Creep Deformation in MgO-Saturated Large-Grain-Size Al2O3

Samples of 65 μm-grain-size AL₂O₃ containing 0.05 wt% Mg and 40 μm-grain-size AL₂O₃ containing 0.13 wt% Mg, both MgO-saturated, undergo compressive deformation in the range 1580° to 1800°C with results interpreted as diffusional creep rate-limited by grain-boundary diffusion with the Coble boundary-diffusion model giving
A lower deformation rate for an unsaturated composition indicates that MgO additions enhance grain-boundary diffusion.     

Radiometric comparison of the LANDSAT-5 TM and MSS sensors

Abstract

This paper analyses the radiometric accuracy of LANDSAT-5 Thematic Mapper (TM) data and of LANDSAT-5 Multispectral Scanner (MSS) data, using concurrent TM and MSS images recorded simultaneously over the city of Montreal, Quebec, Canada. The data sets were obtained from the Canada Centre for Remote Sensing (CCRS), and have been preprocessed for geometric correction, and for radiometric 23calibration utilizing the in-flight calibration lamp data. The comparison of the TM and MSS normalized apparent reflectances computed for 12 different typical cover types using the post-launch calibration dynamic ranges shows the relevance of the CCRS processing systems. The significant linear regressions, obtained between channels from the two sensors, and the analysis of the ground reflectance corrected for atmospheric absorption and scattering as well as for pixel adjacency effects, can serve both to assess detector degradation with time and to rescale data to match those from other LANDSAT sensors.     

Visualization and quantification of vesicle trafficking on a three-dimensional cytoskeleton network in living cells

Recent progress in biology and microscopy has made it possible to acquire multidimensional data on rapid cellular activities. Unfortunately, the data analysis needed to describe the observed biological process still remains a major bottleneck. We here present a novel method of studying membrane trafficking by monitoring vesicular structures moving along a three-dimensional cytoskeleton network. It allows the dynamics of such structures to be qualitatively and quantitatively investigated. Our tracking method uses kymogram analysis to extract the consistent part of the temporal information and to allow the meaningful representation of vesicle dynamics. A fully automatic extension of this method, together with a statistical tool for dynamic comparisons, allows the precise analysis and comparison of overall speed distributions and directions. It can handle typical complex situations, such as a dense set of vesicles moving at various velocities, fusing and dissociating with each other or with other cell compartments. The overall approach has been characterized and validated on synthetic data. We chose the Rab6A protein, a GTPase involved in the regulation of intracellular membrane trafficking, as a molecular model. The application of our method to GFP-Rab6A stable cells acquired using fast four-dimensional deconvolution video-microscopy gives considerable cellular dynamic information unreachable using other techniques.     

Measurement of Mobility and Zeta Potential of Beta-Alumina Suspensions in Various Solvents

Mobilities and zeta potentials of β -alumina particles have been measured in 1-pentanol, nitromethane, and dichloromethane media. The effects of grinding, aging, water content, and acid solute content were observed; all of these variables were critical. The charge on the β -alumina particles could be either positive or negative, depending on the suspension conditions.     

Analysis of a 35·6 kb Region on the Right Arm of Saccharomyces cerevisiae Chromosome XV

We report the sequence of a 35 600 bp fragment covering the PET123 region on the right arm of chromosome XV from Saccharomyces cerevisiae. This region contains 19 possible open reading frames (ORFs) of which 16 are non-overlapping ORFs. Eight ORFs correspond to the SPP2, SMP3, RPB2, PDR5, NFI1, PUP1, PET123 and MTR10 loci, described previously. Two ORFs correspond to yeast homologues of genes from other organisms: O3530 is a member of the large ribosomal subunit protein L13 family and O3560 (SME1 gene) is a 94-codon ORF and is a homologue of the mammalian SmE spliceosomal core protein. Three ORFs (O3513, O3521, O3548) present significant similarities to proteins of unknown function and three ORFs (O3510, O3536, O3545) lack homology to sequences within the databases screened. The sequence has been deposited in the GenBank database under Accession Number U55020. © 1997 by John Wiley & Sons, Ltd.     

Elimination of Listeria monocytogenes in soft and red smear cheeses by irradiation with low energy electrons

Soft and red smear cheeses are frequently contaminated by Listeria monocytogenes , sometimes at relatively high concentration (< 10⁵ CFUg^-1). This bacterium is radiosensitive (D₁₀ value of approximately 0.45 kGy) but irradiation of the whole cheese by X-rays induced off-flavours when the dose exceeded 1.0 kGy. Irradiation could be effective in eliminating L. monocytogenes only from lightly contaminated cheeses (> 10²CFU g^-1).
L. monocytogenes appears only in the rind (where the pH is greater than 6.3) and never grows in the core of the cheese. Under these conditions, a specific irradiation of the rind after ripening, with a low-energy electron beam at relatively high doses (up to 3.0 kGy), allows the total elimination of L. monocytogenes in heavily contaminated samples (10⁵-10⁶ CFU g^-1) without noticeable modifications of the organoleptic properties of the cheese.     

Determination of Carotenoids in Fruits of Rosa sp. (Rosa Canina and Rosa Rugosa) and of Chokeberry (Aronia Melanocarpa)

Carotenoid composition of fruits of two Rosa species (Rosa canina and Rosa rugosa) and of chokeberry (Aronia melanocarpa) was studied by high performance liquid chromatography. Nine carotenoids were determined: three carotenes (lycopene, ζ-carotene, β-carotene) and six xanthophylls (neoxanthin, trans-violaxanthin, cis-violaxan-thin, 5,6-epoxylutein, lutein, β-cryptoxanthin). This high number of compounds classified these fruits among those with the greatest variety of carotenoid pigments. Quantitatively large differences occurred in the carotenoid composition of the three fruits. Rosa hips contained the highest concentrations of total carotenoids, which were mainly comprised of lycopene and βcarotene. Conversely, total xanthophylls were low. In contrast to Rosa, fruits of Aronia were lower in total carotenoids while xanthophylls composed a higher proportion.     

A Distributed and Cooperative Environment for Computer Algebra

In this paper, we describe theCentral Control, a software component that enables several symbolic systems to cooperate and exchange data. The Central Control has been designed to be the kernel of an environment for scientific computations which can offer a common and concurrent access to several tools needed by the scientist and the engineer: general purpose and specialized computer algebra systems, visualization tools, links with numerical libraries and tools to manipulate numerical programsetc. The user can interact with the Central Control through one or more (graphical) user interfaces. The Central Control achieves its goals by requiring as little as possible from the tools and by using a particular programming language to provide a unified view for the objects and the operations performed by the connected tools. The Central Control will be used as the basis of theComprehensive Solverthat will provide common access to all the programs developed within the project. We give a simple example of an actual use of the Central Control for computing primary decompositions of ideals.