The sol–gel route: A versatile process for up-scaling the fabrication of gas-tight thin electrolyte layers

Sol–gel routes are often investigated and adapted to prepare, by suitable chemical modifications, submicronic powders and derived materials with controlled morphology, which cannot be obtained by conventional solid state chemistry paths. Wet chemistry methods provide attractive alternative routes because mixing of species occurs at the atomic scale. In this paper, ultrafine powders were prepared by a novel synthesis method based on the sol–gel process and were dispersed into suspensions before processing. This paper presents new developments for the preparation of functional materials like yttria-stabilized-zirconia (YSZ, 8% Y2O3) used as electrolyte for solid oxide fuel cells. YSZ thick films were coated onto porous Ni-YSZ substrates using a suspension with an optimized formulation deposited by either a dip-coating or a spin-coating process. The suspension composition is based on YSZ particles encapsulated by a zirconium alkoxide which was added with an alkoxide derived colloidal sol. The in situ growth of these colloids increases significantly the layer density after an appropriated heat treatment. The derived films were continuous, homogeneous and around 20 μm thick. The possible up-scaling of this process has been also considered and the suitable processing parameters were defined in order to obtain, at an industrial scale, homogeneous, crack-free, thick and adherent films after heat treatment at 1400 °C

Structural study of metastable tetragonal YSZ powders produced via a sol-gel route

Sol-gel yttria stabilized zirconia (YSZ) is investigated in this paper. The final aim is to process YSZ powders into stable slurries in order to prepare thick coatings for thermal barrier to be applied on hot turboengine components. In fact, this system is well-known for its excellent thermomechanical resistance at elevated temperatures but the relationship between these performances and the structural and microstructural characteristics of these materials is not fully understood. This paper reports a preliminary study concerning recent progress on the structural properties control of YSZ powders synthesized by solâ��gel process and the main advantages of this process compared to conventional methods. As a first step towards this understanding, structural investigations of ZrO2 doped with various xmol%YO1.5 coatings, have been performed using X-ray diffraction, structural Rietveld refinement, Raman spectra analysis and transmission electron microscopy. The evolution of the crystallographic structure of YSZ powders after air annealing at various temperatures 1100 °C, 1200 °C and 1400 °C was studied to well understand the conditions of the formation of desired metastable tetragonal phase (t). Then, this work should allow to correlate chemical and thermomechanical parameters as YSZ formulation and sol-gel elaboration conditions, temperature and t phase performances

Transverse Reflexive Simulation: a method for anchoring human activity at the heart of the company’s performance

Cet article présente la genèse et la mise en œuvre d’une méthode qui a consisté à simuler l’activité de traitement d’une demande client dans le domaine de la relation de service. L’objectif de cette simulation était double: révéler une activité collective qui se déroule de façon distribuée dans le temps et dans l’espace et identifier des leviers de transformation pour faciliter et fluidifier la relation de service. Cette simulation, que nous avons nommée « Simulation Réflexive Transverse » convoque le travail par le biais des connaissances acquises sur l’activité humaine dans ses différentes dimensions au travers d’un programme de recherche technologique existant au sein de la R&D (Recherche et Développement) d’une grande entreprise. Elle permet ainsi de travailler sur la continuité, élément crucial de la qualité de service et de la satisfaction client, en ouvrant des espaces de construction de cette continuité. En favorisant le développement des individus, des collectifs et des organisations, la Simulation Réflexive Transverse contribue à la performance de l’entreprise sur le long terme.This article presents the genesis and implementation of a method that consisted in simulating the activity of processing a customer request in the field of the service relationship. The purpose of this simulation was twofold: to reveal a collective activity that unfolds in a distributed way in time and space and to identify the levers of transformation to facilitate the service relationship and make it more fluid. This simulation, known as "Transverse Reflexive Simulation", elicits the work thanks to the knowledge acquired on human activity in its various dimensions in an existing research programme in the R&D (Research and Development) division of a large company. It makes it possible to work on continuity, an element crucial to quality of service and customer satisfaction, by opening spaces for constructing this continuity. By promoting the development of individuals, collectives and organizations, Transverse Reflexive Simulation contributes to the company's long-term performance

Antitumor Effects of Clinical Dosing Regimens of Bisphosphonates in Experimental Breast Cancer Bone Metastasis

Background Bisphosphonates exhibit direct antitumor activity in animal models, but only at high doses that are incompatible with the clinical dosing regimens approved for the treatment of cancer patients with skeletal metastases. We compared the antitumor effects of clinical dosing regimens of the bisphosphonates zoledronic acid and clodronate in a mouse model of bone metastasis. Methods Mice (n = 6-10 per group) were treated with zoledronic acid, clodronate, or vehicle starting before (preventive protocols) or after (treatment protocols) intravenous injection with human B02/GFP.2 breast cancer cells, which express green fluorescent protein (GFP) and luciferase and metastasize to bone. Zoledronic acid was given as daily, weekly, or single doses at a cumulative dose of 98-100 μg/kg body weight, equivalent to the 4-mg intravenous dose given to patients. Clodronate was given as a daily dose (530 μg/kg/day), equivalent to the daily 1600-mg oral clinical dose given to patients. Bone destruction was measured by radiography, x-ray absorptiometry or tomography, and histomorphometry (as the ratio of bone volume to tissue volume). Skeletal tumor burden was measured by histomorphometry (as the ratio of tumor burden to soft tissue volume [TB/STV]) and luciferase activity. All statistical tests were two-sided. Results In treatment protocols, daily clodronate was less effective at decreasing the TB/STV ratio than daily (53% versus 87%, difference = 34%, 95% confidence interval [CI] = 16% to 44%, P<.001) or weekly (53% versus 90%, difference = 37%, 95% CI = 19% to 46%, P<.001) zoledronic acid-dosing regimens. Compared with vehicle, a single dose of zoledronic acid decreased tumor burden by only 16% (95% CI = 9% to 22%, P<.001). In preventive protocols, daily clodronate and daily or weekly zoledronic acid decreased the TB/STV ratio by 49% (95% CI = 40% to 57%, P = .006), 83% (95% CI = 68% to 98%, P<.001), and 66% (95% CI = 47% to 84%, P<.001), respectively, compared with vehicle, whereas a single dose of zoledronic acid decreased tumor burden by only 13% (95% CI = −2% to 28%, P = .84). Mice treated with a daily preventive regimen of clodronate or with a daily or weekly preventive regimen of zoledronic acid showed a decreased B02/GFP.2 cell tumor burden compared with vehicle, whereas a single preventive dose of zoledronic acid had no effect. Conclusion Daily or repeated intermittent therapy with clinical doses of bisphosphonates inhibits skeletal tumor growth in a mouse mode

Morphology and structure of YSZ powders: Comparison between xerogel and aerogel

Yttria-stabilized zirconia (YSZ) fine powders were prepared via sol–gel route in order to shape thermal barrier coatings (TBCs) from these powders. The main objective is to develop new undirectional coatings to allow best thermo-mechanical accommodations compared to conventional processes. To reach this aim, powders have to be able first to be highly dispersed into a sol (non-agglomeration, high specific surface area, etc.) and second to crystallize in the required metastable phase t0. Two routes have been used to dry gels: the conventional way which consists of simple evaporation of the solvent is compared to drying in supercritical conditions. Both YSZ powders after calcination at 950 8C of xerogel (Ex-xero-YSZ powder) and aerogel (Ex-aero-YSZ powder) crystallize in the tetragonal form. N2 adsorption/desorption analysis of the Ex-xero-YSZ powder indicates an Sw of 2.8 m2/g. For the Ex-aero-YSZ powder, the Sw (26 m2/g) is much higher than of Ex-xero-YSZ, leading to a better sintering capability. This high Sw is correlated to the small crystallite size (26 nm) and the alveolar morphology of Ex-aero-YSZ powders compared to Exxero-powder (49 nm). By reducing particles size and increasing the Sw of the powders, supercritical drying appears as a promising way to prepare stable slurries or loaded sols from fine YSZ particles for TBC applications. Indeed, after preparing nanometric powders, they are dispersed into a sol before shaping on superalloys substrates. After thermal treatment at 950 8C for 2 h which corresponds to the working temperature of TBC, the final aim will be to prepare ceramic YSZ coatings

HEDRINE (un nouvel outil d aide à la décision pour les interactions plante-médicament)

Lors de ce travail de thèse un nouvel outil a été mis en place pour l aide à la détection des interactions plante-médicament. Une base de données est dorénavant disponible sur le net à l adresse https://hedrine.ujf-grenoble.fr/. A ce jour, elle recense les interactions potentielles (via des interactions pharmacocinétiques ou pharmacodynamiques) ou démontrées lors d études cliniques ou de case reports entre des plantes médicinales et les médicaments anticancéreux listés dans la classe L du classement (ATC). Les interactions répertoriées sont toutes issues de la bibliographie internationale.GRENOBLE1-BU Médecine pharm. (385162101) / SudocSudocFranceF

Learning Output Embeddings in Structured Prediction

A powerful and flexible approach to structured prediction consists in embedding the structured objects to be predicted into a feature space of possibly infinite dimension by means of output kernels, and then, solving a regression problem in this output space. A prediction in the original space is computed by solving a pre-image problem. In such an approach, the embedding, linked to the target loss, is defined prior to the learning phase. In this work, we propose to jointly learn a finite approximation of the output embedding and the regression function into the new feature space. For that purpose, we leverage a priori information on the outputs and also unexploited unsupervised output data, which are both often available in structured prediction problems. We prove that the resulting structured predictor is a consistent estimator, and derive an excess risk bound. Moreover, the novel structured prediction tool enjoys a significantly smaller computational complexity than former output kernel methods. The approach empirically tested on various structured prediction problems reveals to be versatile and able to handle large datasets

Short fluorodeoxyuridine exposure of different human glioblastoma lines induces high-level accumulation of S-phase cells that avidly incorporate 125I-iododeoxyuridine

Purpose: Radio-iododeoxyuridine (IdUrd) is a potential Auger radiation therapy agent incorporated into DNA during the synthesis phase. In this study we sought to optimise S-phase targeting by modulating cellular cycling and radio-IdUrd DNA incorporation using short non-toxic fluorodeoxyuridine (FdUrd) incubations. Methods: Three human glioblastoma cell lines with different p53 expression were pre-treated with various FdUrd conditions. After different intervals, 125I-IdUrd DNA incorporation was measured. Fluorescence-activated cell sorter cell cycle analysis was performed after identical intervals post FdUrd pre-treatment. Results: The highest increase in 125I-IdUrd DNA incorporation was induced by 1-h incubation with 1μM FdUrd. Increase in radio-IdUrd DNA incorporation was greatest 16-24h after FdUrd, reaching factors of ≥7.5 over baseline incorporation in the three cell lines. Furthermore, cell synchronisation in S phase was observed with a peak of ≥69.5% in the three cell lines at 16 and 24h post FdUrd, corresponding to an increase of 2.5-4.1 over baseline. Conclusion: FdUrd-induced thymidine synthesis inhibition led to S-phase accumulation that was maximal after an interval of 16-24h and time-correlated with the highest radio-IdUrd DNA incorporation. These observations might allow the rational design of an Auger radiation therapy targeting a maximal number of S-phase cells in single treatment cycle

Protein-protein interaction network inference with semi-supervised Output Kernel Regression

National audienceIn this work, we address the problem of protein-protein interaction network inference as a semi-supervised output kernel learning problem. Using the kernel trick in the output space allows one to reduce the problem of learning from pairs to learning a single variable function with values in a Hilbert space. We turn to the Reproducing Kernel Hilbert Space theory devoted to vector- valued functions, which provides us with a general framework for output kernel regression. In this framework, we propose a novel method which allows to extend Output Kernel Regression to semi-supervised learning. We study the relevance of this approach on transductive link prediction using artificial data and a protein-protein interaction network of S. Cerevisiae using a very low percentage of labeled data