bluuebunny/crossref_metadata_2025 huggingface dataset:
Dynamics of the Expression of Bone Homeostasis Genes in the Developmet of Aseptic Necrosis of the Femoral Head in the Experiment
Authors: Shabaldin N. A. , Sinitskaya A. V. , Shabaldin A. V. , Mukhamadiyarov R. A.
Published: April 2024

The pathogenesis of a number of diseases is characterized by a violation of the regulation of bone homeostasis, with the progressive development of osteodestruction. At the same time, an active study of the mechanisms leading to a shift in the balance of osteoreparative and osteoresorption directions of osteogenesis is underway. The determination of molecular and cellular patterns affecting the dynamics of changes in bone metabolism is a significant task among a wide range of specialists. Such research works allow us to propose algorithms for targeted therapeutic effects on various key links in the pathogenesis of osteodestruction. The study analyzed the expression of genes involved in maintaining bone homeostasis, changes in the histological picture under experimental conditions, depending on the time elapsed since the induction of aseptic necrosis. The result of the work showed the heterogeneity of the development of osteodestruction in an experiment on Wistar rats, with a surgically created focus of hypoperfusion of the femoral head against the background of increased intra-articular pressure. In the first two weeks of the development of aseptic necrosis, the expression of the hif1a gene was most actively determined, which can be considered from the position of a trigger for further disruption of bone metabolism. At the same time, the concentration of m-RNA of osteogenesis and osteoresorption genes was reduced. The most active osteolytic processes according to electron microscopy data, increases in the expression of osteoclastogenesis induction genes were observed at 6 weeks of the experiment. The osteoreporative orientation of bone metabolism gradually increased from the beginning of the study and 2 months after the manifestation of avascular necrosis of the femoral head, active osteoblasts, increased expression of bone matrix genes, osteoblastogenesis were determined. Thus, the development of osteodestruction is an extremely heterogeneous process, with dynamically changing molecular patterns depending on time, determining the activity of signaling pathways of bone metabolism.
Correction of Immunological and Behavioral Parameters of Rats with Experimental Traumatic Brain Injury with a Preparation of Monoclonal Antibodies to the C3 Component of Complement
Authors: Serebryanaya N. B. , Fomicheva E. E. , Shanin S. N. , Filatenkova T. A. , Zhakhov A. V. , Nekrasova K. A. , Ishchenko A. M.
Published: April 2024

After traumatic brain injury (TBI), inflammation develops in the CNS, an active participant in which is the complement system. Activated complement fragments initiate inflammation, and subsequently significantly affect the processes of repair and regeneration. The aim of the work is to reduce neuroimmune disorders after experimental TBI by blocking excessive inflammation in the early stages of traumatic disease with monoclonal antibodies to the C3 component of complement. The work was carried out on 65 male Wistar rats using the “falling weight” model. To correct neuroinflammation, a preparation of a recombinant monoclonal antibody 3A8, specific for the C3 neodeterminant of the rat complement component, blocking the activation of the alternative complement pathway was administered (i.v., 100 mg/kg). As a reference drug, a recombinant human interleukin-1 receptor antagonist (rIL-1RA) was used, which was administered s.c. (dose of 50 mg/kg). Both drugs were administered once after 30 min of TBI (mode 1) or 24 hours after TBI (mode 2). We studied the levels of corticosterone in the blood, the cytotoxic and proliferative activity of lymphocytes, and behavioral responses in the “plus maze” test. The obtained data indicate that on the 7th day after TBI in rats treated with 3A8 antibodies in mode 1, post-traumatic weight loss was decreased, the natural cytotoxicity of splenocytes and their proliferative activity were increased, and motor and exploratory activity were increased with a significant decrease in the level of anxiety. The introduction of rIL-1RA in these regimens, as well as the combined use of both drugs, did not have a significant effect on the studied parameters.
Recovery of the Functional Activity of KATP-Channels of Pial Arteries after Ischemia/Reperfusion Using Cell Therapy
Authors: Sokolova I. B. , Gorshkova O. P.
Published: April 2024

This study aims to examine the efficiency of intravenous transplantation of human mesenchymal stem cells (hMSCs) performed 7 days after cerebral ischemia/reperfusion (I/R) for recovery of the functional activity of KATP-channels of cerebral arteries. Using a device for intravital visualization of pial vessels, the reaction of arteries to the KATP-channel blocker glibenclamide (GB), the activator of the same channels of pinacidil (PI), acetylcholine (ACh), and ACh against a background of GB action (ACh/GB) 14 and 21 days after I/R and intravenous hMSC transplantation performed 7 days after ischemic exposure. On exposure to GB 14 days after I/R, 1.5–1.8 times fewer arteries narrowed than in the sham–operated (SO) rats. By day 21 after I/R, the constriction reaction was completely restored, except for arteries with a diameter more 40 μm. In the cell–therapy group, the constrictor response to GB was completely recovered to the level of SO animals in arteries with a diameter less than 40 μm by 14 day after I/R exposure; in arteries with a diameter of more than 40 μm, the constriction reaction did not recover until 21 days. The number of dilations per ACh/GB compared to a clear ACh in SO rats was reduced in 1.6–1.8 times on 14 day after I/R and in 1.6–6.6 after 21 days. In I/R animals on 14 day, the number of dilatations per ACh/GB compared to clear ACh was significantly increased in arteries with a diameter of more than 20 μm by 1.5–1.7 times, and after 21 days in arteries with a diameter of more than 40 μm by 1.2 times. After the introduction of hMSC, GB blocked ACh–mediated dilation in arteries less than 40 μm in diameter both on days 14 and 21 after I/R. In arteries with a diameter of more than 40 μm the functional activity of KATP-channels did not recover until 21 days. Conclusion. I/R of the rat cerebral cortex reduces the contribution of KATP-channels to maintaining the basal tone of the pial arteries and almost completely excludes these channels from the formation of ACh–mediated dilation during 21 days of the postischemic period. Practically did not participate in the dilatory response. Intravenous transplantation of hMSC, performed 7 days after I/R, results in restoration of participation of SMC KATP-channels in maintaining the basal tone and ACh–mediated dilatation of pial arteries with a diameter less than 40 μm already 14 days after I/R.
Comparative Analysis of the Fibrosis Factors Expression in the Heart Tissue of Sprague-Dawley and Wistar Rats during Development of Chronic Renal Failure
Authors: Agalakova N. I. , Mikhailova E. V. , Piankov А. А. , Nadei O. V. , Ershov I. А. , Galagudza M. V. , Bagrov A. Y. , Romanova I. V.
Published: April 2024

The severity of the development of uremic cardiomyopathy (UC) and fibrosis of cardiac tissue at chronic renal failure (CRF) was compared in the model experiments on male Sprague-Dawley and Wistar rats of the SPF category. To induce CRF in rats, subtotal nephrectomy (NE) was performed on the left, and after 2 weeks, total nephrectomy on the right. Sham-operated (Sham) animals served as controls. 4 weeks after the second surgery, blood pressure (BP) was measured in animals, and the expression of fibrotic factors (transcription factor Fli1, pro-collagen-I, collagen-I and collagen-IV) in the tissues of heart left ventricle was evaluated by real-time PCR and immunoblotting. After NE, Sprague-Dawley rats exhibited a significant increase in systolic blood pressure and left ventricular hypertrophy. In Wistar rats, the difference in BP between NE and Sham animals was smaller, and the ratio of left ventricular mass to body weight did not change. Experimental CRF in Sprague-Dawley rats was accompanied by a 1.5–2.5-fold suppression of the Fli1 gene expression and a decrease in the content of Fli1 protein in the cardiac tissue, while no significant differences were observed in Wistar rats. The levels of pro-collagen-I and collagen-I in the heart of rats of both lines did not change either at the levels of transcription or translation. Such difference in development of pathological processes indicates ineffectiveness of applied NE scheme for induction of UC and investigation of pro-fibrotic processes in Wistar rats.
Electric Epidural Stimulation of the Spinal Cord of the Decerebrated Rat
Authors: Shkorbatova P. Yu. , Lyakhovetskii V. A. , Gorsky O. V. , Pavlovaa N. V. , Bazhenova E. Yu. , Kalinina D. S. , Musienko P. E. , Merkulyevaa N. S.
Published: April 2024

Decerebrated animals are often used in experimental neurophysiology to study multilevel physiological processes. The model of a decerebrated cat is traditionally used to study locomotion in acute experiments. We wondered if it would be possible to replace it with electrical epidural stimulation of the spinal cord with a decerebrated rat model. On an acute preparation of 16 Wistar rats decerebrated at the precollicular level, the tonic muscles activity, muscles evoked potentials and the possibility of inducing locomotion during electrical epidural stimulation of the spinal cord, were studied. Histological control of the level of decerebration was performed in 10 rats. Quadrupedal walking was induced in five animals, bipedal hindlimb walking – in one animal; the parameters of the evoked locomotion do not depend on the substantia nigra degree of damage. The tonic activity and the amplitude of the sensory component of the evoked potential of the hindlimb muscles (mm. tibialis anterior and gastrocnemius medialis) depend on the rostrocaudal level of decerebration – they are higher when the substantia nigra is damaged. Thus, the model under consideration makes it possible to successfully study muscle tonic activity and evoked muscle potentials; however, the use of this model in the study of controlled locomotion requires additional research.
Studying the Involvement of Ghrelin in the Mechanism of Gambling Addiction in Rats after Exposure to Psychogenic Stressors in Early Ontogenesis
Authors: Lebedev A. A. , Purveev S. S. , Sexte E. A. , Reichardt B. A. , Bychkov E. R. , Shabanov P. D.
Published: April 2024

We investigated the role of ghrelin and its receptors in the manifestation of gambling a-ddiction elements in rats exposed to early psychogenic stress. Rearing in conditions of social isolation or maternal deprivation in early ontogeny increased risk behavior and impulsivity in the Iowa Gambling Task test: animals sought more food reinforcement, but with a low probability. Maternal deprivation or rearing in social isolation increased expression of Ghsr in the amygdala and hypothalamus respectively. The level of expression of the gene under study in the prefrontal cortex did not change. It is concluded that early psychogenic stress causes an imbalance in the brain ghrelin regulatory system, which manifests itself in increased of Ghsr level as well as elements of gambling addiction. The scheme of the effect of chronic stress on the hypothalamic ghrelin system and on the extrahypothalamic regulation of ghrelin is presented.
Dose-Response of the Mitomycin C Genotoxic Effect on the ApoE Knockout Mice
Authors: Asanov M. A. , Shishkova D. K. , Poddubnyak A. O. , Sinitsky M. Y. , Sinitskaya A. V. , Khutornaya M. V. , Ponasenko A. V.
Published: April 2024

Polychromic erythrocytes have been accepted as a suitable target for micronucleus (MN) evaluation in both acute and cumulative injury. Mitomycin C (MMC) also has a wide range of genotoxicity, including inhibition of DNA synthesis, clastogenesis and mutagenesis. As an immediate clastogen requiring exclusively intracellular reductive activation, MMS initiates efficient DNA crosslinking. The in vivo micronucleus assay has established itself as a standard assay for evaluating chromosomal genotoxicity in mouse erythrocytes. Most of the studies are focused on the study of acute acute effects, which is caused by high doses of the mutagen. In turn, there are no or very few studies aimed at studying the chronic effects of MMS. The aim of the study is to create a chronic genotoxic effect of MMS without lethal outcome in ApoE–/– mice when selecting the optimal dose of MMS. The design of the study included 6 groups of ApoE–/– mice, two doses of MMC at a concentration of 0.1 and 0.5 mg/kg, single and three doses. Each group consisted of four females and one male. To assess genotoxicity, 1000 polychromic erythrocytes (PChE) extracted from the femoral bone marrow were counted on each sample, PChE with micronuclei were detected, and the proportion of reticulocytes was counted. A dose of 0.5 mg/kg showed a clear cytotoxic effect, expressed in a violation of erythropoiesis, and more precisely in a decrease in the proportion of reticulocytes. In our study, the concentration of the mutagen, namely 0.1 mg/kg, was shown to cause a clear genotoxic effect without reaching the threshold of cytotoxicity. Dose-response studies in rodents can provide useful information on the mechanisms of toxicity and dose selection for long-term toxicity studies.
Methods of Closed-Loop Adaptive Neurostimulation: Features, Achievements and Prospects for Development
Authors: Fedotchev A. I.
Published: April 2024

An innovative approach to the organization of stimulation procedures is analyzed – closed-loop adaptive neurostimulation, in which the parameters of sensory stimulation are automatically controlled by feedback signals from the person’s own physiological characteristics. The effects of using invasive and non-invasive magnetic and electrical brain stimulation, as well as the effects of closed-loop acoustic and audiovisual stimulation, controlled by human rhythmic processes are considered. Numerous examples demonstrate the features and achievements of a new approach in the treatment of various psychosomatic disorders and cognitive rehabilitation of a person. The prospects for development of this research area are outlined. The results of the author’s own research in this direction are presented.
Effect of Heparin on the Formation and Healing of Gastric Ulcers Induced by Acetic Acid Application on the Gastric Mucosa in Rats
Authors: Efimov A. L. , Sakhno D. S. , Sigua B. V. , Yarushkina N. I. , Filaretova L. P.
Published: April 2024

The key factor in maintaining the integrity of the gastric mucosa is its normal blood supply, respectively, the use of drugs that improve it, including through a positive effect on the rheological properties of blood, is in demand for the treatment of gastric ulcer. These drugs include the anticoagulant heparin. The aim of the work is to study the effect of heparin on the formation and healing of gastric ulcers induced by the application of 60% acetic acid to the gastric mucosa in rats, while assessing the possible risk of bleeding. After application of acetic acid (day 0), the area of gastric ulcers was assessed on the 4th day (formation of the ulcers) and the 7th day (healing of the ulcers). To assess the effect on ulcer formation, heparin (1000 IU/kg/day, subcutaneously) was administered from days 0 to 3, and on the healing from days 4 to 6 after acid application. To check for possible bleeding under the influence of heparin, the level of hemoglobin in the blood was tested before acid application (basal), on the 4th and 7th days after application. The degree of bleeding was assessed based on the relative decrease in hemoglobin levels. The administration of heparin led to a decrease in the average area of ulcers both on the 4th and on the 7th day compared with that in control rats (heparin vehicle). In control rats, both on the 4th and on the 7th day, the hemoglobin level was reduced compared to the corresponding basal level. Heparin had no effect on the hemoglobin level at day 4, but potentiated the decrease in mean hemoglobin level at day 7, increasing the number of animals having a greater relative decrease in hemoglobin level compared to the corresponding control group. Thus, heparin may have a gastroprotective effect, manifested both in the weakening of the formation of an ulcer and in the acceleration of its healing, however, there is a risk of bleeding when the ulcer heals.
The Role of Variability in Monoamine Transporter Genes in Sports Physiology
Authors: Cherepanova A. V. , Bravy Y. R. , Karabelsky A. V. , Kotova M. M. , Kolesnikova T. O. , Kalueff A.V.
Published: April 2024

Monoamine transporters (MATs) are responsible for the reuptake of dopamine, serotonin, and noradrenaline, modulating the concentration of these essential brain neurotransmitters and thus regulating behavior, mood, and cognitive functions. The study of the role of various genes in complex physiological processes is a promising area of neurobiology and sport physiology. Here, we summarize mounting evidence linking specific genetic variants of MAT genes to various aspects of sport performance. For example, the allele 10 of the dopamine transporter gene (DAT), the allele L of the serotonin transporter gene (SERT) and single-nucleotide polymorphism rs1805065 (Thr99Ile) of the noradrenaline transporter gene (NET) appear to correlate with higher performance in athletes due to resistance to stress, maintenance of motivation and cognitive behavioral competencies – qualities necessary for achieving success in sport. Thus, physiological performance in various sports may be partially genetically determined and controlled by the MAT genes.
Endothelium-Independent Anti-Contractile Effect of Rat Aorta Perivascular Adipose Tissue at Control and Metabolic Disorders Induced by the Cafe Diet
Authors: Pankova M. N.
Published: April 2024

The use of high-calorie nutrition can lead to morpho-functional changes of the vascular bed that have clinical importance, however, the modulatory effect of perivascular adipose tissue (PVAT) on the vascular system in this process remains poorly characterized. The aim of this work was to study the direct effect of PVAT on the contractile activity of rat aortic smooth muscle in metabolic disorders that occur when using the cafe diet (CD). It was shown that 7 weeks of keeping animals on this diet led to excessive accumulation of visceral adipose tissue, disorders of carbohydrate and lipid metabolism, manifested in the form of hyperglycemia and hypertriglyceridemia, which characterizes the development of the metabolic syndrome. An important functional role of PVAT in the regulation of vascular tone was demonstrated using wire myography on annular without endothelium segments of the thoracic aorta of the rat. In the control group of animals on a standard diet, the presence of PVAT reduced vasoconstriction caused by stimulation by phenylephrine. In the experimental group, in rats with the metabolic syndrome caused by DC, there was a decrease in the protective effect of PVAT. The implementation of this effect was carried out with the participation of voltage-dependent and/or Ca2+-activated K+-channels of smooth muscles, while the involvement of ATP-sensitive K+-channels was weak and independent from metabolic changes caused by the use of CD. Part of the anticontractile effect of PVAT was mediated through nitric oxide (NO) produced by PVAT itself. Under metabolic changes caused by CD, the endothelium-independent anticontractile effect of NO is completely eliminated without changing the sensitivity of vascular smooth muscles to it.
The Role of Reactive Oxygen Species in the Regulation of Blood Vessel Tone in Perinatal and Early Postnatal Ontogenesis
Authors: Shvetsova A. A. , Gaynullina D. K. , Tarasova O. S.
Published: April 2024

Reactive oxygen species (ROS) have been considered for many years as negative regulators in the cardiovascular system. Indeed, excessive production of ROS characterizes many cardiovascular diseases. The damaging effect of ROS can be especially pronounced in a newborn organism, since during this period their contractile effect in pulmonary arteries remains as high as in the pre-term fetus arteries and the antioxidant systems have not yet formed. Therefore, in the first hours and days of independent life, pulmonary arteries tend to contract, primarily due to the low bioavailability of endothelial NO, which increases the risk of developing pulmonary hypertension in newborns. At the same time, during the perinatal period, ROS play an important role in the adaptive reactions of the circulatory system. ROS provide occlusion of the ductus arteriosus and separation of the pulmonary and systemic circulations soon after birth, and also contribute to the contraction of peripheral vessels during hypoxia, which often accompanies the delivery, and therefore provide priority blood supply to the brain in these conditions. The vasomotor effect of ROS is also pronounced in early postnatal ontogenesis, but it has a different character. In the first weeks of life, the action of ROS serves as one of the mechanisms for increasing endothelium-dependent relaxation of pulmonary vessels. In addition, during early postnatal ontogeny, ROS may play an important role in the regulation of systemic vascular tone. This review outlines the current understanding of the vasomotor role of ROS in the vessels of the pulmonary and systemic circulation and considers the mechanisms of ROS effects on the functioning of vascular endothelial and smooth muscle cells in the perinatal and early postnatal periods.
Expression of Apoptosis and Autophagy Genes in HeLa and HEK 293 Cells under Conditions of Nutrient Deprivation
Authors: Trubnikova A. D. , Prokopenko E. S. , Sokolova T. V. , Nadei O. V. , Agalakova N. I.
Published: April 2024

The goal of the study was a comparing the degree of development of autophagy in the human cervical carcinoma cells of HeLa-V and HeLa-R sublines and non-tumor human embryonic kidney cells HEK 293 under two types of starvation conditions – 24- and 48-h culture in serum-free DMEM medium and 4-h incubation in Earle’s minimal medium. The work assessed cell viability using MTT method and the expression of apoptosis (BCL2, BAX, CASP3) and autophagy (ULK1, BECN1, ATG5, ATG14, MAP1LC3B) genes using real-time PCR. Cultivation under serum starvation and Earl’s medium resulted in a significant decrease in the viability of HEK 293 cells, but had no influence on HeLa-V and HeLa-R cells. In the tumor cells of both lines, the expression of anti-apoptotic gene BCL2 increased, while in HEK 293 cells the BCL2/BAX ratio decreased and CASP3 gene was activated. In HeLa-V and HeLa-R cells, nutrient deprivation induced the stimulation of various combinations of genes ULK1, BECN1, ATG5 and ATG14 implicated in the initial stages of autophagy, but none of the treatments affected the expression of MAP1LC3B gene. In HEK 293 cells, serum starvation led to increase in expression level of BECN1, ATG5, ATG14 and MAP1LC3B genes. Thus, stimulation of autophagy in HeLa cells, especially HeLa-R, prevents the development of apoptotic processes, while in HEK 293 cells the processes of apoptosis and autophagy occur in parallel. Culture in the serum-free DMEM for 48 h appears to be most effective way to induce autophagy in tumor cell lines and, accordingly, the most suitable model for studying the role of autophagy in the development of their resistance to apoptotic pathway of death.
Steam Conversion of Ethane and Methane–Ethane Mixtures in Membrane Reactor with a Foil from Pd–Ru Alloy
Authors: Didenko L. P. , Babak V. N. , Sementsova L. A. , Dorofeeva T. V. , Chizhov P. E. , Gorbunov S. V.
Published: April 2024

The features of steam conversion of ethane and methane-ethane mixtures containing 5, 10 and 15% ethane in a membrane reactor with a 30 μm thick Pd–Ru foil at temperatures of 1800 and 3600 h–1 and steam/feed rations of 3 and 5 have been investigated. Comparative experiments with “non-membrane” reaction have shown that in the membrane reactor the feedstock conversion to form H2 and CO2 increases and ethane hydrocracking decreases. Increasing the rate of H2 recovery through the membrane by permeate evacuation leads to an increase in the yield of H2 and CO2. With a decrease in the steam/feed ratio from 5 to 3, the ethane hydrocracking and the rate of carbon deposits formation increases. Optimal conditions for steam conversion of ethane and methane-ethane mixtures are T = 773 K, feed space velocity of 1800 h–1 and steam/feed ratio of 5. The established regularities are similar to those obtained earlier for other types of raw materials (mixtures of methane with propane, propane, n-butane, a mixture simulating the average composition of associated petroleum gas) in this membrane reactor.
Properties of Polysulphones Synthetized for Forming of Porous Hollow-Fiber Membranes
Authors: Borisov I. L. , Matveev D. N. , Anokhina T. S. , Shakhmurzova K. T. , Zhansitov A. A. , Slonov A. L. , Kurdanova Zh. I. , Khashirova S. Yu. , Volkov V. V.
Published: April 2024

For the first time, for the problem of hollow fiber membranes spinning, polysulfones in a wide range of molecular weights (42 000–184 000 g/mol) were synthesized in such aprotic dipolar solvents as dimethylacetamide, N-methyl-2-pyrollidone, and dimethyl sulfoxide. The dependence of the thermal and mechanical properties of polysulfones on molecular weight characteristics has been studied. A comparison of the mechanical properties of the synthesized PSF, commercial PSF Ultrason S 6010 (BASF, Germany) and PSF-150 (JSC Institute of Plastics, Russia) showed that the synthesized polymers are not inferior to commercial analogues. Some synthesized polymers surpass commercial PSF in terms of elasticity and strength modulus. Based on the study of the spinning solutions dynamic viscosity, promising PSF samples were selected for the formation of porous hollow fiber supports. It was found that hollow-fiber porous support from a PSF sample with a molecular weight of 110 000 g/mol have a high nitrogen permeability of 47.5 m3/m2 · h · bar. Such supports are promising for casting highly permeable composite membranes with a thin selective layer.
Study of the Specific Adsorption of Calcium Ions on the Surface of Heterogeneous and Homogeneous Cation-Exchange Membranes to Increase Their Selectivity towards Singly Charged Ions
Authors: Gil V. V. , Ruleva V. D. , Porozhnyy M. V. , Sharafan M. V.
Published: April 2024

Ion-exchange membranes with high specific selectivity towards singly charged ions are in demand in various industries. One of the ways to increase the specific selectivity can be formation of a thin layer on the membrane surface with a charge opposite to the charge of its fixed groups. The possibility of forming such a layer due to the specific interaction of calcium ions with the sulfonate groups of the membrane during treatment with a high-intensity electric current in a CaCl2 solution is studied. The ability of heterogeneous (MK-40, Ralex CMH) and homogeneous (CMX, CJMC-5) sulfocationite membranes for specific adsorption of calcium ions on their surface is investigated. It is shown that the CMX membrane exhibits this ability to the greatest extent, which is due to the higher density of \( - {\text{SO}}_{3}^{ - }\) groups on its surface compared to other studied membranes. It is found that the formation of a thin positively charged layer on the surface of the CMX membrane increases the permselectivity coefficient of the membrane, \({{P}_{{{{{\text{N}}{{{\text{a}}}^{{\text{ + }}}}} \mathord{\left/
{\vphantom {{{\text{N}}{{{\text{a}}}^{{\text{ + }}}}} {{\text{C}}{{{\text{a}}}^{{{\text{2 + }}}}}}}} \right.} {{\text{C}}{{{\text{a}}}^{{{\text{2 + }}}}}}}}}},\) by 69%. At the same time, the presence of such a layer does not lead to an increase in undesirable water splitting, which occurs when applying widely used as modifiers polyelectrolytes with amino groups.
Poly(1-trimethylsilyl-1-propyne) of a cis-Rich Configuration — a Membrane Material for the Separation of Butane/Methane Mixtures as Natural Gas Components
Authors: Makrushin V. P. , Kossov A. A. , Levin I. S. , Bezgin D. A. , Syrtsova D. A. , Matson S. M.
Published: April 2024

In this work, for the first time, we studied the permeability of individual lower hydrocarbons and in a C1/C4 mixture for films based on PTMSP of a new cis-enriched configurational composition (the content of cis-units in the samples was 80 and 90%). The methane permeability of freshly prepared cis-regular PTMSP films (90% of cis-units) exposed to air for a month is higher than the corresponding values of PTMSP films with 80% cis-units. The X-ray diffraction data indicate a looser packing of the cis-regular PTMSP. The introduction of the antioxidant Irganox 1076 into PTMSP films leads to a decrease in the initial level of the methane flux. At the same time, the permeability of films with the addition of Irganox 1076 over time (within 1 month) decreases much more slowly compared to films without the addition of an antioxidant. The permeability of individual lower hydrocarbons through PTMSP films without and with the addition of Irganox 1076 increases in the order С1 C2 C3 C4. The value of the separation factor in the n-butane/methane mixture reaches 33, which is almost 7 times higher than the selectivity for individual components. The high level of n‑butane permeability of cis-enriched PTMSP is maintained for at least a month of films storage in air.
State-of-the-Art of Forward Osmosis Technology: Prospects and Limitations
Authors: Andrianov A. P. , Yantsen O. V. , Efremov R. V.
Published: April 2024

Forward osmosis is considered as an emerging technology that can compete with existing methods of desalination, purification and concentration of natural and wastewater on the global water market. This review presents possible applications of forward osmosis, technological schemes and the most striking case studies. The issues of forward osmosis membranes development and improvement, composition and regeneration of draw solutions, membrane fouling are considered. Special attention is paid to the problems arising during forward osmosis operation, to energy and economic assessment of new technology. Conclusions are drawn about the status of the commercial implementation of forward osmosis and the main barriers that stand in the way of its development.
Electrodialysis Separation and Selective Concentration of Sulfuric Acid and Nickel Sulfate Mixed Solution Using Membranes Modified by Polyaniline
Authors: Loza S. A. , Romanyuk N. A. , Falina I. V. , Loza N. V.
Published: April 2024

The paper discusses the electrodialysis treatment of mixed nickel sulfate and sulfuric acid solution using polyaniline surface-modified cation exchange membranes. The modified membranes are obtained on the basis of industrial cation-exchange MK-40 heterogeneous and MF-4SK homogeneous membranes by in situ oxidative polymerization of aniline under electrodialysis conditions. The conductive and diffusion characteristics of the initial and modified membranes in solutions of sulfuric acid and nickel sulfate are studied. It is shown that the modification of membranes with polyaniline leads to a decrease in their electrical conductivity and diffusion permeability while maintaining high selectivity. The diffusion permeability of cation-exchange membranes is higher in nickel sulfate solutions compared to sulfuric acid one, while an inverse dependence is found for anion-exchange membranes. The competitive transfer of sulfuric acid and nickel sulfate during electrodialysis separation and concentration of their mixture using initial and modified cation-exchange membranes paired with anion-exchange MA-41 membrane are studied. It is shown that the applying a polyaniline layer with positively charged groups on the surface of the MK-40 or MF-4SK cation-exchange membranes suppresses the transport of doubly charged nickel ions both in the separation and concentration modes over the entire range of current densities. The greatest repulsion effect is observed for homogeneous modified membranes, where the selective permeability coefficient P(H2SO4/NiSO4) increases from 0.7–1.7 to 32.5–19.7 depending on the current density. It is established that the use of polyaniline modified cation-exchange membranes permits to concentrate the solution containing 0.1 mol-eq/L (4.9 g/L) H2SO4 and 0.1 mol-eq/L (7.7 g/L) NiSO4, with simultaneous separation into sulfuric acid with concentration about 2.4 mol-eq/L (120 g/L) and nickel sulfate solutions. The content of nickel sulfate in the concentrate does not exceed 0.13 mol-eq/L (10 g/L).
New Hybrid Membrane Based on Poly(m-Phenylene-iso-Phthalamide) for Pervaporation of Methanol/n-Heptane Azeotropic Mixture
Authors: Pulyalina A. Yu. , Faykov I. I. , Sorokina A. S. , Tian N. S. , Kuryndin I. S. , Polotskaya G. A.
Published: April 2024

The object of this work is a new hybrid membrane based on poly(m-phenylene-iso-phthalamide) (PA) modified with a complex filler consisting of equal amounts of heteroarms star macromolecules (HSM) and [BMIM+Tf2N–] ionic liquid (IL). Comparative studies of the structure were carried out on samples of membranes made of pristine PA and hybrid PA/HSM and PA/(HSM:IL) containing 5 wt % additives; methods of AFM, X-ray phase analysis, measurement of density and contact angles were used. The transport properties of membranes were studied in separation of a methanol/n-heptane mixture by the pervaporation method. The actuality of this problem is associated with the process of oil refining. In pervaporation of an azeotropic methanol/n-heptane mixture, the hybrid PA/(HSM:IL) membrane demonstrated higher performance and separation factor relative to reference membranes. Mechanical tests of the membranes revealed a high level of properties important for operation (strength and relative elongation) of the hybrid membrane.
Counterion Transference Numbers in the Cell Model of a Charged Membrane
Authors: Filippov A. N.
Published: April 2024

The paper suggests exact formulae for calculating the electromigration, diffusion and convective numbers of counterion transport in the cell model of a charged membrane depending on the physicochemical parameters and the equilibrium concentration of the electrolyte. The cell model was previously developed to calculate all the kinetic coefficients of the Onsager matrix and the asymmetry of the cross coefficients was established. The limiting case of an ideally selective membrane is studied in detail, for which approximate formulae for transference numbers are obtained. The obtained dependences are illustrated by graphs using the example of the MK-40 cation-exchange membrane after conditioning at room temperature. The proposed method for calculating the transference numbers is applicable to any single-layer membranes in binary electrolyte solutions.
Neutralization Dialysis of Phenylalanine and Mineral Salt Mixed Solution: Effect of Concentration and Flow Rate of Acid and Alkali Solutions
Authors: Porozhnyy M. V. , Gil V. V. , Kozmai A. E.
Published: April 2024

Amino acids that are ampholytes can be effectively separated and purified by the method of neutralization dialysis (ND), whose advantage is the ability to control the pH value of the solution without adding reagents. An important task is to optimize the parameters of the ND process to ensure minimal losses of amino acids during their isolation from mixed solutions. An experimental study of the process of demineralization of the phenylalanine and sodium chloride equimolar mixture by the ND method was carried out. It is established that varying the concentration and flow rate of acid and alkali solutions in the corresponding compartments of the dialysis cell allows for regulating the pH value of the solution being desalted and controlling the amount of amino acid loss. Halving the acid concentration (from 0.10 to 0.05 M) allowed reducing the losses of phenylalanine from 18.3 to 16.4%, and using a lower solution flow rate in the acid compartment (0.75 instead of 1.50 cm s–1) made it possible to reduce these losses to 14.2%. At the same time, in all experiments, the electrical conductivity of the desalted solution decreased by 90%, which suggests a high degree of demineralization and the effectiveness of the method used to isolate phenylalanine from the mixed solution.
Gas Transport Properties of Vinylidene Fluoride-Tetrafluoroethylene Copolymers
Authors: Alentiev A. Yu. , Nikiforov R. Yu. , Levin I. S. , Tsarev D. A. , Ryzhikh V. E. , Syrtsova D. A. , Belov N. A.
Published: April 2024

The influence of the content of tetrafluoroethylene (TFE) groups on the gas transport properties of vinylidene fluoride (VDF) and tetrafluoroethylene copolymers has been studied. Experimental values of the permeability coefficients P and diffusion coefficients D for gases H2, He, N2, O2, CO2, as well as lower hydrocarbons CH4, C2H4 and C2H6 were measured and their solubility coefficients S were calculated. The values of the solubility coefficients of CO2 and C2H4 were found to deviate from the linear correlation of lg S on the Lennard-Jones potential. An explanation of this effect was proposed based on facilitated transport models. It was demonstrated that an increase in the content of TFE groups leads to a significant increase in the permeability coefficients of the penetrants studied mainly due to an increase in their diffusion coefficients. So, the permeability coefficient of helium and hydrogen increases approximately in 2.5 times, for carbon dioxide in 3 times, for argon, oxygen, methane and ethylene in 3.5 times, and for nitrogen and ethane in 4.4 times, respectively. These gas separation parameters in combination with good film-forming properties and commercial availability allows us to consider the studied VDF-TFE copolymers as promising materials for the fabrication of composite gas separation membranes.
Kinetic Analysis of Dry Reforming of Methane on Traditional and Membrane Catalysts
Authors: Gavrilova N. N. , Gubin S. A. , Myachina M. A. , Sapunov V. N. , Skudin V. V.
Published: April 2024

The article presents an analysis of the results of a kinetic study of dry reforming of methane (UCM) in reactors with traditional (TC) and membrane catalysts (MC). The kinetic experiment in reactors with MC and TC was performed in the temperature range of 820–900°C and the ratio CH4 : CO2 = 1 : 1. In the experiment, an intensification of the process of the methane cracking reaction was established, the rate constant of which increases by an order of magnitude. Such a difference in the results of the DRM on the studied catalysts are due to the intensification of mass transfer on the MC, which is based on the phenomenon of thermal slip. A mathematical description corresponding to the kinetic scheme of DRM process is proposed, and the rates constants of direct and reverse reactions in both reactors are found. In the DRM process, water gas is formed on the TC, and synthesis gas is formed on the MC. At TC, the DRM process is accompanied by the accumulation of carbon deposits (CD), and at MC this accumulation is absent. The DRM process on both catalysts is characterized by three main reactions (methane cracking, gasification of the CD with carbon dioxide and/or water vapor and the reverse water gas shift), which were assumed to be reversible under experimental conditions. It turned out that on TC the gasification of the CD occurs in the reverse reaction of methane cracking, and on the MC—in the reactions of gasification by water vapor (mainly) and carbon dioxide. The process on the MC is characterized by irreversible reactions of methane cracking, gasification of the CD with water vapor and carbon dioxide. The reverse water gas shift reaction on the MC remains reversible, and its rate constants of the direct and inverse reactions turned out to be an order of magnitude lower than similar constants on the TC.
Simulation of the Impurity Absorption from a Laminar Flow in a System of Hollow-Fiber Membranes
Authors: Kirsh V. A.
Published: April 2024

The external stationary flow of a viscous incompressible fluid and the convective-diffusion mass transfer of a solute in an ordered system of parallel hollow fiber membranes arranged normally to the flow direction are calculated in the ranges of Reynolds numbers \(\operatorname{Re} \) = 0.01–100 and Schmidt numbers \({\text{Sc}}\) = 1–1000. The Navier–Stokes equations and the equation of convective diffusion were solved using the methods of computational fluid dynamics with a no-slip boundary condition and with a constant solute concentration condition on the outer surface of the streamlined fiber. The calculations were performed for a row of fibers and for a multi-fiber system consisting of four and sixteen rows of fibers. The outlet concentrations and the fiber solute retention efficiencies \(\eta \) were calculated depending on the packing density of the fibers and the \(\operatorname{Re} \) and \({\text{Sc}}\) numbers. It is shown that it is possible to use the fiber solute retention efficiency \(\eta \) defined for a single row of fibers to predict the retention efficiency of an extended multi-row fibrous bed.
Characterization of Pyrenophora tritici-repentis, Parastagonospora nodorum and Parastagonospora pseudonodorum populations based on the presence of effector genes in the Tambov Oblast territory
Authors: Kovalenko N. M , Zeleneva Yu. V , Sudnikova V. P
Published: April 2024

The aim of the research is to characterise the populations of Pyrenophora tritici-repentis, Parastagonospora nodorum and Parastagonospora pseudonodorum in the territory of the Tambov region based on the presence/absence of the Tox1, Tox3, ToxA and ToxB effector genes using their associated molecular markers. Infectious samples were obtained in 2022 from the leaves of spring and winter wheat. The infectious site is located in the northeastern part of the Central Black Soil region. The predecessor is represented by the pure steam. The species of P. nodorum and P. pseudonodorum were observed on spring wheat cultivars in the end of their vegetation period. The fungus of P. tritici-repentis affected the cultivars of both winter and spring wheat. Using molecular markers, the genes encoding NEs were identified in 68 P. tritici-repentis isolates obtained from 19 winter wheat cultivars, 100 P. nodorum isolates, taken from 10 spring wheat cultivars, and 70 P. pseudonodorum isolates, provided by 7 spring wheat cultivars. Among the P. nodorum isolates studied, there were both single genes Tox1, Tox3, and ToxA, as well as combinations of two genes in one genotype. The presence of the ToxA gene was not found in the genotype of P. pseudonodorum isolates. Fungal isolates with genotypes carrying Tox1 and/or Tox3 have been identified. The ToxB gene was not found in the examined population of P. tritici-repentis, while ToxA was widely represented. The occurrence of genes in the P. nodorum population was as follows: ToxA, 30%; Tox1, 20%; Tox3, 30%; in the population of P. pseudonodorum it was: Tox1 - 57.1%, Tox3 - 30 %; in the population of P. tritici-repentis the ratio was represented by the following figures: ToxA - 76.5%. P. tritici-repentis, P. nodorum, and P. pseudonodorum strains, characterized by the presence of effector genes, will be used to create artificial infectious backgrounds to identify sources and donors of leaf spot resistance.
Variety features and methods of increasing the productivity of white mustard
Authors: Prakhova T. Ya , Taishev N. R
Published: April 2024

The aim of the research was to study the e ect of pre-sowing and foliar treatment with microelement micronutrient fertilizers on the productivity of white mustard and a comparative assessment of its varieties in the conditions of the forest- steppe of the Middle Volga region.Experimental work was carried out in 2020-2022 on the experimental eld of the Penza Research Institute of Agriculture. In the rst experiment, 9 varieties of white mustard of various selection, included in the State Register of Breeding Achievements, were studied. The scheme of eld experiments included the study of pre-sowing seed treatment and the treatment of mustard plants during vegetation with microfertilizers at a rate of 1.0 l/t and 1.0 l/ha, respectively. The experimental scheme included 8 microelement preparations (Humate +7, Agroverm, Izagri Vita, Megamix, Zircon, Cytovit, BlackJack, Izagri Force) and a variant without treatment. On average, over three years, the productivity of mustard seeds varied within 1.32-1.61 t/ha, depending on the variety. The highest yield in the experiment was noted in the varieties Lutsiya (1.57 t/ha) and Svetlanka (1.61 t/ha), which exceeded the average value for the experiment by 0.10…0.14 t/ha. The maximum oil content in the experiment was noted in the varieties Lucia and Omega (30.02 and 30.48 %), the minimum - in the varieties Passion and Bracco (25.05 and 26.24 %). At the same time, all varieties had a high indicator of agronomic stability at the level of 78.33 … 85.82 %, which characterizes their value for production. As a result of the use of microfertilizers, a tendency to increase the productivity of mustard was noted. When foliar processing of mustard plants, the most e ective fertilizers were Izagri Vita and Agroverm, which contributed to obtaining the largest yield of 1.69 and 1.67 t/ha. The maximum oil content in the experiment (29.72 and 29.70 %) was noted in the seeds when the plants were treated with BlackJack and Isagri Force preparations. Pre-sowing treatment of seeds with microelement fertilizers contributed to the accumulation of oil in the seeds up to 27.75-29.46 %, with 27.87 % in the control. The highest yield in the experiment was obtained in the variants with seed treatment with Izagri Vita and BlackJack preparations (1.71 and 1.72 t/ha), which exceeded the control by 0.17…0.18 t/ha. In addition, the studied preparations a ect the fatty acid composition of oilseeds to varying degrees. Their application led to a decrease or increase in the concentration of fatty acids. Foliar top dressing with Cytovit contributed to an increase in the concentration of erucic acid up to 30.1 %. And pre-sowing treatment of seeds with this preparation leads to its decrease to 25.3 %.