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With regard to the study of the characteristics of electrovortex flows occurring indirect current electric arcs and electroslag smelting furnaces, a method has been developed for calculating the magnetic field in a current-carrying medium based on the calculation of the Biot–Savart–Laplace integral. The developed technique is focused on the use of unstructured grids and does not require a priori information about the shape of the computational domain. The technique has been tested on problems that have an analytical solution, i.e., the calculation of the distribution of the magnetic field in the cylinder and the calculation of the magnetic field of the ring with the current. The distributions of the magnetic field are obtained for the two-dimensional and three-dimensional cases. We used NVIDIA CUDA technology on graphic processor units (GPUs) to speed up calculations. A comparison of the calculation times on various CPUs and GPUs is given.

Aim. To assess the prognostic role of cardiac biomarkers (galectin-3, soluble ST2 (sST2), and N-terminal pro-brain natriuretic peptide (NT-proBNP)) in risk stratification of adverse cardiovascular events (CVEs) in patients with heart failure (HF) after implantation of an automatic implantable cardioverter-defibrillator (AICD) within 12-month follow-up period.Material and methods. The study included 57 patients (men, 41; mean age, 65 (59; 68) years) with coronary artery disease and NYHA class II-III HF with left ventricular ejection fraction of 34 [26; 40]%. All patients were implanted with AICD. Serum levels of NT-proBNP, sST2, and galectin-3 were determined by enzyme immunoassay prior to AICD implantation.Results. It has been established that in order to stratify the risk of unfavorable HF in patients after AICD implantation for 12-month follow-up, all three studied biomarkers can be considered as prognostic factors. Thus, an increase in the level of NT-proBNP ≥1046,6 pg/ml (AUC=0,68; p=0,009), sST2 ≥34,43 ng/ml (AUC=0,78; p

Aim. To study the associations of hypoxia-inducible factor-1 alpha (HIF-1α) gene polymorphism (rs11549465) with the clinical course of heart failure (HF) with reserved ejection fraction (HFpEF) in patients with obesity and moderate and severe obstructive sleep apnea (OSA).Material and methods. The study included 76 men with HFpEF and OSAS. Patients underwent a polysomnography, echocardiography, and a 6-minute walk test. In addition, apnea/hypopnea index was calculated, and the level of N-terminal pro-brain natriuretic peptide (NT-proBNP) was assessed. HIF1A gene polymorphisms (rs11549465) were analyzed using polymerase chain reaction. After 12-month follow-up, the clinical course of HF was assessed.Results. The T/T genotype of the HIF1A gene was associated with a high risk of HF progression (p=0,004), development of supraventricular premature beats (p=0,004) and atrial fibrillation (p=0,039). Carrying the T/T genotype was associated with severe OSA (p=0,006) and increased NT-proBNP (p=0,044), and also correlated with certain echocardiographic characteristics of myocardial remodeling.Conclusion. T/T genotype of the HIF1A gene is associated with OSA severity and increased NT-proBNP, as well as with the severity of left and right heart remodeling. The carriage of this genotype was associated with an unfavorable course of HF and an increased risk of atrial fibrillation in patients with HFpEF and OSA.

Aim. To study approaches to the treatment of chronic heart failure (CHF) with reduced and mid-range left ventricular ejection fraction (LVEF) in patients with arterial hypertension (AH) against the background of obstructive sleep apnea (OSA).Material and methods. The study included 136 patients with CHF and AH. Inclusion criteria for the study: 1) moderate and severe OSA (with an apnea/hypopnea index of more than 15 per hour); 2) II-IV functional class of CHF according to NYHA; 3) the level of brain natriuretic peptide precursor (NT-proBNP) ≥125 pg/ml; 3) LVEF

Aim. To study the relationship of obstructive respiratory disorders during sleep with subclinical development of right ventricular dysfunction and pulmonary hypertension, as well as with the risk of an adverse course of chronic heart failure (CHF) with preserved left ventricular ejection fraction (LVEF).Materials and methods. The study included 86 men with moderate and severe forms of obstructive sleep apnea syndrome (OSAS) (with an apnea/hypopnea index (AHI) > 15 per hour). All patients had abdominal obesity and hypertension. Upon inclusion in the study, all patients underwent polysomnography and echocardiography according to the standard protocol with an additional assessment of the fractional area change in the right ventricular myocardium (ΔSRV) and the right ventricular stroke work index (RVSWI). Also, the content of the N-terminal brain natriuretic peptide precursor (NT-proBNP) in the blood serum was determined by enzyme immunoassay analysis. A six-minute walk test (6MWT) was performed after inclusion in the study and after 12 months of follow-up. Depending on the course of CHF during the follow-up, retrospectively, the patients were divided into 2 groups: with an unfavorable (n = 33) and favorable (n = 53) prognosis.Results. A significant relationship between AHI and ΔSRV, RVSWI, NT-proBNP, and 6MWT was revealed. Based on the results of one-way correlation analysis, it was found that ΔSRV (odds ratio (OR) 2.51; 95% confidence interval (CI) 2.42–3.24; p = 0.0009), NT-proBNP (OR 1.92; 95% CI 1.32–2.78; p = 0.003), and AHI (OR 3.93; 95% CI 2.87–4.11; p = 0.018) were predictors of an adverse course of CHF. In a multivariate analysis, it was found that AHI was an independent predictor of an adverse course of CHF (OR 3.49; 95% CI 2.17–11.73; p = 0.0008), while the addition of NT-proBNP improved risk stratification of an adverse course of CHF (OR 4.66; 95% CI 3.87–13.11; p < 0.0001).Conclusion. The fractional area change in the right ventricular myocardium (ΔSRV) can be considered as a non-invasive marker for determining the emerging right ventricular dysfunction and predicting adverse cardiovascular events in patients with preserved LVEF and OSAS. Moreover, the combined use of echocardiographic (ΔSRV) and laboratory (NT-proBNP) markers can improve risk stratification of CHF progression.

Introduction. Diabetes mellitus, cardiovascular diseases and osteoporosis are linked by common pathophysiological mechanisms.Objective. To evaluate the effect of alendronate bisphosphonate on cardiovascular outcomes in comorbid patients with ischemic heart disease (CHD) associated with type 2 diabetes mellitus (type 2 diabetes) and osteoporosis during a two-year follow-up.Materials and methods. A total of 112 women with comorbid pathology including osteoporosis, coronary artery disease, and type 2 diabetes were examined. The patients' condition was assessed at baseline and prospectively for 24 months with a combined endpoint assessment, including: mortality, readmission for cardiovascular diseases, the development of myocardial infarction (MI), stroke, atrial fibrillation. Women were divided into groups: group 1 (n = 59) included patients who received basic therapy for IHD and type 2 diabetes, group 2 (n = 53) included patients who, in addition to basic therapy for coronary artery disease and diabetes Type 2 was prescribed alendronic acid preparation.Results and discussion. According to the results of two-year follow-up, the patients were divided into two subgroups: patients with a favorable (n = 61) and unfavorable course of coronary artery disease (n = 51). At the same time, during prospective observation, the following was assessed: the frequency of hospitalizations for cardiovascular diseases, the dynamics of the functional class (FC) of exertional angina, the development of MI, stroke, atrial fibrillation, and mortality. A significant association of alendronate therapy with a favorable course of ischemic heart disease (OR = 0.26; 95% CI = 0.18-0.57; p = 0.008), a decrease in the risk of MI (OR = 0.32; 95% CI = 0.11-0.87; p = 0.018) and worsening of FC of exertional angina (OR = 0.4; 95% CI = 0.17-0.91; p = 0.014).Conclusion. Long-term (24 months) use of alendronate is an effective and safe method for the treatment of associated cardiovascular pathology, represented by coronary artery disease, type 2 diabetes and osteoporosis in postmenopausal women, reducing the risk of MI, worsening of FC of exertional angina. These results suggest a more aggressive prescription of alendronate for osteoporotic patients at very high cardiovascular risk.

The authors of the article have analyzed the problem of advanced heart failure (AHF). Despite significant and, it is not an exaggeration to say, revolutionary achievements in clinical pharmacology, cardiac surgery and implantation arrhythmology, the number of patients with chronic heart failure (CHF) in many countries is not decreasing, and in some, for example, in Russia, it is increasing. At the same time, unfortunately, often the immediate and longterm results of the so-called optimal therapy of CHF are disappointing for both the patient and the doctor. In 2007, experts from The Heart Failure Association of the European Society of Cardiology proposed the term AHF to refer to CHF in which optimal drug therapy, as well as cardiac resynchronization therapy, are not effective, which causes repeated hospitalizations and justifies the need for the advanced treatment methods such as heart transplantation and mechanical circulatory support, and/or transition to palliative care. The agreed positions of experts from the established cardiological communities in the Old and New Worlds on the definition, diagnostic criteria and treatment of AHF have been changing over time. Unfortunately, this evolution has not yet arrived at a consensus. The lecture consistently addresses the issues of terminology, diagnosis, prognostic stratification and routing of patients with AHF, as well as short- and long-term strategies for treating these patients.

За последние десятилетия процесс создания новых знаний значительно ускорился, что обусловило появление огромного количества научных публикаций. Это делает обзор даже относительно узкой предметной области крайне затруднительным. Тем не менее новейшие инструменты анализа текстовых данных могут помочь исследователям выполнить эту задачу объективно и с минимальными временными затратами. При помощи методов тематического моделирования мы проводим обзор литературы по 1307 статьям, опубликованным в журнале «Экономика региона» с 2010 г. по 2021 г. Данная работа нацелена на описание основных направлений исследований в журнале, динамики их популярности и взаимосвязи с ключевыми количественными показателями. В ходе анализа мы определили 22 основные темы исследований, варьирующихся от сельского хозяйства и экономической географии до фискальной политики и предпринимательства. Мы оценили, как со временем менялась распространенность этих тем, и определили тематики, которые либо набрали наибольшую популярность с 2010 г. по 2021 г. (+17,61 %, «Пространственная экономика»), либо потеряли ее (-14,58 %, «Экономика инноваций»). Статьи на тему экономики природопользования чаще цитируются (в среднем, 3,64 цитирований на 1 статью), а темы денежно-кредитной политики и бедности наиболее часто встречаются среди работ на английском языке, а также публикаций с иностранной аффилиацией. Работы, вышедшие при поддержке стороннего финансирования, наиболее сконцентрированы в теме «Пространственная экономика» (около 11 % статей), а наименее — в теме «Сельское хозяйство». Полученные результаты, демонстрирующие эволюцию исследований в журнале «Экономика региона», могут помочь авторам найти перспективные направления будущих работ.

The aim. To evaluate the association of fibrinogen (FGB), tumor necrosis factor α (TNFα), interleukin 1β (IL-1β), lipoprotein lipase (LPL), platelet glycoprotein (ITGB3), and transforming growth factor β (TGFB1) genes with the incidence of recurrent myocardial infarction (MI) in patients living in the middle Volga region.Materials and methods. The study included 104 people with recurrent MI compared to 280 people who had just one episode of MI. TNFα (rs1800629), IL1B (rs16944), TGFB1b (rs1800469), FGB (rs1800788), ITGB3 (rs5918) and LPL (rs328) gene polymorphism was determined in all patients using competing TaqMan probes. Association estimation was performed with multivariate logistic regression analysis.Results. Patients with recurrent MI much more often had TNFα, IL1B, TGFB1b, FGB, ITGB3 and LPL allele and genotype polymorphism. Moreover the risk of MI increased significantly in a case of combination of FGB (alleles and genotypes) and TNFα (alleles and genotypes) gene polymorphisms (OR = 4.04, 95% CI = (1.895–8.615), p = 0.0001).Conclusion. Thus, FGB, LPL, TNFα, TGFB1b and ITGB3 gene polymorphism are associated with more severe coronary heart disease and may be a risk factor of recurrent MI development. The dominant total contribution of the FGB (rs1800788) and TNFα (rs1800629) polymorphic genes to the development of recurrent MI in the population of the middle Volga region was revealed.

The authors of this article have analyzed the problem of diagnostic conclusion unification in patients with chronic heart failure (CHF). The root of this problematic situation in which practitioners find themselves is that, despite the large number of different regulatory documents, there is no consensus on what is considered correct and what is wrong when formulating a diagnostic conclusion in a patient with CHF. The many-faced syndrome is designated differently: CHF, congestive heart failure, chronic circulatory failure. There are difficulties in determining the stage of CHF in patients receiving optimal drug therapy or in those who are in a state of compensation after a successful surgical correction. When assessing the functional status in a patient with CHF, a distinct subjectivity should be taken into account in determining which limited physical activity is slight or, conversely, marked, as well as what kind of physical exertion is normal for the patient. This subjectivity naturally leads to low reproducibility of the assessment results of the CHF functional class in the same patient by different doctors. CHF should also be classified according to the value of a left ventricular ejection fraction. The diagnosis should also take into account the state characteristics of a diastolic function of the left ventricle (especially in patients with CHF and preserved left ventricular ejection fraction). The authors give examples of diagnostic conclusions, including cases of comorbid pathology.

The use of sanctions as means of coercion and motivation is not always effective. Ruling elites have an ability to shift the burden on less protected population of the country despite the risk of social unrest. The paper aims to perform an empirical analysis of the impact of economic sanctions on the population of the target countries in general and its individual groups in particular. We test three hypotheses: about the negative impact of economic and financial sanctions on the welfare of the poorest people, about the nonlinear relationship between economic growth and income inequality, and about the impact of country characteristics and the duration of sanctions on income distribution. Having applied econometric modelling to panel data, we found that economic and financial sanctions are detrimental to the low-income population and inappropriate for policies aimed at reducing income inequality. Indicators of economic growth can be linked with both an increase and a decrease in economic inequality due to the nonlinear form of their dependence. Regional characteristics of the countries of Africa, North America and South America determine their propensity to a higher level of inequality, as well as the long duration of sanctions. Finally, sanctions are not harming the richest people, as they are able to shift the burden of sanctions on the rest of the population. The research is relevant in practice, as its results can be taken into consideration when developing a sanctions policy to minimize harmful consequences for the civilian population.

The authors of the study analyze various definitions of chronic heart failure (CHF). CHF, having many faces, despite the consensus concerning the paradigm of its pathogenesis, is given different definitions, using both the syndromic and nosological approaches. Most authors share a view of CHF as the final stage (outcome or complication) of many diseases in which there is impairment of ventricular filling or ejection of blood, i.e. as a syndrome, and not an independent nosological form. Nevertheless, at the beginning of the XXI century leading Russian specialists in heart failure presented a reasoned point of view on CHF not only as the final stage of the cardiovascular continuum, complicating the course of a disease of the cardiovascular system, but also as an independent nosological form. This approach, which contradicts the standard rules for the formulation of the final clinical and pathological diagnoses, as well as the agreed positions of the International Statistical Classification of Diseases and Related Health Problems, has been the subject of reasonable criticism. Since the identification of the underlying cause of heart failure is crucial for therapeutic reasons, the only correct view is that of CHF as a syndrome, the detailed description of which in clinical diagnosis is an important intranosological characteristic that allows building the most effective differentiated therapy and accurately determining the prognosis of the disease.

Heart failure with preserved ejection fraction (HFpEF) and obstructive sleep apnea (OSA) frequently co-occur and this comorbidity represents a separate phenotype of HFpEF. While many research attempts are focused on biomarkers of HFpEF, currently, there is a lack of validated biomarkers of HFpEF and OSA. In this study, we aimed to evaluate prognostic significance of several serum cytokines in patients with HFpEF and OSA. The patients with HFpEF and OSA were recruited from the Sleep Apnea Center of Novosibirsk, Russian Federation and followed up for 12 months. The main analyzed outcomes were five-point major adverse cardiovascular events (MACE) and the 6-min walk test (6MWT). The analyzed cytokines were circulating IL-6, IL-10, and VEGF measured at baseline. We recruited 77 male patients with HFpEF and OSA, the data of 71 patients were available for analyses. Patients who developed MACE had four-fold elevated concentrations of serum IL-10. There was no association between baseline cytokine levels and longitudinal changes in 6MWT. Circulating IL-10 levels are positively associated with MACE in men with HFpEF and OSA and thus may be a potential prognostic biomarker in this subgroup of patients. These results should be confirmed in larger studies encompassing both males and females.

The presented results are based on experimental and computational studies aimed at justifying the application of the cavitation-acoustic hypothesis in describing the process of “fine” fragmentation of hot droplets falling into cold water. Such a process plays a crucial role in small-scale steam explosions. Brief descriptions of other possible mechanisms for the fragmentation of liquid-metal droplets under different conditions are provided, with the main focus given to the fragmentation process induced by shock waves generated by pulsed laser irradiation and mechanical impact. Experimental data on pressure impulses resulting from the collapse of vapor bubbles formed upon contact between the coolant (cold water) and the overheated surface are presented. It is demonstrated that the obtained data, along with photographic evidence of the molten fragments, are consistent with the assumption of the development of the fine fragmentation process according to the cavitation-acoustic scenario. Approximate calculations conducted within the acoustic approximation support this hypothesis.

A significant proportion of natural gas (NG) is produced in cold climates, where conditions are relevant to the formation of gas hydrates in raw gas stream. Methanol is often used as an effective inhibitor of hydrate formation. Further conditioning of NG includes dehydration, and the most common process of water vapor removal from NG is absorption. Absorption also provides removal of methanol vapors, which allows it reuse. The membrane method of natural gas dehydration is considered as a promising alternative; however, the study of methanol recovery by the membrane method, simultaneously to the dehydration of NG, has not been carried out previously. In addition, data on methanol vapor transfer in gas separation polymer membranes are almost absent in the literature. This paper evaluates the permeability coefficients of methanol vapors for several polymer materials, which are applied to the production of industrial membranes (PPO, PSf, CA). Mathematical modeling of the membrane process of NG dehydration with simultaneous recovery of methanol was performed. The dependencies of membrane area, methanol recovery and energy consumption for methane recycling and recompression on the process parameters are calculated. Obtained data show that the recovery of methanol during membrane dehydration of NG varies in the range 57–95%. The lowest values of membrane area and specific energy consumption were found for PPO based membrane.

As the size of the components in electronic devices decreases, new approaches and chemical modification schemes are needed to produce nanometer-size features with bottom-up manufacturing. Organic monolayers can be used as effective resists to block the growth of materials on non-growth substrates in area-selective deposition methods. However, choosing the appropriate surface modification requires knowledge of the corresponding chemistry and also a detailed investigation of the behavior of the functionalized surface in realistic deposition schemes. This study aims to investigate the chemistry of boronic acids that can be used to prepare such non-growth areas on elemental semiconductors. 4-Fluorophenylboronic acid is used as a model to investigate the possibility to utilize the Si(100) surface functionalized with this compound as a non-growth substrate in a titanium dioxide (TiO2) deposition scheme based on sequential doses of tetrakis(dimethylamido)titanium and water. A combination of X-ray photoelectron spectroscopy and time-of-flight secondary ion mass spectrometry allows for a better understanding of the process. The resulting surface is shown to be an effective non-growth area to TiO2 deposition when compared to currently used H-terminated silicon surfaces but to exhibit much higher stability in ambient conditions. [ABSTRACT FROM AUTHOR]

Aim. To study the effectiveness of oral alendronate and ibandronate bisphosphonates for the prevention of cardiovascular complications in postmenopausal women with type 2 diabetes mellitus (DM) and osteoporosis during a 12-month prospective observation. Materials and methods. The study included 86 women with osteoporosis, chronic heart failure (CHF) and type 2 diabetes: the 1st group (n=52) included patients who received basic therapy for heart failure; the 2nd group (n=34) included patients who, in addition to the basic therapy of heart failure, were prescribed alendronic and ibandronic acid preparations for the treatment of osteoporosis. In order to identify the possibility of associating the studied factors with the nature of the course of heart failure, the patients were divided according to the results of a one - year follow - up into two subgroups: subgroup A (n=49) - patients with a favorable course of the disease and subgroup B (n=37) - patients with an unfavorable course of pathology. Results and discussion. After 12 months, a significant decrease in the levels of cerebral natriuretic peptide precursor (NT-proBNP), tumor necrosis factor-α, and interleukin-1β was found in the group of women treated with bisphosphonates compared to baseline. Significant associations of NT-proBNP levels (p=0.02) and the studied cytokines (p=0.01) with an unfavorable course of heart failure were revealed. A significant association of bisphosphonate therapy with a favorable course of heart failure (p=0.01) was also revealed. The probability of developing adverse cardiovascular events during the year in the treatment of heart failure with basic therapy drugs with additional therapy of osteoporosis with bisphosphonates is significantly (p=0.0025) lower than the treatment of patients with heart failure with only basic therapy and not taking bisphosphonates for the treatment of osteoporosis. Conclusion. In postmenopausal women with associated cardiovascular pathology (CHF, type 2 diabetes and osteoporosis), prophylactic therapy with oral alendronate and ibandronate oral bisphosphonates is effective, reduces the risk of progression of heart failure, inhibits inflammatory mediators, positively affects the combined endpoints of comorbid cardiovascular pathology.

Aim. To study the role of soluble stimulating growth factor expressed by gene 2 (sST2), at rest and after exercise at the end of six-minute walk distance (6MWD) in predicting the development of adverse cardiovascular events (CVA) in patients with coronary artery disease with chronic heart failure (CHF) for 12 months of prospective observation. Material and methods. We included 35 patients with CHF of ischemic genesis (32 men) with 44 left ventricular ejection fraction [35; 52]% (average age 62 [57; 67] years). The concentration of sST2 in serum wasdetermined by enzyme immunoassay prior to and immediately after completion of 6MWD.Results. After 12 months of prospective observation, patients were divided into 2 groups depending on the CHF genesis. Group 1 (n=15) included patients with an unfavorable CHF course, group 2 (n=20) included patients without adverse CVA. In patients of group 1, the level of sST2 reached 39,68 [32,28; 52,32] ng/ml, which is 26,2% higher than (p=0,007) the similar parameter in patients of group 2 — 29,29 [26,34;33,78] ng/ml. According to the ROC-analysis, the level of sST2 >33,14 ng/ml can be considered as a marker of the development of adverse CVA for 12 months of observations (sensitivity — 73,3%, specificity — 75,0%, area under the ROC curve — 0,77, p=0,002). After 6MWD patients with unfavorable CHF had a tendency (p=0,211) for an increase in sST2 level by 9,3% from 39,68 [32,28; 33,78] ng/ml to 43,75 [36,85; 54,80] ng/ml. In patients with a favorable course of CHF, the level of sST2 did not change, reaching 29,29 [26,34; 33,78] ng/ml and 29,43 [23,79; 34,79] ng/ml after 6MWD. According to the ROC-analysis, it was found that in patients with coronary artery disease and CHF, determining of sST2 concentration in the blood after 6MWD allowed to achieve higher levels of specificity and sensitivity of stratification risk method of adverse CVA — 86,7% and 85,0%, respectively (the area under the ROC curve is 0,86, p

Aim. To study the mechanisms, features of clinical manifestations and predicting of cardiotoxicity resulting from anthracycline chemotherapy.Material and methods. We examined 176 women with breast cancer who received anthracycline antibiotics as part of polychemotherapeutic (PCT) treatment. Patients were divided into 2 groups: with the development of cardiotoxic remodeling — group 1 (n=52) and with preserved heart function — group 2 (n=124). We conducted echocardiographic (EchoCG) tests before the start, during and after anthracycline chemotherapy. In the serum after the termination of PCT treatment, the concentrations of N-terminal prohormone of brain natriuretic peptide (NT-proBNP) and soluble Fas ligand (sFas-L) were determined.Results. Analysis of EchoCG parameters in patients after 12 months of PCT finish, showed a significant difference in the final systolic and end diastolic sizes, as well as a significant decrease in the left ventricular ejection fraction in group 1 compared with those before the start of treatment. A direct correlation was found between the end-systolic and end-diastolic volumes and inverse correlation between left ventricular ejection fraction and the resulting summary dose of doxorubicin. EchoCG changes in women of group 1 after the first course of PCT treatment were recorded in 49% of cases and 11% of cases — in group 2. The concentrations of sFas-L and NT-proBNP after PCT therapy finish in group 1 were significantly higher compared with group 2. Patients with significantly elevated NT-proBNP levels were had a high risk of heart disease developing during 12 months follow-up. A high concentration of NT-proBNP is a predictor of cardiovascular complications, which is more sensitive than EchoCG.Conclusion. Fas-associated apoptosis plays an important role in the pathogenesis of anthracycline cardiotoxicity. NT-proBNP may be an important biomarker for cardiotoxicity development, which already effective when EchoCG or clinical signs is absent.

A «green» method of obtaining gas separation composite membranes from cellulose solutions and its mixtures with chitosan in orthophosphoric acid is proposed for industrial use, and differs from the viscose method of producing cellophane and other known methods for producing cellulose gas separation membranes without gaseous emissions and wastewater. It is shown that new composite cellulose membranes on a viscose fabric substrate are characterized by high productivity and selectivity for O2/ N2 pairs, comparable to the values obtained for known membranes made of synthetic polymers, as well as increased mechanical strength. The developed composite membranes demonstrate an inverse selectivity for the CH4/CO2 pair, which is not typical for gas separation membranes described in the literature with cellulose-based selective layers.