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Arginine bi-directional translocation and breakdown into ornithine along the arbuscular mycorrhizal mycelium

Science China(Life sciences) 2009年第4期52卷 381-389页

作者： JIN HaiRu College of Chemistry and Life sciences, zhejiang Normal university, Jinhua 321004, China College of Chemistry and Life sciences Zhejiang Normal University Jinhua 321004 China

Bi-directional translocation and degradation of Arginine (Arg) along the arbuscular mycorrhizal (AM) fungal mycelium were testified through 15N and/or 13C isotopic labeling. In vitro mycorrhizas of Glomus intraradices and Ri T-DNA-transformed carrot roots were grown in dual compartment Petri dishes. [15N- and/or13C]Arg was supplied to either the fungal compartment or the mycorrhizal compartment or separate dishes containing the uncolonized roots. The levels and labeling of free amino acids (AAs) in the mycorrhizal roots and in the extraradical mycelia(ERM) were measured by gas chromatogra- phy/mass spectrometry (GC-MS) and high-performance liquid chromatography (HPLC). The ERM of AM fungi exposed in either NH4+ or urea as sole external nitrogen source had much higher 15N enrichment of Arg, compared with those in nitrate or exogenous Arg; however, glycerol supplied as an external car- bon source to the ERM had no significant effect on the level of Arg in the ERM. Meanwhile, Arg bio- synthesized in the ERM could be translocated intact to the mycorrhizal roots and thereby the level of Arg in the mycorrhizal roots increased to about 20% after culture of ERM in 4 mmol/L NH4+ for 6 weeks. Also Arg was found to be bi-directionally transported along the AM fungal mycelium through [U-13C]Arg labeling either in the mycorrhizal compartment or in the fungal compartment. Once Arg was translo- cated to the potential N-limited sites, it would be further degraded into ornithine (Orn) and urea since either [U-13C] or [U-15N/U-13C]Orn was apparently shown up in the mycorrhizal root tissues when [U-13C] or [U-15N/U-13C]Arg was labeled in the fungal compartment, respectively. Evidently Orn formation indi- cated the ongoing activities of Arg translocation and degradation through the urea cycle in AM fungal mycelium.

关键词： arbuscular mycorrhiza arginine in vitro culture 15N labeling ornithine urea cycle

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Report on Cardiovascular Health and Diseases in China 2023:An Updated Summary

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Biomedical and Environmental sciences 2024年第9期37卷 949-992页

作者： National center for Cardiovascular Diseases The Writing Committee of the Report on Cardiovascular Health and Diseases in China Shengshou Hu .

Since 1990,China has made considerable progress in resolving the problem of“treatment difficulty”of cardiovascular diseases(CVD).The prevalent unhealthy lifestyle among Chinese residents has exposed a massive proportion of the population to CVD risk factors,and this situation is further worsened due to the accelerated aging population in *** remains one of the greatest threats to the health of Chinese *** terms of the proportions of disease mortality among urban and rural residents in China,CVD has persistently ranked *** 2021,CVD accounted for 48.98%and 47.35%of deaths in rural and urban areas,*** out of every five deaths can be attributed to *** implement a national policy“focusing on the primary health institute and emphasizing prevention”and truly achieve a shift of CVD prevention and treatment from hospitals to communities,the National center for Cardiovascular Diseases has organized experts from relevant fields across China to compile the“Report on Cardiovascular Health and Diseases in China”annually since *** 2024 report is established based on representative,published,and high-quality big-data research results from cross-sectional and cohort population epidemiological surveys,randomized controlled clinical trials,large sample registry studies,and typical community prevention and treatment cases,along with data from some projects undertaken by the National center for Cardiovascular *** firsthand data not only enrich the content of the current report but also provide a more timely and comprehensive reflection of the status of CVD prevention and treatment in China.

关键词： Cardiovascular disease Risk factor Prevalence Mortality Rehabilitation Basic research Medical device development Health economics

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Two new types of bounded waves of CH-γ equation

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Science China Mathematics 2005年第12期48卷 1618-1630页

作者： GUO Boling & LIU Zhengrong Institute of Applied Physics and Computational Mathematics, Beijing 100088, China School of mathematical sciences and center for Nonlinear Science Studies, South China university of Technology, Guangzhou 510640, China 1. Institute of Applied Physics and Computational Mathematics 100088 Beijing China 2. School of mathematical sciences and center for Nonlinear Science Studies South China University of Technology 510640 Guangzhou China

In this paper, the bifurcation method of dynamical systems and numerical approach of differential equations are employed to study CH-γ equation. Two new types of bounded waves are found. One of them is called the compacton. The other is called the generalized kink wave. Their planar graphs are simulated and their implicit expressions are given. The identity of theoretical derivation and numerical simulation is displayed.

关键词： CH-γ equation,compactons,generalized kink waves.

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Koszul Differential Graded Algebras and BGG Correspondence II

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Chinese Annals of Mathematics,Series B 2010年第1期31卷 133-144页

作者： Jiwei HE Quanshui WU Department of Mathematics Shaoxing College of Arts and Sciences Shaoxing 312000 Zhejiang China School of mathematical sciences Fudan University Shanghai 200433 China

The concept of Koszul differential graded (DG for short) algebra is introduced in [8].Let A be a Koszul DG *** the Ext-algebra of A is finite-dimensional,i.e.,the trivial module A k is a compact object in the derived category of DG A-modules,then it is shown in [8] that A has many nice ***,if the Ext-algebra is infinitedimensional,little is known about *** shown in [15] (see also Proposition 2.2),A k is not compact if H(A) is *** this paper,it is proved that the Koszul duality theorem also holds when H(A) is finite-dimensional by using Foxby duality.A DG version of the BGG correspondence is deduced from the Koszul duality theorem.

关键词： Koszul differential graded algebra Koszul duality BGG correspondence

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Sharpness on the Lower Bound of the Lifespan of Solutions to Nonlinear Wave Equations

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Chinese Annals of Mathematics,Series B 2011年第4期32卷 521-526页

作者： Yi ZHOU 1 Wei HAN 2 1 Nonlinear mathematical Modeling and Methods Laboratory Shanghai Key Laboratory for Contem- porary Applied Mathematics School of mathematical sciences, Fudan university, Shanghai 200433, China. 2 School of mathematical sciences, Fudan university, Shanghai 200433, China Department of Mathematics, North university of China, Taiyuan 030051, China. Nonlinear mathematical Modeling and Methods Laboratory Shanghai Key Laboratory for Contemporary Applied Mathematics School of Mathematical Sciences Fudan University Shanghai 200433 China

This paper is devoted to proving the sharpness on the lower bound of the lifespan of classical solutions to general nonlinear wave equations with small initial data in the case n = 2 and cubic nonlinearity （see the results of T. T. Li and Y. M. Chen in 1992）. For this purpose, the authors consider the following Cauchy problem： { where □=δt^2-∑i=1n δx^^2 is the wave operator, g（x）（≡/） 0 is a smooth non-negative function with compact support, and ε 〉 0 is a small parameter. It is shown that the solution blows up in a finite time, and the lifespan T（ε） of solutions has an upper bound T（ε） ≤ exp（Aε-2） with a positive constant A independent of ε, which belongs to the same kind of the lower bound of the lifespan.

关键词： Nonlinear wave equation Cauchy problem Lifespan

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The three-dimensional structure of Infectious flacherie virus capsid determined by cryo-electron microscopy

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Science China(Life sciences) 2009年第12期52卷 1186-1191页

作者： XIE Li1,4, ZHANG QinFen2·, LU XingMeng3, DAI XinHong2, LI KunPeng2, HONG Jian1,4· & ZHOU XuePing11 Institute of Biotechnology, zhejiang university, Hangzhou 310029, China 2 State Key Laboratory of Biocontrol, School of Life sciences, Sun Yat-Sen university, Guangzhou 510275, China 3 College of Animal sciences, zhejiang university, Hangzhou 310029, China 4 center of Analysis and Measurement, zhejiang university, Hangzhou 310029, China Institute of Biotechnology Zhejiang University Hangzhou 310029 China State Key Laboratory of Biocontrol School of Life Sciences Sun Yat-Sen University Guangzhou 510275 China College of Animal sciences Zhejiang University Hangzhou 310029 China center of Analysis and Measurement Zhejiang University Hangzhou 310029 China

Cryo-electron microscopy and image reconstruction were used to determine the three-dimensional structure of Infectious flacherie virus (IFV). 5047 particles were selected for the final reconstruction. The FSC curve showed that the resolution of this capsid structure was 18 ·. The structure is a psuedo T=3 (P=3) icosahedral capsid with a diameter of 302.4 · and a single shell thickness of 15 ·. The density map showed that IFV has a smooth surface without any prominent protrude or depression. Comparison of the IFV structure with those of the insect picorna-like virus-Cricket paralysis virus (CrPV)and human picornavirus-Human rhinovirus 14 (HRV 14) revealed that the IFV structure resembles the CrPV structure. The "Rossmann canyon" is absent in both IFV and CrPV particles. The polypeptide topology of IFV VP2, IFV VP3 was predicted and the subunit location at the capsid surface was further analyzed.

关键词： Infectious flacherie virus cryo-electron microscopy three-dimensional structure polypeptide folding

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Genome organization and phylogenetic tree analysis of Garlic virus E,a new member of genus Allexivirus

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Chinese Science Bulletin 2002年第1期47卷 33-37页

作者： CHEN Jiong & CHEN JianpingCollege of Life sciences, zhejiang university, Hangzhou 310029, China Virology Department, zhejiang Academy of Agricultural sciences, Hangzhou 310021, China College of Life sciences Zhejiang University Hangzhou China Virology Department Zhejiang Academy of Agricultural Sciences Hangzhou China

The complete sequence of an Allexivirus iso-lated from garlic plants in Yuhang City, zhejiang Province, China had been determined. The single-strand, positive RNA genome was 8451 nucleotides in length excluding poly(A) tail. The genome organization of this virus was similar to that of the other Allexiviruses but only with 62.8%-64.8% nucleo-tide acid identities. The amino acid sequences of proteins encoded by ORFl-6 shared 67.6%-78.5%, 55.4%-66.2%, 56.7%-66.4%,40.3%-55.6%,66.3%-79.7%and 52.2%-68.8% identities with those of the others respectively. The homology range between it and the other Allexiviruses was similar to that between the other distinct species in this genus. A more comprehensive comparison using all available CP amino acid sequences showed that it shared only 63.9%-79.8% amino acids identical with the others. Therefore, it had been considered as a new member of the genus, named as garlic virus E (GarV-E). Phylogenetic analysis confirmed GarV-E as a distinct member and the correct names

关键词： genus Allexivirus garlic virus E nucleotide sequence classification.

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The Development of Library and Information Profession in the Chinese Academy of sciences

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图书情报工作 1996年第1期 5-11页

作者： Meng GuangjunWang Bing (Documentation and Information center, the Chinese Academy of sciences)

The infrastructure of the library and information system of the Chinese Academy of sciences is introduced, library and information service, and the applications of information technology are studied. The academic acti... 详细信息

关键词： Chinese Academy of sciences\ library and information profession\ China

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Explicit Classification for Torsion Subgroups of Rational Points of Elliptic Curves

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Acta Mathematica Sinica,English Series 2002年第3期18卷 539-548页

作者： De Rong QIU center for Advanced Study, Tsinghua university, Beijing 100084. P. R. China Xian Ke ZHANG Department of mathematical sciences, Tsinghua university, Beijing 100084, P. R. China center for Advanced Study Tsinghua University Beijing P. R. China Department of mathematical sciences Tsinghua University Beijing P. R. China

We study the classification of elliptic curves E over the rationals Q according to the torsion subgroups E_(tors)(Q). More precisely, we classify those elliptic curves with E_(tors)(Q) being cyclic with even orders. We also give explicit formulas for generators of E_(tors)(Q). These results, together with the recent results of K. Ono for the non-cyclic E_(tors)(Q), completely solve the problem of the explicit classification and parameterization when E has a rational point of order 2.

关键词： Elliptic curve Rational point Torsion group Mordell group Parameterization

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China's energy, environment and policy perspective

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Journal of Environmental sciences 2000年第3期12卷 270-274页

作者： ZHANG Shi\|qiu (center for Environmental sciences, Peking university, Beijing 100871, China) center for Environmental sciences Peking University Beijing 100871 China

This paper discusses the specific features of the energy in China, and addresses those key challenges in China is that the co\|exist of (1) higher total energy production and lower per capita level; (2) lower per capita energy resources level with unrational energy consumption structure; (3) lower energy utilization efficiency and higher energy conservation potential; and (4) unequal distribution of energy resources. It reviews the key environmental problems related to the feature of energy production and consumption. Based on the analysis, the author furthers addresses the policy and actions needed.

关键词： energy energy production energy consumption environment policy

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