bluuebunny/crossref_metadata_2025 huggingface dataset:
Pervious Concrete Reinforced with Waste Cloth Strips
Authors: Juradin Sandra , Mihanović Frane , Ostojić-Škomrlj Nives , Rogošić Ela
Published: February 2022

Pervious concrete is considered an environment-friendly paving material and its main feature is that it allows water to penetrate within its structure. Because of open pores in pervious concrete structures, there is a high risk of corrosion, so this concrete is used without any reinforcement or with fiber reinforcement. The incorporation of fibers in concrete is known to substantially increase the tensile strength, toughness, and ductility of concrete. The fast-fashion trend encourages people to buy more clothes and dispose of them in a shorter period of time, resulting in 85% of clothes ending up in landfills or being burned. In this paper, old cotton T-shirts were cut into narrow strips about 5 ± 1 cm long for the purpose of reinforcing pervious concrete. A total of eight concrete mixtures were made: four without reinforcement and four with textile-strip reinforcement. The number of textile strips was 1% of the total volume. Tests carried out on the specimens were: slump, density, porosity, compressive and flexural strength, water absorption, infiltration rate, and abrasion resistance. Multi-slice computed tomography (MSCT) was used for an X-ray examination and quantitative analysis of the specimens (ROI; region of interest) and 3D visualization (VRT; volume rendering technique). With an X-ray examination, the large holes in the cross sections of the specimens have been observed. They were caused by an insufficient compaction effort during the specimens’ placement, which affected the test results. Based on the obtained laboratory results, the waste strips improved the compressive strength, flexural strength, and abrasion resistance of the concrete with the addition of fine fractions, and generally increases the ductility of pervious concrete.
Mortality Risk Factors in Micro and Small Businesses: Systematic Literature Review and Research Agenda
Authors: Garcia Fabiane Tubino , ten Caten Carla Schwengber , de Campos Elaine Aparecida Regiani , Callegaro Aline Marian , de Jesus Pacheco Diego Augusto
Published: February 2022

Most micro and small businesses (MSEs) are limited in organizational structure, financial resources, technology, and management strategies. Due to these limitations, there are many risks involved in this sector. Understanding the aspects that contribute to the risk of mortality among MSEs is important to guide entrepreneurs in the development of strategic actions and to assist governments in the elaboration of policies that support the creation of new ventures. For this, it is important to know the key factors that contribute to the risk of business mortality. Thus, the following research questions emerge: What is the state of the art on the subject of business mortality in MSE? What are the factors that contribute to the risk of mortality in MSE? What is the relationship between the factors that contribute to the risk of mortality in MSE? The objective of this research was to analyze what the risk factors are for MSE mortality and how they are related to each other. From a systematic literature review, the state of the art on the topic of business mortality in MSEs was evidenced and its risk factors were identified. One hundred and six articles, published from January 2000 to February 2021, were analyzed. The results showed 36 mortality risk factors and highlighted the risks associated with innovative processes, business management, and the characteristics of the entrepreneur. This study contributes to a theoretical framework on corporate mortality and provides an agenda for future research, showing gaps to be explored. In terms of managerial implications, we suggest that entrepreneurs prioritize training initiatives, investing in education, that MSEs participate in cooperation networks to establish partnerships between stakeholders, and that they invest in technological tools to make companies more competitive in the market.
Examining Generation Z’s Attitudes, Behavior and Awareness Regarding Eco-Products: A Bayesian Approach to Confirmatory Factor Analysis
Authors: Nikolić Tatjana Mamula , Paunović Ivan , Milovanović Mirjana , Lozović Nenad , Đurović Marija
Published: February 2022

The research examines Generation Z’s (Gen Z’s) attitudes, behavior and awareness regarding sustainability-oriented products in two European countries, located in the region of Western Balkans, Bosnia–Herzegovina and Serbia. The research deploys generational cohort theory (GCT) and a quantitative analysis of primary data collected through an online questionnaire among 1338 primary, high school and university students, all belonging to Generation Z. It deploys a Confirmatory Factor Analysis (CFA) by running both Maximum Likelihood (ML) and Markov Chain Monte Carlo (MCMC) procedures, the latter being suitable for binary variables, which have been deployed in the study. The results of MLCFA provide evidence that there is a statistically significant and relatively strong relation between sustainability and circular economy attitudes (SCEA) and sustainability and circular economy behavior (SCEB), while there is a statistically insignificant and relatively weak relation between sustainability and circular economy behavior (SCEB) and circular economy awareness (CEW). The results of the BCFA, which is based on MCMC procedure, are similar to the results based on a rather commonly used MLCFA procedure. The results also confirm that Gen Z knows more about the companies which recycle products than it does about the CE as a concept, while the vast majority is concerned about the future of the planet and is motivated to learn more about the CE through CE and various awareness-raising measures.
The Effects of Natural Zeolite as Fly Ash Alternative on Frost Resistance and Shrinkage of Blended Cement Mortars
Authors: Milović Tiana , Šupić Slobodan , Malešev Mirjana , Radonjanin Vlastimir
Published: February 2022

As the cement industry is responsible for 7% of the global CO2 emissions, locally and abundantly available materials are vastly valorized, and their use is assuming a significant role in this domain. Over the last few decades, significant research in the development of supplementary cementitious materials (SCMs) derived from industrial wastes, such as fly ash (FA), has been conducted. However, facing environmental pressures, coal power plants are closing across the planet. Hence there is an urgent need to identify sustainable SCMs that can replace FA in the concrete industry. Furthermore, the usage of FA in cement-based composites does not often produce satisfactory results from the aspect of certain properties, such as freeze–thaw durability. Therefore, the application of natural zeolites (NZs) for these purposes has emerged as an area of interest in the civil engineering practice. This paper presents the results of experimental research regarding the influence of NZ, as a mineral admixture, on the basic physical and mechanical properties of cement mortars, with a focus on frost resistance and drying shrinkage. The amount of NZ was varied from 10 to 30% in relation to cement mass. The findings indicate that NZ positively influences the drying shrinkage reduction regardless of the replacement level, while the best results concerning frost resistance can be achieved in cement blends with 10% NZ.
Thermal Characteristics Simulation of an Energy-Conserving Facade: Water Flow Window
Authors: Lyu Yuanli , Chen Sihui , Liu Can , Li Jun , Li Chunying , Su Hua
Published: February 2022

In this paper, a 3D numerical simulation was completed to explore the thermal characteristics in a water flow window in-depth. CFD was used to carry out the analysis on top of successful validation. By changing the solar intensity, water supply temperature and velocity, the temperature distribution and flow field in the window cavity, as well as the water heat gain, were analyzed and compared. This is meaningful for improving the energy-conserving performance in building applications. Simulation results reveal that the variation of solar intensity and water supply temperature affects directly the temperature distribution and the water heat gain but has little impact on the overall velocity field. Local vortices are generated in the window cavity, and their formation and location are largely affected by the varied temperature rise in the water layer. The water heat gain increases and then decreases with the increase in water supply velocity. In addition, a large-enough water supply velocity can disorder the uniform upward flow. These are detrimental to effective thermal extraction. Therefore, in practical application, the vortex should be eliminated, and the flow velocity should be determined properly to maximize the water heat gain.
Research on Energy Consumption Constitution and Energy Efficiency Strategies of Residential Buildings in China Based on Carbon Neutral Demand
Authors: Sun Wanghu , Sun Yuning , Xu Li , Chen Xing , Zai Debin
Published: February 2022

To assist in the implementation of carbon peaking and carbon neutrality in China, due to the contradiction between the increasing energy consumption of residential buildings in China and the higher energy efficiency goals, this paper illustrates that the energy consumption constitution of residential buildings in the whole life cycle and then puts forward comprehensive energy efficiency strategies. With literature and statistical data, the main part of building energy consumption lies in the materialization and use phases, which both will be continually increasing, and divided into energy utilization and waste. By inducing the energy consumption in the use phase, the energy consumption of residential buildings can be further classified into the energy consumption of indoor environments, residential behavior, and public facilities, where the internal factor of continuous increase are all elaborated. Via the analysis of energy waste causes, this paper constructs a model of energy consumption in residential buildings, reveals that the key to energy efficiency in residential buildings lies in scientific decision-making, lifestyle improvement, and appropriate energy efficiency technologies and measures adoption, and points out that promoting building energy efficiency through the whole life cycle of buildings and building activities is needed to achieve carbon compliance and carbon neutrality.
Building a Super Smart Nation: Scenario Analysis and Framework of Essential Stakeholders, Characteristics, Pillars, and Challenges
Authors: Penmetsa Murali Krishna , Bruque Camara Sebastian Juan
Published: February 2022

Globally, countries are increasingly facing challenges regarding their national future post the COVID-19 pandemic with respect to decreasing and aging populations; dwindling workforces; trade wars due to restricted movement of goods, people, and services; and overcoming economic development and societal problems. Accordingly, we identify the challenges and corresponding solutions that act as pillars for a framework to build a super smart nation. We analyze 73 peer-reviewed research papers from Scopus index databases and use the Delphi methodology to identify the challenges, which include people and society, robots, technology, research and innovation, digital infrastructure, data, politics, governance, and sustainability. Further, we discuss the relevant solutions, including top leadership motivation and commitment; proactive steps from the government, development of policies; legal frameworks and laws; creation of awareness programs; use of advanced technologies (such as robotics and semantic technologies); and development of interoperable infrastructure; innovation ecosystem; sustainable energy sources; and global standards for education system through transformation of the education system. These novel insights have valuable practical and theoretical implications for guiding policymakers, industry leaders, and researchers in building a super smart nation.
What Are the Sectors Contributing to the Exceedance of European Air Quality Standards over the Iberian Peninsula? A Source Contribution Analysis
Authors: Jiménez-Guerrero Pedro
Published: February 2022

The Iberian Peninsula, located in southwestern Europe, is exposed to frequent exceedances of different threshold and limit values of air pollution, mainly related to particulate matter, ozone, and nitrous oxide. Source apportionment modeling represents a useful modeling tool for evaluating the contribution of different emission sources or sectors and for designing useful mitigation strategies. In this sense, this work assesses the impact of various emission sectors on air pollution levels over the Iberian Peninsula using a source contribution analysis (zero-out method). The methodology includes the use of the regional WRF + CHIMERE modeling system (coupled to EMEP emissions). In order to represent the sensitivity of the chemistry and transport of gas-phase pollutants and aerosols, several emission sectors have been zeroed-out to quantify the influence of different sources in the area, such as on-road traffic or other mobile sources, combustion in energy generation, industrial emissions or agriculture, among others. The sensitivity analysis indicates that large reductions of precursor emissions (coming mainly from energy generation, road traffic, and maritime-harbor emissions) are needed for improving air quality and attaining the thresholds set in the European Directive 2008/50/EC over the Iberian Peninsula.
Regulation and Optimization of Urban Water and Land Resources Utilization for Low Carbon Development: A Case Study of Tianjin, China
Authors: Jiang Wenyuan , Zeng Zhenxiang , Zhang Zhengyun , Zhao Yichen
Published: February 2022

The consumption of energy and resources produces carbon emissions and exacerbates global warming. As the basic resources for urban development, the development and utilization of water and land resources consume a large amount of energy, which results in carbon emissions. This paper presents a study aimed at analyzing the interaction of urban water–land–energy and its carbon emission effects and finding ways to achieve the win-win situation of carbon emission reduction and economic development. We used an SD-MOP model combined with system dynamics (SD) and multi-objective programming (MOP) to describe the feedback relationship between urban water and land resources utilization and carbon emissions, designed a comprehensive scheme for carbon emission reduction goal and optimized it in order to achieve the low carbon development goal. Tianjin, one of the four province-level municipalities, was investigated as a case study for this research. The simulation results indicate that Tianjin’s carbon emissions from water and land utilization will peak around 2025 when applying the comprehensive regulation scheme. After optimization, the optimal regulation scheme would achieve considerable social, economic and environmental benefits. We suggest the implementation of measures including the optimization of the industrial, energy and land use structure; the improvement of energy efficiency; increasing residents’ low carbon awareness; and strengthening industrial and domestic water savings to realize the low carbon development of the city. The findings of this study will be useful for the management of urban water and land utilization.
Innovative Development Finance for Health Sector Development: Focusing on the Air Ticket Solidarity Levy System in the Republic of Korea
Authors: Song Jisun , Pyun Lynn
Published: February 2022

Financial sustainability has been a perennial problem in international development. Furthermore, among different areas of developmental support, securing sufficient financial resources is particularly significant in the health sector where people’s very lives are at stake. Given the above, we examine innovative development finance (IDF) for the health sector with a particular focus on the air ticket solidarity levy system in the Republic of Korea. After an overview of the origins and the present state of the solidarity tax system, we explain how it was implemented in the context of South Korea’s health ODA (Official Development Assistance). A first-ever health ODA stakeholders’ perception survey with its implications on the airplane tax system follows. For policy suggestions, we suggest incorporating a COVID-19 agenda into the Global Disease Eradication Fund (GDEF) immediately, and to raise public awareness in a timely fashion. We believe the Korean case is significant for both its direct impact in the Eurasian region as an emerging donor, and for its unique position due to its middle-power status whose trajectory could serve as an example to many other nations seeking sustainable financial schemes.
The Relationship between Circular Economy, Industry 4.0 and Supply Chain Performance: A Combined ISM/Fuzzy MICMAC Approach
Authors: Godinho Filho Moacir , Monteiro Luiza , de Oliveira Mota Renata , dos Santos Leite Gonella Jessica , de Souza Campos Lucila Maria
Published: February 2022

This paper aims to assess the relationship between Industry 4.0 (I4.0) and the circular economy that could contribute to supply chain management performance. To achieve this, a combination of the interpretative structural modelling (ISM) and (cross-impact matrix multiplication applied to classification) MICMAC approach was used to establish the interrelationships between these topics. The developed analysis reveals that there are 19 constructs capable of elucidating this relationship and that there is a hierarchy between these constructs, which are presented in a structural model. Further, the different levels of dependency and driving power are compared in a cluster diagram. As the main result, it was found that there is a strong mutual relationship between the basic technologies. The use of Internet of Things and cloud computing technologies influences the collection of large amounts of data, leading to big data, which in turn influence the use of data analytics tools to obtain competitive advantages. These outcomes may contribute to managers’ more assertive decision-making regarding the selection, implementation, and evaluation of projects adopting Industry 4.0 technologies and circular economy approaches in supply chains. Moreover, our study could be the basis for future empirical research to investigate how companies incorporate Industry 4.0 technologies into their processes and how this influences the quest for sustainable supply chains.
Data-Center Farming: Exploring the Potential of Industrial Symbiosis in a Subarctic Region
Authors: Cáceres Cristina Ramos , Törnroth Suzanna , Vesterlund Mattias , Johansson Andreas , Sandberg Marcus
Published: February 2022

As our world becomes increasingly digitalized, data centers as operational bases for these technologies lead to a consequent increased release of excess heat into the surrounding environment. This paper studies the challenges and opportunities of industrial symbiosis between data centers’ excess heat and greenhouse farming, specifically utilizing the north of Sweden as a case study region. The region was selected in a bid to tackle the urgent urban issue of self-sufficiency in local food production. A synergetic approach towards engaging stakeholders from different sectors is presented through a mix of qualitative and quantitative methods to facilitate resilient data-center-enabled food production. The paper delivers on possible future solutions on implementing resource efficiency in subarctic regions.
Climate Warming-Induced Changes in Plant Phenology in the Most Important Agricultural Region of Romania
Authors: Bandoc Georgeta , Piticar Adrian , Patriche Cristian , Roșca Bogdan , Dragomir Elena
Published: February 2022

Changes in plant phenology are a direct indicator of climate change and can produce important consequences for agricultural and ecological systems. This study analyzes changes in plant phenology in the 1961–2010 period (for both the entire interval and in three successive multi-decades: 1961–1990, 1971–2000 and 1981–2010) in southern and southeastern Romania, the country’s most important agricultural region. The analysis is based on mean monthly air temperature values collected from 24 regional weather stations, which were used for extracting the length (number of days) of phenophases (growing season onset, budding–leafing, flowering, fruiting, maturing, dissemination of seeds, start of leaf loss, end of leaf loss) and of the overall climatic growing season (CGS, which includes all phenophases), by means of the histophenogram method. Using a number of reliable statistical tools (Mann–Kendall test, Sen’s slope estimator and the regression method) for exploring annual trends and net (total) changes in the length of the phenological periods, as well as for detecting the climate—growing season statistical relationships, our results revealed complex phenology changes and a strong response in phenological dynamics to climate warming. Essentially, a lengthening of all phenophases (maximal in the maturing period, in terms of statistical significance and magnitude of trends—on average 0.48 days/yr/24 days net change in the 1961–2010 period, or even 0.94 days/yr/28 days net change in the 1971–2000 sub-period) was noticed, except for the fruiting and dissemination phenophases, which were dominated by negative trends in the number of days, but partially statistically significant (at a confidence level threshold of at least 90%). The CGS exhibited overall increasing trends, with an average of 0.21 days/yr/11 days net change in the 1961–2010 interval, and even of 0.90 days/yr/27 days net change in the 1981–2010 sub-period. Moreover, based on the slope values obtained upon application of a linear regression to mean temperature and CGS, we discovered that a 1 °C increase in climate warming accounted for a remarkable lengthening of the CGS, on average of 14 days between 1961 and 2010, and of 16 days between 1981 and 2010. Our results can help improve the adaptation of agroecological systems to future climate change.
Analysis of the Influential Factors towards Adoption of Car-Sharing: A Case Study of a Megacity in a Developing Country
Authors: Safdar Muhammad , Jamal Arshad , Al-Ahmadi Hassan M. , Rahman Muhammad Tauhidur , Almoshaogeh Meshal
Published: February 2022

Motorization has been escalating rapidly in developing countries, posing a severe challenge to sustainable urban mobility. In the past two decades, car-sharing has emerged as one of the most prominent alternatives to facilitate smart mobility solutions, thereby helping to reduce air pollution and traffic congestion. However, before its full-scale deployment, it is essential to understand the consumers’ acceptance of car-sharing systems. This study aimed to assess the public perception and acceptance of the car-sharing system through a stated preference (SP) questionnaire in the city of Lahore, Pakistan. The collected data contained detailed information on various service attributes of three alternative modes (car-sharing, private car, and taxi) in addition to the sociodemographic attributes of respondents. Data analysis and interpretation were performed using econometric models such as the Multinomial Logit Model (MNL), the Nested Logit Model (NL), and the Random Parameter Logit Model (RPL). Study findings revealed that several generic attributes such as travel time, travel cost, waiting time, and privacy were predicated as significant influential factors towards the adoption of car-sharing. Sociodemographic attributes, including age, education, monthly income, the individuals who had driver’s licenses, and frequency of travel in a week, were also found to be significant. The findings of the current study can provide valuable insights to stakeholders and transportation planners in formulating effective policies for car-sharing.
A Statistical Analysis of the Migration Process: A Case Study—Romania
Authors: Pripoaie Rodica , Cretu Carmen-Mihaela , Turtureanu Anca-Gabriela , Sirbu Carmen-Gabriela , Marinescu Emanuel Ştefan , Talaghir Laurentiu-Gabriel , Chițu Florentina , Robu Daniela Monica
Published: February 2022

The research aims at studying and predicting the migration process in Romania over the last 20 years and at identifying the impact of the COVID-19 pandemic. The study analyzes several models for estimating migration through linear regression, but also a VAR (Vector autoregression) analysis, as the variables can influence each other. Vector autoregression (VAR) is also used to model multivariate time series, and it can analyze the dynamics of a migration process. Therefore, the best model for forecasting the migration process in Romania is Model 1 of linear regression. This phenomenon generates many positive and negative economic, demographic and political effects. The migration process has become particularly important for Romania in the last 20 years, and its socio-economic, political and cultural effects affect the Romanian state. That is why flexible policies are needed in order to be coherent, to have as main purpose keeping specialists in the country in certain basic economic fields, as well to implement measures to determine the return of specialists and students who have left to study abroad.
A Preliminary Studies of the Impact of a Conveyor Belt on the Noise Emission
Authors: Bortnowski Piotr , Król Robert , Nowak-Szpak Anna , Ozdoba Maksymilian
Published: February 2022

This article performs a comparative analysis of noise generated by conveyor belts with different design parameters. The study was conducted for belts with the same tensile strength, differing in the physical parameters of the cover rubber. Noise emission measurements were performed on a laboratory belt conveyor. The test on the stand allowed for the determination of the noise emission as a function of variable operating parameters: the tensioning force and linear speed of the belt. Research results indicated a significant impact of speed on the emitted noise. The effect of belt tension on noise emission is small, and it is definitely less significant than the effect of linear speed. The results also show that it is possible to select a conveyor belt that emits less noise under the same operating conditions. The analysis of the results allowed us to determine the impact of the physical parameters of the belt covers on the emitted noise.
A CFD Analysis for Novel Close-Ended Deflector for Vertical Water Turbines
Authors: Al-quraishi Mohammed Baqer Zaki Yahya , Sarip Shamsul , Mad Kaidi Hazilah , Ardila-Rey Jorge Alfredo , Muhammad-Sukki Firdaus
Published: February 2022

The effects of climate change are growing more and more evident, and this is caused by the increase in CO2 emissions. Fossil fuel exhaustion and the need for electricity in remote areas have encouraged researchers to advance and develop the renewable energy sector. One type of clean energy technology is vertical water turbines that have low efficiency. This paper aims to design and simulate a novel close-ended, guided deflector to improve the efficiency of vertical turbines. This research used the dynamic mesh technique to evaluate the concept after the deflector was designed, and a grid independence study, a boundary sensitivity study, and a timestep sensitivity study were implemented to ensure the accuracy of the results. Then, we used the sliding mesh model to determine the performance of four rotors. The results from the dynamic mesh model showed that the straight rotor with the proposed deflector was not suitable for operating in the deflector, and the concept is static and does not rotate. However, the others showed a valid concept in the proposed deflector. For the sliding mesh technique, the results indicated a common trend: all the rotors’ performances increased when tip speed ratio (TSR) increased, and the highest amount of the power coefficient (Cp) was found at higher TSRs, such as 1.3 and 1.4, with around 0.45 in the cross flow type. A three-dimensional simulation was conducted of the cross flow type with the proposed deflector, and a similar trend was found. Nevertheless, around a 5% difference was found between the 3D and 2D results for cross flow. The deflector can significantly improve the performance after 0.7 TSR to reach over 0.42 Cp at 1.3 TSR, whereas, without the deflector, the performance reduces to approximately 0.1 Cp at the same TSR.
Mobile-Energy-as-a-Service (MEaaS): Sustainable Electromobility via Integrated Energy–Transport–Urban Infrastructure
Authors: Vilathgamuwa Mahinda , Mishra Yateendra , Yigitcanlar Tan , Bhaskar Ashish , Wilson Clevo
Published: February 2022

The transport sector is one of the leading contributors of anthropogenic climate change. Particularly, internal combustion engine (ICE) dominancy coupled with heavy private motor vehicle dependency are among the main issues that need to be addressed immediately to mitigate climate change and to avoid consequential catastrophes. As a potential solution to this issue, electric vehicle (EV) technology has been put forward and is expected to replace a sizable portion of ICE vehicles in the coming decades. Provided that the source of electricity is renewable energy resources, it is expected that the wider uptake of EVs will positively contribute to the efforts in climate change mitigation. Nonetheless, wider EV uptake also comes with important issues that could challenge urban power systems. This perspective paper advocates system-level thinking to pinpoint and address the undesired externalities of EVs on our power grids. Given that it is possible to mobilize EV batteries to act as a source of mobile-energy supporting the power grid and the paper coins, and conceptualize a novel concept of Mobile-Energy-as-a-Service (MEaaS) for system-wide integration of energy, transport, and urban infrastructures for sustainable electromobility in cities. The results of this perspective include a discussion around the issues of measuring optimal real-time power grid operability for MEaaS, transport, power, and urban engineering aspects of MEaaS, flexible incentive-based price mechanisms for MEaaS, gauging the public acceptability of MEaaS based on its desired attributes, and directions for prospective research.
Driving Factors of Economic Diversification in Resource-Rich Countries via Panel Data Evidence
Authors: Jolo Abdulrahman M. , Ari Ibrahim , Koç Muammer
Published: February 2022

Economic diversification is an essential aspect of sustainable development as diversification enhances macroeconomic stability and promotes structural and long-term transformation not only in the economy but also in other pillars of development such as social institutions and dimensions. There is empirical evidence suggesting an impact of economic and structural factors on diversification. However, there is no consensus on the results in the literature because of various factors, such as the employment of different variables, methodologies, countries, and periods. This paper empirically explores the relations driving economic diversification in 14 resource-rich countries between 2001 and 2019, with six alternative models. In this regard, feasible generalized least squares regression was employed for the proposed model specifications. It provides strong evidence that gross capital formation, financial development, labor force participation, education, and the rule of law have statistically significant and positive impacts on economic diversification performance. On the other hand, inward foreign direct investment, real GDP growth, and self-employment rate also have statistically significant, but negative, impacts on economic diversification, probably because they further promote or are a result of resource-based growth rather than diversification into other technology- and knowledge-based sectors.
New Antifriction Composites for Printing Machines Based on Tool Steel Grinding Waste
Authors: Roik Tetiana , Gavrysh Oleg , Rashedi Ahmad , Khanam Taslima , Raza Ali , Jeong Byongug
Published: February 2022

In this article, we present research results on the structure and properties of new self-lubricating antifriction composites based on 4H4VMFS tool steel grinding waste with solid lubricant additives. The new composites are designed to work in the friction units of offset cylinders in printing machines at rotation speeds up to 7000 rpm and increased loads up to 5.0 MPa. The developed technology formed composites with a fine-grained heterophase structure with a metal matrix base of tool steel 4H4VMFS regenerated grinding waste, consisting of high-alloy α−solid solution and hard grains of alloying element carbides, as well as evenly distributed CaF2 antiseizure solid lubricant. This structure ensured the formation of composites with favorable functional properties. During the friction process, antiseizure films were formed on the contact surfaces, resulting in a self-lubrication mode. Comparative tests for friction and wear showed significant advantages of the new waste composite compared to cast bronze parts, which are traditionally used in the friction units of offset cylinders of rolled newspaper printing machines. The stable operation of the new composite made it possible to ensure a “wear-free” effect. Studies have shown the importance and prospects of using the wide range of valuable grinding waste in the reproduction cycle to manufacture quality composites. Reuse of such waste would significantly protect the environment from pollution connected with human activity industrial and mitigate negative impacts on ecosystems and the biosphere.
On the τ Decomposition Method for the Stability and Bifurcation of the TCP/AQM Networks versus Time Delay
Authors: Jin Hui-Long , Di Tian-Le , Yu Hong , Zhang Ran-Ran
Published: February 2022

This paper investigates the nonlinear dynamics of Transmission Control Protocol and Active Queue Management (TCP/AQM) networks, including the local stability and periodic bifurcation. The parameter of transportation delay affects the stability of the dynamical systems. One of the purposes of our work is to determine the delay stable interval of the transportation network. It is found that there is only one critical value of network delay by the τ decomposition technique. When the delay passes the critical point, the system performs Hopf bifurcation with a pair of symmetry with purely imaginary roots (PIR). In addition, the other purpose is to consider the stability of bifurcating periodic solutions. Combining with τ-decomposition strategy and central manifold theory, the issues of delay stable interval and stability of Hopf bifurcation are all tackled. Finally, numerical examples are illustrated to show the accuracy and effectiveness of the proposed method.
Temperature and Thermal Energy of a Coronal Mass Ejection
Authors: Bemporad Alessandro
Published: February 2022

Due to the scarcity of UV–EUV observations of coronal mass ejections (CMEs) far from the Sun (i.e., at heliocentric distances larger than 1.5 Rsun) our understanding of the thermodynamic evolution of these solar phenomena is still very limited. This work focuses on the analysis of a slow CME observed at the same time and in the same coronal locations in visible light (VL) by the MLSO Mark IV polarimeter and in the UV Lyman-α by the SOHO UVCS spectrometer. The eruption was observed at two different heliocentric distances (1.6 and 1.9 Rsun), making this work a test case for possible future multi-slit observations of solar eruptions. The analysis of combined VL and UV data allows the determination of 2D maps of the plasma electron density and also the plasma electron temperature, thus allowing the quantification of the distribution of the thermal energy density. The results show that the higher temperatures in the CME front are due to simple adiabatic compression of pre-CME plasma, while the CME core has a higher temperature with respect to the surrounding CME void and front. Despite the expected adiabatic cooling, the CME core temperatures increased between 1.6 and 1.9 Rsun from 2.4 MK up to 3.2 MK, thus indicating the presence of plasma heating processes occurring during the CME expansion. The 2D distribution of thermal energy also shows a low level of symmetry with respect to the CME propagation axis, possibly related with the CME interaction with nearby coronal structures. This work demonstrates the potential of UV and VL data combination and also of possible future multi-slit spectroscopic observations of CMEs.
Methodology for Measuring the Cutting Inserts Wear
Authors: Daicu Raluca , Oancea Gheorghe
Published: February 2022

In the industrial manufacturing, the wear of the cutting tool represents the main factor that causes machine downtime and it has a negative influence over the machined surface roughness and dimensional and position deviations. For this reason, the accurate measurement of tool wear both on-line (during machining) and off-line (outside of the machining process) is a necessity. Due to the continuous technology innovation, finding new and more effective methods to measure precisely the wear represents a permanent interest for research. In this paper, after a review of recent developed methods in this field, showing the methods of measuring wear and indicating the error sources when measuring the wear of cutting inserts, the necessity to have a unitary methodology for measuring the flank wear is emphasized. Applying it could obtain the same wear-measured values in the same conditions. For this purpose, the measurement errors are determined, and a new methodology for measuring the cutting insert wear is developed. It was tested in the case of six worn cutting inserts used for the turning process of specimens (1C45 steel), of 50 mm diameter and 300 mm length. By testing the developed methodology, it was found that the errors that can be made by various researchers while measuring wear are acceptable, leading to results that can be considered correct from a practical point of view. In the paper is also presented how the principle of symmetry is used to characterize the wear of the cutting inserts.
On the Ray-Wavefront Duality
Authors: Díaz-Cano Antonio , González-Gascón Francisco , Sánchez-Soto Luis L.
Published: February 2022

We investigate the behavior of the solutions of the ray equation in isotropic media. We discuss local and global transversals and wavefronts and give examples of rays without wavefronts.
De Rerum (Incerta) Natura: A Tentative Approach to the Concept of “Quantum-like”
Authors: Facco Enrico , Fracas Fabio
Published: February 2022

In recent years, the term “quantum-like” has been increasingly used in different disciplines, including neurosciences, psychological and socio-economical disciplines, claiming that some investigated phenomena show “something” in common with quantum processes and, therefore, they can be modeled using a sort of quantum formalism. Thus, the increasing use of the term “quantum-like” calls for defining and sharing its meaning in order to adopt it properly and avoid possible misuse. There is a fil rouge linking both pre-Socratic and Eastern philosophies and quantum physics, suggesting an epistemological symmetry between them. In our opinion, the concept of “quantum-like” may be successfully applied to macroscopic phenomena and empirical sciences other than physics when the following two conditions are satisfied: (a) the behavior of the investigated phenomena show logical analogies with quantum phenomena; (b) it is possible to find a criterion of truth based on an experiential/scientific approach applied to a probabilistic model of description of the phenomena. This is only a first small step in the approach to the concept of “quantum-like”, which will hopefully be helpful in promoting further discussion and achieving a better definition.
Relativistic Magnetized Astrophysical Plasma Outflows in Black-Hole Microquasars
Authors: Papavasileiou Theodora , Kosmas Odysseas , Sinatkas Ioannis
Published: February 2022

In this work, we deal with collimated outflows of magnetized astrophysical plasma known as astrophysical jets, which have been observed to emerge from a wide variety of astrophysical compact objects. The latter systems can be considered as either hydrodynamic (HD) or magnetohydrodynamic (MHD) in nature, which means that they are governed by non-linear partial differential equations. In some of these systems, the velocity of the jet is very high and they require relativistic MHD (RMHD) treatment. We mainly focus on the appropriate numerical solutions of the MHD (and/or RMHD) equations as well as the transfer equation inside the jet and simulate multi-messenger emissions from specific astrophysical compact objects. We use a steady state axisymmetric model assuming relativistic magnetohydrodynamic descriptions for the jets (astrophysical plasma outflows) and perform numerical simulations for neutrino, gamma-ray and secondary particle emissions. By adopting the existence of such jets in black hole microquasars (and also in AGNs), the spherical symmetry of emissions is no longer valid, i.e., it is broken, and the system needs to be studied accordingly. One of the main goals is to estimate particle collision rates and particle energy distributions inside the jet, from black-hole microquasars. As concrete examples, we choose the Galactic Cygnus X-1 and the extragalactic LMC X-1 systems.
In Situ Technological Innovation Diffusion Rate Accuracy Assessment
Authors: Parvin Albert Joseph , Beruvides Mario G. , Tercero-Gómez Víctor Gustavo
Published: February 2022

At present, the accuracy of diffusion rate forecasting, at a macro-level, in the research literature, is nonexistent. This research reveals underlying macro-level trends of diffusion rate assessment using historical technological innovation diffusion data to explore the statistical characteristics of diffusion rate percent-error of the Bass and logistic model time stepped through its lifecycle. A quantitative exploratory data analysis (EDA) based approach was employed to uncover underlying macro-perspective patterns and insights on a technological innovation’s forecasted diffusion rate percent-error using the data of 42 matured U.S. consumer technological innovations. An objective of this effort is to determine the statistical characteristics (mean, median, variance, standard deviation, skewness, and kurtosis) of diffusion rate assessment using the Bass and logistic model at various points in a technological innovation’s lifecycle to reveal underlying directional and associative insights. Specifically, this effort explores the development of macro-perspective knowledge on quantifying the forecasting accuracy of a technological innovation’s diffusion rate using partial diffusion data. Developing such insights and a framework for accessing in situ (real-time) a technological innovation’s diffusion rate percent-error would benefit an organization’s decision makers in maximizing gains and minimizing losses. These insights include identifying whether the Bass and logistic models are more likely to overestimate or underestimate a technological innovation’s diffusion rate when assessed at various points in its diffusion lifecycle. Practitioners can use such information to set resource investment strategies and policies based on risk tolerance and the utility of the weighted outcomes via decision theory tools.
Fumonisin B2 Induces Mitochondrial Stress and Mitophagy in Human Embryonic Kidney (Hek293) Cells—A Preliminary Study
Authors: Mohan Jivanka , Sheik Abdul Naeem , Nagiah Savania , Ghazi Terisha , Chuturgoon Anil A.
Published: February 2022

Ubiquitous soil fungi parasitise agricultural commodities and produce mycotoxins. Fumonisin B2 (FB2), the structural analogue of the commonly studied Fumonisin B1 (FB1), is a neglected mycotoxin produced by several Fusarium species. Mycotoxins are known for inducing toxicity via mitochondrial stress alluding to mitochondrial degradation (mitophagy). These processes involve inter-related pathways that are regulated by proteins related to SIRT3 and Nrf2. This study aimed to investigate mitochondrial stress responses in human kidney (Hek293) cells exposed to FB2 for 24 h. Cell viability was assessed via the methylthiazol tetrazolium (MTT) assay, and the half-maximal inhibitory concentration (IC50 = 317.4 µmol/L) was estimated using statistical software. Reactive oxygen species (ROS; H2DCFDA), mitochondrial membrane depolarisation (JC1-mitoscreen) and adenosine triphosphate (ATP; luminometry) levels were evaluated to assess mitochondrial integrity. The relative expression of mitochondrial stress response proteins (SIRT3, pNrf2, LONP1, PINK1, p62 and HSP60) was determined by Western blot. Transcript levels of SIRT3, PINK1 and miR-27b were assessed using quantitative PCR (qPCR). FB2 reduced ATP production (p = 0.0040), increased mitochondrial stress marker HSP60 (p = 0.0140) and suppressed upregulation of mitochondrial stress response proteins SIRT3 (p = 0.0026) and LONP1 (p = 0.5934). FB2 promoted mitophagy via upregulation of pNrf2 (p = 0.0008), PINK1 (p = 0.0014) and p62 (p < 0.0001) protein expression. FB2 also suppressed miR-27b expression (p < 0.0001), further promoting the occurrence of mitophagy. Overall, the findings suggest that FB2 increases mitochondrial stress and promotes mitophagy in Hek293 cells.
Antibodies against Anthrax Toxins: A Long Way from Benchlab to the Bedside
Authors: Avril Arnaud , Tournier Jean-Nicolas , Paucod Jean-Charles , Fournes Bénédicte , Thullier Philippe , Pelat Thibaut
Published: February 2022

Anthrax is an acute disease caused by the bacterium Bacillus anthracis, and is a potential biowarfare/bioterrorist agent. Its pulmonary form, caused by inhalation of the spores, is highly lethal and is mainly related to injury caused by the toxins secretion. Antibodies neutralizing the toxins of B. anthracis are regarded as promising therapeutic drugs, and two are already approved by the Federal Drug Administration. We developed a recombinant human-like humanized antibody, 35PA83 6.20, that binds the protective antigen and that neutralized anthrax toxins in-vivo in White New Zealand rabbits infected with the lethal 9602 strain by intranasal route. Considering these promising results, the preclinical and clinical phase one development was funded and a program was started. Unfortunately, after 5 years, the preclinical development was cancelled due to industrial and scientific issues. This shutdown underlined the difficulty particularly, but not only, for an academic laboratory to proceed to clinical development, despite the drug candidate being promising. Here, we review our strategy and some preliminary results, and we discuss the issues that led to the no-go decision of the pre-clinical development of 35PA83 6.20 mAb. Our review provides general information to the laboratories planning a (pre-)clinical development.
Cytotoxicity and Effects on the Synapsis Induced by Pure Cylindrospermopsin in an E17 Embryonic Murine Primary Neuronal Culture in a Concentration- and Time-Dependent Manner
Authors: Hinojosa María G. , Prieto Ana I. , Muñoz-Castro Clara , Sánchez-Mico María V. , Vitorica Javier , Cameán Ana M. , Jos Ángeles
Published: February 2022

Cylindrospermopsin (CYN) is a cyanotoxin whose incidence has been increasing in the last decades. Due to its capacity to exert damage at different levels of the organism, it is considered a cytotoxin. Although the main target organ is the liver, recent studies indicate that CYN has potential toxic effects on the nervous system, both in vitro and in vivo. Thus, the aim of the present work was to study the effects of this cyanotoxin on neuronal viability and synaptic integrity in murine primary cultures of neurons exposed to environmentally relevant concentrations (0–1 µg/mL CYN) for 12, 24, and 48 h. The results demonstrate a concentration- and time-dependent decrease in cell viability; no cytotoxicity was detected after exposure to the cyanotoxin for 12 h, while all of the concentrations assayed decreased this parameter after 48 h. Furthermore, CYN was also demonstrated to exert damage at the synaptic level in a murine primary neuronal culture in a concentration- and time-dependent manner. These data highlight the importance of studying the neurotoxic properties of this cyanotoxin in different experimental models.