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The article is devoted to the formation of a spray cloud after the interaction of an ultrajet with an obstacle. Variants of different mutual arrangement of the ultrajet and the surface on which the impact occurs are considered. Evaluation of the effectiveness of the choice of angle is carried out by analyzing the values of the coverage area of the target with a spray, set at a fixed distance from the impact site. It is accepted that a large contact area of the spray with the target surface is the best possible result. The research was carried out within the framework of the RFBR grants 18-29-18081 and 19-38-90228\19, the grant of the President of the Russian Federation for state support of the leading scientific schools of the Russian Federation NSh-3778.2018.8 and grants from the Innovation Promotion Foundation under the UMNIK-18 program in accordance with contract No. 14727GU/2019 and No. 14549GU/2019.

Studying the issues of recovery of low-potential energy at smallscale energy facilities allowed to show the promising character of the organic Rankine cycle (ORC) technology as a technology for recovery or conversion of low-potential energy.The most promising developments in the field of the use and recovery of waste heat are described regarding application of ORC, which is widely used in geothermal sources, hot water boilers, gas turbine plants. Due to the constantly growing diversity of working fluids, ORC can be used within a wide temperature range from 100°C to over 350°C. Also, developments are underway in the design of ORC generators to increase reliability of its individual system units, such as turbines and expanders. Based on the above factors, it can be concluded that with a deeper study of the problems of adopting ORC technologies, they can become a very promising direction in development of heat power engineering.It has been determined that the main factor hindering the widespread adoption of the ORC technology is associated with high cost of heat exchange equipment due to increased heat exchange surfaces. It is shown that design of mini power plants and energy centres based on the use of low-potential energy requires improvement of mathematical modelling methods to reliably determine operating modes and characteristics of each of the units. Methods for modelling evaporation and condensation systems, including turbines and expanders using organic low-boiling working fluids, should be considered among the methods that are highly sought after. The methods for selecting a working fluid for ORC devices also have a significant impact on characteristics of the installation determining the range of cycle operating temperatures and pressures. The solution of the above problems can lead to a reduction in the cost of heat exchange equipment, and, consequently, to a decrease in costs for design of ORC generators.

Background. Trabecular bone score obtained by lumbar spine Dual-energy X-ray Absorptiometry is a novel and insufficiently explored instrument of accessing trabecular bone quality. One of its promising applications is early diagnostics of osteoporosis (OP) before fragility fractures appear. Meanwhile most of systemic inflammatory rheumatic diseases affect bone tissue either directly and indirectly by glucocorticoids consumption. Both factors potentiate OP development and can influence the trabecular bone score. Aims — to evaluate the possibilities of trabecular bone score using in rheumatology. Materials and Methods. Data analysis of domestic and foreign scientific publications. Results and Discussion. Authors of analyzed publications note stable association of low trabecular bone score with vertebral fractures, its correlation with local inflammatory markers in lumbar spine and ankylosing spondylitis structural progression. In most studies trabecular bone score do not have association with systemic inflammatory activity and treatment. Conclusion. Trabecular bone score is effective in OP diagnostics in rheumatic patients, evaluation of local inflammatory activity in the lumbar spine and structural progression of ankylosing spondylitis.

The effect of the velocity of compact metal projectiles of spherical and cylindrical shapes on the size of craters formed in steel targets of different strength was studied in the velocity range 2–10 km/s by numerical simulation using two different computational techniques. The behavior of the materials of the projectile and target is described using a model of a compressible elastoplastic medium with a constant yield strength. The projectile materials are copper, titanium, and tantalum. The projectile mass and velocity are specified assuming that their kinetic energy is constant. It is found that the dependences of the crater depth on the velocity of projectiles with constant kinetic energy have a maximum and the crater volume decreases monotonically with increasing velocity.

Aim. To conduct a comparative analysis of the microbiome of biopsies of a tumor and normal intestinal epithelium of patients diagnosed with colorectal cancer and to identify of functional activities of the obtained bacterial isolates that affect the development of the tumor. Methods. The study included 50 patients with malignant neoplasms of the colon: 36 men and 24 women. The mean age of the patients was 64.110.2 years. To analyze the microbiota of the biopsies, DNA samples were obtained from the tissue of the unaffected colon mucosa and tumor of the patients. Bacterial 16S rRNA genes fragments were amplified using bar-coded primer bakt_341f. Metagenomic next-generation sequencing was performed using the MiSeq platform (Illumina, USA). The obtained data were processed by bioinformatic methods using the QIIME package. Recognition of microorganisms depending on the morphotype and gram staining of the microflora was carried out using combination differential media and biochemical tests. Statistical analysis was carried out using Microsoft Excel, Service Pack 2 for Office XP, Statistica 6.0 (StatSoft). A comparative analysis was performed with the Student's t-test and the MannWhitney test in case of unmet conditions of validity. Alpha diversity of bacterial communities was quantified by the Shannon diversity index and the UniFrac distance for beta diversity analysis. Results. In patients with colorectal cancer, 5 bacterial phyla were isolated, the predominant of which were Firmicutes and Bacteroidetes, while the content of Actinobacteria was low. In addition, a higher number of representatives of Fusobacteria was observed in the tumor tissue compared to the tissue of a healthy mucosa, at a distance of 5 centimeters proximal to the tumor. The results of this study indicate that the microbiome of a tumor and a healthy mucosa fundamentally differ from each other not only in morphotype and gram staining but also in antagonistic, hemolytic and ribonucleolytic activities. Conclusion. Colonization of the tumor by dominant aggressive Gram-negative bacteria leads to significant changes in the tumor microbiome composition compared with normal mucosa, whose representatives are displaced from the damaged epithelium by more aggressive strains.

An analysis of the errors of the measuring optical power divider of laser radiation, which is used to transmit a unit of average power of high-intensity laser radiation and is structurally made in the form of a wedge, is carried out. The error of the division ratio, which affects the accuracy of the unit transmission, is determined. The estimation of the random component of the division coefficient error is carried out and it is shown that the proposed method for its determination, based on the rearrangement of the used measuring instruments, gives the most probable estimate. The error caused by the nonlinearity of the measuring instruments that determine the division coefficient is investigated, and its largest interval is estimated. It is shown that in the case of invariability of the conversion coefficients of the used measuring instruments on the laser radiation power, the method makes it possible to exclude the dependence of the error in determining the division coefficient on the mentioned coefficients, and in another case, to reduce their influence on the transmission error. The possibility of controlling the division factor of the divider by determining the control parameter and its confidence interval when transmitting a unit of radiation power is substantiated; a formula for calculating this interval in each measurement cycle is obtained. It is shown that the value of the parameter and the change in the confidence interval can be used to control the reliability of the transmission of the unit of power to the calibrated measuring instrument in real time.

The procedures of the technical support of zootechnical and veterinary measures for beef cattle breeding were considered in the article.

A method is proposed for transferring the unit of mean power of laser radiation by means of measuring high-intensity power (kilowatts), with the possibility of constant monitoring of the transfer process. A measuring optical power divider for laser radiation has been developed, structurally built in the form of a wedge and permitting, according to the relatively small power of the radiation reflected from the lighted surface of the forward face of the wedge, to determine the radiant power of the beam incident upon the measuring instrument to be calibrated. The proposed method is based on applying the developed divisor in the reference installation and provides for the implementation of three modes of operation of the installation: the mode for determination of the coefficient of equivalence; the mode for determination of the division ratio of the optical splitter; the mode of transfer of the power unit by measurement facilities; and determination of the control parameter of the optical splitter. The transfer process is monitored by measuring the radiant power reflected from the back edge of the wedge, and determining the control parameter. The conditions in which it is advisable to use the proposed mode of determining the division ratio of the optical splitter are given. A special feature of the method under study is the possibility of timely monitoring of the division ratio of the optical splitter, making it possible to estimate in real time the reliability of the process of calibration of measurement instruments. A formula was derived for the metrological traceability of the power measurement results to GET 28-2016. The basic error component errors of the determination of the radiant power arriving at input of the measurement facilities being calibrated are considered. The results of the experimental studies of this method make it possible to confirm that at 10.6 μm wavelength, the total measurement error of the power, expressed as the SD, does not exceed 2.0%. The method can be used in the corresponding secondary standards of the power unit that obtain a unit from the State Special Standard for Mean Power, GET 28-2016.

A single-phase physico-mathematical model of a high-speed waterjet forming process that uses the underwater abrasive waterjet cutting technology while an abrasive-liquid flow under a pressure ranging from 60 to 80 MPa passes through the jet-forming path of a mobile abrasive waterjet machine has been developed. The results of a numerical experiment are presented. It has been shown that the main structural parameters of the internal profile of the jet-forming element (the profile of the focusing cavity, diameter and length of the output-channel) influence the geometric and kinematic parameters of the formed jet and the consumption of the hydro-abrasive suspension.

In ankylosing spondylitis, the pathological metabolism of the bone tissue is regulated by various proteins; of these, Dkk-1 protein, an antagonist of the Wnt-signaling pathway, is of particular interest. We compared the methods of Dkk-1 detection in the blood serum of patients with ankylosing spondylitis (conventional ELISA and aptamer/antibody assay) and analyzed the relationship between Dkk-1 level and structural progression of ankylosing spondylitis and secondary osteoporosis. Dkk-1 levels in patients were significantly increased and depended on the stage of the disease, but not on the presence/absence of osteoporosis. Thus, Dkk-1 is a potential serum marker of progression of ankylosing spondylitis reflecting a tendency to structural progression of the disease before the appearance of radiographic changes. The results obtained by both methods practically coincided, which suggests good prospects for applying DNA aptamer-based test system.

For testing anti-meteoroidal protection of spacecraft, it is proposed to use charges that form compact elemants of variable shape. Shape charges, their construction, and the process of functioning are considered. During the operation of such a charge, the explosive throws the metal liner at a distance of several hundred charge diameters. The metal liner is deformed in motion and takes a compact shape. In this case, copper liner of variable thickness were used, the outer and inner surfaces of which are formed by a combination of spherical surfaces. A plane-wave generator with a variable angle of inclination of the detonation wave is considered as an initiation system in the charge. The results of mathematical modeling of the functioning of charges, which determines the effect of charge parameters on the effectiveness of the action, are presented. The efficiency of the charges was determined by the parameters of the compact element - its shape and speed. The paper also evaluated the influence of the angle of inclination of the plane-wave generator on the shape of the element. The dependences of the speed of the element and its elongation on the angle of inclination of the converging detonation wave are obtained. It was found that when the angle of inclination of the converging detonation wave front decreases, the elongation and speed of the compact element increase.

The results of mathematical modeling of the process of forming elongated element from segment charge liners for testing anti-meteoroid protection of spacecraft using numerical methods of continuum mechanics are considered. The paper presents options for improving such charges to increase their effectiveness. Data from computational experiments with various structural parameters of steel segment liners are described. In models with different physical and mechanical properties of the facings, the mechanism of forming an elongated element from the liners with a gradient in the radial direction of plasticity is demonstrated. It is shown that the control of physical and mechanical properties in the liners makes it possible to form filled and aerodynamically stable element. The application of the elastic-plastic deformation model and the fracture criterion in the form of the Smirnov-Alyaev criterion is justified.

The paper introduces the results of numerical simulation of the functioning of shaped charges, whose liners are made of different materials. As a result of their functioning, these charges form high-speed elements. Typically, liners for such charges are produced by the cold stamping technology. An alternative method for producing the liners is metal spinning. Moreover, a spin formed liner is expected to have higher physical and mechanical properties compared to a stamped liner made of the same material and having the same geometrical parameters. To reveal the patterns of molding high-speed elements from stamped and spin formed liners, the action of shaped charges comprised of steel or copper segmental liners of small bending, was simulated numerically using the apparatus of continuum mechanics. The influence of the liner manufacture method was taken into account by varying the values of the physical and mechanical characteristics of the liner material. The design parameters of the simulated charge, with the exception of the liner bending, during the calculation study remained unchanged and corresponded to the parameters of the currently used samples. Following the numerical experiments results, the study shows that the elements molded from spin formed liners are less likely to become fractured while being formed and are also more integral (continuous) in comparison to the elements molded from stamped shaped charge liners.

Ankylosing spondylitis (AS) is a chronic progressive systemic inflammatory disease, with a primary lesion of the spine and sacroiliac joints characterized by simultaneously running processes of osteogenesis (syndesmophytes) and osteoresorption (osteoporosis). The aim of this work is to investigate trabecular bone score (TBS) correlation with signs of AS structural progression and markers of AS activity in the males before 50. Twenty one AS male patients before 50 without osteoporosis are included in investigation. The relationships between TBS, the Kellgren sacroiliitis stage, and BMD indices in different parts of the skeleton were studied using Spearman correlation analysis. A negative correlation was found between TBS and the X-ray stage of Kellgren sacroiliitis (r = -0.49; p

The paper considers the possibility of using compact projectiles formed by an explosion to break through strong steel barriers of finite thickness protected by a layer of water. There is no problem in penetrating such barriers by high-gradient and high-speed shaped-charge jet of a small diameter formed by shaped charges with ‘high’ conical liners, however, the diameter of the through hole formed in the steel barrier is fairly small and does not meet the defeat criteria for corresponding barriers. To increase the diameter of a through hole in a steel barrier, shaped charges with ‘low’ conical or flat hemispherical liners (in the form of a meniscus) forming compact projectiles can be used, but the movement of such ‘shock cores’ in the water layer is sharply slowed down, up to a complete stop even before interacting with the main steel barrier. The purpose of the paper is to substantiate the possibilities of eliminating this disadvantage when using compact projectiles. Based on theoretical and experimental studies, the paper offers a technical solution related to the known fact of the formation of a cavern (gas cavity) during the movement of a shaped-charge jet in water, expanding as the jet penetrates in the radial direction. In this case, if a known tandem scheme of shaped charges placed one after the other along the axis of the explosive device is used, the first shaped charge, often called pre-charge, will penetrate the body in the head part of the explosive device to the water layer, then form in the latter a cavern up to the main penetrable barrier and the second shaped charge, often referred to as the primary, will form a compact projectile moving to penetrable barrier in the cavity formed by the penetration of shaped-precharge jet in the water. At the same time, due to selecting the necessary delay time between the pre-charge and main charge explosions as well as the design parameters of the pre-charge, the size of the expanding cavity must exceed the size of the compact projectile, excluding its interaction with water up to the approach to the penetrable steel barrier.

In this paper, we present the results of numerical simulation of explosive formation of a high-speed compact element from copper, steel, and aluminum cumulative liners combining the shape of a hemispherical segment smoothly converting into a cylindrical surface (“hemisphere–cylinder” liners). The problem is solved in a two-dimensional axisymmetric setting considering the limiting parameters of the dynamic stress-strain state causing plastic flow and destruction of the cumulative liner material. The original model of the functioning of cumulative shaped charge, which determines the effect of individual elements of the cumulative liners, including the difference in numerical characteristics of their physicomechanical properties and critical destruction conditions, on the final parameters of the high-speed compact element, was used. The plastic properties of the material and the critical conditions for its destruction were found not to affect the final velocity of the formed high-speed compact element, but they affect its shape, dimensions, and mass.

We substantiate the recommendations for improving the efficiency of hydro- and hydroabrasive cutting of the honeycomb structures that are widely used in aircraft and rockets, obtained by numerical solving of the spatial dynamic problem with allowance for the physico-mechanical and kinematic parameters of a high-speed jet, the physico-mechanical and structural parameters of the treated honeycomb structure, and the parameters of the technological treatment (feeding and the impact angle of the jet with the face surface of the blanks). A physico-mathematical model and a method of numerical analysis of the process have been developed. The influence of the above parameters on the quality of the surfaces of the treated blanks is illustrated. The results of the calculations are compared with the experimental data.

Herpes simplex virus type 1 is a highly contagious worldwide prevalent infection, which, once it enters the organism, persists during its whole lifetime. According to World Health Organization estimates, about 3.7 billion people under the age of 50 years (90% of the human population) are infected with by HSV-1 worldwide. The important role played by ribonucleases (RNases) in protection of the cell and whole organism from viruses has been confirmed by a considerable body of data that allow considering RNases not only as immune system components, but also as a basis for development of the new antiviral drugs. The purpose of the present work was to demonstrate the antiviral activity of the RNase from Bacillus pumilus (binase) toward HSV-1 at the cell entrance and reproduction stages. Virus treatment with binase in the concentration of 100 μg/mL for 60 min reduced virus replication in the bovine kidney epithelial cell culture MDBK by 100 times compared with untreated virus. Development of cytopathic effects produced by untreated virus in the cells grown on the medium with binase was retarded by 7 h compared with the growth of virus-infected cells on the medium without binase. It may be suggested that HSV-1 treatment with RNases reduces its ability to enter the cell; antiviral action of RNases toward the intracellular virus is realized at the initial stage of virus reproduction.

Results of nanoscale study (by atomic force microscopy and X−ray diffraction) of single−, two− and three−layered Cr, Cu, Al and Ni metallic nanofilms formed on a ceramic sital substrate on MVU TM−Magna T magnetron equipment (NIITM, Zelenograd) have been reported. The growth rates and the structure of the nanofilms were determined while varying of power/current ratio from 200/0.7 to 800/2 Wt/A and magnetron sputtering time from 30 to 360s at an operating pressure of 0.5 Pa Ar. The criterion for optimization quality based on the minimum roughness was as follows: Ra = min{Rai} and/or Rq → min{Rqi} (i is the number of varies modes used). The mean roughness Ra and RRMS = Rq have been determined from the scan of the vertical profile (resolution 20 pm) of the atomic force microscopic image. We found that the nanofilm–forming nanocluster structure size for the modes when Ra and Rq were the smallest had a close–to–Gaussian grain size distribution. The film growth rates have been determined based on the atomic force images of the nanofilm structure in the form of either a single step or steps obtained at different time intervals. The mode and parameters of magnetron sputtering and the composition of the Cr, Cu, Al and Ni targets affect the size of clusters which form the surface of the metallic nanofilms. X−ray phase and structural analyses have been carried out in order to determine the texture and the change in the distances between the lattice planes. The correctness of the optimization criterion correlating the nanolayer deposition parameters and their quality has been corroborated by the coincidence of the magnetron sputtering modes which provided for the lowest roughness and the smallest average size of the X−ray coherence region as using the Debye− Scherrer equation.

The expediency of improving the indicators of judgment assessments of individual breeding characteristics of the Hereford cattle breed is justified. The proposed method of selecting cows according to a complex evaluation indicator is based on the principle of a point assessment with the correction of the selection significance of the absolute value of some economically useful characteristics that are definitely related to the economy of animal breeding. At the same time, it is characterized by the Breeding Value Index (BVI), which allows you to complete a selection group of cows in breeding herd with breeding value from 70 points and above. The main values of constructed index must select or create such genotypes that would combine the most important and desirable combinations of breeding traits. The method is universal for cows of different breeds, types, herds, provides breeding and formation of more highly productive and technological animals on the basis of meat productivity.

Members of the genus Bacillus can successfully counteract a sudden increase in salinity. In addition to the accumulation of osmolytes, saline stress also affects other aspects of bacterial physiology such as exoenzymes synthesis and motility. Here, we have shown that increase of salinity in growth medium leads to elevated biosynthesis level of low-molecular weight ribonuclease (RNase) binase I from Bacillus pumilus. The same effect was established previously for high-molecular weight binase II. Transmission electron microscopy revealed the absence of flagella and some other changes in salt-stressed cells of B. pumilis. We also detected the gene sequences homologous to the recognition sites of response regulator DegU in the binase I and binase II promoters. Using the B. subtilis strains with various mutations in DegU gene, we found that the two-component signal transduction system DegS-DegU which regulates the motility under salt stress participates in the control of biosynthesis for both secreted RNase of B. pumilis (binase I and binase II).

Bacillus are soil saprophytes, facultative anaerobes developing in the temperature range of 28–37°С. 16S rRNA cataloging shows that these bacteria form a coherent class with broad variability of virulence. Bacillus phages can be extensively used for phagotyping bacteria in the process of soil, water, and food monitoring. Bacillus phages can also be used as vectors in horizontal gene transfer and potential therapeutic agents. Thus, description of the biological diversity of the Bacillus phages is useful for further development of tools used in molecular biology and biomedicine. In this work, the scheme for isolation of soil bacteriophages was unified, which allowed ten bacillus phages to be isolated from different types of soil. It was shown that the number of phages depended on the soil fertility, decreasing as the soil changed from black soil to chestnut soil to gray forest soil to uncontaminated urban soil to oil-contaminated urban soil. A new polyvalent DNA-containing bacteriophage SRT01hs of B. altitudinis (it is also able to infect B. subtilis, B. cereus, and B. pumilus, but not B. licheniformis and B. atrophaeus) was described in detail. It has a typical structure: a total length of 360 nm and an icosahedron-shaped head 100 nm in diameter. Several phages simultaneously attack a B. altitudinis cell by increasing the level of intracellular low-molecular RNA. Infection with the phage virtually eliminates the stationary growth phase of infected bacilli and leads to a permanent increase in the number of phages in cultural liquor, with the exception of the time period of high activity of the secreted ribonuclease.

The study proposes to use charges forming high-speed elongated elements (HSEE) with a variable shape for ground-based simulation of the penetration of particles and elements into the spacecraft's hull. During the operation of such a charge, an explosive throws a metal lining over a distance of several hundred charge diameters. The metal segment lining is deformed during the throwing process and takes the form of an elongated element. In calculations we used steel linings with a degressive and progressive profile whose outer and inner surfaces are formed by spherical surfaces, as well as by a combination of spherical and conical surfaces. The paper shows the results of a numerical analysis which determines the effect of the geometric and physico-mechanical parameters of segmented cumulative linings on the efficiency of the charges forming high-speed elongated elements. The efficiency of the charges was determined by the characteristics of the formed element, i.e. elongation, degree of fullness and the diameter of the horizontal stabilizer. Furthermore, we established the dependences which describe the effect of the lining material dynamic yield point and the radius of transition of the spherical surface to the conical surface on the elongation of the element and the diameter of the horizontal stabilizer. We also showed the possible contradictory effect of changing the radius of transition of the spherical surface of the lining into the conical surface on the aerodynamic stability parameters of the high-speed elongated element.

The article discusses the features of mathematical modeling of technologies using high-speed water jet (for cutting, piercing, cleaning, including their use in the underwater conditions), as well as features of material destruction under water jet treatment. The physical-mathematical model of the process based on the use of the proposed equations of hydroabrasive suspension state and criteria-based dependencies describing the regularities of the processed material destruction was developed on the example of numerical solving two-dimensional axisymmetric problem of piercing holes in the structures of various materials by hydroabrasive waterjet. The features of the solid material destruction during the formation of a through hole in it under the action of a high-speed water jet are shown. Recommendations on choosing kinematic parameters of the cutting jet for different types of waterjet/hydrodynamic machining are given.

The experimental study identified the antiviral activity of Bacillus pumilus RNase (binase) against the reovirus of serotype 1/strain Lang. For the first time, it has been found that 50 μg/mL of binase effectively reduced the hemagglutinin and cytocidal activity of reovirus in Vero cell line. The preincubation of the enzyme with reovirus before infection of the cells inhibited the viral replication. To determine the stagedependent effect of reovirus reproduction upon binase inhibition, the infected cells were treated with binase or RNase A at different phases of the infectious cycle. The treatment of virus-infected cells has revealed that both enzymes have a maximal antiviral effect on the reovirus propagation during early phases of the reovirus reproduction cycle, with binase being more effective than RNase A. It has been hypothesized that the combined action of the oncolytic reovirus and binase is promising for the elimination of tumor cells carrying mutated RAS gene.

We consider the physicomathematical formulation of the problem of explosive formation of a penetrator from a low-sphericity copper lining. Calculations are made for the formation of a penetrator for a phlegmatized hexogen charge for two models of the behavior of the lining material (copper), and the results are compared with the experimental data.

For ground-based simulation of the penetration of particles and elements into the body of the spacecraft, it is proposed to use charges that form high-speed elongated aircraft (HSEA) with a variable form. In the course of the operation of such a charge, an explosive agent throws a metal liner for a distance of several hundred charge diameters. The metal segment liner is deformed in the process of throwing and takes the shape of an elongated aircraft. Steel cladding with a degressive and progressive profile was used, the outer and inner surfaces of which are formed by spherical surfaces, as well as a combination of spherical and conical surfaces. The results of the numerical analysis, which determines the influence of the geometrical and physicomechanical parameters of segment cumulative liners (CL), on the effectiveness of the action of the charges that form high-speed elongated aircrafts are presented. The effectiveness of the charges was determined by the characteristics of the formed aircraft — elongation, degree of fullness, and diameter of the tail plane (skirt). Dependencies describing the influence of the of the liner material and the radius of transition of a spherical surface into a conical surface on the elongation of the aircraft and the diameter of the skirt are established. The possible contradictory effect of a transition in the radius of transition of a spherical liners surface into a conical surface on the parameters of the aerodynamic stability of a high-speed elongated aircraft is shown.For ground-based simulation of the penetration of particles and elements into the body of the spacecraft, it is proposed to use charges that form high-speed elongated aircraft (HSEA) with a variable form. In the course of the operation of such a charge, an explosive agent throws a metal liner for a distance of several hundred charge diameters. The metal segment liner is deformed in the process of throwing and takes the shape of an elongated aircraft. Steel cladding with a degressive and progressive profile was used, the outer and inner surfaces of which are formed by spherical surfaces, as well as a combination of spherical and conical surfaces. The results of the numerical analysis, which determines the influence of the geometrical and physicomechanical parameters of segment cumulative liners (CL), on the effectiveness of the action of the charges that form high-speed elongated aircrafts are presented. The effectiveness of the charges was determined by the characteristics of the formed aircraft — elongat...

This paper deals with specifics of mathematical modelling of machining processes using high-speed hydro-abrasive water jet (for cutting, piercing, cleaning) including the case of underwater application. We provide a numerical solution of the two-dimensional axis-symmetrical problem of hole piercing in structures from various materials and propose a mathematical model of this process. The mathematical model is based on the proposed equations of hydro-abrasive suspension state equations and criteria relationships describing the laws of material erosion for the given machined material.

The facultative aerobic bacteria isolated from the mucosa of rectum in the zone of malignant tumor and neighboring normal mucosa in patients with colorectal cancer were studied using molecular genetic methods. The species attribution of bacteria was implemented using the cultural morphological analysis and sequencing of the 16S rRNA locus. The microorganisms with intraepithelial invasion to rectal mucosa were identified as the representatives of adherent-invasive (AIEC) subgroup of Escherichia coli and species Klebsiella pneumonia. The molecular analysis by genetic determinants controlling adhesive, hemolytic, and toxigenic activity revealed that some bacterial isolates were able to produce toxins with potential cancerogenic activity (e.g., colibactin and cytotoxic necrotizing factor 1). Certain bacterial species isolated from malignant and normal rectal epithelium of the same patient demonstrated no difference between analyzed factors of toxigenicity.