• Journal of the Korea Organic Resources Recycling Association
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• v.4 no.1
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• pp.13-21
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• 1996

For treating tannery wastewater containing high sulfate and heavy metals, test was performed to assess their performance, competition between SRB (sulfate reducing bacteria) and MPB (methane producing bacteria), and the activity of MPB according to change of chromium concentrations. COD removal efficiency was above 70% at VLR (volumetric loading rate) of 2.0 gCOD/I.day and HRT (hydraulic retention time) of 18hrs at $35^{\circ}C$. In the competition between SRB and MPB, about 15% of the removed COD was utilized by SRB in the begining, but it became 43% at the end. It indicated that MPB was strongly suppressed by the occurrence of significant sulfate reduction since a large electron flow was uptaken by SRB. For the entire experiment, removal efficiencies of chromium concentration were more than 90%. Despite high removal efficiencies of chromium concentration, performance of reactor did not change significantly during the experimental periods. Expecially, chromium (III) is tannery wastewater is less toxic than chromium (VI).

• Journal of Veterinary Clinics
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• v.13 no.2
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• pp.130-139
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• 1996

Malassezia pachydercatis균은 개 외이염의 주된 원인균으로 알려져 있으나, 그 감염률은 지역에 따라 많은 차이가 있다. 그러나 그 기병론적인 역할에 대해서는 아직 명확히 밝혀지지 않았다. 이에 본문에서는 국내에서 사육되는 개의 외이염에서 Malassezia pachydercatis 균의 분리율을 조사하고, Malassezia pachydercatis에 대한 혈중 항체와 외이염과의 연관성을 밝혀 Malassezia pachydercatis에 의한 외이염 진단을 위한 도구로서 간접 ELISA 법의 유용성을 평가해 보고자 본 연구를 수행하였다. 총 112두 중, 외이염에 감염된 개 44두와 정상견 68두를 대상으로, 심부외이도에서 취한 가검물을 배양검사하였고, Malassezia pachydercatis 항원에 대한 혈청내 IgG와 IgM 역가를 간접 ELISA법에 의해 측정하였다. 살아있는 Malassezia pachydercatis 균을 3두의 정상견 외이도에 접종하여 Malassezia pachydercatis 균의 실험적 감염에 대한 조직병리학적 소견, 조직내 침투 정도, 그리고 접종 후 시간경과에 따른 IgG와 IgM의 혈중 역가변화를 측정하였다. Malassezia pachydercatis 균은 외이염이 있는 개 귀에서 가장 높게 분리(50.0%)되었고, 정상귀에서는 낮게 분리(6.3%)되었다. Malassezia pachydercatis 항원을 이용한 간접 ELISA 법 진단에서, Malassezia pachydercatis 양성배양인 외이염 개체에서 IgG와 IgM에 대한 민감도는 각각 41.7%, 20.8%이었고 특이도는 88.2%, 85.2% 이었다. 실험적으로 Malassezia pachydercatis 를 접종한 3두중 1두에서만 조직병리학적 변화와 모낭에 Malassezia pachydercatis 균체가 확인되었으며, IgG와 IgM 혈중역가도 유의성 있게 증가하였다. 국내에서 사육되는 개 외이염의 주된 원인균은 Malassezia pachydercatis 균이었고 이 균의 혈중항체는 유의성 있게 증가하였으며(p<0.005), 간접 ELISA법은 Malassezia pachydercatis 에 의한 개외이염의 유용한 진단도구임을 증명하였다.

• Korean Journal of Food Science and Technology
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• v.17 no.1
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• pp.51-53
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• 1985

Soy milks prepared from full-fat soy flour, defatted soy flow, soy protein concentrate (SPC) and soy protein isolate (SPI) were fermented with Lactobacillus acidophilus. Effects of lactic fermentation on the flavor and volatile compounds of soy milks were investigated. Sensory evaluation showed that the flavor of soy yogurt beverages was inferior to that of milk yogurt beverage and the flavor of SPI-yogurt beverage was better than that of other soy yogurt beverages. SPI-milk fermented with L. acidophilus was more acceptable than unfermented SPI-milk. Lactic fermentation reduced n-hexanal in SPC-milk and SPI-milk while it increased diacetyl in both soy milks.

• The Korean Journal of Mycology
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• v.21 no.3
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• pp.172-187
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• 1993

Forty eight fungal isolates were isolated from the maeius collected through the whole nation. Out of them, nine isolate were observed to be zygomyceteous fungi(4 genera and 9 species): Mucor hiemalis, M. circinelloides f. griseo-cyanus, M. circinelloides, M. jansseni, M. racemosus f. racemosus, Mortierella isabellina, Rhizopus stolonifer, R. oryzae, and Absidia corymbifera. Four species(M. circinelloides f. griseo-cyanus, M. hiemalis, M. jansseni, and R. oryzae) identified here were known as species involved in maeiu but not described in detail. The others were first reported as a species inhabiting in the maeiu. Two species of M. hiemalis f. hiemalis. and M. circinelloides f. griseo-cyanus were determined to play a role in biochemical changes of soybean in the fermentation of maeiu. However, the others seldom inhabited but considered to be comtaminated fungi in maeiu.

• Journal of Dental Rehabilitation and Applied Science
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• v.30 no.3
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• pp.199-205
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• 2014

Purpose: The purpose of this study was to evaluate the transmission of candida in denture by dental polishing lathe. Materials and Methods: Maxillary complete dentures made from the same model were infected with Candida albicans. The infected dentures were polished by dental polishing lathe with sterile pumice and distilled water. And then sterile maxillary complete dentures were polished with same method. Polishing surface was wiped with a cotton swab and the sample was checked for Candida albicans. The polishing wheel at room temperature was checked for Candida albicans every 24 hours for 3 days. Results: A considerable number of Candida was found on the polished sterile dentures. And the Candida albicans in polishing wheel was detected at up to two days. Conclusion: An anti-infection measure is urgently needed when dental polishing lathe is used for denture polishing, because of the possibility of fungal infection.

• Journal of the Korean Society of Radiology
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• v.14 no.5
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• pp.537-543
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• 2020

The elderly population in the modern society is growing rapidly due to advance medical technology and minimally invasive surgery. Therefore, as the tendency to use medical device is increasing, pathogenic infection is a concern. Therefore, the first aim of modern medicine is infection prevention in medical place. Recently, patient implants are increasing using 3D printing. Hydroxyapatite is used as a representative material. And, there haven't had currently absorbed dose standard for sterilization of hydroxyapatite discs. Escherichia coli and Streptococcus mutans contaminated on the surface of hydroxyapatite discs were irradiated at each absorbed dose of 0, 0.5, 1.0, 3.0, 5.0 kGy using Gamma-ray of cobalt and Electron-beam of linear accelerator. Then, the number of bacteria was measured in the sample by the decimal dilution method. After sterilization, a non-parametric testing method was performed to compare the survival of Escherichia coli and Streptococcus mutans. As a result, Escherichia coli was sterilized at 1 kGy or more and Streptococcus mutans at 3 kGy or more on absorbed dose. It is considered possible to perform sterilization at a lower value than the recommended absorbed dose of radiation sterilization.

• Proceedings of the Korean Vacuum Society Conference
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• 2011.02a
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• pp.280-280
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• 2011

유도결합 플라즈마를 이용한 식각 장치에서 플라즈마 균일도 향상에 대한 수많은 연구가 이뤄지고 있다. 안테나의 디자인, 인가 전력과 주파수, 안테나와 기판간의 거리, 기판과 챔버 외벽간의 거리 등 다양한 변수들이 변화되어 왔다. 또한, 최근에는 식각 균일도뿐만 아니라 식각 속도 향상에도 많은 관심이 모아지면서 유동에 영향을 주는 GDP 구조가 다시 중요해지고 있다. 본 연구에서는 300 mm 식각장치를 형상화하고, GDP의 구조와 유량비에 따라 플라즈마의 균일도에 어떻게 영향을 끼지는지 사용 유체역학 전산모사 프로그램인 CFD-ACE+를 이용하여 예측해 보았다. 안테나는 2중 직렬방식으로 안쪽과 바깥쪽의 안테나에 각기 다른 전력을 인가 할 수 있는 구조를 사용했으며, 압력은 10에서 60 mTorr까지 변화시켰다. GDP의 구조는 안쪽 입구와 바깥쪽 입구가 있으며 역시 따로 유량을 조절할 수 있도록 설계하였다. 안쪽 입구는 수직방향을 향하고 있으며, 바깥쪽 입구는 90도 이내의 각을 갖도록 꺾여 있는 것과 수평방향으로 주입할 수 있는 구조, 두 가지를 사용하였다. 유량 비율은 안쪽 입구와 바깥쪽 입구를 2:8, 5:5, 8:2로 고정하였다. 우선 GDP의 구조가 90이내의 각을 갖도록 주입되는 구조에서는 어떤 유량비율에서도 약간의 vortex가 발생했다. 수직방향의 유량이 감소될수록 기판에서 멀리서 발생했으며 강도 또한 감소했다. 기판 표면에서의 압력분포 균일도도 8:2에서 2.8%, 2:8에서 0.6%로 향상되었다. 2:8의 유량 비율에서 압력을 10에서 60 mTorr까지 향상시키면 vortex 효과는 감소되나 기판에서의 압력 균일도가 0.8%까지 약간 나빠졌다. 여기서 발생되는 vortex는 GDP 구조를 수평방향으로 주입되기 함으로서 해결할 수 있었으며, 압력 균일도도 0.2%까지 향상시킬 수 있었다. 또한, 강한 수직방향의 유량은 중심에 발생하는 플라즈마의 중앙을 밀어내는 효과를 확인했으며, 실험적 증명이 추후 연구단계로 진행될 예정이다. 식각 균일도나 식각 속도를 예측하려면 CF계열의 복잡한 가스를 사용해야하기 때문에 유량이 플라즈마에 미치는 영향을 보기 위해서 본 연구에서는 단일종인 Ar 가스만을 사용하였다. 첫 단계로 이와 같이 최적화시킨 유동조건에서 복잡한 식각가스를 이용한 플라즈마 계산은 다음 단계로 준비 중에 있다.

• Korean Journal of Microbiology
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• v.37 no.1
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• pp.49-55
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• 2001

Bacillus anthracis is a gram-positive spore-forming bacterium that causes the disease anthrax. The anthrax toxin contains three components, including the protective antigen (PA), which binds to eucaryotic cell surface receptors and mediates the transport of toxins into the cell. In this study, the entire 2,294-nucleotide protective antigen gene (pag) was sequenced from 4 of B. anthracis strains to identify potential variation in the toxin and to further our understanding of B. anthracis evolution in Korea. Sequence alignment of the entire PA gene from 30 strains representative of the four B. anthracis diversity groups revealed mutations. The mutation of B. anthracis BAK are located adjacent to a highly antigenic region crossing the junction between PA domains 3 and 4 shown to be critical to LF binding. The different mutational combinations observed in this study give rise to 11 PA genotypes and 4PA phenotypes. Three-dimensional analysis of all the amino acid changes (Ala to Val) observed in BAK indicated that these changes are not only close sequentially but also very close in three-dimensional space to the antigenic region importan tfor LF binding. Phylogenetic (cladistic) analysis of the pag corresponded with previous strain grouping based on chromosomal variation, suggesting that plasmid evolution in B. anthracis has occurred with little or no horizontal transfer between the different strains.

• Journal of the Korean Vacuum Society
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• v.19 no.3
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• pp.190-198
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• 2010

Asymmetric model for plasma uniformity by Ar and $CF_4$ was modeled by the antenna structure, the diameter of chamber, and the distance between source and substrate for the development of plasma equipment for 450 mm wafer. The aspect ratio of chamber was divided by diameter, distance from substrate, and pumping port area. And we found the condition with the optimized plasma uniformity by changing the antenna structure. The drift diffusion and quasi-neutrality for simplification were used, and the ion energy function was activated for the surface recombination and etching reaction. The uniformity of plasma density on substrate surface was improved by being far of the distance between substrate wall and chamber wall, and substrate and plasma source. And when the antenna of only 2 turns was used, the plasma uniformity can improve from 20~30% to 4.7%.

• The Korean Journal of Mycology
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• v.22 no.3
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• pp.229-246
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• 1994

Powdery mildew fungi from 246 different species of host plants were collected at Kangwon province during 1989-1993 years. They were identified and classified into 13 genera and 83 species by examining various morphological characteristics of taxonomic value. Most of host plants were infected with one species of powdery mildew fungus, but eight plant species with two or three different mildews. Among 246 host plants collected, 43 species were added as the new host plants of powdery mildew fungi in Korea. Two Oidium spp. from Hibiscus and several Compositae plants were described to suggest their taxonomic problems.