• Journal of Life Science
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• v.25 no.2
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• pp.214-222
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• 2015

Aeromonas hydrophila is the most common water fish pathogen and cause diseases such as hemorrhagic septicemia, dropsy, ulceration and asymptomatic septicemia. A. hydrophila secretes many extracellular products (ECPs) which contribute to effective infection, wide distribution and great adaptability to environmental changes. Crude ECPs of A. hydrophila CK257, a strain used in this study, exhibits a toxic activity to the animals including mouse, rabbit and fish. Toxic symptoms were indicated by tissue damage and skin injuries in animal. When ECPs were subcutaneously injected to animals, skin damages were observed, appearing like necrosis. Preliminary research demonstrated that the active factors are protein component. The crude ECPs were collected after ammonium sulfate precipitation of cell-free culture supernatant. ECPs were fractionated with the use gel filtration chromatography. Five ECP fractions were obtained, of which one fraction was found to be toxic to goldfish. MALDI-TOF analyses provided two interesting proteases called M35 and M28. Both M35 and M28 are known as metalloprotease. Accordingly, proteins in an active fraction exhibited caseinolytic activity. These proteins were difference of caseinolytic activity under different metallic ions. Also active fraction has elastolytic activity. These results suggested that peptidase M28 and M35 may be a candidate factor for tissue necrosis activity about infection with A. hydrophila.

• Journal of Microbiology and Biotechnology
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• v.17 no.1
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• pp.138-145
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• 2007

Anabaena sensory rhodopsin is a seven transmembrane protein that uses all-trans/13-cis retinal as a chromophore. About 22 residues in the retinal-binding pocket of microbial rhodopsins are conserved and important to control the quality of absorbing light and the function of ion transport or sensory transduction. The absorption maximum is 550 nm in the presence of all-trans retinal at dark. Here, we mutated Pro206 to Glu or Asp, of which the residue is conserved as Asp among all other microbial rhodopsins, and the absorption maximum and pKa of the proton acceptor group were measured by absorption spectroscopy at various pHs. Anabaena rhodopsin was expressed best in Escherichia coli in the absence of extra leader sequence when exogenous all-trans retinal was added. The wild-type Anabaena rhodopsin showed small absorption maximum changes between pH4 and 11. In addition, Pro206Asp showed 46 nm blue-shift at pH7.0. Pro206Glu or Asp may change the contribution to the electron distribution of the retinal that is involved in the major role of color tuning for this pigment. The critical residue Ser86 (Asp 96 position in bacteriorhodopsin: proton donor) for the pumping activity was replaced with Asp, but it did not change the proton pumping activity of Anabaena rhodopsin.

• Fisheries and Aquatic Sciences
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• v.22 no.6
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• pp.13.1-13.9
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• 2019

Background: Marine invertebrates are well known as pivotal bioresources with bioactive substances such as anti-inflammatory sterols, antitumor terpenes, and antimicrobial peptides. However, there are few scientific reports on chemical compositions and bioactivities of marine invertebrates from the East Sea of South Korea. Methods: In this study, chemical compositions and biological activities were evaluated on both 70% EtOH and hot water extracts of 5 species of marine invertebrates (Crossaster papposus japonicus, Actinostola carlgreni, Stomphia coccinea, Actinostola sp., and Heliometra glacialis) collected from the East Sea of South Korea. The antioxidant activities were measured by ABTS radical scavenging assay. The cytotoxicity and anti-inflammatory activity were evaluated using MTT and Griess reagents. Moreover, the antibacterial effect was evaluated using paper disc assay and minimum inhibitory concentration (MIC) assay. Results: In the results of antioxidant activities, 70% EtOH extract of A. carlgreni showed the highest activity ($IC_{50}\;0.19{\pm}0.03mg/ml$) compared to other extracts. Moreover, 70% EtOH extract of A. carlgreni could significantly suppress the nitric oxide (NO) production in lipopolysaccharide-induced RAW 264.7. All extracts treated under $400{\mu}g/ml$ have no cytotoxic effects on RAW 264.7 macrophages. In the antibacterial test, both 70% EtOH extracts of C. papposus japonicus and H. glacialis showed a significant antibacterial effect on Staphylococcus aureus. The MIC values were evaluated at 256 and $512{\mu}g/ml$, respectively. Conclusions: These results suggested the bioactive potentials of marine invertebrates from the East Sea of South Korea in pharmaceutical and nutraceutical applications.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.44 no.3
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• pp.317-325
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• 2018

This study was carried out to evaluate the antioxidant and whitening activities of Salix gracilistyla extracts. The total polyphenol contents of the extracts were 142.60-151.95 mg GAE/g and total flavonoid contents were 83.43-92.60 mg CE/g. In 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging assay, the 30% methanol extract showed the highest antioxidant activity ($IC_{50}$; $19.68{\mu}g/mL$). Tyrosinase inhibitory activity was similar in all four solvent extracts, and the highest inhibitory activity (35.18%) was obtained at a concentration of $200{\mu}g/mL$ of 30% ethanol extract. In addition, methanol extracts did not affect cell viability at all treatment concentrations and were found to significantly reduce the melanin content of B16F10 cells. As a result, it is considered that Salix gracilistyla extracts can be used as an effective cosmetic ingredient having antioxidant and whitening activity.

• Journal of the Korean Dietetic Association
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• v.12 no.2
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• pp.127-145
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• 2006

The purpose of this study is to develop an educational program for Korean traditional food culture, which is consisted of diverse activity factors and educational contents of the elementary students, and to transfer Korean traditional food culture to the next generation effectively. We have developed the program on the basis of FIB(Fun Integrated Behavior) approach derived from the activity-based education theory. This program is consisted of 32 subjects related with Korean traditional food culture, which is planned to perform in special activity classes for 2 semesters. An instruction guidebook for teachers and a workbook for students have been also developed. The traditional food culture educational program which is developed in this study could be used as a practical educational tool in 'dietary life and culture class' or 'special activity class' which is recently being introduced as the nutrition education curriculum in the elementary school. Furthermore, we expect this program to be able to contribute to transferring Korean traditional food culture to the next generation and reinforcing the elementary schoolers' diet behavior through inspiring them with a realization of the superiority of Korean traditional food culture.

• Journal of the Korean Electrochemical Society
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• v.10 no.4
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• pp.265-269
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• 2007

The effects of experimental variables for the electrochemical reduction of carbon dioxide by Carbon Monoxide Dehydrogenase (CODH) were investigated. It shows the pH optimum at 6.3 where the feasibility of electro-chemical reduction and the stability of CODH compromise each other. The optimum temperature for the reduction was at $60^{\circ}C$ where the enzyme shows the optimum activity although the solubility of carbon dioxide decreases as increasing temperature.

• Journal of the Korean Home Economics Association
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• v.39 no.8
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• pp.19-36
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• 2001

Recently, the demand for pubic welfare has been expended to the comprehensive services terms of cultural, medical and psychological aspects and provision of information. These various demands for welfare services to improve citizens'quality of life could be effectively met by an integrated community center covered small regions rather than many existing individual institutions focused on specific services covered wide regions. The purpose of this study was to develop the activity programs for a proposed new millennium community center The activity programs classified into five types (administrative services; information and counselling; health and sports; leisure and culture; and child care and educational services) and each type included various unique activity programs not only for specific age groups but also for all age groups. In order to operate a new millennium community center effectively, the legal supports and systematic organizations to manage the community center should be required. Discussions and recommendations for these issues were included in the study.

• The Bulletin of The Korean Astronomical Society
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• v.44 no.1
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• pp.75.3-75.3
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• 2019

Understanding how ram pressure stripping (RPS) affects the star formation activity of cluster galaxies is one of the important issues in astrophysics. To examine whether we can identify any discernible trend in the star formation activity of galaxies undergoing ram pressure stripping, we study the star formation properties of galaxies in the Virgo cluster for which high-resolution HI images are available. We first classify galaxies in the Extended Virgo Cluster Catalog into different stages of RPS based on their HI morphology, HI deficiency, and location in phase space. We then examine various star formation activity indicators of these galaxies, which include starburstiness, g - r color, and WISE [3.4]-[12] color. No noticeable enhancement in star formation was identified for galaxies undergoing early or active stripping. Our results suggest that star formation activity at best seems to be enhanced locally in such galaxies, making it challenging to detect with integrated photometry. With the combination of HI deficiencies and locations in phase space, we were instead able to capture the overall quenching of star formation activity with increasing degree of ram pressure stripping, which agree with previous studies.

• Educational Technology International
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• v.10 no.1
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• pp.79-105
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• 2009

The notion of contradiction from Cultural-Historical Activity Theory (CHAT) perspectives is known as an "engine" for the development of human practices because participants attempt to adjust their practices to resolve contractions. This study examines two middle school teachers' classroom practices from CHAT, focusing on the role of contradictions that emerged between their existing teaching practices and constructivist activities in the development of a student-centered technology-integrated learning environment. Findings indicated that teachers' awareness and resolution of contradictions played a large role in the development of a technology-supported student-centered learning environment, a culturally more advanced activity system: students displayed greater responsibilities for their learning and were guided to make effective decisions for their learning activity.

• Proceedings of the KSME Conference
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• 2001.06c
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• pp.357-360
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• 2001

Design Engineering Group, LG Production engineering Research Center has been developing The Integrated Design Environment enabling engineering design task with ease, speedy and accurate for several years targeting the design departments in LG Electronics. $ezDesign^{(R)}$ System is consisted by Engineering Database Management, Engineering Knowledge Management, 3D Design Application, Design Evaluation Method and Project Management. Engineering Database Management manage the design information effectively. Engineering Knowledge Management takes control of design knowledge from design engineering activity systematically. It is possible for the engineering designer to utilized 3D CAD easily by 3D Design Application. Design Evaluation Method can evaluate several design alternatives synthetically. In Project management System, Designer can simulate the project schedule and cost. In this report, We will introduce how design process can be innovated by way of $ezDesign^{(R)}$ System.