Disease-Causing Mutation in Extracellular and Intracellular Domain of FGFR1 Protein: Computational Approach

In-depth computationally based structural analysis of human fibroblast growth factor type 1 (FGFR1) protein carrying disease-causing mutation was performed in this study. Gain or loss of function due to missense mutations in FGFR1 is responsible for a variety of disorders including Kallmann syndrome, Apert syndrome, Pfeiffer syndrome, Crouzon syndrome, etc. The mutant model of the human FGFR1 protein was subjected to various in silico analysis, and most deleterious SNPs were screened out. Furthermore, docking and long molecular dynamics simulations were carried out with an intention of studying the possible impact of these mutations on the protein structure and hence its function. Analysis of various structural properties—especially of those of the functionally important regions: the extracellular immunoglobulin domain and intracellular Tyrosine kinase domain—gave some insights into the possible structural characteristics of the disease mutant and the wild-type forms of the protein. In a nutshell, compared to the wild-type protein, the mutant structures V273M and S685F are associated with significant changes, and the functionally important regions seem to adopt such structures that are not conducive for the wild-type-like functionality.     

Sol–gel synthesis and optical behavior of Mg–Ce–O nano-crystallites

The Mg–Ce–O powder are shown to contain periclase-type MgO and/or fluoride-type cerium oxide (CeO₂) depending upon the composition (x) defined by Ce/(Ce + Mg) atomic ratio. Lattice contraction of pariclase phase of MgO (average crystallite size ~8.8 nm) at Ce content of ‘x’ = 0.20 in comparison to pure MgO (crystallite size ~9.5 nm) has been realized due to oxygen vacancy formation. The optical band gap values of CeO₂ varies (3.0–3.2 eV) due to oxygen vacancy formation in CeO₂ phase, crystallite size and/or Ce³⁺/Ce⁴⁺ ratio. Further, the addition of Ce has shown to reduce the physisorption and chemisorption of water significantly as reflected by (1) suppression of related absorption peaks and (2) absence of magnesium hydroxide, Mg(OH)₂, bands in Fourier transform infrared spectra.     

Trash GGBFS-based geopolymer as a novel sunlight-responsive photocatalyst for dye discolouration

In this study, we report a waste material-ground granulated blast furnace slag (GGBFS) as a low cost geopolymer, hybridised with ZnO to form a novel and efficient photocatalyst capable of discolouring textile wastewater. GGBFS is a waste material in an iron industry. Methylene blue was used as the probe dye and natural sunlight was used for activation of the photocatalyst. It was observed that under the experimental conditions, ZnGP-40 exhibited twice the discoloration efficiency than conventionally used ZnO or TiO₂. This enhanced performance is majorly attributed to increased surface area of ZnO when strewn in the GGBFS matrix. The photocatalysts were characterized by SEM, TEM, PSA, TGA, BET and UV–Vis/NIR. The effect of photocatalyst loading, speed of agitation and solar insolation has also been studied. Since this study has been performed in direct sunlight, it exhibits a realizable application of solar energy in the treatment of wastewater.     

Approaches for Mitigating Microbial Biofilm-Related Drug Resistance: A Focus on Micro- and Nanotechnologies

Biofilms play an essential role in chronic and healthcare-associated infections and are more resistant to antimicrobials compared to their planktonic counterparts due to their (1) physiological state, (2) cell density, (3) quorum sensing abilities, (4) presence of extracellular matrix, (5) upregulation of drug efflux pumps, (6) point mutation and overexpression of resistance genes, and (7) presence of persister cells. The genes involved and their implications in antimicrobial resistance are well defined for bacterial biofilms but are understudied in fungal biofilms. Potential therapeutics for biofilm mitigation that have been reported include (1) antimicrobial photodynamic therapy, (2) antimicrobial lock therapy, (3) antimicrobial peptides, (4) electrical methods, and (5) antimicrobial coatings. These approaches exhibit promising characteristics for addressing the impending crisis of antimicrobial resistance (AMR). Recently, advances in the micro- and nanotechnology field have propelled the development of novel biomaterials and approaches to combat biofilms either independently, in combination or as antimicrobial delivery systems. In this review, we will summarize the general principles of clinically important microbial biofilm formation with a focus on fungal biofilms. We will delve into the details of some novel micro- and nanotechnology approaches that have been developed to combat biofilms and the possibility of utilizing them in a clinical setting.     

Importance of van der Waals interaction for organic molecule-metal junctions: adsorption of thiophene on Cu(110) as a prototype

We report ab initio calculations for the interface energetics of a weakly adsorbed organic molecule on a metal surface, which serves as a model interface relevant for organic electronics. The studied thiophene ring is found to be physisorbed on the Cu(110) surface with an adsorption energy of -0.50 eV. Nonlocal correlations, i.e., van der Waals interactions, are solely responsible for the binding in this weakly interacting system, and the choice of the proper exchange-correlation function is crucially important. The adsorption of thiophene lowers the metal work function due to the formation of surface dipoles while no sizable charge transfer is found.     

Approximation of functions of Lipschitz class and solution of Fokker-Planck equation by two-dimensional Legendre wavelet operational matrix

In this paper, Lipschitz class of two-variables is considered. This is the genralization of well-known Lipschitz class of functions. A new estimator of functions belonging to generalized Lipschitz class has been obtained. Also, the solutions for the Fokker-Planck equations have been obtained for two different cases by two-dimensional Legendre wavelet operational matrix method. The approximated solutions of the time-and space-Fokker Planck equation have been compared with the exact solutions and the solutions obtained by homotopy perturbation method. The proposed scheme is simple, effective and suitable for the solution of Fokker-Planck equation.

     

Reaction of OH radical and ozone with methyl salicylate – a DFT study

A theoretical study on the reaction mechanism of methyl salicylate (MeSA), a green leaf volatile organic compound with OH radical and ozone, has been carried out using density functional theory methods using B3LYP, M06‐2X and MPW1K functionals with 6‐311++G(d,p) basis set. The atmospheric degradation pathways of MeSA with OH radical are studied under two different pathways, viz. H‐atom abstraction and electrophilic addition of OH radical. The hydrogen abstraction from –OH group is found to be the dominant reaction channel with small barrier height. Likewise, the electrophilic addition of OH radicals at the para position of MeSA is found to be favourable rather than the ortho and meta positions because of the small barrier height. However, the reaction of MeSA with respect to the addition of O₃ is initiated only through the cycloaddition to the C?C bond, resulting in primary ozonide. The Arrhenius plot for most of the addition reaction shows positive temperature dependence, while for the abstraction reaction, it exhibits negative temperature dependence over the temperature range of 278–350 K. The calculated theoretical rate constants are in good agreement with available experimental data. Overall, the addition of both OH radical and ozone possesses ability to degrade MeSA, but slower when compared with the Cl radical. Copyright © 2015 John Wiley & Sons, Ltd.     

Analysis and Characterization of Microwave Irradiation–Induced Graft Copolymerization of Methyl Methacrylate onto Delignified Grewia Optiva Fiber

Grafting of methyl methacrylate (MMA) onto delignified Grewia optiva fiber using ascorbic acid/H₂O₂ as an initiator was carried out under microwave irradiation. The effects of varying the microwave power, exposure time, and concentration of initiator and monomer of graft polymerization were studied to obtain maximum grafting percentage (26.54%). The experimental results showed that the optimal conditions for grafting were: exposure time, 10min; microwave power, 110 W; ascorbic acid concentration, 3.74mol/L × 10^?2; H₂O₂ concentration, 0.97mol/L × 10^?1; monomer concentration, 1.87mol/L × 10^?1. The graft copolymers were characterized by Fourier transform-infrared (FT-IR) spectroscopy, scanning electron microscopy (SEM), and thermogravimetric analysis (TGA).     

Fabrication of flexible conducting thin films of copper-MWCNT from multi-component aqueous suspension by electrodeposition

Flexible thin films of metal–carbon nanotube (CNT) with densely populated CNT morphology were fabricated by electrodeposition from an optimized copper bath. The substrate used for the present work is polyethylene film that was pre-deposited with electroless copper as a seed layer before CNT deposition. Optimum concentration of CNT was incorporated into copper bath and the electrodeposition was done at quiescent and agitation conditions. The bonding between the seed layer and the electrodeposited copper was good as revealed from adhesion test. Electrical as well as physical-mechanical property of the film was improved by CNT incorporation within the metal matrix. The topography and the texture of the metal–CNT deposit showed a well-refined structure as per scanning electron microscope (SEM), field emission scanning electron microscope (FE-SEM), and scanning probe microscope (SPM) analysis. The stability of the film was tested by cyclic voltammetric and stripping analysis under various applied conditions. Raman spectra and Fourier transfer infrared spectroscopic (FT-IR) analysis revealed the presence of CNT and the functionality of CNT within the copper matrix. Transmission electron microscope (TEM) analysis showed nucleation of copper on the surface of CNT walls.