• 대한화학회지
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• 제33권4호
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• pp.426-430
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• 1989

아미노 알콜에서 합성한 티아졸리딘치온 [4-(S)-IPTT, 4(S)-ETT]은 주석을 매개체로한 알돌 축합반응의 키랄 보조제로 이용되었다. Stannous triflate와 3-아세틸티아졸리딘-2-티온을 반응시켜 얻은 2가주석 엔올레이트를 어키랄 알데히드와 반응시켜 ${\beta}$-하이드록시 카르보닐 화합물을 입체선택적으로 얻었다. 이러한 키랄 보조제는 가메탄올 분해반응으로 쉽게 에스터화 되기 때문에 절대구조 동정을 용이하게 하는 장점도 있었다.

• 대한수학회보
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• 제53권5호
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• pp.1457-1469
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• 2016

In this paper, we study a class of Finsler metric. First, we find some rigidity results of the dually flat (${\alpha}$, ${\beta}$)-metric where the underline Riemannian metric ${\alpha}$ satisfies nonnegative curvature properties. We give a new geometric approach of the Monge-$Amp{\acute{e}}re$ type equation on $R^n$ by using those results. We also get the non-existence of the compact globally dually flat Riemannian manifold.

• 대한유전성대사질환학회지
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• 제14권2호
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• pp.182-185
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• 2014

GM1 gangliosidosis is a rare autosomal recessively inherited metabolic disease due to deficiency of ${\beta}$-galactosidase caused by mutations in the GLB1 gene. There have been three clinical subgroups in GM1 gangliosidosis, however it is difficult to differentiate because there is considerable overlap between classical phenotypes and clinical and imaging findings among the subgroups. Here, we report a Korean girl with type 2 GM1 gangliosidosis, who showed dysostosis multiplex and progressive neurological deterioration. Developmental regression was first noted at the age of 9 months, and she was diagnosed as GM1 gangliosidosis by ${\beta}$-galactosidase enzyme analysis and GLB1 mutation analysis at the age of 16 months.

• Journal of Applied Biological Chemistry
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• 제49권2호
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• pp.48-50
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• 2006

Four ursane-type triterpenoids, ursolic acid (1), 23-hydroxyursolic acid (2), corosolic acid (3), and tormentic acid (4), and a phytosterol, ${\beta}-sitosterol-3-O-{\beta}-D-glucoside$, were isolated from an EtOAcsoluble extract of the aerial parts of Potentilla discolor. The structures of 1-4 were identified by spectroscopic methods, particularly by extensive NMR studies. This is the first report on the isolation of compounds 1-4 from this plant.

• Archives of Pharmacal Research
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• 제20권2호
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• pp.115-121
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• 1997

Ile-269 in horse liver alcohol dehydrogenase isoenzyme S(HLADH-S) was mutated to serine by phosphorothioate-based site-directed mutagenesis in order to study the role of the residue in coenzyme binding. The specific activity of the mutant(1269S) enzyme to ethanol was increased 49-fold. All turnover numbers of 1269S enzyme toward 9 primary alcohols were increased. The mutant enzyme showed 3.6, 4.6, 11.6-fold higher catalytic efficiency for $5{\beta}$-androstane-3, 17-dione, $5{\beta}$-cholanic acid-3-one and retinal than wild-type, respectively. The reaction mechanism of 1269S enzyme was ordered bi bi as wild-type's. These results indicate that the hydrophobic interaction of Ile-269 residue with coenzyme plays an important role in dissociation of coenzyme from enzyme-coenzyme complex, which has been known as the rate limiting step of ADH reaction.

• 가정과삶의질연구
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• 제19권6호
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• pp.145-155
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• 2001

The purposes of this study were first to construct statistical and econometric models based on Amemiya\`s Type I Tobit mainly addressing the issue of statistical efficiency; second to explore income, price, and curvilinear age effects on the explained variable in order to illustrates its statistical marginal effects related to econometric issues; finally to provide invaluable insight for graphical simulations as a new interpretation approach using Tobit analysis. Results indicated that interpretation for the mean marginal effects of three possible cases of dependent variable was more likely to be evident to understand Tobit results compared to conventional analysis only using latent variable, beta. Results also revealed that prediction value of dependent variable can be possibly and easily projected by the independent variable changed whereas only beta value can not illustrate its projection as independent variables'changes.

• Bulletin of the Korean Chemical Society
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• 제25권6호
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• pp.881-888
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• 2004

By applying a catalytic amount of indium trichloride, regioselective ring-opening of epoxides to ${\beta}$-hydroxy ethers was established. While the alcoholysis of styrene oxides produed $S_N1$-type product, the alcoholysis of ${\alpha}$-heteroatom-substituted epoxides predominantly produced $S_N2$-type product.

• 약학회지
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• 제39권1호
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• pp.85-93
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• 1995

Acidic and alkaline hydrolysis of diol-type ginseng saponins produced a new glycoside, (20E)-ginsenoside Rh$_{3}$, and its stereoisomer (20Z)-, which were further subjected to alkaline by drolysis to give their aglycones, (20E)- and (20Z)-3$\beta$, 12$\beta$-dihydroxy-dammar-20(22),24-diene. The ratio of stereoisomeric mixtures was estimated to be ca. 5:1 from intensities of the peaks in $^{1}$H- and $^{13}$C-NMR spectra. The $^{1}$H- and $^{13}$C-NMR signals of ginsenoside Rh$_{3}$, which have remained unclarified, were completely assigned by the extensive application of modern NMR techniques.

• 한국정보통신학회:학술대회논문집
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• 한국정보통신학회 2017년도 추계학술대회
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• pp.425-428
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• 2017

본 논문에서는 진동 에너지를 이용하여 에너지를 수확하는 전파 정류 하베스팅 회로를 설계하였다. 설계된 회로는 저전압에서도 전력효율이 우수하도록 Beta-Multiplier를 이용하여 Body-Bias technique을 Negative Voltage Converter에 적용하였으며, Comparator를 Bulk-Driven type으로 설계하였다. 제안된 회로는 $0.35{\mu}m$ CMOS 공정으로 설계하였으며, 설계된 회로의 칩 면적은 $931{\mu}m{\times}785{\mu}m$이다.

• Nonlinear Functional Analysis and Applications
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• 제26권4호
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• pp.663-684
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• 2021

In this paper, we present some fixed point results for a general class of nonexpansive mappings in the framework of Banach space and also proposed a new iterative scheme for approximating the fixed point of this class of mappings in the frame work of uniformly convex Banach spaces. Furthermore, we establish some basic properties and convergence results for our new class of mappings in uniformly convex Banach spaces. Finally, we present an application to nonlinear integral equation and also, a numerical example to illustrate our main result and then display the efficiency of the proposed algorithm compared to different iterative algorithms in the literature with different choices of parameters and initial guesses. The results obtained in this paper improve, extend and unify some related results in the literature.