The results of studies in which the relationship of the self-organization, physicochemical properties, and bioeffects in dilute aqueous solutions of various biologically active substances sustained ...under natural and reduced levels of external physical fields (geomagnetic and low-frequency electromagnetic), as well as under exposure to ionizing radiation solutions studied by the complex of physicochemical methods, are considered. The established patterns can be used to create a scientific base related to the clarification of the mechanisms of the negative influence of hypomagnetic conditions on the functioning of living organisms necessary to ensure the normal operation of the ecosystem of spacecraft during flights.
The results of the development of methods for the transfer of units of water content in solid and liquid substances and materials are presented. Four types of comparison standards have been created ...for the transfer of units of water content, reproduced at the State Primary Standard of units of mass fraction, mass (molar) concentration of water in solid and liquid substances and GET 173–2017 materials. The procedures for the preparation of reference standards materials based on a mixture of organic solvents that are stable in water content and sodium molybdate dihydrate, which has chemically bound (crystallized) water, are described. The methods of reproducing the units of water content used in determining the characteristics of reference standards are presented: coulometric and volumetric Karl Fischer titration, air-heat drying and thermogravimetric analysis with mass spectrometric detection. The characteristics and standard uncertainties of the comparison standards, due to the characterization method, heterogeneity, long-term and short-term instabilities, are evaluated. The main changes adopted within the framework of the processing of the State verification scheme for means of measuring the water content in solid and liquid substances and materials are described.
bioprinting is one of the most clinically relevant techniques in the emerging bioprinting technology because it could be performed directly on the human body in the operating room and it does not ...require bioreactors for post-printing tissue maturation. However, commercial
bioprinters are still not available on the market. In this study, we demonstrated the benefit of the originally developed first commercial articulated collaborative
bioprinter for the treatment of full-thickness wounds in rat and porcine models. We used an articulated and collaborative robotic arm from company KUKA and developed original printhead and correspondence software enabling
bioprinting on curve and moving surfaces. The results of
and
experiments show that
bioprinting of bioink induces a strong hydrogel adhesion and enables printing on curved surfaces of wet tissues with a high level of fidelity. The
bioprinter was convenient to use in the operating room. Additional
experiments (
collagen contraction assay and
3D angiogenesis assay) and histological analyses demonstrated that
bioprinting improves the quality of wound healing in rat and porcine skin wounds. The absence of interference with the normal process of wound healing and even certain improvement in the dynamics of this process strongly suggests that
bioprinting could be used as a novel therapeutic modality in wound healing.
A linear resonant pulsed accelerator of heavy ions with an energy of 4 MeV/nucleon, an operating frequency of 162.5 MHz, and a current of up to 10 mA is being developed at the National Research ...Center “Kurchatov Institute” (the Kurchatov Complex of Theoretical and Experimental Physics (KCTEP)). The high-energy beam transport (HEBT) channel is designed for transporting a beam of accelerated ions with
A
/
Z
= 4–8 to the ion stripping target before their injection into the booster. The main channel elements and their parameters, which provide transversal beam focusing and minimize the momentum spread of particles, have been determined. Some results of dynamic calculations in the HEBT channel with the use of three-dimensional models for the spatial distribution of a magnetic quadrupole lens field and an electrical debuncher field are presented.
This work presents the results of a comparative study of dielectric and pyroelectric properties of aluminum nitride (AlN) single-layer and multilayer samples with a thickness of 100 ÷ 200 μm grown in ...the 0001 direction by chloride-hydride epitaxy. A silicon wafer covered by silicon carbide nanolayer grown by solid-phase substitution (SiC/(111)Si) was used as a substrate for subsequent growth of AlN single crystalline layers. The samples were formed by layer-by-layer growth. It is shown that such method makes it possible to change the orientation of the polar hexagonal axis in AlN single crystals.
The present work is a comprehensive study of the ionospheric vertical total electron content (vTEC) variations during the nighttime, based on data collected by ground‐based Global Navigation ...Satellite System (GNSS) receivers over the Latin American region. We provide a qualitative and quantitative analysis of the ionospheric vTEC trend at 21:00, 00:00, and 03:00 local time (LT), during geomagnetically undisturbed days of 2011 (ascending phase) and 2014 (maximum phase), which encompassed (a) the response to the solar flux variation, (b) the seasonal trend in different latitudes and longitudes, and (c) the interhemispheric asymmetry. One significant result of this study is the development of TEC maps for the Latin American region, which are used for the monitoring and forecasting of the ionosphere for space weather purposes. The nighttime vTEC variations showed a strong latitudinal dependence, especially in the Northern Hemisphere. For 2011, the semiannual anomaly was similar to that observed in daytime; however, in 2014, the receivers at midlatitude presented asymmetric behavior. Similarly, the nighttime winter anomaly (NWA) was very weak in both years. The Equatorial Ionospheric Anomaly (EIA) signature was absent from June to August, a period in which the hemispheric disparity in the vTEC values became more evident, suggesting a feeble interhemispheric circulation. The Midlatitude Summer Nighttime Anomaly (MSNA) was also identified in the Southern Hemisphere, during January and February of 2011 (moderate solar activity). Model approximations suggest that the equatorward winds and the EIA were involved in the formation of the MSNA.
Key Points
TEC maps for the Latin American region have been developed as a tool for analyzing the spatial and temporal nighttime ionosphere variations
The MSNA was analyzed in terms of downward plasma fluxes and equatorward winds registered during January and December
The seasonal variability of the ionosphere over this region, including the EIA and the MSNA, became no longer significant after midnight
Granules of a chitosan–titanium dioxide composite material with different concentrations of titanium dioxide nanoparticles for agricultural use are obtained. The average diameter of the granules is ...35 mm. It is shown that varying the concentration of titanium dioxide nanoparticles in the composite material within the studied limits does not affect the structure of its surface. Experiments are carried out in situ on the seeds of cucumber (
Cucumis sativus
). It is noted that, during the first three weeks, the composite material has an inhibitory effect on plant growth, and then, after the onset of dissolution of the granules, it has a growth-stimulating effect. The best growth rates are observed when two granules of a composite material with a ratio of chitosan to titanium dioxide of 3 to 1 are added to the soil. It is concluded that the obtained granules of a chitosan–titanium dioxide composite material can have a positive effect on the processes of plant growth and formation.
Influenza viruses cause acute respiratory infections, especially in the autumn–winter period. They are characterized by a high mutation frequency and cause annual seasonal epidemics. The detection of ...antibodies that neutralize the virus is an important criterion in the assessment of population immunity and the influenza vaccine effectiveness. In this study, a method for determining the titer of virus-neutralizing antibodies in blood serum has been developed. A new test called the luciferase neutralization assay uses a bioluminescent signal for detection. The assay is based on engineered influenza reporter viruses with various surface antigens and a nanoluciferase reporter protein in the NS1 reading frame. Using the developed method, we studied paired sera of volunteers obtained before and after vaccination. The proposed assay was compared with the conventional antibody assessment methods (microneutralization and hemagglutination inhibition assay); a high degree of correlation was observed. At the same time, the use of the luciferase neutralization assay made it possible to reduce the time required for the analysis and to simplify the detection procedure.