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991.
Ui-Jin Bae Jae Do Yang Sun-O Ka Jeung-Hyun Koo Seong Ji Woo Young-Rae Lee Hee Chul Yu Baik Hwan Cho Hui-Yuan Zhao Jae-Ha Ryu Sang-Myeong Lee Raok Jeon Byung-Hyun Park 《Experimental & molecular medicine》2014,46(8):e109
Hepatic ischemia/reperfusion (I/R) injury leads to oxidative stress and acute inflammatory responses that cause liver damage and have a considerable impact on the postoperative outcome. Much research has been performed to develop possible protective techniques. We aimed to investigate the efficacy of SPA0355, a synthetic thiourea analog, in an animal model of hepatic I/R injury. Male C57BL/6 mice underwent normothermic partial liver ischemia for 45 min followed by varying periods of reperfusion. The animals were divided into three groups: sham operated, I/R and SPA0355 pretreated. Pretreatment with SPA0355 protected against hepatic I/R injury, as indicated by the decreased levels of serum aminotransferase and reduced parenchymal necrosis and apoptosis. Liver synthetic function was also restored by SPA0355 as reflected by the prolonged prothrombin time. To gain insight into the mechanism involved in this protection, we measured the activity of nuclear factor-κB (NF-κB), which revealed that SPA0355 suppressed the nuclear translocation and DNA binding of NF-κB subunits. Concomitantly, the expression of NF-κB target genes such as IL-1β, IL-6, TNF-α and iNOS was significantly downregulated. Lastly, the liver antioxidant enzymes superoxide dismutase, catalase and glutathione were upregulated by SPA0355 treatment, which correlated with the reduction in serum malondialdehyde. Our results suggest that SPA0355 pretreatment prior to I/R injury could be an effective method to reduce liver damage. 相似文献
992.
Superior Rechargeability and Efficiency of Lithium–Oxygen Batteries: Hierarchical Air Electrode Architecture Combined with a Soluble Catalyst
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Hee‐Dae Lim Hyelynn Song Jinsoo Kim Hyeokjo Gwon Youngjoon Bae Kyu‐Young Park Jihyun Hong Haegyeom Kim Taewoo Kim Prof. Yong Hyup Kim Xavier Lepró Raquel Ovalle‐Robles Prof. Ray H. Baughman Prof. Kisuk Kang 《Angewandte Chemie (International ed. in English)》2014,53(15):3926-3931
The lithium–oxygen battery has the potential to deliver extremely high energy densities; however, the practical use of Li‐O2 batteries has been restricted because of their poor cyclability and low energy efficiency. In this work, we report a novel Li‐O2 battery with high reversibility and good energy efficiency using a soluble catalyst combined with a hierarchical nanoporous air electrode. Through the porous three‐dimensional network of the air electrode, not only lithium ions and oxygen but also soluble catalysts can be rapidly transported, enabling ultra‐efficient electrode reactions and significantly enhanced catalytic activity. The novel Li‐O2 battery, combining an ideal air electrode and a soluble catalyst, can deliver a high reversible capacity (1000 mAh g?1) up to 900 cycles with reduced polarization (about 0.25 V). 相似文献
993.
Application of high‐performance countercurrent chromatography for the isolation of steroidal saponins from Liriope plathyphylla
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Soo‐Jung Choi Janggyoo Choi Heejin Jeon Soo Kyung Bae Jaeyoung Ko Jinwoong Kim Kee Dong Yoon 《Journal of separation science》2015,38(1):18-24
High‐performance countercurrent chromatography (HPCCC) with electrospray light‐scattering detection was applied for the first time to isolate a spirostanol and a novel furostanol saponin from Liriope platyphylla. Due to the large differences in KD values between the two compounds, a two‐step HPCCC method was applied in this study. The primary HPCCC employed methylene chloride/methanol/isopropanol/water (9:6:1:4 v/v, 4 mL/min, normal‐phase mode) conditions to yield a spirostanol saponin ( 1 ). After the primary HPCCC run, the solute retained in the stationary phase (SP extract) in HPCCC column was recovered and subjected to the second HPCCC on the n‐hexane/n‐butanol/water system (1:9:10 v/v, 5 mL/min, reversed‐phase mode) to yield a novel furostanol saponin ( 2 ). The isolated spirostanol saponin was determined to be 25(S)‐ruscogenin 1‐O‐β‐d ‐glucopyranosyl (1→2)‐[β‐d ‐xylopyranosyl (1→3)]‐β‐d ‐fucopyranoside (spicatoside A), and the novel furostanol saponin was elucidated to be 26‐O‐β‐d ‐glucopyranosyl‐25(S)‐furost‐5(6)‐ene‐1β‐3β‐22α‐26‐tetraol‐1‐O‐β‐d ‐glucopyranosyl (1→2)‐[β‐d ‐xylopyranosyl‐(1→3)]‐β‐d ‐fucopyranoside (spicatoside D). 相似文献
994.
In this paper, we consider a non-Newtonian fluids with shear dependent viscosity in a bounded domain ${\Omega \subset \mathbb{R}^n, n = 2, 3}$ . For the power-law model with the viscosity as in (1.4), we show the global in time existence of a weak solution for ${q \geq \frac{11}{5}}$ when n = 3 (see Theorem 1.1), and the local in time existence of a weak solution for ${2 > q > \frac{3n}{n+2}}$ , when n = 2,3 (see Theorem 1.2). 相似文献
995.
996.
Intuitionistic fuzzy finite state machines 总被引:1,自引:0,他引:1
Young Bae Jun 《Journal of Applied Mathematics and Computing》2005,17(1-2):109-120
Using the notion of intuitionistic fuzzy sets, the concepts of intuitionistic fuzzy finite state machines (iffsm), intuitionistic successor s, intuitionistic subsystems, intuitionistic submachines, intuitionisticq-twins, and intuitionistic retrievable iffsm are introduce d, and related properties are studied. Relations between intuitionisticq-twins and intuitionisticq-related iffsm are given. A characterization of an intuitionistic retrievable iffsm is provided. 相似文献
997.
S.S. Yi J.S. Bae K.S. Shim B.K. Moon H.J. Seo J.H. Jeong J.H. Kim 《Applied Physics A: Materials Science & Processing》2005,80(4):727-730
Gd2O3:Eu3+ and Li-doped Gd2O3:Eu3+ luminescent thin films have been grown on Si(100) substrates using pulsed laser deposition. The films grown at different deposition conditions show different crystalline and morphology structures and luminescent characteristics. Although both cubic and monoclinic crystalline structures were observed in both Gd2O3:Eu3+ and Li-doped Gd2O3:Eu3+ films, the cubic structure becomes more dominant for Li-doped Gd2O3:Eu3+ films. The photoluminescence brightness data obtained from Li-doped Gd2O3:Eu3+ films indicate that Si(100) is a promising substrate for growth of high-quality Li-doped Gd2O3:Eu3+ thin-film red phosphor. In particular, the incorporation of Li+ ions into the Gd2O3 lattice induced a change of crystallinity and enhanced surface roughness. Two major factors to determine photoluminescence brightness for Li-doped Gd2O3:Eu3+ films were crystalline phase and surface roughness. The highest emission intensity was observed with Gd1.84Li0.08Eu0.08O3, whose brightness was a factor of 2.1 larger than that of Gd2O3:Eu3+ films. This phosphor is promising for applications in flat-panel displays. PACS 78.20.-e; 78.55.-m; 78.66.-w 相似文献
998.
Chang Hyun Bae Seung-Eon Ahn Dong-Jin Oh Jeong Sook Ha 《Applied Surface Science》2006,253(4):1758-1761
A simple synthesis route to high-quality sub-50 nm ZnO nanowires is reported, utilizing ZnO thin films grown by pulse laser deposition (PLD) as seed layers. Depending upon the PLD growth conditions, the surface morphology of the ZnO nanowires on ZnO film was distinctively different whereas the diameters were almost the same. With the increase of the concentration of zinc nitrate/methenamine solution from 0.002 to 0.02 M, the average diameter of the ZnO nanowire increased but remained sub-50 nm. The grown ZnO nanowires showed a high crystallinity with a low defect density confirmed by a sharp photoluminescence spectrum. 相似文献
999.
R. Kudrawiec M. Gladysiewicz J. Misiewicz S.R. Bank H.P. Bae 《Applied Surface Science》2006,253(1):152-157
Contactless electroreflectance (CER) spectroscopy has been applied to investigate the optical transitions in Ga(In)NAs/GaAs quantum well (QW) structures containing Sb atoms. The identification of the optical transitions has been carried out in accordance with theoretical calculations which have been performed within the framework of the effective mass approximation. Using this method, the bandgap discontinuity for GaN0.027As0.863Sb0.11/GaAs, Ga0.62In0.38As0.954N0.026Sb0.02/GaAs, and Ga0.61In0.39As0.963N0.017Sb0.02/GaN0.027As0.973/GaAs QW structures has been determined. It has been found that the conduction-band offset is ∼50 and ∼80% for GaN0.027As0.863Sb0.11/GaAs and Ga0.62In0.38As0.954N0.026Sb0.02/GaAs QWs, respectively. It corresponds to 264 and 296 meV depth QW for electrons and heavy-holes in GaN0.027As0.863Sb0.11/GaAs QW; and 520 and 146 meV depth QW for electrons and heavy-holes in Ga0.62In0.38As0.954N0.026Sb0.02/GaAs QW. In the case of the Ga0.61In0.39As0.963N0.017Sb0.02/GaN0.027As0.973/GaAs step-like QW structure it has been shown that the depth of electron and heavy-hole Ga0.61In0.39As0.963N0.017Sb0.02/GaN0.027As0.973 QW is ∼144 and ∼127 meV, respectively. 相似文献
1000.
The effect of surfactant on enzymatic digestibility was investigated during the pretreatment stage. Newspaper was pretreated
with an ammonia-hydrogen peroxide mixture on a shaking bath at 40°C and 130 strokes/min for 3 h. Two kinds of nonionic surfactants,
NP series and Tween series, were utilized. The effect of hydrophile-lipophile balance (HLB) value of both series surfactants
on digestibility was found to be negligible, even though de-inking efficiency was improved as HLB value was increased. The
effect of surfactant loading on digestibility was small, below 0.5 wt%, and negligible above 0.5 wt% at 60 international filter
paper units (IFPU). The percentage improvement in digestibility increased as enzyme loading decreased. Digestibility of NP-5-added
sample relative to control sample, increased significantly at an enzyme loading <60 IFPU, i.e., 19 and 13% at 15 and 30 IFPU,
respectively. Such an increase in digestibility was not explained clearly from the experimental results. It was also found
that ink removal before enzymatic hydrolysis is very important to enhance digestibility. 相似文献