• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2005년도 춘계학술대회 논문집
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• pp.1168-1170
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• 2005

Nanoimprint Lithography(NIL) has increasingly been recognized as a key manufacturing technology for nanosized feature. One of the most important task for nanoimprint lithography is to provide the imprinting stamp with low price. The Stamp fabricated with Si based material by e-beam lithography, RIE is extremely expensive and its throughput is very limited and PDMS replica is too soft to hold high imprinting pressure.(>5atm) In this study, we present the imprinting stamp which can be easily replicated from original mold and is based on PVC film. Replication of original Si mold to PVC film was done by Hot embossing technique, ($120^{\circ}C$ of Temperature, 20 atm applied) As small as 100nm patterns were successfully transferred into PVC film. The size of stamp was up to 100mm in diameter.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2009년도 춘계학술대회 논문집
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• pp.290-293
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• 2009

This paper presents the development of a disposable label-free biosensor for bio molecular interaction analysis. Label-free biosensors have advantages of high performance in sensitivity and short detection time. Among various label-free systems, we introduced biosensor with nano grating structures based on white light source and spectrometer. And to develop high efficiency label-free biosensor, we suggest replicating processes satisfying required specification. We also report a system set-up to evaluate the characteristics of phenomenon shown in this biosensor system.

• Molecules and Cells
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• 제40권2호
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• pp.83-89
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• 2017

Error-free replication and repair of DNA are pivotal to organisms for faithful transmission of their genetic information. Cells orchestrate complex signaling networks that sense and resolve DNA damage. Post-translational protein modifications by ubiquitin and ubiquitin-like proteins, including SUMO and NEDD8, are critically involved in DNA damage response (DDR) and DNA damage tolerance (DDT). The expression of interferon-stimulated gene 15 (ISG15), the first identified ubiquitin-like protein, has recently been shown to be induced under various DNA damage conditions, such as exposure to UV, camptothecin, and doxorubicin. Here we overview the recent findings on the role of ISG15 and its conjugation to target proteins (e.g., p53,$ {\Delta}Np63{\alpha}$, and PCNA) in the control of cellular responses to genotoxic stress, such as the inhibition of cell growth and tumorigenesis.

• Design & Manufacturing
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• 제2권2호
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• pp.29-32
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• 2008

A back light unit (BLU) is a key module of a thin film transistor liquid crystal display (TFT-LCD), frequently utilized in various mobile displays. In this study, we experimentally characterize transcription and optical properties of concave and convex microlens arrays (MLAs) of light guide plate (LGP) fabricated by injection molding with polycarbonate as a LGP substrate material. Nickel mold inserts were manufactured by electroforming on the MLA which was fabricated by the thermal reflow of photoresist microstructures patterned by UV-photolithography. For the case of convex microlens, the height of replicated microlens was less than that of the mold insert while maintaining almost the same microlens diameter of the mold insert as the location of the microlens is far from the gate. In contrast, for the concave microlens, the diameter of replicated microlens was larger than that of mold insert, while showing almost the same microlens height as the mold insert. From the optical examination of replicated convex and concave MLAs, it was found that a higher luminance of the LGP was achieved by the concave MLAs compared to the convex MLAs (about 30% enhancement in this case)due to the utilization of a larger amount of light provided by the light sources.

• 분석과학
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• 제29권4호
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• pp.202-208
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• 2016

A novel and simple method for detecting seven organic acids (formic acid, malic acid, lactic acid, acetic acid, citric acid, fumaric acid and propionic acid) in animal feed using high performance liquid chromatography equipped with a photo-diode array detector (HPLC/PDA) was developed. The chromatographic peaks of the seven organic acids were successfully identified by comparing their retention times and UV spectra with reference standards. Method validation was performed in terms of linearity, sensitivity, selectivity, accuracy, and precision. The limits of detection (LODs) for the instrument employed in these experiments ranged from 12 to 8,026 μg/kg, and the limits of quantification (LOQs) ranged from 43 to 26,755 μg/kg. Average recoveries of the seven organic acids ranged from 79.3 to 95.2 %. Method replication resulted in intra- day and inter-day peak area variation of <3.2 %. The developed method was specific and reliable and is therefore suitable for the routine analysis of organic acids in animal feed.

• 한국자기공명학회논문지
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• 제3권1호
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• pp.60-70
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• 1999

The pyrimidine(6-4) pyrimidone photoproduct [(6-4) adduct] is one of the major photoproducts induced by UV irradiation of DNA and occurs at TpT sites. The (6-4) adduct is highly mutagenic and specific during translesion replication. The marked preference for insertion of A opposite the 5'-T and G opposite the 3--T of the (6-4) adducts leads to a predominantly 3'-T\longrightarrowC transition with 85% replicating error rate. In order to obtain insight into the origin of 3'-T\longrightarrowC transition induced by the (6-4) adduct, we have performed one - and two-dimensional NMR experiment. The 3'-Tof the (6-4) lesion forms the stable hydrogen bonding to the imino proton of an opposed G, which stabilizes the overall helix and diminishes the highly distorted conformation caused by the (6-4) lesion in the (6-4)/AA duplex. We proposed that the greater insertion of a G over an A opposite the 3'-T of the (6-4) lesion These results may account for the greater preference for the insertion of a G over a A opposite the 3'-T of the (6-4) lesion. Thus this insertion leads to the highly specific 3'-T\longrightarrowC multation at the (6-4) lesion site.

• 미생물학회지
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• 제31권1호
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• pp.79-84
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• 1993

Infection of Chinook Salmon Embryo (CHSE) cells with IPNV resulted in a significant decrease in intracellular free calcium concentration ([$Ca^{2+}$]i) compared to mock-infected cells. The degree of the decrease in [Ca$^{2+}$]i was dependent on the amount of input virus, and treatment of IPNV-infected CHSE cells with metabolic inhibitors such as cyloheximide cordycepin partially reversed the decrease in [$Ca^{2+}$]i in IPNV-infected cells. Inactiation of PINV with UV also abolished IPNV-induced decrease in [$Ca^{2+}$]i. These data suggest an active role of IPNV in the decrease of [Ca$^{2+}$]i in the infected CHSE cells. The importance of the decrease in [$Ca^{2}$i] could be supported by the finding that the production of IPNV plaques increased in the cells treated with verapamil, a calcium influex blocker, and by lowering the concentration of extracellular calcium. Decreased production of IPNV plaques was observed by elevating the extracellular calcium. Thus, it is suggested that IPNV induced a decreased in [$Ca^{2+}$]i and the decrease in [$Ca^{2+}$]i may plan an importat role in efficient replication of IPNV.ation of IPNV.

• The Plant Pathology Journal
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• 제33권4호
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• pp.429-433
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• 2017

Chrysanthemums (Chrysanthemum morifolium) are susceptible to tobacco mosaic virus (TMV). TMV-based expression vectors have been used in high-throughput experiments for production of foreign protein in plants and also expressing green fluorescent protein (GFP) to allow visualization of TMV movement. Here, we used TMV expressing the GFP to examine the infection of chrysanthemum by a TMV-based expression vector. Viral replication, movement and GFP expression by TMV-GFP were verified in upper leaves of chrysanthemums up to 73 days post inoculation (dpi) by RT-PCR. Neither wild-type TMV nor TMV-GFP induced symptoms. GFP fluorescence was seen in the larger veins of the inoculated leaf, in the stem above the inoculation site and in petioles of upper leaves, although there was no consistent detection of GFP fluorescence in the lamina of upper leaves under UV. Thus, a TMV-based expression vector can infect chrysanthemum and can be used for the in vivo study of gene functions.

• 한국환경농학회지
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• 제27권4호
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• pp.435-440
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• 2008

E. coli, S. agalactiae, S. aureus는 젖소의 유방염을 유발하는 주요 원인균들이다. 이 균들은 분변 혹은 우유에 존재하며, 감염되지 않은 다른 개체로의 감염을 유발한다. 자외선은 소독제로서 이미 산업계 및 의료계에서 쓰레기 및 물의 살균에 사용되고 있으므로, 자외선을 이용하여 젖소의 유방염 확산을 방지하는 것의 실효성을 검증하였다. 분변의 함수율은 젖소 유방염 유발균의 증식에 영향을 미치지 않았고, 144시간 이상의 장시간 생존이 가능함을 확인하였다. 자외선의 조사 시, 조사하는 동안 우분뇨 및 톱밥을 교반하는 것이 교반하지 않는 것보다 균의 증식을 억압하는 것을 확인할 수 있었다. 한편, 자외선의 살균력은 함수율이 낮을수록, 조사시간이 길수록, 조사거리가 짧을수록 더 증가하는 것을 확인할 수 있었다. 본 실험을 통해 얻은 함수율, 조사시간, 조사거리, 교반 여부에 대한 결과는 환경 유래, 특히 우분뇨 유래 젖소 유방염의 감염을 예방하고자 할 때 자외선 살균기의 적용이 가능할 것이며, 현장에 적용할 살균기의 제작에 중요한 기초 자료로서 활용될 것이다.

• 한국균학회지
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• 제41권1호
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• pp.1-8
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• 2013

Cop9 signalosome(CSN)은 최초 식물 발달 과정에서의 빛에 의한 전사 조절 과정에서의 억제 유전자로 처음 분리된 이후 이들이 다양한 진핵 생물 에서 매우 잘 보존되어 있음이 알려지게 되었다. 이들은 대부분 8개의 subunit으로 구성되며 26S proteasome lid와 eIF3와 구조적으로는 물론 기능적으로도 유사성을 보인다고 알려져 있다. 이들은 특히 Cullin-Ring ubiquitin ligases(CRL)의 구성 요소인 Cullin의 deneddylation을 매개하여 ubiquitin ligase의 활성을 조절한다고 알려져 있으며, 또한 세포 주기 및 checkpoint 조절에 관여한다고 보고되었다. 분열효모의 경우 CSN1 및 CSN2 결손 세포에서 S-phase로서의 진행이 지연됨이 관찰되었고 감마선 혹은 UV에 좀더 민감해지는 현상이 관찰되어 CSN이 checkpoint 조절에 관여한다는 것을 보여주었다. 곰팡이의 CSN 경우 구조적으로 더욱 상위 개체들의 그것과 더욱 유사한데, CSN이 생체 시계 리듬, 빛과 연관한 호르몬 생산, 곰팡이의 발달 과정 및 생식 주기를 조절함이 보고되었다. 또한 Aspergillus nidulans의 경우 상위개체에서 보여준 DNA 합성 및 손상, 세포 주기 조절에서의 기능이 알려지면서 CSN은 곰팡이 생활사에 필수적인 여러 과정들을 조절하는 중요한 인자임을 알 수 있다. 이로써 식물이나 포유동물 등에서 보고되었던 CSN의 주요 기능을 미생물에서도 대부분 공유하고 있음을 알 수 있고 이들이 CRL을 통한 주요 세포 활성 조절 연구에 좋은 툴로서 활용할 수 있음을 시사하고 있다.