WATER-SOLUBLE POLYMERIC IONIC 5-FLUOROURACIL COMPLEX BASED ON METHACRYLIC ACID COPOLYMERS

Objective: The objective of this work was to obtain a water-soluble 5-fluorouracil (5-FU) polymeric complex on the basis of a methacrylic acid (MAA) copolymer to be used as an injectable chemotherapeutic agent. Methods: A polymeric carrier was synthesized using tert-butyl methacrylate (TBMA) as a monomer, thioglycolic acid, and azobisisobutyronitrile as a radical polymerization initiator. The polymer was converted by acid hydrolysis into a water-soluble copolymer of TBMA and MAA of 20: 80 mass%, respectively. The copolymer of TBMA and MAA was modified with 5-FU. Their formation was proved using IR and UV spectroscopy. The particle size of the 5-FU polymeric complex was estimated by turbidimetry, which is based on measuring the intensity of light transmitted through a disperse system. The release of 5-FU from the obtained ionic complexes by dialysis in vitro was evaluated. Results: Polymeric carriers were obtained with different amounts of 5-FU (5, 15, 25, 50 mol%). A high peak at λ = 266 nm was observed in the UV spectrum of the polymeric carrier (characteristic of 5-FU). The particle size was estimated at 13 nm for the complex with 5 mol% 5-FU and 26.8 n for the complex with 50 mol% 5-FU. The 5-FU release was estimated in two parallel experiments at 37 °C. One utilized a phosphate-citrate buffer with pH 5.0 to model the intracellular space and the other, a phosphate buffer with pH 7.4 to model the intravascular space. Two systems, with 5 and 15 mol% 5-FU, were chosen for testing. In both phosphate buffer and phosphate-citrate buffer, 5-FU was released from the polymeric complex with 5 mol% 5-FU approximately 1.3 times faster than from the complex containing 5 mol% 5-fluorouracil. The kinetics of 5-FU release from the polymeric complex (5 mol% 5-fluorouracil) showed that the 5-FU release was 77.9% in phosphate-citrate buffer and 59.6% in phosphate buffer over 52 h of dialysis. When the 5-FU release kinetics was studied with the polymeric complex containing 15 mol% 5-FU, the 5-FU release was 100.0% in phosphate-citrate buffer and 75.1% in phosphate buffer over 57 h of dialysis. Conclusion: Water-soluble nanoscale complexes of 5-FU with TBMA–MAA copolymers extend application of 5-FU, while its general toxicity might be lower. The complexes are sufficiently stable at pH 7.4 and readily release 5-FU at pH 5.0

The Impact of the Global Financial Crisis on Russia's Cooperation with the Countries of EurAsEC

The article considers the impact of the financial and economic crisis on Russia's cooperation with the EurAsEC countries. Because crises are an integral part of any economic system, a deep analysis should be carried out. We consider the integration at the micro level and prospects of Russia's cooperation with the EurAsEC, the prospects for cooperation between Russia and the EurAsEC countries should be assessed in different ways. Speaking about the cooperation it should be noted that the main weakness of the countries dependent on the prices of natural resources, which are the main export of all countries, including Russia. After all, the raw material orientation determines the country's place in the world. And so the main task here is to develop the production of finished products and the development of knowledge-based industries. Keywords: EurAsEC countries, financial crisis, problems of cooperation, economic globalization. JEL Classifications: F63, F65, G01, H1

Мотивация, заинтересованность, удовлетворенность – движущие силы на занятиях студентов по лыжной подготовке

The study addresses the issue of how to attract the students of non-physical specialties to ski training – a physical, health and socially significant type of activity; there is also an explanation of how such arguments in favor of such activities, increasing interest and motivation. The work contains the survey results, obtained from the second-year students (n=150): the first stage includes motivational factors in ski training – increasing a cold-resistance capacity of body (4.78±0.27), free move following the rules of safe social distance (4.65 ± 0.58), opportunity spend time in the nature, to get aesthetic pleasure (4.44 ± 0.90), opportunity to increase the aerobic capacity of the cardiovascular system through skiing (3.60 ± 1.23), when more than 90 % of the muscles are involved. Further, the main trends in improving the features and technique of ski training, which turned to be the most interesting for students, are identified: skiing at a steady pace by classical style (4.24 ± 1.23) accompanying with the desire to eliminate the technical errors – double-support sliding (143 people = 95.3 %); lack of slide (141 people = 94.0 %); poor sticks work (138 people = 92.0 %). The respondents have shown a real interest in mastering and improving the up-and-down move with different degrees (4.16 ± 0.45). The result of the study lies in defining a simple and easy-to-learn methods for improving the technique of skiing, focusing on the health improvement and dealing with the ski slopesРассмотрена проблема привлечения студентов нефизкультурных специальностей вузов к лыжной подготовке как физкультурно-оздоровительному и социально значимому виду физической нагрузки. Обоснована необходимость поиска аргументов в пользу таких занятий, повышения интереса и усиления мотивации. Приведены результаты социологического исследования среди студентов второго курса (n=150), где на первом этапе были определены факторы мотивации к лыжной подготовке: усиление степени закаливания организма и устойчивость к простудным заболеваниям (4,78±0,27), возможность свободного перемещения с необходимостью соблюдения санитарных норм (4,65±0,58), возможность побывать на природе в лесном массиве, получить эстетическое удовольствие от ее созерцания (4,44±0,90), возможность без ограничения пространства повышать аэробные возможности сердечно-сосудистой системы организма посредством ходьбы на лыжах (3,60±1,23), когда в работу вовлекается более 90 % мышц организма. Далее были определены актуальные направления совершенствования специфических качеств и технических элементов лыжной подготовки, наиболее значимые и интересные для студентов: ходьба на лыжах в равномерном темпе традиционным классическим стилем (4,24±1,23) с желанием устранить грубые ошибки в технике лыжного хода – двухопорное скольжение, отмеченное у 143 чел.– 95,3 %; практически отсутствие проката на скользящей лыже у 141 чел.– 94,0 %; очень слабое отталкивание палками у 138 чел.– 92,0 %. Очевидную заинтересованность студенты проявили в освоении и совершенствовании техники передвижения на спусках и подъемах разной крутизны (4,16±0,45). Итогом исследования стало определение простых и доступных в освоении методов совершенствования техники ходьбы на лыжах оздоровительной направленности, преодоление подъемов и спусков на лыжных трасса

Лыжная подготовка и спортивное ориентирование в блоковой программе учебной дисциплины «Физическая культура и спорт»

Together with the general health care, the training classes in Physical Culture and Sports for non-majors should focus on personal self-fulfillment thorough various forms of physical culture and sports. This has always been in the universities’ academic plans, and the current State Educational Standard (3++), which provides with 400 academic hours for Physical Culture and Sports, is not an exception. These days, the outdoor classes for students are more relevant than ever against the background of the ongoing COVID‑19 and restrictive social and sanitary measures (social distance). This work presents a module-base program and methodological support of teaching within the framework of Physical Culture and Sports discipline, including ski training, orienteering and general physical training. Each training module, which includes 8–13 comprehensive classes, is designed to implement an independent part of educational material following specific natural and climatic conditions. Its usefulness is tested through a pedagogical experiment on the students of Polytechnic School, Siberian Federal UniversityЦель учебных занятий по дисциплине «Физическая культура и спорт» для студентов нефизкультурных специальностей наряду с общим оздоровительным эффектом должна учитывать направленость на личностную самореализацию в разных формах физкультурно-спортивной практики. Это всегда находило отражение в программах обучения вузов, включая и ныне действующий Государственный образовательный стандарт третьего поколения, предусматривающий 400 академических часов для освоения программы учебной дисциплины «Физическая культура и спорт». Сегодня как никогда актуальны занятия для студентов на открытых пространствах на фоне продолжающейся эпидемии и ограничительных мер, вводимых для обеспечения безопасного расстояния между занимающимися по санитарным нормам. В данном исследовании представлено блоковое программно-методическое обеспечение учебного процесса в рамках общего курса дисциплины «Физическая культура и спорт», включающее лыжную подготовку, спортивное ориентирование и общую физическую подготовку. Каждый учебный блок, включающий 8–13 однонаправленных занятий, предназначен для реализации автономной доли учебного материала в соответствии с конкретными природно-климатическими условиями. Его эффективность подтверждена проведенным педагогическим экспериментом в учебном процессе студентов политехнического института СФ

SOFC power plant with circulating fluidized bed gasifier

Coal is used all over the world to meet the energy needs of industry and housing and communal services. The main requirements of coal using are environmental safety and efficiency. Increasing these parameters can be realized with the combination of a gasifier and fuel cells. The paper includes a variant of the thermal scheme of the power plant, which uses coal as a fuel, with its further gasification and conversion into electrical energy in a solid oxide fuel cell (SOFC) stacks. The developed scheme differs from traditional circuits by using a gasifier with an inhibited circulating fluidized bed (ICFB). In addition, the anode-off gases are used in the combustion chamber of the gasifier to maintain endothermic gasification reactions. This technologies combination allows increasing the energy system efficiency. The paper also includes the results of tests of an ICFB gasifier and analyze the available electrical power of the SOFC stacks. Analysis dependence EMF from the produced generator gas composition showed no significant effect on the available power of the electrochemical generator. Developed scheme allow excluding from the process the gas cleaning from tar after gasifier, which allowed to increase the efficiency and reduce the metal capacity of the developed equipment

Solid oxide fuel cells power unit reformer/burner/heat-exchanger module experimental study

The article contains the installation description, experimental procedure, and results for the catalytic partial oxidation reformer/catalyst burner/heat-exchanger module. Mathematical modeling for all major blocks temperatures dependence on the reformer air supply ratio was carried out. In the air supply ratio range under study the model was verified using experimental data. The model was further practically used for the solid oxide fuel cells power unit automatic control modes development. The partial oxidation reforming solid oxide fuel cells power unit characteristics were evaluated

Novel composite Zr/PBI-O-PhT membranes for HT-PEFC applications

Novel composite membranes for high temperature polymer-electrolyte fuel cells (HT-PEFC) based on a poly[oxy-3,3-bis(4′-benzimidazol-2″-ylphenyl)phtalide-5″(6″)-diyl] (PBI-O-PhT) polymer with small amounts of added Zr were prepared. It was shown in a model reaction between zirconium acetylacetonate (Zr(acac)4) and benzimidazole (BI) that Zr-atoms are capable to form chemical bonds with BI. Thus, Zr may be used as a crosslinking agent for PBI membranes. The obtained Zr/PBI-O-PhT composite membranes were examined by means of SAXS, thermomechanical analysis (TMA), and were tested in operating fuel cells by means of stationary voltammetry and impedance spectroscopy. The new membranes showed excellent stability in a 2000-hour fuel cell (FC) durability test. The modification of the PBI-O-PhT films with Zr facilitated an increase of the phosphoric acid (PA) uptake by the membranes, which resulted in an up to 2.5 times increased proton conductivity. The existence of an optimal amount of Zr content in the modified PBI-O-PhT film was shown. Larger amounts of Zr lead to a lower PA doping level and a reduced conductivity due to an excessively high degree of crosslinking

Steroidal Pyrimidines and Dihydrotriazines as Novel Classes of Anticancer Agents against Hormone-Dependent Breast Cancer Cells

Most breast and prostate tumors are hormone-dependent, making it possible to use hormone therapy in patients with these tumors. The design of effective endocrine drugs that block the growth of tumors and have no severe side effects is a challenge. Thereupon, synthetic steroids are promising therapeutic drugs for the treatment of diseases such as hormone-dependent breast and prostate cancers. Here, we describe novel series of steroidal pyrimidines and dihydrotriazines with anticancer activities. A flexible approach to unknown pyrimidine and dihydrotriazine derivatives of steroids with selective control of the heterocyclization pattern is disclosed. A number of 18-nor-5α-androsta-2,13-diene[3,2-d]pyrimidine, androsta-2-ene[3,2-d]pyrimidine, Δ1, 3, 5(10)-estratrieno[16,17-d]pyrimidine, and 17-chloro-16-dihydrotriazine steroids were synthesized by condensations of amidines with β-chlorovinyl aldehydes derived from natural hormones. The synthesized compounds were screened for cytotoxicity against breast cancer cells and showed IC50 values of 7.4 μM and higher. Compounds were tested against prostate cancer cells and exhibited antiproliferative activity with IC50 values of 9.4 μM and higher comparable to that of cisplatin. Lead compound 4a displayed selectivity in ERα-positive breast cancer cells. At 10 μM concentration, this heterosteroid inhibited 50% of the E2-mediated ERα activity and led to partial ERα down-regulation. The ERα reporter assay and immunoblotting were supported by the docking study, which showed the probable binding mode of compound 4a to the estrogen receptor pocket. Thus, heterosteroid 4a proved to be a selective ERα modulator with the highest antiproliferative activity against hormone-dependent breast cancer and can be considered as a candidate for further anticancer drug development. In total, the synthesized heterosteroids may be considered as new promising classes of active anticancer agents

Solubility, Rheology, and Coagulation Kinetics of Poly-(O-Aminophenylene)Naphthoylenimide Solutions

The effect of temperature and storage time at a constant temperature on the stability of poly-(o-aminophenylene)naphthoylenimide solutions in N-methylpyrrolidone has been analyzed using rotational rheometry. A temperature–time window beyond which an irreversible change in the viscoelastic properties of solutions due to cumulative reactions of continuous polymerization and possible intramolecular cyclization has been detected. The influence of polymer concentration and its molecular weight on the rheological properties of solutions determining the choice of methods for their processing into fibers and films has been investigated. The effect of non-solvents (water and ethanol) additives on the rheological properties of solutions and the kinetics of their coagulation has been studied. Dosed addition of non-solvent into the solution promotes a significant increase in the viscoelasticity up to gelation and phase separation. Non-solvent presence in the polymer solutions reduces the activity of the solvent, accelerates the movement of the diffusion front at coagulation, and minimizes the number of macro defects. The combination of parameters under investigation renders it possible for the first time to develop new principles modifying dopes for wet spinning into aqueous or ethanol coagulation bath and finally to obtain a heat- and fire-resistant polynaphthoylenebenzimidazole fibers