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A probabilistic–time model has been constructed for assessing the anti-interference ability of radio communication systems in electronic warfare conditions. Based on the model, a closed system of equations has been obtained, which makes it possible to estimate the anti-interference ability of radio communication channels, as well as the limiting capabilities of the reciprocal jamming station in the disruption of radio communication systems with pseudorandom operational frequency readjustment (PROFR). Numerical calculations of the dependence of the frequency switching rate of the signal with PROFR on the probability of error after countermeasures are given.

In this paper, we studied the effect of the magnetic field and temperature on conductivity of Bi2 ‒ xSbxTe3 – ySey topological insulators of different composition to identify electronic surface states in these films. The experimental data can be explained based on the model with two types of charge carriers. Thermoactivation conductivity, electron or hole, is observed in the film bulk depending on the sample composition while metal-like electronic states are found on the surface. The noticeable contribution of surface topological states to the total conductivity opens up the possibility of studying them.

This work demonstrates synthesis of metal Au nanoparticles with a plasmon resonance in the visible optical region by the spark discharge method in atmosphere of argon of purity 6.0. With raising of sintering temperature from 25 to 950 °C, the morphology of synthesized Au nanoparticles changed from agglomerates to individual particles with decreasing the median size from 270 to 90 nm according to aerosol spectrometer. While by transmission electron microscopy primary nanoparticles with a gold crystalline structure with sizes in range from 5 to 120 nm were observed. Synthesized nanoparticles ensembles had broad absorption peaks with maximum in the visible optical region with peak positions approximately at 490 nm. High temperature sintered particles had a spherical shape and an additional absorption peak at approximately 640 nm.

The literature concerning the features of creating ohmic contacts for GaAs/AlGaAs heterostructures with a two-dimensional (2D) electron gas with a high level of electron mobility is analyzed. The process of annealing the contacts based on the Ni/Au/Ge system is considered. The recommended published parameters of the layers to be sprayed and the regimes of their annealing are presented, which make it possible to obtain ohmic contacts with low resistance up to temperatures lower than 4 K. Several mechanisms are considered, which can lead to the experimentally observed dependence of the characteristics of the contact on its crystallographic orientation. A method for creating contacts using Au/Ge/Pd metallization, in which the contact is formed due to the mutual diffusion and interaction of metals and a semiconductor in the solid phase at temperatures lower than 200°C, is described. This ensures a higher degree of homogeneity of the contact in the composition and a smooth metal–semiconductor interface, and it can lead to decrease of the influence of orientation effects on the electric characteristics of the contact.

Quasi-one-dimensional semiconductor structures with a variable longitudinal potential profile are fabricated by pulse power nanolithography, which is carried out using an atomic force microscope. Structures are fabricated on the basis of AlGaAs/GaAs heterostructures with a deep (130 nm from the surface) twodimensional electron gas. The channel potential profile is formed with the help of sectioned in-plane gates formed on both channel sides. The electrical parameters of the structures measured at temperatures down to 1.5 K confirmed the efficiency of the applied method to fabricate insulating regions with lateral sizes of ~10 nm.

Alloy GeSn airborne nanoparticles (NP) with the rate of atomic content of Sn to Ge 30 % were produced by spark discharge during simultaneous erosion of germanium and tin electrodes in atmosphere of argon of purity 6.0. Then NP were moved by gas flow to a tube furnace, which were mounted directly after discharge chamber, and sintered at temperatures from 25 to 750 °C. The change of morphology, element composition and crystal structure of NP were investigated using transmission electron microscopy (TEM) with energy dispersive X-ray analysis (EDX), aerosol spectrometer and Fourier-transform infrared spectroscopy (FTIR). Agglomerates of predominantly amorphous primary NP with the mean size of 7 nm were obtained at low sintering temperatures of the tube furnace (25 and 200 °C). High temperature (550 and 750 °C) flow-through thermal sintering of NP agglomerates resulted in production of individual crystal NP with an average size of 28 nm with various crystal structures.

This paper reviews the literature concerning the specifics of creating Ohmic contacts to AlGaAs/GaAs heterostructures with a 2D electron gas with high electron mobility. The process of annealing the contacts based of the Ni/Au/Ge system is considered, and the recommended parameters of the metalization layers are borrowed from the literature. This process allows reproducible fabrication of Ohmic contacts with a low electrical resistance to temperatures below 4K. Several mechanisms are analyzed which could result in the experimentally observed dependence of the contact parameters on crystallographic orientation. A method of contact fabrication with Au/ Ge/Pd metallization is described for which the contact is formed by mutual diffusion and interaction of the metals and the semiconductor in the solid phase at temperatures below 200 °C. This provides for high composition homogeneity of the contacts, a smooth metal / semiconductor boundary and can reduce the effect of orientation on the electric characteristics of the contact.

The paper provides the first interim analysis of a database including information on 806 metastatic kidney cancer patients receiving targeted therapy in the cancer facilities of the Moscow Healthcare Department. It shows a comparative analysis of the periods of first-line targeted therapy with different drugs until progression is established.

We analyzed telomere length of individual chromosomes in peripheral blood lymphocytes of healthy individuals and patients with rheumatoid arthritis. Quantitative fluorescent in situ hybridization and subsequent computer analysis of metaphase chromosomes showed that distribution of telomere length on individual chromosomes is different under normal and pathological conditions. Patients with rheumatoid arthritis had significantly shorter chromosome 4p telomeres, which can be essential for pathogenesis of this multifactorial disease. Additionally, disease activity inversely correlated with telomere length on chromosome 10p carrying genes involved in T cell differentiation and proliferation.

The paper represents the investigations of dimensional and structural properties of nanoparticles produced by pulsed-periodic spark discharge by simultaneous electrical erosion of germanium and tin electrodes in inert atmosphere. Two alloys of GeSn nanoparticles with different mass fractions of tin were obtained by altering the polarity of the electrodes. The nanoparticles’ sizes from 4 to 45 nm were observed. It was shown that the samples consist of core-shell nanoparticles agglomerates, where both β-tin crystals and cubic germanium ones presence as a core; the shell is a mixed germanium tin oxide. Furthermore, a shift of a maximum of Raman peak by 3.5 cm−1 to lower wave numbers with an increase in relative fraction of tin was detected.

In this paper, we demonstrate an ability to produce aerosol metal Al nanoparticles with plasmon resonance in the ultraviolet region in a spark discharge generator in pure argon atmosphere. The sizes of the obtained primary particles with metal Al core and natural oxide shell in the range from 4 to 50 nm, which were collected in agglomerates with mean size from 190 to 260 nm, were observed. Simulation extinction spectra according to Mi theory for obtained particle ensembles were calculated. It was experimentally and theoretically found that obtained nanoparticles ensembles demonstrate the broad extinction peaks with maximum below 250 nm depending on the synthesis conditions.

We analyzed the research data on antitumor effects of a wide range of ferrocene compounds and discussed possible mechanisms of their bioactivities. Current trends in the study of anticancer effects of ferrocene derivatives were considered. Promising ways in the design of low-toxicity anticancer ferrocene-based drugs of new generation were outlined.

The paper provides the first interim analysis of a database including information on 427 metastatic kidney cancer patients receiving targeted therapy in the cancer facilities of the Moscow Healthcare Department. It shows a comparative analysis of the periods of first-line targeted therapy with different drugs until progression is established.

We propose a new operation mode for an atomic force microscope (vertical mode), which can be used to measure the topography and other physical parameters of a surface with deep pores, vertical walls, and significant height differences. The measurement of height in this mode is conducted upon vertical uniform motion of the probe towards the surface. Corresponding AFM images are presented.

A significant telomere shortening was shown in both total peripheral lymphocyte populations and CD4+ T-cells from patients with bronchial asthma, as compared to normal donors. Such shortening takes place in different cell subpopulations depends on different types of bronchial asthma. In patients with intrinsic asthma, a telomere contraction was found both in CD4+ and CD8+T-lymphocytes, but only in CD4+ lymphocytes from patients with extrinsic-type asthma. We didn’t found any changes of telomere length in patients with mixed-type asthma, however, a significant correlation was found between telomere length in both CD4+ and CD8+T- cells, and serum IgE concentrations. The data obtained demonstrate that telomere shortening in lymphocytes may take place not only due to T-cell exhaustion, or homeostatic proliferation induced by lymphopenia, but also due to expansion of antigenreacting cells. The entire data point to sufficient pathogenetic differences for various types of bronchial asthma. A non-uniform contribution of atopic and infectious inflammation may present an important reason for different patterns of the disease development.

In this article the authors on the basis of the analysis of the medical literature describe the purpose, chemotherapy options and future de-velopment in chemotherapy in patients with triple-negative breast cancer.

The results of research of tribological properties of polymeric materials for the seals of movable connections are brought in conditions of volume compression using the method of complete multifactorial experiment. Regressive equations adequately describing the dependence of wear intensity and friction coefficient of materials at their co-operating with a counter-body (steel of 40Х), from hydrostatical pressure, speed of skidding and temperature of working liquid are given. It is determined that the preferable complex of tribological descriptions is possessed by the rubber under the code number 7-ИРП-1269″ and the fluorine plastic Ф4К20″.

Transistor structures with one-dimensional conducting channel and three-sectioned side control gates have been created based on GaAs/AlGaAs heterostructures with two-dimensional electron gas by means of local anode oxidation with the aid of a scanning probe microscope. It is demonstrated that gates in this structure allow the potential profile in the channel to be controlled. The measured dependences of the channel conductance on the gate voltage exhibit plateaus (including those not multiple of 2e2/h) and maxima, the positions of which are determined by the ratio of potentials applied to the gates.

Electron-beam lithography and ion etching of GaAs/AlGaAs heterostructures are used to create transistor structures with a qusi-1D ballistic channel and side control gates. A plateau of the conductance quantization is observed up to unusually high temperatures (up to 50 K) along with the hysteresis effect. It is demonstrated that such features are related to the presence of a narrow strip of positive charge in the doped layer in AlGaAs, this strip being the result of the etching in the vicinity of the channel.

Premature shutdown of electrolytic baths after a short service life leads to an increase in the cost of aluminum and serious economic losses. The most important element governing the service life of an electrolytic bath is the hearth that is lined with refractory hearth blocks. Presence of one concealed crack, that is exposed in the start-up period, may lead to failure of the whole electrolyzer in the first year of service. There are many producers and users of hearth blocks, and there are many specifications for cathode hearth blocks, although the requirements for them are selected in a very empirical way without considering actual service conditions. Scientifically based requirements for the material of hearth blocks is still in the formation stage. In 2004 in four aluminum enterprises under major repair hearth blocks were used from nine different producers that made it possible during evaluation of the statistics for shutting down young baths to determine the effect of the structure and properties of hearth blocks on the service life of electrolyzers and to formulate requirements for hearth block material. The contribution of permeable porous cathode carbon blocks on premature shutdown of electrolyzers by a mechanism of hearth uplift due to formation of a lens of electrolyte and refractory reaction products is demonstrated. Critical gas permeability and the maximum size of permeable pores in refractory hearth units are determined. Applicability of the first and second Hasselman criteria for the heat resistance of hearth block materials is demonstrated for predicting shutdown of young baths by a crack development mechanism in blocks due to thermomechanical stresses.

The rectification of current has been observed in a quasi-one-dimensional ballistic quantum channel. The effect is explained by the asymmetry of the potential profile in the channel. The dependence of the rectified current on the height of the potential barrier in the channel exhibits sharp maxima, which are associated with conductance quantization steps. A model of the rectification is proposed.

Results of an experimental study of the physicomechanical properties of refractory materials for the lining of aluminum electrolyzers are reported.

An original technique and results of experimental evaluation of the relationship between «external» and «internal» wears of used seals of hydraulic power cylinders’ movable joints are presented.

Culturing of polyclonally activated T lymphocytes for 7 days in vitro leads to telomere lengthening in CD8(+), but not CD4(+)lymphocytes. Under these conditions, CD8(+)lymphocytes more intensively express telomerase catalytic subunit protein (hTERT) and divide more often than CD4(+)lymphocytes. It changes the ratio of CD4(+)and CD8(+)subpopulations in favor of the latter by the end of culturing.

This method makes it possible to measure the fluorescence of a DNA probe in cells with known division number and targeted surface antigen. In fact, this method is a combination or consistent application of three other methods: cell tracking by vital dye, surface immunophenotyping, and flow-FISH. The idea in developing this method was to study telomere length changes in cells with known surface antigen after every new cell division. First, the in vitro cell culturing and staining with CFSE vital dye are performed. Then, cells are stained with surface MAbs labeled with biotin, followed by incubation with streptavidin-labeled fluorochrome. After that, cells are fixed with BS(3) reagent followed by the flow-FISH procedure with PNA-probe complementary to telomere DNA repeats. Finally, in one tube, it is possible to determine telomere length in surface antigen-labeled cells that have made the exact same number of divisions after incubation.

We propose a mechanism to explain the electric instability often observed in modulation-doped heterostructures GaAs/AlGaAs when current is passed along the heterostructure layers. The instability is caused by hot electron transport in AlGaAs layer that is not only heavily doped, but also strongly compensated due to the presence of DX-centers. This layer contains a large-scale random potential of significant magnitude, which strongly affects electron transport. The heating of electrons in the percolation cluster net and electron transfer from the cluster into the random potential wells result in the appearance of latent negative differential conductivity causing the current instability. When the instability gives rise to the formation of a high electric field domain, one of the domain walls blocks the current flow through the two-dimensional electron gas. Experimental results supporting this mechanism are given.

We investigated the influence exerted by the radius of the bend of fiber light guides with light-transmitting cores of different diameters on the transformation of the spectrum of longitudinal modes of the semiconductor laser radiation introduced into them. It is shown that the bended segment of the light guide acts as a spectrum selector, and the spectral composition of the radiation at the output of a light guide is different in different spots of the speckle structure.

Китрил является высокоэффективным препаратом для профилактики тошноты и рвоты у больных, получающих как высокоэметогенную, так и среднеэметогенную химиотерапию. Кроме того, высокий процент полного купирования тошноты и рвоты достигается как при внутривенном введении, так и при приеме китрила внутрь; это значительно облегчает лечение, улучшает качество жизни больных, что подтверждают сами пациенты.