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Mesenchymal stem cell-derived small extracellular vesicles mitigate oxidative stress-induced senescence in endothelial cells via regulation of miR-146a/Src

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Signal Transduction and Targeted Therapy 2021年第11期6卷 3318-3332页

作者： xian xiao Meiqian Xu Hongliang Yu Liping Wang xiaoxia Li Janusz Rak Shihua Wang Robert Chunhua zhao Institute of Basic Medical Sciences Chinese Academy of Medical Sciences School of Basic Medicine Peking Union Medical CollegeBeijingChina Department of Genetics and Cell Biology Basic medical collegeQingdao University308 Ningxia Road266071QingdaoChina Research Institute of the McGill University Health Centre Glen SiteMcGill UniversityMontrealQCH4A 3J1Canada Department of Cell Biology School of Life SciencesShanghai University200444ShanghaiChina

Senescent endothelial cells (ECs) could impair the integrity of the blood vessel endothelium, leading to vascular aging and a series of diseases, such as atherosclerosis, diabetes. Preventing or mitigating EC senescence might serve as a promising therapeutic paradigm for these diseases. Recent studies showed that small extracellular vesicles (sEV) have the potential to transfer bioactive molecules into recipient cells and induce phenotypic changes. Since mesenchymal stem cells (MSCs) have long been postulated as an important source cell in regenerative medicine, herein we investigated the role and mechanism of MSC-derived sEV (MSC-sEV) on EC senescence. In vitro results showed that MSC-sEV reduced senescent biomarkers, decreased senescence-associated secretory phenotype (SASP), rescued angiogenesis, migration and other dysfunctions in senescent EC induced by oxidative stress. In the In vivo natural aging and type-2 diabetes mouse wound-healing models (both of which have senescent ECs), MSC-sEV promoted wound closure and new blood vessel formation. Mechanically, miRNA microarray showed that miR-146a was highly expressed in MSC-sEV and also upregulated in EC after MSC-sEV treatment. miR-146a inhibitors abolished the stimulatory effects of MSC-sEV on senescence. Moreover, we found miR-146a could suppress Src phosphorylation and downstream targets VE-cadherin and Caveolin-1. Collectively, our data indicate that MSC-sEV mitigated endothelial cell senescence and stimulate angiogenesis through miR-146a/Src.

关键词： miR wound healing

Synthesis,Characterization and Non-linear Optical Properties of a New Organic Dye:DEAHAS

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Chinese Chemical Letters 2003年第11期14卷 1203-1206页

作者： Yun Xing YAN xiao Qiang YU Dong WANG xian zhao Qi FANG Min Hua JIANG State Key Laboratory of Crystal Materials Shandong UniversityJi'nan 250100

Trans-4- (N-2-hydroxyethyl-N-ethyl amino)-4ˊ-(diethyl amino)stilbene (DEAHAS) has been synthesized and characterized by 1H NMR, IR and elemental analysis. Linear absorption, single-photon induced fluorescence and two-photon induced fluorescence are experimentally studied. DEAHAS has an effective two-photon absorption cross-sections ofσ2 = 1.19×10-46 cm4·s/photon at 532 nm by using an open aperture Z-scan technique and exhibits a strong two-photon induced blue fluorescence of 430 nm when pumped with 800 nm laser irradiation.

关键词： Synthesis two-photon-induced fluorescence DEAHAS.

A novel route to enhance high-temperature mechanical property and thermal shock resistance of low-carbon Mgo-C bricks by introducing ZrSiO_(4)

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Journal of Iron and Steel Research International 2024年第6期31卷 1436-1448页

作者： Chun-hui Sun Ling-ling Zhu Hao Yan Wei zhao Jing-xuan Liu Lin Ren xian-tang zhao xiao-song Tong Shu-wen Yu Beijing Lirr High-Temperature Materials Co. Ltd.Beijing 102211China School of Materials Science and Engineering Henan Province Industrial Technology Research Institute of Resources and MaterialsZhengzhou UniversityZhengzhou 450001HenanChina School of Chemistry and Chemical Engineering Suzhou UniversitySuzhou 234000AnhuiChina

Conventional MgO-C bricks(graphite content>14 wt.%)produce a great deal of greenhouse gas emission,while low-carbon MgO-C bricks have serious thermal shock resistance during high-temperature *** enhance the high-temperature mechanical property and thermal shock resistance of low-carbon MgO-C bricks,a novel route of introducing ZrSiO_(4) powder into low-carbon MgO-C bricks was reported in such refractories with 2 wt.% flaky *** results indicate that the low-carbon MgO-C brick with 0.5 wt.%ZrSiO_(4) addition has the maximum hot modulus of rupture at 1400℃ and the corresponding specimen fired in the carbon embedded atmosphere has the maximum residual strength ratio(98.6%)after three thermal shock *** is found that some needle-like AlON and plate-like Al_(2)O_(3)-ZrO_(2) composites were in situ formed in the matrices after the low-carbon MgO-C bricks were coked at 1400℃,which can enhance the high-temperature mechanical property and thermal shock resistance due to the effect of fiber toughening and particle ***,CO_(2) emission of the newly developed low-carbon MgO-C bricks is reduced by 58.3% per ton steel after using them as the working lining of a 90 t vacuum oxygen decarburization ladle.

关键词： Low-carbon MgO-C brick ZrsiO_(4) Synergistic toughening effect High-temperature mechanical property Thermal shock resistance Vacuum oxygen decarburization ladle

Reaction characteristics and kinetics of gallium in chlorination roasting of copper tailings using calcium chloride

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Rare Metals 2022年第3期41卷 1063-1070页

作者： Chang Lei Tao Chen Bo Yan xian-Ming xiao State Key Laboratory of Organic Geochemistry Guangzhou Institute of GeochemistryChinese Academy of SciencesGuangzhou 510640China University of Chinese Academy of Sciences Beijing 100082China

The mineral composition of copper tailings was examined, and the phase analysis of gallium was conducted for recovery of the rare scattered metal gallium from copper tailings. The reaction characteristics and kinetics of gallium in the chlorination roasting of copper tailings were investigated in a tube furnace apparatus under different conditions, including roasting temperature, quantity of chlorination agent,roasting time, and airflow. Calcium chloride was chosen for the chlorination reaction because it is highly effective for volatilization of metals. The results show that gallium mainly exists in limonites in the form of oxides, and increases in roasting temperature, quantity of chlorination agent, and roasting time are conducive to increasing the chloridizing volatilization rate of gallium. The tailings gradually melt when the roasting temperature exceeds 900℃, resulting in a decrease in the chloridizing volatilization rate of gallium. The chloridizing volatilization rate of gallium reaches 78.86%at roasting temperature of 900℃ for 40 min, airflow of 0.1 m^(3)·h^(-1), and calcium content of 33.33 wt%. Study of the reaction kinetics of gallium in chlorination roasting shows that the values of activation energy both for chemically controlled anddiffusion-controlled reactionsare44.64and11.93 kJ·mol^(-1), respectively. This indicates that the chemical reaction serves an important function in the chlorination volatilization of gallium. Taken together, the results reveal the usefulness of tailings as a source of rare metals and provide a basis for gallium recovery and environmentally friendly disposal of copper tailings.

关键词： Copper tailings Gallium recovery Chlorination roasting Calcium chloride Kinetics

Effect of multiple parameters on the supersonic gas-jet target characteristics for laser wakefield acceleration

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Nuclear Science and Techniques 2021年第7期32卷 90-98页

作者： Qiu-Shi Liu Ming-Jiang Ma Bao-Zhen zhao xiao-Hua Zhang Chong Lv xiang-Hao Meng Ji Zhang xiao-Na Ban zhao Wang xiao-Feng Xi Bao-xian Tian Chuang-Ye He Bing Guo Department of Nuclear Physics China Institute of Atomic EnergyBeijing 102413China

The supersonic gas-jet target is an important experimental target for laser wakefield acceleration(LWFA),which has great potential for driving novel radiation sources such as betatron radiation and Compton scattering gamma *** to different electron acceleration requirements,it is necessary to provide specific supersonic gas jets with different density profiles to generate electron beams with high quality and high repetition *** this study,the interference images and density profiles of different gas-jet targets were obtained through a modified Nomarski interference diagnosis *** relationships between the gas density and back pressure,nozzle structure,and other key parameters were *** with different characteristics are conducive to meeting the various requirements of LWFA.

关键词： Supersonic gas-jet target Laser wakefield acceleration Electron acceleration Optical interference diagnosis

Positivity of Toeplitz Operators on Harmonic Bergman Space

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Acta Mathematica Sinica,English Series 2016年第2期32卷 175-186页

作者： Yong Lu SHU xian Feng zhao College of Mathematics and Statistics Chongqing University Shanghai Center for Mathematical Sciences Fudan University

In this paper, we study positive Toeplitz operators on the harmonic Bergman space via their Berezin transforms. We consider the Toeplitz operators with continuous harmonic symbols on the closed disk and show that the Toeplitz operator is positive if and only if its Berezin transform is nonnegative on the disk. On the other hand, we construct a function such that the Toeplitz operator with this function as the symbol is not positive but its Berezin transform is positive on the disk. We also consider the harmonic Bergman space on the upper half plane and prove that in this case the positive Toeplitz operators with continuous integrable harmonic symbols must be the zero operator.

关键词： Positive Toeplitz operators harmonic Bergman space Berezin transform

A Review and Prospects on Collaborative Ontology Editing Tools

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Journal of Integrative Agriculture 2012年第5期11卷 731-740页

作者： xian Guo-jian zhao Rui-xue Agricultural Information Institution Chinese Academy of Agricultural SciencesBeijing 10008lPR.China

Building ontology is a fundamental but also hard work. Collaborative ontology editing tools can make ontology development more efficiently. In this paper, the important features of collaborative ontology development were analyzed, and several tools such as AGROVOC Concept Server Workbench （ACSW）, Collaborative Prot6g6 and WebProt6g6 were studied. Besides, some comparisons among them from several aspects were made and some prospects for the further improvement of these tools were given. Finally, we show it is a good way to build agricultural ontology with these tools collaboratively and simultaneously.

关键词： collaborative ontology editing agricultural ontology ACSW Collaborative Prot6g6 WebProt6g6

Quantum Statistical Behaviors of Interaction of an Atomic Bose-Einstein Condensate with Laser

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Communications in Theoretical Physics 2001年第10期36卷 449-454页

作者： YU zhao-xian JIAO Zhi-Yong Theoretical Physics Division Nankai Institute of Mathematics Nankai University Tianjin 300071 China Department of Physics Petroleum University East China Dongying 257061 Shandong Province China Department of Physics Petroleum University East China Dongying 257061 Shandong Province China

We have investigated quantum statistical behaviors of photons and atoms in interaction of an atomic Bose Einstein condensate with quantized laser field. When the quantized laser field is initially prepared in a superposition state which exhibits holes in its photon-number distribution, while the atomic field is initially in a Fock state, it is found that there is energy exchange between photons and atoms. For the input and output states, the photons and atoms may exhibit the sub-Poissonian distribution. The input and output laser fields may exhibit quadrature squeezing, but for the atomic field, only the output state exhibits quadrature squeezing. It is shown that there exists the violation of the Cauchy-Schwartz inequality, which means that the correlation between photons and atoms is nonclassical.

关键词： atomic Bose-Einstein condensate, sub-Poissonian distribution, quadrature squeezing, CauchySchwartz inequality

Comprehensive analysis of the chemical constituents in sulfur-fumigated Lonicerae Japonicae Flos using UHPLC-LTQ-Orbitrap mass spectrometry

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Chinese Journal of Natural Medicines 2020年第2期18卷 148-160页

作者： LIU Zi-Han WANG Yu-Qi MEI xiao-Dan WANG Fei YANG xian-zhao LI xiao-Dong JIANG Feng ZHANG Jia-Yu School of Chinese Pharmacy Beijing University of Chinese MedicineBeijing 102488China BUCM Institute of Liver Diseases Dongzhimen Hospital affiliated to Beijing University of Chinese MedicineBeijing 100700China Department of Hepatology Hubei Provincial Hospital of Traditional Chinese MedicineWuhan 430061China School of Pharmacy Binzhou Medical UniversityYantai 264003China

Lonicerae Japonicae Flos(LJF),a kind of traditional Chinese medicines(TCMs),has functions of detoxifying and evacuating *** the study,a method based on ultra-high performance liquid chromatography coupled with linear ion trap-Orbitrap mass spectrometry(UHPLC-LTQ-Orbitrap MS)was developed for the chemical constituent analysis of organic acids,flavonoids,iridoids and new-generated compounds in sulfur-fumigated LJF(SF-LJF).Based on the accurate mass measurement(<±5 ppm),chromatographic behavior and diagnostic product ions(DPIs),113 constituents were unambiguously or tentatively characterized from SFLJF extract,including 46 chlorogenic acids,19 flavonoids,29 iridoid glycosides and 19 newly-generated compounds(including 17 sulfur-containing derivatives).In addition,5-CQA(5-caffeoylquinic acid,chlorogenic acid)was chosen to be sulfur-fumigated for the result *** was found that the most significant change of LJF after sulfur fumigation was the occurrence of sulfate or sulfite esterification reactions,which resulted in the emergence of many new sulfur-containing *** results demonstrated that the established method was a useful and efficient analytical tool to comprehensively characterize the material basis of SF-LJF,and also an excellent guidance of quality control about LJF.

关键词： Sulfur fumigation Lonicerae Japonicae Flos Chemical components analysis UHPLC-LTQ-Orbitrap MS