bluuebunny/crossref_metadata_2025 huggingface dataset:
The Magnetoelastic Properties of Spin Valves
Containing CoFe/Dy Layers
Authors: Naumova L. I. , Zakharov A. A. , Milyaev M. A. , Bebenin N. G. , Zavornitsyn R. S. , Maksimova I. K. , Proglyado V. V. , Ustinov V. V.
Published: April 2024

Spin valves containing a Dy layer have been formed on an elastic polyimide film by magnetron sputtering. The field dependences of the magnetoresistance of samples subjected to different tensile deformations have been measured. The character of the variations of the magnetoresistive properties of a spin valvesubjected to tensile deformation is shown to depend on the thickness of the dysprosium layer. In particular, the thickness of the dysprosium layer affects the maximum relative elongation at which the magnetoresistanceof spin valves remains unchanged.
Predicting the Concentration Dependence of the Surface Tension
of Ternary Systems
Authors: Dadashev R. Kh. , Elimkhanov D. Z. , Khazbulatov Z. L.
Published: April 2024

A comparative analysis of semi-empirical methods based on the Kohler, Bonnier, and Toop models for predicting the surface tension (ST) of ternary systems has been performed. Surface tension–concentration dependence calculations have been carried out in the indium–tin–lead and indium–tin–gallium systems. The ternary indium–tin–lead system is characterized by the fact that the excess surface tension isotherms of all the side binary melts are symmetrically shaped with respect to the equimolar composition, and such systems are called symmetric. In the ternary indium–tin–gallium system, the excessive surface tension isotherms of side binary indium–gallium and tin–gallium systems have pronounced asymmetry with respectto the equimolar composition, and such systems are called asymmetric. It has been shown that a method based on the Kohler model rather precisely describes the concentration dependence of the surface tension ofsymmetric ternary systems. However, this method does not predict the concentration dependence of the surface tension of asymmetric systems. It has been revealed that the Bonnier and Toop models can predict thesurface tension–concentration dependence for asymmetric ternary systems with strong asymmetry in the excess surface tension isotherms of two side binary systems independently of the degree of complexity in these isotherms within overall error of experiment.
ULTRASONIC METHOD FOR SURFACE TREATMENT OF ANISOTROPIC ELECTRICAL STEEL TO REDUCE ITS TOTAL MAGNETIC LOSSES FOR MAGNETIZATION REVERSAL
Authors: Tiunov V. F.
Published: April 2024

The paper describes an ultrasonic method for the formation of locally deformed zones (LDZ) in the form of mechanical scratches applied to the surface of anisotropic electrical steel of nuclear power plants to crush its domain structure in order to reduce the total magnetic losses Р. It is shown that, as a result of such processing, using the example of a 3407 type steel, the value of P decreases by an average of 10-15%. It has been established that exposure to ultrasound leads to a significant increase in the rate of scratching.
THERMAL STABILITY OF CAST CONDUCTOR MICROALLOYED ALUMINUM ALLOYS
Authors: Komelkov A. V. , Nokhrin A. V. , Bobrov A. A. , Shvetsova A. A. , Sakharov N. V. , Faddeev M. A.
Published: April 2024

The nucleation of the Al3X (X = Zr, Yb, Er, Hf) particles in the cast conductor Al alloys including the alloys additionally doped with Mg and Si was studied. The alloys were made by induction casting. To investigate the particle nucleation kinetics, the specific electrical resistivity (SER) and microhardness measurements were applied. It was shown that the investigated alloys can be subdivided into three groups. Group I includes the alloys, which the decrease in the SER with increasing annealing temperature takes place in due to the particle nucleation. Group II includes the alloys, which the particle nucleation takes place in during the bulk crystallization. The SER magnitude of such alloy was close to the SER of pure Al. The SER of the alloys of Group III almost doesn’t change during annealing and is 3.0-3.4 ·cm that evidences a high alloy solid solution stability. Using Jonhnson-Mehl-Avrami-Kolmogorov equation, the particle nucleation kinetics in the Group I alloys was analyzed. The activation energy of the particle nucleation in the Group I alloys was found to be close to the activation energy of volume diffusion, but the values of the decomposition intensity coefficient (n = 0.5-0.8) in Johnson-Mehl-Avrami-Kolmogorov equation appeared to be smaller that the theoretical value n = 1.5 typical for the particle nucleation inside the bulk crystal lattice. This contradiction was related to the presence of large primary or eutectic Al3X particles in the alloy structure. The Al-0.25%Zr-0.25%Er-0.15%Si alloy was shown to have the optimal set of properties: the characteristics of this alloy after annealing match the requirements to the alloys being developed: SER less than 2.95 ·cm, microhardness Hv ~ 550 MPa.
The Electrical Resistivity, Magnetic, and Galvanomagnetic
Properties of a Cast and Rapid Melt Quenched Mn3Al Heusler Alloy
Authors: Marchenkov V. V. , Irkhin V. Yu. , Semiannikova A. A. , Korenistov P. S. , Marchenkova E. B.
Published: April 2024

The electrical resistivity, magnetic, and galvanomagnetic properties of the cast and rapid melt quenched Mn3Al Heusler alloy have been studied. Rapid melt quenching was found to result in changing the microstructure of the Mn3Al alloy, which leads to substantial changes in its electronic transport and magneticproperties. It was suggested that for the cast and rapid melt quenched Mn3Al alloy frustrated antiferromagnetic and almost compensated ferrimagnetic state could appear, respectively. It is shown that the preparation and treatment of the Mn3Al compound plays a substantial role in the formation of its electronic and magneticcharacteristics
The Electronic Structure and Optical Properties
of Heusler Alloys Mn2 – xFe1 + xAl (x = –0.5, 0, 0.5, 1)
Authors: Shreder E. I. , Lukoyanov A. V. , Mukhachev R. D. , Filanovich A. N. , Dash Shubra , Patra A. K. , Vasundhara M.
Published: April 2024

In this paper, we present the calculation results of the electronic structure and optical spectrumand an experimental study of the optical properties of Heusler alloys Mn2 – xFe1 + xAl (x = –0.5, 0, 0.5, 1).An anomalous for metallic systems behavior of the optical conductivity of alloys in the IR region of the spectrumwas found: the absence of Drude growth and a high level of interband absorption. This behavior is shownto be determined by the features of the electronic structure: the Fermi level is located in the region of highdensity of states that is formed by the d states of Mn and Fe.
Formation of Chemical Short-Range Order in Equiatomic CoNiCrFeMn High-Entropy Alloy. Atomistic MD/MC Simulation
Authors: Karkin I. N. , Karkina L. E. , Gornostyrev Yu. N.
Published: April 2024

Abstract—The formation of short-range order in the equiatomic high-entropy alloy (HEA) CoNiCrFeMn during annealing at moderate temperatures was studied using atomistic MD/MC simulation, including the exchange of atoms in the Monte Carlo (MC) scheme and the relaxation of its positions by the molecular dynamics (MD) method. It has been found that two types of chemical short range order (CSRO) regions are formed during annealing. One of them consist mainly of Fe and Co atoms, while others are enriched by Cr with Ni and Mn atoms at their boundaries. It is shown that the formation of short-range order includes several stages, the sequence of which is determined by the value of Cr–Cr, Fe–Co and Ni–Mn interatomic interactions.
Influence of Si on the Structure and Martensitic Transformation in Deformed Ni–Mn–Ga Alloys
Authors: Musabirov I. I. , Gaifullin R. Yu. , Safarov I. M. , Galeyev R. M. , Afonichev D. D. , Kirilyuk K. K. , Koledov V. V. , Mashirov A. V. , Mulyukov R. R.
Published: April 2024

Abstract—The studying the effect of multiaxial isothermal forging on the microstructure and martensitic transformation in the Ni58Mn18Ga24 alloy is presented. Forging was carried out in two stages: stage 1 − forging at 700°C (4 passes, true degree of deformation e ≈ 1.64), stage 2 − forging at 500°C (1 pass, e ≈ 0.24). Forging led to the transformation of the original equiaxed grain structure. As a result of the 1st stage of processing, no new grains are formed. The new recrystallized grains are observed only after the 2nd stage of deformation, the proportion of which is very small. Apparently, the mechanism of fragmentation of the grain structure at the first stage is not triggered due to insufficient defect density at a deformation of 700°C. The characteristic temperatures of martensitic transformation are shifted to the low temperature region. The anharmonic change in the sample length is observed in the region of martensitic transformation for the both treated states. In general, this indicates a low level of defect density and internal stresses in the sample.
The Magnetocaloric Effect in La(Fe,Mn,Si)13Hx Based Composites: Experiment and Theory
Authors: Kamantsev A. P. , Amirov A. A. , Yusupov D. M. , Golovchan A. V. , Kovalev O. E. , Komlev A. S. , Aliev A. M.
Published: April 2024

Abstract—Samples of composites with different porosity and surface roughness based on LaFe11.4Mn0.3Si1.3H1.6 (LFMSH) alloy powders were obtained, their magnetocaloric properties were studied by a direct method in cyclic magnetic fields μ0H = 1.2 T at a frequency of 2 Hz. The maximum value of the adiabatic temperature change in pure LFMSH powder was ΔT = 3 K at Т0 = 287 K in the sample cooling mode; for composite samples, this value turned out to be approximately 2 times lower than in the powder. The effect of Mn and H atoms on the electronic structure and local magnetic characteristics of the initial La(Fe,Si)13 alloy has been studied by the methods of the electron density functional theory. Replacing some of the Fe atoms with Mn reduces the total magnetic moment and slightly lowers the Curie temperature. Hydrogenation, on the contrary, leads to an increase in exchange interactions between Fe atoms located at the vertices of the icosahedron and an increase in the Curie temperature.
Magnetocaloric Effect in Rare-Earth Magnetic Materials
Authors: Pankratov N. Yu. , Tereshina I. S. , Nikitin S. A.
Published: April 2024

Abstract—A study of the magnetocaloric characteristics of rare-earth magnets was carried out. There were studied a systems Gd–H, (Gd,R)Ni–H containing hydrogen (R is a rare earth metal); system RCo2–H with the structure of Laves phases; and systems without hydrogen, such as RTX intermetalic compounds (T = Mn, Fe, Co; X = Si), R2(Fe,T)17 compounds (T = Al), which have a magnetic compensation point and exhibit an alternating magnetocaloric effect (MCE). The MCE was measured by the direct method and calculated indirectly from the field dependences of the magnetization. The main regularities are established and the specific features of the formation of magnetocaloric properties are revealed depending on the composition and structure.
STUDY OF LOW-TEMPERATURE THERMOMECHANICAL BEHAVIOR OF THE Ti-18Zr-15Nb SUPERELASTIC ALLOY UNDER DIFFERENT TEMPERATURE-RATE CONDITIONS
Authors: Derkach M. A. , Sheremetev V. A. , Korotitskiy A. V. , Prokoshkin S. D.
Published: April 2024

The biomedical alloy Ti-18Zr-15Nb (at.%) with shape memory was subjected to a true deformation e = 0.7 in three different modes: in the temperature range from 20°C to 600°C at deformation rate ξ = 0. 1 s-1; at temperatures 250°C and 300°C with strain rates ξ = 0.1, 1 and 10 s-1; deformation at 300°C and strain rate ξ = 0.1 s-1 after annealing at 300°C (τ = 10, 60, 300, 600 and 1200 s). It is established that with increasing temperature the conditional yield strength σ0.2 continuously decreases, at that in the temperature range of deformation temperatures 250°С-300°С the increase of maximum stress σmax is observed. In the temperature range from 200°С to 400°С fluctuations are observed on the flow curves, the amplitude of which increases with increasing temperature. The change σ0.2 and σmax, as well as the presence of oscillations on the strain diagrams are connected with the course of dynamic strain aging accompanied by the release of excess ω-phase particles at temperatures 200°С - 400°С. Increasing the strain rate at temperatures of 250°С - 300°С has a strong effect on the deformation behavior of the alloy due to a significant increase in temperature during the deformation process. Thus, increasing the strain rate up to ξ = 10 s-1 leads to a stepwise decrease in stress, starting from e ≈ 0.3, after which the plastic flow curve acquires a wave-like form with a low frequency of stress fluctuations. The main phase after all modes of thermomechanical tests is the BCC β-phase. At annealing of 300°С and an exposure of more than 300 s weak ω-phase lines are observed, and at deformation after aging significantly broadened ω-phase lines are observed only after prolonged exposure (1200 s).
Structure and Crack Resistance of Maraging Steels under Single Loading
Authors: Simonov Yu. N. , Simonov M. Yu. , Kaletina Yu. V. , Kaletin A. Yu.
Published: April 2024

Abstract—The effect of structural parameters on the strength and crack resistance of maraging steels under single loading has been studied. It has been established that the increase in strength due to dispersion hardening with intermetallic compounds in the studied steels is determined by the titanium content and the presence of cobalt. It was shown that the change in crack resistance under single loading with increasing tempering temperature has a complex character. It has been established that, in contrast to dynamic crack resistance, the minimum level of static crack resistance characteristics of the studied steels corresponds to the maximum strength. Possible reasons for such a change in the characteristics of static and dynamic crack resistance are discussed.
ATOMISTIC SIMULATION OF SELF- DIFFUSION AND DIFFUSION Co ALONG SYMMETRIC TILT GRAIN BOUNDARIES [2¯1 ¯1 0] IN α-Ti
Authors: Urazaliev M. G. , Stupak M. E. , Popov V. V.
Published: April 2024

The structure, point defects, self-diffusion, and diffusion of Co for four energetically preferred grain boundaries (GB) with the tilt axis [21 1 0] in α-Ti are being investigated by computer modeling methods. The structure and energies of the boundaries and the energies of the formation of point defects in GB, were calculated by molecular static modeling. The dependencies of point defect formation energies on the distance from the grain boundary plane are demonstrated. The coefficients of grain boundary self-diffusion are calculated by the method of molecular dynamics. The results of self-diffusion modeling are compared with the available experimental data. The simulation of grain boundary diffusion of the impurity Co in titanium is also performed. It is shown that the structure of GB affects the parameters of grain-boundary diffusion both in the case of self-diffusion and in the case of impurity diffusion, and the coefficients of grain-boundary diffusion may differ by several orders of magnitude depending on the structure.
Thermal Physical Properties of Metals in a Quasi-Two-Phase Model
Authors: Terekhov S. V.
Published: April 2024

Abstract—The applicability of the model of a two-phase locally equilibrium region for calculating the temperature dependences of heat capacities, linear thermal expansion coefficients, and thermal diffusivities of various metals is demonstrated. It is shown that the proposed relations make it possible to describe the increase in the thermal characteristic with increasing temperature and its changes associated with the implementation of the phase transition. The possibility of extrapolating the established dependences to experimentally unexplored areas is indicated. The relative simplicity of the established relationships, a certain universality of the model in describing various solids, and the visibility of the theoretical results obtained give hope for the use of the model in engineering and technical calculations.
Possible Physiological Mechanisms of Leaf Photodamage in Plants Grown under Continuous Lighting
Authors: Shibaeva T. G. , Mamaev A. V. , Titov A. F.
Published: April 2024

Unlike the natural photoperiod that includes the alternation of day and night in the diurnal cycle, continuous (24 h a day) lighting provides uninterrupted supply of light energy required for photosynthesis, permanently promotes photooxidative processes, implies continuous signaling to the photoreceptors, and desynchronizes the internal circadian biorhythms from the external light/dark cycle (circadian asynchrony). The leaves of many plant species grown under constinuous lighting are prone to characteristic and potentially lethal interveinal chlorosis and necrosis. The photodamage of plant leaves exposed to long photoperiods, including daily 24-h illumination was described more than 90 years ago, but the causes of this phenomenon are still not entirely clear. Biological bases underlying this phenomenon are theoretically and practically important, because growing plants under a 24-h photoperiod at a relatively low photon flux density is seemingly an effective way to save resources and increase plant productivity in greenhouses and plant factories with artificial lighting. This review of available literature compiles and evaluates the arguments both supporting and confronting the hypothesis that carbohydrate accumulation, specifically the hyperaccumulation of starch in leaves, is the main cause of photodamage to plants grown under continuous lighting or long photoperiods. The analysis of a large number of studies indicates that the accumulation of carbohydrates is neither the main nor the only cause of leaf injuries in plants grown under a 24-h photoperiod, although the role of this factor in photodamage cannot be ruled out. The appearance and development of photodamage under a 24-h photoperiod is presumably due to several simultaneously acting factors, such as photooxidation, stress-induced senescence, and circadian asynchrony. The contribution of individual factors to photodamage may vary substantially depending on environmental conditions and biological properties of the object (plant species and variety, plant age, and the stage of development).
Plant Cell Cycle: Molecular Events, Regulation by External Factors and Phytohormones
Authors: Nosov A. V. , Fomenkov A. A.
Published: April 2024

This lecture presents classical information and new data on the molecular events of the “basic” (core) cell cycle (CC) of plants. The impact of water deficit, CO2, light, and temperature on CC is briefly examined. Data on the regulation of cell proliferation by auxins, cytokinins, abscisic acid, gibberellins, brassinosteroids, and ethylene are presented. Commonality and peculiarities of the effect of phytohormones on CC in various organs and tissues are discussed.
Improving Salt Stress Tolerance of Triticum aestivum L. with Endophytic Strains of Bacillus subtilis
Authors: Kuramshina Z. M. , Khairullin R. M.
Published: April 2024

The effect of salt stress on Triticum aestivum L. plants inoculated with endophytic strains of B. subtilis was studied. The treatment of Triticum aestivum L. with endophytic bacterial strains of B. subtilis was shown to increase plant resistance to the stress factor. The inoculation reduced the development of oxidative stress and the entry of sodium ions into aboveground plant organs. The antistress effect of endophytic strains of B. subtilis and their ability to reduce the absorption of sodium ions by Triticum aestivum L. plants can be employed to promote plant growth during cultivation of crops on saline lands.
Isolation of CP-PVY-Specific siRNA from PVY-Infected Plants of Solanum tuberosum
Authors: Sutula M. Yu. , Kabataeva Zh. K. , Komekova G. K. , Khosnutdinova T. S. , Zhakmanova E. A.
Published: April 2024

Tools for activating crop resistance to viruses are now becoming part of a comprehensive plant protection
strategy. Artificial resistance to viruses through expression of the viral envelope protein in transgenic
plants is fairly well understood. An urgent issue is the study of small RNAs involved in the protective mechanisms
of RNA interference against viruses. Understanding the role of short interfering RNA (siRNA) in the
regulation and shutdown of genes is important. The proteinase accessory component (HC-Pro), a multifunctional
suppressor protein synthesized by the potato virus Y, is able to neutralize S. tuberosum plant defenses
by trapping siRNA and removing them from the RNA interference process, thereby causing systemic infection
of the host plant. Protein liquid chromatography combined with high performance sequencing can help
recognize the large number of small RNAs resulting from viral RNA degradation and identify 21–23 bp.
siRNA from PVY-infected S. tuberosum plants. The HC-Pro/siRNA nucleoprotein complex was detected in
chromatographic fractions using antibodies against HC-Pro, Southern-blot indicated the presence of small
RNAs in the complex, and analysis of data from deep sequencing of the small RNA population determined a
specificity of 21–23 bp. siRNA to the envelope protein of the PVY virus. The research results can be applied
in the study of intracellular signaling molecules and stimulate new research on antiviral mechanisms to
develop effective strategies for plant protection against viruses.
Characteristics of the complex of polyphenol compounds of Yakutian endemic Dracocephalum jacutense Peschkova using tandem mass spectrometry
Authors: Okhlopkova Zh. M. , Razgonova M. P. , Egorova P. S. , Golokhvast K. S.
Published: April 2024

Dracocephalum jacutense Peschkova is a rare and endangered species of the genus Dracocephalum L. of Lamiaceae family. The species was first described in 1997 and listed in the Red Data Book of Yakutia (2017). Until now, due to the rare occurrence of D. jacutense, almost none of its phytochemical studies have been carried out and there is no information on the content of biologically active compounds (secondary metabolites) of the plant. In this work, using the method of tandem mass spectrometry, a complex of polyphenolic compounds was studied in the inflorescences of the Dracocephalum jacutense, collected in the areas of its first discovery - the Kobyaysky district of the Republic of Sakha (Yakutia). As a result of the analysis, 48 polyphenolic compounds were found in the alcohol extracts of Dracocephalum jacutense inflorescences, among which 17 flavones, 7 flavonols, 3 flavan-3-ols, 12 phenolic acids, 1 lignan, 2 coumarins, 6 anthocyanidins were identified. It should be noted that more than half (30 compounds) of all the identified polyphenols for representatives of the genus Dracocephalum L. were discovered for the first time. The results obtained state the unique composition of polyphenolic compounds in the inflorescences of D. jacutense Peschkova. In order to preserve this sparse local endemic of Eastern Siberia, work has begun on the development of an effective method for its micropropagation in vitro.
Improving Salt Stress Tolerance of Plants with Endophytic Strains of Bacillus subtilis
Authors: Kuramshina Z. M. , Khairullin R. M.
Published: April 2024

Effects of drought on plants of Triticum aestivum L., Brоmopsis inеrmis L., Pisum sativum L., and Zea mays L. inoculated with endophytic strains of Bacillus subtilis bacteria were studied. Presowing treatment of seeds with these bacteria was found to boost plant resistance to water deficit, stimulate their growth, and suppress oxidative stress. Based on the ability of the tested strains to cause antistress effect and activate the antioxidant system, it is concluded that plant treatments with them may favor growing of agricultural crops under drought conditions.
Daily Short-Term Temperature Drops Can Alleviate the Negative Effect of Continuous Lighting on the Photosynthetic Apparatus in Plants
Authors: Ikkonen E. N. , Shibaeva T. G. , Sherudilo E. G. , Titov A. F.
Published: April 2024

Several crops (tomato, eggplant, sweet pepper, and cucumber) were used to examine the impact of continuous (24 h a day) lighting on photosynthetic characteristics of plants grown permanently at 26°C and those exposed daily to short-term (2 h) cooling at 10°C (temperature-drop treatments). The plant response was assessed by indices characterizing the pigment complex and the photosynthetic activity of leaves. Growing plans under continuous light at a constant temperature resulted in leaf photodamage and photoinhibition in all four species, although to varying degrees. The temperature-drop treatments prevented the photodamage of leaves under continuous light in all species and enabled high sustainable levels of photosynthetic activity in tomato, pepper, and cucumber. The results suggest that temperature-drop treatments can be regarded as an agricultural technique that exploits the benefits of continuous lighting while mitigating the negative effects of constant light. However, the effectiveness of this technique would depend on the choice of optimal intensities and durations of the drop treatment since these parameters may vary depending on plant species.
Relationship between Dehydrins and Adaptation of Cajander Larch to Yakutia Cryolithozone Conditions
Authors: Tatarinova T. D. , Perk A. A. , Ponomarev A. G. , Vasileva I. V.
Published: April 2024

Composition and seasonal fluctuations of stress dehydrin proteins of Cajander larch (Larix cajanderi Mayr) growing under extremely cold climatic conditions in Central Yakutia, which are notable for an extraordinary frost resistance, were investigated. Immunoblotting technique made it possible to detect major dehydrins in a molecular mass range of 17–20, 37–42, and 73 kD in the shoots of L. cajanderi for the first time. A high level of polymorphism of dehydrins within a population of L. cajanderi was detected and differences between the examined specimens of trees were mainly revealed in a molecular mass range of 20–37 kD. Within the circannual cycle of larch, the greatest seasonal fluctuations were observed in low-molecular dehydrins, with their content rising at the end of phenological autumn and reaching a steady level in the period of ultralow winter temperatures. The pattern of seasonal fluctuations and wide variety of dehydrins in larch shoots may point to their possible participation in the formation of a unique frost resistance of L. cajanderi upon adaptation of this conifer species to conditions existing in the cryolithozone.
Colleter Formation on the Leaves of Sweet Potato Microclones (Ipomoea batatas L.) under In Vitro Conditions
Authors: Kirakosyan R. N. , Golivanov Ya. Yu. , Trukhachev V. I. , Zaitseva S. M. , Khaliluev M. R. , Baranova E. N. , Kalashnikova E. A.
Published: April 2024

Microclones of in vitro vegetable sweet potato (Ipomoea batatas L.) were received and the formation of colors on their leaves was studied. The studies were carried out on three varieties of sweet potato that differ in the color of their pulp and the peel of the tubers as well as in different ripening periods: Purple, Jewel, and Muskatny. The effect of ½ norm of mineral salts MS medium, 1 norm MS and 1½ norm MS on the morphometric parameters of sweet potato microclones was studied. It was established that the use of ½ norm of mineral salts according to MS medium led to the production of rapidly growing axillary and adventitious shoots and the formation of a powerful root system in the basal part of microcuttings. The formation of secretory outgrowths was found for the first time on the leaves of sweet potato microclones when cultured under in vitro conditions. Neoplasms were referred to colleters and their characteristics were given. The dependence of the colleter formation on the microclone leaves on the cycles of culture is shown.
Comparison of Halophyte and Glycophyte Plants from the Amaranthaceae-Chenopodiaceae Family in Their Ion-Exchange Properties of Polymeric Matrix of Cell Walls
Authors: Meychik N. R. , Nikolaeva Yu. I. , Kushunina M. A.
Published: April 2024

Ion-exchanging properties of the polymeric matrix of the cell walls isolated from leaves were examined. The glycophyte 55-day-old plants of spinach (Spinacia oleracea L., cv. Matador) grown on a nutrient solution containing 0.5, 150, or 250 mM NaCl and the halophyte seepweed (Suaeda altissima (L.) Pall.) of the same age grown at 0.5, 250, or 750 mM NaCl were compared. The ion-exchange capacity of the cell walls was estimated at different pH and ionic strength of a solution. In the structure of the leaf cell walls, three types of cation-exchange groups were found, namely, two types of carboxylic groups (one of them belongs to galacturonic acid residue) and phenolic OH-groups. The quantities of the groups of each type and their ionization constants were determined. The qualitative composition of the ion-exchange groups in the leaf cell walls was found to be uniform in both plant species regardless of their nutrition. However, the quantity of the carboxylic groups of galacturonic acid depended on the ambient salt concentration in a different manner in the glycophyte and halophyte. This change in the composition of functional groups of cell wall polymers was more pronounced in the halophyte and is apparently one of the responses of these plants to salinization. The sharp increase in the NaCl concentration in the medium leads to a decrease in pH in the extracellular water space due to ion-exchange reactions between sodium ions coming from the external medium and protons of the ionized carboxylic groups of the cell walls. The results are discussed in the aspect of participation of the leaf cell walls in plant responses to salinization.
Accumulation of Polyphenols and Naphthoquinones in Morphogenic Cultures of Two Drosera Species
Authors: Morshneva A. V. , Khandy M. T. , Grigorchuk V. P. , Chernoded G. K. , Gorpenchenko T. Yu.
Published: April 2024

A rhizogenic culture of Drosera capensis L. was obtained. An HPLC method with UV and mass-spectrometric detection was applied to analyze the effect of different drying protocols on the yield of individual polyphenols and 1,4-naphthoquinones from the rhizogenic culture of D. capensis L. The results of this analysis were compared with similar data obtained on the previously established morphogenic culture of D. rotundifolia L. that has been maintained for more than 15 years. In the rhizogenic culture of D. capensis L., six compounds were identified for the first time (myricetin-3-O-β-glucopyranoside, rossoliside, 3,3'-di-O-methylellagic acid 4-O-β-D-glycopyranoside, myricetin, 3,3'-di-O-methylellagic acid, and plumbagin).
Variation in Composition of Biologically Active Substances in Flowers and Leaves of Achillea asiatica Serg. Plants Depending on the Region of Habitat
Authors: Kurchenko V. P. , Sushinskaya N. V. , Chudnovskaya E. V. , Tarun E. I. , Shabunya P. S. , Lodygin A. D. , Khrustaleva I. A. , Kupriyanov A. N.
Published: April 2024

Composition of biologically active substances in methanol extracts from the flowers and leaves of Achillea asiatica Serg. plants was examined in representatives of native flora from Siberia and Kazakhstan growing in different regions of Russia (Kemerovo and Khakasiya) and Kazakhstan. Gas chromatography integrated with mass spectrometry and used for analysis of the extracts from flowers and leaves showed considerable differences in the composition and content of mono-, sesqui-, and oxygen-containing terpenoid compounds associated with the region of occurrence. In the examined samples, antioxidant activity in the extracts from flowers of A. asiatica was much greater than in the extracts from leaves. Antioxidant efficiency of the extracts predominantly depends on phenol compounds that do not belong to terpenes. Phytochemical analysis of three samples of A. asiatica taken from different natural habitats showed a pronounced variation in the composition of biologically active substances and their antioxidant activity. This may account for a different medicinal effect of collected A. asiatica grass.
The Influence of a Poplar Leaf Miner on the Radial Growth of the Fodder Plant in Izhevsk City
Authors: Ermolaev I. V. , Zykina N. G.
Published: April 2024

The assessment was conducted regarding the influence of high population density of the Phyllonorycter populifoliella (Treitschke, 1833) leaf miner (Lepidoptera, Gracillariidae) in sustained outbreaks on radial growth of poplar (Populus balsamifera L.). The study was carried out in 2018 in Izhevsk town. A significant negative affect of the miner’s high densities on the host tree’s productivity has been shown. The results of the research allow us to consider Ph. populifoliella an economically significant poplar phyllophages and indicate the need to monitor the state of its populations.
Predictors of Insect Damage to Forest Stands According to Satellite Data on Example of Siberian Silkmoth Dendrolimis Sibiricus Tschetv
Authors: Kovalev A. V. , Tsikalova P. E.
Published: April 2024

Population outbreaks of such species as Dendrolimus sibiricus Tschetv., in Siberian taiga forests begin with areas of several hectares and develop up to hundreds of thousands of hectares, resulting in significant damage to forests. Boundaries of foci change with time depending on external factors, population dynamics, and the state of forage trees. In this regard, it is important to determine the beginning of an outbreak and the affected area in advance as predictors of increasing pest numbers. To assess necessary conditions for an outbreak, a method for assessing state of forest stands is proposed based on remote sensing data. In this regard, it is important to assess risks of outbreaks and to determine in advance their onset times and starting zones. In order to evaluate necessary conditions for an outbreak, a “cascade” of factors is considered: geophysical (solar activity), weather, and the state of forest stands. Each of these factors is characterized by its own area, within the bounds of which any changes in this particular factor affect the insect population.
A Mass Reproduction Outbreak and Estimation of the Spreading Risks for the Small Spruce Bark Beetle in Cedar Pine Forests of the Tomsk Region
Authors: Krivets S. A. , Kerchev I. A. , Bisirova E. M. , Volkova E. S. , Melnik M. A. , Smirnov N. A. , Pats E. N.
Published: April 2024

The results of studying the mass reproduction outbreak of a new invasive pest of the Siberian pine (Pinus s-ibirica Du Tour), the small spruce bark beetle (Ips amitinus (Eichh.)), observed in Siberia for the first time, are presented in this paper. The studies were carried out in the south-eastern part of Western Siberia, within the Tomsk region, in pine forests damaged by an invasive bark beetle. It is shown that the occurrence of the outbreak was provoked by favourable weather conditions of recent decades and the abundance of trees, weakened for various reasons, in the recipient ecosystems of the invasion, among which the outbreak of the Siberian moth in 2016–2018 was of great importance. The small spruce bark beetle population dynamics in new habitats was compared with the native area in Europe, and certain peculiarities were revealed: an increase in the populations’ numbers level, a narrowing of trophic specialisation up to a regional monophagy, a decrease in the role of an interspecific competition due to the displacement of local stem dendrophagous species by the invader, the simultaneous existence of outbreak foci in different development stages and the correlation between their characteristics, the species composition of the forest stands and the weakening factors. An original method for assessing the spreading risk for an outbreak of the small spruce bark beetle breeding in the Tomsk region under the influence of a complex of factors that contribute to an increase in its number has been proposed and implemented at the forestries level.
The Development of Outbreaks of Forest Insects on Different Spatial Scale
Authors: Soukhovolsky V. G. , Ivanova Yu. D. , Kovalev A. V.
Published: April 2024

The work is dedicated to the discussion of the possibilities of describing the dynamics of the forest insect outbreaks development on different spatial scales. The properties of outbreaks were considered on a microspatial scale, where the distribution patterns of individuals across different food sources within the boundaries of a local territory or a stand were analysed, and on a macrospatial scale, where the focus of the analysis were the indicators of the photosynthetic apparatus (leaves or needles) removal over the entire territory of the locus, including primary, secondary and migratory loci. When analysing the microspatial distribution of caterpillars on trees within loci on different stages of gradation, the model of the individuals’ distribution on fodder trees was used as a second order stage transition. The macrospatial processes that occur during the outbreak development include, firstly, the growth of an existing outbreak and the emergence of new connected damaged areas of the forest, and secondly, the emergence of new unconnected secondary foci. To characterise the outbreaks, their fractal dimension D and the characteristics of the “viscous fingers” on the border of the outbreaks were used. Remote sensing data were used to calculate these characteristics. The proposed approaches can be used to predict the development of forest insects outbreak. When constructing and verifying the models, we used data from the Siberian silkworm census and the trees colonisation rate in the outbreak zone, as well as the remote sensing data on the areas and shapes of the foci in the regions of the Krasnoyarsk Territory during an outbreak of the Siberian silk moth Dendrolimus sibiricus Tschetv. in 2015–2019.
Spatio-Temporal Connectivity of the Long-Term Dynamics of the Forest Phyllophagus Insects’ Abundance
Authors: Tarasova O. V. , Krasnoperova P. A.
Published: April 2024

The study was conducted regarding the conjugation of the population dynamics of different forest insects species under different landscape conditions on the territory of the Krasnoturansky pine forest (South of the Krasnoyarsk Territory). The population dynamics conjugation indicates the presence of an ecological mechanism that leads to the coordination of the temporal series of different species’ population dynamics in one habitat or one species in different habitats. This means that using the conjugation indicators of insect dynamics one can indirectly assess the influence of various factors affecting these populations. To assess the spatio-temporal synchronization of the population dynamics of insects in different landscape conditions, the data of the phyllophagous insects counts for the period from 1979 to 2016 were used. According to the phases of dynamics, although the periods of cyclic fluctuations of phyllophages’ populations in different stows are close, the characteristics of the phyllophagous insects number dynamics still differ in both the absolute values and the phases of dynamics, even when the distance between the test sites is relatively small. The “memory” of the system, expressed in the order of the autoregressive model of the population dynamics, is fairly large for the studied complexes of phyllophagous species: the current value of the phyllophagous populations density can be influenced by the population density values from as far as four years before the counts. Such values of “memory” lead to an increase in the populations’ stability margin, and a decrease in the risks of developing insect outbreaks. The determination coefficients close to 1 for the phyllophages dynamics models in the stows of the Krasnoturansky pine forest indicate a weak influence of modifying factors (such as weather) on the population dynamics.
Geoecological Research and Management Principles in the Northern Caucasus’ Mountain Forests
Authors: Bityukov N. A.
Published: April 2024

The article provides an analysis of historical data on the organisation and state of geoecological research in the mountain forests of the North Caucasus and Russia. On the example of regional monitoring of mountain forest ecosystems, the organisation of the multi-purpose nature management within mountain watersheds is demonstrated. Based on the results of the experimental materials obtained from a long-term monitoring at complex forest-hydrological stations, as well as the results of active experiments, recommendations are given for forest management in the mountains. An example of obtaining information by field methods is shown, as well as computer modelling of forestry development in mountainous regions. The scientific principles and ecological bases of farming in the mountainous regions forests are proposed.
Scots Pine Generative Sphere as an Indicator of the Climate-Determined Change in Vital States of the Populations
Authors: Kuznetsova N. F.
Published: April 2024

The problems of transition of Scots pine (Pinus sylvestris L.) from the stable state to an unstable equilibrium and the change of equilibrium population to non-equilibrium as a result of the global warming are discussed. The purpose of the research is to study the state of the southern and central forest-steppe Scots pine populations’ generative sphere on the basis of its seed fullness, assess their vital state in 2020 compared to 2016 – the year of the pine forests’ destabilisation, as well as compared to the state of the steppe populations in the abundant year of 2017. The objects of the study were the central and southern forest-steppe pine populations growing in the ecologically favourable territory of the Voronezh and Belgorod regions. In 2015, their transition from equilibrium to a slightly nonequilibrium systems was recorded. The level of seed fullness in the Stupino and Belgorod populations decreased by 25.6 and 24.6%, respectively, the number of seeds by 37.7 and 22.4%, and the mortality rate of ovules increased by 3.9 and 4.0 times. Comparison of the seed productivity indicators in 2013, 2016 and 2020 showed that at present both plantations can be considered equilibrium systems. The central population has returned to the regional norm (stable equilibrium), the southern one is in a state of unstable equilibrium. The analysis of variance revealed a significant (57.8%) influence of the HTC factor on the generative sphere of the Belgorod population on the basis of full grain. In the last decade, the number of optimal years in the CCR has decreased from 7–8/10 years to 5. It takes 3 optimal years to return pine forests to equilibrium. High rates of the global warming can lead to an imbalance and re-destabilization. A further reduction in the number of optimal years makes it almost impossible for pine forests to return to the regional norm.
The Role of the Stem Pests in Changing the Condition of Coniferous Forests of the North-West of the European Part of Russia
Authors: Selikhovkin A. V. , Popovichev B. G. , Mandel’shtam M. Yu. , Alekseyev A. S.
Published: April 2024

The danger of stem pests’ mass reproduction in the Leningrad Region and the Republic of Karelia is increasing. However, data on their populations’ state in the northwest of the European part of Russia are scarce and very heterogeneous. They include materials from articles and reviews of the sanitary and forest pathology state, which are in turn based on completely different methodological approaches to obtaining information. Generalisation and analysis of data on the increase in the number of stem pests that pose a danger to coniferous forest stands in the north-west of the European part of Russia, taking into account the materials of scientific reports and forest pathology monitoring, is an urgent task of this paper. The greatest danger to spruce stands is the European spruce bark beetle Ips typographus (Linnaeus, 1758), which forms large-scale centres of mass reproduction. The main factors causing the beginning of the formation of breeding centres are weather conditions (hurricane-force winds and the formation of windblows, an increase in the growing season temperature and a lack of precipitation). At the end of the 20th–beginning of the 21st century, the Leningrad R-egion saw an increase in frequency of the stem pests’ mass reproduction outbreaks, especially the European spruce bark beetle. Since the second half of the 20th century, breeding outbreaks have been also observed in the Republic of Karelia. In the Murmansk region, stem pests do not have a noticeable effect on the forest stands condition. These trends correspond to the temperature increase trends in the Leningrad region and Karelia and an insignificant temperature change in the Murmansk region. Additional nutrition for the pine beetles and sawyer beetles in cases of their mass reproduction is an underestimated factor in the forest stands weakening, which significantly affects the growth and condition of surrounding plantations. The appearance of invasive species, such as the small spruce bark beetle Ips amitinus (Eichhoff, 1872) (Curculionidae: Coleoptera), is a potential danger, but at present this species does not show significant activity in pine and spruce forests in the north of the European part of Russia.
Restoration of Vegetation on Fallows in Krasnoyarsk Territory’s Forest Steppes
Authors: Kovaleva N. M. , Sobachkin R. S.
Published: April 2024

The species richness of the long-fallow lands in the Krasnoyarsk Territory’s forest-steppe zone includes 64 species of vascular plants from 50 genera and 19 families. Leading families of cenoflora are Leguminosae (10 species or 16%), Compositae (10 or 16%), Poaceae (9 or 14%) and Rosaceae (7 or 11%). The basis of the long-fallow lands flora were mesophytes (69%) with an insignificant participation of mesoxerophytes (17%) and mesohygrophytes (9%). Among the ecological-coenotic groups, species of meadow-forest forbs and grasses (34%), ruderal (22%) and forest-steppe (14%) species took the largest part. The aboveground phytomass of the grass cover depended on the age of the fallow (p 0.001) and the density of the pine undergrowth (p 0.05). Forb-brome fallows were the most productive among all in the forest-steppe zone (1.14 ± 0.11–2.02 ± 0.25 t ha–1). Forb-gramineous fallows, experiencing a significant edificatory influence of Scots pine (Pinus sylvestris L.) (density of 29600 units ha–1 in terms of large undergrowth), had the lowest aboveground phytomass (0.23 ± 0.06 t ha–1). Fallow plots aged 7–18 years undergo rapid reforestation, with the density of Scots pine varying widely from 0.9 to 29.6 thousand units ha–1 in terms of large undergrowth. It has been established that with an increase in the Scots pine density, the number of species, species diversity, species saturation, as well as the projective grass cover tend to decrease (p 0.001).