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Dammarane-type saponins from steamed leaves of Panax notoginseng

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Natural Products and Bioprospecting 2011年第3期1卷 124-128页

作者： Qing LIU Jun-Jiang LV Min XU Dong WANG Hong-Tao ZHU Chong-Ren YANG Ying-Jun ZHANG State Key Laboratory of Phytochemistry and Plant Resources in West China Kunming Institute of BotanyChinese Academy of SciencesKunming 650201China graduate University of Chinese Academy of Sciences Beijing 100049China Weihe Biotech Research and Development Center Yuxi 653101China

Four new dammarane-type triterpenoid saponins,namely notoginsenosides SFt1-SFt4(1-4)were isolated from the steamed leaves of Panax notoginseng(Burk.)***(Araliaceae),together with 17 known *** structures were established on the basis of detailed spectroscopic analyses and acidic *** known ginsenosides Rk2 and Rh3 were obtained from *** for the first *** of these new saponins showed no in vitro cytotoxicity against five human cancer cell lines(HL-60,SMMC-7712,A-549,MCF-7,and SW480).

关键词： Panax notoginseng steamed leave dammarane-type saponin notoginsenoside

Impacts of a GCM's Resolution on MJO Simulation

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Advances in Atmospheric Sciences 2008年第1期25卷 139-156页

作者：贾小龙李崇银凌健 Chidong ZHANG National Climate Center Beijing 100081 State Key Laboratory of Numerical Modeling for Atmospheric Sciences andGeophysical Fluid Dynamics （ LASG） Institute of Atmospheric PhysicsChinese Academy of Sciences Beijing 100029 Institute of Meteorology PLA University of Science and Technology Nanjing 211101 graduate University of Chinese Academy of Sciences Beijing 100049 Rosenstiel School of Marine and Atmospheric Science University of Miami Miami Florida USA

Long-term integrations are conducted using the Spectral Atmospheric Model （referred to as SAMIL）, which was developed in the Laboratory for Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics （LASG） in the Institute of Atmospheric Physics （IAP）, with different resolutions to inves-tigate sensitivity of the Madden-Julian Oscillation （MJO） simulations to the model＇s resolution （horizontal and vertical）. Three resolutions of the model, R15L9, R42L9 and R42L26, with identical physical processes, all produced the basic observed features of the MJO, including the spatiotemporal space-time spectra and eastward propagation. No fundamental differences among these simulations were found. This indicates that the model resolution is not a determining factor for simulating the MJO. Detailed differences among these modeling results suggest, however, that model resolution can substantially affect the simulated MJO in certain aspects. For instance, at a lower horizontal resolution, high frequency disturbances were weaker and the structures of the simulated MJO were better defined to a certain extent. A higher vertical resolution led to a more realistic spatiotemporal spectrum and spatial distribution of MJO precipitation. Meanwhile, increasing the model＇s resolution improved simulation of the climatology. However, increasing the resolution should be based on improving the cumulus parameterization scheme.

关键词： MJO GCM simulation model resolution

Mapping runoff based on hydro-stochastic approach for the Huaihe River Basin, China

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Journal of Geographical Sciences 2011年第3期21卷 441-457页

作者： YAN Ziqi XIA Jun Lars GOTTSCHALK Institute of Geographic Sciences and Natural Resources Research CAS Beijing 100101 China graduate University of Chinese Academy of Sciences Beijing 100049 China Department of Geosciences University of Oslo N-0315 Oslo Norway

Theoretical difficulties for mapping and for estimating river regime characteristics in a large-scale basin remain because of the nature of the variable under study： river flows are related to a specific area, i.e. the drainage basin, and are hierarchically organized in space through the river network with upstream-downstream dependencies. Another limitation is there are not enough gauge stations in developing countries. This presentation aims at developing the hydro-stochastic approach for producing choropleth maps of average annual runoff and computing mean discharge along the main river network for a large-scale basin. The approach applied to mean annual runoff is based on geostatistical interpolation proce- dures coupled with water balance and data uncertainty analyses. It is proved by an applica- tion in the upstream at Bengbu in the Huaihe River Basin, a typical large-scale basin in China. Hydro-stochasitic approach in a first step interpolates to a regular grid net and in a second step the grid values are integrated along rivers, The interpolation scheme includes a constraint to be able to account for the lateral water balance along the rivers. Grid runoff map with 10 km x 10 km resolution and the discharge map along the river with the 1 km basic length unit are the main results in this study. This kind of statistic approach can be widely used because it avoids the complexity of hydrological models and does not depend on the meteorological data.

关键词： kriging method hydro-stochastic runoff water balance Huaihe River Basin

Rauvotetraphyllines A-E, new indole alkaloids from Rauvolfia tetraphylla

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Natural Products and Bioprospecting 2012年第2期2卷 65-69页

作者： Yuan GAO Dong-Sheng ZHOU Ling-Mei KONG Ping HAI Yan LI Fei WANG Ji-Kai LIU State Key Laboratory of Phytochemistry and Plant Resources in West China Kunming Institute of BotanyChinese Academy of SciencesKunming 650201China BioBioPha Co. Ltd.Kunming 650201China graduate University of Chinese Academy of Sciences Beijing 100039China

Five new indole alkaloids rauvotetraphyllines A-E(1-5),together with eight known analogues,were isolated from the aerial parts of Rauvolfia *** structures were established by means of spectroscopic methods.

关键词： Rauvolfia tetraphylla indole alkaloid rauvotetraphylline

The state-of-the-art in computer generated holography for 3D display

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Light(Advanced Manufacturing) 2022年第3期3卷 168-196页

作者： David Blinder Tobias Birnbaum Tomoyoshi Ito Tomoyoshi Shimobaba Department of Electronics and Informatics(ETRO) Vrije Universiteit Brussel(VUB)Pleinlaan 2B-1050 BrusselBelgium IMEC Kapeldreef 75B-3001 LeuvenBelgium graduate School of Engineering Chiba University1-33 Yayoi-choInage-kuChibaChibaJapan

Holographic displays have the promise to be the ultimate 3D display technology,able to account for all visual *** advances in photonics and electronics gave rise to high-resolution holographic display prototypes,indicating that they may become widely available in the near *** major challenge in driving those display systems is computational:computer generated holography(CGH)consists of numerically simulating diffraction,which is very computationally *** goal in this paper is to give a broad overview of the state-of-the-art in *** make a classification of modern CGH algorithms,we describe different algorithmic CGH acceleration techniques,discuss the latest dedicated hardware solutions and indicate how to evaluate the perceptual quality of *** summarize our findings,discuss remaining challenges and make projections on the future of CGH.

关键词： Digital holography Holographic display Computer generated holography High-performance computing FPGA Deep learning Visual quality assessment

Sedimentary processes in Zenisu deep-sea channel revealed by side-scan imagery

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Chinese Journal of Oceanology and Limnology 2005年第4期23卷 368-375页

作者：吴时国郭军华 TOKUYAMA Hidekazu Institute of Oceanology Chinese Academy of SciencesQingdao 266071 China Institute of Oceanology Chinese Academy of SciencesQingdao 266071 China Graduate School of the Chinese Academy of SciencesBeijing 100049 China Ocean Research Institute University of Tokyo Tokyo 2370061 Japan

Side-scan sonar data collected by Cruises 99-09 Leg 2 and 00-06 Leg l of R/V Yokosuka were used to reveal the sedimentary processes in Zenisu deep-sea channel. The middle and lower segments of the channel are rich in turbidite and other debrite deposits. By high-resolution imaging, three sedimentary processes were distinguished with distinct acoustic features. 1. Slumps and slides occur with contrasting backscatter, rough surface textures, blockings, and acoustic shadows at headwalls. They are very extensive and often in lobate form downslope. 2. Debris flow has uniform, general medium backscatter, sometimes showing marbling/lineation in lobate form. 3. Turbidity current is characterized by low backscatter confined to the channel as acoustic signal is attenuated. Regional tectonics must be the dominating factor that controls deposition pattern in this area.

关键词： side-scan sonar image sedimentary processes deep-sea channel Nankai Trough

Inhibitory mechanism of angiotensin-converting enzyme inhibitory peptides from black tea

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2021年第7期22卷 575-589页

作者： Yating LU Yu WANG Danyi HUANG Zhuang BIAN Peng LU Dongmei FAN Xiaochang WANG Tea Research Institute College of Agriculture and BiotechnologyZhejiang UniversityHangzhou 310058China Department of Applied Biological Chemistry Graduate School of Agricultural and Life SciencesThe University of TokyoTokyo 113-8657Japan

The aim of this work is to discover the inhibitory mechanism of tea peptides and to analyse the affinities between the peptides and the angiotensin-converting enzyme(ACE)as well as the stability of the complexes using in vitro and in silico *** peptide sequences identified from tea,namely peptides I,II,III,and IV,were used to examine ACE inhibition and *** half maximal inhibitory concentration(IC_(50))values of the four peptides were(210.03±18.29),(178.91±5.18),(196.31±2.87),and(121.11±3.38)μmol/L,*** results of Lineweaver-Burk plots showed that peptides I,II,and IV inhibited ACE activity in an uncompetitive manner,which requires the presence of *** III inhibited ACE in a noncompetitive manner,for which the presence of substrate is not *** docking simulations showed that the four peptides did not bind to the active sites of ACE,indicating that the four peptides are allosteric *** binding free energies calculated from molecular dynamic(MD)simulation were-72.47,-42.20,-52.10,and-67.14 kcal/mol(1 kcal=4.186 kJ),r *** lower IC_(50)value of peptide IV may be attributed to its stability when docking with ACE and changes in the flexibility and unfolding of *** four bioactive peptides with ACE inhibitory ability can be incorporated into novel functional ingredients of black tea.

关键词： Black tea Angiotensin-1-converting enzyme(ACE)inhibitory peptide Kinetic study Molecular docking Molecular dynamic(MD)simulation

Caenorhabditis elegans mom-4 is required for the activation of the p38 MAPK signaling pathway in the response to Pseudomonas aeruginosa infection

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Protein & Cell 2013年第1期4卷 53-61页

作者： Ajing Xu Guojun Shi Feng Liu Baoxue Ge Department of Pharmacology Xinhua HospitalSchool of MedicineShanghai 200092China Shanghai pulmonary hospital Tongji University School of MedicineShanghai 200092China Lab of Signal Transduction Institute of Health SciencesShanghai Institutes for Biological SciencesChinese Academy of Sciences and Shanghai Jiao-Tong University School of MedicineShanghai 200025China graduate School of the Chinese Academy of Sciences Beijing 100049China

The p38 mitogen-activated protein kinase(MAPK)plays an evolutionarily conserved role in the cellular re-sponse to microbial infection and environmental *** of p38 is mediated through phosphorylation by upstream MAPKK,which in turn is activated by *** the Caenorhabditis elegans,the p38 MAPK(also called PMK-1)signaling pathway has been shown to be required in its resistance to bacterial ***,how different upstream MAP2Ks and MAP3Ks specifically contribute to the activation of PMK-1 in response to bacterial infection still is not clearly *** using double-stranded RNA-mediated interference(RNAi)and genetic mutants of ***,we demonstrate that *** MOM-4,a mammalian TAK1 homolog,is required for the resistance of *** to a *** *** have also found that the MKK-4 of *** is required for *** resistance,but not through the regulation of *** summary,our results indicate that different upstream MAPKKKs or MAPKKs regulate the activation of PMK-1 in response to ***.

关键词： C.elegans MAPK innate immunity p38 P.aeruginosa PA-14 MOM-4

Identification of sympatric bat species by the echolocation calls

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生物学前沿:英文版 2008年第2期3卷 227-231页

作者： Keping SUN Jiang FENG Longru JIN Ying LIU Yunlei JIANG Department of Environmental Science and Engineering Northeast Normal UniversityChangchun 130024China Institute of Applied Ecology Chinese Academy of SciencesShenyang 110016China graduate School of Chinese Academy of Sciences Beijing 100039China Faculty of Animal Science and Technology Jilin Agricultural UniversityChangchun 130000China

One hundred and thirty-eight echolocation calls of 63 free-flying individuals of five bat species(Rhinolophus ferrumequinum,Myotis formosus,Myotis ikonnikovi,Myotis daubentoni and Murina leucogaster)were recorded(by ultrasonic bat detector(D980))in Zhi’an village of Jilin Province,*** to the frequency-time spectra,these calls were categorized into two types:FM/CF(constant frequency)/FM(***)and FM(frequency modulated)(***,***,*** and ***).Sonograms of the calls of *** could easily be distinguished from those of the other four *** the calls of the remaining four species,six echolocation call parameters,including starting frequency,ending frequency,peak frequency duration,longest inter-pulse interval and shortest inter-pulse interval,were examined by stepwise discriminant *** results show that 84.1%of calls were correctly classified,which indicates that these parameters of echolocation calls play an important role in identifying bat *** parameters can be used to test the accuracy of general predictions based on bats’morphology in the same forest and can provide essential information for assessing patterns of bat habitat use.

关键词： bats echolocation call identification of species discriminant analysis