Ce travail de thèse a pour objectif de développer une méthodologie permettant de prédire l’impact environnemental des futurs projets miniers, dès l’étape d’exploration. Le drainage minier acide, connu comme le principal problème environnemental des gisements sulfurés, se produit lors de l’oxydation des sulfures par l’oxygène et l’eau. Des échantillons de sulfures et sulfosels ont été soumis à des tests géochimiques afin d’étudier leur taux de réactivité. Les minéraux ont été classés par ordre décroissant: gersdorffite > pyrrhotite > arsénopyrite > Ni-pyrite > Ni-pyrrhotite > Fe-sphalérite > pyrite > galène > chalcopyrite. L’influence des interactions galvaniques sur le taux de réactivité de la pyrite, la chalcopyrite et la sphalérite a été étudiée. La pyrite est protégée galvaniquement en présence de chalcopyrite mais n’est pas complètement protégée en présence de sphalérite. Des mélanges synthétiques de minéraux purs ont permis la modification du calcul de potentiel de génération d’acidité par l’ajout d’un facteur cinétique, basée sur les équations de Paktunc (1999) et Bouzahzah et al. (2013). Dix minerais polymétalliques et aurifères ont été caractérisés selon une méthodologie pluridisciplinaire. La caractérisation minéralogique des minerais a permis de connaître leur composition minéralogique quantitative et de détecter les éléments contaminants ainsi que leur spéciation. Une méthode automatisée de quantification minéralogique basée sur la microscopie optique multispectrale a été développée. Cette innovation vise à développer la microscopie optique pour des applications métallurgiques et environnementales de routine / This thesis proposes the implementation of a reliable methodology, based on the characterization of ores at the exploration stage. The main environmental issues for the mining industry are acid mine drainage and contaminated neutral drainage. Sulfides and sulfosalts, when in contact with water and oxygen, oxidize at different rates, resulting in the production of acid and release of various contaminants. Samples of pure sulfides were submitted to geochemical testing to determine their oxidation rates. The pure minerals can be ordered from the highest to the lowest reactivity as: gersdorffite > pyrrhotite > arsenopyrite > Ni-pyrite > Ni-pyrrhotite > Fe-sphalerite > pyrite > galena > chalcopyrite. Galvanic interactions between pyrite, chalcopyrite, and sphalerite were geochemically investigated. Pyrite was galvanically protected in presence of chalcopyrite, and partially protected in presence of sphalerite. Five synthetic tailings, simulating realistic tailings sulfides compositions, were prepared to compare geochemical behaviors and produce a better assessment of the acid-generation potential (AP). A new method is proposed by adding a kinetic factor. Ten polymetallic and gold sulfide ores were fully characterized with multidisciplinary techniques. Mineralogical investigations allowed for the mineralogical quantification of the ores, and for the knowledge of trace elements and their speciation. A method was developed to automatically quantify sulfides by multispectral optical microscopy. Detailed mineralogical work can save time and money and allows detecting the problems at the beginning of mining developments, improving mine waste management and mine closure planning

Made available in DSpace on 2014-06-11T19:27:14Z (GMT). No. of bitstreams: 0 Previous issue date: 2008-02-21Bitstream added on 2014-06-13T20:55:56Z : No. of bitstreams: 1 santos_rb_me_ilha.pdf: 887891 bytes, checksum: 9cff877681cee249ea6c3466ef38a6ed (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Este trabalho tem como propósito projetar controladores para aplicação em tempo real em uma estrutura flexível, objetivando a redução de vibração estrutural. Os controladores são projetados segundo o enfoque de otimização convexa, com formulações envolvendo desigualdades matriciais lineares (LMIs). Duas diferentes sínteses de realimentação são consideradas. A primeira é o projeto de controladores por realimentação de estados, estimados por um observador. A segunda metodologia é baseada no controle H∞ via realimentação do sinal de saída. O modelo matemático da estrutura, usado no projeto dos controladores, foi obtido utilizando o método de Lagrange. A estrutura considerada representa um modelo de um edifício flexível controlado por uma massa móvel (Active Mass Damper -AMD) localizada no topo. A estrutura é submetida a dois tipos de excitações, sísmica e senoidal. Uma mesa de vibração (Shake Table) foi usada para aplicar as excitações. Para rodar o experimento de controle foi usado uma placa de aquisição (MultiQ - PCI) e o software de controle Wincon. Os controladores foram desenvolvidos usando o Simulink e executado em tempo real usando o Wincon. Testes experimentais foram realizados para comprovação e avaliação das metodologias propostas. / The proposal of this work is to design real time controllers for application in flexible structure, aiming the structural vibration reduction. The controllers are designed by convex optimization involving linear matrix inequalities (LMIs) approaches. Two different methodologies to feedback the system are explained. The first one is the design controller by state feedback based on observer. The second one is based on H∞ output feedback control. The mathematical model of the structure, used in the controller design, was obtained by Lagrange’s method. The structure can represent a flexible building, and it is controlled by a driving mass located at the top. The structure is submitted to seismic and sinusoidal excitations. A vibration table (Shake Table) was used to apply the excitations. The experimental tests were realized using an acquisition board (MultiQ - PCI) and the Wincon control software. The controllers were developed using Simulink, and it run in real time using the Wincon software. Experimental tests were accomplished to validate and evaluate the proposal methodologies.

A Degeneração da Mácula Relacionada a Idade (DMRI) acomete pessoas com mais de 50 anos, comprometendo gravemente a visão. Desde 2005, têm-se sugerido uma correlação entre DMRI e o polimorfismo Y402H do Fator H (FH). Os mecanismos pelos quais a proteína FH participa da etiopatogenia dessa doença têm sido alvo de muitos estudos, desde então. Neste trabalho, investigamos a correlação entre esse polimorfismo e a expressão de proteínas da via alternativa e parâmetros do perfil lipídico de pacientes com DMRI. As concentrações de FH, Fator B, C3 e Proteína C-reativa foram semelhantes entre os grupos controle e paciente. As concentrações de Fator D e os autoanticorpos encontravam-se reduzidos nos pacientes; enquanto Fator I e os demais parâmetros do perfil lipídico estavam aumentados nesses pacientes. A variante Y402 aparentemente aderiu melhor à superfície das leptospiras (superfície ativadora da via alternativa) em relação à variante H402, mas não houve diferença entre as variantes em relação à ligação a células endoteliais (superfície não ativadora). / Age-related Macular Degeneration (AMD) affects people over 50 years, and severely prejudice the vision. Since 2005, it has been suggested a correlation between AMD and the Y402H polymorphism of Factor H (FH). After this, the mechanisms by which FH protein participates in the pathogenesis of this disease have been extensively studied. In this study, we investigated the correlation between this polymorphism and expression of proteins of the alternative pathway and lipid profile of patients with AMD. The concentrations of FH, Factor B, C3 and C-reactive protein were similar between the control and patient groups.Factor D concentrations and autoantibodies levels were reduced in patients, while Factor I concentrations and the levels of the other parameters of lipid profile were increased in these patients.Apparently, Y402 variant displays better adhesion to the surface of Leptospira (alternative pathway activating surface) than the H402 variant, but no difference between the variants of the linkage to endothelial cells (non-alternative pathway activating surface).

Les rétinopathies ischémiques et la forme humide de la dégénérescence maculaire liée à l’âge (DMLA) sont la principale cause de malvoyance respectivement chez les personnes en âge de travailler et les personnes agées. Les néovascularisations choroïdiennes (NVC) et rétiniennes et l’œdème maculaire associés à ces pathologies sont traités à l’aide de biomolécules qui ciblent uniquement la voie de signalisation des VEGF. Le développement de thérapies indépendantes de cette voie permettrait d’offrir aux patients résistants aux anti-VEGF une alternative thérapeutique pour préserver leur vision. Les intégrines αvβ3 et αvβ5, impliquées dans la néovascularisation oculaire, apparaissent ainsi comme une cible alternative intéressante. La Lébécetine (LCT), une lectine de type-C, de 30 kDa et de structure hétérodimèrique issue de venin de serpent Macrovipera lebetina interagit spécifiquement avec les intégrines α5β1 et αvβ3, αvβ5. La LCT a une activité anti-angiogénique in vitro sur des cellules endothéliales microvasculaire du cerveau humain (HBMEC) et in vivo sur le modèle de la membrane chorioallantoïde du poulet (CAM). Afin d’étudier son effet sur la néovascularisation oculaire, nous avons eu recours aux modèles d’angiogenèse ex vivo utilisant des explants aortique ou choroïdien cultivés en présence de LCT, puis son effet a été évalué in vivo dans un modèle de NVC chez la souris et également sur la néovascularisation rétinienne dans le modèle de rétinopathie induite par l’oxygène (RIO). Nos données démontrent qu’une injection unique de LCT est capable de réduire la NVC et rétinienne dans ces modèles sans affecter les vaisseaux quiescents matures indiquant un bon profil d’innocuité. / Ischemic retinopathies and the wet form of age-related macular degeneration (AMD) are characterized by devastating angiogenesis responsible for the majority of irreversible blindness. Current therapies include use of anti-VEGF agents to reduce choroidal neovascularization and edema. These treatments are effective in most cases, but spontaneous or acquired resistance to anti-VEGF highlight a need for additional alternative therapies. In recent years, pharmacological inhibition of αvβ3 and αvβ5, which regulate endothelial cell proliferation and stabilization, have emerged as new therapeutic tools for the treatment of these diseases. Lebecetin (LCT), a 30-kDa heterodimeric C-type lectin that is isolated from Macrovipera lebetina venom, interacts with α5β1 and αv-containing integrins (αvβ3, αvβ5). We previously showed that LCT has an anti-angiogenic effect in vitro on human brain microvascular endothelial cells (HBMEC) and in vivo in a chick chorioallontoic membrane assay (CAM). To evaluate the inhibitory effect of LCT on ocular angiogenesis, we cultured aortic and choroidal explants in the presence of LCT and analyzed the effect of LCT on choroidal neovascularization in the mouse CNV model and on retinal neovascularization in the oxygen induced retinopathy (OIR) model. Our data demonstrated that a single injection of LCT efficiently reduced choroidal and retinal neovascularization in these models with no significant effect on mature blood vessels predicting a good safety profile.

Waste rocks (WRs) from coal mining and fly ash (FA) from coal combustion were studied to determine the potential of the WRs to generate AMD, FAs to neutralise it and estimate their impacts on environment. The ultimate goal was to develop a methodology based on co-disposal to mitigate the environmental problems associated to both wastes. Two methods for co-disposal were tested: i) Mixing WRs and FAs and ii) covering WRs with FAs. WRs were sampled from the Lakhra coal mines in Pakistan (PK), which has an estimated coal reserves of 1.3 Btonne, varying from lignite to sub-bituminous quality. The FA was sampled from a power plant utilising coal from Lakhra coal mines and is situated in close vicinity (15km) of the mine site. For comparative purposes a bituminous FA from Finland (FI) and biomass FA from Sweden (SE) were also characterised. The WRs and FA samples were characterised by mineralogical and geochemical methods. Besides organic material (coal traces), quartz, pyrite, kaolinite, hematite, gypsum and traces of calcite, lime, malladerite, spangolite, franklinite and birnessite were identified in WRs by XRD. The major elements Si, Al, Ca and Fe were in the range (wt. %) of 8 – 12, 6 – 9, 0.3 – 3 and 1 – 10, respectively, with high S concentrations (1.94 – 11.33 wt. %) in WRs. The AMD potential of WRs ranged from -70 to -492 kg CaCO3 tonne-1. All FAs contained quartz, with iron oxide, anhydrite and magnesioferrite in PK, mullite and lime in FI and calcite and anorthite in SE. The Ca content in SE was 6 and 8 times higher compared to PK and FI, respectively. FAs were enriched in As, Cd, Co, Cr, Cu, Hg, Ni, Pb and Zn compared to continental crust. The acid neutralising potential of PK was equivalent to 20 kg CaCO3 tonne-1 compared to 275 kg CaCO3 tonne-1 (SE) and 25 kg CaCO3 tonne-1 (FI). During the period of 192 days in weathering cell experiments (WCE), the pH of leachates from most acidic WRs was maintained from 1 to 2.5, whereas, the less acidic WRs produced leachates of mildly acidic (2.7) to neutral (7.3) pH. The leachates from very acidic WRs ranged in the concentrations of Fe, SO24− and Al from mg L-1 to g L-1. The samples were subjected to column leaching experiments (CLE) in which mixture (FA:WR; 1:3) and cover (FA:WR; 1:5) cases were mimicked (with 10mm particle size) and effects of particle size (2, 5 and 10mm) on element leaching were studied. Despite having the lowest acid-neutralisation potential compared to FI and SE, co-disposal of PKFA as mixture readily provides acid buffering minerals, resulting in better start-up pH conditions and leachate quality. However, acidity produced by secondary mineralisation contributes towards the acidification of the system, causing stabilisation of pH at around 4.5−5. Secondary mineralisation (especially Fe- and Al-mineral precipitation) also removes toxic elements such as As, Pb, Cu, Zn, Cd, Co, Ni and Mn, and these secondary minerals can also buffer acidity when the pH tends to be acidic. In contrast, the pH of the leachates from the PKFA cover scenario gradually increased from strongly acidic to mildly acidic and circumneutral along with decrease in EC and elemental leaching in different WRs. Gradually increasing pH can be attributed to the cover effect, which reduces oxygen ingress, thus sulphide oxidation, causing pH to elevate. Due to the fact that pH~4–5 is sufficient for secondary Fe- and Al-mineral precipitation which also removes toxic elements (such as Cd, Co, Cu, Zn and Ni) by adsorption and/or co-precipitation, the FA cover performs well enough to achieve that pH until the conclusion of the CLE. However, due to the slower reactivity of the buffering system (additional to the initial flush-out), leaching in the beginning could not be restricted. The co-disposal of FA as cover and/or mixture possesses potential for neutralisation of AMD and improving leachate quality significantly. Particle size of the WRs affected the leaching of the sulphide related elements (such as Fe, S, Zn, Co, Cr, Cu, Mn and Ni) in CLE and WCE. Experiments with ≤1mm particle size constantly produced acidic and metal laden leachates. Co-disposal of FA and WRs as cover and mixture need to be investigated on pilot-scales before full-scale application.

Purpose of this work is show possibility of using grapichs cart for imaging a video signal. This work is particularly focused on technology CUDA and OpenCL. The solution is first focused on graphics cart and show how has been changed components and how has been changed performaces of graphics cart. Then show CUDA and OpenCL technology itself, and show samples of codes with explain, what which code do. Output of this work is some programs, witch defined for both technology and for both procesors unit. Contribution of this work is show differents between procesors unit, witch can be used to right choose for design your own algorithm.

4 mal im Jahr erscheinende Zeitschrift über aktuelle Themen der TU Chemnitz:Wer Wissen produziert, muß stärker gefördert werden Neuer Name für Alma mater Chemnitzer Uni ist das geistige Zentrum der gesamten Region FOCUS: TU Chemnitz - die beliebteste Uni in Deutschland Nachlaß an Universitätsarchiv übergeben Herzliches Wiedersehen nach über 70 Jahre Plenarversammlung des Philosophischen Fakultätentages Einblicke führten zu Einsichten Studiengebühren nun auch in Chemnitz Studentischer Börsenverein initiiert Aktionstag Börse Auf zu neuen Ufern Partnersuche im fernen Osten Interkontinentaler Brückenschlag Zu Gast bei den Soziologen Fähige Ingenieure und Physiker - händeringend gesucht Der kleinste Scheinwerfer der Welt Uni-Forscher sind Partner von neuem Fuzzy-Entwicklungszentrum Wettlauf ins Nanozeitalter Die feinen Unterschiede zwischen Ost und West Gestochen scharfe Fernsehbilder - Ein Traum wird wahr Damit Sorglosigkeit nicht länger zu Krankheiten führt Wohin mit dem Gummiabfall? Wiener Walzer der Rotoren unter flackerfreiem Licht Berge von Gips, doch der Markt ist zu Tips für Unternehmen auf CD und Video Die Wahrheit liegt irgendwo dazwischen Die faszinierende Schönheit der Toeplitzoperatoren Überraschung für den Guru der Schweißtechnik Chemnitzer Verbundwerkstoff-Forscher in Paris auf Erfolgskurs Messeteilnahmen im Herbst 1997 Die Philosophie des 19. Jahrhunderts neu beleuchtet Vor 300 Jahren: Wahl August des Starken zum König von Polen Erfolgsfaktor Marketing Treff der Umformer in Chemnitz Literatur Live Von Klavier bis Gesang Der Milchzug hielt im VOXXX Chemnitzer Historiker haben gut lachen Die Oper im Wandel der Zeit 5.000 Gulden durch Benefizkonzert für neue Orgel Von Zwickau über Tampere nach Rom Morts-Spaß an der Universität Chemnitzer Fechtsportler in Emden erfolgreich 2. Sächsische Schulsportkonferenz Herrscher über 16 Figuren: IM Womacka zeigt es allen Antje auf dem Sprung nach vorn Theatervorstellungen

Une des pathologies les plus répandues dans les pays développés est la dégénérescence maculaire liée à l’âge (DMLA). Elle se présente sous différentes formes dont la plus sévère est caractérisée par la présence de formation de néo-vascularisation provenant de la choroïde (CNV) migrant vers la rétine. Malheureusement, le diagnostic peut être seulement posé une fois que les symptômes apparaissent et que la vision est déjà affectée. Récemment, un vif engouement s’est porté sur les microARN (miARN), devenus des molécules d’intérêt pour le développement de biomarqueurs et représentant également un important potentiel thérapeutique. Nous avons donc émis l’hypothèse que l’identification de miRNA dans un contexte de DMLA avec CNV permettrait de caractériser leurs rôles, tant au niveau de l’identification de biomarqueurs que de nouvelles cibles thérapeutiques. Le premier objectif de notre projet était d’identifier chez l’humain une signature de miARN spécifique à la forme humide de la DMLA. Pour ce faire, nous avons réalisé un criblage des miARN dans l’humeur vitrée de patients. Nous avons observé une augmentation des niveaux de miR-146a et une diminution de miR-106b et miR-152 spécifique à la DMLA. Cette signature fut confirmée dans le plasma de cette même cohorte de patients. D’autre part, l’exploration de bases de données AMD Gene Consortium (AGC) et Ingenuity Pathway Analysis (IPA) a démontré une relation entre les miARN détectés et des mutations génétiques associées à la forme DMLA avec CNV. En effet, nous avons identifié un SNP (single-nucleotide polymorphism ou SNP) (rs1063320) dans un site de liaison de miR-152 du gène HLA-G. Le second objectif était d’explorer la possibilité d’utiliser, du point de vue thérapeutique, un des miARN identifiés au 1er objectif. Nous avons, tout d’abord, quantifié l’expression de miR-146a, miR-106b et miR152 dans un des modèles classiques de la DMLA avec CNV chez la souris (brûlures par laser). Le candidat retenu fut miR-106b, puisqu’en plus d’être impliqué dans l’angiogenèse, son expression dans le modèle animal reflétait de plus près celle obtenue chez les patients. Suite à ces résultats, nous avons: exploré A) le mécanisme influençant la diminution de l’expression de miR-106b et B) l’effet de sa surexpression sur l’angiogenèse. D’abord en A), nous avons observé une activation de la voie de PERK dans notre modèle animal de CNV induite par laser menant à une diminution de l’expression de MCM7 et du polycistron miR-106b~25. . Ensuite en B), nous avons pu observer l’effet anti-angiogénique de miR-106b sur la migration des cellules endothéliales in vitro et sur la formation de NV in vivo. L’action anti-angiogénique de miR-106b pourrait ainsi avoir un potentiel thérapeutique important sur la formation de la CNV dans la DMLA. / Age-related macular degeneration (AMD) is a leading cause of blindness worldwide affecting individuals over the age of 60. The neovascular form (NV AMD) is characterized by choroidal neovascularization (CNV) and is responsible for the majority of central vision impairment. Unfortunately, diagnostic of AMD can only be done after symptoms have appeared and loss of visual field occurred. Recently, there is a growing interest in microRNAs (miRNAs) for their eventual use in the development of new biomarkers or new therapeutic strategies. Our hypothesis is that wet AMD is associated with specific signature of several miRNAs that can be used as biomarkers for the disease. These miRNAs can be harnessed for therapeutic interventions. Our first objective was to identify a specific signature of miRNAs for wet AMD by using non-biased microRNA arrays and individual TaqMan qPCRs. We profiled miRNAs in the vitreous humour and plasma of patients with NV AMD. We identified a disease-associated increase in miR-146a and a decrease in miR-106b and miR-152 in the vitreous humour, which was reproducible in plasma. Moreover, miR-146a/miR-106b ratios discriminated patients with NV AMD with an area under the Receiver Operating Characteristic curve (ROC AUC) of 0,977 in vitreous humour and 0,915 in plasma, suggesting potential for a blood-based diagnostic. Furthermore, using the AGC and IPA database, we mapped a NV AMD-associated single nucleotide polymorphism (SNP) (rs1063320) in a binding site for miR-152-3p in the HLA-G gene. Our second objective was to explore the therapeutic potential of a specific miRNA (identified in objective 1). First, we explored the expression levels of miR-146a, miR-106b and miR-152 in the laser burn mouse model. We demonstrated that levels of miR-106b were significantly decreased in this mouse model of CNV. We divided this objective in two parts: Part A, explore mechanisms causing miR-106b downregulation and part B, study the therapeutic potential of miR-106b on the inhibition of angiogenesis and CNV formation. First, we showed that expression of the miR-106b-25 cluster is negatively regulated by the ER stress pathway of protein kinase RNA-like ER kinase (PERK) and a reduction in levels of MCM7, the host gene of miR-106b. �����Second, we demonstrated that therapeutic delivery of miR-106b to the retina with lentiviral vectors protects against aberrant retinal neovascularization in two distinct mouse models of pathological neo-vascularization. Results from this study suggest that miRNAs, such as miR-106b, have the potential to be used as multitarget therapeutics for conditions characterized by aberrant retinal neovascularization.

Impacts from mining waste deposits on groundwater resources have been recognized invarious parts of the world; though varied in scale depending on the composition of mineralsbeing mined, the level of technology employed and environmental commitment of thedevelopers. Mining activities usually involve milling, concentrating, and processing of oreswhich will result in a huge amount of waste, called tailings, usually deposited inimpoundments as a slurry, composed of fine grained geological material (uneconomicalminerals), chemicals utilized in the processs, and water. Oxidation of these deposits, usuallycontaining sulphide minerals, may result in generation of an acidic, metal laden leachate,callled Acid Mine Drainage (AMD), which may have a devastating impact on thesurrounding groundwater resources. In this study, the stochastic LaSAR-PHREEQC reactive transport modeling approach is usedin order to evaluate the coupled effect of geochemical reactions and physical heterogeneity ofthe subsurface in the breakthrough of acidity and metal downstream of the source while theAMD transported in the water saturated zone of an impoundment. The tailings depositcalled Impoundment 1 at the Kristineberg mining site at the Skellefteå field, in northernSweden, is used as a case study to simulate pH buffering processes and attenuation of Zn.The objectives of the study are 1) to evaluate the relevance of different possible geochemicalprocesses in pH buffering and Zn attenuation; 2) to evaluate the effect of spatial variability ofthe physical processes of the groundwater system on the breakthrough of contaminants; and3) to evaluate the effect of the location and distribution of the source zone in terms of thedistance from the impoundment boundary. Simulation results of the presented model revealed that pH buffering from calcite andchlorite are important processes capable of counteracting the acidification from AMD.Dissolution of secondary Al(OH)3(s) is another important process capable of buffering pH.Precipitation of smithsonite, ZnCO3, is an important process for attenuation of Zn2+.Moreover, sorption of Zn2+ on ferric iron surfaces is found to be an important process forattenuation of the metal, depending on the available sorption surface sites. Flow variabilityhighly affects the breakthrough of the contaminants such that with increasing subsurfaceheterogeneity, earlier breakthrough of contaminants occurs. Moreover, increased variabilityresults in decreased peak loads, but longer duration of the load. / www.ima.kth.se

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