Amorphous In-Ga-Zn-O (a-IGZO) thin film transistors (TFTs) with a coplanar structure were fabricated to investigate the feasibility of their potential application in large size organic light emitting diodes (OLEDs). Drain currents, used as functions of the gate voltages for the TFTs, showed the output currents had slight differences in the saturation region, just as the output currents of the etch stopper TFTs did. The maximum difference in the threshold voltages of the In-Ga-Zn-O (a-IGZO) TFTs was as small as approximately 0.57 V. After the application of a positive bias voltage stress for 50,000 s, the values of the threshold voltage of the coplanar structure TFTs were only slightly shifted, by 0.18 V, indicative of their stability. The coplanar structure TFTs were embedded in OLEDs and exhibited a maximum luminance as large as 500 nits, and their color gamut satisfied 99 % of the digital cinema initiatives, confirming their suitability for large size and high resolution OLEDs. Further, the image density of large-size OLEDs embedded with the coplanar structure TFTs was significantly enhanced compared with OLEDs embedded with conventional TFTs.

본 연구는 중소기업의 임원보수, 기업성과, 국제화에 대한 소유구조의 역할을 고찰한다. 소유와 경영의 엄격한 분리를 상정한 기존 문헌과 달리 소유와 경영이 중첩되는 임원의 주식소유에 주목한다. 임원 소유지분을 지배주주 소유지분과 분리․취급함으로써 임원보수, 기업성과, 국제화에 미치는 소유지분의 순효과를 임원과 지배주주의 몫으로 분해하여 측정할 수 있다. 이에 2014~2018년 기간 비금융산업에 속하는 국내 상장 중소기업의 공시정보를 활용하여 소유지분 및 임원보수가 기업성과와 국제화에 각각 어떠한 효과를 가져오는지를 주로 분석하였다. 주요 분석 결과는 다음과 같다: (1) 임원보수는 기업성과와 국제화에 직접 영향을 미치는 요인이며, (2) 임원 지분소유는 임 원보수와 양의 상관관계를 통해 간접 경로로 기업성과와 국제화에 영향을 주고 있으나, (3) 지배주주 지분소유은 기업성과 및 국제화에 직․간접 관계가 있다고 판단하기 어렵다. 이 결과를 통해 소 유와 경영의 일치가 기업성과와 국제화에 직․간접적으로 중요한 요소라는 점을 확인할 수 있다.

Human embryonic stem (ES) cells are derived from the inner cell mass of the preimplantation embryo. Human ES cells have the capacity to differentiate into various types of cells in the body. Human ES cells are indefinite source of cells for cell therapy in various degenerative disorders including neuronal disorders. Directed differentiation of human ES cells is a prerequisite for their clinical application. The objective of this study is to develop the culture condition for the derivation of neural precursor cells from human ES cells. Neural precursor cells were derived from human ES cells in a stepwise culture condition. Neural precursor cells in the form of neural rosette structures developed into neurospheres when cultured in suspension. Suspension culture of neurospheres has been maintained over 4 months. Expressions of nestin, soxl, sox2, pax3 and pax6 transcripts were upregulated during differentiation into neural precursor cells by RT-PCR analysis. In contrast, expression of oct4 was dramatically downregulated in neural precursor cells. Immunocytochemical analyses of neural precursor cells demonstrated expression of nestin and SOX1. When induced to differentiate on an adhesive substrate, neuro-spheres were able to differentiate into three lineages of neural systems, including neurons, astrocytes and oligo-dendrocytes. Transcripts of sox1 and pax6 were downregulated during differentiation of neural precursor cells into neurons. In contrast, expression of map2ab was elevated in the differentiated cells, relative to those in neural precursor cells. Neurons derived from neural precursor cells expressed NCAM, Tuj1, MAP2ab, NeuN and NF200 in immunocytochemical analyses. Presence of astrocytes was confirmed by expression of GFAP immuno-cytochemically. Oligodendrocytes were also observed by positive immuno-reactivities against oligodendrocyte marker O1. Results of this study demonstrate that a stepwise culture condition is developed for the derivation of neural precursor cells from human ES cells.

Transforming growth factor (TGF) family is well known to induce the chondrogenic differentiation of mesenchymal stem cells (MSC). However, the precise signal transduction pathways and underlying factors are not well known. Thus the present study aims to evaluate the possible role of C2 domain in the chondrogenic differentiation of human mesenchymal stem cells. To this end, 145 C2 domains in the adenovirus were individually transfected to hMSC, and morphological changes were examined. Among 145 C2 domains, C2 domain of protein kinase C eta (PKCη) was selected as a possible chondrogenic differentiation factor for hMSC. To confirm this possibility, we treated TGFβ3, a well known chondrogenic differentiation factor of hMSC, and examined the increased-expression of glycosaminoglycan (GAG), collagen type II (COL II) as well as PKCη using PT-PCR, immunocytochemistry and Western blot analysis. To further evaluation of C2 domain of PKCη, we examined morphological changes, expressions of GAG and COL II after transfection of PKCη -C2 domain in hMSC. Overexpression of PKCη-C2 domain induced morphological change and increased GAG and COL II expressions. The present results demonstrate that PKCη involves in the TGF-β3-induced chondrogenic differentiation of hMSC, and C2 domain of PKCη has important role in this process.

Blast severity data of 39 rice varieties at 11 sites in Korea from 1997 to 1999 were analyzed using AMMI model and pattern analysis. Genotype x Environment (G~times E) interaction sum of squares (SS) accounted for 12 % of the total SS. Eight genotype groups and seven location groups were identified based on blast reaction pattern. The data obtained from over 21 sites with 44 test varieties from 1981 to 1996 were also considered. These were compared with the 1997-1999 data using the G~times E analysis results. Majority of the variability in the Korean Rice Blast Nursery (KRBN) were attributable to variations due to genotypes. Variations of G~times E interaction were maintained though test sites were reduced from 21 to 11 sites. Broadly compatible biological discriminative varieties identified were Nagdongbyeo and Akibare while broadly incompatible biological discriminative varieties identified were Hangangchalbyeo and Seogwangbyeo. Key sites for future evaluation work could be selected from location groups. Each location group should be represented by the site with the strongest interaction pattern. Blast responses in Cheolwon, Gyehwa, Suwon, Iksan, and Icheon showed different patterns from other locations.