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Neuroglobin mutation associated with hypoxia adaptation in Tibet chicken

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Progress in natural Science:Materials International 2007年第12期17卷 1419-1424页

作者： Zhang Lifan1, Liu Chong2, Lian Linsheng3, Zhao Chunjiang1, Bao Haigang1 and Wu Changxin1(1. College of Animal Science and technology, china Agricultural university, beijing 100094, china 2. College of Biological Science, china Agricultural university, beijing 100094, china 3. College of Animal Science and technology, Yunnan Agricultural university, Kunming 650201, china) College of Animal Science and technology China Agricultural University Beijing 100094 China College of Biological Science China Agricultural University Beijing 100094 China College of Animal Science and technology Yunnan Agricultural University Kunming 650201 China

Globin protein family plays an important role in storing and transporting oxygen. As a newly reported globin, the revealed function of neuroglobin includes binding and storing oxygen as well as facilitating the utilization of oxygen in neuronal cells. In the present study, mutations in exons of chicken Ngb gene were identified with the method of sequencing and created restriction site PCR in Tibet chicken and other four lowland chicken breeds. The mutations of Lys-2224(E4)-Asn and Ser-2279(E4)-Gly were identified in exon 4 of the gene. The Lys-2224(E4)-Asn mutation existed only in Tibet chicken and the mutation frequencies increased with increasing altitude. Analysis of the haplotype and diplotype of the two mutations in Tibet chicken populations of different altitudes showed that the frequencies of TG haplotype and TTGG diplotype also increased with increasing altitude, while the reverse tendency was found on GGAA diplotype. Under the hypoxic simulation incubation, the main haplotype was TG in living embryos and GA in dead embryos. The results showed that the Lys-2224(E4)-Asn mutation may be a specific mutation associated with hypoxia adaptation in Tibet chicken.

关键词： Tibet chicken neuroglobin hypoxia adaptation Ngb gene mutation.

Transitivity, mixing and chaos for a class of set-valued mappings

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Science china Mathematics 2006年第1期49卷 1-8页

作者： LIAO Gongfu, WANG Lidong & ZHANG Yucheng Institute of Mathematics, Jilin university, Changchun 130012, china Institute of Nonlinear information technology, Dalian Nations university, Dalian 116600, china Department of Mathematics, university of Science and technology of china, Hefei 230026, china Institute of Mathematics Jilin University Changchun China Institute of Nonlinear information technology Dalian Nations University Dalian China Department of Mathematics University of Science and Technology of China Hefei China

Consider the continuous map f : x → X and the continuous map f of K,(X) into itself induced by f, where X is a metric space and K(X) the space of all non-empty compact subsets of x endowed with the Hausdorff metric. According to the questions whether the chaoticity of f implies the chaoticity of f posed by Roman-Flores and when the chaoticity of f implies the chaoticity of f posed by Fedeli, we investigate the relations between f and f in the related dynamical properties such as transitivity, weakly mixing and mixing, etc. And by using the obtained results, we give the satisfied answers to Roman-Flores's question and Fedeli's question.

关键词： set-valued mapping, transitivity, weak mixing, mixing, chaos.

The band structures of BSb and B_xGa_(1-x)Sb alloys

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Science china(Physics,Mechanics & Astronomy) 2009年第6期52卷 843-847页

作者： XIONG DePing1, ZHOU ShouLi2, WANG Qi3, LUO Li1, HUANG YongQing3 & REN XiaoMin3 1 School of Physics and Optoelectronic Engineering, Guangdong university of technology, Guangzhou 510006, china 2 College of information Engineering, Zhejiang university of technology, Hangzhou 310032, china 3 Key Laboratory of Optical Communication and Lightwave Technologies Ministry of Education, beijing university of Posts and Telecommunications, beijing 100876, china School of Physics and Optoelectronic Engineering Guangdong University of Technology Guangzhou China College of information Engineering Zhejiang University of Technology Hangzhou China Key Laboratory of Optical Communication and Lightwave Technologies Ministry of Education Beijing University of Posts and Telecommunications Beijing China

The band structures of BSb and BxGa1-xSb alloys are studied using first-principles calculations in the generalized gradient approximation. By SQS-8 supercells to model a random alloy, the direct transition energy-gap (Γ15v- Γ1c) bowing of 3.0 eV is obtained for BxGa1-xSb alloys in x = 0-50%, in x = 0-11% the energy-gap is the band-gap and increases by 7 meV/%B with boron composition increasing; by SQS-16 supercells the bowing parameter is about 1.9 eV in x = 0-12.5%. The formation enthalpies of mixing, ΔH, are calculated for BxGa1-xAs and BxGa1-xSb alloys. A comparison of enthalpies indicates that BxGa1-xSb films with boron composition of 7% may be possible.

关键词： band-gap bowing parameter boride alloys

Transport network and flow mechanism of shallow ore-bearing magma in Tongling ore cluster area

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Science china Earth Sciences 2006年第4期49卷 397-407页

作者： DENG Jun1,2, WANG Qingfei1,2 , HUANG Dinghua3 , WAN Li4, YANG Liqiang1,2 & GAO Bangfei1,2 1. State Key Laboratory of Geological Processes and Mineral resources, china university of Geosciences, beijing 100083, china 2. Key Laboratory of Lithosphere Tectonics and Lithoprobing technology of Ministry of Education, china university of Geo- sciences, beijing 100083, china 3. Faculty of Earth Sciences, china university of Geosciences, Wuhan 430074, china 4. School of Mathematics and information Science, Guangzhou university, Guangzhou 510405, china State Key Laboratory of Geological Processes and Mineral resources China University of Geosciences Beijing China Key Laboratory of Lithosphere Tectonics and Lithoprobing technology of Ministry of Education China University of Geosciences Beijing China Faculty of Earth Sciences China University of Geosciences Wuhan China School of Mathematics and information Science Guangzhou University Guangzhou China

Abundant studies revealed that shallow intrusions of the Yanshanian epoch resulted in the mass mineralization of the Tongling region. Various evidences showed there existed a concealed magma chamber at ?10 km depth in the middle part of this region during Yanshanian epoch, from which the ore-forming magma was generated and then transported to the superficial layer. Yet the transport network and flow mechanism of the shallow ore-bearing magma, the key problem associ- ated with ore-forming process, was relatively little focused on. Integrate analysis of structural me- chanics, statistical fractal and geological facts suggested that NE trending high-angle fold-related thrust faults and the tessellated basement ones served as the main pathways for the shallow magma’s transporting, moreover, the saddle void spaces among adjacent strata in the folds upon this fault system provided the place for magma’s emplacement. So the folds in the upper part and faults in the lower part of the upper crust constituted the fluid’s transport and emplacement network. During the deformation of geologic body with multi-layer structure, the layers in the upper part tended to fold when received the jacking stress from the lower part, while the lower one inclined to fault undergoing loads of the upper part. And the producing probability of this structure assemblage was highly in- creased in the condition, such as in the Tongling area, that the mechanic rigidity of the lower layers was stronger than that of the upper ones. For the pre-existence of fluid-conducting network, the top magma with high volatile in the magma chamber transported rapidly to the superficial layer in dyking pattern, located in the void spaces of folds, filled and reconstructed them. The sudden drop of pres- sure caused the fluid unmixing from the magma and mass ore-forming elements concentration. Pulse activity of the dyking may be the principal reason why magmatic bodies in the Tongling area were spatially-temporally con

关键词： Tongling, structural network, magma intrusion, fractal, dyke.

The role of aerial algae in the formation of the landscape of the Yunnan Stone Forest,Yunnan Province, china

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Science china Earth Sciences 2004年第9期47卷 846-864页

作者： TIAN Youping1,3, ZHANG Jie2, SONG Linhua1 & BAO Haosheng2 1. Institute of Geographic Sciences and natural resources Research, Chinese Academy of Sciences, beijing 100101, china 2. Department of Geography, Nanjing university, Nanjing 210093, china 3. School of Earth Sciences and resources, china university of Geosciences, beijing 100083, china Institute of Geographic Sciences and natural resources Research Chinese Academy of Sciences Beijing China School of Earth Sciences and resources China University of Geosciences Beijing China Department of Geography Nanjing University Nanjing China

Aerial algae on the surface of carbonate rocks at the Stone Forest, Shilin County, Yunnan Province, china, and their bioerosion were investigated in the field and studied in the laboratory in detail. Through the observation, identification and statistics of more than one hun- dred algal samples and rock samples with the optical microscopes (stereomicroscope, biological microscope) and the scanning electronic microscope (SEM), the relationships between erosional forms on the surface of the Stone Forest and algae and/or algal communities and the genetic mechanism for the formation of erosional forms were analyzed. It is suggested that aerial algae play an active role in bioerosive processes that may affect the formation of karst erosional forms. These effects include both direct and indirect ones. The direct effect is the initiative control (algal shape-controlling role) of algae on the formation of karst forms of various scales, mostly mi- cro-scale (3m) and minor-scale (10-3-10-1m) erosional forms. The algal shape-controlling roles can be divided into the algal individual shape-controlling role and the algal community shape-controlling role. The former mostly controls the formation of micro-scale erosional forms, while the latter mostly controls the formation of micro-scale and smaller minor-scale erosional forms. The indirect effect refers to the promoting role of algae in the formation of karst forms, which may affect the formation of karst forms of all types and scales. The bioerosion of algae accelerates the weathering process of the whole Stone Forest karst landforms.

关键词： aerial algae, bioerosion, the Stone Forest, Yunnan Province, china.

Two mode photon bunching effect as witness of quantum criticality in circuit QED

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Science china(Physics,Mechanics & Astronomy) 2009年第12期52卷 1898-1905页

作者： AI Qing1,WANG YingDan2,LONG GuiLu1,3 & SUN ChangPu4 1 Department of Physics,Tsinghua university,beijing 100084,china 2 Department of Physics,university of Basel,Klingelbergstrasse 82,4056 Basel,Switzerland 3 Tsinghua National Laboratory for information Science and technology,beijing 100084,china 4 Institute of Theoretical Physics,Chinese Academy of Sciences,beijing 100080,china Department of Physics Tsinghua University Beijing China Department of Physics University of Basel Basel Switzerland Tsinghua National Laboratory for information Science and technology Beijing China Institute of Theoretical Physics Chinese Academy of Sciences Beijing China

We suggest a scheme to probe critical phenomena at a quantum phase transition (QPT) using the quantum correlation of two photonic modes simultaneously coupled to a critical system. As an experimentally accessible physical implementation,a circuit QED system is formed by a capacitively coupled Josephson junction qubit array interacting with one superconducting transmission line resonator (TLR). It realizes an Ising chain in the transverse field (ICTF) which interacts with the two magnetic modes propagating in the TLR. We demonstrate that in the vicinity of criticality the originally independent fields tend to display photon bunching effects due to their interaction with the ICTF. Thus,the occurrence of the QPT is reflected by the quantum characteristics of the photonic fields.

关键词： quantum phase transition photon bunching circuit QED

Design of secure operating systems with high security levels

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Science in china(Series F) 2007年第3期50卷 399-418页

作者： QING SiHan1,2 & SHEN ChangXiang3 1 Institute of Software, Chinese Academy of Sciences, beijing 100080, china 2 School of Software and Microelectronics, Peking university, beijing 102600, china 3 Institute of Computing technology, Navy, beijing 100841, china Institute of Software Chinese Academy of Sciences Beijing China School of Software and Microelectronics Peking University Beijing China Institute of Computing technology Navy Beijing China

Numerous Internet security incidents have shown that support from secure operating systems is paramount to fighting threats posed by modern computing environments. Based on the requirements of the relevant national and international standards and criteria, in combination with our experience in the design and development of the ANSHENG v4.0 secure operating system with high security level （hereafter simply referred to as ANSHENG OS）, this paper addresses the following key issues in the design of secure operating systems with high security levels： security architecture, security policy models, and covert channel analysis. The design principles of security architecture and three basic security models： confidentiality, integrity, and privilege control models are discussed, respectively. Three novel security models and new security architecture are proposed. The prominent features of these proposals, as well as their applications to the ANSHENG OS, are elaborated. Cover channel analysis （CCA） is a well-known hard problem in the design of secure operating systems with high security levels since to date it lacks a sound theoretical basis and systematic analysis approach. In order to resolve the fundamental difficulties of CCA, we have set up a sound theoretical basis for completeness of covert channel identification and have proposed a unified framework for covert channel identification and an efficient backward tracking search method. The successful application of our new proposals to the ANSHENG OS has shown that it can help ease and speedup the entire CCA process.

关键词： secure operating systems with high security levels architecture security model covert channel analysis

An improved method for evaluating the seasonal variability of total suspended sediment flux field in the Yellow and East china Seas

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International Journal of Sediment Research 2011年第1期26卷 1-14页

The suspended sediment flux field in the Yellow and East china Seas(YECS) displays its seasonal variability.A new method is introduced in this paper to obtain the flux field via retrieval of ocean color remote sensing data,statistical analysis of historical suspended sediment concentration data,and numerical simulation of three-dimensional(3D) flow *** components of the sediment flux field include(i) surface suspended sediment concentration inverted from ocean color remote sensing data;(ii) vertical distribution of suspended sediment concentration obtained by statistical analysis of historical observation data;and(iii) 3D flow field modeled by a numerical *** the improved method,the 3D suspended sediment flux field in the YECS has been *** comparison with the suspended sediment flux field solely based on the numerical simulation of a suspended sediment transport model,the suspended sediment flux field obtained by the improved method is found to be more *** 3D suspended sediment flux field from ocean colour remote sensing and in situ observation are more closer to the ***,by quantitatively analyzing the newly obtained suspended sediment flux field,the quantity of sediment erosion and deposition within the different regions can be *** sediment exchange between the Yellow Sea and the East china Sea can be *** mechanism of suspended sediment transport in the YECS can be better *** particular,it is suggested that the long-term transport of suspended sediment is controlled mainly by the circulation pattern,especially the current in winter.

关键词： Suspended sediment flux field Seasonal variability Yellow and East china Seas Regression equation Numerical simulation

Lp（ [0, 1]）-characterizations of multi-knot piecewise linear spectral sequences

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Progress in natural Science:Materials International 2006年第7期16卷 684-690页

作者： LIAN Qiaofang, CHENG Linfeng, and YAN Dunyan ( Department of Mathematics, beijing Jiaotong university, beijing 100044, china Department of Mathematics, china university of Mining and technology, Xuzhou 221008, china School of information Science and Engineering, Graduate university of Chinese Academy of Sciences, beijing 100080, china) Chinese Acad Sci Sch Informat Sci & Engn Beijing 100080 Peoples R China china Univ Min & Technol Xuzhou 221008 Peoples R China beijing Jiaotong Univ Dept Math Beijing 100044 Peoples R China

There exists a class of new orthonormal basis for L2([0, 1]), whose exponential parts are multi-knot piecewisf linear functions called spectral sequences. In this paper, we show that these bases constitute bases, but not unconditional bases, for Lp([0, 1 ]) with 1更多还原AbstractFilter('ChDivSummary', 'ChDivSummaryMore', 'ChDivSummaryReset');

关键词： exponential bases multi-knot piecewise linear spectral sequences unconditional bases.