Multifractal analysis of K+ channel activity

Autor: A. A. Grinevich, V. N. Kazachenko, M. E. Astashev
Rok vydání: 2007
Předmět:
Zdroj: Biochemistry (Moscow) Supplement Series A: Membrane and Cell Biology. 1:169-175
ISSN: 1990-7494
1990-7478
DOI: 10.1134/s1990747807020109
Popis: The Multifractal version of the Detrended Fluctuation Analysis was used for the study of non-stationary dwell time series of Ca2+-activated K+ channels (KCa channels) in cultured kidney Vero cells and of voltage-dependent K+ channels (Kv channels) in mollusc (Lymnaea stagnalis) neurons. The data obtained can briefly be summarized as follows: (i) The generalized fluctuation function F q (l) strongly depends on the index (order) q; for monofractal time series, such dependence is nonexistent; (ii) The relationship between the scaling exponent τ commonly employed in standard multifractal analysis and q is characterized by two slopes and a transitory region, whereas monofractal processes are characterized by the linear dependence; (iii) The relationship between the singularity spectrum f(h) and the Hurst exponent h is bell-shaped, while in the case of monofractal processes it is represented by a single point f(h) = 1. Random mixing of the time series resulted in the narrowing of the spectrum f(h) and a shift of f(h) towards the value more characteristic of stochastic (monofractal) processes (h ∼ 0.5). It is concluded that the activities of both KCa channels in kidney Vero cells and of KV channels in mollusc (Lymnaea stagnalis) neurons can be characterized as multifractal processes.
Databáze: OpenAIRE
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