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Effects of free iron oxyhydrates and soil organic matter on copper sorption-desorption behavior by size fractions of aggregates from two paddy soils

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Journal of Environmental sciences 2009年第5期21卷 618-624页

作者： WANG Fang, PAN Genxing, LI Lianqing Institute of Resource, Ecosystem and Environment of agriculture, Nanjing Agricultural university, Nanjing 210095, china. [a]Institute of Resource Ecosystem and Environment of Agriculture Nanjing Agricultural University Nanjing 210095 China

Effects of free iron oxyhydrates （Fed） and soil organic matter （SOM） on copper （Cu^2＋） sorption-desorption behavior by size fractions of aggregates from two typical paddy soils （Ferric-Accumulic Stagnic Anthrosol （Soil H） and Gleyic Stagnic Anthrosol （Soil W）） were investigated with and without treatments of dithionite-citrate-bicarbonate and of H2O2. The size fractions of aggregates were obtained from the undisturbed bulk topsoil using a low energy ultrasonic dispersion procedure. Experiments of equilibrium sorption and subsequent desorption were conducted at soil water ratio of 1：20, 25℃. For Soil H, Cu^2＋ sorption capacity of the DCB-treated size fractions was decreased by 5.9% for fine sand fraction, by 40.4% for coarse sand fraction, in comparison to 2.9% for the bnlk sample. However, Cu^2＋ sorption capacities of the H2O2-treated fractions were decreased by over 80% for the coarse sand fraction and by 15% for the clay-sized fraction in comparison to 88% for bulk soil. For Soil W, Cu^2＋ sorption capacity of the DCB-treated size fraction was decreased by 30% for the coarse sand fraction and by over 75% for silt sand fraction in comparison to 44.5% for the bulk sample. Cu^2＋ sorption capacities of the H2O2-treated fractions were decreased by only 2.0% for the coarse sand fraction and by 15% for the fine sand fraction in comparison to by 3.4% for bulk soil. However, Cu^2＋ desorption rates were increased much in H2O2-treated samples by over 80% except the clay-sized fraction （only 9.5%） for Soil H. While removal of SOM with H2O2 tendend to increase the desorption rate, DCB- and H2O2-treatments caused decrease in Cu^2＋ retention capacity of size fractions, Particularly, there hardly remained Cu^2＋ retention capacity by size fractions from Soil H after H2O2 treatment except for clay-sized fraction. These findings supported again the dominance of the coarse sand fraction in sorption of metals and the preference of absorbed metals bound to SOM in differently stabilized

关键词： paddy soils Cn^2+ sorption-desorption soil organic matter free iron oxyhydrates size fraction of aggregates

Sequencing and analysis of the complete mitochondrial DNA of Russell's snapper (***)

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Progress in Natural science:Materials International 2008年第10期18卷 1233-1238页

作者： Yusong Guo~(a,1) Zhongduo Wang~(a,b,1) Chuwu Liu~(a,*) Yun Liu~b ~a Fisheries college,Guangdong Ocean university,Zhanjiang 524025,china.~b college of life science,Hunan Normal university,Changsha 410081,china Fisheries college Guangdong Ocean University Zhanjiang 524025 China college of life science Hunan Normal University Changsha 410081 China

The entire mitochondrial DNA sequence (mitogenome) of Russell’s snapper (Lutjanus russellii) was determined using long PCR and primer-walking methodology,representing the first complete mitogenome accessioned for Lutjanid fishes (16,505 bp,GenBank Acces- sion ***514208).The mitogenome was similar in gene composition and order to those of other vertebrates,having 37 structural genes,i.e.,two ribosomal RNAs,22 transfer RNAs,and 13 protein-coding *** analyses based on the mtDNA sequence of Russell’s snapper supported a close relationship between Lutjaninae and Caesioninae,consistent with taxonomic hypotheses based on *** studies utilizing mitogenomes are needed to resolve high-level relationships among snappers.

关键词： Lutjanus russellii Mitochondrial DNA Mitogenome Complete mtDNA sequence Long PCR

Density functional theory study on the structural and electronic properties of Ag-adsorbed (MgO)_n clusters

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science china.Physics,Mechanics & Astronomy) 2009年第5期52卷 734-741页

作者： GE GuiXian1, JING Qun1 & LUO YouHua2,3 1 Key Laboratory of Ecophysics and Department of Physics, Normal college, Shihezi university, Shihezi 832003, china.2 School of science, East china.university of science and Technology, Shanghai 200237, china.3 Institute for Theoretical Physics, Henan university, Kaifeng 475004, china Key Laboratory of Ecophysics and Department of Physics Normal College Shihezi University Shihezi 832003 China School of science East China University of Science and Technology Shanghai 200237 China Institute for Theoretical Physics Henan University Kaifeng 475004 China

Equilibrium geometries, charge distributions, stabilities and electronic properties of the Ag-adsorbed (MgO)n (n = 1-8) clusters have been investigated by density functional theory (DFT) with generalized gradient approximation (GGA) for exchange-correlation functional. The results show that hollow site is energetically preferred for n≥4, and the incoming Ag atoms tend to cluster on the existing Ag cluster. The Mulliken populations indicate that the interaction between the Ag atom and Magnesia clusters is mainly induced by a weak atomic polarization. The adsorbed Ag atom only causes charge redistributions of the atoms near itself. The effect of the adsorbed Ag atom on the bonding natures and structural features of Magnesia clusters is minor. Furthermore, the investigations on the first energy difference, fragmentation energies and electron affinities show that the Ag(MgO)4 and Ag(MgO)6 are the most stable among studied clusters.

关键词： Ag (MgO)_n clusters geometries electronic properties

New fossil ommatid (Coleoptera:Archostemata:Ommatidae) from Jehol Biota of western Liaoning, china

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Progress in Natural science:Materials International 2006年第6期16卷 639-643页

作者： REN Dong, TAN Jingjing and GE Siqin (college of life science, Capital Normal university, Beijing 100037, china.Institute of Zoology, Chinese Academy of sciences, Beijing 100080, china. [a]college of life science Capital Normal University Beijing China [b]Institute of Zoology Chinese Academy of Sciences Beijing China

In this paper one new genus and one new species of fossil ommatid, Odontomma trachylaena gen. et sp. nov., is described and illustrated from the Late Jurassic or Early Cretaceous Yixian Formation of western Liaoning, china. Based on wide epipleural space of elytron with several rows of cells, the new taxa is attributed to tribe Brochocoleini of Ommatidae and compared with genus Bro-chocoleus. Due to the fact that most other Chinese Mesozoic ommatids are not complete, the complete preservation of the new specimens reported here enabled us to determine the characteristics of the body of these ancient ommatid. Moreover, based on the well-preserved individual of this new genus, we may suppose the affinities of the new species with extant and extinct groups.

关键词： Ommatidae Late Jurassic Early Cretaceous Liaoning Province.

Soluble protein and acid phosphatase exuded by ectomycorrhizal fungi and seedlings in response to excessive Cu and Cd

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Journal of Environmental sciences 2009年第12期21卷 1667-1672页

作者： ZHENG Weishuang, FEI Yingheng, HUANG Yi college of Environmental sciences and Engineering, Peking university, Beijing 100871, china. [a] college of Environmental sciences Engineering Peking University Beijing 100871 China

Fungi and their symbionts can alleviate heavy metal stress by exuding soluble proteins and enzymes. This study examined the role of soluble protein and acid phosphatase （APase） exuded by Xerocomus chrysenteron, an ectomycorrhizal fungus, and the seedlings of its symbiont, Chinese pine （Pinus tabulaeformis）, under conditions of excessive Cu and Cd. The growth type showed that this poorly studied ectomycorrhizal fungus was capable of tolerating high concentrations of Cu, and may be useful in phytoremediation. X. chrysenteron grew well at 80 mg/L Cu, and the EC50 for Cd was 17.82 mg/L. X. chrysenteron also showed enhanced exudation of soluble protein in both isolated and inoculated cultivations under the influence of Cu and Cd. Soluble protein exudation, however, differed under Cu and Cd stress in isolates. In mediums containing Cu, soluble protein exudation increased with concentration, but in mediums containing Cd the content of soluble protein increased to a comparable level at all concentrations. This study demonstrated that soluble protein was related to heavy metal tolerance, although the different ions played different roles. While APase activity in exudates of fungi and seedlings decreased under Cu and Cd stress in comparison to the control, the APase activity in seedlings was maintained by inoculation. Thus, X. chrysenteron facilitated the ability of plant to maintain a normal nutrient uptake, and therefore to protect it from heavy metal toxicity.

关键词： soluble protein acid phosphatase exudate Cu, Cd Xerocomus chrysenteron

Construction of AFLP-based genetic linkage maps for the Chinese shrimp Fenneropaeneus chinensis

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Chinese science Bulletin 2008年第8期53卷 1205-1216页

作者： TIAN Yi1,2,3,4, KONG Jie1↑ & WANG WeiJi1 1 Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery science, Qingdao 266071, china.2 college of life science and Technology, Dalian Fisheries university, Dalian 116023, china.3 Institute of Oceanology, Chinese Academy of sciences, Qingdao 266071, china.4 Graduate university of Chinese Academy of sciences, Beijing 100049, china Chinese Acad Fisheries Sci Yellow Sea Fisheries Res Inst Qingdao 266071 Peoples R China.

Fenneropaeneus chinensis is an important species in marine fishery resources and aquaculture in china. A genetic linkage map is essential for improving the efficiency of its breeding by marker-as- sisted selection and identifying commercially important genes. Linkage maps of F. chinensis were constructed with an F2 mapping population (110 progenies) using amplified fragment length polymor- phic (AFLP) marker in this study. Fifty-five AFLP primer combinations produced 532 AFLP markers fitting for map strategy in mapping family. The markers with 3:1 segregating ratios were analyzed using F2 intercross model for the common linkage map, while the markers with 1:1 ratio were analyzed using the pseudo-testcross strategy. The maps of male, female and common were constructed. The female map included 103 markers that formed 28 linkage groups, covering a total length of 1090 cM. All mark- ers were linked with the linkage groups. Segregation distortion was observed for 6 of 103 markers in the female map. The average distance between markers was 14.53 cM and ranged from 4.4 to 24.8 cM. The male map included 144 markers that formed 35 linkage groups. Ten markers remained unlinked in male map. Segregation distortion was observed for 7 of 144 markers in the male map. The total dis- tance of male map covered 1617 cM. The average distance between markers was 16.36 cM. The male map was 32.6% longer than the female map, which may reflect sex-specific recombination rates in Chinese shrimp. The common map was composed of 216 markers, including in 44 linkage groups covering a total distance of 1772.1 cM. Two markers remained unlinked. No distorted markers of 216 markers were shown in the common map. The distance between markers was 10.42 cM. An average estimated genome size for the Chinese shrimp was 2420 cM, which was consistent with the relative size of the Penaeid genome. The distribution of AFLP markers was relatively even in chromosomes of Chi- nese shrimp maps. The linkage analysis

关键词： AFLP 海洋渔业虾中国

What we have learned from transcript profile analyses of male and female gametes in flowering plants

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science china.life sciences) 2010年第8期53卷 927-933页

作者： XIN HaiPing & SUN MengXiang Key Laboratory of the Ministry of Education for Plant Developmental Biology, college of life science, Wuhan university, Wuhan 430072, china 1. Key Laboratory of the Ministry of Education for Plant Developmental Biology College of Life Science Wuhan University Wuhan 430072 China

Double fertilization is one of the predominant features of sexual reproduction in flowering plants but, because of the physical inaccessibility of gametes, the essential molecular mechanisms in these processes are largely unknown. Based on the techniques for isolating highly purified gametes from several species and well-developed methods for manipulating RNA from limited quantities of gametes, genome-wide investigations of gamete transcription profiles were recently conducted in flowering plants. In this review, we survey the accumulated knowledge on gamete collection and purification, cDNA library construction, and transcript profile analysis to assess our understanding of the molecular mechanisms of gamete specialization and fertilization.

关键词： sperm cell egg cell fertilization cDNA library gametogenesis transcript profile

Genes for resistance to stripe rust on chromosome 2B and their application in wheat breeding

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Progress in Natural science:Materials International 2009年第1期19卷 9-15页

作者： Peigao Luo a,b,Xueyun Hu a,Huaiyu Zhang a,Zhenglong Ren a,b,a State Key Laboratory of Plant Breeding and Genetics,Sichuan agriculture university,Ya’an,Sichuan 625014,china.b School of life science and Technology,university of Electronic science and Technology of china.Chengdu 610054,china [a]State Key Laboratory of Plant Breeding and Genetics Sichuan Agriculture University Ya’an Sichuan 625014 China [b]School of Life Science and Technology University of Electronic Science and Technology of China Chengdu 610054 China

Stripe rust,caused by Puccinia striiformis ***,is one of the most damaging diseases of wheat *** resistant cultivars is the most economic and environmental friendly way to control the *** are many resistance genes to stripe rust located on wheat chromosome ***,we propose a strategy to construct the recombinant wheat chromosome 2B with multiple resistances to stripe rust by making crosses between wheat lines or cultivars carrying Yr genes and using marker-assisted selection,based on the reported information about resistance spectrum,chromosomal location,and linked markers of the *** the resistance genes on 2B would afford a valuable strategy to control the disease by cultivating varieties with durable *** possibility,efficiency,and prospect of the suggested strategy are reviewed in the paper.

关键词： Puccinia striiformis Yr gene 2B chromosome Stripe rust Marker-assisted selection

The feature study on the π and proton rapidity distributions at AGS, SPS and RHIC

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science china.Physics,Mechanics & Astronomy) 2009年第2期52卷 198-206页

作者： FENG ShengQin1,2 & YUAN XianBao1,3 1 college of science, china.Three Gorges university, Yichang 443002, china.2 School of Physics and Technology, Wuhan university, Wuhan 430072, china.3 Institute of Particle Physics, Central china.Normal university, Wuhan 430070, china 1. college of science China Three Gorges University Yichang 443002 China 2. School of Physics and Technology Wuhan University Wuhan 430072 China 3. Institute of Particle Physics Central China Normal University Wuhan 430070 China

The features of nuclear stopping power and multi-hadron production systematically are studied by making an analysis of rapidity distributions of pion and proton at AGS, SPS and RHIC in this work. It is found that nuclear stopping power increases linearly with project rapidity yp at AGS and SPS, but that is not liner at RHIC. It is argued that the average rapidity loss is saturated at central rapidity region at RHIC. For pion distribution, it is found that the phase space of pion distribution distributes uniformly in the longitudinal direction,and a linear relationship of L with log s is given at AGS and SPS. Non-uniform flow model may explain the features of the distribution at AGS and SPS, but may not ex- plain those of at RHIC.

关键词： non-uniform flow model average rapidity loss baryon number density nuclear stopping power