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Synthesis and Unexpected Ring-opening Reaction of a New TADDOL Analogue with Chiral Cyclopropane Ring as Backbone

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Chinese Chemical Letters 2006年第5期17卷 606-608页

作者： Jun LIU Qing hua BIAN ming An wang Hong Chao GUO Min wang Department of Applied Chemistry China Agricultural University Beijing 100094

Synthesis and ring-opening reaction of TADDOL analogue with cyclopropane as chiral backbone were described. A plausible ring-opening and carbonium ion rearrangement mechanism have been proposed.

关键词： TADDOL analogue ring-opening cyclopropane ring synthesis. tetraaryl-1 3-dioxolane-4 5-dimethanol

Evaluation of live attenuated S79 mumps vaccine effectiveness in mumps outbreaks： a matched case-control study

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Chinese Medical Journal 2009年第3期122卷 307-310页

作者： FU Chuan-xi NIE Jun LIANG Jian-hua wang ming Guangzhou Center of Disease Control and Prevention GuangzhouGuangdong 510080 China

Background Mumps virus infection is a potentially serious viral infection of childhood and early adulthood. In China, live attenuated S79 mumps vaccine has been licensed for pediatric use since 1990. The objective of this study was to determine the effectiveness of live attenuated S79 mumps vaccine against clinical mumps in outbreaks. Methods Cases were selected from mumps outbreaks in schools in Guangzhou between 2004 and 2005. Each case was matched by gender, age and classroom. Vaccination information was obtained from Children＇s EPI Administrative Computerized System. Vaccine effectiveness （VE） was calculated for 1 or 2 doses of S79 vaccine with 95% confidence intervals （CI）. Results One hundred and ninety-four cases and 194 controls were enrolled into the study. VE of the S79 mumps vaccine for 1 dose versus 0 confer protection 80.4% （95% Cl, 60.0%-90.4%） and VEs against mumps in outbreaks for 1 dose of mumps vaccine are similar among those children aged 4-9 years and aged over 10 years old. Conclusion The live attenuated S79 mumps vaccine can be effective in preventing clinical mumps outbreaks.

关键词： mumps outbreaks case-control studies

Cooperative hunting in a discrete predator-prey system

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International Journal of Biomathematics 2020年第7期13卷 133-158页

作者： Yunshyong Chow Sophia R-J.Jang hua-ming wang Institute of Mathematics Academia Sinica Taipei 10617Taiwan Department of Mathematics and Statistics Texas Tech University LubbockTX 79409USA Department of Statistics Anhui Normal University Wuhu 241003AnhuiP.R.China

We propose and investigate a discrete-time predator-prey system with cooperative hunting in the predator *** model is constructed from the classical Nicholson-Bailey host-parasitoid system with density dependent growth rate.A sufficient condition based on the model parameters for which both populations can coexist is derived,namely that the predator’s maximal reproductive number exceeds *** study existence of interior steady states and their stability in certain parameter *** is shown that the system behaves asymptotically similar to the model with no cooperative hunting if the degree of cooperation is *** cooperative hunting,however,may promote persistence of the predator for which the predator would otherwise go extinct if there were no cooperation.

关键词： Cooperative hunting discrete predator-prey system predator persistence Neimark-Sacker bifurcation

Synthesis and in vitro antitumor activity of novel naphthyridinone derivatives

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Chinese Chemical Letters 2017年第2期28卷 235-239页

作者： Xue-Dong Jia Shuo wang ming-hua wang ming-Liang Liu Gui-Min Xia Xiu-Jun Liu Yun Chai Hong-Wei He Institute of Medicinal Biotechnology Chinese Academy of Medical Sciences and Peking Union Medical College Beijing 100050 China The First Affiliated Hospital of Zhengzhou University Zhengzhou 450052 China

A series of naphthyridinone derivatives based on la（a precursor of Voreloxin） were designed and *** compounds having 〉70%inhibition against HL60 at 30 μmol/L were further evaluated for their in vitro antitumor activity by SRB *** reveal that thiazol-2-yl and 3-aminomethyl-4-benzyloxyimino-3-methylpyrrolidin-l-yl groups are optimal at the N-1 and C-7positions of naphthyridinone core,respectively.10 j exhibits broad-spectrum activity（IC_（50）：〈0.5-6.25 μmol/L） against all of the tested cell lines including Etoposide- and/or la-resistant ones,and is 1.3-fold to 〉100-fold more potent than the two references against eight of these cell lines.

关键词： Naphthyridinones Synthesis Antitumor activity Voreloxin

Recent advances in the recovery of transition metals from spent hydrodesulfurization catalysts

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Tungsten 2021年第3期3卷 305-328页

作者： Jian-Zhang wang Hao Du Afolabi Olayiwola Biao Liu Feng Gao Mei-Li Jia ming-hua wang ming-Lei Gao Xin-Dong wang Shao-Na wang School of Metallurgy Northeastern UniversityShenyang 110819China CAS Key Laboratory of Green Process and Engineering Institute of Process EngineeringChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China Chengde V and Ti New Material Co. Ltd.HBIS Group Co.Ltd.Shijiazhuang 050023China

Hydrodesulfurization(HDS)catalysts are widely used in petrochemical industries,playing a crucial role in desulfurization process to get high-quality *** generation of Al-based spent HDS catalyst is estimated to be 1.2×105 tons per year around the *** spent HDS catalysts have been regarded as an important secondary resource due to their abundant output,considerable metal value,and regeneration potential;however,if improperly handled,it would severely pollute the environment due to high content of heavy ***,the recovery of valuable metals from spent HDS catalysts is of great importance from both resource utilization and environmental protection points of *** this work,recent advances in the spent HDS catalyst treatment technologies have been reviewed,focusing on the recovery of valuable transition metals and environmental ***,typical commercial processes have been discussed,providing in-depth information for peer researchers to facilitate their future research work in designing more effective and environmentally friendly recycling processes.

关键词： Spent hydrodesulfurization catalyst Recycling Hydrometallurgical and pyrometallurgical processes Valuable metals

A new approach for effectively determining fracture network connec- tions in fractured rocks using R tree indexing

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Journal of Coal Science & Engineering(China) 2011年第4期17卷 401-407页

作者： LIU hua-mei wang ming-yu SONG Xian-feng Center for Water @stem Security ＆ College of Resources and Environment Graduate University of Chinese Academy of Sciences Beijing 100049 China

Determinations of fracture network connections would help the investigators remove those ＂meaningless＂ no-flow-passing fractures, providing an updated and more effective fracture network that could considerably improve the computation efficiency in the pertinent numerical simulations of fluid flow and solute transport. The effective algorithms with higher computational efficiency are needed to accomplish this task in large-scale fractured rock masses. A new approach using R tree indexing was proposed for determining fracture connection in 3D stochastically distributed fracture network. By com- paring with the traditional exhaustion algorithm, it was observed that from the simulation results, this approach was much more effective; and the more the fractures were investigated, the more obvious the advantages of the approach were. Furthermore, it was indicated that the runtime used for creating the R tree indexing has a major part in the total of the runtime used for calculating Minimum Bounding Rectangles （MBRs）, creating the R tree indexing, precisely finding out fracture intersections, and identifying flow paths, which are four important steps to determine fracture connections. This proposed approach for the determination of fracture connections in three-dimensional fractured rocks are expected to provide efficient preprocessing and critical database for practically accomplishing numerical computation of fluid flow and solute transport in large-scale fractured rock masses.

关键词： fracture network connection fractured rooks R tree indexing

Vortex identification based on the Liutex method and its effect on fish passage upstream

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Journal of Hydrodynamics 2024年第1期36卷 130-141页

作者： Chun-ying Shen Rui-guo Yang Xiao-tao Shi ming-ming wang Shi-hua He Faculty of Electrical Power Engineering Kunming University of Science and TechnologyKunming650500China Hubei International Science and Technology Cooperation Base of Fish Passage China Three Gorges UniversityYichang443002China Shanghai Investigation Design and Research Institute Co.LtShanghai200434China

Fishway research is important for mitigating the fragmentation of river habitats caused by hydraulic *** vertical slit fishway is a broadly used fishway type because of its high efficiency and adaptability to water ***,the resulting vortex current disrupts the fish passage hence directly affecting fish *** study aims to accurately capture the vortex structure in the fishway and analyze the effect of vortex elements(vortex structure,vortex intensity,etc.)on *** conducted an analysis of the 3-D current flow field in the fishway through the utilization of an experimental model and the large eddy simulation(LES)***,we captured the vortex information in the fishway at different flow rates using the Liutex vortex identification method and investigated the effect of the vortex on fish *** results revealed that the structures inside the fishway pool occupy most of the room,however,the areas with higher vortex strength were primarily located in the vortex near the vertical seam and the mainstream,the vortex strength inside the fishway gradually increases with increasing flow,suppressing fish *** experienced significantly increased resistance when encountering strong *** suggests that the vortex may act as a physical barrier to fish *** findings highlight the potential negative effects of vortex on fish movement and reiterate the importance of understanding vortex dynamics for aquatic environmental *** an effective tool for identifying vortices in fluid flow,the Liutex method demonstrates features of vortex within the fishway,thereby providing important insights into the interaction between fluid dynamics and aquatic organisms.

关键词： Vertical slit fishway vortex identification method Liutex large eddy simulation(LES) fish experiment computational fluid dynamics

Effect of Nd addition on microstructure and tensile properties of laser additive manufactured TC11 titanium alloy

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Transactions of Nonferrous Metals Society of China 2022年第5期32卷 1501-1512页

作者： Wen-gao YAN hua-ming wang Hai-bo TANG Xu CHENG Yan-yan ZHU National Engineering Laboratory of Additive Manufacturing for Large Metallic Components Research Institute for Frontier ScienceBeihang UniversityBeijing 100191China Ningbo Institute of Technology Beihang UniversityNingbo 315800China

Single-layer and multilayer laser additive manufacturing(LAM)for TC11 alloy with different Nd additions was conducted and the effect of Nd addition on microstructure and properties was *** the addition of Nd,the aspect ratio of melting pools of single-layer specimens increases and the columnar-to-equiaxed transition *** originalβgrain size andαplate width of TC11−1.0Nd are significantly reduced compared with those of pure TC11 *** is proposed that the evenly distributed fine Nd_(2)O_(3) precipitates of about 1.51μm are formed preferentially during rapid solidification of melting pool,and they serve as heterogeneous nucleation particles to refine the microstructure in the subsequent solidification and solid-state phase *** to the multiple effects of Nd on the microstructure,the ultimate tensile strength of TC11−1.0Nd increases,while the yield strength,ductility and microhardness decrease compared with those of pure TC11.

关键词： laser additive manufacturing titanium alloy rare-earth element microstructure grain refinement mechanical properties

Effects of sargentgloryvine stem extracts on HepG-2 cellsin vitro andin vivo

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World Journal of Gastroenterology 2011年第23期17卷 2848-2854页

作者： ming-hua wang Min Long Bao-Yi Zhu Shu-Hui Yang Ji-Hong Ren Hui-Zhong Zhang Department of LaboratoryMedicine and Research Center Tangdu Hospital Fourth MilitaryMedical University Xi＇an 710038 Shaanxi Province China

AIM:To observe the effects of sargentgloryvine stem extracts (SSE) on the hepatoma cell line HepG-2 in vitro andin vivo and determine its mechanisms of ***:Cultured HepG-2 cells treated with SSE were analysed by 3-(4,5-Dimethyl-thiazol-2-yl)-2,5Diphenyltetrazolium bromide and clone formation *** cell cycle and apoptosis analysis were conducted by flow cytometric,TdT-Mediated dUTP Nick End Labeling and acridine orange/ethidium bromide staining methods,and protein expression was examined by both reverse transcriptase-polymerase chain reaction and Western *** pathological changes of the tumor cells were observed by haematoxylin and eosin *** growth inhibition and side effects were determined in a xenograft mouse ***:SSE treatment could not only inhibit HepG-2 cell proliferation in a doseand time-dependent manner but also induce apoptosis and cell cycle arrest at the S *** number of colonies formed by SSEtreated tumor cells was fewer than that of the controls (P0.05).Systemic administration of SSE could inhibit the HepG-2 xenograft tumor growth with no obvious toxic side effects on normal ***:SSE can induce apoptosis of HepG-2 cells in vitro and in vivo through decreasing expression of Bcl-xl and Mcl-1 and increasing expression of Bax.

关键词： Sargentgloryvine stem extract Apoptosis Human hepatocellular carcinoma HepG-2 Bcl-2 family