Dissertations / Theses on the topic 'Divergenza'

Nella tesi vengono presentati due degli strumenti più utilizzati nel calcolo integrale in più variabili: il teorema della Divergenza e il teorema di Stokes, entrambi prima in un caso generale, poi nel caso tridimensionale. Prima di arrivare a questi due risultati, introdurremo gli strumenti necessari per l'integrazione su aperti regolari e di calcolo vettoriale esterno. Una volta dimostrati i due teoremi, arriveremo ad enunciare le leggi di Maxwell in forma integrale per trasformarle, applicando i due risultati, in forma differenziale: queste equazioni saranno il nostro punto di partenza per la ricerca di una soluzione per l'equazione d'onda, che definiremo onda elettromagnetica, che governa le interazioni tra campo elettrico e campo magnetico. Utilizzeremo i risultati ottenuti matematicamente per dare al fenomeno un'interpretazione fisica.

The purpose of this dissertation is to prove that the Dirichlet problem in a bounded domain is uniquely solvable for elliptic equations in divergence form. The proof can be achieved by Hilbert space methods based on generalized or weak solutions. Existence and uniqueness of a generalized solution for the Dirichlet problem follow from the Fredholm alternative and weak maximum principle.

Dopo aver introdotto le quantità fondamentali per lo studio della curvatura delle superfici, mappa di Gauss, curvatura media e gaussiana, ed aver enunciato e provato il teorema della divergenza nello spazio tridimensionale, si dimostreranno le formule di Minkowski; in ultimo saranno presentati come corollari i teoremi di Hilbert-Liebmann e di Jellett.

Questo lavoro fornisce un importante contributo sulla genetica del genere Salamandrina, un endemita italiano. La variazione delle sequenze di tre geni mitocondriali è stata esaminata su campioni provenienti dall’intero areale distributivo. I risultati indicano l’esistenza di due geneticamente distinti e quasi vicarianti linee mitocondriali, tanto da costituire molto probabilmente due buone specie. Sono anche state studiate la variabilità genetica, l’analisi demografica e la struttura di popolazione. Inoltre sono stati indagati e discussi i probabili scenari paleogeografici che avrebbero determinato la separazione delle due linee dal progenitore comune. I risultati assumo importanti risvolti per la gestione e la conservazione di queste salamandre, attualmente già protette da numerose convenzioni e direttive, a livello internazionale, nazionale e regionale.
This work provides important contribute on the genetics of the Italian endemic genus Salamandrina The whole distribution range was examined for sequence variation of three mitochondrial DNA genes. Results indicate the existence of two genetically distinct and almost geographically nonoverlapping mtDNA lineages which should be considered as two full species. Genetic variability, demographic analysis and population structure were also carried out. Furthermore possible palaeogeographic scenarios which could have shaped the splitting of the two 6DODPDQGULQD lineages are discussed. These findings have also important implications for management and conservation of this salamander which is protected under several international and regional conventions and directives.

Il punto centrale della tesi è stato dimostrare il Teorema di Koebe per le funzioni armoniche. È stato necessario partire da alcuni risultati di integrazione in Rn per ricavare identità e formule di rappresentazione per funzioni di classe C2, introdurre le funzioni armoniche e farne quindi una analisi accurata. Tali funzioni sono state caratterizzate tramite le formule di media e messe in relazione con le funzioni olomorfe, per le quali vale una formula simile di rappresentazione.

Scopo della tesi è di estendere un celebre teorema di Montel, sulle famiglie normali di funzioni olomorfe, all'ambiente sub-ellittico delle famiglie di soluzioni u dell'equazione Lu=0, dove L appartiene ad un'ampia classe di operatori differenziali alle derivate parziali reali del secondo ordine in forma di divergenza, comprendente i sub-Laplaciani sui gruppi di Carnot, i Laplaciani sub-ellittici su arbitrari gruppi di Lie, oltre all'operatore di Laplace-Beltrami su varietà di Riemann. A questo scopo, forniremo una versione sub-ellittica di un altro notevole risultato, dovuto a Koebe, che caratterizza le funzioni armoniche come punti fissi di opportuni operatori integrali di media con nuclei non banali. Sarà fornito anche un adeguato sostituto della formula integrale di Cauchy.

La seguente tesi è composta da quattro capitoli. I capitoli sono quattro articoli indipendenti l’uno dall’altro. I primi tre articoli si riferiscono al contesto della Federazione Russa, mentre l’ultimo a quello dell’Unione Indiana. In tutti i lavori si utilizzano metodi di econometria che si adattano al meglio a dati regionali e, in tre capitoli su quattro, ciò implica l’utilizzo di tecniche di econometria spaziale. Nei paragrafi successivi si riassumono i contenuti e i principali risultati conseguiti in ciascuno dei capitoli. Il primo capitolo studia il processo di convergenza tra le regioni russe utilizzando metodi di econometria spaziale, in complemento alle tradizionali tecniche per lo studio di convergenza derivate dalla teoria economica neoclassica. L’analisi copre l’arco temporale 1999-2004. Un processo di convergenza assoluta sembra essere assente in Russia e questo risultato conferma i risultati di altri lavori antecedenti. Il coefficiente di convergenza beta comincia ad essere significativamente negativo solo dopo l’inserimento di altre variabili esplicative oltre al livello iniziale di reddito procapite. Il modello neoclassico di convergenza condizionata risulta sovrastimare il coefficiente di convergenza beta rispetto al caso in cui si inserisca un ritardo spaziale della variabile dipendente. Ciò sembra rafforzare l’ipotesi di una distorsione dei modelli neoclassici applicati a dati regionali indotta dalla presenza di una dipendenza spaziale nei dati. Le distorsioni indotte dagli effetti spaziali risultano ancora più evidenti con l’utilizzo di metodi di econometria panel. La componente spaziale sembra quindi avere un ruolo non risibile nello spiegare il processo di convergenza tra le regioni russe. Inoltre, variabili come l’estrazione di idrocarburi, il livello di apertura al commercio, e gli investimenti diretti esteri, risultano tutte avere un impatto positivo e statisticamente positivo sulla crescita economica. Il secondo capitolo si concentra sul ruolo degli idrocarburi come possibile determinante della concentrazione del reddito. Il primo capitolo aveva già mostrato come gli idrocarburi costituissero un fattore molto importante nello spiegare lo sviluppo inter-regionale in Russia. Il presente articolo mostra e discute come gli idrocarburi siano anche un importante determinante della concentrazione del reddito all’interno delle regioni russe. Dopo aver discusso la letteratura rilevante concernente le determinanti della concentrazione del reddito tra paesi e all’interno della Russia, si mostra empiricamente quali siano le determinanti intra-regionali della concentrazione del reddito in Russia, facendo uso di modelli panel dinamici. I risultati tendono a confermare che le regioni dove il petrolio e il gas vengono prodotti tendono ad avere livelli di concentrazione del reddito più alti. Il terzo capitolo è dedicato all’analisi degli investimenti diretti esteri (IDE) in Russia. Più in particolare, si esplora l’ipotesi di effetti spaziali nella distribuzione degli IDE tra le regioni russe. Il modello utilizzato descrive gli IDE come risultanti da un effetto di agglomerazione (il livello degli IDE in una regione dipende positivamente dal livello di FDI nelle regioni circostanti) e un effetto di isolamento ( la distanza di ogni regione dai più importanti investitori internazionali). Considerando un panel di 68 regioni russe per il periodo 2000-2004, si rileva che entrambi gli effetti abbiano un ruolo significativo nel determinare i flussi di IDE nella Federazione Russa. I due effetti risultano significativi anche dopo l’inserimento di una serie di variabili ci controllo che sono state rilevate importanti fattori dei flussi di IDE tra paesi (il potenziale del mercato circostante, le infrastrutture, un indice del clima degli investimenti). Nel quarto ed ultimo capitolo, si analizza il processo di convergenza/divergenza tra gli stati indiani. Dopo aver revisionato tutte le principali riforme economiche implementate durante gli ultimi decenni nell’Unione Indiana, si conduce uno studio econometrico delle determinanti della crescita economica nel quadro neoclassico del modello di Solow. Uno degli aspetti più importanti dello studio è di nuovo l’applicazione di tecniche di econometria spaziale a complemento delle tecniche neoclassiche. Si controlla per due effetti spaziali distinti, un effetto di distanza di ogni regione rispetto a tutte le altre e un effetto di condivisione di un confine. I nostri risultati sembrano suggerire che la disparità tra regioni più ricche e più povere sia costantemente aumentata durante gli anni ottanta e novanta. Più specificamente si rileva che i vincitori sono risultati essere quegli stati che hanno beneficiato maggiormente delle riforme di liberalizzazione, grazie anche ad un vantaggio derivante dalla loto posizione geografica e alla presenza di un settore dei servizi già sviluppato. Le regioni che invece mostrano un arretramento economico più marcato sono risultate essere quelle prive di uno sbocco al mare, altamente popolate, con la presenza predominante del settore agricolo e poco innovative.
This thesis consists of four separate chapters, which are all in themselves self standing. The first three papers refer to the Russian Federation context, while the last one to the Indian Union’s one. The liaison linking all the works is represented by the use of econometrics techniques, which better adapt to regional datasets and, in the most of cases, this implies the use of spatial econometrics tools. Here below I briefly summarize the contents and main findings of each of the chapters. The first paper analyses the process of convergence across Russian regions using spatial econometrics tools in addition to the traditional -convergence techniques as derived from the neoclassical theoretical setting. The study covers the period 1999-2004. Absolute convergence is absent, confirming the results obtained in previous studies on the Russian Federation. The convergence coefficient begins to be significant only after the introduction of other explanatory variables in addition to the initial level of per capita income. The neoclassical conditional convergence model is found to overestimate the absolute value of β with respect to its spatial lag model counterpart, strengthening the hypothesis of a bias due to spatial dependence in the data. When moving to the panel data analysis, the gap in convergence coefficient becomes more evident and slightly present also in the spatial error model. The spatial component appears to be non-negligible and, consequently, conventional convergence estimates suffer a bias due to spatial dependence across observations. Furthermore, variables such as hydrocarbon supply, openness to trade and FDI per capita are found to have an unambiguous, positive and statistically significant impact on growth. Results are also confirmed by the panel data specifications of the models. The second chapter focuses on the role of hydrocarbons as a possible determinant for inequality. Already in the first chapter I showed that hydrocarbons are one of the main elements constituting the great divide across fast and slow growing Russian regions. Here we concentrate mainly on the role of oil and gas as a possible determinant of within region inequality. After having reviewed the economic literature concerning determinants of inequality across countries and within Russia, we test empirically the determinants of intra-regional inequality in Russia, applying robust dynamic panel data estimators. We find that regions where oil and gas is produced tend to experience higher levels of income inequality in striking resemblance to cross-country results. The third chapter is devoted to the analysis foreign direct investment in Russia. More in particular, we explore the hypothesis of spatial effects in the distribution of Foreign Direct Investments (FDI) across Russian regions. We make use of a model, which describes FDI inflows as resulting from an agglomeration effect (the level of FDI in a given region depends positively on the level of FDI received by the regions in its neighbourhood) and remoteness effect (the distance of each Russian regions from the most important outflows countries). Considering a panel of 68 Russian regions over the period 2000-2004 we find that the two effects play a significant role in determining FDI inflows towards Russia. The two effects are also robust to the inclusion of other widely used explanatory variables impacting the level of FDI towards countries or regions (e.g. surrounding market potential, infrastructures, investment climate). In the fourth and last chapter, we investigate the process of convergence/divergence across Indian states. After surveying the main economic reforms implemented during the last decades in the Indian Union, we conduct an econometric study of the determinants of economic growth in the neoclassical frame of the Solow model. One of the main novel aspects of our convergence analysis is the attention paid to the spatial pattern of growth across Indian states. Making use of spatial econometric tools, we control for two different kinds of spatial interaction: distance and neighbourhood. Our results suggest that the gap between poor and rich states has constantly increased during the 1980s and the 1990s. Specifically, we find that winners were those states that benefited the most from the recent process of reform and liberalization, thanks also to their geographical advantage and to the presence of a developed service sector. Losers were instead the landlocked and highly populated states with a predominant agricultural sector and a low level of innovation.

In questo lavoro di tesi si è scelto di approfondire le tematiche relative ad alcuni aspetti della sicurezza del processo di ossidazione parziale dell’etilene. Infatti, nonostante l’elevato mercato a livello mondiale, la produzione dell’ossido di etilene è ad oggi fortemente limitata dalla necessità di ridurre i rischi di esplosione e di perdita di controllo del reattore. Per tale motivo, in una prima fase, sono stati descritti e confrontati criticamente i principali processi attualmente utilizzati e le proprietà dei composti coinvolti. Successivamente, a partire dai dati di letteratura raccolti, sono stati sviluppati i diagrammi di stabilità dell’ossido di etilene al variare delle condizioni operative, all’interno di intervalli tipici degli impianti industriali analizzati e dei parametri monitorati. Questa analisi ha permesso l’individuazione di tre regioni di interesse: Hot Spot (HS), Runaway (RUN) e Pseudo Adiabatic Operation (PAO). Tale analisi è stata condotta, in prima battuta, considerando un reattore in stato stazionario e una cinetica semplificata, contenente le principali reazioni catalitiche. Successivamente, è stato introdotto un modello cinetico di dettaglio in grado di includere le reazioni in fase elementari omogenee ed è stata rimossa l’ipotesi di stazionarietà. Inoltre, sono stati calcolati gli andamenti della selettività, resa e conversione al variare delle condizioni operative. Questo approccio ha permesso la simultanea inclusione di aspetti cinetici, termici e massici, rappresentando un aspetto fondamentale per l’applicazione del paradigma QFS, indicante come processo ottimale quello avente cinetiche rapide (Quick), elevate selettività (Fair) e livelli di sicurezza (Safe).

Nel lavoro si dimostrano il Teorema della Divergenza e il Teorema di Stokes e le sue generalizzazioni a una curva chiusa di ordine k e a una varietà M, n-dimensionale, orientata con bordo. Successivamente si espongono due applicazioni alla fisica: l'elettromagnetismo e la formula del rotore. Nel primo caso si mostra come applicando il Teorema alle leggi di Biot-Savarat e di Faraday si ottengono le equazioni di Maxwell; nel secondo invece si osserva come il rotore rappresenti la densità superficiale di circuitazione.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES
La vita politica e gli elementi che la costituiscono sono sempre stati e restano ancora oggi oggetti di studio della filosofia politica. Le discussioni su come gli uomini devono strutturarsi politicamente, nel miglior modo possibile, hanno permeato tutti i periodi della storia della filosofia, in particolar modo nei pensieri politici di vari autori, e casi non rari sotto molti punti di vista contrastanti. In questo lavoro, si propone di discutere i testi di Machiavelli riguardanti gli elementi strutturanti della vita politica, sottolineando il tipo di rapporto che può esistere tra dissensi di umori e libertà repubblicana. Basandosi su questa analisi, si discute l'originalità dell'autore sul tema e anche le condizioni che, secondo lui, fanno con cui i conflitti siano convergenti con la libertà, così come quelli che li rendono dannosi alla vita libera.
A vida política e os elementos que a constituem sempre foram e continuam sendo objetos de estudo da filosofia política. As discussões em torno de como os homens devem se estruturar politicamente, da melhor maneira possível, têm perpassado todos os períodos da história da filosofia, destacando-se nos pensamentos políticos de diversos autores, e em não raros casos, sob perspectivas bastante divergentes. Neste trabalho, propomos discutir os textos de Maquiavel no que concerne aos elementos estruturantes da vida política, dando ênfase ao tipo de relação que pode haver entre as dissensões dos humores e a liberdade republicana. Com base nessa análise, discutiremos a originalidade do autor acerca deste assunto e, igualmente, as condições que, segundo ele, tornam os conflitos convergentes com a liberdade, assim como aquelas que os tornam nocivos à vida livre.

Oggetto di studio di questa tesi sono le funzioni armoniche. Inizialmente abbiamo introdotto le nozioni principali (definizione di funzione armonica e calcolo esplicito delle funzioni radiali armoniche). Dopo aver enunciato e dimostrato il teorema della divergenza e la prima e seconda identità di Green ci siamo ricavati le formule di rappresentazione di Green. Successivamente, dopo aver calcolato il volume e l'area di bordo di una palla euclidea, abbiamo introdotto le formule di media del Laplaciano. Una loro diretta conseguenza è la Disuguaglianza di Harnack, che abbiamo enunciato e dimostrato inizialmente per una palla e poi generalizzato a un compatto. Abbiamo poi visto un'applicazione di questa disuguaglianza: il teorema di Liouville. Infine abbiamo illustrato il principio del massimo (minimo) forte e del massimo (minimo) debole.

L’adaptació al canvi climàtic és un procés complex i dinàmic que s’ha observat que provoca capacitats adaptatives desiguals entre els múltiples actors d’un sistema socioecològic (SSE). Partint de les teories dels SSE sobre adaptació, aquesta tesi formula la pregunta: Com es relaciona l’adaptació divergent amb el conflicte i la cooperació en un SSE rural compartit entre actors pastorals i agro-pastorals? Per tal d’examinar les dinàmiques socials, ecològiques, institucionals i climàtiques, la tesi introdueix el concepte d’adaptació “divergent”. L’adaptació és divergent quan l’adaptació d’un grup d’actors provoca la subseqüent reducció de la capacitat adaptativa d’un altre grup d’actors en el mateix ecosistema, la qual cosa pot estar lligada a dinàmiques de cooperació i de conflicte. Per tal d’entendre l’adaptació divergent, he realitzat un estudi al Níger, un país amb nivells baixos de capacitat adaptativa que està situat al cor de la regió del Sahel-Sàhara, a l’Àfrica occidental. Diferents àrees d’estudi van ser seleccionades d’entre tres zones ecològiques a la regió de Tahoua: Tillia (una àrea principalment de pastura a la zona plujosa del Sahel-Sàhara), Keita (una àrea agro-pastoral a la zona del Sahel), i Madaoua (una zona principalment agrícola en el límit de la zona sudanesa-saheliana). La recerca ha tingut com a objectius: 1) entendre les percepcions dels canvis històrics, presents i futurs en els serveis dels ecosistemes i els mitjans de vida relacionats; 2) identificar les capacitats adaptatives dels múltiples actors; 3) explicar el ritme i el volum de la creació de “enclosures” al voltant de llacs efímers i permanents; i 4) analitzar les institucions multiescalars que donen suport a l’organització de l’espai rural i a la resolució dels seus conflictes. Les adaptacions divergents descrites en aquest estudi inclouen: l’expansió de cultius en zones de pastura, la introducció de pagaments per l’accés a l’aigua, i el desenvolupament d’horts de regadiu en llacs estacionals. L’adaptació divergent pot ser un procés que aporta més cooperació i equitat a la societat o pot augmentar els patrons ja arrelats d’injustícia i desigualtat. És un procés determinat pels patrons de degradació dels serveis dels ecosistemes, els règims canviants de propietat de la terra rellevants per les adaptacions, i el tipus i influència de les institucions en el procés d’adaptació. Basat en un exàmen exhaustiu de les adaptacions divergents, els resultats mostren que en les tres zones ecològiques l’expansió de cultius continua reemplaçant els sistemes mòbils de pasturatge, provocant conflictes en algunes ocasions. En aquest context, els mitjans de vida que depenen dels serveis dels ecosistemes d’aprovisionament i suport de l’agricultura són més destructius pels serveis múltiples que no pas els mitjans de vida i actors que es basen en el pasturatge. A Tillia, el foment dels pagaments per l’aigua contribueix als canvis en curs dels els règims de gestió de la terra, on els recursos passen de ser comuns i compartits a ser propietat privada. En una de les àrees de la zona oficial de pastures, la construcció de tancats al voltant de basses de reg comunes ha crescut a un ritme del 124% en un període de nou anys. Malgrat l’existència de lleis adequades per protegir els espais de pastures, aquestes rarament són aplicades, un problema agreujat pels conflictes en la governança, per una baixa responsabilitat i per la corrupció. Els participants en un grup de discussió sobre escenaris futurs de canvi climàtic van estar d’acord de manera unànime en què a les zones de pastures s’hi seguiran construint tancats i seran cultivades, atès especialment a què els pastors s’estan instal·lant en els poblats. L’adaptació divergent és un concepte de gran actualitat que pot ser de suma importància per a l’estudi de com l’adaptació i les capacitats adaptatives dels múltiples actors poden contribuir al conflicte i a la cooperació en el context de canvi climàtic. Aquesta tesi demostra empíricament la diversitat de fenòmens socials i ecològics que poden explicar el concepte d’adaptació divergent i contribueix en diversos àmbits científics i polítics pertinents per a la capacitat d’adaptació en SSE.
Climate change adaptation is a complex and dynamic process that has been found to produce unequal adaptive capacities for multiple users across a social ecological system (SES). Stemming from SES theories on adaptation, this thesis asks the question: How does divergent adaptation link to conflict and cooperation in a rural ‘farmer-herder’ SES? To examine social, ecological, institutional and climatic dynamics, the thesis introduces the concept ‘divergent’ adaptation. Adaptation is divergent when one user or group’s adaptation causes a subsequent reduction in another user or group’s adaptive capacity in the same ecosystem, which may be linked to cooperation and conflict dynamics. To understand divergent adaptation, I performed a case study land and water use conflicts within and between agro-pastoral and pastoral groups in Niger, a country with low levels of adaptive capacity that is located in the heart of the Sahel-Sahara region of West Africa. Sites were selected within three ecological zones in the region of Tahoua: Tillia (a primarily pastoral area in the Sahelo-Saharan rainfall zone), Keita (an agro-pastoral area in the Sahel zone), and Madaoua (a primarily agricultural area on the edge of the Sudano-Sahel zone). The research aimed to: 1) understand perceptions of historical, present, and future changes to ecosystem services and related livelihoods; 2) identify the adaptive capacities of multiple users; 3) explain the pace and volume of the development of enclosures around ephemeral and permanent lakes; and 4) analyze multi-scalar institutions supporting the organization of the rural space and resolution of land and water access conflicts therein. The divergent adaptations described in this study include: expanding cultivation into pastoral areas, introducing payments for water access, and developing irrigated gardening on seasonal lakes. Divergent adaptation can be a process that builds more cooperation and equity in society or enhances entrenched patterns of injustice and inequality, a process determined by the patterns of degradation of ecosystem services, the shifting land tenure regimes relevant to adaptations, and the type and influence of institutions on the adaptation process. Based on a rigorous examination of divergent adaptations, findings show that across the three ecological zones, expanding cultivation continues to supersede mobile pastoral systems, sometimes resulting in conflict. In this context, the cultivating livelihoods dependent upon certain ecosystem services for agricultural production are more destructive to multiple ecosystem services than the livelihoods of pastoralists and the users themselves. In Tillia, the exhortation of water payments contributes to the ongoing shifts of land management regimes from commonly-shared to privately owned resources. In one location in the official pastoral zone, fencing-in of common watering holes has grown at a rate of 124% over a period of nine years as a result of irrigated gardening. While the Rural and Pastoral Codes are in place to protect pastoral space, they are rarely enforced, a problem exacerbated by conflicting governance, low accountability, and corruption. Stakeholders at climate change scenario focus group, unanimously agree that pasture will continue to be enclosed and cultivated, especially as pastoralists settle in villages, thus constraining resources. Divergent adaptation is a state-of-the-art concept relevant for the study of how the differential adaptive capacities of multiple users contributes to conflict and cooperation in the context of climate change. Given the empirical findings, this thesis demonstrates the need for more equitable and inclusive decision-making processes at multiple scales of adaptation in the SES.

Mémoire (M.Ed)--Université du Québec à Chicoutimi, 1986.
"Mémoire présenté à l'Université du Québec à Chicoutimi en vue de l'obtention de la maîtrise en éducation" CaQCU Document électronique également accessible en format PDF. CaQCU

Predmet istraživanja ovog rada je istraživanje i eksploatacija mogućnosti da parametri Gausovih komponenti korišćenih Gaussian mixture modela  (GMM) aproksimativno leže na niže dimenzionalnoj površi umetnutoj u konusu pozitivno definitnih matrica. U tu svrhu uvodimo novu, mnogo efikasniju meru sličnosti između GMM-ova projektovanjem LPP-tipa parametara komponenti iz više dimenzionalnog parametarskog originalno konfiguracijskog prostora u prostor značajno niže dimenzionalnosti. Prema tome, nalaženje distance između dva GMM-a iz originalnog prostora se redukuje na nalaženje distance između dva skupa niže dimenzionalnih euklidskih vektora, ponderisanih odgovarajućim težinama. Predložena mera je pogodna za primene koje zahtevaju visoko dimenzionalni prostor obeležja i/ili veliki ukupan broj Gausovih komponenti. Razrađena metodologija je primenjena kako na sintetičkim tako i na realnim eksperimentalnim podacima.
This thesis studies the possibility that the parameters of Gaussian components of aparticular Gaussian Mixture Model (GMM) lie approximately on a lower-dimensionalsurface embedded in the cone of positive definite matrices. For that case, we delivernovel, more efficient similarity measure between GMMs, by LPP-like projecting thecomponents of a particular GMM, from the high dimensional original parameter space,to a much lower dimensional space. Thus, finding the distance between two GMMs inthe original space is reduced to finding the distance between sets of lowerdimensional euclidian vectors, pondered by corresponding weights. The proposedmeasure is suitable for applications that utilize high dimensional feature spaces and/orlarge overall number of Gaussian components. We confirm our results on artificial, aswell as real experimental data.

Poche qualità umane hanno un così forte impatto sulla nostra esistenza quanto la creatività (Scott et al., 2004). Il presente progetto di ricerca raccoglie le sfide identificate da Houtz (2003) come cruciali per la ricerca psicologica: riconoscere, potenziare e comprendere la creatività. Il progetto si focalizza sul concetto di pensiero divergente (Guilford, 1956) come risvolto cognitivo della creatività e si divide in tre studi. Il primo studio presenta un contributo alla validazione del Wallach Kogan Creativity Test (1965). Nel secondo studio ill WKCT, validato nel primo studio, insieme al Test di pensiero creativo (Sprini e Tomasello, 1989 - versione italiana del Torrance Test of Creative Thinking, Torrance 1966) è servita per valutare l'efficacia di un training di pensiero creativo. Nel terzo studio a 306 soggetti di seconda media sono stati somministrati i seguenti strumenti: Big Five Questionnaire – Children (Barbaranelli et al.,1998), Test di pensiero creativo - forma A, parte verbale (Sprini e Tomasello, 1989) versione italiana del Torrance Test of Creative Thinking (TTCT; Torrance, 1966) e una serie di item utilizzati da Choi (2004). Quindi è stata condotta una path analysis per testare un modello in cui personalità, motivazione, pensiero divergente e variabili contestuali sono predittori dell'atteggiamento creativo.
Improving creative thinking is a crucial challenge for the progress of human beings and nations (Florida, 2002). The research project aims at recognizing, fostering and understanding divergent thinking (Guilford, 1956) as cognitive aspect of creativity. The project consists of 3 studies. First study is a contribution to the Italian validation of Wallach Kogan Creativity Test (1965) with subjects aged 12. Second study is an experimental research conducted in a school with children 12 years old. A group of them followed a three-months-training that aimed at fostering divergent thinking abilities, another group served as control. Pretest and posttest were administered using Wallach Kogan Creativity Test (1965) previously validated and also the Italian version of Torrance Test of Creative Thinking (Torrance, 1966) in the verbal form (Sprini & Tomasello, 1989). Third study presents a path analysis to test a model in which personality, motivation, divergent thinking and contextual variables are predictors of a creative aptitude.

Cette thèse développe de nouvelles séquences réactionnelles divergentes vers les lactones sesquiterpéniques, ainsi que leurs analogues. La réactivité multiple d’un substrat linéaire face à divers catalyseurs a tout d’abord permis d’obtenir différentes structures polycyliques dont la fonctionnalisation a permis d’isoler plusieurs produits naturels et des analogues. De nouvelles méthodologies ont été étudiées pour accéder aux gamma-butyrolactones, une fonctionnalité prépondérante dans les lactones sesquiterpéniques, ainsi qu’au noyau hydroazulène contenu dans les guaianes. Enfin, une synthèse divergente courte et performante a été mise au point pour accéder à divers analogues de la déoxyéléphantopine, un sesquiterpène aux propriétés anti-cancéreuses, afin de moduler et étudier son activité biologique. En parallèle de ces travaux sur les sesquiterpènes, une autre chimie a été explorée visant à réaliser la glycosylation de cystéines avec des carbohydrates non protégés
The main thread throughout this thesis is to develop reaction sequences that could provide facile access to the sesquiterpene lactones, or analogs thereof, using strategies that would be compatible with divergent reaction pathways. A first project harnessed the multiple reactivity mode of a linea rsubstrate to obtain different polycyclic frameworks found in sesquiterpenes whose functionalisation led to several natural products and their analogs. New methodologies were studied to access gamma-butyrolactones, a preponderant functionality in sesquiterpene lactones, and hydroazulene core, the bicyclic framework of guaianes. Finally, a short divergent pathway was designed to access diverse analogs of deoxyelephantopin, a sesquiterpene showing anti-cancer effects, so as to modulate and study its biological activity. In parallel to this work on sesquiterpenes, a different chemistry was explored aiming at performing glycosylation of cysteines with unprotected carbohydrates

O comportamento do escoamento supersônico no interior de bocais convergente-divergente retangulares é investigado numericamente, comparando-se quatro bocais com diferentes seções divergentes, com a mesma razão de aspecto AR=1.14 e mesma relação áreas da saída e da garganta dos bocais NAR=1.43. Os bocais são submetidos a diferentes pressões de admissão do fluido de trabalho, mantendo-se a relação entre a pressão de admissão e de descarga constante NPR=5. As simulações consideram o escoamento em regime permanente, compressível, viscoso, com abordagem baseada na massa específica (abordagem acoplada) , juntamente com o modelo de turbulência − /SST. A qualidade dos resultados é medida empregando-se três níveis de refino da discretização do domínio computacional, observandose a ordem de convergência e o índice de convergência de malhas GCI. Os resultados numéricos mostram que o número de Mach e a temperatura do fluido de trabalho independem da pressão de admissão, ao contrário do comportamento da pressão local e da massa específica. As propriedades do escoamento são fortemente dependentes da variação da geometria, e a variação do ângulo da seção divergente provoca uma mudança direta do número de Mach e inversa da pressão, da temperatura e da massa específica do escoamento no interior dessa seção. As simulações são comparadas com os resultados da teoria isentrópica e mostram que a linha sônica é deslocada do centro geométrico da garganta dos bocais para cada geometria simulada. A comparação com a teoria e com dados experimentais mostra desvios inferiores a 6x10-3 %. O uso do modelo de turbulência − / SST é capaz de resolver o escoamento com boa precisão, prevendo bem seu perfil de velocidades, as ondas de expansão de Prandtl-Meyer, juntamente com as interações dessas ondas com a camada limite.
The behavior of the supersonic flow inside rectangular convergent-divergent nozzle is investigated numerically by comparing four nozzles with different divergent sections, with a common aspect ratio AR=1.14, and the same nozzle exit-to-throat area ratios NAR=1.43. Nozzles are subject to several working fluid inlet pressures, maintaining a constant pressure ratio NPR=5. Simulations assume the flow in steady state, compressible, viscous, using a coupled approach with the turbulence model − /SST. The quality of results is measured by employing three refining levels of the computational domain discretization, observing the order of convergence and the grid convergence index GCI. Numerical results show that the Mach number and the temperature of the working fluid are independent of the inlet pressure, unlike the behavior of local pressure and the density. Flow properties are strongly dependent on the geometry variation, and the change on the angle of divergent section causes a direct effect on the Mach number and inverse on the pressure, the temperature and the density of the flow in this section. Simulations are compared to the results of the isentropic theory and show that the sonic line is offset from the geometric center of the throat nozzle, for each simulated geometry. Results from this work are compared to experimental and theoretical data and show deviations below 6x10-3 %. The − / SST turbulence model is able to solve the flow with good accuracy, and predicts its velocity profile, Prandtl-Meyer expansion waves, and their interactions with the boundary layer.

The original thesis contains the novel "Stranger, I" as an integral part of the thesis. However this novel has been omitted in this digital copy.
Thesis (MA (Hons))--Macquarie University, Division of Humanities, Department of English, 2006.
Bibliography: p. 93-97.
On divergence in fantasy -- Introduction -- Preliminary -- The thousand and one definitional nights -- Characteristic works: inclusions and exclusions -- Critical objections to fantasy -- Conclusion.
On Divergence in Fantasy explores the ways in which fantasy criticism continually redefines its boundaries, without arriving at agreement. The paper draws on Foucault to suggest that these disputes and dispersions are characteristic of the operation of fantasy critisim as a discursive formation.
Mode of access: World Wide Web.
97 p

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES
Common bean (Phaseolus vulgaris L.) is widely cultivated in Brazil, which is the first biggest producer and consumer in the world. The knowledge about the genetic divergence across landraces is very useful for breeders, once it allows them to organize the genetic resources and explore the genetic variability available. The genetic analysis can be done predicting similarities or dissimilarities coefficients that are estimated by morphological differences between accessions. The objective of this study was to identify the diversity across the accessions of common bean that were collected in Goiás State (Brazil), available in Embrapa Rice and Beans’ germplasm bank, through morphological descriptors and agronomic information. The experimental material was composed by 156 common bean accessions. Two experiments were performed, one of them in a greenhouse (morphologic characterization) and the other one in the field (yield evaluation). The experiment in the greenhouse was conducted using two vases with three seeds each one per accessio), without experimental design. The experiment conducted in the field was done under Federer’s Augmented Blocks design, with four blocks of 43 plots (39 accessions + 4 checks). The accessions were characterized by 39 morpho-agronomic qualitative descriptors and ten quantitative descriptors. The quantitative variables were converted in multicategorical variables. The 39 morpho-agronomic qualitative and the ten quantitative descriptors were transformed in binary variables by creating 236 fictitious variables. Though, the similarity matrix was built, using the model proposed by Harrison, which was converted in a dissimilarity matrix. Then the cluster analysis was performed by UPGMA method. The accessions 101 (Rosinha) x 145 (Pintado)) and 120 (Dobra morro) x 152 (Doidão ou bonitão), were the most divergent, because they showed the lowest similarities value, 0,11. The biggest divergences were observed in accession 152, with the similarity coefficients between 0,11 and 0,52. No redundant accessions were found. The pair 86 (Paraná) x 103 (Amarelinho). showed the biggest similarity (0,84). The accessions were clustered in 17 groups, with cophenetic correlation coefficient equal to 0,75, that was significat by Mantel’s test (P < 0,001).The number of accession per group varied from 43 to one. Four groups with only one accessions were formed, which showed the lowest similarities coefficients. No significance was observed for grain yield a mong the accessions, nor between the accession and the commercial checks.
O feijão (Phaseolus vulgaris L.) é uma cultura amplamente difundida no Brasil, que é o maior produtor e consumidor mundial. O conhecimento da diversidade genética entre as cultivares tradicionais é útil aos melhoristas, por permitir melhor organização dos recursos genéticos e maior aproveitamento da diversidade genética disponível. A análise de divergência genética pode se dar por métodos preditivos, quantificada por medidas de similaridade ou dissimilaridade estimadas com base em diferenças morfológicas. O objetivo deste trabalho foi identificar a existência de diversidade entre os acessos de feijoeiro comum coletados no Estado de Goiás, pertencentes ao Banco de Germoplasma da Embrapa Arroz e Feijão, por meio de descritores morfológicos e informações agronômicas. O material experimental foi formado por 156 acesso de feijoeiro comum coletados no Estado de Goiás. Foram montados dois experimentos um e casa de vegetação (caracterização morfológica) e um em campo (avaliação de produção). No ensaio em casa de vegetação foram utilizados dois vasos com três sementes por acesso, sem delineamento experimental. O experimento em campo foi conduzido em delineamento experimental em blocos aumentados de Federer com 4 blocos, cada um contendo 43 parcelas (39 acessos + 4 testemunhas). Os acessos foram caracterizados com base em 39 descritores morfoagronômicos qualitativos e dez quantitativos. As variáveis quantitativas foram convertidas em variáveis multicategóricas. Tanto os 39 descritores morfoagronômicos qualitativos, quanto os dez quantitativos foram transformados em variáveis binárias resultando em 236 variáveis fictícias. Então foi obtida uma matriz de similaridade, utilizando o modelo de Harrison, que foi convertida em matriz de dissimilaridade; em seguida aplicou-se a análise de agrupamento pelo método UPGMA. Os acessos mais divergentes foram os 101 (Rosinha) x 145 (Pintado) e 120 (Dobra morro) x 152 (Doidão ou bonitão), que apresentaram o menor valor de similaridades 0,11. As maiores divergências foram observadas no acesso 152, com similaridades variando de 0,11 a 0,52. Não foram encontrados acessos redundantes. A maior similaridade foi de 0,84 entre o par de acessos 86 (Paraná) x 103 (Amarelinho). Pela análise de agrupamento os acessos foram agrupados em dezessete grupos, com coeficiente de correlação cofenética (CCC) de 0,75, significativo pelo teste de Mantel (P < 0,001). O número de acessos por grupo variou de 43 a um. Verificou-se a formação de quatro agrupamentos constituídos por apenas um acesso, que apresentaram os menores coeficientes de similaridade. Para produtividade não foi detectada diferença significativa entre acessos e nem entre estes e as testemunhas comerciais.

This thesis concerns different aspects of dating divergence times in phylogenetic trees, using molecular data and multiple fossil age constraints.

Datings of phylogenetically basal eudicots, monocots and modern birds (Neoaves) are presented. Large phylograms and multiple fossil constraints were used in all these studies. Eudicots and monocots are suggested to be part of a rapid divergence of angiosperms in the Early Cretaceous, with most families present at the Cretaceous/Tertiary boundary. Stem lineages of Neoaves were present in the Late Cretaceous, but the main divergence of extant families took place around the Cre-taceous/Tertiary boundary.

A novel method and computer software for dating large phylogenetic trees, PATHd8, is presented. PATHd8 is a nonparametric smoothing method that smoothes one pair of sister groups at a time, by taking the mean of the added branch lengths from a terminal taxon to a node. Because of the local smoothing, the algorithm is simple, hence providing stable and very fast analyses, allowing for thousands of taxa and an arbitrary number of age constraints.

The importance of fossil constraints and their placement are discussed, and concluded to be the most important factor for obtaining reasonable age estimates.

Different dating methods are compared, and it is concluded that differences in age estimates are obtained from penalized likelihood, PATHd8, and the Bayesian autocorrelation method implemented in the multidivtime program. In the Bayesian method, prior assumptions about evolutionary rate at the root, rate variance and the level of rate smoothing between internal edges, are suggested to influence the results.

This document presents a portfolio of ten composition projects produced between September 2010 and June 2014 created by composer Jon Hughes working in collaboration with a number of artists and researchers. Each individual chapter deals with a separate project, and is accompanied by a Data Drive presented alongside the text as an integral part of the submission. This contains audio, video and other supplementary material. There is also an introductory essay, Chapter 1: Footprints and Philosophy: Sonic Explorations in Divergent Landscapes, designed to set the composition portfolio in context. Although contrasting in terms of content and media, the ten works presented here share a number of common conceptual threads. They all involve the use of sound to reveal, uncover, communicate, and to map hidden aspects of the subject matter explored with each individual project, whether that be mathematical principles (Phase Revival), the shared experience of landscape (Terrarium, Hydrology, Another Place), principles from evolutionary biology (Transmission), or the rich complexity of shared acoustic space (A Dip in the Lake). A further related common thread is the use of large-scale ambisonic speaker arrays (Terrarium, A Dip in the Lake, Phase Revival, Sonic Horizons, Hydrology). This gave production teams the ability to create fully immersive audio/visual environments in which hidden themes and concepts referred to above could be better communicated. Working together with fellow collaborators, it thus became possible to create cultural interventions in the form of portable, immersive public spaces. Other themes explored in the portfolio include the use of found sound, and the exploration of landscape narrative. Found sound is used extensively, in combination with instrumental and vocal material.

This study deals with the phenomenon of European integration and its impact on national party programs in Poland, a current member state of the European Union. The author will argue that the question of European integration has left a mark on the political party programs of two mainstream domestic parties on opposite sides of the ideological dimension, in the form of a certain degree of convergence regarding the “European issue”. Relating the result of the analysis to the theoretical structure of Europeanization and sociological institutional change, the essay will attempt to show a possible link between them. Although this trend does not seem to indicate any dramatic effects of the membership per se in the programs (the national arena seems, in most cases, be of more value for party activities) there is an indirect effect in the form of the presence of Europarties and a pronounced incentive for social and economic adaptation.

A method is presented to solve supervisory control problems of discrete event systems and produce divergence-free controllers, which guarantee to avoid unbounded internal communications. The method is described in terms of process spaces, a formalism to model concurrent systems, and applied to safety models. Semantics mappings are described, which relate process spaces to I/O automata and other labeled transition systems. Divergence-free solutions are obtained based on a strong notion of divergence freedom. Our method, which produces the solution for a supervisory control problem, can also detect the absence of such solution and helps to obtain synthesizable specifications for the solutions as well. Finally, a case study is considered where the supervisory control formulation is used to derive the specification of a divergence-free protocol converter to interface two mismatched communication protocols.

Les mathématiques offrent un cadre convenable pour raisonner rigoureusement sur les systèmes et phénomènes réels. Par exemple, en génie logiciel, les méthodes formelles sont parmi les outils les plus efficaces pour détecter les anomalies dans les logiciels. Plusieurs systèmes réels sont stochastiques par nature dans le sens où leur comportement est sujet à un aspect d'incertitude. La représentation de ce genre de systèmes requiert des modèles stochastiques comme les processus de Markov étiquetés (LMP), les processus de Markov décisionnels (MDP), etc. Cette thèse porte sur la quantification de la différence entre les systèmes stochastiques. Les contributions majeures sont : 1. une nouvelle approche pour quantifier la divergence entre les systèmes stochastiques basée sur l'apprentissage par renforcement, 2. une nouvelle famille de notions d'équivalence qui se situe entre l'équivalence par trace et la bisimulation, et 3. un cadre plus flexible pour la définition des notions d'équivalence qui se base sur les tests. Le résultat principal de la thèse est que l'apprentissage par renforcement, qui est une branche de l'intelligence artificielle particulièrement efficace en présence d'incertitude, peut être utilisé pour quantifier efficacement cette divergence. L'idée clé est de définir un MDP à partir des systèmes à comparer de telle sorte que la valeur optimale de cet MDP corresponde à la divergence entre eux. La caractéristique la plus attrayante de l'approche proposée est qu'elle est complètement indépendante des structures internes des systèmes à comparer. Pour cette raison, l'approche peut être appliquée à différents types de systèmes stochastiques. La deuxième contribution est une nouvelle famille de notions d'équivalence, que nous appelons moment, qui est plus forte que l'équivalence par trace mais plus faible que la bisimulation. Cette famille se définit naturellement à travers la coïncidence de moments de variable aléatoires (d'où son nom) et possède une caractérisation simple en terme de tests. Nous montrons que moment fait partie d'un cadre plus grand, appelé test-observation-equivalence (TOE), qui constitue la troisième contribution de cette thèse. Il s'agit d'un cadre plus flexible pour la définition des notions d'équivalence basé sur les tests.
Modelling real-life systems and phenomena using mathematical based formalisms is ubiquitous in science and engineering. The reason is that mathematics offer a suitable framework to carry out formal and rigorous analysis of these systems. For instance, in software engineering, formal methods are among the most efficient tools to identify flaws in software. The behavior of many real-life systems is inherently stochastic which requires stochastic models such as labelled Markov processes (LMPs), Markov decision processes (MDPs), predictive state representations (PSRs), etc. This thesis is about quantifying the difference between stochastic systems. The main contributions are: 1. a new approach to quantify the divergence between pairs of stochastic systems based on reinforcement learning, 2. a new family of equivalence notions which lies between trace equivalence and bisimulation, and 3. a refined testing framework to define equivalence notions. The important point of the thesis is that reinforcement learning (RL), a branch of artificial intelligence particularly efficient in presence of uncertainty, can be used to quantify efficiently the divergence between stochastic systems. The key idea is to define an MDP out of the systems to be compared and then to interpret the optimal value of the MDP as the divergence between them. The most appealing feature of the proposed approach is that it does not rely on the knowledge of the internal structure of the systems. Only a possibility of interacting with them is required. Because of this, the approach can be extended to different types of stochastic systems. The second contribution is a new family of equivalence notions, moment, that constitute a good compromise between trace equivalence (too weak) and bisimulation (too strong). This family has a natural definition using coincidence of moments of random variables but more importantly, it has a simple testing characterization. moment turns out to be part of a bigger framework called test-observation-equivalence (TOE), which we propose as a third contribution of this thesis. It is a refined testing framework to define equivalence notions with more flexibility.

This thesis argues that key aspects of Deleuze's philosophy can be explained by looking closely at his relationship to Leibniz. By confining itself to the particular context and set of terminology which Leibniz's philosophy provides, it hopes to avoid many of the dangers of a more general, and necessarily abstract, interpretation or reconstruction of Deleuze's philosophy. I identify, across Deleuze's career, three distinct, important engagements with Leibniz. In each of these, I argue, Deleuze presents Leibniz as an ambiguous figure, caught somewhere between two opposing tendencies. On the one hand, Deleuze characterises Leibniz's philosophy as the last attempt by theology to ground an ordered world, demonstrated by his preoccupation with questions of harmony and sufficient reason, as well as his insistence that to each kind of problem there must respond a rational principle (the principle of non-contradiction, the principle of the identity of indiscernibles, and so on). But on the other hand, beneath this conservative, theological sentiment, Deleuze also discerns the obscured outlines of a philosophy shot through with dynamism, whose 'dizzying creation' of principles and Baroque complexity reveal an alternative, radicalised image of Leibniz. I argue that from this second, radical Leibniz, Deleuze takes two ideas, returning to them again and again in order to express key aspects of his own philosophy. First, Deleuze believes he has found in Leibniz's theory of 'incompossibility' a concept of difference which is not reducible to a form of opposition between two identities. This theory becomes a crucial component of Deleuze's account of a subrepresentational transcendental field. Second, Deleuze draws on Leibniz's theory that individual monads clearly express a certain region of the world in order to explain how the singular points or events which populate this transcendental field are expressed or actualised by individuals. Explaining how Deleuze appropriates and uses these two ideas provides a narrow point of access into one of the most important areas of his philosophy. At the same time, however, I show that eventually there is always a point where Leibniz's conservative, theological commitments force Deleuze to leave him behind. I thus argue that it is precisely Leibniz's ambiguous status for Deleuze which makes an investigation into their relationship so fruitful: by not only explaining Leibniz's positive influence on Deleuze, but also pinpointing the precise grounds for their eventual divergence, we can better articulate Deleuze's own philosophical priorities.

Texte remanié de: Th. doct.--Sci. écon.--Paris 9, 2002. Titre de soutenance : Nouveau modèle de croissance : une explication des disparités de croissance États-Unis-Europe sur la période 1980-2000.
Bibliogr. p. 331-341.

O complexo Drosophila buzzatii (grupo repleta) compreende 13 espécies, divididas em três clusters, de acordo com o bandeamento observado nos cromossomos politênicos: cluster D. stalkeri, incluindo D. richardsoni e D. stalkeri, restrito às ilhas do Caribe e Flórida; cluster D. martensis, incluindo D. martensis, D. uniseta, D. venezolana e D. starmeri, encontrado em áreas desérticas da Colômbia e Venezuela; e cluster D. buzzatii, incluindo D. buzzatii, D. koepferae, D. antonietae, D. serido, D. gouveai, D. borborema e D. seriema, habitando regiões sazonalmente secas ao longo da diagonal de vegetação aberta da América do Sul. O presente estudo teve como objetivo inferir as relações filogenéticas entre as espécies do complexo D. buzzatii, dando ênfase ao cluster D. buzzatii, por meio de análises multilocus de genes mitocondriais (COI e COII) e nucleares (EF-1F1, transformer e period). Nas hipóteses filogenéticas estabelecidas, as espécies do complexo D. buzzatii constituíram um grupo monofilético, composto por dois subgrupos monofiléticos, os clusters D. martensis e D. buzzatii, e um parafilético, o cluster D. stalkeri. As relações de parentesco entre as espécies do cluster D. buzzatii foram estabelecidas. Drosophila buzzatii ocupou a posição mais basal dentro do cluster D. buzzatii, estando proximamente relacionada à espécie D. koepferae. Drosophila antonietae ocupou uma posição intermediária em relação às espécies D. koepferae e D. serido, que representa o táxon irmão do ramo formado por D. gouveai, D. borborema e D. seriema, com D. gouveai ocupando uma posição mais basal em relação às espécies irmãs D. borborema e D. seriema. Foi detectada seleção purificadora como a principal força dirigindo a evolução dos genes nucleares transformer e period, para as espécies do complexo D. buzzatii. O gene mitocondrial COI, por sua vez, foi utilizado para estimar os tempos de divergência para as espécies do cluster D. buzzatii, revelando que o processo de diversificação do grupo iniciou-se no período Plioceno, provavelmente em decorrência de eventos de vicariância associados à elevação dos Andes, sendo também influenciado pelo avanço e retração da vegetação xerófita, nas flutuações climáticas do Pleistoceno.
Drosophila buzzatii complex (repleta group) consists of 13 species, divided into three clusters according to the banding seen in polytene chromosomes: D. stalkeri cluster, including D. richardsoni and D. stalkeri, restricted to the Caribbean Islands and Florida; D. martensis cluster, including D. martensis, D. uniseta, D. venezuelana and D. starmeri, found in desert areas of Colombia and Venezuela, and D. buzzatii cluster, including D. buzzatii, D. koepferae, D. antonietae, D.gouveai, D. borborema and D. seriema, that inhabit seasonally dry regions along the open vegetation diagonal in South America. This study aimed to infer the phylogenetic relationships among the D. buzzatii species complex, emphasizing the D. buzzatii cluster, by multilocus analysis of mitochondrial (COI and COII) and nuclear (EF-1F1, transformer and period) genes. In established phylogenetic hypotheises, the species of the D. buzzatii complex formed a monophyletic group, composed of two monophyletic subgroups, the D. martensis and D. buzzatii clusters, and a paraphyletic one, the D. stalkeri cluster. The relationships among the D. buzzatii species cluster were established. Drosophila buzzatii occupied the most basal position within the D. buzzatii cluster and is closely related to D. koepferae. D. antonietae occupied an intermediate position in relation to the D. koepferae and D. serido species. D. serido represents the sister taxon of the branch formed by the D. gouveai, D. borborema and D. seriema species, with D. gouveai occupying a basal position in relation to the sister species D. borborema and D. seriema. It was detected that purifying selection is the main force driving the evolution of transformer and period nuclear genes for the species of the D. buzzatii complex. The divergence time of the D. buzzatii species cluster was estimated by the COI gene analysis, revealing that the process of diversification of the group began in the Pliocene period, probably due to vicariant events associated with the uplift phase of the Andes, and it was also influenced by the advance and retraction of xerophytic vegetation in Pleistocene climatic fluctuations.

Questions of the relationships between archaeology and language have long focused on problems of the Indo-European language family. This chapter considers general processes of archaeological and linguistic change with a special focus on language replacement. Here the model of agriculture/language dispersal is particularly significant. The potential contributions of archaeogenetics are also considered.
Por mucho tiempo, las preguntas acerca de las relaciones entre la arqueología y las lenguas se han centrado en los problemas de la familia indoeuropea. En el presente trabajo se tratan procesos generales de cambio de carácter arqueológico y lingüístico, con un énfasis especial en el reemplazo de lenguas. Particularmente significativo es el modelo de la difusión de la agricultura y las lenguas. Asimismo, se debate acerca de las potenciales contribuciones de la arqueogenética.

The thesis "Ecomorphological discrimination of vertebrate sister species with recent phylogenetic divergence using novel non-destructive morphometric methods” compares morphological evolution during syntopic adaptive radiation between two vertebrate classes: the model African cichlid fish and the non-model Malagasy mantellid frogs. In Section I the ontogenetic body shape development of two Lake Victoria haplochromine cichlid sister species (Haplochromis fischeri and H. piceatus) and their non-natural hybrid is described by means of landmark-based Geometric Morphometrics. Chapter 1 relates divergent shape changes in the parental species to their respective trophic specializations and discloses associated shape variation linked to their respective locomotor specializations along the benthic-limnetic axis. Chapter 2 observes their hybrid to display a mosaic of parental and unique morphological features and discusses the influence of hybridization in the radiation of East African cichlids. In Section II computed-tomography (CT) techniques are used to study the musculoskeletal anatomy of mantellid frogs, genus Blommersia. Chapter 3 provides the ecological, morphological, and phylogenetic description of two new species of Blommersia (B. alexi and B. nataliae) found on the Comorian island of Mayotte thought to have evolved in sympatry and to be undergoing opposite processes of gigantism and nanism, respectively, in relation to their most recent common ancestor. Chapter 4 provides the first complete skeletal description for any mantellid species, B. alexi, and reveals genus-specific osteological features that are predicted to be implicated in their locomotion and unique reproductive behavior. Chapter 5 presents a custom soft-tissue contrast staining technique used prior to CT-scanning and applies the recently developed featureless Geometric Morphometric technique of Generalized Procrustes Surface Analysis to compare pelvic shape across seven species of the genus Blommersia, relating observed patterns of shape variation to their phylogenetic relationships and pelvic muscular architecture. In Section III the biomechanics of anuran locomotion are evaluated. Chapter 6 explores biomechanical performance during jumping and swimming locomotion in the wood frog (Rana sylvatica), putting special emphasis on the hindleg musculature implicated in thrust production during both locomotor modes, and reveals incredible physiological resilience as reflected by their relatively unaltered biomechanical performance before and after freezing. Overall, cichlid fish morphological evolution appears to be influenced to a larger degree by trophic ecological pressures, whereas in mantellid frogs it is body size variation and locomotor performance that condition species' divergence.
La tesis "Discriminación ecomorfológica de especies hermanas de vertebradas con divergencia filogenética reciente utilizando nuevos métodos morfométricos no destructivos" compara la evolución morfológica durante la radiación adaptativa sintópica entre dos clases de vertebrados: los peces cíclidos africanos modelo y las ranas mantélidas malgaches no modelo. En la Sección I, el desarrollo ontogenético de la forma del cuerpo de dos especies hermanas de cíclidos haplochrominos del Lago Victoria (Haplochromis fischeri y H. piceatus) y de su híbrido no-natural se describe mediante métodos de Geometría Morfométrica basado en landmarks. El Capítulo 1 relaciona los cambios divergentes en forma entre las especies parentales a sus respectivas especializaciones tróficas y revela variación en forma asociada a sus respectivas especializaciones locomotoras según el eje bentónico-limnético. El capítulo 2 muestra que su híbrido presenta un mosaico de características morfológicas parentales y únicas, y discute la influencia de la hibridación en la radiación de los cíclidos africanos. En la Sección II, se utilizan técnicas de tomografía computarizada (CT) para estudiar la anatomía musculo-esquelética de las ranas mantélidas, género Blommersia. El Capítulo 3 proporciona la descripción ecológica, morfológica, y filogenética de dos nuevas especies de Blommersia (B. alexi y B. nataliae) halladas en la isla comorana de Mayotte, que se cree evolucionaron en simpatría y que están sufriendo procesos opuestos de gigantismo y nanismo, respectivamente, en relación a su ancestro común más reciente. El Capítulo 4 proporciona la primera descripción esquelética completa para cualquier especie de mantélido, B. alexi, y revela características osteológicas específicas del género que se predice que están implicadas en su locomoción y comportamiento reproductivo único. El Capítulo 5 presenta una técnica personalizada de tinción de contraste de tejidos blandos para utilización antes de la CT y aplica la técnica recientemente desarrollada de Geometría Morfométrica para estructuras lisas llamada Generalized Procrustes Surface Analysis para comparar la forma pélvica entre siete especies del género Blommersia, de esta forma relacionando los patrones observados de variación en forma con sus relaciones filogenéticas y arquitectura muscular pélvica. En la Sección III, se evalúa la biomecánica en la locomoción de los anuros. El capítulo 6 explora el rendimiento biomecánico durante la locomoción de salto y natación en la Rana sylvatica, poniendo especial énfasis en la musculatura de la pata trasera implicada en la producción de empuje durante ambos modos locomotores, y revela una increíble resistencia fisiológica reflejada por su rendimiento biomecánico relativamente inalterado antes y después de ser congelado En general, la evolución morfológica en los peces cíclidos parece estar influenciada en mayor medida por las presiones ecológicas tróficas, mientras que en las ranas mantélidas es la variación del tamaño corporal y el rendimiento locomotor lo que condiciona la divergencia de las especies.

Un problema interesante que se plantea en análisis de datos es la elección adecuada de medidas que cuantifiquen las analogías y diferencias entre individuos, poblaciones o grupos de poblaciones.

De forma general, han sido desarrolladas distintas formas de elección de tales medidas, siendo destacables las medidas que provienen de diferencias intrínsecas entre individuos, las medidas que provienen de consideraciones sobre funciones, de entropía, y las medidas que provienen exclusivamente de consideraciones teóricas. En esta memoria, hemos estudiado estas medidas a partir de la clasificación de medidas de distanciación realizada por Burbea y Rao (1982).

En la primera parte (cap. 1, 2 y 3), se presentan las distintas divergencias, se estudian inter-relaciones y se analiza la convexidad.

En la segunda parte (cap. 4) se estudian las métricas diferenciales asociadas a divergencias invariantes frente a cambios no singulares de parámetros y variables aleatorias.

En la tercera parte (cap. 5 y 6) se analizan las relaciones entre la J-divergencia y las entropías comúnmente utilizadas.

Finalmente, en los anexos I y II se presentan los programas utilizados en el cap. 6.

Problems of estimating nonnegative functions from nonnegative data induced by nonnegative mappings are ubiquitous in science and engineering. We address such problems by minimizing an information-theoretic discrepancy measure, namely Csiszar's I-divergence, between the collected data and hypothetical data induced by an estimate. Our applications can be summarized along the following three lines: 1) Deautocorrelation: Deautocorrelation involves recovering a function from its autocorrelation. Deautocorrelation can be interpreted as phase retrieval in that recovering a function from its autocorrelation is equivalent to retrieving Fourier phases from just the corresponding Fourier magnitudes. Schulz and Snyder invented an minimum I-divergence algorithm for phase retrieval. We perform a numerical study concerning the convergence of their algorithm to local minima. X-ray crystallography is a method for finding the interatomic structure of a crystallized molecule. X-ray crystallography problems can be viewed as deautocorrelation problems from aliased autocorrelations, due to the periodicity of the crystal structure. We derive a modified version of the Schulz-Snyder algorithm for application to crystallography. Furthermore, we prove that our tweaked version can theoretically preserve special symmorphic group symmetries that some crystals possess. We quantify noise impact via several error metrics as the signal-to-ratio changes. Furthermore, we propose penalty methods using Good's roughness and total variation for alleviating roughness in estimates caused by noise. 2) Deautoconvolution: Deautoconvolution involves finding a function from its autoconvolution. We derive an iterative algorithm that attempts to recover a function from its autoconvolution via minimizing I-divergence. Various theoretical properties of our deautoconvolution algorithm are derived. 3) Linear inverse problems: Various linear inverse problems can be described by the Fredholm integral equation of the first kind. We address two such problems via minimum I-divergence methods, namely the inverse blackbody radiation problem, and the problem of estimating an input distribution to a communication channel (particularly Rician channels) that would create a desired output. Penalty methods are proposed for dealing with the ill-posedness of the inverse blackbody problem.

Die Entwicklung der deutschen Regionen nach der Wiedervereinigung kann mit Hilfe der Neuen Ökonomischen Geographie erklärt werden. Die gängigen Modelle zeigen aber weder, wie dauerhafte Lohnsatzdifferenzen ohne vollständige Agglomeration entstehen, noch wird die Frage beantwortet, in welcher der betrachteten Regionen sich eine Agglomeration bildet. Diese Lücke wird hier geschlossen, indem das Modell von Ludema und Wooton (1997) erweitert und anschließend auf die Situation in Deutschland angewendet wird.

The Texas endemic silverleaf sunflower, Helianthus argophyllus, exhibits striking genetic variation in life history: some individuals flower in late summer and are relatively short, while other individuals delay flowering in favor of growth until fall. The central goal of this research is to identify and characterize the evolutionary drivers of this variation: either local adaptation under divergent natural selection, neutral phenotypic divergence resulting from reduced gene flow and subsequent genetic drift, or both. Helianthus argophyllus exhibits strong regional genetic structure. However, populations from the central area of the species range form a single genetic cluster but are split into two phenotypic clusters: mainland coast populations, which are primarily tall and late flowering, and barrier island populations, which contain short/early flowering and tall/later flowering individuals at roughly equal frequencies. Some traits, including floral size characters, are more differentiated across the species range than is expected based on neutral genetic divergence (QST > FST), a signal of local adaptation. In a reciprocal transplant experiment, barrier island plants had higher survival rates and overall fitness than non-local individuals at barrier island sites. Observations of selection in wild populations revealed directional selection for early flowering in barrier island populations that contrasts with selection for a later flowering optimum in mainland coast populations. Collectively, these analyses support a hypothesis of adaptive divergence in flowering time in H. argophyllus, although the ecological mechanism(s) and genetic basis of this divergence have yet to be explored.
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