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A qualitative change in the risk profile after an episode of decompensated heart failure (HF) calls for an as immediate as possible therapeutic response. In the absence of uniform guidelines for the sequence and timing of administering the background therapy during the hospitalization period and the subsequent “vulnerable” period, clinicians have to rely on available expert opinions and results of conducted studies. The article focuses on an evidence base for the use of background therapy for HF during the above-mentioned periods. Special attention is paid to the conditions and principles of initiating this therapy.

Objective. Analysis of literature data of modern neurosurgical techniques in the treatment of lumbar disc herniation; clarification of the features of surgical tactics and results during microsurgical, endoscopic methods and laser thermoplastic of the intervertebral disk. Methods. A retrospective analysis of the results of conventional microdiscectomy (228 cases), laser disc decompression (22 observations) and percutaneos endoscopic discectomy (4 observations) for lumbar disc herniation from 2016 to 2018. The results of surgical treatment was assessed according to the Oswestry Disability Index (ODI), Visual Analog Scale (VAS), modified MacNab criteria, and morphometric data of MRI and CT scans during the preoperative and postoperative periods, as well as 6 and 12 months after surgery. Results. The result of the study was a comparison of the literature data with those obtained in our clinic in the treatment of patients using all the indicated methods. On our material, we received confirmation of the feasibility and perspectivity of using minimally invasive methods in the treatment of lumbar disc herniation with low probability of recurrence and repeated treatment for pain. Also agree with the statement that the techniques have limited application, especially with instability in the VMS and multilevel lesion. Conclusion. Endoscopic discectomy, as well as laser disc decompression, are minimally invasive methods of treatment lumbar disc herniation, and have become an alternative to open lumbar microdiscectomy, as they allow minimizing surgical trauma, the effects of surgery, and quickly regress pain syndrome, contributing to early post-operative activation of the patient. A personalized approach in the treatment of lumbar disc herniation is based on the competent selection of patients and the clarification of a number of factors in determining.

Art mediation is one of the topical museum practices of today. The article deals with the features of this phenomenon, outlining the prospects of its use in connection with the norms of museum legislation and world practice. Information about the studies of art mediation in Russia, as well as of its theoretical and methodological aspects, is provided. An experience of introducing art mediation methods in the museum institutions of Samara (as exemplified by exhibitions at the Zero Room Gallery, the Samara Literary Museum and the Art Nouveau Museum) is considered.

Paravertebral tumors of mediastinal localization an extensive group of pathological processes, the surgical treatment of which is carried out by doctors of various specialties, such as neurosurgeons and surgical oncologists. Currently, thoracoscopic removal is considered to be the most preferred method of surgical treatment of these mass formations, in view of the least trauma, fewer complications, and a reduction in the time of postoperative recovery of patients. A clinical case of surgical treatment of a patient with a giant paravertebral tumor originating from the 4th thoracic root is presented. The tumor was an incidental finding during routine fluorography. There were no focal neurological symptoms. Taking into account the topographic and anatomical features of the volumetric formation, the patient underwent a combined two-stage surgical intervention, where the first stage was laminectomy and removal of the foraminal component of the tumor from the posterior approach, the second stage was single-port video-assisted thoracoscopic removal of the mediastinally located tumor fragment. The operation was performed under conditions of a collapsed lung on the side of the intervention. In the postoperative period, no neurological deficit was noted; according to the control introscopy, the tumor was removed completely. According to the results of histological examination neurofibroma (Grade I).

In cardiological practice, there may be patients with chest pain and heart failure of a specific etiology, including an association with cardiovascular syphilis. This article describes a 49-year patient with chest pain, heart failure, and neurological symptoms associated with ongoing tertiary syphilis. The history included an antisyphilitic treatment 30 years before the current hospitalization. Further evaluation confirmed neuro- and cardiovascular syphilis with severe aortic regurgitation and syphilitic myocarditis. Tertiary syphilis is a rare but relevant challenge for various medical specialists, including cardiologists. This pathology requires increased medical alertness and interdisciplinary interaction for early diagnosis, effective and safe treatment, and improved prognosis.

In this paper, we study a composite material of the hybrid Al–Nb system fabricated by the method of severe plastic deformation by high-pressure torsion (HPT) up to 30 revolutions. To obtain a composite material, a three-layer Al–Nb–Al stack was subjected to deformation at room temperature on Bridgman anvils under a pressure of 5 GPa at N = 10, 25, and 30 revolutions and a deformation rate of ω = 1 and 2 rpm. The initial diameters of the pure aluminum and niobium disks, as well as the HPT conditions for the formation of monolithic and defect-free composite samples, were selected experimentally. The most intense crushing and mixing of niobium in aluminum occurred at an aluminum disk diameter of 10 mm and deformation conditions of N = 25 and 30 revolutions and ω = 2 rpm. After HPT under optimal conditions, three microstructural zones were observed in the samples: a central zone with wide curved niobium layers in aluminum, a zone in the middle of the radius with a finely dispersed banded structure, and a zone with a uniform distribution of niobium in an aluminum matrix at the periphery of the sample. The HPT was shown to lead to the formation of the Al3Nb intermetallic phase. The microhardness along the diameter of the obtained composite samples changed nonmonotonically and depended on the formed structure (microstructural zone).

It was found that the frequency of stress-induced somatic diseases in cadets during 45 training years increased from 0 in the I cours to 10% in the VVI courses. The first place in frequency is occupied by diseases of the digestive system (K00K93 according to the International Statistical Classification of Diseases and Related Health Problem 10th revision), during the training their level increased from 0 to 7.3%. Diseases of the circulatory system (I00I99) increased to 2.7%. Based on the psychophysiological, psychological and psychosocial indicators of the surveyed cadets, a discriminant analysis was performed and a linear classification function model for predicting the propensity to stress-induced somatic diseases was obtained. The model is statistically significant, the percentage of correct classifications is 95.8%, that indicates a good separation ability of this model. The stability of the model indicators during the entire training period is shown, so that makes it possible to use it as a prognostic model and apply to identify propensity of the junior cadet to developing stress-induced somatic diseases. Timely identification of cadets who are prone to developing stress-induced somatic diseases and personalized approach to psychological correction will contribute to the prevention of somatic health disorders, the increasing of efficiency and reliability of activity and the professional longevity of future military specialists. The indicators included in the model shows that the propensity to stress-induced somatic diseases is determined by both innate features (the speed of nervous processes and the ratio of inhibition and stimulation in the central nervous system, typological properties of the personality), and acquired skills of social behavior (coping models and psychosocial characteristics of the personality), as well as stress-induced neurotic manifestations which accumulated in the process of personal development. Psychological correction should be aimed at awareness and self-disclosure of their personal characteristics while developing the desired behavioral and social interaction skills, as well as training in mental self-regulation skills.

Enhancement of mining performance is inseparable from blasting improvement. The quality of rock fragmentation by blasting for further processing and manufacture of final products governs the rate and efficiency of adva nce in the mining sector. The analysis of promising approaches to improvement of quality of rock fragmentation by blasting shows that the main way is to use modern physical fields to intensify detonati on processes, for instance, to utilize cumulative effect of blasting. The authors have designed a shaped charge with cumulative effect, which allows making the bench bottom lower and enables the blasting expenses to be reduced. With this charge design, an explosive charge is located immediately above the bench bottom, which increases the detonation wave impact on the bottom. The shaped charge generates a jet that creates a shock wave directed downward and sideways from the borehole. The stress waves directed upward from the shaped charge ensure additional fragmentation of overlying rocks. Direction of some explosive charge energy to the bottom of the borehole extends the time of the blast energy effect on enclosing rock mass and creates two stress waves. The proposed technology allows also decoupling of explosive charges with an inert gap. The lower charge element is made of an explosive conformable with the strength characteristics of rocks in the bench bottom, and the upper part of the charge is to conform with the blastability category of the bench rocks. Making a charge cavity at the bottom of the borehole allows having influence on the intensity of rock fragmentation by blasting. Efficient parameters of the charge cavity in the shaped charge design are determined.

Severe plastic deformation has proven to be a promising method for the in situ manufacturing of metal-matrix composites with improved properties. Recent investigations have revealed a severe mixing of elements, as well as the formation of non-equilibrium intermetallic phases, which are known to affect physical and mechanical properties. In this work, a multilayered aluminum–magnesium (Al-Mg) nanostructured composite was fabricated using constrained high-pressure torsion (HPT) in a Bridgeman-anvil-type unit. A microstructure investigation and X-ray diffraction analysis allowed us to identify the presence of intermetallic Al3Mg2 and Al12Mg17 phases in the deformed nanostructured composite. The sputtering yield of the Al3Mg2 and Al12Mg17 phases was found to be 2.2 atom/ion and 1.9 at/ion, respectively, which is lower than that of Mg (2.6 at/ion). According to density functional theory (DFT)-based calculations, this is due to the higher surface-binding energy of the intermetallic phases (3.90–4.02 eV with the Al atom removed and 1.53–1.71 eV with the Mg atom removed) compared with pure Al (3.40–3.84 eV) and Mg (1.56–1.57 eV). In addition, DFT calculations were utilized to calculate the work functions (WFs) of pure Al and Mg and the intermetallic Al3Mg2 and Al12Mg17 phases. The WF of the obtained Al-Mg nanostructured composite was found to be 4 eV, which is between the WF value of Al (4.3 eV) and Mg (3.6 eV). The WF of the Al12Mg17 phase was found to be in a range of 3.63–3.75 eV. These results are in close agreement with the experimentally measured WF of the metal matrix composite (MMC). Therefore, an intermetallic alloy based on Al12Mg17 is proposed as a promising cathode material for various gas-discharge devices, while an intermetallic alloy based on Al3Mg2 is suggested as a promising optical- and acoustic-absorbing material.

Multilayered bulk Al–Cu–Al metal-matrix composite was fabricated by means of high-pressure torsion and subsequent annealing. The resulting composite had a heterogeneous structure consisting of ductile aluminum matrix and hard intermetallic inclusions with a gradient decrease in grain size and layer thickness when moving from the center to the periphery of the sample. Precipitation of $$\hbox {Al}_{2}\hbox {Cu}$$ intermetallic phase was revealed at the edge of the sample in the as-deformed state. Post-deformation annealing initiated the emergence of AlCu and $$\hbox {Al}_{\mathrm {4}}\hbox {Cu}_{\mathrm {9}}$$ intermetallic precipitates with increased hardness compared to strain-induced $$\hbox {Al}_{\mathrm {2}}\hbox {Cu}$$ particles. The growth kinetics of intermetallic compounds was obtained using precise X-ray phase analysis. It was found that the initial growth of intermetallic phases at temperatures 150–210 $$^{\circ }$$ C depends on time $$t^{1/2}$$ , indicating the bulk diffusion-controlled growth. The growth activation energy of Al $$_2$$ Cu and AlCu phases was calculated to be 0.48 and 0.33 eV, respectively. The results obtained contribute to an understanding of the kinetics of annealing-induced growth of intermetallic phases and the corresponding evolution of strength characteristics in Al–Cu–Al composites. It was revealed that thermal treatment regimes resulting in enhanced mechanical properties are associated with moderate time and temperature of annealing, which allows avoiding partial dissolution of strengthening phases. The applied approach of phase kinetics analysis can become the basis for the development of new energy-efficient heat treatment modes of in situ Al-based composites allowing to govern their heterogeneity type and tailoring the mechanical properties of the material.

A hybrid composite material fabricated from the Al – Nb system using severe plastic deformation by high-pressure torsion (HPT) up to 30 turns has been studied in the present work. To fabricate the composite, deformation of a three-layer Al – Nb – Al package was carried out at room temperature on Bridgman anvils with grooves under a pressure of 5 GPa at N = 10, 25 and 30 revolutions, at a strain rate of ω = 1 and 2 rpm. Initial disc diameters from pure metals and HPT conditions were experimentally optimized to obtain monolithic and defect-free composite samples. The most intensive fragmentation and stirring of niobium in the aluminium matrix was observed if diameter of aluminium discs was 10 mm and deformation conditions N = 25 and 30 revolutions and ω = 2 rpm were applied. Three microstructural zones were observed after HPT under optimal conditions: the central zone with wide curved layers of niobium in aluminium, the mid-radius zone with finely dispersed layered structure, and periphery with a uniform distribution of niobium in the aluminium matrix. It was shown that HPT led to formation of the intermetallic Al3Nb phase. The microhardness measured along the diameter of the obtained composite materials changed nonmonotonically depending on the produced structure (microstructural zone).

The main point of successful manufacture of metallic composites by direct bonding of dissimilar materials is achieving a homogeneous interface bonding. Two different types of deformation techniques for fabrication of metal composites were investigated. The first one was developed on the basis of high pressure torsion associated with a high energy impact on the material where part of energy involved can be dissipated via non equilibrium phase transition realization. This deformation due to high shear deformations allows not only to form a nanostructure, but also to bond dissimilar metals. Moreover, this method allows for a relatively short time and in a number of compounds to receive in one step at room temperature monolithic composites of sufficient size to certify the structure and properties. The second technique is diffusion bonding which integrate one material with the other by pressure under high temperature. In order to clarify the bonding mechanism by plastic deformation of dissimilar materials, the microstructural and some mechanical properties were studied in the processed samples.

Objective. To evaluate clinical outcomes, safety, and technical peculiarities of percutaneous endoscopic transforaminal and interlaminar removal of the lumber spine cranially migrated disc hernias. Material and Methods. In 2015–2018, percutaneous endoscopic transforaminal and interlaminar removal of cranially migrated hernias of the lumbar spine was performed in 53 patients (23 men and 30 women): 2 (3.8 %) at L2–L3 level, 13 (24.5 %) at L3–L4, 18 (34.0 %) at L4–L5, and 20 (37.7 %) at L5–S1. The age of patients ranged from 25 to 76 years and averaged 43.4 ± 11.6 years. Transforaminal approach was performed at the L4–L5 level and higher (62.3 % of cases), and interlaminar approach – at the L5–S1 level (37.7 %). Based on MRI, hernias with cranial migration were divided into zones: zone I – hernias with migration to the lower edge of the superjacent vertebra pedicle – 21 (39.6 %) patients; and zone II – hernias with migration above this border – 32 (60.4 %). Results were evaluated using ODI, VAS, and the McNab scale. Statistical analysis of VAS indicators (leg and back pain) and ODI scores before and after surgery was performed using the R and Microsoft Excel 2007 software. Results. Data collection was carried out using patient questionnaires at in-person examination, telephone interviews and electronic communications. Follow-up data of different terms were monitored in all patients. In one case (when mastering this technology), at the second stage, microdiscectomy was performed at the L4–L5 level for a residual hernia fragment in migration zone II, and in another case, a conversion into microdiscectomy was performed at L3–L4 level with a hernia in zone II due to lack of venous bleeding control in a patient receiving anticoagulants. In other patients, the mean VAS scores of preoperative radicular and axial pain decreased from 7.5 ± 1.4 and 3.8 ± 1.2 to 1.4 ± 1.2 and 3.5 ± 1.3, respectively, on the next day, to 1.7 ± 1.4 and 3.2 ± 1.1 in 1 month, to 1.5 ± 1.3 and 2.8 ± 1.4 in 6 months, to 1.6 ± 1.2 and 2.0 ± 1.3 in 12 months, and to 1.6 ± 1.2 and 2.0 ± 1.3 in 24 months after surgery. In the long-term follow-up period, no radicular leg pain was observed in any patient. According to the McNab scale, up to 6 months treatment results were assessed as excellent by 19 (35.8 %) patients, and as good – by 32 (60.3 %). In the case of lumbar pain in the long term period, blockade of facet joints and radio- frequency ablation of the medial nerve branch were performed. Relapse of hernias and instability of the operated spinal segment were not revealed. The average ODI score improved from 66.4 ± 7.2 to 20.5 ± 3.2 in 1 month, to 13.6 ± 2.1 in 6 months, to 12.4 ± 2.3 in 12 months, and to 12.4 ± 2.3 in 24 months after surgery. Conclusion. Percutaneous endoscopic transforaminal and interlaminar discectomy for cranially migrated lumbar disc hernia, while adhering the surgical technique target and exclusion criteria, is a safe and effective method, avoids excessive resection of the bone-ligamentous structures of the spine, can prevent iatrogenic instability of the spinal motion segment, and promotes early postoperative activation and recovery of the patient. Cranially migrated disc henias have a low probability of recurrence.

Multilayered Al-Cu composites were fabricated successfully by constrained high-pressure torsion (HPT) in a Bridgeman anvil type unit under an applied pressure of 6.0 GPa after ten turns. Due to the good strain compatibility of Al and Cu, achieved during HPT, separate discs bonded without pores and cracks. Microstructural characterization of the processed disks showed that the originally flat interface between Al and Cu layers transforms, and some bindings and vortice-like folding are formed in a submicron multilayered structure embedded in an Al-rich matrix in almost all volumes. This led to an exceptional increase of ultimate strength. The tensile tests showed the value of the tensile strength reached 485 MPa at room temperature, which is several times higher than in pure aluminum (80 MPa) and copper (190 MPa) subjected to the same processing. Such an increase in the ultimate strength is associated with hardening due to formation of a multiphase fine-grained structure. This study indicates a high potential for the application of high-pressure torsion in bonding of Al and Cu to produce composites with enhanced mechanical properties.

Based on the integrative interpretation of the Federal Law «On Education in the Russian Federation» and a number of positions of foreign and Russian scientists, this article comprehensively examines the essence of a simulated virtual educational environment. In the framework of the presented analysis, being a lecturer at a military university, the author actualises the problem from the standpoint of ensuring the qualitative growth of the potential of higher military education, where the formation of professional competency of future army offi cers via innovative technologies is deemed the key factor. The article emphasises that out of the existing educational media only the technosphere of e-learning is enshrined in the federal Law «On Education in the Russian Federation « (Article 16, Clause 1), i.e. the information presented in the databases and the infrastructure for its accumulation, storage and transmission, while the content and application methods along with the forms of e-learning are overlooked. In this regard, the article is focused on understanding the essence of a simulated virtual educational environment and learning tools in it. As a result of the analysis, the author comes to the conclusion that such environment is created not only with the help of information and communication technologies, but also with the intellect and imagination of a person, highlighting the duality of the essence of the virtual environment, its external and internal material and ideal manifestations.

It is recognized worldwide that the teaching staff is the determining factor in the quality of school education. The article uses the example of Primorsky Krai as an example to discuss a relevant for Russia problem of staff resources in the system of school education and to analyze the factors that can affect its solution. It is important to solve the personnel problems of regional education systems by relying on the experience of regions and leading countries taking into account the context. The goals of the national project „Education” cannot be achieved without solving the personnel problem in the industry. On the example of a specific region, the problem of providing schools with teaching staff was analyzed, key indicators of the quality of staff resources in the regional education system and the factors affecting it have been identified. The research used statistical data, studied the laws and other regulations, official reports (open data) and data from monitoring conducted by the authorities in accordance with the legislation on education, as well as materials from surveys of students studying under teacher education programs.