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The article is devoted to the study of the corrosion resistance of steel pile supports made of pipe steel 09Mn2Si (09G2S), under conditions of cyclic wetting (conditional waterline), where conditions are created for the occurrence of corrosion processes at maximum speeds, and also a study of the protective ability of zinc coating applied to the railing (balustrade) of a steel bridge made of carbon steel of normal quality (St3). It was the bridge structures that became the subject of research. We considered the effects of cyclic wetting, wear, and climatic factors on the materials of piled supports, fences, and coatings intended for operation in the marine structure. We investigated the corrosion resistance of the 09Mn2Si steel used as pile supports of offshore structures. We have found that the corrosion rate of the 09Mn2Si steel does not exceed 0.32 mm/year in the zone of cyclic wetting. We have confirmed that the corrosion rate of steel practically does not change in the sections with damaged coatings and does not depend on the area of the uncoated zone. Measuring the electrochemical potential of 09Mn2Si steel, we have found that short-term friction against a solid only weakly affects the corrosion rate of steel in seawater. We have proposed a methodological approach to assessing the service life of hot-dip galvanized coatings on components of steel structures made of carbon steel of normal quality (St3) intended for operation in marine conditions. A forecast of the durability of 120 μm-thick zinc coatings, expected to provide anti-corrosion protection of steel products for 60 years, was made based on the proposed technique.

Nickel-based alloys cover a wide range of oil and gas applications. Alloy EP718 is used as an analogue of alloy 718. The corrosion resistance of EP718 has been determined in severe environmental conditions of NACE level VI over 3 months (175°С, PCO2 = 3.5 MPa, PH2S = 3.5 MPa, pH 3.5, 20% NaCl). The effects of heat treatment on the corrosion rate were studied. The results indicate that the corrosion rate of EP718 in a simulated environment is less than 0.01 mm per year. Stress corrosion cracking could be observed in low quality production and incorrect heat treatment.

The study of carbon dioxide gas exchange of leaves of Prunus laurocerasus L., Laurus nobilis L. and Viburnum tinus L. under various environmental conditions was carried out. The greatest resistance to drought and the ability to absorb CO2 under hydrothermal stress was found in Viburnum tinus plants. It was determined that the inhibition of the processes of CO2 absorption with increasing water scarcity begins in the studied species with a decrease in soil moisture to 35% field capacity. Under conditions of soil drought, the amount of CO2 absorbed by Prunus laurocerasus leaves is reduced by 10 times, Laurus nobilis – by 7 times, Viburnum tinus – by 2 times. The positive carbon dioxide gas exchange of Prunus laurocerasus, Laurus nobilis and Viburnum tinus in the hot dry period, when the amount of CO2 absorption exceeds its release during respiration by 1–5.1, 1.5–3.7 and 1.1–6.2 times, respectively, indicates a significant potential these species for optimizing the urban ecosystems of the southern regions of Russia. The developed predictive models allow us to perform a quantitative assessment of the ability of plants to absorb carbon dioxide under various environmental conditions.

The increase in the corrosiveness of the produced fluid forces to reconsider the attitude towards the assessment of the serviceability and reliability of oil pipes, paying attention to the problems of increasing their corrosion resistance. The paper analyses environmental impact on pipeline made of 9MnSi5 steel after 12 months of operation in the oilfield to assess the residual life of pipeline and determine safe operating conditions. It was found that corrosion damage developed according to the mechanisms of general, pitting corrosion and stress corrosion cracking. Metallographic study has shown cracks of stress corrosion cracking that developed in environments containing carbon dioxide and hydrogen sulfide. Accelerated method of stress corrosion cracking resistance testing was implemented that allows to understand the tendency of steel to this type of cracking and gives a conclusion about the danger of brittle fracture of the pipeline.

Galvanizing is one of the most common methods of corrosion protection. For the deposition of zinc coatings used such methods as gas-thermal deposition, thermal diffusion saturation in powder, hot-dip galvanizing, cladding, and galvanic precipitating during electrolysis. The hot-dip galvanizing is the most common method, which is used in construction, automotive and other industries. Paper presents the results of research of zinc coatings used in sea conditions. The aim of the work was to determine an acceleration factor by comparing the corrosion rate in laboratory conditions with the data from field tests. Laboratory studies were carried out in a salt fog chamber. Samples were periodically removed from chamber to build the dependence of the corrosion rate on the exposure time. Field tests were carried out at the exploitation area. Result of the work is a guide that allows to predict the corrosion rates of zinc coatings using laboratory tests. The advantage of this test method is shorter time of exposure in comparison with field test.

The problem of premature failure of bearings is a common type of failure. In most cases, the destruction occurs due to violation of operating conditions. Since the destruction of bearings is a frequent occurrence, consideration of this special case of destruction in the future will help to avoid such problems. The object of research is the screw compressor bearings destroyed during operation. To identify the causes, a collapsed bearing was examined and a bearing that did not collapse during operation.

Objective: Multidrug-resistant, highly pathogenic Escherichia coli strains are the primary causative agents of intestinal and extraintestinal human diseases. The extensive utilization of antibiotics for farm animals has been identified as a contributing factor to the emergence and dissemination of E. coli strains that exhibit multidrug resistance and possess high pathogenic potential. Consequently, a significant research objective is to examine the genetic diversity of pathogenic E. coli strains and to identify those that may pose a threat to human health. Methods: In this study, we present the results of genome sequencing and analysis, as well as the physiological characterization of E. coli strain APEC 36, which was isolated from the liver of a broiler chicken with generalized colibacillosis. Results: We found that APEC 36 possess a number of mechanisms of antibiotic resistance, including antibiotic efflux, antibiotic inactivation, and antibiotic target alteration/replacement/protection. The most widely represented group among these mechanisms was that of antibiotic efflux. This finding is consistent with the strain's documented resistance to multiple antibiotics. APEC 36 has an extremely rare variant of the beta-lactamase CTX-M-169. Notwithstanding the multitude of systems for interfering with foreign DNA present in the strain, seven plasmids have been identified, three of which may possess novel replication origins. Additionally, qnrS1 , which confers resistance to fluoroquinolones, was found to be encoded in the genome rather than in the plasmid. This suggests that the determinants of antibiotic resistance may be captured in the genome and stably transmitted from generation to generation. Conclusions: The APEC 36 strain has genes for toxins, adhesins, protectins, and an iron uptake system. The obtained set of genetic and physiological characteristics allowed us to assume that this strain has a high pathogenic potential for humans.

The study of molecular and genetic mechanisms of sex determination in the poplar is of interest not only in the fundamental science, but also in the applied research. In landscaping of large settlements, it is advisable to use male individuals of the Populus genus due to their hypoallergenicity and increased resistance to environmental pollution, stress conditions, and pathogens. However, sex determination in poplars is complicated by the complex genetic structure of the sex-determining region of the genome (SDR). In this review, the emergence, evolution, structure, and function of the SDR in the genus Populus are discussed. Current insights into the structure and function of the key regulator of sex selection in poplars, orthologue of the ARR16/ARR17 gene and the possible roles of other genes that are differentially expressed between male and female plants, including microRNAs, in this process are discussed in detail. The great diversity of species and the high complexity of SDR organization justify the need for further study of the molecular mechanisms of sex determination in poplars.

The Cas9 endonuclease of the CRISPR/Cas type IIA system from Streptococcus pyogenes is the heart of genome editing technology that can be used to treat human genetic and viral diseases. Despite its large size and other drawbacks, S. pyogenes Cas9 remains the most widely used genome editor. A vast amount of research is aimed at improving Cas9 as a promising genetic therapy. Strategies include directed evolution of the Cas9 protein, rational design, and domain swapping. The first generation of Cas9 editors comes directly from the wild-type protein. The next generation is obtained by combining mutations from the first-generation variants, adding new mutations to them, or refining mutations. This review summarizes and discusses recent advances and ways in the creation of next-generation genomic editors derived from S. pyogenes Cas9. KEY POINTS: • The next-generation Cas9-based editors are more active than in the first one. • PAM-relaxed variants of Cas9 are improved by increased specificity and activity. • Less mutagenic and immunogenic variants of Cas9 are created., (© 2024. The Author(s).)

Poplar ( Populus ) is a genus of woody plants of great economic value. Due to the growing economic importance of poplar, there is a need to ensure its stable growth by increasing its resistance to pathogens. Genetic engineering can create organisms with improved traits faster than traditional methods, and with the development of CRISPR/Cas-based genome editing systems, scientists have a new highly effective tool for creating valuable genotypes. In this review, we summarize the latest research data on poplar diseases, the biology of their pathogens and how these plants resist pathogens. In the final section, we propose to plant male or mixed poplar populations; consider the genes of the MLO group, transcription factors of the WRKY and MYB families and defensive proteins BbChit1, LJAMP2, MsrA2 and PtDef as the most promising targets for genetic engineering; and also pay attention to the possibility of microbiome engineering.

The white poplar ( Populus alba L.) has good potential for a green economy and phytoremediation. Bioaugmentation using endophytic bacteria can be considered as a safe strategy to increase poplar productivity and its resistance to toxic urban conditions. The aim of our work was to find the most promising strains of bacterial endophytes to enhance the growth of white poplar in unfavorable environmental conditions. To this end, for the first time, we performed whole-genome sequencing of 14 bacterial strains isolated from the tissues of the roots of white poplar in different geographical locations. We then performed a bioinformatics search to identify genes that may be useful for poplar growth and resistance to environmental pollutants and pathogens. Almost all endophytic bacteria obtained from white poplar roots are new strains of known species belonging to the genera Bacillus , Corynebacterium , Kocuria , Micrococcus , Peribacillus , Pseudomonas , and Staphylococcus . The genomes of the strains contain genes involved in the enhanced metabolism of nitrogen, phosphorus, and metals, the synthesis of valuable secondary metabolites, and the detoxification of heavy metals and organic pollutants. All the strains are able to grow on media without nitrogen sources, which indicates their ability to fix atmospheric nitrogen. It is concluded that the strains belonging to the genus Pseudomonas and bacteria of the species Kocuria rosea have the best poplar growth-stimulating and bioaugmentation potential, and the roots of white poplar are a valuable source for isolation of endophytic bacteria for possible application in ecobiotechnology.

Type 1 diabetes mellitus (T1D) is an autoimmune disease caused by the destruction of insulin-producing β-cells in the pancreas by cytotoxic T-cells. To date, there are no drugs that can prevent the development of T1D. Insulin replacement therapy is the standard care for patients with T1D. This treatment is life-saving, but is expensive, can lead to acute and long-term complications, and results in reduced overall life expectancy. This has stimulated the research and development of alternative treatments for T1D. In this review, we consider potential therapies for T1D using cellular regenerative medicine approaches with a focus on CRISPR/Cas-engineered cellular products. However, CRISPR/Cas as a genome editing tool has several drawbacks that should be considered for safe and efficient cell engineering. In addition, cellular engineering approaches themselves pose a hidden threat. The purpose of this review is to critically discuss novel strategies for the treatment of T1D using genome editing technology. A well-designed approach to β-cell derivation using CRISPR/Cas-based genome editing technology will significantly reduce the risk of incorrectly engineered cell products that could behave as a "Trojan horse".

Annual killifish of the genus Nothobranchius are seeing a rapid increase in scientific interest over the years. A variety of aspects surrounding the egg-laying Cyprinodontiformes is being extensively studied, including their aging. Inhabiting drying water bodies of Africa rarely allows survival through more than one rainy season for the Nothobranchius populations. Therefore, there is no lifespan-related bias in natural selection, which has ultimately led to the decreased efficiency of DNA repair system. Aging of the Nothobranchius species is studied both under normal conditions and under the influence of potential geroprotectors, as well as genetic modifications. Most biogerontological studies are conducted using the species Nothobranchius furzeri (GRZ isolate), which has a lifespan of 3 to 7 months. However, the list of model species of Nothobranchius is considerably wider, and the range of advanced research areas with their participation extends far beyond gerontology. This review summarizes the most interesting and promising topics developing in the studies of the fish of Nothobranchius genus. Both classical studies related to lifespan control and rather new ones are discussed, including mechanisms of diapause, challenges of systematics and phylogeny, evolution of sex determination mechanisms, changes in chromosome count, occurrence of multiple repeated DNA sequences in the genome, cognitive and behavioral features and social stratification, as well as methodological difficulties in working with Nothobranchius.

Almost all people become infected with herpes viruses, including herpes simplex virus type 1 (HSV-1), during their lifetime. Typically, these viruses persist in a latent form that is resistant to all available antiviral medications. Under certain conditions, such as immunosuppression, the latent forms reactivate and cause disease. Moreover, strains of herpesviruses that are drug-resistant have rapidly emerged. Therefore, it is important to develop alternative methods capable of eradicating herpesvirus infections. One promising direction is the development of CRISPR/Cas systems for the therapy of herpesvirus infections. We aimed to design a CRISPR/Cas system for relatively effective long-term and safe control of HSV-1 infection. Here, we show that plasmids encoding the CRISPR/Cas9 system from Streptococcus pyogenes with a single sgRNA targeting the UL30 gene can completely suppress HSV-1 infection of the Vero cell line within 6 days and provide substantial protection within 9 days. For the first time, we show that CRISPR/CasX from Deltaproteobacteria with a single guide RNA against UL30 almost completely suppresses HSV-1 infection of the Vero cell line for 3 days and provides substantial protection for 6 days. We also found that the Cas9 protein without sgRNAs attenuates HSV-1 infection. Our results show that the developed CRISPR/Cas systems are promising therapeutic approaches to control HSV-1 infections.