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The use of mesenchymal stem cells (MSCs), which have a pronounced immunomodulatory activity, is a promising direction in the development of biomedical cell preparations (BMCPs). In oncohematology, the use of BMCPs containing MSCs is aimed at supporting hematopoiesis during cotransplantation with hematopoietic stem cells (HSCs) and suppressing immune conflicts during allogeneic unrelated transplantation and severe autoimmune processes. An obligatory stage of registration of BMCPs is confirmation of the identity of the MSC cell line (CL), which includes the establishment of morphological characteristics, evaluation of the expression of specific markers and proteins, and confirmation of the genetic stability of CL during cultivation. Determination of markers of genetic stability is possible using various methods, however, according to the recommendations of the American National Standardization Institute, the standard is the analysis of short tandem repeats (STR analysis). The purpose of the study is to develop an algorithm for determining the authenticity of BMCPs containing MSCs, including STR analysis. Material and methods. Identification of MSC cells in BMCP was performed according to the criteria of the International Society for Cell Therapy. Viable cells were counted in a Goryaev chamber. Immunophenotypic characteristics of MSCs were determined by flow cytometry. The level of production of specific proteins was assessed using enzyme immunoassay. Genetic stability markers were identified by STR analysis. Results and discussion. The methods were tested in triplicate for ten BMCP samples to confirm the reproducibility and reliability of the results. The developed algorithm for determining the authenticity of BMCP has a high accuracy, as it includes the STR analysis technique, which makes it possible to identify 19 polymorphic STR markers located on different alleles. Using the method will allow BMCP manufacturers to go through the procedure of state registration of drugs.

This paper presents the methodology and results of optimization of the waste heat recovery system (WHRS) of a mobile compressor unit (MCU) designed to compress natural gas using a computer model in the MatLab with the CoolProp thermodynamic package. In the course of the study, a computer model of the WHRS is built, a criterion for the efficiency of recuperation is determined, an optimization problem is formulated and its solution is carried out. The boiling pressure and mass flow rate of the working fluid in the Rankine cycle are taken as the optimization parameters. With the optimal values of these parameters, the smallest value of the relative mass fuel consumption of the MCU is achieved, that is, the maximum recuperation efficiency is achieved.

It is proposed to use transistor-transistor logic (TTL) for future fast, low-power digital electronic circuits. A relaxation quantum transistor can be the basic element of these circuits. This approach allows us to circumvent the difficulties of using field effect transistors based on nanowires.

Background. Static deformation of the forefoot is one of the common orthopedic pathologies, most often found in women. X-ray index of the first metatarsocuneiform joint (M1C1) is important during preoperative planning to determine the surgeon volume for surgical treatment of static forefoot deformity.Objective. To determine the radiometric prerequisites for the development of transverse platypodia depending on the structure of the first metatarsopharyngeal joint to improve the results of surgical treatment of patients.Material and methods. From 2015 to 2017, a retrospective study of X-rays of 236 feet (118 patients) performed in a standard dorsoplant projection at rest and with a functional load was carried out. Results The analysis of the obtained X-ray patterns revealed a direct dependence between the inclination of the articular surface of the medial sphenoid bone and angles of inclination of the articular surface of the base of the first phalanx of the first finger, the head of the first metatarsal bone (PASA), the intertarsal angle (M1M2) and the deflection angle of the first finger (M1P1).Conclusion. Further study of the dependence of the degree of transverse platypodia to the angle of inclination of the articular surface of the medial sphenoid bone and the use of the angle P1C1 as a prognostic indicator, in our opinion, will improve the quality of preoperative planning of surgical treatment of patients with transverse platypodia to reduce the risk of relapse.

The methods of manufacturing the matrices of the indium antimonide nanowires in regular pores of anodic alumina with various metal contacts on the different substrates have been described. It is shown, that on the basis of such matrices it is possible to create terahertz electromagnetic radiation generators as well as cooling coatings and solar cells for far-infrared and submillimeter regions of the spectrum.

Wormholes are exact solutions of Einstein’s equations and such objects are physically more likely to exist as a result of some high energy process. Using Will — Bodenner method an exact formula for light deflection is obtained. Some special features like energetics and tidal forces of the considered solution are pointed out., Кротовые норы являются точными решениями уравнения Эйнштейна. Физически подобные объекты могут существовать как результат некоторых высокоэнергетических процессов. C использованием метода Уилла — Боденнера получена точная формула для угла отклонения света. Рассмотрены и проанализированны некоторые физические особенности, такие как гравитационная энергия и приливные силы.

The study included 1172patients (410 men and 762 women) at the mean age of 60.3±10.4years with grade I-II (stage I-II) arterial hypertension (AH) admitted to the clinic of Institute of Experimental Medicine. The patients were divided into 2 groups based on the results of clinical and laboratory diagnostics. Group 1 (n=525) included patients with AH and hepatobiliary system (HBS) diseases, group 2 (n=647) patients with AH without HBS diseases. The patients group 1 had a thicker intima-media complex of carotid arteries, higher peak systolic bloodflow rate in the internal and vertebral carotid arteries, more pronounced coiling of internal carotid arteries than patients of group 2. Patients with AH and HBS diseases exhibited correlation between blood flow rate in external carotid arteries and atherogenicity coefficient. Duplex scanning of neck vessels of in patients with AH without HBS diseases revealed peculiar changes of the intima-media thickness and hemodynamically significant changes of the blood flow in the internal carotid arteries that may be of prognostic value in this nosological syntropy and require the personified approach to diagnostics, treatment, and prevention of these conditions.

The authors have theoretically substantiated the possibility to create promising thermoelectric converters based on quantum wires. The calculations have shown that the use of quantum wires with lateral dimensions smaller than quantum confinement values and high concentration and mobility of electrons, can lead to a substantial cooling of one of the contacts up to tens of degrees and to the heating of the other. The technological methods of manufacturing of indium antimonide nanowires arrays with high aspect ratio of the nanowire diameters to their length in the modified nanoporous anodic alumina matrixes were developed and tested. The microstructure and composition of the formed nanostructures were investigated. The electron microscopy allowed establishing that within each pore nanowires are formed with diameters of 35 nm and a length of 35 microns (equal to the matrix thickness). The electron probe x-ray microanalysis has shown that the atomic ratio of indium and antimony in the semiconductor nanostructures amounted to 38,26% and 61,74%, respectively. The current-voltage measurement between the upper and lower contacts of Cu/InSb/Cu structure (1 mm2) has shown that at 2.82 V negative voltage at the emitter contact, current density is 129,8 À/ñì2, and the collector contact is heated up to 75 degrees during 150 sec. Thus, the experimental results confirmed the theoretical findings that the quantum wire systems can be used to create thermoelectric devices, which can be widely applied in electronics, in particular, for cooling integrated circuits (processors), thermal controlling of the electrical circuits by changing voltage value.

The study included 1172 patients (410 men and 762 women) at the mean age of 60.3 ± 10.4 years with grade I-II (stage I-II) arterial hypertension (AH) admitted to the clinic of Institute of Experimental Medicine. The patients were divided into 2 groups based on the results of clinical and laboratory diagnostics. Group 1 (n = 525) included patients with AH and hepatobiliary system (HBS) diseases, group 2 (n = 647) patients with AH without HBS diseases. The patients group 1 had a thicker intima-media complex of carotid arteries, higher peak systolic bloodflow rate in the internal and vertebral carotid arteries, more pronounced coiling of internal carotid arteries than patients of group 2. Patients with AH and HBS diseases exhibited correlation between bloodflow rate in external carotid arteries and atherogenicity coefficient. Duplex scanning of neck vessels of in patients with AH without HBS diseases revealed peculiar changes of the intima-media thickness and hemodynamically significant changes of the blood flow in the internal carotid arteries that may be of prognostic value in this nosological syntropy and require the personified approach to diagnostics, treatment, and prevention of these conditions.

Independent experimental estimation of the instabilities of signal generators and measuring instruments is considered.

RFLP analysis of the omp1 gene was used to characterize 51 avian Chlamydophila psittaci isolates. The analysis confirmed the predominance of genotype A in parrot C. psittaci isolates and revealed new omp1 genotypes in corvid C. psittaci isolates. The corvid isolates proved to lack an extrachromosomal plasmid. The omp1 and rRNA IGS sequences were determined for the new isolates. Phylogenetic analysis showed that isolate 1V, obtained from a crow, is intermediate in several characters between C. abortus and C. psittaci. The results were compared with data on the phylogenetic relationships of earlier chlamydium isolates.

The recording of the nonstationary random process at the output of the measuring channel of the NAVSTAR satellite system is analyzed.

A mathematical model is presented for the static error of a linear electronic measuring instrument.

The properties of conversion functions of linear systems are considered as random functions of information parameters and time. It is proved on the basis of performed experiments that conversion functions of linear systems are locally homogeneous random functions of the information parameters and possess stationary increments. There is shown to be a relationship between the static characteristics of the conversion functions and the characteristics of the internal noise of the systems considered.

A study is made of the relative analysis of schemes which make it possible to estimate the random errors of measuring instruments caused by low-frequency fluctuations without using standard instruments and gauges. A choice is made of measurement procedures which possess higher reliability.

The problem is solved of experimentally determining the random error of measuring instruments without using standard and reference devices. Experimental data are presented.

An autonomous experimental estimate of the limits of possible values of the rate of change of the error of measuring instruments with time is given.

Transformation errors for linear electronic systems are analyzed that lead to presence in systems of natural low-frequency noise showing properties of local uniform random processes.

A simple criterion is considered for checking the steady state of inherent fluctuations in a linear electronic measurement system.

Basic assumptions are formulated making it possible for the first time mathematically to describe many aspects of error theory for linear measurement provisions.

The conductivity of bundles of carbon single-walled nanotubes with metallic conductivity (metallic nanotubes) is investigated over the wide temperature range 4.2-330 K and electrical fields up to 50 V. The usage of short electrical pulses of the duration of 10 ns allowed to avoid an influence of a self-heating of the investigated structures on current-voltage characteristics. It is shown that the temperature dependence of conductivity is described by the power function G proportional to T(alpha). At helium temperatures the asymptotic dependence of current on applied voltage is close to J proportional to V(1+alpha) with alpha = 0.45. From comparison of the obtained results of measurements with calculations, it is shown that the conductivity of nanotube bundles is well described within the theory of the Luttinger-liquid conductivity for one-dimensional conductors. The self-heating of the carbon nanotube bundles was observed in the case of measurements in the regime of dc current. A method for determination of the self-heating temperature of nanotube bundles as a function of an applied electrical field is proposed. The power dependence of the self-heating temperature on voltage T proportional to V(p) with the exponent p = 2.1 was observed above some threshold voltage in the temperature range 4.2-200 K. Above 200 K the exponent decreased down to p = 1.35. (C) 2011 American Institute of Physics. [doi: 10.1063/1.3662331] Simultaneous publication in Fizika Nizkikh Temperatur, volume 37, issue 8, pages 892-902 (2011).

Restriction enzyme analysis of the omp1 gene was used to characterize 51 avian Chlamydophila psittaci isolates. The analysis confirmed the predominance of genotype A in parrot C. psittaci isolates and revealed new omp1 genotypes in corvid C. psittaci isolates. The corvid isolates proved to lack an extrachromosomal plasmid. The omp1 and rRNA IGS sequences were determined for the new isolates. Phylogenetic analysis showed that isolate 1V, obtained from a crow, is intermediate in several characters between C. abortus and C. psittaci. The results were compared with data on the phylogenetic relationships of earlier chlamydium isolates.

The effects of the RTS interaction with a substrate have been researched in a 2D approximation.

Results of using a software suite intended for modelling characteristics of elements of electronic circuits depending on their topology are presented. The suite is used both for calculations in the frequency domain and for those of static parameters of circuits.

From July 25 to October 1, 1999, 826 patients were admitted to Volgograd Region, Russia, hospitals with acute aseptic meningoencephalitis, meningitis, or fever consistent with arboviral infection. Of 84 cases of meningoencephalitis, 40 were fatal. Fourteen brain specimens were positive in reverse transcriptase-polymerase chain reaction assays, confirming the presence of West Nile/Kunjin virus.

A number of experiments uses optically excited electron system of the crystal as a source of nonequilibrium phonons. Wide set of these was carried out on GaAs (see [1,2]). The frequencies of the initial acoustic phonons, generated by excited carriers or via fast intermediate stage of optical phonon creation, are up to the boundary acoustic ones. The propagation of these phonons has a complicated character, as they have short mean free paths due both to isotope scattering and anharmonic processes. Thus, there is a problem to calculate the time shapes of registered phonon pulses.

An analysis of experimental studying the stability of osteosynthesis and clinical application of apparatuses of external fixation in 282 patients with fractures and sequellae of traumas of the bones and joints of the hand is presented. Main conditions influencing stability of fixation of the hand bones were determined. A universal complex of details is recommended which allows to make the optimum construction of the device as applied to the specific kind of trauma. It was proved that choice of the individual construction of the apparatus considerably widened the scope of using the method of external fixation and improved results of the treatment.

A comparative clinical investigation of effectiveness of different methods of treatment of sequelae of injuries of the hand bones and joints in 159 patients was carried on. Traditional methods of treatment and devices for external fixation were used. An analysis of long-term results of treatment of 145 patients has shown that methods of external fixation by compressive-distraction and hinge-distraction devices are most effective.

Efficiency of different fixation methods of open fractures and dislocations of hand tubular bones on the basis of treatment experience of 206 patients has been investigated in clinical conditions. Immobilization with a plaster bandage, osteosynthesis and transarticulation fixation by wires, osteosynthesis by external fixation apparatus were used. An analysis of long-term results of treatment of 128 patients demonstrated that fixation of damaged bones and joints by the external fixation apparatus is the most effective one.

A method is given for finding the system of equations of the drift-diffusion model in the lowest order of the theory of singular peturbations. Using this approach, both the stationary and dynamic laws governing the transport processes in a semiconductor structure can be analysed.

The effect of nondiagonality of the metric tensor on the differential scattering cross section of spinor charged particles by a charged gravitational Kerr-Newman field is considered in first Born approximation. In particular cases, when the momentum of the particle before scattering: a) lies in the equatorial plane and b) is oriented along (against) the axis of rotation of a hole, expressions are obtained for the square of the scattering matrix element and the term in the cross section due to the appearance of the metric nondiagonality. The nonrelativistic and ultra-relativistic limits of these expressions are considered.

The effect of an external electromagnetic field on the magnitude of the anomalous magnetic moment (AMM) of a lepton in the Weinberg model (1967) is investigated using the method of analytic continuation, previously applied to problems in quantum electrodynamics with an external field. The behavior of the AMM is studied as a function of the value of the dynamic parameter X=poH/mHo.

The process of lepton decay into a W-boson and a neutrino and decay of a W-boson into a lepton and antineutrino in the field of a plane electromagnetic wave are considered within the framework of the Weinberg-Salam model. Exact expressions in terms of the external field are obtained for the probabilities of these processes and special cases are considered.

Exact solutions of the equations of motion of quarks in a non-Abelian field of a flat color wave of a spectral configuration are obtained. The gauge field of the wave takes values from the SU(2) group and is an exact solution of the Yang-Mills equations.