• Genomics & Informatics
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• v.8 no.2
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• pp.86-89
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• 2010

Closely related species share large genomic segments called syntenic regions, where the genomic elements such as genes are arranged co-linearly among the species. While synteny is an important criteria in establishing orthologous regions between species, non-syntenic regions may display species-specific features. As the first step in cataloging human- or primate- specific genomic elements, we surveyed human genomic regions that are not syntenic with any other non-primate mammalian genomes sequenced so far. Based on the data compiled in Ensembl databases, we were able to identify 10 such regions located in eight different human chromosomes. Interestingly, most of these highly human- or primate- specific loci are concentrated in subtelomeric or pericentromeric regions. It has been reported that subtelomeric regions in human chromosomes are highly plastic and filled with recently shuffled genomic elements. Pericentromeric regions also show a great deal of segmental duplications. Such genomic rearrangements may have caused these large human- or primate- specific genome segments.

• Mycobiology
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• v.47 no.3
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• pp.261-272
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• 2019

Oomycetes are widely distributed in various environments, including desert and polar regions. Depending upon different habits and hosts, they have evolved with both saprophytic and pathogenic nutritional modes. Freshwater ecosystem is one of the most important habitats for members of oomycetes. Most studies on oomycete diversity, however, have been biased mostly towards terrestrial phytopathogenic species, rather than aquatic species, although their roles as saprophytes and parasites are essential for freshwater ecosystems. In this study, we isolated oomycete strains from soil sediment, algae, and decaying plant debris in freshwater streams of Korea. The strains were identified based on cultural and morphological characteristics, as well as molecular phylogenetic analyses of ITS rDNA, cox1, and cox2 mtDNA sequences. As a result, we discovered eight oomycete species previously unknown in Korea, namely Phytopythium chamaehyphon, Phytopythium litorale, Phytopythium vexans, Pythium diclinum, Pythium heterothallicum, Pythium inflatum, Pythium intermedium, and Pythium oopapillum. Diversity and ecology of freshwater oomycetes in Korea are poorly understood. This study could contribute to understand their distribution and ecological function in freshwater ecosystem.

• Journal of Integrative Natural Science
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• v.9 no.1
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• pp.23-27
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• 2016

Hepatitis B virus is the leading source of liver disorders and is a global health problem and needs advancements in its treatment against increasing problems. Recently five vanitaracin derivatives were isolated from the fungus Talaromyces species which have anti-Hepatitis B virus activity. Hence, in the present study, molecular docking was carried out with five vanitaracin derivatives isolated from Talaromyces species and three known inhibitors.The objective of this work is to study the interaction of newly isolated compounds and compare its interaction with known inhibitors. The docking results revealed that vanitaracin derivatives have good interactions and has better docking score with the Hepatitis B virus and suggest SER2, SER4 and ASP30 are important residues involved in interaction with the inhibitors. These result authenticates vanitaracin derivatives contributes to inhibitory activity of Hepatitis B virus to treat liver disorders.

• Korean Journal of Environmental Biology
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• v.37 no.1
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• pp.1-7
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• 2019

During a recent study to understand an interaction of Collembola community and their environmental factors, two species in the genus Folsomia, F. quadrioculata Tullberg 1871 and F. octoculata Handschin 1925, were found in the forest of South Korea. From 2013 to 2015, these two species were sampled from six mountains and F. quadrioculata or F. octoculata was the dominant species in 5 sampling sites among 6 sampling sites. F. quadriocualta and F. octoculata were found in litter of deciduous and pine forest, respectively. Therefore, the major tree species seems to be one of the important factors determining their habitat. F. quadiroculata is newly recorded from the Korean Peninsula and F. octoculata is redescribed based on new materials from South Korea.

• Journal of Species Research
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• v.10 no.4
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• pp.356-363
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• 2021

Heterotrophic nanoflagellates (HNFs, 2-20 ㎛ in size) are substantially capable of controlling bacterial abundance in aquatic environments, and microbial taxonomists have studied ecologically important and abundant HNFs for a long time. However, the classifications of HNFs have rarely been reported in Korea on the basis of morphology and 18S rDNA sequencing. Here, previously reported five HNFs from non-Korean habitats were isolated from Korean coastal seawater or intertidal sediments for the first time. Light microscopic observations and 18S rDNA phylogenetic trees revealed that the five isolated species were Cafeteria burkhardae strain PH003, Cafeteria graefeae strain UL001, Aplanochytrium minuta (formerly Labyrinthuloides minuta) strain PH004, Neobodo curvifilus strain KM017 (formerly Procryptobia sorokini), and Ancyromonas micra (formerly Planomonas micra) strain IG005. Being morphologically and phylogenetically indistinct from its closest species, all isolates from Korea were therefore regarded as identical species detected in other countries. Thus, this result indicates an expansion of known habitats that range from those of the five isolates in natural ecosystems on Earth.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.21 no.4
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• pp.11-23
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• 2018

The purpose of this study is to identify the ecological characteristics and biological interactions between species of the abandoned rice paddy field in mountainous areas and to suggest a management strategy for stable food chain formation and biodiversity enhancement. The study site is located in Uldae wetland of Songchu district Bukhansan National Park, site characteristics and biological habitat characteristics were identified through site survey and literature survey. With regard to physical environment, among geographical features, the Uldae Wetland and the neighborhood inside the basin was a gently sloping area($5{\sim}15^{\circ}$). And 64.0% of basin faced the north. With regard to water environment, the Uldae Wetland was wetland of rainfed paddy field depending on precipitation and the system of stream flowing into the wetland from valley. According to the results of examining flora in plant ecology, in general, they were herbaceous wetland species. 88.6% of existing plants inside the Uldae Wetland basin was a forest in the mountain. And Quercus spp. community and Pinus densiflora community accounted for 64.6% of that, and was dominant. Except for that, Salix koreensis community was distributed. The existing vegetation of Uldae Wetland inhabited wetland species and terrestrialization indicator species, and it was thought that partial terrestrialization inside the Uldae Wetland was in progress after the discontinuation of paddy cultivation, such as the expansion of Salix koreensis distribution area. In the status of appearing faunae in the Uldae Wetland with regard to wildbirds of appearing principal species, The Uldae wetland was based on a abandoned rice paddy field various wildlife, and was a wildlife feeding, spawning, and resting place. The water environment was an important factor in maintaining the wetland living creatures function, habitat of waterbirds and benthic macroinvertebrates, amphibians and odonate are spawning ground and habitat, it was affecting the vegetation ecosystem based on wetlands. In order to maintain the diversity of wildlife, it was important to maintain smooth water supply and water level. A stable food chain will be formed and the Uldae wetland biodiversity will be abundant by establishing the relationship between the species of Uldae wetland, which is abandoned rice paddy field, and the habitat environment favored by species belonging to the ecosystem stepwise linkage. The ecological characteristics of the Uldae wetlands and the relation between the species were analyzed and the environmental conditions were reflected in the planning and management plan of Uldae wetland ecology.

• Korean Journal of Environment and Ecology
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• v.38 no.3
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• pp.324-337
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• 2024

Aquatic macrophytes are important factors in determining species diversity and abundance of cladocerans, but the effects of cladocerans on plant species composition or structure have not been fully considered. In South Korea, wetlands and reservoirs that are prone to covering aquatic macrophytes are scattered across the country, so it is necessary to consider on aquatic macrophytes study, when aquatic animals including cladoceran were studied. in this study, the species and abundance of cladocerans community in six microhabitat types are investigated, and based on these results, habitat conservation and efficient management are suggested. The high species numbers and abundance of cladocerans communities were found in mixed plant communities consisting of free-floating, floating-leaved, and submerged plants. The inclusion of submerged plants in plant communities contributes significantly to the complexity of habitat structures, and may increase species and abundance of cladocenran communities. This can be compared to a plant community consisting only of free-floating and floating-leaved plants in the absence of submerged plants, thereby identifying the efficiency of submerged plants. In the mixed plant communities, species diversity was the highest due to the emergence of cladoceran species (Graptoleveris testudinaria, Ilyocryptus spinifer, and Leydigia acanthococcides) absent from other plant communities. The gradual increase in the biomass (g) of submerged plants in the mixed plant communities significantly increased the species numbers and abundance of cladoceran communities (p<0.05). This is strong evidence that the increase of submerged plants in mixed plant communities has a positive effect on efficiency as a habitat for cladocerans. Although submeged plants do not contribute significantly to their landscape/aesthetic value because they are submerged in water, they have the effect of increasing species diversity in terms of biology, so they should be considered important when creating/restoring wetlands.

• The Journal of Korean Medicine
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• v.25 no.4
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• pp.147-151
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• 2004

Objective : Angelica species are some of the most medicinally important materials in Oriental medicine. This study was performed to determine if Angelica species could be identified by genetic analysis and to verify Pyrosequencing analyses, which were used to assess genetic variation. Methods : The DNAs of Angelica acutiloba, Angelica gigas and Angelica sinensis were extracted. We have investigated the typing of single-base variations of Angelica species in DNA by using Pyrosequencing. Results : Angelica gigas showed a different pattern compared with Angelica acutiloba and Angelica sinensis. The peak of Angelica gigas was very weak in the second C nucleotide base compared with that of the others. The peak of Angelica acutiloba was present in the fourth C nucleotide base compared with that of the others. From these results we verified that our Angelica species-specific sequencing primer was well designed. Conclusion : Pyrosequencing analysis might be able to provide the identification of the Angelica species.

• 한국연소학회:학술대회논문집
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• 2014.11a
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• pp.5-7
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• 2014

A skeletal mechanism of coal combustion was derived from a detailed coal combustion kinetic mechanism through an importance analysis of chemical pathways. The reduction process consists of roughly two parts. The first process is performed based on a connectivity analysis between species. In this process, DRGEPSA is chosen for reduction process. Strongly connected species and related reactions from the important species set as start species by the operator are sorted into the reduced mechanism. About 70% of species and reactions can be removed with a limited accuracy loss. Subsequently the second reduction process, CSP, is performed. This method focuses on an importance of each reaction and can reduce a volume of mechanism appropriately. Through these analyses, a skeletal mechanism is generated that is including 65 species and 150 reactions. The generated skeletal mechanism is verified through a comparison with the detailed mechanism in the homogeneous reactor model of CHEMKIN-PRO under wide range of conditions. The generated mechanism can give an advantage in the analysis of coal combustion characteristics in detail in large scale simulations such as LES and DNS.

• Journal of Ecology and Environment
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• v.32 no.3
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• pp.183-189
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• 2009

This research focused on the effects of fragmentation on moth diversity in an agricultural land-scape by comparing moth species richness and abundance between hillocks and young secondary forests. We examined five sites from the southwestern part of South Korea: three sites from hillock forest and two from secondary forest. We collected moths bi-weekly from April to October for a 2-year period (2006-2007) with a UV light trap that usually attracts moths within 30 meters. Tree species richness and abundance in $20m{\times}20m$ plots at each moth sampling site showed a substantial difference in tree diversity between the two types of forest habitats. The total abundance and richness of moth species were higher in secondary forests (541 species with 4,998 individuals) than in hillock forests (423 species with 3,913 individuals), irrespective of the distance among the sites. An ordination analysis with NMDS showed that habitat is the most important factor of grouping sites. The food preferences of the dominant moth species i,n each habitat were closely related to the habitat type.