Microstructure Effects in Multidipped Tin Oxide Films

Porous ultrafine tin oxide films (particle size 70–90 Å) have been prepared from tin alkoxide by dip coating. The influence of the number of coating applications on the thickness, microstructure, and electrical properties of multidipped tin oxide films was investigated. With an increase in the number of coating applications, the porosity of the multidipped films decreased from 60% to 12%, but the particle size of the films increased. The resistivity of the films decreased from 5.5 × 10^–2 to 5.7 × 10^–3Ω·cm with increasing the number of coating applications from 1 to 10. This tendency of the resistivity to decrease is due to the microstructural change of the films with the number of coating applications. The microstructure, the surface structure, and the composition of the multidipped films were investigated by scanning electron microscopy (SEM), X-ray diffraction (XRD), and Auger electron spectroscopy (AES).     

Cognitive networks: adaptation and learning to achieve end-to-end performance objectives

In this article we advance the idea of a cognitive network, capable of perceiving current network conditions and then planning, learning, and acting according to end-to-end goals. Cognitive networks are motivated by the complexity, heterogeneity, and reliability requirements of tomorrow's networks, which are increasingly expected to self-organize to meet user and application objectives. We compare and contrast cognitive networks with related research on cognitive radios and cross-layer design. By defining cognitive networks, examining their relationship to other technologies, discussing critical design issues, and providing a framework for implementation, we aim to establish a foundation for further research and discussion     

Sonography and quantitative measurements

A preliminary study of coronary artery wall topography and mechanical properties is presented. The aim of this study was to give a brief demonstration of scanning acoustic microscopy (SAM) as a sonographic technique, and to apply the time-resolved SAM (TR-SAM) technique for quantification of coronary artery wall mechanical properties under passive conditions ex-vivo, and compare the data for the tunica externa and tunica media of the wall. The authors chose the diagonal branches of the left anterior descending coronary artery (LADCA) of young healthy pigs for measurements. It is concluded that SAM is well suited for sonography at the micrometer level, and TR-SAM provides a refined tool for biorheological quantification ex-vivo, provided that a number of physical factors influencing measurements and tissue properties are considered and dealt with. With time and effort, SAM may also become a valuable tool for recognizing important relations of composition and structure to function. For future SAM studies of arteries, more detailed analyses of layer interfaces and better models of biorheology should be applied to describe the anisotropy and nonlinear viscoelasticity of the wall     

Detection of antineutrophil cytoplasmic antibodies in primary sclerosing cholangitis: a comparison of the alkaline phosphatase and immunofluorescent techniques

SSCP (single-strand conformational polymorphism) is used widely in the field of human biomedicine, but its potential as a population genetics tool for the recovery of nuclear gene genealogies remains to be realized. We describe and illustrate a use for SSCP in the physical isolation of nuclear haplotypes that circumvents several difficulties associated with more conventional cloning procedures. The DNA sequence can be determined directly from the isolated haplotypes and used for phylogenetic inference. SSCP provides a convenient first step toward generating nuclear genealogies for population studies.     

Practical guidelines for expert-judgment-based software effort estimation

This article presents seven guidelines for producing realistic software development effort estimates. The guidelines derive from industrial experience and empirical studies. While many other guidelines exist for software effort estimation, these guidelines differ from them in three ways: 1) They base estimates on expert judgments rather than models. 2) They are easy to implement. 3) They use the most recent findings regarding judgment-based effort estimation. Estimating effort on the basis of expert judgment is the most common approach today, and the decision to use such processes instead of formal estimation models shouldn't be surprising. Simple process changes such as reframing questions can lead to more realistic estimates of software development efforts.     

Laboratory issues in the detection and reporting of antibacterial resistance

The emergence of antimicrobial resistance among several common bacterial pathogens requires that clinical microbiology laboratories have the ability to promptly and accurately recognize resistance in patients' isolates. Laboratories have several options for performing routine susceptibility testing, including the broth microdilution procedure (with or without instrumentation for test reading), automated instrument systems that provide rapid results, antibiotic gradient diffusion, and disk diffusion procedures. In addition, there are definitive screening tests capable of recognizing resistance to drugs of choice among several common bacterial species based on single drug concentration tests or rapid spot tests. The likely emergence of still newer resistance mechanisms will provide a challenge to clinical microbiologists to devise accurate, yet cost-effective strategies for use in the future.     

Reprocessing of thermally oxidized aluminum arsenide (AlAs) in epitaxial multilayers without delamination

Annealing or processing of AlAs that has been subjected to a wet thermal oxidation process can result in severe delamination of material at the oxidation front. This paper reports a procedure for preventing this delamination and presents a possible cause for the delamination.