• Proceedings of the KIEE Conference
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• 2003.07c
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• pp.1496-1498
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• 2003

The $(Sr_{0.85}Ca_{0.15})TiO_3$(SCT) thin films were deposited on Pt-coated electrode (Pt/TiN/$SiO_2$/Si) using RF sputtering method according to the deposition condition. The optimum conditions of RF power and Ar/$O_2$ ratio were 140[W] and 80/20, respectively. Deposition rate of SCT thin films was about 18.75[${\AA}/min$] at the optimum condition. The capacitance characteristics had a stable value within ${\pm}4[%]$. The drastic decrease of dielectric constant and increase of dielectric loss in SCT thin films were observed above 200[kHz].

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2006.04a
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• pp.76-77
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• 2006

유기발광소자의 주파수 응답 특성은 계면에서의 특성을 파악하는데 유요한 도구이다. 온 연구는 유기발광소자의 재료로 널리 알려진 $Alq_3$를 이용하여 소자를 제작한 후, 주파수 응답 특성을 이용하여 $Alq_3$의 등가회로를 해석하였다. 또 온도에 따른 용량성분을 분석하여 $Alq_3$에 인가된 전압에 따라 용량성분의 변화를 살펴보았다. 용량성분의 변화는 낮은 주파수 영역에서는 나타나지 않다가, 높은 주파수 영역에서 온도에 따라 미묘하게 감소하는 것을 볼 수 있다. 이는 낮은 주파수 영역에서 높은 주파수 영역으로 변화하면서 소자 내의 주된 성분이 저항성분에서 용량성분으로 변화하는 것을 의미하며 높은 주파수에서 온도에 따른 용량성분의 변화를 찾을 수 있었다.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2005.07a
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• pp.160-161
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• 2005

The $(Sr_{1-x}Ca_x)TiO_3$(SCT) thin films are deposited on Pt-coated electrode (Pt/TiN/$SiO_2$/Si) using RF sputtering method with substitutional contents of Ca. The optimum conditions of RF power and $Ar/O_2$ ratio were 140[W] and 80/20, respectively. Deposition rate of SCT thin film was about 18.75$[{\AA}/min]$. The dielectric constant was increased with increasing the substitutional contents of Ca, while it was decreased if the substitutional contents of Ca exceeded over 15[mol%]. All SCT thin films used in this study show the phenomena of dielectric relaxation with the increase of frequency, and the relaxation frequency is observed above 200[kHz].

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2006.06a
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• pp.475-476
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• 2006

과학문명의 발전으로 인간은 점차 보다 윤택한 싫을 영위하기 위해 노력하고 있다. 하지만 지구의 유한한 자원, 특히 화석연료만으로는 폭발적으로 늘어가는 에너지의 소비는 인류의 안락함을 보장해 줄 수 없게 되었다. 이에 따라 인간의 삶에 비한다면 무한한 태양에너지를 효율적으로 활용하는 것은 무엇보다 중요한 일이라 할 수 있다. 그러나 현재 활용되고 있는 무기 태양전지는 30%에 못 미치는 에너지 변환 효율은 아직 미래의 에너지로 활용하기 위해서 많은 연구와 개발이 필요한 분야이다. 또한 무기재료를 이용한 광기전소자는 비싼 가격으로 인하여 대중적으로 이용하기에는 어려움이 뒤따르고 있다. 하지만 유기재료를 소재로 이용한 광기전소자는 상대적으로 저렴한 가격과 유연한 소자의 제작에 유리한 점 때문에 많은 연구자들의 관심을 끌고 있다. 본 연구에서는 광기전소자의 개발에 널리 활용되는 ZnPc를 이용하여 주파수 응답 특성을 살펴봄으로써 재료가 가지고 있는 전기적인 특성을 살펴보았다.

• Childhood Kidney Diseases
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• v.25 no.2
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• pp.128-132
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• 2021

Morning glory syndrome (MGS) is a rare congenital optic disc anomaly with a characteristic fundal finding with severe visual impairment. It may occur in association with various systemic manifestations, even though most of the reported cases were isolated. A 6-year-old male visited the nephrology clinic with a history of microscopic hematuria and at the age of 12 years, he was diagnosed thin glomerular basement membrane nephropathy by kidney biopsy. After the following years, the patient had progressive deterioration of visual acuity, and diagnosed as MGS. Whole Exome Sequencing of this patient and his mother revealed heterozygous COL4A4 mutations [c.81_86del (p.Ile29_Leu30del)]. It is more reasonable to consider MGS seen in this patient as a coincidental finding of autosomal dominant Alport syndrome. To our knowledge, this case represents the first case report of autosomal dominant Alport syndrome associated with MGS.

• Korean journal of applied entomology
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• v.26 no.4 s.73
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• pp.195-201
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• 1987

Insects and nematodes associated with crops growing in plastic film houses were surveyed throughout the southern part of Korea at Jinju, Jiphyeon, Geumsan, Hapcheon, Changyeong, Namji, Milyang, Kimhae, Busan, Sooncheon and Gwangyang from December of 1984 to December of 1985. The phytonematodes representing six families, nine genera and nine species, and the insects representing four orders, seventeen families, twenty-three genera and twenty-four species were identified. The mite also caused problem on the leaves of strawberry and watermelon. Of these Meloidogyne incognita and Aphis gossyphii were most important ones. Aphelenchoides fragariae and M. hapla, however dominant nematodes on strawberry. M. incognita was always detected from pepper plants which were heavily infected with Phytophthora capsici. Tomato roots were readily infected with root-knot nematodes in non-sterilized upland surface soil. However, tomato were growing-vigorouly free from nematode damage in the upland surface soil treated by nematicide or in the paddy soil. A few galls were developed even in the upland subsoil at 60cm below surface. Soil salinity affected profoundly the host-root-knot nematode interaction: the numerous galls were developed on the tomato roots at EC $1mS/cm^2$ followed by 4mS and 2mS, but few galls were at 6mS.

• Development and Reproduction
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• v.17 no.4
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• pp.299-309
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• 2013

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 ($PKC{\eta}$) was selected as a possible chondrogenic differentiation factor for hMSC. To confirm this possibility, we treated $TGF{\beta}3$, a well known chondrogenic differentiation factor of hMSC, and examined the increased-expression of glycosaminoglycan (GAG), collagen type II (COL II) as well as $PKC{\eta}$ using PT-PCR, immunocytochemistry and Western blot analysis. To further evaluation of C2 domain of $PKC{\eta}$, we examined morphological changes, expressions of GAG and COL II after transfection of $PKC{\eta}$-C2 domain in hMSC. Overexpression of $PKC{\eta}$-C2 domain induced morphological change and increased GAG and COL II expressions. The present results demonstrate that $PKC{\eta}$ involves in the TGF-${\beta}3$-induced chondrogenic differentiation of hMSC, and C2 domain of $PKC{\eta}$ has important role in this process.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.47 no.5
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• pp.361-367
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• 2002

In order to determine the optimum harvest time for the seed production of inbreds and hybrids in silage corn, the ears of sib-pollinated 'KS5', 'KS7rhm', and 'Ga209' and cross-pollinated 'KS5' $\times$ 'KS6' (Suwon19), 'KS7 rhm' $\times$ 'KSl17' (Suwonok), and 'Ga209' $\times$ 'DB544'(Kwanganok) were harvested at the one-week intervals from 4 to 10 weeks after silking. The optimum harvest time for the seed production for 'KS5', 'KS5' $\times$ 'KS6', 'KS7 rhm', and 'KS7rhm' $\times$ 'KS117' was 7 weeks after silking considering both emergence rate and plumule growth in cold test. Although earlier harvested seeds showed similar germination rate as the seeds harvested at the optimum time at $25^{\circ}C$, their emergence rate were lower in cold test. Seed weight and $\alpha$-amylase activity of earlier harvested seeds were lower compared to those of seeds harvested at the optimum time, while leakage of total sugars and electrolytes were higher. However, the later harvested seeds showed lower germination rates at $25^{\circ}C$ and emergence rates in cold test probably due to the lower $\alpha$-amylase activity although they showed increased seed weight and reduced leakage of total sugars and electrolytes. In contrast, the emergence rate of 'Ga209' and 'Ga209' $\times$ 'DB544' in cold test increased up to 10 weeks after silking probably due to the increased seed weight and $\alpha$-amylase activity and reduced sugar and electrolyte leakages during the germination. The cross-pollinated F$_1$ hybrid seeds showed higher germination and emergence rates at $25^{\circ}C$ and in cold test, and higher plumule growth and $\alpha$-amylase activity compared to those of sib-pollinated inbreds.

• Journal of Embryo Transfer
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• v.15 no.3
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• pp.247-253
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• 2000

This study was undertaken to optimize enucleation and reconstitution methods for the production of cloned mice by somatic cell nuclear transfer Outbred ICR mouse oocytes at the metapahse- II stage were retrieved from female mice superovulated by PMSG and hCG. In Experiment 1, oocytes were enucleated in medium supplemented with cytochalasin B (CCB) of 3 levels (0, 7.5 or 15 $\mu\textrm{g}$/mL), and higher rate of encleation was obtained at 7.5 and 15 $\mu\textrm{g}$/mL than at $\mu\textrm{g}$/mL. In Experiment 2, oocytes enucleated in 7.5 $\mu\textrm{g}$/mL CCB-containing medium were reconstituted with different types of somatic cell by following methods; 1) cumulus cells by direct cell injection, 2) cumulus cells by electric fusion (1.25 kV/cm, 2 pulses for each 70 $mutextrm{s}$) or 3) STO cells by the electrofusion. Electrofusion of STO cells with enucleated oocytes yielded the greatest (P<0.05) rate of reconstitution without lysis (76%) than any other combinations. Although significant decrease in the rate of somatic cell introduction was found, the electrofusion of cumulus cells yielded better rate of reconstitution than direct injection (0 vs. 18%). In Experiment 3, the duration of electric stimulation for the fusion was changed to either 50 $mutextrm{s}$ or 90 $mutextrm{s}$, but no significant improvement of reconstitution efficacy was obtained. In conclusion, this study showed that ICR mouse oocytes could be used for the production of reconstituted oocytes and a fusion method of 1.25 KV/cm with 2 pulses using 570 cell was the optimal.

• Korean Journal of Microbiology
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• v.44 no.2
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• pp.93-97
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• 2008

RraA is a recently discovered protein inhibitor that regulates the enzymatic activity of RNase E, which plays a major role in the decay and processing of RNAs in Escherichia coli. It has also been shown to regulate the activity of RNase ES, a functional Streptomyces coelicolor ortholog of RNase E, which has 36% identity to the amino-terminal region of RNase E. There are two open reading frames in S. coelicolor genome that can potentially encode proteins having more than 35.4% similarity to the amino acid sequence of RraA. DNA fragment encoding one of these RraA orthologs, designated as RraAS2 here, was amplified and cloned in to E. coli vector to test whether it has ability to regulate RNase E activity in E. coli cells. Co-expression of RraAS2 partially rescued E. coli cells over-producing RNase E from growth arrest, although not as efficiently as RraA, induced by the increased ribonucleolytic activity in the cells. The copy number of ColEl-type plasmid in these cells was also decreased by 14% compared to that in cells over-producing RNase E only, indicating the ability of RraAS2 to inhibit RNase E action on RNA I. We observed that the expression level of RraAS2 was lower than that of RraA by 4.2 folds under the same culture condition, suggesting that because of inefficient expression of RraAS2 in E. coli cells, co-expression of RraAS2 was not efficiently able to inhibit RNase E activity to the level for proper processing and decay of all RNA species that is required to restore normal cellular growth to the cells over-producing RNase E.