• Applied Microscopy
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• v.29 no.2
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• pp.177-187
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• 1999

Ultrastructure of gametes in the three-spine stickleback, Gasterosteus aculeatus aculeatus was observed, utilizing light, scanning and transmission electron microscopes. The egg of three-spine stickleback is spherical and demersal type. The eggs are highly adhesived to each other but not to substrates. There are many oil droplets in vitelline membrane. The outer surface of egg envelope is arranged by mushroom-like structures and pore canals. The egg have a micropyle, sperm entry site, in the area of the animal pole. The egg envelope consists of three layers, an outer layer with high electron density, a middle layer consisting two layers and an inner layer consisting of 16 to 20 layers. In the fertilized egg envelope, the molecular weights of these components ranged from 14 kDa to 205 kDa. The molecular weights of nam protein bands are 19.4 kDa, 36.7 KDa, 39.4 kDa, 42.9 kDa, 46.1 kDa and 53.0 kDa. The head of spermatozoa is spherical shape and the acrosome is absent. The mitochondria in midpiece are arranged from one to three layers and separated from the axoneme by the cytoplasmic canal. The tail has two lateral fins and the axoneme is of the 9+2 structure.

• Applied Microscopy
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• v.17 no.2
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• pp.1-22
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• 1987

Pemphigus vulgar교의 본태(本態)를 알아보기 위한 일환으로 본질병(本疾病)의 병변조직(病變組織)을 전자현미경적(電子顯微鏡的)으로 관찰(觀察)하고 본질병(本疾病)에 관여(關與)하는 세포(細胞)들에 대(對)해 면역전자현미경적(免疫電子顯微鏡的)으로 추구(追究)하였던 바, 그 결과(結果)를 보고(報告)하는 바이다. 견(犬)의 pemphigus vulgaris의 구강(口腔) 및 식도(食道)의 점막층(粘膜層)을 전자현미경적(電子顯微鏡的)으로 관찰(觀察)하였던 바 acantholysis를 일으켜도 desmosome과 기저막(基底膜)은 큰 변화(變化)가 없었으며 세포간(細胞間)은 세포간물질(細胞間物質)의 집적(集積)에 의(依)해 확장(擴張)되고 이들 세포간강물질(細胞間腔物質)은 집괴(集塊) 또는 무구조(無構造)한 물질(物質)로 나타났다. 그리고 기저세포(基底細胞)는 기저막(基底膜)에 단단히 부착(附着)되어 있었고 dendritic cell이 기저세포층(基底細胞層)위로 분포(分布)되어 있었으며, 이들 dendritic cell 중(中)에서는 가끔 여러 형태(形態)의 퇴행성변화(退行性變化)를 볼 수 있었다. Mouse 피부유리상피세포(皮膚遊離上皮細胞)에 있어서 immunogold-labeling 방법(方法)에 의해 dendritic cell을 동정(同定)하는 데에는 post-fixation, pre-embedding immunogold-labeling technique가 좋았으며 15nm와 40nm 크기의 colloid-fold 입자(粒子)로 Langerhans cell과 Thy-1양성(陽性) dendritic cell이 표식(標識)될 수 있었다. 이들 세포(細胞)들은 세포막항원(細胞膜抗元)에 따라 monoclonal antibody의 반응(反應)에 이어 치밀한 colloid-gold 입자(粒子)가 세포막표면(細胞膜表面)을 따라 일정(一定)하게 표식(標識)되었다. 또한 이들 상피세포(上皮細胞)들을 투과전자현미경적(透過電子顯微鏡的)으로 관찰(觀察)하였을 때 초미세구조(超微細構造)가 잘 보존(保存)되었으나 Langer-hans cell내(內)의 Birbeck granule은 유리전(遊離前) 피부상피조직내(皮膚上皮組織內)의 Langerhans cell내(內)의 Birbeck granule에 비(比)해 수적(數的)으로 현저히 감소(減少)되어 있었다. 그러나 Thy-1 양성(陽性) dendritic cell에서 볼 수 있는 dense-core 과립(顆粒)은 별변화(別變化)없이 쉽게 관찰(觀察)될 수 있었다. 조직배양(組織培養)을 한 견(犬)의 keratinocyte에 대(對)해 사람 pemphigus vulgaris의 항체(抗體)로 반응(反應)시킨 후 protein-A gold(15 nm)로 표식(標識)시킨 바 제일 바깥 상층(上層)의 keratinocyte에 있어서 세포막표면(細胞膜表面)을 따라 표식(標識)되어 세포막항원(細胞膜抗元)을 나타내었으며, 이와 같은 소견(所見)으로 미루어 정상피부(正常皮膚) 중층편평상피세포(重層扁平上皮細胞)에서도 동일(同一)한 소견(所見)을 관찰(觀察)할 수 있다고 본다.

• Applied Microscopy
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• v.35 no.4
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• pp.98-104
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• 2005

A FOV (field-of-view) of the HV-MSC (high voltage multi-scan CCD, $1024{\times}1024$ pixels) camera mounted in the post-column HV-GIF (high voltage gatan image filter) has been drastically enlarged by the projection lens current adjustment. An imaging area of the HV-MSC camera obtained at the lowest magnification (2,000x) is $112{\mu}m^2$ which corresponds to the recording area of the film at the magnification of 8,800x, while the achievable recording area is only $0.43{\mu}m^2$ at the same magnification without this technique. Ignoring the image distortion of less than 5%, we have designed an on-site reference graph to estimate projection lens currents for microscope magnifications above 8,800x, where the recording area on the HVMSC is same as that on the film.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.10 no.1
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• pp.5-12
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• 2000

As a semiconductor material for electronic devices operated under extreme environmental conditions, silicon carbides (SiCs) have been intensively studied because of their excellent electrical, thermal and other physical properties. The growth characteristics of single- crystalline 6H-SiC homoepitaxial layers grown by a thermal chemical vapor deposition (CVD) were investigated. Especially, the successful growth condition of 6H-SiC homoepitaxial layers using a SiC-uncoated graphite susceptor that utilized Mo-plates was obtained. The CVD growth was performed in an RF-induction heated atmospheric pressure chamber and carried out using off-oriented ($3.5^{\circ}$tilt) substrates from the (0001) basal plane in the <110> direction with the Si-face side of the wafer. In order to investigate the crystallinity of grown epilayers, Nomarski optical microscopy, transmittance spectra, Raman spectroscopy, XRD, Photoluninescence (PL) and transmission electron microscopy (TEM) were utilized. The best quality of 6H-SiC homoepitaxial layers was observed in conditions of growth temperature $1500^{\circ}C$ and C/Si flow ratio 2.0 of $C_3H_8$ 0.2 sccm & $SiH_4$ 0.3 sccm.

• Journal of the Microelectronics and Packaging Society
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• v.7 no.2
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• pp.37-42
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• 2000

The comparative study of texture of Al/Ti thin films deposited on low-dielectric polymer and $SiO_2$substrates has been investigated. Fifty-nm-thick Ti films and 500-nm-thick Al-1%Si-0.5%Cu (wt%) films were deposited sequentially onto low-k polymers and $SiO_2$by using a DC magnetron sputtering system. The texture of Al thin film was determined using X-ray diffraction (XRD) theta-2theta ($\theta$-2$\theta$) and rocking curve and the microstructure of Al/Ti films on low-k polymer and $SiO_2$substrates was characterized by cross-sectional transmission electron microscopy (TEM). Both the $\theta$-2$\theta$ method and rocking curve measurement suggest that Al/Ti thin films deposited on $SiO_2$have stronger texture than those deposited on low-k polymer. The texture of Al thin films strongly depended on that of Ti films. Cross-sectional TEM revealed that grains of Ti films on $SiO_2$substrates had grown perpendicular to the substrate, while the grains of Ti alms on SiLK substrates were formed randomly. The lower degree of (111) texture of Al thin films on low-k polymer was due to Ti underlayer.

• The Korean Journal of Zoology
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• v.34 no.2
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• pp.217-227
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• 1991

Ultrastmctura changes of multivesicular bodies and mitochondria of oocytes of PseudopotamU- Ia occelata Moore were examined with transmission electron microscope in order to follow the process of yolk formation. Yolk granules begin to form at the previtellogenic stages of 50 $\mu$m diameter from multivesicular bodies. Small vesicles and membranous structures within the multivesicular bodies are fused to form the precursors of core bodies of yolk granules. Some vesicles from cytoplasm are also coalesced into the multivesicular bodies. Mature yolk granules are composed of electron-dense core bodies which are seperated from each other by electronopaque small vesicle-like structures. Structural changes of cristae into vesicular shapes and increase in electron density of matrix in mitochondria strongly suggested that mitochondria are in the process of transformation. The transformed mitochondria appear to be basic structures which later become multivesicular bodies.

• The Korean Journal of Zoology
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• v.32 no.2
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• pp.107-119
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• 1989

The histochemical characteristics of the cutaneous granular glands and its fine structure of the Korean fire bellied toad, Bombino orientalis Boulenger the only species inhabitated in Korea, were studied with light and electron microscopes. By the granular size and histochemical properties, the granular glands were subdivided into two types. The type I glands have small secretory granules (3.6 $\mu$ m), whereas the type II glands contain relatively larger granules (7.5 $\mu$ m). These two types of glands were simple alveolar gland, and they were commonly composed of inner glandular epithelial cells and outermost myoepithelial cells. By the histochemical reactions, these two secretory granules were not responsed to Alcian blue, but weakly positive reaction was observed in type I granular glands by the PAS reaction. And by the scanning electron microscopic observation, extemal morphology of the opening site of the gland duct was resembled to the stomata of the plant leaves. Especially the epithelial cells of the type I glands had fine reticular surface whereas, type II glands had large vesicular surface. These types of the glands conimonly had larger cavities than those of mucous glands, and forming the multinucleated unicellulr structure (syncytium) at the glandular epithelial layers. Secretory granules of these glands were originated from the rough endoplasmic reticulum of the glandular epithelial cells, and by the maturation level of the granule, morphological diversities appeared.

• Applied Microscopy
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• v.29 no.2
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• pp.149-162
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• 1999

For investigation of the activated carbon on the mouse kidney treated with Pb, the activated carbon (40 mg/kg) and Pb (30 mg/kg) were treated orally for three and six weeks, respectivelly, and observed by the electron microscope. On the glomerulus of the group with only Pb, the basal membrane thicked, projected, and the foot processes fused. On the proximal convoluted tubules, the number of microvilli were decreased and the number of vacuoles and lysosome increased on the cytoplasm. The mitochondria and endoplasmic reticulum were extended and ribosomes dropped from the ER. On the giomerulus of the group with Pb-activated carbon, the basal membrane and the foot processes were merely changed. On the proximal convoluted tubules, the shapes and number of microvilli were not changed and the number of vacuoles, microbodies, and lysosomes decreased. The shapes of mitochondria and endoplasmic reticulum observed almost similar with control group. Th at is, elongated mitochondria and attached ribosomes to endoplasmic reticulum. As result, the activated carbon has positive effect on reducing toxicity of lead in the mouse kidney in the view of electron microscope.

• Korean Chemical Engineering Research
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• v.53 no.6
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• pp.798-801
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• 2015

Nanomaterials (NMs) based on cadmium telluride (CdTe) are the theme of numerous research areas due to their unique chemical and physical properties. NM synthesis via a size-controlled procedure has become an intriguing research topic because NMs exhibit novel optical and physical properties depending on their size and shape. In this study, we prepared CdTe nanowires (NWs) via self-assembly from individual Nanoparticles (NPs). Thioglycolic acid (TGA)-to-Cd ion ratio of 1.3 was used instead of the traditional value of 2.4 and the reduced amount of stabilizer resulted in reorganization from individual NPs into NWs consisting of multi-layers of individual NPs. Transmission electron microscopy (TEM) and scanning electron microscopy (SEM) were performed to characterize NWs. The produced nanowires were straight and long in shape and their length ranged from 500 nm to tens of micrometers.

• Journal of the Korean Society of Food Science and Nutrition
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• v.30 no.5
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• pp.964-968
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• 2001

It was carried out for research and development of natural antimicrobial on Scutellariae Radix extract against food-borne infection bacteria .Scutellariae Radix extract showed remarkable antimicrobial activites against Bacillus cereus, Listeria monocytogenes, Escherichia coli, and Vivro parahaemolyticus when examined by disk method, it was very stable on the wide rane of temperature and pH,.The growth rates of Bacillus cereus, Listeria monocytogenes, Escherichia coli, and Vivro parahaemolyticus were decreased at the concentration of more than 500 ppm Scutellariae Radix extract, Indicating that the minimum inhibitory concentration (MIC)of the Bacillus cereus, Listeria monocytogenes, Escherichia coli, and Vivro parahaemolyticus to Scutellariae Radix extract were around 500 ppm . The morphological changes were observed by transmission electron microscope and scanning electron microscope and the microbial cells membran was destroyed by Scutellariae Radix extract. It was identified that the membrane integrity of the sensitive cells was disrupted by exposure to Scutellariae Radix extract as the $\beta$-galactosidase test on experimental substrate ONPG(o-nitrophenyl-$\beta$-D-galacto-pyranoside)