• Journal of Plant Biotechnology
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• v.6 no.2
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• pp.97-102
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• 2004

This study was carried out to establish The regeneration of healthy seedlings from the nodal segment culture of Chinese yam (Dioscorea opposita cv. Danma), cultivated in Korea. Different explants such as leaves, petioles, roots and nodal pieces, excised from the in vitro grown seedlings of Chinese yam, were cultured on MS medium supplemented with various combinations of growth regulators. All the growth regulators used induced plantlet regeneration from the nodal segments at a high frequency, while there was no induction of shoot or callus from leaf, petiole or root tissues. The medium supplemented with 0.01mg/L NAA, 0.5mg/L BA, 0.5-1.0mg/L kinetin and without plant growth regulator was effective for shoot development of buds from the nodal segment culture. The concentration of BA and NAA was an important factor in the bud induction of buds from the nodal segments of Chinese yam. Nodal segments cultured on the medium containing 1.0mg/L NAA and 0.5-1.0mg/L BA gave the best response to bud formation. The addition of GA$_3$ to the culture medium suppressed shoot induction and growth, while it increased microtuber formation. The shoot growth and microtuber formation were also affected by medium strength and solidity. The MS basal medium containing 1 g/L gelrite was suitable for microtuber formation from the nodal segment of Chinese yam.

• Molecules and Cells
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• v.37 no.12
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• pp.907-911
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• 2014

The function of reactive oxygen species (ROS) as second messengers in cell differentiation has been demonstrated only for a limited number of cell types. Here, we used a well-established protocol for BMP2-induced neuronal differentiation of neural crest stem cells (NCSCs) to examine the function of BMP2-induced ROS during the process. We first show that BMP2 indeed induces ROS generation in NCSCs and that blocking ROS generation by pretreatment of cells with diphenyleneiodonium (DPI) as NADPH oxidase (Nox) inhibitor inhibits neuronal differentiation. Among the ROS-generating Nox isozymes, only Nox4 was expressed at a detectable level in NCSCs. Nox4 appears to be critical for survival of NCSCs at least in vitro as down-regulation by RNA interference led to apoptotic response from NCSCs. Interestingly, development of neural crest-derived peripheral neural structures in Nox4-/- mouse appears to be grossly normal, although Nox4-/- embryos were born at a sub-Mendelian ratio and showed delayed over-all development. Specifically, cranial and dorsal root ganglia, derived from NCSCs, were clearly present in Nox4-/- embryo at embryonic days (E) 9.5 and 10.5. These results suggest that Nox4-mediated ROS generation likely plays important role in fate determination and differentiation of NCSCs, but other Nox isozymes play redundant function during embryogenesis.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.39 no.1
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• pp.25-30
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• 2016

It is critical to forecast the maximum daily and monthly demand for power with as little error as possible for our industry and national economy. In general, long-term forecasting of power demand has been studied from both the consumer's perspective and an econometrics model in the form of a generalized linear model with predictors. Time series techniques are used for short-term forecasting with no predictors as predictors must be predicted prior to forecasting response variables and containing estimation errors during this process is inevitable. In previous researches, seasonal exponential smoothing method, SARMA (Seasonal Auto Regressive Moving Average) with consideration to weekly pattern Neuron-Fuzzy model, SVR (Support Vector Regression) model with predictors explored through machine learning, and K-means clustering technique in the various approaches have been applied to short-term power supply forecasting. In this paper, SARMA and intervention model are fitted to forecast the maximum power load daily, weekly, and monthly by using the empirical data from 2011 through 2013. $ARMA(2,\;1,\;2)(1,\;1,\;1)_7$ and $ARMA(0,\;1,\;1)(1,\;1,\;0)_{12}$ are fitted respectively to the daily and monthly power demand, but the weekly power demand is not fitted by AREA because of unit root series. In our fitted intervention model, the factors of long holidays, summer and winter are significant in the form of indicator function. The SARMA with MAPE (Mean Absolute Percentage Error) of 2.45% and intervention model with MAPE of 2.44% are more efficient than the present seasonal exponential smoothing with MAPE of about 4%. Although the dynamic repression model with the predictors of humidity, temperature, and seasonal dummies was applied to foretaste the daily power demand, it lead to a high MAPE of 3.5% even though it has estimation error of predictors.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.149-149
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• 2017

The RING (Really Interesting New Gene) finger proteins are known to play crucial roles in various abiotic stresses in plants. In this study, we report on RING finger E3 ligase, ${\underline{O}ryza}$ ${\underline{s}ativa}$ ${\underline{s}alt$-, ${\underline{A}BA}$- and ${\underline{d}rounght}$ stress-${\underline{i}nduced}$ RING finger ${\underline{p}}rotein{\underline{1}}$ gene (OsSAD1). In vitro ubiquitination assay demonstrated that unlike OsSAD1, a single amino acid substitution ($OsSAD1^{C168A}$) of the RING domain showed no E3 ligase activity, supporting the notion that the activity of most E3s is specified by a RING domain. Result of Yeast-Two hybridization, In vivo protein degradation assay supports that OsSAD1 interacting with 3 substrate, OsSNAC2, OsGRAS44 and OsPIRIN1, and mediates proteolysis of 3 substrates via the 26S proteasome pathway. Subcellular localizations of OsSAD1 while approximately 62% of transient signals were detected in cytosol, 38% of signals were showed nucleus. However, transiently expression of OsSAD1 was detected in cytosol 30% while as 70% of nucleus under 200 mM salt treated rice protoplasts. Results of bimolecular fluorescence complementation (BiFC) showed that two nucleus-localized proteins (OsSNAC2 and OsGRAS44) interacted with OsSAD1 in the both cytosol and nucleus. Heterogeneous overexpression of OsSAD1 Heterogeneous overexpresssion of OsSAD1 in Arabidopsis exhibited sensitive phenotypes with respect to Salt-, mannitol-responsive seed germination, seedling growth. In ABA conditions, OsSAD1 overexpression plants showed highly tolerance phenotypes, such as root length and stomatal closure. Our findings suggest that the OsSAD1 may play a negative regulator in salt stress response by modulating levels of its target proteins.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.130-130
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• 2017

Sorghum bicolor is considered as copper-tolerant species. The present study was conducted to understand the copper tolerance mechanism in Sorghum seedling roots. Morphological and effects of Cu on other interacting ions were observed prominently in the roots when the plants were subjected to different concentrations (0, 50, and $100{\mu}M$) of $CuSO_4$. However, the morphological characteristics were reduced by Cu stress, and the most significant growth inhibition was observed in plants treated with the highest concentration of $Cu^{2+}$ ions ($100{\mu}M$). In the proteome analysis, high-throughput two-dimensional polyacrylamide gel electrophoresis coupled with MALDI-TOF-TOF mass spectrometry was performed to explore the molecular responses of Cu-induced sorghum seedling roots. In two-dimensional silver-stained gels, a total of 422 differentially expressed proteins (${\geq}1.5-fold$) were identified using Progenesis SameSpot software. A total of 21 protein spots (${\geq}1.5-fold$) from Cu-induced sorghum roots were analyzed by mass spectrometry. Of the 21 differentially expressed protein spots from Cu-induced sorghum roots, a total of 10 proteins were up-regulated, and 11 proteins were down-regulated. The abundance of the most identified protein species from the roots that function in stress response and metabolism was significantly enhanced, while protein species involved in transcription and regulation were severely reduced. The results obtained from the present study may provide insights into the tolerance mechanism of seedling roots in Sorghum.

• Korean Journal of Pharmacognosy
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• v.2 no.1
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• pp.23-28
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• 1971

This study was planned to see whether the Panax Ginseng root has any influence upon the emotionality in rats exposed to a novel open-field and induced by a grid shock. Sixty four male albino rats whose body weight ranged from 130 to 180 gm were used. They were divided into four groups, i.e., placebo control group, 5mg/kg Ginseng ext. group, 10mg/kg Ginseng ext. group, and 20mg/kg Ginseng ext. group. Sixteen rats were subjected in each group. Open-field activity was measured in a $2.20m\;{\times}\;2.20m$ open-field that was divided into 15cm squares. Four novel objects and food pellets were put with an equal distance in the open-field. Locomotion was recorded by entering the number of squares traversed for 4 min. and behaviors which were shown at the 10-sec. period were checked by a modified Jarrad and Bunnel's observation procedure. Sensitivity to the grid shock was measured in a compartment of shuttle box. 10, 20, 30, 40, 50, 60 and 70 volt ac. 2 sec., electric shock were delivered in each subject by the grid to animal's feet. Flinch, vocalization and jumping responses were rated in each shock level. The results obtained were as follows: 1.) 5mg/kg and 10mg/kg Ginseng ext. groups were tended to increase the ambulation and exploration compared with placebo control. 2.) All Ginseng extract groups were defecated significantly less often than placebo control in the open-field and shock situation. 3.) Thresholds to the electric shock were tended to elevate in all Ginseng groups. 4.) These results suggest that Ginseng extract has a stimulant action in open-field and a tranqulizing action in feared situation.

• Korean Journal of Veterinary Research
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• v.34 no.4
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• pp.769-779
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• 1994

The root of Bupleurum falcatum L.(BF) has been widely used in oriental medicine as a major camponent in many prescriptions for chronic hepatitis, renal disease, tuberculosis and some other infectious diseases. Many attempts have done to investigate the therapeutic effects of these principles. However, any kinds of screenig on immune regulatory- and antitumor- effects of BF has not been reported. The present study, therefore, was undertaken to investigate the BF-effects on cellular- and humoral-immune responses, phagocytic activities of macrophages, lymphokine- and Immunoglobulin(Ig)-production of lymphocytes, tumorigenesis of implanted sarcoma 180 cells and B16 melanoma cells, and proliferations of some tumor cell lines(Fsa II, 3LL and EL4). BF increased phagocytic activities of mouse peritoneal macrophages in a dose- and time-dependent fashion. Arthus reaction and antibody responses to SRBC were slightly enhanced but delayed hypersensitivity was depresed when BF was injected before- and after-SRBC sensitization. BF inhibited the proliferative responses of human tonsillar lymphocytes to PHA- and Con A-stimulation but slightly augmented the response of these cells to Staphylococcus aureus Cowan 1(SAC)-activation. Ig secretion of human mononuclear cells activated with SAC was slightly increased by BF. BF significantly augmented the SAC-induced IL 6 production of human mononuclear cells but not influenced Con Ainduced IL 2 secretion. NK cell activities of mouse splenocytes were somewhat increased when BF was pretreated and this responses were due to the increment of binding affinities of effector cells to target cells and of lytic activities of effector cells against target cells. In vitro BF significantly inhibited the proliferations of cancer cells such as Fsa II, 3LL and EL4 strains. BF decreased not only the frequency of tumor induction but also the tumor size per sarcoma 180 or B16 cell-implanted mouse. Taken together, these results indicate that BF is one of the potential immunomodulator, and suggest its possibility to be used as a desirable antitumor agent.

• Journal of Korean Society on Water Environment
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• v.33 no.4
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• pp.387-393
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• 2017

A chemical batch tests were conducted to evaluate if microwave heating enhances phosphorous release from waste activated sludge (WAS) at pH 2.5, 5, 7, 9 and 11. Polyphosphate-accumulating organisms have a unique physiological feature, which releases intracellular polyphosphate granules when they are exposed under high temperature environments. Microwave irradiation was found to encourage large amount of phosphorus release from WAS, depending on pH and temperature conditions. Most of phosphorus was released below $59^{\circ}C$ within 30 min. A marked increase in phosphorus release was observed under alkaline or acidic conditions. However, based on control tests for phosphorus release under different pH conditions without microwave heating, the largest amount of phosphorus released by microwave irradiation was found at pH 7, followed by 5, 9, 11. On the other hand, crystallization was conducted to obtain magnesium ammonium phosphate (MAP) from phosphate released by microwave heating at pH 7. X-ray diffraction analysis confirmed that the recovered crystalline materials were MAP. MAP is an environmentally friendly fertilizer, which slowly releases ammonia and phosphorus in response to the demand of plant root. Thus, the recovered MAP as a phosphate fertilizer is fully expected to play a important role in the reduction of agricultural non-point pollution.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.29 no.10
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• pp.601-607
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• 2016

Piezoelectric thick films of soft $Pb(Zr,Ti)O_3$ (PZT) based commercial material (S55) were fabricated using a conventional tape casting method. Ag-Pd electrodes were printed on the piezoelectric film at room temperature and all 5 layered films with a dimension of $12mm{\times}16mm$ were successfully laminated for a multi-layered piezoelectric ceramic actuator. The laminated specimens were co-fired at $1,100^{\circ}C$ for 1 h. A flat layered and dense microstructure was obtained for the $112{\mu}m$ thick piezoelectric actuator after sintering process. Thereafter, a prototype piezoelectric speaker was fabricated using the multi-layered piezoelectric ceramic actuator which can operate as a bimorph. Its SPL (sound pressure level) characteristic was also evaluated for speaker application. Frequency response revealed that the output SPL with a root mean square voltage of 10 V increased gradually to the highest peak of 87.5 dB for 1.5 kHz and exhibited a relatively stable behavior over the measured frequency range (${\leq}20kHz$) at a distance of 10 cm, implying that the fabricated piezoelectric speaker is potential for speaker applications.

• Computers and Concrete
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• v.20 no.5
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• pp.545-553
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• 2017

A pounding tuned mass damper (PTMD) can be considered as a passive device, which combines the merits of a traditional tuned mass damper (TMD) and a collision damper. A recent analytical study by the authors demonstrated that the PTMD base on the energy dissipation during impact is able to achieve better control effectiveness over the traditional TMD. In this paper, a PTMD prototype is manufactured and applied for seismic response reduction to examine its efficacy. A series of shaking table tests is conducted in a three-story building frame model under single-dimensional and two-dimensional broadband earthquake excitations with different excitation intensities. The ability of the PTMD to reduce the structural responses is experimentally investigated. The results show that the traditional TMD is sensitive to input excitations, while the PTMD mostly has improved control performance over the TMD to remarkably reduce both the peak and root-mean-square (RMS) structural responses under single-dimensional earthquake excitation. Unlike the TMD, the PTMD is found to have the merit of maintaining a stable performance when subjected to different earthquake loadings. In addition, it is also indicated that the performance of the PTMD can be enhanced by adjusting the initial gap value, and the control effectiveness improves with the increasing excitation intensity. Under two-dimensional earthquake inputs, the PTMD controls remain outperform the TMD controls; however, the oscillation of the added mass is observed during the test, which may induce torsional vibration modes of the structure, and hence, result in poor control performance especially after a strong earthquake period.