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Literature data on the contents of secondary metabolite complexes in plants of the genus Teucrium L. (germander) including essential oil, phenolic compounds (flavonoids, iridoids), diterpenoids, and hydroxycinnamic acids are summarized. The spectrum of biological activity of these compounds is described both under normal conditions and in various pathological states. The need to determine the main quality indicators and develop methods for standardization of plant raw materials indicates further in-depth research of Teucrium species that can be sources of pharmaceutical substances for obtaining new drugs with antibacterial, antimicrobial, and radioprotective properties is promising.

Objective: to evaluate medical effectiveness of innovative forms of healthy lifestyle development for students of VSMU on the basis of a comprehensive study of the health status and lifestyle of students during the implementation of a health-saving project based on the example of the work of the «AcademicHealthCenter». Materials and methods: to solve these tasks, a complex of medical-sociological (questionnaires), clinical-statistical, biochemical and instrumental research methods was used. The objects of the study were: health indicators, conditions of the educational process, the quality and lifestyle of students of VSMU named after BurdenkoN.N. 537 students took part in the survey. Results: conceptual model on formation of infrastructural, organizational and administrative reserves for improving the quality of preventive medical work in the youth environment was developed and tested using the example of the creation of the «Academic Health Center». Conclusions: the developed model allowed not only to change the technology of rendering medical aid to students, but also to save funds in conditions of a funding gap, improve quality and accessibility of medical services to a socially unprotected category of the population.

The relative stability of diamond and graphite is readdressed from the new perspective of deductive molecular mechanics. Unlike most theoretical studies that are conducted numerically, this article uses an analytical model to gain insight into the fundamental reasons behind the quasi-degeneracy of these allotropes with very different bonding patterns. The relative energies of the allotropes are derived and several general statements about the structure of these materials are proven. This analysis yields a quasi-degenerate electronic ground state for graphite and diamond at 0 K. Numerical estimates based on this analysis are in astonishingly good agreement with experimental data and recent results of numeric modeling, despite the fact that they were obtained with a drastically smaller numerical effort. An extension of the proposed interpretation to silicon allotropes proves to be very successful as well. The proposed approach is also expanded to four-coordinated carbon allotropes, and the software package Adamas is developed, which is able to calculate allotrope energies and elastic properties (elastic moduli). In the case of diamond and graphene, some general statements could be proven from deductive molecular mechanics parameters. Specifically, it is shown that among the four-coordinated allotropes the cubic diamond structure represents the true minimum. In the cases of allotropes with some C—C bonds that are stronger than those in diamond, the energy gain is compensated by the mandatory presence of weaker bonds in the same allotrope, which leads to the overall increase of the energy relative to the diamond.

We propose an approach to construct monotonic finite difference schemes for solving the simplest elliptic and parabolic equations with the first derivatives and a small parameter at the highest derivative. For this, the notion of adaptive artificial viscosity is introduced. The adaptive artificial viscosity is used to construct monotonic difference schemes with the flow approximation of order $$O({{h}^{4}})$$ for the boundary layer problem and $$O({{\tau }^{2}} + {{h}^{2}})$$ for Burgers’ equation, where $$h$$ and $$\tau $$ are mesh steps in space and time, respectively. The Samarskii–Golant approximation (or upwind difference schemes) is used outside the region of high gradients. The importance of using schemes of second-order accuracy in time is outlined. The computational results are presented.

The anodic oxidation rate of silicon-on-insulator films fabricated by hydrogen transfer is studied as a function of the temperature of subsequent annealing. It is established that the oxidation rate of transferred silicon-on-insulator films is five times lower compared to the oxidation rate of bulk single-crystal silicon samples. The oxidation rate increases, as the annealing temperature is elevated in the range 700–1100°C and as the depth of gradually removed anode-oxidized layers is increased. The results obtained in the study are attributed to an increase in the efficiencies of the anodic current and oxygen–silicon interatomic interaction due to the annealing of defects and due to release of hydrogen from the bound state, respectively. The formation of hydrogen bubbles in the surface region of silicon due to the diffusion of hydrogen, released in the process of the oxidation reaction, towards micropores in the silicon-on-insulator layer is detected.

Об'єктом дослідження є температурне поле суцільного, нескінченого циліндра, який у розігрітому стані переміщено в охолоджуюче середовище. Математична модель цієї задачі складається з одновимірного квазілінійного диференціального рівняння теплопровідності, початкових і граничних умов. Безрозмірний варіант цієї математичної задачі розв’язано сітковим методом. Програмна реалізація алгоритму перевірена на реальному прикладі. Результати очікувані.

The measuring complex of the submillimeter range, implemented on the basis of a gas laser, is described. The technique of measuring the characteristics of dielectrics and the results are presented. It is concluded that it is possible to use the proposed method for validating the results of determining the dielectric characteristics of materials.

The possibility of using the emissions of shortwave (HF) broadcasting stations to detect airborne objects using the Doppler method is considered. It is shown that detection is possible at Doppler frequencies are spaced from the carrier frequency up to 60 Hz. In the decameter wavelength range, such objects are possessed by airborne objects moving at speeds up to 2000 kmph. The relation is given and the detection range of airborne objects is estimated, the requirements for the degree of suppression of the direct backlight signal are determined. The spectral characteristics of the signals of broadcast HF stations are experimentally investigated. Theoretical estimates of the RCS of airborne objects of various types at different polarizations, including aircrafts are made using the Stealth technology, are given. The noise levels in the Doppler detection frequency band are determined and the detection ranges of airborne objects are estimated. It is shown that when the backlight signal is suppressed at 30 … 40 dB, they can reach 200 km

The possibility of using the signals of global satellite navigation systems for diagnosing the state of the sea surface and monitoring waves is considered. The behavior of navigation signals during various sea conditions is analyzed. The possibility of monitoring the disturbance by the magnitude of the fluctuation and the level of fading of the trend component of the received GNSS signal is shown.

In this paper, we present the results of an experimental study of the statistical characteristics of interference of HF broadcast stations (spectra, distribution laws, at different frequencies and at different times of the day) and the results of their approximation by fractal and poly-Gaussian dependences

Recent advances in DNA sequencing open prospects to make whole-genome analysis rapid and reliable, which is promising for various applications including personalized medicine. However, existing techniques for {\it de novo} genome assembly, which is used for the analysis of genomic rearrangements, chromosome phasing, and reconstructing genomes without a reference, require solving tasks of high computational complexity. Here we demonstrate a method for solving genome assembly tasks with the use of quantum and quantum-inspired optimization techniques. Within this method, we present experimental results on genome assembly using quantum annealers both for simulated data and the $\phi$X 174 bacteriophage. Our results pave a way for an increase in the efficiency of solving bioinformatics problems with the use of quantum computing and, in particular, quantum annealing. We expect that the new generation of quantum annealing devices would outperform existing techniques for {\it de novo} genome assembly. To the best of our knowledge, this is the first experimental study of de novo genome assembly problems both for real and synthetic data on quantum annealing devices and quantum-inspired techniques., Comment: 9 pages, 4 figures

The authors consider the problems concerning the interaction of the digital economy and higher education in accordance with the Strategy of Information Society Development in the Russian Federation until 2030, which requires improving the learning process, developing new pedagogical technologies and methods that are oriented to modern conditions. The analysis of digital economy levels and their impact on the development of higher education is presented. The difference between modern university education and the previous model is revealed, expressed in the possibility of receiving it throughout life. The main feature of the technological base of production and higher education in the era of the digital economy is given. Universities are assigned the role of centers of innovation territorial clusters that provide a link between higher education institutions and production. Opposite trends of combining software and hardware systems into a single system and diversification of higher education are noted. The criteria for assessing the interaction between business and higher education in the digital economy are listed. The features of educational results (products) created in modern universities are briefly characterized. The development of massive open online courses and the division of universities of various sizes by the creation and use of software products are called the main factors that positively affect cost savings for university education. As conclusions, the authors represent the criteria for assessing the interaction of the digital economy and university education, including economic and institutional indicators, as well as the methodology for their processing.

Possibilities of using existing ground (TV centers, broadcasting stations) and space (global navigation satellite systems) radio systems for solving the problem of remote sensing and monitoring of the environment and objects in it are considered. The methods of diagnostics of the troposphere, description of the refractive index with the use of semi-Markov processes and atomic functions of Kravchenko-Rvacheva are proposed. The seasonal and altitudinal dependencies of radio-meteorological parameters and radio-climatic features of Ukraine were studied. Technologies for determining the effective gradient of the refractive index by damping factor of the VHF signals of television centers on the OTH routes in the zone of the near geometric shadow, on the angles of radioa "rise" and "sets" of the AES, detection of precipitation zones by the fluctuations of the pseudoranges and changes of the coordinates estimates, parameters of the surface of the earth by the fluctuations of the GNSS signals. Reviewers: Head of the Department of Radio waves propagation in the natural environments of the O. Ya. Usikov Institute for Radiophysics and Electronics NASU, Doctor of Physical and Mathematical Sciences, Professor Kivva F.V., Professor of the Department of Designing Radioelectronic Devices of Aircraft of the National Aerospace University. M.E. Zhukovsky (KhAI), Doctor of Technical Sciences, Professor Volosyuk V.K.

Within the framework of the kinetic approach, an analytical solution to the problem of diffusion of the light component of a binary mixture in a flat channel with infinite parallel walls is constructed. It is assumed that the mass of light component molecules and their concentration is much less than the mass of molecules and the concentration of heavy components. The flow rate of the heavy component is assumed to be zero. The change in the state of a light gas component is described on the basis of the BGK (Bhatnagar, Gross, Kruk) model of the Boltzmann kinetic equation. The diffuse reflection model is used as a boundary condition on the channel walls. The mass velocity profile of the light gas component is constructed. The flow rate of the light gas component per unit channel width is calculated. A comparison with similar results presented in open sources was done.

The possibility of using Latin squares for constructing two-dimensional non-equidistant antenna arrays that can be used for development of radio telescopes and systems for remote sensing of atmospheric and lithospheric radiation has been shown. An algorithm for calculating the coordinates of elements of a non-equidistant antenna array using the values of elements of Latin squares is proposed. It is shown that in this case, it is possible to obtain an almost complete coverage of the grid of spatial frequencies in the region of the arrangement of the elements at small filling coefficients of array. Directional patterns are studied and the side lobes levels are estimated for non-equidistant antennas obtained on the basis of Latin squares. The possibility of synthesizing of large antenna arrays on the basis of composite squares using the embedding of generative Latin squares is shown. The characteristics of the obtained arrays are studied. It is shown that using the shifts and mutual rotations of individual layers is involved in the synthesized array; its characteristics can be substantially improved.

The results of synchronous detection of the emission of various components of the electromagnetic and acoustic fields obtained under conditions of low industrial interference and a high level of microseismicity are investigated. To compensate electromagnetic radiation of lithospheric origin, a compensation method was used. The signal loop antenna, recording a mixture of signals of lithospheric and atmospheric-thunderstorm origins, was used as a magnetic core of a steel casing of the borehole. The compensating signal was recorded using an antenna, the receiving coil of which was identical to the coil of the signal antenna. The measurements were carried out in the seismically active region of Russia (the Kamchatka peninsula, the Paratun hydrothermal deposit) at the intersection of the sublatitudinal and submeridional fault zones. Methods for analyzing registration data of non-stationary processes are considered using the example of acoustic-electromagnetic emission of the lithosphere, the electromagnetic component of which is a component of the natural electromagnetic field of the Earth. Their characteristics are estimated and a statistical model is proposed that uses nested semi-Markov processes and finite atomic functions. Observations of geophysical electromagnetic fields, in addition to useful information about the emission processes, contain interference, mainly of technogenic origin. They are especially strong in downhole measurements when a well casing is used as the receiving antenna. These interferences significantly impede the allocation of useful information. The possibility of using bleaching filters to increase the contrast of observation of useful signals of lithospheric origin against their background is considered.

A numerical method for solving two-dimensional problems of a viscous compressible gas based on Navier–Stokes equations with the introduction of adaptive artificial viscosity is presented. The proposed method is implemented for areas of the general form on triangular grids. The method of the adaptive artificial viscosity is taken as the basis of the proposed numerical method and ensures the monotonicity of the solutions, even in the presence of shock waves. The artificial viscosity (introduced into the difference scheme) is constructed in such a way that it is absent in the boundary layer where the dynamic viscosity acts. The viscosity is determined from the conditions of the fulfillment of the maximum principle. The series of calculations of an external flow around a cylinder for various Reynolds and Mach numbers is described.

Seven male volunteers aged 22–27 years took part in the laboratory experiment for the determination of body response to acute normobaric hypoxia where they inhaled an oxygen–nitrogen gas mixture (9% of О2) for 25 min. At least 100 cardiac cycles at each of six experimental time points have been recorded by using an electrocardiogram (ECG) recording technique in standard lead II. Mean heart rate (±SD) before hypoxia was 64 ± 2 bpm; the duration of the PP interval was 0.94 ± 0.07 s, that of the PT interval was 0.51 ± 0.02 s, and that of the TP segment was 0.41 ± 0.07 s. Five minutes after hypoxia, it has been found that heart rate (HR) increased by 19%; the duration of the PP and PT intervals and TP segment decreased by 16%, 6%, and 30%, respectively. Twenty minutes after hypoxia, all the parameters reached their initial values. Five and fifteen minutes after hypoxia, HR reached 59 ± 3 bpm; PP interval and TP segment increased by 9% and 14%, respectively, compared to the initial values; PT interval was the same as the initial value at the baseline. The correlation coefficient rp (PP/PT) was 0.10–0.54; rp (PP/TP) was 0.94–0.99. The intervals PP and TP were found to be identical.

The study analyzed the experience of using ultrasound and X-ray methods of research to identify the pathology of the mammary glands in women of different age groups. A comparative analysis of the diagnostic significance of the two radiological methods of research was carried out, which made it possible to propose a new algorithm of screening the pathology of the mammary glands in the course of additional clinical examination taking into account age-specific features. It is noted that the X-ray method of research in some cases is not sufficiently informative, which is associated with individual characteristics of the ratio of tissues constituting the mammary glands, and the potential risk of non-recognition of malignant tumors against the background of X-ray dense glandular tissue. Ultrasound examination method has several advantages that can compensate for the disadvantages of the X-ray method. However, the use of ultrasound in the clinical examination is not fixed by law. We strongly believe that the inclusion of an ultrasound method of examination in the algorithm of screening breast pathology with additional clinical examination will optimize the diagnostic process and ensure the timely start of treatment with appropriate pharmaceutical preparations. Key Words: breast cancer, screening

The spreading of solid Cu nanoparticles (1–10 nm in diameter) on the (100) Cu surface and solid Au nanoparticles on the (100) Au face is simulated via molecular dynamics. The results for the Cu (nanoparticle)/( 100) Cu system are compared with the available experimental data for Cu microparticles (0.1–10 μm) spreading on the polycrystalline Cu surface. The solid-state spreading phenomenon is found to play an important role in many natural and technological processes. Some potential applications in nanotechnology and restrictions in the operation characteristics of nanosized units and nanomaterials are discussed as well.

We present explicit three-layer difference schemes for the transport equation with the use of adaptive artificial viscosity. These schemes have the third-order approximation with respect to time and the first-order approximation with respect to space for the unstable case of forward differences. We compare these schemes with their known analogs on a series of standard tests in various norms.

A model of an automated system of pretilt angle measurement and azimuthal anchoring energy in LC cells is developed. The automated system with ability to external control of measurement parameters. A software for the system control, data collection, transformation and analysis of measurement data is developed to comparison of the experimental and theoretical results.

An automated system for measuring the diffraction efficiency of light, as well its kinematic scheme, were designed and assembled. The measurements of the diffraction efficiency of light on the sample of polymeric substrates with periodic microrelief were carried out. The software is developed in Matlab environment for the construction of the diffraction pattern of the geometric parameters and wavelength. By using software as well as the results of measurement of the light diffraction efficiency the microrelief period was determined too. The correctness of the period was checked by an independent method

A numerical technique based on the method of adaptive artificial viscosity is proposed for solving the viscous compressible Navier–Stokes equations in two dimensions. The Navier–Stokes equations is approximated on unstructured meshes, namely, on triangular or tetrahedral elements. The monotonicity of the difference scheme according to the Friedrichs criterion is achieved by adding terms with adaptive artificial viscosity to the scheme. The adaptive artificial viscosity is determined by satisfying the maximum principle conditions. An external flow around a cylinder at various Reynolds numbers is computed as a numerical experiment.

We consider the possibility of using illumination of the HF broadcast stations for location of air objects. The relationships for estimation of the detection range are obtained and requirements for the degree of suppression of a direct signal from the broadcast station are determined. Spectral characteristics of the signals from HF broadcast stations are studied experimentally for different polarizations of the received radiation. The possibility of air object detection using the Doppler effect is shown. Theoretical estimates of the radar cross section of air objects for different polarizations of the incident radiation are given. It is found experimentally that the radar cross section is about the same for the vertical and horizontal polarizations.

Two supersonic axisymmetric flows, in which the incidence of a shock wave on the axis of symmetry leads to the formation of return (circulatory) flow zones, are numerically modeled. The former of these flows is of the wake type with a ram pressure deficit in the vicinity of the axis of symmetry. The numerical results obtained are in qualitative and quantitative agreement with the available experimental data. The latter flow is generated by a hypersonic spherically-symmetric source placed on the axis of a cylindrical channel. An analysis of the obtained solutions, together with their comparison with the data in the literature, suggests that the formation of the above-mentioned circulatory flow zones is physical, rather than computational, in nature. There is also reason to believe that the phenomenon under consideration is hydrodynamic, rather than dissipative, in nature.

The paper is devoted to experimental investigation of the spatial distribution of electromagnetic field in the vicinity of the tapered wire medium formed by copper wires conductors in the millimeter waveband. The experimental technique, based on the small perturbations method and used the special software has been elaborated for electromagnetic field distribution registering. The optimal type of probe has been determined. The electromagnetic energy concentration in the vicinity of the narrow planes of the tapered wire medium has been demonstrated experimentally. It is shown that the width of the wave beam behind the narrow facet of the lens insignificantly increases with distance. The field patterns with resolution ± 0.01dB in the vicinity of wide planes of lens have been registered.