• Korean Journal of Microbiology
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• v.43 no.4
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• pp.325-330
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• 2007

RNase E is an essential Escherichia coli endoribonuclease that plays a major role in the decay and processing of a large fraction of RNAs in the cell and expression of N-terminal domain consisted of 1-498 amino acids (N-Rne) is sufficient to support normal cellular growth. By utilizing these properties of RNase E, we developed a genetic system to screen for amino acid substitutions in the catalytic domain of the protein (N-Rne) that lead to various phenotypes. Using this system, we identified three kinds of mutants. A mutant N-Rne containing amino acid substitution in the S1 domain (I6T) of the protein was not able to support survival of E. coli cells, and another mutant N-Rne with amino acid substitution at the position 488 (R488C) in the small domain enabled N-Rne to have an elevated ribonucleolytic activity, while amino acid substitution in the DNase I domain (N305D) only enabled N-Rne to support survival of E. roli cells when the mutant N-Rne was over-expressed. Analysis of copy number of ColEl-type plasmid revealed that effects of amino acid substitution on the ability of N-Rne to support cellular growth stemmed from their differential effects on the ribonucleolytic activity of N-Rne in the cell. These results imply that the genetic system developed in this study can be used to isolate mutant RNase E with various phenotypes, which would help to unveil a functional role of each subdomain of the protein in the regulation of RNA stability in E. coli.

• Journal of Physiology & Pathology in Korean Medicine
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• v.22 no.4
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• pp.709-717
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• 2008

$Ch\acute{e}n\;Xiuyu\acute{a}n$(陳修園) was a famous doctor and educator of the late Tang Dynasty. He was well known both for his books for beginners, and for his unique medical theories based on his profound research of <$Sh\bar{a}ngh\acute{a}nl\grave{u}n$(傷寒論)> and <$J\bar{i}nku\grave{i}y\grave{a}ol\ddot{u}e$>. He wrote <$Y\bar{i}xues\bar{a}nz\grave{i}j\bar{i}ng$(醫學三字經)> to establish the basic textbook for the beginners to set up right principles in pursuing their medical career. <$Y\bar{i}xues\bar{a}nz\grave{i}j\bar{i}ng$> was written in rhyme form, so that it can be easily memorized and used in future practices. There are quite many medical books in rhyme form, but this book is very unique as $Ch\acute{e}n\;Xiuyu\acute{a}n$ annotated his own notes, which is rare in this form of books. This feature makes <$Y\bar{i}xues\bar{a}nz\grave{i}j\bar{i}ng$> very outstanding, also with the fact that $Ch\acute{e}n\;Xiuyu\acute{a}n$ was the one with profound understanding and original theories based on medical bibles such as <$N\grave{e}ij\bar{i}ng$(內經)> and <$Sh\bar{a}ngh\acute{a}nl\grave{u}n$(傷寒論)>. We have translated this precious educational material into korean, hoping that this work could be of any help to students of korean medicine. And while doing this work, we have found followings: <$Y\bar{i}xues\bar{a}nz\grave{i}j\bar{i}ng$> covers the entire fields of medicine from theoretical discussions to practical clinical information. Nevertheless, as this is written in rhyme form, there are few phrases that are not easily understood for the sake of rhyme. Beginners probably may have difficulties in reading this book. To make this difficulty alleviated, and to develop our own educational material, we need to study further on the notes that $Ch\acute{e}n\;Xiuyu\acute{a}n$ annotated himself.

• Journal of Nutrition and Health
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• v.33 no.2
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• pp.167-178
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• 2000

The effect of oral vitamin e (800IU/day) and C (500mg/day) supplementation for 10 days and/or smoking cessation for 5 days on oxidative damage to the red blood cells (RBC) of male smokers (22.2$\pm$0.2 years old) was studied. RBC were tested for their ability to protect against smoking-induced oxidative damage by measuring heme proteins (carboxyhemoglobin, hemoglobin, methemoglobin, oxyhemoglobin), hemolysis and thiobarbiturinc acid reactive substances (TBARS). Plasma levels of vitamin c, A, E, $\beta$-catotene, total cholesterol, glutamic pyruvic transaminase(GPT) and glutamic oxaloacetic transaminase(GOT) were also analyzed. In experiment one, a comparison was made of heme proteins and lipid damage to RBC, plasma antioxidant status (indexed by plasma levels of vitamin C, E, A and $\beta$-carotene) between smokers(n=56) and non-smokers (n=16). No differences were found in plasma antioxidant status, heme protein damage and TBARS concentration of RBC. In experiment two, 46 fasting male smokers from experiment one were divided into 4 groups. The groups were smoking with placebo group(SP, n=14), smoking cessation with vitamins supplementatin group (SV, n=13), smoking cessation with placebo group (NSP, n=9) and smoking cessation with vitamins supplementation group (NSV, n=10). After supplementing antioxidant vitamins, significant increases were seen in plasma vitamins supplementation group (NSV, n=10). After supplementing antioxidant vitamins, significant increases were seen plasma vitamin C (p<0.05) and vitamin E levels (p<0.05). The plasma vitamin E level was highest in the NSV group. Vitmain E and C supplementation provided some protection against heme proteins and lipid damage by lowering methemoglobin, hemolysis and TBARS concentration of RBC. Smoking cessation significantly decreased TBARS of RBC and plasma total cholesterol concentration. Supplementing vitamin E and C with smoking cessation considerably lowered plasma total cholesterol. These results point to a special association among smoking, oxidative damage and plasma antioxidant vitamin status. They indicate that increases in plasma antioxidant status can be detected after the supplementation of vitamin C and E and that smoking cessation had an additional effect on plasma vitamin E level. The present data suggest that improved antioxidant status induced by antioxidant supplementation or smoking cessation may help prevent oxidative damage in smokers.

• YAKHAK HOEJI
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• v.49 no.4
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• pp.299-305
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• 2005

Structure-activity relationship studies of allylamine type of antimycotics were carried out to evaluate the effect of naphthyl and methyl portion of naftifine. Compounds with 3,4-difluorophenyl (2a-5a), 4-hydroxyphenyl (2b-5b), 3-nitro­phenyl (2c-5c), 4-chlorobenzothiazoly (2d-5d) and 5-methylfurfural (2e-5e) instead of naphthyl group, and with hydrogen (3a-3e), methyl (4a-4e) and ethyl (5a-5e) in the place of methyl in naftifine were synthesized and tested for their in vitro anti-fungal activities against five different fungi. Fourteen compounds (3a, 4a, 5a, 3b, 4b, 5b, 3c, 4c, 5c, 3d, 4d, 3e, 4e and 5e) showed significant anti-fungal activities against T. mentagrophytes. (E)-N-(3-Phenyl-2-propenyl)-3,4-difluoro-ben­zenemethaneamine(3a), (E)_N_(3_phenyl_2_propenyl)_4_hydroxy_benzenemethaneamine(3b) and (E)-N-ethyl-N-(3-phenyl­2-propenyl)-3-nitro-benzenemethaneamine (5c) displayed moderate anti-fungal activities against all five different fungi.

• Journal of the Korean Mathematical Society
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• v.41 no.1
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• pp.51-64
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• 2004

Q-reflexive locally convex spaces are spaces where $\widehat{\bigotimes}_{n,s,\pi}\;{E_e}^{"}\;and\;\overline{{(P(^nE),\;\taub)_i}^'}$ are isomorphic in a canonical way for every n. We investigate properties and find examples of such spaces.

• Proceedings of the Korea Electromagnetic Engineering Society Conference
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• 2000.11a
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• pp.264-267
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• 2000

본 논문에서는 이동국의 안테나로부터 방사되는 전파의 일부가 인체에 흡수되므로써 기지국에서 수신되는 E$_{b}$ N$_{t}$의 감소에 대해 조사하였고, 감소된 E$_{b}$ N$_{t}$를 기준으로 하여 전파의 인체 흡수가 DS/CDMA BPSK 시스템의 성능에 미치는 영향을 분석하였다. 분석 결과, 인체에서의 흡수가 30[%]에서 40[%]로 증가할 때 기지국에서의 E$_{b}$ N$_{t}$, 값이 약 0.5 [dB] 정도 감소함을 알 수 있으며, 40 [%]에서 50[%]로 중가할 때에는 약 0.6 [dB] 정도 감소함을 알 수 있었다. 또한 시뮬레이션을 통해 사용자 수가 15 명일 때 약 2.5 [dB]의 E$_{b}$ N$_{t}$ 값에서 음성 서비스가 가능하다는 것을 알 수 있었다. 그리고 이러한 E$_{b}$ N$_{t}$ 값을 만족시키려면, 흡수율이 10 [%] 증가 할 때마다 안테나 방사 전력을 약 20 [mW] 이상 증가시켜야 한다는 것도 알아내었다. 것도 알아내었다.

• Journal of Photoscience
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• v.6 no.2
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• pp.67-70
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• 1999

trans-1-(9-Anthryl)-2-(n-pyridyl)ethene (t-n-APyE, n=2 or 4) and trans-1-(9-anthryl)-2-pyrazinylethene (T-APzE) exhibits solvent-dependent fluorescence and efficient trans)cis photoisomerization. Photochemical reactivities of t-2-APyE, t-4-APyE, and t-APzE have been investigated in nonpolar and polar solvents. In nonpolar solvent, parallel photocyclization reaction occurs very efficiently in competition with the fluorescence and photoisomerization. But, in polar solvent, photocyclization was not observed. It is probably due to the stabilization of charge separated state in polar solvent, which is an intermediate in photoisomerization reaction.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2002.05a
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• pp.559-562
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• 2002

본 논문에서는 최근 제한적으로 사용이 승인된 UWB(초광대역： Ultra-Wideband) 통신을 AWGN 하에서 다중 접속을 고려하지 않은 단일 사용사일 경우로 가정시, M진 값이 변화함에 따른 에러율과 성능 개선 기법으로 BCH를 채용시의 에러율을 비교 분석하였다. 기존에 연구되어 오던 변조로 PAM(Pulse Amplitude Modulation)과 PPM(Pulse Position Modulation)방식을 비교하였으며 에러율 $10^{-6}$을 기준으로 M=2, 4일 경우 PAM이 PPM보다 약 E$_{b}$/N$_{o}$ =3~4［dB］, M=8 이상의 경우 PPM이 약 E$_{b}$/N$_{o}$ =9［dB］, M=16일 경우 약 E$_{b}$/N$_{o}$ =15［dB］정도 성능이 우수하였다. AWGN 채널 하에서 에러 정정 부호인 BCH(15,7)를 도입하였을 경우 에러율 $10^{-6}$을 기준으로 PAM방식은 약 E$_{b}$/N$_{o}$ 가 약 1［dB］, PPM 방식은 M=2, 4일 경우 약 E$_{b}$/N$_{o}$ =1~1.5［dB］정도 개선되었다.

• Korean Journal of Microbiology
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• v.46 no.2
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• pp.148-151
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• 2010

The aim of this study was to investigate the erythromycin resistance patterns of Enterococci sp. present in cow milk. A total 110 erythromycin resistant Enterococci were isolated from milk samples; E. faecalis (n=101), E. avium (n=7), and E. durans (n=2). The minimum inhibitory concentration of erythromycin against 110 Enterococci were determined. The 66.3% of Entercocci (n=73) showed high level resistance (${\geq}64$ mg/ml). Among 110 isolates, 86.3% (n=95) showed $cMLS_B$ phenotype and 13.6% (n=15) showed $iMLS_B$ The aim of this study was to investigate the erythromycin resistance patterns of Enterococci sp. present in cow milk. A total 110 erythromycin resistant Enterococci were isolated from milk samples; E. faecalis (n=101), E. avium (n=7), and E. durans (n=2). The minimum inhibitory concentration of erythromycin against 110 Enterococci were determined. The 66.3% of Entercocci (n=73) showed high level resistance (${\geq}64$ mg/ml). Among 110 isolates, 86.3% (n=95) showed $cMLS_B$ phenotype and 13.6% (n=15) showed $iMLS_B$ phenotype. All of isolates have erm(B) determinant, 75.45% (n=83) have mef(A) an efflux system determinant. The majority of Enetrcococci isolated from raw milk samples in northern area of Gyeonggi-Do showed high level of resistance to erythromycin.

• Honam Mathematical Journal
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• v.30 no.3
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• pp.513-519
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• 2008

Let (R, m) be a Noetherian local ring with maximal ideal m, E := $E_R$(R/m) and let I be an ideal of R. Let M and N be finitely generated R-modules. It is shown that $H^n_I(M,(H^n_I(N)^{\vee})){\cong}(M{\otimes}_RN)^{\vee}$ where grade(I, N) = n = $cd_i$(I, N). We also show that for n = grade(I, R), one has $End_R(H^n_I(P,R)^{\vee}){\cong}Ext^n_R(H^n_I(P,R),P^*)^{\vee}$.