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Herein, we are reporting the enhanced electrochemical performance of hybridised WO3–CdS nanocomposites prepared by microwave assisted wet chemical route without post synthesis of heating for different wt% of CdS (2 wt%, 4 wt% and 6 wt%) loading with WO3. Then, the end products were characterized by various techniques to evaluate their structural and morphology, thermal, optical, and electrochemical properties. From the XRD analysis, the orthorhombic and monoclinic structure of WO3 and hexagonal phase of CdS were observed and the average crystalline size is calculated as ± 19 nm. The microscopic examination such as SEM images showed smooth and tiny particle and HRTEM images showed rod shape morphology in the as-prepared particle. The presence of W and Cd elements are confirmed by EDAX analysis. The existences of functional groups related to W and Cd are analyzed by FTIR investigation and confirmed the chemical bonding nature. Thermal (TGA/DTA) analysis showed that as-prepared structures are stable up to 450°C temperature. The electrochemical investigations have been carried out, and their enhanced specific capacitances were calculated as 44 F/g for pure WO3 (a) nanostructures and 48, 170, and 172 F/g correspondingly for the hybridised WO3–CdS (b, c, d) nanocomposites. [ABSTRACT FROM AUTHOR]

Tungsten oxide (WO3) nanostructures were synthesised using the microwave-assisted wet chemical method without any addition of surfactant for three different microwave irradiation times (10, 20 and 30 min). Then as-prepared nanostructures were characterised using various characterization techniques to know their structural, morphology and optical properties. The monoclinic and orthorhombic (WO3) crystal structure was obtained from the as-prepared nanostructures by using X-ray diffraction analysis and its calculated crystalline size were found to be increased from 14 to 18 nm on increasing microwave irradiation time. The functional groups were investigated by using Fourier transform infrared spectroscopy analysis and the W-O chemical bonding nature was confirmed. The surface morphology was unclear using scanning electron microscope analysis, and a careful observation in high resolution transmission electron microscope studies shows that rod shaped structure. A blue-shifted optical absorption spectrum was observed by ultraviolet-visible spectroscopy analysis analysis and the bandgap energy value of WO3 was calculated as approximately 3.62 eV. The emission behaviours were investigated by using photoluminescence spectrofluorometer analysis and an enhanced defect reduced emission was obtained. Finally, the electrochemical properties were analyzed by using cyclic voltammogram and galvanostatic charge-discharge analysis analyses. The maximum capacitance was recorded at 264 F/g which was declined to 149 F/g with the growth of WO3 nanostructures size. Hence, the effect of microwave on structure and morphology, and consequent supercapacitor performances of WO3 were discussed in details. [ABSTRACT FROM AUTHOR]

Background: Colistin-based combination therapy (CCT) is extensively used to treat infections due to carbapenem-resistant Gram-negative bacteria (CRGNB). There are no data available from India on the usefulness of combination therapy, especially in the oncology setup. The aim of this study was to analyze the clinical effectiveness of CCT over monotherapy in patients with CRGNB.Materials and Methods: We conducted a retrospective, observational study of patients with CRGNB bloodstream infections in our oncology and bone marrow transplant center.Results: Over a 3-year study period (2011-2014), we could identify 91 patients satisfying study criteria. There was no statistically significant difference in the 28-day mortality between monotherapy and combination therapy arms (mono n = 26, mortality 10 (38.5%); combination n = 65, mortality 28 (40%); P = 0.886). Neutropenic patients with Enterobacteriaceae bloodstream infections performed better with combination therapy (mono n = 7, mortality 6 (85.7%); combination therapy n = 22, mortality 8 (36.4%); P = 0.035). There was no significant difference in the 28-day mortality between the two treatment arms in other subgroups.Conclusion: Our study did not find CCT superior to colistin monotherapy in patients with CRGNB blood stream infections; except in the subgroup of neutropenic patients with Enterobacteriaceae bloodstream infections, where combination therapy performed better. [ABSTRACT FROM AUTHOR]