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1Inhibiting effect of antisense oligonucleotides phosphorthioate on gene expression of TIMP-1 in rat liver fibrosis显示文摘AIM To observe the inhibition of antisenseoligonucleotides (asON) phosphorthioate to thetissue inhibitors metalloproteinase-1 (TIMP-1)gene and protein expression in the liver tissue ofimmunologically induced hepatic fibrosis rats.The possibility of reversing hepatic fibrosisthrough gene therapy was observed.METHODS Human serum albumin (HSA) wasused to attack rats, as hepatic fibrosis model, inwhich asONs were used to block the gene andprotein expressing TIMP-1. According to theanalysis of modulator, structure protein, codingseries of TIMP-1 genome, we designed fourdifferent asONs. These asONs were injected intothe hepatic fibrosis models through coccygealvein. The results was observed by RT-PCR formeasuring TIMP-1 mRNA expression,immunohistochemistry and in situ hybridizationfor collagen Ⅰ, Ⅲ, special staining of collagenfiber, and electron microscopic examination.RESULTS Hepatic fibrosis could last within 363days in our modified model. The expressinglevel of TIMP-1 was high during hepatic fibrosisprocess. It has been proved by theimmunohistochemical and the electronmicroscopic examination that the asONphosphorthioate of TIMP-1 could exactly expressin vivo. The effect of colchicine wasdemonstrated to inhibit the expressing level ofmRNA and the content of collagen Ⅰ, Ⅲ in theliver of experimental hepatic fibrosis rats.However, the electron microscopy research andthe pathologic grading of hepatic fibrosisshowed that there was no significant differencebetween the treatment group and the modelgroup (P>0.05).CONCLUSION The experimental rat model ofhepatic fibrosis is one of the preferable modelsto estimate the curative effect of anti-hepaticfibrosis drugs. The asON phosphorthioate ofTIMP-1 could block the gene and proteinexpression of TIMP-1 in the liver of experimentalhepatic fibrosis rats at the mRNA level. It ispossible to reverse hepatic fibrosis, and it isexpected to study a new drug of anti-hepaticfibrosis on the genetic level. Colchicine has verylimited therapeutic effect on hepatic fibrosis,furthermore, its toxicity and side effects areobvious.Qing He Nie Yong Qian Cheng Yu Mei Xie Yong Xing Zhou Yi Zhan Cao The Center of Infectious Disease Diagnosis and Treatment of PLA,Tangdu Hospital,Forth Military Medical University,Xi’an 710038,Shaanxi Province,ChinaDr,Qing He Nie graduated from Qinghai Medical College as a doctor in 1983,got master degree at Beijing 302 Army Hospital in 1993,got doctor degree at the Third Military Medical University in 1998,engaged in postdoctoral research at the Fourth Military Medical University from 1998 to 2000,now an associate professor,specialized in clinical and experimental research of infectious diseases,had more than 90 papers published,coauthor of ten books,first author of one book. 2001World Journal of Gastroenterology2001,7,3:73
2Mianlüe tectonic zone and Mianlüe suture zone on southern margin of Qinling-Dabie orogenic belt显示文摘The Mianle tectonic zone (Mianle zone), an ancient suture zone in addition to the Shangdan suture in the Qinling-Dabie orogenic belt, marks an important tectonic division geo-logically separating north from south and connecting east with west in China continent. To de-termine present structural geometry and kinematics in the Mianle tectonic zone and to recon-struct the formation and evolution history involving plate subduction and collision in the Qinling-Dabie orogenic belt, through a multidisciplinary study, are significant for exploring the mountain-building orogenesis of the central orogenic system and the entire process of the major Chinese continental amalgamation during the Indosinian.ZHANG Guowei1, DONG Yunpeng1, LAI Shaocong1, GUO Anlin1, MENG Qingren2, LIU Shaofeng3, CHENG Shunyou1, YAO Anping1, ZHANG Zongqing4, PEI Xianzhi5 & LI Sanzhong6 1. Department of Geology, Northwest University, Xian 710069, China 2. Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100101, China 3. Earth Science and Resource Faculty, China University of Geosciences, Beijing 100083, China 4. Institute of Geology, Chinese Academy of Geological Sciences, Beijing 100037, China 5. Changan University, Xian 710054, China 6. Qingdao University of Oceanography, Qingdao 266003, China 2004Science China Earth Sciences2004,47,4:57
3Draining Tangjiashan Barrier Lake after Wenchuan Earthquake and the flood propagation after the dam break显示文摘Tangjiashan Barrier Lake is one of the largest barrier lakes caused by the Wenchuan Earthquake. Its risk analysis, emergency plan and effect of the emergency plan are introduced in this paper. The dam height of Tangjiashan Barrier Dam is about 105 m, and the reservoir storage capacity is 3.2×108 m3. When the dam broke the flood peak were estimated to be larger than 48000 m3/s, which might cause a enormous disaster to the downstream cities and residents. A discharge channel with 13 m deep and 8 m wide was drug, so that the water may flow out of the lake before the dam breaks. As a result, the drainage and risk mitigation project are successful. During the drainage process, the flood peak was about 6500 m3/s, and about 1.6×108 m3 of water was drained off and the residual reservoir capacity was only 8.97×107 m3. A new channel with average width 100 m was formed, which can bear floods of 200 years frequency. The successful experience and the collected data can be used to deal with the similar natural disasters in future.LIU Ning1, ZHANG JianXin2, LIN Wei3, CHENG WuYI4 & CHEN ZuYu5 1 Ministry of Water Resources of the People’s Republic of China, Beijing 100053, China 2 Bureau of Hydrology of the Ministry of Water Resources of the People’s Republic of China, Beijing 100053, China 3 Sichuan Hydrographic and Water Resources Survey Bureau Chengdu 610031, China 4 HydroChina Chengdu Engineering Corporation, Chengdu 610072, China 5 China Institute of Water Resources and Hydropower Research, Beijing 100044, China 2009Science China(Technological Sciences)2009,52,4:29
4Edge Effect Correction in the S-A Method for Geochemical Anomaly Separation显示文摘Anomaly separation using geochemical data often involves operations in the frequency domain, such as filtering and reducing noise/signal ratios. Unfortunately, the abrupt edge truncation of an image along edges and holes (with missing data) often causes frequency distribution distortion in the frequency domain. For example, bright strips are commonly seen in frequency distribution when using a Fourier transform. Such edge effect distortion may affect information extraction results; sometimes severely, depending on the edge abruptness of the image. Traditionally, edge effects are reduced by smoothing the image boundary prior to applying a Fourier transform. Zero-padding is one of the most commonly used smoothing methods. This simple method can reduce the edge effect to some degree but still distorts the image in some cases. Moreover, due to the complexity of geoscience images, which can include irregular shapes and holes with missing data, zero-padding does not always give satisfactory results. This paper proposes the use of decay functions to handle edge effects when extracting information from geoscience images. As an application, this method has been used in a newly developed multifractal method (S-A) for separating geochemical anomalies from background patterns. A geochemical dataset chosen from a mineral district in Nova Scotia, Canada was used to validate the method.Ge Yong Department of Earth and Atmospheric Science, York University, Toronto, ON, M3J 1P3, Canada State Key Laboratory of Resources and Environmental Information System, Institute of Geographic Sciences & Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China Cheng Qiuming Department of Earth and Atmospheric Science, York University, Toronto, ON, M3J 1P3, Canada Earth Systems and Mineral Resource Engineering Lab, China University of Geosciences, Wuhan 430074, China Zhang Shenyuan Department of Earth and Atmospheric Science, York University, Toronto, ON, M3J 1P3, Canada Department of Resource and Earth Science, China University of Mining & Technology, Beijing 100083, China 2004Journal of China University of Geosciences2004,15,4:28
5Numerical simulation of air-water two-phase flow over stepped spillways显示文摘Stepped spillways for significant energy dissipation along the chute have gained interest and popularity among researchers and dam engineers. Due to the com- plexity of air-water two-phase flow over stepped spillways, the finite volume computational fluid dynamics module of the FLUENT software was used to simulate the main characteristics of the flow. Adopting the RNG k-ε turbulence model, the mixture flow model for air-water two-phase flow was used to simulate the flow field over stepped spillway with the PISO arithmetic technique. The numerical result successfully reproduced the complex flow over a stepped spillway of an experiment case, including the interaction between entrained air bubbles and cavity recirculation in the skimming flow regime, velocity distribution and the pressure profiles on the step surface as well. The result is helpful for under-standing the detailed information about energy dissipation over stepped spillways.CHENG Xiangju1, CHEN Yongcan1 & LUO Lin2 1. Department of Hydraulic Engineering, Tsinghua University, Beijing 100084, China 2. State Key Laboratory of Hydraulics and Mountain River Engineering, Sichuan University, Chengdu 610065, China 2006Science China(Technological Sciences)2006,49,6:23
6Preparation of human single chain Fv antibody against hepatitis C virus E2 protein and its identification in immunohistochemistry显示文摘AIM: To screen human single chain Fv antibody (scFv)against hepatitis C virus E2 antigen and identify its applicationin immunohistochemistry.METHODS: The phage antibody library was panned by HCVE2 antigen, which was coated in microtiter plate. After fiverounds of biopanning,56 phage clones were identified specificto HCV E2 antigen. The selected scFv clones were digestedby SfiI/NotI and DNA was sequenced. Then it was subclonedinto the vector pCANTABSE for expression as E-taggedsoluble scFv. The liver tissue sections from normal personand patients with chronic hepatitis B and chronic hepatitis Cwere immunostained with HCV E2 scFv antibody.RESULTS: The data of scFv-E2 DNA digestion and DNAsequencing showed that the scFv gene is composed of 750bp. ELISA and immunohistochemistry demonstrated that thehuman single chain Fy antibody against hepatitis C E2 antigenhas a specific binding character with hepatitis virus E2 antigenand paraffin-embedded tissue, but did not react with liver tissuesfrom healthy persons or patients with chronic hepatitis B.CONCLUSION: We have successfully screened andidentified HCV E2 scFv and the scFv could be used in theimmunostaining of liver tissue sections from patients withchronic hepatitis C.Yan-Wei Zhong Jun Cheng Gang Wang Shuang-Shuang Shi Li Li Ling-Xia Zhang Ju-Mei Chen Gene Therapy Research Center,Institute of Infectious Diseases,302 Hospital of PLA,26 Fengtai Road,Beijing 100039,China 2002World Journal of Gastroenterology2002,8,5:21
7The precipitation strengthening behavior of Cu-rich phase in Nb contained advanced Fe-Cr-Ni type austenitic heat resistant steel for USC power plant applicationCheng-yu Chi a, Hong-yao Yu b, Jian-xin Dong b, Wen-qing Liu c, Shi-chang Cheng d, Zheng-dong Liu d, Xi-shan Xie b a School of Metallurgical and Ecological Engineering, University of Science & Technology Beijing, Beijing 100083, China b School of Materials Science and Engineering, University of Science & Technology Beijing, Beijing 100083, China c Instrumental Analysis & Research Center, Shanghai University, Shanghai 200444, China d Central Iron and Steel Research Institute, Beijing 100081, China 2012Progress in Natural Science:Materials International2012,22,3:20
8TRAF-mediated regulation of immune and inflammatory responses显示文摘The tumor necrosis factor (TNF) receptor-associated factor (TRAF) family consists of six mammalian members,and is shown to participate in signal transduction of a large number of receptor families including TNF receptor family (TNFR) and Toll-like receptors-interleukin-1 receptors (TLR-IL-1R) family.Upon receptor activation,TRAFs are directly or indirectly recruited to the intracellular domains of these receptors.They subsequently engage other signaling proteins to activate inhibitor of κB kinase (IKK) complex,TRAF family member-associated NF-κB activator (TANK)-binding kinase 1 (TBK1) and inducible I κB kinase (IKK-i) (also known as IKKε),ultimately leading to activation of transcription factors such as NF-κB and interferon-regulatory factor (IRF) to induce immune and inflammatory responses.WANG YaYa1,ZHANG Peng2,LIU YingFang2 & CHENG GenHong1 1 Department of Microbiology,Immunology & Molecular Genetics,University of California Los Angeles,609 Charles E.Young Drive East,Los Angeles,California 90095,USA 2 National Laboratory of Biomacromolecules,Institute of Biophysics,Chinese Academy of Sciences,Beijing 100101,China 2010Science China(Life Sciences)2010,53,2:19
9WATER POLLUTION IN THE RIVER MOUTHS AROUND BOHAI BAY显示文摘Twelve water samples were collected and analyzed. The samples were taken from the river mouths around Bohai Bay including the Jiyun, New Yongding, Haihe, Dagu, Duliujian, Qingjinghuang, Qikou, Dakou, and Yellow Rivers, and tested for concentrations of heavy metals, arsenic, total nitrogen (TN) and total phosphorus (TP). The results show that the river mouths are polluted and the water quality exceeds Class V of the Environmental Quality Standard for Surface Water (EQSSW). The main pollutants are Hg, nitrogen (N) and phosphorus (P). The concentrations of the other pollutants are within Class Ⅱ of the Standard. The Hg content in the Haihe River mouth is now 10 times higher than it was 20 years ago, indicating that the accelerating water pollution has reached an alarming level. The high concentrations of N and P cause eutrophication of the waters.Analysis indicates that the terrestrial pollutants and nutrients are the main cause of frequently occurring red tides in the Bohai Sea.Cheng LIU, Zhao-Yin WANG and Yun HE Dr., Asso. Prof., International Research and Training Center on Erosion and Sedimentation, Beijing 100044.China,Prof.. Dept. of Hydraulic Engineering, Tsinghua University & International Research and Training Center onErosion and Sedimentation, Beijing, 100084, China.China Institute of Water Resources and Hydropower Research. Beijing 100084, China, 2003International Journal of Sediment Research2003,18,4:18
10Mycoplasma infections and different human carcinomas显示文摘AIM To explore relationships between human carcinomas and mycoplasma infection.METHODS Monoclonal antibody PD4, which specifically recognizes a distinct protein from mycoplasma hyorhinis, was used to detect mycoplasma infection in different paraffinembedded carcinoma tissues with immunohistochemistry. PCR was applied to amplify the mycoplasma DNA from the positive samples for confirming immunohistochemistry.RESULTS Fifty of 90 cases (56%) of gastric carcinoma were positive for mycoplasma hyorhinis. In other gastric diseases, the mycoplasma infection ratio was 28% (18/49) in chronic superficial gastritis, 30% (14/ 46) in gastric ulcer and 37% (18/ 49) in intestinal metaplasia. The difference is significant with gastric cancer (X2=12.06, P<0.05). In colon carcinoma, the mycoplasma infection ratio was 55.1% (32/58), but it was 20.9% (10/49) in adenomarous polyp (X2=13.46, P<0.005).Gastric and colon cancers with high differentiation had a higher mycoplasma infection ratio than those with low differentiation (P< 0.05). Mycoplasma infection in esophageal cancer, lung cancer, breast cancer and glioma was 50.9% (27/53), 52.6% (31/ 59), 39.7%(25/63) and 41% (38/91), respectively. The mycoplasma DNA was successfully amplified with the DNA extracted from the cancer tissues that were positive for mycoplasma infection (detected with antibody PD4).CONCLUSION There was high correlation between mycoplasma infection and different cancers, which suggests the possibility of an association between the two. The mechanism involved in oncogenesis by mycoplasma remains unknown.Su Huang Ji You Li Jan Wu Lin Meng Cheng Chao Shou Beijing Institute for Cancer Research, Peking University School of Oncology, Beijing 100034. ChinaSu Huang, received B. A from Jiangxi Medical College of China in 1994. Now she is a graduate student pursuing a Ph. D degree at the Peking University School of Oncology. 2001World Journal of Gastroenterology2001,7,2:18
11ON THE STRICT EFFICIENCY IN A LOCALLYCONVEX SPACE显示文摘In this paper, a new concept, strictly efficient points in locally convex spaces,is introduced, and scalar characterization of a strictly efficient point is established. Furthermore, we study the best approximation property for a strictly efficient point by an equivalent norm.FU Wantao (Department of Mathematics, Nanchang University, Nanchang 330047, China)CHENG Yonghong (Institute of Systems Science, Acadetnia Sinica, Beijing 100080, China) 1999Systems Science and Mathematical Sciences1999,12,1:17
12Expression of VEGF_(121)in gastric carcinoma MGC803 cell line显示文摘INTRODUCTIONVascular endothelial growth factor(VEGF)whichis also known as vascular permeability factor(VPF)is a heparin-binding,dimeric polypeptide growthfactor and a potent mitogen for endothelial cells.VEGF can stimulate the endothelial cell growth andenhance the motility through its two knownreceptors flt-1 and KDR.Acting through thesereceptors,VEGF may stimulate angiogenesisXue Jun Tian Jian Wu Lin Meng Zhi Wei Dang Cheng Chao Shou Beijing Institute for Cancer Research,Oncology School of Beijing Medical University,Beijing 100034,China Institute of Cancer Research,Chinese Academy of Medical Sciences,Beijing 100021,China 2000World Journal of Gastroenterology2000,6,2:17
13Colonoscopic screening and follow-up for coiorectal cancer in the elderly显示文摘AIM: To improve the prevention and treatment of senilepatients with colorectal cancer by evaluating the importanceof colonoscopy in clinical screening and follow-up.METHODS: Clinical screening of colonoscopy wasperformed for 2196 patients aged 60-90 years old accordingto the protocol,and 174lO of them (79.2 %) were followed-up.RESULTS: Colorsctal cancer was found in 52 patients, and the detectable rate was 2. 4 %. Among them, 19 werediagnosed as early colorectsl cancer, accounting for 36. 5 %of the detected colorectal cancer. Among the followed-uppatients, early colorectsl cancer was found in 9, accountingfor 45.0 % of the detected colorsctal cancer. The resectsblerate and 5 years survival rate of colorectsl cancer were 97.7% and 80.9 % respectively. The incidence of complicationwas 0.05 %, and the successful rate of cecum intubationwas 98.9 %.CONCLUSION: Colonuscopic screening and follow-up of theelderly for colorectsl cancer and pre-cancerous lesion(adenomatoid polyp) can increase the detectable rate ofearly colorectal cancer and improve its prevention andtreatment.Jun Wan Zi-Qi Zhang Cheng Zhu Meng-Wei Wang Dong-Hai Zhao Yong-He Fu Jian-Ping Zhang Ya-Hong Wang Ben-Yan Wu,Department of Gastroenterology,General Hospital of the Chinese PLA,Beijing 100853,China 2002World Journal of Gastroenterology2002,8,2:14
14APPLICATION OF SWAT MODEL IN THE UPSTREAM WATERSHED OF THE LUOHE RIVER显示文摘In the Huanghe (Yellow) River basin,soil erosion is a serious problem,while runoff and sediment yield simulation has not been extensively studied on the basis of GIS (Geographic Information System) and distributed hydrological model. GIS-based SWAT (Soil and Water Assessment Tool) model was used to simulate runoff and sediment in the Huanghe River basin. The objective of this paper is to examine the applicability of SWAT model in a large river basin with high sediment runoff modulus,which could reach 770t/(km2·a). A two-stage 'Brute Force' optimization procedure was used to calibrate the parameters with the observed monthly flow and sediment data from 1992 to 1997,and with input parameters set during the calibration process without any change the model was validated with 1998-1999’s observed data. Coefficient of examination (R2) and Nash-Suttcliffe simulation efficiency (Ens) were used to evaluate model prediction. The evaluation coefficients for simulated flow and sediment,and observed flow and sediment were all above 0.7,which shows that SWAT model could be a useful tool for water resources and soil conservation planning in the Huanghe River basin.ZHANG Xue-song, HAO Fang-hua, CHENG Hong-guang, LI Dao-feng (State Key Laboratory of Water Environment Simulation,Institute of Environmental Sciences, Beijing Normal University,Beijing 100875,P. R. China) 2003Chinese Geographical Science2003,13,4:14
15Power system low frequency oscillation monitoring and analysis based on multi-signal online identification显示文摘The advance in the wide-area measurement system (WAMS) is driving the power system to the trend of wide-area monitoring and control.The Prony method is usually used for low frequency oscillation online identification.However,the identified amplitude and phase information is not sufficiently used.In this paper,the amplitude is adopted to detect the occurrence of the oscillation and to obtain the mode observability of the sites.The phase is adopted to identify the oscillation generator grouping and to obtain the mode shapes.The time varying characteristics of low frequency oscillations are studied.The behaviors and the characters of low frequency oscillations are displayed by dynamic visual techniques.Demonstrations on the '11.9' low frequency oscillation of the Guizhou Power Grid substantiate the feasibility and the validation of the proposed methods.YUAN Ye1,2,SUN YuanZhang2,CHENG Lin2,CHEN Gang2 & WANG Peng3 1 State Nuclear Electric Power Planning Design and Research Institute,Beijing 100032,China 2 State Key Laboratory of Power Systems,Deptment of Electrical Engineering,Tsinghua University,Beijing 100084,China 3 EEE School,Nanyang Technological University,Singapore 2010Science China(Technological Sciences)2010,53,9:13
16Lithospheric seismic fabrics of Sulu ultrahigh-pressure metamorphic belt显示文摘Calibration of seismic reflectors appearing in the crust of the Chinese continent sci- entific drilling site can be completed through the correlation studies between direct evidences, such as the drill cores, and geophysical signatures; therefore the interpretation of geophysical data could produce reliable results of crustal structure and composition. On the other hand, there are two Cenozoic volcanoes close to the scientific drilling site; analyzing composition of xenoliths existent in the volcanoes and evaluating their seismic velocities can also offer information about the mantle and lower crust. After the calibration via cores and well-logging data, the seismic re- flectors appearing in the UHP belt can be caused by lithological changes within the UHP rock slice, ductile shearing rock-suites, and later fracture zones. Among these sources, ductile shearing resulted in displacement and detachment of original rock-sheets, producing some rock-interbeds of several hundred meters thick that are named the ductile shearing rock-suites. A suite consists of mylonized gneiss and eclogite slices that underwent shearing, becoming the major mechanism responsible to generate regional strong reflections. The UHP rock-slice is characterized by complicated structures and high density, high seismic velocity and high electri- cal resistivity, its thickness is usually less than 11 km. Velocity and density of the gneiss-layer beneath gradually tend to normal with increasing depth. Based on the xenoliths we can infer that the middle crust contains a lot of gneisses, and the lower crust consists of different granulites. The lithospheric mantle has multi-layer structures and consists mainly of spinal lherzolite and harzburgite, implying late Mesozoic lithospheric thinning. The seismic fabrics with different ori- gins were possible products of different geodynamic processes. For instance, the UHP rock-slice was produced by the UHP metamorphic process and the exhumation of subducted supercrustal rocks after the Triassic collision between the Yangtze and Sino-Korean cratons; whilst the ductile shearing rock-suites resulted from shearing deformation processes during the subduction and exhumation. The normal velocity below the UHP rock-slice was correlated with Mesozoic exten- sion processes in the area. Through careful calibration of seismic reflectors and analyzing xeno- liths, one can find the relationship between the causes of seismic reflectors and corresponding geodynamic processes, offering a new basis for reconstruction of regional dynamic evolution history.YANG Wencai 1 , YANG Wuyang 1 , JIN Zhenmin 2 & CHENG Zhenyan 1 1. Institute of Geology, Chinese Academy of Geological Sciences, Beijing 100037, China 2. China University of Geosciences, Wuhan 430074, China 2005Science China Earth Sciences2005,48,5:13
17Satellite SAR interferometric observations of displacements associated with urban subsidence in Suzhou, Eastern China显示文摘SAR interferometry (InSAR) has a high potential for surface displacement mapping in the range from millimeter to meter. In this paper the potential of ERS-1/2 SAR interferometry for mapping subtle land subsidence has been investigated. A time series of ERS-1/2 SAR data from February 1993 to February 2000 is collected from measurements taken in Suzhou city, Jiangsu Province, China, eight ERS-1/2 SAR images are used to create seven interferograms, and three differential interferograms are produced using the three-pass method, which clearly show the spatial extent of land subsidence. The deformation maps are validated by leveling surveys, the correlation coefficient and standard deviation between them are 0.943 and 0.1706 respectively. Based on seven benchmarks, the subsidence rates are estimated, the overall trends are in close agreement with InSAR results. The results of study show that for the mapping of land subsidence in urban environments InSAR has a strong potential due to its cost-saving, high resolution and accuracy.WANG Chao, ZHANG Hong, LIU Zhi, CHENG Suozhong and LU Guonian(1. LARSIS, Institute of Remote Sensing Applications, Chinese Academy of Sciences, Beijing 100101, China 2. Department of Geography, Nanjing Normal University, Nanjing 210097, China) 2002Progress in Natural Science:Materials International2002,12,10:13
18Research progress on electrical signals in higher plants显示文摘This review introduces the characteristics of electrical signals in higher plants and their corresponding physiological significance, and describes in detail the impact of environmental factors (e.g. light and temperature) on the electrical potential of the plants. Also, we evaluate the measurement techniques used for electrical signals in plants, including intracellular measurement, extracellular measurement, measurement of the ion channel based on the patch-clamp technique and on the non-invasive microelectrode vibrating probe technique. We also give a brief review of the applications of these methods for investigating electrical signals in plants. The ionic mechanism of electrical activity in plants is then discussed in terms of environmental response in higher plants, and this is used to provide a theoretical basis for quantitative description of the electrical signals in plants. A model for interpretation of the electrical signal mechanisms in higher plants is discussed, but further experiments are required for the verification of this model.Xiaofei Yana, Zhongyi Wang a, Lan Huang a, Cheng Wang b, Ruifeng Hou b, Zhilong Xu b, Xiaojun Qiao b a College of Information and Electrical Engineering, China Agricultural University, Beijing 100083, China b National Engineering Research Center for Information Technology in Agriculture, Beijing 100097, China 2009Progress in Natural Science:Materials International2009,19,5:13
19KINETICS OF REACTION BETWEEN PbS AND PbO显示文摘The rate equation of reaction between PbS and PbO is dα/dt=kxPbS3 xPbO-2.A transition product,PbSO4·2PbO,is found by X-ray diffraction analysis.The reaction mechanism was dis-cussed on the basis of electron transfer.LI Cheng Beijing Central Design and Research Institute for Non-Ferrous Metallurgical Industry,Beijing,ChinaLIU Chunpeng,Kunming Institute of Technology,Kunming,China LI Cheng,Metallurgical Dept.No.l,Beijing Central Design and Research Institute for Non-Ferrous Metallurgical Industry,Beijing 100038,China 1990Acta Metallurgica Sinica(English Letters)1990,3,11:12
20Restudies on Body Surface of Dung Beetle and Application of Its Bionics Flexible Technique显示文摘A scanning electron microscope was used to observe the structures of the setae on the surface of a dung beetle Copris ochus, Motschulsky. There are lots of setae on the body surface, especially on the ventral part surface and lateral to the legs which are different in size, arrangement and shape. These setae have different lengths and many thorns on the whole seta. The top ends of these setae stand up without furcations which direct uprightly towards the surface of the touched soil. By the method of removing these setae, getting the insect weight before and after digging into the dung we affirm farther that the setae on the beetle body surface form the anti-stick and non-adherent gentle interface. The soil machines and components made by imitating the gentle body surface of beetles have favorable non-adherent results.Jiurong Sun 1, Jianqiao Li 2, Hong Cheng 1, Zhendong Dai 3, Luquan Ren 2 1.College of Life Sciences, Peking University, Beijing, 100871,P.R. China 2.Key Laboratory of Terrain-Machine Bionics Engineering (Ministry of Education,China), Jilin University at Nanling Campus, Changchun, 130022,P.R.China 3.College of Mechanical and Electrical Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing, 210016,P.R.China 2004Journal of Bionic Engineering2004,1,1:12
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