• Title/Summary/Keyword: I-kBa

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Thermal Stability of Superconductor NdBCO Sintered at Various Oxygen Partial Pressures (다양한 산소분압에서 소결한 NdBCO 초전도체의 열적 안정성)

  • Chung, J.K.;Kim, W.J.;Park, S.C.;Kang, S.G.;Lim, Y.J.;Kim, C.J.
    • Progress in Superconductivity
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    • v.10 no.2
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    • pp.133-138
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    • 2009
  • The $Nd_{1+x}Ba_{2-x}Cu_3O_{7-{\delta}}$(Nd123) superconductor exhibits high performance in high magnetic field and high temperature. We have studied phase stability for Nd123 under reduced oxygen partial pressure and various heat-treatment conditions. The main phase is Nd123 and some samples contain small amounts of Nd422 depending on the temperature and oxygen partial pressure. The decomposition temperature decreases with decreasing oxygen partial pressure from $1052^{\circ}C(P(O_2)$=150 Torr) to about $845^{\circ}C(P(O_2)$=0.1 Torr). The liquidus line was steeper temperature with decreasing oxygen partial pressure. In same condition of oxygen partial pressure, the region of stable Nd123 phase was formed at slightly higher temperature than the region of stable YBCO phase.

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Biliary Atresia with Extrahepatic Biliary Cyst (간 외 담관 낭성확장이 동반된 선천성 담도폐쇄증)

  • Chung, Jae-Hee;Lee, Han-Hong;Cha, Seon-Wook;Song, Young-Tack
    • Advances in pediatric surgery
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    • v.10 no.2
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    • pp.136-141
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    • 2004
  • Biliary atresia (BA) with extrahepatic biliary cysts (EHBC) is a rare disease. It has been generally recognized as type I (correctable with cystic dilatation), which means a good prognosis. From a total of 73 patients with BA who underwent operation from September 1988 to September 2003 at our institute, 7 (9.6 %) cases of type III BA with EHBC (uncorrectable with cystic dilatation) are reviewed. Clinical findings, laboratory data, radiologic findings, treatment methods and outcomes were reviewed. Female was more prevalent (male to female ratio; 2:5). All cases were type III with EHBC according to the intraoperative cholangiography, and underwent Kasai' s portoenterostomy. The mean age was 57 days at operation. Three patients(42.9 %) are long term survivors. Further evaluation is needed to determine the correlation between prognostic factors and outcome for.

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Callus induction and plant regeneration of Iris dichotoma Pall. in endangered species

  • Bae, Kee-Hwa;Yoo, Kyoung-Hwa;Lee, Hak-Bong;Yoon, Eui-Soo
    • Journal of Plant Biotechnology
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    • v.39 no.3
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    • pp.182-188
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    • 2012
  • Iris dichotoma Pall. is an important endangered plant belonging to the family Iridaceae. A method was developed for the rapid micropropagation of I. dichotoma through plant regeneration from leaf, rhizome, and root explant-derived calli. Leaf, rhizome, and root segments were cultured on Murashige and Skoog (MS) medium supplemented with 2,4-dichlorophenoxy acetic acid (2,4-D; $0-3.0mg{\cdot}L^{-1}$) for callus induction. Callus production was highest at $1.0mg{\cdot}L^{-1}$ 2,4-D, where 73.8% and 45.5% of cultured rhizome and root cuttings, respectively, produced calli. The viable calli were maintained at an induced concentration of 2,4-D ($3.0mg{\cdot}L^{-1}$). They were then transferred to MS medium supplemented with various concentrations of 2,4-D ($0-3.0mg{\cdot}L^{-1}$) in combination with 6-benzyladenine (BA: 0, 1.0 and $3.0mg{\cdot}L^{-1}$) for adventitious shoot regeneration. The addition of a low concentration of 2,4-D into BA-containing medium significantly increased the frequency of shoot regeneration in leaf, rhizome, and root-derived calli. The highest number of adventitious shoots (26.4 per callus) formed at $0.5mg{\cdot}L^{-1}$ 2,4-D and 1.0 mg/l BA. For rooting of the shoots, half- strength MS medium supplemented with different concentrations of indole 3-butyric acid (IBA) $0-3.0mg{\cdot}L^{-1}$ was tested. The optimal results were observed using half-strength MS medium supplemented with $1.0mg{\cdot}L^{-1}$ IBA, on which 98% of the regenerated shoots developed roots with an average of 3.5 roots per shoot within 45 days. The plantlets raised in vitro were acclimatized and transferred to soil with 95% success. This in vitro propagation protocol will be useful for conservation and mass propagation of this endangered plant.

Monitoring Research for Heavy Metals as Endocrine Disruptors in Herbal Medicines and Ssangwha-Tang (한약재와 탕액(쌍화탕)중 내분비계 장애물질로서의 개별 중금속의 함량 연구( I ))

  • Kim, Jin-Sook;Hwang, Sung-Won;Kim, Jong-Moon;Ma, Jin-Yeul
    • Korean Journal of Oriental Medicine
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    • v.6 no.1
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    • pp.117-122
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    • 2000
  • The purpose of this study is to compare the contents of heavy metals of boiled ssangwhatang with those of herbal ingredients which are composed of ssangwhatang. Ssangwhatang is used for antifatigue, tonic and so on. With industrial development, our environment has been very polluted. Herbal medicines also are seriously contaminated by heavy metals and pesticides. The herbal medicines of ssangwhatang were bought at 10 defferent markets. The contents of 14 heavy metals(Ag, As, Ba, Cd, Cr, Cu, Fe, Hg, Mn, Ni, Pb, Sb, Sn, Zn) were analysed using ICP. It was found out that 7 heavy metals(Pb, As, Ba, Cd, Hg, Sb, Sn) were not detected at all in boiled ssangwhatangs. But they were detectable in all ssangwhatangingredients before boiling. For example, the content of Pb in one pack of ssangwhatang before boiling was $0.039^{\circ}{\pm}0.005mg$ and Pb in boiled one was not detected. Herbal medicine itself is seriously contaminated by heavy metals. These results suggest that boiled ssangwhatang which we take is safe from the contamination of heavy metals.

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Inhibitory Effects of Piperine on the Production of Nitric Oxide, Interleukin-10 and Interleukine-12 in Murine Peritoneal Macrophages (복강 대식세포에서 피페린의 일산화질소, 인테루킨-10과 인테루킨-12의 억제 효과)

  • Bae, Gi-Sang;Lee, Ju-Sung;Sung, Kang-Keyng;Park, Sung-Joo
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.23 no.2
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    • pp.452-456
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    • 2009
  • The purpose of this study was to investigate the anti-inflammatory effects and cellular mechanism of piperine on murine peritoneal macrophages. To evaluate the effects of piperine, we examined the production of nitric oxide (NO), interleukin (IL)-10 and IL-12. To investigate inhibitory mechanism of piperine, we examined the MAPKs and Ik-Ba in murine peritoneal macrophages, Piperine itself does not have any cytotoxic effect and reduced lipopolysaccharid (LPS), Poly(I:C), CpG-ODN -induced production of NO, IL-10 and IL-12 in peritoneal macrophages. Piperine inhibited the activation of extracelluar signal-regulated kinase (ERK 1/2) and c-Jun NH2-terminal kinase (JNK 1/2) not the activation of p38 and the degradation of inhibitory kappa B a (Ik-Ba) in the LPS-stimulated murine peritoneal macrophages.ln conclusion, Piperine down-regulated LPS-induced production of NO, IL-10 and IL-12, which could provide a clinical basis for anti-inflammatory properties of piperine.

Advances in High Emission Sc2O3-W Matrix Cathode Materials

  • Wang, Jinshu;Yang, Yunfei;Liu, Wei;Wang, Yiman
    • Applied Microscopy
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    • v.46 no.1
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    • pp.20-26
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    • 2016
  • Our work on $Sc_2O_3-W$ matrix dispenser cathodes had been reviewed in this paper. The cathode with uniform distribution of $Sc_2O_3$ had been obtained using liquid-liquid doping method. The cathode had excellent emission property, i.e., the emission current density in pulse condition could reach over $35A/cm^2$. It was found that the cathode surface was covered by a Ba-Sc-O active substance multilayer with a thickness of about 100 nm, which was different from the monolayer and semiconducting layer in thickness. Furthermore, the observation results displayed that nanoparticles appeared at the growth steps and the surface of tungsten grains of the fully activated cathode. The calculation result indicated that the nanoparticles could cause the increase of local electric field strengths. We proposed the emission model that both the Ba-Sc-O multilayer and the nanoparticles distributing mainly on the growth steps of the W grains contributed to the emission. The future work on this cathode has been discussed.

ROTATION AND SURFACE ABUNDANCE PECULIARITIES IN A-TYPE STARS

  • Takeda, Yoichi;Han, In-Woo;Kang, Dong-Il;Lee, Byeong-Cheol;Kim, Kang-Min
    • Journal of The Korean Astronomical Society
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    • v.41 no.4
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    • pp.83-98
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    • 2008
  • In an attempt of clarifying the connection between the photospheric abundance anomalies and the stellar rotation as well as of exploring the nature of "normal A" stars, the abundances of seven elements (C, O, Si, Ca, Ti, Fe, and Ba) and the projected rotational velocity for 46 A-type field stars were determined by applying the spectrum-fitting method to the high-dispersion spectral data obtained with BOES at BOAO. We found that the peculiarities(underabundances of C, O, and Ca; an overabundance of Ba) seen in slow rotators efficiently decrease with an increase of rotation, which almost disappear at $v_esin\;i{\gtrsim}100km\;s^{-1}$. This further suggests that stars with sufficiently large rotational velocity may retain the original composition at the surface without being altered. Considering the subsolar tendency(by several tenths dex below) exhibited by the elemental abundances of such rapidly-rotating (supposedly normal) A stars, we suspect that the gas metallicity may have decreased since our Sun was born, contrary to the common picture of galactic chemical evolution.

The High Performance Liquid Chromatography (HPLC) Analysis of Polycyclic Aromatic Hydrocarbons (PAHs) in Oysters from the Intertidal and Subtidal Zones of Chinhae Bay, Korea

  • Lee Ki Seok;Noh Il;Lim Cheol Soo;Chu Su Dong
    • Environmental Sciences Bulletin of The Korean Environmental Sciences Society
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    • v.2 no.1
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    • pp.57-68
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    • 1998
  • Polycyclic aromatic hydrocarbons (PAMs) are ubiquitous contaminants in marine environments. PAMs enter estuarine and nearshore marine environment via several routes such as combustion of fossil fuels, domestic and industrial effluents and oil spills. PAHs have been the focus of numerous studies in the world because they are potentially carcinogenic, mutagenic, and teratogenic to aquatic organisms and humans from consuming contaminated food. However, one can hardly find any available data on PAM content in marine organisms in Korea. The present study was carried out in order to determine PAM content in oysters from the intertidal and subtidal zones of Chinhae Bay, which is located in near urban communities and an industrial complex, and the bay is considered to be a major repositories of PAHs. 16 PAHs were analyzed by High Performance Liquid Chromatography (HPLC) with uv/vis and fluorescence detectors in oysters: they are naphthalene (NPTHL), acenaphthylene (ANCPL), acenaphthylene (ACNPN), fluorene (FLURN), phenanthrene (PHEN), anthracene (ANTHR), fluoranthene (FLRTH), pyrene (PYR), benzo(a)anthracene (BaA), chrysene (CHRY), benzo(b)fluoranthene (BbF), benzo(k)fluoranthene (BkF), benzo(a)pyrene (BaP), dibenz(a,h)anthracene(DahA), benzo(g,h,i)peryne (BghiP) and indeno(1,2,3,-cd)pyrene (I123cdP). The PAM contents in oysters from the intertidal and subtidal zones of Chinhae Bay ranged from < 0.1 to 992.0 ug/kg (mean $69.8\pm9.8$ ug/kg).

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Stability of 5-FU and Tegafur in Biological Fluids of Rats (흰쥐 생체시료 중 5-플루오로우라실 및 테가푸르의 안정성)

  • Jang, Ji-Hyun;Park, Jong-Kook;Kang, Jin-Hyoung;Chung, Suk-Jae;Shim, Chang-Koo;Kuh, Hyo-Jeong
    • Journal of Pharmaceutical Investigation
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    • v.34 no.3
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    • pp.161-168
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    • 2004
  • 5-Fluorouracil (5-FU) is an antimetabolite anticancer agent active against many types of solid tumors. Tegafur (TF), a prodrug of 5-FU, is frequently used in combination with uracil as dihydropyrimidine dehydrogenase (DPD) inhibitory fluoropyrimidine. We studied the stability of 5-FU and TF in biological fluids of rats and determined their bioavailability (BA) and excretion into bile, and urine. The drug concentrations were analyzed by an HPLC method. At room temperature, there was a 14-30% decrease in the concentration of 5-FU and TF in bile, urine, and plasma specimen at 10 and $100\;{\mu}g/ml$ over 240 min. No significant difference was noted among the sample types or between two different concentrations of 10 and $100{\mu}g/ml$. The decrease in drug concentration was significantly less in samples kept on ice (6-12%) for both drugs. These data indicate that biological fluid samples containing 5-FU or TF in plasma, urine, or bile should be placed on ice during the sample collection. Following these storage guidelines, samples were collected after administration 50 mg/kg of each drug via i.v. or oral route. BA was 1.5 folds greater for TF (60%) than that of 5-FU (42%). Approximately 0.52 and 3.3% of the i.v. doses of 5-FU and TF was excreted into bile, respectively. Renal clearance of 5-FU was about 16% of its total body clearance. These results suggest that instability of 5-FU and TF in biological fluids should be considered in pharmacokinetic or pharmacogenomic studies.

Change in Properties of (Ba1-xLax)Fe3+1-tFe4+tO3-y System Depending on Heat Treatment Conditions

  • Lee, Eun-Seok;Lee, Seo-Jin
    • Transactions on Electrical and Electronic Materials
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    • v.18 no.6
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    • pp.311-315
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    • 2017
  • The perovskite system $(Ba^{2+}{_{1-x}}La^{3+}{_x})Fe^{3+}{_{1-t}}Fe^{4+}{_t}O_{3-y}$ (y = (1 - x --t)/2) having a composition of x = 0.0, 0.1, 0.2, and 0.3 showedean increase in $Fe^{4+}$ mole ratios with an increase in oxygen partial pressure ($N_2{\rightarrow}air{\rightarrow}O_2$), and with an increasefin s, the $Fe^{3+}$ quantity decreased and oxygen content (3-y value) increased. For each N sampls heat-treated in $N_2$ gas, a considerable weight gain, i.e.g a steadynincrease if oxygen content, was observed in the TGA data on the cooling process. The conductivity values at a constant temperature were in the order of $N_2$$O_2$; the respective log ${\sigma}$ values (${\Omega}^{-1}{\cdot}cm^{-1}$) at 323 K of the BL0 sample were -5.75 (BL0-N), -3.39 (BL0-A), and -0.53 (BL0-O). The mixed valencies of $Fe^{3+}$ and $Fe^{4+}$ ions in each sample were also confirmed by both the oxidation curve above 350 mV and the cathodic reduction curve below 200 mV from cyclic voltammetry.