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The joint efforts of chemists, physicians and technologists conducting researches to create new medical sorbents and combined drugs based on nanosilica, which have not only a detoxifying effect, but also antibacterial, wound healing, hemostatic and other important properties. One of the stages of such a research is developing regulatory documentation. To control the quality of the sorbent, the method of point measurements is most often used, according to it, the amount of adsorption of the marker substance at the single point of the adsorption curve is determined. The suitability of sorbents based on nanosilicа for using is determined by the value of the adsorption capacity concerning to medical gelatin. No other requirements for the process of test adsorption of gelatin by the sorbent are given. although it is known that the adsorption of proteins depends on the pH of the solution. Its maximum value is reached at a pH value corresponding to the isoelectric point (pI) of the protein. Each protein can be characterized by its own isoelectric point. Domestic and foreign standards give only the value of “pH of aqueous solutions” of gelatin and do not contain the indicator “isoelectric point”. The aim of the work is to study the influence of the isoelectric point of gelatin on its adsorption on nanosilica surface at different pH to appreciate the suitability of conditions for determining the adsorption activity of medical sorbents based on nanosilica. The adsorption of three samples of gelatin was examined in the work: A – edible gelatin (pI = 4.3–4.8); B – that from the catalog “Merck” (pI = 4.3–4.8) and C – that from the catalog “Fluka” (pI = 7.5–7.7) on nanosilica surface in the pH range from 3 to 8. It has been shown that for samples A and B the dependence has a maximum at pH ~ 4.5–5; and for sample C, the adsorption increases monotonically with increasing pH. It was noted that at pH ~ 5 the adsorption values for all gelatin samples were approximately equal. The adsorption activity of nanosilica concerning to proteins determined from the isotherms and the method of point measurements is compared. It has been found that the adsorption value of gelatin A onto the nanosilica at C initial = 700 mg/100 ml is equal to the A ave value determined by the Langmuir isotherms. This fact verifies the applicability of the method of point measurements for nanosilica/gelatin system to characterize the pharmacological activity of nanosilica based sorbents.

Acetylene and ethylene are the smallest molecules that contain an unsaturated carbon–carbon bond and can be efficiently utilized in a large variety of cycloaddition reactions. In this review, we summarize the application of these C2 molecular units in cycloaddition chemistry and highlight their amazing synthetic opportunities.1 Introduction2 Fundamental Features and Differences of Cycloaddition Reactions Involving Acetylene and Ethylene3 (2+1) Cycloaddition4 [2+2] Cycloaddition5 (3+2) Cycloaddition6 [4+2] Cycloaddition7 (2+2+1) Cycloaddition8 [2+2+2] Cycloaddition9 The Use of Acetylene and Ethylene Cycloaddition for Deuterium and 13C Labeling10 Conclusions

The effects of water deficiency (–0.3 MPa) on plant growth, the water and proline content, fluorescence parameters chlorophyll PSI and II, and CO2/H2O gas exchange in plant leaves were studied in two populations of xero-halophyte Atriplex tatarica L. (C4 NAD-ME) with contrasting productivity. Based on growth parameter analysis, a less-productive population (P1) was more tolerant of osmotic stress, and a more-productive population (P2) was less tolerant. The studied populations demonstrated different ways of maintaining the water balance in leaves. P1 was characterised by an insensitivity of its stomatal apparatus, a significant decrease in water potential of mesophyll cells’ apoplast in substomatal cavity, an increase in proline content, and activation of PSI cyclic electron transport in leaves. In P2, maintaining the water content in leaves under stress conditions was achieved by stomatal closure. The impact of stress was manifested by decreased intensity of photosynthesis, transpiration, PSII efficiency and more intensified of dark respiration in P2. Thus, various ways by which to maintain the water balance in plant leaves in two populations were revealed under weak osmotic stress.

Introduction. It is the recommendations for treatment of sepsis and septic shock combined with rheumatologists’ recommendations for monoclonal antibodies therapy that guide severe COVID-19 management in ICU. However, those recommendations may not be fully applied to patients with acute respiratory distress-syndrome associated with SARS-CoV-2, as there exists a difference in pathogenesis between sepsis and virus-associated pneumonias. Monoclonal antibodies therapy may contribute to cytokine cascade severity and promote lung injury. Cytokine storm aggravates the course of the disease. At present, there are two groups of methods described in literature for cytokine storm control and therapy: pharmacological and extracorporeal approaches.Materials and methods. We have performed a retrospective analysis of five COVID-19 patients with acute respiratory syndrome. Cytokine adsorption start criteria were respiratory insufficiency and IL-6 levels greater than 500 pg/ml. Adsorption therapy was initiated within 24 hours of ICU admission and continued for 48–120 hours in hemoperfusion mode on Multifiltrate machine (Fresenius Medical Care). The length of a single session of CytoSorb (Cytosorbents Inc.) therapy was 24 hours.Results. All patients demonstrated SpO2/FiO2 ratio growth and IL-6 concentration decrease by the end of hemoadsorption. We noted lymphocyte count rise as well as IgM и IgG SARS-CoV-2 antibodies titer substantial increase.Conclusions. Our observations suggest that the early start of hemoadsorption associates with gas-exchange stabilization and hinders respiratory distress progression. Hemoadsorption allows for pro-inflammatory cytokines concentrations decrease and prevents secondary lung injury. According to our data, hemoadsorption is beneficial to form a coronavirus infection specific immune response. Further research is needed for a detailed study of the results we here describe.

Nowadays, the technical advances call for efficient electromagnetic interference (EMI) shielding of transparent devices which may be subject to data theft. We developed Cu–Ag and Ni–Ag meshes on flexible PET substrate for highly efficiency transparent EMI shielding coating. Cu–Ag and Ni–Ag meshes obtained with galvanic deposition of copper and nickel on thin Ag seed mesh which was made by cracked template method. Coefficients S11, S21 and shielding efficiency (SE) were measured for Cu–Ag and Ni–Ag meshes in X-band (8–12 GHz) and K-band (18–26.5 GHz). 90 s copper deposition increase SE from 23.2 to 43.7 dB at 8 GHz with a transparency of 82.2% and a sheet resistance of 0.25 Ω/sq. The achieved maximum SE was 47.6 dB for Cu–Ag mesh with 67.8% transparency and 41.1 dB for Ni–Ag mesh with 77.8% transparency. Cu–Ag and Ni–Ag meshes have high bending and long-term stability. Minimum bend radius is lower than 100 µm. This effect allows to produce different forms of transparent shielding objects, for example, origami method. Our coatings are the leading among all literary solutions in three-dimensional coordinates: of sheet resistance–optical transmittance–cost of produced.

The lipid and fatty acid content of benthopelagic scavenging amphipods Ommatogammarus flavus and O. albinus from different depths of Lake Baikal were studied. These amphipods, known to move across a wide range of depths in Lake Baikal, had a relatively high level of total lipids (up to 46% dry weight) in comparison to other aquatic amphipods. This high level of total lipids resulted from a high concentration of storage lipids (triacylglycerols). The monounsaturated 18:1(n-9) acid in combination with 16:1(n-7), and 18:1(n-7) fatty acids were dominant in the amphipods, reflecting their deep-dwelling scavenging mode of life. Local groups of amphipods were distinguished along a Lake Baikal depth gradient based on the primarily diet-associated differences in fatty acid composition.

The technique that enables simultaneous evaluation of water potential in the substomatal cavity of the intact leaf (ψwа) and rate of its photosynthetic CO2/H2O gas exchange was applied to a halophyte Suaeda altissima (L.) Pall. Formation of a water-potential gradient in a whole plant, rate of CO2 uptake, rate of transpiration, and concentrations of Na+ and Cl– ions in the plant organs were determined under conditions of chloride–sodium salinization of a nutrient solution. It was found that the salinization decreases not only biological productivity of the plants but also their capacity to accumulate Cl– in the amounts equivalent to Na+ accumulation. High salinity also diminished the gradient of water potential between a nutrient solution and the apoplast of the cells in the leaf substomatal cavity due to the increase in ψwа and, respectively, decrease in the water stream from roots to leaves and the rate of CO2/H2O gas exchange of the leaf. It was shown that the decrease in the water potential in the interface between liquid and gaseous phases in the apoplast of the substomatal cavity (expressed in the ψwа value) plays an essential role in the regulation of water uptake under salinization conditions. It is supposed that the NaCl-induced increase in ψwа is a consequence of the suppression of photosynthesis and a resultant osmolyte shortage together with the decrease in plant productivity due to the stress impact exerted by NaCl.

U46619, a synthetic analogue of thromboxane A2 was used for modeling acute stable and reversible pulmonary arterial hypertension. Administration of U46619 in high doses led to vascular collapse and inhibition of cardiac function. The doses of U46619 were empirically selected that allow attaining the target level of pulmonary hypertension without systemic hemodynamic disturbances. The possibility of attaining the target level of pulmonary hypertension and reversibility of changes after termination of U46619 infusion make this model attractive for evaluation of the efficiency of different therapeutic methods of treatment of pulmonary hypertension in large animals.

Immune thrombocytopenia (ITP) is believed to be associated with platelet function defects. However, their mechanisms are poorly understood, in particular with regard to differences between ITP phases, patient age, and therapy. We investigated platelet function and bleeding in children with either persistent or chronic ITP, with or without romiplostim therapy. The study included 151 children with ITP, of whom 56 had disease duration less than 12 months (grouped together as acute/persistent) and 95 were chronic. Samples of 57 healthy children were used as controls, while 5 patients with leukemia, 5 with aplastic anemia, 4 with MYH9-associated thrombocytopenia, and 7 with Wiskott-Aldrich syndrome were used as non-ITP thrombocytopenia controls. Whole blood flow cytometry revealed that platelets in both acute/persistent and chronic ITP were increased in size compared with healthy donors. They were also pre-activated as assessed by PAC1, CD62p, cytosolic calcium, and procoagulant platelet levels. This pattern was not observed in other childhood thrombocytopenias. Pre-activation by CD62p was higher in the bleeding group in the chronic ITP cohort only. Romiplostim treatment decreased size and pre-activation of the patient platelets, but not calcium. Our data suggest that increased size, pre-activation, and cytosolic calcium are common for all ITP platelets, but their association with bleeding could depend on the disease phase.

The effect of high-pressure-jet (HPJ) processing (0–500 MPa) on low-fat (6% fat) ice cream was studied by evaluating physiochemical properties before freezing, during dynamic freezing, and after hardening. An HPJ treatment ≥400 MPa decreased the density, increased the apparent size of colloidal particles, and altered rheological behavior (increased non-Newtonian behavior and consistency coefficients) of low-fat ice cream mix before freezing. During dynamic freezing, the particle size and consistency coefficient decreased but remained higher in 400 MPa–treated samples vs. non-HPJ-treated controls at the conclusion of freezing. The resulting ice creams (400 and 500 MPa–treated) had similar hardness values (3,372 ± 25 and 3,825 ± 14 g) and increased melting rates (2.91 ± 0.13 and 2.61 ± 0.31 g/min) compared with a control sample containing polysorbate 80 (3,887 ± 2 and 1.62 ± 0.25 g/min). Visualization of ice cream samples using transmission electron microscopy provided evidence of casein micelle and fat droplet disruption by HPJ treatment ≥400 MPa. In the 400 MPa–treated samples, a unique microstructure consisting of dispersed protein congregated around coalesced fat globules likely contributed to the altered physiochemical properties of this ice cream. High-pressure-jet processing can alter the microstructure, rheological properties, and hardness of a low-fat ice cream, and further modification of the formulation and processing parameters may allow the development of products with enhanced properties.

In the work, sedimentation-stable sols of indium (III) and tin (IV) hydroxides were obtained by the Anion Resin Exchange Precipitation, which consists of the exchange reaction between the OH ions of the anion exchange resin and the anions of metal-containing solutions. The synthesized hydrosols were used to obtain conducting films of indium (III) In2O3 oxide and indium oxide doped with Tin In2O3: Sn, with a surface resistance of 4 kOhm/sq, thicknesses of 200–500 nm and a transparency of more than 85 %. The modes of applying precursors to glass substrates by the modified spray method and centrifugation method are selected. Films were studied using XRD, SEM, optical microscopy and spectrophotometry

We report on results of investigation into the structure of a plasma jet generated by a coaxial plasma accelerator with conical insert in the discharge formation region. Using high-speed optoelectronic camera, we detected an inhomogeneous structure of glowing fractions of argon and deuterium jets. It was found that the jet radiation intensity oscillates with a characteristic frequency of 0.3–0.9 MHz. The argon plasma jet consisted of fragments diverging from the axis; plasma recombined 20 μs after the beginning of the discharge. The deuterium plasma jet resembled flakes. Its radiation intensity decreased significantly by 8 μs. The characteristic frequencies of radiation nonuniformities on the jet axis were about 0.09 cm–1 for argon and 0.3 cm–1 for deuterium. Analysis of the behavior of the discharge in the plasma accelerator revealed that a diffuse discharge was initiated at the base of the conical insert. After 0.5 μs, the discharge emerged at the outer boundary of the insert, was contracted, and occurred between central and external electrodes. The emergence of the discharge from the accelerator was observed 3 μs later and was accompanied with a glow of the end face of the central electrode. In the measurements of temperature of the lateral surface of external electrode using an infrared camera, it was found that heating is localized near the edge of conical insert and at the outlet of the accelerator. Results of investigations can be used for gas ionization, material irradiation, and simulation of interaction of plasma flows with the magnetic field in the outer space in laboratory conditions.

Anticancer hybrid mineral highly-magnetic protein–tannin vehicles are tunable and controllable external triggers for drug delivery systems. The saturation level of submicron particles of calcium carbonate with magnetic nanoparticles was achieved. The Brillouin light scattering technique and the movement determination of composites in the non-uniform magnetic field, as well as the SEM study of hybrid mineral highly-magnetic composites, made it possible to characterize the magnetic properties of the carriers and determine that 3 freezing/thawing cycles of magnetic nanoparticles are sufficient to obtain an optimal drug carrier. We have demonstrated that doxorubicin and mitoxantrone are effectively encapsulated in vehicles, while the encapsulated drugs are effectively stored in clean water and PBS. Anticancer hybrid mineral highly-magnetic protein–tannin vehicles have a higher cytostatic effect on MCF-7 breast cancer cells because of the best interaction of the cytostatics with DNA due to the inside-out structure compared with the NMUMG breast healthy cell line. Extra magnetic anticancer structures of the core–shell can be potentially used as objects for preserving antitumor drugs over time, due to the higher survival rate compared to the pure substance and the lack of release of antitumor drugs into model fluids.

Isavuconazole (ISV) is a systemic antifungal agent which is used to treat invasive aspergillosis, mucormicosis and candidiasis. Although both oral and intravenous dosage forms of this drug exist on the market, the crystal structure and physicochemical properties of ISV as well as possible alternative solid forms are yet unexplored in the literature. In the present work, the solid form landscape of isavuconazole including solvate, polymorph and salt screening was studied systematically. The solid-state properties of initial crystalline ISV and newly obtained forms (ISV monohydrate, two amorphous forms obtained by different means and two pharmaceutical salts with p-toluenesulfonic and phosphoric acids) were described for the first time. The structures of all crystalline forms were solved based on the single crystal X-Ray diffraction data, and the packing forces in the considered solids were studied using different theoretical approaches. The transformation pathways between the ISV solid forms were investigated experimentally and rationalized based on the DFT computations and non-covalent interaction analysis. It was observed that crystalline isavuconazole does not transform into the hydrate upon dissolution, in contrast to other solid forms. The amorphous and salt forms of ISV were found to demonstrate a spring-like increase of the drug concentration in pharmaceutically relevant buffer media. The tableting of the pharmaceutical salts leads to slower phase transformation into the ISV hydrate and prolonged drug supersaturation.

The lithium-doped phases Gd1.7Li0.3Zr2O6.7 and Gd2Zr1.7Li0.3O6.55 with a pyrochlore structure were prepared by the modified Pechini method using citric acid and glycerol. Monitoring of the lithium content by using a nuclear microanalysis showed that a significant loss of lithium occurred after heat treatment above 1200 °C. Dense ceramics with a stoichiometric lithium content can be prepared by a low temperature microwave sintering (1100 °C). The introduction of lithium in the Gd-sublattice was accompanied by a decrease in the unit cell parameter (a = 10.5208 (1) A vs 10.5346 (2) A for Gd2Zr2O7) and during doping at the Zr-sites with lithium, the cell parameter increased (10.5720 (1) A). The doping in both cases led to an increase in the free cell volume. The impedance spectroscopy results showed that the bulk conductivity can be enhanced by the Li+-doping at the Gd3+-site by almost an order of magnitude. The sample Gd2Zr1.7Li0.3O6.55 had a conductivity lower than that of Gd1.7Li0.3Zr2O6.7 due to the possible trapping of oxygen vacancies by a high-charged acceptor defect LiZrʹʹʹ. The conductivity−pO2 measurements showed that the Li-containing phase was a pure oxide-ion conductor at T

Experimental and theoretical screening of multi-component crystal forms of miconazole (MCL), an antifungal drug, with ten aliphatic dicarboxylic acids was performed. Seven multi-component molecular crystals were isolated and identified by different analytical techniques, including the powder X-ray diffractometry (PXRD), differential scanning calorimetry (DSC), thermogravimetric analysis (TG), and solubility methods. The crystal structures of the MCL hemihydrate, two cocrystals with succinic ([MCL + SucAc] (2 : 1)) and fumaric acids ([MCL + FumAc] (2 : 1)) and one salt with maleic acid ([MCL + MleAc] (1 : 1)) were redetermined. The new cocrystal of MCL with adipic acid ([MCL + AdpAc] (2 : 1)) was investigated by single crystal X-ray diffractometry. It was found that the AdpAc molecule in the cocrystal has an unusual anticlinal conformation. The combination of periodic density functional theory (DFT) computations and quantum topology analysis confirmed the structure-directing role of the acid-imidazole heterosynthon for the considered crystals. The melting temperatures of all the studied multi-component crystals are between the values of the corresponding individual components except [MCL + MleAc] (1 : 1). A thermal analysis has shown that the thermodynamic and thermophysical characteristics of the considered two-component molecular crystals are strongly dependent both on specific interactions (presence of sites of donor-acceptor interactions and hydrogen bond formation) and on nonspecific interactions - molecule polarizability. Based on the sublimation thermodynamics database of molecular crystals, the standard sublimation thermodynamic functions of MCL were evaluated. The thermodynamic functions of multi-component crystal formation based on MCL were calculated and analyzed. Solubility experiments on the MCL multi-component crystals were carried out in isotonic aqueous buffer solutions at pH 1.2 and 6.8 and compared with the solubility of the MCL free base and its nitrate salt. It was found that the salt/cocrystal formation of MCL with dicarboxylic acids considerably increased the MCL solubility in pH 6.8 buffer. The biggest MCL solubility enhancement was observed in the [MCL + TartAc] (1 : 1) salt. The solubility value of MCL in the [MCL + TartAc] (1 : 1) salt is commensurate with the commercial MCL nitrate salt.

Herein, we describe the nonlinear processes for the formation of thin films of the PbS-CdS system using chemical bath deposition with a gradual change in the cadmium nitrate content in the reaction mixture. The morphology of films was studied via scanning electron microscopy and atomic force microscopy. The mechanism for the formation of thin-film compounds can be considered as cluster-particle aggregation (diffusion-limited aggregation). X-ray diffraction confirmed the formation of single-phase layers of substitutional B1-type CdxPb1-xS solid solutions (space group Fm3[combining macron]m) when the concentration of cadmium nitrate in the reaction bath increased up to [Cd(NO3)2] = 0.08 M. The maximum cadmium content in CdxPb1-xS solid solutions was determined to be x = 0.094. At the concentration of [Cd(NO3)2] = 0.10 M, a two-phase film was formed, where the film consisted of crystallites of cubic CdxPb1-xS with x = 0.071 (lower compared to the film obtained at [Cd(NO3)2] = 0.08 M) and fine-crystalline hexagonal B4-type Cd1-δS (space group P63mc). The texture of grains forming films was observed; where a predominant orientation with the (111) plane along substrate in PbS changed to the (200) plane in CdxPb1-xS films, the portion of (200) oriented grains increased with an increase in cadmium nitrate content up to [Cd(NO3)2] = 0.08 M, and at 0.10 M of cadmium nitrate, a radical change in the type of texture to the (111) type occurred. The concentration [Cd(NO3)2] = 0.10 M is called the critical concentration, where under this condition, the deposition process occurs due to the excess Gibbs energy. The higher cadmium content x in films determined by the energy-dispersive X-ray analysis and Auger spectroscopy compared with that estimated from the crystal lattice parameter is associated with the presence of an additional amorphous CdS phase formed as a sublayer distributed in intercrystalline spaces and island formations. Optical studies showed a nonlinear change in the band gap (Eg) of obtained films from 0.53 to 0.76 eV, whereas at the critical cadmium salt concentration (0.10 M), two crystalline phases with Eg equal to 0.73 and 2.47 eV were observed.

Guar gum is a polymer that is widely used as a gelling agent for technological liquids in the petroleum industry. In this paper, we have studied the potential for the environmentally friendly biodegradation of guar gum by enzymes of basidiomycetes for efficient disposal of oil industry wastes. For the first time, we compared the enzymatic activity towards guar gum of seven basidiomycete strains, namely Trametes hirsuta MT-24.24, Lactarius necator, Trametes hirsuta MT-17.24, Schizophyllum commune MT-33.01, Fomes fomentarius MT-4.05, Fomitopsis pinicola MT-5.21, and Trametes versicolor It-1. This comparison showed that the preparation based on Fomitopsis pinicola MT-5.21 fungal mycelium at a concentration of 0.05% provides the most efficient decomposition of a frac fluid containing guar gum. By varying the enzyme concentration in this fluid it is possible to control the decrease in its viscosity over time. The developed enzyme preparation is an efficient and environmentally friendly guar gum biodegradant and can be used to process waste fracturing fluids based on polysaccharides in order to reuse water resources. Key words: biodegradants, basidiomycetes, guar gum, enzymatic hydrolysis, enzyme destructors, fracturing fluids. Funding - The work was financially supported by the National University of Oil and Gas "Gubkin University" (Internal grant no. 120720 "Development of New Biotechnological Methods and Materials for Environmental Protection and Biomedicine").

Improvement of physical and mechanical characteristics of mineral-filled polyethylene (MFPE) upon addition of alumina nanofibers with a high aspect ratio has been experimental studied. It is shown that, at the weight concentration of alumina nanofibers of 0.1 wt %, the ultimate tensile strength increases from 3.82 ± 0.04 to 6.70 ± 0.07 MPa and the Young’s modulus increases from 1.08 ± 0.01 to 1.38 ± 0.01GPa (with respect to MFPE). The MFPE/Al2O3 nanofiber composite can be described within a model of weak adhesive interaction between a filler and a matrix with high friction.

Chemical deposition is used to obtain thin solid films of lead sulfide Pb(S, O) with oxygen contents of 0.2 to 30.7 at %, regulated by a variety of ligands. The oxygen effect on the mechanism of formation and optical properties of Pb(S, O) films is studied experimentally and through quantum-chemical modeling. A heterostructured nature of the synthesized Pb(S, O) compounds is shown for the first time, and a mechanism of their formation in an aqueous solution is proposed.

The role of substrates of different natures on the phase composition, morphology, and mechanical stresses at the “film–substrate” interface during the chemical deposition of CdPbS layers on silicon (111), glass ceramics, fused quartz, an indium–tin–oxide (ITO) coating, slide glass, and porous glass is studied. It is assumed that the revealed features are associated with different conditions of film nucleation and growth. It is found that a single-phase CdxPb1 – xS solid solution film is formed on fused quartz, in contrast to other substrates on which layers containing additionally from 2 to 8 mol % of the X-ray amorphous CdS phase are deposited. It is shown that an increase in mechanical compressive stresses at the “film–substrate” interface from –9.32 to –121.79 kN/m2 in the series porous glass–object glass–glass ceramics–silicon (111)–fused silica is asymbatic to the thermal-expansion coefficients of these substrate materials.

The character of deformation and damage to topocomposites upon instrumental indentation has been investigated. A topocomposite is considered as a layered system consisting of a thin hard coating coherently bound with a substrate made of a compliant solid material. Studies have been performed for a topocomposite consisting of a titanium nitride coating applied by means of magnetron sputtering in vacuum onto an aluminum alloy substrate. By comparing the energy balance of the model and experimental indentation diagrams, the amount of work done in deforming the layered system, in the interfacial separation at the coating-substrate interface, and in the formation of through-the-thickness annular cracks in the coating is assessed. The results of studies can be used for a qualitative assessment of the serviceability of functional surfaces for the machine parts hardened with coatings.

Proportions of 13C/12C and 15N/14N isotopes were identified in different woody compartments of birch (Betula pendula Roth), pine (Pinus sylvestris L.) and aspen (Populus tremula L.) trunks in preforest-steppe and pine-birch forests of the Middle Urals using mass spectrometry. The data were analyzed and interpreted from the perspective of the biochemical processes of carbon and nitrogen metabolism in leaves, cambial tissue, trunk wood, branches, roots, and soil. A lighter isotopic composition of carbon is characteristic of the leaves and trunk cambium. The trunk wood is characterized by a basal trend for 13C enrichment. The 13C/12C ratio corresponds to the nitrogen content in the trunk wood tissues, indicating metabolic control of carbon fractionation in woody plants. The isotope composition of nitrogen in the trunk cambium was significantly depleted in 15N (δ15N varies from –1.5 to –3.5‰) and δ13C (δ13C varies from –28.3 to –25.8‰). Meanwhile the sapwood (δ15N varies from –2.6 to 1‰ and δ13C varies from –27.5 to –27.1‰) and heartwood (δ15N varies from –2.5 to –3.5‰ and δ13C varies from –26 to –24.5‰) were more enriched in 15N and 13C. The significant difference between the values of 13C and 15N isotope discrimination consequently in the different woody compartments of trunk should be taken into account when interpreting data of wood organic matter in the context of paleoclimate.

A DNA sequence from Kosakonia sacchari that, according to automated computer analysis, is believed to correspond to the gene for histidine-acid phytase has been selected from the GenBank database. The sequence was optimized for codon composition, synthesized, cloned, and expressed in Pichia pastoris. The main characteristics of the purified recombinant enzyme were determined. It was established that a pH of 4.5 and a temperature of 50°C are optimal for phytase functioning. The specific activity, Michaelis constant (Km), and maximum reaction rate (Vmax) with phytate as a substrate were 1470 U/mg, 193 μM and 2167 μmol/(min mg), respectively. It was shown that the enzyme was characterized by a wide range of working pH levels. Therefore, due to its properties, this new recombinant phytase can be considered a high-potential enzyme for agrobiotechnology.

Polycrystalline films of PbS:Fe are obtained via hydrochemical deposition from an ammonia-citrate bath containing 10−5 to 7 × 10−3 M of FeCl2 doping additive. The films’ morphology is studied along with their structural and optical properties. An increase in the lattice parameter of PbS doped up to 5 × 10‒3 M testifies to the interstitial position of Fe2+ ions, while a subsequent reduction in the lattice parameter is due to some of the lead ions in the PbS crystal lattice being replaced with iron ions of a smaller radius. Doping with iron ions produces impurity absorption bands in the optical absorption spectra of PbS:Fe films. Rearrangement of the zone structure of lead sulfide near the edge of the band gap is observed in a film obtained from a solution containing 5 × 10−3 M FeCl2. The change in the zone structure is due to the lead ions in the PbS lattice being replaced with iron ions.

Evolution of the morphology, composition, structural characteristics (lattice constant, microstrains, texturing), and optical and photoelectric properties of PbS films produced by chemical bath deposition in the presence of ammonium iodide and strontium or barium chlorides at a concentration up to 5 mM is studied. According to the data of energy dispersive X-ray analysis, the content of strontium in the PbS films is 0.4–0.7 at %, whereas the content of barium is beyond the determination error. The size of the particles forming the films varies from ~200 to ~400 nm, and the size distribution of the particles is monomodal. The introduction of NH4I and SrCl2 or BaCl2 into the reactor retains the B1 cubic structure of lead sulfide, but gives rise to an unsteady change in the lattice parameter, which is due to the creation of vacancy-type or interstitial ion defects. The introduction of salts of strontium or barium does not influence the band gap, but changes the intensities of the impurity absorption bands deep in the band gap or near the bottom of the conduction band. The dependences of the volt–watt sensitivity of the films on the content of salts of strontium and barium are of an extreme character and show maxima at 0.05 and 0.1 mM, respectively.

We studied the nature of deformation and damage of topocomposites with instrumental indentation. The topocomposite is considered as a layered system consisting of a solid thin coating coherently bonded to a substrate of a ductile solid material. The object of the study is a topocomposite that consists a coating of titanium nitride deposited by magnetron sputtering in vacuum on a substrate of aluminum alloy. Comparing the balance of energy spent at all stages of indentation using model and experimental diagrams of indentation, the contribution of work dissipated on the deformation to the layered system, on the interfacial delamination at the coating-substrate interface and on the formation of through circular cracks in the coating is estimated. The research results can be used for a qualitative estimation of the efficiency of functional surfaces of machine parts hardened with coatings and for calculating the characteristics of deformation and damage.

Comparative experimental data, using dynamic light scattering methods, scanning electron and atomic force microscopy, on the composition, crystal structure, semiconductor and photoelectric properties of PbSe films deposited at the presence of sodium sulfite Na2SO3 and “sodium sulfite–ascorbic acid” complex antioxidant additive are presented. Significant changes in morphology, elemental and phase composition, the period of the crystal lattice of PbSe films been synthesized in the presence of Na2SO3 and Na2SO3 + C6H8O6 anti-oxidants before and after their thermoactivation at 653 K are found. It is shown that the introduction of a complex additive in comparison with Na2SO3 increases the homogeneity of the particles forming the layer, decreases the microstresses in it, reduces the value of thermal band gap from 0.349 to 0.308 eV, and increases the volt-watt sensitivity of the films by 28–30%.

Lead selenide thin films produced by hydrochemical deposition with the use of ascorbic acid as an antioxidant of selenourea have been studied by X-ray diffraction analysis, scanning electron microscopy with elemental analysis, and X-ray photoelectron spectroscopy. The effect of the annealing temperature on the elemental composition of the films, their phase composition, crystal lattice parameters, surface morphology, and photoelectric properties has been determined. It is established that, after annealing at 633–683 K, the films contain the PbSeO3, PbSeO4, and PbI2 impurity phases. The optical band gap Eg of the layers in the cases of indirect and direct transitions has been determined. It has been shown that, in terms of their threshold photoelectric characteristics, the deposited films are comparable to widely known commercial samples and can be used to produce highly sensitive infrared detectors.

Over the past decades, a large number of studies have been published to confirm the role of intestinal microbiota in the pathogenesis of functional intestinal disorders. The authors presented a review of the main mechanisms through which various microorganisms that colonize the digestive tract, have a beneficial effect on the human body. The results of experimental studies, that confirmed the ability of various bacteria to provoke the development of bacterial overgrowth syndrome, irritable bowel syndrome, functional constipation, have been presented. The data providing evidence of the intestinal microbiota role in the progression of celiac disease have been considered. The efficacy of various methods of restoration of intestinal eubiosis by non‑absorbable antibiotics (rifaximin), probiotics, fecal microbiota transplantation is analyzed. The data have been presented that confirm the expediency of rifaximin use in irritable bowel syndrome. In addition to the traditional bactericidal and bacteriostatic properties of many antibiotics, there is an evidence of additional eubiotic activity in rifaximin. The results of meta‑analyses studying the efficacy of various probiotics in the treatment of functional constipation are considered. The ambiguity of the evidence base with respect to the fecal microbiota transplantation for treatment of refractory irritable bowel syndrome is underlined. The expediency of inclusion of eubiotics in treatment of functional intestinal diseases is proved. Further research is needed to determine the prospects of treatment of intestinal dysbiosis in functional intestinal disorders with probiotics., На протяжении последних десятилетий опубликовано большое количество исследований, подтвердивших роль кишечной микробиоты в патогенезе функциональных заболеваний кишечника. Рассмотрены основные механизмы, посредством которых микроорганизмы, колонизирующие пищеварительный тракт, оказывают благотворное влияние на организм человека. Приведены данные экспериментальных исследований, подтвердившие способность разных бактерий провоцировать развитие синдрома избыточного бактериального роста, синдрома раздраженного кишечника и функционального запора. Рассмотрены доказательные данные, подтверждающие роль микробиоты кишечника в прогрессировании целиакии. Проанализирована эффективность разных способов восстановления эубиоза кишечника: посредством применения невсасывающихся антибиотиков (рифаксимина), пробиотиков, трансплантации фекальной микробиоты. Представлены данные о целесообразности применения рифаксимина при синдроме раздраженного кишечника. Приведены доказательные данные, подтверждающие наличие у рифаксимина, помимо бактерицидных и бактериостатических свойств, присущих многим антибиотикам, эубиотической активности. Рассмотрены результаты метаанализов, изучавших эффективность разных пробиотиков в лечении функционального запора. Подчеркнута неоднозначность доказательной базы в отношении проведения трансплантации фекальной микробиоты для нивелирования рефрактерного синдрома раздраженного кишечника. Доказана целесообразность включения эубиотиков в схемы лечения функциональных заболеваний кишечника. Необходимо провести исследования для определения перспектив лечения дисбиоза кишечника при функциональных заболеваниях пищеварительного тракта при помощи пробиотиков., Протягом останніх десятиліть опубліковано велику кількість досліджень, які підтвердили роль кишкової мікробіоти в патогенезі функціональних захворювань кишечника. Розглянуто основні механізми, за допомогою яких мікроорганізми, котрі колонізують травний тракт, сприятливо впливають на організм людини. Наведено результати експериментальних досліджень, які підтвердили здатність різних бактерій провокувати розвиток синдрому надлишкового бактеріального росту, синдрому подразненого кишечника і функціонального запору. Розглянуто доказові дані, котрі підтверджують роль кишкової мікробіоти у прогресуванні целіакії. Проаналізовано ефективність різних способів відновлення еубіозу кишечника: за допомогою застосування антибіотиків, які не адсорбуються (рифаксиміну), пробіотиків і трансплантації фекальної мікробіоти. Представлено дані щодо доцільності застосування рифаксиміну при синдромі подразненого кишечника. Наведено доказові дані, які підтверджують наявність у рифаксиміну, крім бактерицидних і бактеріостатичних властивостей, притаманних багатьом антибіотикам, еубіотичної активності. Розглянуто результати метааналізів, в яких вивчали ефективність різних пробіотиків у лікуванні функціонального запору. Наголошено на неоднозначності доказової бази щодо доцільності проведення трансплантації фекальної мікробіоти з метою нівелювання рефрактерного синдрому подразненого кишечника. Доведено доцільність включення еубіотиків у схеми лікування функціональних захворювань кишечника. Необхідно провести дослідження для визначення перспектив лікування дисбіозу кишечника при функціональних захворюваннях травного тракту за допомогою пробіотиків.

A smooth synthesis of 4H-[1,2,3]triazolo[4,5-c][1,2,5]oxadiazole 5-oxide 1 and its energetic salts (ammonium, hydroxylammonium, guanidinium, triaminoguanidinium) is reported. The compounds synthesi...

A potentially new calcium-rich eudialyte-group mineral from the Khibiny massif has been investigated by X-ray diffraction (XRD) analysis. The trigonal unit-cell parameters are found to be as follows: a = 14.221(1) A, c = 30.04(1) A, and V = 5261.3 A3; sp. gr. R3m. The crystal structure is refined to the final reliability factor R = 2.8% in the anisotropic approximation of atomic displacements, using 1714 reflections with F > 3σ(F). The idealized formula of the mineral (Z = 3) is (Na12Ca3)Ca6Fe $$_{3}^{{2 + }}$$ Zr3NbSi25O75(H2O,OH,F,Cl)3. The dominance of divalent iron form is confirmed by Mossbauer spectroscopy data. The closest analog of the mineral under study is feklichevite from the Kovdor alkaline massif; the main difference is the dominance of divalent iron over trivalent iron in the former.

Pharmaceutical dosage forms with diosmin in Russian Federation are allowed for medical using. Simple and informative methods of diosmin quantitation for drug quality control are needed. Background. The metrological parameters determination of diosmin quantitation in pharmaceutical dosage forms by UV-spectrophotometry. Methods. The study subject was Venarus®, Detralex® (tablets, suspension), Phlebopha®. Diosmin was quantified by UV-spectrophotometry. The reference-specific absorbance values of diosmin at wavelengths of 268 nm and 370 nm by the parameters of calibration was determined. Statistical data processing was carried out by methods of variation statistics, correlation, one-way analysis of variance using computer programs ChemMetr 1.0, ChemMetr Evaluation 1.0, Statistica 6.0 (Statsoft Inc., USA). Result. The range of diosmin quantitation by UVspectrophotometry was for wavelengths: 268 nm – 0,0001-0,001%, 370 nm – 0,0002-0,002%. The referencespecific absorbance values for diosmin at wavelengths of 268 nm and 370 nm in a sodium hydroxide solution 0,02M were 463,0±24,6 and 259,0±9,9 respectively. The means errors of diosmin concentrations in pharmaceutical dosage forms were for wavelength 268 nm – 8-12% and for 370 nm – 6-8%. On example Detralex® tablets analysis a prognostic calculation of the sample preparation error (extraction) for diosmin was performed. The sample preparation error was 8%. Conclusion. The values components of error for referencespecific absorbance value and sample preparation error for diosmin quantitation was determined (on example analysis Detralex® tablets). Calculation algorithms can be used to theoretically error estimate of sample preparation for other multicomponent samples in drug quality control.

Introduction. Pharmaceutical dosage forms with diosmin are allowed for medical use in Russian Federation. Simple and informative methods of diosmin quantitation for drug quality control are needed. Aim: determination of metrological parameters of diosmin quantitation in pharmaceutical dosage forms by UV-spectrophotometry. Matherials and methods. The study subjects Venarus, Detralex (tablets, suspension), Phlebopha. Diosmin were quantified by UV-spectrophotometry. The reference-specific absorbance values of diosmin at wavelengths of 268 and 370 nm by the parameters of calibration were determined. Statistical data processing was carried out by the methods of variation statistics, correlation, one-way analysis of variance using computer programs ChemMetr 1.0, ChemMetr Evaluation 1.0, Statistica 6.0 (Statsoft Inc., USA). Results. The range of diosmin quantitation by UV-spectrophotometry was revealed for the wavelength of 268 nm 0,0001-0,001%, 370 nm 0,0002-0,002%. The reference-specific absorbance values for diosmin at the wavelength of 268 and 370 nm in a sodium hydroxide solution 0,02M were 463,0 24,6 and 259,0 9,9 respectively. The mean errors of diosmin concentrations in pharmaceutical dosage forms were revealed for the wavelength of 268 nm 8-12% and for 370 nm 6-8%. Prognostic calculation of the sample preparation error (extraction) for diosmin was performed using the example of Detralex tablets. The sample preparation error was 8%. Conclusion. The values components of error for reference-specific absorbance value and sample preparation error for diosmin quantitation were determined (as exemplified by the study of Detralex tablets). Calculation algorithms can be used for error estimation of sample preparation for other multicomponent samples in drug quality control.

This paper considers the mechanism of formation and structure of boundary lubricating films on the metal surface in the presence of different types of additives, namely fatty acids and cholesteric-type mesogens, whose molecules have a phenanthrene skeleton. The results of laboratory studies of the tribological properties of industrial oil I-30A supplemented with the indicated types of additives in various concentrations are presented. The studies were carried out on a four-ball friction machine according to the standard method, and the main indicators of the lubricating ability of oil samples with additives, such as the diameter of the wear spot, critical load, scoring index, and welding load, were determined. According to the obtained results, it was found that the greatest positive effect on the lubricating ability of industrial oils is exerted by a liquid crystal additive, when compared to fatty acid, and the maximum anti-wear effect is observed at concentrations lying within the studied range. These data indicate the presence of a region of rational concentration of the liquid crystal additive in industrial oil.

The paper proposes the manufacturing methods for modifying coatings for gas-diffusion membranes made of palladium-silver alloy comprising 23% Ag. Highly developed surface structures are synthesized to intensify chemisorption and dissociation and to accelerate the overall process of hydrogen transmission through the membrane. At a 0.6 MPa hydrogen overpressure and 100°C temperature, the density of the hydrogen flow through Pd/Ag23 wt.% membrane with the developed surface is 7 times higher than through the similar membrane without the modifying layer. The analysis of the proposed methods shows that the hydrogen density passing through the membranes with the modifying coating synthesized by a method with the included recrystallization stage, is 1.3 times higher than through the similar membranes synthesized in accordance with the standard procedures. The experiments show that the hydrogen transmission rate can be increased in the surface limited regime by creating a highly developed structure of the membrane surface.

The use of calcium carbide (in the presence of H2O) as a source of acetylene in the reaction with methyl 2-amino-4,6-O-benzylidene-2-deoxy-β-d-glucopyranoside under superbasic conditions (KF, KOH, DMSO, 130 °C, 3 h) led to the corresponding vinyl ether in 78% yield. The vinylation does not affect other reaction centers. Replacement of water with deuterium oxide in the reaction mixture gave a stable deuterated analog of this vinyl ether in 72% yield. The one-step isotopic enrichment was practically quantitative (isotopic purity >96%). Introduced deuterium atoms can be used as a convenient label in further transformations.

Verapamil is a drug that can be toxic in pharmacological therapy and in case of misuse. Simple and informative methods of Verapamil quantification for forensic chemistry and hospital toxicology are needed. Aim. The objective of the study was to compare analytical potential of different methods for Verapamil quantification used in forensic chemistry and hospital toxicology. Materials and methods. The subject study was whole blood samples containing Verapamil. Verapamil in the blood samples was identified by gas chromatography-mass-spectrometry. Verapamil was quantified by thin-layer chromatography with videodensitometry and UV-spectrophotometry. Results. To quantify Verapamil content, the plates were scanned, the chromatogram images were processed and calibration models were given by means of computer program. The calibration model is described by polynomial (square) regression. In UV-spectrophotometry absorbance of samples at the wavelength of 277 nm was measured; blank blood extracts as a zero reference were used. The limits of quantifation for thin-layer chromatography with videodensitometry and UV-spectrophotometry were 300,0 and 6000,0 ng/ml respectively. The accuracy and precision for thin-layer chromatography with videodensitometry failed to exceed 20.2 и 24.3% respectively; for UV-spectrophotometry they were 27.5 и 7.4%. Conclusion. The ranges of quantifation make it possible to use thin-layer chromatography with videodensitometry for forensic chemistry and hospital toxicology. UV-spectrophotometry can be used to quantify Verapamil content in blood samples at the lethal concentration range.

—In an experimental model of Parkinson’s disease, the dopamine content in the striatum, the density of TH+ neurons in the substantia nigra, and the motor activity of mice were studied after the administration of afobazole, which interacts with Sigma-1 and MT1 receptors and regulatory sites of MAO-A and quinone reductase 2 (NQO2, MT3 receptor), and its main metabolite M-11, which selectively interacts only with the regulatory site of NQO2. The drugs were administered intraperitoneally for 14 days with the start of the course 30 minutes after unilateral intrastriatal administration of 5 μg of 6‑hydroxydopamine (6‑OHDA). Afobazole and M‑11 showed neuroprotective properties. In all experiments, the effective dose of afobazole (2.5 mg/kg) was significantly lower than M-11 (7.5 mg/kg). The experimental model used shows the contribution of NQO2 and other drug targets to the antiparkinsonian effect of afobazole.

Differences between factory and wild juvenile salmons (fingerlings at the 0+ age and 1+ parrs) in the content of physiologically significant fatty acids and their ratios are shown. Factory juveniles (age 0+ and 1+) have a very low content of physiologically significant 18:3n-3 and 20:4n-6 fatty acids when compared with wild individuals, whereas relatively high amounts of 22:6n-3 (age 0+) and 18:2n-6 fatty acids (age 1+) were noted. Simultaneously, the factory juveniles (age 0+ and 1+) differ from wild juveniles in a lower ratio of 18:3n-3/18:2n-6 essential fatty acids (by 7.9 and 6.4 times, respectively). The ratio of total polyunsaturated n-3/n-6 fatty acids is reliably equal in wild and factory fingerlings (age 0+), whereas it is 2 times lower in parrs than in factory fish. A relatively high content of oleic 18:1n-9 fatty acid and minor 20:1n-9, 22:1n-11 fatty acids are found in the factory juveniles, but the level of saturated fatty acids decreases due to 16:0 and 18:0. The high metabolic rate of fatty-acid metabolism in wild juveniles is evidenced by a higher ratio of 16:0/18:1n-9 compared to that in the factory fish (1.50 and 1.47 vs 0.84 and 0.46 for fingerlings (age 0+) and parrs (age 1+), respectively). The lower metabolic rate of fatty acid metabolism in factory juveniles, especially for parrs (age 1+), is accompanied by a high accumulation of their body mass (in fourfold) when compared with wild individuals of the same age.

The photocatalytic degradation of organic molecules is one of the effective ways for water purification. At this point, photocatalytic microreactor systems seem to be promising to enhance the versatility of the photoassisted degradation approach. Herein, we propose photoresponsive microcapsules prepared via layer-by-layer assembly of polyelectrolytes on the novel CaCO3/TiO2 composite template cores. The preparation of CaCO3/TiO2 composite particles is challenging because of the poor compatibility of TiO2 and CaCO3 in an aqueous medium. To prepare stable CaCO3/TiO2 composites, TiO2 nanoparticles were loaded into mesoporous CaCO3 microparticles with a freezing-induced loading technique. The inclusion of TiO2 nanoparticles into CaCO3 templates was evaluated with scanning electron microscopy and elemental analysis with respect to their type, concentration, and number of loading iterations. Upon polyelectrolyte shell assembly, the CaCO3 matrix was dissolved, resulting in microreactor capsules loaded with TiO2 nanoparticles. The photoresponsive properties of the resulted capsules were tested by photoinduced degradation of the low-molecule dye rhodamine B in aqueous solution and fluorescently labeled polymer molecules absorbed on the capsule surface under UV light. The exposure of the capsules to UV light resulted in a pronounced degradation of rhodamine B in capsule microvolume and fluorescent molecules on the capsule surface. Finally, the versatility of preparation of multifunctional photocatalytic and magnetically responsive capsules was demonstrated by iterative freezing-induced loading of TiO2 and magnetite Fe3O4 nanoparticles into CaCO3 templates.

Lead sulfide films doped with cadmium and iodine ions were obtained by chemical bath deposition from the reaction mixture with thiourea that have thickness of up to 300 nm. An increase in cadmium iodide in the reactor from 5∙10-5 to 5∙10-3 mol/l is accompanied by a decrease in the period of the B1 cubic crystal lattice (space group ) from 0.59368 to 0.59355 nm, due to the replacement of Pb2+ ions in the PbS crystal lattice by a smaller size of ion Cd2+. The cadmium content in the synthesized layers varied from 0.4 to 2.8 at.% with a constant iodine concentration of 1.7–1.9 at.%. An electron microscopic study of the structure showed a decrease in the average crystallite size from 260 nm to 80 nm.

Crystal structure features of NaFeO2 and NaAlO2 were studied using neutron diffraction and X-ray powder diffraction. The conductivity of these compounds was also investigated. The migration paths in the structure of sodium ferrite and aluminate were modeled by topological (tiling) and DFT methods. The sizes of through sodium-cations migration channels in low-temperature β-modifications of the compounds in question were determined using the ToposPro software package. It is shown that an increase in the size of these migration channels correlates with an increase in ionic conductivity. The conductivity in high-temperature γ-phases of NaFeO2 and NaAlO2 is determined by two competing processes: an increase in activation energy caused by a decrease in the cross-sections of the channels and a transition from one-dimensional conductivity to three-dimensional one.