• Animal cells and systems
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• 제2권1호
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• pp.81-86
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• 1998

Recent identification and characterization of plant homeobox genes suggest that they play important roles in morphogenetic events. OSH1, one of the rice homeobox genes, is thought to be related to organ development since the changes of OSH1 gene expression cause morphological abnormalities of leaves by the ectopic expression and is expressed during early embryogenesis. In this experiment, the expression pattern of OSH1 was analyzedinmutants by in situ hybridization, and OSH1's potential as a molecular marker was explored. Region-specific expression of OSH1 during early embryogenesis shows that OSH1 could be used as a molecular marker for characterizing embryo mutants. Although several organless and shootless mutants showed normal expression of OSM1, some mutants exhibited abnormal expression patterns. In a minute organless cle1-1 embryo whose epidermis resembled morphologically the epithelium of scutellum, OSH1 expression was limited to a small basal region. This expression pattern suggests the gross deletion of the basal part. In a radicleless mutant, odm115, OSH1 expression was detected in a basal region instead of subcentral region of the ventral side. Together with other characteristics (short embryo and normal adventitious roots), odm115 was estimated to be derived from the deletion of basal region. Among five shootless mutants, three showed normal expression of OSH1. In the shl2 embryo, no expression of OSH1 was observed. In the shl1 embryo, however, OSH1 expression was extended to a dorsal side, indicating that SHL2 might be related to dorsoventral patterning. The above results of in situ hybrydization clearly indicate that OSH1 can be utilized as a marker for characterizing gene functions of embryo mutants.

• Corrosion Science and Technology
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• 제17권2호
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• pp.68-73
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• 2018

Substitution of hip and knee joints by CoCr alloys is in great demand due to their high wear resistance and good biocompatibility. Understanding of tribocorrosion in joint replacements requires study of variables such as coefficient of friction and the choice of a proper corrosive medium in wear-corrosion tests carried out in the lab. The objective of this study was to characterize tribocorrosion behaviour of CoCr alloy with low (LCCoCr) and high carbon (HCCoCr) contents in several corrosive media: NaCl, Phosphate Buffer Solution (PBS), and PBS with hyaluronic acid (PBS-HA). Tribocorrosion tests were carried out on a pin-on-disk tribometer with an integrated electrochemical cell. A normal load of 5N was applied on the alumina ball counterpart at a rotation rate of 120 rpm. Coefficient of friction (COF) was measured and tribocorrosion behaviour was characterized by in situ application of electrochemical techniques. HCCoCr alloy immersed in PBS-HA showed the best tribocorrosion behaviour with the lowest COF. In this case, in situ measurement of corrosion potential and the impedance data under wear corrosion process showed an active state while passive film was continuously destroyed without possibility of regeneration.

• 한국가축번식학회지
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• 제24권4호
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• pp.385-394
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• 2000

돼지 원시 생식세포를 미성숙 성선에서 분리하고 체외 배양하여 EG 세포를 얻으려 할 경우 , 상당수의 세포들이 배양초기에 손실을 입게 된다. 이러한 돼지 원시 생식세포의 체외 손실 원인을 규명하고자, 미성숙 성선에서 분리된 세포를 부유 배양을 하고 FACS (fluorescent activated cell sorter)를 이용한 DNA 절편 분석법으로 apoptosis를 관찰한 결과 체외 배양된 처리구에서 apoptosis가 증가되었다. 그러나, 미성숙 성선에서 분리된 세포는 원시 생식세포와 체세포가 혼합된 세포들이므로, apoptosis가 일어난 돼지 원시 생식세포를 다른 체세포들로부터 구분하기 위하여 0 시간부터 24 시간까지 배양된 세포를 대상으로 정량 TUNEL 분석을 시행하였다. 이 결과, alkaline phosphatase 활성과 in situ TUNEL 분석을 통하여 apoptosls 가 일어난 돼지 원시 생식세포가 시간이 경과함에 따라 증가되었다. 이러한 결과들을 종합하여 볼 때 apoptosis가 돼지 원시 생식세포의 체외 손실의 원인 중 하나임을 규명하였다.

• Restorative Dentistry and Endodontics
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• 제29권4호
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• pp.399-408
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• 2004

Odontoblasts are responsible for the formation and maintenance of dentin. They are known to synthesize unique gene products including dentin sialophosphoprotein (DSPP). Another unique genes of the cells remain unclear. OD314 was isolated from the odontoblasts/pulp cells of rats and partially characterized as an odontoblast-enriched gene (Dey et al., 2001). This study aimed to elucidate the biological function of OD314, relating to odontoblast differentiation and dentinogenesis. After determining the open reading frame (ORP) of OD314 by transient transfection analysis using green fluorescent protein (GPP) expression vector, mRNA in-situ hybridization, immunohistochemistry, reverse transcription-polymerase chain reaction (RT-PCR) and western analysis were performed. The results were as follows: 1. In in-situ hybridization, OD314 mRNAs were expressed in odontoblasts of developing coronal and root pulp. 2. OD314 was a novel protein encoding 154 amino acids, and the protein was mainly expressed in cytoplasm by transient transfection analysis. 3. Mineralized nodules were associated with multilayer cell nodules in the culture of human dental pulp cells and first detected from day 21 using alizarin-red S staining. 4. In RT-PCR analysis, OD314, osteocalcin (OC) and DSPP strongly expressed throughout 28 days of culture. Whereas, osteonectin (ON) mRNA expression stayed low up to day 14, and then gradually decreased from day 21. 5. Western blots showed an approximately 17 kDa band. OD314 protein was expressed from the start of culture and then increased greatly from day 21. In conclusion, OD314 is considered as an odontoblast-enriched gene and may play important roles in odontoblast differentiation and dentin mineralization.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2010년도 추계 학술발표회
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• pp.269-281
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• 2010

The cone penetration test(CPT) has been increasingly used for in situ site characterization. However, the use of CPT is often limited due to specific site conditions depending on the cone size, geometry, and capacity of the CPT system used. In South Korea, it has generally been considered that the CPT could be satisfactorily performed only in soft soils. Louisiana State University/ Louisiana Transportation Research Center has implemented a field-rugged continuous intrusion miniature cone penetration test (CIMCPT) system since the 1990s. The miniature cone penetrometer of the CIMCPT system has a cross-sectional cone area of $2cm^2$ allowing finer soil profiles compared to the standard $10cm^2$. The reduced cross-sectional area also enables a system capacity reduction leading to cost saving and ease in maintenance. In addition, the continuous intrusion mechanism allows fast and economic site investigations. Samsung C&T Corporation has recently implemented a similar CIMCPT system. In this study, case studies on the field application of Samsung CIMCPT system for the last 2 years are presented to illustrate its performance investigation and its usefulness and limitation. Results of the case studies show that the CIMCPT system can be applied to soils with cone tip resistance($q_c$) values up to about 30MPa and allows a reliable and useful way to characterize soft soils. The results also show that the rod buckling limits the investigation depth by the system and the large contact pressure of the CIMCPT truck prevents the use of the system at sites with soft surface soils. According to the results of the case studies, the Samsung CIMCPT system has been being upgraded with a miniature cone with a longer rod, a crawler-type transportation system, a pre-boring system, and so on.

• 한국전기전자재료학회논문지
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• 제19권10호
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• pp.923-929
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• 2006

Single crystalline ZnO films were successfully grown on R-plane sapphire substrates by plasma-assisted molecular beam epitaxy. Epitaxial relationship between the ZnO film and the R-plane sapphire was determined to be $[-1101]Al_2O_3{\parallel}[0001]ZnO,\;[11-20]Al_2O_2{\parallel}[-1100]ZnO$ based on the in-situ reflection high-energy electron diffraction analysis and confirmed again by high-resolution X-ray diffraction measurements. Grown (11-20) ZnO films surface showed mound-like morphology along the <0001>ZnO direction and the RMS roughness was about 4 nm for $2{\mu}m{\times}2{\mu}m$ area.

• 센서학회지
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• 제13권4호
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• pp.277-281
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• 2004

$Hg_{1-x}Cd_{x}Te$ (MCT) was grown by hot wall epitaxy. Prior to the MCT growth, the CdTe (111) buffer layer was grown on the GaAs substrate at the temperature of $590^{\circ}C$ for 15 min. When the thickness of the CdTe buffer layer was $5{\mu}m$ or thicker, the full width at half maximum values obtained from the x-ray rocking curves were found to significantly decrease. After a good quality CdTe buffer layer was grown, the MCT epilayers were grown on the CdTe (111)/GaAs substrate at various temperatures in situ. The crystal quality for those epilayers was investigated by means of the x-ray rocking curves and the photocurrent experiment. The photoconductor characterization for the epilayers was also measured. The energy band gap of MCT was determined from the photocurrent measurement and the x composition rates from the temperature dependence of the energy band gap were turned out.

• 한국재료학회:학술대회논문집
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• 한국재료학회 2003년도 추계학술발표강연 및 논문개요집
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• pp.152-152
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• 2003

Hg$\sub$l-x/Cd$\sub$x/Te (MCT) was grown by hot wall epitaxy. Prior to the MCT growth, the CdTe (111) buffer layer was grown on the GaAs substrate at the temperature of 590$^{\circ}C$ for 15 min. When the thickness of the CdTe buffer layer was 5 $\mu\textrm{m}$ or thicker, the full width at half maximum values obtained from the x-ray rocking curves were found to significantly decrease. After a good quality CdTe buffer layer was grown, the MCT epilayers were grown on the CdTe (111) /GaAs substrate at various temperatures in situ. The crystal quality for those epilayers was investigated by means of the x-ray rocking curves and the photocurrent experiment The photoconductor characterization for the epilayers was also measured The energy band gap of MCT was determined from the photocurrent measurement and the x composition rates from the temperature dependence of the energy band gap were turned out

• 대한전기학회:학술대회논문집
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• 대한전기학회 2001년도 하계학술대회 논문집 C
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• pp.1402-1404
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• 2001

Josephson junction arrays of the type $Nb/Al-Al_2O_3/Nb$ were prepared by DC magnetron sputtering. The tunnel barrier was formed by in-situ thermal oxidation. Individual junctions were defined using selective niobium etching process(SNEP). The characteristic curves of Josephson junction arrays fabricated with and without cooling the substrate were represented. The junctions deposited without cooling showed poor characteristics(high leakage current, low gap voltage), and a high quality Josephson junction array of 2,000 junctions with high hysteresis was obtained with cooling and when operated at 74.6 GHz, it generated stable quantized voltage steps up to 2.2 V.

• 반도체디스플레이기술학회지
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• 제19권1호
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• pp.93-96
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• 2020

Polyimide thin film was prepared by annealing the polyamic acid that was synthesized through co-deposition of diamine and dianhydride. The polyamic acid and polyimide thin film were characterized with FT-IR and HR FE-SEM. The average roughness of the film surface, evaluated with AFM, were 0.385 nm and 0.299 nm after co-deposition, and annealing at 120 ℃ respectively. OLED was passivated with the polyimide layer of 200 nm thickness. While the inorganic passivation layer enhances the WVTR of OLED, the organic passivation layer gives flexibility to the OLED. The in-situ passivation of OLED with organic thin film layer provides the leading technique to develop flexible OLED Display.