bluuebunny/crossref_metadata_2025 huggingface dataset:
Research of Soil Biome of a Young Apple Orchard of Intensive Type
Authors: Bondareva E. V. , Seraya L. G. , Larina G. E.
Published: April 2024

Fungi are one of the main sources of biotic inducers of plant immunity, but among this group of microorganisms, the largest number of phytopathogens is also noted. A two-year study was carried out on the dynamics of the composition and structure of the fungal community in the soil and the agrochemical characteristics of the soil of a young apple orchard of intensive type. The study of the fungi pool in the control (background, without plants) showed that the content of soil saprotrophs and cellulolytics was two times higher than the abundance of these groups in the root zone of a young apple tree. The importance of the role of plant exudates for the formation of the root zone mycobiota, its participation in the differentiation of the soil microbial community and the formation of the “phytogenic region” where root exudates affect the activity and distribution of ecological-trophic groups of fungi, is demonstrated. In the zone of intensive root growth in the 10–20 cm layer, a sharp decrease in the content of macroelements (nitrogen, phosphorus, potassium) was noted.
Agrogeochemical Technologies for Managing CO2 Flows in Agroecosystems. Message 1. Management Factors of the Microbial Link of the Agrogeochemical Cycle
Authors: Bashkin V. N.
Published: April 2024

The review considers the application of agrogeochemical technologies aimed at restoring agrogeochemical cycles in agricultural ecosystems, primarily in the microbial link regulating CO2 flows. The factors of management of this microbial link in the application of both mineral and organic fertilizers are shown. The processes of mineralization of soil organic substances and methods of regulation of the conjugate carbon- and nitrogen-mineralizing ability of soils are considered. Changes in the productivity of agricultural ecosystems under conditions of increasing the concentration of carbon dioxide in the atmosphere and in the soil air are considered. Various agrotechnological techniques are shown, including the use of zero tillage, organic fertilizers of various nature, as well as various meliorants, including phosphogypsum. Based on numerous data, it is concluded that agroecosystems in most cases are a pure source of CO2, and sequestration occurs only when agricultural land is transferred to fallow lands. Methods aimed at reducing CO2 fluxes when using fertilizers in the “production–application” cycle are evaluated. It is shown that the existing practice of introducing agricultural low carbon technologies (agricultural low carbon technologies – ALCT) cannot yet indicate their applicability to ensure both food and environmental safety.
Microbiocenosis of Cryofrost Soils in the South of the Vitim Plateau
Authors: Chimitdorzhieva E. O. , Korsunova Ts. D-Ts. , Chimitdorzhieva G. D.
Published: April 2024

The microbial communities in soils of cryomorphoses in the south of the Vitim Plateau have been studied. The objects of study were gley cryoturbated chernozems and humus-quasi-gley carbonated soils. In the course of the study, experimental sites with pronounced cryogenic phenomena were selected. The intensity of microbiological activity was determined by the carbon content of microbial biomass, the number of microorganisms in the dominant groups of microbial communities. Determination of the number of microorganisms in soils was carried out by direct microscopy, which makes it possible to carry out a more accurate count of bacteria in the soil, taking into account adsorbed cells. Cells were preliminarily desorbed on an ultrasonic disperser. The carbon of microbial biomass was determined by the rehydration method. Data were obtained characterizing the direction and intensity of microbiological processes along the horizons of soil profiles of heaving mounds and thermokarst depressions. The number of microorganisms and the dominant groups of bacterial communities of soils formed under the conditions of the ultracontinental climate of Buryatia and relatively close-lying permafrost are presented. It was revealed that bacterial microflora predominates in the soils of heaving mounds and thermokarst depressions. The intra-profile heterogeneity in the distribution of soil microorganisms indicates that, as a habitat, the soil is strongly differentiated in all directions. This differentiation along the vertical of heaving mound and thermokarst depression was reflected in the concept of soil horizons as special ecological niches and the possibility of using microbiological indications of heaving and subsidence occurring during heaving.
Possibilities of Intensification of Spring Wheat Growing Technology in the Western Siberia Forest-Steppe
Authors: Sharkov I. N. , Kolbin S. A. , Vasileva N. V.
Published: April 2024

Based on the results of many years of field experience, an agronomic and economic assessment of the effects of the use of chemicals for spring wheat is given in order to determine the attractiveness for farmers of the transition to growing crops using intensive technology. For the analysis, the prices of chemicals and spring wheat grain that are currently relevant for the Siberian region were taken. It is shown that under the influence of a complex of chemicalization agents (fertilizers, herbicides, fungicide), the average annual yield of wheat in a 4-full grain-pair crop rotation increased 1.8 times, reaching 3.8 tons of grain/ha. The increase in yield by 13% was due to the use of herbicides, 18% – fungicides and 69% – mineral fertilizers with a payback of 1 kg active substance 12.4 kg of grain. When calculating the average per year, the means of chemicalization provided income already at the minimum (from the accepted for analysis) grain price of 10 000 rubles/t. Income increased sharply in a number of field experience options: herbicides, herbicides + fertilizers, herbicides + fertilizers + fungicide. However, when assessing the annual effects, income from chemicals in this series was obtained, respectively, only in 42, 75 and 92% of the years. The probability of losses decreased significantly with an increase in the price of grain. But even at prices of 13.000 and 16.000 rubles/ton, the use of the entire complex of chemicals was unprofitable in 8% of the years due to the severe aridity of the growing season. At current prices for fertilizers and pesticides, the minimum sufficient price of grain can be considered 13.000 rubles/ton, which, however, does not exclude losses in severely dry years.
Replenishment of Humus due to Crop-Root Residues in Flax and Crop Rotations
Authors: Kuzmenko N. N.
Published: April 2024

In the Central region of the Non-Chernozem zone of Russia on sod-podzolic light loamy soil in a long stationary experiment in flax crop rotations, the process of replenishing humus due to crop-root residues was studied. Alternation of crops in the crop rotation in 2004–2011: pure steam – winter rye with sowing of perennial grasses (red clover and timofeevka) – perennial grasses of the 1st year of use – perennial grasses of the 2nd year of use – flax – potato – barley – oats. In 2012–2018, potatoes were excluded from the crop rotation. The contribution of cultivated crops to the accumulation of soil organic matter varied. The largest amount of crop-root residues (6.8 t/ha) remained in the soil after harvesting perennial grasses, which provided a positive humus balance of +1.35 t/ha. In the crop rotation with potatoes without the use of fertilizers, the humus deficit was –0.20 t/ha, with the exclusion of potatoes from the crop rotation, the deficit decreased to –0.05 t/ha per year. The use of fertilizers increased the productivity of crop rotations by an average of 75%, the amount of crop-root residues increased by 10.6 t/ha or 58%, which allowed to obtain a positive balance of humus in the soil. The use of fertilizers at a dose of (NPK)200 (manure 5 t/ha + (NPK)135 and manure 5.7 t/ha + (NPK)120) in an 8-pole crop rotation with pure steam and potatoes when saturated by 25% with perennial grasses provided a humus balance of +0.17 t/ha per year, in 7-full crop rotation with pure steam and without potatoes at saturation by 28.5% with perennial grasses – +0.43 t/ha per year.
Dynamics of Pesticide Use in the Russian Federation
Authors: Mikhaylikova V. V. , Strebkova N. S.
Published: April 2024

Data on the use of pesticides by hazard classes and the use of drugs by chemical classes and active substances from 1990 to 2021 are presented.
Plant Growth and Development Regulators: Classification, Nature and Mechanism of Action
Authors: Tarasov S. S. , Mikhalev E. V. , Rechkin A. I. , Krutova E. K.
Published: April 2024

Questions of the nature and mechanism of action of plant growth and development regulators (hereinafter referred to as regulators) are considered. It is proposed to use the classification of regulators depending on their original nature. Four groups of regulators are distinguished: pure chemicals, physical, biological and complex regulators. Attention is paid to the mechanisms of the relationship of artificial regulators with the natural system of regulation and integration of plants.
Fertilization of Annual Grasses on Gray Forest Soils of the Vladimir Opole
Authors: Okorkov V. V. , Okorkova L. A. , Lebedeva A. E.
Published: April 2024

In a long-term stationary experiment, the effect of fertilizers on the yield of annual grasses (vetch and pea mixtures) and the nitrifying activity of gray forest soils were studied. For 8 years, both without the use of fertilizers and with them, the yield of herbs changed by 1.72–1.88 times. It was found that the use of nitrogen of mineral fertilizers provided 88.3% of the total variation in their yield, the aftereffect of manure – 8.1, the aftereffect of РК fertilizers – 1.8%. For 7 out of 8 years, a high degree of correlation between the yield of grasses and the reserves of N-NO3 in the 0–40 cm layer of soil in the phase of grass germination was revealed. At the same time, the minimum reserves of N-NO3 were formed at a hydrothermal coefficient for the growing season equal to 1.21. The use of fertilizers, increased moisture content and temperatures during the growing season of grasses led to an increase in the nitrification activity of gray forest soil. It is proposed to evaluate the participation of mobile forms of nitrogen in plant nutrition in relation to the content of N-NO3 in the soil to the content of N-NH4 in the water extract (1 : 1). The values of this parameter in the phases of germination and harvesting of grasses confirmed the determining role of N-NO3 reserves in the nutrition of annual grasses. The difference coefficients of the use of nitrogen Naa in doses N60 and N75, which ranged from 40 to 49%, were calculated. An algorithm for calculating the size of the accumulation of N-NO3 during the growing season of grasses is proposed. In nitrogen-fertilized variants, a good coincidence of the utilization coefficients of accumulating N-NO3 reserves with the difference ones has been established.
Impact of Sewage Sludges in Combination with Various Amendments on the Nitrogen State of Leached Chernozem
Authors: Gabbasova I. M. , Garipov T. T. , Dorogaya E. S. , Komissarov M. A. , Nazyrova F. I. , Nigmatzyanov A. S.
Published: April 2024

In a 3 months model experiment, the effect of application of sewage sludge (SS) at doses of 40 and 80 g/vessel (in terms of dry mass corresponds to 5 and 10 t/ha) in combination with straw, kieselguhr and sapropel, on the nitrogen state of leached, slightly eroded chernozem, was studied. It is shown that the addition of kieselguhr and sapropel to SS, unlike of straw, improves the parameters of the soil nitrogen state. A raise of the SS dose leads to a significant increase of the alkaline hydrolysable nitrogen content. The ability of ameliorants with SS to enrich the soil by mineral nitrogen can be arranged in the following descending row: suspended kieselguhr dry kieselguhr sapropel SS severally straw. A double dose of SS does not differ significantly from a single dose in terms of its influence on the contents of total and mineral nitrogen, humification and soil acidity; the use of high doses of SS is rational for waste disposal.
Physic-Chemical Characteristics of Organo-Clay Complexes of Agrochernozems of Different Localization on the Slope
Authors: Tsomaeva E. V. , Artemyeva Z. S. , Zasukhina E. S.
Published: April 2024

Organo-clay complexes of agrochernozems of different localization on the slope were studied, including by the method of dynamic light scattering (DLS). A decrease in the concentration of organic carbon (Corg) of silty fractions in the arable horizons of washed-out agrochernozems was revealed, which was a consequence of the constant exposure of the soil mass of the underlying horizon, provoking the decomposition of organic matter(s). This was accompanied by changes in the content of non-silicate iron (Fed) as a result of oxidative degradation of organo-iron complexes, which contributed to the desorption of Fed. Different intensity of erosion processes influenced the tendency to change the dynamics of Fed: a lower slope steepness (4°) contributed to an increase in the load of Corg on iron oxides, resulting in an increase in iron desorption, whereas in conditions of greater steepness (6°), a decrease in iron desorption was observed. Regardless of the position on the slope, the highest values of the average diameter of organo-clay complexes (D) were observed in the upper horizons of the studied agrochernozems, which decreased down the profile. As a result of erosion processes, the size of organo-clay complexes in arable horizons decreased in comparison with that in non-eroded agrochernozems (by 1.1 times). It was revealed that the size of organo-clay complexes in the studied agrochernozems was determined by the values of the content of Corg and Fed, although the degree of their significance differed in the upper humus (Aarable, A1, AB) and lower (B, C) horizons. In the upper horizons, the value of D was determined by the content of Corg, whereas in the lower horizons, the main role in the formation of the size of organo-clay complexes belonged to Fed. The obtained data allowed us to assume a more significant role of organic matter (OM) in the aggregation of cley particles compared to that of Fed. The hypothesis of a multiple linear regression dependence of the value of D on the values of the concentration of carbon (Corg and Ccarbonates) and Fed in them turned out to be statistically significant both for the entire set of genetic horizons and for humus horizons The coefficient of determination of the model (R2) increased in a row: 0.578 (Apl + A1) 0.678 (Apl + A1 + AB + B + BC + C) 0.724 (Apl + A1 + AB) 0.983 (AB).
Payback of Phosphorus, Taking into Account Its Long-Term Aftereffect
Authors: Volynkina O. V.
Published: April 2024

In a 52-year stationary experiment at the Central Experimental Field of the Kurgan Research Institute, the effect and aftereffect of phosphorus fertilizer against the background of nitrogen application were studied. A dose of P40 in combination with nitrogen, introduced for 25 years in the corn–two wheat–oats crop rotation (in the amount of P1000), after discontinuation of use, had a long aftereffect in sowing permanent wheat after stubble. In the experiment, the economic efficiency of the action and aftereffect of a dose of phosphorus P1000 was evaluated. Taking into account the 27-year aftereffect, the payback of the phosphorus dose of P40 added to N40–50 increased from 9.0 to 15.5 kg/kg.
Features of Dynamics and Instability of Plasma Jets Expanding into an External Magnetic Field in Laboratory Experiments with Compact Coaxial Plasma Generators on a Large-Scale “Krot” Stand
Authors: Korobkov S. V. , Nikolenko A. S. , Gushchin M. E. , Strikovsky A. V. , Zudin I. Yu. , Aidakina N. A. , Shaikhislamov I. F. , Rumenskikh M. S. , Zemskov R. S. , Starodubtsev M. V.
Published: April 2024

Structural instabilities that develop during pulsed injection of dense plasma jets into vacuum in the presence of an external quasi-homogeneous magnetic field are studied by high-speed photography using ICCD cameras. The experiments are carried out in the chamber of the “Krot” stand, which has record-breaking dimensions in its class of installations (diameter—3 m, length of the working section—10 m), and makes it possible to study plasma dynamics by various diagnostic methods at scales of more than 1 m both along the magnetic field and in the direction transverse to the magnetic field. During injection along the magnetic field, a transverse collimation of the flow of ionized matter and the development of a flute instability of the plasma boundary are observed, which, at the late stages of expansion, leads to the plasma leaving the injection region in the form of several jets across the field. During transverse injection, the formation of a collimated flow, a “plasma sheet,” is observed, in which, as the plasma moves across the field, inhomogeneous structures develop in the direction of injection.
Precision Measurements of X-Ray Spectra for the Diagnosis of Laboratory Astrophysical Plasma
Authors: Ryazantsev S. N. , Skobelev I. Yu. , Kuznetsov A. P. , Kulikov R. K. , Pikuz S. A.
Published: April 2024

A technique is described for achieving high accuracy (relative error up to ≈0.001%) for measuring the absolute wavelengths of the spectral lines of multiply charged ions with an average (Z = 17–25) by the nuclear charge, the spectra of which can be used for plasma diagnostics in laboratory astrophysics experiments. It is based on irradiation with subnanosecond laser pulses with an intensity of 1015–1016 W/cm2 targets with a multicomponent chemical composition, including atoms with both medium and low Z. The presence of the latter ensures the presence in the emission spectrum of the resulting laser plasma of lines of hydrogen-like ions used as references. An atomic-kinetic code was created, and the intensities of possible reference and investigated spectral lines were calculated. The principles of selecting the target material, the features of the implementation of the technique on the example of a focusing spectrometer with spatial resolution based on spherically curved mica and α-quartz crystals are considered, and specific parameters of spectrometer circuits and types of targets for precision measurement of the wavelengths of spectral lines of helium- and lithium-like ions with nuclear charges Z = 13–25 are given. The results obtained in this work will be used in the planning of fundamental X-ray spectral studies at the ELF laser facility being developed at MEPhI.
Eliminating the Hubble Tension in the Presence of the Interconnection between Dark Energy and Matter in the Modern Universe
Authors: Bisnovatyi-Kogan G. S. , Nikishin A. M.
Published: April 2024

It is accepted in modern cosmology that the scalar field responsible for the inflationary stage of the early Universe is completely transformed into matter. It is assumed that the accelerated expansion is currently driven by dark energy (DE), which is likely determined by Einstein’s cosmological constant, unrelated to the scalar field responsible for inflation. We consider a cosmological model in which DE can currently have two components, one of which is Einstein’s constant (Λ) and the other, smaller dark energy variable component DEV (ΛV), is associated with the remnant of the scalar field that caused inflation after the main part of the scalar field has turned into matter. We consider only the stages of evolution of the Universe after recombination (z=1100), where dark matter (DM) is the predominant component of matter. It is assumed that the transformation of the scalar field into matter continues at the present time and is accompanied by the reverse process of the transformation of DM into a scalar field. The interconnection between DM and DEV, which leads to a linear relationship between the energy densities of these components after recombination ρDM=αρDEV, is considered. Variants with a dependence of the coefficient α(z) on the redshift z are also considered. One of the problems that have arisen in modern cosmology, called Hubble Tension (HT), is the discrepancy between the present values of the Hubble constant (H0) measured from observations of the Universe at small redshifts (z≲1) and the values found from fluctuations of the cosmic microwave background in the Universe at large redshifts (z≈1100). In the model under consideration, this discrepancy can be explained by the deviation of the existing cosmological model from the conventional Λ cold dark matter (CDM) model of the flat Universe by the action of the additional dark energy component DEV at the stages after recombination. Within this extended model, we consider various α(z) functions that can eliminate the HT. To maintain the ratio of DEV and DM energy densities close to constant over the interval 0⩽z≲1100, it is necessary to assume the existence of a wide spectrum of dark matter particle masses.
Neutrino Spectra of Magneto-Rotational Supernovae and Observations Using Large-Volume Telescopes
Authors: Kondratyev V. N. , Cherubini S.
Published: April 2024

The dynamics of neutrinos in hot and dense magnetized matter, corresponding to a magneto-rotational explosion of supernovae, is considered. It is shown that the effective collisions of neutrinos in a magnetized nucleon gas, due to the Gamow–Teller component of the neutral current, change from exo- to endo-energetic scattering, when the neutrino energy becomes approximately four times higher than the temperature of the substance. Correspondingly, the energy transfer cross section in the neutrino kinetics changes from positive to negative values under these conditions. For realistic parameters of supernovae, the considered effects lead to an increase in the hardness of the neutrino spectra. The possibilities of detecting supernova neutrinos by large-volume observatories KM3NeT and Baikal-GVD are discussed.
Analysis of the Parameters of Radio Pulsars with Giant Pulses Using the Principal Component Analysis
Authors: Malov I. F. , Malov O. I.
Published: April 2024

Clustering of radio pulsars with observable giant pulses (GPs) has been carried out using the principal component analysis. Five parameters were used (period, its derivative, observed luminosity, kinematic age, and the angle between the rotation axis and the magnetic moment of the central neutron star). It was shown that the set of all known GP pulsars is divided into two clusters in the phase space of the principal components. One of the clusters contains four pulsars with short periods and high luminosity; the second cluster contains nine long-period and fainter sources. A separate object, not included in these two clusters, is the pulsar in the Crab Nebula. Possible models that could explain the observed difference between GP pulsars were considered.
Adiabatic Radio Emission Spectrum of the Sun’s Coronal Holes
Authors: Dravskikh A. F. , Dravskikh Yu. A.
Published: April 2024

Coronal holes on the Sun have been observed at individual frequencies for quite a long time in the wavelength range from radio to X-rays. Observations in a wide range of radio frequencies are carried out with the RATAN-600 radio telescope. An analysis of long-term spectral observations of the RATAN-600 radio telescope showed that the emission spectrum of coronal holes is radically different from the spectrum of active formations above sunspots, but, differing markedly from the spectrum of the quiet Sun, it also has similarities with it. It has been established that the radio emission of coronal holes has an adiabatic spectrum and does not contain noticeable coherent radiation, that is, recombination radio lines and lines of the fine structure of hydrogen and other elements.
Regular Chains of Star Formation Regions in Spiral Arms and Rings of Disk Galaxies
Authors: Gusev A. S.
Published: April 2024

The regularity in the distribution of young stellar groups along the spiral arms of galaxies, first discovered by Bruce and Debra Elmegreen in 1983, was considered a rather rare phenomenon. However, recent studies of the spatial regularities in the distribution of the young stellar populations along the arms of the spiral galaxies NGC 628, NGC 895, NGC 4321, NGC 5474, NGC 6946, as well as along the rings of the spiral galaxy NGC 6217 and the lenticular galaxy NGC 4324, have revealed that this spatial (quasi) regularity and/or the presence of regular chains of star-forming regions is a fairly common phenomenon. Across all galaxies, the characteristic regularity scale is 350–500 pc or a multiple thereof. It should be noted that theoretical models predict an instability scale of a stellar-gas disk on the order of a few kpc, which is several times larger than what has been observed. The paper is partly based on the report presented at the Modern Stellar Astronomy 2022 Conference held at the Caucasian Mountain Observatory of the Sternberg Astronomical Institute, Moscow State University, on November 8–10, 2022.
Comparison of Instabilities of Annular Perturbations on the Background of Pulsating 2D and 3D Self-Gravitating Models
Authors: Mirtadjieva K. T. , Nuritdinov S. N.
Published: April 2024

The problem of gravitational instability of the observed annular (ring-like) structural perturbation modes on the background of a nonlinearly pulsating spherical model based on the well-known equilibrium Camm ball is studied. Nonstationary analogues of dispersion relations for the perturbation modes under consideration within this model are obtained. Critical diagrams of the initial virial ratio versus the model rotation parameter are constructed for each case. A comparative analysis of the increments of gravitational instability of annular perturbation modes on the background of spherical and disk-shaped nonlinearly pulsating models is also performed. An analysis of the results shows that the annular perturbation modes are predominantly more unstable in a nonstationary disk than in a spherical nonequilibrium model, regardless of the rotation parameters and the initial virial ratio of the systems. The article is partly based on a report presented at the conference “Modern Stellar Astronomy-2022” held at the Caucasian Mountain Observatory of the Sternberg Astronomical Institute of Lomonosov Moscow State University, November 8–10, 2022.
Mass Computations of the Brightness of Stars in an Arbitrary Spectral Band
Authors: Prokhorov M. E. , Zakharov A. I. , Moshkalev V. G. , Krusanova N. L. , Tuchin M. S.
Published: April 2024

The problem of calculating the brightness of an array of stars in an arbitrary photometric band, which is not the standard band of astronomical photometry, is considered from their multicolor photometry in some other photometric system. A similar problem is to transfer photometric measurements of stars from one multicolor photometric system to another. This task includes methods for calculating and comparing magnitudes, as well as merging photometric catalogs. The questions of choice of various zero-points of photometry and reduction of measurements for the atmosphere are considered. The issues of reducing the error of the proposed methods are discussed. The article is partly based on a report presented at the conference “Modern Stellar Astronomy-2022”, held at the Caucasian Mountain Observatory of the Sternberg State Astronomical Institute, Moscow State University, in November 8–10, 2022.
Orbital Period Variations of the Eclipsing Binaries RX Ari and V449 Oph
Authors: Khaliullina A. I.
Published: April 2024

The variations in the orbital period of the eclipsing binaries RX Ari and V449 Oph have been analyzed. It has been shown that the variations in the period of RX Ari can be represented by a superposition of a secular period increase and two cyclic variations. The secular increase in the period can be explained by the exchange of matter between the components. Cyclic variations in the period may be due to the presence of two additional bodies in the system, or only one additional body in combination with the magnetic activity of the main component. The variations in the orbital period of V449 Oph can be represented with almost equal accuracy either as a superposition of two cyclic variations, or as a superposition of a secular period increase and two cyclic variations. The obtained parameters of the light-time effects and magnetic quantities lead to the conclusion that it is preferable to use linear elements to represent the variations in the orbital period of V449 Oph. In this case, one of the cyclic variations can be a consequence of the light-time effect, and the second one can be a consequence of the magnetic activity of the secondary component. Both types of variations can also be a consequence of the magnetic activity of the secondary component.
THE ACTIVITY OF A SOLAR-TYPE STAR TOI-1422 AND MASS LOSS OF THE ATMOSPHERE OF THE PLANET TOI-1422b
Authors: Savanov I. S.
Published: April 2024

The results of the analysis of the activity of a solar type star G2V TOI-1422 are presented and estimates of the loss of atmospheric matter of the planet TOI-1422b are made. The planet can be attributed to the type of hot neptunes. Compared to other exoplanets of a similar mass range it is expected that the planet has an extensive gas envelope. According to the long-term photometric survey of Kamogata Wide-field Survey (KWS) the TOI-1422 activity was analyzed and the existence of possible activity cycles of 1650-1680 days and 2450 days was suggested. The probable value of the rotation period P of the star lies in the range of 27 (+19, –8) days, observations of the KWS survey in the V filter indicate the most possible value for P = 32 days. Mass loss of the planet’s atmosphere is determined using an approximation formula corresponding to the model of atmospheric loss with an energy restriction. To estimate the flux of XUV photons analytical dependences were used linking the flux values and the parameter \(\log R_{{{\text{HK}}}}^{'}\). Calculations have shown that the mass loss of TOI-1422b is \(\dot {M} = 9.4 \times \) 108 g/s and taking into account the existing errors in determining the parameters of the atmosphere it lies in the range from 6.8 × 108 g/s to 1.4 × 109 g/s.
EVOLUTION OF THE X-RAY BINARY SYSTEM Sco X-1
Authors: Fedorova A. V. , Tutukov A. V.
Published: April 2024

The possible evolution of a bright low-mass X-ray binary system Sco X-1 is numerically investigated within the framework of a model assuming that the donor of the system (a satellite of a neutron star) fills its Roche lobe. The calculations take into account a strong induced stellar wind (ISW) of the donor, which occurs due to irradiation by hard radiation of an accreting relativistic star. At the same time, using the example of Sco X-1, three hypotheses are investigated, within the framework of which a high rate of mass exchange can be obtained for semi-separated X-ray binary stars. The first hypothesis is the presence of a strong ISW of the donor with standard magnetic braking. Calculations have shown that in this case it is possible to obtain a high rate of mass exchange, but at the same time the donor cannot fill the Roche lobe – it “goes under it”. The second hypothesis is an increase of magnetic braking, that is, an increase of the loss of angular momentum from the system due to the magnetic stellar wind of the donor (MSW). Such an amplification may be associated with the intense ISW of the donor in the presence of a strong magnetic field. Numerical modeling shows that with an increase of MSW by ~20 times, a high rate of mass exchange is possible when the donor fills the Roche lobe. The third hypothesis suggests the possibility of canceling the direct exchange of angular momentum between the orbital moment of the system and the moment of accreted matter passing from a low-mass donor to a more massive accretor. With such cancellation, the main process, increasing the semi-axis of the orbit, disappears. Calculations show that in this case it is possible to obtain a sufficiently high rate of mass exchange. However, the most likely reason for the increase of the rate of mass exchange in low-mass X-ray binary systems is probably the increase of magnetic braking.
THE NEAR INFRARED AND OPTICAL PHOTOMETRIC ACTIVITY OF V517 Cyg
Authors: Efimova N. V. , Grinin V. P. , Arkharov A. A. , Potravnov I. S. , Melnikov S. Yu. , Larionov V. M. , Klimanov S. A. , Gorshanov D. L.
Published: April 2024

A near infrared and optical photometric study of Herbig star V517 Cyg has been carried out. Infrared data were obtained in 2003–2017 at the Campo Imperatory Observatory (Italy) with the Pulkovo telescope AZT-24 in Johnson’s \(JHK\) bands. Optical light curves in Johnson \(UBVR\) bands were obtained at the Maidanak observatory. Additional optical photometry from different sources (ASSAS, WISE, and AAVSO) was also used. It was shown that the behavior of V517 Cyg in the near infrared is typical for UX Ori stars. A considerable contribution to the near infrared variability is due to variable extinction along the line of sight, but the disk radiation becomes strong in the \(H\) and \(K\) bands: there is a significant correlation of \(V\) and \(J\) magnitudes (\(r \sim 0.84\)), while \(H\) and \(K\) bands correlates poorly with \(V\) band. The amplitude of variability in \(J\) is quite large (\( \sim {\kern 1pt} {{1.8}^{m}}\)). The deepest minimum (\(\Delta V \sim {{3.6}^{m}}\)) in the \(V\) band demonstrates quasi-periodic variations with an amplitude of \( \sim {\kern 1pt} {{0.8}^{m}}\) and a period of \( \sim {\kern 1pt} 19\) days, the origin of which is still unclear. It is possible that these quasi-periodic variations are related to rotation period of a second companion, a cold T Tauri star. The spectrum V517 Cyg reveals typical for UX Ori stars the double-peaked emission line Hα. The NaI D doublet has inverse P Cyg profiles, indicating intense accretion of gas onto the star. The accretion rate from an equivalent width of the Hα line is \({{\dot {M}}_{{acc}}} = 3.6 \times {{10}^{{ - 8}}}\,{{M}_{ \odot }}\) per year.
STATISTICS OF THERMAL PLASMA PARAMETERS AND NON-THERMAL X-RAY SPECTRA OF SOLAR FLARES WITH HELIOSEISMIC RESPONSE
Authors: Sharykin I. N. , Zimovets I. V. , Kosovichev A. G.
Published: April 2024

We present the results of statistical analysis of various thermal plasma parameters and non-thermal X-ray spectra of helioseismically active (producing “sunquakes”) solar flares of the 24th solar cycle up to February 2014. Two samples of flares are compared: with helioseismic activity in the form of sunquakes and a sample of flares without photospheric disturbances. The dependences of the considered flare parameters on the energy of helioseismic disturbances are also investigated. Quantitative parameters of solar flares are taken from the statistical work of the Global Energetics series by Markus Ashwanden in 2014–2019. We consider thermodynamic plasma parameters derived from the analysis of RHESSI X-ray spectra and differential emission measure (from AIA EUV images), as well as the characterization of non-thermal X-ray spectra from RHE-SSI. Statistical analysis confirmed that helioseismically active solar flares are characterized by significantly larger fluxes of non-thermal X-ray emission compared to flares without photospheric perturbations. A good linear relationship between helioseismic energy and the total flux of non-thermal X-ray radiation and the total energy of accelerated electrons is found. It is shown that the power-law index of the nonthermal X‑ray spectrum is not the parameter by which one can separate the two groups of flares under consideration. The analysis of the X-ray thermal spectra shows a slight difference between the flares with the sunsets.
GRAVITATIONAL CAPTURE AS A POSSIBLE SCENARIO ORIGIN OF THE MOON
Authors: Tutukov A. V. , Dremova G. N. , Dremov V. V.
Published: April 2024

The article is devoted to the problem of the origin of the Moon. Discussed modern scenarios for the formation of the Earth-Moon system: simultaneous formation of the Earth and the Moon in the circumsolar gas of dust disk; impact partial destruction of the Earth by a massive asteroid; gravitational capture of the Moon by the Earth; destruction of the double moon at the beginning when approaching the Earth with possible subsequent absorption components of smaller mass by the Earth. We offer two-stage scenario of gravitational capture of the Moon by the Earth in the early stages Solar system. In the first stage, using a hybrid numerical model in the formulation of the three-body problem (Sun, Earth and Moon) and N-bodies, the search and selection of temporary orbits of the Moon around the Earth is carried out. Using the backward integration method in the formulation N-body problem, the influence of tidal forces on pumping of orbital moment of the Moon (\(P_{{{\text{orb}}}}^{M}\)) relative to the Earth at its own moment \(P_{s}^{M}\) is estimated. As the simulation shows, actions tidal forces alone are not enough to capture the Moon by the Earth in a short time time scale \( \sim 100\) years (\(\Delta P_{s}^{M} \sim {{10}^{{ - 6}}}P_{{{\text{orb}}}}^{M}\)). At the second stage, the factor is taken into account viscous-dissipative environment leading to additional “slowing down” of the Moon, due, for example, to collisions with asteroids and the transition of tidal energy into heat, which helps the Moon get rid of excess kinetic energy and gain constant orbit around the Earth.
SPECTRAL SURVEY OF THE STAR FORMATION REGION DR21OH IN THE 4-mm WAVELENGTH RANGE
Authors: Kalenskii S. V. , Mikheeva E. A.
Published: April 2024

The results of a spectral survey of the star-forming region DR21OH in the 4 mm wavelength range are presented. Sixty-nine molecules and their isotopologues have been detected, ranging from simple diatomic or triatomic molecules, such as SO, SiO and CCH, to complex organic species, such as CH3OCHO or CH3OCH3. A noТаблица part of the results qualitatively repeat the results of the survey of the same source at 3 mm. The inventories of molecules found at 3 and 4 mm overlap to a great extent. However, at 4 mm we found a number of species that have no allowed transitions in the 3 mm wavelength range, e.g. DCN, DNC, or SO+. The bulk of the molecules detected at 4 mm are those that are common for dense cores, e.g., HC3N or CH3CCH, but some of the detected molecules are typical for hot cores. The latter include complex organic molecules CH3OCHO, CH3CH2OH, CH3OCH3, etc. However, the detected emission of these molecules probably arise in a gas heated to 30 K only. Nine molecules, including complex species CH3C3N, CH3CH2CN, CH3COCH3, were found by spectral line stacking. This demonstrates the prospects of the method for the study of molecular clouds.
RADIATIVE TRANSFER: ASYMPTOTIC SOLUTION OF THE KINETIC EQUATION OF RADIATION PROPAGATION, N-th ORDER ASYMPTOTIC APPROXIMATION AND IMPROVED BOUNDARY CONDITIONS
Authors: Serov S. A. , Serova S. S.
Published: April 2024

In the article, new asymptotic approximation of the \(n\)-th order is obtained and proposed to be used in calculations of radiation propagation in optically thick media without scattering; the asymptotic approximation is simpler and more precise than the known diffusion approximation. It is shown, that for optically thick media the asymptotic solution of the kinetic equation of radiation propagation without scattering is asymptotic expansion of the exact integral solution of that kinetic equation. The rigorous derivation of the diffusion approximation equation is obtained. Improved boundary conditions, which are essential for practical application in calculations of radiation propagation, are derived.
SIMULATIONS OF LINEAR POLARIZATION OF PRECESSING AGN JETS AT PARSEC SCALES
Authors: Todorov R. V. , Kravchenko E. V. , Pashchenko I. N. , Pushkarev A. B.
Published: April 2024

The latest results of the most detailed analysis of multi-epoch polarization-sensitive observations of active galactic nuclei (AGN) jets at parsecs scales by very long baseline interferometry (VLBI) reveal several characteristic patterns of linear polarization distribution and its variability [1, 2]. Some of the observed profiles can be reproduced by a simple model of a jet threaded by a helical magnetic field. However, none of the models presented to date can explain the observed polarization profiles with an increase in its degree towards the edges of the jet, and accompanied by a “fountain” type electrical vector pattern and its high temporal variability in the center. Based on simulations of the VLBI observations of relativistic jets, we show here that the observed transverse linear polarization profiles, atypical for the simple magnetic field models can be naturally produced assuming the finite resolution of VLBI arrays and precession of a jet on ten-years scales, observational indications of which are found in an increasing number of AGN. In our simulations, we qualitatively reproduce the distribution of the electric vector and its variability, though the polarization images are characterized by a bright spine due to weak smearing, which is poorly consistent with observations. More effective depolarization can be obtained in models with the suppressed emission of the jet spine.
Study on the interaction mechanism between ficin and a graft copolymer of carboxymethyl cellulose sodium salt and N-vinylimidazole using moleculardocking, fourier-transform infrared spectroscopy and raman spectroscopy
Authors: Sorokin A. V , Goncharova S. S , Lavlinskaya M. S , Holyavka M. G , Zuev Yu. F , Faizullin D. A , Kondtatyev M. S , Artyukhov V. G
Published: April 2024

Flexible molecular docking, Fourier-transform infrared spectroscopy (FTIR) and Raman spectroscopy were used to investigate the interaction mechanism between ficin and a graft copolymer of carboxymethyl cellulose sodium salt and N-vinylimidazole. Functional groups and fragments of the graft copolymer as well as amino acid residues that form primary structure of enzyme and participate in interactions between ficin and a graft copolymer are identified. It is shown that Raman spectroscopy yields more complete information about graft copolymer fragments interacting with the protein than that FTIR can provide. It is found that the amino acid residues that form the active site of ficin are involved in the formation of hydrogen bonds and hydrophobic interactions with the graft copolymer leading to an increase in the proteolytic activity of the conjugated enzyme.
Stability of collagen gel after uv irradiation
Authors: Nashchekina Yu. A , Trusova N. A , Nikonov P. O , Nashchekin A. V , Mikhailova N. A
Published: April 2024

Type I collagen is the most abundant extracellular matrix protein in the human body, as well as is the main structural element in tissues and regulates cellular functions. In lifetime, the organism and extracellular matrix components such as collagen are exposed to UV irradiation. The purpose of this work was to study the effect of UV irradiation on the stability and structure of collagen fibrils. It has been shown that UV irradiation has a stabilization effect on collagen gel at a concentration of 0.5 mg/ml. Scanning electron microscope images have shown that the diameter of the collagen fibrils is not changed after UV irradiation. The degree of spreading of cells cultured on collagen fibrils after UV irradiation is greater compared to those cultured on collagen fibrils unirradiated with UV light. UV irradiation promotes a shift of the collagen amide A band to lower frequency, indicating that it induces structural changes in collagen.
A toolbox for visualization of sequencing coverage signal
Authors: Bezdvornykh I. V , Cherkasov N. A , Kanapin A. A , Samsonova A. A
Published: April 2024

Whole genome sequencing data allow access not only to information about genetic variation, but also provide an opportunity to evaluate the overall genome stability. Sequencing coverage signal considered as the number of fragments alligned to a given region within the genome can be used as a trustworthy source of data both on discovery of genomic rearrangements and the current state of whole genome sequencing as well as on precision of structural variant predictions by computational algorithms. The latter is of utmost importance as conflicting data on gene rearrangement events obtained by tools for finding gene rearrangements often appear. However, until recently, validation of predicted variants may present a significant challenge mainly due to the lack of information sources that may assist researchers with direct work with coverage signals and signal visualization with high precision. The present study proposes Sequence COverage ProfilEs (SCOPE), a prototype toolset that includes databases, web-interface and a series of programs for the processing of sequencing data, visualizing and storing of signal coverage profiles. The computer platform and interface is equipped with open-source software, supports local host deployment and allows users to process and analyze their own sequencing data.
Melting calorimetry of rat liver nuclei in the presence of magnesium ions
Authors: Kolomijtseva G. Ya , Prusov A. N , Kolomijtseva E. A , Smirnova T. A
Published: April 2024

Differential scanning calorimetry was used to determine thermodynamic parameters of decondensation of intranuclear rat liver chromatin was induced by a decrease in the concentration of magnesium ions from 5 mM to 0 mM. The process of chromatin melting in the temperature range of 70-100°C occurs in the following order: melting of core-histones, melting of relaxed DNA, and melting of topologically constrained DNA. It was found that Tm and Д H of individual peaks also depend on the concentration of Mg2+ ions in the buffer. In nuclei with condensed chromatin, Mg2+ ions at a concentration of 5 mM increased significantly the Tm of core histones (by ~7°C), as compared to that in unfolded chromatin but at the same time lowered the Tm of nuclear DNA both in the relaxed and constrained state (by ~2.5°С and ~7.5°С, respectively). In the presence of Mg2+ ions, melting enthalpy for peaks increased significantly. At the same time, a decrease in molecular weights of intranuclear DNA levels out a stabilizing effect of Mg2+ ions on core histones. A rise in the concentration of Mg2+ ions above 5 mM leads to the appearance of a new peak with Tm above 100°С, which probably reflects the thermal behavior of some Mg-induced aggregates. Possible mechanisms underlying thermal behavior of chromatin inside the nucleus are discussed.
Influence of alginate-fabric coating with silver nanoparticles on the course of wound process in laboratory animals
Authors: Malyshko V. V , Fedulova L. V , Sokolov M. E , Moiseev A. V , Basov A. A , Dorohova A. A , Shashkov D. I , Dzhimak S. S
Published: April 2024

Alginates with various modifying additives (for example, chitosan) and various methods of physical treatment are used in the design of prototypes of innovative wound dressing. The aim of this study was to create and explore the properties of a prototype of textile-based sodium alginate wound dressing containing silver nanoparticles subjected to10 freeze cycles, and to evaluate its efficacy on the course of the purulent wound process in rats. The study showed that the developed technology of 10-fold cyclic freezing makes it possible to significantly increase the amount of silver nanoparticles in the composition of textile-based sodium alginate wound dressing, primarily due to silver nanoparticles that have a diameter not larger than 15 nm, and are characterized by the highest antibacterial activity. The use of the developed wound dressing with silver nanoparticles reduces metabolic disturbances when the nonspecific defense system response occurs in the wound tissue; on the 3rd and 5th day after wounding less pronounced changes in free radical oxidation indices were found, the levels of antioxidant defence enzymes (catalase and superoxide dismutase) in wound tissue were lower than those observed after the use of wound dressing with silver nanoparticles, but not containing alginate, or after wound debridement without alginate or nanoparticles done every day.