macromolecular carbohydrate-rich structure on the luminal surface of the capillary wall, is of fundamental importance to capillary resistance, red-cell flux, and microvascular permeability. The primary goal of the theoretical component of this research will be to develop a rigorous multiconstituent mechanoelectrochemical model of the capillary glycocalyx as a foundation for our understanding of the biophysical properties and physiological behavior of this structure. The integrated experimental component of this work will make use of theoretical results to obtain the first in vivo estimates of fundamentally important properties of the glycocalyx.

Thermal Studies in Bioengineering
J. C. Chato*
University of Illinois

Various aspects of thermal behavior of biological materials and systems, particularly the human body, are studied. The work ranges from morphological studies of the blood vessels that affect heat transfer to computer modeling of various organs as well as the entire thermoregulatory system. Typical applications are the prediction of the deep-body temperature in a hot bath, the estimation of the maximum safe touch temperature of a heated surface, and thermal treatment of toenail fungus.