• 제목/요약/키워드: Secondary resources

검색결과 802건 처리시간 0.028초

Development Changes of the Secondary Xylem Elements in Aristolochia manshuriensis Komarov (등칡의 2기목부요소의 발생학적 변이)

    • Korean Journal of Plant Resources
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    • 제11권3호
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    • pp.319-325
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    • 1998
  • The developmental changes occuring in the secondary xylem of Aristolochia manshuriensis Komarov have been studied in different ages of vine stems. A. manshuriensis possesses typical storeyed cambium comprising both vertically elongated fusiform initials and almost isodiametric ray cell initials. Stems of A. manshuriensis have wide rays that make the secondary xylem appear dissected as other vine types. The length of vessel member and fiber remained relatively constant throughout the secondary growth. However, vessel diameter increases with the increasing age of stem till the cell reaches their maximum limit and later more or less stabilize in diameter while number of vessel per $\textrm{mm}^2$ is vice versa. Width and relative proportion of ray to axial elements gradually increased with the increasing age of stem and later remained relatively constant.

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Isolation and Identification of Active Components from Natural Products (식의약소재 천연자원으로부터 유효성분 규명 연구)

  • Yeong-Geun Lee;Nam-In Baek;Se Chan Kang
    • Proceedings of the Plant Resources Society of Korea Conference
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    • 한국자원식물학회 2021년도 춘계학술대회
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    • pp.10-10
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    • 2021
  • Natural products have been used as drugs and cosmetics due to their bioactivity and their biochemical diversity. Natural products usually refer to secondary metabolites produced by various living organisms including marine animals, insects, microbes, amphibians, and plants. These secondary metabolites, which usually have molecular weights less than 2,000 amu, are unnecessary for survival, development, growth, and reproduction but play major roles in plant defense systems against other species. These secondary metabolites such as lignans, flavonoids, monoterpenes, and phenylethanoid glycosides showed various biological activities like anti-oxidant behavior, anti-cancer properties, neuroprotective properties, and so forth. Thus, isolation and elucidation of secondary metabolites from living organisms is of great significance to human life.

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A Study on Determining Archiving Priorities of Primary and Secondary Educational Resources (초·중등 교육자원 아카이브 구축을 위한 자원의 우선순위 선정에 관한 연구)

  • Kim, Seonghun;Do, Suelki;Oh, Sam G.
    • Journal of the Korean Society for information Management
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    • 제36권2호
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    • pp.153-174
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    • 2019
  • This study was conducted to find out basic facts on educational resources in Korea and see how educators have managed their tasks without educational resource archives. The research had the following steps: 1) finding out how the current state of primary and secondary education resources is managed and type of educational resources via Web search and literature review, 2) conducting a survey to determine archiving priorities according to the value of resources to the users, and 3) engaging in a discussion with experts on merits of establishing an educational resource archive system. Due to sporadic management and restricted use of educational resources produced in Korea, the primary and secondary education resources are not easily available to the public even though the public and private sectors produce significant amount of resources. The survey result on preferred educational resource types for archiving showed the following top three: 1) actual case studies conducted in the field, 2) curriculum related resources, and 3) various textbooks adopted. Considering the value of educational resources and the necessity of archiving agencies, the experts recommended to set up a national archiving system of educational resources. This study hopes to raise awareness of the need to set up educational resource archives as a start.

Draft Genome Sequence of Xylaria grammica EL000614, a Strain Producing Grammicin, a Potent Nematicidal Compound

  • Park, Sook-Young;Jeon, Jongbum;Kim, Jung A;Jeon, Mi Jin;Yu, Nan Hee;Kim, Seulbi;Park, Ae Ran;Kim, Jin-Cheol;Lee, Yerim;Kim, Youngmin;Choi, Eu Ddeum;Jeong, Min-Hye;Lee, Yong-Hwan;Kim, Soonok
    • Mycobiology
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    • 제49권3호
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    • pp.294-296
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    • 2021
  • An endolichenic fungus, Xylaria grammica strain EL000614, showed strong nematicidal effects against plant pathogenic nematode, Meloidogyne incognita by producing grammicin. We report genome assembly of X. grammica EL000614 comprised of 25 scaffolds with a total length of 54.73 Mb, N50 of 4.60 Mb, and 99.8% of BUSCO completeness. GC contents of this genome were 44.02%. Gene families associated with biosynthesis of secondary metabolites or regulatory proteins were identified out of 13,730 gene models predicted.