• Korean Journal of Plant Taxonomy
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• v.43 no.3
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• pp.208-222
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• 2013

In this paper, we conducted the taxonomic study of the tribe Epilobieae Endl. and concluded that a total of nine taxa, including one Chamerion (Raf.) Raf. ex Holub and eight Epilobium L., exist in Korea. Although C. angustifolium subsp. angustifolium has been placed traditionally either in Epilobium or Chamaenerion, it can be clearly distinguished from the species of Epilobium by having alternate leaves, slightly zygomorphic flowers, non-clefted petals, and equal length of 8 stamens, supporting the recognition of genus Chamerion. All but one species of Epilobium, E. platystigmatosum, was investigated for the surface of seeds using scanning electron microscope (SEM). The seed sculpture of Korean Epilobium can be classified into three types, i.e., papillose, reticulate, and ridged. E. ciliatum subsp. ciliatum is the only species Epilobium, which has the ridged seed sculpture. E. amurense subsp. cephalostigma can be distinguished from conspecific E. amurense subsp. amurense based on leaf shape, trichome shape and distribution, size and habit. Both E. fastigiatoramosum and E. palustre have entire leaf margins, but they can be distinguished based on leaf shape, stigma, and seed sculpture; the former has elongated elliptic leaves, capitate stigma, ridged seed sculpture, whereas the latter one has elongated lanceolate leaves, club-shaped stigma, and reticulate seed sculpture. Finally, we report the first record of E. platystigmatosum in Korea, and further comparative study including conspecific populations from Japan and China can clarify the occurrence of this taxon in Korea.

• Korean Journal of Environmental Biology
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• v.37 no.2
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• pp.119-128
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• 2019

The morphological characteristics of the bloom-forming dinoflagellate Akashiwo sanguinea isolated from Jangmok Harbour, Geoje in Korea was examined using light and scanning electron microscope (SEM), and its large subunit (LSU) rDNA was sequenced. Additionally, investigation was done on the effects of temperature and salinity on the growth of A. sanguinea. The cells were dorso-ventrally compressed up to 54.7-70.3 ㎛ long and 31.5-48.5 ㎛ wide. The epicone was conical while the hypocone was separated into two lobes. The nucleus was positioned at the center of the cell. The yellow-brown chloroplasts radiated close to the cell center. SEM observation indicated that A. sanguinea has an e-shaped apical groove. Molecular phylogeny based on LSU rDNA gene sequences revealed that the A. sanguinea strains isolated from Jangmok Harbor were classified in the clade of ribotype A. The maximum growth rate (0.50 day^-1) was observed at 20℃ and 20 psu, while the maximum cell density (1,372 cells mL^-1) was observed at 25℃ and 30 psu. This indicates that the blooms of A. sanguinea ribotype A in Korean coastal area are affected by water temperature, rather than the salinity.

• Journal of Periodontal and Implant Science
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• v.27 no.4
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• pp.829-844
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• 1997

Dentin hypersensitivity must be one of the most frequent postoperative complaints in periodontal patients. Obliterating the open dentinal tubules or decreasing the diameter of their orifices would, therefore, be an objective of treatment for hypersensitive teeth. The purpose of this study was to evaluate the effect of a pulsed Nd:YAG laser irradiation on obliteration of dentinal tubules and to determine any difference according to irradiation methods. The 45 posterior teeth that had been extracted due to periodontal disease were initially treated with tetracycline HCI(100 mg/ml, 4 min.) to remove the smear layer after root planing. The root surfaces were then irradiated by a pulsed Nd:YAG laser(EL.EN.EN060, Italy) by different laser beam spot size and different exposure condition: ${\cdot}$ group 1: irradiated group by small spot(beam diameter=1mm, lW, 2 sec) ${\cdot}$ group 2: irradiated group by large spot(beam diameter=10mm, 1W, 200 sec) ${\cdot}$ group 3: irradiated group by gradual increase of watt (from 0.3W to 1.0W), beam diameter=4mm ${\cdot}$ group 4: irradiated group by fixed watt(1.0 W), beam diameter=4mm ${\cdot}$ control group: no irradiation but root planing and tetracycline HCI conditioning only. Additionally, the specimens were retreated with tetracycline HCI(100mg/ml, 4min.) to evaluate the stability of obliteration effect by Nd:YAG laser. Specimens were examined under the scanning electron microscope(JEOL, JSM-840A, Japan). Photomicrographs were taken at ${\times}4,000$ magnification and were analyzed statistically. The results were as follows: l. Scanning electron micrographs of root surface treated by tetracycline HCI alone(control group) showed widened, funnel-shaped dentinal tubules, while those of the root surface irradiated by various methods showed partially or completely obliterated dentinal tubules and various surface alterations, eg, flat, multiple pitted, melted and resolidified surface at the same energy density. 2. There was no significant difference in the obliteration effect of dentinal tubules between group 1 and group 2, and between group 3 and group 4(p>0.05). 3. The obliteration effect of dentinal tubules by a Nd:YAG laser irradiation was relatively stable to tetracycline HCI. The results demonstrate that a pulsed Nd:YAG laser irradiation within 1.0W, regardless of irradiation methods, can obliterate dentinal tubules effectively.

• Research in Plant Disease
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• v.15 no.3
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• pp.209-216
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• 2009

During the period of June, 2005 to May, 2008, 44 host plants infected with powdery mildew were collected in the Jeon-ju and Jang-su districts of Jeonbuk province and in the Jang-sung district of Jeonnam province. The hyperparasites, Ampelomyces were confirmed in 12 plant species. Most of the pycnidium shapes of Ampelomyces were circular or oval shaped, and the sizes were different even within the same host plant, and also the color of pycnidium was ranged from light brown to dark brown. Ampelomyces species were isolated from 4 hosts including Impatiens balsamina L., Cucurbita pepo, Rudbeckia laciniata var. elatier and Youngia sonchifolia, and thus the most appropriate 12 Ampelomyces strains for the current experiment were selected. When analyzing the selected 12 strains' incubational and nutritional characteristics, the malt extract agar was the most appropriate media. When investigating the effect of osmotic pressure on the spore germination, 0.15M NaCl concentration was the optimum germination concentration. When the isolated Ampelomyces sp. was tested in-vitro, it was found to be effective to control in other plant pathogens, isolated Ampelomyces showed no pathogenicity to the plant. strains isolated . studied on rDNA ITS sequence analysis. The rDNA ITS sequence data of Ampelomyces sp. isolate BSLAH16 from Impatiens balsamina L. were analyzed and identified.

• Economic and Environmental Geology
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• v.29 no.4
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• pp.421-428
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• 1996

The occurrence, optical property, chemical composition, crystal structure and formation environments of the phillipsite within deep-sea manganese nodules were systematically investigated in this study. Phillipsite in manganese nodules occurs in nucleus of nodules along with consolidated bottom sediments, weathered volcanic debris, and interstitial grains in the each layer of manganese encrusts. Phillipsite is predominantly pseudomorphs of volcanic shards, and occurs as white to pale yellow in color lath-shaped and equant crystals. These show aggregations of prismatic, blocky, and bladed of 2 to $20{\mu}m$ long, and 2 to $5{\mu}m$ thick. The simplified average chemical formula of phillipsite is $({Ca_{0.1}Mg_{0.3}Na_{1.1}K_{1.5}})_3{(Fe_{0.3}Al_{4.2}Si_{11.8})O_{32}{\cdot}10H_2O}$ with a very siliceous and alkalic. The $Si/(Al+Fe^{+3})$ ratio is 2.37 to 2.78 and alkalis greatly exceed the divalent exchangeable cations, and Na/K ratio is 0.59 to 0.81. The phillipsite is monoclinic ($P2_l/m$) with the unit-cell parameters, $a=10.005{\AA}$, $b=14.129{\AA}$, $c=8.686{\AA}$, ${\beta}=124.35^{\circ}$, and $V=1013.6{\AA}^3$. Phillipsites in manganese nodules formed apparently authigenically at a temperature less than $10^{\circ}C$, and they crystallized at a pressure of less than 0.7 kb, and pH of about 8 in deep-sea environments.

• Applied Microscopy
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• v.27 no.1
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• pp.71-86
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• 1997

The regeneration and differentiation of the cutaneous pigment system in the goldfish, Carassius auratus during the wound healing process were studied with high magnification electron microscope. The cutaneous pigment cells of the normal tissues were composed of three kinds of dermal chromatophores-xanthophores, leucoiphores and melanophores. While xanthophores contain two kinds of pigment granules-pterinosomes and carotenoid vesicles, leucophores and melanophores contain amorphous pigment granules (leucosomes) and oval shaped electron dense melanin pigment granules (melanosomes) respectively. After injury, primary wound healing responses being carried out by migration of epidermal cells and hemocytes spreading over the wound surface at the day of wounding. And at the time of primary wound closure, 5 to 7 days after wounding, rER rich cells-presumably common precursors of dermal chromatophores-immigrated into the wound area. First redifferentiated chromatophores appeared 3 weeks after wounding. Pigment granules of the chromatophores were emerged from the cytoplasmic Golgi complex via rough endoplasmic reticulum. Pinocytotic vesicles which associated with accumulation of pigment material, appeared only at the inner surface of the chromatophores adhering to the rER rich cells, characteristically. The differentiation of each chromatophore in addition to integumental wound repair were accomplished within 4 weeks after wounding at most cases, however the total numbers and densities of these repaired chromatophores still primitive state. Moreover, It has been revealed that complete repair of chromatophores at wounded tissues from burns requirs more than 3 months in normal environment.

• Journal of Life Science
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• v.23 no.3
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• pp.341-346
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• 2013

The disappearance of seaweed flora in some rocky areas, which is known as algal whitening, barren ground, coralline flats, or deforested areas, is associated with some species of coralline algae. To determine the biological characteristics of a representative species of crustose coralline alga, the 18S rDNA gene was sequenced to identify the genus Lithophyllum. According to its morphological and distributional characteristics, it was deduced to be L. yessoense. Viability was measured using triphenyl tetrazolium chloride and showed high viability from December to February. Culture conditions of $16^{\circ}C$, a 16 hr light, 8 hr dark cycle, and 30 ${\mu}E/m^2/s$ light intensity were optimal for maintaining the viability of the alga for up to five days. Included in the fatty acids was 9.7% ${\omega}$-3 eicosapentaenoic acid. An electron microscopy scan of the surface structure revealed round craters about 3.6 ${\mu}m$ in diameter, which were covered with rough, irregular, and angular polygon-shaped structures about 1.0 to 3.7 ${\mu}m$ in size. Based on the composition and structure found in our study, biomimetic coralline alga might become an environmentally friendly antifouling material against the attachment of soft foulants.

• The Korean Journal of Physiology and Pharmacology
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• v.11 no.5
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• pp.175-182
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• 2007

Members of prostaglandin(PG) E-series elicit cellular effects mainly through adenylyl cyclase-cAMP signaling. The role of $PGE_2$-induced increase in cAMP has been shown to be compartmentalized in the cardiac myocytes: $PGE_2$-induced increase of cAMP is not involved in the control of cardiomyocytic contraction. The purpose of the present study was to define the effect of $PGE_1$ on the cGMP levels and the role of $PGE_1$ in the atrial secretory function. Experiments were performed in perfused beating rabbit atria and atrial contractile responses, cGMP and cAMP efflux, and atrial natriuretic peptide(ANP) secretion were measured. $PGE_1$ increased cGMP as well as cAMP efflux concentration in a concentration-dependent manner, however, no significant changes in atrial secretory responses were observed(with $1.0{\mu}M\;PGE_1$; for cGMP, $144.76{\pm}37.5%$, n=11 versus $-16.81{\pm}4.76%$, n=6, control, p<0.01; for cAMP, $187.60{\pm}41.52%$, n=11 versus $7.38{\pm}19.44%$, n=6, control, p<0.01). $PGE_1$ decreased atrial dynamics slightly but transiently, whereas $PGE_2$ showed similar effects but with lower potency. Isoproterenol increased atrial cAMP efflux(with 2.0 nM; $145.71{\pm}41.89$, n=5 versus $7.38{\pm}19.44%$, n=6, control, p<0.05) and mechanical dynamics and decreased ANP secretion. The $PGE_1$-induced increase in cGMP efflux showed a bell-shaped concentration-response curve. $PGE_1$-induced increase of cGMP efflux was not observed in the presence of L-NAME, an inhibitor of nitric oxide(NO) synthase, or ODQ, an inhibitor of NO-sensitive guanylyl cyclase. L-NAME and ODQ showed no significant effect on the $PGE_1$-induced transient decrease of atrial dynamics. These data indicate that $PGE_1$ increases cGMP levels via NO-soluble GC signaling in the cardiac atrium and also show that $PGE_1$-induced increases in cGMP and cAMP levels are not involved in the regulation of atrial secretory and contractile functions.

• Restorative Dentistry and Endodontics
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• v.30 no.2
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• pp.95-101
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• 2005

The aim of this study was to evaluate the microleakage of teeth according to root canal preparation with & without apical enlargement in various size of apical foramen. 60 extracted one canal roots were cross-cutted at 5 mm from root apex and divided into two groups according to their apical foramen size of large (L) and small (S). Each group was subdivided into two groups accordance with their cross-sectional configuration at 5 mm from apex, round (R) and ovoid (O); SR Group, SO Group LR Group, LO Group. Each group was shaped in .02 taper by Quantec series Nickel-Titanium (NiTi) rotary file, obturated by lateral condensation method. Leakage was measured using a fluid transport model under 40 $cmH_2O$ pressure. After the leakage test, blocks which had showed the leakage retreated with .04 taper and ,06 taper and evaluated the degree of fluid filtration in each group. The data was analysed statistically using chi-square test and fisher's exact test. The results obtained were as follows : 1. Significant difference in leakage was found in groups which had different apical foramen size in .02 taper instrumentation (p < 0.05), but not in .04 taper instrumentation (p > 0.05) 2. The difference in microleakage according to the shape of canal was not evident at 5 mm from apex (p > 0.05). 3. There was correlation between .02 taper instrumentation and .04 taper instrumentation in LR group, LO group (p < 0.05).

• International Commerce and Information Review
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• v.15 no.4
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• pp.241-265
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• 2013

The purpose of this paper is to examine the Banks's Examination of Documents in the L/C Transactions. Most of all, this article deals with one of most important aspects of the law on documentary credits, namely, the compliance of documents presented with the terms and conditions of a letter of credit. In addition, the general principles of strict compliance will be considered and in the next, the requirements of specific documents such as invoices, transport documents and insurance policies. This area of letter of credit law is shaped not only by judge-made decisions but also the articles of Uniform Customs and Practice for Documentary Credits, the International Standard Banking Practice(ISBP Publication No.745) prepared by the Banking Committee of the International Chamber of Commerce as well as the position papers and opinions of the latter. Whether a document complies with the terms of a letter of credit is essentially a matter of examination and construction of the document in question against the terms of the letter of credit under which it is presented, articles of the UCP, ISBP as well as the opinions and statements of the Banking Committee. Most of all this article was focused on provisions of UCP600. Comparison with provisions of UCP500 have been drawn where appropriate.