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The results of studies of the influence of Y as a reactive element on the properties of TiAlN coatings obtained by the method of vacuum-arc deposition are given. Changes in the structure and properties were analyzed using SEM in combination with EDX, XRD, indentation analysis and wear analysis. It is shown that the presence of Y changes the crystalline phase of the Ti0.6Al0.34Y0.06N coating. It consists of a combination of a cubic NaCl structure (basic phase) and a wurtzite structure (additional phase). In addition, it leads to a small grain size (12 nm) and a nano-columnar structure. The high hardness is partly the result of solution hardening due to the inclusion of larger Y atoms in the TiAlN lattice at the locations of the metal atoms. The reduced grain size of 12 nm also helps to increase the hardness of the coating. The hardness is 31 ± 2.5 GPa, the modulus of elasticity is 394.8 ± 35.8 GPa. The residual stress is approximately three times (−3352 ± 64 MPa) higher than the TiAlN coating (−720 MPa). In addition, a high level of compressive stress contributes to an increase in hardness, since defects responsible for their own compressive stress are an obstacle to dislocation movement. The improved hardness of the experimental coating can be explained by a triple effect: solution strengthening, grain grinding and high residual compressive stress. The addition of Y indicates a slower growth of the oxide layer on the surface of the coating during the wear test. After the addition of Y, Y ions preferentially separate at the grain boundaries and therefore effectively delay the inward diffusion of oxygen. The addition of Y promotes the formation of dense Al2O3, which is effective in restraining diffusion and therefore protects the coating from oxidative wear.

Background. Postcovid syndrome or Long COVID is a new term introduced into medical practice by WHO after the COVID -19 pandemic. Long COVID affects patients who have recovered from COVID -19. Objectives. The purpose of this work is to understand cognitive deficits caused by COVID-19 from the point of view of neuropsychology and pathophysiology. Data Sources. Literature search was conducted in the following electronic databases: Pubmed, Google.scholar and Scopus databases. 63 articles were selected. Keywords for the literature review included “neuropsychiatry/neuropsychology”, “pathophysiology”, “COVID-19”, “SARS-CoV-2”. Methods. Review and analysis of COVID-19 studies in terms of its relation to the appearance of cognitive deficits in patients. Results. The SARS-CoV-2 virus enters the human body and affects the structures of the brain. Some of the symptoms such as fatigue, shortness of breath, problems with concentration and memory, loss or change of taste and smell, pain in muscles and joints as well as sleep disorders are preserved in post-COVID period and may be explained by the peculiarity of the virus interaction with central nervous system. Neuropsychological analysis of observed disorders based on the theory of three functional blocks of the brain by A. R. Luria helps to identify the affected zones of the functional systems of higher mental functions (HMF). Neuropsychological assessment makes it possible to plan rehabilitation programme or cognitive training, and help doctor in choosing an adequate drug therapy to compensate for cognitive impairment. Conclusions. SARS-CoV-2 causes damage to brain structures such as the brainstem, limbic system, prefrontal cortex and olfactory tract, which explains the observed symptoms. Neuropsychological diagnostics makes it possible to identify the impaired component of the HMF in patients with post-COVID syndrome, to plan an adequate rehabilitation programme, as well as to choose drug therapy.

The effect of reaction gas (nitrogen) pressure on the structural-phase state and properties of vacuum-arc nitride coatings of (TiZrSiY)N system has been studied. On the surface of the coatings, a significant amount of the droplet fraction and solidified macroparticles of the sputtered cathode is observed, which is typical for vacuum-arc condensates obtained from unseparated plasma flows. In all samples, titanium nitride with a cubic fcc lattice is identified. In the coatingobtained at nitrogen pressures 0.08 Pa and 0.2 Pa, the α-Ti phase was determined, and the measured lattice parameter of this phase suggests that it is a solid solution of nitrogen in titanium. The texture coefficient of the multicomponent coating obtained at the highest nitrogen pressure of 0.55 Pa has the highest value of 5.95 compared to others. The Vickers hardness of multicomponent coatings increases depending on the partial pressure of nitrogen from 25.0 GPa to 36.0 GPa. According to the complex of tribo-mechanical parameters (hardness, elastic modulus, elastic strain to failure, friction coefficient etc.), suggested multicomponent (TiZrSiY)N coatings can be very attractive for tribological applications.

Two series of multilayer coatings with different numbers of bilayers (268 and 536, respectively) were synthesised using the cathodic vacuum-arc deposition (CVAD) with the simultaneous sputtering of two different cathodes. The first cathode was made of the multicomponent TiZrSiY material, and the second one was made of technical niobium. The coatings were condensed in a nitrogen atmosphere at a constant negative bias potential applied to the substrate. The resulting coatings have a distinct periodic structure composed of individual layers of (TiZrSiY)N and NbN with the thicknesses determined by the deposition interval (10 or 20 s, respectively). The total thicknesses of the coatings determined by the number of bilayers were 11 and 9 microns, respectively. The formation of polycrystalline TiN and NbN phases with grain size comparable to the size of the layers has been identified for both series of coatings. The layers exhibit a columnar structure growth with a predominant orientation (111). The hardness of the experimental coatings depends on the thickness of the layers and reaches 39.7 GPa for the coating with the smallest layer thickness. The friction coefficient of the obtained coatings varies from 0.512 to 0.498 and also depends on the thickness of the layers. A relatively large value of the friction coefficient is due to high roughness and the presence of a droplet fraction on the surface as well as in the volume of the coatings.

The relevance. The paper presents a technical and economic model of a liquefied hydrogen production complex supplied only by renewable energy. The model compares technical and economic indicators of «green» liquefied hydrogen production in different locations subject to their climate, technical and economic conditions. The unique characteristic of the proposed model is that it considers the main technological processes for hydrogen production, conversion and storage, taking into account the annual hourly profile of possible renewable energy generation and shipping schedule of liquefied hydrogen as a commercial output. Employing the model will be relevant at the stage of pre-feasibility studies devoted to the creation of hydrogen energy productions in regions with high renewable energy potentials and remote from power infrastructure and allow enhancing reasonableness of estimations when taking investment decisions. The main aim: to develop a technical and economic model of such a complex and to test it by estimating the levelized cost of «green» liquid hydrogen for selected locations in Mongolia and Japan. Object: the autonomous complex for production of «green» hydrogen. Methods. The model is based on an optimization problem that determines the level and structure of costs born to produce liquefied hydrogen using solar and wind energy. Results. For verification of the model the comparative estimations for production of 10000 tonnes per year of the liquefied «green» hydrogen were calculated. The costs for locations in Mongolia (east coast of Lake Hubsugul) and Japan (coastal areas of Yamagata Prefecture) amount to $10,8 per kg and $13,4 per kg, respectively.

Хронические нарушения сознания (ХНС) представляют собой синдромы тяжелого поражения центральной нервной системы, приводящие к длительной грубой инвалидизации и требующие значительных усилий по лечению и реабилитации, которые ложатся на медицинские учреждения и на плечи близких пациентов. ХНС развиваются у пациентов после комы и характеризуются наличием бодрствования при полном или практически полном отсутствии признаков осознанного поведения. К ХНС относятся вегетативное состояние (ВС) и состояние минимального сознания (СМС). Также для описания начальных стадий этих состояний используется термин «продленное нарушение сознания» (ПНС). Отдельно выделяют выход из СМС — состояние, которое формируется по мере восстановления когнитивных функций. Диагностика ХНС основывается на многократном структурированном клиническом осмотре с применением специализированных шкал при условии исключения обратимых причин нарушения сознания. Лечение пациентов с ХНС включает в себя поддержание жизненно важных функций, обеспечение оптимального питания и борьбу с типичными осложнениями и сопутствующими состояниями (пролежни, спастичность, боль, пароксизмальная симпатическая гиперактивность и др.). У пациентов с ХНС должна проводиться реабилитация с участием мультидисциплинарной реабилитационной команды в объеме, который определяется проблемами и возможностями конкретного пациента. Наиболее эффективной реабилитация является при условии ее раннего начала. На данный момент однозначных доказательств эффективности каких-либо специфических методов, направленных на восстановление сознания, не получено; изучается ряд соответствующих фармакологических и нефармакологических вмешательств, обязательным условием применения которых является максимально возможная коррекция соматических проблем пациента. Важную роль в ведении пациентов с ХНС играет вовлечение близких пациента, которые, в свою очередь, нуждаются в получении объективной практической информации о состоянии своего родственника и о направлениях реабилитации, а также в психологической помощи.

Ранній неонатальний сепсис, за даними сучасної епідеміології, у 84% випадків має бактеріальну етіологію. За матеріалами останніх конгресів Міжнародного септикологічного форуму (ISF), у тому числі ISF 2021, серед тяжких форм неонатального сепсису превалює колі та клєбсіельозний сепсис, часто пов’язаний з материнською інфекцією. Мета - показати можливості патогенетичного підходу в лікуванні тяжкого колі-клебсіельозного сепсису новонародженого. Наведено досвід лікування дитини з неонатальним сепсисом, пов’язаним із внутрішньоутробною інфекцією, що ускладнився некрозом м’яких тканин майже всієї волосистої поверхні голови. До відділення хірургії новонароджених дитину госпіталізовано з ознаками ранового сепсису, відкритою інфікованою раною всієї волосистої поверхні голови, частково вкритою некротизованим шкірно-волосистим клаптем. Вивчено анамнез захворювання, встановлено тісний зв’язок із внутрішньоутробною колі-інфекцією матері. Дитину обстежено лабораторними (мікробіологічними крові та ранової поверхні, біохімічними - загальні, прокальцитонін, С-реактивний білок, коагулограма, а також імунологічними - Т-, В-лімфоцити, СД-64-крові) та інструментальними (ультразвукове дослідження, комп’ютерна томографія, рентгенологічні) методами. Виділений при некректомії шкірно-волосистий клапоть обстежено гістологічно. На основі результатів досліджень призначено патогенетичну протизапальну терапію, що дала змогу підготовити дитину до оперативних втручань - некректомії та подальшої трансплантації аутошкіри. У лікуванні взяла участь багатопрофільна команда, дитина одужала, повністю відновлено шкірний покрив голови. Висновки. Отримані результати досліджень та позитивний результат лікування показують ефективність патогенетичного підходу до лікування тяжких форм сепсису в новонароджених дітей. Дослідження проведено відповідно до принципів Гельсінської декларації прав людини. На проведення досліджень отримано інформовану згоду батьків дитини. Автори заявляють про відсутність конфлікту інтересів.

Background. The vaccine is the best available instrument to prevent influenza and reduce the risks of major disease complications and mortality. The vaccine effectiveness during the influenza season depends on a number of factors: (1) a person vaccinated (their age and health status); (2) the vaccine formulation; (3) types and subtypes of the circulating viruses; (4) vaccination timeline, as the immune response fades over time. An influenza vaccine can yield different effectiveness in people who have been infected or vaccinated previously and in those who have not been yet exposed to the circulating viruses. At present, trivalent and quadrivalent influenza vaccines are registered and produced in Russia. It allows for vaccination of all social groups, including high-risk populations, and for increasing the number of vaccinated individuals yearly. Russian Federation constantly improves the production of influenza vaccines, introducing new variants of vaccine formulations into national clinical usage. It is thus essential to monitor and analyze the changes in the effectiveness of influenza vaccines every season.Aim of the study. To evaluate of the effectiveness of Russian domestic influenza vaccines during the epidemic season 2019–2020 in St. Petersburg compared to the season 2018–2019.Materials and Methods. 3315 female and male adult participants aged 18 years and older were monitored from October 2019 to March 2020. The group included university students and tutors, researchers, and production and office workers of industrial enterprises. Sovigripp, Grippol Plus, Ultrix, and Ultrix Quadri influenza vaccines were used for immunization.Results and Discussion. In the context of incomplete correspondence between the viruses circulating in Russia and the strains used in the vaccines, the vaccination of the St. Petersburg population during the epidemic season 2019-2020 with Sovigripp, Grippol Plus, Ultrix, and Ultrix Quadri influenza vaccines cumulatively reduced influenza and ARI incidences by half; the total vaccine effectiveness against influenza and ARI amounted to 50.0%. The strongest preventive effect was identified for Grippol Plus, Ultrix, and Ultrix Quadri which demonstrated the total vaccine effectiveness from 70.6% to 75.0%, and their effectiveness against influenza A and B viruses reached from 65.5% to 83.5%.Conclusion. In the context of incomplete correspondence between the viral strains used in the vaccines and the strains circulating in Russia and St. Petersburg during the epidemic season 2019- 2020 and considering the active circulation of non-influenza viruses such as rhinoviruses and adenoviruses, we found a moderate preventive effectiveness of the influenza vaccines during the seasonal epidemic increase in ARI cases. Russian domestic influenza vaccines were shown to have good acceptability, be safe, and non-reactogenic.

Multilayer (TiSi)N/CrN coatings were fabricated through vacuum-arc deposition by applying the arc currents of (100 ÷ 110) A on TiSi cathode and (80 ÷ 90) A on Cr cathode, negative bias potential connected to the substrate holder of –(100 ÷ 200) V and reactive gas pressure of (0.03 ÷ 0.6) Pa. Applying a negative bias voltage on substrates enhanced the ion bombardment effect, which affected the chemical compositions, phase state, mechanical and tribological properties of (TiSi)N/CrN coatings. Obtained results indicated that (TiSi)N/CrN coatings with Si content ranging from 0.53 to 1.02 at. % exhibited a high hardness level of (22.1 ÷ 31.1) GPa accompanied with a high Young’s modulus of (209 ÷ 305) GPa, H/E* level of (0.080 ÷ 0.100), H3/E*2 level of (0.15 ÷ 0.33) GPa, and the friction coefficient of 0.35. Values of critical loads at dynamic indentation, changes in friction coefficient and level of acoustic emission signal evidence the high adhesive strength of (TiSi)N/CrN coatings, which allows recommending them to increase cutting tool performance.

Background. The influenza vaccination coverage has steadily increased in the Russian Federation. The introduction of new domestic influenza vaccines into practice and the study of their effectiveness are of great importance for public health. However, a systematic analysis of the effectiveness of vaccines manufactured and used in Russia in recent years has not been performed. The aim ofthe study was to assess the epidemiological effectiveness of three domestic influenza vaccines in St. Petersburg during the 2018–2019 epidemic season.Material and methods. The organized community of 1892 young students aged 18 to 23 years has been under supervision during the period of time from October 2018 to March 2019. Influenza vaccines Grippol Plus, Sovigripp, and Ultrix were used for vaccination.Results and discussion. Prophylactic vaccination with influenza vaccines Sovigripp, Grippol Plus and Ultrix in the fall of 2018 led to a decrease in the incidence of influenza and other acute respiratory infections (ARI) by a total of 1.6–3.8 times; a decrease in the incidence of influenza by 2.7–7.1 times; the total protective efficacy of vaccines against influenza and ARI was 52.4%, and against influenza, taking into account laboratory correction, 73.3%.Conclusions. Under the conditions of the viruses circulating in Russia and in St. Petersburg in the 2018–2019 epidemic season the strains introduced into the composition of influenza vaccines, domestic influenza vaccines were characterized by good tolerance, were safe, areactogenic and had a pronounced protective effect. If the viruses circulating in Russia and in St. Petersburg in the 2018–2019 epidemic season corresponded to the strains introduced into the composition of influenza vaccines, domestic influenza vaccines, showing good tolerance, safety and low reactogenicity, had a pronounced protective effect.

Data on the study of the efficacy of the tablets of cycloferon, an early inductor of types 1 and 2 interferon, in the treatment of influenza and acute respiratory tract viral infections in adults are presented. The study enrolled 522 patients with moderate influenza of type A (H1N1) verified in 61% of the patients and type A (H3N2) verified in 7.5% of the cases. The patients were randomized with the envelope procedure. In the patients treated with cycloferon the intensity and period of the fever were stopped earlier and averaged from 1.8 to 3 days vs. 5 days in the reference group (symptomatic therapy)/ The improvement signs in the general state ofthe patients treated with cycloferon were noted on the 2nd day. The influenza complication as pneumonia was recorded in 2.2% of the patients treated with cycloferon, whereas in the patients under the symptomatic therapy the complications as bronchitis, pneumonia, angina were stated in 21.4% of the cases. For urgent prophylaxis of the influenza and respiratory tract viral infections (epidemiologic study) a group of 3717 subjects randomized with the table of random numbers was observed. 2080 patients were treated with cycloferon and 1637 patients were under the symptomatic therapy. The results were evaluated by the efficacy index and the protection estimate (T. A. Semenenko, 1991). The total efficacy index and the protection estimate in all the patients of the group were 4.9 and 79.8% respectively. The complicated forms of the disease were recorded in 1.5% of the patients treated with cycloferon and in 10.5 and 11.3% of the patients not treated with cycloferon.

The results of studies of the influence of Y as a reactive element on the properties of TiAlN coatings obtained by the method of vacuum-arc deposition are given. Changes in the structure and properties were analyzed using SEM in combination with EDX, XRD, indentation analysis and wear analysis. It is shown that the presence of Y changes the crystalline phase of the Ti0.6Al0.34Y0.06N coating. It consists of a combination of a cubic NaCl structure (basic phase) and a wurtzite structure (additional phase). In addition, it leads to a small grain size (12 nm) and a nano-columnar structure. The high hardness is partly the result of solution hardening due to the inclusion of larger Y atoms in the TiAlN lattice at the locations of the metal atoms. The reduced grain size of 12 nm also helps to increase the hardness of the coating. The hardness is 31 ± 2.5 GPa, the modulus of elasticity is 394.8 ± 35.8 GPa. The residual stress is approximately three times (-3352 ± 64 MPa) higher than the TiAlN coating (-720 MPa). In addition, a high level of compressive stress contributes to an increase in hardness, since defects responsible for their own compressive stress are an obstacle to dislocation movement. The improved hardness of the experimental coating can be explained by a triple effect: solution strengthening, grain grinding and high residual compressive stress. The addition of Y indicates a slower growth of the oxide layer on the surface of the coating during the wear test. After the addition of Y, Y ions preferentially separate at the grain boundaries and therefore effectively delay the inward diffusion of oxygen. The addition of Y promotes the formation of dense Al2O3, which is effective in restraining diffusion and therefore protects the coating from oxidative wear. [ABSTRACT FROM AUTHOR]

The article reviews the literature on the diagnosis and treatment of primary lymphomas of the central nervous system and describes a case of mental disorder before and after surgery in a patient with lymphoma of the third ventricle. Using an interdisciplinary approach, psychopathological dynamics is analyzed taking into account the structural and functional state of the brain, which allowed to clarify the possible causes of mental disorders and methods of treatment. Acute onset of confusion and headache was associated with disorders of the liquor outflow, due to the localization of the tumor. The reason for the disintegration of consciousness after surgery was brain hypoxia and the instability of connections between cerebral structures associated with it. The peculiarity of the consciousness recovery could be determined by premorbid personal traits.

To certify gas mixtures in the range of low (10-3-10-8 g/m3) mercury concentrations, we have proposed and tested a traceable method for measuring the mass concentration of mercury in gaseous media by inductively coupled plasma mass spectrometry (ICP/MS). The proposed method is based on a scheme that provides for the mass spectrometer calibration for saturated vapors (physical constant) of pure metallic mercury, dosed directly into the carrier gas stream - argon. The undoubted advantage of this method is its applicability to various gases and gas mixtures, which allows you to simulate any matrix medium that affects the measurement results of mercury content when analyzed by other methods. On this basis, «Methods of measuring the mass concentration of mercury in binary gas mixtures by ICP/MS» were developed and certified. The measurement range of mercury mass concentration is from 0,03 to 1000 pg/m3, the relative expanded uncertainty of measurements U- 4 %.

The scientific interest in the investigation of nitride composites as protecting materials in tool and machining industries intensively increases. The good oxidation resistance of CrN single-layer films and high melting point, good chemical and thermal resistance of ZrN compound are motive factors for designing of multilayer composites composed of these metal nitrides. The suggested advantages of ZrN/CrN multilayer coatings as structural materials are the high-temperature resistance, high density and extreme hardness compared to the metal-nitride systems. Experimental ZrN/CrN multilayer coatings were deposited on AISI 321 steel substrates by using a cathodic arc evaporation device equipped with two high-purity metal Cr and Zr targets. Structural, chemical and morphological characteristics together with mechanical properties of multilayer composites were analyzed by X-ray diffraction, scanning electron microscopy, energy-dispersive X-ray spectroscopy and Vickers hardness tester. SEM analysis revealed an increase of roughness and concentration of the droplets on the surface of the coatings when negative bias potential decreased to -70 V. The results of data obtained from the X-ray analysis showed (200) and (111) plane for ZrN and Cr2N phases as the most intense. The peak positions of ZrN were shifted towards lower diffraction angles comparing with bulk values and indicated a decrease of the inter-planar distance and formation of compressive stresses. The calculated lattice strain values in the ZrN were higher than those of the CrN, indicated a greater presence of dislocations and defects in the lattice of ZrN. The averaged crystallite sizes in ZrN and CrN layers were 11-14 and 7-12 nm, respectively. The maximum value of the Vickers microhardness was found to be 6600HV0.01 that is 2.1 and 1.8 times greater than the corresponding values of binary CrN and ZrN coatings.

Введение. Отсутствие единой хирургической тактики лечения атрезии пищевода (АП) с большим диастазом, а также частые неудовлетворительные результаты при использовании существующих методик побуждают к поиску и внедрению нового хирургического подхода к коррекции порока. Цель. Оптимизировать хирургическое лечение АП с большим диастазом и обеспечить сохранение собственного пищевода путем элонгации за счет индукции роста атрезированных сегментов. Материалы и методы. Проанализировано 6 клинических случаев пациентов с АП с большим диастазом. Всем пациентам выполнялась этапная коррекция порока путем элонгации сегментов пищевода тракционными швами с последующим формированием анастомоза. Результаты. Выполнено хирургическое лечение у 6 пациентов с АП с большим диастазом между сегментами с использованием методики индукции роста пищевода с помощью тракционных швов по Фокеру. Длительность тракции составляла 6-19 дней, средняя ежедневная дистанция тракции каждого из сегментов составляла от 2,4 до 4,8 мм. Эффективность роста сегментов контролировалась рентгенографически с помощью положения рентген-контрастных меток на концах сегментов пищевода или эзофагографии. Во всех 6 случаях после использования дозированной этапной тракции наблюдалось удлинение пищевода с уменьшением диастаза между его сегментами до 0-1,0 см, что позволило сформировать анастомоз конец в конец. Во всех случаях восстановлено полноценное вскармливание через рот с сохранением собственного пищевода. Выводы. Методика индукции роста позволяет преодолеть большой диастаз между сегментами атрезированного пищевода, создать условия для формирования анастомоза и сохранить собственный пищевод с восстановлением возрастного перорального питания. Концепция индукции роста пищевода исключает или уменьшает применения кишечных пластик. Процедура Фокера является органосохраняющим методом и является альтернативой операциям с потерей пищевода.

The studies of the structure and properties of nanoscale multilayer coatings of Zr- and Cr-based refractory metals obtained by the vacuum arc cathode deposition are summarized in a brief review of the literature data. A comparative analysis of the microstructure and properties of ZrN/CrN composite coatings depending on the deposition conditions (constant negative potential of the substrate, pulsed high-voltage bias potential, partial pressure, reaction gas velocity) and modulation period for multilayered structure is carried out. General regularities consisting in the presence of the columnar structure and the growth texture are revealed. They show that there is a prevailing (111) orientation for investigated coatings. Conditions for obtaining improved physical, mechanical, and tribological properties of the coatings are determined.