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In this work, shear strain modeling in materials consisting of a thin polymer layer (∼15nm), adhesive bonded to a rigid substrate, considered not to be impacted by deformation, was performed. A discrete-continuum model of chains system with a given stiffness with polar groups is developed. The polymer chain was considered in the framework of the persistene model, and the polar groups were based on the lattice model on the tetragonal lattice. It was assumed that the main contribution to the energy of interchain interactions is due to the potential of the polar groups and was calculated using the Metropolis algorithm. The potential interactions between the nearest polar groups of chains included the energy of dipole–dipole interactions (Keesom energy) and the Lennard–Jones potential. It is taken into account that the possible orientations of the polar groups are determined by the average elongation of the chain. Calculations showed that the dependence of free energy on the interchain distance has two minima. The first minimum is characterized by the orientational ordering of the polar groups, the second — by their disordered state. The depth and position of the minima depend on temperature, bending stiffness of the chain, the modulus of the dipole moment of the polar groups and the depth of the potential well in the Lennard–Jones energy. A step-by-step simulation of shear strain in a polymer layer in an orientationally disordered state was carried out. The obtained stress–strain diagrams make it possible to estimate the value of the elastic limit and also to determine the stresses at the points of phase transitions from a disordered to an orientationally ordered state.

A retrospective analysis of treatment was made in 127 adult patients with acute and chronic otitis media complicated by suppurative-inflammatory pathology of the brain. Purulent meningitis was revealed in 52 (40,9%) of hospitalized patients. Meningoencephalitis was often diagnosed in the cases of acute otitis media (15,4%) and in cases of chronic otitis (22,7%). The otogenic brain abscess was detected in 13,5% of otitis media cases and it was noted to be twice frequent (33,3%) in cases of purulent otitis media. The patients 124 (97,6%) have been operated. An extended mastoidotomy and antromastoidotomy were performed in the acute purulent otitis media. An extended radical operation on the ear was applied in case of chronic otitis media. Performance of craniotomy and complete removal of the abscess using modern systems of neuronavigation showed a higher clinical efficacy as compared with transtemporal approach during sanitizing intervention on the ear including the opening and abscess drainage in surgery of otogenic abscesses of the brain.

An analysis of the results of X-ray CT and MR-imaging was made in 46 patients aged from 13 to 78 years old. The patients were admitted to multifield hospitals in Kursk at the period from 2005 to 2015. The research included the nasal cavity, paranasal sinuses, mastoid and pyramid of the temporal bones and the brain. The study could be repeated with bolus contrast medium infusion. The condition of the patients was evaluated in dynamics at intervals of 5-7 days and these data was associated with clinical picture. The authors presents a complex of symptoms and an algorithm of differentiated X-ray diagnostics of diseases of the ENT organs and the main nosological forms of pyoinflammatory diseases of arachnoid membrane and substances of the brain.