Structural,vibrational, optical,photoluminescence, thermal,dielectric, and mechanical studies on zinc(tris) thiourea sulfate single crystal: A noticeable effect of organic dye

In this work, uranine-dyed zinc(tris) thiourea sulfate(ZTS) monocrystals, 26 mm×15 mm×10 mm in size, were synthesized by the solution method at ambient temperature. Their purity, crystallinity, lattice parameters, and functional modes were studied by x-ray diffraction, Fourier transform-infrared spectroscopy(FT-IR), and FT-Raman spectroscopy analyses. The sodium ion content of the crystals from the dye was confirmed by elemental analysis. The diffused reflectance spectral analysis of the dyed crystal revealed a characteristic absorption band at 490 nm attributed to the presence of the dye. The calculated band gaps of the non-dyed and dyed crystals were 4.53 and 4.57 e V, respectively. A green emission peak at ～(512 ± 4) nm was observed in the photoluminescence spectrum of the uranine-dyed crystals. A differential scanning calorimetry study confirmed that the thermal stability improved owing to the addition of the dye. Dielectric and microhardness studies were conducted to examine the significant improvements in the corresponding properties of dyed crystals. The results demonstrated the competency of the dyed ZTS crystals for applications in optoelectronic devices.     

A Moving Grid Eulerian Lagrangian Localized Adjoint Method for Solving One-Dimensional Nonlinear Advection-Diffusion-Reaction Equations

We develop a moving grid Eulerian-Lagrangian Localized Adjoint Method (ELLAM) to solve the one-dimensional nonlinear Advective-Dispersive-Reactive Equation (ADRE) that governs contaminant transfer with biological/chemical/radioactive processes. The method uses a moving grid to define the solution and test functions. Consequently, the need for spatial interpolation, which is a major issue in conventional ELLAM formulations, is avoided. We apply the developed method for variable-coefficient ADRE with different time and spatial discretizations. Numerical experiments show the strength of the developed scheme. Accurate results are obtained even when using large time steps. In the last part of this paper, ELLAM is used to simulate the nonlinear ADRE that arises for reactive subsurface transport with biodegradation.     

Selection of pH-related parameters in ion-exchange chromatography using pH-gradient operations

This work demonstrates that the type of ion-exchanger (anion or cation), the mode of operation (bind-and-elute or flow-through), and the operational pH of ion-exchange chromatography (IEX) can be selected in a fast and rational way by analytical pH-gradient IEX operations, thereby eliminating the need for pH scouting or high-throughput screening. The developed approach was applied for the selection of an IEX process for the capture of a monoclonal antibody (MAb) from hybridoma cell culture supernatant (CCS). It was found within a day that MAb can optimally be captured by bind-and-elute mode cation-exchange chromatography (CEX) at pH 4.5 or anion-exchange chromatography (AEX) at pH 7.2 without lowering the salt concentration in the CCS. The performance of both CEX and AEX was predicted to be equal for this particular MAb capture.     

Copper‐Catalyzed Perfluoroalkylthiolation of Alkynes with Perfluoroalkanesulfenamides

Copper‐catalyzed direct perfluoroalkylthiolation of alkynes by using the corresponding perfluoroalkanesulfenamide reagent is reported. The selective mono‐ and bis‐perfluoroalkylthiolation of alkynes can be conducted under very mild conditions (no base, room temperature) in very good to excellent yields. This approach, which uses a low toxicity, inexpensive copper catalyst that incorporates a commercially available ligand, is applied in the absence of any additional base. Preliminary mechanistic investigations shed some light on the nature of the unprecedented reactivity observed.     

FNDC5/Irisin: Physiology and Pathophysiology

A sedentary lifestyle or lack of physical activity increases the risk of different diseases, including obesity, diabetes, heart diseases, certain types of cancers, and some neurological diseases. Physical exercise helps improve quality of life and reduces the risk of many diseases. Irisin, a hormone induced by exercise, is a fragmented product of FNDC5 (a cell membrane protein) and acts as a linkage between muscles and other tissues. Over the past decade, it has become clear that irisin is a molecular mimic of exercise and shows various beneficial effects, such as browning of adipocytes, modulation of metabolic processes, regulation of bone metabolism, and functioning of the nervous system. Irisin has a role in carcinogenesis; numerous studies have shown its impact on migration, invasion, and proliferation of cancer cells. The receptor of irisin is not completely known; however, in some tissues it probably acts via a specific class of integrin receptors. Here, we review research from the past decade that has identified irisin as a potential therapeutic agent in the prevention or treatment of various metabolic-related and other diseases. This article delineates structural and biochemical aspects of irisin and provides an insight into the role of irisin in different pathological conditions.     

Kinetics and mechanisms of the catalyzed decomposition of hydrogen peroxide by ethylenebis(oxyethylenedinitrilo)tetracetate complex of iron(III)

The rate of decomposition of H₂O₂ in the presence of Fe(III)-y complex (y is ethylenebis(oxyethylenedinitrilo)tetraacetic acid (EGTA) anion) was investigated under variable conditions of pH and temperature, various water-miscible solvents, and different concentrations of H₂O₂, [Fe-y]⁻, and acetate ions. The following rate law holds: Rate = (k₁K₃K₄/[H⁺]) [Fe-y(OH)]²⁻ [H₂O₂] at pH less than 9.80, and Rate = (k₂K₅[H⁺]/K₃) [Fe-y(OH)₂]³⁻[OOH]⁻ at pH above 9.80. The values of k₁K₄and k₂K₅ at 25 °C were found to be 1523 and 0.747 M⁻¹ S⁻¹, respectively. Activation enthalpy and activation entropy for this reaction were determined from Arrhenius plots and found to be ΔH^* = 34.38 K J mol⁻¹ and ΔS^* = −167.2 J K⁻¹ mol⁻¹.     

Inhibitory Effect of Biosynthesized Silver Nanoparticles from Extract of <Emphasis Type="Italic">Nitzschia palea</Emphasis> Against Curli-Mediated Biofilm of <Emphasis Type="Italic">Escherichia coli</Emphasis>

Extended spectrum beta lactamase (ESBL) are emerging beta-lactamases in Gram-negative pathogens, causing serious problems in hospitalized patients worldwide. Biofilm mode of virulence has decreased the efficiency of antibiotics used for treatment against ESBL pathogens. Therefore, there is an urgent need for alternative agents such as nanoparticles that can prevent and inhibit the biofilm formation. The aim of the present study was to inhibit the biofilm formed by ESBL-producing Escherichia coli using silver nanoparticles (AgNPs) synthesized with fresh water diatom (Nitzschia palea). AgNPs were characterized using UV-Vis spectroscopy, Fourier transform infrared (FTIR) spectroscopy, field emission scanning electron microscope (FESEM), energy-dispersive X-ray spectroscopy (EDX), and XRD. AgNPs at their biofilm inhibitory concentration (BIC) of 300 ng ml^?1 significantly reduced the biofilm formed by E. coli. Interestingly, Congo red assay revealed the reduction of curli, essential for biofilm formation in the presence of AgNPs. Light and CLSM examination of the biofilm images also validated that in the presence of AgNPs, the biofilm architecture was disintegrated and the thickness was significantly reduced. Overall, the present study exemplifies the use of AgNPs as a plausible alternative for conventional coating agents on implant devices to prevent and control biofilm-associated urinary tract infections.