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International audience; Integrated optics has been intensively developed the last decades for the production of components for telecommunications or sensors in metrology. The basic element constitutes the waveguide which transmits the information by guiding the light. The manufacturing processes take place in clean rooms with controlled atmosphere (pressure, temperature, dust) and with generally various deposition and coating machines. The production of these photonics devices remains relatively expensive since it is carried out in a clean room by series of manipulations which requires the intervention of a specialized engineer into a specific environment. More recently, techniques for manufacturing different mechanical parts of mostly research scientific devices have been developed using commercial 3D printers without the need of clean room environment. With such commercial machines, plastic materials are heated and then shaped by controlling their flow through a nozzle. This work concerns the study of the feasibility of realizing and shaping a kind of integrated optics by a simple 3D printer in a normal environment. It aims to understand and develop the fabrication of an integrated planar optics with polymer waveguides using a 3D printer and G-code programming. The coating processes and the G-codes of the 3D printer have been developed in order to produce the thermoplastic polyurethane (TPU) guiding structures onto a silicon/silica wafer. Finally, the characterization of this TPU organic (measurements of surface or energy tension, Raman analysis, ellipsometry measurements) and the optical injection made possible to validate this concept in terms of production and approach. The results concerning the shaping of various rib waveguides and obtaining a propagation of the light in organic thermoplastic polyurethane planar guides with fiber tapers by this simple and low-cost printing processes are positive. This work further proves that the development of integrated optics on thermoplastic polyurethane by 3D printing is possible; this opens the way to the realization of other optical patterns based on the 3D printer principle.

International audience; The understanding and analyzing of solid particle behavior in a liquid is a challenge in numerouse fields and engineering industry as the petroleum or the cosmetic one. It is indeed essential to know the behavior of soft matter process to avoid problems and ensures the product quality. This study presents the viscosimeter development working on a resonant optical signal principle by measuring the Free Spectral Range (FSR) parameter of a resonant optical mode during nanoparticles (NPs) sedimentation in a liquid which consists of a water/glycerol mixture. The photonic structure is composed of racetracks micro-resonators made of a UV210 polymer fabricated by deep-UV photolitography developped on an oxydated silicon layer to get a Si/SiO 2 bi-layer. The chip is then integrated in an optical bench to track the evolution of the FSR during the complet sedimentation process. The resonant signal analyse established by an adapted signal processing of silica nanoparticles sedimentation in different water/glycerol concentrations allows us to determine stages and velocity rate of the sedimentation process to finaly access to their viscosity. At the same time, measures are performed on a commercial mechanical rheometer so as to compare the dynamic evolution of their viscosity and their associated FSR. The plot of those data versus the glycerol concentration in water obviously shows a possible mathematical transformation between viscosity and FSR slope. There is therefore a good agreement between mechanical and resonant optical measures if we consider the dynamic evolution of both curves ; so this work proves the feasability of an optical viscosimeter based on resonant signal.

National audience; The understanding and analyzing of solid particle behavior in a liquid is a challenge in numerouse fields and engineering industry as the petroleum or the cosmetic one. It is indeed essential to know the behavior of soft matter process to avoid problems and ensures the product quality. This study presents the viscosimeter development working on a resonant optical signal principle by measuring the Free Spectral Range (FSR) parameter of a resonant optical mode during nanoparticles (NPs) sedimentation in a liquid which consists of a water/glycerol mixture. The photonic structure is composed of racetracks micro-resonators made of a UV210 polymer fabricated by deep-UV photolitography developped on an oxydated silicon layer to get a Si/SiO2 bi-layer. The chip is then integrated in an optical bench to track the evolution of the FSR during the complet sedimentation process. The resonant signal analyse established by an adapted signal processing of silica nanoparticles sedimentation in different water/glycerol concentrations allows us to determine stages and velocity rate of the sedimentation process to finaly access to their viscosity. At the same time, measures are performed on a commercial mechanical rheometer so as to compare the dynamic evolution of their viscosity and their associated FSR. The plot of those data versus the glycerol concentration in water obviously shows a possible mathematical transformation between viscosity and FSR slope. There is therefore a good agreement between mechanical and resonant optical measures ; so this work proves the feasability of an optical viscosimeter based on resonant signal.

National audience; Cette étude expose le développement d’un viscosimètre optique qui mesure l’Intervalle Spectral Libre (ISL) d’un mode optique résonant lors de la sédimentation de nanoparticules dans un mélange eau/glycérol. L’utilisation du signal résonant afin d’analyser la sédimentation de nanoparticules dans l’eau a déjà fait l’objet d’une étude antérieure[1]. La structure photonique est composée de micro-résonateurs en forme de « circuit de course » constitués du polymère UV210 développé par photolithographie dans l’UV profond sur une bi-couche Si/SiO2. Le tracé de la viscosité (mesurée par un rhéomètre mécanique commercial) par rapport à la pente de l’ISL durant le processus de sédimentation en fonction de la concentration en glycérol montre une transformation mathématique possible entre ces données. Le bon accord entre les mesures mécaniques et optiques prouve la faisabilité d'un viscosimètre optique basé sur un signal résonant. Afin d’étendre l’étude à des liquides pouvant attaquer les guides d’ondes organiques, des procédés matériaux ont été réalisés pour les protéger[2]. Deux dépôts par PECVD à basse température permettent de réaliser des structures Si/SiO2/UV210/Si/SiO2. Une mesure statistique de l’ISL assure la qualité de ces nouvelles puces photoniques.

National audience; The ability of optical integrated polymeric resonator to act as sensors has been proven several times[1]. Furthermore, in recent years nanophotonics has strongly developed bases on specific symmetric silicon on- insulator (SOI) or SiO2/Si /SiO2 structures[2]. Processes for the realization of complex structures of semiconductors on insulators based on an organicUV210 are detailed here[3]. The advantage of processingthe Si /SiO2/UV 210/Si /SiO2 symmetry is linked to electromagnetism’s equations that no longer impose a cut-off thickness. This innovative integrated photonic also allows the study of aggressive substance without damaging the organic thanks to an upper layer covering the component. Several families of multilayers and structures are processed by PECVD interactions and are properly characterized by ellipsometric and Raman analyses. Resonant structures are also cleanly characterized by Free Spectral Rangemeasurements (Fig. 1).

In the stamping of industrial parts, friction and lubrication play a key role in achieving high quality products and reducing scrap. Especially in the start-up phase of new production runs, transient effects can have a significant impact on the product quality. Before a steady-state production run is established, heating up of tools influence tribological conditions. This influences the performance of the forming operation and, consequently, the quality of the formed product. In the development process of new industrial parts, it is therefore crucial to accurately account for these transient effects in sheet metal forming simulations. This paper presents the modeling of the frictional behavior of two tribological systems as developed within the ASPECT project. The first tribology systems consist of a stainless steel with corresponding drawing oil and tool material. The sheet material of the second tribology system is a hot dip galvanized bake hardened steel. Subsequently, it is shown how temperature affects the frictional behavior of these tribology systems. Finally, generated friction models have been applied to a spare wheel well of Opel. The spare wheel well is modelled using a generally applicable approach to account for transient effects under industrial sheet metal forming process conditions. For varying temperature and tribological conditions, the spare wheel well can show cracks and differences in thinning and draw-in. This emphasizes the strong influence of transient effects on both part quality and the overall production stability.

National audience; Resonant light signals have already proven their ability to follow phase transitions of products in biology [1], agri-food and cosmetics [2]. These phase transitions may or may not present an enthalpy variation, being only a conformation/structural change [2] of the product. We will present that the processing of such resonant light signals could recently allow the detection of interface approach between fluids [3], the sedimentation rate of nanoparticles in colloids [4]; this kind of application is useful in many areas as galenic pharmacology with colloids, energy and electronics with oils, agri-food with cream and foam. We will conclude with the application of such resonant surface light technology to possible differential measurements of blood viscosities (poultry, goat, human) [5].

International audience; Today, the genus Scedosporium comprises at least ten species with four of them, Scedosporium apiospermum, Scedosporium boydii, Scedosporium aurantiacum and Scedosporium minutisporum capable of colonizing the lungs of patients with cystic fibrosis. Scedosporium dehoogii, which is also common in the soil, has never been reported as causing human pulmonary infections. Here we report the first genome sequence for S. dehoogii, an invaluable resource to understand the genetic bases of pathogenesis in the genus Scedosporium.

Moumeni L, Gastebois A, Gillmann L, Papon N, Benia F, Bouchara J-P, Bounechada M. 2021. Investigating the prevalence of Bark beetles of Pinus halepensis in the North East semi-arid region of Algeria. Biodiversitas 22: 2755-2762. Aleppo pine is the most common tree in the semi-arid forests of Algeria. Despite its high resistance to drought and adaptability to all types of soils, the effects of climate change are affecting it directly and indirectly. Stressed trees indeed are subject to bark beetle attacks. In this study, we sampled the bark beetles directly from the affected pine trees. Six species belonging to the Scolytinae subfamily were identified. Tomicus detruens and Orthotomicus erosus were widely spread and present in the three studied forests, where they were found to colonize living trees while Crypturgus numidicus, Crypturgus mediterraneus, Hylurgus ligniperda and Hylurgus micklitzi colonized only dead trees. Together with future identification of the microfungi associated with these xylophagous insects, these data may help to define prevention measures to fight the decline of Aleppo pine forests observed in some parts of Eastern Algeria.

Today, the genus Scedosporium comprises at least ten species with four of them, Scedosporium apiospermum, Scedosporium boydii, Scedosporium aurantiacum and Scedosporium minutisporum capable of colonizing the lungs of patients with cystic fibrosis. Scedosporium dehoogii, which is also common in the soil, has never been reported as causing human pulmonary infections. Here we report the first genome sequence for S. dehoogii, an invaluable resource to understand the genetic bases of pathogenesis in the genus Scedosporium.

The numerical simulation of multi-strokes sheet metal cold forming is very CPU time consuming especially if all relevant physical phenomena are considered. For a single stroke FE simulation, although the process is cold forming, thermo-mechanical coupling should be taken into account. Moreover, friction between the blank and the tools should be correctly modeled. If such complexity is included for the simulation of a single stroke in cold forming, simulating multi-strokes process and maybe multi-steps cold metallic sheet forming, will be extremely CPU time consuming and even unrealistic to be performed. In this work, the authors propose a speed-up method called “jump in strokes method”, which allows a CPU reduction up to 60%. This method was applied for two industrial use cases: the first one was proposed by Philips representing small parts used in shavers and the second one by Opel representing the production of large panels in automotive industry.