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It has been shown by experiments, that spherical tungsten microparticlein etching solution under the ultrasonic exposure is possible. The process of obtaining consists of two stages. At the first stage, by centrifuging a suspension of tungsten powder with an average particle size of 0.5 microns in the activator – etching from a water solution of potassium hydroxide and potassium ferricyanide, obtained tungsten thin plate of any shape, thickness 1–3 micrometers.

Photodynamic therapy (PDT) of cancer is an advanced application of gold nanostructures. The purpose of the research is to study the morphological changes in the transplanted sarcoma S45 at PDT using nanocomposites based on gold nanorods (GNRs). GNRs synthesized with the germ method and covered by a silicon coating, functionalized by hematoporphyrin, were intratumorally injected in rats with transplanted sarcoma S45. The tumor was irradiated by He-Ne laser with a wavelength of 632.8 nm.

A computer-assisted method for the calculation of scaling factors for refining the quantum-mechanical force fields of polyatomic molecules by the Pulay technique is suggested. The method is an iteration procedure and does not involve the calculation of derivatives of the frequencies of vibrations with respect to the scaling factors.

The work presents an example of a system with chaotic dynamics built of three rotators by modifying a conservative system with hyperbolic Anosov dynamics. Results of a computational study of chaotic dynamics are considered (portraits of attractors, time dependences of the variables, Lyapunov exponents, and spectra) and good correspondence is observed between the dynamics on the attractor of the proposed system with the reduced model, characterized by the Anosov dynamics at appropriately defined energy.

A mathematical model of human cardiovascular system autonomic regulation is proposed having the form of differential equation set. Some equations of the model contain terms with time delay. The spectral analysis shows that the proposed model exhibits better qualitative and quantitative coincidence with experimental data than the known models.

The calculations of the lengths of hydrogen bridge and frequencies of vibrations of bonds in the formation of hydrogen bonds skatole, pyridine and pyrrole with the water molecules in the approximation of B3LYP/6-31G(d,p). The calculations of model potentials of intermolecular interaction of the molecules on the basis of formulas Lennard–Jones and Morse, allowed to account for changes in the length of hydrogen bonds depending on the number of water molecules participating in the formation of complexes.

In this work, human lens pathology in different forms of the cataract was studied. Two hundred twenty patients with a cataract (220 eyes) were included in the study. Morphological, immunohystological and immunocytochemical investigations of both lens capsule and substance with antibodies to α- (α-А and α-В), β-, and γ- crystallines were carried out. Diabetic patients revealed a more pronounced expression of α- and β-B crystallin compared with a group of patients with age-related cataracts. Correlation between composition of the crystallines in a lens and its density was demonstrated.

In this article the results of numerical modeling of soliton’s collision in dispersion oscillating fiber are presented. Nonlinear Schroedinger equation for modelling was used. Different propagation regimes of the couple of solitons are considered. One of these results is merging of two solitons into high-intensity pulse.

Algorithms for vibrational analysis of the excited electronic states of molecules and calculations of molecular structure at electronic excitation are described. Algorithms are realized in the form of special programs. Basic data of programs are described. All initial data for this complex are formed on the basis of the molecular dynamics and quantum models. Solution algorithms of the inverse vibronic task allowing to estimate frequencies of normal modes, force fields in the raised electronic conditions and to calculate molecular geometry changes at electronic excitation are developed.