bluuebunny/crossref_metadata_2025 huggingface dataset:
Accelerated development of spontaneous and benzopyrene‐induced skin cancer in mice exposed to 2450‐MHz microwave radiation
Authors: Szmigielski Stanislaw , Szudzinski Andrzej , Pietraszek Andrzej , Bielec Marian , Janiak Marek , Wrembel Jolanta K.
Published: February 2006

C3H/HeA mice with high incidence of spontaneous breast cancer and Balb/c mice treated with 3,4‐benzopyrene (BP) (by painting of the skin resulting in the development of skin cancer) were irradiated with 2,450‐MHz microwaves (MW) in an anechoic chamber at 5 or 15 mW/cm2 (2 h daily, 6 sessions per week). C3H/HeA mice were irradiated from the 6th week of life, up to the 12th month of life. Balb/c mice treated with BP were irradiated either prior to (over 1 or 3 months) or simultaneously with BP treatment (over 5 months). The appearance of palpable tumors in C3H/HeA mice and of skin cancer in BP‐treated Balb/c mice was checked every 2 weeks for 12 months. Two additional groups of mice were exposed to chronic stress caused by confinement or to sham‐irradiation in an anechoic chamber; these served as controls. Irradiation with MWs at either 5 or 15 mW/cm2 for 3 months resulted in a significant lowering of natural antineoplastic resistance (mean number of lung neoplastic colonies was 2.8 ± 1.6 (SD) in controls, 6.1 ± 1.8 in mice exposed at 5 mW/cm2 and 10.8 ± 2.1 in those irradiated at 15 mW/cm2) and acceleration of development of BP‐induced skin cancer (285 days in controls, 230 days for 5 mW/cm2 and 160 days for 15 mW/cm2). Microwave‐exposed C3H/HeA mice developed breast tumors earlier than controls (322 days in controls, 261 days for 5 mW/cm2 and 219 days for 15 mW/cm2). A similar acceleration was observed in the development of BP‐induced skin cancer in mice exposed simultaneously to BP and MWs (285 days in controls, 220 day for 5 mW/cm2 and 121 days for 15 mW/cm2). The acceleration of cancer development in all tested systems and lowering of natural antineoplastic resistance was similar in mice exposed to MW at 5 mW/cm2 or to chronic stress caused by confinement but differed significantly from the data obtained on animals exposed at 15 mW/cm2, where local thermal effects (“hot” spots) were possible.
Electromagnetic dosimetry in a sitting rhesus model at 225 MHz
Authors: Olsen Richard G. , Griner Toby A.
Published: February 2006

Dosimetric measurements in a 9.5‐kg tissue‐equivalent rhesus model were conducted at 225 MHz using a nonperturbing temperature probe and a gradient‐layer calorimeter. Temperature probe measurements showed deep penetration of electromagnetic energy, and calorimeter experiments showed an average SAR (0.285 W/kg per mW/cm2) that was nearly three times greater than that observed for the same model at 1.29 GHz.
Assessment of the immune responsiveness of mice irradiated with continuous wave or pulse‐modulated 425‐MHz radio frequency radiation
Authors: Smialowicz R. J. , Riddle M. M. , Well C. M. , Brugnolotti P. L. , Kinn J. B.
Published: February 2006

Groups of female BALB/C mice were irradiated with 425‐MHz radio frequency (RF) radiation either continuous wave (CW) or pulse modulated (PM, 1‐ms pulse width, 250 pulses/s). Mice were irradiated in a rectangular strip‐transmission line at average forward powers of 78, 17.7, or 5 W for CW and 17.7, 5, or 1.25 W for PM. The mean specific absorption rate, as measured using twin‐well calorimetry was 7.7 W/kg for a forward power of 70 W. No differences in the mitogen‐stimulated response of lymphocytes or in the primary antibody response to sheep erythrocytes or polyvinylpyrrolidone were observed between irradiated and sham‐irradiated mice, nor between mice exposed to either CW or PM 425‐MHz RF radiation.
Microwave radiation‐induced calcium ion efflux from human neuroblastoma cells in culture
Authors: Dutta S. K. , Subramoniam A. , Ghosh B. , Parshad R.
Published: February 2006

Monolayer cultures of human neuroblastoma cells were exposed to 915‐MHz radiation, with or without sinusoidal amplitude modulation (80%) at 16 Hz, at specific absorption rates (SAR) for the culture medium and cells of 0.00, 0.01, 0.05, 0.075, 0.1, 0.5, 0.75, 1.0, 1.5, 2, or 5 mW/g. A significant increase in the efflux of calcium ions (45Ca2+) as compared to unexposed control cultures occurred at two SAR values: 0.05 and 1 mW/g. Increased efflux at 0.05 mW/g was dependent on the presence of amplitude modulation at 16 Hz but at the higher value it was not. These results indicate that human neuroblastoma cells are sensitive to extremely low levels of microwave radiation at certain narrow ranges of SAR.
Cell membrane temperature rate sensitivity predicted from the Nernst equation
Authors: Barnes Frank S.
Published: February 2006

A hyperpolarized current is predicted from the Nernst equation for conditions of positive temperature derivatives with respect to time. This ion current, coupled with changes in membrane channel conductivities, is expected to contribute to a transient potential shift across the cell membrane for silent cells and to a change in firing rate for pacemaker cells.
System for the exposure of cell suspensions to power‐frequency electric fields
Authors: Kaune W. T. , Frazier M. E. , King A. J. , Samuel J. E. , Hungate F. P. , Causey S. C.
Published: February 2006

A system is described that uses an oscillating magnetic field to produce power‐frequency electric fields with strengths in excess of those produced in an animal or human standing under a high‐voltage electric‐power transmission line. In contrast to other types of exposure systems capable of generating fields of this size, no electrodes are placed in the conducting growth media: the possibility of electrode contamination of the exposed suspension is thereby eliminated. Electric fields in the range 0.02–3.5 V/m can be produced in a cell culture with total harmonic distortions less than 1.5%. The magnetic field used to produce electric fields for exposure is largely confined within a closed ferromagnetic circuit, and experimental and control cells are exposed to leakage magnetic flux densities less than 5 μT. The temperatures of the experimental and control cell suspensions are held fixed within ±0.1°C by a water bath. Special chambers were developed to hold cell cultures during exposure and sham exposure. Chinese hamster ovary (CHO) cells incubated in these chambers grew for at least 48 h and had population doubling times of 16–17 h, approximately the same as for CHO cells grown under standard cell‐culture conditions.
Interaction between electromagnetic fields and cells: Microelectrophoretic effect on ligands and surface receptors
Authors: Chiabrera A. , Grattarola M. , Viviani R.
Published: February 2006

The aggregation between lectins and lymphocyte surface receptors can be affected strongly by a low‐level electric field induced in the cell suspension by a time‐varying magnetic field. One of the possible mechanisms is the microelectrophoretic effect due to the electric field, which influences the distance (in the mean square sense) between charged ligands and receptors when they are about to separate. On a purely theoretical basis, it is shown that, at low frequencies, an externally induced periodic electric field always decreases the mean lifetime of ligand‐receptor complexes. As a consequence, the mitogenic gain obtained by lectin addition to cell suspension is decreased. These results suggest that such a mechanism, if effective, reduces the lectin mitogenic capability and offers a way of handling similar phenomena which have been described for other biological systems.
Effects of acute low‐level microwaves on pentobarbital‐induced hypothermia depend on exposure orientation
Authors: Lai H. , Horita A. , Chou C. K. , Guy A. W.
Published: February 2006

Two series of experiments were performed to study the effects of acute exposure (45 min) to 2,450‐MHz circularly polarized, pulsed microwaves [1 mW/cm2, 2‐μs pulses, 500 pps, specific absorption rate (SAR) 0.6 W/kg] on the actions of pentobarbital in the rat. In the first experiment, rats were irradiated with microwaves and then immediately injected with pentobarbital. Microwave exposure did not significantly affect the extent of the pentobarbital‐induced fall in colonic temperature. However, the rate of recovery from the hypothermia was significantly slower in the microwave‐irradiated rats and they also took a significantly longer time to regain their righting reflex. In a second experiment, rats were first anesthetized with pentobarbital and then exposed to microwaves with their heads either pointing toward the source of microwaves (anterior exposure) or pointing away (posterior exposure). Microwave radiation significantly retarded the pentobarbital‐induced fall in colonic temperature regardless of the orientation of exposure. However, the recovery from hypothermia was significantly faster in posterior‐exposed animals compared to those of the anterior‐exposed and sham‐irradiated animals. Furthermore, the posterior‐exposed rats took a significantly shorter time to regain their righting reflex than both the anterior‐exposed and sham‐irradiated animals.
Operant behavior and colonic temperature of Macaca mulatta exposed to radio frequency fields at and above resonant frequencies
Authors: de Lorge John O.
Published: February 2006

Five food‐deprived rhesus monkeys were exposed to 225‐MHz continuous‐wave, and 1.3‐GHz, and 5.8‐GHz pulsed radiation to determine the minimal power densities affecting performance. The monkeys were trained to press a lever (observing‐response) thereby producing signals that indicated availability of food. In the presence of the aperiodically appearing food signals, a detection response on a different lever was reinforced by a food pellet. Continuous, stable responding during 60‐min sessions developed and was followed by repeated exposures to radiofrequency radiation. The subjects, restrained in a Styrofoam chair, were exposed to free‐field radiation while performing the task. Colonic temperature was simultaneously obtained. Observing‐response performance was impaired at increasingly higher power densities as frequency increased from the near‐resonance 225 MHz to the above‐resonance 5.8 GHz. The threshold power density of disrupted response rate at 225 MHz was 8.1 mW/cm2; at 1.3 GHz it was 57 mW/cm2, and at 5.8 GHz it was 140 mW/cm2. These power densities were associated with reliable increases in colonic temperatures above sham‐exposure levels. The mean increase was typically in the range of 1°C, and response‐rate changes were not observed in the absence of concomitant temperature increases. In these experiments increase of colonic temperature was a much better predictor of behavioral disruption than was either the power density of the incident field or estimates of whole‐body‐averaged rates of energy absorption.
The effects of microwave radiation on avian dominance behavior
Authors: Wasserman F. E. , Dowd C. , Schlinger B. A. , Byman D. , Battista S. P. , Kunz T. H.
Published: February 2006

Seventeen birds from 12 flocks were exposed to microwave radiation under various combinations of power density and duration; three birds from two additional flocks served as sham‐exposed controls. Experiments were conducted outdoors at Manomet, Massachusetts (41°56′N, 70°35′W) under normal winter ambient temperatures. Although irradiated birds maintained their positions within a flock hierarchy with one exception, some appeared to have a change in their level of aggression after exposure.
Formulas for preparing phantom muscle tissue at various radiofrequencies
Authors: Chou Chung‐Kwang , Chen Gang‐Wu , Guy Arthur W. , Luk Kenneth H.
Published: February 2006

The dielectric properties of various test samples of phantom tissue were measured using an automated and temperature‐controlled slotted line. The ingredients for phantom materials were determined for simulating high‐water content tissue at 13.56, 27.12, 40.68, 70, 100, 200, 300, 433, 750, 915, and 2,450 MHz. The ingredients consisted of water, TX‐150 (a gelling agent), sodium chloride, and polyethylene powder (200–2,450 MHz) or aluminum powder (13.56–100 MHz). The dielectric constant and conductivity of these materials at different temperatures (15, 22, 30°C) were characterized.
Energy deposition in a model of man in the near field
Authors: Stuchly Stanislaw S. , Kraszewski Andrzej , Stuchly Maria A. , Hartsgrove George , Adamski Daniel
Published: February 2006

The spatial distribution of the specific absorption rate (SAR) was measured in a full‐scale model of man using implantable electric field probes. The model was exposed in the near‐field of linear and aperture antennas at 350 MHz. Effects of the wave polarization, antenna position and antenna gain on the SAR distribution and the average SAR in the whole‐body and body parts are reported.
Active microwave tomographic imaging of isolated, perfused animal organs
Authors: Guerquin‐Kern J. L. , Gautherie M. , Peronnet G. , Jofre L. , Bolomey J. C.
Published: February 2006

The relative transparency of biological materials to high‐frequency electromagnetic waves has encouraged the development of new systems for imaging. This report describes experiments of microwave tomography conducted on a prototype. The object to be analyzed is submerged in water and is illuminated by a plane wave. The total electric field is analyzed by a microwave camera. The recorded data are then processed numerically in order to reconstruct the image that corresponds to the distribution of equivalent currents in a defined plane of a section. Experiments have been conducted on isolated kidneys with and without perfusion. The influence of the perfusing solution temperature has also been studied. These experiments show the potential of this system, especially through the correlation between microwave images and the biological structures. They also confirm previous results concerning spatial resolution and depth of exploration. Finally, the results demonstrate the influence of temperature and support the applicability of this imaging system in non‐invasive thermometry, especially for clinical hyperthermia.
Numerical calculation and measurement of 60‐Hz current densities induced in an upright grounded cylinder
Authors: Kaune W. T. , McCreary F. A.
Published: February 2006

Power‐frequency electric fields are strongly perturbed in the vicinity of human beings and experimental animals. As a consequence, the extrapolation of biological data from laboratory animals to human‐exposure situations cannot use the unperturbed exposure field strength as a common exposure parameter. Rather, comparisons between species must be based on the actual electric fields at the outer surfaces of and inside the bodies of the subjects. Experimental data have been published on surface and internal fields for a few exposure situations, but it is not feasible to characterize experimentally more than a small fraction of the diverse types of exposures which occur in the laboratory and in the field. A predictive numerical model is needed, one whose predictions have been verified in situations where experimental data are available, and one whose results can be used with confidence in new exposure situations. This paper describes a numerical technique which can be used to develop such a model, and it carries out this development for a test case, that of a homogeneous right‐circular cylinder resting upright on‐end on a ground plane and exposed to a vertical, uniform, 60‐Hz electric field. The accuracy of the model is tested by comparing short‐circuit currents and induced current densities predicted by it to measured values: Agreement is good.
The extremely low frequency electrical properties of plant stems
Authors: Hart Francis X.
Published: February 2006

The electrical properties (variation of capacitance and conductance with frequency) of a plant stem can be conveniently measured in vivo by time domain dielectric spectroscopy. In this technique a voltage step is applied to a stem. The resulting polarization current is sampled by a microprocessor and Fourier‐transformed to yield these properties. Spectra were obtained for seven electrode separations along a Poinsettia stem. The inverse capacitance and conductance were plotted vs separation for 50 frequencies from .35 to 350 Hz. Least‐square fits yielded the effective dielectric constant and conductivity of the stem over this frequency range. In this way electrode effects were eliminated. A similar procedure was carried out for Coleus.

A log‐log plot of dielectric constant vs frequency shows a two‐stage linear decrease for both plants. The conductivity is primarily DC. The dielectric loss decreases smoothly with frequency for Coleus. These results are compared to those for bone and the inorganic material hollandite. The dielectric properties seem best described by a cooperative, manybody approach.
Effects of microwave radiation (340 and 900 MHz) on different structural levels of erythrocyte membranes
Authors: Kim Y. A. , Fomenko B. S. , Agafonova T. A. , Akoev I. G.
Published: February 2006

By use of fluorescence probes 1‐anilinonaphthalene‐8‐sulfonic acid, 2‐toluidinylnaphthal‐ene‐6‐sulfonate, pyrene, perylene and chemical label phosphatidylethanolamine 2,4,6‐trinitrobenzele sulfonic acid, the effect of microwave radiation on the erythrocyte membrane was studied. The studies with the fluorescence probes were carried out on erythrocyte ghosts and with 2,4,6‐trinitrobenzene sulfonic acid on whole erythrocytes. The fluorescence was measured during irradiation of the membranes with 340‐MHz microwaves at an SAR of 100 W/kg. Trinitrophenylation of phosphatidylethanolamine from whole erythrocytes was performed simultaneously with microwave irradiation at 900 MHz (10 mW/cm2). It was shown that the microwave field decreased lipid viscosity, altered the structural state of lipid‐protein contact regions, and decreased the protein shielding of lipids. These changes corresponded to those produced by thermal action of microwaves.
A Role for the magnetic field in the radiation‐induced efflux of calcium ions from brain tissue in vitro
Authors: Blackman C. F. , Benane S. G. , Rabinowitz J. R. , House D. E. , Joines W. T.
Published: February 2006

Two independent laboratories have demonstrated that electromagnetic radiation at specific frequencies can cause a change in the efflux of calcium ions from brain tissue in vitro. In a local geomagnetic field (LGF) at a density of 38 microTesla (μT), 15‐ and 45‐Hz electromagnetic signals (40 Vp‐p/m in air) have been shown to induce a change in the efflux of calcium ions from the exposed tissues, whereas 1‐ and 30‐Hz signals do not. We now show that the effective 15‐Hz signal can be rendered ineffective when the LGF is reduced to 19 μT with Helmholtz coils. In addition, the ineffective 30‐Hz signal becomes effective when the LGF is changed to ±25.3 μT or to ± 76 μT. These results demonstrate that the net intensity of the LGF is an important variable. The results appear to describe a resonance‐like relationship in which the frequency of the electromagnetic field that can induce a change in efflux is proportional to a product of LGF density and an index, 2n + 1, where n = 0,1. These phenomenological findings may provide a basis for evaluating the apparent lack of reproducibility of biological effects caused by low‐intensity extremely‐low‐frequency (ELF) electromagnetic signals. In future investigations of this phenomenon, the LGF vector should be explicitly described. If the underlying mechanism involves a general property of tissue, then research conducted in the ambient electromagnetic environment (50/60 Hz) may be subjected to unnoticed and uncontrolled influences, depending on the density of the LGF.
Neuroendocrine parameters in the rat exposed to 60‐Hz electric fields
Authors: Quinlan William J. , Petrondas Demetrios , Lebda Nancy , Pettit Sue , Michaelson Sol M.
Published: February 2006

This study was designed to assess the neuroendocrine response of male Long‐Evans rats to sustained or intermittent 60‐Hz electric fields when exposed for 1 or 3 h at 100 kV/m. No significant differences were noted in corticosterone, prolactin, or thyrotropin levels between exposed and sham‐exposed rats. A statistically significant increase (P < .01) in growth hormone was noted in rats exposed to intermittent electric fields for 3 h. Emphasis was placed on good experimental design and the need to avoid standard laboratory stressors (excessive handling, temperature extremes, transportation, noise, etc.) known to be present in many biomedical studies. The importance of avoiding reactions due to extraneous factors in experiments predicated on investigating physiological function in relation to electric field exposure is discussed.
Possible effects of electric blankets and heated waterbeds on fetal development
Authors: Wertheimer Nancy , Leeper Ed
Published: February 2006

Seasonal patterns were seen in fetal growth and in abortion rate for families using electrically heated beds. These patterns could be attributed to the seasonal use of heated beds. The fact that such seasonal patterns were seen only in users, and not in nonusers, of electrically heated beds suggests that electrical bed heating may have a direct effect on fetal development. The effect could be due to excessive heat or to electromagnetic field exposure.
Behavioral and physiological effects of chronic 2,450‐MHz microwave irradiation of the rat at 0.5 mW/cm2
Authors: D'Andrea John A. , DeWitt John R. , Gandhi Om P. , Stensaas Suzanne , Lords James L. , Nielson Harold C.
Published: February 2006

Adult male Long‐Evans rats were intermittently exposed to 2450 MHz CW microwaves at an average power density of 0.5 mW/cm2 for 90 days. The resulting SAR was 0.14 W/kg (range 0.11 to 0.18 W/kg). The animals were exposed 7 h/day, 7 days/wk, for a total of 630 h in a monopole‐above‐ground radiation chamber while housed in Plexiglas holding cages. Daily measures of body mass and food and water intake indicated no statistically significant effects of microwave exposure. Monthly assessment of reactivity to electric footshock, levels of cholinesterase and sulfhydryl groups in blood, and 17‐ketosteroids in urine revealed no reliable differences between 14 sham‐exposed and 14 microwave‐exposed rats. After the 90 days of exposure, seven rats, randomly chosen from each group, were assessed for open‐field behavior, shuttlebox performance, and schedule‐controlled (IRT schedule) lever pressing for food pellets. Statistically significant differences between microwave‐exposed and sham‐exposed rats were observed in shuttlebox performances and lever pressing. Post mortem measures of mass of several organs and microscopic examination of adrenal tissue revealed no differences between the two groups of animals.
Dielectric properties of lens tissue at microwave frequencies
Authors: Steel M. C. , Sheppard R. J.
Published: February 2006

The relative permittivity and conductivity of rabbit eye lens were measured in the frequency domain between 2 and 18 GHz at temperatures of 37 and 20°C. An analysis of the data suggested that a significant proportion of the bulk water in nuclear and cortical lens tissue may behave differently to pure water. In addition, the Maxwell‐Fricke mixture theory was used to estimate the amount of hydrated water that relaxes far below 1 GHz.
50‐Hz electromagnetic environment and the incidence of childhood tumors in Stockholm county
Authors: Tomenius Lennart
Published: February 2006

The magnetic fields from overhead power lines and other electromagnetic sources were determined at the birth and diagnosis dwellings of all tumor cases reported in the county of Stockholm during the years 1958–73 for individuals 0–18 years of age. The study was limited to 716 cases having a permanent address in the county both at time of birth and diagnosis. An equivalent number of controls was matched to the cases according to church district of birth, age, and sex. Outside each dwelling, the occurrence of visible electrical constructions (6‐200‐kV high‐voltage wires, substations, transformers, electric railroads, and subways) within 150 m of the dwelling was noted. Also, the 50‐Hz magnetic field was measured outside the main entrance of the dwelling. Visible 200‐kv wires were noted at 45 of 2,098 dwellings and were found twice as frequently among cases as among controls (P < .05). The magnetic field measured at the dwelling varied between 0.0004 to 1.9 μT (mean value 0.069 μT). The magnetic field was higher (0.22 μT) at dwellings with visible 200‐kV wires than at those without such wires. Magnetic fields of 0.3 μT or more were measured at 48 dwellings, and were found twice as frequently among cases as among controls (P < .05). The difference was most pronounced for dwellings of nervous system tumors and was less for leukemias.
Low‐intensity magnetic fields alter operant behavior in rats
Authors: Thomas John R. , Schrot John , Liboff Abraham R.
Published: February 2006

The present study demonstrates that operant behavior is affected by a combination of a 60‐Hz magnetic field and a magnetostatic field 2.6 × 10−5T (about half the geomagnetic field). Rats exposed to this combination for 30 min consistently exhibited changes in the rate and pattern of responding during the differential reinforcement of low rate (DRL) component of a multiple fixed ratio (FR) DRL reinforcement schedule. By contrast, there were no measurable changes following exposure to the static field alone or to the oscillating field alone, even with a 10‐fold increase in intensity (5 × 10−5 to 5 × 10−4 Trms). A cyclotron resonance mechanism has been suggested as a possible explanation for the observation that weak static magnetic fields modify the response of in vitro brain tissue to low‐frequency magnetic fields. The choice of static field intensity Bo and frequency v in the present study follows from the cyclotron resonance condition v = (1/2π)(q/m)Bo, for singly charged lithium, an element in extensive use in the clinical treatment of affective disorders in humans. The present research is consistent with a cellular cyclotron resonance mechanism and tends to imply a functional dependence of behavior on the geomagnetic field.
Space charge drift from a +/− 400‐kV direct current transmission line
Authors: Hendrickson Riley C.
Published: February 2006

The Minnesota Environmental Quality Board completed a 3‐year study of the space charge plume outside the right of way of a bipolar ( +/− 400 kV) direct current transmission line in rural west central Minnesota. The purpose of the study was to determine the levels of DC potential gradient and small air ions in the downwind plume to which humans and animals may be exposed. Potential gradient measurements show that a space charge plume is detectable downwind at least 1600 m from the transmission line. Plume relaxation rates indicate that under certain conditions one could detect the plume at twice that distance or more. Net charge in the plume assumes the polarity of the downwind energized transmission line conductor. The bipolar DC line thus electrically bisects the land through which it passes; on one side of the line there is a net positive space charge, on the other side a net negative space charge. Electric charge in the plume resides on aerosols and small air ions. Polar conductivity data substantiate the fact that small air ions of one polarity in the plume are elevated while those of opposite polarity are suppressed compared to background concentrations found in the rural environment. The resulting charge imbalance persists downwind at least 1600 m, though the median small air ion concentrations of plume polarity have adjusted to within the background range by that time with perpendicular wind speed components between 1 and 6 m/sec.
Reproduction of Japanese quail after microwave irradiation (2.45 GHz CW) during embryogeny
Authors: Gildersleeve R. P. , Galvin M. J. , McRee D. I. , Thaxton J. P. , Parkhurst C. R.
Published: February 2006

Japanese quail (Coturnix coturnix japonica) embryos were irradiated continuously in ovo with 2.45‐GHz continuous wave radiation during the first 12 days of embryogenesis at an incident power of 5 mW/cm2 and a specific absorption rate of 4.03 mW/g. The internal temperature of irradiated and nonirradiated (sham) eggs was 37.5 ± 0.3 °C, which is the optimum temperature for incubating quail eggs. At 35 days after hatching irradiated and sham‐irradiated males were paired with irradiated or sham‐irradiated females and daily records of reproductive performance were collected through 224 days of age. Progeny were hatched from each of the male‐female pairs, and progeny reproductive performance was measured from 35 through 168 days of age. Hatchability was not affected by irradiation during embryogeny. Mortality after hatching, egg production, egg weight, fertility, hatchability of eggs produced, and reproductive performance of the progeny were not affected by irradiation during embryogeny. These observations indicate that irradiation of quail embryos with low‐level microwave radiation does not affect the reproductive capacity of the hatchlings or of progeny produced from quail irradiated during incubation.
Effects of 60‐Hz electric fields on cellular elongation and radial expansion growth in cucurbit roots
Authors: Brayman Andrew A. , Miller Morton W. , Cox Christopher
Published: February 2006

Serial longitudinal and transverse sections were prepared from roots of Cucumis sativus and Cucurbita maxima that had been exposed/sham‐exposed to 60‐Hz electric fields for 0–2 days. Field exposures were selected to produce a 10–20% or a 70–80% growth inhibition in whole roots of both species. Cortical cell length and diameter were measured using a microscope and eyepiece micrometer; measurements were conducted “blind”. In both species, inhibition of cellular elongation was associated with exposure to electric fields (EF). Cellular radial expansion was apparently unaffected by exposure to electric fields. The diameters of radially unexpanded or fully expanded C. sativus cortical cells were about 25–30% smaller than those of comparable cells in C. maxima roots. Previous studies of the relationship between rates of root growth and applied EF strength showed that the response thresholds of C. sativus and C. maxima differed by a similar relative amount. These results are consistent with the postulate that EF‐induced effects in roots are elicited by induced transmembrane potentials.
Effect of relative humidity on the movement of rat vibrissae in a 60‐Hz electric field
Authors: Weigel R. J. , Lundstrom D. L.
Published: February 2006

The snouts of rats were placed in a 60‐Hz electric field at an unperturbed field strength of 50 kV/m. A count of the number of vibrissae that moved in the field was made on a series of rats over a number of days where the laboratory humidity varied from 25% to 48%. The number observed to vibrate fell from nine to zero or one at relative humidities between 25% and 39%, respectively.
Effects of low‐amplitude pulsed magnetic fields on cellular ion transport
Authors: Farndale R. W. , Maroudas A. , Marsland T. P.
Published: February 2006

Pulsed magnetic fields (PMFs) are widely used to treat difficult fractures of bone and other disorders of connective tissue. It is not clear how they interact with tissue metabolism, although it has been proposed that induced currents or electric fields impinging on cell membranes may modify their ion transport function. This hypothesis was tested by treating in vitro models for ion transport processes with short‐term exposure to PMFs. No change occurred in active transport of potassium or calcium in human red cells or in calcium transport through an epithelial membrane. We considered less direct action on red cell membranes, that their permeability might be modified after PMF treatment, and also that PMFs might alter the extracellular ionic activity within connective tissue by interacting with its Donnan potential. Each of these studies proved negative, and we conclude that the PMF waveforms used here do not exert a general short‐term effect on cellular ion transport.
Temperature‐specific inhibition of human red cell Na+/K+ ATPase by 2,450‐MHz microwave radiation
Authors: Allis John W. , Sinha‐Robinson Barbara L.
Published: February 2006

The ATPase activity in human red blood cell membranes was investigated in vitro as a function of temperature and exposure to 2,450‐MHz continuous wave microwave radiation to confirm and extend a report of Na+ transport inhibition under certain conditions of temperature and exposure. Assays were conducted spectrophotometrically during microwave exposure with a custom‐made spectrophotometer‐waveguide apparatus. Temperature profiles of total ATPase and Ca+2 ATPase (ouabain‐inhibited) activity between 17 and 31 °C were graphed as an Arrhenius plot. Each data set was fitted to two straight lines which intersect between 23 and 24 °C. The difference between the total and Ca+2 ATPase activities, which represented the Na+/K+ ATPase activity, was also plotted and treated similarly to yield an intersection near 25 °C. Exposure of membrane suspensions to electromagnetic radiation, at a dose rate of 6 W/kg and at five temperatures between 23 and 27 °C, resulted in an activity change only for the Na+/K+ ATPase at 25 °C. The activity decreased by approximately 35% compared to sham‐irradiated samples. A possible explanation for the unusual temperature/microwave interaction is proposed.
Calcium cyclotron resonance and diatom mobility
Authors: Smith Stephen D. , McLeod Bruce R. , Liboff Abraham R. , Cooksey Keith
Published: February 2006

The hypothesis that movement of biological ions may be predicted by cyclotron resonance theory applied to cell membranes is tested in these experiments. Diatoms (Amphora coffeaeformis) were chosen as the biosystem since they move or don't move, depending on how much calcium is transported across the membrane. The experiments demonstrate that a particular ion (calcium) is apparently moved across the cell membrane in response to the DC and AC values of magnetic flux densities (B) and the frequency derived from the cyclotron resonance theory. A clear resonance is shown and a rather sharp frequency response curve is demonstrated. The experiments also show a dose response as the AC value of the flux density is varied, and that odd harmonics of the basic cyclotron frequency are also effective.
Detection of 60‐Hertz vertical electric fields by rats
Authors: Sagan Philip M. , Stell Mark E. , Bryan Guy K. , Adey W. Ross
Published: February 2006

Rats were trained to press levers to indicate the presence or absence of 60‐Hz vertical electric fields at intensities from 0 to 27 kV/m (rms). The probability of detecting the field increased as the strength of the field increased. The shape of the detection curve (psychometric function) for most subjects (Ss) was similar whether the discriminative stimulus was the electric field or a tone. Two protocols were used to estimate the minimum field intensity necessary to detect the field (Reiz Limen, RL). The RL was estimated to be 13.3 kV/m (rms) when using one protocol (the staircase method) and 7.9 kV/m (rms) when using another protocol (the method of constant stimuli).
Characteristics of transverse electric and magnetic field transmission cells at extremely low frequencies
Authors: Wood A. W. , Joines W. T. , Blackman C. F.
Published: February 2006

Transverse electric and magnetic field (TEM) cells are often designed to subject samples to electromagnetic radiation of intrinsic impedance (E/H) that is the same as in free space, 377 ω. Earlier work has shown this value to be correct for the RF region above about 2 kHz. In this study, measurements of magnetic fields in the extremely low frequency regions and at DC indicate the E/H ratio to be around 300 ω for frequencies less than 2 kHz in cells of a particular design. This lower value indicates that care should be taken in estimating AC magnetic field intensities from electric field measurements in TEM cells at frequencies below 2 kHz.
Kinetics of channelized membrane ions in magnetic fields
Authors: Liboff Abraham R. , McLeod B. R.
Published: February 2006

The cyclotron resonance model for channel ion transport in weak magnetic fields is extended to include damping losses. The conductivity tensor is obtained for different electric field configurations, including the circuital field EΦ normal to the channel axis. The conductivity behavior close to the cyclotron resonance frequency ωc is compared to existing Ca2+ ‐efflux data in the literature. A collision time of .023 s results from this comparison under the assumption that K+ ions are transiting in a 0.35 G field. We estimate a mean kinetic energy of 3.5 eV for this ion at resonance. This model leads to discrete modes of vibration (eigenfrequencies) in the ion‐lattice interaction, such that ωn = nωc. The presence of such harmonics is compatible with recent results by Blackman et al. [1985b] and McLeod et al. [1986] with the interesting exception that even modes do not appear in their observations, whereas the present model has no restriction on n. This harmonic formalism is also consistent with another reported phenomenon, that of quantized multiple conductances in single patch‐clamped channels.
Influence of 60‐hertz magnetic fields on leukemia
Authors: Thomson Roderick A. E. , Michaelson Sol M. , Nguyen Quang A.
Published: February 2006

Female DBA/2 mice at 8 weeks of age were implanted with P388 leukemia cells in groups of ten mice and exposed to a 60‐Hz 1.4‐μT, 200‐μT, or 500‐μT magnetic field 2‐3 hours after the implant for 6 hours daily, 5 days/week until all the exposed P388‐treated and nontreated mice died. Parallel exposed groups of non‐P388‐treated mice and P388‐treated mice exposed at 0 μT were included for study. No statistically significant differences (P > .05) in survival, spleen weight, or body weight resulted between P388‐treated or nontreated mice from exposure to the magnetic field. No effect on the incidence or progression of P388 leukemia was apparent.
Modulation of tendon fibroplasia by exogenous electric currents
Authors: Cleary Stephen F. , Liu Li‐Ming , Graham Ronald , Diegelmann Robert F.
Published: February 2006

A chicken tendon explant model system has been developed to investigate the effects of extremely‐low‐frequency (ELF), low‐amplitude, unipolar, square wave pulsed electric fields on fibroplasia in vitro. An electric field parameter set consisting of 1‐Hz, 1‐ms duration pulses, with a time‐averaged current density of 7 mA/m2 (peak current density 7 A/m2) induced maximal (32%) increase in fibroblast proliferation in tendon explants exposed for 4 days. Exposure to the same field at an average current density of 1.8 mA/ m2 had no effect on fibroblast proliferation, whereas exposure to current densities on > 10 mA/m2 inhibited proliferation and relative collagen synthesis, without affecting noncollagen protein synthesis. Fibroplasia was significantly increased in explants oriented parallel to applied electric fields having current densities of 3.5 or 7 mA/m2, but there was no detectable effect on explants oriented perpendicular to the same electric field. Fibroblast proliferation and relative collagen synthesis were inversely proportional to donor age for chickens in the 3‐ to 16‐week age group used in this study. For these dependent variables (proliferation and relative collagen synthesis), there was no interaction between donor age and ELF electric field exposure.
Learning ability of young rats is unaffected by repeated exposure to a static electromagnetic field in early life
Authors: Hong Chang‐Zern , Huestis Peter , Thompson Robert , Yu Jen
Published: February 2006

Infant albino rats were exposed to a static electromagnetic field of 0.0 Tesla (control) or 0.5 Tesla (experimental) for 14 postnatal days. Following a 1‐month rest period, the experimental (13 males and 10 females) and control (11 males and 14 females) rats were trained on four successive reversals of a position habit in a single‐unit enclosed T‐maze that was adapted for the use of escape‐avoidance of mild foot shock as a motive. There was no significant difference in learning ability between the experimental and control groups in terms of total (initial combined with repetitive) errors committed over the four reversal problems. While the females tended to make more errors than the males, this difference was likewise insignificant.
Exposure scheme separates effects of electric shock and electric field for honey bees, Apis mellifera L.
Authors: Bindokas Vytautas P. , Gauger James R. , Greenberg Bernard
Published: February 2006

Mechanisms to explain disturbance of honey bee colonies under a 765‐kV, 60‐Hz transmission line [electric (E) field = 7 kV/m] fall into two categories: direct bee perception of enhanced in‐hive E fields, and perception of shock from induced currents. The same adverse biological effects previously observed in honey bee colonies exposed under a 765‐kV transmission line can be reproduced by exposing worker bees to shock or E field within elongated hive entranceways (=tunnels). Exposure to intense E field caused disturbance only if bees were in contact with a conductive substrate. E‐field and shock exposure can be separated and precisely defined within tunnels, eliminating dosimetric vagaries that occur when entire hives are exposed to E field.
Mechanism of biological effects observed in honey bees (apis mellifera, L.) hived under extra‐high‐voltage transmission lines: Implications derived from bee exposure to simulated intense electric fields and shocks
Authors: Bindokas Vytautas P. , Gauger James R. , Greenberg Bernard
Published: February 2006

This work explores mechanisms for disturbance of honey bee colonies under a 765 kV, 60‐Hz transmission line [electric (E) field = 7 kV/m] observed in previous studies. Proposed mechanisms fell into two categories: direct bee perception of enhanced in‐hive E fields and perception of shock from induced currents. The adverse biological effects could be reproduced in simulations where only the worker bees were exposed to shock or to E field in elongated hive entranceways (=tunnels). We now report the results of full‐scale experiments using the tunnel exposure scheme, which assesses the contribution of shock and intense E field to colony disturbance.
Exposure of worker bees (1,400 h) to 60‐Hz E fields including 100 kV/m under moisture‐free conditions within a nonconductive tunnel causes no deleterious affect on colony behavior. Exposure of bees in conductive (e.g., wet) tunnels produces bee disturbance, increased mortality, abnormal propolization, and possible impairment of colony growth. We propose that this substrate dependence of bee disturbance is the result of perception of shock from coupled body currents and enhanced current densities postulated to exist in the legs and thorax of bees on conductors.
Similarly, disturbance occurs when bees are exposed to step‐potential‐induced currents. At 275–350 nA single bees are disturbed; at 600 nA bees begin abnormal propolization behavior; and stinging occurs at 900 nA.
We conclude that biological effects seen in bee colonies under a transmission line are primarily the result of electric shock from induced hive currents. This evaluation is based on the limited effects of E‐field exposure in tunnels, the observed disturbance thresholds caused by shocks in tunnels, and the ability of hives exposed under a transmission line to source currents 100–1,000 times the shock thresholds.
Laboratory investigations of the electrical characteristics of honey bees and their exposure to intense electric fields
Authors: Bindokas Vytautas P. , Gauger James R. , Greenberg Bernard
Published: February 2006

Bees exposed to 60‐Hz electric (E) fields > 150 kV/m show field‐induced vibrations of wings, antennae, and body hairs. They also show altered behavior if exposed while in contact with a conductive substrate. Measurements indicate that approximately 240 nA is coupled to a bee standing on a conductive substrate in a 100‐kV/m E field. In lab experiments, bee disturbance and sting result from exposure to E field >200 kV/m (bee current >480 nA) and reduced voluntary movements at >300 kV/m (>720 nA bee current) only if the bee is on a conductive substrate. It is hypothesized that in the latter situation coupled bee current drains through the lower thorax and legs to the conductive substrate, and that the resulting enhanced current density in these regions is the cause of observed responses. The observation that bees exposed to intense E fields on an insulator show vibration of body parts but no behavioral response suggests that vibration contributes little to the disturbance of bees in intense E fields.

Lab measurements of bee impedance from front‐to‐rear leg pairs were made on wet and dry conductors. Measurements validate the selection of 1 MΩ as a middle value for bee impedance used in the design of devices used to generate step‐potential‐induced currents in bees.
Use of wiring configuration and wiring codes for estimating externally generated electric and magnetic fields
Authors: Barnes Frank , Wachtel Howard , Savitz David , Fuller Jackson
Published: February 2006

The relative locations and characteristics of the distribution lines feeding 434 residences in the Denver metropolitan area were recorded and classified according to the Wertheimer‐Leeper code (WL code) as a part of an epidemiological study of the incidence of childhood cancer. The WL code was found to place the mean values of the fields in rank order. However, the standard deviations were approximately the same size as the means. Theoretical calculations indicate that a significant fraction of the low‐power magnetic fields can be generated by the distribution lines, especially in the cases where the distribution lines are within 50 feet of the residence. Thus, the wiring code was shown to be a useful method for making a first‐order approximation to predict long‐term, low‐level magnetic fields in residences.
Relationship between local temperature and heat transfer through the hand and wrist
Authors: Sienkiewicz Z. J. , O'Hagan J. B. , Muirhead C. R. , Pearson A. J.
Published: February 2006

The heat uptake that resulted from immersing the hand and wrist into a water‐filled calorimeter maintained at temperatures between 37–40 °C was measured under standard conditions in a group of eight subjects of either sex. The rate of heat transfer (W) increased exponentially with temperature and was a function of hand or body size and age, but not sex. The heat transfer rate normalized to hand mass (W.kg−1) was determined by temperature and age: best‐fit mean values (and 95% confidence limits of the population) were 6.0 W.kg−1(3.2–11.2 W.kg−1) at an immersion temperature of 37 °C and 25.4 W.kg−1(13.7–47.0 W.kg−1) at 40 °C. The application of these results to limits on specific energy absorption rate induced in the hands and wrists by radiofrequency dielectric heat sealer welders is discussed.
Outdoor measurement of SAR in a full‐sized human model exposed to 29.9 MHz in the near field
Authors: Olsen Richard G. , Griner Toby A.
Published: February 2006

Localized and averaged specific absorption rates (SARs) were obtained in a full‐size muscle‐equivalent human model exposed to near‐field 29.9 MHz irradiation at an outdoor facility. The model was positioned erect on a metallic groundplane 1.22 m (4 ft) from the base of a 10.8‐m (35 ft) whip antenna with an input power of 1.0 kW. For whole‐body SAR, a mean value of 0.83 W/kg was determined using two gradient‐layer calorimeters in a twin‐well configuration. The localized SARs at 12 body locations were measured using nonperturbing temperature probes and were highest in the ankle region. We conclude that averaged SAR measurements in a full‐size phantom are feasible using a twin‐calorimeter approach; measurements in the field are practical when human‐size (183 × 61 × 46 cm) calorimeters are used.