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I269S와 I224S 이중변이 알코올 탈수소효소의 특성 (The Characteristics of I269S and I224S Double Mutant Horse Liver Alcohol Dehydrogenase)

  • 류지원;이강만
    • 약학회지
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    • 제41권6호
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    • pp.756-764
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    • 1997
  • Ile-224 in I269S mutant horse liver alcohol dehydrogenase isoenzyme S (HLADH-S) was mutated to serine by site-directed mutagenesis in order to study the role of the residue in c oenzyme binding to the enzyme. The specific activity of the I269S and I224S mutant enzyme to ethanol was increased 6-fold and all Michaelis constants($K_a,\;K_b,\;K_p,\;and\;K_q$,/TEX>) were larger than those for the wild-type and I269S enzyme. The substitution decreased the afffinity to coenzymes and increased the specific activity of the enzyme. The mutant enzyme showed the highest catalytic efficiency for octanol among the primary alcohols. But it didn`t have activities on retinoids and 5${\beta}$-cholanic acid-3-one. From these results, it was confirmed that the hydrophobic interaction of Ile-224 residue with coenzyme was related to coenzyme affinity in ADH reaction. The substitution also affected the substrate affinities to the enzyme.

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질화규소의 기계적 특성에 미치는 미세구조 및 소결조제의 영향 (Effect of Microstructures and Sintering Additives on the Mechanical Properties of Si$_3$N$_4$)

  • 박혜련;이오상;박희동;이재도
    • 한국재료학회지
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    • 제2권5호
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    • pp.330-336
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    • 1992
  • 질화규소 소재로 S${i_3}{N_4}$-8%${Y_2}{O_3}$, S${i_3}{N_4}$-6% ${Y_2}{O_3}$-2% $A{l_2}{O_3}$, S${i_3}{N_4}$-4% ${Y_2}{O_3}$-3% $A{l_2}{O_3}$, 그리고 S${i_3}{N_4}$-1% MgO-1% Si$O_2$의 4가지 조성을 선정하여 주상모양의 ${\beta}$-S${i_3}{N_4}$결정상을 성장시켰으며, XRD, SEM, 입도분석과 기계적 특성을 조사하였다. S${i_3}{N_4}$-8% ${Y_2}{O_3}$에서는 파괴인성값을 9.8MPa$m^{1/2}$까지 얻었으며 200$0^{\circ}C$에서 열처리한 후에도 파괴강도(>900MPa)의 감소없이 파괴인성이 8.0MPa$m^{1/2}$이상인 S${i_3}{N_4}$-6% ${Y_2}{O_3}$-2% ${l_2}{O_3}$, 와 S${i_3}{N_4}$-4% ${Y_2}{O_3}$-3% $A{A_2}{O_3}$를 얻었다. 질화규소의 파괴인성이 ${\beta}$-S${i_3}{N_4}$-결정상 크기의 증가에 따라 직선적으로 증가하는 관계를 갖는 파괴인성에 대한 미세구조의 영향을 고찰하였다.

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NOTE ON GOOD IDEALS IN GORENSTEIN LOCAL RINGS

  • Kim, Mee-Kyoung
    • 대한수학회보
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    • 제39권3호
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    • pp.479-484
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    • 2002
  • Let I be an ideal in a Gorenstein local ring A with the maximal ideal m and d = dim A. Then we say that I is a good ideal in A, if I contains a reduction $Q=(a_1,a_2,...,a_d)$ generated by d elements in A and $G(I)=\bigoplus_{n\geq0}I^n/I^{n+1}$ of I is a Gorenstein ring with a(G(I)) = 1-d, where a(G(I)) denotes the a-invariant of G(I). Let S = A[Q/a$_1$] and P = mS. In this paper, we show that the following conditions are equivalent. (1) $I^2$ = QI and I = Q:I. (2) $I^2S$ = $a_1$IS and IS = $a_1$S:sIS. (3) $I^2$Sp = $a_1$ISp and ISp = $a_1$Sp :sp ISp. We denote by $X_A(Q)$ the set of good ideals I in $X_A(Q)$ such that I contains Q as a reduction. As a Corollary of this result, we show that $I\inX_A(Q)\Leftrightarrow\IS_P\inX_{SP}(Qp)$.

조화 단진동자 파동함수를 쓴 원자핵의 LS에너지 행열요소 합법칙 (Nuclear LS-Energy Matrix Elements with the Harmonic Oscillator Shell Model Wave Functions for the Configurations ($I_1$$I_{1+1}$$I_1$$I_{1+1}$) and Sum Rules)

  • Chung-hum Kim;Soon-Kwon Nam
    • Nuclear Engineering and Technology
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    • 제14권1호
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    • pp.22-40
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    • 1982
  • 조화 단진동자 파동함수를 써서 원자핵의 LS에너지 행열요소를 계산하였다. 범위는 1$_1$= $l_{s}$ , $l_2$=lp, $l_3$=ld, 2s, $l_4$=1f, 2p, $l_{5}$ =1g, 2d, 3s라 ( $l_{i}$ $l_{i+1}$$l_{i}$ $l_{i+1}$)의 배치에 대한 것이었다. 계산결과는 Talmi적분 $I_1$과 Slater 적분 $F^{k}$ 를 써서 표시하였다. 또 여러가지 합법칙을 유도하고 이를 써서 계산의 결과를 검산하였다.하였다.

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Study on iodine Labelling (II) Efficient of Labelling Rose Bengal, Hippuran, and Human Serum Albumin in Small Scale

  • Kim, Jaerok
    • Nuclear Engineering and Technology
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    • 제4권3호
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    • pp.186-193
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    • 1972
  • Rose $Bengal-^{131}$ /I, $Hippuran-^{131}$ /I, $H.S.A-^{131}$ /I 등을 효과적으로 합성하기 위해 표지 반응액의 pH, 염의함량, 반응액중의 완충용액의 부피 및 합성장치등에 따르는 표지 반응수율을 검토하였다. Rose $Bengal-^131{ }$I 및 $Hippuran-^{131}$ /I 의 반응수율은 PH 5.6에서, $H.S.A-^{131}$ /I 반응수율은 pH 8.5에서 각각 가장 좋았다. 반응액중에 함유된 염은 $Hippuran-^{131}$ /I의 생성반응을 크게 저해 시켰으며 H.S.A.의 표지수율은 어느 범위안에서 오히려 약간 향상시켰다. Rose $Bengal-^{131}$ /I 나 $Hippuran-^{131}$ /I 를 소규모 합성할 경우는 밀폐된 용기가 효과적이었다. 이상의 결과에 따라 더 높은 표지수율과 좋은 재현성을 얻을 수 있는 반응조건을 확립하였으며 이에 따라 환원제가 함유된 국산 $Na^{131}$ /I를 사용하더라도 Rose $Bengal-^{131}$ /I과 $Hippurn=^{131}$ /I의 표지수율을 높일 수 있었다.

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C(S) extensions of S-I-BCK-algebras

  • Zhaomu Chen;Yisheng Huang;Roh, Eun-Hwan
    • 대한수학회논문집
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    • 제10권3호
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    • pp.499-518
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    • 1995
  • In this paper we consider more systematically the centralizer C(S) of the set $S = {f_a $\mid$ f_a : X \to X ; x \longmapsto x * a, a \in X}$ with respect to the semigroup End(X) of all endomorphisms of an implicative BCK-algebra X with the condition (S). We obtain a series of interesting results. The main results are stated as follows : (1) C(S) with repect to a binary operation * defined in a certain way forms a bounded implicative BCK-algebra with the condition (S). (2) X can be imbedded in C(S) such that X is an ideal of C(S)/ (3) If X is not bounded, it can be imbedded in a bounded subalgebra T of C(S) such that X is a maximal ideal of T. (4) If $X (\neq {0})$ is semisimple, C(S) is BCK-isomorphic to $\prod_{i \in I}{A_i}$ in which ${A_i}_{i \in I}$ is simple ideal family of X.

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A NOTE ON S-SETS IN A FIXED GROUP

  • Song, Hyung-Soo
    • 대한수학회보
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    • 제27권2호
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    • pp.113-120
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    • 1990
  • In this paper we introduce S(X, $x_{0}$) which is a generalization of Ellis group G(X, $x_{0}$), and S-sets in S(X, $x_{0}$). In particular we cind the sufficient condition for the group A(I) of all automorphisms of I and K=Iu to be isomorphic, where I is a minimal right ideal and u is an idempotent of I.f I.

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[r, s, t; f]-COLORING OF GRAPHS

  • Yu, Yong;Liu, Guizhen
    • 대한수학회지
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    • 제48권1호
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    • pp.105-115
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    • 2011
  • Let f be a function which assigns a positive integer f(v) to each vertex v $\in$ V (G), let r, s and t be non-negative integers. An f-coloring of G is an edge-coloring of G such that each vertex v $\in$ V (G) has at most f(v) incident edges colored with the same color. The minimum number of colors needed to f-color G is called the f-chromatic index of G and denoted by ${\chi}'_f$(G). An [r, s, t; f]-coloring of a graph G is a mapping c from V(G) $\bigcup$ E(G) to the color set C = {0, 1, $\ldots$; k - 1} such that |c($v_i$) - c($v_j$ )| $\geq$ r for every two adjacent vertices $v_i$ and $v_j$, |c($e_i$ - c($e_j$)| $\geq$ s and ${\alpha}(v_i)$ $\leq$ f($v_i$) for all $v_i$ $\in$ V (G), ${\alpha}$ $\in$ C where ${\alpha}(v_i)$ denotes the number of ${\alpha}$-edges incident with the vertex $v_i$ and $e_i$, $e_j$ are edges which are incident with $v_i$ but colored with different colors, |c($e_i$)-c($v_j$)| $\geq$ t for all pairs of incident vertices and edges. The minimum k such that G has an [r, s, t; f]-coloring with k colors is defined as the [r, s, t; f]-chromatic number and denoted by ${\chi}_{r,s,t;f}$ (G). In this paper, we present some general bounds for [r, s, t; f]-coloring firstly. After that, we obtain some important properties under the restriction min{r, s, t} = 0 or min{r, s, t} = 1. Finally, we present some problems for further research.

POSITIVE SOLUTIONS FOR MULTIPOINT BOUNDARY VALUE PROBLEMS WITH ONE-DIMENSIONAL p-LAPLACIAN OPERATOR

  • Xu, Fuyi;Meng, Zhaowei;Zhao, Wenling
    • Journal of applied mathematics & informatics
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    • 제26권3_4호
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    • pp.457-469
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    • 2008
  • In this paper, we study the existence of positive solutions for the following nonlinear m-point boundary value problem with p-Laplacian: $\{{{{(\phi_p(u'))'\;+\;f(t,u(t))=0, \;0<t<1,} \atop u'(0)={\sum}{^{m-2}_{i=1}}\;a_iu'(\xi_i),} \atop u(1)={\sum}{^k_{i=1}}\;b_iu(\xi_i)\;-\;{\sum}{^s_{i=k+1}}\;b_iu(\xi_i)\;-\;{\sum}{^{m-2}_{i=s+1}}\;b_iu'(xi_i),}$ where ${\phi}_p(s)$ is p-Laplacian operator, i.e., ${\phi}_p(s)=\mid s\mid^{p-2}s$, p>1, ${\phi}_q\;=\;({\phi}_p)^{-1}$, $\frac{1}{p}+\frac{1}{q}=1$, $1\;{\leq}\;k\;{\leq}\;s\;{\leq}m\;-\;2$, $b_i\;{\in}\;(0,+{\infty})$ with $0\;<\;{\sum}{^k_{k=1}}\;b_i\;-\;{\sum}{^s_{i=k+1}}\;b_i\;<\;1$, $0\;<\;{\sum}{^{m-2}_{i=1}}\la_i\;<\;1$, $0\;<\;{\xi}_1\;<\;{\xi}_2\;<\;{\cdots}\;<\;{\xi}_{m-2}\;<\;1$, $f\;{\in}\;C([0,\;1]\;{\times}\;[0,\;+{\infty}),\;[0,\;+{\infty}))$. We show that there exists one or two positive solutions by using fixed-point theorem for operator on a cone. The conclusions in this paper essentially extend and improve the known results.

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I-SSR 분석에 의한 노각나무 천연집단의 유전변이 (Genetic Variation in the Natural Populations of Korean Stewartia (Stewartia koreana Nakai) Based on I-SSR Analysis)

  • 양병훈;구영본;박용구;한상돈
    • 한국자원식물학회지
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    • 제19권1호
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    • pp.189-195
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    • 2006
  • 본 연구는 우리나라 특산수종이며 조경 및 원예적 가치가 높은 노각나무 유전변이를 조사하기 위해 6개 천연집단을 선발하여 DNA I-SSR 표지자를 사용, 유전다양성 및 유전구조를 조사하였다. 5개의 I-SSR primer(#813, 815, 818, 820, 823)에서 총 61개의 증폭산물을 관찰할 수 있었으며, 유전 다양성을 나타내는 P(Percentage of polymorphic loci)값과S.I.(Shannon's information Index)가 남쪽에 분포하는 오봉산(P=88.5%, S.I.=0.467), 금산(P=86.9%, S.I.=0.427), 바랑산(P=83.6%, S.I.=0.425)집단이 높았으며, 북쪽(내륙)에 분포하는 소백산(P=80.3%, S.I.=0.396), 지리산(P=77.1%, S.I.=0.368), 가야산(P=75.4%, S.I.=0.358)집단은 낮았다. 전체 유전변이 중 11.8%만이 집단간에 기인하는 것으로 나타났고, 나머지 88.2%는 집단내 개체간의 차이에서 기인하였다. 유전거리를 이용하여 UPGMA법에 의한 유집분석을 실시한 결과 지리적 분포에 대한 뚜렷한 경향은 나타나지 않았다.