Following the introduction of the discounted penalty function by Gerber and Shiu (1998), significant progress has been made on the analysis of various ruin-related quantities in risk theory. As we know, the discounted penalty function not only provides a systematic platform to jointly analyze various quantities of interest, but also offers the convenience to extract key pieces of information from a risk management perspective. For example, by eliminating the penalty function, the Gerber-Shiu function becomes the Laplace-Stieltjes transform of the time to ruin, inversion of which results in a series expansion for the associated density of the time to ruin (see, e.g., Dickson and Willmot (2005)). In this thesis, we propose to analyze the long-standing finite-time ruin problem by incorporating the number of claims until ruin into the Gerber-Shiu analysis. As will be seen in Chapter 2, many nice analytic properties of the original Gerber-Shiu function are preserved by this generalized analytic tool. For instance, the Gerber-Shiu function still satisfies a defective renewal equation and can be generally expressed in terms of some roots of Lundberg's generalized equation in the Sparre Andersen risk model. In this thesis, we propose not only to unify previous methodologies on the study of the density of the time to ruin through the use of Lagrange's expansion theorem, but also to provide insight into the nature of the series expansion by identifying the probabilistic contribution of each term in the expansion through analysis involving the distribution of the number of claims until ruin. In Chapter 3, we study the joint generalized density of the time to ruin and the number of claims until ruin in the classical compound Poisson risk model. We also utilize an alternative approach to obtain the density of the time to ruin based on the Lagrange inversion technique introduced by Dickson and Willmot (2005). In Chapter 4, relying on the Lagrange expansion theorem for analytic inversion, the joint density of the time to ruin, the surplus immediately before ruin and the number of claims until ruin is examined in the Sparre Andersen risk model with exponential claim sizes and arbitrary interclaim times. To our knowledge, existing results on the finite-time ruin problem in the Sparre Andersen risk model typically involve an exponential assumption on either the interclaim times or the claim sizes (see, e.g., Borovkov and Dickson (2008)). Among the few exceptions, we mention Dickson and Li (2010, 2012) who analyzed the density of the time to ruin for Erlang-n interclaim times. In Chapter 5, we propose a significant breakthrough by utilizing the multivariate version of Lagrange's expansion theorem to obtain a series expansion for the density of the time to ruin under a more general distribution assumption, namely when interclaim times are distributed as a combination of n exponentials. It is worth emphasizing that this technique can also be applied to other areas of applied probability. For instance, the proposed methodology can be used to obtain the distribution of some first passage times for particular stochastic processes. As an illustration, the duration of a busy period in a queueing risk model will be examined. Interestingly, the proposed technique can also be used to analyze some first passage times for the compound Poisson processes with diffusion. In Chapter 6, we propose an extension to Kendall's identity (see, e.g., Kendall (1957)) by further examining the distribution of the number of jumps before the first passage time. We show that the main result is particularly relevant to enhance our understanding of some problems of interest, such as the finite-time ruin probability of a dual compound Poisson risk model with diffusion and pricing barrier options issued on an insurer's stock price. Another closely related quantity of interest is the so-called occupation times of the surplus process below zero (also referred to as the duration of negative surplus, see, e.g., Egidio dos Reis (1993)) or in a certain interval (see, e.g., Kolkovska et al. (2005)). Occupation times have been widely used as a contingent characteristic to develop advanced derivatives in financial mathematics. In risk theory, it can be used as an important risk management tool to examine the overall health of an insurer's business. The main subject matter of Chapter 7 is to extend the analysis of occupation times to a class of renewal risk processes. We provide explicit expressions for the duration of negative surplus and the double-barrier occupation time in terms of their Laplace-Stieltjes transform. In the process, we revisit occupation times in the content of the classical compound Poisson risk model and examine some results proposed by Kolkovska et al. (2005). Finally, some concluding remarks and discussion of future research are made in Chapter 8.

L'analyse des systèmes de grande taille est confrontée à des difficultés d'ordre syntaxique et sémantique : comment observer un million d'entités distribuées et asynchrones ? Comment interpréter le désordre résultant de l'observation microscopique de ces entités ? Comment produire et manipuler des abstractions pertinentes pour l'analyse macroscopique des systèmes ? Face à l'échec de l'approche analytique, le concept d'émergence épistémique - relatif à la nature de la connaissance - nous permet de définir une stratégie d'analyse alternative, motivée par le constat suivant : l'activité scientifique repose sur des processus d'abstraction fournissant des éléments de description macroscopique pour aborder la complexité des systèmes. Cette thèse s'intéresse plus particulièrement à la production d'abstractions spatiales et temporelles par agrégation de données. Afin d'engendrer des représentations exploitables lors du passage à l'échelle, il apparaît nécessaire de contrôler deux aspects essentiels du processus d'abstraction. Premièrement, la complexité et le contenu informationnel des représentations macroscopiques doivent être conjointement optimisés afin de préserver les détails pertinents pour l'observateur, tout en minimisant le coût de l'analyse. Nous proposons des mesures de qualité (critères internes) permettant d'évaluer, de comparer et de sélectionner les représentations en fonction du contexte et des objectifs de l'analyse. Deuxièmement, afin de conserver leur pouvoir explicatif, les abstractions engendrées doivent être cohérentes avec les connaissances mobilisées par l'observateur lors de l'analyse. Nous proposons d'utiliser les propriétés organisationnelles, structurelles et topologiques du système (critères externes) pour contraindre le processus d'agrégation et pour engendrer des représentations viables sur les plans syntaxique et sémantique. Par conséquent, l'automatisation du processus d'agrégation nécessite de résoudre un problème d'optimisation sous contraintes. Nous proposons dans cette thèse un algorithme de résolution générique, s'adaptant aux critères formulés par l'observateur. De plus, nous montrons que la complexité de ce problème d'optimisation dépend directement de ces critères. L'approche macroscopique défendue dans cette thèse est évaluée sur deux classes de systèmes. Premièrement, le processus d'agrégation est appliqué à la visualisation d'applications parallèles de grande taille pour l'analyse de performance. Il permet de détecter les anomalies présentes à plusieurs niveaux de granularité dans les traces d'exécution et d'expliquer ces anomalies à partir des propriétés syntaxiques du système. Deuxièmement, le processus est appliqué à l'agrégation de données médiatiques pour l'analyse des relations internationales. L'agrégation géographique et temporelle de l'attention médiatique permet de définir des évènements macroscopiques pertinents sur le plan sémantique pour l'analyse du système international. Pour autant, nous pensons que l'approche et les outils présentés dans cette thèse peuvent être généralisés à de nombreux autres domaines d'application.

En prenant le soin de dépeindre un tableau de l'immigration étrangère en France telle qu'on la retrouve de nos jours, nous associons à ce travail descriptif une définition de l'intégration dans la société française contemporaine. Il importe après de présenter le contexte général du passage à l'acte délictueux, puis de décrire des mécanismes psychiques sous-jacents à celui-ci. Ceci nous met alors en mesure de développer des réflexions au sujet de dimensions importantes dans cette recherche clinique, comme par exemple celle du double clivage et celle du stress acculturatif. Au sujet des mécanismes psychiques, nous donnons une large place aux rites d'institution de soi, à la négativité, à l'agressivité, à la violence, au lien groupal et bien sûr au rapport entre la migration et la délinquance. Dans la réflexion sur le double clivage, nous nous arrêtons sur l'appartenance culturelle et sur l'identité, et nous mesurons aussi le lien entre l'histoire (ou l'Histoire) et le clivage dedans-dehors, un lien autour duquel prennent toute leur importance les notions de la filiation, de la transmission, du faux self ou encore de l'entre deux. Ensuite, nous rencontrons des notions telles que la vulnérabilité de l'estime de soi, la distorsion cognitive, la violence individuelle, les préjugés de groupe ou encore les processus d'acculturation. Cela nous amène à considérer les liens entre l'assimilation et l'immigration, en prenant le temps de saisir dès lors l'importance prise par la notion de l'honneur chez les jeunes résidant dans des quartiers dits sensibles et issus de populations migrantes. Cela nous permet de passer à une revue des liens potentiels entre le passage à l'acte délinquant et l'estime de soi, ainsi qu'entre le passage à l'acte délinquant et l'anxiété. La première revue nous amène à traiter notamment de la carence d'élaboration psychique et de son déterminisme dans le passage à l'acte délinquant. La deuxième revue nous donne l'occasion de prendre du temps sur l'analyse du modèle cognitif de traitement de l'information spécifique à l'anxiété, ce qui amène à considérer les notions de l'attention sélective et de l'hyper vigilance, ainsi que celle de la phobie sociale. Une dernière revue nous permet d'évoquer la place influente que prend l'exil dans l'histoire d'un sujet et dans l'histoire de sa famille. Cela n'est pas sans lien sur certaines formes de violence ou encore certaines manifestations délictueuses qui surgissent dans l'espace public comme dans l'espace privé.

During the migration season in 2013 a study on spawning migrating salmon and the effect of water flow on the behavior was conducted of the salmon at the Forshaga hydropower station in the River Klarälven. The River Klarälven with its nine hydropower plants on the Swedish side, constituting migration obstacles for the migrating salmon. Fortum Generation AB has together with the County Administrative Board restored a salmon trap at the lowermost hydropower station in Forshaga, aiming at making it possible for the salmon to swim into the trap, and thereafter be transported by truck past the power plants and then continue their journey to the spawning grounds on their own. Unfortunately, it is believed that the trap does not work as well as it should. In this study, I focused on salmon position in relation to water flow and if the number of salmon that swam into the fish trap differed between salmon with previous experience of the trap (experienced) and salmon without experience (unexperienced). My results showed that there were significantly more inexperienced salmon that entered the trap than experienced salmon. The salmon, regardless of experience, chose a position where the flow was highest. To increase catches of salmon in the fish trap I suggest that one use more attraction water and keep the trap open more hours. My results should be of interest to managers as the trap efficiency has never been evaluated, and no earlier studies about the effect of salmon experience on trap efficiency exist. / Vandringssäsongen 2013 genomfördes en studie på lekvandrande lax och hur vattenflödet påverkade laxens beteende vid Forshaga kraftstation i Klarälven. Klarälven med dess 9 vattenkraftverk på den svenska sidan utgör vandringshinder för den lekvandrande laxen. Fortum har tillsammans med Länsstyrelsen renoverat en laxfälla i det mest nedströms liggande kraftverket i Forshaga. Syftet med fällan är att laxen ska simma in i fällan till en uppsamlingsbassäng och därefter köras med lastbil förbi kraftverken, för att därefter fortsätta vandringen på egen hand. Fiskfällans effektivitet är ifrågasatt och man vet inte hur effektiv den är. I denna studie fokuserade jag på laxens ståndplats i relation till varifrån det huvudsakliga flödet kom, samt om antalet laxar som simmar in i fiskfällan skiljde sig mellan lax med tidigare erfarenhet av fällan (erfaren) och lax utan erfarenhet av fällan (oerfaren). Mina resultat visade att det var signifikant fler oerfarna laxar än erfarna laxar som simmade in i fällan. Laxen, oavsett erfarenhet, valde ståndplats där flödet var som högst. För att öka fångsterna av lax i fiskfällan skulle mer lockvatten och fler timmar då fällan är öppen kunna bidra med mer fångst. Denna studie borde vara av intresse för inblandade aktörer i laxens förvaltning eftersom fällans effektivitet aldrig utvärderats tidigare, och dessutom har man inte studerat om tidigare erfarenhet av en fälla påverkar laxen.

This thesis analyzes the presence and progression of the Flying African Myth in Canada— a myth which originally reflected the desires for escape and cross-Atlantic return shared by generations of Black slaves throughout the Americas. While related West African themes of spirit flight and human transformation do suggest a historic relationship, it was only in the New World that human powers of flight emerged. Thus, a new mythology sprung from the desires to transcend the bonds of slavery and return to an African home. However, despite being well documented as Pan-American, this myth has gone largely uninvestigated in its Canadian context thus far— an omission which follows an extensive pattern of Black cultural erasure in Canada as well as the exclusion of Canada in much Black diasporic scholarship. These absences lead to my exploration of the unique circumstances in Canada that continue to influence this myth, including the constant "struggle against erasure" and the “fragile coalition of identities” that constitute the Black diaspora in Canada, as well as federal legislation that protects the nation’s self-image as a multicultural “mosaic.” I argue not only that the myth exists more extensively in Canadian oral and written literatures than may be expected, but that the myth may be alternately interpreted as a method of preserving Canadian national roots as well as navigating Black diasporic routes. I suggest that these two opposing functions of the myth, to pronounce both fixity and fluidity, reflect the tendencies of critics George Elliott Clarke and Rinaldo Walcott to articulate differing approaches to Black identity and culture in Canada. This thesis also embraces the aims set forth in Paul Gilroy’s The Black Atlantic: Modernity and Double-Consciousness, demonstrating how the image of human flight further challenges the oppressive ideologies of Western modernity as well as reimagines the possibilities and implications of the Black diaspora. Indeed, the myth has literally contributed to the formation of the Black diaspora in that it is a cultural artefact shared throughout the Americas and associated with the desire for African return. But the myth also offers a means by which to reconceptualise the structure of the Black diaspora. That is, as the medium of flight, the sky offers an alternative, though equally flexible and more ubiquitous, space for locating the Black diaspora beyond the Atlantic basin. Moreover, the notions of impossibility, immateriality, and imagination which are embraced by this myth circumvent Gilroy’s implicit affirmation of individualism, rationalism, physical mobility, as well as static and bounded geographic space— elements which compromise his productive critique of nationalisms, ethnic essentialisms, and particularly of modernity.

Résumé : L’utilisation de chicanes dans les ponceaux de type insertion en polyéthylène de haute densité (PEHD) est devenue une pratique de plus en plus courante afin d’améliorer les conditions hydrauliques pour le passage des poissons. Cependant, on sait peu sur la façon dont les chicanes affectent la capacité hydraulique des ponceaux. Tout d’abord, une étude comparative a été menée afin de déterminer la variation de la vitesse et de la profondeur entre un ponceau en acier ondulé et un ponceau de type insertion en PEHD pour un débit fixe. Il a été constaté que la vitesse augmentera entre 65% et 260% et la profondeur diminuera entre -58% et -27% selon les valeurs de rugosité réelles du ponceau en tôle ondulée et du ponceau en PEHD. Ces résultats justifient des mesures pour améliorer le passage des poissons, comme par exemple l’installation de chicanes. À cette fin, les coefficients de rugosité n de Manning et f de Darcy ont été déterminés expérimentalement pour les chicanes de type déversoir, les chicanes de type fente et les chicanes de type spoiler pour quatre espacements ( λ = 0.6D , 1.2D, 1.8D, 2.4D ) et trois hauteurs ( h = 0.15D, 0.10D, 0.05D), où D est le diamètre nominal du ponceau. La hauteur des chicanes est ressortie comme étant le paramètre géométrique déterminant affectant la rugosité hydraulique. L’espacement se trouve à jouer un rôle secondaire. Un modèle analytique a été développé et analysé afin de déterminer les effets de la réduction de la rugosité (α = n/nf ), la réduction radiale (β = D/Do), la longueur du ponceau (L) et les traitements d’entrée (ke) sur la capacité hydraulique des ponceaux en tôle ondulée après avoir été réhabilités par insertion d’un ponceau en PEHD. Les résultats montrent que de nombreux ponceaux en PEHD peuvent accueillir des configurations de chicanes ayant des valeurs de α se situant entre 0,5 à 0,9 et continuer de respecter la capacité hydraulique requise. Des recommandations de conception pour l’utilisation de chicanes dans des courts et longs ponceaux en PEHD sont discutées. // Abstract :

In recent years, there has been increased awareness that stochasticity in chemical reactions and diffusion of molecules can have significant effects on the outcomes of intracellular processes, particularly given the low copy numbers of many proteins and mRNAs present in a cell. For such molecular species, the number and locations of molecules can provide a more accurate and detailed description than local concentration. In addition to diffusion, drift in the movements of molecules can play a key role in the dynamics of intracellular processes, and can often be modeled as arising from potential fields. Examples of sources of drift include active transport, variations in chemical potential, material heterogeneities in the cytoplasm, and local interactions with subcellular structures. This dissertation presents a new numerical method for simulating the stochastically varying numbers and locations of molecular species undergoing chemical reactions and drift-diffusion. The method combines elements of the First-Passage Kinetic Monte Carlo (FPKMC) method for reaction-diffusion systems and the Wang—Peskin—Elston lattice discretization of the Fokker—Planck equation that describes drift-diffusion processes in which the drift arises from potential fields. In the FPKMC method, each molecule is enclosed within a "protective domain," either by itself or with a small number of other molecules. To sample when a molecule leaves its protective domain or a reaction occurs, the original FPKMC method relies on analytic solutions of one- and two-body diffusion equations within the protective domains, and therefore cannot be used in situations with non-constant drift. To allow for such drift in our new method (hereafter Dynamic Lattice FPKMC or DL-FPKMC), each molecule undergoes a continuous-time random walk on a lattice within its protective domain, and the lattices change adaptively over time. One of the most commonly used spatial models for stochastic reaction-diffusion systems is the Smoluchowski diffusion-limited reaction (SDLR) model. The DL-FPKMC method generates convergent realizations of an extension of the SDLR model that includes drift from potentials. We present detailed numerical results demonstrating the convergence and accuracy of our method for various types of potentials (smooth, discontinuous, and constant). We also present several illustrative applications of DL-FPKMC, including examples motivated by cell biology.

Earthworm-microbial interactions with emphasis on the passage effects of Eisenia spp. on microbial community were investigated. The study was focused on earthworm potential to regulate functional microbiota in cattle-impacted soils. Microbial communities were studied through a combination of polar lipid analyses, molecular, and culturing methods.

Cryptosporidium is a genus of apicomplexan unicellular epicellular parasite with worldwide distribution causing watery diarrhea in humans and animals. The life cycle is completed in one host, where Cryptosporidium parasitizing epithelial cells of gastrointestinal tract and in birds can cause disease of respiratory or urogenital tract. Course of disease depends on condition of immune system. For immunodeficient individuals could be life threatening. One of problems especially in developing countries is early and correct diagnostic, particularly no effective treatment currently exist. The aim of this thesis was to compare efficiency of immunochromatographic tests in samples stored under different conditions. The comparison of sensitivity and specificity of these tests with molecular and microscopic techniques was also performed. Additionaly, suitability of immunochromatographic tests for detection of active infection during prepatent period was evaluated. The theoretic part includes general information about Cryptosporidium. Its taxonomy, cycle of evolution or transmission and course of disease. Using of immunochromatographic test is also mentioned. No differences in sensitivity of used immunochromatographic tests was observed in this thesis. The detection rate for most of tests was 200 oocyst per sample. The presence of coproantigen is depend upon presence of oocysts in a sample. False negative results of immunochromatographic assays was caused by i) low concentration of oocysts in a sample (sensitivity) or ii) antibodies in used test don´t react with antigen of Cryptosporidium spp. (specificity). Results of this thesis show that combination of immunochromatographic tests and other techniques is convenient. During prepatent period is not possible to detect specific DNA, antigen or oocysts of Cryptosporidium. The active infection could not be distinguish from passage of oocysts using of immunochromatographic assays even if PCR is also used.

O presente estudo é uma análise antropológica sobre as experiências de jovens estudantes estrangeiros que participaram de programa de intercâmbio cultural escolar no RS. Programas com esta finalidade existem há mais de sessenta anos no mundo e há mais de cinquenta no Brasil. Para o programa de intercâmbio ocorrer, vários atores interagem: os jovens estrangeiros (intercambistas), as famílias hospedeiras, as organizações promotoras e as comunidades hospedeiras entre outros. Em vista disso, o universo de pesquisa abrangeu, além dos estudantes estrangeiros; as famílias e escolas gaúchas, participantes do programa; a organização responsável pelo intercâmbio escolhida para esse estudo, e as comunidades gaúchas que receberam esses jovens. Foram realizadas observações participantes e entrevistas com os intercambistas; com as famílias hospedeiras, com estudantes que haviam regressado a seus países de origem após participarem do intercâmbio, com as famílias gaúchas que já os haviam recebido e, também, com as escolas participantes. Os encontros promovidos pela Organização, destinados aos jovens, foram acompanhados pela pesquisadora. Além disso, foram coletados dados em redes sociais com o uso da internet. Através desta etnografia, foi possível perceber diferentes sentidos e significados evocados por esses jovens estrangeiros e pelas famílias gaúchas, o que indicou uma diversidade de motivações e projetos de vida dos diferentes participantes do programa. Essa diversidade, no entanto, convergia para a vivência de uma „experiência‟. Segundo os estudantes estrangeiros, essa experiência significou uma „busca de transformação de si‟, podendo ser entendida, inclusive, como a busca por um ritual de passagem. A Organização, por sua vez, se mostrou disposta a trabalhar a proposta do programa de maneira a proporcionar essa „passagem‟. O estudo revelou, também, o desejo das famílias gaúchas de estabelecer relações afetivas que ultrapassassem as barreiras nacionais e perdurassem após o intercâmbio. Com o retorno dos jovens a seus países, tornou-se evidente que redes de relacionamento entre os participantes da experiência haviam sido construídas, assim como uma rede entre grupo de jovens estrangeiros, e também destes com as famílias e comunidades hospedeiras. O grupo de intercambistas partilhava interesses, estilos de vida e as experiências de intercâmbio seguiram sendo compartilhadas através da internet. / High school intercultural exchange programs exist for over sixty years around the world and in Brazil for more than fifty. In order to make them happen, it is necessary a range of stakeholders, including youngsters, families, promoting institutions, communities, among others. This study is an anthropological analysis of the experiences of high school intercultural exchange programs of young foreigners in Brazil. The research base had families and schools from the state of Rio Grande do Sul, exchange students, the Organization chosen for the study and the community who received these youngsters. During the research, participating observations and interviews were made. The meetings and orientations for the exchange students sponsored by the Organization were monitored, as well as families and students in cities where they were living. Former exchange students who had already returned to their countries of origin were also interviewed, as well as their respective Brazilian families and the participating schools. Data were also collected from social networks through Internet. Based on this ethnography, it was possible to perceive different meanings evoked by these exchange students and by their Brazilian families. We observed that the different participants of the program had a diversity of motives and life projects; however converging on the living of an 'experience'. According to the exchange students studied, this experience came as a search to 'transform themselves' thus it can be even understood as the search for a rite of passage. The Organization also showed to be willing to apply the program proposal so as to provide this 'passage' to the youngsters, which, in turn, requires the need for community networks to provide support to the experience. The study also revealed the desire of the families studied to establish relationships that could go beyond national boundaries continuing after the exchange period. After the exchange students returned to their countries, we observed the construction of relationship networks among the exchange students, as well as a network of people (youngsters and families) who shared the same interests, lifestyles and exchange experiences in different parts of the world through this Organization.