bluuebunny/crossref_metadata_2025_split huggingface dataset:
Rhesus monkey behavior during exposure to high‐peak‐power 5.62‐GHz microwave pulses
Authors: D'andrea John A. , Thomas Alfred , Hatcher Donald J. 
Published: February 2006

AbstractLimits on the exposure to high‐peak‐power, short‐duration microwave pulses have only recently been adopted. Additional data, however, are needed to understand the effects that may be produced by exposure to high‐peak‐power pulsed microwaves. Four male rhesus monkeys (Macaca mulatta) were trained on an operant task for food pellet reward to investigate the behavioral effects of very high‐peak‐power 5.62 GHz microwaves. The operant task required monkeys to pull one plastic lever on a variable interval schedule (VI‐25 s) and then respond to color signals and pull a second lever to obtain food. The monkeys were conditioned to perform a color discrimination task using one of three colors displayed by a fiber‐optic cable. A red signal was the discriminative stimulus for responding on the first lever. A response on the second lever when a green signal was presented (1 s duration) delivered a food pellet. If a response on the second lever was made in the presence of a white signal, a 30‐s timeout occurred. While performing the behavioral task, the monkeys were exposed to microwave pulses produced by either a military radar (FPS‐26A) operating at 5.62 GHz or the same radar coupled to a Stanford linear energy doubler (SLED) pulse‐forming device (ITT‐2972) that enhanced peak power by a factor of nine by adding a high power pulse to the radar pulse. The effects of both types of pulses were compared to sham exposure. Peak field power densities tested were 518, 1270, and 2520 W/cm2 for SLED pulses and 56, 128, and 277 W/cm2 for the radar pulses. The microwave pulses (radar or SLED) were delivered at 100 pps (2.8 μs radar pulse duration, ≈ 50 ns SLED pulse duration) for 20 min and produced averaged whole‐body SARs of 2,4, or 6 W/kg. Compared to sham exposures, significant alterations of lever responding, reaction time, and earned food pellets occurred during microwave exposure at 4 and 6 W/kg but not 2 W/kg. There were no differences between radar or SLED pulses in producing behavioral effects. ©1994 Wiley‐Liss, Inc.This is a US Government work and, as such, is in the public domain in the United States of America.
Alteration of life span of mice chronically exposed to 2.45 GHz CW microwaves
Authors: Liddle Charles G. , Putnam Julia P. , Huey Ora P. 
Published: February 2006

AbstractFemale CD 1 mice were exposed from the thirty‐fifth day of age for the remainder of their lives to 2.45 GHz, CW‐microwave radiation at a power density of 3 or 10 m W/cm2 (SAR = 2.0 or 6.8 W/kg). Exposures took place 1 h/day, 5 day/week in an anechoic chamber at an ambient temperature of 22 °C and a relative humidity of 50%. There were 25 animals in each exposure group, and an equal number of controls were concurrently sham exposed. The average life span of animals exposed at 10 mW/cm2 was significantly shorter than that of sham‐exposed controls (572 days vs. 706 days; P = .049; truncation >20%). In contrast, the average lifespan of the animals exposed at 3 mW/cm2 was slightly, but not significantly, longer (738 days) than that of controls (706 days). © 1994 Wiley‐Liss, Inc.This article is a US Government work and, as such, is in the public domain in the United States of America.
Clarification and application of an ion parametric resonance model for magnetic field interactions with biological systems
Authors: Blanchard J. P. , Blackman C. F. 
Published: February 2006

AbstractTheoretical models proposed to date have been unable to clearly predict biological results from exposure to low‐intensity electric and magnetic fields (EMF). Recently a predictive ionic resonance model was proposed by Lednev, based on an earlier atomic spectroscopy theory described by Podgoretskii and Podgoretskii and Khrustalev. The ion parametric resonance (IPR) model developed in this paper corrects mathematical errors in the earlier Lednev model and extends that model to give explicit predictions of biological responses to parallel AC and DC magnetic fields caused by field‐induced changes in combinations of ions within the biological system. Distinct response forms predicted by the IPR model depend explicitly on the experimentally controlled variables: magnetic flux densities of the AC and DC magnetic fields (Bacand Bdc, respectively); AC frequency (fac); and, implicitly, charge to mass ratio of target ions. After clarifying the IPR model and extending it to combinations of different resonant ions, this paper proposes a basic set of experiments to test the IPR model directly which do not rely on the choice of a particular specimen or endpoint. While the fundamental bases of the model are supported by a variety of other studies, the IPR model is necessarily heuristic when applied to biological systems, because it is based on the premise that the magnitude and form of magnetic field interactions with unhydrated resonant ions in critical biological structures alter ion‐associated biological activities that may in turn be correlated with observable effects in living systems. © 1994 Wiley‐Liss, Inc.
Empirical test of an ion parametric resonance model for magnetic field interactions with PC‐12 cells
Authors: Blackman C. F. , Blanchard J. P. , Benane S. G. , House D. E. 
Published: February 2006

AbstractA companion paper describes a predictive ion parametric resonance (IPR) model of magnetic field interactions with biological systems based on a selective relation between the ratio of the flux density of the static magnetic field to the AC magnetic field and the charge‐to‐mass ratio of ions of biological relevance. Previous studies demonstrated that nerve growth factor (NGF)‐stimulated neurite outgrowth (NO) in PC‐12 cells can be inhibited by exposure to magnetic fields as a function of either magnetic field flux density or AC magnetic field frequency. The present work examines whether the PC‐12 cell response to magnetic fields is consistent with the quasiperiodic, resonance‐based predictions of the IPR model. We tested changes in each of the experimentally controllable variables [flux densities of the parallel components of the AC magnetic field (Bac) and the static magnetic field (Bdc) and the frequency of the AC magnetic field] over a range of exposure conditions sufficient to determine whether the IPR model is applicable. A multiple‐coil exposure system independently controlled each of these critical quantities. The perpendicular static magnetic field was controlled to less than 2 mG for all tests. The first set of tests examined the NO response in cells exposed to 45 Hz Bacfrom 77 to 468 mG(rms) at a Bdcof 366 mG. Next, we examined an off‐resonance condition using 20 mG Bdcwith a 45 Hz AC field across a range of Bacbetween 7.9 and 21 mG(rms). Finally, we changed the AC frequency to 25 Hz, with a corresponding change in Bdcto 203 mG (to tune for the same set of ions as in the first test) and a Bacrange from 78 to 181 mG(rms). In all cases the observed responses were consistent with predictions of the IPR model. These experimental results are the first to support in detail the validity of the fundamental relationships embodied in the IPR model. © 1994 Wiley‐Liss, Inc.
Residential magnetic fields, wire codes, and pregnancy outcome
Authors: Savitz David A. , Ananth Cande V. 
Published: February 2006

AbstractThe relationship of measured residential magnetic fields and wire codes to pregnancy outcome was examined in data collected for a study of childhood cancer in Denver. Pregnancies in homes with measured fields above 0.2 μT or high wire codes were not more likely to end in miscarriage, low birth weight, or preterm delivery. Lack of data on potential confounders and small numbers of cases limit the study's conclusions. © 1994 Wiley‐Liss, Inc.
Chromosomal aberrations in human amniotic cells after intermittent exposure to fifty hertz magnetic fields
Authors: Nordenson Ingrid , Mild Kjell Hansson , Andersson Gunilla , Sandström Monica 
Published: February 2006

AbstractOur recent studies have shown a significant increase in the frequency of chromosomal aberrations in human amniotic cells after exposure to a sinusoidal 50 Hz, 30 μT (rms) magnetic field. To evaluate further interactions between chromosomes and electromagnetic fields, we have analyzed the effects of intermittent exposure. Amniotic cells were exposed for 72 h to a 50 Hz, 30 μT (rms) magnetic field in a 15 s on and 15 s off fashion. Eight experiments with cells from different fetuses were performed. The results show a 4% mean frequency of aberrations among exposed cells compared to 2% in sham‐exposed cells. The difference is statistically significant, withP< 0.05 both excluding and including gaps. In another series of eight experiments, the cells were exposed in the same way but with the field on for 2 s and off for 20 s. Also in these experiments a similar increase in the frequency of chromosomal aberrations was seen, but only when the analysis included gaps. Continuous exposure for 72 h to 300 μT, 50 Hz, did not increase the frequency of chromosomal aberrations. The background electromagnetic fields at different locations within the two incubators used was carefully checked and was nowhere found to exceed 120 nT. Likewise, the background level of chromosomal aberrations in cells cultured at different locations in the incubators showed no significant interculture differences. © 1994 Wiley‐Liss, Inc.
Effect of microwave radiation on the permeability of carbonic anhydrase loaded unilamellar liposomes
Authors: Orlando Alfonsina Ramundo , Mossa Giuseppe , D'lnzeo Guglielmo 
Published: February 2006

AbstractThe influence of 2.45 GHz microwave exposure (6 mW/g) on the diffusion processes in enzyme‐loaded unilamellar liposomes as bioreactors was studied. The enzyme carbonic anhydrase (CA) was entrapped into cationic unilamellar vesicles. Previous kinetic experiments showed a very low self‐diffusion rate of the substrate p‐nitrophenyl acetate (PNPA) across intact liposome bilayer. A twofold increase in the diffusion rate of PNPA through the lipid bilayer was observed after 120 min of microwave radiation compared to temperature control samples. The microwave effect was time dependent. The enzyme activity, as a function of increased diffusion of PNPA, rises over 120 min from 22.3% to 80%. The increase in stearylamine concentration reduces the enzyme activity from 80% to 65% at 120 min. No enzyme leakage was observed. © 1994 Wiley‐Liss, Inc.
Synthesis of diazoluminomelanin (DALM) in HL‐60 cells for possible use as a cellular‐level microwave dosimeter
Authors: Bruno John G. , Kiel Johnathan L. 
Published: February 2006

AbstractChemical and bacterial synthesis of a thermochemiluminescent polymer known as diazoluminomelanin (DALM) has been previously reported. This paper focuses on the intracellular synthesis of aminomelanin (AM) in mammalian cell lines and subsequent DALM synthesis from this core molecule. B16 melanoma cells, HL‐60 myeloid leukemia cells, and RAW 264.7 macrophages show AM and DALM production. Macroscopic image analysis of HL‐60 cell lysates containing DALM using the Quantitative Luminescence Imaging System (QLIS) showed increased chemiluminescence (CL) with increased microwave power input and increased temperature. This work represents a first step toward the goal of microscopic radiofrequency dosimetry of individual DALM‐loaded cells using image analysis. © 1994 Wiley‐Liss, Inc.
Frequency‐dependent alterations in enolase activity inEscherichia colicaused by exposure to electric and magnetic fields
Authors: Dutta S. K. , Verma M. , Blackman C. F. 
Published: February 2006

AbstractSome neurochemical effects of low‐intensity electric and magnetic fields have been shown to be nonlinear functions of exposure parameters. These effects occurred within narrow ranges of frequency and intensity. Previous studies on membrane‐associated endpoints in cell culture preparations demonstrated changes in calcium efflux and in acetylcholinesterase activity following exposure to radiofrequency radiation, amplitude modulated (AM) at 16 and at 60 Hz, at a specific absorption rate of 0.05 W/kg. In this study, these modulation frequencies were tested for their influence on the activity of a cytoplasmic enzyme, enolase, which is being tested clinically for detection of neoplasia.Escherichia colicultures containing a plasmid with a mammalian gene for enolase were exposed for 30 min, and cell extracts were assayed for enolase activity by measuring absorbance at 240 nm. The enolase activity in exposed cultures was compared to the activity in paired control cultures. Exposure to 147 MHz carrier waves at 0.05 W/kg, AM at 16 Hz showed enolase activity enhanced by 62%, and AM at 60 Hz showed enolase activity reduced by 28%. Similarly, exposure to 16 Hz fields alone, at 21.2 V/mrms(electric) and 97 nTrms(magnetic), showed enhancement in enolase activity by 59%, whereas exposure to 60 Hz fields alone, at 14.1 V/mrms(electric) and 65 nTrms(magnetic), showed reduction in activity by 24%. Sham exposures as well as exposure to continuous‐wave 147 MHz radiation at 0.05 W/kg showed no change in enolase activity. Although the underlying basis for these field effects in the cytoplasmic compartment has not been established, differential sensitivities to 16 Hz and to 60 Hz signals provide a clear focus for additional research to determine the responsible mechanism. © 1994 Wiley‐Liss, Inc.
Application of the radical pair mechanism to free radicals in organized systems: Can the effects of 60 Hz be predicted from studies under static fields?
Authors: Scaiano J. C. , Mohtat N. , Cozens F. L. , McLean J. , Thansandote A. 
Published: February 2006

AbstractThe influence of 60‐Hz magnetic fields on free radical reactions can be quantitatively predicted from the knowledge of the effect of static fields on free radical behavior. Studies of radical reactions in micellar systems show that the behavior under a 60‐Hz field is identical to that under a static field at any given point in time. © 1994 Wiley‐Liss, Inc.
Effects of extremely‐law‐frequency electromagnetic fields on ion transport in several mammalian cells
Authors: García‐Sancho Javier , Montero Mayte , Alvarez Javier , Fonteriz Rosalba I. , Sanchez Ana 
Published: February 2006

AbstractWe have investigated the effects of sinusoidal electromagnetic fields (EMF) on ion transport (Ca2+, Na+, K+, and H+) in several cell types (red blood cells, thymocytes, Ehrlich ascites tumor cells, and HL60 and U937 human leukemia cells). The effects on the uptake of radioactive tracers as well as on the cytosolic Ca2+ concentration ([Ca2+]i), the intracellular pH (pHi), and the transmembrane potentsial (TMP) were studied. Exposure to EMF at 50 Hz and 100–2000 μT (rms) had no significant effects on any of these parameters. Exposure to EMF of 20–1200 μT (rms) at the estimated cyclotron magnetic resonance frequencies for the respective ions had no significant effects except for a 12–32% increase of the uptake of 42K within a window at 14.5–15.5 Hz and 100–200 μT (rms), which was found in U937 and Ehrlich cells but not in the other cell types. © 1994 Wiley‐Liss, Inc.
Trivial influences: A doubly stochastic poisson process model permits the detection of arbitrarily small electromagnetic signals
Authors: Pickard William F. 
Published: February 2006

AbstractIf a weak, exogenous, extremely low‐frequency (ELF) electric or magnetic field is to produce biological sequelae, then there must exist averaging sufficient to lift some primary effect of that field above the endogenous stochastic variations of the biological system. One way in which a field could accomplish this is by changing the intensity of some stochastic operation that controls an important and not trivially reversible biological transformation. In this paper, this operation is modeled as a doubly stochastic Poisson process. It is then shown, first, that (in theory) even a minuscule exogenous influence might appreciably shift the incidence of a sufficiently rare transformation and, second, that this shift might be observable if a trial were allowed to run long enough over a sufficiently large population of exposed entities. © 1995 Wiley‐Liss, Inc.
Model for external influences on cellular signal transduction pathways including cytosolic calcium oscillations
Authors: Eichwald C. , Kaiser F. 
Published: February 2006

AbstractExperiments on the effects of extremely‐low‐frequency (ELF) electric and magnetic fields on cells of the immune system, T‐lymphocytes in particular, suggest that the external field interacts with the cell at the level of intracellular signal transduction pathways. These are directly connected with changes in the calcium‐signaling processes of the cell. Based on these findings, a theoretical model for receptor‐controlled cytosolic calcium oscillations and for external influences on the signal transduction pathway is presented. We discuss the possibility that the external field acts on the kinetics of the signal transduction between the activated receptors at the cell membrane and the G‐proteins. It is shown that, depending on the specific combination of cell internal biochemical and external physical parameters, entirely different responses of the cell can occur. We compare the effects of a coherent (periodic) modulation and of incoherent perturbations (noise). The model and the calculations are based on the theory of self‐sustained, nonlinear oscillators. It is argued that these systems form an ideal basis for information‐encoding processes in biological systems. © 1995 Wiley‐Liss, Inc.
Microwave ablation of the atrioventricular junction in open‐chest dogs
Authors: Lin James C. , Beckman Karen J. , Hariman Robert J. , Bharati Saroja , Lev Maurice , Wang Yu‐Jin 
Published: February 2006

AbstractThe 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. In protocol 2, only two applications of energy were used, one at low energy and the other at an energy found to be high enough to cause irreversible AV block. Each dog received between one and six applications of microwave energy. The amount of energy delivered per application ranged from 25.6 to 311.4 J. No AV block was seen at 59.4 ± 28.3 J. Reversible AV block was seen with an energy of 120.6 ± 58 J. Irreversible AV block was seen at 188.1 ± 75.9 J. Irreversible AV block could be achieved in each animal. There was no difference in the energy required to cause irreversible AV block between the two protocols. The tissue temperature measured near the tip of the microwave catheter was correlated with both the amount of energy delivered and the extent of AV block caused. Histologic examination demonstrated coagulation necrosis of the conduction system. Microwave energy is a feasible alternative energy source for myocardial ablation. Since tissue damage is due exclusively to heating and the resulting rise in temperature can be measured, microwave energy may have advantages over currently existing energy sources in terms of both titrating delivered energy and monitoring the extent of tissue destruction. © 1995 Wiley‐Liss, Inc.
Imprecise exposure assessment and the sample size requirements of case‐control studies of residential magnetic field exposure and cancer in adults
Authors: Delpizzo Vincent 
Published: February 2006

AbstractA computer program simulating case‐control studies is described. It is used to estimate the minimum sample size required and to assess how this is affected by imprecise exposure assessment. In particular, the consequences of neglecting measurements of nonresidential exposure in case‐control studies of residentially exposed adults are investigated. According to this model, while the consequent loss of power is not as large as was predicted by algebraic methods, it would be unwise to neglect it when planning a study. © 1995 Wiley‐Liss, Inc.
Suspension osteopenia in mice: Whole body electromagnetic field effects
Authors: Simske S. J. , Luttges M. W. 
Published: February 2006

AbstractWhole‐body fields were tested for their efficacy in preventing the osteopenia caused by tail suspension in mice. The fields had fundamental frequencies corresponding to the upper range of predicted endogenous impact‐generated frequencies (0.25–2.0 kHz) in the long bones. Three distinct whole‐body EMFs were applied for 2 weeks on growing mice. Structural, geometric, and material properties of the femora, tibiae, and humeri of suspended mice were altered compared to controls. Comparison of suspended mice and mice subjected to caloric restriction indicates that the changes in caloric intake do not explain either the suspension or the field‐induced effects. In agreement with past studies, rather, unloading appears to cause the suspension effects and to be addressed by the EMFs. The EMF effects on bone properties were apparently frequency dependent, with the lower two fundamental frequencies (260 and 910 Hz) altering, albeit slightly, the suspension‐induced bone effects. The fields are not apparently optimized for frequency, etc., with respect to therapeutic potential; however, suspension provides a model system for further study of the in vivo effects of EMFs. © 1995 Wiley‐Liss, Inc.
Absorbed energy distribution from radiofrequency electromagnetic radiation in a mammalian cell model: Effect of membrane‐bound water
Authors: Liu Li‐Ming , Cleary Stephen F. 
Published: February 2006

AbstractThe spatial distributions of induced 27 or 2450 MHz radiofrequency (RF) electric fields (E‐fields) and specific absorption rates (SARs) in a three‐component spherical cell model (cytoplasm, membrane, extracellular space) were determined by Mie scattering theory. The results were compared to results for the same cell model but with 0.5 nm thick of bound water on the inner (cytoplasmic) and outer (extracellular) membrane surfaces (i.e., five‐component cell model). The results provide insight regarding direct frequency‐dependent RF radiation effects at the cellular level. Induced E‐fields and SARs were calculated for two bound‐water characteristic frequencies (400 or 1000 MHz) and ionic conductivities (1–1000 mS/m). In order to estimate the dependence of the results on bound water within the membrane per se, the model was revised to include bound water within the inner and outer membrane surfaces. The results were as follows: (1) On the x‐axis, the y‐ and z‐components of the induced E‐field were of insignificant magnitude compared to the x‐component for an incident E‐field parallel to the x‐axis; (2) the ratio of transmembrane E‐fields induced by 2450 MHz vs. 27 MHz RF [i.e., Ex (2450 MHz)/Ex (27 MHz)] was 0.1; (3) for the three‐component cell model, the corresponding SAR ratios [SAR (2450 MHz)/SAR (27 MHz)] in the cytoplasm and extracellular space were 1.66 and 5.0, respectively; (4) the SAR ratios [SAR (2450 MHz)/SAR (27 MHz)] for the cytoplasm and extracellular space for the five‐component cell model were 1.66 and 5.0, respectively; (5) the ratio of the E‐fields induced in the cytoplasmic and extracellular layers of bound water in the five‐component cell model [E (2450 MHz)/E (27 MHz)] were 0.62 and 0.63, respectively; (6) the SAR ratios [SAR (2450 MHz)/SAR (27 MHz)] for the cytoplasmic and extracellular bound‐water layers were 66 and 65.3, respectively; and (7) variation of bound‐water characteristic frequency, ionic conductivity, or bound‐water incorporation inside the membrane surfaces, per se, did not significantly affect the E‐field or SAR ratios. These results indicate that frequency‐dependent nonuniformities may occur in the distribution of induced RF E‐fields and SARs at the cellular level. © 1995 Wiley‐Liss, Inc.