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The discovery in higher animals of proteins from the Ly6/uPAR family, which have structural homology with snake “three-finger” neurotoxins, has generated great interest in these molecules and their role in the functioning of the organism. These proteins have been found in the nervous, immune, endocrine, and reproductive systems of mammals. There are two types of the Ly6/uPAR proteins: those associated with the cell membrane by GPI-anchor and secreted ones. For some of them (Lynx1, SLURP-1, SLURP-2, Lypd6), as well as for snake α-neurotoxins, the target of action is nico- tinic acetylcholine receptors, which are widely represented in the central and peripheral nervous systems, and in many other tissues, including epithelial cells and the immune system. However, the targets of most proteins from the Ly6/uPAR family and the mechanism of their action remain unknown. This review presents data on the structural and functional properties of the Ly6/uPAR proteins, which reveal a variety of functions within a single structural motif.

This study proposes a new approach for analyzing images of the internal structure of soil (microtomograms) and modeling key hydrophysical functions based on the tomographic characteristics of the pore space. The approach is based on constructing a series of closed shells (α-shapes) around the studied three-dimensional section of the tomogram. These shells are capable of penetrating into the pores of the object with a diameter greater than a specified value. The dependence of the internal volume of the shells on the minimum pore size is analyzed. The algorithm of α-shapes construction simulates the process of drying pores connected to the surface and allows for analyzing the anisotropy of pore connectivity by limiting the permeability of a part of the object’s surface. The constructed α-shapes model the surface of the liquid phase, and the maximum curvature of the surface corresponds to the capillary pressure. The approach is applied to analyze samples of the soil microprofile of a crusty solonetz with a contrasting pore space structure. The microhorizons of the solonetz demonstrate pronounced closed porosity and anisotropy of pore connectivity. The approach allows for the assessment of connectivity and anisotropy of pores, the water retention curve (WRC) without considering soil shrinkage. The results were compared with typical known WRCs of solonetzic soil horizons in soils of Russia. A comparison of WRC models obtained based on 2D and 3D images was conducted. The method was also tested on tomograms of samples of aeolian laminated sandstone, for which both tomograms and direct WRC measurements were simultaneously available.

— Particle size distribution (PSD) of a significant number of soil samples of various geneses from the Komi Republic was studied by the Kachinskii method (KM). Calculated, procedural, random, and systematic factors influencing the precision and correctness of measurement results performed with the KM protocol are considered. The influence of sample preparation (the degree of grinding of soil samples) and procedures for measuring the mass fraction of elementary soil particles (ESPs) on the quality of the results of studying soil PSD was assessed. The instability of measuring the mass of fine sand (0.05–0.25 mm) and coarse silt (0.01–0.05 mm) fractions with the KM protocol was shown. The dependence of the uncertainty of measurement results caused by random factors on the mass fraction of ESPs of particular size fractions is noted: the lower the mass of ESPs in the fraction, the higher the uncertainty of the measurement results. A modification of the Kachinskii method (KM) has been developed to improve the quality of soil PSD analysis. It includes: (1) separation of fine sand particles using a sieve with a mesh size of 0.05 mm (instead of calculating this fraction by difference according to the MK protocol); (2) use of scales of the first class of accuracy to measure the mass fraction of silt and clay particles; (3) control of the PSD research based on the summation of the measured values of the mass fraction of ESPs of six fractions and acid-soluble compounds (losses from HCl treatment). The standard for operational control of the mass fraction of the sum of ESPs after dividing them into fractions is 100 ± 5%. A metrological study of the Kachinskii method and its modifications was carried out. The proposed modification of Kachinskii`s method made it possible to reduce the uncertainty in the measurement results of the mass fraction of ESPs of small fractions (ω n < 10%) and shift the lower limit of measurements to 1%.

This paper establishes the concept of developing dynamic digital twins of soils. These digital twins are envisioned as a key component of the biosphere and a fundamental element for sustainable agricultural production. Further development in this area is essential to ensure Russia’s technological independence and to facilitate the structural adaptation of its economy to current unprecedented challenges. The current state and role of soil digital twins within the conceptual framework of agricultural digital transformation are examined. Finally, the creation of a standardized approach for formally describing applied problems and data related to soil digital twins has enabled the development of a methodology for constructing data structures and architectures for these digital twins in agricultural landscapes on the basis of standards for soil data integration and mathematical models.

We present the first record of Holocene fossil insect assemblages from Central Yakutia. A stratigraphic sequence in the locality within the Vilyuy River valley is a buried oxbow. The late Holocene water body inherited an impervious stratum from the late Pleistocene. The organic layer preserved rich fossil assemblages of macrofossils including insects and other invertebrates, plants, and charcoal. The ancient flora and fauna include species that are common in Yakutia as well as those that are rare and absent in the region. The most abundant finds are leech cocoons and bogbean seeds. The macrofossils of some insects were found along with remains of their host plants. Despite the absence of intensive human land use in the area, traces of fires were recorded. The oxbow represents the environment of a floodplain wetland that developed separately from the ecosystem of the adjacent sand dunes.

The U–Th/He method has been applied for the first time to determine the age of epigenetic pyrite from the oil source rocks of the Bazhenov Formation, Western Siberia. The possibility to date the post-sedimentation processes in a sedimentary basin by authigenic pyrite using the U–Th/He method is shown. The U–Th/He isochrone age of pyrite ( n = 7) from the dolomites of the Bazhenov Formation within the Frolovskaya megadepression is much younger than the sedimentation age and corresponds to the Santonian–Cenomanian stages of the Upper Cretaceous (90 ± 8 Ma).

An Erratum to this paper has been published: https://doi.org/10.1134/S1028334X23060181

The results of the studies performed at the Shubnikov Institute of Crystallography and devoted to the development of UV optical filters based on complex nickel and cobalt compounds are reviewed. The structural dependence of the optical properties of these crystals and their thermal stability is discussed. The fundamental features of mixed crystals grown from solution and developed approaches to the design of optical filters based on structurally perfect mixed K 2 (Co,Ni)(SO 4 ) 2 ⋅6H 2 O crystals are described. The possibility of designing UV- А optical filters by partial substitution of the ligand environment of transition metal ions is demonstrated.

Mixed crystals of potassium‒cobalt sulfate hexahydrate/potassium‒nickel sulfate hexahydrate (K 2 Co(SO 4 ) 2 · 6H 2 O/K 2 Ni(SO 4 ) 2 · 6H 2 O (KCNSH)) have been grown from a solution with an isomorphic-component ratio of KCSH : KNSH = 1 : 2. The presence of mosaic microheterogeneity in KCNSH crystals at a level of ∼2 at % is confirmed, and its dependence on supercooling is studied. The radial heterogeneity of KCNSH crystals is investigated as a function of the growth direction and rate. The heterogeneity of Co concentration in different samples is shown to vary from 0.2 to 0.8 wt %.

The results of photographic observations of Jupiter’s Galilean satellites made with the 26-inch refractor at the Pulkovo Observatory from 1986 to 2005 are given. Satellite coordinates with respect to Jupiter and the mutual distances between the satellites have been determined. A scale-trale technique that does not require reference stars for the astrometric reduction of measurements has been used. The effect of the Jupiter phase has been taken into account in the jovicentric coordinates. The observation results have been compared with a modern theory of the Galilean satellites’ motions. Systematic observation errors depending on the observation technique have been studied. The intrinsic observation accuracy in the random quotient is characterized by the values 0.041″ over X and Y . The external accuracy of the relative Galilean satellite coordinates determined by comparing the observations with modern ephemerides turned out to be equal to 0.165″, 0.213″ for the Jovicentric coordinates and 0.134″, 0.170″ for the “satellite-satellite” coordinates. The highest accuracy of the relative satellite coordinates is reached at small distances between the satellites which are less than 100″: the corresponding mean-square errors of one observation are equal in to the external convergence to 0.050″, 0.070″. The results of photographic observations have been compared with the first CCD observations of the Jupiter satellites made in 2004 with the 26-inch refractor.