• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.18 no.1
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• pp.73-81
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• 2020

Strontium (⁹⁰Sr) and nickel (⁵⁹Ni) have been considered as key radionuclides in the safety assessment of radioactive waste disposal. Through various efforts to impede the migration of radioactive nuclides underground, it has been established that some minerals generated from the corrosion of the waste containers have a positive chemical interaction with these radionuclides. Among these minerals we selected mackinawite (FeS), an iron and sulfur compound, and performed a sorption experiment for the Sr and Ni in FeS under anoxic and alkaline conditions by reflecting deep underground environments. The effects of pH on sorption were likewise investigated in the pH range of 8 ~ 12. As a result, it was found that strontium failed to exhibit a good sorption capacity in a weak alkaline range, while nickel showed a noticeably higher sorption affinity over the entire experimental pH range. Moreover, we determined that as the pH increased in the solution, the distribution coefficients (K_d) were increased for both nuclides, which reflects when an alkalinity increses, the surface of the mineral charges much negatively by detaching the hydrogen or cations on the mineral surface. Thus, it can be concluded that the cationic nuclides of Sr and Ni can attach easily to the mineral under strong alkalinity.

• Journal of Life Science
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• v.25 no.6
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• pp.631-637
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• 2015

Streptavidin, a protein produced by Streptomyces avidinii, strongly binds up to four molecules of vitamin H, d-biotin exhibiting the dissociation constant of about 10⁻¹⁵ M. This strong binding affinity has been applied for detection and characterization of numerous biological molecules suggesting expression and purification of functional streptavidin should be very useful for the application of this streptavidin-biotin interaction. To express a soluble streptavidin in Escherichia coli, We synthesized streptavidin genes and cloned into pET-22b plasmid, which uses T7 RNA polymerase/T7 promoter expression systems containing pelB leader for secretion into periplasmic space and six polyhistidine tags at C-terminus for purification of expressed proteins. Although streptavidin is toxic to Escherichia coli due to strong biotin binding property, streptavidin was expressed very sufficiently in a range of 10-20 mg/ml. In SDS-PAGE, the size of purified protein was shown as 17 kDa in denatured condition (boiling) and 68 kDa in native condition (without boiling) suggesting tetramerization of monomeric subunit by non-covalent association. Further analysis by size-exclusion chromatography supported streptavidin’s tetrameric structure as well. In addition, soluble streptavidin detected biotinylated proteins in westernblot indicating its functional activity to biotin. Taken these results together, it concluded that our simple expression system was able to show high yield, homotetrameric formation and biotin binding activity analogous to natural streptavidin.

• Reproductive and Developmental Biology
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• v.30 no.3
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• pp.169-174
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• 2006

To search of a new porcine pheromonal odorants, the comparative molecular similarity indices analysis(CoMSIA) between porcine odorant binding protein(pOBP) as receptor and ligands of green odorants 2-(Cyclohexyloxy)tetrahydrofurane derivatives as substrate molecule were conducted and disscused quantitatively. In the optimized CoMSIA model(I-AI) with chirality($I:\;C_{1'}(R),\;C_2(S)$) in substrate molecules and atom based fit alignment(AE) of the odorants the statistical PLS results showed the best predictability of the binding affinities based on the LOO cross-validated value ${r^2}_{cv.}\;(q^2=0.856)$ and non cross-validated conventional coefficient(${r^2}_{ncv.}=0.964)$). The structural distinctions of the highest active molecules were able to understand from the interaction between pOBP and green odorants in the contour maps with CoMSIA model.

• Bulletin of the Korean Chemical Society
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• v.14 no.6
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• pp.687-691
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• 1993

Complexation of $Cd^{2+},\;Pb^{2+}\;and\;Hg^{2+}$ ions with four cryptands were studied by potentiometry and solution calorimetry in various weight percent methanol-aqueous solvent at 25${\circ}$C under $CO_2$free nitrogen atmosphere. The stabilities of the complexes were dependent on the cavity size of macrocycles. The $Hg^{2+}$ ion stability constants are higher than those of $Cd^{2+}\;and\;Pb^{2+}$ ion. All the cryptands formed complexes having 1 : 1 (metal to ligand) mole-ratio except for $Hg^{2+}-L_1$ (cryptand 1,2b: 3,5-benzo-9,14,17-trioxa-1,7-diazabicyclo-(8,5,5) heptadecane) and $Cd^{2+}-L_2$ (cryptand 2,2b: 3,5-benzo-10,13,18,21-tetraoxa-1,7-diazabicyclo (8,5,5) eicosane) complexes. $Hg^{2+}-L_1$ complex was a sandwitch type, and the $Cd^{2+}-L_2$ complex showed two stepwise reactions. Thermodynamic parameters of the $Cd^{2+}-L_2$ complex were $6.08(log\;K_1)$, -7.28 Kcal/mol $({\Delta}H_1)$, and $4.78\;(log\;K_2)$, -4.62 Kcal/mol $({\Delta}H_2)$, respectively, for 1 : 1 and 2: 1 mole-ratio. The sequences of the selectivity were increased in the order of $Hg^{2+}\;>Pb^{2+}\;>Cd^{2+}$ ion for $L_3\;and\;L_4$ macrocycles, and the $L_2$-macrocycle has a selectivity for $Cd^{2+}$ ion relative to $Zn^{2+},\;Ni^{2+},\;Pb^{2+}\;and\;Hg^{2+}$ ions. Thus, it is expected that the $L_2$ can be used as carrier for seperation of the post transition metals by macrocycles-mediated liquid membrane because $L_2$ is not soluble in water, and the difference of stability constants of the metal complexes with $L_2$ are large as compared with the other transition metal complexes. The $^1H\;and\;^{13}C-NMR studies indicated that the nitrogen atoms of cryptands have greater affinity to the post transition metal ions than the oxygen atoms, and that the planarities of the macrocycles were lost by complexation with the metal ions because of the perturbation of ring current of benzene molecule attached to macrocycles and counter-anions.

• Molecules and Cells
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• v.45 no.3
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• pp.134-147
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• 2022

The anti-oxidant enzyme heme oxygenase-1 (HO-1) is known to exert anti-inflammatory effects. From a library of pyrazolo[3,4-d]pyrimidines, we identified a novel compound KKC080096 that upregulated HO-1 at the mRNA and protein levels in microglial BV-2 cells. KKC080096 exhibited anti-inflammatory effects via suppressing nitric oxide, interleukin1β (IL-1β), and iNOS production in lipopolysaccharide (LPS)-challenged cells. It inhibited the phosphorylation of IKK and MAP kinases (p38, JNK, ERK), which trigger inflammatory signaling, and whose activities are inhibited by HO-1. Further, KKC080096 upregulated anti-inflammatory marker (Arg1, YM1, CD206, IL-10, transforming growth factor-β [TGF-β]) expression. In 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridinetreated mice, KKC080096 lowered microglial activation, protected the nigral dopaminergic neurons, and nigral damage-associated motor deficits. Next, we elucidated the mechanisms by which KKC080096 upregulated HO-1. KKC080096 induced the phosphorylation of AMPK and its known upstream kinases LKB1 and CaMKKbeta, and pharmacological inhibition of AMPK activity reduced the effects of KKC080096 on HO-1 expression and LPS-induced NO generation, suggesting that KKC080096-induced HO-1 upregulation involves LKB1/AMPK and CaMKKbeta/AMPK pathway activation. Further, KKC080096 caused an increase in cellular Nrf2 level, bound to Keap1 (Nrf2 inhibitor protein) with high affinity, and blocked Keap1-Nrf2 interaction. This Nrf2 activation resulted in concurrent induction of HO-1 and other Nrf2-targeted antioxidant enzymes in BV-2 and in dopaminergic CATH.a cells. These results indicate that KKC080096 is a potential therapeutic for oxidative stress-and inflammation-related neurodegenerative disorders such as Parkinson's disease.

• Journal of Ginseng Research
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• v.48 no.2
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• pp.202-210
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• 2024

Background: Panax ginseng Meyer polysaccharides exhibit various biological functions, like antagonizing galectin-3-mediated cell adhesion and migration. Galectin-8 (Gal-8), with its linker-joined N- and C-terminal carbohydrate recognition domains (CRDs), is also crucial to these biological processes, and thus plays a role in various pathological disorders. Yet the effect of ginseng-derived polysaccharides in modulating Gal-8 function has remained unclear. Methods: P. ginseng-derived pectin was chromatographically isolated and enzymatically digested to obtain a series of polysaccharides. Biolayer Interferometry (BLI) quantified their binding affinity to Gal-8, and their inhibitory effects on Gal-8 was assessed by hemagglutination, cell migration and T-cell apoptosis. Results: Our ginseng-derived pectin polysaccharides consist mostly of rhamnogalacturonan-I (RG-I) and homogalacturonan (HG). BLI shows that Gal-8 binding rests primarily in RG-I and its β-1,4-galactan side chains, with sub-micromolar K_D values. Both N- and C-terminal Gal-8 CRDs bind RG-I, with binding correlated with Gal-8-mediated function. Conclusion: P. ginseng RG-I pectin β-1,4-galactan side chains are crucial to binding Gal-8 and antagonizing its function. This study enhances our understanding of galectin-sugar interactions, information that may be used in the development of pharmaceutical agents targeting Gal-8.

• Clean Technology
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• v.20 no.2
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• pp.189-201
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• 2014

Partial oxidation, $CO_2$ reforming and the oxidative $CO_2$ reforming of $CH_4$ to produce synthesis gas over supported Ni hydrotalcite-type ($Ni_{0.5}Ca_{2.5}Al$ catalyst) catalysts were carried out and the effects of metal supports (i.e.; Mg and Ca) on the formation of a stable double-layer structure on the catalysts were evaluated. The $CH_4$ reforming stability was determined to be affected by the differences in the interaction strength between the active Ni ions and support metal ions. Only a Ni-Mg-Al composition produced a highly stable hydrotalcite-type double-layered structure; while the Ni-Ca-Al-type composition did not. Such structure provides excellent stability for the catalyst (-80% efficiency) as confirmed by the long-term $CO_2$ reforming test (-100 h), while the Ni-Ca-Al catalyst exhibited deactivation phases starting at the beginning of the reaction. The interaction strength between the active metal (Ni) and the supporting components (Mg and Al) was determined by temperature-programed reduction (TPR) analyses. The affinity was also confirmed by the TPR temperature because the Ni-Mg-Al catalyst required a higher temperature to reduce the Ni relative to the Ni-Ca-Al catalyst. The highest initial activity for synthesis gas production was observed for the $Ni_{0.5}Ca_{2.5}Al$ catalyst; however, this activity decreased quickly due to coke formation. The $Ni_{0.5}Ca_{2.5}Al$ catalyst exhibited a high reactivity and was more stable than the other catalysts because it had a higher resistance to coke formation.

• Korean Journal of Microbiology
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• v.47 no.3
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• pp.200-208
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• 2011

Most problematic antibiotic resistance mechanism for MLS (macrolide-lincosamide-streptogramn B) antibiotics encountered in clinical practice is mono- or dimethylation of specific adenine residue at 2058 (E. coli coordinate) of 23S rRNA which is performed by Erm (erythromycin ribosome resistance) protein through which bacterial ribosomes reduce the affinity to the antibiotics and become resistant to them. ErmSF is one of the four gene products produced by Streptomyces fradiae to be resistant to its own antibiotic, tylosin. Unlike other Erm proteins, ErmSF harbors idiosyncratic long N-terminal end region (NTER) 25% of which is comprised of arginine well known to interact with RNA. Furthermore, NTER was found to be important because when it was truncated, most of the enzyme activity was lost. Based on these facts, capability of NTER peptide to inhibit the enzymatic activity of ErmSF was sought. For this, expression system for two different proteins to be expressed in one cell was developed. In this system, two plasmids, pET23b and pACYC184 have unique replication origins to be compatible with each other in a cell. And expression system harboring promoter, ribosome binding site and transcription termination signal is identical but disparate amount of protein could be expressed according to the copy number of each vector, 15 for pACYC and 40 for pET23b. Expression of NTER peptide in pET23b together with ErmSF in pACYC 184 in E. coli successfully gave more amounts of NTER than ErmSF but no inhibitory effects were observed suggesting that there should be dynamicity in interaction between ErmSF and rRNA rather than simple and fixed binding to each other in methylation of 23S rRNA by ErmSF.

• (The) Research of the performance art and culture
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• no.32
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• pp.131-169
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• 2016

We will study cultural sprauchling about Pungmul-Kut to find out the sphere of "Gui-myeong-gui" alongside Jeollanam-do, Jeollabuk-do western coast. In this area, there are some traits and terms about Gui-myeong-gui, a sort of Pungmul-Kut and Goon-go. Several Pungmul-Kuts which border the sphere of Gui-myeong-gui are Goon-gui in a southern direction, Unnyeongnongak of Honamudonongak in a eartern direction, and Yeongmujangnongak. The acculturation occurs in two ways. One is the possible acculturation with Goon-gi or Goon-go in coastal areas. The other is the acculturation with Honamudonongak. Especially, this phenomenan appears in double-way interaction. At first, there is the influence of Gui-myeong-gui in Honamudonongak. Kim Bau's style, which might relate to Gui-myeong-gui in Geommopojin, incorporate one of Panje of Honamudonongak through Park Namsik. This phenomenon is porved by the affinity between Eunjijaetji Galag of Honamudonongak GeollibKut and Eungmagaenggaeng Galag of Goon-go, and by the similarity to Neonari-Galag. In case of Neonari-Galag, the role of Jing in Neonari-Galag is replaced by Janggu in Honamudonongak, because of the geatest popularity of Janggu in those days. Secondly, there is the influence of Honamudonongak in Gui-myeong-gui. Northern sphere of Gui-myeong-gui like Buan-gun, Okgu-gun has been influenced since early $20^{th}$ century. In addition, the phenomenon which the sphere of Gui-myeong-gui accepts actively Honamudonongak could occur. So this thesis fragmentarilly checks the existence and traits of Gui-myeong-gui. Based on it, we would be able to reveal and reconstitute the nature of Gui-myeong-gui by understanding acculturation of Pungmul-Kut and by comparing Goon-go with Honamudonongak and Yeongmujangnongak in several regions. Also this thesis draws attention about meanings and effects of Yeonhuinongak's acceptace of Goon-beop.

• The Korean Journal of Archival Studies
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• no.42
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• pp.135-183
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• 2014

Korea has a high standard of IT environment to serve exhibit programs through the web with internet propagation and IT technology. However, the web exhibition of public institutions not only seem to introduce off-line exhibitions but also not to invigorate. It is caused by the lack of awareness, the cost of system installation and the lack of professional manpower. In this situation, OMEKA could suggest practical solutions to archives where need their own exhibition through the web. Especially, it would helpful for small record management organizations which are not enough budget and personal. OMEKA is an open source software program for digital collection and contents management. It has an affinity with users unlike traditional archives service programs. It also has been variously used by libraries, museums and schools because of exceptional exhibit functions. In this article, we introduce to the installation of a practical use about OMEKA. Regarding to OMEKA features, we consider it to raise exhibit effects. OMEKA would reduce the cost related to plans of exhibitions because it could display various contents and programs which reflecting characteristics of institutions. In addition, the availability of installation and widespread technological environment would lessen burden of public institutions. Using OMEKA, they would improve service level of public institutions and, make users satisfy. Therefore, they can change the social recognition of public institutions. OMEKA can contribute to various exercises of public records. It is not just the stereotypical system but, serves exhibition and collections with the strategy which each public institution would like to display. After all, it not only to connect to users with producers but also to improve the public image of institutions positively. Then, OMEKA would bring the great result through this interaction between public institutions and users.