• Journal of Microbiology and Biotechnology
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• v.10 no.1
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• pp.107-110
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• 2000

Elicited cells with methyl jasmonate continued to produce benzophenanthridine alkaloids throughout medium changes in suspension cultures of Eschscholtzia californica. Large increases in alkaloid production were observed by re-elitations with medium changes. The total alkaloid production increased during the successive elicitation steps reaching a maximum level on the 4th elicitation. The highest total alkaloid produced was 250 mg/I, which was 20fold higher than that of the single elicitation and 4-fold higher than that of the normal culture without elicitation. The large increases in alkaloid production in successive re-elicitations with medium changes are believed to be caused by the accumulation of the signal transduction compound, jasmonate.

• Korean Journal of Cognitive Science
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• v.20 no.2
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• pp.197-223
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• 2009

Three studies re-examined Shafer's(1993) response compatibility hypothesis in decision making. This hypothesis proposes that participants choose or reject an option when its features are compatible with either a selection or a rejection response. By changing the description of options into sentences and by the prior presentation of either a selection or a rejection question, we obtained results fairly consistent with the predictions of the response compatibility hypothesis. Based on the analysis of both previous and present results, we discussed the importance of preference elicitation methods when constructing options. Our results were compared to those of recent studies.

• Biotechnology and Bioprocess Engineering:BBE
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• v.10 no.2
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• pp.162-165
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• 2005

A series of fluorine and hydroxyl containing jasmonate derivatives, which were chemically synthesized in our institute, were investigated for their effects on the biosynthesis and heterogeneity of ginsenosides in suspension cultures of Panax notoginseng cells. Com-pared to the control (without addition of elicitors), $100{\mu}M$ of each of the jasmonate was added on day 4 to the suspension cultures of P. notoginseng cells. It was observed that, jasmonates greatly enhanced the ginsenoside content and the ratio of Rb group to Rg group (i.e. $(Rb_1\;+\;Rd)/(Rg_1\;+\;Re)$ in the P. notoginseng cells. Some of the synthetic jasmonates, such as pentafluoropropyl jasmonate (PFPJA), 2-hydroxyethyl jasmonate (HEJA) and 2-hydroxye-thoxyethyl jasmonate (HEEJA), could promote the ginsenoside content to $2.55\;\pm\;0.11,\;3.65\;\pm\;0.13\;and\;2.94\;\pm\;0.06$mg/100 mg DW, respectively, compared to that of $0.64\;\pm\;0.06$mg/100 mg DW for the control and $2.17\;\pm\;0.04$ mg/100 mg DW by the commercially available methyl jasmonate (MJA); and they could change the respective Rb:Rg ratio to $1.60\;\pm\;0.04,\;1.87\;\pm\;0.01\;and\;1.56\;\pm\;0.05$, compared to that of $0.47\;\pm\;0.01$ for the control and $1.42\;\pm\;0.06$ by MJA. The results suggest that suitable esterification of MJA with fluorine or hydroxyl group could in-crease the elicitation activity to induce plant secondary metabolism. The information obtained from this study is useful for hyper-production of heterogeneous products by plant cell cultures.

• Journal of Plant Biology
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• v.39 no.1
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• pp.63-69
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• 1996

A hairy root clone of Panax ginseng C.A. Meyer, HRB-15 was cultured iu various conditions with 3 L bubble type bioreactor to enhance both growth and ginsenoside production. The hairy roots were more rapidly grown under the dark condition than under the light condition. However, total amount of ginsenoside of hairy roots cultured under the light for 30 days increased 2 folds as compared with the dark condition and was 1.10% based on 6 ginsenosides. Especially, ginsenoside-Re was significantly increased and some ginsenosides except for ginsenoside-Re was slightly reduced. Also, the growth of hairy roots decreased about 30% as compared with the dark condition. In contrast, addition of sodium acetate led to decreased production of ginsenoside and growth of hairy roots under light condition. The influence of potassium dihydrogenphosphate concentration was examined in MS medium and a 1.25 mM concentration was found to be the most appropriate for growth and ginsenoside production under light condition. Two-step process of hairy roots culture with yeast elicitation or without ammonia in culture medium was developed to enhance growth and giusenoside synthesis. $50\;\mu\textrm{g}$ of yeast elicitor per g of fresh weight showed a synergistic effect on the ginsenoside synthesis of hairy roots on 20 days after culture. At that time, the content of total ginsenoside was 1.15%, while the growth of hairy roots decreased 21 % as compared with the dark condition. In addition, when elimination of ammonia on 20 days after culture, the content of total ginsenoside was 1.26% with significant increment of ginsenoside-Rd (0.27%) in addition to ginsenoside-Re and the growth of hairy roots decreased 10% as compared with the dark condition. In this system, we have demonstrated a unique two-step process of hairy root cultures to maximize biomass and secondary metabolites. It has found possibility to enhance ginsenosides production by growing hairy roots in this method.

• Journal of KIISE
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• v.44 no.3
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• pp.261-274
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• 2017

Variability management is the foremost criterion that defines the extent to which complexities can be handled in a system. Predominantly, the requirements' engineering (RE) study overlooks, or speculates a consistent behavior of, the environment in which a system functions. In real-time systems it is vital to observe and adjust to an intrinsically changing context. Therefore, in this work we identify the requirements of the system in various contexts by recommending a framework using i* goal model, problem frames, use case maps and live sequence charts. The framework is illustrated using a case study of the smart grid RTP system. In the case study, elaboration of scenarios using use case maps and live sequence charts proved beneficial as they assisted in early analysis and validation of contexts. In addition, the elaboration of requirements for obstacle and conflict analysis assists the requirements engineer to increase the robustness of the system. The proposed framework is evaluated theoretically and by empirical study.