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Integrated spatial metabolomics and transcriptomics decipher the hepatoprotection mechanisms of wedelolactone and demethylwedelolactone on non-alcoholic fatty liver disease
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作者 Panpan Chen Zihan Zhu +8 位作者 Haoyuan Geng Xiaoqing Cui Yuhao Han Lei Wang yaqi zhang Heng Lu Xiao Wang Yun zhang Chenglong Sun 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2024年第4期552-561,共10页
Eclipta prostrata L.has been used in traditional medicine and known for its liver-protective properties for centuries.Wedelolactone(WEL)and demethylwedelolactone(DWEL)are the major coumarins found in E.prostrata L.How... Eclipta prostrata L.has been used in traditional medicine and known for its liver-protective properties for centuries.Wedelolactone(WEL)and demethylwedelolactone(DWEL)are the major coumarins found in E.prostrata L.However,the comprehensive characterization of these two compounds on non-alcoholic fatty liver disease(NAFLD)still remains to be explored.Utilizing a well-established zebrafish model of thioacetamide(TAA)-induced liver injury,the present study sought to investigate the impacts and mechanisms of WEL and DWEL on NAFLD through integrative spatial metabolomics with liver-specific transcriptomics analysis.Our results showed that WEL and DWEL significantly improved liver function and reduced the accumulation of fat in the liver.The biodistributions and metabolism of these two compounds in whole-body zebrafish were successfully mapped,and the discriminatory endogenous metabolites reversely regulated by WEL and DWEL treatments were also characterized.Based on spatial metabolomics and transcriptomics,we identified that steroid biosynthesis and fatty acid metabolism are mainly involved in the hepatoprotective effects of WEL instead of DWEL.Our study unveils the distinct mechanism of WEL and DWEL in ameliorating NAFLD,and presents a“multi-omics”platform of spatial metabolomics and liver-specific transcriptomics to develop highly effective compounds for further improved therapy. 展开更多
关键词 Spatial metabolomics TRANSCRIPTOMICS Non-alcoholic fatty liver disease Wedelolactone Demethylwedelolactone
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The Effect of Self-Investment on Hoarding Tendency of Chinese College Students:Role of Psychological Connections
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作者 Xiangli Guan Yue zhang +6 位作者 Yang Li yaqi zhang Jingjing Wang Xuejiao Li Mary C.Jobe Md Zahir Ahmed Oli Ahmed 《International Journal of Mental Health Promotion》 2023年第6期755-766,共12页
Because of factors such as energy and time one invests in an object,the stronger the connection,value,and reluc-tance to lose said object individual will have.Hoarding behavior arises when individuals incorporate a st... Because of factors such as energy and time one invests in an object,the stronger the connection,value,and reluc-tance to lose said object individual will have.Hoarding behavior arises when individuals incorporate a strong attachment with themselves to an object.The purpose of this study is to examine the effect of self-investment on hoarding tendency and the roles of possession-self link and liking level in this connection.A hypothetical model of the relationship between self-investment,possession-self link,liking level,and hoarding tendency was tested.A convenience sampling method was used to survey 450 college students in Yunnan Province on either a paper-based or online self-report scale.The data were collected using self-investment,possession-self link,and liking level questionnaires,as well as the Saving Inventory Revised.Results showed positive relationship between the study variables,ranging from 0.37 to 0.87.College students’self-investment had a direct positive pre-dictive effect on hoarding tendency;self-investment,in turn,indirectly predicted hoarding tendency through the mediating effect of possession-self link;and individual liking level of items had a moderating effect for self-invest-ment on the possession-self link.This study shows how self-investment affects the hoarding tendency of college students,and the results of this study also help demonstrate the value of self-investment and possession-self link in optimizing students’hoarding tendency and thus promoting good psychological status. 展开更多
关键词 Hoarding tendency self-investment psychological connections possession-self link liking level
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Comprehensive analysis of NAC transcription factors and their expression during fruit spine development in cucumber (Cucumis sativus L.) 被引量:14
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作者 Xingwang Liu Ting wang +8 位作者 Ezra Bartholomew Kezia Black Mingming Dong yaqi zhang Sen Yang Yanling Cai Shudan Xue Yiqun Weng Huazhong Ren 《Horticulture Research》 SCIE 2018年第1期556-569,共14页
The cucumber(Cucumis sativus L.)is an important vegetable crop worldwide,and fruit trichomes or spines are an important trait for external fruit quality.The mechanisms underlying spine formation are not well understoo... The cucumber(Cucumis sativus L.)is an important vegetable crop worldwide,and fruit trichomes or spines are an important trait for external fruit quality.The mechanisms underlying spine formation are not well understood,but the plant-specific NAC family of transcription factors may play important roles in fruit spine initiation and development.In this study,we conducted a genome-wide survey and identified 91 NAC gene homologs in the cucumber genome.Clustering analysis classified these genes into six subfamilies;each contained a varying number of NAC family members with a similar intron–exon structure and conserved motifs.Quantitative real-time PCR analysis revealed tissue-specific expression patterns of these genes,including 10 and 12 that exhibited preferential expression in the stem and fruit,respectively.Thirteen of the 91 NAC genes showed higher expression in the wild-type plant than in its near-isogenic trichome mutant,suggesting their important roles in fruit spine development.Exogenous application of four plant hormones promoted spine formation and increased spine density on the cucumber fruits;several NAC genes showed differential expression over time in response to phytohormone treatments on cucumber fruit,implying their essential roles in fruit-trichome development.Among the NAC genes identified,12 were found to be targets of 13 known cucumber micro-RNAs.Collectively,these findings provide a useful resource for further analysis of the interactions between NAC genes and genes underlying trichome organogenesis and development during fruit spine development in cucumber. 展开更多
关键词 development. analysis SPINE
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亲水性添加剂二甲基甲酰胺对聚酰胺反渗透膜性能的影响 被引量:3
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作者 于翔 张雅琪 +3 位作者 李玘璇 王延伟 赵俊杰 赵珂 《高分子材料科学与工程》 EI CAS CSCD 北大核心 2018年第2期71-75,共5页
详细研究了在间苯二胺(MPD)水相中添加亲水性溶剂二甲基甲酰胺(DMF)对聚酰胺复合膜表面形貌和分离性能的影响。随着DMF浓度的增加,聚酰胺分离层表面逐渐形成连续扁平的片状结构,厚度和表面粗糙度均逐渐减小。尤其是DMF的加入能够在提高... 详细研究了在间苯二胺(MPD)水相中添加亲水性溶剂二甲基甲酰胺(DMF)对聚酰胺复合膜表面形貌和分离性能的影响。随着DMF浓度的增加,聚酰胺分离层表面逐渐形成连续扁平的片状结构,厚度和表面粗糙度均逐渐减小。尤其是DMF的加入能够在提高复合膜通量的同时避免截留率大幅降低。其原因是DMF一方面降低了MPD向有机相中的扩散速率,另一方面促进了聚合反应的进行,致使MPD与均苯三甲酰氯(TMC)只能在更薄的区域内反应,从而最终形成更薄的聚酰胺分离层,以及层内更加扁平连续的片状结构。 展开更多
关键词 反渗透膜 聚酰胺 二甲基甲酰胺 亲水性添加剂 界面聚合
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化妆品乳液及乳化新技术(Ⅴ)——脂质体包载技术在经皮输送中的应用 被引量:1
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作者 张雅琪 梁蓉 杨成 《日用化学工业》 CAS 北大核心 2021年第10期939-948,共10页
化妆品中所添加的活性成分往往存在光、热稳定性差,溶解性差等原因,需通过包载技术提高其生物利用度。在各种包载体系中,脂质体由于结构与人体皮肤细胞相似,且具有良好的生物相容性,是一种有效的包载方法。然而传统脂质体由于稳定性、... 化妆品中所添加的活性成分往往存在光、热稳定性差,溶解性差等原因,需通过包载技术提高其生物利用度。在各种包载体系中,脂质体由于结构与人体皮肤细胞相似,且具有良好的生物相容性,是一种有效的包载方法。然而传统脂质体由于稳定性、可变形性差等原因难以通过皮肤屏障,达到促渗效果。如今,通过改变传统脂质体磷脂双层膜的结构获得了各种新型脂质体,如醇质体、类脂质体、传递体、磷脂复合物、甘油体等,新型脂质体由于稳定性良好、具有可变形性、可改变角质层脂质结构等特点,能够改善药物经皮输送效果。文章综述了几种新型脂质体,并对其透皮效果进行分析,旨在为化妆品包载领域提供借鉴和思路。 展开更多
关键词 脂质体 透皮 化妆品
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场景抽象语义综合模型及其在红外弱小目标检测中的应用
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作者 李少毅 张雅淇 +4 位作者 程岳 杨曦 张良 林健 孟中杰 《航空学报》 EI CAS CSCD 北大核心 2024年第20期167-183,共17页
多任务、跨域复杂环境下弱小目标准确、稳定检测在红外预警、搜索与跟踪、精确制导等领域具有重要作用。针对当前算法过于依赖人工设计策略与先验知识,以提取目标信息为目的,对于场景信息的挖掘和利用不充分,性能受限且环境适应性不足... 多任务、跨域复杂环境下弱小目标准确、稳定检测在红外预警、搜索与跟踪、精确制导等领域具有重要作用。针对当前算法过于依赖人工设计策略与先验知识,以提取目标信息为目的,对于场景信息的挖掘和利用不充分,性能受限且环境适应性不足等问题,提出了基于场景抽象语义综合的弱小目标检测方法。首先,利用交叉注意力、孪生网络、扩展语义图和自学习双通道的方法设计了4种场景抽象语义综合模型。接着,基于4种语义综合模型设计了基于场景语义综合的弱小目标检测网络,将场景类别语义信息引入到红外弱小目标检测过程实现多类复杂背景下红外弱小目标检测。最后,实验结果表明提出的基于自学习双通道语义综合的弱小目标检测算法精确度到达84.24%,召回率达到89.68%。 展开更多
关键词 场景语义 语义综合 图像处理 深度学习 红外弱小目标检测
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Network pharmacology-based analysis of the mechanism of Radix Paeoniae Alba against Toosendan Fructus-induced hepatotoxicity
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作者 Heng Xu yaqi zhang +1 位作者 Huan Chen Tengfei Bai 《Gastroenterology & Hepatology Research》 2022年第1期19-24,共6页
Objective:Objective:To analyze and explore the key targets and molecular mechanisms of action of Radix Paeoniae Alba against Toosendan Fructus-induced hepatotoxicity and the relationship between corresponding compound... Objective:Objective:To analyze and explore the key targets and molecular mechanisms of action of Radix Paeoniae Alba against Toosendan Fructus-induced hepatotoxicity and the relationship between corresponding compounds based on network pharmacology.Methods:Using network pharmacology,a"traditional Chinese medicine-chemical composition-key target-pathway"analysis was conducted on Radix Paeoniae Alba for the treatment of Toosendan Fructus-induced hepatotoxicity.The possible mechanism of action was analyzed in terms of function.Results:The core targets,such as interleukin(IL)-6,tumor necrosis factor(TNF),heat shock protein 90 alpha family class A member 1(HSP90AA1),peroxisome proliferator-activated receptor gamma(PPARG),prostaglandin-endoperoxide synthase 2(PTGS2),heme oxygenase 1(HMOX1),Jun proto-oncogene(JUN),caspase-3,estrogen receptor 1(ESR1),and aryl hydrocarbon receptor(AHR)were screened from the targets of Radix Paeoniae Alba against Toosendan Fructus-induced hepatotoxicity.Biological process(BP)of toxic targets(BP terms)involved"response to drug;activation of cysteine-type endopeptidase activity involved in apoptotic process,”positive regulation of transcription.Cellular components(CC terms)mainly involved cytosol and membrane rafts.Molecular function(MF)terms included"protein homodimerization activity,"RNA polymerase II transcription factor activity and enzyme binding,etc."The Kyoto Encyclopedia of Genes and Genomes(KEGG)pathway included the TNF signaling pathway,cancer pathways,and apoptosis.Conclusion:Radix Paeoniae Alba might alleviate Toosendan Fructus-induced hepatotoxicity through IL6,TNF,HSP90AA1,PPARG,PTGS2,HMOX1,and other targets,possibly via the activation of cysteine-type endopeptidase activity involved in these pathways. 展开更多
关键词 Radix Paeoniae Alba Toosendan Fructus liver toxicity network pharmacology compatibility
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一氧化氮与肝缺血再灌注损伤相关性研究新进展
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作者 张亚奇 丁宁 +3 位作者 向圆圆 曾永芬 洪芬芳 杨树龙 《药物资讯》 2017年第5期101-107,共7页
肝缺血再灌注损伤(hepatic ischemia reperfusion injury, HIRI)时,体内NO、eNOS减少,iNOS增多。NO减少时,肝窦收缩微循环障碍;肝脏细胞水肿、坏死、凋亡;亚硝酸盐还原为NO增多。NO涉及HIRI的多个环节。损伤早期,eNOS激活产生NO有保护作... 肝缺血再灌注损伤(hepatic ischemia reperfusion injury, HIRI)时,体内NO、eNOS减少,iNOS增多。NO减少时,肝窦收缩微循环障碍;肝脏细胞水肿、坏死、凋亡;亚硝酸盐还原为NO增多。NO涉及HIRI的多个环节。损伤早期,eNOS激活产生NO有保护作用,但eNOS过度表达且其衍生NO生物利用度过高可加重肝损伤;而iNOS晚期因大量产生NO产生保护作用。缺血预处理、缺血后处理以及药物预处理则可通过增强eNOS、降低iNOS活性而增加血清NO并降低丙二醛含量,发挥肝脏围术期保护功能。本文综述了近年来NO与HIRI相关性新研究进展。 展开更多
关键词 肝脏 缺血再灌注损伤 一氧化氮 一氧化氮合酶
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单分子结中的有机自由基
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作者 张雅琦 邱仁慧 +3 位作者 屈恺 张成 J.Fraser Stoddart 陈洪亮 《Science China Materials》 SCIE EI CAS CSCD 2024年第3期709-728,共20页
空气稳定有机自由基的发现引起了人们对探究其在分子电子学和自旋电子学中应用的兴趣.这些自由基具有独特的开壳层电子结构,因而表现出特殊的电学特性.由于其较弱的旋轨耦合特性,也使得其成为自旋电子学的重要研究对象.此外,自由基还可... 空气稳定有机自由基的发现引起了人们对探究其在分子电子学和自旋电子学中应用的兴趣.这些自由基具有独特的开壳层电子结构,因而表现出特殊的电学特性.由于其较弱的旋轨耦合特性,也使得其成为自旋电子学的重要研究对象.此外,自由基还可以通过二聚、分子识别和机械互锁等分子间相互作用来构筑超分子器件.本文综述了空气稳定有机自由基在电子学及自旋电子学中的应用,通过详述其卓越的电磁性能来拓展启发分子设计的多样性.本综述还概述了超分子自由基的制备方法和相关性质的研究进展,拓宽了单分子研究的范围.此外,自由基介导的单分子反应是一个新兴的研究方向,本文也对该领域的未来发展方向进行了展望.通过阐明空气稳定有机自由基的应用潜力,本文将有望对分子电子学和自旋电子学的研究产生一定的指导意义. 展开更多
关键词 air-stable radicals molecular electronics SPINTRONICS supramolecular devices
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High-performance ultrathin Ag electrodes by chemical bond anchoring Ag atoms for stretchable organic light-emitting devices
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作者 Yue Qin Yawei Wang +6 位作者 Xinxin Wang yaqi zhang Jiahao Xu Kanchi Dong Yuehua Chen Wenyong Lai Xinwen zhang 《Nano Research》 SCIE EI CSCD 2024年第8期7614-7620,共7页
The progress of stretchable organic light-emitting devices(OLEDs)has brought about new possibilities for highly functional wearable electronics.However,the efficiency and durability of stretchable OLEDs have been limi... The progress of stretchable organic light-emitting devices(OLEDs)has brought about new possibilities for highly functional wearable electronics.However,the efficiency and durability of stretchable OLEDs have been limited by the performance of stretchable transparent electrodes.Here,we proposed an interface engineering strategy that involves anchoring the growth of silver(Ag)atoms with amine-enriched biomaterials for high-quality stretchable transparent electrodes.The strong interactions between the Ag atom and the amine group enable the uniform Ag electrodes at an ultralow thickness of 7 nm,and provide remarkable mechanical flexibility and strain endurance to the Ag electrodes.The distinct effects of different amino acids were investigated,and a deep understanding of their unique contributions to the film formation process was gained.The resulting ultrathin Ag electrodes exhibit outstanding optoelectrical properties(transmittance of~98% and sheet resistance of~8.7Ω/sq)and excellent stretchability during 500 stretching cycles at 100%strain.Stretchable green phosphorescent OLEDs based on the Ag electrodes have been demonstrated with a current efficiency of up to~70.4 cd/A.Impressively,the devices show excellent stretching stability,retaining~89% of the original luminance and~78% of the original current efficiency after 200 stretching cycles at 100%strain.This work opens up new possibilities for stretchable transparent electrodes,fostering advancements in wearable displays and other innovative flexible devices. 展开更多
关键词 transparent flexible electrodes ultrathin metal film interface mechanical stability
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Nitrogen-doped carbon dots-modified Prussian blue with sandwichlike structure as a high-performance electrochromic material
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作者 yaqi zhang Lide Li +6 位作者 Siming Zhao Yilin Ding Nan Shen Yujie Sun Hao Wang Jingfa Li Rufan zhang 《Nano Research》 SCIE EI CSCD 2024年第10期9174-9180,共7页
Prussian blue(PB),as a promising inorganic electrochromic material(ECM),has been widely used in smart windows,displays,sensors,etc.However,there are still many challenges for PB to achieve high electrochromic performa... Prussian blue(PB),as a promising inorganic electrochromic material(ECM),has been widely used in smart windows,displays,sensors,etc.However,there are still many challenges for PB to achieve high electrochromic performance.Herein,we synthesized nitrogen-doped carbon dots-modified PB film(defined as PB@N-CDs)with a sandwich-like structure by a simple stepwise electrodeposition method.The carbon dots show an obvious advantage in ultrafast electron transfer ability,which can reduce charge loss during the transfer process,improve the electrochemical activity on both sides of PB,and thus facilitate a rapid electrochromic response.Furthermore,the surface of nitrogen-doped carbon dots contains multiple organic functional groups,which widen the movement path of K+ions under electrostatic adsorption.Impressively,the PB@N-CDs film exhibits a short bleaching/coloring time(0.5/0.9 s)and a superior optical modulation range(78.6%).Particularly,the coloring efficiency has been significantly improved to 137.71 cm^(2)/C(at 700 nm).All of these results open up new avenues for developing highperformance PB-based ECMs and promoting their applications in corresponding electrochromic devices(ECDs)and smart windows. 展开更多
关键词 electrochromic Prussian blue carbon dots NANOSTRUCTURE
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Optimization of microstructure design for enhanced sensing performance in flexible piezoresistive sensors
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作者 Xinghao Fan Hailong Hu +2 位作者 Bin Liao yaqi zhang Fan zhang 《Journal of Advanced Ceramics》 SCIE EI CAS CSCD 2024年第6期711-728,共18页
Flexible piezoresistive strain sensors have received significant attention due to their diverse applications in monitoring human activities and health,as well as in robotics,prosthetics,and human–computer interaction... Flexible piezoresistive strain sensors have received significant attention due to their diverse applications in monitoring human activities and health,as well as in robotics,prosthetics,and human–computer interaction interfaces.Among the various flexible sensor types,those with microstructure designs are considered promising for strain sensing due to their simple structure,high sensitivity,extensive operational range,rapid response time,and robust stability.This review provides a concise overview of recent advancements in flexible piezoresistive sensors based on microstructure design for enhanced strain sensing performance,including the impact of microstructure on sensing mechanisms,classification of microstructure designs,fabrication methods,and practical applications.Initially,this review delves into the analysis of piezoresistive sensor sensing mechanisms and performance parameters,exploring the relationship between microstructure design and performance enhancement.Subsequently,an in-depth discussion is presented,focusing on the primary themes of microstructure design classification,process selection,performance characteristics,and specific applications.This review employs mathematical modeling and hierarchical analysis to emphasize the directionality of different microstructures on performance enhancement and to highlight the performance advantages and applicable features of various microstructure types.In conclusion,this review examines the multifunctionality of flexible piezoresistive sensors based on microstructure design and addresses the challenges that still need to be overcome and improved,such as achieving a wide range of stretchability,high sensitivity,and robust stability.This review summarizes the research directions for enhancing sensing performance through microstructure design,aiming to assist in the advancement of flexible piezoresistive sensors. 展开更多
关键词 microstructure design sensing performance flexible piezoresistive strain sensors microsensing mechanism
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Notch signaling pathway in cancer:from mechanistic insights to targeted therapies
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作者 Qingmiao Shi Chen Xue +7 位作者 Yifan Zeng Xin Yuan Qingfei Chu Shuwen Jiang Jinzhi Wang yaqi zhang Danhua Zhu Lanjuan Li 《Signal Transduction and Targeted Therapy》 SCIE CSCD 2024年第6期2527-2563,共37页
Notch signaling,renowned for its role in regulating cell fate,organ development,and tissue homeostasis across metazoans,is highly conserved throughout evolution.The Notch receptor and its ligands are transmembrane pro... Notch signaling,renowned for its role in regulating cell fate,organ development,and tissue homeostasis across metazoans,is highly conserved throughout evolution.The Notch receptor and its ligands are transmembrane proteins containing epidermal growth factor-like repeat sequences,typically necessitating receptor-ligand interaction to initiate classical Notch signaling transduction.Accumulating evidence indicates that the Notch signaling pathway serves as both an oncogenic factor and a tumor suppressor in various cancer types.Dysregulation of this pathway promotes epithelial-mesenchymal transition and angiogenesis in malignancies,closely linked to cancer proliferation,invasion,and metastasis.Furthermore,the Notch signaling pathway contributes to maintaining stem-like properties in cancer cells,thereby enhancing cancer invasiveness.The regulatory role of the Notch signaling pathway in cancer metabolic reprogramming and the tumor microenvironment suggests its pivotal involvement in balancing oncogenic and tumor suppressive effects.Moreover,the Notch signaling pathway is implicated in conferring chemoresistance to tumor cells.Therefore,a comprehensive understanding of these biological processes is crucial for developing innovative therapeutic strategies targeting Notch signaling.This review focuses on the research progress of the Notch signaling pathway in cancers,providing in-depth insights into the potential mechanisms of Notch signaling regulation in the occurrence and progression of cancer.Additionally,the review summarizes pharmaceutical clinical trials targeting Notch signaling for cancer therapy,aiming to offer new insights into therapeutic strategies for human malignancies. 展开更多
关键词 NOTCH INVASION INVOLVEMENT
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植物HIPP家族蛋白结构和功能研究进展
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作者 张雅琦 戎福喜 +3 位作者 沈雨欣 洪哲源 张蓝天 武亮 《植物学报》 CAS CSCD 北大核心 2024年第4期659-670,共12页
重金属相关异戊二烯化植物蛋白HIPP是一类含有金属结合结构域(HMA)和C端异戊二烯化基序的金属伴侣蛋白。该文总结了模式植物中HIPP蛋白的结构特征,阐述了植物HIPP蛋白家族参与的重金属稳态和解毒机制,揭示了其在植物生长发育和应对环境... 重金属相关异戊二烯化植物蛋白HIPP是一类含有金属结合结构域(HMA)和C端异戊二烯化基序的金属伴侣蛋白。该文总结了模式植物中HIPP蛋白的结构特征,阐述了植物HIPP蛋白家族参与的重金属稳态和解毒机制,揭示了其在植物生长发育和应对环境变化(生物和非生物胁迫)中的潜在意义,以期为HIPP蛋白家族的后续研究提供启示。 展开更多
关键词 HIPPs HMA 重金属
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Development of sterically hindered SPOs and enantioselective Ni-Al bimetallic catalyzed C-H cyclization of 4-oxoquinazolines with tethered alkenes
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作者 yaqi zhang Qiang Ni +2 位作者 Bendu Pan Long Jiang Liqin Qiu 《Chinese Chemical Letters》 SCIE CAS CSCD 2023年第6期366-370,共5页
The Ni-Al bimetallic catalysis of intramolecular enantioselective and regioselective C-H cyclization of4-oxoquinazolines with tethered alkenes has been successfully developed.Some new secondary phosphine oxides(SPOs)w... The Ni-Al bimetallic catalysis of intramolecular enantioselective and regioselective C-H cyclization of4-oxoquinazolines with tethered alkenes has been successfully developed.Some new secondary phosphine oxides(SPOs)with large steric hindrance(SPO6-11)were designed and successfully synthesized from readily available chiral amines or amino acids.The developed chiral SPOs as ligands or preligands demonstrate much higher efficiency in the asymmetric catalytic reactions than the reported traditional ones.A new class of chiral tricyclic pyrroloquinazolinones were obtained in up to 95%yield and 99%ee. 展开更多
关键词 Ni-Al bimetallic catalysis Secondary phosphine oxides C-H cyclization Asymmetric catalysis 4-Oxoquinazolines
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双金属Ag-Ni-MOF-74的合成及低温CO催化还原NO性能研究 被引量:4
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作者 张雅祺 楚奇 +4 位作者 石勇 高金索 熊巍 黄磊 丁越 《化学学报》 SCIE CAS CSCD 北大核心 2021年第3期361-368,共8页
采用后合成修饰法成功制备出一系列双金属Agx-Ni-MOF-74催化剂,并应用于CO选择性催化还原NO(CO-SCR)反应.研究结果发现,相较于单金属Ni-MOF-74催化剂,双金属Ag-Ni-MOF-74具有更加优良的低温CO催化还原NO能力,其中Ag1-Ni-MOF-74催化剂在2... 采用后合成修饰法成功制备出一系列双金属Agx-Ni-MOF-74催化剂,并应用于CO选择性催化还原NO(CO-SCR)反应.研究结果发现,相较于单金属Ni-MOF-74催化剂,双金属Ag-Ni-MOF-74具有更加优良的低温CO催化还原NO能力,其中Ag1-Ni-MOF-74催化剂在200~300℃的温度范围达到接近100%NO转化率.利用X射线衍射分析(XRD)、傅氏转换红外线光谱分析(FT-IR)、场发射扫描电子显微镜(SEM)、X射线光电子能谱(XPS)、氢气程序升温还原性能测试(H_(2)-TPR)等技术对样品的结构和性能进行了探究,发现Ag的加入有利于丰富催化剂活性位点和提高催化剂的比表面积,并促进反应物的有效活化和传输.此外,基于原位红外光谱分析,发现了CO-SCR反应过程遵循具有较高低温催化效率的Langmuir-Hinshelwood(L-H)机理. 展开更多
关键词 脱硝 双金属有机骨架 Ag-Ni-MOF-74 后合成修饰法 CO选择性催化还原NO(CO-SCR)
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X-ray scintillation in lead-free double perovskite crystals 被引量:10
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作者 Qingsong Hu Zhenzhou Deng +6 位作者 Manchen Hu Anjiang Zhao yaqi zhang Zhifang Tan Guangda Niu Haodi Wu Jiang Tang 《Science China Chemistry》 SCIE EI CAS CSCD 2018年第12期1581-1586,共6页
Metal halide perovskites have shown great performance for various applications,including solar cells,light emitting diodes,and radiation detectors,but they still suffer from the toxicity of lead and instability.Here w... Metal halide perovskites have shown great performance for various applications,including solar cells,light emitting diodes,and radiation detectors,but they still suffer from the toxicity of lead and instability.Here we report the use of lanthanide series as trivalent metals to obtain low toxicity and highly stable double perovskites(Cs_2NaLnCl_6,Ln=Tb or Eu)with high scintillation light yield.The crystals exhibit typical f-f transitions of lanthanide cations,while Cs_2NaTbCl_6exhibits strong green photoluminescence,and Cs_2NaEuCl_6exhibits red photoluminescence.Under X-ray radiations,the light yield of Cs_2NaTbCl_6reaches46600 photons MeV^(-1),much higher than that of the commercially used(Lu,Y)_2SiO_5:Ce^(3+)crystals(LYSO,28500 photons MeV^(-1)),and previously reported lead-based perovskites(14000 photons MeV^(-1)).As a new member of lead-free perovskites,lanthanide-based double perovskites open up a new route toward radiation detections and potential medical imaging. 展开更多
关键词 low TOXIC scintillation light YIELD LANTHANIDE double perovskites
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A potential red-emitting phosphor Ca_(2)YTaO_(6):Eu^(3+):Luminescence properties,thermal stability and applications for white LEDs 被引量:7
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作者 Ka Ding Siru A +5 位作者 Shuo Pang Leyan Shan yaqi zhang Pengfei Sun Bin Deng Ruijin Yu 《Journal of Rare Earths》 SCIE EI CAS CSCD 2021年第7期749-756,I0001,共9页
A novel red-emitting phosphor tantalate Ca_(2)YTaO_(6):Eu^(3+)was synthesized by a solid-state reaction.The purity and surface morphology of the phosphors were characterized.The Ca_(2)YTaO_(6):Eu^(3+)phosphors show a ... A novel red-emitting phosphor tantalate Ca_(2)YTaO_(6):Eu^(3+)was synthesized by a solid-state reaction.The purity and surface morphology of the phosphors were characterized.The Ca_(2)YTaO_(6):Eu^(3+)phosphors show a sharp emission peak at 612 nm under near-ultraviolet(n-UV) at 395 nm because of the ^(5)D0→^(7)F_(2) transition of Eu^(3+).The optimal Eu^(3+)doping concentration in Ca_(2)YTaO_(6) is 40 mol% and the critical energy-transfer distance of Eu^(3+)ions was calculated to be 0.9 nm.The emission spectra of Ca_(2)YTaO_(6):Eu_(3+)from 300 to 480 K were investigated.The thermal-quenching temperature(T_(0.5)) of Ca_(2)YTaO_(6):Eu^(3+)is above 480 K.The color purity of Ca_(2)YTaO_(6):40 mol%Eu^(3+)is as high as 99.8%.The luminescence lifetime of Ca_(2)YTaO_(6):40 mol%Eu^(3+)was also discussed.The high color purity and high thermal stability of Eu^(3+)-doped Ca_(2)YTaO_(6) phosphors contribute to its application value in white lightemitting diodes(w-LEDs). 展开更多
关键词 Luminescence TANTALATE Ca_(2)YTaO_(6):Eu^(3+) Light-emitting diodes Rare earths
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The upregulated intestinal folate transporters direct the uptake of ligand-modified nanoparticles for enhanced oral insulin delivery 被引量:4
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作者 Jingyi Li yaqi zhang +9 位作者 Miaorong Yu Aohua Wang Yu Qiu Weiwei Fan Lars Hovgaard Mingshi Yang Yiming Li Rui Wang Xiuying Li Yong Gan 《Acta Pharmaceutica Sinica B》 SCIE CAS CSCD 2022年第3期1460-1472,共13页
Transporters are traditionally considered to transport small molecules rather than large-sized nanoparticles due to their small pores.In this study,we demonstrate that the upregulated intestinal transporter(PCFT),whic... Transporters are traditionally considered to transport small molecules rather than large-sized nanoparticles due to their small pores.In this study,we demonstrate that the upregulated intestinal transporter(PCFT),which reaches a maximum of 12.3-fold expression in the intestinal epithelial cells of diabetic rats,mediates the uptake of the folic acid-grafted nanoparticles(FNP).Specifically,the upregulated PCFT could exert its function to mediate the endocytosis of FNP and efficiently stimulate the traverse of FNP across enterocytes by the lysosome-evading pathway,Golgi-targeting pathway and basolateral exocytosis,featuring a high oral insulin bioavailability of 14.4%in the diabetic rats.Conversely,in cells with relatively low PCFT expression,the positive surface charge contributes to the cellular uptake of FNP,and FNP are mainly degraded in the lysosomes.Overall,we emphasize that the upregulated intestinal transporters could direct the uptake of ligand-modified nanoparticles by mediating the endocytosis and intracellular trafficking of ligand-modified nanoparticles via the transporter-mediated pathway.This study may also theoretically provide insightful guidelines for the rational design of transporter-targeted nanoparticles to achieve efficient drug delivery in diverse diseases. 展开更多
关键词 Ligand-modified nanoparticles TRANSPORTER Proton-coupled folate transporter Expression level ENDOCYTOSIS Intracellular trafficking Diabetes Oral insulin delivery
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Study on lightning protection scheme of multi-terminal MMC-MVDC distribution system 被引量:2
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作者 Yuqun Gao Yongxia Han +5 位作者 Fanglei Xiao Changfu Chen Jinghan zhang Jie zhang yaqi zhang Licheng Li 《High Voltage》 SCIE EI 2020年第5期605-613,共9页
Based on a±10 kV three-terminal MMC-MVDC(medium voltage DC distribution system based on modular multilevel converter)system,in this study,the authors mainly study on the influencing factors and protection schemes... Based on a±10 kV three-terminal MMC-MVDC(medium voltage DC distribution system based on modular multilevel converter)system,in this study,the authors mainly study on the influencing factors and protection schemes of the lightning intruding overvoltage(including direct lightning and back-flashover lightning).Firstly,a lightning intruding overvoltage simulation model of the MMC-MVDC distribution system using overhead lines is established based on the PSCAD/EMTDC program.The influence of steady-state operating voltage and the number of converter stations on the simulation results are simulated and analysed.Meanwhile,the proper simulation modelling method of the lightning intruding overvoltage for multi-terminal MMC-MVDC system is proposed.Secondly,the lightning intruding overvoltage is simulated when the line is struck by the lightning stroke current that occurs once in 20 years and the different lightning protection schemes are proposed.Finally,based on the lightning impulse withstand voltage,lightning trip-out rate and the cost of the protection schemes,the lightning protection schemes in different scenarios are proposed.The simulation results show that if the cost of the system is prioritised,the protection scheme of increasing the number of parallel stacks of the DL arresters can be selected,and if the power supply reliability of the system is prioritised,the protection scheme of installing the overhead ground wire as well as reducing grounding resistance can be selected. 展开更多
关键词 PSCAD/EMTDC LIGHTNING system
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