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The new mineral zvěstovite-(Fe), ideally Ag6(Ag4Fe2)As4S13, has been found in the small abandoned Ulatayskoe Ag–Cu–Co occurrence, Ovyurskiy District, Tuva Republic, eastern Siberia, Russia. It occurs as anhedral grains, up to 1 × 0.4 mm in size but usually much smaller, closely intergrown with native silver, in Mg-bearing siderite–quartz gangue. Other associated minerals include acanthite, cobaltite, As-rich members of the tetrahedrite group (kenoargentotennantite-(Fe), tennantite-(Zn), zvěstovite-(Zn)), gersdorffite, jalpaite, krutovite, löllingite, pearceite, safflorite, skutterudite, Br-bearing chlorargyrite, malachite, and muscovite. Zvěstovite-(Fe) is iron black and opaque and has a black streak and metallic lustre. It is brittle and has a conchoidal fracture. No cleavage or parting is observed. The Vickers micro-indentation hardness (Vickers hardness number, VHN; 25 g load) is 169 kg mm−2 (range of 149–187 kg mm−2, n=4), corresponding to a Mohs hardness of 3–3.5. The calculated density is 4.979 g cm−3. In reflected light, zvěstovite-(Fe) is light grey with a greenish tint and isotropic. Internal reflections are ubiquitous and deep red in colour. The reflectance values for wavelengths recommended by the Commission on Ore Mineralogy of the International Mineralogical Association are (R, %): 32.5 (470 nm), 31.1 (546 nm), 30.1 (589 nm), and 28.8 (650 nm). The chemical composition (wt %, electron microprobe data, mean of eight spot analyses) is as follows: Cu 1.81, Ag 56.02, Fe 4.60, Zn 0.01, As 13.85, Sb 2.63, S 21.50, total 100.42. The empirical formula, calculated on the basis of 16 atoms per formula unit, is Ag9.93Cu0.54Fe1.58As3.54Sb0.41S12.83. Zvěstovite-(Fe) is cubic and has a space group of I4‾3m, with a=10.8601(3), V=1280.86(11) Å3, and Z=2. The strongest lines of the X-ray powder diffraction pattern (d, Å (I, %) hkl) are 7.68 (11) 110, 3.136 (100) 222, 2.717 (12) 400, 1.984 (8) 521, 1.921 (23) 440, and 1.638 (11) 622. The crystal structure of zvěstovite-(Fe) was refined to R1=0.0551 for 400 unique reflections with Fo>4σ (Fo). The possible ordering of the split M(2) sites is discussed. The new mineral is the Fe isotype of zvěstovite-(Zn). Both these minerals form the zvěstovite series within the tetrahedrite group.

Objective. Investigation of the influence of the design scheme on the dynamic characteristics of the frame of a building of complex shape in plan.Method. Four variants of structural solutions for the frame of a complex-shaped building have been developed and four spatial finite element models have been built in the Lira-SAPR software package. The final elements are assigned design materials and sections. The models take into account loads and impacts in accordance with the current regulatory documentation for the selected construction area. The ground base is taken into account according to the one-parameter Winkler model.Results. Dynamic calculation of the developed models of the building frame was performed, frequencies, forms of natural oscillations, acceleration of the upper floor were obtained. The results obtained were compared with the regulatory requirements, their impact on the cost-effectiveness of the design solutions of the building under study was considered.Conclusion. The analysis of the dynamic calculation results showed that the use of several design options makes it possible to choose the most economical version of the building frame. Also, as a result of the study, it was found that cutting the frame of a complex shape in terms of simple blocks is not always effective from the point of view of optimizing dynamic characteristics.

Improving the standards of collecting and maintaining valuable genetic resources accessions and information about them is currently of crucial importance for the successful development of the world viticulture in the light of the challenges caused by the spread of grape diseases and climate change. This review briefly characterizes the global grapevine gene pool, approaches to its conservation, including base and duplicate conservation techniques, and the current status and prospects of the progress in in vitro and cryogenic preservation methods. The genetic potential of grape wild relatives is assessed focusing on particular species as sources of resistance genes to biotic and abiotic stressors. Achievements in the application of gene editing technologies to increase grape resistance to diseases are discussed. It is noted that a common practice at this stage is to knock out the genes responsible for grapevine susceptibility to diseases, whereas a more advantageous approach in the future will be to make targeted changes in the grape genome based on the knowledge of resistance genes in its wild relatives. Therefore, grape wild relatives need to be studied thoroughly using modern methods of forward and reverse genetics. Regarding the issues of grape genetic diversity conservation and expansion at the current technological stage, the status and significance of the plant germplasm and herbarium (WIR) collections held by VIR are scrutinized in detail. Authentication of grape germplasm accessions is marked as important, along with the role of the WIR herbarium, a unique collection incorporating physical carriers of reference genetic information on the national grapevine gene pool. Promising trends in the development of the WIR herbarium are outlined in connection with the establishment and preservation of nomenclature standards for domestic grape cultivars.

Objective. Solving the issues of reliability, durability and efficiency of buildings and structures is inextricably linked with the behavior of soils in their foundations. In order to establish a more realistic behavior of soils, the paper considers the determination of their stressstrain state, taking into account new factors, including physical influences, in particular, humidity.Method. Representing the structure of the soil in the form of a model composed of two elastic and one viscous elements, and assuming that the properties of the elastic elements do not change with changes in humidity, mathematical modeling of moisture stresses in the soil half-space was performed. The expediency of this model is explained by the fact that the transition to overly complicated material structure schemes introduces few significant corrections into the deformation laws and leads to serious calculation difficulties.Result. Replacing true time with conditional time leads to a significant simplification of the solution of the equation, since it reduces one part of it to a differential linear operator with constant coefficients. In this case, the opposite part can usually be considered as a given function of conditional time. The maximum value of stresses was obtained at full soil moisture, very low moisture intensity and very intensive moisture.Conclusion. By setting the appropriate moisture intensity, you can get the maximum stress that does not exceed the specified allowable value.

Objective. The article substantiates the need for digital simulation of emergency impact in the study of the stability of a building to progressive collapse by creating a simulator of local destruction.Method. To ensure the unique architectural appearance of the projected multifunctional high-rise complex, a complex shape has been developed with recesses in which elevator shafts are located. The principle of control of the structure due to the influx of external energy is observed. Energy conversion and the necessary protection is provided by the presence in the spatial frame of the building of balancing connections near architectural recesses, which allow stabilizing the state of a complex system. The spatial rigidity of the structural scheme of a high-rise building is ensured by the use of symmetrically located diaphragms and stiffening cores, rigid nodes for interfacing with the supporting structures of outrigger systems.Result. The calculation algorithm for progressive collapse includes the calculation of the stress-strain state of the building frame elements during normal operation. An analogue of the emergency action is created by excluding from the design model the bearing element, the instantaneous removal of which is modeled by a force with the opposite sign, determined by the results of the calculation in the normal operation stage.Conclusion. The stress-strain state of the frame, which occurs during local destruction, is a criterion for resistance to progressive collapse. The question of the need and the established form of outrigger floors in relation to a specific building has been investigated. The dependence of the dynamic characteristics when changing the structural solutions of the frame of a unique building is given.

The evolution of math Olympiad training for school students in Russia since the second half of the 20th century is analyzed in this article in the context of sociocultural transformations and changes in the post-industrial society’s didactic knowledge. A retrospective analysis of a large body of empirical data (organization charts and content of the All-Union and All-Russia Mathematical Olympiads for school students in 1974–2021 and the International Mathematical Olympiads in 1994–2020) reveals trends in the development of the mathematical Olympiad movement, in particular changes in the network infrastructure of mathematical Olympiads, objectives and content of Olympiad problems, Olympiad material design practices, and value-and-meaning orientations of math Olympiads. Accordingly, new approaches are proposed to prepare school students for math competitions. Analysis of changes allows substantiating the insufficiency of the “cognitive-reproductive” method of school student training widely applied both in Russia and beyond, which is based on a thematic principle of selecting problems by content and demonstrating examples of their solving to students. This method does not conform to the objectives of contemporary math competitions. Today, it is important to find and recognize the potential for mathematical creativity in solving problems within multidisciplinary professional spheres. The goal of modern Olympiad training is not only to teach school students a system of problem-solving procedures but also to promote their ability to identify the semantic structure of problems in order to pick adequate solving strategies. The assumption that Olympiad math problems can be classified by the logic of their solutions is supported by a relevant taxonomy of Olympiad math problem solving techniques.

A new mineral, hanauerite, ideally AgHgSI, was found in the oxidation zone of Ag- and Hg-bearing ores at two old, abandoned mines in Rhineland-Palatinate, Germany. In a holotype specimen originating from the Schöne Aussicht Mine, Dernbach, Westerwald, it is associated with plumbogummite–hinsdalite series of minerals and goethite. In cotype from the Friedrichssegen Mine, Bad Ems, it is associated with perroudite, goethite, and quartz. At both localities, hanauerite occurs as a prismatic crystal up to 0.15 mm long and up to 0.02 mm thick. The mineral is yellow, transparent, with an adamantine lustre. It is brittle, and cleavage was not observed. The calculated density values are 6.671 and 6.575 g cm−3 for holotype and cotype, respectively. The empirical formulae calculated (from electron microprobe data) based on the sum of all atoms = 4 apfu are Ag0.95Hg1.00S1.01(I0.83Br0.19Cl0.03)Σ1.05 for holotype and Ag0.97Hg0.97S1.05(I0.76Br0.25)Σ1.01 for cotype. Hanauerite is orthorhombic, space group Pmma; the unit cell parameters (from single-crystal X-ray diffraction data; holotype/cotype) are: a = 9.932(2)/9.9256(8), b = 4.6219(19)/4.6209(2), c = 9.891(4)/9.9006(4) Å, V = 454.0(3)/454.19(5) Å3, and Z = 4. The crystal structure was studied on single crystals extracted from both holotype and cotype specimens; R1 = 0.0416 (holotype) and =0.0544 (cotype). In hanauerite, Hg2+ cations centre strongly distorted octahedra with two short Hg–S bonds (Hg and S atoms build “crankshaft-type” chains) and four strongly elongated Hg–I bonds. The Hg-centred octahedra are connected via common edges and faces to form corrugated layers; Ag+ cations are located between these layers. Hanauerite is named in honour of the German mineral collector Dr. Alfred Hanauer (1912–1988). The common crystal chemical features of mercury sulphohalide minerals are discussed.

The article considers information modeling an emergency impact in the study of the stability of a digital architecture building to progressive collapse with the help of a local destruction simulator using the finite element method. A non-linear processor was used, the calculations were performed by the step-iterative method with automatic step selection. When calculating a digital architecture building for progressive collapse, a technique in a quasi-static formulation was used. Measures were developed to effectively counter the emergency. Since the placement of stiffness floors in the current regulatory documentation is advisory in nature, the need to install outrigger floors in relation to a digital architecture building was studied. The concept of a building of digital architecture of a complex shape in the plan was developed. To determine the most loaded rod element of the calculation model, the calculation of the frame of a unique building was performed at the stage of normal operation. At the 2nd stage, this element was switched off from work, and a computational model was obtained for simulating an emergency. As a result of a series of numerical experiments, taking into account various scenarios of emergency impact on the frame of a digital architecture building, a constructive scheme of a unique building with outrigger floors was developed. The unique building resulting from shaping will have a low weight skeleton, taking into account the use of innovative materials. The collaboration of digital technologies and innovative materials will allow the construction industry to move to a completely new level of development.

The article studies the operation of building frame structures with outrigger floors, taking into account seismic effects. The object of the study is a monolithic reinforced concrete frame of the building. The studies were carried out using the modern Lira SAPR software package, which implements the finite element method. Dynamic calculations were performed for several models with different design solutions for outrigger systems and their location. The study of the effectiveness of the decisions made was carried out based on the results of the spectrum of frequencies and periods of natural oscillations. Based on the results of dynamic calculations, two constructive solutions were chosen with higher frequencies and shorter oscillation periods compared to the original model. A study was made of the effect of outrigger floors on the stress-strain state of the building frame. Based on the results of the calculation, conclusions are drawn and recommendations are given for the design of earthquake-resistant buildings.

The behavior of soils in the foundations of buildings and structures, as well as in ground structures and massifs, is formed under the influence of force (surface and volume) and physical (temperature, humidity, etc.) influences. However, if mathematical modeling of force impacts in ground environments can be considered a completely solvable task today, then we consider such a statement premature in relation to physical impacts. The peculiarity of physical impacts is that they can be both the cause of forced deformations and the cause of changes in soil properties. The ground environment with creep properties, which is under both force and physical influences, is considered. The systems of equations of mechanics of a deformable solid for a triaxial stress state and a differential equation of thermal conductivity are used. Within the framework of the model of a linearly deformable continuous isotropic body, mathematical modeling of physical impacts in ground media with creep properties was performed. In a quasi-elastic formulation, a solution is obtained for an unlimited soil massif with a flat surface under the action of a plane -parallel heat flow. In the absence of force influences in a quasielastic medium for deformations from physical influences, we have the usual equations of elasticity theory. The solution obtained for an unlimited soil massif allows the calculation of stresses taking into account creep caused by temperature fluctuations on the surface in it.

The immune North American grapevine species Vitis rotundifolia Michaux (subgen. Muscadinia Planch.) is regarded as a potential donor of disease resistance genes, withstanding such dangerous diseases of grapes as powdery and downy mildews. The cultivar ‘Dixie’ is the only representative of this species preserved ex situ in Russia: it is maintained by the N.I. Vavilov All-Russian Institute of Plant Genetic Resources (VIR) in the orchards of its branch, Krymsk Experiment Breeding Station. Third-generation sequencing on the MinION platform was performed to obtain information on the primary structure of the cultivar’s genomic DNA, employing also the results of Illumina sequencing available in databases. A detailed description of the technique with modifications at various stages is presented, as it was used for grapevine genome sequencing and whole-genome sequence assembly. The modified technique included the main stages of the original protocol recommended by the MinION producer: 1) DNA extraction; 2) preparation of libraries for sequencing; 3) MinION sequencing and bioinformatic data processing; 4) de novo whole-genome sequence assembly using only MinION data or hybrid assembly (MinION+Illumina data); and 5) functional annotation of the whole-genome assembly. Stage 4 included not only de novo sequencing, but also the analysis of the available bioinformatic data, thus minimizing errors and increasing precision during the assembly of the studied genome. The DNA isolated from the leaves of cv. ‘Dixie’ was sequenced using two MinION flow cells (R9.4.1).

Background. VIR’s potato collection is one of the oldest and richest; however, it is constantly exposed to viruses that negatively affect useful agronomic properties of tubers. Close monitoring of the phytosanitary state of potato accessions helps to select the most effective method of therapy for subsequent healing of infected plants and obtaining high-quality planting material.Materials and methods. The research was aimed at improving the health of 18 varieties of Solanum tuberosum L. from the VIR collection. Testing for the presence of viruses was based on the ICA and RTPCR techniques, and the consequent healing was performed using the methods of meristem culture and cryotherapy.Results and conclusions. During the field test of potato plants, PVX, PVS and PVA were found to be the most common viruses. PSTVd was completely absent in all tested accessions. The effectiveness of in vitro healing of potato plants from viruses was assesses using meristem culture. The percentage of healed plants was 0% for PVS, 0% for PVX, 33.4% for PVA, 50% for PLRV, 72.3% for PVY, and 83.4% for PVM. Healing with meristem culture was shown to be the most effective against PVY and PVM. While assessing the effectiveness of post-cryogenic restoration of potato microplants, the level of post-cryogenic regeneration of the shoot tips in potato microplants was determined at 22.3% on average for a sample. The minimum was observed in k-16762 ‘Sagita N’ (5%), and the maximum in k-1378 ‘Marta’ (41.7%). Analysis of the effectiveness of potato recovery from viruses by in vitro cryotherapy showed that the percentage of recovered plants was 100% for PVY, 100% for PVA, 88.9% for PVM, 77.8% for PVS, 44.4% for PVX. Thus, the techniques of apical meristem culture and cryotherapy proved to be effective against PVY, PVA and PVM viruses. However, in the case of multiple infections, it is necessary to combine elements of different healing protocols to increase the effectiveness of the healing procedure.

Objective. Determination of the stress state of a ground base with a trapezoidal cutoff from the action of own weight, according to the conditions of equivalence of effects, is reduced to determining the stress state from the external surface load distributed according to the hydrostatic law. Methods. The problem of determining the stresses in the structure foundations at any degree of areas development of a plastic strain of the soil has a strict mathematical formulation, and similarity criteria can be obtained using a simpler construct of similarity theory. The simulation is performed by using similarity criteria based on which the model is executed, the loading conditions are determined, and the transition from the values measured on the model to the corresponding values of the full-scale structure is carried out. Similarity criteria can be obtained either with the help of similarity theory or with the help of dimensional analysis. An even greater effect of increasing the self-weight of a model made of transparent optically sensitive material can be achieved using the immersion method in conjunction with the centrifugal modeling method. If necessary, the stresses in the model area are fixed using the "freeze" method. Result. Using the equations system of the mixed problem of the elasticity and plasticity theory, and the scale method, similarity criteria are established for modeling stresses in the foundations of buildings and structures. Limitations on the choice of similarity multipliers for loose soils, the possibility of using the method of centrifugal modeling, as well as features of modeling connected soils are noted. Conclusion. A necessary condition for the similarity of the stress states of loose homogeneous bases in nature and the model is the equality of the similarity multipliers of the geometric scale and the force factor.

Intraspecific diversity of the immune grape Muscadinia rotundifolia Michaux. can serve as a rich source of valuable resistance loci to the most widespread pathogens and pests of grapevine. While only one Run1/Rpg1 resistance locus has been introgressed from M. rotundifolia to the Vitis vinifera gene pool, a number of other genes conferring resistance to powdery mildew and downy mildew have been identified in various Muscadinia cultivars. A larger introduction of Muscadinia varieties to the European continent would greatly facilitate experiments of interspecific crosses as well as stimulate biotechnological efforts to overcome the main barrier to F1 fertility caused by the differences in chromosome number. For the successful introduction of Muscadinia into the new European environment, it is necessary to overcome the difficulties associated with the physiological characteristics of the species, such as insufficient cold tolerance and very late fruit ripening. To facilitate the further discovery of valuable loci in Muscadinia and their transfer to grapevine breeding programs, we constructed a high-density linkage map using an S1 mapping population obtained from the self-pollination of M. rotundifolia cv. Dixie maintained on the southern coast of Crimea. Using ddRADseq, 3730 SNPs were ordered across 20 linkage groups spanning 2753.6 cM of the total map length. No segregation in resistance to diseases and pests was observed among the ‘Dixie’ S1 population, suggesting the presence of homozygous non-segregating resistant loci in the genetic background of ‘Dixie’. Markers with high segregation distortion showed a bias towards chromosomal intervals on linkage groups 10 and 20, where loci affecting the survival of ‘Dixie’ S1 progeny may be localized. QTLs with significant additive and dominance effects were discovered on LG14 and LG18, affecting the morphological traits associated with the vigor of growth and adaptability of young Muscadinia vines in the conditions of Crimea.

Background. Ampelographical collection of the VIR experiment station in Dagestan comprises 320 accessions of grape cultivars and 25 ecotypes of wild grape species, that are highly polymorphic in their morphological traits. As for any other large germplasm collections, the problem of genetic identification of the accessions and their originality is critical for the ampelographical collection. Genome of Vitis vinifera L. contains many polymorphic microsatellite loci, their allele diversity could be used to reveal the genetic structure of the ex situ collection as well as for the identification of duplicates. The task of the study was to estimate the level of polymorphism of four microsatellite loci that were previously recommended for the genotyping purposes in grape. The grape collection of Dagestan experiment station of VIR was investigated.Materials and methods. The analysis of microsatellite loci was based on PCR with the primers that were published previously. The size of alleles was estimated with Nanophor 05 sequencer (Syntol, Moscow). The results of the collection screening with the microsatellite markers were analyzed with Structure 2.3.4 software. The main characteristics of microsatellite loci (Polymorphic Information Content, heterozygosity) were determined using GenAlEx 6.2 program.Results and conclusion. The high level of polymorphism of the microsatellite loci VVS2, VVMD27, VVMD31, VVMD28 were detected when studying 221 accessions of the grape collection at the Dagestan experiment station. Heterozygosity of the loci was 0,50-0,83, the number of alleles per locus varied between 17 and 19, in total 70 alleles was detected. No relationship was detected between the allele combinations of accessions and their eco-geographical origin or any particular cultivar group. To reveal the genetic structure of the grape germplasm collection the larger number of SSR loci should be involved.

Two new isostructural minerals udinaite and arsenudinaite with the end-member formulae NaMg4(VO4)3 and NaMg4(AsO4)3, respectively, are found in the Arsenatnaya fumarole, Tolbachik volcano, Kamchatka, Russia. They are associated with one another and anhydrite, diopside, hematite, schäferite, berzeliite, svabite, calciojohillerite, tilasite, reznitskyite, ludwigite, rhabdoborite-group borates, forsterite, magnesioferrite, fluorapatite, pliniusite, and powellite. Both minerals occur as equant tetragonal prismatic–dipyramidal crystals up to 0.15 mm, aggregates up to 1 cm and interrupted crusts up to 2 × 2 cm2. Udinaite and arsenudinaite, visually indistinguishable from one another, are transparent, beige or brownish-yellowish, with vitreous lustre. Both minerals are optically uniaxial (–); ω = 1.785/1.777 and ε = 1.830/1.820, Dcalc. = 3.613/3.816 g·cm−3 (udinaite/arsenudinaite). The empirical formulae are: udinaite: (Na0.55Ca0.16)Σ0.71(Mg4.04Mn0.02Fe0.01)Σ4.07(V1.63As1.05P0.28Si0.03S0.01)Σ3.00O12; arsenudinaite: (Na0.57Ca0.13)Σ0.70(Mg4.01Mn0.01Fe0.01)Σ4.03(As2.07V0.84P0.10Si0.01S0.01)Σ3.03O12. Both minerals are tetragonal, I-42d, Z = 4, a = 6.8011(2)/6.8022(1), c = 19.1839(12)/19.1843(6) Å, and V = 887.35(7)/887.66(4) Å3, R1 = 0.0287/0.0119 (udinaite/arsenudinaite). Their crystal structure consists of the helical chains of edge-sharing MgO6 octahedra and isolated TO4 tetrahedra, forming a heteropolyhedral pseudo-framework with Na cations located in cavities. Both minerals are isostructural to jeffbenite. Udinaite and arsenudinaite form an isomorphous series in which the contents of T constituents vary within (in apfu): V1.6–0.1As2.8–1.0P0.4–0.0.

Abstract. Objectives The problem of physically modelling stresses in a compound solid body of revolution having a complex shape and with a complex load distribution is considered. According to the similarity criteria of stress, deformations and displacements from the volume forces decrease proportionally to the scale of similarity of geometric dimensions, which complicates their direct modelling by the photoelasticity method typically using models made from epoxy materials. Methods Based on the principle of the independent action of the forces, the initial problem is represented as the sum of two problems. In the first uniform problem, the stresses in the body of revolution from the centrifugal forces are simulated by the conventional “freezing” method. In order to solve the second nonuniform problem, the stresses in the region of the model, corresponding to the acting centrifugal forces, are “frozen”. The models are glued in a natural state at room temperature, and the compound model is annealed. Results The band patterns in sections as well as components of radial, tangential and axial stresses on contours and in sections of models are obtained by the methods of normal transmission and numerical integration of the equilibrium equation. According to the modelling criteria, the formula for the transition from stresses in models to stresses in the natural structure is established. The results of the analysis of the effect of a body's material density ratio on the stress state of the entire structure are obtained. Conclusion Axial stresses have insignificant value as compared to radial and tangential stresses; in addition, the ratio of the densities of the compound body has both a quantitative and qualitative influence on the stress state of the structure.