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Effect of Antibiotic Treatment on Toxin Production by Alexandrium tamarense

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Biomedical and environmental Sciences 2003年第4期16卷 340-347页

作者： CHANG-HAI WANG, YI-YUN WANG, YING-YING SUN, AND XIAN-TANG XIEDepartment of Bioengineering, dalian university of Technology, dalian 11602., liaoning, china Department of Bioengineering Dalian University of Technology Dalian 116024 Liaoning Chin

Objective Impact of the presence of bacteria associated with a marine dinoflagellate, Alexandrium tamarense CI01, on the growth and toxin production of the algae in batch culture was investigated. Methods Pronounced changes in the activities of the algal culture were observed when the culture was treated with different doses of a mixture of penicillin and streptomycin. Results In the presence of antibiotics at the initial concentration of 100 u/mL in culture medium, both algal growth and toxin yield increased markedly. When the concentration of antibiotics was increased to 500 u/mL, the microalgal growth was inhibited, but resumed in a few days to eventually reach the same level of growth and toxin production as at the lower dose of the antibiotics. When the antibiotics were present at a concentration of 1 000 u/mL, the algal growth was inhibited permanently. Conclusions The results indicate that antibiotics can enhance algal growth and toxin production not only through their inhibition of the growth and hence competition for nutrients, but also through their effects on the physiology of the algae.

关键词： Alexandrium tamarense Harmful algal bloom Antibiotic Toxin Saxitoxin

A theorem of Fong's type for graded algebras

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Science china Mathematics 2005年第5期48卷 577-582页

作者： FAN Yun & ZHU Ping school of Mathematics and Statistics, Central china {2. university, Wuhan 430079, china school of Mathematical Science, Nankai university, Tianjin 300071, china school of Mathematics and Statistics Central China Normal University Wuhan China school of Mathematical Science Nankai University Tianjin China

Let G be a finite p-solvable group and k be an algebraic closed field of characteristic p. It is proved that any projective indecomposable module of a G-graded k-algebra is an induced module of a module of the subalgebra graded by a Hall p′-subgroup. A necessary and sufficient condition for the indecomposability of an induced module from a Hall p′-subgroup is obtained.

关键词： group graded algebra indecomposable induced module primitive idempotent.

A differentiable sphere theorem with positive Ricci curvature and reverse volume pinching

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Science china Mathematics 2011年第3期54卷 603-610页

作者： WANG PeiHe1 & WEN YuLiang2.1school of Mathematical Sciences, Qufu normal {2., Qufu 2.3165, china 2.epartment of Mathematics, East china normal {2., Shanghai 2.02.1, china school of Mathematical Sciences Qufu Normal University Department of Mathematics East China Normal University

Let Mn be a compact, simply connected n (≥3)-dimensional Riemannian manifold without bound-ary and Sn be the unit sphere Euclidean space Rn+1. We derive a differentiable sphere theorem whenever themanifold concerned satisfies that the sectional curvature KM is not larger than 1, while Ric(M)≥n+2.4 and the volume V (M) is not larger than (1 + η)V (Sn) for some positive number η depending only on n.

关键词： k-th Ricci curvature Hausdorff convergence differentiable sphere theorem harmonic coordinate harmonic radius

A note for preconditioning nonsymmetric matrices

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Applied Mathematics(A Journal of Chinese Universities) 2010年第1期25卷 93-100页

作者： CHEN Xiao-shan LI Wen school of Mathematics, South china {2. university, Guangzhou 510631, china school of Mathematics South China Normal University Guangzhou China

In this paper, we consider preconditioners for generalized saddle point systems with a nonsymmetric coefficient matrix. A constraint preconditioner for this systems is constructed, and some spectral properties of the ... 详细信息

关键词： Preconditioner saddle point matrix minimal polynomial Schilder's factorization.

Global Existence of Classical Solutions for Some Oldroyd-B Model via the Incompressible Limit

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Chinese Annals of Mathematics,Series B 2006年第5期27卷 565-580页

作者： Zhen LEI school of Mathematical Sciences, Fudan university, Shanghai 2.0433,{2. school of Mathematics and Statistics, Northeast normal university, Changchun 13002.,{2.. school of Mathematical Sciences Fudan University Shanghai 200433 China

In this paper, we prove local and global existence of classical solutions for a system of equations concerning an incompressible viscoelastic fluid of Oldroyd-B type via the incompressible limit when the initial data ... 详细信息

关键词： Incompressible limit Global existence Oldroyd model

Optimal value functions of generalized semi-infinite min-max programming on a noncompact set

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Science china Mathematics 2005年第2期48卷 261-276页

作者： WANG Changyu, YANG Xiaoqi & YANG Xinmin Institute oi Operations Research, Qufu normal university, Qufu 2.3165,{2. Department of Applied Mathematics, dalian university of Technology, dalian 11602.,{2. Department of Applied Mathematics, The Hong Kong Polytechnic university, Hong Kong,{2. Department of Mathematics, Chongqing normal university, Chongqing 400047,{2. Institute of Operations Research Qufu Normal University Qufu China Department of Applied Mathematics Dalian University of Technology Dalian China Department of Applied Mathematics The Hong Kong Polytechnic University Hong Kong China Department of Mathematics Chongqing Normal University Chongqing China

In this paper, we study optimal value functions of generalized semi-infinite min-max programming problems on a noncompact set. Directional derivatives and subdifferential characterizations of optimal value functions are given. Using these properties,we establish first order optimality conditions for unconstrained generalized semi-infinite programming problems.

关键词： optimal value function, directional derivative, subdifferential, semi-infinite programming, first order optimality condition.

New Solution to Surface Temperature of Casting Slab Measurement Based on Preceded Reflector and Multi-Wavelength

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Journal of Iron and Steel Research International 2012年第8期19卷 12-16页

作者： LIU Jun1, MA Jiao-cheng2. YANG Feng3, XIAO Hui1, RAO Li-min1 (1. school of Nuclear Engineering and Technology, East china Institute of Technology, Fuzhou 344000, Jiangxi, china 2. school of Mechanical Engineering and Automation, Northeastern university, Shenyang 110004, liaoning, china 3. school of Civil and environmental Engineering, East china Institute of Technology, Fuzhou 344000, Jiangxi, china) school of Nuclear Engineering and Technology East China Institute of Technology Fuzhou Jiangxi China school of Mechanical Engineering and Automation Northeastern University Shenyang Liaoning China school of Civil and environmental Engineering East China Institute of Technology Fuzhou Jiangxi China

The surface temperature of casting slab is an important parameter in the metallurgy field. Because the surface emissivity is uncertain and also unknown, it is difficult to measure the slab surface temperature accurately. A method based on preceded reflector and multi-wavelength was put forward to deal with the difficulty in surface temperature measurement of casting slab. On the premise of preceded reflector and non-preceded reflector, the method establishes the radiation energy equations and works out the emissivity and temperature in the equations. Also, the multilayer modeling of casting slab surface and multiple reflection-absorption process modeling were built by Monte Carlo method. The temperature measuring method had been applied in the continuous casting field. In order to verify the measured result, the thermal imaging method was adopted when the slab surface emissivity was set by repeated tests. Finally, the measured and verified temperature curves keep a same tendency and the error of the values is lower than 5℃. The comparison result shows that the method can measure temperature accurately.

关键词： casting slab emissivity surface temperature preceded reflector multi-wavelength

ON ABSOLUTE STABILITY OF CONTROL SYSTEM WITH SEVERAL EXECUTIVE ELEMENTS

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Science in china,Ser.A 1988年第4期31卷 395-405页

作者：赵素霞 Department of Mathematics liaoning normal {2. dalian

In this paper, we study the absolute stability of control system with several executive elements by means of Liapunov’s functions of the Lur’e form. We obtain some necessary and sufficient conditions for V<0. From these conditions we obtain a very general algebraic criterion for absolute stability. An effective computational procedure is given, which is applicable to all cases when the existence of absolute stability may be established by this type of Liapunov’s function. Furthermore, the stability region in the parameter space is defined by the obtained conditions, the region of which contains that defined by the Popov frequency criterion.

关键词： absolute algebraic executive criterion Liapunov applicable independence arbitrary assume suppose

Molecular structure and biological function of proliferating cell nuclear antigen

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Progress in Natural Science:Materials International 2007年第10期17卷 1127-1135页

作者： Song Nanmeng1, Sang Jianli1 and Xu Heng2.1. Institute of Cell Biology, College of Life Science, Beijing normal university, Beijing 100875,{2. 2. Emory university school of Medicine, GA 30332. USA) Institute of Cell Biology College of Life Science Beijing Normal University Beijing 100875 China Emory university school of Medicine GA 30332 USA

Proliferating cell nuclear antigen (PCNA) is the core component of replication complex in eukaryote. As a processive factor of DNA polymerase delta, PCNA coordinates the replication process by interacting with various replication proteins. PCNA appears to play an essential role in many cell events, such as DNA damage repair, cell cycle regulation, and apoptosis, through the coordination or organization of different partners. PCNA is an essential factor in cell proliferation, and has clinical significance in tumor research. In this article we review the functional structure of PCNA, which acts as a function switch in different cell events.

关键词： PCNA Function Switch PCNA Binding Motif Cell Cycle DNA Replication DNA Repair.