Jeremy A. Brown

Learn More
The results of a study of the three-dimensional vibration of two dry human skulls in response to harmonic excitation are presented. The vibratory response exhibits three distinct types of motion across the range of audible frequencies. At low frequencies below 1000 Hz, whole-head quasi-rigid motion is seen. At the middle frequencies between 1000 and 6000(More)
OBJECTIVE To evaluate optimal placement of the Floating Mass Transducer of the Vibrant Soundbridge (Med-El, Innsbruck, Austria) against the round window membrane, particularly the impact of interposed coupling fascia and of covering materials. METHOD : Six fresh human cadaveric temporal bones were used. After mastoidectomy, posterior tympanotomy and(More)
The bone-anchored-hearing-aid (BAHA) transduces airborne sound into skull vibration. Current bilateral BAHA configurations, for sounds directly facing listeners, will apply forces that are in-phase with each other and directed roughly towards the center of the head. Below approximately 1000 Hz the two cochleae respond in approximately the same direction and(More)
Field observations were conducted on four species of nesting male centrarchids to determine if guarding males discriminate intruders with respect to their potential threat to the brood, their size or position in the water column, or by the stage of the nest. Results demonstrated that bluegill (Lepomis macrochirus) and pumpkinseed (L. gibbosus) sunfish were(More)
Digital transmit and receive beamformers for a 45-MHz, 7-element annular array are described. The transmit beamformer produces 0- to 80-Vpp monocycle pulses with a timing error of less than +/-125 ps. Up to four adjustable transmit focal zones can be selected. The dynamic receive beamformer uses a variable frequency sampling technique in which the frequency(More)
Relatively little work has been done on the ontogeny of feeding behaviour in fish. One of the aims of this study was to compare the ontogeny of feeding behaviour in four species of centrarchid fish of diverse feeding guilds. A second aim was to test Mayr's hypothesis that the locomotory acts involved in the ontogeny of feeding behaviour would be(More)
OBJECTIVE To compare the performance of a subcutaneous piezoelectrically actuated hearing aid (SPAHA) with the bone-anchored hearing aid (BAHA) and assess its effectiveness as a treatment option for conductive loss and single-sided deafness (SSD). BACKGROUND To validate the use of the SPAHA as a bone conduction implant, its performance was compared with a(More)
Imaging techniques currently used in the clinic to inspect ears in patients are generally limited to views terminating at the tympanic membrane (TM) surface. For imaging past the TM, methods such as computed tomography are typically used, but in addition to disadvantages such as being costly, time consuming, and causing radiation exposure, these often do(More)
Ultrasonic power transfer using piezoelectric devices is a promising wireless power transfer technology for biomedical implants. However, for sub-dermal implants where the separation between the transmitter and receiver is on the order of several acoustic wavelengths, the ultrasonic power transfer efficiency (PTE) is highly sensitive to the distance between(More)
Ultrasonic power transfer is a promising alternative to electromagnetic induction for providing wireless power to active implanted medical devices. In a portable ultrasonic power link for devices like cochlear implants, there is a key requirement for an inverter circuit that is capable of driving the transmitting piezoelectric transducer with high(More)