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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 {4., Chinese Academy of Sciences, Beijing 100085, china 5. College of Resources and Environment, Southwest Agricultural university, Chongqing 4.0716, 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.

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Types of voltage-dependent calcium channels involved in high potassium depolarization-induced amylase secretion in the exocrine pancreatic tumour cell line AR4.2J

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Cell Research 1998年第1期8卷 23-31页

作者： CUI ZONG JIE (Beijing Agricultural university Faculty of biological Sciences Beijing 100094. china) Beijing Agricultural university Faculty of biological Sciences Beijing 100094 China

In the perifused fura-2 loaded exocrine pancreatic acinar cell line AR4.2J pulses of high potassium induced repetitive increases in intracellular calcium. Attached cells when stimulated with high potassium secreted large amount of amylase. High potassium-induced secretion was dependent both on the concentration of potassium and duration of stimulation. High potassium induced increases in intracellular calcium were inhibited by voltage-dependent calcium channel antagonists with an order of potency as follows: nifedipine > ω-agatoxin IVA > ω-conotoxin GVIA. In contrast, the L-type calcium channel antagonist nifedipine almost completely inhibited potassium-induced amylase secretion, whereas the N-type channel antagonist ω-conotoxin GVIA was without effect. The P-type channel antagonist ω-agatoxin IVA had a small inhibitory effect, but this inhibition was not significant at the level of amylase secretion. In conclusion, the AR4.2J cell line possesses different voltage-dependent calcium channels (L, P,N) with the L-type predominantly involved in depolarization induced amylase secretion.

关键词： AR4.2J pancreatic acinar cells amylase secretion calcium channels

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Enhancement of monacolin K production via intergeneric protoplast fusion between Aspergillus terreus and Monascus anka

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Progress in Natural Science:Materials International 2007年第6期17卷 703-707页

作者： Chen Zhi, Lin Wen, Yu Ping and Song Yuan(Department of Microbiology, College of biological Sciences, china Agricultural university, Beijing 100094. china) Department of Microbiology College of Biological Sciences China Agricultural University Beijing 100094 China

Intergenric protoplast fusion between Aspergillus terreus CA99 and Monascus anka M-3, the high and low producers of monacolin K respectively,was performed for enhancement of monacolin K production. The 24.hour-old mycelia of A. terreus CA99 and M. anka M-3 were treated with 0.5% lywallzyme, 0.3% snailase and 0.3% cellulase at 34. for 5 h and at 30℃ for 3.5 h, and their protoplasts formation reached 1.76×107/mL and 1.68×107/mL respectively. Parental protoplasts were irradiated with a 30 W UV light away from 30 cm for 3 min and then mixed. The mixture was incubated with 30% PEG 6000 for 15 min. The reviving fusants were isolated on the regeneration plates. Of the 363 fusants isolated, over 100 showed enhanced monacolin K production compared with the parental strain M. anka M-3. Ten of them produced monacolin K about 1.6-fold of that *** M-3 does and the monacolin K titer of two fusants (F4. and F104. increased by about 1-fold. The monacolin K yields of F4. and F104.were 4.0 μg/mL and 4.7 μg/mL respectively. In optimized fermentation medium, the monacolin K titer of F4. reached 1216 μg/mL.

关键词： monacolin K Monascus anka Aspergillus terreus protoplast fusion fermentation.

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Stem cells and neurodegenerative diseases

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Science china(Life Sciences) 2008年第4期51卷 287-294页

作者： HOU LingLing & HONG Tao Institute of biological Science and Technology, Beijing Jiaotong university, Beijing 10004., china 1. Institute of biological Science and Technology Beijing Jiaotong University Beijing 100044 China

Neurodegenerative diseases are characterized by the neurodegenerative changes or apoptosis of neurons involved in networks, which are important to specific physiological functions. With the de-velopment of old-aging society, the incidence of neurodegenerative diseases is on the increase. How-ever, it is difficult to diagnose for most of neurodegenerative diseases. At present, there are too few effective therapies. Advances in stem cell biology have raised the hope and possibility for the therapy of neurodegenerative diseases. Recently, stem cells have been widely attempted to treat neurodegen-erative diseases of animal model. Here we review the progress and prospects of various stem cells, including embryonic stem cells, mesenchymal stem cell and neural stem cells and so on, for the treatments of neurodegenerative diseases, such as Parkinson’s disease, Alzheimer’s disease, Hunt-ington’s disease and Amyotrophic lateral sclerosis/Lou Gehrig’s disease.

关键词： stem cells neurodegenerative diseases therapy

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Experimental study on pressurized activated sludge process for high concentration pesticide wastewater

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Journal of Environmental Sciences 2010年第9期22卷 1342-1347页

作者： Zanfang Jin, Zhiyan Pan, Shangqin Yu, Chunmian Lin College of biological and Environmental Engineering, Zhejiang university of Technology, Hangzhou 310032, china. [a] College of biological Environmental Engineering Zhejiang University of Technology Hangzhou 310032 China

Pressurized biochemical process derived from traditional activated sludge processes is an innovative technology for wastewater treatment. The main advantage of the pressurized process is that the oxygen transfer barrier can be overcome by increasing the dissolved oxygen level. In this study, high concentration pesticide wastewater was treated by pressurized activated sludge process. It was found that the removal of chemical oxygen demand （COD） increased steadily with the increase of operating pressure, aeration time, and sludge concentration. When the operation pressure was 0.30 MPa and the aeration time was 6 hr, 85.0%-92.5% COD, corresponding to an effluent COD of 230-370 mg/L, was removed from an influent COD of 2500-5000 mg/L. The obtained outlet COD concentration was lower than 350-4.0 mg/L for the identical process operated under the atmospheric pressure. In addition, pressurized biochemical process could produce a higher COD volumetric loading rate at 5.8-7.6 kg COD/（m^***）, compared with 2.0-2.8 kg COD/（***） using the same equipment at the atmospheric pressure. The COD concentration followed a modified Monod model with Vmax 2.31 day-1 and Ks 4.7 mg/L.

关键词： pressurized biochemical process pesticide wastewater activated sludge kinetics

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Updating verbal and visuospatial working memory: Are the processes parallel?

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Chinese Science Bulletin 2008年第14期53卷 2175-2185页

作者： YUE ZhenZhu1,2, ZHANG Ming3,4.& ZHOU XiaoLin1 1 Department of Psychology, Peking university, Beijing 100871, china 2 biological Psychology and Neuropsychology, university of Hamburg, Von-Melle-Park 11, 2014. Hamburg, Germany 3 Department of Psychology, Northeast Normal university, Changchun 130024. china 4.Key Laboratory for Applied Statistics of MOE, Northeast Normal university, Changchun 130024. china NE Normal Univ Dept Psychol Changchun 130024 Peoples R China.

The current study compared the processes of updating verbal and visuospatial working memory (WM) and examined the roles of central executive and slave systems in working memory updating tasks, by changing the number of items updated simultaneously to manipulate the load on central executive. Ex- periment 1 used the verbal WM updating task, and the results validated the efficiency of the paradigm to manipulate the load on central executive. Experiment 2 employed the verbal WM updating task, with the articulatory suppression task to interfere with the phonological loop. The results supported the study by Morris and Jones, revealing that the central executive system played an important role in the updating component of verbal WM, while the phonological loop was responsible for the serial recall component. Experiment 3 employed the visuospatial WM updating task, with the spatial tapping task to interfere with the visuospatial sketchpad. The results suggested that the visuospatial sketchpad and the central execu- tive together dealt with the updating component, while the visuospatial sketchpad was responsible for the serial recall component by itself. These results are consistent with the findings that visuospatial sketch- pad has close links with central executive, while the phonological loop is separated from the central ex- ecutive. It suggests that updating visuospatial and verbal WM are not two parallel processes.

关键词：记忆储存工作记忆中枢神经视觉性

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Identification and Characterization of glnA Promoter and its Corresponding Trans-regulatory Protein GlnR in the Rifamycin SV Producing Actinomycete,Amycolatopsis mediterranei U32

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Acta Biochimica et Biophysica Sinica 2006年第12期38卷 831-843页

作者： Hao YU~(1&) Wen-Tao PENG~1 Yang LIU~1 Ting WU~2 Yu-Feng YAO~1 Ming-Xue CUI~1 Wei-Hong JIANG~1 Guo-Ping ZHAO~(1,3,4.) 1 Laboratory of Molecular Microbiology,Institute of Plant Physiology and Ecology,Shanghai Institutes for biological Sciences,Chinese Academy of Sciences,Shanghai 200032,china 2 Department of Medicinal Chemistry,School of Pharmacy,Fudan university,Shanghai 200032,china 3 State Key Laboratory of Genetic Engineering & Department of Microbiology,School of Life Science,Fudan university,Shanghai 2004.3,china 4.Laboratory of Disease and Health Genomics,Chinese National Human Genome center at Shanghai,Shanghai 201203,china Laboratory of Molecular Microbiology Institute of Plant Physiology and Ecology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Shanghai 200032 China Department of Medicinal Chemistry School of Pharmacy Fudan University Shanghai 200032 China State Key Laboratory of Genetic Engineering & Department of Microbiology School of Life Science Fudan University Shanghai 200433 China Laboratory of Disease and Health Genomics Chinese National Human Genome Center at Shanghai Shanghai 201203 China

The genetic requirements for the transcription of glnA,encoding the major glutaminesynthetase in a rifamycin SV-producing Amycolatopsis mediterranei strain,U32,were *** experiments showed that the promoter of U32 glnA （pglnA） was likely to have two transcriptioninitiation sites:P1and P2,located 157 and 4. nucleotides （nt） upstream of the translational start codon,*** mobility shift and DNase I footprinting analyses revealed a 30 bp cis-element locatedat 4. to 75 nt downstream of P1,or 38 to 68 nt upstream of *** sequence of the cis-element displayedhigh similarity to the corresponding regions of pglnA from Streptomyces coelicolor and *** as a reporter gene,the expression levels of U32 pglnA and its deletion derivatives under differentnitrogen-source conditions were analyzed by detecting the catechol dioxygenase activities in ***54.*** J508 and *** FS10 （glnR mutant）.These in vivo studies showed that theactivation of U32 pglnA in *** required GlnR,and its binding to the U32 pglnA was furtherconfirmed by the gel mobility shift *** and heterologous expression of the U32 glnR allowed usto detect the in vitro interaction between the U32 GlnR and the corresponding pglnA *** shown by in vivo glnR inactivation and complementation indicated that GlnR is essential for theactive transcription of glnA in U32.

关键词： glnA promoter cis-element glnR Amycolatopsis mediterranei

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Chemical Composition and biological Activities of Essential Oil from the Rhizomes of Iris bulleyana in yunnan Province,Southwest of china

Chemical Composition and Biological Activities of Essential ...

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The 1st International Conference on Plant Secondary Metabolism

作者： Guobin Deng Xiaolan Chen Shanna Chen~* Department of biotechnology yunnan university kunming 650091 P R.{4.

＜正＞The genus Iris belongs to the family Iridacea comprising over 220 species,58 of which are found in *** species have an immense medicinal importance that are used in the treatment of cancer,inflammation,bacterial and viral *** bulleyana distributes mainly in yunnan Province,southwest of china,has a long history of use in folk *** healers in Southwest of china use it to eliminate stasis and resolve swelling. Hydrodistillation was used to extract the essential oil from the rhizomes of Iris *** essential oil yield

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Sm-Nd isotopic ages of Tiqiushan eclogites in Xinyi region and its geological significance

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Chinese Science Bulletin 1999年第S2期44卷 144-146页

作者： WANG Yinxi~(1,2), YANG Jiedong~(1,2), TAO Xiancong~(1,2), GE Ningjie~4. CHEN Peirong~3, FAN Chunfang~3 and LI Jianhua~5 1. center of modern Analysis, Nanjing university, Nanjing 210093, china 2. State Key Laboratory for Research of Mineral Deposits, Nanjing university, Nanjing 210093, china 3. Department of Earth Science, Nanjing university, Nanjing 210093, china 4. Department of Earth and Space Sciences, university of Science and Technology of Chian, Hefei 230026, china 5. No.5 Geological Party of Jiangsu Province, Xuzhou 221005, china center of modern Analysis Nanjing University Nanjing 210093 China State Key Laboratory for Research of Mineral Deposits Nanjing University Nanjing 210093 China Department of Earth and Space Sciences University of Science and Technology of Chian Hefei 230026 China Department of Earth Science Nanjing University Nanjing 210093 China No. 5 Geological Party of Jiangsu Province Xuzhou 221005 China

GEOLOGICAL scientists have paid much attention to the suture zones formed by collision between the Sino-Korean and Yangtze blocks because of the discovery of the ultrahigh pressue metamorphic (UHPM) rocksfrom northern Jiangsu Province (Su), southern Shandong Province (Lu) and the Dabie *** the age of 200-24. Ma is probably the best estimation for UHPM metamorphism in the DabieMountains, the primary intrusive and metamorphic ages of the complex from northern Jiangsu Provincehave not been determined before. Using the Sm-Nd isotopic dating method, our study is aimed at datingthe UHPM metanorphic event of northern Jiangsu Province and researching a probable relation between theUHPM rocks from the Dabie Mountains and the UHPM rocks from northern Jiangsu Province.

关键词： northern Jiangsu eclogite rocks Sm-Nd isotopic ages.

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Optimizing aerobic biodegradation of dichloromethane using response surface methodology

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Journal of Environmental Sciences 2009年第9期21卷 1276-1283页

作者： WU Shijin,YU Xiang,HU Zhihang,ZHANG Lili,CHEN Jianmeng College of biological and Environmental Engineering,Zhejiang university of Technology,Hangzhou 310032,china [a]College of biological and Environmental Engineering Zhejiang University of Technology Hangzhou 310032 China. E-mail: wujan28@***

Response surface methodology （RSM） was employed to evaluate the optimum aerobic biodegradation of dichloromethane （DCM） in pure culture. The parameters investigated include the initial DCM concentration, glucose as an inducer and hydrogen peroxide as terminal electron acceptor （TEA）. Maximum aerobic biodegradation efficiency was predicted to occur when the initial DCM concentration was 380 mg/L, glucose 13.72 mg/L, and H202 115 mg/L. Under these conditions the aerobic biodegradation rate reached up to 93.18%, which was significantly higher than that obtained under original conditions. Without addition of glucose degradation efficiencies were ≤ 80% at DCM concentrations ≤ 326 mg/L. When concentrations of DCM were more than 4.0 rag/L, the addition of hydrogen peroxide did not help to significantly increase DCM degradation efficiency. When DCM concentrations increased from 24. to 4.0 rag/L, the overall DCM degradation efficiency decreased from 91% to 60% in the presence of HaO2 for 120 mg/L.

关键词： biodegradation dichloromethane response surface methodology

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