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Furostanol saponins with inhibitory action against COX-2 production from Tupistra chinensis rhizomes

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Chinese Chemical Letters 2007年第10期18卷 1239-1242页

作者： Kun Zou jun Zhi Wang jun Wu Yuan Zhou Chuang Liu fei jun Dan Ya Xiong Zhang Jin Yang Hubei Province Key Laboratory of Natural Products Research and Development College of Chemistry and Life Sciences China Three Gorges University Yichang 443002 China Guangdong Key Laboratory of Marine Materia Medica South China Sea Institute of Oceanology Chinese Academy of Sciences Guangzhou 510301 China

Two furostanol saponins were obtained from the n-butanol fraction of methanol extract from Tupistra chinensis rhizomes, a folk medicine of Shennongjia Forest District of Hubei Province. Their structures were determined as （25S）-26-O-（β-D-glucopyranosyl）- furost-1β, 3β, 22α, 26-tetrol-3-O-β-D-glucopyranosyl-（1 → 4）-β-D-glucopyranosyl-（1 → 2）-β-D-glucopyranoside （1） and （25R）- 26-O-（β-D-glucopyranosyl）-furost-1β, 3β 22a, 26-tetrol 3-O-β-D-glucopyranosyl-（1 → 4）-β-D-glucopyranosyl-（1 → 2）-β-D-glu- copyranoside （2）, on basis of chemical and spectroscopic evidences. 1 and 2 displayed marked inhibitory action towards COX-2 production in macrophages of the rat abdomen induced by LPS at 20 μg/mL.

关键词： Tupistra chinensis Bak. Furostanol saponin COX-2 Folk medicines

Topology evolutions of silhouettes

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第10期8卷 1671-1680页

作者： DAI jun-fei KIM junho ZENG Hua-yi GU Xian-feng YAU Shing-tung Center of Mathematical Sciences Zhejiang University Hangzhou 310027 China Visualization Laboratory State University of New York Stony Brook NY 11794 USA Department of Mathematics Harvard University Boston MA02138 USA

We give the topology changing of the silhouette in 3D space while others study the projections in an image. Silhou- ettes play a crucial role in visualization, graphics and vision. This work focuses on the global behaviors of silhouettes, especially their topological evolutions, such as splitting, merging, appearing and disappearing. The dynamics of silhouettes are governed by the topology, the curvature of the surface, and the view point. In this paper, we work on a more theoretical level to give enu- merative properties of the silhouette including: the integration of signed geodesic curvature along a silhouette is equal to the view cone angle; in elliptic regions, no silhouette can be contained in another one; in hyperbolic regions, if a silhouette is homotopic to a point, then it has at least 4 cusps; finally, critical events can only happen when the view point is on the aspect surfaces (ruled surface of the asymptotic lines of parabolic points with surface itself). We also introduce a method to visualize the evolution of silhouettes, especially all the critical events where the topologies of the silhouettes change. The results have broad applications in computer vision for recognition, graphics for rendering and visualization.

关键词： Topological change Silhouette Geodesic curvature Cusp

Oxidation behavior of Nb–24Ti–18Si–2Al–2Hf–4Cr and Nb–24Ti–18Si–2Al–2Hf–8Cr hypereutectic alloys at 1250°C

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Rare Metals 2017年第3期36卷 168-173页

作者： Zhen Hong Hu Zhang jun-fei Weng Lin-Fen Su Zhen Li Li-Na Jia School of Materials Science and Engineering Beihang UniversityBeijing 100191China

Nb-24Ti-18Si-2Al-2Hf-4Cr and Nb-24Ti-18Si-2Al-2Hf-8Cr alloys were prepared by arc melting in a water-cooled crucible under argon *** characteristics and oxidation resistance of the alloys at 1250 ℃ were *** results show that,when the Cr content is 4 at%,the microstructures consist of （Nb,Ti）ss and Nb5Si3;as Cr content increases to 8 at%,C14 Laves phase Cr2Nb is *** isothermal oxidation tests show that the oxidation kinetics of the two alloys follow similar *** weight gains of the two alloys after oxidation at 1250 ℃ for 100 h are 235.61 and 198.50 ***-2,*** oxidation,SiO2,TiO2,Nb2O5 and CrNbO4 are formed at ***,Ti2Nb10O29 is formed after oxidation for 20 min and begins to change into TiNb2O7 as the oxidation ***2 is formed as solid state at first but later evolves into glassy state to improve the cohesion of the *** oxidation for 100 h,oxidation products consist of SiO2,TiNb2O7,Nb2O5 and CrNbO4.

关键词： Nb-Si-based alloy lntermetallics Microstructural characteristics Oxidation

A virtual service placement approach based on improved quantum genetic algorithm

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Frontiers of Information Technology & Electronic Engineering 2016年第7期17卷 661-671页

作者： Gang XIONG Yu-xiang HU Le TIAN Ju-long LAN jun-fei LI Qiao ZHOU National Digital Switching System Engineering&Technological Research Center Zhengzhou 450002China Department of Mathematics and Computer Science University of AntwerpAntwerp 2020Belgium

Despite the critical role that middleboxes play in introducing new network functionality,management and innovation of them are still severe challenges for network operators,since traditional middleboxes based on hardware lack service flexibility and ***,though new networking technologies,such as network function virtualization(NFV) and softwaredefined networking(SDN),are considered as very promising drivers to design cost-efficient middlebox service architectures,how to guarantee transmission efficiency has drawn little attention under the condition of adding virtual service process for ***,we focus on the service deployment problem to reduce the transport delay in the network with a combination of NFV and ***,a framework is designed for service placement decision,and an integer linear programming model is proposed to resolve the service placement and minimize the network transport *** a heuristic solution is designed based on the improved quantum genetic *** results show that our proposed method can calculate automatically the optimal placement *** scheme can achieve lower overall transport delay for a network compared with other schemes and reduce 30% of the average traffic transport delay compared with the random placement scheme.

关键词： Software-defined networking(SDN) Network function virtualization Quantum genetic algorithm Middlebox

Microstructures and high-temperature oxidation behavior of directionally solidified Nb-Si-based alloys with Re additions

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Rare Metals 2023年第1期42卷 273-280页

作者： Jie-Chao Zhang Li-Na Jia jun-fei Weng Lin-Fen Su Bin Kong Hu Zhang School of Materials Science and Engineering Beihang UniversityBeijing100191China

High-temperature oxidation behavior of directionally solidified(DS) Nb-Si-based alloys with Re additions was investigated at 1200 and 1250℃,*** and high-temperature oxidation behavior of the alloys were *** show that the microstructures in vertical section of Nb-24Ti-15Si-4Cr-2Al-2Hf-xRe(x=0,1,3;at%) alloys grow parallel to the withdrawal direction and the cross section exhibits bud-like *** bud-like structures become finer with more Re *** weight gain of the Nb-24Ti-15Si-4Cr-2Al-2Hf-3Re alloy after oxidation at 1200℃ for 100 h is 198.1 mg·cm^(-2),and it is a bit higher at 1250℃.The other two alloys perform somewhat *** influence of Re addition on the oxidation resistance at 1250℃ is more significant than that at 1200 ℃.Although Re addition does not benefit obviously the high-temperature oxidation resistance of the DS samples,it does not compromise the oxidation resistance with a certain amount of Re additions in contrast with the alloy without Re addition.

关键词： Nb-Si alloys Directional solidification Rhenium addition Oxidation behavior Microstructure

Grain yield,nitrogen use efficiency and physiological performance of indica/japonica hybrid rice in response to various nitrogen rates

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Journal of Integrative Agriculture 2023年第1期22卷 63-79页

作者： ZHOU Qun YUAN Rui ZHANG Wei-yang GU jun-fei LIU Li-jun ZHANG Hao WANG Zhi-qin YANG Jian-chang Jiangsu Key Laboratory of Crop Genetics and Physiology/Jiangsu Key Laboratory of Crop Cultivation and Physiology/Jiangsu Co-Innovation Center for Modern Production Technology of Grain Crops College of AgricultureYangzhou UniversityYangzhou 225009P.R.China

Utilizing the heterosis of indica/japonica hybrid rice(IJHR)is an effective way to further increase rice grain *** application of nitrogen(N)fertilizer plays a very important role in using the heterosis of IJHR to achieve its great yield ***,the responses of the grain yield and N utilization of IJHR to N application rates and the underlying physiological mechanism remain *** purpose of this study was to clarify these *** rice cultivars currently used in rice production,an IJHR cultivar Yongyou 2640(YY2640),a japonica cultivar Lianjing 7(LJ-7)and an indica cultivar Yangdao 6(YD-6),were grown in the field with six N rates(0,100,200,300,400,and 500 kg ha^(-1))in 2018 and *** results showed that with the increase in N application rates,the grain yield of each test cultivar increased at first and then decreased,and the highest grain yield was at the N rate of 400 kg ha^(-1)for YY2640,with a grain yield of 13.4 t ha^(-1),and at 300 kg ha^(-1)for LJ-7 and YD-6,with grain yields of 9.4–10.6 t ha^(-1).The grain yield and N use efficiency(NUE)of YY2640 were higher than those of LJ-7 or YD-6 at the same N rate,especially at the higher N *** compared with LJ-7 or YD-6,YY2640 exhibited better physiological traits,including greater root oxidation activity and leaf photosynthetic rate,higher cytokinin content in the roots and leaves,and more remobilization of assimilates from the stem to the grain during grain *** results suggest that IJHR could attain both higher grain yield and higher NUE than inbred rice at either low or high N application *** shoot and root traits of the IJHR contribute to its higher grain yield and NUE,and a higher content of cytokinins in the IJHR plants plays a vital role in their responses to N application rates and also benefits other physiological processes.

关键词： indica/japonica hybrid rice grain yield nitrogen use efficiency cytokinins non-structural carbohydrate root activity

NUMERICAL SIMULATION OF IRREGULAR WAVE-SIMULATING IRREGULAR WAVE TRAIN

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Journal of Hydrodynamics 2010年第4期22卷 537-545页

作者： LIANG Xiu-feng YANG Jian-min LI jun XIAO Long-fei LI Xin State Key Laboratory of Ocean Engineering Shanghai Jiao Tong University Shanghai 200030 China

In real sea states,damage incidents on offshore floating structures are not due to the whole time series of wave elevation characterized as statistical one but due to few extreme waves or wave groups in irregular wave ***,using CFD tools to precisely simulate predetermined irregular wave train will lay sound basis for understanding the local characteristic of the flow field and impact loads on offshore floating structures when damage incidents *** this article,the generation of single extreme wave is investigated in a numerical wave ***,experimental irregular wave train is decomposed into certain number of small-amplitude *** Fourier series expansion is performed to determine the amplitude and initial phase angle of each wave component.A hydrodynamic transfer function is used to calculate the amplitude of wave-maker motion associated with each wave *** superposition is carried out on all of the wave-maker motion components to get the final wave-maker *** the wave-maker motion as input,simulation of the single extreme irregular wave train is modeled *** the method is applied to simulating a much more complicated irregular wave *** again main features of the complicated irregular wave train are reproduced compared with experiment carried out in the new deepwater experimental basin at Shanghai Jiao Tong *** the simulation,dynamic mesh method is enabled to model the piston-type wave-maker,the Volume Of Fluid（VOF） method is employed to capture the free surface and a dissipation zone is introduced to deal with wave reflection.

关键词： numerical wave tank irregular wave train Volume of Fluid (VOF) dynamic mesh

Synthesis, Crystal Structure and Anti-breast Cancer Activity of ((3S,5R)-5-((1H-1,2,4-triazol-1-yl)methyl)-5-(2,4-difluorophenyl)tetrahydrofuran-3-yl)methyl 4-Methylbenzenesulfonate

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Chinese Journal of Structural Chemistry 2019年第8期38卷 1337-1343页

作者： HAN Hao ZHANG Zhi-Fang ZHANG jun-fei ZHANG Bin Tongliao Inner Mongolia Autonomous RegionChina Nursing Department Tongliao City HospitalTongliaoInner Mongolia Autonomous RegionChina The First Affiliated Hospital of Inner Mongolia University for theNationlities TongliaoInner Mongolia Autonomous RegionChina

The new heterocycle compound ((3S,5R)-5-((1H-1,2,4-triazol-1-yl)methyl)-5-(2,4-difluorophenyl)tetrahydrofuran-3-yl)methyl 4-methylbenzenesulfonate (1), designed using((3R,5S)-5-(2,4-difluorophenyl)-5-iodotetrahydrofuran-3-yl)methyl isobutyrate(2) as the start material, was successfully obtained via multiple synthesis route and finally characterized by IR, ~1H NMR, and single-crystal X-ray crystallography. In addition, the in vitro anticancer activities of the newly synthesized complex 1 have been emulated against three human breast cancer cell lines BT474, MCF7 and MB.

关键词： heterocycles X-ray crystallography anticancer activity

Enhanced tolerance to drought in transgenic rice plants overexpressing C_4 photosynthesis enzymes

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The Crop Journal 2013年第2期1卷 105-114页

作者： jun-fei Gu Ming Qiu Jian-Chang Yang Key Laboratory of Crop Genetics and Physiology of Jiangsu Province College of AgricultureYangzhou University

Maize-specific pyruvate orthophosphate dikinase(PPDK) was overexpressed in rice independently or in combination with the maize C4-specific phosphoenolpyruvate carboxylase(PCK). The wild-type(WT) cultivar Kitaake and transgenic plants were evaluated in independent field and tank experiments. Three soil moisture treatments,well-watered(WW), moderate drought(MD) and severe drought(SD), were imposed from 9d post-anthesis till maturity. Leaf physiological and biochemical traits, root activities,biomass, grain yield, and yield components in the untransformed WT and two transgenic rice lines(PPDK and PCK) were systematically studied. Compared with the WT, both transgenic rice lines showed increased leaf photosynthetic rate: by 20%–40% under WW, by45%–60% under MD, and by 80%–120% under SD. The transgenic plants produced 16.1%,20.2% and 20.0% higher grain yields than WT under the WW, MD and SD treatments,respectively. Under the same soil moisture treatments, activities of phosphoenolpyruvate carboxylase(PEPC) and carbonic anhydrase(CA) in transgenic plants were 3–5-fold higher than those in WT plants. Compared with ribulose-1,5-bisphosphate carboxylase, activities of PEPC and CA were less reduced under both MD and SD treatments. The transgenic plants also showed higher leaf water content, stomatal conductance, transpiration efficiency, and root oxidation activity and a stronger active oxygen scavenging system than the WT under all soil moisture treatments, especially MD and SD. The results suggest that drought tolerance is greatly enhanced in transgenic rice plants overexpressing C4photosynthesis enzymes. This study was performed under natural conditions and normal planting density to evaluate yield advantages on a field basis. It may open a new avenue to droughttolerance breeding via overexpression of C4enzymes in rice.

关键词： Pyruvate orthophosphate dikinase(PPDK) C4-specific phosphoenolpyruvate carboxylase(PEPC) and PPDK(PCK) Transgenic rice Photosynthesis Drought tolerance