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One of the modern approaches for the effective development of small deposits is the construction and operation of wells with a complex architecture: horizontal wells (HW), sidetracks (BS, BGS), multilateral wells (MLW). Sidetracking makes it possible to reanimate an old well that is in an emergency state or inactivity for technological reasons, by opening layers that have not been previously developed, bypassing contamination zones, or watering the formation. This study examines the possibility of using horizontal sidetracks in the operating wells of the field of the Zhetybai group. To select the optimal length of the horizontal sidetrack of the wells, graphs of the dependences of the change in flow rate versus length of the horizontal well were built, taking into account the pressure losses due to friction. It can be seen from the dependence of NPV versus length of the horizontal wellbore that the maximum NPV is achieved with a horizontal wellbore length of 100 m. A further increase in the length of the horizontal wellbore leads to a decrease in NPV. This is due, firstly, to a decrease in oil prices, and secondly, interference of wells, a small number of residual reserves, and a small oil-bearing area. As a result of a comparison of technical and economic criteria, the optimal length of a horizontal wellbore is from 100-300 meters. Comparison of the flow rates of vertical wells and wells with horizontal sidetracks showed a clear advantage over the latter in all respects.

Coronaviruses (CoVs) pose a huge threat to public health as emerging viruses. Bat-borne CoVs are especially unpredictable in their evolution due to some unique features of bat physiology boosting the rate of mutations in CoVs, which is already high by itself compared to other viruses. Among bats, a meta-analysis of overall CoVs epizootiology identified a nucleic acid observed prevalence of 9.8% (95% CI 8.7–10.9%). The main objectives of our study were to conduct a qPCR screening of CoVs’ prevalence in the insectivorous bat population of Fore-Caucasus and perform their characterization based on the metagenomic NGS of samples with detected CoV RNA. According to the qPCR screening, CoV RNA was detected in 5 samples, resulting in a 3.33% (95% CI 1.1–7.6%) prevalence of CoVs in bats from these studied locations. BetaCoVs reads were identified in raw metagenomic NGS data, however, detailed characterization was not possible due to relatively low RNA concentration in samples. Our results correspond to other studies, although a lower prevalence in qPCR studies was observed compared to other regions and countries. Further studies should require deeper metagenomic NGS investigation, as a supplementary method, which will allow detailed CoV characterization.

Формирование цены в процессе международной торговли всегда привлекало внимание экономистов, поскольку процесс установления пропорций обмена и его влияние на уровень жизни поддаются непосредственной эмпирической проверке и существенно воздействуют на экономический рост стран, вовлеченных в торговые отношения. Неудивительно, что исторически первыми теориями международной торговли стали такие теории, которые предполагали неэквивалентность обмениваемых друг на друга товаров. Прежде всего речь идет о меркантилистской школе, которая рассматривала международную торговлю, как один из основных источников обогащения одних и обнищания других народов. Несмотря на то, что представители школы имели разные воззрения на природу стоимости товаров, они строго придерживались идеи неэквивалентного обмена торгуемых благ.

The work resulted in theoretical developments for the study of the spatial aspects of the latest practices in live arts, as well as the identification of social and cultural contexts that are key to the history of art in situ in Russia. The negative aesthetics of theatrical events mastering non-theatrical spaces: streets, foyers, roofs, squares, natural landscapes open up the possibility of analyzing the theatrical process and its auto-reflective function. Theatrical and performative events turn out to be closely integrated into such social processes as cultural democratization (inclusion of more and more new groups in the processes of cultural interactions), commemoration (the creation of new rituals and narratives for memory and preservation of cultural heritage), as well as in the processes of creating and drawing attention to the public spaces of a modern city. We believe that a necessary step for the development of the theory of contemporary art is the inclusion of a cross-disciplinary understanding of the object of study, in which live performing arts, installation arts, visual arts, video and audio experiments in exhibition projects would be considered together and thus the ideas and concepts of post-structuralist cultural criticism could be applicable to the contemporary art process.&nbsp

Vein-specific inflammation leads to vascular smooth muscle cells proliferation and extracellular matrix degradation of vein wall. This process is known as remodeling and is promoted by "trapped" leukocytes. Monocyte chemoattractant protein 1 (MCP-1) is a chemokine responsible for trafficking of leukocytes from blood to vein wall. The aim of this study was to measure the MCP-1 concentration in varicose veins blood before and after venoactive drug therapy and to compare it with a concentration of blood from varicose veins of subjects who did not receive drug treatment.Non-randomized comparative study was conducted on 30 patients with primary varicose veins. 20 patients of the study group received diosmin 900 mg/hesperidin 100 mg once daily. 10 controls received no treatment. MCP-1 level was measured (pg/ml) in the blood from varicose veins twice, at the day of inclusion and after 60 days. Legs discomfort related to chronic venous disease (CVD) symptoms was measured with 10-cm visual analogue scale (VAS) at inclusion and at completion of the study.Median (interquartile range, IQR) MCP-1 concentrations in treatment and control groups at inclusion were 171.9 (124.4-216.0) and 157.0 (120.1-163.1), resp., p=0.285. After 60 days of treatment MCP-1 level decreased, but non-significantly to 152.3 (124.1-178.3). In patients who did not receive treatment chemokine level slightly increased to 163.0 (134.0-172.9). Median changes over time were -6.6 (-30.9 - 7.4) and 10.6 (-3.7 - 19.2) in the study and control groups, resp. (p=0.048). After 60 days in 12 of 19 and 2 of 9 patients of treatments and control groups MCP-1 decreased (p=0.103). Odds ratio for MCP-1 decreasing was 9.5 (95% CI 1.1-81.5, p=0.043) for those who received venoactive drug. Mean (+ standard deviation, SD) legs discomfort significantly dropped in the study group from 5.7 (+2.5) to 1.9(+2.2) (p=0.0003), while in controls no changes were registered: 3.4 (+1.3) and 3.5 (+ 1.4), resp., p=0.28). Mean difference of VAS at baseline and at follow-up was -3.5 (+2.6) and 0.9 (+2.1), resp. (p0.0001).Plasma concentration of MCP-1 in varicose veins blood demonstrates a tendency to decrease under two months treatment with a venoactive drug. Future studies are needed to reveal a possible role of MCP-1 as a target considering its role in varicose veins pathogenesis.

The introduction of 5G technology along with the exponential growth in connected devices is expected to cause a challenge for the efficient and reliable network resource allocation. Network providers are now required to dynamically create and deploy multiple services which function under various requirements in different vertical sectors while operating on top of the same physical infrastructure. The recent progress in artificial intelligence and machine learning is theorized to be a potential answer to the arising resource allocation challenges. It is therefore expected that future generation mobile networks will heavily depend on its artificial intelligence components which may result in those components becoming a high-value attack target. In particular, a smart adversary may exploit vulnerabilities of the state-of-the-art machine learning models deployed in a 5G system to initiate an attack. This study focuses on the analysis of adversarial example generation attacks against machine learning based frameworks that may be present in the next generation networks. First, various AI/ML algorithms and the data used for their training and evaluation in mobile networks is discussed. Next, multiple AI/ML applications found in recent scientific papers devoted to 5G are overviewed. After that, existing adversarial example generation based attack algorithms are reviewed and frameworks which employ these algorithms for fuzzing stat-of-art AI/ML models are summarised. Finally, adversarial example generation attacks against several of the AI/ML frameworks described are presented.

Introduction. The efficiency of the metalworking processes highly depends on the performance of the implemented cutting tools that can be increased by studying its stress-strain state and temperature fields. Existing stress analysis methods either have a low accuracy or are inapplicable for research during the operation of the tools made of materials with high mechanical properties. In addition, the study of temperature fields using known methods is difficult due to the small size of the cutting zone, high temperatures, and a heavy temperature gradient appearing during metal cutting. The purpose of this study is to develop new experimental methods for measuring the stress-strain and temperature fields in the cutting tool during its operation using laser interferometry. The methods include: obtaining interference fringe patterns using an interferometer with the original design, obtaining the tool deformation field during the cutting process by recording the changes in interference fringe patterns using a high-speed camera, processing fringe patterns with the separation of deformations caused by heating and cutting forces, and calculating temperature fields and stress distributions using mechanical properties and the coefficient of thermal expansion of the tool material. The advantages of the developed methods include: applicability under real operating conditions of the cutting tool, ability to study the non-stationary stress-strain state and temperatures during an operation, and achievement of a high spatial resolution and a small field of view for the investigated surface. Results and Discussion. The experimental study confirmed the efficiency of the methods. The results of the study included the fields of stresses and temperatures obtained during the orthogonal cutting of heat-resistant steel with a tool made of cemented tungsten carbide WC-8Co. The developed methods can be used to study the cutting tool efficiency at close to real conditions and in obtaining boundary conditions for the study stress-strain state of a workpiece material near the cutting zone.

Efficient and ambient synthesis of aromatic polyimides (PIs) from readily available starting materials remains a very challenging task in polymer chemistry. Herein, we report for the first time a r...

Using sequential electron-beam evaporation of high-temperature dielectric (alumina ceramic) and magnetic (iron) targets in various gas atmospheres (helium, air, and oxygen) in medium vacuum (5–8 Pa), magneto-dielectric coatings with thickness of around 2 μm were deposited from a multicomponent beam plasma at a deposition rate of 0.2–0.3 μm/min. The coating magnetic properties were explored by the ferromagnetic resonance technique, revealing that their effective magnetization depends on the type of operating gas and varied from 4.2 to 6.8 kGs (for deposition in helium) to 0.3 kGs (in oxygen), which is characteristic of oxide ferromagnetic materials and is considerably lower than the corresponding value (∼22 kGs) for thin iron films formed by vacuum arc deposition in high vacuum. X-ray structural analysis of coatings deposited in medium vacuum in helium showed that the magnetic layer has a magnetite (Fe3O4) structure. The alumina ceramic layer provides the dielectric properties of the magneto-dielectric coating; a relative dielectric constant of 6.0 and a conductivity of 8.4 mS/m were achieved.

A forecast of coke quality takes a special place in the coke production, since it enables to increase efficiency of management of batching process of various by composition and properties coals and production of coke of stably high and required quality with minimal costs. Description of a methodological approach to processing of passive industrial experiment data of blends coking at Coke production department of JSC EVRAZ NTMK presented by application selective (general) matrix. The matrix accounts various multilevel values of influence factor CSR and CRI of coke - a complex index of coking ability of blends K.п.к.Vo. It was shown that the proposed approach provides wide variations of response function (CSR/CRI) at symmetrical enough matrix, excluding predominance of any particular area of values of indices K.п.к.Vo and CSR/CRI. By applying the passive industrial experiment, based on processing of actual report data of industrial blends coking at the coke batteries No. 5-6 (wet quenching) and No. 9-10 (dry quenching) by selective matrix, mathematical models of forecast of quality of industrial coke by wet and dry quenching (CSR/CRI) were elaborated depending on coal charges properties (K.п.к.Vo) at the existing modes of their preparation and coking at the coke batteries No. 5-6 and 9-10. Verification of accuracy of the mathematical models of coke quality forecast at wet and dry quenching (CSR/CRI) processing a large actual material of industrial coking (62 coking operations in the coke batteries No. 5-6 and 58 coking operations in the coke batteries No. 9-10 showed accuracy good enough for practical application of forecasting indices CSR and CRI of industrial coke of wet and dry quenching.

VT transition from the high-spin CoII to low-spin CoIII state was observed for complex (N-cyclo-hexyl-2-iminopyridine)(3,6-di-tert-butyl-o-benzosemiquinonato)(3,6-di-tert-butyl-catecholato)cobalt i...

The paper examines the features of the linguistic discourse in French-language texts of modern scientific papers. The study proves that within the framework of studying linguistic texts, it is necessary to distinguish between the concepts of object-language, scientific theory, metalanguage, scientific discourse and metadiscourse. The analysis of 50 scientific articles based on the results of the World Congress in French Linguistics 2020, revealed metalinguistic, discursive and metadiscursive units that correspond to the levels and components of linguistic theory.