• Proceedings of the KIEE Conference
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• 1996.07a
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• pp.585-587
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• 1996

A simple regenerative snubber structure is proposed, which is applicable to multi-level inverter with series-connected GTOs for high power applications. The novel snubber structure can solve large energy loss problems and guarantee safe operation of power converter can be achieved. The proposed new snubber has the potential of high performance and high reliability and is particularly suitable to high power and multi-level application with series connected power devices. The snubber voltage and current waveforms are analized and shown the simulation and experimental results for a GTO 3-level inverter circuit with inductive load.

• Natural Product Sciences
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• v.12 no.2
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• pp.109-112
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• 2006

The chloroform-soluble fraction of the vinegar treated small black soybean [Glycine max (Leguminosae)] showed antiproliferative activity against human myeloid leukemia HL-60 cells, in terms of inhibition of proliferation and induction of apoptosis. Bioassay-guided chromatography of the chloroform-soluble fraction resulted in the isolation of two isoflavonoid compounds, genistein and daidzein, as active principles. Genistein showed more potent antiproliferative effects against HL-60 cells. Treatment of HL-60 cells with genistein induced apoptosis in a dose dependent manner. Apoptosis was judged by the detection of DNA fragmentation by a flow cytometry and the degree of apoptosis was assayed by RT-PCR.

• Natural Product Sciences
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• v.12 no.4
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• pp.232-236
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• 2006

In this study, we investigated the effect of Phellinus baumii (PB) on immediate-type allergic reaction and inflammatory cytokine secretion. PB inhibited compound 48/80-induced systemic reactions in mice. PB inhibited compound 48/80-induced plasma histamine release. In addition, PB also inhibited the immunoglobulin (Ig) E-mediated local allergic reaction. Furthermore, PB decreased the phorbol 12-myristate 13-acetate plus calcium ionophore A23187-stimulated tumor necrosis $factor-\alpha$ and interleukin-6 secretion in human mast cells. These results indicate that PB may be beneficial in the treatment of immediate-type allergic reactions.

• Journal of Integrative Natural Science
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• v.11 no.2
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• pp.69-75
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• 2018

The red algae Gracilaria vermiculophylla is widely spread around seaside areas across the globe, and has been used as a food resource in Southeast Asian countries. Previous studies have shown that Gracilaria red algae extracts have beneficial antihypercholesterolemic, antioxidant, anti-inflammatory, and antimicrobial effects. In this study, we investigated the antioxidant effects of Gracilaria vermiculophylla extracts (GV-Ex) on human bone marrow mesenchymal stem cells (hBM-MSCs). The acetone and DMSO/ethanol solvents of the tested GV contain higher total flavonoid and polyphenolic contents that can strongly scavenge reactive oxygen species (ROS). Pre-treatment with GV-Ex protected hBM-MSCs against oxidative stress induced by hydrogen peroxide treatment. The protective effects of GV-Ex treatment were confirmed by MTT assay. The elevated levels of ROS in hBM-MSCs caused by hydrogen peroxide induced oxidative stress were significantly decreased by GV extract treatment. The levels of the antioxidant proteins superoxide dismutase 1 (SOD1), superoxide dismutase 2 (SOD2), and catalase (CAT) were also restored or protected by GV-Ex treatment, suggesting that GV extracts moderate excess ROS levels and prevent cells from oxidative damage.

• Journal of Microbiology and Biotechnology
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• v.29 no.2
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• pp.304-310
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• 2019

Interleukin-21 is a common ${\gamma}$-chain cytokine that controls the immune responses of B cells, T cells, and natural killer cells. Targeting IL-21 to strengthen the immune system is promising for the development of vaccines as well as anti-infection and anti-tumor therapies. However, the practical application of IL-21 is limited by the high production cost. In this study, we improved IL-21 production by codon optimization and selection of appropriate signal peptide in CHO-K1 cells. Codon-optimized or non-optimized human IL-21 was stably transfected into CHO-K1 cells. IL-21 expression was 10-fold higher for codon-optimized than non-optimized IL-21. We fused five different signal peptides to codon-optimized mature IL-21 and evaluated their effect on IL-21 production. The best result (a 3-fold increase) was obtained using a signal peptide derived from human azurocidin. Furthermore, codon-optimized IL-21 containing the azurocidin signal peptide promoted $IFN-{\gamma}$ secretion and STAT3 phosphorylation in NK-92 cells similar to codon-optimized IL-21 containing original signal peptide. Collectively, these results indicate that codon optimization and azurocidin signal peptides provide an efficient approach for the high-level production of IL-21 as a biopharmaceutical.

• Journal of Korean Medical classics
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• v.9
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• pp.381-429
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• 1996

Choo-Joo(鄒澍;1790-1844) was the medicine scholar who lived in the late peroid of the Chung-Dynasty and wrote "Bon-Kyung-So-Jeung(本經疏證)", "Bon-kyung-Sok-So(本經續疏)", "Bon-Kyng-Seo-So-Yo(本經序疏要)". In the books mentioned above, He annotated the chief effectiveness of herbal medicine(本草) which had been presented on "Shin-Nong-Bon-Cho-Kyung(神農本草經)" and "Myoung-Eui-Byul-Lok(名醫別錄)". He defined medical action of 315 herb-items with the many theories of various scholars. Scholars whom Choo-Joo has qoutated belong to the school of study of Chinese classics, and they have regarded "Hwang-Je-Nae-Kyung(黃帝內經)", "Shin-Nong-Bon-Cho-Kyung(神農本草經)" and "Sang-Han-Lon(傷寒論)" as great important cannon and have lived during the Myoung Chung Dynasty. The distinctive character of Choo-Joo belongs to similar academic traditions. It seems that he was appected mainly by "Bon-Cho-Gang-Mok(本草綱目)" written by Lee-Si-Jin(李時珍), Mok-Jung-Soon(繆仲淳)'s "Sin-Nonng-Bon-Cho-Kyung-So(神農本草經疏)", You-Yak-Guem(劉若金)'s "Bon-Cho-Sul(本草述)" and Yang-Si-Tae(楊時泰)'s "Bon-Cho-Sul-Gu-Won(本草述鉤元)". He contributed in two big sides. First, Choo-Joo(鄒澍) have achieved much contribution in biliographical study of Chinese classics(考證學). He analyzed the medical theory of herb-medicine, combining with "Nae-Kyung(內經)", "Sang-Han-Lon(傷寒論)" and many theory of various scholars in order to make research on the chief effectiveness that had been presented in "Shin-Nong-Bon-Cho-Kyung(神農本草經)". Therefore the practical application of medical theory and term which had been represented on classics were offered. Secondary, Choo-joo did great accomplishment in pharmacology. The point of his theory was grasping the effect of a medicine through distinctive one beyond general feature. He set up standards that grasp distintive feature as form, color, energy and taste, place of production and temper. And on the basis of these standards he investigated distinctive feature on various fields, then he induced 'the Uem-Yang-0-Haeng Theory(陰陽五行說)' from distictions. According to the these method of classification, form(形) stand for the resultant shape of herbal function, color(色) represent the active direction of herb, energy and taste(氣味) imply the ultimate active function of herb, the place of production(産地) and the period of occurrence(發生時期) symbolize symptoms. When he applied these method to seek for effetiveness, he regarded the field which revealed most representative feature as of great importance, and Combining remained distinctions with one another, he determined more accurate medicinal value. These method of obsevation solved contradiction which occured by equaly appling all medical herbs for the regular standard. The most important theory that represented in Choo-Joo(鄒澍) is to induce and to certify the distintive feature of herb into the 'Uem-Yang-0-Haeng Theory'. That is, concluded as "spring(生), growing(長), change(化), collecting(收) and storing(藏)". As the results of these studies, he made clear the action of medicine more concretly and made 'the Uem-Yang-0-Haeng Theory(陰陽五行說)' more concret and actual for applying. And he contrbuted to establish the standard for grasping the effect of medicines.

• Journal of the Korea Concrete Institute
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• v.26 no.1
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• pp.57-62
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• 2014

In this study, the vertical pipe cooling method was developed to propose the pipe cooling method suited for the vertically long mass concrete structures. FEM (finite element method) analysis was carried out to investigate the validity of the vertical pipe cooling method, and the temperature, the behavior of tensile stress of concrete and the crack index were investigated. In result, it was confirmed that the vertical pipe cooling method was effective in the thermal cracking control of mass concrete member.

• Journal of Genetic Medicine
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• v.9 no.2
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• pp.89-92
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• 2012

Campomelic dysplasia (CMD) is a rare, often lethal, genetic disorder characterized by multiple congenital anomalies and abnormal development of the reproductive organs in males. Mutations in the SOX9 gene are known to cause CMD. We present a Korean CMD girl with a normal 46,XX karyotype and a female reproductive organ phenotype. She was born at 2.35 kg at 38 weeks of gestation and showed characteristic phenotypes, including cleft palate, micrognathia, hypertelorism, flat nasal bridge, congenital bowing of limbs, hypoplastic scapulae, deformed pelvis, and 11 pairs of ribs. She also had an atrioseptal defect of the heart and marked laryngotracheomalacia requiring tracheostomy and tracheopexy. SOX9 mutation analysis revealed the presence of a novel nonsense mutation, $p.Gln369^*$, and the patient was genetically confirmed to have CMD. Although she showed marked failure to thrive and neurodevelopmental delay, she is now 40 months of age and is the only surviving patient with CMD in Korea.

• Proceedings of the KSME Conference
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• 2001.06d
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• pp.612-617
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• 2001

This paper reports the cooling performance of a PDP(plasma display panel) with a heat spreader by means of numerical analysis. Due to the simplifications and assumptions inherent in the analysis, computed results are found to differ those of the experiment by 13%. Calculation shows a maximum temperature of $65^{\circ}C$ for the plasma glass, as opposed to the allowable temperature of $90^{\circ}C$, producing a temperature difference of $25^{\circ}C$ between the upper and lower regions. This is enough to cause cracks in the plasma glass. In order to avoid this, more ventholes are added at the upper center region of the back cover, thereby causing a $3^{\circ}C$ drop in the maximum temperature, which reduces the temperature difference to $12^{\circ}C$. The new design gives more uniform temperature distribution across the plasma glass.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.43 no.4
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• pp.199-204
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• 1998

This study was conducted to investigate the chromosomal locations and effects of quantitative trait loci (QTL) associated with chemical properties of rice (Oryza sativa L.). One hundred sixty four recombinant inbred lines (MGRILs) of $F_{11}$ were derived from the cross between Milyang 23, Tongil type, and Gihobyeo, japonica type. They were evaluated for 7 traits of chemical property in rice. Transgressive segregation was observed for all traits examined. Eight significant QTLs were detected (LOD$\geq$2.0) for five traits, including two QTLs for amylose content, two QTLs for potassium content, one QTL for ratio of magnesium to potassium, one QTL for fat content and two QTLs for ash content. Phenotypic variation explained by each QTL ranged from 7.2% to 14.4%. However, no significant QTL was detected for magnesium and protein contents. In amylose content and ash content M alleles originated from Milyang 23 were responsible for increasing these traits and J alleles originated from Gihobyeo also responsible for increasing these traits. Pleiotropic effects of single QTLs on different traits are observed.