• Title/Summary/Keyword: chiA

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Analysis of the Involvement of Chitin-Binding Domain of ChiCW in Antifungal Activity, and Engineering a Novel Chimeric Chitinase with High Enzyme and Antifungal Activities

  • Huang, Chien-Jui;Guo, Shu-Huei;Chung, Shu-Chun;Lin, Yu-Ju;Chen, Chao-Ying
    • Journal of Microbiology and Biotechnology
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    • v.19 no.10
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    • pp.1169-1175
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    • 2009
  • An antifungal chitinase, ChiCW, produced by Bacillus cereus 28-9 is effective against conidial germination of Botrytis elliptica, the causal agent of lily leaf blight. ChiCW as a modular enzyme consists of a signal peptide, a catalytic domain, a fibronectin type-III-like domain, and a chitin-binding domain. When two C-terminal domains of ChiCW were truncated, $ChiCW{\Delta}FC$ (lacking the chitin-binding domain and fibronectin type III-like domain) lost its antifungal activity. Since $ChiCW{\Delta}C$ (lacking the chitin-binding domain) could not be expressed in Escherichia coli as $ChiCW{\Delta}FC$ did, a different strategy based on protein engineering technology was designed to investigate the involvement of the chitin-binding domain of ChiCW ($ChBD_{ChiCW}$) in antifungal activity in this study. Because ChiA1 of Bacillus circulans WL-12 is a modular enzyme with a higher hydrolytic activity than ChiCW but not inhibitory to conidial germination of Bo. elliptica and the similar domain composition of ChiA1 and ChiCW, the C-terminal truncated derivatives of ChiA1 were generated and used to construct chimeric chitinases with $ChBD_{ChiCW}$. When the chitin-binding domain of ChiA1 was replaced with $ChBD_{ChiCW}$, the chimeric chitinase named ChiAAAW exhibited both high enzyme activity and antifungal activity. The results indicate that $ChBD_{ChiCW}$ may play an important role in the antifungal activity of ChiCW.

ON A CONDITION OF OSCILLATORY OF 3-ORDER DIFFERENTIAL EQUATION

  • Cho, In-Goo
    • The Pure and Applied Mathematics
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    • v.2 no.1
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    • pp.35-41
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    • 1995
  • We consider the linear differential equations y〃'+ P($\chi$)y'+Q($\chi$)y=0 (1)(y"+P($\chi$)y)'-Q($\chi$)y =0 (2) Where (2) in the adjoint of (1) and P($\chi$), Q($\chi$) are continuous functions satisfying P($\chi$)$\geq$0, Q($\chi$)$\leq$0, P($\chi$)-Q($\chi$)$\geq$0 on [a, ${\alpha}$). (3) In this, we show that a condition a oscillatory of(1).(omitted)

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DISTRIBUTION OF THE VALUES OF THE DERIVATIVE OF THE DIRICHLET L-FUNCTIONS AT ITS a-POINTS

  • Jakhlouti, Mohamed Taib;Mazhouda, Kamel
    • Bulletin of the Korean Mathematical Society
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    • v.54 no.4
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    • pp.1141-1158
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    • 2017
  • In this paper, we study the value distribution of the derivative of a Dirichlet L-function $L^{\prime}(s,{\chi})$ at the a-points ${\rho}_{a,{\chi}}={\beta}_{a,{\chi}}+i{\gamma}_{a,{\chi}}$ of $L^{\prime}(s,{\chi})$. We give an asymptotic formula for the sum $${\sum_{{\rho}_{a,{\chi}};0<{\gamma}_{a,{\chi}}{\leq}T}\;L^{\prime}({\rho}_{a,{\chi}},{\chi})X^{{\rho}_{a,{\chi}}}\;as\;T{\rightarrow}{\infty}$$, where X is a fixed positive number and ${\chi}$ is a primitive character mod q. This work continues the investigations of Fujii [4-6], $Garunk{\check{s}}tis$ & Steuding [8] and the authors [12].

An Analyzing of the Current CHI Services in Korean Public Libraries (국내 공공도서관의 소비자건강정보 제공현황 조사분석 연구)

  • Noh, Young-Hee
    • Journal of the Korean Society for Library and Information Science
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    • v.45 no.2
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    • pp.415-437
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    • 2011
  • The increased interest in consumer health information(CHI) has brought about a rapid increase in CHI resources. There are diverse means for obtaining such information, and one CHI acquisition route is the public library. In the U.S. public libraries, the demand for CHI reference services is increasing, and a variety of projects to promote these services are in progress. On the other hand, Korean public library services for CHI is at a very basic level, and thus a very small amount of such research could be found. This study drew suggestions from a literature review of research studies in the U.S. and Canada, and analyzed public library CHI services in Korea. The findings are as follows. 1) Only 17.25% of public libraries in Korea provided CHI service, and it evidences very low needs and awareness for CHI services in Korea. 2) Only three kinds of services including CHI-related websites, users training, and promotional and marketing were provided, and only 13(1.74%) of libraries surveyed offered more than two kinds of services. 3) There were no CHI librarians, nor did any librarians receive CHI-related education. 4) ILL services, outreach services, and cooperation with CHI- and medical-related institutions for CHI services were not found. Therefore, this study suggests that more research on delivery strategies for CHI services should be conducted in the future.

DISCRETE SOBOLEV ORTHOGONAL POLYNOMIALS AND SECOND ORDER DIFFERENCE EQUATIONS

  • Jung, H.S.;Kwon, K.H.;Lee, D.W.
    • Journal of the Korean Mathematical Society
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    • v.36 no.2
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    • pp.381-402
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    • 1999
  • Let {Rn($\chi$)}{{{{ { } atop {n=0} }}}} be a discrete Sobolev orthogonal polynomials (DSOPS) relative to a symmetric bilinear form (p,q)={{{{ INT _{ } }}}} pqd$\mu$0 +{{{{ INT _{ } }}}} p qd$\mu$1, where d$\mu$0 and d$\mu$1 are signed Borel measures on . We find necessary and sufficient conditions for {Rn($\chi$)}{{{{ { } atop {n=0} }}}} to satisfy a second order difference equation 2($\chi$) y($\chi$)+ 1($\chi$) y($\chi$)= ny($\chi$) and classify all such {Rn($\chi$)}{{{{ { } atop {n=0} }}}}. Here, and are forward and backward difference operators defined by f($\chi$) = f($\chi$+1) - f($\chi$) and f($\chi$) = f($\chi$) - f($\chi$-1).

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Gamma Radiation Induced Mutagenesis of Lysobacter enzymogenes for Enhanced Chitinolytic Activity

  • Lee, Young-Keun;Kim, Kyoung Youl;Senthilkumar, M.
    • Journal of Radiation Industry
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    • v.4 no.1
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    • pp.65-71
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    • 2010
  • Two chitinase producing strains CHI2 and CHI4 were isolated from soybean rhizosphere soil. Both the strains belonged to Lysobacter enzymogenes as indicated by 16S rDNA sequence analysis. Though strain CHI2 and CHI4 produced extracellular chitinase, they differ in their chitinolytic activity. CHI4 produced approximately three times the higher amounts of enzyme than that of CHI2 under specified conditions. CHI2 produced $535.67U\;l^{-1}$ of chitinase after 48 h incubation with a specific activity of $3.91U\;mg^{-1}$ of protein while strain CHI4 produced $1584.13U\;l^{-1}$ of chitinase with a specific activity of $10.88U\;mg^{-1}$ protein. SDS-PAGE analysis indicated that the molecular weight of chitinase enzyme was approximately 45 kDa. A faint band with a molecular weight of 55 kDa reveals the possibility for the presence of another kind of chitin binding protein. Mutant library was developed by exposing the isolates to gamma rays at their $LD_{99}$ value (0.23 kGy). Totally, 11 mutants of CHI2 and CHI4 are reported to have enhanced chitinase activity. Several leaky mutant clones with decreased enzyme activity and a defective mutant (CHI2-M16) with complete loss of chitinase activity were also identified. CHI4-M18, CHI4-M8 and CHI4-M29 showed 78.8, 41.5, and 31.9% increased chitinase activity over wild type CHI4.

An Effective Algorithm for the Noncentral Chi-Squared Distribution Function (비중심카이제곱분포 함수에 대한 효율적인 알고리즘)

  • Gu, Son-Hee
    • The KIPS Transactions:PartA
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    • v.9A no.2
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    • pp.267-270
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    • 2002
  • The evaluation of the cumulative distribution function of the noncentral $\chi^2$ distribution is required in approximate determination of the power of the $\chi^2$ test. This article provides an algorithm for evaluating the noncentral $\chi^2$ distribution function in terms of a single "central" $\chi^2$ distribution function and compared various approximations.ximations.

A Study on the Design Characteries of Chi-pao Brand in China (중국 현대 치파오(Chi-pao) 브랜드의 디자인 특성 연구)

  • Ying, Liu;Soh, Hwang Oak
    • Journal of the Korean Society of Costume
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    • v.65 no.2
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    • pp.48-61
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    • 2015
  • Chi-pao is a kind of traditional clothes; it is regarded as a national costume, playing an irreplaceable role in the Chinese history. As China developed, the strict requirements on dresses did as well. History is a double-sided mirror,; we can know the past and we can find the direction ifor future development. when it comes to reform and openness, China imports foreign culture and exports domestic culture as well. This essay uses the history of Chi-pao as the background, consults the reference to analyse the brand of Chinese domestic Chi-pao characteristics, summarize the fashionable trend. Recently, Chi-pao is worn in many kinds of important occasions such as foreign affairs, public performances and so on. The purpose of this essay is to analyze the current situation of Chi-pao, make Chi-pao more international, and show the Chinese history to the world.

Common Fixed Point Theorems of Commuting Mappinggs

  • Park, Wee-Tae
    • The Mathematical Education
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    • v.26 no.1
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    • pp.41-45
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    • 1987
  • In this paper, we give several fixed point theorems in a complete metric space for two multi-valued mappings commuting with two single-valued mappings. In fact, our main theorems show the existence of solutions of functional equations f($\chi$)=g($\chi$)$\in$S$\chi$∩T$\chi$ and $\chi$=f($\chi$)=g($\chi$)$\in$S$\chi$∩T$\chi$ under certain conditions. We also answer an open question proposed by Rhoades-Singh-Kulsherestha. Throughout this paper, let (X, d) be a complete metric space. We shall follow the following notations : CL(X) = {A; A is a nonempty closed subset of X}, CB(X)={A; A is a nonempty closed and founded subset of X}, C(X)={A; A is a nonempty compact subset of X}, For each A, B$\in$CL(X) and $\varepsilon$>0, N($\varepsilon$, A) = {$\chi$$\in$X; d($\chi$, ${\alpha}$) < $\varepsilon$ for some ${\alpha}$$\in$A}, E$\sub$A, B/={$\varepsilon$ > 0; A⊂N($\varepsilon$ B) and B⊂N($\varepsilon$, A)}, and (equation omitted). Then H is called the generalized Hausdorff distance function fot CL(X) induced by a metric d and H defined CB(X) is said to be the Hausdorff metric induced by d. D($\chi$, A) will denote the ordinary distance between $\chi$$\in$X and a nonempty subset A of X. Let R$\^$+/ and II$\^$+/ denote the sets of nonnegative real numbers and positive integers, respectively, and G the family of functions ${\Phi}$ from (R$\^$+/)$\^$s/ into R$\^$+/ satisfying the following conditions: (1) ${\Phi}$ is nondecreasing and upper semicontinuous in each coordinate variable, and (2) for each t>0, $\psi$(t)=max{$\psi$(t, 0, 0, t, t), ${\Phi}$(t, t, t, 2t, 0), ${\Phi}$(0, t, 0, 0, t)} $\psi$: R$\^$+/ \longrightarrow R$\^$+/ is a nondecreasing upper semicontinuous function from the right. Before sating and proving our main theorems, we give the following lemmas:

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A Study on Developing the Guideline for CHI Reference Service (소비자건강정보(CHI) 참고서비스 가이드라인 개발에 관한 연구)

  • Noh, Younghee
    • Journal of Korean Library and Information Science Society
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    • v.44 no.2
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    • pp.345-376
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    • 2013
  • Because of increased concern regarding health and well-being, interest in consumer health information (CHI) has also increased, leading to a growing number of health-related websites. As a result, research has shown that public libraries are experiencing an increased demand for CHI-related reference services. The task of providing these services then falls on the public reference librarian, who is often untrained and inexperienced in this area. Therefore, improvements to how public libraries provide CHI reference services effectively are needed. This study analyzed the previous research at home and abroad, and developed CHI reference guidelines for public librarians. Guidelines developed in this study went through a verification process utilizing expert advice and a survey of public librarians.