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When studying the effect of vaccines against influenza, attention is mainly paid to obtaining high titers of protective antibodies in the blood and reducing the incidence of respiratory infections among vaccinated people. At the same time, the changes occurring in patient,s body from the factors of local specific and innate immunity remain insufficiently studied. The aim of the study was to determine the effect of parenteral influenza vaccination on the state of local immunity, cytology and microbiota of oropharyngeal secretion (OS) in patients with chronic inflammatory diseases of the upper respiratory tract. The study of immunological and microbiological parameters was performed in 32 patients with chronic inflammatory diseases of the upper respiratory tract, including 11 diagnosed with chronic rhinosinusitis, 9 – with chronic tonsillitis, 12 – with chronic pharyngitis, 3 and 12 weeks after vaccination with trivalent inactivated influenza-vaccine (PASTEUR, SA, France), which was administered intramuscularly. Single vaccination against influenza A and B has been shown to normalize reduced local humoral immunity indices, in particular sIgA and immune complexes concentrations, increase lymphocyte output to oropharyngeal secretions and cause a significant decrease in the representation of OS transient microflora without affecting the overall level of bacterial contamination. In both periods after the vaccination the reduced content of interferon-α in the OS of patients with chronic inflammatory diseases of the upper respiratory tract did not change. The obtained data allow to recommend vaccination against influenza virus in the period up to 3 months before the the beginning of mass infections as an effective means of stimulating the protective reactions of local immunity of oropha­rynx and nasopharynx mucous membranes in patients with chronic inflammatory diseases of the upper respiratory tract.

Relevance. Until recently, the issues of changes in immunological and microbiological parameters of the oropharynx in vaccinated against viral infections remain insufficiently covered. Objective: to determine the effect of parenteral influenza vaccination on the cellular and microbial composition of the oropharyngeal secretion in patients with chronic inflammatory diseases of the upper respiratory tract with the presence of anamnestic antibodies to vaccine strains of viruses. Materials and methods. Oropharyngeal secretion samples of 18 patients with chronic inflammatory diseases of the upper respiratory tract studied before and 3, 12, and 36 weeks after vaccination with inactivated split influenza vaccine. As control 25 donors were used. The cell composition of the sediment was determined. A microbiological study of the oropharyngeal secretion was performed. Results. At 3 and 12 weeks after vaccination, vaccinated patients significantly changed the relative rates of entry into the oropharyngeal secretion of lymphocytes and the composition of its microbiota while maintaining its total number. After 36 weeks, the cell composition and the representation of pathogenic and opportunistic microflora practically returned to baseline with a significant increase in the total microbiota. Conclusions. Parenteral administration of inactivated split vaccine to persons with chronic inflammatory diseases of the upper respiratory tract with the presence in the blood of anamnestic antibodies to vaccine strains of viruses is accompanied by a simultaneous temporary increase in lymphocyte representation with a simultaneous decrease in the number of transfusion microflora in the oropharyngeal secretion.

In this study, a composite with alternate layers of 5056 and 1580 alloys was manufactured with wire arc additive manufacturing technology. It is shown that increased strength characteristics of composite material can be obtained with deformation treatment using a high-pressure torsion (HPT) technique. The microstructure and mechanical properties of the HPT-processed material in different structural states were investigated. The HPT-processed material exhibits a high value of ultimate tensile strength (~770 MPa) but low ductility. Short-term annealing at 250 °C and additional deformation with HPT to 0.25 of revolution at room temperature resulted in a slight decrease in the material’s strength to ~700 MPa but provided ductility of ∼9%. Physical mechanisms to improve plasticity in correlation with microstructure evolution are discussed.

In recent years, additive manufacturing of products made from 5000 series alloys has grown in popularity for marine and automotive applications. At the same time, little research has been aimed at determining the permissible load ranges and areas of application, especially in comparison with materials obtained by traditional methods. In this work, we compared the mechanical properties of aluminum alloy 5056 produced by wire-arc additive technology and rolling. Structural analysis of the material was carried out using EBSD and EDX. Tensile tests under quasi-static loading and impact toughness tests under impact loading were also carried out. SEM was used to examine the fracture surface of the materials during these tests. The mechanical properties of the materials under quasi-static loading conditions exhibit a striking similarity. Specifically, the yield stress σ0.2 was measured at 128 MPa for the industrially manufactured AA5056_IM and 111 MPa for the AA5056_AM. In contrast, impact toughness tests showed that AA5056_AM KCVfull was 190 kJ/m2, half that of AA5056_IM KCVfull, which was 395 kJ/m2.

The proposed model uses modern concepts of mechanics as well as solid-state physics and metal physics to consider the behaviours of single- and polycrystalline states of metal materials in the conditions of uniform compression, when there are two types of model stress concentrators: subtraction and interstitial ones, which are analogous to the majority of the stress risers appeared in the real products. The features of the stress concentrators’ behaviours and the changing sequences of their quantity and power are demonstrated depending on their stability in the spheroidal samples. The differences in the stress increase and relaxation at the tips, which regulate the activity of the known relaxation mechanisms, are pointed out. For both the single- and polycrystalline states, the existence of critical points on the pressure axis, which limit the collective activity of vacancy and dislocation mechanisms of plastic relaxation and transition to the accumulation of only interstitial point defects with the increasing pressure, is predicted. These interstitial defects facilitate a considerable increase of potential energy of atoms in the conditions of elastic decrease of the crystal lattice parameter. The growth is accelerated near the stable stress concentrators. Priorities and peculiarities of participation of the stress concentrators in the formation of the hydrodynamic state of materials are considered. The model allows explaining majority of the experimental results related to mechanical behaviour of materials after the uniform compression. It also predicts the probability of formation of new structural states in the conditions of the rapidly decreased pressure from the certain critical value.

The gas turbine engine’s (GTE) development aims for the increasing the efficiency, strength, reliability and safety of its components. To create competitive engines, housing parts and components with high functionality and reduced weight are needed. Especially difficult in the design and production are the gearboxes for aviation GTE. Traditional technologies based on precision casting or material forming operations have significant limitations due to the complexity of fulfilling multiple different requirements. Nowadays, one of the progressive production techniques is additive manufacturing. The article presents the results of computational and experimental studies that substantiate the applicability of laser additive technology to reduce the mass of body parts by up to 15% while ensuring their strength properties. The physical and mechanical characteristics of aluminum alloys acceptable for the manufacturing of housing parts were analyzed. The necessary characteristics of the powder alloy of the Al-Si system and the technological parameters of the L-PBF of the modified housing of the gear reducer are established. Using the finite element method (FEM) the L-PBF process was numerically simulated and the technological modes for synthesis of the AlSi10Mg alloy powder were optimized. With the help of a serial 3D printer ProX320DMP, the prototype of a gear housing was manufactured.

In recent years, additive manufacturing of products made from 5000 series alloys has grown in popularity for marine and automotive applications. At the same time, little research has been aimed at determining the permissible load ranges and areas of application, especially in comparison with materials obtained by traditional methods. In this work, we compared the mechanical properties of aluminum alloy 5056 produced by wire-arc additive technology and rolling. Structural analysis of the material was carried out using EBSD and EDX. Tensile tests under quasi-static loading and impact toughness tests under impact loading were also carried out. SEM was used to examine the fracture surface of the materials during these tests. The mechanical properties of the materials under quasi-static loading conditions exhibit a striking similarity. Specifically, the yield stress σ 0.2 was measured at 128 MPa for the industrially manufactured AA5056_IM and 111 MPa for the AA5056_AM. In contrast, impact toughness tests showed that AA5056_AM KCVfull was 190 kJ/m2, half that of AA5056_IM KCVfull, which was 395 kJ/m2. [ABSTRACT FROM AUTHOR]

Proceeding with the analysis of Amata et al. (2005), we suggest that the general feature for the local transport at a thin magnetopause (MP) consists of the penetration of ions from the magnetosheath with gyroradius larger than the MP width, and that, in crossing it, the transverse potential difference at the thin current sheet (TCS) is acquired by these ions, providing a field-particle energy exchange without parallel electric fields. It is suggested that a part of the surface charge is self-consistently produced by deflection of ions in the course of inertial drift in the non-uniform electric field at MP. Consideration of the partial moments of ions with different energies demonstrates that the protons having gyroradii of roughly the same size or larger than the MP width carry fluxes normal to MP that are about 20% of the total flow in the plasma jet under MP. This is close to the excess of the ion transverse velocity over the cross-field drift speed in the plasma flow just inside MP (Amata et al., 2005), which conforms to the contribution of the finite-gyroradius inflow across MP. A linkage through the TCS between different plasmas results from the momentum conservation of the higher-energy ions. If the finite-gyroradius penetration occurs along the MP over ~1.5 RE from the observation site, then it can completely account for the formation of the jet under the MP. To provide the downstream acceleration of the flow near the MP via the cross-field drift, the weak magnetic field is suggested to rotate from its nearly parallel direction to the unperturbed flow toward being almost perpendicular to the accelerated flow near the MP. We discuss a deceleration of the higher-energy ions in the MP normal direction due to the interaction with finite-scale electric field bursts in the magnetosheath flow frame, equivalent to collisions, providing a charge separation. These effective collisions, with a nonlinear frequency proxy of the order of the proton cyclotron one, in extended turbulent zones are a promising alternative in place of the usual parallel electric fields invoked in the macro-reconnection scenarios. Further cascading towards electron scales is supposed to be due to unstable parallel electron currents, which neutralize the potential differences, either resulted from the ion- burst interactions or from the inertial drift. The complicated MP shape suggests its systematic velocity departure from the local normal towards the average one, inferring domination for the MP movement of the non-local processes over the small-scale local ones. The measured Poynting vector indicates energy transmission from the MP into the upstream region with the waves triggering impulsive downstream flows, providing an input into the local flow balance and the outward movement of the MP. Equating the transverse electric field inside the MP TCS by the Hall term in the Ohm's law implies a separation of the different plasmas primarily by the Hall current, driven by the respective part of the TCS surface charge. The Hall dynamics of TCS can operate either without or as a part of a macro-reconnection with the magnetic field annihilation.

Studies of the auroral plasma with small-scale inhomogenieties producing the VHF-radar reflections (radar aurora) when observed in conditions of the saturated Farley-Buneman instability within the auroral E region, show strong nonlinear interactions and density fluctuations of 5–15%. Such nonlinearity and high fluctation amplitudes are inconsistent with the limitations of the weak turbulence theory, and thus a theory for arbitrary amplitudes is needed. To this end, a nonlinear theory is described for electrostatic MHD moving plasma structures of arbitrary amplitude for conditions throughout the altitude range of the collisional auroral E region. The equations are derived, from electron and ion motion self-consistent with the electric field, for the general case of the one-dimensional problem. They take into account nonlinearity, electron and ion inertia, diffusion, deviation from quasi-neutrality, and dynamical ion viscosity. The importance of the ion viscosity for dispersion is stressed, while deviation from the quasi-neutrality can be important only at rather low plasma densities, not typical for the auroral E region. In a small amplitude limit these equations have classical nonlinear solutions of the type of "electrostatic shock wave" or of knoidal waves. In a particular case these knoidal waves degrade to a dissipative soliton. A two-dimensional case of a quasi-neutral plasma is considered in the plane perpendicular to the magnetic field by way of the Poisson brackets, but neglecting the nonlinearity and ion inertia. It is shown that in these conditions an effective saturation can be achieved at the stationary turbulence level of order of 10%.