Calculations of AC magnetic losses from the experimental field profiles in various types of coated conductors under applied fields

Yoo, J,Lee, S,Jung, Y,Lee, J,Youm, D,Ha, H,Kim, H,Ko, R-K,Oh, S Institute of Physics 2008 Journal of physics. Conference series Vol.97 No.1

<P>We measured the field profiles, <I>H</I>(<I>x,H</I><SUB>a</SUB>) s, near the surface of coated conductors (CCs) by using the scanning Hall probe method. The samples were SmBCO-CC tape fabricated by co-evaporation method and YBCO-CC tape fabricated by PLD method. The applied fields, <I>H</I><SUB>a</SUB>s, were decreased from <I>H</I><SUB>peak</SUB>to -<I>H</I><SUB>peak</SUB> stepwise. From the values of <I>H</I>(<I>x,H</I><SUB>a</SUB>), we calculated the current profiles, <I>J</I>(<I>x,H</I><SUB>a</SUB>) s, by the inversion method. From the values of <I>J</I>(<I>x,H</I><SUB>a</SUB>) and the corresponding flux densities, we calculated the hysteretic energy losses per cycle, <I>Q</I><SUB>M</SUB>s, for various <I>H</I><SUB>peak</SUB>s. From the values of <I>Q</I><SUB>M</SUB>, we calculated the characteristic functions, <I>g</I>s, by using the relation, <I>g</I>= π<I>Q</I><SUB>M</SUB>/μ<SUB>0</SUB><I>I</I><SUP>2</SUP><SUB>c</SUB>. Here, <I>I</I><SUB>c</SUB> is the critical current. For the range of <I>H</I><SUB>peak</SUB>/<I>H</I><SUB>c</SUB>≤ 3, the <I>g</I>-values of SmBCO CC tape were larger than those of YBCO CC tape. However, for the range of <I>H</I><SUB>peak</SUB>/<I>H</I><SUB>c</SUB> ≥ 3, the <I>g</I>-values of SmBCO CC tape were smaller than those of YBCO CC tape. When <I>H</I><SUB>peak</SUB>/<I>H</I><SUB>c</SUB> = 3, both sample show almost same value of <I>g.</I>However we found qualitatively different <I>J–B</I> hysteretic curves for both samples. We also compared our <I>g</I>-values with other <I>g</I>-values, which were directly measured by energy loss experiments. Our <I>g</I>-values of YBCO CC tapes were basically similar to the Brandt's theoretical values of <I>g</I> in the most range of <I>I</I><SUB>peak</SUB> in our measurements.</P>

Effects of HA and NA glycosylation pattern changes on the transmission of avian influenza A(H7N9) virus in guinea pigs

Park, S.,Lee, I.,Kim, J.I.,Bae, J.Y.,Yoo, K.,Kim, J.,Nam, M.,Park, M.,Yun, S.H.,Cho, W.I.,Kim, Y.S.,Ko, Y.Y.,Park, M.S. Academic Press 2016 Biochemical and biophysical research communication Vol.479 No.2

Avian influenza H7N9 virus has posed a concern of potential human-to-human transmission by resulting in seasonal virus-like human infection cases. To address the issue of sustained human infection with the H7N9 virus, here we investigated the effects of hemagglutinin (HA) and neuraminidase (NA) N-linked glycosylation (NLG) patterns on influenza virus transmission in a guinea pig model. Based on the NLG signatures identified in the HA and NA genetic sequences of H7N9 viruses, we generated NLG mutant viruses using either HA or NA gene of a H7N9 virus, A/Anhui/0½013, by reverse genetics on the 2009 pandemic H1N1 virus backbone. For the H7 HA NLG mutant viruses, NLG pattern changes appeared to reduce viral transmissibility in guinea pigs. Intriguingly, however, the NLG changes in the N9 NA protein, such as a removal from residue 42 or 66 or an addition at residue 266, increased transmissibility of the mutant viruses by more than 33%, 50%, and 16%, respectively, compared with a parental N9 virus. Given the effects of HA-NA NLG changes with regard to viral transmission, we then generated the HA-NA NLG mutant viruses harboring the H7 HA of double NLG addition and the N9 NA of various NLG patterns. As seen in the HA NLG mutants above, the double NLG-added H7 HA decreased viral transmissibility. However, when the NA NLG changes occurred by a removal of residue 66 and an addition at 266 were additionally accompanied, the HA-NA NLG mutant virus recovered the transmissibility of its parental virus. These demonstrate the effects of specific HA-NA NLG changes on the H7N9 virus transmission by highlighting the importance of a HA-NA functional balance.

Wall stretch and thromboxane A2 activate NO synthase (eNOS) in pulmonary arterial smooth muscle cells via H2O2 and Akt-dependent phosphorylation

Kim, H. J.,Yoo, H. Y.,Jang, J. H.,Lin, H. Y.,Seo, E. Y.,Zhang, Y. H.,Kim, S. J. Springer Science + Business Media 2016 Pfl ugers Arch Vol.468 No.4

<P>Pulmonary arteries (PAs) have high compliance, buffering the wide ranges of blood flow. Here, we addressed a hypothesis that PA smooth muscle cells (PASMCs) express nitric oxide synthases (NOS) that might be activated by mechanical stress and vasoactive agonists. In the myograph study of endothelium-denuded rat PAs, NOS inhibition (L-NAME) induced strong contraction (96 % of 80 mM KCl-induced contraction (80K)) in the presence of 5 nM U46619 (thromboxane A(2) (TXA(2)) analogue) with relatively high basal stretch (2.94 mN, S(+)). With lower basal stretch (0.98 mN, S(-)), however, L-NAME application following U46619 (TXA(2)/L-NAME) induced weak contraction (27 % of 80K). Inhibitors of nNOS and iNOS had no such effect in S(+) PAs. In endothelium-denuded S(+) mesenteric and renal arteries, TXA(2)/L-NAME-induced contraction was only 18 and 21 % of 80K, respectively. Expression of endothelial-type NOS (eNOS) in rat PASMCs was confirmed by RT-PCR and immunohistochemistry. Even in S(-) PAs, pretreatment with H2O2 (0.1-10 mu M) effectively increased the sensitivity to TXA(2)/L-NAME (105 % of 80K). Vice versa, NADPH oxidase inhibitors, reactive oxygen species scavengers, or an Akt inhibitor (SC-66) suppressed TXA(2)/L-NAME-induced contraction in S(+) PAs. In a human PASMC line, immunoblot analysis showed the following: (1) eNOS expression, (2) Ser(1177) phosphorylation by U46619 and H2O2, and (3) Akt activation (Ser(473) phosphorylation) by U46619. In the cell-attached patch clamp study, H2O2 facilitated membrane stretch-activated cation channels in rat PASMCs. Taken together, the muscular eNOS in PAs can be activated by TXA(2) and mechanical stress via H2O2 and Akt-mediated signaling, which may counterbalance the contractile signals from TXA(2) and mechanical stimuli.</P>

DMNQ S-64 Induces Apoptosis via Caspase Activation and Cyclooxygenase-2 Inhibition in Human Nonsmall Lung Cancer Cells

LIM, E.-S.,RHEE, Y.-H.,PARK, M.-K.,SHIM, B.-S.,AHN, K.-S.,KANG, H.,YOO, H.-S.,KIM, S.-H. Wiley (Blackwell Publishing) 2007 Annals of the New York Academy of Sciences Vol.1095 No.1

<P>Shikonin has been reported to induce apoptosis and inhibit angiogenesis in vivo and in vitro. 6-(1-propoxyiminoalkyl)-5,8-dimethoxyoxy 1,4-naphtoquinone S-64 (DMNQ S-64) was synthesized as a shikonin derivative. In this article, the underlying apoptotic mechanism of DMNQ S-64 was examined. DMNQ S-64 exerted cytotoxicity against A549 lung carcinoma cells with IC(50) of 27.3 microM. Apoptotic bodies were observed in DMNQ S-64-treated A549 cells by 4'-6-diamidino-2-phenylindole (DAPI) staining assay. DMNQ S-64 also increased sub-G1 DNA portion in a concentration-dependent manner by flow cytometric analysis. Western blotting has revealed that DMNQ S-64 effectively activates the expression of caspase 8, 9, and 3, cleaves poly (ADP-ribose) polymerase, and increases the ratio of Bax/Bcl-2. Furthermore, cytochrome c was released in a concentration-dependent manner by DMNQ S-64. Similarly, DMNQ S-64 significantly increased caspase 3 activity by enzyme-linked immunosorbent assay (ELISA). It also significantly inhibited the level of prostaglandin E2 (PGE(2)) by ELISA and downregulated the expression of cyclooxygenase-2 (COX-2) in a concentration-dependent manner. Taken together, DMNQ S-64 may exhibit cytotoxicity against A549 cells via caspase activation and COX-2 inhibition.</P>

벼 육묘트레이를 이용한 어린 잎 채소 생육에 미치는 광 조절 영향

최기영 ( K. Y. Choi ),김시홍 ( S. H. Kim ),김재경 ( J. K. Kim ),유형주 ( H. J. Yoo ),김일섭 ( I. S. Kim ) 강원대학교 농업생명과학연구원(구 농업과학연구소) 2016 강원 농업생명환경연구 Vol.28 No.2

벼 육묘 트레이를 활용한 어린잎 채소 재배 가능성을 탐색하고자 재배 기간 중 차광 처리하여 다채, 청경채, 알파인배추, 청치마 상추 등 4종을 17일간 재배하였다. 차광 처리는 무차광 17일(NS), 차광 8일+무차광 9일 (S8NS9), 무차광 8일+차광 9일(NS8S9), 차광 17일(S17) 하였다. 처리에 따른 누적 광량은 NS>S8NS9>NS8S9>S17처리구 순으로 높았으나, 누적 온도는 처리에 따른 차이가 크지 않았다 차광 8일 째 어린잎채소 4종의 생육과 엽록소함량은 감소하였다. 광 조절 17일 째 어린잎채소 4종의 초장, 엽장, 엽폭, 경경, 생체중, 엽록소 함량 등의 생육은 무차광 NS 처리구에서 가장 높았다. 생육 초기 광조절에 따른 생육 후기 초장과 생체중 증가율이 어린잎채소 4종 모두 NS 또는 S8NS9 처리구에서 높았다. 따라서 벼 육묘장 다층 시스템에서의 공간 활용을 고려한 어린잎채소 재배시 차광이 많은 하부 공간은 생육초기에 활용하고, 수확기에는 광 확보가 이루어지는 상부에서 재배가 이루어짐이 적합하리라 본다. This study was conducted to investigate the effect of light control on growth of baby leaf vegetables (tatsoi, pak-choi, chinese cabbage ‘alpine’ and leaf lettuce ‘cheongchima’) in rice seedling tray. Light treatment controlled in non-shading (NS), shading for 8 days+non-shading for 9 days (S8NS9), non-shading for 8 days+shading for 9 days (NS8S9), and shading for 17 days (S17). Integrated solar radiation in NS was highest, and in S8NS9>NS8S9>S17 order. Integrated temperature did not shown difference among the treatments for growing periods. Growth and chlorophyll content of baby leaf vegetables were lowest in shading treatment for 8days. The highest growth characteristics (plant height, leaf length, leaf width, stem diameters, and fresh weight) and chlorophyll content of baby leaf vegetables was shown in NS. Increment rate of plant height and fresh weight of baby leaf vegetables were high in NS or S8NS9 as affected by light control for 8 days in early growth periods. These results suggest that we can utilize in low layer for early period and in high layer for harvest periods for baby vegetable production in rice seedling factory.

CAN통신을 이용한 H-브릿지 멀티레벨 인버터의 PWM 동기화 및 위상전이 방법

박영민(Y.M.Park),유한승(H.S.Yoo),장성영(S.Y.Jang),이현원(H.W.Lee),이세현(S.H.Lee),서광덕(K.D.Seo) 전력전자학회 2004 전력전자학술대회 논문집 Vol.- No.-

H-브릿지 멀티레벨 인버터는 여러 개의 단상 Power Cell을 직렬로 연결함으로써 저전압 전력용 반도체를 사용하여 고전압을 얻을 수 있고, 정현파에 가까운 출력전압 파형을 얻을 수 있는 멀티레벨 인버터 토폴로지이다. 본 토폴로지는 출력전압 레벨에 비례하여 Power Cell의 수가 증가하므로, 주제어기의 연산능력에 대한 부담증가와 신호선의 많아지는 단점이 있다. 따라서 Power Cell제어를 직접적인 PWM 신호가 아닌 통신을 사용함으로써 이러한 단점을 극복할수 있으며, 신뢰성 측면이나 보수/유지 측면에서도 유리하다. 본 논문은 산업현장에서 신뢰성을 인정받아 많이 사용되고 있는 직렬통신 방식의 일종인 CAN통신 인터럽터를 이용한 H-브릿지 멀티레벨 인버터 Power Cell의 PWM 동기화 및 위상전이 방법에 관한 것이다. 제안된 방법의 주요 장점은 주제어기와 셀 제어기 사이에 직렬통신(CAN)을 사용함으로써 주제어기와 셀 제어기의 신호선의 단순화, 주제어기의 부담 감소, Power Cell의 모듈화, 셀 단위의 보호동작 용이, 확장성 향상 그리고 제어 신호 및 Power Cell의 신뢰성을 향상에 있다. 13레벨로 구성된 H-브릿지 멀티레벨 인버터 시험을 통해 제안된 방법의 타당성과 신뢰성을 입증하였다.

Modified Panax ginseng extract regulates autophagy by AMPK signaling in A549 human lung cancer cells

Yoo, H.-S.,Kim, J. M.,Jo, E.,Cho, C.-K.,Lee, S.-Y.,Kang, H. S.,Lee, M.-G.,Yang, P.-Y.,Jang, I.-S. Spandidos Publications 2017 Oncology reports Vol.37 No.6

<P>Panax ginseng has been used worldwide as a traditional medicine for the treatment of cancer and other diseases. The antiproliferative activity of ginseng has been increased after enzymatic processing of ginseng saponin, which may result in the accumulation of minor saponins, such as Rh2, Rg3, compound K and protopanaxatriol type (PPT) in modified regular ginseng extract (MRGX). In the present study, the anticancer activity and the associated mechanisms of MRGX were investigated using A549 human lung cancer cells. To elucidate the mechanisms underlying the effects of MRGX, we performed a microarray analysis of gene expression in the A549 cells. Molecular mechanisms that were associated with the anticancer activity of MRGX were studied, with a special focus on the autophagy-related multiple signaling pathways in lung cancer cells. Microarray analyses elucidated autophagy-related genes affected by MRGX. Administration of MRGX at 100 mu g/ml induced punctate cytoplasmic expression of LC3, Beclin-1 and ATG5 and increased expression of endogenous LC3-II whereas 50 mu g/ml did not inhibit the proliferation of A549 cells. Compared to the control cells, in cells treated with MRGX at 100 mu g/ml, the level of p-Akt was increased, while that of mTOR-4EBP1 was decreased. Downregulation of mTOR and 4EBP1 in the MRGX-treated cells was found not to be a p-Ulk (S757)-dependent pathway, but a p-Ulk (S317)-dependent autophagic pathway, using AMPK. These data suggest that MRGX regulates AMPK and induces autophagy in lung cancer cells.</P>

Triazole-bridged magnetic M(II) assemblies (M=Co, Ni) capped with the end-on terephthalate dianion involving multi-intermolecular contacts

Yoo, H.S.,Lim, J.H.,Kang, J.S.,Koh, E.K.,Hong, C.S. Pergamon Press 2007 Polyhedron Vol.26 No.15

Two dimeric complexes [M<SUB>2</SUB>(atrz)<SUB>3</SUB>(H<SUB>2</SUB>O)<SUB>4</SUB>(tp)<SUB>2</SUB>].11H<SUB>2</SUB>O [M=Co(1.11H<SUB>2</SUB>O), Ni(2.11H<SUB>2</SUB>O); tp=terephthalate, atrz=4-aminotriazole] were constructed by triply-bridged triazole ligands and terminal tp groups. Among the dinuclear assemblies, three types of intermolecular interactions (hydrogen bond, face-to-face π-π and edge-to-face CH-π contacts) as well as intramolecular hydrogen bonding are involved, eventually leading to the formation of a 3D network. Magnetic data show that moderate antiferromagnetic interactions between two metal centers communicate through triazole groups and non-negligible interdimer antiferromagnetic couplings are also involved in this system.

간호대학생의 정보활용능력의 영향 요인에 대한 연구 : 셀프 리더십을 중심으로

최선엽,최가을,이현정,유명혜,안서현,박수현,하재영,홍신해,김한나,김지아 이화여자대학교 간호과학대학 2015 이화간호학회지 Vol.- No.49

Purpose: This study identifies the factors in nursing undergraduate curriculum related to improved information literacy, and the degree of relationship between information literacy and self-leadership among nursing undergraduate students. Method: Participants were 338 nursing undergraduates selected by convenience sampling at 19 Korean universities. Instruments were the self-leadership tool by Manz(1983), modified by Cho(2003) and the information literacy tool developed by Rhee(2008). The data were analyzed by t-test, ANOVA, and hierarchial multiple regression analysis with SPSS 22.0 Windows software. Results: Participants’ age(F=2.962, p<.001), grade(F=5.757, p=.001), experience in clinical nursing-practice(t=3.792, p<.001), GPA(F=3.373, p=.019) and experience in informatics education (t=3.291, p<.001) were statistically significant differences in the information literacy. Age(F=4.995, p=.007), Religion (t=3.593, p<.001), GPA (F=8.878, p<.001), satisfaction with the major subject (t=-4.399, p<.001) and the degree of information education necessity(t=1.993, p=.047) showed statistically significant differences in the self-leadership. Also there was a strong correlation between information literacy and self-leadership (Pearson’s r=.578, p<.001). Hierarchical-regression analysis revealed that the better self-leadership was associated with the higher information literacy(Adjusted R²=.355, R²=.382, p<.001). However, age, time using a computer, grade, religion, GPA, satisfaction with nursing as a major, and experience in informatics education were not significantly associated with information literacy. Conclusion: These findings implied the importance of educating information literacy which is a foundation for evidence-based-practice for nursing students. Considering the importance of self-leadership on information literacy, it is also essential to develop the current nursing undergraduate curriculum for maximizing the effectiveness of information literacy education reflecting the relationship between self-leadership and information literacy.

Carbon nanotube-based biosensor for detection of matrix metallopeptidase-9 and S-100B

Lee, H.S.,Oh, J.S.,Chang, Y.W.,Park, Y.J.,Shin, J.S.,Yoo, K.H. 한국물리학회 2009 Current Applied Physics Vol.9 No.4_SUP

We fabricated carbon nanotube (CNT)-based biosensor with field effect transistor structure for detection of matrix metallopeptidase-9 (MMP-9) and S-100B. To minimize contact effects, the metal electrodes were passivated with SiO<SUB>x</SUB> film, and anti-MMP-9 and S-100B antibody were immobilized on the CNT surface using a chemical linker. When MMP-9 or S-100B antigen was added to bind anti-MMP-9 or S-100B antibody, the decrease in electrical conductance was observed. We have also investigated the dependence of MMP-9 and S-100B concentration on the conductance change. A linear relationship was found between the conductance and the concentration in semi-logarithm scale.