Tetraphenylethene Derivatives Modulate the RNA Hairpin-G-Quadruplex Conformational Equilibria in Proto-oncogenes**

RNA G-quadruplex (GQs) sequences in 5′-UTRs of certain proto-oncogenes co-localize with hairpin (Hp) forming sequences resulting in intramolecular Hp-GQ conformational equilibria, which is suggested to regulate cancer development and progression. Thus, regulation of Hp-GQ equilibria with small molecules is an attractive but less explored therapeutic approach. Herein, two tetraphenylethene (TPE) derivatives, TPE−Py and TPE-MePy, were synthesized and their effect on Hp-GQ equilibrium was explored. FRET, CD and molecular docking experiments suggest that cationic TPE-MePy shifts the Hp-GQ equilibrium significantly towards the GQ conformer mainly through π-π stacking and van der Waals interactions. In the presence of TPE-MePy, the observed rate constant values for first and second folding steps were increased up to 14.6 and 2.6-fold, respectively. The FRET melting assay showed a strong stabilizing ability of TPE-MePy (ΔTm=4.36 °C). Notably, the unmethylated derivative TPE−Py did not alter the Hp-GQ equilibrium. Subsequently, luciferase assay analysis demonstrated that the TPE-MePy derivatives suppressed the translation efficiency by ∼5.7-fold by shifting the Hp-GQ equilibrium toward GQ conformers in the 5’-UTR of TRF2. Our data suggests that HpGQ equilibria could be selectively targeted with small molecules to modulate translation for therapy.     

Development of CdS based stable thin film photo electrochemical solar cells

CdS semiconductor films have been prepared from chemical bath deposition from basic solutions. Electron microscopic studies have revealed the presence of polycrystalline mixed cubic and hexagonal phases of CdS in the deposits. When surface treated, these layers show good photo electro chemical behaviour in Ti/CdS/S/C cell configuration where as photo etching improves the stability of CdS photo anode in polysulphide electrolyte to a great extent. Optical absorption studies of these films have been carried out in the wavelength range 350–800 nm.     

Physical and thermal behaviour of Sr-La-Al-B-Si based SOFC glass sealants as function of SrO content and B2O3/SiO2 ratio in the matrix

A series of SOFC glass sealants with composition SrO (x), La₂O₃ (15), Al₂O₃ (15), B₂O₃ (40 − x), and SiO₂ (30) [x = 10, 15, 20, 25 and 30] (wt.%) [SLABS] are investigated for their structure property correlations at different compositions. Quantitative Fourier transform infrared spectroscopy shows structural rigidity with increasing SrO content, as demonstrate by an increase in the Si-O-Si/O-Si-O bending and B-O-B stretching frequencies. The role of SrO as a modifier dominates the control of the structure and behaviour of glasses compared with the effect of network formers, i.e., the B₂O₃/SiO₂ ratio. Consequent to the structural changes, increasing substitution of B₂O₃ by SrO the glasses causes increases in the density, glass transition temperature and dilatometric softening point. On the other hand, the crystallization temperatures show a decreasing trend and the coefficient of thermal expansion increases with increase in substitution.     

Investigation of crystallization kinetic of SrO-La2O3-Al2O3-B2O3-SiO2 glass and its suitability for SOFC sealant

Strontium-lanthanum-aluminoborosilicate (SrO-La₂O₃-Al₂O₃-B₂O₃-SiO₂) (SLABS) glass was prepared for sealant material in planar Solid Oxide Fuel Cells (pSOFC). Differential Thermal Analysis of the glass showed the formation of two crystalline phases, first one 807 °C and the second phase at 1021 °C. Crystallization kinetic of the first crystalline phase was investigated by differential thermal analysis (DTA) and using the JMA-kinetic model. The activation energy for crystallization was calculated to be 114.04 kJ/mol with frequency factor 5.9 × 10³. Coefficient of Thermal Expansion (CTE) of the glass was measured to be 9.72 × 10⁻⁶/°C. Optical band gap of the glass was measured to be 3.07 eV. Conductivity measured by Impedance spectroscopy found to be 5.68 × 10⁻⁷ S cm⁻¹ at 600 °C and it increased with temperature to 2.68 × 10⁻⁶ S cm⁻¹ at 800 °C. Activation energy for electrical conduction was measured to be 66.12 kJ/mol. Wetting behavior of the glass on a ferritic steel substrate was investigated under hot stage microscopy. It showed initial deformation temperature (IDT) 754 °C, softening temperature (ST) 840 °C, hemispherical temperature (HT) 1108 °C and flow temperature (FT) 1279 °C.     

Effect of camel milk protein hydrolysates against hyperglycemia,hyperlipidemia, and associated oxidative stress in streptozotocin (STZ)-induced diabetic rats

This study investigated the effect of camel milk protein hydrolysates (CMPH) at 100, 500 and 1,000 mg/kg of body weight (BW) for 8 wk on hyperglycemia, hyperlipidemia, and associated oxidative stress in streptozotocin-induced diabetic rats. Body weights and fasting blood glucose levels were observed after every week until 8 wk, and oral glucose tolerance test (OGTT) levels and biochemical parameters were evaluated after 8 wk in blood and serum samples. Antioxidant enzyme activity and lipid peroxidation in the liver were estimated, and histological examination of the liver and pancreatic tissues was also conducted. Results showed that CMPH at 500 mg/kg of BW [camel milk protein hydrolysate, mid-level dosage (CMPH-M)] exhibited potent hypoglycemic activity, as shown in the reduction in fasting blood glucose and OGTT levels. The hypolipidemic effect of CMPH was indicated by normalization of serum lipid levels. Significant improvement in activity of superoxide dismutase and catalase, and reduced glutathione levels were observed, along with the attenuation of malondialdehyde content in groups fed CMPH, especially CMPH-M, was observed. Decreased levels of liver function enzymes (aspartate aminotransferase and alanine aminotransferase) in the CMPH-M group was also noted. Histology of liver and pancreatic tissue displayed absence of lipid accumulation in hepatocytes and preservation of β-cells in the CMPH-M group compared with the diabetic control group. This is the first study to report anti-hyperglycemic and anti-hyperlipidemic effect of CMPH in an animal model system. This study indicates that CMPH can be suggested for its therapeutic benefits for hyperglycemia and hyperlipidemia, thus validating its use for better management of diabetes and associated comorbidities.     

Effect of processing techniques on the mechanical and wear properties of Al-20Si alloy

In the present investigation, the mechanical and wear properties of Al-20Si alloy processed by spray casting and vertical centrifugal casting processes have been evaluated and compared. In spray casting process the melt was gas atomized and the spray-deposited over a copper substrate. The spray-deposit exhibited considerable porosity and subjected to hot isostatic pressing to reduce the porosity from 19 to 2%. The centrifugal casting process provided cylindrical shaped preform with characteristically low porosity. The microstructure of spray cast alloy showed ultra fine and uniformly distributed primary and eutectic Si particles in the Al matrix. In contrast, a coarse polyhedral shaped morphology of the primary Si phase was observed in the microstructure of the centrifugal cast alloy. The wear rate of spray cast alloy was invariably lower than that of centrifugal cast alloy. The room temperature tensile and hardness tests of spray cast alloy showed considerable improvement in its strength, ductility and hardness over that of centrifugal cast alloy. The improvement in wear properties of spray cast alloy is discussed in the light of its microstructural modification induced by spray casting and nature of debris particles generated during wear testing.     

Breakthrough Curves and Simulation of Virus Transport through Fractured Porous Media

In this paper, an advective dispersive virus transport equation, including first-order adsorption and an inactivation constant, is used for simulating the movement of viruses in fractured porous media. The implicit finite-difference numerical technique is used to solve the governing equations for viruses in the fractured porous media. In this work, the focus is (1)?to investigate the transport processes of the movement of viruses in both fractured rock and porous rock without fracture and (2)?to simulate the experimental data of biocolloids through a fractured aquifer model. It is seen that movement of the contaminant is faster in the fractured rock than in the porous rock formation. Higher values of diffusion coefficient, matrix porosity, mass transfer constant, and inactivation rate reduce both temporal and spatial virus concentrations in the fracture. Also, experimental data of biocolloids in the fractured aquifer model with constant and time-dependent inactivation rates were simulated successfully.     

Thermal and mechanical properties of polyisobutylene‐based thermoplastic polyurethanes

We investigated thermal and mechanical properties of thermoplastic polyurethanes (TPUs) with the soft segment comprising of both polyisobutylene (PIB) and poly(tetramethylene)oxide (PTMO) diols. Thermal analysis reveals that the hard segment in all the TPUs investigated is completely amorphous. Significant mixing between the hard and soft segments was also observed. By adjusting the ratio between the hard and soft segments, the mechanical properties of these TPUs were tuned over a wide range, which are comparable to conventional polyether‐based TPUs. Constant stress creep and cyclic stress hysteresis analysis suggested a strong dependence of permanent deformation on hard segment content. The melt viscosity correlation with shear rate and shear stress follows a typical non‐Newtonian behavior, showing decrease in shear viscosity with increase in shear rate. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 891‐897, 2013     

Effect of bitumen emulsion on setting, strength, soundness and moisture resistance of oxychloride cement

Addition of bitumen emulsion to the matrix has been found to improve strength and soundness of the product while decreasing the initial setting periods. Thus, bitumen emulsion as an admixture in magnesia cement is a moisture proofing and strengthening material.