• Korean Journal of Plant Taxonomy
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• v.33 no.3
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• pp.255-270
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• 2003

Pollen morphology of four genera (Daphne L. - 4 spp., Edgeworthia Meisn. - 1 sp., Wikstroemia Endl. - 2 spp., and Stellera L. 1 sp.), except 1 taxon (Diarthron Turcz. - 1 sp.) in Korean Thymelaeaceae were examined with light (LM) and scanning electron microscopy (SEM). The size of grains ($11.3-60.0{\mu}m$) are varied from small (in Stellera) through medium (in Daphne and Wikstroemia) to large (in Edgeworthia). All studied taxa have monad, spheroidal, pantoporate (10-20) grains. The exine is reticulate, especially a typical "croton pattern" which is comprising rings of more or less trihedral subunits. Each triangular subunit is topped by a single microspinule, and the surface pattern is psilale. In Daphne, three types of subunit arrangement can be recognized; - (1) Type I : subunits are arranged circles and attached to each other or sometimes fused in part, (2) Type II: each subunit is trihedral and isolated distinctly, and (3) Type III: each subunit is isolated, but somewhat vague. Systematic implication of the present pollen data for the Korean Thymelaeaceae is also briefly discussed.

• Korean Journal of Plant Taxonomy
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• v.38 no.4
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• pp.389-403
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• 2008

Seed morphological studies of 12 species of sect. Zygophyllidium and related Poinsettia using light and scanning electron microscopy were conducted to test the hypotheses of the sectional boundaries and species relationships. Characteristics of seeds, and the keys of identification of 12 species were presented. Seeds of 12 species were divided into 6 types based on the UPGMA tree from numerical analyses using nine seed characters. Type I, including E. uniglandulosa, is characterized by the foveolate seed with granulate testa cells. Type II, including species E. exstipulata, E. lagunensis, E. bilobata, E. hexagonoides and E. chersonesa, was recognized by the presence of inter-cellular granules among testa cells. Type III, including E. cyathophora, has a seed with acute apex, and concentric circles on the surface of testa cells. Type IV, including species of E. dentata and E. pentadactyla, has a seed with caruncle and lacking inter-cellular granules among testa cells. Type V, including E. hexagona, was characterized by the ovate seeds and lacking inter-cellular granules. Type VI, including E. eriantha and E. lacera, was recognized by the seeds with rectangular shape with caruncle. Based on the seed morphology, sect. Zygophyllidium should be defined only species with E. exstipulata, E. lagunensis, E. bilobata, E. hexagonoides and E. chersonesa. E. hexagona, traditionally included in this section, was closely related to E. dentata from Poinsettia.

• Korean Journal of Plant Taxonomy
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• v.40 no.1
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• pp.50-58
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• 2010

The nutlet morphology and pericarp structure of 14 taxa (4 taxa of the genus Glechoma and related taxa) were studied by light and scanning electron microscopy, and a detailed description of nutlet morphological features for all examined taxa is provided. The shape of the nutlet is ovate to elliptic. Its size is 1.36-3.83 mm in length and 0.80-2.65 mm in width. The largest one was found in Marmoritis rotundifolia, while the smallest one was in Agastache nepetoides. Three different surface types were recognized in the studied taxa based on differences in cell outline and cell boundary relief (rectangular, pitted, and ridged negative reticulate-cell). Three types of trichome (uni-cellular non-glandular trichome, multi-cellular non-glandular trichome, and peltate glandular trichome) were distributed in the nutlets. The pericarp is formed in three layers (i.e., exocarp, mesocarp, and endocarp including sclenchyma tissue), and the pericarp in the studied species is $39.0-237.5{\mu}m$ thick. The morphological and anatomical features (the nutlet shape, surface type, and trichome distribution) in the genus Glechoma and related taxa are described and discussed.

• The Korean Journal of Malacology
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• v.28 no.1
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• pp.65-71
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• 2012

Protozoan parasites belonging to the genus Perkinsus elicit severe inflammatory responses and are associated with mass mortality of commercially important marine shellfish worldwide. In the present study, we examined the external features of P. olseni zoospores in detail using light and scanning electron microscopy. Our study showed that the zoospores have an oval body with a long anterior flagellum and a short posterior flagellum. The anterior flagellum has a unilateral array of mastigonemes. Mean body dimensions were $3.37{\pm}0.33{\mu}m{\times}1.72{\pm}0.22{\mu}m$. The average length of the anterior and posterior flagella was $16.34{\pm}1.52{\mu}m$ and $8.25{\pm}1.39{\mu}m$, respectively. Zoospores of P. olseni found in Korean waters have shorter and narrower bodies, longer anterior flagella, and shorter posterior flagella than zoospores of Perkinsus spp. found in the mollusks of North America and Europe.

• Journal of Adhesion and Interface
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• v.19 no.3
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• pp.106-112
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• 2018

Recently, the hyperthermia treatment of malignant tissues has gained great attention as a biocompatible and benign method that facilitates successful cancer therapy compared to radiation and chemotherapy. In this study, superparamagnetic ($Fe_3O_4$) iron oxide nanoparticles (IONP) coated with biocompatible polymer (IONP@P(MPC/FOM)) for the purpose of hyperthermia treatment were prepared and related characterization were performed. IONPs with having 15 nm diameter were first prepared by coprecipitation and followed by surface modification with 4-cyanopentanoic acid dithiobenzoate (CTP) for reversible addition-fragmentation chain transfer (RAFT) copolymerization by using 2-methacryloyloxyethyl phosphorylcholine (MPC) and fluorescein O-methacrylate (FOM) to form corona layer of P(MPC/FOM) on the surface of the IONP. Transmission electron microscopy (TEM) and dynamic light scattering (DLS) confirmed the morphology and hydrodynamic size of the IONP@P(MPC/FOM) and thermogravimetric analysis (TGA) confirmed the formation of P(MPC/FOM) corona layer, respectively. Exposing IONP dispersion to alternating magnetic field suggests that the IONP@P(MPC/FOM) aqueous dispersion with 0.2 wt.% can be used for hyperthermia treatment.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.36 no.2
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• pp.105-113
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• 2010

This study introduces a flexible approach to enhance skin permeation by using ethosomes with deformable lipid membranes as well as controllable sizes. To demonstrate this, a set of ethosomes encapsulating an anti-hair loss ingredient, Triaminodil$^{TM}$, as a model drug, were fabricated with varying their size, which was achieved by solely applying the different level of mechanical energy, while maintaining their chemical composition. After characterization of the ethosomes with dynamic light scattering, transmission electron microscopy, and deformability measurements, it was found that their membrane deformability depended on the particle size. Moreover, studies on in vitro skin permeation and murine anagen induction allowed us to figure out that the membrane deformability of ethosomes essentially affects delivery efficiency of Triaminodil$^{TM}$ through the skin. It was noticeable in our study that there existed an optimum particle size that can not only maximize the delivery of the drug through the skin, but also increase its actual dermatological activity. These findings offer a useful basis for understanding how ethosomes should be designed to improve delivery efficiency of encapsulated drugs therein in the aspects of changing their length scales and membrane properties.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.33 no.3
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• pp.214-218
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• 2020

In this study, Mg_xZn_1-xO thin films, which can be applied not only to active layers of light-emitting devices (LEDs), such as UV-LEDs, but also to solar cells, high mobility field-effect transistors, and power semiconductor devices, are fabricated using the sol-gel method. ZnO and Mg_0.3Zn_0.7O solution synthesized by the sol-gel method and the thin film were grown by spin coating on a Si (100) substrate and sapphire substrate. The solutions are synthesized by dissolving precursor materials in 2-methoxyethanol (2-ME) solvent, and then monoethanolamine (MEA) was added to the mixed solution as a sol stabilizer. Zinc acetate dihydrate is used as a ZnO precursor, while Mg nitrate hexahydrate and Mg acetate tetrahydrate are used as an MgO precursor. Then, the optical and structural characteristics of the fabricated thin films are compared. The molar concentration of the Zn precursor in the solvent is fixed at 0.3 M, and the amount of the Mg precursor is 30% of Mg²⁺/Zn²⁺. The optical characteristics are measured using an UV-vis spectrophotometer, and the transmittance of each wavelength is measured. Structural characteristics are measured using X-ray diffraction (XRD) and transmission electron microscopy (TEM). Composition analyses are performed using energy dispersive X-ray spectroscopy (EDS). The Mg_0.3Zn_0.7O thin film was well formed at the ratio of the Mg precursor added regardless of the type of Mg precursor, and the c-axis of the thin film was decreased, while the band gap was increased to 3.56 eV.

• Korean Journal of Materials Research
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• v.22 no.7
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• pp.379-383
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• 2012

$TiO_2$ thin films consisting of positively charged poly(diallyldimethylammonium chloride)(PDDA) and negatively charged titanium(IV) bis(ammonium lactato) dihydroxide(TALH) were successfully fabricated on glass beads by a layer-by-layer(LBL) self-assembly method. The glass beads used here showed a positive charge in an acid range and negative charge in an alkaline range. The glass beads coated with the coating sequence of(PDDA/TALH)n showed a change in the surface morphology as a function of the number of bilayers. When the number of bilayers(n) of the(PDDA/TALH) thin film was 20, Ti element was observed on the surface of the coated glass beads. The thin films coated onto the glass beads had a main peak of the (101) crystal face and were highly crystallized with XRD diffraction peaks of anatase-type $TiO_2$ according to an XRD analysis. In addition, the $TiO_2$ thin films showed photocatalytic properties such that they could decompose a methyl orange solution under illumination with UV light. As the number of bilayers of the(PDDA/TALH) thin film increased, the photocatalytic property of the $TiO_2$-coated glass beads increased with the increase in the thin film thickness. The surface morphologies and optical properties of glass beads coated with $TiO_2$ thin films with different coating numbers were measured by field emission scanning electron microscopy(FE-SEM), X-ray diffraction(XRD) and by UV-Vis spectrophotometry(UV-vis).

• Parasites, Hosts and Diseases
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• v.53 no.5
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• pp.619-625
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• 2015

The present study was performed to determine the infection status of swamp eels with Gnathostoma sp. larvae in Myanmar. We purchased total 37 Asian swamp eels, Monopterus albus, from a local market in Yangon in June and December 2013 and 2014. All collected eels were transferred with ice to our laboratory and each of them was examined by the artificial digestion technique. A total of 401 larval gnathostomes (1-96 larvae/eel) were detected in 33 (89.2%) swamp eels. Most of the larvae (n=383; 95.5%) were found in the muscle. The remaining 18 larvae were detected in the viscera. The advanced third-stage larvae ($AdL_3$) were 2.3-4.4 mm long and 0.25-0.425 mm wide. The characteristic head bulb ($0.093{\times}0.221mm$ in average size) with 4 rows of hooklets, muscular long esophagus (1.025 mm), and 2 pairs of cervical sacs (0.574 mm) were observed by light microscopy. The average number of hooklets in the 1st, 2nd, 3rd, and 4th rows was 41, 45, 48, and 51, respectively. As scanning electron microscopic findings, the characteristic 4-5 rows of hooklets on the head bulb, a cervical papilla, tegumental spines regularly arranged in the transverse striations, and an anus were well observed. Based on these morphological characters, they were identified as the AdL3 of Gnathostoma spinigerum. By the present study, it has been confirmed for the first time that Asian swamp eels, M. albus, from Yangon, Myanmar are heavily infected with G. spinigerum larvae.

• Journal of the Korean Society of Physical Medicine
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• v.9 no.2
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• pp.133-140
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• 2014

PURPOSE: The purpose of this study was to compare the effect of current density on penetration depth, tissue concentration and transdermal transport of methylene blue(MB) by iontophoretic transdermal delivery. METHODS: Twenty-four male Sprague-Dawley rats were randomly divided into 1 mA($0.11mA/cm^2$), 2 mA($0.22mA/cm^2$), 4 mA($0.44mA/cm^2$), and 8 mA($0.89mA/cm^2$) groups. These rats were exposed to anodic iontophoresis of 1% MB using a direct current for 15 minutes. The penetration depth were measured using light microscopy from cryosections of skin tissue. The tissue concentration and transdermal transport were measured using biochemical analysis from target skin tissues. The data were analyzed with one-way analysis of variance. RESULTS: The significant differences in the penetration depth, tissue concentration and transdermal transport were detected among the groups(p<.001). Post hoc comparisons of the penetration depth, tissue concentration and transdermal transport of he 2 mA, 4 mA, and 8 mA iontophoresis groups were greater than in the 1 mA iontophoresis group(p<.05). There was no significant difference, however, among 2 mA, 4 mA, and 8 mA iontophoresis group. CONCLUSION: There was no difference in the efficiency of iontophoresis from 2 mA($0.22mA/cm^2$) to 8 mA($0.89mA/cm^2$). Higher current density can cause skin injury and discomfort sensation. In general, $0.5mA/cm^2$ is proposed to be the maximum iontophoretic current which should be used on human. The appropriate current amplitude should be selected by considering the safety current density and the depth of the target tissue.