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In this paper, we presented the design and simulation results of a platinum meander–spiral combination micro heater for a zinc oxide (ZnO) gas sensor. As a first step, different optimizations have been performed using a finite element analysis in order to obtain a compromise between maximum temperature, maximum homogeneity in active area and minimum power consumption. In the other hand, the effect of ZnO sensitive layer was studied.

We investigate the nucleation, domain formation and propagation mechanisms observed in Spin Crossover materials, in the framework of an Ising-like model taking into account the elastic nature of the interactions. In Spin Crossover materials, the intermolecular coupling originates from a volume difference between the High Spin and the Low Spin molecular states and is simulated by anharmonic interaction potentials whose strengths are molecular-state-dependent. Using Monte Carlo methods, the phase diagram has been established. We show that the model contains both Ising short-range couplings and long-range elastic interactions. In particular, the results of long-range elastic models are reproduced. The introduction of lattice dynamics leads to the existence of spatial distributions of interaction energy and crystal field, corresponding to a local definition of physical properties. The nucleation process becomes highly dependent on the structural inhomogeneities induced by the spin transition. In this approach, connections strength between neighboring molecules are no more equivalent and have different ability to propagate domains. The presence of short-range Ising couplings gives rise to the occurrence of strong bonds forming a volume in which domains of the daughter phase can grow; in this case a macroscopic phase separation appears during the first order transition, even in a system with periodic boundary conditions. By contrast, in the case of a model with only long-range elastic interactions; strong bonds are uniformly spread in the lattice and a homogeneous phase transformation is observed, in good agreement with previous theoretical investigations.

We investigate the nucleation, domain formation and propagation mechanisms observed in Spin Crossover materials, in the framework of an Ising-like model taking into account the elastic nature of the interactions. In Spin Crossover materials, the intermolecular coupling originates from a volume difference between the High Spin and the Low Spin molecular states and is simulated by anharmonic interaction potentials whose strengths are molecular-state-dependent. Using Monte Carlo methods, the phase diagram has been established. We show that the model contains both Ising short-range couplings and long-range elastic interactions. In particular, the results of long-range elastic models are reproduced. The introduction of lattice dynamics leads to the existence of spatial distributions of interaction energy and crystal field, corresponding to a local definition of physical properties. The nucleation process becomes highly dependent on the structural inhomogeneities induced by the spin transition. In this approach, connections strength between neighboring molecules are no more equivalent and have different ability to propagate domains. The presence of short-range Ising couplings gives rise to the occurrence of strong bonds forming a volume in which domains of the daughter phase can grow; in this case a macroscopic phase separation appears during the first order transition, even in a system with periodic boundary conditions. By contrast, in the case of a model with only long-range elastic interactions; strong bonds are uniformly spread in the lattice and a homogeneous phase transformation is observed, in good agreement with previous theoretical investigations.

Catastrophic deep-seated landslides (DSL) are generally considered to be the result of large slope deformations also known as deep-seated gravitational slope deformation (DSGSD). This paper aims to build a synthesis of multiple studies made in the Tinée Valley (southern French Alps) to assess the geometrical, kinematical, mechanical and chronological relationships between these two gravitational processes. At the scale of the valley, data issued from geological, geomorphological and 10Be dating indicate a clear geometrical link between DSGSD and DSL occurring at the base of the slope and suggest that gravitational slope evolution began after the glacial retreat (13 ka BP). This is supported by the example of the well-documented La Clapière slope. A continuous evolution process is characterized geometrically and temporally from geomorphic observations and analogue modelling. Coupling structural, geomorphological, physical and chronological studies allowed us to propose a four-dimensional (4D) deformation model mechanically correlated with progressive failure concept. The validity and variability of this reference site are discussed at the valley scale (taking Isola and Le Pra slope deformation as examples). It allows a rough estimation of the state of slope deformation at the valley scale to be constructed and the slope evolution with time to be considered. This 4D model could then be considered as a reference for other deep-seated gravitational slope deformations in comparable Alpine valleys.

La chirurgie robotisée est en plein essor dans de nombreuses spécialités chirurgicales. En chirurgie oncologique tête et cou, cette nouvelle procédure pourrait être une bonne alternative chirurgicale, en espérant diminuer la morbidité liée à certaines techniques plus conventionnelles. L’objectif de cet article est d’établir un état des connaissances acquises dans ce domaine avec une revue de la littérature. Nous soulignons les limites et perspectives avec un regard particulier sur les aspects de sûreté de fonctionnement. Le robot chirurgical appliqué en chirurgie endoscopique ORL est un outil prometteur sous réserve, cependant, du développement attendu de nouvelles fonctions comme un système de navigation ou un retour de force couplés au robot. Le bon développement de ce nouvel outil dépendra également de la qualité des travaux et programmes de recherche dans ce domaine.

Les teignes du cuir chevelu touchent essentiellement l’enfant à l’âge scolaire et préscolaire. Elles constituent un problème préoccupant pour la santé publique. Le but de ce travail est de préciser le profil clinico-épidémiologique des agents pathogènes des teignes dans la région de Gafsa.