Fractional calculus is a mathematical approach dealing with derivatives and integrals of arbitrary and complex orders. Therefore, it adds a new dimension to understand and describe basic nature and behavior of complex systems in an improved way. Here we use the fractional calculus for modeling electrical properties of biological systems. We derived a new class of generalized models for electrical impedance and applied them to human skin by experimental data fitting. The primary model introduces new generalizations of: 1) Weyl fractional derivative operator, 2) Cole equation, and 3) Constant Phase Element (CPE). These generalizations were described by the novel equation which presented parameter related to remnant memory and corrected four essential parameters We further generalized single generalized element by introducing specific partial sum of Maclaurin series determined by parameters We defined individual primary model elements and their serial combination models by the appropriate equations and electrical schemes. Cole equation is a special case of our generalized class of models for Previous bioimpedance data analyses of living systems using basic Cole and serial Cole models show significant imprecisions. Our new class of models considerably improves the quality of fitting, evaluated by mean square errors, for bioimpedance data obtained from human skin. Our models with new parameters presented in specific partial sum of Maclaurin series also extend representation, understanding and description of complex systems electrical properties in terms of remnant memory effects.

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The features of the moving large polaron are investigated within Holstein's molecular crystal model. The necessity to account for the phonon dispersion is emphasized and its impact on polaron properties is examined in detail. It was found that the large polaron dynamics is described by the nonlocal nonlinear Schrödinger equation. The character of its solutions is determined by the degree of nonlocality, which is specified by the polaron velocity and group velocity of the lattice modes. An analytic solution for the polaron wavefunction is obtained in the weakly nonlocal limit. It was found that the polaron velocity and phonon dispersion have a significant impact on the parameters and dynamics of large polarons. The polaron amplitude and effective mass increase while its spatial extent decreases with a rise in the degree of nonlocality. The criterion for the stability of large polaron is formulated in terms of the values of the degree of nonlocality, the magnitude of the basic energy parameters of the system and the polaron velocity. It turns out that the large polaron velocity cannot exceed a relatively small limiting value. A similar limitation on large polaron velocity has not been found in previous studies. The consequences of these results on polaron dynamics in realistic conditions are discussed.

In this paper, we develop the new physical-mathematical time scale approach-model applied to BaTiO 3 -ceramics. At the beginning, a time scale is defined to be an arbitrary closed subset of the real numbers R, with the standard inherited topology. The time scale mathematical examples include real numbers R, natural numbers N, integers Z, the Cantor set (i.e. fractals), and any finite union of closed intervals of R. Calculus on time scales (TSC) was established in 1988 by Stefan Hilger. TSC, by construction, is used to describe the complex process. This method may be utilized for a description of physical, material (crystal growth kinetics, physical chemistry kinetics -for example, kinetics of barium-titanate synthesis), biochemical or similar systems and represents a major challenge for nowadays contemporary scientists. Generally speaking, such processes may be described by a discrete time scale. Reasonably it could be assumed that such a "scenario" is possible for discrete temperature values as a consolidation parameter which is the basic ceramics description properties. In this work, BaTiO 3 -ceramics discrete temperature as thermodynamics parameter with temperature step h and the basic temperature point a is investigated. Instead of derivations, it is used backward differences with respect to temperature. The main conclusion is made towards ceramics materials temperature as description parameter.

In this paper, Caputo based Michaelis -Menten kinetic model based on Time Scale Calculus (TSC) is proposed. The main reason for its consideration is a study of tumor cells population growth dynamics. In the particular case discrete-continuous time kinetics, Michaelis-Menten model is numerically treated, using a new algorithm proposed by authors, called multistep generalized difference transformation method (MSGDETM). In addition numerical simulations are performed and is shown that it represents the upgrade of the multi-step variant of generalized differential transformation method (MSGDTM). A possible conditions for its further development are discussed and possible experimental verification is described.