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Ligand-Enabled Ni-Catalyzed Enantioselective Hydroarylation of Styrenes and 1,3-Dienes with Arylboronic Acids

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CCS Chemistry 2019年第4期1卷 328-334页

作者： Xin-Yang Lv Chao Fan Li-jun Xiao jian-hua Xie Qi-Lin Zhou State Key Laboratory and Institute of Elemento-Organic Chemistry College of ChemistryNankai UniversityTianjin 300071China

We report an enantioselective hydroarylation reaction of styrenes and 1,3-dienes with arylboronic acids catalyzed by nickel complexes bearing chiral spiro amino phosphine *** reaction serves as an efficient,straightf orward,and mild method for the preparation of enantio enriched 1,1-diarylalkanes,which are important building blocks for the synthesis of many biologically active *** redox neutral reaction uses only catalytic amounts of the reagents and is,therefore,atom economical and environmentally benign.

关键词： nickel catalyst enantioselective hydroarylation alkene organoboron chiral spiro aminophosphine

Design of Variable Structure Control by Using the L_2 Gain Method

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International Journal of Plant Engineering and Management 2010年第2期15卷 97-102页

作者： GUO jian-guo ZHOU jun Institute of Precision Guidance and Control Northwestern Polytechnical University Xi'an 710072 P. R. China

The robust stabilization problem for a family of nonlinear plants with mismatch uncertainties is addressed, and a solution is presented based on variable structure control theory and H∞ control theory. A kind of boundary layer is built near the ideal switch surface which can eliminate chattering in the switch surface. The proposed control method with L2 gain can guarantee exponential stability of a system state with no parameter uncertainty and exter- nal disturbance, while it can guarantee state ultimate boundness if parameter uncertainty and external disturbance exist. In the proposed design method, stability of the closed-loop system is analyzed by adopting the Lyapurtov func- tion approach. Finally the numerical simulation results show that the proposed smooth variable structure controller has good pelformance without chattering in the switch surface.

关键词： variable structure control boundary layer Lyapunov methods stability, nonlinear system

Autophagic cell death induced by reactive oxygen species is involved in hyperthermic sensitization to ionizing radiation in human hepatocellular carcinoma cells

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World Journal of Gastroenterology 2017年第30期23卷 5530-5537页

作者： Guang-Jin Yuan jun-jian Deng De-Dong Cao Lei Shi Xin Chen Jin-Ju Lei Xi-Ming Xu Department of Oncology Nationality Hospital of Qianjiang Cancer Center Renmin Hospital of Wuhan University

AIM To investigate whether autophagic cell death is involved in hyperthermic sensitization to ionizing radiation in human hepatocellular carcinoma cells, and to explore the underlying *** human hepatocellular carcinoma cells were treated with hyperthermia and ionizing radiation. MTT and clonogenic assays were performed to determine cell survival. Cell autophagy was detected using acridine orange staining and flow cytometric analysis, and the expression of autophagy-associated proteins, LC3 and p62, was determined by Western blot analysis. Intracellular reactive oxygen species(ROS) were quantified using the fluorescent probe *** Treatment with hyperthermia and ionizing radiation significantly decreased cell viability and surviving fraction as compared with hyperthermia or ionizing radiation alone. Cell autophagy was significantly increased after ionizing radiation combined with hyperthermia treatment, as evidenced by increased formation of acidic vesicular organelles, increased expression of LC3 II and decreased expression of p62. Intracellular ROS were also increased after combined treatment with hyperthermia and ionizing radiation. Pretreatment with N-acetylcysteine, an ROS scavenger, markedly inhibited the cytotoxicity and cell autophagy induced by hyperthermia and ionizing *** Autophagic cell death is involved in hyperthermic sensitization of cancer cells to ionizing radiation, and its induction may be due to the increased intracellular ROS.

关键词： Autophagic cell death Hyperthermia Ionizing radiation Hepatocellular carcinoma Reactive oxygen species

A Confocal Technique Applicable to Studies of Cellular pH-related Signaling in Plants

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Journal of Integrative Plant Biology 2008年第6期50卷 682-690页

作者： Bing-Bing Lit Zhi-hui Gao Xiao-Yan Zhou hui-Bo Ren Min Xie Yi-Juan Fan jian-Fang hu Wen-Suo Jia College of Agronomy and Biotechnology China Agricultural University Beijing 100094 China

pH may act as a crucial signal in both animal and plant cells. It is very difficult to monitor pH signals and this has largely hindered progress in the investigation of pH signaling, particulady systematic pH signaling. Here, we report the development of a confocal technique to monitor leaf apoplastic pH in intact plants, which is particularly suitable for the studies on root to shoot signaling. A variety of different pH indicators and plant species were tested. It was found that different pH indicators, for example, 2＇,7＇-Bis-（2-carboxyethyl）-5-（and-6）-carboxyfluoresce （BCECF）, SNARF-4F 5-（and-6）- carboxylic acid （SNARF） and DM-NERF （NERF）, were of different properties, and to successfully monitor pH at a sub-cellular level, the comparability between the pH indicator and plant species must be involved according to their suitable pH range and loading characteristics. The loading characteristics of different pH indicators differ with different plant species, cell types and their developing stages. No matter what methods were adopted, BCECF and SNARF could not be loaded specifically in the leaf apoplast in sunflower, tomato, and Comelina communis L. In contrast, regardless of the methods adopted, NERF could be loaded efficiently and specifically in the leaf apoplast in C. communis, but not in other plants. In C. communis, the determination coefficient for in vitro and in situ calibration of NERF was very high, which was respectively 0.9951 and 0.991 6, and therefore, the adoption of NERF together with C. communis could construct an ideal experimental system that is suitable for the investigation of pH systematic signaling. Ratio image analysis demonstrated that the leaf apoplastic pH was about 5.5 in non-stressed conditions, and water deficit could trigger an increase in pH by about half a pH unit, which is the first evidence to directly indicate that pH is able to act as a systematic signal under water deficit conditions.

关键词： confocal microscope pH signaling water deficit.

Molecular Characteristics of Neisseria meningitidis Isolated during an Outbreak in a Jail: Association with the Spread and Distribution of ST-4821 Complex Serogroup C Clone in China

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Biomedical and Environmental Sciences 2013年第5期26卷 331-337页

作者： ZHANG Ji ZHOU Hai jian XU Li hu Guang Chun ZHANG Xue hua XU Sheng Ping LIU Zun Yu SHAO Zhu jun Jinan Municipal Center for Disease Control and Prevention State Key Laboratory for Infectious Disease Prevention and Control National Institute for Communicable Disease Control and PreventionChinese Center for Disease Control and Prevention

Objective To characterize the meningococcal strains isolated from cases and close contacts with meningococcal disease associated with an outbreak in a jail in May 2010 by investigating the national distribution of hyperinvasive ST-4821 serogroup C clone associated with this outbreak. Methods The cases were described based on the clinical symptoms and laboratory results. Pharyngeal swabs were cultured for N. meningitidis from men in the jail. Meningococcal isolates were identified by serogrouping, pulsed-field gel electrophoresis （PFGE） and multilocus sequence typing （MLST）, respectively. Four hundred and sixteen serogroup C N. meningitidis strains were collected from 27 provinces between 2003 and 2010 for a nationwide survey and analyzed by PFGE and MLST. Results Three persons in a jail system were infected with invasive N. meningitidis serogroup C. All isolates tested had matching PFGE patterns and belonged to the multilocus sequence type （ST） 4821 clonal complex. All 47 N. meningitidis strains were identified from the pharyngeal swabs of 166 peoples in the jail, and 26 of them belonged to ST-4821 serogroup C clone, and 90.14% （375/416） serogroup C strains identified in the nationwide survey belonged to the ST-4821 complex. The ST-4821 serogroup C clone was spread nationwide, distributed in 24 provinces, especially in eastern provinces between 2003 and 2010. Conclusion Endemic transmission and carriage rate of ST-4821 serogroup C clone are high in this jail system. The ST-4821 serogroup C clone is spreading in China and nationwide distributed despite the existence of some effective vaccines.

关键词： Pulsed-field gel electrophoresis Multilocus sequence typing Neisseria meningitidis ST-4821 Serogroup C

Study of dynamic pressure roadway supporting scheme under condi- tion of thick composite roof

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Journal of Coal Science & Engineering(China) 2013年第2期19卷 119-125页

作者： Wei-jun WANG Li-Qiang LUO Wei-jian YU Hai WU Yan-Si QU hunan Provincial Key Laboratory of Safe Mining Techniques of Coal Mines Hunan University of Science and TechnologyXiangtan 411201 China

This paper analyzed the strata behaviors of solid-coal roadway, gob-side entry driving and deformation law of surrounding rock in depth under high stress and thick composite roof based on the dynamic pressure roadway as engineering background in Fengcheng mining area, jiangxi province. The results, both field measurement and numerical simulation show that gob-side entry driving results the deformation of coal roadway main wall, however, entity-coal roadway driving results deformation of main roof and floor. The maintenance state of gob-side entry driving is better than entity-coal roadway, this situation is relevant to thick composite roof layered and easy collapse characteristics. At the same time, this paper put fox＇ward and proved proper dynamic pressure roadway supporting scheme under the surrounding rock condition and stress environment.

关键词： thick composite roof dynamic pressurized roadway high stress surrounding rock control

Abnormal resting-state functional network centrality in patients with high myopia： evidence from a voxel-wise degree centrality analysis

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International Journal of Ophthalmology(English edition) 2018年第11期11卷 1814-1820页

作者： Yu-Xiang hu jun-Rong He Bo Yang Xin huang Yu-Ping Li Fu-Qing Zhou Xiao-Xuan Xu Yu-Lin Zhong jun Wang Xiao-Rong Wu Department of Ophthalmology the First Affiliated Hospitalof Nanchang University Nanchang 330006 Jiangxi ProvinceChina Department of Quality Management Office the Affiliated Ganzhou Hospital of Nanchang University Ganzhou 341000Jiangxi Province China Department of Ophthalmology Xinjiang People's HospitalUrumqi 830000 Xinjiang Uygur Autonomous Region China Department of Ophthalmology Dongxiang People's HospitalFuzhou 344000 Jiangxi Province China Department of Radiology the First Affiliated Hospital of Nanchang University Jiangxi Province Medical Imaging Research Institute Nanchang 330006 Jiangxi Province China Second Department of Respiratory Disease Jiangxi Provincial People's Hospital Nanchang 330006 Jiangxi Province China

AIM： To investigate the functional networks underlying the brain-activity changes of patients with high myopia using the voxel-wise degree centrality（DC） ***： In total, 38 patients with high myopia（HM）（17 males and 21 females）, whose binocular refractive diopter were-6.00 to-7.00 D, and 38 healthy controls（17 males and 21 females）, closely matched in age, sex, and education levels, participated in the study. Spontaneous brain activities were evaluated using the voxel-wise DC method. The receiver operating characteristic curve was measured to distinguish patients with HM from healthy controls. Correlation analysis was used to explore the relationship between the observed mean DC values of the different brain areas and the behavioral ***： Compared with healthy controls, HM patients had significantly decreased DC values in the right inferior frontal gyrus/insula, right middle frontal gyrus, and right supramarginal/inferior parietal lobule（P〈0.05）. In contrast, HM patients had significantly increased DC values in the right cerebellum posterior lobe, left precentral gyrus/postcentral gyrus, and right middle cingulate gyrus（P〈0.05）. However, no relationship was found between the observed mean DC values of the different brain areas and the behavioral performance（P〉0.05）.CONCLUSION： HM is associated with abnormalities in many brain regions, which may indicate the neural mechanisms of HM. The altered DC values may be used as a useful biomarker for the brain activity changes in HM patients.

关键词： high myopia degree centrality functional magnetic resonance imaging resting state

Recent advances in network pharmacology applications in Chinese herbal medicine

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Traditional Medicine Research 2018年第6期3卷 260-272页

作者： jian Hao Shi-jun Li The Fourth Central Hospital Affiliated to Nankai University TianjinChina

Network pharmacology is a new discipline based on the theory of systems biology and network analysis of biological systems to design the *** comprehensively observes the intervention and influence of drugs on the disease network,and reveals the mystery of multi-molecular drugs synergistically acting on *** concepts reflect the ideas of multi-component,multi-target and system regulation,and have many similarities with the research ideas of traditional Chinese medicine,which focuses on syndrome differentiation and treatment,emphasizes the overall understanding of the etiology and *** pharmacology can be used to predict and identify the target and active component of traditional herbal medicine,to clarify the mechanism of action,to scientifically explain the rules of the prescription,to explore the rules of real-world prescription,to discover new indications and new active compounds,and to study drug relocation,*** applications of network pharmacology in traditional herbal medicine were systematically summarized to demonstrate the significant value in these areas.

关键词： Network pharmacology Applications Traditional herbal medicine Multi-molecular drugs Traditional Chinese medicine

风雨共同作用下大跨悬索桥加劲梁抖振响应分析

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中国铁道科学 2013年第6期34卷 30-35页

作者：胡俊欧进萍重庆交通大学土木建筑学院重庆400074 重庆交通大学山区桥梁与隧道工程国家重点实验室培育基地重庆400074 大连理工大学土木工程学院辽宁大连116024

基于降雨的基本特性,得到雨滴对桥梁断面的作用力,并将其分解为降雨冲击荷载和降雨阻尼力;结合形函数建立降雨的单元冲击荷载及单元阻尼矩阵,进而得到考虑降雨影响的大跨度悬索桥动力响应方程。以东海某大跨度悬索桥为对象进行风雨共同... 详细信息

基于降雨的基本特性,得到雨滴对桥梁断面的作用力,并将其分解为降雨冲击荷载和降雨阻尼力;结合形函数建立降雨的单元冲击荷载及单元阻尼矩阵,进而得到考虑降雨影响的大跨度悬索桥动力响应方程。以东海某大跨度悬索桥为对象进行风雨共同作用下大跨度悬索桥加劲梁抖振响应分析。结果表明,在大暴雨(强)作用下,主跨跨中的顺风向及竖向位移均值分别增大了16.24%和4.81%,说明在强风雨共同作用下雨滴对结构的顺风向冲击起主要作用;降雨产生的阻尼作用对结构响应有一定的积极影响,降雨的附加阻尼作用使主跨跨中的顺风向、竖向和扭转位移响应的均方差值分别降低了7.38%,2.28%和5.57%。

关键词：悬索桥大跨度加劲梁风雨作用抖振时程分析