In vivo evaluation of chemical biopersistence of nonfibrous inorganic particles.

The lung's response to deposited particles may depend upon the physical-chemical properties of the particles, the amount initially deposited, and the persistence of the particles. Clearance involves mucociliary transport as well as the action of phagocytic cells in nonciliated regions of the lung. Depending on the animal species studied, particle type, and particle load, inorganic materials are ingested by macrophages on alveolar surfaces with half-times of 0.6 to 7 hr. Particle-laden macrophages may migrate to airways, but we believe that an important mechanism of clearance is the dissolution of particles within alveolar macrophages and the subsequent translocation of dissolved materials to the blood. Particle dissolution in situ has long been recognized but was often thought to be carried out extracellularly in the alveolar lining layer, airway mucus, or interstitial fluid. However, many particles such as cobalt oxide or iron oxide which dissolve very little in simulated lung fluid, are solubilized more rapidly within alveolar macrophages. Clearance of particles from the lungs can be followed by a number of techniques, both invasive and noninvasive. The approaches vary in expense and resolution, and can be directed toward quantifying mechanical removal of particles versus their intracellular dissolution. Noninvasive methods permit repeated measurements of particle retention in the lungs of the same animal or human and thus allow replications and serial measurements. Greater precision with respect to the sites of retention and redistribution is achieved with quantitative morphometric methods that utilize fixation followed by physically dividing the respiratory tract into individual pieces.(ABSTRACT TRUNCATED AT 250 WORDS

Learning from the past with experiment databases

Thousands of Machine Learning research papers contain experimental comparisons that usually have been conducted with a single focus of interest, and detailed results are usually lost after publication. Once past experiments are collected in experiment databases they allow for additional and possibly much broader investigation. In this paper, we show how to use such a repository to answer various interesting research questions about learning algorithms and to verify a number of recent studies. Alongside performing elaborate comparisons and rankings of algorithms, we also investigate the effects of algorithm parameters and data properties, and study the learning curves and bias-variance profiles of algorithms to gain deeper insights into their behavior

The ADHM Construction of Instantons on Noncommutative Spaces

We present an account of the ADHM construction of instantons on Euclidean space-time $\mathbb{R}^4$ from the point of view of noncommutative geometry. We recall the main ingredients of the classical construction in a coordinate algebra format, which we then deform using a cocycle twisting procedure to obtain a method for constructing families of instantons on noncommutative space-time, parameterised by solutions to an appropriate set of ADHM equations. We illustrate the noncommutative construction in two special cases: the Moyal-Groenewold plane $\mathbb{R}^4_\hbar$ and the Connes-Landi plane $\mathbb{R}^4_\theta$.Comment: Latex, 40 page

The JKind Model Checker

JKind is an open-source industrial model checker developed by Rockwell Collins and the University of Minnesota. JKind uses multiple parallel engines to prove or falsify safety properties of infinite state models. It is portable, easy to install, performance competitive with other state-of-the-art model checkers, and has features designed to improve the results presented to users: inductive validity cores for proofs and counterexample smoothing for test-case generation. It serves as the back-end for various industrial applications.Comment: CAV 201