Ultrasonic Degradation of Endocrine Disrupting Compounds in Seawater and Brackish Water

So Young Park,Jong Sung Park,Ha Yoon Lee,Ji Yong Heo,Yeo Min Yoon,Kyung Ho Choi,Nam Guk Her 대한환경공학회 2011 Environmental Engineering Research Vol.16 No.3

In this study, a series of experiments was conducted on the relative degradation of commonly known endocrine-disrupting compounds such as bisphenol A (BPA) and 17α-ethinyl estradiol (Ee₂) in a single-component aqueous solution using 28 and 580 kHz ultrasonic reactors. The experiments were conducted with three different types of model water: deionized water (DI), synthetic brackish water (SBW), and synthetic seawater (SSW) at pH 4, 7.5, and 11 in the presence of inert glass beads and humic acids. Significantly higher sonochemical degradation (93-97% for BPA) occurred at 580 kHz than at 28 kHz (43-61% for BPA), regardless of water type. A slightly higher degradation was observed for Ee₂ compared to that of BPA. The degradation rate of BPA and Ee₂ in DI water, SBW, and SSW after 30 min of ultrasound irradiation at 580 kHz increased slightly with the increase in pH from 4 (0.073-0.091 min-1 for BPA and 0.081-0.094 min-1 for Ee₂) to 7.5 (0.087-0.114 min-1 for BPA and 0.092?0.124 min-1 for Ee₂). In contrast, significant degradation was observed at pH 11 (0.149-0.221 min-1 for BPA and 0.147-0.228 min-1 for Ee₂). For the given frequencies of 28 and 580 kHz, the degradation rate increased in the presence of glass beads (0.1 mm and 25 g) for both BPA and Ee₂: 0.018-0.107 min-1 without beads and 0.052-0.142 min-1 with beads for BPA; 0.021-0.111 min-1 without beads and 0.054-0.136 min-1 with beads for Ee₂. A slight increase in degradation of both BPA and Ee₂ was found as the concentration of dissolved organic carbon (DOC, humic acids) increased in both SBW and SSW: 0.107-0.115 min-1 in SBW and 0.087-0.101 min-1 in SSW for BPA; 0.111-0.111 min-1 in SWB and 0.092-0.105 min-1 in SSW for Ee₂. After 30 min of sonicating the humic acid solution, DOC removal varied depending on the water type: 27% (3 mg L-1) and 7% (10 mg L-1) in SBW and 7% (3 mg L-1) and 4% (10 mg L-1) in SSW.

Protective Effects of N-acetylcystenine and Selenium against Doxorubicin Toxicity in Rats

Yeo-sung Yoon,Sun-don Kim,Min-hye Lee,Heung-shik S.Lee,In-se Lee,Je-kyung Sung,Eun-sung Park 대한수의학회 2003 Journal of Veterinary Science Vol.4 No.2

Effects of N-acetylcysteine and Selenium against Doxorubicin Toxicity in RatsEun-sung Park, Sun-don Kim1, Min-hye Lee, Heung-shik S. Lee, In-se Lee, Je-kyung Sung and Yeo-sung Yoon*

극미량 농도 물질의 측정 및 활성탄 흡착 처리

이성범(Sung Bum Lee),윤여민(Yeo Min Yoon),최창규(Chang Kyoo Choi),정진욱(Jin Wook Jung),이용우(Yong Woo Lee),박세용(Se Yong Park),김문일(Moon Il Kim) 大韓環境工學會 2008 대한환경공학회지 Vol.30 No.9

액체섬광계수기(LSC)를 이용한 극미량의 14C-NDMA의 측정과 이를 이용해 활성탄 흡착 처리 가능성을 알아보았다. 14C-NDMA를 측정하기 위한 시료와 섬광용액은 10:10의 혼합비율로 10분의 측정 시간으로 99.9%의 상관성과 재현성을 보이며 1 ng/L까지의 측정이 가능하였으며, S-A(Sigma-Aldrich co.)와 Dj(Daejung co.)의 분말활성탄을 이용하여 흡착 처리한 결과, 50∼10,000 mg/L의 분말활성탄을 주입하여 90% 이상의 흡착처리가 가능함을 보였다. 또한 S-A가 Dj보다 흡착능이 약 2배 높게 나타났지만, NDMA의 흡착력이 다른 아민 계열의 물질보다 현저하게 낮아 요구되는 분말활성탄의 농도가 높게 요구되었다. Since the difficulty of analysis at low concentration and the uncertainty of the removal mechanism for Nitrosodimethylamine (NDMA) have been reported, this study has detected extremely low concentration 14C-NDMA using the LSC(Liquid Scintillation Counter) and tested NDMA removal by Powdered Activated Carbon(PAC). The results showed the highest correlation over 99% when samples were measured with the mixture ratio of sample to scintillation liquid of 10:10 and at the detection time of 10 min. For 14C-NDMA removal by the PACs(S-A(Sigma-Aldrich co.) and Dj(Daejung co.)) raging from 50∼10,000 mg/L, 14C-NDMA was removed over 90% by adsorption treatment. In addition, S-A showed twice greater adsorption capacity than that of Dj. However, the required PAC amount for 14C-NDMA removal was higher than that of other amine compounds.

변환된 자기회귀이동평균 모형에서의 예측구간추정

조혜민,오승언,여인권,Cho, Hye-Min,Oh, Sung-Un,Yeo, In-Kwon 한국통계학회 2007 응용통계연구 Vol.20 No.3

시계열자료를 분석하는데 있어 중요한 목적 중에 하나가 미래값에 대한 예측이다. 일반적으로 자기회귀이동평균모형에서는 백색잡음이 정규분포를 따른다는 가정 하에서 모수의 추론과 예측 및 예측구간의 추정이 이루어지고 있다. 그러나 자료가 이러한 가정을 만족하지 않는 경우, 자료를 가정에 맞게 변환시킨 후 분석하는 방법을 생각해 볼 수 있다. 이 논문에서는 변환된 자료를 분석하여 얻은 결과를 이용하여 본래의 척도에서의 미래값에 대한 예측구간을 추정하는 문제에 대해 알아본다. 제안하는 방법에서는 먼저 적절한 변환을 이용하여 자료를 정규가정을 만족하도록 변환시키고 변환된 자료를 이용하여 미래값에 대한 예측구간을 추정한 후, 역변환을 이용하여 예측구간을 추정한다. 이 논문에서는 시계열분석에서 모델링이 상대적으로 어려운 왜도의 문제를 해결하기 위해 Yeo-Johnson 변환을 중심으로 한 방법론을 소개한다. 모의실험 결과 제안된 방법에 의한 단측예측구간의 포함확률이 변환을 사용하지 않은 구간보다 명목수준에 가까운 것을 확인하였다. One of main aspects of time series analysis is to forecast future values of series based on values up to a given time. The prediction interval for future values is usually obtained under the normality assumption. When the assumption is seriously violated, a transformation of data may permit the valid use of the normal theory. We investigate the prediction problem for future values in the original scale when transformations are applied in ARMA models. In this paper, we introduce the methodology based on Yeo-Johnson transformation to solve the problem of skewed data whose modelling is relatively difficult in the analysis of time series. Simulation studies show that the coverage probabilities of proposed intervals are closer to the nominal level than those of usual intervals.

Fabrication and Characterization of an Anodic Aluminum Oxide Template with Variations in the Anodization Solution for pH Sensors

Jo, Ye-Won,Lee, Sung-Gap,Yeo, Jin-Ho,Kim, Kyeong-Min American Scientific Publishers 2016 Journal of Nanoscience and Nanotechnology Vol.16 No.11

<P>In this study, an electrolyte-dielectric-metal (EDM) device incorporating a high-k (high dielectric constant) Al2O3 sensing template from porous anodic aluminum-oxide (AAO) was fabricated through a two-step anodizing process for pH detection. In order to change the morphologies of the AAO template, the anodization solution was varied by controlling the electrolyte. Getting the AAO template having a structure through this experiment was EDM measure the pH sensitivity changes according to the surface area. AAO templates were characterized by X-ray diffraction and field-emission scanning electron microscopy (FE-SEM). The anodic aluminum oxide template for pH sensors went through the following steps: 1st anodizing step at 90 V for 6 h (0.3 M, H3PO4); 2nd anodizing step at 90 V for 1 min (H3PO4 0.3 M); and pore widening for 30 min. The device displayed a good sensitivity of 54.2 mV/pH.</P>

Development of SNP Markers to Distinguish Various Watermelon Traits and Validation Using Fluidigm Genotyping Assay

Sang-Min Yeo(Sang-Min Yeo),Jeong-Eui Hong(Jeong-Eui Hong),Md Abdur Rahim(Md Abdur Rahim ),Saleh Ahmed Shahriar(Saleh Ahmed Shahriar ),Phillip Choe(Phillip Choe),Sun-Kyun Jung(Sun-Kyun Jung),Ill-Sup No 한국육종학회 2023 Plant Breeding and Biotechnology Vol.11 No.2

Watermelon [Citrullus lanatus (Thunb.) Matsum and Nakai] is one of the economically most important fruit crops of the Cucurbitaceae family. Among different watermelon traits, disease resistance and fruit quality are the important traits for growers and consumers. The single nucleotide polymorphism (SNP) markers similar to those traits can potentially and cost-effectively distinguish the genetic variations among these traits. Consequently, we developed 33 SNP makers linked to different watermelon traits associated with fruit quality and disease resistance, and validated in the genetic resources of watermelon and F1 breeding lines using ‘Fluidigm SNP Genotyping’ assay. Most of the SNP markers distinguished the alleles into three different types such as reference allele, alternative allele and heterozygous from watermelon genotypes for various traits. The SNP markers ‘ZymFL-T81P’ (ZYMVresistance), ‘FON1-U161’ and ‘FON1-S075’ (Fusarium wilt-resistance), ‘Pmr21-Cla831’ (PM-resistance), and ‘ClGBS-J168’ and ‘GBS-GC230’ (GSB-resistance) can successfully differentiate resistant (R), susceptible (S) and heterozygous watermelon genotypes. Similarly, the SNP marker associated with sugar content, citrulline content, arginine content, rind hardness, flesh firmness, fruit shape, rind strip pattern of watermelon fruit and seed coat colour can successfully distinguished the watermelon genetic resources and F1 breeding lines as reference allele (A) type, alternative allele (B) type and heterozygous (H). These SNP markers could be utilized for marker assisted selection as well as screening of a large number of watermelon germplasm for fruit quality and disease resistance. However, further validation like artificial inoculation of pathogens for the traits related to disease resistance is required in watermelon crops.

Algorithm for Fault Location Estimation on Transmission Lines using Second-order Difference of a Positive Sequence Current Phasor

Yeo, Sang-Min,Jang, Won-Hyeok,Kim, Chul-Hwan The Korean Institute of Electrical Engineers 2013 Journal of Electrical Engineering & Technology Vol.8 No.3

The accurate estimation of a fault location is desired in distance protection schemes for transmission lines in order to selectively deactivate a faulted line. However, a typical method to estimate a fault location by calculating impedances with voltages and currents at relaying points may have errors due to various factors such as the mutual impedances of lines, fault impedances, or effects of parallel circuits. The proposed algorithm in this paper begins by extracting the fundamental phasor of the positive sequence currents from the three phase currents. The second-order difference of the phasor is then calculated based on the fundamental phasor of positive sequence currents. The traveling times of the waves generated by a fault are derived from the second-order difference of the phasor. Finally, the distance from the relaying point to the fault is estimated using the traveling times. To analyze the performance of the algorithm, a power system with EHV(Extra High Voltage) untransposed double-circuit transmission lines is modeled and simulated under various fault conditions, such as several fault types, fault locations, and fault inception angles. The results of the simulations show that the proposed algorithm has the capability to estimate the fault locations with high speed and accuracy.

Analysis of Transient Overvoltages within a 345kV Korean Thermal Plant

Yeo, Sang-Min,Kim, Chul-Hwan The Korean Institute of Electrical Engineers 2012 Journal of Electrical Engineering & Technology Vol.7 No.3

This paper presents the simulation results for the analysis of a lightning surge, switching transients and very fast transients within a thermal plant. The modeling of gas insulated substations (GIS) makes use of electrical equivalent circuits that are composed of lumped elements and distributed parameter lines. The system model also includes some generators, transformers, and low voltage circuits such as 24V DC rectifiers and control circuits. This paper shows the simulation results, via EMTP (Electro-Magnetic Transients Program), for three overvoltage types, such as transient overvoltages, switching transients, very fast transients and a lightning surge.

Ginsenoside fractions regulate the action of monocytes and their differentiation into dendritic cells

Yeo Jin Lee,Young Min Son,Min Jeong Gu,Ki-Duk Song,Sung-Moo Park,Hyo Jin Song,Jae Sung Kang,Jong Soo Woo,Jee Hyung Jung,Deok-Chun Yang,Seung Hyun Han,Cheol-Heui Yun 고려인삼학회 2015 Journal of Ginseng Research Vol.39 No.1

Background: Panax ginseng (i.e., ginseng) root is extensively used in traditional oriental medicine. It is a modern pharmaceutical reagent for preventing various human diseases such as cancer. Ginsenosidesd-the major active components of ginsengdexhibit immunomodulatory effects. However, the mechanism and function underlying such effects are not fully elucidated, especially in human monocytes and dendritic cells (DCs). Methods: We investigated the immunomodulatory effect of ginsenosides from Panax ginseng root on CD14⁺ monocytes purified from human adult peripheral blood mononuclear cells (PBMCs) and on their differentiation into DCs that affect CD4⁺ T cell activity. Results: After treatment with ginsenoside fractions, monocyte levels of tumor necrosis factor (TNF)-α, interleukin (IL)-6, and IL-10 increased through phosphorylation of extracellular signal-regulated kinase (ERK)1/2 and c-Jun N-terminal kinase (JNK), but not p38 mitogen-activated protein kinase (MAPK). After treatment with ginsenoside fractions, TNF-α production and phosphorylation of ERK1/2 and JNK decreased in lipopolysaccharide (LPS)-sensitized monocytes.We confirmed that DCs derived from CD14⁺ monocytes in the presence of ginsenoside fractions (Gin-DCs) contained decreased levels of the costimulatory molecules CD80 and CD86. The expression of these costimulatory molecules decreased in LPS-treated DCs exposed to ginsenoside fractions, compared to their expression in LPS-treated DCs in the absence of ginsenoside fractions. Furthermore, LPS-treated Gin-DCs could not induce proliferation and interferon gamma (IFN-γ) production by CD4⁺ T cells with the coculture of Gin-DCs with CD4⁺ T cells. Conclusion: These results suggest that ginsenoside fractions from the ginseng root suppress cytokine production and maturation of LPS-treated DCs and downregulate CD4⁺ T cells.

Temperature-dependent Optical Transmittance of Chemically Reduced Graphene Oxide/Hydroxypropyl Cellulose Assembly

Yeo, Min Young,Park, Sung Young,In, Insik The Chemical Society of Japan 2012 Chemistry letters Vol.41 No.2

<P>Stable dispersion of chemically reduced graphene oxide (RGO) is prepared by simple noncovalent interaction with hydroxypropyl cellulose (HPC). Prepared RGO/HPC assembly shows temperature-dependent optical modulation below or above lower critical solution temperature (LCST). Different anchoring modes of HPC chains on RGO plates might contribute to the change of LCST for RGO/HPC assembly at different HPC-to-graphene mass ratio.</P>