Fan noise analysis using a microphone array

The purpose of this paper is to show the capabilities of MicrodB's acoustic imagery algorithm to characterize rotating sources. First part will explain the main specificity of the treatment. In the second part, possibilities of analysis and validations on simple tests will be demonstrated. In the last part, an industrial application will be studied : a Technofan extract fan with a 10000 RPM rotational speed will be analysed. Both fixed and rotating sources will be separated, allowing the localization of rotating sources on the blades

Software-hardware Integration and Human-centered Benchmarking for Socially-compliant Robot Navigation

The social compatibility (SC) is one of the most important parameters for service robots. It characterises the interaction quality between a robot and a human. In this paper, we first introduce an open-source software-hardware integration scheme for socially-compliant robot navigation and then propose a human-centered benchmarking framework. For the former, we integrate one 3D lidar, one 2D lidar, and four RGB-D cameras for robot exterior perception. The software system is entirely based on the Robot Operating System (ROS) with high modularity and fully deployed to the embedded hardware-based edge while running at a rate that exceeds the release frequency of sensor data. For the latter, we propose a new human-centered performance evaluation metric that can be used to measure SC quickly and efficiently. The values of this metric correlate with the results of the Godspeed questionnaire, which is believed to be a golden standard approach for SC measurements. Together with other commonly used metrics, we benchmark two open-source socially-compliant robot navigation methods, in an end-to-end manner. We clarify all aspects of the benchmarking to ensure the reproducibility of the experiments. We also show that the proposed new metric can provide further justification for the selection of numerical metrics (objective) from a human perspective (subjective).Comment: 8 pages, 8 figure

Zirconocene-catalyzed stereoselective cyclocopolymerization of 2-methyl-1,5-hexadiene with propylene

International audienceThe copolymerization of 2-methyl-1,5-hexadiene (MHD) with propylene has been studied with different single-site group 4 metal catalysts. Systems based on ansa-zirconocene precursors such as rac-{Me2Si(2-Me-4-Ph-Ind}ZrCl2 (1) and C1- or CS-symmetric ansa-{CpCR2Flu}ZrCl2 (2 and 3, respectively), once activated by MAO, are highly active (20–600 kgpol gcat−1 h−1 at 60–70 °C) and yield copolymers in which MHD is cyclopolymerized as methylene-(1-methyl)-1,3-cyclopentane (MMCP) units. 13C NMR studies revealed, depending on the symmetry of the precatalyst used, either highly isotactic (1, 2) or syndiotactic (3) polypropylene (PP) backbones, with isolated MMCP units. Fully trans-diastereoselective cyclopolymerization of MHD was observed with 1/MAO, while a mixture of trans and cis MMCP rings was observed with 2 and 3/MAO. The amount of MMCP units in PP (0.2–1.6 mol%) can be controlled by the amount of MHD in the feed. In contrast, the constrained geometry catalyst system based on {C5Me4SiMe2NtBu}TiCl2 (4) and MAO showed a much lower productivity (ca. 3 kgpol gcat−1 h−1 at 60 °C) and yielded a regioirregular, atactic copolymer in which MHD is simply vinyl-inserted in quite moderate amounts (0.2 mol%)

NO signaling functions in the biotic and abiotic stress responses

In the last 1990s, NO became an increasingly popular target of investigation in plants. As in mammals, NO fulfils a broad spectrum of signalling functions in pathophysiological processes in plants. Here we summarize studies published in recent years that provide novel insights into the signalling functions of NO produced by plant cells exposed to abiotic stresses and biotic stress (pathogen-derived elicitors). Particularly, we report that NO emerges as a key messenger governing the overall control of Ca2+ homeostasis. Although the precise signalling functions of NO are poorly understood, its capacity to modulate Ca2+ homeostasis provides an extraordinary and remarkable effective way of conveying information

Protein S-nitrosylation: specificity and identification strategies in plants

The role of nitric oxide (NO) as a major regulator of plant physiological functions has become increasingly evident. To further improve our understanding of its role, within the last few years plant biologists have begun to embrace the exciting opportunity of investigating protein S-nitrosylation, a major reversible NO-dependent post-translational modification (PTM) targeting specific Cys residues and widely studied in animals. Thanks to the development of dedicated proteomic approaches, in particular the use of the Biotin Switch Technique (BST) combined with mass spectrometry, hundreds of plant protein candidates for S-nitrosylation have been identified. Functional studies focused on specific proteins provided preliminary comprehensive views of how this PTM impacts the structure and function of proteins and, more generally, of how NO might regulate biological plant processes. The aim of this review is to detail the basic principle of protein S-nitrosylation, to provide information on the biochemical and structural features of the S-nitrosylation sites and to describe the proteomic strategies adopted to investigate this PTM in plants. Limits of the current approaches and tomorrow's challenges are also discussed

Evidence that a common arbuscular mycorrhizal network alleviates phosphate shortage in interconnected walnut sapling and maize plants

Under agroforestry practices, inter-specific facilitation between tree rows and cultivated alleys occurs when plants increase the growth of their neighbors especially under nutrient limitation. Owing to a coarse root architecture limiting soil inorganic phosphate (Pi) uptake, walnut trees (Juglans spp.) exhibit dependency on soil-borne symbiotic arbuscular mycorrhizal fungi that extend extra-radical hyphae beyond the root Pi depletion zone. To investigate the benefits of mycorrhizal walnuts in alley cropping, we experimentally simulated an agroforestry system in which walnut rootstocks RX1 (J. regia x J. microcarpa) were connected or not by a common mycelial network (CMN) to maize plants grown under two contrasting Pi levels. Mycorrhizal colonization parameters showed that the inoculum reservoir formed by inoculated walnut donor saplings allowed the mycorrhization of maize recipient roots. Relative to non-mycorrhizal plants and whatever the Pi supply, CMN enabled walnut saplings to access maize Pi fertilization residues according to significant increases in biomass, stem diameter, and expression of JrPHT1;1 and JrPHT1;2, two mycorrhiza-inducible phosphate transporter candidates here identified by phylogenic inference of orthologs. In the lowest Pi supply, stem height, leaf Pi concentration, and biomass of RX1 were significantly higher than in non-mycorrhizal controls, showing that mycorrhizal connections between walnut and maize roots alleviated Pi deficiency in the mycorrhizal RX1 donor plant. Under Pi limitation, maize recipient plants also benefited from mycorrhization relative to controls, as inferred from larger stem diameter and height, biomass, leaf number, N content, and Pi concentration. Mycorrhization-induced Pi uptake generated a higher carbon cost for donor walnut plants than for maize plants by increasing walnut plant photosynthesis to provide the AM fungus with carbon assimilate. Here, we show that CMN alleviates Pi deficiency in co-cultivated walnut and maize plants, and may therefore contribute to limit the use of chemical P fertilizers in agroforestry systems