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The technology of two-cut rough and rough turning of rotation bodies in relation to lathes is considered. Dynamics of part working surfaces formation by longitudinal oscillations of cutters with phase delay of finishing cutter from rough one is shown. Dynamics of finishing cutter in function of damping coefficient is considered. The mathematical model of two-cut turning process is given.

The problem of modeling the process of functioning of redundant measuring instruments is considered. The determination of the frequency of verification of complex duplicate measuring instruments is validated on the basis of a semi-Markov model of the process of functioning of the instruments. The importance of the use of the theory of semi-Markov processes for modeling the functioning of redundant technical systems, including measurement systems, is demonstrated. A semi-Markov model of the process of functioning of measuring instruments by means of which the influence of such factors as the frequency of verification, support of measuring instruments with spare parts, level of failure-free performance, and degree of maintainability on the reliability of measuring instruments may be taken into account is developed. A method of specifying a semi-Markov process that correctly and adequately approximates the true process is found. The availability factor of the measuring instruments is selected as the indicator of the operating efficiency of the functioning of a measuring instruments and of the corresponding model.

The morphometric parameters and surgical areas of risk of retroperitoneal approach were studied for endoprosthetics of intervertebral discs in the lumbar spine to reduce trauma and reduce the risk of complications. The study included 110 patients operated on in the period from 2017 to 2020 (72 men, 38 women) in the neurosurgical department of the 1586 Military Clinical Hospital. The average age of the patients was 44.9 ± 15.4 years. According to the localization of access to the lumbar spine, the patients were distributed as follows: L III –L IV — 8 (7.3%), L IV –LV — 46 (41.7%), L V –S I — 56 (51%). It was found that, for the intervertebral disc L V – S I , the length of the skin incision was 92.5 (80; 100) mm, the length of the surgical wound was 80 (80; 110) mm, the thickness of the subcutaneous fat layer was 30 (15; 40) mm, the depth of the wound was to the spine — 85 (70; 120) mm, the depth of the wound to the spinal canal — 125 (107.5; 152.5) mm, the angle of operation in the horizontal plane at the level of the spine — 52 (47; 59.5) degrees. On the basis of the anthropometric data of patients, the optimal length of the skin incision was determined for performing the retroperitoneal approach (120 mm for level L III –L IV , 100 mm — for level L IV –L V ). Three variants of the inferior vena cava bifurcation have been identified for different levels of intervertebral discs in the lumbar spine: high bifurcation, left common iliac vein mainly overlaps the left half of the L IV –L V intervertebral disc and does not overlap the L V –S I intervertebral disc; middle bifurcation, left common iliac vein overlaps the central part of the intervertebral discs L IV –L V and L V –S I ; low bifurcation, inferior vena cava overlaps the right side of the intervertebral disc L IV –L V , inferior vena cava and left common iliac vein completely overlap the intervertebral disc L V –S I . The data obtained can be used when planning retroperitoneal access to the lumbar spine in order to reduce the trauma of the operation.

The problem of modeling the process of functioning of redundant measuring instruments is considered. On the basis of the developed model, the determination of the frequency of verification of complex duplicated measuring instruments based on the semi-Markov model of the process of their functioning is justified. The relevance of the application of the theory of semi-Markov processes for modeling the functioning of redundant technical systems, including measuring instruments, is shown. A semi-Markov model of the process of functioning of measuring instruments has been developed, which allows us to take into account the influence of the frequency of verification, the provision of measuring instruments with spare elements, as well as the level of reliability and maintainability on the reliability of measuring instruments. A method is found for defining a semi-Markov process that correctly and adequately approximates the real process. The indicator of the effectiveness of the functioning of the measuring instruments and the corresponding model is the availability factor of the measuring instruments.

Extracellular matrix plays a pivotal role in biofilm biology and proposed as a potential target for therapeutics development. As matrix is responsible for some extracellular functions and influence bacterial cytotoxicity against eukaryotic cells, it must have unique protein composition. P. aeruginosa is one of the most important pathogens with emerging antibiotic resistance, but only a few studies were devoted to matrix proteomes and there are no studies describing matrix proteome for any clinical isolates except reference strains PAO1 and ATCC27853. Here we report the first biofilm matrix proteome of P. aeruginosa isolated from bronchoalveolar lavage of patient in intensive care unit. We have identified the largest number of proteins in the matrix among all published studies devoted to P. aeruginosa biofilms. Comparison of matrix proteome with proteome from embedded cells let us to identify several enriched bioprocess groups. Bioprocess groups with the largest number of overrepresented in matrix proteins were oxidation-reduction processes, proteolysis, and transmembrane transport. The top three represented in matrix bioprocesses concerning the size of the GO annotated database were cell redox homeostasis, nucleoside metabolism, and fatty acid synthesis. Finally, we discuss the obtained data in a prism of antibiofilm therapeutics development.

Extracellular matrix plays a pivotal role in biofilm biology and proposed as a potential target for therapeutics development. As matrix is responsible for some extracellular functions and influence bacterial cytotoxicity against eukaryotic cells, it must have unique protein composition. P. aeruginosa is one of the most important pathogens with emerging antibiotic resistance, but only a few studies were devoted to matrix proteomes and there are no studies describing matrix proteome for any clinical isolates. Here we report the first biofilm matrix proteome of P. aeruginosa isolated from bronchoalveolar lavage of patient in intensive care unit. We have identified the largest number of proteins in the matrix among all published studies devoted to P. aeruginosa biofilms. Comparison of matrix proteome with proteome from embedded cells let us to identify several enriched bioprocess groups. Bioprocess groups with the largest number of overrepresented in matrix proteins were oxidation-reduction processes, proteolysis, and transmembrane transport. The top three represented in matrix bioprocesses concerning the size of the GO annotated database were cell redox homeostasis, nucleoside metabolism, and fatty acid synthesis. Finally, we discuss the obtained data in a prism of antibiofilm therapeutics development.

The results of the conservative and surgical treatment of 12 patients at the Neurosurgery Clinic of the Military medical academy. CM. Kirov, in the period 2016-2018, about the paraarticular and disc cysts of the lumbar spine. Performed open microsurgical and full-endoscopic operational aids. Evaluation of the effectiveness of surgical treatment was carried out using the subjective assessment scale and magnetic resonance imaging over time. The follow-up period ranged from 6 to 24 months. Most often, extradural cysts were located at the level of the LIV-LV segment. Clinical manifestations were characterized by radiculopathy and local back pain. The average duration of pain syndrome was 3±0,7 months. Conservative treatment led to a regression of pain and resorption of a disk cyst in one patient. In other cases, surgical treatment was required. The average duration of a microsurgical operation was 131,6±73,4 minutes, video endoscopic - 80±10,8 minutes. The hospitalization period in the group of microsurgical treatment was 10,4 days, in the group of video endoscopy - 4,7 days. Control magnetic resonance imaging revealed the recurrence of paraarticular cysts in the area of the previous operation in 3 patients. Relapse in patients with disc cysts is not marked. Necessity in repeated operations did not arise in one supervision. It has been established that the main clinical manifestations of extradural cysts of the lumbar spine are local moderate pain, radiculopathy, and intermittent claudication. Microsurgical and percutaneous video endoscopic treatment of lumboischialgia due to extradural cysts is significantly more effective compared with conservative therapy. Full-endoscopic interventions in comparison with microsurgical ones are less invasive and long-lasting and can reduce the time of inpatient treatment.

The article presents a case of surgical treatment of primary multiple benign tumors of the cauda equine of different histological origin: spinal nerve root schwannoma and ependymoma of the filum terminale.Представлено описание случая хирургического лечения первично-множественных доброкачественных опухолей конского хвоста спинного мозга с различным гистологическим строением: шванномы корешка спинномозгового нерва и эпендимомы конечной нити.

Background. The advantages of the spray-pyrolysis method are the ability to produce films with a high area and a high degree of uniformity at acceptable (from 100 to 500 °C) process temperatures. The method does not require the use of vacuum at all stages of the process. The aim of the study is to select the optimal technological parameters for obtaining transparent conductive coatings based on tin dioxide with minimal surface resistance. Materials and methods. Such technological stages of the process of obtaining samples of transparent conducting oxides based on tin dioxide are presented in the research as preparation of the surface of glass substrates; preparation of precursor solutions; deposition of pure and antimony-doped films of tin dioxide on the surface of substrates. Results. A method for the synthesis of transparent conducting oxides samples based on tin dioxide by the spray-pyrolysis method was developed, and the optimal values of technological parameters aimed at achieving the minimum surface resistance of samples with a SnO2 coating were established empirically. Conclusions. The proposed technological modes make it possible to synthesize by spray pyrolysis transparent conducting oxides based on tin dioxide with a surface resistance RS = 27 Ohm/□, which corresponds to the modern world level of industrially produced transparent conducting coatings based on tin-doped indium oxide. The results obtained confirm the feasibility of manufacturing transparent conductive coatings based on tin dioxide by spray-pyrolysis.

Results of experimental assessment of efficiency of use of low-temperature air plasma of the arc category of atmospheric pressure at treatment of burns of skin of the III degree in small laboratory animals are given. It is established that use of low-temperature air plasma of the arc-type discharge of atmospheric pressure allows to accelerate terms of final healing of wounds for 49% (p0,05), to reduce development frequency in them purulent inflammation by 45,5% (p0,01). Positive influence of air and plasma processing on dynamics of the area of a hem which after single influence by 35 days is reduced for 67% is revealed (p0,01). The analysis of a histologic picture confirms acceleration of formation of an extracellular matrix and epitelization against the background of impact of an air and plasma stream on wounds. Processing of a wound of low-temperature air plasma of the arc category of atmospheric pressure after an early surgical escharotomy allows to form on a wound surface a so-called nanofilm of a layer the coagulated proteins of wound exudate and cellular fragments which has selective vapor permeability, reduces an rate of wounds pathogenic infection, prevents drying and as a result, allows to reduce the frequency of development of purulent complications and extent of zones of a secondary necrosis. Influence of a stream of low-temperature air plasma of the arc-type discharge of atmospheric pressure allows to optimize significantly processes of reparative regeneration in a zone of a deep burn of skin at a stage of preparation for their surgical treatment.

The results of percutaneous endoscopic and microsurgical discectomy have been compared. It was established that the operative intervention time, bed-day medians and disability period were significantly shorter (p0,001) in the percutaneous endoscopy group. The average effective dose of radiation exposure for a patient during transforaminal endoscopy was 4,4 mSv, for interlaminar endoscopic techniques and microsurgery - 0,8 mSv. The proportions of complications and repeated operations in both groups were comparable. The risk of recurrence was 10% for the endoscopic group, 4,8% for the microsurgical group. Significant differences in terms of local and radicular pain, quality of life and the physical component of health have not been established. The mental component of health was the best in the endoscopic group. Good and excellent results on the MacNab treatment satisfaction scale in the endoscopy group were observed in 78,2% of cases, after microdiscectomy - in84,9%. Lower invasiveness of percutaneous endoscopy affected the reduction in the period of hospitalization and disability. The effectiveness of percutaneous endoscopic discectomy methods was comparable to standard microsurgical techniques. A statistically insignificant increase in the risk of hernia recurrence after percutaneous endoscopic discectomy was noted. Infectious complications were not typical for percutaneous endoscopic discectomy. Differences in the frequency of complications and reoperations between percutaneous endoscopic and microsurgical lumbar discectomy are also not confirmed.

The results of experimental evaluation of the effectiveness of topical application of the peptide human leukemia differentiation factor-6 in carbopol hydrogel easier to disperse 2020 in thermal burns of skin of III degree are presented. It was found that local application of human leukemia differentiation factor-6 peptide in hydrogel carbopol in concentration from 0,01% to 0,00001% causes acceleration of wound epithelialization processes by 28 days by 71,11% (p0,01) and reduces the incidence of purulent complications by 62,5% (p0,05). Histological examination of biopsy specimens of wounds revealed essential features of morphometry, considering the chosen method of treatment and concentration of peptide of human leukemic factor-6 differentiation in carbopol hydrogel. The proposed method of local treatment of burn skin lesions is very promising for optimizing the flow of reparative regeneration processes. The low frequency of purulent complications in the group of animals treated with a minimum peptide content may be due to the combined action of carbopol hydrogel as determinants of wound healing in a wet environment, and the optimal concentration of the peptide human leukemia differentiation factor-6, providing anti-inflammatory effect in a minimum concentration. Analysis of the histological pattern in the studied groups of animals allows us to conclude about the acceleration of the formation of the extracellular matrix, and epithelialization of the wound surface on the background of an application of the peptide human leukemia differentiation factor-6 minimum concentration. On the 14th day of observation the number of microvessels in granulation tissue among animals treated with human leukemia differentiation factor-6 in carbopol hydrogel easier to disperse 2020 with minimum concentration (0,00001%) was 40,6-43,75% more than in the comparison groups. The use of biologically active peptides is one of the promising methods of wound process optimization. human leukemia differentiation factor-6 peptide can selectively stimulate proliferation by enhancing redox processes in cells.

The study objectiveis to determine the feasibility and effectiveness evaluation of full-endoscopic surgery in gunshot wound of the lumbar spine.Materials and methods.A clinical case of a 24-year-old male who received a gunshot wound to the lumbar spine is described. The patient underwent a full-endoscopic intervention aimed at extracting a bullet from the spinal canal.Results.Minimal-invasive approach to spinal canal with the possibility to extract a bullet, decompression of nerve roots, defect closure of the dura mater is demonstrated.Conclusion.Good clinical outcome allows to recommend the full-endoscopic surgery with similar gunshot wounds of the lumbar spine at the stage of specialized care.

A review of the literature on the comparative evaluation of the effectiveness of various techniques of posterior cervical foraminotomy is presented. Fully endoscopic posterior foraminotomy is considered to be a good alternative to standard methods of cervical discectomy for lateral "soft" intervertebral disc herniation with monoradicular syndrome. Along with similar clinical efficacy, the procedure has the merits that are common for minimally invasive interventions. The study focuses on technical aspects of fully endoscopic posterior cervical foraminotomy. A detailed and illustrated description of the surgical technique is given. A clinical case demonstrates its performance and outcome.

The construction of objects of critical infrastructures such as a new roads, utility tunnels, communication networks, underground parks and other structures is associated by the way with generation of vibrations in the vicinity of the underground structures, and not only human lives can be lost but also extensive material damage can be expected due to technological and natural hazards based on vibrations. This paper presents the general governing equations for coupled thermo-hydromechanical process in the tunnel surrounds. Modeling and analysis of laminated composite cylinder applied for the objective analysis of shock wave propagation in the soils and possibilities to estimates of the tunnel structure damage.

Today we have to point that in Europe continually rising risks not only of the technical accidents but extra risks due to the high number of people coming back to Europe from Middle Asia battle field with a unique experiences and connections to international terrorist community. Still, that's of a great fortune, with the exception of several minor incidents, terrorists have not attacked nuclear facilities, stolen nuclear weapons or weapon-grade nuclear materials, nor even committed credible nuclear hoaxes. That means that we have to start thinking about protection of civil population in case of fallouts due to both terrorist and accidental hazards. However, due to modern legislative in Czech Republic it's only personal blast and fallout shelters. Especially for modern city population it could be problematic to find a solution depend on size, hardness and location. So now it's on a state government how to solve problem with the mass public fallout shelters, especially if it's not a new construction but retrofit of the underground shelters. Shelter construction program would rival that of a major state financial programes, so only way is to retrofit those in underground spaces that was decommissioned after the high water in 2002 Still, for today, it's political problem of allocating the resources to maintain the inventory of fallout shelters and identify space with some blast protection potential for protection of civil population. That means that we have to improve even our theory for verification of rock caverns stability for retrofit and conversion.

Broadband ultrasonic spectroscopy used to measure residual stresses in samples of high-temperature alloys. It is shown that the acoustoelasticity method and laser ultrasonic spectroscopy can be used to determine the depth distribution of residual stresses. Measurements were carried out on test samples of heat-resistant nickel-base and titanium-base alloys with specified distribution of residual stresses after vacuum heat treatment, vibratory stress relief or shot peening. The results were compared with the residual stresses determined from changes in the deformation upon the removal of layers from the sample by electrochemical etching.

A series of tests was conducted to investigate the blast resistances of the building to premixed methane-air interior burning and explosion. Explosion process of the gas methane medium (in the inner space) extremely depend on the object site configuration. An interior deflagration of premixed methane-air burning and explosion in a specific vented chamber can happens due the all hazards: natural, criminal, terrorist, and accidental. The full scale object was tested as control specimen. LVDTs and pressure transducers were used to record deflection histories, and pressure sensors measured airblast pressure histories. In the first stage of a study two experiments of methane-air system in differ proportion were carried out.

The parameters of a conical stabilizer and its effect on the aerodynamic characteristics of the high-speed air vehicle, in general, are examined. The flow characteristics of an high-speed air vehicle with a conical stabilizing device are analyzed. Simulation results are compared with experimental data. Qualitative features of the supersonic flow associated with the characteristics of the drag of an aerodynamic configuration with a stabilizing device in the form of a truncated cone are considered. Particular attention is paid to the physical aspects of the flow around the considered configurations and to elucidating the mechanisms responsible for a minimum in the drag coefficient of a wingless high-speed air vehicle. A general mechanism of occurrence of the minimum in the drag coefficient for aerodynamic configurations with a conical tail stabilizer is studied.

Tautomerism of benzaurins and hydration are studied. 1H and 19F chemical shifts have been determined for a number of substituted 4-hydroxyphenyl-diphenyl carbinols containing fluorine in a 3-, 3*- or 4*-position, and for similar compounds containing additional methyl groups in a position of 3, 3** or 4**. The same data have been obtained for the fuchsones prepared by dehydration of the above carbinols. On this basis chemical shifts of fluorine in different positions have been evaluated as a monitor of the transformation of 4-hydroxyphenyl group to the semiquinone moiety. The 19F NMR can be used to monitor the transformation of 4**-fluorobenzaurin and the related 3,3*-disubstituted and 3,3*,5,5*-tetramethylsubstituted compounds to the corresponding carbinols due to the addition of a water molecule and to study the tautomerism of the two latter benzaurins as well as that of 3,3*,4**trifluorobenzaurin. Furthermore, fluorine and methyl group chemical shifts are sensitive to syn-anti-isomerism in substituted fuchsones.The prototropic process of these compounds may be slow or fast on a 1H NMR time scale depending on the solvent and may be catalyzed by water or carbonic acids. On the basis of kinetic and thermodynamic data obtained by dynamic NMR studies, a mechanism for the process has been proposed.

The dynamics of dopamine and norepinephrine contents in the dorsal hippocampus of rats immunized with a dopamine-BSA conjugate was studied during immobilization stress by mean of the microdialysis technique. Immunization with dopamine conjugate was accompanied by intensive production of antibodies against dopamine in rat blood and a tendency toward an increase in dopamine content in the dorsal hippocampus even in the basal state (before stress exposure). Under stress conditions, dopamine content in the dorsal hippocampus of immunized rats significantly increased. In control rats, stress was accompanied by a significant increase in norepinephrine content in the dorsal hippocampus. The observed peculiarities in dopamine and norepinephrine contents in the dorsal hippocampus of rats immunized with a dopamine conjugate were typical of active animals more resistant to emotional stress.

This paper is a study mainly aimed to understanding of deflagration and explosion characteristics of methane gas system explosion in a tunnel structures. Underground infrastructure structures are threatened by aftermaths due the all hazards: natural, criminal, terrorist, and accidental such as a gas detonations, bumps, terrorist attacks, etc. Human victims, decreasing of bearing capacity of the structural system and long-lasting traffic troubles can be very extensive. This is why it is of great importance to assess dynamic impacts of explosives, which are required by some contractors or developers for lowering the danger of damage of structures. In order to fulfil these demands accurate computation is necessary and on the other hand also new protective structures and methods have to be suggested and verified. The expensive, time consuming or even dangerous experiments should be proved by the numerical methods. A series of tests was conducted to investigate the blast evaluation of premixed methane-air burning and explosion in the underground tunnel. LVDT and pressure transducers were used to record deflection histories and measured air blast pressure histories. The full-scale experimental study was performed by the Scientific-Research Coal Institute VVUU in Ostrava under the supervision of the Department of Technology of Building, Czech Technical University in Prague. The analysis of the tunnel structure caused by a blast load is presented in this paper based on the time-dependent measurements of the response of the underground structures to the blast wave loads that were successfully recorded using a variety of measurement devices.

Ab initio MP2 computations have been performed for the interaction of acetylene with HgCl2 in the gas phase with the formation of β-chlorovinyl-derivatives of mercury. It has been shown that the precursors of these compounds are the π-complexes of HgCl2 with one or two molecules of acetylene, which are formed without activation energy. It has been shown that all cis-isomers possess the higher stability than the trans-isomers. The calculations of the frequencies of normal vibrations and intensities in the IR spectra have been carried out. The activation energies of formation of β-chloroviniyl-derivatives of mercury in the gas phase have been calculated. It has been shown that the intermediates of π-complex type can be transformed only to the unsymmetric cis-isomer. The formation of the symmetric cis–cis-isomer is unlikely on the account of the high activation energy of the process. The suggestion has been made concerning the possibility of obtaining π-complexes of HgCl2 with one or two molecules of acetylene upon matrices isolation.

The experimental approaches to estimation of comparative electronegativity and chemical hardness of organometallic groups have been proposed. Qualitative data on the electronegativity of L n M groups were obtained from F NMR study of model systems 4-FC 6 H 4 QML n (Q = C≡C, N(R), O, C(O)O, S), (4-FC 6 H 4 ) 3 SnML n and (4-FC 6 H 4 ) 3 SnQML n (Q = O, S), containing a great variety of different organometallic groups containing transition or heavy main-group metals. The data on chemical hardness of L n M groups were obtained from NMR study of distribution of different L n M groups between hard and soft anions. The following basic results have been obtained. (1) The relative electronegativity and chemical hardness of L n M groups can change in parallel or not with the electronegativity and hardness of the central metal atom. (2) The substituents in Ar can substantially modify electronegativity and hardness of Ar n M groups; the influence of Ar groups has an inductive nature; the increase in electron-donating ability of aryl ligands enhances the hardness of Ar n M cations. (3) The relative electronegativity and hardness of L n M groups in L n MX are invariant and do not depend on X.

The Ni(II) triazenide complex, trans -( o -Tol)Ni(PEt 3 ) 2 N 3 Ar 2 (Ar= p -FC 6 H 4 ) ( 1 ), was synthesized by the reaction of trans -( o -Tol)Ni(PEt 3 ) 2 Br with Ar 2 N 3 Na. The crystal structure as well as the 1 H-, 19 F- and 31 P-NMR spectra in toluene- d 8 at different temperatures are reported. It was found that the triazenido group acts as a monodentate ligand. Complex 1 in solid state has a S - cis -structure with NiN(3) σ-bond and exists as a 3:1 mixture of two isomers with cisoid or transoid orientation of the Me group of the o -tolyl ligand relative to the N(1)N(2) bond. It was established that the N , N ′-migration of ( o -Tol)Ni(PEt 3 ) 2 group occurs in a solution of 1 . The migration rate increases with the temperature increase in the range from −104 to −45°C. However, a further increase in the temperature slows down the process.