• Mycobiology
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• v.50 no.6
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• pp.457-466
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• 2022

Epicoccum nigrum is a saprophytic or endophytic fungus that is found worldwide. Because of the antagonist effects of E. nigrum on many plant pathogens, current studies on E. nigrum have focused on the development of biological control agents and the utilization of its various metabolites. In this study, E. nigrum was collected from a wheat field, and its genetic diversity was analyzed. Phylogenetic analyses identified 63 isolates of E. nigrum divided into seven groups, indicating a wide genetic diversity. Isolates antagonized the wheat pathogen Fusarium graminearum, and reduced disease symptoms caused by F. graminearum in wheat coleoptiles. Moreover, pretreatment of wheat coleoptiles with E. nigrum induced the upregulation of pathogen-related (PR) genes, PR1, PR2, PR3, PR5, PR9, and PR10 in wheat coleoptiles responding to F. graminearum invasion. Overall, this study indicates that E. nigrum isolates can be used as biological pathogen inhibitors applied in wheat fields.

• Journal of Haehwa Medicine
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• v.10 no.1
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• pp.109-114
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• 2001

To evaluate the antitumor activity of Paridis Rhizoma(PR), studies were done experimentally. The results were obtained as follows: 1. In cytotoxicity against MCF-7, SK-OV-3, HCT15, concentration inhibiting cell growth up to below 50% of control was recognized at $100-200{\mu}g/m{\ell}$ of PR and also against A549, XF498 was recognized at $50-100{\mu}g/m{\ell}$. 2. In Inhibitory effect on activity of DNA topoisomerase I, the $IC_{50}$ was shown $50-100{\mu}g/m{\ell}$ of PR. 3. The concentration inhibiting adhesion of A549 and SK-OV-3 to complex extracellular matrix up to below 50% of control was recognized at $10-100{\mu}g/m{\ell}$ of PR. 4. The T/C% was 137.9 in PR-treated group in S-180 bearing ICR mice. From above results it was concluded that PR could be usefully applied for the prevention and treatment of cancer.

• Korean Journal of Oriental Medicine
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• v.15 no.3
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• pp.99-105
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• 2009

In this research, the genotoxic effects of Pinelliae Rhizoma (PR) extracts, one of famous herbal agents in Korean medicine were evaluated using the mouse micronucleus test. PR extracts was administered once a day for 2 continuous days by oral gavage to male ICR mice at doses of 2000, 1000, and 500 mg/kg. Cyclophosphamide was used as a known genotoxic agent in a positive control. The appearance of a micronucleus is used as an index for genotoxic potential. No PR extracts treatment-related abnormal clinical signs, body weight changes and mortalities were detected. Significant (p<0.01) increases of the numbers of polychromatic erythrocytes contain micronucleus in prepared bone marrow cells were detected in CPA and PR extracts 2000 mg/kg treated groups as compared with intact control, respectively. The results of intraperitoneal dose mouse bone marrow cell micronucleus test of PR extracts were positive in the present study. It is considered that there were no problems from cytotoxicity of PR extracts tested in this study because the polychromatic erythrocyte ratio was detected as > 0.42 in all tested groups.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.21 no.2
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• pp.311-315
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• 2012

Diaphragm type noncontact automatic control valve is a valve for controling acidic PR(Photo Resist) liquid used in the semiconductor process. PR is photosensitive liquid that changes phases depending on light transmittance. PR is very toxic and expensive; the purpose of this paper is to address methods that prevent loss due to leaks. The design of noncontact precise automatic control valve is expected to play an important role in controlling fluid flow, therefore influencing energy conservation and environmental improvement. In this paper, diaphragm type automatic control valve's part design, assembly and simulation are introduced. Also, through the analysis of fluid flow the valve's internal velocity, pressure, and turbulent intensity are interpreted. This paper proposes to contribute to the improvement of the valve's performance.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.21 no.10
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• pp.1619-1625
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• 1997

This paper concerns a 2-axis PR type pneumatic manipulator system translating in vertical and rotating in horizontal directions. A simplified linear model is mathematically formulated similar to the pneumatic acturators in dynamic responses in order to devise an appropriate position control scheme. A PD controller preceding the on/off solenoid valve turns out not only economical but also effective in reducing rise time and amplitude of limit cycles, if its control gains are determined on the basis of frequency response. And, additional implementation of symmetric or asymmetric deadband at the PD controller output greatly helps minimize valve opening numbers, positional error, and undesirable direction-dependent property due to the gravitational load. Such a control concept is synthesized through numerical simulations and next applied to the experimental set-up, featuring enhanced positional servo characteristics.

• Journal of Ginseng Research
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• v.39 no.4
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• pp.406-413
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• 2015

Background: Pathogenesis-related 10 (PR-10) proteins are small, cytosolic proteins with a similar three-dimensional structure. Crystal structures for several PR-10 homologs have similar overall folding patterns, with an unusually large internal cavity that is a binding site for biologically important molecules. Although structural information on PR-10 proteins is substantial, understanding of their biological function remains limited. Here, we showed that one of the PgPR-10 homologs, PgPR-10.3, shares binding properties with flavonoids, kinetin, emodin, deoxycholic acid, and ginsenoside Re (1 of the steroid glycosides). Methods: Gene expression patterns of PgPR-10.3 were analyzed by quantitative real-time PCR. The three-dimensional structure of PgPR-10 proteins was visualized by homology modeling, and docking to retrieve biologically active molecules was performed using AutoDock4 program. Results: Transcript levels of PgPR-10.3 expressed in leaves, stems, and roots of 3-wk-old ginseng plantlets were on average 86-fold lower than those of PgPR-10.2. In mature 2-yr-old ginseng plants, the mRNA of PgPR-10.3 is restricted to leaves. Ginsenoside Re production is especially prominent in leaves of Panax ginseng Meyer, and the binding property of PgPR-10.3 with ginsenoside Re suggests that this protein has an important role in the control of secondary metabolism. Conclusion: Although ginseng PR-10.3 gene is expressed in all organs of 3-wk-old plantlets, its expression is restricted to leaves in mature 2-yr-old ginseng plants. The putative binding property of PgPR-10.3 with Re is intriguing. Further verification of binding affinity with other biologically important molecules in the large hydrophobic cavity of PgPR-10.3 may provide an insight into the biological features of PR-10 proteins.

• Proceedings of the Korean Information Science Society Conference
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• 2002.04b
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• pp.277-279
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• 2002

본 논문에서는 온라인 컴퓨터 게임에서 지능형 NPC가 수행할 수 있는 역할과 이러한 지능형 NPC를 구현하기 위해 요구되는 제어구조의 특성을 살펴본다. 그리고 종래에 사용되던 NPC 제어 방법들과 이들이 갖는 문제점들을 살펴보고 새로운 대안으로서 NPC 제어를 위해 UH-PRS의 적용을 제안한다. 따라서 본 논문에서는 UM-PRS에 대한 간략한 소개와 NPC 제어구조에 적합한 UM-PRS의 특성을 설명한다. 또 본 논문에서는 대표적인 롤플레잉(role-playing) 게임인 Ultima Online에 서 개발중인 Umtimabot의 설계를 통해 U7-PRS의 적용가능성과 효과를 알아본다.

• Proceedings of the Korea Society for Simulation Conference
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• 1999.10a
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• pp.62-62
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• 1999

In this paper, we propose a new technique of estimating tail of steady-state queue length distribution; Pr(Q>q), fo ATM multiplexer. Pr(Q>q) is a fundamental measure of network congestion. Assessing Pr(Q>q) properly is crucial for design and control of ATM networks. Data traffic pattern of high-speed networks is highly correlated and bursty. Estimating Pr(Q>q) is very difficult because of correlation and burstiness. We estimate entropy(rate-function) using large deviation principles and threshold bootstrap. Simulation studies are conducted to compare the performance of an existing method and our new method.

• Journal of Microbiology and Biotechnology
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• v.28 no.10
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• pp.1749-1759
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• 2018

Recombinant (rec) prion protein (PrP) is an extremely useful resource for studying protein misfolding and subsequent protein aggregation events. Here, we report mass production of high-purity rec-polypeptide encoding the C-terminal globular domain of PrP; (90-230) for human and (89-231) for murine PrP. These proteins were expressed as His-tagged fusion proteins in E. coli cultured by a high cell-density aerobic fermentation method. RecPrPs recovered from inclusion bodies were slowly refolded under reducing conditions. Purification was performed by a sequence of metal-affinity, cation-exchange, and reverse-phase chromatography. The current procedure yielded several dozens of milligrams of recPrP per liter with >95% purity. The purified recPrPs predominantly adopted an ${\alpha}$-helix-rich conformation and were functionally sufficient as substrates to measure the seeding activity of human and animal prions. Establishment of a procedure for high-level production of high-purity recPrP supports the advancement of in vitro investigations of PrP including diagnosis for prion diseases.

• Korean Journal of Breeding Science
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• v.42 no.5
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• pp.540-546
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• 2010

This study was conducted to understand the role of soybean pathogenesis-related 10 (GmPR10) gene in salt tolerance and to develop salt-tolerant rice using GmPR10 cDNA. GmPR10 transgene was expressed constitutively in the shoot and root of the $T_1$ transgenic rice plants. Interestingly, however, the levels of the transgene expression were increased temporally up to over four- to five-fold in the shoot and root by 125 mM NaCl treatment, peaking at six hours after the treatment and decreasing thereafter. Electrolyte leakage of leaf cells under 125 mM NaCl treatment was lower in all the transgenic lines than in the control variety, Dongjin-byeo. Ability of seedlings to recover from 125 mM NaCl treatment for two weeks was higher in the transgenic plants than in the control plants. These results demonstrated that GmPR10 had function to increase cell integrity and promote growth under the saline stress imposed by NaCl. The transgenic line GmPR10-3 which showed highest ability to recover from the saline stress could be used as a potential source for salt tolerance in rice breeding programs.