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Migration and sedimentation of solid particles in a liquid are physical phenomena involving accumulation of soft matter or decantation of fragmented matter. A thorough understanding together with relevant measurements are prerequisites regarding many fields, including medicine, galenic pharmacology, food processing, and the cosmetics industry. In this paper, we investigate the feasibility of monitoring and detecting the migration of a nanoparticle cloud with a resonant light probe. For this purpose, hybrid silicon/silica/UV210 organic integrated photonic racetrack resonators were patterned by thin film processes to be used as sensors measuring the outcome of the impact of a cloud of nanoparticles, the dynamic migration plus sedimentation phenomenon of the nanoparticle cloud in water. A broadband superluminescent diode has been used for the excitation. Then, the spectral characteristics of the resonant guided modes have been analyzed, considering the observed changes while tracking the free spectral range of the transduced comb spectra as a function of time. The way to operate can be summarized as follows: Solutions based on spherical silica nanoparticles of fixed size are prepared and subjected to rheological measurements to obtain their respective viscosities. Next, a millimeter tank filled with water is conveniently placed on the active surface of the sensing chip, prior to the addition of one of the previously mentioned solutions. The series of spectra are acquired during the whole migration sequence and the transduced optical signal is then directly processed and treated by a specific code operated in real time by way of Lagrange interpolation polynomials. Collected data are then compared to a simple theoretical model describing the sedimentation of a spherical particle in water (Stokes' law). Eventually, the implementation of the device in a characterization platform and the development of a specific protocol allows a global treatment, whose description is followed by discussions on measurements and data. Consequently, after the impact of the drop containing the nanoparticles, the monitoring of a first phase regarding their fast cloud migration into the global study volume (with flow of matter plus vortex) eventually followed by their slow sedimentation, can be detected using such a resonant light probe. The overall duration of the first phase associated with sedimentation velocities is in the order of a few tens of µm/min for particles with submicron diameters (several hundreds of nanometers); a first attempt of comparison of this first phase with the results of the classic Stokes model would give a convergence of the values reaching between 9 and 19% for the sedimentation rates.

The numerical simulation of Friction Stir Welding (FSW) is carried out using an Arbitrary Lagrangian or Eulerian (ALE) formulation. Its computational cost is reduced by appealing to the parallel version recently developed within the Forge software. The accuracy of the numerical model is increased by enhancing the state variables remapping algorithm and by introducing a better suited time integration scheme based on the cylindrical coordinates. The pin and shoulder threads are modelled in order to account for this crucial phenomenon on material heating. The developed model provides quite satisfactory temperature fields for the FSW of a butt joint of 6061 aluminium, as compared to experimental results. It allows simulating welding defects such as tunnels holes or flashes. The study then focuses on numerical simulations and experimental measurements of a lap joint of a 7175 aluminium sheet on a 2024 aluminium sheet for an aeronautical application.

The β(1-3)glucanosyltransferase GEL family of Aspergillus fumigatus contains 7 genes, among which only 3 are expressed during mycelial growth. The role of the GEL4 gene was investigated in this study. Like the other Gelps, it encodes a glycosylphosphatidylinositol (GPI)-anchored protein. In contrast to the other β(1-3)glucanosyltransferases analyzed to date, it is essential for this fungal species.

One-proton and one-neutron stripping reactions induced by a 793 MeV16O beam bombarding a208Pb target have been studied at the GANIL facility using a high resolution energy loss magnetic spectrometer. The reactions are governed by two semi classical selection rules which are naturally contained in the one-step EFR-DWBA formalism. Relative intensities of the populated states are well reproduced by this formalism which, on the other hand, fails to predict correctly absolute cross section values.

ABSTRACTHistidine kinases (HKs) are among the most prominent sensing proteins studied in the kingdom Fungi. Their distribution and biological functions in early diverging fungi (EDF), however, remain elusive. We have taken advantage of recent genomic resources to elucidate whether relationships between the occurrence of specific HKs in some EDF and their respective habitat/lifestyle could be established. This led to the unexpected discovery of fungal HKs that share a high degree of similarity with receptors for plant hormones (ethylene and cytokinin). Importantly, these phytohormone receptor homologs are found not only in EDF that behave as plant root symbionts or endophytes but also in EDF species that colonize decaying plant material. We hypothesize that these particular sensing proteins promoted the interaction of EDF with plants, leading to the conquest of land by these ancestral fungi.