• 한국식품과학회지
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• 제46권3호
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• pp.323-327
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• 2014

새싹채소로부터 분리된 E. faecium의 temperate phage 특성을 mitomycin C를 이용하여 E. faecium으로부터 D-19 phage와 F6 phage를 각각 분리하였다. 분리된 temperate phage는 형태학적 특성을 확인한 결과 모두 Siphoviridae에 속하는 것으로 나타났다. 그리고, 숙주 저해 범위는 55개의 숙주중에서 D-19 phage는 5주, F6 phage는 3주의 E. faecium만을 용균시킬 수 있는 것으로 확인하였다. 다양한 ethanol 농도에서의 안정성은 고농도에서도 매우 안정한 것으로 확인되었으며, pH의 안정성도 pH 4까지 안정한 것으로 나타났다. 본 연구를 통해 아직 연구가 많이 이루어지지 않은 E. faecium의 temperate phage는 host spectrum이 넓지 않은 것으로 나타났고 pH, 온도 등의 환경인자에 상당히 강한 안정성을 가지고 있는 것으로 나타났다.

• 한국균학회지
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• 제49권4호
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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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• 제38권3호
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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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• 제23권3호
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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.

• 한국멀티미디어학회논문지
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• 제8권4호
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• pp.544-553
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• 2005

본 논문에서는 사회적 상호작용을 극대화 하고, 중도 탈락률을 낮추며, 학습자의 고립감을 해소하기 위해 바람직한 온라인 학습공동체 형성을 위해 취향검사 항목을 개발 하였으며, 개발한 취향검사 항목을 동질성과 이질성으로 구분하여 항목을 개발하고, 이를 바탕으로 온라인상에서 지능적 에이전트 기법에 의한 학습공동체를 자동으로 그룹핑하는 e-learning 시스템(IIGS)을 개발하였다. 실제 1,000명을 대상으로 실험한 결과, 151개 그룹이 자동으로 생성되었으며 이중 34% 정도가 매우 높은 학습만족을 보여 그룹을 계속적으로 유지하고자 하였다.

• 대한약학회:학술대회논문집
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• 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.1
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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)

• 대한수의학회지
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• 제30권3호
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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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• 제16권4호
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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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• 제32권spc8호
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• pp.3175-3178
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• 2011

• Steel and Composite Structures
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• 제5권2_3호
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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.