Natural Geomagnetic Field Research Articles

Analysis of the Effects of Magnetic Field on the Haemogram Profile and Protein Content of Eri Silkworm, <i>Philosamia ricini</i>

The geomagnetic field is a naturally occurring physical force that operates to sustain life on earth. However, recent advances in technology, rapid urbanization and electromagnetic pollution have led to interferences in strength of the magnetic field, which has resulted in various health hazards in several life forms. This study was carried out to understand the effect of magnetic fields that are greater than the strength of the natural geomagnetic field in Philosamia ricini, commonly known as Eri silkworm. Qualitative and quantitative analysis of the haemogram profile as well as the total protein content, were considered for analysis. The 5th instar silkworm larvae were exposed to two magnetic fields of different strengths, namely 0.4493G and 0.8345G, and changes were recorded and compared with a control group. The results revealed decrease in the number of haemocytes and disruption of haemocytes that increased with increase in strength of magnetic field along. The total protein content of haemolymph also underwent changes with changes in the strength of the magnetic field. Such studies and future in-depth analysis of different biological parameters in organisms due to the changing geomagnetic field might be beneficial in understanding and maneuvering the effects of magnetic field on organisms.

Влияние магнитных полей на ацетилирование H3K9/14 в нейронах грибовидных тел медоносной пчелы

Living things have been evolving under certain parameters of the geomagnetic field. Many organisms are sensitive to electromagnetic fields and use them for spatial orientation and navigation during migration. The honeybee Apis mellifera L. is a convenient experimental model to study the biological effects of electromagnetic fields. The honeybees use the Earth’s magnetic field for orientation in space and mobilization for foraging. Recent decades have seen an emergence of numerous anthropogenic sources of electromagnetic radiation. They are likely to be stressors for bees and other insects. It is known the transcriptional activity changes as part of stress response, while histone acetylation is associated with transcription activation. The article reports the results of the study into H3K9/14 histone acetylation in the neurons (inner Kenyon cells) of mushroom body calyxes (structures responsible for learning and memory in insects) in the honeybee. It was shown that an increase in the natural geomagnetic field leads to a decrease in H3K9/14 histone acetylation. This indicates a decrease in transcriptional activity in mushroom bodies, which may affect cognitive and foraging activities of the honeybee.

Perception of static magnetic field by humans: a review

We review the scientific data available on the ability of humans to perceive static magnetic fields with intensities comparable to the intensity of the natural geomagnetic field. It is currently assumed that birds have at least two independent magnetoreceptory systems. Various authors have reported the existence of the sensory ability to perceive the Earth’s magnetic field and to use it for spatial orientation in different species of mammals. The question of whether this ability exists in humans has been raised repeatedly. During the past 40 years, serious scholarly titles have published the results of behavioral studies on humans’ ability to perform homing to their home range by magnetic cues, of the ability to point towards a certain magnetic compass direction, and claims of magnetic modulation of the ability to discriminate weak light flashes. Several research groups have tried to find out whether brain bioelectric activity responds to changes in the stationary magnetic field. Cortical activation following changes in the static magnetic field, which suggested transduction of the changes in the Earth’s magnetic field into neural responses, was found by analyzing event-related synchronization/desynchronization. However, no behavioral manifestation for the putative magnetoreception in humans is evident. All attempts to detect behavioral responses to magnetic field changes in humans have been less than convincing.

Effects of magnetic fields related to submarine power cables on the behaviour of larval rainbow trout (

The aim of this study was to determine the effects of artificial magnetic fields on the behaviour of rainbow trout (Oncorhynchus mykiss) larvae. Individuals (from the eyed egg stage) were exposed to a static magnetic field (SMF) of 10 mT or a low-frequency alternating (electromagnetic) field (EMF) of 1 mT, whereas larvae in the control treatment were reared under a natural geomagnetic field (GMF). After 40 days exposure, larvae were tested for 46 h for their attraction to or avoidance of magnetic fields. None of the groups of larvae avoided either the static or alternating field. By contrast, a mean of 54–60% of individuals was recorded in magnetic fields. Moreover, larvae exposed to SMF or EMF were more attracted to their respective magnetic field than individuals reared under a natural GMF. In addition, no stress response (i.e. a change in the oxygen consumption rate) was recorded for O. mykiss larvae exposed to magnetic fields. These results suggest, for the first time, that early life stages of rainbow trout can detect and are attracted to artificial magnetic fields of a magnitude recorded in the vicinity of submarine cables, with no visible signs of stress (i.e. increased oxygen consumption).

Studying the shielding of an electromagnetic field by a textile material containing ferromagnetic nanostructures

The technology has been proposed for manufacturing a textile material that contains ferromagnetic nanoparticles for shielding electromagnetic fields. It has been shown that the most effective method of sticking together between nano-particles and the fibers of the textile material is the application of magnetic liquid with nanoparticles on the material and its exposure in a heterogeneous permanent magnetic field. Under the condition of a magnetic field intensity of 450 A/m and the exposure to it for 12 hours, the implantation of the nanoparticles into the linen fabric becomes almost irreversible. The protective properties of the developed material have been investigated. When impregnated with a magnetic liquid in the amount of 45–50 g/m2 (a ferromagnetic particle content of 9 % by weight), the material's shielding coefficients for 1–3 layers amount to: for the electric field of industrial frequency 1.4÷4.8; for a magnetic field, 1.9÷8.1. Following the magnetic treatment, these indicators are 2.9÷8.6 and 2.3÷8.9, respectively. In order to remove technological components such as vacuum oil and oleic acid from the magnetic fluid, it would suffice to apply a synthetic detergent, which has been confirmed by experimentally.We have investigated the efficiency of the obtained result under actual industrial conditions. It was established that the decrease in the magnetic field intensity of industrial frequency and its inter-harmonics by a single layer of the impregnated material without magnetic treatment is 1.4, with a magnetic treatment ‒ 2. In this case, there is no significant decrease in the level of the natural geomagnetic field. We have modeled the distribution of a magnetic field in the human body for the case of manufacturing a protective suit from the developed material. Under the conditions of a warranted reduction in the magnetic field intensity by 2 times in critical places, an increase in the field level is observed in the cervical region due to the increase in the magnetic resistance in this region. This should be considered when designing the protective suit configuration

Estimation of self noise of geomagnetic and geoelectric field sensors using multichannel measurement method

Results of synchronous electric and magnetic fields measurements made by different types of sensors in the frequency range of 0.002–7000 Hz are covered. Different approaches to obtaining the evaluation of sensor noise are considered. The technique of quantitative estimation of level of natural noise of each sensor and characteristics of a natural field on the basis of two- and three-channel scheme of synchronous measurement is given. Comparison of experimental noise estimations with computational ones is given. It is shown that the magnetometer based on magnetomodulation transducer has an unacceptably high level of its self noise for using it in applications related to the measurement of natural geomagnetic field.

Potential effects of electrical energy transmission – the case study from the Polish Marine Areas (southern Baltic Sea)

Abstract The operation of offshore wind turbines and electricity transmission through submarine cables over long distances generate electromagnetic or static magnetic fields (depending on the technical solution) that may modify the natural geomagnetic field and cause induced electric and electromagnetic fields in the water. The present study synthesizes the current knowledge and speculates on the possible environmental impact of electrical energy transfer based on the example of the Polish Marine Areas (southern Baltic Sea). We review the possible effects of the electrical energy induction and transfer against the existing and planned wind turbine installations. Furthermore, we consider different cable design variants as a way of environmental impact mitigation. Possible impacts of induced magnetic fields on marine organisms and, consequently, on the ecosystem functioning are also addressed.

The Influence of Weak Geomagnetic Disturbances on the Rat Cardiovascular System under Natural and Shielded Geomagnetic Field Conditions

Abstract—This work was aimed at studying the effects of weak geomagnetic disturbances on systolic blood pressure, the R–R interval, the low-frequency and high-frequency components, and its ratio of heart rate variability spectrum under natural and shielded geomagnetic field conditions. All tests were performed with male Wistar rats placed in simulation and shielded chambers. In the simulation chamber, significant shifts in the parameters under study were observed on the days of geomagnetic disturbances: an increase in systolic blood pressure, as well as in the ratio of low- to high frequency components of the heart rate variability spectrum. In the shielded chamber, the parameters were not considerably different under quiet and disturbed geomagnetic field. In addition, in the stimulation chamber, the value of the mean daily barometric pressure was inversely correlated with systolic blood pressure; this relationship was significantly weakened under shielded geomagnetic field conditions. It was concluded that weak geomagnetic disturbances affect cardiovascular and autonomic nervous system functions. The authors hypothesize that the enhanced effect of a slight decrease in barometric pressure on systolic blood pressure in the natural geomagnetic field could be associated with the effect of geomagnetic activity on the mechanisms of blood oxygenation.

Эффективность сочетанного применения гистохрома и полудана в составе комплексной терапии у больных с кератоконъюнктивитами, подвергающихся действию аномального геомагнитного поля

The immuno-metabolic and clinical efficacy of combined application of histochrome and Poludanum was studied in the complex therapy of patients with bacterial keratoconjunctivitis residing in the area of Kursk magnetic anomaly with a high level of natural geomagnetic field. According to the indicators of aggregate impact on immuno-metabolic status and clinical manifestations of the disease the combination of standard therapy with intramuscular introduction of histochrome and instillation of Poludanum was considered more effective. The use of the complex therapy with histochrome and Poludanum caused 33.3% of the investigated immuno-metabolic blood parameters, 29.6% of mixed saliva indicators and 29.4% of lacrimal fluid indicators with no significant differences from the healthy values in the region (during the standard therapy, the percentage of normalized indicators in blood, saliva and lacrimal fluid made up 22.2%, 29.6% and 29.6%, respectively). After applying the complex therapy the expressed reduction in the level of discomfort made 5.5 points, in itching 2.55 points, in discharge- 3.9 points, in conjunctiva oedema - 3.55 points (after the standard treatment those indicators made up 4.3, 2.2, 2.95 and 2.85 GPA, respectively).

Exploratory behavior of juvenile roach Rutilus rutilus (L.) (Teleostei: Cyprinidae) in a maze after different magnetic impacts on embryos

We have investigated a sequence of visits to arms in a cross maze in juvenile (1-year-old) roach Rutilus rutilus (L.). Fish embryos of one group are raised under a natural geomagnetic field. The embryos of another group are exposed to the main phase of a simulated geomagnetic storm (changes in geomagnetic field up to 100 nT for each component). It turns out that the sequence of visits does not differ from random in both groups. Thus, the exploratory behavior in juvenile roach differs from other animal taxa investigated earlier. In the latter taxa a spontaneous alternation was observed: a tendency to visit the arm which was visited least recently.

Скрининговые исследования естественных геомагнитных полей в Средневолжском регионе

Скрининговые исследования естественных геомагнитных полей в Средневолжском регионе

Influence of magnetic field on zebrafish activity and orientation in a plus maze

We describe an impact of the geomagnetic field (GMF) and its modification on zebrafish's orientation and locomotor activity in a plus maze with four arms oriented to the north, east, south and west. Zebrafish's directional preferences were bimodal in GMF: they visited two arms oriented in opposed directions (east–west) most frequently. This bimodal preference remained stable for same individuals across experiments divided by several days. When the horizontal GMF component was turned 90° clockwise, the preference accordingly shifted by 90° to arms oriented to the north and south. Other modifications of GMF (reversal of both vertical and horizontal GMF components; reversal of vertical component only; and reversal of horizontal component only) did not exert any discernible effect on the orientation of zebrafish. The 90° turn of horizontal component also resulted in a significant increase of fish's locomotor activity in comparison with the natural GMF. This increase became even more pronounced when the horizontal component was repeatedly turned by 90° and back with 1min interval between turns. Our results show that GMF and its variations should be taken into account when interpreting zebrafish's directional preferences and locomotor activity in mazes and other experimental devices.

Bats respond to very weak magnetic fields.

How animals, including mammals, can respond to and utilize the direction and intensity of the Earth’s magnetic field for orientation and navigation is contentious. In this study, we experimentally tested whether the Chinese Noctule, Nyctalus plancyi (Vespertilionidae) can sense magnetic field strengths that were even lower than those of the present-day geomagnetic field. Such field strengths occurred during geomagnetic excursions or polarity reversals and thus may have played an important role in the evolution of a magnetic sense. We found that in a present-day local geomagnetic field, the bats showed a clear preference for positioning themselves at the magnetic north. As the field intensity decreased to only 1/5th of the natural intensity (i.e., 10 μT; the lowest field strength tested here), the bats still responded by positioning themselves at the magnetic north. When the field polarity was artificially reversed, the bats still preferred the new magnetic north, even at the lowest field strength tested (10 μT), despite the fact that the artificial field orientation was opposite to the natural geomagnetic field (P<0.05). Hence, N. plancyi is able to detect the direction of a magnetic field even at 1/5th of the present-day field strength. This high sensitivity to magnetic fields may explain how magnetic orientation could have evolved in bats even as the Earth’s magnetic field strength varied and the polarity reversed tens of times over the past fifty million years.

The influence of magnetic field on the spatial orientation in zebrafish Danio rerio (Hamilton) and roach Rutilus rutilus (L.)

Event Abstract Back to Event The influence of magnetic field on the spatial orientation in zebrafish Danio rerio (Hamilton) and roach Rutilus rutilus (L.) Elena A. Osipova1, Vera V. Pavlova1, Anastasia A. Batrakova2 and Viacheslav V. Krylov1* 1 I.D. Papanin Institute for Biology of Inland Waters Russian Academy of Sciences, Russia 2 P.G. Demidov Yaroslavl State University, Russia Known, that some teleostei can perceive the geomagnetic field (GMF). However, the information about magnetosensitivity in Cyprinidae fish from artificial and natural habitats is obscure. We have registered preferred directions in Danio rerio (Hamilton) from aquaria-cultivated line exposed to the natural GMF, 180 degrees reversal of horizontal GMF component, 180 degrees reversal of vertical GMF component, 180 degrees reversal of both vertical and horizontal GMF components and 90 degrees clockwise turn of horizontal GMF component. We also registered the preferred directions in Rutilus rutilus (L.) from Rybinsk reservoir exposed to the natural GMF and 90 degrees clockwise turn of horizontal GMF component. It was found that zebrafish prefer two opposite directions towards east and west in the natural GMF. When the horizontal component of GMF was turned 90 degrees clockwise D. rerio prefer two opposite directions towards north and south. The possible reason of bimodality in zebrafish’s preferred directions distributions is discussed. The only direction towards east-north-east observed in roach under the natural GMF. This direction coincided with the way from the place of capture to the streamflow part of Rybinsk reservoir. And it was changed by south-south-east direction when turned the horizontal component of GMF 90 degrees clockwise. The possible reason of the choosing directions by fish with GMF is discussed. Acknowledgements This work was supported by grant from the Russian Foundation for Basic Research (Project #14-04-31157-mol_a). Keywords: danio rerio, Rutilus rutilus, Preferred Direction, Orientation, geomagnetic field Conference: XV European Congress of Ichthyology, Porto, Portugal, 7 Sep - 11 Sep, 2015. Presentation Type: Poster Presentation Topic: Physiology, Behavior and Toxicology Citation: Osipova EA, Pavlova VV, Batrakova AA and Krylov VV (2015). The influence of magnetic field on the spatial orientation in zebrafish Danio rerio (Hamilton) and roach Rutilus rutilus (L.). Front. Mar. Sci. Conference Abstract: XV European Congress of Ichthyology. doi: 10.3389/conf.fmars.2015.03.00082 Copyright: The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers. They are made available through the Frontiers publishing platform as a service to conference organizers and presenters. The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated. Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed. For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions. Received: 10 Nov 2015; Published Online: 17 Nov 2015. * Correspondence: Dr. Viacheslav V Krylov, I.D. Papanin Institute for Biology of Inland Waters Russian Academy of Sciences, Borok, Yaroslavl oblast, 152742, Russia, krylovviacheslav@mail.ru Login Required This action requires you to be registered with Frontiers and logged in. To register or login click here. Abstract Info Abstract Supplemental Data The Authors in Frontiers Elena A Osipova Vera V Pavlova Anastasia A Batrakova Viacheslav V Krylov Google Elena A Osipova Vera V Pavlova Anastasia A Batrakova Viacheslav V Krylov Google Scholar Elena A Osipova Vera V Pavlova Anastasia A Batrakova Viacheslav V Krylov PubMed Elena A Osipova Vera V Pavlova Anastasia A Batrakova Viacheslav V Krylov Related Article in Frontiers Google Scholar PubMed Abstract Close Back to top Javascript is disabled. Please enable Javascript in your browser settings in order to see all the content on this page.

Reassessing laboratory results of low-frequency electromagnetic field exposure of cells in culture [telecommunications health and safety

A systematic measurement has shown that the background static and ELF magnetic fields in biological incubators can vary by orders of magnitude within a single incubator and between different incubators. Measured incubator fields varied from below levels that the IARC had classified as possibly carcinogenic to humans (0.3 μT to 0.4 μT) to as high as 240 μT, above the Earth or natural geomagnetic field range (23 μT to 65 μT). The significance is that studies of biological effects of ELF field exposure on cell cultures involved magnetic fields ranging from 0.1 μT to 50 μT. The inconsistency or variability of in vitro laboratory data prompted many to declare that there was no compelling evidence that biological effects are causally related to ELF magnetic-field exposure. Most in vitro investigations involving cell cultures in the laboratory were unaware of and therefore did not account for the large variations in background static and ELF magnetic fields in cell-culture incubators. Given the potential confounding of unspecified incubator fields, it seems only reasonable to reassess the data and reevaluate the validity of any conclusions to date, positive or negative. Are we back to square one? In some sense, it may be so: the reported background static and ELF magnetic-field variations in cell-culture incubators could be a game changer.

Age-Dependent Orientation to Magnetically-Simulated Geographic Displacements in Migratory Australian Silvereyes (Zosterops l. lateralis)

Geographic relocations of migratory passerines have shown that adults can compensate for physical displacements; juveniles on their first migration, however, use an innate clock-and-compass strategy and are unable to compensate for displacement. We examined the effects of changes in magnetic inclination and intensity on orientation of adult and juvenile Australian Silvereyes (Zosterops l. lateralis) to learn if geomagnetic cues are used by a migratory passerine for geographic positioning. Silvereyes, captured in breeding areas in Tasmania, were physically transported to a location along their migratory route and assessed for orientation during autumn migration. Adults and juveniles exhibited seasonally appropriate, northeasterly orientation (19° and 23° east of magnetic North, respectively) when tested under the natural geomagnetic field. Birds were then exposed to changes in the magnetic field that simulated either southern (SimS) or northern (SimN) locations near the beginning and end, respectively, of their migratory route. Inexperienced juveniles continued to show seasonally appropriate orientation (3° and 358°, respectively) in both SimS and SimN magnetic fields. Adults, in contrast, exhibited changes in orientation but only when the experimental magnetic field was consistent with a geographical displacement that should require compensatory orientation (i.e., SimN). Adults exposed to a SimS magnetic field continued to show seasonally-appropriate orientation to the North (0°). However, adults exposed to magnetic fields simulating locations beyond their wintering areas (SimN) altered their orientation significantly, orienting bimodally and perpendicular (123°–303°) to their seasonally appropriate migratory direction. These results are consistent with the presence of an age- or experience-dependent magnetic geographic position sense in migratory Australian Silvereyes.

Magnetic Orientation in Solenopsis sp. Ants

It is known that magnetic fields affect ants behavior. It has been shown that Solenopsis ants are sensitive to magnetic fields but there is no experimental evidence for magnetic orientation. In this paper experiments were done to verify the magnetic orientation of Solenopsis sp. ants. The spontaneous orientation of ants in a circular arena was studied in two different magnetic conditions: in the natural geomagnetic field and under an altered magnetic field, with the horizontal geomagnetic axis shifted in 90 o. Our results show that ants consistently change their orientation direction when the magnetic field was altered. Axial circular statistics analysis showed that, in the absence of other cues, ants orient spontaneously to the horizontal geomagnetic field axis. The present paper shows for the first time magnetic orientation in Solenopsis sp. ants.

Experimental study of domestic waste material using magnetic resonance measurements

ABSTRACTIn this paper, we present results of a laboratory and in situ study of a domestic waste landfill using magnetic resonance measurements. For our study, we used a laboratory Earth’s field nuclear magnetic resonance (NMR) instrument developed at LTHE and a large‐scale commercial magnetic resonance sounding (MRS) system NUMISLITE from IRIS Instruments. We show that NMR could be a tool for investigating different processes in water‐saturated waste samples.Our results show that domestic waste material contains ferromagnetic or paramagnetic particles that perturb the homogeneity of the geomagnetic field at a microscopic scale and render an NMR signal short. Consequently, only the spin echo technique can be applied for measuring. At a macroscopic scale, waste and different buried objects may also perturb the natural geomagnetic field. While investigating the landfill, we observed that magnetic anomalies (±2500 nT) are localized around some cells. This is probably linked to the presence of a higher percentage of metallic objects within the waste disposal.Our first appraisal of the possibility of investigating water‐saturated waste in a laboratory using an Earth’s field NMR instrument shows that, with existing instruments, waste samples can be studied when the dry density of waste is less than approximately 450 kg/m3.Because the relaxation times of magnetic resonance signals in landfill may be short ( and ), existing large‐scale MRS instrumentation is not adapted to the investigation of domestic waste landfills.

Chicks incubated in hypomagnetic field need more exogenous noradrenaline for memory consolidation

The geomagnetic field (GMF) is one of the essential characteristics of the terrestrial environment but does not apply in outer space. The elimination of GMF may interfere with the normal activities of life in many aspects. Previous behavioral experiments have found that long-term memory is impaired in chicks incubated in a near-zero magnetic environment (i.e. hypomagnetic field or HMF). The present study was designed to evaluate the possible involvement of noradrenergic change in the functional abnormality observed before. A HMF space was produced by nullifying the natural GMF with three pairs of Helmholtz coils. The one-trial passive avoidance learning paradigm was performed on day-old chicks incubated in either the HMF space or the natural GMF. Exogenous noradrenaline was administered by intracerebral injections and the effect on memory consolidation was compared between the two categories of subjects. In the behavioral paradigm, the HMF chicks had a higher elimination rate than the GMF chicks and displayed a significant reduction in overall responsiveness. The administration of moderate doses (0.1–0.5 nmol/hemisphere) of noradrenaline led to fairly good memory retention in GMF chicks but had little effect on HMF chicks. However, long-term memory of HMF chicks could be elevated to the normal level by much higher doses (1.0–1.75 nmol/hem) of the drug. These results suggest that prolonged exposure to HMF may induce disorders in the noradrenergic system in the brain and indicate a potentiality of counteracting the ill-effect of GMF deprivation with appropriate pharmacological manipulation.

Tubulin assembly is disordered in a hypogeomagnetic field

Although the effect of a magnetic field on functions of many proteins has been reported, tubulin assembly in a hypogeomagnetic field (HGMF) has not yet been characterized. Here, we show disorder in tubulin self-assembly in an HGMF. Absorbance at 350 nm, commonly used to monitor tubulin self-assembly, was altered in the HGMF, providing evidence for the effects of HGMF on tubulin. Measurements of intrinsic fluorescence (335 nm) also revealed a disordered change in tubulin conformation during assembly in the HGMF. Under the same conditions, microtubule-like filaments were not observed by electron microscopy, with the exception of amorphous oligomers. Incubation of tubulin with tau in the natural geomagnetic field (GMF) yielded microtubule-like filaments, while only amorphous oligomers were observed following the incubation in the HGMF. This distinction suggests that tubulin assembly depends upon the GMF, and that elimination of the GMF induces disorder in tubulin organization.