5,508 research outputs found

    Improving efficiency roll-off in organic light emitting devices with a fluorescence-interlayer-phosphorescence emission architecture

    Get PDF
    Organic light emitting devices (OLEDs) with a fluorescence-interlayer- phosphorescence emission layer structure (FIP EML) has been proposed to solve the efficiency roll-off issue effectively. Efficient green OLED based on FIP EML exhibiting only 26% roll-off in the luminance efficiency, which is lower than the typical roll-off of 51% for conventional phosphorescent OLEDs with single EML operated at 5-150 mA/cm2 range, has been demonstrated. Such enhancement should be attributed to the improved carrier balance, the exciton redistribution in recombination zone, the suppression of nonradiative exciton quenching processes, and the elimination of energy transfer loss offered by the FIP EML structure. © 2009 American Institute of Physics.published_or_final_versio

    Risk of liver cancer in patients with hepatitis B or C

    Get PDF
    Key Messages1. Among hepatitis B virus carriers, infection with genotype C significantly increases the risk of developing hepatocellular cancer compared to those without this genotype.2. Among hepatitis C virus carriers, infection with genotype 1b increases the risk of hepatocellular cancer two fold compared to controls without this genotype.3. Such increased risk should be explained as risk over and above the existing risk associated with each infection.4. Hepatitis C virus genotypes1a and 2a are associated with decreased risk of hepatocellular cancer.published_or_final_versio

    Control of the strain and magnetoresistance of LaMnO[sub 3+δ] thin films using the magnetostriction of Terfenol-D alloy

    Get PDF
    Author name used in this publication: Y. WangAuthor name used in this publication: H. L. W. ChanAuthor name used in this publication: C. L. ChoyAuthor name used in this publication: H. S. Luo2010-2011 > Academic research: refereed > Publication in refereed journalVersion of RecordPublishe

    Abnormal phase transitions for tetragonal (1-x)Pb(Mg[sub ⅓]Nb[sub ⅔])O₃-xPbTiO₃ single crystals at low temperature

    Get PDF
    2004-2005 > Academic research: refereed > Publication in refereed journalVersion of RecordPublishe

    Effects of ferroelectric polarization and converse piezoelectric effect induced lattice strain on the electrical properties of La[sub 0.7]Sr[sub 0.3]MnO₃ thin films

    Get PDF
    Author name used in this publication: R. K. ZhengAuthor name used in this publication: J. WangAuthor name used in this publication: X. Y. ZhouAuthor name used in this publication: Y. WangAuthor name used in this publication: H. L. W. ChanAuthor name used in this publication: C. L. ChoyAuthor name used in this publication: H. S. Luo2005-2006 > Academic research: refereed > Publication in refereed journalVersion of RecordPublishe

    Tuning the electrical properties of La[sub 0.75]Ca[sub 0.25]MnO₃ thin films by ferroelectric polarization, ferroelectric-field effect, and converse piezoelectric effect

    Get PDF
    2006-2007 > Academic research: refereed > Publication in refereed journalVersion of RecordPublishe

    Effect of different rhBMP-2 and TG-VEGF ratios on the formation of heterotopic bone and neovessels

    Get PDF
    Bioengineered bone substitutes might represent alternatives to autologous bone grafts in medically compromised patients due to reduced operation time and comorbidity. Due to the lack of an inherent vascular system their dimension is limited to the size of critical bone size defect. To overcome this shortcoming, the experiment tried to create heterotopic bone around vessels. In vivo, a two-component fibrin and thrombin gel containing recombinant bone morphogenic protein (rhBMP-2) and transglutamate vascular endothelial growth factor (TG-VEGF) in different ratios, respectively, was injected into a dimensionally stable membrane tube, wrapped around the femoral vessel bundle in twelve New Zealand white rabbits. Sacrifice occurred eight weeks postoperatively. Microcomputed tomography of the specimens showed significantly increased bone volume in the rhBMP-2 to TG-VEGF ratio of 10 to 1 group. Histology showed new bone formation in close proximity to the vessel bundle. Immunohistochemistry detected increased angiogenesis within the newly formed bone in the rhBMP-2 to TG-VEGF ratios of 3 to 1 and 5 to 1. Heterotopic bone was engineered in vivo around vessels using different rhBMP-2 and TG-VEGF ratios in a fibrin matrix injected into a dimensionally stable membrane tube which prevented direct contact with skeletal muscles.published_or_final_versio

    Chlorophyll derivatives/MXene hybrids for photocatalytic hydrogen evolution: Dependence of performance on the central coordinating metals

    Get PDF
    Development of efficient photocatalytic hydrogen evolution reaction (HER) with illumination of visible light is challenging. In this work, five chlorophyll derivatives (M-Chls; M = H2/Cu/Ni/Co/Zn) with different central ions in its cyclic tetrapyrrole ring including free base, copper, nickel, cobalt, and zinc were synthesized and employed as the effective visible-light harvester for efficient HER. In addition, two-dimensional (2D) noble metal-free co-catalyst Ti3C2Tx MXene was used as an excellent electron capturer due to its outstanding conductivity property. These M-Chls are modified on the surface of Ti3C2Tx MXene with 2D accordion-like morphology by means of a simple deposition process to form noble metal-free Chl/Ti3C2Tx-based photocatalysts for HER. It is found that the best HER performance as high as 49 μmol/h/gcat was achieved with the Co-Chl@Ti3C2Tx hybrid, which was much higher than those of other M-Chl@Ti3C2Tx composites. This research provides a specific way to synthesize low-cost and environmentally friendly natural Chls for developing highly efficient photocatalytic HER through molecular engineering

    Scalp acupuncture for acute ischemic stroke: a meta-analysis of randomized controlled trials

    Get PDF
    Scalp acupuncture (SA) is a commonly used therapeutic approach for stroke throughout China and elsewhere in the world. The objective of this study was to assess clinical efficacy and safety of SA for acute ischemic stroke. A systematical literature search of 6 databases was conducted to identify randomized controlled trials (RCTs) of SA for acute ischemic stroke compared with western conventional medicines (WCMs). All statistical analyses were performed by the Rev Man Version 5.0. Eight studies with 538 participants were included in the studies. The studies were deemed to have an unclear risk of bias based on the Cochrane Back Review Group. Compared with the WCM, 6 RCTs showed significant effects of SA for improving neurological deficit scores (P < 0.01); 4 RCTs showed significant effects of SA for favoring the clinical effective rate (P < 0.01) However, the adverse events have not been documented. In conclusion, SA appears to be able to improve neurological deficit score and the clinical effective rate when compared with WCM, though the beneficial effect from SA is possibly overvalued because of generally low methodology of the included trials. No evidence is available for adverse effects. Rigorous well-designed clinical trials are needed.published_or_final_versio
    corecore