89 research outputs found
Caractérisation et amélioration de la testabilité séquentielle pseudo-aléatoire des circuits VLSI
A pile-up of edge dislocations to relax Misfit strain
It is shown that very large stresses may be present in the thin films that comprise integrated circuits and magnetic disks and that these stresses can cause deformation and fracture of the material. For a crystalline film on a non-deformable substrate, a key problem involves the movement of dislocations in the thin film. An analysis of this problem provides insight into both the formation of misfit dislocations in epitaxial thin films and the high strengths of thin metal films on substrates. We develop in this paper, theoretical calculations for dislocation nucleation phenomena in nanomaterials obtained by hetero-epitaxial growth of thin films on substrates having lattice mismatch defects. Atomic force microscopy observations showed the nucleation of dislocations from free lateral surfaces to relax the "misfit" strain, here we explain the principle of nucleating edge dislocations from these surfaces by the theoretical calculation, using the method of image stress and energy study. We begin, by treating the case of a single dislocation and then generalize the work at a pile-up of n interface dislocations.
Nasal extranodal peripheral NK/T-cell lymphoma treated by the protocol NK/T-cell high-dose-methotrexate L-asparaginase dexamethasone
Unpublished Mediterranean records of marine alien and cryptogenic species
Good datasets of geo-referenced records of alien species are a prerequisite for assessing the spatio-temporal dynamics of biological invasions, their invasive potential, and the magnitude of their impacts. However, with the exception of first records on a country level or wider regions, observations of species presence tend to remain unpublished, buried in scattered repositories or in the personal databases of experts. Through an initiative to collect, harmonize and make such unpublished data for marine alien and cryptogenic species in the Mediterranean Sea available, a large dataset comprising 5376 records was created. It includes records of 239 alien or cryptogenic taxa (192 Animalia, 24 Plantae, 23 Chromista) from 19 countries surrounding the Mediterranean Sea. In terms of records, the most reported Phyla in descending order were Chordata, Mollusca, Chlorophyta, Arthropoda, and Rhodophyta. The most recorded species was Caulerpa cylindracea, followed by Siganus luridus, Magallana sp. (cf. gigas or angulata) and Pterois miles. The dataset includes records from 1972 to 2020, with the highest number of records observed in 2018. Among the records of the dataset, Dictyota acutiloba is a first record for the Mediterranean Sea. Nine first country records are also included: the alga Caulerpa taxifolia var. distichophylla, the cube boxfish Ostracion cubicus, and the cleaner shrimp Urocaridella pulchella from Israel; the sponge Paraleucilla magna from Libya and Slovenia; the lumpfish Cyclopterus lumpus from Cyprus; the bryozoan Celleporaria vermiformis and the polychaetes Prionospio depauperata and Notomastus aberans from Malta
Collaborative Database to Track Mass Mortality Events in the Mediterranean Sea
Anthropogenic climate change, and global warming in particular, has strong and increasing impacts on marine ecosystems (Poloczanska et al., 2013; Halpern et al., 2015; Smale et al., 2019). The Mediterranean Sea is considered a marine biodiversity hot-spot contributing to more than 7% of world's marine biodiversity including a high percentage of endemic species (Coll et al., 2010). The Mediterranean region is a climate change hotspot, where the respective impacts of warming are very pronounced and relatively well documented (Cramer et al., 2018). One of the major impacts of sea surface temperature rise in the marine coastal ecosystems is the occurrence of mass mortality events (MMEs). The first evidences of this phenomenon dated from the first half of'80 years affecting the Western Mediterranean and the Aegean Sea (Harmelin, 1984; Bavestrello and Boero, 1986; Gaino and Pronzato, 1989; Voultsiadou et al., 2011). The most impressive phenomenon happened in 1999 when an unprecedented large scale MME impacted populations of more than 30 species from different phyla along the French and Italian coasts (Cerrano et al., 2000; Perez et al., 2000). Following this event, several other large scale MMEs have been reported, along with numerous other minor ones, which are usually more restricted in geographic extend and/or number of affected species (Garrabou et al., 2009; Rivetti et al., 2014; MarbĂ et al., 2015; Rubio-Portillo et al., 2016, authors' personal observations). These events have generally been associated with strong and recurrent marine heat waves (Crisci et al., 2011; Kersting et al., 2013; Turicchia et al., 2018; Bensoussan et al., 2019) which are becoming more frequent globally (Smale et al., 2019). Both field observations and future projections using Regional Coupled Models (Adloff et al., 2015; Darmaraki et al., 2019) show the increase in Mediterranean sea surface temperature, with more frequent occurrence of extreme ocean warming events. As a result, new MMEs are expected during the coming years. To date, despite the efforts, neither updated nor comprehensive information can support scientific analysis of mortality events at a Mediterranean regional scale. Such information is vital to guide management and conservation strategies that can then inform adaptive management schemes that aim to face the impacts of climate change.MV-L was supported by a postdoctoral contract Juan de la Cierva-IncorporaciĂłn (IJCI-2016-29329) of Ministerio de Ciencia, InnovaciĂłn y Universidades. AI was supported by a Technical staff contract (PTA2015-10829-I) Ayudas Personal TĂ©cnico de Apoyo of Ministerio de EconomĂa y Competitividad (2015). Interreg Med Programme (grant number Project MPA-Adapt 1MED15_3.2_M2_337) 85% cofunded by the European Regional Development Fund, the MIMOSA project funded by the Foundation Prince Albert II Monaco and the European Union's Horizon 2020 research and innovation programme under grant agreement no 689518 (MERCES). DG-G was supported by an FPU grant (FPU15/05457) from the Spanish Ministry of Education. J-BL was partially supported by the Strategic Funding UID/Multi/04423/2013 through national funds provided by FCT - Foundation for Science and Technology and European Regional Development Fund (ERDF), in the framework of the programme PT2020
Etude des magmatismes leucogranitique et ongonitique de Blond (Haut Limousin-Massif Central Français). Relations avec une mise en place syntectonique du massif granitique.
Two distinct magmatic evolutions coexist at Blond, namely the leucogranitic and the ongonitic magmatisms, leading to a complete revision of the known pattern of this Variscan part of the northwestern French Massif Central. Examination of topaz features within the albite and topaz facies provides a typological classification based upon the relationships between habits, chemical composition, and the genesis conditions of this mineral. As such, within the Blond ongonites, topaz composition lies entirely within the space defined by natural F-OH topaz solid solution series at moderate pressures and confirms the existence of two generations of magmatic topaz (early-stage OH-rich topaz and late stage F-rich topaz). These typologic peculiarities could be related to high HF concentration in the melt, while the effect of temperature on the F-content of topaz as it was demonstrated experimentally can be reviewed. Analysis of Li-muscovites showed a chemical equilibrium between different fluorine-bearing minerals and suggested a F-, Li-, W-, HREE- and other trace elements-rich fluid phase separation from the melt.The structural petrology data obtained through the field-based study and microstructural analyses on samples methodically oriented provide an example of interference between diapiric rise and regional shearing. In fact, structures and microstructures recorded at Blond are consistent with a syntectonic emplacement of the granitic massif, coeval with Oradour dextral strike-slip fault. During this Stephanian deformation, submeridian shortening stress developped a conjugate ENE-WSWsinistral shear system and resulted in the formation at the viscous state of directed shear corridors, which in turn induced the ongonitic magma emplacement, associated with a network of wolframite-quartz veins.At Blond, Li- and Fe-rich micas display microstructural evidence of syntectonic recrystallization, allowing us to define, by indexing the mineral orientation, geochemical records of four superimposed magmatic planar fabrics, as well as their succession. Geochemical evolution of Li-Fe micas is assigned to both the andalusite destabilisation as a potential provider of Al and Si, and the late circulation of Li and F in the Blond felsic magma. The formation conditions of andalusite paragenesis indicate a depth of ~12 km. Moreover, the study of plastic deformation of quartz confirms the main data concluded for the Blond granitic massif.Deux Ă©volutions magmatiques continues cohabitent Ă Blond et conduisent Ă une rĂ©vision de fond en comble du schĂ©ma connu de cette portion hercynienne du Nord-Ouest du Massif Central Français. Le premier magmatisme peralumineux : magmatisme leucogranitique, de provenance profonde suit un processus de diffĂ©renciation par cristallisation fractionnĂ©e. MenĂ©e Ă son terme, cette Ă©volution donne naissance Ă un deuxiĂšme magmatisme Ă albite et topaze : magmatisme ongonitique. SubdivisĂ© en deux variĂ©tĂ©s, il permet la discussion par le biais de ses espĂšces minĂ©rales de nouveaux Ă©lĂ©ments quant Ă la genĂšse propre de ce genre de magma. Ainsi, lâanalyse des caractĂšres de la topaze conduit Ă dresser une classification typologique afin dâĂ©tudier les relations pouvant exister entre les formes, la composition chimique et les conditions de genĂšse (environnement chimique, tempĂ©rature, pressionâŠ) de ce minĂ©ral. Lâapplication de cette nouvelle mĂ©thode au cas particulier que reprĂ©sente la solution solide naturelle des topazes de Blond, confirme lâexistence de deux gĂ©nĂ©rations de topazes magmatiques (fluor-topazes hydroxylĂ©es et fluor-topazes). Par ailleurs, ces particularitĂ©s typologiques ne sont pas en faveur dâun contrĂŽle thermique mais on montre l'existence de liens pĂ©trogĂ©nĂ©tiques avec la fugacitĂ© initiale du magma en fluor. Lâeffet dĂ©gagĂ© de lâexamen des muscovites lithinifĂšres nĂ©cessite la prise en compte dâun Ă©tat dâĂ©quilibre entre ces diffĂ©rents minĂ©raux fluorĂ©s. En revanche, le comportement gĂ©ochimique original des ongonites endogranitiques de Blond, trouve son appui dans la dĂ©mixion dâune phase fluide riche en F, Li, W, T.R. lourdes et autres traces. Alors que les informations dont on dispose actuellement aboutissent Ă lâĂ©bauche dâune systĂ©matique intraongonitique, mise en relation avec divers faits expĂ©rimentaux. Sur le plan de pĂ©trologie structurale, les donnĂ©es acquises fournissent un exemple dâinterfĂ©rence entre gonflement diapirique et cisaillements rĂ©gionaux. La gĂ©omĂ©trie et la nature des structures rencontrĂ©es dans le massif signifieraient un mode syncinĂ©matique de mise en place par montĂ©e diapirique. Cet Ă©vĂ©nement nous parait indissociable dâun rĂ©gime de cisaillement dextre de la faille dOradour Sur Glane. Durant cette phase de dĂ©formation estimĂ©e stĂ©phanienne la persistance des contraintes majeures submĂ©ridiennes fait fonctionner un systĂšme de dĂ©crochements conjuguĂ©s ENE-WSW senestre entrainant lâindividualisation Ă lâĂ©tat visqueux dâune structuration verticale en panneaux de mĂȘme attitude et induit lâemplacement du magmatisme ongonitique, accompagnĂ© dâun chevelu de quartz Ă wolframite. Des Ă©vidences microstructurales de recristallisation syntectonique des micas ferrolithiques de Blond permettent dâĂ©tablir des systĂšmes de constituants adĂ©quats pour lâĂ©tude des traceurs gĂ©ochimiques des fabriques planaires superposĂ©es. Par une mĂ©thode proposĂ©e, dâindexation de lâorientation minĂ©rale on met en Ă©vidence que le chimisme des Li-Fe micas est liĂ© Ă leur microcontexte structural et souligne quatre directions superposĂ©es dâimportance rĂ©gionale, ainsi que leur succession. Les Ă©volutions de compositions se rapportent Ă la dĂ©stabilisation de lâandalousite ignĂ©e de Blond, et dâautre part Ă la redistribution tardive du Li et F qui sâintĂšgre dans lâorganisation en panneaux du massif. Les conditions de production de la paragenĂšse Ă andalousite indiquent une profondeur de lâordre de 12 Km. La mobilitĂ© verticale du magma anatectique contribue Ă ces modifications minĂ©ralogiques. Enfin, lâĂ©tude de la dĂ©formation plastique du quartz a servi de guide pour confirmer certaines donnĂ©es de lâimage Ă©laborĂ©e pour le massif de Blond
Etude des magmatismes leucogranitique et ongonitique du Blond (Haut-Limousin-Massif Central francais) : relations avec une mise en place syntectonique du massif granitique
SIGLECNRS T 63634 / INIST-CNRS - Institut de l'Information Scientifique et TechniqueFRFranc
Dynamique de la relation dipolaire à la transition vitreuse dans les matériaux polymÚres par réponses transitoires des courants de dépolarisation thermostimulés
L Ă©tude des phĂ©nomĂšnes de relaxation occupent une importante partie dans le domaine de recherche en polymĂšres. Plusieurs techniques d analyses sont utilisĂ©es pour rĂ©aliser ces Ă©tudes, parmi lesquelles figure la mĂ©thode des courants de dĂ©polarisation thermostimulĂ©s CDTS. Cette mĂ©thode est trĂšs sensible et ses donnĂ©es sont traditionnellement obtenues selon deux protocoles conduisant Ă des spectres bien connu complexe et spectres Ă©lĂ©mentaires. Les travaux de cette thĂšse se divisent en plusieurs parties distinctes mais complĂ©mentaires. Dans un premier temps, nous avons proposĂ© un nouveau protocole en CDTS reposant sur une modification de l algorithme expĂ©rimental. Ce protocole nous a permis de remplacer un seul point pour une tempĂ©rature donnĂ©e par une quantitĂ© importante de points exprimant une dynamique de relaxation. Pour mettre en place les diffĂ©rents paramĂštres de ce protocole, nous avons rĂ©alisĂ© un plan d expĂ©riences sur des Ă©chantillons de PET que nous avons pris comme rĂ©fĂ©rence. Nous avons ensuite mis en place une nouvelle analyse temporelle basĂ©e sur la mĂ©thode mathĂ©matique d optimisation du Simplex-DLTS et nos rĂ©sultats ont montrĂ©s que le modĂšle le plus convenant Ă©tait celui Ă deux temps de relaxation t1 et t2 (somme de deux exponentielles). Nous avons appliquĂ© cette nouvelle mĂ©thode pour l Ă©tude de diffĂ©rents polymĂšres : le PETg, le PLLA et le PC oĂč pour chacun de ses polymĂšres, la mĂ©thode a rĂ©vĂ©lĂ© l existence des deux temps de relaxation. Avec le Simplex-CDTS, nous avons mis en Ă©vidence le principe d hĂ©tĂ©rogĂ©nĂ©itĂ© dynamique des polymĂšres. Nous avons Ă©galement Ă©tudiĂ© par cette mĂ©thode, l effet du vieillissement ainsi que celui de la cristallisation. La mĂ©thode Simplex-CDTS s est avĂ©rĂ©e Ă©galement ĂȘtre une bonne technique de substitution pour l Ă©tude de la relaxation Ă la tempĂ©rature de transition vitreuse pouvant remplacer aisĂ©ment l utilisation et le croisement de donnĂ©es obtenues par application de trois techniques distinctes.The study of relaxation phenomena plays an important part in the field of polymer research. Several analysis techniques are used for these studies, among which is the Thermo stimulated depolarization current TSDC spectroscopy. This method is very sensitive and its data are typically obtained by two protocols leading to well-know spectra, complex spectra and elementary spectra. The work of this thesis is divided into several separate but complementary. Initially, we proposed a new protocol on TSDC based on a modification of the experimental algorithm. This protocol allowed us to replace a single point at a given temperature by a significant amount of points expressing the dynamics of relaxation. To establish the parameters of this protocol, we conducted a design experiments on PET samples that we took as a reference. Then, we set up a new timing analysis method based on mathematical optimization Simplex-DLTS and our results have shown that the most suitable model was the two-relaxation time t1 and t2 (sum of twot exponential). We applied this new method for the study of different polymers: PETG, PLLA and the PC where for each of its polymers, the method revealed the existence of two relaxation times. With the Simplex-CDTS, we have demonstrated the principle of dynamic heterogeneity of polymers. We also studied by this method, the effect of ageing and that of crystallization. Simplex-CDTS method also has to be a good alternative technique for the study of relaxation at the glass transition temperature and can easily replace the use and crossing of data obtained by applying three different techniques.ROUEN-BU Sciences Madrillet (765752101) / SudocSudocFranceF
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