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Réhabilitation des sols pollués par les éléments traces métalliques grâce aux bactéries du sol associées à la rhizosphère de Miscanthus x giganteus / Revitalisation of soils polluted by heavy metals by soil bacteria associated to Miscanthus x giganteus rhizosphereMartinez Chois, Claudia 06 November 2012 (has links)
Le sol est une ressource non renouvelable à conserver en raison de son importance socio-économique et environnementale. Mais, les activités (bio)industrielles peuvent le dégrader et entraîner l'apparition de friches à pollutions persistantes. La capacité de Miscanthus x giganteus à s'adapter aux sols de friches pollués en éléments traces métalliques (ETM), tout en favorisant la consolidation des processus de bioremédiation des polluants, sans entraîner d'impact négatif sur l'environnement, est étudiée. Des terrains lorrains, très impactés par l'activité industrielle passée, sont utilisés. Considérant la complexité des relations sol-plante-microorganismes, différents outils d'évaluation complémentaires (i.e. in vitro, en mésocosme et sur le terrain) sont employés afin de déterminer la réponse de chaque composante et de leurs interactions et ainsi déduire la durabilité de la méthode. La culture de M. x giganteus a un potentiel pour la réhabilitation des sols de friche à pollutions multimétalliques ou mixtes (+HAP), avec un double bénéfice : la phytostabilisation des ETM au niveau racinaire et la production d'une biomasse aérienne revalorisable (transfert limité des ETM). La plante n'altère pas les caractéristiques du sol qui participent à la mobilité des ETM (pH, CEC) ; les variations de celles liées à la fertilité du sol, de la toxicité (fraction liquide) et de l'accumulation des ETM par d'autres organismes, attestent de l'interaction avec le milieu qui rendrait les éléments plus disponibles. L'activité végétale est à l'origine des associations avec les bactéries du sol, où les phylotypes potentiellement métallorésistants (Zn, Cr) semblent communs aux sols utilisés / Soil is a nonrenewable resource to maintain because of its socio-economic and environmental importance. However, (bio)industrial activities can degrade soil and cause the appearance of persistent pollution brownfields. The ability of Miscanthus x giganteus to adapt to brownfield soils polluted with heavy metals (HM), while promoting the consolidation process of bioremediation of polluants, without causing a negative impact on the environment, is studied. Soils from Lorraine region (France), very affected by past industrial activity, are used. Considering the complexity of soil-plant-microorganisms relationships, various complementary assessment tools (i.e. in vitro,mesocosm and field) are used to determine the response of each component and their interactions, and thus deduce the sustainability of the method. The culture of M. x giganteus has great potential for rehabilitation of brownfield soils having a multimetallic pollution or mixed (+PAH) with a double benefit: phytostabilisation of HM at the root level and the production of biomass reclaimable (limited transfer of HM). The plant does not alter the characteristics of the soil involved in the mobility of HM (pH, CEC) ; but changes from those related to soil fertility, toxicity (liquid fraction) and the accumulation of HM by other organisms attest to the interaction of the plant with the elements that would make them more available. Plant's activity is causing associations with soil bacteria, for which the phylopes potentially métalloresistants (Zn, Cr) seem common in soils used
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ParTraP : un langage pour la spécification et vérification à l'exécution de propriétés paramétriques / ParTraP : A Language for the Specification and Runtime Verification of Parametric PropertiesBlein, Yoann 15 April 2019 (has links)
La vérification à l'exécution est une technique prometteuse pour améliorer la sûreté des systèmes complexes. Ces systèmes peuvent être instrumentés afin qu'ils produisent des traces d'exécution permettant d'observer leur utilisation dans des conditions réelles. Un défi important est de fournir aux ingénieurs logiciel un langage formel simple adapté à l'expression des exigences les plus importantes. Dans cette thèse, nous nous intéressons à la vérification de dispositifs médicaux. Nous avons effectué l'analyse approfondie d'un dispositif médical utilisé mondialement afin d'identifier les exigences les plus importantes, ainsi que la nature précise des traces d'exécution qu'il produit. À partir de cette analyse, nous proposons ParTraP, un langage défini formellement et dédié à la spécification de propriétés sur des traces finies. Il a été conçu pour être accessible à des ingénieurs logiciels non qualifiés en méthodes formelles grâce à sa simplicité et son style déclaratif. Le langage étend les patrons de spécification initialement proposé par Dwyer et. al. avec des opérateurs paramétriques et temps-réel, des portées emboîtable, et des quantificateurs de premier ordre. Nous proposons également une technique de mesure de couverture pour ParTraP, et que le niveau de couverture d'une propriété temporelle permet de mieux la comprendre, ainsi que le jeu de traces sur lequel elle est évaluée. Finalement, nous décrivons l'implémentation d'un environnement de développement intégré pour ParTraP, qui est disponible sous une licence libre. / Runtime verification is a promising technique to improve the safety of complex systems. These systems can be instrumented to produce execution traces enabling us to observe their usage in the field. A significant challenge is to provide software engineers with a simple formal language adapted to the expression of their most important requirements. In this thesis, we focus on the verification of medical devices. We performed a thorough analysis of a worldwide-used medical device in order to identify those requirements, as well as the precise nature of its execution traces. In the light of this study, we propose ParTraP, a formally defined language dedicated to property specification for finite traces. It is designed to be accessible to software engineers with no training in formal methods thanks to its simplicity and declarative style. The language extends the specification patterns originally proposed by Dwyer et al. with parametrized constructs, nested scopes, real-time and first-order quantification. We also propose a coverage measurement technique for ParTraP, and we show that coverage information provides insights on a corpus of traces as well as a deeper understanding of temporal properties. Finally, we describe the implementation of an Integrated Development Environment for ParTraP, which is available under a free and open-source license.
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Stratification de Newton des variétés de Shimura et formule des traces d’Arthur-Selberg / The Newton stratification of Shimura varieties and the Arthur-Selberg trace formulaKret, Arno 10 December 2012 (has links)
Nous étudions la stratification de Newton des variétés de Shimura de type PEL aux places de bonne réduction. Nous considérons la strate basique de certaines variétés de Shimura simples de type PEL modulo une place de bonne réduction. Sous des hypothèses simplificatrices nous prouvons une relation entre la cohomologie l-adique de ce strate basique et la cohomologie de la variété de Shimura complexe. En particulier, nous obtenons des formules explicites pour le nombre de points dans la strate basique sur des corps finis, en termes de représentations automorphes. Nous obtenons les résultats à l'aide de la formule des traces et de la troncature de la formule de Kottwitz pour le nombre de points sur une variété de Shimura sur un corps fini. Nous montrons, en utilisant la formule des traces, que n'importe quelle strate de Newton d'une variété de Shimura de type PEL de type (A) est non vide en une place de bonne réduction. Ce résultat a déjà été établi par Viehmann-Wedhorn; nous donnons une nouvelle preuve de ce théorème. Considérons la strate basique des variétés de Shimura associées à certains groupes unitaires dans les cas où cette strate est une variété finie. Alors, nous démontrons un résultat d' équidistribution pour les opérateurs de Hecke agissant sur cette strate. Nous relions le taux de convergence avec celui de la conjecture de Ramanujan. Dans nos formules ne figurent que des représentations automorphes cuspidales sur Gl_n pour lesquelles cette conjecture est connue, et nous obtenons donc des estimations très bonnes sur la vitesse de convergence. En collaboration avec Erez Lapid nous calculons le module de Jacquet d'une représentation en échelle pour tout sous-groupe parabolique standard du groupe général linéaire sur un corps local non-archimédien. / We study the Newton stratification of Shimura varieties of PEL type, at the places of good reduction. We consider the basic stratum of certain simple Shimura varieties of PEL type at a place of good reduction. Under simplifying hypotheses we prove a relation between the l-adic cohomology of this basic stratum and the cohomology of the complex Shimura variety. In particular we obtain explicit formulas for the number of points in the basic stratum over finite fields, in terms of automorphic representations. We obtain our results using the trace formula and truncation of the formula of Kottwitz for the number of points on a Shimura variety over a finite field. We prove, using the trace formula that any Newton stratum of a Shimura variety of PEL-type of type (A) is non-empty at a prime of good reduction. This result is already established by Viehmann-Wedhorn; we give a new proof of this theorem. We consider the basic stratum of Shimura varieties associated to certain unitary groups in cases where this stratum is a finite variety. Then, we prove an equidistribution result for Hecke operators acting on the basic stratum. We relate the rate of convergence to the bounds from the Ramanujan conjecture of certain particular cuspidal automorphic representations on Gl_n. The Ramanujan conjecture turns out to be known for these automorphic representations, and therefore we obtain very sharp estimates on the rate of convergence. We prove that any connected reductive group G over a non-Archimedean local field has a cuspidal representation. Together with Erez Lapid we compute the Jacquet module of a Ladder representation at any standard parabolic subgroup of the general linear group over a non-Archimedean local field.
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Estresse de metais na produtividade de compostos oriundos do metabolismo secund?rio de martianthus leucocephalus (mart. Ex benth.) J.f.b. PastoreJesus, Daniel da Silva de 29 April 2016 (has links)
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Previous issue date: 2016-04-29 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / Lamiaceae species have been widely studied due to their antioxidant, antimicrobial and antiviral properties. There is scientific interest in developing technologies for the enhancement of production systems of medicinal plants, given that the low concentration of bioactive compounds is a major obstacle to their economic exploitation. Works with some species have shown that traces metals such as Cd, Cu and Zn, act as abiotic elicitors, directly influencing in the production of bioactive substances. Martianthus leucocephalus (Mart. Ex Benth.) J.F.B. Pastore produces rich essential oil in isobornyl formate with high antimicrobial activity. This work aimed to evaluate the effect of Cd, Cu and Zn stress, on the species through growth, minerals accumulation, essential oil content and its major components, phenolic content and antioxidant enzymes. Furthermore, the phytoremediation potential of this species was observed in the presence of the tested metals. When applied in high concentrations all metals caused sharp reduction in the M. leucocephalus growth, however, was observed that Zn stress caused an increase in the content of volatile compounds. Plant exposure of to milder metals concentrations caused less growth reduction and nutritional unbalance M. leucocephalus. In this case, Cd stress stimulate higher production of volatile compounds. No metal treatment alters the essential oils quality. Cd, Cu and Zn was accumulated in higher concentration in the roots, demonstrating the potential of this species to phytostabilization in contaminated environments. The Cd stress caused an increase in total phenolics concentration, while the peroxidases activity and lipid peroxidation was higher in metals stressed plants. / Esp?cies da fam?lia Lamiaceae t?m sido amplamente estudadas, devido as suas propriedades antioxidantes, antimicrobianas e antivirais. Existe interesse cientifico no desenvolvimento de tecnologias para a potencializa??o de sistemas de produ??o das plantas medicinais, tendo em vista que a baixa concentra??o dos compostos bioativos representa um dos maiores obst?culos para a sua explora??o econ?mica. Trabalhos com algumas esp?cies t?m demonstrado que os metais tra?os, como o Cd, Cu e Zn, atuam como eliciadores abi?ticos, influenciando de forma direta na produ??o de subst?ncias bioativas. Martianthus leucocephalus (Mart. ex Benth.) J.F.B. Pastore ? uma esp?cie que produz ?leo essencial rico em formiato de isobornila, com elevada atividade antimicrobiana. Neste trabalho objetivou-se avaliar o efeito do estresse por Cd, Cu e Zn, sobre a esp?cie, quantificando-se o crescimento, ac?mulo de minerais nas diversas partes da planta, teor de ?leo essencial e de seus componentes majorit?rios, teor de compostos fen?licos e de enzimas antioxidantes. Al?m disso, foi verificado o potencial fitorremediador desta esp?cie, na presen?a dos metais testados. Quando aplicados em elevadas concentra??es todos os metais provocaram forte redu??o no crescimento de M. leucocephalus, entretanto, nestas condi??es apenas o Zn provocou incremento no teor dos compostos vol?teis. A exposi??o das plantas desta esp?cie a concentra??es mais amenas dos metais provocou menor redu??o no crescimento e desbalan?o nutricional de M. leucocephalus. Neste caso, apenas o Cd estimulou maior produ??o de compostos vol?teis, mas nenhum tratamento com metal alterou a qualidade dos ?leos essenciais obtidos. As plantas acumularam Cd, Cu e Zn em maior concentra??o nas ra?zes, demonstrando o potencial da esp?cie para a fitoestabiliza??o desses metais em ambientes contaminados. O estresse por Cd provocou aumento da concentra??o de fen?licos totais, enquanto que a atividade das peroxidases e a peroxida??o lip?dica foi maior nas plantas submetidas aos tr?s metais.
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O BARRO NA MÃO DO OLEIRO: RESSIGNIFICAÇÕES E SENSIBILIDADE ATRAVÉS DA CULTURA MATERIAL. / The clay in the potter s hand: representations and sensitivity through material culture.Nóbrega, Viviane Martins de Moura 18 August 2014 (has links)
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Previous issue date: 2014-08-18 / Facing the numerous possibilities of discussions, presented by the material traces of
the Historical Archaeological Site Maria Mendes, located in Campo Limpo, Goias, it
was chosen for this essay the possibility that best represents the context of the site.
The possibility of, through the diversity of printed decoration on the site s pottery,
understanding the decorative expressions as a form of socio-cultural representation,
brokered by the potter, during their life trajectory, from Africa to Brazil, within the
historical context of the Province of Goiás, in the early nineteenth century. Brokered
from their influences, which have been resignified and printed on ceramic through a
sensitive and creative style. Possibility that splits from the main objective, also to
understand the roles of indigenous, African and European influences on the end
result of the product of the potter. Given the presence of Africans signs, belonging to
different groups and there, in the ceramic set, it seems to have found ways to coexist
the identification of decorative expressions belonging to the Guarani people in an
area of the province of Goias historically occupied by the Kayapo Southern people,
two culturally distinct groups, also in view of the similarities between some fragments,
ceramic plates and pots, and the forms and decorations of European crockery and
vessels.
These understandings are against the interdisciplinary way to understand the culture,
proposed by the theories of Cultural History, which enabled a dialogue between
History and Archaeology in a less compartmentalized way or limited to the use of a
science by another one just as a source. / Diante das inúmeras possibilidades de discussões, apresentadas pelos vestígios
materiais do Sítio Arqueológico Histórico Maria Mendes, localizado no município de
Campo Limpo de Goiás, estado de Goiás, foi escolhida para este trabalho a
possibilidade que melhor representa o contexto do sítio. A possibilidade de, através
da diversidade da decoração impressa na cerâmica do sítio, entender as expressões
decorativas como forma de representação sociocultural, agenciadas pelo oleiro, no
decurso de sua trajetória de vida, da África para o Brasil, dentro do contexto histórico
da Província de Goiás, do início do século XIX. Agenciadas a partir de suas
influências, que foram por ele ressignificadas e impressas na cerâmica através de
um estilo sensível e criativo. Possiblidade que se divide, a partir do objetivo principal,
para também entender os papéis das influências indígenas, africanas e europeias
sobre o resultado final do produto do oleiro. Tendo em vista a presença dos signos
africanos, pertencentes a grupos diferentes e que ali, no conjunto cerâmico,
parecem ter encontrado meios de coexistirem, a identificação de expressões
decorativas pertencentes ao povo Guarani em uma área da província de Goiás
historicamente ocupada pelo povo Kayapó do Sul, dois grupos culturalmente
distintos, tendo em vista também as similaridades entre alguns fragmentos, de
pratos e panelas cerâmicas, e as formas e decorações de louças e vasilhas
europeias.
Esses entendimentos vão ao encontro da forma interdisciplinar de entender a
cultura, proposta pelas teorias da História Cultural, que possibilitou um diálogo entre
História e Arqueologia, de uma forma menos compartimentada ou limitada ao uso de
uma ciência pela outra apenas como fonte.
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Assinaturas icnológicas em depósitos glacigênicos do Grupo Itararé no RSLermen, Raquel Elisa 03 1900 (has links)
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Previous issue date: 2006-03 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / A revisão icnotaxonômica da paleoicnofauna Grupo Itararé no RS revelou a presença de uma icnofauna dominada por trilhas de artrópodes, com impressões de repouso e pistas de deslocamento intraestratal de artrópodes e escavações rasas de organismos vermiformes subordinadas, além de icnofábricas de Chondrites-Planolites-Palaeophycus. Duas novas icnoespécies, Cruziana intermittens n. isp. e Tonganoxichnus itararensis n. isp. foram diagnosticadas. A análise das assembléias icnofossilíferas evidenciou a presença duas paleoicnocenoses distintas: (i) Paleoicnocenose A, contendo trilhas de deslocamento de artrópodes e escavações rasas de artrópodes e de organismos vermiformes, vinculada à fácies de ritmitos; e (ii) Paleoicnocenose B, reunindo exclusivamente escavações mais profundas, vinculada à fácies de depósitos heterolíticos. Quatro suítes distintas são observadas na Paleoicnocenose A: (i) suíte MP, contendo Maculichna varia, Protichnites isp., Diplichnites gouldi e Diplopodichnus biformis, com Kouphichnium isp. subordinado, vinculada aos ritmitos do tipo A; (ii) suíte HT, composta por Helmithoidichnites tenuis e Treptichnus pollardi, com Nereites isp. e Tonganoxichnus itararensis n. isp. subordinados, vinculada com os ritmitos do tipo B; (iii) suíte CR, contendo Cruziana problematica, C. intermittens n. isp., Rusophycus carbonarius e Gluckstadtella cooperi, com H. tenuis subordinado, vinculada aos ritmitos do tipo C; e (iv) suíte Dg, monoespecífica para Diplichnites gouldi, preservada em palimpsesto sobre a suíte CR. A Paleoicnocenose B é formada por icnofábrica composta de Chondrites/Planolites, produzida em níveis intermediários do substrato, e Palaeophycus, em níveis mais superficiais. As assinaturas icnológicas registradas sugerem um sistema deposicional estuarino do tipo fiorde, com a zona mais proximal do estuário situada a ENE (região de Cachoeira do Sul) e a mais distal, a SSW (região ao sul de São Gabriel-sudoeste de Lavras do Sul). Os ritmitos do tipo B se concentrariam na região mais proximal, os ritmitos dos tipos A e C se desenvolveriam nas planícies laterais ao corpo d?água e os depósitos heterolíticos, próximos à desembocadura deste, junto ao mar, em águas salobras. O contexto das paleoicnocenoses A e B e seus vínculos faciológicos sugerem representar, respectivamente, uma Icnofácies Scoyenia atípica e uma Icnofácies Cruziana empobrecida. De acordo com o registro global, a presença de G. cooperi, M. varia, T. pollardi e T. itararensis n. isp. nos ritmitos permitem supor uma idade Carbonífero Superior para esses depósitos. / The ichnotaxonomic review of the trace fossils from Itararé Group (Paraná Basin, south of Brazil) in the Rio Grande do Sul State (southernmost Brazil) showed the presence of an ichnofauna dominated by arthropod trackways. Resting traces and intrastratal trails also made by arthropods and shallow burrows produced by soft-bodied organisms are subordinated, as well as a Chondrites-Planolites-Palaeophycus composite ichnofabic. Two new ichnospecies were diagnosed, Cruziana intermittens n. isp. e Tonganoxichnus itararensis n. isp. Two ichnocoenoses were differenciated: (i) Paleoichnocoenosis A, bearing arthropod trackways, resting traces, intrastratal trails and shallow burrows, related to the rhythmite facies; and (ii) Paleoichnocoenosis B, joining exclusively deeper burrows, related to the heterolithic deposit facies. Four distinct suites were observed in Paleoichnocoenosis A: (i) MP suite, having Maculichna varia, Protichnites isp., Diplichnites gouldi and Diplopodichnus biformis, with Kouphichnium isp. subordinated, and related to the rhythmites type A; (ii) HT suite, composed of Helmithoidichnites tenuis and Treptichnus pollardi, with Nereites isp. and Tonganoxichnus itararensis n. isp. subordinated, related to the rhythmites type B; (iii) CR suite, bearing Cruziana problematica, C. intermittens n. isp., Rusophycus carbonarius and Gluckstadtella cooperi, with H. tenuis subordinated, related to the rhythmites type C; and (iv) Dg suite, monospecific to Diplichnites gouldi, superimposed to the CR suite, in palimpsest preservation. The Paleoichnocoenosis B is formed by a composite ichnofabric of Chondrites and Planolites (deeper tier), and Palaeophycus (shallow tier). The recorded ichnological signatures suggest an estuarine, fjord-like depositional setting, the proximal zone extending to ENE (Cachoeira do Sul region) and the distal zone reaching the SSW (south of São Gabriel-southwest of Lavras do Sul). The rhythmites type B are concentrated in the proximal zone, the rhythmites type A and C, in the marginal plains, lateral to the main body water, and the heterolithic deposits characterize the estuary mouth, opening to the sea, under brackish water conditions. The ichnological and faciological characteristics of the paleoichnocoenoses A and B reveal the existence of an atypical Scoyenia Ichnofaceis and an impoverished Cruziana Ichnofacies, respectively, in the studied deposits. According to the global record, the presence of G. cooperi, M. varia, T. pollardi and T. itararensis n. isp. in the rhythmites allows to infer an Upper Carboniferous (Pennsylvanian) age to these rocks.
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Dynamique de la matière organique dissoute colorée et fluorescente en zone lagonaire tropicale dans le Pacifique Sud (Nouvelle Calédonie) : influences climatiques et anthropogéniques / Dynamic of colored and fluorescent dissolved organic matter in a tropical South Pacific area : climatic and anthropogenic impactMartias, Chloé 16 May 2018 (has links)
Le lagon de la Nouvelle Calédonie (Pacifique Sud-Ouest), est drainé par les entrées fluviales et océaniques sous la pression de l’érosion des sols ultramafiques (enrichies en Nickel et Cobalt). Le but de cette thèse était de mieux comprendre les sources et la variabilité spatio-temporelle de la matière organique dissoute colorée (MODC) et fluorescente (MODF) le long de continuum rivière-côte-lagon-large en zone lagonaire tropicale du Pacifique dans un contexte de changement climatique et d’anthropisation locale (activité minière). Les côtes Est et Ouest calédoniennes ont été échantillonnées pendant 1 an et demi et pendant la campagne CALIOPE 3 (côte Est) lors d’un épisode El Niño fort (2015-2016), ponctués de forts épisodes pluvieux. L’analyse parallèle factorielle (PARAFAC) des matrices d’excitation-émission de fluorescence (MEEFs) a abouti à l’indentifications de 5 fluorophores : humique-like marin, 2 tyrosine-like, et tryptophane-like d’origine autochtone issus des compartiments phytoplanctoniques et bactériens, et un fluorophore humique-like d’origine allochtone provenant des rivières drainant les côtes. La MODC à 350 et 442 nm suivait une dynamique fortement dépendante des apports fluviaux pouvant être découplée de la dynamique de la MODF. La MODF sur la côte Est suivait un cycle saisonnier (saison sèche/humide) contrairement à la côte Ouest dépendante de d'évènements pluvieux sporadiques. Des fluorophores (humique, tyrosine et tryptophane-like) ont montré des affinités avec certains métaux traces (Nickel, Manganèse, Cobalt) ce qui a permis de développer une expérience de quenching de fluorescence pour déterminer le pouvoir complexant de la MODF naturelle. / New Caledonia (South-West Pacific) is a tropical area under strong environmental pressure (climate change and local anthropogenic forcing). The aim of this thesis was to gain a better understanding of the colored (CDOM) and fluorescent (FDOM) dissolved organic matter dynamic in the New Caledonia Lagoon where strong ultramafic erosion pressure is associated with trace metals (i.e., nickel, manganese and cobalt). 3D spectrofluorimetry was used to characterize the CDOM/FDOM. The West and East coasts were sampled during one year and a half in a context of El Niño (2015-2016), interrupted by strong rainy events (storms) and during CALIOPE 3 cruise (East coast). A parallel factor analysis (PARAFAC) of EEMF led to the identification of 5 fluorophores: marine humic-like, 2 tyrosine-like and tryptophan-like peaks (T2 peak) from the biological balance between phytoplankton and bacterioplankton and a terrestrial humic-like from rivers draining caledonian coast. The CDOM signal at 350 and 442 nm had a strong dependency on river inputs accentuated during storms and revealed photodegraded CDOM. The FDOM signal in the East showed a seasonal cycle (wet/dry season) contrary to the West coast depending on sporadic rainy events. Data acquired during the CALIOPE 3 were coupled with trace metal concentrations, biogeochemical parameters, and plankton communities. Some fluorophores displayed a preferential association with nickel and cobalt. The complexation capacities of these fluorophores toward trace metals were revealed by a quenching experiment that allowed to derive complexation constants.
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Un concept technologique de trace numérique / A technological concept of digital traceCollomb, Cléo 08 July 2016 (has links)
Cette thèse entend proposer un concept technologique – c’est-à-dire non-anthropocentré – de trace numérique. Il s’agit de rappeler que l’informatique exigeant des objets et des actes qu’ils passent par l’inscription pour exister, les machines computationnelles sont parties prenantes des processus de production des traces numériques, qu’une « sémiotique technologique » permettrait de décrire. L’enjeu d’un tel concept est de mettre en circulation une narration qui ne soit pas de l’ordre de ces discours de fin de monde décrits par Déborah Danowski et Eduardo Viveiros de Castro. Ces discours racontent la vie d’humains réduits à habiter un environnement ontologiquement dévitalisé et artificialisé, comme cela semble être le cas lorsque la valorisation technique et économique des traces numériques débouche sur une « délégation machinique de nos relations » (Louise Merzeau) ou encore sur une « gouvernementalité algorithmique » (Antoinette Rouvroy et Thomas Berns). À partir du moment où il y a des discours de fin de monde cependant, c’est qu’une tentative est à l’œuvre : celle qui consiste à inventer une mythologie adéquate à notre présent, celle qui essaie de dire quelque chose de la fin d’une certaine aventure anthropologique. Et c’est pour participer à cette tentative, tout en cherchant à éviter de contribuer aux discours de fin de monde, qu’une approche technologique des traces numériques à même de faire compter les machines computationnelles est proposée. / This Ph.D. thesis aims at proposing a concept that is technological – inother words, not anthropocentric – of digital traces. The point is that since computational processes require objects and actions to take the form of inscriptions as a condition of their existence, computational machines are fundamentally involved in the process of producing digital traces, which a technological semiotics could describe. What is at stake in the concept we propose is to put into circulation a narration which avoids the theme of “the end of the world” described by Déborah Danowski and Eduardo Viveiros de Castro. These “end of the world” stories evoke the life of human beings who are reduced to living in an environment that is ontologically devitalized and purely artificial, as it seems to be the case when the technical and economic valorization of digital traces has the end result of “delegating our human relations to machines” (Louise Merzeau) or yet again of leading to “algorithmic governmentality” (Antoinette Rouvroy and Berns). When the theme of “the end of the world” raises its head, it means that an attempt is being made : an attempt to invent a mythology appropriate to our present situation, a narration which tries to say something about the end of a certain anthropological adventure. And it is in order to participate in this venture, but seeking to avoid contributing to the theme of “the end of the world”, that we propose a technological approach to digital traces, enabling us to take into account computational machines as a part of the contemporary world.
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Investigations into isotope biogeochemistry of Zn in coastal areas and mangroves / Investigations de la biogéochimie isotopique du Zn en zones côtières et mangrovesFerreira Araujo, Daniel 12 October 2016 (has links)
Les zones côtières du monde entier sont sous fort pression de contamination anthropique comme conséquence de la concentration de la plupart de la population mondiale et des activités économiques le long des côtes et des estuaires. La menace de contaminant sur les écosystèmes rend primordial le développement d'outils capable de détecter les modifications biogéochimiques en vue d'aider dans la prévention, la gestion, et la prédiction de risques dans les études environnementales. Dans ce but, cette thèse étudie la biogéochimie des isotopes du Zinc (Zn) en vue de développer un outil capable de tracer les sources naturelles et anthropiques, d'identifier les processus biogéochimiques et de permettre à la biosurveillance de la contamination par les métaux dans les zones côtières et les mangroves. A cette fin, les compositions isotopiques du Zn ont été déterminées à plusieurs échantillons naturels prélevés dans la baie de Sepetiba (au sud-est du Brésil), un estuaire lagunaire affecté par une côte industrialisée située près de Rio de Janeiro. Cette baie constitue un laboratoire naturel idéal pour valider le système isotopique du Zn. En effet, cette zone héberge des écosystèmes d'intérêt commercial et écologique -estuaire, mangrove, estran- menacés par la contamination d'une ancienne activité de galvanoplastie, et d'autres sources diffuses. Les échantillons collectés comprennent des carottes de sédiments, des sédiments de la superficie des mangroves, des matériaux particulaires en suspension (SPM), des feuilles provenant d'arbres de mangrove, des tissus de mollusques bivalves (huîtres et moules) et des roches. Minéraux de dépôt de Vazante (Brésil) ont été collecté pour representé matière première utilisée par l'industrie de la galvanoplastie. Tout d'abord, un travail initial de laboratoire a établi une méthode exacte et précise pour les déterminations isotopiques Zn en échantillons naturelles par spectrométrie de masse avec plasma couplé par induction et multicollecteur (MC-ICP-MS). Des analyses spatiales et temporelles des compositions isotopiques du Zn des échantillons de sédiments et de roches s'ajustent bien à un modèle de mélange entre trois principales extrémités : i) les matériaux continentaux charriés par les rivières ; ii) les sources marines ; et iii) une source anthropique majeure associée aux anciens déchets de galvanoplastie jetés dans la baie. Les carottes de sédiment collectées dans la vasière ont montré une haute corrélation entre la composition isotopique du Zn et le facteur d'enrichissement du Zn. Ceci suggère : i) une bonne préservation du registre isotopique des sources naturelle et anthropique, ii) l'absence de fractionnement isotopique significatif durant le transport de sédiments ou durant les réactions diagénétiques pos-dépositions dans le système estuarien. / Coastal areas worldwide are under strong pressure from anthropogenic contamination, as most of the global population and of economic activities are concentrated along the coasts and estuaries. The threaten of contaminant releasing into these ecosystems makes imperative the development of tools capable of detecting biogeochemical changes in order to help prevention, monitoring and prediction of risks in environmental studies. In this way, this thesis investigates the isotope biogeochemistry of Zinc (Zn) in order to develop a tool capable of tracing natural and anthropogenic sources, identifying biogeochemical processes and enabling the biomonitoring of metal contamination in coastal areas and mangroves. To this end, Zn isotopes compositions were determined in several natural samples collected from Sepetiba bay (southeastern Brazil), an estuarine-lagoon impacted by an industrialized coastal area near Rio de Janeiro. This bay constitutes an ideal natural laboratory for evaluating the Zn isotopic system to environmental issues, since it hosts important ecosystems of commercial and ecological interest - estuaries, mangroves and tidal flats - threaten by the metal contamination resultant of old electroplating activity and other anthropogenic diffuse sources. The collected samples include sediment cores, surface mangrove sediments, suspended particulate matter (SPM), leaves of mangrove's trees, tissues of bivalve mollusks (oysters and mussels) and rocks. Ores from Vazante deposit, Brazil were collected to represent the raw material used in the old electroplating industry. Firstly, an initial laboratory work established a method for accurate and precise determinations of Zn isotope compositions in natural samples by multi-collector inductively coupled plasma-mass spectrometry (MC-ICP-MS). Spatial and temporal analysis of Zn isotope compositions of sediment and rock samples fits well in a model of mixing between three main end-members: i) continental materials brought via rivers; ii) marine sources; and iii) a major anthropogenic source associated to the old electroplating wastes released into the bay. Sediment cores collected in the mud flat showed high correlation between Zn isotope compositions and Zn enrichment factors, suggesting (i) good preservation of isotopic records of natural and anthropogenic sources and (ii) no significant isotopic fractionation during sediment transport or as a result of diagenetic reactions post-deposition in the estuarine system. The sediment core sampled from a mangrove located in the zone impacted by the old electroplating activity presented levels of Zn up to 4% (dry weight) and preserved the isotopic signatures of electroplating wastes. However, there is evidence that biogeochemical processes triggered by hydrodynamics, bioturbation or rhizosphere processes slightly changed the isotopic signatures in some layers. Calculations based in this mixing model quantified contributions of the major anthropogenic source of Zn, ranging from negligible values in the pre-industrial period to nearly 80% during periods of electroplating activities between the 60's and 90's.
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Remembering without storing: beyond archival models in the science and philosophy of human memoryO'Loughlin, Ian 01 July 2014 (has links)
Models of memory in cognitive science and philosophy have traditionally explained human remembering in terms of storage and retrieval. This tendency has been entrenched by reliance on computationalist explanations over the course of the twentieth century; even research programs that eschew computationalism in name, or attempt the revision of traditional models, demonstrate tacit commitment to computationalist assumptions. It is assumed that memory must be stored by means of an isomorphic trace, that memory processes must divide into conceptually distinct systems and phases, and that human remembering consists in inner, cognitive processes that are implemented by distinct neural processes. This dissertation draws on recent empirical work, and on philosophical arguments from Ludwig Wittgenstein and others, to demonstrate that this latent computationalism in the study of memory is problematic, and that it can and should be eliminated. Cognitive psychologists studying memory have encountered numerous data in recent decades that belie archival models. In cognitive neuroscience, establishing the neural basis of storage and retrieval processes has proven elusive. A number of revised models on offer in memory science, that have taken these issues into account, fail to sufficiently extricate the archival framework. Several impasses in memory science are products of these underlying computationalist assumptions. Wittgenstein and other philosophers offer a number of arguments against the need for, and the efficacy of, the storage and retrieval of traces in human remembering. A study of these arguments clarifies the ways that these computationalist assumptions are presently impeding the science of memory, and provides ways forward in removing them. We can and should characterize and model human memory without invoking the storage and retrieval of traces. A range of work in connectionism, dynamical systems theory, and recent philosophical accounts of memory demonstrate how the science of memory can proceed without these assumptions, toward non-archival models of remembering.
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