• The Bulletin of The Korean Astronomical Society
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• v.37 no.2
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• pp.85.2-85.2
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• 2012

The interstellar medium (ISM) of galaxies in the galaxy cluster can well be affected by the intracluster medium (ICM). Among many suggested environmental processes, ram pressure stripping can effectively remove gas through the interaction with the ICM. In fact, Cluster galaxies are lower in HI gas mass compared to their field counterparts, and in recent high resolution HI imaging studies, many galaxies in dense environments have been found to be ram pressure stripped in HI. However, it is still under debate whether the ICM pressure can also remove dense molecular gas from the galactic disk, which plays more important role in star formation and hence galaxy evolution. To answer this question, we have obtained high resolution 12/13 CO (2-1) data from the Sub Millimeter Array (SMA) of four galaxies at various HI stripping stages to study how the molecular gas properties change as the galaxy experiences the ICM pressure. We investigate the physical properties of molecular gas with 12/13 CO images. By comparing with other wavelength data, i.e. data(optical, HI, $H{\alpha}$, etc), we discuss how and in which timescale galaxies can migrate from the blue cloud to the red sequence due to ram pressure stripping.

• Korean Journal of Metals and Materials
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• v.47 no.8
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• pp.461-465
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• 2009

We study the diffusion of Ag based bimetallic nanoclusters supported on graphite. Using a molecular dynamics simulation, we reveal that the Ag clusters show rapid diffusion because of their hexagonal bottom layer. In order to decrease the rate of diffusion, we added Pt and Ni to distort the structure of the alloy cluster (i.e., the alloying method). We expected Pt to provide a stronger force on Ag atoms, and Ni to shorten the bond length and thereby change the structure of Ag cluster. However, the attempt was unsuccessful, because Pt and Ni atoms formed cores inside the Ag clusters. We therefore designed a collision system where large Ag clusters collide with small Pt or Ni clusters. Upon collision with Pt clusters, the diffusion showed little change, because Pt atoms are substituted at the Ag atomic site and form a perfectly ordered structure. The collision with Ni, however, deforms the bottom layer as well as the overall cluster structure and decreases diffusion. This outcome appoints toward the possibility of further application to the manufacture of durable nanocatalysts.

• The Plant Pathology Journal
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• v.17 no.6
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• pp.374.4-374
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• 2001

• The Bulletin of The Korean Astronomical Society
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• v.45 no.1
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• pp.29.4-29.4
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• 2020

Structure in the universe forms hierarchically with the small scales forming first and merging into larger scales. Galaxy clusters are at the pinnacle of the formation process. Peering far into the universe, we can observe galaxy clusters early in their evolution. SpARCSJ1049+56 is a galaxy cluster located at a redshift of 1.71. It has been shown to be rich in cluster galaxies, to have intense star formation, and to have a significant amount of molecular gas. Through careful control of systematics, we detected the weak-lensing signal from this distant galaxy cluster. I will present our HST infrared weak-lensing detection of the cluster with a focus on the method. Our lensing analysis found that the cluster is massive and is rare in a LambdaCDM universe. I will also present the Chandra X-ray discovery of cold gas coincident with the intense star formation and discuss the implications of the detection.

• Development and Reproduction
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• v.16 no.4
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• pp.315-320
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• 2012

The gDNA isolated from Cyclina sinensis from Gochang (GOCHANG), Incheon (INCHEON) and a Chinese site (CHINESE), were amplified by PCR. Here, the seven oligonucleotide decamer primers (BION-66, BION-68, BION-72, BION-73, BION-74, BION-76, and BION-80) were used to generate the unique shared loci to each population and shared loci by the three cyclina clam populations. As regards multiple comparisons of average bandsharing value results, cyclina clam population from Chinese (0.763) exhibited higher bandsharing values than did clam from Incheon (0.681). In this study, the dendrogram obtained by the seven decamer primers indicates three genetic clusters: cluster 1 (GOCHANG 01~GOCHANG 07), cluster 2 (INCHEON 08~INCHEON 14), cluster 3 (CHINESE 15~CHINESE 21). The shortest genetic distance that displayed significant molecular differences was between individuals 15 and 17 from the Chinese cyclina clam (0.049), while the longest genetic distance among the twenty-one cyclina clams that displayed significant molecular differences was between individuals GOCHANG no. 03 and INCHEON no. 12 (0.575). Individuals of Incheon cyclina clam population was somewhat closely related to that of Chinese cyclina clam population. In conclusion, our PCR analysis revealed a significant genetic distance among the three cyclina clam populations.

• Journal of Microbiology
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• v.33 no.2
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• pp.95-102
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• 1995

A probability identification matrix of acidophilic Streptomyces was constructed. The phenetic data of the strains were derived from numerical classification described by Seong et al. The minimum number of diagnostic characters was determined using computer programs for calculation of different separation indices. The resulting matrix consisted of 25 clusters versus 53 characters. Theoretical evaluation of this matrix was achieved by estimating the chuster overlap and the identification scores for the Hypothetical Median Organisms (HMO) and for the representatives of each cluster. Cluster overlap was found to be relatively small. Identification scores for the HMO and the randomly selected representatives of each cluster were satisfactory. The matrix was assessed practically by applying the matrix to the identification of unknown isolates. Of the unknown isolates, 71.9% were clearly identified to one of eight clusters. The numerical classification data was also used to design a selective isolation medium for antibiotic-producing organisms. Four chemical substances including 2 antibiotics were determined by the DLACHAR program as diagnostic for the isolation of target organisms which have antimicrobial activity against Micrococcus luteus. It was possible to detect the increased rate of selective isolation on the synthesized medium. Theresults show that the numerical phenetic data can be applied to a variety of purposes, such as construction of identification matrix and selective isolation medium for acidophilic antinomycetes.

• The Bulletin of The Korean Astronomical Society
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• v.44 no.2
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• pp.39.3-39.3
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• 2019

Ram pressure stripping due to the intracluster medium (ICM) is an important environmental process, which causes star formation quenching by effectively removing cold interstellar gas from galaxies in dense environments. The evidence of diffuse atomic gas stripping has been reported in several HI imaging studies. However, it is still under debate whether molecular gas (i.e., a more direct ingredient for star formation) can be also affected and/or stripped by ram pressure. The goal of this thesis is to understand the impact of ram pressure on the molecular gas content of cluster galaxies and hence star formation activity. To achieve this, we conducted a series of detailed studies on the molecular gas properties of three Virgo spiral galaxies with clear signs of active HI gas stripping (NGC 4330, NGC 4402, and NGC 4522) based on high-resolution CO data obtained from the Submillimeter Array (SMA) and Atacama Large Millimeter/submillimeter Array (ALMA). As a result, we find the evidence that the molecular gas disk also gets affected by ram pressure in similar ways as HI even well inside of the stellar disk. In addition, we detected extraplanar 13CO clumps in one of the sample, which is the first case ever reported in ram pressure stripped galaxies. By analyzing multi-wavelength data (e.g., Hα, UV, HI, and CO), we discuss detailed processes of how ram pressure affects star formation activities and hence evolution of cluster galaxies. We also discuss the origin of extraplanar 13CO, and how ram pressure can potentially contribute to the chemical evolution of the ICM.

• Development and Reproduction
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• v.14 no.3
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• pp.163-170
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• 2010

The gDNA isolated from Korean cuttle fish (Sepia esculenta Hoyle) from Sockcho (SOCKCHO), Seocheon (SEOCHEON), Incheon (INCHEON) and Vietnamese cuttle fish (VIETNAM), were amplified by PCR. Here, the seven selected primers (BION-A07, BION-A09, BION-A11, BION-A20, BION-B04, BION-B06, and BION-B14) were used to generate the unique shared loci to each population and shared loci by the four cuttle fish populations. In this study, the primer BION-A11 detected 112 shared loci by the four populations, major and/or minor fragments of sizes 300 bp, 400 bp, 700 bp and 1,000 bp, respectively, which were identical in all samples. The dendrogram obtained by the seven primers indicates five genetic clusters: cluster 1 (SOCKCHO 01-SOCKCHO 07), cluster 2 (SEOCHEON 08-SEOCHEON 10), cluster 3 (SEOCHEON 11-SEOCHEON 14), cluster 4 (INCHEON 15-INCHEON 21), and cluster 5 (VIETNAM 22-VIETNAM 28). The shortest genetic distance that displayed significant molecular differences was between individuals 25 and 26 from the Vietnamese cuttle fish (0.025), while the longest genetic distance among the twenty-eight cuttle fishes that displayed significant molecular differences was between individuals SOCKCHO no. 02 and SEOCHEON no. 12 (0.640). Individual of Seocheon and Incheon cuttle populations was somewhat closely related to that of Vietnamese cuttle fish population. Even though it could not be affirmed by a single case, such a result seems to be closely connected that the Korean peninsula is subject to climate changes by global warming. In conclusion, our PCR analyses revealed a significant genetic distance among the four cuttle fish populations.

• Bulletin of the Korean Chemical Society
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• v.25 no.6
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• pp.937-940
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• 2004

• Proceedings of the Korean Society of Potoscience Conference
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• spring
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• pp.40-40
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• 2004