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Objectives. To develop a technology for obtaining recombinant antibodies in a suspension culture of human HEK293 cells using transduction with recombinant adenovirus serotype 5 (rAd5) carrying genes expressing heavy and light chains of antibodies on the example of two broadspectrum anti-influenza antibodies 27F3 and CR9114.Methods. Ad5-27F3-H, Ad5-CR9114-H, and Ad5-27F3-L recombinant adenoviruses carrying the 27F3 antibody heavy chain gene, CR9114 antibody heavy chain gene, and 27F3 light chain gene, respectively, were generated using the AdEasy™ Adenoviral vector system. To accumulate preparative amounts of recombinant r27F3 and rCR9114 antibodies, the HEK293 suspension cell line was transduced with recombinant adenoviruses carrying genes for heavy and light chains of antibodies. The cells were cultured in a wave-type bioreactor. Chromatography was used to purify recombinant antibodies from the culture medium. After analyzing the molecular weights of purified antibodies using protein electrophoresis, their ability to interact with influenza A and B viruses was analyzed using the Western blot technique, while their ability to neutralize influenza A and B viruses was evaluated using the virus neutralization assay.Results. A method for the accumulation and purification of recombinant r27F3 and CR9114 antibodies from the culture medium of a suspension culture of human cells following transduction with its recombinant adenoviruses carrying the genes for heavy and light chains of these antibodies was developed. The ability of the r27F3 antibody to interact with and neutralize influenza A viruses of group 1 (except influenza A virus subtype H2) and group 2 was shown. The ability of the rCR9114 antibody to interact with influenza A viruses of group 1 and influenza B viruses, as well as to neutralize influenza A viruses of group 1, was demonstrated.Conclusions. A technology for obtaining recombinant antibodies in a suspension culture of HEK293 cells using transduction with recombinant adenoviruses carrying genes expressing heavy and light chains of antibodies was developed along with a confirmation of their specificity.

A new platform for creating anti-coronavirus epitope vaccines has been developed. Two loop-like epitopes with lengths of 22 and 42 amino acid residues were selected from the receptor-binding motif of the Spike protein from the SARS‑CoV‑2 virus that participate in a large number of protein-protein interactions in the complexes with ACE2 and neutralizing antibodies. Two types of hybrid proteins, including one of the two selected epitopes, were constructed. To fix conformation of the selected epitopes, an approach using protein scaffolds was used. The homologue of Rop protein from the Escherichia coli ColE1 plasmid containing helix-turn-helix motif was used as an epitope scaffold for the convergence of C- and N-termini of the loop-like epitopes. Loop epitopes were inserted into the turn region. The conformation was additionally fixed by a disulfide bond formed between the cysteine residues present within the epitopes. For the purpose of multimerization, either aldolase from Thermotoga maritima, which forms a trimer in solution, or alpha-helical trimerizer of the Spike protein from SARS‑CoV‑2, was attached to the epitopes incorporated into the Rop-like protein. To enable purification on the heparin-containing sorbents, a short fragment from the heparin-binding hemagglutinin of Mycobacterium tuberculosis was inserted at the C-terminus of the hybrid proteins. All the obtained proteins demonstrated high level of immunogenicity after triplicate parenteral administration to mice. Sera from the mice immunized with both aldolase-based hybrid proteins and the Spike protein SARS‑CoV‑2 trimerizer-based protein with a longer epitope interacted with both the inactivated SARS‑CoV‑2 virus and the Spike protein receptor-binding domain at high titers. Supplementary information The online version contains supplementary material available at 10.1134/S0006297921100096.

The current composition of horsefly species in Pskov Province and their associations with different biotopes in the province and in the whole of Northwest of European Russia are analyzed. A zoning system of the hydrolandscapes of Pskov Province with regard to the factors affecting the distribution of horsefly species is proposed for the first time.

We studied the seasonal dynamics of flight activity in horseflies (Diptera, Tabanidae) belonging to 30 species from 6 genera. The results show that the abundance of horseflies is largely controlled by abiotic factors, such as temperature and relative humidity. Horseflies start their flight activity at an air temperature not lower than +15°C and relative humidity not lower than 57%. There are species-specific differences in the seasonal pattern of activity. Depending on the season when activity commences, the horseflies studied can be divided into spring species (end of May), early summer species (beginning of June), and summer species (beginning of July). We attribute this variation in the timing of adult emergence to different temperature and humidity optima for larval and pupal development in different horsefly species. A routine is proposed for estimating the long-term seasonal dynamics of flight activity of horseflies with the use of weekly and monthly mean temperatures, relative air humidity, and the sum of degree-days. In a similar manner, the flight activity pattern can be projected into the future.

Three-dimensional simulation of the motion of a multibeam electron flow in high power multibeam klystrons for high values of the efficiency (70 $$\%$$ and higher) is necessary. The value of the efficiency calculated earlier in terms of the one-dimensional and two-dimensional models only for one partial beam is higher than that experimentally measured, usually by 10–15 $$\%$$ of the absolute value. An increase in the number of partial beams and a transversely developed configuration of ring cavities (an ‘‘oversized’’ cavity), as a rule, lead to an increase in the inhomogeneity of the microwave field distribution along the drift tubes of the ring cavity and generate a phase difference of microwave fields (phase incursions). It is shown here that energy extraction even from identical electron bunches of a multibeam flow depends on the location of the partial drift tube relative to the energy output. The use of the BAC method of electron bunching can increase the efficiency of klystrons. The results of 3D simulation of the interaction of a multibeam electron flow in the output ring cavity of a BAC-klystron with an output pulse power of 6 MW have made it possible to estimate quantitatively the influence of the phase incursions of the waves. It has been shown that the phase difference of the microwave fields in the output cavity significantly reduces the interaction efficiency and, consequently, the efficiency of multibeam klystrons. Thus, the phase delay of the waves excited in different drifts tubes of the gap of an ‘‘oversized’’ output ring cavity is one of the physical reasons for limitation of the efficiency of multibeam klystrons.

The object of research is an optical-electronic system for detecting aircraft. The subject of the research is methods for selecting a moving object on a complex inhomogeneous background. The purpose of this work is to develop an algorithm for detecting an unmanned aerial vehicle by an optoelectronic system on a non-uniform background in real time. The presented studies were performed using video image processing methods. A noise-resistant method for selecting an unmanned aerial vehicle against a complex dynamic background is proposed. The algorithm is based on calculating the coordinates of the center of the object area by finding the Gaussian adaptive threshold of the background image. The proposed method can be used in the development of an optical-electronic system for detecting a moving unmanned aerial vehicle against a non-uniform background in real time in the infrared range. As a result, it was found that the proposed algorithm confidently copes with the detection of a contrasting object located at a distance of up to 2 km from the detection system.

This article discusses the theoretical core and evolution of Ruben Apressyan’s moral philosophy. The starting point in the development of his views was his clarification of the “idea of morality,” ...

The results of the approach to predicting RTS index futures based on linear and polynomial regression are presented. Two modifications of the proposed algorithm are described. Based on the analysis of the obtained results some recommendations and conclusions are made on using of the developed approach. Also presented in the paper is an overview of the most popular stock market prediction methods based on machine learning as well as the results of their usage.

The results of a study of the kinetics and mechanism of heterogeneous and compact ceramics oxidation in the ZrSi2-MoSi2-ZrB2 system at air temperature of 1400 °C are presented. The ceramics were obtained by the hot-pressing of composite powders that were manufactured by self-propagating high-temperature synthesis following the magnesiothermal recovery approach. Oxidation kinetics are described using a power function with index n > 2 , confirming the significant influence on the evolution process in the structure of the formed oxidation coating. The oxidation mechanism includes the formation of a two-layer structure consisting of a continuous silicate film, of which the outer part contains magnesium and a sublayer based on the ZrSiO4 phase, with the scheelite structure encapsulating the ZrB2 and MoSi2 grains. The influence of the ZrSi2, MoSi2 and ZrB2 phases on the structural-morphological peculiarities of the appearing oxide films and the effectiveness of its protective action are revealed.

The authors studied the effect of key parameters of detonation spraying process on tungsten carbidebased coatings and their mechanical properties, microstructure, and phase composition. Two main tasks are solved when developing the technology for spraying the carbide-containing materials. The relationship is established between the phase composition of tungsten-based coatings and their strength, hardness, and substrate adhesion. It was established that the WC dissolution in the metal phase promotes the increase of substrate adhesion as well as strength and hardness of coating material. A procedure of spraying coatings in the reduction mode is proposed: i.e., using working gas mixtures with excess acetylene. It prevents the decarbonization of WC carbides under the action of detonation products and environment. The phase composition heterogeneity (both along with the layer thickness and along the spraying spot diameter) is established. This depends on a complex of factors that determine the intensity of heat removal from the area of layer formation. For optimizing the structure and the mechanical characteristics of the coating, we need to control decarbonization of carbide component (WC) and formation of Ni (W) solid solution at different stages of spraying. Even a minor departure from carbon content leads to either appearance of graphite or formation of the fragile phase (Co3W3C), thus strongly reducing the mechanical properties.

The physicochemical interaction in the ZrSi2–ZrSiO4 system at temperatures higher than 1620°C under the conditions of molecular oxygen deficiency is established and experimentally confirmed. Elemental silicon is reduced simultaneously with the oxidation of zirconium to the thermodynamically stable ZrO2 phase. The mechanism and steps of the interaction processes are proposed.

Using the Fresnel reflection geometry and a fiber optic probe, a strong effect of interrogating light intensity on an effective refractive index of ferrofluid placed in magnetic field was observed and measured. With a moderate level of light power from 0.5 mW to 135 mW, an effective refractive index of kerosene-based ferrofluid was increasing with rising of light power by more than 4% at the same strength of magnetic field. It is important to note, no such dependence was observed without magnetic field applied. Also, influence of light power on dynamics of optical response on magnetic field impulse was observed.

The kinetics and mechanism of high-temperature oxidation of dense heterophase ZrSi2-MoSi2-ZrB2 ceramics at a temperature of 1650 °C are studied. The ceramics were fabricated by hot pressing of composite powders prepared by self-propagating high-temperature synthesis with magnesiothermic reduction. The oxidation kinetic curve is described by the power-law function, which indicates that the evolutionary changes in the structure of the formed oxide films significantly affect the course of the oxidation process. The oxidation mechanism involves formation of a multi-layered structure of heterogeneous oxide film, partial dissociation of the ZrSiO4 phase, and formation of secondary MoB and Mo5Si3 compounds. The influence of the ZrSi2, MoSi2 and ZrB2 phases on the structural and morphological features of the formed oxide films and the efficiency of their protective action are shown. Silicon is reduced and zirconium is simultaneously oxidized to ZrO2 in the ZrSi2-ZrSiO4 system at temperatures above 1620 °C in the absence of oxygen or in low-oxygen environment.

When operating technically complex objects, the accidents and emergencies occurring at them should be forecasted. Such a forecast can be made by analyzing the technical state of an object. The variety of technical states of technically complex objects forms a set of emergency variables indicating the onset of a change in the TCO’s technical state – an emergency. The technical state of an object can often be characterized based on the physical process parameters recorded by sensors mounted on the object. The time series obtained by converting sensor data on a technically complex object is often short due to the nature of the impact on this TCO. Forecasting by studying a short time series becomes possible through analyzing information on the series structure patterns. There is an issue of detecting a change in the technically complex object state, which is expressed as a change in the variance of the residual component of a short time series formed by the sensor output values read with a uniform pitch (residuals, disturbances, noises). This issue cannot always be solved by visual monitoring of the sensor readings for technical (high speed of the processes) and psychological (visual effects, different interpretations of the same plots by experts) reasons. One of the tools for analyzing TSs of this size are techniques used to detect structural heterogeneity – the heteroscedasticity tests.

There are schematic solutions in electrical measurements and communication technique when information is transmitted in the form of duration of a time interval specified by a rectangular pulse. The reasons for the appearance of additive noise effecting the pulse duration are numerous and cannot be completely eliminated. These are caused not only by electromagnetic interference in the environment, but also by limitations in the characteristics of the electronic components of any operating principle including fiber optic transmission lines. The restrictions imposed by the noise on the accuracy of a time interval allocation were considered in this article. The additive model of the data signal and centered noise acting together upon the pulse shaper input are considered in the article. It is assumed in the model that the shaper conversion function is characterized by hysteresis that protects against false actuating. Some relationships between the distribution law form of the shaper response time, data signal form and noise statistical characteristics are revealed. It is obtained that moments of a shaper actuating are complied with the truncated Gaussian law. The time interval error is evaluated for cases when the front and slice of the pulse are determined by the moments of action of one shaper or some shaper with different noise statistical characteristics.

This paper is devoted to finding a relationship between harmonic interference on a data transfer and the pulse duration errors in transmitting an informative signal. Looking for a noise immunity in the case of pulse-width modulation makes sense if we can’t rely upon fiber-optic channels and other stationary equipment only. Surging interferences on a channel transmitting a pulse modulated signal result in a jitter on the leading and falling edges of the pulses. If the noise influence can’t be eliminated, a data transfer errors occur, inherent to the pulse-width modulation and other kinds of pulse modulation. At the time of making the paper, the authors were exploring a rationale for how the time lapse fixing errors are dependent on harmonic interference parameters. Here we give a grounding for the rule of the distribution law for the triggering moment of a rectangular pulse shaper. It is shown, that any straightforward measures are not enough to reduce these errors. The rule of probability density distribution of the time when the forming device gets triggered, is stated not only as a whole, many widespread cases are shown as well. The resulting analytics can be used both to find a trade-off between parameters of a device operating in a noisy condition, and as a measure of the pure theoretical limit pulse-width modulation as well.

The existing Medley setup is being upgraded with Parallel Plate Avalanche Counters (PPACs) to measure neutron-induced fission cross sections. Single-gap PPACs have been developed for that purpose. The time resolution of the PPACs have been measured using a dedicated setup where, either α particles or fission fragments, are detected in coincidence by three PPACs and a Silicon detector. The results reported here demonstrate that the developed PPACs are suitable for the intended measurements in the white neutron beam at the NFS facility at GANIL.

The authors have developed a custom VLSI chip for the new generation of MCSD devices — multichip detectors with an extended analysis field and higher technical characteristics, which can be used in elemental analysis devices to simultaneously determine the elements that make up the material with high sensitivity and accuracy in real time. VLSI chip contains 384 channels with a spatial resolution of 25 microns has been integrated onto a single chip, each channel has a metal anode to collect the electrons as they emerge from the microchannel plate electron multiplier (MCP); a charge sensitive amplifier to produce a digital signal in response to the electron pulse and a 16-bit counter associated with it to accumulate the counts as they arrive and circuitry to read out the data sequentially from all channels in the microcircuit. The VLSI chip is designed according to the design rules standard 1,0 µm CMOS process. The speed of the microcircuit in the counting mode is at least 15 MHz, in the mode of reading information from the counters — more than 10 MHz. The output from the 16-bit counters on the detectors is presented via an 8-bit port and is read into the control electronics sequentially from each counter in turn in low-byte, high-byte order. The circuit has been designed in such a way that an arbitrary number of detector chips may be abutted together on a substrate behind the MCP, allowing for long focal plane detectors to be built, limited only by the size of MCPs available.

The design features and assembly technology of microelectronic coordinate-sensitive detectors of charged particles for spectroscopy are considered. The device is based on the specialized very-large-scale integration (VLSI) crystal manufactured using CMOS technology and containing a charge-sensitive matrix designed to detect isotope ions in a wide mass spectrum of the test substance. The range of concentrations measured by devices is also wide and ranges from 10–7 to 100%. The VLSI crystal is placed on a multilayer ceramic basis. The devices also contain a Hamamatsu micro-channel plate (MCP), electrodes that supply high voltage to integrated circuits (2.0 kV), a non-magnetic metal shield for protecting the device components, a connector and other structural elements. VLSI crystals are installed using the method of laying the microcircuits on a flexible aluminum — polyimide media. Such mounting method has a number of advantages over others. The VLSI crystals with project standards of 1 µm are designed for the possibility to create new generation of detectors, which can include either one or several crystals. The prototype version has been developed and it allows placing a bar of five ceramic-based crystals with a minimum gap of 100 µm between them. This design provides high reliability of products due to the usage of multilayer ceramic boards and due to progressive assembly methods used in the manufacturing of special-purpose microelectronic equipment, including the equipment resistant to special external factors.

Pulse-width modulation (PWM) signals used in various areas are sent to the receiver through a communications channel that distorts their waveform due to the limitations of the frequency range. It is not always possible to reduce additive (fluctuation) noises that are also present within the PWM signal to negligible levels. Limiting the range of frequencies transmitted over a communications channel results in both the deterioration of PWM signal front slopes and the changes in the spectral specifications of the fluctuation noise. The simulation of pulse signal formation helped identify a correlation between the pulse front slope and the number of harmonic components transmitted over the communications channel. Through the analysis, we established a correlation between pulse time and the additive noise parameters along with the bandwidth of the real communications channel. These calculations might be useful for problems where it is necessary to formulate the requirements for the communications channel transmitting the PWM signal.

The use of planting material with a root-balled tree system is one of the promising directions for creating artificial plantations. It is associated with radical changes in the cultivation of planting material and significant changes in the forest crops production technology [1]. The technology of widespread, woody plants year-round cultivation in the artificial environment can be implemented by using small-sized forms of cultivation structures - irradiation chambers and cabinet units, grow boxes, phytotrons, etc. In this case, the main technological operation is the light regime necessary for plants: with the radiation spectrum necessary for their development and growth, with the required intensity and irradiation regime. The results of photobiological studies on the qualitative indicators of woody plants grown in phytotron conditions under irradiation by radiation with different proportions in the blue-red and blue-green-red ranges of the photosynthetically active radiation zones are presented. The photosynthetically active radiation spectral variants, providing the highest or extremely close to it productivity of the indicated crops, were established. The complex and ambiguous nature of the photosynthetically active radiation main spectral ranges influence on the photoenergy and photoregulatory processes in plants, which ensure their productivity, is indicated, which makes it impossible to determine the general unified requirements for the artificial irradiation optimal parameters for growing plants.

In the complex trematode life cycle, cercariae transmit infection from the first to the second intermediate host. These short-lived lecithotrophic larvae possess a complex of behavioural responses for finding and infecting the host. We studied strategies used by cercariae of Himasthla elongata and Cercaria parvicaudata ( Renicola sp.) infecting mussels Mytilus edulis at the White Sea intertidal. Laboratory and field experiments were conducted in parallel. Geotactic response of cercariae was tested in an experimental chamber. Their distribution in nature was studied by counting larvae infecting mussels in cages installed in pairs (a ground and a suspended cage) in an intertidal lagoon. In the chamber H . elongata cercariae concentrated at the bottom, C . parvicaudata cercariae aged 1 h mostly concentrated near the surface and those aged 6 h sank to the bottom. A few larvae of both species (“evaders”) showed behavioural patterns antithetic to the prevalent ones. Infection was the highest in mussels in ground cages. In suspended cages mussel infection with H . elongata cercariae was much lower than with C . parvicaudata cercariae. Our study confirmed that results of experiments on cercarial behaviour could be extrapolated to natural conditions. Cercariae of two species using the same intermediate hosts and co-occurring in a biotope implemented dramatically different strategies. This might be associated with differences in cercarial output by parthenitae groups. The presence of “evaders” might be useful for successful transmission. Our results indicate that mussels cultivated in suspended cultures are at the least risk of infection with trematode larvae.

The effect of serotonin solutions on the locomotor activity of cercariae with different swimming patterns, Cryptocotyle lingua and Himasthla elongate, was investigated during their lifespan using motion track analysis and a frame-by-frame count of behavioral elements. Serotonin caused a noticeable alteration of several locomotion parameters in both species studied, while the activity per se decreased significantly with age. In intermittently swimming C. lingua cercariae, serotonin induced an increase in the frequency of active swimming phases (spurts) without significant changes in the duration and velocity of the spurts themselves. In continuously swimming H. elongata cercariae, serotonin increased the number of stops during the first hour after the emission from the host mollusk under a constant average swimming velocity. Immunocytochemical visualization of serotonin revealed a decline in its level with age (time after emission) and different dynamics of this process in neurons located in the tail and body of C. lingua cercariae. The data are interpreted in the light of the modulatory role of serotonin known for other animals.

The article considers the intelligent system of control and technical diagnostics of complex technological equipment and flexible production systems developed by the authors. The provision of automatic selection of important parameters from the entire set of input and output parameters is due to the additional training of the neural network in the process and perhaps by increasing-decreasing the number of active neurons that do not lead to deterioration in the quality of technical diagnostics, but also due to the choice of excess neurons and their activation by retraining or failure of the neurons of the network. Diagnostic systems may include sensors, a computer system, and diagnostic signal display devices. The computational part of the system can contain modules implemented with the possibility of intelligent analysis and containing a dynamic model that is implemented on a trained neural network, and a module implemented with the possibility of additional training of the neural network and the selection of active and redundant neurons.

Trematodes are common parasites in intertidal ecosystems. Cercariae, their dispersive larvae, ensure transmission of infection from the first intermediate molluscan host to the second intermediate (invertebrates and fishes) or the final (fishes, marine birds and mammals) host. Trematode transmission in polar seas, while interesting in many respects, is poorly studied. This study aimed to elucidate the patterns of cercarial emergence from intertidal snails at the White Sea and Barents Sea. The study, involving cercariae of 12 species, has provided the most extensive material obtained so far in high latitude seas (66–69° N). The experiments were conducted in situ . Multichannel singular spectral analysis (MSSA) used for processing primary data made it possible to estimate the relative contribution of different oscillations into the analysed time series and to separate the daily component from the other oscillatory components and the noise. Cercarial emergence had pronounced daily rhythms, which did not depend on the daily tidal schedule but were regulated by thermo- and photoperiod. Daily emergence maximums coincided with periods favourable for infecting the second intermediate hosts. Cercarial daily emergence rhythms differed in species using the same molluscan hosts which can be explained by cercarial host searching behaviour. Daily cercarial output (DCO) correlated negatively with larval volume and positively with that of the molluscan host except in cercariae using ambuscade behaviour. In the Barents Sea cercariae emerged from their molluscan hosts at lower temperatures than in the warmer White Sea but the daily emergence period was prolonged. Thus, DCO of related species were similar in these two seas and comparable with DCO values reported for boreal seas. Local temperature adaptations in cercarial emergence suggests that in case of Arctic climate warming trematode transmission in coastal ecosystems is likely to be intensified not because of the increased summer temperature but because of the prolongation of the warm season favouring cercarial emergence (transmission window).