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Synthesis of (±)-Demethylnitidanin, Herpetol and Salvinal as well as Their Glycosyl Derivatives

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Chemical Research in Chinese Universities 2011年第6期27卷 949-954页

作者： WU Zheng liANG zhi-ying li wei REN Ying-mei WANG Qiu-an State Key Laboratory of Chemo/Biosensing and Chemometrics College of Chemistry and Chemical Engineering Hunan University Changsha 410082 P. R. China

Three neolignans, （±）-demethylnitidanin（1）, herpetol（2） and salvinal（3） were synthesized from methyl 4,5-dihydroxy-3-methoxy cinnamate or methyl 4-hydroxy-3-methoxy cinnamate with Ag2O-catalyzed biomimetic oxidative coupling as the key step of the synthetic route. Five novel benzofuran neolignan-4＇-O-β-D-glycosides（4―8） were achieved by the glycosylation reactions of benzofuran neolignans 2, 3 and 15. The structures of all the compounds synthesized were determined by MS, 1H NMR and IR spectra. （±）-Demethylnitidanin（1） and herpetol（2） were the first synthesized and the synthesis of salvinal（3） was efficiently improved by the new synthetic routes.

关键词： Neolignan (±)-Demethylnitidanin Herpetol Salvinal Glycosylation

Direct Climatic Effect of Aerosols and Interdecadal Variations over East Asia Investigated by a Regional Coupled Climate-Chemistry/Aerosol Model

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Atmospheric and Oceanic Science Letters 2011年第6期4卷 299-303页

作者： HAN zhi-wei XIONG Zhe li Jia-wei Key Laboratory of Regional Climate-Environment Research for Temperate East Asia （RCE-TEA） Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China

The direct climatic effect of aerosols for the 1980-2000 period over East Asia was numerically investigated by a regional scale coupled climate-chemistry/ aerosol model, which includes major anthropogenic aerosols （sulfate, black carbon, and organic carbon） and natural aerosols （soil dust and sea salt）. Anthropogenic emissions used in model simulation are from a global emission inventory prepared for the Intergovernmental Panel on Climate Change Fifth Assessment Report （IPCC AR5）, whereas natural aerosols are calculated online in the model. The simulated 20-year average direct solar radiative effect due to aerosols at the surface was estimated to be in a range of-9- -33 W m-2 over most areas of China, with maxima over the Gobi desert of West China, and-12 W m-2 to -24 W m-2 over the Sichuan Basin, the middle and lower reaches of the Yellow River and the Yangtze River. Aerosols caused surface cooling in most areas of East Asia, with maxima of-0.8℃ to -1.6℃ over the deserts of West China, the Sichuan Basin, portions of central China, and the middle reaches of the Yangtze River. Aerosols induced a precipitation decrease over almost the entire East China, with maxima of-90 mm/year to -150 mm/year over the Sichuan Basin, the middle reaches of the Yangtze River and the lower reaches of the Yellow River. Interdecadal variation of the climate response to the aerosol direct radiative effect is evident, indicating larger decrease in surface air temperature and stronger per- turbation to precipitation in the 1990s than that in the 1980s, which could be due to the interdecadal variation of anthropogenic emissions.

关键词： aerosols direct radiative effect climatic response interdecadal variation model simulation

Chronic hepatitis virus infection increases the risk of pancreatic cancer: a meta-analysis

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Hepatobiliary & Pancreatic Diseases International 2013年第6期12卷 575-583页

作者： Shuai Xing zhi-wei li Yuan-Feng Tian li-Min Zhang Ming-Qiang li Ping Zhou Institute of Organ Transplantation Tongji Hospital Tongji Medical CollegeHuazhong University of Science and Technology Key Laboratory of Organ Transplantation Ministry of Health and KeyLaboratory of Organ TransplantationMinistry of Education Department of Radiology Tongji Hospital Tongji Medical CollegeHuazhong University of Science and Technology Department of Urology Tongji Hospital Tongji Medical CollegeHuazhong University of Science and Technology

BACKGROUND:Several reports have inconsistently demonstrated that there is an association between hepatitis B virus(HBV)or hepatitis C virus(HCV)infections and pancreatic cancer(PC).The aim of the present meta-analysis is to assess this possible *** SOURCES:Studies were identified by searching available database from January 2000 to July *** associations between PC risk and hepatitis B surface antigen(HBsAg)and its antibody(HBsAb),hepatitis B e antigen(HBeAg)and its antibody(HBeAb),anti-HBcAg antibody(HBcAb),and HCV antibody(anti-HCV)were ***:Eight case-control and two cohort studies were included,and their quality scores were assessed by the modified Newcastle-Ottawa Quality Assessment Scale(NOS).We found that HBsAg and anti-HCV seropositivity significantly increased risk of PC(OR=1.28,95%CI:1.11-1.48 and OR=1.21,95%CI:1.02-1.44).The presence of HBsAb was associated with a statistically significant decrease in the risk of PC(OR=0.40,95%CI:0.20-0.79)and HBeAb(OR=0.62,95%CI:0.39-0.99).HBsAg–/HBcAb+/HBsAb–or HBsAg–/HBcAb+/HBsAb+profile was not related to PC risk(OR=1.57,95%CI:0.83-2.98 and OR=1.24,95%CI:0.72-2.14).CONCLUSIONS:HBV/HCV infection increases the risk of *** and HBeAb seropositivity may be the protective factors against *** is still uncertain whether serological pattern of past exposure to HBV with or without natural immunity is associated with an enhanced probability of this malignancy.

关键词： hepatitis B virus hepatitis C virus HBV status pancreatic cancer meta-analysis

A direct coupling analysis method of hydroelastic responses of VLFS in complicated ocean geographical environment

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Journal of Hydrodynamics 2019年第3期31卷 582-593页

作者： Jun Ding You-sheng Wu Ye Zhou zhi-wei li Chao Tian Xue-feng Wang Zheng-wei Zhang Xiao-long liu China Ship Scientific Research Center Wuxi 214082 China School of Naval Architecture Ocean and Civil Engineering Shanghai Jiao Tong University Shanghai 200240 China

In this paper a direct coupling analysis method (DCAM) of hydroelastic responses of a very large floating structures (VLFS) in complicated geographical environment is presented. In this method the three-dimensional hydroelasticity theory of floating bodies is combined with the shallow water wave theory, to allow for proper description of the influence of uneven seabed and sheltering effect of islands on the hydroelastic responses of a VLFS deployed near island and reefs in shallow sea. This method and the numerical procedures were verified and validated by comparison-between the predictions and the model test results of a 3-module VLFS and an 8-module VLFS in two simulated shallow sea regions with different seabed topography.

关键词： Direct coupling analysis method very large floating structure (VLFS) hydroeiasticity complicated environment

Prevalence and characteristics of ophthalmological extra-intestinal manifestations in Chinese patients with inflammatory bowel disease

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International Journal of Ophthalmology(English edition) 2016年第10期9卷 1476-1479页

作者： Ying-Chao li wei-zhi li Chang-Rui Wu Yun Feng li Ren Chen Mi Yang li Department of Gastroenterology the First Affiliated Hospital of Xi'an Jiaotong University Department of Ophthalmology the First Affiliated Hospital of Xi'an Jiaotong University Department of Otolaryngology-Head and Neck Surgery the Second Affiliated Hospital of Xi'an Jiaotong University

AIM：To investigate the prevalence of ophthalmological extra-intestinal manifestations（O-EIMs） in Chinese patients with inflammatory bowel disease（IBD） and to identify risk factors for the development of ***：The study population consisted of Chinese patients with a definite diagnosis of Crohn＇s disease（CD） or ulcerative colitis（UC） in a large teaching hospital between January 1995 and December *** and clinical characteristics of patients were extracted ***： In this twenty-year cohort,645 IBD patients（517 with UC,128 with CD） were *** them122（18.9%） exhibited at least one *** 13 patients（2.0%） developed O-EIMs,7 of CD（5.5%） and 6 of UC（1.2%）.Clinical ophthalmological manifestations included redness（76.9%）,burning（61.5%）,pain（38.5%）,itching（15.4%） of eyes and vision change（7.7%）.O-EIMs included episcleritis（7）,uveitis（5） and dry eye（1）.OEIMs were more prevalent in female（odds ratio for male0.61,95% confidence interval 0.52-0.73,P 〈0.0001）,and patients who had IBD diagnosis at young age（odds ratio for patients aged 〉30 years 0.76,95% confidence interval0.65-0.88,P 〈0.0001）.CONCLUSION： The frequency of O-EIMs in Chinese patients with IBD is lower than the rates reported in the studies of European and American *** uveitis are the most common O-EIMs.O-EIMs are more frequent in patients with CD and more prevalent in female and patients who have IBD diagnosis at young age.

关键词： ophthalmological extraintestinal manifestations inflammatory bowel disease episcleritis uveitis

Crack analysis in Ti-6Al-4V alloy produced by selective laser melting

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Tungsten 2021年第3期3卷 361-367页

作者： Hui-Yan Zhang Yan-Hui liu zhi-wei li An-Hui Xiong Ke li Jia-Yun Fu School of Materials Engineering Shanghai University of Engineering ScienceShanghai 201620China

Quality and property control have become one of the critical problems for the metallic parts produced by selective laser *** this paper,the crack spontaneously formed in the Ti-6 Al-4 V alloy by selecting laser melting is *** crack is C-shape without branching in macro *** micro view,the crack originates from and propagates toward the selective laser melting(SLM)processing *** crack surface topography shows that the crack is typical dimple cleavage.A few heads of martensiticα’laths appear at the bottom of the *** the secondary crack nucleates and grows up near by the martensiticα’laths.A lot of spatters and cavities formed at the top surface of the SLM body and the residual stress accumulated in the SLM body is up to 640 MPa,which confirms that the SLM processing defects and the residual stress induced the origination and propagation of the *** research results indicate that preventing spatter and controlling residual stress are important to SLM processing.

关键词： Selecting laser melting Ti-6Al-4V Crack Processing defect Residual stress

Evaluation of corneal endothelium after UVA/riboflavin cross-linking in thin keratoconic corneas

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International Journal of Ophthalmology(English edition) 2016年第2期9卷 321-322页

作者： wei Chen zhi-wei li Xiao-Min Zhao Wen -Wen Xu Guo-Ying Mu Clinical College of Ophthalmology Tianjin Medical University Department of Ophthalmology Shandong Provincial Hospital Affiliated to Shandong University School of Nursing Binzhou Medical College

Dear Sir,UVA/riboflavin cross-linking （CXL） has been used clinically applied for the treatment of keratoconus and corneal edema via enhancement of corneal stiffness The safety of the corneal endothelium is of prime importance during CXL treatment. In clinical practice, a corneal thickness （CT） of 400um has traditionally been regarded as the minimum treatable thickness, thereby avoiding damage to the corneal endothelium Although CXL has been applied to thinner corneas, using a hypoosmotic solution onto cornea and inducing edema . CXL safety still needs further evaluation because of lower relative concentration of collagen in the hydrated stroma . This study aims to evaluate the changes of corneal endothelial density （ECD） in cases where the CT is 〈400 um before iatrogenic corneal swelling and CXL treatment.

关键词： UVA Evaluation of corneal endothelium after UVA/riboflavin cross-linking in thin keratoconic corneas

Recent advances and perspectives on prelithiation strategies for lithium-ion capacitors

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Rare Metals 2022年第10期41卷 3322-3335页

作者： Jiang-Min Jiang zhi-wei li Zhao-Ting Zhang Shi-Jing Wang Hai Xu Xin-Ran Zheng Ya-Xin Chen zhi-Cheng Ju Hui Dou Xiao-Gang Zhang Jiangsu Key Laboratory of Electrochemical Energy Storage Technology College of Material Science and EngineeringNanjing University of Aeronautics and AstronauticsNanjing210016China Jiangsu Key Laboratory of Coal-Based Greenhouse Gas Control and Utilization School of Materials Science and PhysicsChina University of Mining and TechnologyXuzhou221116China Department of Physics National University of SingaporeSingapore117574Singapore Tsinghua Shenzhen International Graduate School Tsinghua UniversityShenzhen518055China

lithium-ion capacitors(liCs),consisting of a capacitor-type material and a battery-type material together with organic electrolytes,are the state-of-the-art electrochemical energy storage devices compared with supercapacitors and *** to their unique characteristics,liCs received a lot of attentions,and great progresses have been achieved,especially in the exploration of cathode and anode *** techniques are regarded as indispensable procedures for liCs systems,which can compensate for the initial irreversible capacity loss,increase the li^(+)concentration in the electrolyte,raise the working voltage and resolve the safety and cycle stability issues;however,its research progress is slow,and there is not enough attention until *** this overview,we look into the ongoing processes on the recent development of prelithiation technologies,especially in organic electrolyte consumption-type *** particular,some prelithiation strategies for liCs are summarized and discussed in detail,including the ex situ electrochemical method,in situ electrochemical method,and cathode prelithiation additives ***,we propose some unresolved challenges and prospects for prelithiation technologies from the basic research ideas and future key research *** work aims to bring up new insights to reassess the significance of premetallation strategies for advanced hybrid-ion capacitors based on the currently proposed prelithiation strategies.

关键词： lithium-ion capacitors(liCs) Prelithiation Initial irreversible capacity Stabilized lithium metal powder Self-sacrificial additives

Recognition of Protein Native Folds Using a Continuous Potential Function

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Chemical Research in Chinese Universities 1994年第2期10卷 134-140页

作者： WANG Yu-hong, LU zhi-bin and li wei(Department of Molecular Biology , Jilin University , Changchun, 130023 )

e report a simple continuous potential function that can recognize proteinchains' native folds from tens of thousands of alternative ones. Empirical parame-ters for this potential function were obtained by a neural network learning oversamples generated from PDB structural *** interactions were foundto be mainly responsible for stabilization of the protein' s native fold. The inter-chain interaction was found indispensable in stabilizing some protein chains' nativeconformation.

关键词： Recognition Protein native fold Function