• 한국작물학회:학술대회논문집
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• 한국작물학회 2003년도 춘계 학술대회지
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• pp.36-36
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• 2003

• Journal of Plant Biotechnology
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• 제6권4호
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• pp.213-219
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• 2004

Zygotic embryos were excised from immature and mature seeds of the Himalayan yew, Taxus wallichiana. The embryos germinated precociously when kept in darkness for 5 weeks and developed into full seedlings within 10-12 weeks. The highest rate of embryo germination ($81\%$) was obtained in modified Lloyd & McCown' s woody plant medium containing macro and micronutrients at half strength supplemented with $1\%$ activated charcoal, which supported both the best embryonic growth ($43\%$) and seedling development ($32\%$). However, the supplementation of basal media with kinetin, thidiazuron, 6-benzyl aminopurine or $GA_3$ had no effect on the germination of the embryos. The embryos derived from immature seeds germinated but the frequency of embryonic growth was better in mature seeds. Stratification of seeds effected precocious germination of embryos. Seeds kept at $4^{\circ}C$ for 1 week germinated earlier and at a higher frequency irrespective of the stage of seed maturity, while the germination rate declined with prolonged cold treatment for 1 month at that same temperature. Analysis of taxanes in germinating seedlings revealed that root tissues contained high levels of taxol, 10-deacetyl-baccatin ill and baccatin ill as compared to shoots. Thus embryo culture technique appears to overcome the lengthy dormancy requirement of T. wallichiana seeds.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2004년도 하계학술대회 논문집 Vol.5 No.1
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• pp.63-66
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• 2004

The extraordinary intrinsic properties of SiC have made this material a suitable choice to use in high temperature, high frequency, and high voltage applications. In additional to these, SiC could be employed as the based material for nonvolatile memory applications, mainly due to its extremely low thermal-generation rate at room temperature. In this paper, the reasons of using this material in this particular application is presented and the development of the application over the past fifteen years is reviewed.

• Journal of Microbiology and Biotechnology
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• 제27권8호
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• pp.1379-1385
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• 2017

The content of taxol in the bark of yews is very low, and this is not affordable from the environmental point of view. Thus, it is a necessity to look for alternative sources of taxol production to solve its supply. Currently, a large portion of the taxol in the market comes from chemical semi-synthesis, but the semi-synthetic precursors such as baccatin III and 10-deacetyl-baccatin III are extracted from needles and twigs of yew trees. Taxol-producing fungi as a renewable resource is a very promising way to increase the scale of taxol production. Our group has obtained a taxol-producing endophytic fungus, Aspergillus niger subsp. taxi HD86-9, to examine if A. niger can produce the taxanes. Six compounds from the fermentation broth of strain HD86-9 were isolated and identified by $^1H$ NMR, $^{13}C$ NMR, and ESI-MS. The results showed that the six compounds included four taxane diterpenoids (taxol, cephalomannine, baccatin III, and 10-deacetyl-baccatin III) and two non-taxane compounds (${\beta}-sitosterol$ and flavonoid isovitexin). The study verified that the taxanes can be produced by the A. niger, which is very important to taxol production via chemical semi-synthesis. Additionally, the finding is potentially very significant to solve the taxol semi-synthetic precursors extracted from needles and twigs of yew trees, and the precursor production can be easily increased through the culture condition optimization, genetic breeding, and metabolic engineering of the A. niger.

• 한국자원식물학회지
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• 제19권2호
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• pp.248-251
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• 2006

삼백초의 지상부 생육은 1년에서 2년차의 생육은 증가 폭이 컸으나, 2년에서 3년차의 생육은 감소하거나 부진하였다. 1년차에서는 소식일수록 생육이 양호하였으나, 3년생은 밀식할수록 차이가 없거나 감소하였다. 단위면적당 엽수와 경수는 재배년수가 경과하고 밀식할수록 많았다. 경엽(莖葉) 수량이 1년생은 밀식에서, 2년생은 $40{\times}10cm$에서, 3년생은 $40{\times}20cm$에서 가장 많았다. 근경중(根莖重)은 1년생에서 2년생은 중량의 증가폭이 켰으나, 2년생에서 3년생은 증가 폭이 둔화되었다. 재식거리간 근경중은 년차 간 고도의 유의성이 있었으며, 경엽중에 비해 매우 높았다.

• 공업화학
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• 제8권2호
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• pp.286-291
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• 1997

항암제로 탁월한 효능이 있는 taxol을 정상 액체 크로마토그래피를 이용하여 주목나무의 추출물에서 분리하였다. Taxol을 분리하기 위해 시료 주입량은 $5{\mu}l$에서 $100{\mu}l$로 변화시키고, 이동상 유속은 1ml/min로 고정하여 일정 용매법으로 실험을 하였다. 실험에 사용된 이동상은 헥산, 에탄올, 메탄올, 1-프로판올, 이소프로판올이었다. Taxol과 유사한 성질를 갖는 표준시료 cephalomannine, taxol, 10-deacetyltaxol의 혼합물에서 taxol을 분리하였다. Cephalomannine, taxol, 10-deacetyltaxol 혼합물의 분리 실험 결과로 taxol의 분리 최적 조건은 2성분계에서 헥산/에탄올의 부피 조성비가 96/4이며, 3성분계에서는 헥산/1-프로판올/메탄올의 부피 조성비가 96/2/2이었다. 분리시간은 2성분계에서 80분인데 비해 3성분계에서는 50분으로 적은 용매를 사용하여 분리할 수 있었다. 위에서 얻는 실험조건으로 실제 주목나무의 추출물 $1{\mu}g$에서 taxol를 분리할 수 있었다.

• 한국자원식물학회지
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• 제27권6호
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• pp.660-670
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• 2014

The Korean plum yew (Cephalotaxus koreana Nakai) is a shade-tolerant, coniferous shrub. The seeds have been used as a folk medicine in Korea, and an alkaloid extract (HTT) is known to have anticancer properties. We estimated the genetic diversity of 429 trees in 16 populations in South Korea using 194 polymorphic amplicons from seven combinations of AFLP primer-restriction enzymes. The average number of effective alleles and the percentage of polymorphic loci were 1.37 and 79.4%, respectively. Shannon's diversity index and the expected heterozygosity were 0.344 and 0.244, respectively. We divided 16 populations into four groups on the UPGMA dendrogram and the PCA biplot. The first two principal components explained 84% of the total genetic variation. Genetic differentiation between populations explained 14% of total genetic variation, and the remaining 86% came from difference between individuals within populations, as determined by an analysis of molecular variance (AMOVA). However, the genetic differentiation did not correlate with the geographic distance between populations from the Mantel test. The Bayesian statistics, which are comparable to Wright's $F_{ST}$ and Nei's $G_{ST}$, were ${\theta}^I=0.406$ and ${\theta}^{II}=0.172$, respectively. The population genetic diversity was slightly lower, and the strength of genetic differentiation was much weaker, than the average of those plants having similar life histories, as assessed using arbitrary marker systems. We discuss strategies for the genetic conservation of the plum yew in Korea.

• 한국응용곤충학회지
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• 제22권3호
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• pp.174-180
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• 1983

Five species, Hypothenemus californicus, Coccotrypes carpophagus, Othotomicus angulatus, Tomicus brevipilosus and Xyleborus seriatus were recognized firstly from Korea. Two species of them, H. californicus and C. carpophagus were preserved at Life Science Museum of Brigham Young university in U.S.A. X. seriatus intercepted at Kobe in Japan from imported yew log which had shipped at Nampo in North Korea was sent by Dr. F. G. Browne in England. Thirteen recorded species were also examined in this study.

• Asian review of World Histories
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• 제4권1호
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• pp.125-132
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• 2016

This paper, as a conlcusion to this special issue, presents the future work that is being carried out at NTU Singapore in collaboration with Microsoft Research and Microsoft Azure for Research. For our research team the real frontier research in world histories starts when we want to use computers to structure historical information, model historical narratives, simulate theoretical large scale hypotheses, and incent world historians to use virtual assistants and/or engage them in teamwork using social media and/or seduce them with immersive spaces to provide new learning and sharing environments, in which new things can emerge and happen: "You do not know which will be the next idea. Just repeating the same things is not enough" (Carlo Rubbia, 1984 Nobel Price in Physics, at Nanyang Technological University on January 19, 2016).

• 한국산림과학회지
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• 제15권1호
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• pp.39-41
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• 1972

일반적(一般的)으로 식별(識別)이 어려운 주목속(朱木屬) 5수종(樹種)의 심재추출물(心材抽出物)을 박층(薄層) chromatography로 전개후 디아조계 염료로 발색시켜 육안(肉眼), 형광(螢光) 및 자외선(紫外線)조사로 관찰한바 주목속(朱木屬)의 심재추출물의 박층(薄層)크로마토그람이 수종간에 현저한 차이가 있어 주목속(朱木屬)의 분류를 간단한 화학적방법(化學的方法)으로 가능케 하였다. 그 박층(薄層)크로마토그람의 색깔에 의한 분류기초는 다음과 같다.