bluuebunny/crossref_metadata_2025 huggingface dataset:
Application of the Gradient-Boosting with Regression Trees to Predict the Coefficient of Friction on Drawbead in Sheet Metal Forming
Authors: Najm Sherwan Mohammed , Trzepieciński Tomasz , Laouini Salah Eddine , Kowalik Marek , Fejkiel Romuald , Kowalik Rafał
Published: September 2024

Correct design of the sheet metal forming process requires knowledge of the friction phenomenon occurring in various areas of the drawpiece. Additionally, the friction at the drawbead is decisive to ensure that the sheet flows in the desired direction. This article presents the results of experimental tests enabling the determination of the coefficient of friction at the drawbead and using a specially designed tribometer. The test material was a DC04 carbon steel sheet. The tests were carried out for different orientations of the samples in relation to the sheet rolling direction, different drawbead heights, different lubrication conditions and different average roughnesses of the countersamples. According to the aim of this work, the Features Importance analysis, conducted using the Gradient-Boosted Regression Trees algorithm, was used to find the influence of several parameter features on the coefficient of friction. The advantage of gradient-boosted decision trees is their ability to analyze complex relationships in the data and protect against overfitting. Another advantage is that there is no need for prior data processing. According to the best of the authors’ knowledge, the effectiveness of gradient-boosted decision trees in analyzing the friction occurring in the drawbead in sheet metal forming has not been previously studied. To improve the accuracy of the model, five MinLeafs were applied to the regression tree, together with 500 ensembles utilized for learning the previously learned nodes, noting that the MinLeaf indicates the minimum number of leaf node observations. The least-squares-boosting technique, often known as LSBoost, is used to train a group of regression trees. Features Importance analysis has shown that the friction conditions (dry friction of lubricated conditions) had the most significant influence on the coefficient of friction, at 56.98%, followed by the drawbead height, at 23.41%, and the sample width, at 11.95%. The average surface roughness of rollers and sample orientation have the smallest impact on the value of the coefficient of friction at 6.09% and 1.57%, respectively. The dispersion and deviation observed for the testing dataset from the experimental data indicate the model’s ability to predict the values of the coefficient of friction at a coefficient of determination of R2 = 0.972 and a mean-squared error of MSE = 0.000048. It was qualitatively found that in order to ensure the optimal (the lowest) coefficient of friction, it is necessary to control the friction conditions (use of lubricant) and the drawbead height.
Degree of Hydration, Microstructure, and Mechanical Properties of Cement-Modified TiO2 Nanoparticles
Authors: Choi Young-Cheol
Published: September 2024

This study investigated the effects of TiO2 nanoparticles (TNPs) on the hydration and microstructure of cement. The primary experimental variable was the TNP content, which ranged from 0 to 10 wt% of the cement. Cement paste and mortar specimens incorporating TNPs were prepared to assess the hydration characteristics, microstructure, and mechanical properties of the cement composites. Hydration characteristics were evaluated using heat of hydration, setting time, and thermogravimetric (TG) analysis. The microstructure was assessed through mercury intrusion porosimetry (MIP). The results indicated that TNPs accelerated the hydration of cement and modified the matrix microstructure, decreasing porosity and improving early-age strength. However, their tendency to agglomerate makes proper dispersion crucial for their effective application in construction materials. Therefore, when developing new building materials incorporating TNPs, it is essential to consider the properties of the nanoparticles and their physical and chemical effects on cement.
Investigations of Metallurgical Differences in AISI 347 and Their Influence on Deformation and Transformation Behaviour and Resulting Fatigue Life
Authors: Veile Georg , Regitz Elen , Smaga Marek , Weihe Stefan , Beck Tillmann
Published: September 2024

Due to variations in chemical composition and production processes, homonymous austenitic stainless steels can differ significantly regarding their initial microstructure, metastability, and thus, their fatigue behavior. Microstructural investigations and fatigue tests have been performed in order to evaluate this aspect. Three different batches and production forms of nominally one type of steel AISI 347 were investigated under monotonic tensile tests and cyclic loading under total strain and stress control in low and high cycle fatigue regimes, respectively. The deformation induced α’-martensite formation was investigated globally by means of in situ magnetic measurements and locally using optical light microscopy of color etching of micrographs. The investigation showed that the chemical composition and the different production processes influence the material behavior. In fatigue tests, a higher metastability and thus a higher level of deformation induced α’-martensite pronounced cyclic hardening, resulting in significantly greater endurable stresses in total strain-controlled tests and an increase in fatigue life in stress-controlled tests. For applications of non-destructive-testing, detailed knowledge of a component’s metastability is required. In less metastable batches and for lower stress levels, α’-martensite primarily formed at the plasticization zone of a crack. Furthermore, the formation and nucleation points of α’-martensite were highly dependent on grain size and the presence of δ-ferrite. This study provides valuable insights into the different material behavior of three different batches with the same designation, i.e., AISI 347, due to different manufacturing processes and differences in the chemical composition, metastability, and microstructure.
Mechanical Properties of Silicon Nitride in Different Morphologies: In Situ Experimental Analysis of Bulk and Whisker Structures
Authors: Wang Bokang , Bai Tanglong , Wang Weide , Zhang Hongti
Published: September 2024

Silicon nitride (Si3N4) is widely used in structural ceramics and advanced manufacturing due to its excellent mechanical properties and high-temperature stability. These applications always involve deformation under mechanical loads, necessitating a thorough understanding of their mechanical behavior and performance under load. However, the mechanical properties of Si3N4, particularly at the micro- and nanoscale, are not well understood. This study systematically investigated the mechanical properties of bulk Si3N4 and Si3N4 whiskers using in situ SEM indentation and uniaxial tensile strategies. First, nanoindentation tests on bulk Si3N4 at different contact depths ranging from 125 to 450 nm showed significant indentation size effect on modulus and hardness, presumably attributed to the strain gradient plasticity theory. Subsequently, in situ uniaxial tensile tests were performed on Si3N4 whiskers synthesized with two different sintering aids, MgSiN2 and Y2O3. The results indicated that whiskers sintered with Y2O3 exhibited higher modulus and strength compared to those sintered with MgSiN2. This work provides a deeper understanding of the mechanical behavior of Si3N4 at the micro- and nanoscale and offers guidance for the design of high-performance Si3N4 ceramic whiskers.
Incremental Growth Analysis of a Cantilever Beam under Cyclic Thermal and Axial Loads
Authors: Shahrjerdi Ali , Heydari Hamidreza , Bayat Mehdi , Shahzamanian Mohammadmehdi
Published: September 2024

Ratcheting analysis for cantilever beams subjected to the thermomechanical loads is presented using the finite element method. The cantilever beam is constrained along the vertical direction, and plane stress conditions are assumed according to the bilinear isotropic hardening model. Two points are considered to obtain areas of ratcheting by using linear extrapolation. The results and output diagrams for ratcheting with elastic-perfect plastic behavior are illustrated. It was revealed that the beam behaves elastically after the first considerable plastic strain, which is seen in two shakedown regimes. The numerical results are verified with known and analytical results in the literature. The results indicate a strong correlation between the outcomes from the cyclic ANSYS Parametric Design Language (APDL) model and Bree’s analytical predictions. This consistency between the finite element analysis and the analytical solutions underscores the potential of finite element analysis as a powerful tool for addressing complex engineering challenges, offering a reliable and robust alternative to traditional analytical methods.
Enhancing Mechanical Properties of Graphene/Aluminum Nanocomposites via Microstructure Design Using Molecular Dynamics Simulations
Authors: Ma Zhonglei , Wang Hongding , Zhao Yanlong , Li Zhengning , Liu Hong , Yang Yizhao , Zhao Zigeng
Published: September 2024

This study explores the mechanical properties of graphene/aluminum (Gr/Al) nanocomposites through nanoindentation testing performed via molecular dynamics simulations in a large-scale atomic/molecular massively parallel simulator (LAMMPS). The simulation model was initially subjected to energy minimization at 300 K, followed by relaxation for 50 ps under the NPT ensemble, wherein the number of atoms (N), simulation temperature (T), and pressure (P) were conserved. After the model was fully relaxed, loading and unloading simulations were performed. This study focused on the effects of the Gr arrangement with a brick-and-mortar structure and incorporation of high-entropy alloy (HEA) coatings on mechanical properties. The findings revealed that Gr sheets (GSs) significantly impeded dislocation propagation, preventing the dislocation network from penetrating the Gr layer within the plastic zone. However, interactions between dislocations and GSs in the Gr/Al nanocomposites resulted in reduced hardness compared with that of pure aluminum. After modifying the arrangement of GSs and introducing HEA (FeNiCrCoAl) coatings, the elastic modulus and hardness of the Gr/Al nanocomposites were 83 and 9.5 GPa, respectively, representing increases of 21.5% and 17.3% compared with those of pure aluminum. This study demonstrates that vertically oriented GSs in combination with HEA coatings at a mass fraction of 3.4% significantly enhance the mechanical properties of the Gr/Al nanocomposites.
A Domain Generation Diagnosis Framework for Unseen Conditions Based on Adaptive Feature Fusion and Augmentation
Authors: Zhang Tong , Chen Haowen , Mao Xianqun , Zhu Xin , Xu Lefei
Published: September 2024

Emerging deep learning-based fault diagnosis methods have advanced in the current industrial scenarios of various working conditions. However, the prerequisite of obtaining target data in advance limits the application of these models to practical engineering scenarios. To address the challenge of fault diagnosis under unseen working conditions, a domain generation framework for unseen conditions fault diagnosis is proposed, which consists of an Adaptive Feature Fusion Domain Generation Network (AFFN) and a Mix-up Augmentation Method (MAM) for both the data and domain spaces. AFFN is utilized to fuse domain-invariant and domain-specific representations to improve the model’s generalization performance. MAM enhances the model’s exploration ability for unseen domain boundaries. The diagnostic framework with AFFN and MAM can effectively learn more discriminative features from multiple source domains to perform different generalization tasks for unseen working loads and machines. The feasibility of the proposed unseen conditions diagnostic framework is validated on the SDUST and PU datasets and achieved peak diagnostic accuracies of 94.15% and 93.27%, respectively.
Learning Unsupervised Cross-Domain Model for TIR Target Tracking
Authors: Shu Xiu , Huang Feng , Qiu Zhaobing , Zhang Xinming , Yuan Di
Published: September 2024

The limited availability of thermal infrared (TIR) training samples leads to suboptimal target representation by convolutional feature extraction networks, which adversely impacts the accuracy of TIR target tracking methods. To address this issue, we propose an unsupervised cross-domain model (UCDT) for TIR tracking. Our approach leverages labeled training samples from the RGB domain (source domain) to train a general feature extraction network. We then employ a cross-domain model to adapt this network for effective target feature extraction in the TIR domain (target domain). This cross-domain strategy addresses the challenge of limited TIR training samples effectively. Additionally, we utilize an unsupervised learning technique to generate pseudo-labels for unlabeled training samples in the source domain, which helps overcome the limitations imposed by the scarcity of annotated training data. Extensive experiments demonstrate that our UCDT tracking method outperforms existing tracking approaches on the PTB-TIR and LSOTB-TIR benchmarks.
Enantioselectivity in Vanadium-Dependent Haloperoxidases of Different Marine Sources for Sulfide Oxidation to Sulfoxides
Authors: Zhang Yun-Han , Zou Ya-Ting , Zeng Yong-Yi , Liu Lan , Chen Bi-Shuang
Published: September 2024

This study explores the reasons behind the variations in the enantioselectivity of the sulfoxidation of methyl phenyl sulfide by marine-derived vanadium-dependent haloperoxidases (VHPOs). Twelve new VHPOs of marine organisms were overexpressed, purified, and tested for their ability to oxidize sulfide. Most of these marine enzymes exhibited nonenantioselective behavior, underscoring the uniqueness of AnVBPO from the brown seaweed Ascophyllum nodosum and CpVBPO from the red seaweed Corallina pilulifera, which produce (R)- and (S)-sulfoxides, respectively. The enantioselective sulfoxidation pathway is likely due to direct oxygen transfer within the VHPO active site. This was demonstrated through molecular docking and molecular dynamics simulations, which revealed differences in the positioning of sulfide within AnVBPO and CpVBPO, thus explaining their distinct enantioselectivities. Nonenantioselective VHPOs probably follow a different oxidation pathway, initiating with sulfide oxidation to form a positively charged radical. Further insights were gained from studying the catalytic effect of VO43− on H2O2-driven sulfoxidation. This research improves the understanding of VHPO-mediated sulfoxidation and aids in developing biocatalysts for sulfoxide synthesis.
Fermented Fish Collagen Attenuates Melanogenesis via Decreasing UV-Induced Oxidative Stress
Authors: Byun Kyung-A , Lee So Young , Oh Seyeon , Batsukh Sosorburam , Jang Jong-Won , Lee Bae-Jin , Rheu Kyoung-min , Li Sichao , Jeong Min-Seok , Son Kuk Hui , Byun Kyunghee
Published: September 2024

Excessive melanogenesis leads to hyperpigmentation-related cosmetic problems. UV exposure increases oxidative stress, which promotes melanogenesis-related signal pathways such as the PKA, microphthalmia-associated transcription factor (MITF), tyrosinase (TYR), tyrosinase-related protein-1 (TRP1), and tyrosinase-related protein-2 (TRP2) pathways. Glycine is a source of endogenous antioxidants, including glutathione. Fermented fish collagen (FC) contains glycine; thus, we evaluated the effect of FC on decreasing melanogenesis via decreasing oxidative stress. The glycine receptor (GlyR) and glycine transporter-1 (GlyT1) levels were decreased in UV-irradiated keratinocytes; however, the expression levels of these proteins increased upon treatment with FC. The FC decreased oxidative stress, as indicated by the decreasing expression of NOX1/2/4, increased expression of GSH/GSSG, increased SOD activity, and decreased 8-OHdG expression in UV-irradiated keratinocytes. Administration of conditioned media from FC-treated keratinocytes to melanocytes led to decreased p38, PKC, MITF, TRP1, and TRP2 expression. These changes induced by the FC were also observed in UV-irradiated animal skin. FC treatment increased the expression of GlyR and GlyT, which was accompanied by decreased oxidative stress in the UV-irradiated skin. Moreover, the FC negatively regulated the melanogenesis signaling pathways, leading to decreased melanin content in the UV-irradiated skin. In conclusion, FC decreased UV-induced oxidative stress and melanogenesis in melanocytes and animal skin. FC could be used in the treatment of UV-induced hyperpigmentation problems.
A Comprehensive Evaluation of Electrochemical Performance of Aluminum Hybrid Nanocomposites Reinforced with Alumina (Al2O3) and Graphene Oxide (GO)
Authors: Khan Muhammad Faizan , Mohammed Abdul Samad , Toor Ihsan-ul-Haq
Published: September 2024

The electrochemical performance of in-house developed, spark plasma-sintered, Aluminum metal–matrix composites (MMCs) was evaluated using different electrochemical techniques. X-ray diffraction (XRD) and Raman spectra were used to characterize the nanocomposites along with FE-SEM and EDS for morphological, structural, and elemental analysis, respectively. The highest charge transfer resistance (Rct), lowest corrosion current density, lowest electrochemical potential noise (EPN), and electrochemical current noise (ECN) were observed for GO-reinforced Al-MMC. The addition of honeycomb-like structure in the Al matrix assisted in blocking the diffusion of Cl− or SO4−2. However, poor wettability in between Al matrix and Al2O3 reinforcement resulted in the formation of porous interface regions, leading to a degradation in the corrosion resistance of the composite. Post-corrosion surface analysis by optical profilometer indicated that, unlike its counterparts, the lowest surface roughness (Ra) was provided by GO-reinforced MMC.
Improvement of Single Event Transient Effects for a Novel AlGaN/GaN High Electron-Mobility Transistor with a P-GaN Buried Layer and a Locally Doped Barrier Layer
Authors: Xiong Juan , Xie Xintong , Wei Jie , Sun Shuxiang , Luo Xiaorong
Published: September 2024

In this paper, a novel AlGaN/GaN HEMT structure with a P-GaN buried layer in the buffer layer and a locally doped barrier layer under the gate (PN-HEMT) is proposed to enhance its resistance to single event transient (SET) effects while also overcoming the degradation of other characteristics. The device operation mechanism and characteristics are investigated by TCAD simulation. The results show that the peak electric field and impact ionization at the gate edges are reduced in the PN-HEMT due to the introduced P-GaN buried layer in the buffer layer. This leads to a decrease in the peak drain current (Ipeak) induced by the SET effect and an improvement in the breakdown voltage (BV). Additionally, the locally doped barrier layer provides extra electrons to the channel, resulting in higher saturated drain current (ID,sat) and maximum transconductance (gmax). The Ipeak of the PN-HEMT (1.37 A/mm) is 71.8% lower than that of the conventional AlGaN/GaN HEMT (C-HEMT) (4.85 A/mm) at 0.6 pC/µm. Simultaneously, ID,sat and BV are increased by 21.2% and 63.9%, respectively. Therefore, the PN-HEMT enhances the hardened SET effect of the device without sacrificing other key characteristics of the AlGaN/GaN HEMT.
Treatment with Epigallocatechin Gallate, Folic Acid, Vitamin B12, and Hyaluronic Acid Decreases HPV Positivity in Women Attending Regional Screening in Puglia
Authors: Tinelli Andrea , Gustapane Sarah , Licchelli Martina , Coluccia Anna Chiara , Panese Gaetano , Proietti Sara , Gambioli Riccardo
Published: September 2024

Human Papillomavirus (HPV) infection represents a global health concern. HPV infects the mucosa, particularly in the uterine cervix, where it may establish a persistent infection, exposing women to a risk of developing cancer. The available treatments include surgery or topic solutions, while a systemic treatment is still unavailable. In recent years, natural molecules such as epigallocatechin gallate (EGCG), folic acid (FA), vitamin B12, and hyaluronic acid (HA) gained importance as innovative therapies for HPV. We enrolled 163 women with a positive HPV DNA test or previous history of HPV infections, and a PAP test indicating LSIL/AGUS/ASCUS cytology. The patients in the treatment group (n = 86) received an oral combination of EGCG 200 mg, FA 400 µg, vitamin B12 1 mg, and HA 50 mg (1 cps/day) for 3 months (T1), while the control group (n = 77) underwent standard clinical surveillance. Both groups repeated a PAP test and an HPV DNA test after 3 (T1) months, and another PAP test after 6 months (T2) as a follow up. The treatment group experienced a significant reduction in HPV positivity at T1 compared to the control group. Moreover, the treatment group exhibited an improvement in cervical lesions either at T1 (p < 0.0001) or T2 (p < 0.00001).
Distribution Characteristics of Nitrogen-Cycling Microorganisms in Deep-Sea Surface Sediments of Western South China Sea
Authors: Yin Xingjia , Chen Hui , Jiang Kaixi , Zhang Boda , Li Ruohong , Zhu Xinzhe , Sun Lianpeng , Ng Zhi Lin , Su Ming
Published: September 2024

Nitrogen-cycling processes in the deep sea remain understudied. This study investigates the distribution of nitrogen-cycling microbial communities in the deep-sea surface sediments of the western South China Sea, using metagenomic sequencing and real-time fluorescent quantitative PCR techniques to analyze their composition and abundance, and the effects of 11 environmental parameters, including NH4+-N, NO3−-N, NO2−-N, PO43−-P, total nitrogen (TN), total organic carbon (TOC), C/N ratio, pH, electrical conductivity (EC), SO42−, and Cl−. The phylum- and species-level microbial community compositions show that five sites can be grouped as a major cluster, with sites S1 and S9 forming a sub-cluster, and sites S13, S19, and S26 forming the other; whereas sites S3 and S5 constitute a separate cluster. This is also evident for nitrogen-cycling functional genes, where their abundance is influenced by distinct environmental conditions, including water depths (shallower at sites S1 and S9 against deeper at sites S13, S19, and S26) and unique geological features (sites S3 and S5), whereas the vertical distribution of nitrogen-cycling gene abundance generally shows a decreasing trend against sediment depth. Redundancy analysis (RDA) exploring the correlation between the 11 environmental parameters and microbial communities revealed that the NO2−-N, C/N ratio, and TN significantly affect microbial community composition (p < 0.05). This study assesses the survival strategies of microorganisms within deep-sea surface sediments and their role in the marine nitrogen cycle.
Physico-Chemical Properties and Chemical Analysis of Wildflower Honey Before and After the Addition of Spirulina (Arthrospira platensis)
Authors: Taiti Cosimo , Costantini Lara , Comparini Diego , Merendino Nicolò , Garzoli Stefania
Published: September 2024

In this study, in order to verify the effects due to the addition of spirulina (Arthrospira platensis) in a food product, a wildflower honey was analyzed in terms of chemical composition, physicochemical properties and antioxidant activity before and after the addition of the spirulina. HS-SPME/GC–MS and HPLC/UV were applied to carry out the chemical analyses. The obtained results demonstrated that the volatile profile and also the sugar content were significantly influenced by the addition of spirulina, showing significant qualitative and quantitative differences compared to honey without spirulina. The increase in HMF in honey added with spirulina was significant, demonstrating that its presence could accelerate the Maillard reaction. Electrical conductivity measured by using a conductometer was also increased while the moisture content was reduced in honey enriched with spirulina. Instead, the pH value was similar between the two samples. On the other hand, honey fortification with spirulina determined a significant increase of 12.5% in the total phenolic content (TPC), and a 56.25% increase in protein content. Further, the total antioxidant capacity (TAC) was also evaluated and a significant increase was determined as a result of the addition of spirulina. In conclusion, honey enriched with A. platensis was found to be characterized by a high pool of bioactive metabolites as well as significant changes in almost all the measurements performed.
Magnetic Resonance Imaging-Based Monitoring of the Accumulation of Polyethylene Terephthalate Nanoplastics
Authors: Bashirova Narmin , Butenschön Erik , Poppitz David , Gaß Henrik , Halik Marcus , Dentel Doreen , Tegenkamp Christoph , Matysik Joerg , Alia A.
Published: September 2024

Polyethylene terephthalate (PET) is one of the most produced plastic materials in the world. The emergence of microplastics and nanoplastics (MPs/NPs) as a significant environmental contaminant has become a matter of increasing concern. While the toxicological effects of PET NPs have been widely researched, there is a lack of methodologies for studying their accumulation. The present study introduces a novel method to monitor the distribution of PET NPs in germinating wheat (Triticum aestivum L.) seeds. This involves the functionalization of superparamagnetic iron oxide nanoparticles (SPIONs) with PET NPs (PET–fSPIONs) coupled with magnetic resonance microimaging (µMRI) to provide insight into their distribution within the seed. The present study has demonstrated that PET–fSPIONs accumulate in specific regions of germinating wheat seeds, including the shoot apical meristem, the radicle, the coleoptile, the plumule, and the scutellum. Furthermore, the accumulation of PET–fSPIONs has been shown to exert a discernible effect on spin–spin relaxation (T2), as observed via MRI and quantitative T2 relaxation time analysis. The accumulation of PET NPs in embryo regions was also confirmed by SEM. Diffusion-weighted magnetic resonance imaging (DW-MRI) and non-invasive chemical shift imaging analyses demonstrated that PET NPs resulted in restricted diffusion within the highlighted areas, as well as an impact on lipid content. Our study reveals that using µMRI with fSPIONs provides a non-invasive method to monitor the biodistribution of PET nanoparticles in wheat seeds. Additionally, it offers valuable insights into the microstructural interactions of PET.
A Silver Modified Nanosheet Self-Assembled Hollow Microsphere with Enhanced Conductivity and Permeability
Authors: Wang Fangmin , Dong Xue , Zhao Yuzhen , He Zemin , Song Wenqi , Li Chunsheng , Li Jiayin , Huang Jianfeng , Miao Zongcheng
Published: September 2024

The utilization of sheet structure composites as a viable conductive filler has been implemented in polymer-based electromagnetic shielding materials. However, the development of an innovative sheet structure to enhance electromagnetic shielding performance remains a significant challenge. Herein, we propose a novel design incorporating silver-modified nanosheet self-assembled hollow spheres to optimize their performance. The unique microporous structure of the hollow composite, combined with the self-assembled surface nanosheets, facilitates multiple reflections of electromagnetic waves, thereby enhancing the dissipation of electromagnetic energy. The contribution of absorbing and reflecting electromagnetic waves in hollow nanostructures could be attributed to both the inner and outer surfaces. When multiple reflection attenuation is implemented, the self-assembled stack structure of nanosheets outside the composite material significantly enhances the occurrence of multiple reflections, thereby effectively improving its shielding performance. The structure also facilitates multiple reflections of incoming electromagnetic waves at the internal and external interfaces of the material, thereby enhancing the shielding efficiency. Simultaneously, the incorporation of silver particles can enhance conductivity and further augment the shielding properties. Finally, the optimized Ag/NiSi-Ni nanocomposites can demonstrate superior initial permeability (2.1 × 10−6 H m−1), saturation magnetization (13.2 emu g−1), and conductivity (1.2 × 10−3 Ω•m). This work could offer insights for structural design of conductive fillers with improved electromagnetic shielding performance.
Density Functional Theory Prediction of Laser Dyes–Cucurbit[7]uril Binding Affinities
Authors: Petkova Vladislava , Dobrev Stefan , Kircheva Nikoleta , Nazarova Dimana , Nedelchev Lian , Nikolova Valya , Dudev Todor , Angelova Silvia
Published: September 2024

Among a variety of diverse host molecules distinguished by specific characteristics, the cucurbit[n]uril (CB) family stands out, being widely known for the attractive properties of its representatives along with their increasingly expanding area of applications. The presented herewith density functional theory (DFT)-based study is inspired by some recent studies exploring CBs as a key component in multifunctional hydrogels with applications in materials science, thus considering CB-assisted supramolecular polymeric hydrogels (CB-SPHs), a new class of 3D cross-linked polymer materials. The research systematically investigates the inclusion process between the most applied representative of the cavitand family CB[7] and a series of laser dye molecules as guests, as well as the possible encapsulation of a model side chain from the photoanisotropic polymer PAZO and its sodium-containing salt. The obtained results shed light on the most significant factors that play a key role in the recognition process, such as binding mode, charge, and dielectric constant of the solvent. The observed findings provide valuable insights at a molecular level for the design of dye–CB[7] systems in various environments, with potential applications in intriguing and prosperous fields like photonics and material science.
Study of the Effect of Cedar Sawdust Content on Physical and Mechanical Properties of Cement Boards
Authors: El Hamri Anas , Mouhib Yassine , Ourmiche Atmane , Chigr Mohammed , El Mansouri Nour-Eddine
Published: September 2024

The growing demand for sustainable building materials, amid escalating costs, has spurred interest in alternative solutions such as wood cement composites. This study explores the feasibility of producing wood cement boards (WCBs) using locally sourced cedar sawdust as a reinforcing agent. Boards with a thickness of 10 mm and a target density of 1200 kg/m3 were manufactured under pressures ranging from 2 to 6 MPa for 24 h. Cedar sawdust, used as raw and untreated material, was incorporated into the mixture as a partial substitute for cement in varying proportions, ranging from 10% to 25% (by weight). The WCBs were cured for 28 days under ambient conditions. Physical properties including density, water absorption (WA), and thickness swelling (TS) were assessed, along with mechanical properties through flexural tests. The results showed that increasing cedar sawdust content decreased both density and mechanical performance while increasing WA and TS. Microstructural analysis (SEM and EDS) revealed significant porosity at higher sawdust contents, while lower contents had better matrix–reinforcement cohesion. Additionally, substantial levels of calcium and silicon were detected on the sawdust surface, indicating stabilized cement hydration products. These findings, supported by thermal (TGA and DSC) and FTIR analyses, clearly demonstrate that cement boards with 10% cedar sawdust exhibit favorable properties for non-structural applications, such as wall and partition cladding.
Progress in the Study of Natural Antimicrobial Active Substances in Pseudomonas aeruginosa
Authors: Si Tianbo , Wang Anqi , Yan Haowen , Kong Lingcong , Guan Lili , He Chengguang , Ma Yiyi , Zhang Haipeng , Ma Hongxia
Published: September 2024

The prevalence of antimicrobial resistance reduces the effectiveness of antimicrobial drugs in the prevention and treatment of infectious diseases caused by pathogens such as bacteria, fungi, and viruses. Microbial secondary metabolites have been recognized as important sources for new drug discovery and development, yielding a wide range of structurally novel and functionally diverse antimicrobial drugs for the treatment of a variety of diseases that are considered good producers of novel antimicrobial drugs. Bacteria produce a wide variety of antimicrobial compounds, and thus, antibiotics derived from natural products still dominate over purely synthetic antibiotics among the antimicrobial drugs developed and introduced over the last four decades. Among them, Pseudomonas aeruginosa secondary metabolites constitute a richly diverse source of antimicrobial substances with good antimicrobial activity. Therefore, they are regarded as an outstanding resource for finding novel bioactive compounds. The exploration of antimicrobial compounds among Pseudomonas aeruginosa metabolites plays an important role in drug development and biomedical research. Reports on the secondary metabolites of Pseudomonas aeruginosa, many of which are of pharmacological importance, hold great promise for the development of effective antimicrobial drugs against microbial infections by drug-resistant pathogens. In this review, we attempt to summarize published articles from the last twenty-five years (2000–2024) on antimicrobial secondary metabolites from Pseudomonas aeruginosa.
Hydrogel Capacitors Based on MoS2 Nanosheets and Applications in Glucose Monitoring
Authors: Wang Yizhi , Zhang Jinwen , Zhang Yusen , Wang Bing , Zhang Yang , Lin Hui
Published: September 2024

Non-invasive/minimally invasive continuous monitoring of blood glucose and blood glucose administration have a high impact on chronic disease management in diabetic patients, but the existing technology is yet to achieve the above two purposes at the same time. Therefore, this study proposes a microfluidic microneedle patch based on 3D printing technology and an integrated control system design for blood glucose measurement, and a drug delivery control circuit based on a 555 chip. The proposed method provides an improved preparation of a PVA-PEG-MoS2 nanosheet hydrogel, making use of its dielectric properties to fabricate a microcapacitor and then embedding it in a microfluidic chip. When MoS2 nanosheets react with interstitial liquid glucose (and during the calibration process), the permittivity of the hydrogel is changed, resulting in changes in the capacitance of the capacitor. By converting the capacitance change into the square-wave period change in the output of the 555 chip with the control circuit design accordingly, the minimally invasive continuous measurement of blood glucose and the controlled release of hypoglycemic drugs are realized. In this study, the cross-linking structure of MoS2 nanosheets in hydrogel was examined using infrared spectroscopy and scanning electron microscopy (SEM) methods. Moreover, the critical doping mass fraction of MoS2 nanosheets was determined to be 2% via the measurement of the dielectric constant. Meanwhile, the circuit design and the relationship between the pulse cycle and glucose concentration is validated. The results show that, compared with capacitors in series, the microcapacitors embedded in microfluidic channels can be connected in parallel to obtain better linearized blood glucose measurement results.
Relationship between the Mediterranean Diet and Vascular Function in Subjects with and without Increased Insulin Resistance
Authors: Gómez-Sánchez Marta , Gómez-Sánchez Leticia , Llamas-Ramos Rocío , Rodríguez-Sánchez Emiliano , García-Ortiz Luis , Martí-Lluch Ruth , Rodríguez María Cortés , Llamas-Ramos Inés , Gómez-Marcos Manuel A.
Published: September 2024

(1) The main aim of this study was to analyze the relationship of the Mediterranean diet (MD) with vascular function in participants with and without increased insulin resistance (IR) in the Spanish population. A secondary aim was to study differences by gender. (2) Methods: Data were analyzed from 3401 subjects in the EVA, MARK, and EVIDENT studies (mean age = 60 years and 57% men). IR was evaluated with the triglyceride and glucose index (TyG index). TyG index = Ln [(fasting triglyceride mg/dL × fasting glucose mg/dL)/2]. The MD was measured against the MEDAS questionnaire, with the 14 items used in the PREDIMED study. Vascular stiffness was estimated with the brachial–ankle pulse wave velocity (baPWV) and the cardio ankle vascular index (CAVI) using the Vasera VS-1500®. (3) Results: The mean MEDAS value was 5.82 ± 2.03; (men: 5.66 ± 2.06; women: 6.04 ± 1.99; p < 0.001). MD adherence was 36.8% (men: 34.2%; women: 40.3%; p < 0.001). The mean baPWV value was 14.39 ± 2.78; (men: 14.50 ± 2.65; women: 14.25 ± 2.93; p = 0.005). A baPWV value ≥ 14.5 m/s was found in 43.4% (men: 43.6%; women: 40.0%; p = 0.727). The mean CAVI value was 8.59 ± 1.28; (men: 8.75 ± 1.28; women: 8.37 ± 1.26; p < 0.001). CAVI values ≥ 9 were present in 39.0% (men: 44.4%; women: 31.7%; p < 0.001). The mean value of the TGC/G index was 10.93 ± 1.39; (men: 11.08 ± 1.33; women: 10.73 ± 1.43; p < 0.001). IR was found in 49.9%. The average value of the MD score value was negatively associated with baPWV and CAVI in all groups analyzed (<0.05), except in the group of women with insulin resistance. (4) Conclusions: The results suggest that MD adherence is negatively associated with the vascular stiffness parameters analyzed in all the groups studied except the group of women with insulin resistance.
Searching for Beauty and Health: Aging in Women, Nutrition, and the Secret in Telomeres
Authors: Boccardi Virginia , Polom Joanna
Published: September 2024

Women typically outlive men, yet they often experience greater frailty and a higher incidence of chronic diseases as they age. By exploring the biological foundations of aging, with a particular focus on telomere dynamics, this manuscript aims to describe how dietary and lifestyle choices can significantly influence the aging process. The review comprehensively examines current research, underscoring the power of nutrition to counteract age-related changes, support healthy aging, and maintain vitality and beauty in women. The exploration of telomeres—the protective caps at the ends of chromosomes—reveals how they serve as markers of cellular aging and are potential targets for interventions aimed at enhancing women’s longevity and quality of life. This study also emphasizes the importance of sex-specific approaches and precision medicine in understanding the unique health challenges women face as they age. By proposing targeted strategies, the review seeks to address these challenges, offering insights into preventive measures that can foster resilience, promote well-being, and extend healthy life expectancy in women. Ultimately, this work provides a sophisticated understanding of the aging process in women, highlighting the pivotal role of tailored interventions in preserving both health and beauty.
Investigating the Impact of Nutrition and Oxidative Stress on Attention Deficit Hyperactivity Disorder
Authors: Visternicu Malina , Rarinca Viorica , Burlui Vasile , Halitchi Gabriela , Ciobică Alin , Singeap Ana-Maria , Dobrin Romeo , Mavroudis Ioannis , Trifan Anca
Published: September 2024

Background/Objectives: Attention deficit hyperactivity disorder (ADHD) is the most common childhood-onset neurodevelopmental disorder, characterized by difficulty maintaining attention, impulsivity, and hyperactivity. While the cause of this disorder is still unclear, recent studies have stated that heredity is important in the development of ADHD. This is linked to a few comorbidities, including depression, criminal behavior, and anxiety. Although genetic factors influence ADHD symptoms, there are also non-genetic factors, one of which is oxidative stress (OS), which plays a role in the pathogenesis and symptoms of ADHD. This review aims to explore the role of OS in ADHD and its connection to antioxidant enzyme levels, as well as the gut–brain axis (GBA), focusing on diet and its influence on ADHD symptoms, particularly in adults with comorbid conditions. Methods: The literature search included the main available databases (e.g., Science Direct, PubMed, and Google Scholar). Articles in the English language were taken into consideration and our screening was conducted based on several words such as “ADHD”, “oxidative stress”, “diet”, “gut–brain axis”, and “gut microbiota.” The review focused on studies examining the link between oxidative stress and ADHD, the role of the gut–brain axis, and the potential impact of dietary interventions. Results: Oxidative stress plays a critical role in the development and manifestation of ADHD symptoms. Studies have shown that individuals with ADHD exhibit reduced levels of key antioxidant enzymes, including glutathione peroxidase (GPx), catalase (CAT), and superoxide dismutase (SOD), as well as a diminished total antioxidant status (TOS) compared to healthy controls. Additionally, there is evidence of a close bidirectional interaction between the nervous system and gut microbiota, mediated by the gut–brain axis. This relationship suggests that dietary interventions targeting gut health may influence ADHD symptoms and related comorbidities. Conclusions: Oxidative stress and the gut–brain axis are key factors in the pathogenesis of ADHD, particularly in adults with comorbid conditions. A better understanding of these mechanisms could lead to more targeted treatments, including dietary interventions, to mitigate ADHD symptoms. Further research is required to explore the therapeutic potential of modulating oxidative stress and gut microbiota in the management of ADHD.
Maternal Folic Acid and Dietary Folate Intake in Relation to Sex Ratio at Birth and Sex-Specific Birth Weight in China
Authors: Zhang Binyan , Mi Baibing , Dang Shaonong , Yan Hong
Published: September 2024

Background: It is well-established that prenatal folic acid supplements can reduce neural tube defects. However, the associations between folic acid supplementation, dietary folate intake, and overall folate intake with sex-specific birth outcomes are not yet fully understood. Objectives: This study aims to investigate the association of periconceptional folic acid supplement, dietary folate, and total folate intake with the sex ratio at birth and sex-specific birth weight. Methods: Data were sourced from a cross-sectional survey conducted between August and December 2013 in Northwest China, involving 7318 infants and their mothers, recruited using a stratified multistage random sampling method. Folic acid supplements (400 μg/d) were ascertained via a retrospective in-person interview. Dietary folate was evaluated using a validated food frequency questionnaire. Birth outcomes, including sex and weight at birth, were obtained from the Medical Certificate of Birth. Generalized linear models were employed to calculate relative risks (RRs) or differences with 95% confidence intervals (CIs). Results: No association or dose–response relationship was observed between folic acid supplement, dietary folate, and total folate intake during periconception and the likelihood of male births. However, women who took folic acid supplements during pre- and post-conception were associated with an increased male birth weight by 52.8 (8.1 to 97.5) g. Additionally, the total folate intake during periconception was associated with birth weight for males (upper vs. lower tertile: β = 38.8, 95%CI: 5.0 to 72.5 g, p-trend = 0.024) and females (upper vs. lower tertile: β = 42.4, 95%CI: 6.7 to 78.1; p-trend = 0.022). Conclusions: Our findings indicate that periconceptional total folate intake does not correlate with sex ratio at birth but was positively linked to infant birth weights, regardless of gender. These findings offer novel insights into potential benefits of total folate intake, beyond the prevention of neural tube defects, for policymakers and public health.
A Short-Term Evaluation of the Eat and Exercise to Win Program for Adults with Intellectual and Developmental Disabilities
Authors: Nabors Laura , Bauer Anne , Ayers Kara , Workman Brandon , Butsch Kovacic Melinda , Lee Seung-Yeon
Published: September 2024

(1) Study Aim: Adults with intellectual and developmental disabilities (IDD) face a multitude of chronic health risks related to obesity, including diabetes and heart disease. Day adult service programs offer unique opportunities for improving and monitoring the health of this vulnerable group. To promote exercise and healthy eating habits among adults with IDD, the Eat and Exercise to Win Program (EE-2-Win) was offered weekly at two locations over 8–9 months. (2) Methods: Using daily logs, staff assessed outcomes of 26 program participants, including changes in knowledge, eating and exercise habits, and water consumption. Participants’ weights were measured, and their lunches were photographed at baseline and 3 months. (3) Results: While participants’ weights did not significantly differ at 3 months, assessing photographs indicated that participants’ lunches included more fruits and vegetables. Staff surveys indicated that participants had greater knowledge of MyPlate and were consuming more water at three months. Survey responses indicated that staff perceived the program to be valuable overall, and challenges in learning and assessment were reported given differences in the cognitive abilities of adults with IDD. Staff also suggested engaging home caregivers in the program, as they often make dietary decisions. (4) Conclusions: Overall, results confirmed that the EE-2-Win Program positively impacted healthy eating and exercise. Future work, however, with both staff and caregivers is needed to further optimize the program.
Polyphenol-Rich Cranberry Beverage Positively Affected Skin Health, Skin Lipids, Skin Microbiome, Inflammation, and Oxidative Stress in Women in a Randomized Controlled Trial
Authors: Christman Lindsey , De Benedetto Anna , Johnson Elizabeth , Khoo Christina , Gu Liwei
Published: September 2024

This study aimed to determine whether a polyphenol-rich cranberry beverage affects skin properties, lipids, and the microbiome in women using a randomized, double-blinded, placebo-controlled, cross-over design. Twenty-two women with Fitzpatrick skin types 2–3 were randomized to drink a cranberry beverage or placebo for six weeks. After a 21-day washout, they consumed the opposite beverage for six weeks. Six weeks of cranberry beverage significantly reduced UVB-induced erythema, improved net elasticity on the face and forearm, smoothness on the face, and gross elasticity on the forearm compared to the placebo. When stratified by age, these effects of the cranberry beverage were primarily observed in women >40 years old. SOD activities were improved after six weeks of cranberry beverage consumption compared to the placebo, while glutathione peroxide and TNF-α were improved compared to baseline. These effects were found to differ by age group. Skin lipid composition was modulated by both the cranberry beverage and the placebo. Cranberry beverages did not change α- or β-diversity but altered the abundance of several skin microbes at the species and strain level. Consumption of a cranberry beverage for six weeks improved specific skin properties and oxidative stress and modulated skin lipids and microbiome compared to placebo.