Abstract:
:We have previously employed the Lorentz-Langevin model to describe the effects of weak exogenous magnetic fields via the classical Lorentz force on a charged ion bound in a harmonic oscillator potential, in the presence of thermal noise forces. Previous analyses predicted that microT-range fields give rise to a rotation of the oscillator orientation at the Larmor frequency and bioeffects were based upon the assumption that the classical trajectory of the bound charge itself could modulate a biochemical process. Here, it is shown that the thermal component of the motion follows the Larmor trajectory. The results show that the Larmor frequency is independent of the thermal noise strength, and the motion retains the form of a coherent oscillator throughout the binding lifetime, rather than devolving into a random walk. Thermal equilibration results in a continual increase in the vibrational amplitude of the rotating oscillator towards the steady-state amplitude, but does not affect the Larmor orbit. Thus, thermal noise contributes to, rather than inhibits, the effect of the magnetic field upon reactivity. Expressions are derived for the ensemble average of position and the velocity of the thermal component of the oscillator motion. The projection of position and velocity onto a Cartesian axis measures the nonuniformity of the Larmor trajectory and is illustrated for AC and combined AC/DC magnetic fields, suggesting a means of interpreting resonance phenomena. It is noted that the specific location and height of resonances are dependent upon binding lifetime and initial AC phase.
journal_name
Bioelectromagneticsjournal_title
Bioelectromagneticsauthors
Muehsam DJ,Pilla AAdoi
10.1002/bem.20494subject
Has Abstractpub_date
2009-09-01 00:00:00pages
462-75issue
6eissn
0197-8462issn
1521-186Xjournal_volume
30pub_type
杂志文章abstract::Using a crossover experimental design, we evaluated our earlier findings that exposure to a 30 kV/m, 60 Hz electric field for 12 hours per day, 7 days per week for 6 weeks produced significant changes in the performance rates of social behaviors among young adult male baboons. In the crossover experiment, the former c...
journal_title:Bioelectromagnetics
pub_type: 杂志文章
doi:10.1002/bem.2250130506
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journal_title:Bioelectromagnetics
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journal_title:Bioelectromagnetics
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journal_title:Bioelectromagnetics
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journal_title:Bioelectromagnetics
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doi:10.1002/bem.2250150506
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journal_title:Bioelectromagnetics
pub_type: 杂志文章
doi:
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journal_title:Bioelectromagnetics
pub_type: 杂志文章
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更新日期:1997-01-01 00:00:00
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journal_title:Bioelectromagnetics
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journal_title:Bioelectromagnetics
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journal_title:Bioelectromagnetics
pub_type: 杂志文章
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journal_title:Bioelectromagnetics
pub_type: 杂志文章
doi:10.1002/bem.2250140106
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journal_title:Bioelectromagnetics
pub_type: 杂志文章
doi:10.1002/bem.20416
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journal_title:Bioelectromagnetics
pub_type: 杂志文章
doi:10.1002/bem.20122
更新日期:2005-09-01 00:00:00
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journal_title:Bioelectromagnetics
pub_type: 杂志文章,评审
doi:10.1002/bem.10179
更新日期:2003-01-01 00:00:00
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journal_title:Bioelectromagnetics
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更新日期:2002-04-01 00:00:00
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journal_title:Bioelectromagnetics
pub_type: 杂志文章
doi:10.1002/bem.20699
更新日期:2012-04-01 00:00:00
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journal_title:Bioelectromagnetics
pub_type: 杂志文章
doi:10.1002/bem.2250050107
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journal_title:Bioelectromagnetics
pub_type: 杂志文章
doi:10.1002/bem.2250010203
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journal_title:Bioelectromagnetics
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journal_title:Bioelectromagnetics
pub_type: 杂志文章
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journal_title:Bioelectromagnetics
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journal_title:Bioelectromagnetics
pub_type: 杂志文章
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journal_title:Bioelectromagnetics
pub_type: 杂志文章
doi:10.1002/bem.2250040206
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journal_title:Bioelectromagnetics
pub_type: 杂志文章
doi:10.1002/bem.20105
更新日期:2005-09-01 00:00:00
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journal_title:Bioelectromagnetics
pub_type: 临床试验,杂志文章,随机对照试验
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journal_title:Bioelectromagnetics
pub_type: 杂志文章
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更新日期:2013-07-01 00:00:00
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journal_title:Bioelectromagnetics
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journal_title:Bioelectromagnetics
pub_type: 传,历史文章,杂志文章
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更新日期:2007-01-01 00:00:00
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journal_title:Bioelectromagnetics
pub_type: 杂志文章
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更新日期:2012-02-01 00:00:00