• Journal of Microbiology and Biotechnology
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• v.24 no.8
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• pp.1065-1072
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• 2014

Doxorubicin, produced by Streptomyces peucetius ATCC 27952, is tightly regulated by dnrO, dnrN, and dnrI regulators. Genome mining of S. peucetius revealed the presence of the IclR (doxR) type family of transcription regulator mediating the signal-dependent expression of operons at the nonribosomal peptide synthetase gene cluster. Overexpression of doxR in native strain strongly repressed the drug production. Furthermore, it also had a negative effect on the regulatory system of doxorubicin, wherein the transcript of dnrI was reduced to the maximum level in comparision with the other two. Interestingly, the overexpression of the same gene also had strong inhibitory effects on the production of actinorhodin (blue pigment) and undecylprodigiosin (red pigment) in Streptomyces coelicolor M145, herboxidiene production in Streptomyces chromofuscus ATCC 49982, and spinosyn production in Saccharopolyspora spinosa NRRL 18395, respectively. Moreover, DoxR exhibited pleiotropic effects on the production of blue and red pigments in S. coelicolor when grown in different agar media, wherein the production of blue pigment was inhibited in R2YE medium and the red pigment was inhibited in YEME medium. However, the production of both blue and red pigments from S. coelicolor harboring doxR was halted in ISP2 medium, whereas S. coelicolor produced both pigmented antibiotics in the same plate. These consequences demonstrate that the on and off production of these antibiotics was not due to salt stress or media compositions, but was selectively controlled in actinomycetes.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.11
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• pp.453-462
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• 2016

Since the Internet provides a way of expressing and sharing Internet users' mindsets, corporate marketers want to acquire measurable and actionable insights from web data. In the past, companies used to analyze the attitude, satisfaction, and loyalty of consumers toward their brands using survey data, whereas nowadays this is done using the big data extracted from Social Network Services. In this study, we propose a framework for clustering brand names using the social metrics gathered on social media. We also conduct a case study of the automobile industry to verify the feasibility of the proposed framework. We calculate the brand name distance for each pair of brand names based on the total number of times that they are mentioned together. These distances are used to project the brand name onto a 3-dimensional space using multidimensional scaling. After the projection, we found the clusters of brand names and identified the characteristics of each cluster. Furthermore, we concluded this paper with a discussion of the limitations and future directions of this research.

• Journal of Bio-Environment Control
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• v.4 no.1
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• pp.43-49
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• 1995

The main purpose of these studies were to clarify differences in Cheju - scoria and other solid media on quantity and quality of cherry tomatoes and on shift of component of the nutrient solution, and to use Practically Cheju-scoria as an excellent solid culture medium. The results obtained were summarized as follows ; 1. Among scoria plots, the rates of dry weights, fruits and their sugar-acid ratio were higher in the plot that was drained well with deep flow for one hour once a day. 2. Fresh fruit weights were lighter in rockwool and deep flow technique, but larger in scoria, Hyugashi (artificial gravel, $\Phi$10-12mm) and perlite in moving to higher flower cluster. 3. The results of analysis on microelement among solution components showed decrease of concentrations of P and K in the period of growth and development. 4. Yields and brix of cherry tomato showed a tendency to increase in rockwool and Hyugashi than anothers. 5. The concentration of fertilizer base was increased in general solution culture. Transpiration and absorption were similar in scoria plot and other media. 6. More studies of the Cheju-scoria development is required in order to use it as a solid medium for solution culture.

• Korean Journal of Plant Resources
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• v.19 no.2
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• pp.365-373
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• 2006

This study was conducted to develop the efficient propagation method of fern Phyllitis scolopendrium using In vitro culture. The influence of the origin of the donor explant sources (rhizome, stipe, three parts of blade) and the homogenization of explants was investigated. Rhizome and stipe explants showed the organogenic capacity among the five explant sources and plant regeneration was promoted by homogenization of culture material. Optimum condition for vigorous and excellent growth of multiple shoots was the half-strength MS medium with 1% sucrose concentration. Generally, addition of $NaH_2PO_4$ to media enhanced shoot multiplication. The highest rate of shoot proliferation was observed on the media containing $5{\mu}M$ NAA. Also, combination of activated charcoal $(0.1{\sim}0.2%)$ and growth regulators to growth medium prevented the formation of multiple bud primordia, 'nodule'-like bud clusters and improved the normal morphogenesis of sporopytes in P. scolopendrium.

• Proceedings of the Microbiological Society of Korea Conference
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• 2002.10a
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• pp.68-72
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• 2002

While the biosynthetic gene cluster encoding the pigmented antibiotic actinorhodin is present in the two closely related bacterial species, Streptomyces lividans and Streptomyces coelicolor, it normally is expressed only in S. coelicolor---generating the deep blue colonies responsible for the S. coelicolor name. However, multiple copies of the afsR2 gene, which activates actinorhodin synthesis, result in the ability of S. lividansto also synthesize large amounts of actinorhodin. Here we report that the phenotypic property that historicially distinguishes these two Streptomycesspecies is determined conditionally by the carbon source used for culture. Whereas growth on glucose repressed actinorhodin production in S. lividans, culture on solid media containing glycerol as the sole carbon source dramatically increased the expression of afsR2 mRNA---leading to extensive actinorhodin synthesis by S. lividansand obliterating its phenotypic distinction from S. coelicolor. afsR2 transcription under these conditions was developmentally regulated, rising sharply at the time of aerial mycelium formation and coinciding temporally with the onset of actinorhodin production. Our results, which identify media-dependent parallel pathways that regulate actinorhodin synthesis in S. lividans, demonstrate carbon source control of actinorhodin production through the regulation of afsR2 mRNA synthesis. The nucleotide sequences of afsR2 revealed two putative important domains; the domain containing direct repeats in the middle and the domain homologous to sigma factor sequence in the C-terminal end. In this work, we constructed various sized afsR2-derivatives and compared the actinorhodin stimulating effects in S. lividans TK21. The experimental data indicate that the domain homologous to sigma factor sequence in the C-terminal end of afsR2 plays a critical role as an antibiotic stimulating function. In addition, we also observed that the single copy integration of afsR2 regulatory gene into S. lividans TK21 chromosome significantly activates antibiotic overproduction.

• The Research Journal of the Costume Culture
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• v.17 no.2
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• pp.238-254
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• 2009

The purpose of this study were to examine fashion information acceptance and fashion information sources and to analyze the difference according to clothing shopping orientation among digital generation male consumers. The subject were 349 male who were belonging to digital generation as the digital era's new consumers familial with internet and various kinds of digital media. A self-administrated questionnaire was developed based on the results of previous researches. The data were analyzed by using frequency analysis, factor analysis, cluster analysis, ANOVA, Duncan test, $\chi^2$ test, multiple regression analysis by SPSS WIN 12.0 package. The results of this study are as follows: First, clothing shopping orientation of digital generation males were classified into 6 factors: fashion oriented, impulse buying, aesthetic pursuit, individuality pursuit, practical type and reasonable economy. Based on the factor scores, 3 clusters were identified; independent, unconcern, high involvement. Second, the high involvement shopping group utilized various information sources. On the other hand, the unconcerned shopping group was passive in utilizing information sources. Third, the fashion information acceptance of digital generation was classified into 5 factors: searching, leading, following, non-accepting, and delaying acceptance. All fashion information acceptance factors were affected by the information and communication media. Finally, The high involved type of shopping group accepted fashion information at its most and actively.

• Restorative Dentistry and Endodontics
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• v.41 no.2
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• pp.98-105
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• 2016

Objectives: The biocompatibility of two experimental scaffolds for potential use in revascularization or pulp regeneration was evaluated. Materials and Methods: One resilient lyophilized collagen scaffold (COLL), releasing metronidazole and clindamycin, was compared to an experimental injectable poly(lactic-co-glycolic) acid scaffold (PLGA), releasing clindamycin. Human dental pulp stem cells (hDPSCs) were seeded at densities of $1.0{\times}10^4$, $2.5{\times}10^4$, and $5.0{\times}10^4$. The cells were investigated by light microscopy (cell morphology), MTT assay (cell proliferation) and a cytokine (IL-8) ELISA test (biocompatibility). Results: Under microscope, the morphology of cells coincubated for 7 days with the scaffolds appeared healthy with COLL. Cells in contact with PLGA showed signs of degeneration and apoptosis. MTT assay showed that at $5.0{\times}10^4$ hDPSCs, COLL demonstrated significantly higher cell proliferation rates than cells in media only (control, p < 0.01) or cells co-incubated with PLGA (p < 0.01). In ELISA test, no significant differences were observed between cells with media only and COLL at 1, 3, and 6 days. Cells incubated with PLGA expressed significantly higher IL-8 than the control at all time points (p < 0.01) and compared to COLL after 1 and 3 days (p < 0.01). Conclusions: The COLL showed superior biocompatibility and thus may be suitable for endodontic regeneration purposes.

• Smart Media Journal
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• v.7 no.4
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• pp.30-36
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• 2018

Single domain model like DataLake framework is in spotlight because it can improve data efficiency and process data smarter in big data environment, where large scaled business system generates huge amount of data. In particular, efficient operation of network, storage, and computing resources in logical single domain model is very important for physically partitioned multi-site data process. Based on the advantages of Data Lake framework, we define and extend the concept of Connected Data Architecture and functions of DataLake framework for integrating multiple sites in various domains and managing the lifecycle of data. Also, we propose the design of CDA-based AI service and utilization scenarios in various application domain.

• Journal of the Korea Fashion and Costume Design Association
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• v.24 no.3
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• pp.33-48
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• 2022

This study aimed to investigate bag purchase behaviors according to materialism value. The subjects were 443 male and female adult consumers in their 20s to 50s. The research method was a survey, and the questionnaire consisted of questions on materialism value, bag purchase behaviors, and demographic characteristics. For data analysis, descriptive statistics, Cronbach's α, χ² test, factor analysis, cluster analysis, ANOVA, and Duncan's multiple range test were performed. The results of this study were as follows. First, materialism value was derived from three factors (happiness pursuit, possession-oriented, and success judgment). Second, subjects could be divided into three groups (happiness pursuit group, success judgment pursuit group, and immaterialism group) based on the materialism value variable. Third, the derived groups showed many differences in bag purchase behaviors. The happiness pursuit group considered all bag evaluation criteria factors (practicality, aesthetics, economy, symbolism) and bag purchasing information sources factors (mass media and personal sources) more than other groups, and showed a tendency to prefer select shops and complex shopping malls as bag purchasing places. In addition, the average annual cost and frequency of purchasing bags of this group were higher than those of other groups. The success judgment pursuit group considered symbolism as a bag evaluation criteria more than other groups, and considered personal sources as bag purchasing information sources more than mass media sources, and preferred luxury stores and department stores as bag purchasing places. On the other hand, the immaterialism group considered practicality and aesthetics as bag evaluation criteria and placed less importance on all information sources than other groups, and preferred Internet shopping malls as purchasing places. This group had the lowest average annual purchase cost and frequency among the three consumer groups. This study suggested that materialism value is a useful variable to segment male and female adult consumer markets effectively, and to understand the bag purchase behaviors of consumer groups divided by materialism value.

• Journal of the Korea Society of Computer and Information
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• v.28 no.5
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• pp.129-153
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• 2023

This study was conducted in the context of the Covid-19 pandemic by analyzing a large amount of press report frames regarding the Covid-19 vaccine which is of great public interest, in order to explore the role and direction of trusted media as core elements of crisis communication. The study period lasted for eight months beginning in November 2020 when the development of the Covid-19 vaccine was in progress until June 2021. Set-up as research subjects were the Chosun Ilbo, Joongang Ilbo, Dong-A Ilbo and Hankyoreh according to their public confidence rankings and number of readers.The analysis method used structured topic Modeling (STM) and semantic network analysis. As a result, based on a clear cluster of word structures and a central analysis value, a total of 64 relevant frames, 16 for each news company, were gathered. In the third phase a comparative analysis of the four news companies was carried out to verify the organizational degree of the frames and substantial differences.