Relationships between sensorial characteristics and microbial dynamics in "Registered Designation of Origin" Salers cheese

Raw milk cheeses show a wide diversity of sensorial characteristics, largely determined by the microflora of raw milk. Microbial dynamics in Registered Designation of Origin (R.D.O.) Salers cheese was assessed by DNA and RNA SSCP analysis on nine cheeses. These cheeses showed considerable diversity both in microbial dynamics and sensorial characteristics. Relationships between the sensorial characteristics and the microbial dynamics were studied. A global consideration of bacterial dynamics demonstrated that other bacteria than lactic acid bacteria can play a role in the elaboration of sensorial characteristics. Indeed, high CG% Gram-positive bacteria can be involved. DNA data, as well as RNA data, appeared relevant to attempts to explain sensorial variance. Correlations between sensorial and microbial data were rather complex. Several microbial variables for DNA and RNA analyses, noted at different times of analysis, were correlated to each sensory variable. A global view of cheese microbial community proved to be insufficient in explaining the diversity of the sensorial qualities of R.D.O. Salers cheese.     

Compact preference representation and Boolean games

Game theory is a widely used formal model for studying strategical interactions between agents. Boolean games (Harrenstein, Logic in conflict, PhD thesis, 2004; Harrenstein et al., Theoretical Aspects of Rationality and Knowledge, pp. 287–298, San Francisco Morgan Kaufmann, 2001) yield a compact representation of 2-player zero-sum static games with binary preferences: an agent’s strategy consists of a truth assignment of the propositional variables she controls, and a player’s preferences are expressed by a plain propositional formula. These restrictions (2-player, zero-sum, binary preferences) strongly limit the expressivity of the framework. We first generalize the framework to n-player games which are not necessarily zero-sum. We give simple characterizations of Nash equilibria and dominated strategies, and investigate the computational complexity of the associated problems. Then, we relax the last restriction by coupling Boolean games with a representation, namely, CP-nets. This article is a revised and extended version of the two conference articles [4] and [3].     

Complexity results for the horizontal bar packing problem

This paper deals with the packing of a grid by horizontal bars while respecting given orthogonal projections and several constraints of distance between the consecutive bars. We show that packing under a maximal or uniform distance is an NP-complete problem. We also give a polynomial time algorithm to solve the packing problem under a minimal distance.     

Local/global non-intrusive crack propagation simulation using a multigrid X-FEM solver

A Local/global non-intrusive coupling algorithm is proposed for the analysis of mixed-mode crack propagation. It is based on a three scale multigrid and extended finite element method, that was proposed recently for the direct estimation of stress intensity factors of static cracks. The algorithm couples a linear elastic global model (possibly performed by a industrial software) with an enhanced local model capable of modeling a crack and accurately estimating SIFs (performed by a separate research code). It is said non-intrusive since it does not modify the global mesh, its connectivity and solver. For the global model, the contribution of the local patch consists in additional nodal efforts near the crack, which makes it compatible with most softwares. Further the shape of the domain over which the local model is applied is automatically adapted during propagation.     

Optimised NSAIDs-loaded Biocompatible Nanoparticles

Nano-Micro Letters - In this formulation study, biocompatible non steroidal anti-inflammatory (NSAIDs)-loaded nanoparticles were designed as models to be further integrated in a prosthesis surface...     

A general dynamic model for multiphase electrolytic systems

The study and characterization of aqueous solutions are becoming an important research topic because of their central role in many processes. The modeling of these solutions is complicated by different factors: the important number of ionic and nonionic species, the nonideality of aqueous solutions, the appearance and disappearance of thermodynamic phases (solid, vapor) depending on operating conditions. This article presents a general model in dynamic state of aqueous electrolytic system involving liquid, vapor, and solid phases. The mathematical formulation includes: physical and chemical equilibria, mass and energy balances, electroneutrality equation and evaporation equation. The set of equations is solved by the Gear's method. The model is validated by the comparison between modeled results (activity coefficients, solubility, evaporite sequence) and experimental data. One of the purposes of the model will be the simulation of a production process of salt crystals and waters concentrated in minerals of interest. © 2012 American Institute of Chemical Engineers AIChE J, 2012     

Formalisation of a new prognosis model for supporting proactive maintenance implementation on industrial system

The importance of the maintenance function has increased because of its role in keeping and improving system availability and safety, as well as product quality. To support this role, the maintenance concept has undergone several major developments that have led to proactive considerations mainly based on a prognosis process, which normally allows selection of the best maintenance action to be carried out. This paper proposes the deployment and experimentation of a prognosis process within an e-maintenance architecture. The deployment follows a methodology based on the combination of both a probabilistic approach for modelling the degradation mechanism and of an event one for dynamical degradation monitoring. The feasibility and benefits of this new prognosis process is investigated with an experiment using a manufacturing TELMA (TELe-MAintenance) platform supporting the unwinding of metal bobbins.     

As oxidation by Thiomonas arsenivorans in up-flow fixed-bed reactors coupled to As sequestration onto zero-valent iron-coated sand

The combined processes of biological As^III oxidation and removal of As^III and As^V by zero-valent iron were investigated with synthetic water containing high As^III concentration (10 mg L⁻¹). Two up-flow fixed-bed reactors (R1 and R2) were filled with 2 L of sieved sand (d = 3 ± 1 mm) while zero-valent iron powder (d = 76 μm; 1% (w/w) of sand) was mixed evenly with sand in R2. Thiomonas arsenivorans was inoculated in the two reactors. The pilot unit was studied for 33 days, with HRT of 4 and 1 h. The maximal As^III oxidation rate was 8.36 mg h⁻¹ L⁻¹ in R1 and about 45% of total As was removed in R2 for an HRT of 1 h. A first order model fitted well with the As^III concentration evolution at the different levels in R1. At the end of the pilot monitoring, batch tests were conducted with support collected at different levels in R1. They showed that bacterial As^III oxidation rate was correlated with the axial length of reactor, which could be explained by biomass distribution in reactor or by bacterial activity. In opposition, As^III oxidation rate was not stable in R2 due to the simultaneous bacterial As^III oxidation and chemical removal by zero-valent iron and its oxidant products. However, a durable removal of total As was realized and zero-valent iron was not saturated by As over 33 days in R2. Furthermore, the influence of zero-valent iron and its oxidant corrosion products on the evolution of As^III-oxidizing bacteria diversity was highlighted by the molecular fingerprinting method of PCR-DGGE using aoxB gene as a functional marker of aerobic As^III oxidizers.     

Three dimensional experimental and numerical multiscale analysis of a fatigue crack

A full three dimensional study of a fatigue crack in cast iron is presented. This analysis involves combining various tools, namely, Synchrotron X-ray microtomography of an in situ experiment, image acquisition and treatment, 3D volume correlation to measure 3D displacement fields, extraction of the crack geometry, eXtended Digital Volume Correlation to account for the crack displacement discontinuity, crack modeling in an elastic material exploiting the actual crack geometry, and finally estimation of stress intensity factors. All these different tasks are based on specific multiscale approaches.