• The Journal of Korean Institute of Communications and Information Sciences
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• v.18 no.8
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• pp.1102-1107
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• 1993

Microwave dielectric properties of CaTiO3 and CaTiO3-TiO2 ceramics for the composition range between 40 and 50 mol% CaO in CaO-TiO2 binary system were investigated. CaTiO3 ceramics with50 mol% CaO showed the dielectric constant (e,) of 178, the temperature coefficient of resonant frequency(c,) of+1000 ppm/'c and the qualify factor Q of 2760 (f0=2.7 GHz ). Dielectric constant and temperature coefficient of resonant frequency of ceramics with dual phases of CaTiO3 and TiO2 decreased gradually from those of CaTiO3 as the CaO content decreased. Q value and density were found to have minimum at the composition of 47 mol% CaO. The degradation of Q value and density in dual phase ceramics seems to be caused by the large pores at grain boundaries and/or within grains remained after rapid growth of CaTiO3 grains as TiO2 Phase decreased.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.17 no.8
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• pp.835-839
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• 2004

The surge characteristics of ZnO varistors consisting of $ZnO-{Pr}_6{O}_11-CoO-{Cr}_2{O}_3-{Er}_2{O}_3$ceramics were investigated at various sintering temperatures. As sintering temperature raises, the varistor voltage was decreased from 341.2 to 223.1 V/mm, the nonlinear exponent was decreased from 64,9 to 44.1. On the other hand, the leakage current exhibited a minimum(0.64 $\mu$A) at 134$0^{\circ}C$, The clamping capability was slightly deteriorated with increasing sintering temperature. On the whole, the ZPCCE-based ZnO varistors exhibited good clamping voltage characteristics as exhibiting the clamping voltage ratio of 1.85 ∼ 1.92 approximately at surge current of 100 A.

• Journal of Korean Library and Information Science Society
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• v.3
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• pp.79-88
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• 1976

In Ecorea Lrynasty, the authority all officers a compulsary obligatic.~ to learn the Nyo-I~.'z~\ulcorneruzngd er the custody of a super1 iscr o; Letters wino -1 a\ulcorner the ~ejponsible officer to train ci~ril senants. The Nyo-Kjli ilg was possible to interpret the pious love of ci I illans to the~re lders as a mutual ethics between the parental ber~ec;~lc nce and the filial piety of inferiors which n-as far superior to the traditional cthic; that was laid on an firm obligation of inieri~rs to tEei:- elders. The filial piety as a lovc for elders mean2 a mutual harrn~n:a~n d show\ulcorner a berieiolent conduct as an influence of a political morality. Thc heaer-o!erLt conduct was developed as a political morality of Confucius originated from the filial piety of Confucius based on a moral policj . Such a kenerolent conduct is to become a main spring to effect a mutual tie betn-een the king and his people as a national system of the Confucian theory. In i*

• Journal of Life Science
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• v.25 no.4
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• pp.473-480
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• 2015

The endoplasmic reticulum (ER) in the eukaryotic cells is the first compartment in the secretory pathway. Almost secretory proteins and membrane proteins are secreted through the ER, in which post-translational modifications occur via diverse signals from the ER lumen to the cytoplasm and nucleus. Only then are correctly-folded proteins secreted to the outside cells. Unfolded proteins that accumulate in the ER cause a kind of intracellular stress, ER stress, and activate an unfolded protein response (UPR) system. The 3 major transducers of the UPR are inositol requiring 1 (IRE1), PKR-like ER kinase (PERK) and activating transcription factor 6 (ATF6), all of which are ER transmembrane proteins. Recently, novel types of a new ATF6 family have been identified. Those commonly have an ER-transmembrane domain, a transcription-activation domain and a basic leucine zipper (bZIP) domain―Luman, OASIS, BBF2H7, CREBH and CREB4. Each factor functions by regulating the UPR in specific organs and tissues. Although the detailed molecular mechanisms of OASIS family members are unknown, in this study we comprehensively introduce these molecular signals.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2004.07b
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• pp.679-683
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• 2004

[ $BaO-Sm_2O_3-4TiO_2$ ] 세라믹을 LTCC용 재료로 사용하기 위해 $B_2O_3$와 CuO를 소결조제로 첨가하여 소결온도를 낮추었다. 10.0 mol%의 $B_2O_3$만을 첨가하였을 경우 $1000^{\circ}C$에서 2시간 소결시 er=72.23, Qf=4,050GHz, ${\tau}f=-0.574ppm/^{\circ}C$의 우수한 유전 특성값을 얻을 수 있었지만, $960^{\circ}C$이하에서는 소결이 잘 이루어지지 않았다. $B_2O_3$와 CuO를 동시에 소결조제로 첨가하였을 경우에는 $900^{\circ}C$에서 2시간 소결시 10.0 mol% $B_2O_3$, 15.0 mol% CuO의 첨가조성에서 ${\varepsilon}r$=70.09, Qf=4,728GHz의 우수한 유전특성을 보여 고유전율을 가진 저온 동시 소결용 재료로서의 가능성을 보여주었다. 이처럼 BaO-$Sm_2O_3-4TiO_2$ 세라믹의 소결온도를 낮출 수 있었던 요인은 소결온도보다 용융점이 낮은 2차상들이 액상을 형성하여 액상소결이 진행되었기 때문이며 이때 소결에 기여한 이차상들은 결정화되지 못하고 비정질 상태로 남아있는 것으로 추정된다.

• Proceedings of the KIEE Conference
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• 2004.07c
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• pp.1706-1708
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• 2004

This paper reports the stability against surge of ZnO-$Pr_6O_{11}$-CoO-$Cr_2O_3-Er_2O_3$-based varistors sintered at different sintering temperatures. As sintering temperature increases, the varistor voltage decreased in the range of 412${\sim}$266 V and the nonlinear exponent decreased in the range of 61${\sim}$50. Meanwhile, the stability against surge with surge peak current of 100 $A/cm^2(8{\times}20{\mu}s)$ exhibited to be good on the whole.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.4
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• pp.2447-2451
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• 2013

Objective: To study changes of tumor associated carbohydrate antigen (TACAs) expression and mRNA levels for tumor associated glycosyltransferases, and assess subcellular localizations of N-acetyl galactosyltransferases (GalNAc-Ts) in the K562 leukemia cell line after imatinib treatment. Methods: RT-PCR was performed to analyze the expression of glycosyltransferases which synthesize O-glycan in tumor-associated carbohydrate antigens (TCTAs). The expression of Tn antigen, T antigen and sialyl T antigen on K562 cell membranes was measured by flow cytometry after treatment with different concentrations of imatinib. Co-localization of GalNAc-Ts and ER (endoplasmic reticulum) was determined by confocal laser scanning microcopy. Results: Transcript expression levels of several glycosyltransferases related to TCTAs were decreased after imatinib ($0-0.3{\mu}M$) treatment. Expression of Tn antigen and T antigen was increased while that of sialyl T antigen was decreased. Co-localization of GalNAc-Ts and ER was reduced by $0.2{\mu}M$ of imatinib. Conclusion: Imatinib inhibited the expression of O-glycan related TACAs and several related glycosyltransferases, while decreasing the co-localization of GalNAc-Ts and ER and normalizing O-glycosylation in the K562 human leukemia cell.

• Journal of the Korean Ceramic Society
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• v.35 no.4
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• pp.364-370
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• 1998

Boron-phoshor-silicate glass was fabricated on Si substrates by FHD(Flame Hydrolysis Deposition) The microstructrue of silica soot deposited at various conditon such as composition and substrate temperature was analysed by SEM. After consolidation the refractive index and composition of the silica layer were in-vestigated. For refractive index control B, P and Ge were used as additive elements while B and Ge oxides are easily mixed into $SiO_2$, P oxide($B_2O_3$) doping is difficult because of the volatile property due to low melt-ing point. Boron-phosphorous-silicate glass (BPSG) layer were fabricated using bertical torch and optimized flame temperature substrate temperature and distance of torch and substrate. P concentration of BPSG lay-er measured 3.3 Wt% and the consolidation temperature was lower than $1180^{\circ}C$. The measured refractive index of BPSG silica layer in $1.55\;\mu\textrm{m}$ wavelength was $1.4480{\pm}1{\times}10^{-1}$ and the thickness was $22{\pm}1\;\mu\textrm{m}$.

• Journal of Society of Preventive Korean Medicine
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• v.5 no.1
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• pp.116-133
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• 2001

Antifibrotic drugs could be delayed or inhibited massive collagen deposition in liver tissue or inhibited collagen synthesis. we investigated antifibrotic effects by several herbs(Schisnadra chinensis, Ganoderma japonicum, Sedum sarmentosum, Alisma canaliculatum, Plantago asiatica) extract with observations of collagen accumulation in liver tissue and collagen synthesis in sera. Rats were used for experimental animal that were devided 3 groups(sham control, BDL/S, BDL/S-ER). Rats were operated for inducing liver fibrosis(cirrhosis) by bile duct obstruction. Several herbs were prepared by water extraction and were applicated p. o. $3ml/day$ during 4 weeks. After observation period, rats were sacrificed and liver tissue and sera were collected. In result, the mortality of rats was 35% in BDL/S group and 20% in BDL/S-ER The color of bile juice in BDL/S-ER was bright yellow and murky yellow in BDL/S group. The significantly lower weight of liver($16.21g{\pm}5.3,\;20.58{\pm}2.4$) and spleen($1.96g{\pm}0.96,\;3.93{\pm}0.21$) were shown in BDL/S-ER than that of BDL/S(p<0.05) group. The value of collagen in liver tissue(25.7%) in BDL/S-ER was observed significantly lower than that of BDL/S group (Tab. 2). AST. ALT, ALP, t-bilirubin, BUN levels were low in BDL/S-ER as compared with those of BDL/S group, but the significance was not proven. The trichrome stained liver tissue in BDL/S-ER group was observed mild bile duct proliferation and fibrosis compared with BDL/S group. In conclusion, natural products inhibited new collagen synthesis and delayed massive collagen deposition in liver tissue, so that they have noticeable antifibrotic effects in experimental liver fibrosis(cirrhosis).

• Journal of the Korean Ceramic Society
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• v.35 no.10
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• pp.1107-1112
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• 1998

We could obtan c-axis oriented $SrBi_2$$Ta_2$$O_9$ thin films on usual Pt(111)/Ti/$SiO_2$/Si(100) substrate using a r. f. magnetron sputtering technique. According to the increase of sputtering pressure from 250 to 300 mTorr the Bi content and degree of the c-a xis preferred orientation of $SrBi_2$$Ta_2$$O_9$ thin films were increased. By controlling Bi(or $Bi_2O_3$) loss from $SrBi_2$$Ta_2$$O_9$ thin films during post annealing and by inserting $Bi_2O_3$ layer in $SrBi_2$$Ta_2$$O_9$ thin films the effect of Bi content on the c-axis oriented growth of $SrBi_2$$Ta_2$$O_9$ thin films could be investigated without the effect of sputtering pressure. The degree of the c-axis preferred orientation of $SrBi_2$$Ta_2$$O_9$ thin films was increased with increasing with increasing Bi content by control of Bi(or $Bi_2O_3$) loss of $SrBi_2$$Ta_2$$O_9$ thin films. But the c-axis oriented growth of $SrBi_2$$Ta_2$$O_9$ thin films disappeared by the inserting of $Bi_2O_3$ lay-er in $SrBi_2$$Ta_2$$O_9$ thin films.