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Design and Expression of a Synthetic phyC Gene Encoding the Neutral Phytase in Pichia pastoris

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Acta Biochimica et Biophysica Sinica 2006年第11期38卷 803-811页

作者： Li-Kou ZOU~(1,3. Hong-Ning WANG~(2,1*) Xin PAN~4 Tao XIE~1 Qi WU~5 Zi-Wen XIE~1 Wan-Rong ZHOU~1 1 Laboratory of Veterinary and Biotechnology,sichuan Agricultural University,Ya'an 625014,china 2 sichuan University Bioengineering Research Center for Animal Disease Prevention and Control,{3. 610065,china 3.Faculty of Environment and resource of Dujiangyan Campus,sichuan Agricultural University,Dujiangyan 61183.,china 4 College of Earth Science,Chengd University of Technology,{3. 610059,china 5 College of Life Science,sichuan Agricultural University,Ya'an 625014,china Laboratory of Veterinary and Biotechnology Sichuan Agricultural University Ya'an 625014 China

The 1074-bp phyCs gene （optimized phyC gene） encoding neutral phytase was designed andsynthesized according to the methylotrophic yeast Pichia pastoris codon usage bias without altering theprotein *** expression vector,pP9K-phyCs,was linearized and transformed in *** of total extracellular phytase activity was 17.6 U/ml induced in Buffered Methanol-complex Medium（BMMY） and 18.5 U/ml in Wheat Bran Extract Induction （WBEI） medium at the flask scale,respectively,improving over 90 folds compared with the wild-type *** enzyme showed temperature optimumof 70℃ and pH optimum of *** enzyme activity retained 97% of the relative activity afterincubation at 80℃ for 5 *** of the heavy glycosylation the expressed phytase had a molecularsize of approximately 51 *** deglycosylation by endoglycosylase H （EndoH_f）,the enzyme had anapparent molecular size of 42 *** property and thermostability was affected by the glycosylation.

关键词： design expression synthetic phyC gene neutral phytase Pichia pastoris

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农村非农用地流转中的制度性缺陷及对策

四川师范大学学报（社会科学版） 2004年第6期31卷 29-34页

作者：唐涌四川大学经济学院四川成都610064

"三农问题"的关键是农民问题,土地是农民的命根子,它对农民具有生产资料和社会保障的双重功能,在我国经济体制改革的城市化进程中,由于观念、政策、法规、监督机制等制度性原因,使广大的农民在非农用地流转中处于弱势地位,他们的经济利... 详细信息

"三农问题"的关键是农民问题,土地是农民的命根子,它对农民具有生产资料和社会保障的双重功能,在我国经济体制改革的城市化进程中,由于观念、政策、法规、监督机制等制度性原因,使广大的农民在非农用地流转中处于弱势地位,他们的经济利益,生存空间受到威胁,必须完善农村土地产权制度,在非农用地征用、补偿等方面进行制度创新,否则稀缺的土地资源将要受到灾难性破坏。

关键词：农村非农用地土地流转制度性缺陷

Site-specific Vulnerability Assessment for Debris Flows: Two Case Studies

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Journal of Mountain Science 2006年第1期3卷 20-27页

作者： Liu Xilin institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu Sichuan 610041 China

Here the vulnerability is defined as the potential total maximum losses due to a debris flow damaging event for a specific debris flow fan. The vulnerability is classified into property vulnerability and population vulnerability. Assessment indexes include the assets of buildings, traffic facilities, lifeline works, personal properties, and land resources for property vulnerability; age, education, and wealth of the inhabitants, natural population growth rate, and population density for population vulnerability. The vulnerability is expressed as the sum of the transformed values of the losses of property and population. Two study cases with post-fact damages by historic debris flow events in sichuan of SW{3. are presented.

关键词： Vulnerability to debris flow vulnerability factors case study china

Change in Sediment Load of the Yangtze River after Wenchuan Earthquake

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Journal of Mountain Science 2010年第1期7卷 100-104页

作者： CHENG Genwei HE Xiubin CHEN Guirong TAO Heping Key Laboratory of Mountain Environment Evolvement and Regulation. institute of Mountain Hazards & Environment CAS Chengdu 610041 China Siehuan Hydrology &Water resource Survey Bureau Chengdu 610041 China

On May 12, 2008, an earthquake of 8.0 magnitude on the Richter scale and its numerous aftershocks devastatingly hit Wenchuan County and its nearby region along the Longman Mountains in sichuan Province, china. The heavy ruined area was up to 3.,000km2 and 13. of its land surface was denuded by the extremely terrible quakes. The mountain collapses, landslides and debris flows induced by the earthquake not only scared the landscape at the immense scale, but also poured L66-billion-m3.sediment combined with offscourings and rubble into the Yangtze River and its breaches. This amount of sediments is 3.times more than the normal amount discharged into the Yangtze River, and will significantly increase sediment transportation of rivers and decrease storage capacities of reservoirs downstream. The dramatic increase in sediment load will imperil the engineering safety and impact the operation of the giant Three-Gorge Hydro-power Station if no proper prevention measures are taken.

关键词： Wenchuan earthquake sediment load the Yangtze River

Algorithm of symbol generation and configuration of land polygons in present land-use map

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中国有色金属学会会刊：英文版 2011年第S3期21卷 743-747页

作者： ZUO Xiao-qing, NIE Jun-tang Faculty of land resource Engineering, Kunming University of Science and Technology, Kunming 650093. china Faculty of land resource Engineering Kunming University of Science and Technology Kunming 650093 China

The symbolization of land polygon is an important part of cartography. In the mapping of traditional present land-use maps, the symbol of land polygons was usually filled by the method of filling or plotting, but these methods can't solve the spatial conflicts of the symbol. According to the principle of cartography, the rule of how to symbolize the land polygon was summarized, and a new method that can generate and deploy the land symbols was presented. By making use of C# programming language and Arc Engine developing components, the algorithm can generate land symbols presenting triangle and adjust the coordinate of the symbol. Through mapping the present land-use map of Honghe county, this algorithm can reduce 88.84% of the spatial conflicts error rate compared with the traditional methods. It improves the accuracy and efficiency of the map symbolic.

关键词： land symbol present land use map symbol configuration spatial conflict

Systematic Design and Coordination Acts of Ecological Security in Upper Yangtze River in china

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Wuhan University Journal of Natural Sciences 2003年第3B期8卷 987-995页

作者： Fang Yi-ping, Chen Quo-jieinstitute of Mountain Hazards and Environment, Chinese Academy of Sciences, chengdu 61004., sichuan.{3. School of management, University of Electronic Science and Technology of{3., chengdu 610054, sichuan,{3. institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu 610041 Sichuan China School of management University of Electronic Science and Technology of China Chengdu 610054 Sichnan China institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu 610041 Sichuan China

In this paper, systematic design and act of eco-security is discussed as a focal point of conflict and unrest. The situation of ecosystem, the schematic framework of eco-security design, the main acts of ecosystem improvement, major difficulties and challenges have also been analyzed. The purpose of this study was to formulate the systematic framework of eco-security maintenance, to highlight systematic idea or philosophy of ecological rehabilitation and eco-security. A three-dimensional schematic model is applied to design the security of ecosystem. It was concluded that: 1) maintaining ecological security requires far better and sophisticated resource management skill and ecological improvement measures, and is also a continuing and multifac-eted task. It cannot be permanently accomplished by a single action and program; 2) at present, technical system and policy and law system dimensions of ecological security are not enough even in short; 3. development of ecological industries is beneficial to local economic development and ecosystem protection.

关键词： upper Yangtze basin ecological security systematic design eco-security maintenance

Water in peridotite xenoliths from South china

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Science china Earth Sciences 2011年第10期54卷 1511-1522页

作者： WANG Rong 1,2,3.& ZHANG BaoMin 3.1 Faculty of land resource Engineering, Kunming University of Science and Technology, Kunming 650093. china 2 State Key Laboratory for Mineral Deposits Research, Nanjing University, Nanjing 210093. china 3.Faculty of Earth Science, china University of Geosciences, Wuhan 43.074, china Faculty of land resource Engineering Kunming University of Science and Technology Kunming China State Key Laboratory for Mineral Deposits Research Nanjing University Nanjing China Faculty of Earth Science China University of Geosciences Wuhan China

The water contents of nominally anhydrous clinopyroxene （cpx）, orthopyroxene （opx） and olivine （ol） in peridotite xenoliths hosted by Cenozoic basalts from Yingfengling, Zhangchouchun, Fujitian and Lindi, South china, were measured by Micro- FTIR. All cpx and opx grains contained a certain amount of water, which was indicated by the presence of hydroxyls in the crystal structure. The water contents （H20, ppm） of cpx and opx from peridotite xenoliths of the study areas were 293.981, 183.752, 73.586 and 51-423.ppm, and 82-471, 74-571, 53.170 and 9-13. ppm, respectively. No prominent OH absorption bands were detected for any ol grains, indicating that the water contents were below the detection limit （approximately 2 ppm）. The entire rock contents recalculated according to mineral volume proportions were 49-163. 48-168, 21-111 and 8-40 ppm, respectively. Combined with previously reported data describing the water contents of peridotite xenoliths worldwide, the results presented here suggest that water distribution in the continental lithospheric mantle is spatially heterogeneous at a global scale. The lithospheric mantle of South china is much richer in water than that of the North china Craton, and is close to that typical of off-craton localities, such as the Basin and Range Province, and Massif Central.

关键词： FTIR water peridotite xenoliths South china

Spatial Interpolation and Sample Size Optimization for Soil Copper(Cu) Investigation in Cropland Soil at County Scale Using Cokriging

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Agricultural Sciences in china 2009年第11期8卷 1369-1377页

作者： PANG Su,LI Ting-xuan,WANG Yong-dong,YU Hai-ying and LI Xi College of resource and Environmental Science,sichuan Agricultural University,Ya’an 625014,P.R.china College of resource and Environmental Science Sichuan Agricultural University Ya'an 625014 P.R. China

Knowledge on spatial distribution and sampling size optimization of soil copper （Cu） could lay solid foundations for environmetal quality survey of agricultural soils at county scale. In this investigation, cokriging method was used to conduct the interpolation of Cu concentraiton in cropland soil in Shuangliu County, sichuan Province, china. Based on the original 623.physicochmically measured soil samples, 560, 498, and 43. sub-samples were randomly selected as target variable and soil organic matter （SOM） of the whole original samples as auxiliary variable. Interpolation results using Cokriging under different sampling numbers were evaluated for their applicability in estimating the spatial distribution of soil Cu at county sacle. The results showed that the root mean square error （RMSE） produced by Cokriging decreased from 0.9 to 7.77%, correlation coefficient between the predicted values and the measured increased from 1.76 to 9.76% in comparison with the ordinary Kriging under the corresponding sample sizes. The prediction accuracy using Cokriging was still higher than original 623.data using ordinary Kriging even as sample size reduced 10%, and their interpolation maps were highly in agreement. Therefore, Cokriging was proven to be a more accurate and economic method which could provide more information and benefit for the studies on spatial distribution of soil pollutants at county scale.

关键词： cropland soil county scale copper Cokriging sampling size

A family net of giant pandas in the Tangjiahe Natural Reserve:Assessment of current individual migration

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Science Bulletin 2005年第17期 65-72页

作者： WAN Qiuhong1, FANG Shengguo1, LI Jianguo2, ZHANG Liming 3. OU Weifu4, XIAN Fanghai4 & CHEN Wanli4 1. College of Life Sciences, State Conservation Center for Gene Re-sources of Endangered Wildlife, and Key Laboratory of Conservation Genetics and Reproductive Biology for Endangered Wild Animals of Ministry of Education, Zhejiang University, Hangzhou 3.0029, china 2. Forestry Department of sichuan Province, chengdu 610081, china 3. sichuan Bureau for Wildlife resource Investigation, Conservation and management, chengdu 610082, china 4. Tangjiahe Natural Reserve, Qingchuan 628109, china

In the present study, formalin-fixed feces, oli-gonucleotide fingerprinting and SRY-gene based sexing were used to construct a family net for giant pandas in the Tang-jiahe Natural Reserve and to assess contemporary gene flow (migration) in this population. A total of 124 fecal samples were attributed to 3. individuals (22 females and 15 males) that were then analyzed for family relationships. Based on DNA fingerprints, the deduced family net revealed the fol-lowing facts: (i) First-order relatives possessed similarities from 50% to 90%, and similarities between unrelated indi-viduals or distant relatives were as high as 77%, indicating that the Tangjiahe pandas are characterized by high genetic similarity; (ii) 15 matings were identified and 5 ones oc-curred between close relatives, implying that there is poten-tial for inbreeding to impact the pandas; (iii) four mating pairs and 5 offspring presented long distance migrations, demonstrating the intra-reserve habitat is continuous; (iv) four pairs of full sibs (also female-male dyads) dispersed short distance and all of them gave birth to highly inbred offspring, reflecting long distance migration is vital for in-breeding avoidance; (v) 17 adult individuals dispersed short or moderate distance and formed three clusters on the land-scape, indicating that it is necessary to find out whether there is a negative factor impacting the pandas.

关键词： multilocus DNA fingerprinting giant panda family rela-tionship close inbreeding dispersal pattern.