• 천문학회보
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• 제37권2호
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• pp.117.2-117.2
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• 2012

It is generally accepted that sudden compressions of the magnetosphere cause electromagnetic ion cyclotron (EMIC) wave growth by increasing the proton temperature anisotropy. These compression-associated EMIC waves are expected to be on higher latitudes (i.e., higher-L regions close to the magnetopause). In this study we examine Pc1 pulsations, which are believed to be generated by the EMIC instability, observed at subauroral latitude near the nominal plasmapause when the magnetosphere is suddenly compressed by solar wind dynamic pressure variations, using induction magnetometer data obtained from Athabasca, Canada (geomagnetic latitude = 61.7 N, L ~ 4.5). We identified 9 compression-associated Pc1 waves with frequencies of ~0.5-2.0 Hz. The wave activity appears in the horizontal H (positive north) and D (positive eastward) components. All of events show low coherence between H and D components. This indicates that the Pc1 pulsations in H and D oscillate with a different frequency. Thus, we cannot determine the polarization state of the waves. We will discuss the occurrence location of compression-associated Pc1 pulsations, their spectral structure, and wave properties.

• 자원리싸이클링
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• 제14권6호
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• pp.10-15
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• 2005

본 연구는 Karr column을 이용한 희토류원소의 분리에 대한 연구로서, 유량, 수상의 초기 pH, 유기상인 PC88A비누화도, 교반속도 등의 변수에 따른 Sm/ND이성분계의 분리특성을 조사하였다. 수상과 유기상의 유량이 16.5ml/min(체류시간 10분)에서 수상의 초기 pH가 높아짐에 따라 Sm/Nd의 추출율 및 분리계수가 증가하였으며, 비누화의 영향으로 반응 후 수상의 평형 pH가 약 1.5정도로 유지되었다 또한 PC88A 비누화도가 증가함에 따라 추출율 및 분리계수가 증가하였으며 적정 비누화도는 $40\%$였다. 그리고 교반 모터의 회전수 증가에 의해 추출율 및 분리계수가 크게 증가하는 결과를 보였다. 체류시간 10분, 초기 pH 1, PC88A비누화도 $40\%$,교반속도 120rpm에서 Nd $19.6\%$, Sm $72.5\%$가 추출되었다.

• 한국재료학회:학술대회논문집
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• 한국재료학회 2006년도 춘계학술발표대회 및 제10회 신소재 심포지엄 논문개요집
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• pp.26.1-26.1
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• 2006

• 한국재료학회:학술대회논문집
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• 한국재료학회 2006년도 춘계학술발표대회 및 제10회 신소재 심포지엄 논문개요집
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• pp.33.2-33.2
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• 2006

• Biomolecules & Therapeutics
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• 제25권2호
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• pp.177-185
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• 2017

Auranofin has been developed as antirheumatic drugs, which is currently under clinical development for the treatment of chronic lymphocytic leukemia. Previous report showed that auranofin induced apoptosis by enhancement of annexin A5 expression in PC-3 cells. To understand the role of annexin A5 in auranofin-mediated apoptosis, we performed microarray data analysis to study annexin A5-controlled gene expression in annexin A5 knockdown PC-3 cells. Of differentially expressed genes, plasminogen activator inhibitor (PAI)-2 was increased by annexin A5 siRNA confirmed by qRT-PCR and western blot. Treatment with auranofin decreased PAI-2 and increased annexin A5 expression as well as promoting apoptosis. Furthermore, auranofin-induced apoptosis was recovered by annexin A5 siRNA but it was promoted by PAI-2 siRNA. Interestingly, knockdown of annexin A5 rescued PAI-2 expression suppressed by auranofin. Taken together, our study suggests that induction of annexin A5 by auranofin may enhance apoptosis through suppression of PAI-2 expression in PC-3 cells.

• 한국식품영양과학회지
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• 제44권5호
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• pp.761-766
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• 2015

아밀로그램 특성은 대조군과 비교하여 단백질가수분해효소의 첨가량이 증가할수록 최고점도는 유의적으로 증가하였으며, 냉각 후 점도 역시 $850.2{\pm}10.03{\sim}830.4{\pm}8.88B.U.$로 첨가량이 증가할수록 유의적으로 감소하였다. 비중과 pH 및 굽기 손실률은 대조군과 비교하여 유의적 차이는 없었으나 높이는 대조군이 $4.24{\pm}0.18cm$, 단백질가수분해효소 첨가구가 $4.84{\pm}0.09{\sim}5.06{\pm}0.11cm$ 정도로 대조군과 비교하여 유의적으로 증가하였다. 비용적은 대조군 $3.53{\pm}0.06cc/g$과 비교하여 $3.66{\pm}0.13{\sim}4.21{\pm}0.02cc/g$으로 유의적으로 높게 나타났으며, 이러한 현상은 계란단백질의 폴리펩타이드 사슬을 가수분해하여 반죽이 연화되고 윤활성이 증가하여 최종제품의 부피, 기공, 색상 및 품질이 향상되었다는 연구 결과(16)와 유사하였으며 crust의 적색도는 대조군과 비교하여 유의적으로 증가하였다. 경도는 대조군의 0일차가 $323.96{\pm}30.84$였고, 실험군은 $324.36{\pm}28.53{\sim}280.08{\pm}26.66$으로 감소하였으나 유의적 차이는 없었다. 2일차의 경도는 PC-2가 $420.64{\pm}43.46$, PC-3이 $393.79{\pm}34.64$, PC-4가 $373.35{\pm}30.82$로 대조군의 $456.01{\pm}37.64$보다 유의적으로 감소하였다(P<0.05). 관능검사는 껍질색과 내부 색상이 대조군과 비교하여 유의적 차이는 없었으나 맛, 향, 조직감, 촉촉한 정도, 식감에서는 유의적으로 높은 점수를 얻었다(P<0.05). 이상의 결과로 스펀지케이크에 단백질가수분해효소를 첨가하면 부피, 높이, 비용적에 영향을 주어 부피가 증가하고 품질 개선에 효과적인 것을 확인하였다.

• 컴퓨터교육학회논문지
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• 제5권3호
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• pp.27-35
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• 2002

대학의 정보화 예산을 체계적으로 편성하기 위하여 대학의 전산자원중에서 중요한 PC와 소프트웨어 관리 및 활용에 대한 모델과 네트워크의 적정 속도에 대한 모델을 제안한다. 보유 PC의 활용도 증진을 위한 대책, PC 유지 보수의 문제점과 대책, PC의 효율적인 확충과 교체 방안, 소프트웨어 구입과 효율적인 활용방안을 제안한다. 또한 정보 시스템의 마스터플랜 수립의 핵심부분인 네트워크 환경과 관리를 위한 적정한 모델을 제안한다. 네트워크를 내부망과 외부망으로 구분하여 네프워크의 적정 속도를 산정하기 위한 수석모델을 제안한다. 그리고 대학이라는 조직의 특성을 살리고 보안을 유지할 수 있는 방안을 제안한다.

• Journal of Astronomy and Space Sciences
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• 제37권1호
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• pp.19-27
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• 2020

Pc1 pulsations are important to consider for the interpretation of wave-particle interactions in the Earth's magnetosphere. In fact, the wave properties of these pulsations change dynamically when they propagate from the source region in the space to the ground. A detailed study of the wave features can help understanding their time evolution mechanisms. In this study, we statistically analyzed Pc1 pulsations observed by a Bohyunsan (BOH) magneto-impedance (MI) sensor located in Korea (L = 1.3) for ~one solar cycle (November 2009-August 2018). In particular, we investigated the temporal occurrence ratio of Pc1 pulsations (considering seasonal, diurnal, and annual variations in the solar cycle), their wave properties (e.g., duration, peak frequency, and bandwidth), and their relationship with geomagnetic activities by considering the Kp and Dst indices in correspondence of the Pc1 pulsation events. We found that the Pc1 waves frequently occurred in March in the dawn (1-3 magnetic local time (MLT)) sector, during the declining phase of the solar cycle. They generally continued for 2-5 minutes, reaching a peak frequency of ~0.9 Hz. Finally, most of the pulsations have strong dependence on the geomagnetic storm and observed during the early recovery phase of the geomagnetic storm.

• BMB Reports
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• 제31권5호
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• pp.468-474
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• 1998

Membrane depolarization in PC12 cells induces calcium influx via an L-type voltage-sensitive calcium channel (L-VSCC) and increases intracellular free calcium, which leads to tyrosine phosphorylation of epidermal growth factor (EGF) receptor and the associated adaptor protein, She. This activated EGF receptor complex then can activate mitogen-activated protein (MAP) kinase, as in nerve growth factor (NGF) receptor activation. In the present study, we investigated the role of EGF receptor in the signaling pathway initiated by membrane depolarization of PC12 cells. Prolonged membrane depolarization induced phosphorylation of extracellular signal-regulated kinase (ERK) within 1 min in undifferentiated PC12 cells. Pretreatment of PC12 cells with the calcium chelator EGTA abolished depolarization-stimulated ERK phosphorylation, but NGF-induced phosphorylation of ERK was not affected. The chronic treatment of phorbol ester, which down-regulated the activity of protein kinase C (PKC), did not affect the phosphorylation of ERK upon depolarization. In the presence of an inhibitor of EGF receptor, neither depolarization nor calcium ionophore increased the level of ERK phosphorylation. These data imply that the EGF receptor is functionally necessary to activate ERK and neurite outgrowth in response to the prolonged depolarization in PC12 cells, and also that PKC is apparently not involved in this signaling pathway.

• 한국식물병리학회지
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• 제13권1호
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• pp.46-56
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• 1997

Based on the principal component analysis (PCA) of Richards' parameter estimates, ginseng field soils were grouped as the principal component 1 (PC1) and the principal component 2 (PC2). The microflora and physico-chemical characteristics of each soil group were compared to elucidate soil environmental factors affecting the disease development of root rot of ginseng seedling. Among 3 soil groups by PC1, there were differences in the populations of total fungi (TF) and Cylindrocarpon plus Fusarium (C+F), and the population ratio of Cylindrocarpon plus Fusarium to total fungi or total bacteria (C+F/TF, C+F/TB) in rhizoplane of ginseng seedlings, the population of total actinomycetes (TA) and the population ratio of total Fusarium to total actinomycetes (Fus/TA) in soil, and soil chemical properties (EC, NO3-N, K, Mn, ect.). Among 4 soil groups by PC2, there were differences in TF, C+F, TB, C+F/TF and C+F/TB in the rhizoplane, Trichoderma plus Gliocladium (T+G) in soil, and P2O5 content in soil. Especially, EC, NO3-N, K, K/Mg and Mn were positively correlated to PC1, and TA was negatively to PC1; however, TF, C+F, TB, C+F/TF and C+F/TB in the rhizoplane were significantly correlated to PC2 positively. On the other hand, microbes in the rhizoplane were not significantly correlated to the stand-missing rate (SMR), although TA and Fe/Mn were negatively correlated, and pH and Ca were positively correlated to SMR.