• Korean Journal of Plant Tissue Culture
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• v.22 no.3
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• pp.143-148
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• 1995

The competence of callus formation and plant regeneration from root derived callus was higher in japonica cultivars than those of Tongil-type cultivars of rice. A japonica type cultivars Yeongdeogbyeo, showed the highest capacity (13%) for plant regeneration from root calli of 6 cultivars tested. The callus induced from seed and root tissues maintained higher capacity for plant regeneration during 7 passages of subculture on N$_{6}$ solid media at 2-week intervals. The maximum frequency (2 x 10$^{5}$ mL) of round cells and their cell colonies showed about 24 days after suspension culture of root-derived callus in N$_{6}$ medium with lmg/L 2,4-D, 300mg/L casein hydrolysate, 10mM L-proline, 20g/L sucrose and 30g/L sorbitol. The frequency of somatic embryo formation in suspension cultures of root-derived callus increased with prolonged advance of subculture time from 30 to 90 days, but their regenerative capacities decreased.

• Journal of Life Science
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• v.14 no.4
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• pp.702-707
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• 2004

In native-polyacrylamide gel electrophoresis of Pangasius polyuranodon, the lactate dehydrogenase (EC 1.1.1.27, LDH) $A_4$, $A_3$B, $A_2$$B_2$,$AB_3$ and $B_4$ isozymes were expressed in various tissues. The LDH $A_4$ and liver-specific $C_4$ isozymes were expressed in the tissues of Hypostomus Plecostomus. The bands of LDH in skeletal muscle, heart and eye tissues were not detected while one band was detected in kidney and liver, and four bands were detected in brain. The detected one band in liver was identified as alcohol dehydrogenase and an anodal band of skeletal muscle was identified as nothing dehydrogenase. The LDH in skeletal muscle, heart and eye might function as pyruvate reductase. The degree of inhibitions of LDH in skeletal muscle and heart of P. polyuranodon by 10 mM pyruvate were measured 57.6% and 73.8%, respectively. However, those of LDH in tissues of H. plecostomus were measured 52.7-61.8% so tissue specificity did not appear. Therefore, H. ple-costomus might be more acclimated to hypoxic environment by anaerobic metabolism of LDH iso-zymes than P. polyuranodon.

• Horticultural Science & Technology
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• v.30 no.4
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• pp.371-377
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• 2012

This study was conducted to investigate the physiological and structural damages to cadmium (Cd) in Acorus calamus var. angustatus as a native aquatic species in Korea. In addition to the physiological responses such as plant growth, photosynthesis, and root activity, the structural damages in leaf and root tissues were observed through light and scanning electronic microscopy. The five-leaf plants were treated with different Cd concentrations 0, 10, 25, and 50 ${\mu}M$ for 15 days. The plant damages to Cd were significant at 10-25 ${\mu}M$ Cd physiologically and at 25-50 ${\mu}M$ Cd structurally. The physiological damages in the shoot part (photosynthesis) started at 10 ${\mu}M$ Cd whereas those in root part (root activity) were serious above 25 ${\mu}M$ Cd. On the other hand, the structural damages began at 25 ${\mu}M$ Cd in the leaf and root tissues similarly, but the plant tissue destruction was more serious in the roots than in leaves. Based on the plant physiological and structural damages, 10 ${\mu}M$ was assumed to be the limited concentration for sustainable growth and landscaping ability in Acorus calamus var. angustatus to Cd.

• Proceedings of the Korea Information Processing Society Conference
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• 2008.05a
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• pp.367-370
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• 2008

소프트웨어 제품의 신뢰성과 안정성 확보를 위한 품질 보증이 중요해짐에 따라 독립된 테스트 조직이 증가되고 이러한 테스트 조직은 효과적 효율적으로 테스트 활동을 수행하기 위해 테스트 프로세스 개선을 필요로 한다. 그러나, 프로세스는 제품의 도메인 특성으로부터 많은 영향을 받아 특화되므로 실시간(Time to Market) 서비스가 강조되는 웹 서비스 시스템에서의 테스트 프로세스에 대한 연구가 부족하므로 테스트 조직 향상을 위한 방향 모델과 이를 이행할 수 있는 접근 방법을 필요로 한다. 본 연구에서는 웹 서비스 제품의 품질을 보증하기 위해 검증 작업을 수행하고 있는 테스트 조직이 향상되기 위한 방안으로 TMM을 적용하였고, 성숙된 프로세스 구축을 위한 방법으로 GQM을 이용하여 메트릭을 도출한 사례를 제시하였다. 이런 연구결과는 도메인 특성에 맞게 도출된 매트릭을 통해 제품과 테스터의 능력을 평가하고 결과 값을 프로세스 개선에 반영하여 정량적인 데이터 기반으로 관리되는 테스트 조직으로 발전할 수 있을 것이다.

• Journal of Life Science
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• v.24 no.7
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• pp.743-749
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• 2014

The aim of this study was to identify the effect of fermented Angelica gigas Nakai (A. gigas) on lipid metabolism in orotic acid-induced fatty liver model rats. Sprague-Dawley male rats were randomly divided into four dietary groups (n=6 per group): a normal (N) group fed a standard diet only, OA control, OA acid plus 5% (w/w) A. gigas (OAG), and OA plus 5% (w/w) fermented A. gigas (OFAG). OA treatment induced enlargement of the liver and accumulation of hepatic triglycerides. The consum ption of fermented A. gigas reduced triglyceride concentrations in the liver and increased the serum lipid concentrations to normal levels. Furthermore, OA treatment significantly decreased serum triglyc eride concentrations without diminishing mRNA expression of microsomal triglyceride transfer protei n (MTP) and protein disulfide isomerase (PDI). Hepatic MTP mRNA expression increased 1.08-fold in response to OA treatment, despite triglyceride accumulation in the liver relative to that of the normal group. OFAG administration was slightly lower as compared to the OA treatment. This result suggests that MTP mRNA expression is not always correlated with hepatic triglyceride accumulation in the OA-induced fatty liver model. However, PDI mRNA expression was significantly increased in the OAG and OFAG groups (1.62-fold and 1.63-fold, respectively) compared with the normal group. The hepatocytes in the OA group contained numerous large fat droplets. These were slightly reduced in the OFAG group.

• Journal of Life Science
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• v.18 no.2
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• pp.264-272
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• 2008

The lactate dehydrogenase (EC 1.1.1.27, LDH) isozymes in tissues from Acanthogobius hasta were characterized by biochemical, immunochemical and kinetic methods. The activities of LDH in skeletal muscle and eye tissues were 65.30 and 53.25 units, but LDH activities in heart and liver tissues were very low. LDH/CS (EC 4.1.3.7, citrate synthase) in skeletal muscle was the highest as 22.29. Specific activities of LDH in brain, eye and skeletal muscle were 56.45, 38.04 and 11.0 units/mg, respectively. The LDH isozymes in tissues were separated by polyacrylamide gel electrophoresis after immunoprecipitation with antiserum against $A_4,\;B_4$ eye-specific $C_4$ and liver-specific $C_4$. LDH $AC_4$ isozymes were detected predominantly in skeletal muscle, brain and eye tissues, and $B_4$ isozyme was detected in heart. Anodal eye-specific $C_4$ and cathodal liver-specific $C_4$ were coexpressed in A. hasta. The eye-specific $C_4$ isozyme showed higher activity in eye tissue, but liver-specific $C_4$ isozyme showed lower activity in liver. As a result, one part of molecular structures in $A_4\;and\;C_4,\;A_4\;and\;B_4$, and eye-specific $C_4$ and liver-specific $C_4$ were similar, but in $B_4\;and\;C_4$ were different with each other. Therefore the subunit A may be conservative in evolution, and the evolution of subunit B seems to be faster than that of subunit A. The LDH $A_4$ isozyme of skeletal muscle was purified in the fraction from elution with NAD+ containing buffer of affinity chromatography and eye-specific $C_4$ isozyme was eluted right after $A_4$, so the structure of eye-specific $C_4$ isozyme is similar to $A_4$. And LDH activity remained 35.22-43.47% as a result of the inhibition by pyruvate, the Michaelis-Menten constant values for pyruvate was 0.080-0.098 mM, and Vmax were 153.85 units, 35.09 units in skeletal muscle and eye, respectively. Also the $B_4$ isozyme was the thermo-stablest and $C_4$ was stabler than $A_4$ isozyme. The optimum pH of LDH was 6.5. The results mentioned above indicate that isozymes in tissues showed the properties between LDH $A_4\;and\;B_4$ isozyme as A. hasta was adapted to hypoxic conditions. Also LDH seems to function more effectively under anaerobic condition because LDH in skeletal muscle and eye tissues have high affinity for pyruvate.

• Proceedings of the Korea Information Processing Society Conference
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• 2016.04a
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• pp.539-541
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• 2016

소프트웨어 중심 사회에서 소프트웨어의 개발과 운영에 대한 효율성을 극대화하기 위해 운영 조직과 개발 조직을 통합한 개발운영조직 통합관리 방법론을 적용하고 있다. 클라우드 환경을 이용하여 서비스를 중단 없이 운영하는 지속적 배포 시스템에서 개발운영조직 통합관리를 적용 하였을 때, 운영 조직의 요구사항과 사용자의 요구사항 등으로 인한 작은 규모 크기의 배포가 빈번하게 발생하게 된다. 이와 같은 시스템은 다양한 보안 위협으로부터 안전하지 않다. 따라서, 본 연구에서는 클라우드 환경에서 지속적 배포시스템의 개발운영조직 통합관리에서 발생할 수 있는 문제점과 보안에 대한 개선사항을 제시하고자 한다.

• Journal of Plant Biology
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• v.35 no.4
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• pp.409-414
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• 1992

Effect of quercetin, a kind of natural plant flavonoids, on auxin-induced ethylene production in barley coleoptiles was studied. Auxin-induced ethylene production was apparently stimulated by quercetin. This stimulatory effect of quercetin appeared after 4 h of incubation period. Ethylene production was stimulated 200% over the control after 8 h of incubation by $3{\times}10^{-5}\;M$ quercetin. The quercetin effect was most prominent at $10^{-4}\;M$ of IAA. Ethylene production induced by the synthetic auxin, 2,4-D and NAA, was not significantly affected by quercetin. Also ACC-based ethylene production was unaffected by the flavonoid. In an effort to elucidate mechanisms of quercetin action on auxin-induced ethylene production, the effect of quercetin on 1M metabolism was studied. Data obtained from these experiments indicate that quercetin treatment resulted in about 90% inhibition of IAA oxidase activity. IAA ($3{\times}10^{-5}\;M$) conjugation was found to be not affected by quercetin. This results suggest that the stimulatory effect of quercetin on auxin-induced ethylene production may be due to the fact that quercetin inhibits 1M oxidase activity, thus increasing the free IAA level.

• Journal of the Korean Magnetics Society
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• v.12 no.1
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• pp.34-40
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• 2002

In order to improve the microstructure of the strip cast Nd-Fe-B alloys that are frequently used for production of high energy sintered magnets, influence of various strip casting conditions on the microstructure and phase formation and distribution were investigated. Nd-Fe-B strips consisting of microstructures suitable for preparation of high energy sintered magnets could be obtained when the wheel speed was below 5 m/s. The compositional limit that can avoid the crystallization of free iron in the as-cast state was estimated to be Nd$\_$14/Fe$\_$79/B$\_$7/. Regardless of the compositional variation, <001> preferred orientation of Nd$_2$Fe$\_$14/B normal to the strip surface was always occurred below 5 m/s, which would eventually enhance the grain alignment during pressing the powder under a magnetic field. While the coercivity of the strip cast alloys increased with the increase of the wheel speed, mainly due to the refinement of Nd$_2$Fe$\_$14/B grains, it decreased with the reduction of Nd content in the alloy composition as the formation of free iron increased.

• Korean Journal of Ichthyology
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• v.23 no.1
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• pp.21-29
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• 2011

Expression analysis of development-related genes was conducted using differential screening of 6-month-old [18M(-), 6M-18M] specific and 18-month-old [6M(-), 18M-6M] specific subtracted cDNA libraries constructed by subtractive hybridization using skeletal muscle of 6- and 18-month-old dark-banded rockfish Sebastes inermis. A total 202 cDNA clones displaying different expression levels in each stage were obtained; among them, 32 clones showing up-regulation were finally selected for further expression analysis. We sequenced the clones and analyzed individual sequences. Genes expressed specifically in 6-month-old skeletal muscle were identified as myosin, adenylate kinase, calsequestrin, dystrobrevin beta, and diphosphate kinase-Z1. Genes showing strong expression in 18-month-old rockfish were identified as desmin, TGFBR2 (transforming growth factor-beta receptor), muscle-type creatine kinase, and cathepsin D. Expression of these genes was checked further in 6-18-30-42 month-old dark-banded rock fish. Rapid reduction of expression was observed in dystrobrevin beta and diphosphate kinase. However, expression of creatine kinase (muscle type) and cathepsin D increased as dark-banded rockfish grew, and remained even after 18 months. The results reported here demonstrate that genes related to muscles contract are expressed at an early stage of development, and genes controlling energy in muscles are predominantly expressed at a late developmental stage.