• Applied Chemistry for Engineering
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• v.25 no.3
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• pp.254-261
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• 2014

The transformer is a static electrical device that transfers energy by inductive coupling. Then, heat is occurred at coils, inner transformer was filled with insulating oils for cooling and insulation. Although mineral oil as insulating oil has been widely used, it does not meet health and current environmental laws because it is not biodegradable. Therefore, in this study, the diglycerol ester was synthesized with diglycerol and fatty acids (oleic acid and caprylic acid) over various catalysts for insulating oil having biodegradability, high flash points and low pour points. The sulfated zirconia ($SO_4{^{2-}}/ZrO_2$) catalyst prepared at different calcination temperature shows the highest conversion of fatty acids at $600^{\circ}C$ due to crystallinity and high density of acid sites per surface area. When the molar ratio of oleic acid and caprylic acid is 1:3, the diglycerol ester shows superior insulation properties that are the flash point of $306^{\circ}C$ and pour point of $-50^{\circ}C$. The insulation properties of synthesized diglycerol ester shows the pour point of $-50^{\circ}C$ and the flash point of over $300^{\circ}C$. Therefore, diglycerol ester is superior to the vegetable oils in insulation properties.

• Analyses & Alternatives
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• v.6 no.2
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• pp.155-183
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• 2022

The purpose of this study is to econometrically analyze the negative impact of the May 18 Democratic Uprising on the Gwangju/Jeonnam regionional economy using the Synthetic Control Method (SCM). The SCM SCM is a methodology similar to the difference-in-difference(DID) method of microeconometrics. It is applied to macroeconomic variables such as country, region, etc. to estimate the causal relationship between specific events and the dependent variable. In this study, as of 1980, local tax revenue data of metropolitan local governments were used as a proxy variable for the economy of the region, and the impact of the May 18 Democratic Uprising on the economy of Gwangju/Jeonnam region was analyzed through various socio-economic indicators. In this study, data were used to analyze from 1971 to 2000, and as a result of empirical analysis, local tax revenues in Gwangju/Jeonnam area were less collected than normal routes up to 17%. In addition, the significance of this analysis was confirmed through in-time placebo effect analysis and in-space placebo effect analysis, which are methods of analyzing the robustness of the control group synthesis method.

• Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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• 2003.10a
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• pp.205.1-205
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• 2003

본 연구는 국내 유통쌀의 포장재로 널리 이용되고 있는 지대포장재와 합성수지계열의 PE 및 AL 포장재의 저장기간에 따른 품질특성을 구명하고, 포장재의 투습도 5~700g/$m^2$범위의 4수준에 대하여 함수율, 중량 및 지방산가의 변화를 측정하여 포장재의 적정 투습도를 결정하는데 목적이 있다. 지대, PE 및 AL포장재의 저장 4주 후의 중량은 7.8, 0.1 및 1.5%감소하였으며, 함수율은 지대포장의 경우 3.7%(w.b.)감소하였다. 지방산가는 저장 4주 후에 지대포장은 9.4, PE포장재는 42.0, AL포장재는 16.8(mg KOH/100g)로 나타났다. 저장온도 20 및 3$0^{\circ}C$에서의 포장재 투습도에 따른 중량, 함수율 및 지방산가의 변화를 고려했을 때 130~210g/$m^2$이 적정한 것으로 나타났다.

• 건강소식
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• v.34 no.7
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• pp.28-29
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• 2010

산나물은 우리 몸이 요구하는 필요 영양분을 다양하고 풍부하게 갖췄다. 비타민C와 무기질, 단백질과 지방은 물론 체내에서 합성되지 않는 필수 아미노산의 조성도 우수하다. 섬유질은 비만과 당뇨병에 유효할 뿐만 아니라 심장병과 암, 비만 등의 치유에 효험을 나타낸다. 또한 콜레스테롤의 조절과 숙변제거 등에도 유익한 구실을 한다. 우리 몸에 유익한 대표적인 산나물인 산마늘에 대해 알아본다.

• Korean Journal of Plant Resources
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• v.28 no.5
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• pp.582-590
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• 2015

In the present study, we investigated the effect of 70% EtOH extract from Hippophae Rhamnoides L. leaves (HRL) on the anti-obesity effect in 3T3-L1 cells. The effects of HRL on lipid accumulation in 3T3-L1 cells were examined using Oil Red O staining. In addition, we examined the gene expression levels by using RT-PCR and western blot. The results of this analysis showed that 100 ㎍/㎖ HRL significantly increased the inhibition of lipid accumulation by 82.25%; significantly decreased the mRNA expression of sterol regulatory element binding protein-1c (SREBP-1c), peroxisome proliferator-activated receptor γ (PPARγ), CCAAT/enhancer binding proteins α (C/EBPα), and fatty acid synthase (FAS) in 3T3-L1 cells as well as the stimulated protein expression of AMP-activated protein kinase (AMPK); and suppressed the expression level of PPARγ. These results suggest that HRL can prevent adipogenesis through activation of AMPKα and inhibition of adipogenesis transcription factors.

• Korean Journal of Poultry Science
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• v.43 no.1
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• pp.47-54
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• 2016

The aim of this study was to investigate the expression patterns of key genes involved in lipid metabolism in response to dietary Coenzyme Q10 (CoQ10) in hens. A total of 36 forty week-old Lohmann Brown were randomly allocated into 3 groups consisting of 4 replicates of 3 birds. Laying hens were subjected to one of following treatments: Control (BD, basal diet), T1 (BD+ CoQ10 100 mg/kg diet) and T2 (BD+ micellar of CoQ10 100 mg/kg diet). Birds were fed ad libitum a basal diet or the basal diet supplemented with CoQ10 for 5 weeks. Total RNA was extracted from the liver for quantitative RT-PCR. The mRNA levels of HMG-CoA reductase(HMGCR) and sterol regulatory element-binding proteins(SREBP)2 were decreased more than 30~50% in the liver of birds fed a basal diet supplemented with CoQ10 (p<0.05). These findings suggest that dietary CoQ10 can reduce cholesterol levels by the suppression of the hepatic HMGCR and SREBP2 genes. The gene expressions of liver X receptor (LXR) and SREBP1 were down regulated due to the addition of CoQ10 to the feed (p<0.05). The homeostasis of cholesterol can be regulated by LXR and SREBP1 in cholesterol-low-conditions. The supplement of CoQ10 caused a decreased expression of lipid metabolism-related genes including $PPAR{\gamma}$, XBP1, FASN, and GLUTs in the liver of birds (p<0.05). These data suggest that CoQ10 might be used as a dietary supplement to reduce cholesterol levels and to regulate lipid homeostasis in laying hens.

• Journal of Korean Society of Transportation
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• v.19 no.6
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• pp.171-182
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• 2001

Travel Time is an important characteristic of traffic conditions in a road network. Currently, there are so many road users to get a unsatisfactory traffic information that is provided by existing collection systems such as, Detector, Probe car, CCTV and Anecdotal Report. This paper presents the results achieved with Data Fusion Model, Hybrid Neuro Fuzzy System for on - line estimation of travel times using RTMS(Remote Traffic Microwave Sensor) and Probe Data in the signalized arterial road. Data Fusion is the most important process to compose the various of data which can present real value for traffic situation and is also the one of the major process part in the TIC(Traffic Information Center) for analyzing and processing data. On-line travel time estimation methods(FALEM) on the basis of detector data has been evaluated by real value under KangNam Test Area.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.23 no.1
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• pp.149-157
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• 2010

목적 : 월견초는 다량의 불포화 지방산인 리놀렌산과 감마 리놀렌산을 함유하고 있으며, 천식성 기침이나 아토피피부염에 효능이 있는 것으로 알려져 있다. 본 연구는 월견초의 전초와 종자 추출물의 피부 멜라닌 합성에 대한 억제 효과를 조사하였다. 방법 : B16F10 멜라닌세포주를 이용하여 멜라닌, tyrosinase 활성 및 세포생존율을 측정하였다. 또한 멜라닌 합성- 관련효소인 tyrosinase, TRP-1, TRP-2의 단백질발현과 $\alpha$-MSH를 처리하여 색소침착을 유도 한 뒤 단백질 발현을 조사하였다. 결과 : 월견자는 B16F10 세포의 멜라닌 합성을 $5\;{\mu}g/ml$와 $10\;{\mu}g/ml$ 농도에서 각각 대조군의 81.3%, 68.3%로 억제하였고 tyrosinase의 활성도 이와 유사하게 억제하였다. 멜라닌 합성-관련효소들의 단백질발현을 관찰한 결과 월견초와 월견자는 tyrosinase 발현을 억제하였으며 TRP-1과 TRP-2의 발현에는 영향을 주지 않았다. 특히 $\alpha$-MSH에 의한 과색소 유도 시 tyrosinase 발현이 현저하게 감소되었으며, 월견자의 멜라닌 합성 억제 효과가 월견초 보다 높게 나타났다. 결론 : 이상의 연구 결과 월견자는 멜라닌세포의 tyrosinase 단백질 발현과 tyrosinase 활성을 억제하여 멜라닌 생성을 감소시키는 것으로 사료된다.

• Journal of Life Science
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• v.32 no.12
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• pp.962-970
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• 2022

Nonalcoholic steatohepatitis (NASH) is the progressive stage of nonalcoholic fatty liver disease (NAFLD) that highly increases the risk of cirrhosis and liver cancer, and there are few therapeutic options available in the clinic. Poricoic acid (PoA), a component of Poria cocos Wolf, has a wide range of pharmacological activities; however, little is known about its effects on NASH. The preventive effects of PoA on NASH were examined in vivo and in vitro by analyzing triglyceride synthesis, inflammation and fibrosis. In the high fat and methionine-choline deficient diet (HFMCD)-induced NASH mice, PoA reduced the liver weight and the levels of alanine aminotransferase and aspartate aminotransferase compared with non-treated HFMCD group. The staining with Oil Red O and hematoxylin and eosin revealed that PoA administration reduced red staining and the size of lipid droplet. qPCR analysis showed that PoA also reduced the expression of genes related to triglyceride synthesis. Further, immunostaining with CD68 and qPCR analysis revealed that PoA reduced the staining with CD68 and the expression of inflammatory genes induced by HFMCD. Moreover, PoA reduced the staining with sirius red and antibody of α-smooth muscle actin and also reduced the expression of genes related to fibrosis. The treatment of PoA to AML12 cells reduced the increase in triglyceride amount and expression of genes associated with triglyceride synthesis, inflammation and fibrosis. Taken together, our study indicate that PoA has therapeutic effect on NASH through preventing triglyceride synthesis, inflammation and fibrosis.

• Tribology and Lubricants
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• v.1 no.1
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• pp.80-87
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• 1985

Lithium dual complex grease was prepared through the second continuous saponification reaction of a complex gellant system whose essential components comprised of a selected hydroxy fatty acid, lithium hydroxide monohydrate and boric acid to have a fiber structure of chemical, thermal and mechanical stability at high temperatures. An optimum amount of complex gellant was found to be 14% (NLGI #2), and an addition of castor wax of 1.5% provided an excellent performance properties, especially. The oil separation, oxidation stability, water wash-out property, shear stability, extreme pressure and wear property of thus prepared were tested by the ASTM and KS methods, and a characteristic result was obtained.