bluuebunny/crossref_metadata_2025 huggingface dataset:
Comfort-Oriented Semi-Active Suspension Configuration with Inerter-Based Network Synthesis
Authors: Li Yalin , Han Shichang , Xiong Junlin , Wang Wenbo
Published: July 2023

This paper presents a comfort-oriented semi-active suspension system composed of a network-synthesized passive section and a controllable section based on a semi-active inerter. Firstly, the semi-active suspension system is divided into a passive part and a controllable part. For the passive part, first-order and second-order robust positive real controllers are designed. The problem with H2 cost is considered, and the bilinear matrix inequalities (BMI) are solved using an iterative method to obtain two admittance functions. The admittance functions are physically realized as two mechanical networks composed of mechanical passive elements such as inerter, spring, and damper (ISD). Then, the parameters of these mechanical elements in those networks are optimized by Particle Swarm Optimization (PSO). Secondly, a semi-active inerter based on Sky-hook control is introduced for the semi-active part of the suspension system. Finally, the semi-active ISD suspension structure is verified by a quarter vehicle model. The simulation results show that the first-order and second-order suspension systems optimize the RMS of the spring mass acceleration by 14.2% and 23.9%, respectively, as compared to traditional suspension systems. Furthermore, frequency-domain analysis also shows that both suspension systems effectively reduce the value of spring mass acceleration in the low-frequency band.
Airfoil Analysis and Optimization Using a Petrov–Galerkin Finite Element and Machine Learning
Authors: Areias Pedro , Correia Rodrigo , Melicio Rui
Published: July 2023

For the analysis of low-speed incompressible fluid dynamics with turbulence around airfoils, we developed a finite element formulation based on a stabilized pressure and velocity formulation. To shape the optimization of bidimensional airfoils, this formulation is applied using machine learning (TensorFlow) and public domain global optimization algorithms. The goal is to maximize the lift-over-drag ratio by using the class-shape function transformation (CST) parameterization technique and machine learning. Specifically, we propose equal-order stabilized three-node triangles for the flow problem, standard three-node triangles for the approximate distance function (ADF) required in the turbulence stage, and stabilized three-node triangles for the Spalart–Allmaras turbulence model. The backward Euler time integration was employed. An implicit time-integration algorithm was adopted, and a solution was obtained using the Newton–Raphson method. This was made possible in the symbolic form via Mathematica with the AceGen package. Three benchmarks are presented, with Reynolds numbers up to 1×107, demonstrating remarkable robustness. After the assessment of the new finite element, we used machine learning and global optimization for four angles of attack to calculate airfoil designs that maximized CL/CD.
High-Precision Magnetic Testbed Design and Simulation for LEO Small-Satellite Control Test
Authors: Uscategui Jhonny , Wang Xinsheng , Cuba Gerson , Guarirapa María
Published: July 2023

Small satellites with academic missions in low Earth orbit (LEO) employ magnetic attitude control systems primarily due to their ease of development and low cost. These systems utilize magnetorquers to generate a magnetic moment that interacts with Earth’s magnetic field, enabling controlled rotation of the satellite around its three axes. The successful execution of these satellite missions relies heavily on rigorous magnetic testing conducted on the Attitude Determination and Control (ADC) subsystem. Hence, the design of a magnetic field simulator that enables precise testing is of utmost importance. This paper presents a comprehensive study, analysis, and verification of the construction of a magnetic testbed capable of accurately reproducing terrestrial magnetic fields in low Earth orbits. The research was conducted in four stages. Firstly, Matlab/Simulink software was employed to predict the satellite’s orbit and the corresponding Earth’s magnetic field affecting it. Secondly, the three-axis magnetic testbed was simulated using Ansys Maxwell software to validate its technical characteristics. In the third stage, based on the previous data, the testbed was assembled and integrated into a university laboratory. Finally, calibration, testing, and verification of the testbed’s results were performed while reproducing Earth’s magnetic field from the satellite’s orbit. The final outcome was a flexible testbed design with the results exhibiting a precision exceeding 99.89%. This confirms that the magnetic testbed reliably generates results during small-satellite magnetic control tests.
The State of Grain Trade between China and Russia: Analysis of Growth Effect and Its Influencing Factors
Authors: Fu Jing , Tong Guangji
Published: July 2023

As two influential countries in the global grain production and marketing system, China and Russia have increasingly strengthened their agricultural, economic, and trade cooperation. There are few papers that have considered trade relations from the perspective of the growth effect of grain exports, and it is necessary to fill this gap by systematically sorting the grain trade between the two countries and clarifying the growth effect and influencing factors in this paper. By comparing and analyzing the quantitative and structural characteristics of grain trade between China and Russia between 1996 and 2020, this study used the H–K marginal analysis method to explore the growth path and influencing factors of the export trade of grain products between China and Russia. The results show that the main driving force of the export growth of Russian and Chinese grain products is the price margin, which presents a growth pattern dominated by price and complemented by type and quantity. The empirical analysis of the gravity model shows that the size of the agricultural economy, grain productivity, trade cost, and economic shocks have significant impacts on bilateral trade. In view of this, the status of international agricultural cooperation between China and Russia will be further optimized if they can optimize trade policies to improve the quality of trade development, build cross-border cooperation parks to construct the layout of the whole industrial chain, strengthen infrastructure construction, and deepen and expand interconnectivity.
Morphology, Behaviour and Evolution of Gallotia Lizards from the Canary Islands
Authors: Molina-Borja Miguel , Bohórquez-Alonso Martha L.
Published: July 2023

We summarize, here, the results from several studies conducted over many years on several endemic species of lizards (genus Gallotia) from the Canary Islands. Quantitative analyses show clear differences both among the species of every island and populations within each species. Sexual dimorphism exists in all analysed species, and a phylogenetic analysis shows that the degree of dimorphism did not change along the evolutionary history of the Canary Islands: species with large and small body sizes have a similar degree of sexual dimorphism, with male body size changes closely following those undergone by females. In G. caesaris (from El Hierro and La Gomera islands) and in G. stehlini (from Gran Canaria), longer hind limb length was correlated with more open habitats. Within most species, males are more conspicuous than females, mainly in terms of body size, behaviour and coloration pattern. Lateral colour spots are blue in most species and green in others. In G. galloti from Tenerife, male lateral spots have larger spot areas and percentage of reflectance in the ultraviolet/blue part of the spectrum than females. This trait shows a monthly variation along April to July, both in males and females, its magnitude being larger in May–June. Behaviour analysis, especially in the last species, shows a great diversity in behaviour patterns, and analysis of intrasexual male competition revealed that contest outcome depends on several morphological and colouration characteristics but mainly on the individual’s behaviour. Detailed behavioural analyses were useful for managing a few captive individuals of the highly endangered G. bravoana from La Gomera island. Experimental analyses of some behaviours in the endemic Hierro island lizard (G. simonyi, in danger of extinction) show that individuals may learn to recognize predator models and increase their running speeds with training.
Comparison of the Faecal Microbiota Composition Following a Dairy By-Product Supplemented Diet in Nero Siciliano and Large White × Landrace Pig Breeds
Authors: Floridia Viviana , Giuffrè Letterio , Giosa Domenico , Arfuso Francesca , Aragona Francesca , Fazio Francesco , Chen Cai , Song Chengy , Romeo Orazio , D’Alessandro Enrico
Published: July 2023

The current study compared the faecal microbiota composition of two pig breeds (autochthonous vs. commercial) to understand what happens after the integration of liquid whey in the diet and what the role of the host genetic is. The trial was conducted for 60 days, and the faecal microbiota composition was investigated at three time points, T0, T1 (after 30 days) and T2 (after 60 days) in 30 female pigs (20 commercial crossbred and 10 Nero Siciliano pigs). The animals were divided into four groups (two control and two treatment groups). Generally, in both breeds, Firmicutes (51%) and Bacteroidota (36%) were the most abundant phylum whereas Prevotella, Treponema and Lactobacillus were the most abundant genera. The two breeds have a different reaction to a liquid whey diet. In fact, as shown by PERMANOVA analysis, the liquid whey significantly (p < 0.001) affects the microbiota composition of crossbreeds while not having an effect on the microbiota of the Nero Siciliano. Despite this, in both breeds Bifidobacterium and Ruminococcus have been positively influenced by liquid whey and they promote intestinal health, improve immunity, increase performance, and feed efficiency. In conclusion, the integration of liquid whey had a different effect on the Nero Siciliano and crossbred pig breeds, emphasizing the importance of the host genetic profile in determining the faecal bacterial composition.
Study Replication: Shape Discrimination in a Conditioning Procedure on the Jumping Spider Phidippus regius
Authors: Mannino Eleonora , Regolin Lucia , Moretto Enzo , De Agrò Massimo
Published: July 2023

Spiders possess a unique visual system, split into eight different eyes and divided into two fully independent visual pathways. This peculiar organization begs the question of how visual information is processed, and whether the classically recognized Gestalt rules of perception hold true. In a previous experiment, we tested the ability of jumping spiders to associate a geometrical shape with a reward (sucrose solution), and then to generalize the learned association to a partially occluded version of the shape. The occluded shape was presented together with a broken version of the same shape. The former should be perceived as a whole shape only in the case the animals, like humans, are able to amodally complete an object partly hidden by an occluder; otherwise, the two shapes would be perceived as identical. There, the spiders learned the association but failed to generalize. Here, we present a replication of the experiment, with an increased number of subjects, a DeepLabCut-based scoring procedure, and an improved statistical analysis. The results of the experiment follow closely the direction of the effects observed in the previous work but fail to rise to significance. We discuss the importance of study replication, and we especially highlight the use of automated scoring procedures to maximize objectivity in behavioral studies.
Extract of Isatidis Radix Inhibits Lipid Accumulation in In Vitro and In Vivo by Regulating Oxidative Stress
Authors: Han Yo-Han , Kee Ji-Ye
Published: July 2023

Isatidis Radix (IR), the root of Isatis tinctoria L. belonging to Brassicaceae, has been traditionally used as a fever reducer. Although some pharmacological effects, such as anti-diabetes, anti-virus, and anti-inflammatory, have been reported, there is no study on the anti-obesity effect of IR. This study used 3T3-L1 cells, human mesenchymal adipose stem cells (hAMSCs), and a high-fat diet (HFD)-induced obese mouse model to confirm the anti-adipogenic effect of IR. Intracellular lipid accumulation in 3T3-L1 cells and hAMSCs was decreased by IR treatment.IR extract especially suppressed reactive oxygen species (ROS) production through a cluster of differentiation 36 (CD36)-AMP-activated protein kinase (AMPK) pathway. Consequently, the expressions of peroxisome proliferator-activated receptor gamma (PPARγ), CCAAT-enhancer-binding proteins alpha (C/EBPα), and fatty acid synthesis (FAS) were inhibited by IR extract. In addition, β-oxidation-related genes were also decreased by treatment of IR extract. IR inhibited weight gain through this cascade in the HFD-induced obese mouse model. IR significantly suppressed lipid accumulation in epididymal white adipose tissue (eWAT). Furthermore, the administration of IR extract decreased serum free fatty acid (FFA), total cholesterol (TC), and LDL cholesterol, suggesting that it could be a potential drug for obesity by inhibiting lipid accumulation.
The Effect of Dietary Patterns and Nutrient Intake on Oxidative Stress Levels in Pregnant Women: A Systematic Review
Authors: El Sherbiny Samar , Squillacioti Giulia , Colombi Nicoletta , Ghelli Federica , Lenta Elena , Dalla Costa Cloè , Bono Roberto
Published: July 2023

During pregnancy, reactive oxygen species (ROS) may physiologically increase due to changes and growth of mother and fetal tissues. Consequently, oxidative stress (OS) may occur and be involved in the onset of pregnancy and newborn complications. Among exogenous antioxidant sources, diet is a cost-effective prevention strategy supporting the health of mothers and newborns; however, there is still a lack of nutritional education during pregnancy interviews. This review aims to systematically summarize the knowledge on the association between OS and diet during pregnancy. Four electronic databases (PubMed Central, EMBASE, Web of Science, and Food Science and Technology Abstracts) were searched on 22 December 2022. Among 4162 records, 13 original articles were finally included. Overall, 80% of the studies considered dietary patterns as exposure and 60% of them assessed the association with malondialdehyde levels in blood and urine. Three studies analyzed the influence of daily intakes of fruit and vegetables on different OS biomarkers (malondialdehyde, nitric oxide and 8-hydroxy-2′-deoxyguanosine). Among studies exploring dietary fat intakes (39%), 80% focused on polyunsaturated fatty acids, finding a positive association with glutathione peroxidase, biopirryn and isoprostane levels, respectively. Four studies analyzed vitamin intakes and 50% of them in association with 8-hydroxy-2′-deoxyguanosine.
Evaluation of Chemical Compositions and the Antioxidant and Cytotoxic Properties of the Aqueous Extract of Tri-Yannarose Recipe (Areca catechu, Azadirachta indica, and Tinospora crispa)
Authors: Sanpinit Sineenart , Wetchakul Palika , Chonsut Piriya , Prommee Nuntika , Punsawad Chuchard , Han Jaehong , Net-anong Soiphet
Published: July 2023

Tri-Yannarose is a Thai traditional herbal medicine formula composed of Areca catechu, Azadirachta indica, and Tinospora crispa. It possesses antipyretic, diuretic, expectorant, and appetite-stimulating effects. This study aimed to evaluate the antioxidant activities, cytotoxicity, and chemical constituents of an aqueous extract following a Tri-Yannarose recipe and its plant ingredients. The phytochemical analysis was performed using LC-QTOF-MS. Antioxidant activities were determined using DPPH, ABTS, TPC, TFC, FRAP, NBT, MCA, and ORAC assays. Cytotoxicity was investigated using a methyl thiazol tetrazolium (MTT) assay. In addition, the relationship between the chemical composition of Tri-Yannarose and antioxidant activities was investigated by examining the structure–activity relationship (SAR). The results of the LC-QTOF-MS analysis revealed trigonelline, succinic acid, citric acid, and other chemical constituents. The aqueous extract of the recipe showed significant scavenging effects against ABTS and DPPH radicals, with IC50 values of 1054.843 ± 151.330 and 747.210 ± 44.173 µg/mL, respectively. The TPC of the recipe was 92.685 mg of gallic acid equivalent/g of extract and the TFC was 14.160 mg of catechin equivalent/g of extract. All extracts demonstrated lower toxicity in the Vero cell line according to the MTT assay. In addition, the SAR analysis indicated that prenyl arabinosyl-(1–6)-glucoside and quinic acid were the primary antioxidant compounds in the Tri-Yannarose extract. In conclusion, this study demonstrates that Tri-Yannarose and its plant ingredients have potent antioxidant activities with low toxicity. These results support the application of the Tri-Yannarose recipe for the management of a range of disorders related to oxidative stress.
Oxidative Stress in Obstructive Sleep Apnea Syndrome: Putative Pathways to Hearing System Impairment
Authors: Mastino Pierluigi , Rosati Davide , de Soccio Giulia , Romeo Martina , Pentangelo Daniele , Venarubea Stefano , Fiore Marco , Meliante Piero Giuseppe , Petrella Carla , Barbato Christian , Minni Antonio
Published: July 2023

Introduction: OSAS is a disease that affects 2% of men and 4% of women of middle age. It is a major health public problem because untreated OSAS could lead to cardiovascular, metabolic, and cerebrovascular complications. The more accepted theory relates to oxidative stress due to intermittent hypoxia, which leads, after an intense inflammatory response through multiple pathways, to endothelial damage. The objective of this study is to demonstrate a correlation between OSAS and hearing loss, the effect of the CPAP on hearing function, and if oxidative stress is also involved in the damaging of the hearing system. Methods: A review of the literature has been executed. Eight articles have been found, where seven were about the correlation between OSAS and the hearing system, and only one was about the CPAP effects. It is noted that two of the eight articles explored the theory of oxidative stress due to intermittent hypoxia. Results: All studies showed a significant correlation between OSAS and hearing function (p < 0.05).Conclusions: Untreated OSAS affects the hearing system at multiple levels. Oxidative stress due to intermittent hypoxia is the main pathogenetic mechanism of damage. CPAP has no effects (positive or negative) on hearing function. More studies are needed, with the evaluation of extended high frequencies, the execution of vocal audiometry in noisy environments, and the evaluation of potential biomarkers due to oxidative stress.
Peroxiredoxin V Protects against UVB-Induced Damage of Keratinocytes
Authors: Kim Sin Ri , Park Ji Won , Lee Byung-Hoon , Lim Kyung Min , Chang Tong-Shin
Published: July 2023

Ultraviolet B (UVB) irradiation generates reactive oxygen species (ROS), which can damage exposed skin cells. Mitochondria and NADPH oxidase are the two principal producers of ROS in UVB-irradiated keratinocytes. Peroxiredoxin V (PrxV) is a mitochondrial and cytosolic cysteine-dependent peroxidase enzyme that robustly removes H2O2. We investigated PrxV’s role in protecting epidermal keratinocytes against UVB-induced ROS damage. We separated mitochondrial and cytosolic H2O2 levels from other types of ROS using fluorescent H2O2 indicators. Upon UVB irradiation, PrxV-knockdown HaCaT human keratinocytes showed higher levels of mitochondrial and cytosolic H2O2 than PrxV-expressing controls. PrxV depletion enhanced hyperoxidation-mediated inactivation of mitochondrial PrxIII and cytosolic PrxI and PrxII in UVB-irradiated keratinocytes. PrxV-depleted keratinocytes exhibited mitochondrial dysfunction and were more susceptible to apoptosis through decreased oxygen consumption rate, loss of mitochondrial membrane potential, cardiolipin oxidation, cytochrome C release, and caspase activation. Our findings show that PrxV serves to protect epidermal keratinocytes from UVB-induced damage such as mitochondrial dysfunction and apoptosis, not only by directly removing mitochondrial and cytosolic H2O2 but also by indirectly improving the catalytic activity of mitochondrial PrxIII and cytosolic PrxI and PrxII. It is possible that strengthening PrxV defenses could aid in preventing UVB-induced skin damage.
Study of Information Dissemination in Hypernetworks with Adjustable Clustering Coefficient
Authors: Li Pengyue , Wei Liang , Ding Haiping , Li Faxu , Hu Feng
Published: July 2023

The structure of a model has an important impact on information dissemination. Many information models of hypernetworks have been proposed in recent years, in which nodes and hyperedges represent the individuals and the relationships between the individuals, respectively. However, these models select old nodes based on preference attachment and ignore the effect of aggregation. In real life, friends of friends are more likely to form friendships with each other, and a social network should be a hypernetwork with an aggregation phenomenon. Therefore, a social hypernetwork evolution model with adjustable clustering coefficients is proposed. Subsequently, we use the SIS (susceptible–infectious–susceptible) model to describe the information propagation process in the aggregation-phenomenon hypernetwork. In addition, we establish the relationship between the density of informed nodes and the structural parameters of the hypernetwork in a steady state using the mean field theory. Notably, modifications to the clustering coefficients do not impact the hyperdegree distribution; however, an increase in the clustering coefficients results in a reduced speed of information dissemination. It is further observed that the model can degenerate to a BA (Barabási–Albert) hypernetwork by setting the clustering coefficient to zero. Thus, the aggregation-phenomenon hypernetwork is an extension of the BA hypernetwork with stronger applicability.
Possibility of Using Vitreous Enamel Waste in the Construction Industry as the Concept of Cleaner Production
Authors: Gulicovski Jelena , Kragović Milan , Nikolić Katarina , Rosić Milena , Ristić Nenad , Janković-Častvan Ivona , Stojmenović Marija
Published: July 2023

Waste vitreous enamels from the heating device production process were used for partial replacement of cement in the mortar and concrete production industry. This waste, due to the high content of heavy metals, is classified as hazardous waste. At the same time, waste vitreous enamels possess pozzolanic activity and belong to class 15 (WEP—generated during the production process of heating devices, premix technology), that is 5 (WETM—generated during the production process of heating devices, classic technology) of pozzolanic materials. The purpose of this research was to develop new composites from these wastes to reduce the deposition of the toxic compounds and reduce their environmental impact. The chemical and physical-chemical characterization and pozzolanic activity of the raw waste materials were studied by a mixture of complementary methods, as well as physical-mechanical characterization and a leaching test of mortar and concrete composites. The results indicate that the replacement of cement with WEP up to 30%, or with WETM up to 20% does not significantly affect the quality of concrete in comparison to the quality of the reference concrete prepared with 100% cement. The leaching test showed no significant release of toxic elements for both obtained composites.
Experimental and Numerical Study of the Strength Performance of Deep Beams with Perforated Thin Mild Steel Plates as Shear Reinforcement
Authors: Chai Khem Fei , Woon Kai Siong , Wong Jee Khai , Lim Jee Hock , Lee Foo Wei , Lee Yee Ling
Published: July 2023

This study aims to investigate a new shear reinforcement method which utilizes thin mild steel (TMS) plates as shear reinforcement in deep beams to replace conventional reinforcement. Thirteen reinforced concrete deep beam specimens with three different plate thicknesses and four varying perforated hole arrangements on the TMS plates were experimentally tested to determine the load-carrying capacity and crack pattern. The experimental results indicate that the 2.0 mm thick TMS plate has the highest load-carrying capacity. Among the four different hole arrangements on the TMS plates, the perforated plates with a three-column hole arrangement show the best performance in terms of load-carrying capacity, with a 2.9% increment against the control beam specimen. The specimens also demonstrated compatible elastic stiffness with the control beam that used conventional shear links. This shows that TMS plates have the potential to replace conventional shear links in deep beams. This proposed method also changed the failure mode from conventional diagonal shear tension failure to a combination of flexural failure and shear deformation. A numerical model was developed and was found to have a good correlation with the experimental results, demonstrating potential for use in future parametric investigations on deep beams and cost reduction in future experimental work.
Circularly Polarized High-Gain Fabry-Perot Cavity Antenna with High Sidelobe Suppression
Authors: Hussain Muhammad , Lee Kyung-Geun , Kim Dongho
Published: July 2023

The proposed design approach improves the circularly polarized Fabry-Perot cavity antenna (CP-FPCA) by increasing gain and sidelobe suppression (SLS) while reducing the axial ratio (AR) and cross-polarization levels. Conventional CP-FPC antennas have a high AR due to the lack of independent control over circular polarization conditions. The solution proposes a double-layered circularly polarized partially reflecting surface (CP-PRS) that independently controls the circular polarization conditions at the design frequency f0 (10 GHz) for equal magnitudes and at a ±90° phase difference between orthogonal components of the transmitted waves. The PRS and artificial magnetic conductor (AMC) unit cells are employed to satisfy Trentini’s beamforming condition, leading to increased gain and SLS and lowered AR and cross-polarization levels. Consequently, the proposed CP-FPCA provides a 15.4 dBi high gain with 25.3% aperture efficiency and more than 23.5 dB high SLS in each plane. Moreover, it achieves an AR lowered by 0.12 dB and a cross-polarization level below −42 dB. A strong correlation between the simulations and experiments proves the practicality of our proposal.
Bi-SQUID Versus dc SQUID in Flux-Driven Traveling-Wave Parametric Amplifier
Authors: Nikolaeva Alena N. , Kornev Victor K. , Kolotinskiy Nikolay V.
Published: July 2023

Characteristics of artificial waveguide lines composed of finite-size artificial cells are analyzed and discussed with relation to designing traveling-wave parametric amplifiers. From this point of view, the flux-driven amplifier suggested recently can be considered as the most successful amplifier design. To increase dynamic range of the amplifier, dc SQUID cells of the artificial line in use can be substituted for bi-SQUID cells. The 1 dB compression points of the amplifier gain are calculated and compared for both types of cells.
A Simplified Silty Sand Model
Authors: Kaewhanam Nopanom , Chaimoon Krit
Published: July 2023

A unified critical state model has been developed for both clean sand and silty sand using the modified Cam-clay model (MCC). The main feature of the proposed model is a new critical state line equation in the e-ln(p) plane that is capable of handling both straight and curved test results. With this feature, the error in calculating plastic volumetric strain is, in theory, eliminated. Another crucial feature of the model is the transformed stress tensor based on the SMP (spatially mobilized plane) criterion, which takes into account the proper shear yield and failure of soil under three-dimensional stresses. Additionally, the proposed model applies the intergranular void ratio with the fines influence factor for silty sand. Only eight soil parameters are required for clean sand, and a total number of twelve soil parameters are needed for silty sand. This model not only enhances the predictive accuracy for granular soils but also broadens the applicability of the model to encompass silty sand in both drained and undrained analyses.
Innovative Tool to Determine Radiative Heat Transfer Inside Spherical Segments
Authors: Cabeza-Lainez Joseph
Published: July 2023

The classic equations used to find the form factor inside fragments of spheres are often unassailable. The main difficulties that they present lie in iterative integrations effected over curved surfaces. The typical simulation software for this kind of issue is not capable of tackling the drawbacks that appear in the process, among them we could cite the impossibility of discretizing curved shapes with equal matching tiles, whether triangles or rectangles, especially when we arrive at the contour elements. The current type of cylindrical tiles employed for the calculation of spheres, due to incoherence in curvature, presents a significant array of gaps that render the whole procedure inadequate and inconsistent. To countermeasure this drawback, the recent finding of some innovative principles by the present author has provided a sure and exact path towards the solution of the problem in the frequent case of a volume enclosed within a spherical fragment and two limiting sections of the said sphere placed at arbitrary positions. The coherent application of such postulates by virtue of form factor algebra leads to an encompassing expression which solely requires the input of the surface areas of the involved shapes and, thus, avoids the lengthy resort to integration. A relevant number of cases in radiative heat transfer simulation, that cannot be solved by any other method, become feasible and accurate. Since the new tool can be implemented as an algorithm for simulation software, pivotal advances emerge in the complex domain of radiation which are applicable for the lighting industry, building simulations, and aerospace technologies, among others.
Developing an Active Microfluidic Pump and Mixer Driven by AC Field-Effect-Mediated Induced-Charge Electro-Osmosis of Metal–Dielectric Janus Micropillars: Physical Perspective and Simulation Analysis
Authors: Liu Weiyu , Tao Ye , Chen Yaoyao , Ge Zhenyou , Chen Junshuo , Li Yanbo
Published: July 2023

We propose herein a novel microfluidic approach for the simultaneous active pumping and mixing of analytes in a straight microchannel via the AC field-effect control of induced-charge electro-osmosis (ICEO) around metal–dielectric solid Janus cylinders of inherent inhomogeneous electrical polarizability immersed in an electrolyte solution. We coin the term “Janus AC flow field-effect transistor (Janus AC-FFET)” to describe this interesting physical phenomenon. The proposed technique utilizes a simple device geometry, in which one or a series of Janus microcylinders are arranged in parallel along the centerline of the channel’s bottom surface, embedding a pair of 3D sidewall driving electrodes. By combining symmetry breaking in both surface polarizability and the AC powering scheme, it is possible, on demand, to adjust the degree of asymmetry of the ICEO flow profile in two orthogonal directions, which includes the horizontal pump and transversal rotating motion. A comprehensive mathematical model was developed under the Debye–Hückel limit to elucidate the physical mechanism underlying the field-effect-reconfigurable diffuse-charge dynamics on both the dielectric and the metal-phase surfaces of the Janus micropillar. For innovation in applied science, an advanced microdevice design integrating an array of discrete Janus cylinders subjected to two oppositely polarized gate terminals is recommended for constructing an active microfluidic pump and mixer, even without external moving parts. Supported by a simulation analysis, our physical demonstration of Janus AC-FFET provides a brand-new approach to muti-directional electro-convective manipulation in modern microfluidic systems.
A Non-Local Non-Homogeneous Fractional Timoshenko System with Frictional and Viscoelastic Damping Terms
Authors: Mesloub Said , Alhazzani Eman , Eltayeb Gadain
Published: July 2023

We are devoted to the study of a non-local non-homogeneous time fractional Timoshenko system with frictional and viscoelastic damping terms. We are concerned with the well-posedness of the given problem. The approach relies on some functional analysis tools, operator theory, a priori estimates and density arguments. This work can be considered as a contribution to the development of energy inequality methods, the so-called a priori estimate method inspired from functional analyses and used to prove the well-posedness of mixed problems with integral boundary conditions.
Some New Bullen-Type Inequalities Obtained via Fractional Integral Operators
Authors: Fahad Asfand , Butt Saad Ihsaan , Bayraktar Bahtiyar , Anwar Mehran , Wang Yuanheng
Published: July 2023

In this paper, we establish a new auxiliary identity of the Bullen type for twice-differentiable functions in terms of fractional integral operators. Based on this new identity, some generalized Bullen-type inequalities are obtained by employing convexity properties. Concrete examples are given to illustrate the results, and the correctness is confirmed by graphical analysis. An analysis is provided on the estimations of bounds. According to calculations, improved Hölder and power mean inequalities give better upper-bound results than classical inequalities. Lastly, some applications to quadrature rules, modified Bessel functions and digamma functions are provided as well.
Modified Wild Horse Optimizer for Constrained System Reliability Optimization
Authors: Kumar Anuj , Pant Sangeeta , Singh Manoj K. , Chaube Shshank , Ram Mangey , Kumar Akshay
Published: July 2023

The last few decades have witnessed advancements in intelligent metaheuristic approaches and system reliability optimization. The huge progress in metaheuristic approaches can be viewed as the main motivator behind further refinement in the system reliability optimization process. Researchers have intensively studied system reliability optimization problems (SROPs) to obtain the optimal system design with several constraints in order to optimize the overall system reliability. This article proposes a modified wild horse optimizer (MWHO) for SROPs and investigates the reliability allocation of two complex SROPs, namely, complex bridge system (CBS) and life support system in space capsule (LSSSC), with the help of the same process. The effectiveness of this framework based on MWHO is demonstrated by comparing the results obtained with the results available in the literature. The proposed MWHO algorithm shows better efficiency, as it provides superior solutions to SROPs.
Detection of Hindwing Landmarks Using Transfer Learning and High-Resolution Networks
Authors: Yang Yi , Liu Xiaokun , Li Wenjie , Li Congqiao , Ma Ge , Yang Guangqin , Ren Jing , Ge Siqin
Published: July 2023

Hindwing venation is one of the most important morphological features for the functional and evolutionary analysis of beetles, as it is one of the key features used for the analysis of beetle flight performance and the design of beetle-like flapping wing micro aerial vehicles. However, manual landmark annotation for hindwing morphological analysis is a time-consuming process hindering the development of wing morphology research. In this paper, we present a novel approach for the detection of landmarks on the hindwings of leaf beetles (Coleoptera, Chrysomelidae) using a limited number of samples. The proposed method entails the transfer of a pre-existing model, trained on a large natural image dataset, to the specific domain of leaf beetle hindwings. This is achieved by using a deep high-resolution network as the backbone. The low-stage network parameters are frozen, while the high-stage parameters are re-trained to construct a leaf beetle hindwing landmark detection model. A leaf beetle hindwing landmark dataset was constructed, and the network was trained on varying numbers of randomly selected hindwing samples. The results demonstrate that the average detection normalized mean error for specific landmarks of leaf beetle hindwings (100 samples) remains below 0.02 and only reached 0.045 when using a mere three samples for training. Comparative analyses reveal that the proposed approach out-performs a prevalently used method (i.e., a deep residual network). This study showcases the practicability of employing natural images—specifically, those in ImageNet—for the purpose of pre-training leaf beetle hindwing landmark detection models in particular, providing a promising approach for insect wing venation digitization.
Epigenetic Reader Bromodomain-Containing Protein 4 in Aging-Related Vascular Pathologies and Diseases: Molecular Basis, Functional Relevance, and Clinical Potential
Authors: Zheng Xiaoxu , Diktonaite Kotryna , Qiu Hongyu
Published: July 2023

Aging is a key independent risk factor of various vascular diseases, for which the regulatory mechanisms remain largely unknown. Bromodomain-containing protein 4 (BRD4) is a member of the Bromodomain and Extra-Terminal domain (BET) family and is an epigenetic reader playing diverse roles in regulating transcriptional elongation, chromatin remodeling, DNA damage response, and alternative splicing in various cells and tissues. While BRD4 was initially recognized for its involvement in cancer progression, recent studies have revealed that the aberrant expression and impaired function of BRD4 were highly associated with aging-related vascular pathology, affecting multiple key biological processes in the vascular cells and tissues, providing new insights into the understanding of vascular pathophysiology and pathogenesis of vascular diseases. This review summarizes the recent advances in BRD4 biological function, and the progression of the studies related to BRD4 in aging-associated vascular pathologies and diseases, including atherosclerosis, aortic aneurism vascular neointima formation, pulmonary hypertension, and essential hypertension, providing updated information to advance our understanding of the epigenetic mechanisms in vascular diseases during aging and paving the way for future research and therapeutic approaches.
Cognitive Gain in Digital Foreign Language Learning
Authors: Klimova Blanka , Pikhart Marcel
Published: July 2023

This systematic review examines the potential of digital language learning in contributing to students’ cognitive gains. The study reviews existing research on the relationship between digital language learning and cognitive benefits, with a focus on enhanced problem-solving skills, memory, and multitasking ability. The research questions explored in this study are (1) does digital language learning contribute to cognitive gains in foreign language education? and (2) what are the pedagogical implications for cognitive improvement in digital foreign language education? The study employs the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) methodology to identify and analyze relevant research articles. The results of the review suggest that working with printed texts may be more effective for cognitive gains compared to electronic texts. Additionally, implementing more senses through digital language education appears to be beneficial for cognitive gains. Thus, several pedagogical implications emerge for promoting cognitive improvement in digital foreign language education. Firstly, it is crucial to implement techniques and strategies that best align with students’ language needs in a digital learning environment, whether it involves pen-and-paper activities or a flipped classroom approach. Secondly, exposing students to a variety of techniques that engage multiple senses can have a positive impact on cognitive gains. Finally, providing students with feedback is essential to maintain their motivation and foster continued progress in their foreign language studies.
The Effect of Loneliness on Nomophobia: A Moderated Mediation Model
Authors: Heng Shupeng , Gao Qiwei , Wang Minghui
Published: July 2023

A large number of studies have shown that loneliness is a positive predictor of nomophobia (no mobile phobia), but little research has examined the mechanism of this association. Drawing on attachment theory, the present study constructs a moderated mediation model to examine whether smartphone attachment mediates the relation between loneliness and nomophobia and whether this mediating process is moderated by attachment anxiety. A total of 598 college students in China were recruited to complete a questionnaire to measure loneliness, smartphone attachment, attachment anxiety, and nomophobia. A moderated mediation analysis was conducted. Our findings revealed that after controlling for gender, loneliness is positively associated with nomophobia. Meanwhile, smartphone attachment plays a mediating role in the relationship between loneliness and nomophobia. Furthermore, attachment anxiety moderates the mediated path through smartphone attachment, such that an indirect effect is much stronger for individuals with higher attachment anxiety relative to those with low attachment anxiety. The present study provides new insight into the complex processes in the association between loneliness and nomophobia, and the results have important theoretical and practical implications.
Assessing the Potential of Robotics Technology for Enhancing Educational for Children with Autism Spectrum Disorder
Authors: Alghamdi Maha , Alhakbani Noura , Al-Nafjan Abeer
Published: July 2023

Robotics technology has been increasingly used as an educational and intervention tool for children with autism spectrum disorder (ASD). However, there remain research issues and challenges that need to be addressed to fully realize the potential benefits of robot-assisted therapy. This systematic review categorizes and summarizes the literature related to robot educational/training interventions and provides a conceptual framework for collecting and classifying these articles. The challenges identified in this review are classified into four levels: robot-level, algorithm-level, experimental-research-level, and application-level challenges. The review highlights possible future research directions and offers crucial insights for researchers interested in using robots in therapy. The most relevant findings suggest that robot-assisted therapy has the potential to improve social interaction, communication, and emotional regulation skills in children with ASD. Addressing these challenges and seeking new research avenues will be critical to advancing the field of robot-assisted therapy and improving outcomes for children with ASD. This study serves as a roadmap for future research in this important area.
Numerical Investigation on the Performance of Exterior Beam–Column Joints Reinforced with Shape Memory Alloys
Authors: Higazey Mahmoud M. , Alshannag Mohammad J. , Alqarni Ali S.
Published: July 2023

Upgraded design standards coupled with the damage caused by natural disasters have led to the development of smart materials with the potential to modernize current construction practices. This investigation proposes a nonlinear finite element (FE) model for evaluating the performance of beam–column joints (RC-BCJ) reinforced with shape memory alloys (SMA) and steel rebars. The model was validated based on accredited experimental data, followed by parametric analysis in ABAQUS to optimize the use of SMA bars for enhancing the seismic resistance of RC-BCJ without compromising their energy dissipation capacity. Parameters investigated include the (a) SMA–steel reinforcement ratio, (b) lengths of SMA bars, (c) elastic modulus of SMA, (d) compressive strength of concrete, and (e) axial load applied on the column. The finite element simulation results indicated that the model was capable of predicting the optimum length of SMA bars sufficient for relocating the plastic hinge away from the face of the column along the beam. Further, simulation results proved that the use of SMA bars in conjunction with steel reinforcement could be considered as an effective tool for enhancing the seismic performance of RC-BCJ joints. Among the parameters investigated, high-strength concrete was the most effective in improving joint resistance.
Optimal Tuned Inerter Dampers for Vibration Control Performance of Adjacent Building Structures
Authors: Kang Xiaofang , Tang Jianjun , Li Feng , Wu Jian , Wei Jiachen , Huang Qiwen , Li Zhi , Zhang Fuyi , Sheng Ziyi
Published: July 2023

Under the effect of strong earthquakes, collisions or excessive inter-story displacements may occur between adjacent building structures to the extent that the building structure is damaged. The traditional seismic measures for these structures can no longer meet the needs in practical engineering. In this paper, we propose the application of parallel and serial TID-based control systems in adjacent buildings as an example of a single-story adjacent building, and use it to form a new adjacent building seismic reduction structure. In this paper, the dynamic characteristics and design parameter optimization of the vibration control system are investigated by means of the Monte Carlo pattern search method and H2 norm theory. The results show that the introduction of serial and parallel TID in adjacent building structures can effectively improve the seismic resistance of adjacent buildings. The problem of vibration amplification caused by resonance is obviously improved, which is especially evident in the adjacent building structure vibration control system based on parallel TID. The vibration control system of adjacent building structures based on parallel TID is more robust. When optimizing the right building, the damping requirement of the TID decreases for the vibration control system based on parallel TID as the adjacent building mass ratio increases, while the damping requirement of the TID increases for the vibration control system based on serial TID. In both vibration control systems, the difference in the optimal inertial mass ratio is small. In practice, a moderate increase in the difference between adjacent building masses can have a positive effect on the vibration control performance of the systems. The main contribution of this paper is to fill the research gap in parallel and serial TID applications for adjacent building vibration reduction.
Investigation of Microclimate Parameter Assurance in Schools with Natural Ventilation Systems
Authors: Makaveckas Tomas , Bliūdžius Raimondas , Alavočienė Sigita , Paukštys Valdas , Brazionienė Ingrida
Published: July 2023

Slow population growth has limited the construction of new schools, leading to the renovation of existing buildings to achieve energy efficiency goals. While improvements are made to thermal insulation, heating and ventilation systems often remain outdated, presenting challenges in maintaining indoor air quality (IAQ) in schools, where children spend a significant amount of time in densely populated classrooms, and whose health is more affected by IAQ than that of adults. Therefore, this study assessed the possibilities to achieve IAQ requirements in schools ventilated by opening the windows by monitoring the carbon dioxide (CO2) concentration, temperature, and relative humidity (RH) fluctuation. The results of the study have shown that it is not feasible to achieve the defined IAQ parameters in classrooms through window opening alone. The measured CO2 concentration during lessons in many cases exceeded the limit value of 1000 ppm and did not decrease to ambient levels when the windows were opened during the break. Additionally, the internal air temperature dropped below the normative when lessons started, and RH was significantly below the recommended minimum value on all days. It was also found that the use of thermal energy decreases evenly because of inefficient air change leaving no direct economic leverage for the installation of efficient ventilation systems.