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A combinatorial topological analysis and modeling of the self-assembly of crystal structures of LiCaSn-hP9 (space group P3m1, V = 230.36 A3), Li2CaSn- cF16 (space group Fm-3m, V = 333.56 A3), and Li20Ca28Sn44-oS92 (space group Cmcm, V = 2517.09 A3) are performed using computer methods (ToposPro software package). The cyclic precursor clusters K3-0@LiCaSn involved in the self-assembly of the crystal structure of LiCaSn-hP9, as well as tetrahedral ones K4 for the crystal structure of Li2CaSn-cF16 and cyclic K3, tetrahedral K4, and pentagonal pyramids K6 for the crystal structure of Li20Ca28Sn44-oS92, are established. The self-assembly of the crystal structure of Li20Ca28Sn44-oS92 involves $${\text{S}}_{3}^{1}({\text{A}})$$ primary chains from the bound clusters K6 and K3, and $${\text{S}}_{3}^{1}({\text{B}})$$ primary chains from the bound clusters K4 and K3. In the 2D layer, an $${\text{S}}_{3}^{1}({\text{A}})$$ chain with m symmetry is bound to the $${\text{S}}_{3}^{1}({\text{B}})$$ chains on both sides. The framework $${\text{S}}_{3}^{3}$$ structure is formed by binding 2D layers in the direction [100], whereas the distance between the equivalent 2D layers determines the value of vector a = 4.666 A. The $${\text{S}}_{3}^{1}$$ primary chain of the intermetallic compound Li2CaSn-cF16 is formed as a result of the binding of tetrahedral metal clusters Li2CaSn with the binding index P = 8. The formation of the $${\text{S}}_{3}^{2}$$ layer occurs by binding parallel chains with the index P = 10. The distance between the axes of the primary chains from neighboring layers in the direction of axes X and Y corresponds to the value of the parameters of the cubic cell a = b = 6.935 A. The $${\text{S}}_{3}^{1}$$ primary chain of the intermetallic compound LiCaSn-hP9 is formed as a result of the binding of the cyclic LiCaSn metal clusters with the binding index P = 4 and 5. The $${\text{S}}_{3}^{2}$$ layer is formed by binding parallel chains with the binding index P = 10. The distance between the axes of the primary chains corresponds to the value of the parameter of the hexagonal cell a = 4.94 A.

Composites based on polypropylene and single-wall carbon oxygen-containing nanotubes with a specific surface area of 360 and 500 m2/g are synthesized in the medium of liquid propylene using the catalytic system rac-Me2Si(2-Me-4-PhInd)2ZrCl2/МАО. Optimum polymerization conditions ensuring a fairly high rate of the process are determined, and the composites with the filler content in the range from 0.3 to 13.0 wt % are obtained. It is shown that the presence of functional groups enhances the filler agglomeration tendency during composite formation. Effects of the type of carbon nanofiller on the thermal stability, thermo-oxidative resistance, and thermal and electrophysical characteristics of the composites are studied. It is found that the filler inhibits the processes of oxidation and destruction of polypropylene crystallites.

The cytotoxicity of doxorubicin (Dox) and its peptide modifications Z-Gly-Pro-Dox and Boc-Gly-Pro-Dox were studied. Tetrahymena pyriformis was used as a test system, which made it possible, due to the short life cycle and high reproduction rate of ciliates, to trace their response to the effects of toxicants over several generations. It was found that peptide modification of the Dox molecule markedly reduces its cytotoxic and cytostatic effect. The Z-Gly-Pro-Dox modification has less cytotoxic and cytostatic effect compared to Boc-Gly-Pro-Dox. When determining the ability of drugs (at a concentration of 100 μM) to prevent bacterial contamination of samples, it was shown that the smallest degree of overgrowth was recorded in the presence of Dox (OD600nm 81.1). Boc-Gly-Pro-Dox also had a bacteriostatic effect, though less pronounced (OD600nm 93.8). The degree of overgrowth in the presence of Z-Gly-Pro-Dox was close to that of distilled water. The results obtained on ciliates did not contradict the data obtained in similar studies on mice.

There is information in the literature about the salts of polyhexamethylene guanidine (PGMG), which are effective biocidal and sterilizing drugs and disinfectants due to the wide range of their antimicrobial activity against gram-positive and gram-negative bacteria (including Mycobacterium tuberculosis), viruses, and fungi. The aim of this work is to study the bactericidal and fungicidal activity of the synthesized polyetherguanidinium chloride against a number of bacteria and microscopic fungi. Methods. Cultivation of microorganisms. Bacteria were grown on meat-peptone agar for 48 hours at a temperature of 28±2°C. Test cultures of micromycetes were cultured on beer wort agar (6°B), incubated for 14 days in a thermostat at a temperature of 28±2°C. Antimicrobial activity of newly synthesized polyetherguanidinium chloride was determined by standard disco-diffusion method, and fungicidal activity was determined by agar diffusion method. Results. The synthesis of polyetherguanidinium chloride was carried out in two stages. The first stage was the synthesis of a guanidinium-containing oligoether with terminal guanidine moieties by the reaction between an aromatic oligoepoxide and guanidine. The second stage was the synthesis of polyetherguanidinium chloride by the reaction between a guanidinium-containing oligoether with terminal guanidine moieties and oligooxyethylenediamine. The bactericidal and fungicidal activity of polyetherguanidinium chloride against various heterotrophic bacteria and microscopic fungi has been shown. It was found that polyetherguanidinium chloride at concentrations of 1–3% inhibited the growth of gram-negative (Escherichia coli 475, Klebsiella pneumonia 479) and gram-positive (Staphylococcus aureus 451) bacteria. The proposed 1% solution of polyetherguanidinium chloride shows a 1.5 times higher antimicrobial activity than the polymeric disinfectant polyhexamethyleneguanidinium chloride for E. coli 475 and K. pneumoniae 479 bacteria and lower antimicrobial activity for S. aureus 451 bacteria. According to the obtained data, it was noted that polyetherguanidinium chloride at a concentration of 1% had a high fungicidal activity against almost all investigated isolates: Aspergillus versicolor F-41250, Acremoneum humicola F-41252, Acremoneum roseum F-41251, Cladosporium sphaerospermum F-41255, Paecilomyces lilacinus F-41256 and Scopulariopsis candida F-41257. Conclusions. Received polyetherguanidinium chloride at a concentration of 1% showed bactericidal activity against S. aureus 451, E. coli 475, K. pneumoniae 479 and fungicidal effect to all fungi studied by us, and so can be used as a disinfectant for building materials.

Diamond–SiC composite materials were obtained by impregnation with gaseous and liquid Si. The mechanisms of the impregnation and consolidation of the diamond–silicon carbide composites were studied. The effect of the Turing reaction–diffusion mechanism on the sintering of the diamond–SiC materials, the formation of the microstructure, and the mechanical properties was shown for the first time.

Many human diseases including cancer, degenerative and autoimmune disorders, diabetes and others are multifactorial. Pharmaceutical agents acting on a single target do not provide their efficient curation. Multitargeted drugs exhibiting pleiotropic pharmacological effects have certain advantages due to the normalization of the complex pathological processes of different etiology. Extracts of medicinal plants (EMP) containing multiple phytocomponents are widely used in traditional medicines for multifactorial disorders' treatment. Experimental studies of pharmacological potential for multicomponent compositions are quite expensive and time-consuming. In silico evaluation of EMP the pharmacological potential may provide the basis for selecting the most promising directions of testing and for identifying potential additive/synergistic effects. Multiphytoadaptogen (MPhA) containing 70 major phytocomponents of different chemical classes from 40 medicinal plant extracts has been studied in vitro, in vivo and in clinical researches. Antiproliferative and anti-tumor activities have been shown against some tumors as well as evidence-based therapeutic effects against age-related pathologies. In addition, the neuroprotective, antioxidant, antimutagenic, radioprotective, and immunomodulatory effects of MPhA were confirmed. Analysis of the PASS profiles of the biological activity of MPhA phytocomponents showed that most of the predicted anti-tumor and anti-metastatic effects were consistent with the results of laboratory and clinical studies. Antimutagenic, immunomodulatory, radioprotective, neuroprotective and anti-Parkinsonian effects were also predicted for most of the phytocomponents. Effects associated with positive effects on the male and female reproductive systems have been identified too. Thus, PASS and PharmaExpert can be used to evaluate the pharmacological potential of complex pharmaceutical compositions containing natural products.

The combinatorial topological analysis and modeling of self-assembly of the K78In160-hP238 (space group P-3m1, a = b = 17.211, c = 28.888 A, V = 7410 A3) and K8In11-hR114 (space group R-3c, a = b = 10.021 A, c = 50.891 A, V = 4426 A3) crystal structures are performed by computer methods (the ToposPro software package). Icosahedra In12 (with the -3m symmetry) are the templates on which three-layer clusters K130 = 0@12(In12)@30(In12K18)@86(K20In66) with the diameter of 17 A are formed. The two-layer cluster K66 formed on Friauf polyhedra K(K4In12) (with 3m symmetry) has a chemical composition of shells K@16(K4In12)@49(K16In33) and a diameter of 14 A. The K130 and K66 nanoclusters are framework-forming and involved in the formation of 2D layers A and B, respectively, thus forming a three-layer B–A–B package. The In12 clusters (with the -3m symmetry), In8 hexagonal bipyramids (with the 3m symmetry), and K spacer atoms are located in the voids of the layer of the K66 clusters. The three-layer package thickness corresponds to the value of the translation vector modulus c = 28.888 A. The framework structure is formed by linking the three-layer B–A–B packages in the [001] direction. The cluster precursor K17 = 0@In11K6 is installed for K8In11-hR114 in the form of a triangular In5 bipyramid on six faces of which In atoms are located with six bound potassium atoms. The microlayer is formed when the primary chains are bound in the (001) plane with a shift. The localization of the K spacer atoms takes place in the layer. The microframework of the structure is formed when the microlayers are bound with a shift.

Searching for buried ancient objects that have no traces on the surface as a result of plowing of the topsoil for centuries is a challenge for archaeology. In this paper, the use of geophysical methods for mapping necropolises is illustrated by a geophysical survey of the Shekshovo-9 burial site (Suzdal Opolie). The main idea is to detect archaeological objects using geophysical data, regarding them as heterogeneities against the background.

The article shows the implementation of the software for the selection of electronic intelligence at the stage of assessing the situation on the basis of theoretical studies conducted by the authors. It is indicated on the basis of which documents the assessment of the situation with the choice of electronic reconnaissance means is carried out, what stages this process consists of, what is needed for the selection of electronic reconnaissance means. The design of information flows of the program for the selection of electronic intelligence means at the stage of assessing the situation with the help of Data Flow Diagrams. The general block diagram of algorithm of work of the software of a choice of means of electronic reconnaissance at a stage of an assessment of a situation is constructed. On the basis of the conducted researches the database for storage of the list of means of electronic reconnaissance is developed. The prototype of the software for the selection of electronic intelligence means at the stage of situation assessment is implemented and examples of work on each of the main blocks are given in the form of screenshots, which were pre-designed in diagrams and block diagrams of algorithms. The advantages and disadvantages of the developed software for the selection of electronic reconnaissance means at the stage of situation assessment are determined. The further steps of research and improvement of the program of a choice of means of radio-electronic intelligence at a stage of an assessment of a situation are specified.

Leading industrial countries display the growth of paper industry even more than other industries. The paper is and was very important for our civilization. Technical industries also require the paper. The electro-technical, radio-technical industries use widely various kinds of paper for the production of things like cables, condensers, radio-diffusers, resistors, TV-sets and so on. In the chemical industry papers are used for chromatography, electrophoresis etc. But besides of clear advantages for simple usage there are some another advances for some usage namely materials which are resistant to mold fungi and the microorganisms. It is known that the least subject to the fungi effect are things what are consisted as linen fibers among all as well as sulfite and sulfate cellulose. The artificial fibers are more resistant than natural. Obviously the problem of conservation of already printed on paper materials growths more and more every year. Now it is strange when we can’t read old books which have not being saved in new digital formats. That is why the preserve the old paper literature in worthy state is so important for us and for future generations, and the problem of obtaining so called “biocide” material is so actual. It means such material which may destroy bacteria, mold fungi, and insects. In this work we have used the clays from Zakarpatiyan oblast Horbsky field. These clays are classified as bentonite type and have the following consistence with particular size is between 0,3 and 0,25 mm. The authors studied the sorption of latexes by basalt fibers. The following latexes were investigated: divinyl methyl methacrylate (DMMA), divinyl nitrile (SKN), isoprene nitrile (L-7). A method was used to recharge the surface of cellulose fibers to obtain a flexible, durable filter material. We checked the resistance of materials to mold.

The problem of modern archeology is the study of monuments that are not expressed on the surface due to centuries of plowing. Using the example of a geophysical study of the Shekshovo 9 monument (Suzdal Opolie region), we consider the use of geophysical methods for mapping the structure of the necropolis. The main idea is to search and interpret archaeological objects in geophysical data as heterogeneities towards background geological and soil structures.

Aesthetics is one of the key elements that accompanies modern medicine, in particular, dentistry. The need for treatment not only eliminates the symptoms of the disease but also leads to the restoration or improvement of the aesthetic appearance of the person, and especially the face, gave impetus to the development of new areas of science and technology. An important step in the implementation of such treatments is experimental research to identify the norm for certain categories of the population, primarily according to sex and ethnic group. The aim of the study was to establish the characteristics of cephalometric parameters in Ukrainian young men and young women with orthognathic occlusion, which usually do not change during surgical and orthodontic treatment, depending on sex and facial types. On the basis of the clinic "Vinintermed" teleroentgenography was performed using a dental cone-beam tomograph Veraviewepocs 3D Morita (Japan). Cephalometric examination of lateral teleroentgenograms in 46 young men (aged 17 to 21 years) and 72 young women (aged 16 to 20 years) with orthognathic occlusion was done. The type of face was determined according to the morphological index of Garson. The evaluation of parameters that usually do not change during surgical and orthodontic treatment was performed in the licensed package "Statistica 6.0" using non-parametric methods of evaluation of the results. The percentile ranges of cephalometric parameters, which usually do not change during surgical and orthodontic treatment depending on the facial types of Ukrainian young men and young women with orthognathic occlusion has been established. Pronounced manifestations of sexual dimorphism of cephalometric parameters, which usually do not change during surgical and orthodontic treatment (higher values in young men) are established only for most linear dimensions (values of distances NS, Ar-Go, N-Se, N-CC, P-PTV and S-Ar) in representatives of different types of faces. Both between young men and young women with different face types, there are almost no reliable or tendencies of differences in cephalometric parameters, which usually do not change during surgical and orthodontic treatment.

The article discusses the use of virtual reality technologies in the school informatics course in teaching modeling. The greatest attention is paid to methodological recommendations for the elective course "Technologies of multidimensional modeling based on a virtual reality system for a smart home". In the classroom, students get acquainted with the basic concepts related to virtual reality, modeling objects and processes in 3D editors and based on a modern game engine. For students in the lesson, it is proposed to work with additive technologies on the example of studying a 3D printing device using virtual reality technology. Students participate in all stages of designing and developing a model in the cloud environment and then printing it on a 3D printer. Training within the elective course ends with a consideration of the basic concepts of the internet of things, the possibilities of augmented reality technologies in this area and the construction of a smart device using an educational kit.

The origin of pain in jaundiced patients with the cancer of the pancreatobiliary zone and chronic pancreatitis hasn’t been entirely studied yet. The aim of the study was to assess the effect of cholemia on the severity of pain syndrome in patients with surgical pathology of the pancreas. The results of surgical treatment of 54 patients with chronic pancreatitis and 218 patients with pancreatobiliary cancer complicated by obstructive jaundice were analyzed. In these patients pancreatoduodenal resection was performed. The main group patients (112 patients) have been prepared to surgery by combination of conservative measures for express detoxification and decompression of the biliary tract. The control one (160 patients) – only conservatively. The severity of pain syndrome was assessed using a visual analogue scale. In main group, the initial level of total bilirubin was 274.3±5.9 μmol/L, direct – 211.2±2.2 μmol/L, indirect – 63.4±2.6 μmol/L. In the control group – 270.6±4.6 mmol/L, 206.3±2.4 mmol/L and 64.1±2.6 mmol/L. The intensity of pain syndrome on admission was 4.9±0.4 and 5.7±0.2 points in the main and control groups, respectively. Due to the preoperative preparation, there was a slight decrease in the intensity of pain according to the visual analogue scale (4.5±0.4 points in the main and 5.4±0.3 points in the control group). In the main group, the intensity of pain decreased, respectively, from 6.4±0.3 through 5.1±0.4 to 2.8±0.4 points. In the control group – from 8.6±0.4 through 6.7±0.5 to 3.1±0.2 points. A strong positive correlation between the intensity of pain syndrome and the level of cholemia was determined (r = 0.74 in the main and r = 0.79 in the control groups).

Based on the available geological and geodetic data, it has been established that the structures of the Alpine–Himalayan–Indonesian mobile belt are oroclinally (horseshoe-shaped) closed at its western and eastern extremities. In the west, from the Atlantic Ocean, this closure is represented by the Bet–RIF arc and, in the east, from the Pacific Ocean, by the Band and Mindanao arcs. The presence of these closures means there is no structural connection between the mobile belt under discussion and the Atlantic and Pacific oceans, respectively. Thus, the existing plate-tectonic reconstructions, according to which the Tethys paleocean was a wide bay of the Pacific Ocean connected in the west with the Atlantic Ocean (wide Tethys), are in opposition to the facts. The Alpine–Himalayan–Indonesian mobile belt has to be considered an epigeosynclinal rather than an epioceanic structure.

This paper proposes a method of obtaining the first representative of a polymeric proton-conducting medium with protic ionic groups in the main chain of a polymer by the mutual neutralization of linear telechelic oligomers with end groups of the basic and acidic nature. Oligoethylene oxide containing 1-(3-aminopropyl) imidazole fragments with two types of basic centers (aliphatic secondary amine groups and imidazole fragments) at the ends of the chain was used as the oligomer with basic properties. Sulfonic acid-terminated oligoethylene oxide was used as the acid oligomer. Protonation of aliphatic secondary amino groups in the composition of the oligomer of the basic type with the formation of an ion-elongated polymer chain is more probable at the equimolar ratio of the starting compounds according to the analysis of ΔKa values. It is shown that the synthesized polymer contains two types of crystalline formations with melting points of 37.6 °C and 46.2 °C and turns into a liquid state, when heated to higher temperature values. The proton conductivity of the polymer under anhydrous conditions is close to the conductivity of the initial sulfonic acid-terminated oligomer in the temperature inter val of 40-100 °C and reaches 2.3 · 10–4 S/cm at 100 °C, despite a much lower content of proton charge carriers.

The aim was to assess the effect of hyperbilirubinemia on the severity of pain syndrome in patients with pancreatobiliary cancer during perioperative period.Materials and methods. The results of surgical treatment of 218 patients with pancreatobiliary cancer complicated by the development of mechanical jaundice syndrome, who underwent pancreatoduodenal resection, were analyzed. The severity of pain was assessed on a visual-analog scale, as well as subscales of questionnaires EORTC QLQ-C30 and SF-36.Results. At the time of admission to the hospital the initial level of total bilirubin was 274.3 ± 5.9 μmol/L, direct - 211.2 ± 2.2 μmol/L, indirect – 63.4 ± 2.6 μmol/L. The intensity of pain syndrome on admission was 4.9 ± 0.4 points. In the early, late and late postoperative period the intensity of pain decreased, respectively, from 6.4 ± 0.3 to 2.8 ± 0.4 points.Conclusions. A strong positive correlation between the intensity of pain syndrome and the level of cholemia was determined (r = 0.74)., Цель работы – оценка влияния гипербилирубинемии на интенсивность болевого синдрома у больных раком панкреатобилиарной зоны в течение периоперационного периода.Материалы и методы. Проанализированы результаты хирургического лечения 218 больных раком панкреатобилиарной зоны, осложненного развитием синдрома механической желтухи. Пациентам выполнена панкреатодуоденальная резекция. Выраженность болевого синдрома оценивали по визуально-аналоговой шкале, а также с использованием субшкалам опросников EORTC QLQ-C30 и SF-36.Результаты. На момент поступления в стационар у пациентов уровень общего билирубина составил 274,3 ± 5,9 мкмоль/л, прямого – 211,2 ± 2,2 мкмоль/л, непрямого – 63,4 ± 2,6 мкмоль/л. Интенсивность болевого синдрома на момент поступления в стационар составила 4,9 ± 0,4 балла. В раннем, позднем и отдаленном послеоперационном периодах интенсивность боли соответствии уменьшалась с 6,4 ± 0,3 до 2,8 ± 0,4 балла.Выводы. При сопоставлении интенсивности болевого синдрома и уровня холемии определена сильная положительная корреляционная связь (r = 0,74)., Мета роботи – оцінювання впливу гіпербілірубінемії на вираженість больового синдрому у хворих на рак панкреатобіліарної зони протягом періопераційного періоду.Матеріали та методи. Проаналізували результати хірургічного лікування 218 хворих на рак панкреатобіліарної зони, що ускладнений розвитком синдрому механічної жовтяниці. Пацієнтам виконали панкреатодуоденальну резекцію. Вираженість больового синдрому оцінювали за візуально-аналоговою шкалою, а також застосовуючи субшкали опитувальників EORTC QLQ-C30 і SF-36.Результати. На момент надходження у стаціонар у пацієнтів рівень загального білірубіну становив 274,3 ± 5,9 мкмоль/л, прямого – 211,2 ± 2,2 мкмоль/л, непрямого – 63,4 ± 2,6 мкмоль/л. Інтенсивність больового синдрому на час надходження у стаціонар становила 4,9 ± 0,4 бала. У ранньому, пізньому та віддаленому післяопераційному періодах інтенсивність болю відповідно зменшувалася з 6,4 ± 0,3 до 2,8 ± 0,4 бала.Висновки. Зіставляючи інтенсивність больового синдрому та рівень холемії, встановили сильний позитивний кореляційний зв’язок (r = 0,74).

Biocides are widely used in medicine and various industries to protect against a number of harmful microorganisms. Organic quaternary ammonium and guanidine-containing compounds, the biological action of which is based on membrane-toxic properties, are used as bactericidal preparations. The aim of this work was to study the bactericidal and fungicidal activities of the synthesized oligomeric alkylsubstituted guanidinium bromides with different radicals -C3H7, -C7H15, -C10H21, against different isolates of heterotrophic bacteria and microscopic fungi. Methods. The synthesis of alkyl-substituted guanidiniumcontaining oligomers was performed in two stages. In the first stage, alkyl-substituted guanidine was obtained by the reaction of guanidine, previously converted by alkali from the salt form to the base form by the base and alkyl bromides (Alk=-C3H7 (propyl), -C7H15 (heptyl), -C10H21 (decyl)) in methanol at a temperature of 50°C and a molar ratio of 1:1. The second carried out the reaction between aromatic oligoepoxide DER-331 and alkyl-substituted guanidine in methanol at a temperature of 50°C for 2–3 hours and a molar ratio of 1:2. Bacteria were grown on meat-peptone agar for 48 hours at a temperature of 28±2°С. Test cultures of micromycetes were cultured on agar beer wort (6°B), incubated for 14 days in a thermostat at a temperature of 28±2°C. Antimicrobial activity of newly synthesized alkyl-substituted guanidinium-containing oligomers was determined by standard disco-diffusion method (method of disks on agar) and fungicidal activity was determined by the method of holes in agar. Results. Oligomeric alkylsubstituted guanidinium bromides with different radicals composed -C3H7, -C7H15, -C10H21- synthesized by the reaction of guanidine alkyl bromides with aromatic oligoepoxydes. It was found that alkyl-substituted guanidinium-containing oligomers at a concentration of 1–3% inhibited the growth of Escherichia coli 475, Pseudomonas aeruginosa 465, Klebsiella pneumonia 479, Pseudomonas pseudoalcaligenes 109, Staphylococcus aureus 451, E. faecalis 422, Rhodococcus erythropolis 102, Bacillus subtilis 138 and most of the studied micromycetes – Aureobasidium pullulans F-41430, Paecilomyces variotii F-41432, Penicillium funiculosum F-41435, Penicillium ochrochloron F-41431, Scopulariopsis brevicaulis F-41434, Trichoderma viride F-41437, Candida albicans F-41441, Aspergillus flavus F-41442, Aspergillus niger F-41448, Penicillium sp. F-41447. Conclusions. Antimicrobial and fungicidal properties significantly depend on the length of the alkyl radical, with increasing of its length the diameter of the zone of bacterial and micromycetes growth retardation increases.10.15407/microbiolj82.06.054

The possibilities of tandem mass spectrometry have been studied for the technology of analyzing aralosides in the pharmaceutical composition of Multifitoadaptogen (MFA) and extract of the roots of Aralia mandshurica (which is an ingredient in MFA). Chromatography is performed on an ACQUITY UPLC BEH C18 column in gradient mode. A TSQ Vantage electrospray ionization triple quadrupole mass spectrometer is used. In MFA, as well as in the extract of the roots of Aralia mandshurica, Aralosides A, B, C, and/or their isomers are identified.

Using computer methods (the ToposPro software package), the combinatorial-topological analysis and modeling of self-assembly of the crystal structure of Li36Ca4Sn24-oS64 (space group (sg) Cmcm, a = 4.640 A, b = 27.112 A, c = 11.491 A, V = 1445.5 A3) and LiMgEu2Sn3-oS28 (sg Cmcm, a = 4.782 A, b = 20.717 A, c = 7.743 A, V = 767.1 A3). For the Li36Ca4Sn24 intermetallic compound a new type of 11-atom cluster K11 is installed, formed from double pentagonal rings: K11 = 0@11 (Li5)Ca(Sn5). The maximum cluster symmetry K11 and primary strand of translationally related K11 clusters corresponds to noncrystallographic symmetry 5m. Primary chains of linked K11 clusters preserving only symmetry m are located in the direction [100] and the distance between the centers of the clusters determines the length of vector a = 4.640 A. The layer is formed when the primary chains located antiparallel are bound. The tetrahedral clusters are located between the primary chains K4 = 0@4 (Li3Sn), forming chains in the direction [100]. The symmetry and topological code of the self-assembly processes of the 3D structure of the LiMgEu intermetallic compound LiMgEu2Sn3-oS28 is reconstructed from clusters K4 = 0@4 (LiMgEuSn) and K3 = 0@3 (Sn2Eu). The layer is formed when the parallel chains of K4 + K3 are bound.

This article presents the results of microcalorimetric studies of the process of the interaction of the hydration products of Portland cement with additives of glass powders of various chemical compositions. It is found that when glass is added in a powder state, an increase in the rate of hydration of Portland cement is observed.

Using computer methods (ToposPro software package), the geometrical and topological analysis of the crystal structure of the Zr6Mg20Zn128-cP154 intermetallic compound with cubic cell parameters a = 13.709 A, V = 2576.42 A3, and space group Pm-3 is carried out. Two new nanocluster precursors with the ‑43m symmetry are determined: a three-layer K136 nanocluster of the 0@Zn12@32(Mg20Zn12@92(Zr12Zn80) composition with an internal icosahedron 0@Zn12 and 12 Zr atoms and 20 Zn atoms in 60-atomic Zn-shell and a two-layer K30 nanocluster of the 0@Zn6@Zn24 composition with an internal Zn6-octahedron and 24 Zn atoms in the external shell. The symmetrical and topological codes of the self-assembly processes of 3D structures from K136 and K30 nanocluster precursors are reconstructed in the following form: primary chain → microlayer → microframework. The Zn2 dimers are determined as the spacers occupying the voids in the 3D framework from K136 and K30 nanoclusters.

Using computer methods (ToposPro software package), geometrical and topological analysis of the crystal structure of Na52Ba4Sn80-cF540 intermetallic compound (a = 25.053 A, V = 16 010.82 A3, space group F-43m) are carried out. Two new nanocluster precursors with the -43m symmetry are determined, more specifically, the K47 two-layer nanocluster of the Na@16Sn@30Na composition with an NaSn16 internal Friauf polyhedron and 30 Na atoms in the shell and a K64 two-layer nanocluster of the 0@8(Sn4Ba4)@56(Na4Sn52) composition with the Sn4Ba4 internal polyhedron and 56 (4Na + 52Sn) atoms in the shell. The symmetrical and topological codes of self-assembly processes of 3D structures from K64 and K47 cluster precursors are reconstructed in the following form: primary chain → microlayer → microframework. The Na4 and Sn8 clusters with the -43m symmetry and Na atoms are determined as the spacers occupying the voids in the 3D framework from the K64 and K47 nanoclusters.

This paper proposes ideas based on triply periodic surfaces of the minimum energy. A large number of structures can be described by a limited number of minimal surfaces. There is a certain connection between the symmetry of the surfaces, space groups, and structures.

Постановка проблеми. Сучасні енергетичні установки та авіадвигуни працюють за підвищених температур. Якщо в перших газотурбінних двигунах (ГТД) робочі температури матеріалу становили від 600 до 900 °С, то в подальшому значно підвищилися, досягнувши наразі 1 700 °С.Для забезпечення роботи за високих температур застосовують жаростійкі покриття на основі нікелю. Ресурс лопаток у першу чергу залежить від якісних показників нанесених покриттів (рівномірності, відсутності пор, включень, хімічної однорідності). Якість нанесення покриттів визначається режимами нанесення і якістю самого катода. Як правило, катоди являють собою сплави, що наносяться зі спеціальною геометрією. Існує кілька технологій виготовлення катодів, кожна з яких має свої переваги і недоліки. Один із методів − пошарове формування сплавом зливків для виготовлення катодів у мідному водоохолоджуваному кристалізаторі із застосуванням електрода, що плавиться. Мета дослідження − підвищення якості катодів на основі нікелю (Ni − Cr − Al − Y) шляхом удосконалення технологічних режимів виплавки зливків. Завдання − зменшення загальної кількості дефектів у зливках у вигляді несуцільностей, пор, непроплавів, підвищення гомогенності структури і хімічного складу. Методика.Вдосконалено обладнання, зокрема, вакуумно-дугова установка була доукомплектована рампою і балоном із гелієм. Отримані пробні зразки у вигляді «шайб» (діаметром 127 мм і товщиною 40 мм), які використовувалися для дослідження мікроструктури і хімічного складу. Відпрацьовано режими переплаву. Дослідження хімічного складу проводили із застосуванням багатоцільового растрового електронного мікроскопа РЕМ 106І, оснащеного системою мікроаналізу. Наукова новизна. Визначено залежність впливу концентрації суміші газів (аргон − гелій), що дозволило отримати оптимальне співвідношення захисних газів. При співвідношенні газів 70/30 % отримано максимально якісні катоди, на яких проводили подальші дослідження. Висновки. На підставі результатів досліджень впливу концентрації суміші газів на структуру та склад катодів установлено технологічні режими плавлення, що дозволило поліпшити показники якості та економічні показники досліджуваних катодів. Це зменшить кількість браку катодів, поліпшить працездатність деталей з покриттями та ресурс авіаційних двигунів у цілому.

Background. Polyhexamethylene guanidines are widely used as biocides and disinfectants due to the wide range of their antimicrobial activity against Gram-positive and Gram-negative bacteria, viruses, fungi, and molds. The mechanism of biocidal action of polyguanidines is similar to that of quaternary ammonium compounds and has a membrane toxic nature. The advantages of polyhexamethylguanidines salts include their moderate toxicity and a lack of cumulative action against living organisms. The convenience of such polymeric biocides lies in their high water solubility and in the absence of volatility, which allows disinfectant work to be carried out in the presence of people. It is known that the introduction of alkyl radicals into the polymer chain leads to an increase in the bactericidal and fungicidal action of the obtained compounds. In order to enhance these properties, it seems promising to obtain polyetherguanidines with alkyl radicals in their structure. The aim of this work was to study the fungicidal and bactericidal activity of synthesized alkyl-substituted polyetherguanidinium iodides against a number of bacteria and microscopic fungi. Methods. Bacteria were grown on the meat-peptone agar for 48 hours at 28±2 °C. Test cultures of micromycetes were cultured on agar beer wort (6 ° B), incubated for 14 days at 28±2 °C. Antimicrobial and fungicidal activities of the newly synthesized alkyl-sub­sti­tuting polyetherguanidines were determined by the standard disco-diffusion method. Results. The synthesis of polyetherguanidinium iodide is carried out in four stages. The first stage is the synthesis of a guanidine-containing oligoether with terminal guani­dine moieties by the reaction between aromatic oligoepoxide and guanidine. The second stage is the synthesis of polyetherguanidinium chloride by the reaction between guanidinium-containing oligoether with terminal guanidine fragments and oligooxyethylenediamine of different molecular weight. In the third stage, the obtained polyetherguanidinium chloride is converted from the salt form to the base form by the reaction with an equivalent amount of alkali in ethanol. In the fourth stage, the basic polyetherguanidine is reacted with methyl iodide at a molar ratio of polyetherguanidine: methyl iodide components of 1:2. The bactericidal and fungicidal activities of alkyl-containing polyetherguanidinium iodides against various heterotrophic bacteria and microscopic fungi has been shown. It was found that polyetherguanidinium iodides at a concentration of 1–3% inhibited the growth of Gram-negative (Escherichia coli 475, Klebsiella pneumonia 479) and Gram-positive (Staphylococcus aureus 451) bacteria. The obtained alkyl-containing polyetherguanidinium iodides at a concentration of 1% for 14 days showed fungicidal activity in almost all studied isolates. With an increasing length of the oligoethylene oxi­de component, the obtained polymers with n = 10 and 50 did not show a fungicidal effect against Aspergillus niger, and the polymer with n = 50 – against the micromycete Aspergillus versicolor. If we determine the fungicidal effect as a whole, the polymer with n = 6 had the highest activity against all studied isolates after 14 days, while the fungicidal effect of polymers with n = 10 and n = 50 tends to decrease. All synthesized alkyl-containing polyetherguanidinium iodides showed the highest activity against such microscopic fungi as Cladosporium cladosporioides, Acremonium strictum, Alternaria alternate, Cladosporium sphaerospermum, Paecilomyces variotii, Stachybotrys chartarum. Also noteworthy is the selective effect of the obtained polymers on individual isolates. Conclusions. The obtained polyetherguanidinium iodides of different molecular weight at a concentration of 1–3% showed bactericidal activity against Staphylococcus aureus 451, Escherichia coli 475, Klebsiella pneumoniae 479 and fungicidal effect against all fungi studied by us and can be used as disinfectants for indoor treatment.

The geometric and topological analyses of the K44In80-hR366 (space group R $$\bar {3},$$ a = b = 17.214 A, c = 44.612 A) and K34In82-cF464 (space group Fd $$\bar {3}$$ m, a = 24.241 A, V= 14244.64 A3) crystal structures are implemented by computer-based methods (ToposPro program). The framework-forming 142-atom icosahedral nanocluster K142 is determined by the method of the complete decomposition of the 3D atomic network of the K44In80 intermetallide into cluster structures. The K142 nanoclusters with the symmetry $$\bar {3}$$ are three-layer with the shell composition of 0@12In@32(K26In6)@98(K26In72). The first two shells form the Bergman cluster. The third shell of 98 atoms is formed by 5-, 6-, and 7-atom rings (554.638.76) and contained 98 apexes, 270 edges, and 174 faces. The K142 nanoclusters form closely packed two-dimensional layers 36 located with a shift along [001]. The distance between the K142 cluster centers determines the translation vector value ahex = 17.214 A. Voids in the 3D framework are occupied by 0@K6In2 spacers. Suprapolyhedral clusters K141 with the symmetry –43m comprising four Bergman clusters 0@12In@32 (K20In12), each of which have the symmetry $$\bar {3}$$ m, are formed in the K34In82 intermetallide. Voids in the 3D framework are occupied by In(In4) spacers in the form of tetrahedra with the central atom In, which have the symmetry of –43m. For the K44In80 and K34In82 intermetallides, the symmetric and topological code for the self-assembly processes of the 3D structure from nanocluster precursors K142 and K141 is determined in the following form: primary chain → layer → framework.

Biodegradation of various materials in the environment is important because many synthetic materials are stable for a long time. At the end of the service life, the materials must be involved in the natural cycle and decompose. In modern polymer chemistry, one of the promising areas is to obtain and study the properties of hydrogel systems, among which a significant place is occupied by polyethylene oxide hydrogels. The aim of the study was to determine the biodegradation of guanidine-containing polyethylene oxide hydrogel under the action of bacteria and to study its antimicrobial properties. The antimicrobial activity of a guanidine-containing oligomer and its newly synthesized polyethylene oxide hydrogel was studied by a disco-diffusion method. The enzymatic activities of bacteria were determined by spectrophotometry. To study the resistance of guanidine-containing polyethylene oxide hydrogel to microbial destruction, bacteria were grown in Tauson's liquid medium with the addition of meat peptone broth at a temperature of 28±2 °C. Changes in the chemical composition of the studied materials were analyzed by infrared Fourier spectroscopy of the Tensor 37 (Bruker) and 1H NMR spectroscopy. The antimicrobial properties and biodegradation of guanidine-containing polyethylene oxide hydrogels were determined, which were obtained by reacting oligooxyethylene glycol MW 6000 with toluene diisocyanate and guanidine-containing oligomer, which acted as a crosslinking, ion-containing and antibacterial-agent. The synthesized hydrogel showed antimicrobial activity against gram-positive and gram-negative bacteria. The biodegradation of hydrogels under the action of various bacterial strains and enzymes that they synthesize was studied. The presence of the tested materials lead to a decrease in the enzymatic activity of bacteria in 1.4 – 2.5 times compared with the control. Synthesized guanidine-containing polyethylene oxide hydrogel showed antimicrobial activity against the studied test cultures. The introduction of the studied materials into Tauson's environment as additional sources of carbon and energy helped to reduce the catalase and lipase activities of hydrocarbon-oxidizing bacteria. Under the influence of the studied bacteria, the hydrogels were destroyed with 88.4% from the initial value.

The combinatorial-topological analysis and simulation of self-assembly of the Na96Hg36-hR132 (space group R-3c, a = b = 9.228 A, c = 52.6380 A, V = 3881.91 A3) and Na12Hg8-tP20 (space group P42/mnm, a = b = 8.520, c = 7.800 A, V = 566.2 A3) crystal structures are conducted by computer-based methods (ToposPro program package). Polyhedral cluster precursors K11 = 0@11(Na8Hg3) and K9 = Hg@Na8 are first determined for the intermetallic compound Na96Hg36-hR132, while polyhedral cluster precursors K5 = 0@Na3Hg2 are determined for the intermetallic compound Na12Hg8-tP20. The symmetry and topology code of the self-assembly processes of the 3D structure Na96Hg36-hR132 from the nanocluster precursors K11 and K9, and of the 3D structure Na12Hg8-tP20 from the K5 clusters are reconstructed as the primary chain $$S_{{\text{3}}}^{1}$$ → layer $$S_{{\text{3}}}^{2}$$ → frame $$S_{{\text{3}}}^{3}.$$ The structural analysis of all known intermetallic compounds is conducted, and numerous examples of the assembly of their structures from the K5, K9, and K11 clusters are found.

This paper considers our experience in applying the structural technique to evaluating the reliability of a therapeutic robotic set designed for guided radiation exposure of malignant tumors in patients. The features of the structural decomposition of the electromechanical systems of the gamma unit and treatment table are distinguished. The results of applying the Relex software set in drawing structural function charts and calculating the reliability levels of complex objects are presented.

Настоящая статья посвящена анализу эволюции концепта «America» на примере номинативной парадигмы американского фотографического дискурса. Авторы полагают, что практическая значимость настоящей статьи заключается в возможности использования результатов исследования на занятиях по практическому иностранному языку и американистике посредством полного «погружения» обучающихся в лингвокультурную картину мира Соединенных Штатов Америки благодаря таким характеристикам американских фотографий, как наглядность и аутентичность. Актуальность данного исследования обусловлена необходимостью изучения влияния, оказываемого американским фотографическим дискурсом на художественную и социально-политическую сферы жизни общества. Цель статьи заключается в исследовании конституентов концепта «America» в динамике с точки зрения лингвосинергетического подхода, предполагающего наблюдение за динамикой языковой системы на протяжении продолжительного периода времени. Авторы рассматривают особенности американского фотографического дискурса как сложного коммуникативного явления, анализируют взаимодействие и взаимовлияние живописи и фотографии в рамках американской художественной традиции. В работе также исследуется структура и семантические особенности макроконцепта «America», анализируются микроконцепты «Area», «Human», «Architecture», «Environment», «History», «Culture», с помощью которых происходит актуализация макроконцепта «America». Авторы приходят к выводу, что номинативная парадигма американского фотографического дискурса отличается наличием антропоцентричности, заинтересованности фотохудожников в новых объектах («Hi-Tech», «Human» / «Nude»), поиске новых форм художественной фотографии. Эволюция номинативной парадигмы выражается в снижении количественных показателей репрезентантов концептов «Racism» и «The Great Depression» вследствие объективных социально-исторических факторов.

The species composition, frequency of occurrence, and the abundance of phytohelminths in communities of soil nematodes in natural ecosystems of the Left-Bank Polissia (Chernihiv region) were studied. Samples were collected throughout 2011-2016 in forest and meadow ecosystems on the territory of Chernihivskyi, Horodnianskyi, Kozeletskyi, Koropskyi, Menskyi, Ripkynskyi, Sosnytskyi, Semenivskyi, Shchorskyi and Novhorod-Siverskyi districts. Nematodes were extracted by a modified Baermann’s method from the 20-g sample. The exposition time was 48 h. Extracted nematodes were fixed in the triethanolamine–formalin (TAF, 2 % triethanolamine, 7 % formaldehyde solution, 91% water), and mounted on the temporary hydroglyceric slides. Nematode abundance was expressed as specimens per 100 g of dry soil. Seventeen species from three orders, ten families and fifteen genera were found. Eleven species (64.7 % of the species composition) belonged to the order of Tylenchida, four (23.5 %) – Triplonchida, two (11.8 %) – Dorylaimida. Eleven species (Gracilacus audriellus, Paratylenchus nanus, Tylenchorhynchus dubius, Helicotylenchus dihystera, Macroposthonia annulata, Diphtherophora communis, Trichodorus primitivus, Paratrichodorus teres, Paratrichodorus pachydermus, Longidorus elongatus, Xiphinema index) are ectoparasites, three species (Ditylenchus dipsaci, Pratylenchus pratensis, Hirschmaniella gracilis) – endoparasites, and three species (Hemicycliophora sp., Heterodera sp. 1, Heterodera sp. 2) – semiendoparasites. Phytohelminths in communities of soil nematodes in forest ecosystems ranged from 9.4 to 26.3 %. But in meadow ecosystems of the Mezin National Nature Park it was a dominant group (proportion in the community 47%). The most frequent species were G. audriellus, H. dihystera and T. dubius which occurred in 33.3 %, 33.3 % and 28.3 % of samples respectively. P. nanus, D. dipsaci, P. pratensis та D. communis – had frequency of occurrence 15 – 20%. Ten species of phytohelminths were found in 1–4 ecosystems (1.7–6.7%). G. audriellus and H. dihystera were abundant (124 and 56 specimens per 100 g of soil respectively).

Congratulations to the Executive Secretary of the Russian Journal of Philosophical Sciences Avrora A. Pruzhinina on Her 75 th Birthday.

The TOPOS software package is used for the combinatorial topological analysis and simulation of the self-assembly of the K52Na12Tl36In122-hP224 (spatial group P-3m1, a = b = 16.909, c = 28.483 A, V = 7 052 A3) crystalline structure. A total of 1649 variants of the cluster representation of a 3D atomic lattice with the number of structural units ranging from 4 to 10 are found. Two frame-forming three-layer icosahedral nanoclusters are detected: K132 and K116 with symmetry g = –3m and a diameter of 17 A. The chemical composition of the shells of the three-layer 132-atom nanocluster K132 is 0@12(In6Tl6)@30(In6Na6K18)@90(In72Na12K6) and that of the 116-atom nanocluster K116 is (0@12(In6Tl6)@26(In12K14)@78(In36Tl20K12). The symmetrical and topological code of the self-assembly of the 3D Na12K52Tl36In122 structure from the precursor K132 and K116 nanoclusters is reconstructed in the following form: primary chain → layer → frame. The framework’s voids are occupied by spacer atoms K and Tl.

Aim. The study objective was to examine fibrin monomer hemostatic effects in post-traumatic parenchymal hemorrhage in the setting of pharmacologically associated platelet aggregation inhibition. Materials and methods. In the in vivo experimental study on male rabbits, the hemostatic effects of fibrin monomer (FM) (0.25 mg/kg) were evaluated in comparison with tranexamic acid (TA) (15 mg/kg) in post-traumatic parenchymal hemorrhage against the background of preliminary inhibition of platelet aggregation function with acetylsalicylic acid (2.0 mg/kg) and clopidogrel (8.0 mg/kg). Volume and rate of blood loss were estimated, as well as the parameters of the hemostatic system. Results. It has been established that FM versus placebo when administered intravenously 1 hour before the injury can prevent severe bleeding associated with taking antiplatelet agents. The volume of blood loss after FM administration decreased in median by 6.0 times, the rate of blood loss – by 5.9 times, and when using TA – by 2.4 (Р FM -TA < 0.02) and 4.8 times respectively. The hemostatic effects of TA were realized when the hemostatic balance was shifted towards the increased fibrin formation (an increase in the level of D-dimer in the blood plasma). The use of FM was not accompanied by any significant changes in the blood coagulation system. Conclusion. The fibrin monomer at a dose of 0.25 mg/kg i.v. is capable of preventing severe posttraumatic parenchymal bleeding caused by the combined use of drugs with different antiplatelet action. The phenomenon is not completely clear and needs to be analyzed in further research. The mechanism of hemostatic effects associated with FM is currently being studied.

Necessary precursors for obtaining tritium-labeled Z-Gly-Pro-DOPA, Z-Gly-Pro-SRT, Z-Gly-Pro-Dox, OL-Gly-Pro-DOPA,Ol-Gly-Pro-Srt were synthesized for the first time (Gly stands for glycine; Pro, proline; Ol, Oleic acid, DOPA, dopamine; Dox, Doxorubicin; Srt, Serotonin; and Z, benzyloxycarbonyl protection). The tritium-labeled proline and glycine were used to synthesize peptide derivatives of DOPA, Dox, and Srt with different tritium distributions.

—Based on the distribution of mantle seismicity and the sets of focal mechanisms of the earthquakes, the existence and deformation type of an allantoid mantle body within the eastern part of the Caucasus Isthmus is established. The body is inclined and plunges from the southeast to the northwest to a depth of 160 km. The shape of the mantle body and the type of its stress state which is fundamentally different from that for the Earth’s crust in the region precludes us from accepting plate-tectonic interpretation of this formation in the form of a concept implying the subsidence of the subducting part of the Arabian lithospheric plate underneath the Eurasian plate. We hypothesize that this phenomenon is associated with the tectogenesis process developing in the subcrustal mantle of the Caucasus irrespective of the collision processes.

Precursors were synthesized for the first time for obtaining tritium-labeled Вос-Gly-Pro-DOPA, Вос-Gly-Pro-Srt, LА-Gly-Pro-DOPA, LА-Gly-Pro-Srt, Вос-Pro-DOPA, Вос-Pro-Srt, Вос-Gly-Pro-Dox, LА-Gly-Pro-Dox, Вос-Pro-Dox. Tritium is introduced by using dehydroproline derivatives N-protected by a tert-butyloxycarbonyl group or lauric acid. The suggested approach made it possible to obtain labeled compounds in high yield with high molar radioactivity. A new procedure is suggested for purification of water-insoluble compounds by solid-phase extraction.

Glioblastoma multiforme (GBM), a grade IV astrocytoma, is the most common and deadly type of primary malignant brain tumor, with a patien’s median survival rate ranging from 12 to 15 months. Over the last fifteen years, the treatment for GBM has included maximal safe surgical resection with combination radiotherapy and adjuvant temozolomide chemotherapy. The low efficacy of mentioned therapies has forced researchers to explore an appropriate alternative or complementary treatment for GBM. It has been shown that curcumin has therapeutic potentials to fight against GBM via affecting on cell proliferation, apoptosis, cell cycle, invasion and angiogenesis pathways. In addition, curcumin possess a synergistic impact with chemotherapeutic agents. Herein, we summarized the current findings on curcumin as potential therapeutic agent in the treatment of GBM.

Nanocomposites based on ED-20 epoxy resin and single-walled carbon nanotubes (SWCNT) with high aspect ratios (l/d ~ 2500) have been produced. The filler has been introduced into a matrix using a high speed mixer without solvents. The electrical and physical characteristics of produced composites have been examined at various SWCNT concentrations. A low percolation threshold is experimentally established, indicating weak filler agglomerates in the epoxy matrix. The dielectric permittivity and tangent loss are plotted as the functions of the SWCNT concentration within a wide frequency range. All dependences exhibit the presence of a relaxation peak shifting toward the higher frequencies as the filler concentration increases. The investigation of nanocomposite cleavages via scanning electron microscopy reveals a uniform SWCNT distribution in the matrix.

A procedure was developed for introducing tritium into the side chain of the abscisic acid (ABA) molecule. The reaction was carried out in dioxane in the presence of the Lindlar catalyst. The yield of the labeled product was 70% and the molar radioactivity was 44 Ci/mol. The tritium-labeled abscisic acid analogue was found to be a growth substrate for soil bacteria that incorporate a radioactive label into cellular metabolites. The absorption of the label by bacteria from the side chain of abscisic acid is more than an order of magnitude higher than that for labeling in the cyclohexene moiety. The results indicate the existence of a previously unknown metabolism pathway of ABA in microorganisms.

An ellipsometric method is used to study the optical properties of unoxidized surfaces of polycrystalline ytterbium film in the spectral range of 0.4–2.6 mm. The measured refractive indices and absorption coeffi cient of the film are used to calculate the dispersion dependences of the optical conductivity σ reflectivity R, the imaginary and real parts of the dielectric constant e1 and e2, and the characteristic electron energy loss functions Im(e–1). The infrared measurements are used in a two-band model for the conductivity to calculate the electronic characteristics of ytterbium in the solid and liquid states.

Thermokarst (thaw) lakes of the Western Siberian Lowland (WSL), the World´s largest permafrost peatland, contain important but poorly constrained stocks of organic carbon (OC) and nitrogen. These lakes are highly vulnerable to climate warming and permafrost thaw. The present work aims to quantify the OC and total nitrogen (TN) stocks and accumulation rates in sediments of 11 thermokarst lakes in the WSL across a permafrost gradient, from isolated to discontinuous and continuous permafrost. We found an increase in OC and TN stocks in lake sediments (0–30 cm) from the northern taiga with sporadic permafrost (285 Tg C and 10.5 Tg N) to the tundra zone with continuous permafrost (628 Tg C and 26 Tg N). The upper 30 cm thermokarst lake sediments of the permafrost-affected WSL store 1250 ± 35 Tg C and 50 ± 1.4 Tg N). The OC accumulation rates in thermokarst lake sediments ranged from 36 to 250 g C m−2 year−1, which is 5 to 10 times higher than C accumulation rates in peatlands of western Siberia. The total OC accumulation in lakes of WSL is 7.8 ± 0.7 Tg C year−1. This is about 24–47% of the C emission from the WSL thermokarst lakes, implying that it represents an important factor in the C budget to consider in order to understand impacts of climate change and permafrost thaw on the C cycle.