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1A complete sequence and comparative analysis of a SARS-associated virus(Isolate BJ01)显示文摘The genome sequence of the Severe Acute Respiratory Syndrome (SARS)-associated virus provides essential information for the identification of pathogen(s), exploration of etiology and evolution, interpretation of transmission and pathogenesis, development of diagnostics, prevention by future vaccination, and treatment by developing new drugs. We report the complete genome sequence and comparative analysis of an isolate (BJ01) of the coronavirus that has been recognized as a pathogen for SARS. The genome is 29725 nt in size and has 11 ORFs (Open Reading Frames). It is composed of a stable region encoding an RNA-dependent RNA polymerase (composed of 2 ORFs) and a variable region representing 4 CDSs (coding sequences) for viral structural genes (the S, E, M, N proteins) and 5 PUPs (putative uncharacterized proteins). Its gene order is identical to that of other known coronaviruses. The sequence alignment with all known RNA viruses places this virus as a member in the family of Coronaviridae. Thirty putative substitutions have been identified by comparative analysis of the 5 SARS- associated virus genome sequences in GenBank. Fifteen of them lead to possible amino acid changes (non-synonymous mutations) in the proteins. Three amino acid changes, with predicted alteration of physical and chemical features, have been detected in the S protein that is postulated to beinvolved in the immunoreactions between the virus and its host. Two amino acid changes have been detected in the Mprotein, which could be related to viral envelope formation. Phylogenetic analysis suggests the possibility of non-human origin of the SARS-associated viruses but provides noevidence that they are man-made. Further efforts should focus on identifying the etiology of the SARS-associated virus and ruling out conclusively the existence of otherpossible SARS-related pathogen(s).QIN E'de ZHU Qingyu YU Man FAN Baochang CHANG Guohui SI Bingyin YANG Bao PENG Wenming JIANG Tao LIU Bohua DENG Yongqiang LIU Hong ZHANG Yu WANG Cui LI Yuquan GAN Yonghua LI Xiaoyu L Fushuang TAN Gang CAO Wuchun, YANG Ruifu Institute of Microbiology and Epidemiology, Chinese Academy of Military Medical Sciences, Beijing 100071, China WANG Jian, LI Wei, XU Zuyuan, LI Yan, WU Qingfa, LIN Wei, CHEN Weijun, TANG Lin, DENG Yajun, HAN Yujun, LI Changfeng, LEI Meng, LI Guoqing, LI Wenjie, L Hong, SHI Jianping, TONG Zongzhong, ZHANG Feng, LI Songgang, LIU Bin, LIU Siqi, DONG Wei, WANG Jun, Gane K-S Wong, YU Jun & YANG Huanming* Beijing Genomics Institute, Chinese Academy of Sciences, Beijing 101300 National Center for Genome Information, Beijing 101300, China 2003Chinese Science Bulletin2003,48,10:121
2SHRIMP zircon U-Pb geochronology of early Mesozoic felsic igneous rocks from the southern Lancangjiang and its tectonic implications显示文摘The SHRIMP zircon U-Pb geochronology of three typical samples, including two monzo nitic granites from the Lincang batholith and a rhyolite from the Manghuai Formation are presented in the southern Lancangjiang, western Yunnan Province. The analyses of zircons for the biotite monzonitic granites from the northern (02DX-137) and southern (20JH-10) Lincang batholith show the single and tight clusters on the concordia, and yield the weighted mean 206Pb/238U ages of 229.4 ± 3.0 Ma and 230.4 ± 3.6 Ma, respectively, representing the crystallized ages of these granites. The zircons for the rhyolitic sample (02DX-95) from the Manghuai Formation give a weighted mean 206Pb/238U age of 231.0 ± 5.0 Ma. These data suggest that the igneous rocks from the Lincang granitic batholith and Manghuai Formation have a similar crystallized age. In combination with other data, it is inferred that both were generated at a narrow age span (~230 Ma) and were originated from the postcollisional tectonic regime. An early Proterozoic 206Pb/238U apparent age of 1977±44 Ma is additionally obtained from one zircon from the biotite monzonitic granite (southern Lincang batholith), indicative of devel- opment of the early Proterozoic Yangtze basement in the region. These precisely geochronological data provide important constraints on better understanding the Paleozoic tectonic evolution of the Tethys, western Yunnan Province.PENG Touping1,2, WANG Yuejun1, FAN Weiming1, LIU Dunyi3, SHI Yuruo3 & MIAO Laicheng4 1. Key Laboratory of Isotope Geochronology and Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China 2. Graduate University of Chinese Academy of Sciences, Beijing 100039, China 3. SHRIMP isotope Laboratory, Chinese Academy of Geological Sciences, Beijing 100037, China 4. Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029, China 2006Science China Earth Sciences2006,49,10:55
3Seismic Sequence in Carbonate Rocks By Vibrational Liquefaction显示文摘On the basis of the records of strong seismic events taking place in soft carbonate sediments, a new seismic sequence system of vibrational liquefaction is established, which consists of a series of units, such as escaped structure of micrite veins and liquefied deformation formed in the period of seismic liquefaction, land subsidence structure after liquefaction, tsunamic hummocky and turbidite produced by seismic events, This sequence is a generalization and summation of field observation in vast areas, which shows the whole process of a strong seismic event and provides an unified theoretical explanation. The pattern of the seismic sequence by vibrational liquefaction provides one of correlation standards for geologists in the field to discriminate events in carbonate sequences. Based on the pattern of seismic sequence, the authors first advance a new conception of the Palaeo-Tanlu (Tancheng-Lujiang) Zone and discuss primarily its geological significations.Qiao Xiufu, Song Tianrui, Gao Linzhi, Peng Yang, Li Haibing, Gao Mai, Song Biao and Zhang QiaodaInstitute of Geology, Chinese Academy of Geological Sciences, Beijing 1994Acta Geologica Sinica(English Edition)1994,68,3:39
4Changes of plasma D(-) -lactate, diamine oxidase and endotoxin in patients with liver cirrhosis显示文摘BACKGROUND: Plasma D(-)-lactate and diamine oxidase (DAO) can reflect patients’ intestinal mucosal condition. We evaluated the changes of plasma D (-)-lactate, DAO and endotoxin activities and their significance in patients with liver cirrhosis. METHODS: Fifty liver cirrhosis patients were enrolled into experimental group and 30 healthy people into control group. The plasma levels of D(-)-lactate, DAO and endo- toxin were detected spectrophotographically. RESULTS: The level of D(-)-lactate was significantly high- er in the experimental group than that in the control group (P<0.01). Significant differences of D (-)-lactate levels were observed in Child-Pugh subgroups of the experimen- tal group (P <0. 01). The level of DAO was significantly higher in the experimental group than that in the control group (P <0.01), but the level of DAO in Child-Pugh sub- group C was significantly lower than that in Child-Pugh subgroup B (P<0.01). The level of endotoxin was signifi- cantly increased in the experimental group except Child Pugh subgroup A (P<0.01). The plasma levels of D(-) lactate, DAO and endotoxin were positively correlated with each other (P<0.01). CONCLUSIONS: The data suggest that both plasma D(-) lactate and DAO activity are sensitive markers for early diagnosis of gut failure and endotoxemia in patients with liver cirrhosis. The impairment of intestinal barrier func- tion may be one of the critical reasons for deterioration of liver cirrhosis.Peng Ruan, Zuo-Jiong Gong and Quan-Rong Zhang Wuhan, China Department of Infectious Diseases, Renmin Hospital Wuhan University Medical College, Wuhan 430060 , China 2004Hepatobiliary & Pancreatic Diseases International2004,3,1:31
5Numerical simulation of mechanisms of deformation,failure and energy dissipation in porous rock media subjected to wave stresses显示文摘The pore characteristics,mineral compositions,physical and mechanical properties of the subarkose sandstones were acquired by means of CT scan,X-ray diffraction and physical tests.A few physical models possessing the same pore characteristics and matrix properties but different porosities compared to the natural sandstones were developed.The 3D finite element models of the rock media with varied porosities were established based on the CT image processing of the physical models and the MIMICS software platform.The failure processes of the porous rock media loaded by the split Hopkinson pressure bar(SHPB) were simulated by satisfying the elastic wave propagation theory.The dynamic responses,stress transition,deformation and failure mechanisms of the porous rock media subjected to the wave stresses were analyzed.It is shown that an explicit and quantitative analysis of the stress,strain and deformation and failure mechanisms of porous rocks under the wave stresses can be achieved by using the developed 3D finite element models.With applied wave stresses of certain amplitude and velocity,no evident pore deformation was observed for the rock media with a porosity less than 15%.The deformation is dominantly the combination of microplasticity(shear strain),cracking(tensile strain) of matrix and coalescence of the cracked regions around pores.Shear stresses lead to microplasticity,while tensile stresses result in cracking of the matrix.Cracking and coalescence of the matrix elements in the neighborhood of pores resulted from the high transverse tensile stress or tensile strain which exceeded the threshold values.The simulation results of stress wave propagation,deformation and failure mechanisms and energy dissipation in porous rock media were in good agreement with the physical tests.The present study provides a reference for analyzing the intrinsic mechanisms of the complex dynamic response,stress transit mode,deformation and failure mechanisms and the disaster mechanisms of rock media.JU Yang1,2,WANG HuiJie1,YANG YongMing1,HU QinAng3 & PENG RuiDong1 1 State Key Laboratory of Coal Resources and Safe Mining,Beijing Key Laboratory of Fracture and Damage Mechanics of Rock and Concrete,China University of Mining and Technology,Beijing 100083,China 2 Department of Mechanical and Manufacturing Engineering,University of Calgary,Calgary,Alberta,T2N 1N4,Canada 3 School of Environment and Civil Engineering,College of Engineering,Oklahoma State University,Stillwater,OK 74078,USA 2010Science China(Technological Sciences)2010,53,4:32
6Detection of T lymphocyte subsets and mIL-2R on surface of PBMC in patients with hepatitis B显示文摘AIM: To study the levels of T lymphocyte subsets andmembrane interleukin-2 receptor (mIL-2R) on surface ofperipheral blood mononuclear cells (PBMCs) of patients withhepatitis B and its role in the pathogenesis of hepatitis B.METHODS: The levels of T lymphocyte subsets and mIL-2R in PBMC before and after being stimulated with PHAwere detected by biotin-streptavidin (BSA) technique in 196cases of hepatitis B.RESULTS: In patients with hepatitis B, the levels of CD3+,CD4+ cells, and the ratio of CD4+ cells/CD8+ cells were lower,but the level of CD8+ cells was higher than those in normalcontrols (42.20±6.01 vs65.96±6.54, 38.17±5.93 vs41.73±6.40,0.91±0.28 vs 1.44±0.31, 39.86±6.36 vs30.02±-4.54, P<0.01).The total expression level of mIL-2R in PBMC before andafter being stimulated with PHA was also lower than thosein normal controls (3.47±1.55 vs4.52±1.49, 34.03±2.94 vs37.95±3.00, P<0.01). In all the patients with hepatitis B, thelevels of T lymphocyte subsets and mIL-2R in PBMC withHBV-DNA (+) were lower than those with HBV-DNA (-),which were significantly different (39.57±7.11 vs44.36±5.43,34.36±7.16 vs 40.75±5.87, 37.82±6.54 vs 41.72±6.21,0.88±0.33 vs0.99±0.27, 2.82±1.62 vs3.85±1.47, 31.56±3.00vs35.84±2.83, P<0.01). In addition, the levels of CD3+, CD4+,CD8+ cells, the ratio of CD4+ cells/CD8+ cells and mIL-2R amongdifferent courses of hepatitis B were all significantly different(F=3 723.18, P<0.01. F=130.43, P<0.01. F=54.01, P<0.01.F=2.99, P<0.05. F=7.16, P<0.01).CONCLUSION: Both cellular and humoral immune functionsare obviously in disorder in patients with hepatitis B, whichmight be closely associated with the chronicity in patients.Ke-Xia Wang Jiang-Long Peng Xue-Feng Wang Ye Tian Jian Wang Chao-Pin Li School of Medicine,Anhui University of Science and Technology,Huainan 232001,Anhui Province,China 2003World Journal of Gastroenterology2003,9,9:32
7Energy analysis for damage and catastrophic failure of rocks显示文摘The development history and current state of studies on the characteristics and mechanisms of deformation and failure of rock materials were briefly reviewed from the viewpoint of energy.The main scope and the achievable objectives of the energy-based research system were expatiated.It was validated by experiments that the damage process of rocks can be well described by the rock damage evolution equation established based on energy dissipation.It was found from the uniaxial compression and biaxial compression tests that only a small proportion of the total input energy in hard rocks is dissipated before peak load and a large proportion in soft rocks is dissipated before peak load.For both hard and soft rocks,the energy dissipated after peak load accounts for a greater proportion.More energy would be required for rock failure under equal biaxial compression than under unequal biaxial compression.The total absorbed energy is different for rock failure under high-rate loading and low-rate loading.More fragmented failure pattern usually corresponds to higher energy absorption.The mesoscopic analysis on the damage and failure of bedded salt rocks showed that the energy dissipation is prominent and the total absorbed energy for rock failure is low when cracks propagate in the weak mud interlayer while it is contrary when cracks propagate in the salt rock.The energy accumulation,transfer,dissipation and release during the failure process of tunnel with impending failure under disturbance were analyzed theoretically based on the elastoplastic mechanics theory.Furthermore,the spatial distribution of energy dissipation and energy release of fractured rocks under unloading was simulated numerically.It was demonstrated that energy is likely to be released from the weakest surface under compression,which triggers the global failure of rocks.XIE HePing 1,2,LI LiYun 2,1,JU Yang 2,PENG RuiDong 2 & YANG YongMing 2 1 Sichuan University,Chengdu 610065,China 2 State Key Laboratory of Coal Resources and Safe Mining,Beijing Key Laboratory of Fracture and Damage Mechanics of Rock and Concrete,China University of Mining and Technology,Beijing 100083,China 2011Science China(Technological Sciences)2011,54,S1:29
8The intracellular mechanism of alpha-fetoprotein promoting the proliferation of NIH 3T3 cells显示文摘AIM The existence and properties of alpha-fetoprotein (AFP) receptor on the surface of NIH 3T3 cells and the effects of AFP on cellular signal transduction pathway were investigated. METHODS The effect of AFP on the proliferation of NIH 3T3 cells was measured by incorporation of 3H-TdR. Receptor-binding assay of 125I-AFP was performed to detect the properties of AFP receptor in NIH 3T3 cells. The influences of AFP on the [cAMP]i and the activities of protein kinase A (PKA) were determined. Western blot was used to detect the change of K-ras P21 protein expression. RESULTS The proliferation of NIH 3T3 cells treated with 0-80 mg/L of AFP was significantly enhanced. The Scatchard analysis indicated that there were two classes of binding sites with KD of 2.722×10-9M (Bmax=12810 sites per cell) and 8.931× 10-SM (Bmax=l19700 sites per cell) respectively. In the presence of AFP (20 mg/L), the content of cAMP and activities of PKA were significantly elevated . The level of K-ras P21 protein was upregulated by AFP at the concentration of 20 mg/L. The monoclonal antibody against AFP could reverse the effects of AFP on the cAMP content, PKA activity and the expression of K-ras p21 gene. CONCLUSION The effect of AFP on the cell proliferation was achieved by binding its receptor to trigger the signal transduction pathway of cAMP-PKA and alter the expression of K- ras p21 gene.MENG SEN LI, PING FENG LI, FBI YI YANG, SHI PENG HE, Guo GUANG DU, GANG LI1 Department of Biochemistry and Molecular Biology, 2 Department of Biophysics, Health Science Center, Peking University, Beijing 100083, China 2002Cell Research2002,12,2:27
9Micro-mechanical analysis of dynamic processes of nanomanipulation显示文摘In this study, atomic force microscope (AFM) tips are used as tools to cut and manipulate carbon nanotubes on various surfaces. The lateral forces acting on AFM tips during manipulation are also recorded and analyzed from the perspective of micro-mechanics. It is found that differences in surface conditions can lead to obvious increase in micro-friction between nanotube and substrate. And also due to rehybridization, carbon nanotubes present excellent resilience when undergoing different degrees of strain. Finally, carbon nanotubes can complexly deform from elastic stage to plastic stage before complete rupture.HU Jie, ZHANG Yujun, LI Peng, WANG Hui, HUANG Lan & HU YuanzhongState Key Laboratory of Tribology, Tsinghua University, Beijing 100084, China Department of Physics, Tsinghua University, Beijing 100084, China College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, China 2004Science China(Physics,Mechanics & Astronomy)2004,47,z1:28
10Prevention and Treatment of Osteoporosis with Chinese Herbal Medicines显示文摘In this paper,laboratory reports,medication rules,formulating principles,and research methods are summarized and analyzed,including single herb,compound herbs,and the problems in the prevention and treatment of osteoporosis(OP) within the past decade.With widely recognized efficacy,satisfying achievements have been achieved in preventing and treating OP with Chinese herbal medicines(CHM).However,due to the complex constituents,the pharmacological activities and mechanism of CHM are not clear yet,and there is no unified standard on the diagnosis and syndrome differentiation of OP and the efficacy evaluation of CHM in the treatment.Accordingly,the research in the future should focus on the pharmacology and standardization of CHM in treating OP.ZHAO Xiao-ling1,2,FENG Yu-xiong1,2,3,PENG Yong1,2 1.Institute of Medicinal Plant Development,Chinese Academy of Medical Sciences and Peking Union Medical College,Beijing 100193,China 2.Key Laboratory of Bioactive Substances and Resources Utilization of Chinese Herbal Medicines,Ministry of Education,Beijing 100193,China 3.College of Basic Medicine,Guangxi University of Chinese Medicine,Nanning 530001,China 2012Chinese Herbal Medicines2012,4,4:28
11Telomerase activity in gastric cancer and its clinical implications显示文摘INTRODUCTIONThedevelopmentofcarcinomaresultsfrommultipleindependentgeneticchangesthatactivateprotooncogenesorinactivatetheac...ZHAN Wen Hua, MA Jin Ping, PENG Jun Sheng, GAO Jing Song, CAI Shi Rong, WANG Jian Ping, ZHENG Zhang Qing and WANG Lei 1999World Journal of Gastroenterology1999,5,4:25
12Different Effects of Homocysteine and Oxidized Low Density Lipoprotein on Methylation Status in the Promoter Region of the Estrogen Receptor α Gene显示文摘我们调查了人的效果半胱氨酸(Hcy ) 和在雌激素受体高山的倡导者区域的 DNA methylation 上的氧化低密度脂蛋白(ox-LDL ) 哈(ERalpha ) 基因,和它在动脉粥样硬化的致病的潜在的机制。人的有教养的光滑的肌肉房间(SMC ) 被 Hcy 和 ox-LDL 为时间的不同经期与不同集中对待。DNA methylation 地位是由嵌套的 methylation 特定的聚合酶链反应的 assayed,在 SMC 和泡沫房间形成积累了的类脂化合物被检验,油红 O 染色。SMC 的增长是由 the3-(4,5-dimethylthiazol-2-yl ) 的 assayed -2,5-diphenyltetrazolium 溴化物方法。结果证明 ox-LDLin 节制导致的集中(10-40 mg/L ) 在 SMCs.However 的 ERagene 的倡导者区域的 de novo methylation, ox-LDL 的高集中(50 mg/L ) ,导致了时代的 demethylation。 Hcytreatment 与 aconcentration 在时代基因的倡导者区域导致了 de novo methylation --并且对待时间依赖者举止,并且在 SMCproliferation.These 数据上支持效果的一个剂量依赖者显示为动脉粥样硬化的二个风险因素有在 SMCs.However 的时代基因的倡导者区域导致 de novo methylation 的功能, ox-LDL 的高集中( 50 mg/L )导致了 demethylation ,显示有不同力量力量的动脉粥样硬化的不同风险因素在时代基因的倡导者区域引起不同异常 methylation 模式。Hcy 的 atherogenic 机制可能包含 hypermethylationof 时代基因,在动脉粥样硬化患者损害导致 SMC 的增长。Yushan HUANG~1 Kejun PENG~2 Juan SU~1 Yuping HUANG~3 Yizhon XU~1 and Shuren WANG~1 ~1Department of Pathophysiology,West China School of Preclinic Medical Sciences & Forensic Medicine,Sichuan University,Chengdu 610041.China ~2Department of Laboratory Medicine,Chengdu Medical College,Chengdu 610500,China ~3Department of Biochemistry and Molecular Bilogy,Gannan Medical College,Ganzhou 341000,China 2007Acta Biochimica et Biophysica Sinica2007,39,1:25
13Advanced landfill leachate treatment using a two-stage UASB-SBR system at low temperature显示文摘A two-stage upflow anaerobic sludge blanket(UASB) and sequencing batch reactor(SBR) system was introduced to treat landfill leachate for advanced removal of COD and nitrogen at low temperature.In order to improve the total nitrogen(TN) removal efficiency and to reduce the COD requirement for denitrification,the raw leachate with recycled SBR nitrification supernatant was pumped into the first-stage UASB(UASB1) to achieve simultaneous denitrification and methanogenesis.The results showed that UASB1 played an important role in COD removal and UASB2 and SBR further enhanced the nutrient removal efficiency.When the organic loading rates of UASB1,UASB2 and SBR were 11.95,1.63 and 1.29 kg COD/(m3·day),respectively,the total COD removal efficiency of the whole system reached 96.7%.The SBR acted as the real undertaker for NH4+-N removal due to aerobic nitrification.The system obtained about 99.7% of NH4+-N removal efficiency at relatively low temperature(14.9-10.9°C).More than 98.3% TN was removed through complete denitrification in UASB1 and SBR.In addition,temperature had a significant effiect on the rates of nitrification and denitrification rather than the removal of TN and NH4+-N once the complete nitrification and denitrification were achieved.Hongwei Sun,Qing Yang,Yongzhen Peng,Xiaoning Shi,Shuying Wang,Shujun Zhang Key Laboratory of Beijing Water Quality Science and Water Envirocnnment Recovery Engineering,Beijing University of Technology,Beijing 100124,China 2010Journal of Environmental Sciences2010,22,4:26
14Effect of HCV NS_3 protein on P53 protein expression in hepatocarcinogenesis显示文摘NTRODUCTIONHepatocelularcarcinoma(HCC)isoneofthemostcommonhumancancersintheworld.Recently,theHCVinfectionwasfoundtobeanetiolo...FENG De Yun, CHEN Rui Xue, PENG Yong, ZHENG Hui and YAN Ya Hui 1999World Journal of Gastroenterology1999,5,1:25
15Effects of Meat and Phosphate Level on Water-Holding Capacity and Texture of Emulsion-Type Sausage During Storage显示文摘This paper was designed to verify the influence of phosphate on water-holding capacity (WHC) and texture of emulsiontype sausage prepared with pre-rigor meat,ageing meat or frozen meat.Pre-rigor pork,ageing pork and frozen pork were pre-blended with five levels of phosphate and made into emulsion-type sausage.The yield,hardness and total expressible fluid (TEF) were measured with texture profile analysis machine and pressiometer when emulsion-type sausage was produced.Meanwhile,hardness and purge loss (PL) were measured during 30 d storage.As emusion-type sausage made by pre-rigor meat,higher yield and relatively stable hardness could be found.It indicated that increasing of phosphate level caused an alleviatable effects in increasing of hardness when emulsion-type sausage made by pre-rigor meat,but opposite effects made by ageing meat or frozen meat.The distribution of PL of emulsion-type sausage was found to be affected by phosphate addition.Significant decrease of PL could not be obtained by increasing of phosphate level during storage.Pre-rigor meat improved WHC and texture of emulsion-type sausage.Problem of WHC and texture of emulsiontype sausage during storage could not be resolved by single use of phosphate at relatively higher level (3%) of NaCl.WANG Peng,XU Xing-lian and ZHOU Guang-hong Key Laboratory of Meat Processing and Quality Control,Ministry of Education/Nanjing Agricultural University,Nanjing 210095,P.R.China 2009Agricultural Sciences in China2009,8,12:24
16Hydrogen peroxide-induced changes in intracellular pH of guard cells precede stomatal closure显示文摘Epidermal bioassay demonstrated that benzylamine, a membrane-permeable weak base, can mimick hydrogen peroxide (H2O2) to induce stomatal closure, and butyric acid, a membrane-permeable weak acid, can partly abolish the H2O2-induced stomatal closure. Confocal pH mapping with the probe 5-(and-6)- carboxy seminaphthorhodafluor- 1 - acetoxymethylester (SNARF-1-AM) revealed that H2O2 leads to rapid changes in cytoplasmic and vacuolar pH in guard cells of Viola faba L, i. e. alkalinization of cytoplasmic areas occur red in parallel with a decrease of the vacuolar pH, and that butyric acid pretreatment can abolish alkalinization of cytoplasmic areas and acidification of vacuolar areas of guard cells challenged with H2O2. These results imply that the alkalinization of cytoplasm via efflux of cytosol protons into the vacuole in guard cells challenged with H2O2 is important at an early stage in the signal cascade leading to stomatal closure.ZHANG XIAO, FA CAI DONG, JUN FENG GAO, CHUN PENG SONG (Department of Biology, Henan University, Kaifeng 475001, China) (College of Life Sciences, Northwest Sci-Tech University of Agriculture and Forestry, Yangling 712100, China) 2001Cell Research2001,11,1:24
17Single-photon computational 3D imaging at 45 km显示文摘Single-photon light detection and ranging(lidar)offers single-photon sensitivity and picosecond timing resolution,which is desirable for high-precision three-dimensional(3 D)imaging over long distances.Despite important progress,further extending the imaging range presents enormous challenges because only a few echo photons return and are mixed with strong noise.Here,we tackled these challenges by constructing a high-efficiency,low-noise coaxial single-photon lidar system and developing a long-range-tailored computational algorithm that provides high photon efficiency and good noise tolerance.Using this technique,we experimentally demonstrated active single-photon 3 D imaging at a distance of up to 45 km in an urban environment,with a low return-signal level of^1 photon per pixel.Our system is feasible for imaging at a few hundreds of kilometers by refining the setup,and thus represents a step towards low-power and high-resolution lidar over extra-long ranges.ZHENG-PING LI XIN HUANG YUAN CAO BIN WANG YU-HUAI LI WEIJIE JIN CHAO YU JUN ZHANG QIANG ZHANG CHENG-ZHI PENG FEIHU XU AND JIAN-WEI PAN 2020Photonics Research2020,8,9:24
18Multipliers on Dirichlet Type SpacesPeng Yan HU Department of Mathematics. Normal College of Shenzhen University. Shenzhen. Guangdong 518060. P. R. China Ji Huai SHI Department of Mathematics. University of Science and Technology of China. Hefei. Anhui 230026, P. R. China 2001Acta Mathematica Sinica,English Series2001,17,2:23
19Experimental study on hydrodynamic effect of orientation micro-pored surfaces显示文摘The orientation of the dimple increases the flow distance in the dimple and produces fluid cumulative effect in the dimple length direction, which leads to obvious hydrodynamic effect as a result. In order to investigate the hydrodynamic effect of orientation dimples, a series of experiments was carried out on a ring-on-ring test. Multi-pored faces were tested with different dimple inclination angles and slender ratios. Film thickness and frictional torque were measured under different conditions of load and rotation speed. Experimental results showed that the orientation dimple could produce obvious dynamic effect by change of the flow direction and the increasing dimple orientation leads to increase of the load capability. The hydrodynamic effect strongly depends on dimple orientation parameters such as inclination angle and slender ratio. A larger load capability can be available by increasing dimple orientation and rotation speed. Experimental results agreed well with the theory that orientation micro-pores can significantly improve hydrodynamic performance of surfaces.BAI ShaoXian1,2, PENG XuDong1,2, LI JiYun1,2 & MENG XiangKai1,2 1College of Mechanical Engineering, Zhejiang University of Technology, Hangzhou 310032, China 2Key Laboratory of Special Purpose Equipment and Advanced Processing Technology, Ministry of Education, Zhejiang University of Technology, Hangzhou 310032, China 2011Science China(Technological Sciences)2011,54,3:20
20Progress and significance in research on the early Middle Cambrian Kaili Biota, Guizhou Province, China显示文摘Important progress in research on the Kaili Biota has been made recently. Many interesting components from Chengjiang Biota and Burgess Shale Biota have been discovered, e.g. Microdictyon of lobopodia; Ottoia, Palaeoscolex of worms; Naraoia, Marrella of Trilobitioidea, Mollisonia, anamalocarids and other non-trilobite arthropods; and new sorts of echinoder-mas, macroalage fossils and so on. Recent work on the Kaili Biota has resulted in the following developments: (i) an increase in the number of animal genera, up to more than 100 genera in total, so that the Kaili Biota has become the third most diverse of the Burgess Shale-type Biota after the Burgess Shale and Chengjiang Biotas; and (ii) the most noteworthy fossils in the Kaili Biota are echinoderms, non-trilobite arthropods and soft-bodied medusiform fossils, especially the most diverse echinoderms. The progress provides envidence for the biodiversity of marine organisms presented after the 'Cambrian Explosion' and serves as a link between the earlist Cambrian Chengjiang Biota and late early Middle Cambrian Burgess Shale Biota. It is of great significance in the reconstruction of the Cambrian palaeoplate, palaeongeography and in research on taphonomy.ZHAO Yuanlong, YUAN Jinliang, ZHU Maoyan, YANG Ruidong, GUO Qingjun, PENG Jin and YANG Xinglian(1. Institute of Paleontology and Biomineralization, School of Resource and Environment, Guizhou University of Technology, Guiyang 550003, China: 2. Nanjing Institute of Geology and Paleontology, Chinese Academy of Sciences, Nanjing 210008, China 3. Guiyang Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550003, China) 2002Progress in Natural Science:Materials International2002,12,9:20
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