• Bulletin of the Korean Chemical Society
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• v.35 no.2
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• pp.425-430
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• 2014

Amyloidogenic proteins often exhibit fibrillar polymorphism through alternative assembly processes, which has been considered to have possible pathological implications. Here, firefly luciferase (LUC) is shown to induce amyloid polymorphism of ${\alpha}$-synuclein, the major constituent of Lewy bodies found in Parkinson's disease, by acting as a novel template. The drastically accelerated fibrillation kinetics of ${\alpha}$-synuclein with LUC required the nucleation center produced by the active enzyme of LUC. Fluorescent dye binding, transmission electron microscopy, and Fourier transformed infrared spectroscopy revealed the morphologically distinctive amyloid fibrils of ${\alpha}$-synuclein prepared in the absence or presence of LUC. As the altered morphological characteristics became inherent to the mature fibrils, those properties were inherited to next-generations via nucleation-dependent fibrillation process. The seed control, therefore, would be an effective means to modify amyloid fibrils with different biochemical characteristics. In addition, the LUC-directed amyloid fibrillar polymorphism also suggests that other cellular biomolecules including enzymes in general are able to diversify amyloid fibrils, which could be self-propagated with diversified biological activities, if any, inside cells.

• Bulletin of the Korean Chemical Society
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• v.24 no.5
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• pp.593-599
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• 2003

The nanoparticle magnetite of which diameter was about 3 nm was synthesized in a homogeneous aqueous solution without a template. The synthesized magnetite nanoparticle was easily oxidized to maghemite in an ambient condition. The magnetic properties of the ferrite nanoparticle show superparamagnetism at room temperature and its blocking temperature is around 93 K. Modifying the sequential adsorption method of metal bisphosphonate, we have prepared a multilayer thin film of the ferrite nanoparticle on planar substrates such as glass, quartz and Si wafer. In this multilayer the ferrite nanoparticle layer and an alkylbisphosphonate layer are alternately placed on the substrates by simple immersion in the solutions of the ferrite nanoparticle and 1, 10-decanediylbis (phosphonic acid) (DBPA), alternately. This is the first example, as far as we know, of nanoparticle/alkyl-bisphosphonate multilayer which is an analogy of metal bisphosphonate multilayer. UV-visible absorption and infrared reflection-absorption studies show that the growth of each layer is very systematic and the film is considerably optically transparent to visible light of 400-700 nm. Atomic force microscopic images of the film show that the surface morphology of the film follows that of the substrate in μm-scale image and the nanoparticle-terminated surface is differentiated from the DBPA-terminated one in nm-scale image. The magnetic properties of this ferrite/DBPA thin film are almost the same as those of the ferrite nanoparticle powder only.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2014.10a
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• pp.363-365
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• 2014

Internet baking, e-commerce, business processing, etc on smartphone handing could be possible in present days. Ambiguity between cyber and real life has made vulnerability on infrastructure, Gov't Service and National security by cyber terrorism. Especially, Lots of Infrastructure and Gov't Service based on Information Technology were exposed by Cyber terror. Legal system should be improved to keep from these threats. This paper proposed needs of cyber legal system by analyzing proposed cyber related code on Korean National Assembly, issue on Cyber Control Tower, National Cyber Security Industry and Human resource.

• Proceedings of the Korean Society of Crop Science Conference
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• 2022.10a
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• pp.253-253
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• 2022

Codonopsis lanceolata (C. lanceolata) has been widely used in East Asia as a traditional medicine to treat various diseases such as bronchitis, convulsions, cough, obesity, and hepatitis. C. lanceolata belonging to Campanulaceae contains bioactive compounds such as polyphenols, saponins, and steroids. However, despite the pharmacological significance of C. lanceolata, the genetic information of this plant is limited and there are few studies of its transcriptome. In this study, we constructed a unigene set of C. lanceolata using Pac-Bio sequencing. Furthermore, the reads generated from Pac-bio and Illumina sequencing were mixed and assembled using rnaSPAdes. All genes involved in the triterpenoid pathway, a major bioactive compounds of C. lanceolata, were searched from the two unigene sets and the expression profiles of these genes were analyzed. The results showed that lupeol, beta-amyrin, and dammarenediol synthesis genes were activated in the leaves and roots of C. lanceolata. In particular, the expression of genes related to lupeol synthesis was relatively high, suggesting that the main triterpenoid of C. lanceolata is lupeol. Transcriptome studies related to lupeol synthesis in C. lanceolata have been rarely reported. Lupeol has been reported to have pharmacological effects such as anti-inflammatory, anti-cancer, and anti-bacterial. This study suggests the importance of C. lanceolata as a lupeol producing plant.

• Journal of Korean Medicine for Obesity Research
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• v.18 no.2
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• pp.128-143
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• 2018

Objectives: The purpose of this study is to investigate the efficacy and the mechanisms of dietary supplements in cellulite treatment, and then to provide the theoretical and clinical basis for the cellulite treatment in Korean Medicine. Methods: We searched for articles from Korea, China, and English electronic database (Koreanstudies Information Service System [KISS], National Digital Science Library [NDSL], KMbase, Research Information Sharing Service [RISS], Oriental Medicine Advanced Searching Integrated System [OASIS], National Assembly Library, Korean Traditional Knowledge Portal, Google scholar, PubMed, Scopus, China National Knowledge Infrastructure [CNKI]) until April 2018. We chose clinical trial studies by inclusion criteria through titles, abstracts and articles. Results: A total of 10 studies were selected through search. The experimental group had shown more effective cellulite improvement in 90% of studies. Also, improvement of symptoms related with cellulite like pain, edema, heaviness and increase of skin surface temperature were observed in experimental group. In addition, the density of connective tissues of the dermal layer was increased in experimental group. Conclusions: The use of dietary supplements in cellulite treatment is thought to be effective through mechanisms that antioxidant efficacy, microcirculation improvement, interstitial matrix improvement, diuretic effect, and skin metabolic activity effect.

• Journal of Microbiology and Biotechnology
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• v.29 no.6
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• pp.999-1007
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• 2019

Middle East respiratory syndrome coronavirus (MERS-CoV) was first identified in Saudi Arabia in 2012 and related infection cases have been reported in over 20 countries. Roughly 10,000 human cases have so far been reported in total with fatality rates at up to 40%. The majority of cases have occurred in Saudi Arabia with mostly sporadic outbreaks outside the country except for the one in South Korea in 2015. The Korean MERS-CoV strain was isolated from the second Korean patient and its genome was fully sequenced and deposited. To develop virus-specific protective and therapeutic agents against the Korean isolate and to investigate molecular determinants of virus-host interactions, it is of paramount importance to generate its full-length cDNA. Here we report that two full-length cDNAs from a Korean patient-isolated MERS-CoV strain were generated by a combination of conventional cloning techniques and efficient Gibson assembly reactions. The full-length cDNAs were validated by restriction analysis and their sequence was verified by Sanger method. The resulting cDNA was efficiently transcribed in vitro and the T7 promoter-driven expression was robust. The resulting reverse genetic system will add to the published list of MERS-CoV cDNAs and facilitate the development of Korean isolate-specific antiviral measures.

• Journal of the Korean Society for Precision Engineering
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• v.27 no.1
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• pp.125-133
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• 2010

A versatile micro-robotic platform for micro/nano scale assembly has been demanded in a variety of application areas such as micro-biology and nanotechnology. In the near future, a flexible and compact platform could be effectively used in a scanning electron microscope chamber. We are developing a platform that consists of miniature mobile robots and a compact positioning stage with multi degree-of-freedom. This paper presents the design and the implementation of a low-cost and compact multi degree of freedom position sensor that is capable of measuring absolute translational and rotational displacement. The proposed sensor is implemented by using a CMOS type image sensor and a target with specific hole patterns. Experimental design based on statistics was applied to finding optimal design of the target. Efficient algorithms for image processing and absolute position decoding are discussed. Simple calibration to eliminate the influence of inaccuracy of the fabricated target on the measuring performance also presented. The developed sensor was characterized by using a laser interferometer. It can be concluded that the sensor system has submicron resolution and accuracy of ${\pm}4{\mu}m$ over full travel range. The proposed vision-based sensor is cost-effective and used as a compact feedback device for implementation of a micro robotic platform.

• Proceedings of the Korean Society of Dyers and Finishers Conference
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• 2012.03a
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• pp.88-88
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• 2012

Applied decanol and nonanol provided more weight loss than applied heptanol and octanol. PET using decanol showed the highest weight loss than other alcohols applied. Sodium hydroxide caused weight loss in PET fabrics because terephthalic acid and ethylene glycol were separated by the hydrolysis of the ester group in the PET chains. The terephthalic acid was neutralized to disodium terephthalate and the reaction results in weight loss in the PET fabrics. The weight loss increased with increasing hydrolysis time because disodium terepthalate was water soluble and the reaction was not reached at equilibrium. Pretreatment alcohols increased water absorption, especially in case of PET applied decanol revealed the highest water absorption. PET applied decanol showed 400% of initial water absorption, and PET applied nonanol revealed 250% of initial water absorption. However, the pristine PET showed 90% initial water absorption, and it revealed 230% maximum water absorption as compared to other alcohols. Also, PET applied decanol, nonanol, octanol and heptanol showed 600%, 400%, 350% and 300% maximum water absorption, respectively. The result implied alcohol length affected on water absorption of PET fibrous assembly. This implies that the microvoid of the PET surface hold water molecules. Surface morphology of PET appears that the pretreatment reagent attacks almost entire surface of the fiber, causing surface etching. As the surface etching progresses, it propagates inside the fiber, resulting in the formation of elongated cavities on the surface.

• Applied Chemistry for Engineering
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• v.23 no.5
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• pp.445-449
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• 2012

The activation process of the membrane-electrode assembly (MEA) is important for the mass production of the polymer electrolyte membrane fuel cell. The conventional activation process for the MEA requires excessive time and hydrogen gas and it might become the barrier for the commercialization of the fuel cell. The conventional activation process is based on hydrolysis of ion conducting membrane. In the study, we suggest the cyclic voltammetry (CV) technique as an on-line activation process and the CV activation process consists of two steps : 1) the humidification of the polymer electrolyte membrane and the electrode with 100% RH humidified nitrogen ($N_{2}$) gas, and 2) the removal step of the oxide layer on the surface of the Pt catalyst with CV cycling. The cycling reduces the activation time of the MEA by 2.5 h and use of hydrogen gas by 1/4.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.34 no.11
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• pp.1697-1703
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• 2010

Hydraulic hoses are used as pipelines for transferring power from hydraulic systems in various machineries such as construction equipments, automobiles, and aircraft. Hydraulic hoses protect the system from vibration or impacts, and they are being used to transfer energy in all segments of the industry. In order to protect the system from various external environmental conditions, hydraulic hose assemblies must be able to withstand a wide range of temperatures and pressures, as well as variations in other factors. In previous studies, an acceleration model for the hydraulic hose assembly was developed by taking into account only one of the acceleration factors (temperature or pressure). Therefore, the objective of this study is to develop a comprehensive acceleration model that takes both temperature and pressure into consideration.