bluuebunny/crossref_metadata_2025 huggingface dataset:
Analysis of Soil Carbon Stock Dynamics by Machine Learning—Polish Case Study
Authors: Łopatka Artur , Siebielec Grzegorz , Kaczyński Radosław , Stuczyński Tomasz
Published: August 2023

A simplified differential equation for the dynamics of soil organic carbon (SOC) that describes the rate of SOC change (dSOC/dt) was constructed using the LASSO regression—a regularized linear regression machine learning method. This method selects the best predefined explanatory variables and empirically evaluates the relevant parameters of the equation. The result, converted into a formula for the long-term equilibrium level of soil carbon, indicates the existence of carbon sequestration potential in the studied regions of Poland. In particular, the model predicts high SOC content in regions with a high Topographic Wetness Index (TWI), such as river valleys or areas with high cattle density, as expected.
Circulation Expectations, Farmer Trust, and Farmers’ Contract Choice Behavior
Authors: Wenjun Zhuo
Published: August 2023

This study investigates the influence of expectations and trust on farmers’ decisions regarding contractual choices in land transfer. The dataset used for analysis consists of 1101 households in a province in western China. The research focuses on two aspects: the selection between written and oral contracts, and the decision to continue the contractual relationship. The findings reveal that farmers’ choices are significantly affected by their expectations and levels of trust. Specifically, when farmers’ expectations regarding the land transfer process are not met, they tend to prefer written contracts over oral ones. This preference can be attributed to the greater clarity and risk reduction offered by written contracts. On the other hand, higher levels of trust increase the likelihood of farmers continuing the land transfer contract, as trust fosters a sense of confidence and security in the ongoing relationship. Interestingly, trust also plays a moderating role. Farmers who have aligned expectations and high levels of trust are more inclined to opt for oral contracts. This preference for oral contracts can be attributed to their flexibility and emphasis on interpersonal relationships, allowing for better adaptation to the changing dynamics of land transfer. These findings contribute to a deeper understanding of the factors influencing farmers’ decision-making processes regarding contractual choices in land transfer. They provide valuable insights for policymakers involved in land transfer, enabling them to optimize policies and facilitate farmers’ decision-making processes.
Empirical Investigation of Cultivated Land Green Use Efficiency and Influencing Factors in China, 2000–2020
Authors: Yang Bin , Wang Ying , Li Yan , Mo Lizi
Published: August 2023

The rapid industrialization and urbanization promote socioeconomic development, but also pose a certain threat to food and ecological security. Cultivated land green use efficiency (CLGUE) is an important indictor to comprehensively reflect the coordinated relationship between cultivated land utilization and ecological protection. Therefore, it is of great practical significance to explore CLGUE to guarantee efficient and sustainable utilization of cultivated land resources. This paper thus conducts an empirical investigation of 31 provinces in mainland China during 2000–2020, aiming to measure the CLGUE level using the Super-SBM model and explore its influencing factors based on panel regression model. The data, which were mainly derived from various statistical yearbooks, together with the reference dataset, were all accurate. The results show that the average CLGUE value in China exhibited a fluctuating upward development trend, with the highest efficiency value of 0.957 in 2020 and the lowest one of 0.853 in 2003. Northeastern China had the highest efficiency value, while Central China had the lowest efficiency value. The overall ranking of CLGUE in the four major regions from high to low is Northeastern, Eastern, Western, and Central China. Spatially, there are significant diversities in CLGUE across China, which means that differentiated measures need to be taken to improve the efficiency based on regional natural conditions and the socioeconomic level. The regression model indicated that the crop diversity index, GDP per capita, urbanization level, effective irrigation rate, and fiscal support for agriculture positively influenced the CLGUE, while the proportion of natural disaster area had a negative impact. The findings had important implications for improving the CLGUE and achieving sustainable agricultural development.
Research Advances in the Plant–Nematode Interaction
Authors: You Jia , Hu Yanfeng , Chen Jingsheng
Published: August 2023

Nematodes, which are highly important and abundant animals in the animal kingdom, demonstrate remarkable adaptability to various environments [...]
Lupenone-Rich Fraction Derived from Cissus quadrangularis L. Suppresses Lipid Accumulation in 3T3-L1 Adipocytes
Authors: Lakthan Thitiporn , Limpachayaporn Panupun , Rayanil Kanok-on , Charoenpanich Pornsri , Phuangbubpha Pornwipa , Charoenpanich Adisri
Published: August 2023

Cissus quadrangularis L. (CQ) has potential as a therapeutic for managing obesity and balancing metabolic activity, but the main bioactive compound and regulatory mechanism remain unknown. Herein, the CQ hexane extract was fractionated into 30 fractions (CQ-H) using flash column chromatography and analyzed using thin-layer chromatography. The direct antiadipogenesis effect of CQ-H fractions was tested on 3T3-L1 preadipocytes. Lupenone-rich fractions 2H and 3H were identified as containing potent antiadipogenesis agents that reduced differentiated cell numbers and intracellular lipid droplet size. Although the overall mitochondrial density remained unchanged, differentiated cells exhibited a higher mitochondrial density than that in non-differentiated cells. Additionally, 2H increased mitochondrial activity in both cell types as shown by their differentiation and lipid formation stages. Lupenone was isolated from 2H (Lu-CQ) and shown to dose-dependently inhibit adipogenesis, with 2H being more potent than Lu-CQ. Lu-CQ and 2H downregulated the expression of Pparg2 mRNA and upregulated that of glucose transporter genes, Slc2a1 and Slc2a4. Lu-CQ and 2H induced increased glucose uptake by 3T3-L1 cells. These findings suggest that lupenone-rich fractions in CQ contribute to balancing metabolic activity and reducing adipose tissue formation. Further exploration of CQ and its components may prompt innovative strategies for managing obesity and metabolic disorders.
A Review on Hypothesized Metabolic Pathways on Europa and Enceladus: Space-Flight Detection Considerations
Authors: Weber Jessica M. , Marlin Theresa C. , Prakash Medha , Teece Bronwyn L. , Dzurilla Katherine , Barge Laura M.
Published: August 2023

Enceladus and Europa, icy moons of Saturn and Jupiter, respectively, are believed to be habitable with liquid water oceans and therefore are of interest for future life detection missions and mission concepts. With the limited data from missions to these moons, many studies have sought to better constrain these conditions. With these constraints, researchers have, based on modeling and experimental studies, hypothesized a number of possible metabolisms that could exist on Europa and Enceladus if these worlds host life. The most often hypothesized metabolisms are methanogenesis for Enceladus and methane oxidation/sulfate reduction on Europa. Here, we outline, review, and compare the best estimated conditions of each moon’s ocean. We then discuss the hypothetical metabolisms that have been suggested to be present on these moons, based on laboratory studies and Earth analogs. We also detail different detection methods that could be used to detect these hypothetical metabolic reactions and make recommendations for future research and considerations for future missions.
Residual Feed Intake as an Efficiency Metric for Pre-Weaning Dairy Calves: What Do We Know?
Authors: Silva Camila S. da , Leão Juliana M. , Lage Camila F. A. , Coelho Sandra G. , Campos Mariana M.
Published: August 2023

Dairy cattle systems have targeted improvements in feed efficiency by selecting animals that can convert less feed into more products. Residual feed intake (RFI) has been the index of choice when selecting dairy cattle for feed efficiency. Nonetheless, RFI studies have focused on lactating cows, and the crucial importance of pre-weaning efficiency on farm profitability and cow productivity has been mostly neglected. This review discusses the current knowledge of how RFI divergence relates to nutrient metabolism in pre-weaning dairy calves, including the advantages and limitations of evaluating RFI in this phase. Existing literature indicates that nutrient utilization, energy metabolism, protein metabolism, vitamin metabolism, intestinal development, and hindgut bacterial populations may be implicated in RFI divergence between pre-weaning calves. Techniques developed to date to evaluate RFI in this phase are still evolving to better adapt to the unique characteristics of this phase, and more research is needed to fill in the gaps in our current understanding of early-life feed efficiency divergence in cattle. However, current results suggest great potential for selecting high-efficiency calves while in pre-weaning to accelerate the progress of genetic selection in dairy cattle.
Genetic Basis of Acinetobacter sp. K1 Adaptation Mechanisms to Extreme Environmental Conditions
Authors: Petrová Nikola , Kisková Jana , Kolesárová Mariana , Pristaš Peter
Published: August 2023

Anthropogenic pollution often leads to the generation of technosols, technogenic soils with inhospitable conditions for all living organisms including microbiota. Aluminum production near Ziar nad Hronom (Slovakia) resulted in the creation of a highly alkaline and heavy-metal-rich brown mud landfill, from which a bacterial strain of a likely new species of the genus Acinetobacter, Acinetobacter sp. K1, was isolated. The whole-genome sequence analysis of this strain confirmed the presence of operon units enabling tolerance to the heavy metals copper, zinc, cobalt, cadmium, chromium, and metalloid arsenic, which are functionally active. Despite the predominance of plasmid-related sequences in the K1 genome, the results indicate that most of the resistance genes are chromosomally encoded. No significant alkali tolerance of Acinetobacter sp. K1 was observed in vitro, suggesting that community level mechanisms are responsible for the survival of this strain in the highly alkaline, brown mud bacterial community.
Quercetin and Ferroptosis
Authors: Cruz-Gregorio Alfredo , Aranda-Rivera Ana Karina
Published: August 2023

Quercetin is a flavonoid present in apples, onions, tea, red wines, and berries, and it has shown different beneficial effects, such as providing cardiovascular protection, possessing anti-inflammatory properties, and demonstrating anticancer activity, among others. These diseases are related to oxidizing molecules such as ROS because these species react and induce the oxidation of cellular biomolecules, such as proteins, lipids, DNA, or carbohydrates, which alters cellular homeostasis. Regarding lipids, the oxidation of these molecules induces lipid hydroperoxides which, if not decreased, particularly by GPX4, produce highly reactive aldehydes such as 4HNE and MDA. These oxidative conditions induce ferroptosis, a type of cell death associated with oxidation that differs from other types of cell death, such as apoptosis, necrosis, or autophagy. The induction of ferroptosis is desired in some diseases, such as cancer, but in others, such as cardiovascular diseases, this type of cell death is not wanted. The possible effects of quercetin associated with reducing or inducing ferroptosis have not been reviewed. Thus, this review focuses on the ability of quercetin to produce ferroptosis in diseases such as cancer as a treatment option and, conversely, on its role in deactivating ferroptosis to alleviate diseases such as cardiovascular diseases.
Revisiting the Influence of Contact Length and Surrounding Medium on Metal Cutting Tribology
Authors: Ventura Carlos E. H. , Gregório Afonso V. L. , Fernandes Lara S. M. , Abrão Alexandre M. , Rosa Pedro A. R. C.
Published: August 2023

Metal cutting processes involve severe frictional conditions at the tool-chip contact interface, physico-chemical phenomena that are not fully understood and theoretical models with a strong empirical basis. In the literature, it is common to find values for the friction coefficient which are higher than the unit, despite the inconsistency of these findings with the mathematical theory of plasticity used for accurate modelling of the chip formation mechanics. Thus, the present work seeks to contribute to a better understanding of metal cutting tribology based on well-controlled and specially designed experimental conditions. To enable the stress state at the contact interface to be determined and to provide a known real contact area, polished cutting inserts with prepared rake faces were used to restrict the contact length in orthogonal cutting tests under controlled atmospheres. These conditions also allowed the contribution of the sticking mechanisms to be minimized. Cutting tools of restricted contact lengths have been found to reduce process forces and the friction coefficient, while industrial standard inserts make cutting operation sensitive to the chemical composition of the surrounding atmosphere.
Dynamic Temperature Prediction on High-Speed Angular Contact Ball Bearings of Machine Tool Spindles Based on CNN and Informer
Authors: Li Hongyu , Liu Chunyang , Yang Fang , Ma Xiqiang , Guo Nan , Sui Xin , Wang Xiao
Published: August 2023

This study addressed the issues related to the difficulty of determining the operating status of machine tool spindle bearings due to the high rotational speeds and rapid temperature fluctuations. This paper presents an optimized model that combines Convolutional Neural Networks (CNNs) and Informer to dynamically predict the temperature rise process of bearings. Taking the H7006C angular contact ball bearing as the research object, a combination of experimental data and simulations was used to obtain the training dataset. Next, a model for predicting the temperature rise of the bearing was constructed using CNN + Informer and the structural parameters were optimized. Finally, the model’s generalization ability was then verified by predicting the bearing temperature rise process under various working conditions. The results show that the error of the simulation data source model was less than 1 °C at steady state; the temperature error of the bearing temperature rise prediction model was less than 0.5 °C at both the temperature rise and steady-state stages under variable rotational speeds and variable load conditions compared to Informer and Long Short Term Memory (LSTM) models; the maximum prediction error of the operating conditions outside the dataset was less than 0.5 °C, and the temperature rise prediction model has a high accuracy, robustness, and generalization capability.
A Multi-Scale Investigation to Predict the Dynamic Instabilities Induced by Frictional Contact
Authors: Maaboudallah Farouk , Atalla Noureddine
Published: August 2023

We propose a new variational formulation to model and predict friction-induced vibrations. The multi-scale computational framework exploits the results of (i) the roughness measurements and (ii) the micro-scale contact simulations, using the boundary element method, to enrich the contact zone of the macroscopic finite element model of rubbing systems with nominally flat contact boundaries. The resulting finite elements at the contact interface of the macroscopic model include (i) a modified normal gap and (ii) a micro-scale description of the contact law (i.e., pressure gap) derived by solving the frictionless contact problem on a rough surface indenting a rigid half-plane. The method is applied to a disc brake system to show its robustness in comparison with classical deterministic formulations. With respect to the traditional complex eigenvalues analysis, the proposed multi-scale approach shows that the inclusion of roughness significantly improves the results at low frequencies. In this panorama, any improvement of dynamic instabilities predictions should be based on an uncertainty analysis incorporating roughness combined with other parameters such as friction coefficient and shear moduli of the pads, rather than on roughness itself.
Experimental and Numerical Investigation of the Tensile and Failure Response of Multiple-Hole-Fiber-Reinforced Magnesium Alloy Laminates under Various Temperature Environments
Authors: Lin Zhongzhao , Sheng Dongfa , Fang Yuting , Xiong Ke , Song Yuming
Published: August 2023

In this paper, the tensile mechanical behavior and progressive damage morphology of glass-fiber-reinforced magnesium alloy laminate for different numbers of holes in a temperature range of 25–180 °C were investigated. In addition, based on extensive tensile tests, the tensile mechanical behavior and microscopic damage morphology of porous-glass-fiber-reinforced magnesium alloy laminates at different temperatures were observed by finite element simulation and scanning electron microscopy (SEM). Finally, the numerical simulation and experimental results were in good accordance with the prediction of mechanical properties and fracture damage patterns of the laminates, the average difference between the residual strength values of the specimens at ambient temperature was 5.57%, and the stress–strain curves were in good agreement. The experimental and finite element analysis results showed that the damaged area of the bonded layer tended to expand with the increase in the number of holes, which has a lesser effect on the ultimate tensile strength. As the temperature increased, the specimens changed from obvious fiber breakage (pull-out) and the resin matrix damage mode to matrix softening damage and interfacial delamination fracture damage. As the testing temperature of the specimens increased from 25 °C to 180 °C, the tensile strength of the specimens decreased by an average of 51.59%, while the tensile strength of the specimens showed a nonlinear decreasing trend. The damage mechanism of porous-glass-fiber-reinforced magnesium alloy laminates at different temperatures is discussed in this paper, which can provide a reference for engineering applications and design.
Controlling the Cooling Rate of Hydrothermal Synthesis to Enhance the Supercapacitive Properties of β-Nickel Hydroxide Electrode Materials
Authors: Lu Yang-Ming , Hong Sheng-Huai
Published: August 2023

The demand for power storage devices with good quality, fast charging and high energy density is becoming more and more urgent in today’s electronic technology. For batteries and traditional capacitors, it is an insurmountable challenge to combine fast charging and discharging, large capacitance and long-life properties. The characteristics of supercapacitors can meet all the above requirements at the same time. In this study, a simple one-step hydrothermal method was successfully used to grow β-nickel hydroxide nanocone particles directly on the 3D foamed nickel substrate as a working electrode material for supercapacitors. After growing β-nickel hydroxide crystals on 3D foamed nickel substrate, by controlling the cooling rate, a well-crystalized β-nickel hydroxide with good capacitance characteristics can be obtained. Cyclic voltammetry (CV), galvanostatic charge–discharge (GCD) and electrochemical impedance spectroscopy (EIS) were used to analyze the capacitance characteristics of the β-nickel hydroxide electrode. The research results show that the specific capacitance value of the β-Ni(OH)2/3D nickel foam electrode material prepared at the cooling rate of 10 °C/h can reach 539 F/g with the charge–discharge test at a current density of 3 A/g. After 1000 continuous charge and discharge cycles, the material still retains 94.1% of the specific capacitance value.
Recent Advances on Porous Siliceous Materials Derived from Waste
Authors: Montini Daniele , Cara Claudio , D’Arienzo Massimiliano , Di Credico Barbara , Mostoni Silvia , Nisticò Roberto , Pala Luca , Scotti Roberto
Published: August 2023

In recent years, significant efforts have been made in view of a transition from a linear to a circular economy, where the value of products, materials, resources, and waste is maintained as long as possible in the economy. The re-utilization of industrial and agricultural waste into value-added products, such as nanostructured siliceous materials, has become a challenging topic as an effective strategy in waste management and a sustainable model aimed to limit the use of landfill, conserve natural resources, and reduce the use of harmful substances. In light of these considerations, nanoporous silica has attracted attention in various applications owing to the tunable pore dimensions, high specific surface areas, tailorable structure, and facile post-functionalization. In this review, recent progress on the synthesis of siliceous materials from different types of waste is presented, analyzing the factors influencing the size and morphology of the final product, alongside different synthetic methods used to impart specific porosity. Applications in the fields of wastewater/gas treatment and catalysis are discussed, focusing on process feasibility in large-scale productions.
The Numerical and Experimental Investigation of Piezoresistive Performance of Carbon Nanotube/Carbon Black/Polyvinylidene Fluoride Composite
Authors: Huang Kaiyan , Tong Shuying , Shi Xuewei , Wen Jie , Bi Xiaoyang , Li Alamusi , Zou Rui , Kong Wei , Yin Hui , Hu Wei , Zhao Libin , Hu Ning
Published: August 2023

The composites with multiple types of nano-carbon fillers have better electrical conductivity and piezoresistive properties as compared with composites with a single type of nano-carbon fillers. As previously reported, the nano-carbon fillers with various aspect ratios, such as carbon nanotube (CNT) and carbon black (CB), have synergistic enhanced effects on the piezoresistive performance of composite sensors. However, most of the works that have been reported are experimental investigations. The efficient and usable numerical simulation investigation needs to be further developed. In this study, based on an integrated 3D statistical resistor network model, a numerical simulation model was created to calculate the piezoresistive behavior of the CNT/CB/ Polyvinylidene Fluoride (PVDF) composite. This model also takes into account the tunneling effect between nearby nano-fillers. It is found from numerical simulation results that the piezoresistive sensitivity of composite simulation cells can be influenced by the fraction of CNT and CB. In the case that the CNT content is 0.073 wt.%, the best force-electrical piezoresistive sensitivity can be achieved when the CB loading is up to 0.2 wt.%. To verify the validity of the simulation model, the previous experimental investigation results are also compared. The experimental results confirm the validity of the model. The investigation is valuable and can be utilized to design a strain sensor for this nano-composite with increased sensitivity.
In Situ Characterization of 17-4PH Stainless Steel by Small-Angle Neutron Scattering
Authors: Yan Shibo , Wang Zijun , Li Tianfu , Chen Zhong , Du Xiaoming , Liu Yuntao , Chen Dongfeng , Sun Kai , Liu Rongdeng , Bai Bing , He Xinfu , Liu Kaitai , Wang Shuanzhu
Published: August 2023

17-4PH martensitic steel is usually used as valve stems in nuclear power plants and it suffers from thermal aging embrittlement due to long-time service in a high-temperature and high-pressure environment. Here, we characterized the evolution of microstructures at the nano-scale in 17-4PH steel by in situ small-angle neutron scattering (SANS) with a thermo-mechanically coupled loading device. The device could set different temperatures and tensile so that an in situ SANS experiment could dynamically characterize the process of nanoscale structural changes. The results showed that with increasing thermal aging time, the ε-Cu phase precipitates and grows as the temperature is 475 °C and 590 °C, and the ε-Cu phase is spherical at 475 °C but became elongated cylinders at 590 °C. Moreover, the loading stress could aid in the growth of the ε-Cu phase at 475 °C.
Creep of Concrete in Shell Structures: Nonlinear Theory
Authors: Mussabayev Turlybek Turkpenovich , Nuguzhinov Zhmagul Smagulovich , Nemova Darya , Kayupov Tabyldy , Tolkynbaev Temirkhan Anapiyaevich , Akmakanova Assel Zhanalykovna , Khafizova Gulzhan Sailaubekovna
Published: August 2023

The creep of concrete is one of the main problems threatening concrete structural development and the stability and safety of structures. However, the nonlinear theory is the key to solving the problem of taking into account the physical and mechanical properties of concrete creep in shell structures. To create such a theory, the original shell is replaced by a continuous equivalent elastic shell. To determine the stress–strain state of the structure, the equations of nonlinear creep and crack growth are derived, and a deformation model of the section is created. The behavior of the structure at all stages of the life cycle is investigated by solving the solving systems of differential equations of equilibrium, motion, and perturbation of the equivalent shell. The values of the ratios of dependence of long-term and short-term critical loads on deformations, forces, cracks, etc., are given. The accuracy of the solution of the developed nonlinear theory is compared with the linear theory of concrete creep as well as experimental data. The results show that, according to the linear theory, for the values for the short term and long term, up to 56% and up to 39% of critical loads are overestimated, respectively. The creep process in practical engineering can be effectively controlled by the results of the proposed theory.
The Effect of CoAl2O4 as a Nucleating Agent and Pouring Temperature on the Microstructure and Properties of Inconel 713C® Nickel-Based Superalloy Castings
Authors: Cygan Rafał , Rakoczy Łukasz
Published: August 2023

In this work, three melt-pouring temperatures (1450 °C, 1480 °C, 1520 °C) and CoAl2O4 inoculant contents in the shell mold’s primary coating (0 wt%, 5 wt%, and 10 wt%) were selected to study microstructural and mechanical property changes of the Inconel 713C® nickel-based superalloy. The castings’ phase transformation temperatures, phase constitution, microstructure, and mechanical properties at room and elevated temperatures were investigated via thermodynamical simulations, differential thermal analysis, light and scanning electron microscopy, energy-dispersive X-ray spectroscopy, and tensile and stress-rupture tests. The pouring temperature and inoculant content strongly influenced the mean equiaxed grain size, which ranged between 2.36 and 6.55 mm. The primary microstructure of Inconel 713C® castings, owing to its complex chemical composition, comprised multiple phases, including γ, γ’, MC, M3B2, and Ni7Zr2. The mean size of γ’ was in the 0.446–0.613 μm range, depending on the casting variant. Grain refinement with CoAl2O4 at ambient temperature for each melt-pouring temperature led to increased yield strength (YS) and ultimate tensile strength (UTS). YS was in the range of 775–835 MPa, while UTS was in the range of 868–1010 MPa. A reverse trend was observed in samples that crept in 982 °C/152 MPa, while for each variant, the time to rupture exceeded 30 h. The maximum time to rupture was 46.1 h obtained in the unmodified casting poured at 1480 °C.
A Compact Three-Dimensional Two-Layer Flexible Hinge
Authors: Lobontiu Nicolae , Moses Morgan , Hunter Jozef , Min Daniel , Munteanu Mircea Gh.
Published: August 2023

The paper proposes a new three-dimensional flexible hinge formed of several serially linked straight- and circular-axis segments that are disposed of in two layers. The novel hinge configuration is capable of large displacements and can be implemented in precision-compliant mechanisms that need to cover large spatial workspaces. Based on simplified geometry, an analytical compliance model is formulated that connects the loads to the displacements at one end of the hinge. Finite element simulation and experimental prototype testing of actual-geometry hinge configurations confirm the analytical model predictions. A related compliance-based analytical model evaluates the maximum loads that can be applied to the hinge and the resulting displacements. The two small-deformation analytical models are subsequently utilized to investigate the relationship between geometric parameters and the hinge performance qualifiers.
Triboelectric Film Sensor for Integrity Monitoring of Bolted Joints
Authors: Wang Chu , Miura Nanako , Masuda Arata
Published: August 2023

In this study, a concept and design of a self-powered sensor that utilizes a triboelectric effect to evaluate the condition of tensile bolted joints was proposed. Based on the fact that the triboelectric charge yields electrostatic voltage induced by the separation of the contacting rough surfaces, the proposed sensor is a film-shaped triboelectric sensor made of inexpensive materials being installed between the objects to be fastened. The principle of the sensor is that it detects microscale relative motions between the contacting surfaces against an external vibratory load when the integrity of the fastened joint is compromised due to a decrease in the bolt’s fastening force. In this study, we designed and fabricated triboelectric sensor and tested it on a tensile bolted joint specimen subjected to inertial vibratory loading, and it was experimentally shown that the output voltage amplitude of the sensor increased as the bolt’s fastening force decreased. In addition, a modeling study was performed to explain the unexpected decrease in voltage amplitude observed at medium preloads, by combining the triboelectric and mechanical models with the experimental results of two different external circuit configurations. Estimation of the triboelectric charge density at the contacting surfaces was performed, which was found to be consistent with the contact mechanics model assumed. Finally, the calculation of the sensor output voltage based on the presented mechanical/triboelectric model was provided, confirming the validity of the modeling study.
Enhancing the Performance of a Simulated WWTP: Comparative Analysis of Control Strategies for the BSM2 Model
Authors: Roșu Bogdan , Mocanu George Dănuț , Pila Mihaela Munteanu , Murariu Gabriel , Roșu Adrian , Arseni Maxim
Published: August 2023

This study aimed to improve the performance of a wastewater treatment plant (WWTP) simulated with Benchmark Model No. 2 (BSM2). To achieve this objective, three control strategies were implemented and tested. The first control strategy aimed to maintain the concentration of nitrate and nitrite nitrogen (SNO) by controlling the external carbon flowrate (strategy A1), and the second control strategy aimed to maintain the ammonia and ammonium nitrogen (SNH) at a desired level with the use of a cascade controller (strategy A2). The third strategy was applied to control the total suspended solids (TSS) (strategy A3). Combinations of these strategies were considered (B1, B2, and B3 strategies), as well as the use of all three together (strategy C1). The control strategies presented in this paper were compared to the default control strategy of BSM2 to validate and identify the one that provided the best performance. The results revealed that the B1 strategy was the most environmentally friendly, while C1 obtained the highest overall performance. Several Monte Carlo simulations were performed for the validated control strategies, to identify the optimal setpoint values. For the C1 strategy, a second method of optimization regarding polynomial interpolation was considered. The applied optimization methods provided the optimal reference values for the PI (proportional integral) controllers.
A Blockchain-Based Continuous Micropayment Scheme Using Lockable Signature
Authors: Wang Wennan , Chen Guoxin , Chu Chiawei , Lan Wusong
Published: August 2023

A blockchain-oriented continuous micropayment system forms an integral element of the digital economy, enabling seamless transactions and encouraging minor purchases. However, due to the inherent throughput constraints of blockchain, payment channels (PCs) are customarily deployed for managing high-volume transactions in an off-chain mode. Despite this, the integration of a PC necessitates a trusted intermediary to safeguard transactional security, thereby imposing an extra security assumption as only the initial and concluding transactions are visible to other system participants. To circumvent this limitation, we introduce an innovative micropayment structure utilizing lockable signatures. Each transaction within the PC coalesces into a continuous microtransaction hash-chain (CMHC), precluding unscrupulous users from accessing transactional data during the process. Additionally, all locks within the CMHC remain concealed throughout the transaction, with all information relayed in a tamper-proof manner. We provide a comprehensive security analysis and perform a gamut of evaluations. Empirical evidence indicates that our proposed system outperforms existing state-of-the-art solutions in transaction time and verification expenses. This lockable signature-dependent micropayment system not only ensures robust security but also enhances transactional speed and efficiency, thereby catalyzing the growth of the digital economy.
Research and Development of an Industrial Denitration-Used Burner with Multiple Ejectors via Computational Fluid Dynamics Analysis
Authors: Tong Chengguang , Chen Zuobing , Chen Xin , Xie Qiang
Published: August 2023

Nowadays, since the air pollution problem is becoming global and denitrification is efficient to control nitrogen oxides, research and development of burners with low pollutant emissions in industries are urgent and necessary due to the increasingly severe environmental requirements. Based on the advanced CFD (computational fluid dynamics) numerical analysis technique, this work focuses on developing an industrial denitration-used burner, aiming to decrease the emission of nitrogen oxides. A burner with multiple ejectors is proposed, and the gas premixing and combustion process in the burner are systematically studied. Firstly, for the ejector, the well-known orthogonal experiment method is adopted to reveal the premixing performance under different structural parameters. Results show that the angle and number of swirl blades have significant effects on the CO mixing uniformity. The CO mixing uniformity first decreases and then increases with thr rising swirl blade angle, and it enhances with more swirl blades. Through comparison, a preferred ejector is determined with optimal structure parameters including the nozzle diameter of 75 mm, the ejector suction chamber diameter of 290 mm, the blade swirl angle of 45∘, and the swirl blade number 16. And then, the burners installed with the confirmed ejector and two types of flues, i.e., a cylindrical and a rectangular one, are simulated and compared. The effects of ejector arrangements on the temperature distributions at the burner outlet are analyzed qualitatively and quantitatively. It is found that the temperature variances at the outlets of R2 and C1 are the smallest, respectively, 13.12 and 23.69, representing the optimal temperature uniformity under each type. Finally, the burner of the R2 arrangement is verified with a satisfied premixing performance and combustion temperature uniformity, meeting the denitration demands in the industry.
Privacy Preservation Using Machine Learning in the Internet of Things
Authors: El-Gendy Sherif , Elsayed Mahmoud Said , Jurcut Anca , Azer Marianne A.
Published: August 2023

The internet of things (IoT) has prepared the way for a highly linked world, in which everything is interconnected, and information exchange has become more easily accessible via the internet, making it feasible for various applications that enrich the quality of human life. Despite such a potential vision, users’ privacy on these IoT devices is a significant concern. IoT devices are subject to threats from hackers and malware due to the explosive expansion of IoT and its use in commerce and critical infrastructures. Malware poses a severe danger to the availability and reliability of IoT devices. If left uncontrolled, it can have profound implications, as IoT devices and smart services can collect personally identifiable information (PII) without the user’s knowledge or consent. These devices often transfer their data into the cloud, where they are stored and processed to provide the end users with specific services. However, many IoT devices do not meet the same security criteria as non-IoT devices; most used schemes do not provide privacy and anonymity to legitimate users. Because there are so many IoT devices, so much malware is produced every day, and IoT nodes have so little CPU power, so antivirus cannot shield these networks from infection. Because of this, establishing a secure and private environment can greatly benefit from having a system for detecting malware in IoT devices. In this paper, we will analyze studies that have used ML as an approach to solve IoT privacy challenges, and also investigate the advantages and drawbacks of leveraging data in ML-based IoT privacy approaches. Our focus is on using ML models for detecting malware in IoT devices, specifically spyware, ransomware, and Trojan horse malware. We propose using ML techniques as a solution for privacy attack detection and test pattern generation in the IoT. The ML model can be trained to predict behavioral architecture. We discuss our experiments and evaluation using the “MalMemAnalysis” datasets, which focus on simulating real-world privacy-related obfuscated malware. We simulate several ML algorithms to prove their capabilities in detecting malicious attacks against privacy. The experimental analysis showcases the high accuracy and effectiveness of the proposed approach in detecting obfuscated and concealed malware, outperforming state-of-the-art methods by 99.50%, and would be helpful in safeguarding an IoT network from malware. Experimental analysis and results are provided in detail.
Oscillation Analysis Algorithm for Nonlinear Second-Order Neutral Differential Equations
Authors: Song Liang , Chen Shaodong , Wang Guoxin
Published: August 2023

Differential equations are useful mathematical tools for solving complex problems. Differential equations include ordinary and partial differential equations. Nonlinear equations can express the nonlinear relationship between dependent and independent variables. The nonlinear second-order neutral differential equations studied in this paper are a class of quadratic differentiable equations that include delay terms. According to the t-value interval in the differential equation function, a basis is needed for selecting the initial values of the differential equations. The initial value of the differential equation is calculated with the initial value calculation formula, and the existence of the solution of the nonlinear second-order neutral differential equation is determined using the condensation mapping fixed-point theorem. Thus, the oscillation analysis of nonlinear differential equations is realized. The experimental results indicate that the nonlinear neutral differential equation can analyze the oscillation behavior of the circuit in the Colpitts oscillator by constructing a solution equation for the oscillation frequency and optimizing the circuit design. It provides a more accurate control for practical applications.
Uniform {Ch,S(Ch)}-Factorizations of Kn−I for Even h
Authors: Lo Faro Giovanni , Milici Salvatore , Tripodi Antoinette
Published: August 2023

Let H be a connected subgraph of a graph G. An H-factor of G is a spanning subgraph of G whose components are isomorphic to H. Given a set H of mutually non-isomorphic graphs, a uniform H-factorization of G is a partition of the edges of G into H-factors for some H∈H. In this article, we give a complete solution to the existence problem of uniform H-factorizations of Kn−I (the graph obtained by removing a 1-factor from the complete graph Kn) for H={Ch,S(Ch)}, where Ch is a cycle of length an even integer h≥4 and S(Ch) is the graph consisting of the cycle Ch with a pendant edge attached to each vertex.
Hidden Markov Model-Based Control for Cooperative Output Regulation of Heterogeneous Multi-Agent Systems under Switching Network Topology
Authors: Hong Gia-Bao , Kim Sung-Hyun
Published: August 2023

This paper investigates the problem of stochastically cooperative output regulation of heterogeneous multi-agent systems (MASs) subject to hidden Markov jumps using observer-based distributed control. In order to address a more realistic situation than prior studies, this paper focuses on the following issues: (1) asynchronous phenomena in the system mode’s transmission to the controller; (2) the impact of system mode switching on network topology; and (3) the emergence of coupled terms between the mode-dependent Lyapunov matrix and the control gain in control design conditions. Specifically, to reduce the complexity arising from the asynchronous controller-side mode, the leader–state observer is developed so that the solution pair of regulator equations can be integrated into the observer. Furthermore, a linear decoupling method is proposed to handle the emergence of the aforementioned coupled terms; this provides sufficient LMI conditions to achieve stochastically cooperative output regulation for heterogeneous MASs. Finally, the validity of the proposed method is shown through two illustrative examples.
Effect of Weight Thresholding on the Robustness of Real-World Complex Networks to Central Node Attacks
Authors: John Jisha Mariyam , Bellingeri Michele , Lekha Divya Sindhu , Cassi Davide , Alfieri Roberto
Published: August 2023

In this study, we investigate the effect of weight thresholding (WT) on the robustness of real-world complex networks. Here, we assess the robustness of networks after WT against various node attack strategies. We perform WT by removing a fixed fraction of weak links. The size of the largest connected component indicates the network’s robustness. We find that real-world networks subjected to WT hold a robust connectivity structure to node attack even for higher WT values. In addition, we analyze the change in the top 30% of central nodes with WT and find a positive correlation in the ranking of central nodes for weighted node centralities. Differently, binary node centralities show a lower correlation when networks are subjected to WT. This result indicates that weighted node centralities are more stable indicators of node importance in real-world networks subjected to link sparsification.
Petrosamine Revisited. Experimental and Computational Investigation of Solvatochromism, Tautomerism and Free Energy Landscapes of a Pyridoacridinium Quaternary Salt
Authors: Gartshore Christopher J. , Wang Xiao , Su Yongxuan , Molinski Tadeusz F.
Published: August 2023

Petrosamine (1)—a colored pyridoacridine alkaloid from the Belizean sponge, Petrosia sp., that is also a potent inhibitor of acetylcholine esterase (AChE)—was investigated by spectroscopic and computational methods. Analysis of the petrosamine-free energy landscapes, pKa and tautomerism, revealed an accurate electronic depiction of the molecular structure of 1 as the di-keto form, with a net charge of q = +1, rather than a dication (q = +2) under ambient conditions of isolation-purification. The pronounced solvatochromism (UV-vis) reported for 1, and related analogs were investigated in detail and is best explained by charge delocalization and stabilization of the ground state (HOMO) of 1 rather than an equilibrium of competing tautomers. Refinement of the molecular structure 1 by QM methods complements published computational docking studies to define the contact points in the enzyme active site that may improve the design of new AChE inhibitors based on the pyridoacridine alkaloid molecular skeleton.
Diagnostic and Prognostic Roles of GATA3 Immunohistochemistry in Urothelial Carcinoma
Authors: Yoo Daeseon , Min Kyueng-Whan , Pyo Jung-Soo , Kim Nae Yu
Published: August 2023

This study aimed to evaluate the diagnostic and prognostic roles of GATA-binding protein 3 (GATA3) immunohistochemistry in urothelial carcinoma (UC) using a meta-analysis. We investigated GATA3 immunohistochemical expression rates and performed a subgroup analysis based on tumor site, study location, and histological subtypes. The overall survival rates of patients with GATA3-positive and -negative UC were compared. The estimated GATA3 expression rate was 0.748 (95% confidence interval [CI]: 0.704–0.787). GATA3 expression rates in the urinary bladder and urinary tract were 0.775 (95% CI: 0.727–0.818) and 0.614 (95% CI: 0.426–0.774), respectively. The GATA3 expression rates of noninvasive and invasive UCs were 0.965 (95% CI: 0.938–0.980) and 0.644 (95% CI: 0.581–0.702), respectively. In invasive UCs, there was a significant difference in GATA3 expression between non-muscular invasion and muscular invasion subgroups (0.937, 95% CI: 0.883–0.967 vs. 0.753, 95% CI: 0.645–0.836). GATA3 expression was the highest in the microcytic subtype among the histologic subtypes (0.952, 95% CI: 0.724–0.993). There was a significant correlation between GATA3 expression and better prognosis (hazard ratio: 0.402, 95% CI: 0.311–0.521). Taken together, GATA3 expression significantly correlated with low-stage and better prognosis in UC. GATA3 expression is highly variable across histological subtypes, and one should be careful while interpreting GATA3 expression.
Intermittent Fasting and Reduction of Inflammatory Response in a Patient with Ulcerative Colitis
Authors: Roco-Videla Ángel , Villota-Arcos Claudio , Pino-Astorga Carolina , Mendoza-Puga Daniela , Bittner-Ortega Mauricio , Corbeaux-Ascui Tatiana
Published: August 2023

Ulcerative colitis is an inflammatory disease that affects the colon, generating a crisis period associated with diarrhea and ulcerations. Stress plays a pivotal role in modulating the inflammatory response and aggravating progression. Different studies have shown that fasting reduces inflammation markers, and intermittent fasting decreases inflammatory markers such as IL-2, IL-6, and RCP. Goal: To evaluate the impact of intermittent fasting on a patient diagnosed with ulcerative colitis. A female patient underwent intermittent fasting (10/14) for eight weeks. Clinical tests were performed for blood count, RCP, biochemical profile, glycemia, and T4/TSH levels. Fecal calprotectin was determined. Clinical exams were assessed before and after intermittent fasting. Inflammation markers, such as CRP and calprotectin, were significantly reduced after eight weeks of intermittent fasting. The patient reported feeling better and was seizure-free during the following months when she continued fasting intermittently. Intermittent fasting allowed for a reduction in inflammation markers.