bluuebunny/crossref_metadata_2025 huggingface dataset:
Autoimmune Neuroinflammatory Diseases: Role of Interleukins
Authors: Khan Abdul Waheed , Farooq Mariya , Hwang Moon-Jung , Haseeb Muhammad , Choi Sangdun
Published: April 2023

Autoimmune neuroinflammatory diseases are a group of disorders resulting from abnormal immune responses in the nervous system, causing inflammation and tissue damage. The interleukin (IL) family of cytokines, especially IL-1, IL-6, and IL-17, plays a critical role in the pathogenesis of these diseases. IL-1 is involved in the activation of immune cells, production of pro-inflammatory cytokines, and promotion of blood-brain barrier breakdown. IL-6 is essential for the differentiation of T cells into Th17 cells and has been implicated in the initiation and progression of neuroinflammation. IL-17 is a potent pro-inflammatory cytokine produced by Th17 cells that plays a crucial role in recruiting immune cells to sites of inflammation. This review summarizes the current understanding of the roles of different interleukins in autoimmune neuroinflammatory diseases, including multiple sclerosis, amyotrophic lateral sclerosis, Alzheimer’s disease, neuromyelitis optica, and autoimmune encephalitis, and discusses the potential of targeting ILs as a therapeutic strategy against these diseases. We also highlight the need for further research to better understand the roles of ILs in autoimmune neuroinflammatory diseases and to identify new targets for treating these debilitating diseases.
Improving Solubility and Permeability of Hesperidin through Electrospun Orange-Peel-Extract-Loaded Nanofibers
Authors: Paczkowska-Walendowska Magdalena , Miklaszewski Andrzej , Cielecka-Piontek Judyta
Published: April 2023

Orange peel, which is a rich source of polyphenolic compounds, including hesperidin, is produced as waste in production. Therefore, optimization of the extraction of hesperidin was performed to obtain its highest content. The influence of process parameters such as the kind of extraction mixture, its temperature and the number of repetitions of the cycles on hesperidin content, the total content of phenolic compounds and antioxidant (DPPH scavenging assay) as well as anti-inflammation activities (inhibition of hyaluronidase activity) was checked. Methanol and temperature were key parameters determining the efficiency of extraction in terms of the possibility of extracting compounds with the highest biological activity. The optimal parameters of the orange peel extraction process were 70% of methanol in the extraction mixture, a temperature of 70 °C and 4 cycles per 20 min. The second part of the work focuses on developing electrospinning technology to synthesize nanofibers of polyvinylpyrrolidone (PVP) and hydroxypropyl-β-cyclodextrin (HPβCD) loaded with hesperidin-rich orange peel extract. This is a response to the circumvention of restrictions in the use of hesperidin due to its poor bioavailability resulting from low solubility and permeability. Dissolution studies showed improved hesperidin solubility (over eight-fold), while the PAMPA-GIT assay confirmed significantly better transmucosal penetration (over nine-fold). A DPPH scavenging assay of antioxidant activity as well as inhibition of hyaluronidase to express anti-inflammation activity was established for hesperidin in prepared electrospun nanofibers, especially those based on HPβCD and PVP. Thus, hesperidin-rich orange peel nanofibers may have potential buccal applications to induce improved systemic effects with pro-health biological activity.
Staphylococcal Resistance Patterns, blaZ and SCCmec Cassette Genes in the Nasopharyngeal Microbiota of Pregnant Women
Authors: Andrzejczuk Sylwia , Cygan Monika , Dłuski Dominik , Stępień-Pyśniak Dagmara , Kosikowska Urszula
Published: April 2023

Antimicrobial resistance in Staphylococcus spp. colonising the nasopharynx can create risk factors of therapeutic treatment failure or prophylaxis in pregnant women. Resistance is mostly encoded on plasmids (e.g., blaZ gene for penicillinase synthesis) or chromosomes (e.g., mecA and mecC for methicillin resistance). The mecA gene is part of the chromosomal mec gene cassette (SCCmec), which is also located on the plasmid. The disc diffusion method for the selected drugs (beta-lactams, fluoroquinolones, streptogramins, aminoglicosides, macrolides, oxasolidinones, tetracyclines and other groups) was used. PCR for blaZ, mecA and mecC genes and SCCmec cassette detection and typing were performed. S. aureus (54.4%) and S. epidermidis (27.9%) were the most prevalent and showed the highest diversity of resistance profiles. The blaZ, mecA and mecC genes were reported in 95.6%, 20.6% and 1.5% of isolates, respectively. The highest resistance was found to beta-lactams, commonly used during pregnancy. Resistance to a variety of antimicrobials, including benzylpenicillin resistance in blaZ-positive isolates, and the existence of a very high diversity of SCCmec cassette structures in all staphylococci selected from the nasopharyngeal microbiota of pregnant women were observed for the first time. Knowledge of the prevalence of antimicrobial-resistant staphylococci in the nasopharynx of pregnant women may be important for the appropriate treatment or prophylaxis of this group of patients.
Peptaibol Analogs Show Potent Antibacterial Activity against Multidrug Resistant Opportunistic Pathogens
Authors: Dalla Torre Chiara , Sannio Filomena , Battistella Mattia , Docquier Jean-Denis , De Zotti Marta
Published: April 2023

New classes of antibacterial drugs are urgently needed to address the global issue of antibiotic resistance. In this context, peptaibols are promising membrane-active peptides since they are not involved in innate immunity and their antimicrobial activity does not involve specific cellular targets, therefore reducing the chance of bacterial resistance development. Trichogin GA IV is a nonhemolytic, natural, short-length peptaibol active against Gram-positive bacteria and resistant to proteolysis. In this work, we report on the antibacterial activity of cationic trichogin analogs. Several peptides appear non-hemolytic and strongly active against many clinically relevant bacterial species, including antibiotic-resistant clinical isolates, such as Staphylococcus aureus, Acinetobacter baumannii, and extensively drug-resistant Pseudomonas aeruginosa, against which there are only a limited number of antibiotics under development. Our results further highlight how the modification of natural peptides is a valuable strategy for obtaining improved antibacterial agents with potential therapeutic applications.
LncRNA NR_003508 Suppresses Mycobacterium tuberculosis-Induced Programmed Necrosis via Sponging miR-346-3p to Regulate RIPK1
Authors: Liu Li , Yu Zhirui , Ma Qinmei , Yu Jialin , Gong Zhaoqian , Deng Guangcun , Wu Xiaoling
Published: April 2023

Emerging evidence suggests that long non-coding RNAs (LncRNAs) are involved in Mtb-induced programmed necrosis. Among these LncRNAs, LncRNA NR_003508 is associated with LPS-induced acute respiratory distress syndrome. However, whether LncRNA NR_003508 contributes to Mtb-induced programmed necrosis remains undocumented. Firstly, the expression of LncRNA NR_003508 was determined using RT-qPCR and FISH. The protein expression of RIPK1, p-RIPK1, RIPK3, p-RIPK3, MLKL, and p-MLKL was measured by Western blot in RAW264.7 and mouse lung tissues. Furthermore, luciferase reporter assays and bioinformatics were used to predict specific miRNA (miR-346-3p) and mRNA (RIPK1) regulated by LncRNA NR_003508. In addition, RT-qPCR was used to detect the RIPK1 expression in TB patients and healthy peripheral blood. The flow cytometry assay was performed to detect cell necrosis rates. Here we show that BCG infection-induced cell necrosis and increased LncRNA NR_003508 expression. si-NR_003508 inhibited BCG/H37Rv-induced programmed necrosis in vitro or in vivo. Functionally, LncRNA NR_003508 has been verified as a ceRNA for absorbing miR-346-3p, which targets RIPK1. Moreover, RIPK1 expression was elevated in the peripheral blood of TB patients compared with healthy people. Knockdown of LncRNA NR_003508 or miR-346-3p overexpression suppresses cell necrosis rate and ROS accumulation in RAW264.7 cells. In conclusion, LncRNA NR_003508 functions as a positive regulator of Mtb-induced programmed necrosis via sponging miR-346-3p to regulate RIPK1. Our findings may provide a promising therapeutic target for tuberculosis.
Functional Characterization of Allelic Variations of Human Cytochrome P450 2C8 (V181I, I244V, I331T, and L361F)
Authors: Lee Yoo-Bin , Kim Vitchan , Lee Sung-Gyu , Lee Gyu-Hyeong , Kim Changmin , Jeong Eunseo , Kim Donghak
Published: April 2023

The human cytochrome P450 2C8 is responsible for the metabolism of various clinical drugs as well as endogenous fatty acids. Allelic variations can significantly influence the metabolic outcomes. In this study, we characterize the functional effects of four nonsynonymous single nucleotide polymorphisms *15, *16, *17, and *18 alleles recently identified in cytochrome P450 2C8. The recombinant allelic variant enzymes V181I, I244V, I331T, and L361F were successfully expressed in Escherichia coli and purified. The steady-state kinetic analysis of paclitaxel 6-hydroxylation revealed a significant reduction in the catalytic activities of the V181I, I244V, and L361F variants. The calculated catalytic efficiency (kcat/Km) of these variants was 5–26% of that of the wild-type enzyme. The reduced activities were due to both decreased kcat values and increased Km values of the variants. The epoxidation of arachidonic acid by the variants was analyzed. The L361F variant only exhibited 4–6% of the wild-type catalytic efficiency in ω-9- and ω-6-epoxidation reactions to produce 11,12-epoxyeicosatrienoic acid (EET) and 14,15-EET, respectively. These reductions were mainly due to a decrease in the kcat value of the L361F variant. The binding titration analysis of paclitaxel and arachidonic acid showed that all variants had similar affinities to those of the wild-type (10–14 μM for paclitaxel and 20–49 μM for arachidonic acid). The constructed paclitaxel docking model of the variant enzyme suggests that the L361F substitution leads to the incorrect orientation of paclitaxel in the active site, with the 6′C of paclitaxel displaced from the productive catalytic location. This study suggests that individuals carrying the newly identified P450 2C8 allelic variations are likely to have an altered metabolism of clinical medicines and production of fatty acid-derived signal molecules.
Na+ Lattice Doping Induces Oxygen Vacancies to Achieve High Capacity and Mitigate Voltage Decay of Li-Rich Cathodes
Authors: Qiu Hengrui , Zhang Rui , Zhang Youxiang
Published: April 2023

In this work, we synthesized 1D hollow square rod-shaped MnO2, and then obtained Na+ lattice doped-oxygen vacancy lithium-rich layered oxide by a simple molten salt template strategy. Different from the traditional synthesis method, the hollow square rod-shaped MnO2 in NaCl molten salt provides numerous anchor points for Li, Co, and Ni ions to directly prepare Li1.2Ni0.13Co0.13Mn0.54O2 on the original morphology. Meanwhile, Na+ is also introduced for lattice doping and induces the formation of oxygen vacancy. Therefrom, the modulated sample not only inherits the 1D rod-like morphology but also achieves Na+ lattice doping and oxygen vacancy endowment, which facilitates Li+ diffusion and improves the structural stability of the material. To this end, transmission electron microscopy, high-angle annular dark-field scanning transmission electron microscopy, X-ray photoelectron spectroscopy, and other characterization are used for analysis. In addition, density functional theory is used to further analyze the influence of oxygen vacancy generation on local transition metal ions, and theoretically explain the mechanism of the electrochemical performance of the samples. Therefore, the modulated sample has a high discharge capacity of 282 mAh g−1 and a high capacity retention of 90.02% after 150 cycles. At the same time, the voltage decay per cycle is only 0.0028 V, which is much lower than that of the material (0.0038 V per cycle) prepared without this strategy. In summary, a simple synthesis strategy is proposed, which can realize the morphology control of Li1.2Ni0.13Co0.13Mn0.54O2, doping of Na+ lattice, and inducing the formation of oxygen vacancy, providing a feasible idea for related exploration.
Association between PAI-1 Polymorphisms and Ischemic Stroke in a South Korean Case-Control Cohort
Authors: Choi Gun Ho , Cho Sung Hwan , An Hui Jeong , Park Han Sung , Lee Jeong Yong , Ko Eun Ju , Oh Seung Hun , Kim Ok Joon , Kim Nam Keun
Published: April 2023

Stroke is the second leading cause of death in the world. Approximately 80% of strokes are ischemic in origin. Many risk factors have been linked to stroke, including an increased level of plasminogen activator inhibitor-1 (PAI-1). PAI-1 levels increase and remain elevated in blood during the acute phase of ischemic stroke, which can impair fibrinolytic activity, leading to coronary artery disease and arterial thrombotic disorders. Here, we present a case-control study of 574 stroke patients and 425 controls seen for routine health examination or treatment for nonspecific dizziness, nonorganic headache, or anxiety for positive family history of stroke at the Bundang Medical Center in South Korea. Polymorphisms in PAI-1 were identified by polymerase chain reaction/restriction fragment length polymorphism analysis using genomic DNA. Specifically, three variations (−675 4G>5G, 10692T>C, and 12068G>A) were linked to a higher overall prevalence of stroke as well as a higher prevalence of certain stroke subtypes. Haplotype analyses also revealed combinations of these variations (−844G>A, −675 4G>5G, 43G>A, 9785A>G, 10692T>C, 11053T>G, and 12068G>A) that were significantly associated with a higher prevalence of ischemic stroke. To the best of our knowledge, this is the first strong evidence that polymorphic sites in PAI-1 promoter and 3′-UTR regions are associated with higher ischemic stroke risk. Furthermore, the PAI-1 genotypes and haplotypes identified here have potential as clinical biomarkers of ischemic stroke and could improve the prognosis and future management of stroke patients.
Critical Roles of the Cysteine–Glutathione Axis in the Production of γ-Glutamyl Peptides in the Nervous System
Authors: Fujii Junichi , Osaki Tsukasa , Soma Yuya , Matsuda Yumi
Published: April 2023

γ-Glutamyl moiety that is attached to the cysteine (Cys) residue in glutathione (GSH) protects it from peptidase-mediated degradation. The sulfhydryl group of the Cys residue represents most of the functions of GSH, which include electron donation to peroxidases, protection of reactive sulfhydryl in proteins via glutaredoxin, and glutathione conjugation of xenobiotics, whereas Cys-derived sulfur is also a pivotal component of some redox-responsive molecules. The amount of Cys that is available tends to restrict the capacity of GSH synthesis. In in vitro systems, cystine is the major form in the extracellular milieu, and a specific cystine transporter, xCT, is essential for survival in most lines of cells and in many primary cultivated cells as well. A reduction in the supply of Cys causes GPX4 to be inhibited due to insufficient GSH synthesis, which leads to iron-dependent necrotic cell death, ferroptosis. Cells generally cannot take up GSH without the removal of γ-glutamyl moiety by γ-glutamyl transferase (GGT) on the cell surface. Meanwhile, the Cys–GSH axis is essentially common to certain types of cells; primarily, neuronal cells that contain a unique metabolic system for intercellular communication concerning γ-glutamyl peptides. After a general description of metabolic processes concerning the Cys–GSH axis, we provide an overview and discuss the significance of GSH-related compounds in the nervous system.
Decomposed Two-Stage Prompt Learning for Few-Shot Named Entity Recognition
Authors: Ye Feiyang , Huang Liang , Liang Senjie , Chi KaiKai
Published: April 2023

Named entity recognition (NER) in a few-shot setting is an extremely challenging task, and most existing methods fail to account for the gap between NER tasks and pre-trained language models. Although prompt learning has been successfully applied in few-shot classification tasks, adapting to token-level classification similar to the NER task presents challenges in terms of time consumption and efficiency. In this work, we propose a decomposed prompt learning NER framework for few-shot settings, decomposing the NER task into two stages: entity locating and entity typing. In training, the location information of distant labels is used to train the entity locating model. A concise but effective prompt template is built to train the entity typing model. In inference, a pipeline approach is used to handle the entire NER task, which elegantly resolves time-consuming and inefficient problems. Specifically, a well-trained entity locating model is used to predict entity spans for each input. The input is then transformed using prompt templates, and the well-trained entity typing model is used to predict their types in a single step. Experimental results demonstrate that our framework outperforms previous prompt-based methods by an average of 2.3–12.9% in F1 score while achieving the best trade-off between accuracy and inference speed.
Host Specificity in Canopy Nesting Forms of Ochrogaster lunifer: The Larger Children Do Not Care
Authors: Farrell Julianne , Zalucki Myron P. , Battisti Andrea
Published: April 2023

The ‘mother knows best’ hypothesis is tested in a species of processionary moth feeding on acacias and eucalypts in Australia. The processionary moth Ochrogaster lunifer (Lepidoptera: Notodontidae; Thaumetopoeinae) is a social caterpillar living in large colonies on a number of tree and shrub species. Five nesting types—canopy, trunk, tree-hugger, hanging, and ground—have been described, and this study deals with canopy nesters on various species of acacias (Acacia spp.) and eucalypts (Eucalyptus spp. and Corymbia spp.). Reciprocal transplant experiments conducted over three years confirm the ‘mother knows best’ hypothesis, as colonies performed better on the natal host plant than on the recipient ones. Young first instar larvae were less likely to establish on a non-natal host than the mature larvae, and all acacia-sourced canopy egg masses failed to establish on eucalypts. Large larvae were able to establish on transplant hosts. This suggests a strong preference–performance link at what is likely a species level, confirming preliminary results recently published on genetic divergence. Canopy nesting forms also have a lower realised fecundity than the ground nesting form on acacias from the same geographic area, but higher than another canopy nesting form from western Australia. Further observations on ecological and genetic traits are required to draw conclusions about the separation of lineages in the canopy nesting form of O. lunifer, by including populations from other parts of the range for both the herbivore and the host plants.
Functional Clustering of Metabolically Related Genes Is Conserved across Dikarya
Authors: Cittadino Gina M. , Andrews Johnathan , Purewal Harpreet , Estanislao Acuña Avila Pedro , Arnone James T.
Published: April 2023

Transcriptional regulation is vital for organismal survival, with many layers and mechanisms collaborating to balance gene expression. One layer of this regulation is genome organization, specifically the clustering of functionally related, co-expressed genes along the chromosomes. Spatial organization allows for position effects to stabilize RNA expression and balance transcription, which can be advantageous for a number of reasons, including reductions in stochastic influences between the gene products. The organization of co-regulated gene families into functional clusters occurs extensively in Ascomycota fungi. However, this is less characterized within the related Basidiomycota fungi despite the many uses and applications for the species within this clade. This review will provide insight into the prevalence, purpose, and significance of the clustering of functionally related genes across Dikarya, including foundational studies from Ascomycetes and the current state of our understanding throughout representative Basidiomycete species.
Ethnomedicinal Use, Phytochemistry, Pharmacology, and Toxicology of Euphorbia resinifera O. Berg. (B): A Review
Authors: Hmidouche Oumaima , Bouftini Khadija , Chafik Abdelbasset , Khouri Sara , Rchid Halima , Rahimi Abdessadek , Mimouni Mostafa , Maarouf Elbekay , Zaakour Fatna , Nmila Rachid , Khouchlaa Aya
Published: April 2023

Euphorbia resinifera (Zaggûm or Tikiut) is an endemic species of Morocco that grows in the Middle Atlas Mountain range. It is used in folk medicine to treat several diseases, especially various types of cancer. Aim of the review: In this review, we critically highlighted and discussed previous reports on E. resinifera, concerning its botanical description, taxonomy, geographical distribution, and medicinal use. In addition, bioactive compounds, toxicology, and pharmacological effects were reported. Materials and methods: We searched various scientific databases, such as Scopus, PubMed, Web of Science, SpringerLink, SciFinder, Wiley Online, and Google Scholar, to collect data on E. resinifera. Studies involving E. resinifera or its bioactive compounds with regards to antitumor, anti-inflammatory, antileishmanial, antiprotease, immunomodulatory, irritant, and lysosomal activities are discussed here. Results: E. resinifera has been widely used in folk medicine practice in Morocco to treat several diseases such as diabetes, cancer, and inflammatory skin conditions, as well as to heal wounds. In phytochemistry studies, biochemical compounds have been identified from E. resinifera belonging specially to terpenoids. Indeed, in vitro and in vivo pharmacological investigations showed that extracts and compounds from the latex of E. resinifera exhibited a wide spectrum of biological properties, particularly antioxidant, antimicrobial, antitumor, anti-inflammatory, antileishmanial, and immunomodulatory and neuroprotective activities. Conclusion: The use of E. resinifera in conventional medicine is supported by processes founded on biological evidence. However, in-depth research is necessary to prove the safety and efficacy of E. resinifera latex extracts and their compounds and to clarify their pharmacological mechanisms. In addition, pharmacokinetic and pharmacodynamics studies are required for extracts and bioactive compounds.
DoE Approach to Setting Input Parameters for Digital 3D Printing of Concrete for Coarse Aggregates up to 8 mm
Authors: Vespalec Arnošt , Podroužek Jan , Koutný Daniel
Published: April 2023

This paper is primarily concerned with determining and assessing the properties of a cement-based composite material containing large particles of aggregate in digital manufacturing. The motivation is that mixtures with larger aggregate sizes offer benefits such as increased resistance to cracking, savings in other material components (such as Portland cement), and ultimately cost savings. Consequently, in the context of 3D Construction/Concrete Print technology (3DCP), these materials are environmentally friendly, unlike the fine-grained mixtures previously utilized. Prior to printing, these limits must be established within the virtual environment’s process parameters in order to reduce the amount of waste produced. This study extends the existing research in the field of large-scale 3DCP by employing coarse aggregate (crushed coarse river stone) with a maximum particle size of 8 mm. The research focuses on inverse material characterization, with the primary goal of determining the optimal combination of three monitored process parameters—print speed, extrusion height, and extrusion width—that will maximize buildability. Design Of Experiment was used to cover all possible variations and reduce the number of required simulations. In particular, the Box—Behnken method was used for three factors and a central point. As a result, thirteen combinations of process parameters covering the area of interest were determined. Thirteen numerical simulations were conducted using the Abaqus software, and the outcomes were discussed.
Structure and Wear Resistance of TiC-Reinforced Al1.8CrCuFeNi2 High-Entropy Alloy Coating Using Laser Cladding
Authors: Guo Jing , Liu Chenghao , Wang Dexing , Xu Lingfeng , Song Kaikai , Gao Ming
Published: April 2023

Al1.8CrCuFeNi2 high-entropy alloy coatings with different TiC contents were prepared using laser cladding. The effect of TiC on the microstructure, hardness and wear resistance of the coatings was investigated. It was found that the phase structure of the coating with 10 wt.% TiC was a single BCC phase with no other precipitated phase. When 20 wt.% TiC was added, the phase structure of the coating was a BCC phase and TiC phase. When the TiC content increased to 30 wt.%, more TiC-reinforcing phase was formed. With the increase in the TiC content, the hardness of the high-entropy alloy coating was enhanced and the wear loss clearly decreased, which was closely related to the change in the coating structure. The addition of TiC to high-entropy alloys plays the role of fine-grain strengthening and dispersion strengthening.
Luminescence Characteristics of the MOCVD GaN Structures with Chemically Etched Surfaces
Authors: Ceponis Tomas , Pavlov Jevgenij , Kadys Arunas , Vaitkevicius Augustas , Gaubas Eugenijus
Published: April 2023

Gallium nitride is a wide-direct-bandgap semiconductor suitable for the creation of modern optoelectronic devices and radiation tolerant detectors. However, formation of dislocations is inevitable in MOCVD GaN materials. Dislocations serve as accumulators of point defects within space charge regions covering cores of dislocations. Space charge regions also may act as local volumes of enhanced non-radiative recombination, deteriorating the photoluminescence efficiency. Surface etching has appeared to be an efficient means to increase the photoluminescence yield from MOCVD GaN materials. This work aimed to improve the scintillation characteristics of MOCVD GaN by a wet etching method. An additional blue photo-luminescence (B-PL) band peaking at 2.7–2.9 eV and related to dislocations was discovered. This B-PL band intensity appeared to be dependent on wet etching exposure. The intensity of the B-PL was considerably enhanced when recorded at rather low temperatures. This finding resembles PL thermal quenching of B-PL centers. The mechanisms of scintillation intensity and spectrum variations were examined by coordinating the complementary photo-ionization and PL spectroscopy techniques. Analysis of dislocation etch pits was additionally performed by scanning techniques, such as confocal and atomic force microscopy. It was proved that this blue luminescence band, which peaked at 2.7–2.9 eV, is related to point defects those decorate dislocation cores. It was shown that the intensity of this blue PL band was increased due to enhancement of light extraction efficiency, dependent on the surface area of either single etch-pit or total etched crystal surface.
Magnetic Properties of 2D Nanowire Arrays: Computer Simulations
Authors: Belim Sergey V. , Bychkov Igor V.
Published: April 2023

The paper considers a nanowires 2D array located in the nodes of a square lattice. Computer simulations use the Heisenberg model and Metropolis algorithm. The array consists of small nanowires that are monodomain. The exchange interaction orders the spins within a single nanowire. Dipole–dipole forces act between neighboring nanowires. The shape of an individual nanowire affects its magnetic anisotropy. Computer simulations examine the phase transition temperature and magnetization behavior of the system. The type of magnetic moments ordering in the array of nanowires depends on the orientation of their long axis. We consider two types of systems. The nanowires’ long axes are oriented perpendicular to the plane of their location in the first case. A dipole–dipole interaction results in first-type superantiferromagnetic ordering of the nanowires’ magnetic moments for such orientation. The nanowires’ long axes are oriented in the plane of the system in the second case. Dipole–dipole interaction results in second-type superantiferromagnetic ordering in such systems. The dependence of the phase transition temperature on the dipole–dipole interaction intensity is investigated.
Insights into the Synthesis Parameters Effects on the Structural, Morphological, and Magnetic Properties of Copper Oxide Nanoparticles
Authors: Mbarek Fatma , Chérif Ichraf , Chérif Amira , Alonso José María , Morales Irene , de la Presa Patricia , Ammar Salah
Published: April 2023

The present study aims at the integration of the “oxalic conversion” route into “green chemistry” for the synthesis of copper oxide nanoparticles (CuO-NPs) with controllable structural, morphological, and magnetic properties. Two oxalate-containing precursors (H2C2O4.2H2O and (NH4)2C2O4.H2O) and different volume ratios of a mixed water/glycerol solvent were tested. First, the copper oxalates were synthesized and then subjected to thermal decomposition in air at 400 °C to produce the CuO powders. The purity of the samples was confirmed by X-ray powder diffraction (XRPD), and the crystallite sizes were calculated using the Scherrer method. The transmission electron microscopy (TEM) images revealed oval-shaped CuO-NPs, and the scanning electron microscopy (SEM) showed that morphological features of copper oxalate precursors and their corresponding oxides were affected by the glycerol (V/V) ratio as well as the type of C2O42− starting material. The magnetic properties of CuO-NPs were determined by measuring the temperature-dependent magnetization and the hysteresis curves at 5 and 300 K. The obtained results indicate the simultaneous coexistence of dominant antiferromagnetic and weak ferromagnetic behavior.
Expanding the “Magic Triangle” of Reinforced Rubber Using a Supramolecular Filler Strategy
Authors: Zhao Yihong , Ren Mingwei , Zhu Xiangdong , Ren Zhangyu , Hu Yaofang , Zhao Huhu , Wang Weiheng , Chen Yunbo , Gao Kewei , Zhou Yujing
Published: April 2023

A strategy for optimizing the rolling resistance, wet skid and cut resistance of reinforced rubber simultaneously using a supramolecular filler is demonstrated. A β-alanine trimer-grafted Styrene Butadiene Rubber (A3-SBR) pristine polymer was designed and mechanically mixed with commercially available styrene butadiene rubber to help the dispersion of a β-alanine trimer (A3) supramolecular filler in the rubber matrix. To increase the miscibility of A3-SBR with other rubber components during mechanical mixing, the pristine polymer was saturated with ethanol before mixing. The mixture was vulcanized using a conventional rubber processing method. The morphology of the assembles of the A3 supramolecular filler in the rubber matrix was studied by Differential Scanning Calorimetry (DSC) and Transmission Electron Microscopy (TEM). The Differential Scanning Calorimetry study showed that the melting temperature of β-sheet crystals in the vulcanizates was around 179 °C and was broad. The melting temperature was similar to that of the pristine polymer, and the broad melting peak likely suggests that the size of the crystals is not uniform. The Transmission Electron Microscopy study revealed that after mixing the pristine polymer with SBR, some β-sheet crystals were rod-like with several tens of nanometers and some β-sheet crystals were particulate with low aspect ratios. Tensile testing with pre-cut specimens showed that the vulcanizate containing A3-SBR was more cut-resistant than the one that did not contain A3-SBR, especially at a large cut size. The rolling resistance and wet skid were predicted by dynamic mechanical analysis (DMA). DMA tests showed that the vulcanizates containing A3-SBR were significantly less hysteretic at 60 °C and more hysteretic at 0 °C based on loss factor. Overall, the “magic triangle” was expanded by optimizing the rolling resistance, wet-skid, and cut resistance simultaneously using a β-alanine trimer supramolecular filler. The Payne effect also became less severe after introducing the β-alanine trimer supramolecular filler into the system.
Experimental Investigation of Engine Valve Train Friction Considering Effects of Operating Conditions and WPC Surface Treatment
Authors: Bhutta Muhammad Usman , Najeeb Muhammad Huzaifa , Abdullah Muhammad Usman , Shah Samiur Rahman , Khurram Muhammad , Mufti Riaz Ahmad , Ogawa Kiyotaka , Aslam Jawad , Zahid Rehan , Ali Mian Ashfaq , Arshad Muazzam
Published: April 2023

Reduction in friction ensures fuel economy, control on emissions and durability of components in internal combustion engines. A modern gasoline internal combustion engine was instrumented to determine the friction values at the cam–roller interface considering the effects of surface treatment and engine operating state. A series of tests under different operating speeds and lubricant inlet temperatures were undertaken using both an original surface roller and a Wonder Process Craft (WPC) surface-treated engine roller. The results clearly revealed a substantial reduction in friction magnitude for the WPC surface-treated engine roller in comparison to the original roller while operating under similar conditions, indicating their strong potential for employment in engines. An increase in friction with the rise in temperature was also observed for both types of rollers, whereas increased lubricant entraining velocity due to higher operating speed had the opposite impact. A considerable reduction in frictional drive torque ranging from 8% to 28% was observed by employing the WPC-treated roller in comparison to original/untreated roller at various operating conditions, which signifies the strong potential for employment of WPC surface treatment in the roller/follower valve train engines.
Stress–Charge Nonlinear Physical Description and Tensor Symmetries for Piezoelectric Materials
Authors: Jaramillo-Alvarado A. F. , Torres Jacome A. , Rosales-Quintero P. , Vazquez-Leal H. , Diaz-Arango G. , Huerta-Chua J. , Martínez-Castillo J.
Published: April 2023

Nonlinear piezoelectric materials are raised as a great replacement for devices that require low power consumption, high sensitivity, and accurate transduction, fitting with the demanding requirements of new technologies such as the Fifth-Generation of telecommunications (5G), the Internet of Things (IoT), and modern radio frequency (RF) applications. In this work, the state equations that correctly predict the nonlinear piezoelectric phenomena observed experimentally are presented. Furthermore, we developed a fast methodology to implement the state equations in the main FEM simulation software, allowing an easy design and characterization of this type of device, as the symmetry structures for high-order tensors are shown and explained. The operation regime of each high-order tensor is discussed and connected with the main nonlinear phenomena reported in the literature. Finally, to demonstrate our theoretical deductions, we used the experimental measurements, which presented the nonlinear effects, which were reproduced through simulations, obtaining maximum percent errors for the effective elasticity constants, relative effective permittivity, and resonance frequencies of 0.79%, 2.9%, and 0.3%, respectively, giving a proof of the potential of the nonlinear state equations presented for the unifying of all nonlinear phenomena observed in the piezoelectric devices.
Investigation on Adsorption of Polar Molecules in Vegetable Insulating Oil by Functional Fossil Graphene
Authors: Liang Suning , Yang Zhi , Shao Xianjun , Zheng Yiming , Wang Qiang , Huang Zhengyong
Published: April 2023

As a new engineering dielectric, vegetable insulating oil is widely used in electrical equipment. Small polar molecules such as alcohol and acid will be produced during the oil-immersed electrical equipment operation, which seriously affects the safety of equipment. The polar molecule can be removed by using functional fossil graphene materials. However, the structural design and group modification of graphene materials lack a theoretical basis. Therefore, in this paper, molecular dynamics (MD) and quantum mechanics theory (Dmol3) were utilized to study the adsorption kinetics and mechanism of graphene (GE), porous graphene (PGE), porous hydroxy graphene (HPGE), and porous graphene modified by hydroxyl and carboxyl groups (COOH-HPGE) on polar small molecules in vegetable oil. The results show that graphene-based materials can effectively adsorb polar small molecules in vegetable oil, and that the modification of graphene materials with carboxyl and hydroxyl groups improves their adsorption ability for polar small molecules, which is attributed to the conversion of physical adsorption to chemical adsorption by the modification of oxygen-containing groups. This study provides a theoretical basis for the design and preparation of graphene materials with high adsorption properties.
Study on Carbon Fixation Ratio and Properties of Foamed Concrete
Authors: Wei Yuansheng , Cao Xiaoqiang , Wang Gang , Zhang Mingguang , Lv Zhiwen
Published: April 2023

Using solid waste to sequester carbon dioxide not only reduces the greenhouse effect but also reuses resources. However, the existing solidified carbon dioxide storage materials are expensive and have poor storage effect. Therefore, in this study, cement, solid waste base material, and 30% hydrogen peroxide were used to make foamed concrete materials through chemical foaming, and XRD, BET, SEM, and thermogravimetric techniques were used to explore the amount of carbon dioxide adsorbed by foamed concrete materials under different ratio conditions. The results show that (1) the hydration products of the cementified materials mainly include C-S-H, Ht and Ca(OH)2, which are important factors for the storage of CO2. (2) A water–cement ratio of 0.7 and a foaming agent dosage of 10% are the best ratios for foamed concrete materials. With the increase of the water–cement ratio and the dosage of the foaming agent, the amount of CO2-sealed stock first increases and then decreases. (3) The maximum carbon dioxide sealing capacity of foamed concrete material is 66.35 kg/m3.
Effect of Mineral Admixtures on the Mechanical and Shrinkage Performance of MgO Concrete
Authors: Zhou Xuan , Mao Zhongyang , Luo Penghui , Deng Min
Published: April 2023

Shrinkage deformation of concrete has been one of the difficulties in the process of concrete performance research. Cracking of concrete caused by self-shrinkage and temperature-drop shrinkage has become a common problem in the concrete world, and cracking leads to a decrease in the durability of concrete and even a safety hazard. Mineral admixtures, such as fly ash and mineral powder, are widely used to improve the temperature drop shrinkage of mass concrete; fly ash can reduce the temperature rise of concrete while also reducing the self-shrinkage of concrete, there are different results on the effect of mineral powder on the self-shrinkage of concrete, but the admixture of fly ash will reduce the strength of concrete, and mineral admixtures have an inhibitory effect on the shrinkage compensation effect of MgO expander(MEA). The paper investigates the effect of mineral admixtures on the mechanical and deformation properties of C50 mass concrete with a MgO expander(MEA), aiming to determine the proportion of C50 mass concrete with good anti-cracking properties under working conditions. The experiments investigated the effect of fly ash admixture, mineral powder admixture and MgO expander admixture on the compressive strength and deformation of concrete under simulated working conditions of variable temperature and analyzed the effect of hydration of magnesite in MgO expander and pore structure of cement paste on deformation. The following main conclusions were obtained: 1. When the concrete compounded with mineral admixture was cured under variable temperature conditions, the compounded 30% fly ash and mineral powder decreased by 4.3%, 6.0% and 8.4% at 7d age, and the compounded 40% fly ash and mineral powder decreased by 3.4%, 2.8% and 2.3% at 7d age, respectively. The incorporation of MEA reduced the early compressive strength of concrete; when the total amount of compounding remained unchanged, the early compressive strength of concrete was gradually smaller as the proportion of compounding decreased. 2. The results of concrete deformation showed that when the temperature rose, the concrete expanded rapidly, and when the temperature dropped, the concrete also showed a certain shrinkage, and the deformation of concrete basically reached stability at 18d. 3. The compounding of 30% fly ash and mineral powder As the compounding ratio decreases, the deformation of concrete increases, and the 28d deformation of concrete with a compounding ratio of 2:1 is 280 × 10−6, while the final stable deformation of concrete with a compounding ratio of 2:1 in compounding 40% fly ash and mineral powder is the largest, with a maximum value of 230 × 10−6, respectively. Overall, the concrete with a total compounding of 30% and a compounding ratio of 2:1 has the best shrinkage resistance performance.
Research and Application of High-Pressure Rotary Jet Method in the Seepage Treatment of Heavy Metal Tailing Ponds of Southwest China
Authors: Liang Mengjia , Jin Chunzheng , Hou Jiwu , Wang Mengyuan , Shi Yanping , Dong Zichao , Yang Xianyu , Zhou Jianwei , Cai Jihua
Published: April 2023

The developed karst caves may become the seepage channels of heavy metal to the soil and underground water in Southwest China. Therefore, it is necessary to apply effective seepage treatments to the base of heavy metal tailing reservoirs. This paper addressed the high-pressure rotary jet technology and slurry systems used in the seepage treatment of the deep tailing sand of the Shenxiandong tailing pond located in Southwest China. In this study, the factors of fluidity, initial and final setting times, compressive strength, and permeability coefficient of the slurry were conducted. The mechanism analysis was investigated by X-ray diffraction (XRD), scanning electron microscope (SEM), and inductively coupled plasma-mass spectrometry (ICP-MS). Three different types of slurry systems were proposed, and the permeability coefficients of the solidification body following 28 days of curing were less than 1 × 10−7 cm/s. The concentrations of Pb and Zn in the slurry system containing bentonite were reduced by 26.2% and 45.7%, respectively. In the presence of slaked lime and fly ash, the concentrations of Pb and Zn could be reduced by 26.8% and 30%, respectively. A total of 2142 high-pressure rotary jet piles were completed by the high-pressure rotary jet method in the field trial. The diffusion radius of these piles was over 1 m. Following 28 days of curing, the solidification body’s compressive strength was 7.45 MPa and the permeability coefficient was 6.27 × 10−8 cm/s. Both the laboratory and on-site trials showed that this method produced a good pollution barrier effect, which could prevent the diffusion of heavy metal into the adjacent underground water through the karst caves. It is also an effective way of engineering technology concerning heavy metal pollution control that occurs in tailing ponds.
Preparation of Densified Fine-Grain High-Frequency MnZn Ferrite Using the Cold Sintering Process
Authors: Ying Yao , Hu Linghuo , Li Zhaocheng , Zheng Jingwu , Yu Jing , Li Wangchang , Qiao Liang , Cai Wei , Li Juan , Bao Daxin , Che Shenglei
Published: April 2023

The densified MnZn ferrite ceramics were prepared using the cold sintering process under pressure, with an acetate ethanol solution used as the transient solvent. The effects of the transient solvent, the pressure and annealing temperature on the density, and the micromorphology and magnetic properties of the sintered MnZn ferrites were studied. The densified MnZn ferrite was obtained using the cold sintering process and its relative density reached up to 85.4%. The transient solvent and high pressure are essential to the cold sintering process for MnZn ferrite. The annealing treatment is indispensable in obtaining the sample with the higher density. The relative density was further increased to 97.2% for the sample annealed at 950 °C for 6 h. The increase in the annealing temperature reduces the power loss at high frequencies.
In Situ Grown 1D/2D Structure of Dy3Si2C2 on SiCw for Enhanced Electromagnetic Wave Absorption
Authors: Qin Gang , Li Yang , Zhou Wei , Xu Huidong , Hu Fang , Zhou Xiaobing
Published: April 2023

To improve electromagnetic wave (EMW) absorption performance, a novel nano-laminated Dy3Si2C2 coating was successfully in situ coated on the surface of SiC whisker (SiCw/Dy3Si2C2) using a molten salt approach. A labyrinthine three-dimensional (3D) net was constructed by the one-dimensional (1D) SiCw coated with the two-dimensional (2D) Dy3Si2C2 layer with a thickness of ~100 nm, which significantly improved the EMW absorption properties of SiCw. Compared to pure SiCw with the minimum reflection loss (RLmin) value of −10.64 dB and the effective absorption bandwidth (EAB) of 1.04 GHz for the sample with a thickness of 4.5 mm, SiCw/Dy3Si2C2 showed a significantly better EMW absorption performance with RLmin of −32.09 dB and wider EAB of 3.76 GHz for thinner samples with a thickness of 1.76 mm. The enhancement of the EMW absorption performance could be ascribed to the improvement of impedance matching, enhanced conductance loss, interfacial polarization as well as multiple scattering. The SiCw/Dy3Si2C2 can be a candidate for EMW absorber applications due to its excellent EMW absorption performance and wide EAB for relatively thin samples, light weight, as well as potential oxidation and corrosion resistance at high temperatures.
Experimental Investigations of the Dental Filling Materials: Establishing Elastic Moduli and Poisson’s Ratios
Authors: Száva Dániel Tamás , Száva Ioan , Vlase Sorin , Száva Andrea
Published: April 2023

The mechanical properties of the dental filling material (DFMs) strongly influence the lifetime and durability of the tooth reparation performed. Among the most significant mechanical characteristics, one has to mention the Poisson’s ratio and the elastic modulus (Young’s modulus). They, during the cyclic mastication load, can prevent or aid in the prevention of secondary dental decays by provoking micro-cracks, the de-bonding of the filling material from the natural dental tissue, as well as fatigue at the level of their interface. The authors performed a scoping analysis of the nowadays-involved experimental methods, together with a critical review, putting in evidence of their advantages and limits. Based on the developments, they propose a new approach in this sense by involving the electronic speckle pattern interferometry (ESPI)/shearography high-accuracy optical method. They illustrate the advantages of this method in establishment of the elastic modulus, but they also propose a high-accuracy methodology in the estimation of Poisson’s ratio. Based on the briefly-illustrated experimental results, one can conclude that ESPI/shearography can become a very useful tool for research, even though it is not a common (nowadays widely applied) method, such as three-point bending or strain gauge methods.