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The cardiovascular protective effect and mechanism of calycosin and its derivatives

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Chinese Journal of Natural Medicines 2020年第12期18卷 907-915页

作者： PAN Li zhang xuan-Fen WEI Wan-Sheng zhang Jing LI zhen-zhen Department of Cardiopulmonary Bypass Lanzhou University Second HospitalLanzhou 730000China Department of Orthopaedic Surgery Lanzhou University Second HospitalLanzhou 730000China

Cardiovascular disease is the main cause of mortality and morbidity in the world,especially in developing countries.Drug therapy is one of the main ways to treat cardiovascular diseases.Among them,great progress has been made in the treatment of cardiovascular diseases with traditional Chinese medicine.In terms of experimental research,the mechanism of traditional Chinese medicine in the treatment of cardiovascular diseases has been thoroughly discussed in vitro and in vivo.In terms of clinical treatment,traditional Chinese medicine with flavonoids,saponins and alkaloids as the main effective components has a definite effect on the treatment of cardiovascular diseases such as arrhythmia,myocardial ischemia,angina pectoris and myocardial infarction,with high safety and good application prospects.With the further research on the effective ingredients,mechanism and adverse reactions of traditional Chinese medicine,it will be beneficial to the effectiveness of traditional Chinese medicine,reduce side effects and promote the modernization of traditional Chinese medicine.Calycosin and its derivatives,the main bioactive flavonoids in Astragalus membranaceus have multiple biological effects,such as antioxidant,pro-angiogenesis,anti-tumour,and anti-inflammatory effects.Based on the above biological effects,calycosin has been shown to have good potential for cardiovascular protection.The potent antioxidant effect of calycosin may play an important role in the cardiovascular protective potential.For injured cardiac myocytes,calycosin and its derivatives can alleviate the cell damage mainly marked by the release of myocardial enzymes and reduce the death level of cardiac myocytes mainly characterized by apoptosis through various mechanisms.For vascular endothelial cells,calycosin also has multiple effects and multiple mechanisms,such as promoting vascular endothelial cell proliferation,exerting vasodilating effect and directly affecting the synthesis function of endothelial cells.The present review will address the bioactivi

关键词： Cardiovascular disease Calycosin Cadiac myocytes Vascular endothelial cells Protective effect

Ultrasonic vibration-assisted multi-scale plastic forming of high-entropy alloys in milliseconds

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Rare Metals 2023年第4期42卷 1146-1153页

作者： Wen-Xin Wen Lu-Yao Li zhen Li Wen-Qing Ruan Shuai Ren Zhen-Xuan Zhang Xiong Liang Huan Liu Jiang Ma Shenzhen Key Laboratory of High Performance Nontraditional Manufacturing College of Mechatronics and Control EngineeringShenzhen UniversityShenzhen518060China Department of Mechanics and Aerospace Engineering Southern University of Science and TechnologyShenzhen518055China College of Mechanics and Materials Hohai UniversityNanjing210000China

Due to their excellent properties of specific strength,fracture resistance,corrosion and oxidation resistance,the high-entropy alloys have attracted widespread attention as engineering materials.For the sake of industrial applications,one of the essential stages would be the forming of them,especially the construction of multi-sc ale structures from macroscale to nanoscale.

关键词： alloys materials. resistance

Synthesis of Helical Poly(phenylacetylene)s Carrying Dendritic Pendants with Varied Branching Densities Through Polymerization in Different Solvents

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高分子科学:英文版 2023年第10期41卷 1543-1554页

作者： zhen-zhen Sun Yan-Ning zhang Hao-Yu Qiu Xue-Ting Lu Liang-xuan Ren Le-Fei Shen Wen Li Afang zhang International Joint Laboratory of Biomimetic and Smart Polymers School of Materials Science and EngineeringShanghai UniversityShanghai200444China

Helical poly(phenylacetylene)s(PPAs)have received extensive attention because of their features in dynamic chirality and promising applications.Therefore,understanding relationship among the polymer molecular structures,polymerization conditions and tunability of their chirality is of key scientific value.Recently,we developed a novel class of dendronized PPAs carrying 3-fold dendritic oligo(ethylene glycols)(OEGs)via alanine linkage,and found that these bulky polymers exhibited tunable helical conformations through thermally-mediated dehydration and aggregation.Herein,we report on synthesis of a homologous series of dendronized PPAs that carry 2-fold,3-fold or 6-fold dendritic OEG pendants,and focus on effects of molecular topological structures,peripheral units and polymerization solvents on the thermoresponsiveness and their conformation switching behaviors.Effects of branching density and peripheral units(ethoxyl or methoxyl)of the dendritic OEG pendants were examined,and found to play a decisive role on the helical conformation and thermoresponsiveness of these dendronized PPAs due to their different bulkiness and overall hydrophilicity.In addition,different polymerization solvents were checked for their possible influence on the polymerization,thermoresponsive behavior and the chirality of the resulting polymers.For polymerization in selective solvents like water or methanol,the obtained dendronized PPAs exhibited weak thermal transitions,while polymerization in non-selective solvent like THF furnished PPAs with characteristic thermoresponsive behavior,indicating that solvents were involved in the process of polymerization of the dendronized macromonomers.More interestingly,different chiralities of the PPAs through polymerization in various solvents were retained,irrelevant to the purification process and solvents treatments.This work suggests that the topological structures together with polymerization solvents can modulate the thermoresponsive behavior and helical conformation of the dendronized PPAs.

关键词： Helical polymer Dendronized polymer Thermores ponsive polymer Solvation Dendritic oligoethylene glycol

Simultaneous prestack inversion of variable-depth streamer seismic data

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Applied Geophysics 2019年第1期16卷 92-100页

作者： zhang zhen-Bo xuan Yi-Hua Deng Yong CNOOC China Limited Shenzhen BranchShenzhen 518000China

Variable-depth streamer seismic data are characterized by low and high frequencies and can be used to obtain high-quality and resolution images of complex subsurface structures. Taking advantage of the frequency range in the variable-depth streamer data, we propose the simultaneous inversion of prestack data from variable-offset stack gathers to obtain the P-wave impedance, S-wave impedance, and density. Next, we validate the method by using model and actual variable-depth streamer data from the Huizhou block. The results suggest that the broadband data recorded by variable-depth streamers improve the signal-to-noise ratio and quality of the inversion results and outperform the constant-depth streamer data in delineating the underground stratigraphy.

关键词： streamer prestack variable inversion reservoir frequency

Accurate atomic scanning transmission electron microscopy analysis enabled by deep learning

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Nano Research 2024年第4期17卷 2971-2980页

作者： Tianshu Chu Lei Zhou Bowei zhang Fu-zhen xuan Shanghai Key Laboratory of Intelligent Sensing and Detection Technology East China University of Science and TechnologyShanghai 200237China School of Mechanical and Power Engineering East China University of Science and TechnologyShanghai 200237China Key Laboratory of Pressure Systems and Safety of Ministry of Education East China University of Science and TechnologyShanghai 200237China

Currently,the machine learning(ML)-based scanning transmission electron microscopy(STEM)analysis is limited in the simulative stage,its application in experimental STEM is needed but challenging.Herein,we built up a universal model to analyze the vacancy defects and single atoms accurately and rapidly in experimental STEM images using a full convolution network.In our model,the unavoidable interference factors of noise,aberration,and carbon contamination were fully considered during the training,which were difficult to be considered in the past.Even toward the simultaneous identification of various vacancy types and low-contrast single atoms in the low-quality STEM images,our model showed rapid process speed(45 images per second)and high accuracy(>95%).This work represents an improvement in experimental STEM image analysis by ML.

关键词： deep learning low-dimensional materials atomic defects single atoms

Data-driven rational design of single-atom materials for hydrogen evolution and sensing

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Nano Research 2024年第4期17卷 3352-3358页

作者： Lei Zhou Pengfei Tian Bowei zhang Fu-zhen xuan Shanghai Key Laboratory of Intelligent Sensing and Detection Technology East China University of Science and TechnologyShanghai 200237China School of Mechanical and Power Engineering East China University of Science and TechnologyShanghai 200237China Key Laboratory of Pressure Systems and Safety of Ministry of Education East China University of Science and TechnologyShanghai 200237China

Herein we proposed a data-driven high-throughput principle to screen high-performance single-atom materials for hydrogen evolution reaction(HER)and hydrogen sensing by combing the theoretical computations and a topology-based multi-scale convolution kernel machine learning algorithm.After the rational training by 25 groups of data and prediction of all 168 groups of single-atom materials for HER and sensing,respectively,a high prediction accuracy(>0.931 R^(2) score)was achieved by our model.Results show that the promising HER catalysts include Pt atoms in C_(4) and Sc atoms in C_(1)N_(3) coordination environment.Moreover,Y atoms in C_(4) coordination environment and Cd atoms in C_(2)N_(2)-ortho coordination environment were predicted with great potential as hydrogen sensing materials.This method provides a way to accelerate the discovery of innovative materials by avoiding the time-consuming empirical principles in experiments.

关键词： machine learning single-atom materials sensing hydrogen evolution

A Comparative Study Between Tumor Blood Vessels and Dynamic Contrast-enhanced MRI for Identifying Isocitrate Dehydrogenase Gene 1(IDH1)Mutation Status in Glioma

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Current Medical Science 2022年第3期42卷 650-657页

作者： Shi-hui LI Nan-xi SHEN Di WU Ju zhang Jia-xuan zhang Jing-jing JIANG Wen-zhen ZHU Department of Radiology Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430030China

Objective Isocitrate dehydrogenase gene(IDH)mutations are associated with tumor angiogenesis and therefore play an important role in glioma management.This study compared the performance of tumor blood vessels counted from contrast-enhanced 3D brain volume(3D-BRAVO)sequence and dynamic contrast-enhanced(DCE)MRI in differentiating IDH1 status in gliomas.Methods Forty-four glioma patients[16 with IDH1 mutant-type(IDH1-MT),28 with IDH1 wild-type(IDH1-WT)]were retrospectively analyzed.A blood vessel entering a tumor was defined as an intratumoral vessel;a blood vessel adjacent to the edge of a tumor was defined as a peritumoral vessel.Combined vessels were defined as the sum of the intratumoral and peritumoral vessels.DCE-derived metrics of tumor were normalized to the contralateral normal-appearing white matter.Results Intratumoral,peritumoral,and combined tumor blood vessels were all significantly different between IDH1-MT and IDH1-WT gliomas,and the range of area under curves(AUCs)was 0.816–0.855.For DCE-derived parameters,cerebral blood volume,cerebral blood flow,mean transit time,and volume transfer constant were significantly different between IDH1-MT and IDH1-WT gliomas,and the range of AUCs was 0.703–0.756.Combined vessels possessed the best performance for identifying IDH1 mutations in gliomas(AUC:0.855,sensitivity:0.857,specificity:0.812,P<0.001).Conclusion The number of tumor blood vessels has comparable diagnostic performance with DCE-derived parameters for differentiating IDH1 mutations and can serve as a potential imaging biomarker to reflect IDH1 mutations in gliomas.

关键词： dynamic contrast-enhanced perfusion glioma isocitrate dehydrogenase gene tumor blood vessel

Research on manufacture technology of spherical fuel elements by dry-bag isostatic pressing

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Nuclear Science and Techniques 2022年第10期33卷 79-89页

作者： zhen-Ming Lu Wen-Ke zhang Jie zhang Xiang-Wen Zhou Kai-Hong zhang Ma-Lin Liu xuan-Ke Li Bing Liu Hubei Province Key Laboratory of Coal Conversion and New Carbon Materials Wuhan University of Science and TechnologyWuhan 430081China Institute of Nuclear and New Energy Technology Collaborative Innovation Center of Advanced Nuclear Energy TechnologyTsinghua UniversityBeijing 100084China

The steady development of high-temperature gas-cooled reactors(HTRs) has increased the requirements for the production cost and quality of fuel elements. Green fuel element pressing is one of the key steps to increase the production capacity. This paper proposes a proprietary vacuum dry-bag isostatic pressing(DIP) apparatus. The structural change of the matrix graphite powder during the DIP process was examined by analyzing the density change of the matrix graphite spheres with pressure. The soft molding process was simulated using the finite element method. The dimensional changes in the spheres during the pressing, carbonization, and purification stages were explored. The performance of the fuel matrix produced by the DIP method was comprehensively examined. The fuel matrix met the technical requirements and its anisotropy was significantly reduced. The DIP method can significantly improve both the production efficiency and quality of fuel elements. This will play a key role in meeting the huge demand for fuel elements of HTRs and molten salt reactors.

关键词： Dry-bag isostatic pressing High-temperature gas-cooled reactor(HTR) Spherical fuel element Finite element simulation Soft molding

Highly stretchable,conductive,and wide-operating temperature ionogel based wearable triboelectric nanogenerator

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Nano Research 2023年第9期16卷 11638-11645页

作者： Qianqian Zhu Weiqiang Liao Cong Sun xuan Qin Fangjia zhang Haifeng Ji Yuqi Li zhen Wen Xuhui Sun Institute of Functional Nano and Soft Materials(FUNSOM) Jiangsu Key Laboratory for Carbon-Based Functional Materials and DevicesSoochow UniversitySuzhou 215123China Key Laboratory of New Processing Technology for Nonferrous Metals and Materials Ministry of EducationCollege of Materials Science and EngineeringGuilin University of TechnologyGuilin 541004China

The rapid development of wearable electronic products brings challenges to corresponding power supplies.In this work,a thermally stable and stretchable ionogel-based triboelectric nanogenerator(SI-TENG)for biomechanical energy collection is proposed.The ionic conductivity of the ionogel increased to 0.53 S·m^(−1) through optimal regulation of the amount of aminoterminated hyperbranched polyamide(NH2-HBP),which also has high strain of 812%,excellent stretch recovery,and wide operating temperature range of−80 to 250°C.The SI-TENG with this ionogel as electrode and silicone rubber both as the triboelectric layer and encapsulation layer exhibits high temperature stability,stretchability,and washability.By adding appropriate amount of nano SiO2 to triboelectric layer,the output performance is further improved by 93%.Operating in singleelectrode mode at 1.5 Hz,the outputs of a SI-TENG with an area of 3 cm×3 cm are 247 V,11.7μA,78 nC,and 3.2 W·m^(−2),respectively.It was used as a self-charging power supply to charge a 22μF capacitor to 1.6 V in 167 s with the palm patting and then to power the electronic calculator.Furthermore,the SI-TENG can also be used as a self-powered motion sensor to detect the amplitude and frequency of finger bending,human swallowing,nodding,and shaking of the head motion changes through the analysis of the output voltage.

关键词： triboelectric nanogenerator ionogel self-powered motion sensor stretchable temperature stability