• 대한수학회지
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• 제53권2호
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• pp.331-346
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• 2016

The primary aim of this paper is to generalize a theorem of Hirzebruch for the complex 2-dimensional Bott manifolds, usually called Hirzebruch surfaces, to more general Bott towers of height n. To do so, we first show that all complex vector bundles of rank 2 over a Bott manifold are classified by their total Chern classes. As a consequence, in this paper we show that two Bott manifolds $B_n({\alpha}_1,{\ldots},{\alpha}_{n-1},{\alpha}_n)$ and $B_n({\alpha}_1,{\ldots},{\alpha}_{n-1},{\alpha}_n^{\prime})$ are isomorphic to each other, as Bott towers if and only if both ${\alpha}_n{\equiv}{\alpha}_n^{\prime}$ mod 2 and ${\alpha}_n^2=({\alpha}_n^{\prime})^2$ hold in the cohomology ring of $B_{n-1}({\alpha}_1,{\ldots},{\alpha}_{n-1})$ over integer coefficients. This result will complete a circle of ideas initiated in [11] by Ishida. We also give some partial affirmative remarks toward the assertion that under certain condition our main result still holds to be true for two Bott manifolds just diffeomorphic, but not necessarily isomorphic, to each other.

• 대한수학회보
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• 제55권6호
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• pp.1859-1868
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• 2018

In the present paper, we have proved the sharp inequality ${\mid}H_{3,1}(f){\mid}{\leq}4$ and ${\mid}H_{3,1}(f){\mid}{\leq}1$ for analytic functions f with $a_n:=f^{(n)}(0)/n!$, $n{\in}{\mathbb{N}},$, such that $$Re\frac{f(z)}{z}>{\alpha},\;z{\in}{\mathbb{D}}:=\{z{\in}{\mathbb{C}}:{\mid}z{\mid}<1\}$$ for ${\alpha}=0$ and ${\alpha}=1/2$, respectively, where $$H_{3,1}(f):=\left|{\array{{\alpha}_1&{\alpha}_2&{\alpha}_3\\{\alpha}_2&{\alpha}_3&{\alpha}_4\\{\alpha}_3&{\alpha}_4&{\alpha}_5}}\right|$$ is the third Hankel determinant.

• 한국식품영양과학회지
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• 제22권3호
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• pp.313-316
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• 1993

파 지하부로부터 분리된 2종의 diosgenin 배당체의 구조를 그의 분광학적 data와 화학적 실험 등의 방법으로 결정하였다. 그 결과, 이 두화합물의 구조는 diosgenin 3-O-$\alpha$-L-rhamnopyranosyl (1$\longrightarrow$2)-[$\alpha$-L-rhamnopyranosyl (1$\longrightarrow$4)]-$\beta$-D-glucopyranoside (1, dioscin)과 diosgenin 3-O-$\alpha$-L-rhamnopyranosyl (1$\longrightarrow$4)-$\alpha$-L-rhamnopyranosyl (1$\longrightarrow$4)]- [$\alpha$-L-rhamnopyranosyl (1$\longrightarrow$2]-$\beta$-D-glucopyranoside (2, saponin P-d)로서 기지 물질이나, saponin P-d를 부분가수분해하여 얻은 prosapogenin 중 compound 4는 문헌 미기재의 물질이다.

• 한국식품영양학회지
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• 제10권2호
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• pp.180-185
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• 1997

찹쌀 20%, 엿기름 4%를 가하여 7시간 동안 당화시켜 제조한 식혜는 말통스 10.1%, 한계덱스트린 7.3%, 말토트링스 1.3%, 글루코오스 0.18%, 밥알 1.75%를 나타냈다. 알코올 침전, Biogel P-2의 겔 크로마토그래피로 식혜의 한계덱스트린을 정제하여 1H-NMR 분석한 결과 한계덱스트린은 $\alpha$-1,4-글루코시드 결합과 $\alpha$-1,6-글루코시드 결합이 5:1로 이루어졌고, pullulanase 처리한 결과 말토오스와 말토헥사오스까지의 분포를 나타내어 멥쌀식혜에서 얻은 한계덱스트린가 구조가 같은 결과이다. 밥알의 당함량은 26.4%, 단백질 함량은 41.6%를 나타냈다. 참쌀식혜의 한계덱스트린과 밥알에 30unit/ml의 $\alpha$-아밀라아제, 글\ulcorner아밀라아제, $\alpha$-글루코시다아제, $\beta$-아밀라아제를 작용시킨 결과 글루코아밀라아제 외에는 일부밖에 가수분해하지 at하였다. 인체의 효소인 $\alpha$-아밀라아제와 $\alpha$-글루코시다아제를 함께 작용시킨 결과 한계덱스트린의 가수분해율은 18%, 밥알의 가수분해율은 26%를 나타냈다.

• Archives of Pharmacal Research
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• 제12권1호
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• pp.42-47
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• 1989

From the roots of Puisatiila koreana, three monodesmosides(pulsatilla saponins A, B and D) and two bisdesmosides(pulsatilla saponins F and H) were isolated. The structure of these saponins have been determined as hederagenin 3-O-${\beta}$-L-rhamnopyranosyl($1{\to}2$)- ${\alpha}$-L-arabinopyranoside(A), hederagenin 3-O-${\beta}$-D-glucopyrano syl($1{\to}4$) - ${\alpha}$-L-arabinopyranoside(B), hederagenin 3-O- ${\alpha}$-L-rhamnopyranosyl ($1{\to}2$)-[${\beta}$-D-glucopyranosyl($1{\to}4$]-${\alpha}$-L-arabinopyranoside(D), 3-O-${\alpha}$-L-rhamnopyranosyl($1{\to}2$)-{${\alpha}$-L-arabinopyranosyl hederagenin 28-O-${\alpha}$-L-rhamnopyrano syl($1{\to}4$)-${\beta}$-D-glucopyrano syl($1{\to}6$)-${\beta}$-D-glucopyranosyI ester (F) and 3-O-${\alpha}$-L-rhamnopyranosyl($1{\to}2$)-[${\beta}$-D-glucopyranosyl($1{\to}4$)]- ${\alpha}$-L-arabinopyranosyl hederagenin 28-O-${\alpha}$-L-lharnnopyranosyl($1{\to}4$)-${\beta}$-D-glucopyranosyl($1{\to}6$)-${\beta}$-D-glucop yranosyl ester(H) on the basis of chemical and spectral studies. Pulsatilla saponin B is the first report of its presence in plants but saponins A, D, F, and H have recently been isolated from the same genus p. cernua.

• 약학회지
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• 제35권4호
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• pp.314-318
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• 1991

A convenient method for the synthesis of indoprofen, which is a potent antiinflammatory agent, w described. Ethyl $\alpha$-(4-aminophenyl)propionate was prepared by nitration of ethyl $\alpha$-phenylpropionate, followed by reduction. Ethyl $\alpha$-[4-(1, 3-dioxo-2-iso-indolinyl)phenyl]propionate was obtained from condensation reaction of phthatic anhydride and ethyl $\alpha$-(4-aminophenyl)propionate. Indoprofen was prepared by reduction of ethyl $\alpha$-[3-(1, 3-dioxo-2-iso-indolinyl)phenyl]propionate with zinc dust-acetic acid, followed by hydrolysis of the resultant ethyl $\alpha$-[4-(1-oxo-2-iso-indolinyl)pheriyl]propionate.

• 대한수학회보
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• 제56권5호
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• pp.1117-1127
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• 2019

Let ${\mathcal{L}}_2=(-{\Delta})^2+V^2$ be the $Schr{\ddot{o}}dinger$ type operator, where nonnegative potential V belongs to the reverse $H{\ddot{o}}lder$ class $RH_s$, s > n/2. In this paper, we consider the operator $T_{{\alpha},{\beta}}=V^{2{\alpha}}{\mathcal{L}}^{-{\beta}}_2$ and its conjugate $T^*_{{\alpha},{\beta}}$, where $0<{\alpha}{\leq}{\beta}{\leq}1$. We establish the $(L^p,\;L^q)$-boundedness of operator $T_{{\alpha},{\beta}}$ and $T^*_{{\alpha},{\beta}}$, respectively, we also show that $T_{{\alpha},{\beta}}$ is bounded from Hardy type space $H^1_{L_2}({\mathbb{R}}^n)$ into $L^{p_2}({\mathbb{R}}^n)$ and $T^*_{{\alpha},{\beta}}$ is bounded from $L^{p_1}({\mathbb{R}}^n)$ into BMO type space $BMO_{{\mathcal{L}}1}({\mathbb{R}}^n)$, where $p_1={\frac{n}{4({\beta}-{\alpha})}}$, $p_2={\frac{n}{n-4({\beta}-{\alpha})}}$.

• 약학회지
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• 제45권2호
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• pp.147-152
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• 2001

The phytochemical study of the aerial parts of Artemisia sylvatica (Asteraceae) led to the isolation of nine sesquiterpene lactones, l$\alpha$-hydroperoxy-rupicolin A acetate (1), rupicolin B acetate (2), rupicolin A acetate (3), l$\alpha$-hydroxy-4$\alpha$-hydroperoxy-bishopsolicepolide (4), 1$\alpha$-hydroperoxy-4$\beta$-hydroxy-8$\alpha$-acetoxy-guaia-2,9,11 (13)-triene-6$\alpha$,12-oxide (5), 1$\alpha$-hydroperoxy-4$\alpha$-hydroxybishopsolicepolide (6), l$\alpha$,4$\beta$-dihydroxy-8$\alpha$-acetoxy-guaia-2,9,11(13)-triene-6$\alpha$,12-olive (7), rupicolin A (8) and l$\alpha$,4$\alpha$-dihydroxy-bishopsolicepolide (9). Their structures were established by chemical and spectroscopic methods.

• 대한수학회지
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• 제56권4호
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• pp.1049-1061
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• 2019

For ${\alpha}{\geq}1$, let $s_{\alpha}(n)={\lceil}{\alpha}n{\rceil}-{\lceil}{\alpha}(n-1){\rceil}$. A continued fraction $C({\alpha})=[0;s_{\alpha}(1),s_{\alpha}(2),{\ldots}]$ is considered and analyzed. Appealing to Diophantine approximation, we investigate the differentiability of $C({\alpha})$, and then show its singularity.

• Bulletin of the Korean Chemical Society
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• 제35권9호
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• pp.2781-2786
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• 2014

Human ${\alpha}_1$-antitrypsin (${\alpha}_1$-AT) is a natural inhibitor of neutrophil elastases and has several dozens of genetic variants. Most of the deficient genetic variants of human ${\alpha}_1$-AT are unstable and cause pulmonary emphysema. However, the most clinically significant variant, Z-type ${\alpha}_1$-AT, exhibits retarded protein folding that leads to accumulation of folding intermediates. These aggregate within the endoplasmic reticulum (ER) of hepatocytes, subsequently causing liver cirrhosis as well as emphysema. Here, we studied the role of an ER folding assistant protein Cpr5p on Z-type ${\alpha}_1$-AT folding. Cpr5p was induced > 2-fold in Z-type ${\alpha}_1$-AT-expressing yeast cells compared with the wild type. Knockout of CPR5 exacerbated cytotoxicity of Z-type ${\alpha}_1$-AT, and re-introduction of CPR5 rescued the knockout cells from aggravated cytotoxicity caused by the ${\alpha}_1$-AT variant. Furthermore, Cpr5p co-immunoprecipitated with Z-type ${\alpha}_1$-AT and facilitated its protein folding. Our results suggest that protein-folding diseases may be suppressed by folding assistant proteins at the site of causal protein biosynthesis.