• 한국전산유체공학회:학술대회논문집
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• 2008.10a
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• pp.84-91
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• 2008

Generalized hydrodynamic (GH) theory for multi-species gas and the computational models are developed for the numerical simulation of hypersonic rarefied gas flow on the basis of Eu's GH theory. The rotational non-equilibrium effect of diatomic molecules is taken into account by introducing excess normal stress associated with the bulk viscosity. The numerical model for the diatomic GH theory is developed and tested. Moreover, with the experience of developing the dia-tomic GH computational model, the GH theory is extended to a multi-species gas including 5 species; $O_2,\;N_2$, NO, O, N. The multi-species GH model includes diffusion relation due to the molecular collision and thermal phenomena. Two kinds of GH models are developed for an axisymmetric flow solver. By compar-ing the computed results of diatomic and multi-species GH theories with those of the Navier-Stokes equations and the DSMC results, the accuracy and physical consistency of the GH computational models are examined.

• Korean Journal of Environmental Biology
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• v.39 no.3
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• pp.399-405
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• 2021

Until now, five species (Meghimatium bilineatum, M. fruhstorferi, Limax flavus, L. marginatus, Deroceras reticulatum) in three genera of families Philomycidae and Limacidae have been reported in Korea. Philomycidae is a family of air-breathing land snails. Meghimatium hongdoensis sp. nov. is described based on its middle size (60-80 mm in body length), its body coloration (dark-red yellow), no dorsal with streaks, its genitalia, and 16rDNA sequence analysis. Specimens of this new species were collected from Hongdo island, Sinan-gun, Jeollanam-do, Korea. This species is only known from the type locality at Hongdo to date. It could be found in high-humidity sites. Meghimatium uniforme (Laidlaw 1937) was the first one reported in Korea. It was also collected from Gageodo island, Sinan-gun, Jeollanam-do, Korea. In this study, morphological characteristics including their radula and genital structures of these two species were described. Preliminary results of mitochondrial 16S rDNA sequencing and phylogenetic analyses indicated that these species belonged to the Korean clade.

• Animal cells and systems
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• v.5 no.4
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• pp.275-281
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• 2001

The zoea1 stages of Philyra kanekoi Sakai, 1934 were obtained by laboratory rearing. Three zoeal stages were described and illustrated in detail. Zoeal morphology was compared with those of other described species of the family Leucosiidae. Morphological comparisons with congeneric species revealed that zoeas of P. kanekoi were more similar to those of P. pisum and P. platychira than to other Philyra. The present material could be distinguished from other Philyrinae species by having no dorsal carapace spine, a spinous tip of the antenna, and no chromatophore on the base of a dorsal carapace spine. Within the family Leucosiidae, the zoeas of three Philyra (P. kanekoi, P. pisum and P. platychira) showed the greatest affinities with Leucosia sima and L. pubescens (Leucosiinae), and the number of setae on the basipod of the first maxilliped could be very useful characterisitcs for indentification between Philyra and Leucosia zoeas.

• The Korea Journal of Herbology
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• v.39 no.3
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• pp.11-21
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• 2024

Objective : For the purpose of developing Korean Primulaceae plants, the literature published so far have been thoroughly investigated to prepare this article. Methods : Books and research papers about Herbology which published at Korea and other countries were examined. Results : The results of this study were as follows: 1. A total of 8 genera and 30 species of Primulaceae was found in the Korea, among which 4 genera and 9 species (approximately 30%) were medicinal plants. 2. Among Korean Primulaceae plants, Lysimachia was the most with 11 species. 3. Among medicinal plants, Lysimachia was the most with 5 species, followed by 1 species of Anagallis, 1 species of Primula, and 2 species of Androsace. 4. The domestic distribution of medicinal plants was 4 species in the north part, 7 species in the central part, 7 species in the south part, and 7 species in Jeju island. 5. Among the medicinal parts, the whole body was used the most with 9 species. Among the property flatness property was the most whith 10 species. And among the flavors, bitter taste was the most with 13 species. 6. Lung meridian channel was the most with 3 species. The effect of reducing swelling was the most with 10 species. 7. No toxic drugs have been reported yet. Conclusion : There were totaled to 8 genera and 30 species in Primulaceae in Korea and among them medicinal plants are 4 genera, 9 species, some 30% in total.

• Journal of Forest and Environmental Science
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• v.34 no.2
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• pp.173-175
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• 2018

Stem cuttings of three Rubus species native to Korea were treated by two commercial root stimulation formula for propagation. Differences among the species was obvious, toot was induced relatively easily on R. hongnoensis. Fifty percent of stem rooted without any treatment on this species and two stimulators was effective to increase the root induction. On the other hand, two other species, R. schizostylus and R. ribisoideus, had very low percent of rooting. Treatment using root stimulators was effective but still lower than that of R. hongnoensis. Root induction was not influence by the medium that resulted no differences between two media.

• Korean Journal of Pharmacognosy
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• v.4 no.2
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• pp.75-82
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• 1973

In Korea, two species of Ho-chang-Ho-chang $(Polygonum\;cuspidatum \;S_{IEB}.\;et\;Z_{UCC}.)$ and Wang-Ho-chang $(Polygonum \;sachalinense\;F_R.\;S_{CHM}.)$-had been identified, but the components of the leaves of Polygonum species growing in Korea had never been reported. The authors examined the anatomical characteristics of Korean Polygonum species, identified the flavonoids contained in their leaves and obtained the following results: Korean Polygonum species should be divided into three species: $Polygonum\;cuspidatum\;S_{IEB}.\;et\;Z_{UCC}.,\;P. \;sachalinense\;F_R.\;S_{CHM}\;and\;P.\;elliptica\;M_{IGO}$. The last one was illustrated in the report. P. cuspidatum contained reynoutrin and quercitrin, but no isoquercitrin could be identified. P. sachalinense also contained both reynoutrin and quercitrin. P. elliptica, which had never been studied, included the same flavonoids.

• The Korean Journal of Ecology
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• v.21 no.5_2
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• pp.557-565
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• 1998

The occurrence and distribution of dictyostelid cellualr slime molds were investigated in forests of Mt. Paektu. Fourteen species were isolated from forest soils of thirteen sites as follows Dictyostelium minutum, D. brefeldianum, D. crassicaule, D. capitatum, D. mucoroides var. stoloniferum, D. macrocephalum, D. mucoroides, D. septentrionalis, D. purpureum, D. aureo-stipes, P. violaceum, P. pallidum and two unidentified speceis. Mean total clones and species found were 4,415.69 No./g and 2.92, respectively. Dominant species were D. minutum, D. brefeldianum and D. crassicaule in this study area, and first widespread species was D. minutum. All sepecies that found in Mt. Paektu were isolated from forests of South Korea. But dominant species was different from those of South Korea. Total clones and species were more in subalpine Eurya japonica than in low elevated abies nephrolepis. It was thought that distribution of dictyostelids was related to soil microenvironments by vegetation, not or not more elevation.

• International Journal of Industrial Entomology and Biomaterials
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• v.24 no.1
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• pp.41-47
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• 2012

The Scarites aterrimus (Coleoptera: Carabidae) dwells exclusively on coastal sandy dunes. Previously, we investigated the nation-wide magnitude and nature of genetic diversity of the species using mitochondrial COI gene and found moderate to low magnitude of sequence diversity, the presence of closely related haplotypes, and relatively high gene flow estimate. Based on these observations we concluded that the species had no historical barriers that bolster genetic subdivision and possible population decline. In this study, we additionally sequenced mitochondrial COII gene from 23 individuals collected from 9 Korean localities to confirm previous findings. Sequencing of 688 bp COII gene provided 5 haplotypes ranging in sequence divergence from 0.145% to 0.291% (1 ~ 2 bp), further confirming low sequence divergence of the species. Gene flow estimates and genetic diversity estimates also support the previous findings that there had been no historical barriers that bolster genetic subdivision.

• Parasites, Hosts and Diseases
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• v.52 no.1
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• pp.35-40
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• 2014

A survey was performed to investigate the infection status of freshwater fish with zoonotic trematode metacercariae in Phnom Penh and Pursat Province, Cambodia. All collected fish with ice were transferred to our laboratory and examined using the artificial digestion method. In fish from Phnom Penh, 2 kinds of metacercariae (Opisthorchis viverrini and Haplorchis yokogawai) were detected. O. viverrini metacercariae were positive in 37 (50.0%) of 74 fish in 11 species (average no. metacercariae/fish, 18.6). H. yokogawai metacercariae were detected in 23 (57.5%) of 40 fish in 5 species (average no. metacercariae/fish, 21.0). In fish from Pursat Province, 5 kinds of metacercariae (O. viverrini, H. yokogawai, Haplorchis pumilio, Centrocestus formosanus, and Procerovum sp.) were detected; O. viverrini metacercariae (n=3) in 2 fish species (Henicorhynchus lineatus and Puntioplites falcifer), H. yokogawai metacercariae (n=51) in 1 species (P. falcifer), H. pumilio metacercariae (n=476) in 2 species (H. lineatus and Pristolepis fasciata), C. formosanus metacercariae (n=1) in 1 species (H. lineatus), and Procerovum sp. metacercariae (n=63) in 1 species (Anabas testudineus). From the above results, it has been confirmed that various freshwater fish play the role of a second intermediate host for zoonotic trematodes (O. viverrini, H. yokogawai, H. pumilio, C. formosanus, and Procerovum sp.) in Cambodia.

• Animal cells and systems
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• v.16 no.2
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• pp.135-144
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• 2012

$Dendronephthya$ $castanea$ Utinomi, 1952 is a member of the family Nephtheidae, and dominates shallow waters adjacent to the southern part of Jejudo Island, Korea. This species is a gonochoric internal brooder with a sex ratio of 1:1, and releases planulae around the time of the full and new moon from July to September, when the seawater temperature peaks. The gametogenic cycle is annual, and oogenesis (12 months) is longer than spermatogenesis (4-5 months). No difference in reproductive features including sexuality, sex ratio, gametogenesis and gametogenic cycles was found between the sympatric species $D.$ $castanea$ and $D.$ $gigantea$, and there was no temporal reproductive isolation. Investigation of the morphological taxonomy and molecular biology of these species indicates that they have very similar or identical traits, suggesting an absence of speciation and a need for taxonomic reclassification.