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Epidemic dynamics on complex networks

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Progress in Natural science:Materials International 2006年第5期16卷 452-457页

作者： ZHOU Tao , FU Zhongqian, and WANG Binghong (department of Electronic science and technology, {3. of science and technology of China, hefei 230026, China department of modern physics, {3. of science and technology of China, hefei 230026, China) [a]department of Electronic science and technology University of Science and Technology of China Hefei China

Recently, motivated by the pioneer work in revealing the small-world effect and scale-free property of various real-life networks, many scientists devote themselves to studying complex networks. One of the ultimate goals is to understand how the topological structures affect the dynamics upon networks. In this paper, we give a brief review on the studies of epidemic dynamics on complex networks, including the description of classical epidemic models, the epidemic spread on small-world and scale-free networks, and network immunization. Finally, perspectives and some interesting problems are proposed.

关键词： epidemic dynamics complex networks critical value immunization small-world effect scale-free property.

Comparison study of trapped water in human erythrocytes by EPC and DSC method and its application

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science China(Technological sciences) 2004年第3期47卷 343-351页

作者： ZHAO Gang1, HE Liqun1, GUO Xiaojie2, LIU Zhong3. LUO Dawei1,3.& GAO Dayong1,3.1. Cryobiomedical Engineering Research Institute, department of Thermal science and Energy Engineering, university of science and technology of China, hefei 23.027, China 2. Red Cross Blood Center of hefei, hefei 23.022, China 3. department of Mechanical Engineering, university of Kentucky, Lexington, KY 40506-0108, USA Univ Sci & Technol China Cryobiomed Engn Res Inst Dept Thermal Sci & Energy Engn Hefei 230027 Peoples R China Red Cross Blood Ctr hefei Hefei 230022 Peoples R China Univ Kentucky Dept Mech Engn Lexington KY 40506 USA

The novel differential scanning calorimetry method for determining trapped water volume of human red blood cell during freezing process has been reexamined. Results show that the final erythrocyte volume is 53. of its isotonic volume after freezing to -40℃. An electronic particle counter (MultisizerTM III, Beckman Coulter Inc., USA) was used to measure cell volume changes in response to hypertonic solution. Using this approach, when extracellular solution was 3.86 mOsm, the equilibrium cell volume was found to be 57% of its isotonic value. Both results indicate that 3.%—40% of intracellular water is trapped and cannot respond to osmotic difference between intra- and extracellular solution. These findings are consistent with the published data: at least 20%—3.% of the isotonic cell water volume is retained within RBCs during freezing. Some applications of the values of trapped water are addressed.

关键词： differential scanning calorimeter/DSC, electronic particle counter/EPC, cell volumetric change, red blood cell/RBC/erythrocyte

A Note on Wigner Functions and *-Genvalue Equation

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Communications in Theoretical physics 2009年第4期51卷 605-608页

作者： JING Si-Cong LIN Bing-Sheng department of modern physics,{3. of science and technology of China,hefei 230026,China department of modern physics University of Science and Technology of China Hefei 230026 China

In deformation quantization,static Wigner functions obey functional *-genvalue equation,which is equiv-alent to time-independent Schr■dinger equation in Hilbert space operator formalism of quantum *** equiv-alence is proved mostly for Hamiltonian with form H=（1/2）■;+V（■）[***,***.60（1964）581].In this note we generalize this proof to a very general Hamiltonian H（■,■）and give examples to support it.

关键词： Wigner function *-genvalue equation deformation quantization

Characteristics of fMRI BOLD signal and its neurophysiological mechanism

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Progress in Natural science:Materials International 2007年第6期17卷 630-638页

作者： Zhao Xiaohu1,2, Wu Yigen3.and Guo Shengli3.1. College of Life sciences, Zhejiang university, Hangzhou 3.0058, China 2. Imaging department of Tongji Hospital of Tongji university, Shanghai 200065, China 3. College of Mathematics and physics, Nanjing university of Information science and technology, Nanjing 210044, China) College of Life sciences Zhejiang University Hangzhou 310058 China Imaging department Tongji Hospital Tongji University Shanghai 200065 China College of Mathematics and physics Nanjing University of Information Science and Technology Nanjing 210044 China

The functional magnetic resonance imaging (fMRI) based on blood oxygen level dependent (BOLD) contrast has emerged as one of the most potent noninvasive tools for mapping brain function and has been widely used to explore physiological, pathological changes and mental activity in the brain. Exploring the nature and property of BOLD signal has recently attracted more attentions. Despite that great progress has been made in investigation of the characteristics and neurophysiological basis, the exact nature of BOLD signal remains unclear. In this paper we discuss the characteristics of BOLD signals, the nonlinear BOLD response to external stimuli and the relation between BOLD signals and neural electrophysiological recordings. Furthermore, we develop our new opinions regarding nonlinear BOLD response and make some perspectives on future study.

关键词： functional magnetic resonance imaging blood oxygen level dependent nonlinear response neural electrophysiological activity.

Langevin Treatment of Atomic Coherence Effect on Hybrid Erbium doped Fiber Amplification

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Chinese Journal of Lasers 1999年第6期8卷 3-5页

作者： LIU Fangxin 1,3.GUO Yang 2 MING Hai 2 ( 1 Structure Research Laboratory, 2 department of physics, 3.department of Astronomy and Applied physics, university of science and technology of China, hefei 230026, China) 中国科学技术大学结构研究实验室结构分析开放实验室安徽合肥 230026 中国科学技术大学物理系安徽合肥

The effects of atomic coherence on hybrid erbium doped fiber amplifier (HEDFA) pumped simultaneously by two diode lasers with different frequencies are studied by using Langevin quantum theory. The expressions of coherence and incoherence gain are derived. The theoretical results show that HEDFA has a near flat bandwidth response from 153. to 1568 nm and large coherence gain under the conditions of low temperature and small detuning.

关键词： atomic coherence hybrid erbium doped fiber amplifier LD pump

Alterations in circadian rhythms of melaton in and cortisol in patients with bronchial asthma

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Acta Pharmacologica Sinica 2004年第5期25卷 109-114页

作者： Guang-he FEI2,3. Rong-yu LIU3.4, Zhi-hong ZHANG3. Jiang-ning ZHOU2,3.School of Life science, university of science and {3. of China, hefei 230026, China 3.ulmonary department, First Affiliated Hospital, Anhui Medical university, hefei 23.022, China School of Life science University of Science and Technology of China Hefei 230026 China

AIM: To investigate the possible relationships between alterations in circadian rhythm of melatonin, cortisol andbronchial asthma. METHODS: Salivary melatonin and cortisol were measured simultaneously by radioimmunoas-say in 10 mild intermittent or persistent patients, 11 moderate-to-severe persistent asthma patients, and 15 controlsubjects. Twelve salivary samples were collected in a series during a 24-h period in each subject. RESULTS: Theresults showed overall lower levels of salivary melatonin in asthma patients compared with control subject(P<0.01). The amplitude, peak-level, and baseline of salivary melatonin were significantly lower in mild intermit-tent or persistent (P<0.01, P<0.05) and moderate-to-severe persistent asthma patients (P<0.01) compared withcontrol group. The 24-h mean level of salivary cortisol was greatly lower and the acrophase was markedly delayedin patients with mild intermittent or persistent asthma (P<0.01) and moderate-to-severe persistent asthma (P<0.05, P<0.01) compared with control subject. CONCLUSION: Disordered circadian rhythms of salivary melato-nin and cortisol were found in asthma patients, which may be involved in the pathogenesis of bronchial asthma.

关键词： melatonin asthma circadian rhythm glucocorticoids human saliva

Formation of complexes of Rubisco-Rubisco activase from La^3., Ce^3. treatment spinach

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science China Chemistry 2005年第1期48卷 67-74页

作者： HONG Fashui1, LIU Chao1, ZHENG Lei1, WANG Xuefeng1, WU Kang1, SONG Weiping1, Lü Shipeng1, TAO Ye2 & ZHAO Guiwen3.1. College of Life sciences, Suzhou Universty, Suzhou 215006, China 2. Synchrotron Radiation Laboratory, Institute of High Energy physics, The Chinese Academy of science, Beijing 10003., China 3. Chemical {3., university of science and technology of China, hefei 230026, China 1. College of Life sciences Suzhou Universty 215006 Suzhou China 2. Synchrotron Radiation Laboratory Institute of High Energy Physics The Chinese Academy of Science 100039 Beijing China 3. Chemical department University of Science and Technology of China 230026 Hefei China

The complex of Rubisco and Rubisco activase from LaCl3., CeCl3. treated spinach in vivo is induced. SDS-PAGE result shows that the purified proteins from LaCl3., CeCl3. treated spinach have not only large and small subunits (55 kD, 14.4 kD) of Rubisco, but also two large subunits of 45 kD and 41 kD near the large subunits of Rubisco. Native-PAGE shows that the purified proteins from LaCl3., CeCl3. treated spinach have not only a band of Rubisco (560 kD), but also a band of about 1100 kD, about twice distant from Rubisco, which might be a complex of Rubisco and Rubisco activase. The purified enzyme activities from LaCl3., CeCl3.treated spinach are 1.8 and 2.8 times that of the control,the intensities of absorption and fluorescence are sig- nificantly higher than that of the purified Rubisco from the control, and the total sulfhydryl groups and available sulfhydryl groups are 3.—3. –SH per mol enzyme, 14—25 –SH per mol enzyme more than those of the purified Rubisco from the control, respectively. The CD spectra show that the secondary structure of the purified enzyme from LaCl3., CeCl3.-treated spinach is very dif- ferent from the control. The enzyme activities from LaCl3., CeCl3. treated spinach in vivo are 1.5 and 1.9 times those of the control.

关键词： La3., Ce3., spinach, Rubisco, complex of Rubisco and Rubisco acitivase, spectral characteristics.

X-ray spectra induced in highly charged 40Ar^q+ interacting with Au surface

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science China(physics,Mechanics & Astronomy) 2006年第2期49卷 203-212页

作者： ZHANG Xiao’an1,2, XIAO Guoqing1, YANG Zhihu1, CHEN Ximeng3. ZHAO Yongtao1, LI Fuli4, ZHANG Yinping1, CUI Ying3. ZHANG Hongqiang3. XU Xu3. SHAO Jianxiong3.& ZHAN Wenlong11. Institute of modern physics, Chinese Academy of sciences, Lanzhou 73.000, China 2. {3. of physics, Xianyang Normal university, Xianyang 712000, China 3. department of modern physics, Lanzhou university, Lanzhou 73.000, China 4. {3. of Applied physics, Xi’an Jiaotong university, Xi’an 710049, China 1. Institute of modern physics Chinese Academy of Sciences Lanzhou 730000 China 2. department of physics Xianyang Normal University Xianyang 712000 China 3. department of modern physics Lanzhou University Lanzhou 730000 China 4. department of Applied physics Xi’an Jiaotong University Xi’an 710049 China

By use of optical spectrum technology, the spectra of X-ray induced by highly charged 40Arq+ ions interacting with Au surface have been studied. The results show that the argon Kα X-ray were emitted from the hollow atoms formed below the surface. There is a process of multi-electron exciting in neutralization of the Ar16+ion, with electronic con-figuration 1s2 in its ground state below the solid surface. The yield of the projectile Kα X-ray is related to its initial electronic configuration, and the yield of the target X-ray is related to the projectile kinetic energy.

关键词： highly charged ion hollow multi-electron excitation X- ray.

Congruences on ideal nil-extension of completely regular semigroups

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Chinese science Bulletin 1998年第5期43卷 379-381页

作者： REN Xueming 1, 2 GUO Yuqi 2 and CEN Jiaping (Shum Kar-ping) 3.. department of Mathematics, Xi’an university of Architecture & technology, Xi’an 710055, China 2. department of Mathematics, Yunnan university, Kunming 650091, China 3. department of department of Mathematics Xi’an University of Architecture & Technology Xi’an China department of Mathematics Yunnan University Kunming China department of Mathematics Chinese University of Hong Kong Hong Kong

Let S be an ideal nil-extension of a completely regular semigroup K by a nil semigroup Q with zero. A concept of admissible congruence pairs (δ,ω) of S is introduced, where δ and ω are a congruence on Q and a congruence on K respectively. It is proved that every congruence on S can be uniquely respresented by an admissible congruence pair (δ,ω) of S. Suppose that ρ K denotes the Rees congruence induced by the ideal K of S. Then it is shown that for any congruence σ on S,a mapping Γ:σ|→(σ Q,σ K) is an order-preserving bijection from the set of all congruences on S onto the set of all admissible congruence pairs of S,where σ K is the restriction of σ to K and σ Q=(σ∨ρ K)/ρ K. Moreover,the lattice of congruences of S is also discussed. As a special case,every congruence on completely Archimedean semigroups S is described by an admissible quarterple of S. The following question is asked: Is the lattice of congruences of the completely Archimedean semigroup a semimodular lattice?

关键词： completely regular semigroups ideal nil-extension congruences.