Compact finite difference schemes of approximation orders 4 + 1 and 4 + 2, constructed on minimal stencils, are presented and investigated for the one-dimensional non-stationary quasilinear heat equation, and do not require an iterative process for their implementation. The computational efficiency is achieved by parallelizing the Thomas algorithm over even and odd grid nodes. The monotonicity conditions are obtained and two-sided estimates of the difference solution and a priori estimates in the uniform norm are proved. Computational experiments are also presented to illustrate the effectiveness of the proposed methods, as well as their convergence with the corresponding order.

In this paper, a comparative analysis of the performance of AutoDock Vina, NNScore2, RF-Score-4, CENsible, HGScore, OnionNet-2, PIGNet2, and PLANET scoring functions designed to predict the binding affinity of small molecules to a target protein based on molecular docking data was made using the CASF-2016 benchmark dataset. The study has shown that the deep learning scoring functions PLANET and OnionNet-2 demonstrate the highest accuracy, effectively predicting the affinity of the ligand to the molecular target and increasing the reliability of identifying compound candidates with high potential for inhibitory activity. The obtained data indicate that both PLANET and OnionNet-2 can be used in computational protocols of molecular docking for subsequent calculation of the exponential consensus rank for each ligand and reliable selection of the most probable inhibitors of a given therapeutic target.

Using the numerical solution of the Maxwell–Bloch equations, we study the interaction of short light pulses with resonant amplifying media. We consider pulses of various shapes – with Gaussian, rectangular, and exponential envelopes, the latter of which has recently attracted increased attention due to its potential for implementing new effects such as virtual absorption. We show that by choosing the shape and duration of the incident pulses, we can control the intensity and time of the amplified radiation generation, as well as the population dynamics of the medium levels.

The currently used radial distribution functions (pair correlation of particles) are time- and space-averaged quantities, and reconstructing the size and structure of individual molecular groups of liquids from them cannot be solved unambiguously. In the article, using liquid water under normal conditions as an example, it is shown that its structure is best represented by the instantaneous spatial distribution of oxygen atoms over distances. This distribution was calculated from the structure of a water cluster (H2O)56 without taking into account molecules subject to the edge effect. The cluster structure was calculated by the nonempirical quantum chemical method in the HF LCAO approximation with the 6-31G basis set. The data on the exact positions of each oxygen atom of several molecules located near the cluster center were selected as the origin of coordinates for calculating the radial distribution function g(r) in the usual way. The shape of g(r) strongly depends on the integration step. With a minimum integration step of 0,1 Å at r < 5.6 Å, it has 10 peaks, the number of which decreases to three with its increase. In this case, the g(r) diagram acquires a normal form, and information about its fine structure is lost. The most reliable and visual interpretation can be obtained by jointly analyzing the radial distribution diagram of the number density of particles and the spatial distribution of particles by distances.

The adsorption of Ni2+ ions by sorbents based on dolomite thermally activated at 800 °C (D-800), phosphated dolomite (PD), and Zr-modified PD (PD-Zr) was studied. It was found that D-800 sample was characterized by the highest sorption capacity (364 mg/g), while at the initial concentration of Ni2+ ions of 300 mg/L, the purification of aqueous solutions to the MPC standards for drinking water (< 0.1 mg/L) was achieved, and at C0 (Ni2+) of 50 mg/L, deep purification to a residual concentration of < 0.01 mg/L occurred. It was revealed that the absorption of Ni2+ ions by the D-800 sorbent is due to the heterogeneous precipitation of nickel hydroxicarbonate, and in the case of the PD sorbent, nickel hydrophosphate is formed. The results of desorption of Ni2+ ions from saturated sorbents indicated the occurrence of ion exchange with the participation of amorphous zirconium phosphate for the PD-Zr sample. The lowest desorption degree (<1 %) was demonstrated by samples D-800 and PD. In the dynamic sorption process, the granular sorbent D-800 provided purification of more than 1000 column volumes of solution with C 0 (Ni2+) 10 mg/L below the MPC standards for drinking water at a linear filtration rate of 20 m/h.

The dynamics of R1 and PR1 gene expression in leaves of potato (Solanum tuberosum L.) highly resistant cultivar Vectar and susceptible to late blight cultivar Uladar under normal conditions and after 3-day infection with Phytophthora infestans (Mont.) de Bary was studied. In the absence of infection, the expression of R1 was detected in the leaves of the Vectar, which was slightly increased after infection of leaves with late blight. In the susceptible Uladar R1 expression was not detected in either healthy or infected leaves. PR1 expression in the Vectar was present in the cells of uninfected leaves and increased during infection. The Uladar was characterized by a significantly lower level of PR1 expression in uninfected and infected leaves as compared to Vectar, but activation of PR1 expression in response to the pathogen attack was more significant in the Uladar than in the Vectar. The exogenous ethylene donor ethephon has a stimulating effect on expression of R1 in the Vectar and expression of PR1 in both cultivars. Exogenous salicylic acid has a significant positive effect on the expression of R1 and PR1 in the Vectar, but inhibited the accumulation of PR1 transcripts in the Uladar. The synthetic brassinosteroid epin has an inhibitory effect on the transcription of R1 and PR1 in both cultivars. The obtained data reflect general and cultivar-specific patterns in defense responses at the level of relative expression of the studied genes. The obtained expression profiles of the R1 and PR1 genes in potato varieties sensitive and resistant to the action of phytopathogenic microflora, against the background of the simultaneous action of phytohormones, can become the basis for an early assessment of the sensitivity of breeding potato varieties to the action of the specified microflora.

The effect of pharmacological and toxic concentrations of lithium salts (sulfate and chloride) on the expression and functional activity of the transporter protein P-glycoprotein (P-gp) in human lymphocytes in vitro was studied. It was found that in lymphocytes exposed to both lithium chloride and sulfate in the concentration range from 3 to 10 mM, inhibition of the functional activity of the membrane transporter P-gp occurs, and this effect depended on both the specific type of salt and its exposure concentration. A multidirectional effect on P-gp expression was found (an increase when cells were exposed to 10 mM lithium sulfate and no changes at the same concentration of lithium chloride), indicating the possible involvement of specific signaling pathways that are activated or inhibited depending on the anion, and not just the lithium cation. The results obtained are planned to be used in the future to create a method for assessing lithium toxicity for monitoring lithium concentrations in the blood.

This study presents the results of an investigation into the structure and physico-mechanical properties of an absorbent wound dressing containing silver and copper, produced in the Republic of Belarus. The density of the silver- and copper-containing dressing was 12.6 % higher than that of the control cellulose-based wound dressings. It was found that after 48 hours of use on pediatric burn wounds during the first phase of the wound process, the density of the silver- and copper-containing dressings decreased by 28.3 % (p < 0.001). Concurrently, the copper concentration within the dressing volume decreased by 22.9 % (p < 0.001), and the silver concentration decreased by 82.1 % (p < 0.001). The coefficient of dynamic friction of the used silver- and copper-containing dressing increased by 4.1 %, indicating the low-adherence (atraumatic) properties of this medical device during clinical use. Furthermore, the application of the silver and copper additive increased the tearing force of the wound dressing to 47.74 N, which subsequently decreased to 11.78 N after use.

The present work is devoted to the study of the influence of a compatibilizing agent based on functionalized polyethylene grade PF-1, developed and produced at the MPRI of NAS of Belarus, on the formation of the structure, fireretardant properties and mechanical characteristics of high-density polyethylene (HDPE) containing a nitrogen-phosphorus flame retardant (NPFR). Using IR spectroscopy, the formation of interfacial interactions between PF-1 and NPFR was established, which causes an increase in the compatibility of components in the HDPE matrix. Analysis of micrographs obtained by scanning electron microscopy (SEM) showed that the introduction of PF-1 into the HDPE/NPFR composite leads to a significant modification of the morphology, characterized by a decrease in the average particle size of the dispersed NPFR and an improvement in the adhesion between the NPFR particles and the polymer matrix. Differential scanning calorimetry revealed a decrease in the enthalpies of melting and crystallization of the HDPE/PF-1/NPFR composite, indicating an increase in the interfacial interaction of the components. It was shown that the flame-retardant HDPE composition containing NPFR together with PF-1 has a reduced combustion rate, which is due to a more uniform distribution of the flame retardant in the polymer matrix. The results of the mechanical tests indicate an increase in the tensile modulus and yield strength for the HDPE/NPFR composite with the addition of the PF-1 compatibilizer.

Based on crystal-chemical and physicochemical analysis of the diamond formation, topological transformation was carried out diagram models states carbon. A phase diagram of metastable transformations is proposed, with consideration given to the energy absorbed by dissipative structures. The diagram defines the positions of the lines describing phase transitions, their number, increasing as a result of the formation of transition structures, depending on the temperature, pressure and amount of absorbed energy. The diagram highlights new areas of phase formation during the formation of natural minerals, including impact diamonds with lonsdaleite, transition areas of precipitation from the liquid of ultradispersed diamond particles and microgroups of graphite and lonsdaleite. The carbon phase diagram identified grains of highpressure carbon phases of the Popigai deposit – impact diamonds formed during the collision of a meteorite with graphitecontaining rocks. Relatively transparent, large superhard grains of the mineral are impact diamond-lonsdaleite abrasive. Virtually opaque, dark grains of the mineral, formed during impact with shear, are sprouts of ultra-dispersed diamond particles with microgroups of graphite and lonsdaleite.