Doctorat en philosophie et lettres / info:eu-repo/semantics/nonPublished

This study investigated the effects of grade level and gender on elementary school students&rsquo / motivation towards science learning. This study was carried out during 2007-2008 fall semester at 12 public elementary schools in Yenimahalle districts of Ankara. A total of 2231 students (1121 boys, 1093 girls, 17 did not report their gender) participated in the study. In terms of grade level, 1164 were enrolled in 6th grade level and 1055 in 8th grade (12 did not report their grade level). Data were collected through Students&rsquo / Motivation Towards Science Learning Questionnaire (SMTSL). Two-way Multivariate Analysis of Variance (MANOVA) was conducted in order to identify the effects of grade level and gender on six dimensions of motivation (i.e. self efficacy, active learning strategies, learning environment stimulation, science learning value, achievement goal and performance goal) towards science learning. Two-way MANOVA results showed that grade level and gender had a significant effect on the collective dependent variables. Follow-up univariate analysis indicated that there was a significant difference between 6th and 8th grade students&rsquo / motivation towards science learning regarding mean scores on each motivational variable. In addition, mean scores on each motivational variable, except leaning environment stimulation, were significantly different for boys and girls, in favors of girls. Result demonstrated that students&rsquo / motivation towards science learning declined as the grade level increased and girls had a higher motivation towards science learning than boys.

Orientador: Jean Marcel Carvalho França / Banca: Ronald José Raminelli / Banca: Denise Aparecida Soares de Moura / Resumo: Apesar da parca documentação, é notável, no século XVI, o afluxo de franceses em terras americanas os quais partindo, principalmente, das regiões da Normandia e da Bretanha chegaram ao litoral norte ou navegavam rumo às terras do sul, onde poderiam carregar as suas embarcações com peles, pau-brasil, papagaios, macacos e outros animais exóticos bastante apreciados na França, bem como na Europa. Um prova da assiduidade desses navegadores é a festa brasileira em Rouen, organizada em 1550 para homenagear o novo monarca francês, Henrique II, e a sua esposa, Catarina de Médici. Rouen destacou-se entre as outras cidades que receberam o casal real, oferecendo um espetáculo que até então não havia sido assistido na Europa: o cotidiano dos nativos do Novo Mundo. Cinco anos após esse episódio curioso em Rouen, uma expedição deixa o porto de Le Havre com o claro objetivo de construir um estabelecimento francês no Brasil e comandado por Nicolas Durand de Villegagnon. Na Baía de Guanabara, os franceses, huguenotes e católicos, entraram em contato com indígenas tupinambás de quem conseguiram grande parte dos alimentos para sobreviverem na França Antártica. Mas, o estabelecimento não durou muito tempo, pois Portugal decide tomar conta de seu território expulsando os franceses em 1560, além dos conflitos políticos-religiosos que perturbavam a própria França. Não demorou muito e em 1562, Jean Ribaut navega para a Flórida, numa viagem de reconhecimento, para instalação de uma futura colônia na região. Mais uma vez a sorte não estava do lado dos franceses. Na falta de víveres e de comunicação com a metrópole, os conflitos internos começam a aparecer até que, em 1565, Filipe II, da Espanha, ordenou uma expedição, comandada por Pedro Menéndez de Avilés, para acabar com a ousadia francesa. Apesar do fracasso nas tentativas de colonização, alguns ... (Resumo completo, clicar acesso eletrônico abaixo) / Résumé: Malgré la faible documentation, est remarquable au XVIème siècle, l'afflux des français dans les terres américaines qui, partant surtout, des régions de Normandie et de Bretagne sont arrivés au litoral nord ou ont navigué vers les terres du sud, où ils pourraient charger leurs embarcations avec des peaux, "pau-brasil", perroquets, singes et d'autres animaux exotiques aussi bien appréciés en France qu'en Europe. Une preuve de l'assiduité de ces navigateurs est la fête brésilienne à Rouen, organisée en 1550 en commémoration au nouveau monarque français, Henri II et à son épouse Catherine de Médici. Pour se distinguer parmi les autres villes qui ont reçu le couple royal, Rouen a offert un spectacle qui, jusqu'alors n'avait pas été assité en Europe: le quotidien des natifs du Nouveau Monde. Cinq ans après cet épisode curieux à Rouen, une expédition laisse le port du Havre avec le clair objectif de construire un établissement français au Brésil comandé par Nicolas Durand de Villegagnon. Dans la Baie de Guanabara, les français huguenots et catholiques sont entrés en contact avec des indigènes tupinambás de qui ils ont obtenu une grande partie des aliments pour survivre en France Antarctique. Mais l'établissement n'a pas duré longtemps parce que Portugal a decidé de prendre en charge son territoire, en expulsant les français en 1560, sans compter les conflits politiques-religièuse qui perturbaient la prope France. Peu de temps après, en 1562, Jean Ribaut voyage en Floride dans un voyage de reconnaissance pour l'instalation d'une future colonie dans la région. Mais, encore une fois le sort n'etait pas du côté des français, le manque de vivres et de communication avec la métropole, les conflits internes commencent à apparaître jusqu'à ce que, en 1565, Philippe II d'Espagne, a ordonné une expédition, commandée par Pedro Menéndez de ... (Résumé complete accés électronique ci-dessous) / Mestre

Memoria (licenciado en ciencias jurídicas y sociales)

Doctorat en philosophie et lettres / info:eu-repo/semantics/nonPublished

This dissertation explores Moderata Fonte’s Tredici canti del Floridoro from a new critical perspective, by taking into consideration Fonte’s authorial positionality, situating the text within its literary and historical contexts, and devoting sustained attention to its extradiegetic and structural components. Through this framing, this study highlights Fonte’s innovation as an author of chivalric epic and reveals the Floridoro to be a text with political motivations. The first chapter examines Fonte’s authorial persona and her metapoetics, both as they are written about by her contemporaries and as they are made manifest within the Floridoro. The remaining two chapters are devoted to an analysis of the two ekphrastic sub-narratives found within the Floridoro, and how they mirror Fonte’s dual dedication of the poem to Francesco I de’ Medici and Bianca Cappello: chapter 2 considers Fonte’s Medici genealogy as a response to a specific political moment and to the unique anxieties of her first dedicatee, while chapter 3 explores how Fonte’s history of Venice functions as a civic genealogy for her second.

Unter Verwendung von Dichtefunktionaltheorie werden die katalytischen Eigenschaften von Cerdioxidoberflächen mit verschiedenen Terminierungen untersucht. Cerdioxid wird auch als Trägermaterial in der heterogenen Katalyse eingesetzt, um Aktivität, Selektivität und Stabilität der aktiven Komponente zu erhöhen. In dieser Arbeit werden geträgerte Vanadiumoxidcluster diskutiert. Dabei wird die oxidative Dehydrierung von Methanol als Modellreaktion zur Aktivierung von C-H-Bindungen genutzt. Ceroxidpartikel werden oft in wässriger Lösung synthetisiert. Damit hängt die Form der Nanokristallite direkt von der relativen Stabilität der unterschiedlichen Terminierungen in der Gegenwart von Wasser ab. Außerdem ist Wasser an zahlreichen Reaktionen entweder als Produkt, Edukt oder Lösungsmittel beteiligt. Aus diesem Grund werden auch die Wasser-Oberflächenwechselwirkungen untersucht. Des Weiteren wird die Genauigkeit von drei verschiedenen Funktionalen (B3LYP, HSE und PBE+U) durch den Vergleich mit experimentellen Daten evaluiert. Diese beinhalten Barrieren, die mittels Temperatur-programmierter Desorptionsspektroskopie erhalten wurden, und Schwingungsspektren. / Density functional theory is applied to study the catalytic properties of ceria surfaces with different terminations. Ceria is also used as a support material in heterogeneous catalysis to improve activity, selectivity, and stability of the active component. In this work, supported vanadia clusters are discussed. The oxidative dehydrogenation of methanol is used as a model reaction for C–H bond activation. Ceria catalysts are often prepared in aqueous solution. As a result, the shape of ceria nanocrystallites depends on the relative stability of the different surface terminations in the presence of water. Furthermore, many reactions involve water either as a product, as a reagent, or as a solvent. Hence, water–surface interactions are studied as well. Furthermore, the accuracy of three different functionals (B3LYP, HSE, and PBE+U) is assessed by comparison to experimental data such as barriers obtained via temperature-programmed desorption and infrared spectra.

Although it is generally acknowledged that an Elizabethan grammar school education was intensely oral and aural, few studies have approached the literature of its pupils principally in light of such an understanding. There may be good reason for this paucity, since the reading of textual remains in the hopes of reconstituting sound and movement—particularly in non-dramatic literature—will always, in the end, be confronted by an inaudible and static text. Yet for the Elizabethan schoolboy, composition and performance were inseparable, whether of an epistle, a theme, or a translation of Latin poetry. The purpose of this project is firstly to describe the conditions which led to and ingrained that inseparability, and then offer some readings of the poetry, oratory, and drama of those whose voices and pens were trained in the grammar school, here Merchant Taylors’ School in 1560s London. Edmund Spenser, Lancelot Andrewes, and Thomas Kyd all attended Merchant Taylors’ in this period, and their poetry, sermons, and drama, respectively, are treated in the following discussion. It is argued that their texts reflect the same preoccupation with pronuntiatio et actio, or rhetorical delivery, held by their boyhood schoolmaster, Richard Mulcaster. I suggest that delivery provides a unique way of assessing literature in the context of an oral/aural education, largely because its classical and Renaissance rules invariably stipulate that vocal and gestural modulations must follow the emotional and intentional sense of words rather than their literal meanings. Delivery is thus shown to exist at the nexus of orality and literacy, performance and text, wholly absorbed with the concerns of speech, but distinct from language as well. In imagining the physicality of this middle ground within their narratives, it is proposed that Mulcaster’s students recalled an education very often spent stirring the emotions with and for their bodily expression.

Chemische Reaktionen in der Natur sowie Prozesse in synthetischen Materialien werden oft erst durch die Wechselwirkung von Licht mit Materie ausgelöst. Üblicherweise werden diese komplexen Prozesse mit Hilfe von Näherungen beschrieben. Im ersten Teil der Arbeit wird die Gültigkeit der Born-Oppenheimer Näherung in einem vibronischen Modellsystem (Trans-Polyacetylene) unter Photoelektronenspektroskopie im Gleichgewicht sowie zeitaufgelöster Photoelektronenspektroskopie im Nichtgleichgewicht überprüft. Die vibronische Spektralfunktion zeigt aufgrund des faktorisierten Anfangs- und Endzustandes in der Born-Oppenheimer Näherung zusätzliche Peaks, die in der exakten Spektralfunktion nicht auftreten. Im Nichtgleichgewicht zeigen wir für eine Franck-Condon Anregung und eine Anregung mit Pump-Probe Puls, wie die Bewegung des vibronischen Wellenpaktes im zeitabhängigen Photoelektronenspektrum verfolgt werden kann. Im zweiten Teil der Arbeit werden sowohl die Materie als auch das Licht quantisiert behandelt. Für eine volle quantenmechanische Beschreibung des Elektron-Licht Systems, verwenden wir die kürzlich entwickelte quantenelektrodynamische Dichtefunktionaltheorie (QEDFT) für gekoppelte Elektron-Photon Systeme. Wir zeigen erste numerische QEDFT-Berechnungen voll quantisierter Atome und Moleküle in optischen Kavitäten, die an das quantisierte elektromagnetische Feld gekoppelt sind. Mit Hilfe von Fixpunktiterationen berechnen wir das exakte Kohn-Sham Potential im diskreten Ortsraum, wobei unser Hauptaugenmerk auf dem Austausch-Korrelations-Potential liegt. Wir zeigen die erste Näherung des Austausch-Korrelations-Potentials mit Hilfe eines optimierten effektiven Potential Ansatzes angewandt auf einen Jaynes-Cummings-Dimer. Die dieser Arbeit zugrunde liegenden Erkenntnisse und Näherungen ermöglichen es neuartige Phänomene an der Schnittstelle zwischen den Materialwissenschaften und der Quantenoptik zu beschreiben. / Many natural and synthetic processes are triggered by the interaction of light and matter. All these complex processes are routinely explained by employing various approximations. In the first part of this work, we assess the validity of the Born-Oppenheimer approximation in the case of equilibrium and time-resolved nonequilibrium photoelectron spectra for a vibronic model system of Trans-Polyacetylene. We show that spurious peaks appear for the vibronic spectral function in the Born-Oppenheimer approximation, which are not present in the exact spectral function of the system. This effect can be traced back to the factorized nature of the Born-Oppenheimer initial and final photoemission states. In the nonequilibrium case, we illustrate for an initial Franck-Condon excitation and an explicit pump-pulse excitation how the vibronic wave packet motion can be traced in the time-resolved photoelectron spectra as function of the pump-probe delay. In the second part of this work, we aim at treating both, matter and light, on an equal quantized footing. We apply the recently developed quantum electrodynamical density-functional theory, (QEDFT), which allows to describe electron-photon systems fully quantum mechanically. We present the first numerical calculations in the framework of QEDFT. We focus on the electron-photon exchange-correlation contribution by calculating exact Kohn-Sham potentials in real space using fixed-point inversions and present the performance of the first approximate exchange-correlation potential based on an optimized effective potential approach for a Jaynes-Cummings-Hubbard dimer. This work opens new research lines at the interface between materials science and quantum optics.

In the vast realm of inorganic materials, the Cu2+-containing cuprates form one of the richest classes. Due to the combined effect of crystal-field, covalency and strong correlations, all undoped cuprates are magnetic insulators with well-localized spins S=1/2, whereas the charge and orbital degrees of freedom are frozen out. The combination of the spin-only nature of their magnetism with the unique structural diversity renders cuprates as excellent model systems. The experimental studies, boosted by the discovery of high-temperature superconductivity in doped La2CuO4, revealed a fascinating variety of magnetic behaviors observed in cuprates. A digest of prominent examples should include the spin-Peierls transition in CuGeO3, the Bose-Einstein condensation of magnons in BaCuSi2O6, and the quantum critical behavior of Li2ZrCuO4. The magnetism of cuprates originates from short-range (typically, well below 1 nm) exchange interactions between pairs of spins Si and Sj, localized on Cu atoms i and j. Especially in low-dimensional compounds, these interactions are strongly anisotropic: even for similar interatomic distances |Rij|, the respective magnetic couplings Jij can vary by several orders of magnitude. On the other hand, there is an empirical evidence for the isotropic nature of this interaction in the spin space: different components of Si are coupled equally strong. Thus, the magnetism of cuprates is mostly described by a Heisenberg model, comprised of Jij(Si*Sj) terms. Although the applicability of this approach to cuprates is settled, the model parameters Jij are specific to a certain material, or more precisely, to a particular arrangement of the constituent atoms, i.e. the crystal structure. Typically, among the infinite number of Jij terms, only several are physically relevant. These leading exchange couplings constitute the (minimal) microscopic magnetic model. Already at the early stages of real material studies, it became gradually evident that the assignment of model parameters is a highly nontrivial task. In general, the problem can be solved experimentally, using elaborate measurements, such as inelastic neutron scattering on large single crystals, yielding the magnetic excitation spectrum. The measured dispersion is fitted using theoretical models, and in this way, the model parameters are refined. Despite excellent accuracy of this method, the measurements require high-quality samples and can be carried out only at special large-scale facilities. Therefore, less demanding (especially, regarding the sample requirements), yet reliable and accurate procedures are desirable. An alternative way to conjecture a magnetic model is the empirical approach, which typically relies on the Goodenough-Kanamori rules. This approach links the magnetic exchange couplings to the relevant structural parameters, such as bond angles. Despite the unbeatable performance of this approach, it is not universally applicable. Moreover, in certain cases the resulting tentative models are erroneous. The recent developments of computational facilities and techniques, especially for strongly correlated systems, turned density-functional theory (DFT) band structure calculations into an appealing alternative, complementary to the experiment. At present, the state-of-the-art computational methods yield accurate numerical estimates for the leading microscopic exchange couplings Jij (error bars typically do not exceed 10-15%). Although this computational approach is often regarded as ab initio, the actual procedure is not parameter-free. Moreover, the numerical results are dependent on the parameterization of the exchange and correlation potential, the type of the double-counting correction, the Hubbard repulsion U etc., thus an accurate choice of these crucial parameters is a prerequisite. In this work, the optimal parameters for cuprates are carefully evaluated based on extensive band structure calculations and subsequent model simulations. Considering the diversity of crystal structures, and consequently, magnetic behaviors, the evaluation of a microscopic model should be carried out in a systematic way. To this end, a multi-step computational approach is developed. The starting point of this procedure is a consideration of the experimental structural data, used as an input for DFT calculations. Next, a minimal DFT-based microscopic magnetic model is evaluated. This part of the study comprises band structure calculations, the analysis of the relevant bands, supercell calculations, and finally, the evaluation of a microscopic magnetic model. The ground state and the magnetic excitation spectrum of the evaluated model are analyzed using various simulation techniques, such as quantum Monte Carlo, exact diagonalization and density-matrix renormalization groups, while the choice of a particular technique is governed by the dimensionality of the model, and the presence or absence of magnetic frustration. To illustrate the performance of the approach and tune the free parameters, the computational scheme is applied to cuprates featuring rather simple, yet diverse magnetic behaviors: spin chains in CuSe2O5, [NO]Cu(NO3)3, and CaCu2(SeO3)2Cl2; quasi-two-dimensional lattices with dimer-like couplings in alpha-Cu2P2O7 and CdCu2(BO3)2, as well as the 3D magnetic model with pronounced 1D correlations in Cu6Si6O18*6H2O. Finally, the approach is applied to spin liquid candidates --- intricate materials featuring kagome-lattice arrangement of the constituent spins. Based on the DFT calculations, microscopic magnetic models are evaluated for herbertsmithite Cu3(Zn0.85Cu0.15)(OH)6Cl2, kapellasite Cu3Zn(OH)6Cl2 and haydeeite Cu3Mg(OH)6Cl2, as well as for volborthite Cu3[V2O7](OH)2*2H2O. The results of the DFT calculations and model simulations are compared to and challenged with the available experimental data. The advantages of the developed approach should be briefly discussed. First, it allows to distinguish between different microscopic models that yield similar macroscopic behavior. One of the most remarkable example is volborthite Cu3[V2O7](OH)2*2H2O, initially described as an anisotropic kagome lattice. The DFT calculations reveal that this compound features strongly coupled frustrated spin chains, thus a completely different type of magnetic frustration is realized. Second, the developed approach is capable of providing accurate estimates for the leading magnetic couplings, and consequently, reliably parameterize the microscopic Hamiltonian. Dioptase Cu6Si6O18*6H2O is an instructive example showing that the microscopic theoretical approach eliminates possible ambiguity and reliably yields the correct parameterization. Third, DFT calculations yield even better accuracy for the ratios of magnetic exchange couplings. This holds also for small interchain or interplane couplings that can be substantially smaller than the leading exchange. Hence, band structure calculations provide a unique possibility to address the interchain or interplane coupling regime, essential for the magnetic ground state, but hardly perceptible in the experiment due to the different energy scales. Finally, an important advantage specific to magnetically frustrated systems should be mentioned. Numerous theoretical and numerical studies evidence that low-dimensionality and frustration effects are typically entwined, and their disentanglement in the experiment is at best challenging. In contrast, the computational procedure allows to distinguish between these two effects, as demonstrated by studying the long-range magnetic ordering transition in quasi-1D spin chain systems. The computational approach presented in the thesis is a powerful tool that can be directly applied to numerous S=1/2 Heisenberg materials. Moreover, with minor modifications, it can be largely extended to other metallates with higher value of spin. Besides the excellent performance of the computational approach, its relevance should be underscored: for all the systems investigated in this work, the DFT-based studies not only reproduced the experimental data, but instead delivered new valuable information on the magnetic properties for each particular compound. Beyond any doubt, further computational studies will yield new surprising results for known as well as for new, yet unexplored compounds. Such "surprising" outcomes can involve the ferromagnetic nature of the couplings that were previously considered antiferromagnetic, unexpected long-range couplings, or the subtle balance of antiferromagnetic and ferromagnetic contributions that "switches off" the respective magnetic exchange. In this way, dozens of potentially interesting systems can acquire quantitative microscopic magnetic models. The results of this work evidence that elaborate experimental methods and the DFT-based modeling are of comparable reliability and complement each other. In this way, the advantageous combination of theory and experiment can largely advance the research in the field of low-dimensional quantum magnetism. For practical applications, the excellent predictive power of the computational approach can largely alleviate designing materials with specific properties.