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This work targets the emerging use of software component technology for high-performance scientific parallel and distributed computing. While component software engineering will benefit the construction of complex science applications, its use presents several challenges to performance measurement, analysis, and optimization. The performance of a component application depends on the interaction (possibly nonlinear) of the composed component set. Furthermore, a component is a ‘binary unit of composition’ and the only information users have is the interface the component provides to the outside world. A performance engineering methodology and development approach is presented to address evaluation and optimization issues in high-performance component environments. We describe a prototype implementation of a performance measurement infrastructure for the Common Component Architecture (CCA) system. A case study demonstrating the use of this technology for integrated measurement, monitoring, and optimization in CCA component-based applications is given. Copyright © 2005 John Wiley & Sons, Ltd.

Survivin is an anti-apoptotic protein that is overexpressed in most human cancers. We show that survivin forms complexes with a cellular protein, hepatitis B X-interacting protein (HBXIP), which was originally recognized for its association with the X protein of hepatitis B virus (HBX). Survivin–HBXIP complexes, but neither survivin nor HBXIP individually, bind pro-caspase-9, preventing its recruitment to Apaf1, and thereby selectively suppressing apoptosis initiated via the mitochondria/cytochrome c pathway. Viral HBX protein also interacts with the survivin– HBXIP complex and suppresses caspase activation in a survivin-dependent manner. Thus, HBXIP functions as a cofactor for survivin, and serves as a link between the cellular apoptosis machinery and a viral pathogen involved in hepatocellular carcinogenesis.

We present an overview of the Common Component Architecture (CCA) core specification and CCAFFEINE, a Sandia National Laboratories framework implementation compliant with the draft specification. CCAFFEINE stands for CCA Fast Framework Example In Need of Everything; that is, CCAFFEINE is fast, lightweight, and it aims to provide every framework service by using external, portable components instead of integrating all services into a single, heavy framework core. By fast, we mean that the CCAFFEINE glue does not get between components in a way that slows down their interactions. We present the CCAFFEINE solutions to several fundamental problems in the application of component software approaches to the construction of single program multiple data (SPMD) applications. We demonstrate the integration of components from three organizations, two within Sandia and one at Oak Ridge National Laboratory. We outline some requirements for key enabling facilities needed for a successful component approach to SPMD application building. Copyright © 2002 John Wiley & Sons, Ltd.

This study involves an examination of the changes in the rheological behavior (specifically the non-Newtonian viscosity) of blends of various starches with a synthetic polymer (polyethylene-co-vinyl alcohol) as a result of irradiation-modification. The results are generally consistent with fact that starch degrades substantially upon irradiation, while the synthetic polymer is relatively unaffected. However, the high-amylose starch-containing blends are less sensitive to irradiation than we would expect ; this is attributed to possible interactions between the linear molecules from the high-amylose starch and the synthetic polymer.

Irradiation-modification of the blends of various starches with a synthetic polymer [poly(ethylene-co-vinyl alcohol)] was carried out using an electron beam. The effect of irradiation on neat starches was studies using gel permeation chromatography. Changes in the thermal and mechanical properties of the blends, as well as in their microstructures, were also evaluated. The data indicate, consistent with other reports in literature, that starch molecules fragment under the effect of ionizing radiation, while the EVOH is relatively unaffected. These substantial (mainly physical) modifications to the starch molecules manifest themselves in changes in the thermal behavior of the blends. Furthermore, the mechanical properties of filaments obtained from molten irradiated pellets were quite different from those of control filaments, at least for some starches. Micrographic examination of some blends indicated a correspondence between a modification in the microstructure of the filaments and a change in their mechanical properties. It seems likely that the enhanced mobility of the fragmented starch molecules in the melt is responsible for these changes in the microstructure and concomitantly, the mechanical properties of the blend. Such an irradiation-based physical modification of starch may be of use in tailoring the properties of commercial blends of starches with synthetic thermoplastics. © 1996 John Wiley & Sons, Inc.

Approximate analytical solutions of the local temperature variations, due to viscous heating, in channel flows of non-Newtonian fluids with small Nahme-Griffith numbers were obtained by the WKB-J method. The results are general and easy to use so that extensive numerical computations are not required. Comparisons between the approximate analytical solution and complete numerical solution showed that the relative differences were very small.

Calculations are reported which describe the elongation of flexible macromolecules in a pulse-like elongational How. The polymer molecules are modeled as FENE (finitely extendable nonlinear elastic) dumbbells. The results are in qualitative agreement with experimental results on dilute solutions of polyisobutylene in decalin (10) which form a two parameter family of extension versus position curves. The two parameters-in the FENE model that are used to fit the data are λH, a time constant and b, which is related to the maximum extension that can be achieved by the molecules. Quantitative comparisons are frustrated by difficulty in estimating the model parameter, b. It is suggested, based on this work, that internal self entanglements in the polymers must be considered in the determination of b.

Two batches of a commercially available high-impact polystyrene having different impact strengths were investigated. The steady-shear flow properties, dynamic shear properties, and elongational flow properties of the two were measured. Transmission electron microscopy (TEM) was used to study the microstructure. It is suggested that melt rheology can be a sensitive tool in the characterization of final product properties of rubber-modified polymers: the zero-shear-rate viscosity and the dynamic storage modulus G′, at low frequencies, were experimentally shown to correlate directly with the impact strength, despite the fact that TEM revealed no gross differences in the morphology of the two batches.