• Journal of Plant Biotechnology
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• v.42 no.2
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• pp.77-82
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• 2015

We found that a long period of in vitro culture is a critical factor on the low transformation rate for a specific potato genotype, Solanum tuberosum L. var. Atlantic when phosphinothricin (PPT) was added to select putative transformants in a solid media. The fresh explants of the newly produced plants from a micro-tuber was able to increase the transformation rate significantly while the old explants prepared from a plant maintained for longer than 6 months in vitro by sub-culturing every 3 ~ 4 weeks resulted in a very low transformation frequency. However, Jowon cultivar was not so much influenced by the period of in vitro culture with high transformation rate (higher than 10.0%). Further research need to be explored for the reason why a particular potato genotype, Atlantic is more vulnerable than the Jowon cultivar during the regeneration stage resulting in the low transformation frequency.

• Plant Resources
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• v.7 no.1
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• pp.39-46
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• 2004

To demonstrate the importance of transformation efficiency in independent event, molecular and cytogenetic analysis were conducted with genomic DNA and chromosome of transgenic plants produced by Agrobacterium tumefeciens LBA4404 (pSBM-PPGN: gusA and bar). Selection ratios of putative transgenic calli were similar in independent experiments, however, transformation efficiencies were critically influenced by the type of regeneration media. MSRK5SS-Pr regeneration mediun, which contains 5 mgL$^{-1}$ kinetin, 2% (w/v) sucrose in combination with 3% (w/v) sorbitol, and 500 mgL$^{-1}$ proline, was efficient to produce transgenic plant of rice from putative transgenic callus in the presence of L-phosphinotricin (PPT). With MSRK5SS-Pr medium, transformation efficincies of Nagdongbyeo were significantly enhanced from 3.7% to 6.3% in independent callus lines arid from 7.3% to 19.7% in plants produced, respectively. Stable integration and expression of bar gene were confirmed by basta herbicide assay, PCR amplification and Southern blotting of bar gene, and fluorescence in situ hybridization (FISH) analysis using pSBM-PPGN as a probe. In Southern blot analysis, diverse band patterns were observed in total 44 transgenic plants regenerated from 20 independent PPT resistant calli showing from one to five copies of T-DNA segments, however, the transformants obtained from one callus line showed the same copy numbers with the same fractionized band patterns.

• International Journal of Internet, Broadcasting and Communication
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• v.15 no.2
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• pp.196-201
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• 2023

In recent years, virtual reality (VR) technology has been widely used in many industrial fields, especially in the fields of medical treatment, games, film and television, to improve the interaction between medical teaching and practical treatment. On the gaming side, the production of virtual reality gaming screens and scenes became increasingly popular, greatly expanding the form of the visual experience. But VR is no longer confined to the health care, education and entertainment industries. During this time, the news media industry has also begun to integrate virtual reality into interviews and user interactions. This study aims to analyze the development of VR technology from the perspectives of immersive VR news experience, real reporting, and prospects, and analyze and think about the interactive participation of media users, the transformation of traditional media, and the upgrading of practitioners' roles.

• Journal of electromagnetic engineering and science
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• v.14 no.2
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• pp.47-53
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• 2014

This paper presents a high gain and high harmonic rejection low-noise amplifier (LNA) for software-defined radio receiver. This LNA exploits the high quality factor (Q) series resonance technique. High Q series resonance can amplify the in-band signal voltage and attenuate the out-band signals. This is achieved by a source impedance transformation. This technique does not consume power and can easily support multiband operation. The chip is fabricated in a $0.13-{\mu}m$ CMOS. It supports four bands (640, 710, 830, and 1,070MHz). The measured forward gain ($S_{21}$) is between 12.1 and 17.4 dB and the noise figure is between 2.7 and 3.3 dB. The IIP3 measures between -5.7 and -10.8 dBm, and the third harmonic rejection ratios are more than 30 dB. The LNA consumes 9.6 mW from a 1.2-V supply.

• Journal of Microbiology and Biotechnology
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• v.11 no.2
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• pp.294-301
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• 2001

The effects of including glycine and isonicotinic acid hydrazide (INH) in the growth medium (Luria broth, LBG) on the subsequent lysozyme-imduced protoplast formation and transformation efficiency of Corynebacterium glutamicum were studied. The transformation efficiency of C. glutamicum AS019 increased up to 100-fold as the ocncentrationof glycine in the media increased from 0% to 5% (w/v), relative to cells grown in the absence of glycine. The presence of 5 mg/ml INH in the growth medium led to a further 10-fold increase in transformation efficiency. In addition, this transformation protocol was successfully applied to other strains of C. glutamicum. Both chemicals affected the mycolic acid attachment to the cell surface of C. glutamicum, when INH, the relative percentage of fatty acids of AS019 to the total lipids (mycolic acid plus fatty acids) decreased from 76.9% (in LBG) to 72.9% (in LBG-2% glycine) and 66.4% (in LBG-8 mg InG/ml), thereby suggeting that these chemicals also inhibit fatty acid synthesis.

• Journal of Plant Biotechnology
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• v.6 no.2
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• pp.69-75
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• 2004

Optimal protocol for efficient genetic transformation has been defined to aid future strategies of genetic engineering in pigeon pea with agronomically important genes. Transgenic pigeonpea plants were successfully produced through Agrobacterium tumefaciens-mediated genetic transformation method using cotyledonary node explants by employing defined culture media. The explants were co-cultivated with A. tumefaciens strain C-58 harboring the binary plasmid, pCAMBIA-1301 [con-ferring $\beta$-glucuronidase(GUS) activity and resistance to hygromycin] and cultured on selection medium (regeneration medium supplemented with hygromycin) to select putatively transformed shoots. The shoots were then rooted on root induction medium and transferred to pots containing sand and soil mixture in the ratio of 1:1. About 22 putative TO transgenic plants have been produced. Stable expression and integration of the transgenes in the putative transgenics were confirmed by GUS assay, PCR and Southern blot hybridization with a transformation efficiency of over 45%. Stable integration and expression of the marker gene has been confirmed in the TO and T1 transgenics through PCR, and Southern hybridization.

• Korean Journal of Plant Tissue Culture
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• v.22 no.4
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• pp.235-240
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• 1995

The development of selectable markers for transformation has been a major factor in the successful genetic manipulation of plant. We established a new selectable marker system for tobacco transformation using chimeric adenosine deaminase (ADA) gene, which confers resistance to cytotoxic adenosine analogues, 9-$\beta$-D-arabinofuranosyl adenine(Ara-A) and cordycepin. The transformants with the chimeric ADA gene in tobacco grew in the presence of normally lethal level of cytotoxic adenosine analogues, 100 $\mu$M Ara-A and 50 $\mu$M cordycepin. We successfully distinguished transformed shoot from non-transformed shoot on the same selectable media with cytotoxic adenosine analogues. In this selectable media, we were able to select seeds with/ without ADA gene from transgenic tobacco seeds. Theses results show that the mammalian ADA gene may serve as a new selectable marker for tobacco transformation.

• Journal of Technology Innovation
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• v.30 no.1
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• pp.1-20
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• 2022

Digital transformation refers to the economic and social effects of digitisation and digitalisation. Although digital transformation acts as a useful tool for economic/social development and enhancing the convenience of life, it can have negative effects (misuse of personal information, ethical problems, deepening social gaps, etc.). The government is actively establishing policies to promote digital transformation to secure competitiveness and technological hegemony, however, understanding of digital transformation-related risk issues and implementing policies to prevent them are relatively slow. Thus, this study systematically identifies risk issues of the future society that can be caused by digital transformation based on quantitative analysis of media articles big data through the Embedded Topic Modeling method. Specifically, first, detailed issues of negative effects of digital transformation in major countries were identified. Then detailed issues of negative effects of artificial intelligence in major countries and Korea were identified. Further, by synthesizing the results, future direction of the government's digital transformation policies for responding the negative effects was proposed. The policy implications are as follows. First, since the negative effects of digital transformation does not only affect technological fields but also affect the overall society, such as national security, social issues, and fairness issues. Therefore, the government should not only promote the positive functions of digital transformation, but also prepare policies to counter the negative functions of digital transformation. Second, the detailed issues of future social risks of digital transformation appear differently depending on contexts, so the government should establish a policy to respond to the negative effects of digital transformation in consideration of the national and social context. Third, the government should set a major direction for responding negative effects of digital transformation to minimize confusion among stakeholders, and prepare effective policy measures.

• Plant Biotechnology Reports
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• v.3 no.4
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• pp.277-283
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• 2009

One of the limitations to conducting maize Agrobacterium-mediated transformation using explants of immature zygotic embryos routinely is the availability of the explants. To produce immature embryos routinely and continuously requires a well-equipped greenhouse and laborious artificial pollination. To overcome this limitation, an Agrobacterium-mediated transformation system using explants of type II embryogenic calli was developed. Once the type II embryogenic calli are produced, they can be subcultured and/or proliferated conveniently. The objectives of this study were to demonstrate a stable Agrobacterium-mediated transformation of maize using explants of type II embryonic calli and to evaluate the efficiency of the protocol in order to develop herbicide-resistant maize. The type II embryogenic calli were inoculated with Agrobacterium tumefaciens strain C58C1 carrying binary vector pTF102, and then were subsequently cultured on the following media: co-cultivation medium for 1 day, delay medium for 7 days, selection medium for $4{\times}14$ days, regeneration medium, and finally on germination medium. The T-DNA of the vector carried two cassettes (Ubi promoter-EPSPs ORF-nos and 35S promoter-bar ORF-nos). The EPSPs conferred resistance to glyphosate and bar conferred resistance to phosphinothricin. The confirmation of stable transformation and the efficiency of transformation was based on the resistance to phosphinothricin indicated by the growth of putative transgenic calli on selection medium amended with $4mg\;1^{-1}$ phosphinothricin, northern blot analysis of bar gene, and leaf painting assay for detection of bar gene-based herbicide resistance. Northern blot analysis and leaf painting assay confirmed the expression of bar transgenes in the $R_1$ generation. The average transformation efficiency was 0.60%. Based on northern blot analysis and leaf painting assay, line 31 was selected as an elite line of maize resistant to herbicide.

• 한국경영정보학회:학술대회논문집
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• 2007.06a
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• pp.780-787
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• 2007

The Information and Communication Technologies (ICT) sector is undergoing a fundamental transformation. Determinant factors in this transformation process are deregulations and technological advancements. From the value chain perspective, industry convergence plays the most crucial role in the transformation of the established telecommunications and media industries. The objective of this paper is to validate the impact of convergence on the business performance using empirical data. To identify the various effects driven by industry convergence, we analyzed the relationships between firm's degree of convergence and the business performance using regression analysis. From the empirical result with the 2002-2005 data, it was found that the convergence across ICT sectors improves the business performance measured by Tobin's q significantly and this is only a recent phenomenon. These results are consistent with the conjecture that higher degree of convergence is becoming more associated with higher market value.