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991.
Won HS Kim HG Yun YS Jeon EK Ko YH Kim YS Kim YO Yoon SA 《Hemodialysis international. International Symposium on Home Hemodialysis》2012,16(1):31-37
Anemia is a common complication in dialysis patients because of their relative erythropoietin deficiency. Despite treatment with erythropoiesis-stimulating agents (ESAs), some patients experienced ESA hyporesponsiveness. We evaluated the clinical and laboratory factors that affect ESA hyporesponsiveness and investigated the relationships between hepcidin, inflammatory markers, and the iron profiles of hemodialysis patients. Sixty-eight patients receiving hemodialysis at a single institution were evaluated in a cross-sectional study. The patients were divided into tertiles based on the ESA hyporesponsiveness index (EHRI), defined as the weekly ESA dose per kilogram of body weight divided by the hemoglobin level. The mean EHRI values for each tertile were 3.3 ± 1.2 (T1), 10.2 ± 2.9 (T2), and 24.5 ± 11.6 (T3). The mean serum erythropoietin levels were significantly higher in the Q3 and Q4 groups. Thus, patients with ESA hyporesponsiveness showed relative resistance to erythropoietin therapy. In univariate and multivariate analyses, patients in the third tertile of EHRI showed significantly higher mean interleukin-6 (IL-6) levels. Serum C-reactive protein (CRP) levels showed a similar trend, but the differences were not significant. Serum hepcidin levels tended toward lower mean values in the third tertile of EHRI. No relationship was observed between hepcidin and inflammatory markers or iron status. In conclusion, IL-6, but not CRP, is a strong predictor of ESA hyporesponsiveness in hemodialysis patients who have sufficient iron. It may be difficult to use hepcidin as an independent clinical marker because of the many factors that influence it and their interactions. 相似文献
992.
We fabricated the vertically-aligned zinc oxide (ZnO)/silicon (Si) double nanostructures by simple processes using the metal-assisted chemical etching and a subsequent hydrothermal synthesis, and their optical property was investigated. For efficient antireflection characteristics, Si nanostructures were optimized by changing the size of the dewetted silver (Ag) at different etching times. The thermally dewetted Ag nanoparticles or semi-island films as metal catalysts were controlled by the Ag film thickness and dewetting temperature. To form the ZnO/Si double nanostructures, ZnO nanorods were synthesized on the chemically etched Si nanostructures using a thin sputtered ZnO seed layer. The grown ZnO nanorod arrays (NRAs) exhibited good crystallinity and further reduced the surface reflection due to their antireflective property. The ZnO/Si double nanostructures showed the increased peak intensity of X-ray diffraction as well as the significantly reduced solar weight reflectance of 6.05% compared to 11.71% in the ZnO NRAs on the flat Si substrate. Also, the enhanced antireflection property of ZnO/Si double nanostructures was theoretically analyzed by performing the rigorous coupled wave analysis simulation. 相似文献
993.
For this investigation of the Ge behavior of condensed Si(1-y)Ge(y) (y > x) cores during the oxidation of Si(1-x)Ge(x) nanowires, Si(1-x)Ge(x) nanowires were grown in a tube furnace by the vapor-liquid-solid method and thermally oxidized. The test results were characterized using several techniques of transmission electron microscopy. The two types of Ge condensation are related to the diameter and Ge content of the nanowires. The consumption of Si atoms in prolonged oxidation caused the condensed SiGe cores to become Ge-only cores; and the continuous oxidation resulted in the oxidation of the Ge cores. The oxidation of Ge atoms was confirmed by scanning transmission electron microscopy. 相似文献
994.
Lee W Yoo B Kim K Lee DK Kim H Ko MJ 《Journal of nanoscience and nanotechnology》2012,12(2):1492-1496
The compact and thin TiO2 blocking layers (c-TiO2) were formed on F-doped SnO2 (FTO) substrate in quantum dots-sensitized solar cells (QSSCs) by chemical deposition. The c-TiO2 layers induced indirect contact between electrolyte and FTO electrode, which reduced leakage in QSSCs. The QSSCs showed power conversion efficiency (Eff) of 3.85% in the presence of c-TiO2 layers which leads to 21% improved compared to that without c-TiO2 layers (Eff = 3.18%). The presence of the c-TiO2 layers in QSSCs also improved the stability under illumination. 相似文献
995.
Electrocatalytic performances of phthalocyanines (Pcs) involving N-benzyl-4-phenyloxyacetamide moieties, dispersed on a high-surface area carbon substrate, Vulcan XC-72 (VC) and Nafion (Nf), towards oxygen reduction in acidic medium were determined and compared. The VC/Nf/CoPc(5) catalyst showed much higher catalytic activity than those of the other Pc(1–4)-based catalysts (H2Pc 1, ZnPc 2, NiPc 3 and CuPc 4) and that of unsubstituted CoPc-based one. The comparison of the performance of VC/Nf/Pt-5 dual catalyst with that of VC/Nf/Pt one indicated that the former can be a good alternative to the latter as a cathode catalyst both in direct methanol and H2/O2 fuel cell applications. 相似文献
996.
Wentao Zhai Yoorim Ko Wenli Zhu Anson Wong Chul B. Park 《International journal of molecular sciences》2009,10(12):5381-5397
The crystallization and melting behaviors of linear polylactic acid (PLA) treated by compressed CO2 was investigated. The isothermal crystallization test indicated that while PLA exhibited very low crystallization kinetics under atmospheric pressure, CO2 exposure significantly increased PLA’s crystallization rate; a high crystallinity of 16.5% was achieved after CO2 treatment for only 1 min at 100 °C and 6.89 MPa. One melting peak could be found in the DSC curve, and this exhibited a slight dependency on treatment times, temperatures, and pressures. PLA samples tended to foam during the gas release process, and a foaming window as a function of time and temperature was established. Based on the foaming window, crystallinity, and cell morphology, it was found that foaming clearly reduced the needed time for PLA’s crystallization equilibrium. 相似文献
997.
Hyun Jun Ko Jae-ha Myung Ji-Hwan Lee Sang-Hoon Hyun Jong Shik Chung 《International Journal of Hydrogen Energy》2012
This paper investigates a (La0.6Sr0.4)(Co0.2Fe0.8)O3 (LSCF)–Y0.16Zr0.92O1.96 (YSZ)–Gd0.1Ce0.9O2−δ (GDC) dual composite cathode to achieve better cathodic performance compared to an LSM/GDC–YSZ dual composite cathode developed in previous research. To synthesize the structures of the LSCF/GDC–YSZ and LSCF/YSZ–GDC dual composite cathodes, nano-porous composite cathodes containing LSCF, YSZ, and GDC were prepared by a two-step polymerizable complex (PC) method which prevents the formation of YSZ–GDC solid solution. At 800 °C, the electrode polarization resistance of the LSCF/YSZ–GDC dual composite cathode showed to be significantly lower (0.075 Ω cm2) compared to that of a commercial LSCF–GDC cathode (0.195 Ω cm2), a synthesized LSCF/GDC–YSZ dual composite cathode (0.138 Ω cm2), and an LSM/GDC–YSZ dual composite cathode (0.266 Ω cm2) respectively. Moreover, the Ni–YSZ anode-supported single cell containing the LSCF/YSZ–GDC dual composite cathode achieved a maximum power density of 1.24 W/cm2 and showed excellent durability without degradation under a load of 1.0 A/cm2 over 570 h of operation at 800 °C. 相似文献
998.
In addition to the conversion efficiency of a photovoltaic panel, the maximum power point tracking (MPPT) method also plays a central role to harvest most energy out of sun. The MPPT unit on a moving vehicle must keep tracking accuracy high in order to compensate rapid change of insolation due to dynamic motion of the vehicle. In this paper, some problems of a PV system associated with a moving vehicle are addressed, and a modified quadratic maximization MPPT algorithm is proposed. Theoretical PV performance is linked to the experimental test followed by the Sandia dynamic test protocol to verify the proposed MPPT method. Finally, experimental result on a model ship is discussed. 相似文献
999.
C-reactive protein (CRP) is an acute phase protein whose levels are increased in many disorders. Levels greater than 3 μg/mL serum have hitherto been considered to indicate pathology, but there is increasing interest in assessments between 0.1 and 10 μg/mL, which have been found to correlate with severity of risk for cardiovascular disease. We report herein the generation of both antibody and Affimer based impedance immunoassays for CRP that are substantially more sensitive than clinically utilized immunonephelometry and immunoturbidity assessments. Significant in this study is not only the use of a constrained peptide to detect a clinically important target but also that derived electrochemical impedance assays can be highly sensitive even with probes whose relatively weak (μM) affinities are not amenable to target detection by surface plasmon resonance (SPR). Key to this finding is acknowledging that receptive surfaces of comparatively low initial steric bulk and charge transfer resistance are especially primed to be highly responsive to target binding in electroanalytical assays of this type. 相似文献
1000.
LA Tai YT Kang YC Chen YC Wang YJ Wang YT Wu KL Liu CY Wang YF Ko CY Chen NC Huang JK Chen YF Hsieh TR Yew CS Yang 《Analytical chemistry》2012,84(15):6312-6316
Transmission electron microscopy (TEM) is a unique and powerful tool for observation of nanoparticles. However, due to the uneven spatial distribution of particles conventionally dried on copper grids, TEM is rarely employed to evaluate the spatial distribution of nanoparticles in aqueous solutions. Here, we present a microchip nanopipet with a narrow chamber width for sorting nanoparticles from blood and preventing the aggregation of the particles during the drying process, enabling quantitative analysis of their aggregation/agglomeration states and the particle concentration in aqueous solutions. This microchip is adaptable to all commercial TEM holders. Such a nanopipet proves to be a simple and convenient sampling device for TEM image-based quantitative characterization. 相似文献