Rotating viscous-fluid cosmologies with scalar field and heat flux

Rotating cosmological models under the influence of both shear and bulk viscosity, together with scalar field and heat flow, are studied. Exact solutions of the field equations are obtained. The solutions have nonzero expansion, shear, and rotation. The properties of the solutions are studied and the temperature distribution is also given explicitly.     

Quantum chromodynamics studies at LEP2

Several studies have been made to the hadronic final states in e ⁺ e ⁻ collisions at LEP. Studies of the annihilation process at LEP2 have given rise to results on jet rate, event shape, heavy flavour production, inclusive momentum spectra, Bose-Einstein correlation and colour reconnection effects. Event shape studies have given rise to accurate determination of the strong coupling constant α _s using O (α _s ² ) with resummed leading and next-to-leading log calculation and also with power law corrections. Studies of 2-photon processes have yielded results on γγ cross-section, heavy flavour production, photon structure function and γ*γ* scattering.     

Highly redispersible sugar beet nanofibers as reinforcement in bionanocomposites

A simple method for preparing redispersible nanofibers from sugar beet residue and their use as a well-dispersed reinforcement for a polyvinyl alcohol (PVA) matrix is reported. It is known that the redispersion of dried cellulose nanofibers is difficult because of the formation of strong hydrogen bonds between the nanofibers. The results show that the properties of the initial sugar beet nanofiber suspension can be recovered without the use of chemical modification or additives with higher pectin and hemicellulose content. Undried and redispersed nanofibers with and without pectin were used as nanocomposite reinforcement with PVA. The redispersed nanofibers were as good reinforcements as the undried nanofibers. The tensile strength and elastic modulus of the nanocomposites with the redispersed sugar beet nanofibers were as good as those of the nanocomposites with undried nanofibers. Interestingly, the nanofiber dispersion in the PVA matrix was better when sugar beet nanofibers containing pectin and hemicellulose were used as reinforcements.     

A simple route to 9-fluorenylidenes by domino Suzuki/Heck coupling reactions

A palladium catalyzed domino intermolecular Suzuki followed by intramolecular Heck coupling is described. This strategy afforded a novel and convenient synthesis of various 9-fluorenylidene derivatives in one-pot under relatively mild reaction condition.     

PP2A in the regulation of cell motility and invasion

Cell motility is a very critical phenomenon that plays an important role in the development of eukaryotic organisms. One of the well studied cell motility phenomena is chemotaxis, which is described as a directional movement of cell in response to changes in external chemotactic gradient. Numerous studies conducted both in unicellular organism and in mammalian cells have demonstrated the importance of phosphatidylionositol-3 kinase (PI3K) in this process. In addition, it is now well established that although PI3K plays an activation role in chemotaxis, the role of phosphatases is also critical to maintain this dynamic cyclical process. Protein phosphatase 2A (PP2A) is a major serine/threonine phosphatase that is a key player in regulating PI3K signaling. PP2A is abundantly and ubiquitously expressed and has been highly conserved during the evolution of eukaryotes. PP2A is composed of three protein subunits, A, B, and C. Subunit 'A' is a 60-65 kDa structural component, 'C' is a 36-38 kDa catalytic subunit, and 'B' is a 54-130 kDa regulatory subunit. The core complex of PP2A is comprised of the A and C subunits, which are tightly associated and this dimeric core complexes with the regulatory B subunit. The B subunit determines the substrate specificity as well as the spatial and temporal functions of PP2A. PP2A plays an important role in regulating multiple signal transduction pathways, including cell-cycle regulation, cell-growth and development, cytoskeleton dynamics, and cell motility. This review focuses on the role of PP2A in regulating motility of normal and transformed cells.     

Franck-Condon factors and r-centroids of B-X, C-X and C-A band systems of AlO molecule

Using the high resolution Fourier transform spectrometer the B²Σ⁺-X²Σ⁺ band system of AlO molecule has been recorded. The rotational structure of eighteen bands belonging to B²Σ⁺-X²Σ⁺ transition of AlO have been analyzed which led to accurate rotational and vibrational constants of ground and excited states. A few bands, viz. (2, 1), (3, 2), (4, 3), (2, 3), (3, 4), (4, 5), and (5, 6) were analyzed for the first time. Using these constants, the Franck-Condon factors and r-centroids were computed for the bands of B-X, C-X and C-A band systems for the v′ = 0-8; v″ = 0-8 matrix using the method developed by Jarmain and Nicholls. The F-C factors and r-centroids obey the established relationships.     

Rearrangement from the heteroantiaromatic borole to the heteroaromatic azaborine motif

Treatment of 9-chloro-9-borafluorene with N,O-bis(trimethylsilyl)hydroxylamine results in 10-trimethylsilyloxy-9-aza-10-boraphenanthrene 6b. NMR spectroscopy shows that the expected antiaromatic 9-(trimethylsilyloxyamino)-9-borafluorene 5b rearranges to the formally aromatic phenanthrene 6b at room temperature.