Action Of Electromagnetic Field Research Articles

Solution of the connected problem of thermomechanics for a long hollow electroconductive cylinder under the action of impulsed electromagnetic field with amplitude modulation

Solution of the connected problem of thermomechanics for a long hollow electroconductive cylinder under the action of impulsed electromagnetic field with amplitude modulation

Thermoelastic processes analyzer for piecewise homogeneous conductive structures subjected to pulsed electromagnetic actions

A mathematical model is suggested for the determination of thermal stress state, load-bearing capacity, and properties of a contact joint of the components of a piecewise homogeneous conductive solid under the action of pulsed electromagnetic fields. The basic relationships of thermomechanics for such a solid are presented in terms of displacements and stresses. The boundary conditions are formulated for the key functions both at the outer surfaces of the solid and at the surfaces of its components contact.

Correction: Exposure to 1.8 GHz electromagnetic fields affects morphology, DNA-related Raman spectra and mitochondrial functions in human lympho-monocytes.

[This corrects the article DOI: 10.1371/journal.pone.0192894.].

Effects of Prenatal Combined Stress on Passive Avoidance Learning and Memory in Rats

The effects of combined prenatal stress (including the action of electromagnetic fields, zoo social stress, and immobility on pregnant females) on the learning and memory of offsprings of rats were investigated. Two groups of male and female rats (n = 16 in each) were studied. The animals received prenatally (from 8 to 18 days of gestation) three different stresses as follows: immobilization of pregnant mothers (0.5 h, twice a day by placing in a restrainer), social stress (6 rats kept in a small cage), and exposure to electromagnetic waves (4 h, 0.5 MT, 50 Hz). The learning and memory of rats were assessed two months after birth (2, 6, 24, 48 h and 1- and 2-week-long intervals after training) by using a conditioning avoidance method. Also, expression of the APP gene was investigated in rats using RT-PCR. The prenatal stress suppressed visits of male offsprings to the dark compartment in comparison with the control group, and the difference was significant 2 h after the shock (P 0.05).The relative expression of the APP gene was also higher in both male and female offsprings (P < 0.05 and 0.01, respectively). Thus, the implemented combined prenatal stress impaired the acquisition process and long-term memory in male offsprings and long-term memory in female offsprings. Also, it may promote deposition of β-amyloid plaques.

Exposure to 1.8 GHz electromagnetic fields affects morphology, DNA-related Raman spectra and mitochondrial functions in human lympho-monocytes.

Blood is a fluid connective tissue of human body, where it plays vital functions for the nutrition, defense and well-being of the organism. When circulating in peripheral districts, it is exposed to some physical stresses coming from outside the human body, as electromagnetic fields (EMFs) which can cross the skin. Such fields may interact with biomolecules possibly inducing non thermal-mediated biological effects at the cellular level. In this study, the occurrence of biochemical/biological modifications in human peripheral blood lympho-monocytes exposed in a reverberation chamber for times ranging from 1 to 20 h to EMFs at 1.8 GHz frequency and 200 V/m electric field strength was investigated. Morphological analysis of adherent cells unveiled, in some of these, appearance of an enlarged and deformed shape after EMFs exposure. Raman spectra of the nuclear compartment of cells exposed to EMFs revealed the onset of biochemical modifications, mainly consisting in the reduction of the DNA backbone-linked vibrational modes. Respirometric measurements of mitochondrial activity in intact lympho-monocytes resulted in increase of the resting oxygen consumption rate after 20 h of exposure, which was coupled to a significant increase of the FoF1-ATP synthase-related oxygen consumption. Notably, at lower time-intervals of EMFs exposure (i.e. 5 and 12 h) a large increase of the proton leak-related respiration was observed which, however, recovered at control levels after 20 h exposure. Confocal microscopy analysis of the mitochondrial membrane potential supported the respiratory activities whereas no significant variations in the mitochondrial mass/morphology was observed in EMFs-exposed lympho-monocytes. Finally, altered redox homeostasis was shown in EMFs-exposed lympho-monocytes, which progressed differently in nucleated cellular subsets. This results suggest the occurrence of adaptive mechanisms put in action, likely via redox signaling, to compensate for early impairments of the oxidative phosphorylation system caused by exposure to EMFs. Overall the data presented warn for health safety of people involved in long-term exposure to electromagnetic fields, although further studies are required to pinpoint the leukocyte cellular subset(s) selectively targeted by the EMFs action and the mechanisms by which it is achieved.

The Impact of Electromagnetic Field on Conditioned Reflex Memory

The aim of this study is to investigate whether household frequency electromagnetic field affect memory processes. Apparently in various studies researchers note that different frequencies electromagnetic field improve or impair memory. In memory process hormone ghrelin plays an important role, which participates in the neurogenesis processes of memory formation. We have studied effect of electromagnetic field (EMF) on ghrelin`s concentration and memory changes under EMF. We exposed male Wistar rats under EMF. The household frequency electromagnetic field was generated with a GSM mobile phone. For memory tests we used the two feeder and five choice serial reaction time tests (5-CSRTT). With this latter test we studied attention and concentration and in serum we measured the concentration of ghrelin by immunoferminal analysis. In serum ghrelin concentration increased in electromagnetic field exposure group, after 30th day of the exposure level of ghrelin is higher than after 10 day of exposure and the sham control group. During training EMF exposure group rats task needed more trials (sessions) than in sham control group (in 5-CSRTT in sham control and EMF exposure groups, the values were 92,9±2,084 and 101,8±2,764, respectively. n=10; p＜0.05, in two feeder tests in sham control and EMF exposure groups, the values were 82,7±2,989 and 99,1±3,903, respectively. n=10; p＜0.05). As for memory consolidation, for performing 5-CSRTT after 30 day of EMF action we received significant differences in the number of correctly performed tasks (sham control and EMF exposure groups, the values were 0,7±0,1528 and 0,2±0,1333, respectively; p＜0.05) and results in prematurity activities (in sham control and EMF exposure groups 0,5 ± 0,2236 and 1,5 ± 0,3416, p＜0.05) and in accuracy (in sham control and EMF exposure groups 0,5 ± 0,1667and 1,4 ± 0,2667, p＜0.05). In our study It was found, that EMF affected as well as on learning and memory recall process, but with more advanced research reason, that clinically gave a picture of memory loss mainly related to decreased attention and concentration, which is also confirmed by the increase in concentration of hormone ghrelin, participating in memory processes, under influence of the household frequency EMF.

Изменение электрокинетических показателей ядер клеток буккального эпителия под действием электромагнитных полей миллиметрового диапазона

Изменение электрокинетических показателей ядер клеток буккального эпителия под действием электромагнитных полей миллиметрового диапазона

Thermokinetic model of fracture of heterogeneous materials and peculiarities of its numerical realization under the action of RF electromagnetic fields

The fracture of rocks has been investigated theoretically and experimentally. The model of evolution of micro- and macrocracking under the action of electromagnetic fields with the help of rf electrodes has been proposed. The calculation of the fields of temperature and thermoelastic stresses makes it possible to study the evolution of macrocracking and to establish the directions of evolution in the case of their 3D configuration. The mechanisms of the formation of a main crack for regions with different tensile stresses have been established. The main crack can evolve towards the range of tensile stresses lower than the ultimate tensile stress. The possibility of controlling the evolution of the main crack by selecting stresses over the length of the crack formed and the heating time has been demonstrated.

Contact deformation of the compound coil with an assistant screen under the action of electromagnetic field

The paper discusses issues concerning the deformation of a system of conductive bodies under the action of the electromagnetic field. Problem of nonlinear deformation of the compound coil with an assistant for electromagnetic forming of sheet workpieces is considered as a practical application. The problem is solved by the finite element method. Contact interaction is modeled by the introduction of special layers of contact finite elements. Spatial-temporal distributions of the main components of the electromagnetic field are obtained. The ability to review the problem of deformation in the quasi-stationary formulation is justified. The distribution of the main component of the stress-strain state is presented. The influence of the current magnitude at the maximum stresses is evaluated.

A Universal Condition Satisfied by the Action of Electromagnetic Radiation Fields

The action (the product of radiated energy and the time of emission) of the radiation fields generated by four types of radiators, namely, short electric dipole, small magnetic dipole, travelling wave antenna and bi-conical antenna is investigated with special reference to the charge associated with the current waveform which is responsible for the radiation. The results obtained can be summarized by the order of magnitude inequality where A is the action (product of the radiated energy and the time of emission), h is the Planck constant, q is the charge associated with the current that gave rise to the radiation and e is the electronic charge. The condition is obtained when the length of the antenna and its radius are pushed to its extreme natural limits. Based on the results obtained here and elsewhere, it is suggested that this inequality is valid in general for electromagnetic radiation fields as predicted by classical electrodynamics.

Electromagnetic fields for the treatment of osteoarthritis: A review of potential clinical applications

Osteoarthritis (OA) is a common disorder of the musculoskeletal system and a major burden on healthcare systems worldwide. Different modalities have been developed for the treatment and management of OA. In recent years, electromagnetic fields (EMFs) have shown positive therapeutic effects in this disorder. Several studies have investigated the effectiveness of different EMFs for the treatment of OA with controversial but promising outcomes. This study aims to comprehensively review the recent advances in applications of EMFs for the treatment of OA as alternative or adjunctive treatment. In addition, the mechanisms of action of EMFs in exerting therapeutic outcomes as well as clinical perspectives are discussed.

Elastoplastic Deformation of Bodies Interacting Through Contact Under the Action of Pulsed Electromagnetic Field

A formulation is presented for the problem of elastoplastic deformation of the system of electrically conductive bodies under the action of pulsed electromagnetic field. The numerical technique for solving the problem is based on the finite element method. Deformation of bodies interacting through contact during the pulsed magnetic treatment of materials is analyzed. The influence of the manufacturing and design parameters of the inductor–workpiece system on its stress-strain state is investigated.

ВПЛИВ ІМПУЛЬСНОГО ЕЛЕКТРОМАГНІТНОГО ПОЛЯ НА ЖИТТЄЗДАТНІСТЬ ESCHERICHIA COLI В МОДЕЛЬНОМУ РОЗЧИНІ МОЛОЧНОЇ СИРОВАТКИ

Важливим показником мікробіологічної безпечності та якості, а також рівня санітарно-гігієнічних умов виробництва є бактерії групи кишкових паличок . При перевищенні допустимого титру ці мікроорганізми можуть спричиняти псування готового продукту і навіть харчові отруєння. В проблемно науково-дослідній лабораторії Національного університету харчових технологій були проведені експерементальні дослідження з метою вивчення дії впливу імпульсних електромагнітних полів на ентеробактерії, а саме культури Escherichia coli в модельному розчині молочної сироватки.&#x0D; При проведенні досліджень використовувалася експериментальна установка, яка розроблена фахівцями в НТУ «Харківський Політехнічний Інститут». Для диференціації Escherichia coli використовувалося середовище Ендо, у якому ці бактерії давали характерний ріст у вигляді колоній червоного кольору з метелевим блиском. Модельні розчини молочної сироватки обробляли при напрузі 15…30 кВт/см3, з тривалістю обробки 10…20 с. Результати мікробіологічних досліджень модельного розчину сироватки молочної підтверджені комунальним підприємством «Санепідсервісом» м. Харкова.&#x0D; При дослідженнях встановлено, що обробка електромагнітними імпульсами з напругою 30 кВт/см3 протягом 20 с є найбільш ефективною, оскільки спостерігається повна інактивація клітини Escherichia coli внесеної до молочної сироватки.&#x0D; Доведено можливість здійснення теплового оброблення молочної сироватки за рахунок нетеплових ефектів, що виникають за імпульсної дії електричних полів. Відкрито перспективи використання вітчизняних ІЕП-установок при первинному обробленні молочної сироватки з метою знищення мікроорганізмів.&#x0D;

Jet engine with electromagnetic field excitation of expendable solid-state material

Electromagnetic field action on a solid-state natural raw material is considered here in the context of producing a mechanical reactive momentum. We suggest the development of a jet engine that possesses fast control and low thrust based on desorption or sputtering of particles flow from a solid surface.

Influences of Electromagnetic Energy on Bio-Energy Transport through Protein Molecules in Living Systems and Its Experimental Evidence.

The influences of electromagnetic fields (EMFs) on bio-energy transport and its mechanism of changes are investigated through analytic and numerical simulation and experimentation. Bio-energy transport along protein molecules is performed by soliton movement caused by the dipole–dipole electric interactions between neighboring amino acid residues. As such, EMFs can affect the structure of protein molecules and change the properties of the bio-energy transported in living systems. This mechanism of biological effect from EMFs involves the amino acid residues in protein molecules. To study and reveal this mechanism, we simulated numerically the features of the movement of solitons along protein molecules with both a single chain and with three channels by using the Runge–Kutta method and Pang’s soliton model under the action of EMFs with the strengths of 25,500, 51,000, 76,500, and 102,000 V/m in the single-chain protein, as well as 17,000, 25,500, and 34,000 V/m in the three-chain protein, respectively. Results indicate that electric fields (EFs) depress the binding energy of the soliton, decrease its amplitude, and change its wave form. Also, the soliton disperses at 102,000 V/m in a single-chain protein and at 25,500 and 34,000 V/m in three-chain proteins. These findings signify that the influence of EMFs on the bio-energy transport cannot be neglected; however, these variations depend on both the strength and the direction of the EF in the EMF. This direction influences the biological effects of EMF, which decrease with increases in the angle between the direction of the EF and that of the dipole moment of amino acid residues; however, randomness at the macroscopic level remains. Lastly, we experimentally confirm the existence of a soliton and the validity of our conclusion by using the infrared spectra of absorption of the collagens, which is activated by another type of EF. Thus, we can affirm that both the described mechanism and the corresponding theory are correct and that EMFs or EFs can influence the features of energy transport in living systems and thus have certain biological effects.

Electromagnetic Fields Act Similarly in Plants as in Animals: Probable Activation of Calcium Channels via Their Voltage Sensor

It has been shown that low intensity microwave/lower frequency electromagnetic fields (EMFs) act in animals via activation of voltage-gated calcium channels (VGCCs) in the plasma membrane, producing excessive intracellular calcium [Ca2+]i, with excessive [Ca2+]i leading to both pathophysiological and also in some cases therapeutic effects. The pathophysiological effects are produced largely through excessive [Ca2+]i signaling including excessive nitric oxide (NO), superoxide, peroxynitrite, free radical formation and consequent oxidative stress. The activation of the VGCCs is thought to be produced via EMF impact on the VGCC voltage sensor, with the physical properties of that voltage sensor predicting that it is extraordinarily sensitive to these EMFs. It is shown here that the action of EMFs in terrestrial, multicellular (embryophyte) plants is probably similar to the action in animals in most but not all respects, with calcium channel activation in the plasma membrane leading to excessive [Ca2+]i, leading in turn to most if not all of the biological effects. A number of studies in plants are briefly reviewed which are consistent with and supportive of such a mechanism. Plant channels most plausibly to be involved, are the so-called two pore channels (TPCs), which have a voltage sensor similar to those found in the animal VGCCs. Keywords: Microwave frequency non-thermal effects, calcium signaling, ion channel evolution, EMFs as an environmental stressor, free radicals including hydroxyl, carbonate and NO2 radicals.

Computational challenges in magnetic-confinement fusion physics

Magnetic-fusion plasmas are complex self-organized systems with an extremely wide range of spatial and temporal scales, from the electron-orbit scales (∼10−11 s, ∼ 10−5 m) to the diffusion time of electrical current through the plasma (∼102 s) and the distance along the magnetic field between two solid surfaces in the region that determines the plasma–wall interactions (∼100 m). The description of the individual phenomena and of the nonlinear coupling between them involves a hierarchy of models, which, when applied to realistic configurations, require the most advanced numerical techniques and algorithms and the use of state-of-the-art high-performance computers. The common thread of such models resides in the fact that the plasma components are at the same time sources of electromagnetic fields, via the charge and current densities that they generate, and subject to the action of electromagnetic fields. This leads to a wide variety of plasma modes of oscillations that resonate with the particle or fluid motion and makes the plasma dynamics much richer than that of conventional, neutral fluids. Simulating magnetically confined fusion plasmas is crucial to understand and control them. Here, the state of the art and the multi-physics involved are discussed: electromagnetism and hydrodynamics combined over vast spatiotemporal ranges.

Comparison of Therapeutic Magnetic Stimulation With Electric Stimulation of Spinal Column Vertebrae

Electrical bone growth stimulators improve patient outcomes following the spinal fusion surgery, particularly important in high-risk patient populations. The therapeutic electromagnetic field (EMF) effects in tissue were modeled for two Food and Drug Administration (FDA) approved magnetic stimulation devices: 1) Coil A (SpinaLogic, DJO LLC, Vista, CA) and 2) Coil B system (Spinal-Stim, Orthofix Inc., Lewisville, TX). The electric current density induced in the target tissue (spinal vertebra) was compared with that of an FDA approved electric stimulation device (SpinalPak, Biomet, Warsaw, IN). For Coil A and Coil B, the EMF source was current-carrying coils that differed in the design (single coil versus two coaxial coil system) and the current characteristics (continuous 76.6 Hz sinusoid, biased versus intermittent 3850 Hz rectangular pulse bursts repeated at 1.5 Hz, unbiased). The local maximum induced electric field and current density were over 700-fold higher for Coil B system than for Coil A but only half of the values calculated for the reference electric stimulation device. The interaction of the magnetic field and the induced current in the tissue gives rise to local Lorentz force effects expressed as magnetoacoustic pressure (MAP) that for Coil B system reached 5 dB relative to $1~\mu $ Pa of sound pressure level in bone (SPL) (compared with −45 dB for Coil A and absent for capacitive coupling reference device). The analysis broadens the range of possible mechanisms of therapeutic EMF action to include the MAP.

Effect of Herbal Extract of Polygonum Aviculare on Lipocalin 2 Expression After EMF Exposure in Mouse Testis

Introduction: Electromagnetic radiation has irreparable biological effects on various tissues including testis. The use of antioxidants can greatly reduce the effects of this radiation and has anti-oxidant properties but their mechanism is not clear. Therefore, in the present study, protective effects of herbal extract of polygonum aviculare which are rich in antioxidants components examined on the expression levels of lipocalin 2.Methods: Twenty four male mice, 8 weeks divided to 4 groups (one control and three experimental groups). Control group didn’t receive EMF exposure. EMF group mice received 3 mT EMF during 2 months, 4 hours daily and 5 days weekly. Polygonum aviculare group received 50 mg/kg herbal extract during 2 months and poly -EMF group received 3 mT EMF during 2 months, 4 hours daily and 5 days weekly and 50mg/kg herbal extract during 2 months. After 2 months the mice sacrificed by cervical dislocation and samples prepared from the testis and immunofluorescent techniques was used to determine lipocalin 2 expression levels.Results: the result showed that lipocalin 2 expression was decreased in EMF group and increased in mice which had received herbal extract of polygonum aviculare.Conclusions: As seen in the results, herbal extract increased lipocalin 2 expression and might act as a protective agent against free radicals induced by the action of electromagnetic field. Although, further studies are needed to acquire more knowledge about the mechanisms of these extracts.

Al doping effects on ZnO nanostructure and growth mechanism

High-energy and large surface Al-doped ZnO nanostructure arrays were fabricated using hydrothermal methods under the action of pulsed electromagnetic field. The morphology, structure and component features were analysed by field emission scanning electron microscopy, X-ray powder diffraction and X-ray photoelectron spectroscopy. Results showed that the hexagonal sheet like Al-doped ZnO regularly interlaced with each other and vertically grew on the FTO substrate. The surfaces of the ZnO nanosheets were larger than those of the undoped ZnO nanorods. In addition, the formation mechanism of Al-doped ZnO nanostructure was explained.