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Sequence analysis of mRNA polyadenylation signals of rice genes

Chinese Science Bulletin 2006年第9期51卷 1069-1077页

作者： LU Ying1, 2. GAO Chenxi1,2.3.& HAN Bin1,3.41. National {3. for Gene {2., Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 2.02.3. china 2. Graduate School of the Chinese Academy of Sciences, Beijing 10003., china 3. Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 2.003.0} china National center for Gene {2. Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Shanghai China Graduate School of the Chinese Academy of Sciences Beijing China Institute of Plant Physiology and Ecology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Shanghai China

The formation of eukaryotic mRNAs involves the cleavage and polyadenylation of pre- mRNAs. To investigate the sequence requirement of putative polyadenylation signals (PASs), poly(A) sites and downstream elements (DUEs) in 3.-end-pro- cessing in rice, we compared expressed sequences tags (ESTs) with poly(A) extremity to full-length cDNA sequences and constructed a database of 12.69 pre- mRNA sequences in ?40―+40 nt surrounding the poly(A) sites, which were from 9953.genes. The al- ternative poly(A) sites were revealed in approxi- mately 2.% of mRNAs. Nearly 80% of pre-mRNAs showed stringent requirement of the YA (CA or UA) at poly (A) sites for polyadenylation. About 7.9% had the AAUAAA signals on ?40―?1 nt upstream of the poly(A) sites. Over 60% of mRNAs probably used the one- or two-base variants of AAUAAA hexamers as their PASs in 3. fragments. The single-base variants of AAUGAA revealed the high frequency in 11.5% of 3. fragments. The DUEs were detected in 90% of pre- mRNAs, especially more than half of the pre-mRNAs with multi-base variants of AAUAAA had the DUEs surrounding the poly(A) site. The location of DUE is also important for defining the cleavage site. Al- though most of the rice pre-mRNAs did not contain AAUAAA signal, the existence of downstream ele- ments ensured the efficiency of cleavage-polyade-

关键词：多聚腺苷酸序列分析 mRNA 水稻基因工程

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A simple lattice Boltzmann scheme for low Mach number reactive flows

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Science china(Technological Sciences) 2006年第6期49卷 714-726页

作者： CHEN Sheng1,2. LIU Zhaohui2. ZHANG Chao2. HE Zhu2. TIAN Zhiwei2. SHI Baochang 2.& ZHENG Chuguang2.1. Technology center of Wuhan Iron and Steel (Group) Company, Wuhan 43.080, china 2. State Key Laboratory of Coal Combustion, Hua Zhong University of Science and Technology, Wuhan 43.074, china Technology center of Wuhan Iron and Steel (Group) Company Wuhan China State Key Laboratory of Coal Combustion Hua Zhong University of Science and Technology Wuhan China

For simulating low Mach number reactive flows, a simple and coupled lattice Boltzmann (CLB) scheme is proposed, by which the fluid density can bear significant changes. Different from the existing hybrid lattice Boltzmann (HLB) scheme and non-coupled lattice Boltzmann (NCLB) scheme, this scheme is strictly lattice Boltzmann style and the fluid density couples directly with the temperature. Because it has got rid of the constraint of traditional thought in lattice Boltzmann scheme,on the basis of the equality among the particle speed c, the time step △t and the lattice grid spacing △x held, both c and △t can be adjusted in this scheme according to a "characteristic temperature" instead of the local temperature. The whole algorithm becomes more stable and efficient besides inheriting the intrinsically outstanding strong points of conventional lattice Boltz-mann scheme. In this scheme, we also take into account different molecular weights of species, so it is more suitable for simulating actual low Mach number reactive flows than previous work. In this paper, we simulated a so-called "counter-flow" premixed propane-air flame, and the results got by our scheme are much better than that obtained by NCLB. And the more important thing is that the exploration in this work has offered a kind of brand-new train of thought for building other novel lattice Boltzmann scheme in the future.

关键词： lattice Boltzmann, low Mach number flows, reactive flows, simulation.

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Heat treatment of novel low-carbon multi-alloyed anti-wear marine steel

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Progress in Natural Science:Materials International 2011年第3期21卷 254-261页

作者： Jing-hua JIANG~(1,2.,Qiu-yue WANG~1,Ai-bin MA~(1,2.,Jun SHI~1,Liu-yan ZHANG~1, Hui-dong YANG~(2.3.,Fu-min LU~2.Qi ZHOU~2.1.National Engineering research {2. of Water resources efficient Utilization and Engineering safety, Hohai University,nanjing 2.0098,china 2.College of Mechanics and Materials,Hohai University,nanjing 2.0098,china 3.Department of Mechanical and Aerospace Engineering,North Carolina State University, Raleigh,North Carolina 2.695-7919,USA National Engineering research {2. of Water {3. efficient Utilization and Engineering safety Hohai University Nanjing 210098 China College of Mechanics and Materials Hohai University Nanjing 210098 China Department of Mechanical and Aerospace Engineering North Carolina State University Raleigh North Carolina 27695-7919 USA

A low-carbon anti-wear steel,multi-alloyed with Si-Cr-Mn-Al-Ni-Mo-（Nb,RE）,was designed for vane pumps of ships. The novel cast steel after various heat treatments was characterized by microstructure observations and mechanical properties measurement in order to achieve an optimal process correlated with good abrasive resistance for a long marine *** scanning calorimetry and hardness analyses deduced a complete austenitizing temperature of 1 000℃,based on the alloying element homogenization and defective structure elimination without grain *** optimal austempering process（austenitized at 1 000℃,quick cooled for holding at 3.0℃for 1.5 h and then air-cooled to room temperature） produced a uniform mixture structure of fine carbide-free aciculate bainites and few lath martensites,resulting in the tensile strength increase of 3.%and impact toughness increase of 50%compared with that of the as-cast *** abrasive wheel tests show that the austempered steel has good wear resistance with a mass-loss rate of 170 mg/（km·cm2. under applied load of 70 N in acidic *** new grade steel （containing anti-corrosion elements of Cr and rare earth） can find wide application in marine engineering,with further enhanced comprehensive properties via melting process improvement.

关键词： abrasive resistance carbide-free bainite marine steel mechanical performance heat treatment

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Determination of Young's modulus by nanoindentation

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Science china(Technological Sciences) 2004年第4期47卷 398-408页

作者： MA Dejun1, Chung Wo Ong2. LIU Jianmin1 & HE Jiawen3.1. Surface Engineering research Institute, CMES, Beijing 100072. {3. 2. Department of Applied Physics and Materials research center, The Hong Kong Polytechnic University, Hong Kong, {3. 3. State Key Laboratory for Mechanical Behavior of Materials, Xian Jiaotong University, Xian 710049, {3. Surface Engineering research Institute CMES Beijing China Department of Applied Physics and Materials research center The Hong Kong Polytechnic University Hong Kong China State Key Laboratory for Mechanical Behavior of Materials Xi’an Jiaotong University Xi’an China

A methodology for determining Youngs modulus of materials by non-ideally sharp indentation has been developed. According to the principle of the same area-to-depth ratio, a non-ideally pyramidal indenter like a Berkovich one can be approximated by a non-ideally conical indenter with a spherical cap at the tip. By applying dimensional and finite element analysis to the non-ideally conical indentation, a set of approximate one-to-one relationships between the ratio of nominal hardness/reduced Youngs modulus and the ratio of elastic work/total work, which correspond to different tip bluntness, have been revealed. The nominal hardness is defined as the maximum indentation load divided by the cross-section area of the conical indenter specified at the maximum indentation depth. As a consequence, Youngs modulus can be determined from a nanoindentation test only using the maximum indentation load and depth, and the work done during loading and unloading processes. The new method for determining Youngs modulus is referred to as pure energy method. The validity of the method was examined by performing indentation tests on five materials. The experimental results and the standard reference values are in good agreement, indicating that the proposed pure energy method is a promising substitution for the most widely used analysis models at present.

关键词： Young's modulus, nanoindentation, nominal hardness, indentation work.

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Speciation of the elements and compositions on the surfaces of dust storm particles:The evidence for the coupling of iron with sulfur in aerosol during the long-range transport

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Chinese Science Bulletin 2005年第8期50卷 738-744页

作者： ZHANG Xingying1,2. ZHUANG Guoshun1,2.3. CHEN Jianmin2.& XUE Huaxin2.1. center for Atmospheric Environment Study, Department of Chemistry, Beijing Normal University, Beijing 100875, china 2. center for Atmospheric Chemistry Study, Department of Environ- mental Science and Engineering, Fudan University, Shanghai 2.043., china 3. LAPC/NZC, Institute of Atmospheric Physics, NZC/LAPC, Chinese Academy of Sciences, Beijing 10002., china center for Atmospheric Environment Study Department of Chemistry Beijing Normal University Beijing 100875 China center for Atmospheric Chemistry Study Department of Environmental Science and Engineering Fudan University Shanghai 200433 China LAPC/NZC Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China

The speciation of the elements on the surface of the particles collected during dust storm and non-dust storm in Beijing and Inner Mongolia was studied by XPS. The ma- jor species of iron on the surface were oxides, sulfate, silicate, FeOOH and minor part sorbed on SiO2.Al2.3. Sulfate is the dominant species of sulfur on the surface. SiO2.and Al2.3.are the main components of Si and Al on the surface respectively. One of the most important findings was that the Fe(II) (FeS and FeSO4) produced could account for up to 44.3. and 45.6% of the total Fe on the surface in the aerosol sample collected at that night and next day of the “peak” time of the dust storm occurring on March 2., 2.02. while Fe2.SO4)3. one of the Fe(III) species on the surface decreased from 67.1% to 49.5% and 48.0% respectively. Both S and Fe en- riched on the surface of aerosol particles. Fe(II) accounted for 1.3.?5.3. of total Fe in bulk aerosol samples during dust storm. These results provided strong evidence to sup- port the hypothesis of the coupling between iron and sulfur in aerosols during the long-range transport, which would have important impact on the global biogeochemical cycle.

关键词：物种形成原理 XPS 大气悬浮物 Fe-S结合粒子集合

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Discovery of seep carbonate nodules as new evidence for gas venting on the northern continental slope of South china Sea

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Chinese Science Bulletin 2006年第10期51卷 1228-1237页

作者： CHEN Zhong1,2.3. YAN Wen1,2.3. CHEN Muhong1,3. WANG Shuhong1,2.3. LU Jun1,3. ZHANG Fan1,3. XIANG Rong1,3. XIAO Shangbin1,3. YAN Pin1,2.3.& GU Senchang1,2.3.1. South china Sea Institute of Oceanology, Chinese Academy of Sci-ences, Guangzhou 5103.1, china 2. Guangzhou {2. for Gas Hydrate research, Chinese Academy of Sciences, Guangzhou 5103.1, china 3. Key Laboratory of Marginal Sea Geology, South china Sea Institute of Oceanology and Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 5103.1, china South china Sea Institute of Oceanology Chinese Academy of Sciences Guangzhou China Guangzhou center for Gas Hydrate research Chinese Academy of Sciences Guangzhou China Key Laboratory of Marginal Sea Geology South China Sea Institute of Oceanology and Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou China

Seep carbonate nodules were firstlycollected from the southwestern Dongsha area onnorthern continental slope of South china Sea formineralogical and geochemical studies. The resultsof X-ray diffraction show that carbonate nodules arecomposed of Fe-rich domolite,siderite and a few cal-cite and aragonite, as well as a small quantity ofnon-carbonate minerals such as goethite, quartz andclay minerals. Fe-rich dolomite and siderite charac-terized by euhedral microcrystalline structure weredirectly precipitated at cold seeps. The δ 13. valuesfor Fe-rich dolomite and siderite in the bulk nodulesvary from ?18.2.‰ to ?3..07‰, and the δ 18O valuesrange from 0.42.to 2.76‰. Their moderate depleted13. reflects that carbon origin is possibly thermoge- netic gas or mixed gas, which is evidence of gasventings in the seafloor. Moreover, massive wormtube fossils related to cold seeps were found on thesurfaces of carbonate nodules, and the conduitsand/or channels in semi-solidified nodules whichwere not filled by carbonate or sediment were alsoobserved. A preliminary conclusion is that activemicro gas venting with a conduit/channel diameterrange from 2.0 μm to 600 μm possibly exists inmodern seafloor of the carbonate nodule area.

关键词：渗出碳酸盐节碳氧同位素甲烷渗漏天然气水化物

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A preliminary study on vegetation-erosion dynamics and its applications

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Science china Earth Sciences 2005年第5期48卷 689-700页

作者： WANG Zhaoyin 1,2., WANG Guangqian 1 , LI Changzhi 1 & WANG Feixin 1 1. Department of Hydraulic Engineering, Tsinghua University, Beijing 100084, china 2. Intern{3. {2. and Training center on Erosion and Sedimentation, Beijing 100084, china Department of Hydraulic Engineering Tsinghua University Beijing China International research and Training {2. on Erosion and Sedimentation Beijing China

Vegetation-erosion dynamics is a new interdisciplinary science, studying the laws of evolution of watershed vegetation under the action of various ecological stresses. Introducing a qualitative expression of ecological stresses in this paper, the present authors establish the cou- pled differential equations for the vegetation-erosion process and derive a theoretical solution. The model is applied to the Anjiagou watershed on the Loess Pateau and the Xiaojiang water- shed and its sub-watersheds on the Yunnan Plateau. The calculated results agree well with the vegetation development processes. Abstracted from the differential equations the so-called vegetation-erosion chart is worked out, with which we can predict the development trend of vegetation under no human stresses. It is demonstrated that the erosion control is important for vegetation development and reforestation must be a long-term strategy. On the Yunnan Plateau with relatively high precipitation and temperature, vegetation can be greatly improved if erosion is controlled. On the dry and cold Loess Pateau suffering from high rate of soil erosion, however, vegetation can effectively control erosion but erosion reduction exhibits low effectiveness on vegetation development. Vegetation in the area is not stable and management is always needed to maintain the vegetation.

关键词： vegetation-erosion dynamics, human activities, coupled differential equations, erosion control, vigor ofvegetation.

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Orientational phase transition in C_(60) single crystal under high pressure

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Chinese Science Bulletin 1998年第16期43卷 1341-1344页

作者： XIE Bin+1, WANG Haiqian+1, WANG Qiang+1, HOU Jianguo+1, XU Bo+2. TAN Mingqiu+2. LI Hongnian+2.and XU Yabo+2.1. Structure research Laboratory and center for Fundamental Physics, University of Science and Technology of {2., Hefei 2.002., {2. 2. Depart Structure research Laboratory and center for Fundamental Physics University of Science and Technology of China Hefei China Department of Physics Zhejiang University Hangzhou China

By using a piston-cylinder type hydrostatic high-pressure unit, the electrical dc conductance of bulk C 60 single crystal was measured in the pressure range of 0 to 0.6 GPa at 2.0 K. With increasing pressure, a discontinuous increase of the conductance was observed at the pressure of 0.176 GPa, which can be ascribed to the orientational ordering phase transition. In the simple cubic phase, the increase of conductance with increasing pressure is faster than that in the face-centered-cubic phase.

关键词： C 60 high pressure conductivity.

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Structural stability of infinite-layer CaCuO_2.under high pressure

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Chinese Science Bulletin 2003年第12期48卷 1201-1203页

作者： QIN Xiaomei1,2. HONG Ming1,2. ZHANG Gongmu1,2. MAI Wenjie1,2. LI Fengying1,2. YU Richeng1,2. LIU Jing2.3.& JIN Changqing1,2.1. Institute of Physics, Chinese Academy of Sciences, Beijing 100080, china 2. Beijing High Pressure research {2., Beijing 100080, china 3. Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 10003., china Correspondence should be addressed to Jin Changqing (e-mail: cqjin@ ***) Institute of Physics Chinese Academy of Sciences Beijing 100080 China Beijing High Pressure research center Beijing 100080 China Institute of High Energy Physics Chinese Academy of Sciences Beijing 100039 China

In situ high-pressure energy dispersive X-ray diffraction measurements on polycrystalline powder Ca-CuO2.with an infinite layer structure (IL CaCuO2. have been performed by using diamond anvil cell (DAC) instrument with synchrotron radiation. The results suggest that the crystal structure of IL CaCuO2.is stable under pressure up to 3. GPa at room temperature. According to Birch-Murn- aghan equation of state, assuming pressure derivative 4,=0Bthe bulk modulus B0=181 ?9 GPa is obtained.

关键词： infinite-layer CaCuO2 synchrotron radiation high pressure energy dispersive X-ray diffraction.

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Dispersion of ventricular mRNA of RyR2.and SERCA2.associated with arrhythmogenesis in rats

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Acta Pharmacologica Sinica 2004年第6期25卷 36-41页

作者： Hong-lan WANG, De-zai DAI2. Feng GAO3. Yan-pin ZHANG3. Feng LU research Division of Pharmacology, china Pharmaceutical University, {2. 2.0009, china 3.aboratorial center ofMedicine, Southeast University, {2. 2.0009, china research Division of Pharmacology China Pharmaceutical University Nanjing 210009 Laboratorial center of Medicine Southeast University Nanjing 210009

AIM: To investigate the effect of CPU86017 on the changes of mRNA abundance of different calcium handling system in infarcted heart. METHODS: Rats were subjected to left coronary ligation to induce myocardial infarc- tion (MI). The treatment with either propranolol (Pro) 5 mg/kg ip or CPU86017 1, 2. and 4 mg/kg ip was initiated on the next day of operation and continued for 2. d. Medication with isoproterenol (Isop) 3.mg/kg sc started on the d 17-2.. Ventricular mRNA abundance of ryanodine receptor 2.(RyR2., sarcoplasmic reticulum Ca2.-ATPase (SERCA2., L-type Ca2. channel, and Na+/Ca2.exchanger (NCX1) were measured. RESULTS: Arrhythmic scores (AS) in the Isop group was raised up to 5.2.±1.75 (P2.2.±2.04 and sham group 1.50±1.73. The AS was depressed by Pro (1.63.1.53. P2.and 4 mg/kg (3.00±1.2., and 1.70±1.85, P2. and SERCA2.was associated with an increase in AS in Isop group, and it was much depressed in the left than the right ventricle. The dispersion and depression of mRNA were restored significantly by Pro and CPU86017, asso- ciated with suppression on AS. In Isop group, the mRNA abundance of L-type Ca2. channel was not changed; and a moderate increase in the mRNA of NCX1 was seen, the changes were regressed by Pro and CPU86017. CONCLUSION: Isop-induced arrhythmogenesis in MI heart was correlated mainly with a dispersion of depressed mRNA abundance in ventricle likely due to the consequence of PKA over-phosphorylation. A suppression of arrhythmia by Pro and CPU86017 resulted from a regression of the dispersion and depression of RyR2.and SERCA2.

关键词： myocardial infarction isoproterenol arrhythmia calcium 4-chlorobenzyltetrahydroberberine

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