BTA stat and BTA TRAK: A comparative evaluation of urine testing for the diagnosis of transitional cell carcinoma of the bladder

The calcium-activated neutral protease calpain is activated in several pathological conditions. Calpain usually hydrolyses one or only a few peptide bonds in its substrate. One prominent substrate for calpain is spectrin and it has been shown that alpha-spectrin is the preferred substrate. We now show that the beta-chain of spectrin is also a substrate for calpain proteolysis, and that the cleavage site in each beta-subunit is located at the very C-terminal part of the molecule. Surprisingly, beta1sigma-spectrin is cleaved at a different site than betaIsigma2- and betaIIsigma1-spectrins despite their high degree of sequence identity.     

Good reduction of Puiseux series and applications

We have designed a new symbolic-numeric strategy for computing efficiently and accurately floating point Puiseux series defined by a bivariate polynomial over an algebraic number field. In essence, computations modulo a well-chosen prime number p are used to obtain the exact information needed to guide floating point computations. In this paper, we detail the symbolic part of our algorithm. First of all, we study modular reduction of Puiseux series and give a good reduction criterion for ensuring that the information required by the numerical part is preserved. To establish our results, we introduce a simple modification of classical Newton polygons, that we call “generic Newton polygons”, which turns out to be very convenient. Finally, we estimate the size of good primes obtained with deterministic and probabilistic strategies. Some of these results were announced without proof at ISSAC’08.     

Authoring Hierarchical Road Networks

We present a procedural method for generating hierarchical road networks connecting cities, towns and villages over large terrains. Our approach relies on an original geometric graph generation algorithm based on a non‐Euclidean metric combined with a path merging algorithm that creates junctions between the different types of roads. Unlike previous work, our method allows high level user control by manipulating the density and the pattern of the network. The geometry of the highways, primary and secondary roads as well as the interchanges and intersections are automatically created from the graph structure by instantiating generic parameterized models.     

Time-lapse,three-dimensional in situ imaging of ice crystal growth in a colloidal silica suspension

The freezing of colloidal suspensions is encountered in many natural and engineering processes such as the freezing of soils, food engineering and cryobiology. It can also be used as a bio-inspired, versatile and environmentally friendly processing route for porous materials and composites. Yet, it is still a puzzling phenomenon with many unexplained features, owing to the complexity of the system and the space and time scales at which the process should be investigated. This study demonstrates the interest in fast X-ray computed tomography for providing time-lapse, three-dimensional, in situ imaging of ice crystal growth in a colloidal silica suspension. The experimental measurements show that the local increase in colloid concentration does not affect the growth kinetics of the crystals until the colloidal particles become closely packed. For particles much smaller than ice crystals, the concentrated colloidal suspension is equivalent to a simple liquid phase with higher viscosity and a freezing point determined by the concentration of colloidal particles.     

Mechanical properties of nanostructured silicon carbide consolidated by spark plasma sintering

Silicon carbide based materials are foreseen candidates for next generation nuclear applications due to a combination of the following properties: high temperature strength, high thermal conductivity and low nuclear activation. Their main drawback lies in their too low toughness. A promising route to enhance such mechanical properties is to reduce the grain size down to the nanosize range. Enabling a quite low sintering time, the spark plasma sintering technique has been used to process nano size monolithic Silicon carbides with several grain sizes and with or without boron additives. The mechanical properties, including Young modulus, flexural strength and toughness, of these materials have been measured from room temperature to 1300 °C and compared to those of a commercially sintered α-SiC. The results are carefully discussed in correlation with the microstructure. Despite a lower density, the obtained flexural strength and toughness properties of the nano grain silicon carbide are very promising when processed without boron additives. Thus, efforts should be focused on the processing of large size nanograins SiC components by SPS without boron and with high density.