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Application of Equilibrium Partitioning Approach to the Derivation of Sediment Quality Guidelines for Metals in Dianchi Lake

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Pedosphere 2007年第3期17卷 284-294页

作者： CHEN Yun-Zeng YANG Hao ZHANG Zhen-Ke QIN Ming-Zhou JIN Feng LU Jun-Jie Institute of Resources and Environment Henan University Kaifeng 475001 （China） State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil Science Chinese Academy of SciencesNanjing 210008 （China） college of geography Nanjing Normal University Nanjing 210097 （China） Key Laboratory of Coast and Island Development of MOE Nanjing University Nanjing 210093 （China）

For the past 20 years, numerous studies have been carried out on the application of equilibrium partitioning approach （EqPA） for the derivation of sediment quality guidelines （SQGs）. However, for metals, few Equilibrium-partitioning- based numerical SQGs have been developed or are currently available because of the confounding factors mediating the bioavailability of metals. A study was conducted at Dianchi Lake, which is a heavily eutrophicated lake on the Yunnan- Guizhou Plateau, china with the focus on the measurement of partitioning coefficient （Kp） and SQGs derivation and normalization to acid volatile sulfide （AVS）, fine material, and organic carbon. Using new normalization methods, SQGs were formulated for seven metals including copper, zinc, lead, cadmium, chromium, mercury, and arsenic in Dianchi Lake. In Dianchi Lake sediments, the fine material contributed 25.4%-3..0% to the SQG values, with the largest contribution to the SQG value of mercury; AVS contributed 2.9%-75.0% to the SQG values, with the largest contribution to the SQG value of cadmium. This indicated that the fine material and the AVS were the most important controlling factors to the bioavailability of mercury and caximium, respectively. The contribution of total organic carbon （TOC） to the SQG values of copper and leaxi was 3.8% and 7.1%, respectively, indicating that at relatively lower concentrations, the contribution of TOC was not significant. In addition to normalization methods, appropriate procedures for the application of EqPA including sample collection, storage, and analysis are also essential to improve the reliability of SQGs. The normalized Dianchi Lake SQGs were higher than most of the empirically based SQGs developed in North America, but lower than Hong Kong interim SQGs except for cadmium and arsenic. The differences could be attributed to the approaches used for derivation of SQGs and the water quality criteria adopted and the differences in the physical and chemical charac

关键词： acid volatile sulfide fine material normalization method organic carbon sediment quality guidelines

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An Efficient Certificateless Ring Signature Scheme

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Wuhan university Journal of Natural Sciences 2008年第5期13卷 567-571页

作者： ZHU Lijun ZHANG Futai college of Mathematics and Computer Science NanjingNormal University Nanjing 210097 Jiangsu China

To overcome the drawbacks such as high computational cost, unreasonable security model and long signature length in existing certificateless ring signature schemes, we propose an efficient certificateless ring signature scheme in this paper. Our construction is inspired by some efficient ID-based ring signature schemes, and uses bilinear pairings as a basic tool. Using a reasonable security model, the unforgeability of the proposed scheme is proven based on the intractability of the computational Diffie-Hellman （CDH） problem. The signature length of the new scheme is only ｜G2｜＋n｜G1｜（｜Gi｜ is the bit length of an element in group Gi, i =1, 2）. Compared with other existing certificateless ring signature schemes, the newly proposed scheme has a shorter signature length and is more efficient and practical.

关键词： certificateless ring signature unforgeability bilinear pairings CDH problem

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Morroniside protects cultured human umbilical vein endothelial cells from damage by high ambient glucose

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Acta Pharmacologica Sinica 2004年第4期25卷 14-17页

作者： Hui-qin XU2, Hai-ping HAO2, Xu ZHANG3.Yang PAN2 2college of Pharmacy 3.asicMedicine college, nanjing {3.of Traditional ChineseMedicine, nanjing 210029, china college of Pharmacy Basic Medicine college Nanjing University of Traditional Chinese Medicine

AIM: To determine whether morroniside, a compound in Cornus officinalis Sieb et Zucc can prevent cultured human umbilical vein endothelial cells (HUVEC) from damage by high ambient glucose. METHODS: HUVEC was incubated in glucose, 5 or 3. mmol/L, either alone or in the presence of morroniside (final concentration 100, 10, and 1 μmol/L, respectively) for 48 h. The proliferation of HUVEC was quantified by MTT method; its cycle was analyzed by flow cytometry; morphological change was observed with fluorescence microscopy. RESULTS: Survival of HUVEC cultured in high ambient glucose was significantly decreased when compared to that in normal concentration of glucose (P<0.01). High ambient glucose also lowered the rate of cells entering into S-phase, along with severe morphological damage. With the intervention of morroniside (final concentration 100 and 10 μmol/L), the cell survival was significantly recovered (P<0.01, P<0.05, respectively), accompanied with increased S-phase rate and less extent of morphological damage. CONCLUSION: Morroniside protected HUVEC against high ambi- ent glucose induced injury, which suggested that morroniside could exert a beneficial effect on preventing diabetic angiopathies.

关键词： morroniside umbilical veins endothelial cells diabetic angiopathies

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Water Yield and Sediment Yield Simulations for Teba Catchment in Spain Using SWRRB Model: Ⅰ. Model Input and Simulation Experiment

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Pedosphere 2002年第1期12卷 41-48页

作者： ZENG ZHIYUAN and A. M. J. MEIJERINK Collage of geography, nanjing normal university, nanjing 210097 ({3.) International Institute for Aerospace Survey and Earth Sciences, P. O. Box 6, 7500A A Enschede (the Netherlands) Collage of geography Nanjing Normal University Nanjing 210097 International Institute for Aerospace Survey and Earth ScieneesNetherlands) 荷兰

Water yield and sediment yield in the Teba catchment, Spain, weresimulated using SWRRB (Simulator for Water Resources in Rural Basins)model. The model is composed of 198 mathematical equations. About 120items (variables) were input for the simulation, includingmeteorological and climatic factors, hydrologic factors, topographicfactors, parent materials, soils, vegetation, human activities, *** simulated results involved surface runoff, subsurface runoff,sediment, peak flow, evapotranspiration, soil water, total biomass,etc. Careful and thorough input data preparation and repeatedsimulation experiments are the key to get the accurate results. Inthis work in the simulation accuracy for annual water yieldprediction reached to 83.68/100.

关键词： comptuer simulation image processing Spain SWRRB

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Preliminary study on assessment of nutrient transport in the Taihu Basin based on SWAT modeling

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Science china Earth Sciences 2006年第z1期49卷 135-145页

作者： LAI Geying, YU Ge & GUI Feng nanjing Institute of geography & Limnology, Chinese Academy of Sciences, nanjing 210008,{3. The Graduate School of the Chinese Academy of Sciences, Beijing 10003.,{3. Key Lab of Poyang Lake Ecological Environment and Resource Development, Jiangxi normal university, Nanchang 3.0027,{3. 1. nanjing Institute of geography & Limnology Chinese Academy of Sciences Nanjing 210008 China2. The Graduate School of the Chinese Academy of Sciences Beijing 100039 China3. Key Lab of Poyang Lake Ecological Environment and Resource Development Jiangxi Normal University Nanchang 330027 China

With the Taihu Basin as a study area, using the spatially distributed and mechanism-based SWAT model, preliminary simulations of nutrient transport in the Taihu Basin during the period of 1995～2002 has been carried out. The topography, soil, meteorology and land use with industrial point pollution discharge, the loss of agricultural fertilizers, urban sewerage, and livestock drainages were all considered in the boundary conditions of the simulations. The model was calibrated and validated against water quality monitoring data from 2001 to 2002. The results show that the annual total productions of nitrogen (TN) and phosphorus (TP) into Lake Taihu are 40000t and 2000t respectively. Nutrient from the Huxi Region is a major resource for Lake Taihu. The non-point source (surface source) pollution is the main form of catchment sources of nutrients into Lake Taihu,occupied TN 53. and TP 56% respectively. TN and TP nutrients from industrial point pollution discharge are 3.% and 16%, and sewerage in both forms of point source and non-point source are TN 3.% and TP 47%. Both the loss of agricultural fertilizers and livestock drainages from the catchment should be paid more attention as an important nutrient source. The results also show that SWAT is an effective model for the simulation of temporally and spatially nutrient changes and for the assessment of the trends in a catchment scale.

关键词： Taihu Basin, nutrients, catchment resource inputs, SWAT model, simulation.

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Bacterial Communities in a Buried Ancient Paddy Soil from the Neolithic Age

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Pedosphere 2010年第3期20卷 389-398页

作者： SHEN Wei-Shou YIN Rui LIN Xian-Gui CAO Zhi-Hong State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil Science Chinese Academy of SciencesNanjing 210008 (China) college of Chemistry and Environmental Science Nanjing Normal University Nanjing 210097 (China) Joint Open Laboratory of Soil and Environment Institute of Soil Science Chinese Academy of Sciences and Hong KongBaptist University Nanjing 210008 (China)

An ancient irrigated paddy soil from the Neolithic age was excavated at Chuodunshan Site in the Yangtze River Delta, close to Suzhou, china. The soil organic matter (SOM) content in the prehistoric rice soil is comparable to the average SOM content of present rice soils in this region, but it is about 5 times higher than that in the parent materials. As possible biomarkers to indicate the presence of the prehistoric paddy soil, the bacterial communities were investigated using the techniques of aerobic and anaerobic oligotrophic bacteria enumeration, Biolog analysis, and polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE). The results showed that in the buried soil layers, the prehistoric paddy soil had the largest number of aerobic and anaerobic oligotrophic bacteria, up to 6.12 and 5.86 log cfu g-1 dry soil, respectively. The prehistoric paddy soil displayed better carbon utilization potential and higher functional diversity compared to the parent materials and a prehistoric loess layer. The Shannon index and richness based on DGGE profiles of bacterial 16S rRNA genes were higher in prehistoric paddy soil than those in the prehistoric loess soil. It might be concluded that the prehistoric irrigated rice cultivation accumulated the SOM in plowed soil layer, and thus increased soil bacterial populations, metabolic activity, functional diversity and genetic diversity. Bacterial communities might be considered as the sensitive indicators of the presence of the prehistoric paddy soil in china's Yangtze River Delta.

关键词： biomarker denaturing gradient gel electrophoresis oligotrophic bacteria paleosols prehistoric paddy soil

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Aberrant expression and function of TCF4 in the proliferation of hepatocellular carcinoma cell line BEL-7402

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Cell Research 2004年第1期14卷 74-80页

作者： Dong Hong ZHAO, Jian Jun HONG, Shi Ying GUO, Run Lin YANG, Jun YUAN, Chuan Jun WEN, Kai Ya ZHOU, Chao Jun LI~* The Jiangsu Key Laboratory of Molecular Medical Biotechnology, college of Life Science, nanjing normal university, nanjing 210097, Jiangsu,{3.. Li CJ Nanjing Normal Univ Coll Life Sci Jiangsu Key Lab Mol Med Biotechnol Nanjing 210097 Peoples R China

Wnt signaling pathway is essential for development and tumorigenesis, however, this signaling pathway in the progress of hepatocellular carcinoma (HCC) remains unclear. In this paper, we studied the function of human T-cell transcription factor-4 (TCF4), a key factor of Wnt signaling pathway, on the proliferation of HCC cell line. We showed that the expression of TCF4 mRNA in HCC cell line BEL-7402 was higher than that in immortalized normal liver cell line L02. Blockage of Wnt pathway by △NTCF4, a dominant negative TCF4, could suppress BEL-7402 cells growth and decrease the expression of cyclin D1 and c-myc, two of target genes of Wnt pathway. On the other hand, stimulating Wnt pathway by introducing a degradation-resistant β-catenin S3.A could increase BEL-7402 cells proliferation. But all the treatments had no effect on L02 cells. Our data indicated that TCF4 might be another key factor in Wnt pathway involved in HCC cells proliferation and TCF4 could be an effective therapeutic target for suppress

关键词： Wnt signaling pathway β-catenin dominant negative TCF4.

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Contourlet HMT model with directional feature

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Science china(Information Sciences) 2012年第7期55卷 1563-1578页

作者： WANG XiangHai 1,2,3.,CHEN MingYing 1 ,SONG ChuanMing 1,2 ,XU MengChun 1 & FANG LingLing 3.1 college of Computer and Information Technology,Liaoning normal university,Dalian 116029,{3. 2 State Key Laboratory for Novel Software Technology,nanjing university,nanjing 210093.{3. 3.Provincial Key Laboratory for Computer Information Processing Technology,Soochow university,Suzhou 215006,{3. 1. college of Computer and Information Technology Liaoning Normal University Dalian 116029 China2. State Key Laboratory for Novel Software Technology Nanjing University Nanjing 210093 China3. Provincial Key Laboratory for Computer Information Processing Technology Soochow University Suzhou 215006 China

According to Shanno's information theory,the directional feature of texture is defined as the value of directional variable when an image signal attains a singularity of random *** terms of this definition,we calculate the texture's directional features using Tamura's method and study the directional probability distribution of Contourlet *** we find that the directional features tend to be conveyed across parent and child *** on this conclusion,we establish a novel probability distribution model of hidden direction variables under the condition of hidden state variable's distribution,named Contourlet HMT model with directional *** structure and training method of the model are presented as ***,an unsupervised context-based image segmentation algorithm is proposed on the basis of the proposed *** effectiveness is verified via extensive experiments carried out on several synthesized images and remote sensing images.

关键词： directional feature Contourlet HMT Contourlet HMT with directional feature unsupervised texture segmentation

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Sonochemical effect of a bifrequency irradiation

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Chinese Science Bulletin 2000年第2期45卷 142-145页

作者： ZHU Changping, FENG Ruo & ZHAO Yiyun Department of Physics. Jingzhou normal college, Jingzhou 43.100, china State Key Laboratory of Modern Acoustics, {3. university, {3. 210093. china Chemistry Department of Yunnan university, Kunming 650091, Ch Department of Physics Jingzhou Normal College Jingzhou China State Key Laboratory of Modern Acoustics Nanjing University Nanjing China Chemistry Department of Yunnan university Kunming China

The sonochemical effect of a bifrequency orthogonal ultrasonic irradiation has been studied by using two different detecting methods. It has been shown that the sonochemical yield produced by the bifrequency irradiation appears to be much more than the sum of the yields produced separately by the two irradiations. The bifrequency irradiation, therefore, can be expected to exert a great influence on the development of sonohemical

关键词： bifrequency sonochemistry effect.

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Abrupt climate change of EastAsian Monsoon at 13. kaBP inferred from a high resolu-tion stalagmite δ18O record

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Science Bulletin 2005年第23期50卷 2765-2769页

作者： JIANG Xiuyang1, WANG Yongjin1, KONG Xinggong1,WU Jiangying1, SHAO Xiaohua1, XIA Zhifeng1 & CHENG Hai2 1. college of geography Science, nanjing normal university, {3.210097, china 2. Department of Geology and Geophysics, university of MinnesotaMinneapolis, MN 55455, USA college of geography Science Nanjing Normal University Nanjing 210097 China Department of Geology and Geophysics University of Minnesota Minneapolis MN 55455 USA

23.Th ages and oxygen isotope data of a stalagmite from Shanbao Cave in Hubei Province characterize thEast Asian Monsoon precipitation from 13. to127 ka. Thdecadal-scale high-resolution δ18O record reveals a detailedtransitional process from the Penultimate Glaciation to thLast Interglaciation. As established with 23.Th dates, the agof the Termination II is determined to be 129.5±1.0 kaBPwhich supports the Northern Hemisphere insolation as thtriggers for the ice-age cycles. In our δ18O record, the glacialinterglacial fluctuation reaches about 4‰, almost the samlevel as in other Asian Monsoon cave stalagmite δ18O recordThe transition of the glacial/interglacial period in our recordcan be recognized as four stepwise stages, among which, arapid rise of monsoon precipitation follows the stage o“Termination II pause”. The rapid rise is synchronous withthe abrupt change of global methane concentration, whichreflects that an increase in both Asian Monsoon precipitationand tropical wetland plays an important role in the globaclimate changes.

关键词： stalagmite high-resolution U/Th age Termination II.

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