Electromagnetic Field Radiation Research Articles

Exploring the Effects of 2.45 GHz Electromagnetic Field Radiation in the Etiology of Endothelial Injury

The present study has been designed to investigate whether non-ionizing electromagnetic radiation (EMR) in the 2.45 gigahertz (GHz) band has deleterious effects on vascular endothelium. Twenty-four male Wistar-Albino rats were randomly divided into three groups (n=8 in each group) sham, study (EMR,1 h/day for 30 days), and control. Serum IL-18, IL-1?, TAS, TOS, and OSI levels were similar in each group. In aortic and carotid tissues; TAS, TOS, and OSI levels were found similar in each group whereas IL-18 and IL-1? levels were found elevated in the study group (p= 0.235, p= 0.023 in aorta; p= 0.048, p= 0.039 in carotid respectively). On the histopathological examination of the aortic tissue, significant endothelial and subendothelial damage was found in the study group. As a result of our findings, we have concluded that long-term exposure to EMR in the 2.45 GHz band may cause endothelial injury.

CONSIDERATION OF MULTIPATH IN MODELING THE FIELD OF SECONDARY ELECTROMAGNETIC RADIATION ON INFORMATIZATION OBJECTS

The paper considers the features of the formation of the resulting field of spurious electromagnetic radiation at informatization objects, taking into account the multipath propagation of radio waves, evaluates the achievable error values for determining the attenuation coefficient using known methods for determining the attenuation of the field of spurious electromagnetic radiation based on a deterministic model of radio wave propagation inside the building. The need for a significant refinement of the method for determining the attenuation coefficient is shown, since, in a known form, it is suitable only for measurements in free space and gives very significant errors in urban conditions and inside buildings, or the use of adaptive reception methods when receiving signals (for example, diversity reception), which allows to significantly reduce the level of interference dips in the resulting electromotive force.

Entanglement Entropy Analysis in Dicke's Model Quantum System

Entanglement is a property of interacting particles in a quantum system. The measure of the interaction can be known by looking for the entanglement entropy value in the system. The quantum system used in this study is the Dicke model quantum system which consists of a single-mode electromagnetic radiation field and a two-level N-atom. This study aims to determine the influence of the coupling constant on entanglement entropy and system dynamics. Simulation of system dynamics is carried out with the Quantum Toolbox in Python (QuTiP) module. The simulation results show that the coupling constant has a significant effect on the entanglement entropy value. The greater the value of the coupling constant used, the entanglement entropy value increases. In addition, there is a maximum entanglement entropy value for N greater than one. The coupling constant also affects the dynamics of the system, that is, the greater the value of the coupling constant, the more quantum states can be accessed by atoms.

The Effect of 2.45 GHz Electromagnetic Fields on Fear Memory Extinction in Male Rats.

Introduction: Fear memories are influenced by psychological and environmental variables. We evaluated the effect of 2.45 GHz microwave radiation on rats' fear learning and memory ability to determine the potential risks. The present study aimed to assess the impacts of corticosterone (CORT) levels on the consolidation and reconsolidation of fear conditioning memories. Methods: The rats were evaluated in contextual fear conditioning using foot shocks in both short-term (7 days) exposure and long-term (30 days) exposure. Young male Wistar rats were continually exposed to radio frequency electromagnetic field radiation for 5-6 weeks (1 h/day) with a frequency, power density, and pulse width of 2.45 GHz, 6.0 mW/cm2, and 2 ms, respectively. Several animals housed in identical conditions without exposure to radiation were monitored. Results: Based on the results, a significant increase and decrease in body weight and percentage of the freezing time were observed after the short-term group respectively. However, in the long term, we observed no significant difference in body weight, and the freezing time decreased substantially. Conclusion: As CORT levels were analyzed, long-term radiation might increase stress, which was associated with significant weight loss in rats.

Photons generated by gravitational waves in the near-zone of a neutron star

When a gravitational wave or a graviton travels through an electric or magnetic background, it could convert into a photon with some probability. In this paper, a dipole magnetic field is considered as this kind of background in both the Minkowski spacetime and the curved spacetime in the near-zone of a neutron star. In the former case, we find that the graviton traveling vertically rather than parallel to the background magnetic field could be more effectively converted into an electromagnetic radiation field. In the latter case, we focus on the situation, in which the graviton travels along the radial direction near a neutron star. The radius of a neutron star is about ten kilometers, so the gravitational wave with long wavelength or low frequency may bypass neutron stars by diffraction. For high frequency gravitational wave, the conversion probability is proportional to the distance square as that in the static electric or magnetic background case. The smaller the inclination angle between the dipole field and the neutron star north pole is, the larger magnetic amplitude will be. The term that described curved spacetime will slightly enhance this kind of probability. We estimate that this value is about the order of ∼10−14−10−10. Therefore, it is expectable that this kind of conversion process may have a potential to open a window for observing high frequency gravitational waves.

Investigating the Effects of 2850 MHz Electromagnetic Field Radiations on the Growth, Germination and Antioxidative Defense System of Chickpea (Cicer arietinum L.) Seedlings

Investigating the Effects of 2850 MHz Electromagnetic Field Radiations on the Growth, Germination and Antioxidative Defense System of Chickpea (Cicer arietinum L.) Seedlings

The effects of long-term prenatal exposure to 900, 1800, and 2100MHz electromagnetic field radiation on myocardial tissue of rats.

It is well-known that wireless communication technologies facilitate human life. However, the harmful effects of electromagnetic field (EMF) radiation on the human body should not be ignored. In the present study, we evaluated the effects of long-term, prenatal exposure to EMF radiation on the myocardium of rats at varying durations. Overall, 18 pregnant Sprague-Dawley rats were assigned into six groups (n = 3 in each group). In all groups other than the control group, three pregnant rats were exposed to EMF radiation (900, 1800 and 2100MHz) for 6, 12 and 24h over 20 days. After delivery, the newborn male pups were identified and six newborn male pups from each group were randomly selected. Then, histopathological and biochemical analysis of myocardial samples were performed. When 24-h/day prenatal exposures to 900, 1800, 2100MHz EMF radiation were evaluated, myocardial damage was greater in the 2100MHz EMF-24h group than the other groups. In addition, when malondialdehyde (MDA) and glutathione (GSH) levels associated with reactive oxidative species (ROS) were evaluated, the MDA level was higher in the 2100MHz EMF-24h group compared with the other groups. The GSH level was also lower in the 2100MHz EMF-24h group. When the 6, 12 and 24h/day prenatal exposures to 1800MHz EMF radiation were evaluated, myocardial damage was greater in 1800MHz EMF-24h group than the remaining groups (p < 0.0001). Also, MDA level was greater in the 1800MHz EMF-24h group compared with the other groups while the GSH level was lower in this group. It was shown that myocardial tissue was affected more by long-term exposure to EMF radiation at high frequencies. The data raise concerns that the harmful effects of non-ionizing radiation exposure on cardiac tissue will increase with 5G technology.

Апоптоз лимфоцитов при воздействии комбинации физических факторов

The article presents the comparative study results of the bioeffects of 30-minute exposure session to electromagnetic radiation with 1000 MHz frequency and 10 mW/cm2 EFD; of 30-minute exposure session to low-frequency pulsed magnetic field with 4 mT magnetic induction, as well as their combination, on rat’s lymphocytes apoptosis level in vivo. The apoptosis level was assessed morphologically with fluorescent microscope after 24-hours of cell suspension cultivation at immunological plates at 37 0C in nutrient medium without loading. The percentage of cells with morphological signs of apoptosis (margination, condensation and fragmentation of chromatin in nucleus) was quantitatively determined. It was found that electromagnetic irradiation had no significant impact on apoptosis level, but magnetic field action resulted in reducing the apoptosis cells number by 16% (p≤0,01) compared to the control group. The combination of electromagnetic radiation and low intensity magnetic field increased the apoptotic cells number by 28% (p ≤0.01) compared to the control. Thus, the mediated effect of electromagnetic radiation on blood cells genome leads to disruption of its normal functioning. It has been shown that low-frequency magnetic field can influence on intracellular processes in different directions; in combination with electromagnetic radiation it can intensify pathological reactions, and thus launching the apoptosis massive program.

Comparative Analysis of Electric Field Strength, Magnetic Field Strength and Power Density around the Cell Phone Towers of Varying Characteristics with a Proposed Classification Facilitating Research on Human Population.

The continuous exposure of electromagnetic field (EMF) radiation from cell phone towers may possibly have an influence on public health. Each cell phone tower is unique in terms of number of antennas and its associated attributes; thus, the radiation exposure varies from one tower to another. Hence, a standardized method for quantifying the exposure is beneficial while studying the effects of radiation on the human population residing around the cell phone towers. A mere collection of data or human samples without understanding the cell phone tower differences may show study results such as an increase or decrease in biological parameters. Those changes may not be due to the effects of EMF radiation from cell phone towers but could be due to any other cause. Therefore, a comparative study was designed with the aim of quantifying and comparing the electric field strength (EF), magnetic field strength (MF) and power density (PD) on four sides of cell phone towers with varying numbers of antennas at 50 m and 100 m. Further, an attempt was made to develop a PD-based classification for facilitating research involving human biological samples. Through convenience sampling, sixteen cell phone towers were selected. With the use of coordinates, the geographic mapping of selected towers was performed to measure the distance between the towers. Based on the number of antennas, the cell phone towers were categorized into four groups which are described as group I with 1-5 antennas, group II comprising of 6-10 antennas, group III consisting of 11-15 antennas and group IV comprised of towers clustered with more than 15 antennas. The study parameters, namely the EF, MF and PD, were recorded on all four sides of the cell phone towers at 50 m and 100 m. One-way ANOVA was performed to compare the study parameters among study groups and different sides using the Statistical Package for the Social Sciences (SPSS) version 25.0. The mean MF in Group IV was 2221.288 ± 884.885 μA/m and 1616.913 ± 745.039 μA/m at 50 m and 100 m respectively. The mean PD in Group IV at 50 m was 0.129 ± 0.094 μW/cm2 and 0.072 ± 0.061 μW/cm2 at 100 m. There was a statistically significant (p &lt; 0.05) increase in the MF and PD at 50 m compared to 100 m among cell phone tower clusters with more than 15 antennas (Group IV). On the other hand, a non-significant increase in EF was observed at 50 m compared to 100 m in Group II and IV. The EF, MF and PD on all four sides around cell phone towers are not consistent with distance at 50 m and 100 m due to variation in the number of antennas. Accordingly, a PD-based classification was developed as low, medium and high for conducting research involving any biological sample based on quantile. The low PD corresponds to 0.001-0.029, medium to 0.03-0.099 and high to 0.1-0.355 (μW/cm2). The PD-based classification is a preferred method over the sole criteria of distance for conducting human research as it measures the true effects of EMF radiation from the cell phone towers.

Optical Force of Bessel Pincer Light-Sheets Beam on a Dielectric Sphere of Arbitrary Size.

In the framework of Generalized Lorenz-Mie theory (GLMT), based on the expansion results of electromagnetic field radiation components of Bessel pincer light sheets beam acting on dielectric particles of arbitrary size, the expression of radiation force components in a Cartesian coordinate system is obtained by using the Maxwell stress tensor method. On the one hand, the effects of the refractive index and the equivalent radius of spherical particles on the distribution of radiation force are discussed; On the other hand, the influence of beam scaling parameter and beam order of Bessel pincer light sheets beam on the distribution of radiation force are investigated. The results indicate that the changes of particle's refractive index and effective radius only affect the distribution of radiation force. However, the beam scaling parameter and beam order of Bessel pincer light sheets beam have a very sharp impact on the convergence position, distribution range and bending degree far away from the wave source of the radiation force. Single-beam optical tweezers using the self-focusing and self-bending Bessel pincer light-sheets beam are crucial for applications such as single molecule biophysics, optical manipulation and particle separation/clearing.

Detecting chiral asymmetry in the interstellar medium using propylene oxide

Context.Life is distinctly homochiral. The origins of this homochirality are under active debate. Recently, propylene oxide has been detected in the gas-phase interstellar medium (ISM). The enantiomeric composition of ISM propylene oxide may be probed through circular polarization measurements, but accurate estimates of the circular dichroism properties of the microwave transitions of propylene oxide are not available.Aims.Our aim is to develop a model of the circular dichroic activity in torsion–rotation transitions of closed-shell chiral molecules such as propylene oxide. With this model we can estimate the viability, and optimize the observation strategies, of enantiomeric excess detection in ISM propylene oxide.Methods.Circular dichroism in spectral lines manifests through the simultaneous interaction of an electromagnetic radiation field with the molecular electric dipole moment and magnetic dipole moment. We developed techniques to quantify electric dipole and magnetic dipole moments of torsion–rotation transitions by expanding on earlier modeling of the electric and magnetic dipole properties of single torsion–rotation levels. To model the circular dichroism properties of propylene oxide, we used these techniques in combination with ab initio quantum chemical calculations.Results.The expressions for the dichroic activity of the microwave transitions of torsionally active molecules are derived. We find that the torsional motion of molecules exhibiting internal rotation contributes significantly to the total magnetic moment. We present estimates for the dichroic activity of the torsion–rotation transitions of propylene oxide. We predict that the circular polarization fractions of emission lines of enantiopure propylene oxide relevant to astronomical detections are on the order of 10−6.Conclusions.Due to the low predicted circular polarization fractions, we conclude that enantiomeric characterization of propylene oxide in the gas phase of the ISM is impossible with the current astronomical observation techniques. We suggest that only chiral radical species may be viably employed for purposes of enantiomeric excess detection. We estimate that laboratory experiments may be successful in detecting the enantiomeric composition of a mixture of propylene oxide through microwave dichroism spectroscopy.

Research on the Induced Electrostatic Discharge of Solar Arrays under the Action of ESD EMP

In this paper, the electrostatic discharge of solar arrays in spacecraft energy systems is taken as the research object. The influence and internal mechanism of external electromagnetic radiation on electrostatic discharge is studied. Meanwhile, the charging and discharging test platform of spacecraft solar arrays under a strong field is first established. Then, the influence of irradiation field strength, electron beam energy and beam density on electrostatic discharge of solar arrays is analyzed and summarized. The results show that during the irradiation process of solar arrays using a high-energy electron beam under vacuum conditions, the higher the electron beam energy and the beam current density, the higher the discharge frequency of the solar array. When the intensity of the external electromagnetic radiation field increases, the discharge frequency also increases. Under the action of external radiation field with the same peak field strength, the larger the gap, the smaller the discharge frequency. With the increase in the field strength, the potential difference of each part of the solar array becomes smaller, and the peak of the discharge current decreases. The research results can provide technical reference for electrostatic protection of spacecraft solar arrays.

Massive MIMO With Radio Stripes for Indoor Wireless Energy Transfer

Radio frequency wireless energy transfer (WET) is a promising solution for powering autonomous Internet of Things (IoT) deployments. In this work, we leverage energy beamforming for powering multiple user equipments (UEs) with stringent energy harvesting (EH) demands in an indoor distributed massive multiple-input multiple-output system. Based on semi-definite programming, successive convex approximation (SCA), and maximum ratio transmission (MRT) techniques, we derive optimal and sub-optimal precoders aimed at minimizing the radio stripes' transmit power while exploiting information of the power transfer efficiency of the EH circuits at the UEs. Moreover, we propose an analytical framework to assess and control the electromagnetic field (EMF) radiation exposure in the considered indoor scenario. Numerical results show that i) the EMF radiation exposure can be more easily controlled at higher frequencies at the cost of a higher transmit power consumption, ii) training is not a very critical factor for the considered indoor system, iii) MRT/SCA-based precoders are particularly appealing when serving a small number of UEs, thus, especially suitable for implementation in a time domain multiple access (TDMA) scheduling framework, and iv) TDMA is more efficient than spatial domain multiple access (SDMA) when serving a relatively small number of UEs. Results suggest that additional boosting performance strategies are needed to increase the overall system efficiency, thus making the technology viable in practice.

The influence of the patch antennas emissions on the human head

The influences of the antenna’s emissions on the human body are to be investigated because in our days, as a simple example, the mobile phone is permanently in use, on day or night. The long-time human exposure at the electromagnetic field radiations is obvious and there exist the possibility that these can affect the human health. The influences of the circular patch antenna’s emissions on the human head are analyzed at high frequency in this paper. First the patch antenna is modelled and simulated to extract its specific parameters and to represent the emitted electric and magnetic field around it. Next the human head is considered near to the patch antenna in position that imitates the mobile phone at ear and the electric field, the magnetic field, and the specific absorption rate (SAR) are represented to determine the antenna’s emissions at its operating frequency. So, the main aim of the paper is the high frequency analyzes of the circular patch antennas to investigate the influence of their emissions on the human head. The results obtained are compared and reported to the standards and legislation in force on human occupational exposure, to verify that the limits are met.

Electromagnetic Radiation Mechanism Analysis and Field Strength Prediction of an Elementary Digital Inverter with Cables

In this paper, common mode (CM) and differential mode (DM) far-field radiation models of a typical digital inverter with cables are built up to predict electromagnetic field strength and analyze field characteristics. The CM current model and its analyses are based on the imbalance difference method. It is found out that the voltage between the drain and the source electrodes of upper transistor is the key equivalent source of electromagnetic interference (EMI). Far-field radiation strength of the digital inverter in free space is predicted by using the asymmetrical antenna radiation method and current loop radiation method. The accuracy of these methods is verified by the CST electromagnetic simulation results in the frequency range from 1 MHz to 400 MHz. Furthermore, the radiation models are improved by using the mirror method, which enables to include the reflection effect of the metal ground plane at the electromagnetic compatibility (EMC) test site. Both the results of measurements in a semi-anechoic chamber and the simulation results confirm the proposed electromagnetic radiation prediction method.

Maternal stress induced anxiety-like behavior exacerbated by electromagnetic fields radiation in female rats offspring.

There is a disagreement on whether extremely low frequency electromagnetic fields (ELF-EMF) have a beneficial or harmful effect on anxiety-like behavior. Prenatal stress induces frequent disturbances in offspring physiology such as anxiety-like behavior extending to adulthood. This study was designed to evaluate the effects of prenatal stress and ELF-EMF exposure before and during pregnancy on anxiety-like behavior and some anxiety-related pathways in the hippocampus of female rat offspring. A total of 24 female rats 40 days of age were distributed into four groups of 6 rats each: control, Stress (rats whose mothers underwent chronic stress), EMF (rats whose mothers were exposed to electromagnetic fields) and EMF/S (rats whose mothers were simultaneously exposed to chronic stress and ELF-EMF). The rats were given elevated plus-maze and open field tests and then their brains were dissected and their hippocampus were subjected to analysis. ELISA was used to measure 24(S)-hydroxy cholesterol, corticosterone, and serotonin levels. Cryptochrome2, steroidogenic acute regulatory protein, 3B-Hydroxy steroid dehydrogenase, N-methyl-D-aspartate receptor 2(NMDAr2) and phosphorylated N-methyl-D-aspartate receptor 2(PNMDAr2) were assayed by immunoblotting. Anxiety-like behavior increased in all treatment groups at the same time EMF increased anxiety induced by maternal stress in the EMF/S group. The stress group showed decreased serotonin and increased corticosterone levels. ELF-EMF elevated the PNMDAr2/NMDAr2 ratio and 24(S)-hydroxy cholesterol compared to the control group but did not change corticosterone. EMF did not restore changes induced by stress in behavioral and molecular tests. The results of the current study, clarified that ELF-EMF can induce anxiety-like behavior which may be attributed to an increase in the PNMDAr2/NMDAr2 ratio and 24(S)-OHC in the hippocampus, and prenatal stress may contribute to anxiety via a decrease in serotonin and an increase in corticosterone in the hippocampus. We also found that anxiety-like behavior induced by maternal stress exposure, is exacerbated by electromagnetic fields radiation.

Channel Model and Performance Analysis for MIMO Systems with Single Leaky Coaxial Cable in Tunnel Scenarios.

Due to the limited space in the tunnel environment, multiple-input multiple-output (MIMO) systems with double-port fed leaky coaxial cables (LCXs) can not only reduce the number of LCXs, but also improve the channel capacity. Based on the geometry based on single bonce (GBSB) and electromagnetic field radiation theory of LCX, a MIMO channel model with double–port fed LCX in a tunnel scenario is proposed in this paper. The channel impulse response (CIR) is derived, and verified with measurement results in terms of channel capacity. The distribution of channel capacity of single double-port fed LCX under different LCX lengths in the tunnel scenarios has also been analyzed in this work, and the distribution of channel capacity for the LCX–MIMO system with long LCX is predicted. The results show that the single double-port fed LCX–MIMO system outperforms the dipole antenna MIMO system with respect to channel capacity in the considered tunnel scenarios.

Empirical studies on the effect of electromagnetic radiation from multiple sources in Dhaka

&lt;span&gt;Just after the invention of electricity by Michael Faraday, there has been a revolution in the communication technology, which lead to the invention of radio, television, radar, satellite, and mobile. While these machines transformed our life high quality, safer and simpler, they have been associated with alarming probable health hazards owing to their electromagnetic radiation (EMR) emission. Couple of cases it has been reported by personals regarding various health related issues relating to exposure on electromagnetic field (EMF) and EMR. Although couple of persons showed light symptoms and respond by avoiding the electrical field (EF) and EMR fields as much as possible, some others are so much affected that they have changed their entire lifestyle. In this paper, empirical survey study has been carried out in the laboratories of Daffodil International University (DIU) main and permanent campus. It was found that some of the instrument had higher EMFs. The findings from this survey may be helpful for the students to take precautionary measurement who work for long duration in the various laboratories for their practical classes and for the users of the domestic appliances as well as office equipment and industrial instruments.&lt;/span&gt;

Содержание фенольных соединений в лишайниках в зонах тектонических разломов

The paper studies the influence of geoecological factors on the content of phenolic compounds (PCs) in lichens of the genus Cladonia in the Velsko-Ustyansky and Kholmogorsky tectonic knots (TKs). Lichens were sampled from the test plots (TPs) laid out in the center of the knots and outside the knots (control). The geochemical situation, soil-climatic and environmental conditions in the zone of TKs influence the lichens chemical composition. It is found that the ash content of lichens growing in the center of the TK is 1.8–2.3 times higher than in the control, which indicates a significant accumulation of lithogenic elements in the lichen thallus in the tectonic fault zone. Lichens are exposed to multifactorial adverse effects (increased radiation background and heat flux, electromagnetic radiation, electric and magnetic fields, etc.) in the territory of TKs. This provokes excessive generation of active oxygen radicals and contributes to the rearrangement of lichen metabolism, changing the dynamics of accumulation of PCs and their biosynthesis. The content of the water-insoluble fraction of PCs in lichens was found to increase from the control point to the center of the TK, while the relative share of the water-soluble fraction of PCs in the total composition decreases. This is probably due to an increase in oxidative processes and a decrease in reductive processes in lichens under adverse conditions. The paper shows that the biosynthesis of PCs in lichens is most active in the spring-summer (April and July) vegetation period. The impact of geoecological factors enhances the biosynthesis of secondary metabolites of phenolic nature in lichens in the conditions of the TKs: usnic acid (UA) and atranorin. The content of UA in the composition of the water-insoluble fraction of PCs in lichens growing in the center of the TK is 1.5–1.7 times higher during the spring-summer vegetation period than in lichens growing outside the TK. The quantitative distribution of the water-insoluble fraction of PCs depends on the lichen thallus part and has a gradient character. Their content in the upper growing parts of lichens growing in the center of the TK and in the control is 2 and 1.7 times higher than in the old zones, respectively. Thus, PCs in lichens are active metabolites and their content in thallus can serve as a biomarker of the state of the environment.

The Feynman paradox and hidden momentum

Though it is generally accepted that electromagnetic radiation fields possess energy and linear and angular momentum, the adscription of these properties to static and quasi-static fields rises some doubts. Some authors consider that in electrostatics the concept of field is superfluous, or that action-at-a-distance and field are equivalent views. However, the interpretation of Poynting’s vector divided by c 2 as a momentum density is consistent and necessary for the conservation laws to hold, even in static conditions. The Feynman paradox exhibits the necessity of assigning linear and angular momentum to static and quasi-static fields, showing in this way that the points of view of action-at-a-distance and field are not equivalent. In the present work we do not intend to present a revision of the literature on this subject, but to show that the concept of hidden momentum is useful to solve the paradox, and we show that it is part of a momentum balance equation derived directly from the macroscopic Maxwell equations. Another consequence of this balance equation is that, in static conditions, the momentum associated to Poynting’s vector equals the hidden momentum and cancels it. Graduate students and researchers interested in conceptual problems of electromagnetism will find a firm foundation of the concept of hidden momentum and an alternative view of the paradox.