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Analysis of Norditerpenoid Alkaloids Extracted from Aconitum sinomantanum Nakai by Electrospray Ionization Tandem Mass Spectrometry

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Chemical Research in Chinese Universities 2006年第3期22卷 343-346页

作者： XU Qing-xuan YUE Hao LIU Zhi-qiang wang Yong YAN cun-yu LIU Shu-ying Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun 130022 P. R. China

Electrospray ionization mass spectrometry（ESI-MS） was applied simultaneously in determining norditerpenoid alkaloids from the roots of Aconitum sinomantanum Nakai （RAS） based on molecular mass information. The tandem mass spectra（ ESI-MS^n） provided the alkaloidal structural information, through which the existence of these alkaloids was further confirmed. Accordingly, six known norditerpenoid alkaloids were simultaneously determined on the basis of their ESI-MS^n spectra. Furthermore, based on the diagnostic fragmentation pathways of alkaloidal MS^n, a rapid method for direct detection and characterization of alkaloids from an ethanolic extract of RAS was described.

关键词： Electrospray ionization tandem mass spectrometry( ESI-MS^n) Norditerpenoid alkaloid Aconitum sinomantanum Nakai

PEG-400 as an efficient reaction medium for the synthesis of 2,4,5-triaryl-1H-imidazoles and 1,2,4,5-tetraaryl-1H-imidazoles

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Chinese Chemical Letters 2009年第1期20卷 44-47页

作者： Xi cun wang Hai Peng Gong Zheng Jun Quan Lei Li He Lin Ye Gansu Key Laboratory of Polymer Materials College of Chemistry and Chemical Engineering Northwest Normal University Lanzhou 730070 PR China

An efficient protocol for the one-pot multicomponent synthesis of various 2,4,5 -triaryl- 1H-imidazoles and 1,2,4,5 -tetraaryl- 1H- imidazoles using PEG-400 as reaction medium is described. This method has the advanta... 详细信息

关键词： 2,4,5-Triaryl-1H-imidazoles 1,2,4,5-Tetraaryl-1H-imidazoles PEG-400 Benzil

Acoustic Absorption Characteristics of New Underwater Omnidirectional Absorber

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Chinese Physics Letters 2019年第4期36卷 43-46页

作者： cun wang Shan-De Li Wei-Guang Zheng Qi-Bai Huang State Key Laboratory of Digital Manufacturing Equipment and Technology School of Mechanical Science and Engineering Huazhong University of Science and Technology Hubei Institute of Specialty Vehicle School of Mechanical and Electrical Engineering Guilin University of Electronic Technology

We investigate a new underwater omnidirectional absorber with acoustic black hole effect to realize a broadband omnidirectional acoustic wave absorption. Based on multiple scattering theory, a two-dimensional axisymmetric model of underwater omnidirectional absorber comprised of an acoustic gradient refractive index structure and a hollow core is developed, and the mechanisms of omnidirectional absorption and dissipation of acoustic waves are studied. The numerical results indicate that the omnidirectional absorber developed here can achieve the omnidirectional absorption of incident acoustic waves in a broadband frequency and can effectively reduce the backscattering of acoustic waves. It potentially provides a new notion for underwater acoustic coating design.

关键词： underwater Absorber axisymmetric

Tonoplast-associated calcium signaling regulates manganese homeostasis in Arabidopsis

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Molecular Plant 2021年第5期14卷 805-819页

作者： Zhenqian Zhang Dali Fu Zhihui Sun Chuanfeng Ju Cuicui Miao Zhangqing wang Dixiang Xie Liang Ma Zhizhong Gong cun wang State Key Laboratory of Crop Stress Biology for Arid Areas and College of Life Sciences Northwest A&F UniversityYanglingShaanxi 712100People’s Republic of China State Key Laboratory of Plant Physiology and Biochemistry College of Biological SciencesChina Agricultural UniversityBeijing 100193China College of Life Sciences Hebei UniversityBaodingChina

Manganese(Mn)is an essential micronutrient in ***,excessive Mn absorption in acidic and waterlogged soils can lead to Mn *** their essential roles in Mn homeostasis,transcriptional and post-transcriptional modifications of Mn transporters remain poorly ***,we demonstrated that high-Mn stress induces an obvious Ca^(2+) signature in *** identified four calcium-dependent protein kinases,CPK4/5/6/11,that interact with the tonoplast-localized Mn and iron(Fe)transporter MTP8 in vitro and in *** cpk4/5/6/11 quadruple mutant displayed a dramatic high-Mn-sensitive phenotype similar to that of the mtp8 *** phosphorylated the N-terminal domain of MTP8 primarily at the Ser31 and Ser32 *** assays combined with multiple physiological experiments on phospho-dead variant MTP8^(S31/32A)and phospho-mimetic variant MTP8^(S31/32D)plants under different Mn and Fe conditions suggested that Ser31 and Ser32 are crucial for MTP8 *** addition,genetic analysis showed that CPKs functioned upstream of *** summary,we identified a tonoplast-associated calcium signaling cascade that orchestrates Mn homeostasis and links Mn toxicity,Ca^(2+) signaling,and Mn *** findings provide new insight into Mn homeostasis mechanisms and Ca^(2+) signaling pathways in plants,providing potential targets for engineering heavy metal toxicity-tolerant plants.

关键词： manganese calcium calcium-dependent protein kinases MTP8 iron

“Fast Track”nasogastric decompression of rectal cancer surgery

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Frontiers of Medicine 2011年第3期5卷 306-309页

作者： Ka Li Zongguang Zhou Zengrong Chen Yi Zhang cun wang Department of Gastrointestinal Surgery West China HospitalSichuan UniversityChengdu 610041China Institute of Digestive Surgery West China HospitalSichuan UniversityChengdu 610041China

This study evaluates the application of fast track(FT)nasogastric decompression in patients who underwent anterior resection of rectal cancer.A randomized control trial was performed comparing the group with the fast track treatment(n=57)and the group with traditional nasogastric decompression(n=84).Preoperative characteristics and postoperative recovery indices were recorded and *** results indicate no significant differences in gender(P=0.614),age(P=0.653),tumor location(P=0.113),and TNM stages(P=0.054)were observed between the 2 *** differences in the type of resection,anastomosis,and adoption of protective colostomy were all not significant between the FT and the traditional *** the first 24 hours after surgery,the volume of nasogastric drainage averaged 197 ml in the FT group and 155 ml in the traditional group(P=0.197).The initiation of test-meal(P=0.000),semiliquid diet(P=0.002),and ordinary diet(P=0.008)were all significantly shorter in the FT ***,compared with the other group,the patients in the FT group enjoyed earlier removal of the abdominal drainage,urinary catheter,and shorter hospital stays(P=0.000).Based on a correlation test,the duration of nasogastric decompression is related to the time of test-meal and semiliquid *** routine usage of nasogastric decompression in rectal surgery is *** fast track procedure might help in facilitating postoperative functional and diet recovery,reducing the time of catheterization,and shortening hospital stay.

关键词： fast track nasogastric decompression rectal cancer surgery

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冷轧板边部表面色差缺陷原因分析及改进措施

鞍钢技术 2024年第1期 68-72页

作者：何士国李江委王存王杰刘旺臣宋运涛鞍钢股份有限公司鲅鱼圈钢铁分公司辽宁营口115007

针对生产st13镀锌用冷轧板边部表面色差缺陷问题,对热轧板和酸洗板表面粗糙度进行了检测分析,结果表明,热轧板边部与中间部位的表面粗糙度差异大是边部表面产生色差的主要原因。结合热轧板横断面的铁皮厚度,分析了钢板表面粗糙度差异大... 详细信息

针对生产st13镀锌用冷轧板边部表面色差缺陷问题,对热轧板和酸洗板表面粗糙度进行了检测分析,结果表明,热轧板边部与中间部位的表面粗糙度差异大是边部表面产生色差的主要原因。结合热轧板横断面的铁皮厚度,分析了钢板表面粗糙度差异大的原因。根据实际生产情况,调整冷轧末机架轧机负荷和优化板形,改善钢板表面的色差缺陷,通过合理匹配热轧卷取温度和层流冷却模式,解决了st13钢板表面的边部色差问题。

关键词：层流冷却卷取温度表面色差粗糙度

基于切比雪夫多项式展开的转子动力特性区间分析

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航空动力学报 2020年第4期35卷 757-765页

作者：王存中国航天科工集团有限公司北京动力机械研究所激光推进及其应用国家重点实验室北京100074

基于切比雪夫多项式展开,建立了转子系统临界转速和稳态响应区间分析方法,能在仅具有参数上下界的情况下获得结果分布区间。针对临界转速区间分析问题,将支承刚度、密度和弹性模量视为区间变量,建立转子系统固有频率的切比雪夫多项式表... 详细信息

基于切比雪夫多项式展开,建立了转子系统临界转速和稳态响应区间分析方法,能在仅具有参数上下界的情况下获得结果分布区间。针对临界转速区间分析问题,将支承刚度、密度和弹性模量视为区间变量,建立转子系统固有频率的切比雪夫多项式表达式,最终获得临界转速区间,临界转速误差不超过0.07%。在固有特性分析基础上,应用切比雪夫方法求解转子系统的稳态响应,并由模态叠加原理对响应区间进行修正,解决了固有特性不确定性较大时稳态响应求解精度不足的问题。与蒙特卡洛插值结果相比,响应上界误差不超过8%。基于切比雪夫展开的非确定分析方法,不需修改原结构的振动微分方程。结果表明该方法结合商业有限元软件后,应用简单,并具有理想的精度。

关键词：不确定性区间分析转子动力特性临界转速切比雪夫多项式

Inhibition of CK2 Activity by TCDD via Binding to ATP-competitive Binding Site of Catalytic Subunit： Insight from Computational Studies

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Chemical Research in Chinese Universities 2013年第2期29卷 299-306页

作者： XU Xian-jin CANNISTRARO Salvatore BIZZARRI Anna-rita ZENG Yi CHEN Wei-zu wang cun-xin College of Life Science and Bioengineering Beijing University of Technology Beijing 100124 P. R. China Biophysics and Nanoscience Centre CNISM Dipartimento di Biologia ed Ecologia(DEB) Universita della Tuscia Viterbo 01100 Italy

Alternative mechanisms of toxic effects induced by 2,3,7,8-tetrachlorodibenzo-p-dioxin（TCDD）, instead of the binding to aryl hydrocarbon receptor（AhR）, have been taken into consideration. It has been recently shown that TCDD reduces rapidly the activity of CK2（casein kinase II） both in vivo and in vitro. It is found that TCDD has high molecular similarities to the known inhibitors of CK2 catalytic subunit（CK2a）. This suggests that TCDD could also be an ATP-competitive inhibitor of CK2a. In this work, docking TCDD to CK2 was carried out based on the two structures of CK2a from maize and human, respectively. The binding free energies of the predicted CK2a-TCDD complexes estimated by the molecular mechanics/Poisson-Boltzmann surface area（MM/PBSA） method are from -85.1 kJ/mol to -114.3 kJ/mol for maize and are from -96.1 kJ/mol to -118.2 kJ/mol for human, which are comparable to those estimated for the known inhibitor and also ATP with CK2a. The energetic analysis also reveals that the van der Waals interaction is the dominant contribution to the binding free energy. These results are also useful for designing new drugs for a target of overexpressing CK2 in cancers.

关键词： Casein kinase II Dioxin Inhibitor Modeling Binding free energy

Synthesis and Biological Activities of Quinoline Derivatives as HIV-1 Integrase Inhibitors

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Chemical Research in Chinese Universities 2009年第6期25卷 841-845页

作者： LUO Zai-gang ZENG Cheng-chu wang Fang HE Hong-qiu wang cun-xin DUHong-guang HU Li-ming College of Life Science and Bioengineering Beijing University of Technology Beijing 100124 P. R. China College of Science Beijing University of Chemical Technology Beijing 100029 P. R. China

Based on the structure of the integrase core domain and pharmacophore perception, the authors picked out the hit quinolone derivative 1 as the lead compound via virtual screen in ACD, MDDIL NCI and Chinese Herb three-dimensional database with the aid of DOCK4.0 program and synthesized a series of analogues of compound 1. Their primary anti-HIV properties against integrase reveal that 6-position methyl group on the benzene ring of quinolone plays a more important role than chlorine, 7-position methyl group or no substituted group. But the title compounds exhibit little difference When the substituted group was phenyl or thienyl on the pyridine ring of quinoline.

关键词： Quinolone Integrase Anti-HIV activity