• 제목/요약/키워드: E-transformation

검색결과 845건 처리시간 0.025초

Gene Disruption Using In Vivo and In Vitro Methylation in Streptomyces griseus

  • Maeng Jin-Soo;Bae Kyung-Sook;Kwak Jang-Yul
    • Journal of Microbiology and Biotechnology
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    • 제16권9호
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    • pp.1472-1476
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    • 2006
  • Previous study demonstrated that the restriction barrier of Streptomyces griseus is almost completely bypassed by the Streptomyces-E. coli shuttle vectors passed through the E. coli GM161 strain and methylated with AluI and HpaII methyltransferases. The same DNA methylation of the genomic DNA fragments cloned the nonreplicative vectors generated integrative transformation and gene disruption of their chromosomal counterparts at high efficiencies in S. griseus. This result indicated that the efficiency of gene disruption depends on the efficient transfer of the incoming DNA into bacterial hosts.

Pseudomonas fluorescens에 있는 하나의 Plasmid가 말론산 대사에 관련된 유전자를 가지고 있다는 증거 (Evience that a Plasmid Endoces Genes for Metabolism of Malonte in Pseudomonas fluorescens)

  • 김유삼;김은주
    • 미생물학회지
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    • 제32권3호
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    • pp.192-197
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    • 1994
  • 말론산을 탄소원으로 하여 성장하는 Pseudomonas fluorescens에서 60 kb 정도의 plasmid를 발견하였다. 이 plasmid를 curing한 Pseudomonas는 malonate 배지에서 자라지 못하였고 plasmid도 소실되었다. 또한 이 plasmid를 transformation과 conjugation으로 각각 E. coli와 cured P. fluorescens로 이동시킨 결과 이 plasmid를 받은 transformed E. coli와 conjugant P. fluorescens는 malonate를 탄소원으로 하여 성장하였고 malonate 대사에 관련된 효소인 malonate decarboxylase와 acetyl-CoA synthetase의 활성이 측정되었다. Western blotting을 통하여 tansformed E. coli에서 P. fluorescens와 동일한 acetyl-CoA synthetase가 malonate에 의해 induction됨을 확인하였다.

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e-learning 컨텐츠 품질에 관한 연구 (A Study on e-Learning Contents Quality)

  • 김영기;박성택;이승준
    • 디지털융복합연구
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    • 제6권2호
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    • pp.135-143
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    • 2008
  • The remarkable growth of the Internet since mid-l990s has expanded the e-learning market and brought the transformation of educational environments and methodology. It can be said that the e-learning has changed the educational paradigm. Korean government is firmly determined to support the diffusion of e-learning because of the benefits of e-learning. People seem to accept the e-learning when its contents have high quality. A lot of research have been conducted on e-learning, however, it was mostly about user's usage intention, satisfaction and educational effect. It can't seem that sufficient research efforts have been put into figuring out the role of e-learning contents quality in the expansion of e-learning. In this paper, we present the empirical study on the influence of e-learning contents quality on user's satisfaction and educational effect. We conducted an questionnaire survey on college students to collect data and found that the quality of e-learning contents has significant influence on the users' satisfaction.

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버네사이트 상변화 반응의 지화학적 반응 조절인자 연구 (A Review of Geochemical Factors Governing the Phase Transformation of Birnessite)

  • 남궁선이;전철민;이기현
    • 자원환경지질
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    • 제50권6호
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    • pp.545-554
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    • 2017
  • 버네사이트(birnessite)는 토양 및 심해저 환경에서 가장 흔히 발견되는 주요 망간수산화물 및 망간산화물(Mn(oxyhydr)oxides, 이하 망간산화물로 통칭) 중 하나로 일반적으로 나노 크기의 작은 입자로 구성되어 있으며 결정도가 매우 낮은 특징을 보인다. 특히 버네사이트는 구조 내 결함(structural defects)과 비어있는 양이온 자리(cation vacancies), 다양한 비율로 혼합된 구조 내 망간 산화수(mixed valences of structural Mn)의 특징에 따라 자연환경에서 다양한 생/지화학적 반응에 높은 반응성을 가지고 참여하는 것으로 알려져 있다. 이와 같이 다양한 생/지화학적 반응을 통해 버네사이트 주변에 존재하는 무기 및 유기물질의 자연 환경적 거동에 중요한 영향을 미칠 뿐 아니라 버네사이트의 상변화 반응이 수반되어 물리 화학적 특성이 전혀 다른 새로운 망간산화물이 형성된다. 본 리뷰 논문에서는 기존 선행 연구결과들을 바탕으로 버네사이트의 상변화 반응을 통해 형성되는 다양한 망간산화물들을 조사하고 반응에 영향을 미치는 다양한 지화학적 반응인자들을 검토하였다. 기존 선행연구 결과에 따르면 버네사이트의 상변화 반응은 용존 Mn(II) 및 용존 산소의 유무, 용액의 pH 조건, 그리고 함께 존재하는 양이온(i.e., $Mg^{2+}$)에 영향을 받는 것으로 사료되며, 다양한 반응인자들이 복합적으로 관여하는 버네사이트의 상변화 반응 경로에 대해서는 여전히 이해되지 않은 부분이 많은 것으로 확인되었다. 따라서, 앞으로 다양한 망간산화물들의 형성과 상변화 반응에 대한 보다 다양하고 심층적인 연구가 수행되어야 할 것이다.

Transformation of an Alkalin Protease Overproducer, Vibrio metschnikovii Strain RH530, and Improvement of Plasmid Stability by the par Locus

  • Chung, So-Sun;Shin, Yong-Uk;Kim, Hee-Jin;JIn, Chee-Hong;Lee, Hyune-Hwan
    • Journal of Microbiology and Biotechnology
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    • 제11권2호
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    • pp.222-228
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    • 2001
  • Vibrio metschnikovii strain RH530 is a non-pathogenic, industrially-important alkaline protease producer which has been isolated from wastewater. In this paper, we report on the transformation of this strain by using the method of electroporation. A field strength of $7.5\;kVcm^{-1}$ and $25\;{\mu}F$, and using a 0.2-cm cuvette, appeared to be the optimal conditions for electroporation of the cells with the recombinant pSBCm plasmid carrying the vapK alkaline protease gene and the ColE1 replicon. Cells were subjected to osmotic shock in order to remove extracelluar DNase, and adding 200 mM of sucrose to electroporation buffer cells showed an increased transformation efficiency. Maximum efficiency of transformation was obtained at an early exponential growth phase. Using all of the conditions mentioned above, we routinely obtained a transformation efficiency of more than $10^4{({\mu}g\;plasmid\;DNA)}^{-1}$. The stability of the plasmid pSBCm in V. metschnikovii RH530 was 25% after 18h of growth (27 generations) in the medium without antibiotic selection. The insertion of the par locus to the pSBCm increased the stability of the plasmid up to 42% without selective pressure. The increase in plasmid stability was accompanied by the increase in the productivity of alkaline protease in the recombinant V. metschnikovii strain RH530. Determining optimal conditions for the transformation of the industrially-important, nonpathogenic Vibrio strain, and the improvement of plasmid stability by introducing the par locus into the high copy number plasmid vector, will allow the development of procedures involved in the genetic manipulation of this strain, particularly for its use in the production of industrial enzymes such as alkaline protease.

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A Semantic Classification Model for e-Catalogs

  • Kim, Dong-Kyu;Lee, Sang-Goo;Chun, Jong-Hoon
    • 한국전자거래학회:학술대회논문집
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    • 한국전자거래학회 2004년도 e-Biz World Conference
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    • pp.302-309
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    • 2004
  • ·Catalogs -information about products and services -Contents + Classification Schema + Operational Issues ·What do we do with them? -[Schulten, et a;, 2001] ‥Narrow down search for complete set of applicable products ‥Comprehend individual description to the precision needed -Support other applications that use product information ‥SCM, ERP, e-Procurement, etc. ·Catalog Management System -Design, storage, navigation & retrieval, transformation, communication, publication(omitted)

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Photometric Transformation from RGB Bayer Filter System to Johnson-Cousins BVR Filter System

  • Park, Woojin;Pak, Soojong;Shim, Hyunjin;Le, Huynh Anh N.;Im, Myungshin;Chang, Seunghyuk;Yu, Joonkyu
    • 천문학회보
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    • 제40권2호
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    • pp.43.2-43.2
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    • 2015
  • The RGB Bayer filter system consists of a mosaic of R, G, and B filters on the grid of the photo sensors which typical commercial DSLR (Digital Single Lens Reflex) cameras and CCD cameras are equipped with. Lot of unique astronomical data obtained using an RGB Bayer filter system are available, including transient objects, e.g. supernovae, variable stars, and solar system bodies. The utilization of such data in scientific research requires that reliable photometric transformation methods are available between the systems. In this work, we develop a series of equations to convert the observed magnitudes in the RGB Bayer filter system (RB, GB, and BB) into the Johnson-Cousins BVR filter system (BJ, VJ, and RC). The new transformation equations derive the calculated magnitudes in the Johnson-Cousins filters (BJcal, VJcal, and RCcal) as functions of RGB magnitudes and colors. The mean differences between the transformed magnitudes and original magnitudes, i.e. the residuals, are (BJ - BJcal) = 0.064 mag, (VJ - VJcal) = 0.041 mag, and (RC - RCcal) = 0.039 mag. The calculated Johnson-Cousins magnitudes from the transformation equations show a good linear correlation with the observed Johnson-Cousins magnitudes.

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E-Governmentfor Efficient Governance: Instructive Cooperation of the Republic of Belarus and the Republic of Korea in the Sphere of e-Government

  • Tchouechov, Viktor I.;Zhmakina, Tatiana V.
    • 한국멀티미디어학회지
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    • 제22권1호
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    • pp.26-33
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    • 2018
  • The transformation of the processes of governance using the Information and Communication Technologies is aimed at bringing in faster and transparent service delivery, accountability, information sharing and people participation in the decision-making and government processes. The implementation of e-Government requires a comprehensive strategy that is not only sensitive to existing political and economic conditions and realities but is also benchmarked on global best practices. The article reviews the handbook E-Government and Governance Efficiency that provides an insight to research that is being undertaken in the e-Government area, gives an in-depth understanding of critical issues involved in e-Government, and provides expert opinion and recommendations for the Republic of Belarus to augment its potential. It studies the Korean experience on e-Government with special focus on such concepts as e-Government benchmarking, mGovernment, Smart Government and u-Government.

A High-Speed LSF Transformation Algorithm for CELP Vocoders

  • Min, So-Yeon;Bae, Myung-Jin
    • The Journal of the Acoustical Society of Korea
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    • 제20권1E호
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    • pp.20-24
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    • 2001
  • We propose the computation reduction method of real root method that is mainly used in the CELP(Code Excited Linear Prediction) vocoder. The real root method is that if polynomial equations have the real roots, we are able to find those and transform them into LSF[1]. However, this method takes much time to compute, because the root searching is processed sequentially in frequency region. But, the important characteristic of LSF is that most of coefficients are occurred in specific frequency region. So, the searching frequency region is ordered by each coefficient's distribution. And coefficients are searched in ordered frequency region. Transformation time can be reduced by this method than the sequential searching method in frequency region. When we compare this proposed method with the conventional real root method, the experimental result is that the searching time was reduced about 46% in average.

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