• Korean Journal of Food Science and Technology
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• v.46 no.3
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• pp.323-327
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• 2014

To analyze the characteristics of bacteriophages in Enterococcus faecium, D-19 and F6 phages were induced from five E. faecium isolated from sprouts by the treatment with mitomycin C. The bacteriophages of D-19 and F-6 had long, non-contractile tails and icosahedral heads, and were members of Siphoviridae family. As the host spectrum, D-19 phage lysed five out of 55 strains of E. faecium, whereas F6 phage lysed only three strains. Both D-19 and F6 phages displayed similar and high stabilities against ethanol and pH capable of resisting the exposure to 100% ethanol and pH 4.

• The Korean Journal of Mycology
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• v.49 no.4
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• pp.545-553
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• 2021

In 2021, seven yeast strains were isolated from earthworm (Eisenia andrei) gut samples collected from the Nanji Water Regeneration Center in Goyang City, Gyeonggi Province, Korea. A total of seven yeasts were isolated, of which three strains have not been previously reported in Korea. To identify the yeasts, pairwise sequence comparisons of large subunit (LSU) rDNA sequences were performed using the basic local alignment search tool (BLAST). Assimilation test and cell morphology analysis were performed using the API 20C AUX kit and phase contrast microscope, respectively. Five of the seven strains were assigned to the genus Candida of the order Saccharomycetales of the class Saccharomycetes, and two to the genus Apiotrichum of the order Trichosporonales of the class Tremellomycetes. The yeast strain Candida sojae E2 belongs to the family Debaryomycetaceae, and Apiotrichum laibachii E8 and A. laibachii E9 belong to the family Trichosporonaceae. All strains were cultured in yeast mold agar for three days and showed different colony forms. C. sojae E2 was round and entire shaped, while A. laibachii E8 and A. laibachii E9 was round and convex shaped. This study focuses on the description of the three yeast strains that have not been officially reported in Korea.

• The Plant Pathology Journal
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• v.38 no.3
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• pp.248-253
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• 2022

Erwinia amylovora is a devastating bacterial plant pathogen that infects Rosaceae including apple and pear and causes fire blight. Bacteriophages have been considered as a biological control agent for preventing bacterial infections of plants. In this study, nine bacteriophages (ΦFifi011, ΦFifi044, ΦFifi051, ΦFifi067, ΦFifi106, ΦFifi287, ΦFifi318, ΦFifi450, and ΦFifi451) were isolated from soil and water samples in seven orchards with fire blight in Korea. The genetic diversity of bacteriophage isolates was confirmed through restriction fragment length polymorphism pattern analysis. Host range of the nine phages was tested against 45 E. amylovora strains and 14 E. pyrifoliae strains and nine other bacterial strains. Among the nine phages, ΦFifi044 and ΦFifi451 infected and lysed E. amylovora only. And the remaining seven phages infected both E. amylovora and E. pyrifoliae. The results suggest that the isolated phages were different from each other and effective to control E. amylovora, providing a basis to develop biological agents and utilizing phage cocktails.

• KSBB Journal
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• v.23 no.3
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• pp.187-192
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• 2008

Lysozyme-producing microorganisms were isolated to obtain bacteria which can efficiently solubilize microbial cells. Cells of normal and chloroform-treated Escherichia coli and Micrococcus Iysodeikticus were used as model substrates to isolate lysozyme-producing microorganisms and investigate the efficiency of cell lysis. The culture supernatant of the isolate New1 (98% similarity of 16S rDNA sequence with Thermomonas haemolytica) showed different lytic characteristics for different substrates. Thermal treatment (autoclave) of substrate cells showed a significant effect on cell solubilization by culture supernatant of the New1. For autoclaved substrate cells, E. coli, M. Iysodeikticus and chloroform-treated E. coli were solubilized by 58.7%, 49.4% and 79.1%, respectively, in the culture supernatant of New1. The lytic activity of New1 was mainly caused by lysozyme produced by the isolate. It was also showed that New1 exhibited high protease activity and a little cellulase activity.

• Journal of Korea Multimedia Society
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• v.8 no.4
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• pp.544-553
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• 2005

In this paper, the research has been done to develop the inclination test items to form the desirable online learning community in which social interaction may be maximized, dropout rate lowered and learners' feeling of isolation eliminated. Once developed, the inclination test items have been classified into homogeneous ones and heterogeneous ones. And on the basis of the results of this research, Intelligent agent based Inclination Test Grouping e-learning System(IIGS) has been developed, which can perform automatic grouping of online leaning community by intelligent agent. The results of this research with 1,000 teachers in reality by means of developing the grouping system have shown that 151 groups are automatically formed. Among them, 34% have shown very high degree of learning satisfaction and intended to maintain the groups in the future.

• Proceedings of the PSK Conference
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• 2003.04a
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• pp.259.3-260
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• 2003

Alzheimer's disease(AD) is the most common cause of senile dementia in elderly people and the causes of AD are currently not fully understood. However, AD is generally understood to be associated with reduced levels of acetylcholine in the brain as cholinergic neurons are lost and cholinergic neurotransmission declines. There are growing evidences that two types of cholinesterase(ChE), i.e., acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) both play important roles in the regulation of acetylcholine level in brain and thus may have a crucial role in the development and progression of AD. (omitted)

• Korean Journal of Veterinary Research
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• v.30 no.3
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• pp.287-295
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• 1990

The purpose of this study was the examination for presence of pilus antigen, O serogroups, colicin production, antibiotic susceptibility and plasmid profiles among E coli isolated from diarrheal piglets and fattening pigs in Taegu province. Of 145 E coli isolated, 98 strains (67.4%) possesed pilus antigens which belonged to either K88 (47.6%), K99 (11.7%) or 987P (8.3%) types. Fifty-nine strains (40.7%) were classified into tenO serogroups and their types were O8 (22.0%), O20(16.9%), O141(15.3%), O9(10.2%), O45(10.2%), O139(8.5%), O064(6.8%), O149(5.0%), O157(3.4%), and O115(1.7%). Thirty-three strains (22.8%) were colicinogenic and 6 strains (4.1%) were hemolytic. One hundred and thirty-nine strains (95.9%) of 145 E coli isolates were resistant to ampicillin, chloramphenicol, gentamicin, kanamycin, streptomycin, tetracycline, rifampicin and nalidixic acid, alone or in combination thereof. Ninety strains (64.7%) of 139 drug resistant strains carried R factor (R) which were transferable to the recipient by conjugation. In gel electrophoresis for the isolation of plasmid DNA, the number of plasmid DNA band varied from 2 to 11 in 16 E coli with pilus antigen. It's molecular weight ranged from 1.0 to 60.0 megadalton.

• Journal of Microbiology and Biotechnology
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• v.16 no.4
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• pp.538-542
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• 2006

Three new compounds were isolated from the methanol extracts of buckwheat (Fagopyrum esculentum) hull, and their structures were determined to be 6,7-dihydroxy-3,7-dimethyl-octa-2(Z),4(E)-dienoic acid (1), 6,7-dihydroxy-3,7-dimethyl-octa-2(E),4(E)-dienoic acid (2), and 4,7-dihydroxy-3,7-dimethyl-octa-2(E),5(E)-dienoic acid (3) by NMR and MS spectroscopic analyses. These compounds at $500{\mu}g$ concentration showed antimicrobial activity against Staphylococcus aureus, demonstrated by the paper disc method.

• Bulletin of the Korean Chemical Society
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• v.32 no.spc8
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• pp.3175-3178
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• 2011

• Steel and Composite Structures
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• v.5 no.2_3
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• pp.169-180
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• 2005

Current codes of practice do not exist in isolation, and rules that have been developed assume certain material properties and minimum workmanship in fabrication and erection. These are either in separate documents or different parts of the code. This paper explains the main requirements for materials and workmanship and how they can be related to design and construction in general. The use of very high strength steels is also considered and the measures that may be needed to allow their use with modern codes are also presented.