• Biomedical Science Letters
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• v.19 no.1
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• pp.41-47
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• 2013

Pluripotent stem cells (PSCs) have lots of potential in biomedical sciences owing to its potential to differentiate into any kind of cells in the body. However, it is still a challenge to culture PSCs on a large scale for application to regenerative medicine. Herein, we introduce a synthetic polymer that enables large-scale suspension culture of human PSCs. By employing suspension culture, it became unnecessary to use conventional substrata such as mouse embryonic fibroblast (MEF) or Matrigel$^{TM}$, which are believed to be main causative sources of xenogeneic contamination in cultured human PSCs in vitro. Human PSCs were cultured in the medium in which elastin-like polypeptide (ELP) dissolved. The ELP in the medium became harden as temperature increases by transforming the medium into a semi-solid gel that supported growth of human PSCs in suspension. Gel-sol transition temperature of ELP can be adjusted by modifying the peptide sequence in which 5 amino acids, Val-Pro-Gly-Xaa-Gly, repeated sequentially. We constructed 3D suspension media having transition temperature around $33{\sim}35^{\circ}C$ using an ELP consisted of 40, 60, or 80 repeats of a monomer, which was Val-Pro-Gly-Val-Gly. Among the ELPs, ELP80 was chosen as the best ELP to support growth of human PSCs in suspension culture. This result suggests that the ELP80 can be a medium component for culturing human PSCs in large-scale.

• Journal of Korea Port Economic Association
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• v.26 no.4
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• pp.269-288
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• 2010

21 C is called the age of Culture and it is underlined in all the Areas of Human lifes. Among all activities, Culture oriented Thinking and activities and strategies through and for Culture establishing are emphasized. As Sea may appear as a image of longing and challenge for the unknown world, Port is understood as a link which connect Sea and Land. Sea, Island and Port are the basis of human lifes, economic working areas and communication spaces with nature. Sea and Port have been changed in accordance with human History as the space of Life, Work, Play and Imagination. The Maritime activities has been developed as the type of a Culture, including various diversities according to the time and space. This Paper suggested a definition of Maritime Culture and Theoretical review and groped introduction and strategies and countermeasures for expansion of systematic Maritime Culture. Maritime Culture not only enhance the quality of Citizen life but also contribute the progress of National economy increasing the quality of Culture, Turism and Environment and the expectation of it has been enlarged. It is needed to introduce and expand Maritime Culture systematically through theoretical framework suggested by this paper, and additional research may be necessary for the detailed solutions and countermeasures.

• Journal of the Korean Society for Precision Engineering
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• v.28 no.4
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• pp.526-533
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• 2011

This research is about the pulsatile pump system utilized in the perfusion bioreactor for the in vitro human tissue culture. A pulsatile pump system which can be applied to the culture of the vascular tissues including blood vessel is developed by using the idea of human heart's blood pumping into organs as followings: culture chamber, a pressurizing device which generates laminar pulsatile flow by controlling the x-sectional area of the culture media delivering tubing, a compliance chamber which supplies the pressuring device with a constant pressure, and a peristaltic pump which circulates the culture media in a circuit ranging from the culture chamber to the compliance chamber. The developed pulsatile pump system shows that a physiology of the human heart's blood pumping including pulsatile pressure waveform of systolic-diastolic pressure is well represented. Not only time domain but also frequency domain characteristics of pulsatile pump system which are necessary for the vascular tissue culture such as pulsatile pressure waveform's shape, the frequency, and the magnitude can be easily generated and manipulated by using the proposed system.

• Proceedings of the Botanical Society of Korea Conference
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• 1999.07a
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• pp.45-49
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• 1999

Plant cell culture is emerging to express bioactive foreign proteins because it has several advantages in that it is safe, economical, genetically stable and eukaryotic expression system comparing with other expression systems. However several limitations such as slow growth rate, low expression level and lack of well established down stream process need to be answered. As a preliminary approach to produce the immunologically interested molecules through the plant cell culture, we tested if granulocyte-macrophage colony stimulating factors (GM-CSFs) from both murine (mGM-CSF) and human (hGM-CSF) are produced as a biologically active form through plant cell culture. The murine and human GM-CSF genes were cloned into the plant expression vector, pBI121, and Ti-plasmid mediated transformation of tobacco leaves was conducted using Agrobacterium tumefaciens harboring both recombinant GM-CSF (rGM-CSF) genes. Cell suspension culture was established from the leaf-derived calli of transgenic tobacco plant. Northern blot analysis indicated the expression of the introduced mGM-CSF gene in both transgenic plant and cell suspension cultures. In addition, the biological activities of both murine and human GM-CSF from plant cell culture were confirmed by measuring the proliferation of the GM-CSF dependent FDC-PI and TF-1 cells, respectively.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.32 no.1
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• pp.103-108
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• 2024

Despite the development of the aviation industry, aircraft accidents caused by human errors by flight crews continue to occur. In order to reduce such human error accidents, it is important to strengthen flight-related regulations and establish a safety culture in which pilots themselves seek to ensure flight safety, rather than requiring flight crew members to follow them. In this study, the sub-concept of safety culture was classified into three latent variables (safety management, safety atmosphere, and process culture) and eight measured variables to investigate the safety culture awareness of domestic flight crew. The survey results were analyzed by type of airline and flight crew. The purpose of this study is to present a plan to improve the performance of revitalizing the safety culture of domestic flight crew through an empirical comparative analysis according to the number of flight hours and years of service at the airline.

• Proceedings of the SCSK Conference
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• 2003.09a
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• pp.85-96
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• 2003

Normal human skin, constantly challenged by environmental micro-organisms, has an innate ability to fight invading microbes through antimicrobial peptides. These peptides, described in both plant and animal kingdoms are able to inactivate a broad spectrum of micro-organisms. Mammalian defensins constitute one of the most common antimicrobial peptide family. Among the three human beta-defensins hBD1, hBD2 and hBD3 produced in epithelia, only hBD2 and hBD3 are inducible and additionally have been described as expressed by differentiated keratinocytes at site of inflammation and infection. The aims of these studies were to define a cell culture model in which the basal production of hBD could be detected and up-regulated in order to enhance skin auto-protection against micro-organisms. A specific Polymerase Chain Reaction method have been developed for hBD2 and hBD3 mRNA detection in non-differentiated monolayer keratinocytes cell culture. We have been able to demonstrate that in vitro, hBD2 and hBD3 expression in normal human keratinocytes could be detected and enhanced by TNF-alpha and IFN-gamma, in hypercalcic culture conditions. This research opened the possibility of the development of cosmetic active compounds, able to induce the expression of skin natural antibiotic peptides responsible about microflora ecology of the skin.

• Proceedings of the Costume Culture Conference
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• 2000.09a
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• pp.70-70
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• 2000

• The Research Journal of the Costume Culture
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• v.24 no.5
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• pp.653-669
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• 2016

This study examined how Chinese tourists' beauty tour preferences and attitudes toward Korean culture impacted their purchasing behaviors, repurchasing intentions, and the likelihood that they would recommend the products and services they received. Between the 10th and 21st of June, 2016, a total of 277 questionnaires were distributed in Seoul, Busan and Daegu using SPSS 21.0. On the surveys, beauty tour preferences were divided into the following categories: human service, high quality service, convenience accessibility & cost, and facility & atmosphere. The study found that high quality service and convenience & accessibility significantly affected respondents' purchasing intentions, with high quality service showing the higher standardized beta value. Friendliness to Korean culture also had a significant impact on beauty tour purchasing intentions. Preference for human service, high quality service, and facility & atmosphere significantly affected the purchasing intentions and the likelihood o f respondent recommendations, with higher standardized beta values shown (from high est to lowest) in the preference for facility & atmosphere, and preference for human service and high quality service respectively. Concerning perceptions of beauty products, preference for quality had a significant impact on the repurchasing intentions and intentions of respondents to make recommendations, as did the respondents', friendliness toward Korean culture. This study suggests that, to be most effective, beauty tours should emphasize human service and facility & atmosphere, as well as high quality service. In addition, preference for beauty services or products, and friendliness to Korean culture must be considered.

• Journal of Embryo Transfer
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• v.27 no.3
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• pp.189-192
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• 2012

Although embryonic stem cells (ESCs) or ES-like cells are reported from many mammalian species other than the mouse, the culture system for murine ESCs may not be suitable to the other species. Previously many other research groups have modified either human or mouse ESC culture systems for bovine ESC culture. In this study, we compared three different culture mediums consisting of DMEM, ${\alpha}$-MEM or KnockOut$^{TM}$-DMEM (KO), which are modified from human or mouse ESC culture system, for the generation of bovine ESCs. In this study, some pre-requisite events which are important for establishment and long-term propagation of ESCs such as inner cell mass (ICM) attachment on feeder cells, primary colony formation and sustainability after passaging. Once the ICM clumps attached on feeder cells, this was designated as passage 0. In regards to the rate of ICM attachment, ${\alpha}$-MEM was superior to the other systems. For primary colony formation, there was no difference between DMEM and ${\alpha}$-MEM whereas KO showed lower formation rate than the other groups. For passaging, the colonies were split into 2~4 pieces and passed every 5~6 days. From passage 1 to passage 3, DMEM system seemed to be appropriate for maintaining putative bovine ESCs. On the other hand, ${\alpha}$-MEM tended to be more suitable after passage 6. Although ${\alpha}$-MEM support to maintain a ES-like cell progenies to passage 15, all three culture systems which are modified from human or mouse ESC culture media failed to retain the propagation and long-term culture of putative bovine ESCs. Our findings imply that more optimized alternative culture system is required for establishing bovine ESC lines.

• Journal of the Ergonomics Society of Korea
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• v.33 no.4
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• pp.267-279
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• 2014

Objective: The objective of this study was to define the Dynamic Sitting (DS) through trend analysis and research on the Dynamic Chair (DC) and applied technologies. Background: The effects of changing posture on the human body have been studied to find out healthy sitting postures. It is believed that changing posture is effective in reducing disc pressure on spinal cord and preventing back pain and musculoskeletal disease. But, the definition of DS and trends of DC have not been researched yet. Therefore, trend analysis of DC and its applied technologies are required to define dynamic sitting posture. Method: We researched the type of occupant postures from previous studies. And then, sitting behaviors were classified into three types; (1) sitting and standing, (2) working and studying, (3) taking a rest. Results: Variety shapes of DC and applied technologies were found out. From the result, the trend of DC and applied technology were summarized from three perspectives. ; (1) changing the chair functions according to user's intention, (2) conversion of dynamic chair technologies to office chair mechanism, (3) enables the user to change their sitting posture without operating control device. Conclusion: From this study, we defined dynamic sitting posture and analyzed the trend of DC and its applied technologies. This result might be used to develop an office chair for healthy sitting. But further investigation is required to figure out the technologies and functions for development of healthy chair. Application: The results of the publishing trend analysis might help to determine design concept of office chair.