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Whole fossil plants of Ephedra and their implications on the morphology,ecology and evolution of Ephedraceae (Gnetales)

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Chinese Science Bulletin 2010年第15期55卷 1511-1519页

作者： WANG Xin 1,2.& ZHENG ShaoLin 3 1 nanjing institute of Geology and Palaeontology,Chinese Academy of Sciences,nanjing 2.0008,china 2.Fairy Lake Botanical Garden,Shenzhen 518004,china 3 Shenyang institute of Geology and Mineral Resources,Shenyang 110034,china nanjing institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing China Fairy Lake Botanical Garden Shenzhen China Shenyang institute of Geology and Mineral Resources Shenyang China

Although there are many reports of fossil Ephedraceae,whole plant fossil record remains *** to a lack of trust on partially preserved fossil materials,scholars working on molecular clock proposed a recent origin of Ephedra and cast doubt on the earlier origin time of *** better the understanding on this interesting group,here we report whole plants of Ephedra hongtaoi ***.(Ephedraceae,Gnetales) from the Yixian Formation (Early Cretaceous) in western Liaoning,*** whole plants of Ephedra demonstrate clearly the characters of Ephedra,including shrubby growth habit,decussate branching pattern,and terminal ovuliferous unit with micropylar *** whole-plant preservation of the fossils provides more convincing fossil evidence of Early Cretaceous Ephedra,helps to resolve the controversy over the origin time of Ephedra,and sheds light on the whole plant morphology,growth habit,ecology and evolution of Ephedraceae.

关键词：化石植物生态学麻黄形态学进化材料保存早白垩世生长习性

An iterative wavefront sensing algorithm for high-contrast imaging systems

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Research in Astronomy and Astrophysics 2011年第2期11卷 198-204页

作者： Jiang-Pei Dou 1,2.De-Qing Ren 1,2.3 and Yong-Tian Zhu 1,2.1 National Astronomical Observatories/nanjing institute of Astronomical Optics & Technology,Chinese Academy of Sciences,nanjing 2.0042.china 2.Key Laboratory of Astronomical Optics & Technology,nanjing institute of Astronomical Optics & Technology,Chinese Academy of Sciences,nanjing 2.0042.china 3 Physics & Astronomy Department,California State University Northridge,18111 Nordhoff Street,Northridge,California 91330-82.8,USA National Astronomical Observatories / nanjing institute of Astronomical Optics & Technology Chinese Academy of Sciences Nanjing 210042 China Key Laboratory of Astronomical Optics & Technology Nanjing Institute of Astronomical Optics & Technology Chinese Academy of Sciences Nanjing 210042 China Physics & Astronomy Department California State University Northridge 18111 Nordhoff Street Northridge California 91330-8268 USA

Wavefront sensing from multiple focal plane images is a promising technique for high-contrast imaging ***,the wavefront error of an optics system can be properly reconstructed only when it is very *** paper presents an iterative optimization algorithm for the direct measurement of large static wavefront errors from only one focal plane *** first measure the intensity of the pupil image to get the pupil function of the system and acquire the aberrated image on the focal plane with a phase error that will be *** we induce a dynamic phase on the tested pupil function and calculate the associated intensity of the reconstructed image on the focal *** algorithm will then try to minimize the intensity difference between the reconstructed image and the aberrated test image in the focal plane,where the induced phase is a variable of the optimization *** simulation shows that the wavefront of an optical system can theoretically be reconstructed with high precision,which indicates that such an iterative algorithm may be an effective way to perform wavefront sensing for high-contrast imaging systems.

关键词： techniques: image processing -- methods: numerical -- planetarysystems

Linear beamformer schemes with simple relay selection in MIMO relay networks

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The Journal of china Universities of Posts and Telecommunications 2008年第4期15卷 24-29+39页

作者： MENG Qing-min 1,2. PAN Su1, ZHENG Bao-yu1, ZHU Hong-bo1, YOU Xiao-hu2.1. Jiangsu Key Laboratory of Wireless Communications and institute of Signal Processing and Transmission, nanjing University of Posts and Telecommunications, nanjing 2.0003, china 2. National Mobile Communications Research Lab, Southeast University, nanjing 2.0096, china Jiangsu Key Laboratory of Wireless Communications and institute of Signal Processing and Transmission Nanjing University of Posts and Telecommunications Nanjing 210003 China National Mobile Communications Research Lab Southeast University Nanjing 210096 China

This article considers a wireless multi-hop/mesh network where single multi-antenna source-destination pair communicates through a selected relay subset using simple relay selection under the constraint of fixed relay’s number. Compared with random selection, the simple relay selection can yield certain capacity advantages while linear zero-forcing (ZF) receiver and linear beamformer are considered at the relay. For match-filter (MF) beamformer and amplified-and-forward (AF) beamformer with a fixed number of relays, the capacities are given. Furthermore, we extend the simple selection methods to the relaying scheme with orthogonal-triangular (QR) beamformer and investigate these linear beamformer schemes over spatially correlated multi-input multi-output (MIMO) links for both the backward and forward channel over the two-hop MIMO relay networks.

关键词： wireless mesh networks multi-hop relaying capacity beamformer

A Feedback-Based Web Search Engine

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Wuhan University Journal of Natural Sciences 2004年第5期9卷 561-568页

作者： ZHANG Wei-feng 1,2.3 , XU Bao-wen 2.3,4 , ZHOU Xiao-yu 2.3,4 1. Department of Computer Science and Engineering, nanjing University of Posts and Telecommunications, nanjing 2.0003, Jiangsu, {2. 2. Department of Computer Science and Engineering, Southeast University, nanjing 2.0096, Jiangsu, {2. 3. Jiangsu institute of Software Quality, nanjing 2.0096 Jiangsu, {2. 4. The State Key Laboratory of Software Engineering, Wuhan University, Wuhan 430072. Hubei, {2. Department of Computer Science and Engineering Nanjing University of Posts and Telecommunications Nanjing Jiangsu China Department of Computer Science and Engineering Southeast University Najing Jiangsu China Jiangsu institute of Software Quality Nanjing Jiangsu China The State Key Laboratory of Software Engineering Wuhan University Wuhan Hubei China

Web search engines are very useful information service tools in the Internet. The current web search engines produce search results relating to the search terms and the actual information collected by them. Since the selections of the search results cannot affect the future ones, they may not cover most people’s interests. In this paper, feedback information produced by the user’s accessing lists will be represented by the rough set and can reconstruct the query string and influence the search results. And thus the search engines can provide self-adaptability. Key words WWW - search engine - query reconstruction - feedback CLC number TP 311. 135.4 Foundation item: Supported by the National Natural Science Fundation of china (60373066). National Grand Fundamental Research 973 Program of china (2.02.B312.0). Opening Foundation of State Key Laboratory of Software Engineering in Wuhan University, Opening Foundation of Jiangsu Key Laboratory of Computer Information Processing Technology in Soochow UniversityBiography: ZHANG Wei-feng (1975-), male, Ph.D. research direction: artificial intelligence, search engine, data mining, network language.

关键词： WWW search engine query reconstruction feedback

Temporal-spatial variations of euphotic depth of typical lake regions in Lake Taihu and its ecological environmental significance

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Science china Earth Sciences 2006年第4期49卷 431-442页

作者： ZHANG Yunlin1, 2. QIN Boqiang1, HU Weiping1, WANG Sumin1, CHEN Yuwei1 & CHEN Weimin1 1. nanjing institute of Geography & Limnology, Chinese Academy of Sciences, nanjing 2.0008, china 2. Graduate School of the Chinese Academy of Sciences, Beijing 100039, china nanjing institute of Geography & Limnology Chinese Academy of Sciences Nanjing China Graduate School of the Chinese Academy of Sciences Beijing China

By using the data of underwater irradiance measured in the different lakeregions of Lake Taihu during 1998—2.04 and total suspended solids (TSS), wind speeds of the total13 stations in typical lake regions during 1993—2.03, this paper analyzes the factors ofinfluencing on PAR (pho-tosynthetically available radiation) attenuation, euphotic depth, andpresents the temporal and spatial variations of euphotic depth of typical lake regions in LakeTaihu, and the spectral distributions of euphotic depth at station 2. The results show that theconcentration of TSS is the most important factor impacting PAR attenuation, followed by chlorophylla; chromophoric dissolved organic matter (CDOM) has little impact on the PAR euphotic depth. During1993—2.03, the mean yearly PAR euphotic depths of the typical lake regions ranged from 1.04 to1.95 m with a mean value of 1.35±0.2. m. The PAR euphotic depth fell into 3 spatial zone types:Type Ⅰ, the lowest, including the lake center and the inflows of rivers; Type Ⅱ, intermediate,including Meiliang Bay, Wulihu Lake and Gonghu Bay; Type Ⅲ, the greatest, including the East LakeTaihu; corresponding mean depths were approximately 1.1, 1.4, 2.0 m, respectively. The seasonalvariations of euphotic depths were not quite the same in different lake regions. In the lake center,the mean values of PAR euphotic depth in summer and autumn were significantly greater than those inwinter and spring; in the Meiliang Bay, winter means were significantly greater than in the otherthree seasons; in the East Lake Taihu, winter means were significantly less than in the other threeseasons. However, no distinct seasonal change was recorded in the Wulihu Lake, Gonghu Bay and theinflows of rivers. The spectral distributions of euphotic depth present a minimal value at the bluelight wave band of 400 nm, and a peak at the green light wave band of around 580 nm. In 1998 and1999, based on the seasonal many-day continuous measurements, the PAR euphotic depths at station 2.

关键词： lake taihu euphotic depth diffuse attenuation coefficient total suspendedsolid ecological

Dendrite crystal morphology evolution mechanism of β-BaB_2._4 crystal

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Science china(Technological Sciences) 2009年第6期52卷 1703-1706页

作者： HE ChongJun1,ZHONG WeiZhuo2.& LIU YouWen1 1 College of Science,nanjing University of Aeronautics and Astronautics,nanjing 2.0016,{2. 2.Shanghai institute of Ceramics,Chinese Academy of Sciences,Shanghai 2.1800,{2. College of Science Nanjing University of Aeronautics and Astronautics Nanjing China Shanghai institute of Ceramics Chinese Academy of Sciences Shanghai China

Existence of [B3-O6]3- hexagonal ring growth unit in melt solution of β-BaB2.4 crystal was proved by the results of high temperature Raman measurements.A morphology evolution process of β-BaB2.4 crys-tal was observed by a high temperature in-situ observation *** crystal morphology varied with the supersaturation of growth melt *** mechanism of β-BaB2.4 crystal morphology evolution was analyzed through the growth unit model.

关键词： crystal morphology Growth unit model:BBO crystal Raman measurement

Environmental archaeology of the Dachang region in the Daning Valley,the Three Gorges reservoir region of the Yangtze River,china

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Chinese Science Bulletin 2008年第S1期53卷 140-152页

作者： ZHANG Yun 1 &ZHU Cheng 2.1 State Key Laboratory of Vegetation and Environmental Change,institute of Botany,Chinese Academy of Sciences,Beijing 100093, china 2.School of Geographic and Oceanographic Sciences,{2. University,{2. 2.0093,china State Key Laboratory of Vegetation and Environmental Change Institute of Botany Chinese Academy of Sciences Beijing China School of Geographic and Oceanographic Sciences Nanjing University Nanjing China

Environmental archaeology of archaeological sites on both sides of the Dachang section in the Daning River,the Three Gorges of the Yangtze River,shows that riverbed evolution has a great influence on the distribution of archaeological sites during the prehistorical and historical period,and it restricts human activity and the development of ancient *** investigation,dating data,paleocurrent analysis of 100 gravels on the riverbed and archaeological excavation reveal that the riverbed of the Dachang section developed in the Shuangyantang region during the early stage,after about 30 kaBP it shifted westward gradually and reached the present *** with the westward shift,the focus of ancient culture changed for several *** the Western Zhou Dynasty's period,the east riverbank of the Daning River was the main residential *** the Han Dynasty,along with the westward shift,the living space of ancient people was no longer confined to the east riverbank and the focus of culture moved *** the Zhangjiawan site became the main dwelling *** the late Han Dynasty, the villages were flooded and the ancients had to immigrate to a high *** of the Han and the Jin Dynasties outcropped on the flood plain of the east bank because their surface sediments were eroded by several flood events and the westward shift of the riverbed.

关键词： the Daning River environmental archaeology the Shuangyantang site the Zhangjiawan site tombs of the Han and the Jin Dynasties

Achievable bit rates of cognitive user with Vandermonde precoder in cognitive radio network

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Science china(Information Sciences) 2011年第7期54卷 1471-1480页

作者： XU XiaoRong 1,ZHANG JianWu 1 & ZHENG BaoYu 2.1 College of Telecommunication Engineering,Hangzhou Dianzi University,Hangzhou 310018,china 2.institute of Signal Processing and Transmission,{2. University of Posts and Telecommunications,{2. 2.0003,china College of Telecommunication Engineering Hangzhou Dianzi University Hangzhou China institute of Signal Processing and Transmission Nanjing University of Posts and Telecommunications Nanjing China

In cognitive radio network (CRN) where primary user (PU) and secondary user (SU) wish to communicate with their corresponding receivers simultaneously over frequency selective fading channels,the interference between PU and SU should be eliminated in order to realize spectrum *** division multiple access (PDMA) that implements Vandermonde precoder in cognitive orthogonal frequency division multiplexing (OFDM) is proposed,which benefits from the frequency selectivity of the cognitive channel to form a frequency *** precoder enables SUs to achieve higher bit rate with optimal power allocation strategy under the condition of PU interference *** and simulation results are presented to prove theoretical *** is shown that,achievable bit rates (ABR) of SU could be achieved with optimal power allocation scheme in ***,it is also verified that,with Vandermonde precoder to form PDMA,SU’s signal-to-noise ratio (SNR) and the target rate of PU could impact the ABR of SU significantly in CRN.

关键词： achievable bit rates (ABR) Vandermonde precoder precoder division multiple access (PDMA) optimal power allocation cognitive radio network (CRN)

Effect of bowel rehabilitative therapy on structural adaptation of remnant small intestine: animal experiment

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World Journal of Gastroenterology 2001年第1期7卷 66-73页

作者： Xin Zhou1 Yuan Xin Li2.Ning Li2.Jie Shou Li2.1Department of General Surgery, Medical School, nanjing University, nanjing 2.0093. Jiangsu Province. {2.2.esearch institute of General Hospital. Chinese PLA General Hospital of nanjing Military Area, nanjing 2.0002. Jiangsu Province. {2. Research institute of General Surgery Chinese PLA General Hospital of Nanjing Military Area 305 East Zhongshan Road Nanjing 210002 Jiangsu Province China.

AIM: To investigate the individual and the combined effects of glutamine, dietary fiber, and growth hormone on the structural adaptation of the remnant small bowel. METHODS: Forty-two adult male Sprague-Dawley rats underwent 85% mid-small bowel resection and received total parenteral nutrition (TPN) support during the first three postoperational *** the 4th postoperational day, animals were randomly assigned to receive 7 different treatments for 8 days: TPNcon group, receiving TPN and enteral 2. g x L(-1) glycine perfusion; TPN+Gln group, receiving TPN and enteral 2. g x L(-1) glutamine perfusion; ENcon group, receiving enteral nutrition (EN) fortified with 2. g x L(-1) glycine; EN+Gln group, enteral nutrition fortified with 2. g x L(-1) glutamine; EN+Fib group, enteral nutrition and 2.g x d(-1) oral soybean fiber; EN+GH group, enteral nutrition and subcutaneous growth hormone (GH) (0.3 IU) injection twice daily; and ENint group, glutamine-enriched EN, oral soybean fiber, and subcutaneous GH injection. RESULTS: Enteral glutamine perfusion during TPN increased the small intestinal villus height (jejunal villus height 2.0 microm +/- 2. microm in TPNcon vs 330 microm +/- 54 microm in TPN+Gln, ileal villus height 2.0 microm +/- 2. microm in TPNcon vs 330 microm +/- 2. microm in TPN+Gln, P2.microm in TPNcon vs 460 microm +/- 65 microm in TPN+Gln, ileal mucosa thickness 400 microm +/- 2. microm in TPNcon vs 490 microm +/- 11 microm in TPN+Gln,P2.0 g +/- 3.6g in EN+Fib, 2.5.7 g +/- 3.3 g in EN+GH, vs 2.7 g +/- 3.3 g in ENcon, P2.microg x L-(-1) in EN+Fib,12.0 microg x L(-1). 96 microg x L-(-1) in EN +/- GH, vs 62. microg x L(-1).43 microg x L-(-1) in ENcon, P< 0.05),

关键词： Parenteral Nutrition, Total Adaptation, Physiological Animals Body Weight Dietary Fiber Glutamine Glycine Growth Hormone Insulin-Like Growth Factor I Intestinal Mucosa Intestine, Small Male Rats Rats, Sprague-Dawley Recovery of Function Research Support, Non-U.S. Gov't Short Bowel Syndrome