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PubMedDate not supplied

Application of intensified (+) Qi Gong energy, (-) electrical field, (S) magnetic field, electrical pulses (1-2 pulses/sec), strong Shiatsu massage or acupuncture on the accurate organ representation areas of the hands to improve circulation and enhance drug uptake in pathological organs: clinical applications with special emphasis on the "Chlamydia-(Lyme)-uric acid syndrome" and "Chlamydia-(cytomegalovirus)-uric acid syndrome".

Various methods of improving circulation and enhancing drug uptake which were used in treating some intractable medical problems caused by infections, and two syndromes based on the co-existence of Chlamydia trachomatis infection (mixed with either Lyme Borrelia burgdorferi or Cytomegalovirus) with increased Uric acid are described. The principal author's previous studies have indicated that there are two opposite types of Qi Gong energy, positive (+) and negative (-). Positive (+) Qi Gong energy has been used clinically to enhance circulation and drug uptake in diseased areas where there is a micro-circulatory disturbance and drug uptake is markedly diminished. (-) Qi Gong energy has completely the opposite effect and therefore has not been used although there may be some as yet undiscovered application. Since the late 1980's the principal author has succeeded in storing (+) Qi Gong energy on a variety of substances including small sheets of paper, and recently has been able to intensify this energy by concentrating it as it passes through a cone-shaped, tapered glass or plastic object placed directly on the (+) Qi Gong energy stored paper. Application of (+) Qi Gong energy stored paper on the cardio-vascular representation area of the medulla oblongata at the occipital area of the skull often improved circulation and enhanced drug uptake. If the drug-uptake enhancement was still not sufficient for the drug to reach therapeutic levels in the diseased organ, direct application of (+) Qi Gong from the practitioner's hand often enhanced the drug uptake more significantly. However, this direct method often results in the practitioner developing intestinal micro-hemorrhage within 24 hours which may or may not be noticed as mild intestinal discomfort with soft, slightly tarry stool. For intensifying (+) Qi Gong energy one of the most efficient shapes is a cone with increased intensification occurring at an optimal height. However when the total mass and the total distance from base to peak is increased beyond an optimal limit, the power decreases. Clinical application of Intensified (+) Qi Gong stored energy was evaluated in this preliminary study which indicated that intensified (+) Qi Gong energy application on the heart representation area of the middle finger on the hands markedly improved circulation in the corresponding organ, and increased drug uptake and acetylcholine even more effectively than some of the previously used drug enhancement methods (Shiatsu massage of the organ representation areas and/or application of (+) Qi Gong energy stored paper to the occipital area above the cardiovascular representation area of the medulla oblongata).(ABSTRACT TRUNCATED AT 400 WORDS)

Acupuncture Therapy↗
PubMed1998

A crossover clinical investigation of the safety and efficacy of a new oscillating/rotating electric toothbrush and a high frequency electric toothbrush.

PURPOSE: To compare the efficacy on plaque, gingivitis and calculus of an oscillating/rotating power toothbrush (Braun Oral-B Ultra Plaque Remover-D9) and a high frequency toothbrush (sonicare). MATERIALS AND METHODS: A 6-week, randomized crossover study was carried out. A total of 62 healthy adult subjects completed the study and were assessed for plaque control, gingival condition and calculus control. At the end of the study, subjects completed a questionnaire which assessed their preferences for the two devices. RESULTS: Both toothbrushes were found to be safe and effective, but a significantly lower gingival index (P = 0.002) and a lower calculus index (P = 0.022) was found in the D9 group. Assessment of patient preferences revealed that a significant majority of subjects in the study (65%) preferred the D9 to the high frequency toothbrush (27%). It is concluded that the D9 may offer greater potential for the maintenance of good gingival condition than the high frequency toothbrush, and that the greater preference for the D9 may be important with respect to long-term compliance. The implications of these findings are discussed.

Adult↗
PubMed1985

Torpedo electromotor system development: developmentally regulated neuronotrophic activities of electric organ tissue.

Explant cultures of electric lobe from 45-60 mm stage Torpedo embryos and both ganglionic and dissociated cell cultures prepared from 8-day chick ciliary ganglia have been used to determine whether the electric organs of Torpedo marmorata contain developmentally regulated neuronotrophic activity. Electric lobe explants were evaluated by measuring their neurone density, choline acetyltransferase (CAT0, and low salt, Triton X-100-soluble protein contents. Addition of soluble extracts prepared from the electric organs of late stage embryos (85-105 mm) to standard medium results in the maintenance of nearly theoretical neurone densities in electric lobe explants during a 7-day culture period. Soluble electric organ extracts from early embryonic stages (42-59 mm) do not increase neurone density relative to control cultures but cause an elevation in the CAT content of the explants over control values. On the basis of this analysis it is concluded (1) that late embryonic stage and adult electric organs contain neuronotrophic activity that allows electromotor neurones to survive in vitro and (2) that activity increases rapidly in the electric organs between the 59 nd 72 mm stages of development at a time when rapid increases in postsynaptic membrane markers in the electric organs occur and when peripheral synaptogenesis begins. The activity of late stage embryonic electric organs is heat stable and lost on dialysis. Using ciliary ganglion explants and evaluating both the initial fibre outgrowth and the CAT content after 4 days in vitro, trophic activity is found to be maximal at early embryonic stages (45-55 mm) and to decline thereafter. It is shown that the decline in activity is not due to an increase in toxicity. Using established dissociated ganglionic cell survival assays the specific activity of neuronotrophic factors allowing survival is constant between the 45 and 73 mm stages in the electric organs and then rapidly declines, but activity per electric organ increases rapidly between the 45 and 73 mm stages and then remains at a constant level. The use of poly-dl-ornithine substrates coated with heart-conditioned medium for the cell survival assay results in up to tenfold increase in the trophic titre of the electric organ extracts. The neuronotrophic activity supporting survival of ciliary motorneurones present in embryonic electric organs is heat labile and retained on dialysis. It is concluded that developing electric organs contain at least two neuronotrophic factors that have different properties and are differently regulated. Both factors may contribute during development to bringing naturally occurring electromotor neurone cell death to an end.

Animals↗
PubMed1996

Neuronal responses in cat primary auditory cortex to electrical cochlear stimulation. II. Repetition rate coding.

1. Responses of neurons in primary auditory cortex (AI) of the barbiturate-anesthetized adult cat were studied using cochlear stimulation with electrical and acoustic stimuli. Neuronal responses to acoustic stimulation with brief biphasic clicks of the ear ipsilateral to the studied cortical hemisphere were compared with those evoked by electrical stimulation of the contralateral cochlea with brief biphasic electrical pulses delivered via a feline cochlear prosthesis. The contralateral ear was deafened immediately before implantation of the cochlear prosthesis. The feline cochlear prosthesis consisted of four bipolar electrode pairs and was placed in the scala tympani. Two bipolar electrode conditions were used for stimulation: one near radial pair with electrode spacing of 0.25-0.5 mm, and one longitudinal pair with electrode spacing of approximately 6 mm. 2. The firing rates obtained from single- and multiple-neuron recordings were measured as a function of stimulus repetition rate of electrical and acoustic pulses. From period histograms over a recording interval of 1,000 ms, the driven firing rate to repetition rates from 2 to 38 Hz was obtained and repetition rate transfer functions (RRTFs) were constructed. The RRTFs were characterized as low-pass or band-pass filters and several descriptors were obtained, such as the repetition rate producing the highest driven activity, high and low cutoff frequencies 6 dB below maximum firing rate, and maximum firing rate. 3. For a given neuron, the main characteristics of cortical RRTFs obtained with electrical and acoustic cochlear stimulation were quite similar. However, some small but statistically significant differences in the best repetition rate, cutoff frequencies, and maximum firing rate could be observed between the different stimulation modes. The proportion of band-pass RRTFs was larger for electrical stimulation (57%) than for acoustic stimulation (41%). The high cutoff frequencies for electrical stimulation were slightly but consistently higher than for acoustic RRTFs of the same neuron and the maximum firing rate for electrical stimulation was significantly higher than that evoked by ipsilateral acoustic stimulation. 4. The entrainment of cortical neurons to electrical and acoustic pulses was determined and entrainment profiles were constructed. For a given neuron, electrical entrainment profiles showed higher cutoff frequencies than with acoustic stimulation when judged with a fixed entrainment criterion of 0.25 spikes per event. The maximum entrainment seen for electrical stimulation was approximately 20% higher than seen for the same neuron with acoustic stimulation. 5. Correlation analysis of repetition coding and latency parameters revealed several relationships between these response aspects. Most prominent among them was a significant correlation between measures of the response latency and estimates of the ability to follow temporal repetitions for acoustic as well as electrical conditions. 6. Parametric and comparative evaluations of cortical responses to acoustic and electrical cochlear stimulation support the conclusion that the temporal resolution seen in cortical neurons is largely a consequence of central processing mechanisms based on cell and circuit properties and to a lesser degree a consequence of particular spatial and temporal peripheral excitation patterns. The slightly higher temporal resolution found for the electrical stimulation modes suggests that the temporally highly coherent electrical stimulation appears to engage, in a more effective manner, the excitatory/inhibitory mechanisms contributing to the response in AI than acoustic click stimulation with less temporal coherence. (ABSTRACT TRUNCATED)

Acoustic Stimulation↗
PubMed2003

Causes of electrical deaths and injuries among construction workers.

BACKGROUND: Contact with electrical current is the fourth leading cause of deaths of construction workers. This study evaluates electrical deaths and injuries to construction workers. METHODS: Two sources of data were analyzed in detail: (1) 1,019 electrical deaths identified by the Bureau of Labor Statistics, Census of Fatal Occupational Injuries (CFOI) for the years 1992-1998; and (2) 61 electrical injuries identified between November 1, 1990 and December 31, 1998 from a George Washington University Emergency Department injury surveillance database. RESULTS: Contact with "live" electrical wiring, equipment, and light fixtures was the main cause of electrical deaths and injuries among electrical workers, followed by contact with overhead power lines. Among non-electrical workers, contact with overhead power lines was the major cause of death. Other causes included contact with energized metal objects, machinery, power tools, and portable lights. Arc flash or blast caused 31% of electrical injuries among construction workers, but less than 2% of electrical deaths. CONCLUSION: Adoption of a lockout/tagout standard for construction, and training for non-electrical workers in basic electrical safety would reduce the risk of electrical deaths and injuries in construction. Further research is needed on ways to prevent electrical deaths and injuries while working "live".

Cause of Death↗
PubMed1985

Continuous electrical activity during sustained monomorphic ventricular tachycardia. Observations on its dynamic behavior during the arrhythmia.

Catheter mapping was performed during sinus rhythm and monomorphic ventricular tachycardia (VT) in 56 consecutive patients with sustained, monomorphic VT. Forty-two patients had an old myocardial infarction (VT-old MI group), 6 patients had right ventricular dysplasia (VT-RV dysplasia group), and 8 patients had idiopathic VT (idiopathic-VT group). Continuous electrical activity was recorded in 15 of 42 patients of the VT-old MI group (36%), 5 of 6 of the VT-RV dysplasia group (83%), and in 0 of 8 patients in the idiopathic VT group (0%). In 17 of 20 patients with continuous electrical activity during VT, observations on the dynamic behavior of continuous electrical activity during VT revealed at least 1 of the following characteristics: spontaneous disappearance and reappearance of continuous electrical activity without changes in rate, morphologic pattern or axis of VT; pacing-induced transient termination of continuous electrical activity without termination of VT; spontaneous disappearance of continuous electrical activity during VT as a rate-dependent phenomenon; Wenckebach-like conduction to other areas resulting in transient and periodic continuous electrical activity; dependence of continuous electrical activity on ventricular activation pattern during VT; pacing-induced change from a noncontinuous electrogram into continuous electrical activity without prevention of termination of VT; and termination of continuous electrical activity after antiarrhythmic drugs without termination of VT. Continuous electrical activity was always recorded in the aneurysm and never over normal heart areas. At the sites where continuous electrical activity was recorded during VT, potentials recorded during sinus rhythm were abnormal. Our observations suggest that several electrophysiologic phenomena can simulate continuous electrical activity during monomorphic VT. Transient, continuous electrical activity is a frequent phenomenon that represents electrical activity from abnormal areas not necessarily required to perpetuate VT.

Anti-Arrhythmia Agents↗
PubMed2005

Electric dipole theory and thermodynamics of actomyosin molecular motor in muscle contraction.

Movements in muscles are generated by the myosins which interact with the actin filaments. In this paper we present an electric theory to describe how the chemical energy is first stored in electrostatic form in the myosin system and how it is then released and transformed into work. Due to the longitudinal polarized molecular structure with the negative phosphate group tail, the ATP molecule possesses a large electric dipole moment (p(0)), which makes it an ideal energy source for the electric dipole motor of the actomyosin system. The myosin head contains a large number of strongly restrained water molecules, which makes the ATP-driven electric dipole motor possible. The strongly restrained water molecules can store the chemical energy released by ATP binding and hydrolysis processes in the electric form due to their myosin structure fixed electric dipole moments (p(i)). The decrease in the electric energy is transformed into mechanical work by the rotational movement of the myosin head, which follows from the interaction of the dipoles p(i) with the potential field V(0) of ATP and with the potential field Psi of the actin. The electrical meaning of the hydrolysis reaction is to reduce the dipole moment p(0)-the remaining dipole moment of the adenosine diphosphate (ADP) is appropriately smaller to return the low negative value of the electric energy nearly back to its initial value, enabling the removal of ADP from the myosin head so that the cycling process can be repeated. We derive for the electric energy of the myosin system a general equation, which contains the potential field V(0) with the dipole moment p(0), the dipole moments p(i) and the potential field psi. Using the previously published experimental data for the electric dipole of ATP (p(0) congruent with 230 debye) and for the amount of strongly restrained water molecules (N congruent with 720) in the myosin subfragment (S1), we show that the Gibbs free energy changes of the ATP binding and hydrolysis reaction steps can be converted into the form of electric energy. The mechanical action between myosin and actin is investigated by the principle of virtual work. An electric torque always appears, i.e. a moment of electric forces between dipoles p(0) and p(i)(/M/ > or = 16 pN nm) that causes the myosin head to function like a scissors-shaped electric dipole motor. The theory as a whole is illustrated by several numerical examples and the results are compared with experimental results.

Actomyosin↗
PubMed1993

Exposure assessment for power frequency electric and magnetic fields.

Over the past decade considerable data have been collected on electric and magnetic fields in occupational environments. These data have taken the form of area measurements, source characterizations, and personal exposure measurements. Occupational EMF levels are highly variable in space and time. Exposures associated with these fields exhibit similar large variations during a day, between days, and between individuals within a group. The distribution of exposure measures is skewed over several decades with only a few values occurring at the maximum field levels. The skewness of exposure measures implies that large sample sizes may be required for assessments and that multiple statistical descriptors are preferred to describe individual and group exposures. Except for the relatively few occupational settings where high voltage sources are prevalent, electric fields encountered in the workplace are probably similar to residential exposures. Consequently, high electric field exposures are essentially limited to utility environments and occupations. Within the electric utility industry, it is definitely possible to identify occupations with high electric field exposures relative to those of office workers or other groups. The highly exposed utility occupations are linemen, substation operators, and utility electricians. The distribution of electric field exposures in the utility worker population is very skewed even within a given occupation. As with electric fields, magnetic fields in the workplace appear to be comparable with residential levels, unless a clearly defined high-current source is present. Since high-current sources are more prevalent than high-voltage sources, environments with relatively high magnetic field exposures encompass a more diverse set of occupations than do those with high electric fields. Within the electric utility industry, it is possible to identify occupational environments with high magnetic field exposure relative to the office environment. Utility job categories with the highest exposures are generation facility workers, substation operators, utility linemen, and utility electricians. There are also higher exposures among traditional "electrical worker" job categories. Outside the electrical utility industry, potential sources of high occupational magnetic field exposures at ELF are induction furnaces, welding machines, electrical transportation systems, and electrical distribution vaults. However, the use of low power electrical equipment such as small motors in close proximity to workers and possibly for long periods of time could also lead to high exposure situations. Handheld survey instruments are available to perform area measurements of electric and magnetic fields at power frequencies but not aat all frequencies within the ELF range. Sophisticated personal computer-based instruments are available to characterize areas and sources across the entire frequency range.(ABSTRACT TRUNCATED AT 400 WORDS)

Electromagnetic Fields↗
PubMed1995

Postjunctional alpha 1- and beta-adrenoceptor effects of noradrenaline on electrical slow waves and phasic contractions of cat colon circular muscle.

1. The postjunctional excitatory and inhibitory effects of noradrenaline and selective alpha 1- and beta-adrenoceptor agonists on electrical and mechanical activity of cat colon muscle strips were studied by microelectrode recordings and isometric force measurements. Experiments were performed in the presence of tetrodotoxin (0.5 microM) or atropine (0.5 microM). 2. Circular muscle cells near the submucosal border had a mean resting membrane potential of -76.1 +/- 1.2 mV and exhibited electrical slow waves at frequencies of 4-6 cycles min-1. The mean values of electrical slow wave components were: upstroke potential, -40.7 +/- 1.2 mV; plateau potential, -43.7 +/- 0.8 mV; and duration, 4.9 +/- 0.4 s. Electrical slow waves were in phase with rhythmic contractions of the circular muscle layer. Muscle cells near the myenteric border had a mean testing membrane potential of -51.1 +/- 5.5 mV and did not exhibit electrical slow waves. 3. Noradrenaline (1 microM) increased the duration of electrical slow waves. This effect was inhibited by prazosin (1 microM) and potentiated by propranolol (5 microM), indicating activation of alpha 1- and beta-adrenoceptors. Also, when alpha 1-adrenoceptors were irreversibly blocked by phenoxybenzamine (1 microM), noradrenaline decreased the duration of electrical slow waves. Phenylephrine (1 microM), a selective alpha 1-adrenoceptor agonist, and isoprenaline (1 microM), a beta-adrenoceptor agonist, increased or decreased the duration of electrical slow waves, respectively. 4. Phenylephrine (0.01-5 microM) caused a linear increase in the area of electrical slow waves and phasic contractions but did not affect resting membrane potential or resting muscle tension. Higher concentrations of phenylephrine (5-50 microM) depolarized the resting membrane potential (2-6 mV) and increased muscle tone. 5. Nitrendipine or verapamil (each at 5 microM) reduced the amplitude of the upstroke potential and nearly abolished the plateau phase of the electrical slow waves. In the presence of L-type Ca2+ antagonists, noradrenaline (1-10 microM) or phenylephrine (1-100 microM) had no effect on electrical slow waves and phasic contractions. This indicates that the effects of noradrenaline and phenylephrine involve the influx of extracellular Ca2+ through voltage-dependent L-type Ca2+ channels. 6. Ryanodine, an alkaloid that depletes intracellular Ca2+ stores nearly abolished phasic contractions. In muscle strips, pretreated with ryanodine (10 microM for 30 min), phenylephrine (1 microM) increased and isoprenaline (1 microM) decreased the duration of electrical slow waves but neither was able to reverse the ryanodine-suppressed phasic contractions. This suggests that adrenoceptor effects on electrical slow waves are coupled to contractions via Ca2+ release from ryanodine-sensitive intracellular stores. 7. In summary, noradrenaline activates postjunctional alpha 1- and beta-adrenoceptors. Activation of alpha 1-adrenoceptors increases the magnitude of electrical slow waves and phasic contractions, whereas activation of beta-adrenoceptors decreases them. The alpha 1-adrenoceptor mediated effects on electrical slow waves and phasic contractions require the influx of Ca2+ through voltage-gated L-type Ca2+ channels. Phasic contractions also involve Ca2+ release from ryanodine-sensitive intracellular stores.

Adrenergic alpha-Agonists↗
PubMed1996

Electrically evoked cubic distortion product otoacoustic emissions from gerbil cochlea.

It has been demonstrated that electrical stimulation of the cochlear partition results in basilar membrane vibration and otoacoustic emissions. Electromotility of stimulated outer hair cells (OHCs) elicits the electrically evoked otoacoustic emissions (EEOAEs). Although electrically evoked upper and lower sideband distortion products (DPs) have been reported, electrically evoked cubic DP has not been investigated. Since the acoustically evoked cubic DP is the most commonly used otoacoustic measure of cochlear nonlinearity, this study tested whether electrical stimuli evoke a cubic DP otoacoustic emission. An electrical current containing the frequency component f1 and f2 (f1 < f2) was delivered to the round window niche of the gerbil, and electrically induced sound pressure change in the external ear canal was measured with a microphone. It was found that, in addition to f1 and f2 EEOAEs, cubic DP (2f1-f2) and other emissions at 3f1-2f2, 2f2-f1 and f2-f1 frequencies are electrically evoked. The electrically evoked cubic DP growth is similar to that of an acoustically evoked cubic DP. An electrical stimulus at f1 or f2 and an acoustic stimulus at f2 or f1 produce an identical cubic DP to that evoked by two electrical stimuli and/or two acoustic stimuli at f1 and f2 frequencies. An acoustic suppressor at a frequency near f2 can completely suppress an electrically evoked cubic DP emission. These data demonstrate that DPs can be provoked by a complex two frequency electrical current delivered to the round window niche. These stimuli elicit mechanical vibrations, from stimulated OHCs near the round window, which propagate apically toward their characteristic frequency places on the basilar membrane, and produce combination DPs. Electrically evoked cubic DPs appear to be produced by the same nonlinear mechanism that generates acoustically evoked DPs.

Acoustic Stimulation↗
PubMed1996

Impedance method computation of induced currents in a simple model of a child exposed to electromagnetic fields of an electric blanket.

The three dimensional impedance method has been used to calculate the distribution of induced current densities in a simple model of an 8-y-old child exposed to the electric and magnetic fields of an electric blanket. Two types of electric blankets have been modeled in the calculations, the pre-1989 conventional type and the presently available low magnetic field PTC (positive temperature coefficient) electric blanket. The purpose of this study was to calculate and compare the induced current densities in the model of the child due to the two types of blankets and also to compare the contributions to the induced currents by the electric and magnetic fields produced by the two types of blankets. The computations have shown that as expected and claimed, the induced current density in the model of the child due to the magnetic field of the low magnetic field PTC electric blanket is much lower than the induced current density due to the magnetic field of the conventional electric blanket. However, the computations have also shown that the contribution to the total current density by the electric field of the low magnetic field electric blanket is slightly higher than that due to the electric field of the conventional electric blanket. Hence, the total average induced current density due to both the electric and magnetic fields in the case of the low magnetic field PTC electric blanket is about one-third that in the case of the conventional electric blanket.

Bedding and Linens↗
PubMed1982

Electrical and contractile activities of the human rectosigmoid.

Electrical and mechanical activities were recorded from the rectosigmoid of normal subjects using an intraluminal recording tube with two sets of bipolar electrodes and strain gauges. Four distinct types of electrical activities were recorded. (1) Electrical control activity (ECA). This activity varied in amplitude and frequency over time and the control waves were not phase-locked. The means of dominant frequency components in the lower and higher frequency ranges were 3.86 +/- 0.18 SD and 10.41 +/- 0.46 SD c/min, respectively. The overall dominant frequency component was mostly in the lower frequency range of 2.0-9.0 c/min. (2) Discrete electrical response activity (DERA). This activity appeared as short duration bursts (less than 10 s) of response potentials whose repetition rate was in the total colonic electrical control activity frequency range of 2.0-13.0 c/min. The mean duration of this activity was 2.24 +/- 1.30 SD s. (3) Continuous electrical response activity (CERA). This activity appeared as long duration bursts (greater than 10 s) of response potentials which were not related to electrical control activity. Its mean duration was 14.78 +/- 3.68 SD s. This activity generally did not propagate. (4) Contractile electrical complex (CEC). This activity appeared as oscillations in the frequency range of 25-40 c/min and was also not related to electrical control activity. This activity propagated, sometimes proximally and sometimes distally. Its mean duration was 18.87 +/- 9.22 SD s. The latter three types of electrical activities were all associated with different types of contractions. These contractions, however, did not always occlude the lumen. Colonic electrical control activity controls the appearance of discrete electrical response activity in time and space. The mechanism of generation of continuous electrical response activity and contractile electrical complex is not yet known.

Adolescent↗
PubMed1993

Introduction to power-frequency electric and magnetic fields.

This paper introduces the reader to electric and magnetic fields, particularly those fields produced by electric power systems and other sources using frequencies in the power-frequency range. Electric fields are produced by electric charges; a magnetic field also is produced if these charges are in motion. Electric fields exert forces on other charges; if in motion, these charges will experience magnetic forces. Power-frequency electric and magnetic fields induce electric currents in conducting bodies such as living organisms. The current density vector is used to describe the distribution of current within a body. The surface of the human body is an excellent shield for power-frequency electric fields, but power-frequency magnetic fields penetrate without significant attenuation; the electric fields induced inside the body by either exposure are comparable in magnitude. Electric fields induced inside a human by most environmental electric and magnetic fields appear to be small in magnitude compared to levels naturally occurring in living tissues. Detection of such fields thus would seem to require the existence of unknown biological mechanisms. Complete characterization of a power-frequency field requires measurement of the magnitudes and electrical phases of the fundamental and harmonic amplitudes of its three vector components. Most available instrumentation measures only a small subset, or some weighted average, of these quantities. Hand-held survey meters have been used widely to measure power-frequency electric and magnetic fields. Automated data-acquisition systems have come into use more recently to make electric- and magnetic-field recordings, covering periods of hours to days, in residences and other environments.(ABSTRACT TRUNCATED AT 250 WORDS)

Electromagnetic Fields↗