• Korean Journal of Materials Research
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• v.18 no.4
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• pp.199-203
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• 2008

High-efficiency phosphorescent organic light emitting diodes using TCTA-TAZ as a double host and $Ir(ppy)_3$ as a dopant were fabricated and their electro-luminescence properties were evaluated. The fabricated devices have the multi-layered organic structure of 2-TNATA/NPB/(TCTA-TAZ) : $Ir(ppy)_3$/BCP/SFC137 between an anode of ITO and a cathode of LiF/AL. In the device structure, 2-TNATA[4,4',4"-tris(2-naphthylphenyl-phenylamino)-triphenylamine] and NPB[N,N'-bis(1-naphthyl)-N,N'-diphenyl-1,1'-biphenyl-4,4'-diamine] were used as a hole injection layer and a hole transport layer, respectively. BCP [2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline] was introduced as a hole blocking layer and an electron transport layer, respectively. TCTA [4,4',4"-tris(N-carbazolyl)-triphenylamine] and TAZ [3-phenyl-4-(1-naphthyl)-5-phenyl-1,2,4-triazole] were sequentially deposited, forming a double host doped with $Ir(ppy)_3$ in the [TCTA-TAZ] : $Ir(ppy)_3$ region. Among devices with different thickness combinations of TCTA ($50\;{\AA}-200\;{\AA}$) and TAZ ($100\;{\AA}-250\;{\AA}$) within the confines of the total host thickness of $300\;{\AA}$ and an $Ir(ppy)_3$-doping concentration of 7%, the best electroluminescence characteristics were obtained in a device with $100\;{\AA}$-think TCTA and $200\;{\AA}$-thick TAZ. The $Ir(ppy)_3$ concentration in the doping range of 4%-10% in devices with an emissive layer of [TCTA ($100\;{\AA}$)-TAZ ($200\;{\AA}$)] : $Ir(ppy)_3$ gave rise to little difference in the luminance and current efficiency.

• Proceedings of the Korean Society of Sericultural Science Conference
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• 1997.06a
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• pp.73-101
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• 1997

Baculoviruses are characterized by large double-stranded circular DNA genomes and rod-shaped enveloped virions. Bombyx mori nucleopolyhedrovirus(BmNPV) is a major pathogen, which causes severe damage in sericulture. Currently, BmNPV is recogtnized as an improtant tool in molecular biology, especially for expression of useful genes in B.mori cells and silkworm larvae. Our laboratories have focused on the studies of the molecular mechanisms of BmNPV replication and the application of BmNPV to agriculture and medicine. The entire nucleotide sequence of the BmNPV genome has recently determined. The BmNPV genome possessed 135 putative genes and 7 homologous repeated sequence (hrs) regions. Relatively little space, a few to a few hundred base-pairs, was observed between the open reading frames and hrs. Termination codons often overlapped. These results showed a compactly packde BmNPV genome. Based on comparative sequence analyses, we speculated that the ancestor of BmNPV was a baculovirus similar to Autographa californica NPV(AcNPV). The function of the BmNPV genes were characterized by gene deletion analysis; p35 was found to be involved in blocking apoptosis and cysteine proteinase was found to be involved in horizontal virus transmission by degrading viral-infected larval host. By AcNPV and BmNPV coinfection experiments, we identified a BmNPV gene involved in expanding host specificity of AcNPV. The identified gene was likely encoded a DNA helicase based on the amino acid sequence analysis; a few amino acid substitutions in the putative DNA helicase gene resulted in the expansion of host range of AcNPV. These findings indicate that BmNPV evolved within a short period from an AcNPV-like ancestral virus due to rapid evolution including specific amino acid substitutions and gene deletions/insertions.

• Journal of Arbitration Studies
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• v.29 no.2
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• pp.35-63
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• 2019

Since imposing Performance Requirements (PRs) on investors have been conducted as a means to protect a host state's domestic industry in the short run, with its effect on improving the international balance of payments, it has been implemented mostly in developing countries. From the viewpoint of investors, however, PRs hinder free competition and investment activities and have the effect of distorting international trade activities; therefore, they are expected to bring detrimental effects on the host state's economic development in the long run. PRs provided by International Investment Agreements (IIAs) and WTO-TRIMs, too, included many abstract regulations which are grounded on the host state's economic efficiency in the past; however, those PRs are gradually being more concretely specified, shifting to a form of prohibition with the goals of increasing the protection on investors and realizing investment liberalization. Accordingly, when Korea freshly concludes IIAs or revises them afterwards, one should focus more on following the points regarding PRs. First, to protect Korean companies' investment activities, it is advantageous to list the contents of prohibited PRs extensively and concretely and create a stipulation. Second, it is necessary to list the contents of the PRs prohibited and add the phrases for prohibiting "any other similar requirements" explicitly, as well so as to cover the PRs that can appear newly. Third, as in the cases associated with PRs, issuable matters are mostly either the range of applying PRs or the conditions of applying them (relevance or detrimental effects); therefore, it is necessary to classify the cases accumulated by issues and analyze them thoroughly. In conclusion, as this study has analyzed the theoretical characteristics of PRs provided in IIAs and related cases and suggests exquisite theory regarding PRs, it not only lays fundamental grounds for follow-up research but also gives useful and practical guidelines for the parties concerned and the arbitrators according to the ISDS procedure.

• Korea Trade Review
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• v.41 no.5
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• pp.305-323
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• 2016

The scope of umbrella clause is very important because it is possible to extend or reduce the range of protection of the investment. Umbrella clause stipulated in the majority of BIT is often controversial, since there is no established criteria for the scope. So, this study considered ICSID arbitration cases related to the scope of umbrella clause. There are two different approaches for the scope of umbrella clause by arbitral tribunals. First, all of the disputes on the investment contract elevated to the disputes on the BIT. And umbrella clause can be applied that the host state entered into investment contract not only as a sovereign but also as a merchant. Second, all of the claims on the investment contract don't elevate to the claims on the BIT. Umbrella clause can be applied only if the host state violates the protected investment contractual rights and obligation under the BIT. And umbrella clause can be applied that the host state entered into investment contract as a sovereign but not as a merchant. Therefore, this study suggests to concretely specify the scope of umbrella clause under the BIT. And it is necessary to improve predictability by establishing continual database of the scope of umbrella clause and to prepare for investment disputes related to the scope of umbrella clause.

• The Plant Pathology Journal
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• v.39 no.4
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• pp.384-396
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• 2023

Colletotrichum acutatum species complex is one of the most important groups in the genus Colletotrichum with a high species diversity and a wide range of host plants. C. acutatum and related species have been collected from different plants and locations in Korea and deposited into the Korean Agricultural Culture Collection (KACC), National Institute of Agricultural Sciences since the 1990s. These fungal isolates were previously identified based mainly on morphological characteristics, and a limitation of molecular data was provided. To confirm the identification of species, 64 C. acutatum species complex isolates in KACC were used in this study for DNA sequence analyses of six loci: nuclear ribosomal internal transcribed spacers (ITS), betatubulin 2 (TUB2), histone-3 (HIS3), glyceraldehyde3-phosphate dehydrogenase (GAPDH), chitin synthase 1 (CHS-1), and actin (ACT). The molecular analysis revealed that they were identified in six different species of C. fioriniae (24 isolates), C. nymphaeae (21 isolates), C. scovillei (12 isolates), C. chrysanthemi (three isolates), C. lupini (two isolates), and C. godetiae (one isolate), and a novel species candidate. We compared the hosts of KACC isolates with "The List of Plant Diseases in Korea", previous reports in Korea and global reports and found that 23 combinations between hosts and pathogens could be newly reported in Korea after pathogenicity tests, and 12 of these have not been recorded in the world.

• International Journal of Industrial Entomology and Biomaterials
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• v.5 no.2
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• pp.141-151
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• 2002

The success of sericulture industry in India is mainly attributed to the well-planned annual sericultural activity and the systematic implementation of pest preventive and control measures. The insect spectrum of silkworm and its food plants is complex and plays a major role in limiting the production of silk. Insects cause extensive damage to plant whereas predators and parasites either kill the silkworm larvae or force them to spin flimsy cocoons. Unilateral control measure against this pest is mainly based on the use of synthetic organic insecticides. Though these approaches initially paid rich dividends, the undesirable consequences soon surfaced. Insecticide induced resurgence of gall midges, leafhopper, leaf roller, secondary pest out breaks and development of pest biotypes has led to realization of Integrated Pest Management in sericulture. Various components of IPM, viz. Host plant resistance, cultural practices, biological control, chemical control and integrating them at various technological levels have been studied. Sources of host plant resistance have been identified for some of the major insect pests. High yielding mulberry variety has been propagated and their resistances towards major pests have been recorded. Cultural practices like pruning, pollarding, judicious use of nitrogen, optimum spacing and weed management have preyed to be the powerful tools in containing pests. Natural control over the pest population build- up exerted by the wide range of parasitoids, predators and pathogens has been well documented with identification of natural enemies and studies on their potential. Augmentation, through inoculation or inundative releases of parasitic arthropods, is the most direct way of increasing the numbers of these beneficials in sericulture.

• Journal of Microbiology and Biotechnology
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• v.27 no.12
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• pp.2151-2155
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• 2017

Bacteriophages have gained substantial attention as biocontrol and biorecognition agents, substituting antibodies. In this study, a Salmonella Enteritidis-specific bacteriophage, KFS-SE1, was isolated, identified, and characterized. This Siphoviridae phage infects S. Enteritidis with high specificity. This phage is highly stable under various pH (5-11), temperature ($4-60^{\circ}C$), and organic solvent conditions. The KFS-SE1 genome consisted of 59,715 bp with 73 predicted open reading frames and 57.14% GC content; it had a complete set of genes required for phage reconstruction. Comparative phylogenetic analysis of KFS-SE1 revealed that it was very similar to the other Salmonella phages in the Siphoviridae family. These characteristics suggest that KFS-SE1 with its high specificity and host lysis activity toward S. Enteritidis may have various potential applications.

• Journal of Environmental Health Sciences
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• v.28 no.5
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• pp.102-105
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• 2002

The gills of seven black rockfish, Sebastes melanops collected from Hatfield Marine Science Center Aquarium during September 19-October 3,2001 were examined for parasites attached to the gills. The species of Sebastes melanops were Microcotyle sebastis baled on the number of clamps and testes. The prevalence of 42.9％ was recorded for host and fourteen worms of three black rockfish were recovered. Mean intensity of infection of Microcotyle sebastis individuals per infected host for black rockfish was 2.0(range 1-11). Monogenea helminth sites were mainly consist of second and third gill arch's filaments of black rockfish. The results revealed that surface area of the 2nd and 3rd pair of gills might affect the distribution of Microcotyle sebastis.

• Korean Journal of Veterinary Service
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• v.24 no.2
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• pp.133-138
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• 2001

Cryposporidium species have a wide host range. These coccidian parasites are found in close association with epithelial cells of many species of animals including mm. The gastrointestinal tract is most commonly affected in young ruminants and this parasite is thought to be considerable importance in calf diarrhea complex. Major outbreaks of cryptosporidiosis have been reported in calves, lambs, pigs and others including avian species. Cryptosporidiosis is transmitted by oocysts of Cryptosporidium species. Because cryptosporidiosis is common infection among animals, early literature considered it a zoonosis. Human infections contracted from calves, cats, and horse feces. However, the resrvoir host is longer considered the major source of infection. Mild cases of disease have been reported in farm workers. Immunosuppressed, very young and very old persons should avoid contact with this parasite because it may cause severe diarrhea. In order to detect of Crytosporidium sp infection from feces of cattle and pigs at Chonbuk Iksan and Kunsan area, sedimentation and modified acid fast stain were applied. The positive rate of Cryptosporidium sp infection from 1, 176 of cattle and 267 of pigs were 0.5 % and 16.8%, respectively. According to area in Iksan and Kunsan, the positive rates were 0.4% and 0.9% from cattle, and 18.9% and 12.1% from pigs, respectively. In cattle, positive detection rate was 0.6% in milking cows but not in Korean cattle.

• The Journal of the Korean Society for Microbiology
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• v.22 no.1
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• pp.61-70
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• 1987

Authors have isolated phages of V. parahaemolyticus from shellfish and investigated some of their characteristics. The results obtained were as follows: Twenty-three phage strains(9.2%) out of 250 specimens were isolated. Plaques of phages were small, clear or turbid and $0.5{\sim}1.5mm$ in diameter. The electron micrographs of K3 phages showed two morphology; one was a hexagonal head about 105nm with a tail about 12nm, the other was a hexagonnal head about 60nm with a tail about 25nm. The host ranges of pahges were limited to V. parahaemolyticus strains and there appeared to be no relationship between the K serotypes of V. parahaemolyticus strains and the host ranges of the phage isolates. The adsorption rate of phages were more than 80% for $10{\sim}15$ minutes, the inactivation rate at $60^{\circ}C$ was more than 99% for $40{\sim}45$ minutes. The pH stability range was between 6.0 and 8.0. The inactivation rate of phages by UV irradiation was more than 99% for $45{\sim}75$ seconds.