Photoluminescence and resonant Raman scattering (RRS) were investigated in various sizes of ZnO quantum dots. The size dependent shift of exciton emission reveals quantum confinement effect as ...changing the band gap. Besides, it was also found the enhancement of RRS intensity and electron-phonon coupling diminishes with decreasing particle's diameter.
Efficient resonant Raman scattering (RRS) were observed in ZnO quantum dots (ZnO-QDs). The size dependent shift of UV-emission reveals quantum confinement governs the enhancement of RRS through ...modifying the phonon state density in ZnO-QDs.
The influence of annealing on the AgGaS
2 films grown by pulsed laser deposition has been investigated. The X-ray diffraction results show the AgGaS
2 films were found with preferential orientation ...(1
1
2) normal to the surface and silver droplets were diminished after the post-annealing. Photoluminescence (PL) measurements reveled the exciton energy is slightly red shifted that is possibly due to the thermal strain effect. The binding energy of the shallow donors is ∼28 meV determined from temperature dependent PL spectra. In addition, the A-exciton and the B/C-exciton could be observed in the transmittance spectra at room temperature.
Markers that could accurately predict responses to the general kinase inhibitor sorafenib are needed to better leverage its clinical applications. In this study, we examined a hypothesized role in ...the drug response for the growth arrest DNA damage-inducible gene 45β (GADD45β), which is commonly underexpressed in hepatocellular carcinoma (HCC) where sorafenib may offer an important new therapeutic option. The anticancer activity of sorafenib-induced GADD45β expression was tested in a panel of HCC cell lines and xenograft models. We found that GADD45β mRNA and protein expression were induced relatively more prominently in HCC cells that were biologically sensitive to sorafenib treatment. GADD45β induction was not found after treatment with either the mitogen-activated protein kinase-extracellular signal-regulated kinase (ERK) kinase (MEK) inhibitor U0126 or the Raf inhibitor ZM336372, suggesting that GADD45β induction by sorafenib was independent of Raf/MEK/ERK signaling activity. However, c-Jun NH2-terminal kinase (JNK) kinase activation occurred preferentially in sorafenib-sensitive cells. Small interfering RNA-mediated knockdown of GADD45βor JNK kinase limited the proapoptotic effects of sorafenib in sorafenib-sensitive cells. We defined the -339/-267 region in the GADD45β promoter containing activator protein-1 and SP1-binding sites as a crucial region for GADD45β induction by sorafenib. Together, our findings suggest that GADD45β induction contributes to sorafenib-induced apoptosis in HCC cells, prompting further studies to validate its potential value in predicting sorafenib efficacy.
We report the structural and optical properties of ten-period ZnO/Mg x Zn1–x O multiple quantum wells (MQWs) prepared on the most widely used semiconductor material, Si. The introduction of a ...nanometer thick high-k Y2O3 transition layer between Si (111) substrate and a ZnO buffer layer significantly improves the structural perfection of the MQWs grown on top of it. The high structural quality of the ZnO/Mg x Zn1–x O MQWs is evidenced by the appearance of pronounced high order satellite peaks in X-ray crystal truncation rods; high resolution cross-sectional transmission electron microscopy images also confirmed the regularly arranged well and barrier layers. When the well width is less than ∼2.7 nm, the quantum-confined Stark effect in MQWs can be negligible. Not only the increasing exciton-binding energy but also reducing exciton–phonon coupling determined in temperature-dependent photoluminescence spectra indicate quantum-size effect. Our results demonstrate that ZnO/Mg x Zn1–x O MQWs integrated on Si have great potential in UV optoelectronic device applications.
Dinitrosyl-iron complexes (DNICs) are stable carriers for nitric oxide (NO), an important biological signaling molecule and regulator. However, the insolubility of synthetic DNICs, such as Roussin's ...red ester (RRE), in water has impaired efforts to unravel their biological functions. Here, we report a water-soluble and structurally well-characterized RRE Fe( mu - SC sub(2)H sub(4)COOH)(NO) sub(2) sub(2) (DNIC-1) and a {Fe(NO) sub(2)} super(10) DNIC (PPh sub(2)(Ph-3-SO sub(3)Na)) sub(2)Fe(NO) sub(2) (DNIC-2), their NO-induced protein regulation, and their cellular uptake mechanism using immortalized vascular endothelial cells as a model. Compared with the most common NO donor, S-nitroso-N-acetyl-penicillamine (SNAP), the in vitro NO release assay showed that both DNICs acted as much slower yet higher stoichiometric NO-release agents with low cytotoxicity (IC sub(50) > 1 mM). Furthermore, L-cysteine facilitated NO release from SNAP and DNIC-1, but not DNIC-2, in a dose- and time-dependent manner. EPR spectroscopic analysis showed, for the first time, that intact DNIC-1 can either diffuse or be transported into cells independently and can transform to either paramagnetic protein bound DNIC in the presence of serum or DNIC-(Cys) sub(2) with excess L-cysteine under serum-free conditions. Both DNICs subsequently induced NO- dependent upregulation of cellular heat shock protein 70 and in vivo protein S-nitrosylation. We conclude that both novel water-soluble DNICs have potential to release physiologically relevant quantities of NO and can be a good model for deciphering how iron-sulfur-nitrosyl compounds permeate into the cell membrane and for elucidating their physiological significance.
Objective Ankylosing spondylitis (AS) is a form of chronic inflammatory spondyloarthritis (SpA) that causes pain and stiffness in spines or joints. Human leukocyte antigen B27 (HLA-B27) and B60 ...(HLA-B60) have been reported as major genetic risk factors of AS. In addition, rs13202464, located on major histocompatibility complex (MHC) region, showed high sensitivity (98.7%) and specificity (98.0%) for HLA-B27. Design The aim of our study is to test whether the interaction between HLA-B60 and HLA-B27 (rs13202464) can serve as a better predictor of AS. We have genotyped HLA-B60 and rs13202464 among 471 patients with AS and 557 healthy subjects. Combined risk factors were investigated to test the biological interaction. Results Our results indicated that the relative risk (RR) for HLA-B27+/HLA-B60- was 152 (95% CI 91 to 255) and it increased to 201 (95% CI 85 to 475) in HLA-B27+/HLA-B60+ patients (with HLA-B27-/HLA-B60- as reference). Combinational analysis of two risk factors (HLA-B27+/HLA-B60+) showed a relative excess risk due to interaction (RERI) of 46.79 (95% CI: -117.58 to 211.16), attributable proportion (AP) of 0.23 (95% CI: -0.41 to 0.88) and a synergy index (S) of 1.31 (95% CI: 0.56 to 3.04). Conclusion In conclusion, genetic interaction analysis revealed that the interaction between HLA-B60 and HLA-B27 is a better marker for the risk of AS susceptibility in a Taiwanese population.
A new liquid refractive index sensor using double-sided polishing long-period fiber gratings (DSP-LPFG) is presented. The influence of residual cladding thickness on the sensitivity of measuring ...liquid refractive index is investigated. The proposed sensor response to external liquid refractive indices varying in the range of n=1.330 − 1.375 has been carried out by measuring the transmission wavelength changes. Experimental results show that well-controlled polishing parameters can significantly increase the sensitivity. The sensitivity of −143.396 nm/RIU can be obtained in this study.
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