• The Korean Journal of Zoology
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• v.38 no.3
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• pp.330-339
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• 1995

In Helice tridens tridens, hylaine cells, small granulocytes, and large granulocytes were identified. Features of hyaline cells include a large nucleus in proportion to the cytoiplasm, and weak electron-dense granules of oval shape and vesicles, and endoplasmic reticulum (ER) in the cytoplasm. Small granulocytes have smaller nucleus than that of the hyaline cells, well-developed ER, Golgi complex, and small, round and electron-dense granules in the cytoplasm. Large granulocytes contain large and electron dense granules (ahout 1 $\mu$m) that fused small granules. Hemocytes of Helice tridens tridens differentiated from hyaline cell to large granulocyte granules of hyaline cells have lysosome and make small vesicles from nuclear envelopes. While these vesicles pass through the Golgi complex, they are filled with electron dense matetials, and then fused with the small granules. They eventually matured into large granules. All of hemocytes have the glycogen particles. In the large granulocytes heterogeneouse granules were supposed to occur by disappearance of granules.

• Plant Resources
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• v.5 no.1
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• pp.59-69
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• 2002

Twenty-three plants of Japanese apricot (Prunus mume) were collected from several sites around Mountains JIRI in Korea. Japanese apricots having the different morphological features were evenly distributed in the groups made from the cluster analysis, indicating no geographic distributions but artificial vegetations in Korea. Japanese apricots were, as based on the PCR-RAPD techniques, clustered into the three groups; a group (prototype) having the five white petals with the five red sepals, a group (green type) having the five white petals with the five green sepals, and a group (hybrid type) having the more than five red petals with various colored sepals. The prototype apricots showed higher toxicities than other type apricot against bacteria and production of less compounds in TLC plates. The polypetal types of Japanes apricot were related to those of p. armebiaca in the characteristics of seed (the ruggedness), but also to be closed to those of p. armebiaca in PCR-RAPD analysis. The cluster analysis of the twenty three apricots and its related species calculated from the two primers were shown to distinguish relationships of cultivars within species, or of individual plants within cultivars, but also to display the two overlapping bands resulted from PCR-RAPD technique.

• Mycobiology
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• v.41 no.4
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• pp.191-201
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• 2013

Distinguishing individual Russula species has been difficult due to extensive phenotypic plasticity and obscure morphological and anatomical discontinuities. Due to highly similar macroscopic features, such as the presence of a red-cap, species identification within the Russula subgenus Amoenula is particularly difficult. Three species of the subgenus Amoneula have been reported in Korea. We used a combination of morphology and three molecular markers, the internal transcribed spacer (ITS), 28S nuclear ribosomal large subunit (LSU), and RNA polymerase II gene (RPB2), for identification and study of the genetic diversity of Russula subgenus Amoenula in Korea. We identified only two species in Korea (R. mariae and R. violeipes); these two species were indistinguishable according to morphology and LSU, but were found to be reciprocally monophyletic species using ITS and RPB2. The markers, ITS, LSU, and RPB2, have been tested in the past for use as DNA barcoding markers, and findings of our study suggest that ITS and RPB2 had the best performance for the Russula subgenus Amoneula.

• Journal of Species Research
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• v.1 no.2
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• pp.232-239
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• 2012

Taxonomy of umbelliferous taxa Heracleum moellendorffii complex has been unclear in their species delimitation in the far-eastern Asian regions. In both Korea and China Heracleum moellendorffii was adopted for their description while H. sphondylium was chosen to describe Japanese Heracleum. From Genbank accessions, taxa collected from Kamtchatka and Promorskiy, Russia were defined as H. maximum, endemic taxon to North America. In this study, we reviewed the taxonomy of Heracleum moellendorffii complex in Korea and neighboring countries on the basis of molecular phylogenies derived from sequences of nuclear ribosomal DNA internal transcribed spacer (ITS) regions. From three Korean accessions of Heracleum investigated in this study, two types of ITS sequences were obtained; two accessions were related to Chinese H. moellendorffii var. moellendorffii and North American H. maximum without forming a clade while the other one was identical to accession from H. maximum from Primorskiy, Russia. In the other hand, Japanese H. moellendorffii (=H. sphondylium ssp. sphondylium var. nipponicum in the flora of Japan) was closely related to H. maximum accessions from Korea and Russia, not nested within the clade comprising several subspecies of H. sphondylium. In order to delimit species boundaries among putatively closely related Heracleum species in fareastern Asian countries, more samples and much more rapidly evolved DNA regions must be investigated with interpretation of morphological and anatomical features.

• Journal of Powder Materials
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• v.25 no.5
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• pp.379-383
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• 2018

Silica is used in shell materials to minimize oxidation and aggregation of nanoparticles. Particularly, porous silica has gained attention because of its performance in adsorption, catalysis, and medical applications. In this study, to investigate the effect of the density of the silica coating layer on the color of the pigment, we arbitrarily change the structure of a silica layer using an etchant. We use NaOH or $NH_4OH$ to etch the silica coating layer. First, we synthesize ${\alpha}-FeOOH$ for a length of 400 nm and coat it with TEOS to fabricate particles with a 50 nm coating layer. The coating thickness is then adjusted to 30-40 nm by etching the silica layer for 5 h. Four different shapes of ${\alpha}-FeOOH$ with different colors are measured using UV-vis light. From the color changes of the four different shapes of ${\alpha}-FeOOH$ features during coating or etching, the $L^*$ value is observed to increase and brighten the overall color, and the $b^*$ value increases to impart a clear yellow color to the pigment. The brightest yellow color was that coated with silica; if the sample is etched with NaOH or $NH_4OH$, the $b^*$ value can be controlled to study the yellow colors.

• Journal of Microbiology and Biotechnology
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• v.24 no.1
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• pp.1-7
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• 2014

The possibility of using hyphomycete fungi as suitable biocontrol agents against greenhouse whitefly has led to the isolation of various insect pathogenic fungi. Among them is Beauveria bassiana, one of the most studied entomopathogenic fungi. The objective of this study was to use B. bassiana M130 as an insecticidal agent against the greenhouse whitefly. M130 isolated from infected insects is known to be a biocontrol agent against greenhouse whitefly. Phylogenetic classification of M130 was determined according to its morphological features and 18S rRNA sequence analysis. M130 was identified as B. bassiana M130 and showed chitinase (342.28 units/ml) and protease (461.70 units/ml) activities, which were involved in the invasion of the host through the outer cuticle layer, thus killing them. The insecticidal activity was 55.2% in petri-dish test, 84.6% in pot test, and 45.3% in field test. The results of this study indicate that B. bassiana has potential as a biological agent for the control of greenhouse whitefly to replace chemical pesticides.

• Journal of Microbiology and Biotechnology
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• v.23 no.7
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• pp.1031-1040
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• 2013

Candida albicans is a dimorphic fungus that commensally colonizes human mucosal surfaces. The aim of this study was to assess the role of different C. albicans morphologies in inducing pattern recognition receptors (PRRs) and cytokines in macrophages. Macrophages may respond to pathogen-associated molecular patterns via TLR2 and TLR4 by expressing cytokines. The hyphal transition of C. albicans was induced by 20% serum (S), RPMI-1640 (R), or $39^{\circ}C$ culture (H). Macrophages were then challenged with either yeast (Y) or different hyphae cultures of C. albicans, followed by RT-PCR and FACS analysis of PRRs expression. In addition, macrophages were stimulated with either yeast or different hyphae cultures of C. albicans used by RT-PCR and Bio-Plex analysis of cytokines production. Macrophages expressed high levels of TLR4 and dectin-1 after stimulation with Y cells. In contrast, stimulation with H or R cells strongly increased the expression of TLR2 and dectin-2. Stimulation with Y cells significantly enhanced the expression of IL-$1{\beta}$ and weakly increased the expression of IL-6 and IL-12. Stimulation with hyphal cells (S, R, and H) strongly increased IL-10 expression, but weakly reduced IL-$1{\beta}$ expression. The phagocytosis activity and NO production of macrophages were decreased upon treatment with hyphal cells compared with yeast, and depended on the length of hyphae. In summary, the yeast and hyphae forms of C. albicans resulted in an induction of different PRRs, with accompanying differences in immune cell cytokine profiles.

• Korean Journal of Plant Taxonomy
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• v.33 no.4
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• pp.435-454
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• 2003

The morphology of plants and scanning electro-microscopical features of fruits were examined to evaluate the taxonomic entities of Korean Adonis L. in sensu lato (Ranunculaceae). The species of Korean Adonis were readily diagnosed by the branching pattern of stem, the number of flowers, the bifurcation of leaf main axis, the number of tepals, the flowering periods in relation to leaf sprouting, and the number of stomata and the texture of fruit surface. This study demonstrates that there are three species, A. amurensis, A. pseudoamurensis, and A. multiflora., found in Korea. However, A. ramosa, which has been often claimed to be distributed in Korea, is not present in Korea.

• Journal of the Institute of Electronics Engineers of Korea CI
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• v.41 no.3
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• pp.115-124
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• 2004

The content-based retrieval using low-level features can hardly provide the retrieval result that corresponds with conceptual demand of user for intelligent retrieval. Video includes not only moving picture data, but also audio or closed-caption data. Knowledge-based video retrieval is able to provide the retrieval result that corresponds with conceptual demand of user because of performing automatic indexing with such a variety data. In this paper, we present the knowledge-based video retrieval system using Korean closed-caption. The closed-caption is indexed by Korean keyword extraction system including the morphological analysis process. As a result, we are able to retrieve the video by using keyword from the indexing database. In the experiment, we have applied the proposed method to news video with closed-caption generated by Korean stenographic system, and have empirically confirmed that the proposed method provides the retrieval result that corresponds with more meaningful conceptual demand of user.

• Preventive Nutrition and Food Science
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• v.8 no.2
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• pp.113-118
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• 2003

We recently extracted lignans such as matairesinol and 2-hydroxyarctigenin from safflower seeds and found that they exhibit a potent cytotoxic effect on human promyleocytic leukemia HL-60 cells. In this study, we investigated whether mechanisms of the matairesinol-induced cell death are associated with the programmed cell death, apoptosis. Matairesinol dose-dependently reduced viability of HL-60 cells with an IC/sun 50/ value of 60 $\mu$M. Staining of cells with Hoechst 33342 revealed distinct morphological features of apoptosis, such as the nuclei broken into chromatin containing fragments of various sizes in the cells exposed to 100 $\mu$M matairesinol for 24 hr. Agarose gel electrophoresis of DNA from the cells treated with matairesinol showed internucleosomal DNA degradation into oligonucleosomal sizes. DNA ladder like patterns were easily detected after treatment with matairesinol concentrations ranging from 10 to 100 $\mu$M after 24 hr. In cells treated with 100 $\mu$M matairesinol for differing time periods, the DNA ladder was detectable from 6 hr onward. A time course histogram of the DNA content analyzed by flow cytometry revealed a rapid increase in subdiploid cells and a concomitant decrease in diploid cells exposed to 100 $\mu$M matairesinol. These results indicate that matairesinol-induced HL-60 cell death was due to the DNA damage and apoptosis.