• Journal of Microbiology and Biotechnology
• /
• 제17권7호
• /
• pp.1169-1176
• /
• 2007

Genes encoding proteins responsible for limonene catabolism were cloned from a limonene-degrading microorganism, Enterobacter cowanii 6L, which was isolated from citron (Citrus junos) peel. The 8.6, 4.7, and 7.7 kb fragments (CD3, CD4, and CD6) of E. cowanii 6L chromosomal DNA that confer to E. coli the ability to grow on limonene have been cloned and their corresponding DNA sequences were determined. Nine open reading frames (ORFs) were identified, and the four ORFs (921 bp of CD3-2; 1,515 bp of CD4-1; 1,776 bp of CD6-1; and 1,356 bp of CD6-2) that encode limonene hydroxylase were confirmed by independently expressing these genes in E. coli. FAD and NADH were found to stimulate the hydroxylation reaction if added to cell extracts from E. coli recombinants, and multiple compounds (linalool, dihydrolinalool, perillyl alcohol, (${\alpha}-terpineol$, and ${\gamma}-terpineol$) were the principal products observed. Our results suggest that the isolate E. cowanii 6L has a broad metabolic capability including utilization of limonene. This broad metabolic ability was confirmed by identifying four novel limonene hydroxylase functional ORFs in E. cowanii 6L.

• 대한수학회보
• /
• 제49권4호
• /
• pp.885-898
• /
• 2012

Let m, n, r be nonzero fixed positive integers, R a 2-torsion free prime ring, Q its right Martindale quotient ring, and L a non-central Lie ideal of R. Let D : $R{\rightarrow}R$ be a skew derivation of R and $E(x)=D(x^{m+n+r})-D(x^m)x^{n+r}-x^mD(x^n)x^r-x^{m+n}D(x^r)$. We prove that if $E(x)=0$ for all $x{\in}L$, then D is a usual derivation of R or R satisfies $s_4(x_1,{\ldots},x_4)$, the standard identity of degree 4.

• Nutritional Sciences
• /
• 제9권2호
• /
• pp.82-91
• /
• 2006

This study was performed to investigate the effect of normal diet with or without naringin supplement on the lipid and antioxidant metabolism in ethanol-treated rats for a short tenn. Male Sprague-Dawley rats were divided into three groups (n=10), which were assigned to one of three dietary categories : $E_8$ : ethanol diet for 8 wks, $E_4N_4$ : ethanol diet for the first 4 wks and normal diet for the last 4 wks, $E_4Nna_4$ : ethanol diet for the first 4 wks and normal diet with naringin supplement for the last 4 wks. Plasma total cholesterol concentrations were significantly higher in ethanol fed rats for 8 weeks. The HDL-C/total-C ratios of the $E_4N_4$ and the $E_4Nna_4$ groups were significantly higher than that of the $E_8$ group, while the atherogenic index was lower in the $E_4N_4$ and the $E_4Nna_4$ groups than in the $E_8$ group. The $E_4N_4$ and $E_4Nna_4$ diets significantly lowered both the hepatic cholesterol and triglyceride levels compared to the $E_8$ group. Accumulation of hepatic lipid droplets was observed to be the highest in the $E_8$ group. In the current study, the naringin supplement to normal diet significantly lowered both the hepatic HMG-CoA reductase and ACAT activities in ethanol pre-treated rats for 4 weeks. Antioxidant enzyme activities were also upregulated when ethanol feeding was ceased. Naringin supplement given for 4 weeks after ethanol cessation resulted in a significant decrease in the plasma cholesterol and hepatic lipids and plasma TBARS as well as the hepatic HMG-CoA reductase and ACAT activities compared to the rats given ethanol diet for the entire 8 weeks. Replacement of normal diet following a short tenn ethanol feeding was effective for the recovery of ethanol-induced fatty liver and for normalizing plasma and hepatic lipid profiles and antioxidant enzyme activities, regardless of an additional phytochemical supplement, naringin. The effect of naringin could seemingly be more evident if its supplementation period had been extended longer than 4 weeks after ethanol cessation.

• Geomechanics and Engineering
• /
• 제30권6호
• /
• pp.565-577
• /
• 2022

In this study, a series of three-dimensional numerical parametric study was conducted to investigate deformation mechanisms of an existing box culvert due to an adjacent multi-propped basement excavation in clays. Field measurements from an excavation case history are first used to calibrate a baseline Hardening Soil Small Strain (HS-small) model, which is subsequently adopted for parametric study. Results indicate that the basement-box culvert interaction along the basement centerline can be considered as a plane strain condition when the length of excavation (L) reaches 14 H_e (i.e., final excavation depth). If a plane strain condition (i.e., L/H_e=12.0) is assumed for analyzing the basement-box culvert interaction of a short excavation (i.e., L/H_e=2.0), the maximum settlement and horizontal movement of the box culvert are overestimated significantly by up to 15.7 and 5.1 times, respectively. It is also found that the deformation of box culvert can be greatly affected by the basement excavation if the distance between the box culvert and retaining wall is less than 1.5 H_e. The induced deformation in the box culvert can be dramatically reduced by improving the ground inside the excavation or implementing other precautionary measures. For example, by adding jet grouting columns within the basement and installing an isolation wall behind the retaining structures, the maximum settlements of box culvert are shown to reduce by 37.2% and 13.4%, respectively.

• Biomolecules & Therapeutics
• /
• 제26권5호
• /
• pp.503-511
• /
• 2018

Triclosan (TCS) and bisphenol A (BPA) are endocrine-disrupting chemicals that interfere with the hormone or endocrine system and may cause cancer. Kaempferol (Kaem) and 3,3'-diindolylmethane (DIM) are phytoestrogens that play chemopreventive roles in the inhibition of carcinogenesis and cancer progression. In this study, the influence of TCS, BPA, Kaem, and DIM on proliferation and apoptotic abilities of VM7Luc4E2 breast cancer cells were examined. MTT assay revealed that TCS ($0.1-10{\mu}M$), BPA ($0.1-10{\mu}M$) and E2 ($0.01-0.0001{\mu}M$) induced significant cell proliferation of VM7Luc4E2 cells, which was restored to the control (0.1% DMSO) by co-treatment with Kaem ($30{\mu}M$) or DIM ($15{\mu}M$). Reactive oxygen species (ROS) production assays showed that TCS and BPA inhibited ROS production of VM7Luc4E2 cells similar to E2, but that co-treatment with Kaem or DIM on VM7Luc4E2 cells induced increased ROS production. Based on these results, the effects of TCS, BPA, Kaem, and DIM on protein expression of apoptosis and ROS production-related markers such as Bax and Bcl-xl, as well as endoplasmic reticulum (ER) stress-related markers such as $eIF2{\alpha}$ and CHOP were investigated by Western blot assay. The results revealed that TCS, and BPA induced anti-apoptosis by reducing ROS production and ER stress. However, Kaem and DIM effectively inhibited TCS and BPA-induced anti-apoptotic processes in VM7Luc4E2 cells. Overall, TCS and BPA were revealed to be distinct xenoestrogens that enhanced proliferation and anti-apoptosis, while Kaem and DIM were identified as natural chemopreventive compounds that effectively inhibited breast cancer cell proliferation and increased anti-apoptosis induced by TCS and BPA.

• 한국농공학회지
• /
• 제21권4호
• /
• pp.108-117
• /
• 1979

In order to obtain the basic data for design of water structures which can be contributed to the planning of water use. Best fitted distribution function and the equations for the probable minimum flow were derived to the annual minimum flow of five subwatersheds along Geum River basin. The result were analyzed and summarized as follows. 1. Type III extremal distribution was considered as a best fit one among some other distributions such as exponential and two parameter lognormal distribution by $x^2$-goodness of fit test. 2. The minimum flow are analyzed by Type III extremal distribution which contains a shape parameter $\lambda$, a location parameter ${\beta}$ and a minimum drought $\gamma$. If a minimum drought $\gamma=0$, equations for the probable minimum flow, $D_T$, were derived as $D_T={\beta}e^{\lambda}1^{y'}$, with two parameters and as $D_T=\gamma+(\^{\beta}-\gamma)e^{{\lambda}y'}$ with three parameters in case of a minimum drought ${\gamma}>0$ respectively. 3. Probable minimum flow following the return periods for each stations were also obtained by above mentioned equations. Frequency curves for each station are drawn in the text. 4. Mathematical equation with three parameters is more suitable one than that of two parameters if much difference exist between the maximum and the minimum value among observed data.

• 천문학회보
• /
• 제35권2호
• /
• pp.78.2-78.2
• /
• 2010

We report the detection of a low-amplitude 380.8-day radial velocity (RV) variations in oscillating K2 III star ${\alpha}$ Ari (HD 12929). We do not found the correlation between RV variations and equivalent widths of chromospheric activity indicators ($H{\alpha}$ and CaII 8662 ${\AA}line$). The bisector analysis shows that bisector velocity span (BVS) and RV variations are not strongly correlated with each other. These result suggest that the RV variations could have been produced either by planetary companion or by the surface spots. If this RV variation is indeed caused by a planetary companion, an orbital solution with a period of P = 381 days, a semi-amplitude of K = 41 m/s, and an eccentricity of e = 0.25 fits the data best. Assuming a possible stellar mass of $M_{\bigstar} = 1.4-5.6 M\odot$, we estimate the minimum mass for the companion of m sini = 1.8-4.5 $M_{Jup}$ with an orbital semi-major axis of 1.2-1.9 AU. If confirmed, our finding gives a support to search for exoplanets around giant stars with multi-periodic oscillations.

• 경영과정보연구
• /
• 제19권
• /
• pp.199-221
• /
• 2006

The purpose of this study is to expand businesses' adoption of the Enterprise Resource Planning System (E.R.P.S.). In order to accomplish the objective, the following conditions need to be fulfilled. 1) Clearness of the goal and expected effect of E.R.P.S. adoption 2) Definiteness of the extent of E.R.P.S. construction 3) The management's will to E.R.P.S. adoption If the E.R.P.S is adopted, the following effects are expected. 1) Speedy quality decision-making is possible. 2) Time taken from the order of the product to its release can be curtailed (from 40days to 10days). 3) Time taken for the development of the product can be shortened (from 24 months to 10 months). 4) Cost reduction is possible by using necessary information in real time.

• 한국시스템다이내믹스연구
• /
• 제10권4호
• /
• pp.5-25
• /
• 2009

Since the end of the 1950-1953 Korean War, many scholars and policymakers have expressed concern about the possibility of another conflict on the peninsula. In certain respects, the post-1953 North-South Korea relationship resembles the Cold War that existed between the United States and the Soviet Union, 1945-1990. Although a "hot" never occurred, peace was never guaranteed. By looking at international theories (i.e., realism and liberal theory) and by utilizing casual-loop diagram analysis, the main purpose of this research is to explore on the likelihood of peace and war on the Korean peninsula. First, several factors (e.g., economic stagnation of North Korea, unstable political systems, and so on) emphasized by realism perspectives are significantly related to the likelihood of conflict between North and South Korea. Conversely, several determinants (e.g., economic assistance to North Korea, inter-dialogue between two Koreas, cultural and social exchange, and so on) emphasized by liberal approaches are significantly related to likelihood of peace on the Korean peninsula. Given the two different interpretations about the likelihood of conflict or peace, it can be argued that a second military action might occur on the Korean peninsula if realism theories are true. However, if practical factors exist on the Korean peninsula, the two Korean can optimistically expect a peaceful reunification in the future, without interference from other countries.

• 한국인터넷방송통신학회논문지
• /
• 제17권4호
• /
• pp.173-179
• /
• 2017

오토바이는 자동차에 비해 차량주행정보가 부족하고 사고 위험성이 높아 충돌감지센서, 후방카메라, 블루투스 통신모듈, 마이크로콘트롤러, HUD로 구성되는 스마트헬멧을 제작하여 오토바이 주행정보와 e-call 기능을 제공하는 시스템을 개발한다면 사용자에게 매우 유용하고 교통사고 시에 인명피해 감소 및 신속한 교통사고 처리가 가능하다. 본 논문에서는 이와 같은 "스마트헬멧을 이용한 오토바이 운전자 주행정보 및 e-call 기능 제공 시스템"의 소프트웨어를 개발하는데 있어 객체지향 분석 방법인 UML을 이용한 소프트웨어 개발 분석 방법, 하드웨어 블록다이어 그램 구조, 플로우차트 및 UI 설계를 보여줌으로써 실무 개발에 적합한 분석/설계 방법을 제시하고자 한다.