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pH-Dependent Stability of EGX, A Multi-functional Cellulase from Mollusca, Ampullaria crossean

Acta Biochimica et Biophysica Sinica 2004年第9期36卷 603-608页

作者： Wen-Ying LI2, Ji WANG1, Yan-Hong LI1, Ming DING1, Gen-Jun XU1,3, Lan-Ying LIU2, and Fu-Kun ZHAO1,3* 1Key Laboratory of Proteomics, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological sciences, the Chinese Academy of sciences,Graduate School of the Chinese Academy of sciences, Shanghai 200031, china 2college of life science, jilin university, changchun 130023, china college of life science, Zhejiang university of science and Technology, Hangzhou 310018, china Key Laboratory ofProteomics Institute of Biochemistry and Cell BiologyShanghai Institutes for Biological Sciencesthe Chinese Academy of SciencesGraduate School of the Chinese Academy of SciencesShanghai 200031China

The cellulase activity and stability of EGX, a multi-functional cellulase previously purified from the mollusca Ampullaria crossean, was systematically studied under different pH. The pH induced con- formation and stability change of EGX have been investigated by using the intrinsic fluorescence, ANS fluorescence and CD spectrum. It has been found that the conformation and activity of this cellulase were strongly dependent on the pH. EGX was stable for both the enzyme activity and the conformation from pH 5.6 to pH 7.4. As shown by intrinsic and ANS fluorescence, no red shift of emission maximum occurred and a negligible intensity change was observed at pH 5.6–7.4. The activity of EGX remained about 80% in pH 5.6–7.4 and obviously decreased out of side the pH range. Urea-induced changes in EGX at pH 5.4 and pH 8.0 were measured by intrinsic fluorescence and CD spectrum. At pH 5.4, a significantly red shift of emission maximum occurred when the concentration of urea was 5 M compared to the concentration was 3 M at pH 8.0. The α-helix at pH 5.4 was 40.51% in the absence of urea and 31.04% in the presence of 4 M urea. At pH 8.0 the α-helix was 7.23% in the presence of 4 M urea. The data indicated that EGX was much susceptible to urea-induced unfolding at pH 8.0 and much stable at pH 5.4. The greater pH dependent stability of EGX may allow the enzyme to adequately catalyze the hydrolysis of cellulosic materials under natural or industrial extreme conditions.

关键词： multi-functional cellulase stability Ampullaria crossean fluorescence spectroscopy pH-dependent structural change CD spectrum

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Mitochondrial DNA analysis of ancient Sampula population in Xinjiang

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Progress in Natural science:Materials International 2007年第8期17卷 927-933页

作者： Xie Chengzhi~(1,2) Li Chunxiang~2 Cui Yinqiu~(1,2) Cai Dawei~(1,2) Wang Haijing~2 Zhu Hong~1 Zhou Hui~(1,2**) (1.Research Center for Chinese Frontier Archaeology,jilin university,changchun 130012,china 2.college of life science,jilin university,changchun 130023,china) [a]Research Center for Chinese Frontier Archaeology Jilin University Changchun China [b]college of life science Jilin University Changchun China

The archaeological site of Sampula cemetery was located about 14 km to the southwest of the Luo County in Xinjiang Khotan,china,belonging to the ancient Yutian kingdom.14C analysis showed that this cemetery was used from 217 *** 283 A.D. Ancient DNA was analyzed by 364 bp of the mitochondrial DNA hypervariable region I （mtDNA HVR-I）,and by six restriction fragment length polymorphism （RFLP） sites of mtDNA coding *** successfully extracted and sequenced intact stretches of maternally inher- ited mtDNA from 13 out of 16 ancient Sampula *** analysis of mtDNA haplogroup distribution showed that the ancient Sampula was a complex population with both European and Asian *** joining network of U3 sub-haplogroup and multi-dimen- sional scaling analysis all showed that the ancient Sampula had maternal relationship with Ossetian and Iranian.

关键词： ancient DNA mitochondrial DNA Sampula ancient populations

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Choice of Parameters in Morse Potential for Copper

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Journal of Materials science & Technology 1996年第6期12卷 473-475页

作者： Yuming WANG (Dept. of Materials science, jilin university changchun 130023, china) Dept. of Materials science Juin University Changchun 130023 China

The choice of parameters in Morse potential for copper was made by the molecular dynamics modeling. The elastic coefficients C-11, C-44, their temperature coefficients T-C11, T-C44, well as the hydrostatic compression behaviour, i.e. pressure/volume curves have been calculated. The choice of Morse potential parameters can be made by comparing the results with the experimental data. The chosen parameters are greatly different for different simulated properties.

关键词： Copper

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Mitochondrial DNA analysis of Bronze Age horses recovered from Chifeng region, Inner Mongolia, china

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Progress in Natural science:Materials International 2007年第5期17卷 544-550页

作者： Cai Dawei , Han Lu , Xie Chengzhi , Li Shengnan , Zhou Hui and Zhu Hong (Ancient DNA Laboratory, Research Center for Chinese Frontier Archaeology of jilin university, changchun 130023, china college of life science, jilin university, changchun 130023, china) [a]Ancient DNA Laboratory Research Center for Chinese Frontier Archaeology of Jilin University Changchun China [b]college of life science Jilin University Changchun China

In this study, mitochondrial DNA (mtDNA) analysis was carried out on 9 Bronze Age horses recovered from Dashanqian and Jinggouzi archaeological sites in Chifeng region, Inner Mongolia. china to explore the origin of Chinese domestic horses. Both mtDNA 16S rRNA gene and control region (D-loop) fragments of ancient horses were amplified and sequenced. The analysis of the highly conservative 16S rRNA gene sequences indicated that the burial environment of Chifeng region is suitable for the preservation of ancient DNA (aDNA). Combing 465 mtDNA D-loop sequences representing different breeds from East Asia, Central Asia, Near East and Europe, we constructed a phylogenetic network to investigate the relationship between ancient and modern horses. The phylogenetic network showed that the 9 horses were distributed into different modern horse clusters which were closely related to them representing a certain geographical distribution. Our results showed that the maternal genetic line of the ancient horses in Chifeng region was highly diversified, which contributed to the gene pool of modern domestic horses and suggested a complex origin of domestic horses in china.

关键词： origin of domestic horses ancient DNA mitochondrial DNA 16S rRNA gene phylogenetic network.

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Sub-Nyquist sampling-based wideband spectrum sensing:a compressed power spectrum estimation approach

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Frontiers of Computer science 2024年第2期18卷 139-145页

作者： jilin WANG Yinsen HUANG Bin WANG National Key Laboratory of science and Technology on Communications University of Electronic Science and Technology of ChinaChengdu 611731China

In this paper,we introduce a sub-Nyquist sampling-based receiver architecture and method for wideband spectrum *** of recovering the original wideband analog signal,the proposed method aims to directly reconstruct the power spectrum of the wideband analog signal from sub-Nyquist *** that power spectrum alone is sufficient for wideband spectrum *** only the covariance matrix of the wideband signal is needed,the proposed method,unlike compressed sensing-based methods,does not need to impose any sparsity requirement on the frequency *** proposed method is based on a multi-coset sampling *** exploiting the inherent sampling structure,a fast compressed power spectrum estimation method whose primary computational task consists of fast Fourier transform(FFT)is *** results are presented to show the effectiveness of the proposed method.

关键词： wideband spectrum sensing sub-Nyquist multicoset sampling FCPSE

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Towards advanced zinc anodes by interfacial modification strategies for efficient aqueous zinc metal batteries

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Journal of Energy Chemistry 2024年第6期93卷 79-110,I0003页

作者： changchun Fan Weijia Meng Jiaye Ye Key Laboratory of Bio-Inspired Smart Interfacial science and Technology Ministry of EducationSchool of ChemistryBeihang UniversityBeijing 100191China Shaanxi Key Laboratory of New Transportation Energy and Automotive Energy Saving School of Energy and Electrical EngineeringChang’an UniversityXi’an 710061ShaanxiChina School of Chemistry and Physics Faculty of ScienceQueensland University of TechnologyBrisbaneQLD 4001Australia Centre for Materials science Queensland University of TechnologyBrisbaneQLD 4001Australia

Developing sustainable and clean energy sources(e.g.,solar,wind,and tide energy)is essential to achieve the goal of carbon *** to the discontinuous and inco nsistent nature of common clean energy sources,high-performance energy storage technologies are a critical part of achieving this *** zinc metal batteries(AZMBs)with inherent safety,low cost,and competitive performance are regarded as one of the promising candidates for grid-scale energy ***,zinc metal anodes(ZMAs)with irreversible problems of dendrite growth,hydrogen evolution reaction,self-corrosio n,and other side reactions have seriously hindered the development and commercialization of *** increasing number of researchers are focusing on the stability of ZMAs,so assessing the effectiveness of existing research strategies is critical to the development of *** review aims to provide a comprehensive overview of the fundamentals and challenges of *** rch strategies for interfacial modification of ZMAs are systematically *** features of artificial interfacial coating and in-situ interfacial coating of ZMAs are compared and discussed in detail,as well as the effect of modified interfacial ZMA on the full-battery ***,perspectives are provided on the problems and challenges of *** review is expected to offer a constructive reference for the further development and commercialization of AZMBs.

关键词： Aqueous zinc metal batteries Zinc metal anode Interfacial modification Artificial interfacial coating In-situ interfacial coating

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Properties of meso-tetrakis (4-n-alkanoyloxyphenyl) porphyrin liquid crystal Co and Ni complexes

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science china Chemistry 2007年第4期50卷 488-493页

作者： LIU Wei1,2 & SHI TongShun2 1 college of Materials science and Engineering, Shandong university of Technology, Zibo 255049, china 2 Department of Chemistry, jilin university, changchun 130023, china 1. college of Materials science and Engineering Shandong University of Technology Zibo 255049 China 2. Department of Chemistry Jilin University Changchun 130023 China

Six series of meso-tetrakis (4-n-alkanoyloxyphenyl) porphyrin Co and Ni complexes (12 kinds) were reported. Nine of the compounds were found to exhibit liquid crystal properties and display a hexagonal columnar discotic columnar (Colh) phase. Molecular structure of all synthesized compounds was confirmed by IR, UV, MS, 1H NIVR, and elemental analysis. These liquid crystalline compounds have been studied by cyclic voltammetry, luminescence, and surface photovoltage spectroscopy.

关键词： porphyrin liquid crystal cyclic voltammetry luminescence surface photovoltage spectroscopy

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Molecular biological analysis of remains from Jiangjungou Cemetery in Inner Mongolia

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Progress in Natural science:Materials International 2006年第7期16卷 727-731页

作者： WANG Haijing, LIU Weiqiang, FU Yuqin, ZHANG Xiaolei, ZHOU Hui and ZHU Hong ( Research Center for Chinese Frontier Archaeology of jilin university, changchun 130012, china college of Chemistry, jilin university, changchun 130023, china college of life science, jilin university, changchun 130023, china) [a]Research Center for Chinese Frontier Archaeology of jilin university Changchun China [b]college of Chemistry Jilin University Changchun China [c]college of life science Jilin University Changchun China

The 364-bp nucleotide sequence in hypervariable region I (HVRI) of mitochondrial DNA is successfully amplified from 9 out of 11 individuals of an ancient population buried in the Jiangjungou Cemetery in Inner Mongolia dated back to the Warring States Period in china. Nine fragments with different variations are obtained. A phylogenetic tree and a multidimensional scaling (MDS) plot are constructed using mtDNA sequences from the ancient population and several modern Asian populations. The results show that ancient population shares a closer genetic relationship with East Asian populations than with North and Central Asian populations. The genetic and historical evidence raise the possibility that the population might be the immigrants from Zhongyuan area, sent by the King Wuling of Zhao State to guard the nation against the attack from Huns.

关键词： mtDNA genetic relationship ancient DNA population.

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Quantifying quantum entanglement via machine learning models

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Communications in Theoretical Physics 2024年第7期76卷 52-56页

作者： changchun Feng Lin Chen LMIB(Beihang university) Ministry of EducationBeijing 100191China School of Mathematical sciences Beihang UniversityBeijing 100191China International Research Institute for Multidisciplinary science Beihang UniversityBeijing 00191China

Quantifying entanglement measures for quantum states with unknown density matrices is a challenging *** learning offers a new perspective to address this *** training machine learning models using experimentally measurable data,we can predict the target entanglement *** this study,we compare various machine learning models and find that the linear regression and stack models perform better than *** investigate the model's impact on quantum states across different dimensions and find that higher-dimensional quantum states yield better ***,we investigate which measurable data has better predictive power for target entanglement *** correlation analysis and principal component analysis,we demonstrate that quantum moments exhibit a stronger correlation with coherent information among these data features.

关键词： quantum information entanglement predict machine learning coherence

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Finite-time composite learning control for nonlinear teleoperation systems under networked time-varying delays

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science china(Information sciences) 2024年第6期67卷 279-296页

作者： Yana YANG Huixin JIANG changchun HUA Junpeng LI Institute of Electrical Engineering Yanshan University

The robust finite-time synchronization control problem is investigated for master-slave networked nonlinear telerobotics systems(NNTSs) in this article. Although there have been some research achievements on finite-time control for the NNTSs, these studies are based on the strong assumptions of communication time delays or can only achieve finite-time bounded convergence even when the external forces are *** and in view of the importance of these issues, a novel robust composite learning adaptive control scheme rendering the finite-time master-slave synchronization is proposed in this paper. In particular, the influence of time delays on finite-time convergence of the system is analyzed by employing the multi-dimension finite-time small-gain framework. Meanwhile, in order to achieve accurate and fast estimation of uncertain parameters of the system, both the online historical and the instantaneous data of the estimation data are explored to derive the new parameter adaptive law under a more realizable interval-excitation(IE) ***, the convergence of the position/force synchronization errors and the adaptive parameter estimation errors is obtained in finite time, and enhanced robustness of the closed-loop system will also be ***, the superior performance of the proposed control algorithms is validated by numerical simulations and hardware experiments.

关键词： networked teleoperation systems finite-time control exact parameter estimation small-gain theorem unknown communication delays

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