Nanoparticles have gained growing attention of the scientific community over the past few decades due to their high potential to be used in diverse industrial applications. Nanoparticles often possess superior characteristics, such as catalytic activity, photochemical activity, and mechanical strength, compared to their bulk counterparts, making them more desirable in different industrial applications. During the past few decades, the use of the nanoparticles in various industries has been increased. With increasing usage release of nanoparticles into the environment has also increased. There is a growing concern about the nanoparticle toxicity and numerous studies have shown the toxic effects of different nanoparticles on various plants, animals, and microorganisms in the environment. Toxicity of nanoparticles is often attributed to their morphology and their ability to undergo different transformations in the environment. These transformations include aggregation, dissolution, and surface adsorption. Natural organic matter (NOM) are the most abundant natural ligands in the environment which include Humic acid and Fulvic acid. These high molecular weight organic molecules have complex structures and contain many different functional groups such as carboxylic acid groups, hydroxyl, amino and phenolic groups that can interact with the nanoparticle surface. The nature and the intensity of the interaction are dependent on several factors including the size and the surface functionality of nanoparticles and pH of the medium. The smaller the nanoparticle, the higher the adsorption of NOM due to the high surface to volume ratio of smaller particles. Functional groups on the surface dictate the surface charge of the nanoparticles in water depending on the acidity. The higher the acidity, higher the adsorption of NOM due to increased electrostatic attractions between positively charged nanoparticles and the negatively charged NOM molecules. Adsorbed NOM on nanoparticles affect the other transformations such as aggregation and dissolution and can in turn alter the reactivity and toxicity of the nanoparticles. Therefore, effect of NOM is an important factor that should be considered in environmental toxicity related studies of nanoparticles.

For bioactive chemical classes, it is often assumed that environmental transformation eliminates associated ecosystem risks. However, for endocrine-active steroid hormones, modest changes in structure can have a significant influence on biological activity and thus, subtle environmental transformations can yield products with conserved, enhanced, or activity across different biological endpoints. The aim of this work was to explore the environmental fate of high potency, endocrine-active steroid hormones during natural or engineered water processes in order to test the hypothesis that steroid transformation products generated during these processes are likely to contribute to residual bioactivity often reported in water resources. Specifically, laboratory experiments were used to simulate chemical disinfection (e.g., chlorination) or natural processes (e.g., photolysis) to: (i) determine the rate and extent of steroid transformation, (ii) isolate and identify products that are formed, and (iii) evaluate products or product mixtures for biological activity. These experimental results can be used to help guide occurrence studies for any products of concern in the environment and also guide computational predictions or rationalizations of chemical reactivity. Ultimately, the goal is to expand upon our awareness and understanding of how these potent endocrine ligands behave in the environment and how they potentially affect ecosystem health. Chapter 2 discusses the reaction of glucocorticoids (GC)s with aqueous chlorine (effectively, HOCl) to simulate their fate during engineered drinking water and wastewater chemical disinfection. Numerous transformation pathways were unveiled, including interconversion of GCs (e.g., endogenous cortisol to synthetic prednisolone), production of known androgens in the adrenosterone class, and chlorination of GCs (e.g., formation of 9-chloro-prednisone). We also showed that other advanced processes (e.g., oxidation via ozonation) result in more complete degradation of such pollutants, and may be better alternatives to chemical disinfection at eliminating bioactive steroidal product formation. In Chapter 3, results of the direct photolysis of dienogest (DNG), a widely prescribed oral contraceptive agent, are presented to simulate its fate in natural sunlit surface waters and engineered photochemical treatment systems (e.g., UV disinfection systems). The major products (~ 80% of the converted mass in neutral aqueous solutions) were identified to be photohydrates resulting from photochemical-induced incorporation of water into parent DNG. These products were found to be prone to dehydration in the dark, and thus, a source of substantial DNG regeneration (~ 65% after 72 h in neutral solutions). Other minor, non-revertible products were also identified, including two known estrogens. Although minor in initial yield, these estrogens are likely to accumulate over time through repeated cycling between DNG and its photohydrates, and thus, dominate DNG long-term fate. It was also found that DNG undergoes an unusual photochemical rearrangement to produce a minor product with a novel tetracyclic ring system--the subject of Chapter 4. Further, the generality of this unique photorearrangement process was explored through extension to the photolysis of two other dienone pharmaceutical steroids (e.g., the androgens methyldienolone and dienedione). Surprisingly, despite the significant change in core steroidal structure, the rearrangement products retain some progesterone receptor (PR) and androgen receptor (AR) bioactivity (i.e., low-µM to sub-nm EC50 values). Again, these represent other non-revertible, minor products that are likely to accumulate over time, with likely adverse ecological consequences. Chapter 5 covers results arising from the direct photolysis of trenbolone acetate (TBA) metabolites in the presence of model nucleophiles (e.g., sodium azide, sodium thiosulfate, ammonium hydroxide, hydroxylamine, and humic acid), some of which would be expected to be present, along with TBA metabolites, in agriculturally-impacted water resources. Previous studies by our group revealed that TBA metabolites undergo photohydration-thermal dehydration cycling, like that described above for DNG photolysis. The objective of this study was to determine if other nucleophiles would outcompete water for photochemical incorporation across the TBA metabolite extended conjugation system. It was found that TBA metabolite photolysis results in photochemical (and at times thermal) addition of the nucleophile to the TBA metabolites. It was also found that the addition products undergo thermal elimination in the dark and contribute to TBA metabolite regeneration, and therefore, are expected to increase TBA metabolite persistence in water resources. Finally, Chapter 6 discusses the reactions of various trienone and dienone steroids with aqueous chlorine to simulate their fate during engineered drinking water and wastewater chemical disinfection. Single-step transformation pathways were unveiled for each steroid class, including 4-chlorination (trienones) and 9,10-epoxidation (dienones). Chlorination at position C-4 is known to enhance anabolic potency of androgenic steroids and the 9,10-epoxy products were found to undergo acid- or base-catalyzed ring-opening and aromatization to yield known estrogenic products. In addition, Chapter 7 provides conclusions and future directions, while Chapter 8 details the experimental methods and procedures used throughout this thesis. Collectively, the results presented herein confirm our overall hypothesis that steroid transformation products would be expected to contribute to residual biological activity often detected in water resources. Furthermore, the results indicate that the transformation of high potency pharmaceuticals does not automatically equate with reduction or elimination of hazards to exposed organisms, especially in cases where such compounds have potential to form products exhibiting diverse biological endpoints. More holistic approaches to risk assessment of such high potency environmental contaminants are needed in order to accurately assess the fate and effects of such emerging pollutant classes and their bioactive transformation products.

En Allemagne, en Belgique, en France, en Irlande, en Islande, en Slovénie ou au Portugal, la gauche radicale connaît des poussées électorales, atteignant bien souvent des niveaux là aussi inédits. Dans les pays dans lesquels elle est traditionnellement bien implantée, si elle ne perce pas, elle demeure un acteur important de la vie politique et parlementaire, notamment à Chypre, en République tchèque, en Finlande, en Suède. Il est donc pertinent d’interroger le phénomène : pourquoi ce retour en force des partis de la gauche radicale ? Quelles en sont les causes ? Qui sont les acteurs partisans de ce renouveau ? Apporter des réponses à ces questions ne peut que passer par une analyse comparative.La thèse se fixe comme objectif de répondre à deux questions ayant structuré sa rédaction :1/ pourquoi la gauche radicale européenne se transforme-t-elle, quels sont les facteurs provoquant cette transformation en incitant ses dirigeants à l’opérer, et quelle est la nature de ces transformations ?2/ quels sont les objectifs et les attendus de ces transformations, et comment se traduisent-elles par le ralliement de nouveaux électeurs dans le cadre des échéances électorales ?Nous partons en effet du principe qu’un parti ne se transforme pas en vain. S’il amende son identité, son projet, ses discours ou le mode de fonctionnement de son organisation, c’est qu’il escompte franchir un cap dans son développement. Au travers d'une analyse comparative entre l'Allemagne, l'Espagne, la Grèce et le Portugal, nous verrons qu'émerge et se structure une nouvelle gauche radicale impactant durablement la famille partisane de la gauche radicale européenne. / In Germany, Belgium, France, Ireland, Iceland, Slovenia and Portugal, radical left parties are experiencing electoral surges, often reaching new levels as well. In countries where they are traditionally well established, if they don't break through, they remain an important player in political and parliamentary life, particularly in Cyprus, Czech Republic, Finland and Sweden. It is therefore relevant to question the phenomenon: why this return in force of the radical left parties? What are the causes? Who are the actors in favor of this renewal? Answering these questions can only be done through a comparative analysis.The thesis aims to answer two questions that have structured its writing:1 / why is the european radical left transforming itself, what are the factors causing this transformation by encouraging its leaders to operate it, and what is the nature of these transformations?2 / What are the objectives and expectations of these transformations, and how do they translate into the rallying of new voters in the elections?We start from the premise that a party does not change in vain. If a prty amends its identity, its project, its speeches or the mode of operation of its organization, it is that this party expect to cross a course in its development. Through a comparative analysis between Germany, Spain, Greece and Portugal, we will see the emergence and structuring of a new radical left permanently impacting the partisan family of the European radical left.

In pattern recognition applications, it is usually important that the same identification be given for a pattern, independent of a variety of positions, rotations and /or distortions of the pattern within the recognition device's field of view. This research relates to development of a preprocessor for a neural network character recognition system, where the role of the preprocessor is to assist in minimizing the difficulties related to variations of position and rotations of a character within the field of view. The preprocessor explored here was suggested in 1970' (Lendaris & Stanly, 1970), and is implemented here with more recent advances in neural network and discrete computation technologies. The preprocessor consists of calculating the two-dimensional Fourier transform of the image (current hardware technology allows this to occur in less than 100 ms for a 256x256 pixels image , on a PC based machine with accelerator card), and then taking certain measurements on the transformed image. These measurements are given to the neural network, which processes the data to provide the character identification. Introduction of the preprocessor is shown to yield a great reduction in sensitivity to image translation and/or rotation.

With the advance of the VLSI technology, the FFT algorithm has been pushed further in solving the multidimensional array signal processing in real time. Many DSP chip users have tried to find ways to improve addressing huge data in multidimension systems with minimum cost and maximum performance. However, there is no efficient method to address data for 1-D to M-D FFTs. A methodology has been defined to conquer the addressing problem ofM-D FFT. It is well known that the twiddle factor matrix of Discrete Fourier Transform (DFT) can be recursively factored into basic butterfly stage matrices. The matrix can be factored into three matrices practically specifying the input data, twiddle factor, and output data sequence of the Fast Fourier Transform (FFT). The equivalent relationship of these matrices will be introduced. The equivalent relationship for a variety of the FFT algorithms can be obtained by equivalent transformations. Furthermore, the multidimensional (M-D) FFT can be represented by the same vector-matrix form as the one-dimensional (1-D) FFT. In addition, the addressing sequences of the 1-D FFT is a subset of the M-D FFT. Therefore, the signal flow graph of the 1-D FFT can be used to describe that of the M-D FFT and all M-D indexing can be implemented by 1-D indexing. Finally, this unified indexing approach was implemented into the WinDSP software simulator. Examples of M-D FFTs implemented with the unified indexing method are simulated on the WinDSP and the computation performance were analyzed. From the benchmark analysis, the 2-D FFT applications implemented with unified methodology use less instructions and the execution time is almost two times faster than the traditional method. WinDSP is a software simulator that simulates the functional characteristics of Sharp LH9124/LH9320 DSP chip set. It intended to manage the complete development of DSP applications, from conceptualization and experimentation, to verification of unified indexing for 1-D to M-D FFT. It is also intended for system development, where hardware can be implemented for the design.

A Thermal Energy Storage (TES) system is meant for holding thermal energy in the form of hot or cold materials for later utilization. A TES system is an important technological system in providing energy savings as well as efficient and optimum energy use. The main types of a TES system are sensible heat and latent heat. A latent heat storage is a very efficient method for storing or releasing thermal energy due to its high energy storage density at constant temperatures, and a latent heat storage material can store 5-14 times more heat per unit volume than a sensible heat storage material can. Phase Change Materials (PCMs) are called latent heat storage materials. PCMs can save thermal energy, and use energy efficiently because PCMs can absorb thermal energy in the solid state, and the thermal energy can be released in the liquid state. Therefore, PCMs as new materials for saving energy can be applied into building applications. PCMs have been widely researched, but the current issues are lack of accurate and detailed information about thermophysical properties of PCMs to apply to buildings and inaccurate materials properties measured by existing methodology. The objective of this study is to develop a methodology and procedure to accurately determine the thermophysical properties of PCMs based on salt hydrates. TES systems of PCMs are measured and analyzed by various methods, such as DSC method and heat flow method. In addition, this study demonstrates to design a building roof with PCMs to save energy using Finite Element Analysis (FEA). The developed methodology is designed based on ASTM C1784-14, Standard Test Method for Using a Heat Flow Meter Apparatus for Measuring Thermal Storage Properties of Phase Change Materials and Products, for measuring the thermal energy storage properties of PCMs. The thermophysical properties and thermal stabilities are evaluated by using a Differential Scanning Calorimetry (DSC), which is made with DSC Q 200 equipment from TA Instruments and DSC STA 8000 equipment from Perkin Elmer Company. The thermal conductivities are assessed by heat flow meter, which is FOX 314 equipment from TA Instruments, and the enthalpy changes of the PCMs are determined by DSC method and heat flow method. Numerical FEA to evaluate potential energy savings is conducted using ABAQUS software. Four types of Phase Change Materials (PCMs), which have phase changes at 21ºC, 23ºC, 26ºC, and 30ºC, respectively, are used for measuring the thermophysical properties. The onset/peak temperature, the enthalpy, the heat flow, and the heat capacity of the PCMs are measured to assess the thermal energy storage system under the dynamic DSC mode. The results obtained using DSC equipment have a higher melting temperature than their own temperatures, which are known theoretically. The freezing temperatures of the PCMs are decreased by about 30ºC ~ 40ºC compare to their theoretical freezing temperatures. It is speculated that supercooling happens during the solidification. The enthalpy change curves as a function of temperature, which are determined by DSC method and heat flow method, are indicated to assess thermal energy storage system of the PCMs. During the phase change, the energy is increased. This is the reason why the energy is utilized to loosen or break apart the molecular or atomic bond structures of the PCMs by the latent heat. Moreover, the enthalpy change curves determined by heat flow method show more precise results than the curves by DSC method, because various factors lead to a temperature gradient in the PCM and the heat flux signal peak being shifted toward high temperatures. Regarding the thermal conductivities results of the PCMs, the thermal conductivities of the PCMs in the solid state are higher than those of the PCMs in the liquid state. This phenomenon happens due to the effect of the microstructure changing from the orderly solid structure in the solid state to the disorderly liquid structure in the liquid state. The numerical Finite Element Analysis (FEA) is conducted to evaluate potential energy savings of a roof. The results, such as the temperature variations from the outdoor to indoor measured under step 1 (the daytime) condition, show that the outdoor temperatures are higher than the indoor temperatures. This is due to the low thermal conductivity of the PCM in the liquid state. The low thermal conductivity of the PCM reduces the heat transmission to the indoor that in turn increases the outdoor temperature. This study shows the developed methodology and procedure, the accurate material information for the newly developed PCM, and the numerical FEA to analyze the TES systems with much more precision in the area of the PCMs.

nitrogen has commonly been a deficient element in the cultivated soils of the world since the beginning of agriculture. The general acceptance of the practice of using manures as a means of increasing plant growth, as shown by the records of ancient civilizations, attest to this fact. Since the time of von Liebig there has been an increasing awareness of the importance of this deficiency in soils. As a result of a better understanding of the problem and the increasing availability of commercial forms of nitrogen, a rapid increase in the use of nitrogen fertilizers has taken place in the last few decades. this increasing use of commercial forms of nitrogen is accompanied by the need for more information concerning the proper use of these materials in order to accomplish the greatest benefit. For example, with the advent of increasing use of ammonium fertilizer to improve soil productivity, there has arisen a possibility of lengthening the period from the date of the fertilizer application to the time of utilization by the crop. this advanced application, especially in the fall of the year, has many advantages and is widely advocated. The following questions need to be answered in connection with efficiency of such a practice: Will the ammonium form of nitrogen remain unoxidized in the soil over the winter months? Could it be only partially oxidized and result in an accumulation of nitrites that may cause toxicity or be lost from the soil in gaseous forms such as nitrous oxide? What are the chance for significant losses by volatilization before it is oxidized? How does the amount of moisture and the prevailing temperature affect these transformations? The study reported here is an endeavor to contribute to more complete answers to some of these questions. Although much research has been conducted relating to the effects of moisture or temperature on nitrogen transformations in the soil, more information is needed covering greater variations in the moisture and temperature levels along with the interactions of these. Accordingly, experiments were conducted under carefully controlled conditions to measure the changes occurring in the inorganic soil nitrogen from an applied ammonium source, at various moisture and temperature levels.

We present a new spectral problem, a generalization of the D-Kaup-Newell spectral problem, associated with the Lie algebra sl(2,R). Zero curvature equations furnish the soliton hierarchy. The trace identity produces the Hamiltonian structure for the hierarchy. Lastly, a reduction of the spectral problem is shown to have a different soliton hierarchy with a bi-Hamiltonian structure. The first major motivation of this dissertation is to present spectral problems that generate two soliton hierarchies with infinitely many commuting conservation laws and high-order symmetries, i.e., they are Liouville integrable. We use the soliton hierarchies and a non-seimisimple matrix loop Lie algebra in order to construct integrable couplings. An enlarged spectral problem is presented starting from a generalization of the D-Kaup-Newell spectral problem. Then the enlarged zero curvature equations are solved from a series of Lax pairs producing the desired integrable couplings. A reduction is made of the original enlarged spectral problem generating a second integrable coupling system. Next, we discuss how to compute bilinear forms that are symmetric, ad-invariant, and non-degenerate on the given non-semisimple matrix Lie algebra to employ the variational identity. The variational identity is applied to the original integrable couplings of a generalized D-Kaup-Newell soliton hierarchy to furnish its Hamiltonian structures. Then we apply the variational identity to the reduced integrable couplings. The reduced coupling system has a bi-Hamiltonian structure. Both integrable coupling systems retain the properties of infinitely many commuting high-order symmetries and conserved densities of their original subsystems and, again, are Liouville integrable. In order to find solutions to a generalized D-Kaup-Newell integrable coupling system, a theory of Darboux transformations on integrable couplings is formulated. The theory pertains to a spectral problem where the spectral matrix is a polynomial in lambda of any order. An application to a generalized D-Kaup-Newell integrable couplings system is worked out, along with an explicit formula for the associated Bäcklund transformation. Precise one-soliton-like solutions are given for the m-th order generalized D-Kaup-Newell integrable coupling system.

Orientador: Rawlilson de Oliveira Araújo / Resumo: O presente trabalho trata das semelhanças de segmentos e figuras geométricas, em especial o triângulo. Iremos demonstrar alguns teoremas "famosos" utilizados na resolução de problemas que envolvem semelhanças, e outros que são desconhecidos para os jovens do ensino básico tais como Teorema de Ceva, Triângulo medial e a linha de Euler e Triângulos Pedal mas que têm a sua importância na matemática. / Abstract: The present work deals with the similarities of segments and geometric figures, especially the triangle. We will demonstrate some "famous" theorems used to solve problems involving similarities, and others that are unknown to the youngsters of elementary education such as Ceva Theorem, Medial Triangle and Euler aligns and Pedal Triangles but which have their importance in mathematics. / Mestre

<p>Les modèles de systèmes de contrôle en dimension finie et en temps continu sont les équations différentielles ordinaires sous-déterminées, c'est-à-dire prescrivant l'évolution d'une partie des variables alors que d'autres, les contrôles, sont libres. Cette sous-détermination fait que la classe de transformations possibles est très variée et que le problème est par exemple très différent de celui des systèmes dynamiques classiques (sans contrôle, ou équations différentielles ordinaires déterminées). On a fait, dans le chapitre 1 (le seul original) un effort de clarification des différents types de transformations (statiques, dynamiques, fonctionnelles..) en les énonçant en terme de correspondances entre <u>solutions</u>; on présente ensuite des contributions des dernières années, concernant des conditions géométriques d'équivalence ou de linéarisation, et des problèmes encore ouverts; les détails sont contenus dans huit articles publiés reproduits dans le mémoire aux chapitres suivants (en anglais) avec seulement quelques modifications de référencement. </p><p> Étudier la structure des transformations sur les modèles, leur équivalence, leur classification a deux motivations distinctes: <br>- pour concevoir un contrôleur à partir d'un modèle donné du système, on a souvent intérêt à analyser, comprendre, simplifier ce modèle, <br>- le choix d'un modèle demande une compréhension de la structure de la classe des modèles non-linéaires (par exemple: quand deux modèles traduisent-ils la même réalité?). La modélisation ou l'identification non-linéaires sont encore des champs en friche qui manquent de fondements conceptuels.</p>