• 한국응용곤충학회지
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• 제46권2호
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• pp.325-330
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• 2007

다양한 엽채류에 발생하며 특히 상추에 피해가 큰 민달팽이는 여러 가지 식품자재 중 맥주와 오이즙액에 가장 효과적으로 유인되었다. 하지만, 이들 재료는 민달팽이를 유인할 뿐 살충효과는 전혀 없었다. 민달팽이 유인재료에 살충효과를 나타내는 물질들을 첨가하였을 때 맥주와 담배가루 혼합액의 민달팽이 유인 포살효과가 가장 높았다. 맥주 50ml에 담배 1개비 가루를 혼합하여 작은 플라스틱 용기에 담고 지표면에 매몰한 결과 하룻밤 사이에 평균 25 마리의 민달팽이가 유인 포살되는 것으로 나타났다. 하지만, 민달팽이 유인효과가 높았던 오이즙액에 담배가루를 혼합한 처리구에서는 평균 4.3마리만 유살되었다. 맥주와 담배 혼합액을 민달팽이가 심하게 발생된 상추 재배하우스에 3일간 연속으로 처리한 결과 68.4%의 방제효과를 나타내었으며, 상추 육묘상에서는 58.3%의 방제효과를 보였다. 본 연구에서 개발된 트랩은 매일 작업을 해야 하는 번거로움이 있으나 민달팽이의 피해가 큰 친환경 유기농 채소 생산농가의 육묘장이나 본포장 등 제한된 면적에서는 활용가치가 높을 것으로 기대된다.

• 소성∙가공
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• 제7권2호
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• pp.139-149
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• 1998

The technology of Semi-Solid Forging(SSF) has been actively developed to fabricate near net shape products using light and hardly formable materials. Generally the SSF process is composed of slug is compressed during a certain holding time in order to completely fill the die cavity and accelerate the solidification rate. The decision of compression time is important since it can affect microstructural characteristics, mechanical properties and shape of products.. In order to determine it proper overall heat transfer coefficient between the slug and dies should be investigated. This paper presents the procedure to find the overall heat transfer coefficient between the slug and dies by nonlinear optimization of temperature and solid fraction for a cylindrical slug at compression step in closed-die semi-solid forging. In finite ele-ment heat transfer analysis release of latent heat during solidification was considered. The influence of the predicted compression time on miscrostructural characteristics mechanimcal properties and shape of products is finally investigated by experiment.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 1995년도 추계학술대회 논문집
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• pp.199-203
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• 1995

The technology of Semi-Solid Forging (SSF) has been actively developed to fabricate near-net- shape products using light and hardly formable materials, the SSF process is composed of slug heating, forming, compression holding and ejecting step. After forming step in SSF, the slug is compressed during a certain holding time in order to be completely filled in the die cavity and be accelerated in solidification rate. The compression holding time that can affect mechanical properties and shape of products is important to make decision, where it is necessary to find overall hert transfer coefficeient properly which has large effect on heat transfer between slug and die. This paper presents the procedure to predict compression holding time of octaining the final shaped part with information of temperature and solid fraction for a cylindrical slug at compression hoiding step in closed-die compression process using heat transfer analysis considering latent heat by means of finite element method. The influence of the predicted compression hoiding time on mechanical properties of products is finally investigated by experiment.

• Journal of Applied Biological Chemistry
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• 제59권1호
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• pp.25-29
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• 2016

B형 간염 바이러스는 간경변증과 간세포암의 원인이 되는 간섬유화를 유발한다. 하지만 현재까지 그와 관련한 자세한 메커니즘은 밝혀지지 않았기에 본 연구에서 이를 알아보고자 하였다. 실험 결과, B형 간염 바이러스에서 발현되는 HBx 단백질에 의해 vimentin, fibronectin, slug, snail, NOX4가 증가되는 것을 확인하였다. NOX4에 의한 활성산소가 snail, slug 발현을 유도하고 섬유화 과정을 촉진할 수 있기 때문에 NOX4의 발현을 유도하는 HBx가 간섬유화를 조절, 유도하는 것을 확인하였다.

• Applied Microscopy
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• 제25권3호
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• pp.40-50
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• 1995

The results of observation on the salivary gland and salivary secretory duct of Korean slug, Incilaria fruhstorferi, in histochemical method are as follows. It is observed that there are six kinds of gland cells(Type-A, B, C, E and F) making up the salivary gland of Korean slug. Of those, type-A gland cell is observed as an acid mucous cell, and type-B, C, D, F gland cells as neutral mucous cells. But in type-E gland cell, while the membrane surrounding granules exhibit alcianophilia, granules show no reaction. The salivary secretory duct composing the salivary gland of Korean slug is composed of supporting epithelial cell and four kinds of gland cells(type-A, E, F and G), of which type-A, E, F gland cells compose both the acinus of salivary gland and endothelial tissue of salivary secretory duct, and are secreted into lumen through salivary secretory duct. But, type-G gland cell is observed only in the endothelium of salivary secretory duct and mucous granules are observed as neutral mucopolysaccharide.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 1997년도 고액공존금속의 성형기술 심포지엄
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• pp.174-182
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• 1997

The technology of Semi-Solid Forging (SSF) has been actively developed to fabricate near-net-shape products using light and hardly formable materials. Generally, the SSF process is composed of slug heating, forming, compression -holding and ejecting step. After forming step in SSF, the slug is compressed during a certain holding time in order to be completely filled in the die cavity and be accelerated in solidification rate. The compression holding time that can affect microstructural characteristics and shape of products is important to make decision, where it is necessary to find overall heat transfer coefficient properly which has large effect on heat transfer between slug and die. This paper presents the procedure to predict compression holding time of obtaining the final shaped part with information of temperature and solid fraction for a cylindrical slug at compression holding step in closed-die compression process using heat transfer analysis considering latent heat by means of finite element method. The influence of the predicted compression holding time on microstructural characteristics of products is finally investigated by experiment.

• Molecules and Cells
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• 제39권12호
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• pp.909-914
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• 2016

Epithelial-mesenchymal transition (EMT) is a critical step in the acquisition of the migratory and invasive capabilities associated with metastatic competence. Cysteine-rich protein 61 (CCN1/Cyr61) has been implicated as an important mediator in the proliferation and metastasis of breast cancer. Hence, Cyr61 and associated pathways are attractive targets for therapeutic interventions directed against the EMT. In the present study, we report that baicalein significantly inhibits the expression of Cyr61 and migration and invasion of MDA-MB231 human breast cancer cells. Exposure to baicalein led to increased E-cadherin expression, possibly due to the ubiquitination of Snail and Slug, which was mediated by the Cyr61/Akt/glycogen synthase kinase $3{\beta}$ ($GSK3{\beta}$) pathway. Further analysis revealed that baicalein inhibited the expression of lysyl oxidase like-2 (LOXL-2), which is a functional collaborator of Snail and Slug, and subsequently attenuated the direct interaction between LOXL-2 and Snail or Slug, thereby enhancing $GSK3{\beta}$-dependent Snail and Slug degradation. Our findings provide new insights into the antimetastatic mechanism of baicalein and may contribute to its beneficial use in breast cancer therapies.

• Advances in aircraft and spacecraft science
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• 제1권4호
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• pp.409-425
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• 2014

Converging flows of a gas and a liquid at a microchannel cross junction, under proper conditions, can result in the formation of periodic, dispersed microslugs. This microslug formation phenomenon has been proposed as the basis for a fuel injection system in a novel, 'discrete' monopropellant microthruster designed for use in next-generation miniaturized satellites. Previous experimental studies demonstrated the ability to generate fuel slugs with characteristics commensurate with the intended application during steady-state operation. In this work, numerical and experimental techniques are used to study the effect of valve actuation on slug characteristics, and the results are used to compare with equivalent steady-state slugs. Computational simulations of a valve with a 1 ms valve-actuation cycle show that as the ratio of the response time of the valve to the fully open time is increased, transient effects can increase slug length by up to 17%. The simulations also demonstrate that the effect of the valve is largely independent of surface tension coefficient, which is the thermophysical parameter most responsible for slug formation characteristics. Flow visualization experiments performed using a miniature valve with a 20 ms response time showed less than a 1% change in the length of slugs formed during the actuation cycle. The results of this study indicate that impulse bit and thrust calculations can discount transient effects for slower valves, but as valve technology improves transient effects may become more significant.

• Applied Microscopy
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• 제26권1호
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• pp.33-45
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• 1996

The spermatogenesis of Korean slug, Incilaria fruhstorferi are observed by electron microscope. The results are as follows: The spermatogenesis of Korean slug, Incilaria fruhstorferi, is processed through the five stages; Spermatogonia, primary spermatocyte, secondary spematocyte, spermatid and spermatozoon. The spermiogenesis, the differentiation of the spermatid, is also processed through the five stages. In stage 1, the numerous and round mitochomdria in the cytoplasm are moved around the nucleus of spermatid. In stage 2, the nucleus of spermatid transformed into the oval shape, and the oval nucleus is surrounded by many rough endoplasmic reticulum. In stage 3, the oval nucleus of spermatid is changed to be curved as an arrow, and then two centrioles appeared behind nucleus. The centriole is sucked into the cytoplasm. and almost all the chromatins are changed into heterochromatins. In stage 4, the nucleus of spermatid are transformed into the oval shape, when the lamella plate chromatin of spermatid form in the nucleoplasm. In stage 5, the oval nucleus is then transformed into the stream-line shape when the lamella plate chromatin of spematid gradually concentrated in the nucleus, and long axoneme ($65{\mu}m$ in length) form from the distal centriole. Two long mitochondria in the middle piece and the main piece of spermatozoon array spirally along a long axoneme, and the mitochondria matrix is gradually filled with electron-dense glycogen particles ($0.1{\mu}m$ in size). The axoneme of spermatozoon consists of typical 9+2 microtubular pattern.

• BMB Reports
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• 제57권6호
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• pp.305-310
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• 2024

T-plastin (PLST), a member of the actin-bundling protein family, plays crucial roles in cytoskeletal structure, regulation, and motility. Studies have shown that the plastin family is associated with the malignant characteristics of cancer, such as circulating tumor cells and metastasis, by inducing epithelial-mesenchymal transition (EMT) in various cancer cells. However, the role of PLST in the EMT of human lung cancer cells remains unclear. In this study, we observed that PLST overexpression enhanced cell migratory and invasive abilities, whereas its downregulation resulted in their suppression. Moreover, PLST expression levels were associated with the expression patterns of EMT markers, including E-cadherin, vimentin, and Slug. Furthermore, the phosphorylation levels of focal adhesion kinase (FAK) and AKT serine/threonine kinase (AKT) were dependent on PLST expression levels. These findings indicate that PLST induces the migration and invasion of human lung cancer cells by promoting Slug-mediated EMT via the FAK/AKT signaling pathway.