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Food Science and Human Wellness 2024年第2期13卷 909-919页

作者： Xiangxin Li Yijing Pu Bangdi Liu Xiaoming Fang Wenjun Peng Weibo Jiang Wenli Tian Institute of Apicultural research Chinese Academy of Agricultural SciencesBeijing 100093China College of Food Science and Nutritional Engineering China Agricultural UniversityBeijing 100083China Academy of Agricultural Planning and Engineering Ministry of Agriculture and Rural AffairsBeijing 100125China

Free cholesterol has been considered to be a critical risk factor of nonalcoholic fatty liver disease(NAFLD).It remains unknown whether dietary intake of condensed tannins(CTs)have distinguishable effects to alleviate liver damage caused by a high cholesterol *** C57BL/6 mice were fed a high cholesterol diet for 6 weeks,and given CTs treatment at a dosage of 200 mg/(kg·day)at the same *** results indicated that compared with mice fed a normal diet,a high cholesterol diet group resulted in significant weight loss,dysregulation of lipid metabolism in blood and liver,and oxidative stress in the liver,but CTs treatment dramatically reversed these negative *** and eosin(H&E)staining and frozen section observation manifested that CTs treatment could effectively reduce the deposition of liver cholesterol and tissue necrosis caused by high cholesterol *** alleviated liver injury mainly by regulating the expression of related genes in cholesterol metabolism pathway and AMPK *** results confirmed that CTs have remarkable cholesterol lowering and anti-liver injury effects in vivo.

关键词： Condensed tannins High cholesterol Liver injury Antioxidants Transcriptomic analysis

Inhibitory effect of procyanidin B2 and tannin acid on cholesterol esterase and their synergistic effect with orlistat

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Food Science and Human Wellness 2024年第1期13卷 360-369页

作者： Xiangxin Li Yijing Pu Haitao Jiang Wenxiao Jiao Wenjun Peng Wenli Tian Weibo Jiang Xiaoming Fang Institute of Apicultural research Chinese Academy of Agricultural SciencesBeijing 100093China College of Food Science and Nutritional Engineering China Agricultural UniversityBeijing 100083China College of Food Science and Engineering Qilu University of Technology(Shandong Academy of Sciences)Jinan 250353China

This study was aimed to analyze the effect of procyanidin B2(PC)and tannin acid(TA)on the activities of cholesterol esterase(CEase)and the inhibitory mechanisms of enzymatic *** interaction mechanisms were investigated by enzymatic kinetics,multi-spectroscopy methods,thermodynamics analysis,molecular docking,and dynamic *** and TA could bind with CEase and inhibit the activity of enzyme in a mixed-competitive manner and non-competitive manner,which was verified by molecular docking simulations and dynamics ***,PC and TA showed the synergistic inhibition with ***,UVvis and the thermodynamic analysis revealed that the complexes were formed from CEase and inhibitors by noncovalent *** revealed by the circular dichroism results,both PC and TA decreased enzymatic activities by altering the conformations of *** inhibition of PC and TA on CEase might be one mechanism for its cholesterol-lowering effect.

关键词： Cholesterol esterase Polyphenols Interaction mechanisms Molecular dynamic simulation Synergistic effect

Soil bacterial and fungal communities resilience to long-term nitrogen addition in subtropical forests in china

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Journal of Forestry research 2024年第2期35卷 95-108页

作者： Xinlei Fu Yunze Dai Jun Cui Pengfei Deng Wei Fan Xiaoniu Xu School of Forestry and Landscape Architecture Anhui Agricultural UniversityHefei 230036AnhuiPeople’s Republic of China Suzhou Polytechnic Institute of Agriculture Suzhou 215008JiangsuPeople’s Republic of China College of Life and Environment Sciences Huangshan UniversityHuangshan 245041AnhuiPeople’s Republic of China

Atmospheric nitrogen(N)deposition is predicted to increase,especially in the ***,the responses of soil microorganisms to long-term N addition at the molecular level in N-rich subtropical forests have not been clarified.A long-term nutrient addition experiment was conducted in a subtropical evergreen old-growth forest in *** four treatments were:control,low N(50 kg N ha^(-1)a^(-1)),high N(100 kg N ha^(-1)a^(-1)),and combined N and phosphorus(P)(100 kg N ha^(-1)a^(-1)+50 kg P ha^(-1)a^(-1)).Metagenomic sequencing characterized diversity and composition of soil microbial communities and used to construct bacterial/fungal co-occurrence ***-treated soils were more acidic and had higher levels of dissolved organic carbon than *** were no significant differences in microbial diversity and community composition across *** addition of nutrients increased the abundance of copiotrophic bacteria and potentially beneficial microorganisms(e.g.,Gemmatimonadetes,Chaetomium,and Aureobasidium).Low N addition increased microbiome network *** rare fungi were identified as module hubs under nutrient addition,indicating that low abundance fungi were more sensitive to increased *** results indicate that the overall composition of microbial communities was stable but not static to long-term N *** findings provide new insights that can aid predictions of the response of soil microbial communities to long-term N addition.

关键词： Long-term nitrogen addition Old-growth subtropical forest Metagenomics Beneficial microorganisms Co-occurrence network

Multi-Objective Optimization of the Ultrasonic Scalpel Rod and Tip with Improved Performance:Vibration Frequency,Amplitude,and Service Life

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Chinese Journal of Mechanical Engineering 2024年第4期37卷 107-119页

作者： Jiaqi Zhao Yuhao Zhai Xuzhe Jia Naiwen Deng Kunxu Li Guangchao Han Rong Chen Dong Wang Wei Bai School of Mechanical Engineering and Electronic Information China University of GeosciencesWuhan 430074China Shenzhen research Institute China University of GeosciencesShenzhen 518057China College of Engineering Mathematics and Physical SciencesUniversity of ExeterExeter EX44QFUK Shenzhen Huazhong University of Science and Technology research Institute Shenzhen 518000China

Ultrasonic scalpel design for minimally invasive surgical procedures is mainly focused on optimizing cutting ***,an important issue is the low fatigue life of traditional ultrasonic scalpels,which affects their long-term reliability and effectiveness and creates hidden dangers for *** this study,a multi-objective optimal design for the cutting performance and fatigue life of ultrasonic scalpels was proposed using finite element analysis and fatigue *** optimal design parameters of resonance frequency and amplitude were *** setting the transition fillet and keeping the gain structure away from the node position to enable the scalpel to have a high service life with excellent cutting *** frequency modulation method of setting the vibration node bosses at the node position and setting the vibration antinode grooves at the antinode position was ***,the mechanism of the influence of various design elements,such as tip,shank,node position,and antinode position,on the resonance frequency,amplitude,and fatigue life of the ultrasonic scalpel was analyzed,and the optimal design principles of the ultrasonic scalpel were *** proposed ultrasonic scalpel design was confirmed by simulations,impedance measurements,and liver tissue cutting experiments,demonstrating its feasibility and enhanced *** research introduces innovative design strategies to improve the fatigue life and performance of ultrasonic scalpels to address an important issue in minimally invasive surgery.

关键词： Multi-objective optimal design Minimally invasive surgical procedures Service life Ultrasonic scalpel

Identifying the best common factor model via exploratory eactor analysis

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Applied Mathematics(A Journal of Chinese Universities) 2024年第1期39卷 24-33页

作者： HE Bao-hua TANG Rui TAGN Qi-yi School of Big Data Fuzhou University of International Studies and TradeFuzhou 350202China School of Mathematics Sun Yat-Sen UniversityGuangzhou 510275China Department of Computer Science University of BathUK Institute of Insect Science Zhejiang UniversityHangzhou 310058China.

Currently,there is no solid criterion for judging the quality of the estimators in factor *** paper presents a new evaluation method for exploratory factor analysis that pinpoints an appropriate number of factors along with the best method for factor *** proposed technique consists of two steps:testing the normality of the residuals from the fitted model via the Shapiro-Wilk test and using an empirical quantified index to judge the quality of the factor *** are presented to demonstrate how the method is implemented and to verify its effectiveness.

关键词： factor analysis Shapiro-Wilk normality residuals

Acoustic characterization of hydrate formation and decomposition in clay-bearing sediments

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Petroleum Science 2024年第4期21卷 2830-2838页

作者： Yi-Jian Zhu Xiao-Mei Yang Xing Huang Hao Li Xiao-Hui Wang Yi-Fei Sun Peng Xiao Chang-Yu Sun Guang-Jin Chen State Key Laboratory of Heavy Oil Processing College of Chemical Engineering and Environment China University of Petroleum

Understanding the acoustic characteristics of hydrates in various sediments is crucial for hydrate resource detection and safe and efficient exploitation, as hydrate occurrence patterns vary greatly in different sediments. In this work, sediments with different bentonite contents, water saturations, and types were prepared to investigate the characteristics of P-wave velocity(reflecting the magnitude of hydrate saturation in the sediment) and amplitude(reflecting the degree of hydrate-sediment cementation) during hydrate formation and depressurization. During hydrate formation, the P-wave velocity and amplitude have similar trends. As clay content increases, the P-wave velocity increase rates quickened. On the other hand, the increased rate of P-wave velocity slows down with the increase of water saturation in the clay-bearing sediments. Comparing various types of sediment shows that the water absorption and swelling of bentonite reduce the pore space, speeding up the cementation of the hydrate with the sediment and increasing P-wave velocity at a faster rate. Correspondence between P-wave velocity and hydrate saturation is strongly related to sediment type, clay content, and water *** rapidly decreasing amplitude in the early stage of hydrate depressurization indicates that hydrate in clay-bearing sediments is weakly cemented to the sediments, which is prone to stratigraphic *** findings of this study offer guidance for hydrate resource assessments in clay-bearing sediments as well as geologic risk estimations during hydrate mining.

关键词： Gas hydrate Bentonite Illite P-wave velocity Amplitude

Topologically engineering of π-conjugated macrocycles: Tunable emission and photochemical reaction toward multi-cyclic polymers

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Chinese Chemical Letters 2024年第10期35卷 233-240页

作者： Yi Liu Peng Lei Yang Feng Shiwei Fu Xiaoqing Liu Siqi Zhang Bin Tu Chen Chen Yifan Li Lei Wang Qing-Dao Zeng Shenzhen Key Laboratory of Polymer Science and Technology Guangdong Research Center for Interfacial Engineering of Functional MaterialsCollege of Materials Science and EngineeringShenzhen UniversityShenzhen 518060China CAS Key Laboratory of Standardization and Measurement for Nanotechnology CAS Center for Excellence in NanoscienceNational Center for Nanoscience andTechnology(NCNST)Beijing100190China Institute of Critical Materials for Integrated Circuits Shenzhen Polytechnic UniversityShenzhen 518055China

The topology of conjugated macrocycles had significant impacts on their photo-physical and photochemical ***,a series ofπ-conjugated macrocycles with diverse topology were synthesized via intramolecular McMurry *** chemical structure and macrocyclic topology were unambiguously confirmed via NMR,MALDI-TOF mass spectra,crystal analysis and scanning tunneling microscopy(STM).Depending on the structural topology and structural rigidity,these cyclic compounds display obviously distinctive emission behavior and photochemical reactions in the solution and in the solid *** phenylene vinylene macrocycle(denoted as MST)exhibiting aggregation-induced emission behavior,was more vulnerable to photo-cyclization in solution and triplet sensitizer promoted photodimerization due to lower strain and more flourishing intramolecular *** UV light irradiation,relatively more flexible MST could yield the anti-dimer via triplet excimer on the HOPG surface confirmed by STM *** contrast,highly constrained bicyclic analogue(named as DMTPE)with central tetraphenylethene core,displayed high emission quantum yields of 68%both in solution and in the solid state,and was relatively inert to photochemical reactions and yield syn-dimer on the surface via singlet excimer involved[2+2]*** on the solution-mediated photo-polymerization of MST moiety,multicyclic porous carbon-rich ribbon connected with four-membered ring was successfully constructed and validated via STM imaging.

关键词： Conjugated macrocycle Scanning tunneling microscopy Aggregation-induced emission Photochemistry Multicyclicribbon

Long-Chain Alkenones in the South Yellow Sea Sediments and Their Indicative Significance for Haptophytes Species

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Journal of Ocean University of china 2024年第5期23卷 1287-1296页

作者： XU Yakun YANG Xinxin XIAO Rui XING Lei Key Laboratory of Marine Chemistry Theory and Engineering Technology Ministry of EducationOcean University of ChinaQingdao 266100China Laboratory of Marine Ecology and Environment Science Qingdao National Laboratory for Marine Science and TechnologyQingdao 266071China

Long-chain alkenones(LCAs)have been widely used as important biomarkers in palaeoceanographic ***,the commonly used LCAs proxies are mainly based on C_(37) alkenones,and it is still lack of the studies about the distribution and in-dications of LCAs with different chain lengths other than C_(37) ***,the composition and distribution of LCAs were ana-lyzed in surface sediments from the southern Yellow Sea(SYS)and a sedimentary core(A02-C)from the central Yellow Sea(YS)mud *** results showed that C_(37),C_(38) and C_(39) alkenones were the major LCAs in surface sediments of the SYS,and the relative contents of C_(38:2)Et,C_(37:2)Me,C_(37:3)Me,C_(38:2)Me,C_(38:3)Et,C_(38:3)Me,C_(39:2)Et and C_(39:3)Et were 18.3%-59.8%,22.6%-41.2%,7.4%-23.0%,6.6%-15.4%,3.8%-13.3%,3.6%-8.7%,2.8%-6.0% and 0.7%-3.0%,*** the relationships of U_(38Me)^(K)-U_(38Et)^(K) and U_(37)^(K')-U_(38Et)^(K) indicate that LCAs are mainly derived from Emiliania huxleyi(***).High ratios of total C_(37) alkenones to total C_(38) alkenones(K_(37)/K_(38))(1-1.2)were found in the central SYS,corresponding to the relatively high abundance of ***;while low ratios of K_(37)/K_(38)(0.7-0.9)were observed at nearshore area of the SYS where Gephyrocapsa oceanica(***)has rela-tively high *** spatial distribution of K_(37)/K_(38) ratio is also consistent with that of coccolithophores nannofossil in the *** addition,K_(37)/K_(38) ratio in core A02-C varied from 0.7 to 1.1 with a gradual decreasing trend during the past 5.5 *** suggests that the relative abundance of *** decreased gradually,caused by the changes in the Yellow Sea Warm Current(YSWC)and the East Asian Winter Monsoon(EAWM)during this period.

关键词： alkenones southern Yellow Sea sediment Yellow Sea Warm Current

Elemental Compositions of Clinopyroxenes from Southern Okinawa Trough Basalt:Implications for Magmatism and Structural Environment in an Initial Back-Arc Basin

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Journal of Ocean University of china 2024年第3期23卷 643-653页

作者： GUO Kun ZHAI Shikui FAN Di ZHANG Xia ZHANG Yu ZHU Zhimin Laoshan Laboratory Qingdao 266237China Key Laboratory of Submarine Geosciences and Prospecting Techniques Ministry of EducationCollege of Marine GeosciencesOcean University of ChinaQingdao 266100China Key Laboratory of Submarine Geosciences&Second Institute of Oceanography Ministry of Natural ResourcesHangzhou 310012China

The major and trace elemental compositions of clinopyroxene from basalt were used to characterize the nature of the primitive magma and structural environment beneath the southern Okinawa Trough(SOT),which is an initial back-arc basin at a continental *** clinopyroxenes in the basalt were augite with variable Mg^(#)contents(73.37-78.22).The regular variations in major oxide contents(i.e.,CaO,FeO,TiO_(2),and Cr)with decreasing Mg#implied that the clinopyroxenes evolved from being enriched in Mg,Ca,and Cr to being enriched in Fe and *** clinopyroxenes had relatively low rare earth element concentrations(7.51×10^(-6) to 12.68×10^(-6))and negative Eu anomalies(δEu=0.67-0.95).The Kd_(cpx) values of clinopyroxenes(0.2-0.26),which were used to examine whether the clinopyroxene was equilibrated with its host basalt,demonstrate that these clinopyroxene phenocrysts were not captured crystals but were instead produced by crystallization differentiation of the *** calculated clinopyroxene crystallization temperatures showed a narrow range of 990-1061℃,and their crystallization pressures ranged from 2.0 to 3.2 *** geochemistry features of these clinopyroxenes indicated that the parent magma belonged to the subalkaline tholeiitic magma series and suggested that the magma experienced crystallization differentiation of olivine,plagioclase,and clinopyroxene,where the crystallization of plagioclase occurred earlier than that of *** with geophysical data,this research on primitive magma and its crystallization differentiation from clinopyroxene indicates that the SOT is in the stage of‘seafloor spreading’and that basaltic rocks produced from tholeiitic magma represent the generation of oceanic crust.

关键词： trace elements clinopyroxenes southern Okinawa Trough seafloor spreading back-arc basin

Machine Learning-Based research on Tensile Strength of SiC-Reinforced Magnesium Matrix Composites via Stir Casting

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Acta Metallurgica Sinica(English Letters) 2024年第3期37卷 453-466页

作者： Zhihong Zhu Wenhang Ning Xuanyang Niu Yuhong Zhao Beijing Advanced Innovation Center for Materials Genome Engineering University of Science and Technology BeijingBeijing 100083China School of Materials Science and Engineering Collaborative Innovation Center of Ministry of Education and Shanxi Province for High-Performance Al/Mg Alloy MaterialsNorth University of ChinaTaiyuan 030051China Institute of Materials Intelligent Technology Liaoning Academy of MaterialsShenyang 110004China

SiC is the most common reinforcement in magnesium matrix composites,and the tensile strength of SiC-reinforced magnesium matrix composites is closely related to the distribution of *** a uniform distribution of SiC requires fine control over the parameters of SiC and the processing and preparation ***,due to the numerous adjustable parameters,using traditional experimental methods requires a considerable amount of experimentation to obtain a uniformly distributed composite ***,this study adopts a machine learning approach to explore the tensile strength of SiC-reinforced magnesium matrix composites in the mechanical stirring casting *** analyzing the influence of SiC parameters and processing parameters on composite material performance,we have established an effective predictive ***,six different machine learning regression models have been developed to predict the tensile strength of SiC-reinforced magnesium matrix *** validation and comparison,our models demonstrate good accuracy and reliability in predicting the tensile strength of the composite *** research findings indicate that hot extrusion treatment,SiC content,and stirring time have a significant impact on the tensile strength.

关键词： Machine learning Stirring casting Magnesium matrix composite Tensile strength