• English Language & Literature Teaching
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• v.16 no.3
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• pp.365-395
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• 2010

This study explores the effect of extensive reading(ER) implemented in middle and high schools in Korean EFL context. Two middle school English teachers and two high school English teachers participated in implementing ER in their classes. Six middle school classes of 239 students and seven high school classes of 268 students participated in ER program guided by the above four teachers. To implement ER, participating teachers had continuously been guided by the researcher about the theoretic reasoning of ER and practical methods for efficient ER in class. The study lasted for two semesters and the teachers and students were surveyed and interviewed during and after the classes. The result showed pretty positive improvement of students' self-confidence, interest and motivation about English through ER implemented in this study. It is hoped that this study would show the possibility of implementing ER in Korean EFL secondary school context and a model for ER and cooperation between university researchers and in-service English teachers.

• The Korean Journal of Rheology
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• v.10 no.1
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• pp.31-37
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• 1998

전기장이 인가되고 있는 유로를 유동하는 전기유변유체의 기본성질을 파악하기 위 한 실험 및 해석적 연구를 수행하여 빙햄유체로서의 유효성에 대해 알아보고 전기장과 유로 면 형상 및 진동유동으로 인한 영향에 대해 조사함으로써 ER밸브 및 ER대퍼로의 응용과 관련한 감쇄력 제어에 대해 검토하였다. 첫 번째 실험은 ER밸브의 높이가 2mm인 적극면이 평탄한것과 요철로 된 것을 사용하여 압력손실을 압력변환기로 측정함으로써 전기장 및 유 로형상에 대한 영향을 알아보았다. 압력손실 및 전단응력이 전기자세기와 함수관계를 가짐 을 알수 있었고 전기장세기와 유속의 변화시 손실계수에 의한 ER효과의 상이함이 확인되었 으며 레이놀즈수가 커지면 항복전단응력의 영향은 나타나지 않았다. 두 번째 실험은 실린더 를 정현파로 진동시켜 ER밸브에서 감쇠력제어가 가능한가를 알아보고 빙햄유체모델로 설계 된 ER댐퍼의 모델과 비교하였다. ER배르와 ER댐퍼의 수학적 모델을 시뮬레이션한 결과는 약간 벗어남이 보이기는 하나 실험결과와 일치하요 있다. 이것은 ER유체를 단순히 빙행유 체로 취급할수없으나 거시적으로는 빙햄유체로 취급할수 있음을 시사한다.

• Journal of Nutrition and Health
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• v.52 no.2
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• pp.176-184
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• 2019

Purpose: Protein overloading in the endoplasmic reticulum (ER) leads to endoplasmic reticulum stress, which exacerbates various disease conditions. Emodin, an anthraquinone compound, is known to have several health benefits. The effect of emodin against palmitic acid (PA) - induced ER stress in HepG2 cells was investigated. Methods: HepG2 cells were treated with varying concentrations of palmitic acid to determine the working concentration that induced ER stress. ER stress associated genes such as ATF4, XBP1s, CHOP and GRP78 were checked using RT- PCR. In addition, the expression levels of unfolded protein response (UPR) associated proteins such as $IRE1{\alpha}$, $eIF2{\alpha}$ and CHOP were checked using immunoblotting to confirm the induction of ER stress. The effect of emodin on ER stress was analyzed by treating HepG2 cells with $750{\mu}M$ palmitic acid and varying concentrations of emodin, then analyzing the expression of UPR associated genes. Results: It was evident from the mRNA and protein expression results that palmitic acid significantly increased the expression of UPR associated genes and thereby induced ER stress. Subsequent treatment with emodin reduced the mRNA expression of ATF4, GRP78, and XBP1s. Furthermore, the protein levels of $p-IRE1{\alpha}$, $p-eIF2{\alpha}$ and CHOP were also reduced by the treatment of emodin. Analysis of sirtuin mRNA expression showed that emodin increased the levels of SIRT4 and SIRT7, indicating a possible role in decreasing the expression of UPR-related genes. Conclusion: Altogether, the results suggest that emodin could exert a protective effect against fatty acid-induced ER stress and could be an agent for the management of various ER stress related diseases.

• Journal of Mechanical Science and Technology
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• v.18 no.8
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• pp.1479-1489
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• 2004

The effect of fluctuation of Equivalence Ratio (ER) in a turbulent reactive field has been studied in order to check the global combustion characteristics induced by the local fluctuation. When the flow is premixed on a large scale, closer examination on a small scale reveals that local fluctuations of ER exist in an imperfectly premixed mixture, and that these fluctuations must be considered to correctly estimate the mean reaction rate. The fluctuation effect is analyzed with DNS by considering the joint PDF of reactive scalar and ER, followed by modeling study where an extension of stochastic mixing models accounting for the ER fluctuation is reviewed and tested. It was found that models prediction capability as well as its potential is in favor to this case accounting the local ER fluctuation. However, the effect of local fluctuation did not show any notable changes on the mean global characteristics of combustion when statistical independence between the reactive scalar and ER field is imposed, though it greatly influenced the joint PDF distribution. The importance of taking into account the statistical dependency between ER and combustible at the initial phase is demonstrated by testing the modeled reaction rate.

• KSTLE International Journal
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• v.8 no.2
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• pp.21-25
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• 2007

The electrorheological effect of the suspension composed of Bismark Brown chitosan succinate as the dispersed phase in silicone oil was investigated. Bismark Brown chitosan succinate suspension showed a typical ER response (Bingham flow behavior) upon application of an electric field. The shear stress for the suspension exhibited the dependence with a factor equals to 1.84 power on the electric field. The experimental results for the suspension correlated with the polarization model and Bismark Brown chitosan succinate suspension behaved as an anhydrous ER fluid. On the basis of the results, Bismark Brown chitosan succinate suspension showed the ER flow behavior upon application of the electric field due to the polarizability of the branched amide and amine polar groups of the Bismark brown chitosan succinate particles.

• YAKHAK HOEJI
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• v.54 no.2
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• pp.102-105
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• 2010

Our previous results showed that hypoxia inducible factor-1 (HIF-1) activated estrogen receptor (ER) in the absence of ligand. In this study, we have studied the effect ER overexpression on the activation of HIF-1. ER overexpression induced transcription activation of hypoxia response element driven luciferase and vascular endothelial growth factor. As a negative control, the effect of ER on androgen receptor response element was used. Our result indicate that the two ER$\alpha$ and HIF-1 signaling pathways shares part of the activation pathway.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2003.11a
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• pp.638-642
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• 2003

This paper presents a parameter design of an Electrorheological(ER) panel for noise reduction using Taguchi method. Taguchi method is a robust design method that determines control parameters in the presence of noise effect. Host structure thickness, spacer thickness, base oil viscosity and the weight ratio of ER particles are chosen for the control factors. A test setup in an SAE J1400 facility is used to analyze the sound transmission loss. The sensitivity of each factor with signal-to-noise(S/N) ratio and analysis of variance are investigated. The analysis results show that the weight ratio of ER particle and base oil viscosity of the ER fluid mostly affects the noise reduction in the presence of electric field. Based on the Taguchi method, an optimal configuration was designed and comparison is made with experimental result fer the verification.

• The Korean Journal of Physiology and Pharmacology
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• v.22 no.5
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• pp.567-575
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• 2018

Acute kidney injury (AKI), which is defined as a rapid decline of renal function, becomes common and recently recognized to be closely intertwined with chronic kidney diseases. Current treatment for AKI is largely supportive, and endoplasmic reticulum (ER) stress has emerged as a novel mediator of AKI. Since carbon monoxide attenuates ER stress, the objective of the present study aimed to determine the protective effect of carbon monoxide releasing molecule-2 (CORM2) on AKI associated with ER stress. Kidney injury was induced after LPS (15 mg/kg) treatment at 12 to 24 h in C57BL/6J mice. Pretreatment of CORM2 (30 mg/kg) effectively prevented LPS-induced oxidative stress and inflammation during AKI in mice. CORM2 treatment also effectively inhibited LPS-induced ER stress in AKI mice. In order to confirm effect of CO on the pathophysiological role of tubular epithelial cells in AKI, we used mProx24 cells. Pretreatment of CORM2 attenuated LPS-induced ER stress, oxidative stress, and inflammation in mProx24 cells. These data suggest that CO therapy may prevent ER stress-mediated AKI.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.20 no.4
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• pp.173-177
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• 2010

Thermal stabilizing effect of $Yb^{3+},\;Er^{3+}$ codoping into $TiO_2$ powder prepared by sol-gel method and its upconversion characteristics were analyzed. The effect of $TiO_2:Yb^{3+},\;Er^{3+}$ ions on crystallinity and phase transition was studied by X-ray diffraction (XRD). The change of band-gap energy induced from Yb and Er codoping was analyzed by UV-Vis. The band-gap energy of $TiO_2$ have been slightly narrowed by $Yb^{3+},\;Er^{3+}$ codoping, which indicated that the $Yb^{3+},\;Er^{3+}$ ions can enhance the photo-catalytic property of $TiO_2$. green and red up-conversions of $Yb^{3+}$ and $Er^{3+}$ co-doped $Y_2O_3:Yb^{3+},\;Er^{3+}$ phosphor were analyzed by PL equipped with 980 nm laser.

• Journal of Aquaculture
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• v.15 no.1
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• pp.31-37
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• 2002

Effect of 2,4-Dichlorophenoxy acetic acid (2,4-D) on vitellogenin (VTG) production and estrogen ($E_2$)-estrogen receptor (ER) binding affinity were examined in primary hepatocyte cultures of rainbow trout, Oncorhynchus mykiss. Hepatocytes were pre-cultured for 2 days; subsequently, $E_2$( 2$\times$$10^{-6}$/ M) and 2,4-D ($10^{-9}~10^{-6}/M$) were simultaneously added to the incubation medium. They were cultured for more than 5 days. VTG and $E_2$-ER binding affinities were analyzed by SDS-PAGE and ELISA, respectively. 2,4-D concentration used had no appreciable effect on the morphology, viability, and DNA content of hepatocytes in culture. It had also no effect on VTG production. However, it interfered with $E_2$-ER binding affinity, which was reduced with increasing concentration of 2,4-D. The affinity was inhibited by 25 and 30% at $10^{-7}$ M and $10^{-6}$ M of 2,4-D, respectively. This result suggested that although 2,4-D had no effect on VTG production, it acted as reno-estrogenic contaminant in ER.