bluuebunny/crossref_metadata_2025 huggingface dataset:
Noise Cancellation Method for Mud Pulse Telemetry Based on Discrete Fourier Transform
Authors: Zhang Jingchen , Sha Zitong , Tu Xingbin , Zhang Zhujun , Zhu Jiang , Wei Yan , Qu Fengzhong
Published: January 2025

Mud pulse telemetry (MPT) systems are widely recognized for their effectiveness and are most commonly used to transmit downhole data to the surface in real time. These data facilitate the drilling process and make it more cost-efficient. In MPT, the mud channel presents a challenging communication environment, primarily due to various sources of noises, with pump noise being the most dominant. In this paper, a noise cancellation method based on discrete Fourier transform (DFT) is proposed for demodulation under a low signal-to-noise ratio, eliminating the pump noise generated by two pumps with a single sensor during drilling. The method employs DFT to estimate the noise spectrum, subtracts noises from the received signal, and performs an inverse transformation to reconstruct the original signal estimation. The effectiveness of the proposed method is evaluated through a simulation analysis and field experiments. The simulation results indicate that the major components of multiple pump noises could be successfully eliminated. The field experiment results demonstrate that the demodulation of the received data achieves advanced data rate communication and a low bit error rate (BER) in a 3000 m drilling system.
Research on the Overall Design and Water Entry Simulation of Cross-Media Unmanned Underwater Vehicles
Authors: Li Wenye , Wu Wuwei , Miao Quanming , Wu Jiahu
Published: January 2025

Novel cross-media vehicles can operate efficiently in different media where water entry is a critical process. In this paper, a water–air cross-media unmanned vehicle is designed and its hydrodynamic characteristics during water entry are studied. With the use of STARCCM, the movement of the vehicle during water entry was simulated with the adoption of a VOF multiphase flow model and a Schnerr–Sauer cavitation model and its accuracy was tested. The flow field characteristics of the vehicle under common operating conditions, as well as the influence of the initial water entry speed and angle on the motion state and the force endured by the vehicle under different operating conditions, were simulated. The results show that the overall operating attitude of the vehicle is stable, and the influence of the water entry speed is more significant than that of the water entry angle. The research results provide a theoretical basis and technical support for the design and application of cross-media vehicles, helping to promote cross-media navigation technology.
A Study on the Limitations of Green Alternative Fuels in Global Shipping in the Foreseeable Future
Authors: Emblemsvåg Jan
Published: January 2025

Shipping carries over 80% of global trade volumes and emits 3% of global greenhouse gas emissions, but it is hard to abate due to the simple fact that ships require a lot of energy and move around. Therefore, a large amount of research and development is poured into understanding the choices of alternative fuels and developing new technologies. Unfortunately, much of the work and policies derived, therefore, seem to rest on a hidden assumption that a relevant amount of green alternative fuel will be available, but that assumption does not stand up to scrutiny on a global level. For example, the results show that decarbonizing global shipping using green ammonia produced from renewable energy sources will require 3.7 times the total EU-27 power production in 2022. The purpose and novelty of this paper are to offer a clear rationale for the correct contextualization of research and development on curbing greenhouse gas emissions from global shipping and individual shipping segments to avoid overpromising and underdelivering.
Collaborative Transport Strategy for Dual AGVs in Smart Ports: Enhancing Docking Accuracy in No-Load Formations
Authors: Zhang Qiang , Li Wenfeng , Guo Long , Qi Xiaohang
Published: January 2025

To enhance the adaptability of automated guided vehicles (AGVs) in port operations, this paper proposes a novel collaborative transport strategy for dual AGVs. This study focuses on reducing formation completion time, improving motion safety, and enhancing pose accuracy at the docking point for no-load dual AGVs, which is the first phase of the transport strategy. To implement this strategy, the sizes of the existing AGVs are adjusted, and a hybrid collaborative control framework is designed. This framework includes a feedback mechanism based on the leader–follower formation model, along with a closed-loop controller utilizing the sliding mode control algorithm. Finally, simulation and physical tests based on real port data verify the proposed strategy’s effectiveness. The results show it significantly enhances the dual AGVs’ motion safety and docking accuracy, providing new insights for smart port development.
Design and Simulation of an Automatic Alignment System for Ship Multi-Support Shafting
Authors: Zhang Jun , Deng Yibin , Gao Guozhang , Zhu Hanhua
Published: January 2025

The current shafting alignment process primarily relies on manual adjustments, resulting in low efficiency and limited precision. This study designs an automatic alignment system for multi-support shafting to improve alignment efficiency and accuracy, advancing the development of intelligent systems. The overall design of the automatic alignment system is proposed, including the establishment of shafting and actuator models. The alignment performance of two control strategies under different shafting deviations is validated through simulations. The results indicate that both the full-state feedback control strategy and the model predictive control strategy can regulate bearing load errors to within 1%. Compared to manual alignment, both strategies demonstrate significantly higher efficiency. The proposed automatic alignment system is feasible and lays a foundation for the development of high-precision shafting alignment systems.
Advanced Control for Shipboard Cranes with Asymmetric Output Constraints
Authors: Cao Mingxuan , Xu Meng , Gao Yongqiao , Wang Tianlei , Deng Anan , Liu Zhenyu
Published: January 2025

Considering the anti-swing control and output constraint problems of shipboard cranes, a nonlinear anti-swing controller based on asymmetric barrier Lyapunov functions (BLFs) is designed. First, model transformation mitigates the explicit effects of ship roll on the desired position and payload fluctuations. Then, a newly constructed BLF is introduced into the energy-based Lyapunov candidate function to generate nonlinear displacement and angle constraint terms to control the rope length and boom luffing angle. Among these, constraints with positive bounds are effectively handled by the proposed BLF. For the swing constraints of the unactuated payload, a carefully designed relevant constraint term is embedded in the controller by constructing an auxiliary signal, and strict theoretical analysis is provided by using a reductio ad absurdum argument. Additionally, the auxiliary signal effectively couples the boom and payload motions, thereby improving swing suppression performance. Finally, the asymptotic stability is proven using LaSalle’s invariance principle. The simulation comparison results indicate that the proposed method exhibits satisfactory performance in swing suppression control and output constraints. In all simulation cases, the payload swing angle complies with the 3° constraint and converges to the desired range within 6 s. This study provides an effective solution to the control challenges of shipboard crane systems operating in confined spaces, offering significant practical value and applicability.
Unsupervised Classification of Global Temperature Profiles Based on Gaussian Mixture Models
Authors: Ye Xiaotian , Zhou Weifeng
Published: January 2025

Understanding ocean temperature distribution is vital for ocean stratification, currents, and marine ecosystems. This study analyzed the global 0.5-degree ocean temperature dataset from the Chinese Academy of Sciences Marine Data Center (July 2020) to identify regional temperature patterns. After standardizing the data, Principal Component Analysis (PCA) reduced the dimensionality from 32 to 7, preserving key temperature variations. A Gaussian Mixture Model (GMM) determined that 18 classifications were optimal by evaluating the variance and category weights. Applying GMM to the reduced data identified 18 distinct temperature distribution patterns across various marine environments, including polar currents, warm current mixing zones, ocean fronts, and enclosed basins, each with unique geographical and physical characteristics. Most classifications showed high posterior probabilities, indicating model accuracy, though lower probabilities were observed in complex regions like the Indian Ocean. The results highlight the significant roles of ocean currents, climatic phenomena, and ecological factors in temperature distribution, providing insights for ocean circulation studies, climate modeling, and marine biodiversity conservation. Future research should enhance the model accuracy by optimizing the parameters, expanding data coverage, integrating additional features, and combining marine observations with climate models to better understand ocean temperature patterns and their global climate impacts.
Phytophthora Species and Their Associations with Chaparral and Oak Woodland Vegetation in Southern California
Authors: Fajardo Sebastian N. , Bourret Tyler B. , Frankel Susan J. , Rizzo David M.
Published: January 2025

Evidence of unintended introductions of Phytophthora species into native habitats has become increasingly prevalent in California. If not managed adequately, Phytophthora species can become devastating agricultural and forest plant pathogens. Additionally, California’s natural areas, characterized by a Mediterranean climate and dominated by chaparral (evergreen, drought-tolerant shrubs) and oak woodlands, lack sufficient baseline knowledge on Phytophthora biology and ecology, hindering effective management efforts. From 2018 to 2021, soil samples were collected from Angeles National Forest lands (Los Angeles County) with the objective of better understanding the diversity and distribution of Phytophthora species in Southern California. Forty sites were surveyed, and soil samples were taken from plant rhizospheres, riverbeds, and off-road vehicle tracks in chaparral and oak woodland areas. From these surveys, fourteen species of Phytophthora were detected, including P. cactorum (subclade 1a), P. multivora (subclade 2c), P. sp. cadmea (subclade 7a), P. taxon ‘oakpath’ (subclade 8e, first reported in this study), and several clade-6 species, including P. crassamura. Phytophthora species detected in rhizosphere soil were found underneath both symptomatic and asymptomatic plants and were most frequently associated with Salvia mellifera, Quercus agrifolia, and Salix sp. Phytophthora species were present in both chaparral and oak woodland areas and primarily in riparian areas, including detections in off-road tracks, trails, and riverbeds. Although these Mediterranean ecosystems are among the driest and most fire-prone areas in the United States, they harbor a large diversity of Phytophthora species, indicating a potential risk for disease for native Californian vegetation.
Spatiotemporal Variation and Driving Factors of Carbon Sequestration Rate in Terrestrial Ecosystems of Ningxia, China
Authors: Zhang Yi , Cheng Chunxiao , Wang Zhihui , Hai Hongxin , Miao Lulu
Published: January 2025

This study investigates the spatiotemporal variation characteristics and influencing factors of an ecosystem’s carbon sequestration rate (CSR) in the Ningxia region from 2001 to 2023, providing scientific evidence for assessing the regional carbon sequestration capacity and formulating carbon neutrality policies. Based on ground observation data and multimodal datasets, the optimal machine learning model (EXT) was used to invert a 30 m high-resolution vegetation and soil carbon density dataset for Ningxia from 2000 to 2023. Annual variation analysis and geographical detector methods were employed to assess the spatiotemporal distribution characteristics of the CSR from 2001 to 2023 and identify the primary influencing factors. The results show that from 2001 to 2023, the CSR of the Ningxia ecosystem exhibits a spatial distribution pattern characterized by higher values in the south and lower values in the north, with a mean value of 21.95 gC·m−2, and an overall fluctuating increasing trend, with an annual growth rate of 0.53 gC·m−2 a−1. Significant differences in the CSR exist across different ecological regions. In terms of land use types, the ranking of carbon sequestration capacity is forest > farmland > grassland > barren, while the ranking of the carbon sequestration enhancement capacity is farmland > forest > grassland > barren. Among land use change types, the carbon sequestration enhancement capacity significantly increased when grassland was converted to forest or shrubland, farmland to forest–grassland, and bare land to forest–grassland, with increases of 42.9%, 9.2%, and 34.6%, respectively. The NDVI is the primary driver of CSR spatiotemporal variation, while the interaction between the Enhanced Vegetation Index (EVI) and soil bulk density has a more significant explanatory power for CSR spatial differentiation. This study shows that ecological restoration projects, such as the conversion of cropland to forest (or grassland) and protective farmland measures, play a significant role in enhancing the carbon sequestration capacity in Ningxia.
The Role of Environmental Factors on Grammatical Development in French–English Bilinguals Attending a Dual Language Programme in France
Authors: Cohen Cathy , Quirk Erin
Published: January 2025

This mixed methods study explores the effects of cumulative exposure, age of onset of acquisition (AO), parent proficiency and richness of the language environment on the grammatical development in French and English of 49 French–English bilingual children who were acquiring the languages either simultaneously (2L1) or successively (cL2). Participants (24 girls) were in 1st grade (M = 6;4, n = 20) or 5th grade (M = 10;4, n = 29), attending a state school in France, in a French–English bilingual programme. Production data come from a narrative task in each language. Parent questionnaires were used to explore environmental factors. Results show, first, that children’s age and parent proficiency were positive predictors of grammatical accuracy in English, while in French only cumulative exposure was a positive predictor. Secondly, exposure showed a stronger relationship with grammatical accuracy in cL2 children; however, only in French, the language in which children made more errors overall. Finally, we found that both 2L1 and cL2 children made gender errors, an early-acquired structure in French. A qualitative analysis of errors with gender highlights, first, the importance of language output for grammatical development, even for children receiving substantial language input and, second, the role of home factors which play a more important role than community language use in shaping grammatical development. This study underscores the complex, interconnected nature of experiential effects on bilingual grammatical development in each language.
Temperature Characteristics of Axle-Box Bearings Under Wheel Flat Excitation
Authors: Luo Yaping , Zhang Fan , Wang Zhiwei , Yang Chen , Zhang Weihua , Gu Fengshou
Published: January 2025

The high-amplitude and high-frequency wheel–rail impacts excited by wheel flat result in severe contact friction in axle-box bearing (ABB), and the friction can cause a temperature rise or even structural damage of ABB. To this end, a thermal analysis model considering the vehicle operation environment is proposed to analyze the temperature characteristics of ABB. Various coupling dynamics effects between the vehicle–track system and ABB are synergistically integrated. The heat conduction, convection, and radiation between the various components of ABB are also integrated into the thermal analysis modeling. By the field tests, the accuracy of the ABB thermal model is validated. The results obtained through the model simulation show that the ABB temperature increases with vehicle speed and wheel flat length, and the ABB temperature at the outside row is higher than that at the inside row. Moreover, the temperature of the roller, cage, inner ring, outer ring, and axle box increases following an ascending order. Specifically, the temperature at the small end of the roller is higher than that at the large end. The findings of this study can provide engineering guidelines for the condition monitoring of ABBs.
Joint Wear Prediction and Experiments Considering the Influences of Coating and Spherical Joint Clearances
Authors: Jing Qian , Geng Baolong
Published: January 2025

In recent years, many scholars have carried out a large number of theoretical studies on mechanism systems with joint clearances. Some scholars have conducted relevant experiments with simple planar mechanisms, for example, which have proved the feasibility and applicability of the numerical dynamics calculation method and different contact force models to a certain extent. In order to verify the correctness of the theoretical analysis method of the system dynamics considering coating and joint clearances in the previous stage, this paper independently designed and built the RSSP experimental platform of the spatial four-bar mechanism by taking the shear fork mechanism of the soybean picking and separating machine in farming operations, and measured the dynamic changes in the execution components and the wear depth of the spherical shell surface in different working conditions. The effectiveness of the coating on alleviating vibration, reducing joint wear, and extending the working life of the system mechanism was verified. The experimental conclusions provide strong data support for the subsequent effective and long-life operation of the soybean picking and sorting integrated machine.
Enhancing Catalytic Performance with Ni Foam-Coated Porous Ni Particles via 1-Butene Hydrogenation
Authors: Park Dahee , Yun Jung-Yeul , Koo Hye Young , Kim Yuchan
Published: January 2025

The efficient hydrogenation of 1-butene is an industrially significant reaction for producing fuels and value-added chemicals. However, achieving high catalytic efficiency and stability remains challenging, particularly for cost-effective materials, such as Ni. In this study, we developed a porous Ni-coated Ni foam catalyst by electrostatic spray deposition to address these challenges. The catalyst exhibited a turnover frequency approximately 10 times higher than that of either porous Ni or Ni foam alone. This enhancement was attributed to the formation of interfacial active sites, which facilitated improved reactant adsorption and activation during hydrogenation. The electrostatic spray deposition technique ensured a uniform and controlled coating, enabling precise engineering of the catalyst structure and interface. The post-deposition heat treatment was further optimized to enhance structural integrity and catalytic performance. This study highlights the importance of interface engineering and structural optimization in catalyst design and provides valuable insights into the development of efficient Ni-based catalysts for industrial hydrogenation applications. These findings emphasize the potential of electrostatic spray deposition as a versatile method for fabricating advanced catalytic systems.
Temperature Uniformity Control of 12-Inch Semiconductor Wafer Chuck Using Double-Wall TPMS in Additive Manufacturing
Authors: Park Sohyun , Lee Jaewook , Lee Seungyeop , Sung Jihyun , Jung Hyungug , Lee Ho , Kim Kunwoo
Published: January 2025

In semiconductor inspection equipment, a chuck used to hold a wafer is equipped with a cooling or heating system for temperature uniformity across the surface of the wafer. Surface temperature uniformity is important for increasing semiconductor inspection speed. Triply periodic minimal surfaces (TPMSs) are proposed to enhance temperature uniformity. TPMSs are a topic of increasing research in the field of additive manufacturing and are a type of metamaterial inspired by nature. TPMSs are periodic surfaces with no intersections. Their continuous curve offers self-support during the additive manufacturing process. This structure enables the division of a single space into two domains. As a result, the heat transfer area per unit volume is larger than that of general lattice structures, leading to a superior heat transfer performance. This paper proposes a new structure called a double-wall TPMS. The process of creating a double-walled TPMS by adjusting the thickness of the sheet TPMS was investigated, and its thermal performance was studied. Finally, a double-wall TPMS was applied to the chuck. The optimal designs for the diamond and gyroid structures exhibited a difference in surface temperature uniformity of 0.23 °C and 0.66 °C, respectively. Accordingly, the models optimized with the double-wall TPMS are proposed.
Structure and Properties of Al–CNT-Based Composites Manufactured by Different Methods: A Brief Review
Authors: Nurguzhin Marat , Janikeyev Marat , Omarbayev Myrzakhan , Yermakhanova Azira , Meiirbekov Mohammed , Zhumakhanov Miras , Keneshbekova Aruzhan , Atamanov Meiram , Akylbayeva Aigerim , Lesbayev Aidos , Yerezhep Darkhan
Published: January 2025

Aluminum–carbon nanotube (Al–CNT) composites represent a cutting-edge class of materials characterized by their exceptional mechanical, thermal, and electrical properties, making them highly promising for aerospace, automotive, electronics, and energy applications. This review systematically examines the impact of various fabrication methods, including conventional powder metallurgy, diffusion and reaction coupling, as well as adhesive and reaction bonding on the microstructure and performance of Al–CNT composites. The analysis emphasizes the critical role of CNT dispersion, interfacial bonding, and the formation of reinforcing phases, such as Al4C3 and Al2O3, in determining the mechanical strength, wear resistance, corrosion resistance, and thermal stability of these materials. The challenges of CNT agglomeration, high production costs, and difficulties in controlling interfacial interactions are highlighted alongside potential solutions, such as surface modifications and reinforcement strategies. The insights presented aim to guide future research and innovation in this rapidly evolving field.
An Evaluation Method for the Skeleton Model Based on Function–Behavior–Structure Correlation Analysis
Authors: Liu Sichao , Nan Shaoke , Tian Ling
Published: January 2025

The skeleton model is an essential tool to support the top-down design of complex products, and the rationality of its design has a significant influence on the detailed design of products. However, the current skeleton models of complex products are mainly designed based on experience, and there is no practical method to judge the rationality of the skeleton model design. This study conducts a component correlation analysis of the skeleton model of complex products. It proposes a method for clustering analysis and evaluating multi-level skeleton models based on the transitive closure method. The effectiveness of the method is verified through a case study of a rocket nose cone’s skeleton model. This method provides a scientific analysis method for designers to establish a reasonable skeleton model. In addition, the knowledge description of the skeleton model established in this study lacks sufficient flexibility, and the time complexity of cluster analysis needs to be reduced.
Benchmarking with a Language Model Initial Selection for Text Classification Tasks
Authors: Riyadi Agus , Kovacs Mate , Serdült Uwe , Kryssanov Victor
Published: January 2025

The now-globally recognized concerns of AI’s environmental implications resulted in a growing awareness of the need to reduce AI carbon footprints, as well as to carry out AI processes responsibly and in an environmentally friendly manner. Benchmarking, a critical step when evaluating AI solutions with machine learning models, particularly with language models, has recently become a focal point of research aimed at reducing AI carbon emissions. Contemporary approaches to AI model benchmarking, however, do not enforce (nor do they assume) a model initial selection process. Consequently, modern model benchmarking is no different from a “brute force” testing of all candidate models before the best-performing one could be deployed. Obviously, the latter approach is inefficient and environmentally harmful. To address the carbon footprint challenges associated with language model selection, this study presents an original benchmarking approach with a model initial selection on a proxy evaluative task. The proposed approach, referred to as Language Model-Dataset Fit (LMDFit) benchmarking, is devised to complement the standard model benchmarking process with a procedure that would eliminate underperforming models from computationally extensive and, therefore, environmentally unfriendly tests. The LMDFit approach draws parallels from the organizational personnel selection process, where job candidates are first evaluated by conducting a number of basic skill assessments before they would be hired, thus mitigating the consequences of hiring unfit candidates for the organization. LMDFit benchmarking compares candidate model performances on a target-task small dataset to disqualify less-relevant models from further testing. A semantic similarity assessment of random texts is used as the proxy task for the initial selection, and the approach is explicated in the context of various text classification assignments. Extensive experiments across eight text classification tasks (both single- and multi-class) from diverse domains are conducted with seven popular pre-trained language models (both general-purpose and domain-specific). The results obtained demonstrate the efficiency of the proposed LMDFit approach in terms of the overall benchmarking time as well as estimated emissions (a 37% reduction, on average) in comparison to the conventional benchmarking process.
Identification of Novel LCN2 Inhibitors Based on Construction of Pharmacophore Models and Screening of Marine Compound Libraries by Fragment Design
Authors: Zheng Ningying , Li Xuan , Zhou Nan , Luo Lianxiang
Published: January 2025

LCN2, a member of the lipocalin family, is associated with various tumors and inflammatory conditions. Despite the availability of known inhibitors, none have been approved for clinical use. In this study, marine compounds were screened for their ability to inhibit LCN2 using pharmacophore models. Six compounds were optimized for protein binding after being docked against the positive control Compound A. Two compounds showed promising results in ADMET screening. Molecular dynamics simulations were utilized to predict binding mechanisms, with Compound 69081_50 identified as a potential LCN2 inhibitor. MM-PBSA analysis revealed key amino acid residues that are involved in interactions, suggesting that Compound 69081_50 could be a candidate for drug development.
Bioactive Angucyclines/Angucyclinones Discovered from 1965 to 2023
Authors: Liu Hai-Shan , Chen Hui-Ru , Huang Shan-Shan , Li Zi-Hao , Wang Chun-Ying , Zhang Hua
Published: January 2025

Angucyclines/angucyclinones, a class of polyketides with diverse chemical structures, display various bioactivities including antibacterial or antifungal, anticancer, anti-neuroinflammatory, and anti-α-glucosidase activities. Marine and terrestrial microorganisms have made significant contributions to the discovery of bioactive angucyclines/angucyclinones. This review covers 283 bioactive angucyclines/angucyclinones discovered from 1965 to 2023, and the emphasis is on the biological origins, chemical structures, and biological activities of these interesting natural products.
Ventilator-Associated Pneumonia After Cardiac Arrest and Prevention Strategies: A Narrative Review
Authors: Shanmugavel Geetha Harinivaas , Teo Yi Xiang , Ravichandran Sharmitha , Lal Amos
Published: January 2025

Background and Objectives: Ventilator-associated pneumonia (VAP) poses a significant threat to the clinical outcomes and hospital stays of mechanically ventilated patients, particularly those recovering from cardiac arrest. Given the already elevated mortality rates in cardiac arrest cases, the addition of VAP further diminishes the chances of survival. Consequently, a paramount focus on VAP prevention becomes imperative. This review endeavors to comprehensively delve into the nuances of VAP, specifically in patients requiring mechanical ventilation in post-cardiac arrest care. The overarching objectives encompass (I) exploring the etiology, risk factors, and pathophysiology of VAP, (II) delving into available diagnostic modalities, and (III) providing insights into the management options and recent treatment guidelines. Methods: A literature search was conducted using PubMed, MEDLINE, and Google Scholar databases for articles about VAP and Cardiac arrest. We used the MeSH terms “VAP”, “Cardiac arrest”, “postcardiac arrest syndrome”, and “postcardiac arrest syndrome”. The clinical presentation, diagnostic, and management strategies of VAP were summarized, and all authors reviewed the selection and decided which studies to include. Key Content and Findings: The incidence and mortality rates of VAP exhibit significant variability, yet a recurring pattern emerges, marked by prolonged hospitalization and exacerbated clinical outcomes. This pattern is attributed to the elevated incidence of drug-resistant infections and the delayed initiation of antimicrobial treatment. This review focuses on VAP, aiming to offer valuable insights into the efficient identification and management of this fatal complication in post-cardiac arrest patients. Conclusion: The prognosis for survival after cardiac arrest is already challenging, and the outlook becomes even more daunting when complicated by VAP. The timely diagnosis of VAP and initiation of antibiotics pose considerable challenges, primarily due to the invasive nature of obtaining high-quality samples and the time required for speciation and identification of antimicrobial sensitivity. The controversy surrounding prophylactic antibiotics persists, but promising new strategies have been proposed; however, they are still awaiting well-designed clinical trials.
Influence of Geometrical Design on Defect Formation of Commercial Al-Si-Cu-Mg Alloy Fabricated by High-Pressure Diecasting: Structural Observation and Simulation Validation
Authors: Bahanan Warda , Fatimah Siti , Kim Dong-Ju , Widiantara I Putu , Kang Jee-Hyun , Ko Young Gun
Published: January 2025

Near-net-shaped metal products manufactured by high-pressure diecasting (HPD) encountered more or less critical failure during operation, owing to the development of micro-defects and structural inhomogeneity attributed to the complexity of geometrical die design. Because the associated work primarily relies on technical experience, it is necessary to perform the structural analysis of the HPDed component in comparison with simulation-based findings that forecast flow behavior, hence reducing trial and error for optimization. This study validated the fluidity and solidification behaviors of a commercial-grade Al-Si-Cu-Mg alloy (ALDC12) that is widely used in electric vehicle housing parts using the ProCAST tool. Both experimental and simulation results exhibited that defects at the interface of a compact mold filling were barely detected. However, internal micro-pores were seen in the bolt region, resulting in a 17.27% drop in micro-hardness compared to other parts, for which the average values from distinguished observation areas were 111.24 HV, 92.03 HV, and 103.87 HV. The simulation aligns with structural observations on defect formation due to insufficient fluidity in local geometry. However, it may underestimate the cooling rate under isothermal conditions. Thus, the simulation used in this work provides reliable predictions for optimizing HPD processing of the present alloy.
Skeletal Site-Specific Lipid Profile and Hematopoietic Progenitors of Bone Marrow Adipose Tissue in Patients Undergoing Primary Hip Arthroplasty
Authors: Trivanović Drenka , Vujačić Marko , Arsić Aleksandra , Kukolj Tamara , Rajković Milica , Bogosavljević Nikola , Baščarević Zoran , Maljković Ružičić Mirjana , Kovačević Jovana , Jauković Aleksandra
Published: January 2025

Background/Objectives: Bone marrow adipose tissue (BMAT) has been described as an important biomechanic and lipotoxic factor with negative impacts on skeletal and hematopoietic system regeneration. BMAT undergoes metabolic and cellular adaptations with age and disease, being a source of potential biomarkers. However, there is no evidence on the lipid profile and cellularity at different skeletal locations in osteoarthritis patients undergoing primary hip arthroplasty. Methods: Acetabular and femoral bone marrow (BM) and gluteofemoral subcutaneous adipose tissue (gfSAT) were obtained from matched patients undergoing hip replacement surgery. BM, BMAT, and gfSAT were explored at the levels of total lipids, fatty acids, and cells by using thin-layerand gas chromatography, ex vivo cellular assays, and flow cytometry. Results: BMAT content was significantly higher in femoral than in acetabular BM. Total lipid analyses revealed significantly lower triglyceride content in femoral than in acetabular BMAT and gfSAT. Frequencies of saturated palmitic, myristic, and stearic acids were higher in femoral than in acetabular BMAT and gfSAT. The content of CD45+CD34+ cells within femoral BMAT was higher than in acetabular BMAT or gfSAT. This was associated with a higher incidence of total clonogenic hematopoietic progenitors and late erythroid colonies CFU-E in femoral BMAT when compared to acetabular BMAT, similar to their BM counterparts. Conclusions: Collectively, our results indicate that the lipid profiles of hip bone and femoral BMAT impose significantly different microenvironments and distributions of cells with hematopoietic potential. These findings might bring forth new inputs for defining BMAT biology and setting novel directions in OA disease investigations.
The Metabolome Characteristics of Aerobic Endurance Development in Adolescent Male Rowers Using Polarized and Threshold Model: An Original Research
Authors: Kong Fanming , Zhu Miaomiao , Pan Xinliang , Zhao Li , Yang Sanjun , Zhuo Jinyuan , Peng Cheng , Li Dongkai , Mi Jing
Published: January 2025

Objective: This study aimed to explore the molecular response mechanisms of differential blood metabolites before and after 8 weeks of threshold and polarized training models using metabolomics technology combined with changes in athletic performance. Methods: Twenty-four male rowers aged 14–16 were randomly divided into a THR group and a POL group (12 participants each). The THR group followed a threshold training model (72%, 24%, and 4% of training time in low-, moderate-, and high-intensity zones, respectively), while the POL group followed a polarized training model (78%, 8%, and 14% training-intensity distribution). Both groups underwent an 8-week training program. Aerobic endurance changes were assessed using a 2 km maximal rowing performance test, and untargeted metabolome analysis was conducted to examine blood metabolomic changes before and after the different training interventions. Aerobic endurance changes were assessed through a 2 km maximal rowing test. Non-targeted metabolomics analysis was employed to evaluate changes in blood metabolome profiles before and after the different training interventions. Results: After 8 weeks of training, both the THR and POL groups exhibited significant improvements in 2 km maximal rowing performance (p < 0.05), with no significant differences between the groups. The THR and POL groups had 46 shared differential metabolites before and after the intervention, primarily enriched in sphingolipid metabolism, glutathione metabolism, and glycine, serine, and threonine metabolism pathways. Nine unique differential metabolites were identified in the THR group, mainly enriched in pyruvate metabolism, glycine, serine, and threonine metabolism, glutathione metabolism, and sphingolipid metabolism. A total of 14 unique differential metabolites were identified in the POL group, predominantly enriched in sphingolipid metabolism, glycine, serine, and threonine metabolism, aminoacyl-tRNA biosynthesis, and glutathione metabolism. Conclusions: The 8-week THR and POL training models demonstrated similar effects on enhancing aerobic performance in adolescent male rowers, indicating that both training modalities share similar blood metabolic mechanisms for improving aerobic endurance. Furthermore, both the THR group and the POL group exhibited numerous shared metabolites and some differential metabolites, suggesting that the two endurance training models share common pathways but also have distinct aspects in enhancing aerobic endurance.
Capsaicin Modulates Ruminal Fermentation and Bacterial Communities in Beef Cattle with High-Grain Diet-Induced Subacute Ruminal Acidosis
Authors: You Wei , Cheng Haijian , Hu Xin , Song Enliang , Jiang Fugui
Published: January 2025

This study was developed with the goal of exploring the impact of capsaicin on ruminal fermentation and ruminal bacteria in beef cattle affected by high-grain diet-induced subacute ruminal acidosis (SARA). In total, 18 healthy Simmental crossbred cattle were randomized into three separate groups (n = 6/group): (1) control diet (CON; forage-to-concentrate ratio = 80:20); (2) high-grain diet (SARA; forage-to-concentrate ratio = 20:80); and (3) high-grain diet supplemented with capsaicin (CAP; 250 mg/cattle/day). The study was conducted over a 60-day period. The results showed that the SARA model was successfully induced in the SARA group with a high-grain diet. Relative to the SARA group, the addition of capsaicin elevated the ruminal pH from 5.40 to 6.36 (p < 0.01), and decreased the total volatile fatty acids (VFAs) from 133.95 to 82.86 mmol/L (p < 0.01), aligning closely with the levels observed in the CON group. The addition of capsaicin increased the alpha diversity of ruminal bacteria relative to the SARA group, as evidenced by a lower Simpson index (p < 0.05), together with increases in the Ace, Chao, and Shannon indices (p < 0.05). Bacteroidota and Firmicutes were the most common phyla across all treatment groups, while Prevotella was the predominant genera. The unique bacterial genera (LDA scores > 4) identified within the SARA group comprised Succinivibrionaceae_UCG-001, Succinivibrio, NK4A214_group, Lachnospiraceae_NK3A20_group, and Ruminococcus, which may serve as potential biomarkers for the diagnosis of SARA. The unique genera associated with the CON group included Rikenellaceae_RC9_gut_group, Prevotellaceae_UCG-003, and U29-B03, while those for the CAP group included Succiniclasticum and Prevotellaceae_UCG-004. In summary, these results suggest that dietary capsaicin supplementation can limit the adverse effects of SARA through the modulation of bacterial communities within the rumen, thus altering ruminal fermentation in beef cattle.
Frozen Fermented Dairy Snacks with Probiotics and Blueberry Bagasse: Stability, Bioactivity, and Digestive Viability
Authors: Hurtado-Romero Alejandra , Zepeda-Hernández Andrea , Cárdenas-Rangel Javier , Aguilar-Márquez Ricardo , Garcia-Amezquita Luis Eduardo , Carrillo-Nieves Danay , García-Cayuela Tomás
Published: January 2025

The demand for healthier snack options has driven innovation in frozen dairy products. This study developed and characterized novel frozen dairy snacks fermented with probiotics (Lactobacillus acidophilus LA5; Lacticaseibacillus rhamnosus GG, and Streptococcus thermophilus BIOTEC003) and containing 2% blueberry bagasse. Four formulations (LA5, LGG, LA5-BERRY, and LGG-BERRY) were analyzed for their nutritional, physicochemical, functional, and sensory properties. High protein content (>17% d.w.) and increased dietary fiber (5.77–5.88% d.w.) were observed in bagasse-containing formulations. Stable technological characteristics were maintained, with melting rates increasing slightly during storage. Probiotic viability remained high (>8.5 log CFU/mL) after freezing and storage at −20 °C for 30 days. Post-simulated digestion, probiotics retained >7.5 log CFU/mL, while blueberry bagasse formulations exhibited significantly higher phenolic content (7.62–8.74 mg/g d.w.) and antioxidant capacity, though anthocyanin content decreased (66–68%). Sensory evaluation by 100 panelists revealed high acceptance scores (>63%), with LGG-BERRY achieving the highest score (78%). These formulations demonstrate significant potential for incorporating probiotics and functional ingredients, providing an innovative solution for probiotic delivery and the sustainable utilization of fruit by-products in the food industry.
Shattering the Amyloid Illusion: The Microbial Enigma of Alzheimer’s Disease Pathogenesis—From Gut Microbiota and Viruses to Brain Biofilms
Authors: Onisiforou Anna , Charalambous Eleftheria G. , Zanos Panos
Published: January 2025

For decades, Alzheimer’s Disease (AD) research has focused on the amyloid cascade hypothesis, which identifies amyloid-beta (Aβ) as the primary driver of the disease. However, the consistent failure of Aβ-targeted therapies to demonstrate efficacy, coupled with significant safety concerns, underscores the need to rethink our approach to AD treatment. Emerging evidence points to microbial infections as environmental factors in AD pathoetiology. Although a definitive causal link remains unestablished, the collective evidence is compelling. This review explores unconventional perspectives and emerging paradigms regarding microbial involvement in AD pathogenesis, emphasizing the gut–brain axis, brain biofilms, the oral microbiome, and viral infections. Transgenic mouse models show that gut microbiota dysregulation precedes brain Aβ accumulation, emphasizing gut–brain signaling pathways. Viral infections like Herpes Simplex Virus Type 1 (HSV-1) and Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) may lead to AD by modulating host processes like the immune system. Aβ peptide’s antimicrobial function as a response to microbial infection might inadvertently promote AD. We discuss potential microbiome-based therapies as promising strategies for managing and potentially preventing AD progression. Fecal microbiota transplantation (FMT) restores gut microbial balance, reduces Aβ accumulation, and improves cognition in preclinical models. Probiotics and prebiotics reduce neuroinflammation and Aβ plaques, while antiviral therapies targeting HSV-1 and vaccines like the shingles vaccine show potential to mitigate AD pathology. Developing effective treatments requires standardized methods to identify and measure microbial infections in AD patients, enabling personalized therapies that address individual microbial contributions to AD pathogenesis. Further research is needed to clarify the interactions between microbes and Aβ, explore bacterial and viral interplay, and understand their broader effects on host processes to translate these insights into clinical interventions.
Characterizing the Contaminant-Adhesion of a Dibenzofuran Degrader Rhodococcus sp.
Authors: Chen Yu , Wei Qingquan , Wang Xudi , Wu Yanan , Fu Changai , Wang Xu , Xu Hangzhou , Li Li
Published: January 2025

The adhesion between dibenzofuran (DF) and degrading bacteria is the first step of DF biodegradation and affects the efficient degradation of DF. However, their efficient adhesion mechanism at the molecular level remains unclear. Therefore, this study first examined the adhesive behaviors and molecular mechanisms of Rhodococcus sp. strain p52 upon exposure to DF. The results showed that the adhesion between strain p52 and DF is mediated by extracellular polymeric substances (EPSs). Compared with sodium acetate as a carbon source, the percentages of glucose and proteins related to electron transfer, toxin–antitoxin, and stress responses were elevated, which were analyzed by polysaccharide composition and proteomics, and the contents of extracellular polysaccharides and proteins were increased. Moreover, biofilm analysis suggested an increase in EPS content, and the change in components increased biofilm yield and promoted loose and porous aggregation between the bacteria; this aggregation caused an increase in the specific surface area in contact with DF. The surface characteristics analysis indicated that the production of EPS reduced the absolute value of the zeta potential and increased the hydrophobicity of strain p52, which was beneficial for the adhesion of strain p52 and DF. These findings help us to enhance the understanding of the adhesion mechanisms and bioremediation of polycyclic aromatic hydrocarbons by degrading bacteria.
Bacterial Isolation from Natural Grassland on Nitrogen-Free Agar Yields Many Strains Without Nitrogenase
Authors: Koirala Amrit , Alshibli Nabilah Ali , Das Bikram K. , Brözel Volker S.
Published: January 2025

Nitrogen inputs for sustainable crop production for a growing population require the enhancement of biological nitrogen fixation. Efforts to increase biological nitrogen fixation include bioprospecting for more effective nitrogen-fixing bacteria. As bacterial nitrogenases are extremely sensitive to oxygen, most primary isolation methods rely on the use of semisolid agar or broth to limit oxygen exposure. Without physical separation, only the most competitive strains are obtained. The distance between strains provided by plating on solid media in reduced oxygen environments has been found to increase the diversity of culturable potential diazotrophic bacteria. To obtain diverse nitrogen-fixing isolates from natural grasslands, we plated soil suspensions from 27 samples onto solid nitrogen-free agar and incubated them under atmospheric and oxygen-reducing conditions. Putative nitrogen fixers were confirmed by subculturing in liquid nitrogen-free media and PCR amplification of the nifH genes. Streaking of the 432 isolates on nitrogen-rich R2A revealed many cocultures. In most cases, only one community member then grew on NFA, indicating the coexistence of nonfixers in coculture with fixers when growing under nitrogen-limited conditions. To exclude isolates able to scavenge residual nitrogen, such as that from vitamins, we used a stringent nitrogen-free medium containing only 6.42 μmol/L total nitrogen and recultured them in a nitrogen-depleted atmosphere. Surprisingly, PCR amplification of nifH using various primer pairs yielded amplicons from only 17% of the 442 isolates. The majority of the nifH PCR-negative isolates were Bacillus and Streptomyces. It is unclear whether these isolates have highly effective uptake systems or nitrogen reduction systems that are not closely aligned with known nitrogenase families. We advise caution in determining the nitrogen fixation ability of plants from growth on nitrogen-free media, even where the total nitrogen is very limited.