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The Rewriting Algorithm for Disjunctive Queries between Peer Ontologies

The Rewriting Algorithm for Disjunctive Queries between Peer...

2007年第三届语义和知识网格国际会议(Third International Conference on Semantics,knowledge,and Grid)(SKG 2007)

作者： Biao Qin Shan Wang Dept. of Computer Science Renmin University of China Beijing 100872 China Key Laboratory of Data Engineering and Knowledge Engineering Ministry of EducationBeijing 100872 China

We study the problem of answering queries given a set of mappings between peer ontologies. In addition to the schema mapping between peer ontologies, there are axioms to give constraints to classes and properties. We propose a set of rules to build graphs for the axioms. Because the axioms have different properties, the generated graphs are classified into four sets. In each peer, its RDF/OWL query languages can support regular expressions. If it wants to be transitive along semantic paths in peer knowledge management systems, we must rewrite conjunctive and disjunctive queries between peers. Because conjunctive queries are well-understood, we focus on a novel algorithm to rewrite disjunctive queries along semantic paths based on the graphs. For all atoms of a disjunctive query, we consider its union as a set and find the maximum rewritings over peers through a graphical way. Finally we do extensive simulation experiments. The simulation results show our algorithm can generate more rewritings than the naive rewriting algorithm at each distance.

关键词： Ontologies Resource description framework OWL Terminology database languages Connectors knowledge management Extraterrestrial measurements Computer science Laboratories

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Enhancing disease resistances of Super Hybrid Rice with four antifungal genes

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Science China(Life Sciences) 2007年第1期50卷 31-39页

作者： ZHU HuaChen1. XU XinPing1. XIAO GuoYing2,3, YUAN LongPing2 & LI BaoJian1.1.Biotechnology Research Center, key {1. of Gene engineering of ministry of education, Sun Yat-sen University, Guangzhou 51.275, China 2 China National Hybrid Rice R&D Center, Hunan Hybrid Rice Research Center, Changsha 41.1.5, China 3 Institute of Subtropical Agriculture, the Chinese Academy of Sciences, Changsha 41.1.5, China 1. Biotechnology Research Center Key Laboratory of Gene Engineering of Ministry of Education Sun Yat-sen University Guangzhou 510275 China 2. China National Hybrid Rice R&D Center Hunan Hybrid Rice Research Center Changsha 410125 China 3. Institute of Subtropical Agriculture the Chinese Academy of Sciences Changsha 410125 China

A plant expression vector harboring four antifungal genes was delivered into the embryogenic calli of ‘931.’, an indica restorer line of Super Hybrid Rice, via modified biolistic particle bombardment. Southern blot analysis indicated that in the regenerated hygromycin-resistant plants, all the four anti-fungal genes, including RCH1., RAC22, β-Glu and B-RIP, were integrated into the genome of ‘931.’, co-transmitted altogether with the marker gene hpt in a Mendelian pattern. Some transgenic R1.and R2 progenies, with all transgenes displaying a normal expression level in the Northern blot analysis, showed high resistance to Magnaporthe grisea when tested in the typical blast nurseries located in Yanxi and Sanya respectively. Furthermore, transgenic F1.plants, resulting from a cross of R2 homo-zygous lines with high resistance to rice blast with the non-transgenic male sterile line Peiai 64S, showed not only high resistance to M. grisea but also enhanced resistance to rice false smut (a disease caused by Ustilaginoidea virens) and rice kernel smut (another disease caused by Tilletia barclayana).

关键词： Super Hybrid Rice multi-gene transformation rice blast rice false smut rice kernel smut anti-fungi disease resistance

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2DCMA： An Effective Maintenance Algorithm of Materialized Views in Peer data Management Systems

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Journal of Computer Science & Technology 2006年第4期21卷 503-512页

作者：覃飙王珊杜小勇 School of Information Renmin University of China Beijing 100872 P.R. China Key Laboratory of Data Engineering and Knowledge Engineering Ministry of Education Beijing 100872 P.R. China

Update management is very important for data integration systems. So update management in peer data management systems （PDMSs） is a hot research area. This paper researches on view maintenance in PDMSs. First, the definition of view is extended and the peer view, local view and global view are proposed according to the requirements of applications. There are two main factors to influence materialized views in PDMSs. One is that schema mappings between peers are changed, and the other is that peers update their data. Based on the requirements, this paper proposes an algorithm called 2DCMA, which includes two sub-algorithms： data and definition consistency maintenance algorithm% to effectively maintain views. For data consistency maintenance, Mork＇s rules are extended for governing the use of updategrams and boosters. The new rule system can be used to optimize the execution plan. And are extended for the data consistency maintenance algorithm is based on the new rule system. Furthermore, an ECA rule is adopted for definition consistency maintenance. Finally, extensive simulation experiments are conducted in SPDMS. The simulation results show that the 2DCMA algorithm has better performance than that of Mork＇s when maintaining data consistency. And the 2DCMA algorithm has better performance than that of centralized view maintenance algorithm when maintaining definition consistency.

关键词： view maintenance peer data management system schema mapping ECA rule

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Study on the electric double layer of a cylindrical reverse micelle with functional theoretical approach

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Science China Chemistry 2006年第3期49卷 219-224页

作者： WANG Zhengwu1.2, GUO Baomin2, ZHANG Gexin1.& YU Huixin1.1. key {1. of Industrial Biotechnology of ministry of education, Southern Yangtze University, Wuxi 21.036, China 2. School of Chemical and Material engineering, Southern Yangtze University, Wuxi 21.036, China 1. Key Laboratory of Industrial Biotechnology of Ministry of Education Southern Yangtze University Wuxi 214036 China 2. School of Chemical and Material Engineering Southern Yangtze University Wuxi 214036 China

The iterative method in functional analysis is applied to looking for asolution of the Poisson-Boltzmann equation in order to describe the problems of the distribution ofthe potentials in the electric double layer (EDL) inside the water pool for a cylindrical inversemicelle. Potentials as a function of the position of a particular point in EDL are computed, whichdisplay a quantitative agreement with those from earlier calculation of Debye and Huckel in the caseof low potentials. But it is also shown that in the higher-potential range the iterativecalculations can give more accurate results. These results indicate the utility of this functionalanalysis technique in the description of the properties of EDL for a cylindrical inverse micelle.

关键词： cylindrical reverse micelle, electrostatic double layer, Poisson-Boltzmann equation, functional analytic theory.

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The effect of decreasing alkalinity on microbial community dynamics in a sulfate-reducing bioreactor as analyzed by PCR-SSCP

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Science China(Life Sciences) 2006年第4期49卷 370-378页

作者： REN Nanqi1. ZHAO Yangguo1. WANG Aijie1. GAO Chongyang2, SHANG Huaixiang1. LIU Yiwei1.& WAN Chunli1.1. School of Environmental and Municipal engineering, Harbin Institute of Technology, Harbin 1.0090, China 2. {1. laboratory of Forest Plant Ecology, ministry of education, Northeast Forestry University, Harbin 1.0040, China 1. School of Environmental and Municipal Engineering Harbin Institute of Technology Harbin 150090 China 2. Key Laboratory of Forest Plant Ecology Ministry of Education Northeast Forestry University Harbin 150040 China

PCR-single-strand conformation polymorphism (SSCP) and Southern blotting tech-niques were adopted to investigate microbial community dynamics in a sulfate-reducing bioreactor caused by decreasing influent alkalinity. Experimental results indicated that the sulfate-removal rate approached 87% in 25 d under the conditions of influent alkalinity of 4000 mg/L (as CaCO3) and sul-fate-loading rate of 4.8 g/(L·d), which indicated that the bioreactor started up successfully. The analy-sis of microbial community structure in this stage showed that Lactococcus sp., Anaerofilum sp. and Kluyvera sp. were dominant populations. It was found that when influent alkalinity reduced to 1.00 mg/L, sulfate-removal rate decreased rapidly to 35% in 3 d. Then influent alkalinity was increased to 3000 mg/L, the sulfate-removal rate rose to 55%. Under these conditions, the populations of Dysgo-nomonas sp., Sporobacte sp., Obesumbacterium sp. and Clostridium sp. got to rich, which predomi-nated in the community together with Lactococcus sp., Anaerofilum sp. and Kluyvera sp. However, when the alkalinity was decreased to 1.00 mg/L, the sulfate-removal rate rose to and kept stable at 70% and populations of Dysgonomonas sp., Sporobacter sp. and Obesumbacterium sp. died out, while some strains of Desulfovibrio sp. and Clostridium sp. increased in concentration. In order to determine the minimum alkalinity value that the system could tolerate, the influent alkalinity was de-creased from 1.00 to 400 mg/L secondly. This resulted in the sulfate-removal rate, pH value and ef-fluent alkalinity dropping quickly. The amount of Petrotoga sp., Prevotella sp., Kluyvera sp. and Neisseria sp. reduced obviously. The result data from Southern blotting indicated that the amount of sulfate-reducing bacteria (SRBs) decreased with influent alkalinity dropping. Analysis of the microbial community structure and diversity showed that the SRBs populations were very abundant in the in-oculated activated sludge and the al

关键词： alkalinity, community dynamics, PCR-single-strand conformation polymorphism (SSCP), Southern blotting, sulfate-reducing bacterium (SRB), fermentative acidogenic bacterium (FAB).

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Effects of Cu^(2+) on characteristic of SV currents

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Science China Chemistry 2006年第6期49卷 560-564页

作者： ZHANG Liping1.2 & YANG Pin1.1. key {1. of Chemical Biology and Molecular engineering of ministry of education, Institute of Molecular Science, Shanxi University, Taiyuan 030006, China 2. Institute of Environment Science, Taiyuan University of Science and Technology, Taiyuan 030024, China 1. Key Laboratory of Chemical Biology and Molecular Engineering of Ministry of Education Institute of Molecular Science Shanxi University Taiyuan 030006 China 2. Institute of Environment Science Taiyuan University of Science and Technology Taiyuan 030024 China

Applying the patch-clamp technique to vacuoles from Radish we studied the effects of Cu2+ on Slow Vacuolar (SV) current’s characteristic. Our results show that Cu2+ in bath solution at higher concentration inhibits SV currents and the percentage of inhibition increases with increasing concentration and changes with different voltage. When at lower concentration, Cu2+ significantly promotes the SV currents and the promotion ratio decrease with increasing voltage. At the same time, the time constants of activation become lesser after adding Cu2+. These results show that there may be some Cu2+ binding sites on SV channels and binding to which can change SV current’s characteristic.

关键词： the patch-clamp technique, vacuolar, Cu2+, SV channel.

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Formation of the Permian basalts and implications of geochemical tracing for paleo-tectonic setting and regional tectonic background in the Turpan-Hami and Santanghu basins,Xinjiang

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Science China Earth Sciences 2006年第6期49卷 584-596页

作者： ZHOU Dingwu1.2, LIU Yiqun1.2, XING Xiujuan1. HAO Jianrong1. DONG Yunpeng1.& OUYANG Zhengjian1.1. key {1. of Continental Dynamics, ministry of education, Northwest University Department of Geology, Northwest University, Xi’an 71.069, China 2. Geoinformation Science & engineering College, SDUST, Qingdao 26651., China 1. Key Laboratory of Continental Dynamics Ministry of Education Northwest University Xi’an 710069 China 2. Geoinformation Science & Engineering College SDUST Qingdao 266510 China 3. Department of Geology Northwest University Xi’an 710069 China

The Turpan-Hami and Santanghu basins are the late Paleozoic-Mesozoic-Cenozoicreworked intracontinental basins that superposed on the folded basement of the Paleozoic orogenicbelt. ^(40)Ar/^(39)Ar geochronological study of the basalts developed in the basins reveals that theformation period is Permain (293—266 Ma). From geochemical comparison of the basalts, theSantanghu basalts exhibit a strong depletion in Nb and Ta, and a selective enrichment in HFSE,reflecting that the source region is influenced by the subducted components related to subduction ofthe ancient oceanic crust and characterized with ''lagged arc volcanic rocks''. In contrast, theTurpan-Hami basalts show a slight depletion in Nb and Ta, high Th/Ta ratio, similar to the basaltsformed in an intracontinental ex-tensional zone or in an initial rift. Combined with the formationperiod of the ophiolite and ophiolite melange zones and regional magmatic activities occurring onthe post-orogenic extensional background in northern Xinjiang, it can be inferred from thesegeochemical characteristics that the tectonic background for forming the Turpan-Hami and Santanghubasins is closely related to the regional extension after the continent-continent collisionalorogeny. The basalts of the two basins came from different sources on the post-orogenic extensionalbackground of the similar basin-forming dynamics. Although the settings are all intracontinentalrift, the source for the Santanghu basalts is obviously subjected to the metasomatism of thesubducted components, implying the existence of the previous subduction.

关键词： Xinjiang, Tu-Ha basin, Santanghu basin, basalt, postorogeny, tectonic setting, extensional background.

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Microwave-assisted reaction of peptide formation by amino acid with phosphate:Exploration of the most possible channels for the origin of life

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Science China Chemistry 2006年第4期49卷 351-356页

作者： HU Rong1. TIAN Jinping2 & YIN Yingwu2,3 1. College of Chemistry & Environment Protection engineering, Southwest University for Nationalities, Chengdu 61.041. China 2. TH-UNIS Insight Co., Ltd., Beijing 1.0085, China 3. {1. laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology, ministry of education, Department of Chemistry, Tsinghua University, Beijing 1.0084, China 1. College of Chemistry & Environment Protection Engineering Southwest University for Nationalities Chengdu 610041 China 2. TH-UNIS Insight Co. Ltd. Beijing 100085 China 3. Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology Ministry of Education Department of Chemistry Tsinghua University Beijing 100084 China

Microwave-assisted reaction of peptide formation by amino acids with phosphate was studied. The results showed that the products were a mixture of peptides containing dipeptide, oc- tapeptides and cyclic peptides, which could be obtained in a short time. Polyphosphate was also produced synchronously by the intermolecular condensation of phosphate. The polymerization de- gree reached 99% (pyrophosphate 64%, trimetaphosphate 35%) after 2 h at 200℃ under microwave irradiation. The intermediates of the mixed anhydrides formed by the intermolecular condensation of phosphates and glycin were determined by ESI-MS. Peptides were also produced by the reaction of amino acids with trimetaphosphate in aqueous solution. The conversion degree of valine reached 46.5% even at room temperature. The cyclic process of peptide formation and phosphate polymeri- zation, regeneration and utilization in amino acids-phosphate system under microwave irradiation was detected and proved. Peptides could be continually formed only by inputting energy into this system. The above recycle may be the most possible process for primitive peptide formation in the origin of life.

关键词： microwave, phosphate, amino acid, peptide, origin of life.

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Study on the cluster of floating dross before nucleating during hot-dipping process

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Science China Chemistry 2005年第1期48卷 83-88页

作者： WEI Yunhe1. ZHANG Changqiao1. QIN Jingyu2 & LIU Chengbu1.1. School of Chemistry and Chemical engineering, Shandong University, Jinan 2501.0, China 2. The {1. laboratory of Liquid Structure and Heredity of Materials of ministry of education, Shandong University, Jinan 250061. China 1. School of Chemistry and Chemical Engineering Shandong University 250100 Jinan China 2. The Key Laboratory of Liquid Structure and Heredity of Materials of Ministry of Education Shandong University 250061 Jinan China

During hot-dipping in molten Zn-55Al, the forming of “floating” dross is closely re- lated with the interaction between the Al and the Fe atoms. Utilizing the thita-thita X-ray diffraction and the Percus-Yevick hard sphere model, this paper investigates the structure of molten Al3Fe that is an approximant of partial melt in practical Zn-55Al alloy melt. It is found that in the melt there exist clusters that resemble the structure of intermetallic compound Al3Fe. The strong in- teraction between Al and Fe atoms is also indicated by the deficiency of the coordination number from 1. and the shrinkage of averaged atomic diameter. Based on such information, it is specu- lated that in the molten Zn-55Al, with the accumulation of Fe, Al3Fe-like clusters form with priority, then grow into dross. On the other hand, after deflating of the effective hard sphere diameter of pure Al atom and enlarging that of the pure Fe atom, the modified model can achieve reasonable fit to the experimental structure factor. Hard sphere modeling also gave a good estimation of the mass density 3.65 g/cm3 of liquid Al3Fe alloy at 1.50℃. Compared with the density of 3.7 g/cm3 of Zn-55Al, the reason for dross floating is satisfactorily understood.

关键词： hot-dipping, dross, Al3Fe alloy, molten structure, P-Y model.

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Dynamic behavior of polymer surface and the time dependence of contact angle

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Science China Chemistry 2005年第6期48卷 553-559页

作者： WANG Xinping1. CHEN Zhifang1.& SHEN Zhiquan2 1. key {1. of Advanced Textile Materials and Manufacturing Technology of education ministry, Department of Applied Chemistry, Zhejiang Institute of Science and Technology, Hangzhou 31.033, China 2. Department of Polymer Science and engineering, Zhejiang University, Hangzhou 31.027, China 1. Department of Applied Chemistry Zhejiang Institute of Science and Technology Key Laboratory of Advanced Textile Materials and Manufacturing Technology of Education Ministry 310033 Hangzhou China 2. Department of Polymer Science and Engineering Zhejiang University 310027 Hangzhou China

Time-dependent contact angles were measured by depositing sessile drops of wa-ter on the polymer surfaces and monitoring the drop shape as a function of time. It was found that contact angles decreased sharply with contact time and the equilibrium contact angle was finally attained after a certain time. Values of starting (θ s) and equilibrium contact angles (θ e) obtained by the sessile drop method depend on polymer properties. The Wilhelmy plate technique was used to measure advancing and receding contact angles. The variations of starting (θ s) and equilibrium contact angles (θ e), advancing (θ a) and receding contact angles (θ r) have been studied on the oxidized surface of polymers containing polybutadiene block to explore the cause of time-dependence in contact angle measurement and the meaning of θ s and θ e. The results showed the linear relationships between starting (θ s) and advancing contact angles (θ a), the equilibrium (θ e) and receding contact angles (θ r). The similar relationship was also established between the contact angle hysteresis (θ a?θ r) and differences (θ s ?θ e) in starting contact angles and equilibrium contact angles. Therefore, time-dependence in contact angle measurement was mainly attributed to the surface reconstruction when water drops were deposited on polymer surfaces. The starting contact angle was contributed by the hydrophobic component on polymer surface and the equilibrium contact angle mainly by the hydrophilic component of polymer. These results not only demonstrated the interdependency between two contact angle measurements, the sessile drop method and the Wilhelmy plate technique, but also provided the experimental evidence to explain the cause of time-dependent contact angle. This may also provide a new method to study dynamic behavior of polymer surface.

关键词： contact angle, surface dynamic behavior, polymer surface, dynamic contact angle, time-dependence.

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