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Ferritin is one of the key proteins, which has involved in the regulation of iron homeostasis in the body. Ferritin reduced values are often associated with changes in the total iron supply in the body. In addition, ferritin is involved in immune processes and can have both pro-inflammatory and anti-inflammatory effects. Ferritin changes in laboratory values is a rather nonspecific sign that occurs with immunoinflammatory and infectious diseases, as well as the development of iron overload. It can, among other things, accompany the course of new coronavirus infection (COVID-19) and chronic viral hepatitis C (CHC) in patients. Hyperferritinemia in these two diseases may be a marker of a more severe course and adverse patient outcome, making the study of ferritin levels an extremely important task for the practitioner. Therefore, the purpose of this review of the scientific literature was to investigate the possible relationship between Hyperferritinemia, COVID-19 and CHC. It has been reported that hyperferritinemia is quite often associated with a more severe form of both COVID-19 and CHC. Several studies have suggested that the risk of mortality may be increased if they are combined. In this regard, an important conclusion was made about measuring baseline ferritin levels with subsequent dynamic monitoring in this group of patients.

Aim. The study reviews current evidence on digestive system lesions provoked by the new COVID-19 coronavirus infection.Key points. Alongside the destructive impact on respiratory system, COVID-19 manifests itself in gastrointestinal symptoms (nausea, vomiting, diarrhoea) that may precede respiratory signs and prevail in the clinical picture of infection. Patients with chronic inflammatory bowel diseases receiving immunosuppressive therapy are at elevated risk of severe COVID-19 progression. The new coronavirus infection may induce liver damage with increased transaminase activity.Conclusion. Association of digestive system lesions with COVID-19 remains understudied and requires further research.

Rebamipide is a mucoprotective drug which was developed in Japan in 1990. The therapeutic effect of rebamipide based on the induction of cyclooxygenase-2 and increasing level of prostaglandins, inhibition of oxygen free radicals production, epidermal growth factor stimulation, vascular endothelial growth factor, nitric oxide, and decreasing of lipid peroxidation and neutrophils migration. The combination of proton pump inhibitors and rebamipide is more effective in relieving of gastroesophageal reflux disease symptoms and reducing recurrence rate of disease. Using rebamipide in the treatment of gastroesophageal reflux disease is justified because this drug has a unique mechanism of action, which eliminating the main stages of pathogenesis of the disease.Ребамипид это лекарственное средство, разработанное в Японии в 1990 г., основным механизмом действия которого является защита слизистой оболочки желудочно-кишечного тракта. В основе терапевтического действия ребамипида лежат индукция циклооксигеназы 2-го типа, повышение уровня простагландинов, уменьшение выраженности перекисного окисления липидов, ингибирование продукции свободных радикалов кислорода, стимулирование эпидермального фактора роста, фактора роста эндотелия сосудов, оксида азота, снижение уровня воспаления путем ингибирования факторов активации нейтрофилов и молекул адгезии. Комбинация ингибиторов протонной помпы и ребамипида является более эффективной в купировании симптомов гастроэзофагеальной рефлюксной болезни и снижении частоты рецидивов заболевания по сравнению с монотерапией ингибиторами протонной помпы. Использование ребамипида в терапии гастроэзофагеальной рефлюксной болезни оправдано ввиду наличия у этого препарата уникального механизма действия, направленного на устранение основных этапов патогенеза заболевания.

With the introduction of polygon site technologies, the extension of locomotive circulation areas has increased the complexity of solving the problems of regulating the fleet of locomotives. Determination of the required rational size of the irreducible reserve of locomotives at the stations of its turnover is currently carried out in order to extinguish the influence on the export of the inaccuracies in the planning and inadequate depth of the forecast of the car traffic flows. Substantially this determination is made on the basis of expert assessments and does not have sufficient methodological justification. In order to exclude the loss of the traffic threads in the schedule, it is necessary to create a rational irreducible reserve of locomotives at the stations of its turnover. To solve this problem, a mathematical model of train operation has been developed on locomotive circulation areas, taking into account the daily fluctuations of train traffic, possible deviations in predicting composition formation and other factors. Performing mass calculations for various conditions will allow determining the rational size of the irreducible reserve of locomotives at the stations of its turnover and eliminate the losses associated with the cancellation of the schedule threads due to the lack of provision of finished trains by locomotives. Extensive full-scaled tests were made to determine the difference between actual and planned train traffic, which allowed determining regularities in the formation of planned values of train traffic for use in the simulation model. An algorithm for constructing a simulation model has been developed that provides for the amount of a irreducible reserve of locomotives for different conditions: changing values of the average daily train traffic in the even and odd directions of traffic, traffic incompatibility, the degree of uneven daily traffic, errors in planning (planning quality), etc. The software of the simulation model was developed and its debugging was made to perform mass calculations. The study of the problem of determining the rational size of the irreducible reserve of locomotives at the stations of its turnover was carried out with the support of the Russian Railways and the Russian Foundation for Basic Research. Project No. 17-20-01136.

The possibility of growing crystals with homogeneous impurity distribution over crystal height has been demonstrated in a study of segregation during silicon and germanium growth from thin melt layers using the submerged heater method. Numeric simulation of 200 mm diam. antimony-doped germanium crystallization has shown that, beginning from a 40 mm melt layer thickness, the exact problem solution with convection allowance is identical to the unidimensional heat exchange problem solution in the central ingot part. The conditions under which convection can be ignored in mass transport calculation are more rigorous: the melt layer height must be within 20 mm. In this case Tiller’s ratio can be used for calculating the longitudinal impurity distribution for predominantly diffusion-controlled mass transport pattern. Analysis of the existing attempts to describe the experimental crystal growth results using the simplified formulae shows that they only yield acceptable results if the actual growth rate or change in melt layer thickness during crystallization are taken into account, e.g. as in the formula suggested by Marchenko et al. One can therefore analytically describe the longitudinal impurity distribution in the ingot, e.g. B and P distribution in silicon, and recommend the degree of additional doping of the melt zone under the heater so that to provide a constant impurity concentration over the ingot height. Homogeneous material can be obtained after residual layer solidification in the end portion of the ingot if the growth rate is controlled through varying the cooling rate.

The article contains a method for determining the ma-the permanent way as deflections, angles of section rotation, bending trix of mutual spectral densities of vertical dynamic forces acting on a moments, transverse forces, stresses of its three-layer structures. railway track, depending on its spectrum of irregularities. It will allow to Mathematical model of track oscillations is used for calculations make a more accurate calculation of the mean values and mean-square as a construction containing three infinitely long beams, the lower deviations of vertical dynamic forces, as well as such characteristics of of which lies on the modified Winkler base. Authors present formulas for finding amplitude-frequency characteristics connecting vertical deflections of structural layers and vertical dynamic load acting on a track. A method is described for finding a matrix of mutual spectral densities of vertical dynamic forces acting on a track having real deviations from its position in the profile, with the passage through it of a four-axle freight car. Considered example finds the amplitude-frequency characteristic that connects the vector of dynamic forces in the contacts of wheels and rails with the vector of vertical displacements of wheel centers for the model of a four-axle car. Concluding authors give the results of calculations of the amplitude-frequency characteristic of the elements of the matrix of mutual spectral densities of vertical dynamic forces acting on the track. The received statistical estimations can be used at calculations of service life of ballastless track constructions and loading on roadbed.

A comparative analysis of the indicators of the overall morbidity, mortality and natural increase in the population of the Russian Federation and the Volgograd region for 2012-2015 has been carried out. The results of the assessment of the quality of specialized gastroenterological and cardiological care in the profile departments of II and III level hospitals in the Volgograd region in 2013-2015 have been considered. The indicators of the quality of medical care in the gastroenterological and cardiological departments of the hospitals of the Volgograd region have been analyzed.

We have studied experimentally and theoretically the possibility to obtain a uniform single crystal of SiGe alloy enriched at the Si side. The content of the second component in a crystal 15 mm in diameter and 40 mm in length grown by the modified floating zone technique from the charge of 79.8 at.% Si and 20 at.% Ge composition with 0.2% B admixture has been investigated using selected area X-ray analysis in different points and in line scanning mode along and across the crystal axis. The longitudinal changes in the germanium concentration proved to be well described by the analytical equation previously derived for conditions of Sb (Ga) doped Ge growth from a thin melt layer in the presence of a heater submerged into the melt. For a more accurate description of the experimental data we have made allowance for the change in the melt layer thickness between the growing crystal and the bottom of the submerged heater. The lateral distribution of the second component not exceeding 5% over the crystal diameter can be significantly improved by reducing the curvature of the phase interface during the growth.

For the first time, the multicrystalline silicon is grown via directed crystallization using a heater submerged into the melt. The interaction of the heater casing material with molten silicon is studied on a model heater in the form of a graphite plate coated with a special structure SiC protective layer. During the crystallization, the plate has been kept on the melt surface and has almost completely overlaid the melt mirror, which favored a significant decrease in the rate of gas exchange between the melt and the atmosphere in the furnace. Marangoni convection was not observed in the absence of the free surface of the melt and the crystal was grown on the reduced melt convection, especially at the final stages of crystallization, when the thickness of the melt layer was inferior to the cross size of the crucible. The crystal is established to have a strongly pronounced columnar structure. The measured specific resistance varies over the ingot height from 1 to 1.3 Ω cm, and the lifetime of minority carriers is about 3.7 μs. The carbon and oxygen content in the ingot has been measured via FTIR spectroscopy, and the carbon concentration through the ingot height is shown to strongly differ from the linear dependence typical of directed crystallization.

Conditions have been identified that ensure unseeded growth of bismuth single crystals in air. The axial and radial (directed toward the crucible axis) temperature gradients necessary for the growth process, 40 and 6–7°C/cm, respectively, were produced using the axial-heat-flux-close-to-the-phase-interface (AHP) method. In the preliminary stage of experiments, a single-crystal ingot 40 mm in diameter and 60 mm in length has been obtained. Using a submerged heater that is used in the AHP method, we have developed an experimental procedure for measuring the curvature of the growth front directly in the crystal growth process. The results demonstrate that, for both pure bismuth and a bismuth-antimony alloy, its shape is uniquely determined by the temperature profile along the hot boundary of the melt layer from which the crystal grows. Even at a small superheating, ≃0.5–1.5°C, of the periphery of the submerged heater relative to its center, the growth interface is convex toward the melt during growth.

A crystal growth unit has been designed for Cd1 − xZnxTe growth by the axial-heat-flux-close-to-the-phase-interface (AHP) method at argon overpressures of up to 12 MPa. The influence of melt superheating, growth rate, melt layer thickness, argon pressure, and growth mode on the Zn distribution in 21- to 45-mm-diameter crystals and defect formation in Cd1 − xZnx Te ingots has been investigated. The results demonstrate that the AHP method offers the possibility of effectively controlling the shape of the solid-liquid interface and ensures low fluid velocity and high radial compositional homogeneity. The feeding method used markedly improves the axial Zn profile and ensures low dislocation density (5 × 103 cm−2) in the grown crystal.

A mathematical model is presented that describes interactions between Bt-crops and insect pests taking into account the plant growth rate, consumption of plant biomass by pests, suppression of insect proliferation by Bt toxins, emergence of Bt-resistant insects and their mixing with the wild type. It is shown that migration of Bt-susceptible insects from “refuge plots” onto the Bt-crop field invaded by resistance-carrying insects improves the yield dynamics; being high enough, this inflow eventually eliminates the resistant pest population.

Simulation of some consequences of invasion of a Bt-resistant insect pest into an agricultural eco-system containing a Bt crop shows that such invasion alters the plant biomass dynamics, decreases the crop yield, and impairs yield predictability. The yield is poorly predictable in a small region of parameter values, which depends on the duration of the insect reproductive period relative to the crop-growing season.

A conceptual mathematical model of the dynamics of fish and zooplankton (rotifer) populations of connected lakes Naroch and Myastro (Belarus) is built and examined with parameters based on field data. It is shown that community coupling and trophic interactions give rise to both regular and irregular oscillations in population numbers.

The present work describes the results of spectral absorptivity, α, and thermal conductivity, λ, studies for compound oxides Bi4Ge3O12, Bi12GeO20, Bi4Si3O12, and Bi12SiO20 in molten and monocrystalline states. The data for the spectral absorptivity were obtained by placing the sample onto a mirror and using the transmission method. To obtain the data on the thermal conductivity of crystals, the stationary method of two identical samples was used. The data for the thermal conductivity of melts were obtained by a new stationary relative method in which the thermal conductivity of the crystal is used as a reference. Special attention is focused on numerical and experimental error analysis at high temperature. The studies have shown that α in the range of a transmission band strongly depends on crystal purity. It varies from 0.0005 cm−1 to 0.03 cm−1 for Bi4Ge3O12 and reaches 0.15 cm−1 for Bi4Si3O12. It was found that α is significantly greater for melts than for crystals, reaching (150 to 200) cm−1 for the Bi4Ge3O12 melt. The thermal conductivity of the melts under investigation was found to be much smaller than that of the corresponding crystals.

CsI〈Tl〉 crystals have been grown by the axial-heat-flux-close-to-the-phase-interface (AHP) method in a purpose-designed apparatus at an argon overpressure. The furnace and crystallizer of the apparatus have been designed to ensure considerable (5 to 100 K/cm) axial and low (within 1 K/cm) radial temperature gradients at the growth interface. The effects of the melt layer thickness, temperature gradient, and activator concentration in the melt on the crystal quality have been studied. The results demonstrate that reducing the AHP heater temperature for even a short time (by 2°C in 3 min) markedly raises the actual growth rate, from 2 to 15 mm/h, and leads to entrapment of bubbles of various diameters and TlI inclusions.

An antimony-doped germanium single crystals were grown by the axial heat processing (AHP) method for experimental–numerical research of faceting of melt/crystal interface. The comparing of experimental and numerical results has shown the high accuracy of determination of heat and mass transfer during faceted Ge AHP crystal growth at using of the novel model of facet growth. The conditions were found to conduct an experiment on influence of melt flow direction on facet Ge morphological instability.

An antimony-doped germanium single crystal was grown by the Axial Heat Processing (AHP) method from the melt to study the influence of facets on the morphological stability of a solid/liquid interface. It is shown that the faceted portion of the interface remains more stable than the non-faceted portion. In addition, instability of the faceted region occurs at a higher solute concentration with larger cell spacing. A mathematical model, accounting for the presence of facet, predicted the solute profile and morphological features of the grown crystal are in good agreement with the experimental data.

To investigate a weak melt flow effect on the segregation process, the axial heat processing crystal growth technique was used at conditions of low-frequency temperature fluctuations. This technique was applied to Te-doped GaSb crystal growth. A two-dimensional transient numerical model based on the “KARMA1” computer code was developed to investigate fluid flow, solid/liquid interface shape and dopant concentration in the grown crystal. The model incorporated real boundary conditions measured during the experiment. The predicted evolution of the solid/liquid interface shape and the concentration distribution agreed well with the experiment, including the formation of growth striations. This gave the possibility to determine conditions of dopant striation appearance.

Combined experimental and numerical tools are used to analyze the effect of convective and radiative heat transport, faceting phenomena, and the optical thickness of the Bi4Ge3O12 (BGO) crystal on the measurement and calculation of melt/crystal interface kinetics during the axial heat flux close to the phase interface growth of BGO single crystals. Results show that, in the general case, accurate determination of growth kinetic relations requires the application of models which account for all of the above phenomena (radiative and convective heat transport, faceting phenomena, etc.). Failure to take these into account may result not only in quantitative errors, but also even in qualitatively wrong determination of interfacial kinetic mechanisms.

Thermal conductivity and spectral absorption coefficient of bismuth germanate Bi 4 Ge 3 O 12 are measured in crystalline state and in melt within temperature range 750–1350 K. It is discovered that thermal conductivity of the melt is low and close to those of thermal insulation (0.2 W/m K). Thermal conductivity of the crystal at melting point is not high; it is equal to 1.15 W/m K. It is stated that the single crystal is transparent till melting point while melt is practically opaque for thermal radiation. Due to these features of the Bi 4 Ge 3 O 12 melt and crystal, heat transfer mechanism in the liquid phase drastically differs from that in solid.

An antimony-doped germanium single crystal was grown by the axial heat processing (AHP) method from the melt to study the influence of facets on the morphological stability of a solid/liquid interface. A mathematical model together with experimental data was utilized to predict the solute concentration and stability in the grown crystal. It is shown that the faceted portion of the interface remains stable longer than does the nonfaceted portion. In addition, instability of the faceted region occurs at a higher solute concentration with larger cell spacing.

The influence of the absorption coefficient a of a growing crystal on the accuracy of determination of supercooling AT at the crystal-melt interface has been studied. The value of ΔT is determined from the brightness temperature Tb of the interface measured by an optical pyrometer through the crystal. It is shown that the absorption coefficient a, the temperature gradient, and the length of the crystal influence the value of T b . Conditions of measurement ensuring an error of AT determination less than 0.1 K are reported. Numerical calculations and experimental techniques are proposed for data correction in the case when in situ measurements are carried out under the effect of a on supercooling.

Methods of measuring the thermal conductivity of materials in solid and liquid state at high temperatures are reviewed. Factors influencing the accuracy of the obtained results are examined. Special attention is paid to the role of contact resistance. Results for the thermal conductivity of sodium chloride, bismuth germanate, and germanium over a wide temperature range are presented. The behaviour of thermal conductivity during melting of these materials is analysed.

The possibility of obtainingthe well-known weakly forced melt flow alongthe melt–crystal interface is studied. It is shown that the well-known laminar-forced melt flow can be provided duringcrystallization by a method of crystal growth in an axial heat flux close to the phase interface (AHP method). The calculations of the 2D transient problem of crystal growth by the AHP method under microgravity conditions showed that axial microaccelerations with amplitude less than 10 � 3 g and a frequency of more than 0.01 Hz will have no influence on this flow. r 2002 Elsevier Science B.V.

The determination of the dependence for supercooling of Bi 4 Ge 3 O 12 facet on growth rate V is discussed. The method of measurement of the interface temperature by an optical pyrometer in the presence of several facets with different crystallographic orientation at the measuring spot is examined.

The results of in situ measurements of dependence of growth rate on supercooling of the Bi 4 Ge 3 O 12 (BGO) interface are presented. Supercooling was measured with an optical pyrometer through the growing crystal. The features of interfacial kinetics for (211) and (110) facets are described. The correlation between results of characterization and data on supercooling, and morphology of the interface is analyzed.

In this work we made a first attempt to grow Si1−xGex single crystals by the so called modified float zone technique [1] , without contact of container walls, using a modified AHP (axial heat flux close to the phase interface) heater. This method was derived from the “modified Bridgman” technique using a submerged heater [2] . Some advantages of this method are the improvement in crystal quality [3] , [4] , the reduction of the radial temperature gradient and with it the reduced radial segregation during the growth experiment. For comparison another Si1−xGex crystal was grown by the conventional float zone method, using a residual spark plasma sintered feed rod from the initially described growth experiment. Spark plasma sintering is a synthesis and consolidation technique using a pulsed current and an axial pressure to activate the sintering process [5] . Both samples were characterized by EDX, ICM, Raman and Photoluminescence spectroscopy for the purpose of analyzing the crystal quality. The use of spark plasma sintered raw material as feed material was investigated.

Results of experimental research on the thermal conductivity for sodium chloride melt are described. Analysis of these data and data obtained by other authors is given. The mean value calculated from data of different studies is 0.41 W m -1 K -1 . The overall accuracy of this value is estimated to be ±7%. The influence of the experimental conditions on optical properties of the melt is considered. It is recommended to use the NaCl melt as a reference for measurements of the thermal conductivity of semitransparent melts.

The results of in situ measurements of supercooling of the interface during the growth of Bi 4 Ge 3 O 12 single crystal from melt are presented. Supercooling was determined by measuring the intensity of intrinsic thermal radiation from the interface, which was recorded with an optical pyrometer through the growing crystal. The dependence of growth rate on supercooling was determined from the experimental data on supercooling versus the cooling rate for a thin layer of melt. The features of the determination of supercooling during the formation of macrosteps on the facet are considered. Experimental data are obtained concerning the dependence of growth rate on supercooling for crystal growth in the [2 1 1] direction. ( 2000 Elsevier Science B.V. All rights reserved.

A brief description and analysis of methods concerning the determination of the dependence of interface supercooling on the growth rate during Bi 4 Ge 3 O 12 single crystal growth from the melt are given. The supercooling measurement is based on determination of the thermal radiation intensity of the interface by an optical pyrometer through the growing crystal. Research was carried out during crystal growth in the direction [211]. A high value of supercooling and nonlinear character of its growth rate dependence have been found. The role of some sources of systematic errors in the supercooling measurements is discussed.

The application of the crucibleless method for the growth of dielectric crystals from the melt is studied. This method is a variant of crystal growth in an axial heat flux close to the phase interface (AHP method). A special AHP-heater placed in the melt close to the growing crystal allowed the creation of a planar interface over practically the whole cross section. This scheme gave an opportunity to control the temperature gradient in the melt close to the interface over a wide range (from 10 up to 200 K/cm). Problems of crystal growth: holding of the melt layer with the required thickness by surface tension forces; supply of charge to the AHP-heater and feeding melt to the growing crystal; adjustment of crystallizer are considered. The conditions of morphological instability of the interface are found for LBO crystal. It was determined that crystallographic direction of facets bounding the cells is the same as those forming the crystal habitus.

A mathematical model is presented, which describes interactions between Bt-plants and pests in terms of the plant growth rate, plant annual reseeding, consumption of plant biomass by pests, the action of Bt toxins, and the emergence of Bt-resistant insects. It has been shown that the migration of Bt-susceptible insects affects the Bt-crop yield dynamics and provides the exclusion of Bt-resistant pests if the migration exceeds the threshold value.

The results of determination of the supercooling dependence at the interphase boundary on the rate of growth from melt of the monocrystal Bi4Ge3O12 in the [211] direction are presented. Determination of supercooling was based on optical pyrometer measurements of the intensity of heat emission from the interphase boundary through the growing crystal. The crystal was grown by the AHF method (axial heat flux near the front of crystallization) by cooling the AHF heater at a specified rate. The growth rate corresponding to the measured supercooling value was determined by calculations. The study has shown that the supercooling is high and varies nonlinearly with the growth rate.

The results of simulations of some consequences of the invasion of Bt-resistant pests into an agricultural ecosystem containing a Bt crop are presented. It is shown that the invasion of Bt-resistant pests leads to changes in the plant biomass dynamics, a decrease in the Bt crop production, and the deterioration of the predictability of the Bt crop production. We show that the parameter values at which the badly predictable Bt crop production takes place, occupy a minor area in the model parameter space. The size of the area depends on the insect reproduction period and the duration of the growing season.

A conceptual mathematical model of fish and zooplankton (rotifer) populations inhabiting the lakes Naroch and Myastro has been developed and studied. The parametrization of the model was carried out having regard to the field observation data. The population dynamics was simulated taking into account that the lakes Naroch and Myastro are coupled with each other by a channel. It was shown that both the population coupling and trophic interactions result in regular and irregular oscillations of the population size.

We present a mathematical model of the dynamics of a spatially heterogeneous predator-prey population system. A prototype of the model system is the Syamozero lake fish community. We study the impact of the invader, an intermediate predator, on the dynamics of the fish community. We show that the invasion can lead to the appearance of chaotic oscillations in the population density. We show also that different dynamical regimes resulting from the invasion, i.e., stationary, non-chaotic oscillatory and chaotic ones, can coexist. The "choice" of a specific regime therewith depends on the initial invader density. Our analysis of solutions of the mathematical models shows that the successful invasion of the alien species takes place solely in the absence of the competition between the invaders and the native species.

We have developed a conceptual mathematical model of the dynamics of a spatially heterogeneous population system, the prototype of which is the Syamozero lake fish community. Based on the analysis of solutions of the model, we show that interrelations between prey and predator populations in two neighboring habitats (pelagic and offshore zones) can lead to both undamped oscillations and stationary values of the population size. The population density was found to be close to the values oblained in the course of long-term observations of the biota of the Syamozero lake. Besides, we showed that the transition to the stationary states can be accompanied by long-term (dozens and hundreds of years) damped oscillations of the prey and predator population size. In natural waters, long-term transition periods can prevent the attainment of stationary regimes of fish community functioning.

We present the results of mathematical modeling of a rotifer species inhabiting two coupled habitats with different environmental conditions. We use the modified Consensus model and show that the exchange between the habitats can lead to chaotization of originally regular plankton dynamics and synchronization of plankton biomass oscillations. As a result, the invasion of a chaotic regime takes place.

An additional heater, similar to the axial heating process setup (AHP heater), was used in crystal growth of Si and its compound with 20% at Ge by the Floating Zone (FZ) method with the purpose of controlling both the shape of the melt–crystal interface and the thermal conditions at the interfaces during the run. The heater shapes the melt zone around itself by surface tension forces, being suspended between the growing crystal and feed rod. To protect the graphite casing of the heater against the aggressive action of molten silicon, the casing surface was coated with SiC having a special nano-crystalline structure. The range of the melt layer thickness, which one could establish as high as possible for the stability of the shaping process, was found to be up to 20 mm. Grown As- doped Si single crystals with a diameter of up to 15 mm was shown to have strong twinning directly caused by presence of the SiC inclusions revealed in the bulk of a crystal. The possibility of reducing the convexity and produce an interface close to a flat shape by means of the AHP heater was proved. Faceted growth of Si was found to be present in crystal growth on [111]-oriented seeds, with the faceted area occupying almost all of the cross section of the crystal under certain conditions.