• Proceedings of the KSAR Conference
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• 2003.06a
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• pp.50-50
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• 2003

모유에 존재하는 유지방구의 막을 구성하는 주된 당단백질인 하나인 lactadherin(과거에는 BA46로 일컬어짐)은 rotavirus에 의한 감염증상을 예방하는 것으로 보고되고 있다. 본 연구에서는 retrovirus vector system을 이용하여 Chinese Hamster Ovary (CHO) 세포에 tetracycline에 의해 발현이 제어되는 promoter 하의 lactadherin 유전자를 전이시킨 후lactadherin이 tetracycline에 의해 발현이 유도되는지의 여부를 실험하였다. 먼저 기초 실험으로 E. coli LacZ유전자를 이용하여 tetracycline에 의한 유도 여부를 조사하였다. Tet-On과 RevTRE-LacZ retrovirus를 co-infection시킨 NIH3T3 세포는 doxycycline (tetracycline 유도체)의 투여량에 비례하여 E. coli LacZ 유전자의 발현 정도가 증가하는 양상을 나타내었는데, 최대의 발현에 대한 doxycycline 농도는 1 $\mu\textrm{g}$/$m\ell$ 이상으로 나타났다. 이 예비실험의 결과를 바탕으로 Tet-On과 RevTRE-Ltd retrovirus vector를 이용하여 사람의 lactadherin 유전자의 유도적 발현을 검정하였는데, CHO 세포에서 lactadherin 유전자의 유도적 발현을 RT-PCR 기법을 이용하여 확인하였다. 표적세포 내에서 외부에서 도입된 유전자가 지속적으로 발현될 경우 심각한 생리적 부작용을 야기시킨다는 사실을 감안할 때, 본 실험의 결과는 유전자 치료와 형질전환동물의 생산에 크게 도움이 될 것으로 예상된다.

• Journal of the Korean Institute of Telematics and Electronics B
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• v.32B no.11
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• pp.153-162
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• 1995

When vector quantization is used in low rate image coding (e.g., R<0.5), the primary problem is the tremendous computational complexity which is required to search the whole codebook to find the closest codevector to an input vector. Since the number of code vectors in a vector quantizer is given by an exponential function of the dimension. i.e., L=2$^{nR}$ where Rn. To alleviate this problem, a multiple shell structure of hypercube feature maps (MSSHFM) is proposed. A binary HFM of k-dimension is composed of nodes at hypercube vertices and a multiple shell architecture is constructed by surrounding the k-dimensional hfm with a (k+1)-dimensional HFM. Such a multiple shell construction of nodes inherently has a complete tree structure in it and an efficient partial search scheme can be applied with drastically reduced computational complexity, computer simulations of still image coding were conducted and the validity of the proposed method has been verified.

• Korean Journal of Microbiology
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• v.28 no.2
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• pp.114-119
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• 1990

A yeast chromosomal superkiller gene (SK13) was cloned and expressed in $ski3^{-}$ Saccharomyces cerevisiae strains. The gene was fused to the structural region of E. coli lacZ gene at its C-terminus in a yeast-E. coli shuttle vector, pSR605. The fused gene complemented $ski3^{-}$ strains with SK13 activity and the quantitative level of expression was measured as determined by assaying $\beta$-galactosidase activity. The SDS-polyacrylamide gel electrophoresis and the Western blot analysis of this fused protein showed the immuno-reacted bands with a protein of the estimated molecular size (ca.250Kd).

• Communications of the Korean Mathematical Society
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• v.9 no.4
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• pp.927-931
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• 1994

Let G be a cyclic group of order 2 and let $S^1$ denote the unit circle in $R^2$ with the standard metric. We consider smooth G-vector bundles over $S^1$ when G acts on $S^1$ by reflection. Then the fixed point set of G on $S^1$ is two points ${z_0, z_1}$. Let $E$\mid$_{z_0} and E$\mid$_{z_1}$ be the fiber G-representation spaces at $z_0$ and $z_1$ respectively. We associate an orthogonal G-representation $\rho_i : G \to O(n)$ to $E$\mid$_{z_i}, i = 0, 1$. Let det $p\rho_i(g), g \neq 1$, be denoted by det $E$\mid$_{z_i}$ since det $\rho_i(g)$ is independent of choice of $\rho_i$.

• Proceedings of the KIEE Conference
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• 1989.11a
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• pp.37-40
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• 1989

When we analyze the magnetostatic problem by the FEM, it is a traditional method to use the magnetic vector potential as an unknown variable.(abbreviated to A Method) Therefore, we should differentiate this magnetic vector potential to get the magnetic flux density. In this procedure of differentiation, the accuracy of the calculation is reduced. In order to overcome this problem, this paper uses the magnetic flux density as an unknown variable.(abbreviated to B Method) The validity of this new method (B Method) to use the magnetic flux density directly as an unknown variable, is ensured as the result of the application example researches.

• Journal of the Korean Mathematical Society
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• v.61 no.5
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• pp.923-951
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• 2024

We consider a vector bundle map F : E₁ → E₂ between Lie algebroids E₁ and E₂ over arbitrary bases M₁ and M₂. We associate to it different notions of curvature which we call A-curvature, Q-curvature, P-curvature, and S-curvature using the different characterizations of Lie algebroid structure, namely Lie algebroid, Q-manifold, Poisson and Schouten structures. We will see that these curvatures generalize the ordinary notion of curvature defined for a vector bundle, and we will prove that these curvatures are equivalent, in the sense that F is a morphism of Lie algebroids if and only if one (and hence all) of these curvatures is null. In particular we get as a corollary that F is a morphism of Lie algebroids if and only if the corresponding map is a morphism of Poisson manifolds (resp. Schouten supermanifolds).

• BMB Reports
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• v.40 no.4
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• pp.547-553
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• 2007

Many motifs along the 1.2 kb myostatin promoter (MSTNpro) in sheep have been found by the MatInspecter program in our recent study. To further verify the role of the motifs and better understand the transcriptional regulation mechanism of the myostatin gene in sheep, the reporter gene EGFP (enhanced green fluorescent protein) was selected and the wild-type (W) vector MSTNPro$^W$-EGFP or motif-mutational (M) vector MSTNPro$^M$-EGFP were constructed. The transcriptional regulation activities were analyzed by detecting the fluorescence strength of EGFP in C2C12 myoblasts transfected with the vectors. The results showed that E-box (E) 3, E4, E5 and E7, particularly E3, E5 and E7, had important effects on the activity of the 1.2 kb sheep myostatin promoter. In addition, we also detected several other important motifs such as MTBF (muscle-specific Mt binding factor), MEF2 (myocyte enhancer factor 2), GRE (glucocorticoid response elements) and PRE (progesterone response elements) along the sheep myostatin promoter by the mutational analysis.

• Microbiology and Biotechnology Letters
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• v.31 no.3
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• pp.230-234
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• 2003

The Bacillus subtilis YvaE protein, the small multidrug resistance (SMR) family (TC #2.A. 7.1), is shown to catalyze efflux of multiple cationic drugs including many disinfectants, when it was cloned and expressed in Escherichia coli. When the yvaD gene was coexpressed with yvaE gene, the yvaD protein, encoded within a single operon with the yvaE gene, is shown to counteract the action ofYvaE. By ethidium efflux analysis, the cells harvoring a vector with yvaE gene showed a rapid ethidium efflux, compared with the control cells. These results clearly suggest that YvaE mediates drug export from the cell cytoplasm.

• Bulletin of the Korean Mathematical Society
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• v.42 no.2
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• pp.279-294
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• 2005

We study a real hypersurface M satisfying $L_{\xi}S=0\;and\;R_{\xi}S=SR_{\xi}$ in a complex hyperbolic space $H_n\mathbb{C}$, where S is the Ricci tensor of type (1,1) on M, $L_{\xi}\;and\;R_{\xi}$ denotes the operator of the Lie derivative and the Jacobi operator with respect to the structure vector field e respectively.

• Bulletin of the Korean Mathematical Society
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• v.37 no.2
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• pp.209-215
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• 2000

Let X be a locally convex space. A series of clearcut characterizations for the boundedness of vector measure $\mu{\;}:{\;}\sum\rightarrow{\;}X$ is obtained, e.g., ${\mu}$ is bounded if and only if ${\mu}(A_j){\;}\rightarrow{\;}0$ weakly for every disjoint $\{A_j\}{\;}\subseteq{\;}\sum$ and if and only if $\{\frac{1}{j^j}{\mu}(A_j)\}^{\infty}_{j=1}$ is bounded for every disjoint $\{A_j\}{\;}\subseteq{\;}\sum$.