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FAST W TRANSFORM——ALGORITHMS AND PROGRAMS

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Science China Mathematics 1989年第3期32卷 338-350页

作者：王中德 Beijing University of Posts & Telecommunications present address:Beijing University of Posts & Telecommunications.

The W transform is an approach to spectrum analysis in real domain. There are fourcommonly used types of the discrete W transform (DWT), all of which may be appliedto digital signal processing. In this paper, new fast algorithms for computing the fourtypes of the DWT are introduced. These algorithms are simple in structure and moreefficient than any other algorithms for the DWT. FORTRAN subroutines to realize thesealgorithms have been provided.

关键词： fast algorithm W transform spectral analysis.

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SINGLE CRYSTAL HARDENING——MECHANISMS AND DESCRIPTION

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Acta Mechanica Sinica 1995年第2期11卷 162-167页

作者：孙守光黄克智 present address: Department of Mechanical Engineering Northern Jiaotong UniversityBeijing China 100044 Department of Engineering Mechanics Tsinghua University Beijing China 100084

Various work hardening mechanisms, on the basis of their characteristics, are classified into two categories: the pile-up hardening and the tangle hardening. Together with a discussion about the experimental investigations of work hardening, the descriptions for those two basic hardening mechanisms are suggested, respectively. Combining these descriptions, a new single crystal hardening law is proposed, which can be used to describe work hardening, particularly the cyclic hardening of a crystal grain in a polycrystalline material. Furthermore, some relevant discussion on the new single crystal hardening law is also made in this paper.

关键词： CRYSTAL PLASTICITY SINGLE CRYSTAL HARDENING CYCLIC HARDENING

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Identification of Early Nuclear Target Genes of Plastidial Redox Signals that Trigger the Long- Term Response of Arabidopsis to Light Quality Sh∽ts

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Molecular Plant 2015年第8期8卷 1237-1252页

作者： Lars Dietzel Christine Glaeer Monique Liebers Stefan Hiekel Florence Courtois Olaf Czarneckit Hagen Schlicke Yan Zubo Thomas Borner Klaus Mayer Bernhard Grimm Thomas Pfannschmidt Department of Plant Physiology Institute of General Botany and Plant Physiology Friedrich-Schiller-University of Jena Domburger Strasse 159 07743 JenaGermany MIPS/IBI Helmholtz Zentrum MGnchen German Research Center for Environmental Health (GmbH) Ingolst~dter Landstrasse 1 85764 Neuherberg Germany Institute of Biology/Plant Physiology Humboldt-University Berlin Philippstrasse 13 Building 12 10115 Berlin Germany Institute of Biology Genetics Humboldt-University Berlin Chausseestrasse 117 10115 Berlin Germany present address: Institut fer Molekulare Biowissenschaften Pflanzliche Zellphysiologie Max-von-Laue-Strasse 9 Biozentrum Goethe-Universit~t Frankfurt 60438Frankfurt am Main Germany present address: Zentrum fur Molekulare Biologie an der Universitat zu Heidelberg (ZMBH) Im Neuenheimer Feld 282 69120 Heidelberg Germany present address: Universite Grenoble-Alpes F-38000 Grenoble France present address: CNRS UMR5168 F-38054 Grenoble France present address: CEA iRTSV Laboratoire de Physiologie Cellulaire & Vgetale F-38054 Grenoble France present address: INRA USC1359 F-38054 Grenoble France present address: Plant Reproductive Biology Group Department of Physiology and Ceil-Biology Leibniz Institute of Rant Genetics and Crop Plant Research (IPK)OT Gatersleben Corrensstrasse 3 D-06466 Stadt Seeland Germany present address: KWS Saat AG Grimsehlstrasse 31 37555 Einbeck Germany present address: Dartmouth College Department of Biological Sciences Ufe Sciences Center 78 College Street Hanover NH 03755 USA

Natural illumination conditions are highly variable and because of their sessile life style, plants are forced to acclimate to them at the cellular and molecular level. Changes in light intensity or quality induce changes in the reduction/oxidation （redox） state of the photosynthetic electron chain that acts as a trigger for compen- satory acclimation responses comprising functional and structural adjustments of photosynthesis and metabolism. Such responses include redox-controlled changes in plant gene expression in the nucleus and organelles. Here we describe a strategy for the identification of early redox-regulated genes （ERGs） in the nucleus of the model organism Arabidopsis thaliana that respond significantly 30 or 60 min after the generation of a reduction signal in the photosynthetic electron transport chain. By comparing the response of wild-type plants with that of the acclimation mutant stn7, we could specifically identify ERGs. The results reveal a significant impact of chloroplast redox signals on distinct nuclear gene groups including genes for the mitochondrial electron transport chain, tetrapyrrole biosynthesis, carbohydrate metabolism, and signaling lipid synthesis. These expression profiles are clearly different from those observed in response to the reduction of photosynthetic electron transport by high light treatments. Thus, the ERGs identified are unique to redox imbalances in photosynthetic electron transport and were then used for analyzing potential redox-responsive cis-elements, trans-factors, and chromosomal regulatory hot spots. The data identify a novel redox-responsive element and indicate extensive redox control at transcriptional and chromosomal levels that point to an unprecedented impact of redox signals on epigenetic processes.

关键词： plastidial redox signaling,early redox-regulated gene Arabidopsis thaliana Molecular Plant

THE DELAY OF TRANSITION OF A LAMINAR BOUNDARY LAYER OVER COMPLIANT WALL

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Acta Mechanica Sinica 1990年第1期6卷 15-21页

作者： Li Wanping Zhou Heng Tianjin University present address:Department of Mechanics Huazhong University of Science and TechnologyWuhan 430074

In a previous paper, a method has been developed to study the stability characteristics of laminar boundary layers over compliant walls. In this paper, the effect of double layered compliant wall and Kramer type compliant wall on delaying the transition is investigated, and it is shown that there does exist the possibility to de- lay the transition by applying such compliant walls.

关键词： transition compliant wall stability

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Blocking the Metabolism of Starch Breakdown Products in Arabidopsis Leaves Triggers Chloroplast Degradation

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Molecular Plant 2009年第6期2卷 1233-1246页

作者： Michaela Stettler Simona Eicke Tabea Mettler Gaelle Messerli Stefan Hortensteiner Samuel C. Zeeman Department of Biology ETH Zurich CH-8092 Zurich Switzerland Institute of Plant Biology University of Zurich CH-8008 Zurich Switzerland present address: Max Planck Institute for Molecular Plant Physiology Potsdam-Golm 14476 Germany present address: Johnson & Johnson Medical CH-8957 Spreitenbach Switzerland

In most plants, a large fraction of photo-assimilated carbon is stored in the chloroplasts during the day as starch and remobilized during the subsequent night to support metabolism. Mutations blocking either starch synthesis or starch breakdown in Arabidopsis thaliana reduce plant growth. Maltose is the major product of starch breakdown exported from the chloroplast at night. The maltose excess 1 mutant （mex1）, which lacks the chloroplast envelope maltose transporter, accumulates high levels of maltose and starch in chloroplasts and develops a distinctive but previously unexplained chlorotic phenotype as leaves mature. The introduction of additional mutations that prevent starch synthesis, or that block maltose production from starch, also prevent chlorosis of mex1. In contrast, introduction of mutations in disproportionating enzyme （DPE1） results in the accumulation of maltotriose in addition to maltose, and greatly increases chlorosis. These data suggest a link between maltose accumulation and chloroplast homeostasis. Microscopic analyses show that the mesophyll cells in chlorotic mex1 leaves have fewer than half the number of chloroplasts than wild-type cells. Transmission electron microscopy reveals autophagy-like chloroplast degradation in both mex1 and the dpe1/mex1 double mutant. Microarray analyses reveal substantial reprogramming of metabolic and cellular processes, suggesting that organellar protein turnover is increased in mex1, though leaf senescence and senescence-related chlorophyll catabolism are not induced. We propose that the accumulation of maltose and malto-oligosaccharides causes chloroplast dysfunction, which may by signaled via a form of retrograde signaling and trigger chloroplast degradation.

关键词： Carbohydrate metabolism photosynthesis senescence chloroplast biology Arabidopsis autophagy.

Autoionizing Process of the Double Rydberg State

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Chinese Physics Letters 1995年第12期12卷 713-716页

作者： XU Chengbin XU Xiangyuan HUANG Wen XUE Ping ZHAO Runchuan ZHU Cheng CHEN Dieyan Department of Modern Applied Physics Tsinghua UniversityBeijing 100084 present address:Institute of Physics Academia SinicaBeijing 100080

Using five-laser resonance excitation and double time-of-flight spectroscopy,the double Rydberg states NLnl(N≤66;n≤85;L,1<4)of Ca have been *** distribution of Ca^(+)Rydberg states,which is from the autoionization o... 详细信息

关键词： Rydberg double excitation

Sequence-Independent Identification of Active LTR Retrotransposons in Arabidopsis

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Molecular Plant 2018年第3期11卷 508-511页

作者： Jayne,Griffiths Marco,Catoni Mayumi,Iwasaki Jerzy,Paszkowski The Sainsbury Laboratory University of Cambridge Cambridge UK [∗]Corresponding author present address: University of Geneva Geneva Switzerland

Dear Editor,LTR retrotransposons （LTR-TEs） are mobile genetic elements that often comprise a large portion of the host genome and are particularly abundant in genomes of plants （Lisch, 2013）. They transpose through an RNA transcript that is reverse transcribed to an extrachromosomal DNA （ecDNA） of the original element that can insert at a new genomic location （Wicker et al., 2007）.

关键词： Arabidopsis LTR 鉴定人染色体 DNA RNA 元素植物

Transcriptional, post-transcriptional and post-translational regulations of gene expression during leaf polarity formation

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Cell Research 2007年第6期17卷 512-519页

作者： Lin Xu Li YangHai Huang National Laboratory of Plant Molecular Genetics, Shanghai Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, 300 Fenglin Road, Shanghai 200032, China National Laboratory of Plant Molecular Genetics Shanghai Institute of Plant Physiology and Ecology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Shanghai China present address: IBMP CNRS Universite Louis Pasteur 67084 Strasbourg France present address: Department of Biology University of Pennsylvania Philadelphia PA 19104 USA

Leaf morphogenesis requires the establishment of adaxial-abaxial polarity after primordium initiation from the shootapical meristem (SAM). Several families of transcription factors are known to play critical roles in promoting adaxial orabaxial leaf fate. Recently, post-transcriptional gene silencing pathways have been shown to regulate the establishmentof leaf polarity, providing novel and exciting insights into leaf development. For example, microRNAs (miR165/166)and a trans-acting siRNA (TAS3-derived tasiR-ARF) have been shown to repress the expression of several key transcrip-tion factor genes. In addition, yet another level of regulation, post-translational regulation, has been revealed recently bystudies on the role of the 26S proteasome in leaf polarity. Although our understanding regarding the molecular mecha-nisms underlying establishment of adaxial-abaxial polarity has greatly improved, there is still much that remains *** review aims to discuss recent progress, as well as the remaining questions, regarding the molecular mechanismsunderlying leaf polarity formation.

关键词： Arabidopsis leaf development polarity formation

Contactless probing of the intrinsic carrier transport single-walled carbon nanotubes

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Nano Research 2014年第11期7卷 1623-1630页

作者： Yize Stephanie Li Jun Ge Jinhua Cai Jie Zhang Wei Lu Jia Liu Liwei Chen Suzhou Institute of Nano-Tech and Nono-Bionics Chinese Academy of Sciences Suzhou Jiongsu 215123 Chino present address: Department of Materials Science and Engineering University of Wisconsin-Madison Madison W153 706 USA present address: Molecular Foundry Lawrence Berkeley National Laboratory Berkeley CA 94720 USA

Intrinsic carrier transport properties of single-walled carbon nanotubes have been probed by two parallel methods on the same individual tubes： The contactless dielectric force microscopy （DFM） technique and the conventional field-effect transistor （FET） method. The dielectric responses of SWNTs are strongly correlated with electronic transport of the corresponding FETs. The DC bias voltage in DFM plays a role analogous to the gate voltage in FET. A microscopic model based on the general continuity equation and numerical simulation is built to reveal the link between intrinsic properties such as carrier concentration and mobility and the macroscopic observable, i.e. dielectric responses, in DFM experiments. Local transport barriers in nanotubes, which influence the device transport behaviors, are also detected with nanometer scale resolution.

关键词： single-walled carbon nanotubes electronic transport dielectric force microscopy field-effect transistor carrier density carrier mobility