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We study a class of equations in Banach spaces with a Riemann–Liouville-type integro-differential operator with an operator-valued convolution kernel. The properties of \(k\)-resolving operators of such equations are studied and the class \(\mathcal A_{m,K,\chi}\) of linear closed operators is defined such that the belonging to this class is necessary and, in the case of commutation of the operator with the convolution kernel, is sufficient for the existence of analytic in the sector \(k\)-resolving families of operators of the equation under study. Under certain additional conditions on the convolution kernel, we prove theorems on the unique solvability of the nonhomogeneous linear equation of the class under consideration if the nonhomogeneity is continuous in the norm of the graph of the operator from the equation or Hölder continuous. We obtain the theorem on sufficient conditions on an additive perturbation of an operator of the class \(\mathcal A_{m,K,\chi}\) in order that the perturbed operator also belong to such a class. Abstract results are used in the study of initial-boundary value problems for a system of partial differential equations with several fractional Riemann–Liouville derivatives of different orders with respect to time and for an equation with a fractional Prabhakar derivative with respect to time.

We investigated the physicochemical aspects of the gas-phase nanopowder synthesis using a cyclic compression reactor. Compression of precursors (methane, ethylene, acetylene) under conditions close to the adiabatic ones in the atmosphere of buffer monatomic gases (argon, helium, neon) was used. The influence of pressure in the reactor and volumetric ratio of precursor/buffer gas mixture on the composition, morphology, and structure of carbon-containing particles representing the pyrolysis product was studied. Complete pyrolysis was observed for all studied precursors, but under different conditions. Thermal decomposition of methane, having the minimum enthalpy of formation, was observed in an atmosphere with argon content 97.5 % at a peak pressure more than 10 MPa. Helium showed limited possibilities for thermal relaxation under the conditions of fast reactions (< 50 ms). Only acetylene with the maximum enthalpy of formation was decomposed in the atmosphere of helium. The solid reaction products represented black colored powders with a bulk density of 20–30 mg/cm3. The powders were examined by transmission electron microscopy and scanning electron microscopy, Raman scattering and X-ray diffraction analysis. The particles represent globular bulbous structures up to 100 nm in size, either hollow or filled inside. X-ray diffraction analysis showed the presence of a graphite-like structure with crystallite sizes less than 10 nm in all samples. Raman analysis showed mainly sp2 hybridization of carbon. The cyclic compression method demonstrates wide range of opportunities for the pyrolysis of hydrocarbons aiming at the production of a variety of carbon structures, which enables for the fine tuning in terms of the yield of products of the required morphology for practical use.

Aim. To investigate the potential for searching new virulent bacteriophages in the paleontological material extracted from the permafrost zone.Material and methods. The virome structure of the colon content of the wolf pup mummy (Canis lupus) from the late Pleistocene was evaluated by means of shotgun metagenomic sequencing.Results. The study demonstrated the predominance of Myoviridae tailed bacteriophages, including PhiKZ-like phages, in the structure of the virome.Conclusion. The results of the study indicate the possibility of using paleontological material preserved in the ancient Arctic permafrost as a resource for searching and isolating new virulent bacteriophages.

To identify features of the taxonomic composition of the oropharyngeal microbiota of COVID-19 patients with different disease severity.The study group included 156 patients hospitalized with confirmed diagnosis of COVID-19 in the clinical medical center of Yevdokimov Moscow State University of Medicine and Dentistry between April and June 2021. There were 77 patients with mild pneumonia according to CT (CT1) and 79 patients with moderate to severe pneumonia (CT2 and CT3). Oropharyngeal swabs were taken when the patient was admitted to the hospital. Total DNA was isolated from the samples, then V3V4 regions of the 16s rRNA gene were amplified, followed by sequencing using Illumina HiSeq 2500 platform. DADA2 algorithm was used to obtain amplicon sequence variants (ASV).When comparing the microbial composition of the oropharynx of the patients with different forms of pneumonia, we have identified ASVs associated with the development of both mild and severe pneumonia outside hospital treatment. Based on the results obtained, ASVs associated with a lower degree of lung damage belong predominantly to the class of Gram-negative Firmicutes (Negativicutes), to various classes of Proteobacteria, as well as to the order Fusobacteria. In turn, ASVs associated with a greater degree of lung damage belong predominantly to Gram-positive classes of Firmicutes Bacilli and Clostridia. While being hospitalized, patients with severe pneumonia demonstrated negative disease dynamics during treatment significantly more often.We have observed differences in the taxonomic composition of the oropharyngeal microbiota in patients with different forms of pneumonia developed outside hospital treatment against COVID-19. Such differences might be due to the presumed barrier function of the oropharyngeal microbiota, which reduces the risk of virus titer increase.Цель. Выявить особенности таксономического состава микробиоты ротоглотки пациентов с COVID-19 с различной степенью тяжести заболевания. Материалы и методы. Исследуемая группа пациентов включала в себя 156 пациентов, госпитализированных с подтвержденным диагнозом COVID-19 в клинический медицинский центр ФГБОУ ВО МГМСУ им. А.И. Евдокимова в период с апреля по июнь 2021 г., из них 77 пациентов с легкой формой пневмонии по данным компьютерной томографии (КТ) КТ-1 и 79 пациентов с умеренной и среднетяжелой формой пневмонии (КТ-2 и КТ-3). Отбор мазков из ротоглотки осуществляли при поступлении пациента в стационар. Из образцов выделяли тотальную ДНК, затем производили амплификацию V3V4 регионов гена 16s рРНК с последующим секвенированием на приборе Illumina HiSeq 2500. Для получения вариантов ампликонных последовательностей (ASV) использовался алгоритм DADA2. Результаты. При сравнении микробного состава ротоглотки пациентов с различной формой пневмонии обнаружены ASV, ассоциированные с развитием как легкой, так и тяжелой форм пневмонии вне лечения в стационаре. Исходя из полученных результатов можно заключить, что ASV, ассоциированные с меньшей степенью поражения легких, в основном относятся к классу грамотрицательных фирмикут (Negativicutes), к различным классам протеобактерий, а также к порядку Fusobacteria. В свою очередь ASV, ассоциированные с большей степенью поражения легких, относятся преимущественно к грамположительным фирмикутам классов Bacilli и Clostridia. При нахождении в стационаре пациенты с тяжелой формой пневмонии достоверно чаще демонстрировали отрицательную динамику на фоне проводимых терапевтических мероприятий. Заключение. Различия в таксономическом составе микробиоты ротоглотки, наблюдающиеся у пациентов с различной формой пневмонии, развившейся вне стационарного лечения на фоне COVID-19, могут быть связаны с предположительной барьерной функцией микробиоты ротоглотки, которая позволяет снизить риск нарастания титра вируса.

The work presents the biological characteristics of the females of the Amur sturgeon caught in the Amur River: indicators of the length and body weight of females, the mass and stages of maturity of their gonads, the dimensional mass characteristic of oocytes, indicators of individual absolute and relative fertility. The results of histological examination of gonads are presented. Degenerative changes in the structure of the reproductive system were noted, reducing the effectiveness of natural reproduction.

The article presents the results of an audit of the corporate students needs in professional communication skills in foreign languages, viz. English. Conducted in 2017 and 2022 in Krasnodar among employees of five commercial organizations and a state university, the study was aimed at identifying factors of reduction in efficiency of teaching foreign languages in Russia (stop factors), as well as finding ways to avoid them (push factors). Data analysis revealed an obvious pragmatic gap between the process of learning a foreign (English) language by respondents at the school or university stage and the outcome of such learning in terms of their inability to apply gained knowledge and skills to various communicative situations at workplace. Conclusion was made that the traditional language education policy in Russia requires immediate modernization in accordance with international standards as well as incorporation of the best grading and assessment practices such as CEFR.

The concept of a β-integrated resolving function for a linear equation with a Gerasimov–Caputo fractional derivative is introduced into consideration. A number of properties of such functions are proved, and conditions for the solvability of the Cauchy problem to linear homogeneous and inhomogeneous equations are found in the case of the existence of a β-integrated resolving function. The necessary and sufficient conditions for the existence of such a function in terms of estimates on the resolvent of its generator are obtained. The example of a β-integrated resolving function for the Schrödinger equation is given. Thus, the paper discusses some aspects of the symmetry of the concepts of integrability and differentiability. Namely, it is shown that, in the absence of a sufficiently differentiable resolving function for a fractional differential equation, the problem of the existence of a solution can be solved by an integrated resolving function of the equation.

The unique solvability in the sense of classical solutions for nonlinear inverse problems to differential equations, solved for the oldest Dzhrbashyan–Nersesyan fractional derivative, is studied. The linear part of the equation contains a bounded operator, a continuous nonlinear operator that depends on lower-order Dzhrbashyan–Nersesyan derivatives, and an unknown element. The inverse problem is given by an equation, special initial value conditions for lower Dzhrbashyan–Nersesyan derivatives, and an overdetermination condition, which is defined by a linear continuous operator. Applying the fixed-point method for contraction mapping a theorem on the existence of a local unique solution is proved under the condition of local Lipschitz continuity of the nonlinear mapping. Analogous nonlocal results were obtained for the case of the nonlocally Lipschitz continuous nonlinear operator in the equation. The obtained results for the problem in arbitrary Banach spaces were used for the research of nonlinear inverse problems with time-dependent unknown coefficients at lower-order Dzhrbashyan–Nersesyan time-fractional derivatives for integro-differential equations and for a linearized system of dynamics of fractional Kelvin–Voigt viscoelastic media.

The microbiota of the respiratory tract remains a relatively poorly studied subject. At the same time, it is involved in modulating the immune response to infectious agents in the host organism, just like the intestinal microbiota. A relationship between the composition of the respiratory microbiota and the likelihood of development and the severity of COVID-19 may be assumed. In this study, we applied the 16S rRNA metagenomic sequencing to analyze the oropharyngeal swabs from 120 COVID-19 patients collected during the first and the second waves of the COVID-19 epidemic in Russia. Differential abundance analysis with respect to comorbidities suggested association of Neisseria oralis, Neisseria mucosa, unidentified Veillonella spp., Lautropia mirabilis species with more severe lung damage, and Streptococcus salivarius, Capnocytophaga sputigena and Haemophilus parahaemolyticus with a milder course of the disease. We hypothesize that the latter bacteria (or some of them) might be beneficial for the respiratory tract and might be able to alleviate the course of the COVID-19 disease.

The fractional powers of generators for analytic operator semigroups are used for the proof of the existence and uniqueness of a solution of the Cauchy problem to a first order semilinear equation in a Banach space. Here, we use an analogous construction of fractional powers Aγ for an operator A such that −A generates analytic resolving families of operators for a fractional order equation. Under the condition of local Lipschitz continuity with respect to the graph norm of Aγ for some γ∈(0,1) of a nonlinear operator, we prove the local unique solvability of the Cauchy problem to a fractional order quasilinear equation in a Banach space with several Gerasimov–Caputo fractional derivatives in the nonlinear part. An analogous nonlocal Lipschitz condition is used to obtain a theorem of the nonlocal unique solvability of the Cauchy problem. Abstract results are applied to study an initial-boundary value problem for a time-fractional order nonlinear diffusion equation.

In this study, we put together a list of potentially the most beneficial bacteria that were associated with a responsiveness to melanoma immunotherapy. Another important result of this study is the list of functional biomarkers of responsiveness to immunotherapy, which are dispersed among different bacterial species.

In this study, we present the growth of monolayer MoS2 (molybdenum disulfide) film. Mo (molybdenum) film was formed on a sapphire substrate through e-beam evaporation, and triangular MoS2 film was grown by direct sulfurization. First, the growth of MoS2 was observed under an optical microscope. The number of MoS2 layers was analyzed by Raman spectrum, atomic force microscope (AFM), and photoluminescence spectroscopy (PL) measurement. Different sapphire substrate regions have different growth conditions of MoS2. The growth of MoS2 is optimized by controlling the amount and location of precursors, adjusting the appropriate growing temperature and time, and establishing proper ventilation. Experimental results show the successful growth of a large-area single-layer MoS2 on a sapphire substrate through direct sulfurization under a suitable environment. The thickness of the MoS2 film determined by AFM measurement is about 0.73 nm. The peak difference between the Raman measurement shift of 386 and 405 cm−1 is 19.1 cm−1, and the peak of PL measurement is about 677 nm, which is converted into energy of 1.83 eV, which is the size of the direct energy gap of the MoS2 thin film. The results verify the distribution of the number of grown layers. Based on the observation of the optical microscope (OM) images, MoS2 continuously grows from a single layer of discretely distributed triangular single-crystal grains into a single-layer large-area MoS2 film. This work provides a reference for growing MoS2 in a large area. We expect to apply this structure to various heterojunctions, sensors, solar cells, and thin-film transistors.

The OBJECTIVE was to improve the effectiveness of prevention of thrombohemorrhagic disorders in patients with calculous cholecystitis and obstructive jaundice.METHODS AND MATERIALS. The clinic examined 537 patients operated on for obstructive jaundice. From 2010 to 2015, the prevention of thrombohemorrhagic complications consisted in the determination of risk factors, elastic compression of the lower extremities and the appointment of anticoagulants (1st comparative group). Since 2015, all medical measures have also been carried out taking into account the stages of obstructive jaundice (2nd study group).RESULTS. When comparing the results, the number of subhepatic abscessed hematomas decreased from 4 (1.6 %) patients in the first group to 2 (0.8 %) in the second, the number of gastric bleedings-from 6 (2.4 %) to 3 (1.2 %), metrorrhagia – from 3 (1.2 %) to 1 (0.4 %), pancreatic necrosis – from 8 (3.2 %) to 5 (1.9 %), pulmonary embolism – from 7 (2.8 %) to 5 (2.0 %), the number of strokes and transient disorders of cerebral circulation – from 5 (2.0 %) to 3 (1.2 %), the number of cardiac arrhythmias in the form of atrial fibrillation-from 3 (1.2 %) to 2 (0.8 %). The incidence of myocardial infarction decreased from 5 (2.0 %) patients to 3 (1.2 %), and the incidence of mesenteric vascular thrombosis decreased from 3 (1.2 %) to 1 (0.4 %). In group 1, 2 (0.8 %) patients had hemobilia.CONCLUSION. In addition to protocols and standards, the prevention of thrombohemorrhagic complications should take into account the stages of obstructive jaundice. During the period of cholestasis, the prevention of thrombohemorrhagic complications should be used in the same volume as in the absence of jaundice. In hepatocytolysis, it should be performed using the CHA2DS2-VASc scale with the HEMORR2HAGESscale as a safety net. In cholangitis, on the contrary, the main role is assigned to the HEMORR2HAGESscale.

Background. A crucial role in the development of cancer is played by the tumor microenvironment (TM) – a microenvironment that is formed as a result of the interaction between the tumor tissue and macroorganism cells. The concentration of TM cytokines in the blood varies depending on the activity of the tumor and the presence of a metastatic process. It is advisable to study the existing mediator imbalance of TM, its characteristic features in the process of tumor development for the diagnosis and prognosis of the tumor process.The aim. To identify markers of tumor progression in the study of tissue and serum cytokines in women diagnosed with breast cancer.Materials and methods. The object of the study is blood serum cytokines and tumor supernatants (MCP-1, VEGF, TNF-α, IFN-γ, TGF-β1, G-CSF, GM-CSF). The study involved 80 patients with breast cancer aged 50–69 years and 26 practically healthy women aged 41 to 62 years. A standard examination of women was conducted; a cytokine profile study was conducted before the appointment of therapy. To study the cytokine profile at the tissue level, tumor biopsies (n = 30) and biopsies of unchanged breast tissue (n = 6) were incubated to determine the production of MCP-1, VEGF, TNF-α, IFN-γ, TGF-β1, G-CSF, GM-CSF.Results. There was a moderate positive correlation between the stage of the disease and the level of TGF-β1, MCP-1 blood serum, a weak one – with G-CSF. In the incubated tumor tissue, a high positive correlation of cytokines on the stage of the disease is observed in growth factors: VEGF (R = 0.79; p > 0.05) and TGF-β1 (R = 0.61; p > 0.05).Conclusion. The study revealed the characteristic features of the cytokine profile of blood serum and tumor tissue in breast cancer at local and widespread stages. The revealed differences in the level of cytokines should be used as additional diagnostic indicators of the degree of activity and prevalence of the tumor process.