• Microbiology and Biotechnology Letters
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• v.16 no.3
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• pp.250-258
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• 1988

Lipases are well known as the enzymes which catalyze the hydrolysis of ester bonds combining aliphatic chains and glycerol on mono-, di- and triglycerides. Their reactions are characterized by be-ing heterogeneous and catalyzing the water-insoluble substrates. This property has been one of the Hurdles which delayed the application of lipases in fats and oils industry, However, with the development of biological reaction system of which organic solvent is introduced in part or whole as the reaction media, enzymatic manipulation of fats and oils is attracting increasing attention from the academic and industrial sectors. Trials in two-phase system and reversed micellar system to produce fatty acids through enzymatic hydrolysis of triglycerides preyed to be efficient in respect to volumetric productivity, fat hydrolysis rate, product separation, etc. In organic solvent system lipases have been found to have the ability to catalyze aminolysis, transesterification, esterification, thiotransesterification and oximolysis that are virtually impossible to catalyze in water. The organic solvent system is being extensively used in interesterifying glycerides to produce a fat with the modified physical and chemical nature.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.46 no.6
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• pp.708-716
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• 2013

Changes in the proximate composition, lipid classes, and fatty acids were studied in chub mackerel Scomber japonicus and Japanese jack mackerel Trachurus japonicus muscles cooked using a frying pan, oven, and microwave oven. The moisture content was high in the raw samples (chub mackerel 65.5%, Japanese jack mackerel 60.5%) and decreased with cooking, especially in the frying pan method (chub mackerel 49.2%, Japanese jack mackerel 49.8%). In contrast, the protein, lipid and ash contents increased significantly with cooking in chub mackerel muscle (P<0.05). However, the lipid content of Japanese jack mackerel muscle showed no significant difference between the samples using the three cooking methods and the raw sample. The dripped lipid contents from the cooked muscles showed the highest levels in the frying pan samples and the lowest levels in the microwave oven samples. The percentage of non-polar lipid (NL) in the total lipid content was over 95% in the muscle lipids (10.43-21.86 g/100 g sample). Prominent fatty acids were 16:0, 18:1n-9, 22:6n-3 (docosahexaenoic acid, DHA), 16:1n-7 and 20:5n-3 (eicosapentaenoic acid, EPA) in both fish muscles and dripped lipids. There was no change in the EPA level in any of the fish muscles, by any cooking method. The percentage of DHA in the muscle of chub mackerel showed the lowest level in the frying pan sample and the highest level in the microwave oven and raw samples, and an intermediate level in the oven sample. However, the percentage of DHA in the Japanese jack mackerel muscle was not significantly different between the various cooking methods. From these results, the microwave oven and oven cooking methods showed relatively low levels of dripped lipid content and loss of n-3 PUFA compared with the frying pan cooking method.

• Journal of Korean Society of Environmental Engineers
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• v.29 no.9
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• pp.989-996
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• 2007

In this study, abiotic transformation of 1-naphthol(1-NP) via oxidative-coupling reaction and its reaction products were investigated in the presence of Mn oxides. The reaction products were characterized for their relative polarity using solvent extraction experiment and reverse-phase HPLC, and for structure using CCMS and LC/MS, and for absorption characteristics using UV-Vis spectrometry. The reaction products present in aqueous phase were more polar than parent naphthol and comprised of 1,4-naphthoquinon(1,4-NPQ) and oligomers such as dimers and trimers. Hydrophilic component present in water phase after solvent$(CH_2Cl_2)$ extractions was identified as naphthol polymerized products having molecular weight(m/z) ranging from 400 to 2,000, and showed similar UV-Vis. absorption characteristics to that of foil fulvic acid. Transformation of 1,4-NPQ, which is non-reactive to Mn oxide, to the polymerized products via cross-coupling reaction in the presence of 1-NP was also verified. In this experimental conditions(20.5 mg/L, 1-NP, 2.5 g/L $MnO_2$, pH 5), the transformation of 1-NP into the oligomers and polymerized products were about 83% of initial 1-NP concentrations, and more than 30% of the reaction products was estimated to be water insoluble fractions, not extracted by $H_2O$ methanol. Results from this study suggest that Mn oxide-mediated treatment of naphthol contaminated soils can achieve risk reduction through the formation of oligomers md polymer precipitation.

• Ocean and Polar Research
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• v.41 no.4
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• pp.311-318
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• 2019

We analyzed the preliminary survey data (2014-2016) of macrobenthic community biomass (n = 112) from the wind farm area located in the southern part of the west coast of Korea and compared this data with data from the entire west coast (n = 369; 2006-2008). Modal classes from frequency distributions were 6 times higher in the latter (5 vs. 32 g/㎡). The mean and median values of the latter were 1.3 and 1.7 times higher (mean, 20.7 vs. 27.8 g/㎡; median, 17.1 vs. 29.5 g/㎡), and the maximum value was 3.4 times higher. Mood's median test showed significant difference at p-value = 0.01. We estimated the biomass-to-depth relationships from each data set by using Akaike Information Criterion and regarded the non-overlap of the 95% confidence intervals as indicating significant difference. The biomass was different from a 10 m depth below, and 3 times higher in the west coast at around 20 m compared with the maximum depth of the wind farm area. A local event of catastrophic sedimentation ranging from 1 to 2 m was observed in the wind farm during winter surveys. This could be a probable source of the lower biomass, but information on biomass seasonality and a natural experimental approach seem to be needed for the conduct of further studies. This study is meaningful in that it provided the background to assess future changes by understanding the lower level of benthic productivity in the area. We expect this study will contribute to the preparation of measures that can remove or mitigate the source of the lower biomass and improve the productivity of fishery resources in the area.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.45 no.4
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• pp.317-327
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• 2012

The changes in the proximate compositions, lipid classes, and fatty acids of muscle and dripped lipids, and the amino acid compositions and mineral content were studied in Spanish mackerel Scomberomorus niphonius muscle cooked using a frying pan, oven, and microwave oven. The moisture content was high in the raw sample (65.7%) and decreased with cooking, decreasing the most with frying pan method (54.5%). Conversely, the protein, lipid and ash contents increased significantly with cooking (P<0.05). The dripped lipid content from the cooked muscles was the highest with the frying pan sample (0.81%) and was approximately half this level in the oven (0.46%) and microwave oven (0.34%) samples. The percentage of non-polar lipid (NL) in the total lipid content exceeded 95% for the muscle lipids (13.9-17.6 g/100 g sample) and 99% for the dripped lipids (0.34-0.81 g/100 g sample). The prominent fatty acids were 18:1n-9, 16:0, 22:6n-3, 16:1n-7, and 20:5n-3 in the muscle and dripped lipids. The frying pan muscle lipid contained high levels of saturates and monoenes such as 16:0, 18:0, and 18:1n-9, and low levels of polyenes compared with other muscle lipids. The fatty acid compositions of the dripped lipids were similar with all three cooking methods. The prominent total amino acids in Spanish mackerel muscle were glutamic acid, aspartic acid, lysine, leucine, and arginine, and their proportions were similar (45.49-45.82%) in all samples. The potassium and phosphorous contents increased significantly with cooking (P<0.05), and while no heavy metals were detected in any sample. These results indicate that the change in nutritional components, especially the lipid content, was lower with the microwave oven and oven methods compared with the frying pan method.

• Clinical and Experimental Pediatrics
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• v.51 no.11
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• pp.1232-1235
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• 2008

Imipramine, a tricyclic antidepressant (TCA), is used for the treatment of non-polar depression and nocturnal enuresis in children in whom an organic pathology has been excluded, anxiety disorders, and neuropathic pain. Clinical toxicity following the treatment of TCAs, including imipramine, is well known. The anticholinergic effects initially present include a dry mouth, ileus, dilated pupils, urinary retention, and mild sinus tachycardia. The central nervous system toxicity includes delirium, agitation, restlessness, hallucinations, convulsions, and CNS depression or coma. However, the most life-threatening toxicity remains the development of cardiac dysrhythmias. Conduction delays such as QRS and corrected QT prolongation, wide QRS complex tachycardia, and the Brugada electrocardiographic pattern have been reported. Sodium bicarbonate decreases QRS widening and suppresses dysrhythmias by providing excess sodium to reverse the TCA-induced sodium-channel blockade and possibly by binding directly to the myocardium. There are no pediatric case reports on imipramine or other TCA associated toxicity in Korea. Here, we describe a patient who presented with convulsions, tachycardia with a wide QRS complex, a Brugada electrocardiographic pattern, and anuresis associated with an accidental overdose of imipramine and the outcome of treatment with sodium bicarbonate.

• Korean Journal of Food Science and Technology
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• v.13 no.1
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• pp.30-36
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• 1981

Neutral lipids of the total lipid extracted from 4 representative varieties of barley grown in Korea and their corresponding malt were studied. Total lipids of barley and malt were solvent extracted with chloroform:methanol:water (1.0 : 1.0 : 0.9, v/v), The total lipids were fractionated into neutral and polar lipids by silicic acid column chromatography, and neutral lipids fraction was separated by thin layer chromatography and quantitated by TLC scanner. The fatty acid compositions was determined by gas liquid chromatography. The average content of total lipid in the 4 barleys and their malts were 3.3 and 2.9%, and average of neutral lipids content in the barley and malt lipids were 73.8 and 68.5%, respectively. Among the neutral lipids, triglycerides and free fatty acids were the major components, and triglycerides content decreased and free fatty acids content increased during malting. Sterol esters, free sterols, 1,3-and 1,2-diglycerides were the minor components of the neutral lipids, and contents of those components showed increasing tendency during malting. The major fatty acid composition of the total lipids were linoleic, palmitic and oleic acids, and in general, the malts had lower amounts of unsautrated fatty acids and high amounts of saturated fatty acids. Fatty acid composition of neutral lipids was of almost the same pattern as that of the total lipids.

• Proceedings of the Korean Vacuum Society Conference
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• 2012.02a
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• pp.358-359
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• 2012

최근 분극 특성이 상이한 무분극 GaN 에피성장에 관한 심도 있는 연구와 함께 전자-전공 캐리어의 주입 및 캐리어의 거동, 방출되는 편광 특성 및 다양한 물리적 특성들에 대해 보고되고 있으며, 광학적 특성 및 물리적 특성의 확보를 위한 많은 연구가 활발히 진행 중이다 [1]. GaN의 ohmic 접촉(ohmic contact)의 형성은 발광 다이오드(light emitting diode), 레이저 다이오드(Laser), 태양전지(solar cell)와 같은 고신뢰도, 고효율 광전자 소자를 제조하기 위해서는 매우 중요하다 [2]. 그러나 이와 함께 병행 되어야 할 무분극 p-GaN 의 ohmic contact에 관한 연구는 많이 이루어지고 있지 않는 실정이다. 따라서 본 논문에서는 r-plane 사파이어 기판 상에 성장된 p-GaN에서의 ohmic 접촉 형성 연구를 위하여 Ni/Au ohmic 전극의 접촉저항 특성을 연구하였다. 본 실험에서는 성장된 a-plane GaN의 Hole농도가 $3.09{\times}1017cm3$ 인 시편을 사용하였다. E-beam evaporation 장비를 이용하여 Ni/Au를 각각 20 nm 그리고80 nm 증착 하였으며 비접촉저항을 측정하기 위해 Circle-Transfer Length Method (C-TLM) 패턴을 사용하였다. 샘플은 RTA (Rapid Thermal Annealing)를 사용하여 $300^{\circ}C$에서 $700^{\circ}C$까지 온도를 변화시키며 전기적 특성을 비교하여 그림 1(a) 나타내었다. 그림에서 알 수 있듯이 $400^{\circ}C$에서 가장 낮은 비접촉저항 값인 $6.95{\times}10-3{\Omega}cm2$를 얻을 수 있음을 발견하였다. 이 때의 I-V curve 도 그림1(b)에 나타낸 바와 같이 열처리에 의해 크게 향상됨을 알 수 있다. 그러나, $500^{\circ}C$ 이상 온도를 증가시키면 다시 비접촉 저항이 증가하는 것을 관찰하였다. XRD (x-Ray Diffraction) 분석을 통하여 $400^{\circ}C$ 이상열처리 온도가 증가하면 금속 표면에 $NiO_2$가 형성되며, 이에 따라 오믹특성이 저하 된다고 사료된다. 또한 $Ni_3N$의 존재를 확인 하였으며 이는 nonpolar surface의 특성으로 인해 nitrogen out diffusion 현상이 동시에 발생하여 계면에는 dopant로 작용하는 질소 공공을 남기고 표면에 $Ni_3N$을 형성하여 ohmic contact의 특성이 저하되기 때문인 것으로 사료된다.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.48 no.4
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• pp.415-427
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• 2012

Seasonal variation in species composition and abundance of fish assemblage in the north coast (NC: Ayajin) and central coast (CC: Hupo) of the East Sea were calculated using samples collected by trammel net during 2011-2012. A total of 20 species from NC and 17 species from CC were collected. Of the fishes collected, the dominant fish species were Glyptocephalus stelleri and Careproctus rastrinus in the NC, and Dasycottus setiger and G. stelleri in the CC. These 2 fishes accounted for 71.7% and 81.0% of the total number of individuals collected in the NC and CC, respectively. The number of fish species, number of individuals, biomass and species diversity indices fluctuated with the seasons. The cluster analysis and non-metric multidimensional scaling (MDS) based on Bray-Curtis similarity revealed that the fish assemblages classified into north and central groups. Analysis of similarity percentages of species contributions (SIMPER) indicated that most individual of G. stelleri and Gadus macrocephalus contributed to north group, and D. setiger and G. stelleri in central group, whereas 15 species contributed to 90% of the dissimilarity.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.39 no.5
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• pp.367-375
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• 2006

The chemical components, lipid class, and fatty acid composition of muscle from male and female common squid, Todarodes pacificus, were examined to evaluate the potential utilization of muscle from fin, head, arms, and tentacles, which consumers usually like less than the mantle. The mantle was found to constitute 47-49% of the total muscle and the proportion was slightly higher in females than in males. For the remaining 51-53% of the muscle, the only gender difference was that the arms of males contained approximately 3% more muscle than those of females (P<0.05). The protein content was higher in the mantle, arms, and tentacles than in the fin and head in both males and females (P<0.05), and was slightly higher in males (15.7-20.7%) than in females (15.1-19.2%). By contrast, the lipid content was slightly higher in females (1.82-2.54%) than in males (1.01-2.37%), and the fins in both males and females contained the most lipids (2.37-2.54%) of all muscle. The prominent lipid classes in the muscles were free sterol (males 81.5-91.9% vs. females 84.9-91.8% for the non-polar lipid content), phosphatidylcholine (PC, males 59.3-62.4% vs. females 49.2-57.8% for the phospholipid content) and phosphatidylethanolamine (PE, males 22.0-28.8% vs. females 25.6-33.8% for the phospholipid content). The percentage of PC was approximately 5-10% higher in males (P<0.05), especially in the fin, while that of PE was approximately 3-5% higher in female (P<0.05), especially in the head. All of the squid muscle contained 52.1-54.9% of n-3 polyunsaturated fatty acids (PUFA), such as docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA). Males contained slightly more DHA, whereas female contained more EPA. The total percentage of n-3 PUFA differed little among muscles within the same gender.