Showing papers in "Medical research engineering in 1976"

An electro-acoustical technique for the detection of knee joint noise.

Abstract: Distinguishing acoustical signatures of sound emitted by normal and pathological knee joints are picked up using a double microphone-differential amplifier setup. Extraneous background noise is minimized using the principle of "noise cancellation". Two identical sensitive condenser microphones and an F.M. recorder with flat responses in the audio range were used. Preliminary studies covering normal and diseased knee joints showed that their respective waveforms and spectral patterns are unique and proved to be a promising nondestructive diagnostic tool for early detection of knee joint cartilage damage.

Reception of microwaves by the brain.

Abstract: The question of how pulsed microwaves induce auditory effects in animals and man leads to an examination of the parameters which determine the frequencies of maximum reception by the skull, and the positions of maximum energy deposition within the brain. The interaction of microwaves with a nerve membrane model and with live nerve cells is also discussed, as well as planned experiments to determine the microwave properties of membranes.

The effect of external pressure on skin temperature distribution by thermography.

Abstract: 1) Serial thermograms were taken after the application of various intensities and durations of localized pressure on the medial surface of the human forearm. 2) Thermal response of the body surface to localized pressure was quantified. 3) It was found that usually a time period of between 1 to 3 minutes elapsed before the body surface attained a maximum elevation of temperature from the time the localized pressure is removed. 4) It was found that increased intensity of pressure (5 psi vs. 3 psi) and longer duration (20 minutes vs. 10 minutes) caused larger thermal responses. 5) It is suggested that high resolution medical thermography may eventually become a useful tool in the fitting of prosthetic and orthotic devices and for the prediction of pressure sores formation so prophylactic measures can be started immediately on immobilized patients.

On a non linear describing function for bio-data.

Abstract: The behaviour and handling of a flexible three variable--parameter function is presented, which is suitable for unbiased regression analysis. The function is defined by an intercept, a slope or coefficient and an exponent on the independent variable. Analog and digital problems and solutions are defined. Handling is simple and the program is run without operator intervention. The range of curves include linear, convex, concave and asymptotic forms and can be extended to include sigmoid and parabolic forms. Some application results are presented for different situations.