Topological aspects of algebras of unbounded operators

The utilization of $\text{DF}$-spaces of A. Grothendieck leads to natural topologies on 1-algebras of unbounded operators. In this way, the origin of pathologies is clarified, and natural classes of 1-algebras with good behavior are introduced. Examples and particular algebras of countable algebraic dimension are studied in the second part of the paper.     

PHOTOSTIMULATION OF AGGREGATION IN THE CELLULAR SLIME MOLD Polysphondylium violaceum

Abstract Aggregation in Polysphondylium violaceum is stimulated by light with an increase in the number of aggregates being one effect of light incubation. An aggregation-stimulating factor, D factor, has been shown previously to cause phenotypic reversal of the aggregation-defect in aggA mutants. The phenotypic reversal caused by D factor is stimulated by light. The initial time after starvation is the sensitive period for the light-stimulated increase in aggregate formation in wild type strains and also for light-stimulated sensitivity to D factor. At low light intensities both blue and green light have the greatest effect on the number of aggregates formed. However, the intensity dependence of the response is weak over the range tested (0.2 to 10 μW/cm²). Light also affects D factor causing as much as a 60-fold decrease in production and a change in the proportion of the three active components of D factor when compared to D factor produced in darkness. Light affects a decrease in D factor production when it is present during development but only significantly affects the proportions of the D factor components if present prior to aggregation.     

Parallel Newton two‐stage methods based on ILU factorizations for nonlinear systems

Parallel iterative algorithms based on the Newton method and on two of its variants, the Shamanskii method and the Chord method, for solving nonlinear systems are proposed. These algorithms are based on two‐stage multisplitting methods where incomplete LU factorizations are considered as a mean of constructing the inner splittings. Convergence properties of these parallel methods are studied for H‐matrices. Computational results of these methods on two parallel computing systems are discussed. The reported experiments show the effectiveness of these methods. Copyright © 2006 John Wiley & Sons, Ltd.     

Dosage du plutonium dans les alliages plutonium aluminium par fluorescence-x

An X-ray fluorescence method is described for the determination of plutonium in Pu-Al alloys. In order to obtain satisfactory reproducibility, the alloy is first dissolved in a nitric acid-mercury (II) nitrate mixture. The Lα emission of plutonium is measured, to eliminate matrix effects, an internal standard with a wavelength near that of the Pu emission is used. Equipment and sample preparation are described. Extension of the method to other determinations is discussed.     

The Plancherel Formula for an Inhomogeneous Vector Group

Journal of Fourier Analysis and Applications - We give a concrete realization of the Plancherel measure for a semi-direct product $$N \rtimes H$$ where N and H are vector groups for which the...     

Water-soluble pegylated quantum dots: from a composite hexagonal phase to isolated micelles

We present a simple method based on the dispersion of fluorescent quantum dots (QD) into a liquid crystal phase that provides either nanostructured material or isolated QD micelles depending on water concentration. The liquid-crystal phase was obtained by using a gallate amphiphile with a poly(ethylene glycol) chain as the polar headgroup, named I. The hydration of QD/I mixtures resulted in the formation of a composite hexagonal phase identified by small-angle X-ray scattering and by polarized light and fluorescence optical microscopy, showing a homogeneous distribution of fluorescence within hexagonal phase. This composite mesophase can be converted into isolated QD-I micelles by dilution in water. The fluorescent QD-I micelles, purified by size exclusion chromatography, are well monodisperse with a hydrodynamic diameter of 20-30 nm. Moreover, these QD do not show any nonspecific adsorption on lipid or cell membranes. By simply adjusting the water content, the PEG gallate amphiphile I provides a simple method to prepare a self-organized composite phase or pegylated water soluble QD micelles for biological applications.     

Newton additive and multiplicative Schwarz iterative methods

Daniel B. Szyld^¶ Department of Mathematics, Temple University, Philadelphia, PA 19122, USA ^{Convergence properties are presented for Newton additive andmultiplicative Schwarz (AS and MS) iterative methods for thesolution of nonlinear systems in several variables. These methodsconsist of approximate solutions of the linear Newton step usingeither AS or MS iterations, where overlap between subdomainscan be used. Restricted versions of these methods are also considered.These Schwarz methods can also be used to precondition a Krylovsubspace method for the solution of the linear Newton steps.Numerical experiments on parallel computers are presented, indicatingthe effectiveness of these methods.}