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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

Capacidade de combinação de genitores, parâmetros genéticos de aparência e de rendimento de tubérculos e características de qualidade funcional e industrial de clones de batata / Combining ability of genitors, genetic parameters of tuber appearance and yield, and functional and industrial quality characteristics of potato clones.

Cima, Franciele Fatima 26 June 2018 (has links)
Submitted by Gabriela Lopes (gmachadolopesufpel@gmail.com) on 2018-08-02T21:23:57Z No. of bitstreams: 1 TESE_Francieli_Fatima_Cima.pdf: 1522443 bytes, checksum: 765fffef828845aa25396ca45a86542e (MD5) / Approved for entry into archive by Aline Batista (alinehb.ufpel@gmail.com) on 2018-08-16T18:03:42Z (GMT) No. of bitstreams: 1 TESE_Francieli_Fatima_Cima.pdf: 1522443 bytes, checksum: 765fffef828845aa25396ca45a86542e (MD5) / Made available in DSpace on 2018-08-16T18:03:42Z (GMT). No. of bitstreams: 1 TESE_Francieli_Fatima_Cima.pdf: 1522443 bytes, checksum: 765fffef828845aa25396ca45a86542e (MD5) Previous issue date: 2018-06-26 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Batatas com polpa colorida contêm altas concentrações de antioxidantes, incluindo ácidos fenólicos, antocianinas e carotenoides. Esses fitoquímicos apresentam efeitos terapêuticos e promotores da saúde humana, exercendo papel-chave na prevenção e/ou tratamento de doenças crônicas. O crescente interesse nos benefícios à saúde adquiridos através da alimentação tem contribuído para o aumento do consumo dessas batatas “especiais” e crescimento de um mercado especializado. Para atender a demanda desse nicho de mercado é imprescindível o desenvolvimento de cultivares de polpa colorida e, para o rápido progresso, é fundamental a escolha correta dos genitores e procedimentos eficientes de seleção. Nesse sentido, foram desenvolvidos três estudos. O primeiro visou estimar capacidade de combinação de clones de batata de polpa colorida e de polpa creme e amarelo claro para caracteres de aparência externa e interna e de rendimento de tubérculos. Foram avaliadas oito famílias segregantes de batata, em modelo de dialelo parcial (3x3). Verificou-se que há predomínio de efeitos aditivos de genes no controle de caracteres de aparência e de rendimento de tubérculos. O segundo estudo visou estimar parâmetros genéticos de caracteres de aparência externa e interna e de rendimento de tubérculos, e suas implicações na seleção, em uma população híbrida constituída de 12 famílias segregantes para cor da polpa. Os resultados sugerem que pode se aplicar forte pressão de seleção para os caracteres cor da película, cor predominante da polpa, cor secundária da polpa e distribuição da cor secundária, e seleção leve a moderada para profundidade de gemas, formato e aparência geral de tubérculo, na primeira geração clonal. O terceiro estudo visou caracterizar 12 clones de batata de polpa colorida quanto à concentração de compostos bioativos, caracteres de qualidade industrial e de rendimento de tubérculos. Os clones C2715-01-09, C2721-22-09 e C2743-01-09 apresentam elevadas concentrações de compostos bioativos e alta capacidade antioxidante, além de boas características de qualidade de processamento e bom potencial produtivo. O clone C2743-09-09 é o mais produtivo e possui atributos para fritura, porém apresenta teores mais baixos de compostos bioativos e atividade antioxidante mediana. / Colored fleshed potatoes contain high concentrations of antioxidants, including phenolic acids, anthocyanins and carotenoids. These phytochemicals have therapeutic effects and promoters of human health, playing a key role in the prevention and/or treatment of chronic diseases. The growing interest in the health benefits acquired through food has contributed to increase consumption of these "special" potatoes and growth of a specialized market. In order to meet the demand of this market niche, the development of colored fleshed varieties is essential, and for a fast progress it is fundamental the correct parental choice and efficient selection procedures. In this sense, three studies were developed. The first aimed to estimate combining ability of colored fleshed and cream and light yellow fleshed potato clones in the external and internal tuber appearance, and tuber yield. Eight segregating potato families were evaluated using a partial diallel design (3x3). It was verified that there is a predominance of additive effects of genes in the control of tuber appearance and yield traits. The second study aimed to estimate genetic parameters of tuber external and internal appearance and yield traits, and their implications on selection, in a hybrid population consisting of 12 segregating families for flesh color. The results suggest that a high pressure of selection can be applied to the traits color of the skin, predominant color of the flesh, secondary color of the flesh and distribution of secondary color, and mild to moderate selection for bud depth, shape and overall appearance of tuber, in the first clonal generation. The third study aimed to characterize 12 colored flesh potato clones as to the concentration of bioactive compounds, processing quality traits and tuber yield. Clones C2715-01-09, C2721-22-09 and C2743-01-09 present high concentrations of bioactive compounds and high antioxidant capacity, besides good processing quality traits and good yield potential. The clone C2743-09-09 is the most productive and has frying attributes, but presents lower levels of bioactive compounds, and medium antioxidant activity.
22

Contribution à l'étude du rôle de CD146 soluble dans langiogenèse et de l'effet du blocage du récepteur P2Y12 sur la lésion endothéliale lors d'une angioplastie coronaire / Contribution to th study of the role of soluble CD146 in angiogenesis and effect pf P2Y12 receptor blockade on endothelial injury during percutaneous coronary intervention

Harhouri, Karim 20 December 2010 (has links)
Nous avons montré que la molécule recombinante humaine CD146 soluble (rh-sCD146) a un effet chimiotactique et angiogénique sur les cellules dérivées de progéniteurs endothéliaux (PEC) en augmentant leur capacité à migrer, à proliférer et à former des pseudo-capillaires. Des expériences réalisées in vivo sur un modèle d'ischémie de la patte chez le rat ont montré que des injections locales répétées de rh-sCD146 permettent une diminution significative du taux d'auto-amputation des animaux et une augmentation du taux de perfusion sanguin de la patte et de la densité capillaire. Dans une 2ème partie du travail, nous avons montré que l'angioplastie coronaire induit une hausse significative du nombre de cellules endothéliales circulantes (CEC) 6h après l'intervention (H6). Les lésions endothéliales, évaluées par la mesure de la variation du nombre de CEC (H6-H0), sont plus élevées chez les non-répondeurs par rapport aux bons répondeurs au Clopidogrel et sont corrélées à l'index VASP / We showed that the recombinant human soluble CD146 (rh-sCD146) has a chemotactic and angiogenic effect on endothelial progenitor derived cells (EPC) by increasing their ability to migrate, to proliferate and to form pseudo- capillaries. In an in vivo experiments model of ischemia in the rat by femoral artery ligation we showed that repeated local injections of rh-sCD146 for 12 days allows a significant reduction in the rate of animals self-amputation and an increase in the rate of blood perfusion of the leg and in the capillary density. In a second part of the work, we have shown that percutaneous coronary intervention induced a significant rise in circulating endothelial cells (CEC) levels 6h after the procedure (H6). The endothelial injury, assessed by CEC delta-change between H6 and H0, was significantly higher in the high on-treatment platelet reactivity group compared with the good responders to Clopidogrel and correlated with the Vasodilatator-Stimulated Phosphoprotein index
23

Optimization and Longevity of Functionalized Multi-Walled Carbon Nanotube-Enabled Membranes for Water Treatment

White, Madeleine Michael Isabella 01 June 2020 (has links) (PDF)
Water scarcity is a growing concern at the global scale. Large scale water reuse is growing both in necessity and popularity. Before water reuse can be performed efficiently on a large scale or be used for potable supply, even indirectly, contaminants of emerging concern (CECs) will need to be treated at the full scale. Advanced oxidation processes (AOPs) are a form of advanced water treatment capable of treating a wide range of CECs. This study contributes to the growing field of AOPs and more specifically AOPs using ozone combined with functionalized multi-walled carbon nanotubes (MWCNTs). Ozonation of MWCNTs has been found to increase hydroxyl radical production and improve AOP treatment. Novel MWCNT-enabled membranes were used as catalysts for ozonation to degrade the CEC Atrazine. Atrazine is an ozone recalcitrant CEC that is commonly found in herbicides. Atrazine removal results, found using a high-performance liquid chromatograph (HPLC), were inconsistent between membranes constructed using identical procedures. Further analysis using Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopes (SEM), and UV-Vis spectrophotometry was conducted to explore inconsistencies in construction of the membranes which might explain removal inconsistencies and predict membrane longevity. Removal was found to be influenced by filtration time and ozone exposure. Ozone exposure and filtration time influence percent removal because they both affect hydroxyl formation. The membrane test filtration duration, for equal filtered volumes, ranged from under 5 minutes to nearly an hour. It is believed that filtration time inconsistency was due to inconsistent MWCNT loading on the surface of the membranes. Extended exposure to ozone might change the surface chemistry of the MWCNTs on the membrane surface, affecting hydroxyl radical production. Additionally, repeated use of the membrane created surface defects that might reduce the membrane strength. This study found that the lifetime of the membrane is far past what was simulated in lab and further testing must be performed.
24

An Interactive Chemical Equilibrium Solver for the Personal Computer

Negus, Charles H. 20 February 1997 (has links)
The Virginia Tech Equilibrium Chemistry (VTEC) code is a keyboard interactive, user friendly, chemical equilibrium solver for use on a personal computer. The code is particularly suitable for a teaching / learning environment. For a set of reactants at a defined thermodynamic state given by a user, the program will select all species in the JANAF thermochemical database which could exist in the products. The program will then calculate equilibrium composition, flame temperature, and other thermodynamic properties for many common cases. Examples in this thesis show VTEC's ability to predict chemical equilibrium compositions and flame temperature for selected reactions, and demonstrate how VTEC can substitute for and aid in the design of lab experiments, and identify trends in parametric studies. The 1976 NASA Lewis Chemical Equilibrium Code (CEC76) from which VTEC has been adapted uses Lagrangian multipliers to minimize free energy. CEC76 was written for mainframe computer use. Later versions of CEC76, adapted for personal computer use are available for a fee and have a very minimal user interface. / Master of Science
25

Enhancing SAT-based Formal Verification Methods using Global Learning

Arora, Rajat 25 May 2004 (has links)
With the advances in VLSI and System-On-Chip (SOC) technology, the complexity of hardware systems has increased manifold. Today, 70% of the design cost is spent in verifying these intricate systems. The two most widely used formal methods for design verification are Equivalence Checking and Model Checking. Equivalence Checking requires that the implementation circuit should be exactly equivalent to the specification circuit (golden model). In other words, for each possible input pattern, the implementation circuit should yield the same outputs as the specification circuit. Model checking, on the other hand, checks to see if the design holds certain properties, which in turn are indispensable for the proper functionality of the design. Complexities in both Equivalence Checking and Model Checking are exponential to the circuit size. In this thesis, we firstly propose a novel technique to improve SAT-based Combinational Equivalence Checking (CEC) and Bounded Model Checking (BMC). The idea is to perform a low-cost preprocessing that will statically induce global signal relationships into the original CNF formula of the circuit under verification and hence reduce the complexity of the SAT instance. This efficient and effective preprocessing quickly builds up the implication graph for the circuit under verification, yielding a large set of logic implications composed of direct, indirect and extended backward implications. These two-node implications (spanning time-frame boundaries) are converted into two-literal clauses, and added to the original CNF database. The added clauses constrain the search space of the SAT-solver engine, and provide correlation among the different variables, which enhances the Boolean Constraint Propagation (BCP). Experimental results on large and difficult ISCAS'85, ISCAS'89 (full scan) and ITC'99 (full scan) CEC instances and ISCAS'89 BMC instances show that our approach is independent of the state-of-the-art SAT-solver used, and that the added clauses help to achieve more than an order of magnitude speedup over the conventional approach. Also, comparison with Hyper-Resolution [Bacchus 03] suggests that our technique is much more powerful, yielding non-trivial clauses that significantly simplify the SAT instance complexity. Secondly, we propose a novel global learning technique that helps to identify highly non-trivial relationships among signals in the circuit netlist, thereby boosting the power of the existing implication engine. We call this new class of implications as 'extended forward implications', and show its effectiveness through additional untestable faults they help to identify. Thirdly, we propose a suite of lemmas and theorems to formalize global learning. We show through implementation that these theorems help to significantly simplify a generic CNF formula (from Formal Verification, Artificial Intelligence etc.) by identifying the necessary assignments, equivalent signals, complementary signals and other non-trivial implication relationships among its variables. We further illustrate through experimental results that the CNF formula simplification obtained using our tool outshines the simplification obtained using other preprocessors. / Master of Science
26

Cec?lia Meireles: mulher ao espelho, imagin?rio po?tico e metaf?sica do amor em Viagem e Mar Absoluto / Cec?lia Meireles: mulher ao espelho, imagin?rio po?tico e metaf?sica do amor em Viagem e Mar Absoluto

Barreto, La?s Karla da Silva 31 August 2006 (has links)
Made available in DSpace on 2014-12-17T15:06:52Z (GMT). No. of bitstreams: 1 LaisKSB.pdf: 507721 bytes, checksum: f58c6b5475723c6eada0bf483c8f7127 (MD5) Previous issue date: 2006-08-31 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico / En el florescer de la modernidad brasile?a, surge la poes?a de Cec?lia Meireles, revelando la mujer que opta conscientemente por la labor intelectual, por la especulaci?n filos?fica del amor y por la pasi?n de escribir. La lectura de su obra representa um desaf?o a la sensibilidad del estudioso de la literatura. En esta disertaci?n, tratamos de ese trabajo em filigranas que la autora realiza. Nos situamos em las obras Viagem y Mar Absoluto como anclas simb?licas de un discurso que nos remite a la relaci?n del poetar com el pensar. Se inserta, as?, esa po?tica ceciliana en um modo filos?fico plat?nico, trayendo elementos simb?licos, m?ticos, metaf?ricos capaces de remitirnos a las interpretaciones filos?ficas del siglo XX, tal la heideggeriana que entiende la poes?a dentro del principio del eterno juego del ser, que es lo del pr?prio lenguaje. Nuestra preocupaci?n fundamental fue trillar los caminos del erostismo filos?fico y la b?squeda de la autora em transcender la rigidez de los l?mites entre el masculino y el femenino, lanz?ndose em um imaginario po?tico cristiano, reinterpretado neoplatonicamente. Se exponen Mujer y Letras al espejo, velando y desvelando marcas e trazos de identidad. Tal juego especular nos ofreci? elementos po?ticos, est?ticos y una experiencia ceciliana del lenguaje del ser, designio de la poes?a m?sma. De esta nuestra iniciativa, que es tambi?n reflejada y reflexiva, reunimos a las Letras la Filosofia, resaltando que ambas de manera diferente - nos dieron acceso a la construcci?n de esa poes?a en que fulguran la escritura, el ser y la naturaleza metaforizada, caracterizando la multiplicidad de sentidos y la pluralidad de voces del presente y del pasado / Na floresc?ncia da modernidade brasileira, surge a poesia de Cec?lia Meireles, revelando a mulher que opta conscientemente pelo labor intelectual, pela especula??o filos?fica do amor e pela paix?o de escrever. A leitura de sua obra representa um desafio ? sensibilidade do estudioso da literatura. Nesta disserta??o, tratamos desse trabalho em filigranas que a autora realiza. Situamo-nos nas obras Viagem e Mar absoluto como ?ncoras simb?licas de um discurso que nos remete ? rela??o do poetar com o pensar. Insere-se, assim, essa po?tica ceciliana num modo filos?fico plat?nico, trazendo elementos simb?licos, m?ticos, metaf?ricos capazes de remeter-nos ?s interpreta??es filos?ficas do s?c. XX, tal a heideggeriana que entende a poesia dentro do princ?pio do eterno jogo do ser, que ? o da pr?pria linguagem. Nossa preocupa??o fundamental foi trilhar os caminhos do erotismo filos?fico e a busca da autora em transcender a rigidez dos limites entre o masculino e o feminino, lan?ando-se num imagin?rio po?tico crist?o, reinterpretado neoplatonicamente. Exp?em-se Mulher e Letras ao espelho, velando e desvelando marcas e tra?os identit?rios. Tal jogo especular ofereceu-nos elementos po?ticos, est?ticos e uma experi?ncia ceciliana da linguagem do ser, des?gnio da poesia mesma. Deste nosso empreendimento, que ? tamb?m refletido e reflexivo, reunimos ?s Letras a Filosofia, ressaltando que ambas - de maneira diferente - nos deram acesso ? constru??o dessa poesia em que fulguram a escritura, o ser e a natureza metaforizada, caracterizando a multiplicidade de sentidos e a pluralidade de vozes do presente e do passado
27

Applications of Monolithic Capillary Electrochromatography (CEC): Method Development and Quantitation of Metabolites in Prostate Tissue and Insights into Chiral Recognition Mechanism

Lu, Yang 06 January 2017 (has links)
Capillary electrochromatography (CEC) is a major capillary electrophoresis (CE) mode that have been interfaced to mass spectrometry (MS) for sensitive and selective analysis of chiral compounds. This research expands CEC applications in cancer biomarker and chiral CE analysis. Chapter 1 is a review of liquid chromatography-mass spectrometry (LC/MS), gas chromatography-mass spectrometry (GC/MS), and capillary electrophoresis mass spectrometry (CE/MS) for analysis of metabolites in prostate cancer diagnostics and therapies. In this chapter, a literature survey was performed within the databases PubMed, 4 Caplus/Webline and Web of Sciences. A total 17 studies reporting on various analytical platforms for metabolite identification in prostate cancer research, which often include case-control comparison were identified and reviewed. Chapter 2 described the analysis of metabolite biomarkers in prostate cancer tissues by capillary electrochromatography mass spectrometry. In this chapter, a capillary CEC–MS/MS method was developed for the simultaneous determination and separation of eight proofs of concept (POC) metabolites (betaine, malate, proline, N-acetyl aspartate, N-acetylglucosamine, uracil, xanthine, and alanine) as potential prostate cancer diagnostic markers. A polymeric monolith column with a hydrophilic crosslinker and strong anion-exchange mixed-mode has been fabricated by an in situ copolymerization of vinyl benzyl trimethylammonium chloride, and bisphenol A glycerolate dimethacrylate (BisGMA) in the presence of methanol and dodecyl alcohol as porogens and AIBN as initiator. After CEC separation, samples were analyzed by a triple–quadrupole mass spectrometer operated in positive ion mode. After optimization, the data showed that the CEC-MS/MS method using monolithic column achieved a much better chromatographic selectivity compared to coated columns and increased sensitivity than bare fused silica column The effect of mobile phase pH, ACN percentage and additive were studies. Under the optimum mobile phase conditions, this method was carried out to separate and detect eight metabolites in the biopsy sample. The LOD for the metabolites is between 50nM-100nM. This method has successfully used to examine patients’ prostate cancer with an accuracy of 95%. Chapter 3 demonstrates Insights into Chiral Recognition Mechanisms in CEC using linear salvation energy relationship. By varying the linker (amide and carbamate), head group (alanine, leucine, and valine) and chain length (C8, C10 and C12) of the amino acid bound surfactants; monolithic column was made to ultimately understand the factors governing chiral stationary solid phase. Through the comparison of system parameters, we can see that surfactant head group, linker and chain length affect the separation of achiral and chiral compounds. Also, with the same type surfactant, data was presented to show how the trend of LSER parameters and how it affects separation between in CEC. This study showed the predictive capability of LSER to understand the aforementioned intermolecular processes controlling retention and by doing so, be able to quantitatively predict the experimental conditions to achieve an acceptable chiral separation.
28

An?lise filogen?tica de Gymnophiona M?ller, 1832 (Amphibia)

Souza, Camila Camargo de 30 March 2016 (has links)
Submitted by Caroline Xavier (caroline.xavier@pucrs.br) on 2017-11-09T17:46:02Z No. of bitstreams: 1 DIS_CAMILA_CAMARGO_DE_SOUZA_COMPLETO.pdf: 3948791 bytes, checksum: c827f34181e47b84d2dc6c25fa596df9 (MD5) / Approved for entry into archive by Caroline Xavier (caroline.xavier@pucrs.br) on 2017-11-09T17:46:13Z (GMT) No. of bitstreams: 1 DIS_CAMILA_CAMARGO_DE_SOUZA_COMPLETO.pdf: 3948791 bytes, checksum: c827f34181e47b84d2dc6c25fa596df9 (MD5) / Made available in DSpace on 2017-11-09T17:46:23Z (GMT). No. of bitstreams: 1 DIS_CAMILA_CAMARGO_DE_SOUZA_COMPLETO.pdf: 3948791 bytes, checksum: c827f34181e47b84d2dc6c25fa596df9 (MD5) Previous issue date: 2016-03-30 / Conselho Nacional de Pesquisa e Desenvolvimento Cient?fico e Tecnol?gico - CNPq / Gymnophiona M?ller, 1832?with 206 currently recognized species?is the least studied order within Amphibia. The phylogenetic relationships among its members have been historically unstable, with frequent taxonomic changes at the family level due to the recurrent presence of paraphyletic taxa. However, an increase of studies based on morphological and molecular data has built a scaffold of information about the evolutionary relationships among caecilians; even though, a phylogenetic classification of the order has remained a challenge. In 2011 a new taxonomy of Gymnophiona was proposed, where genera were arranged in nine families supposedly monophyletic. This taxonomy was not based on a phylogenetic analysis but on a consensus of the understanding of the evolutionary relationships of the group as inferred by previous studies. However, important conflicts exits among the results and type of analyses performed on these studies. Furthermore, only one study has included the known fossil taxon of Gymnophiona, which despite being fragmented is a valid source of evidence. Due to several and continuous efforts to generate data on caecilians, there is a wealth of hereditary characters available for phylogenetic studies. Thus, it has become crucial to perform a combined analysis of all these data (complete mitochondrial genomes, nuclear DNA sequences, phenotypic characters of extant and fossil taxa) to obtain a phylogenetic hypothesis that maximizes explanatory power. The objective of this study is to infer the evolutionary relationships of Gymnophiona based on a total evidence analysis using parsimony and dynamic homology to evaluate the current taxonomy of the group. Additionally, we also evaluate the effect of different types of alignment (tree versus similarity approaches), the influence of phenotypic characters on a dataset dominated by molecular characters, and the effect of coding indels as missing data. We compiled previously published phenotypic characters, DNA sequences available from GenBank of 47 nuclear and mitochondrial genes of all available taxa, and produced 42 new sequences. When comparing the results obtained from the tree-alignment analysis in POY with those of the similarity alignment in TNT, both recover Rhinatrematidae as sister of Ichthyophiidae + Teresomata. Within Rhinatrematidae, Epicrionops is paraphyletic in all analyses and the relationships within Ichthyophis are unsolved (a polytomy in the strict consensus). POY does not recovered Scolecomorphidae as the sister taxon of all other Teresomata but Typhlonectidae + Caeciliidae. Caecilia is paraphyletic with respect to Oscaecilia and Typhlonectes in relationship to Potamotyphlus. Scolecomorphidae is sister of Herpelidae + Chikilidae. The results of TNT recover a paraphyletic Herpelidae, with Herpele squalostoma sister of Chikilidae. Also, Siphonopidae is non-monophyletic. Indotyphlidae is non-monophyletic in both analyses and Idiocranium is consistently recovered as sister taxon of Dermophiidae. Dermophis is recovered as paraphyletic in the POY analysis, while both Dermophis and Gymnopis are paraphyletic in the TNT analysis. The strict consensus of the molecular dataset is highly congruous with that of the total evidence dataset; however, the former is better resolved (less polytomies), mainly within Indotyphlidae. The analysis of the phenotypic data alone resulted in a complete polytomy, illustrating the need of more research in this avenue. Coding indels as missing data did not cause important topological changes. The main conclusions derived from this study are: (i) the type of alignment of DNA sequences have an evident impact on the phylogenetic hypotheses of Gymnophiona; (ii) the apparent resolution on the evolutionary relationships of the extant supraspecific taxa of Gymnophiona and their monophyly presented in other studies are dependent on the exclusion of relevant evidence?taxa and characters?or the partial presentation of the optimal hypotheses; (iii) only a total evidence analysis allowed us to discover some of the potential cases of paraphyly or misidentification of vouchers; (iv) the phenotypic data currently used in the study of the evolutionary relationships of Gymnophiona contain important levels of non-congruent information and are not sufficient to place the fossil Eocaecilia micropodia within caecilians. This study reveals the need of detailed revision of the taxonomy and phylogeny of Gymnophiona. / Gymnophiona M?ller, 1832 ? a ordem menos estudada dentro de Amphibia, com 206 esp?cies conhecidas. As rela??es filogen?ticas do grupo permaneceram inst?veis por muito tempo, sofrendo com mudan?as no n?mero de fam?lias, devido ? constante presen?a de t?xons parafil?ticos. Uma crescente de estudos com produ??o de evid?ncias moleculares e morfol?gicas tem formado um arcabou?o de informa??es sobre as rela??es evolutivas do grupo. Mesmo assim, uma classifica??o filogen?tica de toda a ordem n?o representava uma tarefa f?cil. Em 2011, foi proposta uma classifica??o ao n?vel de fam?lia, onde os g?neros foram distribu?dos em nove fam?lias supostamente monofil?ticas. Essa proposta n?o foi baseada em uma an?lise filogen?tica, mas sim em um consenso do entendimento das rela??es filogen?ticas inferidas em estudos pr?vios, sendo muitos deles discordantes, tanto em tipos de an?lises, quanto em resultados. Apenas um estudo incluiu um t?xon f?ssil, que apesar de ser pouco representativo em quantidade, representa uma fonte v?lida de evid?ncia. Devido ao grande esfor?o para gerar dados e obter informa??es acerca dos Gymnophiona, existem in?meros caracteres heredit?rios dispon?veis. Dessa forma, percebe-se uma import?ncia em unir todos esses dados (genomas mitocondriais completos, sequ?ncias de genes nucleares, caracteres fenot?picos dos t?xons viventes e f?ssil) para compor uma nova proposta filogen?tica com o maior poder explicativo. Assim, o objetivo principal deste estudo foi inferir as rela??es evolutivas da ordem Gymnophiona em um contexto de evid?ncia total, sob an?lises de parcim?nia e homologia din?mica e avaliar a taxonomia atual de Gymnophiona com base na(s) ?rvore(s) mais parcimoniosa(s). Adicionalmente, avaliar o efeito de diferentes tipos de alinhamento, a influ?ncia de caracteres fenot?picos em um dataset dominado por dados gen?ticos e o efeito de codificar os indels como dados faltantes. Para isso foram compilados caracteres morfol?gicos de estudos pr?vios, sequ?ncias dispon?veis no GenBank, referentes a 47 genes (nucleares e mitocondriais) de todas as esp?cies dispon?veis, al?m da produ??o de 42 novas sequ?ncias. Comparando os resultados gerados a partir do alinhamento por ?rvore (POY) e do alinhamento por similaridade (TNT) encontramos Rhinatrematidae como grupo-irm?o de Ichthyophiidae + Teresomata. Dentro de Rhinatrematidae, Epicrionops foi recuperado parafil?tico em todas as an?lises e as rela??es dentro de Ichthyophiidae s?o uma politomia. A an?lise do POY n?o recupera Scolecomorphidae como t?xon-irm?o dos demais Teresomata, e sim Typhlonectidae + Caeciliidae. Caecilia ? parafil?tica a Oscaecilia, assim como Typhlonectes com rela??o a Potamotyphlus. Na an?lise via TNT, Herpelidae foi recuperada parafil?tica, com Herpele squalostoma agrupado com Chikilidae. Na an?lise do TNT, Siphonopidae n?o foi recuperada monofil?tica. A fam?lia Indotyphlidae foi n?o-monofil?tica em ambas as an?lises e Idiocranium foi recuperado como o t?xon-irm?o de Dermophiidae. Dermophis surge parafil?tico na an?lise do POY, enquanto que pelo TNT tanto Dermophis quanto Gymnopis surgen parafil?ticos. A topologia da ?rvore constru?da apenas com sequ?ncias de DNA, mostrou-se altamente semelhante ao consenso gerado pelo TNT, embora com alguns poucos clados melhor resolvidos, principalmente em Indotyphlidae. J? a an?lise unicamente morfol?gica restringiu-se a uma politomia total, o que pode ser justificado pela falta de caracteres morfol?gicos ?teis, e que tamb?m pode ser um reflexo da falta de conhecimento acerca deste tipo de evid?ncia. Quanto ? codifica??o de indels como quinto estado ou como dados faltantes, n?o foi observada vantagem sobre nenhum dos testes em rela??o ? topologia do consenso estrito. As principais conclus?es derivadas dos resultados obtidos s?o: (i) o tipo de alinhamento das sequ?ncias de DNA tem um impacto evidente nas hip?teses filogen?ticas; (ii) a aparente resolu??o da hist?ria evolutiva dos atuais t?xons supraespec?ficos de Gymnophiona e sua monofilia, apresentada em outros estudos, dependem da exclus?o de evid?ncia relevante das an?lises ou da apresenta??o parcial das hip?teses ?timas; (iii) s? a an?lise de evid?ncia total permitiu descobrir casos potenciais de parafilia ou identifica??o errada de terminais; (iv) os dados fenot?picos atualmente usados no estudo das rela??es evolutivas de Gymnophiona t?m altos n?veis de informa??o n?o congruente e n?o s?o suficentes para a inclus?o do t?xon f?ssil Eocaecilia micropodia dentro de Gymnophiona. O presente estudo revela a necessidade de uma revis?o detalhada da taxonomia e filogen?tica de Gymnophiona.
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Étude des effets d'irradiation dans les montmorillonites. Application au stockage des déchets radioactifs.

Sorieul, Stéphanie 24 November 2003 (has links) (PDF)
Les smectites sont des matériaux envisagés pour le stockage des déchets radioactifs en tant que barrière ouvragée et encaissant géologique en raison de leurs propriétés physiques et chimiques particulières. Dans ce contexte, il est important de connaître leur comportement sous irradiations afin de pouvoir estimer la sûreté et la durabilité de l'ouvrage de stockage. Pour cette étude, deux montmorillonites ont été choisies. L'une des argiles provient de la province de Liaoning, en Chine (CHI) et présente la particularité de contenir des défauts d'irradiation stables. La seconde smectite (notée MX) a été extraite de la bentonite de référence méthodologique MX-80 et purifiée à l'aide de différentes techniques chimiques. La spectroscopie par Résonance Paramagnétique Électronique (RPE) a permis d'identifier plusieurs défauts d'irradiations qui se différencient par leur stabilité thermique et leurs caractéristiques RPE. Tous ces défauts peuvent être décrit comme des trous localisés sur une orbitale d'un oxygène lié à un silicium dans le feuillet argileux. Leur concentration augmente avec la dose jusqu'à atteindre une valeur de saturation, mais des différences sont observées entre les deux échantillons. La production de défauts ponctuels est également sensible au type de rayonnements et à la composition de l'espace interfoliaire (nature du cation compensateur, quantité d'eau interfoliaire). L'utilisation conjuguée de la RPE et de la spectroscopie Mössbauer a permis de mettre en évidence deux effets d'irradiation sur le fer structural. La montmorillonite MX purifiée est oxydée alors que la montmorillonite de Chine et la montmorillonite MX non déferrifiée sont réduites. Les irradiations modifient également l'environnement du fer structural. L'intensité du changement d'état d'oxydation dépend du type de rayonnement et de la nature du cation interfoliaire. En revanche, l'influence de l'eau interfoliaire semble être secondaire. Enfin, une variation de la Capacité d'Échange Cationique en fonction de la teneur en fer trivalent a été enregistrée. L'amorphisation de la montmorillonite MX a également été étudiée en fonction de la température. Elle dépend du rayonnement et de la nature du cation interfoliaire. Une dépendance de la dose maximale d'amorphisation en fonction de la masse du cation a été mise en évidence pour l'irradiation avec des ions Krypton.
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Column Development in Capillary Electrophoresis and Electrochromatography for Bioanalytical Applications

Johannesson, Nina January 2006 (has links)
Analysis of biological samples can be a difficult task. This thesis covers a broad aspect of the analytical areas of capillary electrophoresis (CE) and capillary electrochromatography (CEC) in combination with mass spectrometry (MS) that are of great importance for achieving fast, accurate and sensitive bioanalyses. A significantly time reduced and automated system for sample cleanup was developed to greatly simplify the pretreatment process of biological samples with a complex matrix. Desalting and preconcentration of species in urine was conducted and the limit of detection for the antidepressant escitalopram was lowered 10 times. This extraction devise was also successfully incorporated in a chip based platform for the possibility to be a part of multidimensional separation systems. The reduced risk of sample loss leads to improved detection limits, which are usually one the most challenging parts when working with bioanalyses. In the area of separation, a monomer surface with tailored hydrophobicity was developed to achieve rapid, high efficient separations of complex mixtures. Within five minutes a tryptic digest of a protein could be separated and then identified by a Mascot search. The applications addressed have been focused on medical conditions which are of highest interest for both physicians and patients. A high throughput analysis of the kynurenine metabolites with CE-MS offers a new method to rapidly examine samples from patients with neurological disorders. A screening study of possible biomarkers for the two different types of appendicitis, gangraenous and phlegmonous was conducted. Indicative patterns were found for both pre and post surgery of the two types of inflammation as well as between them. The divergences were traced back to the MS peaks obtained in the CE- and CEC-MS setups as possible biomarkers for the two forms of appendicitis. A preliminary study of polycystic ovary syndrome also offered some valuable results for future biomarker identification.

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