bluuebunny/crossref_metadata_2025 huggingface dataset:
The history of entrepreneurship in Sovet Union
Authors: Khadjimuratov A. A. , Mamadaliev N. K.
Published: August 2023

In the article, the views of entrepreneurship in the past of our country, in the era of socialism, were studied. In the study, it was concluded that entrepreneurial activities took place within the “new economic policy” in the form of concession, rental, cooperative, Joint Stock Companies, joint ventures and commandite associations, mainly in the fields of mining and processing industry, agriculture, fisheries and trade. Also, the types of activities of state business structures abroad are shown.
Examining the impact of oil price fluctuations on the development of the transport industry: macroeconomic determinants in GCC countries
Authors: Ushakov Denis , Tarakbayeva Raushan , Ezhak Evgenia , Shatila Khodor
Published: August 2023

The sample nations are particularly relevant since they exhibit a wide range of growth rates, significant financial system features, and stock market development. Not in terms of profits to investors (beyond the scope of our study), but rather in terms of growth compared to the size of these economies and the capital expenditure fund demands of those nations, the research examines the expansion of the equities market and analyzes its international economic impact. To our knowledge, no systematic comparison of Arab capital markets to the many financial systems of the East Asian Pacific region or the seven major Western economies has ever been carried out. In addition, there are no real-world instances of the benefits of stock market output for economic development in Arab nations. While we survey the literature on the capital markets of 11 Arab states, including Bahrain, Saudi Arabia, Tunisia, Egypt, Jordan, Kuwait, Lebanon, Morocco, Oman, and Qatar, our data analysis study zeroes down on only KSA. The research uses an econometric method that covers 10 years (from 2008 to 2018) to analyze the effects of oil prices, currency rates, and stock market performance in Saudi Arabia.
Development of professional foreign language competence within transport industry requirements
Authors: Kobeleva Elena , Stuchinskaya Elena , Dushinina Evgeniya
Published: August 2023

The labour market under current conditions is dynamic and non-homogeneous – it witnesses differentiation in terms of various phenomena and criteria, according to structural changes in the socio-economic environment of society. When considering the labour market requirements for foreign language proficiency, of crucial importance is to take into account the ultimate employers’ needs in the transport industry, the main one being maximum adaptability of graduates-specialists to practical activities in the relevant real sector of the economy. Industry-related educational institutions offer the integrated multi-level system of staff training, retraining and refresher courses conducted under the state regulation in order to meet the state needs. Therefore, to respond to the new challenges, which the transport industry is facing, the educational process continuity requires expansion of professional competencies into supplementary fields of knowledge, taking into account the international labour market condition. Among these, a high level of foreign language proficiency should be noted, which is a significant competitive advantage for a transport university graduate. The authors of the research formulated the industry-related requirements for the level of foreign language proficiency, determined the relevance of improving the quality of foreign language training of students at a transport university, and proposed the methodology guidelines for the use of mnemonics in the process of forming the professional foreign language competence of future economists.
“Green” loan – a “green” financing instrument
Authors: Gulzhan Alina , Kerimkulova Dinara , Yessymkhanova Zeinegul , Orazbayeva Aigul , Alibekova Aigul
Published: August 2023

To achieve the goals of sustainable development and the transition to the “green” economy requires not only substantial financial resources but also the transformation of traditional financing. In order to finance projects and productions aimed at improving the environmental and social components of human life, innovative financing instruments such as “green” loans are required. Today, in the context of the world’s global desire for sustainable development, the development of a “green” economy and “green” financing instruments is relevant. The market of “green” loans is relatively new both for the global financial market in general and for the domestic market in particular. In this regard, the issue of studying the available green loans on the domestic and global market is relevant. This paper presents a study of an environmental project loan, encompassing an analysis of existing research on the chosen topic, an examination of the regulatory principles of “green” lending. The authors proposed a classification of the types of “green” loans, as well as identified their advantages and disadvantages.
The formation of the digital economy and its conceptual model
Authors: Otakuzieva Zuhra
Published: August 2023

This article presents various scientific approaches to digital economy, separate groups of digital economy theories and conditional separation of authors according to them, its three main stages in the formation of conceptual integrity of digital economy, the system of relations of its institutional components in digital economy development, its mechanisms in digital economy The main components of the economy: e-government; electronic commerce; opinions on electronic employment are stated.
Improvement of indicators of socio-economic development of the regions of Kazakhstan
Authors: Turekulova Dametken , Beisengaliyev Berik , Turekulova Assiya , Saimagambetova Gaukhar
Published: August 2023

This article presents a comparative analysis of the socio-economic development of the regions of the Republic of Kazakhstan for ten years from 2011 to 2020. The analysis was carried out on the basis of statistical data of the main macroeconomic indicators such as: Gross regional product, the share of the region in the GRP structure, the growth rate of the region’s economy, GRP per capita. On the basis of the analysis carried out, imbalances in regional economic development were identified, in particular, donor regions that make the greatest contribution to the structure of the country’s GRP and recipient regions that make the least contribution to the country’s economy were identified. The regions with the fastest growing GRP growth rates over the last decade and regions showing low rates of economic development were also identified. In addition, the main macroeconomic characteristic of the region is the GRP per capita indicator, reflecting the level of well-being of the region’s population. As a result of the analysis, the regions with the highest and lowest levels of GRP per capita were identified. Thus, on the basis of a comparative analysis of the regions over the past 10 years, imbalances in regional development, existing economic problems reflected in the different dynamics of the main macroeconomic indicators have been identified. Based on the analysis, recommendations were proposed for further improvement of the state policy of regulating the socio-economic development of regions in the Republic of Kazakhstan.
The role of green marketing in regional sustainability
Authors: Nikonova Natalya , Mottaeva Angela
Published: August 2023

The article raises questions of analysis of the mutual dependence of regional social, economic and environmental situation. In total, their indicators form the concept of regional sustainable development. The authors carried out a comparative analysis of the regions of the Volga Federal District, identified the leading regions (Tatarstan and Bashkortostan) and outsider regions (Saratov region). The study showed a direct relationship between the studied indicators, which means that the growth of any of them will positively affect the state of the others. Green marketing in the context of regional development is designed to increase the attractiveness of the region from an environmental standpoint, which should lead to an increase in socio-economic indicators.
Evolution of the entrepreneurship in Uzbekistan
Authors: Hadzhimuratov A.A.
Published: August 2023

This article discusses the evolution of entrepreneurship in Uzbekistan based on historical sources. In this regard, a number of factors that played a role in the emergence and development of entrepreneurial activity on the territory of Uzbekistan were studied. The scientific basis of the article is that the author divided the evolutionary development of entrepreneurship into five stages. Also, each stage of entrepreneurial activity in the history of our country is studied separately, their specific historical and economic role is indicated. Also, each stage of entrepreneurial activity in the history of our country is studied separately, their specific historical and economic role is indicated. It also explains the importance of these evolutionary stages of entrepreneurship in the process of creating a national model of a market economy in Uzbekistan at the present time.
Elements of the spatial scenario of historic housing as an invariant code of innovative typology “house-yard”
Authors: Malakhov Sergey , Repina Evgenia , Busel Yuliya
Published: August 2023

The morphological, structural and content elements that form an invariant model of innovative multifunctional typology “house-yard” are considered. The continuity of this model in relation to the historical urban neighborhood development as a prototype is established. The possibility of creating a new typology, focused on modern methods of construction and actualization of the characteristics of a sustainable urban environment is substantiated
Urban environment harmonious development in the pedestrian crossings’ organization process in Yerevan
Authors: Karamyan Anahit , Sargsyan Emilia , Babayan Lilit
Published: August 2023

From the beginning of the 20th century to the present day, the intensively developing transport system in the world causes new problems in the organization of the architectural environment. The invasion of vehicles into the urban environment brought about the need for new approaches due to the modern architectural organization of the spatial environment with the requirement to organize conditions that meet the comfort, safety and modern needs of human life activity. The subject of the study is the new problems generated by the rapidly developing transport system in the issue of comfortable life of the pedestrians in the architectural environment. Vehicles, especially in urban settlements, occupying huge territories, cause serious difficulties in the movement of pedestrians. As a result, regulated ground and underground crossings have become the main route of interchange in the city of Yerevan, which today need new approaches. The purpose of the article is to outline new approaches to improving the spatial environment aimed at improving the pedestrian-transportation relationship.
Criminal-legal guarantees for participants of share construction: problems and prospects
Authors: Ulezko Sergey , Ulezko Ivan , Shabliy Julia , Elmira Hajiyeva , Zahid Valiyev
Published: August 2023

The aim of the article is to investigate the optimal criminal law guarantees for citizens investing in the construction of apartment buildings and other real estate. The goal set by the authors is achieved by analyzing the current criminal legislation of Azerbaijan and Russia. During the study the authors used a systemic and structural-functional methods of scientific knowledge, the method of interpretation of legal norms and logical method. Various criminal law instruments providing guarantees to investors in the construction of apartment buildings were considered. The authors concluded on the need to introduce criminal liability for the involvement of funds of citizens in violation of the legislation on participation in shared construction of apartment buildings and (or) other real estate. In formulating the disposition of the norm necessary to consider the shortcomings of the Russian legislation and law enforcement practice relating to this issue.
The ambivalence of modern technology at the stage of technogenic civilization
Authors: Grebennikova T. L. , Burova A. Yu.
Published: August 2023

The article focuses on defining the essence of modern technology, its ambivalent characteristic and determining its significance in the structure of the technogenic civilisation. The aim is to determine philosophical, methodological and scientific direction of research into the possibilities of practical application of the systems approach in civil aviation to ensure flight safety. It is revealed that the dual importance of technology includes making sense of it, using technology in its essence and finding ways out of the problems created by technology and technological civilisation. The results of this study have shown and confirmed that a systematic approach can be used to improve the quality of aircraft.
Analysis of urban communal water supply
Authors: Kochkarova Ch. , Abdurakhmanov A. , Jumanova M. , Tursunov H. , Jalilov A.
Published: August 2023

Currently, the incomplete provision of wastewater treatment facilities for municipal and industrial industries, their proximity to canals, collectors, river banks and other water bodies, leads to significant pollution of water resources. On the basis of the Action Strategy for the five priority areas of development of the Republic of Uzbekistan for 2017-2021, paragraph 4.3 reads: defined as strategic tasks [1; 2]. It is important to reduce the impact of municipal wastewater on open water bodies, to carry out scientific research on environmental protection. At the same time, the use of water and aquatic plants in the biological treatment of water is about 80% effective in the treatment of organic contaminants in wastewater, 40% in the physicochemical method and about 30% in the mechanical method [3].
Assessment of innovation activity of Kazakhstan regions
Authors: Chereyeva Bakhytgul , Niyazov Mussa , Yesturlieva Aigul , Bermukhamedova Galiya
Published: August 2023

In the age of technology, the role of innovation is increasing, the development of which depends on financial investments, which indicates a close relationship between investment and innovation. In this regard, the authors conducted a correlation and regression analysis, which helped to determine the factors influencing innovation activity on the example of the regions of Kazakhstan. As a result of modeling, a high degree of influence on innovation activity was determined by factors such as investment in innovation, as well as the number of created and used innovation facilities. The regression model was tested on the indicators of Almaty, which made it possible to make predictions.
Approach to environmental issues
Authors: Muhamediyeva D. T.
Published: August 2023

Z-numbers have been used to address environmental monitoring issues. A computational experiment based on a combination of odd and even numbers was also performed and their comparative analysis was considered. Results of experimental research using Z-assessment in obscure conclusion systems have been applied, and this approach has been used to address environmental monitoring issues in the case of a poorly formed process.
The impact of women’s labor resources on economic growth in Uzbekistan
Authors: Khidirov Nodir , Mamadjonova Sarvinoz
Published: August 2023

One of the main economic and social wealth of Uzbekistan is its people. Although policymaker pay the special attention at the gender equality in almost every aspect of our lives, we still have gender bias in our labor market. The current study empirically investigated the relationship between female labor force participation and economic prosperity of the country. The paper implemented Granger casualty test to define which variable causes to change another variable amongst the gathered secondary data, after it employed Last Squares method to define the long term relationship amongst variables such as GDP, female labor force participation rates (FLFPR), fertility rates, female unemployment rates, female higher educational attainment and women in business and law index. The study showed that GDP influences the tribulations in rates of female labor force participation, and not on the contrary. Meanwhile, OLS regression gave a negative output of the correlations amongst GDP, Female Unemployment Rate, and Female in Business and Law Index regarding to the FLFPR. The significance of Women in Business and Law index is insignificant. In contrast the long term positive relationship is defined among fertility rate and higher education attainment with FLFPR. But in case of fertility rates the variable is insignificant.
Method for applying vehicle driving cycles to assess the durability of electromechanical transmissions of trucks
Authors: Grinin Valeriy , Shkarupelov Evgeniy , Muravev Aleksandr , Kartashov Aleksandr , Nazarenko Sergey , Klimov Aleksandr
Published: August 2023

The article discusses the relevance of the problem of calculating the elements of electromechanical transmissions of trucks for strength and durability. The main methods used for the formation of load conditions on electromechanical transmissions of trucks are given. The driving cycles of trucks used to obtain loads when calculating the durability of the elements of electromechanical transmissions are given. The universal driving cycles of vehicles obtained on the basis of the collection of statistical data on the movement of trucks are considered. A simulation model of the movement of a truck used to determine the loads on the electromechanical transmission while overcoming driving cycles of trucks is presented. The durability of the gears of the electromechanical transmission of a truck is analyzed on the basis of load cyclograms obtained during simulation modeling of movement. Numerical results of the safety factors of one of the gear stages are obtained. Conclusions are drawn about the optimality of the use of existing driving cycles of trucks in strength calculations. Conclusions are worded about the need to synthesize driving cycles of trucks based on the collection of statistical data on the movement of truck vehicles on the territory of the region under consideration.
Analysis of small modular reactor technologies and socio-economic aspects of their application in the Russian Arctic in the era of digital transformation
Authors: Merkulov Viktor , Didenko Nikolay , Skripnuk Djamilia , Kulik Sergey
Published: August 2023

Small modular reactor technologies and social, economic, and technological aspects of their application in the Russian Arctic are considered in the article. An overview of the key factors influencing an implementation of small modular reactor plants in remote regions with a decentralized power grid is presented. The main directions of small modular reactor design activities of the key Russian centers of atomic research and development are given. An overview of current Russian small modular reactor technologies including pressurized water reactors, boiling water reactors, reactors installed on floating nuclear power plants, high-temperature gas-cooled reactors, and liquid metal cooled reactor is conducted. Economic, social, ecological, and digital aspects of applications of small modular reactor in the Russian Arctic are considered. A detailed survey of areas of small modular reactor application including extractive, processing, industrial energy-intensive facilities, and power and heat supply of cities is also given. The importance of digital twins of small modular as an essential element in the development and maintenance of complex engineering products and industrial facilities throughout the entire life cycle is discussed in the article. Conclusions about key advantages and prospects of an application of small modular reactors in the Russian Arctic are made.
Longitudinal wave propagation in an extended cylindrical body with external Coulomb friction
Authors: Khusanov Bakhtiyar , Rikhsieva Barno , Salikhova Zulfiya
Published: August 2023

The propagation of elastic longitudinal waves in an extended cylindrical body located inside an unstrained body and interacting according to the Coulomb law is considered in the article. The problem is studied in a two-dimensional statement; therefore, the friction force (i.e., the interaction conditions) is included in the system of equations as a boundary condition. The Coulomb friction force arises due to the deformation of a cylindrical body. The reliability of numerical calculations is substantiated by solving test cases and comparing the calculations with experimental results. The numerical results obtained are presented in the form of graphs and analyzed. It is shown that the parameters (stresses and strains) of waves propagating in an elastic cylindrical body with external Coulomb dry friction decay with distance. The mechanism for reducing the stress-strain state and wave parameters is explained by the consumption of elastic energy to overcome the friction force that occurs on the contact surface. The results of the two-dimensional problem are also compared with the results of a similar problem in the one-dimensional theory, where the friction force enters directly into the equations of motion. The deviations of the results of the one-dimensional theory are up to 8-15% depending on the accepted values of the friction coefficient, i.e. the violation of the plane section hypothesis taken in one-dimensional calculations amounts to 15%. With a decrease in the radius of a cylindrical body, these deviations are reduced.
The rotational motion simulation of AIST small spacecraft prototype based on current values and on a hardware-software stand
Authors: Khnyryova Ekaterina
Published: August 2023

Improving the quality and volume of drilling is the main condition for advancing the growth of reserves of raw materials of the national economy and industry. Rock-breaking tools are the main and busiest part of drilling equipment. Most of the operational productivity of drilling equipment depends on the operation of a rock-breaking tool, the improvement of the operational performance of which will reduce the cost of drilling wells and significantly increase drilling efficiency. The issues related to increasing the operational productivity of drilling equipment based on improving the design of rock-breaking tools have not been fully resolved, and their solution is now becoming important. This article presents the results of research devoted to the problems of reducing the efficiency of rock-crushing tools that arose as a result of high temperature at the bottom of the well when cleaning the bottom of the well by blowing air, as well as the sludge regime that occurs during drilling with cleaning with washing liquids prepared on the basis of water. Special attention is paid to improving the efficiency of drilling equipment by creating and implementing a rock-breaking tool design with high performance indicators.
Information characteristics of an orbital side-scan synthetic aperture radar
Authors: Chernoyarov Oleg , Ivanov Vladimir , Chernoiarova Elena , Litvinenko Yuliya
Published: August 2023

Ratios are given for estimating the amount of information in the channels of sensing and data transmission of the orbital synthetic aperture radars (SAR) based on information-theoretic and statistical methods. They are presented in terms of the indicators characterizing the amount of information received about the state of the object of observation. It is shown that the sensing channel should use significantly redundant information in relation to the final result of radar observation. On the example of the SAR of the “Venera-15” and “Venera-16” spacecrafts, the specific conditions of an orbital radar imaging are illustrated, and its informational characteristics are given for both methods of transmitting observation data. The qualitative consideration carried out in the paper makes it possible to estimate the potentially achievable reduction in the amount of information in the data transmission channel when using on-board SAR signal processing under specific radar imaging conditions.
Improving the efficiency of the cutting tool based on its modification
Authors: Romanov P.
Published: August 2023

Currently, carbide cutting tools are mainly used for processing blanks of machine parts. Increasing the working life of carbide plates is one of the urgent tasks in mechanical engineering. The paper proposes to increase the working life due to the complex modification of the working surfaces of the carbide tool. Modification of the tool surface is proposed to be carried out on the basis of electron beam alloying with an alloy based on niobium and hafnium, followed by the application of a wear-resistant coating of titanium aluminitride.
Study of the influence of the performance of a raw cotton cleaner on changes in the rotation speed of the peg drum
Authors: Bobomatov Abdugani , Akbarov Alisher
Published: August 2023

The optical sensors used have their own internal resistance, the extinction of which is leads to the fact that the sensor gives a certain signal. When a beam of light hits the optical sensor, the internal the resistance of the sensor decreases. For the reliability of the results obtained, each experiment was carried out in four repetitions. All experiments were carried out under the same conditions at a constant set rotation speed peg drum.
Study of ACS of rotor rotation frequency and gas temperature with accurate regulators in the control loop of a gas turbine engine
Authors: Bogdanov A.V. , Larkina A.A.
Published: August 2023

This article discusses the automatic control system for parameters (rotor speed and gas temperature) of a gas turbine engine based on clear logic controllers. It is proposed to use clear logical controllers, consisting of a comparing device, a fuzzifier, an inference block with a system of production rules and with given membership functions of clear terms of variables, and a defuzzifier. Precise logical controllers, using the membership functions of precise terms, in the control loops of the object’s influence stably maintain the overshoot time.
Analysis of skelp deformation zones for the down trajectory of electrically welded pipes forming
Authors: Samusev S.V. , Sidorova T. Y. , Nguyen V.T.
Published: August 2023

Deformation zones along the down trajectories of skelps forming using the forming mill TESA10-50 (Pipe Electrical Welding Unit) were considered. For pipes with 50×1.5 mm diameter, strained conditions for forming zones were identified for different options of down trajectories length with the as-formed skelp initial position upward gradient within the range of H = 0÷50 mm. It was determined that increase in the down trajectory length contributed to the decrease in longitudinal strain values, however, it could not provide for forming within the allowable values along the entire forming zone of the mill. Reduction in the skelp curvature by 8÷13 % resulted in the longitudinal strains decrease at the skelp edge along the entire forming zone length.
The impact of fillers on the biodegradation of plasticized PVC-materials exposed to soil microorganisms
Authors: Perushkina Elena , Sadykova Dilyara , Gotlib Elena , Sokolova Alla
Published: August 2023

Due to the growing use of polymer materials, in particular in construction sphere, the issue of their recycling at the end of their service life is particularly relevant. Being the base for flooring, plasticized PVC-compositions, are utilized by soil microbial flora, as the plasticizer EDOS has a positive effect on the microbiocenosis of the soil. It was shown that for aqueous extracts of samples of PVC-compositions, there is no toxicity for two test objects - infusoria Paramecium caudatum and crustacean Daphnia magna. Filling plasticized PVC-materials with natural wollastonite Miwoll 10-97 inhibits the processes of soil respiration, and rice husk ash and synthetic wollastonite on its base, contribute to its preservation. At the same time, the use of these fillers reduces the degree of utilization of plasticized PVC-compositions by soil microbial flora, since the plasticizer EDOS is adsorbed on their surface and becomes less accessible for soil microorganisms. This was proved by infrared spectroscopy and occurs due to the formation of hydrogen bonds between EDOS and rice husk ash.
Vibration based damage detection of bridge structures
Authors: Shatilov Yu.Yu. , Lyapin A.A. , Cherpakov A.V. , Glushko S.G.
Published: August 2023

The task of identifying damage to the load-bearing beams of large-span bridge structures using vibration diagnostic methods has been implemented, taking into account experimental uncertainties associated with natural phenomena and technological processes. The methodology for localizing damage is based on the analysis of dynamic characteristics of the structure, such as natural frequencies and modes of vibration. The study presents research on a finite element model of a bridge structure using a method for determining a damage indicator based on normalizing the values of vibration modes with respect to the values of vibration area.
Modelling the dynamic force of bridge crossings
Authors: Loktev Alexey , Korolev Vadim , Shishkina Irina
Published: August 2023

Viscoelastic elements of Kelvin-Feugt type are supposed to be used for modelling dynamic influences from the transport side and dynamic behaviour of separate elements and the whole structure as a whole. Periodic monitoring of bridge crossings using the considered approaches will make it possible to detect the presence of defects in the span itself, associated with the formation of cracks, spalling, because in the presence of such defects the estimated frequencies change.
Mechanisms for restoring the solvency of Russian agricultural debtors
Authors: Skvortsova Tatyana , Pratsko Gennady , Marchenko Ekaterina
Published: August 2023

The purpose of this article is to analyse the mechanisms to restore the solvency of Russian agricultural organisations. The achievement of the goal set by the authors is carried out as a result of the study of socioeconomic factors affecting the financial stability of agricultural organisations, as well as consideration of the provisions of regulations that provide mechanisms for financial recovery of agricultural organisations both outside the bankruptcy procedure and within the bankruptcy procedure. In carrying out the study, the authors used systemic and structural and functional methods of scientific knowledge, the method of interpretation of legal norms, and the logical method. As a result of the study of various factors that affect the financial stability of agricultural organisations, the authors came to the conclusion that they should be taken into account in the formation of a system of measures aimed at restoring the solvency of agricultural organisations and the establishment of regulatory and legal regulation of rehabilitation procedures in respect of such organisations. According to the authors, the proposals for improving the mechanisms of restoring the solvency and sustainability of agricultural organizations will ensure the progressive development of the agro-industrial sector of the Russian economy.
Organizing the international marketing environment and relationships
Authors: Berdimurodov U.S. , Abdurokhmonov Sh.X. , Umirov N.T. , Khudaikulov F.R.
Published: August 2023

In the article, the international marketing environment and its study, the reasons for the organization of international marketing services, the political and legal environment, the main purpose of entering the foreign market, making a decision to enter the international consumer market, export of goods, cooperative entrepreneurship, the organization of international marketing relations, political- legal environment and the main goal of entering the foreign market, the development of marketing services, the conclusions on the sustainable development of socio-economic relations between the countries are given.
Research of the oxidation process of N-Butane waste of “Sho’rtangazkimyo” LLC in heterogeneous catalysts
Authors: Fayzullaev Normurot , Kholliyev Shamsiddin
Published: August 2023

In the article, n-butane, which is a waste of “Shortangazkimyo” LLC, has a porosity of 33% obtained by reaction with potassium permanganate solution in aqueous solutions at temperatures above 100 ℃ and pressures above 1 atmosphere. In the presence of a catalyst containing xTiO2•(1-x)SiO2 (x=0.0001-0.04), the influence of concentration, the ratio of n-butane to potassium permanganate, solvent, temperature, pH and other factors on the rate of oxidation reaction was studied. The best solvent for oxidation of butane with potassium permanganate solution is ethyl alcohol, it provides maximum selectivity for the formation of butanone-2 and is stable under oxidative conditions. Increasing the ratio from 2:1 to 6:1 increases the butanone-2 yield from 28 to 44% and the selectivity from 50.7% to 63%. It was found that the productivity of butanone-2 (17%) and selectivity (20%) decreased in the ratio of n-butane, a waste product of “Shortangazkimyo” LLC, to potassium permanganate solution=1:2, which is related to the formation of a two-phase system. As the temperature increases from 50 ℃ to 90 ℃, the yield of butanone-2 increases from 13.4 % to 30.5 % and the conversion rate of potassium permanganate solution increases from 37 to 97 %. The dependence of the selectivity of potassium permanganate solution on butanone-2 is unusual with a maximum of 70 ℃ (54.15%). Thus, the conducted research allows us to conclude that the optimal conditions for the synthesis of butanone-2 are: temperature - 70 ℃; Catalyst concentration of xTiO2•(1-x)SiO2 (x=0.0001-0.04) with 33% porosity obtained by reaction in aqueous solutions at temperatures above 100 ℃ and pressures above 1 atmosphere is 38.99 g/l; The molar ratio of nbutane, which is a waste of "Sho’rtangazkimyo" LLC: potassium permanganate solution - 3:1; pH=7.
The effect of copper and iridium input atoms on the recombination properties of silicon
Authors: Mirzarayimov Jahongir
Published: August 2023

In monocrystalline silicon, which is easily condensed with copper and iridium, the recombination time is more stable compared to conventional samples. If the concentration of recombination centers in silicon is less than the concentration of adhesion levels, the residence time of non-basic charge carriers increases, and its values are determined by the concentration of adhesion levels. Compared to conventional silicon samples that were legalized with copper and iridium, a large concentration of copper and iridium was observed in neutron-legalized samples. Сoncentration maxima are observed in the DLTS spectra after thermal diffusion of samples of n-Si, n-Si at 1150 oC. This was followed by the study of the structure, size and distribution of silicon mixing defects, which was legitimized by copper and iridium, using ATM.
Inflammatory Mediated Chronic Anemia in Patients Supported with a Mechanical Circulatory Assist Device
Authors: Pierce Christopher N. , Larson Douglas F. , Arabia Francisco A. , Copeland Jack G.
Published: August 2023

It is widely accepted and clinically anticipated that the patient implanted with a mechanical circulatory assist device (MCAD) will develop a state of chronic anemia that will last throughout the duration of MCAD support. Large-scale hemolysis mediated by the high sheer stress transmitted to the erythrocytes (RBCs) from the mechanical action of most MCAD systems is the accustomed mechanism responsible for this anemic status. MCAD patients exhibiting chronic anemia require frequent blood transfusions placing the patients at a high infectious risk to maintain an acceptable hematocrit. It is also acknowledged that the biomaterial interaction of the MCAD with the immune system precipitates a chronic inflammatory state in this patient population. Taken together, we hypothesize that inflammatory mediation of the erythropoiesis pathway at multiple sites—limiting the replacement of lysed RBCs—dictates the extent of chronic anemia in MCAD patients more than mechanical trauma to the blood. Hematological parameters were retrospectively analyzed for 78 patients implanted with a mechanical circulatory assist device for greater than 30 days at the University of Arizona Health Sciences Center between the years 1996 to 2002. Analysis demonstrates that the rate of hemolysis slows after MCAD implantation, marked by a progressively decreasing plasma hemoglobin concentration. In addition, the absolute reticulocyte count, a marker of juvenile RBC production, increases and remains above maximum normal values after MCAD implantation. Furthermore, the mean cell hemoglobin concentration indicates sufficient substrate for RBC development and maturation. However, hematocrit, a conventional marker of anemia, drops and remains below minimum normal value throughout the measured time period. A state of anemia in the MCAD supported patient results initially from the effect of hemolysis associated with the mechanical action of the MCAD, then chronically persists as the result of another undetermined mechanism. Given the state of chronic inflammation in the patient population, immunological activation most likely limits the full production of RBCs to their mature state.
North American Neonatal Extracorporeal Membrane Oxygenation (ECMO) Devices: 2002 Survey Results
Authors: Lawson D. Scott , Walczak Rich , Lawson Andrea F. , Shearer Ian R. , Ing Richard , Schulman Scott , Kern Frank , Jaggers James
Published: August 2023

In mid 2002, surveys of active extracorporeal membrane oxygenation (ECMO) centers in the United States and Canada were conducted via E-mail regarding neonatal equipment and personnel. Seventy-four out of 99 (75%) North American ECMO centers listed in the Extracorporeal Life Support Organization (ELSO) directory responded to the survey. Of the responding centers, 95% use roller pumps, and the remaining 5% use centrifugal pumps. Silicone membrane oxygenators were used by 97% of the respondents, while 3% used hollow fiber oxygenators. Of the silicone membrane oxygenator users, 82% used the Medtronic ECMOtherm heat exchanger, 15% used a Gish heat exchanger, and 3% used the Dideco D720 heat exchanger. Sixty-one percent of the responding centers used some form of in-line blood gas monitoring. Five percent of the centers used a bubble trap in the arterial line, and 12% used an arterial line filter. A bladder was used by 92% of the centers, and 29% used a mechanical bladder box for servo regulation, the remaining 71% used pressure servo regulation. An air bubble detector was used by 65% of the responding centers, although 81% had the device available. Heparin coating was used by 5% of the centers on all their neonatal ECMO patients. The average low range ACT was 183 seconds, and the average high range ACT was 216 seconds. At 49% of the responding centers, perfusionists were involved with the ECMO program, registered nurses were involved at 84% of the centers, and respiratory therapists were involved at 61% of the centers, perfusion assistants were involved at one center (1%), and biomedical engineers were involved at one of the centers. When compared to a 1990 survey, a shift away from using bladder boxes and toward using air bubble detectors is apparent. But other than those two shifts, ECMO is done in much the same manner as it was done 12 years ago.
Plateletworks™ Platelet Function Test Compared to the Thromboelastograph™ for Prediction of Postoperative Outcomes
Authors: Ostrowsky Jacob , Foes Jennifer , Warchol Mark , Tsarovsky Gary , Blay Jessica
Published: August 2023

Approximately 3.5 million units of platelets are transfused in the United States each year to patients undergoing open-heart surgery with cardiopulmonary bypass (CPB). CPB is a known contributor to platelet loss and platelet dysfunction leading to disruption of hemostasis. Impaired hemostasis results in excess bleeding in 5–25% of all patients undergoing CPB. For this reason, it may be beneficial to measure platelet number and function in these patients. The purpose of this study was to compare the Plateletworks™ platelet function analyzer to the thromboelastograph (TEG) in predicting postoperatiave hemostatic outcomes as measured by blood product use and chest tube (CT) drainage. This study consisted of 35 adult patients undergoing cardiac surgery with cardiopulmonary bypass at Rush-Presbyterian-Saint Luke’s Medical Center (RPSLMC). The Plateletworks™ and TEG tests were performed preoperatively, after protamine was given, and 24 hours postoperatively on all patients. Plateletworks™ demonstrated a statistically significant change in platelet function as shown by the adenosine diphosphate (ADP) reagent tube from the preoperative period to the removal of the aortic cross clamp (p = .011). The TEG did not demonstrate a significant change in the k-time and maximum amplitude (MA), but did show a significant change in the alpha-angle from the pre-operative to postoperatiave sample (p = .035). A correlation was found between Plateletworks™ collagen reagent tubes preoperatively and CT drainage (p = .048, r −0.324). No statistical correlation was established between TEG parameters and CT drainage at any time interval. TEG preoperative MA showed a correlation to receipt of blood products (p = .016). When comparing the Plateletworks™ to the TEG in this study, the Plateletworks™ system was a more useful predictor of blood product use and chest tube drainage.
Argatroban Usage For Anticoagulation for ECMO on a Post-Cardiac Patient with Heparin-Induced Thrombocytopenia
Authors: Mejak Brian , Giacomuzzi Carmen , Heller Eileen , You Xiaomang , Ungerleider Ross , Shen Irving , Boshkov Lynn
Published: August 2023

We report a post-Norwood Stage I patient requiring ECMO support using Argatroban as an anticoagulant following diagnosis of heparin-induced thrombocytopenia (HIT). A 2.6 kg female was born with hypoplastic left heart syndrome and underwent a Norwood Stage I operation on day 4 of life. The patient weaned off cardiopulmonary bypass with no complications and was routinely placed on a ventricular assist device (VAD) for 3 days. Heparin was infused at a rate of 16–32 IU/kg/h to maintain an ACT of 160–180 seconds. Two days after VAD termination, the patient was placed on continuous veno– veno hemofiltration (CVVH). Shortly after CVVH, the patient was diagnosed with HIT and placed on an Argatroban infusion. Five days later, a VAD and subsequent ECMO was used because of decreasing left ventricular function, gross body edema, and poor renal function. This case report summarizes the use of Argatroban during VAD and ECMO support for a patient diagnosed with HIT.
Rationale of Platelet Gel to Augment Adaptive Remodeling of the Injured Heart
Authors: Mogan Christopher , Larson Douglas F.
Published: August 2023

Cardiac pathologic events including; myocardial infarction, viral infection and hypertrophy, and aging, may trigger maladaptive remodeling of the myocardium. Maladaptive remodeling results in diastolic and systolic dysfunction, myocyte loss, and malformation of the extracellular matrix. It is proposed that platelet gel applied to the site of myocardial injury may provide the proper cytokines, growth factors, and chemokines to promote adaptive remodeling. The hypothesis is that platelet gel concentrates may provide a temporary and local hyperphysiologic concentration of platelet secretory factors that may initiate adaptive myocardial healing. Autologous platelet gel can be derived from concentrated platelets activated and induced to secrete cytokines, growth factors, and chemokines with an array of stimulating agents. This report discusses selected platelet secretory factors, including; IL-1β, TGF-β, TGF-α, FGF, EGF, PDGF, and IGF, which support the concept that platelet concentrates can mediate cardiac wound healing. In conclusion, application of platelet gel to areas of cardiac injury may offer a therapeutic means to stimulate myocyte regeneration, angiogenesis, and restoration of a normal extracellular matrix composition.
An Ultrafiltration Technique for Directly Reinfusing Residual Cardiopulmonary Bypass Blood
Authors: Smigla Greg R. , Lawson D. Scott , Shearer Ian R. , Jaggers James , Milano Carmelo , Welsby Ian
Published: August 2023

Given the shortages of banked blood, the risks of transfusion reactions, disease transmissions, and transfusion errors, we perfusionists must find ways to avoid blood transfusions. At the end of any given bypass run, there is residual blood left in the bypass circuit, the perfusionist must get this blood back to the patient. Most commonly either a cell saver or a hemoconcentrator (HC) has been used, in some fashion, to reinfuse residual circuit blood. The ideal method should: 1) be simple; 2) raise the hematocrit (HCT); 3) allow for changes in the patient’s volume status; and 4) not compromise the integrity of the cardiopulmonary bypass (CPB) circuit allowing for rapid re-institution of CPB. We describe a technique in which residual CPB circuit blood is pumped through an HC directly to the patient via a 3/16-inch diameter line into a 16-gauge intravenous needle positioned in a peripheral or central vein. This allows the perfusionist to give back concentrated blood that is protein-rich while maintaining the above criteria.
Database Review of Possible Factors Influencing Point-of-Care Platelet Gel Manufacture
Authors: Waters Jonathan H. , Roberts K.C.
Published: August 2023

The application of autologous platelet gel (APG) to surgical wounds has been advocated during the last 10 years to speed bone and wound healing, minimize infection, and modify postoperative pain. There are few data available to confirm these claims. Prior to organized study, consistency and agreement in manufacture of the APG is needed. In this study, an attempt is made to isolate factors that are important in developing a consistent gel. A database review was performed to determine factors that affect PG quality and function. Quality was assessed by platelet count and fibrinogen concentration, whereas function was assessed by an arbitrary scale of gelling, in which a “1” was equal to a soup texture, “3” equal to a “Jell-O” consistency, whereas a grade of “2” was somewhere in between. Data specific to the blood draw and platelet-rich plasma sequestration were collected. Two hundred and sixty cases of APG production were reviewed. The volume of blood drawn was dependent on the machine used. Gelling of the APG was independent of platelet count and fibrinogen concentration. Gels that were rated soupy had an average platelet count of 540 K/μL ± 327 K/μL and a fibrinogen concentration of 225 mg/dL ± 76 mg/dL whereas a firm gel had an average platelet count of 486 K/μL ± 264 K/μL and a fibrinogen concentration of 229 mg/dL ± 78 mg/dL. The manner in which the blood was drawn along with the site from which the blood was drawn influenced the platelet concentration of the platelet-rich plasma. Optimal platelet counts were obtained when blood was drawn from a peripheral vein and sequestration was performed with the Medtronic Sequestra or the Medtronic Magellan. Ultimate gelling of PG is independent of fibrinogen and platelet concentrations. This work suggests a need for further research into the manufacture of APG.