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Multimorphism and gap opening of charge-density-wave phases in monolayer VTe2

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Nano Research 2020年第6期13卷 1733-1738页

作者： Meizhuang liu Changwei wu Zizhao liu Zhiqiang Wang Dao-Xin yao Dingyong zhong School of Physics and State Key Laboratory of Optoelectronic Materials and Technologies Sun Yat-sen UniversityGuangzhou510275China

Vanadium dichalcogenides have attracted increasing interests for the charge density wave phenomena and possible ***,we report on the multiphase behavior and gap opening in monolayer VTe2 grown by molecular beam *** tunneling microscopy(STM)and spectroscopy study revealed the(4×4)metallic and gapped(2√3×2√3)charge-density wave(CDW)phases with an energy gap of≈40 *** the in-plane condensation of vanadium atoms,the typical star-of-David clusters and truncated triangle-shaped clusters are formed in the(4×4)and(2√3×2√3)phases respectively,resulting in different surface morphologies and electronic structures as confirmed by density functional theory(DFT)calculations with on-site Coulomb *** CDW-driven reorganization of the atomic structure weakens the ferromagnetic superexchange coupling and strengthens the antiferromagnetic exchange coupling on the contrary,suppressing the long-range magnetic order in monolayer *** electron correlation is found to be important to explain the gap opening in the(2√3×2√3)phase.

关键词： transition-metal dichalcogenides charge density wave 1T-VTe2 scanning tunneling microscopy

基于PI3K/AKT/GSK-3β信号通路探讨EA改善APP/PS1双转基因小鼠认知功能障碍的内在机制

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中国药理学通报 2024年第1期40卷 90-98页

作者：仲丽丽路鑫于颖赵秦妍张静刘彤慧倪雪妍车艳玲吴丹刘宏黑龙江中医药大学黑龙江哈尔滨150040 黑龙江中医药大学附属第一医院黑龙江哈尔滨150040 黑龙江中医药大学基础医学院黑龙江哈尔滨150040

目的探讨鞣花酸(ellagicacid,EA)对APP/PS1双转基因小鼠认知功能的影响,并基于磷脂酰肌醇3-激酶/蛋白激酶B/糖原合成酶激酶-3(PI3K/AKT/GSK-3β)信号通路探讨鞣花酸对双转基因小鼠海马氧化应激水平的调节机制。方法将32只SPF级6月龄APP/... 详细信息

目的探讨鞣花酸(ellagicacid,EA)对APP/PS1双转基因小鼠认知功能的影响,并基于磷脂酰肌醇3-激酶/蛋白激酶B/糖原合成酶激酶-3(PI3K/AKT/GSK-3β)信号通路探讨鞣花酸对双转基因小鼠海马氧化应激水平的调节机制。方法将32只SPF级6月龄APP/PS1双转基因小鼠随机分为4组,即APP/PS1组、APP/PS1+EA组、APP/PS1+LY294002组、APP/PS1+EA+LY294002组,每组8只,另外选取8只SPF级C57BL/6J野生型小鼠(Wildtype)作为空白对照组,即WT组。APP/PS1+EA组给予50mg·kg^(-1)·d^(-1)灌胃EA;APP/PS1+LY294002组予以1.5mg·kg^(-1)·d^(-1)腹腔注射PI3K抑制剂LY294002;APP/PS1+EA+LY294002组予以50mg·kg^(-1)·d^(-1)灌胃EA,同时按1.5mg·kg^(-1)·d^(-1)腹腔注射LY294002;WT组和APP/PS1组于相同时间点灌胃等体积10%二甲基亚砜(DMSO)。每日给药1次,连续给药60天。Morris水迷宫检测小鼠学习和记忆能力,免疫组化、蛋白免疫印迹法检测PI3K、AKT、GSK-3β相关蛋白的表达,透射电镜观察小鼠海马组织超微结构变化。结果与WT组相比,其他四组的逃避潜伏期均增长(P<0.05),穿越平台次数明显减少(P<0.01);APP/PS1组、APP/PS1+LY294002组和APP/PS1+EA+LY294002组中的PI3K、AKT蛋白表达量显著降低(P<0.01),GSK-3β表达量显著升高(P<0.01);APP/PS1+EA组的PI3K表达量降低(P<0.05),AKT表达量显著降低(P<0.01),GSK-3β表达量升高(P<0.05);与WT组相比,APP/PS1组海马神经元细胞数目较少,线粒体结构破坏,大部分线粒体出现肿胀,线粒体的内膜和外模不完整,部分线粒体嵴消失,微管、微丝缠结,排列紊乱,而APP/PS1+EA组神经元细胞数较APP/PS1组增多,线粒体结构较清晰,可见清楚的线粒体嵴,线粒体轻度水肿。微管、微丝排列较整齐有序。结论鞣花酸改善AD模型小鼠的学习和记忆能力、减少海马神经元细胞损伤和凋亡,其作用机制可能是通过调节PI3K、AKT、GSK-3β等相关蛋白降低AD模型小鼠海马氧化应激水平。

关键词： APP/PS1双转基因小鼠阿尔茨海默病鞣花酸磷脂酰肌醇3-激酶蛋白激酶B 糖原合成酶激酶-3

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Four new sesquiterpene derivatives from dendrobium findlayanum

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Chinese Journal of Natural Medicines 2019年第12期17卷 900-905页

作者： yang dan CHENG zhong-Quan ZI Cheng-Ting yang liu DONG Fa-wu HU Jiang-Miao ZHOU Jun State Key Laboratory of Phytochemistry and Plant Resources in West China Kunming Institute of BotanyChinese Academy of SciencesKunming 650201China School of Chemistry and Pharmaceutical Sciences Guangxi Normal UniversityGuilin 541004China Guilin Layn Natural Ingredients Corp. Guilin 541004China

Three new sesquiterpene glycosides with alloaromadendrane and ylangene-derived type aglycones,named dendrofindlayanosides A-C(1-3),one new cyclopacamphane type sesquiterpene named dendrofindlayanobilin A(4),together with five known compounds have been isolated from stems of dendrobium *** structures were determined on the basis of spectroscopic and chemical methods.

关键词： dendrobium findlayanum Sesquiterpene derivatives Alloaromadendrane Cyclopacamphane

Nonlinear Least Squares Estimation of Log-ACD Models

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Acta Mathematicae Applicatae Sinica 2018年第3期34卷 516-533页

作者： Zhao CHEN Wei liu Christina dan WANG wu-qing wu yao-hua wu School of Data Science Fudan UniversityShanghai 200433 China Academy of Mathematics and Systems Science Chinese Academy of SciencesBeijing 100190 China New York University Shanghai Shanghai 200122 China School of Business Renmin University of China Beijing 100872 China department of Statistics and Finance University of Science and Technology of China Hefei 230026 China

This paper studies a nonlinear least squares estimation method for the logarithmic autoregressive conditional duration（Log-ACD） model. We establish the strong consistency and asymptotic normality for our estimator under weak moment conditions suitable for applications involving heavy-tailed distributions. We also discuss inference for the Log-ACD model and Log-ACD models with exogenous variables. Our results can be easily translated to study Log-GARCH models. Both simulation study and real data analysis are conducted to show the usefulness of our results.

关键词： Log-ACD model nonlinear least squares estimation Log-GARCH model heavy-tail

Small Angle X-ray Scattering Study of PS Conformation in Tetrahydrofuran Solvent with Gas Anti-solvent

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Chinese Chemical Letters 2000年第12期11卷 1093-1094页

作者： dan LI Zhi Min liu Guan Ying yang Qing HUO Bu Xing HAN Yi liu zhong Hua wu Bao zhong DONG Center for molecular sciences Institute of chemistryChinese Academy of ScienceBeijing 100080 Chemical Engineering College Beijing Union UniversityBeijing 100023 Institute of High Energy Physics Chinese Academy of ScienceBeijing 100039

Small angle X-ray scattering (SAXS) was used to study the effect of dissolved CO2 on the conformation of polystyrene (PS) in PS/tetrahydrofuran(THF) solution at 308.15 K and at pressures up to 3 MPa. The cloud pressure and the expansion curve of the solution were also determined. The dependence of the conformation on pressure was discussed.

关键词： small angle X-ray scattering polystyrene THF CO2 conformation

Spatial matching and flow in supply and demand of water provision services: A case study in Xiangjiang River Basin

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Journal of Mountain Science 2022年第1期19卷 228-240页

作者： deNG Chu-xiong ZHU Da-mei liu yao-jun LI zhong-wu College of Resources and Environmental Sciences Hunan Normal UniversityChangsha 410081China Hunan Key Laboratory of Geospatial Big Data Mining and Application Changsha 410081China College of Environmental Science and Engineering Hunan UniversityChangsha 410082China

Global climate change and increased human consumption have aggravated the uneven spatiotemporal distribution of watershed water resources, affecting the water provision supply and demand state. However, this problem has often been ignored. The present study used the Xiangjiang River basin(XRB) as the study area, and the Integrated Valuation of Ecosystem Services and Trade-offs(InVEST) model, demand quantification model,supply–demand ratio, and water flow formula were applied to explore the spatial heterogeneity, flow, and equilibrium between water supply and demand. The results demonstrated significant spatial heterogeneity in the upstream, midstream, and downstream *** areas of water shortage were mainly located the downstream of the Changsha–Zhuzhou–Xiangtan urban agglomeration, and the Hengyang basin was the most scarcity area. Affected by terrain gradients and human needs, water flow varied from-16.33 × 10^(8) m^(3) to 13.69 × 10^(8) m^(3)from the upstream to the downstream area, which provided a possibility to reduce spatial heterogeneity. In the future, measures such as strengthening water resource system control,sponge city construction, and dynamic monitoring technology should be taken to balance the supply and demand of water in different river sections of the basin. This study can provide references for regulating water resources allocation in different reaches of the basin.

关键词： Water provision services Supply and demand Spatiotemporal dislocation Water flow Water management and saving policy Xiangjiang River basin

Proteomic and phosphoproteomic profiling of COVID-19-associated lung and liver injury:a report based on rhesus macaques

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Signal Transduction and Targeted Therapy 2022年第2期7卷 375-378页

作者： Jiang-Feng liu Ya-Nan Zhou Shuai-yao Lu Ye-Hong yang Song-Feng wu de-Pei liu Xiao-zhong Peng Jun-Tao yang State Key Laboratory of Medical Molecular Biology Department of Biochemistry and Molecular BiologyInstitute of Basic Medical Sciences Chinese Academy of Medical SciencesSchool of Basic Medicine Peking Union Medical CollegeBeijing 100005China National Kunming High-level Biosafety Primate Research Center Institute of Medical BiologyChinese Academy of Medical Sciences and Peking Union Medical CollegeYunnanChina State Key Laboratory of Medical Molecular Biology Department of Biochemistry and Molecular BiologyMedical Primate Research CenterNeuroscience CenterInstitute of Basic Medical Sciences Chinese Academy of Medical SciencesSchool of Basic Medicine Peking Union Medical CollegeBeijingChina State Key Laboratory of Proteomics Beijing Proteome Research CenterNational Center for Protein Sciences(Beijing)Research Unit of Proteomics&Research and Development of New Drug of Chinese Academy of Medical SciencesInstitute of LifeomicsBeijing 102206China

dear Editor,The ongoing COVID-19 pandemic,caused by severe acute respiratory syndrome conronavirus 2(SARS-CoV-2),has led to over 209,201,939 confirmed cases and 4,390,467 deaths all over the world as of 19 August 2021(https://***/).Novel therapeutic agents and vaccines are desperately needed and mechanism exploration is *** clinical tissues are preferred samples for molecular and mechanism study,COVID-19 clinical tissues are rare and mostly come from autopsies of end-stage patients.1,2 Animal models,especially nonhuman primate models,are therefore constructed for SARS-CoV-2-associated research.

关键词： clinical acute respiratory

Switched enantioselectivity by solvent components and temperature in photocyclodimerization of 2-anthracenecarboxylate with 6~A,6~X-diguanidio-γ-cyclodextrins

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Chinese Chemical Letters 2018年第1期29卷 87-90页

作者： Jigao Yi Wenting Liang Xueqin Wei Jiabin yao Zhiqiang Yan dan Su Zhihui zhong Guowei Gao Wanhua wu Cheng yang Key Laboratory of Green Chemistry & Technology College of Chemistry and state Key Laboratory of Biotherapy West China Medical Center Sichuan University Institute of Environmental Sciences Department of Chemistry Shanxi University

A series of 6A,6X-diguanidio-y-cyclodextrins （CDs） were used as chiral hosts for mediating the enantiodifferentiating [4 ＋4] photocyclodimerization of 2-anthracenecarboxylic acid （AC）. These γ-CD derivatives form stable 1：2 ternary complexes with AC in aqueous ammonia solutions and the head-to- head photodimers 3 and 4 were greatly enhanced in the presence of these diguanidio-γ-CDs. The enantioselectivity ofchiral photodimers 2 and 3 is a critical function of the temperature and the ammonia contents, showinz inverted oroduct chiralitv by chanzinz these external factors.

关键词： CyclodextrinsPhotocyclodimerizationAnthracenecarboxylic acidSupramolecular complexationSolvent effect

基于主要药效成分统计的两面针最佳采收期与合理药用部位研究

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中国中药杂志 2024年第11期49卷 2889-2896页

作者：蒙兰花马庆贡保草姚英刘信丹马志国曹晖张英吴孟华暨南大学岭南传统中药研究中心/国家中药现代化工程技术研究中心岭南资源分中心/广东省中医药信息化重点实验室广东广州510632 华润三九医药股份有限公司广东深圳518110 佛山科学技术学院广东佛山528051

通过分析不同生长年限、不同采收月份、不同部位的两面针栽培品主要药效成分含量的变化规律,并与野生品比较,确定两面针的最佳采收期和合理药用部位。采用高效液相色谱法(HPLC),色谱柱为Kinetex C_(18)(4.6 mm×100 mm,2.6μm),流动相为... 详细信息

通过分析不同生长年限、不同采收月份、不同部位的两面针栽培品主要药效成分含量的变化规律,并与野生品比较,确定两面针的最佳采收期和合理药用部位。采用高效液相色谱法(HPLC),色谱柱为Kinetex C_(18)(4.6 mm×100 mm,2.6μm),流动相为0.2%三乙胺的0.3%磷酸水溶液-乙腈(80∶20),流速1.0 m L·min^(-1),检测波长273 nm,柱温30℃,以主要药效成分氯化两面针碱和白屈菜红碱为指标,对两面针样品进行含量测定。结果表明野生与栽培两面针根的主要药效成分含量无显著性差异,栽培两面针根与根+茎无显著性差异;由层次聚类分析(HCA)与主成分分析(PCA)结果说明两面针根与茎能明显区分,但无法区分野生与栽培品,与显著性分析结果一致;1~6年两面针根的氯化两面针碱和白屈菜红碱质量分数之和为0.114%~0.256%,茎0.030%~0.133%,主要药效成分含量与生长年限呈正相关;4个季节采样均无显著性差异,说明采收季节对两面针主要药效成分含量无影响;3个种植基地的两面针(不含枝)以干燥品计算氯化两面针碱和白屈菜红碱含量之和,云浮为0.308%±0.123%,茂名为0.192%±0.025%,南宁为0.197%±0.052%,3个种植基地均≥0.15%,即移栽2年6个月以上的两面针同时以根(含须根、主根和地下茎)和茎(地上茎)入药可满足要求。综上,两面针栽培品可以作为两面针野生品的合理替代,为实现两面针资源的可持续开发与应用提供保障;根与茎均可作为两面针的药用部位,建议《中国药典》两面针的药用部位修订为干燥根和茎,全年均可采挖。为保障有效成分含量及临床有效性,建议采收移栽3年以上的两面针根和茎入药。

关键词：两面针氯化两面针碱白屈菜红碱含量测定茎