• Title/Summary/Keyword: new taxonomy

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Development of "Miscanthus" the Promising Bioenergy Crop (유망 바이오에너지작물 "억새" 개발)

  • Moon, Youn-Ho;Koo, Bon-Cheol;Choi, Yoyng-Hwan;Ahn, Seung-Hyun;Bark, Surn-Teh;Cha, Young-Lok;An, Gi-Hong;Kim, Jung-Kon;Suh, Sae-Jung
    • Korean Journal of Weed Science
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    • v.30 no.4
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    • pp.330-339
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    • 2010
  • In order to suggest correct direction of researches on Miscanthus spp. which are promising bioenergy crop, authors had reviewed and summarized various literature about botanical taxonomy, morphology and present condition of breeding, cultivation and utilization of miscanthus. Among the genus of Miscanthus which are known 17 species, the most important species are M. sinensis and M. sacchariflorus which origin are East Asia including Korea, and M. x giganteus which is inter-specific hybrid of tetraploid M. sacchariflorus and diploid M. sinensis. Miscanthus is superior to other energy crops in resistance to poor environments including cold, saline and damp soil, nitrogen utilization efficiency, budget of input energy and carbon which are required for producing biomass and output which are stored in biomass. The major species for production of energy and industrial products including construction material in Europe, USA and Canada is M. x giganteus which was introduced from Japan in 1930s. In present, many breeding programs are conducted to supplement demerits of present varieties and to develop "Miscanes" which is hybrid of miscanthus and sugar cane. In Korea, the researches on breeding and cultivation of miscanthus were initiated in 2007 by collecting germplasms, and developed "Goedae-Uksae 1" which is high biomass yield and "mass propagation method of miscanthus" which can improve propagation efficiency in 2009. In order to develop "Korean miscanthus industry" in future, the superior varieties available not only domestic but also foreign market should be developed by new breeding method including molecular markers. Researches on production process of cellulosic bio-ethanol including pre-treatment and saccharification of miscanthus biomass also should be strengthen.

Relationship between Science Education Researchers' Views on Science Educational Theories for Pre-service Science Teachers and the Examination for Appointing Secondary School Science Teachers (예비과학교사에게 필요한 과학교육학 이론에 대한 과학교육 연구자들의 의견과 중등과학교사임용시험의 연관성)

  • Lee, Bongwoo;Shim, Kew-Cheol;Shin, Myeong-Kyeong;Kim, Jonghee;Choi, Jaehyeok;Park, Eunmi;Yoon, Jihyun;Kwon, Yongju;Kim, Yong-Jin
    • Journal of The Korean Association For Science Education
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    • v.33 no.4
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    • pp.826-839
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    • 2013
  • The purpose of this study is to examine science education researchers' views on what and how much science educational theories would be needed for pre-service science teachers, and to investigate the relationship between their views and the Examination for Appointing Secondary School Science Teachers(EASST). For this study, the views of science education professors on science education theories have been analyzed in terms of their priorities for contributing to the improvement of science teacher competency and literacy. Their views have been compared with proportions of questions related to science education theories of the EASST in terms of what kinds of science education theories have been used for solving each item. As results of this study show, they have perceived that more essential things are needed for the improvement of science teacher competency and literacy including science inquiry process, methods of experimental equipments and tools, laboratory safety, misconception of students, discussion, writing, evaluation of scientific knowledges, and evaluation of scientific inquiry ability other than science philosophy, changes of science curricula, science curricula of foreign countries, Bruner's instructional theory, Karplus's Learning Cycle model, generative learning model, discovery learning model, and Klopfer's taxonomy of educational objectives. There is a higher proportion of questions related to science curriculum and Ausubel's learning theory in the EASST. They are hardly correlated with science education professors' selections of science educational theories for EASST questions. This study advocates the needs of exploring a new method of narrowing down the gap between science educators' opinions and questions of ESSAT in terms of science educaiton theories.

Paenibacillus kimchicus sp. nov., an antimicrobial bacterium isolated from Kimchi (김치로부터 분리된 항균 활성 세균 Paenibacillus kimchicus sp. nov.)

  • Park, A-rum;Oh, Ji-Sung;Roh, Dong-Hyun
    • Korean Journal of Microbiology
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    • v.52 no.3
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    • pp.319-326
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    • 2016
  • An antimicrobial bacterium to pathogenic microorganisms, strain $W5-1^T$ was isolated from Korean fermented-food Kimchi. The isolate was Gram-staining-variable, strictly aerobic, rod-shaped, endospore-forming, and motile with peritrichous flagella. It grew at $15-40^{\circ}C$, at pH 6.0-10.0, and in the presence of 0-4% NaCl. Strain $W5-1^T$ could hydrolyze esculin and xylan, and assimilate $\small{D}$-mannose, but not $\small{D}$-mannitol. Strain $W5-1^T$ showed antimicrobial activity against Listeria monocytogens, Pseudomonas aeruginosa, Staphylococcus aureus, and Salmonella typhi. The G+C content of the DNA of strains $W5-1^T$ was 52.6 mol%. The predominant respiratory quinone was menaquinone-7 (MK-7) and the major cellular fatty acids were $C_{16:0}$, antieiso-$C_{15:0}$, $C_{18:0}$, and $C_{12:0}$. The strain contained meso-diaminopimelic acid in cell-wall peptidoglycan. On the basis of 16S rRNA gene sequence and phylogenetic analysis, the strain W5-1 was shown to belong to the family Paenibacillaceae and was most closely related to Paenibacillus pinihumi $S23^T$ (98.4% similarity) and Paenibacillus tarimensis $SA-7-6^T$ (96.4%). The DNA-DNA relatedness between the isolate and Paenibacillus pinihumi $S23^T$ was 8.5%, indicating that strain $W5-1^T$ represented a species in the genus Paenibacillus. On the basis of the evidence from this polyphasic study, it is proposed that strain $W5-1^T$ is considered to represent a novel species of the genus Paenibacillus, for which the name Paenibacillus kimchicus sp. nov. is proposed. The type strain is $W5-1^T$ (=KACC $15046^T$ = $LMG 25970^T$).

Molecular phylogeny and the biogeographic origin of East Asian Isoëtes (Isoëtaceae) (동아시아 물부추속 식물의 분자계통 및 식물지리학적 기원에 대한 고찰)

  • CHOI, Hong-Keun;JUNG, Jongduk;NA, Hye-Ryun;KIM, Hojoon;KIM, Changkyun
    • Korean Journal of Plant Taxonomy
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    • v.48 no.4
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    • pp.249-259
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    • 2018
  • $Iso{\ddot{e}}tes$ L. ($Iso{\ddot{e}}taceae$) is a cosmopolitan genus of heterosporous lycopods containing ca. 200 species being found in lakes, streams, and wetlands of terrestrial habitats. Despite its ancient origin, worldwide distribution, and adaptation to diverse environment, species in $Iso{\ddot{e}}tes$ show remarkable morphological simplicity and convergence. Allopolyploidy appears to be a significant speciation process in the genus. These characteristics have made it difficult to assess the phylogenetic relationships and biogeographic history of $Iso{\ddot{e}}tes$ species. In recent years, these difficulties have somewhat been reduced by employing multiple molecular markers. Here, we reconstruct the phylogenetic relationships in East Asian $Iso{\ddot{e}}tes$ species. We also provide their divergence time and biogeographic origin using a fossil calibrated chronogram. East Asian $Iso{\ddot{e}}tes$ species are divided into two clades: I. asiatica and the remaining species. $Iso{\ddot{e}}tes$ asiatica from Hokkaido forms a clade with northeastern Russian and western North American $Iso{\ddot{e}}tes$ species. In clade I, western North America is the source area for the dispersal of $Iso{\ddot{e}}tes$ to Hokkaido and northeastern Russia via the Bering land bridge during the late Miocene. The remaining $Iso{\ddot{e}}tes$ species (I. sinensis, I. yunguiensis, I. hypsophila, I. orientalis, I. japonica, I. coreana, I. taiwanensis, I. jejuensis, I. hallasanensis) from East Asia form a sister group to Papua New Guinean and Australian species. The biogeographic reconstruction suggests an Australian origin for the East Asian species that arose through long-distance dispersal during the late Oligocene.