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Low-degree toroidal modes from the Sumatra-Andaman event observed by superconducting gravimeters

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Geodesy and Geodynamics 2019年第6期10卷 477-484页

作者： Chuang Xu Hangtao Yu Guangyu Jian shiqi deng Boyang Zhou Yihao Wu Department of Surveying Engineering School of Civil and Transportation EngineeringGuangdong University of TechnologyNo.100 Waihuan Xi RoadGuangzhou 510006China State Key Laboratory of Geodesy and Earth’s Dynamics Institute of Geodesy and GeophysicsChinese Academy of SciencesNo.340 Xu Dong AvenueWuhan 430077China State Key Laboratory of Information Engineering in Surveying Mapping and Remote SensingWuhan UniversityWuhan 430079China School of Earth Science and Engineering Hohai UniversityNanjing 210098China

The complex frequencies of the low-degree toroidal modes are helpful in constraining the mantle structure.In the early years,the traditional method to detect the low-degree toroidal modes is seismic approach,which is primarily limited by the horizontal noise of seismometers.Recently,it has been proved that gravity method is competitive.Therefore,we re-estimated or newly estimated the complex frequencies of the toroidal modes below 1.5 mHz excited by the 2004 Sumatra-Andaman event using gravity method in this paper.The results show that(1)The quality factors of0 T5-0 T9 and1 T2-1 T3 are estimated from superconducting gravity data for the first time;(2)The estimated frequencies and quality factors for0 T2-0 T9 and1 T2-1 T3 are consistent with those provided by previous publications,which verifies the correctness and effectiveness of our estimations;(3)The maximum difference of frequencies between our results and those from CPREM is on the order of 0.01 mHz and the maximum difference of quality factors is at the level of 10.

关键词： Low-degree toroidal modes Superconducting gravity data Complex frequency Quality factor

The first Choerolophodon (Proboscidea, Gomphotheriidae) skull from China

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Science China Earth Sciences 2011年第9期54卷 1326-1337页

作者： WANG shiqi deng Tao Key Laboratory of Evolutionary Systematics of Vertebrates Institute of Vertebrate Paleontology and Paleoanthropology Chinese Academy of Sciences Beijing 100044 China

Here we report the first discovery of a relatively complete skull of Choerolophodon from the late early Miocene Dalanggou quarry of Linxia Basin, Gansu Province in China. The skull is low and elongated, with two enamel-less and out ward-and-upward curved incisors and the choerolophodont molars. These characters indicate that the new specimen can be as signed to the genus Choerolophodon, as it is quite distinct from other common gomphotheres in northern China such as Gom photherium, Platybelodon, and Sinomastodon. The skull is also primitive in possessing laterally-expanded zygomatic arches, anteriorly-positioned orbits, weakly-developed cheek teeth cement, and retention of a P4. Prior to this discovery, Cho erolophodon was found primarily from the middle-late Miocene of Africa, Eastern Europe, and western and southern Asia. The discovery of this new material expands the known temporal and spatial distributions of this taxon and helps us better un derstand the phylogeny, evolution, and adaptive radiation of gomphotheres in early Miocene of China.

关键词：中国北方头骨长鼻目早中新世临夏盆地晚中新世南部地区空间分布

Evaluation of Medicinal Plant Extracts for Rice Blast Disease Control

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Rice science 2023年第1期30卷 6-10页

作者： TAN Yanping deng shiqi QIN Yonghua XU Xin YU You CUI Liu WANG Chuntai JIANG Changjie LIU Xinqiong Hubei Province Key Laboratory for Protection and Application of Special Plant Germplasm in Wuling Area of China Key Laboratory of State Ethnic Affairs Commission for Biological TechnologyCollege of Life ScienceSouth-Central Minzu UniversityWuhan 430074China Institute of Agrobiological Sciences National Agriculture and Food Research Organization(NARO)Tsukuba 305-8602Japan Rice Research Institute Shandong Academy of Agricultural SciencesJinan 250100China

The potential of medicinal plant extracts to control rice blast fungus Magnaporthe oryzae was investigated. We screened 48 extracts prepared from 8 medicinal plant species and identified 20 extracts with ≥ 10% inhibitory activity against M. oryzae. Among them, ethanol extract of Paris polyphylla, ethyl acetate extract of Phellodendron chinense, and n-butanol extract of Menispermum dauricum plants exhibited 100%, 70% and 50% inhibition of M.

关键词： Plant medicinal extracts

Network pharmacology and experimental validation to reveal the pharmacological mechanisms of Sini decoction(四逆汤)against renal fibrosis

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Journal of Traditional Chinese Medicine 2024年第2期44卷 362-372页

作者： WANG Yan deng Fanying LIU shiqi WANG Yingli Department of Pharmacy Shanxi University of Chinese MedicineJinzhong 030619China Schools of Basic Medical Sciences Heilongjiang University of Chinese MedicineHaerbin 150040China

OBJECTIVE:To investigate the mechanism by which Sini decoction(四逆汤,SND)improves renal fibrosis(Rf)in rats based on transforming growth factor β1/Smad(TGF-β1/Smad)signaling pathway.METHODS:Network pharmacology was applied to obtain potentially involved signaling pathways in SND's improving effects on Rf.The targets of SND drug components and the targets of Rf were obtained by searching databases,such as the Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform(TCSMP)and GeenCard.The intersection targets of two searches were obtained and underwent signaling pathway analysis using a Venn diagram.Then experimental pharmacology was utilized to prove and investigate the effects of SND on target proteins in the TGF-β1/Smad signaling pathway.The Rf rat model was established by unilateral ureteral occlusion(UUO).The expression levels of transforming growth factor,matrix metalloproteinase-9(MMP-9),matrix metal protease-2(MMP-2),connective tissue growth factor(CTGF),and tissue inhibitor of metalloproteinase-1(TIMP-1)were determined by Masson staining of rat renal tissue,and immunohistochemical methods.The expression levels of Smad3,Smad2,and Smad7 in renal tissue were determined by Western blotting(WB).The mechanism of the improving effects of SND on Rf was investigated based on TGF-β1/Smad signaling pathway.RESULTS:A total of 12 drug components of Fuzi(Radix Aconiti Lateralis Preparata),5 drug components of Ganjiang(Rhizoma Zingiber),and 9 drug components of Gancao(Radix Glycy et Rhizoma)were obtained from the database search,and 207 shared targets were found.A total of 1063 Rf targets were found in the database search.According to the Venn diagram,in total,96 intersection targets were found in two database searches.The metabolic pathways involved included TGF-β signaling pathway,phosphatidylinositol-3-kinase/serine-threonine protein kinase signaling(PI3K/Akt)pathway,and hypoxia-inducible factor-1(HIF-1)signaling pathway.Masson staining analysis showed that compared with the model group,the renal

关键词： renal fibrosis network pharmacology transforming growth factor beta1 smad proteins Sini decoction

Periodic event-triggered secure consensus for networked mechanical systems under Denial-of-Service attacks

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Control Theory and Technology 2024年第1期22卷 1-13页

作者： shiqi Zheng Zhipeng Li Chao Zhai Peng Shi School of Automation China University of GeosciencesWuhan430074HubeiChina School of Electrical and Electronic Engineering The University of AdelaideAdelaideSA5005Australia School of Electronic Electrical Engineering and PhysicsFujian University of TechnologyFuzhou350100FujianChina

This paper concentrates on the secure consensus problem of networked mechanical/Euler–Lagrange systems.First,a new periodic event-triggered(PET)secure distributed observer is proposed to estimate the leader information.The proposed distributed observer only relies on the PET data from its neighbors,which can significantly reduce the communication and computational burden.More importantly,it is secure in the sense that it can work normally regardless of the Denial-of-Service(DoS)attacks.Second,based on the proposed distributed observer,an adaptive fuzzy control law is proposed for each Euler–Lagrange system.A PET mechanism is integrated into the controller,which can reduce the control update.This is helpful for both energy saving and fault tolerance of actuators.Moreover,the PET mechanism naturally makes the controller easy to be implemented in digital platform.The property of fuzzy logic systems and Gronwall inequality are skillfully utilized to show the stability of the closed-loop system.Finally,the proposed control scheme is verified on real Euler–Lagrange systems,which contain a robot manipulator and several servo motors.

关键词： Output regulation Mechanical/Euler-Lagrange systems Periodic event-triggered mechanism Denial-of-Service attacks

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Message from Editors

CES Transactions on Electrical Machines and Systems 2024年第1期8卷 1-2页

作者： shiqi Ji Frontier Coumn

IN recent years,the electrical machines and systems have grown so rapidly with more and more applications in emerging civilian industries as well as cutting-edge areas.A group of novel and exciting technologies have been developed every year.First,the research of motors in new and extreme fields have constantly brought amazing progress to achieve better performance through new technologies such as digitalization,etc.Meanwhile,the fast development of power electronics in recent decades has also changed the overall system to be more flexible,and widely extent our boundary of research area.What is more.

关键词： extreme Message constantly

Production of linear alkylbenzene over Ce containing Beta zeolites

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Chinese Journal of Chemical Engineering 2024年第3期67卷 220-227页

作者： shiqi Zhang Shengzhi Gan Baoyu Liu Jinxiang Dong School of Chemical Engineering and Light Industry Guangdong Provincial Key Laboratory of Plant Resources BiorefineryGuangzhou Key Laboratory of Clean Transportation Energy ChemistryGuangdong University of TechnologyGuangzhou 510006China Jieyang Branch of Chemistry and Chemical Engineering Guangdong Laboratory(Rongjiang Laboratory) Jieyang 515200China

Ce-encapsulated Beta zeolite was synthesized by a one-pot hydrothermal method with citric acid complexing Ce in the absence of Na species.Additional citric acid can effectively prevent the deposition of Ce species during the hydrothermal synthesis of zeolites,leading to uniform distribution of Ce cluster in the framework of Beta zeolites.Moreover,the sodium-free synthesis system resulted that the Brønsted acid sites were mainly located on the straight channels and external surface of Beta zeolites,improving the utilization of Brønsted acid sites.In addition,Ce encapsulated Beta zeolites showed enhanced activity and robust stability in the alkylation of benzene with 1-dodecene based on the synergistic effect between Ce species and Brønsted acid sites,which pave the way for its practical application in the production of alkylbenzene.

关键词： Beta zeolites Catalysis Alkylation Long-chain olefins

Cholesky GAS models for large time-varying covariance matrices

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Journal of Management Science and Engineering 2024年第1期9卷 115-142页

作者： Tingguo Zheng shiqi Ye Department of Statistics and Data Science School of EconomicsXiamen UniversityXiamen361005China Wang Yanan Institute for Studies in Economics Xiamen UniversityXiamen361005China Paula and Gregory Chow Institute for Studies in Economics Xiamen UniversityXiamen361005China

This paper develops a new class of multivariate models for large-dimensional time-varying covariance matrices,called Cholesky generalized autoregressive score(GAS)models,which are based on the Cholesky decomposition of the covariance matrix and assume that the parameters are score-driven.Specifically,two types of score-driven updates are considered:one is closer to the GARCH family,and the other is inspired by the stochastic volatility model.We demonstrate that the models can be estimated equation-wise and are computationally feasible for high-dimensional cases.Moreover,we design an equationwise dynamic model averaging or selection algorithm which simultaneously extracts model and parameter uncertainties,equipped with dynamically estimated model parameters.The simulation results illustrate the superiority of the proposed models.Finally,using a sizeable daily return dataset that includes 124 sectors in the Chinese stock market,two empirical studies with a small sample and a full sample are conducted to verify the advantages of our models.The full sample analysis by a dynamic correlation network documents significant structural changes in the Chinese stock market before and after COVID-19.

关键词： Cholesky decomposition GAS Dynamic conditional correlations Dynamic model averaging

Neogene integrative stratigraphy,biotas,and paleogeographical evolution of the Qinghai-Tibetan Plateau and its surrounding areas

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Science China Earth Sciences 2024年第4期67卷 1326-1359页

作者： Tao deng Xiaomin FANG Qiang LI shiqi WANG Feixiang WU Sukuan HOU Jiao MA Qigao JIANGZUO Danhui SUN Yan ZHENG Qinqin SHI Boyang SUN Lu LI Key Laboratory of Vertebrate Evolution and Human Origins Institute of Vertebrate Paleontology and PaleoanthropologyChinese Academy of SciencesBeijing 100044China CAS Center for Excellence in Life and Paleoenvironment Beijing 100044China University of Chinese Academy of Sciences Beijing 100049China CAS Center for Excellence in Tibetan Plateau Earth Sciences and Key Laboratory of Continental Collision and Plateau Uplift Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China Key Laboratory of Orogenic Belts and Crustal Evolution School of Earth and Space SciencesPeking UniversityBeijing 100871China

The remarkable uplift of the Tibetan Plateau in the Neogene had great impacts on the climate and environment of East Asia and even the world.Therefore,establishment of the Neogene stratigraphic framework of the Tibetan Plateau is of great significance to research in various fields of geosciences.Based on marine sediments,the international chronostratigraphic system of the Neogene is divided into six stages in the Miocene and two stages in the Pliocene.Since the beginning of the Cenozoic,the share of terrestrial strata on continents has increased rapidly.By the Neogene,it had far exceeded that of marine strata,and almost all deposits on the Tibetan Plateau and its surrounding areas were terrestrial strata.In China,the Miocene includes five stages and the Pliocene includes two stages.Except for the Tunggurian of the Miocene,which has a lower boundary at 15 Ma,the other stages have the same paleomagnetic definitions and time intervals as the corresponding international marine stages.Mammalian fossils play a very important role in the division and correlation of Cenozoic terrestrial strata,and rodent,carnivore,proboscidean,perissodactyl and artiodactyl fossils are especially important in Neogene terrestrial biostratigraphy.There are many basins with well-exposed strata and abundant mammalian fossils in the Tibetan Plateau.The lower boundary stratotype sections of the Neogene Xiejian and Bahean stages are located respectively in the Xining and Linxia basins,and there are precise paleomagnetic dates in coordination with mammalian fossils.The lower boundary stratotypes of other stages can also be effectively determined in the Tibetan Plateau.Many first appearing mammalian genera in East Asia also appeared in the Tibetan Plateau and its surrounding areas,especially in the Linxia Basin on the northeast margin and in the Siwaliks on the southwest margin.Among them,Prodeinotherium first appeared at the bottom of the Miocene in the Siwaliks,and the earliest Hipparion of the Old World first appeared at the bottom of the Bahea

关键词： Tibetan Plateau Neogene Terrestrial stratum Mammalian fossil Paleomagnetism