• The Korean Journal of Zoology
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• v.39 no.3
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• pp.231-238
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• 1996

Several types of human lung and pancreatic carcinoma cell lines were cultured and their chromosomal DNAs were extracted. These DNAs were then partially amplified by PCR (Polymerase Chain Reaction) and sequenced to analyze the types and frequency of mutations, and their possible relation in the oncogene, K-ras and suppressor gene, p53. Regardless of the cell line origin, 81% were found to possess at least one mutation. Among the cell lines analyzed, 54.5% of the mutations were found in either K-ras or p53. Except for one nonsense mutation, all mutations were missense with either base insertions or substitutions. Furthermore, besides the p53 codons Known to be mutated simultaneously with' ras to enhance tumor growth, p53 164-165 and 248 were found to be mutated simultaneously with K-ms. Regardless of the site of p53 mutation, all K-ras mutations found in these cases occurred at exon 1, codon 12.

• Korean Journal of Veterinary Research
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• v.42 no.4
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• pp.505-512
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• 2002

대장균 K99 섬모의 생합성은 8개로 구성된 K99의 특이 유전자의 발현과 숙주유래 인자에 의해 조절되는 다른 유전자들의 발현에 의존된다. 본 연구에서는 K99섬모 유전자군중 제 3지역 발현에 유전조절자의 관련성 여부를 연구하였다. Gel retardation 분석 방법올 통하여 제3지역의 발현에 관련된 유전조절단위를 함유한 fanF 지역의 단백질 인자가 부착됨을 암시하였다. 이 분석방법을 이용한 결과는 또한 이 단백질 인자가 K99 유전자에서 유래되지 않고 대장균 염색체에서 유래됨을 지적하였다. 이를 보다 더 조사하기 위하여 대장균 염색체에 Tn10 transposon 유전자 변이 실험을 수행하였다. K99 유전자군으로부터 제 1지역과 제2지역의 유전자를 제거시키고, 제 3지역의 유전자인 fanG에 transposon TnlacZ를 삽입한 pTL65-1 plasmid을 제작하였다. 이 pTL65-1는 다시 Tn10으로 염색체가 변이된 대장균에 주입하였다. 3개의 pTL65-1 주입된 Tn10 대장균 변이체 내에서 fanG의 발현이 증가되었다. 이들 변이대장균으로부터 Tn10이 어떤 염색체 유전자 부위를 변이 시켰는지 확인하기 위해서 변이부위 유전자를 cloning하여 염기서열을 분석하였다. 이중 2개의 clone이 동일하였으며 지금까지 알려지지 않은 유전자였다. 이들 2개의 변이체 내에서 fanG의 발현은 대조군과 비교해 약 4.2배 증가 되였다. 결론적으로 이들 2개의 clone으로부터 유래된 인자는 지금까지 알려지지 않은 제 3지역의 억제 조절자임을 나타내었다.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.31 no.3
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• pp.311-317
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• 1986

To obtain the basic informations on the variation of rice grain shattering under different environmental conditions, several experiments were carried out from 1982 to 1985. The degree of grain shattering was significantly differed depending upon the harvesting time after heading in some rice varieties. It appeared that the ratio of grain shattering was greatly affected by the drying period after harvesting; the ratio of grain shattering of sun-dried seeds for 6 days after harvesting was higher than those of the just harvested seeds. Grain shattering was increased at high level of nitrogen and decreased with delay in transplanting date. Yearly differences in grain shattering was more clearly recognized in easy-shattering varieties in comparison with those of non-shattering varieties. Rice grain shattering also increased by the low temperature treatment (l7/15$^{\circ}C$, day/night) at booting stage, 5 to 11 days before heading. A rice variety, Milyang 23, belong to easy shattering group was more pronounced at the low temperature condition with shading. In general, it was always possible to classify the cultivar differences between easy-shattering and non-shattering groups regardless of any environmental condition. Thus results suggested that rice grain shattering will be largely governed by genetic factors.

• Korean journal of food and cookery science
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• v.14 no.5
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• pp.475-481
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• 1998

This study was performed to determine the mutagenicity of pork and ham pot-stew and the anti-mutagenicity of various additive materials on pot-stew by the Ames test using Salmonella typhimurium TA100. Boiled kimchi didn't show mutagenicity and effectively inhibited the mutagenicity induced by 4-NQO and Trp-p-1. But boiled pork and ham showed mutagenicity dose-responsively and pork's mutagenicity was higher than that of ham. On the mutagenicity of boiled pork and ham, the inhibition of kimchi was most effective and when scallion and galic was added with mushroom showed synergic effect. Boiled ham made in USA did not show mutagenicity different from ham made in Korea because of the addtion of ascorbic acid and when mutagen was added it's mutagenicity was lower than that of ham made in Korea.

• Journal of Korean Society of Forest Science
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• v.94 no.6
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• pp.397-401
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• 2005

Homoharringtonine isolated from the plumyew tree (Cephalotaxus koreana) is currently considered as one of the most promising chemotherapeutic agents for anti-cancer. Variation of homoharringonine contents from eight natural populations of Korean native plumyew trees was determined by HPLC (high performance liquid chromatography), and compared with the variation among populations, the variation of the different parts(needle, root, stem and seed), and the variation according to their ages and growth features. Homoharringonine contents among populations were significantly different with Mt. South Dukyu ($1,048{\mu}g/g$) having the highest and Mt. Obong having the lowest. The analyses of plant pans showed that the homoharringtonine contents were highest in plant needles ($874{\mu}g/g$), and followed by roots, stems and seeds. Homoharringtonine contents of the plumyew trees decreased about 30% in increment with their ages and growth.

• Korean journal of applied entomology
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• v.50 no.4
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• pp.325-333
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• 2011

This study focused on the green peach aphid, Myzus persicae, as an indicator pest in Chinese cabbage cultivation to develop a genetic marker. We hypothesized that M. persicae gene flow is related to climate change. Genetic variation was analyzed using five local populations collected at different altitudes (157 m, 296 m, 560 m, 756 m and 932 m above sea level) in Hoengseong, Pyeongchang, and Gangneung areas, plus a laboratory strain used as an outgroup. There were no differences in ecological characteristics among strains. Esterase isozyme pattern and inter-simple sequence repeat (ISSR) PCR results showed significantly different bands between laboratory and wild, local populations. However, there was no difference among local populations. Partial fragments of ribosomal RNA (rRNA) and mitochondrial cytochrome oxidase I (mtCO I) were amplified and their nucleotide sequence was analyzed. Single nucleotide polymorphisms (SNPs) were detected in internal transcribed spacer-2 (ITS-2) and mtCO I regions among the five local populations. These SNPs can be use to discriminate different populations of M. persicae to monitor gene flow.

• Journal of the Korean GEO-environmental Society
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• v.9 no.4
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• pp.53-61
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• 2008

Various components including wave scattering, wave passage, and site amplification effects cause the ground motion to vary spatially. The spatially varying ground motion can significantly influence the dynamic response of longitudinal structures such as bridges and tunnels. While its effect on bridges has been extensively studied, there is a lack of study on its effect on underground tunnels. This paper develops a new procedure for simulating the tunnel response under spatially varying ground motion. The procedure utilizes the longitudinal displacement profile, which is developed from spatially variable ground motion time histories. The longitudinal displacement profile is used to perform a series of pseudo-static three dimensional finite element analyses. Results of the analyses show that the spatially variable ground motion cause longitudinal bending of the tunnel and can induce substantial axial stress on the tunnel lining. The effect can be significant at boundaries at which the material properties of the ground change in the longitudinal direction.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.31 no.1
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• pp.51-59
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• 2021

The deep learning model can produce false prediction results due to inputs that deviate from training data through variation, which leads to fatal accidents in areas such as autonomous driving and security. To ensure reliability of the model, the model's coping ability for exceptional situations should be verified through various mutations. However, previous studies were carried out on limited scope of models and used several mutation types without separating them. Based on the CIFAR10 data set, widely used dataset for deep learning verification, this study carries out reliability verification for total of six models including various commercialized models and their additional versions. To this end, six types of input mutation algorithms that may occur in real life are applied individually with their various parameters to the dataset to compare the accuracy of the models for each of them to rigorously identify vulnerabilities of the models associated with a particular mutation type.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.30 no.6A
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• pp.581-590
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• 2010

This study introduces a layered sectional analysis for a PSC girder with a vaiable cross section and curved tendons. To consider the shear equilibrium at a concrete layer with curved tendons, the shear stress distribution has been computed at each section. In addition, to improve the convergence to the solution, a system identification technique is newly adopted in the solution process for strain computation. To examine the feasibility of the proposed approach, a static load test has been conducted for a full scale PSC girder with variable cross section. The prediction shows a good agreement with experiment. It is seen that a uniform cross section has the same moment capacity with a variable cross section while the variable cross section has more shear capacity than the uniform cross section. It is also noted that the maximum displacement of a variable cross section is a little smaller than a uniform cross section.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2008.11a
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• pp.215-218
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• 2008

본 논문에서는 스테레오 카메라로부터 획득된 좌, 우 영상의 변이를 추정하여 3차원 공간 좌표(x, y, z)를 얻어내고, 거리측정과 가상공간 제어를 통해 사용자에게 현실감을 제공하는 실시간 3차원 공간 인식 시스템을 제안한다. 스테레오 카메라로 부터 획득된 좌, 우 영상은 시점의 차이 때문에 동일 물체에 대한 좌, 우 영상의 좌표 값의 차이를 발생시키는 데 이를 변이(disparity)라 정의한다. 관심 영역의 변이를 추정할 때 일반적으로 관심 영역의 모든 화소(pixel)의 변이를 추정하지만, 제안한 알고리즘에서는 관심 영역의 2차원 중심 좌표(x, y)의 변이만을 추정하여 계산량을 줄이고 실시간 처리가 가능하도록 하였다. 카메라 파라미터를 이용하여 획득된 변이로부터 깊이 정보(depth)를 얻어내고 3차원 공간 좌표를 획득한다. 손을 관심 영역으로 설정한 시스템에서 3차원 공간 좌표는 실시간으로 사용자의 손의 움직임에 의해 획득되고, 가상공간(virtual space)에 적용되어 사용자가 가상공간을 조작할 수 있는 듯한 느낌을 준다. 실험을 통해 제안한 알고리즘이 1.5m 거리 내에서의 깊이 측정시 평균 0.68cm의 오차를 가짐을 확인 할 수 있었다.