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Using the results from previous modeling of the ball and chain inactivation of the potassium channels we try to model the inactivation of the NaV 1.5 sodium channels in adult and neonatal form. The (fast) inactivation of sodium channels differs from the inactivation of the potassium channels by the use of a inactivating hinge rather than a ball on a chain. The adult and neonatal variants of the channel differ mostly in a charged amino acid residue located on the extracellular side. We show that a drift caused by this residue is sufficient to describe the differences in inactivation between the two forms of the NaV 1.5. We use the survival probability, the patch-clamp measurable parameter, to discriminate between the cells of different metastaticity.

To improve the process of ethanol dehydration, asymmetric chitosan membranes were prepared and applied in the pervaporation process. A porous structure was obtained by adding absolute ethanol into chitosan solution. Fabricated membranes were comprehensively characterized by means of contact angle measurements, degree of swelling analysis, scanning electron microscopy, positron annihilation lifetime spectroscopy and wide angle X-rays scattering, to provide an extensive analysis of their physicochemical properties. The results showed a strong correlation between structure, amount and size of pores, and separation effectiveness of investigated membranes. Additionally, an interesting phenomenon of changing in membrane structure during pervaporation process was observed and was found to cause a nonlinear time dependence of transport and separation parameters. Consequently, the best performance of PV separation of 96 vol% ethanol (feed) was obtained for a membrane prepared from casting solution containing 0.1 ml of absolute ethanol, for which the values of separation factor and permeate flux reached 599.7 and 3.534 kg∙m−2∙h−1, respectively.

Kv 1.2 are voltage-dependent potassium channels of great biological importance. Despite the existence of many reports considering structure - function relations of the Kv 1.2 channel's quantitative domains, some details of the voltage gating remain ambiguous, or even unknown. One of the examples is the range of the S4-S6 domains motions involved in channel activation and gating. Another important question is to what extent the channel geometry influences the observable channel conductance at different voltages, and what mechanism stands behind. Does the narrowing of the pore reduce the conductance by ohmic resistance growth? The answer is surprisingly negative. But it can be explained in an alternative way by considering the fluctuations. To address these problems, we formulate geometric models that mimic the generic features of voltage sensor movement and trigger the movement of the other domains involved in gating. We carry out a complete simulation of S4-S6 domains translations and tilts. The obtained pore profiles allow to estimate the (ohmic) conductance dependency on the voltage. From a family of analysed models, we choose the one most concurring with the experimental data. The results allow to suggest the most probable scenario of S4-S6 domains movement during channel activation by membrane depolarization.

The physicochemical basic laws and their suitable mathematical formulations form a frame of the batch pervaporation process, i.e. the cycled process of removing small traces of volatile impurities from large amounts of a volatile solvent, is described and analyzed in detail. The generic nature of the process, i.e. its exclusively transient behaviour is described as an IBV (initial boundary value) problem with a feed side boundary condition dependent on time. The long time asymptotics is investigated to determine the partition and diffusion coefficients of the trace.

A previously studied drug delivery systems based on 4-arm star shaped polyacids with pentaerythritol core have been proposed as excellent micellar nanocarriers with adjustable characteristics for drug loading and release, including anti-inflammatory drugs. A series of experiments to measure the release of drugs by micelles of various composition were conducted. Here we model this release process by mathematical methods and conclude about the structure and loading capability of the obtained micelles in relation to their composition. Our method is a random walk simulation in a potential field. The results predict a decreasing dependency of the micelle core size on hydrophobic content which relates to the loading capability and release kinetics. We link this phenomenon to the packing quality of the micelle’s core, which is reflected by the values of the drug’s binding energy to the core and the probability to incorporate the drug into the core.

The effect of magnetic field on the solubility of magnetic membranes is investigated. As a result, a conclusion is drawn that the solubility is not altered on the gas–polymer interface but may be altered to a significant degree in the vicinity of the, so-called, magnetic channels that form close to the magnetic particles suspended in the polymer matrix.

Some important physical processes represented by the shape of voltammograms of polyaniline in the phase of oxidation are identified and modelled. The main process, i.e. an angular diffusion by which the motion of conducting polymer subunits take place is described and modelled. To fit a molecular picture of the oxidation process a nontrivial random walk of polymer subunits in configurational space of angles has been performed. A very good agreement between theoretical predictions and experimental data has been obtained.

In this paper, we report on the new method of image compression. The method is based on LZ77 dictionary algorithm. We introduce two modifications such as quantization and noise levels. Experimental results presented in this paper prove that the new method of image compression gives promising results as compared with original LZ77 dictionary algorithm and JPEG2000.

A transition from nondiffusive growth of variance of a particles position to diffusive one of various type, in nonlinear deterministic maps, is discussed. The details of generating regular, subdiffusive and superdiffusive cases are shown.