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Acta Biochimica et Biophysica Sinica 2004年第7期36卷 513-517页

作者： Lei FANG, Qi-Ming SUN, and Zi-Chun HUA*The State Key Laboratory of Pharmaceutical Biotechnology, nanjing university, nanjing 210093, china The State Key Laboratory of Pharmaceutical Biotechnology Nanjing University Nanjing 210093 China

Enterokinase is a tool protease widely utilized in the cleavage of recombinant fusion proteins. cDNA encoding the catalytic subunit of Chinese bovine enterokinase (EKL) was amplified by PCR and then fused to the 3′ end of prepro secretion signal peptide gene of α-mating factor from Saccharomyces cerevisiae to get the α-MF signal-EKL-His6 encoding gene by PCR. Then the whole coding sequence was cloned into the integrative plasmid pAO815 under the control of a methanol-inducible promoter and transformed GS115 methylotrophic strain of Pichia pastoris. Secreted expression of recombinant EKL-His6 was attained by methanol induction and its molecular weight is 43 kD. Because of the existence of His6-tag, EKL-His6 was easily purified from P. pastoris fermentation supernatant by using Ni2+ affinity chromatography and the yield is 5.4 mg per liter of fermentation culture. This purified EKL-His6 demonstrates excellent cleavage activity towards fusion protein containing EK cleavage site.

关键词： recombinant enterokinase secreted expression Ni2+ affinity chromatography fusion protein cleavage

More on Bounding Introspection in Modal Nonmonotonic Logics

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Acta Mathematica Sinica,English Series 2000年第4期16卷 555-564页

作者： Xishun Zhao Decheng Ding Department of Mathematics. nanjing university. nanjing 210093, P. R. china Department of Mathematics Nanjing University Nanjing 210093 P. R. China

By L. we denote the set of all propositional fornmlas. Let C be the set of all clauses. Define C_n=C(Lη:η∈C}.In Sec. 2 of this paper. we prove that for normal modal logics S, the notions of (S. C_)-expansions and S-expansions coincide. In Sec. 3. we prove that if I consists of default clauses then the notions of S-expansions for I and (S.C)-expansions for I coincide. To this end. we first show. in Sec *** the notion of S-expansions for I is the same as that of (S.L)-expansions for I.

关键词： Modal nonmonotonic logic Expansion Bounding Introspection Default clause

A new frequency scale of Chinese whispered speech in the application of speaker identification

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Progress in Natural Science:Materials International 2006年第10期16卷 1072-1078页

作者： LIN Wei, YANG Lili and XU Boling (Institute of Acoustics & Key Laboratory of Modern Acoustics, nanjing university, nanjing 210093, china) Institute of Acoustics and Key Laboratory of Modern Acoustics Nanjing University Nanjing 210093 China

In this paper, the frequency characteristics of Chinese whispered speech were investigated by a filter bank analysis. It was shown that the first and the third formants were more important than the other formants in the speaker identification of Chinese whispered speech. The experiment showed that the 800-1200 Hz and 2800-3200 Hz ranges were the most significant frequency ranges in discriminating the speaker. Based on this result, a new feature scale named whisper sensitive scale (WSS) was proposed to replace the common scale, Mel scale, and to extract the cepstral coefficient from whispered speech signal. Furthermore, a speaker identification system in whispered speech was presented based on the modified Hidden Markov Models integrating advantages of WSCC (the whisper sensitive cepstral coefficient) and LPCC. And the new system performed better in solving the problem of speaker identification of Chinese whispered speech than the traditional method.

关键词： speaker identification Chinese whispered speech whisper sensitive scale.

MEASUREMENT OF NUMBER AVERAGE MOLECULAR WEIGHT OF STYRENE OLIGOMER BY ^(13)C-NMR METHOD

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Chinese Journal of Polymer Science 1999年第2期17卷 135-140页

作者： Song Wang Xiao-hu Yan Rong-shi Cheng Department of Polymer Science and Engineering, nanjing university, nanjing 210093, china Department of Polymer Science and Engineering Nanjing University Nanjing 210093 China

^(13)C-NMR ~1H-decoupled spectra of styrene polymers were assigned by comparison with modelcompounds, then used in measurements of number average molecular weights. The higher limit of an exactdetermination of the end group signal is less than a molecular weight of 10~4. For polymer samples withM_n3, the results obtained from ^(13)C-NMR spectra of saturated carbon region are in excellent agreementwith the values determined by ~1H-NMR, SEC, and VPO methods, while the results from ^(13)C-NMR spectra ofphenyl C-1 carbon region are somewhat higher than the values determined by other methods.

关键词： Molecular weight measurement Styrene oligomer ^(13)C-NMR spectra

Maschke-type theorem and Morita context over weak Hopf algebras

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Science china Mathematics 2006年第5期49卷 587-598页

作者： ZHANG Liangyun College of Science, nanjing Agricultural university, nanjing 210095, china Department of Mathematics, nanjing university, nanjing 210008, china College of Science Nanjing Agricultural University Nanjing China Department of Mathematics Nanjing University Nanjing China

This paper gives a Maschke-type theorem over semisimple weak Hopf algebras,extends the well-known Maschke-type theorem given by Cohen and Fishman and constructs a Morita context over weak Hopf algebras.

关键词： weak Hopf algebra, smash product, Maschke-type theorem, Morita context.

An effective absorbing boundary algorithm for acoustical wave propagator

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Progress in Natural Science:Materials International 2007年第9期17卷 1012-1017页

作者： Lin Zhibin ,Lu Jing and Xu Boling(Key Laboratory of Modern Acoustics,Institute of Acoustics,nanjing university,nanjing 210093,china) Key Laboratory of Modern Acoustics Institute of Acoustics Nanjing University Nanjing 210093 China

In this paper,Berenger’s perfectly matched layer(PML)absorbing boundary condition for electromagnetic waves is introduced as the truncation area of the computational domain to absorb one-dimensional acoustic wave for the scheme of acoustical wave propagator(AWP).To guarantee the efficiency of the AWP algorithm,a regulated propagator matrix is derived in the PML *** simulations of a Gaussian wave packet propagating in one-dimensional duct are carried out to illustrate the efficiency of the combination of PML and *** with the traditional smoothing truncation windows technique of AWP,this scheme shows high computational accuracy in absorbing acoustic wave when the acoustical wave arrives at the computational *** coefficients of the PML configurations are also discussed.

关键词： acoustical wave propagator perfectly matched layer absorbing boundary conditions(ABC).

The Origin of Infrared Emission from the Infrared Luminous Galaxy NGC 4418

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Chinese Journal of Astronomy and Astrophysics 2005年第2期5卷 117-125页

作者： Lei Shi and Qiu-Sheng Gu Department of Astronomy, nanjing university, nanjing 210093 qsgu@*** Department of Astronomy Nanjing University Nanjing 210093

We present a study of the origin of infrared (IR) emission in the opticallynormal, infrared luminous galaxy NGC 4418. By decomposing the stellar absorption features andcontinua in the range of 3600-8000 A from the Sloan Digital Sky Survey into a set of simple stellarpopulations, we derive the stellar properties for the nuclear region of NGC 4418. We compare theobserved infrared luminosity with the one derived from the starburst model, and find thatstar-forming activity contributes only 7% to the total IR emission, that as the IR emission regionis spatially very compact, the most possible source for the greater part of the IR emission is adeeply embedded AGN, though an AGN component is found to be unnecessary for fitting the opticalspectrum.

关键词： galaxies: general galaxies: active galaxies: stellar content galaxies:individual (NGC 4418)

Reducing component estimation for varying coefficient models with longitudinal data

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Science china Mathematics 2008年第2期51卷 250-272页

作者： TANG QingGuo~(1,2+) WANG JinDe~2 1 Institute of Sciences,People’s Liberation Army university of Science and Technology,nanjing 210007,china 2 Department of Mathematics,nanjing university,nanjing 210093,china Institute of Sciences People’s Liberation Army University of Science and Technology Nanjing China Department of Mathematics Nanjing University Nanjing China

Varying-coefficient models with longitudinal observations are very useful in epidemiology and some other practical *** this paper,a reducing component procedure is proposed for es- timating the unknown functions and their derivatives in very general models,in which the unknown coefficient functions admit different or the same degrees of smoothness and the covariates can be time- *** asymptotic properties of the estimators,such as consistency,rate of convergence and asymptotic distribution,are *** asymptotic results show that the asymptotic variance of the reducing component estimators is smaller than that of the existing estimators when the coefficient functions admit different degrees of *** sample properties of our procedures are studied through Monte Carlo simulations.

关键词： varying coefficient model longitudinal data nonparametric estimation reducing component estimators asymptotic normality 62G07

Afterglow from GRB 070610/Swift J195509.6+261406:An explanation using the fireball model

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Science china(Physics,Mechanics & Astronomy) 2010年第S1期53卷 94-97页

作者： KONG SiWei & HUANG YongFeng Department of Astronomy,nanjing university,nanjing 210093,china Department of Astronomy Nanjing University Nanjing China

GRB 070610,which is also named Swift J195509.6+261406,is a peculiar Galactic transient with significant variability on short timescales in both X-ray and optical light *** possible explanation is that GRB 070610/Swift J195509.6 + 261406 is a soft gamma-ray repeater(SGR) in our ***,we use the fireball model,which is usually recognized as the standard model of gamma-ray burst(GRB) afterglows,and the energy injection hypothesis to interpret the X-ray and optical afterglow light curves of GRB 070610/Swift J195509.6 + *** is found that the model is generally consistent with observations.

关键词： gamma-ray bursts soft gamma-ray repeaters outflows

Magnetic fabrics in fault-related fold and its relation with finite strain: an example from Mingjiang thrust structures in Western Sichuan

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Progress in Natural Science:Materials International 2007年第5期17卷 551-558页

作者： Jia Dong, Chen Zhuxin, Luo Liang, Hu Qianwei and Jia Qiupeng (Department of Earth Sciences, nanjing university, nanjing 210093, china) Department of Earth Sciences Nanjing University Nanjing 210093 China

The anisotropy of magnetic susceptibility (AMS) is a quick, effective and sensitive technique used to measure the weakly deformed sedimentary rocks, and also a reliable method to reveal the deforming mechanisms of fault-related folds. In Longmenshan front belt, a typical cross-section of fault-related folds is chosen to study the AMS. A total of 224 oriented specimens have been drilled at 23 different sampling sites which were distributed at the key structural positions of this structural section developed in the Xujiahe formation of the upper Triassic. Six elementary types of magnetic fabrics are recognized and established through this AMS study: Da sedimentary fabric; 2) an initial deformation fabric; 3) a pencil structure fabric; 4) a weak cleavage fabric; 5) a strong cleavage fabric; 6) a stretching lineation fabric. It has been found that most of magnetic fabrics are characterized by fabrics of weak deformation which belong to the pure-shear results of a pre-folding layer parallel shortening (LPS). In the fault-bend fold, almost all magnetic fabrics are the initial deformation fabrics of weak deformation, and denote that the deformation in the forelimb is stronger than that in the backlimb and no finite strain is shown in the footwall. While in the fault-propagation fold, finite strains are concentrated in the trishear zone where magnetic fabric results are approximately consistent with the estimated consequences of the kinematic model. The tectonic stress field indicated by the magnetic fabrics is basically the same along the whole structural section and shows a NW to SE compression and shortening which is accordant with the regional compressive stress field of the Longmenshan fold-thrust belt.

关键词： magnetic fabric finite strain fault-related fold trishear zone Longmenshan.