bluuebunny/crossref_metadata_2025 huggingface dataset:
Genetic Diversity and Population Structure Analysis of Pinus elliottii Germplasm Resources in Jiangxi Province
Authors: Yi Min , Hu Rong , Huang Wending , Chen Tingxuan , Xie Wenlei , Xie Haiping , Luo Xin , Lai Meng
Published: October 2024

This study aimed to compare and assess the genetic diversity and trends among the introduced family provenance, first-cycle superior trees breeding provenance, and improved-generation superior trees breeding provenance of Pinus elliottii using EST-SSR markers. The goal was to provide a foundation for advanced genetic improvement and sustainable utilization of P. elliottii in Jiangxi Province. A total of 417 individuals were analyzed for their genetic diversity and population structure using 19 pairs of SSR markers. The analysis identified 103 alleles across all the samples, with an average of 5.421 alleles per locus. Compared to other coniferous species, P. elliottii exhibited a moderate to high level of genetic diversity (I = 0.862, He = 0.457). Analysis of the molecular variance (AMOVA) revealed that 97.90% of the genetic variation occurred within provenances, consistent with a low genetic differentiation coefficient (Fst = 0.016 < 0.05) and high gene flow (Nm = 15.715) among provenances. In addition, analysis using STRUCTURE v. 2.3.4 software divided the 417 germplasm samples into two distinct groups, corroborating the results of the principal coordinates analysis (PCoA) and the unweighted pair group method with arithmetic (UPGMA) clustering analysis. Overall, the germplasm resources of P. elliottii exhibited rich genetic diversity, with the majority of the genetic variation occurring within provenances. For the genetic improvement of high-resin-yielding slash pines, breeding programs should prioritize populations with high genetic diversity while carefully selecting superior individuals from within those populations. These findings provide a solid foundation for breeding high-resin-yielding varieties and for future research on the sustainable utilization of these valuable resources.
Stochastic Processes Dominate the Assembly of Soil Bacterial Communities of Land Use Patterns in Lesser Khingan Mountains, Northeast China
Authors: Ding Junnan , Yu Shaopeng
Published: October 2024

To meet the demands of a growing population, natural wetlands are being converted to arable land, significantly impacting soil biodiversity. This study investigated the effects of land use changes on bacterial communities in wetland, arable land, and forest soils in the Lesser Khingan Mountains using Illumina MiSeq 16S rRNA sequencing. Soil physicochemical properties and enzyme activities were measured using standard methods, while microbial diversity was assessed through sequencing analysis. Our findings revealed that forest soils had significantly higher levels of total potassium (2.62 g·kg−1), electrical conductivity (8.22 mS·cm−1), urease (0.18 mg·g−1·d−1), and nitrate reductase (0.13 mg·g−1·d−1), attributed to rich organic matter and active microbial communities. Conversely, arable soils showed lower total potassium (1.94 g·kg−1), reduced electrical conductivity, and suppressed enzyme activities due to frequent tilling and fertilization. Wetland soils exhibited the lowest values primarily due to water saturation, which limits organic matter decomposition and microbial activity. Land use changes notably reduced microbial diversity, with conversion from forest to arable land leading to habitat loss. Forest soils supported higher abundances of Proteobacteria (37.59%) and Actinobacteriota (34.73%), while arable soils favored nitrogen-fixing bacteria. Wetlands were characterized by chemoheterotrophic and anaerobic bacteria. Overall, these findings underscore the profound influence of land use on soil microbial communities and their functional roles, highlighting the need for sustainable management practices.
Assessing the Tribological Impact of 3D Printed Carbon-Reinforced ABS Composite Cylindrical Gears
Authors: Ripeanu Razvan George , Tănase Maria , Portoacă Alexandra Ileana , Diniță Alin
Published: October 2024

The tribological performance of carbon-reinforced acrylonitrile butadiene styrene (ABS) composites is very important in determining their suitability for advanced engineering applications. This study employs response surface methodology (RSM) to evaluate the effects of printing temperature and post-processing annealing on the wear resistance and frictional properties of these composites. A central composite design is used to systematically explore the interaction between these two factors, enabling the development of predictive models for key tribological parameters. The results reveal that both the coefficient of friction (COF) and wear are affected by printing and annealing temperatures, although in a non-linear manner. Moderate printing temperatures and lower annealing temperatures were found to reduce friction and wear, with annealing temperature having a more pronounced effect on wear. To further optimize these responses, the desirability approach was applied for predicting the optimal conditions. The optimal combination of input parameters for minimizing both COF and wear was found to be a printing temperature of 256 °C and an annealing temperature of 126 °C. This research provides valuable insights for optimizing additive manufacturing processes of carbon-reinforced ABS composites, contributing to enhanced material durability in practical applications.
Enhancing Machining Efficiency: Real-Time Monitoring of Tool Wear with Acoustic Emission and STFT Techniques
Authors: Maia Luís Henrique Andrade , Abrão Alexandre Mendes , Vasconcelos Wander Luiz , Júnior Jánes Landre , Fernandes Gustavo Henrique Nazareno , Machado Álisson Rocha
Published: October 2024

Tool wear in machining is inevitable, and determining the precise moment to change the tool is challenging, as the tool transitions from the steady wear phase to the rapid wear phase, where wear accelerates significantly. If the tool is not replaced correctly, it can result in poor machining performance. On the other hand, changing the tool too early can lead to unnecessary downtime and increased tooling costs. This makes it critical to closely monitor tool wear and utilize predictive maintenance strategies, such as tool condition monitoring systems, to optimize tool life and maintain machining efficiency. Acoustic emission (AE) is a widely used technique for indirect monitoring. This study investigated the use of Short-Time Fourier Transform (STFT) for real-time monitoring of tool wear in machining AISI 4340 steel using carbide tools. The research aimed to identify specific wear mechanisms, such as abrasive and adhesive ones, through AE signals, providing deeper insights into the temporal evolution of these phenomena. Machining tests were conducted at various cutting speeds, feed rates, and depths of cut, utilizing uncoated and AlCrN-coated carbide tools. AE signals were acquired and analyzed using STFT to isolate wear-related signals from those associated with material deformation. The results showed that STFT effectively identified key frequencies related to wear, such as abrasive between 200 and 1000 kHz and crack propagation between 350 and 550 kHz, enabling a precise characterization of wear mechanisms. Comparative analysis of uncoated and coated tools revealed that AlCrN coatings reduced tool wear extending tool life, demonstrating superior performance in severe cutting conditions. The findings highlight the potential of STFT as a robust tool for monitoring tool wear in machining operations, offering valuable information to optimize tool maintenance and enhance machining efficiency.
Viologen-Directed Silver-Thiocyanate-Based Photocatalyst for Rhodamine B Degradation in Artificial Seawater
Authors: Zhuang Xueqiang , Huang Xihe , Li Haohong , Lin Tianjin , Gao Yali
Published: October 2024

Photocatalytic degradation is a leading technology for complete mineralization of organic dyes in the ocean. In this work, a new viologen-bearing silver-thiocyanate-based photocatalyst, i.e., {(i-PrV)[Ag2(SCN)4]}n (i-PrV2+ = isopropyl viologen) has been synthesized and structurally determined, with results showing that it can exhibit excellent degradation performance on rhodamine B (RhB) in artificial seawater. The planar i-PrV2+ dications are confined in the free voids of the [Ag2(SCN)4]n2n− layer with a two-dimensional (6,3) mesh, and strong C-H···S hydrogen bonds contribute to its structural stabilization. This photocatalyst was further characterized by powder X-ray diffraction (PXRD), UV-Vis, fluorescence, and photo/electrical responsive measurements, pointing to its application in visible-light-driven catalysis. Interestingly, using this photocatalyst, good photocatalytic degradation performance on rhodamine B in artificial seawater could be observed. The dye pollutant could be degraded with a high degradation ratio of 87.82% in 220 min. This work provides a promising catalyst for organic dye-type ocean pollutant treatments.
Evolution of Microstructures and Mechanical Properties with Tempering Temperature in a Novel Synergistic Precipitation Strengthening Ultra-High Strength Steel
Authors: Liu Yue , Han Shun , Yang Chao , Geng Ruming , Yuan Xiaoyuan , Li Yong , Wang Chunxu
Published: October 2024

The evolution of microstructures and mechanical properties with tempering temperature of a novel 2.5 GPa grade ultra-high strength steel with synergistic precipitation strengthening was investigated. With increasing tempering temperature, the experimental steel initially progressed from ε-carbides to M3C and then to M2C, followed by further coarsening of the M2C carbides and β-NiAl. Concurrently, the martensite matrix gradually decomposed and austenitized. The ultimate tensile strength and yield strength initially increased and subsequently decreased with rising tempering temperature, reaching peak value at 460 and 470 °C, respectively. Conversely, the ductility and toughness initially decreased and then increased with rising tempering temperature, reaching a minimum at 440 °C. The increase in strength was attributed to the secondary hardening effects resulting from carbide evolution and the precipitation of β-NiAl. The subsequent decrease in strength was due to the recovery of martensite and coarsening of precipitates. The decrease in ductility and toughness was linked to the precipitation of M3C, while their subsequent increase was primarily attributed to the dissolution of M3C and an increase in the volume fraction of reverted austenite. The high dislocation density of martensite, the film of reverted austenite, nanoscale M2C carbides, and ultrafine β-NiAl obtained during tempering at 480 °C resulted in the optimal mechanical properties of the experimental steel. The strength contributions from M2C carbides and β-NiAl were 1081 and 597 MPa, respectively.
Solid-State Diffusion Bonding of Aluminum to Copper for Bimetallic Anode Fabrication
Authors: de Prado Javier , Børresen Børre Tore , Utrilla Victoria , Ureña Alejandro
Published: October 2024

The diffusion-bonding technique has been utilized to join various Al alloys (AA1060, AA2024, AA3003) to Cu for bimetallic anode application. This process aims to achieve robust metallic continuity to facilitate electron transfer, while carefully managing the growth of the intermetallic layer at the bonding interface. This control preserves the active volume of aluminum and prevents excessive brittleness of the anode. Optimization efforts have focused on different pressures, surface treatments of parent materials, and bonding parameters (temperature 450–500 °C and time 5–60 min). The optimal conditions identified include low bonding pressures (8 MPa), surface treatment involving polishing followed by chemical cleaning of the surfaces to be bonded, and energetic bonding conditions tailored to each specific aluminum alloy. Preliminary electrochemical characterization via cyclic voltammetry (CV) tests has demonstrated high reversibility intercalation/deintercalation reactions for up to seven cycles. The presence of the different alloying elements appears to contribute significantly to maintaining the high intercalation/deintercalation reaction reversibility without considerable modification of the reaction potentials. This effect may be attributed to alloying elements effectively reducing the overall alloy volume expansion, potentially forming highly reversible ternary/quaternary active phases, and creating a porous reaction layer on the exposed aluminum surface. These factors along with the influence of the Cu parent material collectively reduce the stress during volume expansion, which is the responsible phenomenon of the anode degradation in common Al anodes.
Radiation-Induced Paramagnetic Centers in Meso- and Macroporous Synthetic Opals from EPR and ENDOR Data
Authors: Rodionov Alexander , Latypova Larisa , Mamin Georgy , Gafurov Marat
Published: October 2024

The paramagnetic defects and radiation-induced paramagnetic centers (PCs) in silica opals can play a crucial role in determining the magnetic and electronic behavior of materials and serve as local probes of their electronic structure. Systematic investigations of paramagnetic defects are essential for advancing both theoretical and practical aspects of material science. A series of silica opal samples with different geometrical parameters were synthesized and radiation-induced PCs were investigated by means of the conventional and pulsed X- and W-band electron paramagnetic resonance, and 1H/2H Mims electron-nuclear double resonance. Two groups of PCs were distinguished based on their spectroscopic parameters, electron relaxation characteristics, temperature and time stability, localization relative to the surface of silica spheres, and their origin. The obtained data demonstrate that stable radiation-induced E’ PCs can be used as sensitive probes for the hydrogen-containing fillers of the opal pores, for the development of compact radiation monitoring equipment, and for quantum technologies.
Construction of Akushsky Core Functions Without Critical Cores
Authors: Lutsenko Vladislav , Babenko Mikhail , Deryabin Maxim
Published: October 2024

The residue number system is widely used in cryptography, digital signal processing, image processing systems, and other areas where high-performance computing is required. One of the main tools used in the residue number system is the Akushsky core function. However, its use is limited due to the existence of so-called critical cores. This study aims to develop Akushsky core functions that effectively eliminate the occurrence of critical cores, thereby enhancing their applicability in real-world scenarios. We introduce a fundamental approach to critical core detection that reduces the average time for critical core detection by 99.48% compared to the brute force algorithm. The results of our analysis indicate not only a substantial improvement in the speed of core detection but also an enhancement in the overall performance of systems utilizing the Akushsky core function. Our findings provide important insights into optimizing residue number systems and encourage further exploration into advanced computational techniques within this domain.
Association between Ventilation Disorder and Masticatory Dysfunction in the Korean Adult Population: A Cross-Sectional Study Using Data from the 2019 Korea National Health and Nutrition Examination Survey
Authors: Kim So-Yeong , Lim Sun-A
Published: October 2024

Background and Objectives: Respiratory and periodontal diseases are among the most common diseases affecting humans worldwide. Periodontal disease is a risk factor for aspiration pneumonia and other respiratory diseases. However, the evidence supporting the link between respiratory and periodontal disease is inconclusive and insufficient. Therefore, this study aimed to investigate the relationship between oral disease symptoms and respiratory diseases. Materials and Methods: Adults who underwent oral examinations and lung disease tests were recruited from the 2019 Korea National Health and Nutrition Examination Survey (KNHANES). A total of 14,956 individuals participated in the 2019 KNHANES. Among the 6846 participants who underwent oral examinations, 1320 children and adolescents were excluded. Additionally, of the 4119 adults aged ≥40 years who underwent dual lung function tests, those who did not respond to key independent confounding variables were excluded. The final sample consisted of 2988 adults. Results: Complex sample multivariate logistic regression analysis revealed that the risk of restrictive ventilation disorder was lower in individuals without chewing discomfort compared to individuals with chewing discomfort (odds ratio, 0.68; 95% confidence interval, 0.479–0.996), and the difference was statistically significant. Only one significant difference was observed between the two groups. Conclusions: Chewing discomfort is a major periodontal health-related factor associated with chronic obstructive pulmonary disease (COPD). Although the exact mechanism underlying the relationship between masticatory discomfort and COPD remains unclear, masticatory discomfort is an early symptom of oral diseases. The findings from this study provide additional basic data for the prevention of oral diseases and COPD in Korea.
Utilizing the Postvascular Phase of Contrast-Enhanced Ultrasound to Predict Breast Cancer Lymph Node Metastasis
Authors: Ma Jiuyi , Fu Ying , Chen Xiangmei , Lin Yuxuan , Zeng Lan , Mei Fang , Cui Ligang
Published: October 2024

Background and Objectives: To evaluate the value of the postvascular phase of contrast-enhanced ultrasound (CEUS) in differentiating between benign and metastatic lymph nodes (LNs) in patients with breast cancer (BC). Materials and Methods: This study retrospectively analyzed 96 suspicious LNs in the lymphatic drainage area of the breast from 90 patients with BC. All LNs were assessed by conventional ultrasound (US) and CEUS following intravenous Sonazoid injection. All LNs underwent puncture biopsy, and pathological results were obtained. The correlations between US and CEUS indicators of LNs and LN metastasis (LNM) were analyzed. Results: Of the 96 LNs, 66 were metastatic. Overall, 80.00% (24/30) of the benign LNs exhibited relative hyper-enhancement in the postvascular phase, whereas 96.97% (64/66) of the metastatic LNs exhibited relative hypo-enhancement (p < 0.001). This CEUS finding was highly predictive of metastasis, with a sensitivity of 96.97%, specificity of 80.00%, positive predictive value of 91.43%, negative predictive value of 92.31%, and accuracy of 91.67%. The mean postvascular phase intensity (MPI) was significantly lower for malignant (median MPI, 12 dB) than for benign (median MPI, 75 dB) LNs. The postvascular phase was more sensitive, specific, and accurate than conventional US or the vascular phase of CEUS for the diagnosis of LNM, with an area under the curve of 0.95 (95% confidence interval: 0.89–0.99). Conclusions: Qualitative and quantitative indicators of the postvascular phase of CEUS provide a reliable diagnostic approach to differentiate benign and metastatic LNs in patients with BC.
Differential Effects of Landiolol in Patients with Atrial Fibrillation and Atrial Tachycardia
Authors: Ayabe Kengo , Komiyama Tomoyoshi , Takekawa Hiroyuki , Kang Honsa , Tsumagari Yasuaki , Ito Miwa , Ashikaga Keiichi , Shibata Yoshisato
Published: October 2024

Landiolol, an ultra-short-acting β1-selective blocker, is more effective in controlling heart rate compared with digoxin in patients with atrial tachyarrhythmias and left ventricular dysfunction. However, the effect of atrial tachyarrhythmia type on the effectiveness of landiolol remains unknown. Hence, this study aimed to evaluate the effectiveness of landiolol in patients with atrial fibrillation (AF) and atrial tachycardia (AT), not limited to those with heart failure with a reduced ejection fraction. To this end, we evaluated the efficacy and safety of landiolol in managing tachycardiac AF and tachycardiac atrial flutter/AT in 44 patients with reduced left ventricular function. We found that while landiolol was effective in managing patients with AF and heart failure with a preserved or mid-range ejection fraction, however, it might be more challenging to control heart rate in patients with AT using a similar dosage of landiolol.
Ultrasound-Enhanced Friction Stir Welding of Aluminum Alloy 6082: Advancements in Mechanical Properties and Microstructural Refinement
Authors: Rebrin Marat , Gester Andreas , Ozherelkov Dmitrii , Wächtler Christiane , Sprigode Toni , Mädlow Martin , Wagner Guntram
Published: October 2024

This study examines the effects of ultrasound-enhanced friction stir welding (USE-FSW) on the mechanical properties and microstructural characteristics of aluminum alloy AA6082-T6, commonly used in automotive, aerospace, and construction industries. The investigation included tensile and bending tests, as well as detailed microstructural evaluations using scanning electron microscopy (SEM), electron backscatter diffraction (EBSD), and energy-dispersive X-ray spectroscopy (EDS). The results indicate that USE-FSW led to an approximately 26% increase in tensile strength compared to similar samples produced by conventional friction stir welding (CFSW). Additionally, the elongation at break improved by around 52%, indicating better ductility. Flexural strength also showed a notable improvement of over 70%. Microstructural analysis revealed a finer grain structure in the stir zone, contributing to these mechanical enhancements. However, the changes in texture and grain orientation were relatively modest, as shown by EBSD and Kernel Average Misorientation (KAM) analyses. Overall, USE-FSW offers incremental improvements in weld quality and mechanical performance, making it a promising technique for producing joints with slightly enhanced strength and ductility.
Effects of 10 keV Electron Irradiation on the Performance Degradation of SiC Schottky Diode Radiation Detectors
Authors: Ruan Jinlu , Chen Liang , Zhou Leidang , Du Xue , Wang Fangbao , Zhang Yapeng , Zhao Penghui , Ouyang Xiaoping
Published: October 2024

The silicon carbide (SiC) Schottky diode (SBD) detector in a SiC hybrid photomultiplier tube (HPMT) generates signals by receiving photocathode electrons with an energy of 10 keV. So, the performance of the SiC SBD under electron irradiation with an energy of 10 keV has an important significance for the application of the SiC-HPMT. However, studies on 10 keV radiation effects on the SiC SBDs were rarely reported. In this paper, the performance degradation of the SiC SBDs irradiated by 10 keV electrons at different fluences was investigated. After the irradiation, the forward current of the SiC SBDs increased, and the turn-on voltage decreased with the irradiation fluences until 1.6 × 1016 cm−2. According to the capacitance–voltage (C-V) curves, the effective doping concentration increased slightly after the irradiation, and an obvious discrepancy of C-V curves occurred below 5 V. Moreover, as a radiation detector, the peak position of the α-particles’ amplitude spectrum changed slightly, and the energy resolution was also slightly reduced after the irradiation due to the high collection charge efficiency (CCE) still being larger than 99.5%. In addition, the time response of the SiC SBD to the 50 ns pulsed X-ray was almost not affected by the irradiation. The results indicated that the performance degradation of the SiC SBD irradiated at the fluence of 1.5 × 1017 cm−2 would not result in a deterioration of the properties of the SiC-HPMT and showed an important significance for the supplement of the radiation resistance of the SiC SBD radiation detector.
Assessment of the Risk of Crack Formation at a Hybrid Bonding Interface Using Numerical Analysis
Authors: Le Xuan-Bach , Choa Sung-Hoon
Published: October 2024

Hybrid bonding technology has recently emerged as a promising solution for advanced semiconductor packaging technologies. However, several reliability issues still pose challenges for commercialization. In this study, we investigated the possibility of crack formation caused by chemical mechanical polishing (CMP) defects and the misalignment of the hybrid bonding structure. Crack formation and thermomechanical stress were analyzed for two common hybrid bonding structures with misalignment using a numerical simulation. The effects of annealing temperature and dishing value on changes in the non-bonding area and peeling stress were systematically analyzed. The calculated peeling stresses were compared to the bonding strength of each bonding interface to find vulnerable regions prone to cracking. The non-bonding area in the bonding structure increased with a decreasing annealing temperature and an increasing dishing value. To achieve a sufficient bonding area of more than 90%, the annealing temperature should be greater than 200 °C. During the heating period of the annealing process, the SiCN-to-SiCN bonding interface was the most vulnerable cracking site with the highest peeling stress. An annealing temperature of 350 °C carries a significant risk of cracking. On the other hand, an annealing temperature lower than 250 °C will minimize the chance of cracking. The SiCN-to-SiO2 bonding interface, which has the lowest adhesion energy and a large coefficient of thermal expansion (CTE) mismatch, was expected to be another possible cracking site. During cooling, the SiCN-to-Cu bonding interface was the most vulnerable site with the highest stress. However, the simulated peeling stresses were lower than the adhesion strength of the bonded interface, indicating that the chance of cracking during the cooling process was very low. This study provides insights into minimizing the non-bonding area and preventing crack formation, thereby enhancing the reliability of hybrid bonding structures.
A Cross-Scale Electrothermal Co-Simulation Approach for Power MOSFETs at Device–Package–Heatsink–Board Levels
Authors: Dai Yuxuan , Yao Jiafei , Chen Jing , Qian Qingyou , Zhang Maolin , Zhang Jun , Yao Qing , Huang Chenyang , Sun Mingshun , Guo Yufeng
Published: October 2024

This paper proposes a cross-scale simulation approach for evaluating the steady-state electrothermal performance of power MOSFETs at the device–package–heatsink–board (DPHB) level. A co-simulation framework is designed by employing the iterative process of power loss and chip temperature to bridge the device and package–heatsink–board (PHB) level simulators. As a result, the cross-scale electrothermal coupling effect within multilevel settings is considered. Correspondingly, variation values in chip temperature and temperature-dependent drain current can be obtained at various voltage biases, level settings, and DPHB structural parameters, incorporating cross-level physical insights. The simulation results are compared with existing methods, and their features and limitations are discussed. Additionally, this paper also derives an empirical equation from the co-simulations to characterize the relationship between the drain current and the chip temperature under different operations exactly. A commercial MOSFET with TO-220F packaging is implemented in experiments to extract the chip temperature and drain current in electrothermal equilibrium. The method comparisons and fair agreement among simulations, equations, and measurements presents the proposed approach as generalized and powerful for describing variations in chip temperature and drain current considering from micrometer devices to millimeter packages–heatsinks–PCB boards, thus providing effective support for DPHB-level co-design.
Cross-Kingdom Pathogenesis of Pantoea alfalfae CQ10: Insights from Transcriptome and Proteome Analyses
Authors: Su Jing , Yao Bo , Huang Rong , Liu Xiaoni , Zhang Zhenfen , Zhang Yong
Published: October 2024

In grassland agroecosystems, some plant pathogenic bacteria can cause disease in animals. These strains are known as plant and animal cross-kingdom pathogenic bacteria. In this study, we established an alfalfa root infection model and a mouse model via the gavage administration of the Pantoea alfalfae CQ10 (CQ10) bacterial suspension. It was confirmed that the CQ10 strain caused bacterial leaf blight of alfalfa. Mice inoculated with 0.4 mL of 109 cfu/mL bacterial suspension developed clinical symptoms 48 h later, such as diminished vitality, tendencies to huddle, and lack of appetite, including severe lesions in stomach, liver, kidney, and spleen tissues. CQ10 strains were isolated from mouse feces at different time points of inoculation. Thus, CQ10 is a plant and animal cross-kingdom pathogenic bacterium. Transcriptome and proteome analyses showed that biofilm and iron uptake are important virulence factors of the pathogen CQ10, among which Bap and Lpp regulating biofilm are the key cross-kingdom virulence genes of CQ10. From an evolutionary perspective, insights gained from this dual animal–plant pathogen system may help to elucidate the molecular basis underlying the host specificity of bacterial pathogens. The result provides a theoretical basis for the risk assessment, prevention, and control strategies of new pathogenic bacteria entering a new region.
Cold-Active Lipase from the Ice Cave Psychrobacter SC65A.3 Strain, a Promising Biocatalyst for Silybin Acylation
Authors: Paun Victoria I. , Ion Sabina G. , Gheorghita Giulia R. , Podolean Iunia , Tudorache Madalina , Purcarea Cristina
Published: October 2024

Cold-active lipase from the psychrophilic bacterial strain Psychrobacter SC65A.3 isolated from Scarisoara Ice Cave (Romania) was cloned and characterized as an extremophilic biocatalyst for silybin acylation. Structural analyses highlighted conserved motifs confirming a functional lipase and the presence of primary structure elements for catalysis at low temperatures. The recombinant enzyme (PSL2) heterologously expressed in Escherichia coli was purified in one step by affinity chromatography with a yield of 12.08 ± 1.72 µg L−1 of culture and a specific activity of 20.1 ± 3.2 U mg−1 at 25 °C. Functional characterization of PSL2 showed a neutral (7.2) optimal pH and a high thermal stability up to 90 °C. Also, this lipase was stable in the presence of different organic solvents, with 60% residual activity when using 20% DMSO. Kinetic measurements indicated performant catalytic efficiency of PSL2 for different short and long chain fatty acids, with Km in the mM range. The catalytic activity of PSL2 was assessed for silybin acylation with various fatty acids and fatty acid methyl esters, demonstrating a 90% silybin conversion when methyl decanoate ester was used. This result clearly highlights the biocatalytic capability of this new cold-active lipase.
Hydrophobic Modification of Cellulose Acetate and Its Application in the Field of Water Treatment: A Review
Authors: An Yaxin , Li Fu , Di Youbo , Zhang Xiangbing , Lu Jianjun , Wang Le , Yan Zhifeng , Wang Wei , Liu Mei , Fei Pengfei
Published: October 2024

With the inherent demand for hydrophobic materials in processes such as membrane distillation and unidirectional moisture conduction, the preparation and application development of profiles such as modified cellulose acetate membranes that have both hydrophobic functions and biological properties have become a research hotspot. Compared with the petrochemical polymer materials used in conventional hydrophobic membrane preparation, cellulose acetate, as the most important cellulose derivative, exhibits many advantages, such as a high natural abundance, good film forming, and easy modification and biodegradability, and it is a promising polymer raw material for environmental purification. This paper focuses on the research progress of the hydrophobic cellulose acetate preparation process and its current application in the water-treatment and resource-utilization fields. It provides a detailed introduction and comparison of the technical characteristics, existing problems, and development trends of micro- and nanostructure and chemical functional surface construction in the hydrophobic modification of cellulose acetate. Further review was conducted and elaborated on the applications of hydrophobic cellulose acetate membranes and other profiles in oil–water separation, brine desalination, water-repellent protective materials, and other separation/filtration fields. Based on the analysis of the technological and performance advantages of profile products such as hydrophobic cellulose acetate membranes, it is noted that key issues need to be addressed and urgently resolved for the further development of hydrophobic cellulose acetate membranes. This will provide a reference basis for the expansion and application of high-performance cellulose acetate membrane products in the environmental field.
Rapid Preparation of Platinum Catalyst in Low-Temperature Molten Salt Using Microwave Method for Formic Acid Catalytic Oxidation Reaction
Authors: Zhao Haidong , Hu Xiaoyan , Ling Hongbiao , Li Ji , Wang Weixu , Guo Jingtao , Liu Rui , Lv Chao , Lu Zhen , Guo Yong
Published: October 2024

In this paper, platinum nanoparticles with a size of less than 50 nm were rapidly and successfully synthesized in low-temperature molten salt using a microwave method. The morphology and structure of the product were characterized by SEM, TEM, EDX, XRD, etc. The TEM and SEM results showed that the prepared product was a nanostructure with concave and uniform size. The EDX result indicated that the product was pure Pt, and the XRD pattern showed that the diffraction peaks of the product were consistent with the standard spectrum of platinum. The obtained Pt/C nanoparticles exhibited remarkable electrochemical performance in a formic acid catalytic oxidation reaction (FAOR), with a peak mass current density of 502.00 mA·mg−1Pt and primarily following the direct catalytic oxidation pathway. In addition, in the chronoamperometry test, after 24 h, the mass-specific activity value of the Pt concave NPs/C catalyst (10.91 mA·mg−1Pt) was approximately 4.5 times that of Pt/C (JM) (2.35 mA·mg−1Pt). The Pt/C NPs exhibited much higher formic acid catalytic activity and stability than commercial Pt/C. The microwave method can be extended to the preparation of platinum-based alloys as well as other catalysts.
Metabolomic Analysis of Elymus sibiricus Exposed to UV-B Radiation Stress
Authors: Zhang Fei , Sun Ming , Li Daxu , You Minghong , Yan Jiajun , Bai Shiqie
Published: October 2024

Plants cultivated on the Qinghai-Tibet Plateau (QTP) are exposed to high ultraviolet radiation intensities, so they require effective mechanisms to adapt to these stress conditions. UV-B radiation is an abiotic stress factor that affects plant growth, development, and environmental adaptation. Elymus sibiricus is a common species in the alpine meadows of the QTP, with high-stress resistance, large biomass, and high nutritional value. This species plays an important role in establishing artificial grasslands and improving degraded grasslands. In this study, UV-B radiation-tolerant and UV-B radiation-sensitive E. sibiricus genotypes were subjected to simulated short-term (5 days, 10 days) and long-term (15 days, 20 days) UV-B radiation stress and the metabolite profiles evaluated to explore the mechanism underlying UV-B radiation resistance in E. sibiricus. A total of 699 metabolites were identified, including 11 primary metabolites such as lipids and lipid-like molecules, phenylpropanoids and polyketides, organic acids and their derivatives, and organic oxygen compounds. Principal component analysis distinctly clustered the samples according to the cultivar, indicating that the two genotypes exhibit distinct response mechanisms to UV-B radiation stress. The results showed that 14 metabolites, including linoleic acid, LPC 18:2, xanthosine, and 23 metabolites, including 2-one heptamethoxyflavone, glycyrrhizin, and caffeic acid were differentially expressed under short-term and long-term UV-B radiation stress, respectively. Therefore, these compounds are potential biomarkers for evaluating E. sibiricus response to UV-B radiation stress. Allantoin specific and consistent expression was up-regulated in the UV-B radiation-tolerant genotype, thereby it can be used to identify varieties resistant to UV-B radiation. Different metabolic profiles and UV-B radiation response mechanisms were observed between the UV-B radiation-tolerant and UV-B radiation-sensitive E. sibiricus genotypes. A model for the metabolic pathways and metabolic profiles was constructed for the two genotypes. This metabolomic study on the E. sibiricus response to UV-B radiation stress provides a reference for the breeding of new UV-B radiation-tolerant E. sibiricus cultivars.
Comparison of Different Solid-Phase Microextraction Formats Dedicated to the Analysis of Volatile Compounds—A Comprehensive Study
Authors: Wieczorek Martyna Natalia
Published: October 2024

The coupling of Solid-Phase Microextraction (SPME) technology with gas chromatography (GC) has a well-established and successful history. Traditionally, SPME fibers have been the most popular form thanks to their versatility and the ease with which they can be fully automated. However, alternative geometries for SPME have been developed over the years, beginning with Stir Bar Sorptive Extraction (SBSE) and later evolving into Thin-Film SPME (TF-SPME) devices. Each of these formats offers distinct advantages and disadvantages, which are explored in this study. The primary objective of this study was to comprehensively compare available forms of SPME devices, with a special focus on the advantages of TF-SPME, a novel microextraction method particularly suited for the analysis of odorants in food. The study involved analyzing a standard mixture of 11 key food odorants, representing a range of polarities, to evaluate the efficiency of TF-SPME devices in terms of the number of analytes extracted. Furthermore, four types of TF-SPME devices were compared against each other in both standard mixtures and actual food samples. The final stage of the study employed GCxGC-ToFMS analysis to showcase the potential of the most efficient HLB-TF-SPME device in the non-targeted analysis of complex samples, exemplified by unfiltered wheat beer. This analysis demonstrated the significant capability of HLB-TF-SPME in capturing and identifying a wide range of volatile compounds in complex matrices.
Ball Milling and Magnetic Modification Boosted Methylene Blue Removal by Biochar Obtained from Water Hyacinth: Efficiency, Mechanism, and Application
Authors: Wang Bei , Ma Yayun , Cao Pan , Tang Xinde , Xin Junliang
Published: October 2024

Ball milling is a feasible and promising method of biochar modification that can significantly increase its adsorption ability to methylene blue (MB). This study synthesized nine biochars derived from water hyacinth under different pyrolysis temperatures and modified with ball milling and Fe3O4. The structural properties of the pristine and ball-milled magnetic biochars were investigated and employed to adsorb MB. The results showed that ball milling significantly enhanced the specific surface area, total pore volume, and C-, N-, and O-containing groups of biochars, especially in low-temperature pyrolysis biochars. The Langmuir isotherm and the pseudo-secondary kinetic model fitted well with the MB adsorption process on biochars. After ball-milled magnetic modification, the adsorption capacity of biochar at 350 °C for MB was increased to 244.6 mg g−1 (8-fold increase), owing to an increase in accessible functional groups. MB removal efficiencies by low-temperature pyrolysis biochars were easily affected by pH, whereas high-temperature pyrolysis biochars could effectively remove MB in a wide pH range. WQM1, with the high adsorption capacity and stability, provided the potential to serve as an adsorbent for MB removal. Based on DFT calculations, the chemisorption and electrostatic interactions were the primary mechanism for enhancing MB removal with ball-milled magnetic biochar at low-temperature pyrolysis, followed by H-bonding, π–π interaction, hydrophobic interaction, and pore filling.
Cow Milk Fatty Acid and Protein Composition in Different Breeds and Regions in China
Authors: Zou Yunxia , Chen Yifei , Meng Qingyong , Wang Yachun , Zhang Yali
Published: October 2024

Cow milk is rich in proteins, fats, carbohydrates, and minerals; however, its precise nutrient content varies based on various factors. In the current study, we evaluated the differences in the fatty acid and protein contents of milk and the factors associated with these differences. To achieve this, samples were collected from seven types of cows in different regions. These included samples from three dairy breeds: Chinese Holstein milk from Beijing, China (BH), Chinese Holstein milk (HH) and Jersey milk (JS) from Hebei province, China; and four dairy/meat breeds: Sanhe milk (SH) from Inner Mongolia Autonomous Region, China, Xinjiang brown milk (XH) and Simmental milk (SI) from Xinjiang Uygur Autonomous Region, China, and Shu Xuanhua milk (SX) from Sichuan province, China. Breed significantly affects total fat, fatty acid, and protein contents. Additionally, geographic region significantly affects the contents of different fatty acids, α-lactalbumin, and lactoferrin. JS has the highest total fat and casein contents. XH samples contain significantly higher unsaturated fatty acid content than BH samples and do not differ significantly from JS. Additionally, the low β-lactoglobulin and high lactoferrin contents in XH samples may be favorable for the growth and development of infants. Our results may inform the development of dairy products from different cow breeds and advance the process of accurate breed identification.
Beware of N-Benzoyloxybenzamides
Authors: Cubitt Jonathan , Davies Mari , Riseley Ross , Evans Gabrielle , Gardiner Sian E. , Kariuki Benson M. , Ward Simon E. , Lloyd-Evans Emyr , Waller-Evans Helen , Jones D. Heulyn
Published: October 2024

Following a High-Throughput Screening campaign to discover inhibitors of acid ceramidase, we report the novel and extremely potent covalent inhibitor, 1. Following resynthesis and stability monitoring, we discovered that 1 is chemically unstable and reacts with DMSO at room temperature. This mode of decomposition is likely general for this class of compound, and we urge caution for their use in drug discovery research.
Influence of Solvent Polarity on Crocin Content and Surface Properties of Saffron (Crocus sativus L.) Extracts
Authors: Rocchi Rachele , Di Mattia Carla , Gabriele Gaia , Neri Lilia , Pittia Paola
Published: October 2024

The saffron composition is being widely studied for authenticity and traceability, but very few works have been carried out to investigate the relationship between the chemical and physico-chemical properties of saffron solutes and their technological functionality in colloidal systems. This study aims at evaluating the surface properties of saffron extracts obtained using solvents of different polarities to achieve extracts with different compositions in terms of the pattern and content of polar and medium polarity crocins. The air–water surface was evaluated alone and in the presence of Tween 20 at different surfactant–extract ratios. Saffron extracts were able to decrease the surface tension of the aqueous phase, indicating the presence of surface-active compounds. In the mixed saffron extract–Tween 20 systems, competitive adsorption at the air–water interface occurred when the surfactant was present at a low concentration, while at concentrations higher than the CMC, Tween 20 hindered the adsorption of the extract surface-active compounds. The results highlight the interesting technological functionality of saffron extracts for applications in colloidal systems. To better exploit their use in the design and development of formulated foods, nutraceutics and pharma products, further studies are needed to unravel the relationship between the composition of saffron extracts and corresponding surface activity.
Phytoecdysteroids: Quantification in Selected Plant Species and Evaluation of Some Effects on Gastric Smooth Muscles
Authors: Todorova Velislava , Ivanova Stanislava , Yotov Viktor , Zaytseva Ekaterina , Ardasheva Raina , Turiyski Valentin , Prissadova Natalia , Ivanov Kalin
Published: October 2024

Phytoecdysteroids (PEs) are naturally occurring steroid compounds, that have recently gained significant attention, due to their diverse biological activities and high therapeutic potential. The aim of the present study was to quantify some PEs including 20-hydroxyecdysterone (20-HE), ponasterone A (PA), and turkesterone (TU) in selected plant foods and Rhaponticum carthamoides extract. Furthermore, the effects of 20-HE, TU, and R. carthamoides extract, were investigated with in vitro methods using isolated smooth muscle tissues. The levels of 20-HE in the analyzed samples exhibited significant differences, with kaniwa seed extract containing the highest amount, followed by spinach leaf extract, quinoa seed extract, and asparagus stem extract. The in vitro analyses suggested that R. carthamoides extract exhibits dose-dependent cytotoxic effects on smooth muscle cells, with low doses promoting contraction and higher doses inducing relaxation. Additionally, the extract demonstrated a significant inhibitory effect on ACh-induced contractions, while 20-HE enhanced the contractile response. The current findings highlighted phytoecdysteroids’ potential for modifying gastrointestinal motility.
In Situ Synthesis of CoMoO4 Microsphere@rGO as a Matrix for High-Performance Li-S Batteries at Room and Low Temperatures
Authors: Zhang Ronggang , Xiong Haiji , Liang Jia , Yan Jinwei , Deng Dingrong , Li Yi , Wu Qihui
Published: October 2024

Lithium–sulfur batteries (Li-S batteries) have attracted wide attention due to their high theoretical energy density and the low cost of sulfur cathode material. However, the poor conductivity of the sulfur cathode, the polysulfide shuttle effect, and the slow redox kinetics severely affect their cycling performance and Coulombic efficiencies, especially under low-temperature conditions, where these effects are more exacerbated. To address these issues, this study designs and synthesizes a microspherical cobalt molybdate@reduced graphene oxide (CoMoO4@rGO) composite material as the cathode material for Li-S batteries. By growing CoMoO4 nanoparticles on the rGO surface, the composite material not only provides a good conductive network but also significantly enhances the adsorption capacity to polysulfides, effectively suppressing the shuttle effect. After 100 cycles at room temperature with a current density of 1 C, the reversible specific capacity of the battery stabilizes at 805 mAh g−1. Notably, at −20 °C, the S/CoMoO4@rGO composite achieves a reversible specific capacity of 840 mAh g−1. This study demonstrates that the CoMoO4@rGO composite has significant advantages in suppressing polysulfide diffusion and expanding the working temperature range of Li-S batteries, showing great potential for applications in next-generation high-performance Li-S batteries.