In order to simulate the mechanical behavior of large structures assembled from thin composite panels, we propose a coupling technique which substitutes local 3D models for the global plate model in the critical zones where plate modeling is inadequate. The transition from 3D to 2D is based on stress and displacement distributions associated with Saint-Venant problems which are precalculated au...

Earthquakes normally occur as frictional stick-slip instabilities, resulting in catastrophic failure and seismic rupture. Tectonic faults also fail in slow earthquakes with rupture durations of months or more, yet their origin is poorly understood. Here, we present laboratory observations of repetitive, slow stick-slip in serpentinite fault zones and mechanical evidence for their origin. We doc...

A novel technique is reported for screening point mutations is genomic DNA: double gradient, denaturing gradient gel electrophoresis (DG-DGGE). Unlike conventional DGGE, which exploits a single gradient of denaturing chemicals (typically urea and formamide) along the migration path to force the two hetero- and two homo-duplexes to partially unwind and separate, DG-DGGE superimposes a second (po...

The degradation of organic matter in the anoxic seabed proceeds through a complex microbial network in which the terminal steps are dominated by oxidation with sulfate or conversion into methane and CO2 The controls on pathway and rate of the degradation process in different geochemical zones remain elusive. Radiotracer techniques were used to perform measurements of sulfate reduction, methanog...

The introduction of irrigation to agrarian areas involves several environmental changes that can be aggravated by physical and agronomic factors. The aim of this study is to analyze the spatiotemporal dynamics of the environmental impact on water resources that result from the transition of an agrarian basin into an irrigated area. During five hydrological years, a spatiotemporal comparison was...

This study proposes a segmentation procedure based on multivariate texture to extract spatial objects from an image scene. Object uncertainty is quantified to identify transitions zones of objects with indeterminate boundaries. The Local Binary Pattern (LBP) operator, modelling texture, is integrated into a hierarchical splitting segmentation to identify homogeneous texture regions in an image....

In this work we present an efficient strategy to deal with plasma physics simulations in which localized departures from thermodynamical equilibrium are present. The method relies on the introduction of buffer zones which realize a smooth transition between the kinetic and the fluid regions. In this paper we extend the idea, recently developed in [13, 14], of dynamic coupling and of buffer zone...

Transition zones such as level crossing and bridge approaches are critical links in railway networks due to higher degradation rates maintenance needs. In this context, parametric optimization has been applied improve the design transition zones; however, it requires a more computationally efficient tool support repetitive function evaluations, since involved vehicle–track dynamic simulations b...

We investigate dynamical heterogeneities in the collective relaxation of a concentrated microgel system, for which the packing fraction can be conveniently varied by changing the temperature. The packing fraction-dependent mechanical properties are characterized by a fluid-solid transition, where the system properties switch from a viscous to an elastic low-frequency behaviour. Approaching this...