• 천문학회보
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• 제38권2호
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• pp.40.2-40.2
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• 2013

Although galaxy mergers are thought to play an important role in forming elliptical galaxies, mergers in galaxy clusters have drawn less attention compared to mergers in field environments because galaxies with high peculiar velocities are unlikely to merge with each other. However, comparable fractions of merger features in cluster galaxies have been reported from deep imaging of Abell clusters, suggesting the relevance of mergers in the transformation of cluster early-type galaxies (Sheen et al. 2012). As a more direct approach to understanding the origin of tidal features in clusters, we perform hydrodynamic re-simulations on a cluster of galaxies. Based on mock observation images of the simulated cluster galaxies, we construct and analyze the cluster early-type galaxy sample in a consistent manner with Sheen et al. 2012. We find that the fraction of tidal feature from the simulated cluster is comparable to that of the observation. Evolutionary history of the galaxies with merger features shows that most of the mergers responsible for the merger features in the present originate from outside the cluster more than 2Gyrs ago. We also find that many of the galaxies with tidal features show correlations with subgroups in the cluster. All these results suggest that merger features in the cluster are due to preprocessing before accretion into the cluster.

• 한국동물학회지
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• 제22권3호
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• pp.115-124
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• 1979

경골어류 드렁허리와 가물치에서 젖산수소이탈효소의 세가지 동질사량체를 순수 정제하였다. 이들에 대한 항혈청을 얻어 젖산수소이탈효소와 면역화학적 반응을 실시하였다. 하부단위체의 활성자리는 항원결정군에 속해 있지 않으며, 항혈청내의 항체 또는 미지의 물질이 하부단위체의 하전을 변화시키며, 두 하부단위체는 공통의 항원결정군을 갖고 있음이 확인되었다.

• 한국실내디자인학회논문집
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• 제17권1호
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• pp.93-101
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• 2008

One of the big difference between Aalto and other modem architects lies in an attitude that Aalto went beyond the principle of dogmatic functionalism. As an architect of Northern Europe, Aalto made unique architecture that showed both the language of modem architecture and vernacular architecture. He presented the best example which showed modernity in architecture without losing the meaning of the context including site, region and cultural tradition. With this background, Aalto developed his own typological design approach. As Wolfsburg church was designed in his prime of time, it showed the origin and evolutionary process of religious architecture as well as general features of Aalto's design. Clustered site plan, dynamic space of interior, the adequate control of natural light are representative characteristics found in Aalto's religious architecture. Wolfsburg church also demonstrate these features in more specific way including the continuity of wall and ceiling that showed spatial dynamics, free opening of wall which reflects on functions, and careful adjust of natural light. As a result, Aalto showed his typological design strategy that added new design ideas to the accumulated design vocabularies in the design of Wolfsburg church.

• 한국자원식물학회:학술대회논문집
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• 한국자원식물학회 2002년도 제9차 국제심포지움 및 추계정기학술발표회
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• pp.13-14
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• 2002

Bottle gourd, Lagenaria siceraria, is one of the oldest cultivated plants. To bigin with, its fruit was used as a complete liquid bottle or container. It was a very widespread cultivated plant in prehistoric times, for example (there) is a report from Peru as early as between 13,000 B.C and 11,000 B.C. The dug-out finds in Japan proved to be about 95,000 years old according to the $^{14}$ C analysis. The bottle grourd was the most important plant before the invention of pottery in many areas of Asia, New Guinea, Polynesia, America, and Africa. I would like to suggest that there should be “The Bottle Gourd Age” prior to the Pottery Age.(중략)

• 한국수학사학회지
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• 제33권3호
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• pp.167-177
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• 2020

Cooperative behavior may seem contrary to the notion of natural selection and adaptation, but is widely observed in nature, from the genetic level to the organism. The origin and persistence of cooperative behavior has long been a mystery to scientists studying evolution and ecology. One of the important research topics in the field of evolutionary ecology and behavioral ecology is to find out why cooperation is maintained over time. In this paper we take a historical overview of mathematical models representing cooperative relationships from the perspective of mathematical biology, which studies population dynamics between interacting biological groups, and analyze the mathematical characteristics and meanings of these cooperative models.

• Journal of Plant Biology
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• 제36권2호
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• pp.141-149
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• 1993

Comparative morphology of winter buds of 16 species of gymnosperms which belong to six families and 13 genera was investigated. All the species examined except Taxaceae had bracts and ovuliferous scales in female buds, and the bract was fused with ovuliferous scale in various degrees. Comparison of the modern conifers with fossil ones in the position of ovule and structure of bract-scale complex suggested that Taxaceae should be placed in Coniferales, rather than treating as a distinct order. The disposition of bract surrounding the ovules of Cephalotaxus and Torreya indicated that the origin, of ovules had separate evolutionary line in spite of similar structure of female bud. The shape of microsporophyll in male bud was diverse among the species. The dehiscence of microsporangium was transverse in Abies and Tsuga, while longitudinal in other species. Descriptions and key to the species based on bud morphology were provided.

• Journal of Veterinary Science
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• 제24권6호
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• pp.78.1-78.6
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• 2023

Avian-origin H3N2 canine influenza A viruses (CIVs) have become enzootic in China and Korea and have sporadically transmitted to North America, causing multiple epidemics. We isolated six CIVs in Korea from CIV-infected patients during 2014-2017 and conducted whole genome sequencing and phylogenetic analyses. Results revealed that CIVs have circulated and evolved in Korea since the early 2000s and then diversified into a new clade, probably contributing to multiple epidemics in China, the USA, and Canada. Our findings bridge an evolutionary gap for understanding the global transmission of CIVs, emphasizing the significance of continuous monitoring of CIVs.

• 식물분류학회지
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• 제49권2호
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• pp.127-139
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• 2019

The purported four hybrid origins of Asplenium in Korea were tested based on morphological, cytological and DNA sequence data. Asplenium castaneo-viride, A. ${\times}$ uiryeongse, A. ${\times}$ montanus, and A. ${\times}$ kitazawae share several morphological characteristics with the Asian walking fern A. ruprechtii and related taxa as parents and show a sympatric distribution with the putative parents, raising the possibility of hybrid origins: A. castaneo-viride (A. ruprechtii and A. incisum), A. ${\times}$ uiryeongse (A. ruprechtii and A. pekinense), A. ${\times}$ montanus (A. ruprechtii, A. trichomanes, and A. incisum), and A. ${\times}$ kitazawae (A. ruprechtii and A. sarelii). We investigated flow cytometry and chloroplast DNA sequence data (rbcL, rps4-trnS, and rps4-trnS intergenic spacer) to clarify the hybridization and origin of each hybrid. In the flow cytometry analyses, A. ruprechtii shows diploid (2x) only, whereas A. castaneo-viride (3x, 4x), A. ${\times}$ uiryeongse (3x), A. ${\times}$ montanus (3x, 4x), and A. ${\times}$ kitazawae (2x, 4x) exhibit polyploidy, suggesting hybrid events along speciation. The rbcL and rps4-trnS and rps4-trnS intergenic spacer data suggest that A. ruprechtii is one the maternal ancestors of all four hybrids. In addition, the rps4-trnS and rps4-trnS intergenic spacer data indicate that A. incisum is also the maternal ancestor of A. ${\times}$ kitazawae and A. ${\times}$ montanus, proposing multiple hybridization events for these two hybrids. In A. ${\times}$ montanus, morphological features such as the leaf forms and sympatric distributions of the species also support the multimaternal hypothesis, but the morphological features of A. ${\times}$ kitazawae must be examined with consideration of hybrid events. To clarify the complex hybrid evolutionary lineages of the four Asplenium hybrids, further research with taxon sampling and molecular markers should be conducted.

• Journal of Microbiology and Biotechnology
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• 제20권9호
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• pp.1307-1313
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• 2010

An extracellular ${\alpha}$-amylase from Lactococcus lactis IBB500 was purified and characterized. The optimum conditions for the enzyme activity were a pH of 4.5, temperature of $35^{\circ}C$, and enzyme molecular mass of 121 kDa. The genome analysis and a plasmid curing experiment indicated that $amy^+$ genes were located in a plasmid of 30 kb. An analysis of the phylogenetic relationships strongly supported a hypothesis of horizontal gene transfer. A strong homology was found for the peptides with the sequence of ${\alpha}$-amylases from Ralstonia pikettii and Ralstonia solanacearum. The protein with ${\alpha}$-amylase activity purified in this study is the first one described for the Lactococcus lactis species, and this paper is the first report on a Lactococcus lactis strain belonging to the amylolytic lactic acid bacteria (ALAB).

• 한국한의학연구원논문집
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• 제14권3호
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• pp.49-56
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• 2008

Glehnia littoralis Fr. Schmidt et Miquel is an important medicinal plants in East Asian countries. This plant species naturally distributed in Korea, Japan, China, and Taiwan, but it is a rare plants living in the coastal dune in Korea. To investigate the genetic variation, genetic diversity and genetic evolutionary relationships of 14 different geographical G. littoralis, ITS sequence and random amplified polymorphic DNA (RAPD) were analyzed. On the basis of ITS sequences, it was clearly showed that the ITS1 and ITS2 sequences among 14 populations are identical regardless of geographical origin excepting 2 bp in pair-wise comparison of ITS1. Furthermore, RAPD results also showed that 14 different geographical G. littoralis produce various polymorphic patterns without critical relationship among neighboring regions. These combined results suggest that the geographical variation and genetic evolution of G. littoralis is stable and provide important information on genetic diversity, and conservation of this rare plant species in situ and ex situ.