• Biomedical Science Letters
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• v.8 no.2
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• pp.83-88
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• 2002

To investigate the skin toxicity of xylene, xylene (25 mg/$\textrm{cm}^2$) has been sequentially applied to the rat skin for four days. On the light microscopic examination, epithelium was left out with infiltration of inflammatory cells in border with dermis, and formation of new epithelial layer was shown under the inflammatory zone. Application of xylene to the rat skin showed the marked rise of cutaneous xanthine oxidase activity whereas, He activities of oxygen free radical scavenging enzymes, superoxide dismutase and glutathione S-transferase, were significantly declined. Furthermore, the content of cutaneous glutathione was more and less decreased in rat skin applied with xylene. In conclusion, these results suggest that a part of oxygen free radical may be responsible for morphological changes in skin by applying xylene to the rat skin.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 1997.04a
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• pp.224-231
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• 1997

Microscopic examination for the morphological estimation of wear debris on the oil-lubrcated moving system is an accepted method for machine condition and fault diagnosis. However wear particle anaysis has not been widely accepted industry because it is dependent on expert interpretation of particle morphology and relies on subjective assessment criteria. This paper was undertaken to estimate the morphology of wear debris on the oil-lubricated movig system by computer image analysis. The wear test was performed under different sliding conditions using a wear test device made in our laboratory and wear testing specimen of the pin-on-disk-type was rubbed in pararline series base oil. In order to describe characteristics of debris of various shape and size, four shape parameters (50% volumetric diameter, aspect, roundness and reflectivity) have been developed and outlined in the paper. A system using such techniques promises to obviate the need for subjective, human interpretation of particle morphology in machine condition monitoring.

• Journal of Species Research
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• v.2 no.1
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• pp.7-14
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• 2013

During a systematic study on Korean nudibranchs, two phyllidiid and two polycerid species were collected and identified with examination of their external morphological characters. As a result of the study, two phyllidiid species, Phyllidia ocellata Cuvier, 1804 and Phyllidiella pustulosa (Cuvier, 1804) were redescribed since there was no descriptions of these species with Korean specimens. And two polycerid species, Thecacera pennigera (Montagu, 1815) and Triopha catalinae (Cooper, 1863) were described as new to Korean fauna. Diagnostic characters of these species are described with illustrations in this study. DNA barcode data from three species examined were also provided for a supplement to morphological identifications.

• International Journal of Industrial Entomology and Biomaterials
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• v.43 no.1
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• pp.6-15
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• 2021

We investigated the taxonomic status of the Korean populations of Eurema hecabe (Linnaeus, 1758) based on morphology and nuclear triose phosphate isomerase (Tpi). Up to now, the Korean population of E. hecabe was classified into E. mandarina (de l'Orza, 1869) based on morphological characteristics. A previous study raised the possibility of the Jeju-do population to be E. hecabe based on the color of forewing's fringe. However, morphological examination showed that the Korean population found in southern areas (Gyeonsang and Jeolla provinces), including Jeju-do is E. mandarina. In particular, the external morphology of autumn seasonal type of the Korean population was almost same as the Japanese mainland population, which is known as E. mandarina. Furthermore, sequence analysis of Tpi gene from nine individuals of E. mandarina collected in South Korean localities including Jeju-do clearly showed that all Korean specimens truly belong to E. mandarina.

• Animal Systematics, Evolution and Diversity
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• v.38 no.3
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• pp.144-147
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• 2022

The polychaete Scolelepis (Scolelepis) sagittaria was originally described from Japanese waters and subsequently reported from Korean waters. In this study, we determined for the first time the mitochondrial cytochrome c oxidase subunit I (COI), 16S ribosomal DNA (16S rDNA), and nuclear 18S ribosomal DNA (18S rDNA) sequences of Korean specimens of S. (S.) sagittaria. We also assessed intraspecific variation in the shape of the prostomium of this species based on an examination of 247 individuals. All materials were collected from intertidal sandy beaches of the Korea Strait. The molecular data and morphological observations reported herein will contribute to gaining a better understanding of the taxonomic relationships among members of the genus Scolelepis.

• Animal Systematics, Evolution and Diversity
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• v.37 no.3
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• pp.229-234
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• 2021

Scolelepis (Scolelepis) daphoinos is newly reported in Korean fauna. This species can be distinguished from its congeners by the following characteristics: the presence of reddish pigment patches on the posterior part of the prostomium, notopodial postchaetal lamellae that are partially fused to the branchiae, and the presence of only the bidentate hooded hooks. The morphological diagnosis and photographs of S. (S.) daphoinos are provided. The partial mitochondrial cytochrome c oxidase subunit I (COI), 16S ribosomal DNA(16S rDNA), and the nuclear 18S ribosomal DNA (18S rDNA) sequences from Korean specimens of S. (S.) daphoinos were determined. Species identification was supported by a comparison of DNA barcode sequences of COI and 16S rDNA with morphological examination from the specimens of type locality, China.

• Journal of Species Research
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• v.11 no.1
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• pp.22-28
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• 2022

Two crinoid specimens of genus Tropiometra were collected from Busan and Tongyeong by SCUBA diving on August 2010 and October 2011, respectively. The specimens were identified as Tropiometra macrodiscus (Hara, 1895), which belongs to the family Tropiometridae of superfamily Tropiometroidea. The genus Tropiometra AH Clark, 1907 comprises four species worldwide at present, and it has not been reported in Korea. Tropiometra macrodiscus was first described by Hara (1895) in Japan. It is difficult to distinguish T. macrodiscus from T. afra (Hartlaub, 1890), there has been confusion with examination of their phylogenetic positions in crinoid morphological classification. Despite this, T. macrodiscus can be distinguished from T. afra based on longer arms, stouter whole-body parts, magnificently larger numbers of cirrus, and numerous segments. The morphological characteristics of T. macrodiscus collected in Korea have been described, and DNA barcode region representing cytochrome c oxidase subunit I was obtained for its molecular phylogenetic analysis.

• Mycobiology
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• v.51 no.3
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• pp.122-138
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• 2023

Elsinoë are plant pathogenic fungi that cause scabs, spotted anthracnose, and some morphological distortions on various plants, including woody plants, economically important crops, and ornamental plants. Taxonomical reexamination of Elsinoë species in Japan has not yet been conducted based on the modern species criteria. In this study, several Japanese isolates were reexamine based on the morphological and molecular-phylogenetic analysis of the internal transcribed spacer region (ITS), large subunit gene (LSU)m and protein-coding gene such as RNA polymerase II subunit (rpb2) and Translation elongation factor 1-alpha (tef). Japanese isolates were divided into four clades and three new species, Elsinoë hydrangeae, E. sumire, and E. tanashiensis were proposed. One species, Sphaceloma akebiae, was transferred to the genus Elsinoë.

• The Korean Journal of Mycology
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• v.50 no.3
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• pp.243-248
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• 2022

In Japan and China, Podosphaera pseudofusca causes powdery mildew in Fatoua villosa. During a taxonomic revision of Korean powdery mildew fungi, isolates newly collected from F. villosa were studied. Through morphological examination and molecular phylogenetic analyses of the internal transcribed spacer region and large subunit gene of rDNA, the powdery mildew fungus was identified as Podosphaera xanthii. In this study, we propose the merging of P. pseudofusca sensu Braun into the P. xanthii complex. To the best of our knowledge, this is the first report of Podosphaera powdery mildew on F. villosa in Korea.

• Korean Journal of Environmental Biology
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• v.23 no.2 s.58
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• pp.184-190
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• 2005

A taxonomic survey of the dinoflagellate family Prorocentraceae Stein was conducted on 17 locations off the coast of Korea. This monograph is the result of the microscopic analyses. A total of eight species have been identified and described, of which Prorocentrum concavum Fukuyo is new record for Korea.