• Applied Microscopy
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• 제12권1호
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• pp.49-56
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• 1982

전신성 Cryptococcosis로 판명된 4세 남아의 피부 생검조직에서 발견된C. neoformans의 미세구조를 광학현미경 관찰과 함께 보고 하였다. 광학현미경 관찰에서는 각종 만성 염증 세포의 침윤과 함께 다수의 구형의 organism을 관찰할 수 있었다. 전자현미경적으로도 난원형의 세포가 gelatinous 또는 filamentous한 capsular material에 둘러 싸여 단세포 혹은 여러개의 세포가 모여 있는 상태로 관찰되었으며 budding중인 상태의 것도 관찰되었다. 세포막은 고전사 밀도의 여러층으로 구성되어 있었으며 한개의 핵과 핵인이 관찰되었고 세포질내에는 mitochondria, ribosome, lipid bodies, vacuole등과 함께 plasma membrane의 infolding으로 형성된 mesosome-like structure도 관찰되었다.

• 한국주조공학회지
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• 제28권2호
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• pp.79-84
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• 2008

Metal foam is one of the most interesting materials with various multi-functional properties such as light weight, energy absorption, high stiffness and damping capability. Among them, energy absorption property has keen interests in the field of automotives for passenger protection. Nowadays, researches about pore size and porosity control of the foam are increased to correspond them. However, though energy absorption properties are improved, these results are not cost-effective process. In present research, however, as a part of improving the energy absorption property of metallic foams, 606X aluminum alloy was used for cell wall material which has higher strength than pure aluminum. And its morphological features are characterized. As a results, porosity and pore size are uniformity distribution with increasing foaming temperature in the case of 6061 alloy foams. 6063 alloy foam specimens have opposite tendency because of the influence of alloying element and viscosity of the molten melt.

• Journal of Microbiology and Biotechnology
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• 제12권2호
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• pp.235-241
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• 2002

Sophorolipid, a biosurfactant produced from Candida bombicola ATCC 22214, showed antimicrobial activity against Bacillus subtilis, Staphylococcus xylosus, Streptococcus mutans, and Propionibacterium acne at 4, 1, 1, 0.5 ppm, respectively. Also, 100 ppm of sophorolipid inhibited $50\%$ of cell growth of plant pathogenic fungus, Botrytis cineria. However, sophorolipid showed no effect on Escherichia coli, indicating that its selective antimicrobial activity depended on the cell wall structure. Treatment of B. subtilis with sophorolipid increased leakage of intracellular enzyme, malate dehydrogenase, indicating a possible interaction of sophorolipid with a cellular membrane. Comparing lactone-type and acid-type sophorolipids, the former showed a higher antimicrobial activity. Supplementing other surfactants showed no significant effects on the antimicrobial activity. Animal study showed that 5 g of sophorolipid per kg body weight by oral administration caused no toxicity, and sophorolipid induced no irritation on the skin. These results show potential use of sophorolipid as an active ingredient in healthcare products.

• 한국환경보건학회지
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• 제21권3호
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• pp.23-27
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• 1995

To extend the shelf lives of rice and corn products, the effects of the polyphosphates[$Na(PO_3)n$, n=11] on the growth of Penicillium griseofulvum and patulin production were investigated. The growth was completely inhibited in the potatoes dextrose agar medium treated with 2% polyphosphate. Moisture content had a considerable influence on the production of patulin. At 30% moisture content, the amounts of patulin produced in rice and corn were $61.40 \mu g/ml$ and $40.74 \mu g/ml$, respectively, but the level of the toxin was significantly decreased to 93~95% by addition of 1% polyphosphates. No patulin was detected in both rice and corn medium added 2% polyphosphate when the incubation time prolonged. The result of scanning electron microscopy was supposed that the biocidal action of polyphosphate on fungi was related to the collapse of cell wall structure.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2011년도 춘계학술대회 논문집
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• pp.1774-1785
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• 2011

In this paper, Rigid Reinforced Roadbed(RRR) which is expected to have highly applicability to railroad roadbed, was introduced and field tests results were analyzed. Full scale model with 5m height concerning a single track railroad roadbed was constructed. The model had four different sections, which was to assess the effect of geogrid length, spacing, and connection method on deformation characteristics of RRR. Laser displacement meter, earth pressure cell, piezometer, and strain gauge were installed in order to analyze the behavior of reinforced embankment during construction. Horizontal displacements caused by compaction at each section were 20~30% below the displacement limit that of general reinforced retaining wall, which showed that RRR was very stable structure. Maximum tensile strength of reinforcement was withing 10% of the long-term design strength.

• Journal of Microbiology and Biotechnology
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• 제11권2호
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• pp.281-286
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• 2001

Since the number of amino groups which are exposed by deacetylation of acetyl-D-glucosamine influences antimicrobial activity, a chitosan oligosaccharide (COS) derivative by N-conjugation of COS with asparagine, an amino acid with two amino groups, was synthesized and the antimicrobial effect on E. coli growth was compared with other COS derivatives which were N-conjugated with glycine, alanine, aspartic acid, cysteins, an methionine, and unmodified COS. The structure of asparagine N-conjugated COS (Asn-COS) derivative was identified by using a FT-IR, $^{13}C\;FT-NMR$, and an elemental analyzer. The antimicrobial activity of Asn-COS against E. coli growth was significantly improved as compared to the other COS derivatives as well as COS itself. This means that Asn-COS with two positive charges strongly interacts with the carboxyl negative charges on the bacteria cell wall. The results for Asn-COS were as follows: 100% bactericidal activity, 0.002% MIC, and no growth of E. coli during 3 days of culture time, suggesting that Asn-COS may be useful as a new antibiotic agent.

• Journal of Plant Biology
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• 제34권3호
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• pp.201-213
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• 1991

This study has been carried out to investigate the ultrastructural changes, formation of storage materials in endosperm cells with electron microscope during the seed formation of Panax ginseng C.A. Meyer. In the early stage of seed formation with green seed coat, the endosperm was cellular type. Cell plate was largely composed of dictyosome vesicles in early stage of wall formation after mitosis. Central vacuole was gradually subdivided into several small-sized vacuoles. During the differentiation of plastids, some proplastid was replaced by amyloplast with starch grains and lamellar structure. A number of mitochondria with well developed cristae were distributed in cytoplasm. Rough endoplasmc reticulum, dictyosome, microbody, free ribosomes and polysomes were evenly distributed in cytoplasm. Spherical spherosomes were formed from dictyosome containing the lipid materials of even electron density. Protein bodies were formed by interfusing between vacuoles and vesicles derived from rough endoplasmic reticulum which contained the amorphous protein of high electron density.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2000년도 영호남학술대회 논문집
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• pp.120-123
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• 2000

Bridge Type Cell structure informed that the efficiency is increased by about 30% compared to the conventional type has been investigated during addressing period. As a result, the addressing time is decreased by about 20% compared to the conventional type. And wall charge distribution was analyzed Quantitatively in three electrodes during addressing period.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2004년도 춘계학술대회 논문집 디스플레이 광소자분야
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• pp.146-149
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• 2004

We have studied a liquid crystal (LC) mode (named locked super homeotropic (LSH)) in which the LCs aligned homeotropically are locked by surrounding walls such as cubic, hexagonal and cylinder. In the device, the vertically aligned LCs tilt down symmetrically around the center of the cell when a voltage is applied and thus it exhibits wide viewing angle. The structure of this LSH mode is suitable for large-sized display panels. since the LCs are locked in micro domains the LCs do not flow to the bottom of the panel by gravity. This mode is applicable to achieve high performance TFT-LCD TV because of high performance characteristics such as high contrast, high brightness, wide-viewing angle.

• Tuberculosis and Respiratory Diseases
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• 제74권3호
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• pp.97-103
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• 2013

A lung cyst is an air-filled lucent structure surrounded by a thin wall. The presence of multiple intrapulmonary cysts is defined as cystic lung disease. Although cystic lung disease is rare, incidental detection has increased significantly in recent years by screening using computed tomography. There are many conditions that can mimic lung cysts and cause cystic lung disease. Clinical, radiographic, and histologic findings are all necessary for a proper diagnosis, and multidisciplinary approaches are frequently required. The aim of this report is to review the causes and characteristics of cystic lung disease to better understand and improve treatment.