• Applied Microscopy
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• v.43 no.1
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• pp.14-20
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• 2013

The leopard danio, Danio rerio var. frankei is a spotted color morph of the zebrafish, Danio rerio caused by a pigment mutation. The structural differences of fertilized egg and egg envelope are poorly documented. To clarify this, we compared the fertilized egg morphology and ultrastructures of surface structures, the micropyle and the cross section of fertilized egg envelopes of zebrafish and leopard danio, variation species of zebrafish using a light and electron microscopes. Although the fertilized egg sizes were different, the external shapes of the fertilized eggs of two species couldn't be differentiated under the light microscope. The characteristics of fertilized eggs, such as a spherical shape, a non-adhesive quality and a large perivitelline space, were shown to be related to spawning habit. In ultrastructure of fertilized egg envelope, there is no morphological difference of micropyle between two species. By contrast, the ultrastructure and the numbers of knob-like structures and semihemisphere-like structures per unit area on the outer surface, and the number of lamellae of inner layer on the fertilized egg envelope section displayed definite species specificity. Collectively, our data indicate that the ultrastructure of fertilized egg envelope in the zebrafish could be differentiated by species variation.

• Language and Information
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• v.18 no.1
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• pp.1-32
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• 2014

This paper provides a corpus study on subjunctives in Korean in a way of comparative semantics. The whole arguments of this paper are bolstered by distributional evidence taken from naturally occurring bitexts (i.e. a bilingual corpus), in which one sentence in a language is aligned with one translation in the other language. Since previous studies regard past tense morphology as the main component to express irrealis and uncertainty, this paper accordingly checks out whether the past tense morpheme (e/a)ss in Korean is also responsible for conveying the meaning of subjunctives. My finding is that the past tense morpheme (e/a)ss is a sufficient condition for forming subjunctives in Korean. The current corpus study verifies that the past tense morpheme is not obligatorily used in present conditional counterfactuals in Korean, unlike English. Yet, if (e/a)ss is used and the antecedent denotes a present situation, the conditional sentence can only be interpreted as conveying counterfactuality. On the other hand, wish constructions in Korean, irrespective of the semantic tense, often contain the past tense morpheme. Hence, this work substantiates Iatridou (2000)'s theory of 'fake past tense' is applicable to Korean subjunctives. The present corpus study, additionally, reveals that a conditional marker telamyen is a component of expressing past counterfactuals in Korean.

• Environmental Engineering Research
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• v.23 no.2
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• pp.164-174
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• 2018

Corrosion of copper alloys (copper, bronze and brass) in soil was evaluated at ambient temperature using various methods such as electrochemical impedance spectroscopy (EIS), polarization curves and Scanning Electron Microscopy (SEM) coupled with Energy Dispersive Spectroscopy microanalysis measurements. Three equivalent circuits were separately used to interpret the obtained impedance spectra. The EIS measurements indicated that the polarization resistance of all electrodes increases with increasing the immersion time. SEM showed a presence of three layers of corrosion products with various composition and morphology covering each electrode. In addition, it was found that at 20% of moisture content the $R_p$ values and the current density of all electrodes in the studied soil give the following order: copper > bronze > brass. Good consistency between the data obtained from EIS and PP measurements was observed.

• Journal of the Korean Applied Science and Technology
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• v.26 no.2
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• pp.171-178
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• 2009

A comparative analysis of the hindered amine light stabilizers (HALS) and UV abosrber (UVA) and their respective photostabilizing effect on wood plastic composites (WPCs) are reported in this study. The influence of accelerated weathering on the mechanical properties of the composites and the microscopic morphology of a degraded layer on the cross section and the surface were studied. UV absorbers were more efficient at preventing composite lightening than was UV stabilizer. The amount of whitening decreased with the increase of photostabilizers. With the addition of a UV absorber (Tinuvin360), the tensile modulus and strength of the composites increased slightly. However, the addition of a light stabilizer (Tinuvin770) and a UV absorber decreased the tensile modulus and strength of the composites. After 250 and 500 hr exposure, tensile modulus and strength of the un stabilized and stabilized composites decreased. The tensile strength of UV absorber (Chimassorb81)-stabilized composites was significantly greater than that of control and light stabilizer (Tinuvin770)- and UV absorber (Tinuvin360)-stabilized composites. UV absorber-stabilized samples showed less whitening and photodegradation than control and light stabilizer-stabilized samples.

• The korean journal of orthodontics
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• v.23 no.1 s.40
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• pp.115-122
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• 1993

This study was undertaken to compare the activity of masticatory muscle between normal occlusion and anterior openbite. 33 subjects without the experience of orthodontic treatment, missing teeth and the symptom of T. M. disorders were selected for this study : 25 subjects were normal occlusion and 8 subjects were anterior openbite. The ten items were measured from the cephalometric headplates, and EMG recordings of the anterior temporal and masseter muscle were taken at rest position and during maximum clenching at centric occlusion. All data were analyzed and processed with the computer statistical method. The following results were obtained : 1. At rest position, the muscle activities of both temporal and masseter muscle were higher in anterior openbite than in normal occlusion. 2. During maximum clenching, the muscle activities of both temporal and masseter muscle were prominently lower in anterior openbite than in normal occlusion. 3. At rest position, the temporal muscle of anterior openbite showed the highest muscle activity, but showed the lowest muscle activity during maximum clenching. 4. Anterior openbite showed closer interrelationship between facial morphology and the muscle activity, and the muscle activity was more influenced by the form of mandible than that of maxilla.

• Korean Journal of Pharmacognosy
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• v.27 no.2
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• pp.129-135
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• 1996

Euphorbia ebracteolata Hayata is a perennial herb of Euphorbiaceae that has a cyathumal inflorescence, the glands of the involucres are rounded-cordate and reddish, stems are erect, thick and 40-50 cm high. The leaves are alternate and rather numerous. So far this plant has been known as a unreported species in Korea. However, as the result of this study, this plant was found to be widely distributed in Korea over eight habitats, i.e. Keunduk, Dokye and Kaliwangsan, Kangwon-do: Dunduksan, Kyongsangbuk-do: Okcheon, Chungcheongbuk-do: Manduksan, Baekyangsan and Naejangsan, Jeolanam-do. On the other hand, its variety, E. ebracteolata var. coreana Hurusawa which grows only in Poong-do, Kyongki-do was reviewed by comparative morphology and chemotaxonomy to be resulted in the same species, E. ebracteolata.

• Korean Journal of Ichthyology
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• v.10 no.1
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• pp.40-48
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• 1998

Comparative morphology of the genus Branchiostegus has been investigated based on the specimens collected from the adjacent waters of Korea. Branchiostegus japonicus has a distinctive silvery white triangular marking behind eye, while B. albus has nothing. B. albus has about 4 yellow strips along the posterior margin, however, remainder have 5 to 6 longitudinal yellow stripes. In B. auratus, its head length is more than 26% of standard length, but, less than 26% in B. argentatus. This study reveals that B. argentatus is the first record from Korea, and we propose "T$\check{u}$ng-h$\acute{u}$k-ch$\check{o}$m-ok-tu-$\check{o}$" for B. argentatus as a new Korean name.

• ALGAE
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• v.18 no.4
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• pp.239-253
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• 2003

The morphotaxonomic characters of the genus Spirogyra were investigated to clarify their taxonomic category and the variation range among species on the basis of comparative morphological and numerical analyses by unialgal cultures and field samples collected from various freshwater habitats in Korea. 25 characters selected on morphological feature of the species were examined on 568 individuals for morphological comparisons and numerical analyses. Width, length and their length/width ratio of vegetative cell, shape of septum, chloroplast number, maximum width, width, length and their length/width ratio of female gametangium, length of male gametangium, size and shape of zygospore, and cell wall ornamentation of the spore showed a comparatively high vector in principal component analysis. In cluster analysis, 15 taxa analysed were divided into 8 major groups by the average taxonomic distance 1.0 level. Considering the morphology and numerical analysis, Spirogyra crassoidea could not be recognized as an independent species, therefore it was treated as a variety of S. ellipsospora. S. koreana (nom. invalidum), recognized as a new taxon, is under the investigation for its clear taxonomic category.

• 한국신재생에너지학회:학술대회논문집
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• 2009.11a
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• pp.350-354
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• 2009

In this work, polymer - inorganic composites have prepared using polymer such as polyethylene glycol (PEG)/poly (methyl methacrylate, PMMA) and inorganic nanofillers materials such as TiO2 nanotubes (TiNTs)/carbon nanotubes (CNTs). The extensive structural, morphological and ionic properties revealed that the high surface area and tubular feature of nanofillers improved the interaction and cross-linking to polymer matrix which is significantly enhanced the ionic conductivity and electrical properties of composite electrolytes. Comparably high conversion efficiency ~4.5% has been observed by using the newly prepared PEG-TiNTs composite solid electrolyte as compared with PMMA-CNTs electrolyte based DSSCs (~3%). The detailed comparative properties would be discussed in term of their structural, morphology, ionic and photovoltaic properties.

• The Journal of the Korean Society for Microbiology
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• v.21 no.2
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• pp.191-204
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• 1986

Leptospira isolated from the patients with so called epidemic pulmonary hemorrhagic fever were comparatively studied with standard strains obtained from ATCC. The specific aim of this study was to clarify the morphologic heterogeneity of the isolates, i. e., coexistence of spiral forms in both handness, right and left, rod and spherical forms in their population by comparing them with those of the ATCC strains. No differences between our strains and ATCC strains were noticed in their growth characteristics, responses to the culture media, temperature, antibiotics and antifungal agents. Furthermore, the morphologic heterogeneity had been repeatedly observed even in cultures of standard ATCC strains, which had been noticed in the cultures of bacteria isolated in this laboratory. The serologic analysis of our isolates demonstrated that the bacteria reacted with L. icterohaemorrhagiae and L. australis regardless their differences in time of isolation(1984, 1985). Thus, it was concluded that the spiral bacteria isolated in this laboratory are Leptospira of a new serovar which still remained to be determined. And the previous reports on the morphology of the Leptospira, which described that the Leprospira population has only spiral forms with right. handed coils might be reconsidered.