형질 전환된 Saccharomyces cerevisiae의 leucocin A항균 활성도에 대한 탄소원의 영향

이성일,박진용,정종근,이동근,이상현,하종명,하배진,이재화,Lee Sung-ll,Park Jin-Yong,Jung Jong-Ceun,Lee Dong-Ceun,Lee Sang-Hyeon,Ha long-Myung,Ha Bae-Jin,Lee Jae-Hwa 한국생명과학회 2005 생명과학회지 Vol.15 No.6

B. subtilis에 대한 항균 활성을 파악하기 위하여 bacteriocin의 일종인 leucocin A로 형질전환된 효모를 배양 시간별로 채취하여 광학밀도, 총 분비 단백질량, 단백질 분해효소 그리고 향균활성을 측정했다. Sucrose > glycerol > glucose > fructose 순으로 세포 증식이 높게 확인되었고, glyceroldmf 제외한 탄소원에서 총분비 단백질은 배양 15 시간까지 증가되었다. Leucocin A의 향균활성(antibacterial activity)은 성장양상, 총 분비 단백질과 비례 하였으며 배양 15 시간에 glucose와 sucrose에서 배양한 상등액이 B. subtilis 성장을 가각 $65.5\%$, $72.6\%$ 감소하는 것으로 나타났다. 정지기 이후에는 향균활성이 급속히 감소하였는데, 이는 항균활성을 보이는 leucocin A가 단백질이고, 단백질 분해효소가 정지기 이후 증가한 것에 의한 것으로 사료된다. 본 연구는 향후 식품산업뿐만 아니라 항생제 생산 사용되기 위한 산업적 기초 자료로써 이용 될 것이다. The aim of this study was to increase production of leucocin A, a kind of bacteriocin, in a transformed variety of S. cerevisiae. We investigated optical density, total secreted protein, protease activity, and antibacterial activity for the transformed S. cerevisiae in different carbon sources. The production of leucocin A growth-associated, and antibacterial activity, according to carbon source, was in the order of sucrose, glucose, glycerol, and fructose. Antibacterial activity was $10.6\%$ higher in the presence of sucrose than glucose. This is the first report regarding the effect of carbon sources on the production of leucocin A in transformed S. cerevisiae, as far as we ascertain. Our results could prove useful in the industrial production of natural preservatives.

교육시설 화재위험성 평가를 위한 기초조사에 관한 연구

이성일,함은구,Lee, Sung-Il,Ham, Eun-Gu 한국재난정보학회 2021 한국재난정보학회 논문집 Vol.17 No.2

연구목적: 교육시설 화재위험성 평가를 위한 기초 데이터 확보를 위하여 화재하중 분석하였다. 사전조사로 화재하중을 산정하기 위해 학교시설의 화재하중과 관련된 기초자료를 수집하였다. 연구방법: 기초자료는 화재하중의 정의 및 종류, 화재하중 산정을 위한 연소열 데이터 화재하중에 대한 선행연구를 통하여 진행하였고 화재하중 산출시 구획실에 존재하는 가연물 중량에 해당 연소열을 곱하여 산정하였다. 연구결과: A 초등학교의 고정가연물은 교실, 음악실, 교무실은 정서나 안전을 고려하여 바닥이 주로 목재로 이루어져 있었으며, 나머지 구획실은 석재로 이루어졌다. 천장과 벽은 석고보드, 콘크리트로 되어있어 가연물에 속하지 않았다. 각 실별로 대표적인 적재가연물은 교실은 책상, 의자, 사물함 등으로 나타났으며 과학실은 실험기구함, 실험도구함이 주를 이루어었으며 도서실은 책과 서가, 열람기구 등이 큰 비중을 차지하였다. 결론: A 초등학교의 적재가연물에 따른 적재화재하중은 도서실, 컴퓨터실, 영어학습실, 교무실, 일반교실, 과학관, 음악실의 순으로 나타났다. Purpose: Fire load analysis was conducted to secure basic data for evaluating fire risk of educational facilities. In order to calculate the fire load through a preliminary survey, basic data related to the fire load of school facilities were collected. Method: The basic data were the definition and types of fire loads, combustion heat data for the calculation of fire loads. The fire load was evaluated by multiplying the combustion heat by the weight of the combustibles in the compartment when calculating the fire load. Result: As for the fixed combustible materials of A-elementary school, the floor was mainly made of wood, in consideration of emotion and safety in the classroom, music room, and school office, and the rest of the compartments were made of stone. The ceiling and walls were made of gypsum board and concrete, so they were not combustible. The typical inflammable items in each room were desks, chairs, and lockers in the classroom, and the laboratory equipment box and experimental tool box were the main components in the science room, and books, bookshelves, and reading equipment occupied a large proportion in the library room. Conclusion: 'The fire loads of A-elementary' schools according to the combustibles loaded were in the order of library, computer room, English learning room, teacher's office, general classroom, science hall, and music room.

연근해 주요해역내의 해양 폐기물 조사 기법

이성일,Lee, Seong-Il 한국어촌어항협회 2005 어항어장 Vol.73 No.-

진동식 촉각 자극에 대한 손의 절대 민감도 반응

이성일,Lee, Seong-Il 대한인간공학회 1998 大韓人間工學會誌 Vol.17 No.2

The objective of this study is to investigate hwnan operator's perceptual and psychophysical responses to vibrotactile stimulation on various parts of the hand. Using a small vibrotactile display, five different loci of the hand along with two other mechanical parameters consisting vibrotactile stimulations, which are vibration frequency and number of active contactors, were examined for the effects on absolute thresholds. All test variables were found to have significant effects on thresholds. It was observed that absolute threshold is a function of vibration frequency and number of active contactors. Tactile sensitivity was the greatest at the vibration frequency of 240 Hz, and the fingertip was found to be the most sensitive locus on the hand. The area of stimulation on the hand was also found to be significant in that the sensitivity increased with the number of active contactors. The results of the study generally supported those of other previous studies. It should also be noted, however, that the conclusions from the study should be limited to the absolute sensitivity, not to the suprathreshold intensities of normal everyday contact with the hands.

Special Theme_ICT 접근성 향상 - 모바일 접근성 지침의 내용과 의의

이성일,Lee, Seong-Il 한국정보통신기술협회 2011 TTA저널 Vol.137 No.-

신장율 변화에 의한 폴리프로필렌 필름의 정전기 대전 특성

이성일,김상현,Lee, Sung-Ill,Kim, Sang-Hyeon 한국전기전자재료학회 2010 전기전자재료학회논문지 Vol.23 No.1

This paper examined the effects of specimen elongation on the electrostatic electrification voltages when polypropylene film specimens with 500%, 650% and 700% elongations were rotated at 1550 rpm. The results were as follows. The decease of electrification voltage was not measured according to the time elapse, in case of elongated specimens with 70% environment humidity. As +10 kV was applied to the specimens with 650% elongations, the electrostatic electrification voltages were increased by the effect of environment humidity (1.23~1,25 kV at 50~60% humidity, and 1,46 kV at 70% humidity). The voltages were decreased to 1.2 kV at 700% elongation. As -10 kV was applied to the specimens with 500%, 650% and 700% elongations, the electrostatic electrification voltages were negatively increased with the increase of environment humidity and the elongation of specimens.

보강제 변화에 따른 실리콘 고무의 정전기 열화 특성에 관한 연구

이성일,Lee, Sung Ill 한국전기전자재료학회 2015 전기전자재료학회논문지 Vol.28 No.2

In this study, we have come to the following conclusions regarding to the electrification properties (electrostatic electrification voltage and electrification relaxation time) of electrostatics in the three type of specimen (size: $4cm{\times}4cm{\times}0.103cm$) of silicone rubber which is mixed with the ATH (Aluminium Trihydrate(Al($OH_3$)) of 30 phr, 60 phr, 120 phr as reinforcing filler. The electrification properties of electrostatics were measured for the different mixing ratio of ATH with the applied voltage of DC 10 kV at the temperature range of $10^{\circ}C{\sim}30^{\circ}C$ and humidity range of 60%~80%. When the temperature remained constant, the electrical resistance decreased as the humidity increasing in the range of 60%, 70%, 80%. In contrast, when the humidity remained constant, the electrical resistance increased as the temperature increasing in the range of $10^{\circ}C$, $20^{\circ}C$, $30^{\circ}C$. Regarding these results, may be it is because the absorption of O-H molecule appeared in the silicone specimen. It was confirmed that when the temperature remained constant, the electrification relaxation time decreased as the humidity increased. In contrast, when the humidity remained constant, the electrification relaxation time increased as the temperature increased.

보강제 변화에 따른 실리콘 고무의 트래킹 열화 특성에 관한 연구

이성일,Lee, Sung Ill 한국전기전자재료학회 2014 전기전자재료학회논문지 Vol.27 No.12

It found that the maximum temperature of the arc discharge occurred on the Silicone rubber sample significantly decreased with increasing the reinforcing agent. It was confirmed that the current value decreased with increasing the aluminium trihydrate($Al(OH)_3$) and the current value increased with reducing the primary resistance over time. Regarding these results, may be it is because the degradation due to the electro-conductive carbonization was improved and the properties of dielectric breakdown was reduced by the flame retardant reinforcing agent. It found that the electro-conductive carbonized road has not happened by increasing the flame retardant reinforcing agent. Regarding to the arc discharge, this study show that the arc arising near the lower electrode of sample has disappeared.

실리콘 고무 시트의 유전특성에 미치는 주파수 의존성에 관한 연구

이성일,Lee, Sung Ill 한국전기전자재료학회 2020 전기전자재료학회논문지 Vol.33 No.5

In this study, the following results were obtained by analysis of electric properties with FT-IR, DSC, XRD, and SEM, in the range of temperature 30~160℃ and frequency 0.1~200 kHz, when filling agent (0~100 phr) and silicone oil (0~12 phr) were added to raw silicone rubber. In the case of 100 phr mixed samples, the relative dielectric constant εr gradually decreased from 4.3 to 3.96 as frequency increased, and the dielectric loss tan δ decreased to 0.01 at 300 Hz, then increased to 0.022 at 30 kHz, then decreased to 200 kHz. The FT-IR analysis identified the same binding structure according to the chemical composition of added silica (SiO₂). Through DSC analysis, we could determine the change of heat quantity and the glass transition temperature of each specimen. In the XRD analysis, it was found that the images SiO₂, TiO₂, and Fe₂O₃ appeared for specimens with 0%, 50% and 100% filling agent. Finally, the SEM analysis confirmed that particles of 0.5 to 1.5 ㎛ size with silica (SiO₂) mixing were dispersed evenly.

실리콘 고무의 부분방전 특성에 관한 연구

이성일,권영천,Lee, Sung-Ill,Kwon, Young-Cheon 한국전기전자재료학회 2011 전기전자재료학회논문지 Vol.24 No.11

In this thesis, the silicone filler with a sample size of 0~75 phr and void size of 2~4.5 mm is prepared in order to diagnose the defect of void which exists in widely used insulation material, silicone rubber. In this silicone rubber sample, electrodes are connected and whilst the voltage changes, applied voltage 7 kV~9 kV is increased constantly over time and discharge quantity, discharge frequency and applied voltage (T-QNV) were measured. The discharge quantity of the applied voltage (VQ) is measured to estimate inception voltage and extinction voltage. In addition, under the condition of maintaining constant applied voltage, discharge quantity and discharge frequency (QN) are measured, and its characteristics are analyzed.