bluuebunny/crossref_metadata_2025 huggingface dataset:
INFLUENCE OF THE GAUGE FIELD ON TRANSPORT PHENOMENA IN CONDUCTIVE INHOMOGENEOUS MAGNETIC STRUCTURES
Authors: Lyapilin I. I.
Published: April 2024

The influence of the gauge ("accompanying"), spin-dependent electric field and force induced magnetization dynamics of conducting inhomogeneous magnetic structures, on transport phenomena. It is shown that the transport phenomena, associated with the manifestation of a spin-dependent electric field, lead to the effect of spin Coulomb drag of carriers charge.
Thermal Contact Resistance of the Copper–Copper Pair with Graphene Thermal Interface in Magnetic Fields up to 10 T
Authors: Kolesov K. A. , Mashirov A. V. , Irzhak A. V. , Chichkov M. V. , Safrutina E. F. , Kiselev D. A. , Kuznetsov A. S. , Belova O. V. , Koledov V. V. , Shavrov V. G.
Published: April 2024

Abstract—
The thermal contact resistance of a detachable connection in copper-copper contact pair with a thermal interface from layers of graphene synthesized by the method of a low pressure chemical vapor deposi-tion on the contact surface was studied. Obtaining the value of the thermal contact resistance of a detachable contact pair copper–graphene–copper by the method of transient heat flow, at a temperature of 15–150 K under the influence of an external magnetic field up to 10 T.
Advanced Non-Contact Optical Methods for Magnetocaloric Effect Measuring
Authors: Kamantsev A. P. , Amirov A. A. , Yusupov D. M. , Butvina L. N. , Koshkid’ko Yu. S. , Golovchan A. V. , Valkov V. I. , Aliev A. M. , Koledov V. V. , Shavrov V. G.
Published: April 2024

Abstract—A big problem in magnetic and, in particular, magnetocaloric studies is the accurate measurement of the temperature of materials, especially in high pulsed and alternating magnetic fields. The disadvantages of the used contact temperature sensors (microthermocouples and film thermistors) are: (1) the influence of electromagnetic interference on their readings, proportional to the time derivative of the magnetic field, (2) their relatively long response time due to thermal inertia, (3) the impossibility of accurate measurement temperatures of thin and microstructured samples. The described difficulties can be avoided by using contactless optical methods for measuring the temperature of magnetic materials in high magnetic fields. This review describes advanced non-contact optical methods for measuring the magnetocaloric effect using known materials as an example, and provides a comparative analysis of the main characteristics of these methods, such as: maximum magnetic field, sampling frequency, time constant and spectral range of the detector, error and temperature resolution.
The influence of Ni on the contributions of the superplastic deformation mechanisms of the Al–Zn–Mg–Cr alloys
Authors: Yakovtseva O. A. , Postnikova M. N. , Irzhak A. V. , Rofman O. V. , Mikhaylovskaya A. V.
Published: April 2024

The Ni influence on the superplastic characteristics, the microstructure evolution and the contributions of the superplastic deformation mechanisms for Al-Zn-Mg-Cr-based alloys have been investigated. The alloys contained dispersoids enriched with Cr, Mg and a minor of Zn of a mean size of 140 nm and in addition the Al3Ni phase in the alloy with nickel. Al3Ni phase increased homogeneity and stablity grain structure during elevated annealing temperature and during superplastic deformation at 440°C. The mean grain size decreases from 7.7 to 7.3 µm before the onset of the deformation and from 10 to 8.6 µm after straining of 0.69. The dislocations aggregations near Al3Ni particles were revealed. The microstructure evolution was compared at the testing condition providing a similar value of the strain rate sensitivity coefficient m≈0.6. The grain boundary sliding contribution is twofold larger and the intragranular dislocation slip is three times smaller in the alloy with Al3Ni particles compared to nickel-free alloy. Al3Ni particles leads to more equiaxed finegrain structure and an increase elongation to failure.
Magnetic properties and structure of the Fe63.5Mn10Cu1Nb3Si13.5B9 alloy nanocrystallized under tensile stresses
Authors: Lukshina V. A. , Dmitrieva N. V, , Volkova E. G. , Shishkin D. A.
Published: April 2024

The influence of introduction of 10 at. % Mn for Fe in the classical Finemet (Fe73.5Cu1Nb3Si13.5B9) on its magnetic properties, magnetic anisotropy, and structure is studied after nanocrystallization annealing at 520°C with varying duration from 10 min to 4 h in the presence of tensile stresses (σ = 200 MPa) (SA) and without them (NA). It is established that in the Fe63.5Mn10Cu1Nb3Si13.5B9 alloy (Mn10-alloy), just as in the classical Finemet, SA results in the induction of transverse magnetic anisotropy, yet, the constant of induced magnetic anisotropy is decreased by a factor of 4. The coercivity of the Mn10-alloy grows with increasing annealing time upon both SA and NA, while that of Finemet virtually does not change. Unlike Finemet, in the Mn10-alloy, along with the α-Fe(Si, Mn) solid solution and Fe3Si phase, there form borides already after 10-min treatment. This results in the change in the volume fractions of structure components with a negative magnetostriction, α-Fe(Si, Mn) and Fe3Si, which are responsible for the induction of transverse magnetic anisotropy, and positive magnetostriction, FeB, Fe2B, Fe3B, and hence, most likely, causes decrease in the constant of IMA of the Mn10-alloy. Besides, unlike Finemet, the average grain size in the alloy with Mn increases with the time of annealing, which, together with the formation of borides, increases the coercivity.
Electronic Structure and Magnetic Properties of FeRhSn1 – xZx (Z = Ge, Si, Sb): Ab Initio Study
Authors: Pavlukhina O. O. , Sokolovskiy V. V. , Buchelnikov V. D.
Published: April 2024

Abstract—Magnetic properties and electronic structure of FeRhSn1 – xZx alloys (x = 0, 0.25, 0.5, 0.75, 1) have been investigated by first-principles methods using the VASP software package. It is shown that for all alloys the γ phase is energetically favorable, except for the FeRhSi alloy, for which the β phase is equilibrium. It is shown that the addition of a fourth element to a three-component alloy leads to a change in the position of the valence zone and conduction zone relative to the Fermi level, which makes it possible to obtain new four-component alloys possessing one hundred percent spin polarization. It is shown that FeRhSn1 – xGex (x = 0, 0.25, 0.5, 0.75, 1), FeRhSn1 – xSix (x = 0, 0.25, 0.5, 0.75) and FeRhSn1 – xSbx (x = 0, 0.25) alloys are half-metallic ferromagnets.
Phase Stability of Ni–(Co)–Mn–Z (Z = Ga, In, Sb, Sn) Heusler Alloys
Authors: Erager K. R. , Sokolovskiy V. V. , Buchelnikov V. D. , Gamzatov A. G. , Aliev A. M.
Published: April 2024

Abstract—This work is devoted to the first-principle studies of phase stability and segregation stability of austenitic and martensitic phases of Heusler alloys Ni2 – xCoxMn1 + yZ1 – y (x = 0, 0.25, 0.5 and y = 0, 0.25, 0.5, 0.75; Z = Ga, In, Sb, Sn) with different types of magnetic ordering. Among all the considered compounds, only alloys Ni1.5Co0.5MnGa and Ni2MnGa in cubic and tetragonal structures with ferromagnetic ordering, respectively, as well as Ni2Mn2 in tetragonal structure with staggered and layer-by-layer antiferromagnetic ordering demonstrate stability. For these compositions, the presence of zero convex hull energy and the absence of reactions with positive decomposition energy are shown. The remaining compounds appear to be metastable both due to the presence of stable reactions with negative decomposition energy and decay reactions with positive decomposition energy. The number of decay reactions increases with increasing chemical disorder, i.e., deviation from stoichiometry.
DECOMPOSITION OF THE METASTABLE BETA PHASE IN HIGH-STRENGTH TITANIUM ALLOYS VST5553, Ti–10V–2Fe–3Al, and BETA-21S
Authors: Kalienko M. S. , Zhelnina A. V, , Popov A. A.
Published: April 2024

In this paper the decomposition and evolution of microstructures of the metastable β-phase during aging of Ti10V2Fe3Al, VST5553, and Beta-21S alloys were studied. A comparative study of the evolution of the microstructure and crystal lattice of phases in alloys during aging has been carried out. Features of the nucleation and growth of the secondary α-phase formed during aging were observed using scanning electron microscopy. The concomitant diffusion redistribution of alloying elements between the phases was studied using the method of full-profile X-ray diffraction analysis. It has been established that during aging, the change in the periods of crystal lattices in the studied alloys has a general pattern, which is associated with the common nature of the process of diffusion redistribution of alloying elements between phases. The morphology formed during the decomposition of the secondary α-phase differs between alloys and is determined by the stability of the β-phase after quenching.
Relaxation Annealing Influence on the Magnetic Properties and Magnetic Impedance of Amorphous Co-Based Wires
Authors: Bukreev D. A. , Derevyanko M. S. , Moiseev A. A. , Kurlyandskaya G. V. , Semirov A. V.
Published: April 2024

Abstract—The results of a study of the influence of the 2 hours relaxation annealing at a temperature of 620 K on the magnetoimpedance effect (MI) in amorphous Co66Fe4Nb2.5Si12.5B15 wires are presented. It was found that MI at low ac frequencies after heat treatment increases noticeably, while it changes slightly at high frequencies. Using magneto-impedance tomography, it is shown that this is due to the fact that the changes in magnetic properties caused by heat treatment are not the same in different regions of the wire. Thus, in the surface region with a thickness of about 2.5 μm, the magnetic permeability remains almost unchanged, but in the internal regions it increases significantly after annealing.
Magnetocaloric Effect of Mn2YSn (Y = Sc, Ti, V) Alloys
Authors: Sokolovskiy V. V. , Zagrebin M. A. , Buchelnikov V. D.
Published: April 2024

Abstract—In this paper, the structural, magnetic, and thermodynamic properties of Mn2YSn (Y = Sc, Ti, and V) alloys are considered depending on the applied pressure using the density functional theory and the Monte Carlo method. It is shown that for each compound there are two magnetic states with a low and a high magnetic moment at a smaller and larger unit cell volume, separated by an energy barrier. The barrier value depends on the applied external pressure. The two phases become almost equal in energy at critical pressures of 3.4, –2.9, and –3.25 GPa for Mn2ScSn, Mn2TiSn, and Mn2VSn, respectively. The temperature behavior of the magnetization and magnetocaloric characteristics for the studied phases at various pressures is obtained. Accounting for pressure leads to an understanding of the mechanism of the increase in the magnetocaloric effect in the phase with a high magnetic moment. The greatest effect (ΔSmag ≈ 0.158 J/mol K and ΔTad ≈ 1.1 K) is predicted for Mn2TiSn at a pressure of –2.9 GPa and a change in the magnetic field from 0 to 2 T.
Model of Fusion of Pure Metals
Authors: Chuvil’deev V. N. , Semenycheva A. V.
Published: April 2024

Abstract—There are model for calculating the latent heat of fusion of pure metals, included the contribution of the phonon “analogue of the Casimir force” to the melting of metals. The model makes it possible to explain the mismatch between the experimental value of the latent heat of melting and the theoretically calculated sum of the jump in the configuration and vibrational entropy during the phase transition from solid to liquid. The described approach also makes it possible to estimate the magnitude of the volume change during melting using the values of the crystallogeometric and thermodynamic parameters of the material.
Uniaxial Quadrupole Order in a Magnet With Strong Biquadratic Exchange
Authors: Kokorina E. E. , Medvedev M. V.
Published: April 2024

Abstract—It is shown that in a magnet with a sufficiently strong biquadratic exchange interaction (compared to bilinear exchange) and spin S 1, the temperature transition from a disordered paramagnetic state to the ground ferromagnetic state passes through an intermediate magnetically ordered phase—uniaxial quadrupole ordering. For a magnet with spin S = 3/2, a phase diagram of magnetic states was constructed in the region of large values of the biquadratic exchange and it was studied how the sequence of two phase transitions—“paramagnetic state–quadrupole state” and “quadrupole state–ferromagnetic state”—manifests itself in the temperature behavior of the magnetic heat capacity and the initial magnetic susceptibility.
Effect of Pressure and Gravitational Field on the Distribution of Cu during the Directed Growth of a Single Crystal of the Alloy Al–0.005 wt % Cu
Authors: Esin V. О. , Кrivonosova А. S. , Sattybaev I. Zh. , Fedorova Т. G. , Elokhina L. V.
Published: April 2024

Abstract—Using quantitative X-ray spectral analysis and metallography, the distribution of copper concentration in the α-solid solution of Al and the dislocation density in single crystals of the Al alloy–0.005 wt % Cu, grown from the melt at different values of argon pressure (Ar) and the gravitational field component (gmg) directed along the surface of the crystallization front. A strong inhomogeneity in the copper concentration measured in adjacent areas of the cross-sectional surface of the crystal and its correlation with the inhomogeneity of the distribution of dislocations in single crystals of the alloy, which depends on pressure and the gravitational field component, were discovered. The mechanism of relaxation of the excess free volume of the phase transformation released in the region of the interphase boundary during crystal growth is considered.
Application of In Silico Analysis to Determine Morphogenesis in Plant Tissue Culture
Authors: Malakhova K. V. , Zontikov D. N. , Shcherbakova A. I. , Sergeev R. V.
Published: April 2024

The work proposed and tested a new approach to optimizing biotechnological processes, including the process of microclonal propagation. The proposed method is based on constructing a map of the similarity of the structures of molecules of secondary metabolites of plant extracts and molecules that regulate the processes of plant morphogenesis (primarily phytohormones) with subsequent prediction of the action of the extract. Lichen extract of Cetraria islandica (L.) Ach. (Parmeliaceae)was used as an example, for which the range of secondary metabolites contained is well known. The structural similarity of aliphatic secondary compounds of lichen (protolichesteric and lichesteric acids) with strigolactones (to a greater extent), as well as with gibberellins and brassinosteroids, was revealed. Based on the analysis of the results obtained, a prediction was made about the dose-dependent effect of the lichen extract of C. islandica on growth processes and rhizogenesis of microshootsin vitro. This hypothesis was experimentally tested in experiments with microclonal propagation of higher plants Lonicera caerulea L. and Populus tremula L. As a result of the work carried out, it was established that the addition of extract from C. islandicaat a concentration of 10–50 mg/L in the nutrient medium increased the multiplication rate of L. caerulea (by 31%) and P. tremula (by 8%). The rhizogenic activity of the lichen extract at the same concentrations (10–50 mg/L of medium), similar to the activity of strigolactones and gibberellins, has been experimentally proven. The extract has also been shown to have a positive effect of C. islandica (50 mg/L) on elongation of microshoots of both cultures and hemogenesisof P. tremula.The proposed approach allows for optimizing studies aimed at identifying the effect of various extracts on plant morphogenesis in vitroby preliminary constructing a map of the similarity of secondary metabolites contained in extracts (including according to literature data) and known growth regulators (including phytohormones) with subsequent prediction of the effect of the extract.
Interaction of Soluble and Immobilized Manganese-Stabilizing PsbO Protein with Manganese Ions and Isolated D1/D2/cyt b559 Complex of the PSII Reaction Center
Authors: Khristin Mikhail S. , Smolova Tatiana N.
Published: April 2024

Interaction of water-soluble and immobilized (on BrCN-activated agarose) manganese-stabilizing protein PsbO with Mn2+ and Mn3+ cations and with preparations of D1/D2/cyt b559 reaction center (RC) of photosystem II was studied. By native electrophoresis, the formation of dimeric and aggregated forms of PsbO protein were found in the presence of Mn2+, Mg2+, or Fe2+ ions. The dimerization of PsbO occurred after ultraviolet irradiation of the protein preparation. The presence of protein-bound Mn3+ cations increased the electrostatic interaction of the immobilized PsbO with the RC. This was evidenced to by higher amounts of CaCl2 that were required for dissociation of the PsbORC complex. It was first demonstrated that the protein exhibited superoxide dismutase (SOD) activity after an electrophoresis in PAAG upon incubation of the gel in an Mn2+-containing solution. Tetrazolium-reductase activity was also ascertained in the protein after its electrophoresis in a mixture with preparations of the oxygen-evolving complex (OEC). It is suggested that the protein interaction with Mn ions and superoxide radicals, as well as short-term UV irradiation, reduces tyrosine and a disulfide bond in the PsbO protein. This yields tyrosil radical and SH-groups participating in redox reactions with ETC components. The interactions of PsbO with Mn cations and UV light, taking place in the chloroplast thylakoids, may regulate the protein binding to RC, modify structural organization of the protein, and promote its participation in alternative pathways of electron transport under the influence of stress factors. The hypothetical scheme of interaction of the immobilized PsbO protein with Mn ions and RC is discussed.
Photosynthesis: Theory and Experiment
Authors: Zvalinsky V. I.
Published: April 2024

The approach we developed earlier to describe the chains of conjugate enzymatic reactions of the photosynthesis process for the first time made it possible to propose a strict mathematical model of non-rectangular hyperbola, which describes the dependence of the speed of photosynthesis on the intensity of light (I), the concentration of CO2 and the interaction of these two factors. The fundamental parameters of this model are light (IK) and carbon dioxide (CK) substrate constants, as well as hyperbola curvature (), conjugation parameters (rIP and rCP) and maximum photosynthesis rate (Pm). Special straightening coordinates are proposed, in which the entire hyperbole family has the form of a straight line. The main parameters can only be found when constructing experimental data in straightening coordinates. The proposed non-rectangular hyperbola model is applicable both for describing the process of photosynthesis in seaweed and higher plants, and for absorbing vitamin B12 by algae, and the dependence of the rate of food consumption by zooplankton and fish.
Polyesters of 14-Hydroxylated Taxoids Found for the First Time in Taxus canadensis Intact Plants
Authors: Kochkin D. V. , Demidova E. V. , Globa E. B. , Glagoleva E. S. , Galishev B. A. , Nosov A. M.
Published: April 2024

Taxane diterpenoids (taxoids) are found only in representatives of the Taxaceae family (different yew species); however, the unique structure and therapeutic properties of taxoids, which are in demand in medicine, have made these compounds one of the most studied secondary metabolites of higher plants. In this work, for the first time, a detailed study is performed into the structural diversity of polyesters of 14-hydroxylated taxoids in Taxus canadensis a yew species, for intact plants of which nonpolar 14-hydroxylated taxoids have not been previously described. At the first stage of the work, it was shown using chromato-mass spectrometry that polyesters of 14-hydroxylated taxoids (yunnanxan, taxuyunnanin C, sinenxan B, sinenxan C) are the dominant diterpenoid secondary metabolites in T. canadensis callus cell culture. Based on these results, as well as the similarity of the metabolism of cultivated in vitro plant cells and root cells in planta, it was suggested that polyesters of 14-hydroxylated taxoids will preferentially accumulate in the roots in intact T. canadensis plants. The validity of this hypothesis was confirmed using liquid chromatography-mass spectrometry and nuclear magnetic resonance spectroscopy (NMR). According to chromato-mass-spectrometric screening in T. canadensis needles, polyesters of 14-hydroxylated taxoids are actually found only in trace amounts, while they are one of the major (quantitatively) diterpenoids in the roots. One of the main 14-hydroxylated taxoids of T. canadensis roots, yunnanxan, was isolated preparatively and uniquely identified using NMR spectroscopy and high-resolution mass spectrometry. This work is the first report on the presence of polyesters of 14-hydroxylated taxoids in intact Canadian yew plants.
Involvement of Nitric Oxide in Regulation of Plant Development and Resistance to Moisture Deficiency
Authors: Allagulova Ch. R. , Yuldashev R. A. , Avalbaev A. M.
Published: April 2024

Nitric oxide is a universal signaling molecule involved in the modulation of metabolic activity during the normal growth and development of plants, and in the formation of their resistance to environmental stressors. The review presents key information that reflects the current state of the problem of the regulatory role of NO in plants. Brief information on physicochemical properties of NO, methods of its research, ways of biosynthesis and functional activity at different stages of plant development (germination, vegetative growth, flowering, root formation, symbiosis, mineral nutrition) are given.In addition, the appearance of the protective effects of NO under conditions of moisture deficiency is described, since disturbance of the water regime and dehydration of plants is observed under the influence of various abiotic stress factors, including drought, salinity, hypo- and hyperthermia. Particular attention is paid to the molecular mechanisms of NO-dependent signaling, which are implemented in plants at the genomic, proteomic and post-proteomic levels during multiple nitration reactions. Understanding the mechanisms of regulatory action of NO in normal and under stress is of important theoretical and applied importance in connection with the need for a fundamental justification of the possibility of practical use of NO in order to increase the stability and productivity of cultivated plants.
In Vitro Regeneration of Fern via Green Globular Bodies
Authors: Shelikhan L. A.
Published: April 2024

Green globular bodies (GGB) are special shootspropagules formed during the in vitro cultivation of plant tissues. Due to the high propagation rate, GGB are considered cost-effective for in vitro regeneration of important food and ornamental ferns. In addition, propagation using these meristem structuresoffer the challenge for the conservation of rare or endangered ferns. GGB tissues can be used for long-term storage by in vitro cell culture cryopreservation. The review presents the current state of research on the in vitro reproduction of ferns via GGB regeneration. The concept of GGB and the stages of their development are discussed. Conditions for GGB in vitro introduction into culture, their initiation, proliferation, differentiation, rooting and acclimatization of sporophytes are discussed. Particular attention is paid to the effect of the composition of nutrient media on the GGB multiplication efficiency.
Effect of Photoperiod Duration on Efficiency of Low-Temperature Hardening of Arabidopsis thaliana Heynh. (L.)
Authors: Popov Valery N. , Deryabin Alexander N.
Published: April 2024

The effect of photoperiod duration on efficiency of low-temperature hardening was investigated in Arabidopsis thaliana (L.) Heynh. plants, ecotype Col-0. Six-week-old plants were exposed to cold acclimation at a temperature of 2С during 1‒5 days at photoperiods of 0, 8, and 16 h (illuminance of 200 mol/(m2 s)). According to survival data and leakage of electrolytes after test freezing (6C, 24 h), the plants exposed to cold acclimation in the dark did not show frost resistance. The plants hardened in the light (irrespective of the length of photoperiod) considerably improved their frost resistance by the end of the cold-acclimation period. Net photosynthesis/dark respiration ratio in these plants was almost two times greater than in control material (without hardening). The plants exposed to a 16-h-long photoperiod surpassed the type of treatment with 8-h-long illumination both in the highest levels of accumulation of sugars (by almost 40%) and in the rate of reaching these levels in daily dynamics of hardening. It was shown that MDA content transiently rose during the first 24 h of hardening in the light and did not change in the dark, which may point to a signal role of lipid peroxidation products upon cold acclimation. It was discovered that the photoperiod duration affected the formation rate of frost resistance in A. thaliana plants. A more prolonged operation of A. thalianas photosynthetic apparatus at 16-h-long photoperiod considerably accelerated the accumulation of sugars upon cold acclimation and, therefore, hastened development of frost resistance as compared with an 8-h-long photoperiod. It was concluded that rapid formation of frost resistance in A. thaliana requires a combination of low above-zero temperature and 16-h-long photoperiod.
Characteristics of a New Halotolerant Arctic Strain of Carotenogenic Microalga Halochlorella rubescens NAMSU SBB-20
Authors: Zaitseva A. A. , Bakhareva D. A. , Zaitsev P. A. , Lobakova E. S.
Published: April 2024

Green microalgae capable of accumulating secondary carotenoids are the most important objects of biotechnology, and the search for new strains with unique properties, in particular, those adapted to growth at low temperatures and high salinity in the environment, is an urgent task. The NAMSU SBB-20 microalga strain was isolated from an algal-bacterial biofilm found on the coast of the White Sea in the littoral zone of the Solovetsky Archipelago. Identification of the strain showed its belonging to the species Halochlorella rubescens P.J.L.Dangeard. The species H. rubescens was first described for the White Sea. Under conditions of high light intensity, ultrastructural changes in cells are shown, among which destruction of the photosynthetic apparatus and the formation of cytoplasmic and chloroplast lipid inclusions are noted. It was shown that the culture of the NAMSU SBB-20 strain is capable of acquiring an orange color under unfavorable growth conditions. An assessment was made of the effect of the composition of the medium and the intensity of illumination on the pigment composition of the algae. The highest absolute values of the accumulation of carotenoids were noted during cultivation in light with an intensity of 150 mol PAR quanta/m2/s on BG-11 media containing no source of phosphorus (15.66 0.18 mg/L) or nitrogen (15.95 0.56 mg/L). The described strain has a biotechnological potential due to the initial halotolerance and the accumulation of high values of secondary carotenoids in the biomass.
Secondary metabolism in Taxus spp. plant cell culture in vitro
Authors: Tomilova S. V. , Globa E. B. , Demidova E. V. , Nosov A. M.
Published: April 2024

The genus Taxus (yew) is a source of a number of high-value medicinal substances, particularly, paclitaxel (taxol)a complex diterpenoid compound with a powerful antitumor action (trade name of Taxol). Paclitaxel is one of the most efficient drugs in chemotherapy owing to its specific ability to suppress proliferation of tumor cells via stabilization of their microtubules. The world-wide demand for taxol is 8001000 kg a year and these figures annually rise by 20%. The growing need for paclitaxel and its derivatives and the shortage of plant resources necessary for their production made compounds of the taxane group one of the most important objects for development of biotechnological methods of their production. Out of all the possible ways of taxol production (isolation from wild or plantation trees, total chemical synthesis or semisynthesis, use of yew cell cultures, techniques of metabolic engineering, and use of yew endophytic fungi), the most promising is industrial cultivation of Taxus spp. cell cultures. This review examines the papers dealing with investigation of secondary metabolism in dedifferentiated cells in vitro of various yew species and feasibility of industrial use of cell cultures for production of taxoids. We revealed a number of specificity of Taxus spp. Cell cultures: (1) from a cytophysiological aspectdifficult initiation of cell cultures, their low growth characteristics, specific media and culturing conditions; (2) from a phytochemical aspectdistinction from intact plants in qualitative composition and content of secondary metabolites accounted for by specificity of cell culture as a biological system; predominant formation of С14-hydroxylated rather than of С13-hydroxylated taxoids; an opportunity for elevation of the content of taxoidsincluding commercially valuable ones (paclitaxel and baccatin III) with the aid of different tools (elicitation, stress exposures, two-phase cultivation and some others); (3) from a biotechnological aspectpossibility of industrial cultivation of yew cell cultures; existence of several successful industries (Germany and the Republic of Korea).
The Role of SnRK1 Kinase in the Response of the Photosynthetic Machinery to Salinity Stress
Authors: Murtuzova Alexandra V. , Tyutereva Elena V. , Voitsekhovskaja Olga V.
Published: April 2024

In plants, SnRK1 (Sucrose non-fermenting-Related protein Kinase 1) is one of the major activators of catabolic processes, including autophagy, during stress responses. SnRK1 generally acts as a sensor of the energy status of the cell. Photosynthesis is by far the largest energy-supplying process in green plant cells exposed to light; thus, SnRK1 might participate in its regulation. In leaves of Arabidopsis lines with different levels of the catalytic subunit of SnRK1, KIN10, quantum yields of photosystems and of non-photochemical quenching, formation of the transthylakoid proton motive force, and contents of ATP in seedlings were compared under optimal conditions and under salinity stress. We detected specific changes in the photochemical activity of the chloroplasts that were assigned to constant activation of SnRK1 in two lines with constitutive overexpression of KIN10, both under control conditions and under salinity stress. Furthermore, the inhibition of the SnRK1 activity by means of RNA interference in Arabidopsis led to a lack of response to salinity at the level of chloroplast photochemistry.
Cultivation of Arabidopsis thaliana in a Laboratory Environment
Authors: Fridman V. A. , Fadeev V. S. , Tyurin A. A. , Demyanchuk I. S. , Goldenkova-Pavlova I. V.
Published: April 2024

Arabidopsis thaliana (L.) Heynh. is one of the major model organisms used in different areas of science: plant physiology and biochemistry, developmental biology, genetic engineering, genome editing, etc. These model plants possess the following advantages: short life cycle, simple cultivation, sequenced and rather well annotated genome, and numerous available reports concerning transcriptome, proteome, metabolic pathways, and mutations. The technique of A. thaliana cultivation under laboratory conditions is an important aspect of investigations dealing with this plant as a model. Choice of the growing mode depends on the goal of investigation as well as on quantity and type of required biomaterial. The aim of this work is to review the techniques of A. thaliana cultivation and their applicability to different tasks.
Lighting intensity affects the fatty acid composition of total lipids of basil leaves and roots (Ocimum basilicum L.)
Authors: Ivanova T. V. , Voronkov A. S.
Published: April 2024

The vegetative organs of common basil (Ocimum basilicum L.) grown in water culture at different levels of illumination (50, 100, and 150 μmol PAR quanta/(m2 s)) for 21 days were studied. In the work, the Purple Velvet basil variety, which is popular in agriculture and has intensely colored leaves was used. The biomass, water content, and composition of fatty acids (FA) of total lipids in the leaves and roots of plants and the content of malondialdehyde and chlorophylls (a, b) in the aerial parts of plants were determined. The sensitivity of the FA composition and morphophysiological parameters (biomass and chlorophyll content in leaves) of O. basilicum plants to the intensity of illumination was shown. The greatest effect was caused by the illumination intensity mode of 150 μmol/(m2 s). Species composition of O. basilicum FA under all lighting conditions was wider in root lipids; however, more pronounced changes in the qualitative composition of Fas were observed in leaves. Photodependent regulation of FA component composition of O. basilicum manifested itself in an increase in the proportion of unsaturated FAs, especially polyene ones, which led to an increase in the unsaturation index (UI) of esterified lipid FAs. The highest UI values were obtained with illumination of 150 μmol/(m2 s). At the same time, with an increase in the illumination intensity, a significant increase in the activity of ω-3 and ω-9-desaturases occurred, which indicates in favor of their lightdependent activation. Thus, increasing the intensity of lighting to certain values directly proportionally affects the physiological parameters of O. basilicum. The maximum indicators of productive growth and the implementation of adaptive mechanisms of green and underground parts of basil plants correspond to illumination of 150 μmol/(m2 s).
Rare Plant of Central Yakutia Polygala sibirica L.: Phytochemical Profile and In Vitro Morphogenic Culture
Authors: Okhlopkova Zh. M. , Razgonova M. P. , Kucharova E. V. , Egorova P. S. , Golokhvast K. S.
Published: April 2024

Polygala sibirica L. is a rare and endangered plant species that is listed in the Red Book of the Republic of Sakha (Yakutia) under category “3 c” as a species with a narrow ecological limitation to limestone rock outcrops. For the first time, the phytochemical profile of the above-ground phytomass of P. sibirica growing in Central Yakutia was studied, and in vitro culture induction was performed. Using HPLC-MS/MS and tandem mass spectrometry methods, 74 compounds were allegedly identified in methanol extracts of the above-ground phytomass of the P. sibirica, of which 40 compounds were identified for the first time within the genus Polygala L., including 22 polyphenolic compounds: flavones (isoformononetin, syringetin, apigenin 7-O-glucoside, etc.), flavonols (herbacetin, myricetin, etc.), flavan-3-ols (afselequin, epicatechin, etc.), flavanones (hesperitin, eriocitrin), phenolic acid, and anthocyanins. A primary callus culture of P. sibirica was based on leaf explants of intact plants with the study of the dynamics of growth of raw and dried cell biomass. On the basis of callus tissue, indirect morphogenesis with abundant shoot formation is initiated. Thus, the basis has been laid for the subsequent propagation of the rare plant P. sibirica for the purpose of reintroduction in the conditions of the Yakut Botanical Garden.
Influence of Presowing Treatment of Seeds with Salicylic Acid on Growth and Photosynthetic Apparatus of Barley with Different Zinc Contents in Substrate
Authors: Ignatenko Anna A. , Batova Yulia V. , Kholoptseva Ekaterina S. , Kaznina Natalia M.
Published: April 2024

Under the conditions of a growing experiment, the authors studied the effect of presowing treatment of seeds with salicylic acid (SA) on the growth parameters and photosynthetic apparatus (PSA) of barley plants (Hordeum vulgare L.), which are in optimal conditions of mineral nutrition or with a lack of zinc in the root environment. It has been shown that zinc deficiency does not adversely affect PSA but causes inhibition of plant growth. Presowing treatment of seeds with SA (10 M) had a stimulating effect on the intensity of photosynthesis and stomatal conductance, which ensured successful plant growth under conditions of zinc deficiency. At the same time, in plants grown from seeds treated with SA, the content of zinc in the roots and shoots was higher than in plants whose seeds were not treated. Based on the obtained results, a conclusion was made on the possibility and prospects of using presowing seed treatment with SA for growing barley plants under conditions of zinc deficiency in the root environment.
Relations of Phenolic Compounds, Tannins, Lignin, Nitrogen and Carbon in Plants of the Empetro-Piceetum Forests of the Kola Peninsula
Authors: Artemkina N. A.
Published: April 2024

The study presents an analysis of aging (falling) organs (leaves/needles) of the following plants: Siberian spruce (Picea abies ssp. obovata (Ledeb.) Domin), downy birch (Betula pubescens Ehrh), common cowberry (Vaccinium vitis-idaea L.), crowberry hermaphroditic (Empetrum hermaphroditum Hager.), blueberry (Vaccinium myrtillus L.), Schreber’s pleurium (Pleurozium schreberi (Brid.) Mitt.), polytrichum (Polytrichum spp.), dwarf cornel (Chamaepericlymenum suecicum (L.) Aschers. Graebn. (Cornus suecica L.)), wavy hair-grass (Deschampsia flexuosa (L.) Trin.). A significant variation in the chemical composition (the content of lignin, phenolic compounds, tannins, nitrogen and carbon, as well as the stoichiometric ratios “C/N”, “lignin/N”, “lignin/cellulose”) was found among plants of the northern taiga forests at the interspecific level. The influx of secondary metabolites with litter depends on the plant communities’ species composition and the contribution of various plant species to the vegetation cover’s composition. At the intraspecific level (for Siberian spruce growing in different landscape positions within empetro-piceetum forests (in automorphic, transit and accumulative landscapes)) an increase in the content of soluble tannins (p 0.05) in spruce needles from the automorphic positions of landscape was determined. Also have been studied some interrelations between secondary metabolites, nitrogen and carbon in the composition of aging photosynthetic organs of dominant plant species in northern taiga empetro-piceetum forests.
Modern Aspects of Studying The Phyllophagous Insects Role in Forest Communities
Authors: Utkina I. A. , Rubtsov V. V.
Published: April 2024

This paper presents a review of publications on the relationship between the phyllophagous insects and the forest communities in the current ecological situation, when ongoing climate changes, manifested primarily in an increase in the air temperature and a change in the precipitation amount and distribution, affect all processes in natural communities. Changes in the ranges of many plants and animals species are observed – moving up northwards and up in altitude. The spring phenophases come earlier, the autumn ones come later, the vegetation period lengthens and the terrestrial plants biomass increases. Such phenomena, together with changes in climatic parameters, affect herbivorous animals, which include insects with various food specialisations and different life cycles. As before, despite the growing number of observations in different parts of the Earth, there remains a lot of uncertainty about how individual plant and insect species and their functional groups function under the changing external conditions. It is emphasized that it is necessary to continue long-term studies in specific natural conditions in order to more accurately determine the reaction of the interactions’ participants to local climate changes and understand what the forestry strategy should be in the current and the predicted future situation.
Changes in a Parcel Structure of Liana-Broadleaved Forests in Primorsky Region Over 20 Years
Authors: Moskalyuk T. A.
Published: April 2024

The study of the parcel structure dynamics of the Primorsky region’s forests is necessary to identify the natural restoration patterns of a formation unique to the region - primary coniferous-broad-leaved forests. As a result of economic activity, these forests, saturated with relic elements, were replaced by secondary ones in most of the affected area. The studies were carried out in the catchment area of the Komarovka river (Southern Primorye, Ussuri region). The article presents the results of the parcel structure study in the broad-leaved-linden hazel with liana vegetation of the herb forest type, which is representative for the region and is also the most complex as far the derivative forests formation is concerned. The classical research method was used: a detailed description and mapping on a scale of 1 : 100 of all phytocoenosis levels was performed on a permanent trial plot (PTP), followed by a pairwise maps comparison and the parcels allocation. An analysis of the phytocoenosis transformation over 20 years of restorative succession has shown that the main silvicultural and inventory characteristics of the stand have changed insignificantly. In the forest stand’s composition, an almost complete dropping out of aspen and linden has occurred, the latter being one of the main species of the local ecosystems. At the same time, the positions of the underbrush and the tree species, characteristic of primary coniferous-deciduous forests, have both strengthened. Changes in the parcel structure indicate the successful restoration of the primary forest type: two secondary complementary (small) parcels disappeared in the phytocoenosis, one more has joined the six conditionally-indigenous ones; there also was a natural enlargement of conditionally indigenous parcels and the alignment of their boundaries. The high indicator role of the grass layer was properly reflected in the study.
Feeding Area and Growth of Trees in the Middle-Aged Pine Plantations
Authors: Rogozin M. V.
Published: April 2024

Pine plantations of class 1B were studied, with a density of 0,95 on an area of 0,64 ha, created in a cleared area following the 1.82 × 1.10 m plan. Alive and dead trees and their feeding areas were plotted on the plan in the ArcMap-ArcView programme. The territory was divided into 9 sections, with a density of 76–122% of the average for the plantation. The feeding area the trees had at the age of 30 years affected the trunk diameter at 55 years in sparse areas of the stand on average by 13.3%, and in denser areas by 5.0%. That confirmed the hypothesis that the influence of the tree feeding area on the trunk diameter can also be weak in the middle-aged stands, and the magnitude of its influence depends on the density of the stand. Tree mortality by the age of 55 correlated with the frequency in feeding area classes (r = 0.96 ± 0.03), thus the feeding area being less than the average value increased the probability of a tree falling off by the age of 55 by only 7%. It has been suggested that the decrease in the affect the feeding area has at high density is due to the increased cooperation of trees. With simulated thinning of the stands, with an increase in the feeding area of the remaining trees by 2 times, a corresponding increase in diameter was obtained only in 11% of the trees. The remaining 89% of the trees did not take advantage of the larger feeding area and did not increase in size, despite 25 years of development with a sparser standing. This indicates that in plantations of the second age class, an increase in the feeding area no longer leads to an improvement in their development in the vast majority of cases. Therefore, the density should be reduced at a much earlier age, for example, at 10–15 years.
Comparative Assessment of the Functional Efficiency of Arboriflora Species Composition in Urban Green Spaces
Authors: Shikhova N. S.
Published: April 2024

The article discusses the results of a comprehensive analysis of the ecological state and environment-stabilizing functions of the species composition of arboriflora in the urban planting structure. It’s based on a large amount of factual material obtained during the course of a long-term monitoring of Vladivostok’s urban greenery. A methodological substantiation has been developed for a comprehensive qualitative-quantitative assessment of species using the applied qualimetry techniques. An integral indicator, named the coefficient of the functional efficiency of the species (JFEC) was proposed as the main evaluation unit. It is a relative-quantitative magnitude of plants quality that characterises their functional efficiency and significance in urban ecosystems: prevalence in greenery planting, vitality, the ability for accumulation of the priority pollutant metals in the urban environment, their concentration relative to the local ecological background; the capability for accumulating metals from the soil. Comparative analysis of the functional efficiency of 80 species of trees and shrubs forming the urban greenery of Vladivostok on the basis of the proposed coefficient was carried out. Among the compared sample of plants, the JFEC decreases from 3.70 (Crataegus pinnatifida) to 1.13 (Malus mandshurica). This values measure up to 74 and 23% of the quality standard (QS), which corresponds to the ideal plant species. The groups of species of different functional significance in the urban green spaces structure have been identified. The best efficiency in creating the comfortable environmental conditions in the city was demonstrated by species widespread in landscaping: Fraxinus mandshurica, Ulmus japonica, Betula platyphylla, Physocarpus opulifolia et al. They are characterized by the maximum participation in the formation of the urban greenery structure and a high ability to absorb the main pollutants of the urban environment. The JFEC of these species is within 3.26–2.61, which corresponds to 65–52% of the QS. In conclusion, author makes a suggestion on a rational use of species for the formation of a comfortable urban environment and introduction of the results into the practice of managing the urban green fund.
Vitality Structure of the Middle-Aged Northern Taiga Pine Forest Stands
Authors: Stavrova N. I. , Gorshkov V. V. , Katyutin P. N.
Published: April 2024

On the example of the northern taiga pine (Pinus sylvestris L.) forests of the western Kola peninsula (67°30′–68°10′ N, 33°57′–34°21′ W) the vitality structure of the middle-aged forest stands was studied in the communities within the lichen, lichen-green moss and green moss groups of forest types (12 permanent sample plots). It has been established that the studied forest stands are characterized by a numerical predominance of moderately and severely weakened trees (total share of 55–70%), and of moderately weakened and healthy trees in terms of trunk volume (total share of 50–75%). The significant factors found to contribute into the formation of the middle-aged pine forest stands’ vitality structure are their density, the sum of the basal areas and the forest type. The density of the forest stand is the main contributor to the nature of the trees’ vitality differentiation. Three main types of pine vitality spectra were identified, differing in the value of the stand vitality index.