Albumin stimulates lysophosphatidic acid acyltransferase activity in T-lymphocyte membranes

Phosphatidic acid (PtdOH) and lysophosphatidic acid (lysoPtdOH) have been shown to enhance T-lymphocyte function. However, the FA preference and influence of acyl-CoA binding proteins on lysoPtdOH and PtdOH biosynthesis are not known. Therefore, we determined glycerol-3-phosphate acyltransferase (GPAT) and lysophosphatidic acid acyltransferase (LAT) activity in rat T-lymphocyte and liver membrane preparations in the presence of palmitoyl-CoA and oleoyl-CoA with or without BSA. We found two different properties of GPAT and LAT in whole T-lymphocyte membrane preparations relative to liver. First, T-lymphocyte basal GPAT and LAT activities were similar, whereas in liver membranes LAT activity was 10-fold higher than GPAT. Second, T-lymphocyte LAT, but not GPAT, activity was inducible (fivefold) by the addition of albumin in the presence of palmitoyl-CoA but not oleoyl-CoA. In contrast, albumin stimulated GPAT, but not LAT, activity in liver membranes in the presence of palmitoyl-CoA. These results show, for the first time, that T-lymphocyte LAT activity can be increased by the presence of an acyl-CoA binding protein, which may indicate a new important control mechanism for regulating intracellular lysoPtdOH and PtdOH levels in T-lymphocytes.     

Shear velocity-based uncertainty quantification for rock joint shear strength

Bulletin of Engineering Geology and the Environment - The shear strength of rock joints is an important property required in order to analyze the stability of rock slopes and tunnels. However,...     

Experimental Investigation on the Performance of a Solar Still Using SiO2 Nanoparticles /Jatropha curcas L

Silicon - Now, enticing systematic civic since everywhere the world is used in green synthesis and benefit of the simple is eco-friendly with an emergent method of producing nanoparticles (NPs)....     

Synthesis,microstructure and optical characterization of zirconium oxide nanostructures

Zirconium oxide (ZrO₂) nanostructures were synthesized by hydrothermal route. Surface morphology analysis depicts the formation of the nanobars and hexagonal-shaped nanodiscs at different synthesis conditions. The structural analysis confirms that the as-synthesized ZrO₂ product is of pure monoclinic phase (m-ZrO₂) with crystallite size of about 25 nm. The product consists of monodispersed nanoparticles of uniform composition, high purity, and crystallinity. The Raman spectra are quantitatively analyzed and the observed peaks are attributed to various vibration modes of the m-ZrO₂. The UV–vis absorption spectrum showed a strong absorption peak at about 292 nm and the estimated optical band gap was around 3.57 eV. Photoluminescence (PL) spectrum of ZrO₂ nanostructure showed a strong and broad emission peak at around 410 nm at room temperature, which can be attributed to the ionized oxygen vacancy in the material.     

Tuning of PEM fuel cell model parameters for prediction of steady state and dynamic performance under various operating conditions

Many models are available with various degrees of complexity to study the behaviour of Proton Exchange Membrane Fuel Cells (PEMFC) under varying operating conditions. To our knowledge no model has been developed from single cells to multiple cells with increased electrode area for PEMFC stacks along with power conditioners, by considering the dynamic characteristics of the fuel cells under the influence of stoichiometry, humidity ratio and their response during their integration with power conditioners. We have developed a model using Matlab to study the transient response of the cell for 30 cm², which has been extended to a multicell stack of 1.2 kW capacity of electrode area 150 cm². The developed model has been validated using PEMFC single cells and stacks, by considering partial pressure of hydrogen, oxygen, and water as three states, anode fuel utilization and all three losses. This model is proposed to evaluate the transient response of all the stacks developed at Centre for Fuel Cell Technology (CFCT) ranging from a few watts to 10 kW that are integrated with various power conditioners depending on the applications.     

Double emulsion‐encapsulated guggul exhibits improved in vivo hypocholesterolaemic action in rats

Guggul tree or Commiphora mukul is a small thorny herb having remarkable hypocholesterolaemic properties. Its therapeutic effects are because of its biocomponent guggulsterones, especially guggulsterone E and Z. In this research, double emulsion‐based spread was tried to improve the bioavailability of the herb guggul in in vivo rat model. The effect of the different diets with encapsulated and nonencapsulated guggul was evaluated and compared after 6 weeks, based on the final body weight and analysis of organs, serum and faeces of normal and hypercholesterolaemic (H) rats. It was evident from the results that double emulsion‐encapsulated guggul showed better control on weight of H rats (25.98% lower), inhibition of HMG CoA reductase (3.95 times less) activity and reduction in atherosclerotic index (47.2%), as compared to diet with unencapsulated guggul. Encapsulation of guggul also improved faecal excretion of bile acids, lipids and total cholesterol in H and normal rats.     

Preparation of Oil-Encapsulated Microcapsules and Tribological Property of Ni Composite Coating

Microcapsules containing oil are potential candidate materials for preparing electrocomposite coatings with excellent tribological properties. In the present study, the preparation of oil-encapsulated microcapsules and electrodeposition of Ni-microcapsule composite coating are presented along with the properties of the coating. In situ interfacial polymerization method was used for the preparation of lubricating oil-encapsulated urea-formaldehyde microcapsules. The synthesized microcapsules were incorporated into the nickel matrix by electrodeposition using Ni-Watts bath. The Ni-composite coating containing microcapsules exhibited smaller Ni grain size, higher microhardness and lower surface roughness compared to plain Ni coating. Electrodeposited Ni coating containing oil-encapsulated microcapsules exhibited improved tribological properties with lower wear loss and coefficient of friction compared to plain nickel coating.     

Solvothermal Synthesis, Structure and Optical Property of Nanosized CoSb(3) Skutterudite

Binary skutterudite CoSb₃ nanoparticles were synthesized by solvothermal method. The nanostructuring of CoSb₃ material was achieved by the inclusion of various kinds of additives. X-ray diffraction examination indicated the formation of the cubic phase of CoSb₃. Structural analysis by transmission electron microscopy analysis further confirmed the formation of crystalline CoSb₃ nanoparticles with high purity. With the assistance of additives, CoSb₃ nanoparticles with size as small as 10 nm were obtained. The effect of the nanostructure of CoSb₃ on the UV–visible absorption and luminescence was studied. The nanosized CoSb₃ skutterudite may find application in developing thermoelectric devices with better efficiency.     

Strategies for stereocontrol at C1 or C2 in syntheses of α-glucosaminides

The C1 and C2 stereocenters of α-glucosaminides can be prepared by establishing the stereocenters in either order. For the former, a C2-azido glucosyl donor is prepared first, and the restraining effect of a 4,6-O-benzylidene ring is used to induce α-coupling. For the latter, the C1 linkage is prepared first by use of an n-pentenyl-manno-1,2-orthoester donor which ensures (a) clean α-coupling and (b) a convenient C2-ester. The C2-ester is replaced with a triflate leaving group, and nucleophilic displacement is effected by use of a hypervalent silicon azide.