• The Bulletin of The Korean Astronomical Society
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• v.45 no.1
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• pp.30.1-30.1
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• 2020

The ASKAP-EMU survey is a deep wide-field radio continuum survey designed to cover the entire southern sky and a significant fraction of the northern sky up to +30°. Here, we report a discovery of a radio relic in the merging cluster SPT-CL J2023-5535 at z=0.23 from the ASKAP-EMU pilot 300 square degree survey (800-1088 MHz). The deep high-resolution data reveal a ~2 Mpc-scale radio halo elongated in the east-west direction, coincident with the intracluster gas. The radio relic is located at the western edge of this radio halo stretched ~0.5 Mpc in the north-south orientation. The integrated spectral index of the radio relic within the narrow bandwidth is α1088MHz800MHz = -0.76 ± 0.06. Our weak-lensing analysis shows that the system is massive (M200 = 1.04 ± 0.36 × 1015M⊙) and composed of at least three subclusters. We suggest a scenario, wherein the radio features arise from the collision between the eastern and middle subclusters. Furthermore, the direct link between the local AGN and the relic along with the discontinuities in X-ray observation hint us that we are looking at the site of re-acceleration.

• Proceedings of the Korean Fiber Society Conference
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• 2003.04a
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• pp.354-355
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• 2003

Since the discovery of sin91e-wall carbon nanotubes (SWNTs) there has been a flurry of research activity aimed at understanding their physical properties, elucidating their growth mechanisms and developing novel uses for them. Chemistry involving SWNTs is still in its infancy. This is due, in large part, to previous difficulties in obtaining reasonable quantities of highly purified SWNTs[1]. (중략)

• The Bulletin of The Korean Astronomical Society
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• v.40 no.1
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• pp.58.1-58.1
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• 2015

Gravitational-wave has been predicted by Einstein's general relativity in 1916, but its direct detection has failed to date despite of the persistent efforts in the last fifty years in the ground-based gravitational wave detectors. In the centennial year of the birth of general relativity, 'advanced LIGO', one of the most promising Earth-based gravitational wave detectors, plans to start commissioning for the successful discovery of gravitational waves. In addition, a pathfinder satellite of eLISA project, a space-based GW antenna by European Space Agency (ESA), will be launched in the mid of this year. In this talk, we review the current status of gravitational waves detection experiments and discuss its scientific impacts and the possibility of opening the new age of astronomy.

• Bulletin of the Korean Chemical Society
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• v.33 no.8
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• pp.2574-2580
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• 2012

The discovery that threosyl phosphonate nucleoside (PMDTA, $EC_{50}=2.53{\mu}M$) is a potent anti-HIV agent has led to the synthesis and biological evaluation of 5'-deoxy versions of threosyl phosphonate nucleosides. In the present study, (E)-3'-phosphonoalkenyl and 3'-phosphonoalkyl nucleoside analogues 13, 16, 20 and 23 were synthesized from acetol and tested for anti-HIV activity and cytotoxicity. The adenine analogue 16 was found to exhibit moderate in vitro anti-HIV-1 activity ($EC_{50}=22.2{\mu}M$).

• Korean Journal of Crystallography
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• v.18 no.1_2
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• pp.10-15
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• 2007

UDP-N-acetylglucosamine enolpyruvyl transferase (MurA; EC 2.5.1.7) catalyzes the first committed step of peptidoglycan biosynthesis in bacteria, i.e., transfer of enolpyruvate from phosphoenolpyruvate to UDP-N-acetyl-glucosamine. Because the crystallization condition contained a high concentration of ammonium sulfate, our inhibitor binding studies were not successful. Therefore, we employed a docking approach to investigate the inhibitor binding. Our results will be useful in structure-based design of specific inhibitors of MurA for antibacterial discovery.

• Journal of Computing Science and Engineering
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• v.3 no.2
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• pp.109-126
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• 2009

Taxonomies are widely used to classify information, and multiple (possibly competing) taxonomies often exist for the same domain. Given a set of correspondences between two taxonomies, it is often necessary to "merge" the taxonomies, thereby creating a unied taxonomy (e.g., that can then be used by data integration and discovery applications). We present an algorithm for merging taxonomies that have been related using articulations given as RCC-5 constraints. Two taxa Nand M can be related using (disjunctions of) the ve base relations in RCC-5: M; N ${\subseteq}$M; N ${\supseteq}$; N ${\oplus}$M (partial overlap of Nand M); and N ! M (disjointness: N ${\cap}$M = ${\varnothing}$). RCC-5 is increasingly being adopted by scientists to specify mappings between large biological taxonomies. We discuss the properties of the proposed merge algorithm and evaluate our approach using real-world taxonomies.

• Genomics & Informatics
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• v.10 no.1
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• pp.44-50
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• 2012

Pattern discovery in biological sequences (e.g., DNA sequences) is one of the most challenging tasks in computational biology and bioinformatics. So far, in most approaches, the number of occurrences is a major measure of determining whether a pattern is interesting or not. In computational biology, however, a pattern that is not frequent may still be considered very informative if its actual support frequency exceeds the prior expectation by a large margin. In this paper, we propose a new interesting measure that can provide meaningful biological information. We also propose an efficient index-based method for mining such interesting patterns. Experimental results show that our approach can find interesting patterns within an acceptable computation time.

• BMB Reports
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• v.47 no.6
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• pp.299-310
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• 2014

Cohesin is a multi-protein complex composed of four core subunits (SMC1A, SMC3, RAD21, and either STAG1 or STAG2) that is responsible for the cohesion of sister chromatids following DNA replication until its cleavage during mitosis thereby enabling faithful segregation of sister chromatids into two daughter cells. Recent cancer genomics analyses have discovered a high frequency of somatic mutations in the genes encoding the core cohesin subunits as well as cohesin regulatory factors (e.g. NIPBL, PDS5B, ESPL1) in a select subset of human tumors including glioblastoma, Ewing sarcoma, urothelial carcinoma, acute myeloid leukemia, and acute megakaryoblastic leukemia. Herein we review these studies including discussion of the functional significance of cohesin inactivation in tumorigenesis and potential therapeutic mechanisms to selectively target cancers harboring cohesin mutations.

• Korean Journal of Pharmacognosy
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• v.3 no.4
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• pp.187-197
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• 1972

In spite of the fact that the system of oriental medicine still remains in the realm of 'unproven-method of treatment', no one can deny that the oriental medicine is a rich source of idea and motivation for the discovery of new drug from natural sources. However, non-scientific, mystic hypothetical system of oriental medicine refuses to be revealed scientifically. For the purpose of drawing useful parameters for inductive reasoning of the system, a new approach which comprises statistical analyses of prescription was attempted in this study. One hundred and thirty two ginseng-compounds prescription in 'Bang-Yak-Hap-Pyon', one of the most popular formularies of oriental medicine in Korea, were analysed by multivariate analysis technique. The results revealed ginseng from many points of view, e.g., therapeutic indications, dose, and compatibility, etc. Among these, the most striking coincidence with scientific achievements of modern pharmacology, is the fact that the oriental medicine has characterized ginseng already from remote ancient times as neither a specific curative nor an aphrodisiac, but a non-specific adaptogenic drug for general infirmity.

• Mycobiology
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• v.48 no.1
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• pp.44-50
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• 2020

Calonectria pseudonaviculata and C. henricotiae are two closely related fungal species responsible for boxwood blight disease of ornamental shrubs (Buxus spp.) in the U.S. and Europe. A previous study has shown isolates of the latter species, which is restricted to Europe, to be less sensitive to tetraconazole, an azole fungicide. In this study, we have analyzed the CYP51 paralogs for polymorphism in 26 genomes, representing geographically disparate populations of C. pseudonaviculata (n = 19) and C. henricotiae (n = 7), from the U.S., Europe, Asia, and New Zealand. The presence of a CYP51A pseudogene and lack of a functional CYP51A paralog in all C. pseudonaviculata genomes examined is a novel discovery for fungi and could have implications for the evolution of resistance to antifungal chemicals.