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The grain of rye (Secale cereale L.) used for baking contains a large amount of non-starch polysaccharides, making it an excellent component of functional foods. But rye grain intended for alcohol production and forage use should have a reduced content of these polysaccharides. A comprehensive parameter that can predict the best field of application for winter rye grain is the viscosity of its wholemeal water extract. However, our understanding of the genetic background underlying this key trait and associated features of rye grain is poor. By analyzing six Russian winter rye cultivars, we identified the most contrasting forms and characterized the peculiarities of their water-soluble carbohydrates capable of influencing the viscosity of water extracts. Then, using phylogenetic and transcriptomic analyses, we identified in the rye genome many genes encoding putative glycosyltransferases and glycosylhydrolases responsible for the synthesis and degradation of arabinoxylans, mixed-linkage glucans, cellulose, and some other polysaccharides. We determined the dynamics of mRNA abundance for these genes at three stages of kernel development. Comparisons of gene expression levels in two contrasting cultivars revealed specific members of multigene families that may serve as promising targets for manipulating non-starch polysaccharide content in rye grain. High-viscosity cultivars were characterized by up-regulation of many glycosyltransferases involved in the biosynthesis of arabinoxylans and other cell-wall polysaccharides, whereas low-viscosity cultivars showed up-regulation of several genes encoding polysaccharide-degrading enzymes.

Objective – obtaining and characterization of hybrid cell lines producing monoclonal antibodies against I and II types of shiga-like toxins.Materials and methods. Shiga-like toxins obtained in “48thCentral Research Institute” of Ministry of Defense of Russian Federation (Kirov), BALB/c mice, myeloma cells SP2/0-Ag14 were used in research. Immune splenocytes and SP2/0-Ag14 myeloma cells were fused according to G. Kohler and C. Milstein method in De St. Fazekas and D. Scheidegger modifcation using 50 % polyethylene glycol. Hybrid cell lines producing specifc monoclonal antibodies were cloned by limited dilutions. Hybridomas growth and producing properties were studied in vitro and in vivo. Specifc activity of immune sera, culture and ascitic fluids were studied by indirect ELISA. Monoclonal antibodies from ascitic fluids were precipitated by saturated ammonium sulfate, followed by ion exchange chromatographyResults and discussion. 8 hybridomas producing monoclonal antibodies against I and II types shiga-like toxins were obtained. Hybridomas are characterized by stable proliferation and antibody-producing activity during 10 passages in vitro and 3 passages in vivo (observation period). Obtained monoclonal antibodies can be used for ELISA detection of I and II types shiga-like toxins. Minimum detectable concentration of shiga-like toxins in sandwich ELISA is 1 ng/ml. The possibility of detecting shiga-like toxins without typical differentiation was shown when using in the enzyme immunoassay a polyreceptor mixture of monoclonal antibodies for sensitizing the plate and a polyspecifc mixture of immunoperoxidase conjugates.

The PAM-Stamp 2G software package is used to simulate the tool bending of a workpiece made of an AMg5 aluminum alloy with and without taking into account the heat-affected zone (HAZ) formed during laser cutting of a sheet. The option of calculating welded workpieces is adapted to describe the HAZ. The state of stress in the workpiece during bending at various bending radii is analyzed with allowance for various HAZ widths. The influence of HAZ up to 4.5 mm wide on the workpiece thickness during bending is found to be insignificant.

Background and Aims Plant diseases caused by Pectobacterium atrosepticum are often accompanied by extensive rot symptoms. In addition, these bacteria are able to interact with host plants without causing disease for long periods, even throughout several host plant generations. There is, to date, no information on the comparative physiology/biochemistry of symptomatic and asymptomatic plant–P. atrosepticum interactions. Typical (symptomatic) P. atrosepticum infections are associated with the induction of plant responses mediated by jasmonates, which are one of the products of the lipoxygenase cascade that gives origin to many other oxylipins with physiological activities. In this study, we compared the functioning of the lipoxygenase cascade following typical and latent (asymptomatic) infections to gain better insight into the physiological basis of the asymptomatic and antagonistic coexistence of plants and pectobacteria. Methods Tobacco plants were mock-inoculated (control) or infected with the wild type P. atrosepticum (typical infection) or its coronafacic acid-deficient mutant (latent infection). The expression levels of the target lipoxygenase cascade-related genes were assessed by Illumina RNA sequencing. Oxylipin profiles were analysed by GC-MS. With the aim of revising the incorrect annotation of one of the target genes, its open reading frame was cloned to obtain the recombinant protein, which was further purified and characterized using biochemical approaches. Key Results The obtained data demonstrate that when compared to the typical infection, latent asymptomatic P. atrosepticum infection is associated with (and possibly maintained due to) decreased levels of 9-lipoxygenase branch products and jasmonic acid and increased level of cis-12-oxo-10,15-phytodienoic acid. The formation of 9-oxononanoic acid and epoxyalcohols in tobacco plants was based on the identification of the first tobacco hydroperoxide lyase (HPL) with additional epoxyalcohol synthase (EAS) activity. Conclusions Our results contribute to the hypothesis of the oxylipin signature, indicating that different types of plant interactions with a particular pathogen are characterized by the different oxylipin profiles of the host plant. In addition, the tobacco LOC107825278 gene was demonstrated to encode an NtHPL (CYP74C43) enzyme yielding volatile aldehydes and aldoacids (HPL products) as well as oxiranyl carbinols (EAS products).

Iron-doped potassium titanate with a hollandite structure is synthesized by the solid-phase method. To reduce the contact resistance and to increase the diffusion coefficient of potassium ions, a conductive carbon coating is applied to the surface of the titanate synthesized in an argon atmosphere. The formation of the composite material is confirmed by the results of X-ray phase analysis, scanning electron microscopy, and IR spectroscopy. The half-cells with potassium metal in a CR2025 case, which are assembled on the basis of the synthesized composite, are tested electrochemically with subsequent calculation of the specific capacitance, power density, and energy density. It is found that the specific capacitance of an electrode with a carbon coating is 10–15% higher with low sweep rates (1 and 3 mV s–1). It is shown that the use of carbon coatings increases the diffusion coefficient of potassium to 1.77 × 10–14 cm2 s–1/2.

Yana Toropova,1 Dmitry Korolev,1 Maria Istomina,1,2 Galina Shulmeyster,1 Alexey Petukhov,1,3 Vladimir Mishanin,1 Andrey Gorshkov,4 Ekaterina Podyacheva,1 Kamil Gareev,2 Alexei Bagrov,5 Oleg Demidov6,7 1Almazov National Medical Research Centre, Ministry of Health of the Russian Federation, Saint-Petersburg, 197341, Russian Federation; 2Saint Petersburg Electrotechnical University “LETI”, Saint-Petersburg, 197376, Russian Federation; 3Personalised Medicine Center, Almazov National Medical Research Centre, Ministry of Health of the Russian Federation, Saint-Petersburg, 197341, Russian Federation; 4FSBI “Research Institute of Influenza named after A.A. Smorodintsev “ Ministry of Health of Russian Federation, Saint-Petersburg, Russian Federation; 5Sechenov Institute of Evolutionary Physiology and Biochemistry, Russian Academy of Sciences, Saint-Petersburg, Russian Federation; 6Institute of Cytology RAS, Saint-Petersburg, 194064, Russian Federation; 7INSERM U1231, Faculty of Medicine and Pharmacy, University of Bourgogne-Franche Comté, Dijon, FranceCorrespondence: Yana ToropovaAlmazov National Medical Research Centre, Ministry of Health of the Russian Federation, Saint-Petersburg, 197341, Russian FederationTel +7 981 9564800Fax +7 812 4997069Email yana.toropova@mail.ruBackground: A promising approach to solve the problem of cytostatic toxicity is targeted drug transport using magnetic nanoparticles (MNPs).Purpose: To use calculation to determine the optimal characteristics of the magnetic field for controlling MNPs in the body, and to evaluate the efficiency of magnetically controlled delivery of MNPs in vitro and in vivo to a tumour site in mice.Material and Methods: For the in vitro study, reference MNPs were used, while for in vivo studies, MNPs coated in polylactide including fluorescent indocyanine (MNPs-ICG) were used. The in vivo luminescence intensity study was performed in mice with tumours, with and without of a magnetic field at the sites of interest. The studies were performed on a hydrodynamic stand developed at the Institute of Experimental Medicine of the Almazov National Medical Research Centre of the Ministry of Health of Russia.Results: The use of neodymium magnets facilitated selective accumulation of MNPs. One minute after the administration of MNPs-ICG to mice with a tumour, MNPs-ICG predominantly accumulated in the liver, in the absence and presence of a magnetic field, which indicates its metabolic pathway. The intensity of the fluorescence in the animals’ livers did not change over time, although an increase in fluorescence in the tumour was observed in the presence of a magnetic field.Conclusion: This type of MNP, used in combination with a magnetic field of calculated strength, can form the basis for the development of magnetically controlled transport of cytostatic drugs into tumour tissue.Keywords: fluorescence analysis, indocyanine, iron oxide nanoparticles, magnetically controlled delivery of cytostatics, tumor targeting

Distilled spirits production using Saccharomyces cerevisiae requires understanding of the mechanisms of yeast cell response to alcohol stress. Reportedly, specific mutations in genes of the ubiquitin-proteasome system, e.g., RPN4, may result in strains exhibiting hyper-resistance to different alcohols. To study the Rpn4-dependent yeast response to short-term ethanol exposure, we performed a comparative analysis of the wild-type (WT) strain, strain with RPN4 gene deletion (rpn4-Δ), and a mutant strain with decreased proteasome activity and consequent Rpn4 accumulation due to PRE1 deregulation (YPL). The stress resistance tests demonstrated an increased sensitivity of mutant strains to ethanol compared with WT. Comparative proteomics analysis revealed significant differences in molecular responses to ethanol between these strains. GO analysis of proteins upregulated in WT showed enrichments represented by oxidative and heat responses, protein folding/unfolding, and protein degradation. Enrichment of at least one of these responses was not observed in the mutant strains. Moreover, activity of autophagy was not increased in the RPN4 deletion strain upon ethanol stress which agrees with changes in mRNA levels of ATG7 and PRB1 genes of the autophagy system. Activity of the autophagic system was clearly induced and accompanied with PRB1 overexpression in the YPL strain upon ethanol stress. We demonstrated that Rpn4 stabilization contributes to the PRB1 upregulation. CRISPR-Cas9-mediated repression of PACE-core Rpn4 binding sites in the PRB1 promoter inhibits PRB1 induction in the YPL strain upon ethanol treatment and results in YPL hypersensitivity to ethanol. Our data suggest that Rpn4 affects the autophagic system activity upon ethanol stress through the PRB1 regulation. These findings can be a basis for creating genetically modified yeast strains resistant to high levels of alcohol, being further used for fermentation in ethanol production.

Objective of the studywas the development of experimental ELISA tests and lateral flow immunoassays for detection of staphylococcal enterotoxins, A and B types.Materials and methods. Hybridomas, producing monoclonal antibodies against staphylococcal enterotoxins A and B from State Collection of the Affiliated Branch of the “48th Central Research Institute” of the Ministry of Defense of the Russian Federation, BALB/c mice and staphylococcal enterotoxins A and B were used in the research. Hybridoma cells were incubated in culture flasks and in the peritoneal cavity of BALB/c mice. Monoclonal antibodies were isolated from ascitic fluids through precipitation with saturated ammonium sulfate subsequently purified using ion-exchange chromatography. Obtained preparations of monoclonal antibodies were used for the construction of ELISA tests and immune-chromatographic reagent panels for the detection of staphylococcal enterotoxins A and B. Specific components of ELISA tests were lyophilized in protective media.Results and discussion. ELISA tests and lateral flow immunoassays which allow for detecting staphylococcal enterotoxins A and B at concentrations of 0.5 ng/ml and higher, including in food samples, have been constructed.

Objective. To present the clinical and functional results of combined treatment of the complications of long-term silicone oil tamponade in a patient with retinopathy of premature. Materials and methods. A 24-year-old patient diagnosed with stage 4b retinopathy of premature in a single seeing right eye. Between 2011 and 2020 underwent 5 microinvasive revisions of the vitreous cavity with replacement of silicone oil and median duration of silicone oil tamponade of 19+25.5 months over this entire period. Because of the constant migration of emulsified silicone oil to anterior chamber due to weakness of iridolenticular ligaments, band keratopathy developed in the right eye, opacity of the IOL due to the adhesion of precipitates on its anterior and posterior surfaces, pupillary membrane, and aggravation of the proliferative membrane on the ocular surface. UCVA was proectio incerta and IOP was 17 mmHg. The median thickness of the cornea was 853 μm, the average thickness of the corneal calcifications is 57 μm. The patient underwent revision of the vitreous cavity with removal of the pupillary membrane, the next steps were to install bandage sutures in the anterior chamber parallel to iris in two mutually perpendicular surfaces to create additional barriers to silicone oil migration. Then we used 27 mg of K3-EDTA to produce 0.1% chelating solution and to remove corneal calcium deposits. Final stage was YAG – laser discision of precipitates from the IOL surfaces. Results. Postoperatively UCVA of the right eye in 1-month was 0.05, IOP was 17 mmHg and endothelial cell density was 1200 cells / mm2. According to OCT data the median corneal thickness was 640 μm, the thickness of the epithelial layer was 39 μm. Biomicroscopically, cornea was transparent, a single silicone oil vesicle in the lower segment of anterior chamver, the bandage sutures are consistent, the IOL is centered with a transparent optical zone, silicone oil visualized on the fundus, epi- and subretinal proliferates were delimited by laser coagulates, epiretinal membrane was in the macular region. Key words: retinopathy of prematurity, silicone oil, emulsification, ribbon-like keratopathy, bandage threads, EDTA.

This article presents the first experimental data on the ability of microbial communities from sediments of the Gorevoy Utes natural oil seep to degrade petroleum hydrocarbons under anaerobic conditions. Like in marine ecosystems associated with oil discharge, available electron acceptors, in particular sulfate ions, affect the composition of the microbial community and the degree of hydrocarbon conversion. The cultivation of the surface sediments under sulfate-reducing conditions led to the formation of a more diverse bacterial community and greater loss of n-alkanes (28%) in comparison to methanogenic conditions (6%). Microbial communities of both surface and deep sediments are more oriented to degrade polycyclic aromatic hydrocarbons (PAHs), to which the degree of the PAH conversion testifies (up to 46%) irrespective of the present electron acceptors. Microorganisms with the uncultured closest homologues from thermal habitats, sediments of mud volcanoes, and environments contaminated with hydrocarbons mainly represented microbial communities of enrichment cultures. The members of the phyla Firmicutes, Chloroflexi, and Caldiserica (OP5), as well as the class Deltaproteobacteria and Methanomicrobia, were mostly found in enrichment cultures. The influence of gas-saturated fluids may be responsible for the presence in the bacterial 16S rRNA gene libraries of the sequences of "rare taxa": Planctomycetes, Ca. Atribacteria (OP9), Ca. Armatimonadetes (OP10), Ca. Latescibacteria (WS3), Ca. division (AC1), Ca. division (OP11), and Ca. Parcubacteria (OD1), which can be involved in hydrocarbon oxidation.

The ignition and combustion of anthracite modified by the addition of pyrolysis oil obtained during thermal processing of waste car tires (WCTs) had been studied. The mass fraction of WCT pyrolysis oil was varied in the range from 5 to 30 wt %. The additive was applied by the drop impregnation method. Ignition and combustion of obtained samples were carried out in a combustion chamber at temperatures of the heating medium Tg = 600-800 °C. The gas-phase combustion products were analyzed using an in-line gas analyzer. The application of WCT pyrolysis oil as a combustion modifier contributed to an increase in the reactivity of anthracite, which was expressed in a decrease in the minimum ignition temperature (by 23-104 °C) and a reduction in the ignition delay time. The high-speed video recording indicated that the combustion of both initial and modified with 5 wt % pyrolysis oil anthracite samples was realized in oxidation mode. For samples with more than 10 wt % pyrolysis oil additive, the formation of a visible flame was observed near the sample surface. With an increase in the mass fraction of the additive, the rate of combustion front propagation was increased. The application of WCT pyrolysis oil as a combustion modifier also contributed to the reduction or even the almost complete elimination of unburnt carbon content in the ash residue formed after anthracite combustion.

We have studied the spontaneous comminution of cast materials consisting of a Mn-doped Cr2AlC MAX phase and chromium, manganese, and aluminum carbides and aluminides. The materials were prepared in the form of ingots by self-propagating high-temperature synthesis (SHS) in a 3-L reactor at an argon pressure p = 5 MPa. The starting mixtures consisted of manganese(IV) oxide, chromium(III) oxide, aluminum (ASD-1), and carbon. The presence of aluminum carbide (Al4C3) in a cast material has been shown to lead to spontaneous comminution of the cast material (without mechanical or chemical influences) into powders with a crystalline particle size under 100 μm. The particle size reduction has been shown to result from reaction between aluminum carbide and atmospheric moisture. The synthesized materials have been characterized by X-ray diffraction and X-ray microanalysis, and we have studied structural and phase states of particles of the desired products obtained as a result of self-comminution of a cast SHS material.

Plant fibers constitute a major part of renewable biomass and are a valuable resource for various industries, composite material chemistry, and bioconversion processes. Plant fibers are specialized long cells with thick cell walls that are a convenient model for investigating fundamental issues such as individual cell biogenesis, cell wall formation, and cell specialization. Plant fibers usually accumulate secondary cell walls, which contain lignin, cellulose, and hemicelluloses like xylan, and are laid over thin primary cell walls.

The paper presents the results of research aimed at the fatigue evaluation of airframe elements made of aluminum alloys damaged by corrosion. Fatigue tests of the samples and metallographic studies were performed. The results of multi-year research on the effect of corrosion damage on the fatigue performance of aluminum alloys were summarized, and an observed dependence was established between the corrosion damage parameter and the material characteristics.

Multilayer graphene oxide was synthesized by anodic oxidation of dispersed graphite, and the efficiency of its use as an electrode material for a supercapacitor was shown. In an alcohol suspension, the thickness of multilayer graphene oxide particles is less than 0.1 μm with an area of more than 100 μm2. The multilayer graphene oxide electrode has a high specific capacity of 107 F g–1 and a high charge retention rate of 97% after 5000 cycles at a current of 2 A g–1. The multilayer graphene oxide electrode demonstrated a maximum specific energy of 8.7 W h kg–1 at a current density of 0.1 A g–1 and a maximum power of 2291.1 W kg–1 at a current density of 4 A g–1. The impedance data at various DC voltages showed that after 5000 cycles, the charge transfer resistance increases by 26%. It was found that multilayer graphene oxide synthesized by the electrochemical method is a promising electrode material for producing a symmetric supercapacitor.

A material based on a (VCr)2AlC solid solution has been obtained for the first time by self-propagating high-temperature synthesis from a powder reaction mixture of vanadium(V) and chromium(III) oxides with aluminum and carbon (graphite). The synthesized material has been studied by X-ray diffraction and microstructural analyses. It has been shown that the product also contains vanadium and chromium carbides and intermetallics. The presence of these phases seems to be associated with the nonequilibrium character of the synthesis process due to a short “lifetime” of melt and its fast cooling and crystallization. The synthesized material is an electrical conductor, which demonstrates a metallic character of conductivity throughout the entire measured temperature range of 300–1300 K. The room-temperature specific resistance of the composite material based on a (Cr,V)2AlC solid solution is 1.14 µΩ m, which is higher than the specific resistance of the materials based on the Cr2AlC and V2AlC MAX phases. The microhardness of the synthesized material is 6.9 GPa.

The article investigates the influence of the reduction modes of hollow nickel oxide microspheres synthesized by the pyrolysis of ultrasonic aerosols on the ratio of the oxide and metallic forms of nickel in their structure. The synthesis of microspheres from an aerosol of an aqueous solution of nickel nitrate was carried out; their composition and morphology were studied. The reduction of microspheres was carried out in a stream of hydrogen at different temperatures. The ratio of metallic nickel and oxide was determined by two different methods: according to the data of thermogravimetric analysis and by the Rietveld method based on the results of x-ray phase analysis. It is shown that the proportion of metallic nickel increases with an increase in the reduction temperature to approximately 375°C and then changes insignificantly. The fractional composition of microspheres was determined.

Possibility of determination of the fragments and articles made of different grades of steel aluminium and copper alloys and their affiliation to the common melt was examined via the methods of photoelectric spectral analysis based on composition of micro-impurities. Chemical elements with micro-impurities were revealed; they allow to determine affiliation of metal fragments to one melt. Ultimately possible deviations of micro-impurities within one melt were obtained. The technique allowing to establish affiliation of fragments to the common melt based on their elementary composition of micro-impurities with minimal amount of measurements was suggested based on the obtained results. The minimal geometric size of a sample available for analysis was determined; it allows to classify the examined fragments to one melt based on the results of investigation of expanded elementary composition of micro-impurities. Practical opportunities of this technique were displayed on the example of the alloys with different chemical composition.

The hollandite-like copper doped potassium titanate was synthesized by two-step method, including the potassium polytitanate precursor modification with copper compounds in aqueous solution and the following calcination at 900 °C. The structure of material obtained was studied using the XRD and SEM analysis. The Rietveld method was used to estimate the crystalline unit cell parameters and calculate the exact stoichiometry of K1.53(Cu0.76Ti7.24)O16 by refining the atomic occupancies for chemical elements. High-k ceramic materials based on this shollandite-like solid solution were sintered at different temperatures varied in the range from 1000 to 1100 °C. The influence of sintering conditions on electric properties of the obtained ceramics was investigated in a wide frequency range. The contribution of different processes on permittivity was discussed using the electron-pinned defect-dipole (EPDD) model, and the internal barrier layer capacitance (IBLC) model. The optimal conditions to produce modified potassium polytitanate, used as intermediate, as well as optimal sintering conditions which allowed obtaining mono-phase hollandite-like ceramic materials were recognized. It was found that such ceramic materials had high permittivity (e’ ≈ 0.9 × 104 at 10 Hz).

High-temperature synthesis of cast composite materials in the Cr–Mn–Al–C system with various ratios between the Cr2AlC MAX phase and chromium and manganese aluminides and carbides was studied. Experiments were performed in a universal 3-L reactor under argon pressure Р = 5 MPa. Mixtures of powders of chromium(III) and manganese(II, IV) oxides and calcium peroxide with aluminum (ASD-I) and carbon were used as a charge. The synthesis features and the phase composition and microstructure of the target products are significantly influenced by the reactant ratio in the charge. At the stoichiometric ratio of the components corresponding to the Cr2AlC phase, a cast composite material consisting of the Cr2AlC MAX phase, chromium carbides Cr7C3 and Cr3C2, and chromium aluminide Cr5Al8 is formed. In the course of combustion of the charge with the component ratio corresponding to the Mn2AlC phase, a cast composite material consisting of manganese carbides (Mn3AlC, Mn0.545Al0.42C0.035) and aluminide (MnAl) is formed. When these compositions are combined in an 0.75 : 0.25 ratio, the final product is a composite material consisting of a solid solution based on the Cr2AlC MAX phase, manganese carbides (Mn3AlC), and chromium aluminides (Cr2Al). When these compositions are combined in an 0.5 : 0.5 ratio, the final product is a composite material consisting of the manganese-doped Cr2AlC MAX phase and of manganese (Mn14Al86, Mn22.5Al77.5) and chromium (Cr5Al8) aluminides. The final products were characterized by X-ray diffraction and local microstructural analysis.

The effect of the dilution of a synthesis gas with nitrogen on the activity, selectivity and productivity of a Fischer–Tropsch reactor with a fixed bed of granular catalyst during synthesis on a pilot plant of a full cycle for the conversion of natural gas into synthetic oil is studied experimentally. Experimental data are presented that were obtained at different contents of nitrogen in the synthesis gas: up to 2, 50, and 70%. Analysis of the experimental data shows that diluting the synthesis gas contributes to an increase in the selectivity to C5+, and a decrease in the selectivity to methane. A drop in the reactor’s productivity observed upon the dilution of synthesis gas can be compensated for by increasing the consumption of synthesis gas. The negative effect of decrease in the pressure of FT synthesis from 2 to 1.5 and 1.0 MPa on the catalytic FT synthesis performed on a twice-diluted synthesis gas at a synthesis gas space velocity of 4000 h–1 is demonstrated.

Hepatitis B surface antigen (HBsAg) is the most clinically relevant serological marker of hepatitis B virus (HBV) infection. Its detection in blood is extremely important for identification of asymptomatic individuals or chronic HBV carriers, screening blood donors, and early seroconversion. Rapid point-of-care HBsAg tests are predominantly qualitative, and their analytical sensitivity does not meet the requirements of regulatory agencies. We present a highly sensitive lateral flow assay based on superparamagnetic nanoparticles for rapid quantification (within 30 min) of polyvalent HBsAg in serum. The demonstrated limit of detection (LOD) of 80 pg mL-1 in human serum is better than both the FDA recommendations for HBsAg assays (which is 0.5 ng mL-1) and the sensitivity of traditional laboratory-based methods such as enzyme linked immunosorbent assays. Along with the attractive LOD at lower concentrations and the wide linear dynamic range of more than 2.5 orders, the assay features rapidity, user-friendliness, on-site operation and effective performance in the complex biological medium. These are due to the combination of the immunochromatographic approach with a highly sensitive electronic registration of superparamagnetic nanolabels over the entire volume of a 3D test structure by their non-linear magnetization and selection of optimal antibodies by original optical label-free methods. The developed cost-efficient bioanalytical technology can be used in many socially important fields such as out-of-lab screening and diagnosis of HBV infection at a point-of-demand, especially in hard-to-reach or sparsely populated areas, as well as highly endemic regions.

COVID-19 respiratory disease caused by the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) has rapidly become a global health issue since it emerged in December 2019. While great global efforts are underway to develop vaccines and to discover or repurpose therapeutic agents for this disease, as of this writing only the nucleoside drug remdesivir has been approved under Emergency Use Authorization to treat COVID-19. The RNA-dependent RNA polymerase (RdRP), a viral enzyme for viral RNA replication in host cells, is one of the most intriguing and promising drug targets for SARS-CoV-2 drug development. Because RdRP is a viral enzyme with no host cell homologs, selective SARS-CoV-2 RdRP inhibitors can be developed that have improved potency and fewer off-target effects against human host proteins and thus are safer and more effective therapeutics for treating COVID-19. This review focuses on biochemical enzyme and cell-based assays for RdRPs that could be used in high-throughput screening to discover new and repurposed drugs against SARS-CoV-2.

Local resistive switching in a contact between the probe of an atomic force microscope (AFM) and ZrO2(Y) films (including with a Ta2O5 sublayer) on conducting substrates has been studied. Switching has been initiated by triangular voltage pulses on which an rf sine-wave signal was imposed. The dependence of the difference between currents through the AFM probe in low- and high-ohmic states of dielectric films on the frequency of the rf sine-wave signal exhibits maxima at characteristic frequencies corresponding to hops of O2– ions between oxygen vacancies in ZrO2(Y) and Ta2O5 at 300 K. This effect is related to the resonance activation of O2– ion migration over oxygen vacancies by an external rf electric field.

Three-body continuum p-p-α for the charge exchange reaction 1H(6Li,6Be)n is studied in detail. The data are obtained with a high volume of statistics (approximately 4.7 million events), making it possible to analyze three-particle correlations. Detailed information about the structure of 6Ве and the reaction is obtained as a result.

Highlighted are the protein properties determining protein binding to the silver nanoparticle surface., Nanoparticles (NPs) in contact with protein-containing media such as biological fluids rapidly acquire a surface layer of proteins, known as the protein corona. The protein composition and structural properties of the protein corona are crucial for NP interactions with living cells. Although much has been learned about the protein corona phenomenon, further elucidation could benefit from extensive quantitative proteomics analysis. Herein we report a comprehensive quantitative characterization (>350 proteins) of the corona that formed on 60 nm silver NPs via interaction with human blood plasma, as a function of pH and temperature. By varying the pH and temperature one can access different conformational spaces and charge localizations of the plasma proteins, which in turn provide knowledge pertinent to how the proteome corresponds to binding affinity. Thirty-eight percent of the quantified proteins bind at all temperatures, 47% at all pH values, and of these most persistent proteins, approximately 60% do not significantly change in abundance within the protein corona. Evaluation of 544 protein properties (present in the Kyoto databank) suggests that binding of these proteins to NPs is determined by the extent of hydrophobicity, β-sheet propensity, α-helical structure (and turns), and amino acid composition. Protein binding is promoted by a larger amount of β-sheets, higher hydrophobicity, and a smaller amount of α-helices. Our work enhances researchers' knowledge of a long-standing, vexing aspect of the nano–bio interface.

It is shown that self-forming GeSi nanoislands built into the dielectric–semiconductor interface in the Si(001)-based metal–oxide–semiconductor (MOS) structures with the SiOx and ZrO2(Y) dielectric layers obtained by magnetron sputtering initiate bipolar resistive switching without preliminary electroforming. The I–V characteristics and electrical parameters of the MOS structures in the high- and low-resistance states have been investigated. The change in the charge incorporated in the dielectric at the dielectric–semiconductor interface during resistive switching has been established, which is related to the formation and destruction of conducting filaments. The optically stimulated switching of the MOS structures with the ZrO2(Y) dielectric layer from the high- to low-resistance state has been observed, which is caused by an increase in the conductivity of the space charge region in the Si substrate due to the interband optical absorption in Si leading to the voltage redistribution between Si and ZrO2(Y). A difference between the shapes of the low-signal photovoltage spectra of the MOS structures in the spectral region of the Si intrinsic photosensitivity in the high- and low-resistance states related to the leakage of photoexcited carriers from Si into a metal electrode through filaments has been found.

One of the main directions for the attainment of high-performance solid oxide electrochemical cells, including those based on proton-conducting electrolytes, consists in the rational engineering of functional materials. Herein, we examine the use of Nd2–xBaxNiO4+δ (NBNx, 0 ≤ x ≤ 0.4) materials as potential oxygen electrodes for protonic ceramic fuel cells (PCFCs) based on conventional Ba(Ce,Zr)O3-electrolytes. A Ba-doping strategy is proposed for Nd2NiO4+δ for reducing chemical interdiffusion of barium-ions from electrolyte to electrode during long-term operation. It is experimentally confirmed that a moderate Ba-content is beneficial in terms of reducing the quantity of impurity phases formed at the NBNx/Ba(Ce,Zr)O3 interface during deliberately-imposed extreme temperature conditions (1250 °C for 20 h). In addition, materials with x = 0.1 and 0.2 exhibit the highest electrical conductivity with no adverse effects on their thermomechanical properties. Thus, when characterising symmetrical cells in wet air conditions, NBN0.1 and NBN0.2 electrodes demonstrates lower polarisation resistances (down to 1.7 Ω cm2 at 700 °C) compared with NBN0, NBN0.3 and NBN0.4 electrodes. Based on these findings, the Ba-doping of nickelates can be recommended as a promising modification for the design of electrodes having good performance and chemical compatibility.

The effect of syngas dilution with nitrogen on the activity, selectivity and capacity of the Fischer–Tropsch reactor with a fixed granulated catalyst bed was studied during the synthesis at the integrated pilot plant for conversion of natural gas to syncrude. Experimental data were obtained at different nitrogen content in syngas: up to 2, 50 and 70 %. The analysis of experimental data shows that the dilution of syngas increases the selectivity to C5+ and decreases the selectivity to methane. The decrease in the reactor capacity observed upon dilution of syngas can be compensated by increasing the syngas flow rate. A decrease in the pressure of the Fischer–Tropsch synthesis from 2 to 1.5 and 1.0 MPa was shown to exert a detrimental effect on the catalytic performance of the process carried out with a twofold dilution of syngas at its hourly space velocity of 4000 h–1.