• Title/Summary/Keyword: morphological narrow

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Taxonomic Study of Peltigera (Peltigeraceae, Ascomycota) in Korea

  • Wei, Xin Li;Wang, Xin Yu;Koh, Young-Jin;Hur, Jae-Seoun
    • Mycobiology
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    • v.37 no.3
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    • pp.189-196
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    • 2009
  • A taxonomic study of Peltigera in South Korea was performed. The phylogenetic analysis based on nr DNA internal transcribed spacer sequences suggests that Peltigera is a well-supported monophyletic group. Important characteristics are the phycobiont type of thallus and the vein type at the lower cortex (wide and flat, or narrow and ridged). The vertical or horizontal arrangement of the apothecia is also important in distinguishing species in this genus. Eleven species of Peltigera were revealed and confirmed, which included one new record, P. elisabethae. A description of each species is presented with morphological, anatomic, and chemical characteristics, and comparisons between similar species are made. A key to the species is also presented.

STAR FORMATION ACTIVITY OF GALAXIES IN A NEARBY COMPACT GROUP: THE NGC 4095 GROUP

  • POOJON, PANOMPORN;SAWANGWIT, UTANE;KRIWATTANAWONG, WICHEAN
    • Publications of The Korean Astronomical Society
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    • v.30 no.2
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    • pp.507-509
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    • 2015
  • This work aims to study the evolution of galaxies, located in the dense environment of the NGC 4095 compact group, which have recession velocities 6,000 < v ($km\;s^{-1}$) < 8,000. Imaging observations for BV $R_c$ broad-band, and [$S\small{II}$] and red-continuum narrow-band were carried out with the 2.4 m Thai National Telescope (TNT) at Doi Inthanon, Chiang Mai, Thailand. The sample contains 13 galaxies, consisting of 8 spirals, 4 ellipticals and 1 irregular morphological type. Late type galaxies tend to be bluer than early type galaxies. The results show that most of the late type galaxies have ongoing star formation activity, which could be triggered by galaxy-galaxy or tidal interactions, and that young massive stars in these galaxies cause their colors to be bluer than the early type galaxies.

Bremia itoana (Oomycota, Peronosporales), a Specialized Downy Mildew Pathogen on an East Asian Plant, Crepidiastrum sonchifolium (Asteraceae)

  • Choi, Young-Joon;Park, Ji Hoon;Lee, Jeongran;Shin, Hyeon-Dong
    • Mycobiology
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    • v.46 no.4
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    • pp.416-420
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    • 2018
  • Crepidiastrum sonchifolium, a flowering plant in the daisy family (Asteraceae), is native to East Asia. In Korea, this plant is a locally cultivated vegetable, and its market size is gradually growing. Since the plants with downy mildew infection were initially found at a private farm of Chuncheon city, the occurrences have continued in commercial farms of other regions, highlighting that this disease is spreading throughout Korea. The pathogen was attributed to a member of the genus Bremia that contains many specialized species, each of which displays a narrow host spectrum on Asteraceae. Based on morphological and molecular phylogenetic analyses, along with the high host specificity recently proven for Bremia species, the identity of the causal agent was confirmed as a so far undescribed species of Bremia. Here, we introduce Bremia itoana sp. nov., specific to C. sonchifolium.

A Study of the Speaking-Centered Chinese Pronunciation Teaching Method for Basic Chinese Learners. (초급 중국어 학습자를 위한 발음교육 개선방안 - 말하기 중심 발음 교수법 -)

  • Lim, Seung Kyu
    • Cross-Cultural Studies
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    • v.35
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    • pp.339-368
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    • 2014
  • In Teaching Chinese as a Foreign Language, phoneme-based pronunciation teaching such as tone, consonants, vowels is the most common teaching methods. Based on main character of Chinese grammar: 'lack of morphological change' in a narrow sense, was proposed by Lv Shuxiang and Zhu Dexi, I designed 'Communicative oriented Chinese pronunciation teaching method'. This teaching method is composed of seven elements: one kind is the 'structural elements': phoneme, word, phrase, sentence; another kind is the 'functional elements': listening, speaking and translation. This pronunciation teaching method has four kinds of practice methods: 1) phoneme learning method; 2) word based pronunciation practice; 3) phrase based pronunciation practice; 4) sentence based pronunciation practice. When the teachers use these practice methods, they can use the dialogue and Korean-Chinese translation. In particular, when the teachers use 'phoneme learning method', they must use Korean and Chinese phonetic comparison results. When the teachers try to correct learner's errors, they must first consider the speech communication.

The First Record of the Marphysa victori (Polychaeta, Eunicida, Eunicidae) from Korea, with DNA Barcode Data

  • Kim, Hana;Kim, Keun-Yong;Phoo, War War;Kim, Chang-Hoon
    • Animal Systematics, Evolution and Diversity
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    • v.37 no.1
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    • pp.1-8
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    • 2021
  • A eunicid polychaete, Marphysa victori Lavesque, Daffe, Bonifácio & Hutchings, 2017 is described for the first time from the intertidal zones of the Korean coasts. It is characterized by having three types of pectinate chaetae (INS, isodont-narrow-slender; AWS, anodont-wide-slender; and AWT, anodont-wide-thick), appearance of pectinate chaetae from chaetiger 2, the chaetae consisted of pectinate and compound spinigers, and pygidium with one pair of pygidial cirri. In genetic analysis based on cytochrome c oxidase subunit I (COI), intra-specific genetic distance between the specimens of M. victori from its type locality, France and Korea are in the range of 0.000-0.013. This paper includes the morphological description and photographs of M. victori new to Korean fauna, with partial sequences of the mitochondrial COI as DNA barcode data on this species.

A New Free-Living Marine Nematode, Chaetonema longicorpus sp. nov. (Enoplida: Anoplostomatidae) from a Subtidal Zone of the East Sea, Korea

  • Lee, Hyo Jin;Lee, Heegab;Rho, Hyun Soo
    • Animal Systematics, Evolution and Diversity
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    • v.38 no.4
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    • pp.205-213
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    • 2022
  • A new free-living marine nematode, Chaetonema longicorpus sp. nov., was discovered in a subtidal benthic habitat around the Uljin nuclear power plant in the East Sea. Chaetonema longicorpus sp. nov. differs from other Chaetonema species in its very long body length, relatively long cephalic setae, long and narrow buccal cavity, bottle-shaped amphideal fovea, short spicules, only one pre-cloacal seta instead of a pre-cloacal supplement, and conspicuous ventral swelling at the middle of the tail. Herein, we provide a taxonomic description and illustrations of this new species using differential interference contrast microscopy. Furthermore, an illustrated pictorial key to all valid species, including the new species and comparative tables on the biogeographical and morphological characteristics of the genus Chaetonema, are provided.

Saxifraga cortusifolia (Saxifragaceae): A new record for the Korean flora from Jejudo Island

  • Jae-Seo SHIN;Yong-In KIM;Eui-Kwon JUNG;Ji Hoon KIM;Bo-Yun KIM;Young-Dong KIM
    • Korean Journal of Plant Taxonomy
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    • v.52 no.4
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    • pp.251-254
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    • 2022
  • Saxifraga cortusifolia Siebold & Zucc. (Saxifragaceae, sect. Irregulares, ser. Rufescentes), a species considered endemic along mountain streams throughout Honshu, Shikoku, and Kyushu in Japan, was discovered as a wild population in the Cheona Valley in Haean-dong, Jeju-si on Jeju-do Island of Korea. The population consisted of three subpopulations occupying narrow areas 10 × 10 m2, 5 × 5 m2, and 10 × 5 m2 in size. The number of individuals in the three subpopulations was confirmed to exceed 100. Most of the individuals were on or below rocks at the edge of the valley. A morphological description, detailed photos, and a key to related taxa in Korea are presented.

Chromosome number of Carex brevispicula (Cyperaceae), a sedge endemic to Korea

  • Kyong-Sook CHUNG;Gi Heum NAM;Gyu Young CHUNG
    • Korean Journal of Plant Taxonomy
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    • v.53 no.2
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    • pp.166-169
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    • 2023
  • Carex brevispicula (Cyperaceae) is endemic to Korea and is characterized by constricted achenes, short lateral spikes, and awned staminate and pistillate scales. The species classified in sect. Mitratae occurs throughout South Korea, perennating on mountains and/or rocky slopes under half shadow conditions. Meiotic chromosomes of the species were examined in this study, in which 33 meiotic cells from seven populations were found to be less than 2 ㎛ long with non-constricted chromosomes (n = 34II). The stable chromosome number may be related to the narrow geographical distribution and/or distinct achene morphology. Further investigations of the distribution, morphological character variation, and chromosome characteristics should be conducted with closely related taxa to understand the derivation of the species and its endemism in Korea.

Ultrastructure of the fertilized egg envelopes in Ancistrus cirrhosus, Loricariidae, Teleostei

  • Dong Heui Kim
    • Applied Microscopy
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    • v.50
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    • pp.13.1-13.7
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    • 2020
  • We examined the morphology of fertilized egg and ultrastructures of fertilized egg envelopes of Ancistrus cirrhosus belong to Loricariidae using light and electron microscopes. The fertilized eggs formed a mass on the spawning place and were yellowish, spherical, non-transparent, demersal, adhesive, and a narrow perivitelline space. But, the adhesiveness of fertilized eggs was disappeared after spawning excluding contact parts. The micropyle with funnel shape was surrounded by 15-19 furrow lines of egg envelope in a spoke-like pattern. The outer surface of egg envelope has smooth side and inner surface of egg envelope was rough with grooves. Also, the total thickness of the fertilized egg envelope was about 32.58 ± 0.85 ㎛ (n = 20), and the fertilized egg envelope consisted of three layers, an outer adhesive electron-dense layer, a middle layer with low electron density and an inner electron-dense layer with grooves in counter structure from other most teleost. Collectively, these morphological characteristics and adhesive property of fertilized egg, and ultrastructures of micropyle, outer surface, and section of fertilized egg envelope are showed species specificity.

Assessment of Genetic Diversity of Hedera spp. Using RAPD Marker Technique (RAPD Marker를 이용한 Hedera속 식물의 다양성 조사)

  • Jung, Mi Soon;Joung, Youn Hwa;Lee, Ja Hyun;Choi, Jeong Keun;Kim, Kwang Soo;Han, Tae Ho
    • FLOWER RESEARCH JOURNAL
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    • v.16 no.1
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    • pp.28-35
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    • 2008
  • Eleven accessions of Hedera helix, three accessions of Hedera rhombea, one accession of Fatshedera lizei, and one accession of Fatsia japonica were collected and their genetic diversity was measured by using 10 RAPD primers. Approximately ninety seven percentage of polymorphism was detected, because broad germplasm, three genus, was used. Total 97 bands were scored and a dendrogram was constructed by using an UPGMA method. Accessions belonging to Hedera helix tightly clustered in one group: eight accessions showed extremely narrow genetic differences and the other three accessions also showed significant similarity. Despite of their genetic similarity, they showed morphological variations. The morphological variation with a narrow genetic differences indicated that the ivy cultivars have been indeed developed from a mutation breeding program. Genetically most unrelated Fatsia japonica showed a genetic distance of 0.63 on the average between other species. An accession from Fatshedera lizei developed by crossing between two genus, Hedera helix and Fatsia japonica, was allocated together with accessions from Hedera rhombea.