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BrΦnsted acid-promoted ‘on-water’ C(sp^3)-H functionalization fot the synthesis of isoindolinone/[1,2,4]triazolo[1,5-a]pyrimidine derivatives targeting the SKP2-CKS1 interaction

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Chinese Chemical Letters 2020年第2期31卷 349-352页

作者： Shuo Yuan Sixi Wang Min Zhao danqing Zhang Jinjie Chen Jian-Xin Li Jingya Zhang Yihui Song Jinyi Wang Bin Yu Hongmin Liu School of Pharmaceutical Sciences Zhengzhou UniversityZhengzhou 450001China

The isoindolinone and biaryl scaffolds are prevalent in natural products and drug molecules,which have showed broad and interesting biological *** efficient construction of such hybridized molecules and biological evaluation are of great interest to medicinal chemistry *** this communication,we report an efficient BrΦnsted acid-promoted C(sp^3)-H functionalization approach that enables the rapid construction of biologically important isoindolinone/[1,2,4]triazolo[1,5-a]pyrimidine hybrids from 5-methyl-7-(2,4,6-trimethoxyphenyl)-[1,2,4]triazolo[1,5-a]pyrimidine,2-formylbenzoic acid and various *** title compounds were generated in high to excellent yields(up to 96%)regardless of the electronic nature and steric effects of the *** this reaction,an isoindolinone scaffold,one C-C single bond,and two C-N bonds were formed simultaneously with high atom *** this work,we have envisioned that the methyl group linked to the electron-deficient Nheterocycles could be used as a new synthetic handle for late-state diversification and may have broad applications in the field of organic and medicinal ***,the title compounds have exhibited promising activity against the SKP2-CKS1 interaction.

关键词： Isoindolinone Triazolo[1,5-a]pyrimidine Biaryl scaffold C(sp^3)-H activation Molecular hybridization SKP2-CKS1 interaction

Trophic relationships in the Changjiang River estuarine salt marshes: preliminary investigation from δ^(13)C and δ^(15)N analysis

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Acta Oceanologica Sinica 2009年第3期28卷 50-58页

作者： QUAN Weimin HUANG danqing CHU Tianjiang SHENG Qiang FU Cuizhang CHEN Jiakuan WU Jihua Coastal Ecosystems Research Station of Yangtze River Estuary Ministry of EducationKey Laboratory for Biodiversity Science and Ecological Engineering Fudan UniversityShanghai 200433 China

To obtain information on food web structure in salt marshes of the Changjiang （Yangtze） River Estuary, the （ δ3C and δ15N values of primary producers and consumers were determined. The mean δ13C values of 31 dominant consumers ranged from -23.13‰ to -14.37‰. Except for several species （ Eriocheir sinensis, Sinonovacula constricta and Potamocorbula ustulata）, consumers had interme- diate δ13C values between those of benthic microalgae and Spartina alterniflora. The mean δ15N values of 31 dominant consumers varied between 6.87‰ and 13.33‰, which indicate three trophic levels in salt marshes of the Changjiang River Estuary. A total of 18 macroinvertebrates species and four fish species represented primary consumers with trophic levels ranging from 2.0 to 2.7. Secondary consumers included two maeroinvertebrates and seven fishes with trophic levels varying between 3.0 and 3.9. The consumers were divided into three trophic guilds, i.e., detritivorous/algae feeders, omnivores and carnivores. The detrital food chain was the main energy flow pathway in the salt marsh food web of the Changjiang River Estuary, and the marsh vascular plants were at least as equally important as microphytobenthos for secondary production. The important trophic function of the salt marsh habitats in the estuary is revealed.

关键词： energy base food web salt marshes stable isotope trophic level Changjiang River Estuary

从博弈关系探讨城市更新中的政府行为——以居住区为例

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城市发展研究 2023年第8期30卷 76-82+99页

作者：薛丹青南开大学经济学院

从不同的城市更新模式来看，市场与政府都发挥着很大的作用，以政府与市场关系为切入点将城市更新模式分为：自上而下的政府主导模式；放权自治下的政府推动，市场主导模式；政府统筹整合下市场发挥重要作用的模式。在对不同模式的城市... 详细信息

从不同的城市更新模式来看，市场与政府都发挥着很大的作用，以政府与市场关系为切入点将城市更新模式分为：自上而下的政府主导模式；放权自治下的政府推动，市场主导模式；政府统筹整合下市场发挥重要作用的模式。在对不同模式的城市更新现实困境进行梳理总结后构建博弈模型，从社会总福利与自身利益最大化两个角度分析政府与市场行为，明晰城市更新中的政府职责。

关键词：城市更新政府职能政府与市场边界多元博弈

Construction of mini-Tn4001 transposon vector for Mycoplasma gallisepticum

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Science China(Life Sciences) 2010年第11期53卷 1340-1345页

作者： CHEN HongJun, ZHAO ChunMei, SHEN XieYue, CHEN danqing, YU ShengQing & DING Chan Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, China Shanghai Veterinary Research Institute Chinese Academy of Agricultural Sciences Shanghai China

The detailed genetic analysis of mycoplasmas has long been hampered by the lack of appropriate tools for genetic manipulation. In this study, the transposon vector, mini-Tn4001tetM, was constructed containing the tnp gene, encoding a transposase gene in Staphylococcus aureus, two copies of the IS256 inverted repeat sequence (inner and outer) and the tetM gene, from the Enterococcus faecalis Tn916 transposon, conferring resistance to tetracycline. This vector was electro-transformed into Mycoplasma gallisepticum (MG). The recombinant cells were screened by tetracycline selection. The results indicated that the transposon vector could replicate in MG strain R by successive passages, indicating that MG is a potential vector for expressing protective antigens of other pathogens.

关键词： Mycoplasma gallisepticum mini-Tn4001 transposon vector mycoplasma transformation

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低能X射线工业CT小间隔信号采集系统

强激光与粒子束 2013年第1期25卷 114-118页

作者：周钦高富强陈聃青陈晟飞重庆大学自动化学院重庆400030 重庆大学光电技术及系统教育部重点实验室 ICT研究中心重庆400030 大唐移动通信设备有限公司北京100083

为克服探测器阵列获取速度慢、重建图像精度低的缺点,并能在低能X射线的小焦点/微焦点CT系统中完成对小型精密复杂器件的检测,研究了低能X射线工业CT的小间隔信号采集系统。系统选取DT公司0.2mm像素尺寸、高集成度、扫描速度快的X-CARD ... 详细信息

为克服探测器阵列获取速度慢、重建图像精度低的缺点,并能在低能X射线的小焦点/微焦点CT系统中完成对小型精密复杂器件的检测,研究了低能X射线工业CT的小间隔信号采集系统。系统选取DT公司0.2mm像素尺寸、高集成度、扫描速度快的X-CARD 0.2-256G为探测器,Altera公司的CycloneEP1C3T为主控芯片,Intel公司的LXT972A为以太网控制芯片。从数据传输的可靠、稳定、高效率角度出发,用模块化的方法给出了系统的硬件设计,用有限状态机技术完成了系统的逻辑单元设计,并对系统的动态范围进行了测试。测试实验结果表明,系统的动态范围大于4000,能够检测精密器件、准确迅速地完成信号的采集传输,满足实际工业CT对信号采集的要求。

关键词：低能X射线工业CT 小间隔现场可编程门阵列信号采集系统

利用GEK代理模型的天线快速多目标优化设计

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西安电子科技大学学报 2018年第2期45卷 129-134,165页

作者：王丹青李萍武警工程大学信息工程系陕西西安710086

传统方法进行天线优化设计主要利用经典优化算法调用电磁仿真软件,在求解复杂天线的多目标优化问题时效率不理想.针对该问题,在多梯度下降算法中引入遗传算子,提出了一种高效的全局多目标优化算法——混合遗传算子多梯度下降算法.该算... 详细信息

传统方法进行天线优化设计主要利用经典优化算法调用电磁仿真软件,在求解复杂天线的多目标优化问题时效率不理想.针对该问题,在多梯度下降算法中引入遗传算子,提出了一种高效的全局多目标优化算法——混合遗传算子多梯度下降算法.该算法调用梯度增强型克里金模型进行天线优化.梯度增强型克里金模型建模所需的样本规模小、时间短,并且避免了电磁仿真软件的反复计算.利用该算法优化加载各向异性Ⅰ型周期结构覆层的警用超短波宽带单极子天线和某型直升机机载专用通信系统天线及其抗干扰阵列,在达到相同优化效果时,所需的模型仿真次数为利用改进的非支配排序遗传算法调用电磁仿真软件进行优化的10.30%和18.96%,验证了该优化算法的高效性.

关键词：天线多目标优化多梯度下降算法遗传算子代理模型梯度增强型克里金模型

Discovery and development of tricyclic matrinic derivatives as anti-diabetic candidates by AMPKαactivation

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Chinese Chemical Letters 2023年第1期34卷 289-294页

作者： Yinghong Li Yuanhui Zhang Tianyu Niu Yudong Pang Yulong Shi Qingxuan Zeng Jingpu Zhang Jingyang Zhu Xiuli Zhong Yanxiang Wang Yan Wang Sheng Tang Weijia Kong danqing Song Jiandong Jiang Institute of Medicinal Biotechnology Chinese Academy of Medical Sciences&Peking Union Medical CollegeBeijing 100050China

We found compound 12N-p-trifluoromethylbenzenesulfonyl matrinane(1)was a potent anti-diabetic ***-five tricyclic matrinic derivatives were synthesized and determined for their stimulatory effects on glucose consumption in L6 myotubes,taking 1 as the *** high-fat diet(HFD)and STZ induced diabetic mice,9a significantly lowers blood glucose,improves glucose tolerance,and especially alleviates diabetic nephropathy and islet *** study indicates that 9a simultaneously targets mitochondrial complex I to increase AMP/ATP ratio,as well as liver kinase B1(LKB1)and calcium/calmodulindependent protein kinase(Ca MKK),which synergistically activates AMPKαand then stimulates glucose transporter 4(GLUT4)membrane translocation and 2-deoxyglucose(2-DG)uptake to exert anti-diabetic ***,compound 9a with a novel structure is a promising anti-diabetic candidate with the advantage of multiple-target mechanism,worthy of further investigation.

关键词： Tricyclic matrinic derivatives Glucose consumption Diabetes mellitus AMP-activated protein kinase(AMPK)

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热障涂层陶瓷材料的研究现状及发展趋势

材料导报 2007年第1期21卷 1-3,17页

作者：周宏明易丹青周楠长沙中南大学材料科学与工程学院 410083

热障涂层陶瓷材料的研究是开发适用于下一代高性能航空涡轮发动机热障涂层体系的关键,也是未来热障涂层技术发展的重要方向之一。可用作热障涂层陶瓷材料的主要有用Al_2O_3、Y_2O_3等稳定剂稳定的ZrO_2、稀土锆酸盐和一些具有钙钛矿结... 详细信息

热障涂层陶瓷材料的研究是开发适用于下一代高性能航空涡轮发动机热障涂层体系的关键,也是未来热障涂层技术发展的重要方向之一。可用作热障涂层陶瓷材料的主要有用Al_2O_3、Y_2O_3等稳定剂稳定的ZrO_2、稀土锆酸盐和一些具有钙钛矿结构的氧化物(石榴石、独居石以及LaMgAl11O19等),综述了上述热障涂层陶瓷材料的热物性能和力学性能,对其研究现状及发展趋势进行了分析和探讨。

关键词：热障涂层陶瓷材料研究现状发展趋势

广州白云机场“721”低空风切变天气过程综合分析

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北京大学学报（自然科学版） 2007年第1期43卷 23-29页

作者：刘峰刘式达文丹青北京大学物理学院大气科学系民航中南空中交通管理局气象中心广州510406

对2005年7月21日发生在广州白云机场的一次低空风切变飞行事件进行分析,发现此次过程是由超级单体风暴云产生的下击暴流和阵风锋造成的。利用机场实时的多普勒气象雷达和地面自动观测资料定量计算出风切变的大小,从而确定风切变和飞机... 详细信息

对2005年7月21日发生在广州白云机场的一次低空风切变飞行事件进行分析,发现此次过程是由超级单体风暴云产生的下击暴流和阵风锋造成的。利用机场实时的多普勒气象雷达和地面自动观测资料定量计算出风切变的大小,从而确定风切变和飞机颠簸的强度等级。并通过与飞行数据作检验分析,证实在广州白云机场现有的条件下,设计出的风切变预警方法是基本可行的。

关键词：低空风切变飞机颠簸下击暴流阵风锋