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Global Null Controllability of the 1-Dimensional Nonlinear Slow Diffusion Equation

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Chinese Annals of Mathematics,Series B 2013年第3期34卷 333-344页

作者： jean-michel CORON Jesǘs Ildefonso DIAZ Abdelmalek DRICI Tommaso MINGAZZINI Institut Universitaire de France and Universit Pierre et Marie Curie (Paris 6) UMR 7598 Laboratoire Jacques-Louis Lions 4 place Jussieu F-75252 Paris cedex 5 France Universidad Complutense de Madrid Instituto de Matemtica Interdisiplinar and Dpto. de Matemtica Aplicada Plaza de las Ciencias 3 28040 Madrid Espaa Universit Pierre et Marie Curie (Paris 6) UMR 7598 Laboratoire Jacques-Louis Lions 4 place Jussieu F-75252 Paris cedex 5 France Universidad Complutense de Madrid Dpto. de Matemtica Aplicada Plaza de las Ciencias 3 28040 Madrid Espaa

The authors prove the global null controllability for the 1-dimensional nonlinear slow diffusion equation by using both a boundary and an internal control. They assume that the internal control is only time dependent. The proof relies on the return method in combination with some local controllability results for nondegenerate equations and rescaling techniques.

关键词： Nonlinear control Nonlinear slow diffusion equation Porous mediumequation

A SEM-based method to determine the mineralogical composition and the particle size distribution of suspended sediment

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International Journal of Sediment Research 2019年第2期34卷 85-94页

作者： Sylvain Pinet Bruno Lartiges jean-michel Martinez Sylvain Ouillonc University of Toulouse (Paul Sabatier) Geosciences Environment ToulouseCNRS(Centre National de la Recherche Scientifique)IRD(Institut de Recherche pour le Développement) Instituto de Geosciencias Universidade de BrasiliaCampus Universitario Darcy RibeiroICC Centro University of Toulouse LEGOS(Laboratoire d'Etudes en Géophysique et Océanographie Spatiales)

A robust method for characterizing the mineralogy of suspended sediment in continental rivers is *** encompasses 3 steps:the filtration of a few milliliters of water,measurements of X-ray energy dispersive spectra using Scanning Electron Microscopy(SEM),and robust machine learning tools of *** method is applied to suspended particles collected from various Amazonian rivers.A total of more than 204,000 particles were analyzed by SEM-EDXS(Energy Dispersive X-ray Spectroscopy),*** 15,700 particles per sampling station,which lead to the identification of 15 distinct groups of mineralogical *** size distribution of particles collected on the filters was derived from the SEM micrographs taken in the backscattered electron imaging mode and analyzed with ImageJ *** determination of the main mineralogical groups composing the bulk sediment associated with physical parameters such as particle size distribution or aspect ratio allows a precise characterization of the load of the terrigenous particles in rivers or *** the case of the Amazonian rivers investigated,the results show that the identified mineralogies are consistent with previous studies as well as between the different samples *** method enabled the evolution of grain size distribution from fine to coarse material to be described in the water *** about hydrodynamic sorting of mineral particles in the water column are also briefly *** proposed method appears well suited for intensive routine monitoring of suspended sediment in river systems.

关键词： Mineralogy Scanning Electron Microscopy Suspended sediment Machine learning Particle size distribution

Peripheral nerve regeneration and intraneural revascularization

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Neural Regeneration Research 2019年第1期14卷 24-33页

作者： Martial Caillaud Laurence Richard jean-michel Vallat Alexis Desmoulière Fabrice Billet University of Limoges Myelin Maintenance and Peripheral Neuropathies Faculties of Medicine and Pharmacy University Hospital of Limoges Department of Neurology "Reference Center for Rare Peripheral Neuropathies" Department of Neurology

Peripheral nerves are particularly vulnerable to injuries and are involved in numerous pathologies for which specific treatments are lacking. This review summarizes the pathophysiological features of the most common traumatic nerve injury in humans and the different animal models used in nerve regeneration studies. ~Ihe current knowledge concerning Wallerian degeneration and nerve regrowth is then described. Finally, the involvement of intraneural vascularization in these processes is addressed. As intraneural vascularization has been poorly studied, histological experiments were carried out from rat sciatic nerves damaged by a glycerol injection. The results, taken together with the data from literature, suggest that revascularization plays an important role in peripheral nerve regeneration and must therefore be studied more carefully.

关键词： compression crush transection Sunderland's classification Wallerian degeneration angiogenesis traumatic glycerol

Evaluation of bias on the assessment of diet breadth of herbivorous insects using molecular methods

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Insect Science 2017年第2期24卷 194-209页

作者： Gissela De la Cadena Anna Papadopoulou jean-michel Maes Jesus Gomez-Zurita Animal Biodiversity and Evolution Institut de Biologia Evolutiva (CSIC-Univ. Pompeu Fabra) Barcelona Spain Department of Integrative Ecology Estacion Biologica de Donana (EBD-CSIC) Seville Spain Museo entomologico de Leon Leon Nicaragua

The interactions between herbivores and their host plants play a key role in ecological processes. Understanding the width and nature of these interactions is funda- mental to ecology and conservation. Recent research on DNA-based inference of trophic associations suggests that the host range of phytophagous insects in the tropics may be wider than previously thought based on traditional observation. However, the reliability of molecular inference of ecological associations, still strongly dependent on PCR and thus exposed to the risk of contamination with environmental DNA, is under debate. Here, we explored alternative procedures to reduce the chance of amplification of external, nondiet DNA, including surface decontamination and analysis of mid/hind guts, comparing the results with those obtained using the standard protocol. We studied 261 specimens in eight species of Neotropical Chrysomelidae that yielded 316 psbA-trnH intergenic spacer sequences （cpDNA marker of putative diets） from unique and multiple-band PCR results. The taxonomic identity of these sequences was inferred using the automated pipeline BAGpipe, yielding results consistent with 31 plant families. Regardless of the proto- col used, a wide taxonomic spectrum of food was inferred for all chrysomelid species. Canonical Correspondence Analysis using these data revealed significant differences at- tributed mainly to species （expectedly, since they represent different ecologies）, but also to treatment （untreated vs. cleaned/gut samples） and PCR results （single vs. multiple bands）. Molecular identification of diets is not straightforward and, regardless of the species＇ niche breadth, combining approaches that reduce external contamination and studying multiple individuals per species may help increasing confidence in results.

关键词： food-webs gut content insect plant interaction molecular ecology molec-ular taxonomy psbA-trnH intergenic spacer

Distribution of trace metals and Pb isotopes in bottom sediments of the Murucupi River,North Brazil

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International Journal of Sediment Research 2016年第3期31卷 226-236页

作者： Diomar Cavalcante Oliveira jean michel Lafon Marcelo de Oliveira Lima Institute of Geosciences Federal University of Pára Environmental Section Evandro Chagas Institute

The Murucupi River belongs to the hydrographic network of the Para River estuary,at the southern portion of the Amazon River mouth,which consists of a fluvial-marine transitional zone under strong impact of both tidal and fluvial *** geochemical results obtained for bottom sediments from the Murucupi River,the Arrozal Channel,and the Para River indicate a natural variation of Pb,Cr,Cu,Zn,and Ni content among these water ways with no significant anthropogenic *** to the threshold effects level(TEL),the contents of trace metals do not offer risk to the local *** contrast,the differences in the Pb isotopic composition of sediments in the Murucupi River,the Arrozal Channel,and the Para River are *** isotopic signatures indicate an anthropogenic contribution of Pb in the Murucupi River originating from the domestic effluents of urban centers;industrial waste represented by red mud is not *** results demonstrate that the Pb isotopic signature is a prospective indicator for future contamination of bottom sediments by trace metals and is useful for identifying contaminants among the possible anthropogenic sources.

关键词： Bottom sediments Pb isotopes Trace metals Murucupi River Barcarena

Super-low friction of ta-C coating in presence of oleic acid

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Friction 2014年第2期2卷 156-163页

作者： Makoto KANO jean michel MARTIN Kentaro YOSHIDA Maria Isabel DE BARROS BOUCHET Division of Mechanical&Material Engineering Kanagawa Industrial Technology Center705-1 Shimo-ImaizumiEbinaKanagawaJapan LTDS Ecole Centrale de Lyon 69380EcullyFrance

Friction tests have been carried out on bearing steel friction pairs coated with a-C:H and ta-C under lubricated conditions with 1-hexadecene and pure oleic acid,*** results show that ta-C leads to the super-low regime with oleic acid(friction coefficient below 0.01)and that a-C:H is quite well lubricated by *** analyses by coupling X-ray photoelectron spectroscopy(XPS)and secondary ion mass spectrometry(SIMS)have been carried out in the case of oleic acid with ta-C and a-C:H *** show that tribochemical reactions have *** groups terminate the ta-C surface whereas a-C:H is covered by a thin tribofilm and is terminated by oleic acid *** superlow regime in the case of ta-C is mainly attributed to the presence of the OH-termination.

关键词： epoxy composite short carbon fiber friction wear

Vegetation-based bioindication of humus forms in coniferous mountain forests

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Journal of Mountain Science 2017年第4期14卷 662-673页

作者： Kerstin ANSCHLAG Dylan TATTI Niels HELLWIG Giacomo SARTORI jean-michel GOBAT Gabriele BROLL Institute of Geography University of OsnabrueckSeminarstrafte 19ab49074 OsnabrueckGermany Functional Ecology Laboratory University of NeuchatelRue Emile-Argand 112000 NeuchatelSwitzerland School of Agricultural Forest and Food Sciences HAFLBern University of Applied SciencesLanggasse 853052 ZollikofenSwitzerland MUSE Corso del Lavoro e della Scienza 338122 TrentoItaly

Humus forms, especially the occurrence and the thickness of the horizon of humified residues （OH）, provide valuable information on site conditions. In mountain forest soils, humus forms show a high spatial variability and data on their spatial patterns is often scarce. Our aim was to test the applicability of various vegetation features as proxy for OH thickness. Subalpine coniferous forests dominated by Picea abies （L.） H. Karst. and Larix decidua Mill. were studied in the Province of Trento, Italian Alps, between ca. 900 and 22o0 m a.s.1. Braun-Blanquet vegetation relevds and OH thickness were recorded at 152 plots. The vegetation parameters, tested for their suitability as indicators of OH thickness, encompassed mean Landolt indicator values of the herb layer （both unweighted and cover-weighted means） as well as parameters of vegetation structure （cover values of plant species groups） calculated from the releves. To our knowledge, the predictive power of Landolt indicator values （LIVs） for humus forms had not been tested before. Correlations between OHthickness and mean LIVs were strongest for the soil reaction value, but indicator values for humus, nutrients, temperature and light were also significantly correlated with OH thickness. Generally, weighting with species cover reduced the indicator quality of mean LIVs for OH thickness. The strongest relationships between OH thickness and vegetation structure existed in the following indicators： the cover of forbs （excluding graminoids and ferns） and the cover of Erieaeeae in the herb layer. Regression models predicting OH thickness based on vegetation structure had almost as much predictive power as models based on LIVs. We conclude that LIVs analysis can produce fairly reliable information regarding the thickness of the OH horizon and, thus, the humus form. If no releve data are readily available, a field estimation of the cover values of certain easily distinguishable herb layer species groups is much faster than

关键词： Landolt indicator values OH horizon Forest ecosystem Montane forest, Italian Alps

Influence of working gas pressure on the performance of W/Si multilayers

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Chinese Physics C 2012年第9期36卷 909-914页

作者：王芳芳朱京涛钟奇王占山 Philippe Jonnard Karine Le Guen jean-michel André michel Fialin Institute of Precision Optical Engineering Department of PhysicsTongji University Laboratoire Chimie Physique-Matière Rayonnement UPMC Univ Paris 06CNRS UMR 761411 rue Pierre et Marie CurieF-75231 Paris Cedex 05France Centre CAMPARIS CNRS UMR 7154campus Jussieu4 place JussieuF-75254 Paris Cedex 05France

The effect of Ar pressure on the performance of W/Si multilayers is investigated. W/Si multilayers were deposited by a high vacuum DC magnetron sputtering system. The Ar pressure was changed from 1.0 to 5.0 mTorr with an interval of 1.0 mTorr during the deposition process. Electron probe microanalysis and Rutherford backscattering are performed to determine the Ar content incorporated within these multilayers. The results demonstrate that less Ar is incorporated within the sample when more Ar is used in the plasma, which could be explained by the increase of the collision probability and the decrease in the kinetic energy of Ar ions arriving at the substrate when more Ar exists. The grazing incident X-ray reflectivity （GIXR） at 0.154 nm is used to determine the structural parameters of the layers. The results show that the structures of these multilayers prepared at different Ar pressure are very similar and that the interface roughness increases quickly when the Ar pressure is higher than 3.0 mTorr. The measurements of the extreme ultraviolet （EUV） reflectivity indicate that the reflectivity decreases when Ar pressure increases. The fitting results of GIXR and EUV refiectivity curves indicate that with an increase of Ar pressure, the density and decrement of the refractive index are increased for W and decreased for Si, which is mainly due to （1） the decrease in Ar content incorporated within these multilayers which affects their performance and （2） the increase of collision probability for sputtered W and Si, the decrease of their average kinetic energy arriving at the substrate, and thus the loosing of their layers.

关键词： multilayer deposition working pressure EPMA RBS reflectivity

Lattice Boltzmann Modeling of Miscible Multicomponent Gas Mixtures in the Rarefied Regime

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Communications in Computational Physics 2022年第9期32卷 1179-1216页

作者： michel Ho Sami Ammar Sebastien Leclaire Marcelo Reggio jean-Yves Trepanier Departement of Mechanical Engineering Polytechnique Montreal2500 Chemin de PolytechniqueMontreal H3T 1J4Canada

An extension to rarefied flow regimes of the lattice Boltzmann methodbased model for miscible mixtures developed by Vienne et al.(Physical Review E 100.2(2019):023309)is *** model is applied to study the gas phase separation phenomenon in mixture flows that traditional macroscopic approaches fail to *** extension includes a wall function approach with an empirical coefficient to define an effectivemean free path in solid geometries,which locally defines the kinematic viscosity and binary diffusion *** algorithm is also modified by a local multi-relaxation time collision operator and slip boundary conditions at solid *** mixture flow simulations are conducted through a 2D plane microchannel within the slip and early transition flow *** a miscible gaseous phase,the mixture loses its homogeneity and independent velocity profiles for each component are observed in the rarefied regime and captured with the current *** addition,the gas separation phenomenon increases with the rarefaction rate and the molecular mass *** individual treatment of the species within mixture flows in the developed lattice Boltzmann model helps understanding the increasing independent behavior of the individual specieswithin themixture as the regime becomesmore rarefied.

关键词： Lattice Boltzmann gaseous mixtures rarefied regimes