The discovery of bidirectional microRNA transfer between two organisms during plant-microbe interactions and the ability of some fungal pathogens to absorb double-stranded RNA (dsRNA) or short interfering RNA (siRNA) from the environment provided an impetus for exploiting this mechanism in plant defense against pathogens. In this study, we investigated the role of conserved wheat microRNAs (miRNAs), miRNA408 and miRNA159, in inducing plant defense responses and suppressing the virulence of the phytopathogenic ascomycete fungus Parastagonospora nodorum, mediated by necrotrophic effectors (NEs) encoded by SnTox genes regulated by fungal transcription factors (TFs). The foliar spraying with in vitro synthesized siRNA408 and siRNA159 duplexes before inoculation with SnTox3-producing P. nodorum isolate increased wheat plant resistance to the SnB isolate and suppressed the pathogen growth and development. Most likely, silencing of the miRNA408 target genes TaCAT-2A, TaCAT-2B, and TaCLP1, and the miRNA159 target gene TaMYB65, led to the induction of a defense response of wheat plants against P. nodorum. This defense response was characterized by a decrease in the catalase activity, accumulation of hydrogen peroxide, activation of the expression of salicylic acid signaling pathway genes (TaWRKY13, TaPR1), and suppression of the expression of ethylene signaling pathway genes (TaEIN3, TaPR3). We demonstrated for the first time the ability of siRNA159 and siRNA408 to penetrate the mycelium of the pathogen P. nodorum and be involved in the cross-kingdom regulation of fungal genes to suppress the expression of some genes of NE (SnToxA, SnTox3) and fungal TFs (SnStuA). We predicted potential targets for wheat miRNA408 and miRNA159 in the P. nodorum transcriptome, making spray-induced gene silencing (SIGS) promising for use against this pathogen. These results provide valuable insights for studying the cross-kingdom transfer of plant miRNAs.

The need to adapt the global industry and economy to increasingly severe climate change, as well as the constant growth of energy consumption, contribute to the development of carbon-free power generation technologies. Energy sources with near-zero emissions include renewable and nuclear energy, but due to the small amount of high-potential renewable energy resources near large electricity consumers, nuclear power plants play a key role in the potential transition to a carbon-neutral economy. They, in turn, have a number of disadvantages, including relatively low energy efficiency, maneuverability, and high specific capital investments. A partial solution to these problems may be the combined use of fossil and nuclear fuel at nuclear power plants. This paper is devoted to the thermodynamic analysis of the use of fossil fuel at NPPs in an external superheater with subsequent operation of part of the steam in a high-temperature turbine. A circuit solution is proposed that provides an extended range of change in the load of the power unit. According to the results of thermodynamic analysis, it was found that external superheating of a part of steam from the steam generator allows an increase in the generated capacity and efficiency of the nuclear power unit: the maximum increase in electric capacity is 338, 382 and 426 MW, and the net electric efficiency is 0.73, 1.08 and 1.43 % for steam superheat temperatures of 560, 600 and 640 degrees C, respectively. The hybrid nuclear-hydrocarbon power unit operating according to the proposed scheme has a smaller amount of primary equipment and has a wider range of load changes compared to free-standing NPPs and steam turbine TPPs: it is 102.3-132.7 %, 103-136.9 % and 103.6-141.2 % relative to the base scheme of NPP for steam superheat temperatures of 560, 600 and 640 degrees C, respectively. The results of the development of the design of an external superheater with dimensions of 38.4x5.4x11.2 m are also presented. It was found that an increase in combustion temperature from 900 to 1400 degrees C leads to a reduction in the heat exchange area by 29.9 %: from 53,100 to 37200 m2 and the average temperature of the furnace surfaces at a combustion temperature of 1050 degrees C is 563 degrees C. It was revealed that the air heater is the most metal-intensive element of the boiler due to the need for deep utilization of the heat of exhaust gases at a low temperature head.

Emissions reduction and energy saving at thermal power plants are crucial for energy development. This paper presents the results of thermodynamic analysis and optimization of thermal circuits of combined-cycle power plants incorporating an organic Rankine cycle and supplementary burners. It is established that at a power unit with GTE-170, the transition from a binary cycle with a double-circuit waste heat boiler to a trinary one leads to an increase in net efficiency by 0.79%. It is established that in the trinary cycle, fuel afterburning in the exhaust-gas environment leads to an increase in the net capacity of the power plant: the increase is up to 4.1% with an increase in the degree of afterburning by 0.1 at a steam temperature of 515 °C. It was revealed that the introduction of intermediate superheat provides an increase in the efficiency of the binary cycle by an average of 0.2–3%, and of the trinary cycle by 2–4%, with a change in the degree of afterburning from 0 to 0.5 at an initial steam temperature of 515 °C. The use of supplementary combustion and the organic Rankine cycle make it possible to reduce carbon dioxide emissions in combined-cycle power plants. Compared to a single-pressure combined cycle, the ORC-integrated configuration reduces specific CO2 emissions by more than 7.5%, while supplementary fuel combustion with an increased steam inlet temperature results in a reduction of up to 10%.

Abscisic acid (ABA) is not only important for plant responses to abiotic stresses, but also plays a key and multifaceted role in plant immunity. In this work, we analyzed the role of ABA in the development of resistance/susceptibility in the wheat (Triticum aestivum L.)–Stagonospora nodorum Berk. pathosystem, which includes the recognition of the necrotic effectors (NEs) of a pathogen by the corresponding wheat susceptibility genes. We studied the interaction of the S. nodorum SnB isolate, which produces two NEs, SnToxA and SnTox3, with three wheat genotypes having different combinations of the corresponding host susceptibility genes (Tsn1 and Snn3-B1). The results of this work on the gene expression and redox status of resistant and sensitive wheat genotypes treated with ABA show that ABA signaling is directed at inducing the resistance of wheat plants to S. nodorum SnB isolate through the activation of the early post-invasive defense genes TaERD15 and TaABI5. The induction of the expression of these genes leads to reactive oxygen species (ROS) accumulation during the early stage of infection, with the subsequent limitation of the pathogen’s growth. In the presence of a compatible interaction of SnTox3–Snn3-B1, ABA signaling is suppressed. On the contrary, in the presence of a compatible interaction of SnToxA–Tsn1, ABA signaling is activated, but the activity of the early post-invasive defense genes TaERD15 and TaABI5 is inhibited, and the expression of the NAC (NAM, ATAF1/2, and CUC2) transcription factor (TF) family genes TaNAC29 and TaNAC21/22 is induced. The TF genes TaNAC29 and TaNAC21/22 in the presence of SnToxA induce the development of the susceptibility of wheat plants to S. nodorum SnB, associated with a decrease in the oxidative burst during the early stage of infection. Thus, our study provides new data on the role of the NEs SnTox3 and SnToxA in manipulating ABA signaling in the development of the susceptibility of wheat to S. nodorum. Deepening our knowledge in this area will be instrumental for developing new strategies for breeding programs and will contribute to the development of environmentally friendly sustainable agriculture.

Increasing the efficiency and capacity of nuclear power units is a promising direction for the development of power generation systems. Unlike thermal power plants, nuclear power plants operate at relatively low temperatures of the steam working fluid. Due to this, the thermodynamic efficiency of such schemes remains relatively low today. The temperature of steam and the efficiency of nuclear power units can be increased by integrating external superheating of the working fluid into the schemes of steam turbine plants. This paper presents the results of a thermodynamic analysis of thermal schemes of NPPs integrated with hydrocarbon-fueled plants. Schemes with a remote combustion chamber, a boiler unit and a gas turbine plant are considered. It has been established that superheating fresh steam after the steam generator is an effective superheating solution due to the utilization of heat from the exhaust gases of the GTU using an afterburner. Furthermore, there is a partial replacement of high- and low-pressure heaters in the regeneration system, with gas heaters for condensate and steam superheating after the steam generator for water-cooled and liquid-metal reactor types. An increase in the net efficiency of the hybrid NPP is observed by 8.49 and 5.11%, respectively, while the net electric power increases by 93.3 and 76.7%.

Improvement of energy efficiency in technological processes at industrial enterprises is one of the key areas of energy saving. Reduction of energy costs required for the production of energy-intensive products can be achieved through the utilization of waste heat produced by high-temperature thermal furnace units. Generation of electric power based on the waste heat using power cycles with working fluids that are not conventional for large power engineering, may become a promising energy saving trend. In this paper, thermodynamic analysis and optimization of power cycles for the purposes of waste heat recovery are performed. The efficiency of combining several power cycles was also evaluated. It has been established that the combination of the Brayton recompression cycle on supercritical carbon dioxide with the organic Rankine cycle using R124 allows for greater electrical power than steam-power cycles with three pressure circuits under conditions where the gas temperature is in the range of 300–550 °C and the cooling temperature of is up to 80 °C. Additionally, when cooling gases with a high sulfur and moisture content to 150 °C, the combined cycle has greater electrical power at gas temperatures of 330 °C and above. At enterprises where the coolant has a high content of sulfur compounds or moisture and deep cooling of gases will lead to condensation, for example, at petrochemical and non-ferrous metallurgy enterprises, the use of combined cycles can ensure a utilization efficiency of up to 45%.

The review presents the main functions of oxalates (oxalic acid and its salts) in physiological processes in plants. The participation of endophytic bacteria, oxalotrophs and/or oxalic acid producers, in the regulation of plant responses to the effects of unfavorable environmental factors of biotic and abiotic nature is considered. A conclusion is made about the prospects for the development of a new direction in the study of the role of endophytic bacteria in the formation of oxalate-mediated adaptive potential in plants.

The SnTox1 effector is a virulence factor of the fungal pathogen Stagonospora nodorum (Berk.), which interacts with the host susceptibility gene Snn1 in a gene-for-gene manner and causes necrosis on the leaves of sensitive wheat genotypes. It is known that salicylic acid (SA), jasmonic acid (JA) and ethylene are the key phytohormones involved in plant immunity. To date, effectors of various pathogens have been discovered that can manipulate plant hormonal pathways and even use hormone crosstalk to promote disease development. However, the role of SnTox1 in manipulating hormonal pathways has not been studied in detail. We studied the redox status and the expression of twelve genes of hormonal pathways and two MAPK genes in six bread wheat cultivars sensitive and insensitive to SnTox1 with or without treatment by SA, JA and ethephon (ethylene-releasing agent) during infection with the SnTox1-producing isolate S. nodorum 1SP. The results showed that SnTox1 controls the antagonism between the SA and JA/ethylene signaling pathways. The SA pathway was involved in the development of susceptibility, and the JA/ethylene pathways were involved in the development of wheat plants resistance to the Sn1SP isolate in the presence of a SnTox1-Snn1 interaction. SnTox1 hijacked the SA pathway to suppress catalase activity, increase hydrogen peroxide content and induce necrosis formation; it simultaneously suppresses the JA and ethylene hormonal pathways by SA. To do this, SnTox1 reprogrammed the expression of the MAPK genes TaMRK3 and TaMRK6 and the TF genes TaWRKY13, TaEIN3 and TaWRKY53b. This study provides new data on the role of SnTox1 in manipulating hormonal pathways and on the role of SA, JA and ethylene in the pathosystem wheat S. nodorum.

Cytokinins (CKs) and abscisic acid (ABA) play an important role in the life of both plants and pathogenic fungi. However, the role of CKs and ABA in the regulation of fungal growth, development and virulence has not been sufficiently studied. We compared the ability of two virulent isolates (SnB and Sn9MN-3A) and one avirulent isolate (Sn4VD) of the pathogenic fungus Stagonospora nodorum Berk. to synthesize three groups of hormones (CKs, ABA and auxins) and studied the effect of exogenous ABA and zeatin on the growth, sporulation and gene expression of necrotrophic effectors (NEs) and transcription factors (TFs) in them. Various isolates of S. nodorum synthesized different amounts of CKs, ABA and indoleacetic acid. Using exogenous ABA and zeatin, we proved that the effect of these hormones on the growth and sporulation of S. nodorum isolates can be opposite, depends on both the genotype of the isolate and on the concentration of the hormone and is carried out through the regulation of carbohydrate metabolism. ABA and zeatin regulated the expression of fungal TF and NE genes, but correlation analysis of these parameters showed that this effect depended on the genotype of the isolate. This study will contribute to our understanding of the role of the hormones ABA and CKs in the biology of the fungal pathogen S. nodorum.

The effect of chitosan conjugates with caffeic (ChCA) and ferulic (ChFA) acids in combination with Bacillus subtilis bacteria on the transcriptional activity of PR protein genes and proteome changes in potato plants during infection with Phytophthora infestans (Mont.) de Bary was studied. Plants grown from mini tubers of the Luck variety were sprayed with solutions of ChCA and ChFA, suspension of B. subtilis bacteria strains 26D and 11 VM, composites of ChCA of ChFA together with bacteria. 3 days after treatment, some of the plants were infected with P. infestans. A decrease in the degree of development of the pathogen of late blight on potato leaves in all treatment options was revealed. The maximum protective effect was manifested when plants were treated with bacteria B. subtilis strain 26D in combination with conjugates of chitosan and oxycinnamic acids. The mechanisms of increasing the resistance of potato plants to P. infestans were associated with the activation of transcriptional activity of genes encoding the main protective protein (PR‑1), chitinase (PR‑3), thaumatin-like protein (PR‑5), protease inhibitor (PR‑6), peroxidase (PR‑9), ribonuclease (PR‑10). The revealed activation of the expression of marker genes of systemic acquired resistance and induced systemic resistance under the influence of joint treatment of plants with B. subtilis and chitin conjugates with oxycinnamic acids indicate the synergistic development of protective reactions in potato plants in this variant. By the method of two-dimensional electrophoresis of S. tuberosum leaf proteins followed by MALDI-TOF analysis, 12 proteins were identified, the presence of which in the leaves differed depending on the variant of the experiment. In all treatment variants, suppression of serine-threonine protein phosphatase activity was observed, reflecting the development of the hypersensitivity reaction. Different variants of the experiment formed weakly expressed clusters, which indicates multiple mechanisms of regulation of the synthesis of protective proteins involved in the reaction to treatment with bacteria, chitosan conjugates and infection with P. infestans.

Small nuclear power plants can provide a stable, carbon-free energy supply to civil infrastructure and industrial enterprises in remote regions isolated from unified energy systems. More than 70 projects of small modular reactors are currently being developed by IAEA member countries; several low-power power units are already supplying thermal and electrical energy to consumers. One of the main limitations standing in the way of widespread dissemination of this technology is the high specific capital cost of a low-power nuclear power plant; therefore, new scientific and technical solutions are needed in this industry. Increasing the thermodynamic efficiency of power cycles of small modular reactors can become a driver for reducing the cost of supplied electrical energy. This paper presents the results of a comprehensive thermodynamic analysis of existing and promising power cycles for small modular reactors. In addition to traditional steam power cycles, cycles using non-traditional working fluids, including carbon dioxide, freons, and helium cycles, are considered. Optimal sets of thermodynamic parameters were determined to ensure maximum net efficiency of electricity production. For water-cooled reactor plants, a maximum efficiency of 33.5% at an initial temperature of 300 °C could be achieved using a steam turbine cycle. It was revealed that for reactor plants with liquid metal and liquid salt coolant in the range of initial temperatures above 550–700 °C, the maximum thermal efficiency was provided by the Brayton recompression cycle with a carbon dioxide coolant: the net electrical efficiency exceeded the level of steam turbine plants, with intermediate superheating of the steam, and could reach a value of 49.4% at 600 °C. This makes the use of these cycles promising for low-power nuclear power plants with a high initial temperature. In small gas-cooled reactor plants with a helium coolant, the use of a binary cycle consisting of a helium Brayton cycle and a steam-powered Rankine cycle provided an efficiency of 44.3% at an initial helium temperature of 700 °C and 52.9% at 1000 °C. This was higher than in the Brayton cycle with a recuperator, with a minimum temperature difference in the heat exchanger of 20 °C: the efficiency was 40.2% and 52%, respectively. Also, the transition to power cycles with non-traditional working fluids will lead to a change in the operating conditions of turbomachines and heat exchangers.

Beneficial endophytic bacteria can suppress the development of insect pests through direct antagonism, with the help of metabolites, or indirectly by the induction of systemic resistance through the regulation of hormonal signaling pathways. Lipopeptides are bacterial metabolites that exhibit direct antagonistic activity against many organisms, including insects. Also, lipopeptides are able to trigger induced systemic resistance (ISR) in plants against harmful organisms, but the physiological mechanisms of their action are just beginning to be studied. In this work, we studied ten strains of bacteria isolated from the tissues of wheat and potatoes. Sequencing of the 16S rRNA gene showed that all isolates belong to the genus Bacillus and to two species, B. subtilis and B. velezensis. The genes for lipopeptide synthetase – surfactin synthetase (Bs_srf ), iturin synthetase (Bs_ituA, Bs_ituB) and fengycin synthetase (Bs_fenD) – were identified in all bacterial isolates using PCR. All strains had high aphicidal activity against the Greenbug aphid (Schizaphis graminum Rond.) due to the synthesis of lipopeptides, which was proven using lipopeptiderich fractions (LRFs) isolated from the strains. Endophytic lipopeptide-synthesizing strains of Bacillus spp. indirectly affected the viability of aphids, the endurance of plants against aphids and triggered ISR in plants, which manifested itself in the regulation of oxidative metabolism and the accumulation of transcripts of the Pr1, Pr2, Pr3, Pr6 and Pr9 genes due to the synthesis of lipopeptides, which was proven using LRF isolated from three strains: B. subtilis 26D, B. subtilis 11VM, and B. thuringiensis B-6066. We have for the first time demonstrated the aphicidal effect of fengycin and the ability of the fengycin-synthesizing strains and isolates, B. subtilis Ttl2, Bacillus sp. Stl7 and B. thuringiensis B-6066, to regulate components of the pro-/antioxidant system of aphid-infested plants. In addition, this work is the first to demonstrate an elicitor role of fengycin in triggering a systemic resistance to S. graminum in wheat plants. We have discovered new promising strains and isolates of endophytes of the genus Bacillus, which may be included in the composition of new biocontrol agents against aphids. One of the criteria for searching for new bacteria active against phloem-feeding insects can be the presence of lipopeptide synthetase genes in the bacterial genome.

The effect of Bacillus velezensis M66 and Bacillus subtilis 26D bacteria on the resistance of potato plants to the necrotrophic fungus Alternaria solani (the causative agent of early blight) was studied. The accumulation of viable bacterial cells of these strains in the internal tissues of the potato stem, roots, and tubers over a long period of time was demonstrated for the first time. A significant reduction in the area affected by the early blight on leaves inoculated with plant endophytes, as well as inhibition of the pathogen growth under the action of bacterial strains, was detected, which can be explained by the synthesis of lipopeptide antibiotics (the genes responsible for the synthesis of which were found by the PCR method) and proteolytic enzymes (the activity of which was demonstrated in vitro). The formation of plant resistance under the influence of inoculation with B. subtilis 26D and B. velezensis M66 was accompanied by an accumulation of hydrogen peroxide in the first hours after plant infection with A. solani spores and by a decrease in this index at the late stages of pathogenesis due to an increase in the activity of catalase and peroxidases. Limitation of the fungus spread was accompanied by an increase in the activity of proteinase inhibitors in plants, which probably decreased the negative effect of proteolytic enzymes of the necrotrophic pathogen A. solani. It can be assumed that the inoculation of plants with bacterial cells of the B. velezensis M66 strain contributed to the formation of resistance of potato plants to the early blight by efficient priming of the phytoimmune potential, which is comparable to the B. subtilis 26D strain (successfully used in the field conditions), an active component of the Fitosporin-M biopreparation.

The article presents the results of a study of the mixing regime of a small lake, the wind effect on the water column of which is significantly weakened by the forest cover of the adjacent coastal area. Temperature measurements using a chain of thermistors were carried out during two open seasons, in 2021 and 2023. The main attention was paid to periods of night cooling, since it is this mechanism that can be considered prevalent in the mixing of the water column and the formation of a convectively mixed surface layer. Wherein, in the summer months, despite significant nighttime heat fluxes on the surface, complete mixing does not occur. The analysis of the dynamics of the temperature profile and the calculation of the efficiency of mixing were carried out using the integral energy method, based on the identification of mixing episodes and calculations of the background potential energy and buoyancy flux. For mixing efficiency, estimates of 0.45 and 0.49 were obtained for two seasons, significantly exceeding the canonical value of 0.17. It was also revealed that the efficiency value depends on the shape of the density profile and, in particular, on the thickness of the mixed layer

Currently, the search for B. thuringiensis strains to be used as biological control agents is based on their toxicity to insects in laboratory tests. At the same time, a number of strains of these bacteria are able to exist in symbiotic relationships with host plants, including being endophytes. The ability of B. thuringiensis strains to penetrate into the internal tissues of plants was evaluated by counting colony-forming units (CFU) of microorganisms 7 days after inoculation of sterile potato plants in test tubes; insecticidal activity was tested on larvae of the III instar obtained from overwintered adults of the Colorado beetle collected from fields in the Chishminsky and Iglinsky districts of Bashkortostan. It was shown that the strain of B. thuringiensis B-5351, which inhabits the surface (50.01 ± 8.10 CFU × 105/g) and internal tissues (38.92 ± 9.62 CFU × 105/g) of plant shoots, but has less insecticidal activity than the strain B. thuringiensis B-5689, which exhibits high insecticidal activity and colonizes mainly plant roots (25.37 ± 3.82 CFU × 105/g), reduced colonization of potato crops by the Colorado potato beetle, and also increased the yield of tubers in a 2-year experiment (2020–2021). Under the influence of B. thuringiensis B-5351, a decrease in the number of larvae of early age was observed, in contrast to B. thuringiensis B-5689, which caused longer metamorphosis processes. Apparently, the effect of B. thuringiensis B-5351 was the death of insects. It is important that processing B. thuringiensis B-5351 contributed to a significant decrease in the number of late-instar larvae on crops treated with this strain as well as the degree of defoliation of plants by the pest, which was not observed with the action of B. thuringiensis B-5689. On plots treated with B. thuringiensis B-5351, the yield of commercial tubers and the total yield increased. A method is proposed for studying the endophytic potential of strains in relation to the terrestrial part of plants to search for biocontrol agents as a basis for creating algorithms for constructing microbiomes in agrocenoses.

The effect of bacteria Bacillus velezensis strain М66 on resistance of potato plants to oomycete Phytophthora infestans (Mont.) de Bary that causes late blight disease was investigated. For the first time, a rise in the number of endophytic bacteria B. velezensis М66 in internal tissues of plants after infection with the pathogen as compared with plants solely inoculated with bacteria was shown. A considerable reduction in the area showing the symptoms of late blight disease was shown irrespective of virulence of the used strain of pathogen. Formation of plant resistance under the effect of B. velezensis М66 cells was accompanied by activation of trypsin inhibitor and peroxidases; accumulation of hydrogen peroxide and transcripts of genes encoding inhibitors of proteinases, β-1,3-glucanase, and anionic peroxidase; and reduction in the level of transcripts of gene PR1: a marker of the development of salicylate-depending reactions. As to the system of RNA interference, it was shown that aggressive strain P. infestans Sn stimulated accumulation of transcripts of the gene encoding Dicer-like protein (DCL) in potato plants, whereas less aggressive strain P. infestans 1840 activated genes DCL and Ago4. Plant treatment with bacteria B. velezensis М66 promoted accumulation of gene Ago1 transcripts both in healthy and infected plants. Inoculation of plants with bacteria and subsequent infection with oomycete promoted accumulation of transcripts of all the examined genes involved in the system of RNA interference. Thus, inoculation of plants with cells of endophytic bacteria B. velezensis strain M66 promotes formation of resistance to oomycete P. infestans by means of efficient priming of plant immune potential.

The review is devoted to the study of the relationship between endophytic bacteria Bacillus spp. with plants, the nature and mechanisms of manifestation of response reactions of a plant organism in a community with bacteria to environmental stress factors. Information is presented on the influence of bacterial endophytes on the formation of mutualistic relationships between plants and other microorganisms.The conclusion is made about the need for an integrated approach to studying the effect of endophytic bacteria on a plant organism under the action of various stress factors and in the conditions of its interaction with other microorganisms.