• 한국전자현미경학회:학술대회논문집
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• 한국현미경학회 2005년도 제36차 추계학술대회 및 제4회 HVEM 이용자 워크샵
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• pp.127-129
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• 2005

Bacterial lipopolysaccharide(LPS) is can stimulate the most LPS-responsive cells in the mammalian host. The macrophage response to LPS can protect the host from infection but high levels, contribute to systemic inflammatory response syndrome and destruction of host itself, The previously study, secretory leukocyte pretense inhibitor (SLPI) was known LPS-induced product of macrophage and had the function that antagonizes their LPS-induced activation of pro-inflammation signaling factors. Purpose of this study was to identify the expression of SLPI involving the infection in various cell lines including odontoblast cell line. Therefore, we conducted in vitro researches, which treated the LPS to the MDPC-23, and compared to NIH3T3, RAW264.7. To investigate the expressionof SLPI in mRNA level, the methods was used RT-PCR and western blotting for protein expression of SLPI. Moreover, we performed the scanning electron microscopic (SEM) observation for the morphological change. This work was supported by Korea Science and Engineering Foundation.

• 한국수산과학회지
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• 제34권1호
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• pp.38-42
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• 2001

Metapenaeopsis dalei의 탈피과정 및 기작을 구명하기 위하여 1999년 3월부터 5월 사이에 통영 용초도 주변 해역에서 채집된 자 각장 $13{\pm}2mm$의 개체를 사용하였다. 강모의 발달과 탈피단계는 미지 부분을 절개, 현미경으로 관찰하여 그 미세구조를 바탕으로 판정하였다. M. dalei의 주 탈피단계는 5개 (Stage A, B, C, D와E)로 나눌 수 있었다. Stage B에서는 setal cone의 생성을 확인할 수 있었으며, Stage $D_1'$에서는 setal shafts을 관찰할 수 있었다. 탈피단계 (Stage E)는 매우 빠르게 진행되어, 1분을 초과하지 않았다.

• The Plant Pathology Journal
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• 제20권3호
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• pp.177-183
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• 2004

Phenylacetic acid (PAA) was evaluated for in vitro anti-oomycete activity and in vivo control efficacy against Phytophthora capsici. Microscopic observation revealed that the high level of anti-oomycete activity of PAA (10 $\mu\textrm{g}$/ml) against P. capsici is mainly due to the lytic effect on zoospores. Zoospore lysis began in the presence of 5 u$\mu\textrm{g}$/ml of PAA and most of the zoospores were collapsed at 10 $\mu\textrm{g}$/ml. PAA showed inhibitory activity against the zoospore germination and hyphal growth of P. capsici at the concentration of 50 $\mu\textrm{g}$/ml. In the glasshouse, the protective effect of PAA against Phytophthora blight was high on pepper plants when treated just before inoculation with P. capsici. In the artificially infested field, protection of pepper plants against the Phyto-phthora epidemic was achieved at a considerable level by PAA treatment.

• Mycobiology
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• 제42권1호
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• pp.22-26
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• 2014

The diversity of the genus Megacollybia in Korea was examined based on morphological observation and analysis of molecular data. Currently, the genus is consisted of nine species with a global distribution. However, only M. platyphylla has been reported in the floral survey of Korea. During our re-evaluation of the taxonomic diversity of Megacollybia in Korea, six Megacollybia specimens collected in 2012 were identified based on internal transcribed spacer (ITS) sequences and morphology. Here, we report two Megacollybia species, M. clitocyboidea and M. marginata, as newly recorded species from Korea. The microscopic features of the two species are provided in this study. To our knowledge, this is the first phylogenetic analysis of Korean Megacollybia species.

• Advances in concrete construction
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• 제3권4호
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• pp.283-293
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• 2015

This paper presents the effects of elevated temperatures of $400^{\circ}C$ and $800^{\circ}C$ on the residual compressive strength and failure behaviour of fibre reinforced concretes and comparison is made with that of unreinforced control concrete. Two types of short fibres are used in this study e.g., steel and basalt fibres. The results show that the residual compressive strength capacity of steel fibre reinforced concrete is higher than unreinforced concrete at both elevated temperatures. The basalt fibre reinforced concrete, on the other hand, showed lower strength retention capacity than the control unreinforced concrete. However, the use of hybrid steel-basalt fibre reinforcement recovered the deficiency of basalt fibre reinforced concrete, but still slightly lower than the control and steel fibres reinforced concretes. The use of fibres reduces the spalling and explosive failure of steel, basalt and hybrid steel-basalt fibres reinforced concretes oppose to spalling in deeper regions of ordinary control concrete after exposure to above elevated temperatures. Microscopic observation of steel and basalt fibres surfaces after exposure to above elevated temperatures shows peeling of thin layer from steel surface at $800^{\circ}C$, whereas in the case of basalt fibre formation of Plagioclase mineral crystals on the surface are observed at elevated temperatures.

• Applied Microscopy
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• 제18권2호
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• pp.205-217
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• 1988

An ultrastructural study of hepatocyte proliferation in the regenerating rat liver has been made by means of the partial hepatectomy. And electron microscopic histochemistry of hepatocyte in the regenerating rat liver is studied through alkaline phosphatase reaction. The results are as follows: 1. When the regeneration of rat liver is induced by the partial hepatectomy, the prominent ultrastructural characteristics of hepatocyte are changes of the distribution of chromatin in nucleus, increase of the number of mitochondria and decrease of the size of them, development of rough endoplasmic reticulum, and transient decrease of glycogen granules in cytoplasm. 2. Alkaline phosphatase reaction products are appeared in the nucleus or rough endoplasmic reticulum of hepatocyte during the initial regeneration of liver as 24, 48 and 72 hour groups after partial hepatectomy. And these positive reaction are mainly increased in cytoplasm and plasma membrane of hepatocytes during 1, 2 and 3 week groups after partial hepatectomy. As 4 weeks passed after partial hepatectomy, these positive reaction is located in the sinusoidal epithelial cells or erythrocytes. With above results, we concluded that alkaline phosphatase was synthesized in the rough endoplasmic reticulum bounded ribosomes of regenerating hepatocyte, was transported to the plasma membrane of them, and then was transported in blood by the way sinusoidel epithelial cells.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1991년도 추계학술대회 논문집 학회본부
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• pp.435-438
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• 1991

This work is aimed to clarify the effect of only crosslinking of polyethylene on the water tree propagation and thus the crosslinking of LDPE was made by use of $Co^{60}$ $\gamma$-ray irradiation at room temperature. For this purpose, before water tree testing under same test conditions, injection molded samples were made of LDPE using CNRS laboratory model and also some of them were irradiated under different dose rate for crosslinking. Afterwards, the aged specimens were put into microscopic investigation as a mean to compare their different morphological aspects by use of SEM for the fractured surface. The SEM observation points out that the untreed region in the irradiated PE shows the densed structure whereas that in the LDPE is not closely packed. Also in the water treed region of LDPE, the density and the dimension of voids are higher than those in irradiated PE. Based on our results, it seems that the difference in the PE structure could sufficiently contribute to cause the different water tree propagation of these materials.

• 대한기계학회논문집A
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• 제30권7호
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• pp.857-864
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• 2006

Various compressive specimens were fabricated using autoclave do-gassing moulding to find out the compressive characteristics of the carbon/epoxy plain weave fabric composites with respect to the bias and shear angles. The stacking angles of the bias specimens are $[0]_{10T,}\;[3]_{10T,}\;[6]_{10T,}\;[9]_{10T,}\;[12]_{10T,}\;[15]_{10T,}\;[30]_{10T,}\;[45]_{10T}$ and those of the sheared specimens are $[{\pm}37]_{10T,}\;[{\pm}32]_{10T,}\;[{\pm}28]_{10T,}\;[{\pm}22]_{10T,}$ respectively. In order to verify the effect of micro-tow structures on compressive strength and modulus of the composites, compressive test specimens of uni-directional carbon/epoxy composites with the same materials and the same stacking conditions were fabricated. The modulus and strength of both types of composite specimens were compared with the prediction results based on the CLPT and a proposed strength formula. The tow deformation and fracture modes were investigated by microscopic observation.

• 생명과학회지
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• 제12권4호
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• pp.490-495
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• 2002

병원성 미생물인 Vibrio fluvialis로부터 hemolysin을 분리정제 하였다. 즉, hemolysin의 정제는 균 배양액을 황산암모늄, ion exchange chromatography를 행하였으며 SDS-PAGE를 통해 그 단백질의 크기가 약 79kDa임을 알게되었다. 정제된 hemolysin (VFH)는 35$^{\circ}C$에서 최적활성을 나타내었고, 4$0^{\circ}C$에서는 그 활성이 감소되었다. RTG-2 어류유래 세포주에 hemolysin (VFH)의 처리로 세포독성을 측정한 결과 50$\mu\textrm{g}$의 VFH가 약 80%의 cell line을 사멸시켰다. 또한 현미경을 통한 관찰에서도 세포의 형태변화를 관찰할 수 있었다.

• Fibers and Polymers
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• 제3권1호
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• pp.1-7
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• 2002

Cellulose carbonate was prepared by the reaction of cellulose pulp and $CO_2$ with treatment reagents, such as aqueous $Zncl_2$ (20-40 wt%) solution, acetone or ethyl acetate, at -5-$0^{\circ}C$ and 30-40 bar ($CO_2$) for 2 hr. Among the treatment reagents, ethyl acetate was the most effective. Cellulose carbonate was dissolved in 10% sodium hydroxide solution containing zinc oxide up to 3 wt% at -5-$0^{\circ}C$. Intrinsic viscosities of raw cellulose and cellulose carbonate were measured with an Ubbelohde viscometer using 0.5 M cupriethylenediamine hydroxide (cuen) as a solvent at $20^{\circ}C$ according to ASTM D1795 method. The molecular weight of cellulose was rarely changed by carbonation. Solubility of cellulose carbonate was tested by optical microscopic observation, UV absorbance and viscosity measurement. Phase diagram of cellulose carbonate was obtained by combining the results of solubility evaluation. Maximum concentration of cellulose carbonate for soluble zone was increased with increasing zinc oxide content. Cellulose carbonate solution in good soluble zone was transparent and showed the lowest absorbance and the highest viscosity. The cellulose carbonate and its solution were stable in refrigerator (-$5^{\circ}C$ and atmospheric pressure).