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Introduction. The presented article reveals the visual background of the causes of the military conflict on the Khalkhin Gol river in 1939 on the eve of the 85th anniversary of these events, and the authors focus the reader’s attention on the importance of timely demarcation and delimitation of the borders between participants in international relations and aim to analyze Russian-language and Japanese retrospective maps of the 1900s-1930s visualizing the Khalkha-Manchurian border area in the zone of the Khalkhin Gol river and Lake Buir-Nur, giving a description of the border line between Khalkha and Barga in the conflict zone. Materials and methods. The study is based on the analysis of twelve cartographic sources with diagrams included into the secret reports of the Trans-Amur district officers, the maps of famous researchers and cartographers of the imperial and Soviet periods, the diagrams from the journal “Bulletin of Manchuria” and the Japanese maps of the 1930s. An interdisciplinary approach has been applied, combining methods of historical and geographical sciences, namely historical-typological, historical-systemic, comparative-historical and historical-genetic methods, a retrospective approach, source analysis, cartographic method, as well as geoinformation analysis. Results. The differences in the depiction of the Khalkha-Barga border, the Lake Buir-Nur and the Khalkhin-Gol river on the maps of different periods and origin were revealed. The Khoshuns (principalities) affected by the military actions of 1939 have been identified. It has been established that the Japanese maps of the 1930s are of high cartographic quality and the degree of information load requires additional study with the involvement of an interpreter. The analysis of retrospective maps demonstrates the evolution of the ideas about the Khalkha-Manchurian border area and emphasizes the importance of the cartographic sources in the study of historical territorial disputes. Conclusions. The study contributes to the understanding of the preconditions of the conflict on the Khalkhin Gol river and opens up prospects for further study of cartographic materials of this period.

Relevance. The commissioning of a large number of new fields with limited amount of initial geological and physical data. To fill in the missing data, the selection of object-analogs is carried out. From the correct choice the selected development system will depend. But according to the established practice, the choice of analogues is carried out only by the expert method, based on the search for the geographically closest objects being developed. The effectiveness of the chosen development strategy depends on the selected analogues, which in their turn will minimize the risks of oil companies during the operation of assets. Aim. Development of an algorithm for qualitatively selection of the best object-analogue of the project field, taking into account the verification of the selected analogues. Methods. Evaluation and analysis of the necessary data to define the degree of similarity of reservoir development by the methods of mathematical statistics and machine learning. Results. The authors describe the problem in the selection of objecvt-analogues and the existing approaches to its solution. The paper introduces the prospects and possibilities of applying the accumulated experience in the developing of new assets and provides an algorithm for the selection of analogues based on a qualitative assessment of geological parameters and quantitative assessment of the degree of similarity of geological and physical characteristics of the object. The results obtained show that the method allows you to quickly find analogues from massive databases, and has a high degree of correlation with the variants of deposits agreed upon by the state expertise for the development of hydrocarbon fields. The authors proposed a way of applying the analogy method to predict the missing data.

Abstract Kalb–Ramond gravity is expected to show the signatures of the low energy limit of the Lorentz violating extension of the standard model of particle physics. To understand the theory further, we study the circular geodesics belonging to a class of exact solutions [found recently by Lessa, Silva, Maluf, Almeida (LSMA)] by posing them as a Hamiltonian dynamical autonomous system. The analysis on the phase space for relevant values of the Lorentz violating parameters reveals for the first time a wealth of novel information that include prediction of homoclinic orbits, saddle points, separatrices that are not available from the conventional analysis. Their image on the actual physical space is discussed.

Relevance. The need to enhance oil recovery from horizontal wells under complex geological and technical conditions. The use of more accurate numerical models, including chemical reactions and the modeling of complex fracture systems, allows optimization of well stimulation, significantly improving both economic and technological efficiency. This is particularly important for developing low-permeability reservoirs and operating under challenging conditions. This work examines the numerical modeling of well inflow stimulation methods using various approaches. For acid treatment modeling, approaches based on changes in well productivity and the use of chemical reactions in the hydrodynamic model were applied. The quality of forecasted technological performance was assessed using real data from an analogous well. As a result, in the case of a real field with extended horizontal wells, additional oil production was achieved through different approaches to acid treatment modeling. Multistage hydraulic fracturing was modeled using planar and discrete fracture models, with only minor discrepancies in the hydrodynamic modeling results between these methods. Aim. To assess the effectiveness of various numerical modeling approaches for well inflow stimulation methods, such as acid treatment and aimed at optimizing oil production from extended horizontal wells. Methods. Numerical models were used to evaluate the effectiveness of stimulation methods, focusing on changes in productivity, the impact of chemical reactions, and sensitivity analysis of treatment parameters. Results and conclusions. It was found that the use of negative skin factors significantly increases oil production compared to models accounting for chemical reactions. Sensitivity analysis of acid volume and concentration helped identify optimal parameters for enhancing acid treatment efficiency. Both modeling approaches (planar and discrete fracture systems) yielded comparable results. Multistage hydraulic fracturing demonstrated a 25000-ton increase in oil production over three years, making it a more effective method than acid treatment.

A new derivatization reagent, phthalylglycyl chloride (PG-Cl), for the analysis of urinary amino acids was demonstrated using reversed-phase ultra-high performance liquid chromatography coupled to electrospray ionization-quadrupole-time-of-flight mass spectrometer. The study compares the limits of detection and quantification for different sample preparation techniques with the commonly used and effective method of derivatization using dansyl chloride. The stability of the derivatives was investigated, and the study includes an example of urinary amino acid analysis using PG-Cl derivatization. The optimal values for pH, temperature, and concentration of the derivatization reagent were established. Limits of quantification in the range of 0.5–500 µg/mL were obtained for different amino acids. The possibility of phthalylglycyl chloride usage for non-target screening applications and targeted analysis of amino acids in urine was discussed. An advantages and issues of PG-Cl in comparison with commonly used acyl-chlorides (FMOC-Cl and DNS-Cl) provided and discussed.

A brief analysis of studies on logging equipment has allowed us to conclude that it is necessary to further study the degree of influence of silvicultural and taxation indicators of the stand, containing quantitative data on the trees harvested and remaining for rearing, on the productivity of the harverster. The degree of influence of quantitative indicators of the stand on the work of the harvester is random, which is due to the infinitely wide variety of options for the spatial arrangement of trees in forest swathes. The article presents the results of a production experiment to assess the impact of the quantitative characteristics of the forest stand on the duration of individual elements of the cycle time of the harvester. The analyzed factors included the total number of trees per 1 hectare and the proportion of the felled component of the stand. These factors play a significant role in assessing the shift and hourly productivity of machines, however, when analyzing the duration of a number of elements of cycle time of manipulator machines, the importance of these indicators is underestimated by many researchers and, in order to increase the convenience and simplicity of calculations, these indicators are not used in justifying labour costs. Both factors have been considered at three levels of variation. As a result, the significant influence of the analyzed factors on the duration of 3 independent elements of cycle time of the machine (pointing the manipulator at the tree, hauling the trunk to the processing zone and moving the harvester between operating positions) has been proven. The experiment has been carried out using the Silvatec 8266TH harvester under conditions of its operation in the swathes characterized by various silvicultural and taxation indicators. The sequence of conducting the production experiment and statistical processing of the obtained data has been shown. The analysis of variance has allowed us to conclude that it is necessary to comprehensively take into account the analyzed factors when assessing each technological operation. The results can be used to improve mathematical relationships in calculating productivity and labour costs when designing logging operations.

Aim – to investigate the associations of rs3134069, rs4355801 and rs3102735 polymorphisms in the TNFRSF11B gene with knee osteoarthritis in postmenopausal women. Material and methods. 483 postmenopausal women were examined, including 157 patients with knee osteoarthritis. The remaining 326 women had no signs of joint disease and formed the control group. All examined women were tested using real-time polymerase chain reaction for single nucleotide polymorphisms rs3134069, rs4355801 and rs3102735 in the TNFRSF11B gene. Results. It was found that genotypes distribution of polymorphisms rs3134069, rs4355801 and rs3102735 in the TNFRSF11B gene in the total group of examined women (n = 483) corresponded to the Hardy – Weinberg law (p 0.05). The analysis of the polymorphic variants’ frequency in the TNFRSF11B gene revealed an increased frequency of AC or CC genotypes of rs3134069 polymorphism in patients with knee osteoarthritis (OR = 1.91; 95% CI: 1.10–3.32; p = 0.030). Also, the allele C frequency of the above-mentioned polymorphism was increased among patients with osteoarthritis (OR = 1.78; 95% CI: 1.06–2.99; p = 0.040). No association with knee osteoarthritis was found for two other studied polymorphisms in the TNFRSF11B gene – rs4355801 and rs3102735 (p 0.05). Conclusion. The increased frequency of genotypes AC or CC registration, as well as allele C of rs3134069 polymorphism in the TNFRSF11B gene in postmenopausal women with knee osteoarthritis indicates the important role of TNFRSF11B gene mutations in the osteoarthritis development and progression. Further research in this area is of great interest both for a deeper understanding of the disease pathogenesis and for the development of personalized approach in the prevention and treatment of knee osteoarthritis in postmenopausal women.

In recent years, a number of synthetic potentiators of antibiotics have been discovered. Their action can significantly enhance the antibacterial effect and limit the spread of antibiotic resistance through inhibition of bacterial cystathionine-γ-lyase. To expand the known set of potentiators, we developed methods for the synthesis of five new representatives of 6-bromoindole derivatives—potential inhibitors of bacterial cystathionine-γ-lyase—namely potassium 3-amino-5-((6-bromoindolyl)methyl)thiophene-2-carboxylate (MNS2) and its 6-bromoindazole analogs (MNS3 and MNS4), along with two 6-broindazole analogs of the parent compound NL2. Their syntheses are based on 6-bromoindole, 6-bromoindazole and methyl 5-(bromomethyl)-3-((ethoxycarbonyl)amino)thiophene-2-carboxylate as the main building blocks, assembling the rest of the heterocyclic system on their basis at the nitrogen atom. We assessed the ability of the new inhibitors to potentiate the antimicrobial activity of gentamicin.

The development and improvement of effective tools for predicting human behavior in real life through the features of its virtual activity opens up broad prospects for psychological support of the individual. The presence of such tools can be used by psychologists in educational, professional and other areas in the formation of trajectories of harmonious person's development. Currently, active research is underway to determine psychological characteristics based on publicly available data. Such studies develop the direction of "Psychology of social networks". As markers for determining the psychological characteristics of people, various parameters obtained from their personal pages in social networks are used (texts of posts and reposts, the number of different elements on the page, statistical information about audio and video recordings, information about groups, and others). There is a difficulty in obtaining and analyzing a data set this big, as there are non-linear and hidden relationships between individual data elements. As a result, the classic methods of information processing become inefficient. Therefore, in our work to develop a comprehensive model of success based on the analysis of qualitative and quantitative data, we use an approach based on artificial neural networks. The labels of the input records are used to divide the subjects of the study into five clusters using clustering methods (kmeans). In the course of our work, we gradually expand the set of input parameters to include metrics of users' personal pages, and compare the results to determine the impact of qualitative parameters on the accuracy of the artificial neural network. The results reflect the solution of one of the tasks of the research carried out within the framework of the project of the Russian Science Foundation and serve as material for an information and analytical system for automatic forecasting of human life activity based on the metrics of his personal profile in the social network VKontakte.

The objective of our study was to investigate the genetic predictors of self-regulation and related characteristics indicative of a higher level of rational behavior control. The study 107 female participants aged between 22 and 52 years, with an average age of 33.5 years (Russian Federation). In order to measure level of self-regulation and other characteristics corresponding to a higher level of rational behavioral control the following psychological tests were employed: the “Differential Type of Reflection” questionnaire (Leontyev D.A.), the “Style of Self-Regulation of Behavior” questionnaire (Morosanova, Kholopova, 1995), and the Test of Life-Meaning Orientations (D.A. Leontyeva, 1988). Genotyping was use to examine polymorphisms of the COMT, DRD2 genes. Our findings demonstrate significant differences in the level of systemic reflection among carriers of different genotypes of the DRD2 and COMT genes. The highest level of systemic reflection in carriers of the CC genotype for the DRD2 gene and a heterozygous variant of the COMT gene suggests a balance between the elevated dopaminergic activity characteristic of the CC DRD2 genotype and moderate COMT activity, fostering optimal dopamine metabolism.

Background. Remote work has been gaining popularity for a long time. With the outbreak of the COVID-19 pandemic, remote work has become a necessity for many people. However, the personality traits of people for whom remote work is suitable are poorly understood. Objectives. The study focuses on the personality traits of successful freelancers working remotely. Study Participants. 184 Freelancers (115 females, 69 males, aged from 14 to 60) were recruited from Advego.com. Freelancers were divided into two groups of beginners and experts, based on the number of tasks completed. Groups were compared with each other. The group of experts was also compared with a group of 98 females (aged from 16 to 72) who were not freelancers. Methods. An empirical study was carried out using a five-factor personality questionnaire by H. Tsuji in the version of A.B. Khromov. Results. Significant differences were found between expert freelancers and women of different professions for the following personality traits: extraversion (p = 0.0001), agreeableness (p = 0.0001), openness to experience (p = 0.0001). The hypothesis that freelancers have a higher level of conscientiousness than non-freelance women was not confirmed. Conclusions. The personality traits of freelancers who are successfully adapted to remote work are revealed including lower levels of extraversion, agreeableness, and openness to experience. The results obtained can be used to select staff for remote work.

Background. Currently, psychological knowledge integrates theories on codependent behavior, advancing our understanding of this phenomenon. However, empirical research is lacking to understand its specific manifestations in relation to different types of addiction. Objective. To identify the features of self-attitude and reflection in codependent women. Design. The study included 233 women (ages 18–70), including 102 in relationships with a person addicted to alcohol, drugs, or suffering from a non-chemical addiction). The study was conducted using the following methods: Self-Attitude Questionnaire (Stolin & Panteleev, 1988); Differential Type of Reflection Questionnaire (Leontiev, 2009); and Codependency Self-Inventory Scale (CSIS; Weinhold & Weinhold, 1989; translated by A. G. Cheslavskaya, 2002). Results. Significant differences were observed in self-attitude and reflection. Women with high codependency have lower self-esteem and tend to underestimate their abilities, compared to the control group. They also exhibit a lower sense of control over their lives, lower self-consistency; they tend to focus on their weaknesses and shortcomings and are more inclined to self-blame. Quasi-reflexivity is more common in codependent women who have relationships with non-chemical addicts or do not identify an addict in their lives. Conclusion. There are significant differences in self-attitude and reflection between the control group and subgroups of women in relationships with different types of addicts; the same differences were observed in comparison of women with low and high codependency levels. The study contributes to a better understanding of the psychological mechanisms underlying codependent behavior in women and has implications for future research and clinical practice.

The article presents the results of a comparative analysis of algorithms for automatic interpretation of tectonic faults based on seismic data recorded in various seismogeological conditions. For each type of geological section (platform, salt tectonics, marine data), a cube of the probability of violations by an analytical algorithm and using trained neural networks was calculated.

A mathematical model of the in-line control of the insulation resistance state for cathodically polarized main pipelines according to electrometry data is considered. The relevance of the work is caused by the opportunity to create in-line internal isolation defects indicators of the main pipelines for transported liquids that are good conductors and expand the functionality of monitoring and controlling cathodic protection systems of the main pipelines. Features of the mathematical model are: consideration of the electric conductivity of transported liquid influence on electric field distribution; consideration of the influence of external and internal insulating coating resistance; use of the electric field of an in-line diagnostic probe for quality control of internal insulation. Practical significance consists in the development of modeling methods for control subsystems of main pipeline protection against corrosion and the development of special mathematical and algorithmic support systems for monitoring and controlling the operating modes of the cathodic protection station of main pipelines.

The Eurasian otter (Lutra lutra) is a widespread semiaquatic carnivorous mammal in Eurasia. The nominate subspecies (L. l. lutra) occupies vast areas between Western Europe and the Russian Far East, but its phylogeography and genetic diversity are still unclear across Northern Eurasia. Another subspecies, L. l. meridionalis, located in the Caucasus mountains, is morphologically almost identical to L. l. lutra but needs genetic revision. We compared the genetic diversity of Eurasian otters from Russia and Armenia using a mtDNA fragment (820 bp) and 20 autosomal microsatellite loci (N = 117). A total of 32 haplotypes were observed with 17 novel haplotypes. The MtDNA median-joining network was mostly star-shaped with a branch of haplotypes from Far Eastern Russian otters. Both mtDNA analysis and Bayesian clustering of microsatellite data indicated that Far Eastern otters are more genetically differentiated than European and Siberian otters (Φst = 0.565 and 0.467; Rst = 0.306 and 0.256), as well as Caucasian otters (L. l. meridionalis) from Russia and Armenia (Φst = 0.515, Rst = 0.253). Haplotype and nucleotide diversities of Far Eastern otters are also the highest between sample groups (H = 0.882, π = 0.003) and, of Caucasian otters, the lowest (H = 0.464, π = 0.001). Our results suggest Caucasian otters are more similar to the otters from European Russia than to the other groups (but with lower genetic diversity) and lack the genetic variability typical to different subspecies. On the contrary, otters from the Russian Far East are more genetically differentiated, have higher genetic diversity than otters from Europe, and likely belong to another genetic lineage.

On the example of the Alardinskaya mine, the problem of underground mining of seams prone to spontaneous combustion and rock bumps in the conditions of the Kondomsky geological and economic region of the Kuznetsk coal basin is considered. The contradictions in the requirements of regulatory documents for the width of the inter-panel coal pillars in the mining of seams with longwalls in conditions of endogenous fire hazard and in the mining of seams that are dangerous due to geodynamical phenomena are discussed. These contradictions impede the safe mining of seams using traditionally used layouts with the danger of spontaneous combustion of coal and rock bumps. A mining-geomechanical model is presented, which is used for numerical three-dimensional simulation of the stress-strain state of a rock mass with various layouts for longwall panels using the finite element method. The results of the numerical analysis of the stress state of the rock mass immediately before the rock bump are presented, and the main factors that contributed to its occurrence during the mining of the seam are established. A dangerous degree of stress concentration in the coal seam near the leading diagonal entries is shown, especially in conditions of application of abutment pressure from the edge of panels’ gob. The analysis of the features of stress distribution in the inter-panel pillar at different widths is carried out. Recommendations for improving the layout for the development and mining of coal seams that are prone to spontaneous combustion and dangerous in terms of rock bumps in the conditions of Alardiskaya mine have been developed. The need for further studies of the influence of pillars for various purposes, formed during the mining of adjacent seams, on the stress-strain state of previously overmined and undermined seams is shown.

Background. The question of the dynamics of the subjective well-being of students with alexithymia, who represent a risk group for the emergence of maladaptive states in stressful conditions during the COVID-19 pandemic, is considered in connection with their emotional competencies, reflecting the development of personal mechanisms for regulation (self-regulation) of emotions. Objective. The goal is to study and access the impact of the pandemic situation on the subjective well-being of students with symptoms of alexithymia through their emotional competencies. Methods. Toronto Alexithymia Scale by J. Taylor, Subjective Well-Being Scale by A.A. Rukavishnikov, emotional intelligence questionnaire by D.V. Lyusin, a technique for diagnosing emotional barriers in interpersonal communication by V.V. Boyko; Pearson r-test, Kruskal — Wallis H-test were applied. Sample. The study was conducted at the North Caucasus Federal University during the pre-COVID period (2018) and during the pandemic (2021). The sample consisted of 120 students. Results. As a result of a comparative analysis of signs of alexithymia, students found increased difficulties in describing feelings and externality of thinking during the pandemic. There were no significant differences in emotional barriers to communication before the pandemic and during the pandemic among alexithymics. A pronounced reluctance to get emotionally close to other people and a lower level of emotional effectiveness of communication, compared to students without alexithymia, were diagnosed in alexithymics both before and during the pandemic. During the pandemic period, alexithymics have identified: negative dynamics in the ability to understand and manage their own emotions, a noticeable decrease in subjective well-being to a feeling of pronounced emotional discomfort, especially on the scale of the significance of the social environment; negative correlations between the general indicator of alexithymia and difficulties in describing feelings, on the one hand, and satisfaction with everyday life, self-esteem of health, mood stability, ability to manage one's own emotions, on the other hand. Positive correlations with the control of emotional expression, depressive manifestations, absent-mindedness, drowsiness were also identified. Conclusion. The situation of the pandemic had a pronounced negative impact on the subjective well-being of students with alexithymia, mediated by barriers of emotional rapprochement with other people characteristic of alexithymics and a low level of intrapersonal emotional competencies.

Magnesium alloys are promising materials for aviation, automotive engineering, and medicine, however, due to the low resistance to stress corrosion cracking (SCC), their wide application is limited. To create alloys with high resistance to SCC, a comprehensive study of this phenomenon nature is required. Previously, it was suggested that diffusible hydrogen and corrosion products formed on the magnesium surface can play an important role in the SCC mechanism. However, the contribution of each of these factors to the SCC-induced embrittlement of magnesium and its alloys is understudied. Since the influence of diffusible hydrogen on the mechanical properties of metals increases with the strain rate decrease, the study of the strain rate sensitivity of the SCC-susceptibility of magnesium alloys is a critical task. In this work, the authors studied the effect of the strain rate in the range from 5•10−6 to 5•10−4 s−1 on the mechanical properties, the state of the side and fracture surfaces of the as-cast commercially pure magnesium and the AZ31 alloy before and after exposure to a corrosive environment and after removal of corrosion products. The study identified that the preliminary exposure to a corrosive medium leads to the AZ31 alloy embrittlement, but does not affect the mechanical properties and the fracture mode of pure magnesium. The authors found that the AZ31 alloy embrittlement caused by the preliminary exposure to a corrosive medium appears extensively only at the low strain rate and only if the layer of corrosion products is present on the specimens’ surface. The study shows that a change in the strain rate has little effect on the mechanical properties of pure magnesium. The authors concluded that the main cause of the AZ31 alloy embrittlement after soaking in a corrosive medium is the corrosion products layer, which presumably contains the embrittling agents such as hydrogen and residual corrosive medium.

Introduction: the need for effective psychocorrective work with persons convicted of terrorism-related crimes, focused on the correction of these persons, does not raise any doubt. Even greater relevance to the problematic issues considered in the publication is given by the fact that we are talking about females. A not so significant number of convicts in this category, as well as gender psychological characteristics, determine the relevance and significance of aspects of psychological work with women convicted of terrorism-related crimes. Purpose: to determine roles and psychological motives of women in the commission of terrorism-related crimes and disclose methods of their recruitment. The study (83 women convicted of terrorism-related crimes) was conducted in the period from 2014 to 2022 with the help of the following methods: survey and analytical, providing a theoretical analysis of literary sources; empirical, involving the use of psychodiagnostic techniques, author’s questionnaires and questionnaires designed to determine general and socio-psychological characteristics of persons convicted of terrorism. The study covered 83 women convicted of terrorism-related crimes. The analysis of empirical material and scientific sources helps identify key trends of female terrorism, the role, psychological motives of behavior and methods of recruiting potential terrorists. Recommendations for conducting psychocorrective work with the appropriate category of persons are developed. Conclusion: the experience of psychocorrective work of correctional psychologists with women convicted of terrorism-related crimes has not been sufficiently studied due to the small number of this category in correctional institutions; the analysis of scientific data makes it possible to determine key reasons for women’s involvement in terrorism-related crimes, as well as the roles and motives for which they were involved. Understanding mechanisms and motives of women’s involvement in terrorism-related crimes, psychologists of correctional institutions can conduct psychocorrection with this category of convicts.

The issue of the influence of the concentration of the solid phase on the reduction of energy costs and specific energy consumption during pulp transportation is considered. The procedure for preparing slurry from the current enrichment tailings is shown. A scheme is given and the operation of a hydroficated unit for thickening and hydraulic transport of backfill mixtures is described. A diagram of the movement of solid particles in one of the units of the complex – a lamellar thickener is shown. The summary table shows the main design parameters and characteristics of the lamellar thickener. A general view of the laboratory setup used for experimental studies with slurry at various concentrations is given. An example of calculating productivity, density and specific load is presented. The dependence of the shear stress on the velocity gradient was determined for various pulp concentrations. Experimental studies of the process of thickening the production of slurry from the current enrichment tailings have been carried out. It was found that the geometric dimensions of the thickener depend on the concentration of the solid phase in the transported mixture. It is concluded that the flow rate of the slurry and the head loss are functions of the rheological characteristics of the viscoplastic slurry and can be calculated from the derived calculated dependencies.

Abstract Background Electronic cigarettes (e-cigarettes) have become the most common tobacco product used among adolescents in the United States (US). Prior research has shown that peer e-cigarette use was associated with increased risk of own e-cigarette use. Nonetheless, there is little empirical evidence on the directionality of these associations—if peer use predicts own use (peer influence) or if own use predicts peer use (peer selection). Methods We estimated the association between peer and own e-cigarette use among US adolescents 12–17 years of age. We used the cross-lagged model to investigate the mutual relationship between peer and own e-cigarette use over time using data from a population-based longitudinal study, Population Assessment of Tobacco and Health. Stratified analyses were conducted by sex and age subgroups. Results Results from a cross-lagged model showed a statistically significant predicting path leading from peer use at the prior time point to own use at the following time point, but not vice versa. Conclusions We found strong relationships between peer e-cigarette use and own e-cigarette use at within-individual levels. Peer influence paths were more robust than peer selection paths for e-cigarette use. Incorporating peers into prevention and intervention programs may help enhance these strategies.

The enzymatic synthesis of nucleoside derivatives is an important alternative to multi-step chemical methods traditionally used for this purpose. Despite several undeniable advantages of the enzymatic approach, there are a number of factors limiting its application, such as the limited substrate specificity of enzymes, the need to work at fairly low concentrations, and the physicochemical properties of substrates—for example, low solubility. This research conducted by our group is dedicated to the advantages and limitations of using purine nucleoside phosphorylases (PNPs), the main enzymes for the metabolic reutilization of purines, in the synthesis of modified nucleoside analogues. In our work, the substrate specificity of PNP from various bacterial sources (mesophilic and thermophilic) was studied, and the effect of substrate, increased temperature, and the presence of organic solvents on the conversion rate was investigated.

Social network extensions of Heider's balance theory have led to a plethora of adaptations, often inconsistent with Heider and each other. We present a general model that permits the description and testing of specific balance theoretic predictions as Heider had originally proposed them. We formulate balance statements as a comparison of two conditional probabilities of a tie: [Formula: see text], conditioned on 2-path relations [Formula: see text] vs. their counterfactual negation, [Formula: see text]. Here q, r and s, are indices that identify elements in a set of mutually exclusive and exhaustive relations in a multigraph (their sum produces a complete graph). This relaxes the dichotomous assumption of a signed graph. We identify neutral ties distinctive from negative and positive ties and convert the underlying signed graph into a restricted multigraph. The point-biserial correlations of relation q with the count of 2-paths (through relations r and s) describe the difference in conditional probabilities, or the prevalence for any stipulated balance configuration. In total 18 such unique balance correlations are identified for any trichotomous multigraph, although 27 theoretical statements exist. Two major advantages of balance correlations are: direct comparison between any two correlations over time, even if network sizes and densities differ; and the evaluation of specific balanced and unbalanced behaviors and predictions. We apply the model to a large data set consisting of friendly vs hostile relations between countries from 1816 to 2007. We find strong evidence for one of the balance statements, and virtually no evidence for unbalanced predictions. However, there is ample stable evidence that "neutral" ties are important in balancing the relations among nations. Results suggest that prevalence of balance-driven behavior varies over time. Indeed, other behaviors may prevail in certain eras.

Introduction. The territorial organization of Inner Asian polities underwent significant transformations in the first quarter of the 20th century, which resulted in a need for its visualization. Goals. The article attempts to reconstruct the system of key public governance institutions in Mongol-inhabited lands of China in the mentioned period, and to describe tools of their visualization supposed to spot the former across present-day geographical points of the region. So, the study aims to examine some basic institutions of princely power and khoshun administration, religious and aimag/league-level authorities, impacts of the Chinese colonization on Mongol-inhabited territories, investigate sources, tools and methods instrumental in spatial localization and visualization of territorial /governance structures across the lands. Materials and methods. The work focuses on two groups of sources, namely: unpublished materials from P. Dudin’s doctoral thesis (manuscript) (Statehood of Inner Mongolia: Late 19th to Mid-20th Centuries) discussing public governance structures of Mongolian banners (counties); and unique maps of 1914/1925 mentioning khoshuns, aimags and leagues of almost all Mongol-inhabited domains. The research methodology rests on an interdisciplinary approach, methods of historical science to comprise the ideographic (descriptive-narrative) and retrospective ones, a narrative approach, and principles of historicism; knowledge of political science yields an opportunity to employ functional and behavioral approaches. The geographical methods involved rest on the scheme of analysis proposed in works of O. Medushevskaya (1957) and L. Goldenberg (1958), as well as on some analysis of the data generalization degree. Results. The work has reconstructed the early 20th-century system of key Mongolian public governance institutions, outlines how the system of princely power functioned, how khoshun-level administrative bodies took shape and worked, identifies the governance role of religious institutions, while insights into different levels of the administrative/territorial organization facilitates further understanding as to actual scopes of power attributed thereto, and makes it possible to visualize the investigated space with the aid of contemporary tools and techniques. Conclusions. The paper points to the efficiency of the then management system where it was the khoshun that had served — and remained — a key structural element. The latter’s detailed illustrations on V. Surin’s maps make it possible to restore the ancient territorial organization of Mongolia using the GIS system, free access be provided for researchers of the region.

The paper adopts a sociopragmatic approach to the study of emotion processes and investigates discursive traits of the reader’s interest. The field of written popularization was examined to establish how it conceptualizes the reader’s interest through discourse structures. The text materials were obtained experimentally. They consist of 104 pairs of expository text; each of the pairs includes a text published in an academic source and a popular science text created by the participant for provoking the reader’s interest. The comparative methods of empirical discourse analysis are used to identify and describe popularisation strategies. The results show that participants employed four strategies to transform academic texts: reduction N = 94), simplification (N = 81), contextualization (N = 58), and concrete elaboration (N = 17). The strategies tend to present the most significant text ideas, reduce reader’s efforts for processing, and introduce the reader into the discourse-world. The findings suggest that the strategies aim to enhance the optimal relevance and conceptualize reader’s interest through the communicative dimension of relevance.

Relevance. The West Siberian region is currently one of the largest oil and gas provinces in Russia, but the problem of declining production is becoming more frequent there. This phenomenon is caused by various reasons, however the most frequent ones are such as lowering of formation permeability and productivity factor due to various complications of oil production in the bottomhole zone (bottomhole formation zone). As a result, it becomes necessary to carry out work to increase or restore the filtration-capacitance properties of the reservoir. The method of acid treatment of productive reservoirs, which contributes to the intensification of oil inflow into the well, has been actively used in the fields of Western Siberia. However, a significant part of the treatments does not give positive results. Improving the efficiency of acid treatments of wells is one of the main tasks of oil production today, which largely determines the relevance of this study. The purpose of this work is to analyze the degree of expediency of hydrochloric acid treatment in the field and determine the most appropriate method of treatment for carbonate reservoirs of the West Siberian field. Results. The principle of effect and peculiarities of the hydrochloric acid treatment for reservoirs of carbonate structure was studied. The choice and expediency of application of the technology in these conditions was substantiated.

There is a strong belief that hydrogen absorbed by magnesium alloys during corrosion can cause their stress corrosion cracking. One of the characteristic markers indicating the involvement of diffusible hydrogen into the fracture mechanism of metals is the negative strain rate dependence of the embrittlement degree. Recent studies show that the loss of ductility of the ZK60 alloy specimens subjected to a short-term (1.5 h) pre-exposure in a corrosive medium actually decreases with the increasing strain rate. However, after the removal of corrosion products from the surface of the specimens, the strain rate dependence of the ductility loss becomes positive, which indicates the absence of hydrogen in the bulk of the metal. At short-term exposure in a corrosive environment, the deep penetration of hydrogen into a metal could be limited due to the insufficient time for hydrogen diffusion. The paper studies the mechanical behavior of the ZK60 alloy subjected to a longer (12 h) pre-exposure in a corrosive medium followed by tensile testing in air at various strain rates. The authors consider the effect of strain rate, long-term pre-exposure in a corrosive medium, and subsequent removal of corrosion products on the strength, ductility, stages of work hardening, and localized deformation, as well as on the state of the side and fracture surfaces of specimens. It is established that the ductility loss of the specimens pre-exposed in a corrosive medium for 12 h decreases with the increasing strain rate, regardless of whether the corrosion products have been removed from their surface or not. It is shown that in this case, the negative strain rate dependence of the ductility loss is associated not with hydrogen dissolved in the bulk of a metal but with the presence of severe corrosion damage of the specimens’ surface. An explanation for the effect of corrosion damage on the mechanical properties and their strain rate sensitivity is proposed.

The rational design of composites based on graphene/metal oxides is one of the pillars for advancing their application in various practical fields, particularly gas sensing. In this study, a uniform distribution of ZnO nanoparticles (NPs) through the graphene layer was achieved, taking advantage of amine functionalization. The beneficial effect of amine groups on the arrangement of ZnO NPs and the efficiency of their immobilization was revealed by core-level spectroscopy, pointing out strong ionic bonding between the aminated graphene (AmG) and ZnO. The stability of the resulting Am-ZnO nanocomposite was confirmed by demonstrating that its morphology remains unchanged even after prolonged heating up to 350 °C, as observed by electron microscopy. On-chip multisensor arrays composed of both AmG and Am-ZnO were fabricated and thoroughly tested, showing almost tenfold enhancement of the chemiresistive response upon decorating the AmG layer with ZnO nanoparticles, due to the formation of p-n heterojunctions. Operating at room temperature, the fabricated multisensor chips exhibited high robustness and a detection limit of 3.6 ppm and 5.1 ppm for ammonia and ethanol, respectively. Precise identification of the studied analytes was achieved by employing the pattern recognition technique based on linear discriminant analysis to process the acquired multisensor response.