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Introduction. One of surgical methods for treatment of aortic valve (AV) pathology is Aortic Valve Neocuspidalization Ozaki procedure (AVNeo). Thus, according to the latest systematic review, freedom from reoperation within one, three, five years after AVNeo was 98%, 97% and 96%. Available references provide few descriptions of reoperations after AVNeo. Aim. To analyze the immediate results of AV reinterventions after AVNeo. Materials and methods. In the medium term, reinterventions after AVNeo were necessary for 11 patients (4.3%). The age of patients ranged from 26 to 69 years. 11 patients who underwent surgery included 6 males and 5 females. Four patients had class III-IV CHF, according to NYHA classification. Three patients had previously been operated on for infective endocarditis (IE), and five patients had bicuspid aortic valve. The duration of follow-up, from AVNeo surgery to reinterventions, ranged from 3 to 43 months. Results and discussion. All patients underwent an isolated AV intervention. The main causes of dysfunction were IE (six patients) and leaflet rupture in the commissural area (five patients). Seven patients underwent aortic valve replacement with mechanical valves, one patient — with aortic homograft valve, one patient — with tissue valve and two patients underwent valve repair. In the early postoperative period, one patient had bleeding with the development of cardiac tamponade and one patient had a haemorrhagic stroke. No patients had ARF, perioperative myocardial damage, sternal infection or permanent pacemaker implantation. Two patients died during the hospital period. Conclusions. AV reinterventions are associated with a high incidence of complications and deaths. Therefore, prevention of IE and commissure enhancement should reduce the frequency of repeated interventions, which is to be confirmed by prospective studies in large cohorts of patients.

Introduction. Regional blockades in children in ophthalmology operations are used not only for analgesia in the intra- and postoperative period, but also for the prevention of oculocardial reflex (OCR), postoperative nausea and vomiting (PONV). But there is still no convincing data on the advantages of the methods of retrobulbar blockade (RBB) performed under ultrasound guidance and parabulbar blockade (PBB) performed under ultrasound guidance. Aim. In the present study, we investigated the efficacy and safety of RBB under ultrasound guidance with ropivacaine 0.5 % for the prevention of OCR and postoperative pain, as well as PONV when detected with PBB of ropivacaine 0.5 % under ultrasound guidance upon detection of enucleation of the eyeball. Materials and methods. A prospective randomized arterial study was performed for the period 2016–2022. The study included 110 patients with established inclusion criteria. The patients were divided into two groups: 55 patients who performed a RBB + ultrasound and 55 patients who performed a PBB + ultrasound. Evaluated: the likelihood of the introduction of opioid analgesics, the quality of anesthesia, the duration of the block and the likelihood of complications. Results. There was a decrease in intraoperative diseases in the RBB + ultrasound group, where the average dose of fentanyl was increased by 4.1 ± 1.4 μg/kg, and in the PBB + ultrasound group it was 9.7 ± 1.8 μg/kg (p < 0.05 ). The time to the first frequency of the analgesic in the postoperative period was 6.7 ± 1.8 hours in the PBB + ultrasound group, and 11.7 ± 3.3 hours in the RBB + ultrasound group (p < 0.05). Conclusions. There was a significant difference in analgesic efficacy between RBB + ultrasound and PBB + ultrasound. It was revealed that RBB + ultrasound reduces intraoperative opioid requirements, stable intraoperative hemodynamics and longer postoperative analgesia. Therefore, the use of RBB + ultrasound for enucleation of the eyeball in children with retinoblastoma is the preferred technique.

This paper discusses the results of siliceous microfossils studies performed in a “staircase” of four isolation basins (33.7 m–2.9 m a.s.l.) on Big Solovetskiy Island (Solovki Archipelago, the White Sea). Diatoms were used as a primary group for paleoinferences, while chrysophyte cysts and sponge spicules also demonstrated high indicative potential. In all study lakes, the siliceous microfossils stratigraphy revealed three main stages of their evolution, i.e. large-basin, transitional and small-lake stages, each characterized by certain composition of the diatom assemblages and floristic diversity, relative abundances of chrysophyte cysts and sponge spicules, and siliceous microfossils concentrations. In the uppermost lake, glaciolacustrine environments unfavorable for aquatic biota existed during the large-basin stage. The proglacial lake stage terminated prior to ca. 10.4 cal ka BP, followed by a (semi)terrestrial episode before the transition to small-lake environments. In the other three lakes, marine environments were inferred at the earlier stage, characterized by the predominance of marine and brackish-marine diatoms, increased proportions of sponge spicules and low “cysts to diatoms” ratio. At the transitional marine-freshwater stage, mass growth of small fragilarioid diatoms and decreased abundances of spicules indicated unstable environments, while increased proportions of cysts pointed to progressive freshening of the basins. The duration of the marine-freshwater transition expectedly prolonged from ca. 200 yr in the upper basin (16.6 m a.s.l) to ca. 500 yr in the lowermost lake (2.9 m a.s.l.). The isolation from the sea took place between ca. 6.3 and 1.4 cal ka BP. At the small-lake stage, siliceous microfossils stratigraphies reflected local specifics of the basins and their catchments. We argue that besides traditionally used diatom data, relative and absolute abundances of siliceous microfossils also possess high indicative value for isolation basin studies. Our study demonstrated that marine waters on Big Solovetskiy Island never reached ca. 34 m a.s.l. during the Holocene, unlike the western coast of the Onega Bay where the Preboreal marine intrusion was recorded even at higher elevated localities. Different rates and amplitudes of shoreline displacement are thus suggested for the inner and outer parts of the Onega Bay. During the mid-Holocene Tapes transgression, before ca. 6.3 cal ka BP, the relative sea level on Big Solovetskiy Island exceeded 17 m a.s.l. The average estimated rates of the shoreline retreat during the second half of the Holocene gradually decreased from 0.28 cm year−1 to 0.2 cm year−1, indicating slowed isostatic uplift.

Self-supporting films and thick-walled moldings (blades) were obtained from solutions and melts of multiblock (segmental) copoly(urethane-imides). The initial copoly(urethane-imides) were obtained on the basis of aliphatic polyesters: poly(propyleneglycol), poly(diethyleneglycoladipinate) and polycaprolactone, dianhydride of 1,3-bis(3’,4-dicarboxyphenoxy) benzene and aromatic diamines: 4,4’-bis-(4”-aminophenoxy)biphenyl and 1,4-bis(4’-aminophenoxy)diphenylsulfone. Samples of films and moldings were studied by IR spectroscopy, TGA, DSC and mechanical analysis under static and dynamic (DMA) experimental conditions. It is assumed that the diff erences in the properties of films and moldings are due to an increase in the proportion of aromatic blocks due to microdestruction of polymer chains and increased interfacial interactions of polyester and urethanimide microphases (blocks) in polymer systems during the processing of polymers from the melt by injection molding.

The physicomechanical properties and structure of mullitecorundum unformed refractories were investigated and tests of a pilot batch of refractory products for various purposes were carried out. The effect of the addition of nanoscale SiO2 (1 wt. %) on strength, structural (density, porosity) and operational characteristics of unformed refractories. The results show that this additive contributes to the formation of a structure with high apparent density and compressive strength (2,93 and 2,98 g/cm3, 87,3 and 162,1 MPa, respectively, for two types of refractories), reduces open porosity from 20 to 14 %, and also increases the resistance of refractory products (by the duration of their operation) by 25‒35 % compared to the resistance of the base refractory. The use of SiO2 nanoparticle additives reduces the consumption of refractory products and raw materials for their production, and also increases the profitability of production. Ill. 2. Ref. 19. Tab. 4.

The samples of concrete based on ferroalloy slag with cement and fly ash were produced by the method mechanochemical activation. The chemical, phase and granulometric composition, specific surface area, morphology and strength characteristics of the samples were investigated. Ill. 8. Ref. 10. Tab. 5.

The aim of the article is to develop a scientific and methodical support for the forensic cost evaluation of real estate objects defferent from the federal appraisal standards. The authors solve the problem of comparative analysis of the professional activity of a real estate appraiser and a forensic expert who determines the market value, they also reveal their formal and substantive differences. They come to a reasonable conclusion about the necessity to develop a special methodology for forensic cost evaluation, as a study focused on the judicial system and considering the modern achievements in construction sciences, international valuation standards.The proposed methodology includes the analysis of two evaluations presented by the litigants and the fair (equilibrium) value of the property in a forensic expert’s opinion. The authors offer to compare two cost models identifying the critical parameters that led to the formation of the initial cost interval.The proposed version of scientific and methodical support does not require changes in the legislation and federal evaluation standards, but it involves the development of the guidelines for determining fair value by comparing the estimates submitted to the court by the parties to the dispute. The suggested methodology presents some additional opportunities for the development of a system of pre-trial resolution of disputes.

Highlights. A retrospective analysis of the patients’ data after Ozaki operation in four Russian Medical Centers was carried out. A comparative gender assessment of the immediate and medium-term results of Ozaki operation was performed.Aim. Gender assessment of Ozaki operation immediate and mid-term results in patients with aortic valve (AV) pathology.Methods. A retrospective multicenter study enrolled 251 patients (135 women, median age 66 (60–70) years old) who underwent Ozaki operation (2017–2020) was carried out in four centers in Russia. After propensity score matching, 92 patients were selected (mean age 65.8±10.8 years old). Two groups were formed in the gender structure: 46 females (average age 67.8±6.3 years old), 46 males (average age 63.8±15.4 years old). The main cause of AV dysfunction was severe aortic stenosis – in 86 (93.5%) cases. Chronic heart failure of III–IV functional class according to NYHA was observed in 26 (28.3%) patients. A bicuspid AV was in 24 cases (26.1%). The primary endpoint was hospital mortality. Postoperative complications and mid-term results (three-year overall survival and freedom from reoperation on AV) were assessed as secondary endpoints; the median follow-up period was 23 (18–33) months.Results. There was no statistically significant difference between the groups in the duration of surgery (275 minutes for females and 285 minutes for males, p = 0.4), cardiopulmonary bypass (98 minutes for females and 115 minutes for males, p = 0.3), aortic clamping (80 minutes for females and 93 minutes for males, p = 0.7). Hospital mortality among the studied patients did not differ: in the female group – 2.2% (1 case) and 0 in the male one, p = 0.9. There were no significant differences in postoperative complications: sepsis (2.2% in women and 0 in men, p = 0.9), superficial wound infection (8.7% in women and 6.5% in men, p = 0.9). Acute kidney injury, stroke, pacemaker implantation, resternotomy for bleeding were not observed in any patient. Three-year overall survival was 91.8% in females and 91.6% in males, p = 0.8; three-year freedom from reoperation – 94.4% for females and 100% for males, p = 0.1.Conclusion. Ozaki operation is equally reproducible with the same hospital mortality, postoperative complications, and medium-term outcomes in both females and males.

The aim was to study the analysis of cephalometric images of patients with distal occlusion of the dentition. The parameters obtained on cephalometric images were studied, divided into groups according to the principle of measurements (linear, angular) and their morphological affiliation (cranial, gnathic, dentoalveolar). Analysis of angular and linear cephalometric indicators of patients with malocclusion class II of the dentition made it possible to determine the mutual influence of cranial, gnathic and dental alveolar parameters. The position of the apical base of the upper jaw in the sagittal plane and the position of the chin protrusion relative to the anterior part of the skull base correspond to the average values of the age norm. The angle characterizing the relationship between the plane of the base of the upper and lower jaws is reduced. Angular parameters characterizing the ratio of the anterior points of the apical bases of the upper and lower jaws, the position of the plane of the base of the lower jaw relative to the anterior part of the base of the skull, the total angle Bjork is reduced. The position of the plane of the base of the upper jaw relative to the anterior part of the base of the skull corresponds to the average values of the age norm. The protrusion of the incisors of both the upper and lower jaws is caused by certain changes in their angles of inclination. Changes in the gnathic parameters of cephalometric images had deviations from the norm both in the direction of increase and in the direction of decrease.

The article presents the results of field studies conducted in 2018-2020 on the leached chernozem of the Volga foreststeppe. The objects of the research are the varieties of spring wheat Tulaykovskaya 10 (control), Yoldyz and Tulaykovskaya 108. At seeding rates of 5.0 and 5.5 million viable seeds per 1 ha the effect of mineral fertilizers was studied. The fertilizers were represented by a complete NPK mineral fertilizer of 16 kg a.i. and by top-dressing with mineral nitrogen fertilizer in the tillering phase at the doses of 30, 60 and 90 kg a.i./ha against this background. An increase in the seeding rate of seeds from 5.0 to 5.5 million seeds per 1 ha led to a significant increase in the yield of spring wheat in all years of study (by 0.11-0.26 t/ha), the weight of 1000 seeds – by 1.44 g (LSD05 = 1.14), the nature of grain - by 8 g/l (LSD05 = 5). The effect of top-dressing with nitrogen fertilizers has been proved – the increase in yield ranged from 0.15 to 0.28 t/ha over three years on the average, the maximum from a dose of 60 kg a.i. A statistically significant increase in the weight of 1000 seeds was provided by nitrogen fertilization in doses of 60 and 90 kg a.i./ha – by 2.79 and 1.87 g, respectively (LSD05 = 1.47), grain nature increased at doses of 30, 60 and 90 kg a.i./ha by 34, 23 and 16 g/l, respectively (LSD05 = 2). The average yield of spring wheat varieties with the selected combination of factors (5.5 million seeds/ha, N60) was in the range of 2.64-2.70 t/ha with a mass of 1000 grains 44.03-44.56 g, the nature of grain 765-783 g/l. The studied varieties differed in responsiveness to nitrogen fertilization (N60 against the NPK background): Tulaykovskaya 10 (+0.43 t/ha), Tulaykovskaya 108 (+0.39 t/ha), Yoldyz (+0.24 t/ha). Increases in yield from an increase in the seeding rate were 0.20 (Yoldyz), 0.25 (Tulaykovskaya 108) and 0.26 t/ha (Tulaykovskaya 10). In general, according to the experiment relative to the control variety Tulaykovskaya 10, the variety Yoldyz stood out with a stable increase in yield over the years of research (+0.08 t/ha), statistically significant in years with insufficient moisture. The Yoldyz variety was distinguished by an increased profitability of cultivation – up to 59.4 % at a seeding rate of 5.5 million viable seeds/ha against the background of applying mineral fertilizers N16P16K16 for pre-sowing soil cultivation.

Investigations of methane conversion in mixtures CH4–CO2 and CH4–O2 of various composition, pressure, and temperature processed by pulsed nanosecond discharges of various types and durations were carried out. The main products of carbon dioxide conversion (dry reforming) of methane were carbon oxide (CO), hydrogen (H2), ethane (C2H6), and carbon (C). Gas mixture treatment by discharges with pulse duration 1, 5, and 15 ns demonstrated that the energy efficiency of carbon dioxide conversion of methane depends on the power of the discharge pulse. Dependencies of CH4 conversion on gas mixture pressure for spark, diffuse, and corona discharge showed that the most efficient dry reforming of methane occurred in spark discharge with pulse duration of 15 ns at a pressure of 1 atm. with energy cost of conversion of one CH4 molecule being 15 electron-volts per molecule. The main products of oxidative conversion of methane were ethane and ethylene C2H4. It was shown that the catalyst NaOH/CaO was considerably more effective than nickel catalyst, and the use of it allowed to increase methane oxidative conversion degree by more than an order of magnitude. It was found that CH4 oxidative conversion and C2H6 yield were growing up with an increase in temperature, whereas C2H4 yield began to decrease at a temperature more than 420 K. The most efficient oxidative conversion of methane was realized in spark discharge in the presence of NaOH/CaO catalyst with energy cost of conversion of one CH4 molecule being 50 electron-volts per molecule.