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Mossadegh, Rashti Noushin. "Ontogeny of testicular macrophages, the guardians of fertility." Thesis, Aix-Marseille, 2018. http://www.theses.fr/2018AIXM0141/document.
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Les macrophages sont des cellules de l’immunité innée et sont localisés dans la majorité des organes du corps, présentant des fonctions spécifiques dépendant de leur lieu de résidence.Les macrophages d’origine embryonnaire sont la source majeure des macrophages tissulaires et sont capables de se maintenir à long terme dans la plupart des organes adultes.Cependant, il reste certains organes comme le testicule, où l’origine des macrophages n’est pas clairement déterminée. Le testicule est considéré comme un organe immuno-privilégié et a cette nécessité de protéger de tous contacts les spermatozoïdes des cellules immunitaires, qui pourraient induire une auto-immunité.Les macrophages testiculaires (tMφ) contribuent à maintenir ce statut d’organe immuno-privilégié en produisant des cytokines immunosuppressives. Pour ces raisons, les tMφ peuvent être considérés comme des “ gardiens de la fertilité”. Dans les testicules adultes, deux différentes populations de macrophages, nommées interstitielles et péritubulaires, ont été identifiées en se basant sur leurs morphologies et localisations distinctes, mais leur origine et leur mode de développement et de maintenance restent encore inconnus. En combinant des méthodes de traçage cellulaire et la mise au point d’un modèle de transfert adoptif dans des souriceaux, j’ai démontré que les macrophages d’origine embryonnaire contribuaient exclusivement à la population de tMφ interstitielle dès la naissance et que les tMφ péritubulaires proviennent exclusivement de la moelle osseuse. Après avoir caractérisé les tMφ, mes prochaines investigations se porteront sur l’étude des fonctions de chacune de ces deux populationsMacrophages are innate immune cells residing in most of the organs of the body and ensure proper organ function. Traditionally, it has been known that macrophages can be derived from HSC progenitors in the bone-marrow (BM), but technology using fate-mapping tools has revealed that macrophages can already be generated from embryonic progenitors. Embryo-derived macrophages are a major source of tissue-resident macrophages and can self-maintain during adulthood. The origin of resident macrophages in the testis, however, so far has not been well studied.Importantly, the testis is considered as an immune-privileged organ by protecting the highly immunogenic spermatozoa sequestrated in the seminiferous tubules from the entrance of immune cells. In the adult testis, macrophages participate in the creation of an immune suppressive microenvironment preventing auto-immune attack. Therefore, testicular macrophages tMφ could be considered as the guardians of fertility. Recently,two different macrophage populations have been identified in the adult testis, called interstitial and peritubular, based on their distinct localization and morphology,but their developmental origin and homeostatic maintenance were unknown.Combining the genetic lineage tracing and the neonatal adoptive transfer model, I could demonstrate that the embryo-derived macrophages give rise exclusively to interstitial tMφ. Peritubular tMφ, however, only emerge postnatally from BM-derived progenitors. .My findings provide framework for future investigations into the distinct functions of these two tMφ populations in establishment of immune-privilege as well as the support of spermatogenesis and male hormone production
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Martins, Bárbara Araújo. "Osteologia descritiva e desenvolvimento do esqueleto axial e apendicular de Gymnocorymbus ternetzi (Boulenger,1895) (Characiformes Characidae) /." Botucatu, 2016. http://hdl.handle.net/11449/141890.
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Orientador: Ricardo Cardoso BenineResumo: O gênero Gymnocorymbus Eigenmann 1908, pertencente à família Characidae, se distribui ao longo da Amazônia, Orinoco e Paraguai, e pode ser diagnosticado dos outros pertencentes à família por meio de alguns caracteres específicos para este gênero. Uma espécie importante dentro desse grupo é o Gymnocorymbus ternetzi, também conhecida como tetra negro ou black skirt tetra. Esta espécie vem sendo amplamente utilizada em estudos gerais de biologia, genética e fisiologia, porém apenas recentemente foi alvo de um estudo taxonômico abrangente cujos resultados levaram a necessidade de um maior entendimento dos estados dos caracteres envolvidos. Assim, o objetivo do presente projeto foi de descrever o processo de desenvolvimento ontogenético – dos componentes dos esqueletos axial e apendicular de Gymnocorymbus ternetzi, com ênfase nas características informativas do ponto de vista filogenético, assim como a osteologia de exemplares adultos visando complementar a informação existente e o entendimento das prováveis sinapomorfias previamente propostas. Os espécimes de G. ternetzi utilizados neste estudo foram adquiridos comercialmente e mantidos em tanques comunitários de 300 litros com temperatura de 26 a 28°C e pH entre 6,5 e 6,8. Após a entrada no período reprodutivo, machos e fêmeas foram colocados dois a dois (casais) em aquários de 30 litros, com temperatura em torno de 28°C. Situações para estimular a desova foram simuladas e após a desova os adultos foram retirados... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: The genus Gymnocorymbus Eigenmann 1908, belongs to the Characidae family, is distributed along the Amazon, Orinoco and Paraguay, and can be diagnosed from other belonging to the family through some specific characters for this genus. An important species within this group is the black tetra, also known as black skirt tetra. This species has been widely used in general studies of biology, genetics and physiology, but only recently has undergone a comprehensive taxonomic study whose results have led to the need for greater understanding of the states of the characters involved. The objective of this project was to describe the ontogenetic development process - the components of the axial and appendicular skeletons of Gymnocorymbus ternetzi, with emphasis on informative features of the phylogenetic point of view, as well as the osteology of adult to complement existing information and understanding of the likely synapomorphies previously proposed. The specimens of G. ternetzi used in this study were commercially purchased and kept in community tanks of 300 liters with temperature 26 to 28 ° C and pH between 6.5 and 6.8. After entering the breeding season, males and females were placed in pairs (couples) in aquariums of 30 liters, with temperatures around 28 ° C. Situations to stimulate spawning were simulated and after spawning adults were taken to avoid possible predation of eggs. Our results provide important information on the development of the appendicular and axial skeleto... (Complete abstract click electronic access below)
Mestre
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Hübner, Tom. "Ontogeny in Dysalotosaurus lettowvorbecki." Diss., lmu, 2011. http://nbn-resolving.de/urn:nbn:de:bvb:19-125983.
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Carolan, E. J. "Gap junctions in lymphocyte ontogeny." Thesis, University of Glasgow, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.233181.
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Marsh, Deborah Frances. "The ontogeny of opioid analgesia." Thesis, University College London (University of London), 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.286332.
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Frederickson, Joseph Alexander. "Craniofacial Ontogeny In Centrosaurus apertus." Master's thesis, Temple University Libraries, 2013. http://cdm16002.contentdm.oclc.org/cdm/ref/collection/p245801coll10/id/229570.
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GeologyM.S.
Centrosaurus apertus, a large bodied ceratopsid from the Late Cretaceous of North America, is one of the most common fossils recovered from the Belly River Group of Canada. This fossil record shows a wide diversity in morphology and size, with specimens ranging from putative juveniles to fully-grown individuals. The goal of this study was to reconstruct the ontogenetic changes that occur in the craniofacial skeleton of C. apertus through a quantitative cladistic analysis. Forty-seven cranial specimens were independently coded in separate data matrices for 80 hypothetical multistate growth characters and 130 binary growth characters. Analyses were executed under heuristic searches with all characters unordered and equally weighted. Both analyses yielded the max-limit of 100,000 most parsimonious saved trees and the strict consensus collapsed into large polytomies, so a 50% majority rule consensus was obtained to recover structure in the data. In order to reduce conflict resulting from missing data, fragmentary individuals were removed from the data matrices and the analyses were rerun under a branch and bound search for both multistate and binary data sets. The multistate analysis yielded a single most parsimonious tree, while the binary analysis yielded thirteen equally most parsimonious trees. A strict consensus of the thirteen trees collapsed into a polytomy in the most mature individuals, but the resolved portion is consistent with the tree recovered in the multistate analysis. Among both the complete and the reduced data sets the multistate analyses recovered a shorter tree with a higher consistency index (CI) than the additive binary data sets. The arrangement within the trees show a progression of specimens with a recurved nasal horn in the least mature individuals, followed by specimens with straight nasal horns in relatively more mature individuals, and finally specimens with procurved nasal horns in the most mature individuals. The supraorbital unit, however, shows no consistent pattern of development. The parietal horns develop relatively early, becoming long and curved in some of the least mature skulls. In relatively mature individuals these structures resorb, leaving the horns with a withered appearance. This resorption continues in the most mature individuals until much of the horn is gone. The development of the parietal and nasal horns may represent a heterochronic process (i.e. peramorphosis) in centrosaurine evolution, where juvenile morphology is similar to that of basal neoceratopsians, whereas the adult condition is comparable to that of derived centrosaurines. Bone textural changes were found to be sufficient proxies for relative maturity in individuals that have not reached adult size. Additionally, frill size is congruent with relative maturity status and makes an acceptable proxy for ontogenetic status, especially in smaller individuals. In adult-sized individuals, the fusion of the epoccipitals and the orientation of the nasal horn are the best indicators of relative maturity. There is no clear evidence for sexually specific characters or sexual size dimorphism in C. apertus.
Temple University--Theses
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Xu, Liqun. "Ontogeny of myocardial excitation-contraction coupling." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp03/MQ51512.pdf.
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Acquah, Daniel Kofi. "The ontogeny and epistemology of mentalising." Thesis, University of Nottingham, 2011. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.546587.
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Laumann, Katie May. "Sturgeon (Acipenseridae) phylogeny, biogeography, & ontogeny." W&M ScholarWorks, 2016. https://scholarworks.wm.edu/etd/1539616731.
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Thought of as "ancient" fishes, 25 broadly recognized extant sturgeon species are classified in four genera (Acipenser, Huso, Pseudoscaphirhynchus, and Scaphirhynchus). Molecular and morphological analyses have led to broad but conflicting changes to sturgeon phylogeny. For example, the position of Scaphirhynchus among other sturgeons had been contentious, and various sets of sturgeon species have been proposed to make up the subfamily Husinae. Here, a molecular phylogeny of sturgeons, based on the full mitogenome, is presented. In this phylogeny, Scaphirhynchus is recovered with strong support as basal to the other sturgeons. Huso huso is recovered as basal within a clade containing P. kaufmanni and several species of Acipenser, and is proposed as a new, monotypic subfamily Husinae. This phylogeny is used to examine phylogenetic signal in individual genes and in gene families. The protein coding genes as a unit, and individually, along with 16s rRNA, show phylogenetic signal most similar to that of the full mitogenome. The phylogeny, along with evolutionary relationships of pinnipeds and lampreys, provides the basis for the exploration of sturgeon biogeography. Relationships among geographic areas inhabited by sturgeons are found, finding two sets of related areas- a Pacific area group and an Atlantic group. Relationships of areas within and between these groups reflect area relationships proposed by previous biogeographic and geologic studies. Phylogenetic signal is tested amongst ontogenetic characters, and is recovered in the timing at which larval sturgeon teeth are completely resorbed, indicating that the timing of ontogenetic milestones can carry signal. The phylogeny is used to remove confounding signal from, and investigate correlations among, behavioral and morphological ontogenetic characters. Correlation is found between one pair of characters.
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Fan, Di. "Ontogeny of the peripheral gustatory pathways." Thesis, Paris Sciences et Lettres (ComUE), 2018. http://www.theses.fr/2018PSLEE044.
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La composition chimique des aliments est perçue par les bourgeons du goût et transmise au cerveau postérieur par des nerfs viscérosensoriels particuliers, les nerfs du goût. L’intégrité de ces nerfs est essentielle au maintien des bourgeons du goût chez les animaux adultes. Cependant, leur rôle dans l’ontogénie des bourgeons, chez l’embryon et aux premiers stades postnataux, est controversé and reste non résolu. Dans cette étude, j’ai établi de façon définitive que la formation embryonnaire des bourgeons du goût dépend des nerfs gustatifs chez la souris, unifiant ainsi les mécanismes de maintien/régénération et d’ontogénie de ces organes. En parallèle, j’ai réexaminé la possibilité (jusque-là exclue par d’autres auteurs) d’un rôle du facteur de transcription Foxg1 dans la formation des ganglions sensoriels épibranchiaux. J’ai découvert que Foxg1 est un déterminant des neurones gustatifs dans le ganglion géniculé. Ce nouveau rôle, de pair avec ceux décrits précédemment dans l’épithélium olfactif, la placode otique et la rétine, révèle une cohérence physiologique remarquable des fonctions de Foxg1 (en dehors de son rôle bien établi dans le cortex) en tant que facteur de transcription maître des neurones impliqués dans les « sens spéciaux » : vision, ouïe, odorat et goûtTaste information is received by taste buds and transmitted to the hindbrain by special visceral sensory nerves, the taste nerves. The integrity of taste nerves is essential for the maintenance of taste buds in adult animals. However, a role for taste nerves in the ontogeny of taste buds, in the embryo and at early postnatal stages, has been controversial and is still unresolved. In this study, I establish in a definitive manner that embryonic taste bud formation is nerve-dependent in mouse, thus unifying mechanistically the maintenance/regeneration and ontogeny of these organs. Parallel to this work, I re-examined the possibility (previously excluded by other authors) of a role for the transcription factor Foxg1 in epibranchial ganglion formation. I find that Foxg1 is essential for the differentiation of gustatory neurons in the geniculate ganglion. This novel role, together with previously described ones in the olfactory epithelium, otic placode and retina, unveils a striking physiological coherence of the functions of Foxg1 (outside its well established one in the cortex), as a master transcription factor for neurons involved in “special senses”: vision, hearing, smell and taste
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Villares, Júnior Gilberto Aparecido [UNESP]. "Aspectos morfológicos na ontogenia e relação massa/comprimento de Salminus hilarii Valenciennes, 1850 (Characidae, Salmininae)." Universidade Estadual Paulista (UNESP), 2009. http://hdl.handle.net/11449/99521.
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Neste trabalho foram analisados exemplares da espécie Salminus hilarii com a finalidade de verificar as variações morfológicas que possam ocorrer ao longo da vida do peixe, juntamente com a relação massa-comprimento. Para as análises foram tomadas 19 medidas morfométricas, sendo 17 referentes a S. hilarii e duas para as presas ingeridas. Estas medidas foram utilizadas para os cálculos de três índices e 17 valores relativos de atributos morfológicos. As medidas de S. hilarii foram tomadas a partir de exemplares com uma amplitude de tamanho variando entre 50 a 450 mm no comprimento padrão. Foi feita uma comparação entre indivíduos jovens e adultos, machos e fêmeas, e em diferentes classes de comprimento relacionando tais características morfológicas com as velocidades de corrente dos locais onde vivem e o tamanho das presas ingeridas por essa espécie. As amostras para as análises foram coletadas nas bacias dos rios Sorocaba e complementadas com indivíduos depositados no acervo do Departamento de Zoologia provenientes dos rios Jacaré Pepira, Corumbataí (sub-bacia do Tietê), e Mogi Guaçu (sub-bacia do rio Grande). Na comparação entre machos e fêmeas e entre adultos e imaturos foram analisados somente indivíduos capturados no rio Sorocaba onde foi possível a determinação desses grupos. Esse trabalho mostrou que não houve variações significativas entre as sub-bacias dos rios Tietê e Grande. O mesmo foi observado entre machos e fêmeas, mostrando que não há dimorfismo sexual nas características observadas. Entre os imaturos e adultos, assim como nas diferentes classes de comprimento, nove características morfológicas não mostraram diferenças significativas. Nas demais (onze) apresentaram diferenças significativas entre pelo menos duas classes de comprimento. Complementando, foram observadas correlações significativas entre as velocidades calculadas...
Salminus hilarii specimens were studied using several body measurements and relationships related to their proportions, considering mainly possible ontogenetic changes. Relationships between mass and length were analyzed as well. The usual comparisons made for studies related to distinct species was the subject of the study to compare possible changes occurring during the life of individuals of one species. For this purpose 19 morphometric measurements were obtained, but only 17 were related to individuals of the species e 2 for ingested prey. The S. hilarii measurements used individuals whose standard lengths varied from 50 to 450 mm. This study intended to compare young and adult individuals, as well as males and females. Distinct length classes were established and these data were also used to establish possible relationships between individuals who are usually caught in distinct places of the Sorocaba river, and are submitted to distinct water current effects. Larger individuals use to live in the middle of the river where water flows more rapidly, while the younger ones live near to the river margin or calm waters. Food intake may also suggest some distinct morphological aspects. So, the main organism, when almost intact were also measured. Samples for the analyses were collected at the Sorocaba basin, but were complemented with specimens collectecat the rivers Jacaré-Pepira, Corumbataí (Tietê sub-basin) and Mogi-Guaçu (Rio Grande sub-basin). These specimens are deposited at the Zoology Department (Unesp – Rio Claro). To compare males and females, only fish from the Sorocaba river were considered for analysis. The study permitted to find out that no significant differences exist for fish originated from the Tietê and Rio Grande sub-basins. The same happens for male and female individuals. When immature and adult individuals were compared nine morphological characters... (Complete abstract click electronic access below)
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Sims, Ligia Paulillo. "Aspectos da historia de vida da especie de dossel Savia dictyocarpa Mull. Arg. (Phyllanthaceae) em um fragmento da floresta estacional semidecidua no Municipio de Campinas, SP." [s.n.], 2009. http://repositorio.unicamp.br/jspui/handle/REPOSIP/315871.
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Orientador: Fernando Roberto MartinsDissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia
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Resumo: O presente estudo investigou a estrutura de estádios ontogenéticos e espacial da espécie Savia dictyocarpa (Phyllanthaceae) na Mata Ribeirão Cachoeira, Campinas, SP. Essa espécie dióica é comum ocupante do dossel de florestas estacionais da região sudeste do Brasil e dada sua importância resolveu-se levantar informações sobre sua história de vida. Para tanto foram feitas duas questões centrais: 1) é possível definir os estádios ontogenéticos de S. dictyocarpa a partir da variação morfométrica e arquitetural que ocorre longo da vida da espécie? 2) qual distribuição espacial dos indivíduos ao longo da ontogenia dessa espécie e quais os fatores ambientais que influem na distribuição? Nos 0,5 hectares amostrados encontramos 194 indivíduos distribuídos em 5 estádios ontogenéticos: infantil, jovem, imaturo, adulto e senil. Não encontramos plântulas ou adultos reprodutivos nas parcelas, mas encontramos algumas plântulas. Portanto a definição do estádio plântula foi feita sem considerações sobre caracteres morfométricos. Os frutos encontrados não possuíam sementes, o que pode ser indicativo de ausência de polinização de flores, seja pela baixa freqüência de indivíduos masculinos ou pela ausência de polinizador. O padrão de ramificação apresentado é próprio do modelo arquitetural de Massart, que é característico de espécies bem adaptadas às condições de pouca luz. Os estádios apresentaram diferenças significativas quanto à altura e diâmetro. Jovem e imaturo apresentaram menor aumento em diâmetro por incremento em altura, ocorrendo o inverso com o estádio adulto. O maior investimento em altura durante os estádios iniciais permite que os indivíduos alcancem rapidamente as boas condições de luminosidade próximas ao dossel, em detrimento da estabilidade mecânica. Encontramos que o investimento em altura da copa por unidade de aumento em diâmetro da copa tem tendência de aumentar ao longo da ontogenia, o que denota diferenciação entre estádios para aumento da eficiência na obtenção de luz. A infestação de lianas parece ter efeito sobre desenvolvimento da copa dos indivíduos adultos, pois indivíduos com lianas têm menor investimento em altura da copa. Todos os estádios apresentaram distribuição aleatória no espaço, sendo que imaturo e jovem possuem tendência de ocupar mesmos locais, possivelmente por necessitarem das mesmas condições ambientais para recrutamento e crescimento. Todas as correlações entre estádios e luz, solo e interferência interespecífica foram espúrias e/ou não significantes. É possível que o padrão aleatório possa ser explicado por características ambientais não consideradas nesse estudo ou por processos estocásticos. A distribuição da espécie pode também ser fortemente afetada pela distribuição de sementes, plântulas e infantes, que inexistiam na área amostrada. Os resultados encontrados sugerem que há variações nas estratégias de ocupação do ambiente e de uso dos recursos ao longo da vida de uma espécie de dossel, no entanto as características ambientais amostradas não foram capazes de explicar como esses caracteres determinam os padrões de recrutamento
Abstract: the present study investigated the ontogenetic and spatial structure of the tree species Savia dictyocarpa (Phyllanthaceae) in the Mata Ribeirão Cachoeira, Campinas municipality, SP. This is a dioecious species that commonly occur on seasonal forest canopy from southeast region of Brazil, and because of its importance we decided to gather information about its life history. To do that, we ask two main questions: 1) Can we define S. dictyocarpa ontogenetic stages using morphometric and architectural variation along the species life? ; 2) Which is the spatial distribution of different ontogenetic stages and which are the environmental factors that influence this distribution? We sampled 0,5 hectares and found 194 individuals distributed in 5 ontogenetic stages: infant, juvenile, immature and adult and senile. We did not found seedlings or reproductive adults in the plots we sampled, but we found some fruits and seedlings on the trail. Thus, seedling stage was described with no consideration of morphometric characteristics. The fruits we found did not have seeds and this fact indicates the absence of flower pollination, which could be caused by low frequency of male individuals or by absence of pollinator. The ramification pattern showed by S. dictyocarpa is correspondent to Massart architectural model, which is common for species that grow under low light conditions. Stages presented significant differences in height and diameter. Juvenile and immature presented smaller diameter increment per unit of height, and adult stage had higher diameter increment per unit of height. This suggests that in early stages a greater investment in height allows then to quickly reach for good light conditions on the forest canopy, disregarding the mechanical stability. We also found that crown length investment per unit of crown width increase along ontogeny, what shows that there is differences between stages to increase the light absorption efficiency. Liana infestation seems to affect adult crown development because individuals with liana have smaller investment in crown length. All stages presented random spatial distribution and juvenile and immature showed the tendency to occupy the same places, probably because they have the same recruitment and growth requirements. All correlations between stages and abiotic and biotic factors (light, soil and interspecific competition) were spurious or nom significant. This random pattern could be explained by environmental characteristics that were not considered here or by stochastic processes. Species distribution could also be strongly affected by seed, seedling or infant distributions, which were not found in the sampled area. These results suggests that there are different environmental occupation and resource use strategies along a canopy species live, however the environmental characteristics sampled here were not able to explain how this strategies determinates recruitment patterns in the space. To understand the absence of seeds and seedlings in the area and to propose conservation and management plans for S. dictyocarpa, reproductive biology and population dynamic studies are required
Mestrado
Ecologia
Mestre em Ecologia
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Villares, Júnior Gilberto Aparecido. "Aspectos morfológicos na ontogenia e relação massa/comprimento de Salminus hilarii Valenciennes, 1850 (Characidae, Salmininae) /." Rio Claro : [s.n.], 2009. http://hdl.handle.net/11449/99521.
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Orientador: Roberto GoiteinBanca: Leandro Muller Gomiero
Banca: Sidnei Eduardo Lima Junior
Resumo: Neste trabalho foram analisados exemplares da espécie Salminus hilarii com a finalidade de verificar as variações morfológicas que possam ocorrer ao longo da vida do peixe, juntamente com a relação massa-comprimento. Para as análises foram tomadas 19 medidas morfométricas, sendo 17 referentes a S. hilarii e duas para as presas ingeridas. Estas medidas foram utilizadas para os cálculos de três índices e 17 valores relativos de atributos morfológicos. As medidas de S. hilarii foram tomadas a partir de exemplares com uma amplitude de tamanho variando entre 50 a 450 mm no comprimento padrão. Foi feita uma comparação entre indivíduos jovens e adultos, machos e fêmeas, e em diferentes classes de comprimento relacionando tais características morfológicas com as velocidades de corrente dos locais onde vivem e o tamanho das presas ingeridas por essa espécie. As amostras para as análises foram coletadas nas bacias dos rios Sorocaba e complementadas com indivíduos depositados no acervo do Departamento de Zoologia provenientes dos rios Jacaré Pepira, Corumbataí (sub-bacia do Tietê), e Mogi Guaçu (sub-bacia do rio Grande). Na comparação entre machos e fêmeas e entre adultos e imaturos foram analisados somente indivíduos capturados no rio Sorocaba onde foi possível a determinação desses grupos. Esse trabalho mostrou que não houve variações significativas entre as sub-bacias dos rios Tietê e Grande. O mesmo foi observado entre machos e fêmeas, mostrando que não há dimorfismo sexual nas características observadas. Entre os imaturos e adultos, assim como nas diferentes classes de comprimento, nove características morfológicas não mostraram diferenças significativas. Nas demais (onze) apresentaram diferenças significativas entre pelo menos duas classes de comprimento. Complementando, foram observadas correlações significativas entre as velocidades calculadas... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: Salminus hilarii specimens were studied using several body measurements and relationships related to their proportions, considering mainly possible ontogenetic changes. Relationships between mass and length were analyzed as well. The usual comparisons made for studies related to distinct species was the subject of the study to compare possible changes occurring during the life of individuals of one species. For this purpose 19 morphometric measurements were obtained, but only 17 were related to individuals of the species e 2 for ingested prey. The S. hilarii measurements used individuals whose standard lengths varied from 50 to 450 mm. This study intended to compare young and adult individuals, as well as males and females. Distinct length classes were established and these data were also used to establish possible relationships between individuals who are usually caught in distinct places of the Sorocaba river, and are submitted to distinct water current effects. Larger individuals use to live in the middle of the river where water flows more rapidly, while the younger ones live near to the river margin or calm waters. Food intake may also suggest some distinct morphological aspects. So, the main organism, when almost intact were also measured. Samples for the analyses were collected at the Sorocaba basin, but were complemented with specimens collectecat the rivers Jacaré-Pepira, Corumbataí (Tietê sub-basin) and Mogi-Guaçu (Rio Grande sub-basin). These specimens are deposited at the Zoology Department (Unesp - Rio Claro). To compare males and females, only fish from the Sorocaba river were considered for analysis. The study permitted to find out that no significant differences exist for fish originated from the Tietê and Rio Grande sub-basins. The same happens for male and female individuals. When immature and adult individuals were compared nine morphological characters... (Complete abstract click electronic access below)
Mestre
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La-aw, Ampornpan Armstrong Joseph E. "Ontogeny of zygomorphic flowers in the Solanaceae." Normal, Ill. Illinois State University, 1992. http://wwwlib.umi.com/cr/ilstu/fullcit?p9311282.
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Thesis (Ph. D.)--Illinois State University, 1992.Title from title page screen, viewed January 31, 2006. Dissertation Committee: Joseph E. Armstrong (chair), Mathew M. Nadakavukaren, Tsan Iuan Chuang, Roger C. Anderson, Jerome R. Cain. Includes bibliographical references (leaves 94-101) and abstract. Also available in print.
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Fröbisch, Nadia. "Ontogeny and phylogeny of small dissorophoid amphibians." Thesis, McGill University, 2008. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=22015.
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This study considers the ontogeny and phylogeny of branchiosaurids and amphibamids, small dissorophoid amphibians from the Upper Carboniferous and Lower Permian. Both clades play a central role in the discussion of the controversial relationships and origins of the three modern amphibian groups from among possible Paleozoic antecedents. An extraordinary fossil record comprising hundreds of specimens and many ontogenetic stages distinguishes branchiosaurids. This allowed for a detailed study of the ossification sequence of the limb skeleton in the branchiosaurid Apateon, which revealed that branchiosaurids share the unique preaxial dominance in limb development with modern salamanders. A detailed revision of the literature on ossification patterns in the limbs of extant and fossil tetrapods formed the basis for this investigation by showing that ossification sequence in the limbs of tetrapods indeed traces general patterns of early skeletogenesis. Furthermore, the excellent preservation of ontogenetic stages in branchiosaurids facilitated the identification of two distinct life history pathways in branchiosaurids, neoteny and metamorphosis. The vast majority of branchiosaurid taxa is neotenic, but members of the species Apateon gracilis were recognized that clearly metamorphosed into terrestrial adults. Events associated with metamorphosis took place in a very short period of time, which represents the first evidence of a condensed metamorphosis outside the modern amphibian groups. Contrary to branchiosaurids, amphibamids represent terrestrial animals with well-ossified limbs and braincase elements. A new genus and species of amphibamid from the Fort Sill fissure fills is described. An updated phylogenetic analysis of amphibamids including all known amphibamid taxa reveals two distinct clades within Amphibamidae, one comprising more plesiomorphic taxa and a second clade with derived members of the clade. Finally, a comprehensive analysis of dissorophoid relationshCette étude envisage l'ontogénie et la phylogénie des branchiosaurides et amphibamides, des petits amphibiens dissorophoïdes du Carbonifère supérieur et du Permien inférieur. Les deux clades jouent un rôle central dans le débat qui considère les liens et les origines des trois groups d'amphibien modern parmi les possibles antécédents du Paléozoïque. Les branchiosaurides possèdent un record exceptionnel de fossiles comportant des centaines de spécimens et plusieurs étapes ontogéniques. Ceci a permis une étude détaillée à propos de la séquence d'ossification des membres du branchiosauride, Apateon. Ce dernier montre que les branchiosaurides partagent avec les salamandres modernes la caractéristique unique d'une dominance préaxiale dans le développement des membres. Une révision détaillée de la littérature concernant les différentes formes d'ossification des membres chez les tétrapodes, modernes et fossilisés, forme la base pour cette investigation. Ceci est réalisé en montrant que la séquence d'ossification parmi les tétrapodes marque le patron général de la squelettogenèse dans les premières étapes du développement. En outre, la préservation spectaculaire des étapes ontogénétiques parmi les branchiosaurides simplifie l'identification de deux cycles biologique, la néoténie et la métamorphose. La plupart des branchiosaurides sont néoténique, pourtant quelques membres de l'espèce, Apateon gracilis, ont été reconnus comme étant complètement métarmorphosés en adultes terrestres. Cette métamorphose a eu lieu durant une courte période de temps, et elle représente la première évidence d'une métamorphose condensée, hors des groups d'amphibien modern. Contrairement aux branchiosaurides, les amphibamides comportent des tétrapodes terrestres qui possèdent une bonne ossification des membres et de la boîte crânienne. Un nouveau genre et nouvelle espèce d'un amphibamide de la fissure de Fort Sill sont ici dé
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Li, Ding-You. "Ontogeny and regulation of cerebral prostaglandin receptors." Thesis, McGill University, 1995. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=39944.
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The objective of this thesis was to test the hypothesis that the decreased effects of PGE$ sb2$ and PGF$ sb{2 alpha}$ on cerebral metabolism and vasculature in the newborn might result from a deficiency of brain EP and FP receptors, which may be downregulated by the relatively high brain levels of PGE$ sb2$ and PGF$ sb{2 alpha}.$This study revealed that the densities of EP and FP receptors and receptor-coupled second messengers in brain synaptosomes and microvessels were much lower in the newborn than in the adult pigs, also the relative distribution of EP receptor subtypes in brain synaptosomes and microvessels differed. For example, in brain synaptosomes, only EP$ sb3$ subtype was present in the newborn, and both EP$ sb2$ and EP$ sb3$ subtypes existed in the adult; EP$ sb1$ subtype was not found in the brain synaptosomes. In contrast, in brain microvessels, more than 80% of EP receptors were of EP$ sb1$ subtype with small amount of EP$ sb3$ subtype. No EP$ sb2$ subtype was detected in the brain microvessels.
In order to determine whether high levels of prostaglandin in the newborn downregulate EP and FP receptors, newborn pigs were treated with cyclooxygenase inhibitors, ibuprofen or indomethacin. The inhibition of prostaglandin synthesis in the newborn pigs significantly increased EP and FP receptor densities as well as receptor-coupled IP$ sb3$ and cAMP production in brain synaptosomes and microvessels of the newborn to levels found in the adult; this effect could be prevented by co-treatment of membranes with stable PG analogs. Vasoconstrictor effects of PGE$ sb2$ and PGF$ sb{2 alpha}$ on cerebral microvessels of the newborn were also increased.
These findings suggest that the relatively low EP and FP receptor densities in the newborn brain are caused by the high levels of prostaglandins and that these receptors and their functions can be upregulated by reducing prostagladin levels.
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Smith, Caitlin Caryl Danielle. "Giraffa camelopardalis: limb bone histology through ontogeny." Master's thesis, Faculty of Science, 2020. http://hdl.handle.net/11427/32351.
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Although there are many studies on mammalian bone histology, there are only a few that have examined the bone histology of artiodactyls, or focused specifically on osteohistological changes during ontogeny. The current study investigates the microanatomy and histology of giraffe limb bones through ontogeny. Mid-diaphyseal sections of humeri, radii, metacarpals, femora, and tibiae of 14 individuals representing individuals of known sex, as well as at different ontogenetic stages (foetal, juveniles, subadults, and adults). Thin sections were prepared for all the bones, and microanatomical (using Bone Profiler) and histological analyses were conducted on each of the sections. The study examined three main aspects, 1) Crosssectional shape changes in limb bones through ontogeny, 2) Histological changes through ontogeny in each of the limb bones, and 3) Histovariability among skeletons. The results of the study show that the foetus and juvenile individuals have round cross-sections, with small vacant medullary cavities, while cross sections of older individuals tend to be oval with variable amounts of cancellous bone surrounding the medullary cavity. The highest bone compactness values were obtained for the humerus and femur of the foetus, whereas the radius, metacarpal, and tibia bone compactness values are similar across the age classes. In terms of histology, this study found that the earlier ontogenetic stages had highly vascularised fibrolamellar bone in their cortices, which contrasts with that of the subadults and adults where more slowly deposited bone tissue occurs. These observations indicate that after rapid initial growth during early ontogeny, osteogenesis (and overall growth) slows down. This research also documents the fusion of the metacarpal III and IV, and the associated changes that occur in the histology. The study also highlights that the tibia is the only bone that has long radial vascular canals in the cortex. Overall the results of this study have provided a much better understanding of the bone histology of giraffes during ontogeny and has therefore filled an important gap in our knowledge of mammalian bone tissues. Furthermore, this study has direct implications for any future palaeohistological studies of fossil giraffids from Langebaanweg in South Africa.
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Abdul, Ghaffar Muhammad Akbar Bin. "Rubber Particle Ontogeny in Taraxacum kok-saghyz." The Ohio State University, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=osu1512031318000982.
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Sharkey, Camilla Rose. "Ontogeny of vision in the Emperor dragonfly." Thesis, University of Bristol, 2015. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.685976.
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Insect visual systems are notable for their ability to operate in an impressive range of photic environments. Whilst insect eyes exhibit a high degree of evolutionary conservatism they exhibit diversity in structure, wavelength sensitivity and polarization sensitivity. Evolutionary adaptations for different visual conditions have been well studied and many different optical, physiological and neural specialisations have been discovered within the visual organs of this invertebrate class. In spite of this, little is known about the adaptive features of aquatic hemimetabolous insect visual systems whose larval and adult developmental stages occupy freshwater and terrestrial environments, respectively. The larval stages of these insects experience different visual conditions from the terrestrial adults. For example, the light in the freshwater environment is spectrally attenuated, causing a shift towards longer wavelengths, intensity levels are lower overall and the polarization of light differs. Thus, with the aim to investigate potential visual adaptations to the aquatic and terrestrial environment, the visual system of the Emperor dragonfly Anax imperator was explored using a range of methods. Firstly, behavioural studies were carried out to test the polarization sensitivity of larval A. imp era tor. Evidence suggests that the larval eye is sensitive to the polarization of light and possibly adapted to reduce the contrast degrading effects of polarized scatter underwater. Secondly, the potential morphological basis underlying this visual capability was investigated, using transmission electron microscopy, and found to differ from that of the adults. Whilst the mechanism for polarization analysis in adult A. imperator is in agreement with other adult dragonflies, namely an orthogonal array of R1 cell microvilli, such a structural arrangement was not found in the larval eye. Despite examining the structure of the larval eye in some detail the mechanism behind their polarization sensitivity is not clear. Finally, the opsins expressed in adult and larval stages were investigated using transcriptomics. A unique set of opsins is expressed at each developmental stage, adult and larval. There were many amino substitutions between opsins expressed at each life stage suggesting that they may exhibit functional differences possibly shifting the peak sensitivity of the visual pigment. Spectral tuning sites were identified suggestive of such shifts. There is also compelling evidence to suggest that the larval stage lacks a UV-sensitive visual pigment. This may be an adaptive feature of the visual system in a freshwater environment where short wavelengths are strongly scattered and attenuated. This study has begun to shed light on the changes that occur in the visual systems of A. imp era tor from the transition from a freshwater to aquatic environment. Results suggest that both the polarization and wavelength sensitivities of these stages may be unique and possibly adapted to their visual environments.
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Ngo, Chi Thao. "ONTOGENY OF EPISODIC MEMORY: A COMPONENTIAL APPROACH." Diss., Temple University Libraries, 2019. http://cdm16002.contentdm.oclc.org/cdm/ref/collection/p245801coll10/id/571412.
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PsychologyPh.D.
Episodic memory binds together the people, objects, and locations that make up the specific events of our lives, and allows the recall of our past in the service of current and future goals. Recent models of memory have posited that the hippocampus instantiates computations critical for episodic memory including mnemonic discrimination, relational binding, and holistic retrieval. Collectively, this set of studies aim to chart the ontogeny of each key components of episodic memory. We found robust improvements in children’s abilities to form complex relational structures and to make fine-grained discrimination for individual items from age 4 to age 6. However, relational memory dependent on context discrimination appears to follow a more protracted development. Furthermore, relational binding and mnemonic discrimination (item and context levels) undergo age-related decrements in senescence. Despite relatively poor relational binding capabilities, children as young as age 4 are able to retrieve multi-element events holistically, such as successfully retrieving of one aspect of an event predicts the retrieval success of other aspects from the same event. Critically, the degree of holistic episodic retrieval increases from age 4 to young adulthood. This multi-process approach provides important theoretical insights into lifespan profile of episodic memory.
Temple University--Theses
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Yeh, Jennifer Jean. "Ontogeny and evolutionary morphology of the skeleton in frogs." Access restricted to users with UT Austin EID, 2001. http://wwwlib.umi.com/cr/utexas/fullcit?p3037029.
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Rosseto, Vanessa. "Aspectos da historia de vida de quatro especies de Trichilia (Meliaceae) na reserva de Santa Genebra, Campinas (SP)." [s.n.], 2007. http://repositorio.unicamp.br/jspui/handle/REPOSIP/316360.
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Orientador: Flavio Antonio Maes dos SantosDissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia
Made available in DSpace on 2018-08-08T20:06:21Z (GMT). No. of bitstreams: 1 Rosseto_Vanessa_M.pdf: 1782142 bytes, checksum: 9d91cab6c070b924e2ff3078c70d69f9 (MD5) Previous issue date: 2007
Resumo: A coexistência de espécies arbóreas em florestas tropicais pode estar associada com a partição dos recursos, através da utilização diferencial dos recursos ambientais ao longo do tempo e espaço. O objetivo do trabalho foi avaliar quais os possíveis mecanismos relacionados com a coexistência de espécies arbóreas simpátricas, Trichilia sp. (Meliaceae), em três fisionomias florestais em um fragmento urbano de Campinas, SP. Para tanto, foram feitos três questionamentos centrais: (1) Qual a heterogeneidade ambiental de três fisionomias florestais (Floresta Estacional Semidecídua, Floresta Paludosa e Floresta de Maria-Preta)? (2) As espécies de Trichilia apresentam características estruturais divergentes ao longo da ontogenia, que possibilitem a coexistência das espécies? (3) O padrão espacial das espécies de Trichilia varia nas diferentes fisionomias e possíveis diferenças estão associadas com fatores ambientais específicos? Para o estudo foram utilizadas três escalas espaciais: escala fisionômica (comparação dos descritores ambientais entre as fisionomias), escala local (comparação entre áreas dentro de uma mesma fisionomia) e escala microlocal (comparação entre parcelas de uma mesma área). A umidade do solo foi o único fator ambiental divergente entre a Floresta de Maria-Preta (MP) e a Floresta Estacional Semidecídua (FES), enquanto que a Floresta Paludosa (FP) não diferiu. MP foi considerada uma floresta monodominante, porque a espécie arbórea maria-preta, Diatenopteryx sorbifolia (Sapindaceae), representou mais de 50% do número de indivíduos e área basal na comunidade arbórea. Supõe-se que a monodominância esteja associada com características do solo. Na escala local e microlocal observou-se grande heterogeneidade ambiental e, em muitos casos, áreas de diferentes fisionomias foram mais semelhantes entre si, do que áreas em uma mesma fisionomia. Ao longo da ontogenia as espécies divergiram entre si na morfologia (presença de caule descamado em T. claussenii e crescimento clonal em T. elegans) e no tamanho. O padrão espacial das espécies de Trichilia não variou nas diferentes fisionomias, exceto em uma área com maior valor de umidade do solo na FP, com a ocorrência apenas de T. pallida. O padrão espacial de Trichilia não foi associado com a heterogeneidade ambiental, com exceção do alagamento, que aparentemente é um fator restritivo para a maioria das espécies arbóreas. Com isso, sugere-se que a coexistência das espécies de Trichilia analisadas esteja mais relacionada com diferenças na ocupação do estrato vertical que cada espécie ocupa do que com diferenças nas preferências ambientais. Além disso, supõe-se que a elevada heterogeneidade ambiental encontrada em todas as fisionomias, possibilite às espécies explorar uma ampla gama de condições ambientais, que podem estar relacionadas com a não preferência de algumas espécies por um habitat específico
Abstract: Tree species coexistence in tropical forests can be associated with resource partitioning through differential utilization of environmental resources along the time and space. The study evaluated coexistence mechanisms associated with sympatric tree species of Trichilia sp. (Meliaceae), in three physiognomies in an urban fragment in Campinas, SP. We approach three questions: (1) Which is the existing environmental heterogeneity in three different physiognomies of the forest fragment (Semideciduous Forest, Swamp Forest and Maria-Preta Forest)? (2) Have Trichilia species structural characteristics divergent along of the ontogeny that makes possible the species coexistence? (3) Are the spatial patterns of Trichilia species variable in the physiognomies analyzed and are possible differences related to specific environmental factors? We evaluated these questions in three spatial scales: a physiognomy scale (variations of environmental factors among physiognomies), a local scale (variations among places in the same physiognomy) and microlocal scale (variations among plots in the same place). The soil moisture was the only one environmental variable that differed between Maria-Preta Forest (MP) and Semideciduous Forest (FES), while Swamp Forest (FP) not differed. MP was considered a monodominant forest, because a tree species ¿maria-preta¿, Diatenopteryx sorbifolia (Sapindaceae), presenting more than 50% of individual numbers and basal area in the tree community. We presumed that monodominance is associated with soil characteristics. High environmental heterogeneity was observed in local and microlocal scale. In many cases, places of different physiognomies were more similar than places in a same physiognomy. Trichilia species diverged through ontogeny in morphology (presence of scaled off stem in T. claussenii and clonal growth in T. elegans) and in size. Spatial pattern of Trichilia species not varied in the different physiognomies, except for one sample with greater soil moisture in the FP, where only T. pallida occurred. Spatial pattern of Trichilia was not associated with environmental heterogeneity, except for the flooding, that seeming was restrictive to the establishment of the majority of the species. Then we supposed that Trichilia species coexistence is more associated with differences in the vertical strata that each species occupies than with differences in environmental preferences. Furthermore, we suggests that the high environmental heterogeneity encountered found in all physiognomies, makes possible to the species explore an ample gamma of ambient, that can be related with no preference of species for specific habitats
Mestrado
Mestre em Ecologia
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Hughes, Carys Farrell. "Object play in the domestic horse." Thesis, University of Southampton, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.247039.
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Fowler, Shannon Leone. "Ontogeny of diving in the Australian sea lion /." Diss., Digital Dissertations Database. Restricted to UC campuses, 2005. http://uclibs.org/PID/11984.
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Reikie, Brian Andrew. "Early life immune ontogeny in a vulnerable population." Thesis, University of British Columbia, 2016. http://hdl.handle.net/2429/58210.
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The first year of life represents a time of marked susceptibility to infections, particularly in resource-poor regions and regions where HIV is endemic, such as sub-Saharan Africa. Infants that are exposed to HIV are among the World’s most vulnerable to infectious morbidity and mortality. Immune defense mechanisms may differ between global regions with high rates of childhood death and disease. This dissertation examines innate immune development throughout the first year of life in HIV unexposed (UE) South African infants, and compares their immune development with HIV-exposed uninfected (HEU) South African infants. Clinical outcomes and adaptive immune responses to vaccination were also compared between HEU and UE infants. Specifically, infection incidence and severity were correlated with multidimensional assessments of immune profiles, including innate immune responses to pathogen-associated stimuli, as well as antibody responses to vaccination, all contrasting HEU and UE infants. I found that monocyte, classical dendritic cell and plasmacytoid dendritic cell responses in our cohort were mostly similar to responses measured in other global regions. However, responses to endotoxin matured more rapidly in South African infants. HEU mononuclear cells demonstrated enhanced pro-inflammatory responses when compared to UE, particularly during the first 6 weeks of life, and altered responses were specific to pathogen type. HEU vaccine responses were similar, but in some instances developed protective titers more rapidly than UE. Incidence of infection was equivalent between HEU and UE. However, HEU infants experienced more severe infections, and peak relative risk occurred within the first 12 months of life. This cohort study represents the first prospective, longitudinal description of immune ontogeny throughout the first year of life. My PhD dissertation provides a thorough examination of innate immune development during this time period. HEU are a population that suffers disproportionately from infectious disease, and our findings suggest HEU infants have altered immune defense mechanisms. This collection of work provides a foundation to mechanistically dissect etiological factors that predispose high-risk groups, such as HEU infants, to suffer increased infectious morbidity and mortality.Medicine, Faculty of
Experimental Medicine, Division of
Medicine, Department of
Graduate
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Goodale, Lindsay. "Kinematics of the chameleon feeding mechanism through ontogeny /." Connect to online version, 2008. http://ada.mtholyoke.edu/setr/websrc/pdfs/www/2008/263.pdf.
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Pretheeban, Manoja. "Ontogeny of hepatic drug metabolizing enzymes in sheep." Thesis, University of British Columbia, 2010. http://hdl.handle.net/2429/29395.
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Administration of therapeutic, supplemental and social drugs to the mother during pregnancy exposes the fetus to these medicines and their metabolites, which can cause defects in nervous, renal, cardiac and metabolic functions. Hepatic metabolic enzymes such as cytochrome P450 (CYP) 2A6, 2C19, 2D6 and UDP glucuronosyltransferases (UGT) 1A6, 1A9, 2B7 are important for the metabolism of many drugs. In order to understand whether these drugs are safe enough during pregnancy and in postnatal period, knowledge of the expression levels of these enzymes in different developmental stages is important.
Therefore we proposed to clone the CYP and UGT genes and quantify these enzymes at gene and protein levels at different developmental stages such as fetus, newborn and adults. This study was performed in sheep (adult n=4; newborn n=3; and fetus n=3) liver to compare the mRNA and protein expression levels of the above enzymes and a regulatory factor, Hepatic Nuclear Factor 4α (HNF4α). The effect of antenatal glucocorticoid on these enzymes was also studied by infusion of cortisol (0.45mg/h; 80h) to another group of fetuses (n=5). Sheep sequences were cloned and real time PCR was performed to analyze the relative mRNA expression levels in the above four groups. Microsomes were prepared and western blot analysis was performed using human or rat antibodies to measure the relative protein expression levels.
In terms of mRNA and protein expression of the above mentioned enzymes, fetal and newborn levels were very low compared to the adult. Some CYP proteins (CYP2A, CYP2C) were absent in the fetus and even in newborns (CYP2A). Sheep UGT protein levels were not measured since the human UGT antibodies did not work. Glucocorticoid plays a role in up regulating both the mRNA and protein expression of CYP2D6. Moreover the correlation observed between the above enzymes and HNF4α indicates a possible regulatory role in sheep similar to that in humans.
The findings of this study follow a similar pattern found in the human and indicate that fetal and newborn lambs have a reduced ability to metabolize drugs that are substrates of these CYP isoforms.
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Gimenes, Marcelo. "An approach to machine development of musical ontogeny." Thesis, University of Plymouth, 2008. http://hdl.handle.net/10026.1/1812.
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This Thesis pursues three main objectives: (i) to use computational modelling to explore how music is perceived, cognitively processed and created by human beings; (ii) to explore interactive musical systems as a method to model and achieve the transmission of musical influence in artificial worlds and between humans and machines; and (iii) to experiment with artificial and alternative developmental musical routes in order to observe the evolution of musical styles. In order to achieve these objectives, this Thesis introduces a new paradigm for the design of computer interactive musical systems called the Ontomemetical Model of Music Evolution (OMME), which includes the fields of musical ontogenesis and memetlcs. OMME-based systems are designed to artificially explore the evolution of music centred on human perceptive and cognitive faculties. The potential of the OMME is illustrated with two interactive musical systems, the Rhythmic Meme Generator (RGeme) and the Interactive Musical Environments (iMe). which have been tested in a series of laboratory experiments and live performances. The introduction to the OMME is preceded by an extensive and critical overview of the state of the art computer models that explore musical creativity and interactivity, in addition to a systematic exposition of the major issues involved in the design and implementation of these systems. This Thesis also proposes innovative solutions for (i) the representation of musical streams based on perceptive features, (ii) music segmentation, (iii) a memory-based music model, (iv) the measure of distance between musical styles, and (v) an impi*ovisation-based creative model.
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Hyatt, Melanie Ann. "Ontogeny and nutritional programming of ovine liver growth." Thesis, University of Nottingham, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.438323.
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Battersby, Anna. "The ontogeny of innate immunity in Gambian infants." Thesis, Imperial College London, 2017. http://hdl.handle.net/10044/1/61398.
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Background: Neonatal infections are a major cause of childhood morbidity and mortality world-wide. Our limited understanding of how the neonatal immune system functions is one of the major roadblocks to the prevention and treatment of these infections. Pattern recognition receptors (PRRs) detect common microbial antigens and are critical in the early innate immune response. Mucosal exposure to bacterial antigen may shape the ontogeny of infant immunity. Methods: Longitudinal cohort study of healthy Gambian infants assessed at 6 time-points over the first year of life. Microbiological culture techniques were performed to detect bacteria colonising the nasopharynx. Secreted cytokine and antimicrobial protein (AMP) levels were measured in supernatants from in vitro whole blood assays testing responses to PRR agonists. Quantitative real-time polymerase chain reaction was used to measure PRR agonist induced transcriptional responses in whole blood. Results: 54 eligible infants were recruited at birth and 46 were followed-up until 12- months old. Bacterial colonisation of the nasopharyngeal mucosa occurred early in life. Infant age and bacterial colonisation status were significantly associated with the magnitude of specific PRR agonist induced intracellular immune pathway gene transcription and extracellular innate immune protein secretion. Co-stimulation of infant blood with NLR and TLR agonists induced synergistic effects on innate immune responses. Conclusions: Innate immune responses in Gambian infants are age-dependent and are associated with specific nasopharyngeal bacterial colonisation particularly during the neonatal period.
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Schweitzer, Peter Neil. "Inference of ecology from the ontogeny of microfossils." Thesis, Massachusetts Institute of Technology, 1989. http://hdl.handle.net/1721.1/57929.
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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Earth, Atmospheric, and Planetary Sciences, 1989.Includes bibliographical references (leaf 148).
by Peter Neil Schweitzer.
Ph.D.
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Meiklejohn, Stuart J. "The role of BMP signalling in HSC ontogeny." Thesis, University of Oxford, 2013. http://ora.ox.ac.uk/objects/uuid:305597a8-b8cb-42ff-88fd-34b3dd5bf39b.
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The haematopoietic stem cell (HSC) is found in the adult human bone marrow, where it gives rise to all the circulating blood cells throughout adulthood. Understanding the signalling events that programme these cells during development will improve HSC in vitro culture, their generation from embryonic stem cells or induced pluripotent stem cells, and their potential therapeutic application. HSCs bud from the floor of the dorsal aorta and seed the bone marrow via circulation. The precursors to the dorsal aorta and HSCs are called haemangioblasts, which are found in the dorsal lateral plate mesoderm in Xenopus. The knowledge of the location of these precursors allows their programming to be studied in detail during embryonic development. A key pathway implicated in the programming of HSCs is the BMP signalling pathway. Here, using both a small molecule inhibitor and a transgenic Xenopus line, BMP signalling has been inhibited post-gastrulation without perturbing the gross morphology of the embryo. This has shown that BMP signalling is required for HSC programming in the dorsal lateral plate mesoderm via the expression of a critical haematopoietic transcription factor, gata2. Morpholino knockdown of evi3has revealed it to be essential for HSC programming in the dorsal lateral plate mesoderm, where it is required for the expression of gata2. Furthermore, as evi3 is known to bind to the active BMP signalling complex, and as evi3 knockdown phenocopies post-gastrulation BMP inhibition, evi3 appears to be required for BMP signalling to initiate gata2 expression in the DLP. Taken together, the findings presented here demonstrate an essential post-gastrulation role of BMP signalling and Evi3 for programming HSCs in Xenopus.
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Cole, Sara Mae. "Ergodic ontogeny| Influences of interactive media on identity." Thesis, University of Maryland, Baltimore County, 2014. http://pqdtopen.proquest.com/#viewpdf?dispub=3609856.
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Video games represent the future of storytelling, changing the impact of cultural narratives in important ways through a process of learning and internalization of game content that alters players’ perceptions of self and reality. Continued rigorous research of interactive media is necessary because of the speed at which technology changes its capabilities and the dominant nature of its format—it is how many people will tell, hear, and experience stories, culture, and values in the coming years. This dissertation argues that a deeper understanding of how people play video games and what these play experiences mean must rely on interdisciplinary lenses of analysis that value player reports, programming choices, and cultural narratives equally. I establish a theoretical and methodological approach that defines elements of what it means to play video games, and study the qualitative influence of game-play on thought and behavior through pragmatic analysis of interview data. Samples of masculine discourses of game play in the United States provide a starting point for this exploration of video game impact through discussions of play theory, narratology, game programming and interaction with interactive media hardware.
Common social concerns regarding increased violence, aggression, or de-socialization as a result of this medium were not represented in the population presented in this dissertation. Players recognized the allure of the so-called negative aspects of video games, but ultimately expressed a decided disconnect between the real world and virtual experiences of play, describing cathartic and therapeutic reasons for their enjoyment of those elements. An interdisciplinary approach to video game research must be embraced, despite a constant call for quick, universal answers to their most common critiques. Foundational themes for understanding the influence of interactive digital play experiences on personal identity and ideology construction are demonstrated through thematic and sociolinguistic analyses of in-depth interview data. These include play theory, narratology, human-computer interaction theory, and player report data. I draw on the established theoretical backgrounds of these disciplines to suggest a new term, ergodic ontogeny, to describe this complex process of personal development resulting from influences of interactive digital media gaming that reach beyond play experiences.
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Turley, Kevin. "Ankle Morphology: Interface of Genetics, Ontogeny and Use." Thesis, University of Oregon, 2013. http://hdl.handle.net/1794/13266.
Full textAbstract:
A central concept in Evolutionary theory is the character trait. It provides a context in which to explore differences and similarities among taxa, both extant and extinct. It is expanded in scope in Evolutionary Developmental theory to functional units with a biological role, "evolutionarily stable configurations." The talo-crural joint is such a configuration, a highly canalized structural unit in primates forming the interface between organism, and foot and substrate. It is a microcosm in which to examine the relationship of shape with environment and function and the interplay of genetics, ontogeny, and use.
Geometric Morphometric analysis of landmark data was employed in studying the articular surfaces of the talus in a diverse sample of adult specimens in nine catarrhine taxa. The influence of four factors on talar shape was examined: superfamily, a proxy for phylogeny; size and mass, a proxy for physical attributes; and substrate preference, a proxy for behavior. All significantly affected shape, and substrate preference was unrelated to the others. Appositional articular morphology, the shape of the subchondral bone surfaces of the talo-crural joints in an expanded sample of 12 taxa, showed a significant effect of the four proxies on the tibial and talar components, and substrate preference was weakly related to the other proxies in each. Singular Warp analysis of the cross-covariance matrices of the joints demonstrated sorting of taxa by substrate use and signals of convergent and divergent evolution among hominoids and cercopithecoids in joint shape. The ontogeny of the appositional articular shape was examined using adult and subadult specimens grouped by molar eruption. Singular Warp analysis demonstrated a genetic signal in the subadults, strongest in the slowly maturing African hominoids, and an epigenetic signal across taxa to substrate use in the adults.
The talo-crural joint, a highly canalized, modular, and integrated "evolutionarily stable configuration," provides a model for the study of the evolution of shape. The epigenetic signal observed is consistent with plasticity or developmental plasticity in response to the interaction of the joint complex with the environment due to a behavioral effect, substrate use.
This dissertation included previously unpublished, co-authored material.
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Pereira, Junior Eduardo João [UNESP]. "Ontogenia do óvulo e da Antera de Cybistax antisyphilitica (Mart.) Mart. (Bignoniaceae)." Universidade Estadual Paulista (UNESP), 2011. http://hdl.handle.net/11449/92494.
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Caracteres embriológicos possuem valor sistemático e sua utilidade foi demonstrada por diversos autores para elucidar o posicionamento filogenético de certas famílias de angiospermas. Este estudo visa analisar a ontogenia das estruturas reprodutivas de Cybistax antisyphilitica, com o propósito de acrescentar dados embriológicos relevantes ao delineamento filogenético da família, ou de categorias taxonômicas infrafamiliares. As características embriológicas observadas demonstraram similaridade com espécies pertencentes à ―Tabebuia alliance‖ cuja embriologia já foi investigada. Observou-se durante a ontogenia do óvulo de C. antisyphilitica que apenas o ginósporo calazal se desenvolve e, durante sua diferenciação em célula-mãe do saco embrionário, a face micropilar de sua parede celular assume uma conformação côncava, na qual há grande deposição de calose. No estádio octonuclear, há acúmulo de uma substância fibrogranular entre o endotélio e a parede do ginófito fazendo com que o saco embrionário apresente um característico afunilamento mediano. Em relação a ontogenia da antera da espécie estudada, verificou-se que as camadas tapetais são dimórficas, embora ao final do estádio pré-meiótico se tornem similares; embora, após a meiose, o dimorfismo se acentua novamente nas camadas tapetais. Os amiloplastos das células-mãe dos andrósporos são herdados pelos andrósporos e grãos de pólen deles resultantes. Os amiloplastos dos grãos de pólen gradualmente aumentam em número e tamanho em um único ciclo de amilogênese/amilólise. Com base nos dados obtidos conclui-se que a configuração da parede distal do ginósporo calazal e o acúmulo de secreção na porção mediana do saco embrionário são características não relatadas para outras espécies da família e podem...
Embryological characters have systematic value and its usefulness has been demonstrated by several authors to elucidate the phylogenetic position of certain angiosperms families. This study aims to analyze the ontogeny of reproductive structures of Cybistax antisyphilitica, with the purpose of adding relevant embryological data to the phylogenetic design of the family or, infra-familiar taxonomic categories. The embryological features observed was similar to species belonging to ―Tabebuia alliance‖ whose embryology has been investigated. During the ontogey of C. antisyphilitica ovule, only the chalazal megaspore develops, and in the course of its differentiation in the embryo sac mother cell, the micropylar side of its cell wall assumes a concave conformation in which there is an expressive deposition of callose. In the octonuclear stage, there is an accumulation of a fibrogranular substance between the endothelium and megagametophyte wall causing a bottleneck in the middle portion of embryo sac. For anther ontogeny of the species studied, the tapetal layers are dimorphic, although becoming similar at the late pre-meiotic stage. After meiosis, the dimorphism is accentuated between the two tapetal layers. The microspore mother cell amyloplasts are inherited by the microspores and the resulting pollen grains. The pollen grain amyloplasts gradually increasing in number and size in a single amylogenesis/amylolyse cycle. Based on the obtained data we concluded that the configuration of the distal wall of the chalazal megaspore and the accumulation of secretion in the median portion of embryo sac are characters not reported for other species of the family, and may possibly be autapomorphic characters. Regarding the ontogeny of the anther, Cybistax antisyphilitic showed a multistratified fibrous endothecium... (Complete abstract click electronic access below)
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Brum, Heloisa Dantas. "Distribuição espacial de três espécies de palmeiras do gênero Oenocarpus ao longo de um gradiente edafo-topográfico na Amazônia Central." [s.n.], 2011. http://repositorio.unicamp.br/jspui/handle/REPOSIP/316362.
Full textAbstract:
Orientadores: Flavio Antonio Maës dos Santos, José Luís Campana CamargoDissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia
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Resumo: As espécies do gênero Oenocarpus que ocorrem na Amazônia Central são O. bacaba, O. bataua e O. minor e apresentam distribuição espacial diferente ao longo do gradiente topográfico da região, caracterizado pelos habitats de baixio, vertente e platô. As plântulas das três espécies são encontradas em todos os habitats. Entretanto, os adultos de O. bataua só ocorrem nos habitats de baixio, e os de O. bacaba e O. minor só são encontrados nas vertentes e platôs. O objetivo geral deste estudo foi descrever a distribuição espacial dos estádios ontogenéticos dos indivíduos de três espécies do gênero Oenocarpus e entender como estes indivíduos são afetados pelos fatores abióticos que caracterizam os habitats de baixio, vertente e platô na Amazônia Central. Em campo foram instaladas 72 parcelas de 5x50 m nos baixios, vertentes e platôs em três reservas de floresta contínua pertencentes à Área de Relevante Interesse Ecológico do Projeto Dinâmica Biológica de Fragmentos Florestas (PDBFF), a cerca de 80 Km de Manaus, AM. Os habitat se diferenciam pelas características edáficas, principalmente textura e teor de água do solo. A abertura de dossel variou pouco entre os habitats. Foram determinados cinco estádios ontogenéticos para as três espéceis: plântula, infante, juvenil, adulto imaturo e adulto reprodutivo. A distribuição espacial das espécies não foi correlacionada com nenhuma das variáveis edáficas, exceto O. bataua, que apresentou correlação positiva com o teor de água do solo a partir do estádio de juvenil. Este estudo permite afirmar que diferenças no ambiente físico da Amazônia Central podem ser importantes em escala local para a distribuição de palmeiras. Embora somente alguns estádios ontogenéticos das três espécies tenham respondido às características edáficas, a segregação espacial entre os habitats é evidente e a relação entre cada espécie e o ambiente varia com o desenvolvimento ontogenético, como uma forma de segregação de nichos em escala local, visível nos indivíduos adultos destas espécies co-genéricas
Abstract: The species of the genus Oenocarpus occurring in Central Amazon are O. bacaba, O. bataua and O. minor. They present a distinct spatial distribution along the topographic gradient of the region, characterized by lowlands, slopes and plateaus. Seedlings of this species are found in all habitats. However, adults of O. bataua only occur in lowland habitats and, by instane, O. bacaba and O. minor are found only in the slopes and plateaus. The aim of this study was to describe the spatial distribution of individuals' ontogenetic stages of three species of the genus Oenocarpus and to understand how these individuals are affected by environmental factors that typify the habitats of lowland, slope and plateau in the Central Amazon region. A total of 72 plots of 50x5 m were set up at the three habitats of three continuous forest reserves of the Biological Dynamics of Forest Fragments Project (BDFFP), located about 80 km from Manaus, AM. The three habitats can be distinguished by some soil characteristics, especially texture and water content. The canopy cover of the trhee habitats were similar. Five ontogenetic stages were determined for the three species: seedling, infant, juvenile, immature adult and reproductive adult. The patterns of spatial distribution for the three species was not correlated with any of the soil variables, except for juveniles of O. bataua, which showed a positive correlated with water content. This study allows us to assert that differences in the physical environment of Central Amazonia may be important on a local scale for the distribution of palms trees. Although only some ontogenetic stages of three species have responded to the soil characteristics, spatial segregation amongst habitats was evident and the relationship between each species and the environment varies accordantly to the ontogenetic development, as a niche segregation form on a local scale, visible in adults of this co-generic species
Mestrado
Ecologia
Mestre em Ecologia
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Tölke, Elisabeth Emília Augusta Dantas 1984. "Estudos estruturais em órgãos reprodutivos de Tapirira guianensis Aubl. (Anacardiaceae)." [s.n.], 2013. http://repositorio.unicamp.br/jspui/handle/REPOSIP/315563.
Full textAbstract:
Orientadores: Sandra Maria Carmello Guerreiro, Silvia Rodrigues MachadoDissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia
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Resumo: Tapirira guianensis Aubl. (Anacardiaceae) conhecida popularmente como pau-pombo é uma espécie importante para uso madeireiro, medicinal e pode ser empregada na recuperação de áreas degradadas e de matas ciliares. Diversas substâncias são produzidas em estruturas secretoras específicas, sendo a presença de canais e cavidades secretoras característica universal da família. Na literatura é relatada a presença de disco nectarífero intraestaminal nas flores de muitas Anacardiaceae. No entanto, estudos anatômicos e histoquímicos recentes não comprovaram a secreção de néctar por esta estrutura. Além disso, nestes trabalhos foi verificada a persistência do disco intraestaminal no fruto maduro de T. guianensis, bem como a presença de um endocarpo secretor em frutos não maduros. Aliado a estes fatores, a ontogenia de frutos e sementes também é um tema pouco explorado frente ao grande número de espécies da família. A anatomia dos frutos de Anacardiaceae tem-se mostrado de grande valor sistemático. Assim, o presente trabalho consistiu em verificar a estrutura e ultraestrutura do disco glandular de flores e frutos de T. guianensis, bem como examinar a natureza da secreção produzida e estudar a ontogenia do fruto e da semente. Com os resultados alcançados foi possível determinar que a glândula floral das flores hermafroditas de T. guianensis é uma glândula de secreção mista, produzindo néctar com predominância de sacarose, lipídios e substâncias fenólicas. Ultraestruturalmente esta glândula passa por mudanças profundas ao longo do desenvolvimento da flor, inicialmente rica em amiloplastos e posteriormente plastídios desprovidos de amido e mitocôndrias repletas de gotículas de óleo, indicando a mudança da secreção antes predominantemente hidrofílica para lipofílica. No que diz respeito à anatomia do fruto, observou-se que o mesmo possui características típicas da tribo Spondieae, porém algumas delas indicam uma condição menos derivada da espécie, como ausência de opérculo e endocarpo relativamente fino quando comparado com outras espécies da mesma tribo. O pericarpo possui grande quantidade de canais resiníferos na região do mesocarpo, epicarpo produzindo substâncias fenólicas e lipídios, e por meio de microscopia eletrônica de transmissão pôde-se observar o modo de secreção, as organelas envolvidas do processo, bem como a estrutura celular. A semente provém de um óvulo único, anátropo, bitegumentado, crassinucelado de funículo longo. A semente não possui camada mecânica, tem a exotesta e endotégmen ricos em substâncias fenólicas, cristais no mesotégmen, desenvolvimento de paquicalaza parcial, hipóstase fenólica e lipídica, permanência de funículo aderido ao envoltório da semente, formando um arilo vestigial. O embrião armazena grande quantidade de proteínas e amido, indicando uma condição de transição da espécie, pois em Anacardiaceae as reservas são constituídas principalmente por proteínas e lipídios. O fruto e semente apresentaram algumas características anatômicas possivelmente relacionadas à dispersão como, formação de aerênquima no mesocarpo interno e na mesotesta, acúmulo de amido no mesocarpo. O trabalho traz contribuições no estudo de glândulas florais em Anacardiaceae e na área de ontogenia de frutos e sementes
Abstract: Tapirira guianensis Aubl. (Anacardiaceae) well-known as "pau-pombo" is an important species with uses as timber, in medicine and can be employed recovering degraded areas and riparian forests. Several substances are produced in specific secretory structures and the presence of cavities and ducts are universal features in the family. In literature is reported the presence of an intrastaminal receptacular nectary in the flowers of many Anacardiaceae, however anatomical and histochemical recent studies did not support the nectar secretion by this structure. Furthermore, in other studies were found the persistence of intrastaminal receptacular gland in T. guianensis ripe fruits and the presence of a secretory endocarp in unripe fruits. Allied these factors, the ontogeny of fruits and seeds is also a relatively unexplored subject, in contrast with the large number of species from this family. The fruit anatomy of Anacardiaceae has proved great systematic value. Thus, the present study verified T. guianensis structure and ultrastructure of flowers and fruits intrastaminal gland and examined the nature of substances produced as well the fruit and seed development. With the results obtained it was possible provide that the T. guianensis floral gland of hermaphrodite flowers is a mixed secretion gland, producing nectar with sucrose predominance, lipids and fenolic substances. Ultrastructurally, this gland undergoes deep changes during the development of the flower, originally rich in amyloplasts and subsequently chloroplasts devoids of starch and mitochondria replete with oil droplets, indicating the change in the secretion predominantly hydrophilic to lipophilic. With respect to the fruit anatomy, it was observed characteristics typical of the tribe Spodieae, but some of them indicate a condition less derived of this species, such as lack of operculum and endocarp relatively thin compared to other species of the same tribe. Pericarp has a large number of resiniferous ducts in mesocarp region, and epicarp produces phenolic substances and lipids. By transmission electron microscopy it was possible to observe the way of secretion, the organelles involved in process and the cell structure. Seed comes from a single ovule, anatropous, bitegmic, crassinucelate with longe funicle. Seed does not have mechanical layer, has exotest and endotegmen rich in phenolic substances, crystals in mesotegmen, development of partial pachycalaza, phenolic and lipid hypostasis, permanence of the funicle attached to the seed-coat, forming a vestigial aril. The embryo stores large amounts of protein and starch, indicating a transitional condition in the species, because Anacardiaceae reserves comprehend mainly protein and lipids. Fruit and seed showed anatomical characteristics possibly related to dispersion, like formation of aerenchyma in the inner mesocarp and mesotest, starch accumulations in mesocarp. The work brings contributions in the study of Anacardiaceae floral glands and in the area of fruit and seeds ontogeny
Mestrado
Biologia Vegetal
Mestra em Biologia Vegetal
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Sousa, Erika Zolcsak de. "O desenvolvimento embrionário da Piapara - Leporinus elongatus (Pisces, Anostomidae) utilizando marcadores ósseos." Universidade de São Paulo, 2014. http://www.teses.usp.br/teses/disponiveis/10/10132/tde-09102014-154150/.
Full textAbstract:
O conhecimento dos estágios iniciais do desenvolvimento embrionário de peixes é de extrema importância para o estudo de espécies nativas com potencial para a piscicultura, uma vez que permite o estabelecimento de diretrizes para a criação destes animais. Este projeto estudou o desenvolvimento embrionário da piapara (Leporinus elongatus), um peixe de grande importância na pesca esportiva e profissional na bacia dos rios Pardo e Jequitinhonha, visando compreender as fases desse animal em diversos estágios de desenvolvimento, utilizando marcadores ósseos que possibilitaram visualizar o desenvolvimento ósseo da espécie. As Proteínas Ósseas Morfogenéticas (BMP-2 e BMP-4) são consideradas moléculas essenciais reguladoras no desenvolvimento embrionário e na formação óssea, sendo ainda pouco estudadas em peixes; tais proteínas puderam ser observadas apenas no estádio larval até o período juvenil, não sendo evidenciadas nos estágios anteriores. Foram utilizadas também técnicas de Microscopia Eletrônica de Varredura e histológicas, onde foi possível visualizar as fases principais do desenvolvimento embrionário, entre elas, clivagens, diferenciação do embrião, formação dos órgãos principais, abertura de boca, pigmentação dos olhos, surgimento das nadadeiras e sistema branquial, dados estes que facilitam a compreensão sobre a ontogenia; além de criar dados embriológicos e anatômicos dessa espécie ainda pouco explorada, conhecimentos estes, imprescindíveis à biologia pesqueira e cultivo das mesmas, sendo também um auxiliar a novas pesquisas.The knowledge of the early stages of embryonic development in fish is of great importance for the study of native species with potential for aquaculture, since it allows the establishment of guidelines for the breeding of these animals. This project studied the embryonic development of piapara (Leporinus elongatus), a fish of great importance in professional and amateur fishing from the basin of the Pardo and Jequitinhonha rivers, aiming to understand the various stages of development, using bone markers that allowed observation of the bone development in this species. The Bone Morphogenetic Proteins (BMP-2 and BMP-4) are known as key regulatory molecules in embryonic development and bone formation, and information on this subject is scarce in fish. Results shown these proteins could be observed only between the larval to the juvenile stage, not being seen at earlier stages. Scanning electron microscopy and histological techniques, where it was possible to observe the main stages of embryonic development , including , cleavage , embryo differentiation , development of major organs , mouth opening , eye pigmentation , appearance of fins and gills system. This data contributed for the understanding of ontogeny, and provided embryological and anatomical data that may help other studies like reproductive biology of this species that surely will improve reproductive techniques, important goal for raising the piapara.
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Hamachi, Leonardo. "Competência para a expressão da fotossíntese CAM em plantas de Guzmania monostachia (Bromeliaceae) em diferentes fases ontogenéticas." Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/41/41132/tde-28032014-085028/.
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A Guzmania monostachia é uma espécie de bromélia heteroblástica, ou seja, na fase juvenil, ela apresenta a forma atmosférica e na fase adulta, ela adquire uma estrutura chamada de tanque, que pode armazenar água e nutrientes em momentos de seca esporádica. Ela também é reconhecida por ser C3-CAM facultativa, podendo ser induzida ao CAM através de estímulos ambientais como o a escassez d\'água. Estudos com outras espécies competentes para a expressão do CAM, há relatos de que tecidos jovens expressariam preferencialmente a fotossíntese C3 e passariam a expressar o CAM à medida que se tornassem maduros. No Laboratório de Fisiologia do Desenvolvimento Vegetal a indução do CAM em plantas adultas da espécie G. monostachia por déficit hídrico foi estudada e pôde-se constatar que essa bromélia possui folhas com regiões funcionais distintas: a porção basal seria responsável pela absorção de água e nutrientes e a porção apical encarregada de realizar, principalmente, a fotossíntese. Contudo, ainda não se possuía informação sobre como a ontogenia e as mudanças morfológicas estariam influenciando a competência para a expressão do CAM em folhas inteiras e nas diferentes porções foliares de G. monostachia. A fim de se caracterizar o CAM nesta espécie ao longo da ontogenia, foram selecionadas plantas em 3 fases ontogenéticas (Atmosférica, Tanque-1 e Tanque-2) e das fases Tanque-1 e 2 foram separados grupos de folhas representando 3 estágios de desenvolvimento (F1 - as 7 mais internas da roseta, F2- as 7 folhas seguintes da roseta e F3 - as 7 folhas localizadas mais na base da roseta). As plantas foram submetidas a 7 dias de déficit hídrico por meio da suspensão de rega. Outra coleta de material vegetal foi realizada com plantas Tanque-2 separando-se as folhas em grupos representando os mesmos 3 estágios de desenvolvimento utilizados no experimental anterior e dividindo-as em porções basal e apical. Medidas morfométricas foram feitas para caracterizar cada fase ontogenética. O teor de água dos tecidos das folhas foi determinado e o CAM foi detectado através do ensaio enzimático da PEPC, da MDH e da quantificação dos ácidos orgânicos (ácido cítrico e málico). As plantas Tanque-2 apresentaram mais que o dobro da capacidade de estocagem de água comparativamente às plantas Tanque-1. As plantas atmosféricas sofreram as maiores perdas de água em sua folhas (aproximadamente 50%); já as plantas com tanque tiveram decréscimos mais discretos no teor hídrico (em torno de 15%). Plantas de todas as fases ontogenéticas acumularam significativamente ácido málico durante a noite, evidenciando que, independente da ontogenia, as plantas foram competentes para expressar o CAM. De maneira semelhante, tanto as folhas mais jovens quanto as mais maduras exibiram acúmulos significativos de ácido málico, indicando que elas foram capazes de expressar o CAM nos 3 estágios de desenvolvimento escolhidos para este estudo. Portanto, no conjunto dos experimentais realizados, sugere-se que o fator mais importante para a expressão do CAM em plantas de G. monostachia seja o teor de água dos tecidos foliares e não a ontogenia. Plantas atmosféricas apresentaram a maior perda de água (aproximadamente 50%) concomitantemente à expressão do CAM. Já as regiões apicais dos grupos de folhas F1 das plantas Tanque-2 exibiram um decréscimo de 7% com acúmulo noturno de ácido málico e os grupos F2 e F3 perderam 12% da água de seus tecidos, resultando na inibição do CAM. Há indícios que o transporte de água nas plantas com tanque sob estresse hídrico ocorra das folhas mais maduras para as folhas mais jovens. Aparentemente, plantas jovens atmosféricas de G. monostachia possuem a capacidade de manter seu metabolismo mais ativo mesmo em condições que resultem em uma baixa quantidade de água nos tecidos foliares, indicando um certo grau de tolerância à seca. Ao contrário, nas plantas com tanque, essa capacidade parece não ser tão acentuada, sugerindo que esta fase esteja mais relacionada com estratégias de evitação à secaGuzmania monostachia is a species of heteroblastic bromeliad, in other words, whereas in the juvenile phase, it assumes the atmospheric form, in the adult, it acquires a structure called a tank, by which water and nutrients can be stored in moments of sporadic drought. It is also recognized through being C3-CAM facultative, thus inducible to CAM through environmental stimuli, such as the lack of water. In the young plants of other species capable of CAM expression, there are reports of preferential C3 photosynthesis expression in young tissues, leading to CAM expression on reaching maturity. In the Laboratory of Plant Development Physiology, studies were made of CAM induction in adult plants of the species G. monostachia during the lack of water at times of drought. It was noted that this bromeliad possessed leaves with distinct functional regions: whereas the basal portion was responsible for the absorption of both water and nutrients, the apical was mainly responsible for photosynthesis. Nonetheless, there was no available information on how ontogeny and morphological changes could influence competence for CAM expression throughout the whole leaf, as well as in the different parts. In order to characterize CAM in this species throughout ontogeny, selection was concentrated on plants in the three ontogenetic phases (Atmospheric, Tank-1 and Tank-2), as well as in the Tank-1 and Tank-2 phases by separating groups of leaves representing the three stages of development in the rosette, viz., Stage1 - the seven inner-most leaves, Stage2 - the next seven, and Stage3 - the seven located more at the base. By suspending irrigation, all the plants were submitted to 7 days without water, whereupon further material was collected from Tank-2 plants. The leaves thus obtained were first divided into groups representing the same three developmental phases as used in the preceding experiment, and then separated into basal and apical portions. Morphometric measurement was applied to the characterization of each ontogenetic phase. Tissue water content in the leaves was defined, and CAM detected through PEPC enzymatic assaying, MDH, and organic acid (citric and malic) quantification. Tank-2 plants presented more than double the capacity to store water, when compared to Tank-1 plants. Whereas atmospheric plants underwent the greatest leaf-water loss (around 50%), the loss was less in those with tanks (around 15%). Significant nocturnal malic acid accumulation in plants in all the ontogenetic phases, placed in evidence plant competency for CAM expression, independent of the stage of development. Likewise, significant malic acid accumulation in both young leaves and more mature ones indicated their capacity for CAM expression in the three stages of development chosen for the present study. Thus, in the experiments carried out, it can be presumed that the most important factor for CAM expression in G. monostachia plants is leaf-tissue water content, and not ontogeny. Atmospheric plants presented the highest water loss (around 50%), which was concomitant with CAM expression. On the other hand, in the apical regions of Tank-2 plants, there was a drop of 7% in water content with nocturnal malic acid accumulation in stage-1 leaves, and a loss of 12% in tissue water in those in stage 2 and 3, with the consequential CAM inhibition. There is every indication that water-transport in tank plants undergoing water-stress occurs from more mature leaves to those younger. Apparently the more active metabolism in young G. monostachia atmospheric plants, even under conditions inducing low leaf-tissue water content, indicates a certain degree of drought tolerance. On the contrary, although this capacity in tank plants appears to be less accentuated, the tank phase is apparently more related to strategies for avoiding the effects of drought
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Clark, Fernando José König. "Análise dos otólitos Sagittae de Athrinella brasiliensis (QUOY & GAIMARD, 1825) em estuários com diferentes gradientes de salinidade no Nordeste do Brasil." Universidade Estadual da Paraíba, 2018. http://tede.bc.uepb.edu.br/jspui/handle/tede/3045.
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Conselho Nacional de Desenvolvimento Científico e Tecnológico - CNPq
The inner ear of teleostean fishes has internally hair cells which in contact with otoliths is responsible for orientation and balance and hearing, providing positioning and movement senses. The semicircular canals house the three otoliths suspended in liquid, connected to the optical membranes, being sagittae, used as chronological structure because they are not reabsorbed after their formation by the deposition of calcium carbonate, creating rings making the analysis of this structure on studies of aging and the use of the habitats in which they pass part of their life cycle. Dependent on genetic and environmental factors, the otolith forms are species specific, thus functioning as markers of both the different environmental conditions the fish are subjected to and the characteristic phylogenetic patterns found in the families to which each species belongs. For this, estuaries are important coastal environments for the initial stages of fish life, which provide them with better feeding conditions. However, fish are submitted to environmental factors governed in part by hydrological conditions, which influence salinity, temperature, turbidity and primary productivity. Therefore, the study of t he shape of otoliths is useful for the identification of Atherinella brasiliensis populations, a species with wide distribution in shallow water environments of the Brazilian coast, forming large schools, and important for the beginning of the trophic chains. Considering this, it was sought to understand how the development of otoliths in two distinct environments, mainly in relation to the salinity gradient, and between the juvenile and adult phases, comparing the populations of these environments and thus seeking a better ecological understanding for future projects. management. A total of 1,190 individuals (3,357 g) were captured, distributed between 633 to the Mamanguape estuary and 457 to the Tubarão estuary. The sagittae otoliths presented a general elliptic, concave-convex shape. The morphometric parameters were higher for the upper zones of the studied environments. The indices of ellipticity and shape factor were higher in the upper estuary and in the hypersaline estuary, and differences were observed only for juveniles and adults, with circularity and rectangular indexes being higher among juveniles.
O ouvido interno nos peixes teleósteos, responsável pela orientação e equilíbrio e audição, possui internamente grupos de células pilosas, que em contato com os otólitos, proporcionam funções de posicionamento e movimento. Os canais semicirculares alojam os três otólitos suspensos em líquido, ligados às membranas óticas, sendo o sagittae, usado como estrutura cronológica e para a audição dos peixes. Por não serem reabsorvidos após sua formação pela deposição de carbonato de cálcio, e com a criação de anéis, a analise dessa estrutura possibilita estudos sobre a idade e sobre a utilização dos habitats nos quais passam parte do seu ciclo de vida. Dependentes de fatores genéticos e ambientais, as formas dos otólitos são específicas de cada espécie, assim funcionando como marcadores tanto de condições ambientais diferentes as quais os peixes estão submetidos, quanto a padrões filogenéticos característicos encontrados nas famílias as quais cada espécie pertence. Para tal, os estuários são importantes ambientes costeiros para o ciclo de vida dos peixes, que lhes propiciam melhores condições de alimentação. Entretanto, os peixes são submetidos a fatores ambientais regidos em parte por condições hidrológicas, o que influencia na salinidade, temperatura, turbidez e produtividade primária. Assim sendo, o estudo da forma dos otólitos, é útil para identificação de populações de Atherinella brasiliensis, espécie com ampla distribuição em ambientes de águas rasas do litoral brasileiro, formadora de grandes cardumes, e importante para o início das cadeias tróficas. Visto isso, buscou-se entender como desenvolvimento dos otólitos frente a dois ambientes distintos, principalmente, quanto ao gradiente de salinidade, e entre as fases juvenil e adulta, comparando as populações desses ambientes e assim, buscando uma melhor compreensão ecológica para futuros projetos de manejo. Foram capturados 1.090 indivíduos (3.357g), distribuídos entre 633 para o estuário do rio Mamanguape, e 457 para o estuário rio Tubarão. Os otólitos sagittae apresentaram forma geral elíptica, côncavo-convexa. Os parâmetros morfométricos foram maiores para as zonas superiores dos ambientes estudados. Os índices de forma elipsidade e fator de forma foram maiores na zona superior do estuário positivo e no estuário hipersalino, e diferenças foram observadas apenas para juvenis e adultos, sendo os índices, de circularidade e retangularidade maiores entre os juvenis.
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Augusta, Bruno Gonçalves. "Revisão sistemática e ontogenética dos materiais cranianos atribuídos ao gênero Mariliasuchus (Crocodyliformes, Notosuchia) e suas implicações taxonômicas e paleobiológicas." Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/38/38131/tde-30062014-144530/.
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Mariliasuchus amarali Carvalho & Bertini 1999 é um crocodilomorfo Notosuchia do Cretáceo da Bacia Bauru. Este táxon possui um registro fóssil relativamente comum, e diversos espécimes (incluindo animais juvenis) são conhecidos. Portanto, ele representa um dos poucos táxons fósseis que permitem uma análise ontogenética, e seu desenvolvimento foi comparado com o do gênero Caiman (incluindo C. latirostris, C. crocodilus e C. yacare), um crocodilomorfo atual de ampla distribuição pela América do Sul. Foram empregadas as seguintes metodologias para comparação das trajetórias ontogenéticas dos táxons fóssil e atual: descrição qualitativa, morfometria linear e morfometria geométrica. Os dados obtidos destacaram trajetórias ontogenéticas comuns aos dois táxons, que foram interpretadas como o resultado de um padrão plesiomórfico aos Crocodyliformes, e distintas trajetórias ontogenéticas que foram relacionadas, principalmente, a diferentes adaptações ecomorfológicas. A ocorrência de tendências ontogenéticas como a manutenção de uma fenestra supratemporal de grandes proporções ao longo da ontogenia, a expansão anterior do articular e do côndilo mandibular do quadrado, o aumento na espessura da camada de esmalte dentário e a alometria positiva das fenestras infratemporal e mandibular sugerem que Mariliasuchus amarali aumentava gradativamente seu controle e capacidade de processamento alimentar ao longo de seu desenvolvimento. A análise ontogenética também mostrou fortes evidências de que o espécime UFRJ-DG 56-R, interpretado por Nobre et al. (2007a) como uma nova espécie dentro do gênero Mariliasuchus (M. robustus), é na verdade um indivíduo de M. amarali em avançado estágio de desenvolvimento e não uma nova espécie. O espécime MZSP-PV 760 é descrito pela primeira vez no presente trabalho. Suas características anatômicas sugerem que o mesmo não é um indivíduo juvenil de Mariliasuchus, como pensado anteriormente, mas parece estar relacionado ao clado que inclui ambos M. amarali e Adamantinasuchus navae (outro crocodilomorfo da Bacia Bauru). MZSP-PV 760 representa o mais jovem crocodilomorfo pós-embrionário já descrito para o Cretáceo de Gondwana. Uma reanálise da dentição altamente heterodonte em M. amarali mostrou a ocorrência de um novo morfótipo dentário (pré-molariforme), descrito pela primeira vez no presente trabalho. Uma coroa de cada morfótipo dentário foi extraída do espécime MZSP-PV 813 para análise da microanatomia do esmalte dentário e do padrão de organização dos cristais de esmalte, descritos pela primeira vez para um Notosuchia. A descrição de um novo morfótipo dentário representa uma inesperada adição para uma já complexa condição heterodonte em M. amarali, corroborando com a hipótese de OConnor et al. (2010) de que os Notosuchia podem ter ocupado nichos ecológicos e ecomorfoespaços, durante o Cretáceo do Gondwana, tão complexos quanto os de mamíferos.Mariliasuchus amarali Carvalho & Bertini 1999 is a notosuchian crocodyliform from the Cretaceous of Bauru Basin (Brazil). This taxon has a fossil record that is relatively common, and several specimens (including juveniles) are known. Therefore, it represents one of the few fossil taxa that allows an ontogenetic approach, and its development was compared with the genus Caiman (including C. latirostris, C. crocodilus and C. yacare), a widespread South American crocodyliform. I used the following methodologies for the comparison of the ontogenetic trajectories of the fossil and living taxa: qualitative description, traditional morphometrics and geometric morphometrics. The data highlighted common ontogenetic trajectories that were interpreted as the result of a plesiomorphic pattern for Crocodyliformes, and distinct ontogenetic trajectories that were related mainly to different ecomorphological adaptations. The occurrence of ontogenetic trends as the retention of a large supratemporal fenestra along the ontogenetic development, the anterior expansion of the articular and the articular condyle of the quadrate, the thickening of the enamel cap in the teeth crowns, and the positive allometry of both infratemporal and mandibular fenestrae, suggest that Mariliasuchus amarali gradually increased its control and capacity of food processing along its ontogeny. The ontogenetic analysis also provided compeling evidence that specimen UFRJ-DG 56-R, interpreted by Nobre et al. (2007a) as a new species of the genus Mariliasuchus (M. robustus), is actually an individual of M. amarali in an advanced stage of development rather than a new species. Specimen MZSP-PV 760 is described for the first time here. Its anatomical characteristics suggest that this individual is not a juvenile specimen of Mariliasuchus amarali, as previously thought, but rather appears to be related to the clade that includes both M. amarali and Adamantinasuchus navae (another Bauru Basin crocodyliform). MZSP-PV 760 represents the youngest post-hatchling crocodyliform described for the Cretaceous of Gondwana. A reevaluation of the highly heterodont dentition of M. amarali showed the occurrence of a new tooth morphotype (premolariform), described here for the first time. A crown from each tooth morphotype was extracted from the specimen MZSP-PV 813 to perform an analysis of the enamel microanatomy and organizational patterns of enamel crystallities, described for the first time within Notosuchia. The description of a new tooth morphotype represents an unexpected addition to an already complex heterodont condition in M. amarali, adding to OConnor et al.s (2010) hypothesis that Notosuchia could have filled complex niches and ecomorphospaces during the Cretaceous of Gondwana similar to the ones occupied by mammals.
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Mifsud, William. "Studies on the ontogeny of the mammalian germ line." Thesis, University of Cambridge, 2011. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.609789.
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Armelloni, Enrico Nicola. "Ontogeny of upper beak in Octopus vulgaris (Cuvier, 1797)." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2017. http://amslaurea.unibo.it/14651/.
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The beak is a fundamental component of the digestive system and is also used for age estimation in Octopus vulgaris. Nevertheless, the embryonic development of the beak is still largely unexplored. With this aim, upper jaws were observed and photographed using a wet coverslip with Differential Interference Contrast microscope. Pictures were analysed to obtain the measurements of upper jaws. We described the successive embryonic phases, and the beak structural features to assess the presence of pre-hatching increments in Lateral walls and the Rostrum. Three main phases were identified during the embryonic beak ontogeny. In a first phase the beak is a rudiment. The second phase begins when appears the layer originating the Hood. The third phase is characterized by the begin of sclerotization process. The Rostrum starts to be visible when embryos assume the hatching competence and the accuracy of the ageing method using the Rostrum surface was confirmed. On the contrary, several increments are visible on the lateral walls and none of them is related to specific embryonic event. A morphometric analysis was carried out, exploring similarities between growth pattern of different regions of the beak. In terms of growth rate, in the Rostrum the relative growth rate decreased in late ontogeny suggesting that modifications could be related with hardness, rather than size increase.In a second experiment the influence of temperature on beak growth was analysed. Using egg clusters reared at different temperatures, overall sizes of beaks and similarities between growth pattern of different beak regions are compared for a better understanding of the environmental effect in the beak development. In terms of beaks’ overall size, individual variability increased in the temperature conditions other than 19° and beaks reared at warm temperature, which were smaller than the rest of individuals. A relationbetween growth rate and areas of beak and effect of temperature was not confirmed.
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Vennerholm, Linn. "Ontogeny of personality in red junglefowl chicks, Gallus gallus." Thesis, Linköpings universitet, Institutionen för fysik, kemi och biologi, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-78996.
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Many studies have been performed on animals to study their behavior, but not as many on the development of behavior, and not yet on chickens. Therefore, 42 red junglefowls were tested in three Novel Arena, Novel Object and Tonic Immobility tests to investigate the ontogeny of personality. Several behaviors were stable over time in the Novel Arena and Novel Object tests, and are a part of the bird’s personality, while other behaviors were plastic. The stability of the behaviors increased over time. The decrease in duration of the Tonic Immobility can be due to decreased stress during the length of the study. The study showed that personality can be detected early in a chicken’s life, even though a lot of the observed behaviors change. Further studies are needed to figure out duration of the stability and why certain behaviors are stable.
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Suddendorf, Thomas. "On the ontogeny and phylogeny of the representational mind." Thesis, University of Auckland, 1998. http://wwwlib.umi.com/dissertations/fullcit/9824385.
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This thesis proposes a theory for fundamental aspects of the evolution and development of the representational mind. Building on Perner's (1991) theory of representational development, it is suggested that mind evolved from the ability to represent current reality (primary mind) to further entertain secondary representations of hypothetical content (collating mind) to finally represent representational relations themselves (metamind). In child development these transitions can be observed by about 18 months and by about 42 to 48 months. In comparative analysis only the great apes show signs of a collating mind. Young children and great apes can, for example, pretend, consider a limited future and past, solve problems by insight, and consider others' basic mental states. By about age four children begin to show evidence for metarepresentation in their ability to pass theory-of-mind tasks. At about the same age they also gain considerable executive control which, together with metarepresentation, is the key cognitive advance of metamind. Empirical evidence suggests that various skills co-develop with metamind and the thesis includes four studies that investigate such associations. It was found that gestural representation with imaginary objects and the generation of creative problem solutions were robustly correlated with theory-of-mind measures. These results substantiate the claim for a domain-general change in cognitive ability by about age four. Understanding delayed video feedback, however, was not found to correlate with such measures and it is questioned whether delayed feedback tasks measure an extended sense of self as has been proposed (Povinelli, 1995; Suddendorf & Corballis, 1997). Great apes, while showing evidence for a collating mind, have not yet provided any convincing evidence for metamind. It is thus suggested that metamind developed after the split from the line that led to modern chimpanzees about five million years ago. Metamind, it is argued, was a prime mover in human phylogeny and is a crucial step in human ontogeny.Subscription resource available via Digital Dissertations only.
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Raine, Jason Charles. "Ontogeny of thyroid function in rainbow trout, Oncorhynchus mykiss." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp03/MQ31863.pdf.
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Deng, Xing-Fei. "Myocardial a1-adrenoceptor subtypes : ontogeny, signaling and receptor interactions." Thesis, McGill University, 1997. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=34715.
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The overall objective of this project was to study the ontogeny and receptor signaling of myocardial alpha1adrenoceptor (alpha1AR) subtypes. It was found that alpha1AR-mediated inotropic effects and phosphatidylinositide (PI) turnover in neonatal and adult rat myocardium are mediated by different receptor subtypes. In neonatal rats, alpha 1AAR play a predominant role, although both alpha1AAR and alpha 1BAR are present in approximately equal amount as assayed by ligand binding; however, both alpha1AAR and alpha1BAR contribute to the positive inotropic response of adult rat myocardium. alpha1D AR are not functionally expressed in neonatal rat hearts but may play a minor role in adult myocardium. On the other hand, alpha1DAR are the predominant subtypes mediating the contractile response of the rat aorta to alpha1AR agonists.alpha1AR-mediated positive inotropic effect seems to be mediated by Ca2+-independent PKC isoforms (nPKC); the activation of Ca2+-dependent isoforms (cPKC) may inhibit the myocardial contraction. This inference is suggested by the following data: (1) phenylephrine-induced positive inotropic response was potentiated by DAG kinase inhibitor R59949, and inhibited by PKC inhibitor BIM but not by selective cPKC inhibitor G0 6976; (2) phenylephrine caused a translocation of nPKC (delta and epsilon) but not of cPKC(alpha); (3) simultaneous activation of both cPKC and nPKC by PDBu and selective activation of cPKC by thymeleatoxin resulted in negative inotropy, which was blocked by BIM as well as Go 6976.
In neonatal hearts, inactivation of alpha1BAR by CEC potentiated alpha 1AAR-mediated effects on PKC activation, Ca2+ signaling and hypertrophy. Based on these data, I present a model describing a possible mechanism by which alpha1BAR antagonize alpha1AAR-mediated effects via negative coupling to Ca2+ channels. This antagonistic relationship between alpha1AAR and alpha1BAR may be required physiologically for normal alpha1AR-mediated myocardial responses.*
*Please refer to dissertation for diagram.
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Goff, Lindsey Kate. "Cluster of differentiation 45 isoforms and murine thymic ontogeny." Thesis, Open University, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.333266.
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Griffin, P. "The ontogeny of the Fc receptor in rat intestine." Thesis, University of Southampton, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.373972.
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Tuncgenc, Bahar. "Movement synchrony, social bonding and pro-sociality in ontogeny." Thesis, University of Oxford, 2016. https://ora.ox.ac.uk/objects/uuid:b766e5a0-9cbe-4af2-b545-3e87c3d6d573.
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Human sociality, with its wide scope, early ontogeny and pervasiveness across cultures, is remarkable from an evolutionary perspective. We form bonds with other individuals and live in large social groups. We help, empathise with and share our resources with others, who are unfamiliar and genetically unrelated to us. It has been suggested that interpersonal coordination and rhythmic synchronisation of movements may be one proximate mechanism that enables such widespread human sociality and facilitates cooperation. In the last decade, considerable research has examined the effect of movement synchrony on social bonding and cooperation. However, when this thesis started, there was virtually no experimental study investigating the ontogeny of the movement synchrony-social bonding link, which is proposed to have deep evolutionary roots and important, long-lasting consequences in social life. This thesis aims to investigate the effects of movement synchrony on social bonding and cooperative behaviour across different time points in ontogeny. Three experimental studies were conducted examining infancy, early childhood and middle childhood. Each study explored a different aspect of social bonding and cooperation based on the motor, social and cognitive developments that mark that age group. Study 1a found that at 12 months of age, infants prefer individuals who move in synchrony with them, when the individuals are social entities, but not when they are non-social. Study 1b showed no preferences for synchrony at 9 months in either social or non-social contexts, however. Study 2 revealed that in early childhood, performing synchronous movements actively with a peer facilitates helping behaviour among the children, as well as eye contact and mutual smiling during the interaction. Finally, Study 3 showed that the social bonding effects of movement synchrony applied to inter- group settings and that performing synchronous movements with out-groups increased bonding towards the out-group in middle childhood. This thesis followed an interdisciplinary, integrative and naturalistic approach, where (i) literature from a wide range of disciplines motivated and guided the present research; (ii) links between motor, social and cognitive aspects of development, which are often investigated separately, are formed; and (iii) the experiments were designed in ways that represent the real-life occurrences of the investigated phenomena. The current findings provide the first substantial evidence that movement synchrony facilitates social bonding and cooperation in childhood and thereby provides a foundation for future research.