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C D Geisler

Publications and source records attributed to C D Geisler.

67 records · Page 4Linked to original sources

A model of the peripheral auditory system responding to low-frequency tones.

A model of the peripheral auditory system responding to low-frequency tone stimulation is given. The model is of the type previously introduced by Weiss (1966). It includes three interconnected parts: a linear model of the ear's mechanical system, a model of the cochlear transducer, and a stochastic model of an auditory nerve fiber. The output of the model accurately mimics many characteristics of the output of some auditory nerve neurons responding to sinusoidal stimuli but is unable to successfully match all reported aspects of data obtained from other of these neurons. Characteristics of the model neurons are discussed.

Cochlea↗

Guinea pig tectorial membrane profile in an in vitro cochlear preparation.

The guinea pig cochlea was examined under high-magnification light microscopy in an in vitro preparation. After extraction of the otic capsule, the bulla was opened widely and a small hole made into the fourth turn of the scala vestibuli. The organ of Corti was visualized under artificial endolymph at 600 X magnification. Added 1-micron titanium dioxide particles settled on the upper surface of the transparent tectorial membrane. Particle positions showed that much of this upper surface lay in a flat sheet that extended centrifugally almost to the Hensen's cells, giving the impression it was attached there. The sheet extended at least to the level of the inner hair cells, where a tectorial membrane thickness of about 40 micron was reached. Titanium dioxide particles were seen regularly in immediate proximity to the hair cell cilia, indicating that scala media is continuous with the subtectorial space. Upon mechanical manipulation, Hensen's cells proved to be extremely cohesive and elastic. It is suggested that hair cell stereocilia provide major mechanical connections for the tectorial membrane.

Animals↗

A study of hospital based ambulance systems in Wisconsin.

This study was undertaken to determine the advantages and disadvantages of a hospital-based emergency medical service system with hospital employees serving as emergency medical technicians. This type of service is operating in thirteen hospitals in Wisconsin. A series of interviews was conducted to obtain pertinent information regarding the hospital, emergency medical vehicles, ambulance attendants, finances, communications and personal reactions to the system. The data indicate that hospital-based services using hospital employees can operate with minimal interference to regular patient care, and with apparent advantages to the emergency patients. In the rural, sparsely populated areas which were studied, response times from the hospital-based systems were comparable to other rural systems, and the financial and administrative aspects of the system were reviewed.

Allied Health Personnel↗