Supernovae, CMB, and Gravitational Leakage into Extra Dimensions

We discuss observational constraints coming from CMB and type Ia supernovae, for the model of accelerated universe produced by gravitational leakage into extra dimensions. Our fits indicate that the model is currently in agreement with the data. We also give the equations governing the evolution of cosmological perturbations. Future observations will be able to severely constrain the model.Comment: 20 pages, 6 figures, typos corrected and minor changes before publicatio

PPH dendrimers grafted on silica nanoparticles: surface chemistry, characterization, silver colloids hosting and antibacterial activity

Polyphosphorhydrazone (PPH) dendrimers have been grafted on silica nanoparticles, and the surface functions of the dendrimers have been derivatized to phosphonates with lateral poly(ethyleneglycol) (PEG) chains. All materials have been thoroughly characterized by MAS NMR, FT-IR, electron microscopy, TGA and elemental analysis. These materials successfully hosted silver and silver oxide nanoparticles. The resulting composites exhibit antibacterial activity

Momocs: Outline Analysis Using R

We introduce here Momocs, a package intended to ease and popularize modern morphometrics with R, and particularly outline analysis, which aims to extract quantitative variables from shapes. It mostly hinges on the functions published in the book entitled Modern Morphometrics Using R by Claude (2008). From outline extraction from raw data to multivariate analysis, Momocs provides an integrated and convenient toolkit to students and researchers who are, or may become, interested in describing the shape and its variation. The methods implemented so far in Momocs are introduced through a simplistic case study that aims to test if two sets of bottles have different shapes

ACES: Generating Diverse Programming Puzzles with Autotelic Language Models and Semantic Descriptors

Finding and selecting new and interesting problems to solve is at the heart of curiosity, science and innovation. We here study automated problem generation in the context of the open-ended space of python programming puzzles. Existing generative models often aim at modeling a reference distribution without any explicit diversity optimization. Other methods explicitly optimizing for diversity do so either in limited hand-coded representation spaces or in uninterpretable learned embedding spaces that may not align with human perceptions of interesting variations. With ACES (Autotelic Code Exploration via Semantic descriptors), we introduce a new autotelic generation method that leverages semantic descriptors produced by a large language model (LLM) to directly optimize for interesting diversity, as well as few-shot-based generation. Each puzzle is labeled along 10 dimensions, each capturing a programming skill required to solve it. ACES generates and pursues novel and feasible goals to explore that abstract semantic space, slowly discovering a diversity of solvable programming puzzles in any given run. Across a set of experiments, we show that ACES discovers a richer diversity of puzzles than existing diversity-maximizing algorithms as measured across a range of diversity metrics. We further study whether and in which conditions this diversity can translate into the successful training of puzzle solving models

Pesticide contamination interception strategy and removal efficiency in forest buffer and artificial wetland in a tile-drained agricultural watershed

Yves couqet : present adress : UMR7327 on sept. 2012International audiencePesticide pollution is a major threat to aquatic ecosystems that can be mitigated through complementary actions including buffer zones (BZs). This paper discusses the results of 3 yr of field-scale monitoring of the concentration and load transfer of 16 pesticides out of a tile-drained catchment (Bray, France) and their reduction through two BZ: an artificial wetland (AW) and a forest buffer (FB). Typically, the highest concentrations were measured in the first flows following pesticide applications or resuming after periods of low or no flow. An open/close water management strategy was implemented to operate the parallel BZ based on pesticide applications by the farmer. The strategy was efficient in intercepting molecules whose highest concentrations occurred during the first flows following application. Inlet vs. outlet pesticide load reductions ranged from 45% to 96% (AW) and from −32% to 100% (FB) depending on the pesticide molecule and the hydrological year. Partly reversible adsorption was a dominant process explaining pesticide removal; whereas, degradation occurred for sufficiently long water retention time. Apart from the least sorbing molecules (e.g., isoproturon), BZ can partially remove pesticide pollution

A competency-based model to bridge the gap between academic trainings and industrial trades

Within today's European socioeconomic context, supporting careers choices and occupational integration has become a major challenge. Education has to fit the changes of industry and job market, but this process requires a unified representation of professions and training programs. The competency concept appears to be a common vector, since it has turned to be a pervasive idea. Although industry has started specifying trades through competencies, similar attempts are not initiated for education yet. In this paper, we present a unifying model for training programs, professions and learners, built around competencies. Based on this model, several tools have been developed to help (1) educational teams to make sure that conceptions of curriculum fit the targeted learning objectives, (2) learners to make their careers choices through life easier, (3) industrial actors to identify training programs matching with their needs

Correlation between structural and optical properties of WO3 thin films sputter deposited by glancing angle deposition

International audienceTungsten oxide WO3 thin films are prepared by DC reactive sputtering. The GLancing Angle Deposition method (GLAD) is implemented to produce inclined columnar structures. The incident angle α between the particle flux and the normal to the substrate is systematically changed from 0 to 80°. For incident angles higher than 50°, a typical inclined columnar architecture is clearly produced with column angles β well correlated with the incident angle α according to conventional relationships determined from geometrical models. For each film, the refractive index and extinction coefficient are calculated from optical transmittance spectra of the films measured in the visible region. The refractive index at 589 nm drops from n589 = 2.18 down to 1.90 as α rises from 0 to 80°, whereas the extinction coefficient reaches k589 = 4.27 × 10−3 for an incident angle α = 80°, which indicates that the films produced at a grazing incident angle become more absorbent. Such changes of the optical behaviors are correlated with changes of the microstructure, especially a porous architecture, which is favored for incident angles higher than 50°. Optical band gap Eg, Urbach energy Eu and birefringence Δn617, determined from optical transmittance measurements, are also influenced by the orientation of the columns and their trend is discussed taking into account the disorder produced by the inclined particle flux

Modelling of a constructed wetland for pesticide mitigation

10 p.International audienceThe Water Framework Directive and the Ecophyto 2018 plan provides for measures against water chemical pollution. In the agricultural context, pesticide are a real stress for surrounding environment. Measures have been taken to reduce this stress, namely the reduction of chemical application, and the implantation of buffer zones like artificial wetland at the outlet of the agricultural watershed. A PhD thesis has begun in November 2012 on the modelling of the wetland functioning for pesticide mitigation. This work takes place in the team TAPAHS in the unit Hydrosystem and Bioprocesses of the Institute Irstea. The motivation of this work takes birth in the preceding studies of the team on the removal efficiency of a wetland regarding several pesticides. Several tools are yet available to reach our objectives. An experimental site has been instrumented in the city of Rampillon (France) and a state of art is under construction. The bibliography's study focus on two subjects: the tracer experiments and the constructed wetlands models which have been developed. These tools lead to a methodology which we propose to follow for the next steps of the PhD thesis

Une nouvelle approche pour la construction de classes de représentations non-linéaires de signaux

- Dans cet article nous proposons d'étendre le champ des représentations covariantes en appliquant préalablement au signal une transformation non-linéaire. Pour ce faire, nous reprenons l'approche proposée par Hlawatsch pour la construction des représentations linéaires et bilinéaires covariantes avec des opérateurs de déplacement. Nous montrons alors comment faire usage des noyaux de Mercer dans ce contexte, après un bref rappel sur les espaces de Hilbert à noyau reproduisant