bluuebunny/crossref_metadata_2025 huggingface dataset:
Reduction of conflictivity as a prerequisite for sustainable construction
Authors: Zaytseva L.I.
Published: July 2023

The transformation of project management approaches and business processes organization in crisis conditions requires rethinking and supplementing the concept of sustainable construction in terms of the socio-economic component, taking into account an important feature of the investment and construction sector - huge number of disputes and contradictions, the effective resolution of which depends on the successful implementation of projects.

The article suggests such an indicator as the degree of conflicts (conflictivity), which should supplement the sustainability indicators, and can be measured on the basis of the following factors: the dynamics of the number of economic disputes, the amount of conciliation agreements concluded at the stage of litigation, the result of consideration of insolvency (bankruptcy) cases, the number of terminated government contracts, business participation in the implementation of major projects, the degree of alternative dispute resolution popularity.
Situation and solutions for the construction industry in the trend of green economic development in Vietnam
Authors: Vu Phuong Ngan
Published: July 2023

The trend of developing a green economy is becoming a global trend and is supported and promoted by many countries and international organizations. The green economy focuses on sustainable development and minimizing negative impacts on the environment and natural resources. Around the world, many countries have launched plans and policies to promote the green economy, including the transition to renewable energy, waste treatment and reuse, enhancing energy efficiency and resources, encouraging the use of green products and services. The construction industry plays an important role in the economy but also contributes significantly to environmental pollution, resource use and carbon emissions globally. Developing the construction industry in a green economy is one of the important approaches to achieving sustainability in the construction sector. In Vietnam, the Government has launched many policies and plans to encourage the development of a green economy. Activities include promoting the use of renewable energy, promoting the use of electric vehicles and green products and services, improving air and water quality, and disposing of waste in a sustainable manner. The construction industry in particular has also begun to transition to a green building model, in which many construction works have been designed and built using international standards and certifications on green construction. However, the development of a green economy, including the construction industry, still faces many challenges, including high costs and lack of resources, as well as necessary changes in the way companies and organizations operate.
Development of composite panels based on porous glass aerogels for acoustic applications
Authors: Nguyen Minh-Ngoc , Nguyen Phuong-Lam , Nguyen Khac-Ky , Vu Viet-Dung , Trinh Van-Hai
Published: July 2023

In this work, we present the results of research on manufacturing composite materials based on porous glass beads for acoustic treatment. A new material with fire resistance, heat resistance, impermeability, longevity, and insulation is made from foam glass beads (made from waste glass) and cement mortar. Firstly, the composite concrete panels with a high level of porosity 66%–82% and spherical pores in millimeter scale (i.e., ranging from 0.15mm to 10mm) are fabricated. Then, acoustical measurements are performed to characterize the sound absorbing coefficient and the transport properties of the selected composite panels. The measurement data are compared to the semi-phenomenological Johnson-Champoux-Allard-Lafarge model to show a good agreement in terms of predicting the sound absorption property. From the obtained results it can be stated that the open porosity and the thickness of the fabricated materials affect strongly their sound absorption performance. Within a panel thickness of 33.3mm, the aerogel-based concrete panel can provide a good sound absorption coefficient which could be more than 0.60 in the frequency range of [820 1290]Hz and reach the value of 0.84 at a low resonance frequency of ~1032Hz. The methodology, therefore, enables the identification and validation of acoustical models for specific porous glass aerogel-based materials and paves the way for an efficient exploration of the parameter space for acoustical materials design.
Integrating the 14 Patterns of Biophilic Design into the convenience and comfort of apartments in Ho Chi Minh City
Authors: Nguyen Van Tin
Published: July 2023

Biophilic architecture is a growing field that seeks to create sustainable and healthy buildings that are in harmony with nature. Biophilic applications are expanding, where people are the center of design. The 14 Patterns of Biophilic Design is popular criteria of Biophilic architecture and widely applied, in which architectural solutions need to ensure the most convenient and comfortable living environment quality in a close relationship with nature. Apartment buildings in large cities of Vietnam such as Ho Chi Minh City are being developed strongly with many questions about the quality of the living environment. The goal of the article is to integrate the 14 Patterns of Biophilic Design into the convenience and comfort of apartments in Ho Chi Minh City. The research methods include: collecting documents, analysis-synthesis and modeling. The results focus on the proposed design solutions according to patterns of the 14 Patterns of Biophilic Design in each comfort level of the convenience and comfort of apartments. The study highlights the potential benefits of integrating biophilic design principles into the built environment in order to improve the overall health and well-being of urban residents. The conclusions will contribute to improving the quality of life in apartment buildings in Vietnam towards being more environmentally sustainable and humane.
Formation of City-like Structures while Ilya Golosov’s Creative Process
Authors: Adamov Oleg
Published: July 2023

It’s commonly recognized that Avant-garde creativity begins with almost complete negation and deconstruction of previous cultural background. But examination of architects’ creative work shows that such an act is preceded by their deep study of architectural history and form creation and derivation of their own sets of universal architectural forms and assemblage methods. The purpose of essay is to reconstruct the creative process of Avant-garde architect and to reveal the inclusion of forms, taken from architectural history and regarded as a cultural resource while city-like structures and architectural organisms becoming. The research uses a process approach to study architectural phenomena, interpreted as a further development of structuralism and post-structuralism methods, including analysis of an array of design data, modelling of dynamic structures and accounting the intrusions from alien contexts. Comparative analysis is also used to jointly consider borrowings from different historical contexts and avant-garde neologisms. As a result, it turns out that Golosov doesn’t break or deny, but mentally unscrews aggregate of historical forms to reintegrate the selected forms, in altered order, into the structure of new city-like complex. Hence, to harmonize his work he returns to composition and tectonics and refers to the historical contexts from where forms originated, and they evoke reminiscences.
Mechanisms and instruments of mutual integration of municipalities in the field of municipal infrastructure
Authors: Balashov Evgeni
Published: July 2023

The problems of modernization of municipal infrastructure are among the widely discussed in the national economic literature. There are significant advances in this direction, although quite a few unresolved problems remain. Much less attention is paid to the study of the complexity of municipal integration tools for the development of municipal infrastructure in the territorial and spatial environment. This article discusses trends and approaches to ensure the sustainable development and functioning of municipal infrastructure through the formation of mechanisms and tools for inter-municipal integration. The issues of the practical implementation of inter-municipal interaction in digital technologies format are highlighted. The necessity of creating and using a regional digital platform, based on which a structural model of a digital platform of inter-municipal integration can be formed is justified. The effects of inter-municipal integration in general in the sphere of housing and communal services are determined.
Increasing the environmental potential of territories through the implementation of redevelopment projects
Authors: Azhimov Timur , Manukhina Lyubov
Published: July 2023

The main idea of the article is to highlight the positive impact of redevelopment on ecology. Redevelopment is a process of transforming existing buildings, infrastructure, and land in urban areas. It is a crucial element in urban planning that aims to optimize land use and create sustainable and livable cities. In recent years, there has been a growing interest in sustainable urban development, and redevelopment has emerged as a potential solution to the challenges of urbanization. The redevelopment of underutilized or obsolete buildings and sites can help to reduce the environmental impact of urban areas by promoting energy efficiency, reducing carbon emissions, and conserving natural resources. Moreover, the use of modern technologies and sustainable building materials in redevelopment projects can lead to the creation of more eco-friendly buildings that are better adapted to the needs of the environment and the community. The involvement of local residents and stakeholders in the planning and execution of redevelopment projects can ensure that the projects are aligned with the needs and expectations of the community. In conclusion, the article emphasizes the importance of considering ecological factors in urban development and highlights the potential benefits of redevelopment in creating more sustainable and livable cities. By embracing redevelopment as a tool for urban regeneration, we can improve the quality of life for city dwellers, preserve natural resources, and reduce the environmental impact of urban areas.
Using Remote sensing and GIS to survey surface water in Hanoi, Vietnam
Authors: Phuong Le Thi Minh , Le Anh Vu , Huyen Le Thi Minh , Len Nguyen Thanh , Hiep Pham Ngoc , Linh Nguyen Thuy
Published: July 2023

Surface water plays a vital role in the living environment. The shrinking surface water area in urban areas is one of the main culprits causing serious environmental problems such as flooding, ecosystem imbalance, etc. In Vietnam, surface water area in the urban center is rapidly declining due to urbanization, especially in the capital - Hanoi, where the urbanization rate is highest. This study examines the mutation in surface water area in several central districts in Hanoi through the period of 1993-2020 using remote sensing images and GIS. The result shows that the surface water area in the research region decreased gradually over the years from 5881.2 hectares to 4328.7 hectares. This parameter dropped more steeply in recently established districts and those adjacencies namely Thanh Tri, Gia Lam, and Dong Anh than in central districts, Hoan Kiem and Hai Ba Trung for instance. Especially, In 2000 and 2007 the rate of reduction was highest. This finding is useful for urban planners, managers, and policymakers involved in Vietnam's sustainable urban development process.
Determining demand for water, water supply and drainage balance to wastewater reuse for urbans in Vietnam
Authors: Van Khanh Nghiem , Van Hien Nguyen , Anh Ta Hong , Thi Thu Ha Nguyen , Hong Van Nguyen
Published: July 2023

Wastewater reuse is very important in ensuring a stable water supply for the socio-economic development of cities in the future. That is even more meaningful for areas affected by climate change erratic, hot, arid, scarce and polluted due to different causes. Specifically, many regions and urban areas in Vietnam have not been proactive in water resources upstream; runoff through agricultural, industrial and urban areas contaminated by farming, industrial waste, wastewater and municipal solid waste. Based on published studies on the role and situation of wastewater reuse in urbans, as well as on legal documents Vietnam's current management related to wastewater drainage and reuse, the article presents how to calculate and determine the water demand in urban areas for calculating capacity of water supply plants; to set up the balance diagram of water supply and drainage for all types of urban areas (from special to grade V urbans) and the balance diagram of water supply and drainage in the works. The research results will be considered as a scientific basis for state management agencies as well as local authorities to appropriately and effectively use in formulating strategic orientations and objectives for urban water supply and drainage management in Vietnam urban areas.
Reasonable management and utilization of natural resources in the existing innovation and development of tier-four cities in Vietnam today
Authors: Trang Ha Thi Thuy
Published: July 2023

Urban planning and smart cities with smart, friendly, and reasonable infrastructure and institutional design suitable to people’s living standards. In Vietnam, urban planning and cities are now facing the risk the existing urban ecological land space and the available natural resources. Environmental problems and green cities are facing many difficulties. Therefore, Vietnam’s state administration has formulated policies to encourage investment, construction, and urban renovation. Reasonable management and utilization of natural resources in the existing innovation and development of tier-four cities have become a matter that needs to be researched and discussed. In this article, the author makes an assessment and comments on the reasonable management and utilization of natural resources in the existing innovation and development of tier-four cities in Vietnam. One of the challenges Vietnam’s state administration faces today is the available and potential investment opportunities of urban areas and cities.
Comparison of treatment technologies for highly concentrated nitrogen compound wastewater
Authors: Reshetova Anna , Gogina Elena
Published: July 2023

The flow of biogenic elements with wastewater into water bodies leads to an increase in the content of biogenic and organic compounds, a decrease in the oxygen content, the appearance of anaerobic zones, an increase in water turbidity, discoloration, pollution with microorganisms, including pathogenic ones, so the research area was the methods of treating wastewater that is highly loaded with nitrogen. Anammox process was considered as the most promising method of treating wastewater highly concentrated on nitrogen compounds. The analysis of the main existing technologies is carried out, the advantages, disadvantages and features of the application (operation) of these methods are revealed. The treatment of return streams as an alternative to the classical solution and an effective tool for improving the quality of wastewater treatment from nutrients is considered. The experience of implementation and operation of Anammox process at aeration stations in different countries is described.
Alternative energy development in the republic of Uzbekistan
Authors: Zaynalov Jahongir R. , Alieva Susanna S.
Published: July 2023

The purpose of this article is to study the conditions and actions for the use of alternative energy, mainly solar, in Uzbekistan, to find opportunities to accelerate this process. Therefore, the authors gave a description of the directions and prospects for the implementation of projects for the use of predominantly solar energy in Uzbekistan, studied the directions and prospects for its use, and provided criteria for the introduction of solar and wind energy. The authors noted that ensuring the development of alternative energy is carry out by ensuring the transformation of existing energy systems, taking into account new innovative technologies for generating electricity from renewable sources, as well as conducting new research to improve the efficiency of existing installations. Conclusions are formulated on expanding the use of solar and wind energy in Uzbekistan, which, according to the authors, will help in increasing the country's energy capacity.
Export potential of the Russian chemical complex products
Authors: Kiselev Vladimir , Savinkov Sergey , Danko Tamara , Tchaikovskaya Lyubov , Epstein Nikita , Tsenina Ekaterina
Published: July 2023

Nowadays, in modern conditions, the most important parameter for managing the development of complex economic systems (which is the chemical complex of the Russian Federation) is the assessment of the potential of the analyzed system. Being the part of this system structural elements, export potential plays an important role in the formation of the system viability, its provision with resources for development. The geopolitical situation of the modern period dramatically responds to the discussed structural element of the analyzed system: traditional logistics chains of goods distribution are interrupted and new logistics routes are formed as well. Problems arise with the legal accessibility of the supply of these products to target consumers of foreign countries and geographical regions contrary to international trade law and WTO institutional regulations with a significant amount of potential demand for the products of the system complex under discussion. Under these conditions, it is advisable to assess the export capabilities of the chemical complex of the Russian Federation, taking into account the negative effect of these environmental factors, giving preference to internationally friendly partnerships, logistics routes, terminals, types of transport systems, customs, cargo insurance systems, currencies, etc.
Environmental benefits of additive technologies
Authors: Bolotova Alina
Published: July 2023

The environmental movement, which began at the end of the 20th century and is now gaining more and more momentum, covers all spheres of society. Construction requires a large amount of natural resources, this is due to the increase in population and the acceleration of urbanization processes. Therefore, the problem of introducing environmentally friendly materials, energy-saving technologies, and “green standards” seems to be extremely important and relevant for the entire construction complex. The purpose of this article is to analyze and evaluate the world and national experience of introducing additive technologies into the construction process as the most environmentally friendly method for construction and operation. Based on the purpose of the scientific research, it is possible to identify the solution of the following tasks: analysis of research and development in the field of additive technologies to ensure the preservation of the environment, the use of statistical quality management tools to summarize the results. The article describes in detail the projects related to the construction of buildings and structures using additive technologies, analyzes the impact of this construction process on the environment. Environmental factors affecting 3D printing at each stage of the life cycle of the construction object are highlighted. The main environmental advantages of additive technologies and the problems of their implementation are identified.
Effective transformation of household savings in the context of a systemic economic crisis
Authors: Rogova Tatiana M. , Semenov Maxim A. , Chalova Alla Yu. , Tutaeva Dinara R. , Murzin Anton D.
Published: July 2023

The modern world is characterized by a high degree of digitalization, so citizens have access to an increasing variety of savings options. In just a few clicks, people can purchase shares of the largest companies, invest in real estate rental funds, open deposits in almost any bank, and purchase digital assets. However, financial literacy has not yet reached the level needed to use all financial instruments consciously. Since confidence in the banking and financial system is low, people save in cash, which slows economic growth. The study of various forms of savings and their reliability and availability can increase cashflow from individuals, triggering growth, especially in the current crisis conditions of 2020–2022, with unprecedented sanctions. The purpose of the study is to develop recommendations for the development of modern forms of effective savings for the population under the conditions of a systemic economic crisis. The study uses publicly available data on personal savings rates and relevant scholarly literature and uses the methods of analysis and synthesis, comparison, deduction, and statistical generalizations. In the course of the study, key savings trends and urgent income issues were identified, allowing for the formulation of several recommendations to improve the efficiency of modern savings methods.
The effect of interaction between international commodity markets and the Chinese stock market
Authors: Yansong Song , Njoroge Parmenas K. , Chernikova Valeria Dmitrievna , Trukhanov Stepan Vikentievich , Kasumova Dinara Marklenovna , Laamarti Yuliya Aleksandrovna
Published: July 2023

In light of COVID-19 and the extent of global economic interdependence, it is essential to understand risk spillover effects between China's stock market and international commodity market in order to optimize risk control and management and provide early warning. The aim of this research is to examine the spillover mechanisms between the Chinese stock market and the global commodity market using data from eleven specific industries. The results show that the Risk Spillover index of industrial and optional consumer industries in China's stock market is relatively high. This industry is more vulnerable to fluctuations in the international commodity market and is the main risk spillover industry; The energy and financial industries have great risk spillover effects on the international commodity market. The volatility spillovers between the Chinese stock market and the international commodity market are asymmetric: the Chinese stock market is mainly affected by the risk spillovers from gold and silver, while the international commodity market is mainly affected by the risk spillovers from the real estate, energy, and financial sectors. The results of this analysis can be used in future works to develop a risk hedging model to examine how bulk commodities differ in terms of portfolio weight, hedging ratio, and hedging efficiency.
Innovative and technological entrepreneurship in the context of sustainable development approaches
Authors: Zakharova Tatiana Ivanovna , Styurina Daria Evgenievna
Published: July 2023

Today, the sustainable development agenda is relevant not only as a factor of investment attractiveness for business, but also for the state as a whole. In the current situation, of course, it is important to stay the course towards the goals of sustainable development, but taking into account our own economic, socio-economic and technological interests. Many components of ESG are based on solving technological problems. At the same time, technologies and tools to a certain extent have reached their limit and can no longer provide the necessary level to solve the problem. In this regard, the role and relevance of innovative projects are increasing daily. This article is devoted to an overview of current views on the innovative design approach, in particular start-ups, in the context of sustainable development approaches.
Developing organizational goals in view of SMAACT goals model criteria
Authors: Suvaryan Arzik , Karapetyan Armine
Published: July 2023

The article is devoted to the study of goal setting methodology of a modern organization. This issue is relevant in the context of systemic changes of XXI century, as it generally leads to reassessing the philosophy of forming the management mechanism and goal setting methodology. Strategic management starts with the development of mission and goal setting. In order to set the goals it is necessary for any organization to determine the criteria in advance. A number of researchers have put forward theories regarding the issue of criteria for setting goals. This study outlines the approaches of the researchers including Andrew Grove (OKR), Edwin Locke and Garry Letham, Mark Murphy (HARD), David Van Roy (BSQ), Paul J. Meyer (SMART). Based on a comparative analysis of the approaches discussed in the article and other approaches, a unique approach for selecting criteria for the formation of SMAACT goals is proposed. According to the approach the goal should be specific, measurable, Act-small, achievable, controlling and time bound. In addition, based on the logic of complex strategic thinking, a matrix “goal – subgoal level – criterion” is formed. This matrix is the basis for creating the “Strategic Thinking Screen”. In the applied aspect, it allows an organization to form a systematic view of the compliance of goals and subgoals of all levels with the proposed six criteria (SMAACT).
Strategic analysis of information accessibility of tourist facilities in Russia
Authors: Khanina Anna , Yakimenko Marianna , Pryadko Irina , Hussein Abdullah , Mohmed Mostafa
Published: July 2023

The article presents a number of results of the research analysing information accessibility of tourist attractions in Russia. As part of the study, the authors have analysed touristic websites in federal districts that belong to popular Russian destinations. The analysis has showed that there is not any information resource fully adapted to all categories of tourists, in particular tourists with disabilities. The identified problems can form a basis for the development of recommendations for securing information accessibility of websites by tourists with disabilities, with the purpose to provide them with information about different facilities of tourism industry and touristic products/services and the ways to access them.
Trajectory of economic development of Bukhara region during digitalization
Authors: Tadjieva Sayyorakhon , Tokhirov Javlon , Khurramov Ortikjon , Juraeva Zilola , Khodjaeva Dilbar
Published: July 2023

This research demonstrates the beginning of the trajectory of the economic development of the Bukhara region during digitalization. Such indicators as the size of resident working-age population, the number of enterprises and organizations connected to the Internet, the length of fiber-optic communication lines, which are the factors affecting the growth of the gross regional product, have been analyzed based on the multifactorial econometric models. This research, along with the relevant literature review, provides opinions, conclusions and proposals of the authors of this research.
Features of digitalization of Russian regions
Authors: Stuken Tatiana , Lapina Tatiana , Korzhova Olga
Published: July 2023

Based on the materials of the Rosstat Monitoring of the Development of the Information Society in the Russian Federation for the period 2011-2020, the article analyzes the indicators characterizing the development of information and communication technologies. The purpose of the study is to assess the dynamics of business digitalization in Russian regions and digital divides. The main method of analysis is descriptive statistics. Based on the study of the indicators dynamics, the authors identified leading and outsider regions for various indicators of digitalization and built consolidated ratings of regions digitalization for 2011 and 2020. The study assessed the stability/mobility of the list of leading and outsider regions for the period under review, and considered the concentration of inequality and the relationship between business digitalization and the level of labor productivity in the region. Based on the results of the study, there was concluded that the mobility of the group of regions-leaders of digitalization is higher than those of the regions-outsiders. There is a fairly high concentration of low digitalization indicators in outsider regions, which, however, is stable over time. There is no significant relationship between the indicators of business digitalization and the level of labor productivity in the region, which to a certain extent confirms the productivity paradox known in the economic literature. On the other hand, the accelerated development of digitalization in regions with low levels of productivity and labor can be seen as an investment in the development of the region and in increasing labor productivity.
Precarization as a form of negative impact of digital transformation on the system of labor rights realization
Authors: Kurianov Nikolai
Published: July 2023

The processes of precarization actively developing at the present time are examined in this article. Precarization is considered to be the process of increasing the importance of atypical employment forms, accompanied by a decrease in the level of realization of labor rights and social protection of workers. The particular attention is paid to the problems of strengthening the precarization processes in the context of the development of various forms of labor activity organization based on the use of digital technologies. The most striking manifestation of the regulation lack of labor rights and, as a result, the development of precarization processes is manifested in relation to those categories of workers who offer their services to the consumer through “online platforms”. In this way, the article substantiates the need to separate these employees into a separate category and, as a result, the implementation of legal regulation of their rights and obligations, as well as the peculiarities of interaction with employers. At the same time, this article states the necessity of ensuring the adaptive orientation of the development of legal regulation systems of labor relations, which should be a barrier to the development of precarization processes in the context of the digital transformation of the entire socio-economic system.
Methodology for energy savings assessment, at engine oil change of road vehicles
Authors: Terziev Angel , Zlateva Penka , Ivanov Martin
Published: July 2023

The presented paper reveals the possibilities of the implementation of a methodology for evaluating energy savings, at changing the engine oil of different road vehicles. The purpose of the developed methodology is to provide an opportunity to evaluate the energy consumption before and after changing the engine oil of the vehicle. The conditions, the practical procedures and the mechanism for evaluating the energy savings after changing engine oils of vehicles are defined. Changing the engine oil of the car covers the replacement of the old oil with a new one within the maximum mileage determined by the manufacturer. The results of the application of the methodology for certain categories of cars allow an easy process of monitoring and verification. And finally, a computational example is considered, proving that the methodology gives correct results for the evaluation of energy savings, after the replacement of the engine oil of the vehicle.
The optimized power flow control system for the photovoltaic DC microgrid
Authors: Yusubov Elvin , Bekirova Lala
Published: July 2023

The power flow control systems play a significant role in DC microgrids with photovoltaic inputs to supply the load with continuous power. The output power of the photovoltaic modules could experience a decline due to fluctuations in solar irradiation and temperature, which necessitates the use of batteries and the utility grid to reduce the negative effects of undesirable variations. However, an efficient control strategy is necessary to ensure an uninterrupted energy supply to the load units. This paper proposes an improved control of energy flow based on a State-of-Charge battery power estimation technique using the Coulomb counting method. By accurately estimating the available power from the batteries using the State-of-Charge technique, the microgrid is able to determine to assess if it requires to switch to the grid when the power output from photovoltaic modules is insufficient to meet the load demand. The proposed method also eliminates the need for DC bus voltage level-based approaches to charge or discharge the batteries with the advantages of the significant reduction in DC bus voltage variations. The simulation results of the proposed approach show that it provides satisfactory control performance to meet the load demand.
Pollution of Varna Lake and possibilities of using the pollutants as resources
Authors: Ganchev Todor , Markova Valentina , Valcheva-Georgieva Ivalena , Dobrev Ivan
Published: July 2023

Varna Lake is of great social and economic importance for the city of Varna and the entire region. The urbanisation of the areas surrounding the Varna-Beloslav Lake complex and the accelerated industrialisation around the coastline of Varna Bay have significant anthropogenic pressure on the aquatic ecosystem. An essential aspect is that industrial development, maritime transport and urbanisation are substantial sources of large-scale inorganic and organic pollution with all the resulting negative consequences. Recent measurements show that the surface sediments, which are a source of nutrients for the water body of Varna Lake, are contaminated with heavy metals and oil products. In this paper, we present a quantitative assessment of the degree of contamination with heavy metals (Hg, As, Fe, Cu, Pb) and petroleum products in the upper sediments of Varna Lake and then discuss opportunities for using some of these pollutants as a resource. The exploitation of these resources would bring significant benefits for improving the ecological status of Varna Lake.
Study on behaviour of centrifugal pump driven by medium-voltage induction motor during operation control
Authors: Rachev Svilen , Dimitrova Kremena , Dimitrov Lyubomir
Published: July 2023

When studying electric drives, it is necessary to jointly analyze the processes in the electric power and control circuits of the electric motor as the main component determining the overall performance and in the mechanical executive part. The paper deals with the variation of the occurring torques, the currents flowing in the individual phases and the electrical power losses in the operation of a medium voltage electric drive of a pump unit from the point of view of energy efficiency. Emphasis is placed on the joint operation of the pump as a mechanism and the driving electric motor, studying the complete electromechanical system. During the studies, significant attention has been paid to the mathematical description and modeling with subsequent computer simulation of the ongoing electromagnetic and electromechanical processes. Different ways of controlling the motor have been applied - by softstarter and by frequency control. Also values for the duration of the start-up process have been obtained. Relevant conclusions have been drawn.
Results of the 2019 Survey on Perceptions of Vacancy and Turnover Among Perfusionists in the United States
Authors: Colligan Michael
Published: July 2023

A large number of recent publications and presentations have focused on impending workforce issues that surround the field of perfusion. Vacancy and turnover rates, which provide a picture of the current workforce status and serve as a benchmark for comparison with past and future equilibrium, have not been examined. The purpose of the 2019 Vacancy and Turnover study was to identify current staffing trends among a cohort of perfusionists in the United States, as well as the factors affecting these trends. A vacancy and turnover survey was conducted during January and February of 2019. The survey required participants to answer several questions designed to determine vacancy and turnover during the prior 1-year period. Questions related to the vacancy and turnover rates of perfusionists were reported with descriptive statistics, including the means, medians, standard deviations, and range of scores. The study collected 502 responses, of which 484 met all inclusion criteria. Vacancy and turnover rates were analyzed by state, region, employer type, group size, and salary range. In summary, the vacancy rate for all perfusion groups in this survey was 12.3%, with a turnover rate of 14.7%. This investigation explores differences in vacancy and turnover among different subgroups based on state, region, employer, practice size, and salary range. Data from this study are presented as a guide to assist stakeholders in determining the best course of action with regards to staffing of perfusion services and how to plan for future needs.
Letzter Ausweg Zeitarbeit?
Authors: Heeser Alexandra
Published: July 2023

Dünne Personaldecke und Ausfälle, die kompensiert werden müssen, sind Pflegealltag in Deutschland. Oft sind Zeitarbeitskräfte eine Lösung – gleichzeitig wird das Thema kontrovers diskutiert. Doch ist es möglich und sinnvoll, Zeitarbeit zu verbieten, oder gibt es Alternativen, um der Leasingspirale zu entkommen?
Optimization of the tunneling magnetoresistance and spin-valley polarization in complex magnetic silicene structures
Authors: Rodríguez-González R. , Díaz-Valerio L. A. , Molina-Valdovinos S. , Rodríguez-Vargas I.
Published: July 2023

Aperiodic order is ubiquitous in nature and quite relevant in science and technology. There are extensive works in aperiodic structures studying fundamental characteristics in physical properties, such as fractality, self-similarity, and fragmentation. However, there are fewer reports in which aperiodicity signifies an improvement in physical quantities with practical applications. Here, we show that the aperiodicity of fractal or self-similar type optimizes the tunneling magnetoresistance and spin-valley polarization of magnetic silicene structures, raising the prospects of spin-valleytronics. We reach this conclusion by studying the spin-valley-dependent transport properties of complex (Cantor-like) magnetic silicene structures within the lines of the transfer matrix method and the Landauer–Büttiker formalism. We find that the self-similar arrangement of magnetic barriers in conjunction with structural asymmetry reduces the conductance oscillations typical of periodic magnetic silicene superlattices and more importantly makes the K′-spin-down conductance component dominant, resulting in nearly perfect positive and negative spin-valley polarization states accessible by simply reversing the magnetization direction. The tunneling magnetoresistance is not as prominent as in periodic magnetic silicene superlattices; however, it is better than in single magnetic junctions. Furthermore, the optimization of the spin-valley-dependent transport properties caused by the complex structure is superior than the corresponding one reported in typical aperiodic structures, such as Fibonacci and Thue–Morse magnetic silicene superlattices.
Mass transfer of the multicomponent free jet and one numerical implementation on a graphic processing unit platform
Authors: Xu Shaofeng , Gu Lili , Fang Junlin , Zhang Yarong , Guo Ying , Shi Jianjun
Published: July 2023

Jet flows are ubiquitous in nature and laboratories. For example, helium and argon jets into ambient air are commonly used to produce atmospheric plasma jets. The jets before and after discharge both are typical multicomponent flows. This study reports on the implementation of a numerical solver based on the graphic processing units to model multicomponent mixture gas flows. To this end, two- and three-dimensional Jacobian matrices for the multicomponent Euler equations were obtained to reconstruct numerical fluxes and build a total variation diminishing scheme. The two-dimensional early-stage mass transfer of gas jets was studied for three mixture gases: He/air, Ar/air, and N2/air to numerically verify the steady functioning of the numerical solver despite the high mass fraction gradients. The mass fraction distribution of helium in ambient air exhibited more complex substructures than those of argon and nitrogen in ambient air. Using the watershed method, self-generated bullets were extracted from the mass fraction distributions of the helium jet. The proposed numerical solver implemented in this study is expected to provide a better understanding of gas jet dynamics, and the Jacobian matrices can provide a mathematical foundation for constructing potential higher schemes.
Resolution improvement of optoelectronic tweezers using patterned electrodes
Authors: Zaman Mohammad Asif , Wu Mo , Ren Wei , Jensen Michael A. , Davis Ronald W. , Hesselink Lambertus
Published: July 2023

An optoelectronic tweezer (OET) device is presented that exhibits improved trapping resolution for a given optical spot size. The scheme utilizes a pair of patterned physical electrodes to produce an asymmetric electric field gradient. This, in turn, generates an azimuthal force component in addition to the conventional radial gradient force. Stable force equilibrium is achieved along a pair of antipodal points around the optical beam. Unlike conventional OETs where trapping can occur at any point around the beam perimeter, the proposed scheme improves the resolution by limiting trapping to two points. The working principle is analyzed by performing numerical analysis of the electromagnetic fields and corresponding forces. Experimental results are presented that show the trapping and manipulation of micro-particles using the proposed device.
Separating signal from noise in wastewater data: An algorithm to identify community-level COVID-19 surges in real time
Authors: Keshaviah Aparna , Huff Ian , Hu Xindi C. , Guidry Virginia , Christensen Ariel , Berkowitz Steven , Reckling Stacie , Noble Rachel T. , Clerkin Thomas , Blackwood Denene , McLellan Sandra L. , Roguet Adélaïde , Musse Isabel
Published: July 2023

Wastewater monitoring has provided health officials with early warnings for new COVID-19 outbreaks, but to date, no approach has been validated to distinguish signal (sustained surges) from noise (background variability) in wastewater data to alert officials to the need for heightened public health response. We analyzed 62 wk of data from 19 sites participating in the North Carolina Wastewater Monitoring Network to characterize wastewater metrics around the Delta and Omicron surges. We found that wastewater data identified outbreaks 4 to 5 d before case data (reported on the earlier of the symptom start date or test collection date), on average. At most sites, correlations between wastewater and case data were similar regardless of how wastewater concentrations were normalized and whether calculated with county-level or sewershed-level cases, suggesting that officials may not need to geospatially align case data with sewershed boundaries to gain insights into disease transmission. Although wastewater trend lines captured clear differences in the Delta versus Omicron surge trajectories, no single wastewater metric (detectability, percent change, or flow-population normalized viral concentrations) reliably signaled when these surges started. After iteratively examining different combinations of these three metrics, we developed the Covid-SURGE (Signaling Unprecedented Rises in Groupwide Exposure) algorithm, which identifies unprecedented signals in the wastewater data. With a true positive rate of 82%, a false positive rate of 7%, and strong performance during both surges and in small and large sites, our algorithm provides public health officials with an automated way to flag community-level COVID-19 surges in real time.
Fast protein folding is governed by memory-dependent friction
Authors: Dalton Benjamin A. , Ayaz Cihan , Kiefer Henrik , Klimek Anton , Tepper Lucas , Netz Roland R.
Published: July 2023

When described by a low-dimensional reaction coordinate, the folding rates of most proteins are determined by a subtle interplay between free-energy barriers, which separate folded and unfolded states, and friction. While it is commonplace to extract free-energy profiles from molecular trajectories, a direct evaluation of friction is far more elusive and typically relies on fits of measured reaction rates to memoryless reaction-rate theories. Here, using memory-kernel extraction methods founded on a generalized Langevin equation (GLE) formalism, we directly calculate the time-dependent friction acting on the fraction of native contacts reaction coordinateQ, evaluated for eight fast-folding proteins, taken from a published set of large-scale molecular dynamics protein simulations. Our results reveal that, across the diverse range of proteins represented in this dataset, friction is more influential than free-energy barriers in determining protein folding rates. We also show that proteins fold in a regime where the finite decay time of friction significantly reduces the folding times, in some instances by as much as a factor of 10, compared to predictions based on memoryless friction.
Identification of a β-arrestin-biased negative allosteric modulator for the β
2
-adrenergic receptor
Authors: Ippolito Michael , De Pascali Francesco , Hopfinger Nathan , Komolov Konstantin E. , Laurinavichyute Daniela , Reddy Poli Adi Narayana , Sakkal Leon A. , Rajkowski Kyle Z. , Nayak Ajay P. , Lee Justin , Lee Jordan , Cao Gaoyuan , Donover Preston S. , Reichman Melvin , An Steven S. , Salvino Joseph M. , Penn Raymond B. , Armen Roger S. , Scott Charles P. , Benovic Jeffrey L.
Published: July 2023

Catecholamine-stimulated β
2
-adrenergic receptor (β
2
AR) signaling via the canonical G
s
–adenylyl cyclase–cAMP–PKA pathway regulates numerous physiological functions, including the therapeutic effects of exogenous β-agonists in the treatment of airway disease. β
2
AR signaling is tightly regulated by GRKs and β-arrestins, which together promote β
2
AR desensitization and internalization as well as downstream signaling, often antithetical to the canonical pathway. Thus, the ability to
bias
β
2
AR signaling toward the G
s
pathway while avoiding β-arrestin-mediated effects may provide a strategy to improve the functional consequences of β
2
AR activation. Since attempts to develop G
s
-biased agonists and allosteric modulators for the β
2
AR have been largely unsuccessful, here we screened small molecule libraries for allosteric modulators that selectively inhibit β-arrestin recruitment to the receptor. This screen identified several compounds that met this profile, and, of these, a difluorophenyl quinazoline (DFPQ) derivative was found to be a selective negative allosteric modulator of β-arrestin recruitment to the β
2
AR while having no effect on β
2
AR coupling to G
s
. DFPQ effectively inhibits agonist-promoted phosphorylation and internalization of the β
2
AR and protects against the functional desensitization of β-agonist mediated regulation in cell and tissue models. The effects of DFPQ were also specific to the β
2
AR with minimal effects on the β
1
AR. Modeling, mutagenesis, and medicinal chemistry studies support DFPQ derivatives binding to an intracellular membrane-facing region of the β
2
AR, including residues within transmembrane domains 3 and 4 and intracellular loop 2. DFPQ thus represents a class of biased allosteric modulators that targets an allosteric site of the β
2
AR.