토양으로부터 分離한 Bacteriophage의 특성

박현균,김도경,박경진,전홍성,박종필,김종승,김성준 조선대학교 부설 유전생물공학연구소 1992 유전생물공학연구지 Vol.2 No.-

환경 미생물 분야와 산업미생물 분야 및 분자생물학 분야에서 주목을 받고 있고, 많은 연구가 된 새로운 E. coli의 bacteriophage를 토양으로 부터 분리해서, 그 물리적인 특성과 핵산을 밝혀내, phage상호간의 관련성을 검토하여 보았다. 그 결과를 요약하면 다음과 같다. 1. 토양으로 부터 분리한 phage는 숙주균에 따라 SJ-1, SJ-2, SJ-3, SJ-4, SJ-5, SJ-6, SJ-7이라 명명하였다. SJ phage들은 높은 숙주특이성을 나타내 phage SJ-2, SJ一7은 단일종 숙주균에만 감염이 되었고, SJ-1, SJ-3, SJ-4, SJ-5, SJ-6은 다중독성을 나타내었다. 2. 7종류의 SJ-phage는 본 실험조건하에서는 모두 virulent phage임이 밝혀졌다. 모든 용균반의 형태는 중앙이 투명한 둥근 모양이었으며 주변에 무리가 있는 것과 없는것 두가지 형태를 나타냈다. 용균반의 크기는 1-5mm이었으며, SJ-5phage의 용균반이 5mm로서 가장 컸고 SJ-7 phage가 가장 적었다. 숙주균은 OD_600 0.3-0.5상태에서 가장 감염되기가 좋았다. 그리고 상층배지의 한천 농도와 양은 0.5%와 3ml이 가장 좋은 조건이었다. 3. 일단 증식 실험의 결과를 보면 SJ-phage는 잠복기가 15-50분이었고 평균 phage방출수는 190-250이었다. SJ-6과 SJ-7이 잠복기가 15분으로 가장 짧았고 SJ-4가 50분으로 가장 길었다. 평균 방출수는 SJ-3과 SJ-5가 250정도로 많았으며 SJ-1과 SJ-2는 약 190정도였다. 4. SJ-phage는 PD buffer에서 안정하였고, magnesium ion 5×10^-3M의 첨가는 phage에게 큰 안정성을 주었다. SJ-phage는 pH6과 pH9사이에서 안정하였으며 그 pH는 숙주균의 최적 pH였다. SJ-phage의 온도 불활성화는 40 ℃이상에서 불활성화되기 시작하여 60 ℃이상에서는 완전히 불활성화 되었다. 자외선 조사에 의한 불활성화에서 SJ-phage는 120초 이후에 완전히 불활성화 되었다. All phages used in this experiment were isolated from soil of the surburbs of Chun-Nam, and they designated as phage SJ-1, SJ-2, SJ-3, SJ-4, SJ-5, SJ-6, SJ-7. The hosts were JM105, JM109, K802, LE392, MC1000, MV1184 and PSM CC, respectively. These phages were virulent under the experimental conditions. They produced plaques with dear and round without halo. The size of plaques was 1-5mm in diameter. SJ-phages were stable in 5×10^-3M Mg^2+. Thermostability experiments indicated that SJ-phages were stable at 37℃. Optimal pH of the phages were 6-9. Exposure of the phages to U.V. for 120 seconds resulted in complete inactivation. In one-step growth experiments, the latent period at 37 ℃ was about 15-50 min and the average burst see was 190-250. Agarose gel electrophoresis of the phage DNA showed single band of high molecular weight from SJ-1 to SJ-7 phages

볼 엔드밀 가공시 채터가 가공면에 미치는 영향

박춘우,홍남표,김병희 江原大學校 産業技術硏究所 2001 産業技術硏究 Vol.21 No.A

This paper deals with the study on the culling characteristics in ball-end milling process. First of all, the effects of the geometric cutting conditions such as the spindle speed, feedrates on the surface integrity and machining stability were evaluated by the analytical and the experimental approaches. A large amount of experimental sets are performed to evaluate the effects of chatter phenomenon on the machined surface. The optical microscope and the surface roughness measuring machine are used to measure the surface integrity and roughness of the machined surfaces

전기자극이 건의 치유에 미치는 영향에 관한 실험연구

홍성철,김덕래,김태연,정전은,박길홍 大韓成形外科學會 1991 Archives of Plastic Surgery Vol.18 No.1

The mechanism of tendon healing has been a controversial issue. Although there seems to be a dipolarizing opinion regarding the tendon healing, it is well known to us that the tendon has both intrinsic and extrinsic healing capacity which has proved in vivo and in vitro studies. Tendon adhesion is a common sequella after tendon repair, particularly after the ling period of immobilization. This can be explained by one wound concept or extrinsic tendon healing. If we can modify the natural healing process of the tendon by augmenting the intrinsic capacity, we can reduce the period of immobilization to allow early motion for better gliding. in this study, we used the electrical stimulation technique, which has been known to have good growth stimulatory effect on the living cells, to investigate its effect on tendon healing in organic culture for 6 weeks. Total 64 flexor tendons were harvested from 8 rabbit paws and they were cultured in separate petri-dishes.: 32 tendons were used for the control group and the rest 32 were used for the electric stimulation group. Tendons through which a continuous 7 μAmp current was passed at the repair site were compared with the non stimulated controls. In reference to the histologic study with Hematoxylin ?? Eosin stain and van Gieson stain, the following results were obtained. 1. There was found no necrosis in the specimens of the control as well as the elctrical stimulation group during 6 weeks' culture period. 2. Starting from 1 week, there was prominent increase of fibroblastic proliferation and collagen production in electrical stimulation group and these active repair processes persisted up to 6 weeks. Accordingly, I conclude that the intrinsic tendon healing capacity can be enhanced by the electrical stimulation in vitro.

DNA Chip과 고정화 기술

박현규,지홍석,임성춘,장호남 한국화학공학회 2002 Korean Chemical Engineering Research(HWAHAK KONGHA Vol.40 No.3

DNA chip 기술은, 인간 DNA 염기 서열상의 이상징후와 관련된 질병을 진단하거나 신약 개발을 위하여 특정 DNA 발현의 분석 등에 응용될 수 있다. 현재, DNA chip을 제작하고 DNA hybridization 반응 신호를 감지하는 방법에는 다양한 기술들이 있다. 본 글에서는 급성장하고 있는 DNA 칩의 전반적인 원리, 제조기술, 그리고 DNA를 chip에 고정화 시키는 기술을 중점적으로 소개하고자 한다. 또한 젊은 나이에서의 당뇨 발병과 관련된 유전자인 MODY의 유전자 변이를 진단하는 oligonucleotide DNA chip의 예를 보여주고자 한다. The application of DNA chip technology includes the diagnosis of various human diseases associated with DNA sequence anomalies and the comprehensive analysis of expressed sequences with regard to newer drug designs. There are a variety of options for making DNA chips and detecting hybridized signals. Here, we take a close look at the principles and manufacturing technologies of this rapidly growing area, highlighting the DNA immobilization technology on the chip. Finally we present an example of oligonucleotide chip for the analysis of multiple MODY gene mutations, which are related with diabetes of the young.

油靜壓트러스트베어링의 靜特性解析

朴天弘,李厚祥 國立 昌原大學校 産業技術硏究所 1989 産技硏論文集 Vol.3 No.-

The purpose of the present paper is to analyze the load and thermal characteristics of double-pad type hydrostatic oil bearings with capillary restrictor. For the calculation of thermal effect, it is assumed that the clearance of bearing is isothermal and that the friction power is entirely converted to thermal energy. The Finite Element Method is used for the analyses. The results obtained are as follows. 1) As the recess pressure ratio is being increased, load capacity is also increasing in lower eccentricities. But the tendency is reversed in higher eccentricities respectively. 2) As the recess pressure ratio is being increased, temperature rise is decreasing. 3) The predicted temperature rise shows excellent agreement with the measured at 0.8 of convection ratio. 4) The analysis method proposed is considered to be effective to estimate the static characteristics of double-pad type hydrostatic oil bearings with rotating shaft.

국내 병원 간호사와 제조업 근로자의 직업성 요통발생에 관한 고찰

박소연,홍현숙,정춘화,김현욱 가톨릭대학산업의학센타 산업의학연구소 2002 韓國의 産業醫學 Vol.41 No.2

This article reviewed studies of occupational low back pains(LBPs) and work-related factors among hospital nurses and manufacturing workers. The main purpose was to obtain basic data for preventing work-related LBPs and developing health care policies and regulations related to LBPs. We analysed 11 studies of hospital nurses and 9 studies of manufacturing workers, which were published from 1977 to 2000 in Korea. From these studies, it was found that the lifetime prevalence rates of LBP among hospital nurses were 72.3 to 81.6%, while those for manufacturing workers were 52.9 to 68.6%. Among nurses, the 20-29 age group showed the highest LBP prevalence rate, while it was the 30-40 year-old group for manufacturing workers. The highest prevalence rates were found among manufacturing workers with sitting positions, and among hospital nurses with standing position over 7 hours a day. For nurses, tasks of patients handling and postures related to patient-transfer such as reaching, lifting, pushing, and pulling were highly correlated with the occurrence of LBPs. For manufacturing workers, occurrences of LBPs were correlated highly with material handling tasks with>25 ㎏ weight and >50 numbers of repetitions. But for nurses, transfer of heavy objects weighing more than 10 ㎏ was highly correlated with LBP occurrence. Since previous studies were focused merely on the occurrences of LBPs, future studies of occupational LBPs among nurses should address those factors that are related to the development of LBPs. And more objective evaluation tools such as ergonomic job/task analysis or postural analyses using 3D or computer/video techniques should be utilized. In addition, studies on the development of LBP prevention programs and evaluating effectiveness of ergonomic intervention programs are needed.

보건교육 내용에 관한 지식 및 흥미에 관한 연구 : 일부 사범대학생을 중심으로 Focusing on the Subjects of Teachers' University Students

홍춘실,박영신 충남대학교 의과대학 지역사회의학연구소 1988 충남의대잡지 Vol.15 No.2

This research was conducted to help select and categorize the suitable health education contents for the health curriculum and health education program. The purpose of this study is to provide a useful information about the health knowledge and health interest of teachers' university students to select a recommendable planning, scope, and contents of health education by a comparative analysis between male and female students, and between departments. The tool for this study was questionaire. The number of items is ninty, 30 of health knowledge and 60 of health interest. And they are subgrouped under eight categories. The items were worked out by me based on the contents of health education subject for general education of many colleges, and were complemented by a preliminary investigation. The subjects for this study were chosen among 548 collegians in K National Teachers' University. Data were collected for thirteen days from November 24 to December 6, 1986 and were analyzed by the SPSS computer program. The results of this study are as follows: 1. The most well-known area of health education contents regardless of sex is "Environments and Health Hazards" and the most ignorant area is "Disease Control". Comparing the degree of health knowledge between male and female students group mean score of females is significantly higher than that of males. (t=8.44, d. f=546, P<0.01) Comparing the departmental degree of health knowledge, there is no significant difference in the mean score between humanities department and natural 'science department. However, the mean score of arts and athletics department is significantly lower than that of humanities department and natural science department. (.P<0.01) 2. The most interested area among health education contents in both males and females is "Health Maintenance and Promotion", and the least interested area is "Community Health". Comparing the degree of health interest between male and females studenst, group mean score of females is significantly higher than that of males. (t=1.99, d. f=546, P<0. 01) The degree of departmental health interest in nearly same in 7 area, but the degree of health interest of arts and athletice department in "Body structure and Function" areais significantly higher than that of humanities and natural science department. (P<0.01) 3. The correlation between health knowledge and health interest is found significant only in the case of female students of natural science department. (r=0.20, P<0.05) The correlation between health knowledge and health interest is also significant in "Health Maintenance and Promotion" area : (r=0.13, P<0.01) 4. There's no significant difference in health knowledge and interest from whichever source they acquire health knowledge. Health knowledge is acquired mostly newspapers and magazines (39%).

탱자(Poncirus tripoliata RAF)잎으로부터 Mitochondrial DNA의 분리

박종필,전홍성,김연순,이숙영,김성준 조선대학교 부설 유전생물공학연구소 1992 유전생물공학연구지 Vol.2 No.-

Differaitial centrifugation, sucrose(30%, 60%) and percoll(13.5%, 21% and 45%) density gradient centrifugation were used to effectively isolate mitochondria and mitochondrial DNA (mt DNA) from the leaves of the genus Poncirus (Pondrus trifoliata RAF.) The results showed that percoll density gradient centrifugation provided a convinient and effective method for the preparation of clean mitochondria. The purity of prepared mt DNA was increased by the removal of the nuclear DNA by DNase treatment to the crude mitochondrial suspension mt DNA on the agarose gel was shown extra fluorescent background in case of isolation by differential centrifugation and more cleared band included slightly smeared patterns for sucrose density gradient, and highly paint band from percoll density gradient was appeared to the best results of the above three methods. In addition to chromosomal mt DNAs, two short mt plasmid-like elements were detected in the genus Poncirus. These elements consistently co-purified with the chromosomal mt DNAs and is widely distributed among natrual Poncirus trifoliata RAF. populations. But these elements required proteinase K treatment for mobility in agarose gels.

Bletilla striata REICHB.의 조직배양에 관한 연구

박병천,김홍섭 조선대학교 기초과학연구소 1989 自然科學硏究 Vol.12 No.1

자란(Bletilla striata R_EICNB)의 유축 생장에 미치는 질소원 및 stock solution 농도의 영향을 규명하기 위하여 1986년 5월에 인공 수분하여 10월에 채종한 종자를 3%H_2O_2에 35분간 살균하여 기본 배지레 파종하여 발아 시킨 유축을 질소원과 stock solution 농도를 달리한 배지에 이식 했을때 이들이 유축 생장에 미치는 영향을 검토 하였던 바 그 결과를 요약하면 다음과 같다. 1. 질소원에 따른 유축 생장이 초기에는 생장 조절 물질의 영향을 받는 것으로 나타났으며 기관이 분화 된 후에는 질소원에 의해서는 영향을 받는 것으로 나타났다. 2. 질소원에 따른 유축 생장은 NaNO_3를 첨가한 배지에서 양호하게 나타났으며 (NH_4)_2SO_4를 첨가한 배지에서는 불량하였다. 3. Stock solution의 농도는 2Mole을 첨가한 배지에서는 양호 하였으며 4Mole을 첨가한 배지에서는 불량하였다. 4. 생장 조절제에 따른 자란 유축 생장에 적합한 배지는 NAA 0.2mg/l+Kinetin 2.0mg/l를 첨가한 배지로 나타났다. In order to examine the effect of the concentration of nitrogen source and stock solution on growth of seedling of Bletilla striata R_EICHB the study was carried out. The seedlings were pollinated artificially in May 1986, harvested in october, sterilized for 35 minutes with 3% H_2O_2 and sowed in the media. The seedlings germinated were transplanted in the media contained several concentration of nitrogen source and stock solution. The results obtained were as follows ; 1. At first growth seedlings according to nitrogen source appeared to take effect of growth regulator, but of nitrogen source after organs developed. 2. Growth of seedlings according to nitrogen source were good when added to NaNO_3 and were bad when added to (NH_4))2 SO_4. 3. Concentration of stock solution was good for growth when added to 2 mole and was bad fro growth seedlings when added to 4 mole. 4. The suitable media on growth of seedlings of Bletilla striata R_EICHB, according to growth regulators was identified as the media contained NAA 0.2㎎/ℓ+Kinetin 2.0㎎/ℓ.

凍結深度 算定에 대한 硏究

민홍기,류제천,김송만,박춘수 忠南大學校 産業技術硏究所 1997 산업기술연구논문집 Vol.12 No.2

Korea has the ground which freezes in winter and melts in warmer seasons by turns. Therefore, in designing civil-structures or buildings on such ground, the depth of seasonal frost penetration must be considered. In this paper, approximate contours of the maximum depth of frost penetration in Korea is presented. The National Construction Research Institute of Korea has measured the depth of the frozen ground covering all the area of South Korea during the ten years ranging through 1980. The measurement were made for the frozen ground at random but intended for the most frost-susceptible soils. The contour of the maximum depth of the frost penetration is drawn on a map with data collected during the ten years. It is known that the maximum depth of the frost penetration is related to freeze index values. An empirical formula expressing the relation is suggested, in which the depth is proportional to the one-fifth power of the air freezing index values.