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Background. Accurate calculation of the volume of subdural hematomas of traumatic, vascular, and other origins during diagnosis is complicated which leads to difficulties in selection of optimal tactics of neurosurgical treatment. Aim. To preform comparative analysis of accuracy of different methods of subdural hematoma volume calculations to increase the quality of evaluation of the results of radiological methods in selection of surgical tactics.Materials and methods. Data from preoperative computed tomography of 20 patients (15 men and 5 women between the ages of 20 and 60 years) with confirmed diagnosis of subdural hematoma who were examined and treated at the Neurosurgery Clinic of the Kirov Military Medical Academy were used. Four groups were formed based of the calculation method: two groups using formulas for volume of ellipsoid or convexo-concave lens (the shape most accurately representing the shape of subdural hematoma); electronic algorithm of volume calculation (Gamma MultiVox D2 software, Gammamed-Soft, Russia); control method (manual sectional calculation of areas of the formed structures with subsequent summation).Results. Deviations between the obtained values varied between +18 and -16 %. Deviations for calculations using ellipsoid volume formula were +46 and -19 %; using convexo-concave lens formula +38 and -35 %, respectively. Electronic calculation algorithm (Gamma MultiVox D2) showed the best accuracy compared to other methods including the control method.Conclusions. Comparative analysis of the accuracy of the studied methods of calculation of subdural hematoma volume showed that median results are statistically similar which allows for selection and use of these methods in accordance with the neurosurgeon's preferences.Study of the algorithm based on ellipsoid volume shows low specificity of this method, comparatively high deviations of the results from the true value with a trend toward overprediction.Calculation using volume of convexo-concave lens showed intermediate result if the shape of the hematoma corresponded to the ideal chape of a figure enclosed between two segments of a sphere. In cases where the shape did not correspond to the convexo-concave lens, both overprediction and underprediction of hematoma volume were observed.Calculations using the Gamma MultiVox D2 software showed the highest accuracy, lowest range of deviation from the control data, best versatility, independence from both the shape and location of the subdural hematoma, as well as selection of a section used in other algorithms for the measurements.It should be noted that accuracy of determination of subdural hematoma volume by the studied methods is directly proportional to time necessary for calculation.

The cleaning of industrial gases from dust is one of the most significant current environmental protection problems. The search for new, more advanced and effective ways to clean dust gases and dust collector designs is based on the diversity of technological conditions for dust formation, the physicochemical properties of gases and trapped particles, and an increase in technical and economic requirements for cleaning processes. When cleaning hot or chemically aggressive gases and capturing abrasive dust, the use of electrostatic precipitators, bag, fibrous and granular filters is often associated with difficulties in protecting the devices from harmful factors or ensuring sufficient cleaning efficiency. The design features of slotted filters permit their use in solving such problems. An engineering method for calculating slotted filters developed on the basis of theoretical ideas and experimental studies is used to model and design slotted filters with specified performance indicators to ensure high cleaning efficiency and low hydraulic resistance. This technique is based on theoretical patterns of filtration using basic dust particle deposition mechanisms on isolated cylinders in relation to the stationary stage of the filtration process. A computer program that simulates the process of cleaning dusty gases in slotted filters has been developed. This makes it possible to determine the optimal operating parameters, design dimensions and regeneration conditions of slotted filters based on a specified cleaning efficiency and hydraulic resistance, taking into account the properties of dust and gas during prolonged continuous operation of the filter.

Bacterial biofilms play a major etiological role in dental diseases worldwide. Currently, toothpastes with bactericidal chemicals and abrasive materials are used as preventive care methods. However, chemicals can cause adverse side effects, with the use of antibiotics, fluorides, and antiseptics drastically reducing quality of life. At the same time, the rational design of bulk toothpaste materials has remained unexplored. In this work, we demonstrated a mechano-bactericidal strategy as an antibiotic-free and tooth-safe approach for dental biofilm elimination based on shape-anisotropy CaCO

The problem of healing of postoperative wounds in oncologic patients remains relevant still the present time. After laryngectomy the percentage of primary healing of postoperative wounds does not exceed 40–60%. After surgical intervention there are favorable conditions for the activation of pathogenic microorganisms of the pharyngeal mucosa. The aim of our study was to develop preventive measures to reduce the percentage of healing of postoperative wounds by means of secondary intention after laryngectomy. The course of prevention consisted in daily treatment of the pharyngeal mucosa with successively freshly prepared ozonated saline solution with an ozone content of 0.15 g/l in an amount of 3 ml; and then with a bifidobacteria probiotic in in an amount of 2 ml. After this course of prevention, the number of pathogenic and opportunistic microorganisms decreased on the pharyngeal mucosa, bifidobacteria and lactobacilli appeared. Preoperative preparation for laryngectomy by irrigation of the pharyngeal mucosa with ozonated saline solution and probiotic helps to reduce the number of local complications of infectious origin by 16.7% of cases. There is no negative effect Bifidobacterium longum MC-42 on long – term oncological.

The article discusses the problems that arise when engineering classes are organized in secondary schools with participation of universities, and ways to solve them. To strengthen the connection between the school and the university, it is necessary to use both methodological and technological capabilities. The analysis of topics close to the standard programs of higher engineering education, which have appeared recently in the school curriculum in mathematics, is carried out. Methods have been proposed for wider engagement of intellectual capacity of university staff by involving them in creation of teaching methods in schools and especially in the in-depth study of mathematics in engineering classes. The experience of a special mathematical seminar organized by university departments of mathematics for school teachers of engineering classes is considered.

To academic film science

For the English abstract and full text of the article please see the attached PDF-File (English version follows Russian version).ABSTRACT The article deals with the features of the transition zone from the ballast under-sleeper base to the bridge structure with various types of span structures, as well as the sections of the ballastless track, conjugated with the transient zone. An analytical model is proposed for describing the dynamic behavior of a railway track in the form of a transversely isotropic plate with variable rigidity parameters. Examples of the use of the proposed model for calculating the dynamic depression of a roadbed under the influence of a rolling stock with different freight and speed characteristics are given. Keywords: railway, bridge, roadbed, residual deformation, variable rigidity section, track depression, slope, elastic wave, track profile, transversal-isotropic plate.

The results of investigation of the microstructure of composite coatings produced by carbo-vibroarc surfacing using cermet pastes are presented. It is shown that the composite cermet coating consists of two zones – the main and transition. The main zone of the coating contains the Fe2B hardening phase with nickel and chromium atoms implanted in the crystal lattice of the phase. The zone is situated in the matrix of the solid solution of iron and nickel Ni3Fe. The transition zone of the coating is formed by the mutual diffusion of the coating and the substrate and consists of the (Fe, Ni)2B hardening phase and the Ni3Fe matrix. It is also shown that the hardening phases form plate-shaped grains with thicknesses of 1–4 μm and more than 100 μm long, distributed in the form of colonies throughout the entire volume of the coating zone. In the direction to the transition zone, the shape of the structural components changes to circular with the diameter of up to 5 μm.

[For the English abstract and full text of the article please see the attached PDF-File (English version follows Russian version)].ABSTRACT Using the methods of statistical analysis based on the theory of random process emissions, the theory of random point processes, the method of least squares, the method of least modules, filtering algorithms, the choice of a type of a theoretical function and its parameters that allow reducing the error of the measured characteristics of defects and deviations of the track from the design position, a mathematical model is formulated that provides an increase in the informative value of the assessment of the actual state of the railway track. High information value is needed primarily for formation of adequate control actions on the track in order to ensure traffic safety. Keywords: railway track, measured parameters, information-measuring system, defect detection, statistical analysis, theory of random processes, mathematical model.

The calculation method that yields rational ratios of the thickness of the filter layer and the rate and time of filtration of a slotted filter that provide the target cleaning efficiency of dusted gases in processes at a constant filtration rate has been proposed. The method is based on the concepts of stationary factor and residence time of dusted gas in the filter layer; it considers the efficiency decrease caused by the secondary dust entrainment. It helps to determine the necessary data for the design of a slotted filter that has any target capacity and cleaning efficiency.

We investigate the dynamic spectra of the Sun and jovian decametric radiation obtained by the authors with the radio telescopes UTR-2 and URAN-2 (Kharkov, Poltava, Ukraine). We focus on the similar structures that appear on the dynamic spectra of those objects: S-bursts, drifting pairs, absorption bursts and zebra patterns. Similarity in structures allows us to assume that the plasma processes in the solar corona and in the jovian magnetosphere might have similar properties. We analyze and compare the main parameters of those structures and describe briefly some mechanisms of their generation that have already discussed in publications. We selected the mechanisms which, in our opinion, most completely and consistently explain the properties of the structures under consideration.

Worldwide, there is a constant increase in mortality from malignant neoplasms, which is largely due to late diagnosis. One of the reasons for late detection is the lack of conditions for conducting a detailed examination at the outpatient level, since the routine method of examining ENT organs today remains examination using mirrors, but in recent decades, endoscopic methods of examination have become widespread - indirect endoscopy, fibrolaryngoscopy, contact endoscopy, NBI-endoscopy, endoscopy using light filters of the SPIES system, as well as diagnostics using fluorescent technologies. Also, a promising and new direction is the diagnosis of malignant neoplasms at the preclinical stage and precancerous conditions, for which molecular diagnostic methods are used - SCCA and microRNA.To analyze the effectiveness of various methods of endoscopic and molecular diagnostics of malignant neoplasms of the larynx and pharynx.A study was conducted In the Department of ENT Oncology of the National State Research Center of Otorhinolaryngology of the Federal Medical-Biological Agency of Russia, which involved 46 patients with suspected malignant neoplasms of the larynx and pharynx. All patients underwent direct laryngoscopy under endotracheal anesthesia with simultaneous NBI-endoscopy, spies examination, contact endoscopy, and fluorescence testing, followed by biopsy and tissue sampling for microRNA concentration analysis, as well as blood sampling for SCCA concentration.Во всем мире отмечается постоянный рост смертности от злокачественных новообразований, что в значительной степени обусловлено поздней диагностикой. Одна из причин позднего выявления — отсутствие условий для проведения детального осмотра уха, горла и носа на уровне амбулаторного звена, так как рутинным методом остается осмотр с помощью зеркал. В последние десятилетия широкое распространение получили эндоскопические методы осмотра — непрямая эндоскопия, фиброларингоскопия, контактная эндоскопия, NBI-эндоскопия, эндоскопия с применением световых фильтров системы SPIES, а также диагностика с применением флюоресцентных технологий. Новым и перспективным направлением является диагностика злокачественных новообразований на доклинической стадии и предраковых состояний, для чего применяют молекулярные методы диагностики — SCCA и микроРНК.Провести анализ эффективности различных методов эндоскопической и молекулярной диагностики злокачественных новообразований гортани и глотки.В отделении онкологии опухолей головы и шеи ФГБУ «НМИЦО ФМБА России» проведено исследование, участие в котором приняли 46 пациентов с подозрением на злокачественные новообразования гортани и глотки. Всем пациентам выполняли прямую ларингоскопию в условиях эндотрахеального наркоза с одномоментным выполнением NBI-эндоскопии, осмотра с применением системы SPIES, контактной эндоскопии, исследования с применением флюоресцентных технологий, после чего осуществляли биопсию и забор тканей для проведения анализа на концентрацию микроРНК, а также забор крови для определения концентрации SCCA.При гистологическом исследовании у 31 (67,4%) из 46 пациентов выявлен плоскоклеточный рак, из них TНаряду с биопсией и последующим гистологическим исследованием эндоскопические и молекулярные методы диагностики зарекомендовали себя как эффективные дополнительные методы выявления патологии гортани и гортаноглотки.

We present a recently developed radar “OKO”, which is intended for all-weather, long-term operation under local or remote control. It can be used for various security applications, including perimeter protection, UAV detection and tracking. “OKO” is a Doppler radar with pulse compression and mechanically scanned antenna. An advanced clutter suppression, MTI, and CFAR algorithms are introduced in the system. The hardware and software solutions used in the radar are described along with the results of the radar field tests on the detection and tracking of ground and air objects.

[For the English abstract and full text of the article please see the attached PDF-File (English version follows Russian version)].ABSTRACT The authors evaluate the process of dynamic contact «wheel-rail» through analysis of several simulation models of interaction, allowing to take into account different rheological properties of contacting bodies. The research apparatus comprises equations describing the motion of wheel and rail in the vertical direction, which are then solved using initial conditions and numerical iterative scheme, assuming that at small time intervals individual values behave linearly. The proposed algorithm allows to determine that at medium and high speeds of vehicle movement the elastic-plastic dependence of Alexandrov- Kadomtsev is most appropriate to describe the nature of interaction between the wheel and the rail, as well as to find individual dynamic values. Keywords: railway, wheel, rail, dynamic effects, viscoelastic contact force, elastic-plastic interaction, mechanical characteristics, interaction patterns, dynamic bending, local buckling. REFERENCES 1.Agostinacchio, M., Ciampa, D., Diomedi, M., Olita, S.Parametrical analysis of the railways dynamic response at high speed moving loads.Journal of Modern Transportation, 2013, Vol.21, Iss.3, pp.169-181. 2.Fang, M., Cerdas, S.F., Qiu, Ya.Numerical determination for optimal location of sub-track asphalt layer in high-speed rails.Journal of Modern Transportation, 2013, Vol.21, Iss.2, pp.103-110. 3.Alexandrov, V.M., Romalis, B. L.Contact tasks in mechanical engineering [Kontaktnye zadachi v mashinostroenii].Moscow, Mashinostroenie publ., 1986, 362 p. 4.Kogan, A.Ya.Interaction of wheel and rail at rolling [Vzaimodejstvie kolesa i rel’sa pri kachenii].Trenie i smazka v mashinah i mehanizmah, 2008, Iss.8, pp.26-38. 5.Olsson, R., Donadon, M.V., Falzon, B. G.Delamination threshold load for dynamic impact on plates.International Journal of Solids and Structures, 2006, Vol. 43, pp.3124-3141. 6.Biryukov, D.G., Kadomtsev, I. G.Elastic-plastic nonaxisymmetric impact of parabolic body on a spherical shell [Uprugoplasticheskij neosesimmetrichnyj udar parabolicheskogo tela po sfericheskoj obolochke].Prikladnaja matematika i teoreticheskaja fizika, 2005, Vol.46, Iss.1, pp.181-186. 7.Loktev, A.A., Vershinin, V. V.Modeling shockproof insulation systems with viscoelastic elements [Modelirovanie sistem protivoudarnoj izoljacii s vjazkouprugimi elementami].Vestnik MGTU im. Baumana. Serija Estestvennye nauki, 2012, Iss.2, pp.52-63. 8.Loktev, A.A., Sycheva, A. V.Research of dynamic characteristics of the upper structure of railway track under dynamic action [Issledovanie dinamicheskih harakteristik verhnego stroenija zheleznodorozhnogo puti pri dinamicheskom vozdejstvii].Nauka i tehnika transporta, 2013, Iss.4, pp.58-64. 9.Loktev, A.A., Sycheva, A.V., Vershinin, V. V.Modeling of Work of a Railway Track at the Dynamic Effects of a Wheel Pair.Proceeding of the 2014 International Conference on Theoretical Mechanics and Applied Mechanics, Venice, Italy, March 15-17, 2014, pp.78-81 10.Mazov, Yu.N., Loktev, A.A., Sychev, V. P.Assessment of impact of defects rolling stock wheels on the state of the railway track [Ocenka vlijanija defektov koles podvizhnogo sostava na sostojanie zheleznodorozhnogo puti].Vestnik MGSU, 2015, Iss.5, pp.54-65. 11.Balandin, D.V., Bolotnik, N.N., Pilkey, W.D.Optimal protection from impact and shock: theory and methods.Applied Mechanics Reviews, 2000, Vol.53, Iss.9, pp.237-264. 12.Schonberg, W.P., Keer, L.M., Woo, T.K.Low velocity impact of transversely isotropic beams and plates.International Journal of Solids and Structures, 1987, Vol.23, pp.871-896.

[For the English abstract and full text of the article please see the attached PDF-File (English version follows Russian version)].ABSTRACT A mathematical model of wave surface propagation in the flat element, which is a carrier plate of ballastless track under dynamic action of wheel set, is demonstrated. An algorithm of accounting different rheological properties of interacting bodies, based on the analytical method of representation of unknown quantities in the form of expansions in terms of spatial coordinates and time, initial and boundary conditions, is offered. The method of constructing a wave pattern in the plate is based on the principle of superposition of two separate tasks: contact problem of initial dynamic load application and wave plate deformation problem over time, including through the dissemination of elastic waves with finite speeds. In the article the wave problem is solved in an analytical form for displacement functions. Keywords: dynamic impact, plate Uflyand-Mindlin-Reissner, elastic waves, orthotropic properties, spherical functions, ballastless railway track. REFERENCES 1.Abrate, S.Localized impact on sandwich structures with laminated facing.Applied Mechanics Reviews, 1997, Vol.50, Iss.2, pp.69-82. 2.Sycheva, A.V., Loktev, A.A., Zaletdinov, A. V.Calculation of depression in the subgrade surface [Raschet osadki polotna zheleznodorozhnogo puti ot dejstvija dinamicheskoj nagruzki s pomoshh’ju luchevogo metoda].Nelinejnyj mir, 2013, Iss.11, pp.67-76. 3.Loktev, A. A.Dynamic contact of a spherical indenter and a prestressed orthotropic Uflyand-Mindlin plate.Acta Mechanica, 2011, Vol.222, Iss.1-2, pp.17-25. 4.Olsson, R., Donadon, M.V., Falzon, B. G.Delamination threshold load for dynamic impact on plates.International Journal of Solids and Structures, 2006, Vol. 43, pp. 3124-3141. 5.Thomas, T. Y.Plastic Flow and Fracture in Solids.N.Y.; L.: Acad.Press, 1961. 6.Achenbach, J.D., Reddy, D. P.Note on wave propagation in linear viscoelastic media.Zeitschrift für angewandte Mathmetik and Physik, 1967, Vol.18, pp.141-144. 7.Biryukov, D.G., Kadomtsev, I. G.Elastic plastic nonaxisymmetric impact of parabolic body on a spherical shell [Uprugoplasticheskij neosesimmetrichnyj udar parabolicheskogo tela po sfericheskoj obolochke].Prikladnaja matematika i teoreticheskaja fizika, 2005, Vol.46, Iss.1, pp.181-186. 8.Zaletdinov, A.V., Loktev, A. A.Defining interaction points of direct and reflected waves in a plate [Opredelenie tochek vzaimodejstvija prjamyh i otrazhennyh voln v plastinke].Vestnik MGSU, 2010, Iss.4, pp.92-98. 9.Malekzadeh, K., Khalili, M.R., Olsson, R., Jafari, A.Higher-order dynamic response of composite sandwich panels with flexible core under simultaneous low-velocity impacts of multiple small masses.International Journal of Solids and Structures, 2006, Vol.43, pp.6667-6687. 10.Agostinacchio, M., Ciampa, D., Diomedi, M., Olita, S.Parametrical analysis of the railways dynamic response at high speed moving loads.Journal of Modern Transportation, 2013, Vol.21, Iss.3, pp.169-181. 11.Abrate, S.Modelling of impact on composite structures.Compos Structures, 2001, Vol.51, pp.129-138.

The distribution patterns of mouselike rodent species within the ecological space of the mountain forest of the southern Middle Siberia and the formation of multispecies communities are considered on the basis of our long-term research and literature data. The significant factors of the three-dimensional ecological space were identified by using multidimensional statistical analysis (multidimensional scaling, cluster and canonical discriminant function analyses). The differences in the sensitivity of species to environmental factors were shown to cause a divergence of their ecological niches, which ensures the independence of these species within their community.

Some results of studying the cleaning of dusted air on a slotted filter at a constant filtration velocity were given. The efficiency of cleaning was related to the stationary factor and the time of residence of the dusted flow in the filtration bed. The conditions of the highly efficient cleaning of dusted gases in the steadystate filtration period and the method of selecting necessary process parameters and principal filter dimensions were determined.

It is shown that the solidification conditions in an entire continuously cast ingot cannot be controlled by varying the thermal conditions of cooling the ingot surface. The methods that can intensify the heat transfer in the solidifying melt should be applied in the most problematic axial zone of the ingot.

A computer model is constructed to describe the formation of nonmetallic inclusions in high-carbon bearing steel. The effect of the steel’s contents of aluminum, nitrogen, and oxygen on the formation of oxide and nitride phases during crystallization is analyzed, and it is established that the quantity of aluminum oxides formed depends non-monotonically on the aluminum content of bearing steel. Efficient deoxidation and microalloying with aluminum is proposed as an effective means of improving the quality of bearing steel.

Spatial distribution and size dynamics of the forest reindeer population in the central part of the Western Sayan for the period from 2004 to 2012 are studied. The territorial distribution of deer subpopulations; their migrations and age and sex structure; and the influences of abiotic, biotic, and anthropogenic factors are considered.

A relation between the kinetic parameters of the antiradical activity of aryl and hetarylhydrazones and their electronic structure is revealed in the form of the correlation between the reaction rate constants, bond energies of the reaction centers and the antioxidants ionization potentials. The relations obtained can be used to predict the antiradical activity in a series of hydrazones.

Microporous material with a large surface area is obtained through the controlled desolvation of 4-tert-butylcalix[4]arene complex with acetonitrile.

The objective of the study is to improve the efficiency of surgical treatment of patients with bilateral paralytic laryngeal stenosis. The article presents the experience of treatment of patients with bilateral post-surgical chronic paralytic laryngeal stenosis. The authors present description and assessment of clinical efficacy of the new method of paralytic laryngeal stenosis surgical treatment. The article provides the comparative analysis of the outcomes of therapy of the patients with such pathology depending of the surgery type.

The article presents a clinical case of a local tumor-like nasopharyngeal amyloidosis. The authors displayed a clinical picture of the disease, described the algorithm of examination of the patient that became the basis for diagnostic, illustrating the problems of histological examination of the biopsy material in details and providing the photos.

The development of medical technologies and the related interest of oncologists in organ-preserving treatment led to an increase in patients with cicatricial laryngeal stenosis after endolaryngeal resection. The development of the principles of prevention of scar deformities in patients after laryngeal resections is an urgent and important issue that needs to be studied. The article gives comparative characteristics of two methods of prevention of scarring in the area of anterior commissure of the larynx when performing endolaryngeal resections for cancer.

The fossil and modern faunas of small mammals from the end of the Pleistocene to modern times in the south of West and Middle Siberia were analyzed. It was shown that during the Sartan, the typical hyperborean complex of mammals was spread to the middle reaches of the Yenisei. In the northwest of Altai a hyperborean complex of mammals of the southern type existed at the end of the Pleistocene; it had its specific regional features. Warming and an increase in humidity in the Holocene led to the disappearance of the periglacial landscape and reduction of the area occupied by the tundra-steppe ecotopes. Expansion of the forest belt resulted in degradation of the hyperborean complex of mammals. In the second half of the Holocene, the formation of forest and forest-steppe complexes of small mammals took place.

The report describes the influence of mineral complex on economic stability and contains a strategic map demonstrating modeling of this influence.