16 research outputs found

    Development of intermediate layer systems for direct deposition of thin film solar cells onto low cost steel substrates

    Get PDF
    The functionalisation of low-cost steel over large areas with low cost intermediate layers (ILs) for utilisation as substrates in thin film solar modules is reported. Three approaches for the deposition of ILs are demonstrated and evaluated; a thick SiOx sol–gel based on a one-step acidic catalysis applied by spray technique, a commercial screen-printable dielectric ink, and an epoxy-based material (SU8) deposited by screen printing or bar coating. These ILs demonstrated the properties of surface levelling (quantified by mechanical profilometry), electric insulation (tested using breakdown voltage and leakage current) and acted as an anti-diffusion barrier (demonstrated with glow discharge mass spectrometry). Moreover, the performances of amorphous silicon (a-Si:H) and organic photovoltaic (OPV) thin film solar cells grown on carbon and stainless steels (a-Si:H: 5.53% and OPV: 2.40%) show similar performances as those obtained using a reference glass substrate (a-Si:H: 5.51% and OPV: 2.90%). Finally, a cost analysis taking into account both the SiOx sol–gel and the dielectric ink IL was reported to demonstrate the economic feasibility of the steel/IL prototypes

    Intranasal (R, S)-ketamine delivery induces sustained antidepressant effects associated with changes in cortical balance of excitatory/inhibitory synaptic activity

    No full text
    International audienceIn 2019, an intranasal (IN) spray of esketamine SPRAVATO® was approved as a fast-acting antidepressant by drug Agencies US FDA and European EMA. At sub-anesthetic doses, (±)-ketamine, a non-competitive glutamate N-methyl-D-aspartate (NMDA) receptor antagonist, increases the overall excitability of the medial prefrontal cortex (mPFC), an effect being essential for its rapid antidepressant activity. We wondered if this effect of ketamine could come from changes in the balance between neuronal excitation and inhibition (E/I balance) in the mPFC. Here, we performed a preclinical approach to study neurochemical and behavioral responses to a single IN ketamine dose in BALB/cJ mice, a strain more sensitive to stress. By using in vivo microdialysis, we measured cortical E/I balance as the ratio between glutamate to GABA extracellular levels 24 h post-ketamine. We found, for the first time, that E/I balance was shifted in favor of excitation rather than inhibition in the mPFC but more robustly with IN KET than with a single intraperitoneal (IP) dose. Increases in plasma and brain ketamine, norketamine and HNKs levels suggest different metabolic profiles of IP and IN ketamine 30 min post-dose. A significantly larger proportion of ketamine and HNKs in the brain are derived from the IN route 30 min post-dose. It may be linked to the greater magnitude in E/I ratio following IN delivery relative to IP at t24 h. This study suggests that both IP and IN are effective brain delivery methods inducing similar sustained antidepressant efficacy of KET, but the way they induced neurotransmitter changes is slightly different

    Impacts interculturels au Néolithique moyen. Du terroir au territoire : sociétés et espaces

    No full text
    Le 25e colloque interrégional sur le Néolithique a rassemblé plus de 200 chercheurs les 20 et 21 octobre 2001 à l'Université de Bourgogne à Dijon. Le présent volume d'actes regroupe les différentes contributions de cette manifestation à laquelle participaient de nombreux néolithiciens des pays limitrophes. Leur présentation et les débats ont été centrés sur deux thèmes, tout en laissant la place à quelques exposés relevant de l'actualité de la recherche. Impacts interculturels entre groupes du Néolithique moyen. Dix contributions sont consacrées à ce thème qui vise à caractériser et à évaluer les impacts interculturels entre groupes pendant une période où se constate une évolution graduelle vers des sociétés organisées plus hiérarchisées. On assiste durant ces temps à un fort développement des échanges et des influences, voire à des phénomènes que l'on pourrait qualifier de supra-culturels. Groupes néolithiques et maîtrise des espaces. Huit communications sont présentées dans ce cadre qui aurait pu s'intituler « du terroir au territoire : sociétés et espaces ». Ces approches, d'ordre spatial, ont été abordées sous trois angles : l'analyse de terroirs, la géographie culturelle et l'étude des territoires (emprises, occupation des sols, marques identitaires, témoins d'appropriation). Actualité de la recherche et approches méthodologiques. Sous ces deux rubriques sont respectivement rassemblées sept communications touchant des découvertes récentes et deux consacrées à des technologies ou disciplines appliquées à l'archéologie (paléogénétique et technologie céramique)

    FRIPON: A worldwide network to track incoming meteoroids

    No full text
    Context. Until recently, camera networks designed for monitoring fireballs worldwide were not fully automated, implying that in case of a meteorite fall, the recovery campaign was rarely immediate. This was an important limiting factor as the most fragile - hence precious - meteorites must be recovered rapidly to avoid their alteration. Aims. The Fireball Recovery and InterPlanetary Observation Network (FRIPON) scientific project was designed to overcome this limitation. This network comprises a fully automated camera and radio network deployed over a significant fraction of western Europe and a small fraction of Canada. As of today, it consists of 150 cameras and 25 European radio receivers and covers an area of about 1.5 × 106km2. Methods. The FRIPON network, fully operational since 2018, has been monitoring meteoroid entries since 2016, thereby allowing the characterization of their dynamical and physical properties. In addition, the level of automation of the network makes it possible to trigger a meteorite recovery campaign only a few hours after it reaches the surface of the Earth. Recovery campaigns are only organized for meteorites with final masses estimated of at least 500 g, which is about one event per year in France. No recovery campaign is organized in the case of smaller final masses on the order of 50 to 100 g, which happens about three times a year; instead, the information is delivered to the local media so that it can reach the inhabitants living in the vicinity of the fall. Results. Nearly 4000 meteoroids have been detected so far and characterized by FRIPON. The distribution of their orbits appears to be bimodal, with a cometary population and a main belt population. Sporadic meteors amount to about 55% of all meteors. A first estimate of the absolute meteoroid flux (mag < -5; meteoroid size ≥∼1 cm) amounts to 1250/yr/106km2. This value is compatible with previous estimates. Finally, the first meteorite was recovered in Italy (Cavezzo, January 2020) thanks to the PRISMA network, a component of the FRIPON science project

    FRIPON: a worldwide network to track incoming meteoroids

    No full text
    (IF 5.80; Q1)International audienceContext. Until recently, camera networks designed for monitoring fireballs worldwide were not fully automated, implying that in case of a meteorite fall, the recovery campaign was rarely immediate. This was an important limiting factor as the most fragile-hence precious-meteorites must be recovered rapidly to avoid their alteration. Aims. The Fireball Recovery and InterPlanetary Observation Network (FRIPON) scientific project was designed to overcome this limitation. This network comprises a fully automated camera and radio network deployed over a significant fraction of western Europe and a small fraction of Canada. As of today, it consists of 150 cameras and 25 European radio receivers and covers an area of about 1.5 × 10 6 km 2. Methods. The FRIPON network, fully operational since 2018, has been monitoring meteoroid entries since 2016, thereby allowing the characterization of their dynamical and physical properties. In addition, the level of automation of the network makes it possible to trigger a meteorite recovery campaign only a few hours after it reaches the surface of the Earth. Recovery campaigns are only organized for meteorites with final masses estimated of at least 500 g, which is about one event per year in France. No recovery campaign is organized in the case of smaller final masses on the order of 50 to 100 g, which happens about three times a year; instead, the information is delivered to the local media so that it can reach the inhabitants living in the vicinity of the fall. Results. Nearly 4000 meteoroids have been detected so far and characterized by FRIPON. The distribution of their orbits appears to be bimodal, with a cometary population and a main belt population. Sporadic meteors amount to about 55% of all meteors. A first estimate of the absolute meteoroid flux (mag <-5; meteoroid size ≥∼1 cm) amounts to 1250/yr/10 6 km 2. This value is compatible with previous estimates. Finally, the first meteorite was recovered in Italy (Cavezzo, January 2020) thanks to the PRISMA network, a component of the FRIPON science project
    corecore