• KOREAN JOURNAL OF CROP SCIENCE
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• v.46 no.4
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• pp.309-316
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• 2001

Helianthus tuberosus has been known to inhibit the growth of weeds and other plants sharing its habitat. This study was conducted to identify the allelochemicals of Helianthus tuberosus which were extracted with water and solvents. Aqueous extracts of leaf, stem, root, tuber and tuber peel of Helianthus tuberosus except tuber did not show significant differences in phytotoxicity to alfalfa seedlings. It was considered that Helianthus tuberosus contained fewer or less potential water-soluble substances that were toxic to alfalfa. Methanol extract of leaves of Helianthus tuberosus was sequentially partitioned in increasing polarity with n-hexane, ethylacetate and n-butanol. Each extract had a yield of 148, 12, 15.7 and 9.5g, respectively. Inhibitory effects on germination of alfalfa seeds treated with four fractions were not significantly different. But the significant reductions on hypocotyl length were observed for all the solvent extracts. Among the four fractions, the ethylacetate fraction showed the most significant inhibition effect on bioassay with alfalfa. Further separation of the active ethylacetate fraction by open column chromatography led to the 25 subfractions. In bioassay of each sub-fraction with alfalfa seeds, sub-fraction No. 13 showed the most inhibitory effect on seedling growth. $^1$H NMR and gas chromatography-mass spectrometry analysis revealed that sub-fraction No. 13 was the mixture of straight-chain saturated fatty acids.

• Korean Journal of Plant Taxonomy
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• v.41 no.2
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• pp.171-174
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• 2011

A naturalized species, Silene antirrhina L is newly reported in Korea. S. antirrhina L. was found along the Geumho riverside in Daegu. S. antirrhina L. is similar to S. koreana Kom. and S. armeria L. in that it has dark glutinous areas. S. antirrhina L. can be distinguished from congeneric species by the stamens and styles of its sepal and seed surface which are finely papillate. The Korean name of S. antirrhina L. "Ganeun-Kkunkkunijangguchea" was newly formulated based on the overall characteristics of this thin and small plant and on the Korean name of S. koreana Kom. photos of the habitat and a description and key of characteristics are provided.

• International Journal of High-Rise Buildings
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• v.9 no.3
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• pp.221-233
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• 2020

Based on past experiences of natural disasters and fires in Japan, it is stipulated by law that fire-resistant buildings larger than a certain size should be unique in the world. Recent interest in global environmental issues has led to the active introduction of wooden buildings also in Japan, and it is expected that wooden buildings will become larger and higher in size. This paper introduces the background of the development of fire-resistant laminated timber with a "Self-Charring-Stop layer", the contents of this development including other related developments, and the application of these technologies. In addition, towards the realization of much larger and higher buildings in the future, the current problems and issues to be solved are set and the necessity of the future technological development is described. Finally, a conceptual model of wooden high-rise building is proposed, which will be able to be constructed in 2025 by the further technological development.

• Plant Resources
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• v.2 no.2
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• pp.127-132
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• 1999

This study was carried out to investigate the morphological characteristics of the plants and seeds of Ainsliaea acerifolia and to determine the optimum condition for producing sprouts from the seeds. Plant height, flower stalk length, and pod number were higher in natural habitat than in campus farm. Average 1.2 seeds per pod was set but only 0 to 2 seeds per plant was set in plants with the enveloped flower stalks, indicating that this is an outcrossing species. Most of seeds were 9-11mm long and 1.1-1.4mm wide. Fresh weight of seeds was ranged from 10mg to 17mg. Seeds germinated well at 15$^{\circ}C$ and 2$0^{\circ}C$. Mean germination period was 11.5 day at 15 to $25^{\circ}C$. Sprouts grown at 15$^{\circ}C$ was longest(5.4cm) and heaviest(738mg/10 sprouts). Chlorophyll content was 333mg per fresh weight 110g. Protein, Fe, vitamin Bl, vitamin B2, and vitamin C were respectively 23.7mg, 6.4mg, 1.82mg, 0.49mg, and 10..7mg.

• Mycobiology
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• v.44 no.1
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• pp.21-28
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• 2016

During a Korean mushroom diversity survey from 2011 to 2014, we found one new Xylaria species (X. ripicola sp. nov.) and one Xylaria species that had not been previously observed in Korea (X. tentaculata). To confirm the phylogenetic placement of the new species, we conducted a phylogenetic investigation based on internal transcribed spacer regions of ribosomal DNA sequences. Additionally, the new species, X. ripicola, was subsequently analyzed for RNA polymerase II subunit sequences. We also evaluated the macroscopic and microscopic features of this species. Herein, X. ripicola is described as a new species that was collected from a natural beach habitat and X. tentaculata is formally reported as newly found in Korea.

• Korean Journal of Plant Taxonomy
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• v.42 no.2
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• pp.167-170
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• 2012

During the course of the execution of the project entitled Distribution Research of Rare Plants, we found the habitats of two rare ferns with obscure and/or extremely restricted distribution ranges, as previously unreported habitats. A subantarctic fern reported on Hamgyeong-do and Gangwon-do, Dryopteris coreano-montana Nakai, was found on Mt. Ibam in Jangseong-gun, Jeollanam-do. A subtropical fern reported south of Jeju-do, Dryopteris decipiens (Hook.) Kuntze, was newly found on Mt. Cheongwan of Jangheung-gun in Jeollanam-do.

• Journal of Aquaculture
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• v.22 no.1
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• pp.83-91
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• 2009

The Korean doty barbel Hemibarbus mylodon (Cypriniformes; Cyprinidae) is a critically endangered freshwater fish species mainly because of its natural habitat degradation. Three full-length complementary DNA (cDNA) clones representing different muscle actin isoforms were isolated and characterized. The three muscle actin isoforms were 1,294-1,601 bp long with the identical open reading frames of 1,134 bp with the deduced amino acid residues of 377. They showed 83.9-87.2% identities in the coding nucleotide level and 96.8-98.1% identities in the amino acid level. Phylogenetic analysis with the coding nucleotide sequences revealed that three muscle actin isoforms of H. mylodon formed strongly supported monophyletic groups with one of cypriniform skeletal $\alpha$-actin (acta1), cypriniform aortic $\alpha$-actins (acta2), and uncharacterized Danio rerio muscle actin isoform/Salmo trutta slow muscle actin (a novel muscle actin type). Our phylogenetic tree further suggested that cypriniform acta2 only showed the orthologous relationship to tetrapod acta2. Other multiple actin isoforms from diverse teleostean taxa were however clustered to no tetrapod orthologs, i.e., acta1, cardiac $\alpha$-actins (aetc1), acta2, and enteric $\gamma$-actin (actg2). This result strongly suggested that teleostean muscle actins have experienced different and complicated evolutionary history in comparison to mammalian counterparts.

• Korean Journal of Plant Taxonomy
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• v.38 no.4
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• pp.565-571
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• 2008

In the course of execution for Inventories and Management of Plant Resources of Korea, We found new habitats of 4 plant species which distribution ranges are obscure and/or extremely restricted. A subtropical fern distributed in Jeju-do, Woodwardia japonica (L. f.) Sm., was found in Mt. Gambang-san of Hampyeong-gun, Jeollanam-do. A saprophytic orchid, Galeola septentrionalis Reichb., was found in Mt. Ggachi-bong of Boseong-gun, Jeollanam-do. Peristrophe japonica (Thunb.) Bremek., known in Jeollanam-do, was newly found in Mt. Mudeung-san of Gwangju-si. Viburnum furcatum Blume mainly distributed in Jeju-do and Ulleung-do was found in Mt. Jabyeong-san of Gangneung-si, Gangwon-do.

• Korean Journal of Plant Taxonomy
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• v.39 no.4
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• pp.292-295
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• 2009

Here, we report a previously unrecorded species, Sin-an-sae-u-nan-cho (Calanthe aristulifera Rchb. f.). It was discovered on Heuksan Island in Jeollanam-do. Its natural habitat was a subtropical forest. The species can easily be characterized by the simple trichomes on the back of its leaves and spur. This species is important because new horticultural races of Calanthe can be developed by cross-breeding with other species of Calanthe.

• Journal of Life Science
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• v.10 no.2
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• pp.169-176
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• 2000

At Koppl area, undamaged natural habitat of sundew, I have analysed interspecific affinities and community composition through mathematical method and important environmental factors. Interspecific affinities of the species with frequency of more than 5% in vegetation table were analysed through chi-square test and showed obvious group of Drosera rotundifolia, Vaccinium uliginosum, Calluna vulgaris, Eriophorum angustifolium and 21 species. The result of ordination anlysis using DECORANA of VESPAN II showed eigenvalue of 0.6047 for axis I, 0.2024 for axis II and 0.0763 for axis Ⅲ. And it divided into 4 groups of quadrat number 1-5 for Sphagnum squarrosum-community, 6-10 for Crepis paludosa-community. 11-25 for Carex panicea-community and 26-35 for Scorpidium scorpioides-community. By the classification using TWINSPAN, the 7 areas divided into 2 groups of 1-10 and 11-35 at first level of division with high eigenvalue of 0.588 and indicator was Sphagnum squarrosum. At second level of division it divided into 4 groups as the results of DECORANA with eigenvalues of 0.268 and 0.423 and indicators were Pinguicula vulgaris and Scorpidium scorpioides. Microclimatic environment of studied area was low in temperature and high in humidity and soil environment showed high in field moisture capacity, acid, high organic matter content, low NO3 and K2O content, compare to normal soil, and high ground water level.