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Till date it is a great challenge to synthesize CdS photocatalyst with a high stability. In this study, a stable CdS photocatalyst was successfully synthesized by a simple, cost‐effective hydrothermal route via cadmium acetate and thiourea as Cd and S precursors, respectively. The effect of different processing times (8 h and 24 h) and molar ratios on the photocatalytic activity and stability were mainly investigated. The samples were characterized in detail by XRD, FT‐IR, XPS, UV‐vis DRS, Photolummiscence spectroscopy and Surface photovoltage. The photocatalytic activity of the as‐obtained nanostructures was examined for methylene blue (MB) dye degradation under visible light irradiation (λ≥420 nm). After 70 min of irradiation, nearly 82 % of MB was degraded by CdS nanostructures, display an improved photocatalytic activity for MB degradation with an apparent rate constant (k) of 0.019 min−1. Additionally, CdS nanostructures sustained a good photostability after five consecutive cycles. The higher photocatalytic activity of CdS nanostructure is attributed to an efficient separation of photogenerated electron‐hole pairs stimulated by its optimal molar ratio, optimal temperature and surface morphology. Our synthesized stable nanostructures have potential for dye contaminated waste‐water treatment. [ABSTRACT FROM AUTHOR]

This study aims to compare the methylene blue (MB) removal capacity from aqueous solutions of seven natural Date Palm (Phoenix dactylifera L.) By‐products (DPBPS). These include: Leaflets (DPLL), Rachis of leaf (DPRL), Fruit Bunch Stalk (DPFBS), Empty Fruit Bunch (DPEFB), Leaf Base (DPLB), fibrillium (DPF) and Spathe Sheath (DPSS), obtained from three different date palm cultivars: Degla, Ghers and Takermost from Ouargla Oasis in the Algerian Sahara, and to investigate the influence of the palm date nature part and cultivar on MB adsorption. Batch adsorption experiments were conducted at different concentrations; 30, 45, 60, 75, 90, and 105 mg/L of MB with 2.5 g of DPBP of each cultivar. The DPBPS of all cultivars exhibits remarkable adsorption efficiencies for MB removal. The highest maximal experimental adsorption capacities were observed for Degla DPLB (4.192 mg/g), Ghers DPF (4.191 mg/g) and Takermost DPF (4.193 mg/g) with(99.81 %), (99.79 %), and (99.82 %) adsorption rates in their cultivar respectively. Conversely, the lowest maximal experimental adsorption capacities were found for Degla DPLL 4.048 mg/g, Ghers DPEFB (4.12 mg/g) and Takermost DPSS (4.089 mg/g) with 96.40 %, 98.09 %, and at 97.67 % adsorption rates in each cultivar respectively. The equilibrium adsorption data were analyzed using Langmuir and Freundlich models. The results indicated a good fit with the Freundlich model. The studied DPBPS represent natural, low‐cost, and locally available adsorbents that effectively remove MB from wastewater. [ABSTRACT FROM AUTHOR]

The ability of heterogeneous photocatalysis to effectively remove organic pollutants from wastewater has shown great promise as a tool for environmental remediation. Pure zinc ferrites (ZnFe2O4) and magnesium‐doped zinc ferrites (Mg@ZnFe2O4) with variable percentages of Mg (0.5, 1, 3, 5, 7, and 9 mol%) were synthesized via hydrothermal route and their photocatalytic activity was checked against methylene blue (MB) taken as a model dye. FTIR, XPS, BET, PL, XRD, TEM, and UV‐Vis spectroscopy were used for the identification and morphological characterization of the prepared nanoparticles (NPs) and nanocomposites (NCs). The 7% Mg@ZnFe2O4 NPs demonstrated excellent degradation against MB under sunlight. The 7% Mg@ZnFe2O4 NPs were integrated with diverse contents (10, 50, 30, and 70 wt.%) of S@g‐C3N4 to develop NCs with better activity. When the NCs were tested to degrade MB dye, it was revealed that the 7%Mg@ZnFe2O4/S@g‐C3N4 NCs were more effective at utilizing solar energy than the other NPs and NCs. The synergistic effect of the interface formed between Mg@ZnFe2O4 and S@g‐C3N4 was primarily responsible for the boosted photocatalytic capability of the NCs. The fabricated NCs may function as an effective new photocatalyst to remove organic dyes from wastewater. [ABSTRACT FROM AUTHOR]

Ferroptosis is expected to be a therapeutic target for cancers including pancreatic cancer. We aimed to screen genes that regulate ferroptosis and doxycycline resistance in pancreatic cancer and to explore the underlying mechanisms. Bioinformatics analysis was performed to identify genes that respond to ferroptosis in two human pancreatic cancer cells with GOT1 knocked down or not. 325 and 842 genes were upregulated in MiaPaCa and Tu8902 cells in response to GOT1 knockdown, with 43 genes shared. Among the 43 genes, 14 genes were identified to interact with ferroptosis key genes. MB and HMOX1 were the genes most sensitive to Erastin and doxycycline. Moreover, MB and HMOX1 expression was higher in human normal pancreatic duct epithelial cells than in pancreatic cancer cells. MB and HMOX1 proteins physically bound and promoted each other's expression. By interacting with HMOX1, MB suppressed pancreatic cancer cell proliferation, colony formation and invasion, and promoted cell ferroptosis and sensitivity to erastin and doxycycline. Silencing HMOX1 reversed the promoting effect of MB on cell ferroptosis and sensitivity to doxycycline. A pancreatic cancer xenograft model was established by subcutaneous injection of Panc‐1 cells transfected with or without Ad‐MB, and doxycycline was administered intraperitoneally. Overexpression of MB enhanced the inhibitory effect of doxycycline on xenograft growth. In conclusion, MB facilitated doxycycline sensitivity in pancreatic cancer cells through promoting HMOX1‐mediated ferroptosis. [ABSTRACT FROM AUTHOR]

Morphology of photocatalyst has attracted many attentions due to its significant effect on photocatalytic properties. Herein, the effects of hydrothermal reaction conditions including time, temperature, and pH value on the morphology evolution as well as on the photocatalytic performance of SrMoO4 were investigated in detail. It was found that SrMoO4 had self‐assembled dual morphologies (spherical and dumbbell shape) under the specific reaction conditions with time=24 h, temperature=200 °C, and pH=6.13. In order to enhance its photocatalysis further, the silver nanoparticles (Ag‐NPs) were well‐dispersed uniform on the surface of as‐prepared samples to obtain Ag‐NPs/SrMoO4 composites by photoreduction method. It was determined that 3 %Ag‐NPs/SrMoO4 had the first‐class photocatalytic performance (η=83.7 %, kapp=0.05229 min‐1) for the photodegradation of MB dye, which is ∼2.52 times that of the bare SrMoO4 with dual morphology (η=51.9 %, kapp=0.02078 min−1) by comparison with the apparent first‐order reaction rate constants. The photocatalytic performance was promoted by high efficiency of photo‐induced carriers' separation based on the effect of Localized Surface Plasmon Resonance (LSPR) of well‐dispersed Ag‐NPs. [ABSTRACT FROM AUTHOR]

Owing to the great harm that water pollution has caused to the natural environment, the effective treatment of sewage is crucial. In this study, Sm‐TiO2/g‐C3N4 composites were synthesized for the degradation of MB and TC pollutants. The experimental results showed that up to 91.8% and 93.3% of MB and TC pollutants were removed within 120 min of illumination, which were 2.8 and 2.3 times greater than that of pure TiO2, respectively, showing the good optical properties of the composites. Due to the coupling between Sm‐TiO2 and g‐C3N4, the separation of photogenerated electron holes is accelerated, thereby enhancing the photocatalytic activity of the composites. This not only enabled the strong redox ability of TiO2 to be retained, but also effectively promoted electron migration, thus improving the photocatalytic activity of the composites. [ABSTRACT FROM AUTHOR]

Time‐course model‐based network meta‐analysis (MBNMA) has been proposed as a framework to combine treatment comparisons from a network of randomized controlled trials reporting outcomes at multiple time‐points. This can explain heterogeneity/inconsistency that arises by pooling studies with different follow‐up times and allow inclusion of studies from earlier in drug development. The aim of this study is to explore using simulation: (a) how MBNMA model parameters are affected by the quantity/location of observed time‐points across studies/comparisons, (b) how reliably an appropriate MBNMA model can be identified, (c) the robustness of model estimates and predictions under different dataset characteristics. Our results indicate that model parameters for a given treatment comparison are estimated with low mean bias even when no direct evidence was available, provided there was sufficient indirect evidence to estimate the time‐course. A staged model selection strategy that selects time‐course function, then heterogeneity, then covariance structure, identified the true model most reliably and efficiently. Predictions and parameter estimates from selected models had low mean bias even in the presence of high heterogeneity/correlation between time‐points. However, failure to properly account for heterogeneity/correlation could lead to high error in precision of the estimates. Time‐course MBNMA provides a statistically robust framework for synthesizing direct and indirect evidence to estimate relative effects and predicted mean responses whilst accounting for time‐course and incorporating correlation and heterogeneity. This supports the use of MBNMA in evidence synthesis, particularly when additional studies are available with follow‐up times that would otherwise prohibit their inclusion by conventional meta‐analysis. [ABSTRACT FROM AUTHOR]

Abstract: Ag nanoparticles having different size and coverage are grown on large area glass substrate (~10 cm2) using low cost successive ionic layer adsorption and reduction (SILAR) method. The SILAR parameters, such as reduction time and growth cycles are optimized to grow Ag nanoparticles with appropriate size and coverage showing maximum surface enhanced Raman scattering (SERS) enhancement of Rhodamine 6 G(R6G). For fixed growth cycles, the size and the coverage of the grown Ag nanoparticles are found to increase with the reduction time and then saturate. The size and coverage of the grown Ag nanoparticles monotonically increase with growth cycles. However, for higher growth cycles, the shape of Ag nanoparticles could not maintain their sphericity and became rock shaped/nonspherical particles, giving rise to intense quadruple plasmon resonance. The growth mechanism is proposed. Further, SERS activity of the grown Ag nanoparticles is studied for an industrial pollutant methylene blue (MB). The observed SERS enhancement factor (~109) for MB is much higher than the reported values in literature. Measured relative standard deviations values of Ag nanoparticles grown with optimum SILAR parameters suggest the excellent homogeneity and reproducibility of the SERS signal. [ABSTRACT FROM AUTHOR]

ABSTRACT The present work describes the synthesis of hydroxyapatite-lambda carrageenan CaHAp-(λ-Carr) using an aqueous co-precipitation method. The characterization of the prepared hybrid compounds was achieved using chemical analysis, Fourier Transform Infrared spectroscopy, powder X-ray diffraction, scanning electron microscopy, and specific surface area. The results gleaned from X-ray powder analysis proved the presence of (λ-Carr) and revealed that the increase of its concentration leads to the decrease of the CaHAp crystallinity. Fourier transform Infrared spectra show the presence of (λ-Carr) and CaHAp characteristic vibrations in the resulting product. Scanning electron microscopy analyses reveal that the morphology of particles was changed by grafting and they are characterized by aggregates of different sizes and irregular shapes. After grafting BET measurements yielded particle specific surface areas ranging from 93 to 260 m2 g−1 depending on the grafted biopolymer. The prepared products were, further, applied for the adsorption of methylene blue (a cationic dye) from aqueous suspension. The adsorption capacity was determined with respect to pH value, the initial dye concentration, time contact, and temperature. The kinetic, thermodynamic, and adsorption isotherm models were assessed for the description of the dye adsorption process. The experimental resulting data show that the prepared hybrid compound CaHAp-(λ-Carr) is an efficient adsorbent for the removal of dyes. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 45385. [ABSTRACT FROM AUTHOR]

Purpose Cardiac MRI at 7T suffers from contrast heterogeneity that can be mitigated with parallel transmission (pTX) and, when performed during breath-hold, from a limited number of slices that can be multiplied with multiband (MB) radiofrequency pulses by simultaneous excitation of multiple slices (SMS). The goal of this study was to apply both approaches simultaneously. Methods Using a 16-channel transmit/receive body coil, pTX SMS was applied with/without CAIPIRINHA with a modified gradient echo cine sequence. Different calibration schemes were investigated for the slice-GRAPPA reconstruction kernels as a function of the cardiac cycle. Results Excellent slice separation for MB = 2 was achieved with CAIPIRINHA, with slice leakage values below 3% for 99% of all voxels. A critical finding of this study was the variation of the MB leakage factor in the heart by as much as 30% throughout the cardiac cycle, which was reduced greatly when reconstruction kernels were calibrated on multiple cardiac phases. Acceptable results were still obtained when applying further acceleration with MB = 3 in combination with in-plane GRAPPA. In one case, two-spoke pulses were compared with one-spoke pulses, resulting as expected in improved homogeneity. Conclusion pTX SMS imaging at 7T can address contrast heterogeneity while allowing larger slice coverage in cardiac MRI performed under breath-hold. Magn Reson Med 77:1010-1020, 2017. © 2016 International Society for Magnetic Resonance in Medicine [ABSTRACT FROM AUTHOR]

Metalloproteins are a category of biomolecules in which the metal site is usually the locus of activity or function. In many cases, the metal ions are paramagnetic or have accessible paramagnetic states, many of which can be studied using NMR spectroscopy. Extracting useful information from 1H NMR spectra of highly paramagnetic proteins can be difficult because the paramagnetism leads to large resonance shifts (~400 ppm), extremely broad lines, extreme baseline nonlinearity, and peak shape distortion. It is demonstrated that employing polychromatic and adiabatic shaped pulses in simple pulse sequences, then combining existing sequences, leads to significant spectral improvement for highly paramagnetic proteins. These sequences employ existing technology, with available hardware, and are of short duration to accommodate short nuclear T1 and T2. They are shown to display uniform excitation over large spectral widths (~75 kHz), accommodate high repetition rates, produce flat baselines over 75 kHz while maintaining peak shape fidelity, and can be used to reduce spectral dynamic range. High-spin ( S = 5/2) metmyoglobin, a prototypical highly paramagnetic protein, was used as the test molecule. The resulting one-dimensional (1D) pulse sequences combine shaped pulses with super-water elimination Fourier transform, which can be further combined with paramagnetic spectroscopy to give shaped pulses with super-water elimination Fourier transform-paramagnetic spectroscopy. These sequences require, at most, direct current offset correction and minimal phasing. The performance of these sequences in simple 1H 1D, 1D NOE, and two-dimensional NOESY experiments is demonstrated for metmyoglobin and Paracoccus denitrificans Co2+-amicyanin ( S = 3/2), and employed to make new heme hyperfine resonance assignments for high-spin met BjFixLH151-256, the heme sensing domain of Bradyrhizobium japonicum FixL. Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

SUMMARY During the real-time video transmission over error-prone network, the compressed video signal is very sensitive to the channel disturbances, and the packet loss cannot be avoided which causes the video quality reduction in the destination. To satisfy the audiences' visual feeling, the decoder attempts to conceal the error effect by using the spatial or temporal domain information to estimate the missing video content. In this paper, an efficient temporal error concealment (ETEC) algorithm is proposed for H.264/AVC Inter frame decoding to eliminate the error effect for Human Visual System (HVS). The 4 × 4 block size is used as the basic motion vector (MV) recovery unit to increase the error concealment (EC) accuracy, and the MV of the lost macroblock (MB) is recovered by employing the MV information of the neighboring intact MBs based on the geometry and data interpolation. The simulation results show that the proposed algorithm can achieve better performance compared with the existing TEC methods not only for the objective quality measurement, but also for the HVS subjective view perception. Because of its simple composition, the proposed algorithm is pervasive to be used in the real-time multimedia communication systems with the video coding standard H.264/AVC. Copyright © 2011 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The porous hybrid carbon and carbon nitride composites (C/CN‐P123‐x) with higher adsorption capacity and improved photocatalytic activity for methylene blue (MB) degradation were obtained using partially formaldehyde‐modified dicyandiamide and amphiphilic block polymers (P123) as precursor and soft‐template, respectively. The structures of as‐prepared composites were analyzed by thermogravimetric analysis, X‐ray diffraction, elemental analysis, nitrogen adsorption–desorption, scanning electron microscopy, transmission electron microscopy, photoluminescence spectroscopy, and X‐ray photoelectron spectroscopy. The effect of carbon content on the structure of the composites and the catalytic activity for the photodegradation of MB were determined under visible light. The optimal carbon content is determined to be 27.17 wt % on the C/CN‐P123‐0.8 with MB photodegradation rate of 0.0115 min−1, which was 1.92 times higher than that of C/CN‐P123‐0. The remarkably increased photocatalytic performance arises from the synergistic effect of hybrid carbon and graphitic carbon nitride. Also, the possible degradation mechanism of C/CN‐P123‐0.8 for MB was proposed. © 2019 American Institute of Chemical Engineers Environ Prog, 38:e13146, 2019 [ABSTRACT FROM AUTHOR]

An efficient intra coding method is presented for depth coding, namely edge skip. In the proposed method, the depth edge macro‐block (MB) is skipped without coding. At the decoder side, the edge MB is reconstructed with the reference samples of the adjacent left and above lines, and the associated partitioning information. The partitioning information is derived from the co‐located area in the corresponding reconstructed texture image by a k‐means clustering. Experimental results demonstrate that the proposed method significantly improves the coding efficiency both objectively and subjectively. [ABSTRACT FROM AUTHOR]

An efficient distortion‐correcting algorithm for the intra‐coding of a depth map is presented by considering the property of the flat area in a depth map. The influence of the distortion of reference pixels on the rate‐distortion (RD) cost function of the macro‐block (MB) in a flat region of a depth map is analysed. Then, the RD performance of the flat region is improved by correcting the distortion of the first MB in the flat area on the basis of this analysis. Experiments show that the performance of the synthesis view of the proposed method can achieve average peak signal‐to‐noise ratio (PSNR) of 0.32 and 0.30 dB compared with the JMVC8.5 and the plane segmentation‐based intra‐prediction method, respectively. [ABSTRACT FROM AUTHOR]