基于基库的多实化视图增量维护算法

基于基库的多实化视图维护将基库集作为多个实化视图的辅助视图集保存在集成端。当信息源发生变化时,基库随着更新,同时触发多实化视图的更新与维护。在保存基库的情况下,多实化视图的维护无需访问信息源就可完成,是多实化视图的自维护方式。

基于多实化视图增量维护的基库生成算法

数据仓库的维护是数据仓库应用中的一个十分重要的问题,近几年产生了很多的维护算法。已有的维护算法多是针对单个实化视图的维护;或只针对简单SPJ视图的维护;或只针对聚集函数的维护;而实际的数据仓库大多是由包含聚集函数的多个实化视图组成。因此综合考虑包含聚集函数的多个实化视图的维护问题是必然的。文章正是在此情况下提出了一种基于多实化视图增量维护的基库生成算法,在《基于基库的多实化视图增量维护算法》中提出了包含聚集函数的多实化视图的维护算法。

北京市基础交通尾气数据库系统的开发及应用

OEM是最新的基于车辆实际行驶路况的车载尾气检测系统,介绍了利用OEM测试北京市公路交通车辆尾气排放数据,开发了北京市基础交通尾气数据库系统(BFTEDS)。叙述了系统的开发思想、基本结构及实现功能,提出了北京市基础交通尾气数据库系统的应用前景。

从基库尤民族主义到泛非民族主义——肯雅塔早期政治思想述评

乔莫·肯雅塔出生于肯尼亚基库尤族的普通农民家庭,并从一个牧羊娃成长为基库尤民族主义者。他为谋求基库尤人的民族权益而去往欧洲。在那里,他受到各种影响,尤其是左翼思潮的影响,从而突破地方民族主义的狭隘界限,成为了为“争取一个自由的非洲”而斗争的泛非民族主义者,并撰写出了《面对肯尼亚山》这一泛非民族主义的名著。肯雅塔的这种思想演变具有进步性和激进的反帝反殖色彩,并为他后来领导肯尼亚人民争取民族独立奠定了思想基础。但是,肯雅塔并不主张建立一个泛非国家,他的泛非民族主义的核心和整个政治思想的主流仍是肯尼亚民族主义。

库登霍夫-卡莱基“泛欧”联合思想中的英国观

第一次世界大战后,卡莱基认为,区域化时代来临,英帝国蜕变成为独立的、与大陆欧洲平行共存的区域共同体。从"小德意志"统一的历史经验出发,卡莱基认识到,英国肯定不会主动放弃帝国共同体,加入到"欧洲"大家庭当中来,相反,它随时准备为了英帝国去牺牲"欧洲"的利益。因此,必须排除英国,坚定不移地走"小欧洲"联合的道路。30年代初,英帝国贸易区的诞生与英国拒绝参加"欧洲"计划,都直接、充分地说明卡莱基对英帝国一体的判断是正确、客观的,其排除英国的主张是明智、实际的。研究卡莱基的英国观对于我们认识英国与欧洲一体化的关系具有重要的启示作用。

糖基工程酵母表面呈现抗体库的构建及抗真菌β甘露糖型抗体的筛选

目的:通过构建糖基工程酵母表面呈现免疫抗体库,筛选与毕赤酵母表达的禽流感血凝素HA7结合的特异性抗体。方法:利用糖基工程毕赤酵母细胞膜锚定蛋白Sed将人Ig G的Fc段锚定在酵母表面,然后用毕赤酵母表达的HA7免疫小鼠,从小鼠脾脏细胞中扩增抗体轻重链可变区基因构建抗体转化锚定了Fc的糖基工程酵母,构建表面展示免疫抗体库,通过免疫磁珠法筛选与毕赤酵母表达的HA7特异性结合的抗体表达酵母,分析筛选该抗体的特异性结合靶点。结果:构建了多态性良好的抗体表达质粒库,转化糖基工程酵母后筛选得到特异性结合HA7的抗体呈现酵母,Western印迹分析发现该抗体只与糖基化的HA7结合而不与切除糖链后的HA7结合,说明抗体结合区域在HA7的糖链上,进一步实验发现该抗体不与α甘露糖型和哺乳动物复杂型糖型结合,通过β甘露糖苷酶切研究发现抗体结合靶点为酵母表达HA7糖链上的β甘露糖。结论:利用糖基工程酵母构建抗体库,筛选得获得了抗真菌β甘露糖的抗体,动物实验发现抗体具有中和活性。

数据仓库的联机维护与下查

提出了一种三层数据仓库体系结构，引入了“数据仓库基库”概念，不仅使得传统数据库能够更容易地融入数据仓库系统，而且增强了整个系统的伸缩性．在此基础上，提出了３ＶＷＱ（Ｔｈｒｅｅ－Ｖｅｒｓｉｏｎ ＷｉｔｈｏｕｔＱｕｉｅｓｃｉｎｇ）算法来解决数据仓库的联机维护问题及其对下查的支持．该算法采用版本控制和补偿思想来协调数据库和数据仓库之间的数据更新。

贮库组成对青蒿琥酯经皮渗透的影响

目的 :通过对青蒿琥酯在不同贮库基质中的经皮渗透研究 ,确定影响其经皮渗透的主要因素 ,为青蒿琥酯透皮吸收制剂的研制提供有效数据。方法 :以透皮吸收速率常数和 12h累积渗透量为考察指标 ,应用正交设计追加试验法 ,探讨不同比例组成的IPA/Water/IPM、药物浓度及 pH值对青蒿琥酯经皮渗透影响。 结果 :药物浓度和pH值对青蒿琥酯的经皮渗透产生主要影响。结论 :适当组成的贮库基质可较好地促进青蒿琥酯的经皮渗透 ,若对其进一步研究 ,青蒿琥酯有望制成透皮吸收制剂。

模拟状态下高尔夫球场果岭区域土壤氮磷浸出物对铁岗水库水质影响研究

通过采集高尔夫球场即将淹没的果岭土壤进行实验室条件下的模拟库基样品试验,对水库扩容后蓄水初期水质的变化情况进行了研究。结果表明:库水所含主要成分p H、高锰酸钾盐指数、总氮、总磷、氨氮和硝酸盐氮分别为7.4(mg/L)、30.8(mg/L)、1.16(mg/L)、1.189(mg/L)、0.21(mg/L)和0.11(mg/L);果岭20 cm土层库基土样p H、有机质、硝酸盐氮、氨态氮和有效磷分别为6.41(mg/kg)、10.29(mg/kg)、25.48(mg/kg)、25.76(mg/kg)和140.77(mg/kg)。现有库基成分会改变库水高锰酸钾盐指标的升高。库水本身的总磷和总氮含量就严重超标。果岭库基本身的磷氮含量也很高。浸泡后果岭库基土样对降低浸出物总磷的严重超标起到了对冲的作用,致使总磷含量大为降低。

可溶岩地区抽水蓄能电站主要工程地质问题探讨

为适应新型能源体系构建的需要,抽水蓄能电站规划和建设在全国普遍展开,有相当数量的站点布置在可溶岩地区。与常规水电站不同,抽水蓄能电站对水库渗漏、地下洞室围岩质量等要求更高,因而对工程地质勘察工作也提出了较高的要求。在总结抽水蓄能电站建设和工程地质勘察经验的基础上,针对可溶岩地区抽水蓄能电站建设面临的水库岩溶渗漏、岩溶库基稳定、地下水顶托、岩溶洞段地下洞室围岩稳定等主要工程地质问题进行了探讨,可供相关人员参考。

论时空体对小说世界构建的作用:以小说《库科茨基医生的病案》为例

在乌利茨卡娅的小说《库科茨基医生的病案》里,宏大的整一时空体内存在着潜隐危机与转折的关键时空体,作者在其中巧妙地融合空间和时间,结合个人生活与历史事件,使小说情节自然展开,同时动态地刻画出各具特点、栩栩如生的人物形象,让人物由静态到动态,由平面到立体。小说赋予人物时代的特点,并使理解事件获得了新的角度,将新的哲学思考和价值因素注入时空,构建出确切时空体中微缩的小说世界。

Construction and Characterization of a Bacterial Artificial Chromosome Library for Triticum boeoticum

A bacterial artificial chromosome library has been constructed for Triticum boeoticum Boiss (A bA b) using the bacterial artificial chromosome (BAC) vector pECBAC1. The library consists of about 170 000 clones. A random sampling analysis of 200 BAC clones indicates that the average insert size is 104 kb. Based on the genome size of T. boeoticum, the library is about three times as large as T. boeoticum haploid genome (5 600 Mb). Screening the BAC library with cpDNA sequence psbA gene and mtDNA sequence atp6 gene as probe shows that contamination of the library with chloroplast and mitochondrial clones is less than 1%. The library will be a useful platform in gene clone and genomic research of wheat.

Study on Cloning and Polymorphism of Porcine Adiponectin Promoter

[ Objective] The aim of this study was to provide a basis for study on adiponectin as a candidate gene for fat deposition. [ Method] The promoter sequence of adiponectin was obtained by porcine BAC library screening and primer-walking method. The polymorphisms of adiponectin promoter from 290 pigs, including 5 breeds of Lantang pig, Large spotted pig, Large white pig, Landrace and Duroc, were analyzed with PCR-RFLP. [ Result] At SNP site of adiponectin 5＇-flanking region -1 010 bp （G/A）, GG genotype frequency in Chinese indigenous pigs was significantly higher than that in exotic pigs. At SNP site of adiponectin 5＇-flanking region -394 bp （T/C）, the genotype distribution of Chi- nese indigenous pigs was abundant, while no CC genotype was detected in exotic pigs, and T allele frequency was higher in exotic pigs. [ Conclusion] SNP site mutation of - 1 010 bp （G/A） may lead to changes of the gene transcription level, while SNP site of -394 bp （T/C） properly has no relationship with gene transcription level and fat deposition.

Isolation and Characterization of Microsatellites in Snap Bean

The objectives of this study were to isolate and characterize microsatellites from a heat tolerant variety of snap bean (Phaseolus vulgaris L.) in order to generate polymorphic genetic markers linked to quantitative trait loci for heat tolerance. A genomic library contained 400-800 bp inserts was constructed and screened for the presence of (GA/CT) n and (CA/GT) n repeats. The proportion of positive clones yielded estimated of 3.72×10 4 such dinucleotide repeats per genome, roughly comparable to the abundance reported in other eukaryotic genomes. Twenty_six positive clones were sequenced. In contrast to mammalian genomes, the (GA/CT) n motif was much more abundant than the (CA/GT) n motif in these clones. The (GA/CT) n repeats also showed longer average repeat length (mean n =10.4 versus 6.5), suggesting that they are better candidates for yielding polymorphic genetic markers in the snap bean genome.

Screening an Na^+/H^+ Antiporter Gene from the Halophiles Colonizing in the Dagong Ancient Brine Well of Zigong City,China

[Objective] This study aimed to screen an Na＋/H＋ antiporter gene from the halophiles colonizing in the Dagong Ancient Brine Well in Zigong City, China, and then analyze the gene structure and properties of the protein encoded by this gene. [Method] Metagenomic DNA libraries of halophiles from the Dagong Ancient Brine Well were used for screening genes with Na＋/H＋ antiporter activity in antiporter-defi- cient E. coil KNabc strain by functional complementation. Then the start codon, stop codon, ORF, -35 region, -10 region and SD sequence of Na~/H＋ antiporter gene, as well as the molecular weight, isoelectric point, hydrophobic region, transmembrane domain, phyletic evolution and salt resistance of protein encoded by the gene were investigated. [Result] A new Na＋/H＋ antiporter gene m-nha was obtained, which ,ren- dered the antiporter-negative mutant E. coil KNabc cells with both the resistance to Na＋ and the ability to grow under alkaline conditions. [Conclusion] The structure and amino acid sequence of M-Nha was different from the previously reported Na＋/H~ antiporters, and the m-nha gene disclosed from the Dagong Ancient Brine Well was identified as a novel Na＋/H＋ antiporter gene. This study was significant not only in helping us understand the salt tolerance of halophiles in ancient brine wells and develop and utilize the genes resource, but also in exploring new salt-tolerant genes.

Fluorescence molecular imaging system and fusion algorithm based on 2CCD camera

Infrared and visible light images can be obtained simultaneously by building fluorescence imaging system,which includes fluorescence excitation,images acquisition,mechanical part,image transmission and processing section.This system studied the 2charge-coupled device(CCD)camera(AD-080CL)of the JAI company.Fusion algorithm of visible light and near infrared images was designed for the fluorescence imaging system with wavelet transform image fusion algorithm.In order to enhance the fluorescent moiety of the fusion image,the luminance value of the green component of the color image was changed.And using microsoft foundation classes(MFC)application architecture,the supporting software system was bulit in VS2010 environment.

A Cosmid Library Constructed to the Elite Rice Cultivar “Minghui 63”

A genomic DNA library was constructed to the elite rice cultivar “Minghui 63” using the cosmid SuperCos1 as the vector. The library consisted of 45000 clones with average insert size about 40 kb. It was estimated that this library had a capacity of 4.2 times equivalent of the haploid genome of rice.

Cloning of Novel Tumor Metastasis-Related Genes from the Highly Metastatic Human Lung Adenocarcinoma Cell Line Anip973

A cDNA library was successfully constructed from Anip973, a human lung adenocarcinoma cell line with high metastatic potential. NIH3T3 cells were stably transfected using this cDNA library and screened for morphological changes in a soft agar assay. Genomic DNA was isolated from putative clones and the integrated sequence was retrieved by PCR and sequencing. Three known genes, ribosomal protein L23, hypothetical protein FLJ22104, and serine protease inhibitor, kazal type 6 and a number of 5＇-terminally truncated sequences were identified. Furthermore, cells transfected with ribosomal protein L23 was highly invasive compared with the empty vector as control （P 〈 0.02）. These results indicate that the expression cloning of cDNA libraries in NIH3T3 cells and subsequent screening for loss of contact inhibition in soft agar is a viable tool for identifying tumor-related genes and ribosomal protein L23 gene plays a role in cell movement and metastasis.

Molecular Cloning and Sequence Analysis of Class Ⅱ Chitinase Gene in Leymus chinensis

[ Objective] The aim of this study was to clone Class Ⅱ chitinase gene in Leymus chinensis grown in saline land in Heilongjiang Province and analyze its sequence, which provided a foundation for further study on the biological function and application of chitinasa gene. [ Method] cDNA library of Leymus chinensis leaves were constructed, and its DNA sequence was determined or analyzed, while the homology of chitinasa gene and amino acid sequence was compared with that in GenBank. [ Result] One full length cDNA fragment with length of 996 bp was cloned from cDNA library of Leymus chinensis leaves. The length of ORF was 768 bp encoding 225 amino acids （GenBank accession number： EU344908）. The encoding products lacked CBD and C-terminal extension region from the view of structure, but had structural characters of Class Ⅱ chitinase gene, which indicated that amino acid sequence had high homology compared with Class Ⅱ chitinase gene of rye and wheat. The constructed recombinant vector pQE-LcChi2 could express a protein of 27 kD through induction, which was consistent with the deduced encoding product of pQE-LcChi2 gene. [ Conclusion] LcChl2 gene is an expression gene, which can express in E. coll.

Bombyx mori Pyridoxal Kinase cDNA Cloning and Enzymatic Characterization

Pyridoxal kinase （PLK） （EC 2.7.1.35） catalyzes the ATP-dependent phosphorylation of pyridoxal, generating pyridoxal-5＇-phosphate （PLP）, an important cofactor for many enzymatic reactions. Bombyx mori, similar to mammals, relies on a nutritional source of vitamin B6 to synthesize PLP. This article describes how a cDNA encoding PLK was cloned from Bombyx mori using the PCR method （GenBank accession number： DQ452397）. The cDNA has an 894 bp open reading frame and encodes a protein of 298 amino acid residues with a molecular mass of 33.1 k.Da. The amino acid sequence shares 48.6% identity with that of human PLK, and it also contains signature conserved motifs of the PLK family. However, the protein is 10 or more amino acids shorter than the PLK from mammals and plants, and several amino acid residues conserved in the PLK from mammals and plants are changed in the protein. The cDNA cloned was expressed successfully in Escherichia coli using the T7 promoter/T7 RNA polymerase expression system, and the crude extracts containing the expressed product were found to have strong PLK enzymatic activity with a value of 30 nmol/min/mg, confirming that the cDNA encodes the functional PLK of Bombyx mori. This is the first identification of a gene encoding PLK in insects.