선박 전기전자기기용 서지방호장치의 제작

장운용(Un-Yong Jang),정광석(Kwang-Seok Jung),박대원(Dae-Won Park),길경석(Gyung-Suk Kil),박성주(Sung-Ju Park) 한국마린엔지니어링학회 2010 한국마린엔지니어링학회 학술대회 논문집 Vol.2010 No.10

This paper presented surge protective method and devices for shipboard electrical and electronics devices. Parallel type surge protective devices (SPD) for the 440 [V] and a series type SPD for the 220 [V] rated voltage were designed and fabricated. The performance were evaluated by an un-powered test which applies the 8/20 [㎲] surge current Lip to 10 [㎄]. The maximum clamping voltage of the parallel and the series type SPD were 1,032 [V] and 875 [V], respectively.

Physico-chemical Characteristics of Ammonia Adsorbed Fly Ash (AAFA)

Kim, Jae-kwan,Park, Seok-un,Hong, Jin-pyo Korea Electric Power Corporation 2018 KEPCO Journal on electric power and energy Vol.4 No.1

Ammonia Adsorbed Fly Ash (AAFA) samples produced from coal fired plants equipped with SNCR (Selective Non-Catalytic Reduction) of nitrogen oxides with urea have been chemically analyzed, and their physical and dissolution properties have been investigated. XRD results for the ammonia component in AAFA ascertained that ABS (ammonium bisulfate) and AS (ammonium sulfate) were deposited on fly ash as $SO_3$ reacted with unreacted ammonia at SNCR. SEM and EDS images showed that fine ashes on large fly ash surface of sphere type were agglomerated, due to adhesive role of ammonium salts attached fly ashes. Dissolution test results of ammonium salts absorbed on AAFA in distilled water or sea water showed that the proportion of un-ionized $NH_3$ to $NH_4{^+}$ were primarily a function of pH and temperature. Increasing pH and temperature causes an increase in the fraction of un-ionized $NH_3$. At pHs of 9.6 and 10.7, un-ionized $NH_3$ and $NH_4{^+}$ ions are present in equal amounts at distilled water and sea water, respectively.

Effect of C/N Ratio and Diffuser Position for the SNR of Advanced Treatment Process in Industrial Wastewater

Seok-Hwan PARK,Yong-Un KIM,Eun-Tae LIM,Don-Hee PARK 한국생물공학회 2011 한국생물공학회 학술대회 Vol.2011 No.4

Functional Screening of Plant Genes Suppressed Salt Sensitive Phenotype of Calcineurin Deficient Mutant through Yeast Complementation Analysis

Seok-Jun Moon(문석준),Soo-Kwon Park(박수권),Un-Ha Hwang(황운하),Jong-Hee Lee(이종희),Sang-Ik Han(한상익),Min-Hee Nam(남민희),Dong-Soo Park(박동수),Dongjin Shin(신동진) 한국생명과학회 2013 생명과학회지 Vol.23 No.1

작물의 생산성 증가를 위해 염해 저항성 메커니즘을 이해하는 것이 중요하다. 식물의 염해 저항성에 관련된 유전자를 확보하기 위한 여러 가지의 선별방법이 개발되었다. 본 논문에서는 애기장대의 cDNA 라이브리를 염해 감수성 효모인 cnb 돌연변이체에 삽입하여 염해 감수성 표현형을 회복하는 콜로니를 선발하였다. 이 선별방법을 통하여 34종의 cnb 돌연변이체의 염해 감수성을 회복하는 콜로니를 선별하였으며, 염기서열분석을 통하여 CaS와 AtSUMO1, AtHB-12 등 9종의 유전자임을 확인하였다. 이들 유전자 중 CaS의 발현이 염해 저항성을 증가시키는 것과 염해 처리에 의해 CaS의 유전자의 발현이 증가되는 것을 확인하였다. CaS 발현억제 형질전환체는 100 mM 염처리에 의하여 뿌리생장이 저해되었다. 또한 150 mM 염처리에 의하여 CaS 발현억제 형질전환체의 잎에서 백화현상을 나타내었다. 이러한 결과를 통하여 CaS 유전자가 효모와 식물에서 염해 저항성에 중요한 유전자임을 증명하였다. Understanding salt tolerance mechanisms is important for the increase of crop yields, and so, several screening approaches were developed to identify plant genes which are involved in salt tolerance of plants. Here, we transformed the Arabidopsis cDNA library into a salt-sensitive calcineurin (CaN)-deficient (cnbΔ) yeast mutant and isolated the colonies which can suppress salt-sensitive phenotype of cnbΔ mutant. Through this functional complementation screen, a total of 34 colonies functionally suppressed the salt-sensitive phenotype of cnbΔ yeast cells, and sequencing analysis revealed that these are 9 genes, including CaS, AtSUMO1and AtHB-12. Among these genes, the ectopic expression of CaSgene increased salt tolerance in yeast, and CaStranscript was up-regulated under high salinity conditions. CaS-antisense transgenic plants showed reduced root elongation under 100 mM NaCl treatment compared to the wild type plant, which survived under 150 mM NaCl treatment, whereas CaS-antisense transgenic plant leaves turned yellow under 150 mM NaCl treatment. These results indicate that the expression of CaS gene is important for stress tolerance in yeast and plants.

Review on Evaluation of Rare Earth Metals and Rare Valuable Metals Contained in Coal Ash of Coal-fired Power Plants in Korea

Park, Seok-Un,Kim, Jae-Kwan,Seo, Yeon-Seok,Hong, Jun-Seok,Lee, Hyoung-Beom,Lee, Hyun-Dong Korea Electric Power Corporation 2015 KEPCO Journal on electric power and energy Vol.1 No.1

Distribution of rare earth metals (REMs) and rare valuable metals (RVMs) contents in coal ashes (fly ash, bottom ash, and pond ash) and leachate from 11 coal-fired power plants in Korea were investigated. Coal ashes and leachates were found to contain important REMs and RVMs such as Yttrium (Y) and Neodymium (Nd), which was in the range of 23~75 mg/kg. However, it still requires developing effective recovery and separation methods in order to utilize REMs and RVMs in ash and leachate. Recovery of valuable elements (Y and Nd) from various and extensive ash sources (8.21 million tons/year in 2013) can provide the existing power plants with additional profit; therefore, it can significantly improve economics of the power plants.

Hematological Aspects in A Endotoxemic Young Rabbit Model

Park, Seok-Cheol,Kwon, Heun-Young,Kim, Jai-Young,Hwang, Soo-Myung,Kim, Tae-Un,Seong, Hee-Kyung,Kim, Yang-Weon,Lee, Won-Jae 대한의생명과학회 2002 Journal of biomedical laboratory sciences Vol.8 No.3

Gram-negative septicemia, which continues to be a serious clinical problem, is one of the major causes of morbidity and mortality in hospitalized patients. Endotoxin of gram-negative bacteria is a pivotal pathogen of sepsis. To understand the effect of endotoxin on hematological aspect and the time course in early childhood, this study was designed with experimental septic model of young rabbits (8 week-old). Rabbits were divided into control (n=7) and endotoxin group (0.50 mg/kg of endotoxin). The endotoxin group was subdivided into six groups by the sampling times: 3, 6, 12, 24, 48 and 72 hr-group (E-G$_{3}$, E-G$_{6}$, E-G$_{12}$, E-G$_{24}$, E-G$_{48}$ and E-G$_{72hrs}$, each n=7). The evaluation of CBC, activated partial thromboplastin time (APTT), prothrombin time (PT), fibrinogen concentration, coagulation factors and D-dimer were taken from the bloods. The number of leukocytes was lower in E-G$_{3}$ and E-G$_{6hrs}$ (due to pantocytopenia), whereas it was higher in E-G$_{24}$ and E-G$_{48}$ (due to neutrophilia and/or lymphophilia) than in control group (P<0.05). Platelet counts in E-G$_{3}$, E-G$_{6}$, E-G$_{12}$, E-G$_{24}$ and E-G$_{48hrs}$ were lower than those of control group (P<0.05). Normoblast counts in E-G$_{3}$, E-G$_{6}$, E-G$_{12}$, E-G$_{24}$ and E-G$_{48hrs}$ were higher than those of control group (p<0.01). APTT in E-G$_{3}$, E-G$_{6}$, E-G$_{12}$, E-G$_{24}$ and E-G$_{72hrs}$ were longer while PT in E-G$_{3}$, E-G$_{6}$, E-G$_{48}$ and E-G$_{72hrs}$ were higher than those of control group (p<0.05). Fibrinogen concentrations were lower in E-G$_{3}$, E-G$_{6}$ and E-G$_{12}$ but higher in E-G$_{48}$ and E-G$_{72hrs}$ than those of control (p<0.05). Intrinsic coagulation factors (XII, XI, IX, VIII) in all endotoxin groups were significantly lower than those of control group (p<0.05). Extrinsic coagulation factor (X, VII, V, II) were lower in E-G$_{3}$, E-G$_{6}$, E-G$_{12}$ and E-G$_{24hrs}$ whereas they were higher in E-G$_{48}$ and E-G$_{72hrs}$ than in control group (p<0.05). D-dimer concentrations in E-G$_{48}$ and E-G$_{72hrs}$ were higher than those of control group (P<0.001). We concluded that endotoxin led to extensive hematological disturbances including disseminated intravascular coagulation in the young rabbits and that this pathologic condition in the infant and childhood groups will cause the grave results.

Influence of light-emitting diodes on phenylpropanoid biosynthetic gene expression and phenylpropanoid accumulation in Agastache rugosa

Park Woo Tae,Yeo Sun Kyung,Sathasivam Ramaraj,Park Jong Seok,Kim Jae Kwang,Park Sang Un 한국응용생명화학회 2020 Applied Biological Chemistry (Appl Biol Chem) Vol.63 No.3

Agsatache rugosa (Korean mint), belongs to the mint family and it has various medicinal properties. In addition, it has several valuable compounds such as monoterpenes and phenylpropanoid compounds. Amongst these, two compounds viz., rosmarinic acid (RA), and tilianin are well-known natural compounds that have numerous pharmacological properties. The phenylpropanoid biosynthetic gene expression under stress conditions and the subsequent accumulation of phenylpropanoid content has not been extensively studied in Korean mint. Here, we investigated the effect of light-emitting diodes (LEDs) on the expression levels of phenylpropanoid biosynthetic pathway genes and the accumulation of phenylpropanoid compounds such as RA and tilianin in A. rugosa. Real-time PCR analysis showed that the phenylpropanoid pathway genes responded to the LED lights. The transcript levels of downstream genes (C4H, CHS, CHI, and RAS) were comparatively higher than those of upstream genes (PAL, TAT , and HPPR). In addition, HPLC analysis showed that the content of RA and tilianin were significantly higher in plants cultivated under white light than those grown under red, blue, green, and orange lights. The RA and tilianin content were the highest in the plantlets after three weeks of exposure to white light. These results suggested that white LED lights significantly enhanced the accumulation of phenylpropanoid compounds in A. rugosa.

Directed evolution of the 3-hydroxypropionic acid production pathway by engineering aldehyde dehydrogenase using a synthetic selection device

Seok, Joo Yeon,Yang, Jina,Choi, Sang Jin,Lim, Hyun Gyu,Choi, Un Jong,Kim, Kyung-Jin,Park, Sunghoon,Yoo, Tae Hyeon,Jung, Gyoo Yeol Elsevier 2018 Metabolic engineering Vol.47 No.-

<P><B>Abstract</B></P> <P>3-Hydroxypropionic acid (3-HP) is an important platform chemical, and biological production of 3-HP from glycerol as a carbon source using glycerol dehydratase (GDHt) and aldehyde dehydrogenase (ALDH) has been revealed to be effective because it involves a relatively simple metabolic pathway and exhibits higher yield and productivity than other biosynthetic pathways. Despite the successful attempts of 3-HP production from glycerol, the biological process suffers from problems arising from low activity and inactivation of the two enzymes. To apply the directed evolutionary approach to engineer the 3-HP production system, we constructed a synthetic selection device using a 3-HP-responsive transcription factor and developed a selection approach for screening 3-HP-producing microorganisms. The method was applied to an ALDH library, specifically aldehyde-binding site library of alpha-ketoglutaric semialdehyde dehydrogenase (KGSADH). Only two serial cultures resulted in enrichment of strains showing increased 3-HP production, and an isolated KGSADH variant enzyme exhibited a 2.79-fold higher catalytic efficiency toward its aldehyde substrate than the wild-type one. This approach will provide the simple and efficient tool to engineer the pathway enzymes in metabolic engineering.</P> <P><B>Highlights</B></P> <P> <UL> <LI> A synthetic selection device was designed responding to 3-HP concentration. </LI> <LI> ALDH in the 3-HP pathway was engineered through a simple selection method. </LI> <LI> An ALDH variant exhibited a 2.79-fold improvement in the catalytic efficiency. </LI> <LI> <I>E. coli</I> with ALDH variant showed a 25% higher productivity than the parental strain. </LI> <LI> The developed strategy was highly efficient for engineering the pathway enzymes. </LI> </UL> </P>

Functional Disconnectivity in Individuals with Major Depressive Disorder: Resting State fMRI Study

( Un Jung Jang ),( Ji Woo Seok ),( Mi Sook Park ),( Young Ji Eum ),( Jin Hun Sohn ) 한국감성과학회 2015 추계학술대회 Vol.2015 No.-

An inability to self-regulate negative emotions appears to play a pivotal role in the genesis of major depressive disorder(MDD). Brain imaging studies have reported that the prefrontal cortex(PFC) and the anterior cingulated cortex(ACC) is the key structures for mood regulation. In task-based studies, MDD group has shown the altered functional connectivity in the PFC-the dACC during emotional processing compared to control group. The goal of the study was to examine the difference of functional connectivity in resting state between MDD group and control group. Nine MDD participants(mean age: 21 ± 2.47) and 9 healthy controls(mean age: 23 ± 1.80) participated in the experiment. For the connectivity analysis, the MPFC was defined as a seed region based on the previous studies. Correlation coefficient images between the MPFC and some brain areas of gray matter were z-transformed. And then t-tests were performed to exam differences of group connectivity. There was significant group difference in BDI score(MDD group: 26 ± 7.17, Control group: 4 ± 3.64). The MPFC was positively correlated with the superior frontal gyrus(SFC), the dorsal anterior cingulate gyrus(dACC), and the insular cortex(IC) both in the control and the patient group. It was found that the connectivity between the MPFC and the dACC(BA32) was stronger in MDD group than in healthy controls. We found the abnormality of functional connectivity between the PFC and the ACC even during the resting state in MDD participants. It can be concluded that there are abnormality of functional connectivity both in resting state and cue-induced activation in MDD group. This result might imply altered connectivity between these two regions could be a neurobiological indicator of MDD.

Effects of Proinflammatory Cytokines and Natural Products on Mucin Release from Cultured Hamster Tracheal Surface Epithelial Cells

Park, Ji-Sun,Kim, Hyoung-Soo,Seok, Jeong-Ho,Hur, Gang-Min,Park, Jong-Sun,Seo, Un-Kyo,Lee, Choong-Jae The Korean Society of Pharmacology 2004 The Korean Journal of Physiology & Pharmacology Vol.8 No.6

In this study, we investigated whether TNF-alpha, IL-1beta, CTMA (carboxymethyl trimethylammonium) and LPD (Lup-20[29]-ene-3beta,28-diol) affect mucin release from airway goblet cells and compared the activities of these agents with the inhibitory action of PLL and the stimulatory action of ATP on mucin release. Confluent primary hamster tracheal surface epithelial (HTSE) cells were metabolically radiolabeled with $^3H-glucosamine$ for 24 h and chased for 30 min in the presence of varying concentrations of each agent to assess the effects on $^3H-mucin$ release. The results were as follows: TNF-alpha, CTMA and LPD increased mucin release at the highest concentration, but IL-1beta did not. We conclude that CTMA and LPD can stimulate mucin release by directly acting on airway mucin-secreting cells, and suggest that these agents should be further investigated for the possible use as mild expectorants during the treatment of chronic airway diseases.