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An improved method for phasing crystal structures with low non-crystallographic symmetry using cryo-electron microscopy data

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Protein & Cell 2015年第12期6卷 919-923页

作者： Jia Wang (1) (2) (3) Weiguang Wang (1) (2) Wen Song (2) (3) (4) Zhifu Han (2) (3) (4) Heqiao Zhang (2) (3) (4) Jijie Chai (2) (3) (4) Hongwei Wang (2) (3) (4) Jiawei Wang (1) (2) 1.State Key Laboratory of membrane Biology School of Life Sciences Tsinghua University Beijing 100084 China 2.Center for Structural Biology School of Life Sciences Tsinghua University Beijing 100084 China 3.Tsinghua-Peking Center for Life Sciences School of Life Sciences Tsinghua University Beijing 100084 China 4.Ministry of Education Key Laboratory of Protein Science School of Life Sciences Tsinghua University Beijing 100084 China

Cryo-electron microscopy （cryo-Em） and macromolecular crystallography （mX） both allow the creation of three-dimensional images of biological macromolecules. Em data usually provide access to three-dimensional reconstructions of large biological complexes at low resolution, whereas mX usually delivers atomic or quasi-atomic resolution structures （1-3 A）.

关键词： Phase Error molecular Replacement Histogram match TLR13 molecule Solvent Flatten

RESIdENTS' ATTITUdES TO TOURISm dEVELOPmENT IN ANCIENT VILLAGE RESORTS——Case Study of World Cultural Heritage of Xidi and Hong Villages

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Chinese Geographical Science 2004年第2期 76-84页

作者： WANG Li~1, LU Lin~1, TONG Shi-rong~2, LU Song~1, YANG Zhao~1, WANG Yong~1, LIANG dong-dong (1.College of Tourism, Anhui Normal University, Wuhu 241000, P. R. China 2. Tourism Bureau of ma'anshan City, ma'anshan 243000, P. R. China) College of Tourism， Anhui Normal University， Wuhu 241000， P. R. China Tourism Bureau of ma'anshan City， ma'anshan 243000， P. R. China

Tourism development surely has social, economic and environmental impacts on tourist destinations. The study on resorts residents' attitudes can help understand the nature of tourism development and the extent to which it may influence on tourist destinations. By now, researches on residents' perception and attitudes are plenteous in the international circle and achievements are great, yet few are found in developing countries. As a most representative cultural tourist destination, World Cultural Heritage-Xidi and Hong villages in Yi County of Anhui Province, are drawing the attention of both tourists and academic circles. This article, taking Xidi and Hong villages as examples, seeks to analyze ancient village residents' attitudes towards tourism impacts and then tries further to explore the connection between tourism development and residents' attitudes. Both qualitative and quantitative surveys are applied in the exploratory investigation into local residents' attitudes of tourism impacts. Based on a

关键词： ancient village resort Xidi and Hong villages residents’ attitudes

Inhibitory Effects of microRNA-34a on Cell migration and Invasion of Invasive Urothelial Bladder Carcinoma by Targeting Notch1

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Journal of Huazhong University of Science and Technology(medical Sciences) 2012年第3期32卷 375-382页

作者：张超姚志勇朱鸣阳马鑫史涛坪李宏召王保军欧阳金芝张旭 department of Urology Chinese PLA General Hospital Nankai University department of Urology Air Force General Hospital of PLA department of Endocrinology Chinese PLA General Hospital

microRNAs （miRNAs or miRs） are a class of short, non-coding RNAs that participate in various oncological processes. This study aims to explore the roles of microRNA-34a （miR-34a） in invasive urothelial bladder carcinoma. miR-34a was transfected into bladder cancer cell lines 253J and J82. The miR-34a expression levels in tissues and cells were detected by using qRT-PCR. The Notch1 expression was detected by qRT-PCR and Western blotting. Cell migratory and invasive abilities were measured by Transwell chamber assay. Bioinformatics and luciferase assay were performed to predict and analyze the binding sites between miRNA-34a and Notch1. It was found that there was aberrant expression of miR-34a in bladder cancer tissues. moreover, we revealed that ectopic expression of miR-34a suppressed cell migration and invasion, while forced expression of Notch1 increased cell migratory and invasive abilities. Finally, we observed that miR-34a transfection significantly down-regulated luciferase activity and reduced the mRNA and protein levels of Notch1. Our study concluded that microRNA-34a antagonizes Notch1 and inhibits cell migration and invasion of bladder cancer cells, which indicates the tumor-suppressive function of microRNA-34a in bladder cancer.

关键词： microRNA-34a urothelial carcinoma migration invasion Notch1

Novel encryption model for multimedia data

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Journal of Systems Engineering and Electronics 2009年第5期20卷 1081-1085页

作者： Ye dengpan~(1,2) & Lian Shiguo~3 1.The Key Laboratory of Aerospace Information Security and Trust Computing,ministry of Education,Wuhan 430072,P.R.China 2.School of Computer Science,Wuhan Univ.,Wuhan 430072,P.R.China 3.France Telecom R&d Beijing,Beijing 100080,P.R.China The Key Laboratory of Aerospace Information Security and Trust Computing Ministry of Education Wuhan 430072 P. R. China School of Computer Science Wuhan Univ. Wuhan 430072 P. R. China France Telecom R&d Beijing Beijing 100080 P. R. China

A novel encryption model is proposed. It combines encryption process with compression process, and realizes compression and encryption at the same time. The model＇s feasibility and security are analyzed in detail. An... 详细信息

关键词： multimedia encryption model compression feasibility security.

Hydrocarbon migration and accumulation along the fault intersection zone-a case study on the reef-flat systems of the No.1 slope break zone in the Tazhong area, Tarim Basin

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Petroleum Science 2010年第2期7卷 211-225页

作者： Xiang Caifu Pang Xiongqi Yang Wenjing Wang Jianzhong LiQiming Liu Luofu Li Yanqun State Key Laboratory of Petroleum Resources and Prospecting China University of Petroleum Beijing 102249 China Basin and Reservoir Research Center School of Natural Resources and Information Technology China University ofPetroleum Beijing 102249 China PetroChina Tarim Oilfield Company Korla Xinjiang 841000 China

Understanding hydrocarbon migration and accumulation mechanisms is one of the key scientif ic problems that should be solved for effective hydrocarbon exploration in the superimposed basins developed in northwest China. The northwest striking No.1 slope break zone, which is a representative of superimposed basins in the Tarim Basin, can be divided into five parts due to the intersection of the northeast strike-slip faults. Controlled by the tectonic framework, the types and properties of reservoirs and the hydrocarbon compositions can also be divided into five parts from east to west. Anomalies of all the parameters were found on the fault intersection zone and weakened up-dip along the structural ridge away from it. Thus, it can be inferred that the intersection zone is the hydrocarbon charging position. This new conclusion differs greatly from the traditional viewpoint, which believes that the hydrocarbon migrates and accumulates along the whole plane of the No.1 slope break zone. The viewpoint is further supported by the evidence from the theory of main pathway systems, obvious improvement of the reservoir quality （2-3 orders of magnitude at the intersection zone） and the formation mechanisms of the fault intersection zone. differential hydrocarbon migration and entrapment exists in and around the strike- slip faults. This is controlled by the internal structure of faults. It is concluded that the more complicated the fault structure is, the more significant the effects will be. If there is a deformation band, it will hinder the cross fault migration due to the common feature of two to four orders of magnitude reduction in permeability. Otherwise, hydrocarbons tend to accumulate in the up-dip structure under the control of buoyancy. Further research on the internal fault structure should be emphasized.

关键词： Geologic chromatographic effect fault intersection zone differential hydrocarbon migration and accumulation superimposed basin Tazhong area Tarim Basin

Spatial-Temporal Changes in Grain Production, Consumption and driving mechanism in China

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Journal of Integrative Agriculture 2013年第2期12卷 374-385页

作者： XU Shi-wei WU Jian-zhai SONG Wei LI Zhi-qiang LI Zhe-min KONG Fan-tao Key Laboratory of digital Agricultural Early-Warning Technology Ministry of Agriculture/Agriculture Information Institute Chinese Academy of Agriculture Sciences Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences

The spatial-temporal patterns of grain production and consumption have an important influence on the effective national grain supply on condition of tight balance in the total grain amount in China. In this paper, we analyze the spatial-temporal pattems of grain production, consumption and the driving mechanism for their evolution processes in China. The results indicate that both gravity centers of grain production and consumption in China moved toward the northern and eastern regions, almost in the same direction. The coordination of grain production and consumption increased slightly from 1995 to 2007 but decreased from 2000 to 2007. There is a spatial difference between the major districts of output increase and the strong growth potential in grain consumption, which indicates an increasing difficulty in improving the regional coordination of grain production and consumption. The movement of the gravity center of grain production is significantly correlated with regional differences in grain production policy, different economic development models, and spatial disparity of land and water resource use. For grain consumption, the main driving factors include rapid urbanization, the upgrade of food consumption structure, and distribution of food industries.

关键词： grain production grain consumption gravity center driving mechanism

Synthesis and Crystal Structure of Complex: [Co（cdm）2（H2O）4].2H2O （cdm=Carbamyldicyanomethanide Anion）

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Chinese Journal of Structural Chemistry 2002年第2期 178-181页

作者： SHI Jing-min②1 YIN Hai-Liang1 SUN Li-Jing1 YU Wen-Tao2 XU Wen1 ZHAO ming-Gen3 1(department of Chemistry, Shandong Normal University, Jinan 250014, China) 2(Institute of Crystal matrials, Shandong University, Jinan 250010, China) 3(department of Che department of Chemistry， Shandong Normal University， Jinan 250014， China Institute of Crystal matrials， Shandong University， Jinan 250010， China department of Chemistry， Xinzhou Normal Institute， Xinzhou 034000， China

mononuclear complex [Co(cdm)2(H2O)4]?H2O was synthesized by sodium carbamyldicyanomethanide (Nacda) and cobalt perchlorate. The crystal belongs to monoclinic system, space group P21/n with a = 9.366(3), b = 7.392(3), c = 12.039(4)? = 108.335(4)? V = 791.2(5)?, Z = 2, mr (C8H16CoN6O8) = 383.2, dc = 1.608 g/cm3, F(000) = 394, = 1.135 mm-1, = 0.71073 ? The structure was refined to R = 0.0240 and wR = 0.0632 for 1267 observed reflections (I > 2(I)). The cobalt(II) atom in the complex is coordinated by two nitrile-nitrogen atoms and four oxygen atoms of H2O, which forms a slightly distorted coordination octahedron around the cobalt(II) ion. The mononuclear complexes are connected by hydrogen bondings and in the crystal there exists a cavity where the uncoordinated H2O molecules are trapped.

关键词： synthesis crystal structure cobalt complex

LARGE TImE BEHAVIOR OF SOLUTIONS TO NEWTONIAN FILTRATION EQUATIONS WITH SOURCES

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Acta mathematica Scientia 2010年第3期30卷 968-974页

作者：王路生尹景学王泽佳 department of mathematics Jilin University department of mathematics South China Normal University

This article is concerned with large time behavior of solutions to the Neumann or dirichlet problem for a class of Newtonian filtration equations ｜x｜λ＋Эt^-Эu=div（｜x｜^k∨u^m）＋｜x｜λ＋ku^p with 0 〈 m 〈 1,p 〉 1,λ≥0, k ∈ R. An interesting phenomenon is that there exist two thresholds k∞ and kl for the exponent k, such that the critical Fujita exponent pc for p exists and is finite if k E （k∞, k1）, otherwise, pc is infinite or does not exist.

关键词： Newtonian filtration equation critical exponent exterior problem Thresh -old

decomposition of different Litter Fractions in a Subtropical Bamboo Ecosystem as Affected by Experimental Nitrogen deposition

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Pedosphere 2011年第6期21卷 685-695页

作者： TU Li-Hua HU Hong-Ling HU Ting-Xing ZHANG Jian LIU Li LI Ren-Hong dAI Hong-Zhong LUO Shou-Hua Sichuan Provincial Key Laboratory of Forestry Ecological Engineering College of Forestry Sichuan Agricultural University Xingkang Road 46 Ya'an 625014 (China) maize Research Institute Sichuan Agricultural University Ya'an 625014 (China) Sichuan Forestry Inventory and Plan Institute Chengdu 610081 (China)

As an important component of the global carbon （C） budget, litter decomposition in terrestrial ecosystems is greatly affected by the increasing nitrogen （N） deposition observed globally. We hypothesized that different litter fractions derived from a single tree species may respond to N deposition differently depending on the quality of the litter substrate. To test the hypothesis, a two-year field experiment was conducted using the litterbag method in a Pleioblastus amarus plantation in the rainy region of Southwest China. Four N treatment levels were applied： control （no N added）, low-N （50 kg N ha-1 year-1）, medium-N （150 kg N ha-a year-1）, and high-N （300 kg N ha-1 year-l）. We observed different patterns of mass loss for the three P. amarus litter fractions （leaves, sheaths, and twigs） of varying substrate quality in the control plots. There were two decomposition stages with different decay rates （fast rate in early stages and slow rate in the later stages） for leaves and sheaths, while we did not observe a slower phase for the decay of twigs during the 2-year study period. The annual decomposition rate （k） of twigs was significantly lower than that of leaves or sheaths. Addition of N slowed the decomposition of leaves and twigs in the later stages of decomposition by inhibiting the decay of lignin and cellulose, while addition of N did not affect the mass loss of sheaths during the study period. In the decomposition of all three litter fractions, experimental N deposition reduced the net N accumulation in the early stages and also decreased the net N release in the later stages. The results of this study suggest that litter substrate quality may be an important factor affecting litter decomposition in a bamboo ecosystem affected by N deposition.

关键词： decomposition rate litter substrate N dynamics plant biomass Pleioblastus amarus