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In a retrospective study, we evaluated factors associated with the early development of septic shock in patients with severe COVID-19.We collected medical records of the intensive care unit patients submitted by the local COVID-19 hospitals across Russia to the Federal Center for the Critical Care at the Sechenov First Moscow State Medical University (Sechenov University). Septic shock in crticially ill patients requiring mechanical ventilation was defined as a need in vasopressors to maintain blood pressure.We studied 1078 patients with severe COVID-19 who were admitted to the intensive care units for respiratory support. There were 611 males and 467 females. The mean age was 61.013.7 years. Five hundred twenty five medical records (48.7%) were received from the Moscow hospitals, 159 (14.7%) from the Moscow region, and 394 (36.5%) from the hospitals located in 58 regions of the Russian Federation. In 613 (56.9%) patients, diagnosis of SARS-CoV-2 infection was confirmed by PCR, and in the other cases it was established on the basis of the clinical picture and the results of the chest CT scan. Septic shock developed in 214 (19.9%) of 1078 patients. In the logistic regression model, the risk of septic shock in patients older than 50 years was higher than in patients of a younger age (OR 2.34; 95% CI 1.533.67; p0.0001). In patients with more severe SARS-CoV-2 infection, there was an increase in the prevalence of cardiovascular diseases, including coronary heart disease and atrial fibrillation, type 2 diabetes and malignant tumors. The risk of septic shock in patients with three or more concomitant diseases was higher than in patients without any concomitant chronic diseases (OR 1.76; 95% CI 1.762.70).The risk of septic shock in patients with acute respiratory distress syndrome induced by SARS-CoV-2 is higher in patients older than 50 years with concomitant diseases, although a severe course of the disease is also possible in younger patients without any concomitant disorders.Цель. Анализ факторов, ассоциированных с ранним развитием септического шока у больных с тяжелым течением COVID-19. Материалы и методы. В исследование включены данные всех пациентов, проконсультированных до 1 мая 2020 г. на базе Федерального дистанционного консультативного центра анестезиологии и реаниматологии на базе ФГАОУ ВО Первый МГМУ им. И.М. Сеченова (Сеченовский Университет). Критерием септического шока считали снижение артериального давления, требовавшее введения вазопрессорных средств. Результаты. В исследование включены 1078 пациентов, 611 (56,7%) мужчин и 467 (43,3%) женщин. Средний возраст составил 61,013,7 года; 525 (48,7%) заявок на консультацию получены из стационаров Москвы, 159 (14,7%) Московской области, 394 (36,5%) лечебных учреждений в 58 регионах Российской Федерации. У 613 (56,9%) больных диагноз SARS-CoV-2-инфекции подтвержден с помощью полимеразной цепной реакции, а в остальных случаях установлен на основании клинической картины и результатов компьютерной томографии органов грудной клетки. Развитие септического шока отмечено у 214 (19,9%) из 1078 больных. В логистической регрессионной модели риск его развития у пациентов старше 50 лет выше, чем у больных более молодого возраста (отношение шансов 2,34; 95% доверительный интервал 1,533,67; р0,0001). У пациентов с более тяжелым течением SARS-CoV-2 отмечалось увеличение частоты сердечно-сосудистых заболеваний в целом, ишемической болезни сердца, фибрилляции предсердий, сахарного диабета 2-го типа, частота злокачественных опухолей выше. Риск развития септического шока у пациентов с тремя и более сопутствующими заболеваниями оказался выше, чем у пациентов без сопутствующих болезней (отношение шансов 1,76; 95% доверительный интервал 1,762,70). Заключение. Риск развития септического шока у пациентов с острым респираторным дистресс-синдромом, вызванным SARS-CoV-2, выше у пациентов старше 50 лет, страдающих несколькими сопутствующими заболеваниями, хотя тяжелое течение заболевания возможно и у более молодых людей без какой-либо сопутствующей патологии.

A method of thermal dissociation of DNA–protein conjugates was developed for the selection of aptamers to human alpha-fetoprotein. The method is based on the identification of the DNA oligonucleotides from the combinatorial DNA libraries with the highest specificity to targets, which remained within the conjugate after two stages: a) washing of unbound sequences; and b) removal of the sequences bound to the DNA but displaying a low affinity to it. The undestroyed most stable complexes were subjected to the thermal dissociation with the involvement of the corresponding oligonucleotides in the next rounds of selection. A comparison of the proposed method with the standard washing demonstrated a more intensive enrichment of the library. Due to the tighter conditions for washing of the target-bound DNA oligonucleotides the use of thermal dissociation can increase the efficiency of selection of highly specific aptamers to their molecular targets.

The substrate efficiency of modified derivatives of 2'-deoxyuridine-(mod-dUTP) and 2'-deoxycytidine-5'-triphosphates (mod-dCTP) was studied in the regime of simultaneous incorporation using the primer elongation reaction (PEX) and PCR with complete replacement of natural deoxytimidine (dT) and deoxycytidine (dC). Polymerases with missing 3'–5' exonuclease activity were used: Taq and Vent (exo-), as well as natural and constructed DNA templates. DNA fragments modified simultaneously by two types of nucleotides with similar and different functional groups were obtained. Research is important for obtaining aptamers with extended properties.

The kinetics of PCR amplification has been studied using fluorescently labeled zwitterionic deoxyuridine triphosphates that contain different fluorophores linkers of different lengths between the fluorophore and nitrogenous base. The concentration dependence of the modified substrate on the yield of the PCR product has been studied. Taq and Vent (exo–) DNA polymerases without 3'-5' exonuclease activity have been used for amplification, and the subsequent hybridization analysis of amplification products has been performed. Hydrophobicity and spatial size of the fluorophore have been found to affect inhibition of polymerases in PCR, while the length of the linker between the fluorophore and heterocyclic base has a significant impact on the substrate properties of the labeled deoxyuridine derivatives, i.e., on their incorporation in the PCR product. Electroneutral derivatives of deoxyuridine triphosphate with an average linker length have appeared to be most effective in PCR and subsequent microarray hybridization analysis. The studied fluor-dUTP are suitable for the incorporation of labels in PCR products using Taq and Vent (exo–) DNA polymerases in the subsequent hybridization analysis.

The substrate properties of nitrogen-base modified derivatives of purine and pyrimidine deoxynucleoside triphosphates during their simultaneous pairwise insertion into the growing DNA strand have been studied. Modified nucleotides were introduced using real-time PCR and the primer extension reaction; in one reaction, derivatives with both different and similar functional substituents were used. Genomic bacterial DNA, specially constructed synthetic DNA fragments, and SELEX libraries were used as templates. The reactions were performed using DNA polymerases with no 3'-5' correcting exonuclease activity: Taq, Vent (exo-), DeepVent (exo-), and KOD XL. It was shown that the substrate efficiency is affected by both the size of the substituent group and the chemical nature of deoxynucleoside triphosphate. The effectiveness varies significantly depending on the polymerase used. The most effective of the studied substrates are pyrimidine deoxynucleoside triphosphates in combination with Vent (exo-) DNA polymerase. DNAs modified by pairs of dissimilar nucleotides (dU + dC, dU + dA, dC + dA) with similar and different functional substituents were obtained.

The use of water energy is an alternative energy source. Water can have both thermal energy for storing solar energy, and mechanical energy created by kinetic and potential energy of the flow. The analysis of the market of equipment for the use of water energy has shown the possibility of using heat pumps, ram pumps and hydro-power equipment, while the advantage in the field of application of such installations remains on the side of foreign manufacturers. Comparison of the heat pump market in Russia and abroad allowed us to conclude about the advantage of foreign heat pump installations: they have a higher efficiency and a larger power range. Russian manufacturers are improving their equipment more and more every year, while producing less expensive installations. Despite the existing development and production of hydro ram pump installations in different countries of the world, their production is very limited, which may be due to the low information content of potential consumers about the capabilities of ram pump installations and manufactured model ranges. Analysis of the market of hydroelectric equipment showed the availability of equipment for different costs and head, microelectric power plants are produced mainly by foreign manufacturers.

The purpose of this work was to evaluate the antimicrobial activity of povidone-iodine solution as a photosensitizer and effective optical range of laser activation identification in vitro. Materials and Methods. As the test cultures reference strains of Candida albicans ATCC 885-653, Staphylococcus epidermidis ATCC 14990, Escherichia coli ATCC 25992, Pseudomonas aeruginosa ATCC 27853, Enterococcus faecalis ATCC 6783 were used. 10 % povidone-iodine solution was added to Petri dishes with the microorganisms on agar and was left in situ for 60 seconds. Fifteen test Petri dishes were irradiated using the remote handle VRV4 λ = 658 nm (Test 1), the other fifteen – with the handle VRIP1 λ = 810 nm (Test 2). Four controls were carried out: the first control (C1) – Petri dishes with inoculated culture without the povidone-iodine solution and laser irradiation influence. The second control (C2) – the photosensitizer was not irradiated. The third control (C3) – it was the irradiation by wavelength 658 nm without chromatophore using. The fourth control (C4) – it was the irradiation by wavelength 810 nm without chromatophore using. Results. The obtained data have shown that povidone-iodine solution was activated in the infrared optical range, as evidenced by the complete absence of test microorganisms growth in Petri dishes “Test 2”. It was found out a reliable decrease in the number of microorganisms colonies in the Petri dishes “Test 1”, but it was achieved by the povidone-iodine antimicrobial activity, rather than by laser activation. This is confirmed by the fact that the number of microorganisms colonies in the Petri dishes ”Test 1” was not statistically different from the number of colonies in the second control group where povidone-iodine solution was not irradiated. Conclusions. It has been proved that the photosensitizer 10% povidone-iodine solution was activated by 810-nm wavelength laser irradiation in the infrared optical range. There had been no growth of microorganisms in nutrient media in test plates compared to the control.

Phase-pure orthorhombic compositions at a Ln/Mo ratio ∼ 5.2-5.7 (Ln = Gd, Dy, Ho) have been obtained for the first time by prolonged (40-160 h) heat treatment of mechanically activated 5Ln2O3 + 2MoO3 (Ln = Gd, Dy, Ho) oxide mixtures at 1200 °C. Although the starting Ln : Mo ratio was 5 : 1 (Ln10Mo2O21 (Ln = Dy, Ho)), it changed slightly in the final product due to the volatility of molybdenum oxide at 1200 °C (40-160 h) (ICP-MS analysis). Brief high-temperature firing (1600 °C, 3 h) of 5Ln2O3 + 2MoO3 (Ln = Gd, Dy, Ho) oxide mixtures leads to the formation of phase-pure fluorites with compositions close to Ln10Mo2O21 (Ln = Gd, Dy, Ho). Gd10Mo2O21 molybdate seems to undergo an order-disorder (orthorhombic-fluorite) phase transition in the range of 1200-1600 °C. For the first time, using the neutron diffraction method, it was shown that low-temperature phases with a Ln/Mo ratio ∼ 5.2-5.7 (Ln = Gd, Dy, Ho) have an orthorhombic structure rather than a tetragonal structure. Proton contribution to the total conductivity of Ln10Mo2O21 (Ln = Gd, Dy, Ho) fluorites and gadolinium and dysprosium orthorhombic phases in a wet atmosphere was observed for the first time. In both orthorhombic and fluorite phases, the total conductivity in wet air decreases with decreasing lanthanide ionic radii. In a wide temperature range, the compounds under study exhibit paramagnetic behaviour. However, the orthorhombic phases of Dy and Ho compounds reach the antiferromagnetic state at 2.4 K and 2.6 K, respectively.

Given the high prevalence of dental caries, it is important to find new means and methods of prevention. At present preparations of natural origin, such as lecithin and calcium citrate, are widely used. The aim was to study the lecithin-calcium complex effect on the oral fluid biochemical parameters of individuals with multiple dental caries. Materials and methods. 85 KhNMU Dental Faculty students-volunteers were examined. Groups of participants were formed depending on the dental caries intensity level index value for the oral fluid biochemical parameters determination (degree of oral dysbiosis, antioxidant-prooxidant index) in patients before and after the start of the lecithin-calcium complex treatment course. Results. In persons with multiple dental caries the degree of dysbiosis is 3 times higher than normal, the concentration of calcium decreases by 1.5 times and the antioxidant-prooxidant index reduces by 2 times. After lecithin-calcium complex treatment course the dysbiosis degree decreases almost by 8 times, the concentration of calcium and API return to normal. This indicates the ability of the lecithin-calcium complex to regulate the oral cavity microbiocenosis and restore antioxidant-prooxidant indices. Conclusions. In patients with multiple dental caries the phenomena of the oral cavity dysbiosis, a decrease in the protective antioxidant system level and a decrease in the oral fluid calcium concentration are observed. The lecithin-calcium complex intake during the month completely eliminated the phenomenon of dysbiosis in the oral cavity, increased the antioxidant-prooxidant system level and the oral fluid calcium concentration to normal.

Purpose. To evaluate the clinical outcomes of intracorneal ring segments (ICRS) implantation and femtosecond laserassisted ICRS implantation to correct the residual astigmatism in post-PKP patients with keratoconus.Material and methods. The study evaluated 28 eyes with residual astigmatism in post-PKP patients with keratoconus. Preop and post-op examination included: refractometry, uncorrected visual acuity (UCVA) and best corrected visual acuity (BCVA), corneal topography, pachymetry, con-focal microscopy. The ICRS was performed in 15 cases (group 1), femtosecond laser-assisted ICRS was performed in 13 cases (group 2).Results. Patients were examined 1, 3 and 6 month after the surgery. The results 3 month after the surgery in the group 1: the mean UCVA improved from 0.13±0.14 to 0.39±0.14, the mean BCVA – from 0.49±0.28 to 0.68±0.1, the mean astigmatism decreased from 8.21±2.21D to 3.20±0.74D, the mean maximum K value decreased from 49.00±2.30D to 44.38±1.90D, the mean minimum K value was 40.82±2.42D preoperatively and 41.18±2.06D postoperatively. The results 3 month after the surgery in the group 2: the mean UCVA improved from 0.09±0.05 to 0.44±0.17, the mean BCVA – from 0.42±0.30 to 0.64±0.17, the mean astigmatism decreased from 7.50±2.47D to 3.16±1.53D, the mean maximum K value decreased from 47.71±2.39D to 43.83±2.73D, the mean minimum K value was 40.29±2.68D preoperatively and 40.67±2.10D postoperatively. At 6 months postoperatively there was no significant difference in relation to the 3-month outcomes.Conclusion. The implantation of ICRS may be an effective procedure for the residual astigmatism correction in post- PKP patients with keratoconus with good visual, refractive and topographic outcomes. The use of the femtosecond laserassistance may provide the ICRS implantation more safe and accurate.

Several families of isoconic motions of a heavy nonautonomous gyrostat with a fixed point are analyzed. Assuming that the conditions for the existence of a generalized Steklov solution are satisfied, we indicate the explicit time dependence of the main variables and analytically study the fixed hodographs of the angular velocity ω, the total angular momentum K of the system, and the center of mass position vector. The time dependence of the angle betweenKand ω is written out and examined. We obtain restrictions on the values of the nutation and proper rotation angles.

The article shows the problem of energy shortage and justifies the necessity of energy-saving activities to be applied in the lighting of buildings. The analysis of solar radiation throughout the year and the length of daylight availability in Chelyabinsk region is made. Based on the analysis of designs and technical characteristics of solar optical fibers their use in newly constructed buildings and social facilities is justified, disclosing the terms of using solar optical fibers in the Urals conditions. The data on the changes of the natural lighting in the room, depending on the time of the day, cloudiness, and the location of the buildings to the cardinal points is produced, the expediency of the combined lighting systems “solar optical fiber+ light-emitting diode” application, which will significantly reduce the lighting costs, is illustrated.

The greatest energy-saving effect in lighting systems can be achieved by the reduction of the operation time of the artificial light sources using natural light. As such a source, one can use modern light transmitting system — solar light guide, which allows sunlight to be delivers deliver to any spot of the room, regardless of the number of storeys, and also provides a uniform natural light. The important factors that affect the efficiency of the use of the solar light guide are light and climatic characteristics of the region. The estimation of energy efficiency of the solar light guide application in conjunction with LED lamps provide illumination at insufficient lighting from the solar light guide in the morning — evening hours, during periods of cloud and depending on the time of the year is presented. The automatic control of the artificial light source light flux increases the energy efficiency of lighting system under consideration by 29.5% in the clouds and by 60.5% on a clear sunny day. The estimation of energy efficiency in the changes of the axis angle incline depending on the latitude of the region to use this lighting system (for example, Chelyabinsk) is shown. The highest efficiency can be achieved with the solar light guide axis incline at 20-25 degrees.

The crystal structure and magnetic properties of the (La0.3Sr0.7)0.5Ca0.5FeO3 solid solution with a perovskite structure have been investigated. The solid solution has been synthesized according to the high-pressure technique. The unit cell parameters have been refined using the Rietveld full-profile analysis under the assumption of the single-phase crystalline state and the two-phase model corresponding to the parent compositions. It follows from the calculations that the best agreement between the experimental data and the theoretical curve is observed for the two-phase model. The measurement of the magnetic properties also indicates the coexistence of two magnetic phases.

International audience; The manganite CaCu3Mn4O12 doped by 119Sn atoms (about 1 at % with respect to Mn atoms) is studied by Mössbauer spectroscopy. The introduction of diamagnetic tin atoms is found not to affect the structure of the manganite. Tetravalent tin atoms are shown to substitute for the isovalent manganese atoms that are located in an octahedral oxygen surrounding. The cluster method of molecular orbitals is used to calculate the contributions of Mn4+ and Cu2+ cations that belong to different structural sublattices to the hyperfine magnetic field at 119Sn nuclei (H Sn = 105 kOe at T = 77 K). These partial contributions are analyzed, and the intrasublattice Mn4+-O-Mn4+ exchange interactions are found to play a significant role in the formation of the magnetic structure of the manganite.

The physical properties of perovskites of the type AC3B4O12, whose structure derives from simple perovskites ABO3, are reviewed. The A position is subject to strong structural distortions and splits into two new positions A and C. In the structure of AC3B4O12 vacancies and any cations with a large radius, irrespective of their charge state, can be present in the icosahedral environment of A: Na+, Cd2+, Ca2+, Sr2+, Y3+, Ln3+, and Nd4+. The C position in the square environment of oxygen can be occupied only by the Jahn–Teller cations Cu2+ and Mn3+. Transition and nontransition metal ions—Mn3+, Fe3+, Al3+, Cr3+, Ti4+, Mn4+, Ge4+, Ru4+, Ir4+, Ta5+, Nb5+, Ta5+, Sb5+—can occupy the B position in an octahedral environment. Some members of the family of complex perovskites possess properties which are characteristic for systems with heavy fermions; collinear and noncollinear magnetic structures with high ordering temperatures occur in these materials; tunneling magnetoresistance and high permittivity are observed...

The review concerns the potentialities of chemically induced dynamic nuclear polarization technique (a spin chemistry method) in studies of elementary processes with participation of short-lived organogermanium species, viz., dimethylgermylene and tetramethyldigermene. The photogeneration and trapping mechanisms of the species in the presence and in the absence of various trapping agents in solutions are considered.

Photolysis of 7,8-digermabicyclo[2.2.2]octadiene (I) was studied by means of 1H-CIDNP and laser pulse photolysis techniques. It was found that photodecomposition of I occurs via germanium-centered 1,6-biradical species. 1,4-Diphenylnaphthalene and tetramethyldigermene are the primary products of the photolytic reaction.

Complexation of paramagnetic intermediates formed in the photolysis of 7,7-dimethyl-1,4,5,6-tetraphenyl-2,3-benzo-7-silanorbornadiene withn-donors (PPh3, O2) was studied by spin chemistry methods.

The influence of an external magnetic field on the yield of photo-decomposition products of 7,7′-dimethyl-7-silanorbornadiene derivative has been detected in laser pulse photolysis experiments. The observations of magnetic field effects alterations in the presence of scavengers, O 2 and PPh 3 , in combination with 1 H-CIDNP data form the basis for the identification of the structure of paramagnetic intermediates involved in the process. It has been shown that magnetic field effects originate in biradical intermediates. These species result from both endocyclic SiC bond cleavage in the initial compound and the reaction of dimethylsilylene (in a singlet or a triplet excited state) with starting 7-silanorbornadiene. To explain the influence of O 2 upon the magnetic field effects, the reversible formation of oxygen complex with biradical species has been suggested.

Using the "break-junction" technique we prepared and studied superconductor - constriction - superconductor nanocontacts in polycrystalline samples of Fe-based superconductors CeO$_{0.88}$F$_{0.12}$FeAs (Ce-1111; $T_C^{\rm bulk} = 41 \pm 1 K$), LaO$_{0.9}$F$_{0.1}$FeAs (La-1111; $T_C^{\rm bulk} = 28 \pm 1 K$), and FeSe ($T_C^{\rm bulk} = 12 \pm 1 K$). We detected two subharmonic gap structures related with multiple Andreev reflections, indicating the presence of two superconducting gaps with the BCS-ratios $2\Delta_L/k_BT_C = 4.2 \div 5.9$ and $2\Delta_S/k_BT_C\sim 1 \ll 3.52$, respectively. Temperature dependences of the two gaps $\Delta_{L,S}(T)$ in FeSe indicate a $k$-space proximity effect between two superconducting condensates. For the studied iron-based superconductors we found a linear relation between the gap $\Delta_L$ and magnetic resonance energy, $E_{\rm res} \approx 2\Delta_L$., Comment: 6 pages, 7 figures. Proceedings of FPS'11 conference

The magnetic susceptibility χ of FeTe(x) compounds (x approximately 1.0) was studied under hydrostatic pressure up to 2 kbar at fixed temperatures of 55, 78 and 300 K. Measurements were taken both for polycrystalline and single crystalline samples. At ambient pressure, with decreasing temperature a drastic drop in χ(T) was confirmed at T approximately 70 K, which appears to be closely related to antiferromagnetic ordering. The obtained results have revealed a puzzling growth of susceptibility under pressure, and this effect is enhanced by lowering the temperature. To shed light on the pressure effects in the magnetic properties of FeTe, ab initio calculations of its volume dependent band structure and the exchange enhanced paramagnetic susceptibility were performed within the local spin density approximation.