Orientador: Roberto Perez Xavier / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Geociências / Made available in DSpace on 2018-08-27T12:52:01Z (GMT). No. of bitstreams: 1 Assis_RafaelRodriguesde_D.pdf: 28529636 bytes, checksum: a178f7c0049490d9875ccc010692fdbb (MD5) Previous issue date: 2015 / Resumo: MINERALIZAÇÕES E FONTE DOS FLUIDOS. A Província Aurífera de Alta Floresta, porção centro-sul do Craton Amazônico, localiza-se entre os limites das províncias geocronológicas Ventuari ¿ Tapajós (1,95-1,8 Ga) e Rio Negro ¿ Juruena (1,8-1,55 Ga), ou entre as províncias tectônicas Tapajós ¿ Parima (2,03-1,88 Ga) e Rondônia ¿ Juruena (1,82-1,54 Ga), a depender do modelo adotado para o cráton. Ela é essencialmente constituída por sequências plutôno-vulcânicas derivadas de diversos arcos vulcânicos amalgamados no decorrer do Paleoproterozóico. No segmento leste da província, na região que compreende as cidades de Peixoto de Azevedo ¿ Matupá ¿ Guarantã do Norte ¿ Novo Mundo (MT), rochas plutônicas e vulcânicas de composição granítica hospedam mais de uma centena de depósitos auríferos concentrados ao longo do Cinturão Peru ¿ União do Norte, de direção NW-SE. Com base na paragênese e estilo do minério, essas mineralizações podem ser agrupadas em três tipologias principais: (1) Au ± Cu disseminados em sistemas graníticos e dominantemente representados por pirita e concentrações variáveis de calcopirita e hematita; (2) Sistemas filonares de Au ± Cu essencialmente constituídos por pirita com calcopirita subordinada; e (3) Au + metais de base confinados a veios e vênulas que truncam sequências vulcano-sedimentares sin- a pós-tectônicas. Neste contexto, três grupos principais de rochas plutônicas podem ser distinguidos: (1) embasamento granítico e granitóides antigos; (2) intrusões graníticas de composição sieno/monzogranítica que hospedam as principais mineralizações auríferas da província; e (3) hospedeiras sub-vulcânicas de composição monzogranítica a tonalítica. No conjunto, essas unidades representam um magmatismo cálcio-alcalino oxidado, hidratado, de médio a alto K, meta- a peraluminoso e ferroso a ligeiramente magnesiano, possivelmente derivado da fusão parcial da crosta inferior (manto metassomatizado) em ambiente de arcos vulcânicos. Embora a principal hospedeira plutônica (Granito Guarantã) exiba importantes características adakíticas, compreende-se que seu magma fonte tenha se formado nas porções profundas da crosta, com plagioclásio instável, mas granada e hornblenda estáveis. Os novos dados U-Pb em zircão (SHRIMP) indicam que as idades de cristalização do embasamento granítico variam de 1.980 ±8,8 Ma (Gnaisse Nova Guarita) a 1.978 ±8,1 Ma (tonalito foliado), enquanto as hospedeiras graníticas teriam se formado entre 1.904 ±4,6 Ma (Granodiorito X1), 1.901 ±6,8 Ma (Tonalito Pé Quente) e 1.863 ±4,8 Ma (Granodiorito Jorge) e as hospedeiras sub-vulcânicas entre 1.774 ±7,5 (Pórfiro União do Norte) e 1.773 ±5,7 Ma (quartzo-feldspato pórfiro X1). Os valores ?Nd(t) (-5,49 a -0.975) e as idades modelo TDM (2,36 a 2,02 Ga) sugerem magmas de derivação mantélica extraídos de fonte paleoproterozóica, em que a cristalização fracionada teria correspondido ao principal vetor de evolução petrogenética e, em menor escala, processos de contaminação crustal. Coletivamente, é proposto que esses litotipos tenham se originado a partir de três estágios magmáticos principais: (1) embasamento granítico e granitóides antigos no Orosiriano; (2) hospedeiras granodiorititicas-tonalíticas durante o Orosiriano tardio; e (3) pórfiros e sub-vulcânicas no Statheriano. Esses eventos estariam respectivamente associados à construção do (A) Arco Magmático Cuiú-Cuiú; (B) Arco Magmático Juruena; e (C) contexto pós-colisional do Arco Magmático Juruena. Neste arcabouço geológico, enquadram-se os depósitos magmático-hidrotermais do Pé Quente, Luizão, X1 e Francisco, correspondentes aos alvos de estudo dessa tese na escala de depósitos. Os depósitos Pé Quente (Suíte Pé Quente, 1,97-1,9 Ga), Luizão (Granito Novo Mundo; 1,97-1,96 Ga) e X1 (Granito Guarantã; 1,9 Ga), representam os principais exemplos de mineralizações de Au ± Cu disseminadas em sistemas graníticos, enquanto o depósito do Francisco (Pórfiro União do Norte; 1,77 Ga) seria o principal representante de mineralizações auríferas filonares associadas a metais de base. As zonas mineralizadas dos depósitos X1 e Luizão estão condicionadas a uma forte alteração fílica (muscovita grossa + quartzo + sulfetos) com abundantes concentrações de pirita, mas variável de calcopirita e hematita. Essas zonas estão circunscritas a uma intensa alteração potássica pervasiva com ortoclásio + microclínio ± hematita. Embora essas alterações também ocorram no depósito Pé Quente, seu minério está temporalmente relacionado tanto a uma alteração sódica precoce quanto à alteração fílica. No depósito do Francisco, contudo, o minério está confinado a veios de quartzo com extensos halos de alteração sericítica com pirita + esfalerita + galena ± calcopirita ±digenita disseminadas. Essas alterações são margeadas por uma forte alteração potássica com ortoclásio ± hematita, a qual está circunscrita a uma ampla zona de alteração propilítica de cunho regional. Assembleias de inclusões fluidas provenientes de cristais de quartzo dos depósitos Pé Quente e X1 indicam a coexistência de duas tipologias principais de fluidos: (1) um fluido aquoso de ampla salinidade (2,1 a 26,1% eq. NaCl) e de baixa a moderada temperatura (126,5°C a 268,4°C), coexistentes com fluidos (2) aquo-carbônicos de baixa salinidade (6,1 a 8,9% eq. NaCl), mas altas temperaturas (251,6° a 334,6°C), indicativas de aprisionamento heterogênio em condições de imiscibilidade em um sistema magmático-hidrotermal profundo. No depósito Luizão, o regime de fluidos é registrado por fluidos (1) aquoso-salinos (33,6-37% eq. NaCl) com temperaturas entre 200° e 280°C; coexistente com (2) fluidos aquosos bifásicos de baixa salinidade (2,5-15% eq. NaCl) e temperatura (95°-185°C), indicativos de processos de separação de fases em nível crustal mais raso quando comparado aos depósitos Pé Quente e X1. E finalmente, no depósito do Francisco, as assembleias de inclusões fluidas indicam fluidos eminentemente aquosos de baixa à moderada salinidade (até 24,7% eq. NaCl) e temperatura (85,3°C a 373,2°C), que exibem grande variação quanto ao grau de preenchimento pela fase de vapor (10-70%), sugestivos de processos de ebulição em nível crustal raso. Adicionalmente, os dados isotópicos para oxigênio, deutério e enxofre indicam forte componente magmática para os depósitos do Pé Quente, Luizão e X1, enquanto que no depósito do Francisco, fluidos eminentemente magmáticos teriam interagido com fluidos externos, possivelmente de origem meteórica. Em virtude das similaridades entre seus principais atributos geológicos, assembleias de inclusões fluidas e dados isotópicos, os depósitos Pé Quente, Luizão e X1 podem ser classificados como similares a depósitos do tipo ouro pórfiro, porém, posicionados em níveis crustais mais profundos do que os clássicos exemplos andinos, enquanto o depósito do Francisco seria equivalente às mineralizações epitermais de sulfetação intermediária. No âmbito dessas mineralizações, são reportadas as primeiras idades Re-Os em sulfetos provenientes das principais zonas auríferas dos depósitos supracitados, assim como as primeiras idades da alteração hidrotermal (40Ar/39Ar) associadas à zona mineralizada do depósito epitermal da província. As idades Re-Os em concentrados de pirita do depósito Pé Quente variam de 1.792 ±9 Ma a 1.784 ±11 Ma (idade modelo: 1.787 ±5,5 Ma), enquanto que para o Luizão elas estão compreendidas entre 1.790 ±9 Ma e 1.782 ±9 Ma (idade modelo: 1.787 ±6,2 Ma). No depósito X1, as idades Re-Os em molibdenita são coincidentes aos casos anteriores: entre 1.787 ±7 Ma e 1,785 ±7 Ma (idade modelo: 1.786 ±5 Ma). No depósito do Francisco, as idades 40Ar/39Ar em alíquotas de sericita oriundas do halo de alteração sericítico fornecem idades entre 1.779 ±6,28 a 1.777 ±6,3 Ma e, portanto, bastante similares aos depósitos disseminados de Au ± Cu. Em adicional, as idades 40Ar/39Ar da alteração fílica do depósito Pé Quente variam de 1.833,6 ±6,2 a 1.830,6 ±6.2 Ma, enquanto que no depósito X1 essas idades estão compreendidas entre 1.733,3 ±6,2 a 1.751,3 ±6,1 Ma. A grande uniformidade isotópica obtida para os depósitos disseminados de Au ± Cu fornece uma excelente idade isocrônica em 1.786 ±1 Ma, com idade modelo em 1.787 ±3,2 Ma, as quais permitem apontar para um único e estreito evento aurífero na Província, centrado no Statheriano e que teria durado aproximadamente 10 Ma. No conjunto, essas idades, portanto, demonstram a contemporaneidade das mineralizações com o alojamento de corpos porfiríticos sub-vulcânicos sin- a pós-colisionais na Província, correlacionados às suítes Colíder (quartzo-feldspato pórfiro X1) e Teles Pires (Pórfiro União do Norte), pertencentes ao terceiro evento magmático da província. Logo, as idades Re-Os diferem substancialmente das idades U-Pb das hospedeiras plutônicas graníticas dos depósitos investigados. Esse fato demonstra não haver qualquer conexão genética entre o plutonismo granítico e processos responsáveis pelas mineralizações auríferas da província, diferentemente dos três eventos auríferos até então propostos para a província: (1) 1,98-1,95 Ga (e.g. depósitos Luizão e Pé Quente); (2) 1,87-1,85 Ga (depósitos X1 e Serrinha) e (3) 1,77-1,79 Ga (depósito do Francisco). Essas idades abrem, portanto, novas perspectivas para a exploração aurífera na Província, visto que unidades vulcânicas e sub-vulcânicas de idade 1,78-1,77 Ga agora se tornam alvos potenciais à exploração / Abstract: The Alta Floresta Gold Province, eastern portion of the Amazon Craton, extends between the Ventuari ¿ Tapajós (1.95 to 1.8 Ga) and Rio Negro ¿ Juruena (1.8 to 1.55 Ga) geochronological provinces, or between the Tapajós ¿ Parima (2.03-1.88 Ga) and Rondônia ¿ Juruena (1.82-1.54 Ga), depending on the model used. The province is mainly composed of arc-type plutono-volcanic sequences amalgamated during the Paleoproterozoic. At the easternmost segment of the province, in region that comprises the districts of Peixoto de Azevedo ¿ Mautpá ¿ Guarantã do Norte ¿ Novo Mundo (MT), a significant number of gold deposits are distributed along a NW-SW striking belt (Peru ¿ União do Norte belt) hosted by plutonic and volcanic rocks of granitic composition. Based on ore and stype paragenesis, these gold mineralizations can be clustered into three main groups: (1) Au ± Cu disseminated within granitic systems and essentially represented by pyrite and variable amounts of chalcopyrite and hematite; (2) Au ± Cu-rich veins mainly composed of pyrite and subordinated chalcopyrite; and (3) vein-type Au + base metals that crosscut sin- to post-collisional volcano-sedimentary sequences. Whitin this context, three major groups of plutonic rocks may be distinguished: (1) basement and old granitoids; (2) granitic intrusions that vary in composition from tonalite to syeno/monzogranite and that host the major gold mineralizations within the province; and (c) subvolcanic hosts of tonalite to monzogranite composition. These units display affinities to the calc-alkaline, oxidized, hydrated, medium to high-K, meta- to peraluminous and ferrous to slightly magnesium (I-type granites), possibly derived from volcanic arc-type setting from partial melting of lower crustal sources (metasomatized mantle). Although the main granite host (Guarantã granite) exhibits an adakite-signature, it is understood that its magma might have been derived from a deep crustal level, with instable plagioclase, garnet and hornblende stable. The new SHRIMP U-Pb zircon ages suggest that the crystallization ages related to the granitic basement range from 1,980 ±8.8 Ma (Nova Guarita gneiss) to 1,978 ±8.1 Ma (foliated tonalite), where those obtained to plutonic granitic host rocks are between 1,904 ±4.6 Ma (X1 granodiorite), 1,901 ±6.8 Ma (Pé Quente tonalite) and 1,863 ±4.8 Ma (Jorge granodiorite), and those related to subvolcanic host rocks vary from 1,774 ±7.5 (União do Norte porphyry) to 1,773 ±5.7 Ma (X1 quartz-feldspar porphyry). The ?Nd(t) (-5.49 to -0.975) and TDM ages (2.36 to 2.02 Ga) are indicative of Paleoproterozoic mantle-derived magmas with fractional crystallization as the main vector of evolution to these lithotyepes, such as crustal contamination in minor importance. Collectively, these lithotypes can be clustered into three main magmatic stages: (1) Orosirian granitic basement and old granites; (2) Late Orosirian granodiorite-tonalite host intrusions; and (3) Statherian porphyries and subvolcanics. These events would related, respectively, the construction of (A) Cuiú-Cuiú magmatic arc; (B) Early Juruena magmatic arc; and (C) Post-collisional Juruena magmatic arc setting. Within this geological context, we have the Pé Quente, Luizão, X1 and Francisco magmatic-hydrothermal gold deposits, the main case of study in this work. The Pé Quente (Pé Quente suite; 1.97-1.9 Ga), Luizão (1.97-1.96 Ga) and X1 (Guarantã granite; 1.9 Ga) deposits represent the major disseminated Au ± Cu mineralization in granitic systems, whereas the Francisco deposit (União do Norte porphyry; 1.77 Ga) would correspond the principal exemple of vein-type gold + base metals. The Luizão and X1 ore-zones are related to a strongly and pervasive phyllic alteration (coarse-grained + quartz + sulfide) wich high concentrations of pyrite but variable chalcopyrite and hematite. These hydrothermal zones are limited by a strong and pervasive potassic alteration with orthoclase + microcline ± hematite. Although these hydrothermal alterations are also found in the Pé Quente deposit, its ore is temporally related both to an early sodic as phyllic alterations. At the Francisco deposit, however, the main ore-zones are restricted to quartz-rich veins with metric sericitic alteration halos (5 to 6 m) with disseminated pyrite + sphalerite + galena ± chalcopyrite ± digenite. Collecvely, these hydrothermal alterations are limited by a regional propylitic alteration. Fluid inclusion assemblages in quartz crystals from X1 and Pé Quente deposits reveal the presence of two types of ?uids: (1) aqueous two-phase inclusions with wide salinity (2.1-26.1 wt.% eq. NaCl) and homogenization temperatures (126.5°C to 268.4°C); and (2) H2O-CO2 inclusions of low salinity (6.1-8.9 wt.% eq. NaCl) and higher temperatures (251.6° to 334.6°C), suggestive of heterogeneous entrapment by immiscibility processes in a deep magmatic-hydrothermal system. At the Luizão deposits, the fluids regime revel the coexistence of two types of aqueous fluids: (1) a high salinity (33.6 to 37 wt% NaCl eq.) fluids represented by halite-bearing fluid inclusions with temperatures that range from 200° to 280°C; and (2) a low salinity (2.5 ¿ 15 wt% NaCl eq.) and lower temperature fluid represented by two-phase inclusions, indicating fluid phase-separation processes at shallower crustal level if compared the Pé Quente and X1 deposits. And finally, at Francisco deposit the fluids are mainly composed of low to moderate salinity (up to 24 wt.% eq. NaCl) and temperature (85.3° to 373.2°C) and salinity aqueous fluid inclusions with heterogeneity in the vapor-phase filling degree (10-70 vol.%), which are suggestive of boiling processes in a shallower crustal leve. Moreover, oxygen, deuterium and sulfur isotope data do indicate a strong magmatic signature to the Pé Quente, X1 and Luizão deposits, whereas in the Francisco deposit, fluids essentially magmatic may have interacted with meteoric fluids. Based on the similarities between the major geological attributes, fluid inclusions assemblages and isotopic data, the Pé Quente, X1 and Luizão deposit can be similar to gold-only, Cu-poor porphyry systems, however, placed within deeper crustal levels than those classically interpreted as andian-type porphyry, whereas the Francisco deposits would be equivalent to polymetallic epithermal deposits of intermediate sulfidation. About these gold mineralizations, this work reports for the first time Re-Os pyrite and molybdenite ages for the Au ± disseminated deposits, such as the firt hydrothermal alteration ages (40Ar/39Ar) related to the ore-zones of the epithermal systems from the province. The Re-Os pyrite ages for the Pé Quente deposit vary from 1,792 ±9 Ma to 1,784 ±11 Ma (model age: 1.787 ±5,5 Ma), whereas those for Luizão deposit are between 1,790 ±9 Ma and 1,782 ±9 Ma (model age: 1,787 ±6.2 Ma). The Re-Os molybdenite ages for X1 deposit are very similar to the previously deposits, because it range from 1,787 ±7 Ma to 1,785 ±7 Ma (model age: 1,786 ±5 Ma). At the Francisco deposit, the 40Ar/39Ar ages from sericite samples from sericitic halo vary from 1,779 ±6.28 to 1,777 ±6.3 Ma, therefore, very similar to those obtained to the Au ± disseminated deposits. Additionally, the 40Ar/39Ar ages to the phyllic alterations from Pé Quente deposit range from 1,833.6 ±6.2 to 1,830.6 ±6.2 Ma, whereas to the X1 deposit these ages are constrained between 1,733.3 ±6.2 to 1,751.3 ±6.1 Ma. The isotopic uniformity of the disseminated Au ± Cu deposits provides an excellent isochronous age at 1.786 ±1 Ma, with model age at 1.787 ±3.2 Ma, suggesting a major and unic Staherian gold metallogenetic event within the Alta Floresta Gold Province that would lasted approximately 10 Ma. These ages allow us to correlate the ore-forming processes with the post-collisional felsic magmatism of the Juruena arc, possibly associated to the emplacement of the Colíder (quartz-feldspat porphyry) and Teles Pires (União do Norte porphyry) suites, belonging to the third magmatic event that took place in the province. Therefore, the Re-Os sulfide ages are substantially different from the U-Pb zircon crystallization ages of the plutonic granitic host rocks. This demonstrates that there is no genetic connection between the emplacement of granitic plutons and the ore-forming processes responsible for the gold mineralization in the province, contrasting, therefore, to the three auriferous events so far proposed to the province: (i) 1.98-1.95 Ga (e.g. Luizão and Pé Quente deposits); (ii) 1.87-1.85 Ga (X1 and Serrinha deposits); and (iii) 1.77-1.79 Ga (e.g. Francisco deposit). These new Re-Os pyrite and molybdenite ages open new perspectives for gold exploration in the province as volcanic and sub-volcanic units of 1.78 to 1.77 Ga now may become prime targets / Doutorado / Geologia e Recursos Naturais / Doutor em Ciências

Dans cette thèse, nous avons étudié le problème de l'estimation de mouvement chez les mammifères et nous proposons que passer à l’échelle des modèles ancrés dans la biologie pour les applications du monde réel peut nous donner de nouvelles perspectives en vision biologique. En utilisant un modèle classique qui décrit l'activité des neurones dans les aires corticales V1 et MT du cerveau des primates, nous avons proposé une architecture montante pour l'estimation de mouvement et l’avons évaluée sur des exemples de référence de vision par ordinateur (une première pour ce type de modèles), révélant des lacunes telles que le manque de sélectivité au niveau des frontières de mouvement et l'absence d'association spatiale du champ de vitesses. Pour y remédier, nous avons proposé deux extensions, une stratégie d’intégration modulée par la forme pour minimiser les erreurs aux discontinuités de texture et un schéma de régression pour le décodage. Ces extensions ont amélioré la précision de l'estimation, mais aussi souligné à nouveau le débat sur le rôle des différents types de cellules dans le codage mouvement, par exemple le rôle relatif des cellules “pattern” par rapport aux cellules “component”. Pour comprendre cela, nous avons utilisé un modèle de champs neuronaux représentant une population de cellules MT pour comprendre le rôle des récurrences. Nos résultats montrent qu'une variété de comportements peuvent être reproduits, ils expliquent les changements dynamiques en fonction des stimuli, et nous conduisent à remettre en cause les régimes élevés d'inhibition généralement choisis dans la littérature. / In this thesis, we studied the problem of motion estimation in mammals and propose that scaling up models rooted in biology for real world applications can give us fresh insights into the biological vision. Using a classic model that describes the activity of directionally-selective neurons in V1 and MT areas of macaque brain, we proposed a feedforward V1-MT architecture for motion estimation and benchmarked it on computer vision datasets (first publicly available evaluation for this kind of models), revealing interesting shortcomings such as lack of selectivity at motion boundaries and lack of spatial association of the flow field. To address these, we proposed two extensions, a form modulated pooling strategy to minimize errors at texture boundaries and a regression based decoding scheme. These extensions improved estimation accuracy but also reemphasized the debate about the role of different cell types (characterized by their tuning curves) in encoding motion, for example relative role of pattern cells versus component cells. To understand this, we used a phenomenological neural fields model representative of a population of directionally tuned MT cells to check whether different tuning behaviors could be reproduced by a recurrently interacting population or if we need different types of cells explicitly. Our results indicated that a variety of tuning behavior can be reproduced by a minimal network, explaining dynamical changes in the tuning with change of stimuli leading us to question the high inhibition regimes typically considered by models in the literature.

Modern technology affects all aspects of human life, and translation is not an exception. The development of translation technology -computer-assisted translation (CAT) and machine translation (MT)- is causing shifts in professional competencies and significant changes in the work of human translators, who are concerned about the future of their profession. Furthermore, insufficient collaboration between translators and technology developers leads to dissatisfaction with translation tools, contempt for machine translation, and mutual misunderstandings. The aim of this master's thesis is to promote the dialogue between professional translators and translation technology experts. First, a questionnaire survey is conducted among translators; then, its results are consulted with experts in translation technology. It is confirmed that the inevitable changes do not mean that the profession will become obsolete, but rather transformed. In addition, there are various possibilities for collaboration between translators and developers. However, for this collaboration to be as effective as possible, it will be necessary to address the differences between the views of both sides.

Conjugated linoleic acid (CLA) exhibits multiple biological and molecular activities that have made it the subject of considerable nutrition-related research. Numerous studies support broad acting anti-tumor effects including anti-inflammatory, anti-proliferation, and pro-apoptosis in a variety of model systems. CLA’s ability to influence multiple tumor promoting pathways, without toxicity, may prove valuable in the chemoprevention of breast cancer. The overall objective of this dissertation research was to investigate the potential of CLA in the chemoprevention of breast cancer in a subgroup of women at risk of developing estrogen receptor (ER) negative disease. Overexpression of either the ERBB2 oncogene or the epidermal growth factor receptor (EGFR) is a common event in ER negative breast cancer. To respond to this association, the stated research objective was pursued in relevant model systems. The primary hypothesis was that CLA would downregulate the ERBB2 receptor in vitro and inhibit mammary tumorigenesis in vivo. The t10c12 CLA isomer significantly reduced ERBB2 protein expression in the ERBB2 overexpressing cell line SKBr3. This was accompanied by a decrease in NFκB nuclear localization, cyclooxygenase-2 (COX2)-derived prostaglandin (PG) E2 production, increased apoptosis, and inhibition of proliferation. In contrast to the in vitro data, however 1% dietary CLA had pro-tumor effects in the PyV-mT transgenic mouse model, Mammary gland whole mounts indicated a significant loss of adipose in the CLA-treated group compared to controls that was confirmed by the downregulation of adipocyte-specific genes including PPARγ and adiponectin. CLA’s effect on the adipose was supported by decreases in fatty acid synthase at the protein and mRNA level. cDNA microarray revealed significant downregulation of cytoskeletal and adhesion-related genes in the CLA-treated group. These data suggest CLA’s combined effect on the adipose and epithelial architecture may have promoted tumor growth in this model While the large body of evidence supporting an anti-tumor effect of CLA can not be discounted, the studies herein demonstrate the complexity of its action that may not be captured in simple model systems. Reports of adverse effects of mixed isomers or the t10c12 purified isomer lend caution to supplementation that is supported by our in vivo data.

The redox properties of Copper (Cu) make it both an ideal cofactor for many enzymes, and, in its free form, a highly toxic molecule capable of stimulating production of reactive oxygen species or binding to protein thiol groups. Therefore, living organisms have evolved homeostatic systems to “handle” Cu avoiding dangerous and wasteful aspecific interactions. These systems comprise uptake, carrier, storage and excretion proteins. The importance of Cu-homeostatic systems was initially discovered in humans where alterations of Cu-excretory proteins were shown to be responsible for two lethal genetic disorders; the Wilson and Menkes diseases. The levels of bioavailable Cu in the aquatic environment is important because concentrations in oceanic waters tend to be minute, whilst in some fresh and coastal waters, particularly around areas of mineral extraction, viniculture and farming operations, concentrations can be excessive. In contrast to terrestrial vertebrates, fish are not only exposed to dietary sources of copper but are also exposed to dissolved ionic copper that may enter via the skin and gills. Indeed, the latter route is important in fish and it has been demonstrated in physiological studies that under conditions of dietary deficiency, fish can satisfy their own body requirements by uptake from water. Therefore, fish must have systems relating to both gill and gut to enable maintenance of body homeostasis of this essential, yet toxic, metal. In an attempt to understand the mechanisms of Cu homeostasis in fish, whether under conditions of deficiency, adequacy or excess, it is essential to consider the expression of known Cu-homeostasis proteins. Thus, cDNAs for sea bream (Sparus aurata) homologues of copper transporter 1 (Ctr1), antioxidant protein 1 (Atox1), Menkes protein (ATP7A), Wilson protein (ATP7B), and metallothionein (MT), which are responsible for the uptake, delivery to the secretory pathway and scavenging of intracellular Cu, were cloned and their mRNA tissue expression levels measured. To investigate the molecular basis of the different homeostatic and toxic responses to waterborne or dietary Cu, sea bream were exposed to sub-toxic levels of Cu in the diet (130 mg/Kg of dry diet) or water (0.3 mg/L) and tissue mRNA and Cu levels were measured. Moreover, to discriminate between the effect of different metals on the transcriptional regulation of Cu homeostasis genes in fish, Sparus aurata fibroblast (SAF1) cells were exposed to sub-toxic levels of Cu (25 μM), Zn (100 μM) and Cd (10 μM). In addition, a microarray was used to gain a broader overview of the transcriptional response of SAF1 cells to Cu (25 μM). Waterborne or dietary Cu resulted in distinct expression profiles of Cu-homeostasis genes and markers of oxidative stress. After dietary exposure, Cu increased in intestine and liver, whilst after waterborne exposure Cu increased in gill and liver. Exposure to dietary Cu resulted in decreases in Ctr1 and ATP7A mRNA in both liver and intestine. Renal Ctr1 levels remained unchanged, whilst ATP7A mRNA decreased. In contrast, waterborne Cu exposure increased intestinal Ctr1 and ATP7A mRNA, and increased renal Ctr1 and decreased renal ATP7A mRNA. Both dietary and waterborne Cu increased ATP7B mRNA in liver. Metallothionein (MT) mRNA increased in liver and gill after waterborne Cu. Glutathione reductase (GR), a marker of oxidative stress, increased expression in liver and gill after waterborne Cu exposure, but decreased in intestine. Thus, exposure to Cu via water or diet has different, often opposite effects on Cu-homeostasis genes. The decrease in expression of both Cu-transport genes in intestine after dietary exposure may indicate a defensive mechanism to limit uptake of Cu. The opposite effects in intestine after waterborne exposure are more difficult to explain, but again may reflect a defence mechanism against excess bloodborne Cu coming from the gill. Since both dietary and waterborne Cu increased Cu levels in liver and increased hepatic ATP7B it is likely that well-characterised mammalian route of Cu excretion to bile is active in sea bream. However, only hepatic Cu derived from gill increased the expression of the stress markers MT and GR. This suggests that Cu is delivered to liver in a different form from gill as that from intestine, the intestinally derived pool being less toxic. Thus the increase in copper transport gene expression in intestine after gill exposure might be a mechanism to enable incorporation of excess bloodborne Cu into the intestinal pathway of Cu delivery to liver, thus minimizing toxicity. The in vitro exposure of SAF1 cells to Cu showed a similar response to liver of fish exposed to waterborne Cu indicating similar Cu availability and complexation. ATP7A mRNA levels were induced by Cu but not by Zn or Cd suggesting Cu-specific regulation. Conversely, MT and GR were induced by all metals tested. The transcriptomic analysis highlighted that the biological processes most significantly affected by Cu were secretion, protein trafficking and stress. Overall, these results show that in fish copper has distinct effects on tissue Cu transporter genes and oxidative stress depending on whether it is taken up via the gill or gut and that intestinal absorption may be required for normal uptake and metabolism of Cu, regardless of the route of uptake. Moreover, changes in mRNA levels indicate that Cu homeostasis genes, at least in fish, may be regulated at the transcriptional level. Although more work needs to be done to identify genes that are robust predictors of Cu toxicity, the microarray results presented here show a clear transcriptional fingerprint which may characterize Cu toxicity in fish.

Thèse numérisée par la Direction des bibliothèques de l'Université de Montréal.

Les effondrements de flanc déclenchent de larges avalanches de débris et glissements de terrain, provoquant ainsi une modification de la pente du volcan et altérant le paysage. Les différents types de volcans subissent des effondrements de flanc lors de leur développement. Aux Philippines, par exemple, les volcans présentant des brèches sont les cônes, sub-cônes et volcans massifs. Les avalanches de débris affectent les édifices volcaniques et non-volcaniques ; leur étude constitue donc un enjeu primordial pour l’évaluation des risques naturels. Les dépôts d’avalanche de débris (DAD) présentent des structures de surface et internes, des morphologies et des textures pouvant être utilisées pour déterminer le type de transport, les mécanismes de déformation et les vitesses d’emplacement de l’avalanche de débris. Cependant, sur le terrain, les DAD sont souvent vastes et chaotiques, ainsi l’apport de la télédétection complète l’étude de terrain en apportant une vision d’ensemble de l’avalanche. Notre étude s’intéresse à la structure et morphologie des DAD par l’utilisation de modèles analogiques et en contexte naturel via l’étude du Mt Iriga et Guinsaugon aux Philippines et à travers d’autres sites dans le monde (Mt Meager, Canada ; Storegga Slide, Norvège). L’étude de la vitesse de mise en place, de la dynamique et des mécanismes de déformation des avalanches de débris s’est faite via la modélisation analogique. Il apparait ainsi que la formation de “hummocks” est un processus clé dans la structuration des DAD. Les “hummocks” sont des parties massives du volcan arrachées lors de l’avalanche de débris et qui se disloquent au fur et à mesure de son avancée. Cette dislocation des “hummocks” s’effectue via l’apparition de failles normales à fort pendage qui fusionnent avec les zones de cisaillement à faible pendage situées à la base du glissement. Les “hummocks” fournissent des informations sur les conditions de transport et la composition initiale de l’avalanche. Leur géométrie (taille et forme), leur structure interne et leur distribution spatiale sont des indicateurs de la vitesse du développement de l’avalanche. Ils permettent d’interpréter sa dynamique de mise en place. Les expériences analogiques utilisant une rampe courbée montrent le développement de zones d’accumulation et d’épaississement à l’endroit où les matériaux atteignent une surface de dépôt à faible pente. Les expériences avec des rampes rectilignes montrent de plus long glissement. L’extension de ces avalanches est accommodée par des structures en horst et graben ainsi qu’en transtension. Le dépôt consécutif à l’avalanche peut ê remobilisé lors d’effondrements secondaires. L’ensemble de ces expériences montre que la morphologie de la surface de glissement influence les mécanismes de mise en place, l’extension spatiale et la structure de l’avalanche. La cartographie structurale et morphologique acquise par télédétection ainsi que la description de caractéristiques récurrentes sur plusieurs DAD, difficiles d’accès et jusqu’ici non cartographiés (Süphan Dağı (Turkey), Cerro Pular-Pajonales (Argentina), and Tacna (Peru), a permis de préciser les scénarios, les causes et les facteurs de mise en place des DAD. La cartographie des DAD est une étape nécessaire pour retracer les évènements passés et estimer les risques naturels dans une zone spécifique. L’identification et la description des morphologies et structures des DAD devraient permettre la compréhension des mécanismes de mise en place de l’avalanche. / Flank collapse generates avalanches and large landslides that significantly change the shape of a volcano and alter the surrounding landscape. Most types of volcanoes experience flank collapse at some point during their development. In the Philippines, for example, the numerous volcanoes with breached edifices belong to the cone, subcone, and massif morphometric classes. Debris avalanches occur frequently on both volcanic and non-volcanic terrains making it an important geologic event to consider for hazard assessment. Debris avalanche deposits (DAD) preserve surface and internal structures, morphology, and texture that can be used to determine transport type, deformation history, causal mechanism, and emplacement kinematics. However, natural DAD are often too vast and chaotic-seeming in the field so that structural and morphological mapping by remote sensing is a good complement to studying them. This study describes and analyses recurrent structural and morphological features of analogue models and natural DAD at Mt Iriga and Guinsaugon (Philippines), and uses several other examples at Mt Meager (Canada), and Storegga Slide (Norway). The study explores the use of analogue models as landslide kinematics, dynamics, and emplacement and causal mechanism indicators. Hummocks are identified as a key structural element of DAD. Hummocks, a major DAD topographic feature, are formed as the mass in motion slides and evolves by progressive spreading and break up. Internally, high angle normal faults dissect hummocks and merge into low angle shear zones at the base of the slide zone. Hummock size distribution is related to lithology, initial position, and avalanche kinematics. Hummocks provide information on the transport conditions and initial composition of the landslide. Their geometry (size and shape), internal structures, and spatial distribution are kinematic indicators for landslides from development until emplacement and provide a framework for interpreting emplacement dynamics. Experiments with curved analogue ramps show the development of an area of accumulation and thickening, where accelerating materials reach a gently sloped depositional surface. Experiments with straight ramps show a longer slides with continued extension by horst and graben structures and transtensional grabens. A thickened mass is found to subsequently remobilise and advance by secondary collapse. This set of experiments show that failure and transport surface morphology can influence the emplacement mechanism, morphology, and avalanche runout. Structural and morphological mapping by remote sensing, and description of recurrent features at the remote and previously unmapped Süphan Dağı (Turkey), Cerro Pular-Pajonales (Argentina), and Tacna (Peru) DAD suggest scenarios, causes, triggering and emplacement mechanisms of these DAD. These are used to explain their avalanche kinematics and dynamics. Mapping DAD is a necessary step for identifying past events and existing hazards in specific areas. Identifying and describing the DAD structures and morphology will help understand the kinematics and dynamics of the emplaced avalanches.

Orientador: Iveraldo dos Santos Dutra / Banca: Ériklis Nogueira / Banca: Vera Cláudia Magalhães Curci / Banca: Antônio Sérgio Ferraudo / Banca: Luís Antônio Mathias / Resumo: A bovinocultura é a principal atividade econômica desenvolvida no pantanal de Mato Grosso do Sul. Reconhecida como patrimônio da humanidade e reserva da biosfera, a região é importante fornecedora de bezerros de corte. As medidas de ordem sanitária compulsórias adotadas pelos produtores obedecem as diretrizes dos programas oficiais que contemplam a febre aftosa, brucelose, tuberculose e a raiva. No entanto, a maioria das ações de saúde animal são voluntárias e dependem da iniciativa e interesse dos produtores. Com o objetivo de avaliar a percepção de risco entre produtores de bovinos de corte em relação a diversas práticas sanitárias, foram entrevistados gestores de 31 fazendas nas sub-regiões Paiaguás, Nhecolândia, Abobral, Paraguai e Porto Murtinho, totalizando 387.908 ha e 204.254 bovinos. Para análise dos dados relacionados à percepção de risco e práticas sanitárias foram considerados os fatores socioeconômicos: escolaridade, número de animais e tempo na atividade. Como fatores de percepção de risco utilizou-se: assistência veterinária, conhecimento da veiculação hídrica de doenças, treinamento de vacinadores, procedimento em caso suspeito de febre aftosa, conhecimento e obediência ao período de carência de produtos veterinários e destinação de cadáveres. Os resultados apontam correspondência entre fatores socioeconômicos e o modelo de assistência veterinária, o conhecimento de que a água pode transmitir doenças aos animais e o treinamento dos vacinadores. Não houve correspondência do perfil socioeconômico e o procedimento em caso de animal suspeito de febre aftosa no rebanho e a destinação de cadáveres. Produtores com menor escolaridade, menor número de animais e menor tempo na atividade não possuem assistência veterinária ou possuem esporadicamente, desconhecem os riscos da veiculação hídrica de doenças, não realizam treinamento de vacinadores, desconhecem e tendem ... / Abstract: The cattle industry is the main economic activity developed in the Pantanal of Mato Grosso do Sul. Recognized as a world heritage and biosphere reserve, the region is a major supplier of beef calves. The measures of compulsory health requirements adopted by the producers meets the guidelines of the official programs including foot-and-mouth disease, brucellosis, tuberculosis and rabies. However, most animal health actions are voluntary and depend on the initiative and interest of producers. In order to assess the perception of risk among beef cattle producers regarding the various health practices, the managers of 31 farms were interviewed in subregions Paiaguás, Nhecolândia, Abobral, Paraguai and Porto Murtinho, totaling 387.908 ha and 204.254 cattle. To analyze the related data of risk perception and health practices were considered socioeconomic factors: schooling, number of animals and length of service. The perceived risk factors were used: veterinary care, knowledge of waterborne diseases, vaccinators training, procedure in suspected case of food-and-mouth disease, knowledge and obedience to the grace period of veterinary products and disposal of corpses. The results indicate correspondence between socioeconomic factors and the model of veterinary care, the knowledge that water can transmit diseases to animals and the training of vaccinators. There was the correlation of the socioeconomic profile and the procedure in case of food-and-mouth disease suspected animals in the herd and the disposal of corpses. Producers with less schooling, fewer animals and less time in the activity have no veterinary care or have sporadically, unaware of the risks of waterborne diseases, don't develop vaccinators training, unaware and trend not to obey grace periods of veterinary products. In this condition, are very vulnerable about pet health, occupational health and environmental / Doutor

Orientador: Marcos Rogério André / Coorientador: Rosangela Zacarias Machado / Banca: Estevam Guilherme Lux Hoppe / Banca: Darci Moraes Barros-Battesti / Banca: Heitor Miraglia Herrera / Banca: Isabel Kinney Ferreira de Miranda Santos / Resumo: Poucos são os estudos acerca da diversidade genética de Anaplasma marginale nos rebanhos bovinos brasileiros, principalmente no que diz respeito a bovinos de corte. O presente estudo teve como objetivo avaliar a diversidade genética de A. marginale, com base nos genes msp1α e msp4, em Bos taurus indicus amostrados no Pantanal brasileiro. Alíquotas de sangue com e sem EDTA foram colhidas de 400 bovinos (200 vacas e 200 bezerros) em cinco propriedades de cria e recria extensiva. Enquanto as amostras de soro foram submetidas ao Ensaio Imunoenzimático Indireto (iELISA) para detecção de anticorpos IgG anti-A. marginale, amostras de sangue total foram submetidas à avaliação do hematócrito e confecção de esfregaços sanguíneos corados pelo Giemsa, PCR em tempo real quantitativa (qPCR) baseada no gene msp1β, semi-nested (sn)PCR baseada no gene msp1α e PCR convencional (cPCR) baseada no gene msp4 para A. marginale. Os produtos amplificados nos ensaios de snPCR e cPCR foram purificados e sequenciados pelo Método de Sanger. Sequências do gene msp1α foram submetidas à análise de diversidade pelo software RepeatAnalyser. Sequências do gene msp4 foram submetidas à análise de distância Network pelo software Splitstree e de genótipos pelo Software DnaSP5 e PopART. Cinco animais (duas vacas e três bezerros) apresentaram corpúsculos de A. marginale em esfregaços sanguíneos. As frequências de animais positivos pelo iELISA, qPCR e snPCR foram de 72,25% (289/400), 56,75% (227/400) e 22,9% (52/227)... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: There are few studies about the genetic diversity of Anaplasma marginale in Brazilian cattle herds, especially with regard to beef cattle. The present study aimed to evaluate the genetic diversity of A. marginale based on the msp1α and msp4 genes in Bos taurus indicus, sampled in the Brazilian Pantanal. Blood aliquots with and without EDTA were collected from 400 cattle (200 cows and 200 calves) in five extensive breeding and rearing properties. While the serum samples were submitted to the Indirect Immunoenzyme Assay (iELISA) for the detection of anti-A. marginale IgG antibodies, whole blood samples were submitted to the evaluation of hematocrit and Giemsa-stained blood smears, quantitative real-time PCR (qPCR) based on the msp1β gene, semi-nested (sn) PCR based on the msp1α gene and conventional PCR (cPCR) based on the msp4 gene for A. marginale. The amplified products obtained in the snPCR and cPCR assays were purified and sequenced by the Sanger Method. Sequences of the msp1α gene were submitted to diversity analysis by the RepeatAnalyser software. msp4 gene sequences were submitted to Network distance analysis using the Splitstree software and genotypes analysis by the DnaSP5 and PopART software. Five animals (two cows and three calves) presented A. marginale corpuscles in blood smears. The frequencies of iELISA positive animals, qPCR and snPCR were 72.25% (289/400), 56.75% (227/400) and 22.9% (52/227), respectively. The iELISA and qPCR tests showed weak kappa concordance. Cows (154/200) were statistically more seropositive than calves (135/200) (P <0.05). In the qPCR, the number of calves (138/200) and mean value of quantification (1.3 x 106 copies msp1α A. marginale/μL) were higher when compared to those found for cows (89/200; 3.9 x 104) (P <0.05). The rickettsemia estimated by qPCR showed no corr... (Complete abstract click electronic access below) / Doutor

Orientadora: Patrícia Pasquali Parise Maltempi / Coorientadora: Sandra Mariotto / Banca: Luciana Bolsoni Lourenço Morandini / Banca: Diogo Cavalcanti Cabral de Mello / Resumo: A família Loricariidae é uma das mais diversificadas da ordem Siluriformes, com espécies distribuídas entre sete subfamílias: Hypoptopomatinae, Loricariinae, Hypostominae, Neoplecostominae, Lithogeninae, Delturinae e Ancistrinae. As espécies do gênero Ancistrus Kner, 1854, pertencem à subfamília Ancistrinae, têm mostrado grande variação cariotípica, além de características interessantes do ponto de vista citogenético como a presença de cromossomos sexuais e polimorfismos cromossômicos. Desta forma o objetivo do presente trabalho foi caracterizar os cromossomos de quatro espécies do gênero Ancistrus (Ancistrus sp. 1 "cupim", Ancistrus sp. 2 "cupim", Ancistrus sp. "mutuca" e Ancistrus sp. "soberbo") pertencentes à bacia do Paraguai utilizando técnicas de citogenética clássica e molecular para melhor compreensão da evolução cariotípica dessas espécies. As espécies estudadas apresentaram número diploide variando de 2n=42 a 2n=54, NOR localizadas em regiões pericentroméricas e terminais, além de heteromorfismo de tamanho dessas regiões (NOR) em um dos homólogos nas quatro espécies estudadas. O bandamento C mostrou presença de pouca heterocromatina com exceção das espécies Ancistrus sp. 2 "cupim" e Ancistrus sp. "soberbo" que apresentaram dois blocos grandes de heterocromatina em um par de cromossomos, tanto nos machos quanto nas fêmeas. Um exemplar fêmea da espécie Ancistrus sp. 1 "cupim" também apresentou um bloco grande de heterocromatina em um dos homólogos do par 7, sendo esses resultados indicativos de provável relação entre esses blocos de heterocromatina e a diferenciação de cromossomos sexuais. Os resultados obtidos pela técnica de FISH utilizando sondas de DNAr 18S e 5S mostraram que o DNAr 18S está localizado na mesma região da NOR, o DNAr 5S ... (Resumo completo, clicar acesso eletrônico) / Abstract: The Loricariidae family is one of the most diversified of the Siluriformes order, with species distributed in seven subfamilies: Hypoptopomatinae, Loricariinae, Hypostominae, Neoplecostominae, Lithogeninae, Delturinae and Ancistrinae. The species of the genus Ancistrus Kner, 1854, belong to the subfamily Ancistrinae, have shown great karyotype variation, and interesting features of the cytogenetic point of view as the presence of sex chromosomes and chromosome polymorphisms. Thus the aim of this study was to characterize the chromosomes of four species of Ancistrus genus (Ancistrus sp. 1 "cupim", Ancistrus sp. 2 "cupim", Ancistrus sp. "mutuca" and Ancistrus sp. "soberbo") belonging to Paraguay basin using techniques of classical and molecular cytogenetics to better understand the karyotype evolution of these species. The species showed diploid number ranging from 2n = 42 to 2n = 54, NOR located in pericentomeric and terminal regions, and these regions size heteromorphism (NOR) in one of the homologous in the four species. The C-banding showed the presence of few heterochromatin with the exception of species Ancistrus sp. 2 "cupim" and Ancistrus sp. "soberbo" that had two large blocks of heterochromatin in a pair of chromosomes in both males and females. An exemplary female of the species Ancistrus sp. 1 "cupim" also presented a large block of heterochromatin in one of the pair of 7 homologous, and these results indicating probable relationship between these heterochromatin blocks and differentiation of sex chromosomes. The results obtained by FISH technique using probes 18S rDNA and 5S showed that the 18S rDNA is located in the same region of NOR, the 5S rDNA is distributed in four and five chromosome pairs and double FISH showed colocalization of these genes. However of Ancistrus species sp. 2 "cupim" and Ancistrus sp. ... (Complete abstract click electronic access below) / Mestre