• Title/Summary/Keyword: morphological characteristics analysis

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A Newly Recorded Sea Cucumber of the Genus Psolus (Holothuroidea: Dendrochirotida: Psolidae) from the East Sea of Korea

  • Lee, Taekjun;Shin, Sook
    • Animal Systematics, Evolution and Diversity
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    • v.33 no.3
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    • pp.195-199
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    • 2017
  • A sea cucumber was collected from Gonghyeonjin in the East Sea of Korea at a depth of 50 m on 22 June 2011 and was identified as Psolus phantapus (Strussenfelt, 1765). This species belongs to the family Psolidae of the order Dendrochirotida based on morphological characteristics and mitochondrial cytochrome c oxidase subunit I sequence analysis. Psolus phantapus, which widely distributes in the Arctic and North Atlantic Oceans, is newly recorded in the Korean fauna. Two Psolus species including the previously reported P. squamatus are recorded in the East Sea of Korea.

Morphological Characteristics of Granular Sludge in dPAO SBR (dPAO SBR 입상슬러지의 형태학적 특성)

  • Yoo, Tae Uk;Lee, Hansaem;Yun, Geumhee;Yun, Zuwhan
    • Journal of Korean Society on Water Environment
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    • v.29 no.4
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    • pp.497-503
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    • 2013
  • The morphological characteristics of granules, which were generated in lab-scale sequencing batch reactor (SBR) for simultaneous nitrogen and phosphorus removal with denitrifying phosphorus accumulating organism (dPAO) were identified. Granular sludge was fully developed in the anaerobic-anoxic (An-Ax) SBR after 180 days of SBR operation. The average diameter of granular sludge was 2.2 mm and rod-type organisms dominated in the granules. In addition, about 1.0 mm of white precipitate was observed in the core of the granule, and the material was confirmed that it is very similar to hydroxyapatite $(HAP;\;Ca_5(PO_4)_3(OH))$ by X-ray diffraction) analysis.

Effect of Ar- Plasma Treatment on Mechanical Properties of Acrylic Fiber (아크릴섬유의 기계적 물성에 대한 알곤플라즈마 처리의 영향)

  • Seo Eon Deock
    • Textile Coloration and Finishing
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    • v.16 no.6
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    • pp.30-34
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    • 2004
  • Polyacrylontrile fiber was modified with argon low temperature plasma by RF glow discharge at 240 mTorr, 40 W to investigate the surface morphological changes and mechanical characteristics such as elongation, tenacity, and modulus. Analysis of the SEM images revealed that the plasma treatment resulted in significant ablation on the surfaces rendering a severe crack formation. The morphological changes were evident with short treatment time of argon plasma although longer treatment time damaged the surface more severely. The mechanical characteristics such as tenacity and elongation were deteriorated due to the plasma treatment. The tenacity of the fiber treated with argon-plasma for 5 min showed a decreased value up to 21.9 % when compared to the untreated fiber. While the corresponding initial modulus(0 - 1 %) increased markedly up to 44.3 %.

Anatomical and Morphological Features of Seeds in Portulaca

  • Kim, InSun
    • Applied Microscopy
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    • v.42 no.4
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    • pp.194-199
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    • 2012
  • The anatomy and morphology of seeds from 10 Hawaiian Portulaca taxa were examined to explore patterns of variation among the taxa, and to evaluate their phylogenetic relationships. Features of seeds were assessed employing microtechnique procedures, statistical analysis, and scanning electron microscopy (SEM). Anatomically, the orientation of embryo was consistent across taxa, and all seeds examined had central nutritive tissue and integuments comprising the peripheral embryo. Seeds were generally small, circular to ovoid in shape, and either smooth or rough-surfaced, with tubercules. Variation in seed size was noted, although minimal within small seeded group. The size of seeds ranged from 0.50~1.26 mm in length, and 0.55~1.34 mm in width, with similar weights. Seeds were distinguished by the sculpture and arrangement of the testa epidermis and the way in which their stellulate-tessellate cells uniquely fit together. Using a multiple range test (ANOVA), two groups were established by seed characteristics. The SEM also demonstrated morphological differences in testa sculpturing. The results obtained confirm the usefulness of seed characteristics in the identification of the species examined, and furthermore, allow for the separation of the Hawaiian Portulaca into two groups.

A Comparative Study on the Morphological Characteristics of PAO and dPAO Granule (PAO와 dPAO 입상슬러지의 형태학적 특성에 대한 비교 고찰)

  • Yun, Geumhee;Yun, Zuwhan
    • Journal of Korean Society on Water Environment
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    • v.33 no.3
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    • pp.302-310
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    • 2017
  • The morphological characteristics of granules developing in anaerobic-anoxic (An-Ax) and anaerobic-aerobic (An-Ox) sequencing batch reactors (SBRs) were examined. The granules developed in the both SBRs after 200 days of laboratory operation. The average diameters of the granules were $2.2{\pm}1.7mm$ in the An-Ax SBR and $0.4{\pm}0.3mm$ in the An-Ox SBR. To determine the possible factors affecting morphology of granules a comparative analysis of various operating conditions from reference data indicated that the availability and type of electron acceptors is a key factor determining the granulation process and granular morphology.

A New Report on Oidiodendron flavum Isolated from Field Soil in Korea

  • Adhikari, Mahesh;Kim, Sangwoo;Yadav, Dil Raj;Babu, Anam Giridhar;Kim, Changmu;Lee, Hyang Burm;Lee, Youn Su
    • The Korean Journal of Mycology
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    • v.42 no.3
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    • pp.235-238
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    • 2014
  • Oidiodendron flavum KNU13-6 was isolated for the first time from field soil in Korea and identified based on the internal transcribed spacer region (ITS) of rDNA and morphological characteristics. Based on phylogenetic analysis of ITS and morphological characteristics, the species has not been previously reported in Korea.

Four Unreported Endophytic Fungi Isolated from Roots of Quercus spp. in Korea

  • Choi, Jae-Wook;Gwon, Ju-Hui;Park, Hyeok;Lee, Jong-Chul;Eom, Ahn-Heum
    • The Korean Journal of Mycology
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    • v.49 no.3
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    • pp.325-335
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    • 2021
  • We isolated endophytic fungi from the roots of Quercus spp. in Korea. The isolates were identified based on morphological and molecular characteristics from the nucleotide sequences of the internal transcribed spacer and large subunit of rDNA regions. We confirmed that the four species we isolated - Oidiodendron citrinum, Acremonium crotocinigenum, Mammaria echinobotryoides, and Pleotrichocladium opacum - have not been recorded previously in Korea. Herein, we present their morphological characteristics and the result of phylogenetic analysis.

Report on Tuber huidongense, a Truffle Species Previously Unrecorded in Korea

  • Park, Hyeok;Gwon, Ju-Hui;Lee, Jong-Chul;Kim, Hyun Suk;Oh, Deuk Sil;Eom, Ahn-Heum
    • The Korean Journal of Mycology
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    • v.48 no.4
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    • pp.505-510
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    • 2020
  • The fruiting bodies and roots of a Tuber species were collected from the rhizosphere of Quercus dentata in Pohang, Korea. The morphological characteristics of the ascoma and ectomycorrhizal roots were studied, and phylogenetic analyses were performed using the sequences of the internal transcribed spacer, large subunit rDNA, and β-tubulin DNA. Based on the features of the fruiting bodies, the species was identified to be Tuber huidongense, which has not been reported earlier in Korea. The morphological characteristics and phylogenetic analysis of T. huidongense are described in the present study.

Acrodontium burrowsianum and Pestalotiopsis humicola: Two Previously Unrecorded Fungal Species Isolated from Conifer Leaves in Korea

  • Jae-Wook Choi;Jung-Min Lee;Seok-Yong Park;Ahn-Heum Eom
    • The Korean Journal of Mycology
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    • v.50 no.4
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    • pp.311-318
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    • 2022
  • Endophytic fungal strains were isolated from the leaves of two conifer species (Juniperus rigida and Pinus densiflora) in Korea and identified on the basis of their morphological and molecular characteristics. Internal transcribed spacer and large subunit regions of rDNA were used for the phylogenetic analysis, and the translation elongation factor 1-alpha (TEF) and RNA polymerase II second largest subunit (RPB2) genes were analyzed depending on the species. Two fungal species that were previously unrecorded in Korea were identified: Acrodontium burrowsianum and Pestalotiopsis humicola. Their morphological and phylogenetic characteristics are described herein.

Seven Unrecorded Species of Ascomycota Isolated from the Rhizosphere Soils of Apple and Pear Trees in Korea

  • Hyeongjin Noh;Hyun Uk Cho;Jun Woo Cho;Seong Jae Ahn;Seong Hwan Kim
    • The Korean Journal of Mycology
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    • v.51 no.4
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    • pp.471-490
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    • 2023
  • Soil is a rich source of saprobic and pathogenic fungi in crop cultivation areas. Compared with that of the fruit trees, scarce information is available regarding the fungi present in orchard soils in Korea. We sampled rhizosphere soils of apple and pear trees from several orchards in Cheongju, Anseong, and Cheonan, Korea. During the processing of soil fungi, seven unrecorded species of the phylum Ascomycota were isolated. These included Acrocalymma walkeri, Clonostachys krabiensis, Coniella vitis, Cosmospora diminuta, Lasiobolidium spirale, Penicillium vallebormidaense, and Pseudothielavia arxii. All the species were identified and described based on morphological characteristics and molecular analysis of the ITS1-5.8S-ITS2 region and the large subunit of nuclear ribosomal RNA gene and partial β-tubulin gene (BenA) sequences. Descriptions and illustrations of the morphological characteristics are provided.