Institute of Computational Modeling

Rapid, aqueous macrocyclization strategies that proceed in high conversion are valuable for ultra-large macrocyclic peptide library synthesis via display and DNA-encoded library (DEL) technology. Here we report an on-DNA macrocyclization based on sulfur(VI) fluoride exchange (SuFEx) that unites above features. This approach embeds a phenol and an aryl sulfonyl fluoride within a DNA-tagged peptide to accelerate SuFEx and trigger intramolecular cyclization immediately upon dissolution in basic aqueous buffer. Macrocycles ranging from 15-to 52-membered rings bearing diverse amino acids were synthesized efficiently. The reaction integrates seamlessly into DEL workflows and enabled discovery of potent, de novo macrocyclic RIPK1 inhibitors. The on-DNA cyclization conditions readily translate off-DNA to furnish sulfonate-and sulfonamide-linked macrocycles. NMR analyses showed SuFEx-derived biaryl linkers act as conformational elements: changes in aryl substitution and linker length tune backbone conformations from extended strands to rigid turns. These findings establish SuFEx cyclization as a robust, biocompatible strategy for programmable macrocycle design and drug discovery.

Owing to the fact that ultrathin platinum films have many practical applications, the information concerning the initial stage of the formation of these films raises considerable interest. The effect of the film thickness on the morphology, as well as on the electrical and optical properties, was experimentally studied by a combination of methods (TEM, SAED, SEM, AFM, optical spectrophotometry, and electrical resistance measurements). The growth mechanisms of the films with an average thickness from 0.2 to 20 nm were determined, which is equivalent to the thickness of 1 to 100 monolayers (ML). The percolation threshold was reached, with the average film thickness being ≈1.0 nm, when electrical conductivity appeared. With an average thickness of ≈2.0 nm, the platinum films became almost continuous. The obtained data were analyzed within the framework of scaling theory. The growth of the platinum films at the initial stage (0.2–2.0 nm) was shown to proceed in the mixed 2D/3D growth mode. Here, 3D nanoislands, having a crystalline structure, were formed simultaneously with the formation of an almost continuous 2D subnanometer layer possessing an amorphous-like structure.

As a model of shear rupture in the Earth’s crust at the depths of seismic activity, which grows with a velocity exceeding the velocity of longitudinal waves, we consider a Volterra edge dislocation moving in an infinite isotropic elastic medium under the action of preliminary tangential stresses. In the plane strain approximation, the equations of stationary motion of the medium around the dislocation are reduced to a hyperbolic system of equations for velocities and stresses, which is integrated by the method of characteristics. Using the invariant $$ J $$ –integral, an estimate of the energy released during the motion of dislocation is obtained, depending on the velocity, the value of tangential stress at infinity, the length of the fan adjacent to the vertex of dislocation, and on the nature of the distribution of the Burgers vector in the fan.

IT IAD Management of complex economic systems based on IAD methods and AI software using the example of the financial and economic state of the IT industry in the region Rutta Natalya Aleksandrovna, Sakharova Lyudmila Viktorovna....

Abstract Large‐scale patterns of the steady‐state magnetosheath plasma flow and their dependence on the interplanetary magnetic field (IMF) have been reconstructed for the first time on the basis of large multi‐year multi‐mission pool of spacecraft observations, concurrent interplanetary data, and an empirical high‐resolution model. The flow model architecture builds upon a recently developed magnetosheath magnetic field representation by flexible expansions of its toroidal and poloidal components in a coordinate system, naturally conformed with the magnetopause and bow shock shapes. The model includes two physics‐based flow symmetry modes: the first one treats the magnetosphere as an axisymmetric unmagnetized obstacle, whereas the second mode takes into account the geodipole tilt, an important factor in the reconnection effects. The spacecraft data pool includes 1‐min average data by Themis (2007–2024), Cluster (2001–2022), and MMS‐1 (2015–2024) missions, as well as OMNI interplanetary data. The model drivers include the solar wind particle flux, IMF components, and the geodipole tilt angle. The model calculations faithfully reproduce the average plasma flow geometry and substantial effects have been found of the IMF orientation and magnitude, a principal factor that defines electromagnetic forces inside the magnetosheath. A strong dependence of the magnetosheath flow patterns on the Earth's dipole tilt indicates an important contribution of reconnection effects at the magnetopause to the solar wind particle transport around the dayside magnetosphere.

Two-layer flows of liquid and vapor-gas mixture are studied on the basis of the three-dimensional Ostroumov-Birikh solution subject to the diffusion type of evaporation on a thermocapillary interface. The results of analytical and numerical simulation of convective flows in a channel with solid impermeable walls arising under different temperature conditions are presented. The values of the evaporation mass flow rate and thermocapillary stresses calculated on the basis of the exact solution and obtained experimentally are compared.

The use of geographic information technologies and digital elevation models (DEMs) enables significant automation of the process of analyzing the relief of the study area. Modern DEMs are based on remote sensing (RS) data, and their accuracy is constantly improved. The research was performed to analyze the possibility of using DEM for geomorphometric analysis of the relief of an agricultural area. A geomorphometric analysis of the relief of the agricultural territory of the experimental production farm Mikhailovskoe, Federal Research Centre Krasnoyarsk Science Center, Siberian Branch, Russian Academy of Sciences, was based on the new generation nonprofit Forest and Buildings removed Copernicus Digital Elevation Model (FABDEM) and the functionality of the geographic information system (GIS) toolkit SAGA GIS (System for Automated Geoscientific Analyses, Geographic Information System). A series of large-scale thematic maps of the farm has been compiled: of the steepness and aspect of slopes, of curvature (horizontal and vertical), of terrain ruggedness index (TRI), of the index of planar erosion potential (LS-factor), of topographic wetness index (TWI), etc. A model of surface runoff has been obtained. Despite the small area, the surface structure of the territory of the Mikhailovskoe farm is heterogeneous, including 85% of plain areas (flat surface) and 15% of local elevated landforms. Slopes to 3° steep account for 92% of the total area; and plots on slopes steeper than 3° occupy only 8%. The farm fields are dominated by areas with western and eastern slopes (42%), southern slopes account for 36%, and northern slopes occupy 22% of the total area. The results of the analysis of the TWI of the farm area testify to insignificant erosion danger: 0.5% of the total area of the farm are occupied by plots with drainage depressions and 3% are represented by hills. According to the index of planar erosion potential, plots on hills are located on slopes more than 4° steep.

The phenomenon of concentration polarization (CP) in membrane systems refers to the emergence of concentration gradients in solution near the membrane surface due to the selective transport of some solution components through the membrane under the effect of transmembrane driving forces. CP accompanies all types of membrane processes, changing transport conditions and reducing efficiency of separation processes: in most cases, the total transport rate decreases, the energy consumption increases, and the selectivity of the transport process is lost. This review addresses general regularities and specific features of the CP phenomenon in electrodialysis, reverse osmosis, nanofiltration, ultrafiltration, and pervaporation processes, as well as membrane sensing systems and fuel cells. Fundamentals of the CP phenomenon and experimental methods for its investigation are discussed.