• Journal of Powder Materials
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• v.8 no.4
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• pp.258-267
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• 2001

In this work, the conventional transient liquid phase(TLP) bonding was modified. An attempt was made of using a liquid phase sintered alloy, which will be a liquid phase coexisting with a solid phase at the bonding temperature, as an interlayer for bonding metals. With an aim of revealing the fundamental features of this modified TLP bonding, the kinetics concerned with the growth of solid particles and the isothermal solidification process in Fe-1.16wt%B and Fe-4.5wt%P interlayers for the bonding pure iron, as well as the morphological change of the solid particle, were investigated.

• Applied Microscopy
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• v.28 no.4
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• pp.503-512
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• 1998

Fine structure of the cutaneous pigments in the black widow spider, Latrodectus mactans are studied with light and electron microscopes. The cutaneous pigments are only observed in epidermal layer just beneath the cuticle. These pigments are compactly distributed around the spinnerets which located at caudal area of the abdomen. According to the fine structural characteristics of the pigment granules, two main types of guanine pigment granules-carotenoid vesicles and reflecting platelets - are observed in the cytoplasm of the epidermal cells. Morphological features of these pigment granules are characterized as the electron dense carotenoid vesicles and the electron lucent reflecting platelets. Marginal electron density of the carotenoid vesicle is different from that of internal region, whereas the reflecting platelets have laminated crystalline granules. Typiral structures of these pigment granules are very similar to those of invertebrate's chromatophores, especially erythrophores and iridophores. Moreover differentiation of these pigment granules are also originated from the small vesicles of Golgi complexes similarly to those of cutaneous chromatophores.

• Animal Systematics, Evolution and Diversity
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• v.25 no.3
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• pp.269-273
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• 2009

On 28 April 2008, a male Himalayan Swiftlet (Aerodramus brevirostris) was captured and examined at a night roost of swallows on Hongdo Island, Jeollanam-do, Korea. This is the first record of this species from Korea confirmed by specimen examination. We describe morphological features and some phylogenetic notes of the Himalayan Swiftlet found.

• Korean Journal of Veterinary Research
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• v.21 no.1
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• pp.7-10
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• 1981

During the studies on the esophagogastric ulcers in swine, Anisakis type larvae were found associated with stomach lesions. 1. Of the 1,531 pigs examined, 11(0.7%) were infested with the parasite in the stomach. 2. The parasite was identified as Anisakis type I larvae, according to the morphological characteristics. 3. On gross examination, the parasites were seen penetrating gastric mucosa, resulting in hemorrhagic ulcers. 4. Main histopathological features were edema, massive eosinophilic infiltrations around the parasite, necrosis and perivascular eosinophilic accumulations in the submucosa.

• Journal of Microbiology
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• v.35 no.3
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• pp.222-227
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• 1997

DNA fragments homologous to chitin synthase gene were amplified from the genomic DNA of Beauveria brongniartii by PCR using degenerate primers. Cloning and sequencing of the PCR-amplified fragments led to the identification of a gene, designated BbCHSl. Comparison of the deduced amino acid sequence of BbCHSl with those of other Euascomycetes revealed that BbCHSl is a gene for class II chitin synthase. The Blastp search of the deduced amino acid sequence of BbCHSl displayed the highest rate of similarity, 95.8%, with CHS2 of Metarhizium unisopliae. Phylogenetic analysis of the amino acid sequences confirmed the taxonomic and evolutionary position of B. brongniartii, which was previously derived by traditional fungal classification based on morphological features.

• Journal of Life Science
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• v.10 no.2
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• pp.17-20
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• 2000

Adenovirus which is an important infectious viral agent in respiratory and alimentary tract was investigated in Pusan, 1999. Fifteen cases of adenovirus were detected from stools and throat swabs of suspected patients. Two cases of enteric adenovirus were detected from a 5 years old boy and a 6-month-old boy. Thirteen cases of respiratory adenoviruses were detected from children aged under 10 years old and one adult. From respiratory specimens, 1 case of adenovirus type 2, 1 case of type 5, and 11 cases of type 3 were found. Enterotype 41 was detected from fecal preparations. Adenoviruses appeared mostly during winter months, January, February and December. Adenovirus showed a slowly progressive cytopathic effect on HEp-2 cells, Vero cells and BGM cells at 37$^{\circ}C$, in a 5-7% $CO_{2}$ incubation. An electron microscopic observation exhibited non-enveloped icosahedron with a diameter of 70nm. No significant differences on cytopathic effect and morphological features have been found from specimens of either alimentary tract or respiratory secretions.

• Food Science and Biotechnology
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• v.17 no.6
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• pp.1305-1309
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• 2008

Baicalein, one of the major flavonoid in Scutellaria baicalensis, has been known for its effects on proliferation and apoptosis of many tumor cell lines. Most biological effects of baicalein are thought to be from its antioxidant and prooxidant activities. In this report, baicalein was found to induce apoptosis in HL60 human promyelocytic leukemia cell line. Baicalein treatment induced DNA fragmentation and typical morphological features of apoptosis. To elucidate the mechanism of baicalein-induced apoptosis, the activities of the members of caspase family were measured. Interestingly caspase 2, 3, and 6 were significantly activated whereas caspase 1, 8, and 9 were not activated, suggesting selective involvement of specific caspases. Further, treatment with caspase inhibitors also supports the involvement of caspase 2 in apoptosis process. Although it has been reported that baicalein can induce apoptosis through many caspase pathways, the present study indicates that caspase 2 not caspase 9 pathway may be the important step in apoptosis on HL60 cell line.

• Korean Journal of Environmental Biology
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• v.35 no.4
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• pp.521-525
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• 2017

A marine algal species belonging to Gigartinales was collected from Geoje, Korea. This shares the generic features of Ahnfeltiopsis, such as multiaxial thalli with a compact and pseudoparenchymatous medulla, densely cytoplasmic secondary medullary cells around immersed cystocarps with a carpostome, and is distinct from similar species within the genus by a combined feature of small (up to 4 cm tall) and tuft thalli, compressed to subcompressed branches except for ultimate branchlets and base of main axes, cartilaginous in texture, dichotomous branches, rarely produced proliferations, absence of hypha-like filament in the medulla and internal cystocarps with a carpostome. In phylogenetic tree based on rbcL sequence, the Korean species nests in the same clade with Ahnfeltiopsis linearis. The genetic distance between both sequences within the clade was 1.5%, considered to be within the intra-species range for the genus. This morphological and molecular evidence confirms the Korean alga to be identified as A. linearis originally described from California. This is the first record of A. linearis in Korea.

• The Korean Journal of Malacology
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• v.27 no.2
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• pp.91-97
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• 2011

This study examines the morphological features of larval and postlarval shells of the paedomorphic bivalve Crenella decussata Montagu, 1808 from the Sea of Japan. During the early morphogenesis of the shell of C. decussata the following characteristics appear: prodissoconch I -the anterior and posterior provincular teeth, a broad primary ligament pit located on the chondrophore; nepioconch - the anterior and posterior juvenile teeth,primary lateral teeth, fine commarginal and radial sculpture. Larvae of C. decussata distinctly differ from other mytilid larvae by a D-shaped shell, absence of umbo, astraight hinge margin, and homogeneous fine-grained sculpture without co-marginal lines of growth. These shell characters indicate lecithotrophic development of this species. Some morphostructures are revealed which might be used in crenellin taxonomy.

• The Korean Journal of Mycology
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• v.49 no.2
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• pp.175-181
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• 2021

A fungal strain was isolated from a soil sample collected in Korea and designated as YW23-8. Based on a sequence analysis of the internal transcribed spacer (ITS) regions, the isolate was assigned to the genus Sarcopodium. Moreover, a phylogenetic analysis based on the concatenated nucleotide sequences of the ITS regions and the large subunit of the nuclear ribosomal RNA (LSU) gene showed that the strain YW23-8 occupies a distinct phylogenetic position within Sarcopodium. The isolate had significant differences from its closest neighbors, S. circinosetiferum, S. circinatum, S. macalpinei, and S. vanillae. Morphological features such as different conidial structures, the absence of septation in conidia, and the presence of milky white watery droplets along with the results of the phylogenetic analysis clearly distinguish YW23-8 from the closest Sarcopodium species. We therefore conclude that strain YW23-8 represents a novel species of the genus Sarcopodium for which we propose the name Sarcopodium terrigenum.