Made available in DSpace on 2015-09-25T12:22:16Z (GMT). No. of bitstreams: 1 PDF - Adna Ferreira da Silva.pdf: 2742100 bytes, checksum: 5eac481e80f94ac80556b01d46ce00a4 (MD5) Previous issue date: 2014-02-25 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Medium scale variations in estuarine fish assemblages can be modulated by seasonal fluctuations in environmental conditions and biotic factors, but short scale variations in photoperiod and tidal cycles are also important. They can change the availability of food resources and shelter against predators and, consequently, lead to changes in fish assemblage attributes and fish diets. The effect of these short scale variations in the ichthyofauna have been investigated in several ecosystems, but their influence on fishes occurring in mudflats is poorly known. The main goal of this work is to assess the effects of temporal variation of short (diurnal and tidal) and medium (wet and dry seasons) scales in the species composition, abundance, diversity and trophic ecology of the ichthyofauna in a mudflat of the Mamanguape River estuary (Paraiba state, Northeast Brazil). Fishes were caught using beach seine hauls and the sampling design took into account the photoperiod, tidal and hydrological cycles. A total of six field sampling surveys were conducted in 2012 along the wet (May, June and July) and dry (October, November and December) seasons. In each field survey three beach seine hauls were employed in each of eight different time periods distributed along the 24h cycle. A total of 6,222 and 66 fish species were captured, being Rhinosardinia bahiensis, Lycengraulis grossidens and Eucinostomus melanopterus the most abundant ones. The analysis along the photoperiod revealed higher numerical abundance in the diurnal period, especially at midday (12:00), whereas species richness and diversity were higher in the nocturnal period, mainly at late night (2:00) and midnight (00:00). These assemblage attributes also changed in relation to tide, but they did not showed statistically significant differences. In order to investigate patterns in food habits of the studied fish fauna, the stomach content of 3,630 individuals belonging to 20 species were analyzed, which were selected based on their abundance and morphological diversity. The dominant pattern of feeding activity was diurnal and most species showed seasonal (wet/dry) and short (day/night) temporal variations in their diet, including ontogenetic diet changes. These variations were related to the feeding activity patterns (diurnal, nocturnal and/or crepuscular) of the fishes and to morphological changes acquired by the individuals during their increment in body size. A total of nine trophic guilds were observed, with Zooplancton Consumers (CZOO) showing the greatest number of fish species. The prevalence of CZOO occurred due to the high capture of juveniles, which could be explained by the fact that these habitats are considered important recruitment and as nursery areas since they provide essential resources in the early phase of their life cycle. Short scale variations in the structure and diet of the ichthyofauna observed in the current work were related to the feeding behavior and trophic ecology, whereas medium scale variations were attributed to variations in fish recruitment patterns. / Variações de médio prazo que ocorrem nas assembleias de peixes estuarinos podem ser reguladas por flutuações sazonais nas condições ambientais e por fatores bióticos. Entretanto, variações de curta escala, como os ciclos das marés e fotoperíodo, também são importantes na medida em que podem alterar a disponibilidade de recursos alimentares e abrigo contra predadores e, desse modo, acarretar em mudanças nos atributos das assembleias e na dieta das espécies. O efeito dessas variações de curta escala sobre a ictiofauna tem sido investigado em vários ecossistemas, porém pouco se conhece sobre sua influência nos peixes que habitam as planícies de maré. O presente trabalho tem como objetivo principal avaliar os efeitos temporais de curta (diurnal e maré) e média duração (estações de chuva/seca) na composição de espécies, abundância, diversidade e ecologia trófica da ictiofauna numa planície de maré no estuário do rio Mamanguape (PB). Os peixes foram capturados com rede de arrasto de praia do tipo picaré através de amostragens realizadas levando em consideração o fotoperíodo, regime de maré e regime hidrológico. Foram realizadas seis coletas compreendidas nas estações de chuva (maio, junho e julho) e seca (outubro, novembro e dezembro) do ano de 2012, sendo que durante cada uma foram realizadas três arrastos em oito horários distintos ao longo do ciclo de 24h. Foram capturados 6.222 indivíduos distribuídos em 66 espécies, sendo que Rhinosardinia bahiensis, Lycengraulis grossidens e Eucinostomus melanopterus foram as mais abundantes. A analise do fotoperíodo indicou maiores abundâncias numérica no período diurno, especialmente ao meio-dia (12:00), enquanto a riqueza e diversidade foram maiores no período noturno, principalmente na madrugada (02:00) e meia-noite (00:00). Esses atributos também oscilaram em relação à maré, porém não apresentaram diferenças significativas. Para verificações de padrões quanto ao hábito alimentar da assembleia de peixes investigada, foi analisado o conteúdo estomacal de 3.630 indivíduos pertencentes a 20 espécies, escolhidas com base na abundância e diversidade morfológica. A maioria das espécies demonstrou variação temporal de médio (chuva/seca) e curto (dia/noite) prazo e também ontogenética na dieta, sendo que o padrão de atividade alimentar predominante foi o diurnal. Essas variações foram atribuídas ao padrão de atividade alimentar das espécies (diurno, noturno e/ou crepuscular) e às mudanças morfológicas adquiridas pelos indivíduos com o incremento em tamanho. Um total de nove guildas tróficas foi observado, com Consumidores de Zooplâncton (CZOO) apresentando o maior número de espécies. Essa predominância de CZOO ocorreu devido à grande captura de juvenis, visto que, estes ambientes são considerados importantes zonas de recrutamento e berçário de peixes, pois fornecem recursos fundamentais nesta fase da vida. As variações de curta duração na estrutura e dieta da ictiofauna observadas no presente trabalho foram relacionadas ao comportamento da atividade alimentar e ecologia trófica, enquanto as de média duração foram atribuídas as variações nos padrões de recrutamento das espécies.

La mélatonine, hormone "donneuse de temps de l’organisme", en plus de sa synthèse principale dans la glande pinéale est produite dans la rétine où sa régulation et ses fonctions restent partiellement connues chez les mammifères. Le but de mon projet a été de caractériser l’expression temporelle et spatiale de la mélatonine et d’examiner son rôle potentiel dans la physiopathologie rétinienne. Une première partie a révélé au moins deux sites de production de la mélatonine dans la rétine : une synthèse nocturne de l'hormone dans les photorécepteurs de type cône ainsi qu'une production diurne dans les cellules ganglionnaires. Nos résultats ont démontré que la mélatonine peut agir par l'intermédiaire de son récepteur nommé MT1, localisés dans chacune des trois couches rétiniennes. Une seconde partie a mis en évidence que la mélatonine augmente la survie des photorécepteurs chez les rongeurs âgés en modulant l'activation de la voie de survie cellulaire via ses récepteurs MT1 et MT2. / Melatonin, a major hormonal "Zeitgeber" in the body, is produced in the pineal gland as well as the retina. In mammals its regulation and functions in this tissue are only partially understood. The aim of my project was to characterize the temporal and spatial expressions of melatonin as well as its potential roles in retinal physiopathology. In the first part, we identified the timing and sites of melatonin production. Notably, nocturnal synthesis occurs in the cones while diurnal production is seen in the ganglion cells. Our work also establishes that melatonin can act via its MT1-type receptors localized in the three retinal nuclear layers. The second axis demonstrated that melatonin increases photoreceptors viability via its receptors during the course of aging by modulating activation of an intracellular survival pathway.

abstract: Stress in individuals presents in various forms and may accumulate across development to predict maladaptive physical and psychological outcomes, including greater risk for the onset of internalizing symptoms. Early life stress, daily life experiences, and the stress response of the hypothalamic-pituitary-adrenal (HPA) axis have all been examined as potential predictors of the development of psychopathology, but rarely have researchers attempted to understand the covariation or interaction among these stress domains using a longitudinal design when looking at the influence of stress on internalizing psychopathology. Further, most research has examined these processes in adulthood or adolescence with much less attention given to the influence of these dynamic stress pathways in childhood. Guided by the biopsychosocial model of stress, this study explored early life stress, daily life stress, diurnal cortisol (cortisol AM slope), and internalizing symptoms in a racially/ethnically and socioeconomically diverse sample of twins participating in an ongoing longitudinal study (N=970 children; Arizona Twin Project; Lemery-Chalfant et al. 2013). An additive model of stress and a stress sensitization framework model were considered as potential pathways of stress to internalizing symptoms in middle childhood. Based on a thorough review of relevant literature, it was expected that each stress indicator would individually predict internalizing symptoms. It was also predicted that early life stress would moderate the associations between diurnal cortisol and internalizing symptoms, as well as daily life stress and internalizing symptoms. Multilevel modeling analyses showed that early life stress and cortisol AM slope, but not daily life stress, predicted internalizing symptoms. Early life stress did not moderate the associations between daily life stress and internalizing symptoms or cortisol AM slope and internalizing symptoms. Results support independent additive contributions of both physiological stress processes and early life parental stressors in the development of internalizing symptoms in middle childhood. Future investigation is needed to better understand the sensitizing effects of early parental life stress during this developmental stage. / Dissertation/Thesis / Masters Thesis Psychology 2020

The graduation theses theme was to determinate changes of initial activity, total activity and Rubisco enzyme content in spinach leaves. Ascertained activities and Rubisco enzyme content were determined from extracts of spinach leaves, which were collected during two distinctively climatic different days. Both activities were determined by spectrometric method and content of enzyme Rubisco by SDS-PAGE method. The findings were compared with findings determined in earlier done works.

京都大学 / 0048 / 新制・課程博士 / 博士(理学) / 甲第19168号 / 理博第4108号 / 新制||理||1591(附属図書館) / 32160 / 京都大学大学院理学研究科地球惑星科学専攻 / (主査)准教授 重 尚一, 准教授 林 泰一, 教授 余田 成男 / 学位規則第4条第1項該当 / Doctor of Science / Kyoto University / DGAM

No description available.

Abstract available through the Infant Behavior & Development: Special ICIS Issue.

Lipid droplets (LDs) are organelles with many functions in cells and numerous protein interactors facilitate their biogenesis, maintenance, and turnover. The mammalian lipase responsible for LD turnover during lipophagy, LipA, has two candidate homologs in Arabidopsis: MPL1 and LIP1. One or both of these plant homologs may function in a similar manner to mammalian LipA, providing an LD breakdown pathway. To test this hypothesis, wild type (WT) Arabidopsis plants, MPL1 over-expressing (OE) mutants, and T-DNA insertion mutants of MPL1 (mpl1) and LIP1 (lip1) were examined for LD phenotypes in normal conditions and in environments where LD numbers are known to fluctuate. Plants to be imaged by confocal microscopy were exposed to heat stress and wounding to increase LD accumulation, senescence was induced in leaves to deplete lipids, and LDs were imaged throughout the day/night period to observe their diurnal regulation. The mutation of both MPL1 and LIP1 lead to an increase in LDs within the leaf mesophyll cells, although the spatial distribution of the LDs differed between the two mutants. mpl1 mutants had disrupted diurnal regulation of their LDs, but lip1 mutants did not. Alternately, lip1 mutants retained LDs during dark-induced senescence, and mpl1 mutants did not. Together these results suggest that MPL1 and LIP1 are likely both important for LD dynamics; however they appear have roles in different aspects of LD accumulation and turnover.

No description available.

No description available.