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Function of the iron-binding chelator produced by Coriolus versicolor in lignin biodegradation

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Science China(Life Sciences) 2008年第3期51卷 214-221页

作者： WANG Lu1, YAN WenChao1, CHEN JiaChuan2, HUANG Feng1,2 & GAO PeiJi1 1 state key laboratory of Microbial Technology, Shandong University, Jinan 250100, China 2 Shandong key lab of Pulp and Paper Engineering, Shandong Institute of Light Industry, Jinan 250100, China state key laboratory of Microbial Technology Shandong University Jinan 250100 China Shandong key lab of Pulp Paper Engineering Shandong Institute of Light Industry Jinan 250100 China

An ultrafiltered low-molecular-weight preparation of chelating compounds was isolated from a wood-containing culture of the white-rot basidiomycete Coriolus versicolor. This preparation could chelate Fe3. and reduce Fe3. to Fe2+, demonstrating that the substance may serve as a ferric chelator, oxygen-reducing agent, and redox-cycling molecule, which would include functioning as the electron transport carrier in Fenton reaction. Lignin was treated with the iron-binding chelator and the changes in structure were investigated by 1H-NMR, 13.-NMR, difference spectrum caused by ionization under alkaline conditions and nitrobenzene oxidation. The results indicated that the iron-binding chelator could destroy the β-O-4 bonds in etherified lignin units and insert phenolic hydroxyl groups. The low-molecular-weight chelator secreted by C. versicolor resulted in new phenolic substructures in the lignin polymer, making it susceptible to attack by laccase or manganese peroxidase. Thus, the synergic action of the iron-binding chelator and the lignocellulolytic enzymes made the substrate more acces- sible to degradation.

关键词： Coriolus versicolor lignin degradation iron binding chelator

SOME RESULTS ON GENERALIZED DIFFERENCE SETS

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Journal of systems Science & Complexity 2008年第1期21卷 76-84页

作者： Xiwang CAO School of Mathematical Science, Nanjing University of Aeronautics and Astronautics, Nanjing 210016, China state key lab. of Information Security, Beijing 100049, China. School of Mathematical Science Nanjing University of Aeronautics Astronautics Nanjing 210016 China state key lab. of Information Security Beijing 100049 China

Sequences with ideal correlation functions have important applications in communications such as CDMA, FDMA, etc. It has been shown that difference sets can be used to construct such sequences. The author extends Pott and Bradley＇s method to a much broader case by proposing the concept of generalized difference sets. Some necessary conditions for the existence of generalized difference sets are established by means of some Diophantine equations. The author also provides an algorithm to determine the existence of generalized difference sets in the cyclic group Zv. Some examples are presented to illustrate that our method works.

关键词： Correlation functions diophantine equations generalized difference sets.

Bed Load Transport Rate in Scouring and Armoring Process of Non-uniform Sediment River Bed

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四川大学学报（工程科学版） 2005年第S1期37卷 86-88页

作者： LI Wenping CAO Shuyou LIU Xingnian(state key lab.of Hydraulics and Mountain River Eng.,Sichuan Univ.,Chengdu 610065,China) state key lab. of Hydraulics and Mountain River Eng. Sichuan Univ. Chengdu 610065 China

Flume experiments were carried out to study bed load transport rate during rive bed scouring and ar- moring.A theoretical differential equation linking the transport rate to the probability of incipient motion of non-uniform sediment is *** transport rate is shown to decrease exponentially with time,according to the theory,which is in good agreement with the experiment data.

关键词： bed-load scouring and armoring sediment transport rate

The maximal rates and minimal decoding delay of more general complex orthogonal designs

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Science China(Information Sciences) 2010年第9期53卷 1826-1832页

作者： LI Yuan,KAN HaiBin*,YUAN Chen & MA HuanFei The Shanghai key lab of intelligent Information Processing,School of Computer Science,Fudan University,Shanghai 20043.,China 1. The Shanghai key lab of intelligent Information Processing School of Computer Science Fudan University Shanghai 200433 China

Space-time block codes based on complex orthogonal design have been widely investigated for their remarkable *** this paper,we propose a definition of more general complex orthogonal designs,which permits arbitrary complex factor with unit modulus in each *** prove that the maximal rate is still (m+1)/2m for n = 2m or 2m-1 antennas and minimal delay is also lower-bounded by(2m/(m-1)).Thus,allowing complex factor with unit modulus in each entry will not improve the main performance criterion of space-time block codes.

关键词： space-time block codes complex orthogonal design more general complex orthogonal design maximal rates minimal delays

A fusion algorithm for remote sensing images based on nonsubsampled pyramids and bidimensional empirical decomposition

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Science China(Technological Sciences) 2010年第S1期53卷 196-204页

作者： ZHANG XiaoDong 1,WANG WenBo 2,WANG DiFeng 3.& ZHANG Yu 4 1 state key laboratory of Information Engineering in Surveying,Mapping and Remote Sensing,Wuhan University,Wuhan 43.079,China 2 College of Sciences,Wuhan University of Science and Technology,Wuhan 43.065,China 3.0} key laboratory of Satellite Ocean Environment Dynamics,Second Institute of Oceanography,state Oceanic Administration,Hangzhou 3.0012,China 4 Spatial Information Technology Application Research Institute,Changjiang River Scientific Research Institute,Wuhan 43.010,China Wuhan Univ State Key Lab Informat Engn Surveying Mapping & R Wuhan 430079 Peoples R China Wuhan Univ Sci & Technol Coll Sci Wuhan 430065 Peoples R China state Ocean Adm Inst Oceanog 2 State Key Lab Satellite Ocean Environm Dynam Hangzhou 310012 Zhejiang Peoples R China Changjiang River Sci Res Inst Spatial Informat Technol Applicat Res Inst Wuhan 430010 Peoples R China

In order to improve the quality of remote sensing image fusion,a new method combining nonsubsampled Laplacian pyramid (NLP)and bidimensional empirical mode decomposition(BEMD)is ***,the high resolution panchromatic image (PAN)is decomposed using NLP until the approximate component and the low resolution multispectral image(MS)contain features with a similar ***,the approximation component and the MS are decomposed by BEMD,resulting in a number of bidimensional intrinsic mode functions(BIMF)and a residue *** instantaneous frequency is computed in 4 directions of the *** the positive or negative coefficients in the corresponding position,a weighted algorithm is designed for fusing the high frequency details using the instantaneous frequency and the coefficient absolute value of the BIMFs as fusion *** fused image is then obtained through inverse BEMD and *** results have illustrated the advantage of this method over the IHS,DWT andà-Trous wavelet in both spectral and spatial detail qualities.

关键词： bidimensional empirical mode decomposition nonsubsampled pyramid instantaneous frequency remote sensing image fusion

Latest progress on interactions between VLF/ELF waves and energetic electrons in the inner magnetosphere

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Science China Earth Sciences 2010年第3期53卷 317-326页

作者： XIAO FuLiang1,2, ZONG QiuGang3. SU ZhenPeng4, TIAN Tian3.& ZHENG HuiNan4 1 School of Physics and Electronic Sciences, Changsha University of Science and Technology, Changsha 410004, China 2 state key laboratory of Space Weather, Chinese Academy of Sciences, Beijing 100190, China 3.Institute of Space Physics and Applied Technology, Peking University, Beijing 100871, China 4 CAS key lab for Basic Plasma Science, School of Earth and Space Sciences, University of Science and Technology of China, Hefei 23.026, China 1. School of Physics and Electronic Sciences Changsha University of Science and Technology Changsha 410004 China2. State Key Laboratory of Space Weather Chinese Academy of Sciences Beijing 100190 China3. Institute of Space Physics and Applied Technology Peking University Beijing 100871 China4. CAS Key Lab for Basic Plasma Science School of Earth and Space Sciences University of Science and Technology of China Hefei 230026 China

Interactions between very/extremely low frequency (VLF/ELF) waves and energetic electrons play a fundamental role in dynamics occurring in the inner magnetosphere. Here, we briefly discuss global properties of VLF/ELF waves, along with the variability of the electron radiation belts associated with wave-particle interactions and radial diffusion. We provide cases of electron loss and acceleration as a result of wave-particle interactions primarily due to such waves, and particularly some preliminary results of 3. evolution of phase space density from our currently developing 3. code. We comment on the existing mechanisms responsible for acceleration and loss, and identify several critical issues that need to be addressed. We review latest progress and suggest open questions for future investigation.

关键词： wave-particle interaction VLF/ELF waves energetic electrons acceleration and loss inner magnetosphere

Efficient Cleavage of DNA by the Novel Copper (II) Complex Derived From 2,2'-Pyridil Ligand

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Chinese Chemical Letters 2001年第6期12卷 495-496页

作者： Rui REN1,3. Pin YANG2 1Biotechnology laboratory, Shanxi University, Taiyuan 03.006 2Institute of Molecular Science, Shanxi University, Taiyuan 03.006 3.1} key laboratory of Coordination Chemistry, Nanjing University, Nanjing 210093 Shanxi Univ Biotechnol Lab Taiyuan 030006 Peoples R China Shanxi Univ Inst Mol Sci Taiyuan 030006 Peoples R China Nanjing Univ State Key Lab Coordinat Chem Nanjing 210093 Peoples R China

Copper (II) complex derived from 2, 2'-pyridil ligand has been, demonstrated to cleave efficiently DNA at micromolar concentrations at room temperature and pH 7.25.

关键词： copper (II) complex DNA efficient cleavage

Efficient expression of codon-adapted human acetaldehyde dehydrogenase 2 cDNA with 6×His tag in Pichia pastoris

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Science China(Life Sciences) 2009年第10期52卷 935-941页

作者： ZHAO YuFeng1,2, LEI MingKe2, WU YuanXin2, ZHANG ZiSheng3.& WANG CunWen2 1 state key laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agriculture University, Wuhan 43.070, China 2 key laboratory for Green Chemical Processes of the Ministry of Education, Hubei key lab of Novel Reactor & Green Chemical Technology, School of Chemical Engineering and Pharmacy, Wuhan Institute of Technology, Wuhan 43.074, China 3.Department of Chemical Engineering, University of Ottawa, Ottawa, Canada K1N 6N5 1. state key laboratory of Agricultural Microbiology College of Life Science and Technology Huazhong Agriculture University Wuhan 430070 China 2. key laboratory for Green Chemical Processes of the Ministry of Education Hubei Key Lab of Novel Reactor & Green Chemical Technology School of Chemical Engineering and Pharmacy Wuhan Institute of Technology Wuhan 430074 China 3. Department of Chemical Engineering University of Ottawa Ottawa Canada K1N 6N5

Human mitochondrial acetaldehyde dehydrogenase 2 (ALDH2) catalyzes the oxidation of acetaldehyde to acetic acid. Therefore, ALDH2 has therapeutic potential in detoxification of acetaldehyde. Further-more, ALDH2 catalyzes nitroglycerin to nitrate and 1, 2-glyceryldinitrate during therapy for angina pectoris, myocardial infarction, and heart failure. Large quantities of ALDH2 will be needed for potential clinical practice. In this study, Pichia pastoris was used as a platform for expression of human ALDH2. Based on the ALDH2*1 cDNA sequence, we designed ALDH2 cDNA by choosing the P. pastoris preferred codons and by decreasing the G + C content level. The sequence was synthesized using the overlap extension PCR method. The cDNA and 6×His tags were subcloned into the plasmid pPIC9K. The recombinant protein was expressed in P. pastoris GS115 and purified using Ni2+-Sepharose affinity chromatography. The amount of secreted protein in the culture was 80 mg/L in shake-flask cultivation and 260 mg/L in high-density bioreactor fermentation. Secreted ALDH2 was easily purified from the culture supernatant by using Ni2+-Sepharose affinity chromatography. After purification of the fermentation supernatant, the enzyme had a specific activity of 1.2 U/mg protein. The yield was about 16 mg/L in a shake flask culture of P. pastoris GS115 which contained the original human ALDH2*1 cDNA.

关键词： acetaldehyde dehydrogenase codon optimization overlap extension PCR Pichia pastoris.

Megaripples from the Mesoproterozoic of the Kimberley region,northwestern Australia and its geological implications

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Journal of Palaeogeography 2012年第1期1卷 15-25页

作者： Lan Zhongwu 1,2,3.,Zhong-Qiang Chen 2,4,1.state key laboratory of Lithospheric Evolution,Institute of Geology and Geophysics,Chinese Academy of Sciences,Beijing 100029,China 2.School of Earth and Environment,The University of Western Australia,Australia 3.key lab of Petroleum Resources Research,Institute of Geology and Geophysics,Chinese Academy of Sciences,Beijing 100029,China 4.state key laboratory of Biogeology and Environmental Geology,China University of Geosciences (Wuhan),Wuhan 43.074,China state key laboratory of Lithospheric Evolution Institute of Geology and Geophysics Chinese Academy of Sciences School of Earth and Environment The University of Western Australia key lab of Petroleum Resources Research Institute of Geology and Geoph

Large ripples are described from the Mesoproterozoic Hilfordy Formation in the Kimberley region,northwestern *** ripple index (RI) and ripple symmetry index (RSI) suggest the Kimberley ripples were likely generated by storm *** wave height is up to 15 23.cm and wave length is up to 70 90 *** features,incorporated with other morphological characteristics such as symmetry,steepness,ripple spacing,and compositions,agree well with the megaripples previously reported from the intertidal-nearshore settings of modern seas and the geological *** Mesoproterozoic ripples were likely generated by the storm-induced *** survey of the global record of megaripples reveals that such structures have occurred through the geological past from the Archean to present *** were particularly common in the Neoproterozoic and had the largest ripple length and ripple height among the modern and geological *** is probably because extreme storms prevailed at that *** frequent occurrence in present day beach is probably due to the prevalence of extreme storms caused by the monsoon or tsunami/earthquake influenced climatic regimes.

关键词： megaripples palaeohydrodynamics extreme storms Mesoproterozoic Hilfordy Formation Kimberley northwestern Australia