Home – Home – Jornals – Numerical Analysis and Applications 2020 number 1

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The energy efficiency of Russia’s economy and its eastern regions lags behind that of developed countries, and its growing is one of the overarching priorities set by the Russian state energy policy. The Baikal region has a special economic status as a world heritage site. The relevance of energy efficiency growing in the region is determined by the energy-intensive industry specialization of the economy and high environmental requirements to preserve the nature of Lake Baikal. The study objective is to forecast the GPR energy intensity dynamics in the Baikal region taking into account the energy cooperation between Russia, China, and Mongolia, as well as to identify the most significant factors affecting the energy efficiency of the region’s economy. As a result, we have devised a new methodological approach to energy efficiency assessment based on a combination of economic and mathematical modeling, system analysis, statistical analysis, balance and indicative techniques. The research tool is a data processing system designed to generate regional fuel and energy balances (FEB), which includes the following: a system of models and databases to analyze and forecast alternative scenarios for the fuel and energy complex (FEC) development in regions, with regard to international cooperation; economic and mathematical models of FEB; methods for assessing the energy efficiency of regional economies; statistical methods to determine crucialfactors affecting energy efficiency; benchmarking methods to assess development potential. The study identified the most significant factors in increasing the energy efficiency of the economy of the Baikal region, these are: stronger energy cooperation with neighboring countries; the rational use of fuel and energy in the economic sectors and among the population; the use of energy-saving technological processes and equipment to reduce the specific costs of fuel and energy resources (FER) in their production, transportation and consumption; reduced FER losses and consumption for the needs of energy enterprises. Statistical methods have been used to develop equations for multiple regression of the gross regional product energy intensity and gross energy consumption in the Baikal region. The equations make it possible to predict the dynamics of indicators for the future until 2035.

The article presents the results of practical application of interval methods under the uncertainty of a direct production costs matrix in the regional input-output model. It presents the complete technological chain for solving a linear tolerance problem with the Shary’s method, which uses the recognizing functional of a solution set, as exemplified by an interval input-output model for the Republic of Tyva. In the text, we obtain a long-term sectoral forecast of the socio-economic development in the Republic of Tyva till 2035 based on the regional interval input-output model.

Information and communication technologies (ICT) are changing the structure of the entire economy by creating new markets and production techniques. The development of the ICT industry is an overriding economic policy priority in many countries, including the Russian Federation. The article explores the state of ICT in Russia and its regions and assesses regional determinants that affect employment dynamics in this sector, from an empirical standpoint. Under the current situation in Russia, the ICT contribution to the economy (2.6% of added value and 1.6% of employees) is much less than that in highly developed countries. The industry is unevenly distributed in terms of space, and its dynamics across various regions also differ. The Russian ICT market is highly and increasingly concentrated. The three dominating regions are Moscow City, St. Petersburg City, and Moscow Oblast; these areas account for more than a third of the ICT employment and almost two-thirds of its costs. Driven by theories on regional determinants affecting the development of high-tech companies, including the ones in ICT, we point out the significance of human capital, resources, infrastructure, institutions, demand, competition, and other factors that establish an innovation system to support technological and innovative development and base it on individual territories. This article estimates factors influencing the ICT growth at the level of individual Russian regions, quantified by the number of persons employed in the industry. We have considered such factors as region’s size, its economic development, peculiar economic structure, human potential, availability of financing, and state subsidies for ICT. Using a generalized method of moments with instrumental variables (the Arellano-Bond estimator), we conclude that the most significant factors positively affecting the number of ICT employees have been as follows: population size, the share of university students, GRP per capita, and the proportion of high-tech industry in manufacturing.

The article summarizes the transport system of the Far North districts and lands in Krasnoyarsk Krai, highlighting types of transport crucial for the population and industry in this region. Using natural neighbor interpolation and fuzzy overlay in ESRI ArcGIS, we have estimated area distribution of the integral transport accessibility indicator for the territory under study. The resulting indicator combines physical (time) and economic (tariff) distance characteristics for cargo and passenger transportation by different types of transport. We explain the features of vehicle operation in each of the selected areas of transport accessibility. The obtained indicator provides ground for further research on the scale and distribution of transport costs necessary for growing industries and daily life in the far northern territories of Krasnoyarsk Krai.

At the present day, there is no strict, systematized, and comprehensive list of determinants for the migration behavior of young people, despite this topic being relevant for the Russian regions due to the high number of young people migrating across the country. The authors present their original view of migration behavior as a function with determinants, selected according to various migration theories and confirmed by migration studies carried out in Russia and abroad, which made it possible to identify the main trends and peculiarities of young people’s migration behavior in the current context. We analyze youth migration in the Siberian Federal District, Altai Krai specifically, and reveal possible consequences of significant migratory outflows of young people to neighboring regions. The conducted analysis is based on Rosstat data and research of both foreign and domestic scientists in the field of migration.

The article analyzes regional differences in the occupational structure of employees. The source of data for the study is an online job database hosted on the Work in Russia website by the Ministry of Labour and Social Protection of the Russian Federation. Using the database, the authors have compiled the Top 100 list of the most demanded occupations in Russia. An investigation of demanded occupations by occupational groups revealed that the highest number of vacant jobs in Russia is observed for qualified workers, while the number for professionals and associate professionals is substantially lower. A region-specific analysis of vacancies showed that in May 2019 the highest number of vacancies was offered by employers in Moscow, Primorsky Krai, Moscow Oblast, Amur Oblast, and Krasnoyarsk Krai. We uncover considerable regional differences in the occupational structure of vacancies. Region-specific causes for the differences are industrial structure, natural resource capacity, military importance, and building of major objects in the region.

Innovation system failures and companies’ innovation performance have been discussed in a large body of literature. Few studies, however, consider the relation between these two indicators for the regions of different economic specialization. Previous research from abroad contributes to the classification of innovation system failures, it helps to identify system imperfections and understand their nature, but it is not sufficient to develop innovation policies. Regional differences in technological development and in the way of interaction between local actors determine the regional focus of our study. Regions with resource abundance and resource-poor territories differ in innovative performance, though their macroeconomic and institutional environment is similar. We examine two hypotheses in our study. First, we consider if companies in resource-rich and resource-poor regions differ in their estimates of innovation system failures. Second, we examine if these estimates affect firms’ innovation activity. We used empirical data from the telephone survey of500 commercial institutions from resource-rich (53.8%) and resource-poor regions (46.2%). We found out that firms in resource-abundant and resource-poor territories are very similar in how they estimate innovation system failures, which proves that the problem of underdeveloped market institutions in Russia is common for them both. Significant differences were identified in social capital, particularly in actors’ interactions to channel innovation. The second hypothesis was not confirmed: the entrepreneurs in the survey do not take into account innovation system failures and their decisions about innovations do not depend on the innovation environment. The study results are applicable to national and regional innovation policies and can be also used for regions of different economic specialization.

As recorded by the State Forest Fund, the Komi Republic possesses the most forest resources in the European part of Russia, ranking first among other regions. However, while the official indicators exhibit positive dynamics, timber procuring business points out a decrease in the quality of forest resources regarding their commodity and species compositions, specific stock, properties of wood, and transport accessibility. This trend calls for a more objective assessment of the state and possibilities for improving the regional resource base so that it meets the current needs of forest management, including an assessment of compliance with sustainable development principles and criteria. The subject of this study is the state of forest resources in the Komi Republic. The purpose of our research is to evaluate the state of forest resources and the prospects for their use against the sustainable development criteria in forest management, using the author’s methodology based on national and foreign best practices. The scientific novelty consists in creating a system of indicators adapted to the forestry biological and economic background in the Komi Republic. Such a system should rely on data aggregation, extrapolation, and geosystem analysis as the research methodology. The study identifies the area of forests economically feasible for reforestation, as well as its possible economic effect. Taking into account the average annual stand growth per hectare and transport accessibility, we have divided the forest areas into groups and given each a description of the current state of forestry with prospects for the future. We provide recommendations for each group on forest management and use relevant to their natural and economic features. The results of this study are applicable to shaping the Komi Republic’s forest policy, forecasting in greater detail, and modeling forest use scenarios for districts in the Komi Republic. It may also serve as a methodological basis for the ecological and economic assessment of other heavily forested Russian regions.

The article discusses the current problems related to an emerging institutional environment for the social and economic development of municipalities. It shows that the socio-economic development of these units is accompanied by their high spatial differentiation. The economic policy and institutional mechanisms of its implementation fail to adequately consider regional peculiarities of the municipal economy and the unique role of the spatial factor in ensuring economic growth. To solve the problems described, we propose management mechanisms and tools providing an effective institutional environment and promoting the economic development of municipalities. The article covers methodological issues of shaping a favorable institutional environment for the development of municipalities, design principles of a management system for the development of municipalities, and features of economic modernization in rural municipalities. We have studied promising development trends for municipalities and investment policy, such as agricultural clusters, road construction, the revival of cooperation, and market infrastructure expansion. The article includes proposals on how to properly establish an institutional environment for the economic development of municipalities, aimed at improving the investment climate, modernizing the economy, raising living standards in municipalities, and improving the efficiency of regional and municipal management.

The article considers the role of large coal mining enterprises in the sustainable social and economic development within regions of operation, their influence on how the regional economy is managed, as well as the government’s opposing actions affecting coal business. This study is primarily based on the premise that business and public interests align in the long run. Sadly, shareholders and corporate executives are unlikely to be willing to narrow down their private interests when looking at long-term prospects. The results of our research show that the issues of accounting for the social consequences of coal mining activity by major industrial enterprises, the scope of their environmental and social impact, and their influence on the emerging public response to the activity of large corporate groups are subject to socioeconomic criticism. Virtually all coal mining companies claim to do socially responsible business, yet formal mechanisms do not confirm their statements. There is no comprehensive consideration of stakeholders’ interests, as only a few companies keep non-financial reports. Companies merging into corporate groups leads to unfair resource allocation and marginalization of coal-mining territories from the spotlight of social interest. As for establishing a uniform system of social responsibility, it is complicated by differentiated regional practices and weak public understanding. The main objective of the study is to identify mechanisms that could involve production in regional welfare and ensure positive interaction with stakeholders. It seems that such mechanisms will include both introducing and expanding public-private partnership programs, as well as legislating the duty of businesses to maintain non-financial reports, specifically for each region of operation.

This paper deals with the investigation of parallel SIMPLE (Semi-Implicit Method for Pressure Linked Equations) algorithm for the numerical solution of the Navier-Stokes system of equations for viscous incompressible flows. The interprocessor exchange mechanism with mesh decomposition with virtual cells and algebraic multigrid method is presented. The method of distributed matrix storage and the algorithm for matrix-vector operations reducing the number of interprocessor exchanges are presented. The results of a series of the numerical experiments on structured and unstructured grids (including the external aerodynamics problem) are presented. Based on the results obtained, the analysis of the influence of multigrid solver settings on the total algorithm efficiency was made. It was shown that the parallel algorithm for the SIMPLE method based on the algebraic multigrid technique proposed makes possible to efficiently calculate problems on hundreds of processors.

In this paper, we discuss a priori error estimates and superconvergence of splitting positive definite mixed finite element methods for optimal control problems governed by pseudo-hyperbolic integro-differential equations. The state variables and co-state variables are approximated by the lowest order Raviart-Thomas mixed finite element functions, and the control variable is approximated by piecewise constant functions. First, we derive a priori error estimates both for the control variable, the state variables and the co-state variables. Second, we obtain a superconvergence result for the control variable.

This paper deals with the derivation of the optimal form of the Rosenbrock-type methods in terms of the number of non-zero parameters and computational costs per step. A technique of obtaining ( m, k )-methods from the well-known Rosenbrock-type methods is justified. There are given formulas for the ( m, k )-schemes parameters transformation for their two canonical representations and obtaining the form of a stability function. The authors have developed L -stable (3, 2)-method of order 3 which requires two evaluations of a function: one evaluation of the Jacobian matrix and one LU -decomposition per step. Moreover, in this paper there is formulated an integration algorithm of the alternating step size based on (3, 2)-method. It provides the numerical solution for both explicit and implicit systems of ODEs. The numerical results confirming the efficiency of the new algorithm are given.

The mechanochemical method of producing supramolecular complexes of tebuconazole (TBC) was used to obtain new complex agents of plant protection from pests and diseases of cereal crops. The use of chitosan, as well as licorice root extract, in these processes made it possible to obtain preparations with improved physicochemical and biological parameters. Under field conditions, the high biological efficiency of the composition of tebuconazole with chitosan against Puccinia recondita, Septoria nodorum and Blumeria graminis was shown with a single treatment at the beginning of heading of spring wheat plants, which led to an increase in grain yield by 0.55 t/ha, while the dose of tebuconazole fungicide was reduced by a factor of 5.5. The possibility of making similar spring wheat protection products based on the combination of chitosan with licorice root extract without the inclusion of tebuconazole is demonstrated. This increases the grain productivity of wheat by 0.54-0.6 t/ha.

The reduction of silver nitrate in polyols in the presence of hydroxyethylated carboxylic acid as a stabilizer was investigated. The effect of synthesis conditions, in particular temperature, synthesis time, concentrations of silver salt, stabilizer, and sodium hydroxide, on the structural characteristics of the synthesized particles was studied by means of electron microscopy and X-ray diffraction. It was shown that large polyhedra 200-800 nm in size are formed in the system in the absence of the stabilizer, 2-[2-(2-methoxyethoxy)ethoxy]acetic acid (MEEAA). In the presence of MEEAA, silver nano- and microplates with the sizes ranging from 10-20 nm to 1 µm are formed, depending on synthesis conditions. The optimal reaction conditions were determined for obtaining silver plates 100-500 nm in size, with the dominating 200-300 nm fraction: temperature, 100 °C; synthesis time, 1 h; MEEAA to Ag molar ratio, 3 : 1. The type of polyol was shown to affect both the morphology of the resulting particles and the fraction of plates and polyhedra in the final product. Thus, the fraction of polyhedra with respect to the plates increases when passing from ethylene glycol to triethylene glycol and propylene glycol. The effect of the alkaline reagent (NaOH) on the composition, size, and morphology of reduction products was studied. It was shown that the rate of silver ion reduction increases significantly in the presence of NaOH, which allows carrying out the process at room temperature. At a molar ratio of NaOH to Ag equal to 4 : 1, nanoplates 10-20 nm in size are formed. As-synthesized silver micro- and nanoplates can be used in the development of conductive materials, including pastes and inks for printed electronics.

A solid-phase method was developed for the synthesis of β-tricalciumphosphate (β-TCP) with the stoichiometric composition and with partial substitution of calcium ions for copper, zinc and silver ions. The method involves preliminary preparation of precursors by means of mechanical activation of reaction mixtures. The start of β-TCP formation was detected directly during the activation of reaction mixtures in the mill. The optimal conditions for activation, the temperature and the duration of annealing were determined.

The anatase phase of titanium dioxide TiO₂ is metastable and irreversibly converts to rutile at a temperature above 700 °C. This is accompanied by a significant decrease in the specific surface area and a change in the porous structure. Modification of titanium dioxide by the addition of alumina leads to the formation of the nanocrystalline structure of anatase and to a significant increase in the temperature of anatase to rutile phase transition up to 950 °C. After high-temperature annealing, the Al₂O₃-TiO₂ sample is characterized by a higher specific surface area and a better developed porous structure than those of pure anatase with the regular crystal structure. The high thermal stability of the anatase phase in supported Pt/(Al₂O₃-TiO₂) catalysts under calcination provides a high dispersion of platinum particles, which leads to the rather high catalytic activity of these catalysts in CO oxidation.

The use of copper oxide complexes (CC) of various structures: CC-I (copper tetrammine complex with the ground state of copper ions (d_x² - d_y²), characterized by a weak exchange magnetic interaction in the EPR spectra) and CC-III (Cu²⁺ ions with the ground state (d_x² - d_y²), with the strong exchange magnetic interaction) in the synthesis of Cu/ZSM-5 catalysts allowed us to study the effect of their structure on the physicochemical and catalytic properties in the decomposition of nitrogen (I) oxide (N₂O). It was demonstrated by means of H₂-TPR and IR spectroscopy of adsorbed CO that the nature of the reduction of Cu/ZSM-5 catalysts is determined by the state of copper in the catalyst. It was established that the highest catalytic activity is observed for the catalysts prepared using CC-III. Extraframework CuO-like clusters stabilized on the outer surface of zeolite crystallites prepared using CC-III are the most effective centres for the decomposition of nitrous oxide, and the activity of catalysts increases with an increase in copper content.

Processing of the nitric solutions from the production of bismuth compounds by adding water was studied by means of X-ray phase and chemical analyses, and electron microscopy. It is shown that bismuth gets precipitated from solutions at the process temperature of 65±5 °C and pH 0.7-1.0 in the form of oxohydroxonitrate [Bi₆O₄(OH)₄](NO₃)₆•H₂O, and washing with water causes hydrolysis with the formation of high-purity [Bi₆O₅(OH)₃](NO₃)₅•3H₂O compound. These compounds are used as precursors for obtaining high-purity bismuth compounds through a solid-liquid reaction. It is demonstrated that the treatment of bismuth oxohydroxonitrate with the solutions of citric, gallic, tartaric, salicylic, nitric acids and ammonium carbonate may result in obtaining bismuth citrate BiС₆Н₅О₇, bismuth oxogallate trihydrate C₆H₂(OH)₃COOBiO•3H₂O, bismuth ditartrate trihydrate [Bi(C₄H₄O₆)(C₄H₅O₆)]•3H₂O, bismuth oxide salicylate Bi(C₇H₅O₃)O, bismuth nitrate pentahydrate Bi(NO₃)₃•5H₂O, bismuth oxocarbonate (BiO)₂CO₃, respectively. The powders of metal bismuth with particle size 1-5 and 10-50 mm were obtained by the reduction of oxohydroxonitrates of the compositions [Bi₆O₄(OH)₄](NO₃)₆•H₂O and [Bi₆O₅(OH)₃](NO₃)₅•3H₂O, respectively, in the solution of benzyl alcohol. The reduction of these oxohydroxonitrates in ethylene glycol solution in the presence of hydrazine hydrate in the case of [Bi₆O₄(OH)4](NO₃)₆•H₂O results in the formation of bismuth glycolate, while in the case of [Bi₆O₅(OH)₃](NO₃)₅•3H₂O - in the formation of metal bismuth with particle size 10-50 mm. The powders of metal bismuth with particle size 1-5 and 10-50 mm were obtained by means of the reduction of the compounds [Bi₆O₄(OH)₄](NO₃)₆•H₂O and [Bi₆O₅(OH)₃](NO₃)5•3H₂O, respectively, in the aqueous medium with sodium borohydride as the reducing agent, with the molar ratio of bismuth/sodium borohydride = 1, pH 12 and a temperature of 25 °C.

Recently, studies comparing various variants of operations to establish the optimal method of surgical treatment for chronic pancreatitis with pancreatic head lesions from the point of view of evidence-based medicine have been carried out in the world. However, these comparative studies do not take into account differences in the clinical and morphological forms of the disease, in particular, chronic pancreatitis with a predominant and isolated lesion of the head. Subtotal resection of the pancreatic head with proximal pancreatojejunostomy, suitable for an isolated lesion of the head, does not solve all the problems of chronic pancreatitis with a predominant lesion of the head. In this case, the violation of the outflow of pancreatic juice along the pathologically changed main pancreatic duct from the left half of the gland is not eliminated. It is impossible to unambiguously support the hypothesis of the feasibility of performing subtotal resection of the pancreatic head with proximal pancreatojejunostomy in chronic pancreatitis with a predominant lesion of the head with a uniformly expanded main pancreatic duct. With this form of chronic pancreatitis, cicatricial strictures can form in the main pancreatic duct, which can lead to ductal hypertension and serve as an indication for reoperation. The feasibility of using Beger operation in chronic pancreatitis with a predominant lesion of the head is doubtful, since the intersection of the isthmus and the need for a T-shaped longitudinal pancreatojejunostomy makes this intervention technically difficult and unsafe. Based on the studies performed, it is impossible to say with certainty about the reliable advantages of one type of operations over another. To obtain reliable results, it’s necessary to conduct evidence-based studies comparing subtotal resection of the pancreatic head with longitudinal pancreatojejunostomy with other types of interventions only for chronic pancreatitis with a predominant head lesion, excluding from the study patients with chronic pancreatitis with isolated head lesion.

Cement in joint replacement remains the main treatment method for patients with injuries and diseases of major joints. It allows eliminating patient’s pain, correcting the axis and length of the limb, to restore the supportability of the limb and return the patient’s activity. At the same time, it is a very complex treatment method, which requires careful preparation and a rather long postoperative rehabilitation period. Cement prosthetics are most often used in elderly patients with osteoporosis, and, as a rule, with the presence of comorbidities that complicate surgical treatment, and occasionally prevent its implementation. The study of morphological changes occurring in organs and tissues is a necessary step in the study of pathogenesis. Thorough knowledge of these processes allows to develop pathogenetically based methods of prevention or to choose the most appropriate method of treatment. This determined the purpose of the study: on the basis of morphological, experimental data to study the features of somatic and cognitive complications that occur during cement endoprosthetics of the knee and hip joints. An experimental model (95 Wistar rats) of a femur fracture was used to study the effects of intramedural administration of methyl methacrylate. The results were studied after 1 hour, after 1, 3, 7, 30 days. Histological studies (preparations of the femur, brain tissue, heart, lungs, liver, kidneys) were carried out according to standard methods. The results indicate the combined nature of the effects on the body: there is mechanical damage, thermal effects and toxic effects of the methyl methacrylate monomer. The experiment showed that «bone cement implantation syndrome» is not limited only to impaired function of the cardiovascular and respiratory systems, as well as data on impaired renal function, liver, and signs of postoperative cognitive dysfunction.

The incidence of chronic
myeloid leukemia from 2004 to 2018 amounted to 0.63 per 100 000 people
per year. The prevalence of chronic myeloid leukemia over the past 15
years has increased from 1.88 to 7.02 case per 100 000 people. We have
analyzed the therapy outcomes of chronic myeloid leukemia of patients,
received imatinib treatment for more than 12 month (165 patients).
Complete hematologic response is attained in 88.5 % cases (146
patients), complete cytogenetic response (CCR) (ph+<0 %) - in 72.1 %
cases (119 patients), major molecular response (MMR) - in 50.3 % cases
(83 patients). The primary resistance to imatinib is observed in 21.8 %
cases (36 patients), secondary - in 6.1 % cases (10 patients - 7
patients have lost the complete hematologic response and CCR and 3
patients have lost the CCR and MMR). The thirteen patients of those, who
have primary or secondary resistance to imatinib have been treated with
second-generation tyrosine kinase inhibitors (nilotinib, dasatinib) and
in 93,3 % cases (14 patients) CCR have been obtained, 10 patients (66.7
%) have attained the CCR and 9 patients (60 %) have achieved MMR. Among
all those patients treated with I and II generations tyrosine kinase
inhibitors, we have carried out the overall survival (OS) analysis and
obtained following results: the median of OS have not been achieved,
5-year OS rate is estimated as 90 %, 10-year OS rate - more than 77 %,
calculated 15-year OS - more than 60 %.

Aim of the study was to investigate the clinical features of reproductive age women with uterine body myoma and the production of vascular endothelial growth factor (VEGF) in the dominant myoma node and perifocal myometrium under the preoperative use of ulipristal acetate (UA). Material and methods. 140 samples of 35 women surgical material were studied, VEGF content in the incubation medium of samples of myoma and myometrium was measured using enzyme-linked immunosorbent assay. Results and discussion. The treatment by UA before myoma surgery according to the standard regimen per 5 mg daily for 13 weeks deals with significantly reduced production of VEGF in the dominant myoma node compared to perifocal myometrium ( p < 0.001), which is similar to patients of the control group. However, when comparing tumor nodes, a significantly lower content of VEGF was revealed in the UA-group ( p = 0.026); unlike the perifocal myometrium samples. Conclusion. The use of a selective modulator of progesterone receptors down-regulates the production of VEGF by the cells of the myoma nodes and doesn’t impact on the perifocal myometrium.

The aim of the study is to
evaluate the effectiveness of endosialoscopy in the diagnosis and
treatment of patients with sialolithiasis. Material and methods. 106
clinical observations were analyzed in which computed tomography
(multislice spiral computed tomography or cone-beam computed tomography)
without contrast, salivary gland ultrasound and endosialoscopy were
used to diagnose and treat patients with sialolithiasis. In the process
of diagnostic sialoscopy, the patency of the ducts, the presence of
strictures and dilatations, the condition of their walls, the severity
of the vascular pattern, the integrity of the epithelial lining, the
contents of the ducts, the presence of mucus, pus, and, of course, the
presence of sialolites, their number, size, shape, density were
evaluated. Results and discussion. Endoscopy allows you to get unique
information about sialolite and the state of the ductal apparatus, which
determines the method of further treatment. Endosialoscopy can be used
as a standard diagnostic method for suspected sialolithiasis and for the
removal of sialolites (using endoscopic instruments) or as assistance.
At the same time, diagnostic endosialoscopy is not an exhaustive method;
therefore it should be carried out in conjunction with other methods -
computed tomography or ultrasound of the salivary glands. The
possibility of endoscopic sialolite removal depends on its mobility,
size, location and condition of the duct. Attempts to capture and remove
fixed sialolites, which are only partially visible and located in the
deep sections of the salivary gland beyond the bend or stenosis section
using endoscopic techniques, have been unsuccessful.

The aim of the study was to
compare the potential of fast pulse sequences and traditional static
images for evaluation of temporomandibular joint (TMJ) biomechanics and
to optimize the magnetic resonance imaging (MRI) protocol of TMJ by
inclusion of dynamic scanning to improve the diagnosis of internal
derangements. Material and methods. Dynamic MRI with HASTE and true-FISP
pulse sequences was integrated into conventional MRI examination of TMJ
in 16 symptomatic patients with pain, restricted motion and clicking in
the joint. MRI was performed on superconductive 1.5 T scanner Magnetom
Espree (Siemens, Germany). The presence of motion and susceptibility
artifacts, range of mandible head motion and intrarticular disc location
in different jaw positions were analyzed when comparing static and
dynamic series. Results and discussion. HASTE was chosen for dynamic
functional MRI of TMJ because it was less prone to susceptibility
artifacts and provided better tissue contrast compared to true-FISP. Our
initial experience has demonstrated dynamic scanning to be a
time-efficient supplementary technique providing detailed information
about TMJ biomechanics during active jaw movements at a high temporal
resolution compared to traditional MRI examination. However, minimal
anterior disc dislocation could be missed on dynamic series due to poor
visualization of the posterior disc band on full closing. The further
optimization of dynamic scanning technique on a large patients group
using principles of the evidence-based medicine is needed. This would
allow improving the diagnosis and assisting clinicians to optimize
treatment strategy in a wide range of TMJ disorders.

The purpose of the study is
the development of indications and evaluation of the long-term results
of surgical treatment of benign tumors and dysplastic processes of the
mandible by the method of replantation of resected bone exposed to
extraorganic freezing. Material and methods. A method for the surgical
treatment of benign tumors and dysplastic processes of the mandible has
been developed. It involves resection of an afflicted by pathological
process segment of bone within healthy tissues, its mechanical
processing, freezing in liquid nitrogen followed by slow thawing, and
replantation. The evaluation of the treatment results has been carried
out on the base of clinical, radiation and functional research methods.
Long-term follow-up after surgery has been ranged from one to 25 years.
Results and discussion. Positive results of surgical treatment were
recorded in 72 patients (88,9 %). The indications for the developed
method use have been established. It was found that the reconstruction
of the mandible with a resected bone segment exposed to extraorganic
cryosurgery, eliminates the recurrence of a benign tumor, provides for
the restoration of the anatomical integrity of the jaw, and reduces the
invasiveness of the operation. Conclusion. Long-term clinical experience
has shown that mandible direct reconstruction in the surgical treatment
of benign tumors and dysplastic processes with the method of resection,
external freezing of the afflicted jaw area and its replantation is
available, simple, and highly effective and can be recommended in the
practice of medical institutions.

The aim of the study was to
assess the possibility of using a surgical approach - anterior sagittal
anoproctoplasty in children who had previously been operated with
various techniques for anorectal malformations. Material and methods.
The analysis of postoperative results was performed using a scale for
assessing the long-term results of treatment of anorectal malformations
before and after surgery. A retrospective study of the patients who was
previously operated for various forms of anorectal malformations for the
period from 2016 to 2019 in pediatric surgery department of State
Novosibirsk district hospital was performed. The early and long-term
outcomes were assessed. Results. The criteria for repeated surgical
treatment were: rectal mislocated outside of the sphincter mechanism,
low social adaptation, secondary changes from the perineum and external
genital organs. After investigation (identification of the sphincter
mechanism using a myostimulator, irrigoscopy, MRI or MSCT of the pelvic
organs), all patients underwent surgical correction - the anterior
sagittal anoproctoplasty. Postoperative results were assessed using
Holschneider score. The results obtained in the course of this study
indicate the possibility of using this method of surgical treatment.
Discussion. Children previously underwent surgery for anorectal
malformations but having severe functional disorders in the anorectal
region, are a complex group of patients who must be determined specific
criteria for the reoperations need. The efficiency of surgical treatment
depends on the presence of associated congenital malformations
(myelodysplasia, pathology of the sacrum and tailbone), as well as the
severity of cicatricial changes in the sphincter mechanism. Surgical
intervention in 33.3 % of cases led to satisfactory and in 66.7 % of
cases to good results.

Background. Urethral stricture is one of the most common complications after urethroplasty. And nowadays a growing number of congenital urethral diseases is observed. It is obvious that there is a huge amount of urethroplasty needed all over the world. Material and Methods. 15 patients with urethral strictures were included in the conducted prospective research. All patients underwent a complex urology investigation consisted of uroflowmetry, urethrography and urethroscopy. Most of strictures were located in penile urethra, their length varied from 1 to 5 mm. All patients enrolled in the study had the only single stricture. After investigation internal visual urethrotomy was performed with one-time stenting using individual prepared titanium nickelide stent. Stent was in urethra for 14-21 days. It had been evacuated from urethra and uroflowmetry, urethrography and urethroscopy were performed. Results and discussion. All patients have good result of uroflowmetry in the postoperative period. The results of urethrography and urethroscopy have also showed that there were no urethral strictures. The longest follow-up has lasted for 3 years. The efficiency of treatment is 93 %. The repeated procedure was required in one case. Any complications of this way of urethral stricture’s treatment haven’t occurred. Nowadays laser urethrotomy is known to have a success rate about 84 %, but follow-up period is still rather short. And also it is estimated that 65 % of all children with direct vision urethrotomy had a recurrence of the stricture in 5 years. It is hoped that the announced way of treatment of urethral stricture will be very perspective and will help to solve such significant problem in pediatric urology as urethral stricture. Conclusions. Stenting of urethra after internal visual urethrotomy has good outcomes, and seems to be a very perspective minimally invasive way of treatment of urethral stricture.

The aim of the study is to
assess the effect of systemic and local risk factors on the rate of
glaucoma progression, the specificity and informative nature of
ophthalmological studies for assessment of the rate of glaucoma
progression. Material and methods. A retrospective analysis of the
medical case histories and outpatient charts of 217 patients (268 eyes)
for the period from 2014 to 2017 was conducted. The patients with
primary open-angle glaucoma having at least 5 Humphrey field-of-view
(24-2) studies and optic coherence tomography of the optic nerve disk
and retina with a guided progression analysis (GPA) function (SD-OCT)
were included in the study. The patients were divided into 2 groups:
with rapid progression (more than 1 dB per year, 144 eyes (103
patients)) and slow progression (less than 1 dB per year, 124 eyes (114
patients)). The data of standard ophthalmological methods of
investigation (visometry, ophthalmoscopy, biomicroscopy, measurement of
intraocular pressure (IOP) according to Maklakov) were additionally
analyzed. Demographic and clinical data were assessed: gender, age,
cornea central thickness, refraction, IOP, glucocorticosteroid intake,
cardiovascular diseases presence, arterial hypertension, arterial
hypotension, local hypotensive therapy. Results and discussion. The
analysis revealed the main risk factors in glaucoma progression, which
include age, cardiovascular diseases presence, high initial IOP values,
pronounced functional changes in the visual fields (lower mean
deviation), pseudoexfoliation syndrome

Cavernous malformations
(CM), also known as cavernous angiomas or cavernomas, are benign
vascular hamartomas having a sinusoidal type of wall structure.CM occurs
in the brain stem with a frequency of 9-35 % of cases. They are most
often localized in the brain stem, have a higher risk of hemorrhage
compared to supratentorial. After the primary hemorrhage, the risks of
recurrent hemorrhages are very high. CM located in the brain stem has
not always been subjected to surgical treatment. Conservative treatment
was recommended for most patients. At the same time, according to the
literature data, mortality reached 20 %, and during radiosurgery up to
8.3 % with recurrence of hemorrhage up to 59 %. The aim of the study was
to evaluate the results of surgical treatment of patients with
cavernomas of the brain stem. Materials and methods. the study included
16 patients who had hemorrhages in different parts of the brain stem.
There were 12 males (75 %) and 4 females (25 %). Indications for
surgical treatment were: presence of subacute hematoma, recurrent
hemorrhage and progressive symptoms of brain stem damage. All patients
were operated using modern methods of microsurgery. Neurophysiological
monitoring was performed intraoperatively. Statistical processing was
carried out with the program Statistica (version 10). Results. There was
no operational mortality. At discharge, patients were assessed on the
Rankin scale. Good functional outcomes were achieved in 87.8 % of cases
(Rankin 1 - 43.8 %, Rankin 2 - 31.5 %, Rankin 3 - 12.5 %). Summary.
Symptomatic malformations of the brain stem are subject to surgical
removal when they are anatomically accessible. The use of modern methods
of neuroimaging, adequate, sparing surgical approaches, microsurgical
techniques for removing the cavernous brain stem, allows us to achieve
good functional results in the operated patients, in the absence of
postoperative mortality.

Objective of the study was to investigate clinical features of phenotypic variants of type 2 diabetes mellitus (T2DM) for personalization of hypoglycemic therapy. Material and methods. 2085 patients with T2DM (637 men and 1148 women), mean age 58.7 ± 6.9 years, duration of diabetes 7.8 ± 6.5 years; level of glycated hemoglobin (HbA1c), creatinine, urea, total cholesterol, triglycerides, low (LDL) and high density lipoprotein, uric acid, ALT, AST, insulin, C-peptide, microalbuminuria were examined. Depending on the level of C-peptide and the index of HOMA-IR, patients were divided into 3 groups: group of insulinopenic phenotype ( n = 250, 12 %), group of classical phenotype ( n = 1605, 77 %) and group of hyperinsulinemic phenotype ( n = 230, 11 %). Results. Patients with hyperinsulinemic phenotype differed from patients with classical and insulinopenic phenotype by later age of onset of diabetes (52.3 ± 8.1 years), high body mass index (BMI; 37.2 ± 7.4 kg/m²), blood LDL (3.38 ± 1.08 mmol/l) and creatinine level and frequency of chronic kidney disease (39.1 %). Patients with the insulinopenic phenotype had less diabetes duration (48.3 ± 7.9 years), a lower BMI (31.1 ± 6.3 kg/m²), higher blood glucose and HbA1c level and the frequency of diabetic polyneuropathy. Patients with the classic phenotype had a higher frequency coronary artery disease (20.8 %) compared to other phenotypes. Patients with insulinopenic phenotype on hypoglycemic tablets and patients with hyperinsulinemic phenotype on insulin therapy did not have HbA1c less than 7 %. Conclusions. To personalize therapy, the phenotypic variant of type 2 diabetes should be considered, with a study of the level of C-peptide, insulin and the calculation of the HOMA-IR insulin resistance index to determine the phenotype.

The purpose of the study was to assess the level of quality of life in the postoperative period in patients with bullous emphysema of the lungs operated on by «open» access and using minimally invasive technologies using the SF-36 questionnaire. Material and methods. The results of a survey of 50 patients with bullous emphysema were analyzed. The patients were separated into 2 groups depending on the method of access. The first group (main) consisted of the patients underwent video-assisted thoracoscopy, resection of a bulla-modified lung tissue, subtotal parietal pleurectomy. The second group (comparison) consisted of the patients underwent thoracotomy, resection of a bulla-modified lung tissue, subtotal parietal pleurectomy. The survey was conducted using the SF-36 quality of life questionnaire for 1, 3, 6 and 12 months. Results and discussion. The main indicators of the quality of life of respondents in terms of 1, 3 and 6 months after the intervention were statistically significantly higher in the group of patients who underwent thoracoscopy. Only a year after the operation, the main indicators of the questionnaire were not statistically significantly different between groups of patients, but the indicators of vital activity, social functioning, mental health and psychological component of health remained significantly higher in patients of group 1. The results indicate the need for long-term postoperative rehabilitation of patients with bullous emphysema lungs, operated in an «open» way. Follow-up survey with the specific questionnaires is required for more detailed assessment of the level of quality of life in patients with thoracic organs pathology.

The practical significance
of heparin low-molecular fractions as inhibitors of inflammation and
antithrombin III consumption reduction were studied. That is most
critical in acute hepatic failure. The study was performed using the
low-molecular-weight heparin (Nadroparin calcium) in low (prophylactic)
doses of 2000 anti-factor Xa units daily per 1 meter squared in the form
of continuous intravenous infusion. The cohort study proved the
nadroparin positive effect on carbohydrate and protein metabolism in
children with acute poisoning by hepatotoxic poisons, The significant
decrease in the quantitative assessment of disseminated intravascular
coagulation relative to the comparison group has been revealed, and the
decrease in 28-day mortality from 42 to 13 % has been found in children
receiving nadroparin. Conclusions are drawn on the feasibility of
introducing low molecular weight heparins into the intensive care
regimen of liver failure.

The aim of the study was to
investigate the nutritive status and identify risk factors for
cardiovascular disease in patients on hemodialysis. Material and
methods. 144 patients on program hemodialysis were examined. All
patients underwent general clinical and laboratory examination, lipid
profile was examined, body mass index was calculated, waist and hip
circumference was measured, ratio of waist circumference to the
circumference of hip was determined, abdominal integral multi-frequency
bioimpedansometry and multispiral computed tomography were performed.
Results. Gender features of distribution of abdominal adipose tissue and
dyslipidemia in patients on program hemodialysis were revealed. Women
have a predominant accumulation of visceral adipose tissue, while men
are characterized by a proportional distribution of subcutaneous and
visceral adipose tissue in the abdominal area. Women compared to men
have higher rates of atherogenic lipoprotein fractions, which level is
closely related to the volume of visceral adipose tissue. Among the
comorbidities in the examined patients, diseases of the cardiovascular
system predominate. The regression analysis revealed that the most
significant risk factor for the development of coronary artery disease
is an increase in low-density lipoproteins, for chronic heart failure -
an increase in waist circumference. Conclusions. The data obtained
indicate the need to monitor the nutritional status of patients on
hemodialysis to identify and correct risk factors for cardiovascular
disease.

The purpose of the study
was to investigate the main factors predisposing to the birth of
children at gestational age of 34-36 weeks, the features of the course
of the neonatal period, the structure of morbidity and mortality in the
conditions of the regional perinatal center. Material and methods. A
retrospective analysis of 380 medical records of an inpatient patient of
the Regional Perinatal Center of State Novosibirsk Regional Clinical
Hospital born on a gestational age of 34-36 weeks for 2017-2018 was
performed. Results and discussion. All women with premature late
delivery had a burdened somatic and/or obstetric-gynecological history.
70 % of women were delivered by surgery. The anthropometric
characteristics of late preterm infants in 85 % of cases corresponded to
gestational age, in most of them the neonatal period proceeded with the
development of respiratory disorders, hyperbilirubinemia, and low
tolerance to enteral nutrition. Children with less gestational age
needed respiratory support for a longer time. Due to the difficult
condition at birth, about 40 % of the children were transferred from the
maternity ward to the intensive care unit of the newborn. A quarter of
late premature infants received medical care exclusively in a maternity
hospital. The mortality rate was 1 %. Thus, late premature babies are a
special category of newborns, when nursing which it is necessary to
carry out timely diagnosis of pathological conditions, as well as the
prevention of adaptation disorders, especially in the early neonatal
period.

The aim of the research was to study the effect of genetic predictors of thrombotic/ischemic events in children with the developed complications and born mature or premature. Material and methods. A prospective follow-up monitoring of 47 patients (inpatients of the State Novosibirsk Regional Clinical Hospital) with thrombotic complications, the analysis of their medical records were carried out. The homeostasis system parameters, carriage of polymorphic variants of genes predisposing to thrombotic complications were accomplished for the children during the follow-up period. Results and discussion. Thrombotic and/or related ischemic events are more common in premature infants, herewith the severe cerebral ischemia and venous thrombosis localized in various vessels predominated over these complications. The state of the blood coagulation system in children with thrombotic/ischemic events is characterized by hypercoagulation shifts in the external and internal cascades of blood coagulation and accompanied by the increase in the D-dimers level. Among polymorphic variants of genes of hemostasis system the occurrence of polymorphic variant FV Leiden (rs6025) is higher in the study group compared to the European population (χ² = 7.454; p = 0.025). The obtained data indicate the need for extended diagnostic studies of hemostasis system and genetic search for «thrombogenic» predisposition in children, especially premature, residing in intensive care units for the presence of thrombotic readiness in order to timely predict the development of possible thrombotic and ischemic complications.

The aim of the research is to study nosological structure, features of kidney, lung damage, deaths in patients with ANCA - associated vasculitis underwent medical treatment in a multidisciplinary hospital. Material and methods. Selection and subsequent retrospective analysis of the medical histories of 38 inpatient patients observed in nephrological, rheumatological, pulmonological and surgical thoracic departments for the period from January 2012 to December 2018 were carried out. The disease main clinical symptoms, variants of the X-ray picture, and causes of death were assessed in the patients according to the clinical and laboratory examination. Results and discussion. The most common diagnosis was eosinophilic granulomatosis with polyangiitis (EGPA) - 16 cases; microscopic polyangiitis was diagnosed in 11 patients, granulomatosis with polyangiitis - in 9 persons. In 2 cases, ANCA-associated vasculitis was diagnosed without specifying the nosological form. The most common symptoms in patients with ANCA-vasculitis were fever, progressive shortness of breath, weakness, artalgia, eosinophilia, which occurred mainly in patients with EGPA. Among analyzed 38 cases, there were 6 men and 32 women. The average age of patients was 50.72 ± 12.6 years. There were 5 deaths and, in 2 cases, the outcome could not be clarified. All deaths occurred during the first year from the disease onset caused by infectious complications or severe manifestations of the main disease.

The purpose of the study
was to present the stages of effective nephrological service forming and
to evaluate the output results of the Regional Nephrological Center
(RNC) as the unit of multidisciplinary hospital. Results and discussion.
The nephrology service of State Novosibirsk Regional Clinical Hospital
began to form in 1978 with the opening of nephrology hemodialysis and
kidney transplantation departments. The RNC was established in 1993 on
the base of a territorial register for patients with chronic renal
failure. Currently, the RNC includes the department of nephrology, the
register for patients with chronic kidney disease (CKD) of 3-5 stages,
nephrological counseling office, offices for potential recipients of
renal transplantation and for patients with transplanted kidney, the
office of permanent outpatient peritoneal dialysis. As a result, the
prevalence and structure of CKD 3-5 stages in the Novosibirsk region are
comparable to those in Europe, the availability of the renal
replacement therapy, including the number of patients with a functioning
renal transplant exceeds the nationwide indicators. Conclusion. The
model of the nephrological service of a multidisciplinary hospital
provides accounting and dispensation of patients with CKD, increases the
effectiveness of treatment, including methods of renal replacement
therapy.