This paper reports on experiments designed to evaluate the performance of the equipotentials backprojection method under conditions modeling those of proposed applications of electrical impedance tomography. Small spherical targets were placed inside a saline-filled tank with dimensions similar to a human torso. Data were acquired with a computer-based… (More)
This paper describes a new approach to reconstruction of the conductivity field in electrical impedance tomography. Our goal is to improve the tradeoff between the quality of the images and the numerical complexity of the reconstruction method. In order to reduce the computational load, we adopt a linearized approximation to the forward problem that… (More)
Streaming potential distributions were measured on the surface of articular cartilage in uniaxial unconfined compression using a linear array of microelectrodes. Potential profiles were obtained for sinusoidal and ramp/stress-relaxation displacements and exhibited dependencies on radial position, sinusoidal amplitude and frequency, time during stress… (More)
Sounds produced by prosthetic heart valves are known to contain diagnostic information regarding the structural and functional integrity of their components. Analog techniques for processing pros-thetic valve phonocardiograms have met with limited success in extracting this information, because of their poor spectral resolution and lack of versatility.… (More)
This paper describes a portable instrument designed to monitor progress accomplished by patients participating in a hand rehabilitation program. The instrument is driven by a microcontroller and features signal conditioning circuits to measure and record the strength and duration of hand contractions. An alphanumeric display provides the patient with… (More)
Isolated cells can be kept in steady-state conditions for very long periods of time when inserted into dialysis microfibers and perifused with a nutrient-containing solution. Using this system, stable 31P NMR spectra have been obtained on dog kidney tubules for a period of 13 h.