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• A.K.Vidybida. Estimation of possible selectivity and sensitivity of a cooperative system to low-intensive microwave radiation. Physica A, v.221(1-3), 1995, p.30-40
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  Abstract. Cooperative bistable chemical system is considered as possible mechanism for sensitive and selective reception of low-intensive microwaves in bio-objects. The mechanism is realized in a two-level hierarchical manner with a threshold for signal channeling from first level to the second one. At first stage the microwave signal is percepted in a population of primary receptors represented as molecules of definite species. Each primary receptor has active and non-active conformation. The subpopulations of active and non-active receptors are in thermal equilibrium at physiological temperature, and thermal fluctuations are taken into account. The microwaves are expected to shift the equilibrium to more active receptors when acting at the non-active receptor fundamental frequency of mechanical oscillations. If concentration of active receptors is high enough, the whole bistable system switches from a stable state to another one. Due to thermal fluctuations the switching has a probabilistic nature, and is characterized via a mean waiting time for first switching. The whole system sensitivity is estimated in terms of the waiting time shortening due to microwaves. At the level of primary receptors the sensitivity is described as relative increment of active receptors. It is expected that the individual receptor oscillations are overdamped with quality factor Q = 1. The sensitivity to 1 GHz field with power density 1 mW/cm^2 is estimated. Sensitivity to this field at the level of primary receptors is characterized by the factor 10^{-8} which is indistinguishable from thermal fluctuations at physiological temperature. If the bistable system has maximum volume consistent with spatial homogeneity (the coherent volume), then its sensitivity is estimated as shortening of waiting time by a factor as high as EXP(10^4). The system selectivity is also much better than that of individual primary receptor, and may be expressed by apparent quality factor Q = 10^3.