Submitted by Celso Magalhaes (celsomagalhaes@ufrrj.br) on 2017-06-13T13:31:56Z No. of bitstreams: 1 2015 - William Soares Medeiros.pdf: 2112015 bytes, checksum: 79b821090426baeb106b29b980b2ad18 (MD5) / Made available in DSpace on 2017-06-13T13:31:56Z (GMT). No. of bitstreams: 1 2015 - William Soares Medeiros.pdf: 2112015 bytes, checksum: 79b821090426baeb106b29b980b2ad18 (MD5) Previous issue date: 2015-07-31 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / Dermatobia hominis (Linneaus Jr., 1781) (Diptera, Cuterebridae), popularly known in English as the Human Botfly or Warble fly, the only species of this genus and endemic to the neotropical region, is a holometabolous insect with an independent phase of life in its adult form and an obligatory parasitic phase in its larval form. In its parasitic phase, the larva is the cause of furuncular myiasis occurring in a large variety of endothermic animals, with most frequent occurrence in cattle, dogs and humans. The lack of information concerning dermatobiosis creates difficulties in its diagnosis. By means of a systematic review of the literature on the subject, it can be verified that this fly shows versatility in its phoresis and has a vast list of phoretic records. Field studies are restricted to observation of its larval form, because its adult form is difficult to observe, making this a rare event. With the intention of evaluating and comparing fluctuation in the population of D. hominis, searching for correlations between the incidence of Botfly larval infestations and climatic factors and their distribution on the body surface of cattle, two areas of study were selected, in which field collections were carried out twice monthly for counting the number of larvae in the herds. Discrepancies were discovered in the average number of larval nodes in cattle between these areas of study. These nodules showed variation in their bodily distribution on the cattle, with a higher incidence in the anterior region, compromising the quality of the animals? skins for economic purposes. In one of the areas, there was a correlation between the average number of larvae and the temperature and precipitation. These climatic factors are related to edaphic characteristics, influencing the penetration of the L3 larvae and the pupal period. For a greater understanding of the dynamics and fluctuations in the population of D. hominis in these areas, ample monitoring is needed to determine if the results encountered in this study are atypical or influenced by local characteristics. Currently, the demand for research is for methods of controlling the dermatobiosis, with emphasis on integrated plague management. Other deficiencies include following the Botfly?s complete life cycle in the laboratory and understanding certain peculiar adaptations, such as atrophied oral apparatus / A Dermatobia hominis (Linneaus Jr., 1781) (Diptera, Cuterebridae), popularmente conhecida como mosca do berne, ?nica esp?cie do g?nero e end?mica da regi?o Neotropical, ? um inseto holomet?bolo com uma fase de vida livre na sua forma adulta e uma fase parasit?ria obrigat?ria em sua forma larval. Em sua fase parasit?ria, a larva ? causadora da mi?ase furuncular ocorrendo em uma grande variedade de animais endot?rmicos, com ocorr?ncia mais frequente em bovinos, c?es e no homem. A falta de informa??o sobre a dermatobiose gera dificuldade em seu diagn?stico. Atrav?s de uma revis?o sistem?tica da literatura sobre o assunto, verifica-se que a mosca apresenta versatilidade para a foresia e conta com vasta lista de registros de for?ticos. Os estudos em campo se restringem a observa??es sobre sua forma larval, pois sua forma adulta ? de dif?cil observa??o tornando este evento raro. Visando avaliar e comparar a frequ?ncia populacional de D. hominis, buscando correla??o entre a incid?ncia do berne e fatores clim?ticos e a sua distribui??o na superf?cie corporal de bovinos, foram selecionadas duas ?reas de estudo, as quais foram realizadas coleta de campo quinzenalmente para o levantamento do n?mero de bernes no rebanho. Foram encontradas diverg?ncias no n?mero m?dio de n?dulos de berne em bovinos entre as ?reas de estudo. Os n?dulos apresentaram varia??o na distribui??o corporal dos bovinos, tendo maior incid?ncia na regi?o anterior, comprometendo a qualidade da pele do animal para fins econ?micos. Em uma das ?reas houve correla??o entre o n?mero m?dio de bernes e a temperatura e precipita??o. Esses fatores clim?ticos est?o relacionados ?s caracter?sticas ed?ficas, influenciando a penetra??o das larvas L3 e o per?odo pupal. Para o maior entendimento da din?mica e frequ?ncia populacional da D. hominis nessas ?reas, h? necessidade de amplo monitoramento para averiguar se os resultados encontrados neste estudo s?o at?picos ou influenciados por caracter?sticas locais. Atualmente a demanda de pesquisa est? em m?todos para controle da dermatobiose, com destaque para o manejo integrado de pragas. Outras lacunas est?o na realiza??o de seu ciclo completo em laborat?rio e compreens?o de adapta??es peculiares, tais como aparelho bucal atrofiado.

Orientador: Antonia Cecília Zacagnini Amaral / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-26T06:06:23Z (GMT). No. of bitstreams: 1 Daolio_RachelFurioso_M.pdf: 2566347 bytes, checksum: 646f1db51330af90d55b405f39cb815b (MD5) Previous issue date: 2014 / Resumo: Os polidorídeos são poliquetas da família Spionidae cuja característica principal é a presença de cerdas em forma de ganchos no 5° setígero. Algumas espécies habitam fundos não consolidados, enquanto que outras, como Polydora neocaeca, habitam substratos consolidados, podendo ou não perfurar estruturas calcárias como corais e conchas de moluscos. A forma de perfuração é pouco compreendida, existindo hipóteses de que seja mecânica, química ou a combinação desses processos. A infestação raramente causa a morte direta dos hospedeiros, porém os torna suscetíveis a outros parasitas e doenças. Por essa razão, os polidorídeos são considerados pestes pela indústria de moluscos. Polydora neocaeca parasita o mexilhão Mytella charruana que pode ser encontrado formando bancos na região entremarés de praias abrigadas. Dois bancos de M. charruana localizados nas praias do Camaroeiro e da Cidade na enseada de Caraguatatuba (Litoral Norte do Estado de São Paulo) foram estudados de março de 2006 a março de 2007. Na porção central de cada banco, foram traçados transectos perpendiculares à linha d¿água, sendo sorteado mensalmente um de cada banco para amostragem. Em cada transecto, substratos de três níveis foram coletados com o auxílio de um delimitador de 0,04 m² para a triagem dos mitilídeos e dos polidorídeos. O presente trabalho teve como objetivo (1) caracterizar as duas áreas de estudo quanto a variáveis ambientais (perfil praial, salinidade da água intersticial, temperaturas do ar e do sedimento e granulometria, teor de calcário e conteúdo de matéria orgânica do sedimento) e estrutura (densidade de M. charruana); (2) analisar a morfometria dos dois grupos de P. neocaeca (do Camaroeiro e da Cidade); e (3) avaliar a biologia populacional destes, incluindo sua dinâmica, estrutura etária, recrutamento, crescimento e mortalidade. O perfil da praia do Camaroeiro permitiu classificá-la como de dissipativa a intermediária e, o da Cidade, como intermediária do tipo terraço de baixamar. A densidade de M. charruana, o conteúdo médio de calcário e a fração do sedimento de silte + argila foram maiores no banco da Cidade. As demais variáveis foram semelhantes entre os dois bancos. O único modelo de crescimento alométrico que apresentou um bom suporte ás medidas morfométricas dos dois grupos de P. neocaeca foi o modelo de dois segmentos. Esses polidorídeos apresentaram alometria negativa, ou seja, ao longo do seu desenvolvimento o aumento no número total de setígeros é proporcionalmente menor do que o aumento no comprimento total. A largura do setígero 5 foi selecionada como a medida parcial mais adequada para a estimativa do tamanho total dos indivíduos. Apesar da diferença estrutural entre os bancos, P. neocaeca apresentou padrão temporal de recrutamento e parâmetros de crescimento semelhantes entre os dois grupos. Isso sugere que há fluxo gênico (via dispersão) entre eles, tratando-se de uma única população. Porém, a abundância, o tamanho médio da largura do setígero 5 e a longevidade desses polidorídeos foram maiores na Cidade, enquanto que sua mortalidade foi maior no Camaroeiro. Essas diferenças estão mais relacionadas á densidade de mitilídeos hospedeiros (maior no banco da Cidade) do que ás demais variáveis analisadas / Abstract: Polydorids are polychaetes from the Spionidae family whose main characteristic is the presence of modified hooks on the 5th setiger. Some species inhabit soft substrata, while others, such as Polydora neocaeca, inhabit hard substrata, boring or not self-excavated burrows on calcareous structures such as corals and mollusk shells. The boring mechanism is poorly understood and might be mechanical, chemical or the combination of these processes. The infestation rarely causes the direct death of hosts, but makes them susceptible to other parasites and diseases. Thus polydorids are considered as pests by the fishery industry. Polydora neocaeca parasites the Mytella charruana mussel, which can be found forming beds on the intertidal region of sheltered beaches. Two M. charruana beds located at the Camaroeiro and the Cidade beaches from Caraguatatuba Bay (North Coast of São Paulo State) were studied from March 2006 to March 2007. On the central portion of each mussel bed, transects were delimited perpendicular to the waterline, with one from each mussel bed being monthly sampled. On each transect, three levels of substrata were collected with a 0.04 m² corer in order to sample the mytilid and the polydorid individuals. This study aimed to (1) characterize the two sites regarding their environmental variables (beach slope, interstitial water salinity, air and sediment temperatures, and sediment granulometry, calcareous content and organic matter) and structure (M. charruana density); (2) analyze the morphometrics of the two groups of P. neocaeca (Camaroeiro and Cidade); and (3) assess the population biology of these groups, including their dynamics, size structure, recruitment, growth and mortality. The Camaroeiro beach slope enabled its classification as a dissipative to intermediate beach, and the Cidade one, as a low-tide terrace intermediate beach. The M. charruana density, the mean calcareous content, and the silt + clay sediment fraction were higher at the Cidade mussel bed. The other variables were similar between the two beds. The only allometric growth model that showed good support as to the morphometric measures of both P. neocaeca groups was the two segments model. These polydorids showed negative alometry, which indicates that, along their development, the total number of setigers increase is proportionately smaller than the total length increase. The width of the setiger 5 was selected as the most appropriate partial measure for estimating the individuals total size. Despite the structural difference between the mussel beds, P. neocaeca presented similar recruitment temporal pattern and growth parameters between the two groups. This suggests that there is a gene flow (by dispersal) between them, which constitute a single population. However, the abundance, the mean width of the setiger 5 and the longevity of these polydorids were higher at Cidade, whereas their mortality was higher at Camaroeiro. These differences are more related to the host density (higher at the Cidade mussel bed) than to the other analyzed variables / Mestrado / Ecologia / Mestra em Ecologia

Orientador: Wesley Rodrigues Silva / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-22T17:36:58Z (GMT). No. of bitstreams: 1 Baumgarten_LeandroClaudio_D.pdf: 2505570 bytes, checksum: 605fa921efad6929c5d1ccf17fe35faa (MD5) Previous issue date: 2007 / Resumo: Aves de rapina são pouco estudadas no Brasil e existem poucas informações sobre os padrões de dinâmica populacional das espécies que ocorrem no país, assim como os fatores que os influenciam. Com o objetivo de caracterizar a dinâmica populacional de rapineiros e como ela é influenciada pela abundância de presas, foi realizado um acompanhamento de 36 meses das populações de aves de rapina e pequenos mamíferos no Parque Nacional das Emas (Mineiros-GO). Além disto, foram coletadas informações sobre os padrões de atividade das presas para caracterizar mais claramente sua disponibilidade para predadores. A amostragem das presas foi realizada em nove estações de captura, cada uma com 24 armadilhas "pitfall" e a abundância de rapineiros foi a avaliada por censo de carro. Foram realizadas 12 coletas de dados com intervalos de dois meses entre si. Não foi verificada variação de abundância em nenhuma das espécies de aves de rapina entre anos, ao longo do estudo, no entanto a maioria delas apresentou grandes flutuações sazonais. Os dados obtidos sugerem que estas variações foram causadas principalmente pela movimentação das aves para dentro e fora da reserva. Para os pequenos mamíferos não foi encontrada variação sazonal significativa, mas durante 2001 foi registrado um grande aumento na abundância das três espécies mais comuns. A espécie de roedor mais abundante, Bolomys lasiurus, apresentou dinâmicas diferenciadas entre algumas estações de captura. Apesar da considerável variação de abundância das presas não foi detectada uma resposta numérica das aves de rapina no PARNA das Emas ao longo dos três anos de estudo. A comparação deste estudo com outros disponíveis na literatura, sugere que amostragens feitas em áreas mais extensas teriam dificuldade em detectar respostas predatórias, porque não seriam capazes de discriminar pequenas concentrações locais das aves de rapina causadas por aumentos pontuais de disponibilidade de presas / Abstract: Birds of prey are poorly studied in Brazil, and there is few information on patterns of population dynamics of species occurring in the country, as well as factor influencing them. We sample bird of prey and small mammals populations for 36 months aiming to describe raptor population dynamics and how it is influenced by prey abundance in Emas National Park (Mineiros - GO). Furthermore, we collect data on prey daily activity patterns to evaluate their availability for predators. Prey monitoring was performed in nine trapping sites, each one with 24 pitfall traps, raptor sampling was evaluated using car census. We did 12 one-month fieldtrips with two months apart. We did not detected abundance variation among years for any raptor species, although most of them showed seasonal fluctuations. Data gathered suggests these population changes were caused mostly by movements to and from the reserve. We did not find any seasonal fluctuations of small mammals, but we record a major increase of abundance for three of the commonest species. The most abundant species, Bolomys lasiurus, showed different population dynamics among trapping sites. We did no detected numerical response of birds of prey in Emas National Park along this three-year sampling. We compare these data with other studies available, and we suggest that sampling performed in larger areas would hardly detect predatory responses, because it would not be able to discern small local concentrations of raptors caused by increase in prey availability / Doutorado / Ecologia / Doutor em Biologia

Orientador: Antonio Carlos Pereira / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba / Made available in DSpace on 2018-08-24T00:18:46Z (GMT). No. of bitstreams: 1 Lourenco_EloisiodoCarmo_D.pdf: 1076909 bytes, checksum: 5f15f1bf16a0c3ca92dcc88772b0f283 (MD5) Previous issue date: 2013 / Resumo: Nas últimas duas décadas vêm sendo observadas mudanças nos indicadores de morbi-mortalidade no Brasil. Trata-se de um período no qual, além do advento do Sistema Único de Saúde e da Estratégia de Saúde da Família, relevantes transformações ocorreram no cenário macro-econômico e social do país. Para a consolidação de tais mudanças positivas, é necessário, sobretudo, que se compreendam os fatores que interferiram nas mesmas, a fim de se organizar os serviços de saúde coerentemente com o seu enfrentamento. Assim, o presente estudo analisou todos os municípios do Estado de São Paulo no período de 1998 a 2008, considerando três tendências epidemiológicas distintas como variáveis dependentes: percentual de nascidos vivos de mães sem pré-natal, tendência da morbidade hospitalar adulta por Insuficiência cardíaca (IC) e Acidente vascular cerebral (AVC) e mortalidade infantil, testadas com seis variáveis independentes de correção: produto interno bruto (PIB) per capta, cobertura da Estratégia de Saúde da Família (ESF), porte populacional dos municípios, cobertura por PACS (Programa de Agentes Comunitários de Saúde), IPRS (Índice Paulista de Responsabilidade Social) e renda per capta, através de modelos de medidas repetidas no tempo. Os resultados do presente estudo apresentam-se nessa tese na forma de 03 artigos e os principais resultados são: a) houve diminuição significativa do percentual de nascidos vivos de mães sem pré-natal no período estudado, havendo uma correlação negativa entre a mesma e as variáveis: PIB per capta, cobertura da Estratégia de Saúde da Família e porte populacional; b) houve uma tendência de queda da morbidade hospitalar adulta por IC e por AVC, significativamente influenciada pelo PIB per capta; c) a queda da mortalidade infantil no período analisado foi influenciada pelo crescimento do PIB per capita e pelo modelo de atenção Saúde da Família. Concluiu-se que as tendências epidemiológicas verificadas no decorrer do tempo requerem análises que levem em conta, sempre, as variáveis contextuais, as quais podem, tanto gerar as referidas mudanças, quanto nortear a organização dos serviços / Abstract: In the last two decades have been observed changes in indicators of morbidity and mortality in Brazil. It is a period in which, besides the advent of the National Health System and the Family Health Strategy (PSF), relevant changes occurred in the macro-economic and social development. In order to consolidate these positive changes, it is necessary, above all, understand the impact factors, in order to organize health services consistently with your facing. Thus, the present study examined all municipalities in the state of São Paulo in the period 1998-2008, considering three distinct epidemiological trends, using four dependent variables: percentage of live births to mothers without prenatal, trend of hospitalizations for adult heart failure (CI) and stroke (CVA) and infant mortality, and to associate with six independent variables for correction: gross domestic product (GDP) per capita, coverage of the Family Health Strategy (FHS), population size of the municipalities covered by PACS (Program Community Health Workers), IPRS (São Paulo Index of Social Responsibility) and per capita income, through models of repeated measures. The results of this study are presented in this thesis in the form of 03 articles, and the main results are: a) a significant decrease in the percentage of live births to mothers without prenatal care during the study period, and a negative correlation between dependent and variables: GDP per capita, population coverage of PSF and population size, b) there was a downward trend in adult hospital admissions for HF and stroke, significantly influenced by GDP per capita, c) the decline of infant mortality in the analyzed period was influenced by the growth of GDP per capita and the model of care Family Health. It was concluded that epidemiological trends observed over time require analyzes that take into account where the contextual variables, which can both generate these changes, the guide service organization / Doutorado / Saude Coletiva / Doutor em Odontologia

Orientador: Antonia Cecília Zacagnini Amaral / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-20T07:27:07Z (GMT). No. of bitstreams: 1 Nagai_MicaelEiji_M.pdf: 3849182 bytes, checksum: 92cd2402854619961d0d6bfedddb7009 (MD5) Previous issue date: 2012 / Resumo: O estudo do silídeo Exogone (Exogone) breviantennata foi realizado em dois bancos de Mytella charruana (sururu) nas praias do Camaroeiro e da Cidade, localizadas na enseada de Caraguatatuba, Litoral Norte de São Paulo. Para caracterizar as áreas de estudo foram realizadas amostragens mensais, entre fevereiro de 2006 e fevereiro de 2007, no Camaroeiro, e entre abril de 2006 e março de 2007, na Cidade, e avaliados os parâmetros ambientais: perfil praial, granulometria, temperaturas do ar e do sedimento, salinidade da água intersticial e teores de calcário e matéria orgânica. O perfil praial do Camaroeiro apresentou uma declividade acentuada desde o supralitoral, terminando em uma pequena planície no nível d'água; a praia da Cidade apresentou um extenso platô na região superior e em seguida um declive contínuo. A composição granulométrica dos dois bancos foi semelhante, com predominância de areia fina, pobre a moderadamente selecionada. As temperaturas médias do ar e do sedimento no banco do Camaroeiro foram de 23,08°C e 23,73°C, respectivamente, e na Cidade de 22,55°C e 23,98°C, respectivamente. As áreas médias dos bancos do Camaroeiro e da Cidade foram de 586,73 m2 e de 464,48 m2, respectivamente. Em ambos os bancos houve uma diminuição gradual na área. No banco do Camaroeiro a salinidade da água intersticial variou de 22 a 34, enquanto na Cidade de 25 a 34. O teor médio de calcário no banco do Camaroeiro apresentou uma variação de 3,74 a 11,99%, já na Cidade foi de 5,55 a 14,30%. O teor médio de matéria orgânica apresentou valor mínimo de 0,74 % e máximo de 8,40% no Camaroeiro, enquanto na Cidade foi de 2,62% e 7,98% / Abstract: The study of the syllid Exogone (Exogone) breviantennata was conducted in two soft bottom beds of the mytilid Mytella charruana at Camaroeiro and Cidade beaches, located on the northern coast of São Paulo. To characterize the study areas, samples were taken monthly between february 2006 and february 2007 at Camaroeiro, and between april 2006 and april 2007 at Cidade, where the following environmental parameters were analyzed: beach slope, granulometry, air and sediment temperatures, interstitial salinity and levels of calcareous and organic matter. The beach slope of Camaroeiro showed a sharp decline from the supralitoral, ending with a narrow flat at water level, with processes of deposition and erosion; the Cidade beach presented an extensive plateau at the upper region and then a sharp decline, with erosion as the main process. The granulometric composition of the two beds was very similar, with a predominance of fine sand, with low to moderate selection. The average air and sediment temperatures at Camaroeiro were 23.08°C and 23.73°C, respectively, while in the Cidade was 22.55°C and 23.98°C, respectively. The mean areas of the Camaroeiro and Cidade beds were 586.73 m² and 464.48 m², respectively. On both beds there were gradual decreases in these areas. At Camaroeiro the interstitial salinity ranged from 22 to 34, while at Cidade from 25 to 34. The average percentage of calcareous on the Camaroeiro bed showed a variation from 3.74 to 11.99%, while on the Cidade bed it ranged from 5.55 to 14.30%. The average percentage of organic matter presented minimum and maximum of 0.74% to 8.40% at Camaroeiro, while the Cidade bed presented 2.62% and 7.98% / Mestrado / Ecologia / Mestre em Ecologia

Ips typographus est le principal ravageur de l'épicéa en Europe, s’attaquant en masse aux arbres vivants en période d’épidémie, par le biais d’une communication chimique. Comme de nombreuses autres espèces de scolytes « agressives », le typographe se reproduit uniquement sur des arbres affaiblis ou des chablis en périodes d’endémie, quand les densités de population ne sont pas suffisantes pour surmonter les défenses des arbres vivants. Ces ressources sont en général présentées dans la littérature comme étant dispersées et imprédictibles dans le temps et l’espace. De plus, ces ressources affaiblies sont sans doute disponibles pour de nombreuses espèces compétitrices. Ces caractéristiques imposent des contraintes importantes sur la dynamique de population et l’écologie du typographe et principalement sur sa stratégie de prospection. Cela dit, cette espèce et ces questions sont très peu étudiées en période d’endémie.Durant ma thèse de doctorat, je me suis attelé à tout d’abord caractériser les facteurs déterminant la distribution spatio-temporelle des chablis, qui va influencer l’évolution des stratégies de dispersion. Cet aspect s’est prolongé par l’étude de la « durée de vie » des chablis, c’est-à-dire la période durant laquelle ils sont colonisables par les scolytes après déracinement. Cet aspect a été mis en parallèle avec les capacités de défenses de ces mêmes arbres et leurs effets sur la sélection de l’hôte et le succès des scolytes. Enfin, les données obtenues par ces études ont été intégrées à un modèle spatialement explicite visant à valider les hypothèses comportementales relatives à la prospection pour les ressources chez le typographe, à savoir une dispersion aléatoire à grande distance suivie d’un recrutement au niveau des ressources nouvellement trouvées.Les résultats obtenus au cours de cette thèse confirment l’importance de la prospection sociale et de l’agrégation dans la découverte et l’exploitation de ressources dispersées, dont la dégradation intrinsèque représente une faible contrainte temporelle. Ces comportements ont sans doute été développés chez des insectes saproxyliques en raison de l’avantage qu’ils apportent en termes de découverte de ressources. Dans un second temps, ces comportements auraient pu permettre l'attaque d‘arbres vivants, notamment en réponse à une pression de compétition inter-spécifique importante sur des ressources peu défendues. / Option Biologie des organismes du Doctorat en Sciences / info:eu-repo/semantics/nonPublished

Nous présentons deux problèmes de biologie faisant appel à un traitement de données et des modèles issus de la physique statistique : la dynamique des populations en immunologie et la régulation génétique dans le développement embryonnaire. En immunologie, nous étudions le problème de la sélection somatique dans le système immunitaire adaptatif: la sélection cellulaire et la compétition qui s’y opèrent, constituant un système quasi Darwinien au sein de l’organisme. Dans un premier temps, nous considérons différentes hypothèses surla dynamique sélective : signaux déclenchant la division ou la mort cellulaire par liaison antigénique ou par cytokines, paramètres dynamiques de division, mort et fluctuations environnementales. Nous explorons leur influence sur la taille des clones dont la distribution à queue lourde a été observée à travers les espèces et les types de cellules. Deux familles de modèles émergent : un premier dans lequel le bruit est cohérent à l’échelle du clone et un second dans lequel le bruit varie de cellule à cellule. Nous montrons dans quelle mesure la distribution de taille de clones permet de déterminer le meilleur modèle et relions la forme de la distribution ainsi que l’exposant apparent de la loi de puissance aux paramètres biologiques. Dans un second temps, nous explorons les caractéristiques du réseau complexe et aléatoire formé par les clones et les antigènes : dimension, adjacence, dynamique. Nous nous intéressons à l’effet de la sélection dans le temps et à la vitesse d’évolution des clones.La deuxième partie de cette thèse est consacrée au développement embryonnaire. Dans l’embryon, il est essentiel pour le noyau de déterminer sa position avec une grande précision pour orienter la différentiation et construire un organisme structuré viable. Cette information positionnelle est acquise, transmise et conservée par la diffusion de protéines et l’activa- tion de circuits génétiques.Plus précisément, la formation de l’axe antéropostérieur chez la Drosophile est déterminée entre autres par l’activation du gène hunchback par la protéine Bicoid. Nous analysons des données issues d’expériences d’imagerie fluorescente dynamique dans les premiers cycles cellulaires de l’embryon. Nous construisons un modèle spécifique permettant d’analyser la fonction d’autocorrélation des traces temporelles de fluorescence qui prend en compte toutes les difficultés biologiques et expérimentales (bruit, calibration traces courtes, structure du gène artificiel) pour extraire les paramètre dynamiques d’activation de hunchback. Nous examinons différentes dynamiques potentielles (poisonnienne, markovienne ou non markovienne) et leur implication pour l’information dont la cellule dispose sur sa position ainsi que la précision de la lecture du gradient de Bicoid. / This work presents two problems of biology requiring data analysis and models from statistical mechanics: population dynamics in immunology and gene regulation in embryo development. In immunology I study the problem of somatic evolution in the adaptive immune system: selection of and competition among cells that form a close-to-Darwinian system within one individual. First, I consider different potential hypotheses for selective dynamics: division and death signals through antigen binding or cytokines, dynamical parameters for division, death and fluctuations of the environment. I explore their impact on clone sizes. Experimentally, these clone sizes show heavy tail distributions for different species and differentpools of cells. Two families of models emerge: models where noise is consistent at the level of the clone and models where it varies from cell to cell. I show how clone size distributions help discriminate between these models and relate the shape of the distribution and the exponent of the power law to biological parameters. Second, I explore the specifics of the complex stochastic network of clones and antigens: its dimensionality, connectivity and dynamics. I study the effect of selection at different time scales and the speed of evolution of the clones. The second part of this dissertation concerns embryo development. In the fly embryo, it is crucial that nuclei can evaluate their position within the organism accurately to determine cell fate and build a healthy organism. This positional information is obtained, transferred, and maintained through diffusion of proteins and activation of genetic networks. More specifically, the patterning of the antero-posterior axis in drosophila requires the hunchback gene, activated by the Bicoid protein. I analyze data from fluorescent live imaging in the early cell cycles of the embryo. I build a tailor-made model to analyze autocorrelation functions of fluorescence time traces overcoming all biological and experimental challenges (noise, calibration, short traces, transgene construct) to extract the parameters of hunchback activation. I examine several potential types of dynamics for gene switiching (Poisson, Markovian or non-Markovian) and predict their impact on positional information and the accuracy of bicoid gradient readout.

This study analyzes data acquired in French Polynesia in the Pacific and The Bahamas (Atlantic), both oceans affected by recent, well documented and sequential disturbances. For the purposes of this study, a disturbance is defined as a perturbation of environmental, physical or biological conditions that causes a distinct change in the ecosystem. After several decades of coral bleaching events, biological change, and anthropogenic impacts, rapid assessments of the coral community were accomplished by collecting photo-transects across the reefs to extract size structure of the corals, percent live tissue cover and perform a faunal evaluation. Cluster analyses and spatial autocorrelation tests were done to examine the community structure and dynamics at both locations. All multivariate analyses pointed to a disturbed ecosystem and the lack of spatial correlation indicated the impact of a local disturbance over that of a regional event. In assessing the spatial coral community structure, different responses to large versus small scales of disturbance were found. This emphasizes the importance of tailoring management of coral reefs to specific impacts. These two distinct regions were shown to have correlated spatial response patterns to sequential disturbances, supporting the idea of community pattern signatures for different scales of disturbance and the need for an adjustment in management protocols.

Abstract Relationships between predators and prey may affect population dynamics of both parties. Predators may also serve as a link between populations of different prey, e.g., small game and small mammals. I used available data on the diet and reproduction of birds of prey (mainly common buzzards Buteo buteo and goshawks Accipiter gentilis) and video surveillance of their nests, as well as multiannual data on numbers of grouse and small mammals for studying food habits and population dynamics of raptors and their links with population fluctuations of voles and grouse (capercaillie Tetrao urogallus, black grouse Tetrao tetrix and hazel grouse Bonasa bonasia) in western Finland during 1980–1990s when grouse and vole numbers fluctuated in regular cycles. Microtus voles were the main prey of the buzzards which partly switched their diet to small game (juvenile grouse and hares) in years when vole numbers declined. The nesting rate of buzzards also correlated with vole abundance, but the productivity rate and brood size tended to lag behind the vole cycle. This mismatch between the buzzards' functional and numerical responses resulted in a fairly small impact of buzzards on juvenile grouse, which did not correlate with vole density. The productivity of goshawks followed the fluctuations of grouse density closely whereas the occupancy rate of goshawk territories did so with a two-year lag. The annual numerical ratio of goshawk to grouse was inversely related to grouse density, suggesting that this predator may be a destabilising factor for grouse population dynamics. However, the goshawks' kill rate of grouse showed no clear relations to grouse density. In June–July, these birds of prey (including hen harriers Circus cyaneus) usually killed a relatively small number of grouse chicks. Losses to raptors constituted up to one quarter of grouse juvenile mortality during the two months. We did not find a strong effect of avian predators on grouse juvenile mortality. In boreal forests, predators and other factors of grouse mortality do not operate as one, and there is probably no single factor responsible for the reproductive success of grouse.

Matrix population models are discrete in both time and state-space, where a matrix with density-dependent entries is used to project a population vector of a stage-structured population from one time to the next. Such models are useful for modeling populations with discrete categorizations (e.g. developmental cycles, communities of multiple species, differing sizes, etc.). We present a general matrix model of two interacting populations where one (the resident) has a stable cycle, and we analyze when the other population (the invader) can successfully invade. Specifically, we study the local bifurcations of coexistence cycles as the resident cycle destabilizes, where a cycle of length 1 corresponds to an equilibrium. We make no assumptions on the types of interactions between the populations or on the population structure of the resident; we consider when the invader's projection matrix is primitive or imprimitive and 2x2. The simplest biological scenarios for such structures are an iteroparous invader and a two-stage semelparous invader. When the invader has a primitive projection matrix, coexistence cycles (of the same period as the resident cycle) bifurcate from the resident-cycle. When the invader has an imprimitive two-stage projection matrix, two types of coexistence cycles bifurcate from the resident-cycle: cycles of the same period and cycles of double the period. In both the primitive and imprimitive cases, we provide diagnostic quantities to determine the direction of bifurcation and the stability of the bifurcating cycles. Because we only perform a local stability analysis, the only successful invasion provided by our results is through stable coexistence cycles. As we show in some simple examples, however, the invader may persist when the coexistence cycles are unstable through competitive exclusion where the branch of bifurcating cycles connects to a branch of invader attractors and creates a multi-attractor scenario known as a strong Allee effect.