The development of human exposure standards for radio-frequency fields.

Biological effects and health implications of radio frequency (RF) electromagnetic fields have been a subject of scientific investigation for more than 50 years. It has become a focus of attention because of the expanded use of RF radiation in the frequency range between 300 MHz and 6 GHz for wireless communication over the past decade. Another cause for the attention is the uncertainty of some observed responses and lack of understanding of the mechanism of interaction of RF electromagnetic fields with biological systems.

Pupil noise is a discriminator between narcoleptics and controls.

The pupil light reflex has a long history of being able to indicate states of mental arousal, ranging from sleepiness to concentrated cognitive effort. Such mental states have usually been inferred from pupil diameter or pupil area movements relative to some reference; sleepiness, for example, is characterized by a smaller than average pupil while mental effort brings on a slightly larger pupil. But all pupil movements and associated states of arousal are accompanied by a persistent random pupil diameter motion which has previously been attributed to neurological noise, the noise apparently arising in the neurological controller of the pupil reflex control system.

Neurological pupillary noise in narcolepsy.

Pupillometry has a long but inconclusive history as a means of measuring human alertness. Spontaneous pupillary oscillations in narcoleptics and the sleep deprived are a recognized but quantitatively elusive indication of alertness. Stimulation of the pupillary light reflex (PLR) has provided contradictory or confusion indications of alertness levels.

An auditory localization model based on high-frequency spectral cues.

We present in this paper a connectionist model that extracts interaural intensity differences (IID) from head-related transfer functions (HRTF) in the form of spectral cues to localize broadband high-frequency auditory stimuli, in both azimuth and elevation. A novel discriminative matching measure (DMM) is defined and optimized to characterize matching this IID spectrum. The optimal DMM approach and a novel back-propagation-based fuzzy model of localization are shown to be capable of localizing sources in azimuth, using only spectral IID cues.

The cap-choke catheter antenna for microwave ablation treatment.

A matched-dipole type catheter antenna is described for intracavitary and/or transluminal microwave treatment of diseases that may be responsive to thermal ablation therapy. This cap-choke antenna consists of an annular cap and coaxial choke design that can yield SAR distributions in and can produce heating of tissue surrounding the distal end of the catheter antenna. The cap-choke antenna is simple in construction, provides the desired specific absorption rate (SAR) distribution, and is efficient, i.

Microwave ablation of the atrioventricular junction in open-chest dogs.

The use of microwave energy for ablation of the atrioventricular (AV) junction was examined in open-chest dogs. Using a specially designed microwave catheter and a 2450 MHz generator, microwave energy was delivered to the AV junction according to one of two protocols. In protocol 1, increasing amounts of energy were delivered until irreversible AV block occurred.

On the limitations of automated restriction mapping.

Eight important restriction mapping programs, developed between 1978 and 1993, are analyzed and their performance evaluated. The analyses concentrate on the practical value of the programs to molecular biologists who do restriction mapping on a daily basis, rather than on theoretical efficiency. Although all of the programs could find maps consistent with the data, none were able to discriminate reliably the true map from the other consistent maps, given realistic levels of error.