Possible Influence Of Magnetic Fields Research Articles

Inhibition of Angiogenesis Mediated by Extremely Low-Frequency Magnetic Fields (ELF-MFs)

The formation of new blood vessels is an essential therapeutic target in many diseases such as cancer, ischemic diseases, and chronic inflammation. In this regard, extremely low-frequency (ELF) electromagnetic fields (EMFs) seem able to inhibit vessel growth when used in a specific window of amplitude. To investigate the mechanism of anti-angiogenic action of ELF-EMFs we tested the effect of a sinusoidal magnetic field (MF) of 2 mT intensity and frequency of 50 Hz on endothelial cell models HUVEC and MS-1 measuring cell status and proliferation, motility and tubule formation ability. MS-1 cells when injected in mice determined a rapid tumor-like growth that was significantly reduced in mice inoculated with MF-exposed cells. In particular, histological analysis of tumors derived from mice inoculated with MF-exposed MS-1 cells indicated a reduction of hemangioma size, of blood-filled spaces, and in hemorrhage. In parallel, in vitro proliferation of MS-1 treated with MF was significantly inhibited. We also found that the MF-exposure down-regulated the process of proliferation, migration and formation of tubule-like structures in HUVECs. Using western blotting and immunofluorescence analysis, we collected data about the possible influence of MF on the signalling pathway activated by the vascular endothelial growth factor (VEGF). In particular, MF exposure significantly reduced the expression and activation levels of VEGFR2, suggesting a direct or indirect influence of MF on VEGF receptors placed on cellular membrane. In conclusion MF reduced, in vitro and in vivo, the ability of endothelial cells to form new vessels, most probably affecting VEGF signal transduction pathway that was less responsive to activation. These findings could not only explain the mechanism of anti-angiogenic action exerted by MFs, but also promote the possible development of new therapeutic applications for treatment of those diseases where excessive angiogenesis is involved.

A possible influence of magnetic fields on the rotation of gas in NGC 253

The magnetic fields that are present in the galaxy NGC 253 are exceptionally strong. This means that they can influence the rotation of matter and hence the mass-to-light ratio. In this context, we address the issue of the presence of a non-baryonic dark matter halo in this galaxy.

Investigation of the Magnetic Field Influence of Permanent Adjustable Magnets Matrix on the Whole Positioning Mechanism and Levitating Diamagnetic object

Abstract This article deals with problem solution affecting the magnetic field of permanent magnets by change of their position. This article proves the possibility of magnetic field influence on individual construction parts of a positioning mechanism. The first part of the article deals with the problem of magnetic surface levitation of diamagnetic object and with the description of principle of mechatronic positioning mechanism. Specifically, functions of individual construction parts in term of mechanics are described. Positioning levitating mechanism uses for magnetic field generation the matrix NdFeB 32, which is the matrix of permanent magnets arranged in a particular configuration. Linear actuators working on piezoelectric principle were chosen for magnets positioning. The next part of this article deals with numerical solution of magnetic field using calculation software FEMM, for five different configuration positions of permanent magnets. Using the postprocessor mechanism, outputs, for magnetic induction, for lines of force and for vector fields of each position, are subsequently created. In almost the last part the calculation of energies and forces acting in direction of magnetic field axes X and Y is done. The conclusion involves a summary of the possible influence of magnetic field by the change of magnets position and its subsequent influence on the levitating pyrolitic graphite, which is represented by the diamagnetic object.

Embedded, Self‐Gravitating Equilibria in Sheetlike and Filamentary Molecular Clouds

Numerical solutions of the isothermal Lane-Emden equation corresponding to self-gravitating gaseous cores embedded within a finite density envelope of overall cylindrical symmetry are presented. These structures may be members of a fragmentation hierarchy proceeding from sheets to filaments to elongated, prolate clumps. The embedded solutions are the first of their kind and, as such, represent a significant improvement on the isolated cloud paradigm used almost exclusively by previous authors. The properties of the equilibria are in reasonable agreement with observations of dense molecular cores in star-forming clouds, despite the fact that there is only one free parameter in the models. We show that this parameter may be identified with the critical wavelength for instability in the parent filament. The implications of further fragmentation and the possible influence of magnetic fields are discussed briefly.

Combined effects of hydrogen and magnetization on the tensile properties in 2.25Cr1Mo steel

Since the 1950's, there has been much effort to examine the influence of magnetic field on mechanical properties of ferromagnetic metals and alloys. It has been well-documented that lattice defects can influence the magnetic behavior, for example, the change of magnetic susceptibility of steels during plastic deformation or fatigue loading, or the Barkhausen effect, which is caused by the interaction of moving domain walls with lattice imperfection. The present paper is one part of the work to investigate the influences of magnetic field and hydrogen charging on mechanical properties of iron and its alloys. The 2.25Cr-1Mo (ASTM A387) steel was chosen because hydrogen embrittlement of this steel had been widely investigated and the response to hydrogen charging was well-known. So the possible influence of magnetic field could be separated.

On a Possible Influence of Magnetic Fields on the Structure of a Disk Formed During Accretion of Plasma in Binary Systems

During accretion of plasma in binary systems containing compact objects magnetic fields are most likely to become arranged quickly, grow and fully determine the disk structure. The disk divides into separate dense clots, and a corona appears over the equatorial plane of the system. In the corona magnetic lines of force reconnect and beams of relativistic particles are generated.

Summary-Introduction

Speaking on localized velocity fields on the Sun, we mean the velocity fields in active regions on the disk. The experimental data used to picture these fields are based mainly on 1) the observations of Doppler shifts of spectral lines, 2) the form (asymmetry) of line profiles, 3) moving picture process in monochromatic, mainly Hα and H or K, light. However the big skin-time of solar plasma makes these data insufficient to get an adequate and complete idea about the motions in active regions, and we must also take into account the available observational data about magnetic fields in these regions. Somewhere the state of affairs permits one to disregard the possible influence of magnetic fields on the picture of velocity fields But these occasions are comparatively rare, because the main source of solar activity is closely, but in a not quite recognized way, connected with magnetic activity of the Sun. This is why we should in our talk consider as closely as possible both subjects—the motions in active regions and their magnetic fields. The best illustrations of the necessity of such a mode of consideration are the velocity fields in sunspots.

Collision of Two Highly Ionized Clouds of Gas

If two rarefied masses of gas collide at a sufficiently high speed, their relative motion will be stopped by a collective plasma instability, rather than by collisions of individual particles. This is true even if the gases are initially non-ionized. In the present note, the possible influence of magnetic fields is ignored for the most part, but a criterion is found to decide under what conditions the collective interaction remains dominant even when they cannot be ignored. It seems that the neglect of magnetic effects may be justified, for example, in the case of two galaxies in collision at a relative speed of 1000 km/sec. The magnetic energy density here is (1/8π)H2∼4X10−12 erg/cm3 (with H∼10−5 gauss), which is much less than the kinetic energy density 1/2NmU2∼8X10−9 erg/cm3 (with N∼1 particle per cm3).

Collision of Two Highly Ionized Clouds of Gas

If two rarefied masses of gas collide at a sufficiently high speed, their relative motion will be stopped by a collectlve plasma instability rather than by collisions of individual particles. The possible influence of magnetic fields is ignored for the most part, but a criterion is found to decide uader what conditions the collective interaction remains domiuant even when they cannot be ignored. (W.D.M.)