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L’objectif de ce mémoire est de quantifier la diagenèse de l’arsenic (As) dans les sédiments, d'utiliser ceux-ci comme archive environnementale et d’identifier les réactions clés de l’As. Huit lacs ont été visités en juin 2018 et mai 2019, le long d’un transect de 80 km au nord-ouest de la mine d’or Giant, à Yellowknife, dans les Territoires du Nord-Ouest, Canada, pour y prélever de l’eau de surface, des carottes de sédiments et de l’eau porale. Ces échantillons ont été analysés afin d’obtenir les concentrations dissoutes et solides de carbone organique, d’As, de fer (Fe), manganèse (Mn) et d'aluminium (Al) et des anions nitrate, sulfate, sulfure et chlorures. Les concentrations d’As dans l’eau porales ont été interprété à l’aide de la modélisation diagenétique inverse et de calculs thermodynamiques. L'historique des flux d’As solide déposés au fond des lacs a été calculé après correction pour l'influence de la diagenèse. Les flux diffusifs d’As à l’interface eau-sédiment en réponse à la contamination causée par l’activité minière ont été calculés pour les deux années d'échantillonnage. Les résultats montrent que la diagenèse est plus importante dans les lacs avec des taux de sédimentation plus faibles. Après correction, les données indiquent que les flux d'As maximaux coïncident avec la période d'activité de la mine. Néanmoins, les lacs près de la mine sont toujours sous l’influence d’apports importants d’As dissous depuis leur bassin versant, et montrent des flux diffusifs élevés d’As vers la colonne d’eau. Les calculs thermodynamiques de spéciation et des indices de saturations suggèrent que la mobilité de l'As est liée à celle des oxydes de fer et au soufre. Le sulfure de fer amorphe se forme dans les sédiments et l’As co-précipite ou s’adsorbe sur cette phase minérale. Enfin, le moment de la fonte du couvert de glace, qui permet l’arrivée de l’oxygène, semble déterminer la mobilité de l’As auprintemps. Dans le contexte où les changements climatiques influencent la durée du couvert de glace, une étude approfondie de l’effet du couvert de glace sur les conditions d’oxydoréduction est souhaitable. / The goal of this thesis is to quantify the diagenesis of arsenic (As) in the sediments, using them as environmental archives and identify the key reactions of As. Eight lakes have been visited in June 2018 and May 2019, along an 80 km transect northwest from the gold mine Giant, near Yellowknife in the Northwest Territories, Canada to collect surface water, sediment cores and porewater. These samples have been analyzed to obtain the dissolved and solid concentration of organic carbon, As, iron (Fe), manganese (Mn) and aluminium (Al) and anions (nitrate, sulfate, sulfide and chloride). As concentrations in porewater were interpreted using inverse diagenetic modeling and thermodynamics calculations. The history of the fluxes of solid As deposited at the bottom of the lakes was calculated after correction for the influence of diagenesis. Diffusive fluxes of As at the sediment-water interface in response to contamination from mining activity were calculated for the two years of sampling. The results show that diagenesis is greater in lakes with lower sedimentation rates. After correction, the data indicates that the maximum As fluxes coincide with the period of mine activity. Nonetheless, lakes near the mine are still influenced by large inputs of dissolved As from their watersheds, and show high diffusive fluxes of As to the water column. Thermodynamic calculations of speciation and saturation index suggest that the mobility of Asis related to that of iron oxides and sulfur. Amorphous iron sulfide forms in the sediment and As coprecipitates or adsorbs to this mineral phase. Finally, the timing of the melting of the ice cover, which allows the arrival of oxygen, seems to determine the mobility of As in the spring. In the context of climate change shortening the duration of ice cover, an in-depth study of the effect of ice cover on redox conditions is desirable.

Appropriate conservation decisions and efforts must be based on real−time and accurate information about wildlife populations. However, it is extremely challenging to monitor the population demography and physiological traits of many threatened and secretive animal species through direct observation and capture. Near infrared spectroscopy (NIRS) has the potential to be a remote tool to address questions concerning wildlife physiology and demography by analyzing “signs” of animals without seeing or capturing them. In this dissertation, two species, the giant panda (Ailuropoda melanoleuca) and red panda (Ailurus fulgens) are used as a case study, to demonstrate NIRS’ feasibility in studying their physiological properties. The aim of this study is to test NIRS’ potential as a real−time analytical tool for in the nutritional foodscape and demographic analysis using less processed or non−processed field fecal and forage samples with the help of the mode−cloning technique to transfer the master model (dry and ground samples) under laboratory conditions to satellite modes (wet or dry but unground) in field conditions. Mode−cloning is conducted using either slope and bias correction (SBC) or two spectral correction methods, piecewise direct standardization (PDS) and external parameter orthogonalization (EPO). The following four hypotheses are tested this dissertation: (1) by using mode−cloning with both SBC and PDS, unprocessed wet or unground dry bamboo leaves (pandas’ food) can be used to determine the crude protein contents; (2) machine learning−based classification models using less processed field feces after mode−cloning with spectral correction approaches (PDS and EPO) can differentiate between sexes of the giant panda; (3) mode−cloned machine learning classification models using field feces can detect pregnancy of female giant pandas; (4) with the application of mode−cloning, field fecal samples can provide sex differentiation of the red panda. This dissertation demonstrates that NIRS coupled with mode−cloning and machine learning has the potential to provide real−time and accurate prediction to determine bamboo foodscape quality and reproductive status of the giant panda and red panda using minimally processed biological samples, thus allowing quick decision-making for both in situ population monitoring of these two species and ex situ husbandry preparations for pregnant female giant pandas.

Astrophysical phenomena such as self-annihilation of primordial black holes (PBHs), gamma ray bursts (GRBs), and supernovae are expected to produce single dispersed pulses detectable in the low end of the radio spectrum. Analysis of these pulses could provide valuable information about the sources, and the surrounding and intervening medium. The Eight-meter-wavelength Transient Array (ETA) is a radio telescope dedicated to the search for these pulses in an 18 MHz bandwidth centered at 38 MHz. ETA consists of 10 dual-polarized active dipoles providing an all-sky field of view. This thesis describes the results of a search campaign using ETA, namely, a Crab giant pulse (CGP) search. CGPs are already known to exist, and thus provide an excellent diagnostic for system performance. We found 11 CGP candidates in 14 hours of data. Although there has not been a single compelling detection (signal-to-noise ratio > 6), our analysis shows that at least a few of these candidates may be CGPs. We also explain the analysis preparation for PBH and GRB searches. Additionally, we describe the instrument and a software "toolchain" developed for the analysis of data that includes calibration, radio frequency interference (RFI) mitigation, and incoherent dedispersion. A dispersed pulse simulation code was developed and used to test the toolchain. Finally, improvements are suggested. / Master of Science

This thesis describes efforts to improve the realism of numerical models of giant planet formation and migration in an attempt to better understand these processes. A new approach has been taken to the modelling of accretion, designed to mimic reality by allowing gas to accumulate upon a protoplanetary surface. Implementing this treatment in three-dimensional self-gravity radiation hydrodynamics calculations provides an excellent model for planet growth, allowing an exploration of the factors that affect accretion. Moreover, these calculations have also been extended to investigate the migration of protoplanets through their parent discs as they grow. When focusing on the growth of non-migrating protoplanets, the models are performed using small sections of disc, enabling excellent resolution right down to the core; gas structures and flow can be resolved on scales from ~ 10^4 to 10^11 metres. Using radiative transfer, these models reveal the importance of opacity in determining the accretion rates. For the low mass protoplanets, equivalent in mass to a giant planet core (~ 10 M⊕), the accretion rates were found to increase by up to an order of magnitude for a factor of 100 reduction in the grain opacity of the parent circumstellar disc. However, even these low opacities lead to growth rates that are an order of magnitude slower than those obtained in locally-isothermal conditions. For high mass protoplanets (>~ 100M⊕), the accretion rates show very little dependence upon opacity. Nevertheless, the rates obtained using radiative transfer are still lower than those obtained in locally-isothermal models by a factor of ~2, due to the release of accretion energy as heat. Only high mass protoplanets are found to be capable of developing circumplanetary discs, and this ability is dependent upon the opacity, as are the scaleheights of such discs. However, their radial extents were found to be independent of the opacity and the protoplanet mass, all reaching ≈ RH/3, inline with analytic predictions. Migration is investigated using global models, ensuring a self-consistently evolved disc. Using locally-isothermal calculations, it was found that the capture radius of an accreting sink particle, used to model a protoplanet without a surface, must be small (<< RH) to yield migration timescales consistent with linear theory of Type I migration. In the low mass regime of Type I migration, accreting sinks with such small radii yield timescales consistent with those models in which a protoplanetary surface is used. However, for high mass protoplanets, undergoing Type II migration, the surface treatment leads to faster rates of migration, indicating the importance of a realistic accretion model. Using radiative transfer, with high opacities, leads to a factor of ~ 3 increase in the migration timescale of the lowest mass protoplanets, improving their chances of survival. As suitable gas giant progenitors, their survival is key to understanding the growth of giant planets. An unexpected result of the radiative transfer was a reduction in the migration timescale of high mass planets. This appears to be a result of the less thoroughly evacuated gaps created by planets in non-locally-isothermal discs, which affects the corotation torque.

This master thesis is about Elliptic Curve Digital Signature Algorithm or ECDSA and two of the known attacks on this security system. The purpose of this thesis is to find points that are likely to be points of high order on an elliptic curve. If we have a point P of high order and if Q = mP, then we have a large set of possible values of m. Therefore it is hard to solve the Elliptic Curve Discrete Logarithm Problem or ECDLP. We have investigated on the time of finding the solution of ECDLP for a certain amount of elliptic curves based on the order of the point which is used to create the digital signatures by those elliptic curves. Method: Algebraic Structure of elliptic curves over finite fields and Discrete logarithms. This has been done by two types of attacks namely Baby Step, Giant Step and Pollard’s Rho and all of the programming parts has been done by means of Mathematica. Conclusion: We have come into a conclusion of having the probable good points which are the points of high order on elliptic curves through the mentioned attacks in which solving the ECDLP is harder if these points have been used in generating the digital signature. These probable good points can be estimated by means of a function we have come up with. The input of this function is the order of the point and the output is the time of finding the answer of ECDLP.

Dans la tuberculose, Mycobacterium tuberculosis forme des granulomes dans les poumons avec, au centre, des cellules myéloïdes mono et multi-nucléées et autour, des lymphocytes. Nous avons étudié la biologie des cellules géantes dans ces granulomes tuberculeux : formation, mécanismes de survie et fonctions. Notre groupe a publié que l’IL-17A déclenche la fusion des cellules dendritiques (DC). Notre travail démontre que cette cytokine induit BCL2A1/BFL1, qui régule la survie des DC et les chémokines CCL2 et CCL20 qui dirigent le regroupement nécessaire à leur fusion. In situ, l'IL-17A est exprimée par les lymphocytes T de la couronne du granulome tuberculeux. BCL2A1, CCL2 et CCL20 sont exprimés par les cellules myéloïdes mono-et multi-nucléées. Ensuite, nous avons caractérisé le phénotype, les fonctions immunitaires et l'activité microbicide des DC traitées par l'IL-17A. Nous avons trouvé qu’elles co-expriment des marqueurs de DC et de macrophages, conservent les fonctions classiques des DC, synthétisent un profil spécifique d’enzymes destructrices et exercent une microbicidie variable suivant les souches de Mycobactéries. Nous avons nommé GMIC (Giant Myeloid Inflammatory Cell), ces cellules géantes induites par l'IL-17A. Nous proposons qu'elles constituent un nouvel effecteur myéloïde qui contrôle les mycobactéries. Ainsi, l'IL-17A participerait au maintien du cœur myéloïde du granulome tuberculeux en favorisant la formation des cellules géantes possédant des fonctions destructrices et microbicides. Les mécanismes moléculaires que nous avons documentés devraient permettre le développement de nouvelles stratégies thérapeutiques et vaccinales contre la tuberculose. / Tuberculosis, caused by Mycobacterium tuberculosis infection, results in the development of granulomas in affected tissues. These structures are formed by a myeloid cell core including multinucleated giant cells and surrounded by T lymphocytes. We studied mechanisms of survival, formation and functions of giant cells in Mycobacterium granulomas. Previously, our group showed that the cytokine IL-17A induces the fusion of dendritic cells (DC). Here, we identified molecules induced by the IL-17A genetic program in myeloid cells: BFL1 regulated DC survival, while the chemokines CCL2 and CCL20 directed clustering required for DC fusion. In situ, in human TB granulomas, we found that IL-17A was expressed by T lymphocytes while BFL1, CCL2 and CCL20 were expressed by the mono- and multi-nucleated myeloid cells. Then we characterized phenotype, immune functions and microbicidal activity of IL-17A-treated DC and their derived giant cells. They expressed a mixed DC-macrophage phenotype, retained classical DC functions, synthesized several destructive enzymes and had increased and differential microbicidal activities against Mycobacterium species. We named GMIC (giant myeloid inflammatory cells) these IL-17A-dependent giant cells, and propose that they constitute a new inflammatory myeloid effector with potent microbicidal activities. Altogether, our results show that IL-17A may participate in the maintenance of the myeloid core of human tuberculosis granuloma by promoting the formation of GMIC with potent destructive and microbicidal functions. The molecular mechanisms we have documented should help the development of new tuberculosis therapeutic and vaccination strategies.

The aim of this thesis is to compare similar cosmogonic narratives in Indian and Chinese culture. The most important elements are the motives of the egg and the giant/god who is formed from it. Comparative method consist of the comparison of the meanings and interpretations of the motives of these two elements, depending on the expectations and character of the source of this mythological narrative. Final findings are, that the importance of both motives in the texts and their participation in the process of creation of the world change chronologically, due to changes in religious, philosophical and social preferences. In Indian cultural environment in the begining, the vague motive of the egg slowly emerges and becomes a single creative element, gaining importance and continues to the stage where it reaches the same level of importance as the cosmic being. The primordial being on the other hand, loses its function of cosmic matter and passes it to the egg. The being itself then plays an active role rather than an object. China, for its religious scepticism suppressed motive of the egg until it was completely removed from texts. The primary role is played by the cosmic giant whose role is not focused on the creation of the world itself but the desintegration of the giants body, representing fission...

This thesis The Comparison of the Traditional Material Transport in the Mountain Economy of the Krkonoše and Šumava Mountains introduces the traditional forms of material and goods transport in the Krkonoše Mountains (the Giant Mountains) and the Šumava Mountains (the Bohemian Forest). The way of life in the highland area of Giant Mountains was significantly affected by the Alpine colonization in the second half of the 16th century. The Alpine colonists brought knowledge of logging, mountain economy and transport equipment into the mountains. Inhabitants of the Giant Mountains used water power, skids, later sledge called "rohacky" for bundles of wood. They also used backpacks, textile "loktuse", baskets, wheeled means of transportation and animal skid for the transport of other goods and materials. The comparison shows that the Bohemian Forest unlike the Giant Mountains was populated by gradual colonization of woodmen from the surrounding regions. Various forms of traditional vehicles were applied in this area. Unlike the Giant Mountains there was increasingly developed timber transport on the canals and rivers. The thesis maps the traditional modes of material transport in both regions, highlightes their differences and records their transformation in the present. Powered by TCPDF (www.tcpdf.org)

For a long time studies were focused on searching optimal conditions of germination of individual species. During the last few years studies have started to search for a relationship between germination and various species characteristics. Most of them, however, use only one temperature during germination tests. Very few studies use more than one temperature during the germination tests. In the last years studies started also to compare germination between rare and common species, but these studies compare just a few species. There are no studies which would compare germination on broader range of species. Aim of this study was to indentify which factors are determing germination of species and to find relationships between germination and characteristics of rare species (n=62). Another aim was to find out differences in germination of pairs (n=24) of closely related rare and common species. To test the germination I have chosen a methodology with several consecutive temperatures. Throughout the time of testing , the seeds were placed either in light or in dark. The dataset was processed by linear regression. The results show that germination requirements of species are determinet by time of flowering, weight of seeds, dispersal mode, species requirements for soil humidity and nutrients and type of...