James L. Lords

Optical temperature probe

A temperature probe measures temperature changes of biological tissue whilehe tissue is being irradiated with microwaves. The temperature probe is completely nonmetallic to minimize perturbation of the microwave field, and the structure of the probe includes a plurality of optic fibers which carry light to and from a reflective liquid crystal film. The liquid crystal is enclosed in a housing at the tip of the probe which is in contact with the biological tissue, and the liquid crystal undergoes changes in absolute reflectance proportional to the temperature changes of the tissue. The optic fibers are gathered in a bundle with a first portion of the bundle transmitting light from a light generation device to the liquid crystal and the remainder of the bundle transmitting reflected light from the crystal back to a photo transistor. The reflected light received by the photo transistor is converted into an electrical signal and displayed as a representation of temperature.

Acute cadmium toxicity studies upon nine species of aquatic insects.

Abstract Continuous-flow bioassays were employed to determine 96-hour median tolerance limits (TLm), for the stonefly, Pteronarcella badia (Hagen) (TLm was 18.0 mg Cd/l) and the mayfly, Ephemerella grandis grandis Eaton (TLm was 28.0 mg Cd/l). Ninety-six hours TLm values for other species of aquatic insects tested were not determined, since these species were relatively insensitive to cadmium. Insects exposed for four days in cadmium-containing water, then placed in tap water, show a linear rate of cadmium loss. This loss may lower or prevent mortality under ideal conditions.

A Nonperturbing Temperature Sensor for Measurements in Electromagnetic Fields

ABSTRACTAn electro-optical temperature measuring device which neither perturbs electromagnetic fields nor causes hot spots has been developed for use in monitoring temperature in biological systems during microwave irradiation.

Rate Effects in Isolated Turtle Hearts Induced by Microwave Irradiation

Microwave irradiation at 960-MHz CW of isolated poikilothermic hearts in Ringers solution causes bradycardia. Tachycardia is usually produced by generalized heating, suggesting the possibility of a different mechanism in this case. The effect occurs only over a narrow power range of approximately 2-10 mW/g absorbed by the heart. It is hypothesized that microwave radiation causes neurotransmitter release either by excitation of the nerve remnants in the heart, or by some other mechanism, producing bradycardia over a restricted range of power absorption. Drugs which can change the response of the heart to transmitter substances have been used, and the results support a neurotransmitter release hypothesis. A generalized heating effect, causing tachycardia, is predominant at higher levels of absorbed power.

Isolation and characterization of a glycoprotein from the stonefly, Pteronarcys californica, which binds cadmium

Abstract The present study reports the isolation and characterization of a cadmium-containing glycoprotein from the water-soluble fraction of an aquatic insect. The isolated glycoprotein contained 0·67% cadmium, 62·1% carbohydrate, and 37·2% protein. The glycoprotein appears to be involved in the detoxification of cadmium, because species insensitive to cadmium contain five times the amount of the glycoprotein as do species sensitive to cadmium.

Physiological and behavioral effects of chronic exposure to 2450-MHz microwaves

Long-Evans male adult rats were exposed for sixteen weeks to 2450-MHz CW microwaves at an average power density of mW/cm2. The resulting dose rate was 1.23 (+/- 0.25SEM) mW/g. The animals were exposed eight hours a day, five days a week, for a total of 640 h in a monopole-above-ground radiation chamber while housed in Plexiglas holding cages. Daily measures of body mass and of food and water intakes indicated no statistically significant effects of microwave irradiation. Biweekly stabilimetric tests immediately after exposure revealed a significant depression of behavioral activity by 15 microwave-exposed rats as compared with 15 sham-exposed animals. Measures of locomotor activity based on revolutions of a running wheel, which were obtained during 12-h periods between each 8-h exposure, showed no significant effect of irradiation. Blood sampled after 2, 6, 10, and 14 weeks of exposure indicated slight alterations of sulfhydryl groups, and of red and white blood-cell counts. Measures of levels of 17-ketosteroids in urine at weeks 1, 5, 9, and 12 of exposure, and mass of adrenals, heart, and liver at the end of the sixteen-week period of exposure, revealed no indications of stress.

Possible Explanation of Fluoride-Induced Respiration in Chlorella pyrenoidosa

Low concentrations of sodium fluoride significantly increase oxygen consumption and total phosphorylated nucleotides in respiring Chlorella pyrenoidosa. Measurements of gas exchange at several pH values indicate that the stimulation is probably related to the undissociated hydrogen fluoride concentration in the suspending media.

Physiological and behavioral effects of prolonged exposure to 915 MHz microwaves.

Long-Evans male adult rats were exposed for 16 weeks to 915-MHz CW microwaves at an average power density of 5 mW/cm2. The resulting dose rate was 2.46 (+/- 0.29 SEM) mW/g. The animals were exposed eight hours a day, five days a week, for a total of 640 h in a monopole-above ground radiation chamber while housed in Plexiglas cages. Daily measures of body mass and of food and water intake indicated no statistically significant effects of microwave irradiation. Measures by activity wheels and stabilimetric platforms of spontaneous locomotion indicate than mean activity levels increased about 25% after microwave exposure, but the findings are doubtful statistical significance (Ps < .10 but > .05). Studies of blood sampled after 2, 6, 10, and 14 weeks of exposure revealed alterations of free sulfhydryls. Measures of levels of urinary 17-ketosteroids at weeks 1, 5, 9, and 12 of exposure, and measures of brain hypothalamic tissue, and of mass of adrenals, heart, and liver at the end of the 16-week period, revealed no significant differences between irradiated and control animals. Cortical EEGs sampled after conclusion of microwave exposures also revealed no significant differences.

Synergism between dissolved oxygen and cadmium toxicity in five species of aquatic insects

Abstract Continuous-flow bioassays were employed to determine the relationship between dissolved oxygen and cadmium upon five species of aquatic insects, as measured by survival and the amount of cadmium found within the insect. Results indicate the toxicity of cadmium increases as the dissolved oxygen concentration increases. This may be explained by an observed increase in the amount of cadmium found in the insect as the dissolved oxygen concentration increases. Oxygen consumption has been reported to increase as the dissolved oxygen concentration increases ( Petty, 1967 ; Ericksen, 1963 ; Fox et al. , 1937 ). In this study, using a fixed cadmium concentration, the amount of cadmium found in the insect also increased with an increase in the dissolved oxygen. Therefore, cadmium absorption may be coupled to metabolism.

Rate Effects in Isolated Hearts Induced by Microwave Irradiation (Short Papers)

Continuous 960-MHz microwave irradiation of isolated poikilothermic hearts in Ringers solution causes bradycardia, in contrast to the tachycardia usually produced by generalized heating. The effect appears to occur only over a narrow power range in the neighborhood of an estimated 3 mW absorbed by the heart. It is hypothesized that the bradycardia is produced by stimulation of the nerve remnants in the heart.