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This paper studies the influence of lattice and shell type architecture on the mechanical properties of biodegradable polymer scaffolds (cellular matrices) designed to create structures for bone tissue engineering. Varying the topology of nodal connections makes it possible to control the relative rigidity of the metamaterial in the range from 0.004 to 0.123. It is shown to be possible to create permeable scaffolds using thermally extruded 3D printing based on polymers of different elasticities—polylactide and polyurethane. The use of “unit cells” of various types allows fabricating structures such as shells based on polylactide with a compressive strength of 1.5 to 19.7 MPa. Shells with a cubic type architecture based on polyurethane can be almost reversibly deformed at values of deformation of more than 50%. The developed approaches for obtaining polymer metamaterials and modifying their surface with calcium phosphate layer using an artificial interstitial fluid can increase the hydrophilicity of materials.

The article presents studies carried out on a group of rats in order to determine the influence of the morphological characteristics of animals on the conduct of general inhalation anesthesia. It was found that if the rules for the preparation of animals, dosage of drugs (due to the physiological characteristics of rats), as well as proper care of animals after anesthesia are observed, the risk of complications, up to death, is reduced to a minimum.

The effect of atorvastatin on the immune system and lipid metabolism after 24-week treatment of patients with chronic myocarditis is considered. Statins have been found to improve the clinical course of heart failure with a preserved ejection fraction in patients with myocarditis: they reduce the functional class of heart failure, improve the systolic function of the heart and its arrhythmogenic potential. Despite the large amount of conflicting data in the field of statin use in heart failure, one can think about the possible influence of molecular differences in statins on their pharmacological and pleiotropic effects. In particular, atorvastatin, which has lipophilic properties, is able to penetrate cardiomyocytes in contrast to hydrophilic rosuvastatin, which may partially explain the positive cardiac effects of atorvastatin in patients with heart failure with a preserved ejection fraction. The probable basis for the positive effect of atorvastatin on morphofunctional parameters in heart failure is its positive pleiotropic effects associated with a decrease in рro-inflammatory immune markers and subsequent leveling of negative neurohumoral activation. An additional mechanism that caused the positive effect of atorvastatin on the clinical course of heart failure can be considered a factor of preservation of systolic function of the left ventricle.

Technologies for the 3D printing of metallic powders are being increasingly extensively used around the world as alternatives to casting and machining to manufacture components of complex shapes and prototypes. Silicon-alloyed aluminum alloys are the most widely used materials in the selective laser melting technologies, which is caused by the price of these alloys and their high manufacturability for the layer-by-layer fused deposition, owing to their low susceptibility to hot cracking under thermal and shrinkage stresses. High rates of cooling the melt facilitate the formation in the material of ultradispersed silicon-containing phases, which results in increased strength. In the article, exemplified by two cast alloys (AK7ch and AK9ch), the speeds of the process of building up the products by the selective laser melting technology have been determined at a laser-beam power of 300 and 325 W and an energy density within the range 89–32 J/mm3. It is shown that, for the AK9ch alloy, lower porosity values are achieved within the investigated energy density range when compared with the AK7ch alloy and better mechanical properties of the alloy with a higher silicon content are achieved within the range of lower laser-beam energy densities than for the alloy with a lower silicon content. The mechanical properties of the materials produced under the optimal selective laser melting conditions comply with the most stringent requirements for the mechanical characteristics of the castings of the AK7ch alloy upon heat treatment.

Mining of a horizontal isolated seam in a uniform medium in plane strain conditions is considered. The stress distribution in roof rocks of the coal seam is obtained at different stages of mined-out area development. The stresses are governed by the complex-variable function, which allows determining location and configuration of zones of stress relaxation and additional load in rock mass. This information is required for estimation of induced jointing and formation of gas pockets in the coal seam parting. The use of the analytical solution makes it possible to obtain relations for finding stress concentration factors and to present the related parameters as contour lines.

The article presents the results of questionnaire survey of physicians concerning issues of prevention and dispensary observation of а-HCV/HBsAg positive patients. The study established inadequate awareness and medical activity of physicians concerning issues of prevention and dispensary observation of patients from risk group and patients with viral hepatitis C/B. The working experience and medical length of service without any additional training give no guarantees of sufficient knowledge in issues of prevention, timely detection and corresponding observation of a-HCV/HBsAg positive patients.

Clinical following-up of children born to a-HCV/HBSAg-positive women referred to a risk group for vertical transmission of hepatitis C/B viruses is one of the most important areas of medical care for this group of patients. The data of the analysis of the organization, quality and effectiveness of dispensary observation of children from the «risk groups» for the vertical transmission of HCV/HBV infection are presented. The unsatisfactory quality and effectiveness of the dispensary observation of this category of patients has been established. Inadequate medical activity and awareness of doctors on the prevention of parenteral viral hepatitis have been identified. There is substantiated the necessity of implementing a multi-level system for the prophylaxis of viral hepatitis C/B in a system encompassing both a child and a mother based on continuity at each of its stages, which will allow reduce the number of infected children of younger age groups.

Introduction. The incidence of chronic viral hepatitis C in women is determine the relevance of the infection vertical transmission to children with the outcome to chronic viral hepatitis C. It is necessary to assess the effectiveness of current measures to prevent perinatal viral hepatitis C and to develop strategy for prevention viral hepatitis C in children for future. Aim: to evaluate the organization and putting into effect the prevent of perinatal viral hepatitis C in an outpatient setting. Material and methods: authors presents the results of questionnaire survey of а-HCV-positive children’s mothers with chronic perinatal viral hepatitis C. The analysis of the results was carried out using Cohen Kappa method, Cohen Kappa consent coefficient (κ) was calculated. Results: The study established inadequate organization and implementation of measures to provide medical care for the prevention of perinatal viral hepatitis C int all stages of ambulatore care. Conclusion: it is necessary to create a multi-level system of prevention of viral hepatitis C in children.

Objective: to study the basic characteristics of changes revealed by MRI in patients with syringomyelia associated arachnopathy before and after surgery.Materials and methods. MRI was performed in 58 pat ients with syringomyelia before and after surgery in period from 2013 to 2016.Results.The diagnosis “syringomyelia” was approved in 41 patients. There was huge regression (more than 50% of volume) of syringomyelia cavity in 17 (41.4%) patients. In 20 (48.7%) patients marked decrease in size syringomyelia cavity (less than 50%), the volume expansion of the front and rear of cerebrospinal fluid spaces.Conclusions. The use of modern MRI Protocol in various types of syringomyelia allows not only to detect and give a comprehensive feature cavities, but also to detect adhesions, location and length, as well as to assess the dynamics of the disease after surgical treatment.

A comparative analysis of methods for calculating digital holograms based on discrete transformations for various types of objects is presented. Qualitative results of synthesis and reconstruction of holograms are obtained, as well as examples of the realization of some of the types of holograms considered. The quality of digital hologram recovery is estimated by calculation of signal-tonoise ratio (SNR) and root-mean-square error (RMSE).

This paper is a review on implementation of measuring systems for two-phase helium, hydrogen, liquefied natural gas (LNG), and oil-formation/salty water flows. Two types of such systems are presented. The first type is based on two-phase flow-meters combining void fraction radio-frequency (RF) sensors and narrowing devices. They can be applied for superconducting accelerators cooled with two-phase helium, refueling hydrogen system for space ships and some applications in oil production industry. The second one is based on combination of a gamma-densitometer and a narrowing device. These systems can be used to monitor large two-phase LNG and oil-formation water flows. An electronics system based on a modular industrial computer is described as well. The metrological characteristics for different flow-meters are presented and the obtained results are discussed. It is also shown that the experience gained allows separationless flow-meter for three-phase oil-gas-formation water flows to be produced.

Technological solutions based onthe integrated approach are presented, which optimize the manufacturing process and satisfy the requirements imposed on spherical rotors of electrostatic gyros. System modelingis used to study the main stages of defining the rotor functional parameters and to constructa system of models that determines the coordinated processes of diffusion welding, precision sphere lapping and rotor weight correction. The practical results of rotor manufacturing and the prospects for accuracy enhancing are provided.

The paper presents the results of studies of the impact of operating time of single-bucket excavators on their operational performance. The results of production experiments made it possible to establish the dependence of the pressure change in the hydraulic system of the excavator during the process of cutting soil on the operating time. This parameter characterizes the variation value of the cutting resistance of soil at the cutting edge of a bucket, the duration of operation cycle and its operational productive capacity. Based on the results of the study, a technique has been developed that permits to determine economically feasible periods of effective operation of excavators, as well as to establish the optimal technological parameters for cutting soil: the thickness of the soil shavings and speed of its cutting by an excavator.

The analytical review covers the key factors that influence permeability of a coalbed under mining-induced alteration of stress state. The authors put forward an analytical relation between coal permeability, stresses and adsorbed gas to define parameters of gas leakage zone parameters and laws of mass transfer. The analytically derived relation is compared with the known model of coal structure and with the experimental results. The proposed model of coalbed permeability allows mechanism of leakage and localization of seepage zones in coal provided that the model parameters are properly selected or found experimentally.

In article are described the aspects of prophilaxis, diagnostics and treatment, the clinical manifestations of various species of metabolic and energy disorders, wich more frequently have the alimentary origin, united by the term «starvation illness». «Starvation illness» is the nosological complex, actual for Navy, which meets in time of peace and a war, at development of emergency situations and accidents at the sea. All stages of alimentary dystrophy, hypo- and avitaminosis С, А, В1, В2, В 6 , РР are described. The materials of article were included into the new textbook on naval therapy published in Russian Military Medical Academy in 2015.

Stomach cancer is a leader in the structure of cancer pathology in Ukraine and in the world. This paper summarizes own results and literature data on diagnosis, treatment and prevention of stomach cancer. Authors analyzed the experience and specific features of long-term treatment and diagnostic approach to patients with stomach cancer involving esophagus. Conducting pre-and postoperative cytostatic herbal therapy and cryosurgical operations during surgical treatment in patients with spread of tumor process allows to statistically significantly improve 3-and 5- year survival of patients.

The influence of integral electrical characteristics (current, voltage, power) and differential characteristics (the resistance of the batch, arc, and melt) on the power consumption, manganese extraction, and productivity during ferrosilicomanganese production in superpowerful electrofurnaces is investigated.

The article represents the review of issues of self-monitoring of blood glucose (SMBG) in diabetes treatment. The therapeutic purposes are considered when carrying out SMBG before and after the meals, accepted in Russia, providing an individualization depending on age, existence of severe complications and the risk of hypoglycemia. SMBG frequency is presented at various options of the antidiabetic therapy. The value of carrying out SMBG for the patient and the doctor is discussed. The principles of the work photometric and electrochemical glucometers are given. Issues of accuracy of blood glucose measuring accepted by the International organization for standardization for the systems of SMBG are presented. The reasons of errors to the system evaluation of blood glucose are connected with incorrect hand washing, improper coding of test strips, external conditions (altitude, temperature, humidity), hematocrit, acidosis, hyperlipidemia, concentration of oxygen in blood, exogenous interfering substances (some medicines). The structure and rules of maintaining the diary as the main way of the storage of results of SMBG are presented. Data of the international and Russian studies on an assessment of efficiency of SMBG are shown. The SMBG new methods are discussed in the section on continuous glucose monitoring.

The generation mechanism of microwave radiation in the system with azimuthally-periodical current of an electron beam that excites a high-Q quasi-optical dielectric resonator was developed. Eigen parameters of a cylindrical Teflon resonator were determined. Radiation was locked in the investigated system by a detector of 8-mm wave band. Design philosophy of microwave oscillators with high-Q resonators, in which electromagnetic “whispering gallery” modes are excited by electron beam, was developed.

It is found that, when the shape of a dielectric sphere (hemisphere) operating under the whispering gallery mode conditions is perturbed by a surface curvature gradient (ellipticity), the unloaded Q factor of the sphere degrades and its resonance frequencies change. It is shown theoretically and experimentally that an elliptic irregularity removes frequency degeneracy of whispering gallery modes at millimeter waves.

The technique for determination of dielectric parameters of substances is submitted on a base of using a high-Q “whispering gallery” oscillations in a quasi-optical spherical resonator. The function ability of a method is shown on an example of measurement of permittivity for several substances in the 8 mm wave band.

The anisotropy of parameters is an intrinsic characteristic feature of dielectrics employed in production of high-Q resonators. A theory of azimuthal-homogeneous resonant oscillations in a single-crystal sphere is developed. It is demonstrated that the anisotropy gives rise to TM oscillations of two orders at different frequencies. Oscillations with large polar indices are numerically investigated.

A semicylindrical dielectric resonator with a thin cylindrical inhomogeneity in the region of the field antinode of a whispering gallery eigenmode has been studied. Characteristic equations determining the complex eigenfrequencies of such resonators with axially homogeneous eigenmodes are obtained. It is shown that the presence of a dielectric or conducting inhomogeneity leads to a frequency shift and causes additional energy losses of the eigenmode.

The influence of a ring layer filled with various substances on the eigenfrequency and Q-factor of a cylindrical quasi-optical dielectric (Teflon) resonator has been investigated. The spectral and energy characteristics of an axially homogeneous whispering gallery eigenmode of this resonator are analyzed for the first time as dependent on the radius and thickness of the ring layer. It is established that the eigenfrequency behaves differently when the ring layer is filled with liquids characterized by large and small losses.

A rigorous theory of the propagation of electromagnetic waves in round anisotropic and semiconductor rods in the presence of an arbitrarily directed anisotropy axis or external magnetic field is developed. New types of independent waves are discovered. Exact dispersion equations are obtained for them, which define the dependence of their spectral characteristics on the parameters of the semiconductor or anisotropic crystal and on the magnitude and direction of the constant external magnetic field. The results of numerical investigations for rods made from a semiconductor or a uniaxial crystal are presented.

A diagnostic microprocessor device for checking the generator water-cooled stator winding insulation, realizing semiautomatic measuring of the level of resistance and absorption coefficient of the stator winding insulation, in which case the shunting effect of the water hoses is eliminated, was developed and is operating successfully.

Natural oscillations of radially three-layered dielectric resonators have been investigated. The latter have the form of a sphere and cylinder limited by ideally conducting end planes. The expressions for components of electromagnetic fields of natural oscillations and characteristic equations of resonators were obtained. Numerical investigations of resonators were carried out in the 8-millimeter wavelength band. The impact of the middle layer parameters of resonators on their spectral and power characteristics was also analyzed. It was proposed to use such resonators for extracting the complex dielectric permittivity of substances.

Results are presented of theoretical and experimental investigations of whispering-gallery oscillations in a shielded isotropic layered spherical dielectric cavity. Oscillations whose Q factor is two orders of magnitude higher than that of the oscillations of an open dielectric sphere are studied. Intermode interaction is observed between various cavity oscillation modes.

Large quantity of cryogenic temperature sensors will be used for operation of the International Linear Collider (ILC). Most of them will be subject to high radiation doses during the accelerator lifetime. Understanding of particle energy spectra, accumulated radiation dose in thermometers and its impact on performance are vital in establishing technical specification of cryogenic thermometry for the ILC. Realistic MARS15 computer simulations were performed to understand the ILC radiation environment. Simulation results were used to establish radiation dose requirements for commercially available cryogenic thermometers. Two types of thermometers, Cernox® and TVO, were calibrated prior to irradiation using different technique. The sensors were subjected then to up to 200 kGy electron beam irradiation with kinetic energy of 5 MeV, a representative of the situation at the ILC operation. A post-irradiation behavior of the sensors was studied. The paper describes the MARS15 model, simulation results, cryogenic ...

Eigen oscillations of a radially three-layer cylindrical dielectric resonator bounded with two perfectly conducting end surfaces are studied. The characteristic equation for the anisotropic resonator buried into anisotropic medium is obtained. The numerical investigations of the resonator with internal and external layers made of Teflon and middle layer filled with transformer oil or distilled water are carried out. Spectral and energy characteristics of resonator for different thicknesses and positions of middle layer are represented.

The characteristic equation for complex frequencies of layered dielectric resonator was obtained. The eigenfrequencies and Q-factors depending on diameter of inner layer at the presence of different substances are presented. The numerical investigations of whispering gallery modes of QDR are performed. The possibility of using such type of resonator as measuring cell for substances having both large and small losses is presented in this paper

The dispersion equation for complex frequencies of a radially-three-layer cylindrical dielectric resonator with perfect conductive end walls was obtained. The studying of influence of a middle layer, filled different substances, on a frequency and quality factor of resonator was carried out. Spectral and energy characteristics of a resonator with a whispering gallery oscillation were studied at different thickness of middle layer and its position along the radius. Different nature of behavior of an eigen frequency of resonator was obtained filling a middle layer by liquid with both small and large losses.

Temperature dependences of characteristics of a capillary-waveguide resonance are studied for strongly absorbing mediums. A possibility of using of a method for measurement their frequency dependences is surveyed. Temperature influence on frequency and Q-factor and energy absorption of electromagnetic field is researched at the resonance.

Publisher Summary This chapter presents a temperature monitor to measure cryogenic temperatures by means of resistive temperature sensors. This is a box of 172 × 76 × 24 mm3 connected to COM-port (RS232) of a personal computer. A four-lead technique is used to measure the resistance of the temperature sensor with respect to the precision reference resistor. The main characteristics are: the number of measured channels/sensors can be from 1 up to 15 or 16; the range of measuring direct current is from 0.5 μA to 5 mA; the range of measured resistances, R, is from 1 Ohm to 100 kOhm; the accuracy of measurements is ∆R/R

The capability of mechanical frequency tuning of Gunn diode self-oscillator by the both metal and dielectric pin inserted into the partially shielded quasi-optical dielectric resonator is considered. The resonator's eigen frequencies obtained theoretically and experimentally are compared with oscillation frequencies

The influence of defects in spherical forms of semispherical dielectric resonators (DRs) on their oscillation frequency, Q-factor and field distribution has been studied in the present paper. It is shown that even minor deviations (/spl sim/1%) in spherical forms affect the resonator EM characteristics. The frequency splitting and dependence of spectrum parameters on the azimuth angle in semispherical dielectric resonators with small deviation in spherical forms has been observed experimentally.

The report continues our investigations of the thermometers which can be operated under conditions combining high radiation environment and cryogenic temperatures. To clarify temperature shifts due to fast neutron irradiation up to 10 16 n/cm 2 , additional platinum, carbon-glass and TVO temperature sensors were tested. The selected sensors were preliminary calibrated, and a series of experiments were carried out with irradiation of the sensors at 77.3 K and 293 K when their readings were measured in-situ. The post-radiation behavior of the sensors was estimated as well. The obtained results are discussed.

The resonant modes, which are excited at the shielded dielectric hemisphere, are investigated by the theoretical and experimental methods. The low-Q-factor modes of air cavity and high-Q-factor whispering gallery modes of dielectric structure are existed together in the case of high radial index value. The Q-factor value of the whispering gallery modes of the shielded dielectric sphere with the certain correlation between the sizes of dielectric hemisphere and metal shield can be more great than the Q-factor of the whispering gallery modes of the similar open dielectric resonator.

Publisher Summary This chapter helps in designing, building and testing a system for experiments with the 1.3 GHz superconducting cavity. The major part of the system is a horizontal cryostat which includes a helium vessel for the cavity, He-gas and LN2-cooled shields, two nodes for RF couplers, a device for mechanical stretching or squeezing the cavity and a control system. Cooling down to 2.0 K and below is performed with saturated superfluid helium pumped by 500 1/s unit. Operation experience collected up to date is discussed in the chapter. The feature of the control system is the usage of 16 channels cold multiplexer to measure temperatures within the liquid helium vessel. Its components are tested for the radiation environment performance. The obtained results are presented for the various dose values. In the environment combining gamma and neutron radiations and cryogenic temperatures, up to the total doses of approximately 10,000 Gy and 3·l013n/cm2, correspondingly, the cold multiplexer based on the HCMOS PC74HC/4067 chips, can be used successfully. To define these boundaries more exactly, further explorations are needed.

We have studied the influence of finite dimensions of the end screens on the spectrum of whispering gallery modes in a teflon cylindrical quasioptical resonator. The dependence of the resonance oscillation frequency on the radius of conducting end screens is determined for the first time. Variation of the screen radius leads to transformation of the axial index of HE modes.

The paper presents the methods of optimizing the transducers designed for measurements of the void fraction of two-phase flows in the channels of round and annular cross section. On the basis of the analysis performed concrete solution of relatively high technical characteristics is proposed. Rated and actual characteristics of signal ranges and measurement errors are given for both sensors. Influence of the mass velocity on the void fraction of adiabatic two-phase flows is theoretically analysed. Effects of friction and of liquid-into-vapour entrainment are shown. Calculation results are compared with the obtained experimental data for helium. Special attention is given to the specific features of the processes in channels with different cross section.

This article presents results of investigations of the cryogenic thermometers which can operate under high radiation environment. To clarify the temperature shifts due to gamma irradiation up to 1 MGy, the platinum (two types), carbon-glass, and TVO temperature sensors have been tested. Before the irradiation run, the selected sensors were calibrated and a series of experiments was carried out under irradiation of the sensors at 77.3 and 293 K when their readings were taken in situ. Afterwards, the postirradiation evolution (short and long time) of the sensors was measured at 4.2, 77.3, and 293 K. The results, depending on the type of the sensor, can be optimistic or pessimistic. Some comparisons with analogous data for fast neutron treatment have also been made.