منابع مشابه
Magnetic Fields Ignorable Magnetic Fields Non Ignorable Magnetic Fields Important Magnetic Fields Dominant
Magnetic fields are considered to be dominant when εB ≥ εK , being εB = B /8π the magnetic energy density and εK = 1/2ρθ 2 the rotation energy density, for a conventional moderate B= 1 μG. They are considered to be negligible when εB < εK for B ∼ 10μG. With no assumption and no theoretical calculation, we show that magnetic fields cannot be ignored in the outer parts of a galaxy like the Milky ...
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Background: In previous investigations, it has been clarified that electromagnetic fields (ELF) can cause some changes in cellular behavior. The aim of this prospective study was to investigate the effect of magnetic field (MF) on human sperm parameters of motility, morphology, and viability. Materials and Methods: Semen samples were collected from 12 fertile men, and were allowed to l...
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We are studied efficacy of high frequency magnetic fields (HFMFs) in treatment of Osgood-Schlatter disease (OSD) including X-rays signs. THELF system apparatus has been used for treatments on 32 young sportsmen (9-15 years). 18 boys and 14 girls, with HFMFs (base frequency 27.125 MHz, with different impulse repetition frequency of 640 Hz and 320 Hz, and absorbed power 3-5 VA). Injured sportsmen...
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The explanation of the observed galactic magnetic fields may require the existence of a primordial magnetic field. Such a field may arise during the early cosmological phase transitions, or because of other particle physics related phenomena in the very early universe reviewed here. The turbulent evolution of the initial, randomly fluctuating microscopic field to a large-scale macroscopic field...
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We discuss the evolution of cosmological magnetic fields from the early universe to the present. We review different scenarios for magnetogenesis in the early universe and follow the subsequent evolution of these fields as the universe recombines. We then focus on the role primordial fields play after recombination in the seeding of stellar and galactic fields and the formation of structure. Co...
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ژورنال
عنوان ژورنال: Nature
سال: 2014
ISSN: 0028-0836,1476-4687
DOI: 10.1038/515202a