bluuebunny/crossref_metadata_2025 huggingface dataset:
Development of Methods for Optimization and Machine Design of the Connecting Unit of Oil-Field Equipment
Authors: Ragimova M. S.
Published: April 2024

It was determined experimentally that to provide complete sealing, the value of the contact pressure on the sealing surface must be three times greater than the internal pressure. The tightness of flange connections is provided by creating the necessary pressure on the sealing surfaces of the flanges. Moreover, the required specific pressure is created in the seals by tightening the bolts fastening the flanges. The amount of leakage is influenced by the surface roughness and the accuracy of the manufacturing of the sealing elements.
Role of the Pulse Current Duty Cycle during Titanium Tension
Authors: Stolyarov V. V.
Published: April 2024

The effect of a pulsed current on titanium tensile deformation obtained by postdeformation annealing after cold rolling of the coarse-grained and ultrafine-grained states has been considered. The effect of the duty cycle of the pulse current over a wide range on the shape of the stress–strain curves and mechanical properties has been studied. It is shown that an increase in the duty cycle results in an enhancement in the thermal effect of the current and a decrease in the flow stresses, strength, and plasticity, as well as in intense necking. A decrease in the duty cycle leads to the absence of heating and the occurrence of the electroplastic effect and an increase in the strength and plasticity, which depends on the structural state of coarse-grained titanium and the method of titanium production. The possible physical mechanisms of hardening associated with twinning, strain aging, and low-cycle fatigue have been considered.
Dynamic Control of the Efficiency of Mechanic Cutting of Material
Authors: Egorov A. V. , Shram V. G. , Kaizer Yu. F. , Zhelukevich R. B. , Lysyannikov A. V. , Bezborodov Yu. N. , Kuznetsov A. V. , Kuz’min A. V.
Published: April 2024

Solution to the problem of improvement in the efficiency of material cutting equipment is an important task in the development of modern mechanical engineering and related areas of science and technology. Various material cutting methods are available at present: mechanical, hydromechanical (hydroabrasive), electrical discharge, plasma, laser, and others. Further improvement in the efficiency of the operation of material cutting equipment is related to the development of rapid methods and tools for monitoring the efficiency of cutting processes. The existing strain gauge means for monitoring the cutting power of materials are limited by the output signal frequency of up to 100 kHz. High-speed control of the efficiency of cutting processes can be carried out on the basis of the developed dynamic method and traditional controls of high-performance material processing equipment with an output signal frequency of up to 1 MHz.
Structure, Kinematics, and Prototyping of a Parallel Manipulator with a Remote Center of Rotation
Authors: Glazunov V. A. , Laryushkin P. A. , Shalyukhin K. A.
Published: April 2024

A mechanism with a remote center of rotation, intended for use in medicine, and in particular, minimally invasive operations, is discussed. The basic mechanism consists of two parallelograms with common links, which allows the surgical instrument to duplicate the movement of the drive link of the mechanism. To ensure greater rigidity of the mechanism, it is proposed to introduce drive redundancy through the use of an additional RRR dyad with a drive pair. The position problem has been solved for the resulting mechanism. A 3D model and a prototype of the mechanism have been also presented.
The Two-Parameter Fracture Criterion Taking into Account Two-Dimensional Deformation Constraints at the Front of a Mixed-Type Crack
Authors: Pokrovskii A. M. , Matvienko Yu. G.
Published: April 2024

In this article, a new fracture criterion for a mixed-type crack (type I + type II) is proposed. It is based on the assumption that the maximum tangential stresses in the prefracture region are equal to the local strength of the material. In this case, the size of the prefracture area and the local strength are determined taking into account nonsingular Тхx and Тzz stresses included in the expansion of the Williams stress function. The use of Тхx and Тzz stresses in the calculations allows one to describe the two-dimensional local constraint of the deformation along the crack front in three-dimensional bodies. In addition to KI and KII, the expression for the effective stress intensity factor (SIF) includes the ratios of the Тхx and Тzz stresses to the yield strength. This makes it possible to take into account the constraint of deformations in the transverse and longitudinal directions of the crack front, respectively. An example of the implementation of the developed criterion in relation to the determination of the fracture load of a tensile-stressed plate with a through inclined crack is given. Dependences of the Тxx and Тzz stresses on the plate thickness are presented for various crack slopes and plate thicknesses. It is shown that an increase in the plate thickness and a decrease in the crack slope lead to a decrease in the fracture load.
Can Observations of 511 keV Line From the M31 Galaxy Shed Light on the AGN Jet Composition? 1 [1]
Authors: Nizamov B. A. , Pshirkov M. S.
Published: April 2024

Positron annihilation line at 511 keV is a known component of the gamma-ray diffuse emission. It is believed to be produced in the Galaxy, but there could be possible extragalactic contribution as well. E.g., positrons can be produced in jets of active galactic nuclei (AGN) and after that accumulate and gradually annihilate in hot gaseous halos around galaxies. In this work we test this hypothesis in application to an individual object – the Andromeda galaxy (M31) which is close and has a supermassive black hole in its center, which powered an AGN before. We compute the growth history of the supermassive black hole in M31, relate it to the evolution of jet luminosity and estimate the positron content in its halo. We calculate the 511 keV photon flux due to positron annihilation which should be observed at Earth and find the value of around \(10^{-4}\) photon cm\({}^{-2}\)s\({}^{-1}\). It is very close to the observational limits (\(10^{-4}\)photon cm\({}^{-2}\)s\({}^{-1}\)) set by the INTEGRAL/SPI in the assumption of the point source, so further observations would be able to constrain leptonic models of the jets and propagation of cosmic rays in the circumgalactic medium of large spiral galaxies.
Explanation of the Anomalous Outburst Activity of Comet 29P/Schwassmann–Wachmann 1: The Hypothesis about the Existence of Large Satellites
Authors: Medvedev Yu. D. , Pavlov S. R.
Published: April 2024

We explain the anomalous outburst activity of comet 29P/Schwassmann–Wachmann 1 by the existence of satellites touching the surface of the comet nucleus at the pericenters of their orbits. It is assumed that the satellites move in eccentric orbits and a large amount of dust, the reflection of light from which causes periodic outbursts in brightness (BAA 2023), is ejected as a result of their collisions with the dust layer of the nucleus. Depending on the depth of penetration of the satellites into the dust layer, outbursts in comet brightness of various intensities occur. An improvement of the comet orbit by invoking positional observations allows the preferred direction of the ejection of material to be determined from the photocenter offset, which we interpret as the direction of the velocity vector of the largest satellite at the pericenter. The results of our numerical simulations of the ejection and subsequent motion of dust particles caused by the contact of the satellite with the dust layer of the comet nucleus explain the formation of the structures observed in the comet: the dust jets and their mirror symmetry as well as the extent of the region of material ejection from the surface of the comet nucleus.
Activity of the Young Solar Analog HD 109833 and Estimates of the Mass Loss Rate from the Atmospheres of Its Two Planets
Authors: Savanov I. S.
Published: April 2024

We present the results of our analysis of the manifestations of activity in the young solar analog HD 109833 and estimate the mass loss rate from the atmospheres of its two planets. HD 109833 probably belongs to the Lower Centaurus Crux (LCC) association with an age of 27 ± 3 Myr, but it is not inconceivable that the star is only spatially associated with the association and may be older, although in any case its age does not exceed 100–200 Myr. Based on data from the TESS archive for HD 109833, we have determined the stellar rotation period P = 5.08 ± 0.30 days and the photometric variability amplitude (about 0.6% of the mean stellar brightness) and estimated the spot areas on its surface, which exceed the maximum sunspot area and are 15 200–17 700 m.s.h. Based on data from the All-Sky Automated Survey archive, we have revealed a stellar activity cycle with a duration 1950 days (5.3 years). Both planets in the HD 109833 system are characterized as sub-Neptunes with radii of 2.9 and 2.6 R⊕ and periods of 9.2 and 13.9 days. The mass loss rates by the planetary atmospheres have been found using an approximate formula corresponding to the energy-limited atmospheric escape model. To estimate the XUV flux, we have applied analytical dependences relating the flux and the parameter logR'HK and information about the distribution of these quantities for G-type stars, suggesting that there are two pronounced peaks with maxima for values -0,5 and -4,5 dex in low-activity and active stars, respectively. In addition, we have used the relation between the X-ray flux from the star and logFXUV . The value found is comparable to the estimate obtained by applying the parameter logR'HK for active stars and exceeds it by a factor of 4. Both exoplanets HD 109833 b and c being considered by us fall into the region on the (M-R) diagram in which the populations of rocky and volatile-rich exoplanets overlap and do not allow their masses to be estimated unambiguously. Our calculations were performed for two cases—rocky exoplanets and volatile-rich exoplanets. The masses of the exoplanets HD 109833 b and c are, respectively, 34.9 and 24 M⊕ for rocky exoplanets and 9.3 and 7.8 M⊕ for volatile-rich exoplanets. We present the results of our calculations of the atmospheric mass loss rates by the planets HD 109833 b and c while varying the parameters related to the estimates of the planetary masses and the UV flux incident on the planets. The parameter M for HD 109833 b and c varies in the ranges from 9.60 ×107 to 1.38 ×1010 g s-1 and from 4.56 ×107 to 5.28 ×109 g s-1, respectively. The high mass loss rates found can be a consequence of a fairly high XUV flux from the solar-type star (an analog of the young active Sun) and a fairly close location of the planets from the host star.
Theoretical Period–Radius and Period–Luminosity Relations
for Mira Variables with Solar Metallicity
Authors: Fadeev Yu. А.
Published: April 2024

Evolutionary sequences of AGB stars with initial masses on the main sequence MZAMS =1.5 M , 2 M and 3 M were computed for the initial metallicity Z = 0.014. Selected models ofevolutionary sequences with envelopes under thermal equilibrium were used as initial conditions forcalculation of nonlinear stellar pulsations. The hydrodynamic models of each evolutionary sequence areshown to concentrate along the continuous line in the period–radius and period–luminosity diagrams.The theoretical period–radius and period–luminosity relations differ from one another for different main–sequence star masses because the stellar luminosity of AGB stars depends on the degenerate carboncore mass which increases with increasing MZAMS. In hydrodynamic models of evolutionary sequencesMZAMS = 2 M and MZAMS = 3 M the periods of the first overtone pulsators are 86 d ≤ Π ≤ 123 dand 174 d ≤ Π ≤ 204 d, whereas all models of the evolutionary sequence MZAMS = 1.5 M oscillate inthe fundamental mode. Fairly regular radial oscillations exist in stars with pulsation periods Π 500 d.In models with longer periods the amplitude rapidly increases with increasing Π and oscillations becomeirregular.
Expansion of the Soft X-ray Source and “Magnetic Detonation”
in Solar Flares
Authors: Struminsky A. B. , Sadovski A. M. , Grigorieva I. Yu.
Published: April 2024

The detection of radio emission from solar flares at frequencies below ∼2 GHz allows the upperlimits for the characteristic size of the soft X-ray (SXR) source L(t) to be estimated under the assumptionthat the density n(t) is determined by the plasma frequency νp. If the SXR source with a higher density isinside the radio source, then the size of the SXR source will be L(t) (EM(t)/2n(t)2)1/3, where EM(t)is the emission measure. For three flares (C7.2 on December 22, 2009, M2.9 on July 6, 2012, and X1.1 onJuly 6, 2012) we calculate the expansion speeds of the SXR source V (t) ∼ dL(t)/dt, which are comparedwith the estimates of the sound speed and the Alfve´ n speed. By “magnetic detonation” wemean the processof the propagation of magnetic reconnectionwith a supersonic speed in eruptive flares. Magnetic detonationand the succeeding coronal mass ejection (CME) were realized in the December 22, 2009 C7.2 and July 6,2012 X1.1 flares, in which supersonic and super-Alfve´ n speeds were reached if the density of the SXRsource was lower than 2.1 × 109 and 7.4 × 108 cm−3 (νp 410 and 245 MHz), respectively. There wereno magnetic detonation and CME in the July 6, 2012 M2.9 flare, whose radio emission frequencies wereonly above 1415 MHz (n 2.5 × 1010 cm−3). For magnetic detonation in the July 6, 2012 X1.1 flare wehave estimated the magnetic field strength, the reconnection electric field strength, the plasma flow, and theCME mass.
Structural Organization of GABA- and Nitroxidergic Systems of Subfornical Organ in Wistar Rats Postnatal Development
Authors: Razenkova V. A. , Korzhevskii D. E.
Published: April 2024

The subfornical organ (SFO) is one of the circumventricular organs (CVOs) of the mammalian nervous system responsible for maintaining the energy and water and sodium balance. Despite notable interest in the SFO and its physiological functions, the organization of individual populations of SFO cells, as well as their interactions remain to be clearly established. In this study we examined GABA and nitroxidergic systems of SFO using immunohistochemical (IHC) methods. The brain of male Wistar rats at different stages of postnatal development: postnatal day 7 (P7), 14 (P14) and adult (4–6 months), was examined. The data obtained allowed us to characterize changes in the activity of the GABA- and nitroxidergic systems of the SFO during development. In adult rats, three subpopulations of nitroxidergic cells, differing in the intensity of the reaction and tissue localization, can be distinguished. The revealed morphological heterogeneity of nitroxidergic cells in SFO may reflect their diverse functional status.
Endoplasmic Reticulum Stress Inducer Dithiothreitol Affects the Morphology and Motility of Cultured Human Dermal Fibroblasts and Fibrosarcome HT1080 Cell Line
Authors: Turishcheva E. P. , Ashniev G. A. , Vildanova M. S. , Smirnova E. A.
Published: April 2024

Some inducers of endoplasmic reticulum (ER) stress can affect the motility of normal and tumor cells. However, it is unknown what mechanisms mediate this effect and whether it is a consequence of ER stress. The aim of our work was to study the effect of the ER stress inducer dithiothreitol (DTT) on morphological features reflecting the locomotor properties of cells, as well as directly on the migratory properties of cultured human dermal fibroblasts and fibrosarcoma HT1080 cells. We have shown that DTT causes disruption of the organization of actin cytoskeleton in both types of cells, which is accompanied by a change in the cell surface and shape of cells, as well as a decrease in their spreading area. In addition, a decrease in the number of focal contacts was observed in dermal fibroblasts. DTT also reduced the motility of dermal fibroblasts and fibrosarcoma cells. To analyze cell motility and determine the moment of its change, we developed a method which showed that the change in the migratory properties of fibrosarcoma cells cultured with DTT began earlier than in dermal fibroblasts. Thus, activation of ER stress by DTT is accompanied by a change in the organization of the actin cytoskeleton and motility in normal and tumor human cells. Consequently, ER stress triggered by various inducers with different mechanisms of action affects the motility of normal and tumor cells, which must be taken into account when developing antitumor drugs that cause cell death through activation of ER stress.
Effect Of Exogenous IAA and BAP on the Metabolism in the Adhesion Zone Cells of the Pea Seegling Roots (Pisum sativum L.) in the Initial Periods of Interaction with Rhizobium leguminosarum bv. viceae
Authors: Makarova L. E. , Akimova G. P. , Ischenko A. A. , Bizikov P. A. , Kopyrtina T. V.
Published: April 2024

In the adhesion zone of the etiolated pea seedling roots, located at a distance of 5–15 mm from its apex, 1 and 24 hours after inoculation with the bacteria Rhizobium, the effect of exogenous 10–11 M indol-acetic acid (IAA) and 10–9 M 6-benzylaminopurine (BAP) on cell metabolism was investigated. The inoculated seedlings were used as control that is not exposed to the action of phytohormones. Phytohormone-induced changes in the activity of soluble and cell wall-related peroxidases (PO) and polyphenol oxidases (PPO), tissue concentrations of hydrogen peroxide (H2O2), nitric oxide (NO), “soluble” (extracted by ethyl acetate and n-butanol) and “insoluble” phenolic compounds (PCs), flavonoids are discussed. The analysis of the obtained results shows that in both observation periods, the exogenous effect of the IAA enhanced protective responses in the cells of the adhesion zone, and the action of BAP weakened them. It is shown that the differences in the metabolism of adhesion zone cells resulting from the action of exogenous BAP and IAA are related to their diametrically opposite effect on nodulation.
New Inhibitors of Pancreatic α-amylase from Rhaponticum uniflorum
Authors: Olennikov D. N. , Kashchenko N. I.
Published: April 2024

The basic strategy for the treatment of diabetes mellitus is the control of postprandial glucose levels, and therefore pancreatic α-amylase that hydrolyzes complex carbohydrates is an important enzymatic target for the scientific research. In the present study, an aqueous extract and its ethyl acetate fraction (EAF) from the seeds of Rhaponticum uniflorum had a pronounced inhibitory effect on the activity of human pancreatic α-amylase. Sixteen metabolites were isolated after the chromatographic separation of EAF and characterized as 4-O-, 5-O-, 3,4-di-O-, 3,5-di-O-, 4,5-di-O-caffeoylquinic acid, 6-hydroxyluteolin 7-O-glucoside, rhaunoside B, luteolin 7-O-(6"-O-caffeoyl)-glucoside, luteolin, carthamoside, carthamogenin, tracheloside, isoferuloyl-serotonin, 20-hydroxyecdysone, 2-deoxy-20-hydroxyecdysone and a new natural compound, which was carthamogenin 4-O-(6''-O-acetyl)-β-D-glucopyranoside (6''-O-acetyl-cartamoside). Quantitative HPLC data indicated a different distribution of the individual components between the endosperm and the seed coat. The study of the compounds effect on the activity of human pancreatic α-amylase showed that some flavonoids, caffeoylquinic acids, lignans and serotonin derivatives had a pronounced inhibitory effect. These results support the conclusion that Rhaponticum uniflorum seeds may be a useful natural source for the development of α-amylase inhibitory agents.
A New Method for Express Detection of Antibiotic Resistance
Authors: Pleskova S. N. , Lazarenko E. V. , Sudakova I. S. , Kriukov R. N. , Bezrukov N. A.
Published: April 2024

The oscillation mode of an atomic force microscope (AFM) was used to create a highly sensitive real-time detection system for antibiotic resistance. This mode allows to evaluate the sensitivity or resistance of Gram-negative (Escherichia coli) and Gram-positive (Staphylococcus aureus) bacteria to an antibiotic in 15–30 minutes. The analytical signal (changes in the amplitude-frequency characteristics of the cantilever) is based on the metabolic activity of bacteria. Bacteria was adding on the cantilever and was causing it to oscillate with high amplitude. If the bacteria are sensitive to the antibiotic, the amplitude drops statistically significant within 15–30 minutes, if the bacteria are resistant, then the amplitude either does not change or increases. The obtained results were comparable with the disk diffusion method.
Probiotic Properties of Saccharomycetes (Review)
Authors: Ryabtsevа S. A. , Khramtsov A. G. , Sazanova S. N. , Budkevich R. O. , Fedortsov N. M. , Veziryan A. A.
Published: April 2024

The purpose of the review is to summarize and analyze information on the molecular genetic basis and methods for studying the probiotic activity of Saccharomycetes fungi, the mechanisms of their physiological action, and their application in biotechnology. The relevance of research in this area is confirmed by the dynamics of the growth of publications. The effectiveness of Saccharomyces boulardii in the treatment and prevention of diarrhea of various etiologies, relapses of C. difficile infection, side effects of H. pylori infection therapy has been established with a high level of evidence. Genetic, cytological, cultural and biochemical features of S. boulardii determine their probiotic activity. Other Saccharomyces strains with probiotic potential are most often isolated from national fermented plant and dairy products. A unified methodology for studying the probiotic properties of yeast has not yet been created; clinical trials involving people are needed to confirm their status. Promising probiotics are strains of the species S. cerevisiae and K. marxianus, which have an international safety status. Possible mechanisms of physiological action of Saccharomycetes include antimicrobial and antitoxic, trophic, antisecretory and anti-inflammatory effects. Some of the mechanisms of yeast probiotic action differ from those of bacteria, and not all of them are yet understood. Saccharomycetes probiotics can be used to improve the biological value, quality and safety of food products.
Immobilization of Glucose Oxidase on Sodium Alginate Microspheres
Authors: Stadolnikova P. Yu. , Tikhonov B. B. , Prutenskaya E. A. , Sidorov A. I. , Sulman M. G.
Published: April 2024

Glucose oxidase from Aspergillus niger was immobilized by covalent cross-linking on the surface of alginate microspheres obtained by emulsification/internal gelation method. The catalytic properties of the free and immobilized enzyme were compared. The size of the resulting microspheres was less than 200 μm. Experiments have shown that the immobilized enzyme has an activity 40% lower than the free glucose oxidase, but it has a high activity in a wider range of temperatures and pH values. Kinetic parameters for native glucose oxidase: limit reaction rate – 0.341 mM · min–1, Michaelis constant – 5.41 mM; for immobilized: limit reaction rate – 0.203 mM · min–1, Michaelis constant – 11.43 mM. In infrared Fourier spectra of diffusion reflection of semi-products of biocatalyst synthesis, peaks corresponding to the formed covalent bonds between the enzyme and the carrier were revealed. Synthesized biocatalyst can be used in food industry as bakery improver, in chemical and pharmaceutical industry for production of gluconic acid and in analytical chemistry for determination of glucose concentration.
Immobilized Microorganisms-based Biopreparation as a Major Component for New Generation High-effeciency Organic Fertilizers
Authors: Yudina N. Yu. , Kozlova T. N. , Abramova T. N. , Arlyapov V. A. , Asulyan L. D. , Alferov V. A. , Reshetilov A. N.
Published: April 2024

Two biopreparations made of the bacteria Bacillus megaterium and Azotobacter chroococcum immobilized in modified polyvinyl alcohol hydrogel have been created. It has been shown that after application of the constructed biopreparations, an increase in soil moisture content (by a factor of two), germination (by up 100%), the length of the cress stem and roots (15–30%) was achieved. The addition of Azotobacter chroococcum-based biopreparation led to a 2-time increase of nitrogen in soil. The survival period for bacteria immobilized in hydrogel based on polyvinyl alcohol modified with succinic acid was longer than 30 days. It is concluded that the studied biopreparationsexhibited high potential as a major material for efficient biofertilizer of new generation.
Preparation of Phage Antibodies to Heat Shock Proteins and Studying the Dynamics of their Accumulation in Mice with Xenotransplant Tumors
Authors: Dykman L. A. , Staroverov S. A. , Vyrshchikov R. D. , Fursova K. K. , Brovko F. A. , Soldatov D. A. , Guliy O. I.
Published: April 2024

Using a naïve human scFv phage library, affinity selection of miniantibodies specific to heat shock proteins isolated from MH22a hepatoma cells and Sp2/0-Ag14 plasmacytoma cells was carried out. Using the obtained phage antibodies by dot-immunoassay and enzyme-linked immunosorbent assay, the dynamics of the concentration of heat shock proteins in the blood serum of mice with implanted tumor cells of the MH22a line was studied. Starting from the 14th day after xenotransplantation, there was a gradual increase in the level of heat shock proteins in the blood serum. It was found that after implantation of tumor cells, tumor growth was accompanied by a significant increase in the accumulation of heat shock proteins in the blood serum. It has been shown that miniantibodies specific to heat shock proteins are an effective tool for determining and monitoring the accumulation of heat shock proteins in the blood serum of animals.
Caffeic Acid in Various Formulations as a Growth and Resistance Regulator of Potato Microclones in in vitro Culture
Authors: Yalouskaya N. A. , Kalatskaja J. N. , Laman N. A. , Nikalaichuk V. V. , Kraskouski A. N. , Hileuskaya K. S.
Published: April 2024

The article discusses the influence of caffeic acid (CA), its mix with chitosan (CHT + CA) and chitosan-based conjugate (CHT-CA) on growth and proline content of microclone potato plants (Solanum tuberosum L.) in in vitro culture under optimal conditions and under prolonged osmotic stress caused by polyethylene glycol. Under optimal conditions CHT-CA and CA, acting as moderate strength stressors, accelerate the growth and development of potato microclones and increase the proline accumulation in the stems. Under osmotic stress CA and CHT-CA promote the resistance of potato microclones and maintain their active growth. And such effect persists during the reparation period. The mechanical mix CHT + CA causes inhibition of microclonal plants’ growth and development accompanied by a significant accumulation of proline which is aggravated under stress.
Cyclodextrin Glucanotransferase of Alkalophilic Strain Caldalkalibacillus mannanilyticus IB-OR17-B1
Authors: Milman P. Yu. , Gilvanova E. A. , Aktuganov G. E.
Published: April 2024

Extracellular cyclodextrin glucanotransferase (CGTase, K.F.2.1.19) was characterized for the first time in a strain of bacteria of the species Caldalkalibacillus mannanilyticus IB-OR17-B1. The enzyme was isolated from the culture supernatant using ultrafiltration and affinity adsorption on corn starch. The specific activity of the CGTase was increased in 18-fold as a result of purification with the enzyme yield 56%. The molecular mass of the purified enzyme was 70 kDa according to the denaturing electrophoresis in polyacrylamide gel. The CGTase of C. mannanilyticus IB-OR17-B1 demonstrated a maximal cyclizing activity under pH 8 and temperature 60°C, respectively, and it was stable in the pH range 7–10 and temperatures ≤70°C. The thermal stability of the enzyme under 70°C increased by 10–15% in the presence 5–10 mM of calcium and magnesium salts. The cations of Ag+, Cu2+, Zn2+, Fe2+ and Fe3+ in concentration 5 mM inhibited a CGTase activity by 90, 26, 23, 18 and 11%, respectively. The purified CGTase under optimal conditions and enzyme-substrate ratio 1 U/g converted a potato starch during 24 h to mixture of α-, β- and γ-cyclodextrins with mass ratio 38.8 : 52.6 : 8.6 and yield 42%.
Conjugation Vector Delivery System for Molecular Cloning into Cells of Bacteria of The Genus Bacillus
Authors: Gurinovich A. S. , Fedyushko I. A. , Titok М. А.
Published: April 2024

A delivery system for vectors for molecular cloning into bacterial cells of the genus Bacillus has been developed. A specific feature of the developed system is the use of the pBS72 plasmid, which provides the conjugative transfer of the conditionally lethal vector pKS1mob obtained into the cells of the studied bacteria. The ability of vector pKS1mob to replicate in Escherichia coli and B. subtilis cells at a low temperature (30°C), the presence of two polylinkers around the kanamycin resistance gene makes it possible to clone target gene fragments into its composition using traditional genetic engineering approaches. Inactivation of the rok gene in the pBS72 plasmid made it possible to transform the strain containing it with the constructed vector pKS1mob with high efficiency. Crossing the donor strain B. subtilis 168, containing conjugative pBS72 and pKS1mob mobilizable plasmids, with a recipient strain of the genus Bacillus made it possible to introduce the pKS1mob plasmid into it. The possibility of using the created system for inactivation of gene codY of bacteria Bacillus licheniformis was shown.
Codes for exact support recovery of sparse vectors from inaccurate linear measurements and their decoding
Authors: Fernandez Marcel , Kabatiansky G. A , Kruglik S. A , Miao Ying
Published: April 2024

We construct codes that allow to exactly recover the support of an unknown sparse vector with almost equal absolute values of all nonzero coordinates given results of linear measurements in the presence of noise with ℓp-norm bounded from above. We propose a decoding algorithm with asymptotically minimum complexity.
Overparameterized maximum likelihood tests for detection of sparse vectors
Authors: Golubev G. K
Published: April 2024

We address the problem of detecting a sparse high-dimensional vector against white Gaussian noise. An unknown vector is assumed to have only p nonzero components, whose positions and sizes are unknown, the number p being on one hand large but on the other hand small as compared to the dimension. The maximum likelihood (ML) test in this problem has a simple form and, certainly, depends of p. We study statistical properties of overparametrized ML tests, i.e., those constructed based on the assumption that the number of nonzero components of the vector is q (q > p) in a situation where the vector actually has only p nonzero components. We show that in some cases overparametrized tests can be better than standard ML tests.
Testing the satisfiability of algebraic formulas over the field of two elements
Authors: Vyalyi M. N
Published: April 2024

We construct a probabilistic polynomial algorithm for testing the satisfiability of algebraic formulas of depth 3 over the two-element field, with addition as the top operation in the formulas. An algorithm with the same characteristics exists for the problem of testing whether a polynomial given by formulas of this type is identically zero (PIT problem). However, these problems and algorithms for their solution are essentially different. The probabilistic algorithm for the PIT problem is based on the Schwartz-Zippel lemma, whereas the satisfiability testing algorithm proposed in this paper is based on the Valiant-Vazirani lemma.
Geometric interpretation of the entropy of so c systems
Authors: Dvorkin G. D
Published: April 2024

We consider a geometric approach to the notion of metric entropy. We justify the possibility of this approach for the class of Borel invariant ergodic probability measures on so c systems, which is the rst result of such generality for non-Markovian systems.
Existence of sequences satisfying bilinear type recurrence relations
Authors: Illarionov A. A
Published: April 2024

We study sequences $\left\{A_n\right\}_{n=-\infty}^{+\infty}$ of elements of an arbitrary field $\mathbb{F}$ that satisfy decompositions of the form $A_{m+n} A_{m-n}=a_1(m) b_1(n)+a_2(m) b_2(n)$, $A_{m+n+1} A_{m-n}=\tilde a_1(m) \tilde b_1(n)+\tilde a_2(m) \tilde b_2(n)$, where $a_1,a_2,b_1,b_2\colon \mathbb{Z}\to\mathbb{F}$. We prove some results concerning the existence and uniqueness of such sequences. The results are used to construct analogs of the Diffie-Hellman and ElGamal cryptographic algorithms. The discrete logarithm problem is considered in the group $(S,+)$, where the set $S$ consists of quadruples $S(n)=(A_{n-1},A_n, A_{n+1}, A_{n+2})$, $n\in\mathbb{Z}$, and $S(n)+S(m)=S(n+m)$.
Swinging pendulum: a model or metaphor for change in policy on nationalities in multi-composite states? the case of USSR and post-soviet Russia
Authors: Pain Emil A.
Published: April 2024

Nationalities’ policy in multi-composite states is often characterized by its fluctuance and even inconsistency. It is essential to study the said characteristics to understand the general patterns of ethnopolitics. The underlying reasons for significant fluctuations in Soviet and Russian nationalities’ policy are analyzed. The concepts of “ethnopolitical pendulum” and “pendulum of nationalities’ policy” are critically assessed. Most attention is paid to the issue of the Soviet leadership’s real and perceived inconsistency in following such key principles of nationalities’ policy in the USSR as the right of nations to self-determination, federalism, and the rights of ethnic minorities. Based on this analysis, the following conclusions are made. First, the changes in Soviet nationalities’ policy were caused by shifting current political concerns, which often demanded correcting or overruling ideological principles. Second, the pattern of a pendulum is more of a metaphor than an explanatory model for analyzing fluctuations in this field. Finally, the Soviet experience remains understudied in modern Russian nationalities’ policy, which has a high probability of ethnic and confessional mobilization.
The influence of political power on models of industrial organization: institutional approach
Authors: Fedorov Sergei I.
Published: April 2024

The choice of industrial organization mechanisms always takes place in the context of approaches to economic regulation set by the political elite. In times of large-scale political upheavals which are taking place in 2022, economists are more and more concerned with this context, but operational tools that would allow it to take into account when analyzing the mechanisms of governance have not yet been found. This article is developing such tools from the perspective of the New Institutional Economics: combination of the “social orders” concept developed by D. North, J. Wallis, B. Weingast and the “mechanisms of governance” by O. Williamson. It is concluded that taking into account only the transaction costs minimizing principle while choosing the mechanism of governance excludes an important factor: the opportunism of politicians, which are often directly involved in the establishment of governance mechanisms.
Eurasian integration in the new geopolitical realities
Authors: Shuping Yang
Published: April 2024

The term “Eurasia” has had different geopolitical meanings in world history. The concept of Eurasia and Eurasian integration should be adapted to the new geopolitical realities. Based on the Russian, Western, Chinese and other literature, the historical transition from Minor to Greater Eurasia is analyzed. It is argued that the concept of Greater Eurasia corresponds to the processes taking place in today’s world. In general, Greater Eurasia is a broad and open concept that includes the entire Eurasian continental space: China, the European Union, India, Pakistan, South Korea, Iran, ASEAN and post-Soviet territories. The changes in the concept of “Eurasia” calls for investigation of the essence of Eurasian integration. In this study it is divided into three levels: Eurasian Minor integration, general Eurasian integration, and a large Eurasian community of common destiny. The three models can replace the ambiguous interpretation of the original concept of Eurasian integration.
Political mentality and mental traps of political communication
Authors: Pushkareva Galina V.
Published: April 2024

Political mentality is considered a kind of mental activity that provides an understanding of political reality, determines the content of observed political events and the meaning of the actions of their participants. It is shown how mental activity of a person is organized, helping to navigate in the political space. Attention is drawn to the fact that perception is subject to the “rut law” concept based on mental traps that capture the mind, which form judgments about a political phenomenon and subordinate it to its own logic. The nature of mental traps is revealed and their types are characterized. The heterogeneity of the political and cultural environment contributes to the emergence of political mentalities that differ in their content, as well as in interpreting political processes and phenomena. Political polymentality can become a serious problem for society. It leads to the emergence of groups that have different perceptions of the unfolding political processes, interpretations of the content of ongoing events, and evaluation of the actions of the authorities.
Representation of women in regional parliaments: testing the model of traditional gender roles
Authors: Mukhametov Ruslan S.
Published: April 2024

The reasons for the limited women’s representation in the parliaments of the constituent entities of the Russian Federation are studied. Statistics show that in some Russian regions the proportion of women deputies in regional assemblies is higher than in the others. The classical point of view states that women’s participation in politics as people’s representatives is determined by gender norms and roles. Assessments of the influence of traditional gender roles were carried out based on Russian statistics. Information on the subjects of the Russian Federation was used in analysis. The regression analysis (step-by-step regression method) was used as a research method. The theoretical and methodological basis of the work is the theory of gender roles by A. Eagly. The conducted research refutes the formulated hypothesis. Traditional gender views have at most indirect influence on the parliamentary representation of women, mediated by the procedure of selection of candidates by political parties and civil society organizations. Provisions of the “resource” model of women’s political activism also weren’t confirmed. It is shown that the share of women deputies in the legislatures of the constituent entities of the Russian Federation which use the system of party lists during the election is less than in regional legislative bodies formed according to the majority or mixed electoral system.
The left-wing ideology of the new elites: from luxury beliefs to universal humanism
Authors: Davydov Dmitriy A.
Published: April 2024

It is substantiated that most of the modern Western left-wing political discourses constitute the ideology of new, “post-bourgeois” elites. This ideology is a mixture of concepts conditioned by the post-materialist values of the “cognitive” elites and the “creative class”. It is noted that a significant part of left-wing progressive ideas (including intersectional Marxism) leads to policies that counter the interests of a significant portion of the poor and socially vulnerable people. It is shown that the hypocrisy of the new elites, for whom leftist ideas have become a way of demonstrating their status (“luxury beliefs”), is not the only reason for this contradiction. The key problem is the unevenness of the movement towards post-capitalism. While classical Marxism assumed the primary importance of meeting the basic needs of everyone without exception, today only a relative minority achieved the state of “existential security”. This elite minority is imbued with communist values, but their anti-bourgeois universal humanism with its’ wide range of goals (from the idea of “open borders” to the protection of the rights and opportunities of “non-human animals”) is often not relevant in the context of the world in which many people still face material need and scarcity.
Rebooting social reality in the space of quantified symbolic objects: “ontologization of the figure”
Authors: Ignatyev Vladimir I.
Published: April 2024

The article examines one side of the process of ontologization - the transformation of the symbolic world into a world of empirically detectable things and phenomena. The rationale for the thesis is that in the process of digitalization a fragment of being is replaced by its symbol, and the ontologization of “figure” appears as the emanation of the symbol in a fundamentally new fragment of existence, in the embodied semblance of a sign. This process is to be interpreted as “ontologization of the figure” - the transfer of the properties of a symbolic object (constructed as a digital quantified object and including only quantitative characteristics) into a new fragment of reality, which acquires the quality of being exclusively calculated. The conclusion is that the “figure” as an abstraction and phenomenon of consciousness can move from the ideal to the material state and begin its own existence through inclusion into human activity as a symbolic tool of practice, having a dominant effect on the material-subject world and on human behavior. The ontologization of “figure” culminates in the recoding of the properties of real objects and properties of human bodies with physical and psycho-physiological properties into their alternative abstract digital counterparts.
Sovereignty as a way out of collective anxiety: the EU’s discourse on money, health, and food
Authors: Romanova Tatiana A. , Kotsur Gleb V.
Published: April 2024

The European Union (EU) has developed as an actor that overcomes national sovereignty in global politics. Yet, as of 2017, the EU has used the “sovereignty” category at the supranational level, both in general and in combination with “sectoral” adjectives. The objective of research is to demonstrate that the use of “sectoral sovereignty” can be examined as the EU’s work with collective anxiety, which results from various challenges that can hardly be controlled. The anxiety is examined in the context of emotion culture with the focus on public images of sentiments whereas the incorporation of sovereignty in the EU’s discourse comes out as a “self-identification with an aggressor” - with something that has previously been viewed as a threat to integration. In the EU’s discourse “sovereignty” means a set of actions targeted at drawing a border between the internal and the external, at establishing higher autonomy. Three cases are examined with the help of discourse analysis: challenge of technological companies and monetary sovereignty; pandemic threat and health sovereignty; problems in global agricultural trade and food sovereignty. In each case elements of the EU’s collective anxiety are described; sovereignty as a system of actions to address anxiety is identified; the overall support for this work in the EU is revealed. The conclusions are drawn on when and where “sectoral” sovereignty helps the EU to limit its anxiety. Yet, the successful incorporation of sovereignty in the EU’s discourse does not mean a complete overcoming of anxiety; instead, dialectic relations between collective anxiety and sovereignty emerge.
Spatial dimension of subjective well-being
Authors: Goffe Nina V.
Published: April 2024

The rural-urban paradox of happiness is examined that, in developed countries, manifests itself in higher life satisfaction of rural residents compared to urban residents. This topic has become increasingly important due to the dynamics of urbanization and the overwhelming majority of the global population settling in urban areas. Based on the analysis of statistical data and foreign literature, the aim of the study is to highlight the issues associated with defining the paradox and analyze various approaches to this topic. As the cost of living in urban areas rises, the paradox might become more pronounced, and the territorial differentiation of subjective well-being is likely to increase. In this scenario, human civilization will face fundamental challenges relating to the future of cities and the spatial distribution of the global population.
Individual values and perceived discrimination as predictors for the formation of russian identity
Authors: Fedotova Vera A. , Cherkasova Elena V.
Published: April 2024

The concept of identity is increasingly becoming an object of study in many social sciences. Identity plays one of the main roles in the context of growing globalization processes. The ethnic and civic identity of Russians, having become important elements of social identity, are markers of socio-economic and political changes. Scientists came to the conclusion that the formation of civil and ethnic identity occurs in the process of socialization under the influence of various factors of the sociocultural context - cultural, historical, political and economic. In the presented study, the emphasis is on checking the influence of two factors on the formation of the identity of Russians - cultural and historical. Individual values act as indicators of the cultural factor, and perceived ethnic and civil discrimination serve as indicators of the historical factor. The study was conducted with the participation of 1014 respondents. The average age of the studied sample was 41 years. The study revealed the ethnic and civic identity of Russians, their dominant values, as well as perceived ethnic and civic discrimination. It has been established that the cultural factor has the most significant impact on ethnic and civic identity, while the historical factor has a much smaller impact on these variables. At the same time, perceived civic discrimination has the least impact on the formation of ethnic and civic identity. It was also found that the key positive regressor in relation to the civil and ethnic identity of Russians is the value of “tradition”.
Staurolite in Metabasites: P-T-X Conditions and the Ratios of Petrogenic Components as a Criterion of the Appearance of Staurolite
Authors: Borisova E. B. , Baltybaev Sh. K. , Connolly J. A. D.
Published: April 2024

In addition to the widespread Fe-Mg staurolite, typical for medium-temperature high-alumina metapelites, there are a number of finds of magnesian staurolite in metamorphosed mafic rocks – metabasites. Based on thermodynamic modeling and analysis of the mineral formation patterns, the most significant factors of the staurolite formation in metabasites have been revealed. For the formation of staurolite in metabasites, in contrast to staurolite in low- and medium-pressure metapelites, medium- and high-pressure conditions of metamorphism are necessary. An increase in the proportion of carbon dioxide in the composition of the water-carbon dioxide fluid has practically no effect on staurolite-forming mineral reactions, but leads to their shift to lower temperatures and higher pressures. Al, Fe, Mg, Ca are critical petrogenic rock components for the formation of magnesian staurolite, the contents and ratios of which primarily determine the stability of staurolite in metabasites. To understand the regularities of mineral formation, it seems appropriate to divide metabasites into subgroups of predominantly magnesian, iron-magnesian, and ferruginous protoliths. Based on this division, three petrochemical modules are proposed in the form of the ratio of rock-forming components: MgO/CaO, CaO/FM, Al2O3/FM, based on which it is possible to predict the appearance of staurolite in the basic rock when the corresponding P-T conditions of metamorphism are reached.