Elemental composition in the sediments of the Yangtze and the Yellow Rivers and their tracing implication

Elemental compositions in the surface sediments of the Yangtze River and the Yellow River are quite different. The Yangtze River' s sediment is rich in K, Fe, Mg, Al and most of trace elements, and its elemental composition show remarkable spatial variations, whereas the Yellow River s sediment has higher contents of Ca, Na, Sr, Ba, Zr and Hf, and the elemental composition remains relatively stable. The ratios of some elements are also different in the sediments of the two rivers. The elemental composition of the Yangtze River sediment results from widely distributed igneous rocks and complicated source rocks and strong chemical weathering in the Yangtze River catchment basin, while the main provenance of the Yellow River sediment is the Loess Plateau which has dominant influence on the elemental composition, and the intense physical weathering is another controlling factor. The elements such as Cu, Zn, Sc, Ti, Fe, V, Ni, Cr, Co, Li and element ratios such as La/Sc, La/Co, Th/Co, Ti/Zr and Zr/Y can be used as the tracers to distinguish the Yangtze River sediment from the Yellow River s. The tracers can be used in the study of the mixing and distribution of the substances of the two rivers matters in coastal zones of China.     

Conflicting and Harmonizing Between the Black Culture and the White Culture Embodied in Morrison''''s Works and Lecture

In Toni Morrison's works ,there seems to be an eternal theme——the cruelty of black American peoples' fate and the conflict between black culture and white culture. Black culture is in an inferior position for a long time. In Morrison's opinion,the blacks can only survive in the white -dominated world on condition that they hold their own cultural root. And on the other hand,there is another way people should seek,which is to realize tolerance and compatibility of the two cultures. In this speech,Morrison again expounded the relation between the two cultures and expressed her wish that black culture could be admitted and respected by the white people.     

Velocity structure of the crust and uppermost mantle in the boundary area of the Tianshan Mountains and the Tarim Basin

A portable 3-component broadband digital seismic array was deployed across the Tianshan orogenic belt (TOB) to investigate the lithospheric structure. Based on receiver function analysis of the teleseismic P-wave data, a 2-D S-wave velocity profile of the boundary area of the TOB and the Tarim Basin was obtained at the depths of 0--80 km.Our results reveal a vertical and lateral inhomogeneity in the crust and uppermost mantle. Four velocity interfaces divide the crystalline crust into the upper, middle and lower crust. A low velocity zone is widely observed in the upper-middle crust. The depth of Moho varies between 42 and 52 km. At the north end of the profile the Moho dips northward with a vertical offset of 4--6 km, which implies a subduction front of the Tarim Basin into the TOB. The Moho generally appears as a velocity transitional zone except beneath two stations in the northern Tarim Basin, where the Moho is characterized by a typical velocity discontinuity. The fine velocity structure and the deep contact deformation of the crust and upper most mantle delineate the north-south lithospheric shortening and thickening in the boundary area of the TOB and the Tarim Basin, which would be helpful to constructing the geodynamical model of the intracontinental mountain-basin-coupling system.     

Late Tertiary faults and their paleostress along the boundary between the Kuqa Basin and the Tianshan Mountains

Field investigation shows that the boundary between the Kuqa Basin and the Tianshan Mountains can be divided into two sections with the Yanbulak area as the dividing point. In the western section, the Mesozoic strata overlie unconformably on the Paleozoic rocks. The basin-dipping faults developed in both Mesozoic and Paleozoic rocks. The eastern section is characterized by basin-dipping normal faults separating the Paleozoic strata and Tertiary. The brittle structural analysis was carried out along the basin-range boundary. 360 measurements of striations have been obtained at a total of 25 sites. Paleostress reconstruction indicates that the basin-range boundary was in an extensional condition, with some superimposed strike-slip, during the Late Tertiary. The extension could be explained by the vertical block uplift of the Tianshan Mountains.     

NEIT and the JOURNAL NEIT

The Northeast Institute of Technology (NEIT) is located in Shenyang,Liaoning Province——the capital city of China's industrial center. It isknown as an outstanding polytechnical university for its achievements ineducation and scientific research. NEIT has a total of 1, 400 faculty members     

Selection and Verification of the Structural Pattern of the Penstock and Spiral Case of the TGP Power Station

1Patternselectionandver ificationoftheTGPpen stock　TheYangtzeRiverWaterResourcesCommission (CWRC)submittedASub jectReportonthePatternSelectionofthePenstockinthePowerStationoftheThreeGorgesProjectinDecember,1 993,inwhichthearrangementofthepenstockswasdefinitelystated ,twotypesofstructures (internalhydraulicpressurebornesolelybypenstockandinternalhydraulicpressurejointlybornebysteellinerandreinforcedconcrete)proposed ,acomparisonbetweenthetwooptionscomprehensivelyperformed ,andsuggesti…     

The Sun and the Moon in the Old Myths

ＡｎｏｌｄＣｈｉｎｅｓｅｍｙｔｈｓａｙｓｔｈｅｒｅｕｓｅｄｔｏｂｅａｈｏｒｒｉｂｌｅｐｅｒｉｏｄｗｈｅｎｔｅｎｗｉｃｋｅｄｓｕｎｓｃａｍｅｏｕｔｔｏｇｅｔｈｅｒａｎｄｂｕｒｎｔｏｕｔａｌｌｃｒｏｐｓ．Ｔｈｅｎｃａｍｅｔｈｅｇｒｅａｔｈｅｒｏ，ＨｏｕＹｉ，ｗｈｏｋｉｌｌｅｄｎｉｎｅｏｆｔｈｅｓｕｎｓｗｉｔｈｈｉｓｐｏｗｅｒｆｕｌｂｏｗａｎｄａｒｒｏｗｓ．Ｏｆｃｏｕｒｓｅｔｈｅｓｕｎｉｎｔｈｉｓｍｙｔｈｉｓａｈｏｓｔｉｌｅｉｍａｇｅ．Ｉｔｉｓｓｉｎｃｅｔｈｅｔｉｍｅｔｈｅｓｔｏｒｙｃａｍｅｉｎｔｏｂ…     

ization of the age and the tendency to p

irectly the development of regional economy,forefront production and common life of the people.Its education focuses more or less on the teaching,training and research on t     

Subliminal Channels in the NTRU and the Subliminal-Free Methods

The construetion and destruction of subliminal channel are important problems in the information hiding. The subliminal channel can send secret information without notice. Two subliminal-free methods named weak （strong） subliminal-free on public-key cryptosystem （PKC） are proposed in this paper using the combinatorial method. The first method can only free the subliminal information with any minor probability and the second can free all. Moreover, the ＂traitor problem＂ which is same as the model of the subliminal channel in PKC is given. Two subliminal channels are embedded in N-th degree truncated polynomial ring （NTRU） cryptosystem, and their subliminal-free methods are also be obtained by the action of surveillant.     

The Symbolism of the Old Man and the Sea

老人与海是海明威的著名著作,通过它我们可以看到海明威对象征主义的运用。当然,他同时运用了现实主义,比喻意义以及冰山理论等。但是这里仅着重研究象征主义,特别是圣地亚哥的宗教意义以及马洛林的象征意义。     

Co-transformation to tobacco of Cre/lox site-specific recombination system and its precise recombination

For the temporally and spatially regulated expression of the barnase gene in plant, two kinds of plasmids with cre gene and its directly repeat recognition sitesiox from bacteriophage P1 were constructed and co-transformed into tobacco by agrobacterium mediated procedure. The transgenic plants were conformed by PCR analysis. The blocking fragment between the twolox directly repeat sites was excised by Cre protein in the transgenic plant genome. Cloning and sequencing the DNA fragment from the co-transformed plant DNA showed that the precise DNA excision occurred in transgenic tobacco genome directed by Cre/lox site-specific recombination.     

Co-transformation to tobacco of Cre/lox site-specific recombination system and its precise recombination

For the temporally and spatially regulated expression of the barnase gene in plant,two kinds of plasmids with cre gene and its directly repeat recognition sites lox from bacteriophage P1 were constructed and co-transformed into tobacco by agrobacterium mediated procedure.The transgenic plants were conformed by PCR analysis.The blocking fragment between the two lox directly repeat sites was excised by Cre protein in the transgenic plant genome.Cloning and sequencing the DNA fragment from the co-transformed plant DNA showed that the precise DNA excision occurred in transgenic tobacco genome directed by Cre/lox site-specific recombination.     

小鼠Bpi条件基因打靶载体的构建和鉴定

目的构建小鼠Bpi条件基因打靶载体,为建立Bpi条件基因打靶小鼠模型和深入研究Bpi基因功能奠定基础。方法采用Cre/LoxP系统,选择小鼠Bpi基因第2、3外显子作为条件性敲除的目的片段,并在其两侧插入LoxP位点;运用LA-PCR技术,以129品系小鼠ES细胞基因组DNA为模板分步扩增包括Bpi第2、3外显子(中间同源臂)和上游同源臂在内的3.1 kb基因片段以及下游同源臂4.9 kb基因片段;构建pBSKⅡ-5SLoxP和ploxPFRTNeo-3L重组质粒,将前者酶切产物(3.1 kb)与酶切后的ploxPFRTNeo-3L质粒相连获得Bpi条件基因打靶载体。结果经多个限制性内切酶酶切鉴定和测序证实,构建的pBSKⅡ-5SLoxP、ploxPFRTNeo-3L重组质粒和Bpi条件基因打靶载体结构正确,与设计相符。结论成功构建了小鼠Bpi条件基因打靶载体。     

表达FLP重组酶pCEP4-FLP载体的构建及其在FLP/FRT重组系统中的应用

构建重组载体pCEP4-FLP和pEF1a-FRT-stop-FRT-GFP,重组载体pEF1a-FRT-stop-FRT-GFP瞬时转染PK-15细胞24h后,再将重组载体pCEP4-FLP瞬时转染该细胞,利用荧光显微镜观察PK-15细胞GFP蛋白的表达情况,利用细胞流式技术统计绿色荧光蛋白表达效率.结果表明:重组载体pCEP4-FLP在细胞内能够表达FLP重组酶,并且表达的FLP重组酶能够识别FRT位点,删除两同向FRT位点间的DNA片段,为FLP/FRT位点特异性重组系统在转基因猪的应用奠定了基础.     

A hypersensitive site in hsp70 chromatin requires adjacent not internal DNA sequence

Nuclease-hypersensitive sites in chromatin exist at the 5' side of many eukaryotic genes. To gain some understanding of the molecular basis of these hypersensitive sites, we have now examined the pair of sites upstream of the Drosophila hsp70 gene in a series of plasmids that contain deletions in the hypersensitive region and have been transformed into yeast cells. Hypersensitive sites 5' to a Drosophila hsp70 gene are preserved when this gene is introduced into yeast by transformation. We find that a yeast strain containing a plasmid in which the deletion extends through the first hypersensitive site still displays the normal pair of hypersensitive sites, so DNA sequences over which the first hypersensitive site is centred are not required for hypersensitivity at this position and the site can form over a foreign DNA sequence juxtaposed against this deletion end point. Deletions progressing further into the region bracketed by the pair of 5' hypersensitive sites eliminate the first hypersensitive site and alter the downstream site. We propose that the hypersensitive sites are generated through the binding of a protein that renders flanking sequences more accessible to nucleases, perhaps by preventing normal chromatin packaging.     

单子叶植物的FLP/frt位点特异性重组系统的构建

来自于啤酒酵母2?μm质粒的FLP/frt位点特异性重组系统可用于转基因植物（细胞）筛选完成后去除选择标记基因.水稻肌动蛋白actin基因启动子和玉米泛素ubiquitin基因启动子可有效驱动单子叶植物中外源基因的转录.为培育去除选择标记基因的抗盐耐旱单子叶转基因植物，构建了适合于单子叶植物的FLP/frt位点特异性重组系统. 该系统由含有FLP重组酶基因的植物表达载体pCAMBIA3300 Ubi FLP bar和含有frt位点的植物双抗（抗除草剂、抗盐耐旱）表达载体pCAMBIA1300 Ubi TsPPase frt als frtm以及pCAMBIA1300 Actin1 AtNHX1 frt als frtm组成.     

Filamentous phage integration requires the host recombinases XerC and XerD

Many bacteriophages and animal viruses integrate their genomes into the chromosomal DNA of their hosts as a method of promoting vertical transmission. Phages that integrate in a site-specific fashion encode an integrase enzyme that catalyses recombination between the phage and host genomes. CTX phi is a filamentous bacteriophage that contains the genes encoding cholera toxin, the principal virulence factor of the diarrhoea-causing Gram-negative bacterium Vibrio cholerae. CTX phi integrates into the V. cholerae genome in a site-specific manner; however, the approximately 6.9-kilobase (kb) CTX phi genome does not encode any protein with significant homology to known recombinases. Here we report that XerC and XerD, two chromosome-encoded recombinases that ordinarily function to resolve chromosome dimers at the dif recombination site, are essential for CTX phi integration into the V. cholerae genome. The CTX phi integration site was found to overlap with the dif site of the larger of the two V. cholerae chromosomes. Examination of sequences of the integration sites of other filamentous phages indicates that the XerCD recombinases also mediate the integration of these phage genomes at dif-like sites in various bacterial species.     

Expression of the intact C<Subscript>4</Subscript> type<Emphasis Type="Italic">pepc</Emphasis> gene cloned from maize in transgenic winter wheat

Maize intact C4-pepc gene was amplified through LA-PCR and successfully sub-cloned into modified vector pGreen0029 to form a stable expression construct named as pBAC214 (12 kb), which contains CaMV 35S promoter driven bar gene as selection marker. Comparing the cloned DNA sequences (6.7 kb) with published maize C4-pepc gene (GenBank accession E17154) sequences, the identity of DNA sequence alignment is 98.96%. There are only 49 differences between these two intact DNA sequences, of which 13 occur in the region of promoter, 18 in introns, and 18 in exons. The homology of mRNA sequence alignment is 99.38%, and the putative amino acids sequence identity is 99.38%. There are only 15 differences between these two mRNA, and these differences bring 4 sites mutant on the putative amino acids of PEPC protein. Through biolistic bombardment of PDS1000/He system, expression vector pBAC214 has been transformed into winter wheat. Southern blotting results show that the intact C4-pepc gene has been integrated into genome of winter wheat. SDS-PAGE analysis of leaf soluble protein in transgenic wheat showed that the intact C4opepc gene was well transcribed, spliced and translated as in maize. The enzyme activity of leaf PEPC in transgenic wheat has been detected. The activities of leaf PEPC increased over 3-5 times in some transgenic plants. The data of photosynthesis rate and transpiration rate of transgenic wheat flag leaves showed that the C4-pepc gene can increase the photosynthesis rate and transpiration rate of transgenic wheat.