Locality is an algorithm characteristic describing a usage level of fast access memory. For example, in case of distributed memory computers we focus on memory of each computational node. To achieve the high performance of algorithm implementation one should choose the best possible locality option. Studying the parallel algorithm locality is to estimate the number and volume of data communications. In this work, we formulate and prove the statements for computers with distributed memory that allow us to estimate the asymptotic volume of data communication operations. These estimation results are useful while comparing alternative versions of parallel algorithms during data communication cost analysis.

In this article, we study the classical solution of the mixed problem in a quarter of a plane and a half-plane for a one-dimensional wave equation. On the bottom of the boundary, Cauchy conditions are specified, and the second of them has a discontinuity of the first kind at one point. Smooth boundary condition is set at the side boundary. The solution is built using the method of characteristics in an explicit analytical form. Uniqueness is proved and conditions are established under which a piecewise-smooth solution exists. The problem with linking conditions is considered.

Taking into account the ideas of the generalized two-level scheme, within the framework of the semiclassical approach to the consideration of the resonant interaction of the light field with matter, an analytical solution to the problem of the evolution of superradiance in a quasi-two-dimensional supercrystal formed by quantum dots is obtained. The calculation was carried out for the physical parameters of a semiconductor structure with quantum-well effects in the presence of resonant nonlinearity and intraband relaxation.

Results of the simulation of spin-dependant tunneling of electrons to the surface states of the titanium dioxide, which are created by adsorbed organic impurities are performed. Tunneling transparency for sunlight generated electrons is calculated by the Phase function method. A ferromagnetic film is considered to be an injector of spin-dependent electrons to the titanium dioxide. It is shown that electron spin polarization at the surface states reaches 10–25 %. It can contribute to the spin enhanced catalysis peeling a surface from organic impurities.

The article deals with the production, sorption and rheological properties of composite materials based on polymer hydrogel and bentonite. It is shown that bentonite prevents the collapse of the hydrogel in aqueous solutions of electrolytes and leads to an increase in the moisture content after the collapse. After several repeated cycles of swelling in water, followed by drying at 60 and 110 °C, the degree of swelling of the composite is higher than that of the hydrogel. In the temperature range from 20 to 40 °C, the polymer hydrogel and the composite are able to withstand at least ten cycles of swelling and drying without changing the degree of swelling.

American mink (Neovison vison) is both a problematic invader and an economically valuable fur breed species in Belarus. The increasing scale of mink breeding for fur and the growing impact of this invasive species on the local ecosystems requires sound, novel strategies for managing both farm and wild populations. Containment of wild American mink populations under the effects of possible migration from the fur farms could be especially problematic. With that issue in mind, we have used microsatellite analysis todetermine the genetic polymorphism in two color breeds of farm-bred American mink in the populations of several Belorussian model fur farms, as well as the same characteristics for the feral populations on the territories adjacent to said fur farms. We confirm the presence of effective influx of mink into the wild from fur farms, determined through the means of analyzing microsatellite genotype data of feral and farm populations.

Subcellular particles of Chlorella vulgaris C 111 IBCE C-19 were isolated by differential centrifugation in sucrose density gradient. It was stated for the first time, that these particles can cleave casein, gelatin, fibrinogen and hemoglobin at pH 7.4 and 9.0. Using group-specific proteinase inhibitors, a set of serine-, cysteine- and metalloproteinases was identified in this material. However, the detection of this set of proteolytic enzymes is only possible when several different proteins are used as substrates. In some cases, virtually all of the used arsenal of group-specific proteinase inhibitors proved to be little effective. This suggests that these are proteinases of a different nature than those listed above, which requires further perspective research.

Efficiency in detecting of tomato forms with no chalcone-naringenin flavonoid in pink-fruited and yellow-fruited forms was evaluated using DNA markers for various polymorphisms of the SlMYB12 gene. The closest relationship between a phenotype with the transparent skin of fruits and a deletion in the promoter region of the SlMYB12 gene was shown. The highest efficiency in the detection of the recessive y allele of the regulatory SlMYB12 gene, leading to the chalcone-naringenin synthesis disruption and skin transparency, was established by a combination of markers MYB12-603delaF1/603del-aR6 (Myb-603del aF1/R6) and MYB12-603del-aF1/603del-aR5 (Myb12 aF1/R5). Fruit coloration peculiarities were shown depending on a combination of the structural alleles of a carotenoid biosynthesis pathway and SlMYB12 gene alleles. A combination of this y allele with the alleles of the gene of the lycopene-β-cyclase beta (b) and old gold crimson (ogc ) allows selecting pink and raspberry forms respectively. In tomato accessions with yellow and orange fruits, the y allele provides pale shades of the main coloration determined by carotenoid biosynthesis genes (yellow flesh (r), tangerine (t), Beta (B)). The presence of SNP T → C of the SlMYB12 gene (171476848 position of chromosome 1) was identified in 80 % of accessions with the transparent skin of fruits of the evaluated collection. The effect of the recessive y allele of the SlMYB12 gene on an increase in the lycopene concentration of tomato fruits in a combination with b, ogc alleles was shown. Using MAC methods by fruit quality genes, including the SlMYB12 gene, the cherry tomato variety Malinovyj koktel with a high lycopene accumulation was developed and included in the State Register

The hepatoprotective properties of the silymarin and the plant alkaloid berberine combinationin experimental paracetamol-inducedliver damage were studied. Silymarin was obtained from milk thistle seeds. The conditions for extraction of flavonolignans (silymarin) were optimized. 70 % ethyl alcohol, ethyl acetate and water were used as extractants. It was shown that the optimal conditions for the extraction of flavonolignans in order to obtain the maximum yield of flavonolignans were alcohol extraction in a Soxhlet apparatus. The experiment showed that the combined of silymarin and berberine was greater than their individual actions, which most effectively permitted stabilization of hepatocyte membranes and prevented altering their integrity in paracetamol-induced toxic liver damage. The self-emulsifying system with silymarin and berberine to a greater extent a significant extent prevented dystrophic changes in hepatocytes and necrosis in liver tissue, reduced hyperfermentemia in rat blood serum, prevented disturbance in the activity of thioredoxin reductase and enzymes of the glutathione antioxidant system and there by more effectively prevented hepatocyte functional impairment.

Vitamin D deficiency is an important environmental risk factor that influences the prevalence and severity of several autoimmune diseases, including rheumatoid arthritis (RA). The aim of this study was to determine the incidence of vitamin D insufficiency and deficiency in patients with RA, to establish the relationship between serum vitamin D levels and indicators of disease activity. 156 patients with RA were included in the study, mean age 60.2 ± 13.9 years. Assessment of clinical status was performed, serum concentrations of rheumatoid factor (RF), C-reactive protein (CRP), total vitamin D (25(OH)D), antibodies to cyclic citrullinated peptide (ACCP) were determined. RA disease activity was evaluated using DAS28 (disease activity score), SDAI (Simplified Disease Activity Index) и CDAI (Clinical Disease Activity Index) scores. Average levels of 25(OH)D in the surveyed sample were 25.2 ± 13.2 ng/ml. The results of the study indicate a high prevalence of vitamin D deficiency in patients with RA. Normal indicators of vitamin D, its insufficiency and deficiency were observed in 47 (30.3 %), 45 (28.7 %) and 64 (40.7 %) patients, respectively. Low level of serum 25(OH)D was associated with higher indices of RA activity according to DAS28, SDAI and CDAI, as well as with greater tender joint count. Vitamin D should be prescribed as an adjunctive therapy in patients with active RA due to its potential immunomodulatory effect, as well as for the prevention and treatment of bone metabolism disorders.

The results of studying the process of obtaining complex-profile elements of the substrate of mirrors of optical telescopes from reaction-sintered silicon carbide ceramics are presented. It is shown that the strength of silicon carbide ceramics depends on the dispersion of the silicon carbide powder and on the temperature of reaction sintering. An increase in the sintering temperature from 1500 to 1650 °C leads to an increase in strength by 60 MPa, and to 1800 °C – to a decrease in strength by 40 MPa. An increase in strength is explained by a decrease in free silicon and an increase in the content of secondary silicon carbide, a decrease in strength is explained by an increase in the size of carbide grains. The study of the influence of the modes of soldering of hexagonal elements to obtain a complex-profile element of the substrate of the mirror of an optical telescope on the strength of the soldered seam showed that the introduction of silicon carbide powder 7 μm in size and amorphous boron in an amount of 6 % into the solder composition based on silicon carbide has a positive effect on the strength of the soldered seam. Tests of the brazed specimens at three-point bending showed that fracture occurs along the body of the specimens being brazed, and not the brazed seam. The structure of the brazed joint depends on the composition of the braze alloy and the gap between the samples to be brazed.

The analysis of the stages and stages of the design of technological equipment for traditional production, studied the features of the formation of technological equipment using flows of energy and consumables. Structural synthesis of mechatronic complexes in digitalized production allowed adding new stages to the process of creating technological equipment for both traditional automated subtractive and new additive manufacturing. The processes of manufacturing parts without shaping equipment described by the algorithms according to the proposed structural diagram of connections provide an opportunity to analyze existing and develop new equipment in laminate synthesis of products. It is shown, how in the design of technological equipments for their use in new additive and traditional subtractive manufacturing, methods and schemes of laminate synthesis and shaping of parts from composite materials are used, based on the use of various energy flows and material components, as well as methods and schemes of automation and computer product manufacturing process management.

Experiments of n-decane/air self-ignition at the temperature range 600–800 K were carried out by rapid compression machine. It allowed obtaining temperature-concentration limits of transition from single-stage to two-stage ignition. High-speed video recording has let established that hot stage ignition always initiates near the piston surface or quartz window. These locations depend on gas temperature. Combustion of the test mixture occurs in the entire volume after that. Couple sequential photos of cool flame shows that it starts same near piston surface and has a complicated volumetric structure caused by the roll-up gas vortex. It is shown that partial n-decane pressure increasing during compression causes the non-equilibrium condensation process near the inner surfaces of combustion chamber. This leads to significant redistribution of n-decane concentration and determines local characteristics self-ignition of n-decane/air mixture.

Six pig breeds: Belarusian large white, Belarusian meat, Belarusian black and white, landrace, Yorkshire and Duroc are involved in breeding and hydridization of pig breeding in Belarus. More than 85 % of pigs supplied to meat processing plants of the Republic are provided by different combinations of interbreed hydridization.

For the effective development of this branch in the Republic, the Scientific-Practical Center on Animal Husbandry of the National Academy of Sciences of Belarus organized the system of selection and breeding work in pig breeding directed to create new competitive breeds, types, and hydrides of pigs adapted to the industrial production conditions and not inferior to the productivity of the analogs of the world selection.

The main link of this system is the first-order breeding plants (nucleus units) as new-type plants dealing with the selection and breeding of the best animals with the outstanding genetically conditioned breeding and productive qualities. The second link of this system is the first-order breeding breeders that are completed with high-valuable breeding pigs from the leading nucleus unit and are engaged in their reproduction to obtain grandparents (GP).

Assessing the level of the technological development of pig breeding in Belarus during the period to the 2030 year, we predicted the indices for the all predictable years (2020–2030). The existing level of the technological development of the pig breeding branch is assessed as the mean one. During 2020–2021 the pig breeding level will be moderate-high, during 2022– 2023 – high, and since 2025–2030 – intensive.