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Aim: To verify reference values of the heart rate variability (HRV) parameters among healthy 18-27-year olds in the Khanty-Mansi autonomous okrug - Ugra, Eastern Siberia. Methods: Data were collected in series of observational analytical cross-sectional studies between 2006 and 2020. The sample consisted of 13269 subjects - 7442 women and 5827 men aged 18 to 27 years permanently living in Khanty-Mansi autonomous okrug. We studied parameters of background HRV on short-term recordings in the time and frequency domains, Poincare graph and cardiointervalography by R. M. Baevsky. For all HRV parameterswe assessed minimal and maximal values as well as the 3rd, 10th, 25th, 50th, 75th, 90th and 97th percentile. Gender differences in all studied variables were studied using Mann-Whitney tests after normality testing using Kolmogorov-Smirnov tests with Lilliefors correction. Results: We observed significant differences between central tendencies of all studied HRV parameters between women and men (p < 0.01) with the exception of the relative power of the spectrum in the very low frequency range - an indicator of the adequacy of the regulation processes and the vegetative rhythm indicator. Conclusions: The reference values of the HRV parameters for young adults living in the Khanty-Mansi Autonomous Okrug-Ugrawere verified. Significant gender differences in all the studied HRV parameters were observed except one, which is considered to be an indicator of the adequacy of the regulation processes and the vegetative rhythm indicator. We also discuss applying centile values of the relative spectral power of HRV to identify categories of heart rate modulation.

A mesoscopic dielectric cuboid antenna (DCA), which can be connected to a standard waveguide, is proposed to achieve high directivity with a simple-structure and low-profile antenna compared with that of a horn antenna of same dimensions. We optimized the antenna dimensions based on simulation to maximize the antenna gain of 14.22 dBi, which is 1.9 dB higher than that of the horn antenna with the same dimensions. Simulation was performed both at 300 and 24 GHz. As a proof of concept, we designed and fabricated a scaled DCA with dimensions of 1.2 $\lambda \,\times \,1.2\lambda \,\times \,1.36\lambda$ and experimentally evaluated the radiation pattern at 24 GHz band. The full-width at half-maximum (FWHM) values were approximately 21% and 34% narrower than those of the horn antenna in the E -plane and H -plane, respectively. The frequency characteristic of sensitivity enhancement using the DCA as the reception antenna shows that the DCA is a nonresonant antenna with a wide bandwidth. Narrower FWHMs of the DCA have been discussed with respect to a two-dimensional near-field phase distribution measured using the electrooptic sensing technique.

The recombinant OmpF porin of Yersinia pseudotuberculosis as a model of transmembrane protein of the β-barrel structural family was used to study low growth temperature effect on the structure of the produced inclusion bodies (IBs). This porin showed a very low expression level in E. coli at a growth temperature below optimal 37 °C. The introduction of a N-terminal hexahistidine tag into the mature porin molecule significantly increased the biosynthesis of the protein at low cultivation temperatures. The recombinant His-tagged porin (rOmpF-His) was expressed in E. coli at 30 and 18 °C as inclusion bodies (IB-30 and IB-18). The properties and structural organization of IBs, as well as the structure of rOmpF-His solubilized from the IBs with urea and SDS, were studied using turbidimetry, electron microscopy, dynamic light scattering, optical spectroscopy, and amyloid-specific dyes. IB-18, in comparison with IB-30, has a higher solubility in denaturants, suggesting a difference between IBs in the conformation of the associated polypeptide chains. The spectroscopic analysis revealed that rOmpF-His IBs have a high content of secondary structure with a tertiary-structure elements, including a native-like conformation, the proportion of which in IB-18 is higher than in IB-30. Solubilization of the porin from IBs is accompanied by a modification of its secondary structure. The studied IBs also contain amyloid-like structures. The results obtained in this study expand our knowledge of the structural organization of IBs formed by proteins of different structural classes and also have a contribution into the new approaches development of producing functionally active recombinant membrane proteins.

PURPOSE This report proposes an approach to develop a method of microwave imaging for early, non-invasive diagnosis of breast tumors. Here we describe a data-processing method for obtaining radio images of biological heterogeneities and a new method for filtering static noise in received signals. METHODS A specialized radar system was developed in the present study and used to perform sounding of synthetic phantoms with the dielectric properties of breast tissue in the range of 2-8 GHz. Datasets thus contained synthetic structures that imitated the dielectric properties of breast tissues and tumors. The permittivity values of the created artificial materials were verified using a waveguide cell. Tumors were simulated via plastic balls with a diameter of 1 cm that were filled with saline. A special ultra-wide band (UWB) radar system developed at Tomsk State University was used to register radar responses from the phantoms. The radar system included the vector reflectometer, the UWB antenna, and the mechanical scanner that provided sounding in the hemisphere. We also used the time-domain signals processing method to obtain the radio image signals. In this method, all signals received during scanning in the hemisphere are added with calculated delay for the given focus point. Special filtering of the constant components of the signal at each of the angular sounding latitudes was used to eliminate clutter in the received signal. This solution allowed us to account for additive clutter in the received signal from structural elements during scanning in the hemisphere. The influence of the number of angles on the quality of the resulting radio image was evaluated. RESULTS The phantoms of a female breast and a malignant tumor from artificial materials with electrophysical characteristics close to those of real tissues have been developed. This facilitated verification of the proposed method for constructing radio images under more clinically relevant conditions. The proposed filtering of the constant components of the signal effectively doubled the signal-to-noise ratio in the resulting radio image compared with the standard algorithm of clutter filtering. The influence of different numbers of scan points on the quality of the final radio image are presented herein. It is concluded that it is sufficient to use not more than 600-800 sounding points for acceptable image quality. A further increase in the number of angles does not significantly improve image quality despite increasing the scan time. CONCLUSIONS Scanning in the hemisphere of the breast phantom using the proposed method of clutter filtering show that multi-angle microwave imaging can form accurate three-dimensional (3D) images with double the level of signal-to-clutter compared with the standard filtering approach. The images of artificial tumors were obtained when sounding in the range of 2-8 GHz with the resolution of about 5-7 mm.

It is proposed to use the tomographic approach to the problem of detecting and imaging concealed utility networks. This approach is based on generating the three-dimensional radio images of the space being explored from the results of measuring its location wave projections in a dual-polarization measurement mode. The problem is solved by focusing radiation first on the “air–dielectric” interface and then inside the dielectric. Experimental data processing results and reconstructed threedimensional radio tomograms are provided for a “twisted pair” cable and a fiber-optic cable with no metallic inclusions. The results confirm the operability of the approach.

The paper shows the method for detecting and mapping inhomogeneities in biological tissues with using the radio-wave tomosynthesis. The method of radio-wave tomosynthesis allows calculating a three-dimensional distribution of permittivity in a studying space. The distribution gives the opportunity to determine tissue inhomogeneities, also their location and size. This method is suitable for dynamic observation of changes in education size due to harmlessness to humans. Unlike X-ray methods, for which regular doses of ionizing radiation contraindicated. Therefore, the development of non-invasive methods for the search for inhomogeneities in biological media based on radio-wave sounding is very relevant.

Article contains results of the analysis of the existing ways and technological solutions of joint warehousing of waste of coal preparation factories: watery (slurry), jellied slurry and firm (gravitational) in the way of formation of external dumps. The reasons of the knitting properties of watery waste of coal preparation and possibility of their interaction with a surface of the waste stored in rock dumps are established. These properties of joint types of waste allows coal preparation factories to provide work without operation of external slurry settlers for a turn of the clarified technical water. Using properties of an optimum ratio of participation of different types of waste at mutually dense formation circles of storages when forming dumps becomes possible to solve a problem of stability of slopes in time. Change of activity puzzolanovy is considered at change of chemical and mineralogical structure of rock. It is established that the general for rock of coal preparation factories is availability of active alumina in the form of radicals of the dehydrated clay minerals or in the form of active alumina, silicon dioxide and ferruterous connections, are characterized by high sorption ability. These conclusions are confirmed by justification of indicators: basicity modules, aluminous, silicate and coefficient of quality.

The concept of dielectric spherical or cylindrical particle in resonant mode as a cloak system is offered. In fundamental modes (modes with the smallest volume correspond to |m| = l, and s = 1) the field is concentrated mostly in the equatorial plane and at the surface of the sphere. Thus under resonance modes, such perturbation due to cuboid particle inserted in the spherical or cylindrical particle has almost no effect on the field forming resonance regardless of the value of internal particle material (defect) as long as this material does not cover the region where resonance takes place.

In this paper, a method for detecting and mapping inhomogeneities in biological tissues using the radio-wave tomosynthesis method is presented. The proposed method of radio-wave tomosynthesis allows us to calculate the three-dimensional distribution of the permittivity of the space under study and, thereby, to detect tissue inhomogeneities and to determine their location and size. Due to their harmlessness for humans, these methods are suitable for dynamic observation of changes in the size of formation, in contrast to x-ray methods, for which regular doses of ionizing radiation are contraindicated. Therefore, the development of non-invasive methods for the search for inhomogeneities in biological media based on radio-wave sounding, which makes it possible to identify pathological formations, is now very relevant.

It's considered the principle possibility of creation the managed reflectors for formulation of given field distribution in the focus area. Reflectors change the reflect ratio in dependence of the external control. The proposed theoretical modeling of such controlled focused device which provides focuse to a specific point in a given distribution of the reflectors. On the basis of numerical simulation it's considered the application of this approach for the solution of the problem of radiotomography.

The authors propose a solution of the problem of radiovision using the reflective array, each element of which can change the reflection coefficient under the action of external control voltage. The focusing abilities of flat reflection array of monochromatic radiation were studied to solve the problem of radiovision. The array element based on waveguide with a controlled reflection coefficient was developed. The phase shift switching is 180°.

This paper presents a novel sharpness metric for color images. The proposed metric can be used for no-reference assessment of image visual quality. The metric basically relies on local power of wavelet transform high-frequency coefficients. It also takes into account possibility of presence of macrophotography and portrait photography effects in an image where the image part (usually central one) in sharp whilst the remained part (background) is smeared. Such effects usually increase subjective evaluation of image visual quality by humans. The effects are taken into consideration by joint analysis of wavelet coefficients with largest and smallest squared absolute values. Besides, we propose a simple mechanism for blocking artifact accounting (if an image is compressed by JPEG) and compensation of this factor contribution. Finally, the proposed sharpness metric is calculated in color space YCbCr as a weighted sum of sharpness components. Weight optimization has shown that a weight for intensity component Y is to be considerably smaller than weights for color components Cb and Cr. Optimization of weights for all stages of sharpness metric calculation is carried out for specialized database NRTID that contains 500 test images with previously determined MOS (Mean Opinion Score). Spearman rank order correlation coefficient (SROCC) determined for the designed sharpness metric and MOS is used as optimization criterion. After optimization, it reaches 0.71. This is larger than for other known available no-reference metrics considered at verification stage.

A task of no-reference visual quality metric verification is considered. A test set that contains 500 JPEG format images having different distortions is created. The results of experiments carried out by 316 volunteer observers to evaluate visual quality of images are presented. The experiments allowed obtaining mean opinion scores (MOS) based on averaging the evaluations. Several non-reference image visual quality metrics have been analyzed. Spearman and Kendall correlations between MOS and metrics values are calculated. It is shown that all analyzed metrics have not enough correspondence to human perception.

Gas analyzers employ a variety of physical-chemical processes including photocalorimetry, electrochemistry, thermal catalysis and others. Most of the analyzers are designed with certain drawbacks like insufficient serviceability of electrochemical or catalytic thermal sensor and, consequently, the requirement of periodic replacement and calibration, the necessity of periodic resupply of expendables (photocalorimetric) etc. utilization of these systems in pressurized modules is complicated because of the necessity of regular resupply and coordination of experiment duration with gas-analyzer maintenance operations. The problem can be resolved by introduction of semi-conductor gas sensors functioning on the principle of reactivity of metal-oxide conduction to a measuring substance. A zinc oxide semi-conductor sensor was tested for ozone with calculation of the dependence of wanted signal on substance concentration. The tests were performed in steady and pulsed mode of sensor operation.

We report about light-emitting diodes (LEDs) and photodiodes (PDs) for the spectral ranges 1.8 - 2.4 micrometer and 2.9 - 4.7 micrometer based on multicomponent III-V alloys (GaInAsSb/GaAlAsSb, InAsSb/InAsSbP). High-efficiency small-dimension optoelectronic devices were applied to the design of novel set gas and moisture analyzers. Progress in development of different kinds of experimental models of the analyzers is demonstrated. Such portable sensors can be used for ecological monitoring, detecting industrial pollutants, and for various medical applications.© (1995) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

Genetically hypertensive and normotensive rats were subjected to acute myocardial injury by a single subcutaneous injection of adrenaline (0.5 mg/100 g bw). The animals were sacrificed one day later. The lesions showed the signs of focal coagulative necrosis and intracellular myocytolysis. The damaged cardiomyocytes with high sarcolemmal permeability for blood plasma proteins were more widespread in the hypertensive versus normotensive rats. Intracellular myocytolysis, which is not associated with alterations in the cell membrane, was found in both experimental groups at an equal rate. The data agree with the concepts of alterations in biological membranes in genetically determined arterial hypertension.