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The g - and - h distributional family is generated from a relatively simple transformation of the standard normal. By changing the skewness and elongation parameters g and h, this distributional family can approximate a broad spectrum of commonly used distributional shapes, such as normal, lognormal, Weibull and exponential. Consequently, it is easy to use in simulation studies and has been applied in multiple areas, including risk management, stock return analysis and missing data imputation studies. The current available methods to estimate the g - and - h distributional family include: letter value based method (LV), numerical maximal likelihood method (NMLE), and moment methods. Although these methods work well when no outliers or contaminations exist, they are not resistant to a moderate amount of contaminated observations or outliers. Meanwhile, NMLE is a computational time consuming method when data sample size is large. In this dissertation a quantile based least squares (QLS) estimation method is proposed to fit the g - and - h distributional family parameters and then derive its basic properties. Then QLS method is extended to a robust version (rQLS). Simulation studies are performed to compare the performance of QLS and rQLS methods with LV and NMLE methods to estimate the g - and - h parameters from random samples with or without outliers. In random samples without outliers, QLS and rQLS estimates are comparable to LV and NMLE in terms of bias and standard error. On the other hand, rQLS performs better than other non-robust method to estimate the g - and - h parameters when moderate amount of contaminated observations or outliers exist. The flexibility of the g - and - h distribution and the robustness of rQLS method make it a useful tool in various fields. The boxplot (BP) method had been used in multiple outlier detections by controlling the some-outside rate, which is the probability of one or more observations, in an outlier-free sample, falling into the outlier region. The BP method is distribution dependent. Usually the random sample is assumed normally distributed; however, this assumption may not be valid in many applications. The robustly estimated g - and - h distribution provides an alternative approach without distributional assumptions. Simulation studies indicate that the BP method based on robustly estimated g - and - h distribution identified reasonable number of true outliers while controlling number of false outliers and some-outside rate compared to normal distributional assumption when it is not valid. Another application of the robust g - and - h distribution is as an empirical null distribution in false discovery rate method (denoted as BH method thereafter). The performance of BH method depends on the accuracy of the null distribution. It has been found that theoretical null distributions were often not valid when simultaneously performing many thousands, even millions, of hypothesis tests. Therefore, an empirical null distribution approach is introduced that uses estimated distribution from the data. This is recommended as a substitute to the currently used empirical null methods of fitting a normal distribution or another member of the exponential family. Similar to BP outlier detection method, the robustly estimated g - and - h distribution can be used as empirical null distribution without any distributional assumptions. Several real data examples of microarray are used as illustrations. The QLS and rQLS methods are useful tools to estimate g - and - h parameters, especially rQLS because it noticeably reduces the effect of outliers on the estimates. The robustly estimated g - and - h distributions have multiple applications where distributional assumptions are required, such as boxplot outlier detection or BH methods. / Statistics

Radio frequency spectrum is a scarce natural resource that is utilized for many services including surveillance, navigation, communication, and broadcasting. Recent years have seen tremendous growth in use of spectrum especially by commercial cellular operators. As a result, cellular operators are experiencing a shortage of radio spectrum to meet bandwidth demands of users. Spectrum sharing is a promising approach to solve the problem of spectrum congestion as it allows cellular operators access to more spectrum in order to satisfy the ever growing bandwidth demands of commercial users. The US spectrum regulatory bodies are working on an initiative to share 150 MHz of spectrum, held by federal agencies, in the 3.5 GHz band with commercial wireless operators. This band is primarily used by radar systems that are critical to national defense. Field tests have shown that spectrum sharing between radars and communication systems require large separation distance in order to protect them from harmful interference. Thus, novel methods are required to ensure spectrum sharing between the two systems without the need of large protection distances. In order to efficiently share spectrum between radars and communication systems at the same time and in the same geographical area, a novel method is proposed that transforms radar signal in such a way that it does not interfere with communication systems. This is accomplished by projecting the radar signal onto null space of the wireless channel between radar and communication system. In order to understand the effects of the proposed sharing mechanism -- in urban, sub-urban, and littoral areas -- new channel models, specifically, two- and three-dimensional channel models are designed that capture azimuth and elevation angles of communication systems and helps in placing accurate nulls. In addition, interference coming from communication systems into radar receivers is analyzed and radar performance is accessed. Using this information, resource allocation schemes are designed for communication systems that take advantage of the carrier aggregation feature of the LTE-Advanced systems. This further helps in dynamic sharing of spectrum between radars and communication systems. The proposed signal projection approach not only meets radar objectives but also meets spectrum sharing objectives. However, there is a trade-off as signal projection results in some performance degradation for radars. Performance metrics such as probability of target detection, Cramer Rao bound and maximum likelihood estimate of target's angle of arrival, and beampattern of radar are studied for performance degradation. The results show minimal degradation in radar performance and reduction in exclusion zones, thus, showing the efficacy of the proposed approach. / Ph. D.

L’étude porte sur les catégories "signes" (Zeichen) et "traces" (Spuren) dans l’œuvre poétique et les déclarations poétologiques de Günter Eich (1907-1972). Signes naturels, linguistiques, traces biographiques et intertextuelles, relevé de stigmates historiques (Spurensicherung) imprègnent l’œuvre sous forme d’images poétiques et de concepts poétologiques. Complémentaires ou opposés, ils éclairent le parcours complexe du poète, du déchiffrement des signes naturels au souhait tardif de "ne pas laisser de traces", de la collecte de traces au tracé de l’écriture (et à son effacement) dans des textes lus comme des palimpsestes d’écrits antérieurs. A partir de documents d’archives inédits (manuscrits, correspondances, notes), de bibliothèques d’auteurs et d’entretiens avec des proches du poète, le rôle des signes et des traces dans les relations entre écriture poétique et réalité exogène est examiné en croisant processus d’écriture (méthodes de critique génétique) et réception des textes, celle-ci orientant à son tour les tracés poétiques ultérieurs. Le travail montre les interactions entre lecture et écriture du monde, le traitement des signes et traces étant à la fois un acte de déchiffrement et l’esquisse d’un nouveau balisage poétique (Zeichen-Setzung) du langage et du réel. Cette nouvelle approche de l'évolution de la poétique et de la poésie de Günter Eich éclaire le rapport problématique du poète au réel, à la tradition lyrique et à l’histoire de son temps en situant son œuvre au confluent de problématiques romantiques anciennes et d’une nouvelle fonction de la poésie née de la situation historique. / This study probes into the categories of “signs” (Zeichen) and “traces” (Spuren) in Günter Eich's poetic œuvre and poetological statements. Natural and linguistic signs, biographical and intertextual traces, accounts of historical stigmas (Spurensicherung) permeate his work through poetic images and poetological concepts. Whether complementary or antagonistic, they shed light on the poet's complex progress, from the deciphering of natural signs to his late desire to “leave no trace”, from the collecting of traces to the traces of writing (and its erasure) within texts that are read as the palimpsests of former writings. Relying on unpublished archives (manuscripts, correspondences, notes), on authors' private collections and on interviews of the poet's relatives and friends, we show how signs and traces shape out the relationships between poetic writing and the outer reality through a cross-study of writing processes (using genetic criticism) and the reception of texts (which, in turn, shapes out future poetic tracings). This study shows the interactions between the reading and the writing of the world, the treatment of signs and traces being both an act of deciphering and the sketching out of a new poetic marking out (Zeichen-Setzung) of language and of the real world. This new approach of the evolution of Günter Eich's poetics and poetry accounts for the poet's problematic relation to reality, to the lyrical tradition and to contemporary history by situating his work at the junction of ancient romantic issues and of a new function of poetry born from the historical context.

Whether species interactions are static or change over time has wide-reaching ecological and evolutionary consequences. However, species interaction networks are typically constructed from temporally aggregated interaction data, thereby implicitly assuming that interactions are fixed. This approach has advanced our understanding of communities, but it obscures the timescale at which interactions form (or dissolve) and the drivers and consequences of such dynamics. We address this knowledge gap by quantifying the within-season turnover of plant-pollinator interactions from weekly censuses across 3years in a subalpine ecosystem. Week-to-week turnover of interactions (1) was high, (2) followed a consistent seasonal progression in all years of study and (3) was dominated by interaction rewiring (the reassembly of interactions among species). Simulation models revealed that species' phenologies and relative abundances constrained both total interaction turnover and rewiring. Our findings reveal the diversity of species interactions that may be missed when the temporal dynamics of networks are ignored.

Au cours de ce travail, nous avons utilisé des souris ayant une délétion totale (KO) ou partielle (hétérozygotes) du gène codant la protéine STOP. La souris KO STOP constitue un modèle reconnu pour l’étude de la physiopathologie de la schizophrénie (SCH). Ce travail a permis d’étendre les données disponibles en mettant en évidence chez la souris KO STOP des troubles comportementaux qui miment les symptômes apparentés à l’ensemble des dimensions de la SCH. La comparaison des déficits chez des souris KO STOP générées à partir de différentes souches a permis de montrer que la délétion du gène STOP induit un phénotype robuste. De plus, notre travail permet de suggérer que, de par leur construction et leur phénotype, la souris hétérozygote STOP évoque la vulnérabilité à la SCH et pourrait constituer un modèle animal pertinent pour étudier les facteurs qui, interagissant avec une vulnérabilité génétique, favoriserait la décompensation psychotique. Dans cette optique, nous avons étudié l’influence de différents types de stress chroniques appliqués à différents moments clés du développement sur le phénotype de nos modèles animaux. Aucun des stress utilisés (isolement, stress chronique multiple, privation maternelle) n’a modifié le phénotype des souris hétérozygotes STOP à l’âge adulte, ni dans le sens de l’émergence ni dans celui d’une aggravation de troubles apparentés à la symptomatologie de la SCH. Ces résultats posent la question du type de stress, de son intensité et de la fenêtre temporelle où il doit être appliqué qui, associé à une altération génique donnée, validerait le modèle physiopathologique actuel basé sur une interaction délétère entre vulnérabilité et stress / In this work, we used mice with total (STOP null) or partial deletion (heterozygous) for the gene encoding the STOP protein. STOP null mice represent a recognized model for studying the physiopathology of schizophrenia (SCH). This work allowed us to extend the available phenotype by showing that STOP null mice exhibit various behavioural impairments mimicking symptoms corresponding to all SCH dimensions. By comparing the alterations present in STOP null mice generated from various strains, we showed that the STOP deletion induces a robust phenotype linked to SCH. In addition, through their construct and phenotype validity, the present work allows us to suggest that the STOP heterozygous mice evoke SCH vulnerability and could be a relevant model for studying the parameters which could favour SCH when interacting with a genetic vulnerability. In this context, the effects of chronic stress applied at different key steps of the mouse development were studied on the phenotype of our animal models. Any stress paradigm used (short-term isolation, chronic multiple stress, maternal deprivation) has been not able to alter the phenotype of STOP heterozygous mice measured in adulthood, neither by inducing nor by worsening alterations linked to SCH. According to the current SCH physiopathology hypothesis based on a deleterious interaction between susceptibility to SCH and stress, our findings raise the question regarding the type of stress paradigm, including stress intensity and the time window where it is applied, that could induce frank psychosis when interacting with a specific genetic alteration

Doctor of Philosophy / Department of Statistics / Gary L. Gadbury / High-throughput metabolite analysis is an approach used by biologists seeking to identify the functions of genes. A mutation in a gene encoding an enzyme is expected to alter the level of the metabolites which serve as the enzyme’s reactant(s) (also known as substrate) and product(s). To find the function of a mutated gene, metabolite data from a wild-type organism and a mutant are compared and candidate reactants and products are identified. The screening principle is that the concentration of reactants will be higher and the concentration of products will be lower in the mutant than in wild type. This is because the mutation reduces the reaction between the reactant and the product in the mutant organism. Based upon this principle, we suggest a method to screen the possible lipid reactant and product pairs related to a mutation affecting an unknown reaction. Some numerical facts are given for the treatment means for the lipid pairs in each treatment group, and relations between the means are found for the paired lipids. A set of statistics from the relations between the means of the lipid pairs is derived. Reactant and product lipid pairs associated with specific mutations are used to assess the results. We have explored four methods using the test statistics to obtain a list of potential reactant-product pairs affected by the mutation. The first method uses the parametric bootstrap to obtain an empirical null distribution of the test statistic and a technique to identify a family of distributions and corresponding parameter estimates for modeling the null distribution. The second method uses a mixture of normal distributions to model the empirical bootstrap null. The third method uses a normal mixture model with multiple components to model the entire distribution of test statistics from all pairs of lipids. The argument is made that, for some cases, one of the model components is that for lipid pairs affected by the mutation while the other components model the null distribution. The fourth method uses a two-way ANOVA model with an interaction term to find the relations between the mean concentrations and the role of a lipid as a reactant or product in a specific lipid pair. The goal of all methods is to identify a list of findings by false discovery techniques. Finally a simulation technique is proposed to evaluate properties of statistical methods for identifying candidate reactant-product pairs.

A teoria do limite de similaridade é uma teoria central para o entendimento da estruturação das comunidades ecológicas, e prevê que a coexistência de duas espécies de forma estável somente é possível caso exista um limite de semelhança entre elas. Nesse sentido, é esperado que ocorra partilha de recursos entre espécies simpátricas aparentadas como Podocnemis unifilis e Podocnemis expansa, dois quelônios amplamente distribuídos e de grande importância econômica e cultural na região amazônica. Assim, o objetivo deste estudo foi determinar os padrões de consumo de duas espécies simpátricas de quelônios, P. unifilis e P. expansa, além de verificar possíveis interações tróficas que se estabeleçam entre elas, considerando suas possíveis variações sexuais, no rio Javaés, Estado do Tocantins, Brasil. Desta forma, foram feitas análises dos conteúdos estomacais e análises isotópicas das unhas de indivíduos dessas espécies visando a determinação de suas amplitudes e sobreposições de nicho alimentar e isotópico. As sobreposições de nicho alimentar foram comparadas às sobreposições de comunidade idealizadas sem competição, por meio de modelos nulos. As sobreposições de nicho isotópico foram calculadas através de elipses bayesianas. As espécies apresentaram baixos valores de amplitude de nicho independente da medida. Entretanto, apresentaram alta sobreposição de nicho alimentar e nenhuma sobreposição de nicho isotópico. Amplitudes foram sempre reduzidas e sobreposições sempre elevadas entre os sexos. As diferenças entre as sobreposições de nicho das espécies medidas a partir das duas metodologias se relacionaram a importância de outras dimensões além da alimentar para o nicho isotópico. Os padrões de uso de recursos observados indicam que competição por alimento não está sendo relevante para a coocorrência das espécies no sistema estudado, possivelmente devido à altas disponibilidades dos recursos alimentares utilizados por P. unifilis e P. expansa. / The limiting similarity theory is a central theory for the comprehension of the structure of ecological communities, and predicts that the stable coexistence of two species is possible only if there is a limit of similarity between them. Therefore, it is expected to occur resource partitioning among sympatric related species as Podocnemis unifilis and Podocnemis expansa, two freshwater turtles widely distributed and of great economic and cultural importance in the Amazon region. The objective of this study was to determine the consumption patterns of two sympatric species of freshwater turtles, P. unifilis and P. expansa, and to identify possible trophic interactions to be established between them, considering its possible sexual variations, in the Javaés River, State of Tocantins, Brazil. Thus, were made analyzes of stomach content and isotopic analyzes of claws from individuals of these species in order to determine their amplitudes and dietary overlaps of food niche and isotopic niche. The food niche overlaps were compared with overlaps of idealized communities without competition, through null models. The isotopic niche overlaps were calculated using bayesian ellipses. The species had low niche amplitude values independent of the measure. However, the species showed high overlap of food niche and no isotopic niche overlap. Amplitudes were always reduced and overlap always high between the sexes. Differences between the niche overlaps of the species measures due the two methodologies were related to the importance of other dimensions beyond that represented by feeding to the isotopic niche. The observed patterns of resources usage indicate that competition for food is not being relevant to the co-occurrence of these species in the system studied, possibly due to the high availability of food resources used by P. unifilis and P. expansa.

Cette thèse a pour objet l'étude de la contrôlabilité à zéro de systèmes d'équations aux dérivées partielles paraboliques, que l'on rencontre en physique, chimie ou en biologie. En chimie ou en biologie, ces systèmes modélisent l'évolution au cours du temps d'une concentration chimique ou de la densité d'une population (de bactéries, de cellules). Le but de la contrôlabilité à zéro est d'amener la solution du système à l'état nul à un temps donné T, en agissant sur le système à l'aide d'un contrôle. Nous recherchons donc un contrôle, de norme minimale, tel que la solution associée y vérifie y(T)=O dans le domaine Omega considéré. Les problèmes de contrôlabilité à zéro considérés dans cette thèse sont de trois types. Dans un premier temps, nous nous intéressons à la contrôlabilité à zéro avec un nombre fini de contraintes sur la dérivée normale de l'état, pour l'équation de la chaleur semi-linéaire. Puis, nous analysons la contrôlabilité simultanée à zéro avec contrainte sur le contrôle, pour un système linéaire de deux équations paraboliques couplées. Notre dernière étude concerne la contrôlabilité à zéro d'un système non linéaire de deux équations paraboliques couplées. Nous abordons ces problèmes de contrôlabilité principalement à l'aide d'inégalités de Carleman. En effet, l'étude des problèmes de contrôlabilité à zéro, et plus généralement de contrôlabilité exacte, peut se ramener à l'établissement d'inégalités d'observabilité pour le problème adjoint, conséquences d'inégalités de Carleman. Nous construisons le contrôle optimal en utilisant la méthode variationnelle et nous le caractérisons par un système d'optimalité / This thesis is devoted to the study of the null controllability of systems of parabolic partial differential equations, which we meet in physics, chemistry or in biology. In chemistry or in biology, the se systems model the evolution in time of a chemical concentration or the density of a population (of bacteria, cells). The aim of nu Il controllability is to lead the solution of the system to zero in a given time T, by acting on the system with a control. Thus we are looking for a control, of minimal norm, such as the associated solution y satisfies y(T)=O in the domain Omega under concern. We consider three types of null controllability problems in this thesis. At first, we are interested in the null controllability with afinite number of constraints on the normal derivative of the state, for the serni-Iinear heat equation. Then, we analyze the simultaneous null controllability with constraint on the control, for a linear system of two coupled parabolic equations. Our last study deals with the null controllability ofa non linear system oftwo coupled parabolic equations. We approach these controllability problems mainly by means of Carleman's inequalities. Indeed, the study of null controllability problems, and more generally exact controllability problems, is equivalent to obtain observability inequalities for the adjoint problem, consequences of Carleman's inequalities. We build the optimal controlusing the variationnal method and we characterize it by an optimality system

Submitted by Caroline Xavier (caroline.xavier@pucrs.br) on 2017-06-30T18:45:11Z No. of bitstreams: 1 DIS_RENATO_AUGUSTO_VORTMANN_DE_BARBA_COMPLETO.pdf: 961856 bytes, checksum: 3bc19ee0642b80af8997a18416275a99 (MD5) / Made available in DSpace on 2017-06-30T18:45:11Z (GMT). No. of bitstreams: 1 DIS_RENATO_AUGUSTO_VORTMANN_DE_BARBA_COMPLETO.pdf: 961856 bytes, checksum: 3bc19ee0642b80af8997a18416275a99 (MD5) Previous issue date: 2017-01-19 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / Dentro da teoria gerativa dos princ?pios e par?metros (Chomsky, 1981), categorias vazias s?o entidades utilizadas nas an?lises sint?ticas para que certas estruturas lingu?sticas n?o violem princ?pios universais (Mioto, 2007). O portugu?s brasileiro (PB) faz uso de v?rias dessas categorias em diferentes estruturas, e uma das estruturas permitidas pela l?ngua ? o fen?meno conhecido como object drop, ou objeto foneticamente nulo. Em estudos de Aquisi??o de Segunda L?ngua (SLA, no original), a teoria de Transfer?ncia Total / Acesso Total (Schwartz & Sprouse, 1996) postula que o est?gio inicial do L2 ? o est?gio final do L1, mas ao encontrar estruturas que n?o s?o permitidas pela sintaxe da L1, os aprendizes acessam a GU para redefinir par?metros relacionados ?s estruturas. Considerando que o PB ? frequentemente aprendido ap?s outra l?ngua adicional, sendo assim uma L3, o Modelo da Supremacia Tipol?gica (TPM, no original) proposto por Rothman (2010) afirma que a transfer?ncia ocorrer? a partir da gram?tica da l?ngua percebida como a mais semelhante, mesmo se a transfer?ncia de outra l?ngua fosse mais facilitadora. O presente estudo aplicou uma tarefa de julgamento de aceitabilidade com diferentes estruturas em PB tanto para os falantes nativos (n = 27) quanto para os aprendizes de PB (L1 espanhol, L2 ingl?s) (n = 15) para poder comparar sua avalia??o dessas estruturas. Esperava-se que, como PB e espanhol s?o percebidos como tipologicamente mais pr?ximos, os aprendizes de PB transfeririam seus conhecimentos da L1 ao avaliar as frases em PB. Os resultados demonstram que os falantes nativos t?m avalia??es diferentes dependendo da estrutura que est? sendo testada, com objetos nulos sendo preferidos em ora??es simples, mas nenhuma prefer?ncia clara em estruturas com ilhas sint?ticas fortes. Os aprendizes de PB n?o demonstraram qualquer prefer?ncia por objetos nulos ou abertamente realizados em estruturas com ilhas sint?ticas fortes, mas mostraram prefer?ncia por objetos nulos em ora??es simples com referentes [?definido]. Assumindo FT/FA e TPM, parece que os aprendizes de PB continuam utilizando a gram?tica de sua L1 na avalia??o de algumas das estruturas, enquanto que em outras estruturas parece haver alguma converg?ncia na gram?tica alvo, o que sugere poss?vel acesso ? GU. / Within the generative theory of principles and parameters (Chomsky, 1981), empty categories are entities used in syntactic analyses so that certain language structures do not violate universal principles (Mioto, 2007). Brazilian Portuguese (BP) makes use of several of these categories in different structures, and one of the structures allowed by the language is the phenomenon known as object drop, or phonetically null objects. In studies of Second Language Acquisition (SLA), the theory of Full Transfer / Full Access (Schwartz & Sprouse, 1996) posits that the initial stage of the L2 is the final stage of the L1, but in finding structures that are not allowed by the L1 syntax, learners access the UG to reset parameters related to these structures. Considering BP is often learned after another additional language, hence being an L3, the Typological Primacy Model (TPM) proposed by Rothman (2010) claims that transfer will occur from the grammar of the language perceived as the most similar, even if transfer from another language would be more facilitative. The present study contains results of an acceptability judgment task with different structures in BP given to both Native speakers (n = 27) and BP learners (L1 Spanish, L2 English)(n = 15). It was expected that, because BP and Spanish are perceived as typologically closer, BP learners would transfer their knowledge from the L1 while evaluating the sentences in BP. The results show that Native speakers have different evaluations depending on the structure being tested, with null objects being preferred in Simple clauses, but no clear preference in structures with strong syntactic islands. The BP learners did not show any clear preference for null or overt objects in structures with strong syntactic islands, but showed preference for null objects in Simple clauses with [? definite] referents. Assuming FT/FA and the TPM, it seems that BP learners kept using the grammar from their L1 in evaluating some of the structures, while in other structures there seems to be some convergence on the target grammar, hinting at some level of access to UG.