Kavokin Kirill
Spin Optics Laboratory, St. Petersburg State University, St. Petersburg, Russia.
I.M.Sechenov Institute of Evolutionary Physiology and Biochemistry RAS, St. Petersburg, Russia.
PLoS One. 2017 Mar 15;12(3):e0173887. doi: 10.1371/journal.pone.0173887. eCollection 2017.
While many properties of the magnetic compass of migratory birds are satisfactory explained within the chemical model of magnetoreception, its extreme sensitivity to radio-frequency magnetic fields remains a mystery. Apparently, this difficulty could be overcome if the magnetoreceptor model were augmented with a magnetite nanoparticle, which would amplify the magnetic field at the position of the magneto-sensitive cryptochrome molecule. However, comparison of the radio-frequency power used in the experiment with intrinsic magnetization noise of such a particle, estimated from the theory of fluctuations, shows that the required sensitivity cannot be reached with realistic parameters of iron-oxide nanocrystals.
虽然候鸟磁罗盘的许多特性在磁感受的化学模型中得到了令人满意的解释,但其对射频磁场的极端敏感性仍然是个谜。显然,如果在磁受体模型中增加一个磁铁矿纳米颗粒,这个难题或许可以克服,该颗粒会在磁敏隐花色素分子的位置放大磁场。然而,将实验中使用的射频功率与根据涨落理论估算的这种颗粒的固有磁化噪声进行比较后发现,以氧化铁纳米晶体的实际参数无法达到所需的灵敏度。