• 제목/요약/키워드: Exponential Type

검색결과 425건 처리시간 0.022초

Effect of Copper on the Growth and Methanol Dehydrogenase Activity of Methylobacillus sp. Strain SK1 DSM 8269

  • Kim, Si W.;Kim, Young M.
    • Journal of Microbiology
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    • 제34권2호
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    • pp.172-178
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    • 1996
  • Methylobacillus sp. strain SK1, which grows only on methanol, was found to grow in the absence of added copper. The doubling time (t$_{d}$ = 1.3 h) of the bacterium growing at the exponential growth phase at 30.deg.C in the absence of copper was the same as that of the cell growing in the presence of copper. The bacterium growing after the exponential phase in the absence of copper, however, grew faster than the cell growing in the presence of copper. Cells harvested after thee arly stationary phase in the presence of copper were found to exhibit no methanol dehydrogenase (MDH) activity, but the amount and subunit structure of the enzyme in the cells were almost the same as that in cells harboring active MDH. Pellets of the cells harvested after the early stationary phase in the presence of copper were pale green. Cell-free extracts prepared from cells harvested at the early stationary phase in the presence of copper were pink and exhibited MDH activity, but it turned dark-green rapidly from the surface under air. The green-colored portions of the extracts showed no MDH activity and contained c-type cytochromes that were oxidized completely. The inactive MDH activity and contained c-type cytochromes that were oxidized completely. The inactive MDH proteins in the green portions were found to have antigenic sites identical to those of the active one as the inactive MDHs in cells grown in the presence of copper. The bacterium was found to accumulate copper actively during the exponential growth phase. MDH prepared from cells grown in the presence or absence of copper was found to be more stable under nitrogen gas than under air. Methanol at 10 mM was found to enhance the stability of the MDH under air.r.

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SHARP MOSER-TRUDINGER INEQUALITIES

  • Kim, Mee-Lae
    • 대한수학회지
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    • 제36권2호
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    • pp.257-266
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    • 1999
  • We used Carleson and Chang's method to give another proof of the Moser-Trudinger inequality which was known as a limiting case of the Sobolev imbedding theorem and at the same time we get sharper information for the bound.

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CERTAIN WEIGHTED MEAN INEQUALITY

  • Kim, Namkwon
    • Journal of the Korean Society for Industrial and Applied Mathematics
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    • 제18권3호
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    • pp.279-282
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    • 2014
  • In this paper, we report a new sharp inequality of interpolation type in $\mathbb{R}^n$. This inequality is for controlling weighted average of a function via $L^n$ norm of the gradient of a function together with its' certain exponential norm.

A Note On L$_1$ Strongly Consistent Wavelet Density Estimator for the Deconvolution Problems

  • Lee, Sungho
    • Communications for Statistical Applications and Methods
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    • 제8권3호
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    • pp.859-866
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    • 2001
  • The problem of wavelet density estimation is studied when the sample observations are contaminated with random noise. In this paper a linear wavelet estimator based on Meyer-type wavelets is shown to be L$_1$ strongly consistent for f(x) with bounded support when Fourier transform of random noise has polynomial descent or exponential descent.

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kε-Stability in Differential Systems

  • Choi, Sung Kyu;Gu, Yoon-Hoe;Ryu, Hyun Sook
    • 충청수학회지
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    • 제7권1호
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    • pp.183-192
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    • 1994
  • We investigate some properties $k_{\epsilon}$-stability which is an h-stability of exponential type.

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우리나라 중부 지방의 일최대강수량 추정에 관하여 (On the Estimation of Daily Maximum Precipitation in the Central Part of Korea.)

  • 이래영
    • 물과 미래
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    • 제11권1호
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    • pp.59-68
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    • 1978
  • According to the simplified Gringorten's method of extreme values from data samples, daily maximum precipitation and return period at several stations in the central part of Korea were estimated. And also, it was known that the distribution of daily maximum precipitation of Sogcho, Chuncheon, Kangreung, Seoul, Inchon, Suwon, Seosan, Cheongju and Daejeon area belong to an exponential type of distribution.

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Determination of Neurotoxin Gene Expression in Clostridium botulinum Type A by Quantitative RT-PCR

  • Shin, Na-Ri;Shin, Ji-Hun;Chun, Jeong Hoon;Yoon, So-Yeon;Kim, Bong Su;Oh, Hee-Bok;Rhie, Gi-eun
    • Molecules and Cells
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    • 제22권3호
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    • pp.336-342
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    • 2006
  • Real time reverse transcription (RT)-PCR was used to quantify the expression of the botulinum neurotoxin type A (BoNT/A) gene (cntA) by normalization with the expression of 16S rRNA. The method were confirmed by monitoring the mRNA levels of cntA during growth in five type A strains. In all but one of the strains the expression of cntA mRNA was maximal in the late exponential phase, and approximately 35-fold greater than in the early exponential phase. The concentration of the extracellular BoNT/A complex detected by ELISA was highest in stationary phase. Sodium nitrite and sorbic acid completely inhibited growth at 20 ppm and $4mg\;ml^{-1}$, respectively. CntA expression became lower in proportion to the concentration of sorbic acid, and this reduction was confirmed by mouse bioassay. Our results show that real time RT-PCR can be used to quantify levels of C. botulinum type A neurotoxin transcripts and to assess the effects of food additives on botulinal risk.