The main groups of adjuvants and the prospects of their use for the specific prevention of particularly dangerous and other infectious diseases

The purpose of this review is to analyze scientific data on the adjuvant properties of substances of various origin and chemical nature (adjuvants) published in recent decades and to evaluate the effectiveness of their use in the vaccination against various infections, including particularly dangerous ones. The analysis of the literature data available in PubMed, Web of Science, Scopus, eLibrary databases, indicates that the search for new substances and drugs with the ability to enhance the immune response to antigens that are part of antibacterial and antiviral registered vaccines, as well as experimental preventive drugs, is an important and promising direction. The use of various substances and compounds as adjuvants enhances the immunogenic and protective properties of vaccines, reduces the antigenic load on the human body and causes a tense immune response in individuals with reduced functioning of immune system and in the elderly. When choosing an adjuvant, it is necessary to take into account the direction of its action on the formation of both local and systemic specific immune response, depending on the nature of the pathogen

Mathematical modeling of heat and electromagnetic processes when determining current capacity in cable lines

Ensuring performance and reliability of high-voltage cable lines laid in underground conduits, when designing and operating in limited heat exchange with the environment, it is impossible without a thorough understanding of heat and mass transfer in a duct considering alternating electromagnetic field and induced currents in metal screens realized in cable lines. The study focuses on solution of a collaborative problem of heat and mass transfer and electric and magneto dynamics arising in cable lines laid in underground cable channel under natural convection considering radiation energy and induced electromagnetic fields. The main aim of the study is to develop two-dimensional steady-state mathematical models of heat and mass transfer in natural convection considering electro- and magneto dynamics occurring in cable ducts to determine the rational value ??of current load and to ensure safe operation of the power cables. The methods used in the study: In order to solve the collaborative problem the authors used the theory of heat and mass transfer and electric and magneto dynamics, methods of mathematical modeling. Numerical simulation was carried out using the finite element method in modern engineering packages. The results: The authors solved the joint task of heat and mass transfer and electrodynamics and determined the temperature fields considering the additional heat generation in metal screens of power cables, arising due to the induced currents. The contribution of heat loss due to the induced currents in the cable shield into the overall heat balance of loaded cables was estimated. The paper introduces the recommendations for the largest bandwidth of cable lines depending on the ambient temperature

Numerical simulation of liquid cooling for compact motor

Relevance of the work is caused by the necessity to select the efficient cooling system for compact electric motor under specified conditions of its work. The main aim of the study is to determine by the experiment the efficiency of various existing and proposed designs and patterns for the liquid cooling system of small-sized motor using numerical experiments, to determine the required operating mode by the given conditions of motor heat release; to select experimentally the required refrigerant and geometry of the channel of the cooling jacket to ensure rational parameters of the node in question as a whole. The methods used in the study: experiments based on numerical simulation of complex three-dimensional non-isothermal flow of coolant under constant flow using the finite element method and program complex Ansys. The results: The paper introduces the mathematical model of non-isothermal flow in a three-dimensional formulation. The authors estimated the adequacy of the proposed mathematical model and its numerical implementation, proposed and proved the rational geometry of the motor cooling jacket. The effectiveness of applying different refrigerants was appreciated and technological dependence of cooling system operation efficiency on geometrical and some technological parameters was defined. The paper introduces the graphic visualization of refrigerant flow distribution in the cooling circuit channel. The authors estimated the nature of air flow (laminar / turbulent) in annular and spiral gap, gravity effects on refrigerant held, the possibility of applying coolant from the standpoint of strength capacity of the cooling jacket design. The results obtained can be applied both in developing automatic control systems in industrial equipment and in a local loop responsible for cooling

Numerical simulation of liquid cooling for compact motor

Relevance of the work is caused by the necessity to select the efficient cooling system for compact electric motor under specified conditions of its work. The main aim of the study is to determine by the experiment the efficiency of various existing and proposed designs and patterns for the liquid cooling system of small-sized motor using numerical experiments, to determine the required operating mode by the given conditions of motor heat release; to select experimentally the required refrigerant and geometry of the channel of the cooling jacket to ensure rational parameters of the node in question as a whole. The methods used in the study: experiments based on numerical simulation of complex three-dimensional non-isothermal flow of coolant under constant flow using the finite element method and program complex Ansys. The results: The paper introduces the mathematical model of non-isothermal flow in a three-dimensional formulation. The authors estimated the adequacy of the proposed mathematical model and its numerical implementation, proposed and proved the rational geometry of the motor cooling jacket. The effectiveness of applying different refrigerants was appreciated and technological dependence of cooling system operation efficiency on geometrical and some technological parameters was defined. The paper introduces the graphic visualization of refrigerant flow distribution in the cooling circuit channel. The authors estimated the nature of air flow (laminar / turbulent) in annular and spiral gap, gravity effects on refrigerant held, the possibility of applying coolant from the standpoint of strength capacity of the cooling jacket design. The results obtained can be applied both in developing automatic control systems in industrial equipment and in a local loop responsible for cooling

Mathematical modeling of heat and electromagnetic processes when determining current capacity in cable lines

Ensuring performance and reliability of high-voltage cable lines laid in underground conduits, when designing and operating in limited heat exchange with the environment, it is impossible without a thorough understanding of heat and mass transfer in a duct considering alternating electromagnetic field and induced currents in metal screens realized in cable lines. The study focuses on solution of a collaborative problem of heat and mass transfer and electric and magneto dynamics arising in cable lines laid in underground cable channel under natural convection considering radiation energy and induced electromagnetic fields. The main aim of the study is to develop two-dimensional steady-state mathematical models of heat and mass transfer in natural convection considering electro- and magneto dynamics occurring in cable ducts to determine the rational value ??of current load and to ensure safe operation of the power cables. The methods used in the study: In order to solve the collaborative problem the authors used the theory of heat and mass transfer and electric and magneto dynamics, methods of mathematical modeling. Numerical simulation was carried out using the finite element method in modern engineering packages. The results: The authors solved the joint task of heat and mass transfer and electrodynamics and determined the temperature fields considering the additional heat generation in metal screens of power cables, arising due to the induced currents. The contribution of heat loss due to the induced currents in the cable shield into the overall heat balance of loaded cables was estimated. The paper introduces the recommendations for the largest bandwidth of cable lines depending on the ambient temperature

Numerical simulation application to analyzing heating cable efficiency during mining high viscous oil

Актуальность исследования обуславливается заметным в последние годы увеличением трудноизвлекаемых запасов нефти, связанным с неуклонным истощением легких, маловязких углеродных залежей. Для тяжелых, высоковязких нефтей и природных битумов характерно высокое содержание асфальтенов, смол и парафинов, что приводит к технологическим трудностям и ряду осложнений при извлечении и транспортировке флюида. Для решения проблем, связанных с добычей трудноизвлекаемой нефти, необходимо применять дополнительные технологические операции, направленные на снижение вязкости флюида, что приводит к увеличению себестоимости добываемого сырья. Одним из таких методов может быть прогрев ствола скважины греющим кабелем с целью поддержания необходимой температуры потока и сохранения текучести нефти. Основным недостатком данного метода является высокое энергопотребление, которое можно снизить с помощью методов математического моделирования процессов тепломассопереноса в нефтяной скважине, позволяющих оценить тепловой эффект от работы нагревательного кабеля и определить необходимые технологические характеристики оборудования для беспроблемной эксплуатации скважины. Цель: исследовать влияние нагревательного кабеля на эксплуатацию скважин с высоковязкой нефтью, а также определить необходимые технологические параметры нагрева, при которых нефть сохраняет свою текучесть и обеспечивает нормальную работу глубинно-насосного оборудования. Объект: вертикальный участок нефтяной скважины, где применяется нагревательный кабель для снижения вязкости флюида, расположенной на одном из месторождений республики Южный Судан. Методы: экспериментальное определение реологических и теплофизических свойств нефти на лабораторном оборудовании методами дифференциальной сканирующей калориметрии и реометрии, результаты которого были использованы в качестве исходных данных при математическом моделировании процессов тепломассопереноса в нефтяной скважине с греющим кабелем с целью оценки теплового эффекта от его работы. Численное моделирование дифференциальных уравнений в частных производных осуществлялось с помощью метода конечных объемов в программном комплексе Ansys Fluent. Результаты и выводы. Были получены поля температур, статического давления и скоростей в нефтяной скважине с учетом реологических и теплофизических свойств добываемого сырья при работе нагревательного кабеля с различной мощностью и без него. Показано, что наличие греющего кабеля в скважине благоприятно сказывается на эксплуатационных характеристиках, приводит к снижению вязкости нефти на несколько порядков, уменьшению перепада давления в лифтовых трубах на несколько единиц МПа за счет уменьшения потерь на вязкое трение и росту средней скорости потока. Получено, что эффективность добычи на рассматриваемой скважине можно повысить путем замены нагревательного кабеля на высокотемпературный кабель большей длины, что приведет к увеличению коэффициента подачи и межремонтного периода электроцентробежного насоса за счет поддержания вязкости нефти выше критического значения на всем участке скважины.The relevance of the study is caused by noticeable increase in hard-to-recover oil reserves in recent years, associated with the steady depletion of light, low-viscosity carbon deposits. Heavy, high-viscosity oils and natural bitumens are characterized by high content of asphaltenes, resins and paraffins, which leads to technological difficulties and a number of complications in fluid extraction and transportation. To solve the problems associated with the production of hard-to-recover oil, it is necessary to apply additional technological operations aimed at reducing the viscosity of the fluid, which leads to an increase in the cost of produced raw materials. One of such methods can be heating the wellbore with a heating cable in order to maintain the required temperature of the flow and maintain oil fluidity. The main disadvantage of this method is high energy consumption, which can be reduced using mathematical modeling methods for heat and mass transfer in an oil well, which allow evaluating the thermal effect of the heating cable and determining the required technological characteristics of the equipment for trouble-free operation of the well. The aim of the research is to study the effect of the heating cable on operation of wells with high-viscosity oil, as well as to determine the necessary technological parameters of heating at which oil retains its fluidity and ensures normal operation of downhole pumping equipment. Object: a vertical section of an oil well, where a heating cable is used to reduce the viscosity of the fluid, located in one of the fields in the Republic of South Sudan. Methods: experimental determination of the rheological and thermophysical properties of oil using laboratory equipment, methods of differential scanning calorimetry and rheometry, the results of which were used as input data for mathematical modeling of heat and mass transfer in an oil well with a heating cable in order to assess the thermal effect of its operation. Numerical modeling of partial differential equations was carried out using the finite volume method in the Ansys Fluent software package. Results and conclusions. The fields of temperatures, static pressure and velocities in an oil well were obtained taking into account the rheological and thermophysical properties of the extracted raw materials during heating cable operation with different power and without it. It is shown that the presence of a heating cable in the well has a favorable effect on the performance, leads to decrease in oil viscosity by several orders of magnitude, decrease in the pressure drop in the lift pipes by several MPa due to decrease in viscous friction losses and increase in the average flow rate. It was found that the production efficiency in the well under consideration can be increased by replacing the heating cable with a high-temperature cable of greater length, which will lead to increase in the flow rate and the overhaul period of the electric submersible pump, by maintaining oil viscosity above the critical value throughout the entire section of the well

Модуляція властивостей мезенхімальних стромальних клітин мікрооточенням у 3D культурі

The aim of the research was to compare the shape, viability, metabolic and proliferative activity of mesenchymal stromal cells (MSCs) during cultivation in hydrogels and macroporous scaffolds. Materials and methods. Human adipose tissue MSCs were isolated from lipoaspirates of healthy adult donors after obtaining informed consent. Hydrogels were obtained from platelet-poor human blood plasma and alginate polymer, cross-linked with calcium ions in microspheres. Macroporous scaffolds were prepared from plasma by the cryotropic gelation method. Morphology and viability of cells within carriers were assessed using vital dyes. Metabolic and proliferative activity of MSCs was studied by the Alamar Blue test on the 1st, 3rd and 7th day of 3D culturing. Results. Three-dimensional blood plasma scaffolds had a branched pore structure with a size sufficient for cell proliferation and migration. When plasma proteins were cross-linked with L-cysteine, almost all MSCs were viable, attached to the pore surface, spread and proliferated, filling carrier cavities. In plasma hydrogels, MSCs occupied spaces and acquired a fibroblast-like morphology, maintaining viability. In alginate microspheres, MSCs were uniform distributed throughout the gel volume, kept their spherical shape, but had high viability. The highest metabolic activity of MSCs was observed in macroporous scaffolds, the lowest one in alginate microspheres. During cultivation, the activity of cells in macroporous scaffolds and plasma hydrogels increased significantly, which indirectly indicated the proliferation processes. Conclusions. Properties of MSCs during 3D cultivation significantly depend on the microenvironment: in blood plasma carriers, cells acquire a fibroblast-like morphology and proliferate, while in alginate microspheres, they remain spherical and do not proliferate.Мета – порівняння форми, життєздатності, метаболічної та проліферативної активності мезенхімальних стромальних клітин (МСК) за культивування у складі гідрогелів та макропористих скафолдів. Матеріали та методи. МСК жирової тканини людини виділяли з ліпоаспіратів дорослих здорових донорів після отримання інформованої згоди. Гідрогелі отримували зі збідненої на тромбоцити плазми крові людини та полімеру альгінату, зшитого іонами кальцію у мікросфери. Макропористі скафолди створювали з плазми методом кріотропного гелеутворення. Морфологію та життєздатність клітин у складі носіїв оцінювали, використовуючи вітальні барвники. Метаболічну та проліферативну активність МСК вивчали за допомогою Alamar Blue тесту на 1, 3 і 7-му добу 3D культивування. Результати. Тривимірні скафолди з плазми крові мали розгалужену структуру пор з розміром, достатнім для проліферації та міграції клітин. Коли білки плазми зшивали L-цистеїном, майже всі МСК були життєздатні, прикріплювались до поверхні пор, розпластувались та проліферували, заповнюючи порожнечі носія. У гідрогелях з плазми МСК заповнювали носій та набували фібробластоподібну морфологію, зберігаючи життєздатність. У альгінатних мікросферах МСК були рівномірно розподілені по всьому об’єму гелю, зберігали сферичну форму, але високу життєздатність. Найвища метаболічна активність МСК спостерігалась у макропористих скафолдах, найнижча – в альгінатних мікросферах. За культивування активність клітин у макропористих скафолдах та гідрогелях з плазми суттєво зростала, що опосередковано свідчило про процеси проліферації. Висновки. За 3D культивування властивості МСК суттєво залежать від мікрооточення: у складі носіїв, створених з плазми крові, клітини набувають фібробластоподібну морфологію та проліферують, а в альгінатних мікросфери залишаються сферичними та не проліферуют

Evolution and current development trends of the Russian Federation’s higher education system

The aim of the study is to substantiate evolutionary development stages and current trends in the higher education system in the Russian Federation via general scientific methods of cognition, quantitative and qualitative assessment, methods of comparative and factor analysis, analysis and synthesis, grouping and comparison, the method of logical generalization. As a result, increasing globalization changes the approach to education. The authors came to the conclusion that it is necessary to take into account the impact of external and inter systemic factors on the development of higher education organizations in the Russian Federation.El objetivo del estudio es sustanciar las etapas de desarrollo evolutivo y las tendencias actuales en el sistema de educación superior en la Federación de Rusia a través de métodos científicos generales de cognición, evaluación cuantitativa y cualitativa, métodos de análisis comparativo y factorial, análisis y síntesis, agrupación y comparación, El método de generalización lógica. Como resultado, la creciente globalización cambia el enfoque de la educación. Los autores llegaron a la conclusión de que es necesario tener en cuenta el impacto de los factores externos e intersistémicos en el desarrollo de las organizaciones de educación superior en la Federación de Rusia

Influence of climatic and hydrological factors on structure and composition of peat from northern wetland territories with low anthropogenic impact

Northern wetlands ecosystems play an important role in the hydrological balance of neighboring areas, where they act as chemical barriers against anthropogenic and technogenic contaminations. Studied region is well known for quantity of peat deposits and the volume of peat resources. Peat can be considered as a highly informative marker for assessing change in environmental conditions. The study presents the results of the first investigation of peat samples, collected from representative ecosystems of northern wetland territories with low anthropogenic impact. Component and element composition of various peat types were studied in a relation to hydrologic, climate and sampling conditions. It was found out that organic and ash contents are more dependent on the type of the bog, than geographic location. Climatic factors are more important for the formation of bitumen. The degradation degree in peat increases proportionally to content of humates. High content of biogenic and lithogenic elements was observed in transition-and low-moor peat. The content of trace elements in peat samples do not depend on the type of the peat. The structural properties of peat were studied by the light microscopy, AFM and dynamic light scattering. It was determined that the conformation of studied peat samples is characterized by elements of asymmetry. The observed particles in the solutions exist in dynamic equilibrium with separated globular macromolecules. The size of these nanoparticles is comparable with the size of the particles of other biopolymers of similar nature. Swelling of peat in liquid water was studied. The relationship between structural specificities, origin of peat and its maximum degree of swelling was found. The degree of swelling can be used as structural-sensitive parameter in further research. (C) 2016 Elsevier B.V. All rights reserved