• Korean Journal of Head & Neck Oncology
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• v.2 no.1
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• pp.67-73
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• 1986

An unusual polypoid laryngeal tumor has been studied with light and electron microscopy. In light microscopic section, there were two components: a squamous cell carcinoma and a sarcomatoid spindle cell population. Transitional zone between these two components was found. The electron micrographs demonstrated the presence of slender bundles of tonofilaments in many tumor cells. Desmosomes were present, but few in number and poorly developed. Findings suggest this laryngeal tumor as a spindle cell variant of squamous cell carcinoma.

• Bulletin of the Korean Chemical Society
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• v.6 no.5
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• pp.304-308
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• 1985

Morphological structure of tin oxide thin films was examined by transmission electron microscopy. TEM samples were prepared by chemical etching in hydrogen fluoride solution: firstly floating for 2-3 minutes in acid solution, then suspending on water found to be useful for the preparation of TEM samples. Electron micrographs showed the size of grains of the tin oxide crystal was dependent upon the temperature of the film preparation. Dopant concentration and heating time also influence the grain size. The resistivity of tin oxide material was explained by grain size and grain boundaries in a limited temperature and dopant concentration ranges.

• Animal cells and systems
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• v.7 no.1
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• pp.35-41
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• 2003

The principal fibers used in constructing the cocoon in the garden spider, Argiope aurantia, are large-diameter fibers developed from tubuliform glands and small-diameter fibers presumed to be spun by the aciniform silk glands. Scanning electron micrographs of the large-diameter fibers on both surfaces of the cocoon clearly reveal their fine structural differences. While the silk fibers on the inner surface have smooth and homogeneous appearances, each fiber on the outer surface represents a multicomponent internal structure. Examination of each fibers using transmission electron microscope also provides additional evidence that the multicomponent fibers contain numerous electron lucent fibrils embedded in an amorphous electron dense matrix. It has been also revealed that two types of secretory granules presumed to be the precursors of tubuliform fibers are closely related to the production of distinct coloration in luminal contents - brownish and yellowish components. Moreover, these electron-dense granules, possibly precursor of fibrillar component, and electron-lucent granules, possibly precursor of matrix component, are densely packed and remain close to each other without fusion. It is critical evidence that the individual tubuliform fiber is not only heterogeneous and multicomponent but also takes place in a variety at manners throughout the length of the gland.

• Mycobiology
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• v.28 no.1
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• pp.47-50
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• 2000

The capability of higher ascomyceteous fungi to cause typical soft-rot decay for wood under laboratory conditions is reviewed and discussed. Fungi tested were extremely active in the decomposition of timbers. Scanning electron micrographs illustrated typical soft-rot decay pattern of higher wood decay ascomycetes, with the exception of H. trugodes that caused white-rot decay. Most of the fungi tested could be grouped as soft-rot fungi that showed typical soft-rot type II. Hypha confined primarily to the resin canals in softwoods or vessel elements in hardwoods and spread tracheid to tracheid via pits of cell wall to cell wall with mechanical force.

• Applied Microscopy
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• v.31 no.1
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• pp.1-8
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• 2001

The morphological features of neuronal dendritic spines are changed their shapes, sizes and density in response to physiological or pathological conditions . Therefore, exact analysis of spines warrants understanding of neuronal function. The size of the spine is at the borderline of resolution with light microscopy. High voltage electron microscopy Provide excellent resolution of the spines with proper stain techniques thanks to its higher resolution and penetration power. We evaluated more effective staining method for observing dendritic spines after labeling Purkinje cells with anti-calbindin 28 kD immunohistochemistry or Golgi staining methods. 4 fm thickness sections were observed with high voltage electron microscopy and some morphometric analyses were performed. Both Golgi staining and immunohistochemistry revealed the detail structures of the Purkinje cell such as soma, dendrites, and dendritic spines. High voltage electron micrographs with Golgi staining provide more precise morphology and are easy to measure. Average density of spine is $24.5{\pm}3.6/10{\mu}m$ and its length is $1.12{\pm}0.22{\mu}m$. For quantitative analysis of the spines, high voltage electron, micrographs with Golgi staining are more effective. This preliminary result is expected to be useful for further study of spine plasticity in various conditions.

• Geomechanics and Engineering
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• v.21 no.5
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• pp.413-422
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• 2020

The choice of eco-friendly materials for ground improvement is a necessary way forward for sustainable development. Adapting naturally available biopolymers will render the process of soil stabilization carbon neutral. An attempt has been made to use β-glucan, a natural biopolymer for the stabilization of lean clay as a sustainable alternative with specific emphasis on comprehending the effect of confining stresses on lean clay through triaxial compression tests. A sequence of laboratory experiments was performed to examine the various physical and mechanical characteristics of β-glucan treated soil (BGTS). Micro-analysis through micrographs were used to understand the strengthening mechanism. Results of the study show that the deviatoric stress of 2% BGTS is 12 times higher than untreated soil (UTS). The micrographs from Scanning Electron Microscopy (SEM) and the results of the Nitrogen-based Brunauer Emmett Teller (N₂-BET) analysis confirm the formation of new cementitious fibres and hydrogels within the soil matrix that tends to weld soil particles and reduce the pore spaces leading to an increase in strength. Hydraulic conductivity (HC) and compressibility reduced significantly with the biopolymer content and curing period. Results emphases that β-glucan is an efficient and sustainable alternative to the traditional stabilizers like cement, lime or bitumen.

• Journal of the Korean Society for Precision Engineering
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• v.16 no.8
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• pp.9-15
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• 1999

Die-sinking electrical discharge machining(EDM) for conductive ceramic matrix composite(CMC) of Tic/$Al_2O_3$ was experienced with addition of ultrasonic emission, and the results were compared with ones obtained by the EDM only. From this experimental study, the values of material removal rate(MRR) and surface roughness($R_{max}$), scanning electron microscope(SEM) micrographs, and weibull probability distribution of bending strength for the specimens were obtained and compared. The trend of MRR was found to be increased slightly with the current and the duty factor for both EDM only and EDM with ultrasonic emission. The MRR values were found to be increased for EDM with ultrasonic emission. The SEM micrographs of EDMed surface by under various operating conditions showed less micro cracks in various places. Although smaller bending strength value was obtained by EDMed surface with ultrasonic emission by weibull probability distribution analysis of bending strength.

• Korean journal of food and cookery science
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• v.21 no.4 s.88
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• pp.528-535
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• 2005

This paper aims to compare and evaluate the quality of beef jerky made with Korean beef meat, Korean beef cattle and imported beef meat from Australia and New Zealand through sensory evaluation, measurement of hardness, thickness and contents of the moisture and crude lipid, and microscopic texture observation (SEM). According to the sensory evaluation, beef jerky made with Korean beef meat recorded the highest score in overall acceptability; New Zealand beef meat, the lowest. The preference of beef jerky made with Korean beef meat was shown in the appearance, smell, and texture, and especially in the taste. Whereas Korean beef jerky scored highest in color, glaze and palatability, New Zealand beef meat showed the lowest score. Korean beef meat showed the lowest in hardness, but New Zealand beef meat showed the highest as shown in the result of technical evaluation through rheometer. The evaluation through colormeter concluded that New Zealand beef meat had the highest scores in L and a values, but that Korean beef meat showed the lowest score. When it comes to the color difference compared with Korean beef meat, New Zealand beef meat showed the biggest difference. Although the moisture contents of jerky made with different beef meat showed little difference, the content of the crude lipid of jerky made with Korean beef meat and Australian beef meat was lower than that of Korean beef cattle and New Zealand beef meat. When the beef jerky is dry, fat contained in the beef meat is dissolved, which causes the glaze on the outside. Scanning electron micrographs showed that Korean and Australian beef jerky had larger gaps than Korean beef cattle and New Zealand beef jerky. It was concluded that this affected the hardness of beef jerky.

• Applied Microscopy
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• v.28 no.4
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• pp.539-549
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• 1998

The silk glands of the spiders are of several types. Among the several types of spider's silk glands, the principal fibers used in constructing the eggcase are products of the tubuliform glands (TBG), which are present only in females. Development of these glands parallels maturations of the ovaries and fat bodies. In order to understand the mechanism of eggcase-silk production, this paper has examined the fine structural changes of the TBG during the period of egg maturation in the garden spider, Argiope aurentia. Between the two kinds of secretory granules observed in the glandular epithelium of the mature TBG, the electron-dense granules which have paracrystalline structure are revealed to be the precursors of the eggcase silk fibers. During the production of eggcase, rapid release of the secretory product occurs at apical surface by the mechanism of apocrine secretion. Moreover, secondary lysosomes appear due to the rapid disorganization of cellular components during the eggcase formation. Examinations of formed fibers indicate a multicomponent internal structure, and electron micrographs reveal each fiber contains numerous electron lucent fibrils embedded in an amorphous electron dense matrix. The secretory precursors are produced as separated vesicles via well-oriented rER, and no Golgi complex has been found in the glandular epithelial cells.

• The Plant Pathology Journal
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• v.22 no.3
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• pp.230-234
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• 2006

Tomato spotted wilt virus (TSWV) has been identified in commercial chrysanthemum cultivars in Korea. Nucleotide sequences of the N gene of TSWV-ch14 isolated from infected chrysanthemum were determined and deposited in GenBank under accession no. DQ453158. The symptoms consisted of dark colored leaf necrosis, black streaks along the stem, wilting of plant parts in 'Sinma'; and chlorotic spots, necrosis of axillary shoots and withering of leaves in 'Hwarang'. Electron micrographs of leaf preparation of Nicotiana rustica infected with TSWV-ch14 contained spherical particles around 85 nm in diameter. TSWV was identified from chrysanthemum by sequence determination of N nucleocapsid protein and virion observation by transmission electron microscope. This is the first reported observation on TSWV in chrysanthemum in Korea.