A Numerical Analysis on Three-Dimensional Flow Field in a Supersonic Bump-Type Inlet

Sang Dug Kim,Dong Joo Song 대한기계학회 2007 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.21 No.2

The characteristic of a supersonic inlet system with three-dimensional bump which is substituted for the diverter or conventional ramp-type compression systems has been studied numerically. A comprehensive numerical analysis has been performed to understand the three-dimensional flow field including shock/boundary layer interaction and growth of turbulent boundary layer that might occur around a three-dimensional bump in a supersonic inlet. The current numerical simulations showed the supersonic bump-type inlet which is modified from a conventional ramp-type inlet to control shock/boundary layer interaction effectively and evolved to maximize inlet performance.

Effects of herbicide tolerance rice cultivation on microbial community in paddy soil

Sung-Dug Oh,Tae-Hun Ryu,Soo-In Sohn,Chang-Gi Kim,Kyoungwhan Back,Kijong Lee 한국육종학회 2013 한국육종학회 심포지엄 Vol.2013 No.07

Rice (Oryza sativa) is the most important staple food of over half the world’s population. This study was conducted to evaluate the possible impact of transgenic rice cultivation on the soil microbial community. Microorganisms were isolated from the rhizosphere of GM and non-GM rice cultivation soils. Microbial community was identified based on the culture-dependent and molecular biology methods. The total numbers of bacteria, fungi, and actinomycete in the rhizosphere soils cultivated with GM and non-GM rice were similar to each other, and there was no significant difference between GM and non-GM rice. Dominant bacterial phyla in the rhizosphere soils cultivated with GM and non-GM rice were Actinobacteria, Firmicutes, and Proteobacteria. The microbial communities in GM and non-GM rice cultivated soils were characterized using the denaturing gradient gel electrophoresis (DGGE). The DGGE profiles showed similar patterns, but didn’t show significant difference to each other. DNAs were isolated from soils cultivating GM and non-GM rice and analyzed for persistence of inserted gene in the soil by using PCR. The PCR analysis revealed that there were no amplified protox gene in soil DNA. These data suggest that transgenic rice does not have a significant impact on soil microbial communities, although continued research may be necessary.

CVX 저항성 삼각주의 미생물 군집에 미치는 영향

Sung-Dug Oh,Doh-Won Yun,Soo-Yun Park,So Youn Won,Jong-Bum Kim,Soo-In Sohn,Bum Kyu Lee,Ancheol Chang,Kijong Lee 한국국제농업개발학회 2016 韓國國際農業開發學會誌 Vol.28 No.4

There are studies on the assessment of non-edible transgenic plants on soil microbial communities. In this research we evaluated the effect of virus-resistant trigonal cactus on soil microbial communities of the rhizosphere. Soil samples are collected and compared in genetically modified (GM) and non-GM trigonal cactus cultivation fields during vegetative growth period and post-harvest period. Biolog EcoplateTM was used to evaluate the functional diversity of soil microbial communities. There were no significant differences between the GM and non-GM soil samples collected during the vegetative growth period. However, we observed temporary difference in carbon substrate utilization. Principal component analysis showed that soil microbiota was influenced not by presence of GM or non-GM trigonal cacti, but rather by the cultivation period. Denaturing gradient gel electrophoresis fingerprinting revealed that virus-resistant trigonal cactus cultivation had insignificant effect on soil microbial communities including dominant rhizosphere bacteria, actinomycetes, and fungi. We found no clear evidence of GM trigonal cactus cultivation affecting the functional diversity of soil microbial communities.

Effect of the activated Raf protein kinase on the human multidrug resistance 1 (MDRI) gene promoter

Kim, Sun-Hee,Lee, Sang-Hoon,Kwak, Nam-Hee,Kang, Chi-Dug,Chung, Byung-Seon 부산대학교 유전공학연구소 1996 분자생물학 연구보 Vol.12 No.-

Revealing the regulatory mechanism of the multidrug resistance 1 (MDRI) gene is important to gain understanding of MDR in tumor cells. Using MDRI deletion constructs and the 22W mutant of c-Raf in which the NH_2-terminal half has been deleted, we examined the effect of the activated Raf on human MDRI promoter activity in transient expression assay and stable transfectants of GHE-L cells. A DNA sequence exhibiting strong activation of MDRI promoter by 22W was located between -197 and -136 containing the upstream heat shock element (HSE) motifs without other regulatory elements, whereas the MDRI deletion construct containing downstream HSE motif showed a relatively weaker activation by 22W. We observed that the activated Raf significantly potentiated the induction of MDRCAT activity in GHE-L cells by sodium arsenite or heat shock, which stimulates heat shock factor (HSF) binding to HSE. In addition, protein kinase A inhibitor (H-87) blocked the activation of the MDRI promoter by 22W in GHE-L cells in a dose-dependent manner. From these results, we propose the possibility that Raf-and protein kinase A-dependent pathways control the transcription of MDRI gene via a mechanism involving the modulation of HSF activity.

Simulation of Aeroelastic Flow Control System for Shock/Boundary Layer Interactions

Kim, Sang-Dug,Song, Dong-Joo 嶺南大學校 工業技術硏究所 2004 工業技術硏究所論文集 Vol.32 No.1

A novel flow-control method called mesoflaps for aeroelastic recirculation transpiration was computationally investigated for shock/boundary layer interactions. The numerical approach was first validated for three different ramp SBLI flows with a solid wall, in terms of both pressure distribution and velocity profiles. For the mesoflap flow-control method, a series of deflected flaps is placed over a cavity centered beneath the inception point of a shock. The flow-control performance was investigated by measuring total pressure recovery and integral boundary layer displacement thickness for a variety of pre-set flap deflection magnitudes and incoming Mach numbers. The control of an SBLI for a 16° compression corner with mesoflaps and incoming Mach numbers of 2.35-2.85 revealed significant improvement in total pressure recovery as compared to the solid-wall case, especially as the deflections of the flaps increased. The lowest incoming Mach number investigated yielded the highest recovery of total pressure downstream of the shock. Although the flap cases yielded some increases in the displacement thickness and momentum thickness of the outgoing boundary layer as compared to the solid wall, the shape factor was maintained at approximately the same level as found for the solid-wall case.

Comparison of Turbulence Models in Shock-Wave/ Boundary- Layer Interaction

Kim, Sang-Dug,Kwon, Chang-Oh,Song, Dong-Joo The Korean Society of Mechanical Engineers 2004 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.18 No.1

This paper presents a comparative study of a fully coupled, upwind, compressible Navier-Stokes code with three two-equation models and the Baldwin-Lomax algebraic model in predicting transonic/supersonic flow. The k-$\varepsilon$ turbulence model of Abe performed well in predicting the pressure distributions and the velocity profiles near the flow separation over the axisymmetric bump, even though there were some discrepancies with the experimental data in the shear-stress distributions. Additionally, it is noted that this model has y$\^$*/ in damping functions instead of y$\^$+/. The turbulence model of Abe and Wilcox showed better agreements in skin friction coefficient distribution with the experimental data than the other models did for a supersonic compression ramp problem. Wilcox's model seems to be more reliable than the other models in terms of numerical stability. The two-equation models revealed that the redevelopment of the boundary layer was somewhat slow downstream of the reattachment portion.

Assessment of Effects of GM Rice Bt-T on the Diversity of Non-target Insects

Sung-Dug Oh,Minwook Kim,Chang Uk Eun,Young-Kun Kim,Dongmin Kim,Donguk Kim,Junyeong Woo,Soon Ki Park,Sang Jae Suh 한국응용곤충학회 2023 한국응용곤충학회 학술대회논문집 Vol.2023 No.04

Unintended polar metabolite profiling of carotenoid-biofortified transgenic rice reveals substantial equivalence to its non-transgenic counterpart

Kim, Jae Kwang,Park, Soo-Yun,Lee, Si Myung,Lim, Sun-Hyung,Kim, Hyo Jin,Oh, Sung-Dug,Yeo, Yunsoo,Cho, Hyun Suk,Ha, Sun-Hwa 한국식물생명공학회 2013 Plant biotechnology reports Vol.7 No.1

Substantial equivalence is a critical concept for biosafety assessment of genetically modified (GM) crops. To investigate substantial equivalence among carotenoid-biofortified GM rice and five conventional rice cultivars having common white (three) and red (two) grain colors, profiles of 52 polar metabolites were analyzed using gas chromatography time-of-flight mass spectrometry. The results were compared to evaluate the differences among GM and non-GM rice cultivars using principal components analysis. The GM rice is more comparable to its nontransgenic counterpart rice variety according to the closer co-separation than for other cultivars tested. This suggests that profiling of unintended polar metabolites could be a useful tool to reveal substantial equivalence of GM rice.

Antioxidant Effect of Leaf, Stem, and Root Extracts of Zingiber officinale as Cosmetic Materials

Sang Moo Lee,Chun Dug Kim 한국피부과학연구원 2021 아시안뷰티화장품학술지 Vol.19 No.1

목적: 최본 연구에서는 생강 잎, 줄기, 뿌리 추출물을 응용하여 화장품 소재로서의 가능성을 평가하고자 한다. 방법: 생강 잎, 줄기, 뿌리 추출물의 화장품 소재로의 가능성을 확인하기 위해 항산화효과를 확인하기 위해 DPPH 라디컬 소거능, 총 폴리페놀 및 플라 보노이드 함량, ABTS 라디칼 소거능, SOD 유사활성을 측정하였다. 그리고 H2O2에 의해 유발되는 산화적 스트레스에 대한 HaCaT 세포 보호효과를 확인하였으며, 마지막으로 모유두 세포 증식효과를 확인하였다. 결과: 첫째, 항산화 효과 실험 결과, DPPH 라디 칼 소거능을 측정한 결과 400 μg/mL의 농도에서 생강 잎 추출물은 88.78%, 줄기 추출물은 70.12%, 뿌리 추출물은 65.52%으로 확 인되었으며, 총 폴리페놀 함량은 생강 잎, 줄기, 뿌리 추출물은 각각 170.22, 120.27, 146 μg/mL으로 확인되었으며, 총 플라보노 이드는 각각 98.52, 70.26, 46.12 μg/mL의 함량이 확인되었다. ABTS radical 소거능을 측정한 결과 400 μg/mL의 농도에서 생강 잎, 줄기, 뿌리 추출물은 각각 88.26, 70.73, 64.13%으로 확인되었으며, SOD 유사활성 측정결과 생강 잎, 줄기, 뿌리 추출물은 각 각65.22, 57.53, 50.21%의 소거능이 확인되었다. 둘째, 과산화수소로 유도된 HaCaT 세포의 산화적 손상에 대한 보호효과는 100 μg/mL 농도에서 생강 잎 추출물은 82.18%, 줄기 추출물은 78.98%, 뿌리 추출물은 70.27%의 생존율이 확인되었다. 실험 결과 생 강 잎 추출물이 32%의 증가율을 나타냄으로써 과산화수소로 유도된 세포 손상에 대해 보호효과가 높게 확인되었다. 셋째, 모유두 세포 증식효과는 생강 잎, 줄기, 뿌리 추출물을 72시간 배양한 결과 100 μg/mL 농도에서 생강 잎 추출물은 158.63%, 줄기 추출물 은 140.41%, 뿌리 추출물은 132.40%까지 세포 증식효과를 확인할 수 있었다. 결론: 이상의 연구 결과 생강 부위별 추출물 중 잎 추 출물이 항산화효과, HaCaT 세포 보호효과, 모유두 세포 증식효과가 가장 우수하여 화장품 소재 개발로 충분한 가능성이 있음을 확 인하였다. Purpose: In this study, we used Zingiber officinale (Z. officinale ) leaf, stem, and root extracts to evaluate their potential as cosmetic materials. Methods: We measured DPPH radical-scavenging activity, total polyphenolic and flavonoid contents, ABTS radical scavenging activity, and SOD-like physiological activity to confirm the antioxidant effect to assess the potential of Z. officinale leaf, stem, and root extracts as cosmetic materials. Furthermore, the protective effect on oxidative stress caused by H2O2 in HaCaT cells and proliferative effect in dermal papilla cells were assessed. Results: As a result of the antioxidant effect of Z. officinale leaf, stem, and root extracts, DPPH radical-scavenging activity was measured at a concentration of 400 μg/mL, and it was 88.78% in Z. officinale leaf extract, 70.12% in stem extract, and 65.52% in root extract. Total polyphenolic content was 170.22 μg/mL (leaf), 120.27 μg/mL (stem), and 146 μg/mL (root), whereas total flavonoid content was 98.52 μg/ mL (leaf), 70.26 μg/mL (stem), and 46.12 μg/mL (root). ABTS radical scavenging activity was measured at a concentration of 400 μg/mL, and it was 88.26% (leaf), 70.73% (stem), and 64.13% (root). Further, SOD-like physiological activity was 65.22% (leaf), 57.53% (stem), and 50.21% (root). The protective effect on oxidative stress caused by H2O2 in HaCaT cells was 82.18% (leaf), 78.98% (stem), and 70.27% (root) at a concentration of 100 μg/mL. Our results confirmed that Z. officinale leaf extract has high protective effects on cell damage caused by H2O2, showing a 32% increase. Moreover, the proliferative effect in dermal papilla cells was 158.63% (leaf), 140.41% (stem), and 132.40% (root) when cells were cultured for 72 h at a concentration of 100 μg/mL. Conclusion: Thus, Z. officinale leaf extract has the highest antioxidant effect, HaCaT cell protective effect, and proliferative effect in dermal papilla cells, indicating a possibility to be developed as a cosmetic material.

Overexpression of PRAT1 protein is closely related to triple-negative breast cancer

Sang Eun Nam,Young-Sin Ko,Kyoung Sik Park,TongYi Jin,Young-Bum Yoo,Jung-Hyun Yang,Wook-Youn Kim,Hye-Seung Han,So-Dug Lim,Seung Eun Lee,Wan-Seop Kim 대한외과학회 2022 Annals of Surgical Treatment and Research(ASRT) Vol.103 No.2

Purpose: Triple-negative breast cancer (TNBC) is an aggressive subtype of breast cancer with a poor prognosis and a lack of targeted therapy. Overexpression of PRAT1 is thought to be associated with this aggressive subtype of cancer. Here, we performed a comprehensive analysis and assessed the association between overexpression of PRAT1 and TNBC. Methods: First, using different web-based bioinformatics platforms (TIMER 2.0, UALCAN, and GEPIA 2), the expression of was assessed. Then, the expression of the PRAT1 protein and hormone receptors and HER2 status were assessed by immunohistochemical analysis. For samples of tumors with equivocal immunoreactivity, we performed silver in situ hybridization of the HER2 gene to determine an accurate HER2 status. Next, we used the R package and bc-GenExMiner 4.8 to analyze the relationship between PRAT1 expression and clinicopathological parameters in breast cancer patients. Finally, we determined the relationship between PRAT1 overexpression and prognosis in patients. Results: The expression of PRAT1 in breast cancer tissues is significantly higher than in normal tissue. PRAT1 expression was significantly related to worse overall survival (P < 0.05) and was correlated with these clinicopathological features: T stage, N stage, age, high histologic grade, estrogen receptor status, progesterone receptor status, Her-2 status, TNBC status, basal-like status, CK5/6 status, and Ki67 status. Conclusion: PRAT1 was overexpressed in breast cancer compared to normal tissue, and it may be involved in the progression of breast cancer malignancy. This study provides suggestive evidence of the prognostic role of PRAT1 in breast cancer and the therapeutic target for TNBC.