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Changes in enzymes activity, substrate utilization pattern and diversity of soil microbial communities under cadmium pollution

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Journal of Environmental Sciences 2005年第5期17卷 802-807页

作者： Muhammad Akmal WANG Hai-zhen wu jian-jun XU jian-ming XU De-fu Institute of Soil and grater Resources and Environmental Science Zhejiang University Hangzhou 310029 China

Heavy metal pollution has received increasing attention in recent years mainly because of the public awareness of environmental issues. In this study we have evaluated the effect of cadmium （Cd） on enzymes activity, substrate utilization pattern and diversity of microbial communities in soil spiked with 0, 20, 40, 60, 80, and 100 mg/kg Cd, during 60 d of incubation at 25℃. Enzyme activities determined at 0, 15, 30, 45, and 60 d after heavy metal application（DAA） showed marked declines for various Cd treatments, and up to 60 DAA, 100 mg/kg Cd resulted in 50.1%, 47.4%, and 39.8% decreases in soil urease, acid phosphatase and dehydrogenase activities, respectively to control. At 60 DAA, substrate utilization pattern of soil microbial communities determined by inoculating Biolog ECO plates indicated that Cd addition had markedly inhibited the functional activity of soil microbial communities and multivariate analysis of sole carbon source utilization showed significantly different utilization patterns for 80 and 100 mg/kg Cd treatments. The structural diversity of soil microbial communities assessed by PCR-DGGE method at 60 DAA, illustrated that DGGE patterns in soil simplified with increasing Cd concentration, and clustering of DGGE profiles for various Cd treatments revealed that they had more than 50% difference with that of control.

关键词： enzyme activity microbial community soil cadmium

The Stability of Multi-modal Traffic Network

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Communications in Theoretical Physics 2013年第7期60卷 48-54页

作者： HAN Ling-Hui Sun Hui-jun ZHU Cheng-Juan wu jian-jun JIA Bin MOE Key Laboratory for Urban Transportation Complex Systems Theory Beijing Jiaotong University Beijing 100044 China State Key Laboratory of Rail Traffic Control and Safety Beijing Jiaotong University Beijing 100044 China

There is an explicit and implicit assumption in multimodal traffic equilibrium models, that is, if the equilibrium exists, then it will also occur. The assumption is very idealized; in fact, it may be shown that the quite contrary could happen, because in multimodal traffic network, especially in mixed traffic conditions the interaction among traffic modes is asymmetric and the asymmetric interaction may result in the instability of traffic system. In this paper, to study the stability of multimodal traffic system, we respectively present the travel cost function in mixed traffic conditions and in traffic network with dedicated bus lanes. Based on a day-to-day dynamical model, we study the evolution of daily route choice of travelers in multimodal traffic network using 10000 random initial values for different cases. From the results of simulation, it can be concluded that the asymmetric interaction between the cars and buses in mixed traffic conditions can lead the traffic system to instability when traffic demand is larger. We also study the effect of travelers' perception error on the stability of multimodal traffic network. Although the larger perception error can alleviate the effect of interaction between cars and buses and improve the stability of traffic system in mixed traffic conditions, the traffic system also become instable when the traffic demand is larger than a number. For all cases simulated in this study, with the same parameters, traffic system with dedicated bus lane has better stability for traffic demand than that in mixed traffic conditions. We also find that the network with dedicated bus lane has higher portion of travelers by bus than it of mixed traffic network. So it can be concluded that building dedicated bus lane can improve the stability of traffic system and attract more travelers to choose bus reducing the traffic congestion.

关键词： multi-modal traffic network day-to-day dynamical model stability

Comparison of patients by family history with gastric and non-gastric cancer

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World Journal of Gastroenterology 2009年第21期15卷 2644-2650页

作者： Xue-Fu Zhou Yu-Long He wu Song jian-jun Peng Chang-Hua Zhang Wen Li Hui wu Department of Gastrointestinal Surgery The First Affiliated Hospital Sun Yat-Sen University Guangzhou 510080 Guangdong Province China

AIM:To compare the gastric cancer(GC) patients by their family history with gastric and ***:Positive family histories within seconddegree relatives and clinicopathological features were obtained for 256 ***:Of the 256 probands,112(76 male,36 female) were incorporated into familial GC(FGC) group:at least two GC members;144(98 male,46 female) were included in the non-FGC group(relatives only affected with non-GCs).Of 399 tumors in relatives(181 from FGC against 212 from non-FGC),GC was the most frequent,followed by esophageal,hepatocellular,and colorectal *** cancer was next to lung cancer but prior to breast and urogenital *** affected members aggregated within first-degree relatives(FGC:66 siblings,48 fathers,31 mothers,four offspring;non-FGC:56 fathers,55 siblings,43 mothers,and 15 offspring).The ratio of males to females in affected first-degree relatives was usually higher in male *** history of GC was a slight risk for GC in males(OR = 1.19,95% CI:0.53-2.69),while risk of GC by maternal history of non-GCs was increased in females(OR = 0.46,95% CI:0.22-0.97).Diffuse-GC was the major histological type in all *** in tumor sites between thetwo groups was derived from an excess of upper sites in non-FGC female ***:Distribution of associated non-GCs in a family history of GC may vary with geographic *** may have different genetic and/or environmental etiology in different families,and a certain subtype may be inherited in a female-influenced fashion.

关键词： Gastric cancer Family history Familialgastric cancer Familial predisposition Female-influencedfashion

4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone Induces Circulating MicroRNA Deregulation in Early Lung Carcinogenesis

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Biomedical and Environmental Sciences 2014年第1期27卷 10-16页

作者： wu jian jun YANG Ti LI Xun XIA Yuan ZHAO Yao ZOU Fei jianG Yi Guo School of Public Health and Tropical Medicine Southern Medical University Institute for Chemical Carcinogenesis State Key Laboratory of Respiratory DiseaseGuangzhou Medical University School of Public Health Guangdong Pharmaceutical University

Objective To study the alteration of circulating microRNAs in 4-（methylnitrosamino）-l-（3-pyridyl） -l-butanone （NNK）-induced early stage lung carcinogenesis. Methods A lung cancer model of male F344 rats was induced with systemic NNK and levels of 8 lung cancer-associated miRNAs in whole blood and serum of rats were measured by quantitative RT-PCR of each at weeks 2, 5, 20, and 20 following NNK treatment. Results No lung cancer was detected in control group and NNK treatment group at week 20 following NNK treatment. The levels of some circulating miRNAs were significantly higher in NNK treatment group than in control group. The miR-210 was down-regulated and the miR-206 was up-regulated in NNK treatment group. The expression level of circulating miRNAs changed from week 1 to week 20 following NNK treatment. Conclusion The expression level of circulating miRNAs is related to NNK-induced early stage lung carcinogenesis in rats and can therefore serve as its potential indicator.

关键词： NNK Circulating microRNA Early stage Lung carcinogenesis

Response of Rice Varieties to Bound Residues of Metsulfuron-Methyl in a Paddy Soil

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Pedosphere 2007年第4期17卷 487-492页

作者： LI Zhao-jun WANG Hai-Zhen XU jian-Ming wu jian-jun MA Guo-Rui Institute of Soil and Water Resources and Environmental Science Zhejiang University Hangzhou 310029 （China）. Institute of Agricultural Resources and Regional Planning Ministry of Agriculture Key Laboratory of Plant Nutrition and Nutrient Cycling Chinese Academy of Agricultural Sciences Beijing 100081 （China）

Metsulfuron-methyl is one of the widely used sulfonylurea herbicides. However, approximately half of the applied metsulfuron-methyl may remain as bound residues in soil. To characterize the response of rice plants to residual metsulfuron-methyl in soil, the activities of acetolactate synthase （ALS）, superoxide dismutase （SOD）, peroxidase （POD）, and catalase （CAT） were investigated in two rice varieties that differed in susceptibility to the herbicide. Changes in the activity of these enzymes in leaves and roots of Xiushui 63, a sensitive rice variety, were greater than those in a resistant variety Zhenong 952. Irrespective of variety, changes in the enzyme activity were greater in the roots than in the leaves. The activities of ALS and CAT decreased, while the SOD activity increased with the increase in the amounts of bound residues of metsulfuron-methyl （BRM） in soil. The POD activity increased at the BRM level of 0.025 mg kg^-1, but decreased at the BRM level of 0.05 mg kg^-1. The results showed that the bound residues of sulfonylurea herbicides may affect metabolism of rice plants.

关键词： ALS activity bound residues CAT activity metsulfuron-methyl SOD activity

Equilibrium analysis of mixed passengers in urban railway network

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Journal of Central South University 2016年第6期23卷 1535-1540页

作者：张璐吴建军孙会君 State Key Laboratory of Rail Traffic Control and Safety (Beijing Jiaotong University) Beijing 100044 China School of Traffic and Transportation Beijing Jiaotong University Beijing 100044 China

A model is proposed to describe the passengers’route choice behaviors in urban railway traffic with stochastic link capacity degradation by considering two types of demand,sensitive and insensitive *** insensitive passengers choose their route without paying much attention to *** the contrary,sensitive passengers who consider route congestion choose travel route based on generalized *** equilibrium state is given by variational inequalities in terms of travel generalized cost,which is represented by the combinations of mean and variance of total travel *** diagonalization algorithm is given to solve this *** show that insensitive passengers have large effects on the path choice than sensitive ones,especially for the larger demand.

关键词： mixed passengers urban railway network capacity degradation equilibrium

Robust user equilibrium model based on cumulative prospect theory under distribution-free travel time

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Journal of Central South University 2015年第2期22卷 761-770页

作者：王伟孙会君吴建军 Key Laboratory for Urban Transportation Complex Systems Theory of Ministry of Education(Beijing Jiaotong University) State Key Laboratory of Rail Traffic Control and Safety (Beijing Jiaotong University)

The assumption widely used in the user equilibrium model for stochastic network was that the probability distributions of the travel time were known explicitly by travelers. However, this distribution may be unavailable in reality. By relaxing the restrictive assumption, a robust user equilibrium model based on cumulative prospect theory under distribution-free travel time was presented. In the absence of the cumulative distribution function of the travel time, the exact cumulative prospect value(CPV) for each route cannot be obtained. However, the upper and lower bounds on the CPV can be calculated by probability *** were assumed to choose the routes with the best worst-case CPVs. The proposed model was formulated as a variational inequality problem and solved via a heuristic solution algorithm. A numerical example was also provided to illustrate the application of the proposed model and the efficiency of the solution algorithm.

关键词： user equilibrium cumulative prospect theory distribution-free travel time variational inequality

Two-stent strategy for renal artery stenosis with bifurcation lesion

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2010年第8期11卷 561-567页

作者： Hong-bing YAN Bin ZHENG Zheng wu jian WANG Han-jun ZHAO Li SONG Yun-peng CHI Department of Cardiology Beijing Anzhen Hospital Capital Medical University Beijing 100029 China

Renal artery stenosis(RAS) with a bifurcation lesion is a challenge for interventional *** aim of this study is to summarize our experience in RAS with a bifurcation *** patients with RAS involving bifurcation lesion are *** cases 1 to 3,a single-stent strategy was first ***,these three patients were converted to a two-stent strategy for bailout stent implantation in the side *** cases 4 and 5,a simultaneous kissing stent technique was *** showed that the reference vascular diameter of the main branch was much larger than those of the side *** obvious residual stenosis existed in cases 1 to 3 after stent implantation,no obvious residual stenosis was seen in cases 4 and *** artery duplex sonography was performed in cases 1 through 5 at 6,7,7,8,and 6 months,respectively,after the *** evidence of restenosis or occlusion was *** conclusion,stent implantation with the simultaneous kissing stent technique may result in more simple and more satisfactory immediate angiographic results.

关键词： Peripheral atherosclerotic artery disease Angioplasty Stents Renal artery stenosis

Rubus chingii Hu: an overview of botany, traditional uses,phytochemistry, and pharmacology

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Chinese Journal of Natural Medicines 2020年第6期18卷 401-416页

作者： SHENG Jia-Yun WANG Si-Qi LIU Kao-Hua ZHU Bo ZHANG Qiao-Yan QIN Lu-Ping wu jian-jun School of Pharmacy Zhejiang Chinese Medical UniversityHangzhou 310053China

Rubus chingii Hu, a member of the rosaceae family, is extensively distributed in China and Japan. Its unripe fruits(Fupenzi in Chinese) have a long history of use as an herbal tonic in traditional Chinese medicine for treating various diseases commonly associated with kidney deficiency, and they are still in use today. Phytochemical investigations on the fruits and leaves of R. chingii indicate the presence of terpenoids, flavonoids, steroids, alkaloids, phenylpropanoids, phenolics, and organic acids. Extracts or active substances from this plant are reported to have various pharmacological properties, including antioxidant, anti-inflammatory, antitumor, antifungal, antithrombotic, antiosteoporotic, hypoglycemic, and central nervous system-regulating effects. This review provides up-to-date information on the botanical characterizations, traditional usages, chemical constituents, pharmacological activities, toxicity,and quality control of R. chingii. Possible directions for future research are also briefly proposed. This review aims to supply fundamental data for the further study of R. chingii and contribute to the development of its clinical use.

关键词： Rubus chingii Hu Botany Traditional uses Phytochemistry Pharmacology Review