• Journal of The Korean Society of Grassland and Forage Science
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• v.18 no.2
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• pp.143-150
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• 1998

Six field bean (GI-vcine soza S and Z ) plants were examined for their genetic polymorphisms and intraspecific variations using randomly amplified polymorphic DNA(RAPD) markers. In RAPD analysis of 5 random primers (Rp-1, Rp2, Rp-3, Rp-4, Rp-5), 30 of total 155 bands obtained kom 5 primers were polymorphic and sizes of polymirphic band ranged between 0.5 and 3.0 kb. Number of bands amplyfied per primer was varied from 2 to 11 and average number was 6.0. Genetic variation of intraspecies in the samples of six region was ranged behveen 11 to 25 percent, and genetic similarity among intraspecies was ranged from 0.69 to 0.78. In pairwise genetic similarity test of six field bean plants, Mun and Hoj showed highest coefficient of genetic similarity as 0.67, whereas Sin and Hoj was lowest as 0.45. According to the genetic similarity, the level of intraspecific variation is higher than that of regional distance in GI-vcine soza.

• Bulletin of the Korean Mathematical Society
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• v.49 no.6
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• pp.1255-1262
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• 2012

A type of delayed Lotka-Volterra competition reaction-diffusion system is considered. By constructing a new Lyapunov function, we prove that the unique positive steady-state solution is globally asymptotically stable when interspecies competition is weaker than intraspecies competition. Moreover, we show that the stability property does not depend on the diffusion coefficients and time delays.

• Animal cells and systems
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• v.4 no.1
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• pp.1-7
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• 2000

The genus Dendronephthya, generally known as soft corals, is reported as an abundant and variable taxon. They mostly distribute in warmer waters of the Undo-Pacific Ocean region including Korea. In spite of their abundance and ecological importance as habitats of marine organisms, there are difficulties in the study of their identification and systematics because they have morphological variabilities and limited taxonomec characters. To resolve the problems, we attempted to elucidate the genetic relationships in the genus Dendronephthya by using random amplified polymorphic DNA (RAPD) analysis. This study was based on eight dendronephthian species and one Alcyoniidae species, Alcyonium gracillimum, as an outgroup. The results from all analysis suggest that they could be classified into four groups by the growth form and the anthocodial grades as follows: the first one,D. putteri and D. suensoni with the divaricate form and VI grade; the second one,D. sp.1 and D. sp.2 with the divaricate form and III or IV grade; the third one, D. gigantea and D. aurea being closer than D. spinifera with the glomerate form and III grade; the last one, D. castanea related to D. gigantea rather than D. putteri with the umbellate form and IV grade. Moreover, the divaricate form was separated from the group of the glomerate and umbellate form. At the intraspecies level, the types of the D. castanea, D. gigantea and D. spinifera were separated depending on the feature of spicules in the polyp head, and the coloration could not influence genetic variation. From this study, we can confirm that their morphological characters are compatible with the genetic variation, also RAPD analysis is a very useful method for resolving the systematic relationships of den-deonephthians.

• Korean Journal of Agricultural Science
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• v.33 no.1
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• pp.35-41
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• 2006

This study was conducted to investigate the developmental ability of interspecies cloned embryos after nuclear transfer of goat fetal fibroblast cells into porcien oocytes. Recipient porcine and goat oocytes were obtained from slaughterhouse and matured in vitro according to established protocols. Enucleation was accomplished by aspirating the first polar body and cytoplasm and a single donor cell was individually microinjected into vitelline space of the enucleated oocyte. The reconstructed oocytes were electrically fused with 0.3M mannitol fusion medium. After electro-fusion, interspecies reconstituted embryos were cultured in PZM-3 for 7 days. In porcine interspecies nuclear transfer with goat fetal fibroblast cells, the cleavage rate of reconstituted embryos were 58.9% which was no significant different from that in porcine nuclear transfer embryos (67.4%). However, the developmental rate into blastocyst stage was 5.4% in interspecies nuclear transfer which was significantly lower than that in porcine intraspecies nuclear transfer (13.6%). When the developmental ability of porcine interspecies nuclear transfer with goat cells was compared with goat intraspecies nuclear transfer, the cleavage rate of embryos were 59.2% and the developmental rate into morular and blastocyst stage was 13.6% in interspecies nuclear transfer which were significantly lower than those in intraspecies nuclear transfer embryos. This result indicated that porcine interspecies nuclear transfer with goat fetal fibroblast cells showed the developmental potential in vitro with lower cleavage and developmental rate compared with intraspecies nuclear transfer.

• Mycobiology
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• v.43 no.4
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• pp.444-449
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• 2015

Arbuscular mycorrhizal fungi (AMF) are ubiquitous in the rhizosphere and form symbiotic relationships with most terrestrial plant roots. In this study, four strains of Rhizophagus clarus were cultured and variations in their growth characteristics owing to functional diversity and resultant effects on host plant were investigated. Growth characteristics of the studied R. clarus strains varied significantly, suggesting that AMF retain high genetic variability at the intraspecies level despite asexual lineage. Furthermore, host plant growth response to the R. clarus strains showed that genetic variability in AMF could cause significant differences in the growth of the host plant, which prefers particular genetic types of fungal strains. These results suggest that the intraspecific genetic diversity of AMF could be result of similar selective pressure and may be expressed at a functional level.

• Korean Journal of Microbiology
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• v.26 no.4
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• pp.298-304
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• 1988

Antibiotic resistance plasmids (RP4, pMG1, R679 and R91-5) were used as primary selective markers to detect the fusants in Pseudomonas spp. By using plasmid marker, clones containing both plasmids of parental strains were obtained as fusants by direct selection. The spheroplast fusion was occured not only between strains of interspecies, but also between strains of intergenus such as Pseudomonas and E. coli. The frequencies of fusant formation were variable from $2.8\times 10^{-1}$ to $6.0\times 10^{-4}$ -4/. In addition, chromosomal recombinants were formed among the clones with both parental plasmids in frequencies of 0.44-1.3%. The fusant formation frequency between interspecies of intraspecies was not different markedly, but stability of plasmids in fusants correlated with the phylogenic smilarity of the parental strains.

• Animal Systematics, Evolution and Diversity
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• v.20 no.1
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• pp.63-71
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• 2004

The clustering analysis and comparison of male genitalia of Silpha perforata complex were carried out to decide the taxonomic status of the population from Jejudo Is., Korea. One hundred and five individuals from Korea, Japan, and China were examined for the present study. Based on the result, the population of Jejudo Is. was treated as intraspecies of Silpha perforata with a morphological variation.

• Korean Journal of Veterinary Research
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• v.36 no.4
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• pp.773-782
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• 1996

Sixty wild rate (fifty eight of Rattus norvegicus and two R rattus) were caught from Seoul, Kyonggi, Kangwon, Honam, and Yongnam areas between August and October 1992. From liver homogenates of the wild rats, isoenzyme patterns were analysed by starch gel electrophoresis. Using 9 enzyme systems, eight electrophoretic types were identified among wild rats with genetic diversity per locus between 0.00 and 0.49 (Mean 0.15). R rattus from Kyonggi (Kanghwa) and Kangwon (Cholwon) were distinct from R norvegicus from nine regions with 0.581 in genetic divergence. Therefore genetic divergence was different not only in interspecies(0.581) but also in intraspecies(0.111~0.375). These data suggested that isoenzyme electrophoresis could be used as a potential application in taxonomic studies of wild rats.

• Parasites, Hosts and Diseases
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• v.51 no.1
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• pp.37-42
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• 2013

Taeniasis is prevalent in all regions of Thailand, except the South. Infections were more frequently found in males than females of any age from 7-83 years. Taenia saginata is the most common species throughout the country. Taenia asiatica was reported only in the province of Kanchanaburi in the Central region. Co-infections, with Taenia solium and T. asiatica or T. solium and T. saginata, were found. Hybridization between T. asiatica and T. saginata is evidence that co-infection is never found between these 2 species. Finding more than 1 worm in a single patient was not entirely rare. Genetic variation was found without correlation to its geographic distribution in T. saginata, whereas no variation was found in T. asiatica.

• Journal of Species Research
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• v.10 no.2
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• pp.142-153
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• 2021

Algal genomics approaches provide a massive number of genome/transcriptome sequences and reveal the evolutionary history vis-à-vis primary and serial endosymbiosis events that contributed to the biodiversity of photosynthetic eukaryotes in the eukaryote tree of life. In particular, phylogenomic methods using several hundred or thousands of genes have provided new insights into algal taxonomy and systematics. Using this method, many novel insights into algal species diversity and systematics occurred, leading to taxonomic revisions. In addition, horizontal gene transfers (HGTs) of functional genes have been identified in algal genomes that played essential roles in environmental adaptation and genomic diversification. Finally, algal genomics data can be used to address the pangenome, including core genes shared among all isolates and partially shared strain-specific genes. However, some aspects of the pangenome concept (genome variability of intraspecies level) conflict with population genomics concepts, and the issue is closely related to defining species boundaries using genome variability. This review suggests a desirable future direction to merge algal pangenomics and population genomics beyond traditional molecular phylogeny and taxonomy.