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The specifics of the anticoagulant therapy after radiofrequency ablation of the cavotricuspid isthmus have not been sufficiently studied, therefore, the recommendations for prescribing the anticoagulant therapy usually do not distinguish between atrial flutter and atrial fibrillation. In contrast to the case of atrial fibrillation, the effectiveness of the interventional treatment for typical atrial flutter reaches 90%. This procedure may save the patient from a long-term anticoagulant therapy in the absence of recurrence of typical atrial flutter. The decision to stop the anticoagulant therapy after successful radiofrequency ablation of the cavotricuspid isthmus should take into account the potential induction of atrial fibrillation in patients undergoing the interventional treatment. In addition to the CHA2DS2-VASc scale, which characterizes the patient's comorbidity, it is important to take into account the echocardiographic morphofunctional criteria to assess the risk of atrial fibrillation. Currently, this protocol is not regulated in the clinical guidelines. The analysis of the literature data and the authors' own experience allow us to conclude that the optimal time for stopping the anticoagulant therapy is a relapse-free period of 34 months after the radiofrequency ablation of the cavotricuspid isthmus, since it is at this time that the effectiveness of the interventional treatment can be objectified.

Background: Atrial fibrillation (AF) is the most common arrhythmia in clinical practice and is associated with an increased risk of death, progression of heart failure, and the development of cardiogenic thromboemboli. Despite the significant success in the management of AF in the paroxysmal form, the results of the treatment for patients with persistent forms of AF remain unsatisfactory. Though the surgical approach provides higher rates of efficiency regarding the restoration of a sinus rhythm, transmural lesions are not always attainable, as a result, the rate of AF recurrence in the long-term period remains fairly high. It is also impossible to create ablative patterns to the mitral and tricuspid valves during thoracoscopic epicardial ablation, which can cause the development of recurrent AF, perimitral and typical atrial flutter. Therefore, the development of hybrid approaches combining the advantages of catheter and thoracoscopic techniques is an urgent task of contemporary surgical and interventional arrhythmology. Aims: to estimate the immediate results of a hybrid approach in the management of patients with persistent AF. Methods: We report the first experience of a hybrid treatment of patients with persistent AF. 6 patients aged 53-64 years (1 female, 5 males) were included in the study. At the first stage, thoracoscopic epicardial bipolar ablation was performed (modified GALAXY protocol); the second stage (in 3 to 6 months after the thoracoscopic stage) included an intracardiac electrophysiological study with three-dimensional endocardial mapping followed by endocardial ablation. Results: The thoracoscopic stage of the hybrid treatment included ablation according to the box lesion scheme using a bipolar irrigation equipment. No lethal outcomes and severe, life-threatening complications were registered. The duration of the inpatient period was 510 hospital-days. The 2nd stage of the hybrid treatment was limited to intracardiac electrophysiological examination only in 2 patients. In 4 patients, epicardial radiofrequency ablation was complemented by endocardial radiofrequency exposure. In 3 of the 4 patients who underwent endocardial radiofrequency ablation, catheter ablation of the mitral and cavotricuspid isthmus was required because of the induction of perimitral and typical flutter, respectively. After the 2nd stage of the hybrid treatment, at the time of discharge all the patients maintained a stable sinus rhythm. There were no severe complications or lethal outcomes. Conclusion: a hybrid approach in the AF management is a safe and effective method of treatment, which combines the advantages of minimally invasive surgery and endocardial intervention in patients with persistent AF. The technique is safe and has acceptable short-term results.

Abstract The sorption of uranium and thorium fluorides by activated carbon from the eutectic was studied. The sorption isotherms of both fluorides at a temperature of 650°C have a pronounced convex character and are described by the Langmuir equation. Experiments were carried out on the sorption of protactinium by activated carbon AG-3 at 650°С from a melt of alkali metal fluorides LiF–NaF–KF containing thorium and neodymium fluorides. It was found that with an increase in the concentrations of neodymium or thorium fluorides, the value of protactinium sorption diminishes, and in the case of thorium fluoride, the decrease occurs to a greater extent. When protactinium is sorbed by activated carbon with metallic sodium, the sorption enhances by a factor of 20 at the 30% sodium content in the carbon. The separation factors of protactinium from other actinides rise with increasing sodium content in the carbon.

Background: Thoracoscopic ablation is an effective treatment of patients with atrial fibrillation. Nowadays, 2 types of ablative devices are available in clinical practice allowing one to perform the thoracoscopic procedure Medtronic and AtriCure. However, the contemporary clinical literature does not have enough data that would compare these two approaches. Aims: to perform a comparative analysis of the short-term results of two minimally invasive strategies in thoracoscopic ablation for atrial fibrillation. Methods: 232 patients underwent thoracoscopic ablation for atrial fibrillation in two clinical centers for the period from 2016 to August 2021. The patients were divided into 2 groups. The first group was represented by those patients to whom a Medtronic device was applied (n=140), the second group was treated with an AtriCure device (n=92). The patients were comparable in their age, gender, initial severity of the condition. The follow-up consisted of laboratory tests, chest Х-ray, electrocardiography, 24-hour Holter monitor, echocardiography. The structure and prevalence of postoperative and intraoperative complications, specifics of the postoperative period were compared between the two groups. Results: According to the structure and prevalence of intraoperative complications the 2 groups are comparable to each other: 4.3% and 1.1% for the 1st group and 2nd group, respectively (p 0.05). The postoperative complications had developed in 6 (4.3%) and 5 (5.4%) patients in groups 1 and 2, respectively (p 0.05). At the time of discharge from hospital, a sinus rhythm was registered in 93.6% of patients (1st group), and 85.9% (2nd group) (p 0.05). Conclusions: Both strategies have demonstrated comparable short-term results in patients with lone atrial fibrillation. A further research is needed to evaluate the effectiveness of this strategy in a long-term period.

Background: The level of troponins after cardiac surgery always exceeds the reference values, however, the interpretation of these changes is difficult. Aim: To determine the relationship between the high-sensitivity cardiac troponin I and troponin T levels and the risk of heart failure (HF) development within 24 hours after the heart surgery. Methods: A prospective, observational, single-center study included 70 patients undergoing elective heart surgery. The patients were retrospectively divided into two groups based on the development of HF in the first 12 hours after the surgery. The group without HF included 57 patients, the group with HF included 13 patients. Results: The levels of highly sensitive Troponin I (HsTI) in patients who underwent elective heart surgery without complications were 61 times higher than the upper limit of the normal values, in those with the development of HF they were 111 times higher than the upper limit of the normal values. The levels of highly sensitive Troponin T (HsTT) were 25.5 times and 51 times the upper limit of the normal values, respectively. The level of HsTI at the end of the surgery can be a predictor of the HF development, regardless of the use of cardiac bypass (threshold value =1483 ng/l), as well as a predictor of the need for inotropic support for 2 days or more, regardless of the operation type (threshold value = 1573 ng/l). There was a direct moderate correlation of the HsTI level at the end of the operation and 6 hours after the operation with cumulative hemohydrobalance for 24 hours, which was 60% higher in patients with HF than that in patients without complications. Conclusion: In uncomplicated patients, the level of highly sensitive troponins T and I in the postoperative period is 2561 times higher than the upper limit of the normal values, and with the HF development it is 51111 times higher. Highly sensitive troponins can be considered as predictors of the HF development and the duration of inotropic support. The increase in the level of troponins is influenced by the duration of cardiac bypass and the volume of infusion therapy in the perioperative period.

Background: The use of artificial circulation in surgical myocardial revascularization is one of the key pathogenetic factors in the development of the oxidative stress and systemic inflammatory response in the postoperative period. Aims: the purpose of the study was to describe the dynamics of the induced blood oxidation parameters during coronary artery bypass surgery in the conditions of artificial circulation and on the working heart. Methods: The study included 64 patients who underwent coronary bypass surgery, with 31 (48.4%) on-pump patients and 33 (51.6%) off-pump patients. The oxidative stress simulations were conducted under the in vitro conditions. The blood oxidation-induced values were studied using a biological oxygen monitor. Results: In patients with coronary heart disease, regardless of the choice of the revascularization method (on-pump / off-pump), we observed statistically significantly (p 0.05) higher initial and maximum blood oxidation rates, the oxidative activity factor, and a shorter initiation period than those in healthy volunteers. No significant differences were found by the inter-group comparison analysis both 10 days and 6 months post-surgery. Conclusion: The indicators of induced blood oxidation do not depend on the method of revascularization during coronary bypass grafting (artificial circulation or a working heart). The changes in the parameters indicating activation of the oxidative and antioxidant blood systems may be transient by their nature and occur in the early postoperative period.

Background One of the most arrhythmias associated with atrial fibrillation (AF) is typical atrial flutter (AFL). The main methods of surgical treatment of these arrhythmias is catheter ablation. The problem of catheter ablation strategy for these coexistentarrhythmias is not solved. Purpose: To assess the effectiveness of long-term maintenance of sinus rhythm in a two-stage approach to the interventional treatment of atrial fibrillation associated with typical atrial flutter. Methods: The study included 34 patients aged 41-82 years with AF and coexistent typical AFL. Female 11 (32,35%), male 23 (67,35%). Randomization 1:1. Group 1 (n=17) has been performed radiofrequency ablation (RFA) of the cavotricuspid isthmus (CTI) with radiofrequency catheter isolation of the PV. Group 2 (n=17) has been performed only RFA of CTI. AF and AFL recurrences rate has been evaluated in both groups. Follow-up period 12 months. Results: Procedure duration and fluoroscopy time were less in group 2 that those in group 1. Extended intervention in group 1 was accompanied with complications in two cases. There were no significant differences in AF recurrence rate in both groups (p=0,43183). AFL recurrences has not been found in both groups. Conclusion: One stage ablation approach in AF patients with coexistent AFLassociated with increaseprocedure duration and fluoroscopy time. The frequency of AF recurrence in patients who underwent extended intervention (catheter isolation of the PV and RFA CTI) and in patients who underwent only the elimination of typical atrial flutter, was not statistically significantly different (p = 0.43183). In the presence of AF and typical atrial flutter, a two-stage approach to interventional treatment should be regarded as appropriate.

Objective: to evaluate the role of cardiopulmonary test in the diagnosis of heart failure with preserved ejection fraction in patients with atrial fibrillation. Material and Methods: 138 patients with atrial fibrillation were included in our study. Using HFA-PEFF algorithm (algorithm for diagnosis of heart failure with preserved left ventricular ejection fraction) all patients were initially divided into 3 groups: low probability of heart failure - 23 patients, intermediate probability - 96 and high probability - 19 patients. The stress-test allowed to precisely assess of patients at intermediate risk and finally form the groups: Group 1 without heart failure, 85 patients (61.6%); Group 2 patients with heart failure and preserved ejection fraction, 53 patients (38.4%). The next diagnostic stage was cardiopulmonary test. Results: during CPT, the maximum anaerobic exercise threshold was 6.8 and 4.85 METS for the first and second groups, respectively (p0.001), reflecting lower exercise tolerance in the second group of patients. Analysis of variance (ANOVA) demonstrated a statistically significant increase in pro-BNP levels with a decrease in peak VO2 (p0.001). Also, analysis of variance demonstrated a significant statistical difference with respect to systolic pulmonary artery pressure in the subgroups with severely, moderately reduced oxygen consumption and in the group with normal peak VO2 (p=0.01). ROC analysis determined a peak VO2 of 20 ml/kg/min, above which the HFA-PEFF algorithm was unlikely to detect heart failure (AUC 0.73; confidence interval 0.65-0.82; p=0.043; sensitivity 85%; specificity 51%). Conclusion: Cardiopulmonary test is a reliable instrumental noninvasive method of investigation in the diagnosis of heart failure with preserved ejection fraction. Keywords: atrial fibrillation; chronic heart failure; cardiopulmonary test; ergospirometry

Objective: to study the features of the course of the wound process both with the isolated use of hexethidine and photoditazine, and in combination with ultrasound therapy. Materials and Methods. The in vivo experiment was performed on 144 animals (male Wistar rats) divided into 4 equal groups. A purulent wound model (S=150mm2) was formed in all rats, which was treated with the studied combinations with and without ultrasound therapy. The percentage of area reduction, healing rate, microbial contamination, and morphological picture of wounds were evaluated. Results. In the groups treated with the combination we developed, complete wound healing had occurred by 15 days. The greatest activity was in phase I of the wound process, which is confirmed by the maximum wound healing rate (1-5 days from the start of treatment), as well as by the morphological picture. At the same time, in the group with the use of ultrasound therapy the indices of microbial siltation and percentage of area reduction were reliably better in comparison with the isolated use of the combination. Conclusion. The developed combinations have a positive effect in the treatment of purulent wounds, speeding up the healing process and reducing microbial contamination.

Atrial fibrillation is one of the most common types of cardiac arrhythmia observed in clinical practice. Despite advances in the diagnosis and treatment, atrial fibrillation remains one of the leading causes of cardiovascular mortality and morbidity. In addition, atrial fibrillation is quite often combined with other pathologies of the cardiovascular system and is a marker of an unfavorable outcome. Several previous studies have demonstrated reduced survival in patients with coronary artery disease and atrial fibrillation who have not undergone surgery for arrhythmia. According to other data, the presence of preoperative atrial fibrillation among patients undergoing isolated coronary artery bypass grafting was associated with significantly higher rates of major postoperative complications. Nowadays, no one doubts the fact that atrial fibrillation during a coronary artery bypass surgery is a risk factor for increased hospital mortality, postoperative morbidity and leads to a decrease in the long-term survival. The studies confirm the necessity of surgical ablation for atrial fibrillation during coronary revascularization to reduce both short-term and long-term postoperative mortality and late complications.

Abstract The sorption of neodymium and thorium fluorides by AG-3 activated carbon from molten alkali metal fluorides LiF–NaF–KF has been studied. The sorption isotherm of neodymium fluoride at 650°C has a pronounced convex and is adequately described by the Langmuir equation. The sorption of thorium fluoride under the same conditions is much weaker than that of neodymium fluoride, which is determined by the size of the neodymium and thorium fluoride complexes. The kinetic dependence of the sorption of neodymium fluoride at a temperature of 650°С is adequately described by a first-order equation for a reversible reaction. The temperature dependence of sorption capacity in the range 550–750°С passes a maximum within 600–650°С.

The review provides information on the Porous structure and sorption properties of carbon and carbon-inorganic sorbents obtained from organic technogenic substrates are reviewed. Polymer materials, intermediate products of the oil-extracting and oil-refining industries, agricultural waste, and cellulose and its derivatives such as chitin and chitosan have been considered as the substrates of technogenic origin. The available methods to prepare adsorbents from organic technogenic substrates have been analyzed; parameters of porous structure and sorption activity of the adsorbents with respect organic compounds and non-ferrous metal cations have been reported.

Background: Adequate diagnosis of recurrent atrial fibrillation after the surgical treatment in patients with paroxysmal forms of the disease appears to be a difficult task. Aims: The manuscript is devoted to a comparative analysis of the results of subjective and objective assessment of atrial fibrillation recurrence after cryoballoon ablation of the pulmonary veins. Material and methods: 301 patients were included in the study. All of them consequentially underwent cryoballoon ablation of the pulmonary veins in the period of October, 2016 November, 2019. The inclusion criteria were as follows: symptomatic atrial fibrillation; confirmation of atrial fibrillation by instrumental diagnostic methods. The exclusion criteria were the following: a combination of atrial fibrillation and atrial flutter at the time of surgery; history of open-heart procedures and catheter procedures to cease atrial fibrillation; the presence of concomitant cardiac and "arrhythmogenic" pathology. Results: In the period of May 01-30, 2020, 100% (n=301) of the patients included in the study were assessed by the method of targeted survey. The median duration of the postoperative period to the time of a patient's survey was 21 (3; 43) months. The interviews have shown that 136 (45%) patients noted a return of complaints associated with atrial fibrillation recurrence in the postoperative period. There was a clear tendency towards a decrease in the total number of patients with complaints of the clinical recurrence of the disease, depending on the time elapsed since the surgical procedure. The longer the period from the moment of surgery, the lower the number of patients with recurrence. Of 136 patients with recurrent complaints associated with atrial fibrillation, 97 (71%) were able to conduct the daily electrocardiogram monitoring. Of these, the instrumental recurrence of atrial fibrillation was confirmed in 59 patients, which amounted to 20% of all the patients included in the study (n=301). Conclusion: To establish the true number of atrial fibrillation recurrence after cryoballoon ablation of the pulmonary veins, a targeted survey of patients is desirable for up to 12 months after the surgery. The patients with complaints which suggest atrial fibrillation recurrence, even if these complaints do not correspond to the preoperative ones, should be invited for the instrumental diagnostics of arrhythmia.

Treatment of purulent wounds is an urgent problem in modern surgery. The need to develop new combinations that improve the treatment process is one of the priorities. Materials and methods. A purulent wound model was formed on 180 Wistar rats divided into 5 equal groups. The percentage of reduction of the wound area, healing rate, microbial contamination were evaluated, histological examination was performed. Results. In groups with the use of a photosensitizer, complete wound healing occurred by 15 days. The maximum healing rate of the combined use of hexethidine and photoditazine occurred in the first phase of the wound process, and microbial contamination by the 10th day was less than 15 thousand times compared to the control, and 187,5 times - with the comparison group (p < 0,05). Conclusions. The developed combinations have a positive effect on the course of the wound process, accelerating wound healing and reducing microbial contamination.

The study involved 23 patients (23 eyes) with neovascular glaucoma against the background of proliferative diabetic retinopathy. The first stage was the intravitreal injection of Lucentis, then with IOP > 25 mm Hg - transscleral cyclophotocoagulation and after 2 weeks panretinal laser coagulation in ischemic zones; with IOP < 25 mm Hg - panretinal laser coagulation in ischemic zones. At all observation periods there was a statistically significant decrease in IOP and in rubeosis. One week after the last stage of treatment the overall decrease in IOP was 33.4 % of the initial values, rubeosis was not detected. The application of Lucentis in combination with transscleral cyclophotocoagulation in the treatment of neovascular glaucoma against the background of proliferative diabetic retinopathy allows to achieve stable IOP normalization, preserving residual visual functions and reducing the risk of hemorrhagic complications.

The article presents two clinical cases of delayed restoration of the sinus rhythm in patients with long-term persistent atrial fibrillation after the procedure of thoracoscopic radiofrequency fragmentation of the left atrium. The necessity of continuing attempts to restore the sinus rhythm up to the end of the "blind period" (90 days) is discussed.

Approaches to the technology developed by OKBM Afrikantov for creating a supercomputer twin of a nuclear power plant on the basis of a three-level model are described. A software implementation of this technology based on homegrown software is proposed. Experience in using the technology is shown for the Yasen-M project, RITM-200, and BN-800.

The method of non-invasive proton-beam ablation of an arrhythmogenic substrate of ventricular tachycardia in patients with structural heart disease is aimed at eliminating triggers and/or destroying re-entry mechanisms using a proton beam described.

Objective. To improve the results of treatment for the patients with non-paroxysmal atrial fibrillation (AF) in combination with isthmus-dependent (typical) atrial flutter (AFL) by determining the optimal surgical tactics.Material and methods. The research based on the study of treatment results for 37 patients who are consequentially underwent thoracoscopic radiofrequency fragmentation (TRF) of the left atrium (LA) in the period from April 2017 to December 2019. All of the patients suffered from a combination of 2 types of arrhythmias: non-paroxysmal AF and AFL. Depending on history of catheter ablation (CA) of cavotricuspid isthmus (CTI) before TRF, all patients divided into 2 groups: group 1 - there was anamnesis of CA of CTI before TRF (N = 16; 43%); group 2 - there was no CA of CTI before TRF of the LA (N = 21; 57%). In the postoperative period, all patients underwent examination and interviewed regarding cardiac arrhythmias. At the time of April 1, 2020, information about heart rhythm and its disorders during follow-up period was received from 100% of patients. The duration of the follow-up period after TRF was 17 (3; 35) months.Results. There was no supraventricular tachyarrhythmias (SVT) during all follow-up period after TRF among the patients of group 1. There was 8 patients (38%) of group 2 with AFL, which is developed in the period from 1 to 6 months after TRF. All these patients underwent a CA of CTI after the end of a “blanking” period. There was 2 of 8 patients with developing of SVT after CA of CTI. The source of new rhythm disorder was the ablation line formed during TRF on the roof of the LA.Conclusion. In order to achieve long-term freedom from SVT requiring surgical intervention in patients suffering from a non-paroxysmal AF in combination with a typical AFL it is reasonable to perform catheter radiofrequency ablation of CTI at the first stage before TFR of the LA.

The effect of artificial light with different spectral compositions (white, WW; white–red, WR; white–blue, WB; and white–red—blue, WRB) on the wet weight, plant height, total leaf surface area, variable fluorescence parameters of photosystem 2 (PS2), and the content of the total fraction of essential oils in 30‑ and 50-day-old Cinnamon Aroma basil plants was studied. Thirty-day-old basil plants adapted to WB light were characterized by the highest chlorophyll content and the highest value of the photochemical quenching coefficient of PS2 fluorescence but by the smallest wet weight and total leaf surface as compared to plants grown in light with a different spectral composition. A longer adaptation (50 days) of the basil to illumination of a different spectral composition at the same intensity led to plant alignment in terms of chlorophyll content and height. A positive correlation was found between changes in the photochemical quenching coefficient of PS2 fluorescence and wet weight in 50-day-old plants. Fifty-day-old plants grown in light with a high proportion of red radiation (WR and WRB) and having generative shoots with buds contained the largest amount of the total fraction of essential oils.

A “Quenching and Partitioning” (Q&P)–based heat treatment has been applied to rolled grinding steel (0.75 wt pct C-Mn-Cr) balls of 104-mm diameter to prevent their cracking during heat treatment. The conventional route of ball manufacturing includes rolling, water quenching interrupted when the bulk average temperature is 220 °C to 250 °C, and self-tempering in a large pile. This technology leads to cracking when the balls are made of steel of high hardenability. To overcome this deficiency, the Q&P principle is herein adopted by (a) adjusting the quenching duration to cool the ball center below the martensite start (Ms) temperature and (b) instead of self-tempering applying furnace tempering. The target bulk temperature of the ball that ensures an optimal “martensite/retained austenite” ratio inside the ball at the moment of water quenching interruption is determined as 125 °C to 170 °C. Quenching should be followed by tempering at 200 °C to 250 °C for stress release at the surface and carbon partitioning from martensite to austenite in the core. The resulting microstructure varies from tempered martensite in the “shell” layers to a mixture of martensite-bainite and retained austenite (RA) in the inner zones, where the austenite content is 25 to 30 vol pct. The carbon enrichment in austenite toward the core of the ball leads to balanced stresses and prevention of ball cracking. Q&P-heat-treated balls in an industrial-scale trial attained a uniform hardness of approximately 55 HRC through the cross section and a high fracture resistance under repetitive impacts of 6.8 kJ energy each.

The current problem with phosphorus fertilizers are shortage of rock phosphate from which it is produced and adverse impact of their production and use on the environment. A promising solution is use of phosphorus-rich biomass of microalgae as biofertilizer, but possible impact of such fertilizers on the biological activity and microbiome of soils remain unknown in many aspects. We investigated the effect of Chlorella vulgaris IPPAS C-1 (Chlorophyceae) biomass application on yield, biological activity, efficacy of the rhizobia- and cyanobacteria-based growth promoting formulations, as well as the microbiome of the soil during cultivation of beans (Phaseolus vulgaris L.) cvr. “Strela.” Total and specific yield, actual nitrification and denitrification, carbon dioxide and methane emission were determined for soil samples from the rhizosphere. The taxonomic structure of the prokaryotic community of the bean rhizosphere was determined by NGS of 16s rRNA gene amplicons on the Illumina platform. The metagenomic data were analyzed using software tools QIIME and VAMPS. It was found that the application of biomass of C. vulgaris IPPAS C-1 as a phosphorus biofertilizer increased the bulk yield of beans. It also allowed to achieve the specific yield (per plant) level provided by traditional fertilizers. The biomass application did not (i) impact the biological activity of the soil, (ii) did not increase the level of denitrification, and (iii) did not increase significantly the soil emission of the “greenhouse gases.” The Chlorella biomass application hamper the growth-promoting effect of the bacterial preparations made from rhizobia and cyanobacteria. Also, no significant changes in the taxonomic composition of the soil of the rhizosphere microbiome upon the application of the Chlorella biomass were revealed. Collectively, the results indicate the possibility of at least partial replacement of chemical fertilizers with phosphorus biofertilizers from microalgae biomass in the field growing of beans.

The article presents a comparative analysis of the main types of reserve fuel for boilers, including fuel oil, diesel fuel and liquefi ed petroleum gases. The main technological aspects and features of construction of fuel farms are analyzed. The economic aspects of the use of diff erent types of reserve fuel are considered. The thermal and cost costs of fuel storage and combustion are estimated. The calculation of emissions into the atmosphere of harmful substances, including nitrogen dioxide, nitrogen oxide, carbon monoxide, benzapyrene, sulfur dioxide, soot. The masses of emitt ed substances, their concentration in fractions of MPC, distances at which the maximum concentration of emissions is observed are determined. The prospects of using liquefi ed hydrocarbon gases and «Propane-Air» technology are substantiated.

Problem statement . Structural steel products are the bulk of the production of modern metallurgy. It is advisable to increase the mechanical properties of rolled products in the framework of technologies involving the use of rolling heating, which saves energy and reduces the production cost. Purpose . The choice of a rational scheme of rolling and post-deformation cooling of rolled steel made of structural steel. Material and Methods . The study material is 20 mm thick sheet steel made of S355J2 steel (EN 10025) micro-alloyed with V−Nb−Al complex. Methodology − tests for mechanical properties according to the requirements of EN 10025. Results . The mechanical properties of sheet metal are compared after performing standard hot rolling, normalizing rolling, controlled rolling, and also after controlled rolling with subsequent accelerated cooling in various modes. Conclusions . It is shown that by using controlled rolling with accelerated cooling to 460…530 °C, it is possible to significantly (by one third, up to category 500Q) increase the strength of steel with an increase in its cold resistance and at the same time maintaining plasticity at an acceptable level. Such an increase in the complex of properties is achieved without the use of heat treatment with special heating, which is an economically advantageous direction.

A prominent feature of stress-tolerant microalgae is their versatile metabolism, allowing them to synthesize a broad spectrum of molecules. In microalgae, they increase stress resilience of these organisms. In human body, they exhibit anti-aging, anti-inflammatory, and sunscreen activities. This is not surprising, given that many of the stress-induced deleterious processes in human body and in photosynthetic cell are mediated by the same mechanisms: free-radical attacks and lipid peroxidation. It is also worth noting, that the photosynthetic machinery of microalgae is always at risk of oxidative damage since high redox potentials and reactive molecules are constantly generated during its functioning. These risks are kept at bay by efficient reactive oxygen species elimination systems including, inter alia, potent low-molecular antioxidants. Therefore, photosynthetic organisms are a rich source of bioactive substances with a great potential for curbing the negative effects of stresses, acting on human skin cells on a day-to-day basis. In many cases these compounds appear to be less toxic, less allergenic, and, in general, more “biocompatible” than most of their synthetic counterparts. The same algal metabolites are recognized as promising ingredients for innovative cosmetics and cosmeceutical formulations. Ever increasing efforts are being put into the search for new natural biologically active substances from microalgae. This trend is also fueled by the growing demand for natural raw materials for foods, nutraceuticals, pharmaceuticals, and cosmetology, associated with the global transition to a “greener” lifestyle. Although a dramatic diversity of cosmeceuticals was discovered in macrophyte algae, single-celled algae are on the same level or even surpass them in this regard. At the same time, a large-scale biotechnological production of microalgal biomass, enriched with the cosmeceutical compounds, is more technically feasible and economically viable than that of macrophyte biomass. The autotrophic cultivation of microalgae is generally simpler and often cheaper than that of heterotrophic microorganisms. Cultivation in bioreactors makes it possible to obtain more standardized raw biomass, quality of which is less dependent on seasonal factors. Microalgae biotechnology opens many possibilities to the “green” cosmeceutical production. However, a significant part of microalgae chemo- and biodiversity remains so far untapped. Consequently, bioprospecting and biochemical characterization of new algal species and strains, especially those isolated from habitats with harsh environmental conditions, is a major avenue for further research and development. Equally important is the development of approaches to cost-effective microalgae cultivation, as well as induction, extraction, and purification of cosmeceutical metabolites. World scientific community is rapidly accumulating extensive information on the chemistry and diverse effects of microalgae substances and metabolites; many substances of microalgal origin are extensively used in the cosmetic industry. However, the list of extracts and individual chemicals, isolated from them and thoroughly tested for safety and effectiveness, is not yet very large. Although excellent reviews of individual microalgal cosmeceutical groups exist, here we covered all the most important classes of such compounds of cosmeceutical relevance, linking the patterns of their composition and accumulation with the relevant aspects of microalgae biology.

A prominent feature of stress-tolerant microalgae is their versatile metabolism allowing then to synthesize a broad spectrum of molecules with beneficial effects on many aspects of human body functioning. This is in line with the current understanding that many stress-induced deleterious processes in the human body and in photosynthetic cell are mediated by the same mechanisms such as free-radical attacks and lipid peroxidation. These related risks are kept at bay by optical screening of harmful UV, enzymatic ROS elimination systems, and potent low-molecular antioxidants. Microalgae synthesize a broad spectrum of compounds exerting antioxidant and/or UV-absorbing properties. In microalgae, they increase stress-resilience of these organisms. In human body, they exhibit photoprotective, antiaging, and sunscreen activities. Therefore, these algal metabolites were recognized as promising ingredients for innovative cosmetics and cosmeceutical formulations. Ever increasing effort is being invested into the search for new natural biologically active substances from microalgae. This trend is also fueled by the growing demand for natural raw materials for food, pharmaceuticals and cosmetology associated with the global transition to a "greener" lifestyle. Here, we review the currently accumulated knowledge about the main groups of cosmeceutical compounds from microalgae.

Coronary artery bypass grafting techniques have been unchangeable for many years, whereas development and enhancement of myocardial protection methods in coronary bypass grafting for patients with ischemic heart disease are still actual issues of current coronary surgery. Coronary artery bypass grafting techniques include the traditional/conventional technique with cardiopulmonary bypass, aortic cross-clamping and cardioplegia, off-pump and on-pump beating heart coronary artery bypass grafting. Coronary artery bypass grafting with cardiopulmonary bypass and cardioplegia remains the most common method of coronary revascularization. However the cardiac arrest inevitably leads to global cardiac ischemia, and current cardioplegias do not prevent ischemic damage to the myocardium in all cases, especially in high-risk surgical patients. Off-pump coronary artery bypass grafting allows preventing global myocardial ischemia (due to the constant native coronary blood-flow) and avoiding possible negative consequences of cardiopulmonary bypass use. The main limitations of this technique are associated with high risk of hemodynamic instability due to low cardiac output and systolic output caused by target arteries exposition. On-pump beating heart technique is a reasonable compromise between conventional on-pump coronary artery bypass grafting, cardioplegia and off-pump procedure. It is a safe and effective technique with outcomes that are equivalent or superior to the outcomes reported for conventional coronary artery bypass grafting in patients with unstable hemodynamics, low left ventricular ejection fraction and in high-risk patients. The literature review presents the results of on-pump beating heart coronary artery bypass grafting.

Conjugates of allocolchicine and a cetirizine analog have been synthesized as potential anti-inflammatory and anti-allergic drugs.

Актуальность. Хирургические вмешательства с использованием эндоскопической техники демонстрируют высокую эффективность при лечении пациентов с персистирующей формой фибрилляции предсердий. Минимальная травматичность торакоскопических процедур способствует популяризации подобных вмешательств по всему миру. В настоящее время торакоскопические вмешательства стали доступны для пациентов в Российской Федерации.Цель. Собрать и систематизировать данные о развитии торакоскопической аблации в Российской Федерации, выполняемой для лечения пациентов с изолированной формой фибрилляции предсердий.Методы. Выполненная работа охватила период операций, проведенных отечественными кардиохирургами до 1 января 2018 г. Для сбора данных респонденты заполняли регистрационную форму. В анкете регистрировали даты выполнения процедур, форму фибрилляции предсердий, наличие предшествующих катетерных процедур, инструмент для проведения операции, схему нанесения аблационных линий, метод закрытия ушка левого предсердия, большие осложнения вмешательства. Сбор регистрационных форм осуществлен посредством электронной переписки.Результаты. Получены и проанализированы данные 652 торакоскопических аблаций, выполненных в 10 кардиохирургических центрах России. Большую часть операций (92%) провели у пациентов с персистирующей формой фибрилляции предсердий. Аблационные линии наносились по двум основным схемам — Dallas Lesion Set и Box Lesion Set. Ушко левого предсердия выключено из внутрисердечного кровотока при помощи различных методов у 90,4% пациентов. Значимые осложнения, развившиеся главным образом на этапе освоения методики, зарегистрированы у 27 (4%) пациентов.Заключение. Представленная работа является первой попыткой собрать и систематизировать данные о новом методе хирургического лечения пациентов с фибрилляцией предсердий. Полученные данные позволяют сделать вывод, что торакоскопическая аблация становится распространенным методом хирургического лечения пациентов с изолированной формой фибрилляции предсердий в России. Этап освоения методики сопровождается осложнениями в любом кардиохирургическом центре. Тем не менее количество осложнений, даже на этапе освоения методики, остается на минимальном уровне, позволяющем рекомендовать торакоскопическую аблацию для лечения многочисленной группы пациентов с фибрилляцией предсердий.Поступила в редакцию 13 июня 2018 г. Исправлена 22 июля 2018 г. Принята к печати 23 июля 2018 г. Финансирование Исследование не имело спонсорской поддержки.Конфликт интересовАвторы заявляют об отсутствии конфликта интересов.Вклад авторовКонцепция и дизайн работы: О.Ю. Пиданов, А.В. Богачев-ПрокофьевСбор и анализ данных: Д.А. Елесин, О.А. Бобровский, П.А. Шиленко, П.А. Дурыгин, А.С. Зотов, C.А. Вачев, В.Е. Вайкин, С.Е. Мамчур, О.В. Сапельников, Д.О. БыстровНаписание статьи: О.Ю. ПидановРедактирование статьи: А.В. Богачев-Прокофьев, Э.А. ИваницкийСтатистическая обработка данных: О.Ю. ПидановУтверждение окончательного варианта статьи: О.Ю. Пиданов, А.В. Богачев-Прокофьев, Д.А. Елесин, Э.А. Иваницкий, О.А. Бобровский, П.А. Шиленко, П.А. Дурыгин, А.С. Зотов, C.А. Вачев, В.Е. Вайкин, С.Е. Мамчур, О.В. Сапельников, Д.О. Быстров

Studies of the impact of inorganic phosphorus (Pi), an important nutrient, on the growth and physiological parameters of single-celled algae are important for investigations of the dynamics of phytoplankton abundance and productivity in natural ecosystems as well as in industrial systems for the cultivation of microalgae. Difficulties in carrying out such studies are associated with the complex kinetics of Pi uptake by cells and the ability of microalgae to store phosphorus in their cells. This situation necessitates efficient methods for express monitoring of microalgal cultures, such as the methods based on the registration of optical properties of cells, in particular absorption and scattering of light and fluorescence of chlorophyll contained in the cells. Here, the results of monitoring the cultures of the chlorophyte Chlorella vulgaris IPPAS C-1 starving for phosphorus are described. It was found that both optical (light absorption in the bands of the key pigments—chlorophylls and carotenoids) and luminescent (variable fluorescence of chlorophyll) parameters closely reflect the culture condition. Registration of optical properties required correction for the contribution of light scattering to the overall extinction of light by microalgal cell suspensions. At the same time, the light scattering signal is an accurate measure of the total number of suspended particles in the suspension. However, it is difficult to monitor cultures containing a significant amount of light-scattering particles lacking photosynthetic pigments (such as heterotrophic bacteria). For such cultures, the use of variable fluorescence- based parameter Fv/Fm reflecting the maximum photochemical efficiency of the photosystem II is advisable.

Дефекты межпредсердной перегородки - вторые по частоте после дефектов межжелудочковой перегородки среди врождённых пороков сердца. Эндоваскулярное закрытие дефекта межпредсердной перегородки выполняют по строгим показаниям у пациентов со значимым сбросом крови слева направо. Развитие инфекционного эндокардита после транскатетерной имплантации окклюдера бывает чрезвычайно редким осложнением. В данном клиническом наблюдении рассмотрен случай развития инфекционного эндокардита митрального клапана (с развитием выраженной недостаточности) через 13 лет после эндоваскулярного закрытия дефекта межпредсердной перегородки у пациентки 39 лет. Перед выполнением хирургического вмешательства проведена комплексная антибиотикотерапия. В ходе операции выполнены удаление окклюдера дефекта межпредсердной перегородки, протезирование митрального клапана, пластика дефекта межпредсердной перегородки и резекция ушка левого предсердия. Послеоперационный период протекал без особенностей.