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Assessment of candidate plant DNA barcodes using the Rutaceae family

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Science china(Life Sciences) 2010年第6期53卷 701-708页

作者： LUO Kun1,2,CHEN ShiLin1,CHEN KeLi2,SONG JingYuan1,YAO Hui1,MA XinYe1,ZHU YingJie3,PANG XiaoHui1,YU Hua1,LI XiWen1,4 & LIU Zhen2 1institute of Medicinal Plant Development,peking Union medical College,Chinese Academy of medical Sciences,beijing 100193,china 2College of Pharmacy,Hubei university of Chinese Medicine,Wuhan 430061,china 3school of Bioscience and engineering,Southwest Jiaotong university,Chengdu 610031,china 4Department of Chemistry,Tsinghua university,beijing 100084,china institute of Medicinal Plant Development Peking Union Medical College Chinese Academy of Medical Sciences Beijing China College of Pharmacy Hubei University of Chinese Medicine Wuhan China school of Bioscience and engineering Southwest Jiaotong University Chengdu China Department of Chemistry Tsinghua University Beijing China

DNA barcoding is a rapidly developing frontier technology that is gaining worldwide ***,seven regions (psbA-trnH,matK,ycf5,rpoC1,rbcL,ITS2,and ITS) with potential for use as DNA barcodes were tested for their ability to identify 300 samples of 192 species from 72 genera of the family *** evaluate each barcode’s utility for species authentication,PCR amplification efficiency,genetic divergence,and barcoding gaps were *** found that the ITS2 region exhibited the highest inter-specific divergence,and that this was significantly higher than the intra-specific variation in the "DNA barcoding gap" assessment and Wilcoxon two-sample *** ITS2 locus had the highest identification efficiency among all tested *** a previous study,we found that ITS2 was able to discriminate a wide range of plant taxa,and here we confirmed that ITS2 was also able to discriminate a number of closely related ***,we propose that ITS2 is a promising candidate barcode for plant species identification.

关键词： DNA barcoding ITS2 Rutaceae identification

Modified HDDR Process for Producing Anisotropic NdFeB Powders

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Journal of university of Science and Technology beijing 2001年第2期8卷 111-114页

作者： Xubo Liu, Yue Ming, Yaofu Xiao, Qi Zeng, Zhengyi Zhang, Run Wang (Material Science and engineering school, university of Science and Technology beijing, beijing 100083, china) (beijing institute of Aeronautical Materials, beijing 100095, china) Material Sci. and engineering school University of Science and Technology Beijing 100083 China

The effect of HDDR (hydrogenation-decomposition-desorption-recombination process) treating conditions on magnetic anisotropy of Nd13FebalCo17B7Ga1Zr0.1 powders has been studied. It is found that increasing recombination temperature is effective for magnetic anisotropy formation, but at the cost of reducing the coercive force. The microstructure analysis (TEM) indicates that the NdFeB recombination nucleation takes place markedly during the transition range from decomposition stage to recombination stage, in which both temperature and H-2 pressure change sharply. In order to create a more stable treatment condition for recombination nucleation, a modified HDDR process is established in which the conventional continuous transition range is divided into several stages. The experimental results have proved that such a process can effectively enhance the remanence of the magnet powders with high certainty, while only cause a little reduction in coercivity.

关键词： HDDR anisotropy NdFeB

Dilatancy equation of rockfill material under the true triaxial stress condition

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Science china(Technological Sciences) 2011年第S1期54卷 175-184页

作者： XIAO Yang 1,2,LIU HanLong 1,2,ZHU JunGao 1,2 & SHI WeiCheng 1,3 1 Key Laboratory of Ministry of Education for Geomechanics and Embankment engineering,Hohai university,Nanjing 210098,china 2 Geotechnical research institute,Hohai university,Nanjing 210098,china 3 school of Civil engineering and Architecture,Changzhou institute of Technology,Changzhou 213002,china Key Laboratory of Ministry of Education for Geomechanics and Embankment engineering Hohai University Nanjing China Geotechnical research institute Hohai University Nanjing China school of Civil engineering and Architecture Changzhou Institute of Technology Changzhou China

Rockfill material is widely used for construction of high rockfill dam due to its facility,economical cost,high strength and effective aseismatic *** is provoked profoundly to propose a suitable constitutive model for a better application of this *** dilatancy equation of rockfill material plays a significant role in the constitutive *** the sake of simplicity,a dilatancy equation is established by the linear least square method on the basis of the rearranged data of rockfill material in the true triaxial *** on the fact that the rearranged data at different initial confining pressures are aligned in a narrow band,the dilatancy behavior of rockfill material is independent of the initial confining ***,different from the initial confining pressure,both the intermediate principal stress ratio and the specimen density exhibit a remarkable influence on the dilatancy behaviors of rockfill ***,the predictions of the proposed dilatancy equation are in a good agreement with the rearranged test data of rockfill material at different specimen densities and stress paths.

关键词： rockfill material dilatancy equation true triaxial test density stress path initial confining pressure

The effect of silica nanoparticle aggregates on wax dissolution in diesel oil

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Petroleum Science 2011年第2期8卷 207-210页

作者： Sun Renyuan Wang Lei Sun Chao Lin Lei Jiang Hanqiao school of Petroleum engineering China University of Petroleum Qingdao Shandong 266555 China institute of Drilling ＆ Production Technology Jidong Oilfield Tangshan Hebei 063004 China Xianhe Oil Production Plant Shengli Oilfield Dongying Shandong 257000 China school of Petroleum engineering China University of Petroleum Beijing 102249 China

In recent years, silica nanoparticle aggregates （SNPAs） have been used to decrease the injection pressure of wells in low permeability reservoirs achieving good results. In order to study the mechanisms for reduction in the injection pressure of low permeability wells by the SNPA-diesel oil system injection, the microstructure of SNPAs was observed with a transmission electron microscope （TEM）. The particle size distribution of SNPAs was also measured by the laser scattering method. The viscosities of diesel oil and SNPA-diesel oil system were measured with a capillary viscometer. The effect of SNPAs on the solubility of wax in the diesel oil was experimentally studied. The influencing factors, including temperature and SNPA concentration in diesel oil, on wax solubility were analyzed. A pore-throat film displacement model （PTFDM） was built for mechanism explanation. The microstructure and size distribution analyses show that the SNPAs are in the nanometer size range. The viscosity of the SNPA-diesel oil system is lower than that of the diesel oil. The solubility of wax in the diesel oil increases greatly due to SNPA addition, the solubility ratio reaches 7.5. The solubility of wax in diesel oil increases with increases in the concentration of SNPAs in the diesel oil and with the temperature. It is proved that the addition of SNPAs to diesel oil helps remove the wax deposited near the wellbore. This maybe one of the main mechanisms for injection pressure decreases in low permeability reservoirs.

关键词： Silica nanoparticle aggregates solubility of wax low permeability reservoir pore-throatfilm displacement model injection pressure

Towards a degradation-based mechanism for adaptive overload control

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Science china(Information Sciences) 2012年第12期55卷 2708-2722页

作者： WANG ZiYou 1,2,ZHOU MingHui 1,2 & MEI Hong 1,2 1 Software institute,school of Electronics engineering and Computer Science,peking university,beijing 100871,china 2 Key Laboratory of High Confidence Software Technologies(peking university),Ministry of Education,beijing 100871,china Software institute School of Electronics Engineering and Computer Science Peking University Beijing China Ministry of Education Key Laboratory of High Confidence Software Technologies (Peking University) Beijing China

Uncontrolled overload is one of the major causes of the system's decline in reliability and performance for web *** also harms the construction of trustworthy *** paper presents a degradationbased mechanism to adaptively control overload in complex,dynamic web *** our mechanism,the bottlenecks in the application's performance are determined by internally monitoring the performance and resource utilization state of the application,which is decomposed into a set of *** locating the bottlenecks,two decision algorithms are proposed to dynamically and adaptively generate proper degradation plans without *** degrading the service which consumes critical resources and has a low priority from the perspective of business logic,the application can keep providing key services even when overload *** implement a prototype and conduct a case study on a wiki *** also evaluate our approach and demonstrate its effectiveness in simulated overload *** handling overload,we make a breakthrough in building trustworthy software in an open,dynamic and rapidly changing environment.

关键词： overload service degradation resource monitoring performance management

Effects of binders on the performance of electric double-layer capacitors of carbon nanotube electrodes

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Progress in Natural Science:Materials International 2005年第5期15卷 453-457页

作者： LI Chensha1*, WANG Dazhi1, ZHANG Baoyou2, WANG Xiaofeng1, CAO Maosheng3 and LIANG Ji1(1. Department of Mechanical engineering, Tsinghua university, beijing 100084, china 2. Center for Analysis and Measurement, Harbin institute of Technology, Harbin 150001, china 3. school of Material Science and engineering, Tsinghua university, beijing 100084, china) Dept. of Mech. Eng. Tsinghua Univ. Beijing 100084 China Ctr. for Analysis and Meas. Harbin Inst. of Technol. Harbin 150001 China Sch. of Mat. Sci. and Eng. Tsinghua Univ. Beijing 100084 China

Polarizable electrodes of electric double layer capacitor (EDLCs) were made from carbon nanotubes. Effects of different binders, which are phenolic resin (PF) and polytetrafluoroethylene (PTFE), on the properties of polarizable electrodes are studied. Results indicate that the microstructure, pore size distribution and specific capacitance of the electrodes with PTFE binder are superior to those electrodes with PF binder after carbonization. The suitable binder (PTFE) for carbon nanotubes electrodes is proposed.

关键词： carbon nanotubes electric double-layer capacitors phenolic resin polytetrafluoroethylene.

Receptor subtype involved in α-adrenergic receptor-mediated Ca2+ signaling in cardiomyocytes

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Acta Pharmacologica Sinica 2007年第7期 968-974页

作者： Da-li LUO~(2,3,4),Jian GAO~2,Lin-lin FAN~2,Yu TANG~2,You-yi ZHANG~3,Qi-de HAN~3~2 Department of Pharmacology,school of Chemical Biology and Pharmaceutical Sciences,Capital university of medical Sciences,beijing100069,china ~3 institute of cardiovascular Science at the Health Science Center,peking university,beijing 100083,china

Aim:The enhancement of intracellular Ca2+signaling in response to α1-adrener-gic receptor （α1-AR） stimulation is an essential signal transduction event in theregulation of cardiac functions,such as cardiac growth,cardiac contraction,andcardiac adaptation to various *** present study was intended todetermine the role（s） of the α1-AR subtype（s） in mediating this ***:We evaluated the effects of subtype-specific agonists and antagonists of the α1-AR on the intracellular Ca2+signaling of neonatal rat ventricular myocytes usinga confocal ***:After being cultured for 48 h,the myocytesexhibited spontaneous local Ca2+release,sparks,and global Ca2+*** of the α1-AR with phenylephrine,a selective agonist of the α1-AR,dose-dependently increased the frequency of Ca2+transients with an EC50valueof 2.3 μmol/*** the α1A-AR subtype with 5-methylurapidil （5-Mu） inhi-bited the stimulatory effect of phenylephrine with an IC50value of 6.7 nmol/***,blockade of the α1B-AR and α1D-AR subtypes with chloroethylclonidineand BMY 7378,respectively,did not affect the phenylephrine ***,thelocal Ca2+spark numbers were also increased by the activation of the α1-AR,andthis effect could be abolished selectively by *** importantly,A61603,anovel selective α1A-AR agonist,mimicked the effects of phenylephrine,but withmore potency (EC50value=6.9 nmol/L) in the potentiation of Ca2+transients,andblockade of the α1A-AR by 5-Mu caused abolishment of its ***:These results indicate that α1-adrenergic stimulation of intracellular Ca2+activityis mediated selectively by the α1A-AR.

关键词： α1-adrenergic receptor subtype cardiomyocyte Ca2+ signaling A61603

Transgenic expression of DwMYB2 impairs iron transport from root to shoot in Arabidopsis thaliana

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Cell research 2006年第10期16卷 830-840页

作者： Yan-Hong Chen~(1,2,3) Xue-Min Wu~5 Hong-Qing Ling~4 Wei-Cai Yang~1 ~1The Key Laboratory of Molecular and Developmental Biology,institute of Genetics and Developmental Biology,Chinese Academy of Sciences,beijing 100101 china ~2Graduate university of the Chinese Academy of Sciences,19 Yuquan Road,beijing 100049,china ~3school of Life Science,Nantong university,Nantong 226007 china ~4The State Key Laboratory of Plant Cell and Chromosome engineering,institute of Genetics and Developmental Biology,Chinese Academy of Sciences,beijing 100101,china The Key Laboratory of Molecular and Developmental Biology Institute of Genetics and Developmental Biology Chinese Academy of Sciences Beijing China Graduate university of the Chinese Academy of Sciences Beijing China school of Life Science Nantong University Nantong China Department of Botany University of British Columbia 6270 University Blvd. Vancouver Canada The State Key Laboratory of Plant Cell and Chromosome engineering Institute of Genetics and Developmental Biology Chinese Academy of Sciences Beijing China

In plant,iron uptake and homeostasis are tightly regulated to ensure its absorption from soil and to avoid excessiron in the *** genes involved in this process have been identified during past several years,but there are manyproblems remain unsolved in the genetic regulation of whole plant iron trafficking and *** transcriptionfactors contain tandem repeats of a～50 amino acid DNA-binding motif (R) and are involved in the regulation of manyaspects of plant development,hormone signaling and ***,we report that the ectopic expression of orchidR2R3-MYB gene DwMYB2 in Arabidopsis thaliana confers the transgenic plants hypersensitivity to iron *** DwMYB2 transgenic plants,the iron content in root is two-fold higher compared to that in wild-type root,while thereverse is true in *** imbalance of iron content in root and shoot suggested that the translocation of iron fromroot to shoot was affected by the expression of DwMYB2 in the transgenic ***,gene chip and reversetranscription-polymerase chain reaction analysis revealed that the ferric-chelate reductase gene,AtFRO2,and the irontransporter gene,AtIRT1 and AtIRT2,are up-regulated by DwMYB2 expression,while other potential iron transporterssuch as AtIREG1,AtFRD3 and NRAMP1 are *** addition,the expression of several putative peptidetransporters and transcription factors are also altered in the 35S::DwMYB2 transgenic *** data provide us insightinto the whole plant translocation of iron and identify candidate genes for iron homeostasis in plants despite the fact thata heterologous gene was expressed.

关键词： DwMYB2 iron uptake and homeostasis iron transporters Arabidopsis

A constitutive model of frozen soil with damage and numerical simulation for the coupled problem

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Science china(Physics,Mechanics & Astronomy) 2010年第4期53卷 699-711页

作者： ZHU ZhiWu, NING JianGuo& MA Wei 1 school of Mechanics and engineering, Southwest Jiaotong university, Chengdu 610031, china 2 State Key Laboratory of Explosion Science and Technology, beijing institute of Technology, beijing 100081, china 3 Key Laboratory of Frozen Soil engineering, CAREERI, CAS, Lanzhou 730000, china school of Mechanics and engineering Southwest Jiaotong University Chengdu China State Key Laboratory of Explosion Science and Technology Beijing Institute of Technology Beijing China Key Laboratory of Frozen Soil engineering CAREERI CAS Lanzhou China

Based on the microcosmic mechanics of composite materials, an elastic constitutive model for frozen soil with damage is presented. For frozen sandy soil with a range of ice contents and under a range of temperature conditions, quantitative results determined by this constitutive model agree with practically measured stress-strain curves. After numerically simulating the coupled water, temperature and stress fields of channel frozen and frozen roadbed using a self-developed finite-element routine, more accurate and practical calculation results for the temperature field coupled with stress, displacement and strain fields are obtained; the results match predictions and tests undertaken by earlier researchers. Our results support the reliability of our routine for calculating interdependent physical quantities of frozen soil and for describing the relationships between them. Our program can offer necessary constraints for engineering design and construction in permafrost regions.

关键词： frozen soil microcosmic mechanics roadbed coupling stress field