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A shortage of class 2 and class 3 tractors was observed in peasant farms. As a solution to this problem, it was proposed to develop a technological module that would increase the versatility of class 1.4 tractors by transferring them to a higher traction class. (Research purpose) The authors aimed to substantiate the nominal operating power of the engine for a tractor with a technological module. (Materials and methods) To calculate the required power, the authors proposed a method that takes into account the design features of the modular construction of a machine-tractor unit. (Results and discussion) The authors showed that for a modular power unit with a 6K6 wheel arrangement, it is necessary to consider a number of additional factors having an impact on the accuracy of the calculation: firstly, the tractor’s traction and coupling properties depend on the number of driving axles; secondly, the wheel slippage along individual axes is not the same and occurs due to a constructively conditioned kinematic discrepancy in their drive; thirdly, the three-axle transmission efficiency can be determined only as a total indicator of three transmission branches, that is, to drive the tractor front and rear wheels and, separately, to drive the wheels of the technological module. The authors compared the required engine power when using a tractor with ballast and that with a technological module. (Conclusions) It was determined that in order to achieve the maximum traction force of adhesion on the hook when moving to the next higher traction class, it is necessary that the tractor, that the technological module is joint to, has the energy saturation of 2.00-2.41 kilowatts per kilonewton, which corresponds to traction and energy concept tractors whose engine power cannot be realized through traction. It was found that the power saturation of the tractor with the technological module will be equal to 1.59-1.65 kilowatts per kilonewton, which corresponds to the tractor of the traction concept and allows realizing the built-in engine power through traction.

A graph G arrows a graph H if in every 2-edge-colouring of G there exists a monochromatic copy of H. Schelp had the idea that if the complete graph $K_n$ arrows a small graph H, then every ‘dense’ subgraph of $K_n$ also arrows H, and he outlined some problems in this direction. Our main result is in this spirit. We prove that for every sufficiently large n, if $n = 3t+r$ where $r \in \{0,1,2\}$ and G is an n-vertex graph with $\delta(G) \ge (3n-1)/4$ , then for every 2-edge-colouring of G, either there are cycles of every length $\{3, 4, 5, \dots, 2t+r\}$ of the same colour, or there are cycles of every even length $\{4, 6, 8, \dots, 2t+2\}$ of the samecolour.Our result is tight in the sense that no longer cycles (of length $>2t+r$ ) can be guaranteed and the minimum degree condition cannot be reduced. It also implies the conjecture of Schelp that for every sufficiently large n, every $(3t-1)$ -vertex graph G with minimum degree larger than $3|V(G)|/4$ arrows the path $P_{2n}$ with 2n vertices. Moreover, it implies for sufficiently large n the conjecture by Benevides, Łuczak, Scott, Skokan and White that for $n=3t+r$ where $r \in \{0,1,2\}$ and every n-vertex graph G with $\delta(G) \ge 3n/4$ , in each 2-edge-colouring of G there exists a monochromatic cycle of length at least $2t+r$ .

Purpose. Study of the reasons for culling cows from the herd depending on belonging to Holstein lines. Methods. Materials of breeding and zootechnical accounting of the Selex database and breeding cards of cows were used for research. Results. The farm breeds animals that belong to the following genealogical lines: Vis Back Idial 1013485, Reflection Sovering 198998, Montwick Chieftain 95679, Pabst Governor 882933 and Annas Adema 30587. The cull was 92 heads or 14.3 %, including lines: 21, 33, 25, 6, 7 heads or 10,0; 18.9; 12.3; 15.8; 41.2 % accordingly. Analysis of the reasons for culling by groups of cows of different lines showed that among the culled cows of the Vis Back Idial line 1013485 there were more than in other groups with pathology of the musculoskeletal system – 37.5 %; the Reflection Sovering line 198998 – accidents and injuries – 34.6 %; in the group of cows of the Montwick Chieftain line 95679, a significant number of cases of breast pathology – 27.2 % and in general, the main reasons for culling on the farm are injuries and surgical diseases – 33.7 %; pathology of the breast – 21.7 % and pathology of the reproductive system and barrenness – on 16.3 %. Despite the fact that the farm has created quite good conditions for ensuring the normal life of cows, including a balanced feeding diet, which is indicated by a low percentage of culls associated with metabolic pathology, cases of poisoning were detected – 8.7 %. Existing violations of the content are confirmed by a significant number of injuries, accidents, and limb diseases. The scientific novelty of the work lies in the fact that the influence of origin (belonging to the line) on the level of culling of breeding stock for one reason or another has been proved, which allows through breeding work to have a positive impact on increasing the duration of productive use.

The aim of this article is to assess the structure of biodiversity of field protective forest shelter belts to determine the directions of increasing their reclamation and conservation potential in the organic agricultural landscape. Methods of comparative ecology (synecological approach, assessment of α-diversity), forestry, geobotany, ornithology and statistical analysis are used. Changes in species diversity of plants and birds in forest shelter belts around organic fields are characterized. It is established that plantations with developed undergrowth and under-storey are transformed due to the loss of up to 43.5% of trees, liquefaction of the edificatory tier. Transformer species with a wide phytocenotic range predominate in the tree stands. The grass tier is dominated by ruderants (36.5%) and adventive species (24.5%). The share (60%) of species with a mixed life strategy indicates changes in moisture conditions and soil trophism. A 2.4% of shade-loving plants and the presence of 14.7% nitrophils indicate an imbalance in the structure of forest shelter belts. Depletion of species composition, ecological and trophic structure of bird groups testify to the decrease in the capacity of forest shelter belts and their statio diversity, reduction of protective, environment-creating functions and other ecosystem services. In the three-tiered dense forest shelter belts with developed undergrowth and understorey, 10–27 species of birds nest. In general, avifauna is represented by 2 ecological groups (93.1% dendrophiles, 6.9% sclerophiles), divided into 5 types of nesting strategy (with a predominance of hollow-nests 37.0–53.3%), and 5 types of feeding (with a predominance of entomophagous 70.4–90.0%). Twenty-nine species have been identified on nesting, 27 of which are subject to protection at the level of international agreements. There are no adventive species, the index of synanthropization of avifauna is high – 0.85–1.0. For organic technologies to increase the potential of biological protection of fields from entomological pests by attracting insectivorous birds is relevant.

Rhodococcus bacteria are a promising platform for biodegradation, biocatalysis, and biosynthesis, but the use of rhodococci is hampered by the insufficient number of both platform strains for expression and promoters that are functional and thoroughly studied in these strains. To expand the list of such strains and promoters, we studied the expression capability of the Rhodococcus rhodochrous M33 strain, and the functioning of a set of recombinant promoters in it. We showed that the strain supports superexpression of the target enzyme (nitrile hydratase) using alternative inexpensive feedings-acetate and urea-without growth factor supplementation, thus being a suitable expression platform. The promoter set included Ptuf (elongation factor Tu) and Psod (superoxide dismutase) from Corynebacterium glutamicum ATCC13032, Pcpi (isocitrate lyase) from Rhodococcus erythropolis PR4, and Pnh (nitrile hydratase) from R. rhodochrous M8. Activity levels, regulation possibilities, and growth-phase-dependent activity profiles of these promoters were studied in derivatives of the M33 strain. The activities of the promoters were significantly different (Pcpi < Psod ≪ Ptuf < Pnh), covering 103-fold range, and the most active Pnh and Ptuf produced up to a 30-50% portion of target protein in soluble intracellular proteins. On the basis of the mRNA quantification and amount of target protein, the production level of Pnh was positioned close to the theoretical upper limit of expression in a bacterial cell. A selection method for the laboratory evolution of such active promoters directly in Rhodococcus was also proposed. Concerning regulation, Ptuf could not be regulated (2-fold change), while others were tunable (6-fold for Psod, 79-fold for Pnh, and 44-fold for Pcpi). The promoters possessed four different activity profiles, including three with peak of activity at different growth phases and one with constant activity throughout the growth phases. Ptuf and Pcpi did not change their activity profile under different growth conditions, whereas the Psod and Pnh profiles changed depending on the growth media. The results allow flexible construction of Rhodococcus strains using the studied promoters, and demonstrate a valuable approach for complex characterization of promoters intended for biotechnological strain construction.

Electro-optic properties of Ba0.8Sr0.2TiO3 (BST) film with a thickness of 1 μm deposited on the MgO (001) substrate by the rf sputtering have been studied. Structural features of the film were identified by X-ray diffraction method. It was shown, that the BST film exhibited a predominantly linear EO behavior under the applied static electric field, that have been explained according to the strong compressive stresses in the film. The polarization distribution across the gap between the electrodes when electric field is applied was also investigated experimentally and calculated. The linear EO coefficient of Ba0.8Sr0.2TiO3 film with a thickness of 1 μm film was found to be rc = 99.4 p.m./V, that is promising for various EO applications, for example, high performance EO modulator.

The purpose of the research is to study the tools necessary to improve the quality of natural and organic agricultural products, as well as to increase the volume of their receipts and sales in the Russian agro-industrial complex and retail chains. In the context of the current crisis and sanctions from the United States and a number of countries of the European Union the problem of food security in our country is of particular importance. One of the main tasks of agriculture is not only solving the problem of import substitution by increasing the production of essential products, but also improving their quality. The analysis of the materials made it possible to assess the current state of the food market in Russia. The state mechanism for regulating prices in the food market was analyzed. To solve this problem, it is proposed to use the positive experience of China, Western European countries and our country in different historical periods. Methods. The basic research methods of the posed problem applied in the work are comparison, deduction, modeling, historical and logical methods. The result of the research carried out in this article is an attempt to establish the reasons for the insufficiently developed and implemented subsidized mechanism of state financing in the agricultural sector. In the course of the research, the prerequisites and reasons for the current circumstances were considered and indicated. The scientific novelty is based on the authors’ conclusion of a scientifically grounded concept about the need to bring the branches of agriculture within the framework of a mixed market economy into the non-market sector. This, in turn, can provide an urgent need for self-sufficiency.

Objective. The article deals with the problem of ensuring the rigidity of a frame wooden multi-story building and ways to achieve the necessary spatial rigidity, taking into account the requirements of preserving the internal volume and free space. The case of excess spatial rigidity and measures to optimize it are provided to increase the economic efficiency of the project.Methods. A simpler and less time-consuming method is the initial estimation of the cross-sectional area of the rigid elements that take the wind load. The authors propose a method for the preliminary calculation of building stiffness with subsequent adjustment in the calculation scheme.Results. The design scheme of the building frame is made in the Scad Office software package to take into account the influence of the own structure weight, the redistribution of forces and movements due to the spatial work of the frame, with subsequent adjustment of the cross-sections of rigid elements.Conclusion. The most rational and least time-consuming method for numerical calculation of stiffness is the initial estimation of the cross-sectional area of the system of rigid elements. With its help, it is possible to avoid an excess of spatial rigidity of the building and reduce the time and labor costs for selecting the location of rigid elements.

The ability to control the bandgap in two-dimensional graphene-like semiconductors is an essential task for the development of optoelectronic and nanoelectronic devices. Complex compositions alloys of transition metal dichalcogenides, such as MoxW1-x Se2yS2(1-y), are the most optimal candidates for this purpose. Here we present spectrally selective photodetectors based on such quaternary transition metal dichalcogenides monolayers. It is shown that the spectral selectivity of optical detectors can be changed in a wide range if the composition of these quaternary monolayer transition metal dichalcogenides varies. This effect is directly related to the significant influence of the composition of such two-dimensional semiconductors on their bandgap. A theoretical model for estimation of quaternary transition metal dichalcogenides optical coefficients and optical detectors on their basis is proposed. The optical absorption simulation in created detectors was made, the results of which qualitatively coincided with the detectors performance. Thus, the obtained results can contribute to the development of valleytronics for two-dimensional semiconductor structures.

The paper presents the results of studies on the development of metrological support for DNA sequencing. The sequencing of a standard sample of the human mitochondrial DNA was carried out according to the Sanger method on domestic capillary electrophoresis genetic analyzers Nanophore 05. The results of the work were used to validate standard reference material for human mitochondrial DNA sequence and to confirm the DNA sequencer as a measurement instrument.

The article considers the rationale for the optimal mineral composition of friction geomodifiers for improving the tribological properties of friction surfaces. The practice of maintenance and repair of automotive equipment can be significantly supplemented by non-traditional tribotechnics for the non-selective restoration of worn-out friction interfaces and prevention of new equipment. The use of friction geomodifiers as an additive to lubricants dramatically changes the friction conditions. (Research purpose) The research purpose is in developing a methodology for selecting the optimal mineral composition for friction geomodifiers to the technologies of maintenance and repair of machinery and equipment. (Materials and methods) The article describes a study of 27 minerals for tribo-compositions using the ii5018 friction machine using the traditional method. (Results and discussion) A statistical analysis of the results of tribo-tests of different mineral compositions was performed to assess the effect of the petrocomposition on the effectiveness of friction geomodifiers...

The development of standard requirements in the technique and methods of their determination is an urgent problem whose solution will give the opportunity to policy authorities and producers not only to solve current problems related to the vehicle fleet, but also to determine future needs for technology for Russia as a whole, regions, and farms of all types. (Research purpose) The research purpose is in developing a methodology for calculating the normative need for equipment for crop production using coefficients for converting physical units of equipment into reference units, which allows us to assess the potential efficiency of the fleet, taking into account the main indicators of the technical level for the entire type-size range of machines based on updated data on technologies and characteristics of machines. (Materials and methods) Authors analyzed the state of the machine and tractor fleet and identified negative problems with the equipment of different types of farms. The article presents summarized extensive statistical data on the dynamics of changes in production indicators of major agricultural crops. The conditional (reference) coefficients were studied and clarified. (Results and discussion) The article describes the main provisions of the research carried out in the Federal Scientific Agroengineering Center VIM on determining the normative need of agriculture in technology using conditional (reference) coefficients, which can be used by both farm specialists and relevant ministries. The use of conditional (reference) coefficients allows us to assess the existing level of provision of regions and the country as a whole with the necessary machines and determine the standard demand and the number of equipment of various sizes that should be purchased. (Conclusions) The forecast data provide a benchmark showing the direction of development of mechanical engineering and mechanization of agricultural production. As the structure of acreage changes, as well as their increase or decrease, the need for equipment should be adjusted.

The Erd\H{o}s-Simonovits stability theorem states that for all \epsilon >0 there exists \alpha >0 such that if G is a K_{r+1}-free graph on n vertices with e(G) > ex(n,K_{r+1}) - \alpha n^2, then one can remove \epsilon n^2 edges from G to obtain an r-partite graph. F\"uredi gave a short proof that one can choose \alpha=\epsilon. We give a bound for the relationship of \alpha and \varepsilon which is asymptotically sharp as \epsilon \to 0., Comment: 12 pages, 1 figure

A stabler ignition and combustion of the premixed air/fuel mixture remains a topic of great interest due to the high demand for effective and efficient propulsion systems in aerospace applications. Extensive experimental studies and numerical simulations have been carried out to understand and develop ignition systems using cold and non-thermal plasma in microwave streamer discharges. Use of sub-critical streamer discharge allows to ignite air/fuel mixture by an external electric field whose intensity is significantly lower than the intensity required to induce air breakdown. Ignition and combustion of air/propane mixture by microwave sub-critical streamer discharge in low- and high-speed flows is studied experimentally. Qualitative (flame structure) and quantitative (size of combustion region, temperature distributions) characteristics of the flame zone are provided for different flow speeds and equivalence fuel/air ratios, and conditions of discharge initiation with metallic microwave vibrator are studied. The streamer discharge makes it possible to create multiple ignition points providing almost instantaneous ignition of entire volume of the mixture. The results show that the sub-critical streamer discharge can potentially be used in various applications providing more rapid and efficient combustion.

The effect of dimethyl sulfoxide on the copolymerization kinetics and reactivity parameters of N-vinyl succinimide has been studied. Based on a comparison of the results obtained for the copolymerization kinetics of N-vinyl succinimide with vinyl acetate and styrene in dimethyl sulfoxide, general tendencies in changing N-vinyl succinimide reactivity are revealed. It is proven that the complexation between monomeric molecules and dimethyl sulfoxide as an electron-donor solvent leads to a decrease in the relative reactivity of N-vinyl succinimide. Changes in the Alfrey–Price Q–e parameters for N-vinyl succinimide in the course of complexation have been analyzed. The reasons for the change in the reactivity of the monomer are revealed.

A laboratory magnetic resonance imager for small objects that operates in a field of 7 mT is described. The hardware of the tomograph makes it possible to perform experiments on different nuclei and to use double irradiation methods. The high degree of absolute uniformity of the constant magnetic field allows the use of relatively weak gradients to obtain images. The tomograph can be used to develop new methods of magnetic resonance imaging for the purpose of training physicists and engineers in the methods of obtaining magnetic resonance images and for the study of small objects.

The state of the Russian tractor industry is characterized by deep restructuring processes. This problem is particularly acute in the development of modern mobile low-power tools for mechanization of work in peasant farms. (Research purpose) The research purpose is in substantiating the initial requirements for a new-generation agricultural universal block-modular power tool that meets world standards in terms of technical level, economic and ergonomic requirements, versatility and competitiveness. (Materials and methods) According to the monitoring, the production of agricultural tractors in Russia for the period 1990-2019 decreased by 23.4 times. A new technological direction for the development of mobile power tools was to increase energy efficiency in the full life cycle by reducing the structural weight, fuel consumption and increasing productivity. The article offers innovative design and technological solutions. (Results and discussion) The article describes the initial requirements for agricultural mobile power tools based on statistical analysis of data on the need for agricultural mobile power tools, analysis of existing and future technologies and agricultural machines, as well as current standards for mobile power tools. (Conclusion) The article presents developed initial requirements for an agricultural universal block-modular energy tool that will ensure environmental safety, competitiveness, reduce the total specific energy intensity of performing a unit of useful work by 1.4-1.6 times, and will also significantly increase the level of marketability and profitability of agricultural production in peasant farms.

Currently, not a single serially produced vehicle used in agriculture meets the requirements of the state standard for the maximum permissible impact of propellers on the soil. This leads to significant losses and shortage of agricultural products. As a promising direction for increasing the efficiency of the transport infrastructure of agricultural production, it is proposed to develop an environmentally friendly transport and technological chassis for agricultural purposes.

The dependence of the noise density in a signal of a fiber-optic towed streamer in a frequency band of 10 Hz–1 kHz on the towing speed in a range of 1 to 5 knots, on the coefficient of relative elongation of its elastic section, its type, and on the type of attachment of the elastic section to the towed body have been studied. In addition, the dependence of the tensile load on the studied streamer on the towing speed is obtained. The experimental data obtained during field tests on the streamer noise level and their analysis are presented. The reduction of the towing noise level when using an elastic section occurred by a factor of up to 3 in a frequency range of 180 to 600 Hz depending on the type of elastic section when attaching it to a strength member of the towed body, and up to 2 in the entire studied frequency range.

The propagation features and critical conditions of low-velocity detonation (LVD) in the high-density charges of finely dispersed ammonium perchlorate (APC) mixtures with combustible and explosive additives are studied. The effect of the relative charge density, the combustible component type, and the ratio of mixture components, including the mixtures strongly enriched with a combustible agent, on the propagation of detonation is considered. It is shown that the dependence of the detonation velocity on the relative charge density in the case of APC mixtures with combustible additives has a plateau-like region, in which the detonation velocity is at a level of 2000 m/s and is practically independent of the density and nature of the combustible component. Moreover, the critical charge density, above which the failure of LVD is observed, is revealed. In the case of ternary mixtures with a liquid explosive (nitromethane) additive, there is no similar dependence, and the detonation velocity monotonically grows with an increase in the relative density. The critical initiation pressures of compositions are also determined within the density range, where the density has no effect on the detonation velocity. The performed studies make it possible to refine the composition and characteristics of high-density mixtures, for which the application of LVD regimes can ensure the creation of efficient explosion-proof impulse devices.

Purpose of the study is improving the mechanism of state regulation of agricultural producers, due to the need to overcome the pandemic and prevent the recurrence of similar scenarios in the future. The object of research is an agricultural producer, belonging to the category of small business. The subject of the study is the relationship between the object of study and the state represented by government bodies and institutions involved in the provision of state support that may arise in the process of overcoming the consequences of the COVID-19 pandemic. Research Methods. A theoretical analysis was used to identify threats from the coronavirus pandemic to agriculture and the agro-industrial complex as a whole. Comparison as a method of cognition was used when comparing the requirements of small businesses for state support and measures actually taken by the government. A systematic approach and modeling were used to summarize the experience of the functioning of the economy in a pandemic and to create patterns of behavior of small agribusiness entities. The method of scientific abstraction made it possible to present the most probable state of small business in the agro-industrial complex, depending on the provision or refusal of state regulatory influence on the economy in order to eliminate the damage caused by the pandemic. The rule of combining historical and logical in their unity allowed us to look at the coronavirus pandemic not as a unique phenomenon in the history of modern economics, but as a negative phenomenon that will potentially be reproduced in the future and the logic of counteraction which requires active intervention at the state level, and in the future - generalization, analysis and improvement of the experience gained. The theoretical and methodological basis of the study is composed of statistical data on the state of the world economy, consumption, unemployment, publications of news agencies and government officials on measures taken to deal with the consequences of the pandemic, existing programs for the development of the digital economy, as well as publications of leading scientists in the agricultural sector on digital problems economics. Results. Within the scope of this study, there were characterized the most negative consequences of the pandemic for the agro-industrial complex, there was carried out the analysis of announced and already taken measures to support entrepreneurship and were described behavior models of small agribusiness entities in the current situation. Scientific novelty. The authors have developed a new method for the rapid diagnosis of a small agribusiness subject, claiming to receive state support for regional and industry programs.

All published to date experimental wavenumber values (ν, cm–1) for electronic-vibro-rotational transitions of the H2 molecule are statistically analyzed in the vacuum wavelength range 1/ν = 600—610 nm. It is shown that a direct comparison of all datasets of various authors is blocked by the absence of deconvolving of measured spectra, blending of neighbor lines (an overlap of their profiles), and fragmentary data of most studies. Therefore, it is proposed to compare all available data with the dispersion curve of a high-resolution spectrometer by measuring and deconvolving the H2 spectra. An experimental study of such an opportunity showed that the proposed approach makes it possible not only to analyze the scatter of available data on 1/ν and ν (standard deviations are about 0.003 nm and 0.08 cm–1), but also to obtain more reliable datasets with uncertainties (95% confidence intervals) less than 0.0006 nm and 0.02 cm–1 respectively.

Satellite data on methane concentration in the lower troposphere and the dynamical permafrost model are used to analyze methane emissions in the permafrost zone. The sources of methane generation in different biochemical conditions in the river valleys, thermokarst lakes, wetlands, and lowlands are studied. The statistical relationships between their intensity and air temperature, precipitation, active layer thickness, and permafrost temperature are evaluated. The CMIP5 ensemble climate projection is used to estimate methane emission in the permafrost regions for the mid-21st century. Numerical experiments with the INM-CM48 Earth system model demonstrated that the projected 20 Tg/year increase in the methane emission will lead to less than 0.05°C global temperature rise. The uncertainty analysis of the results is accomplished and an alternative conceptual model of abrupt threshold changes in methane emission is proposed.

The computational setup of assimilation and reanalysis of measurement data on temperature of the upper ground layer and active layer thickness based on the models of various complexity is formulated. A need in applying a dynamic model for this purpose is substantiated. Four types of permafrost with different active layer thickness are distinguished. The model validation based on measurement data in northern European Russia and Eastern Siberia is carried out for these permafrost types. A method for taking into account the small-scale variability of soil, vegetation, and landscape factors based on the ensemble simulations is proposed. It is shown that the dynamic model simulates well measurement data on the active layer thickness for a wide range of landscape, soil, and climate conditions and can be used for the reanalysis of permafrost data.

An ordered graph is a simple graph with an ordering on its vertices. Define the ordered path P n to be the monotone increasing path with n edges. The ordered size Ramsey number r ( P r , P s ) is the minimum number m for which there exists an ordered graph H with m edges such that every two-coloring of the edges of H contains a red copy of P r or a blue copy of P s . For 2 ≤ r ≤ s , we show 1 8 r 2 s ≤ r ( P r , P s ) ≤ C r 2 s ( log s ) 3 , where C > 0 is an absolute constant. This problem is motivated by the recent results of Bucic et al. (2019) and Letzter and Sudakov (2019) for oriented graphs.

In this paper we present an experimental study of the electron transport in composite samples based on an insulating matrix of polybenzimidazole with graphite nanoparticles as conducting filler. Based on a qualitative analysis of the temperature dependences of electrical resistance obtained for the samples with different filler concentrations, it was established that the electron transport occurred mostly by tunneling between conducting filler particles, with variable-range hopping conduction taking place at low temperatures.

The article describes fossil remains of two spiral-horned antelope species Gazellospira torticornis (Aymard, 1854) and Pontoceros ambiguus Vereschagin, Alexejeva, David et Baigusheva, 1971 which were found in 2018 in the Lower Pleistocene sediments of the Taurida Cave in Central Crimea. These finds are the first evidence of the occurrence of these taxa on the Crimean Peninsula. This association is correlated with the Late Villafranchian faunas of Europe and the mammal zone MNQ18 (within the time interval 1.8–1.5 Ma). Fossils of G. torticornis from the Taurida Cave confirm the tendency towards a reduction in size among the late representatives of this antelope species. P. ambiguus from the Taurida Cave is one of the earliest representatives of the species in the south of Europe. Finds of spiral-horned antelopes in the Taurida Cave help elucidate the details of their morphological evolution, refine their geographic and stratigraphic range.

The results of investigations of the complexation of N-vinylsuccinimide (VSI) in monomer–solvent and monomer–monomer systems and the effect of these processes on the kinetics of copolymerization of VSI with monometers of differing reactivity are summarized. Conditions for the synthesis of compositionally homogeneous copolymers were established. Taking into account the electronic structure of VSI and co-components, a mechanism of complexation in VSI–dimethylsulfoxide, VSI–acetic anhydride, and VSI–maleic anhydride systems is proposed. The electron density redistribution in the VSI molecule upon complexation has been quantitatively assessed.

BackgroundTissues of multicellular animals are maintained due to a tight balance between cell proliferation and programmed cell death. Phylum Porifera is an early branching group of metazoans essential to understanding the key mechanisms of tissue homeostasis. This paper is dedicated to the comparative analysis of proliferation and apoptosis in intact tissues of two sponges belonging to distinct Porifera lineages, Halisarca dujardinii (class Demospongiae) and Leucosolenia variabilis (class Calcarea).ResultsLabeled nucleotides EdU and anti-phosphorylated histone 3 antibodies reveal a considerable number of cycling cells in intact tissues of both species. The main type of cycling cells are choanocytes - flagellated cells of the aquiferous system. The rate of proliferation remains constant in areas containing choanoderm. Cell cycle distribution assessed by the quantitative DNA stain reveals the classic cell cycle distribution curve. During EdU pulse-chase experiments conducted in H. dujardinii, the contribution of the choanocytes to the total amount of EdU-positive cells decreases, while contribution of the mesohyl cells increases. These findings could indicate that the proliferation of the choanocytes is not solely limited to the renewal of the choanoderm, and that choanocytes may participate in the general cell turnover through migration. The number of apoptotic cells in intact tissues of both species is insignificant. In vivo studies in both species with TMRE and CellEvent Caspase-3/7 indicate that apoptosis might be independent of mitochondrial outer membrane permeabilization.ConclusionsA combination of confocal laser scanning microscopy and flow cytometry provides a quantitative description of cell turnover in intact sponge tissues. Intact tissues of H. dujardinii (Demospongiae) and L. variabilis (Calcarea) are highly proliferative, indicating either high rates of growth or cell turnover. Although the number of apoptotic cells is low, apoptosis could still be involved in the regular cell turnover.

A series of bis-amides of bis(aminoalkyl)benzenes and diaminoalkanes were synthesized. Positive modulation of kainate-induced transmembrane currents was registered on Purkinje neurons for isobutyric acid derivative with 1,4-bis(aminomethyl)benzene linker (40% potentiation at 1 nm). This compound also demonstrated a neuroprotective effect at 0.1 nm in an oxidative stress model in HT-22 cells when applied 24 h before H2O2.

The results of experimental studies on the kinetics of copolymerization of 2-hydroxyethyl methacrylate with acrylic acid in water and propanol are generalized. The effect of the polarity of the medium on the relative activity of monomers and the microstructure of the obtained copolymers is analyzed.

Heterogeneous architectures and heterogeneous-ISA designs are growing areas of computer architecture and system software research. Unfortunately, this line of research is significantly hindered by the lack of experimental systems and modifiable hardware frameworks. This work proposes BYOC, a "Bring Your Own Core" framework that is specifically designed to enable heterogeneous-ISA and heterogeneous system research. BYOC is an open-source hardware framework that provides a scalable cache coherence system, that includes out-of-the-box support for four different ISAs (RISC-V 32-bit, RISC-V 64-bit, x86, and SPARCv9) and has been connected to ten different cores. The framework also supports multiple loosely coupled accelerators and is a fully working system supporting SMP Linux. The Transaction-Response Interface (TRI) introduced with BYOC has been specifically designed to make it easy to add in new cores with new ISAs and memory interfaces. This work demonstrates multiple multi-ISA designs running on FPGA and characterises the communication costs. This work describes many of the architectural design trade-offs for building such a flexible system. BYOC is well suited to be the premiere platform for heterogeneous-ISA architecture, system software, and compiler research.

Synthesis of 6-[4-methoxy-3-(pyrrolidin-1-ylmethyl)benzyl]-1,11-dimethyl-3,6,9-triazatricyclo[7.3.1.13,11]tetradecane-4,8,12-trione has been carried out and optimized. In vitro studies using electrophysiological patch clamp technique have revealed a negative effect of this compound on kainateinduced currents in Purkinje neurons in a wide range of concentrations from 10−11 to 10−6 m.

При изучении калибровочно-инвариантной перенормируемости четырехмерной теории Янга-Миллса с использованием метода фонового поля и БВ-формализма выведено однородное (относительно антискобки) классическое мастер-уравнение с помощью введения антиполевых партнеров к фоновым полям и параметрам. Построенную модель можно перенормировать стандартным методом введения контрчленов. Она не обладает (строгой) мультипликативной перенормируемостью, но обладает ей в физическом секторе (квазимультипликативная перенормируемость).

A Rhodococcus rhodochrous strain, M33-2nit, has been constructed with two copies of the nitrilase gene from A. denitrificans В-9582 under the control of nitrile hydratase promoter from R. rhodochrous M8. The optimized cultivation of this strain made it possible to obtain the enzyme in a concentration of up to 17 g of dry cells/L with a specific activity of up to 7 U/mg cdw with a two-substrate culturing scheme in a fed-batch reactor with the sequential addition of glucose and acetate. The capacities of A. denitriificans В-9582 and R. rhodochrous M33-2nit cells to synthesize ammonium acrylate from acrylonitrile under conditions imitating industrial synthesis are compared. It is shown that R rhodochrous M33-2nit cells can synthesize ammonium acrylate under higher rates of acrylonitrile feeding than A. denitriificans В-9582 cells. The potential to obtain a highly concentrated solution of ammonium acrylate (450 g/L) with R. rhodochrous M33-2nit cells as a biocatalyst was demonstrated. The conversion of acrylonitrile to ammonium acrylate reached 99.5%.

Industry is building larger, more complex, manycore processors on the back of strong institutional knowledge, but academic projects face difficulties in replicating that scale. To alleviate these difficulties and to develop and share knowledge, the community needs open architecture frameworks for simulation, chip design, and software exploration that support extensibility, scalability, and configurability, alongside an established base of verification tools and supported software. In this article, we present OpenPiton, an open source framework for building scalable architecture research prototypes from one core to 500 million cores. OpenPiton is the world's first open source, general-purpose, multithreaded manycore processor, and framework. OpenPiton is highly configurable, providing a rich design space spanning a variety of hardware parameters that researchers can change. OpenPiton designs can be emulated on FPGAs, where they can run full-stack multiuser Debian Linux. OpenPiton is designed to scale to very large core fabrics, enabling researchers to measure operating system, compiler, and software scalability. The mature code-base reflects the complexity of an industrial-grade design and provides the necessary scripts to build new chips, making OpenPiton a natural choice for computer-aided design (CAD) research. OpenPiton has been validated with a 25-core chip prototype, named Piton, and is bolstered by a validation suite that has thousands of tests, providing an environment to test new hardware designs while verifying the correctness of the whole system. OpenPiton is being actively used in research both internally to Princeton and in the wider community, as well as being adopted in education, industry, and government settings.

The problems of improving the structure and mode of green zones use in cities are considered. Insufficient coordination of the urban planning principles, urban ecology and nature protection causes these problems. The methods of forestry, urban ecology, landscape ecology and erosion, principles of comparative and gradient analyzes have been applied. The influence of human activity on recreational and health, protective and nature conservation stands is investigated using the example of an inner green zone in Uman (Ukraine). This article establishes the extend, the diagnostic and spatial peculiarities of their disturbance depending on their functional purpose, forestry and taxation characteristics, location in the landscape, relative to the objects of communication and to attractive centers of flock and people rest. It has been found that Sofiyivka Arboretum had undergone mechanical and fire damage trees, weed invasion, trampling vegetation and soil cover in the areas of the most attractive sites. This leads to surface and vertical soil erosion on the steep slopes. However, the most degraded soil and water protection plantations are in attractive places of the city river coastal protective strip. Near the cemetery with the Hasid spiritual master tomb, Quercus robur plantation is intensely clogged and trampled. One third of the trees have mechanical damages, more than 14 % are damaged by fire. The stands in the edge lane above the River Umanka flood bed begin to degrade. It can activate the ravine system developed in the past. The ravines are grown over with grass stand. The dissection degree with ravines of the territory is 26.9 m/ha. The largest ravine reaches a length of 188 m, an area of 0.58 h, a depth of more than 8 m and has 14 deep partings. The protective plantation located in the suburbs is less degraded. The plantations near reservoirs, around picnic areas are medium and intensively damaged. They are being cut down somewhere. This led to the activation of soil erosion. Therefore, it is necessary to improve the organization of recreation areas and to regulate their visiting in Uman, taking into account landscape and ecological, urban, and environmental standards. Preserving priority functions of protective green plantations is necessary.

In this review our recent results on the electron-beam domain writing (EBDW) on the nonpolar surfaces of LiNbO3 crystals of different compositions are presented. The obtained results permitted us to relate the main characteristics of domain formation (the domain sizes and velocity Vf of the frontal motion) to the irradiation conditions (the accelerating voltage U of scanning electron microscopy, EB-current I, the inserted charge Q). The domain depth Td is controlled by U via the electron penetration depth; the domain length Ld increases linearly with Q owing to the domain frontal growth by the viscous friction law. In optical waveguides, the matching of the Td value with the waveguide thickness D provides optimal values of the waveguide conversion to the second harmonic

The aim of this study was to examine in vitro the antioxidant and antiviral activity of echinochrome A and echinochrome-based antioxidant composition against tick-borne encephalitis virus (TBEV) and herpes simplex virus type 1 (HSV-1). Materials and methods. TBEV (Dal’negorsk strain, Far Eastern subtype) grown in PK cells, and HSV-1 (VR3 strain) in Vero cells. The antioxidant activity of the compounds was determined using the linetol peroxide oxidation model. The cytotoxicity and antiviral activity of the compounds were assessed by cell viability (PK- and Vero cells) and by cytopathic effect inhibition of viruses (TBEV and HSV-1) using the MTT test. Results. The antioxidant composition, which is a mixture of echinochrome A, ascorbic acid and α-tocopherol (5: 5: 1), showed a higher antioxidant and antiviral efficacy than echinochrome A. The antiviral mechanisms on of echinochrome A and antioxidant composition are caused by direct inactivation of TBEV and HSV-1 viruses and inhibition of virus penetration into cells. Conclusion. The results obtained allow considering the echinochrome A and the composition of antioxidants on its basis as the promising agents of a broad-spectrum antiviral activity.

Using the background field method for the functional renormalization group approach in the case of a generic gauge theory, we study the background field symmetry and gauge dependence of the background average effective action, when the regulator action depends on external fields. The final result is that the symmetry of the average effective action can be maintained for a wide class of regulator functions, but in all cases the dependence of the gauge fixing remains on-shell. The Yang-Mills theory is considered as the main particular example., Comment: Fits the version accepted in EPJC

The results of the experimental studies of underwater explosions of ideal and nonideal detonating charges in continuous water and water-containing air bubbles are presented. Charges weighing up to 50 g are exploded in a metal reservoir filled with water. The parameters of the compression waves in the water are recorded. The effect of the directional propagation of the shock wave in the water along the channel filled with air bubbles is shown. The mechanism of nonideal explosions of highly metallized compositions in water, including explosions in a bubble medium, is also discussed.

A new species of Hyaenodontinae is described from a horizontal ramus of the mandible, the smallest Asian species of the subfamily, Hyaenodon pumilus sp. nov. from the upper Eocene of the Ergilin Dzo Formation of southwestern Mongolia. New specimens of H. chunkhtensis Dashzeveg, 1985 are described from the localities Khoer Dzan (Ergilin Dzo Formation, upper Eocene) and Tatal Gol (Shand Gol Formation, upper Oligocene). The specimens of H. chunkhtensis can be divided into two morphotypes.

Fiber-optic interferometric sensing is a very attractive approach for creating lightweight, high-sensitive, and fully passive fiber-optic hydrophone arrays. In this paper, results of sea trials of the thin cable fiber-optic hydrophone array for passive acoustic surveillance applications are presented. The performed trials consisted of two parts: the first part was devoted to the estimation of the array acoustic performance and the second part included the direction of arrival (DOA) estimation of the moving acoustic source. The estimation of the array acoustic performance showed that the average measured pressure sensitivity of fiber-optic hydrophones increased as the acoustic frequency increased from −122 dB re rad/ $ {\mu }$ Pa at 20 Hz to −116 dB re rad/ ${\mu }$ Pa at 495 Hz. The average minimum detectable pressure of hydrophones decreased from 78, 1 dB re $1~{\mu }$ Pa at 20 Hz to 28, 5 dB re $1~{\mu }$ Pa at 495 Hz. Obtained values of the minimum detectable pressure were below the sea state zero noise level in the considered frequency range. The average dynamic range of fiber-optic hydrophones was above 120 dB at 495 Hz. The proper capability of the DOA estimation was successfully demonstrated using the motor boat as the moving acoustic source. Trajectories of the moving boat were obtained by using the beamscan DOA estimation algorithm with additional Kalman filtering. Obtained results demonstrated the great potential of using fiber-optic interferometric sensors for hydroacoustic surveillance applications. The presented results might be helpful for the implementation of extended fiber-optic hydroacoustic surveillance systems.

The tribotechnical properties of unfilled and dispersed-filled epoxy polymers were studied. The coefficients of sliding friction and the wear rates of polymer composite materials were determined. The dependence of coefficient of sliding friction on type of filler and its content in the polymer composition was studied. The fabricated composite materials were tested for abrasion resistance against steel.

The kinetics of ammonia ligation to atomic first and second row transition metal cations were measured in an attempt to assess the role of ligand field effects in gas-phase ion-molecule reaction kinetics. Measurements were performed at 295 ± 2 K in helium bath gas at 0.35 Torr using an inductively coupled plasma/selected-ion flow tube tandem mass spectrometer. The atomic cations were produced at ca. 5500 K in an inductively coupled plasma source and were allowed to decay radiatively and to thermalize by collisions with argon and helium atoms prior to reaction. A strong correlation was observed across the periodic table between the measured rate coefficients for ammonia ligation and measured/calculated bond dissociation energies. A similar strong correlation is seen with the ligand field stabilization energy. So ligand field stabilization energies should provide a useful predictor of relative rates of ligation of atomic metal ions.

Here we present the results of the exciton states study in WSe2 and MoS2 monolayers. Thin WSe2 and MoS2 films obtained by CVD technique were studied by optical methods. The films two-dimensionality and homogeneity were confirmed by the methods of atomic force microscopy and luminescence spectroscopy. The second harmonic generation (SHG) spectroscopy technique was used for the exciton states study at room temperature in the pump photon energy range of 0.8-1.05 eV. The sevenfold SHG intensity resonance amplification was found for the 1.62 eV and 1.87 eV SHG photon energy for the WSe2 and MoS2 films, respectively, that corresponds to the exciton transition energy. These resonance peaks belong to optical A excitons with 1s energy level.

The kinetics of H2 elimination and ligation of ammonia reacting with early atomic transition metal cations and ensuing ammonia ligation reactions were measured across (Groups 3–9) and down (the three rows) the periodic table. The atomic cations were produced in an Inductively Coupled Plasma (ICP) source at ca. 5500 K and allowed to decay radiatively and to thermalize by collisions with argon and helium atoms prior to reaction. Kinetic measurements were performed using an ICP/Selected-Ion Flow Tube (ICP/SIFT) tandem mass spectrometer with helium bath gas at 0.35 Torr and 295 ± 2 K. Our survey showed that bimolecular H2 elimination to produce MNH+ predominated with very early atomic transition metal cations: M+ = Sc+ and Ti+ in the first row, Y+, Zr+ and Nb+ in the second row, and La+, Hf+, Ta+, W+, Os+ and Ir+ in the third row. The remaining atomic transition metal cations were observed to ligate ammonia (with He acting as a third body): M+ = V+, Cr+, Mn+, Fe+ and Co+ in the first row, Mo+, Ru+ and Rh+ in the second row, and Re+ and Ir+ in the third row. Higher order ligation reactions were observed with M+ to form M+(NH3)n with n up to 6 and MNH+(NH3)n with n up to 3. Experiments with three of the 3rd row MNH+ cations (M = Ta+, W+ and Os+) revealed the rapid formation of a second imido bond to produce M(NH)2+ followed by ammonia ligation. Variations in the occurrence of imido bond formation and the extent of ligation and trends in measured rate coefficients are scrutinized across and down the periodic table in terms of available theoretical computations of potential energy surfaces as well as atomic orbital filling effects.

Bonding between cement and steel is currently believed to be of key importance in well integrity since it prevents the development of microannulus. Push-out test is often used to quantify the bonding strength between cement and steel in laboratory. Our experiments reveal a strong size-dependency of the push-out strength measured in these tests: the strength decreases with pipe diameter. This means that the push-out strength is not an intrinsic material parameter ("bonding strength") and therefore cannot be applied to field conditions before a proper correction is introduced. Such correction should take into account the large difference in diameter between the casing and the pipes typically used in laboratory tests. Finite-element simulations show that the experimentally-observed size-dependency could be, at least partially, explained by cement shrinkage that creates initial normal stress at the interface. The observed push-out strength is then not an intrinsic property of the interface between two materials (which would be an adhesive shear strength) but rather a result of interfacial friction. As the pipe diameter increases, the shrinkage-induced normal stress at the interface decreases, the frictional resistance decreases, and thus the measured push-out strength decreases, too, as observed in the lab tests. Simulations show, however, that shrinkage-induced decrease in push-out strength cannot fully explain the size-dependency since the decrease is much larger in the experiments than in the simulations. Another mechanism that could be at play is the common size effect: interfaces become weaker as their size increases because it is more likely that a larger interface contains an initial flaw of a given size. The decrease of push-out strength with pipe diameter has at least two practical implications: (i) the concept of bonding strength is misleading (unless it is specified explicitly that this parameter refers to frictional resistance at the interface rather than to an inherent adhesive strength) and (ii) the results of push-out tests can be used in well design only if a proper correction for the pipe diameter is introduced.

The results of experimental studies on copolymerization kinetics of 2-hydroxyethyl methacrylate with carboxyl-containing monomers of acrylic, methacrylic, and maleic acids in water using the redox initiator system of ammonium persulfate–ascorbic acid are summarized. The effect of process conditions on the reaction rate, relative activity of monomers, composition, and microstructure of copolymers is analyzed.

The phenomenon of whole-body regeneration means rebuilding of the whole body of an animal from a small fragment or even a group of cells. In this process, the old axial relationships are often lost, and new ones are established. An amazing model for studying this process is sponges, some of which are able to regenerate into a definitive organism after dissociation into cells. We hypothesized that during the development of cell aggregates, primmorphs, new axes are established due to the activation of the Wnt and TGF-beta signaling pathways. Using in silico analysis, RNA-seq, and whole-mount in situ hybridization, we identified the participants in these signaling pathways and determined the spatiotemporal changes in their expression in demosponge Halisarca dujardinii. It was shown that Wnt and TGF-beta ligands are differentially expressed during primmorph development, and transcripts of several genes are localized at the poles of primmorphs, in the form of a gradient. We suppose that the Wnt and TGF-beta signaling cascades are involved in the initial axial patterning of the sponge body, which develops from cells after dissociation.