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Enzymatic cyclization of linear peptide to plant cyclopeptide heterophyllin B

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Science China Chemistry 2006年第1期49卷 63-66页

作者： JIA Aiqun1, LI Xiang2, TAN Ninghua1, LIU Xiaozhu3, SHEN Yuemao1 & ZHOU Jun1 1. State Key Laboratory of Phytochemistry and Plant Resources in West China, Kunming Institute of Botany, Graduate Univer-sity of Chinese Academy of Sciences, Chinese Academy of Sciences, Kunming 650204, China 2. Chinese Peptide Co., Ltd, Hangzhou 310018, China 3. Southwest forestry college, Kunming 650204, China 1. State Key Laboratory of Phytochemistry and Plant Resources in West China Kunming Institute of Botany Graduate University of Chinese Academy of Sciences Chinese Academy of Sciences Kunming 650204 China 2. Chinese Peptide Co. Ltd Hangzhou 310018 China 3. Southwest forestry college 650204 Kunming China

The crude enzyme (PH-1) isolated from Pseudostellaria heterophylla by ourgroup has catalyzed enzymatic cyclization of linear peptideNH_2-Gly^1-Gly^2-Leu-Pro-Pro-Pro-lle-Phe-COOH (4) into cyclopeptide heterophyllin B (HB) from plantfor the first time. To ensure this reaction, some analytical methods including TLC, HPLC, MS, NMR,and ^(13)C labeling were used to prove that the reaction of substrate 4 sharing residue ofNH-Phe-Gly-CO was successful.

关键词： Pseudostellaria heterophylla, cyclopeptides, HB, enzymatic cyclization, isotope labeled.

Prokaryotic Expression of Mouse Sox2 Gene and Preparation of Its Polyclonal Antibody

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农业生物技术学报 2010年第6期18卷 1163-1167页

作者： Lei Lei Cui Xinxin Zhang Shujin Wang Huayan college of Veterinary Medicine, Shaanxi Key Laboratory of Molecular Biology for Agriculture, Shaanxi Center for Stem Cell Engineering and Technology, Northwest Agriculture and forestry University, Yangling 712100, China college of Veterinary Medicine Shaanxi Center for Stem Cell Engineering and Technology Northwest Agriculture and Forestry University Shaanxi Key Laboratory of Molecular Biology for Agriculture Yangling 712100 college of Veterinary Medicine Shaanxi Center for Stem Cell Engineering and Technology Northwest Agriculture and Forestry University Shaanxi Key Laboratory of Molecular Biology for Agriculture Yangling 712100

Sox2, one of genes which express in embryonic stem (ES) cells, plays an important role in self renewal of ES cells, and is used to make induced pluripotent stem (iPS) cells. In this study, we subcloned mouse (Mus muscules) full-length Sox2 cDNA and inserted Sox2 into pET-41a expression vector. Then the recombinant vector was transformed into Escherichia coli BL21 (DE3) cells to express Sox2 fusion protein. The expressed products were identified by Western blot using anti-GST antibody. The result indicated that the size of Sox2 fusion protein was in 61 kD. And the protein was recovered from the SDS-PAGE. And we used the sox2 fusion protein to prepare polyclonal antibody. The Dot blotting result showed that the anti-Sox2 antiserum had 1∶12,800 titers. The antibody will be useful for studying the function of Sox2 and its role in ES cell self-renewal.

关键词： Sox2 Expression Antibody Escherichia coli

THE MASS SPECTRA OF HKTEROCYCLIC CONJUGATED COMPOUND AND ITS QUANTUM CHEMICAL CALCULATIONS

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Chemical Research in Chinese Universities 1986年第1期4卷 19-24页

作者： Fang yaoren(Laboratory of Organic Chemistry,Beijing college of forestry)Lai Zhugen,Liang Desheng and Lu Fengcai(Institute of Chemistry,Academia Sinica,Beijing)

A mechanism of cleft-rate-determining-step of furfurol,furylacrylic acid,dimethylfuran,thiophene-2-aldehyde,and pyrrole-2-aldehyde ***,and various quantum parameters of molecular ions of these compounds and their fragments are calculated by using CNDO/2 *** peak-height of mass spectra is quantitatively *** method could be extended to heterocyclic conjugated compounds.

关键词：中国科学 CNDO THE MASS SPECTRA OF HKTEROCYCLIC CONJUGATED COMPOUND AND ITS QUANTUM CHEMICAL CALCULATIONS 元生 CHO 唐敖庆 ITS

Structure changes and succession dynamic of the natural secondary forest after severe fire interference

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Journal of forestry Research 2009年第2期20卷 123-130页

作者： LIU Bin-fan1,2, LIU Guang-ju2 , WANG Zhi-cheng3 1college of forestry, Northeast forestry University, Harbin 150040, P.R.China 2Heilongjiang Forest Engineering and Environment Research Institute, Harbin 150081, P.R.China 3Heilongjiang Forest Fire Prevention Office, Harbin 150090, P.R.China college of forestry Northeast Forestry University Harbin 150040 P. R. China Heilongjiang Forest Engineering and Environment Research Institute Harbin 150081 P.R. China Heilongjiang Forest Fire Prevention Office Harbin 150090 P.R. China

The structure and dynamic succession law of natural secondary forest after severe fire interference in recent 20 years were studied by adopting the method of deducing time series from the spatial sequence of vegetation in Heihe region, Heilongjiang, *** typical and widely distributed forest types in the study area, namely forest type A and forest type B, were selected as study *** type A is pure broadleaf forest or broadleaf mixed forest mainly composing of superior Betula platyphylla and Populus davidiana in the area with gradient 25°.Species richness, vegetation coverage, important value, and similarity index of community in different layers(Herb, shrub, small tree, and arbor layers) were investigated and analyzed for the two typical *** results show that after fire interference, the species richness and coverage in each layer in forest type A were higher than that in forest type *** for forest type A and B, with elapse of post-fire years, the species richness and coverage of herbs and shrubs showed a decline tendency, while those of arbor layer present a rising *** comparison of the important values of species in each layer and analysis of community structure changes, the dynamic process of post-fire vegetation succession for forest type A and B was separately ***-fire 80 years' succession tendency of forest type A is *** and Larix gmelinii mixed *** shrub layer is mainly composed of Corylus heterophylla and Vaccinium uliginosum, and herb layer is dominated by Carex tristachya, Athyrium multidentatum, and Pyrola incarnate;whereas, the post-fire 80 years' succession of forest type B is *** and *** mixed *** shrub layer is mainly composed of lespedeza bicolar and corylus heterophylla and herb layer is dominated by Carex tristachya,

关键词： natural secondary forest vegetation succession fire interference burned areas species richness important value similarity index succession law.

Semi-fragile Image Watermarking Algorithm Based on Visual Features

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International Journal of Systems and Control

International Journal of Systems and Control 2007年第3期 176-187页

作者： Che Shengbing, Huang Da,Huang Qiangbo college of Computer Science, Central South University of forestry & Technology Hunan Changsha 410004, China

In order to identify the copyright of digital media and improve the invisibility and robustness of semi-fragile watermarking, this paper presents characteristic parameters and it’s representation in DWT domain based on visual features model of man and then proposes the Quantized Central Limit Theorem which is applied to adjusting the coefficient in general transform domain . These all can make semi-fragile watermarking embedded during the process of dynamic quantization achieve the greatest robustness. It leads up to the fact that the good invisibility of carrier image, the better robustness to the image processing (such as JPEG compression, noise adding, smoothing filtering) and the larger amount of embedded information. What’s more, it can locate the attacked position exactly.

关键词： zero-watermarking Filter bank haar wavelet two dimensional discrete wavelet transform

Decision Support in Selection Cutting Planning of Uneven－aged Stand Management

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Forest Ecosystems 1994年第2期 22-35页

作者： Song Tieying , Zhou Wenchao , Feng Xiulan college of Forest Resources and Environment,Beijing forestry University Beijing 100083,P,R,China

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ＤｅｃｉｓｉｏｎＳｕｐｐｏｒｔｉｎＳｅｌｅｃｔｉｏｎＣｕｔｔｉｎｇＰｌａｎｎｉｎｇｏｆＵｎｅｖｅｎ－ａｇｅｄＳｔａｎｄＭａｎａｇｅｍｅｎｔＳｏｎｇＴｉｅｙｉｎｇ，ＺｈｏｕＷｅｎｃｈａｏ，ＦｅｎｇＸｉｕｌａｎＣｏｌｌｅｇｅｏｆＦｏｒｅｓｔＲｅｓｏｕｒｃ...

关键词： uneven-aged stand management selection cutting forest management planning decision support system

CHARACTERISTICS OF LIGNIN REACTIONS IN SODA COOKING OF WHEAT STRAW PART 1 REACTION OF UNCONDENSED LIGNIN

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天津科技大学学报 2004年第A2期19卷 115-118页

作者： HuaminZhai YuanzongLai collegeofChemicalEngineering NanjingForestryUniversityNanjingChina210037 PaperScienceandEngmeeringFaculty stateUniversityofNewYorkCollegeofEnvironmentalScienceandForestrySyracuseNY13210USA

Characteristics of uncondensed lignin reactions in soda cooking of wheat straw were studied. Mild and intense cooking conditions were used to get the pulp sample in which lignin was dissolved physically and the pulp sample in which lignin was dissolved chemically respectively. The pulp samples were analyzed by phenolic group determination, alkaline nitrobenzene oxidation and ozonation method. The results indicated that around 90% of lignin in wheat straw is alkali-soluble at the mild conditions, is basically dissolved physically without chemical change. The phenolic group content was not changed greatly, the nitrobenzene oxidation yield only changed slightly during the mild cooking. The phenolic group content was increased obviously and uncondensed lignin content was decreased very much when the intense cooking conditions were applied and the delignification was over 90%. The lignin structure was changed greatly during this period.

关键词：小麦秸杆木质素反应苏打碱性烹饪不凝结木质素纸浆臭氧分析

The impact of vegetation restoration on erosion-induced sediment yield in the middle Yellow River and management prospect

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Science China Earth Sciences 2005年第6期48卷 724-741页

作者： CHEN Hao1, ZHOU Jinxing2, CAI Qiangguo1, YUE Zhongqi3, LU Zhongchen4, LIANG Guanglin1& HUANG Jianguo5 1. Key Laboratory of Water Cycle and Related Land Surface Processes, Institute of Geographic Sciences and Natural Resources Re-search, Chinese Academy of Sciences, Beijing 100101, China 2. Institute of forestry, Chinese Academy of forestry Sciences, Beijing 100091, China 3. Department of Civil Engineering, University of Hong Kong, Hong Kong, China 4. Eco-environmental Research Center, Chinese Academy of Sciences, Beijing 100085, China 5. college of Resources and Environment, Southwest Agricultural University, Chongqing 400716, China Correspondence should be addressed to Chen Hao 1. Key Laboratory of Water Cycle and Related Land Surface Processes Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences 100101 Beijing China 2. Institute of forestry Chinese Academy of Forestry Sciences 100091 Beijing China 3. Department of Civil Engineering University of Hong Kong Hong Kong China 4. Eco-environmental Research Center Chinese Academy of Sciences 100085 Beijing China 5. college of Resources and Environment Southwest Agricultural University 400716 Chongqing China

According to the characteristics of water and erosion environments of different natural zones on the Loess Plateau, this paper studies changes of vegetation types, distribution boundaries of forest and grass as well as restoration capacity of vegetation in different natural zones in the middle Yellow River. The annual precipitation of 530 mm is the critical annual pre-cipitation for forest and grass distribution in the middle Yellow River. Among the zonal and azonal environmental factors affecting watershed sediment yield, the intermediate diameter D50 (mm) of suspended load and forest coverage (V, %) play the leading role. Of them the effect weight of forest coverage (V, %) on catchments sediment yield is only 3.4% less than the role of the intermediate diameter (D50, mm), they are almost the same. To effectively control soil erosion in semiarid, especially in hilly-gullied areas and make sediment transport modulus reduce to less than 6000 t/km2, it is rather difficult by merely relying on natural restoration of forest. In the process of cultivated land conversion into forest land and grassland, measures suiting local conditions should be adopted in tree species selection and artificial afforestation (grass planting) based on management with biological measures for slopeland and engineering measures for hilly-gullied areas, so that watershed forest coverage in key counties can reach at least over 30%.Compared with the standard period of precipitation prior to the 1960s, with the decrease of an-nual precipitation at various periods, plant productivities decline to different degrees under natural conditions. The main reason accountable for the low survival rate of new seedlings and grass over years is due to precipitation decrease. In light with regression models of annual pre-cipitation and natural vegetation productivities, it is possible to obtain estimated values of wa-tershed natural vegetation productivity and eco-water consumption needed for the restoration to

关键词： vegetation restoration, eco-water requirement, watershed sediment yield, the middle Yellow River.

Fractional Order Compensator of Slide Mode for Delay Control System with Uncertain Parameters

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Fractional Order Compensator of Slide Mode for Delay Control...