Éditeur(s) : HAL CCSD Elsevier
Résumé : International audience
Gold mineralisation in the Yatela Main gold mine is hosted in a saprolitic residuum situated above Birimian supracrustal rocks, and at depth. The supracrustal rocks comprise metamorphosed calcitic and dolomitic marbles that were intruded by diorite (2106 ± 10 Ma, 207Pb/206Pb), and sandstone-siltstone-shale sequences (youngest detrital zircon population dated at 2139 ± 6 Ma). In-situ gold-sulphide mineralisation is associated with hydrothermal activity synchronous to emplacement of the diorite and forms a sub-economic resource; however, the overlying saprolitic residuum hosts economic gold mineralisation in friable lateritized palaeosols and aeolian sands (loess).Samples of saprolitic residuum were studied to investigate the morphology and composition of gold grains as a proxy for distance from source (and possible exploration vector) because the deposit hosts both angular and detrital gold suggesting both proximal and distal sources. U–Pb geochronology of detrital zircons also indicated a proximal and distal source, with the age spectra giving Archaean (2.83–3.28 Ga), and Palaeoproterozoic (1.95–2.20 Ga) to Neoproterozoic (1.1–1.8 Ga) zircons in the Yatela depocentre. The 1.1–1.8 Ga age spectrum restricts the maximum age for the first deposition of the sedimentary units in the Neoproterozoic, or during early deposition in the Taoudeni Basin. Models for formation of the residuum include distal and proximal sources for detritus into the depocentre, however, it is more likely that material was sourced locally and included recycled material. The creation of a deep laterite weathering profile and supergene enrichment of the residuum probably took place during the mid-Cretaceous-early Tertiary.
ISSN: 0899-5362

hal-01277679
https://hal.archives-ouvertes.fr/hal-01277679
DOI : 10.1016/j.jafrearsci.2015.07.017

Éditeur(s) : ISTPM
Résumé : The study of the foraminifers contained in the samples collected by the "President-Theodore-Tissier" during its 1948 cruise enabled:1° to draw up the list of the genera and species dwelling in the north-eastern Atlantic Ocean;2° to notice that some of these species are widely distributed but that others are localized in these areas. Among them are:Quinqueloculina angulataQuinqueloculina dunkerquianaQuinqueloculina lataQuinqueloculina quadrangularisGaudryina rudisNonionella turgidaBolivina pseudo-plicataBolivina laevigataDiscorbis globularis var. anglicaDiscorbis millettiiDiscorbis nitida3° to clarify a few taxonomic points for some species;4° to classify the different stations according to the nature of the sea bed and to determine the foriminifer fauna living in each category;5° to establish the important role played by the substratum, not only because of its nature, but also because of the biocenose it is linked to.
L'étude des Foraminifères contenus dans les échantillons récoltes par le « President-Theodore-Tissier » au cours de sa campagne de 1948 a permis: 1° - d'établir la liste des genres et espèces vivant dans cette partie nord-orientale de l'Océan Atlantique; 2° de constater que certaines de ces formes ont une large distribution géographique mais que d'autres sont localisées dans ces régions. Parmi ces dernières on peut citer: Quinqueloculina angulata Quinqueloculina dunkerquiana Quinqueloculina lata Quinqueloculina quadrangularis Gaudryina rudis Nonionella turgida Bolivina pseudo-plicata Bolivina laevigata Discorbis globularis var. anglica Discorbis millettii Discorbis nitida 3° de préciser pour certaines espèces quelques points d'ordre systématique; 4° de classer les différentes stations suivant la nature du fond et de déterminer la composition de la faune des Foraminifères qui pullulent dans chacune des catégories; 5° de constater le rôle important joue par le substratum, non seulement par sa nature, mais aussi par la biocénose qui lui est étroitement liée. ATTENTION : Ce texte a été extrait du document par un processus automatique, non contrôlé, de reconnaissance optique de caractères (OCR). Il est donc susceptible de comporter des erreurs. En cas de doute, consultez le fichier PDF.
Revue des Travaux de l'Institut des Pêches Maritimes (0035-2276) (ISTPM), 1958-06 , Vol. 22 , N. 2 , P. 148-211

Droits : Ifremer
http://archimer.ifremer.fr/doc/1958/publication-4597.pdf
http://archimer.ifremer.fr/doc/00000/4597/

Éditeur(s) : Elsevier
Résumé : To elucidate the origin of the silicic acid (DSi) anomaly observed along the 4000 isobath on the Congo margin, we have established a benthic Si mass balance and performed direct measurements of biogenic silica (bSiO(2)) dissolution in the deep waters and in the sediments. Results strongly suggest that the anomaly originates from the sediments; the intensity of DSi recycling is consistent with the degradation of organic matter, as observed from Si:O-2 ratios in the benthic fluxes compared to that ratio observed in the anomalies. Strong imbalances, observed in both the Si and C mass balances, suggest that the biogenic matter that degrades and dissolves in these sediments near 4000 m does not come from pelagic sedimentation. It is probably not coming also from the deep channel, because observations were similar in the deep channel vicinity (site D) and further south, far from its influence (site C). The composition of the sediments, with an Si:C ratio close to that observed on continental shelves, suggests that this matter is coming from downslope transport. A first estimate of the magnitude of this flux at global scale, close to 12 T mol Si yr(-1), suggests that it may be an important path for transferring Si from land to ocean.
Deep Sea Research Part II: Topical Studies in Oceanography (0967-0645) (Elsevier), 2009-11 , Vol. 56 , N. 23 , P. 2197-2207

Droits : 2009 Elsevier Ltd All rights reserved.
http://archimer.ifremer.fr/doc/2009/publication-7410.pdf
DOI:10.1016/j.dsr2.2009.04.003
http://archimer.ifremer.fr/doc/00000/7410/

Éditeur(s) : HAL CCSD Elsevier
Résumé : International audience
Background : Biological communities are normally composed of a few abundant and many rare species. This pattern is particularly prominent in microbial communities, in which most constituent taxa are usually extremely rare. Although abundant and rare subcommunities may present intrinsic characteristics that could be crucial for understanding community dynamics and ecosystem functioning, microbiologists normally do not differentiate between them. Here, we investigate abundant and rare subcommunities of marine microbial eukaryotes, a crucial group of organisms that remains among the least-explored biodiversity components of the biosphere. We surveyed surface waters of six separate coastal locations in Europe, independently considering the picoplankton, nanoplankton, and microplankton/mesoplankton organismal size fractions.Results : Deep Illumina sequencing of the 18S rRNA indicated that the abundant regional community was mostly structured by organismal size fraction, whereas the rare regional community was mainly structured by geographic origin. However, some abundant and rare taxa presented similar biogeography, pointing to spatiotemporal structure in the rare microeukaryote biosphere. Abundant and rare subcommunities presented regular proportions across samples, indicating similar species-abundance distributions despite taxonomic compositional variation. Several taxa were abundant in one location and rare in other locations, suggesting large oscillations in abundance. The substantial amount of metabolically active lineages found in the rare biosphere suggests that this subcommunity constitutes a diversity reservoir that can respond rapidly to environmental change.Conclusions : We propose that marine planktonic microeukaryote assemblages incorporate dynamic and metabolically active abundant and rare subcommunities, with contrasting structuring patterns but fairly regular proportions, across space and time.
ISSN: 0960-9822

hal-01149637
http://hal.upmc.fr/hal-01149637
http://hal.upmc.fr/hal-01149637/document
http://hal.upmc.fr/hal-01149637/file/Logares_et_al_CurrentBiol_accepted.pdf
DOI : 10.1016/j.cub.2014.02.050

Éditeur(s) : HAL CCSD Nature Publishing Group
Résumé : International audience
Everyone is subject to environmental exposures from various sources, with negative health impacts (air, water and soil contamination, noise, etc.or with positive effects (e.g. green space). Studies considering such complex environmental settings in a global manner are rare. We propose to use statistical factor and cluster analyses to create a composite exposure index with a data-driven approach, in view to assess the environmental burden experienced by populations. We illustrate this approach in a large French metropolitan area. The study was carried out in the Great Lyon area (France, 1.2 M inhabitants) at the census Block Group (BG) scale. We used as environmental indicators ambient air NO2 annual concentrations, noise levels and proximity to green spaces, to industrial plants, to polluted sites and to road traffic. They were synthesized using Multiple Factor Analysis (MFA), a data-driven technique without a priori modeling, followed by a Hierarchical Clustering to create BG classes. The first components of the MFA explained, respectively, 30, 14, 11 and 9% of the total variance. Clustering in five classes group: (1) a particular type of large BGs without population; (2) BGs of green residential areas, with less negative exposures than average; (3) BGs of residential areas near midtown; (4) BGs close to industries; and (5) midtown urban BGs, with higher negative exposures than average and less green spaces. Other numbers of classes were tested in order to assess a variety of clustering. We present an approach using statistical factor and cluster analyses techniques, which seem overlooked to assess cumulative exposure in complex environmental settings. Although it cannot be applied directly for risk or health effect assessment, the resulting index can help to identify hot spots of cumulative exposure, to prioritize urban policies or to compare the environmental burden across study areas in an epidemiological framework.Journal of Exposure Science and Environmental Epidemiology advance online publication, 24 September 2014; doi:10.1038/jes.2014.66.
ISSN: 1559-0631

hal-01069587
https://hal.archives-ouvertes.fr/hal-01069587
https://hal.archives-ouvertes.fr/hal-01069587/document
https://hal.archives-ouvertes.fr/hal-01069587/file/Article_multiexpo_20140708_c.pdf
DOI : 10.1038/jes.2014.66

Éditeur(s) : HAL CCSD Public Library of Science
Résumé : International audience
Forest successional processes following disturbance take decades to play out, even in tropical forests. Nonetheless, records of vegetation change in this ecosystem are scarce, increasing the importance of the chronosequence approach to study forest recovery. However, this approach requires accurate dating of secondary forests, which until now was a difficult and/or expensive task. Cecropia is a widespread and abundant pioneer tree genus of the Neotropics. Here we propose and validate a rapid and straightforward method to estimate the age of secondary forest patches based on morphological observations of Cecropia trees. We found that Cecropia-inferred ages were highly correlated with known ages of the forest. We also demonstrate that Cecropia can be used to accurately date disturbances and propose twenty-one species distributed all over the geographical range of the genus as potential secondary forest chronometer species. Our method is limited in applicability by the maximal longevity of Cecropia individuals. Although the oldest chronosequence used in this study was 20 years old, we argue that at least for the first four decades after disturbance, the method described in this study provides very accurate estimations of secondary forest ages. The age of pioneer trees provides not only information needed to calculate the recovery of carbon stocks that would help to improve forest management, but also provides information needed to characterize the initial floristic composition and the rates of species remigration into secondary forest. Our contribution shows how successional studies can be reliably and inexpensively extended without the need to obtain forest ages based on expensive or potentially inaccurate data across the Neotropics.
ISSN: 1932-6203

halsde-00757518
https://hal.archives-ouvertes.fr/halsde-00757518
DOI : 10.1371/journal.pone.0042643
PUBMED : 22916144

Éditeur(s) : HAL CCSD Ecole nationale du génie rural
Résumé :  
A l'échelle de l'arbre, la fertilité chimique des sols semble expliquer la localisation majoritairement superficielle du système racinaire, alors que le type de drainage explique la forte variabilité de sa répartition verticale. Les racines profondes, malgré leur faible proportion, jouent un rôle important pour extraire l'eau en saison sèche. A l'échelle du peuplement, les variations latérales du sol influent sur des processus tels que la compétition inter-individuelle et la sylvigénèse. Pour les sols de terre ferme, plus les conditions édaphiques sont contraignantes, plus les gros arbres sont rares dans le peuplement forestier. Celui-ci est dense lorsque le sol est très aminci, moins dense en situation hydromorphe. Le sol influence nettement la composition floristique des peuplements. Mais d'autres facteurs tels la dynamique sylvigénétique ou la dynamique propre à chaque population ont un poids très important. Des résultats divergents conduisent à formuler de nouvelles hypothèses, parmi celles-ci l'influence majeure de l'épaisseur du profil d'altération.
ISSN: 0035-2829

hal-01031882
https://hal.archives-ouvertes.fr/hal-01031882

Éditeur(s) : HAL CCSD
Résumé : International audience
MOTIVATION: Imaging mass spectrometry (IMS) is a maturating technique of molecular imaging. Confidence in the reproducible quality of IMS data is essential for its integration into routine use. However, the predominant method for assessing quality is visual examination, a time consuming, unstandardized and non-scalable approach. So far, the problem of assessing the quality has only been marginally addressed and existing measures do not account for the spatial information of IMS data. Importantly, no approach exists for unbiased evaluation of potential quality measures. RESULTS: We propose a novel approach for evaluating potential measures by creating a gold-standard set using collective expert judgements upon which we evaluated image-based measures. To produce a gold standard, we engaged 80 IMS experts, each to rate the relative quality between 52 pairs of ion images from MALDI-TOF IMS datasets of rat brain coronal sections. Experts' optional feedback on their expertise, the task and the survey showed that (i) they had diverse backgrounds and sufficient expertise, (ii) the task was properly understood, and (iii) the survey was comprehensible. A moderate inter-rater agreement was achieved with Krippendorff's alpha of 0.5. A gold-standard set of 634 pairs of images with accompanying ratings was constructed and showed a high agreement of 0.85. Eight families of potential measures with a range of parameters and statistical descriptors, giving 143 in total, were evaluated. Both signal-to-noise and spatial chaos-based measures performed highly with a correlation of 0.7 to 0.9 with the gold standard ratings. Moreover, we showed that a composite measure with the linear coefficients (trained on the gold standard with regularized least squares optimization and lasso) showed a strong linear correlation of 0.94 and an accuracy of 0.98 in predicting which image in a pair was of higher quality. AVAILABILITY AND IMPLEMENTATION: The anonymized data collected from the survey and the Matlab source code for data processing can be found at: https://github.com/alexandrovteam/IMS_quality. CONTACT: theodore.alexandrov@embl.de
Bioinformatics (Oxford, England)

hal-01163754
https://hal-univ-rennes1.archives-ouvertes.fr/hal-01163754
DOI : 10.1093/bioinformatics/btv266
PUBMED : 26072506

Éditeur(s) : HAL CCSD
Résumé :  
The main aspects of wood mechanics are approached through the role played by wood as the building material of the tree. The main concepts used by nature: progressive setting up of tree weight and architecture, multifunctional role of wood and adaptability to hazard and long-term evolution, are clarified together with their consequence on the multilayered, anisotropic nature of wood. The technological choices of the plant world as the cellular structure, the use of composite with oriented fibres and hydro-carbonated polymers, as well as the systematic prestressing of every new layer, bear obvious consequences on the type of mechanical behaviour of wood. The local control of the level of prestressing through minor modifications of the cell-wall biosynthesis allows the tree to adapt to conditions of light exploration that will evolve according to time and risk occurrence. This analysis of wood genesis process permits in return to improve our understanding of the mechanical behaviour of the material in relation with the parameters of the microstructure.
Comptes Rendus de l'Académie des Sciences Série 2

hal-01032151
https://hal.archives-ouvertes.fr/hal-01032151
DOI : 10.1016/S1620-7742(01)01380-0

Éditeur(s) : HAL CCSD Springer Verlag
Résumé : International audience
We show that the lower limit of a sequence of maximal monotone operators on a reflexive Banach space is a representable monotone operator. As a consequence, we obtain that the variational sum of maximal monotone operators and the variational composition of a maximal monotone operator with a linear continuous operator are both representable monotone operators.
ISSN: 0927-6947

hal-00698802
https://hal.archives-ouvertes.fr/hal-00698802

Éditeur(s) : Wiley-blackwell
Résumé : An ecomorphological method was developed, with a focus on predation functions, to define functional groups in the Celtic Sea fish community. Eleven functional traits, measured for 930 individuals from 33 species, led to 11 functional groups. Membership of functional groups was linked to body size and taxonomy. For seven species, there were ontogenetic changes in group membership. When diet composition, expressed as the proportions of different prey types recorded in stomachs, was compared among functional groups, morphology-based predictions accounted for 28-56% of the interindividual variance in prey type. This was larger than the 12-24% of variance that could be explained solely on the basis of body size. (C) 2013 The Fisheries Society of the British Isles
Journal Of Fish Biology (0022-1112) (Wiley-blackwell), 2013-08 , Vol. 83 , N. 2 , P. 355-377

Droits : 2013 The Fisheries Society of the British Isles
http://archimer.ifremer.fr/doc/00152/26294/24831.pdf
DOI:10.1111/jfb.12177
http://archimer.ifremer.fr/doc/00152/26294/

Éditeur(s) : HAL CCSD Elsevier
Résumé : International audience
Serpentinites from subduction environments represent an important sink for fluid-mobile elements. In order to constrain geochemical behavior of fluid-mobile elements hosted by serpentine phases during subduction processes, we carried out a geochemical study (trace elements and Pb isotopes) of a series of serpentinites and cumulates from the accretionary wedge of Greater Caribbean (Cuba and Dominican Republic). The trace element compositions of the primary and alteration-related phases were analyzed in situ using LA-HR-ICP-MS techniques. The studied samples represent parts of the subducted proto-Atlantic oceanic lithosphere, which has experienced low to high grade metamorphism (greenschist to eclogite facies), before being exhumed; a subset of these samples were derived from the mantle wedge. This sampling provides the opportunity to trace the chemical mobility of fluid-mobile elements during prograde metamorphism along a cold geotherm in an oceanic subduction setting.
ISSN: 0009-2541

hal-00720895
https://hal.archives-ouvertes.fr/hal-00720895
DOI : 10.1016/j.chemgeo.2012.04.009

Éditeur(s) : HAL CCSD Springer Verlag
Résumé : International audience
The structure and dynamic evolution of a mountain belt piedmont are controlled by strong interactions between tectonics, surface processes (erosion, sedimentation), and climate. Studying these couplings relies on detailed geometric and kinematic analysis of morphostructural markers (folds, faults, terraces, alluvial surfaces) and analysis of syntectonic sedimentation. To study quantitatively how these markers form, evolve and record deformation, we developed a new analogue modelling approach using a specific composite granular material. The originality stands in the simultaneous modelling of orogenic deformation mechanisms and erosion-transport-sedimentation processes, but also in the use of techniques allowing quantitative measurement of morphostructural evolution. This methodology opens new perspectives in the fields of geomorphology (relief dynamics), seismotectonics (study of active faults), and sedimentology (including sequential stratigraphy).
ISSN: 0010-7999

hal-00411972
https://hal.archives-ouvertes.fr/hal-00411972
DOI : 10.1016/j.crte.2008.01.005

Éditeur(s) : HAL CCSD Seoul National University
Résumé : http://www.episodes.org/backissues/302/abstract2.htm
International audience
The Trans-North China Belt (TNCB) is a Paleoproterozoic collisional orogen (ca. 1.9-1.8 Ga) responsible for the amalgamation of the North China Craton. Detail field works in Lüliangshan, Hengshan, Wutaishan and Fuping massifs where the belt is well exposed, allow us to draw new tectonic map and crustal-scale cross sections. The available petrologic, radiometric, geochronologic data are integrated in a geodynamic evolution scheme for this orogen. The Low Grade Mafic Unit (LGMU) is interpreted as an ophiolitic nappe rooted in a suture zone located in the western part of the Lüliangshan. This ophiolitic nappe overthrusts to the SE upon the Orthogneiss-Volcanites Unit (OVU) that consists of a bimodal volcanicsedimentary series metamorphosed under amphibolite facies conditions intruded by calcalkaline orthogneiss. The OVU is a composite Neoarchean-Paleoproterozoic magmatic arc developed during two stages (ca. 2500 and 2100 Ma) upon a continental basement corresponding to the western extension of the Neoarchean Fuping massif. The OVU overthrusts to the SE the Fuping massif along the Longquanguan shear zone. This stack of nappe, coeval with an amphibolite facies metamorphism, is dated at ca 1880 Ma. Subsequently, the metamorphic series experienced a widespread migmatization at 1850 Ma and was intruded by post-orogenic plutons dated at 1800 Ma. The weakly to unmetamorphosed Hutuo Supergroup unconformably overlies the metamorphosed and ductilely deformed units (OVU and LGMU), but it is also involved in a second tectonic phase developed in subsurface conditions. These structural features lead us to question the ca 2090 Ma age attributed to the Hutuo supergroup. Moreover, in the Fuping massif, several structural and magmatic lines of evidence argue for an earlier orogenic event at ca 2100 Ma that we relate to an older west-directed subduction below the Fuping Block. The Taihangshan Fault might be the location of a possible suture zone between the Fuping Block and an eastern one. A geodynamic model, at variance with previous ones, is proposed to account for the formation of the TNCB. In this scheme, three Archean continents, namely from West to East, the Ordos, Fuping and Eastern Blocks are separated by the Lüliang and Taihang Oceans. The closure of the Taihang Ocean at ca 2100 Ma by westward subduction below the Fuping Block accounts for the arc magmatism and the 2100 Ma orogeny. The second collision at 1900-1880 Ma between the Fuping and Ordos blocks is responsible for the main structural, metamorphic and magmatic features of the Trans-North China Belt.
ISSN: 0705-3797

insu-00152972
https://hal-insu.archives-ouvertes.fr/insu-00152972
https://hal-insu.archives-ouvertes.fr/insu-00152972/document
https://hal-insu.archives-ouvertes.fr/insu-00152972/file/Episodes_TNCB_Faure_et_al.pdf

Éditeur(s) : HAL CCSD Springer Verlag
Résumé : International audience
Ecosystems are commonly affected by natural, episodic disturbances that can abruptly and drastically alter communities. Although it has been shown that resilient ecosystems can eventually recover to pre-disturbed states, the extent to which communities in early stages of recovery could be affected by multiple anthropogenic stressors is poorly understood. Pervasive and rising anthropogenic stressors in coastal marine systems that could interactively affect the recovery of these systems following natural disturbances include high sedimentation, nutrient enrichment, and overfishing. Using a 6-month field experiment, we examined the effects of all combinations of these three stressors on key functional groups in the benthic community growing on simulated, post-disturbance reef patches within a system recovering from large-scale natural disturbances (corallivorous seastar outbreak and cyclone). Our study revealed that sedimentation, nutrient enrichment, and overfishing (simulated using exclusion cages) interactively affected coral survival and algal growth, with taxon-specific effects at multiple scales. First, our treatments affected corals and algae differently, with sedimentation being more detrimental to macroalgal growth but less detrimental to coral (Porites rus) survival in caged plots, driving significant interactions between sedimentation and caging for both taxa. We also observed distinct responses between coral species and between algal functional groups, with the most extensive responses from algal turf biomass, for which sedimentation suppressed the synergistic (positive) combined effect of nutrient enrichment and caging. Our findings suggest that different combinations of ubiquitous anthropogenic stressors, related to either sea- or land-based activities, interactively influence community recovery from disturbance and may alter species compositions in the resulting community. Our findings further suggest that anthropogenic stressors could promote further degradation of coral reefs following natural disturbances by inhibiting recovery to coral-dominated states that provide vital ecosystem services to coastal populations worldwide.
ISSN: 0722-4028

hal-01430977
https://hal-univ-perp.archives-ouvertes.fr/hal-01430977
DOI : 10.1007/s00338-016-1489-x

Éditeur(s) : HAL CCSD Springer Verlag
Résumé : International audience
Disentangling the autotrophic and heterotrophic components of soil CO2 efflux is critical to understanding the role of soil system in terrestrial carbon (C) cycling. In this study, we combined a stable C-isotope natural abundance approach with the trenched plot method to determine if root exclusion significantly affected the isotopic composition (δ13C) of soil CO2 efflux (RS). This study was performed in different forest ecosystems: a tropical rainforest and two temperate broadleaved forests, where trenched plots had previously been installed. At each site, RS and its δ13C (δ13CRs) tended to be lower in trenched plots than in control plots. Contrary to RS, δ13CRs differences were not significant. This observation is consistent with the small differences in δ13C measured on organic matter from root, litter and soil. The lack of an effect on δ13CRs by root exclusion could be from the small difference in δ13C between autotrophic and heterotrophic soil respirations, but further investigations are needed because of potential artefacts associated with the root exclusion technique.
ISSN: 0032-079X

bioemco-00353850
https://hal-bioemco.ccsd.cnrs.fr/bioemco-00353850
DOI : 10.1007/s11104-008-9844-5

Éditeur(s) : HAL CCSD Elsevier
Résumé : International audience
This paper is concerned with weighted pseudo almost automorphic functions, which are more general and complicated than weighted pseudo almost periodic functions. Using these properties, we establish an existence and uniqueness theorem for pseudo almost automorphic mild solutions to semilinear differential equations in a Banach spaces which extends known results.
ISSN: 0362-546X

hal-00617634
https://hal.archives-ouvertes.fr/hal-00617634

Éditeur(s) : HAL CCSD
Résumé : Session "Posters"
National audience
Nous présentons une méthode permettant la mesure complète de la pose de la tête lors de captures vidéo monoculaires. Ce procédé utilise un modèle de visage et de texture précis. Le modèle facial, construit à partir d'une distribution de scans 3D haute résolution de visages, permet de générer des densités adaptées aux résolutions effectives. L'étape d'initialisation de la position du modèle est cruciale car elle conditionne le suivi ultérieur de la pose. Nous proposons ainsi d'utiliser une métrique composite construite sur des textures extraites de trois bases de données différentes. L'algorithme est alors capable de suivre le visage dans de vastes plages de poses avec une grande précision. Nous proposons des séquences vidéo de test dotées de vérité-terrain de pose précise et indépendante (précision de 0.1 degrés RMS)
Actes de la conférence RFIA 2012
Lyon, France

hal-00656565
https://hal.archives-ouvertes.fr/hal-00656565
https://hal.archives-ouvertes.fr/hal-00656565/document
https://hal.archives-ouvertes.fr/hal-00656565/file/rfia2012_submission_118.pdf

Éditeur(s) : Blackwell science
Résumé : Peneid shrimp are commonly reared in clear-water aquaria or tanks for short-term studies of 4-6 weeks during controlled experiments, such as nutrition studies to estimate dietary nutrient requirements. Recently, in line with the genetic program at Centre Oceanologique du Pacifique (COP), experimental clear-water facilities were tested for the first time over a longer rearing period. Environmental conditions used to maintain animal growth in clear-water system using a well-balanced diet were defined. After 100 days, shrimp growth rates tended to decrease and only by adjusting the diet could shrimp complete their life cycle and reach maturation size of around 40 g. This paper presents information on stocking density, diet quality and husbandry linked to reproduction that must be considered to successfully rear animals from PL's to breeder size in clear water. By following these protocols a minimum amount of breeders can be used to meet production goals. Moreover, by isolating a small group of individuals, genetic diversity can be preserved, thereby allowing specific crosses for selective breeding purposes. Length of trials, amount of feed, composition of feed, growth performances and maturation success are reported and should encourage further studies to optimize rearing conditions in clear-water rearing.
Aquaculture Research (1355-557X) (Blackwell science), 2004-11 , Vol. 35 , N. 13 , P. 1244-1252

Droits : 2004 Blackwell Synergy
http://archimer.ifremer.fr/doc/2004/publication-619.pdf
DOI:10.1111/j.1365-2109.2004.01145.x
http://archimer.ifremer.fr/doc/00000/619/

Éditeur(s) : HAL CCSD
Résumé : International audience
Traffic air pollution is a major health problem and is recognized as an important risk factor for cardiovascular disease. Even so the role of particles-induced adverse health effects is well established, recent studies outlined the contribution of nitrogen dioxide (NO2) in these effects, in particular on the cardiovascular function. The main sources of this pollutant are oxidation catalysts used to reduce emissions of carbon monoxide and non-methane hydrocarbons from the exhaust of diesel engines and also to facilitate filter regeneration. However, the contribution of NO2 compared to other gaseous and particulate pollutants remains unknown. Consequently, the main objective of this study was to analyze the specific contributions of NO2 in the traffic-related air pollution-induced cardiovascular adverse effects. For this, Wistar rats were exposed for 3 weeks (3h/day, 5 days/week) to either a continuous flow of catalyzed diesel exhaust (DE), particle free or whole DE (particles concentration 2mg/m3), either to a continuous flow of NO2 used at a concentration identical to that measured in the exhaust line. The composition of the emission and the NO2 analyses were monitored on-line during the whole experiment. We evaluated cardiac function and biological effects after 16h recovery in clean air. DE or NO2 exposures induced a modest cardiac dysfunction characterized by an increase in left ventricular diameters and a decrease in fractional shortening. In the case of DE, the presence of particles did not worsen the impairment of cardiac function. In parallel to this effect, mitochondrial function was altered as illustrated by the reduction of the oxygen consumption and of the ATP production. Mitochondrial reactive oxygen species was increased only by the NO2 exposure. In conclusion, these results suggest that DE-induced cardiac dysfunction is due to, at least in part, to NO2 present in DE.
Archives of Cardiovascular Diseases Supplements
Toulouse, France

hal-01150495
https://hal-univ-rennes1.archives-ouvertes.fr/hal-01150495
DOI : 10.1016/S1878-6480(15)30036-7