bluuebunny/crossref_metadata_2025 huggingface dataset:
Preparation and Characterization of Graphene and Carbon Nanotube Hybrid Polydimethylsiloxane Composites for Protective Coating Applications
Authors: Ketikis Panayiotis , Tsalas Ioannis , Klonos Panagiotis A. , Pilatos George , Giannakopoulou Tatiana , Kyritsis Apostolos , Trapalis Christos , Tarantili Petroula A.
Published: December 2024

In this work, the synergistic effect of graphene nanosheets (GNs), as well as multiwalled carbon nanotubes (MWCNTs), as reinforcing agents of polydimethylsiloxane (PDMS) was investigated, in order to explore the possibilities of designing composite materials, tailored for use in the field of coatings, which might be, in fact, a very interesting application. It was shown that the addition of GNs and MWCNTs in PDMS matrices significantly improves the thermal stability of the obtained nanocomposites, especially those reinforced exclusively with GNs. The tensile tests indicated that strength increased for all the examined composites. It was also observed that the Young’s moduli had an increasing trend, with the exception of the composites containing only GNs, while those reinforced solely with MWCNTs exhibited the best performance. The O2 permeability measurements revealed that the highest reduction in the permeability was observed in GN-MWCNT/PDMS composite membranes, in comparison to those reinforced only with graphene or carbon nanotubes. Dielectric relaxation spectroscopy showed that all the examined composites, and especially those of MWCNTs, possess electrical conductivity, apart from the samples reinforced exclusively with graphene. The electromagnetic shielding effectiveness was also improved at higher filler loadings, which is more evident in composites reinforced with MWCNTs. It was concluded that the improved properties of the above studied hybrid composites make them suitable for protective coating applications.
Experimental Study of Submarine Pipeline with Geotextile and Stone Cover Protection Under the Superposition of Waves and Currents
Authors: Si Wenqi , Wang Mingqing , Gao Yaru , Sun Ke , Chen Bing , Wang Risheng , Cui Lin , Jeng Dong-Sheng , Zhao Hongyi
Published: December 2024

Submarine pipelines are the main transport carriers of marine resources. In order to protect these pipelines, geotextile and stone covering measures are adopted in this paper and the protective effect is studied. A sequence of physical model tests was conducted to carry out the research. The hydrodynamic characteristics and seabed oscillation response of the seabed surrounding the pipeline were analyzed with or without geotextile and stone cover protection, and it was found that they were affected by waves (and currents). The experimental results show the following: (1) comparing the regular wave and current with the regular wave alone, it is found that forward current promotes wave propagation and reverse current inhibits wave propagation; (2) the protective effect of geotextile and stone covering measures on different positions of the pipeline (the front, the bottom, and the back of the pipe) is basically same; (3) in the case of waves with large wave heights and long wave periods superimposed with ocean currents, the protective effect of geotextile and stone coverings on the hydrodynamic and seabed pore pressure around the pipeline is more significant.
Matching Trees to Streets by Street Type: A Case Study of Street Tree Suitability and Services in a Highly Urbanized City
Authors: Nam Heejung , Hong Seunghyun , Im Dohyuk , Maeng Ayun , Je Sunmi , Kang Wanmo , Chang Hanna
Published: December 2024

Street trees are a representative form of urban green space that play an important role in mitigating the environmental impact of urbanization. Planting the right tree in the right place in urban streetscapes can improve tree health and ecosystem services. Here, we propose a novel approach to selecting appropriate street trees using street type classifications. In the highly urbanized area of Uijeongbu City, South Korea, 221.9 km of streets with 19,717 street trees were classified into 12 types based on road width, aspect ratio, land use, and the presence of power lines. Appropriate tree species were selected for each street type, taking into account tree traits and functions as well as street environments. Then, we analyzed the structure and ecosystem-regulating services of street trees by type, also comparing the services of appropriate and non-appropriate trees. As a result, all 12 street types were identified, but their distribution was uneven. Tree dimension was the key factor in determining appropriate species, and, for the second most common street type, characterized by narrow roads, low aspect ratios, and power lines, only four appropriate species were identified, indicating an urgent need for more options. Additionally, the most dominant species accounted for over 20%, averaging 44% across the 12 street types, further highlighting the necessity of introducing more diverse tree species. Overall, appropriate street trees generally provided higher service efficiency compared to non-appropriate trees across four ecosystem regulating services. These findings emphasize the need for policies and guidelines that promote street tree diversity and enhance the ecological benefits of street trees. This study provides a foundation for developing sustainable street tree management strategies that contribute to healthier and more resilient urban streetscapes.
Assessing and Optimizing the Connectivity of the Outdoor Green Recreation Network in Zhengzhou from the Perspective of Green Travel
Authors: Yan Jingjing , Fan Siyu , Tian Guohang , Mu Tao , Liu He , Zhang Yali , Mu Bo
Published: December 2024

With the increasing demand for outdoor recreation and fitness, this study aims to assess the connectivity of the outdoor green recreation (OGR) network from the perspective of green travel and propose optimization framework. The Point of Interest (POI) and Area of Interest (AOI) datasets of OGR spots in Zhengzhou were utilized as the primary research materials. A combination of GIS spatial analysis and Graph index calculation is employed to quantify and diagnose the connectivity of the OGR network based on multi-source data (land cover, topography, and road network). The index system for cost surface establishment was improved and proposed, shifting its focus from previous biological migration and ecological network to human green travel and improving the connectivity of the OGR network. The technical optimization process of the OGR network is explored and presented. The results show that: (1) The scale, number, and distribution of OGR spots and the connectivity of the OGR network are significantly different in urban and rural areas. Numerous small-scale OGR spots and short-distance recreational paths are distributed in urban areas, while a limited number of large-scale OGR spots and long-distance recreational paths are situated in rural areas with better natural resources. (2) Compared with driving travel, the connectivity of the OGR network is poor when walking and cycling. Graph indexes of Dg, BC, and dPC can be used to reflect the connection capability, bridging role, and contribution of each spot to overall network connectivity. (3) The current OGR network is optimized through 30 new spots based on the perspective of green travel and land suitability analysis. The network connectivity will improve by 4%, and the number of recreational paths suitable for green travel increased by 41. (4) The methodologies for quantifying and optimizing OGR network connectivity from the perspective of green travel will offer valuable references for future research in this field.
Arthrocentesis of Temporomandibular Joints—A Clinical Comparative Study
Authors: Siewert Marta , Pokrowiecki Rafał , Zawadzki Paweł J. , Stopa Zygmunt
Published: December 2024

The objective of this study was to compare single-needle arthrocentesis with the conventional two-needle arthrocentesis, as well as the additional intracapsular injection of hyaluronic acid or platelet-rich fibrin. A total of 96 patients with established osteoarthritis (OA) (n = 48) or with internal de-arrangement (DD) (n = 48) were assigned single-needle arthrocentesis with distension of the joint or conventional two-needle arthrocentesis with or without intracapsular injection of the medication (hyaluronic acid (HA) or platelet-rich plasma (PRP)) performed every month over a period of 6 months. The maximum mouth opening and pain, as measured by the visual analog scale (VAS), were compared. Each group exhibited significant improvement, i.e., a decrease in pain and an increase in mouth opening. The single-puncture technique provided similar pain reduction as the two-needle approach but provided significantly better results in terms of maximum mouth opening. The reduction in pain was similar when comparing the OA and DD cohorts; however, patients with disc displacement achieved significantly better mouth opening than OA. Intracapsular application of medication contributed to a significant decrease in pain in both HA and PRP groups, with platelet-rich fibrin being significantly superior to HA in terms of mouth opening improvement.
Impact of Influence of Piston Design Parameters on the Hydrodynamic Characteristics of Internal Combustion Engines—A Numerical Study
Authors: Menacer Brahim , Narayan Sunny , Tuninetti Víctor , Khatir Tawfiq , Oñate Angelo , Osorio Liomnis , Abubakar Shitu , Samuel Joseph , Grujic Ivan , Stojanovic Nadica , Kaisan Muhammad Usman
Published: December 2024

Piston top rings in the combustion engine play a crucial role in the overall hydrodynamic performance of engines, such as power loss, minimum film thickness and friction forces, by ensuring sealing and minimizing the leakage of burnt gases. This present paper examines the influence of four key parameters of the top ring, such as ring width, ring temperature, ring tension, and ring surface roughness on the hydrodynamic behavior at the ring/cylinder contact. These parameters play a significant role in the formation and maintenance of the oil film, directly influencing hydrodynamic indicators such as the minimum oil film thickness, friction force, power loss, oil pressure, and the ring angle twist. This article relies on hydrodynamic models and numerical simulations performed using GT-SUITE version 6 software to analyze these effects. The pressure curve used in this simulation is experimentally validated for an engine speed of 2000 RPM. It was found that an increase in the top ring temperature reduces the oil’s viscosity, decreasing the film thickness and increasing the risk of metal-to-metal contact. Increasing the roughness of the ring enhances oil film stability, especially at the bottom dead center (BDC) points during each phase of the operating cycle. Further, three different types of ring profiles were investigated for friction forces by varying the speed of the engine.
Environmental and Economic LCA Comparison of Flexural Strengthening Solutions for a Reinforced Concrete Beam
Authors: Pedroso Pedro Frazão , Correia João R. , Silvestre José D. , Firmo João P. , Garrido Mário
Published: December 2024

The construction sector is one of the largest creators and distributors of wealth, contributing to economic growth worldwide. However, this economic growth comes together with very high environmental impacts. Thus, rehabilitation solutions that can adapt the current building stock to today’s structural requirements are needed, increasing structural safety, while avoiding the production of demolition waste and the extraction of virgin raw materials, hence lowering the construction sector’s environmental impacts. Such rehabilitation solutions need to be environmentally and economically sound so that stakeholders can make informed decisions based on their needs and priorities. This paper presents a case study of an existing reinforced concrete beam, whose flexural resistance is increased using four alternative strengthening solutions: concrete jacketing, without and with increasing the cross-section size, and plate bonding, using either carbon fibre-reinforced polymer (CFRP) strips or steel plates. These solutions are studied via an environmental and economic cradle-to-gate life cycle assessment (LCA), resulting in a comprehensive comparison of their environmental and economic impacts, followed by a multicriteria and sensitivity analysis and eco-cost approach to determine the optimal solution. According to the criteria considered in the study, when environmental impacts are more valued, the concrete jacketing solution presents the best results and, when cost is dominant in the decision, the bonding of CFRP strips becomes the optimal solution.
Detection of Hydrogen Peroxide Vapors Using Acidified Titanium(IV)-Based Test Strips
Authors: Hossain Rayhan , Materer Nicholas F.
Published: December 2024

One method for the colorimetric detection of hydrogen peroxide vapor is based on a titanium–hydrogen peroxide complex. A color changing material based on a titania hydroxypropyl cellulose thin film was initially developed. However, as this material dries, the sensitivity of the material is significantly reduced. Thus, an alternative sensing material, based on titanium(IV) oxysulfate, an ionic liquid, and in some cases, triflouromethanesulfonic acid adsorbed onto low-cost silicon thin-layer chromatography (TLC) plates, was developed. TiO2 was heated with concentrated sulfuric acid in a controlled environment, usually at temperatures ranging from 100 °C to 250 °C. These sensors are disposable and single-use and are simple and inexpensive. When the resulting thin-film sensors are exposed to ppm levels of hydrogen peroxide vapor, they turn from a white reflective material to an intense yellow or orange. Ti(IV) oxysulfate combined with an acid catalyst and an ionic-liquid-based material provides an opportunity to enhance the sensor activity towards the peroxide vapor and decreases the detection limit. Kinetic measurements were made by the quantification of the intensity of the reflected light as a function of the exposure time from the sensor in a special cell using a low-cost web camera and a tungsten lamp. The measured rate of the color change indicates high sensitivity and first-order kinetics over a hydrogen peroxide concentration range of approximately 2 to 31 ppm. These new materials are a starting point for the preparation of more active sensor materials for hydrogen peroxide and organic peroxide vapor detection.
CMAS Corrosion Behavior of Mid-Entropy Rare-Earth Hafnate (Y0.3Gd0.3Yb0.4)4Hf3O12 as Thermal Barrier Coating Candidate
Authors: Ye Fuxing , Yao Yuan , Meng Fanwei , Luo Tianyuan
Published: December 2024

High-temperature CMAS corrosion has become a crucial factor inhibiting the further development of thermal barrier coatings (TBCs) because of the increasing service temperature of aero-engines. Herein, a novel mid-entropy rare-earth hafnate (Y0.3Gd0.3Yb0.4)4Hf3O12 (YGYbH) was prepared by ultrafast high-temperature sintering (UHS) technology, and its CMAS corrosion behavior and mechanism were investigated. During corrosion, the Ca2RE8(SiO4)6O2 apatite phase with a lower formation enthalpy and entropy-stabilized effect had a more intense tendency to be generated, which improves the density and stability of the reaction layer, hindering the further penetration of molten CMAS. Moreover, the significant lattice distortion caused by the rare-earth ions with different radii impeded the ionic diffusion, which delayed the CMAS corrosion reaction. In general, YGYbH, with excellent CMAS corrosion resistance, has the potential to serve as a next-generation TBC material.
Mechanical Properties and Damage Constitutive Model of Saturated Sandstone Under Freeze–Thaw Action
Authors: Feng Meimei , Cao Xiaoxiao , Wu Taifeng , Yuan Kangsheng
Published: December 2024

In order to investigate the impact of freeze–thaw damage on sandstone under the coupling of ground stress and pore water pressure, three types of porous sandstone were subjected to freezing at different negative temperatures (−5 °C, −10 °C, −15 °C, and −20 °C). Subsequently, hydraulic coupling triaxial compression tests were conducted on the frozen and thawed sandstone. We analyzed the effects of porosity and freezing temperature on the mechanical properties of sandstone under hydraulic coupling and performed nuclear magnetic resonance tests on sandstone samples before and after freezing and thawing. The evolution of the pore structure in sandstone at various freezing and thawing stages was studied, and a statistical damage constitutive model was established to validate the test results. The results indicate that the stress–strain curves of sandstone samples under triaxial compression after a freeze–thaw cycle exhibit minimal changes compared to those without freezing at normal temperature. The peak deviator stress shows a decreasing trend with decreasing freezing temperature, particularly between −5 °C and −10 °C, and then gradually stabilizes. The elastic modulus of sandstone with different porosity decreases with the decrease in freezing temperature, and the decrease is more obvious in the range of −5 °C~−10 °C, decreasing by 2.33%, 6.11%, and 10.5%, respectively. Below −10 °C, the elastic modulus becomes similar to that at −10 °C, and the change tends to stabilize. The nuclear magnetic porosity of sandstone samples significantly increases after freezing and thawing. The smaller the initial porosity, the greater the rate of change in nuclear magnetic porosity after a freeze–thaw cycle. The effects of freeze–thaw damage on the T2 distribution of sandstone with different porosity levels vary. We established a statistical damage constitutive model considering the combined effects of freeze–thaw damage, ground stress, and pore water pressure. The compaction coefficient K was introduced into the constitutive model for optimization. The change trend of the theoretical curve closely aligns with that of the test curve, better characterizing the stress–strain relationship of sandstone under complex pressure environments. The research findings can provide a scientific basis for wellbore wall design and subsequent maintenance in complex environments.
Numerical Analysis and Theoretical Study on the Interfacial Bonding Behavior of High-Strength Steel Stainless Wire Mesh-Reinforced ECC and Concrete
Authors: Li Chao , Zou Yao , Li Ziyuan , Zou Xuyan , Li Ke , Zhu Juntao , Xiao Hongbo , Fan Jianwei
Published: December 2024

In order to investigate the interfacial bonding properties of high-strength steel stainless wire mesh-reinforced ECC (HSSWM-ECC) and concrete, a finite element model was established for two types of interfaces based on experimental research. The results show that the failure modes observed in the 21 groups of simulations can be classified into three categories: debonding failure, ECC extrusion failure and concrete splitting failure. The failure mode was mainly affected by the type of interface. The effective anchorage length is inversely proportional to the strength of the concrete and proportional to the stiffness and thickness of the HSSWM-ECC. The capacity of the roughening interface is positively correlated with the concrete strength and bonding length, but negatively correlated with the interfacial width ratio. Increasing both the number and width of grooves within the effective range enhances the interfacial capacity, whereas higher concrete strengths tend to reduce it. Based on the above results, calculation models for the effective anchorage length and bearing capacity were established separately for the two types of interfaces. The theoretical model for the interfacial bonding property between HSSWM-ECC and concrete has been refined. These advancements establish a theoretical groundwork for the design of concrete structures strengthened with HSSWM-ECC.
Progress in Additive Manufacturing of High-Entropy Alloys
Authors: Chen Bin
Published: December 2024

High-entropy alloys (HEAs) have drawn substantial attention on account of their outstanding properties. Additive manufacturing (AM), which has emerged as a successful approach for fabricating metallic materials, allows for the production of complex components based on three-dimensional (3D) computer-aided design (CAD) models. This paper reviews the advancements in the AM of HEAs, encompassing a variety of AM techniques, including selective laser melting (SLM), selective laser sintering (SLS), selective electron beam melting (SEBM), directed energy deposition (DED), binder jetting (BJT), direct ink writing (DIW), and additive friction stir deposition (AFSD). Additionally, the study discusses the powders and wires utilized in AM, the post-processing of AM-processed HEAs, as well as the mechanical and corrosion properties of these alloys. The unique ultra-fine and non-equilibrium microstructures achieved through AM result in superior mechanical properties of HEAs, like improved strength and ductility. However, research regarding certain aspects of HEA AM, such as fatigue properties and creep deformation behavior, is still relatively scarce. Future research should focus on overcoming the existing limitations and exploring the potential of HEAs in various applications.
Behavior of Weathering Steel in Artificial Harsh Environment
Authors: Wierzbicki Tomasz , Rutkowska Gabriela , Żółtowski Mariusz , Nagirniak Mykola
Published: December 2024

The safety and durability of engineering structures, like bridges, which are designed from weathering steels, are conditioned by the development of a sufficiently protective layer of corrosion products. Air pollution, the microclimate around the bridge, the time of wetness, the structural solution of the bridge, and the position and orientation of the surface within the bridge structure all influence the development of protective layers on the surface of the weathering steel. The condition of the formed patina relies on the working conditions of the structure. In fact, it is exposed to various types of salts that appear during the operation of the facility. In this article, the strength parameters of uncoated weathering steel were tested after accelerated aging of welded steel samples in a salt spray chamber. The tests showed the expected degradation of steel after long-term exposure to salt and changes in the strength parameters such as tensile strength, yield strength, and, importantly, impact strength, both in the steel itself and in the elements of the welded connection. The obtained results showed that the change is influenced by both the conditions in which the samples are made (welding method) and the direction of the welded joint (along or across the rolling direction).
Surface-Grinding-Induced Recrystallization and Metal Flow Causes Corrosion-Assisted Penetrating Attack of High-Mn–Low-CR Casting Steel in Humid Environments
Authors: Park Jin Sung , Kang Myeong Hun , Kim Sung Jin
Published: December 2024

This study examined the surface-grinding-induced microstructural modifications and corrosion attacks in a penetrating form of a high-Mn–low-Cr casting steel slab under humid environments. Various experimental and analytical findings from field-emission scanning electron microscopy, electron backscatter diffraction, transmission electron microscopy, and electrochemical analyses revealed that the abrasive grinding process led to the formation of a surface deformed region, comprising a recrystallized fine grain layer and multiple streamlines. Corrosion initially occurs preferentially along the boundary areas where Cr(Mn)23C6 particles are precipitated. Moreover, the corrosion products (Fe-based oxy/hydroxides) with a high volumetric expansion ratio detach readily from the surface deformed regions, facilitating the easy penetration of corrosive media. In contrast to conventional low-alloyed steels, which exhibit uniform corrosion behavior, corrosion-assisted penetrating attacks on ground high-Mn–low-Cr casting steel slabs occur more severely and frequently during the summer/dry season (i.e., relative humidity levels around 60% to 80%, rather than 100%) when a thin water film can form on the steel surface. Based on the result, effective technical strategies in terms of metallurgical and environmental aspects to mitigate the risk of corrosion-assisted penetrating attack of high-Mn–low-Cr casting steel were discussed.
Effect of Al7Cu2Fe Particles on the Anisotropic Mechanical Properties and Formability of Al-Zn-Mg-Cu-Based Alloy Sheets
Authors: Jeon Jonggyu , Lee Sangjun , Jeon Jeheon , Kang Maru , Kang Heon
Published: December 2024

The presence of Al7Cu2Fe particles, formed due to Fe impurities in Al-Zn-Mg-Cu alloys, significantly impacts mechanical properties and formability, which is crucial for the use of these alloys in the automotive and aerospace industries. In this study, we prepared Al-Zn-Mg-Cu-based alloy sheets with large (LF), small (SF), and no (NF) Al7Cu2Fe particles to explore their effects on recrystallization and mechanical behavior. These sheets were fabricated using controlled cooling rates and subsequent thermo-mechanical processing. Fine dispersion of Al7Cu2Fe particles in the SF sheet led to a substantial reduction in grain size (16.5 μm) and an increase in yield strength (168.6 MPa), albeit with lower ductility (24.6%). In contrast, the NF sheet exhibited a lower yield strength (141.5 MPa) but superior ductility (35.8%) due to the absence of Al7Cu2Fe particles, which prevented premature fracture. The SF sheet demonstrated lower anisotropy in ductility due to the uniform recrystallized grain orientations, while the LF and NF sheets exhibited significant anisotropy in yield strength. These findings indicate that optimizing Al7Cu2Fe particle dispersion is key to balancing the strength, ductility, and anisotropy in Al-Zn-Mg-Cu alloys.
Variable Dose-Constraints Method for Enhancing Intensity-Modulated Radiation Therapy Treatment Planning
Authors: Obata Norihisa , Abou Al-Ola Omar M. , Nakada Ryosei , Kojima Takeshi , Yoshinaga Tetsuya
Published: December 2024

The conventional approach to intensity-modulated radiation therapy treatment planning involves two distinct strategies: optimizing an evaluation function while accounting for dose constraints, and solving feasibility problems using feasibility-seeking projection methods that incorporate inequality constraints. This paper introduces a novel iterative scheme within the framework of continuous dynamical systems, wherein constraint conditions dynamically evolve to enhance the optimization process. The validity of dynamically varying dose constraints is theoretically established through the foundation of continuous-time dynamical systems theory. In particular, we formalize a system of differential equations, with both beam coefficients and dose constraints modeled as state variables. The asymptotic stability of the system’s equilibrium is rigorously proven, ensuring convergence to a solution. In practical terms, we leverage a discretized iteration formula derived from the continuous-time system to achieve rapid computational speed. The mathematical structure of the proposed approach, which directly incorporates dose-volume constraints into the objective function, facilitates significant computational efficiency and solution refinement. The proposed method has an inherent dynamics that approaches more desirable solutions within the set of solutions when the solution to the optimization problem is not an isolated point. This property guarantees the identification of optimal solutions that respect the prescribed dose-volume constraints while enhancing accuracy when such constraints are feasible. By treating dose constraints as variables and concurrently solving the optimization problem with beam coefficients, we can achieve more accurate results when compared with using fixed values for prescribed dose conditions.
The Effect of Phosphorus Concentration on the Co-Production of Fucoxanthin and Fatty Acids in Conticribra weissflogii
Authors: Zhang Ning , Peng Di , Rui Xiangyu , Zheng Wenquan , Zeng Zhenglin , Huang Xianghu , Li Changling , Li Feng
Published: December 2024

The production of fucoxanthin and fatty acids in Conticribra weissflogii has been examined, but the role of elements like phosphorus in their mutualistic interactions is not well understood. To fill this gap, our study utilized potassium dihydrogen phosphate (KH2PO4) as a source of phosphorus to examine its impact on the synthesis of fucoxanthin and fatty acids in C. weissflogii. Our findings revealed that at a phosphorus concentration of 10 mg L−1, the cell density (9.5 × 105 cells mL−1), carotenoid concentration (1.67 mg g−1), fucoxanthin concentration (0.91 mg L−1), and fucoxanthin content (1.33 mg g−1) were maximized. Additionally, at a phosphorus concentration of 20 mg L−1, cell dry weight (0.76 ± 0.08 g L−1), total fatty acid content, saturated fatty acids, and unsaturated fatty acids were all at their highest levels, making this concentration optimal for EPA accumulation. In conclusion, manipulating the phosphorus concentration can enhance the levels of fucoxanthin and unsaturated fatty acids in C. weissflogii, offering valuable insights into the co-production of these two high-value compounds within this species.
Optimized Extraction of Sargahydroquinoic Acid, Major Bioactive Substance, from Sargassum yezoense Using Response Surface Methodology
Authors: Baek Suhyeon , Bae Ji-Eun , Miao Yu , Kim Gahyeon , Ryu Bomi , Lee Byung-Hoo , Lee Sanggil
Published: December 2024

Sargahydroquinoic acid (SHQA), a bioactive compound found in certain Sargassum species, exhibits significant health benefits. This study optimized the extraction of SHQA from Sargassum yezoense using response surface methodology (RSM) and evaluated its antioxidant effects through in vitro and in vivo assays. A Box–Behnken design (BBD) was effectively employed to investigate the effects of incubation temperature, time, and ethanol concentration on SHQA yield, achieving a high coefficient of determination (R2 = 0.961). Analysis of variance (ANOVA) validated the model’s reliability (F = 13.86, p = 0.005) and highlighted ethanol concentration as a highly significant factor (p < 0.001). Optimal extraction conditions were identified as 52.8 °C, 8.3 h, and 74.1% ethanol. The SHQA-maximized extract (SME) contained 67.8 ± 0.6 mg SHQA/g and 25.00 ± 1.01 mg phloroglucinol equivalent/g. SME exhibited antioxidant capacity of 26.45 ± 0.66 mg and 28.74 ± 2.30 mg vitamin C equivalent/g in ABTS and DPPH assays, respectively, and 0.29 ± 0.02 mM FeSO4 equivalent/g in the FRAP assay. Additionally, SME at 50 µg/mL and SHQA at 1 µg/mL inhibited reactive oxygen species (ROS) generation in an H2O2-induced zebrafish model. This study presents the first optimization of SHQA extraction using RSM and demonstrates SHQA’s ROS inhibition in a zebrafish model.
A Comparative Analysis of Toxicology and Non-Toxicology Care in Intoxicated Patients with Acute Kidney Injury
Authors: Pan Chi-Syuan , Chen Chun-Hung , Chen Wei-Kung , Mu Han-Wei , Yang Kai-Wei , Yu Jiun-Hao
Published: December 2024

Background and Objectives: Intoxicated patients with acute kidney injury (AKI) experience high morbidity and mortality. While prior studies suggest that toxicology care settings improve outcomes, the impact of care settings on patients with AKI remains unclear. This study aimed to compare the outcomes of intoxicated patients with AKI managed in toxicology versus non-toxicology care settings. Materials and Methods: This retrospective cohort study included intoxicated patients admitted to a tertiary hospital between January 2022 and December 2023. Patients were categorized into toxicology and non-toxicology care settings. Demographic characteristics, clinical outcomes focusing on mortality and length of hospital stay, and evaluation scores were compared. Results: A total of 31 intoxicated patients with AKI were included in the study. There were no significant differences in mortality or hospital length of stay between toxicology and non-toxicology care settings. However, the mortality rate in the AKI group was significantly higher (16%) compared to intoxicated patients without AKI (1.9%). Additionally, hospital stays were consistently longer in the AKI group than in the non-AKI group across all age groups. Conclusions: Hospital length of stay and mortality did not differ significantly between toxicology and non-toxicology care settings for intoxicated patients with AKI. However, both hospital length of stay and mortality were notably higher in patients with AKI compared to those without AKI.
Evaluation of Coronary Artery Calcium Score (CACS) in Dipper and Non-Dipper Hypertensive Patients with Moderate and High Cardiovascular Disease Risks
Authors: Cinar Ahmet , Gedikli Omer , Uyanik Muhammet , Terzi Ozlem
Published: December 2024

Background and Objectives: Hypertension is typically classified into two main groups, “dipper” and “non-dipper”, based on nocturnal blood pressure decline. The coronary artery calcium score (CACS) is an essential biomarker used to assess the presence and severity of coronary artery disease (CAD). This study aims to demonstrate the relationship between CACS and hypertensive patients with moderate-to-high cardiovascular disease (CVD) risk classified as either dipper or non-dipper. Participants and Methods: A total of 167 patients with moderate-to-high CVD risk were divided into two subgroups: 95 patients with dipper hypertension (HT) and 72 with non-dipper hypertension. CACS was measured using coronary computed tomography angiography. Results: In the dipper HT group, there were 60 females (63.2%) and 35 males (36.8%), whereas the non-dipper HT group included 28 females (38.9%) and 44 males (61.1%) (p = 0.002). The mean age was 57 in the dipper HT group and 62 in the non-dipper HT group (p = 0.011). The mean CACS was 93 in the non-dipper HT group and 10 in the dipper HT group (p < 0.001). A history of coronary artery disease was more common in the non-dipper HT group (p = 0.003). Smoking prevalence was higher in the non-dipper HT group (31 patients, 43.1%) compared to the dipper HT group (25 patients, 26.3%) (p = 0.023). Correlation analysis showed that CACS was positively correlated with age, BMI, and HbA1c and negatively correlated with eGFR. Higher CACS values were also observed in males and patients with a history of coronary artery disease, diabetes mellitus, and hyperlipidemia. In univariate analysis, age, male sex, smoking, CAD, CACS, and elevated creatinine were identified as significant risk factors for non-dipper HT (p < 0.05). However, in multivariate analysis, only CACS emerged as a significant independent risk factor (p = 0.001), while other variables were not significant (p > 0.05). The area under the curve (AUC) for CACS was 0.759, indicating statistically significant and excellent discriminative capability (p < 0.001, 95% CI: 0.680–0.839). Conclusions: It was concluded that non-dipper hypertension is associated with higher CACS and indicates a higher cardiovascular risk for this group.
On a Specific Method for Characterizing Ion Exchange Membranes to Assess Their Functionality in Salinity Gradient Power Generation Through Reverse Electrodialysis, Including the Effect of Temperature
Authors: Brauns Etienne , Helsen Joost
Published: December 2024

Salinity gradient power (SGP) by reverse electrodialysis is a promising method for converting SGP into electricity. Instead of the conventional approach of using seawater and freshwater, an alternative method involves using highly concentrated salt solutions (brines) alongside seawater or brackish water. Key factors influencing SGP via reverse electrodialysis (SGP-RE) include the properties of ion exchange membranes, particularly their thickness. This paper outlines a practical experimental set-up that uses both a cation membrane (CM) and an anion membrane (AM). The system is configured with three compartments: two outer compartments filled with highly concentrated brine (HIGH) and a central compartment containing a lower concentration salt solution (LOW), akin to seawater. The compartments are separated by a CM on one side and an AM on the other. The ion transport rate from the HIGH compartments to the central LOW compartment allows for determining the overall ion transport coefficient for thin membranes. Measurements of ion flux and electrochemical voltage under dynamic equilibrium conditions also enable the estimation of the SGP-RE power density (W/m2). By controlling the temperature of the HIGH and LOW solutions, this experiment further investigates the significant impact of temperature on ion transport characteristics.
Effect of Monosaccharides Including Rare Sugars on the Bilayer Phase Behavior of Dimyristoylphosphatidylcholine
Authors: Tamai Nobutake , Kamiya Mei , Kiriyama Nono , Goto Masaki , Fukada Kazuhiro , Matsuki Hitoshi
Published: December 2024

We observed bilayer phase transitions of dimyristoylphosphatidylcholine (DMPC) in aqueous solutions of four kinds of monosaccharides, namely, D-glucose, D-fructose, D-allose and D-psicose, using differential scanning calorimetry (DSC). D-allose (C3-epimer of D-glucose) and D-psicose (C3-epimer of D-fructose) are rare sugars. We performed DSC measurements using two types of sugar-containing sample dispersions of the DMPC vesicles: one is a normal sample dispersion with no concentration asymmetry between the inside and outside of the vesicles and the other is an unusual sample dispersion with a concentration asymmetry. DSC measurements using normal sample dispersions with different sugar concentrations revealed that the temperatures and transition enthalpies of the pre- and main transition of the DMPC bilayer membrane did not significantly depend on the sugar concentration for all monosaccharides. DSC measurements using the unusual sample dispersions demonstrated that the concentration asymmetry caused the splitting of the endothermic peak of the main transition similarly irrespective of the sort of monosaccharides present. From all these DSC results, we conclude that (i) most monosaccharide molecules exist in the bulk water phase, (ii) no specific interaction depending on the molecular structure of each monosaccharide directly occurs between the DMPC and each monosaccharide molecule, and (iii) almost all the effects of the monosaccharides observed in this study are understandable as the general colligative properties of solutions.
Evaluation of the Mechanical and Electrical Properties of Multistage Drawn Copper-Clad Aluminum Wire After Annealing Process
Authors: Song Jung-Woo , Hong Jun-Pyo , An Yeong-Jun , Son Se-Han , Park Jung-Sub , Kim Sung-Heon , Kang Seong-Hoon , Kang Jong-Hun
Published: December 2024

This study evaluates the mechanical and electrical properties of copper-clad aluminum (CCA) wire prepared with a total cross-section reduction of 89% through a multistage cold drawing process and subjected to annealing at various temperatures. In addition to the CCA wire, individual samples of oxygen-free copper and aluminum, drawn with a cross-sectional reduction of 50%, were annealed under the same temperature conditions to enable a comparative analysis. Tensile tests for strength and elongation measurements were conducted, while electrical conductivity was assessed through resistivity tests. SEM and EDS analyses were performed to examine the diffusion thickness and the composition of intermetallic compounds generated at the Al/Cu interface of CCA wire. The tensile strength of the CCA wire decreased and its elongation increased up to 250 °C, after which were maintained. As the annealing temperature increased, intermetallic compound layers of Al2Cu, AlCu, and Al4Cu9 were formed at the Al/Cu interface of the CCA wire, and their thickness increased. Electrical conductivity reaches a maximum at 200 °C and then continuously decreases, showing a negative linear correlation with an increase in the diffusion layer thickness of intermetallic compounds. The study confirmed that cold-drawn CCA wire achieves stable mechanical properties and maximum electrical conductivity at the optimal annealing temperature.
Exploration of Freshness Identification Method for Refrigerated Vegetables Based on Metabolomics
Authors: Meng Zixuan , Zhang Haichao , Wang Jing , Ai Lianfeng , Kang Weijun
Published: December 2024

Background: The rapid development of refrigerated transportation technology for fresh vegetables has extended their shelf life. Some vegetables may appear undamaged on the surface, but their freshness may have decreased, often resulting in the phenomenon of passing off inferior vegetables as good. It is very important to establish a detection method for identifying and assessing the freshness of vegetables. Methods: Therefore, based on metabolomics methods, this study innovatively employed UHPLC-Q-Exactive Orbitrap MS and GC–MS techniques to investigate the metabolites in the refrigerated storage of four vegetables, namely chard (Beta vulgaris var. cicla L), lettuce (Lactuca sativa var. ramose Hort.), crown daisy (Glebionis coronaria (L.) Cass. ex Spach), and tomato (Solanum lycopersicum L.), exploring key biomarkers for assessing their freshness. UPLC-TQ MS was used for the quantitative analysis of key metabolites. Results: The results showed that arginine biosynthesis and the metabolism of alanine, aspartate, and glutamate are key pathways in vegetable metabolism. Four key metabolites were selected from chard, five from lettuce, three from crown daisy, and five from tomato. Conclusions: Comparing the content of substances such as alanine and arginine can help infer the freshness and nutritional value of the vegetables, providing important references for detecting spoilage, determining storage time, and improving transportation conditions. This research holds significant relevance for the vegetable transportation industry.
Neural Networks for Conversion of Simulated NMR Spectra from Low-Field to High-Field for Quantitative Metabolomics
Authors: Johnson Hayden , Tipirneni-Sajja Aaryani
Published: December 2024

Background: The introduction of benchtop NMR instruments has made NMR spectroscopy a more accessible, affordable option for research and industry, but the lower spectral resolution and SNR of a signal acquired on low magnetic field spectrometers may complicate the quantitative analysis of spectra. Methods: In this work, we compare the performance of multiple neural network architectures in the task of converting simulated 100 MHz NMR spectra to 400 MHz with the goal of improving the quality of the low-field spectra for analyte quantification. Multi-layered perceptron networks are also used to directly quantify metabolites in simulated 100 and 400 MHz spectra for comparison. Results: The transformer network was the only architecture in this study capable of reliably converting the low-field NMR spectra to high-field spectra in mixtures of 21 and 87 metabolites. Multi-layered perceptron-based metabolite quantification was slightly more accurate when directly processing the low-field spectra compared to high-field converted spectra, which, at least for the current study, precludes the need for low-to-high-field spectral conversion; however, this comparison of low and high-field quantification necessitates further research, comparison, and experimental validation. Conclusions: The transformer method of NMR data processing was effective in converting low-field simulated spectra to high-field for metabolomic applications and could be further explored to automate processing in other areas of NMR spectroscopy.
Transcriptomic Profiling Reveals Altered Expression of Genes Involved in Metabolic and Immune Processes in NDV-Infected Chicken Embryos
Authors: Muthusamy Malarmathi , Ramasamy Kannaki T. , Peters Sunday Olusola , Palani Srinivasan , Gowthaman Vasudevan , Nagarajan Murali , Karuppusamy Sivakumar , Thangavelu Vasanthakumar , Aranganoor Kannan Thiruvenkadan
Published: December 2024

Objective: The poultry industry is significantly impacted by viral infections, particularly Newcastle Disease Virus (NDV), which leads to substantial economic losses. It is essential to comprehend how the sequence of development affects biological pathways and how early exposure to infections might affect immune responses. Methods: This study employed transcriptome analysis to investigate host–pathogen interactions by analyzing gene expression changes in NDV-infected chicken embryos’ lungs. Result: RNA-Seq reads were aligned with the chicken reference genome (Galgal7), revealing 594 differentially expressed genes: 264 upregulated and 330 downregulated. The most overexpressed genes, with logFC between 8.15 and 8.75, included C8A, FGG, PIT54, FETUB, APOC3, and FGA. Notably, downregulated genes included BPIFB3 (−4.46 logFC) and TRIM39.1 (−4.26 logFC). The analysis also identified 29 novel transcripts and 20 lncRNAs that were upregulated. Gene Ontology and KEGG pathways’ analyses revealed significant alterations in gene expression related to immune function, metabolism, cell cycle, nucleic acid processes, and mitochondrial activity due to NDV infection. Key metabolic genes, such as ALDOB (3.27 logFC), PRPS2 (2.66 logFC), and XDH (2.15 logFC), exhibited altered expression patterns, while DCK2 (−1.99 logFC) and TK1 (−2.11 logFC) were also affected. Several immune-related genes showed significant upregulation in infected lung samples, including ALB (6.15 logFC), TLR4 (1.86 logFC), TLR2 (2.79 logFC), and interleukin receptors, such as IL1R2 (3.15 logFC) and IL22RA2 (1.37 logFC). Conversely, genes such as CXCR4 (−1.49 logFC), CXCL14 (−2.57 logFC), GATA3 (−1.51 logFC), and IL17REL (−2.93 logFC) were downregulated. The higher expression of HSP genes underscores their vital role in immune responses. Conclusion: Comprehension of these genes’ interactions is essential for regulating viral replication and immune responses during infections, potentially aiding in the identification of candidate genes for poultry breed improvement amidst NDV challenges.
Mass Spectrometry Imaging Reveals Spatial Metabolic Alterations and Salidroside’s Effects in Diabetic Encephalopathy
Authors: Cheng Shuohan , Meng Xianyue , Wang Zixuan , Lan Tianfang , Zhou Zhi , Wang Zhonghua , Abliz Zeper
Published: December 2024

Background: Diabetic encephalopathy (DE) is a neurological complication of diabetes marked by cognitive decline and complex metabolic disturbances. Salidroside (SAL), a natural compound with antioxidant and neuroprotective properties, has shown promise in alleviating diabetic complications. Exploring the spatial metabolic reprogramming in DE and elucidating SAL’s metabolic effects are critical for deepening our understanding of its pathogenesis and developing effective therapeutic strategies. Methods: Air-flow-assisted desorption electrospray ionization–mass spectrometry imaging (AFADESI-MSI) was employed to investigate spatial metabolic alterations in the brains of db/db mice, a spontaneous DE model. The mice were treated with SAL (30 and 150 mg/kg, orally) for 12 weeks. Differential metabolites were identified and characterized using high-resolution mass spectrometry and validated against public databases. Results: Our AFADESI-MSI analysis revealed significant changes in 26 metabolites in the brains of DE mice compared to the controls. These metabolic changes indicated disruptions in glucose, glutamate-glutamine, nucleotide, lipid, choline, aspartate, and L-carnitine metabolism. Notably, glucose 6-phosphate (G6P), glutamine, adenosine, L-carnitine, and choline exhibited similar trends in both db/db mice and STZ-induced rat models of DE, suggesting their potential as reliable biomarkers. Twelve weeks of SAL treatment demonstrated a positive regulatory effect on glucose metabolism, the glutamate–glutamine cycle, and lipid metabolism. Conclusions: This study identifies key metabolic alterations in DE and demonstrates the therapeutic potential of SAL in modulating these disturbances, offering valuable insights for targeted interventions in diabetic complications.