• Journal of Korean Ophthalmic Optics Society
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• v.21 no.3
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• pp.215-225
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• 2016

Purpose: The aim of this study was to figure out how the characteristics of soft contact lens materials and pigmentation affect the adherence of C. albicans on soft contact lenses pre-deposited with tear constituents. Methods: The adherent number of C. albicans on clear soft contact lenses (hereinafter clear lenses) and circle soft contact lenses (hereinafter circle lenses) made of etafilcon A, hilaiflcon B and nelfilcon A, respectively, was measured before and after the deposition of artificial tear. Also, bacteria adherence on lenses were observed by a scanning electron microscope. Results: Adherence of C. albicans was significantly different according to lens materials. The amount of adsorption was not different between clear lenses and circle lenses made of etafilcon A however, the number of bacteria absorption was bigger in hilafilcon B and nelfilcon A lenses. More absorption of C. albicans was found in the non-pigmented central area compared the pigmented area, and non-pigmented peripheral area has more bacterial absorption than non-pigmented central area. The number of C. albicans decreased in the case that tear protein was pre-deposited. The maintenance of antibacterial activity against C. albicans was different according to lens materials thus, etafilcon A has the longest period of its maintenance. Conclusions: It was revealed that the number of C. albicans was different according to the characteristics of lens materials, pigmentation or non-pigmentation, the pigmented area of soft contact lenses. Thus, it is suggested that the management method should be different according to the adsorption characteristics of C. albicans.

• Korean Journal of Soil Science and Fertilizer
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• v.30 no.1
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• pp.94-98
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• 1997

This experiment was conducted to investigate the distribution of the soil microflora of Daekwanryung highlands of Kwangwon Province. It was found that soil microorganisms each as Bacteria, Actinomycetes, Fungi, Pseudomonas spp. and Erwnia sp. were mostly in the top 0-15 cm profile. It also was found that soil microflora population was affected in many ways by kind of cropping plant. The number of Erwinia sp. that is one of the soil born plant pathogenic bacteria was more abundant in potato field than chinese cabbage soil. It was also studied difference of mountain and grassland soils from cropping soils.

• Pediatric Infection and Vaccine
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• v.18 no.2
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• pp.201-206
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• 2011

Purpose : Bacteremia is one of the most common causes of morbidity and mortality in children with cancer. The aim of this study was to evaluate the clinical features of bacteremia in pediatric cancer patients. Methods : We retrospectively analyzed bacteremia episodes occurred in pediatric cancer patients at Samsung Medical Center from January 2008 to December 2010. We excluded bacteremia episodes after hematopoietic stem cell transplantation. Results : A total of 141 blood cultures were positive in 121 patients. Thirteen cultures due to contamination were excluded. For analysis, 128 bacteremia episodes in 108 children were included. Gram-positive organisms accounted for 46.9% (60/ 128) and gram-negative organisms for 53.1% (68/128). The source of bacteremia was identified in 21.1% of episodes. Bacteremia due to catheter related infection was observed in 9.4% of episodes (12/128 episodes) and gram-positive organisms were isolated in 75% of episodes (9/12). There were 10 cases (7.8%) of bacteremia associated with septic shock and gramnegative organisms were isolated in 80% of episodes (8/10). Relapses were documented within 30 days in 2 patients who cleared bacteremia which was confirmed after negative blood cultures. Mortality associated with bacteremia was not observed. Conclusion : Continuous monitoring is needed to maintain the tailored strategies to manage pediatric cancer patients with neutropenic fever who are at high risk of developing bacteremia in each institution.

• The Korean Journal of Mycology
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• v.39 no.1
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• pp.7-10
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• 2011

Orchid mycorrhizal fungi (OMF) were examined in roots of the six terrestrial species of orchids collected in Ulleung Islands. Seven OMF isolates from the roots of orchids were identified based on morphological and molecular characters. Internal transcribed spacer region of OMF DNA was amplified using basidiomycete-specific ITS primers, ITS1-OF and ITS4-OF. OMF beloning to Tulasnellaceae and Ceratobasidaceae was identified through molecular analysis.

• Microbiology and Biotechnology Letters
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• v.8 no.2
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• pp.87-92
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• 1980

These experiments were conducted to manage more safe the selected strains and improve their characteristics. The results obtained were as follows: Preservation on soil at the range of 0 to 5 C was suitable and there were no remarkable changes on their abilities to produce citric acid until 10 months preservation. The successive transfer of spore slightly stimulated the selected strain, M-315 to produce citric acid and the spore precultured on sporulation medium for 7-10 days was desirable as inoculum. Under UV-irradiation from the selected strains, 109 mutants whose morphological characteristics were changed were isolated. Among them, the mutant M-80-12 was shown 3.2％ increase on acid producing ability than that of its parent.

• The Korean Journal of Mycology
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• v.27 no.3 s.90
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• pp.234-236
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• 1999

Sphaerotheca fuliginea has previously been recorded as a powdery mildew fungus on dahlia (Dahlia pinnata) in Korea. Six collections of the dahlia mildew by the authors since 1993, however, show that the fungus does not contain conspicuous fibrosin bodies and has sinuate edge lines on conidiophores. These characters clearly indicate that the fungus causing the powdery mildew on dahlia in Korea is Erysiphe cichoracearum. On the other hand, one plant of dahlia grown in a pot was found to be infected with S. fusca (= S. fuliginea s. lat.). It is supposed to be unusual. Therefore, two species of dahlia mildew fungi are distributed and E. cichoracearum is the main cause of dahlia mildew in Korea.

• Proceedings of the Korean Vacuum Society Conference
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• 2012.02a
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• pp.493-493
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• 2012

평행평판 축전 결합 플라즈마는 증착이나 식각 등 많은 공정장비에서 사용된다. 이때 구동주파수를 높여주거나 리액터의 크기를 증가시킬 경우, 플라즈마 밀도가 불균일해진다. 플라즈마 밀도는 플라즈마 내 전기장 분포의 균일도와 관련이 있는 것으로 전기장 분포를 균일하게 만드는 것은 매우 중요하다. 이전 연구에서는 충돌 주파수(공정 압력)가 전기장의 분포에 미치는 영향에 대해 발표하였다 [1]. 본 연구에서는 구동 주파수, 충돌 주파수(공정 압력), 플라즈마 주파수(플라즈마 밀도)가 전기장 분포에 미치는 영향을 알아보았고, 이들의 상관관계를 분석하였다. 플라즈마 주파수(플라즈마 밀도)와 충돌 주파수(공정 압력)는 전기장 분포의 균일도에 영향을 주는 변수이지만 이 둘은 반대 영향을 미쳤다. 따라서 두 주파수가 전기장 분포에 미치는 영향이 균형을 이룰 때 균일한 전기장 분포를 얻을 수 있었다. 이 때 구동 주파수가 증가할수록 균일하게 하는 두 주파수의 영역이 줄어들어 높은 구동 주파수에서는 전기장 분포를 균일하게 하기 어려웠다. 이러한 관계를 이용하여 일정한 구동 주파수와 플라즈마 주파수에서 전기장 분포의 균일도를 10% 이내로 하기 위해 충돌 주파수를 결정할 수 있는 방정식을 구하고, 충돌 주파수와 플라즈마 주파수, 그리고 구동 주파수가 전기장 분포를 균일하게 하는 이들의 관계를 살펴 보았다.

• Journal of Food Hygiene and Safety
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• v.18 no.3
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• pp.113-117
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• 2003

In order to develop a antimicrobial agent, bamboo oil was extracted by high temperature suction from dired bamboo truk and then antimictobial activities against Trichophyton and Pityrosporum are investigated. 1. Bamboo oil showed the strongest antimicrobial effect on Trichophyton mentagrophytes > Epidermophyton floccusum > Trichophyton rubrun. Bamboo oil showed the strongest antimicrobial activity on Trichophyton mentagrophytes. 2. Bamboo oil showed the strongest antimicrobial effect on Pityroporum ovale 75 > Pityrosporum ovale 77. Bamboo oil showe the strongest antimicrobial activity on Pityroporum ovale 75.3 Antimicrobial effect in 50%-ethanol extracts of bamboo oil are similar to 100%-bamboo oil.

• Proceedings of the Korean Vacuum Society Conference
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• 2013.02a
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• pp.493-493
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• 2013

에싱(Ashing)공정을 위한 원격 유도 결합 플라즈마(remote ICP)에서 플라즈마 균일도를 향상하는 연구를 진행하였다. 본 연구에서는 고균일도 플라즈마 발생을 위해 단면적이 다른 2개의 반응 용기를 각각 상부와 하부에 설치하여 각각의 반응 용기 외곽에 방전 코일이 위치하도록 구성하였다. 0.7~1 Torr 공정 압력 범위의 질소와 산소 혼합 기체에서 2,500 W 전력을 인가하였고, 임피던스 정합회로로부터 각각 병렬로 연결된 방전 코일에 전력이 분배되어 인가된다. 에싱 공정을 위한 플라즈마 균일도를 분석하기 위해 Wafer의 위치에서 부유 탐침법을 적용하여 중심부에서 외곽부로 지름축 위치를 변화시키며 플라즈마 밀도와 전자온도를 측정하고, 공정 조건에 따른 에싱율(Asing Rate)을 측정하였다. 동일한공정 조건에서 하나의 방전 코일을 이용한 경우의 플라즈마 균일도 대비 이중 코일 구조를 이용한 경우 플라즈마 균일도가 크게 향상됨을 보였다. 이는 상부의 유도코일이 wafer 위치에서 주로 지름방향 중심부의 플라즈마 밀도에 기여하고, 하부의 유도코일은 주로 외곽의 플라즈마 밀도에 기여해서 나타나는 현상이다. 공정용 장비에서 플라즈마 균일도의 개선으로 공정 수율을 증가 시키는 효과를 기대할 수 있다.

• Proceedings of the Korean Vacuum Society Conference
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• 2013.02a
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• pp.492-492
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• 2013

반도체 공정을 위한 원격 유도 결합 플라즈마(remote ICP)에서 플라즈마 균일도를 향상하는 연구를 진행하였다. 본 연구에서는고 균일도 플라즈마 발생을 위해 단면적이 다른 2개의 반응 용기를 상부와 하부에 설치하였으며, 각각의 반응 용기 외곽에 방전 코일이 위치하도록 구성하였다. 상부의 반응 용기는 외곽에 유도 코일을 권선하였고, 하부의 반응 용기는 고밀도의 플라즈마 생성을 위해 강자성체를 이용하여 권선하였으며, 강자성체는 쿼츠관을 둘러 싼 구조로 되어 있다. 0.5-1 Torr 공정 압력 범위의 아르곤 기체에서 전체 2500 W의 전력을 인가하였고, 임피던스 정합회로로부터 각각 병렬로 연결된 방전 코일에 전력이 분배되어 인가되는 구조로 설계하였다. 반도체 공정을 위한 플라즈마 균일도를 분석하기 위해 wafer의 위치에서 부유 탐침법을 적용하여 wafer 중심부로부터 반경 방향으로 위치를 변화시키며 플라즈마 밀도와 전자온도를 측정하였다. 동일한 공정 조건에서 하부에 강자성체를 사용하여 권선한 이중 구조의 경우 하나의 방전 코일을 이용한 구조 대비 플라즈마 밀도가 증가하였고, 플라즈마 균일도가 크게 향상됨을 보였다. 강자성체를 이용한 하부 코일에 의해 wafer 외곽 부분의 밀도가 높은 분포를 갖는 플라즈마가 형성되고, 상부의 유도코일에 의해 wafer 중심부에 밀도가 높은 플라즈마가 형성되어 wafer의 플라즈마 균일도가 개선된다. 또한, 강자성체를 이용한 하부 코일에 의해 고밀도의 플라즈마가 형성되므로 반도체 공정을 위한 장비에서 플라즈마 균일도의 개선과 밀도의 향상으로 대면적 Dry Strip 공정 (450mm)에 적용 가능하다.