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Effects of phosphate on the adsorption of glyphosate on three different types of Chinese soils 被引量:4
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作者 WANG Yu-jun ZHOU Dong-mei SUN Rui-juan 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2005年第5期711-715,共5页
Glyphosate (GPS) is a non-selective, post-mergence herbicide that is widely used throughout the world. Due to the similar molecular structures of glyphosate and phosphate, adsorption of glyphosate on soil is easily ... Glyphosate (GPS) is a non-selective, post-mergence herbicide that is widely used throughout the world. Due to the similar molecular structures of glyphosate and phosphate, adsorption of glyphosate on soil is easily affected by coexisting phosphate, especially when phosphate is applied at a significant rate in farmland. This paper studied the effects of phosphate on the adsorption of glyphosate on three different types of Chinese soils including two variable charge soils and one permanent charge soil. The results indicated that Freundlich equations used to simulate glyphosate adsorption isotherms gave high correlation coefficients(0.990-0.998) with K values of 2751, 2451 and 166 for the zhuanhong soil(ZH soil, Laterite), red soil( RS, Udic Ferrisol) and Wushan paddy soil(WS soil, Anthrosol), respectively. The more the soil iron and aluminum oxides and clay contained, the more glyphosate adsorbed. The presence of phosphate significantly decreased the adsorption of glyphosate to the soils by competing with glyphosate for adsorption sites of soils. Meanwhile, the effects of phosphate on adsorption of glyphosate on the two variable charge soils were more significant than that on the permanent charge soil. When phosphate and glyphosate were added in the soils in different orders, the adsorption quantities of glyphosate on the soils were different, which followed GPS-soil 〉 GPS-P-soil = GPS-Soil-P 〉 P-soil-GPS, meaning a complex interaction occurred among glyphosate, phosphate and the soils. 展开更多
关键词 SOIL GLYPHOSATE PHOSPHATE competitive adsorption
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A new species,Gerres septemfasciatus(Perciformes:Gerreidae) from the Chinese coastal waters of the South China Sea
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作者 刘静 颜云榕 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2009年第3期555-557,共3页
We describe a new species of gerreid fish,Gerres septemfasciatus,based on four specimens collected from the northern South China Sea.G.septemfasciatus most closely resembles G.limbatus in general appearance.However,G.... We describe a new species of gerreid fish,Gerres septemfasciatus,based on four specimens collected from the northern South China Sea.G.septemfasciatus most closely resembles G.limbatus in general appearance.However,G.septemfasciatus is distinguished from the latter and other congeners by having 3 to 3.5 scales between the base of the fifth dorsal spine and lateral line.This species has a distinctive color pattern,including 7-8 regular,vertical,blue-grayish bands on its side.The distribution of this species is currently known to include the Chinese coastal waters of the South China Sea,but may be also include the coastal waters of southeastern Asia. 展开更多
关键词 TAXONOMY Gerreidae new species Gerres septemfasciatus sp. nov. the South China Sea
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Purification and Identification of a Clotting Protein from the Hemolymph of Chinese Shrimp (Fenneropenaeus chinensis)
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作者 WANG Baojie PENG Hongni +3 位作者 LIU Mei JIANG Keyong ZHANG Guofan WANG Lei 《Journal of Ocean University of China》 SCIE CAS 2013年第3期477-483,共7页
The clotting protein(CP) plays important and diverse roles in crustaceans,such as coagulation and lipid transportation.A clotting protein was purified from the hemolymph of Chinese shrimp Fenneropenaeus chinensis(name... The clotting protein(CP) plays important and diverse roles in crustaceans,such as coagulation and lipid transportation.A clotting protein was purified from the hemolymph of Chinese shrimp Fenneropenaeus chinensis(named as Fc-CP) with Q sepharose HP anion-exchange chromatography and phenyl sepharose HP hydrophobic interaction chromatography.Fc-CP was able to form stable clots in vitro in the presence of hemocyte lysate and Ca2+,suggesting that the clotting reaction is catalyzed by a Ca2+-dependent transglutaminase in shrimp hemocytes.The molecular mass of Fc-CP was 380 kDa under non-reducing conditions and 190 kDa under reducing conditions as was determined with SDS-PAGE.CP exists as disulfide-linked homodimers and oligomers.The N-terminal amino acid sequence of Fc-CP was identical to that of shrimps including Penaeus monodon,Farfantepenaeus paulensis and Litopenaeus vannamei;and similar to that of other decapods.The purified Fc-CP was digested with trypsin and verified on an ABI 4700 matrix-assisted laser desorption/ionization tandem time-of-flight(MALDI-TOF/TOF) mass spectrometry.Our results will aid to better understanding the coagulation mechanism of shrimp hemolymph. 展开更多
关键词 Fenneropeaaeus chinensis clotting protein purification proteomic identification MALDI-TOF/TOF MS
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A snapshot of the Chinese SOL Project
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作者 Changbao Li Jiuhai Zhao +17 位作者 Hongling Jiang Yu Geng Yuanyuan Dai Huajie Fan Dongfen Zhang Jinfeng Chen Fei Lu Jinfeng Shi Shouhong Sun Jianjun Chen Xiaohua Yang Chen Lu Mingsheng Chen Zhukuan Cheng Hongqing Ling Ying Wang Yongbiao Xue Chuanyou Li 《Journal of Genetics and Genomics》 SCIE CAS CSCD 北大核心 2008年第7期387-390,共4页
In 2003, the International Solanaceae Project (SOL) was initiated by an international consortium of ten countries including Korea, China, the United Kingdom, India, the Netherlands, France, Japan, Spain, Italy and t... In 2003, the International Solanaceae Project (SOL) was initiated by an international consortium of ten countries including Korea, China, the United Kingdom, India, the Netherlands, France, Japan, Spain, Italy and the United States. The first major effort of the SOL aimed to produce a DNA sequence map for euchromatin regions of 12 chromosomes of tomato (Solanum lycopersicum) before 2010. Here we present an update on Chinese effort for sequencing the euchromatin region of chromosome 3. 展开更多
关键词 TOMATO Solanum lycopersicum SOLANACEAE SOL
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Genetic difference of Chinese horseshoe crab(Tachypleus tridentatus) in southeast coast of China based on mitochondrial COI gene analysis
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作者 WENG Zhaohong XIAO Zhiqun +2 位作者 XIE Yangjie WANG Zhiyong GUI Jianfang 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2012年第3期132-137,共6页
Population genetic structure and historical demography of Chinese horseshoe crab (T.tridentatus)along southeast coast of China were inferred from the sequence data of mitochondrial cytochrome c oxidase subunit Ⅰ (COI... Population genetic structure and historical demography of Chinese horseshoe crab (T.tridentatus)along southeast coast of China were inferred from the sequence data of mitochondrial cytochrome c oxidase subunit Ⅰ (COI) fragment.The sequence analysis for 964 bp COI fragment was conducted in 28 individuals collected from five localities:Ninghai in Zhejiang Province,Meizhou and Zhangpu in Fujian Province,Beihai of Guangxi Zhuang Autonomous Region and Danzhou of Hainan Province.Sequence variation was relatively low with a total of seven transitions observed.In all localities,Haplotype H3 was the dominant type observed among eight haplotypes defined previously,and was at the center of radiation in Median-Joining network.The prolonged star-like network suggests a signature of population expansions.The level of diversity was low in total,with haplotype diversity ( Hd) being equal to 0.765 and nucleotide diversity (π) being equal to 0.00118,respectively.The genetic structure analysis revealed the significant genetic difference between Ninghai and Danzhou populations.Both mismatch distribution analysis and Fu's Fs test provided consistent inference of historic population expansion.The low genetic diversity of horseshoe crab observed along China coast indicated that urgent measures should be taken to protect this rare marine animal. 展开更多
关键词 Tachypleus tridentatus genetic difference cytochrome c oxidase subunit I gene MTDNA
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Summation and decomposition of principal stresses in the crust 被引量:4
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作者 石耀霖 《地震学报》 CSCD 北大核心 2004年第1期106-109,共4页
关键词 地应力 方位角 张量 震源机制 水压破裂法
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Gene expression and metabolite profiles of cotton fiber during cell elongation and secondary cell wall synthesis 被引量:53
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作者 Jin-Ying Gou Ling-Jian Wang +2 位作者 Shuang-Ping Chen Wen-Li Hu Xiao-Ya Chen 《Cell Research》 SCIE CAS CSCD 2007年第5期422-434,共13页
Cotton fibers elongate rapidly after initiation of elongation, eventually leading to the deposit of a large amount of cellulose. To reveal features of cotton fiber cells at the fast elongation and the secondary cell w... Cotton fibers elongate rapidly after initiation of elongation, eventually leading to the deposit of a large amount of cellulose. To reveal features of cotton fiber cells at the fast elongation and the secondary cell wall synthesis stages, we compared the respective transcriptomes and metabolite profiles. Comparative analysis of transcriptomes by cDNA array identified 633 genes that were differentially regulated during fiber development. Principal component analysis (PCA) using expressed genes as variables divided fiber samples into four groups, which are diagnostic of developmental stages. Similar grouping results are also found if we use non-polar or polar metabolites as variables for PCA of developing fibers. Auxin signaling, wall-loosening and lipid metabolism are highly active during fiber elongation, whereas cellulose biosynthesis is predominant and many other metabolic pathways are downregulated at the secondary cell wall synthesis stage. Transcript and metabolite profiles and enzyme activities are consistent in demonstrating a specialization process of cotton fiber development toward cellulose synthesis. These data demonstrate that cotton fiber cell at a certain stage has its own unique feature, and developmental stages of cotton fiber cells can be distinguished by their transcript and metabolite profiles. During the secondary cell wall synthesis stage, metabolic pathways are streamed into cellulose synthesis. 展开更多
关键词 cotton fiber TRANSCRIPTOME metabolite profile AUXIN cell elongation cellulose synthesis
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GIS-Based Assessment of Land Suitability for Optimal Allocation in the Qinling Mountains, China 被引量:35
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作者 LIU Yan-Sui WANG Jie-Yong GUO Li-Ying 《Pedosphere》 SCIE CAS CSCD 2006年第5期579-586,共8页
A GIS-based method was used to assess land suitability in the Qinling Mountains, Shaanxi Province of China through simultaneous consideration of physical features and current land use. Through interpretation of Landsa... A GIS-based method was used to assess land suitability in the Qinling Mountains, Shaanxi Province of China through simultaneous consideration of physical features and current land use. Through interpretation of Landsat TM images and extensive field visits the area was modeled into 40 land types in five altitudinal zones (valleys and gullies, hillsides and terraces, foothills, mid-mountain, and sub-alpine mountain). Then, a suitability score was assigned to five physical factors (climate, hydrology, topography, soil, and vegetation). Next, their integrated overall suitability value scores were compared with the observed land cover to determine whether it should be reallocated a new use. Results showed that the five suitability classes of agriculture, forest, grassland, farmland-woodland, and scrub-pasture had altitudinal stratification and a total of 1151 km2 (8.89%) of lands on the northern slopes of the Qinling Mountains had to be reallocated. To achieve this reallocation, 657 km2 of arable land should be reduced, and forest, grassland and scrub-pasture increased by 615 km2, 131 km2 and 405 km2, respectively. Implementation of these recommended land reallocations should help achieve suitable use of land resources and prevent land degradation. 展开更多
关键词 GIS LANDFORMS optimal allocation Qinling Mountains suitability evaluation
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Enhanced biological nutrient removal by the alliance of a heterotrophic nitrifying strain with a nitrogen removing ecosystem 被引量:17
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作者 Naeem ud din Ahmad XU Haiying +2 位作者 CHEN Liping LIU Zhipei LIU Shuangjiang 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2008年第2期216-223,共8页
Nitrogen removal from synthetic wastewater was investigated in an airlift bioreactor (ALB), augmented with a novel heterotrophic nitrifier Pseudonocardia ammonioxydans H9^T under organic carbon to nitrogen ratios (... Nitrogen removal from synthetic wastewater was investigated in an airlift bioreactor (ALB), augmented with a novel heterotrophic nitrifier Pseudonocardia ammonioxydans H9^T under organic carbon to nitrogen ratios (Corg/N) ranging from 0 to 12. Effect of the inoculated strain was also determined on the settling properties and the removal of chemical oxygen demand (COD). Two laboratory scale reactors were set up to achieve a stable nitrifying state under the same physicochemical conditions of hydraulic retention time (HRT), temperature, pH and dissolved oxygen (DO), and operated under the sequencing batch mode. The level of DO was kept at 0.5- 1.5 mg/L by periodic stirring and aeration. Each specific Corg/N ratio was continued for duration of 3 weeks. One of the reactors (BR2) was inoculated with P ammonioxydans H9^T periodically at the start of each Corg/N ratio. Sludge volumetric index (SVI) improved with the increasing Corg/N ratio, but no significant difference was detected between the two reactors. BR2 showed higher levels of nitrogen removal with the increasing heterotrophic conditions, and the ammonia removal reached to the level of 82%-88%, up to10% higher than that in the control reactor (BR1) at Corg/N ratios higher than 6; however, the ammonia removal level in experimental reactor was up to 8% lower than that in control reactor at Corg/N ratios lower than 2. The COD removal efficiency progressively increased with the increasing Corg/N ratios in both of the reactors. The COD removal percentage up to peak values of 88%-94% in BR2, up to 11% higher than that in BR1 at Corg/N ratio higher than 4. The peak values of ammonia and COD removal almost coincided with the highest number (18%-27% to total bacterial number) of the exogenous bacterium in the BR2, detected as colony forming units (CFU). Furthermore, the removal of ammonia and COD in BR2 was closely related to the number of the inoculated strain with a coefficient index (R2) up to 0.82 and 0.85 for ammonia and COD, respectively. These results suggest that it was more efficient for both the ammonia and carbon nutrient removals in a reactor inoculated with a heterotrophic nitrifier at high Corg/N ratio, inferring that the heterotrophic nitrifers would be practically more available in the treatment of wastewater with high level of ammonia and COD. 展开更多
关键词 air-lift bioreactor (ALB) bioaugrnentation Corg/N ratio COD and ammonia removal sequencing batch mode heterotrophic nitrifier Pseudonocardia ammonioxydans H9^T
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LA-ICP-MS Zircon U-Pb Geochronology and Petrology of the Muchang Alkali Granite,Zhenkang County,Western Yunnan Province,China 被引量:21
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作者 YE Lin GAO Wei +2 位作者 CHENG Zengtao YANG Yulong TAO Yan 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2010年第6期1488-1499,共12页
The Muchang composite intrusion is located about 14 km southeast of the Fengwei town and south of the Baoshan-Zhenkang block.The rift-related intrusion consists of the early-stage riebeckite nordmarkite in the east an... The Muchang composite intrusion is located about 14 km southeast of the Fengwei town and south of the Baoshan-Zhenkang block.The rift-related intrusion consists of the early-stage riebeckite nordmarkite in the east and west sides and the discontinuous marginal zone,the late-stage main body of dominant riebeckite granite,and minor aegirine granite.Studies on petrological geochemistry and LA-ICP-MS zircon U-Pb dating of the late-stage riebeckite granite,origin and evolution of the Muchang alkali granite and the relationship between the granite and the associated skarn-type Luziyuan Pb-Zn deposit are discussed in this paper.The results show that the Muchang alkali granites belong to A-type granites,which are characterized by enrichment in Al_2O_3,SiO_2,total alkali and Fe, depletion in MgO and CaO contents with high FeO_T/MgO ratios.The REE concentrations are relatively high,exhibiting highly fractionated LREE patterns with significantly Eu negative anomaly. The Muchang granites are obviously enriched in lithophile elements(e.g.,Rb,K,U and Th) and high field strength elements(e.g.,Zr,Hf,Nb,Y and Ga) with high 10000×Ga/Al ratios and depleted in Sr, Ba,Ti,Cr and Ni,which are similar to those of the A-type granites and quite different from those of S-type andⅠ-type granites.The LA-ICP-MS zircon dating results of the Muchang granite gave a weighted mean age of 266.2±5.4 Ma(2σ),suggesting that they were formed in the stage of extension at the end of post-collision at Middle Permian and the consumption of Paleo-Tethys ocean took place before 266 Ma. It is suggested that the unexposed intermediate-acid intrusive rocks in the Luziyuan ore district,which is the "sister" rocks material of the Muchang granites and related closely to Luziyuan Pb-Zn mineralization,were the product of Middle Permian. 展开更多
关键词 A-type granite U-Pb age Muchang alkali granite tectonic setting evolution of Tethys in southern Sanjiang area
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Prediction of Debris-flow Danger Area by Combining Hydrological and Inundation Simulation Methods 被引量:32
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作者 CUI Peng 《Journal of Mountain Science》 SCIE CSCD 2011年第1期1-9,共9页
Debris flows have caused serious human casualties and economic losses in the regions strongly affected by the Ms8.0 Wenchuan earthquake of 2oo8. Debris flow mitigation and risk assessment is a key issue for reconstruc... Debris flows have caused serious human casualties and economic losses in the regions strongly affected by the Ms8.0 Wenchuan earthquake of 2oo8. Debris flow mitigation and risk assessment is a key issue for reconstruction. The existing methods of inundation simulation are based on historical disasters and have no power of prediction. The rain- flood method can not yield detailed flow hydrograph and does not meet the need of inundation simulation. In this paper, the process of water flow was studied by using the Arc-SCS model combined with hydraulic method, and then the debris flow runoff process was calculated using the empirical formula combining the result from Arc-SCS. The peak discharge and runoff duration served as input of inundation simulation. Then, the dangerous area is predicted using kinematic wave method and Manning equation. Taking the debris flow in Huashiban gully in Beichuan County, Sichuan Province, China on 24 Sep. 2oo8 as example, the peak discharge of water flow and debris flow were calculated as 35.52 m3·s-1 and 215.66 m3·s-, with error of 4.15% compared to the measured values. The simulated area of debris-flow deposition was 161,500 m2, vs. the measured area of 144,097 m2, in error of 81.75%. The simulated maximum depth was 12.3 m, consistent with the real maximum depth between lO and 15 m according to the field survey. The minor error is mainly due to the flow impact on buildings and variations in cross-section configuration. The present methodology can be applied to predict debrisflow magnitude and evaluate its risk in other watersheds inthe earthquake area. 展开更多
关键词 Debris flow Arc-SCS model Inundation simulation Risk analysis Wenchuan earthquake
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Effects of sediment dredging on water quality and zooplankton community structure in a shallow of eutrophic lake 被引量:42
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作者 Shiyang Zhang Qiaohong Zhou +3 位作者 Dong Xu Jidong Lin Shuiping Cheng Zhenbin Wu 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2010年第2期218-224,共7页
Effects of suction dredging on water quality and zooplankton community structure in a shallow of eutrophic lake, were evaluated. The results showed that a decreasing trend for levels of phosphorus, organic matter, tot... Effects of suction dredging on water quality and zooplankton community structure in a shallow of eutrophic lake, were evaluated. The results showed that a decreasing trend for levels of phosphorus, organic matter, total suspended solids, Chlorophyll a and Secchi transparency in the water column was found, while levels of water depth, electrical conductivity, total dissolved solids and NO3^--N concentration increased markedly post-dredging. The effects of dredging on dissolved oxygen, pH value and temperature were almost negligible. The zooplankton community structure responded rapidly to the environmental changes caused mainly by dredging. As a result, the abundance of rotifers decreased, while the density of zooplanktonic crustaceans increased markedly. The representative taxa were Brachionus angularis, B. budapestinensis, B. diversicornis, Synchaeta spp. and Neodiaptomus schmackeri. A distinct relationship between zooplankton taxa composition and their environment, unraveled by a redundancy analysis, indicating that the measured environment contributed to the variations in the zooplankton community structure to some extent. The first four synthetic environmental variables explained 51.7% of the taxonomic structure. Therefore, with the reduction of internal nutrient load and a shift in dominance by less eutrophic species, it inferred that dredging might be one of effective measures for environmental improvements of such lakes. 展开更多
关键词 zooplankton community structure redundancy analysis internal nutrient load
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Seasonal variation of Microcystis in Lake Taihu and its relationships with environmental factors 被引量:16
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作者 TAN Xiao KONG Fanxiang +3 位作者 ZENG Qingfei CAO Huansheng QIAN Shanqin ZHANG Min 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2009年第7期892-899,共8页
In order to monitor the changes of Microcystis along with temporal and spatial variations, seasonal variation of Microcystis in Lake Taihu was investigated by 16S-23S rRNA internal transcribed spacer denaturing gradie... In order to monitor the changes of Microcystis along with temporal and spatial variations, seasonal variation of Microcystis in Lake Taihu was investigated by 16S-23S rRNA internal transcribed spacer denaturing gradient gel electrophoresis (16S-23S rRNA-ITS DGGE) and microscopic evaluation. Samples were collected quarterly at four sites (River Mouth, Meiliang Bay, Cross Area, and Lake Center) from August 2006 to April 2007. Results showed that Microcystis dominated total phytoplankton abundance at the four sites in all seasons except winter. The average annual abundance of Microcystis was relatively high at River Mouth and Meiliang Bay, reaching 81.22×10^6 and 61.32×10^6 cells/L, respectively. For temporal variations, Shannon-Wiener diversity index (H') according to DGGE profile revealed the richness of Microcystis in summer (H' = 1.375±0.034) and winter (H' = 1.650 ±0.032) was lower than that in spring (H' = 2.078 ±0.031) and autumn (H' = 2.365 ±0.032) (P 〈 0.05). While for spatial variations, the richness of Microcystis at River Mouth (H' = 2.015± 0.074) was higher than at other sites during four seasons (P 〈 0.01). Very few differences of Microcystis diversity in the same season were observed among the other three sites (P 〉 0.05). Canonical correspondence analysis (CCA) was performed to elucidate the relationships between Microcystis operational taxonomic units (OTUs) composition and the environmental factors. Results of CCA revealed that temperature was strongly positively correlated with the first axis (r = 0.963), while TSS was negative correlated with the second axis (r = -0.716). Phylogenetic tree based on the sequencing results of target bands on DGGE gel indicated that samples collected in summer and winter constituted two separated clusters. 展开更多
关键词 Lake Taihu BLOOMS MICROCYSTIS rRNA-ITS DGGE canonical correspondence analysis
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Comparison of growth and survival of larvae among different shell color stocks of bay scallop Argopecten irradians irradians(Lamarck 1819) 被引量:26
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作者 郑怀平 张国范 刘晓 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2005年第2期183-188,共6页
In order to improve production and breed new broods of bay scallop Argopecten irradians irradians, different-colored orange, purple and white lines were established by two mating methods of self-fertilization and mass... In order to improve production and breed new broods of bay scallop Argopecten irradians irradians, different-colored orange, purple and white lines were established by two mating methods of self-fertilization and mass spawning at a commercial scallop hatchery in spring, 2002. And then larval growth and survival of different lines was compared to test whether there is a relationship between shell color and growth and survival at early developmental stage. Both growth and survival have no significant differences among different experimental larvae of self-fertilization or mass spawning. Results are as following in the order of orange, purple and white shell stock. For the self-fertilization, growth rates of larvae were 6.174, 6.412, and 6.599 μm/d, respectively. Survival rates of larvae at Day 3 were 74.41%, 76.86%, and 82.05%; Day 6 were 49.14%, 65.63%, and 52.79%; and Day 9 were 25.06%, 20.80%, and 26.47%, respectively. For the mass spawning, the growth rates were 7.836, 7.941, and 7.878 μm/d, respectively. Survival rates at Day 3 were 93.05%, 91.95%, and 92.50%; Day 6 were 79.17%, 78.05%, and 82.50%; and Day 9 were 34.72%, 36.67%, and 38.33%, respectively. The absence of any relationship between shell color and growth and survival at the larval stage may be resulted from their common genetic basis. 展开更多
关键词 Argopecten irradians irradians shell color larvae growth and survival self-fertilization and mass spawning
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Single and joint stress of acetochlor and Pb on three agricultural crops in northeast China 被引量:14
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作者 CHAO Lei ZHOU Qi-xing +2 位作者 CHEN SU CUI Shuang WANG Mei-e 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2007年第6期719-724,共6页
In order to evaluate ecological risk of agrochemicals in agricultural environment, single and joint toxic effects of an important herbicide and a typical heavy metal on root elongation of crops were investigated. Seed... In order to evaluate ecological risk of agrochemicals in agricultural environment, single and joint toxic effects of an important herbicide and a typical heavy metal on root elongation of crops were investigated. Seeds of the three crops including wheat (Triticum aestivum), Chinese cabbage (Brassica pekimensis) and soybean (Glycine max) as the main crops in northeast China were exposed to acetochior as a herbicide and lead (Pb) as a heavy metal using the pot-culture method, and meadow brown soil as one of the main soils distributed in northeast China was applied in the investigation. The results indicated that the interactive effects of the two pollutants on root elongation of the three crops were very complicated although they had markedly significant (P〈0.01) linear interrelationships based on the regression analyses. When the concentration of added Pb^2+ reached 200 mg/kg, acetochlor and Pb had an antagonistic effect on the inhibition of root elongation of the three crops. However, acetochlor and Pb had significantly (P〈0.05) synergic effects on the inhibition of root elongation when concentration of added Pb^2+ was up to 1000 mg/kg. At the low concentration of added Pb, joint toxicity of acetochlor and Pb was more dependent on the concentration of Pb. Among the three crops, wheat was the most sensitive to the toxicity of Pb and Chinese cabbage was the most sensitive to the toxicity of acetochlor. 展开更多
关键词 ACETOCHLOR PB ECOTOXICOLOGY joint effect Chinese cabbage (Brassica pekimensis) soybean (Glycine max) wheat (Triticum aestivum)
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Antibacterial Mechanism of Copper-bearing Antibacterial Stainless Steel against E.Coli 被引量:25
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作者 Li NAN Weichao YANG +4 位作者 Yongqian LIU Hui XU Ying LI Manqi LU Ke YANG 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2008年第2期197-201,共5页
A preliminary study was made on the antibacterial mechanism of copper-bearing antibacterial stainless steels against E.coli through experiments of microbiology such as EDTA (ethylenediaminetetraacetic acid) complexi... A preliminary study was made on the antibacterial mechanism of copper-bearing antibacterial stainless steels against E.coli through experiments of microbiology such as EDTA (ethylenediaminetetraacetic acid) complexing, DNA smearing and AFM (atomic force microscope) observation. It was measured that the antibacterial stainless steels showed excellent antibacterial functions with antibacterial rate to E.coli over 99.99%. The antibacterial rate was weak if the bacteria solution was complexed by EDTA, indicating that the copper ions play a dominant role in the antibacterial effect of the antibacterial stainless steels. The electrophoresis experiment did not show the phenomenon of DNA smearing for E.coli after contacting antibacterial stainless steels, which meant that DNA of E.coli was not obviously damaged. It was observed by AFM that the morphology of E.coli changed a lot after contacting antibacterial stainless steels, such as cell walls being seriously changed and lots of contents in the cells being leaked. 展开更多
关键词 COPPER Stainless steel E.COLI Antibacterial mechanism
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Degradation of Populus euphratica community in the lower reaches of the Tarim River, Xinjiang, China 被引量:14
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作者 LIU Jia-zhen CHEN Ya-ning +2 位作者 CHEN Yong-jin ZHANG Na LI Wei-hong 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2005年第5期740-747,共8页
To investigate the relationships between the degradation of plant community and groundwater level in the lower reaches of the Tarim River, nine monitored sections were set along the main stream, where there had been n... To investigate the relationships between the degradation of plant community and groundwater level in the lower reaches of the Tarim River, nine monitored sections were set along the main stream, where there had been no runoff for nearly 30 years. The characteristics of plant communities were analyzed. It was found that the coverage of trees gradually decreased along the groundwater depth gradient, while the coverage of shrubs slightly increased rather than decreased at first and then gradually decreased, and the coverage of herbs steadily decreased at the beginning and then quickly decreased. The species diversity and species richness of both herbs and woody plants showed obvious degrading trends, while the variations in species evenness were slight. The degrading sequences of species were related to their physiological and ecological characteristics, especially their sensitivity to changes of groundwater table. The herbs with shallow roots first degenerated or disappeared when the groundwater table fell, and then did the deep-rooted herbs, and finally the trees and shrubs with strong tolerance to drought degenerated. The Populus euphratica communities showed typical degrading characteristics, namely the dominant species Populus euphratica remained its dominant status during the degradation. Overall, the existence of strongly tolerant-drought species was the obvious indication of plant species degradation; while simplification of community structure and the decrease of species richness were the obvious indication of plant community degradation. 展开更多
关键词 DEGRADATION plant community COVERAGE species diversity Tarim River
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MyD88-independent activation of a novel actin-Cdc42/Rac pathway is required for Toll-like receptor-stimulated phagocytosis 被引量:13
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作者 Ling Kong Bao-Xue Ge 《Cell Research》 SCIE CAS CSCD 2008年第7期745-755,共11页
Phagocytosis and subsequent degradation of pathogens by macrophages play a pivotal role in host innate immune responses to microbial infection. Recent studies have shown that Toll-like receptors (TLRs) play an impor... Phagocytosis and subsequent degradation of pathogens by macrophages play a pivotal role in host innate immune responses to microbial infection. Recent studies have shown that Toll-like receptors (TLRs) play an important role in promoting the clearance of bacteria by up-regulating the phagocytic activity of macrophages. However, information regarding the signaling mechanism of TLR-mediated phagocytosis is still limited. Here, we provide evidence that the stimulation of TLR4 with LPS leads to activation of multiple signaling pathways including MAP kinases, phosphatidylinositide 3-kinase (PI3K), and small GTPases in the murine macrophage-like cell line RAW264.7. Specific inhibition of Cdc42/Rac or p38 MAP kinase, but not PI3K, reduced TLR4-induced phagocytosis of bacteria. Moreover, we have found that either inhibition of actin polymerization by cytochalasin D or the knockdown of actin by RNAi markedly reduced the activation of Cdc42 and Rac by LPS. TLR4-induced activation of Cdc42 and Rac appears to be independent of MyD88. Taken together, our results described a novel actin-Cdc42/Rac pathway through which TLRs can specifically provoke phagocytosis. 展开更多
关键词 innate immunity Toll-like receptors PHAGOCYTOSIS GTPASES ACTIN P38
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Geochemical and isotopic characteristics of volcanic rocks from the northern East China Sea shelf margin and the Okinawa Trough 被引量:19
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作者 ZENG Zhigang YU Shaoxiong +5 位作者 WANG Xiaoyuan FU Yongtao YIN Xuebo ZHANG Guoliang WANG Xiaomei CHEN Shuai 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2010年第4期48-61,共14页
Volcanic rocks both from the northern East China Sea (NECS) shelf margin and the northern Okinawa Trough are subalkaline less aluminous,and lower in High Field Strength Elements (HFSE).These rocks are higher in La... Volcanic rocks both from the northern East China Sea (NECS) shelf margin and the northern Okinawa Trough are subalkaline less aluminous,and lower in High Field Strength Elements (HFSE).These rocks are higher in Large Ion Lithophile Elements (LILE),thorium and uranium contents,positive lead anomalies,negative Nb-Ta anomalies,and enrichment in Light Rare Earth Elements (LREE).Basalts from the NECS shelf margin are akin to Indian Ocean Mid-Ocean Ridge Basalt (MORB),and rhyolites from the northern Okinawa Trough have the highest 207 Pb/ 204 Pb and 208 Pb/ 204 Pb ratios.The NECS shelf margin basalts have lower 87 Sr/ 86 Sr ratios,ε N d and σ 18 O than the northern Okinawa Trough silicic rocks.According to 40 K– 40 Ar isotopic ages of basalts from the NECS shelf margin,rifting of the Okinawa Trough may have been active since at least 3.65–3.86 Ma.The origin of the NECS shelf margin basalt can be explained by the interaction of melt derived from Indian Ocean MORB-like mantle with enriched subcontinental lithosphere.The basalts from both sides of the Okinawa Trough may have a similar origin during the initial rifting of the Okinawa Trough,and the formation of basaltic magmas closely relates to the thinning of continental crust.The source of the formation of the northern Okinawa Trough silicic rocks was different from that of the middle Okinawa Trough,which could have been generated by the interaction of basaltic melt with an enriched crustal component.From the Ryukyu island arc to East China,the Cenozoic basalts have apparently increasing trends of MgO contents and ratios of LREE to Heavy Rare Earth Elements (HREE),suggesting that the trace element variabilities of basalts may have been influenced by the subduction of the Philippine Sea plate,and that the effects of subduction of the Philippine Sea plate on the chemical composition of basaltic melts have had a decreasing effect from the Ryukyu island arc to East China. 展开更多
关键词 volcanic rocks geochemical characteristics northern East China Sea shelf margin Okinawa Trough
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Successful generation of cloned mice using nuclear transfer from induced pluripotent stem cells 被引量:10
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作者 Shuya Zhou Chenhui Ding +10 位作者 Xiaoyang Zhao Eryao Wang Xiangpeng Dai Lei Liu Wei Li Zichuan Liu Haifeng Wan Chunjing Feng Tang Hai Liu Wang Qi Zhou 《Cell Research》 SCIE CAS CSCD 2010年第7期850-853,共4页
Dear Editor, It is now well known that somatic cells can be efficiently reprogrammed into induced pluripotent stem cells (iPSCs) by forced expression of defined factors [1- 3]. These cells, like embryonic stem cel... Dear Editor, It is now well known that somatic cells can be efficiently reprogrammed into induced pluripotent stem cells (iPSCs) by forced expression of defined factors [1- 3]. These cells, like embryonic stem cells (ESCs), have true pluripotency as shown by the live, fertile mice that can be generated through the tetraploid complementation assay using these iPSCs [4, 5]. So far, iPSCs have been generated from many species including mice, primate, 展开更多
关键词 细胞核移植 多能干细胞 诱导 小鼠 克隆 胚胎干细胞 灵长类动物 ESCS
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