• 방사선산업학회지
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• 제5권1호
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• pp.15-20
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• 2011

Protein kinases are the most important drug targets for the treatment of numerous diseases. The involvement of protein kinase C (PKC) in many biological processes such as development, memory, cell differentiation, and proliferation has been demonstrated. PKC is recognized as an important player in carcinogenesis. Thus, a variety of PKC inhibitors have been investigated. Among them, flavonoids have been demonstrated to affect the activity of many mammalian in vitro enzyme systems. The recent investigation was performed to evaluate the inhibitory effects of hesperidin, which is a flavonoid, on the proliferation and carcinogenesis of many cancers. In this study, an efficient kinase assay based on a biochip using radio-phosphorylation was established and performed for an examination of the inhibitory effects of hesperidin on PKC activity at different concentrations of 50, 200, 500 nM. It was found that hesperidin shows inhibitory potency on PKC, and that the biochip can be used to rapidly screen kinase inhibitors resulting in the therapeutic agents.

• 방사선산업학회지
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• 제3권1호
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• pp.25-29
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• 2009

Microarrays can be used to screen thousands of binding events in a parallel and high throughput fashion and are of major importance in disease diagnosis and drug discovery. The use of radioisotope is conventionally regarded as one of the most sensitive detection methods. Atherosclerosis is a common disorder affecting arterial blood vessels. It happens when fat, cholesterol, and other substances made in the arterial blood vessels form a hard substances called plaque. Lipoprotein-associated phospholipase $A_2$ ($Lp-PLA_2$), a phospholipase $A_2$ enzyme, is used as a marker for cardiac disease. The detection of $Lp-PLA_2$ was accomplished by using radioactive [$^3H-acetyl$] PAF as a substrate and a feasibility study on RI biochip application to detection of $Lp-PLA_2$, a risk factors of atherosclerosis was performed. Inhibitive activity of a native plant extract was also determined by using the RI biochip. It was found to be applicable to a high-throughput screening of inhibitors for developing atherosclerosis therapeutic agents.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2004년도 ICCAS
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• pp.196-201
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• 2004

In biometric and biomedical applications, a special transporting mechanism must be designed for the ${\mu}$TAS (micro total analysis system) to move samples and reagents through the microchannels that connect the unit procedure components in the system. An important issue for this miniaturization and integration is microfluid management technique, i.e., microfluid transportation, metering, and mixing. In view of this, this study presents an optimal fuzzy sliding-mode control (OFSMC) design based on the 8051 microprocessor and implementation of a complete microfluidic manipulated system implementation of biochip system with a pneumatic pumping actuator, a feedback-signal photodiodes and flowmeter. The new microfluid management technique successfully improved the efficiency of molecular biology reaction by increasing the velocity of the target nucleic acid molecules, which increases the effective collision into the probe molecules as the target molecules flow back and forth. Therefore, this hybridization chip was able to increase hybridization signal 6-fold and reduce non-specific target-probe binding and background noises within 30 minutes, as compared to conventional hybridization methods, which may take from 4 hours to overnight. In addition, the new technique was also used in DNA extraction. When serum existed in the fluid, the extraction efficiency of immobilized beads with solution flowing back and forth was 88-fold higher than that of free-beads.

• 한국재료학회:학술대회논문집
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• 한국재료학회 2003년도 추계학술발표강연 및 논문개요집
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• pp.71-71
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• 2003

Hot embossing has been widely accepted as an alternative to photolithography in generating patterns on polymeric substrates. The optimization of embossing process should be accomplished based on polymer substrate materials. In this paper, the effect of polymer substrates on nano scale hot embossing process was studied. Silicon molds with nano size patterns were fabricated by e-beam direct writing. Molds were coated with self-assembled monolayer (SAM) of (1, 1, 2.2H -perfluorooctyl)-trichlorosilane to reduce the stiction between mold and substrates. For an embossing, pressure of 55, 75 bur, embossing time of 5 min and temperature of above transition temperature were peformed. Polymethylmethacrylates (PMMA) with different molecular weights of 450,000 and 950,000, MR-I 8010 polymer (Micro Resist Technology) and polyaliphatic imide copolymer were applied for hot embossing process development in nano size. These polymers were spun coated on the Si wafer with the thickness between 150 and 200 nm. The nano size patterns obtained after hot embossing were observed and compared based on the polymer properties by scanning electron microscopy (SEM). The imprinting uniformity dependent on the Pattern density and size was investigated. Four polymers have been evaluated for the nanoimprint By optimizing the process parameters, the four polymers lead to uniform imprint and good pattern profiles. A reduction in the friction for smooth surfaces during demoulding is possible by polymer selection.

• 한국재료학회지
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• 제16권4호
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• pp.225-230
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• 2006

Nanoimprint lithography (NIL) is a novel method of fabricating nanometer scale patterns. It is a simple process with low cost, high throughput and resolution. NIL creates patterns by mechanical deformation of an imprint resist and physical contact process. The imprint resist is typically a monomer or polymer formulation that is cured by heat or UV light during the imprinting process. Stiction between the resist and the stamp is resulted from this physical contact process. Stiction issue is more important in the stamps including narrow pattern size and wide area. Therefore, the antistiction layer coating is very effective to prevent this problem and ensure successful NIL. In this paper, an antistiction layer was deposited and characterized by PECVD (plasma enhanced chemical vapor deposition) method for metal stamps. Deposition rates of an antistiction layer on Si and Ni substrates were in proportion to deposited time and 3.4 nm/min and 2.5 nm/min, respectively. A 50 nm thick antistiction layer showed 90% relative transmittance at 365 nm wavelength. Contact angle result showed good hydrophobicity over 105 degree. $CF_2$ and $CF_3$ peaks were founded in ATR-FTIR analysis. The thicknesses and the contact angle of a 50 nm thick antistiction film were slightly changed during chemical resistance test using acetone and sulfuric acid. To evaluate the deposited antistiction layer, a 50 nm thick film was coated on a stainless steel stamp made by wet etching process. A PMMA substrate was successfully imprinting without pattern degradations by the stainless steel stamp with an antistiction layer. The test result shows that antistiction layer coating is very effective for NIL.

• 토지주택연구
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• 제3권3호
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• pp.299-305
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• 2012

음식물쓰레기 발효 소멸용 목질바이오칩의 종류별로 세공구조에 따른 음식물쓰레기 무게 감량율 및 미생물 활동성을 비교분석 하였다. 목질바이오칩을 이용한 음식물쓰레기 발효 소멸실험을 온도 $30{\sim}50^{\circ}C$, 습도 30~70% 조건의 발효 소멸 반응조에 15일간 매일 700~1,500g의 음식물쓰레기를 투입하며 실시하였다. 이 때 1,500g의 목질바이오칩을 발효 소멸 반응조에 초기에 투입하였다. 실험에 사용한 목질바이오칩의 세공구조는 미생물 혼합형(A 바이오칩), $2{\mu}m$ 마크로 세공형(B biochip), $0.1{\mu}m$ 미세공형(C 바이오칩), 점성구조형(D 바이오칩)으로 4가지 유형이었다. 실험결과, A, B, C, D 바이오칩별 발효 소멸에 의한 음식물쓰레기 무게감량율은 각각 85%, 63%, 92%, 73%이었고, C 바이오칩의 경우가 음식물쓰레기 감량율 92%로 최고값을 나타내었다. 또한, C 바이오칩은 ATP/COD $3.00{\times}10^{-10}$, ATP/TN $2.31{\times}10^{-11}$로 상대적으로 타 종류의 바이오칩보다 높은 결과를 나타내었다. 이는 발효 소멸반응에서 발생되는 미생물의 서식지를 충분히 제공하여 ATP/COD 및 ATP/TN이 높아졌고 미생물의 활동성이 강화되어 발효 소멸반응이 원활하게 진행된 결과에 기인하는 것으로 분석되었다.

• 한국유전체학회:학술대회논문집
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• 한국유전체학회 2006년도 The 15th Korean Genome Organization Conference KOGO 2006 Annual Meeting
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• pp.66-66
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• 2006

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2003년도 생물공학의 동향(XIII)
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• pp.102-102
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• 2003

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2003년도 생물공학의 동향(XII)
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• pp.61-61
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• 2003

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2005년도 생물공학의 동향(XVII)
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• pp.728-729
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• 2005