• Korean Journal of Agricultural Science
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• v.49 no.2
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• pp.175-184
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• 2022

The present study investigated the neuroprotective effects of Coreopsis lanceolate extract against hydrogen-peroxide (H₂O₂)-induced oxidative damage and cell death in pheochromocytoma 12 (PC12) cells. Reactive oxygen species (ROS), 2,2'-azinobis (3-ethylbebzothiazoloine-6-sulfonic acid) diammonium salt, and 1,1-diphenyl-2-picrrylhydrazyl radical scavenging activities, as well as the expression levels of proteins associated with oxidative damage and cell death were investigated. According to the results, C. lanceolate extract exhibited inhibitory activity against intracellular ROS generation and cell-damaging effects induced by hydroxyl radicals in a dose-dependent manner. Total phenolic and flavonoid contents were 22.3 mg·g^-1 gallic acid equivalent and 16.2 mg·g^-1 catechin equivalent, respectively. Additionally, a high-performance liquid chromatography (HPLC) assay based on the internal standard method used to detect phenolic compounds. The phenolic compounds identified in C. lanceolata extract contained (+)-catechin hydrate (5.0 ± 0.0 mg·g^-1), ferulic acid (1.6 ± 0.0 mg·g^-1), chlorogenic acid (1.5 ± 0.0 mg·g^-1), caffeic acid (1.2 ± 0.0 mg·g-1), naringin (0.9 ± 0.0 mg·g^-1), and p-coumaric acid (0.5 ± 0.0 mg·g^-1). C. lanceolata extract attenuated pro-apoptotic Bax expression levels and enhanced the expression levels of anti-apoptotic Bcl-2, caspase-3, and caspase-9 proteins. Therefore, C. lanceolata is a potential source of materials with neuroprotective properties against neurodegenerative disorders, such as Alzheimer's and Parkinson's diseases.

• The Korean Journal of Physiology and Pharmacology
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• v.17 no.3
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• pp.209-216
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• 2013

Soybean polyunsaturated phosphatidylcholine (PC) is thought to exert anti-inflammatory activities and has potent effects in attenuating acute renal failure and liver dysfunction. The aim of this study was to investigate the effects of PC in protecting multiple organ injury (MOI) from lipopolysaccharide (LPS). Six groups of rats (N=8) were used in this study. Three groups acted as controls and received only saline, hydrocortisone (HC, 6 mg/kg, i.v.) or PC (600 mg/kg, i.p.) without LPS (15 mg/kg, i.p.) injections. Other 3 groups, as the test groups, were administered saline, HC or PC in the presence of LPS. Six hours after the LPS injection, blood and organs (lung, liver and kidney) were collected from each group to measure inflammatory cytokines and perform histopathology and myeloperoxidase (MPO) assessment. Serum cytokines (TNF-${\alpha}$, IL-6 and IL-10) and MPO activities were significantly increased, and significant histopathological changes in the organs were observed by LPS challenge. These findings were significantly attenuated by PC or HC. The treatment with PC or HC resulted in a significant attenuation on the increase in serum levels of TNF-${\alpha}$ and IL-6, pro-inflammatory cytokines, while neither PC nor HC significantly attenuated serum levels of IL-10, anti-inflammatory cytokine. In the organs, the enhanced infiltration of neutrophils and expression of ED2 positive macrophage were attenuated by PC or HC. Inductions of MPO activity were also significantly attenuated by PC or HC. From the findings, we suggest that PC may be a functional material for its use as an anti-inflammatory agent.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.10
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• pp.136-152
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• 2017

The thermodynamic models, PC-SAFT (Perturbed-Chain Statistical Associated Fluid Theory) state equation and the Two-model approach liquid activity coefficient model NRTL (Non Random Two Liquid) + Henry + Peng-Robinson, for modeling the Rectisol process using methanol aqueous solution as the $CO_2$ removal solvent were compared. In addition, to determine the new binary interaction parameters of the PC-SAFT state equations and the Henry's constant of the two-model approach, absorption equilibrium experiments between carbon dioxide and methanol at 273.25K and 262.35K were carried out and regression analysis was performed. The accuracy of the newly determined parameters was verified through the regression results of the experimental data. These model equations and validated parameters were used to model the carbon dioxide removal process. In the case of using the two-model approach, the methanol solvent flow rate required to remove 99.00% of $CO_2$ was estimated to be approximately 43.72% higher, the cooling water consumption in the distillation tower was 39.22% higher, and the steam consumption was 43.09% higher than that using PC-SAFT EOS. In conclusion, the Rectisol process operating under high pressure was designed to be larger than that using the PC-SAFT state equation when modeled using the liquid activity coefficient model equation with Henry's relation. For this reason, if the quantity of low-solubility gas components dissolved in a liquid at a constant temperature is proportional to the partial pressure of the gas phase, the carbon dioxide with high solubility in methanol does not predict the absorption characteristics between methanol and carbon dioxide.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1996.05a
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• pp.76-79
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• 1996

Polypyrrole films were electrochemically synthesized under a constant current condition ranging from 50 ${\mu}$A/$\textrm{cm}^2$ to 2 mA/$\textrm{cm}^2$ with resultant high electrical conductivity about 100 S/cm. Specific energy of 70 Wh/kg and Ah efficiency of 97% were achieved during the cycling using liquid electrolyte system. On the other hand, consequences of the cycling were 51 Wh/kg and 95% using PEO$\sub$8/LiClO$_4$PC$\sub$5/EC$\sub$5/ solid electrolyte system. Polypyrrole film can be cycled stable and Ah efficiency is excellent, so it can be applicable to the cathode of Lithium secondary batteries.

• Proceedings of the KSME Conference
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• 2001.06b
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• pp.146-151
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• 2001

The Grand-Touring is a game motion simulator that simulates the race-car driving motion with three hydraulic cylinders which connect the platform and base in parallel. Its motion control system consists of the PC-based main controller and micro-controller based sub-controller. The former one process the dynamic image of race-car in response to the driver's action and computes the reference command for each cylinder and the latter one is designed for the tracking control of hydraulic cylinder and interfacing the auxiliary signals between various sensors/actuator and main controller. In this research, we developed the sub-controller that implements the required functions of Grand-Touring and prove the overall performance with experiments.

• The Bulletin of The Korean Astronomical Society
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• v.41 no.2
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• pp.32.4-33
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• 2016

활동성은하핵(AGN)의 거대 블랙홀 주변에 존재하는 플라스마 디스크의 구조나 물리적인 상태를 관측으로 직접 찾는 것은 AGN 중심부분에서의 제트 형성, 방출과정이나 에너지 수송과정을 조사하기 위해 중요한다. 지금껏 주로 센치미터파장 영역의 다주파 VLBI 관측으로 우리은하에서 가까운 AGN 속에 존재하는 10 pc 정도의 플라스마 디스크가 발견되어 있다만, AGN의 활동성을 정하고 있는 1 pc 이하의 스케일에서의 디스크 구조를 직접 관측한 결과는 아직 없다. 우리는 2015년8월부터 KVN 및 KVN과 일본 VERA로 구성되는 한일공동 VLBI 관측망(KaVA)을 이용해서 전파 은하 3C 84(z = 0.0176, 1 mas = 0.36 pc)의 밀리미터파장 모니터링을 진행하고 있다. KVN과 KaVA를 이용하면 1 pc 이하의 스케일로 3C 84의 중심구조를 고감도에서 분해할 수 있다. 이번 발표에서는 KVN 및 KaVA로 거의 동시에 실시한 관측결과를 중심으로 보고한다. 관측은 2016년2월22일(KaVA 43 GHz) 및 23일(KVN 86 GHz)에 실시되었다. 양 주파수의 이미지에서 종래의 센치미터 ~ 밀리미터파장 VLBI관측으로도 검출되어 있는 중심핵(C1) 및 남쪽에 약 3 mas 떨어져서 위치하는 로브(C3) 성분 뿐만 아니라 C1으로부터 북쪽에 약 2.5 mas 떨어져서 위치하는 새로운 성분(N1)을 검출하였다. N1의 검출 수준은 43, 86 GHz 모두 $6{\sigma}$이며, 양 주파수 사이에서 광학적으로 두꺼운 스펙트럼을 가지고 있다. 과거의 관측으로 측정된 C3의 겉보기 속도는 빛의 속도의 약 23%이며, 남북 로브의 구조와 운동의 대칭을 가정하면 N1이 도플러 분사출 효과 때문에 어두워지고 있는 가능성은 낮다. 따라서 C3에 대응하는 북쪽 N1로브로부터의 복사가 블랙홀 주변의 플라스마 디스크로 인해 저주파수에서 강한 흡수를 받고 있는 결과고 생각된다.

• Magazine of the Korea Concrete Institute
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• v.8 no.4
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• pp.141-148
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• 1996

The pulished works on Accelerated Curing Effect were generally performed around from 1960 to 1970th century for 18 to 24 hours - total curing periods. It is not possible to define the effect of temperature rise because those results were obtaine mainly by using the manually operated steam-curing tank. Thus, it may not be available to apply those data immediately on the domestic PC wall production line. The testing specimens were made from the standard mix proportion according to those of domestic PC factories to establish a basic data for the Accelerated Curing Effect. The experimental tests were conducted according to the conditions of each sub-curing periods. By comparing the results of compression tests on de-molded and 28-day water-curing specimens, we find that the most effective curing condition to obtain more than the required design strength after 28 day of water curing may be as follows: the presteaming period does not affect seriously and less than$30^{circ}C/hr$- the rate of temperature rise andless than $82^{circ}C$ - maximum temperature are necessary. It seems that post-curing procedure is very important factor to increase the effect of accelerated curing.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.sup3
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• pp.125-130
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• 2016

Nepeta cataria L. has been used in traditional medicine of some countries. Here the cytotoxic and apoptogenic activity of methanol extracts, n-hexane, dichloromethane, ethyl acetate, n-butanol, and acqueous extracts and the essential oil obtained from the aerial parts of the plant were evaluated with PC3, DU-145 and MCF-7 cell lines. Cell viability, histograms of PI stained fragmented DNA in apoptotic cells and Western blot analysis of proteins involved in the cascade of apoptosis were compared in all samples. Thirty components were identified as volatile, representing 99.7% of essential oil composition after GC-MS analysis of the oil obtained from aerial parts of the N. cataria by hydro-distillation. The major oil components of the essential oil were nepetalactone stereoisomers. Comparing IC50 values showed estrogen receptor positive PC3 cells were more sensitive to the cytotoxic effects of N. cataria in comparison with low hormone-receptor presenting DU-145 cells. Among multiple extracts and essential oils of the plant, only the ethyl acetate extract could significantly decrease cell viability in PC3 cells, in a concentration dependent manner. Ethyl acetate extract of N. cataria treated cells showed a sub-G1 peak in PC3 cells in a concentration dependent manner that indicates the involvement of an apoptotic process in ethyl acetate extract-induced cell death. Western blotting analysis showed that in PC3 cells treated with ethyl acetate (48 h) caspase 3 and PARP were cleaved to active forms. Overall, the results suggest that further analytical elucidation of N. cataria in respect to finding new cytotoxic chemicals with anti-tumor activity is warranted.

• Journal of Microbiology and Biotechnology
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• v.31 no.4
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• pp.584-591
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• 2021

Marine algae (seaweed) encompass numerous groups of multicellular organisms with various shapes, sizes, and colors, and serve as important sources of natural bioactive substances. The brown alga Ecklonia cava Kjellman, an edible seaweed, contains many bioactives such as phlorotannins and fucoidans. Here, we evaluated the antioxidative, neuroprotective, and anti-apoptotic effects of E. cava extract (ECE), E. cava phlorotannin-rich extract (ECPE), and the phlorotannin dieckol on neuronal PC-12 cells. The antioxidant capacities of ECPE and ECE were 1,711.5 and 1,050.4 mg vitamin C equivalents/g in the ABTS assay and 704.0 and 474.6 mg vitamin C equivalents/g in the DPPH assay, respectively. The dieckol content of ECPE (58.99 mg/g) was approximately 60% higher than that of ECE (36.97 mg/g). Treatment of PC-12 cells with ECPE and ECE increased cell viability in a dose-dependent manner. Intracellular oxidative stress in PC-12 cells due to ECPE and ECE decreased dose-independently by up to 63% and 47%, respectively, compared with the stress control (323%). ECPE reduced the production of the pro-apoptotic proteins Bax and caspase-3 more effectively than ECE. Early and late apoptosis in PC-12 cells were more effectively decreased by ECPE than ECE treatments. From the results obtained in this study, we concluded that ECPE, which is rich in phlorotannins, including the marker compound dieckol, may be applied to the development of functional materials for improving cognition and memory.

• Journal of rehabilitation welfare engineering & assistive technology
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• v.12 no.1
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• pp.20-28
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• 2018

In this research, for the smooth cultural life of seniors, we recruit 92 smart seniors (male: 22, female: 70) and survey their preferred content sub-genre. The survey is mainly based on the two devices (PC, Smartphone) to be used. As a result of the study, there was a little difference in preference on the web pages between both devices, the video contents showed the similar preference, regardless of the device. Also, sub-genres surveyed show higher correlations with similar sub-genres in other content genres. So, If the result of this study is reflected in the development of cultural contents and the composition of content pages, it will be helpful for senior to enjoy the improved cultural life by lowering entry barriers accessing digital media contents.