• Korean Journal of Microbiology
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• v.38 no.2
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• pp.96-102
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• 2002

The S-phase checkpoint mechanisms response to DNA damage or inhibition of DNA replication for maintenance of genetic stability in eukaryotic cells. These roles include cell cycle control arrest at S-phase and Iranscriptional induction of repair genes. To characterize the defects of dpbll mutant for both these responses, we examined the over-expression effect of DPBll gene, the sensitivity to HU, MMS, and the transcriptional pattern by DNA damage agent for RNRS mRNA. RNRS transcript is induced in response to a wide variety of agents that either damage D7A directly through chemical modification or induce stress by blocking DNA synthesis. As results, dpbll-1 cells are sensitive to DNA damage agents and the level of RNR3 mRNA is reduced approximately 40% than wild type cells. Moreover, we found the same results in dpb2-1 cells. Therefore, we propose that DPB2 and DPBll act as a sensor of replication that coordinates the transcriptional and cell cycle responses to replication blocks.

• Journal of the Korea institute for structural maintenance and inspection
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• v.19 no.6
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• pp.112-118
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• 2015

These days, there are lots of skyscrapers being constructed in downtown areas. However, it requires columns which have a way heavier load. and far more extensive cross sections of column as well. Therefore, it is hard to lay the foundation in downtown areas. This being the case, composite columns such as CFT column are primarily being used. However, CFT column is occurred of difficult beam-column connection development and lower performance since CFT column is closed cross-section. Especially, the result of the study concerning development of connection details with CFT column and exterior diaphragms are very low in current state. In this study, through developing CFT column-H shape steel beam applicating Y shape plate, set width and depth of Y shape plate which affect structural performance of connection details applicating Y shape plate as main variables, and evaluate structural performance through experiments. And also, design Y shape plate used at experiments as setting allowable stress for tension suggested at design criteria lower than axial force of tension side flange connected Y shape plate, through shape of destruction, verify the structural safety and performance of Y shape plate.

• Geophysics and Geophysical Exploration
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• v.4 no.2
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• pp.34-44
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• 2001

Forward modeling by construction of synthetic data is usually practiced in a horizontal surface and a few subsurface structures. However, in-situ surveys often take place in such topographic changes that the corrupted field data always make it difficult to interpret the right signals. To examine the propagation characteristic of elastic waves on the irregular surface, a general mesh generation code for finite element method was modified to consider the topography. By implementing this algorithm, the time domain modeling was practiced in some models with surface topography such as mound, channel, etc. The synthetic data obtained by receivers placed on surface also agreed with the analytic solution. The snapshots showing the total wave-field revealed the propagation characteristic of the elastic waves through complex subsurface structures and helped to identify the signals on the time traces. The transmission of Rayleigh waves along the surface, compressive waves, and sheer waves was observed. Moreover, it turned out that the Rayleigh waves behave like a new source at the edge.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2018.04a
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• pp.63-63
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• 2018

본 연구에서는 80% 식물성 알코올을 추출 용매로 사용해 오디를 빛을 차단 후 실온에서 3일 간 추출하였다. 3회 여과한 후 최소 온도($40{\sim}60^{\circ}C$)에서 농축한 뒤 동결 건조하여 파우더 형태로 사용하였다. 오디(Morus alba)의 에탄올 추출물은 B16/F10 세포의 항산화 및 멜라닌 합성 억제 효과를 나타내었다. 멜라닌 함량과 세포 내 tyrosinase 활성을 Western blotting으로 측정 하였다. Tyrosinase와 tyrosinase-related protein (TRP) -1은 tyrosinase-related protein (TRP) -2보다 강력하게 억제되었으며, 이들 결과는 tyrosinase와 TRP-1은 흑갈색을 띠는 eumelanin의 생합성의 억제와 강한 상관관계가 있음을 보여 주었다. ${\alpha}$-melanocyte-stimulating hormone (${\alpha}$-MSH) 처리 한 B16/F10 흑색 종 세포에서 M. alba 에탄올 추출물은 멜라닌 생성 연관 단백질의 발현 및 멜라닌 생성이 용량 의존적으로 억제 하였다. 멜라닌 함량과 세포 내 tyrosinase 활성을 Western blotting으로 측정 하였다. 또한 DPPH와 SOD를 사용하여 항산화 활성을 분석하였고 총 폴리 페놀과 총 플라보노이드 함량을 측정 하였다. MTT assay 분석을 사용하여 M. alba 에탄올 추출물의 세포 독성을 측정 하였다. B16/F10 멜라닌 생성 세포의 tyrosinase 저해 활성 및 사멸 효과가 일반적으로 효과적이었다. 따라서 M. alba 에탄올 추출물은 항산화 및 미백 효과를 나타내며, 기능성 화장품의 천연 성분으로서 우수한 것으로 여겨진다.

• YAKHAK HOEJI
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• v.37 no.2
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• pp.136-142
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• 1993

To a suspension of 1-cyclopropyl-6,8-difluoro-1,4-dihydro-7-{3,7-diazabicyclo[3.3.0]oct-1(5)-en-3-yl}-4-oxo-3-quinoline carboxylic acid(C1) in sodium hydroxide solution and water is added dropwise with stirring carbon disulfide. [6R-[6$\alpha$, 7$\beta$(Z)]]-7-[[[2-Amino-4-thiazoly)methoxyimino]-acetyl]amino]-3-[[[[7-( 3-carboxy-1-cyclopropyl-6,8-difluoro-1,4-dihydro-4-oxo-7-guinolonyl)-3,7-diazabicyclo[3.3.0]oct-1(5)-en-3-yl]thioxomethyl]thio]methyl]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-en-2-carboxylic acid (DACD) was synthesized from 1-cyclopropyl-6,8-difluoro-1,4-dihydro-7-[7-(mercapto) thioxomethyl-[3,7-dia zabicyclo[3.3.0]oct-1(5)-en-3-yl}]-4-oxo-3-quinoline carboxylic acid disodium salt(C2) and cefotaxime. The invitro activity of novel dual-action cephalosporin, DACD, was compared with the in vitro activities of CENO(cefotaxime 3'-norfloxacin dithiocarbamate), cefotaxime, and norfloxacin against a variety of bacterial species. In vitro activity of DACD was superior to that of norfloxacin against Streptococcus pyogenes. Against Gram-positive and Gram-negative bacteria, its activity was almost equal to that of CENO.

• Journal of the Institute of Electronics Engineers of Korea CI
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• v.43 no.2 s.308
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• pp.63-71
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• 2006

Denoising and reconstruction of color images are extensively studied in the field of computer vision and image processing. Especially, denoising and reconstruction of color face images are more difficult than those of natural images because of the structural characteristics of human faces as well as the subtleties of color interactions. In this paper, we propose a denoising method based on PCA reconstruction for removing complex color noise on human faces, which is not easy to remove by using vectorial color filters. The proposed method is composed of the following five steps: training of canonical eigenface space using PCA, automatic extraction of facial features using active appearance model, relishing of reconstructed color image using bilateral filter, extraction of noise regions using the variance of training data, and reconstruction using partial information of input images (except the noise regions) and blending of the reconstructed image with the original image. Experimental results show that the proposed denoising method maintains the structural characteristics of input faces, while efficiently removing complex color noise.

• Journal of the Institute of Electronics Engineers of Korea CI
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• v.47 no.3
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• pp.51-58
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• 2010

Since Augmented Reality (AR) enables users to experience computer-generated content embedded in real environments, AR agents can be visualized among physical objects in the environments where the users exist, and directly interact with them in real-time. We model perceptual attention for autonomous agents in AR environments where virtual and physical objects coexist. Since such AR agents must adaptively perceive and attend to surrounded objects relevant to their goals, our model allows the agents to determine currently visible objects from the description of what virtual and physical objects are configured in the camera's viewing area. A degree of attention is assigned to each perceived object based on its relevance to achieve agents' goals. The agents can focus on a reduced set of perceived objects with respect to the estimated degree of attention. To demonstrate the effectiveness of our approach, we implemented an animated character that was overlaid over a miniature version of campus and that attended to buildings relevant to their goals. Experiments showed that our model could reduce the character's perceptual loads even when surroundings change.

• Journal of the Korean Chemical Society
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• v.40 no.3
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• pp.202-208
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• 1996

SAPO-11 was synthesized hydrothermally and dealuminated with $H_4$EDTA. The framework structure of SAPO-11 was maintained safely by 24 hours' dealumination, but further dealumination for 48 hours caused SAPO-11 collapsed and to be changed to variscite($AIPO_4{\cdot}2H_2O$) and tridymite($SiO_2$). Dealuminated SAPO-11 showed two structural hydroxyl bands at 3607 $cm^{-1}$ and 3453 $cm^{-1}$ respectively. The intensities of these two bands increased according to the extent of dealumination, and disappeared by the adsorption of methylamine. Dealuminated SAPO-11 showed higher desorption temperatures and greater activation energies in desorption of water and methylamine compared to non-dealuminated SAPO-11. All the phenomena may be due to the stronger interactions of Bronsted acid sites of structural hydroxyl groups generated by dealumination with adsorbed water and methylamine molecules respectively.

• Journal of the Korean GEO-environmental Society
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• v.13 no.6
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• pp.27-31
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• 2012

This study was designed to examine the feasibility of functionalized mesoporous silica as the adsorbent for benzene, toluene, ethylbenzene, and xylene isomers (BTEX) in groundwater. p-Xylene was used as the model compound of BTEX. A series of functionalized mesoporous silica with MCM-41 type of structure was synthesized using a co-condensation method. Monoamine, triamine, nitrile, phenyl, and octyl groups were functionalized to the mesoporous silica structure. Adsorption sites for p-Xylene in a functionalized mesoporous silica were Si-O-Si covalent bond, the surfactant, and the functional group. Octyl-functionalized mesoporous silica with stearyltrimethylammonium chloride as a surfactant showed the highest adsorption ability. The maximum xylene adsorption capacity of the octyl-functionalized mesoporous silica with stearyltrimethylammonium chloride based on Langmuir model was 4.17 mmol/g on $20^{\circ}C$, which was 2.9 times higher than that of MCM-41.

• Proceedings of the Korea Concrete Institute Conference
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• 2008.04a
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• pp.933-936
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• 2008

An engineered cementitious composite (Engineered Cementitious Composite) had been developed in previous study. Theoretical prediction of the tensile stress-strain relation of ECC is important in providing the material constitutive relation necessary for designing structural members. But, few studies have been reported with regard to predicting the tensile stress-strain relation of ECC. Prediction of the tensile stress-strain relation of ECC accounting for actual bridging curve, such as fiber dispersion is needed. The present study extends the work as developed by Kanda et al., by modeling the bridging curve, accounting for fiber dispersion, the degree of matrix spalling, and fiber rupture to predict the tensile stress-strain relation of ECC. The role of material variation in the bridging curve, such as number of effective fiber actually involved in the bridging capacity and how it affects the multiple cracking process is discussed. The approach for formulating the tensile stress-strain relation is discussed next, where the procedure for obtaining the necessary parameters, such as the crack spacing, is presented. Finally, the predicted stress-strain relation will be validated with experimental tests results.