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A paleontological perspective of vertebrate origin

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Chinese Science Bulletin 2003年第8期48卷 725-735页

作者： SHU Degan Early Life Institute & Department of Geology, Northwest University, Xi抋n, 710069, china school of Earth Sciences and Resources, china University of Geosciences, {3., 100083. china (e-mail: elidgshu@ ***) Early Life Institute & Department of Geology Northwest University China School of Earth Sciences and Resources China University of Geosciences

The Early Cambrian Haikouichthys and Haikouella have been claimed to be related to contribute in an important way to our understanding of vertebrate origin, but there have been heated debates about how exactly they are to be interpreted. New discoveries of numerous speci-mens of Haikouichthys not only confirm the identity of pre-viously described structures such as the dorsal and the ven-tral fins, and chevron-shaped myomeres, but also reveal many new important characteristics, including sensory or-gans of the head (e.g. large eyes), and a prominent notochord with differentiated vertebral elements. This 揻irst fish?ap-pears, however, to retain primitive reproductive features of acraniates, suggesting that it is a stem-group craniates. A new order (Myllokunmingiida) and a new family (Myllo-kunmingiidae) are erected, and a new species, Zhongjianich-thys rostratus (gen. et sp. nov.), is described herein. Over 1400 newly-discovered specimens of Haikouella provide a wealth of anatomical information on this organism. It differs from chordates in many organs and organ systems, including the skin, muscles, respiratory, circulatory and nervous sys-tems. In contrast, its body-design resembles that of vetuli-colians, and the presence of a 搕ransitional?nervous system with both dorsal and ventral nerve cords suggests an affinity with living hemichordates. On the basis of these and other recent findings of fossil deuterostomes, a five-step hypothesis for vertebrate origin is proposed, intended to bridge the long- standing gap between protostomes and vertebrates. Four of the five steps accord with established ideas current in modern evolutionary zoology. Evidence for the first step is obtainable only from fossils, and specifically from fossils found from South china, hence the crucial importance of S. china sites for our understanding of early vertebrate origins and evolution. Accordingly, South china is suggested as the oldest-known birthplace of the whole vertebrates.

关键词：脊椎动物动物起源寒武纪中国南部地区

Fault System,Deformation Style and Development Mechanism of the Bachu Uplift,Tarim Basin

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Journal of Earth Science 2012年第4期23卷 529-541页

作者：佟殿君张俊霞阳怀忠胡德胜任建业 Key Laboratory of Tectonics and Petroleum Resources of Ministry of Education China University of Geosciences school of Economics and Management China University of Geosciences beijing Research Institute CNOOC Zhanjiang Branch CNOOC Structral Research Center of Oil&Gas Bearing Basin Ministry of EducationChina University of Geosciences

The Bachu （巴楚） uplift is one of the most active tectonic regions nowadays in the Tarim basin, which is also a faulted block uplift that was intensively active during the Cenozoic. This study was based primarily on the geological structure interpretation of seismic profiles, applying the theories and methods of basin dynamics, structural analysis and tectono-stratigraphic analysis, the geometry and kinematics features of the fault systems in the Bachn uplift were analyzed in detail. Our study shows that each fault belt is mainly characterized by compression and overthrusting, most of the faults initiated and activated during the Mid-Late Himalayan period, and that the general structural styles of the Bachu uplift were basement-involved pop-up thrust faulted block uplift, of which the southern margin was covered by the large-scale decollement fault system. The basement-involved structures widely developed in the higher position of the basement uplift, while decollement fault system developed mainly at the position with gypsum mudstone. The evolution process of Bachu uplift included back-bulge slope of the peripheral foreland basin in Mid-Late Caledonian, forebulge in HercynianYanshanian and the latest compressional faulted block uplift in Mid-Late Himalayan. Meanwhile,the study also suggests that the formation, reconstruction and stabilization of the uplift were controlled by the development and evolution of fault systems clearly. In the early forebulge stage, it was mainly presented as flexural deformation without the developing of thrust faults in the Bachu area; to the late stage, under the influence of violent lateral compression deformation, the faulted block uplift formed finally.

关键词： fault system structural style structural evolution Bachu uplift Tarim basin.

Influence of mild hypothermia on vascular endothelial growth factor and infarct volume in brain tissues after cerebral ischemia in rats

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Neural Regeneration Research 2006年第9期1卷 847-849页

作者： Fei Ye1, Gangming Xi1, Biyong Qin1, Shifeng Wang1, Chengyan Li2.1Department of Neurology, People’s Hospital of Yunyang Medical College, Shiyan 442.00, Hubei Province, china 2.epartment of Neurology, Renmin Hospital of Wuhan University, Wuhan 43.060, Hubei Province, china Department of Neurology People's Hospital Yunyang Medical College Shiyan 442000 Hubei Province China Department of Neurology Renmin Hospital Wuhan University Wuhan 430060 Hubei Province China

BACKGROUND: It has been demonstrated that mild hypothermia has obvious protective effect on both whole and local cerebral ischemia. However, the definite mechanism is still unclear for the brain protection of mild hypothermia on cerebral edema, inhibiting inflammatory reaction, stabilizing blood brain barrier, etc. OBJECTIVE: To investigate the effect of mild hypothermia on the expression of vascular endothelial growth factor and the infarct volume after cerebral ischemia in rats, and analyze the brain protective mechanism of mild hypothermia. DESIGN: A randomized grouping and controlled animal trial. SETTING: Department of Neurology, People’s Hospital of Yunyang Medical College. MATERIALS: Twenty adult male SD rats of clean degree, weighing (2.0±3.) g, were provided by the animal experimental center, school of Medicine, Wuhan University. The kits for SP immunohistochemistry were purchased from beijing Zhongshan Golden Bridge Biotechnology Co., Ltd. METHODS: The experiments were carried out in the laboratory of Department of Neurology, Renmen Hospital of Wuhan University from May to July 2.05. ① The 2. rats were divided randomly into normal temperature group (n =10) and mild hypothermia group (n =10). Models of permanent middle cerebral artery occlusion were established with modified nylon suture embolization. The rats were assessed with the Longa standards: 0 point for without nerve dysfunction; 1 for mild neurological deficit (fore claws could no extend completely); 2.for moderate neurological deficit (circling towards the affected side); 3.for severe neurological deficit (tilting towards the affected side); 4 for coma and unconscious; 1-3.points represented that models were successfully established. The rats of the normal temperature group were fed at room temperature, and those in the mild hypothermia group were induced by hypothermia from 2.hours postoperatively, and the rectal temperature was kept at 3.-3. ℃ for 72.hours. ② Measurement of infarct volume: All t

关键词： infarct neurological purchased hemisphere protective minutes Biotechnology stained occlusion Wuhan

A Discrete-time AILC for Systems with Non-parametric Uncertainties

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A Discrete-time AILC for Systems with Non-parametric Uncerta...

Giant Volume Magnetostriction Caused by Itinerant Electron Metamagnetic Transition and Pronounced Invar Effects in La(Fe_xSi_(1-x))_(13. Compounds

第二十九届中国控制会议

作者： CHI Ronghu1,HOU Zhongsheng2.JIN Shangtai2.1.school of Automation&Electrical Engineering,Qingdao University of Science&Technology,Qingdao 2.6042.P.R.china2.Advanced Control Systems Lab,school of Electronics and Information Engineering,beijing Jiaotong University,beijing 100044,P.R.china

In this paper,a discrete adaptive ILC is presented for a time-varying nonlinear system with nonparametric uncertainties.A novel estimation of nonparametric uncertainties is constructed just using the past I/O data,and the uncertainties are completely compensated such that the output tracking error is only affected by external *** a main contribution of this paper,all the discussions are done with the random initial condition and the iteration-varying target *** the rigorous mathematical analysis and the simulation results illustrate the correctness and effectiveness of the proposed approach.

关键词： Adaptive Iterative learning control Non-parametric Uncertainties Random Initial Condition Iteration-varying Trajectories Discrete-time Systems

来源： cnki会议评论

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Journal of Materials Science & Technology 2000年第2期16卷 167-171页

作者： K.Fukamichi and A.Fujita (Department of Materials Science, graduate school of Engineering, Tohoku University, Aoba-yama 02. Sendai 980-8579, Japan) Department of Materials Science Graduate School of Engineering Tohoku University Aoba-yama 02 Sendai 980-8579 Japan

A first-order itinerant electron metamagnetic (IEM) transition above the Curie temperature Tc for ferromagnetic La(Fe_xSi_1-x)13.compounds has been confirmed by applying magnetic field. The volume change just above T_C for x=0.88 is huge of about 1.5%, which is caused by a large magnetic moment induced by the IEM transition. These compounds have a possibility for practical applications as giant magnetostrictive materials. Pronounced Invar effects bring about a negative thermal expansion below TC, closely correlated with the negative mode-mode coupling among spin fluctuations.

关键词： Compounds Fe_xSi Giant Volume Magnetostriction Caused by Itinerant Electron Metamagnetic Transition and Pronounced Invar Effects in La

Digital Rights Management：Model,Technology and Application

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china Communications 2017年第6期14卷 156-167页

作者： Zhaofeng Ma school of Cyberspace Security Beijing University of Posts and Telecommunications Beijing 100876 China

with rapid achievement of current information technology and computing ability and applications,much more digital content such as films,cartoons,design drawings,office documents and software source codes are produced in daily work,however to protect the content being copying,shared or deliberately stolen by inside or outside,digital rights management(DRM) became more and more important for digital content *** this paper,we studied various DRM model,technology and application,and first proposed DRM Security Infrastructure(DSI),in which we defined encryption,hash,signature algorithm,watermarking algorithms,authentication,usage control,trusted counter,conditional trace,secure payment,and based on the DSI we then proposed a whole classification approach and architecture of all kinds of DRMs,in which we proposed 6 typical classes of copyrights and content protection DRMs architecture:(1) Software-oriented DRM,(2. e Book-oriented DRM,(3. Video-oriented DRM,(4) Image-Oriented DRM(5) Unstructured data oriented DRM,(6) Text-oriented *** on the above DSI,we then proposed a dynamic DRM model selection method for various DRM application,which can be adapted dynamically for different technology of different applications,which can provide awhole solution for variant DRM development in a rapid and customized *** proposed DRM method,technology and application in this paper provided a common,flexible and extendable solution for variant DRM scenes,and can support rapid and customized ***,we proposed an opinion that the future life will enter into a new era that the content usage and consumption will not again adopt DRM technology rather than with law,liberty and morality.

关键词： digital rights management drm security infrastructure encryption watermark usage control drm-free

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混沌经济时序非线性动力系统的预测方法研究

系统工程学报 2002年第2期17卷 97-102页

作者：马军海盛昭瀚天津大学管理学院天津300072 南京大学管理科学与工程研究院南京210093

混沌经济时序的预测方法研究是混沌经济非线性动力系统的重要内容 .提出了一种改进的非线性混沌经济模型 ,应用模型的阶数由最小嵌入维数决定的观点 ,给出了相应的模型参数辨识方法 ,并用其确立的混沌模型进行了预测工作 .计算结果表明 ... 详细信息

混沌经济时序的预测方法研究是混沌经济非线性动力系统的重要内容 .提出了一种改进的非线性混沌经济模型 ,应用模型的阶数由最小嵌入维数决定的观点 ,给出了相应的模型参数辨识方法 ,并用其确立的混沌模型进行了预测工作 .计算结果表明 :模型参数辨识方法能迅速地将参数估计值带到多峰目标函数的全局最小值附近 ,然后再采用优化理论能较准确地求出模型的参数 ,用得到的混沌模型对系统进行预测工作。

关键词：混沌经济时序混沌模型参数辨识非线性动力系统预测

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木结构建筑的回归与发展

沈阳大学学报 2004年第6期16卷 81-82页

作者：于群杨晓慧沈阳大学建筑工程学院辽宁沈阳110044 北京中建建筑设计院北京100073

介绍了木结构建筑的环保、节能、高效等特点,对木结构的发展现状进行了分析,认为木结构建筑在我国的发展前景十分广阔·

关键词：木结构建筑木结构特点木结构发展趋势

H∞ Optimal Control for Delay System

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H∞ Optimal Control for Delay System