Influence Of Geomagnetic Field Research Articles

Effect of the Static Magnetic Fields on the Circadian Rhythm in Arabidopsis thaliana

The influence of geomagnetic field on various biological processes is certainly an interesting research field, and more work is beingperformed across the globe. However, the impact of varying magnetic flux density on plant circadian rhythms has not yet beencompletely investigated. Different researchers have mostly focused their attention on the molecular workings of circadian rhythms invarious plant systems and the circadian architecture of transcriptomes under varying conditions. The present investigation evaluatedthe influence of variable geomagnetic field on the expression of genes that are under the control of circadian rhythm, and checkedwhether the expression pattern of these genes with respect to time (circadian nature) under different magnetic flux density changesor not in Arabidopsis seedlings. This study examined the impact of varying magnetic flux densities on the mRNA expression levels ofsix genes in Arabidopsis thaliana during the final 33 hours of their total 120 hour growth period. A. thaliana seedlings were subjectedto four distinct magnetic flux densities (0, 25, 50, and 90 μT), and the abundance of transcripts for chlorophyll a/b binding protein 4,the large subunit of RuBisCO, rubisco activase, chalcone synthase, porphobilinogen synthase, and phytoene dehydrogenase genes wasexamined. While the present study’s findings lend credence to the idea that the aforementioned genes are differentially expressed inresponse to changes in magnetic flux density, it also proved that the circadian nature of these genes was largely unaffected, with theirexpression pattern remaining largely unaltered regardless of the strength of the magnetic field.

Роль геомагнитных возмущений в развитии окклюзионных поражений ретинальных вен (обзор литературы)

The review presents modern information on pathogenesis of retinal vein occlusions and risk factors for their formation. An in-depth analysis of role of external factors, among which influence of geomagnetic field and geomagnetic disturbances, has been carried out. The definition is given to such notions as magnetosensitivity, its pathogenetic mechanisms, and their role in formation of acute vascular events. Information about influence of geomagnetic disturbances on the formation of retinal vein occlusion is presented. Key words: geomagnetic disturbancies; magnetosensitivity; retinal vein occlusion.

Program determination of the low frequency geomagnetic field and their influence on biological objects.

The program of computations of spectrum of the geomagnetical field is developed. It was confirmed, that the most values of tension of the geomagnetical field at magnetic storms arise up on frequencies below 1 Hz. On the basis of an algorithm developed the characteristics of the super low-frequency geomagnetic field at the frequency range < 1 Hz are calculated. The analysis at frequencies 0.1, 0.5, 0.01, 0.05, 0.001, 0.0001 Hz allows to reveal the largest intensity of the low-frequency geomagnetic field at 0.0001 Hz. Its oscillation rate is most sensitive for biological organisms to the magnetic storm occurrence. Some examples of influencing of low frequency fluctuations of the geomagnetical field on biological objects are considered. The ways of their computations are given. Biological objects which can possess sensitiveness to influences of the weak magnetic fields are considered. The results obtained are used to consider some aspects of the mechanism of the low-frequency geomagnetic field influence on biological objects.

Influence of Geomagnetic Field on the Long-Range Propagation of Relativistic Electron Beam in the Atmosphere

It is known that Earth’s atmosphere and geomagnetic field affect the propagation of an artificial electron beam; many previous studies have neglected the effect of their variation on the propagation dynamics. In this article, parameters in envelope equations were modified according to the International Geomagnetic Reference Field (IGRF) model and MSIS-90 atmosphere model; then, the model was constructed to study the propagation of artificial electron beam in the atmosphere. Calculation of the beam’s energy loss and radial expansion in propagation showed that the variation of geomagnetic field intensity can be the main reason for the radial pinch in the altitudes above 150 km, and the ambient particle density plays a dominant role in the beam’s radial expansion in altitudes below 150 km. The Monte Carlo model was used to simulate the interactions of a relativistic (1 MeV) electron beam with the atmosphere in the altitude range 100–150 km. Energy deposition density demonstrates that the geomagnetic field can limit the radial expansion of the beam. The relativistic electron beam was emitted horizontally in the atmosphere. The geomagnetic field can limit the beam’s radial expansion and cause the beam to propagate along the field line, irrespective of the direction in which the beam is emitted.

Analysis of the Impact of Long‐Term Changes in the Geomagnetic Field on the Spatial Pattern of the Weddell Sea Anomaly

AbstractWe simulated the impact of long‐term changes in the geomagnetic field on the spatial pattern of the Weddell Sea Anomaly (WSA). The Weddell Sea Anomaly, belonging to the region near the tip of the Antarctic Peninsula, Falklands, and surrounding seas, is the best‐known example of ionospheric reversed diurnal cycle. This paper investigates whether and to what extent long‐term changes in the geomagnetic field influence spatial morphology of the WSA. The major concept centers on a normalized density difference index, serving as a measure of difference between dayside and nightside ionospheric density. Through combined analysis of in situ ionospheric electron density data from past mission CHAMP, ongoing ESA mission Swarm, and simulations based on the NCAR TIEGCM model, we examine changes in the spatial pattern of the WSA‐like anomalies, which could be linked to long‐term changes in the geomagnetic field. A series of simulations provides theoretical analysis of changes in the morphology of the WSA on time scales longer than several decades. Numerical analysis shows that from the time when the WSA was discovered (around 1960) till present, maximum of the WSA has migrated by approximately 7° in longitude towards the Pacific Ocean, showing clear westward drift, consistent with temporal evolution of the geomagnetic dipole component.

Latitudinal and Longitudinal Variations of Earth’s Magnetic Force on Electrified Hydrometeors

In this study, a hypothesis is proposed about the possible effect of Geomagnetic field (GMF) on the charge structure of a thundercloud based on Lorentz force equation and Fleming’s right-hand rule. To prove this hypothesis, a simulation using the12th International Geomagnetic Reference Field (IGRF) model has been made. In this simulation, latitudinal and longitudinal variations of Earth’s magnetic force on electrified hydrometeor are considered. With regard to the simulation results, the electrified hydrometeor’ velocity vector is noteworthy to consider GMF effect on charge structure of thundercloud. Furthermore, the influence of GMF on charge separation could clarify the reason of some real thunderstorm observations. Finally, the effect of GMF on charge structure of thunderclouds might be a mechanism for electric field development and lightning initiation.

Influence of geomagnetic field on the imaging performance of a streak tube

Abstract Streak cameras are widely used as ultrafast diagnostic tools in several research fields as the spatiotemporal measurement is of great significance in physics, chemistry, and biomedical research. However, as action objects, electron beams inside streak tubes are easily affected by the surrounding environment, which may lead to deterioration in the performance. In this study, the influence of a geomagnetic field on a streak tube is verified through a simulation. Based on the simulation results, the variation in the image shape due to the geomagnetic field and the overall camera imaging characteristics are analysed theoretically for the first time. The experimental result demonstrates that the imaging characteristics are better after a theoretical analysis is conducted and the final image is adjusted according. We discuss how this analysis can further develop other types of electron optical imaging systems and experiments.

ON THE NORMALIZATION OF THE REACTIVE LOAD OF ELECTRIC TRANSMISSION OF INDUSTRIAL-LENNY AND ELECTRIC POWER CONSUMERS ELECTRICALLY CONSUMED

A new mathematical quantum physics-based approach to the process of power transmission to the industrial electricity consumers and the ones equated to them, which allows to improve the power supplying quality of the mentioned consumers and save electric power resources of a country is offered. Wherein electric power system voltage is considered as a potential form of electromagnetic energy and commercial product of electric power industry, which is a base one of any economy. The power transmission organizations, with the help of their and consumers’ networks, supply voltage to a receiving point in the power supplying system of specific consumers at the level of quality established by the state. It is known that the main voltage quality indicator is a level of its deviation from the nominal value. In the paper the voltage drops, linked with reactive consumer load, are proposed to be optional and completely dependent on its run mood.That is why it is offered to normalize (control) the reactive load coefficient value for each of the con-sumers in the way that the voltage deviation of the receiving point in the maximal load mood of power sup-plying system does not exceed 5 % of the nominal value. Taking into account that an integral part of any electric device is its electromagnetic field the one (field) of power supplying system can be presented in the form of a quanton, whose electrons of polarized molecules revolve in the two mutually perpendicular di-rections - lengthwise and crosswise the direction of electric transmission in the volume of solid angle 45 de-gree under the influence of geomagnetic field.

Influence of geomagnetic activity and atmospheric pressure in hypertensive adults.

We performed a study of the systolic and diastolic arterial blood pressure behavior under natural variables such as the atmospheric pressure and the horizontal geomagnetic field component. We worked with a group of eight adult hypertensive volunteers, four men and four women, with ages between 18 and 27years in Mexico City during a geomagnetic storm in 2014. The data was divided by gender, age, and day/night cycle. We studied the time series using three methods: correlations, bivariate analysis, and superposed epoch (within a window of 2days around the day of occurrence of a geomagnetic storm) analysis, between the systolic and diastolic blood pressure and the natural variables. The correlation analysis indicated a correlation between the systolic and diastolic blood pressure and the atmospheric pressure and the horizontal geomagnetic field component, being the largest during the night. Furthermore, the correlation and bivariate analyses showed that the largest correlations are between the systolic and diastolic blood pressure and the horizontal geomagnetic field component. Finally, the superposed epoch analysis showed that the largest number of significant changes in the blood pressure under the influence of geomagnetic field occurred in the systolic blood pressure for men.

A comparison of mesospheric and low‐thermospheric winds measured by Fabry‐Perot interferometer and meteor radar over central China

AbstractWind data observed by a Fabry‐Perot interferometer (FPI) and a meteor radar (MR) deployed in two stations, which are 430 km apart in ground distance, are used to study wind climatology in mesosphere/lower thermosphere over central China and compare between the measurements. A general morphologic similarity of the FPI winds and MR winds is identified with 4 year data since November 2011. At 87 km, the wind vector plots show that the FPI and MR winds agree with each other very well in all months. The zonal winds of both instruments have an apparent semiannual variation with a maximal strength of −20 m/s at around 18:00 UT in equinoctial months, and the meridional winds from both instruments have an apparent annual variation with a maximal strength of −40 m/s at around 15:00 UT in summer months. The correlation coefficients between the measurements of the two instruments are about 0.95 for meridional wind and 0.90 for zonal wind. At 97 km, the wind vector plots show that FPI and MR winds agree with each other from May to October and are obviously different in the rest months. There are very weak semiannual variations at around 18:00 UT for both zonal winds and pronounced annual variation at around 13:00 UT for both meridional winds. The correlation coefficients between the FPI and MR winds are 0.73 for zonal wind and 0.86 for meridional wind, which are overall smaller than that at 87 km. A Gaussian distribution of airglow profile is used to investigate the deviations associated with peak height and full width at half maximum (FWHM) of airglow layer. It is found that the variation of peak height could lead to about 20% variation of correlation coefficients between measurements at the height of 87 km and about 14.8% at the height of 97 km on average. The variation of FWHM could lead to a correlation coefficient variation of about 2.4% and 3.5% at the height of 87 km and 97 km, respectively. Some other reasons, such as the influence of geomagnetic field on meteor trail and the propagation of gravity waves, could also contribute to these differences between measurements.

Influence of magnetic field on the spatial orientation in zebrafish (Danio rerio) (Cyprinidae) and Roach (Rutilus rutilus) (Cyprinidae)

Preferred direction of motion under influence of geomagnetic field and its modifications was registered in zebrafish (Danio rerio) raised in laboratory culture and in roach (Rutilus rutilus) from the Rybinsk Reservoir. In the geomagnetic field, specimens of zebrafish prefer two opposite directions oriented towards the north and south, while they prefer towards east and west at 90° turning of the horizontal component of geomagnetic field. The specimens of roach in the geomagnetic field prefer only the direction oriented towards east–northeast. This direction coincides with the direction along the canal where roach was sampled to the main river channel part of the Rybinsk Reservoir. At 90° rotation of the horizontal component of geomagnetic field, the direction turns to the south–southeast. The reasons for selection of certain directions in the geomagnetic field are discussed.

Geomagnetic field and climate variability. 1. Spatial-temporal distribution of geomagnetic field and climatic parameters during XX century

Analysis of main geomagnetic field (from IGRF model) and climatic parameters (near surface air temperature and surface pressure) allows us to determine their variability and spatial-temporal relations between them during the 20th. Integral characteristics and dynamics of the above parameters in latitudinal band 40-70 ° N have been investigated, applying one and the same approach. This gives us the possibility to reveal their global and regional characteristics - the differences and similarities between them. Three distinct periods of the spatial-temporal distribution of geomagnetic field intensity have been determined, that could be connected to corresponding periods of mean near surface air temperature evolution during the 20th century: initial global warming (1911-1943); stabilization (end of 1940 s - middle 1970 s); secondary global warming (middle of 1970 s - 2000 s). There is a good correspondence between geomagnetic field, near surface air temperature and pressure spatial distributions during the 20th century. The high coefficient of similarity between integral spatial distributions of geomagnetic field intensity F and surface air temperature T (RFT ) = - 0,83 is quite unexpected. It indicates that relations between them could hardly be a random connection. If there is a causal relation between them, it obviously should be in the direction: geomagnetic filed influence on the temperature and / or surface pressure. The main problem in this case is that the mechanisms of magnetic filed influence on climatic parameters are less investigated and poorly understood. In this paper geomagnetic field is considered to be a first element of the causal chain of processes relating it with Earth's climate. A brief review of resent understanding of solar - geomagnetic field influence on climate shows that the main role in this process is played by galactic cosmic rays. Results presented here are basement for the second part of this paper, where the causal link of the processes connecting geomagnetic field with galactic cosmic rays, ozone and water vapour near the tropopause (with their influence on the radiation balance of the planet and consequently on climate) is thoroughly analysed.

The Calibration Method of Helmholtz Coils for the Permanent Magnet

The current method is presented to calibrate the constant of Helmholtz coils. Two measurement methods of magnetic field strength are proposed and compared. In order to improve the accuracy, the influence of geomagnetic field is eliminated by changing direction of the magnetic field of Helmholtz coils. When the magnetic field strength is measured by Guassmeter, the calibration uncertainty is 0.12% (k=2). When the magnetic field strength is measured by Fluxmeter and search coil, the calibration uncertainty is 0.30% (k=2).

Mechanisms of Geomagnetic Field Influence on Gene Expression Using Influenza as a Model System: Basics of Physical Epidemiology

Recent studies demonstrate distinct changes in gene expression in cells exposed to a weak magnetic field (MF). Mechanisms of this phenomenon are not understood yet. We propose that proteins of the Cryptochrome family (CRY) are “epigenetic sensors” of the MF fluctuations, i.e., magnetic field-sensitive part of the epigenetic controlling mechanism. It was shown that CRY represses activity of the major circadian transcriptional complex CLOCK/BMAL1. At the same time, function of CRY, is apparently highly responsive to weak MF because of radical pairs that periodically arise in the functionally active site of CRY and mediate the radical pair mechanism of magnetoreception. It is known that the circadian complex influences function of every organ and tissue, including modulation of both NF-κB- and glucocorticoids- dependent signaling pathways. Thus, MFs and solar cycles-dependent geomagnetic field fluctuations are capable of altering expression of genes related to function of NF-κB, hormones and other biological regulators. Notably, NF-κB, along with its significant role in immune response, also participates in differential regulation of influenza virus RNA synthesis. Presented data suggests that in the case of global application (example—geomagnetic field), MF-mediated regulation may have epidemiological and other consequences.

Influence of geomagnetic field on the motion of low satellites

The first aim of the present work is to compute a more accurate and recent model for the Earth’s magnetic field. The second aim is to determine the effects of the Earth’s magnetic field on the motion of a charged artificial satellite to evaluate the variations of the orbital elements of the satellite due to these effects. The magnetic field and its variation with time have been studied at different heights, longitudes and latitudes. The geomagnetic field is considered as a multiple potential field and the electrical charge of the satellite is assumed to be constant. A new computer code has been constructed to follow the components of the magnetic field in spherical harmonic models. The Gauss equations are solved numerically. The results concentrate on the computation of the numerical values of orbital perturbation for the case of a low Earth satellite. RS-1 satellite and space craft gravity probe B (GPB) are chosen as cases of studies for a detailed numerical analysis.

Moon shadow by cosmic rays under the influence of geomagnetic field and search for antiprotons at multi-TeV energies

We have observed the shadowing of galactic cosmic ray flux in the direction of the moon, the so-called moon shadow, using the Tibet-III air shower array operating at Yangbajing (4300 m a.s.l.) in Tibet since 1999. Almost all cosmic rays are positively charged; for that reason, they are bent by the geomagnetic field, thereby shifting the moon shadow westward. The cosmic rays will also produce an additional shadow in the eastward direction of the moon if cosmic rays contain negatively charged particles, such as antiprotons, with some fraction. We selected 1.5 × 10 10 air shower events with energy beyond about 3 TeV from the dataset observed by the Tibet-III air shower array and detected the moon shadow at ∼40 σ level. The center of the moon was detected in the direction away from the apparent center of the moon by 0.23° to the west. Based on these data and a full Monte Carlo simulation, we searched for the existence of the shadow produced by antiprotons at the multi-TeV energy region. No evidence of the existence of antiprotons was found in this energy region. We obtained the 90% confidence level upper limit of the flux ratio of antiprotons to protons as 7% at multi-TeV energies.

Environmental Discomfort and Geomagnetic Field Influence on Psychological Mood in Athens, Greece

A multivariate analysis of 4797 cases of patients who were cured of their psychological symptoms and their notes filed by the psychiatric clinic of the Eginition Hospital in Athens, during the year 1994, has been done. The results of this analysis imply significant contribution of environmental variations, expressed by a discomfort index, in the aggravation of psychological symptoms like depression, sleep disturbances, anxiety, aggressiveness, etc. Moreover, geomagnetic field variations expressed by the international geomagnetic index (DST) manifest significant indications that they contribute to the aggravation of sleep disturbances. A clear seasonal variation, with a maximum around August and a minimum at the end of the year, appears in the environmental index, while a double oscillation with a period of about six months is obvious in the geomagnetic index. The same more or less seasonal variation was mirrored in most of the psychological symptoms we analysed in the present study.

Interaction within the ionosphere in the presence of geomagnetic field

Field intensities within the ionospheric medium during nonlinear transient processes due to interactions among different modes of propagation have been derived taking into consideration the influence of geomagnetic field. The expression for angular distribution of power during wave propagation has also been evaluated.

Low Temperature Remanent Magnetization of Fe-Ni Alloy (II)

Magnetic properties of synthetic 29at%Ni-Fe alloy were investigated for the purpose of understanding magnetization process of some meteorites. It was found that a stable remanent magnetization is acquired by cooling the alloy at 77K under the influence of geomagnetic field. This new type of remanent magnetization seems to be due to martensitic transformation from fcc to bcc phase of the alloy during which the crystalline anisotropy becomes zero. Natural remanent magnetization of some meteorites may possibly be of this origin.

Low temperature remanent magnetization of Fe-Ni alloy.

Magnetic properties of synthetic 29at%Ni-Fe alloy were investigated for the purpose of understanding magnetization process of some meteorites. It was found that a stable remanent magnetization is acquired by cooling the alloy at 77K under the influence of geomagnetic field. This new type of remanent magnetization seems to be due to martensitic transformation from fcc to bcc phase of the alloy during which the crystalline anisotropy becomes zero. Natural remanent magnetization of some meteorites may possibly be of this origin.