Static Electromagnetic Fields Research Articles

Нейросетевой анализ влияния внешних факторов на микроэлементный профиль и биомассу микрозелени Brássica júncea L.

Growing organic microgreens indoors requires a unified technological procedure with various external elicitors. The quality of seedlings depends on their ability to accumulate essential microelements. This research assessed the nutrient profile of mustard microgreens using the method of fractal calculation with repeating numerical series.
 The experiment involved mustard (Brássica júncea L.) of the Nika variety grown in a closed box for 15 days under aggregation with an intensive 16-h photocycle (440 µmoL m2/s). The plants were inoculated with the endomycorrhizal fungus Glomus mosseae. A solution of fulvic acids (100 mg/L) served as a stabilizing organic additive and was introduced into the coconut substrate. The physical treatment included weak static electromagnetic field with magnetic induction (20 mT). The elemental analysis was performed by inductively coupled plasma atomic emission spectrometry on an ICPE-9000 device (Shimadzu, Japan).
 According to the calculated indices of the microelement biocomposition, the best result belonged to the sample treated with fulvic acids and weak electromagnetic field (IndBcomL = 0.27). The resulting biomass of dry powder for elemental analysis was 10.2 g, which was twice as high as the values obtained in the control sample, not subjected to any external influences (5.2 g). All the variants with mycorrhization produced no positive effect on the total pool of microelements during vegetation. 
 The increase in biomass averaged as low as 20%. Zinc increased by 33.3% while aluminum and iron decreased by 59.5 and 18.0%, respectively.
 The neural network analysis of the microelements in mustard microgreens proved effective as a mathematical model for biochemical diagnostics of biomass quality. The method could be used to optimize the biotechnological process for other indoor crops as it makes it possible to partially substitute mineral fertilizers with organic and bacterial complex.

Planckian effects on Ising model in an external electric field

In this article, we study Planckian effects on statistical thermodynamic properties of one dimensional polarized Ising model with an external electric field. We introduce Planckian effects by rewriting the Lagrangian of a static electromagnetic field in terms of deformed operators to obtain the corrected Lagrangian for a static electric field, and then deduce the corrected static electric field. Then we write down the corrected Ising model Hamiltonian in terms of the corrected static electric field. Corrected quantities such as the mean energy, Helmholtz free energy, and entropy are derived using the corrected Ising model Hamiltonian. Also, corrected quantities such as the polarization, dielectric constant, and polarizability tensor are derived. The expressions for the upper bounds of the deformation parameter α and the minimal length are written in terms of the dielectric constant. Using some experimental inputs we obtain the upper bound on the minimal length.

Effect of a critical magnetic field on the control of scalar neutral boson pair production in the context of Lorentz-symmetry violation

This study investigates the production of neutral scalar boson pairs in static electromagnetic fields resulting from Lorentz-symmetry violation (LSV), with a focus on the parity-even sector of the CPT-even photon sector in the Standard Model Extension (SME). Utilizing a cross-configuration involving inhomogeneous static electric fields and homogeneous static magnetic fields, the analysis of the probability of bosons pair production identifies three different regimes determined by a critical magnetic field. Below the critical value, creation is exponentially suppressed; at the critical value, the number density of created bosons remains constant, and above the critical field, there is exponential amplification. This behavior prompts an additional investigation using von Neumann entanglement entropy to analyze fluctuations in the bosonic vacuum.

Dirac materials in parallel electromagnetic fields generated by supersymmetry

In a Supersymetric Quantum Mechanics framework, the Dirac equation describing a Dirac material in the presence of electromagnetic fields is solved. Considering parallel static non-uniform electromagnetic fields, the Dirac equation is transformed into a two-dimensional system of equations. By means of variable separation, we can define one-dimensional eigenfunctions, which are solutions for two pairs of supersymmetric partner Schrödinger-like Hamiltonians. For Pöschl-Teller-like quantum potentials, we look for conditions that guarantee the existence of bound states, and determine an analytic zero-mode solution for the Dirac equation.

On the Physical Significance of the Helmholtz Theorem in a Static Electromagnetic Field

On the Physical Significance of the Helmholtz Theorem in a Static Electromagnetic Field

Physics-Informed Neural Networks for Solving 2-D Magnetostatic Fields

Physics-informed neural network (PINN) has shown great potential in the inverse and parametric designing problems in electrical engineering. Moreover, most existing works on PINN are dedicated to computational fluids, and very few attentions have been paid to static and low-frequency electromagnetic near fields with multiple media in electrical engineering applications. In this work, a PINN for solving two-dimensional (2D) magnetostatic fields in electromagnetic devices and systems is proposed. The magnetic field intensity and the magnetic vector potential are solved by training a neural network which encodes partial differential equations and boundary conditions as residuals. The computation of the spatial derivatives of media constitutive parameters, which negatively impacts the training of PINN, is eliminated. A mesh-assisted non-uniform sampling method for the selection of collocation points is proposed to further improve the performance of PINN. The proposed PINN is verified by comparing its results with those of the finite element method in two 2D magnetostatic case studies. It is expected that this work will promote further applications of PINN in the modelling, numerical analysis, and parametric design of electromagnetic devices and systems.

Massive superfluid vortices and vortex necklaces on a planar annulus

We study a superfluid in a planar annulus hosting vortices with massive cores. An analytical point-vortex model shows that the massive vortices may perform radial oscillations on top of the usual uniform precession of their massless counterpart. Beyond a critical vortex mass, this oscillatory motion becomes unstable and the vortices are driven towards one of the edges. The analogy with the motion of a charged particle in a static electromagnetic field leads to the development of a plasma orbit theory that provides a description of the trajectories which remains accurate even beyond the regime of small radial oscillations. These results are confirmed by the numerical solution of coupled two-component Gross-Pitaevskii equations. The analysis is then extended to a necklace of vortices symmetrically arranged within the annulus.

Static electromagnetic field and recombinant human fibroblasts encoding miR-451 and miR-16 increased cell trans-differentiation to CD71+ and CD235a+ erythroid like progenitor.

Ex vivo blood production is an urgent need of most countries, and creating production protocols can save the lives of many patients. Despite the recent advances in blood production in ex vivo conditions, its high-scale production is not yet possible, and requires further studies. Therefore, by transfecting fibroblast cells with miR-16, and miR-451 genes, as well as applying low frequency electromagnetic fields (ELF-EMF) treatment, we tried to increase the differentiation of these cells into CD71+ and CD235a+ erythroid like progenitors. After preparation, and cultivation of human dermal transgenic fibroblast cells, they were transfected by Plenti3-hsa-miR451, Plenti3-hsa-miR16 and Plenti3-backbone inserted into E. coli Stbl4 genome. Then, transgenic fibroblast cells were treated with 10mT ELF-EMF every day for 20 minutes for 7 days. Using a flow cytometer, the expressions of CD71, and CD235a were studied in these cells, and the expressions of genes involved in hematopoiesis were studied using the RT-PCR technique. The results indicated an increase in the differentiation of fibroblast cells treated with 10mT ELF-EMF to erythroid like progenitors. Furthermore, the percentage of CD71+ and CD235a+ cells was the highest in irradiated cells encoding miR-16 and miR-451, which indicates their differentiation into erythroid like progenitors. Also, in the transgenic cells treated with ELF-EMF, an increase in the expressions of α-chain, β-chain, γ-chain and GATA1 genes was observed, which indicates the potential of these cells for hematopoiesis. However, there was no significant difference in the expression of CD34 and CD38 genes in these cell lines. Both ELF-EMF and upregulations of miR-16 and miR-451 lead to improved differentiation of fibroblast cells into erythroid like progenitors.

Linearity of minimally superintegrable systems in a static electromagnetic field

Fifteen three-dimensional classical minimally superintegrable systems in a static electromagnetic field are shown to possess hidden symmetries leading to their linearization, and consequently the corresponding subsets of maximally superintegrable subcases are also linearizable. These results are strengthening the conjecture that all three-dimensional minimally superintegrable systems are linearizable by means of hidden symmetries, even in the presence of a magnetic field.

Activating oil palm germination and improved survival of seedlings using a rotating magnetic field

Effects of magneto priming on stimulation of seed germination is widely known. The field which generates magnetized water used for priming can be static magnetic or electromagnetic fields. In this work, we present effect of magneto-priming generated by a rotating magnetic field to improve oil palm (Elaeis guineensis, Jacq.) germination of oil palm kernels. We developed a rotisserie-type magnetic field apparatus (MFA) to stimulate oil palm seed germination. The roller (rotisserie) device ensures an even dosage to an applied magnetic field. Only a 4 h’ dosage was required to stimulate germination. The magnetic treatment group started to germinate at 15 days. There was 50% germination after 22 ± 1 d with a maximum germination rate of about 6% d−1 and 100% germination after 37 d. The linearly determined maximum germination rate is about 4.93 ± 0.34% d−1, whereas the logistic model gives a higher estimate of 6.46 ± 0.04% d−1. The MFA rotisserie device is a significant improvement in rate of germination and overall germination percentage as well as growth of young seedlings of oil palm.

Time-dependent theory of optical electro- and magnetostriction

Electrostriction, the deformation of dielectric materials under the influence of an electric field, is of continuous interest in optics. The classic experiment by Hakim and Higham [Proc. Phys. Soc. 80, 190 (1962)] for a stationary field supports a different formula of the electrostrictive force density than the recent experiment by Astrath et al. [Light Sci. Appl. 11, 103 (2022)] for an optical field. In this work, we study the origin of this difference by developing a time-dependent covariant theory of optical force densities in photonic materials. When a light pulse propagates in a bulk dielectric, the field-induced force density consists of two parts: (i) The optical wave momentum force density ${\mathbf{f}}_{\mathrm{owm}}$ carries the wave momentum of light and drives forward a mass density wave of the covariant coupled field-material state of light. (ii) The optostrictive force density ${\mathbf{f}}_{\mathrm{ost}}$ arises from the atomic density dependence of the electric and magnetic field energy densities. It represents an optical Lorentz-force-law-based generalization of the electro- and magnetostrictive force densities well known for static electromagnetic fields and derived from the principle of virtual work. Since the work done by ${\mathbf{f}}_{\mathrm{ost}}$ is not equal to the change of the field energy density during the contraction of the material, we have to describe this difference with optostriction-related dissipation terms to fulfill the energy conservation. The detailed physical model of the dissipation is left for further work. The optostrictive force density can be understood in terms of field-induced pair interactions inside the material. Because of the related action and reaction effects, this force density cannot contribute to the net momentum transfer of the optical field. The theory is used to simulate the propagation of a Gaussian light pulse through a dielectric material. We calculate the electric and magnetic fields of the Gaussian light pulse from Maxwell's equations and simultaneously solve Newton's equation of motion of atoms to find how the velocity and displacement fields of atoms develop as a function of time under the influence of the field-induced force density.

Suppressing Vortex by Static Electromagnetic Field at the Last Stage of Ladle Steel Teeming Process

Suppressing Vortex by Static Electromagnetic Field at the Last Stage of Ladle Steel Teeming Process

What evidence exists of crop plants response to exposure to static magnetic and electromagnetic fields? A systematic map protocol

BackgroundIncreasing demand for food and concerns over the environmental impact of agriculture has prompted the search for alternatives to many conventional farming practices. Reports on exposing seeds and plants at various developmental stages to static magnetic field (SMF) and non-ionizing electromagnetic fields (EMF) as a form of priming indicate some positive effects on seed germinability, growth rate, resistance to stress conditions, and improved yield. However, there exist some inconsistent reported treatment protocols and contradictory study outcomes that make it difficult to draw objective conclusions on the potential use of SMF and EMF as sustainable alternatives to improving crop growth and yield. It is equally essential to understand any adverse effects of exposing plants to SMF and EMF considering the abundance of their sources in the environment. In order to provide a more coherent overview of how plants respond to exposure to SMF and EMF not only in their observed effects of agronomic importance but also in the mechanisms of action of SMF and EMF in plant cells, we prepare a systematic map.MethodsLiterature will be identified by searching six bibliographic databases and three web-based search engines using terms obtained from the population, exposure, and outcome parameters of the research question. Primary research published in peer-reviewed journals and grey literature will be the source for the evidence map. Studies eligible for inclusion may involve: food crops and related research model plants exposed to SMF or non-ionizing EMF; treatment at all plant developmental stages excluding post-harvest improvement of food crops; and the presence of control groups. Eligible literature will be screened at the title, abstract, and full text levels. The validity of studies will not be critically appraised for the evidence map. A process of double extraction and coding of relevant information from eligible literature will be conducted. Within the evidence map, relevant data will be presented in the forms of text, graphs, tables, and figures. This will illustrate research trends, bring clarity to the evidence base concerning clusters of sufficient findings and areas of significant gaps, and inform stakeholders in decisions concerning research planning and policy formulation.

Optimizing Design of Vortex Suppression Utilizing Static Electromagnetic Field during Steel Teeming from Ladle

Vortex slag entrapment during ladle teeming process causes liquid steel pollution, nozzle clogging, etc. Tangential velocity of molten steel is directly related to the vortex. Herein, the tangential velocity is reduced by the electromagnetic force generated by the interaction between a static electromagnetic field and the molten steel. Through the multiphysical field simulation, influences of the electromagnetic parameter, coil structure, coil position, and ladle structure on the vortex are investigated. Results demonstrate that magnetic induction intensity is proportional to the coil ampere‐turns, thereby affecting the vortex suppression. The action region of the static electromagnetic field expands when the coil diameter increases from 180 to 360 mm; it is beneficial to reduce the vortex critical height by 37.9%. The reduction of the distance between the coil and the molten steel also promotes the vortex suppression. The coil misalignment is beneficial to fully utilize the electromagnetic field; the critical height is reduced by 15%. The tangential velocity is changed when the nozzle diameter and eccentricity are optimized, and the vortex suppression will be amplified by using the electromagnetic field. This study provides the theoretical guidance for the optimizing design of the vortex suppression utilizing the static electromagnetic field.

On the adapting ability of living organisms to stationary and non-stationary electromagnetic fields

The adapting ability of living organisms is the key to survival of the species, and its scope is defined by homeostasis, meaning the tendency of any living system to maintain its biologic parameters. Heat shock proteins are part of a homeostasis system in charge with the regulation of damaged proteins caused by the action of several types of stressors. Among all types of stressors, the electromagnetic radiation has not yet been investigated in terms of heat shock protein response. Recent investigations regarding in vivo experiments using electromagnetic exposure from laboratory sources and commercial mobile phones indicate that the biologic response is more intense when using real life sources. This paper proposes a model for heat shock proteins expression as response to electromagnetic radiation exposure, based on a Hill controller.

Controlling Electronic Energy Transfer: A Systematic Framework of Theory

The transport of electronic excitation energy (EET) between ions, atoms, molecules or chromophores is an important process that occurs in a wide range of physical systems. The tantalising prospect of effective experimental control over such transfer is, in principle, amenable to a variety of different kinds of approach. Several of the most promising, which are analysed and compared in this paper, involve the influence of externally applied static electric or electromagnetic fields, or the exploitation of local media effects. A quantum electrodynamical framework is used as a common basis to describe the corresponding mechanisms, illustrated by specially adapted Feynman diagrams. It becomes evident that energy transfer between polar species engages an additional pairwise interaction beyond the EET coupling. Such an effect may also play an important role in interatomic Coulombic decay (ICD), a process that has recently attracted fresh interest. The control of ICD, in which the photoionisation of two nearby atoms via energy transfer, is determined to have analogous characteristics to conventional forms of EET.

Static and Electromagnetic Fields Differently Affect Proliferation and Cell Death Through Acid Enhancement of ROS Generation in Mesenchymal Stem Cells.

Magnetic fields remotely influence cellular homeostasis as a physical agent through the changes in cell physicochemical reactions. Magnetic fields affect cell fate, which may provide an important and interesting challenge in stem cell behaviors. Here, we investigated the effects of the static magnetic field (SMF, 20 mT) and electromagnetic field (EMF, 20 mT-50 Hz) on reactive oxygen species (ROS) production and the acidic pH conditions as stimuli to change cell cycle progression and cell death in mesenchymal stem cells. Results show that SMF, EMF, and their simultaneous (SMF+EMF) administration increase ROS and expression of nuclear factor erythroid 2-related factor 2 (Nrf2), superoxide dismutase 2 (SOD2), and glutathione-S-transferase (GST) as an antioxidant defense system. Besides, intracellular pH (pHi) decreases in presence of either EMF or SMF+EMF, but not SMF. Decreased ROS content using ascorbic acid in these treatments leads to increased pH compared to the magnetic field treatments alone. Furthermore, each magnetic field has different effects on the cellular process of stem cells, including cell cycle, apoptosis and necrosis. Moreover, treatment by SMF enhances the cell viability after 24 h, while EMF or SMF+EMF decreases it. These observations indicate that fluctuations of ROS generation and acid enhancement during SMF and EMF treatments may reveal their beneficial and adverse effects on the molecular and cellular mechanisms involved in the growth, death, and differentiation of stem cells.

Do magnetic fields related to submarine power cables affect the functioning of a common bivalve?

The aim of the study was to determine the effect of static magnetic field (SMF) and electromagnetic field (EMF), of values usually recorded near submarine cables, on the bioenergetics, oxidative stress, and neurotoxicity in the cockle Cerastoderma glaucum. Bivalves maintained a positive energy balance, but the filtration rate and energy available for individual production were significantly lower in SMF-exposed animals compared to the control treatment. No changes in the respiration were noted but ammonia excretion rate was significantly lower after exposure to EMF. Changes in the activities of antioxidant enzymes and the lipid peroxidation were not observed however, exposure to both fields resulted in increased protein carbonylation. After exposure to EMF a significant inhibition of acetylcholinesterase activity was observed. As the present study for the first time revealed the oxidative damage and neurotoxicity in marine invertebrate after exposure to artificial magnetic fields, the need for further research is highlighted.

Research on New Drilling Downlink Communication Based on Anisotropic Magnetoresistive Technology

With the continuous improvement of automatization of underground oil and gas resources exploitation, more and more instructions are required for the control technology while drilling in complex processes. The conventional downlink communication technology has shortcomings, such as data transmission lag and high bit error rate, which cannot meet the actual needs. Therefore, developing a new high-speed and low bit error rate (BER) downlink communication technology is very important. In this study, a new type of downlink communication system based on the electric current field is designed. Firstly, based on the theory of electromagnetic field and electromagnetic wave, the current distribution model of the drill string is established. Then, the magnetic field distribution model of the drill string is deduced according to the research on the static electromagnetic field and boundary problems. Finally, the ground simulation experiment platform of the downlink communication system is built and tested. The experimental results show that the BER is only 1.02% when the data transmission rate is 1 kbps. To further reduce the BER of the system, the influence factors of information transmission such as different transmitting voltage, inter-electrode distances, and working temperature are tested and analyzed, respectively, which provides ideas for optimizing the technology of downlink information communication while drilling.

The Effects of Anthropogenic Electromagnetic Fields (EMF) on the Early Development of Two Commercially Important Crustaceans, European Lobster, Homarus gammarus (L.) and Edible Crab, Cancer pagurus (L.)

Proposed offshore windfarm sites could overlap with the brooding and spawning habitats of commercially important crustacea, including European lobster, Homarus gammarus and Edible crab, Cancer pagurus. Concerns have been raised on the biological effects of Electromagnetic Fields (EMFs) emitted from subsea power cables on the early life history of these species. In this study, ovigerous female H. gammarus and C. pagurus were exposed to static (Direct Current, DC) EMFs (2.8 mT) throughout embryonic development. Embryonic and larval parameters, deformities, and vertical swimming speed of freshly hatched stage I lobster and zoea I crab larvae were assessed. EMF did not alter embryonic development time, larval release time, or vertical swimming speed for either species. Chronic exposure to 2.8 mT EMF throughout embryonic development resulted in significant differences in stage-specific egg volume and resulted in stage I lobster and zoea I crab larvae exhibiting decreased carapace height, total length, and maximum eye diameter. An increased occurrence of larval deformities was observed in addition to reduced swimming test success rate amongst lobster larvae. These traits may ultimately affect larval mortality, recruitment and dispersal. This study increases our understanding on the effects of anthropogenic, static EMFs on crustacean developmental biology and suggests that EMF emissions from subsea power cables could have a measurable impact on the early life history and consequently the population dynamics of H. gammarus and C. pagurus.