bluuebunny/crossref_metadata_2025 huggingface dataset:
Ethanol Metabolism in the Liver, the Induction of Oxidant Stress, and the Antioxidant Defense System
Authors: Contreras-Zentella Martha Lucinda , Villalobos-García Daniel , Hernández-Muñoz Rolando
Published: June 2022

The liver metabolizes ethanol through three enzymatic pathways: alcohol dehydrogenase (ADH), cytochrome p450 (also called MEOS), and catalase. Alcohol dehydrogenase class I (ADH1) is considered the most important enzyme for the metabolism of ethanol, MEOS and catalase (CAT) are considered minor alternative pathways. However, contradicting experiments suggest that the non-ADH1 pathway may have a greater relevance for the metabolism of ethanol than previously thought. In some conditions, ethanol is predominately metabolized to acetaldehyde via cytochrome P450 family 2 (CYP2E1), which is involved in the generation of reactive oxygen species (ROS), mainly through electron leakage to oxygen to form the superoxide (O2•−) radical or in catalyzed lipid peroxidation. The CAT activity can also participate in the ethanol metabolism that produces ROS via ethanol directly reacting with the CAT-H2O2 complex, producing acetaldehyde and water and depending on the H2O2 availability, which is the rate-limiting component in ethanol peroxidation. We have shown that CAT actively participates in lactate-stimulated liver ethanol oxidation, where the addition of lactate generates H2O2, which is used by CAT to oxidize ethanol to acetaldehyde. Therefore, besides its known role as a catalytic antioxidant component, the primary role of CAT could be to function in the metabolism of xenobiotics in the liver.
Seismic Stability for 3D Two-Step Slope Governed by Non-Linearity in Soils Using Modified Pseudo-Dynamic Approach
Authors: Yang Yushan , Zhou De
Published: June 2022

Seismic events are an active factor in causing slope instability, and the existing pseudo-dynamic method ignores some practical engineering conditions. In this paper, the seismic stability of three-dimensional (3D) two-step slopes is evaluated utilizing the modified pseudo-dynamic method based on the kinematical approach of limit analysis, in which the nonlinear characteristics of soil are considered using the generalized tangent technique. A 3D horn-like rotational failure mechanism is established to solve internal energy dissipation and external force work, in which the seismic work is considered in addition to the soil weight work and obtained by the layer-wise summation method. Based on the force-increase technique, the analytical expression for the safety factor (FS) of 3D two-step slopes is derived more readily. To verify the reliability of the new expression, the present results are compared with already posted solutions and the original pseudo-dynamic solutions. Ultimately, the sensitivity discussions are carried out to investigate the impacts of various factors on slope stability. This has some significance for the design and safety of 3D two-step slopes.
Bayesian Mixture Model to Estimate Freeway Travel Time under Low-Frequency Probe Data
Authors: Kim Hyungjoo , Ye Lanhang
Published: June 2022

This study develops a novel estimation method under low-frequency probe data using the Bayesian approach. Given the challenges in estimating travel time under low-frequency probe data and prior distribution of the parameters in a traditional Bayesian approach, the proposed algorithm adopts a historical data-based data-driven method according to the characteristics of travel time regularity. Due to the variability of travel times during peak periods, this paper adopts a mixture distribution of travel times in the Bayesian approach rather than traditional single distribution. The Gibbs sampling method with a burn-in period is used to generate a series of sampling sequences from an unknown joint posterior distribution for estimating the posterior distribution of the parameters. The proposed algorithm is tested using traffic data collected from the Korean freeway section from Giheung IC to Dongtan IC. Both MAPE and RMSE of the estimation results show that the proposed method has the smallest deviation from the ground truth travel time compared to the simple mean and moving average methods. Moreover, the proposed Bayesian estimation yields the smallest standard deviation of MAPE for all test days. The credible intervals for estimated travel times show that the proposed method provides good accuracy in estimating travel time reliability.
Wavelet Time-Scale Modeling of Brand Sales and Prices
Authors: Alanazi Tawfeeq M. , Ben Mabrouk Anouar
Published: June 2022

Marketing is the way we ensure our sales are the best in the market, our prices the most accessible, and our clients satisfied, thus ensuring our brand has the widest distribution. This requires sophisticated and advanced understanding of the whole related network. Indeed, marketing data may exist in different forms such as qualitative and quantitative data. However, in the literature, it is easily noted that large bibliographies may be collected about qualitative studies, while only a few studies adopt a quantitative point of view. This is a major drawback that results in marketing science still focusing on design, although the market is strongly dependent on quantities such as money and time. Indeed, marketing data may form time series such as brand sales in specified periods, brand-related prices over specified periods, market shares, etc. The purpose of the present work is to investigate some marketing models based on time series for various brands. We will precisely study the effect of the time scale on the persistence of brand sales in the market and on the forecasting of such persistence, according to the characteristics of the brand and the related market competition or competitors. Our study is based on a sample of Saudi brands during the period 22 November 2017 to 30 December 2021.
Validation of the Maltese Adaptive Auditory Speech Test (AAST)
Authors: Miggiani Pauline , Coninx Frans , Schaefer Karolin
Published: June 2022

The Adaptive Auditory Speech Test (AAST) was developed to record the Speech Recognition Threshold (SRT) in children in quiet or with background noise. AAST is an interlingually valid and reliable standardised tool with speech material developed in several languages. The Maltese version of the Adaptive Auditory Speech Test (AAST) was developed to examine the speech recognition skills of 208 children and 40 Maltese-speaking adults in quiet, noise and high frequency. The aims were to determine the norms in these three settings in adults and children aged 4 years and older. The Maltese version of AAST confirms an age dependent norm threshold with a significant improvement in threshold being observed as children grow older, similar to other AAST versions. This was evident across the three test settings. An approximate difference of 10 dB was also noted between 4-year-old and 10-year-old children in AAST in quiet. Thresholds of 10-year-olds and adults were similar in both the quiet and high frequency versions. Implications for post Universal Newborn Hearing Screening using these tools are addressed.
A Specific and Sensitive Aptamer-Based Digital PCR Chip for Salmonella typhimurium Detection
Authors: Suo Yuanjie , Yin Weihong , Zhu Qiangyuan , Wu Wenshuai , Cao Wenjian , Mu Ying
Published: June 2022

Food poisoning and infectious diseases caused by Salmonella typhimurium (S. typhimurium) are serious public health concerns for human health and food safety. The diversity and complexity of food matrices pose great challenges for rapid and ultra-sensitive detection of S. typhimurium in food samples. A method capable of identification, detection, and quantification of S. typhimurium is essential for addressing these issues. In this study, aptamer-coated magnetic beads (Apt-MBs) are employed as capture bio-probes to specifically and selectively concentrate S. typhimurium in food samples. A self-priming chip-based digital PCR was then presented as another biosensor for on-site detection and quantification of S. typhimurium cells. The chip we developed was robust and did not require any external power for sample loading. The combination of Apt-MBs with an on-chip digital detection realized the integration into lab-on-a-chip-based biosensors for on-site monitoring of foodborne pathogens. It was possible to capture and detect S. typhimurium cells as low as 90 CFU/reaction with a capture efficiency of 94.5%. Additionally, the whole process only took about 2 h. This unique platform could also be used to monitor other target bacteria with high specificity and sensitivity by utilizing different aptamers. Furthermore, the platform has potential applications in point-of-care testing in the future.
On the Feasibility and Efficiency of Self-Powered Green Intelligent Highways
Authors: Minea Marius , Dumitrescu Cătălin Marian
Published: June 2022

(1) Background: The present development of transport networks focusses on the better management of fuels and energy and the preservation of the environment. To fulfill these desiderates, some countries have already reconsidered the deployment plans of new highways. This research studies the feasibility of less polluting, quasi-self-powered, intelligent highway infrastructure functional blocks accommodating functions for the future introduction of smart wireless sensor grids and connected autonomous vehicles. Subject of investigation are the possibilities of energy harvesting, and the intelligent management of resources. (2) Methods: the research investigates the main technologies for energy harvesting and recommends an optimal solution. It also proposes a framework for the intelligent, AI-based management of energy and the use of an optimized backup solution relying on 5G beamforming for energy supply of the local wireless sensing network devices; (3) Results: recommendations are made for the best energy harvesting solution, an architecture of the energy management system, an algorithm for energy management and backup solution based on 5G beamforming; (4) Conclusions: the research emphasizes the advantages and drawbacks for different solutions regarding energy harvesting in an intelligent green highway scenario with a focus on the infrastructure developed to accommodate future connected and autonomous vehicles. The term “intelligent highway” must be understood in the automotive industry to describe a network of roads where cars communicate with the infrastructure and among themselves for the purpose of avoiding congestion and performing the seamless operation of services, and a space where cars and infrastructure cooperatively process information for obtaining better road safety, less pollution, and efficient energy management. With the recent recession of conventional fuel availability and the increase in prices, a solution to improving autonomy of both cars and infrastructure might be welcomed.
Antibacterial and Cytotoxicity Evaluation of New Hydroxyapatite-Based Granules Containing Silver or Gallium Ions with Potential Use as Bone Substitutes
Authors: Pajor Kamil , Michalicha Anna , Belcarz Anna , Pajchel Lukasz , Zgadzaj Anna , Wojas Filip , Kolmas Joanna
Published: June 2022

The aim of the current work was to study the physicochemical properties and biological activity of different types of porous granules containing silver or gallium ions. Firstly, hydroxyapatites powders doped with Ga3+ or Ag+ were synthesized by the standard wet method. Then, the obtained powders were used to fabricate ceramic microgranules (AgM and GaM) and alginate/hydroxyapatite composite granules (AgT and GaT). The ceramic microgranules were also used to prepare a third type of granules (AgMT and GaMT) containing silver or gallium, respectively. All the granules turned out to be porous, except that the AgT and GaT granules were characterized by higher porosity and a better developed specific surface, whereas the microgranules had very fine, numerous micropores. The granules revealed a slow release of the substituted ions. All the granules except AgT were classified as non-cytotoxic according to the neutral red uptake (NRU) test and the MTT assay. The obtained powders and granules were subjected to various antibacterial test towards the following four different bacterial strains: Staphylococcus aureus, Staphylococcus epidermidis, Pseudomonas aeruginosa and Escherichia coli. The Ag-containing materials revealed high antibacterial activity.
Odonata Assemblages as a Tool to Assess the Conservation Value of Intermittent Rivers in the Mediterranean
Authors: Vilenica Marina , Rebrina Fran , Ružanović Lea , Gulin Vesna , Brigić Andreja
Published: June 2022

Intermittent rivers, lotic habitats that cease to flow during the dry periods of the year, make up a large proportion of the world’s inland waters and are an important source of water in arid regions such as the Mediterranean. Yet, water resources and riparian habitats in the Mediterranean regions are under diverse anthropogenic pressures, including land-use change. Odonata are widely used as a valuable tool for assessing freshwater ecosystems. Hence, with the aim of inspecting the conservation value of intermittent rivers in the Mediterranean based on the assemblages they support, we studied Odonata adults at four intermittent Mediterranean rivers in the Dinaric Western Balkans ecoregion with respect to the surrounding land-cover heterogeneity. We analyzed several diversity and conservation indices and recorded significant differences in Odonata species richness and Croatian Conservation Odonatological index among the studied rivers. Our findings showed that land use, as a long-term moderate anthropogenic impact, can enhance land-cover heterogeneity and in some cases even lead to increased Odonata diversity in intermittent rivers in the Mediterranean. Intermittent rivers provide habitat for several threatened Odonata species, suggesting the importance of Odonata in planning the conservation activities in these vulnerable ecosystems.
Multi-Scale Effects of Landscape Stucture on Epigaeic Arthropods Diversity in Arable Land System: A Case in Changtu County of Northern China
Authors: Zhang Yufei , Yang Yujing , Bian Zhenxing , Wang Shuai
Published: June 2022

Understanding the multi-scale effects of arable land landscape on epigaeic arthropod diversity is essential for biodiversity conservation and agroecosystem services. Our study explored the overall effect of landscape elements on epigaeic arthropod diversity at three scales of landscape, habitat, and field. We selected 11 areas to sample using the trap method, and construct models of landscape elements and biodiversity data. The results showed that: (1) On the landscape scale, 1500 m was the optimal radius. Shannon’s diversity index and interspersion and juxtaposition index can explain the diversity of epigaeic arthropods at the level of 76.7%. (2) On the habitat scale (the radius less than 100 m), habitat types significantly affected the species number, Pielou evenness index, and individual number of epigaeic arthropods (p < 0.05). The distribution of epigaeic arthropods had an obvious margin effect. (3) On the field scale, we also revealed The Shannon diversity index and Pielou evenness index of herb vegetation structure can explain the change of epigaeic arthropod community structure at the level of 69.1%. We believe that an appropriate scale is the best lever to protect agricultural biodiversity. Our research can promote multi-scale integrated conservation of regional biodiversity and sustainable development of agricultural systems.
Onset Timing of Hyoid Muscles Activation during Cervical Flexion Is Position-Dependent: An EMG Study
Authors: Sageshima Hirofumi , Pavlů Dagmar , Dvořáčková Dominika , Pánek David
Published: June 2022

Due to the high prevalence of neck pain, considerable attention is paid to the function of cervical flexor muscles. Although the deep and superficial cervical flexor muscles have been evaluated, the impact of hyoid muscles on cervical flexion is still not well known. We, therefore, aimed to investigate the activation of hyoid muscles during physiological cervical flexion, and to determine the impact of different starting positions on cervical flexion muscle activation. The activities of bilateral sternocleidomastoid, scalene, suprahyoid, and infrahyoid muscles were evaluated by surface electromyography (EMG) in twenty young healthy volunteers. They performed a repetitive cervical flexion-extension movement, from neutral position of the head to the maximum flexion with the same speed set at eight seconds in a cycle, in three various positions (sitting, standing, and supine). In sitting and standing positions, the group of suprahyoid muscles was activated in advance of other cervical flexor muscles despite only significant differences were found in scalene muscles, and the activation of the group of infrahyoid muscles was time-synchronous with sternocleidomastoid muscles. On the other hand, in supine position, the activation of all measured cervical flexor muscles was significantly earlier and longer than in the other two positions. This study confirmed the empirical suggestion that hyoid muscles contributed to cervical flexion, and it confirmed that muscle activation was position dependent, even if the given movement is nearly identical.
Micellar Composition Affects Lipid Accretion Kinetics in Molecular Dynamics Simulations: Support for Lipid Network Reproduction
Authors: Kahana Amit , Lancet Doron , Palmai Zoltan
Published: June 2022

Mixed lipid micelles were proposed to facilitate life through their documented growth dynamics and catalytic properties. Our previous research predicted that micellar self-reproduction involves catalyzed accretion of lipid molecules by the residing lipids, leading to compositional homeostasis. Here, we employ atomistic Molecular Dynamics simulations, beginning with 54 lipid monomers, tracking an entire course of micellar accretion. This was done to examine the self-assembly of variegated lipid clusters, allowing us to measure entry and exit rates of monomeric lipids into pre-micelles with different compositions and sizes. We observe considerable rate-modifications that depend on the assembly composition and scrutinize the underlying mechanisms as well as the energy contributions. Lastly, we describe the measured potential for compositional homeostasis in our simulated mixed micelles. This affirms the basis for micellar self-reproduction, with implications for the study of the origin of life.
A Targeted Next-Generation Sequencing Panel to Genotype Gliomas
Authors: Guarnaccia Maria , Guarnaccia Laura , La Cognata Valentina , Navone Stefania , Campanella Rolando , Ampollini Antonella , Locatelli Marco , Miozzo Monica , Marfia Giovanni , Cavallaro Sebastiano
Published: June 2022

Gliomas account for the majority of primary brain tumors. Glioblastoma is the most common and malignant type. Based on their extreme molecular heterogeneity, molecular markers can be used to classify gliomas and stratify patients into diagnostic, prognostic, and therapeutic clusters. In this work, we developed and validated a targeted next-generation sequencing (NGS) approach to analyze variants or chromosomal aberrations correlated with tumorigenesis and response to treatment in gliomas. Our targeted NGS analysis covered 13 glioma-related genes (ACVR1, ATRX, BRAF, CDKN2A, EGFR, H3F3A, HIST1H3B, HIST1H3C, IDH1, IDH2, P53, PDGFRA, PTEN), a 125 bp region of the TERT promoter, and 54 single nucleotide polymorphisms (SNPs) along chromosomes 1 and 19 for reliable assessment of their copy number alterations (CNAs). Our targeted NGS approach provided a portrait of gliomas’ molecular heterogeneity with high accuracy, specificity, and sensitivity in a single workflow, enabling the detection of variants associated with unfavorable outcomes, disease progression, and drug resistance. These preliminary results support its use in routine diagnostic neuropathology.
Developing a Comprehensive Shipment Policy through Modified EPQ Model Considering Process Imperfections, Transportation Cost, and Backorders
Authors: Sajjad Waseem , Ullah Misbah , Khan Razaullah , Hayat Mubashir
Published: June 2022

Background: Determining the optimum shipment quantity in a traditional production system is a competitive business dimension, and developing a reliable shipment policy is decisive for long-term objectives. Currently, significant research in this domain has mainly focused on the optimum shipment lot sizing in a perfect production system without considering the imperfections in the production processes and logistics. It has been well established that the real production inventory system acts as an imperfection in the overall production management loop. Methods: This research deals with designing a new shipment policy considering the imperfections in the production processes and undertaking some influential factors, such as the transportation cost, the actual production inventory, defective items, and backorders. Results: In the developed mathematical framework, the lot-sizing problems, imperfections in the production processes, retailers, and distributors are considered with equal-sized shipment policy to attain pragmatic and real-time results. Conclusions: The developed framework considers an all-unit-discount transportation cost structure. The numerical computations, as well as sensitivity analysis, are performed to point out the specifications and validation of the proposed model.
3-(2-Diisopropylaminoethyl)-5-(4-methoxybenzylidene)thiazolidine-2,4-dione
Authors: Holota Serhii , Yushyn Ihor , Gzella Andrzej , Lesyk Roman
Published: June 2022

Thiazolidine-2,4-dione core is widely used in the medicinal chemistry of different types of potential drug-like small molecules. In the present work, the synthesis of a novel non-condensed thiazolidine-2,4-dione-bearing derivative is reported by the two-step cost-effective approach including alkylation and Knoevenagel condensation. The structure of the synthesized 3-(2-diisopropylaminoethyl)-5-(4-methoxybenzylidene)thiazolidine-2,4-dione was determined and characterized using 1H, 13C NMR, LC-MS spectra and the X-ray diffraction method.
N,N-Diethyl-3-methylbenzamide
Authors: Albert-Soriano María , Pastor Isidro M.
Published: June 2022

The development of new techniques for the preparation of organic compounds is important, with catalytic processes being key to this innovation. The development of copper-based metal-organic frameworks to promote oxidative couplings has allowed the synthesis of amides in a very effective manner. This methodology has been successfully applied to the unique preparation of the bioactive compound N,N-diethyl-3-methylbenzamide, with excellent performance (>99% conversion and 95% yield of pure isolated product) on a preparative scale. The described procedure can be classified as an excellent synthesis (EcoScale) considering environmental and economic factors based on different “green metrics” (atom economy, reaction mass efficiency, materials recovery factor, stoichiometric factor, E-factor).
Efficient Removal of Nonylphenol Contamination from Water Using Optimized Magnesium Silicate
Authors: Yan Xu , Zhang Qicai , Rao Qinxiong , Chen Shanshan , Wang Xianli , Song Wei , Cheng Lin , Guan Shuhui , Song Weiguo
Published: June 2022

Nonylphenol (NP) is considered to be an environmentally toxic, endocrine-disrupting chemical that affects humans and ecosystems. Adsorption is one of the most promising approaches for the removal of nonylphenol contamination from water. Herein, in order to design an adsorbent with high adsorption capacity, magnesium silicate with different Mg/Si ratios was successfully synthesized by a sol–gel method at 60 °C. Magnesium silicate with a Mg/Si ratio of 1:6 was found to possess the best adsorption performance, with maximum 4−NP sorption 30.84 mg/g under 25 °C and 0.2 g/L adsorbent dose. The adsorption was negatively affected by increasing adsorbent dose and temperature. The kinetics and isotherm of 4−NP adsorption by Mg/Si were well described by the pseudo−second−order and Sips model, respectively, and behavior was proven to be physisorption−enhanced by a chemical effect. Detailed characterization by XRD, BET, and SEM confirmed that the magnesium silicate possesses an amorphous, mesoporous structure. The study will contribute to the applicability of cheap magnesium silicate for removal of NP contamination in water.
Experimental Evaluation of the Concrete Damage and Pore Characteristics under Salt-Freezing Cycles
Authors: Zhou Jiguo , Wang Guihua , Xu Jun
Published: June 2022

Herein, ordinary silicate concrete specimens are prepared to study the damage law of a cement-concrete material under the effects of salt erosion and a freeze–thaw environment. NaCl, NaHCO3, and Na2SO4 solutions are separately produced, according to the characteristics of saline soil, to conduct an experimental study on the concrete characteristics during quick salt freezing cycles, and to analyse the changes in its compressive strength, mass loss, and dynamic elastic modulus (DEM) under freeze–thaw cycles. Low-field nuclear magnetic resonance (NMR) and scanning electronic microscopy are used to investigate the change in the microstructure of concrete specimens under salt freeze–thaw cycles (FTCs). The results show the loss in compressive strength, mass, DEM, and NMR spectrum signal increased by 1.5–3 times, 3–5 times, 1.5–2.5 times, and 2–4 times, respectively, for concrete specimens under 50–100 FTCs in 6.8% composite salt solution, in comparison to fresh water. Apparent spalling, decreases in the DEM, and reductions in the compressive strength occur in concrete when increasing the number of salt FTCs. The number of internal cracks in the concrete structure increase under the combined action of salt crystallization, moisture absorption, and freeze–thaw. The changes in the internal microscopic pore volume in concrete structures exhibit the same trend with changes in the macro mechanical properties of concrete. The correlation coefficients between the changes in each peak in the NUR spectrum and the changes in the compressive strength of concrete specimens under FTCs in freshwater or low-concentration salt solutions are both larger than 0.7, calculated using the grey correlation degree method. Therefore, these changes could be used as a potential evaluation index for salt frozen damage to concrete structures.
Dual-Drug Delivery via the Self-Assembled Conjugates of Choline-Functionalized Graft Copolymers
Authors: Niesyto Katarzyna , Mazur Aleksy , Neugebauer Dorota
Published: June 2022

Graft copolymers based on a choline ionic liquid (IL), [2-(methacryloyloxy)ethyl]-trimethylammonium chloride (TMAMA), were obtained by atom transfer radical polymerization. The presence of chloride counterions in the trimethylammonium groups promoted anion exchange to introduce fusidate anions (FUS, 32–55 mol.%) as the pharmaceutical anions. Both the choline-based IL copolymers and their ionic drug-carrier conjugates (FUS systems as the first type, 26–208 nm) formed micellar structures (CMC = 0.011–0.025 mg/mL). The amphiphilic systems were advantageous for the encapsulation of rifampicin (RIF, 40–67 mol.%), a well-known antibiotic, resulting in single-drug (RIF systems as the second type, 40–95 nm) and dual-drug systems (FUS/RIF as the third type, 31–65 nm). The obtained systems released significant amounts of drugs (FUS > RIF), which could be adjusted by the content of ionic units and the length of the copolymer side chains. The dual-drug systems released 31–55% FUS (4.3–5.6 μg/mL) and 19–31% RIF (3.3–4.0 μg/mL), and these results were slightly lower than those for the single-drug systems, reaching 45–81% for FUS (3.8–8.2 μg/mL) and 20–37% for RIF (3.4–4.0 μg/mL). The designed polymer systems show potential as co-delivery systems for combined therapy against drug-resistant strains using two drugs in one formula instead of the separate delivery of two drugs.
Effect of Psyllium Husk Addition on the Structural and Physical Properties of Biodegradable Thermoplastic Starch Film
Authors: Beer-Lech Karolina , Skic Anna , Skic Kamil , Stropek Zbigniew , Arczewska Marta
Published: June 2022

The research subject was the analysis of the microstructure, barrier properties, and mechanical resistance of the psyllium husk (PH)-modified thermoplastic starch films. The tensile tests under various static loading conditions were not performed by researchers for this type of material before and are essential for a more precise assessment of the material’s behavior under the conditions of its subsequent use. The film samples were manufactured by the casting method. PH addition improved starch gelatinization and caused a decrease in failure strain by 86% and an increase in failure stress by 48% compared to pure films. Fourier transform infrared spectroscopy results showed the formation of additional hydrogen bonds between polysaccharides in starch and PH. An increase in the number of hydrophilic groups in the modified films resulted in a faster contact angle decrease (27.4% compared to 12.8% for pure ones within the first 5 s); however, it increased the energy of water binding and surface complexity. The modified films showed the opacity at 600 nm, 43% higher than in the pure starch film, and lower transmittance, suggesting effectively improving barrier properties to UV light, a potent lipid-oxidizing agent in food systems.
Cement-Based Thermoelectric Device for Protection of Carbon Steel in Alkaline Chloride Solution
Authors: Ji Tao , Liao Xiao , Zhang Shiping , He Yan , Zhang Xiaoying , Zhang Xiong , Li Weihua
Published: June 2022

The thermoelectric cement-based materials can convert heat into electricity; this makes them promising candidates for impressed current cathodic protection of carbon steel. However, attempts to use the thermoelectric cement-based materials for energy conversion usually results in low conversion efficiency, because of the low electrical conductivity and Seebeck coefficient. Herein, we deposited polyaniline on the surface of MnO2 and fabricated a cement-based thermoelectric device with added PANI/MnO2 composite for the protection of carbon steel in alkaline chloride solution. The nanorod structure (70~80 nm in diameter) and evenly dispersed conductive PANI provide the PANI/MnO2 composite with good electrical conductivity (1.9 ± 0.03 S/cm) and Seebeck coefficient (−7.71 × 103 ± 50 μV/K) and, thereby, increase the Seebeck coefficient of cement-based materials to −2.02 × 103 ± 40 μV/K and the electrical conductivity of cement-based materials to 0.015 ± 0.0003 S/cm. Based on this, the corrosion of the carbon steel was delayed after cathodic protection, which was demonstrated by the electrochemical experiment results, such as the increased resistance of the carbon steel surface from 5.16 × 102 Ω·cm2 to 5.14 × 104 Ω·cm2, increased charge transfer resistance from 11.4 kΩ·cm2 to 1.98 × 106 kΩ·cm2, and the decreased corrosion current density from 1.67 μA/cm2 to 0.32 μA/cm2, underlining the role of anti-corrosion of the PANI/MnO2 composite in the cathodic protection system.
Modeling and Control of Layer Height in Laser Wire Additive Manufacturing
Authors: Mbodj Natago Guilé , Abuabiah Mohammad , Plapper Peter , El Kandaoui Maxime , Yaacoubi Slah
Published: June 2022

Laser Wire Additive Manufacturing (LWAM) is a flexible and fast manufacturing method used to produce variants of high metal geometric complexity. In this work, a physics-based model of the bead geometry including process parameters and material properties was developed for the LWAM process of large-scale products. The developed model aimed to include critical process parameters, material properties and thermal history to describe the relationship between the layer height with different process inputs (i.e., the power, the standoff distance, the temperature, the wire-feed rate, and the travel speed). Then, a Model Predictive Controller (MPC) was designed to keep the layer height trajectory constant taking into consideration the constraints faced in the LWAM technology. Experimental validation results were performed to check the accuracy of the proposed model and the results revealed that the developed model matches the experimental data. Finally, the designed MPC controller was able to track a predefined layer height reference signal by controlling the temperature input of the system.
Structure, Mechanical, and Micro-Scratch Behavior of Ta-Hf-C Solid Solution Coating Deposited by Non-Reactive Magnetron Sputtering
Authors: Tan Zhenyu , Wu Xiang , Yang Guo , Guo Jinwei , Zhu Wang
Published: June 2022

The TaC, HfC, and Hf-Ta-C coatings are successfully prepared by non-reactively DC magnetron sputtering. The effects of working pressure and deposition temperature on the structure and mechanical properties of Ta-Hf-C coating are analyzed. The scratch performance of the Ta-Hf-C coating deposited on 304 stainless steel and tungsten substrates are investigated. Results show the hardness and elastic modulus of Ta-Hf-C solid solution coating both increase to 37.8 ± 1.1 GPa and 435.8 ± 13.8 GPa due to the solid solution strengthening effect. Plastic deformation resistance H3/E2 of Ta-Hf-C coating can reach 0.285, which is more than twice that of binary coating. Furthermore, the scratch performance and failure mechanism show that Ta-Hf-C coating has a weaker plastic deformation resistance on soft substrate and low friction characteristic (0.01) on hard substrate, which implies that Ta-Hf-C coating is a good protective coating that can be applied to cutting tools.
Evaluation and Numerical Investigations of the Cyclic Behavior of Smart Composite Steel–Concrete Shear Wall: Comprehensive Study of Finite Element Model
Authors: Najm Hadee Mohammed , Ibrahim Amer M. , Sabri Mohanad Muayad Sabri , Hassan Amer , Morkhade Samadhan , Mashaan Nuha S. , Eldirderi Moutaz Mustafa A. , Khedher Khaled Mohamed
Published: June 2022

The composite shear wall has various merits over the traditional reinforced concrete walls. Thus, several experimental studies have been reported in the literature in order to study the seismic behavior of composite shear walls. However, few numerical investigations were found in the previous literature because of difficulties in the interaction behavior of steel and concrete. This study aimed to present a numerical analysis of smart composite shear walls, which use an infilled steel plate and concrete. The study was carried out using the ANSYS software. The mechanical mechanisms between the web plate and concrete were investigated thoroughly. The results obtained from the finite element (FE) analysis show excellent agreement with the experimental test results in terms of the hysteresis curves, failure behavior, ultimate strength, initial stiffness, and ductility. The present numerical investigations were focused on the effects of the gap, thickness of infill steel plate, thickness of the concrete wall, and distance between shear studs on the composite steel plate shear wall (CSPSW) behavior. The results indicate that increasing the gap between steel plate and concrete wall from 0 mm to 40 mm improved the stiffness by 18% as compared to the reference model, which led to delay failures of this model. Expanding the infill steel plate thickness to 12 mm enhanced the stiffness and energy absorption with a ratio of 95% and 58%, respectively. This resulted in a gradual drop in the strength capacity of this model. Meanwhile, increasing concrete wall thickness to 150 mm enhanced the ductility and energy absorption with a ratio of 52% and 32%, respectively, which led to restricting the model and reduced lateral offset. Changing the distance between shear studs from 20% to 25% enhanced the ductility and energy absorption by about 66% and 32%, respectively.
Dynamic Characteristic Analysis and Structural Optimization Design of the Large Mining Headframe
Authors: Liu Yue , Huang Min , An Qi , Bai Long , Shang Deyong
Published: June 2022

A large headframe is the core structure of a mine hoisting system. In the traditional design, only the static analysis under load is considered, resulting in the resonance phenomenon of the large headframe in later applications. In order to restrain the resonance phenomenon, a novel method for dynamic characteristic analysis and structural optimization design of a large headframe is proposed. First, the eigenfrequencies and vibration modes of the large headframe were obtained through modal analysis. The results showed that the numerical values of the multi-order eigenfrequencies of the system are relatively close. When subjected to alternating loads of similar frequencies, a large headframe is prone to the resonance phenomenon. Second, the steady-state vibration response of the large headframe was obtained through harmonic response analysis. The results showed that when the frequency of the alternating load is close to the first-order eigenfrequency, the vibration amplitude increases. Meanwhile, the fourth-order and the fifth-order eigenfrequencies are very close. When subjected to alternating loads of similar frequencies, the fourth-order and the fifth-order vibration modes of the headframe will be excited simultaneously. At this time, the headframe will have a strong resonance, which may cause structural damage and other problems. Finally, based on the above analysis, nine different structural optimization schemes are proposed in this paper. Through modal analysis and harmonic response analysis, the nine schemes were compared and analyzed, and the optimal scheme was eventually determined as scheme 9. The method proposed in this paper provides a new concept for the structural optimization design of a large mining headframe, and it has great significance for restraining the resonance phenomenon and ensuring the safety of mining operations.
Review on the Selection of Health Indicator for Lithium Ion Batteries
Authors: Zhou Wenlu , Lu Qiang , Zheng Yanping
Published: June 2022

Scientifically and accurately predicting the state of health (SOH) and remaining useful life (RUL) of batteries is the key technology of automotive battery management systems. The selection of the health indicator (HI) that characterizes battery aging affects the accuracy of the prediction model construction, which in turn affects the accuracy of SOH and RUL estimation. Therefore, this paper analyzes the current status of HI selection for lithium-ion batteries by systematically reviewing the existing literature on the selection of HIs. According to the relationship between HI and battery aging, battery HI can be divided into two categories: direct HI and indirect HI. The capacity and internal resistance of the battery can directly represent the aging degree of the battery and are the direct HIs of the battery. Indirect HIs refer to characteristic parameters extracted from battery charge and discharge data that can characterize the degree of battery aging. This paper analyzes and summarizes the advantages and disadvantages of various HIs and indirect HIs commonly used in current research, providing useful support and reference for future researchers in selecting HIs to characterize battery aging. Finally, in view of the capacity regeneration phenomenon in the aging process of the battery, the selection direction of future HI is proposed.
An Improved Pity Beetle Algorithm for Solving Constrained Engineering Design Problems
Authors: Peng Yu , Du Xianjun
Published: June 2022

To cope with increasingly complex models of engineering design problems and to obtain more accurate design solutions, this paper proposed an improved population-based, bio-inspired optimization algorithm, called the pity beetle algorithm based on pheromone dispersion model (PBA-PDM). PBA-PDM enables a local and global search for optimization problems through the pheromone release mechanisms in female beetles and the interaction relationship between male beetles. The experimental results compared with other state-of-the-art metaheuristic optimization algorithms show that PBA-PDM has an ideal performance when dealing with both classical test functions and CEC2017 benchmark test functions. Then, the PBA-PDM is applied in dealing with real-world constrained engineering design problems to verify the effectiveness and applicability. The above experimental results show that the PBA-PDM proposed in this paper is an effective and efficient algorithm for solving real-world optimization problems.
Novel Recurrence Relations for Volumes and Surfaces of n-Balls, Regular n-Simplices, and n-Orthoplices in Real Dimensions
Authors: Łukaszyk Szymon
Published: June 2022

This study examines n-balls, n-simplices, and n-orthoplices in real dimensions using novel recurrence relations that remove the indefiniteness present in known formulas. They show that in the negative, integer dimensions, the volumes of n-balls are zero if n is even, positive if n = −4k − 1, and negative if n = −4k − 3, for natural k. The volumes and surfaces of n-cubes inscribed in n-balls in negative dimensions are complex, wherein for negative, integer dimensions they are associated with integral powers of the imaginary unit. The relations are continuous for n ∈ ℝ and show that the constant of π is absent for 0 ≤ n < 2. For n < −1, self-dual n-simplices are undefined in the negative, integer dimensions, and their volumes and surfaces are imaginary in the negative, fractional ones and divergent with decreasing n. In the negative, integer dimensions, n-orthoplices reduce to the empty set, and their real volumes and imaginary surfaces are divergent in negative, fractional ones with decreasing n. Out of three regular, convex polytopes present in all natural dimensions, only n-orthoplices and n-cubes (and n-balls) are defined in the negative, integer dimensions.
Special Issue of Mathematics: Analytical and Numerical Methods for Linear and Nonlinear Analysis of Structures at Macro, Micro and Nano Scale
Authors: Żur Krzysztof Kamil , Kim Jinseok , Reddy Junuthula N.
Published: June 2022

The mathematical models of physical phenomena are based on the fundamental scientific laws of physics [...]
A Comprehensive Approach for an Approximative Integration of Nonlinear-Bivariate Functions in Mixed-Integer Linear Programming Models
Authors: Roth Maximilian , Franke Georg , Rinderknecht Stephan
Published: June 2022

As decentralized energy supply units, microgrids can make a decisive contribution to achieving climate targets. In this context, it is particularly important to determine the optimal size of the energy components contained in the microgrids and their optimal operating schedule. Hence, mathematical optimization methods are often used in association with such tasks. In particular, mixed-integer linear programming (MILP) has proven to be a useful tool. Due to the versatility of the different energetic components (e.g., storages, solar modules) and their special technical characteristics, linear relationships can often only inadequately describe the real processes. In order to take advantage of linear solution techniques but at the same time better represent these real-world processes, accurate and efficient approximation techniques need to be applied in system modeling. In particular, nonlinear-bivariate functions represent a major challenge, which is why this paper derives and implements a method that addresses this issue. The advantage of this method is that any bivariate mixed-integer nonlinear programming (MINLP) formulation can be transformed into a MILP formulation using this comprehensive method. For a performance comparison, a mixed-integer quadratic constrained programming (MIQCP) model—as an MINLP special case—is applied and transformed into a MILP, and the solution of the transformed problem is compared with the one of the MIQCP. Since there are good off-the-shelf solvers for MIQCP problems available, the comparison is conservative. The results for an exemplary microgrid sizing task show that the method delivers a strong performance, both in terms of approximation error (0.08%) and computation time. The method and its implementation can serve as a general user-tool but also as a basis for further methodological developments and research.
Learning Analytics and Computerized Formative Assessments: An Application of Dijkstra’s Shortest Path Algorithm for Personalized Test Scheduling
Authors: Bulut Okan , Shin Jinnie , Cormier Damien C.
Published: June 2022

The use of computerized formative assessments in K–12 classrooms has yielded valuable data that can be utilized by learning analytics (LA) systems to produce actionable insights for teachers and other school-based professionals. For example, LA systems utilizing computerized formative assessments can be used for monitoring students’ progress in reading and identifying struggling readers. Using such LA systems, teachers can also determine whether progress is adequate as the student works towards their instructional goal. However, due to the lack of guidelines on the timing, number, and frequency of computerized formative assessments, teachers often follow a one-size-fits-all approach by testing all students together on pre-determined dates. This approach leads to a rigid test scheduling that ignores the pace at which students improve their reading skills. In some cases, the consequence is testing that yields little to no useful data, while increasing the amount of instructional time that students miss. In this study, we propose an intelligent recommender system (IRS) based on Dijkstra’s shortest path algorithm that can produce an optimal assessment schedule for each student based on their reading progress throughout the school year. We demonstrated the feasibility of the IRS using real data from a large sample of students in grade two (n = 668,324) and grade four (n = 727,147) who participated in a series of computerized reading assessments. Also, we conducted a Monte Carlo simulation study to evaluate the performance of the IRS in the presence of unusual growth trajectories in reading (e.g., negative growth, no growth, and plateau). Our results showed that the IRS could reduce the number of test administrations required at both grade levels by eliminating test administrations in which students’ reading growth did not change substantially. In addition, the simulation results indicated that the IRS could yield robust results with meaningful recommendations under relatively extreme growth trajectories. Implications for the use of recommender systems in K–12 education and recommendations for future research are discussed.