• Applied Biological Chemistry
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• v.37 no.3
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• pp.189-193
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• 1994

The hydrolysis of fungicidal N-[1-(benzotriazol-1-yl)benzyl]aniline (BBA) molecule in the presence of cationic cetyltrimethylammonium bromide (CTABr) and anionic sodium laurylsulfate (NaLs) micellar solutions has been studied kinetically. The Micellar catalysis effect shows that the rate is slightly accelerated by the addition of the anionic NaLs at high pH and the binding constant (Ks) is $1.45{\times}10^4M^{-1}$. This result presumably is due to the electrostatic stabilization by the anionic micelle of the developing carbocation in the transition state rather than the hydrophobic character (${\pi}$: 4.93) of (BBA).

• Microbiology and Biotechnology Letters
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• v.24 no.4
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• pp.485-492
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• 1996

myo-Inositol, a growth factor for Saccharomyces cerevisiae (S. cerevisiae), has been known to be incorporated into phosphatidylinositol (PI), which is a kind of phospholipid in the cell membrane, by a membrane-associated PI-synthesizing enzyme. The deficiency of myo-inositol in S. cerevisiae adversely affected the membrane structure and function. On the basis of biochemical functions of myo-inositol, the effect of deficiency of myo-inositol on the aerobic glucose metabolism was investigated by measuring specific oxygen uptake rate (Q$_{O2}$) used as an indicator representing the respiratory capacity of S. cerevisiae in batch and continuous cultures. The respiratory capacity of aerobic glucose metabolism in S. cerevisiae was also monitored after glucose pulse-addition in a continuous culture (D=0.2, 1/hr), in which glucose was utilized through respiratory metabolism. The deficiency of myo-inositol was found to lead to both the decrease of the maximum specific oxygen uptake rate (Q$_{O2max}$) observed from the batch as well as in the continuous culture experiment and the decrease of the respiratory capacity of aerobic glucose metabolism of S. cerevisiae determined from the glucose pulse-addition experiment, in which the glucose flux into respiratory and fermen- tative metabolism was quantitatively analyzed.

• Journal of Microbiology and Biotechnology
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• v.28 no.8
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• pp.1310-1317
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• 2018

The stems of Dendrobium moniliforme have been used in traditional herbal medicine for the treatment of fever and lack of body fluid in Korea. In this study, we investigated anti-inflammatory effects of the aqueous extract of D. moniliforme stems (DM) in response to lipoteichoic acid (LTA), a major constituent of the cell wall of Gram-positive bacteria. DM inhibited LTA-induced expression of a pro-inflammatory mediator inducible nitric oxide synthase (iNOS) in the murine macrophages. And DM induced expression of heme oxygenase-1 (HO-1) at the transcriptional level. Conversely, the knockdown of HO-1 expression by siRNA markedly reversed the inhibitory effects of DM on LTA-induced iNOS expression. We also demonstrated that nuclear translocation of Nrf2 was increased following treatment with DM. In addition, DM-mediated Nrf2 activation and HO-1 expression were suppressed by PI3K/Akt and p38 inhibitors; treatment with DM also resulted in phosphorylation of Akt and p38. These results suggest that DM inhibits the expression of iNOS in LTA-stimulated macrophages, and that these effects are mediated by the upregulation of HO-1 expression via PI3K/Akt/p38-Nrf2 signaling.

• Journal of the Optical Society of Korea
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• v.18 no.1
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• pp.37-44
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• 2014

The use of a laser interferometer as a metrological tool in micro-optics measurement is demonstrated. A transmissive interferometer is effective in measuring an optical specimen having a high angle slope. A configuration that consists of an optical resolution of 0.62 micron is adapted to measure a specimen, which is a micro-Fresnel lens-shaped lenticular lens. The measurement result shows a good repeatability at each fraction of facets, however, a reconstruction of the lens shape profile is disturbed by a known problem of $2{\pi}$-ambiguity. To solve this $2{\pi}$-ambiguity problem, we propose a two-step phase unwrapping method. In the first step, an unwrapped phase map is obtained by using a conventional unwrapping method. Then, a proposed unwrapping method based on the shape modeling is applied to correct the wrongly unwrapped phase. A measured height of each facet is compared with a profile result measured by AFM.

• Journal of Power Electronics
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• v.17 no.6
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• pp.1500-1511
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• 2017

The purpose of this paper is to study a high-performance control scheme for neutral-point-clamping three-level (NPC-3L) inverter fed dual three-phase permanent magnet synchronous motor (PMSM) drives by considering some asymmetric factors such as the non-identical parameters in phase windings. To implement this, the system model is analyzed for dual three-phase PMSM drives with asymmetric factors based on the vector space decomposition (VSD) principle. Based on the equivalent circuits, PI controllers with feedforward compensation are used in the d-q subspace for regulating torque, where the cut-off frequency of the PI controllers are set at the twice the fundamental frequency for compensating both the additional DC component and the second order component caused by asymmetry. Meanwhile, proportional resonant (PR) controllers are proposed in the x-y subspace for suppressing the possible unbalanced currents in the phase windings. A dual three-phase space vector modulation (DT-SVM) is designed for the drive, and the balancing factor is designed based on the numerical fitting surface for balancing the DC link capacitor voltages. Experimental results are given to demonstrate the validity of the theoretical analysis and the proposed control scheme.

• Bulletin of the Korean Chemical Society
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• v.14 no.5
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• pp.546-548
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• 1993

The discrete structure of substituted 9-benzonorbornenyl cation 3a and 3c was studied using the empirical ${\Delta}$J equation which was developed by Kelly and coworker$^5$. The ${\Delta}$J values of substituted 9-benzonorbornenyl cations were obtained from p-methyl-6,7-dimethyl benzonorbornen-9-yl (3a) and 9-methyl-6,7-dimethyl benzonorbonen-9-yl (3c) cations under stable ion conditions, and were compared with those of the corresponding ketone analog; these cations were generated by dissolving the corresponding carbinols in superacid at -120$^{\circ}$C and the nmr spectra taken at -60$^{\circ}$C~-90$^{\circ}$C. The ${\Delta}$J values are 8.7 Hz for the bridgehead carbons in cation 3c and 3.1 Hz for cation 3b. The ${\Delta}$J values at C5,8 in fused benzene ring are 14.3 Hz for cation 3c and 8.7 Hz for cation 3a. The excellent correlation of the ${\Delta}$J values with 1$^9F$ chemical shifts of p-fluorophenyl-6,7-dimethylbenzonorbornenyl cation (3d) indicate that ${\Delta}$J value is a reliable probe to charge density at adjacent cationic carbon. These NMR parameters strongly support that the symmetrically ${\pi}$-bridged nonclassical structure (type 2) of substituted 9-benzonorbornenyl cations in stable ion conditions.

• Fisheries and Aquatic Sciences
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• v.24 no.1
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• pp.1-9
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• 2021

Human prostate cancer is the second most frequently diagnosed cancer worldwide, and its incidence rate continues to increase. Advanced prostate cancer is more difficult to treat than early forms due to its chemotherapy resistance. There is need for more effective agents that can inhibit the progression of advanced prostate cancer. Demethoxyfumitremorgin C (DMFTC) was isolated from the fermentation extract of the marine fungus Aspergillus fumigatus. Antiproliferative activity of DMFTC against human prostate cancer PC3 cells was examined through cell cycle analysis by flow cytometry, the fluorescent nuclear imaging analysis with propidium iodide (PI), and proteins expression related to cell cycle arrest and apoptosis were investigated via Western blotting. DMFTC inhibited PC3 cells growth through G1 phase cell cycle arrest and apoptosis induction. It activated the tumor suppressor p53 and the Cdk inhibitor p21, which regulate the cell progression into the G1 phase. Additionally, PI-positive late apoptotic non-viable cells were increased and the expression levels of the G1-positive downstream regulators cyclin D, cyclin E, Cdk2, and Cdk4 were decreased by DMFTC treatment. These results suggest that DMFTC induces G1 arrest and apoptosis induction through regulation of p53/p21-dependent cyclin-Cdk complexes, and it may be a useful therapeutic agent for the treatment of human advanced prostate cancer.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.35 no.5
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• pp.509-515
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• 2022

As the 4th industrial revolution based on ICT is progressing in the manufacturing field, interest in building smart factories that can be flexible and customized according to customer demand is increasing. To this end, it is necessary to maximize the efficiency of factory by performing an automated process in real time through a network communication between engineers and equipment to be able to link the established IT system. It is also necessary to collect and store real-time data from heterogeneous facilities and to analyze and visualize a vast amount of data to utilize necessary information. Therefore, in this study, four types of controllers such as PLC, Arduino, Raspberry Pi, and embedded system, which are generally used to build a smart factory that can connect technologies such as artificial intelligence (AI), Internet of Things (IoT), and big data, are configured. This study was conducted for the development of a program that can collect and store data in real time to visualize and manage information. For communication verification by controller, data communication was implemented and verified with the data log in the program, and 3D monitoring was implemented and verified to check the process status such as planned quantity for each controller, actual quantity, production progress, operation rate, and defect rate.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2022.09a
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• pp.87-87
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• 2022

Under the COVID-19 pandemic, interest in immune enhancement and anti-obesity is increasing. Thus, in this study, we investigated whether Kadsura japonica fruits (KJF) exhibits immunostimulatory activity and anti-obesity activity. KJF increased the production of immunostimulatory factors and phagocytosis in RAW264.7 cells. Inhibition of TLR2 and TLR4 blocked KJF-mediated production of immunostimulatory factors in RAW264.7 cells. In addition, the inhibition of MAPK and PI3K/AKT signaling pathway reduced KJF-mediated production of immunostimulatory factors, and the activation of MAPK and PI3K/AKT signaling pathway by KJF suppressed the inhibition of TLR2/4. KJF attenuated the lipid accumulation and the protein expression such as CEBPα, PPARγ, perilipin-1, adiponectin, and FABP4 related to the lipid accumulation in 3T3-L1 cells. In addition, KJF inhibited excessive proliferation of 3T3-L1 cells and protein expressions such as β-catenin and cyclin D1 related to cell growth. These findings indicate that KJF may have immunostimulatory activity and anti-obesity activity.

• The Transactions of the Korean Institute of Power Electronics
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• v.7 no.2
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• pp.205-213
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• 2002

This paper deals with the implementation of three-phase VSI systems which can control the power regenerated from DC bus line to AC supply. The overall system consists of the line-to-line voltage and line current sensors, an actual power calculator using d-q transformation method, a complex power controller with PI control scheme, a gating signal generator for modified ｑ-conduction mode, a DPLL for frequency followup, and Power circuits. Control board is constructed by using a 32-bit DSP TMS32C32, two EFLDs , six ADCs, and a DAC. To verify the performance of the proposed system, we designed and constructed the propotype with the power rating of 5kVA at AC 220V. Experimental results show that the regenerated active power is well controlled to its command vague and the regenerated reactive power still remained at nearly zero through all operating modes.