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A method for quantitative determination of myricitrin in common myrtle (Myrtus communis L.) leaves using high-performance liquid chromatograph (HPLC) was developed. The content of the dominant flavonoid myricitrin (myricetin 3-O-α-L-rhamnopyranoside) in common myrtle leaves varied from 0.98 ± 0.02% to 1.51 ± 0.07%. The error of a single determination and the average error of the myricitrin content determination in common myrtle leaves were ±15.81% and ±4.77%, respectively, with confidence probability 95%. [ABSTRACT FROM AUTHOR]

The structure of aqueous dispersions of phospholipid transport nanosystem (PhTNS) based on soybean phospholipids developed at the Institute of Biomedical Chemistry (Moscow, Russia) was studied by the method of small-angle X-ray scattering. The PhTNS concentrations in water were 20, 25, 31.25, and 37.5%. The structural parameters of vesicles (inner radius, thicknesses of the regions of hydrophobic tails and polar heads) were determined in the "core/multi-shell model" approximation with variations in the scattering length densities of vesicle different parts, as well as the solution that was inside and outside the vesicle. A difference in the photon scattering length densities was detected between the solution volume and the inner region of the vesicle due to the uneven maltose dissolution, which was part of PhTNS. With an almost constant thickness of the lipid bilayer, a decrease in the vesicle radius from ~150 to ~130 Å was observed with increasing concentration of the system which was due to increasing osmotic pressure. The hydrophobic volume of vesicles was determined to be 7.45 × 106 Å3 at the lowest concentrations of 20% and 5.85 × 106 Å3 at the highest concentration of 37.5%. [ABSTRACT FROM AUTHOR]

Vascular prosthesis samples were synthesized from polyurethane based on polypropylene glycol terminated with 2,4-toluylenediisocyanate. The outer and inner surfaces of the implants were treated with high-energy nitrogen ions of 20 and 10 keV, respectively. As a result of ion-plasma treatment, an active hydrophilic carbon nanolayer was formed on the implant surfaces. The tropoelastin protein was applied to the inner and outer surfaces of the samples treated by the ion-plasma method. Plasma-treated and untreated prosthetic specimens were implanted into the carotid artery of rabbits. After 1 week of exposure, a morphological assessment of the tissues surrounding the walls of intravascular prostheses was carried out. It was shown that blood clots had formed inside all the prostheses. However, the morphological picture of the tissues around the walls of plasma-treated implants was characterized by accelerated channeling of clots and endothelial proliferation from the intima of the vessel compared to untreated implants. [ABSTRACT FROM AUTHOR]

Considering the side effects of existing drugs used for pain relief, the search for new analgesics with high efficacy and safety remains relevant. Aseries of imidazopyrrolo[3,4-b]quinoline-5,11-diones and pyrimidopyrrolo[3,4-b]quinoline-6,12-diones II were synthesized, whose analgesic activity at a dose of 0.05 mmol/kg was studied in the hotplate test in rats after i.p. administration. One compound was found with analgesic activity comparable to that of reference compound diclofenac sodium. Compounds II were less toxic than diclofenac sodium. [ABSTRACT FROM AUTHOR]

This article discusses agricultural development trends in Russia, the results of import substitution in the agricultural sector of the economy, and means of ensuring the country's food security. The consumption differentiation within the main types of agricultural products and food is shown depending on the income level of the population. The problem of import substitution associated with the provision of the agroindustrial complex with domestic material and technical resources is analyzed. It is noted that the duration of the import substitution process for various types of agricultural products will largely depend on the effectiveness of the organizational and economic mechanism in the agroindustrial complex (AIC). Growth opportunities in the agricultural sector due to taking over the market share occupied by imports are limited. With the development of import substitution, conditions will be created for increasing the export of agricultural products and foodstuffs and for the transition from import dependence to the development of export potential. [ABSTRACT FROM AUTHOR]

Medical grade SKU-PFL polyurethane was treated with 20-keV nitrogen ions and implanted to rats. After one month, tissues with implanted polyurethane were sampled for histological analysis. Statistical analysis showed that the thickness of the tissue capsule around the foreign body is significantly lower for samples treated with polyurethane than for untreated samples. [ABSTRACT FROM AUTHOR]

The design of robust and inexpensive molecular photocatalysts for the conversion of abundant stable molecules like H2O and CO2 into an energetic carrier is one of the major fundamental questions for scientists nowadays. The outstanding challenge is to couple single photoinduced charge separation events with the sequential accumulation of redox equivalents at the catalytic unit for performing multielectronic catalytic reactions. Herein, double excitation by nanosecond pump–pump–probe experiments was used to interrogate the photoinduced charge transfer and charge accumulation on a molecular dyad composed of a porphyrin chromophore and a ruthenium-based catalyst in the presence of a reversible electron acceptor. An accumulative charge transfer state is unattainable because of rapid reverse electron transfer to the photosensitizer upon the second excitation and the low driving force of the forward photodriven electron transfer reaction. Such a method allows the fundamental understanding of the relaxation mechanism after two sequential photon absorptions, deciphering the undesired electron transfer reactions that limit the charge accumulation efficiency. This study is a step toward the improvement of synthetic strategies of molecular photocatalysts for light-induced charge accumulation and more generally, for solar energy conversion. [ABSTRACT FROM AUTHOR]

Sodium cholate is a bile acid salt, which is applied as a biological detergent. The mixed systems of phospholipid/sodium cholate are used to study the self-assembly of micelles and formation of micellar systems. The micelles consisting of a phospholipid/sodium cholate mixture are used for drug delivery through the skin. An important part of the investigations in this field is examination of the structure and properties of micelles consisting of sodium cholate molecules. The structure of sodium cholate micelles have been investigated by small-angle neutron scattering. The average radius of sodium cholate micelles in the sodium cholate concentration range of 25‒100 mM is found to be 10.14 ± 0.01 Å. [ABSTRACT FROM AUTHOR]

Antioxidant properties of arylhydrazones in sunflower oil oxidation and regular trends in variation of the antioxidant activity of arylhydrazones in the process in comparison with ethybenzene oxidation were examined. [ABSTRACT FROM AUTHOR]

The features of transparency field generation in the upper sea layer of the northwestern Black Sea in the winter-spring period are analyzed on the basis of long-term data of specific marine observations from 1978-1995. The statistical assessments of the seasonal variations of the beam attenuation coefficient associated with fluctuations of river discharge and open sea water characteristics are calculated for the region under study. It is shown that the amount of suspended matter, which is most responsible for seawater transparency, depends both on rivers' discharge volumes, the area of their interaction with seawater over the northwestern Black Sea shelf, and regional hydrometeorological conditions, which in turn depend on the hydrometeorological conditions in the catchment areas of the European rivers of the Black Sea basin. [ABSTRACT FROM AUTHOR]

The article presents a research study which focuses on the cyclonic variances in winter and spring seasons within the regions of the Black and Mediterranean Seas. It mentions the detection of cyclones on these regions through NCEP/NCAR data reanalysis and North Atlantic Oscillation (NAO). Furthermore, the interannual cyclonic activities are also cited.

On the basis of analysis of product composition in the hydrolytic polycondensation (HPC) of chlorotriorganosilanes, the parameters of the kinetic and the diffusion field, the zone of the reaction, and the region of the conodes of the phase diagrams are determined. It is suggested that the conodes correspond to a phase quasiequilibrium, which defines the composition of the reaction products. The results of this investigation confirm the previously discovered features of HPC of dichloromethylphenylsilanes: the formation of the siloxane bond during the hydrolysis of chloroorganosilanes by water mainly occurs in the organic phase of the system and proceeds as the heterofunctional polycondensation of the reaction products with the starting chloroorganosilanes. The role of the phase quasiequilibrium consists of the creation of a field of reagent concentration, based on which one can control the composition of the reaction products. [ABSTRACT FROM AUTHOR]

The condensation of the thiuronium salt from 1-vinyl-6-methoxy-1-tetralol with 2-(carbethoxymethyl)-dihydroresorcinol smoothly gives the 18-carbethoxysecosteroid (III), from which, depending on the reaction conditions, the 18-carbethoxy derivatives of D-homoequilenin or D-homoestrone can be obtained by acid cyclization. [ABSTRACT FROM AUTHOR]