• Bulletin of the Korean Chemical Society
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• v.20 no.3
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• pp.337-340
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• 1999

Luminescence of bismuth activated CaS, CaS:Bi, prepared in sodium polysulfide is studied. Excitation spectrum of CaS:Bi shows a band at 350 nm due to the recombination process between holes in Na+Ca2+ and electrons in conduction bands, in addition to bands at 260 nm from band gap of CaS, and at 320 nm (1S0→1P1) and at 420 nm (1S0→3P1) from electronic energy transitions of Bi. Emission band at 450 nm is from 3P1→1S0 transition of Bi3+, bands at 500 nm and 580 nm correspond to recombinations of electron donors (Bi3+Ca2+ and VS2-) with acceptors (VCa2+ and Na+Ca2+). Emission band of 3P1→1S0 transition is shifted to longer wavelength from CaS:Bi to BaS:Bi, due to the increase of the Stokes shift by the decrease of the crystal field parameter from CaS:Bi to BaS:Bi.

• Applied Chemistry for Engineering
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• v.25 no.4
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• pp.392-395
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• 2014

(2S,3S,4S)-3,4-Dihydroxyglutamic acid (DHGA), a biologically active ${\alpha},{\beta}$-dihydroxy-${\gamma}$-amino acid, was efficiently synthesized from a readily available D-serine derivative in 30% overall yield over 11 steps. The key stereoselective $OsO_4$-catalyzed dihydroxylation reaction controlled by an N-diphenylmethylene group on the amino group of ${\gamma}$-amino-${\alpha},{\beta}$-unsaturated (Z)-ester successfully introduced the diol moiety of the intermediate 5a in 86% with more than 10 : 1 diastereomeric ration. Then it was in turn successfully converted to the desired target compound, (2S,3S,4S)-3,4-DHGA, via simple oxidation and hydrolysis in a highly stereoselective manner and a higher yield than the previous syntheses. This result strongly supports that our synthetic methodology of stereoselective $OsO_4$-catalyzed dihydroxylation should be useful in stereoselctive synthesis of various bioactive compounds with an amino diol moiety.

• Communications of the Korean Mathematical Society
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• v.9 no.3
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• pp.641-648
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• 1994

Let M be a minimally immersed closed hypersurface in $S^{n+1}$, II the second fundamental form and $S = \Vert II \Vert^2$. It is well known that if $0 \leq S \leq n$, then $S \equiv 0$ or $S \equiv n$ and totally geodesic hypersheres and Clifford tori are the only possible minimal hypersurfaces with $S \equiv 0$ or $S \equiv n$ ([6], [2]). From these results, Chern suggested some questions on the study of compact minimal hypersurfaces on the sphere with S =constant: what are the next possible values of S to n, and does in the ambient sphere\ulcorner By the way, S is defined extrinsically but, in fact, it is an intrinsic invariant for the minimal hypersurface, i.e., S = n(n-1) - R, where R is the scalar, curvature of M. Some partial answers have been obtained for dim M = 3: Assuming $M^3 \subset S^4$ is closed and minimal with S =constant, de Almeida and Brito [1] proved that if $R \geq 0$ (or equivalently $S \leq 6$), then S = 0, 3 or 6, Peng and Terng ([5]) proved that if M has 3 distint principal curvatures, then S = 6, and in [3] Chang showed that if there exists a point which has two distinct principal curvatures, then S = 3. Hence the problem for dim M = 3 is completely done. For higher dimensional cases, not much has been known and these problems seem to be very hard without imposing some more conditions on M.

• Journal of the Korean Chemical Society
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• v.32 no.6
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• pp.588-592
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• 1988

A chiral recognition was observed in aminolysis of 3-acyl-4(S)-isopropyl-1,3-thiazolidine-2-thione by racemic amine to give an optically active amide (S-excess) and amine (R-excess). This procedure can be applied to synthesis of macrocyclic diamide macrocyclic spermidine alkaloid, and peptide. The rate of this aminolysis is remarkably affected by steric surrounding; completion of reaction can be easily judged by the disappearance of the original yellow color of 4(S)-AITT. These features of the aminolysis suggested a potential recognition racemic amines by a chiral 4 (S)-AITT derivative. Thus 4 (S)-AITT was synthesized from 4 (S)-isopropyl-1, 3-thiazolidine-2-thione and carboxylic acids.

• Applied Chemistry for Engineering
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• v.3 no.2
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• pp.189-193
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• 1992

The success of 3M's worldwide Pollution Prevention Pays (3P) Program convinced 3M's top management that the program should be expanded into a comprehensive environmental management system called 3P Plus. The emphasize of the 3P Plus program is to continually minimize the environmental impact of 3M processes, products, and operations to include energy management, resource recovery, and other initiatives. 3M's experience with the 3P and 3P Plus programs will be described. 3M's experience can serve as a model for other multi-national companies interested in sustainable development and economic growth with environmental protection.

• Korean Journal of Environment and Ecology
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• v.26 no.5
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• pp.682-693
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• 2012

This study was intented to understand the insects diversity and forest in DMZ, and provide data and information required to preserve living creatures and geological management, and basic information for the management and preservation policies. This study has surveyed insects diversity by habitat types in Middle Inland of DMZ, Korea from 15 to 19 September, 2009. Totally there were 128 species belonging to 53 families of 10 orders, among them, 7 endermic species, 3 management of exotic species and 25 designated species were showed. The highest was 26 species of Hemiptera(20.31%) and then next turn are 22 species of Coleoptera(17.19%) and 20 species of Hymenoptera(15.63%) respectively. Dominant species are Ceracris nigricornislaeta (Bolivar)(0.152) in S1, Menida violacea Motschulsky(0.218) in S2, Stomorhina obsoleta (Wiedemann)(0.171) in S3, Ducetia japonica (Thunberg)(0.212) in S4, Oedaleus infernalis Saussure(0.178) in S5, Sepedon aenescens Wiedemann(0.268) in S6, Adelphocoris triannulatus (Stal)(0.257) in S7 and Ricania taeniata Stal(0.150) in S8 site. The diversity(H') and richness(RI) of insects at survey area as S2(H'=3.461, RI=9.64), S3(H'=3.457, RI=9.18) and S1(H'=3.447, RI=8.88) were higher than in the others and the lowest in S8(H'=2.790, RI=5.341). But the highest species evenness index(EI) occurred in S8(0.985).

• Bulletin of the Korean Chemical Society
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• v.2 no.4
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• pp.125-129
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• 1981

The addition reactions of cysteine without blocking amino and carboxyl groups to substituted and unsubstituted ${\beta}$-nitro-styrene derivatives were investigated. ${\beta}$-Nitrostyrene(1a), p-methyl-${\beta}$-nitrostyrene(1b), 3,4,5-trimethoxy-$[\beta}$ -nitrostyrene(1c), $[\varpi}$-3,4-methylenedioxy-${\beta}$ -nitrostyrene(1d), o-, m- and p-chloro-${\beta}$ -nitrostyrene (1e, 1f, 1g) and o-, m- and p-methoxy-${\beta}$-nitrostyrene (1h, 1i, 1j) easily undergo addition reactions with cysteine to form S-(2-nitro-1-phenylethyl)-L-cysteine(3a), S-[2-nitro-1-(p-methyl)phenyl-ethyl]-L-cysteine(3b), S-[2-nitro-1-(3',4',5'-trimethoxy) phenylethyl]-L-cysteine(3c), S-[2-nitro-1-($[\vatpi}$ -3',4'-methylenedioxy)phenylethyl]-L-cysteine(3d), S-[2-nitro-1-(o-chloro)phenylethyl]-L-cysteine(3e), S-[2-nitro-1-(m-chloro)-phenylethyl]-L-cysteine(3f), S-[2-nitro-1-(p-chloro)phenylethyl]-L-cysteine(3g), S-[2-nitro-1-(o-methoxy)phenylethyl]-L-cysteine(3h), S-[2-nitro-1-(m-methoxy)phenylethyl]-L-cysteine(3i) and S-[2-nitro-1-(p-methoxy)phenylethyl]-L-cysteine(3j), respectively. The structure of adducts were confirmed by means of UV-spectrum, IR-spectrum, molecular weight measurement and elemental analysis. The various factors effecting the yield of cysteine adducts to ${\beta}$-nitrostyrene derivatives were also studied.

• Journal of Microbiology and Biotechnology
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• v.15 no.3
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• pp.484-490
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• 2005

Human ribosomal protein S3 (rpS3), which has a DNA repair endonuclease activity, is a multifunctional protein. This protein is involved in DNA repair, translation, and apoptosis. In particular, rpS3 has a lyase activity, which cleaves the phosphodiester bond of damaged sites such as cyclobutane pyrimidine dimers and AP sites. Here, using deletion analysis, we identified that the repair endonuclease domain resides in the C-terminal region (165-243 aa) of rpS3. We also found that ectopic expression of GST-rpS3 in bacterial strain BL21 promoted the resistance of these cells to ultraviolet (UV) radiation and hydrogen peroxide ($H_{2}O_{2}$) treatment. The repair domain of rpS3 was sufficient to exhibit the resistance to UV irradiation and recover cell growth and viability, showing that the repair activity of rpS3 is responsible for the resistance to UV irradiation. Our study suggests that rpS3 is able to process DNA damage in bacteria via its repair domain, showing the resistance to genotoxic stress. This implies that rpS3-like activity could be operative in bacteria.

• BMB Reports
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• v.56 no.5
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• pp.302-307
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• 2023

Lyn, a tyrosine kinase that is activated by double-stranded DNA-damaging agents, is involved in various signaling pathways, such as proliferation, apoptosis, and DNA repair. Ribosomal protein S3 (RpS3) is involved in protein biosynthesis as a component of the ribosome complex and possesses endonuclease activity to repair damaged DNA. Herein, we demonstrated that rpS3 and Lyn interact with each other, and the phosphorylation of rpS3 by Lyn, causing ribosome heterogeneity, upregulates the translation of p-glycoprotein, which is a gene product of multidrug resistance gene 1. In addition, we found that two different regions of the rpS3 protein are associated with the SH1 and SH3 domains of Lyn. An in vitro immunocomplex kinase assay indicated that the rpS3 protein acts as a substrate for Lyn, which phosphorylates the Y167 residue of rpS3. Furthermore, by adding various kinase inhibitors, we confirmed that the phosphorylation status of rpS3 was regulated by both Lyn and doxorubicin, and the phosphorylation of rpS3 by Lyn increased drug resistance in cells by upregulating p-glycoprotein translation.

• Herbal Formula Science
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• v.5 no.1
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• pp.127-145
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• 1997

This study was aimed to investigate the anti-tumor and immune response effect of Samyongtang(S1; this medicine represents for 'ENERGIZER'), Yangjeongjejeoktang(S2; this is the 'INTERMEDIATE METHOD' of S1 and S3) and Onbeakwon(S3; this is 'ATTACK' the disease of mass) on the experimental rats induced by Sarcoma-180 and Methotrexate. And to observed the differences S1, S2, and S3 treatment groups. Tumor weight(TW) in vivo, interleukin-2(IL-2), hemagglutinin titer(H.A), hemolysin titer(HL), rossete forming cell(RFC), delayed type hypersensitivity(DTH), and natural killer cell activity(NKCA) in vivo were measured in rats. The obtained results were summarized as follows. 1. Tumor weight was decreased in all treatment groups (S2>S3>S1) as compared with control group, but the difference was not statistically significant each treatment groups. 2. Interleukin-2 was increased in all treatment groups (S1>S2>Ss) as compared with control group, but the difference was not statistically significant each treatment groups. 3. Hemagglutinin titer was increased in all treatment groups (S1>S2>S3) as compared with control group, but the difference was not statistically significant each treatment groups. 4. Hemolysin titer was increased in all treatment groups (S1>S2>S3) as compared with control group, but the difference was not statistically significant each treatment groups. 5. Rossete forming cell(RFC) was increased in all treatment groups (S1>S2>S3) as compared with control group, but the difference was not statistically significant each treatment groups. 6. Delayed type hyperseneitivity(DTH) was increased in S1, S2 treatment groups (S1>S2) as compared with control group, but it was decreased in S3 treatment group. Therefore, S1 group was statistically significant compared with S3 groups. 7. Natural killer cell activity(NKCA) was increased in all treatment groups (S2>S3>S1) as compared with control group, but the difference was not statistically significant each treatment groups. Based on the above mentioned results, it is suggested that S1, S2 and S3 will have anti-tumor substances and enhance effect of immune response. But the differences were not statistically significant in each treatment groups, except for delayed type hypersensitivity.