Noise and biological systems

Biological and electronic systems have a lot in common. Still, there is one remarkable difference between the two systems; biological systems are always subject to noise which interferes with their reliability. Biological noise is inevitable as it is derived from smallness of cells. Biological systems acquired ability to resist noise and even to take advantage of noise to enhance their functionalities. We study noisy aspects of biological systems by stochastic process theories.

生物の機構は電気回路などの工学システムと多くの類似性を持ちます．しかし，通常の電気回路のような工学的なシステムと，生物システムの最も大きな違いは，生体システムには多くのノイズが付き物だという点です．このようなノイズは細胞の小ささから由来するため，物理的に避けることが出来ません．ノイズのある不確実な系は，決定的な系とは本質的に振る舞いが異なります．生物は進化の過程でノイズに対するロバスト性や，ノイズを積極的に利用する機構を獲得しています．ノイズ環境下における生物システムの振る舞いを理論的に解析しています．

• Yoshihiko Hasegawa and Masanori Arita. Fluctuating Noise Drives Brownian Transport, Journal of the Royal Society Interface, vol.9, p.3554-3563, 2012
• Yoshihiko Hasegawa and Masanori Arita. Escape Process and Stochastic Resonance Under Noise Intensity Fluctuation, Physics Letters A, vol.375, p.3450-3458, 2011
• Yoshihiko Hasegawa and Masanori Arita. Noise-Intensity Fluctuation in Langevin Model and Its Higher-Order Fokker-Planck Equation, Physica A, vol.390, p.1051-1063, 2011
• Yoshihiko Hasegawa and Masanori Arita. Bistable Stochastic Processes in the q-Exponential Family, Physica A, vol.389, p.4450-4461, 2010