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The simplest transformation model of the dynamic deformation along the length of a rod-strip consisting of two segments was constructed. The model is based on the classical geometrically linear Kirchhoff–Love model for the unfixed segment, while the fixed segment of finite length is assumed to be connected to a rigid and immovable support element through elastic interlayers. On the fixed segment, the deflections of the rod and interlayers were considered zero. For axial displacements within the thicknesses of the rod and interlayers, approximations were adopted according to S.P. Timoshenko’s shear model, subject to the conditions of continuity at the points where they connect to each other and immobility at the points where the interlayers connect to the support element. The conditions for kinematic coupling of the unfixed and fixed segments of the rod were formulated. Taking them into account and using the D’Alembert–Lagrange variational principle, the equations of motion and boundary conditions for the considered segments were derived, and the conditions for force coupling of the segments were obtained. With the help of the derived equations, exact analytical solutions of the problems of free and forced harmonic vibrations of the rod of the studied type were found. These solutions were employed in the numerical experiments to determine the natural modes and frequencies of bending vibrations, as well as the dynamic response during the resonant vibrations of the rod-strip made of a unidirectional fibrous composite based on ELUR-P carbon tape and XT-118 binder. The findings show a significant transformation of transverse shear stresses when passing through the boundary from the unfixed segment of the rod to the fixed one, as well as their pronounced localization in the region of the fixed segment near this boundary.

Aim. To evaluate the antitumor efficacy of our developed drug based on cytotoxic T lymphocytes genetically modified with a chimeric antigen receptor (CAR) specific to the CA125 antigen in relation to both CA125-positive and CA125negative cell cultures.Materials and methods. We performed an in vitro study on CA125-positive human ovarian cancer cells (OVCAR-3, OVKATE) and CA125 negative cells (breast cancer MCF 7, embryonic kidney HEK293). Cytotoxic effects on tumor cells were evaluated after 0, 4, 8 and 24 hours using the 3’-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) and Lactate Dehydrogenase (LDH) tests. We also studied the changes in the number of cells “in real time” when exposed to transfected lymphocytes using the RTCA iCELLIgence device (ACEA Biosciences, USA). Lymphokineactivated killer (LAK) cells were used as a specificity control.Results. The study demonstrated that anti-CA125 CAR-T lymphocytes exhibited a pronounced cytotoxic effect on OVCAR-3 and OVKATE cell cultures, exceeding the effect of LAK by 1.3 times. The cell population in the experimental samples decreased by 70 ± 4%, which exceeded the LAK effect by 9 ± 8.2%. With regard to the MCF-7 cell line, the cytotoxic effect of anti-CA125 CAR-T lymphocytes was minimal as evidenced by a 25.8% decrease in the relative number of live cells in comparison to the LAK cytotoxicity of 68%. Real-time monitoring of cell proliferation and viability proved a high specific cytotoxic effect of anti-CA125 CAR-T lymphocytes against tumor cultures expressing CA-125, while inferior to LAK in cultures not expressing CA125 (MCF-7, HEK293).Conclusions. The use of anti-CA125 CAR-T lymphocytes against CA125-positive tumor cell lines OVCAR-3 and OVKATE demonstrated a pronounced specific cytotoxic effect exceeding the cytotoxic effect of LAK, which was not achieved against CA125-negative MCF-7 and HEK293 cells.

The purpose of the current work was to search for sources of winter wheat varieties’ resistance to the most common pathogens of the area under artificial infectious backgrounds and recommend them for inclusion in the breeding process. The study was carried out on the experimental plots of the laboratory for plant immunity and protection of the FSBSI Agricultural Research Center “Donskoy” in 2021–2023. In order to expand the genetic diversity in immunity of newly developed varieties, it is necessary to use new sources of resistance. The objects of study were 78 winter wheat varieties from interstation variety testing, representing various breeding institutions in Russia and some foreign varieties. The study material was presented by the North Caucasian populations of pathogens of such wheat leaf diseases as powdery mildew, brown and yellow rust, and leaf spot (Septoria). Infectious backgrounds were formed according to generally accepted methods, using spore material of pathogens both stored and collected from crops in the previous year (types of rust) and collected from overwintered plants in the spring (powdery mildew, leaf spot). Weather conditions varied across the years of study (mainly in the autumn), but the damage to susceptible test varieties in the experiments was maximum. As a result of the study of the varieties on their resistance to one pathogen, there have been identified 23 varieties resistant to powdery mildew, 56 ones to leaf rust, 47 ones to yellow rust, 8 varieties to leaf spot. There has been given a characteristic of varieties according to various degree of resistance or susceptibility to each pathogen. On the resistance to two pathogens, there have been identified 17 varieties resistant to brown and yellow rust, 2 varieties resistant to brown rust and powdery mildew, 2 varieties resistant to yellow rust and powdery mildew, 1 variety resistant to brown rust and leaf spot. Ten varieties have shown resistance to no one pathogen, but they have had moderate resistance or moderate susceptibility to several other pathogens. 20 varieties were resistant to three diseases in various combinations, and 16 of them were resistant to brown, yellow rust, and powdery mildew. One variety ‘MV Nador’ from Hungary showed resistance to all 4 pathogens. All resistant varieties identified in the study can replenish the supply of winter wheat sources to the complex of leaf diseases for breeding purposes or be used in integrated crop protection against leaf diseases.

The paper analyzes the elemental composition of soils and plants of agrocenosis on the gray forest soil of Vladimir opolye under long-term application of mineral and organic fertilizers. The content of total and mobile forms of Ni, Cu, Zn, Co, Mn, Fe and the content of these elements in aboveground plant organs, as well as changes in the main agrochemical characteristics that can affect the availability of elements to plants were evaluated. It is shown that the application of mineral fertilizers contributes to soil acidification, increase in the content of organic carbon, mobile forms of phosphorus. At the same time, the variants with joint application of mineral and organic fertilizers are subject to less change of these characteristics, which may be due to the increased buffering capacity of the soil with respect to the components coming with mineral salts, due to the applied organic matter. Introduction of Ni, Cu, Zn, Co, Mn, Fe into agrocenosis with fertilizers (organic and mineral) did not affect the gross content of metals in soil. There was a change in the content of mobile forms of metals in the soil due to changes in agrochemical parameters of soils. Changes in the content of trace elements in plant products were recorded. The reduction of Zn, Cu content in plants on the variants with more intensive use of fertilizers (and with higher yield) is explained by "dilution effect". The low content of Co in the soil and its insufficient supply to the plants must be controlled. The joint use of data on changes in the elemental composition of soils and plants allows better differentiation of experimental variants in the space of principal components when analyzed by this method and is promising for monitoring the consequences of agrogenic load of different degrees. The results obtained can be taken into account in the formation of criteria for assessing the mineral nutrition of plants and fertilizer application rates.

Introduction. In the process of soil compaction it is important to have information about the current density of the layer, as it enables to quickly adjust the load on the compacted material. The field methods of compaction quality assessment do not cope with this task, as they make point estimation within the pavement area. Therefore, continuous compaction monitoring systems installed on vibratory road rollers are becoming increasingly common. The systems developed by BOMAG and AMMANN require, among other things, the phase angle between the exciter force and the roller movement to calculate the compaction quality index. The phase angle is determined by the unbalance position sensor, which is very labor-intensive. In addition, continuous compaction monitoring systems include an accelerometer. The purpose of this paper is to develop an indirect method for calculating the phase angle from accelerometer readings.The method of research. In order to achieve the purpose of the work, a roller-soil single-mass model in a typical mode for vibratory rollers (periodic loss of contact) has been studied. As a result of modeling it has been found that the reaction of the compacted material has the main influence on the vertical component of a roller acceleration and practically does not affect the horizontal component. This is confirmed by the experimental data.Results. The phase angle can be determined by mutual correlation of the horizontal and vertical acceleration signals of the roller obtained with the accelerometer.Conclusion. The study proposes a new method of calculating the phase angle between the exciter force and the roller displacement, which eliminates the direct measurement of this angle. The calculation of the angle is based on the readings of a two-axis accelerometer installed on the road roller. The proposed method enables to simplify the system of continuous compaction control and reduce the labor intensity of phase angle measurement.

Introduction. In this paper attention is paid to the study of electrical parameters of fifteen compositions of alternative fuels. The task of developing non-contact methods of fuel composition analysis is relevant. Aim of the Study. The study is aimed at obtaining dielectric constant data of alternative fuels for further search of the relationship with combustion process. Materials and Methods. For the study there was used a capacitor consisting of two 175x102 mm aluminum plates and a Sinometex ZT-Y multimeter. Results. When comparing the dielectric constant values of all presented alternative fuel compositions, there is found the dependence between the minimum and maximum content of added alcohol and vegetable oils in the mixture. This dependence manifests itself in the nature of dielectric constant values correlating with the capacitor electric capacity, if there is the mixture between the plates. It is observed for all three hydrocarbons added to the mixture: ethanol, rapeseed and colza oils. For example, the dielectric permittivity increases throughout the range from 10 to 50% of the added ethanol, rapeseed and colza oils, reaching the values from Ɛ =3.05 to 45.31; from Ɛ = 2.35 to 2.72; from Ɛ = 2.33 up to 2.8, respectively. Discussion and Conclusion. The analysis of the dielectric constant values of various alternative fuel compositions shows that when the content of alcohol and vegetable oils in the mixture increases from 10 to 50%, the dielectric constant increases. And this is true for all three hydrocarbons: ethanol, rapeseed and colza oils.

Different types of models are used to study the stress-strain behavior of asphalt concrete mixture during compaction. For modeling it is necessary to know the values of model parameters in the whole range of changes in the characteristics of the compacted material. The aim of the paper is to develop a methodology for determining model parameters based on the results of laboratory creep-recovery testing of asphalt-concrete mixture. In the paper, a model reflecting elastic, visco-elastic and visco-fluid properties of the compacted material is adopted. A differential equation representing the law of behavior of the asphalt-concrete mixture layer under load is obtained. The stages of creep-recovery testing are analytically described, namely: rapid loading with a constant load and deformation under this load; load removal and recovery. Initial conditions for the mentioned stages are determined. Taking into account the initial conditions, analytical expressions of the laws of deformation of the model under the action of a constant load and in the process of recovery are obtained. The methodology of laboratory experiments on creep-recovery is described, according to the results of which the required values of the model parameters with minimum absolute error are obtained. The developed methodology allows to determine the parameters of the model describing the stress-strain behavior of asphalt-concrete mixture of different density and temperature. Consequently, it is possible to simulate the behavior of the asphalt concrete mixture layer at the preliminary, main and final stages of compaction in order to determine the effective operating modes of compaction equipment.

Background. Rationing of health care—restricting patients’ access to potentially beneficial health care interventions through non-market instruments—is a natural feature of all health care systems as they operate under resource constraints. The purpose of this study is to characterize rationing practices and the attitude of doctors themselves to it, with an emphasis on comparing Russia and the United States and on changes in the perception of rationing during the COVID-19 pandemic. Methods. We conducted a bibliometric analysis of publications in the medical scientific literature since 1989 on the issue of rationing of medical care. To characterize rationing practices in Russia and the United States and the attitudes of doctors towards them, we used data from published studies and data from semi-structured in-depth interviews with 28 Russian doctors. Results. Despite the increasing frequency of publications related to the topic of resource allocation over the past 20 years, studies using the term “rationing” are rare. Both Russia and the USA have practices of explicit and implicit rationing. In Russia they are more diverse and widespread. In both countries, doctors prefer implicit rationing and do not want open discussion of these issues. The practice of rationing is institutionalized. In Russian medical organizations its most common form is a chain of permissions for the use of resources. But most doctors believe they are not rationing care. The pandemic briefly brought the topic of rationing into the public sphere, but then its discussion was limited. The probable reason is that medical practice during the pandemic was carried out within the previous legal framework. Professional organizations have developed several recommendations for rationing, but their usefulness and level of acceptance by professionals and the public is unclear. Conclusions The transition from implicit to explicit rationing is extremely difficult, but is necessary to ensure equitable patient access to scarce medical resources and the effective functioning of health care systems. A major barrier to the explicit and informed use of rationing instrument is the limited public acceptance of it and the reluctance of professional communities to make public decisions that maximize public benefit by prioritizing access to effective interventions.

Статья посвящена дипломатическим контактам Русского государства с Габсбургами в 1519–1531 гг., от смерти императора Максимилиана I до возвращения в Москву последнего посольства, отправленного великим князем Василием III в Прагу. Дом Габсбургов в контактах с Московским государством представляли император Карл V и его брат Фердинанд I – эрцгерцог Австрийский (с 1521/22), король Чехии и Венгрии (с 1526/27), римский король (с 1531). Они были заинтересованы в формировании лиги христианских государей для противостояния османской экспансии, что подразумевало заключение «вечного мира» или по меньшей мере перемирия между Русским государством и Великим княжеством Литовским, соединенным с Польским королевством персональной унией под властью Сигизмунда I Старого. Интересы Василия III и его окружения были противоположными: они заключались в ратификации союзного договора 1514 г., направленного против Ягеллонов и подразумевавшего совместные наступательные действия. С 1526 г., когда в Мохачской битве погиб король Венгрии Лайош (Людовик) II, Фердинанд I вел борьбу за венгерский престол с Яношем Запольяи, которого поддерживала Польша. При этом Карла V занимали в основном дела Западной и Южной Европы, тогда как полномочия в выстраивании международных отношений в Центральной и Восточной Европе он делегировал Фердинанду I. Московско-габсбургский обмен посольствами показал, что московская сторона неохотно вела переговоры с Фердинандом I, несмотря на его заинтересованность в них, стремилась контактировать с императором и не раскрывала антиягеллонского содержания договора 1514 г., предлагая «возобновление дружбы и любви». Принципиальное расхождение целей сторон и особенности их коммуникации привело к тому, что союзный договор так и не был ратифицирован. Центральное место в статье занимает анализ сведений о московском посольстве 1528 г. – четвертой из пяти миссий, отправленных Василием III к Габсбургам за указанный период. В приложении публикуется с переводом на русский язык новый источник об этом посольстве – письмо Фердинанда I, короля Чехии, Маргарите Австрийской, наместнице Фландрии, от 28 июля 1528 г., о проезде московского посланника к императору Карлу V в Испанию.

Perfluoroorganic compounds are surgically invasive medical devices, which are represent liquid fluorine-containing substances, chemically and biologically inert and thermodynamically stable due to the strength of chemical bonds between carbon and fluorine atoms. Due to their density, these compounds are able to exert pressure on the detached retina and expel the subretinal fluid. Currently, the use of perfluoroorganic compounds is limited to intraoperative use due to multiplesevere complications of prolonged tamponade. In the analyzed studies, the use of perfluoroorganic compounds as a tamponade was divided into short-term and medium-term tamponade of the vitreal cavity. The authors preferred such tactic for restoring the anatomical fit and a higher rate of aging of retinal laser coagulates, despite proven postoperative complications. Based on the analysis of the results of the presented studies, it can be concluded that it is possible to safely use perfluoroorganic compounds for short-term tamponade of the vitreal cavity. However, among the analyzed domestic and foreign studies, no large-scale statistically significant studies were found to justify the choice of tamponade for retinal breaks different localization, terms of retinal detachment and stage of proliferative vitreoretinopathy. All of that determines the relevance of a more detailed study of the use of perfluoroorganic compounds for short-term tamponade of the vitreal cavity.

Cardiovascular diseases and obesity are related medical and social problems. However, some obese people remain free of cardiovascular disease for long periods of time, and the concept of obesity phenotypes that differ in cardiovascular risk has been actively studied. Currently, there are no generally accepted diagnostic criteria for them, and the mechanisms underlying their formation remain unclear. The purpose of this article is to discuss the literature data on obesity phenotypes, their relationship with cardiovascular diseases and mortality, as well as the place of obesity in the domestic algorithm for diagnosing stable coronary heart disease.

Rhegmatogenous retinal detachment (RRD) is one of the leading causes of primary vision disability, while the majority of RRD patients with RRD are people of active working age. Over the past 50 years, retinal detachment surgery has been progressing rapidly, the rate of success increasing up to 90% or higher. However, the reduction of reoperation risks of reoperations, improvement of functional outcomes and increase of postoperative visual acuity remain topical issues. The main reason for repeated surgical interventions is the proliferative vitreoretinopathy progression, which can lead to epiretinal fibrosis, macular oedema, or retinal detachment recurrence. The review is focused on current literature studies that report the results of internal limiting membrane peeling in cases of RRD surgeries and other optional techniques aimed at reducing the risk of the above mentioned postoperative complications.

Abstract The ongoing progress of superconducting logic systems with Josephson junctions as base elements requires the development of compatible cryogenic memory. Long enough junctions subject to magnetic field host quantum phase 2π-singularities—Josephson vortices. Here, we report the realization of the superconducting memory cell whose state is encoded by the number of present Josephson vortices. By integrating the junction into a coplanar resonator and by applying a microwave excitation well below the critical current, we are able to control the state of the system in an energy-efficient and non-destructive manner. The memory effect arises due to the presence of the natural edge barrier for Josephson vortices. The performance of the device is evaluated, and the routes for creating scalable cryogenic memories directly compatible with superconducting microwave technologies are discussed.

Retinal detachment with a macular hole is a severe pathology leading to vision loss and disability of the patient. It is most frequently observed in myopes and causes severe damage of functional parameters of the retina. The pathogenesis of the disease is associated with tangential tractions of the inner limiting membrane and the posterior layers of the vitreous that affect the retina of the myopic eye. Modern ophthalmology uses a variety of approaches to the surgical treatment of the pathology. The final functional result primarily depends on how successful the macular hole closure and retinal reattachment are. To achieve this success, various techniques of subretinal fluid drainage can be used. The present literature review was conducted using the Pubmed search engine. We analyzed the articles published from 2000 to 2021. The analysis of research results showed the advantage of the peripheral method of drainage using a perfluoroorganic compound. This technique is relevant both in cases of the peripheral retinal tear and in subretinal fluid aspiration through the retinotomy. The peripheral method of drainage using a perfluoroorganic compound ensures a better functional outcome, which, in case of retinal detachment with a macular hole, mainly depends on the safety of the neuroreceptors of the central zone and the closure of the macular hole.

The current paper has presented the materials for studying collection samples of winter common wheat for resistance to leaf and smut diseases for use in breeding programs for immunity. The current study was carried out based on the FSBSI Agricultural Research Center “Donskoy” in 2021–2023. The objects of the study were 98 samples from the collection CUMMIT (Turkey). The objects of study were the North Caucasian populations of pathogens of leaf diseases, such as powdery mildew, brown and yellow rust, septoria and local populations of pathogens of loose and kernel smut. The study was carried out on field infectious backgrounds of diseases with artificial infection of plants in accordance with the methodological instructions for each of them. The purpose of this work was to identify winter wheat samples resistant to both individual pathogens and their complex. Susceptible test varieties of winter wheat had maximum damage scores for each disease studied. During the study there have been identified 19 samples resistant to powdery mildew, 67 samples resistant to leaf rust, 63 samples resistant to yellow rust, 2 samples resistant to septoria, 95 samples resistant to loose smut and 25 samples resistant to kernel smut. There have been identified samples 9855, 9859, 9883, 9884, 9894 that showed resistance or weak susceptibility to brown and yellow rust, powdery mildew, septoria, etc. 15 samples 9802, 9812, 9898, 9899, 9903 were not affected by loose and kernel smut. A number of samples that have demonstrated complex resistance to smut diseases over three years were 9855, 9859, 9884, 9894, 9883, 9902, etc. The sample 9859 showed high resistance to five diseases. The best samples in terms of complex resistance could be recommended for breeding programs for immunity.

The rapid spread of obesity and associated cardiovascular disease is of serious concern in the scientific and medical field. Despite diverse approaches to solving these problems, there is still no visible success in the fight against obesity at the population level, and cardiovascular pathology still remains one of the main causes of death and disability in the world. This leads to attempts aimed at finding new therapeutic options. Targeted pharmacological therapy for adipose tissue dysfunction represents one of the potential solutions. In the present article, we review the effects of adipocytokines such as adiponectin and leptin, as one of the most well-studied markers of disruption of the normal functioning of adipose tissue, as well as some modern approaches to pharmacological correction of their effects on the cardiovascular system. The analysis of the data shows that hypoadiponectinemia and hyperleptinemia in combination with leptin resistance are associated with cardiovascular disease and poor prognosis, and correction of pathologically altered levels of the above-mentioned adipocytokines to achieve their optimal ratio may represent a relevant therapeutic goal.

A general approach is presented for synthesizing alkyne-modified nucleoside triphosphates via the Sonogashira cross-coupling reaction of unprotected halogenated 2ʹ-deoxynucleoside, followed by monophosphorylation and the reaction of the corresponding phosphoromorpholidate with tributylammonium pyrophosphate. A highly efficient approach for the milligram-scale synthesis of base-modified nucleoside triphosphates with an amino acid-like side chain was developed. The present chemical method outweighs the other reported methods of a base-modified nucleoside triphosphates synthesis in terms of it being a protection-free strategy, the shortening of reaction steps, and increased yields (about 70%). The resulting 8-alkynylated dATP was tested as a substrate for DNA polymerases in a primer extension reaction.