• Journal of Microbiology and Biotechnology
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• 제5권4호
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• pp.234-237
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• 1995

Production of new flavanol derivatives with cytotoxic activity, gericudranin A and B, was studied by using hairy root cultures of Cudrania tricuspidata. Schenk and Hildebrandt (SH) medium was chosen for root growth and gericudranin production. After 35 days culture in a half-strength liquid SH medium containing $30g^{glucose}$/l, hairy root growth reached $138g^{FW}$/I and gericudranin A and B were produced at concentrations of 27mg/l and 21 mg/l, respectively. It was also observed that the contents of gericudranin A and B in hairy root were eight and six times higher than those of cudraniae radix, respectively.

• The Korean Journal of Malacology
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• 제30권3호
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• pp.235-242
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• 2014

This study was conduct to investigate the effect of Intermediate culture types on the growth and survival rate of the abalone, Haliotis discus hannai, in net cage and indoor tank. Intermediate cultures were to determine there that was to setting at marine net cage culture (NCC) in net cage, floor culture (FC), net floor culture (NFC), double shelter culture (DSC) and indoor net cage culture (INCC) in indoor tank, in two replicate. In the growth performance of juvenile abalone reared through intermediate culture, that the absolute growth rate ($AGR_{SL}$, $AGR_{SB}$), daily growth rate ($DGR_{SL}$, $DGR_{SB}$), and specific growth rate ($SGR_{SL}$, $SGR_{SB}$) to the shell length $(_{SL})$ and shell breadth $(_{SB})$ of NCC were higher than those of different groups (P < 0.05). As weight gain (WG), daily weight gain (DWG) and specific weight gain (SWG) to body weight through intermediate culture types in indoor tank was not significant. Also that, survival rate among experimental groups of intermediate culture in indoor tank was not significant. Therefore, these results is showed that should to cultivate for net cage so that intermediate culture of juvenile abalone over 2 cm, accordingly research to effective progress of juvenile abalone intermediate culture in indoor tank be should from various reason as well as feed and rearing condition.

• Korean Journal of Plant Resources
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• 제20권3호
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• pp.251-254
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• 2007

This study was conducted to investigate the optimal plant growth regulator level for the shoot formation of Lycium chinense Mill. In vitro plant propagation was developed for leaf explants of boxthorn. Leaf explants were cultured on MS medium supplemented with cytokinins (BA and 2-iP) alone. Plants were successfully regenerated through in vitro culture by using leaf explants of boxthorn grown in the field. After 4 weeks of culture, 58% of shoot formation had developed from the leaf explants. The shoot formation rate of 'Jangmyeong' was highest followed by 'Myeongan', ;Cheondae', and 'Bullo'. The use of 0.2mg/L BA was critical for enhanced production of shoot formation and resulted in 58% of the culture producing shoot formations. Regenerated plantlets transplanted to pots were developed and successfully acclimatized to greenhouse.

• Journal of the Korean Society for Aviation and Aeronautics
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• 제23권3호
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• pp.88-93
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• 2015

Among other various aspects of safety culture, this research has considered safety culture from the view of aviation. A tool to examine aviation safety culture has been developed on the basis of Global Aviation Safety Network's safety culture survey. Using this tool, the degree of perception of Korean national carriers' pilots in safety culture has been examined three times for the period from 2002 to 2015. Compared to an initial result of the survey in 2002, results in 2008 and 2015 demonstrate that safety culture among pilots has rapidly changed from negative and bureaucratic to positive. Hence, it is expected that positive index of safety culture will increase 28% (total approximate 90%) in 2020.

• Culinary science and hospitality research
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• 제14권4호
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• pp.292-305
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• 2008

This study examines the relationships among the leadership of hotel managers, organizational culture, and business performance with an empirical analysis. The results of analyzing various factors are as follows. Leadership can be divided into 'democratic leadership' and 'authority leadership'. Organizational culture can also be divided into 'adhocracy culture', 'clan culture', 'hierarchy culture', and 'market culture' while business performance into 'nonfinancial performance' and 'financial performance'. After that, canonical correlation analyses between leadership and organizational culture, organizational culture and business performance, and leadership and business performance were conducted.

• Journal of the Korean Society for information Management
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• 제35권4호
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• pp.285-308
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• 2018

Knowledge utilization is an activity directly linked to organizational capacity and is the most essential activity in knowledge management that is to produce new values. Thus, systematic and comprehensive understanding of factors and the environment that affect knowledge utilization are needed. The purpose of this study is to investigate the effects of information culture and organizational culture on knowledge utilization. For this, data were collected from 300 workers from 6 institutions including government-funded research institutes, libraries, and cooperation research institutes. This study analyzes the effects of six aspects of information cultures and four organizational culture types on knowledge utilization. The results show that information cultures(control, transparency, proactiveness) and organizational culture (The Clan Culture, The Adhocracy Culture, The Market Culture, The Hierarchy Culture) are significantly influential factors for the knowledge utilization. Based on results, this study provides the implication of knowledge sharing in the organizations and suggests further studies.

• Food Science of Animal Resources
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• 제40권4호
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• pp.659-667
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• 2020

Muscle stem cells isolated from domestic animals, including cows and pigs, were recently spotlighted as candidates for the production of alternative protein resources, so-called cultured meat or lab-grown meat. In the present study, we aimed to optimize the in vitro culture conditions for the long-term expansion of pig muscle stem cells via the screening of various signaling molecules. Pig muscle stem cells were collected from the biceps femoris muscles of 3-d-old crossbred pigs (Landrace×Yorkshire×Duroc, LYD) and cultured in minimum essential medium-based growth media. However, the pig muscle stem cells gradually lost their proliferation ability and featured morphologies during the long-term culture over two weeks. To find suitable in vitro culture conditions for an extended period, skeletal muscle growth medium-2, including epidermal growth factor (EGF), dexamethasone, and a p38 inhibitor (SB203580), was used to support the stemness of the pig muscle stem cells. Interestingly, pig muscle stem cells were stably maintained in a long-term culture without loss of the expression of myogenic marker genes as determined by PCR analysis. Immunostaining analysis showed that the stem cells were capable of myogenic differentiation after multiple passaging. Therefore, we found that basal culture conditions containing EGF, dexamethasone, and a p38 inhibitor were suitable for maintaining pig muscle stem cells during expanded culture in vitro. This culture method may be applied for the production of cultured meat and further basic research on muscle development in the pig.

• Korean Journal of Culture and Social Issue
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• 제14권1호_spc
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• pp.409-414
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• 2008

The roles-grafting research is an approach to educational studies intended to graft five roles of supervisors, graduate students, teachers, principals and administrators. The approach is divided into four chained and cyclical aspects: drafting research blueprint, revising research blueprint, executing research blueprint and assessing performances. The approach maintains five basic principles: principles of inheritance, innovation, practicality, scientific basis and grafting. It is a paradigm of innovative research that has been developed in China that is worth a thorough investigation and extensive analysis.

• Toxicological Research
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• 제14권3호
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• pp.357-363
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• 1998

The teratogenic potential of the anticonvulsant drug phenytoin (PHT) has been well documented both in the human and in the experimental animals. However there are few reports on the effects of PHT on embryonic development in rats in vitro. The present study was performed to evaluate the teratogenic effects of PHT using whole-embryo culture system in rats. Sprague-Dawley rat embryos were explanted on gestational day (GD) 9.5 and cultured for 48 hrs in the immediately centrifuged and heat-inactivated rat serum containing 0,25,50, or $100{\mu}g$ PHT/mL. At the end of culture period the embryos were scored for morphological development according to the procedure of Van Maele-Fabry, and their total protein contents were determined. At 100 ${\mu}$g/mL of culture medium. PHT caused significant reduction in developmental score and protein content of embryos and a high incidence morphological abnormalities (100%). Characteristic malformations included altered yolk and embryonic circulation, craniofacial hypoplasia, neural tube schisis, branchial arch defects, abnormal ratation, and limb bud hypoplasia, among others. There were no adverse effects on embryonic growth and development at concentrations of 25 and 50 ${\mu}$g /mL of culture medium. The results indicated that the dysmorphogenic effect of PHT on cultured embryos is due to a direct interference with embryonic development.

• Tuberculosis and Respiratory Diseases
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• 제83권3호
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• pp.211-217
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• 2020

The gold standard method for diagnosis of tuberculosis is the isolation of Mycobacterium tuberculosis through culture, but there is a probability of cross-contamination in simultaneous cultures of samples causing false-positives. This can result in delayed treatment of the underlying disease and drug side effects. In this paper, we reviewed studies on false-positive cultures of M. tuberculosis. Rate of occurrence, effective factors, and extent of false-positives were analyzed. Ways to identify and reduce the false-positives and management of them are critical for all laboratories. In most cases, false-positive is occurring in cases with only one positive culture but negative direct smear. The three most crucial factors in this regard are inappropriate technician function, contamination of reagents, and aerosol production. Thus, to reduce false-positives, good laboratory practice, as well as use of whole-genome sequencing or genotyping of all positive culture samples with a robust, extra pure method and rapid response, are essential for minimizing the rate of false-positives. Indeed, molecular approaches and epidemiological surveillance can provide a valuable tool besides culture to identify possible false positives.