Features of generation and propagation of the extremely low frequency waves excited in the ionosphere under the powerful HF radioemission influence

The experimental results of the extremely low frequency emission characteristics excited in the outer ionosphere under the ionospheric plasma heating by high-latitude EISCAT facility are presented. The experiments have been conducted in the period of 20062010 yr. using two main schemes of extremely low frequency generation including the impact of the heating facility amplitude modulated emission and two unmodulated pump waves with the frequency detuning. In-situ measurements of the plasma wave disturbances were performed at the outer ionosphere heights using on-board equipment of DEMETER microsatellite. In work the spatial, amplitude and spectral characteristics of the generated extremely low frequency emissions are determined. It is shown that the characteristic size of the extremely low frequency emission is about 400600 km along the trajectory of the DEMETER microsatellite. The registration area spatial position is determined by both the applied generation scheme and the background plasma density distribution. The extremely low frequency emission electric field strength at the Earths outer ionosphere heights is 50330 V/m.

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Comparing the Impact of Long-Term Exposure to Extremely Low-Frequency Electromagnetic Fields With Diverse Values on Anxiety, Memory, Learning, And Β-Amyloid Deposition In Adult Rats

Basic and Clinical Neuroscience Journal ◽

10.32598/bcn.2021.1204.2 ◽

2021 ◽

pp. 1-24

Author(s):

Nafiseh Faraji ◽

◽

Iraj Salehi ◽

Akram Alizadeh ◽

Arash Pourgholaminejad ◽

...

Keyword(s):

Electromagnetic Fields ◽

Low Frequency ◽

Amyloid Deposition ◽

Control Group ◽

Adult Rats ◽

Male Adult ◽

Extremely Low Frequency ◽

Β Amyloid ◽

The Impact ◽

The Brain

Background: Extremely low-frequency electromagnetic fields (ELF-EMFs) have gathered significant consideration for their possible pathogenicity. However, their effects on nervous system functions were not fully clarified. In this study, our aim was to assay the effect of ELF-EMFs with different intensity on memory, anxiety, antioxidant activity, beta amyloid (Aβ) deposition and microglia population in rats. Materials and Methods: Fifty male adult rats were randomly separated into 5 groups; four groups exposed to a flux density of 1, 100, 500 and 2000 microtesla (µT), 50 Hertz (Hz) frequency for 1h/day for 2 months and one group as a control group. The control group were without ELF-EMF stimulation. After 8 weeks, passive avoidance and elevated plus maze (EPM) tests was performed to assess memory formation and anxiety-like behavior, respectively. Total free thiol groups and the index of lipid peroxidation were assessed. Also, for detection of β-Amyloid deposition and stained microglia in the brain, anti-β-amyloid and anti-Iba1 antibodies were used. Results: In the ELF-EMF exposure groups, the step-through latency was significantly greater in the retention test (100,500, and 2000 µT) than in the control group (P<0.05). Also, the percentage of the entries into the open arms in ELF-EMF exposure groups (especially 2000 µT) decreased than control group (P <0.05). No β-Amyloid depositions were detected in the hippocampus of different groups. An increase in microglia numbers in the 100, 500 and 2000 µT groups was observed in compare to the control and 1 µT group. Conclusion: Exposure to ELF-EMF had an anxiogenic effect on rats and promoted memory and also induced oxidative stress. No β-Amyloid depositions were detected in the brain. Also, positive effect of ELF-EMF was observed on population of microglia population in the brain.

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Real-Time Suppression Technology Research on Shaft-Rate Electric Field

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.602-605.2649 ◽

2014 ◽

Vol 602-605 ◽

pp. 2649-2653

Author(s):

Jun Zhong Sun ◽

Hai Long Jiang ◽

Zhen Sheng Xia ◽

Kuo Ting Wang

Keyword(s):

Electrical Properties ◽

Electric Field ◽

Real Time ◽

Low Frequency ◽

Equivalent Model ◽

Technology Research ◽

Close Loop System ◽

Extremely Low Frequency ◽

Frequency Electric Field ◽

The Impact

To reduce the impact of shaft-rate electric field (SRE) on the concealment of the ship, the SRE related ship electrical equivalent model is established, and the electrical properties are studied based on the analysis of the mechanism of SRE of the ship in this paper. The ship SRE real-time suppression is proposed based on the compensated negative potential and the real-time close-loop system for the ship SRE suppression is designed. The extremely low frequency electric field strength is reduced greatly, and the shaft-rate and its harmonics field are eliminated ultimately. Experimental results show that the ship SRE can be suppressed effectively by the system, and the concealment of the ship is enhanced.

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Improving the quality of sleep under distant effects of weak extremely low frequency electromagnetic fields measured by subjective indicators

SOCIALNO-ECOLOGICHESKIE TECHNOLOGII ◽

10.31862/2500-2965-2018-2-61-82 ◽

2018 ◽

pp. 61-82

Author(s):

I.S. Blokhin ◽

G.N. Arsen'ev ◽

V.B. Dorokhov

Keyword(s):

Circadian Rhythms ◽

Sleep Quality ◽

Sleep Latency ◽

Low Frequency ◽

Subjective Assessment ◽

Pulse Frequency ◽

Sleep Fragmentation ◽

Extremely Low Frequency ◽

The Impact

Periodic variations of natural weak extremely low frequency electromagnetic field (ELF-EMF) along with illumination can serve for entrainment of circadian rhythms. It seems promising to use the non-pharmacological remote physiotherapy exposure to ELF-EMF for the correction of sleep disorders and the normalization of circadian rhythms of sleep. The aim of our study was to assess the impact of weak ELFMF on different characteristics of night sleep, estimated by subjective assessment of sleep quality. In our experiments, an ELF-EMF generator “Smart Sleep” formed rectangular current pulses supplied to the magnetic field emitter. The device has 7 modes of pulse frequency: 2, 4, 8, 16, 20, 32, 40 Hz. At a distance of 70–200 cm from the device field intensity was less than 0.2 µT, which is significantly less than the permissible hygienic standards. 20 healthy volunteers (both sexes, aged 20–30) took part in the study and self-assessed the night’s sleep: sleep quality, sleep latency, wellbeing on awakening, sleep fragmentation, quality of dreams, emotions in dreams, dreams’ memorability, awareness in dreams. The Kruskall-Wallis single-factor rank analysis was used. Significant improvements under ELF-EMF influence were found: p < 0,05 for the: wellbeing on awakening (4 Hz, 20 Hz), sleep fragmentation (8 Hz) and latency (20 Hz), the dream memorability (4 Hz), quality (2 Hz, 16 Hz), emotions (8 Hz) and awareness (20 Hz); p < 0,01 for the: sleep latency (32 Hz), the dream memorability (2 Hz), quality (4Hz) and emotions (2 Hz).

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Assessment of the effects of exposure to extremely low-frequency magnetic fields on MDCK epithelial cell lines under a controlled environment

Journal of Radiation Research ◽

10.1093/jrr/rrab001 ◽

2021 ◽

Author(s):

Gonzalo Domínguez ◽

Eladio Cardiel ◽

Elsa Sánchez ◽

Pablo-Rogelio Hernández

Keyword(s):

Magnetic Field ◽

Cell Migration ◽

Magnetic Fields ◽

Cell Lines ◽

Cell Monolayer ◽

Low Frequency ◽

Controlled Environment ◽

Cell Nuclei ◽

Extremely Low Frequency ◽

The Impact

Abstract To assess the effects of exposure to extremely low-frequency magnetic fields (ELF-MFs) on MDCK cell lines, experiments were performed in a chamber under controlled conditions (temperature, humidity and CO2). Therefore, the measured physicochemical and electrical changes in the cells are due solely to the magnetic field exposure and not to external factors. A developed sinusoidal magnetic field generator produced the ELF-MFs with a uniform magnetic field and adjustable intensity and frequency. Three experimental indicators were used: (i) transepithelial electrical impedance (TEEI); (ii) cell migration and proliferation; and (iii) expression of the proteins of the tight junctions, and changes in the area and shape of the cell nuclei. No significant effects on TEEI values were observed when 10 and 50 G 60 Hz magnetic fields were applied to confluent cell monolayers. There were no significant differences in migration and proliferation of the cell monolayer exposed to 60 Hz magnetic fields10 and 50 G , but a contact inhibition factor was observed. The expression of the CLDN-1 protein decreased by 90% compared with the control, while ZO-1 protein expression increased by 120%. No significant effects were observed in the area and shape of the cell nuclei. Experimentation in a controlled environment, under physiological conditions, ensures that the observed effects were strictly due to exposure to magnetic fields. Different exposure conditions are necessary to determine the impact on TEEI and cell migration–proliferation indicators.

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The impact of thermal gas in AGN jets on the low-frequency emission

Astronomy and Astrophysics ◽

10.1051/0004-6361:20040546 ◽

2004 ◽

Vol 425 (2) ◽

pp. 405-416 ◽

Cited By ~ 5

Author(s):

M. Siewert ◽

M. Pohl ◽

R. Schlickeiser

Keyword(s):

Low Frequency ◽

The Impact ◽

Frequency Emission

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The impact of extremely low frequency electromagnetic field (50Hz, 0.25 mT) on fitness components and wing traits of Drosophila subobscura

Genetika ◽

10.2298/gensr1503967p ◽

2015 ◽

Vol 47 (3) ◽

pp. 967-982 ◽

Cited By ~ 1

Author(s):

Aleksandra Patenkovic ◽

Tatjana Savic ◽

Bojan Kenig ◽

Zorana Kurbalija-Novicic ◽

Marko Andjelkovic

Keyword(s):

Biological Effects ◽

Low Frequency ◽

Drosophila Subobscura ◽

Directional Asymmetry ◽

Control Group ◽

Past Century ◽

Wing Size ◽

Fitness Components ◽

Extremely Low Frequency ◽

The Impact

Over the past century, man-made electromagnetic fields (EMF) have changed the natural environment, representing one of the most common and rapidly increasing environmental factors as technology advances. Numerous studies of biological effects of exposure to EMF have been performed on Drosophila during the last 30 years, showing contrasting results. In an attempt to determine whether EMF exposures might affect the development of Drosophila, the present study examines phenotypic variations through direction and range of changes in several fitness components and wing length and width, of Drosophila subobscura isofemale lines, affected by 50 Hz EMF. Embryonal and early post-embryonal stages were exposed to homogeneous sinusoidal 0.25 mT EMF of 50 Hz. The EMF exposure caused a significantly prolonged developmental time and significantly increased the wing size with the opposite direction of directional asymmetry compared to the control group. These results shows that even such a weak EMF has the potential to modulate, through developmental pathways, some of the fitness-related traits, wing size, and wing asymmetry in D. subobscura even after one generation of exposure, showing that extremely low frequency (ELF) EMFs have relevant consequences on development, adult morphology, and fitness.

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