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The paper presents an improved key to the co-occurring species of Polymerus Hahn, 1831 (Heteroptera, Miridae) based on morphological characters and our new data on the differences between the COI gene DNA sequences of these species. These characters, together with the data stored in the NCBI GenBank, provide the means for accurate and rapid identification of adults and nymphs of Polymerus unciniger Gapon, 2014, P. unifasciatus (Fabricius, 1794), P. cognatus (Fieber, 1858), P. vulneratus (Panzer, 1806), and P. brevicornis (Reuter, 1879). The subgenera Poeciloscytus Fieber, 1858 and Pachycentrum Gapon, 2014 differ considerably in morphological and molecular genetic characteristics. A PCR-RFLP method has been developed for rapid identification of the pest species P. vulneratus. The morphological characters of P. unifasciatus and the COI gene sequences of the forms earlier registered in GenBank as P. unifasciatus and P. microphthalmus (Wagner, 1951) reveal high intrapopulation variability. Polymerus microphthalmus may be a submacropterous form of P. unifasciatus with shortened hemelytra and smaller eyes, while the macropterous form of the latter species is characterized by larger eyes.

The study involved 106 elderly people of the Arctic aged 61-74 years, 42 of them were residents of the Subarctic region (SR) and 64 residents of the Arctic region (AR). Using gas-liquid chromatography there was determined the serum content of saturated fatty acids (SFA): short-chain (SCFA), medium-chain (MCFA) and long-chain (LCFA); and the levels of carbohydrate metabolism parameters were determined by spectrophotometric methods. Correlation analysis showed that elderly people of SR had no significant interrelationships between the contents of SCFA, MCFA and LCFA, since all the correlation dependences were weak (r=0,2-0,29, p=0,08-0,786), against AR with a lower occurrence of high values of glucose (Glu), lactate (Lac) and low pyruvate (Pyr). In AR, with the highest occurrence of high and low values of GIu, the greatest number of its interrelations was noted with LCFA (palmitic, margarine, stearic, behenic, tricosanoic), then with MCFA (myristic, pentadecanoic) and SCFA (pelargonic), low values of Pyr with MCFA (lauric, myristic, ∑MCFA) and SCFA (decanoic), and a slight decrease in the occurrence of high levels of Lac and Lac/Pyr with LCFA (palmitic, margarine, stearic, tricosanoic), MCFA (lauric, tridecanoic) and SCFA (caproic, capric).

Transformations of structure, phase composition, and mechanical properties of 45Cr26Ni33Si2Nb2 alloy during hightemperature (800-1100 °C) tests for longterm strength are investigated. The formation of the G phase of Ni 16 Si 7 Nb 6 was revealed, and the temperature range of its stability was determined. The cor� relation of strength properties with the formation of the G phase at intercrystalline boundaries is found.

The properties of materials of the heat-exchange equipment components of the fast breeder reactor BN-600 after 130000–170000 h of operation at 500–550°C are studied. The effect of long-term aging on the strength, ductility, impact strength, and fracture toughness of 18Cr-9Ni steel (type 304 stainless steel) and its welds is examined. The mechanisms that give rise to changes in the mechanical properties are analyzed on the basis of microstructural and fractographic studies. The predicted degradation of material properties is estimated as a function of operating temperature and time.

A mathematical model of the kinetics of ferrite formation in the structure of pipe steels is developed. It allows for predicting the structural parameters of ferrite as a function of chemical composition, features of the structure of the initial austenite, and cooling mode after hot rolling.

The durability and plasticity of Kh18N9 steel was experimentally studied after its service for 170000 h at temperatures of 500–550°C in various components of an intermediate heat exchanger of a reactor facility. The properties of austenitic metal and the aged metal during operation were compared. The effect of thermal aging on durability and durable plasticity of Kh18N9 steel was simulated.

Results of the development of additive-correlation and multiplicative-correlation methods for a tomographic reconstruction of the distribution pattern of the total bloodstream velocity vector with the help of ultrasound are presented for relatively low frequencies (1–2) MHz, which provide a sufficient penetration depth. The reconstruction of the vector field uses a great body of spatial-correlation data and is closely related to the process of constructing the tomographic image of a given organ as a whole. A spatial cross-correlation of intermediate images is used, which makes it possible to estimate the bloodstream velocity vector independently of the value of the real blood transfer within the total measurement time. Results of numerical simulations for constant and varying distributions of the bloodstream velocity vector in the cross sections of blood vessels are presented.