Please read the abstract in the section 00front of this document / Dissertation (MSc (Genetics))--University of Pretoria, 2007. / Genetics / unrestricted

Orientadores: Narcizo Marques de Souza Neto, Flávio César Guimarães Gandra / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Física Gleb Wataghin / Made available in DSpace on 2018-08-26T19:21:43Z (GMT). No. of bitstreams: 1 Reis_RicardoDonizethdos_D.pdf: 10140891 bytes, checksum: 060b8807511ae67be03dba829dddacaf (MD5) Previous issue date: 2015 / Resumo: Os resultados apresentados nesta tese mostram a potencialidade do uso das técnicas de espectroscopia de absorção de raio X no estudo das hibridizações (4f,5f )/(5d,6d) em compostos intermetálicos ajudando no entendimento de diversos fenômenos físicos. Na primeira parte do trabalho utilizamos as técnicas de espectroscopia para estudar o comportamento da valência e do magnetismo no composto de EuPt2Si2 quando submetido à pressão. Ao contrário do previamente reportado na literatura nossos resultados mostram que o composto de EuPt2Si2, encontra-se nas vizinhanças de um ponto crítico quântico de flutuação de valência, e a valência do íon de Eu, que é de 2.2 ã pressão ambiente, aumenta com o incremento da pressão se tornando 3+ para pressões maiores do que 15 GPa. A mudança de valência diminuiu o número de íons magnéticos da amostra o que provoca um colapso do seu momento magnético. Nossos dados suportados por cálculos de densidade de estados eletrônicos mostram que o processo de transição de valência ocorre com uma transferência de carga entre os níveis 4f e 5d do Európio, acompanhado de uma maior localização dos orbitais 5d do Eu, fazendo com que as cargas inicialmente compartilhadas pelos íons de Eu/Pt/Si se localizem no orbital 5d do Eu. Na segunda parte desta tese nós mostramos, até nosso conhecimento, os primeiros resultados de dicroísmo circular magnético de raios X (XMCD) nas bordas L2,3 do Urânio. Foram estudados os compostos de UM2(M=Ga,Ge) e UX(X=Te,Se) para os quais foi observada uma gigante contribuição quadrupolar nos espectros de dicroísmo na borda L3. Descrevemos uma metodologia associando a técnica de dicroísmo circular magnético com simulações da estrutura eletrônica usando teoria do funcional densidade (DFT), para estudar o grau de hibridização entre os orbitais 5f-6d e obter informações a respeito do caráter itinerante/localizado do magnetismo de cada um dos compostos. Por fim, a seletividade ao elemento químico da técnica de XMCD foi aplicada no estudo do magnetismo dos compostos de UCu2Si2 e UMn2Si2. A partir dos espectros de XMCD nas bordas L3 do Urânio e K do Cu e do Mn, mostramos que ao contrário do previamente reportado na literatura, tanto o Urânio como os metais 3d nesses materiais apresentam um momento magnético não nulo e que as hibridizações entre os níveis 5f e 3d regulam as propriedades magnéticas nestes dois materiais. Além disso, mostramos que no composto UCu2Si2 o momento magnético oriundo dos níveis 5f (contribuição quadrupolar do XMCD) é antiparalelo ao momento dos níveis 6d (contribuição dipolar do XMCD) / Abstract: The results reported in this thesis show the potential for the use of X-ray Absorption Spectroscopy (XAS) technique on the study of (4f,5f )/(5d,6d) hybridization in intermetallic compounds aiding the understanding of many physical phenomena. On the first part of this thesis, in order to probe the changes in the valence state and magnetic properties of EuPt2Si2 compound under extreme pressure, x-ray absorption near-edge spectroscopy (XANES) and x-ray magnetic circular dichroism (XMCD) were carried out. The XANES spectrum exhibitx a strong dependence with temperature and pressure. Contrary to previous reports, Eu was found to change the valence with the increase of the pressure from divalent to the trivalent state. The change in valence reduced the number of magnetic ions of the sample which causes a collapse of its magnetic moment. Density functional theory has been applied to give insight into the pressure-induced changes in Eu valence and the magnetic ordering on this compound. In the second part of this thesis we show, to the best of our knowledge, the first results of magnetic circular dichroism in Uranium L2,3 edges. A giant quadrupolar contribution was observed in U-L2,3 edges x-ray magnetic circular dichroism of a few representative Uranium compounds (UGa2, UGe2, UTe and USe). We support the spectroscopic data with density functional theory to assess the degree of 5f -6d electronic hybridization and the degree of itineracy/localization of 5f electrons in each of the compounds. Finally, we use the element and orbital selectivity of XANES and XMCD measurements combined on U-L3 and Cu and Mn K absorption edges to probe the eletronic and magnetic properties of the UMn2Si2 and UCu2Si2 compounds. Our results show that both Uranium and 3d elements present magnetic moment and therefore the 5f /3d hybridization regulates the magnetic properties on these compounds. Furthermore, we show for UCu2Si2 compound the aligment of magnetic moments of U 5f and U 6d orbitals is antiparallel / Doutorado / Física / Doutor em Ciências

Orientador: Anete Pereira de Souza / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-27T05:05:38Z (GMT). No. of bitstreams: 1 Francisco_PatriciaMara_D.pdf: 7911618 bytes, checksum: f90010b3ff20ba6416b899bcfb99b443 (MD5) Previous issue date: 2015 / Resumo: Manguezais são ecossistemas com uma variedade incomum de animais e plantas adaptados às condições de alta salinidade, inundações frequentes e solo lodoso e anaeróbico. Ocorrem em locais onde há o encontro de águas de rios com a do mar. Diversos fatores bióticos e abióticos influenciam os padrões de diversidade de espécies de manguezais, como oceanografia, clima, topografia e condições do solo. A diversidade de plantas de mangue é muito reduzida, quando comparada com outros ecossistemas tropicais. O Brasil possui uma das maiores areas de manguezal do mundo e apresenta três gêneros de angiospermas de mangue. Um deles é Rhizophora, composto pelas espécies Rhizophora mangle, Rhizophora racemosa e, um possível híbrido, Rhizophora harrisonii. O objetivo da presente tese foi isolar e caracterizar locos microssatélites para essas espécies e estimar parâmetros populacionais como fluxo gênico, estruturação populacional, diversidade gênica e tamanho efetivo de população, além de estudar outros aspectos da biologia de Rhizophora, como uma possível zona de hibridação na região norte do país, taxa de cruzamento e o sistema reprodutivo. Com este propósito, foram coletados 318 indivíduos de R. mangle de 11 localidades ao longo da costa brasileira, e 33 indivíduos de R. racemosa e 37 indivíduos de R. harrisonii ambas coletadas de duas localidades no litoral brasileiro. Para identificar e caracterizar locos de microssatélites foram desenvolvidas bibliotecas enriquecidas em microssatélites para as três espécies. Utilizando os marcadores desenvolvidos na presente tese, bem como outros que já publicados, observou-se uma diferença significativa entre as populações no padrão de variação genética. A riqueza de alelos, heterozigosidades esperada e observada foram maiores na região norte. Os resultados sugerem que as espécies de Rhizophora não compõe apenas uma população panmítica ao longo do litoral brasileiro, devido à diferenciação existente entre as regiões norte e sul da costa. A análise do sistema reprodutivo de R. mangle de uma população do estado do Pará, encontramos valores que indicariam um sistema de reprodução misto. Em relação à hibridação contínua, não foram encontradas evidências de hibridação introgressiva entre as espécies de Rhizophora. Concluímos que com os resultados obtidos na presente tese foi possível contribuir para o maior conhecimento genético das espécies de Rhizophora spp. do litoral brasileiro / Abstract: Mangrove are ecosystems with an unusual variety of animals and plants adapted to conditions of high salinity and frequent floods and muddy anaerobic soil. Several abiotic factors influence the patterns of mangrove species diversity, such as oceanography, climate, topographic and soil conditions. The number of mangrove plant species is much reduced compared with other tropical ecosystems. Brazil has the second largest mangrove area in the world and has three genera of mangrove angiosperms. One genera is Rhizophora, composed of Rhizophora mangle, Rhizophora racemosa and a possible hybrid, Rhizophora harrisonii. The aim of this thesis was to isolate and characterize microsatellite loci for these species and estimate population parameters such as gene flow, population structure, genetic diversity and effective population size, and study other aspects of Rhizophora biology, as a possible hybrid zone in the north region of the Brazilian coast, crossing rate and the reproductive system. For this purpose, 318 individuals of R. mangle of 11 locations along the Brazilian coast, 33 individuals of R. racemosa and 37 individuals of R. harrisonii from two locations were collected. To identify and characterize the microsatellite loci, enriched microsatellite libraries for the three species were developed. Using the developed markers, and some others already published, we observed a significant difference between the populations in the pattern of genetic variation. Alleles richness, expected and observed heterozygosity were higher in the north. The results suggest that the species of R. mangle is not only composed of a single panmitic population due to differentiation found among the population from locales north and south of the Brazilian Coast. The reproductive system was evaluated studing a population of R. mangle from the state of Pará and we find values that would indicate a mixed mating system. Regarding the ongoing hybridization, we found no evidence of introgressive hybridization among the species leading to a hybrid species. We concluded that with this results it was possible to contribute to further genetic knowledge of Rhizophora spp. from the Brazilian coast / Doutorado / Genetica Vegetal e Melhoramento / Doutora em Genética e Biologia Molecular

abstract: Spatial resolved detection and quantification of ribonucleic acid (RNA) molecules in single cell is crucial for the understanding of inherent biological issues, like mechanism of gene regulation or the development and maintenance of cell fate. Conventional methods for single cell RNA profiling, like single-cell RNA sequencing (scRNA-seq) or single-molecule fluorescent in situ hybridization (smFISH), suffer either from the loss of spatial information or the low detection throughput. In order to advance single-cell analysis, new approaches need to be developed with the ability to perform high-throughput detection while preserving spatial information of the subcellular location of target RNA molecules. Novel approaches for highly multiplexed single cell in situ transcriptomic analysis were developed by our group to enable single-cell comprehensive RNA profiling in their native spatial contexts. Reiterative FISH was demonstrated to be able to detect >100 RNA species in single cell in situ, while more sophisticated approaches, consecutive FISH (C-FISH) and switchable fluorescent oligonucleotide based FISH (SFO-FISH), have the potential for whole transcriptome profiling at the single molecule sensitivity. The introduction of a cleavable fluorescent tyramide even enables sensitive RNA profiling in intact tissues with high throughput. These approaches will have wide applications in studies of systems biology, molecular diagnosis and targeted therapies. / Dissertation/Thesis / Doctoral Dissertation Chemistry 2019

Cette thèse propose une réflexion autour de la relation entre le dessin animé et le cinéma en prises de vues réelles, en faisant reposer le propos sur l’étude d’une forme cinématographique hybride, présentant un entremêlement ou encore une rencontre entre personnages graphiques et acteurs réels. Cette recherche interroge, du cinéma des premiers temps aux expériences plus contemporaines, l’évolution d’une forme reposant sur une frontière technique constamment mouvante au gré d’innovations technologiques et de perspectives théoriques historiquement variables. En s’intéressant tout autant aux films qu’à leur réception et leur contexte de production, l’objectif est de de mettre à jour et de comprendre les raisons pour lesquelles l’animation se trouve perçue à l’heure actuelle, à la fois comme une forme radicalement différente de la prise de vues réelles, rattachée à une institution qui lui est propre, et à la fois comme une forme potentiellement assimilable au cinéma photographique, en particulier dans le cadre de certains films à effets spéciaux. L’enjeu est de creuser les racinesde cette relation singulière, de cette scission-assimilation comme nous choisissons de la nommer, qui s’explique selon des modalités à la fois historiques, théoriques et esthétiques, et que la forme hybride permet de mettre particulièrement en évidence. Notre objectif est d’analyser, à travers l’évolution de cette forme et l’usage qu’en dévoilent les films, l’émergence d’une séparation plus esthétique, discursive et institutionnelle que véritablement ontologique entre ce que divers mouvements historiques et entreprises théoriques ont pu contribuer à définir, tout au long de l’histoire du cinéma, comme deux régimes de représentation aussi séparés que potentiellement assimilables / This thesis proposes a study about the relation between animated cartoons and live-action cinema. We base it on the study of a hybrid cinematic form, presenting a mix or an encounter between graphic characters and real actors. This research tries to question, from early cinema to more contemporaneous experiments, the evolution of a form resting upon a technical frontier always moving at the whim of technological innovations and theoretical perspectives historically variables. While interesting ourselves as much in the films than in their reception and their production context, the objective is to reveal and understand the reasons why animation is seen, nowadays, equally as a form radically different from live-action, linked to an institution of its own, and equally as a form potentially assimilable to photographic cinema, particularly in the case of films based on special effects. We aim to dig in order to find the roots of this singular relation, of this scission-assimilation aswe chose to name it, that we can explain through historical, theoretical and aesthetical modalities, particularly lighten by the hybrid form. Our goal is to analyze, through the evolution of this form and its use revealed by the films, the emergence of a separation more aesthetical, discursive or institutional than really ontological between what several historical movements and theoretical enterprises have contributed to define, throughout the history of cinema, as two systems of representation as well separated than potentially assimilable

One approach to enabling a larger penetration of renewable sources of energy is the implementation of hybrid power plants. This work presents a process to determine the preliminary optimal configuration of a concentrating solar power-coal hybrid power plant with low solar augmentation, and is demonstrated on a coal power plant in Castle Dale, UT. A representative model is developed and validated against published data for a coal power plant of a different configuration than Hunter Unit 3. The simplifications within the representative model include combining multiple feedwater heaters, combining turbines that operate across the same boundary states, and the mass-average calculation for extraction properties to the combined feedwater heaters. It is shown that the representative model can accurately and consistently simulate a coal power plant. Comparing net power generation and boiler heating estimates from the representative model to the benchmark power plant, the representative model is accurate to within +/- 1% the accepted value from the benchmark power plant. The methods for quantifying solar resource with data from the National Renewable Energy Laboratory are presented with the derivation of an algorithm to simulate a concentrating solar power field arrangement. The solar contribution to electrical power output is estimated using an exergy balance. A simplified financial model is also developed to estimate the solar marginal levelized cost of electricity and payback time using a cash-flow analysis. Estimates for solar resource, solar contribution, and financial performance are consistent with data published by the National Renewable Energy Laboratory or in archival literature. A multi-objective optimization routine is developed consisting of the representative model, the augmentation of solar energy into the solar integration model by means of feedwater heater bypass, solar contribution, levelized cost of electricity, and payback time. Because this study considered complete FWH bypass, higher solar augmentation (>3% of boiler heating) is required for a hybrid design to be considered feasible. However, for higher solar augmentation, the costs are also considerably higher and the financial benefit is insufficient to make any hybrid designs feasible unless a carbon tax is in place. A carbon tax will amplify the financial benefit of hybridization, so optimization results are provided assuming a carbon tax value equivalent to the value used in California's Emissions Trading System (16 USD sh.tn.^-1). The impact of a green energy premium price paid by consumers is also explored in the context of payback time. The resulting optimal design for the Hunter Unit 3 with a carbon tax and no premium is using parabolic trough collector technology at an augment fraction of k=9% to bypass feedwater heater 6. The resulting marginal solar levelized cost of electricity is 9.5 x 10^-4 USD kWh^-1 with an estimated payback time of 25.2 years. This process can be applied to any coal power plant for which operating data and meteorological data are available to evaluate preliminary hybridization feasibility.

Silver nitrate staining, a rapid and efficient method, has proven to be excellent for nucleolar organizing region (NOR) studies in fish. Some fish appear to have only two NOR-bearing chromosomes in their karyo-type, whereas others probably have several. In the present study we analyzed the NORs of Leporinus friderici, a species that, on the basis of previous studies, has been considered as representative of species with NORs carried by a single chromosome pair. The analyses were performed by a combination of three methods, i.e. silver nitrate staining, staining with the GC-specific fluorochrome chromomycin A3, and in situ hybridization with digoxigenin-labeled probes. The results showed that, although more frequent and conspicuous in a single chromosome pair, the NORs of this species are present in multiple chromosomes. Intra- and inter-individual variations observed by the three methods strongly suggest the occurrence of post-zygotic modifications involving NORs. NOR identification in fish, almost exclusively performed by the silver nitrate method, is currently being re-evaluated by methods such as chromomycin A3 staining and in situ hybridization, which may provide important information leading to a better understanding of chromosome evolution in these animals.

Hybridization in plants can be common, may lead to increased genetic variation, and in some instances the formation of new species. For endangered species, hybridization can introduce novel genetic variation and potentially increase genetic diversity. In contrast, hybridization can negatively affect an endangered species or population by introducing maladaptive alleles into locally adapted lineages or lead to the homogenization of once distinct lineages. We used microsatellites, AFLP markers, and morphological data to identify potential hybridization between the endangered Roan Mountain bluet (Houstonia purpurea var. montana) and its commonly occurring congener (H. purpurea var. purpurea). We used these data to clarify the taxonomic relationship of these varieties and to assess population structuring of the Roan Mountain bluet. The results showed that these lineages are distinct and few individuals exhibited admixture in several populations. Additionally, the results showed there is genetic population structure among the remaining populations of H. purpurea var. montana, which is consistent with other mountaintop species. Our results show that Roan Mountain bluet populations should be protected to maintain genetic diversity and monitored to assess future hybridization, and additional studies that comprise a greater population sampling would provide more information.

Recent data suggest novel functional roles for cerebellar involvement in a number of neurologic diseases. Function of cerebellar neurons is known to be modulated by norepinephrine and adrenergic receptors. The distribution of adrenergic receptor subtypes has been described in experimental animals, but corroboration of such studies in the human cerebellum, necessary for drug treatment, is still lacking. In the present work we studied cell-specific localizations of α1 adrenergic receptor subtype mRNA (α1a, α1b, α1d), and α2 adrenergic receptor subtype mRNA (α2a, α2b, α2c) by in situ hybridization on cryostat sections of human cerebellum (cortical layers and dentate nucleus). We observed unique neuron-specific α1 adrenergic receptor and α2 adrenergic receptor subtype distribution in human cerebellum. The cerebellar cortex expresses mRNA encoding all six α adrenergic receptor subtypes, whereas dentate nucleus neurons express all subtype mRNAs, except α2a adrenergic receptor mRNA. All Purkinje cells label strongly for α2a and α2b adrenergic receptor mRNA. Additionally, Purkinje cells of the anterior lobe vermis (lobules I to V) and uvula/tonsil (lobules IX/HIX) express α1a and α2c subtypes, and Purkinje cells in the ansiform lobule (lobule HVII) and uvula/tonsil express α1b and α2c adrenergic receptor subtypes. Basket cells show a strong signal for α1a, moderate signal for α2a and light label for α2b adrenergic receptor mRNA. In stellate cells, besides a strong label of α2a adrenergic receptor mRNA in all and moderate label of α2b message in select stellate cells, the inner stellate cells are also moderately positive for α1b adrenergic receptor mRNA. Granule and Golgi cells express high levels of α2a and α2b adrenergic receptor mRNAs. These data contribute new information regarding specific location of adrenergic receptor subtypes in human cerebellar neurons. We discuss our observations in terms of possible modulatory roles of adrenergic receptor subtypes in cerebellar neurons responding to sensory and autonomic input signals, and review species differences in cerebellar adrenergic receptor expression.

Fluorescence in situ hybridization (FISH) and digital imaging microscopy were modified to allow detection of single RNA molecules. Oligodeoxynucleotide probes were synthesized with five fluorochromes per molecule and the light emitted by a single probe was calibrated. Points of light in exhaustively deconvolved images of hybridized cells gave fluorescent intensities and distances between probes consistent with single mRNA molecules. Analysis of β-actin transcription sites after serum induction revealed synchronous and cyclical transcription from single genes. The rates of transcription initiation and termination and mRNA processing could be determined by positioning probes along the transcription unit. This approach extends the power of FISH to yield quantitative molecular information on a single cell.