• Korean Chemical Engineering Research
• /
• v.44 no.1
• /
• pp.58-64
• /
• 2006

We successfully isolated human anagen hair follicles from human scalp skin by microdissection and tried to culture them under various conditions. First we confirmed negative effect of serum on human hair follicle organ culture. As a next step serum-free medium compositions, Philpott medium, IMDM, and DHGM (Dongguk hair growth medium) were tried. Philpott medium is a general medium for hair organ culture based on Williams' E medium and DHGM is a special self-developed medium containing high amino acids and vitamins (B group) composition. As results, hair follicle in Philpott medium and IMDM showed anagen phase morphological structure, but rapid loss of hair elongation, low alkaline phosphatase expression, and very low expression of CK19. It is thought these hair follicles rapidly regressed from apoptosis. However, hair follicles in DHGM showed long term anagen phase morphological structure, continuous hair elongation, high alkaline phosphatase, and CK19 expression. These results demonstrate that high amino acids and vitamins (B group) composition are essential to in vitro long term human hair follicle organ culture and this culture medium will be useful in basic study of hair biology or application study to the development of alopecia treatment drugs.

• Korea Journal of Hospital Management
• /
• v.12 no.1
• /
• pp.100-127
• /
• 2007

The purpose of this study is to reform the productive industrial relations in hospital. Because the industrial relations of hospital is antagonistic each other and this problem cause a low productivity. In Korea, hospitals maintain their ownership structure, strategy is controlled by government, short process of management, and culture of grade. The executive of hospital doesn't gain the confidence of union. This circumstances is related with the antagonistic industrial relations. This research is to analyze hospital management system through experiential and literature study, and is to present a reform strategies for cooperative industrial relations of improving productivity in hospital. As a results, if the hospital manager hopes to improve productivity, they should introduce expert management system rather than ownership and management system. And it is need to execute the hospital initiative strategy rather than to depend on the government. Moreover, the hospital can achieve productive industrial relations as a middle-long term visions in management process and horizontal organization culture. Although this study is limited by literature research, it will contribute to settle productive industrial relations in hospital and to accomplish the additional study.

• Journal of Microbiology and Biotechnology
• /
• v.11 no.5
• /
• pp.863-869
• /
• 2001

A systematic study of microbial fuel cells comprised of alkalophilic Bacillus sp. B-31 has been carried out under various operating conditions. A significant amount of electricity was generated when redox mediators were used. Among the phenothiazine-type redox dyes tested, azure A was found to be the most effective both in maintaining a high cell voltage and for the long-term operation. The maximum efficiency was and for the long-term operation. The maximum efficiency was obtained at ca. $50^{\circ}C$ giving an open circuit voltage of 0.7V. A small change in temperature did not significantly affect the cell performance, but a rapid decrease in performance was observed below $20^{\circ}C$ and above $70^{\circ}C$. It was noticeable that fuel cell efficiency and discharge pattern depended strongly on the carbon source used in the initial culture medium. Regardless of the initial carbon sources, only glucose and trehalose were utilized as substrates. Galactose, however, was not substantially utilized except when galactose was used in the initial medium. Glucose, in particular, showed $87\%$ coulombic efficiency, which was the highest value ever reported, when Bacillus sp. was cultured in a maltose-containing medium. This study demonstrates that highly efficient microbial fuel cells can be constructed with alkalophilic microorganisms by fine-tuning the operating conditions and by carefully selecting carbon sources in the initial culture medium.

• Korean Journal of Plant Resources
• /
• v.34 no.1
• /
• pp.17-22
• /
• 2021

Plants regenerated from in vitro cultures carry chromosomal variations, especially in long-term culture. Reducing the duration of plant tissue culture is one of the ways to reduce genetic and epigenetic changes. In this study, we reduced the duration of long-term culture and repeat subculture using small bulblets derived from bulb scales in two lily cultivars. The adventitious bulblets derived from bulb-scale tissue were cultured on three different media containing Murashige and Skoog (MS) basal medium supplemented with 1 g/L Charcoal, MS medium containing 0.3 mg/L IAA and 0.4 mg/L BA hormone with or without Charcoal, respectively. About seven weeks later, the number of newly propagated multiple shoots in the two media, A and B media, showed little differentiation. Compared to both media, the number of propagated multiple shoots increased 5-fold in MS medium containing 0.3 mg/L IAA and 0.4 mg/L BA hormone without Charcoal (C medium). The number of propagated multiple shoots ranged from 5 to 6 and 4 to 6 with an average of 5 in TropicalPink and GreenStar cultivars, respectively. The flow cytometric measurements indicated no variation in the ploidy level between control and in vitro propagated plants.

• BMB Reports
• /
• v.48 no.12
• /
• pp.668-676
• /
• 2015

Pluripotent stem cells only exist in a narrow window during early embryonic development, whereas multipotent stem cells are abundant throughout embryonic development and are retainedin various adult tissues and organs. While pluripotent stem cell lines have been established from several species, including mouse, rat, and human, it is still challenging to establish stable multipotent stem cell lines from embryonic or adult tissues. Based on current knowledge, we anticipate that by manipulating extrinsic and intrinsic signaling pathways, most if not all types of stem cells can be maintained in a long-term culture. In this article, we summarize current culture conditions established for the long-term maintenance of authentic pluripotent and multipotent stem cells and the signaling pathways involved. We also discuss the general principles of stem cell maintenance and propose several strategies on the establishment of novel stem cell lines through manipulation of signaling pathways.

• Molecules and Cells
• /
• v.37 no.6
• /
• pp.473-479
• /
• 2014

Spermatogonial stem cells (SSCs, also called germline stem cells) are self-renewing unipotent stem cells that produce differentiating germ cells in the testis. SSCs can be isolated from the testis and cultured in vitro for long-term periods in the presence of feeder cells (often mouse embryonic fibroblasts). However, the maintenance of SSC feeder culture systems is tedious because preparation of feeder cells is needed at each subculture. In this study, we developed a Matrigel-based feeder-free culture system for long-term propagation of SSCs. Although several in vitro SSC culture systems without feeder cells have been previously described, our Matrigel-based feeder-free culture system is time- and cost-effective, and preserves self-renewability of SSCs. In addition, the growth rate of SSCs cultured using our newly developed system is equivalent to that in feeder cultures. We confirmed that the feeder-free cultured SSCs expressed germ cell markers both at the mRNA and protein levels. Furthermore, the functionality of feeder-free cultured SSCs was confirmed by their transplantation into germ cell-depleted mice. These results suggest that our newly developed feeder-free culture system provides a simple approach to maintaining SSCs in vitro and studying the basic biology of SSCs, including determination of their fate.

• Journal of the Korea Society of Computer and Information
• /
• v.25 no.8
• /
• pp.119-128
• /
• 2020

In this research, a survey was done on two hundred and forty-six elders who receive care through LTC to verify the effect of market attributes on the user satisfaction of the Long-therm Care Service. The collected data were analyzed through SPSS 23.0 statistics program. This study reveals the following results: First, in service tangibility, competitiveness, administrative regulation, organizational process, and autonomy in choice all have a positive relation with user satisfaction. Second, in the aspect of credibility, house ownership, competitiveness, administrative regulation, and freedom in choice show a positive-relation with user satisfaction. Third, in responsiveness, the scale of the organization, monthly income, competitiveness, administrative regulation, organizational process, and autonomy in choice have a positive effect on user satisfaction. Forth, in assurance ability, monthly income, competitiveness, administrative regulation, organizational process, and autonomy in choice also positively affected user satisfaction. Lastly, in the aspect of perceptual openness, competitiveness, administrative regulation, organizational culture, organizational process, and autonomy in choice show a positive relationship with user satisfaction.

• Journal of Navigation and Port Research
• /
• v.47 no.4
• /
• pp.191-201
• /
• 2023

The provision of onboard Internet services is recognized as one of the measures to enhance the appeal of seafarers and improve seafarer welfare. This study aims to investigate the influence of seafarers' leisure activities using the Internet on shipboard culture. Shipboard culture was examined using Hofstede's cultural dimensions theory. An empirical analysis was conducted on crewmembers regarding their Internet-based leisure activities and the shipboard culture. As a result, it was observed that sociability activities through the Internet while onboard significantly influenced power distance, uncertainty avoidance, and long-term orientation. The investigation of shipboard culture revealed uncertainty avoidance, masculinity, and long-term orientation, along with low power distance and individualism cultures. In addition, an analysis of shipboard culture according to seafarers' characteristics showed significant differences in certain shipboard cultures based on seafarers' attributes.

• Journal of Practical Engineering Education
• /
• v.12 no.1
• /
• pp.93-100
• /
• 2020

To qualitative improvement in addition to the quantitative growth of field placement, efforts to reduce short-term (4 weeks) and mid-term professional practice (8 weeks) and to increase the proportion of long-term term professional practice (12 weeks or more) are increasing at university sites. There are the problems: the absence of systematic and specialized field placement curriculum of the short-term and mid-term professional practice, the participation of university field placement increases, companies do not prefer to participate in its program and students hesitate to apply to long-term practice due to their major. In order to solve these problems, this paper proposes the IPBP(Industry Problem Based professional Practice) based on Gyeongbuk K University which the students solve the company's difficulties during the field placement with their professor if need. In order to build a win-win field practice culture with participating companies, we suggest that the IPBP solution field practice presented in this paper is one of the good models.

• Korean System Dynamics Review
• /
• v.10 no.2
• /
• pp.81-102
• /
• 2009

Based on various employment and technology data in the cultural sector from the mid-1990s to the mid-2000s in Seoul, Korea, this research examines whether technology- and human resource-oriented programs exert significant impact on creative manpower, R&D technology level and tolerance. After briefly introducing Seoul's trends in the culture industry, it tries to explain major reinforcing and balancing loops. The stock-flow diagram of the culture industry in Seoul is applied to estimate relative effectiveness of technology- and human resource-oriented cultural programs cultural programs. Judging from a series of simulated experiments, technology-oriented cultural programs are essential to increase creative manpower and R&D technology level in the short term. For the first half of research period, this research finds that human resource-oriented cultural programs put forth minimal impact, if they even exist at all. The trends, however, are reversed in the long term: Both size of creative manpower and R&D technology level absolutely depend on human resource-oriented cultural programs in the second half.