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Lecroq, William. "Etude de la formation de radicaux phosphorés et leurs applications en synthèse organique." Thesis, Normandie, 2019. http://www.theses.fr/2019NORMC265.
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Les travaux présentés dans ce manuscrit de thèse traitent de l’étude et de l’utilisation des radicaux phosphorés en synthèse organique.Le développement d’une méthode de synthèse des dérivés arylphosphonates photo induite associant simplement les sels de diaryliodonium en présence de phosphite dans l’acétonitrile a été discuté. Des études mécanistiques nous ont permis de proposer un mecanisme de cette méthode photo induite, passant par un complexe à transfert de charge.La réactivité des radicaux phosphoranyle a été utilisée pour l’étude de la désoxygénation des amines N-oxyde, utilisant un organocatalyseur phosphoré capable d’être réduit par le phénylsilane. Des études théoriques ont permis de montrer que l’espèce photo active est la pyridine N-oxyde, évolue pour générer un intermédiaire oxaziridine. L’utilisation du phénylsilane pour la réduction des amines tertiaires N-oxyde à température ambiante et sans irradiation lumineuse a été envisagée, nous permettant de développer une méthode de désoxygénation sélective de dérivés hétérocycles-amines tertiaires N,N-dioxydeThis manuscript explores the reactivity of phosphorous radicals in organic chemistry.The development of a photo induced method for the synthesis of arylphosphonate derivatives by simply combining diaryliodonium salts with phosphites in acetonitrile is discussed. Mechanistic studies of this photo-induced process allowed us to propose a mechanistic pathway of the reaction, where a charge transfer complex is a key intermediate in the reaction.The reactivity of the phosphoranyl radicals was used for the study of the deoxygenation of amine N-oxydes, using an organophosphorous catalyst, which can be reduced by phenylsilane. Theoretical studies showed that the photo active species is the pyridine N-oxide, rearrange to form an oxaziridine. The utilization of phenylsilane for the deoxygenation of tertiary amine N-oxide at room temperature without visible light irradiation was discussed, allowing the discovery of a selective deoxygenation method for N,N-dioxides
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Zinina-Izri, Irina Victorovna. "Copolymérisation sous irradiation UV des couples du type accepteur/donneur sans photoamorceur. Rôle du complexe à transfert de charge (CTC)." Montpellier 2, 1998. http://www.theses.fr/1998MON20076.
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Notre travail presente une etude de quelque couples du type accepteur / donneur qui englobe : - la caracterisation des systemes par plusieurs techniques d'analyse telles que la calorimetrie differentielle a balayage (dsc), la spectroscopie ir, la rmn, la spectroscopie uv en temps reel ; - de la copolymerisation photoinduite des systemes du type accepteur / donneur sans photoamorceur par la photocalorimetrie a compensation de puissance (dpc), la spectroscopie ir en temps reel et la rpe qui permettent de suivre le processus ; - la caracterisation du materiau obtenu complete le travail.
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Coimbra, Daniel Fernando. "Natureza da ligação Ru-NO em novos nitrosilo complexos de rutênio com ligantes quelantes CCC e CNC contendo carbenos." reponame:Repositório Institucional da UFSC, 2015. https://repositorio.ufsc.br/xmlui/handle/123456789/136460.
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Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro de Ciências Físicas e Matemáticas, Programa de Pós-Graduação em Química, Florianópolis, 2015.Made available in DSpace on 2015-11-17T03:05:39Z (GMT). No. of bitstreams: 1 335949.pdf: 3299080 bytes, checksum: fc7c42f7c1c0103a1f2daa1e2f7d6199 (MD5) Previous issue date: 2015
Compostos capazes de liberar ou sequestrar óxido nítrico são promissores agentes terapêuticos como antimicrobianos, reguladores da pressão sanguínea, no combate ao câncer, dentre outros. Neste trabalho foram investigados novos nitrosilo complexos de rutênio, potencialmente liberadores de óxido nítrico, contendo ligantes pinça quelantes tridentados em que dois sítios coordenantes são carbenos N heterociclos ligados por uma ponte fenila ou piridil que também coordena-se ao centro metálico. Derivados destes complexos são obtidos pela substituição de grupos alquila no átomo de nitrogênio dos grupos imidazolilideno. A estrutura geométrica e eletrônica destes complexos organometálicos e de seus produtos de redução monoeletrônica foram investigadas por métodos computacionais empregando-se a Teoria do Funcional da Densidade (DFT). A natureza da ligação química Ru NO foi estudada utilizando-se as técnicas de Análise de Decomposição de Energia de Su-Li (Su-Li EDA) e Orbitais Naturais de Ligação (NBO). Neste trabalho também foi avaliada uma metodologia para a predição de potenciais de redução dos nitrosilo complexos de rutênio estudados.
Abstract : Compounds capable of releasing or scavenging nitric oxide are promising therapeutic agents as antimicrobials, blood pressure regulators, in cancer treatment and many others. In this work were investigated new ruthenium nitrosyl complexes, potentially capable of releasing nitric oxide, containing chelating tridentade pincer ligands in which two coordinating sites are N-heterocyclic carbenes united by a bridging coordinating phenyl or pyridyl unit. Derivatives of these complexes are obtained by substitution of alkyl groups at the imidazolylidene nitrogen. The geometric and electronic structure of these organometallic complexes and their one-electron reduction products were investigated by computational methods employing Density Functional Theory. The nature of the Ru NO chemical bond was investigated using the Energy Decomposition Analysis of Su-Li and Natural Bond Orbitals. In this work it was also evaluated a methodology for the prediction of reduction potentials of the ruthenium nitrosyl complexes under investigation.
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Benbahouche, Nour el Houda. "Investigating the role of extended CBC complexes in RNA metabolism." Thesis, Montpellier, 2015. http://www.theses.fr/2015MONTS002.
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Le CBC intervient dans de nombreuses étapes du métabolisme des ARN, telle que l’épissage, la maturation de l’extrémité 3’, la dégradation, l’export et la traduction. Ainsi, le CBC constitue un complexe majeur qui peut orchestrer les différentes étapes de maturation des ARN. Récemment, nous avons identifié le complexe CBCAP, composé de CBC, ARS2 et PHAX. Nous avons montré que la protéine ARS2 stimule la formation des extrémités 3’ de plusieurs familles d’ARN dont les snARN. De plus, ARS2 stimule le recrutement de PHAX sur le CBC. Ainsi, nous proposons un modèle où CBC-ARS2 stimule la formation de l’extrémité 3’ des pré-snARN et recrute PHAX pour favoriser leur export. Une autre étude a identifié un autre complexe le CBCN, constitué de CBC, Ars2, et de ZC3H18-NEXT au lieu de PHAX. CBCN recrute l’exosome et stimule la dégradation de certains ARN, comme les PROMPTS et les transcrits «read-through » des snARN et des ARNm d’histone. Ainsi, PHAX et ZC3H18 destinent leur ARN cibles vers l’export ou la dégradation. Il a été montré que PHAX reconnait et lie spécialement les ARN de petite taille. D’une manière remarquable, nos données de CLIP-Seq et de RIP suivie par des analyses avec des puces « All genes » montrent que PHAX lie aussi d’autres familles d’ARN. En effet, PHAX lie les ARNm ainsi que des ARN non-codant avec une légère préférence pour les snARN (en comparaison avec ZC3H18). Afin de mieux comprendre le rôle de PHAX et ZC3H18, j’ai tout d’abord démontré si les deux protéines se lient simultanément au CBC. Pour ce faire, J’ai réalisé des tests de compétitions entre PHAX et ZC3H18, in vivo, et j’ai montré que la surexpression de ZC3H18 déplace PHAX du CBC et vice versa. Puis en utilisant la technique de « Tethering Assays » j’ai pu montrer que PHAX et ZC3H18 ont des effets opposés sur la biogénèse des ARNm. De plus PHAX semble avoir un effet positif sur la maturation des ARNm et ce, en empêchant ZC3H18 et l’exosome d’être recruter. Nous avons aussi montré que la déplétion de PHAX et ZC3H18 a des conséquences fonctionnelles sur le taux des formes matures des snARN. Dans le but de caractériser la protéine ZC3H18, j’ai réalisé un crible double-hybride et j’ai montré que ZC3H18 interagit avec plusieurs facteurs d’épissage. J’ai aussi identifié les domaines de ZC3H18 impliqués dans ses différentes interactions. D’une manière intéressante, l’interaction de ZC3H18 avec certains facteurs d’épissage peut être exclusive à son interaction avec NEXT. De plus, des expériences de protéomique réalisés sur un des facteurs d’épissage trouvé dans le crible, montrent qu’il co-purifie au sein d’un complexe qui pourrait faire le lien entre la coiffe et la machinerie d’épissage. En accord avec ces résultats, nos données de RNA-seq montrent que la déplétion de ZC3H18 engendre un défaut d’épissage pour des introns qui sont proches de la coiffe et ceci pour un nombre restreint de gènes. Ainsi, notre travail décode davantage le rôle de la coiffe dans les différentes étapes de maturation des ARN et suggère un modèle où la séquence des transcrits naissant stimule la formation d’un complexe spécifique à cet ARN parmi plusieurs autresThe cap binding complex (CBC) plays a key role in a number of gene expression pathways and has been proposed to participate in the discrimination of RNA families. It also enhances many RNA processing steps, including transcription, splicing, 3’end formation, degradation, export and translation.Recently, we identified the CBCAP complex, composed of CBC, Ars2 and PHAX. We showed that Ars2 stimulates snRNA 3'-end processing as well as PHAX binding to the CBC, hence coupling snRNA maturation with their export. Other studies showed that the CBC and ARS2 can form another complex that contains ZC3H18-NEXT instead of PHAX. This complex, named CBCN, is a cofactor of the RNA exosome and is involved in the degradation of cryptic RNAs such as PROMPTs and read-through transcripts at histone and snRNA genes. Thus, PHAX and ZC3H18 target specific families of capped RNA toward either export or degradation. Previous studies proposed that PHAX binds specifically to small RNAs and discriminates them over other RNA species. Surprisingly, our CLIP-Seq and RIP-microarrays data showed that in contrast to expectations, PHAX was not specific for snRNAs. It also binds mRNAs as well as other non-coding RNAs and has a weak preference for snRNAs comparing to ZC3H18. To better understand the role of PHAX and ZC3H18, Ifirst determined whether PHAX and ZC3H18 can bind simultaneously to the CBC. Competitive LUMIER IPs indicated that binding of these proteins is mutually exclusive. I then used tethering assays and could show that PHAX and ZC3H18 have opposite effect on mRNA biogenesis. These data go against a model where binding of PHAX or ZC3H18 discriminate RNA families, and instead suggest promiscuous binding for these proteins. In addition, PHAX may exert a positive effect on mRNA processing by preventing binding of ZC3H18 and recruitment of the RNA exosome. Last but not least, our RT-QPCR data show that PHAX and ZC3H18 depletions have functional consequences on the level of mature snRNA, and this is due to a competition between both proteins which occur on those snRNA read-through transcripts.To further explore the role of ZC3H18, I performed a two-hybrid screen and identified several splicing factors. I could validate these interactions, identify the domains involved and show that binding of some of these factors is exclusive with that of NEXT. Importantly, proteomic experiments with one of these factors identified a complex that makes the link between the cap and the splicing machinery. In agreement, RNA-Seq analysis of ZC3H18 knock-down cells showed alterations in splicing of cap-proximal introns, for a small set of genes.Altogether, this work reveals how the multiple roles of the RNA cap are achieved at the biochemical level, and suggests that the nascent RNA sequence triggers formation of one among several mutually exclusive complexes
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Bances, Ricardo M., and Norberto J. Chau. "CMC Complejos de cadenas de R-módulos." Pontificia Universidad Católica del Perú, 2012. http://repositorio.pucp.edu.pe/index/handle/123456789/95810.
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Tensmeyer, Nicole C. "The Role of the Chaperone CCT in Assembling Cell Signaling Complexes." BYU ScholarsArchive, 2020. https://scholarsarchive.byu.edu/etd/9192.
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In order to function, proteins must be folded into their native shape. While this can sometimes occur spontaneously, the process can be hindered by thermodynamic barriers, trapped intermediates, and aggregation prone hydrophobic interactions. Molecular chaperones are proteins that help client proteins or substrates overcome these barriers so that they can be folded properly. One such chaperone is the chaperonin CCT, a large MDa protein made up of 16 paralogous subunits that form a double ring structure. CCT encapsulates its substrates in a central cavity, where they are sequestered and folded, using ATP binding and hydrolysis to drive conformational changes in the CCT-substrate complex. CCT mediates the folding of many substrates involved in a variety of cellular process, including the cytoskeletal proteins actin and tubulin, and the G protein subunit Gabg, which signals downstream of GPCRs in a variety of cellular processes. We showed that CCT is responsible for folding the b-propeller containing proteins, mLST8 and Raptor, which are subunits of the mTOR complexes. The mTOR complexes (mTORC1 and mTORC2) are master regulators of cell growth and survival by controlling processes such as protein synthesis, energy metabolism, cell survival pathways and autophagy. CCT folds mLST8 and Raptor and help them assemble into the mTOR complexes. As a result, CCT is required for functional mTOR signaling. Furthermore, we solved a 4.0 Ǻ resolution structure of mLST8 bound to CCT. Surprisingly, mLST8 is found in the center of the folding cavity, in between the rings, despite previous evidence suggesting that substrates bind only in the apical domains. Given its role in folding and assembling the mTOR complexes, G proteins, and many other proteins involved in cell survival pathways, CCT has been implicated in cancer. CCT upregulation often correlates with a worse prognosis, likely because uncontrolled growth requires increased chaperone capacity. The peptide CT20P has been shown to have cytotoxic effects in cancer cells, likely through its binding to CCT. We characterized CT20P, showing that it binds to CCT and inhibits its substrate-folding functions in cells. We specifically showed that a GFP-CT20P fusion protein inhibited the assembly of two important signaling complexes Gbg and mTORC1. These results show that CT20P is a useful inhibitor for the study of CCT function.
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Aoba, Takuma. "Structural Analysis of Cell Signaling Complexes." BYU ScholarsArchive, 2016. https://scholarsarchive.byu.edu/etd/6583.
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Bardet-Biedl syndrome (BBS) is a rare genetic disease that causes retinal degradation, obesity, kidney dysfunction, polydactyly, and other cilium-related disorders. To date, more than 20 BBS genes, whose mutants cause BBS phenotypes, have been identified, and eight of those (BBS1-2, 4-5, 7-9, and 18) are known to form the BBSome complex. Recent studies have revealed that the BBSome is closely involved in the trafficking of signaling proteins in the primary cilium. Mutations in BBS genes are highly pathogenic because trafficking in the primary cilium is not fully functional when BBS mutations impair assembly of the BBSome. However, the functional links between onset of BBS and BBSome assembly are not well understood. To address this gap in knowledge, we examined the structure of a BBSome assembly intermediate, the BBSome core complex (BBS2, 7, and 9). We employed a combination of chemical crosslinking coupled with mass spectrometry (XL-MS) and electron microscopy (EM) to determine the structure. We applied this structural information to BBS mutations in the core complex to understand how these mutations might cause the disease. These results provide the first structural model of the BBSome core complex and give insight into the molecular basis of Bardet-Biedl syndrome. We have also investigated the mechanism of assembly of the two mTOR kinase complexes (mTORC1 and 2). mTOR is a master regulator of cell metabolism, growth and proliferation. As such, mTOR is a high-value drug target. We investigated the mechanism of assembly of these mTOR complexes and found that the cytosolic chaperonin CCT contributes to mTOR signaling by assisting in the folding of mLST8 and Raptor, components of mTORC1 and mTORC2. To understand the function of CCT in mTOR complex assembly at the molecular level, we have isolated the mLST8-CCT complex and performed a structural analysis using chemical cross-linking couple with mass spectrometry (XL-MS) and cryogenic EM. We found that mLST8 binds CCT deep in its folding cavity, making specific contacts with the CCTα and γ subunits and forming a near-native β-propeller conformation. This information can be used to develop new therapeutics that regulate mTOR activity by controlling mTOR complex assembly.
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Liu, Lei [Verfasser], and Dieter [Akademischer Betreuer] Heermann. "Multiscale Modelling of CTCF and its Complexes / Lei Liu ; Betreuer: Dieter Heermann." Heidelberg : Universitätsbibliothek Heidelberg, 2015. http://d-nb.info/1180394976/34.
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Thiemann, Stefan [Verfasser]. "Functional characterization of ClC-K/barttin complexes of different stoichiometries / Stefan Thiemann." Hannover : Gottfried Wilhelm Leibniz Universität, 2021. http://d-nb.info/1238222625/34.
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Schulze, Wiebke Manuela [Verfasser], and Stephen [Akademischer Betreuer] Cusack. "Mutually Exclusive CBC and CBC-ARS2 Containing Complexes Coordinate the Fate of RNA Polymerase II Transcripts / Wiebke Manuela Schulze ; Betreuer: Stephen Cusack." Heidelberg : Universitätsbibliothek Heidelberg, 2017. http://d-nb.info/1177251558/34.
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Dhavale, Madhura Vinayak. "Role of Molecular Chaperonin CCT and Its Co-Chaperone PhLP1 in the Assembly of mTOR Complexes." BYU ScholarsArchive, 2017. https://scholarsarchive.byu.edu/etd/6942.
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mTOR is the central kinase in biochemical pathways that regulate cellular growth, protein synthesis and cell survival. Deregulation of mTOR signaling results in uncontrolled cell proliferation and hence is implicated in various cancers and autoimmune diseases. mTOR functions through two distinct signaling complexes, called mTORC1 and mTORC2. CCT is a cytosolic chaperonin that assists in folding of several protein substrates. In these studies, we have identified two components of the mTOR complexes, mLST8 and Raptor, as substrates of CCT. We have performed biochemical and signaling studies which indicate that CCT is involved in assembly and signaling of mTOR complexes by folding β-propeller domains of mLST8 and Raptor. We have also obtained high resolution structural information of the mLST8-CCT complex by cryo-EM and mass spectrometric cross-linking. Moreover, we have explored the role of PhLP1 as a co-chaperone for CCT in the assembly of mTOR complexes. Interestingly, we found that PhLP1 plays very different roles in the case of mLST8 and Raptor. While PhLP1 participate in assembly of mLST8 into mTOR complexes, it facilitates degradation of Raptor. These biochemical data, combined with structural information, can be used to design small molecules that modulate mTOR signaling by affecting the formation of intact mTOR complexes.
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Breitling, Frank Michael. "Boron-bridged constrained geometry complexes and related compounds." Thesis, Imperial College London, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.420881.
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Bezerra, Kelton Silva. "Um teorema de rigidez para hipersuperfÃcies cmc completas em variedades de Lorentz." Universidade Federal do CearÃ, 2009. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=4823.
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O objetivo deste trabalho à apresentar um teorema de classificaÃÃo para hipersuperfÃcies completas e de curvatura mÃdia constante em variedades de Lorentz de curvatura seccional constante, sob certas limitaÃÃes da curvatura escalar. Para isto usaremos a fÃrmula de Simons, que nos dà uma relaÃÃo entre as transformaÃÃes de Newton Pr e o laplaciano da norma ao quadrado do operador de Weingarten Ã, e um princÃpio do mÃximo devido H. Omori e S. T. Yau. Como primeira aplicaÃÃo obtemos uma classificaÃÃo das hipersuperfÃcies tipo-espaÃo completas e de curvatura mÃdia constante no espaÃo de De Sitter, com curvatura escalar R maior ou igual a 1. ConcluÃmos tambÃm que toda hipersuperfÃcie tipo-espaÃo completa e de curvatura mÃdia constante positiva do espaÃo de Lorentz-Minkowski, com curvatura escalar nÃo-negativa, à um cilindro sobre uma curva plana e, a menos de isometrias, determinamos tal curva.Our aim in this work is to show a classification theorem for complete CMC hipersurfaces in Lorentz manifolds of constant sectional curvature, under certains bounds on the scalar curvature. To this end we use Simons formula, wich gives a relation between Newton transformations and the Laplacian of the squared norm of the Weingarten operator A, as well as a maximum principle due to H. Omori and S. T. Yau. We obtain, as a first application, a classification of complete spacelike CMC hypersurfaces of the De Sitter space, having scalar curvature R maior ou igual a 1. We also conclude that all complete spacelike hypersurfaces with positive constant mean curvature and nonegative scalar curvature in the Lorentz-Minkowski space are cylinders over a plane curve and, up to isometries, we determine this curve.
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Ruppert, Jan Gustav. "Functional analysis of heterochromatin protein 1-driven localisation and activity of the chromosomal passenger complex." Thesis, University of Edinburgh, 2018. http://hdl.handle.net/1842/33158.
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The ultimate goal of mitosis is the equal distribution of chromosomes between the two daughter cells. One of the key players that ensures faithful chromosome segregation is the chromosomal passenger complex (CPC). CPC localisation to mitotic centromeres is complex, involving interactions with Shugoshin and binding to phosphorylated histone H3T3. It was recently reported that Heterochromatin Protein 1 (HP1) has a positive impact on CPC function during mitosis. The interaction between HP1 and the CPC appears to be perturbed in cancer-‐derived cell lines, resulting in decreased HP1 levels at mitotic centromeres and may be a potential cause for increased chromosome mis-‐segregation rates. In this study, I tethered HP1α to centromeres via the DNA-‐binding domain CENP-‐B. However, instead of improving the rate of chromosome mis-‐segregation, HP1α tethering resulted in activity of the spindle assembly checkpoint and destabilisation of kinetochore-‐microtubule attachments, most likely caused by the robust recruitment of the CPC. Tethered HP1α even traps the CPC at centromeres during mitotic exit, resulting in a catalytically active CPC throughout interphase. However, it was not clear whether endogenous HP1 contributes to CPC localisation and function prior to mitosis. Here I also describe a substantial interaction between endogenous HP1 and the CPC during the G2 stage of the cell cycle. The two isoforms HP1α and HP1γ contribute to the clustering of the CPC into active foci in G2 cells, a process that is independent of CDK1 kinase activity. Furthermore, the H3S10ph focus formation in the G2 phase appears to be independent of H3T3ph and H2AT120ph, the two histone marks that determine the CPC localisation in early mitosis. Together, my results indicate that HP1 contributes to CPC concentration and activation at pericentromeric heterochromatin in G2. This novel mode of CPC localisation occurs before the Aurora B-‐driven methyl/phos switch releases HP1 from chromatin, which possibly enables the H3T3ph and H2AT120ph driven localisation of the CPC during mitosis.
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Barp, Denise Rippel Araújo. "Design e materiais : contribuição ao estudo do processo de corte de ágata por jato d'água em formas complexas." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2009. http://hdl.handle.net/10183/18983.
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No estado do Rio Grande do Sul, estão localizadas importantes regiões de extração e processamento do material gemológico ágata. No Distrito Mineiro do Salto do Jacuí encontram-se as maiores jazidas de ágata do Brasil e do Mundo. No município de Soledade se concentram as principais empresas de beneficiamento e comércio de materiais gemológicos. Apesar da abundância de material, a maioria dos objetos produzidos apresenta baixo grau de inovação, os produtos oferecidos no mercado são muito semelhantes entre si e tem, em comum, a falta de diferencial e de utilização de processos que envolvam tecnologia. A ágata é geralmente exportada em estado bruto ou apresentando baixo grau de aproveitamento. O processamento mais comum, utilizado na maior parte das empresas, é o corte em chapas que posteriormente são lixadas, polidas e tingidas em diversas cores. Entre as empresas pesquisadas no presente estudo apenas uma já utiliza processos envolvendo novas tecnologias. Pode-se afirmar que a pesquisa e estudos que auxiliem em um melhor aproveitamento do material ágata possam representar novas oportunidades de produção de objetos e adornos pessoais (jóias) modificando um cenário onde o design inovador é pouco explorado e apresentado. A metodologia empregada para a realização deste estudo contemplou etapas de conhecimento da realidade dos locais de extração, beneficiamento e comercialização de ágata, avaliação dos processos, ensaio de usinagem convencional CNC, ensaios de usinagem não convencional por jato d’água CNC e desenvolvimento de produtos em formas complexas. Foram realizados vinte e quatro ensaios de usinagem, a análise posterior identifica larguras e espessuras ideais buscando a otimização da matéria-prima. Desta forma foi possível alcançar o objetivo principal nesta pesquisa de realizar o corte de ágata com utilização de tecnologia CNC em peças com formas complexas.Rio Grande do Sul State, Brazil, has important regions of extraction and processing of agate. Salto Jacuí Mining District, in the central region of this State, is one of the largest and more importante agate’s mines region of Brazil and even of the World. In Soledade town, there are the most important gemstone processing and trade companies of this State. Despite the abundance of gem materials, most of the objects produced in the different companies are very similar and have in common that they seldom are manufactured using new technological processes. Agate is usually exported as raw material or as cut polished slabs which can be dyed in various colors. Among several companies studied in this research, only one uses industrial processes involving new technologies. So, scientifical studies to indicate a better use of agate produced in Rio Grande do Sul, can provide new opportunities for the production of objects and personal ornaments (jewelry), modifying the trade where innovative designs are little explored. The methodology used in this study had several steps: identification of the extraction, processing and trade places of agate; evaluation of the industrial benefit processes used in agate; testing of conventional CNC machining on agate slabs; and testing on agate slabs of non-conventional computer controled machining by water jet cutting (WJC), with development of complex forms agate products. Twenty-four machining tests were carried out, with further analysis identifying ideal widths and thicknesses to optimize the use of agate raw material. With these tests, it was possible to achieve the goal of this study, which is to cut agate using water jet technology, in order to produce agate objects with complex forms.
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Kandaskalov, Dmytro. "Etude théorique de défauts ponctuels et complexes dans les métaux : application au fer-cc et nickel-cfc." Thesis, Toulouse, INPT, 2013. http://www.theses.fr/2013INPT0007/document.
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L’étude des défauts ponctuels (lacunes, impuretés) et des complexes (cavités, joints de grains, etc.) est un domaine important de la physique du solide. Les propriétés physiques et chimiques des matériaux (élasticité, plasticité, fragilité, etc.) sont très souvent corrélées à la présence de ces défauts. Les techniques expérimentales ne sont cependant pas toujours en mesure de fournir une compréhension suffisante de ceux-ci. Dans ce cas-là, les simulations numériques et la modélisation à l’échelle atomique sont des outils utiles pour interpréter les résultats expérimentaux. Mon travail de thèse se situe dans ce cadre. Le manuscrit comporte 4 principales parties. Dans la première et la deuxième partie, nous présentons les principes de la DFT et la méthodologie utilisée dans cette thèse. La troisième partie de ce manuscrit résume l’étude théorique par DFT de la formation, la migration et la diffusion de différentes configurations de multi-lacunes Vn(n=1-15) dans le fer cubique centré. Les configurations de Vn les plus stables y sont décrites en détail : les énergies de formation, de liaison et de piégeage. La migration de différentes multilacunes est discutée en détail d’un point de vue énergétique et configurationnelle. Dans la dernière partie, nous nous intéressons à l’absorption du soufre dans différents sites (interstitiel et substitutionnel) du massif de Ni et sa ségrégation vers les surfaces Ni (100) et Ni (111). L’étude du soufre en volume permet de clarifie sa position en solution solide. Nous discutons des interactions soufre-soufre et avec le métal de base. La ségrégation et l’absorption sur des surfaces libres du nickel est aussi abordée en détailThe study of point defects (vacancies, impurity) and complex defects (cavities, grain boundary etc.) is a major challenge for solid state physics. The physical and chemical properties of materials (such elasticity, plasticity, embrittlement etc.) are correlated to the presence of these defects. The experimental study is not always able to bring sufficient information about them. In this way computational simulations and the modeling on the atomic level is efficient to interpret the experimental results and to obtain new informations. This PhD work consists also in a theoretical study of defects in metals. This manuscript is organized in four main parts. In the first and second part, we present the theoretical principles and the methodology used in this work. In the third part, we report a long discussion on the study of formation, migration and diffusion of multivacancies Vn in the bcc-iron system. The main objective of this study is to identify and to analyze most stable configurations of multivacancies for different sizes of Vn (n=1-15) in Fe. The migration is also investigated. In the last part, we present a study of S atoms in nickel. The different sites (interstitial and substitutional sites) in solid solution of nickel-fcc and the segregation of sulfur on and in the Ni(100) and Ni(111) surfaces are discussed. The study of sulfur in the bulk shows that the atoms S occupy the substitutional sites. The S-S and S-Ni interactions are also presented. We conclude by a discussion on the segregation and the adsorption on free surfaces
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Gupta, Tanmay. "Structural basis for the centromere localisation of the Chromosomal Passenger Complex (CPC)." Thesis, University of Edinburgh, 2017. http://hdl.handle.net/1842/29516.
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The chromosomal passenger complex (CPC: Aurora B-INCENP-Survivin-Borealin) is a key regulator of cell division whose localisation at centromeres is required for stable kinetochore-microtubule attachments and proper chromosomal segregation (Ruchaud et al. 2007; Carmena et al. 2012; van der Waal et al. 2012). Shugoshin1 (hSgo1) (via Borealin) and Histone H3 (via Survivin) have been implicated in centromeric targeting of CPC (Wang et al. 2010; Jeyaprakash et al. 2011; Tsukahara et al. 2010; Kawashima et al. 2010). Although the Survivin-Histone H3 pathway has been extensively studied, the intermolecular interactions dictating CPC-hSgo1 interactions remain unclear. My PhD work focused on characterising the molecular framework of the CPC-hSgo1 interaction using biochemical, biophysical and structural biology methods. I optimised and improved human CPC and hSgo1 recombinant protein production in an E. coli system. Post optimisation, I used Size-Exclusion Chromatography to successfully reconstitute the CPC-hSgo1 complex in vitro and further confirmed that hSgo1 possessing no modification or extra amino acids on its N-terminus can interact with Survivin and Borealin-Survivin-INCENP1-57. This suggested that the hSgo1 N-terminal tail interaction with Survivin is crucial for CPC-hSgo1 interaction. Furthermore, I conducted calorimetric binding studies to molecularly dissect the individual contributions of CPC components and their domains towards CPC-hSgo1 interaction. Towards this aim, I expressed and purified different versions of CPC and analysed their binding energetics with hSgo1. The results from these experiments clearly suggested the contribution of Borealin and INCENP towards CPC-hSgo1 interaction.
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Mahé-Gouhier, Nicole. "Etude des interactions lipase/colipase par chromatographie d'affinite conventionnelle (cac) et haute performance (cahp)." Paris 7, 1987. http://www.theses.fr/1987PA077062.
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Cette these repose sur l'application de la chromatographie d'affinite (zonale) conventionnelle (cac) et haute performance (cahp) a l'etude des interactions de la lipase (ou ses isolipases, ou sa sequence c terminale) d'une part, et la colipase, d'autre part. Les constantes de dissociations k::(d) du complexe calculees en cac et cahp sont voisines des valeurs mesurees par d'autres techniques non chromatographiques dans des conditions operatoires similaires. La cahp est une technique qui permet de determiner rapidement la stabilite du complexe lipase/colipase. L'influence de parametres physiques et physico-chimiques montre que la nature des interactions lipase/colipase est mixte, de type hydrophobe et ionique. En cahp les isolipases a et c presentent une affinite plus faible que l'isolipase b pour le cofacteur immobilise. Le peptide b, region c terminale de l'enzyme, engage des interactions specifiques avec la colipase, ce qui laisse supposer que le site d'association de la lipase avec son cofacteur se situe dans la region 336-449
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Gohard, Florence Helen. "Disrupting the INCENP-Aurora B interaction with genetically-encoded cyclic peptides." Thesis, University of Edinburgh, 2015. http://hdl.handle.net/1842/10456.
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The chromosome passenger complex (CPC) is an essential mitotic regulator with key roles in mitotic processes such as chromosome condensation, spindle dynamics, chromosome bi-orientation, the spindle checkpoint and cytokinesis. The Aurora B kinase is the CPC’s catalytic subunit. Its targeting and activation are dependent on interactions with the other components of the complex: inner centromere protein (INCENP), survivin and borealin/Dasra B. INCENP serves both as a scaffolding subunit for the CPC as a whole and as an activator of Aurora B via its highly conserved INbox domain. Aurora B is a putative anti‐cancer target; several inhibitors of the kinase are currently in clinical trials. All these are ATP-analogues targeting the kinase active site. The protein-protein interaction between Aurora B and the INCENP INbox is also essential for CPC function. Earlier studies have demonstrated that INCENP INbox mutants unable to bind and/or activate Aurora B cannot rescue lethality in the absence of endogenous INCENP. The first goal of this study was to test the in vivo effects of disrupting the interaction between endogenous wild type INCENP and Aurora B. For this, a cell-based CPC function assay was developed in HeLa cells. Using this assay, I show that expression of soluble INbox in HeLa cells produces a significant increase in multinucleated and micronucleated cells: both effects consistent with Aurora B loss of function. Expression of soluble INbox bearing the mutations W845G and/or F881A does not elicit this effect suggesting that those mutants cannot bind to Aurora B and occlude INCENP binding. The result concerning the F881A mutant contrasts with earlier reports that equivalent mutants could bind, but not activate, Aurora B. Expression of an INbox mutant lacking the C-terminal TSS motif reported to be involved in Aurora B activation but not binding has effects similar to those of the wild type INbox. Using the INbox/Aurora B interaction as a model, a secondary goal of this study was to develop and evaluate a novel approach to identify small peptides capable of dissociating intracellular protein‐protein interactions. For this, a library of small (5-9 residues long) circular peptides (CPs) mimicking the INbox was generated using the split intein circular ligation of proteins and peptides (SICLOPPS) methodology and assayed using the cell-based CPC function assay. Over two successive rounds of screening, a small number of CPs were identified that caused a significant increase in rates of multinucleated and micronucleated cells. Although statistically significant, these increases were very modest. Furthermore, due to high heterogeneity in SICLOPPS processing efficiencies, it was not practicable to compare the effects of different peptides side-by-side by transfection. The level of variation in processing efficiency – thus, CP production – was unexpectedly high and puts into question the functional complexity of more commonly used combinatorial cyclic peptide libraries derived using current SICLOPPS methodology. The results of this study are divided into three sections. The first is a methods section concerning the testing of SICLOPPS in HeLa cells and the development of a cell‐based CPC function assay. In the second, the effects of expressing soluble INbox and mutants thereof in HeLa cells are presented. The final results section presents the results of the feasibility study of the rationally-designed genetically encoded library approach.
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Senissar, Meriem. "Recherche des partenaires de l’ARN hélicase à boîte DEAD de levure Ded1." Thesis, Paris 11, 2013. http://www.theses.fr/2013PA112176.
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L’ARN hélicase à boite DEAD de la levure S.cerevisiae Ded1 est une protéine essentielle dont la fonction a été conservée au cours de l’évolution. Ses homologues fonctionnels sont impliqués dans le développement et le cycle cellulaire. Ded1 a longtemps été associée à l’étape de scanning de la région 5’UTR des ARNm au niveau de l’initiation de la traduction. Nous avons utilisé différentes approches comme les co-immunoprécipitations, des analyses de spectrométrie de masse, des tests de complémentation génétique, de séparation des complexes sur gradients de saccharose, des expériences de localisation in situ et d’enzymologie pour montrer que Ded1 interagissait physiquement avec des complexes cytoplasmique et nucléaire de liaison à la coiffe des ARNm. Nous avons également montré que Ded1 peut passer du noyau vers le cytoplasme par différentes voies d’export nucléaire. De façon intéressante, ses partenaires protéines sont capables de stimuler son activité ATPase. De plus, nous avons montré qu’il existait un lien génétique entre Ded1 et ses partenaires. Nous avons également montré que Ded1 colocalise partiellement avec ses partenaires dans des gradients de saccharose, suggérant que Ded1 pourrait être associée à certains mRNPs. Nos résultats encore préliminaires indiquent que Ded1 pourrait s’associer à d’autre ARNs coiffés. Ainsi, Ded1 pourrait remodeler les complexes associés à différentes étapes de la vie des ARN coiffésThe budding yeast DEAD-box RNA helicase Ded1 is an essential yeast protein that is closely related to a subfamily of DEAD-box proteins that are involved in developmental and cell-cycle regulation. Ded1 is generally considered to be a translation-initiation factor that helps the 40S ribosome scan the mRNA from the 5' 7-methylguanosine cap to the AUG start codon. We have used IgG pulldown experiments, mass spectroscopy analyses, genetic experiments, saccharose gradients, in situ localizations, and enzymatic assays to show that Ded1 is a cap-associated factor that actively shuttles between the cytoplasm and the nucleus. We show that Ded1 physically interacts with various cap-associated factors and that its enzymatic activity is stimulated by these factors. By using various mutated proteins, we show that Ded1 is genetically linked to these factors. Ded1 comigrates with these factors on saccharose gradients, but the peak of Ded1 sediments slightly heavier than for the other factors, which suggests that Ded1 is predominately associated with a subset of the mRNPs. Finally, purification of the protein complexes associated with Ded1 and subsequent analysis by nanoLC-MS/MS indicates that Ded1 is associated with both nuclear and cytoplasmic mRNPs. Preliminary experiements showed that Ded1 can associate with other capped RNA. We conclude that Ded1 may function as a remodeling factor that is needed to form the different complexes associated with the different processing steps of the capped RNA
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Saur, Isabelle. "Espèces organométalliques stables du germanium (II) et de l'étain II L2 (SIGMA)M14,L2(SIGMA)GeY, (L2(SIGMA)M14)xM'(CO)n-x stabilisées par le ligand BETA-diiminate L2 (SIGMA=CI, I, Me, OMe, OTf ; Y=S, Se ; M' = W,n = 6, x = 1,2 ; M' = Fe, n = 5, x=1) (L2 =PhNC(Me)CHC(Me)NPh)." Toulouse 3, 2003. http://www.theses.fr/2003TOU30097.
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Ce travail concerne l'étude d'espèces organométalliques stables du germanium et de l'étain L2M14(X), L2Ge(X)Y, (L2(X)M14)xM'(CO)n-x stabilisées par le ligand béta-diiminate L2 (X = Cl, I, Me, OMe, OTf; Y = S, Se; M' = W, n = 6, x = 1, 2; M' = Fe, n = 5, x = 1; L2 = PhNC(Me)CHC(Me)NPh). Le premier chapitre est une mise au point bibliographique sur les espèces hétéroleptiques à métal 14 de type (R)(X')M14 (M14 = Ge, Sn, X' = halogène) et les métallanechalcogénones (R)(R')M14=Y (M14 = Ge, Sn, Pb ; Y = O, S, Se, Te). Le deuxième chapitre est consacré à la synthèse et à l'étude physicochimique et structurale des germylènes hétéroleptiques halogénés L2(X)Ge (X = Cl, I). Une étude expérimentale de spectroscopie photoélectronique à rayonnement UV (S. P. E. ) et théorique (D. F. T. ) contribue à une meilleure compréhension de la structure électronique de ces espèces. Le troisième chapitre concerne les synthèses, les analyses structurales et quelques aspects de la réactivité des premiers exemples de chlorures de thio- et sélénoacides germaniés L2(Cl)Ge=Y (Y = S, Se). Le quatrième chapitre décrit les complexes L2(X)M14M'(CO)n-x. Les structures RX montrent de courtes liaisons M14-M'. Une étude théorique de ces complexes permet d'attribuer au ligand L2(Cl)Ge un fort caractère sigma-donneur et un faible caractère pi-accepteur. Le complexe méthylé L2(Me)GeW(CO)5 est également décrit. La dernière partie concerne les tentatives de synthèse des complexes cationiques [L2Ge+W(CO)5] et [(L2Ge+)2W(CO)4]. Par réaction de métathèse, le germylène L2(TfO)Ge et les complexes L2(TfO)GeW(CO)5 et (L2(Cl)Ge)2W(CO)4 ont été obtenus ; les structures des deux complexes germanium(II)-tungstène sont rapportées et analysées. Un équilibre entre une forme covalente et une forme ionique des dérivés à groupement triflate a été observé dans la pyridine. Les réactions réalisées avec AgPF6 ou NaB(Ph)4 conduisent à de nouveaux composés essentiellement issus de réactions d'hydrolyse ou de transfert de phényleThis work concerns the study of stable organometallic germanium(II) and tin(II) species L2M14(X), L2Ge(X)Y, (L2(X)M14)xM'(CO)n-x stabilized by the beta-diketiminate ligand L2 (X = Cl, I, Me, OMe, OTf; Y = S, Se; M' = W, n = 6, x = 1, 2; M' = Fe, n = 5, x = 1; L2 = PhNC(Me)CHC(Me)NPh). The first chapter reviews the group 14 element heteroleptic species (R)(X)M14 (M14 = Ge, Sn, X = halogen) and the metallanechalcogenones (R)(R')M14=Y (M14 = Ge, Sn, Pb ; Y = O, S, Se, Te). The second chapter concerns the syntheses and the physicochemical and structural analyses of heteroleptic halogenated germylenes L2(X)Ge (X = Cl, I). The halogen substitutions lead to new alkyl and methoxy germylenes. Experimental UV-photoelectron spectroscopy (U. P. S. ) and theoretical (D. F. T. ) studies contribue to a better understanding of the electronic structures of these species. .
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Ludtke, Paul Jayson. "The Role of Phosducin-like Protein as a Co-chaperone with the Cytosolic Chaperonin Complex in Assembly of the G Protein βγ Subunit Dimer." BYU ScholarsArchive, 2007. https://scholarsarchive.byu.edu/etd/1314.
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Phosducin-like protein (PhLP) has been shown to interact with the cytosolic chaperonin containing TCP-1 (CCT), and the βγ subunit dimer of heterotrimeric G proteins (Gβγ). Here we provide details obtained from cryo-electron microscopic and biochemical studies on the structure of the complex between the cytosolic chaperonin CCT and PhLP. Binding of PhLP to CCT occurs through only one of the two chaperonin rings, making multiple contacts with CCT through both its N- and C-terminal domains. In addition, we show that PhLP acts as a co-chaperonin along with CCT in mediating the assembly of the G protein βγ subunit and that assembly is dependant upon the phosphorylation of PhLP by the protein kinase CK2. Variants of PhLP lacking the CK2 phosphorylation sites, or variants with an inability to bind Gβγ block the assembly process and inhibit G protein signaling. PhLP forms a complex with CCT and nascent Gβ prior to the release of Gβγ from the ternary complex and subsequent association with the Gγ subunit to form the Gβγ dimer. In order to understand the mechanism of Gβγ dimer assembly and the role of PhLP phosphorylation in the assembly process, we provide here a method for the purification of the PhLP·CCT·Gβ ternary complex of sufficient purity for structural studies.
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Grenetier, Sabrina. "Le complexe CTD Kinase-I est requis pour le maintien de l'intégrité du locus RDN1 chez la levure S. Cerevisiae." Paris 6, 2006. http://www.theses.fr/2006PA066271.
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Chez la levure S. Cerevisiae, le complexe CTDK-I a été initialement identifié comme étant impliqué dans la transcription catalysée par l’ARN polymérase II. Au laboratoire, nous avons montré que la kinase CTDK-I est également impliquée dans la transcription catalysée par l’ARN polymérase I (Pol I) (Bouchoux et al. , 2004). La Pol I transcrit un gène unique (ADNr) codant le précurseur 35S des ARN ribosomiques. Ce gène est répété 150 fois en tandem au niveau du locus RDN1 sur le chromosome XII. Le nombre de répétitions, normalement maintenu stable, peut être affecté, notamment en cas de défaillance du système de transcription par la Pol I. Au cours de ma thèse, j’ai montré que le complexe CTDK-I est requis pour l’intégrité du locus RDN1. En effet, l’absence d’activité de ce complexe provoque systématiquement une réduction importante du nombre de copies d’ADNr présentes dans la cellule. Ce phénomène de contraction est réversible : le nombre de répétitions revient à son niveau initial après complémentation des cellules mutantes avec le gène CTK manquant. La contraction semble spécifique du locus RDN1 car elle ne touche pas d’autres régions répétées du génome. Nous avons également montré qu’elle ne dépend pas de la protéine Fob1, une protéine nucléolaire impliquée dans la recombinaison au niveau de l’ADNr. De façon intéressante, la contraction du locus RDN1 observée chez les mutants ctk ne s’accompagne pas d’une augmentation de la recombinaison au niveau de l’ADNr, et semble plutôt résulter d’évènements uniques d’excision de plusieurs copies d’ADNr. Si le mécanisme moléculaire de ce phénomène n’est pas encore élucidé, l’ensemble de nos résultats suggèrent qu’il soit causé par un défaut de la transcription par la Pol I et/ou la diminution de l’expression de Sir2, une protéine requise pour assurer la stabilité et l’homogénéité du locus RDN1.
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Beudaert, Xavier. "Commande numérique ouverte : interpolation optimisée pour l'usinage 5 axes grande vitesse des surfaces complexes." Phd thesis, École normale supérieure de Cachan - ENS Cachan, 2013. http://tel.archives-ouvertes.fr/tel-00918816.
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Le processus de fabrication des pièces usinées arrive à maturité concernant la fabrication assistée par ordinateur et la maîtrise du procédé d'usinage. Aujourd'hui, les perspectives d'améliorations importantes sont liées à l'optimisation de la commande numérique et de ses interactions avec le reste du processus de fabrication. L'objectif de cette thèse est donc de maîtriser les briques de base de la commande numérique pour optimiser le processus d'usinage 5 axes grande vitesse des surfaces complexes. La création d'une commande numérique ouverte nécessite le développement des algorithmes qui transforment le programme d'usinage en consignes échantillonnées pour les axes de la machine. La première partie des travaux consiste à rendre la géométrie suffisamment continue notamment pour les trajets interpolés linéairement en 5 axes qui présentent des discontinuités en tangence. Ensuite, l'interpolation temporelle du trajet crée la trajectoire d'usinage respectant les contraintes cinématiques et en particulier le jerk de chacun des 5 axes de la machine. L'implémentation matérielle de ces algorithmes permet de piloter une machine d'usinage grande vitesse 5 axes avec une commande numérique ouverte. Ainsi, les verrous technologiques associés aux commandes numériques industrielles sont levés et la chaîne numérique est entièrement contrôlée de la CFAO jusqu'au déplacement des axes. La maîtrise complète de la commande numérique offre la possibilité de définir exactement le trajet d'usinage à partir de la CAO sans introduire les écarts géométriques inhérents aux formats de description standards. L'interpolation de la trajectoire d'usinage directement sur la surface à usiner améliore de manière significative la qualité et la productivité de l'usinage des surfaces complexes. La commande numérique PREMIUM-OpenCNC permet la validation expérimentale de ces travaux et ouvre de nombreuses autres voies d'amélioration du processus de fabrication.
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Shafaq-Zadah, Massiullah. "Rôle du complexe adaptateur pour la clathrine AP-1 dans le maintien de la polarité épithéliale chez Caenorhabditis elegans." Phd thesis, Université Rennes 1, 2012. http://tel.archives-ouvertes.fr/tel-00683716.
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La polarité épithéliale est un processus essentiel au cours du développement d'un organisme. Ici, nous nous focalisons sur le tissu épithélial intestinal et épidermal de C. elegans pour comprendre comment la cellule maintient sa polarité en définissant un pôle apical et un pôle basolatéral. Afin d'assurer la mise en place et le maintien de cette polarité, des protéines appelées déterminants de polarité interviennent. Parmi ces déterminants, le module PAR-3/PAR-6/aPKC et CDC-42 sont des acteurs majeurs pour spécifier la polarité apicale. Nous avons montré que le complexe adaptateur pour la clathrine AP-1, un régulateur clé du trafic intracellulaire remplit une fonction inattendue dans ce processus. En effet, nous avons confirmé le rôle d'AP-1 dans le tri basolatéral observé chez les mammifères, mais de façon intéressante nous avons démontré qu'AP-1 contrôle également le tri apical d'une protéine transmembranaire ainsi que la localisation asymétrique apicale de CDC-42 et PAR-6. En effet, l'inhibition d'AP-1 cause une délocalisation basolatérale de CDC-42 et PAR-6. La perte de fonction d'AP-1 induit une conversion de la membrane latérale en membrane apicale et la formation de lumières intestinales ectopiques. La perte de fonction du complexe AP-1 induit également une létalité embryonnaire qui peut s'expliquer par le phénotype identifié dans l'épiderme. Dans cet épithélium, AP-1 contrôle l'intégrité des jonctions cellulaire et notamment le tri apical de la E-cadhérine. Nos résultats démontrent une fonction essentielle d'AP-1 dans le tri apical, directement responsable du maintien de la polarité épithéliale.
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Costes, Sylvain. "Extension de l'approche par la courbe maitresse de la prédiction des durées de vie de réseaux d'indice complexes inscrits par UV dans les fibres." Phd thesis, Université Paris Sud - Paris XI, 2013. http://tel.archives-ouvertes.fr/tel-00917592.
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L'objectif principal de cette thèse était d'examiner dans quelle mesure il est possible d'étendre l'approche de la courbe maîtresse à des composants complexes afin de déterminer des conditions de déverminage et de réaliser une prédiction de durée de vie en fonction de ces conditions de déverminage. Nous avons considéré la stabilité d'un réseau dit élémentaire (réseau carré, à pas constant et droit) puis le problème de la stabilité (selon des critères spécifiques) des composants complexes: les CDC et les monofiltres GFF. Cette thèse a permis de décrire de façon rigoureuse, puis d'utiliser le cadre de travail VAREPA pour résoudre des problèmes issus de l'industrie de télécoms. A cet effet, des séries d'études de vieillissement accéléré sur des réseaux simples et complexes ont été menées. Un protocole de mesure permettant de déterminer les incertitudes de mesure a été mis au point afin de déterminer de façon fiable des intervalles de confiance sur les prédictions de durée de vie.Nous avons étudié les cinétiques de croissance des réseaux inscrits dans une fibre dédiée à l'inscription des CDC (Coreactive). Cette étude nous a permis de montrer que la réaction prédominante à l'origine des changements d'indice de réfraction est activée par une absorption à 1 photon. D'autre part, nous avons étendu le cadre de travail utilisé pour prédire l'effacement des réseaux (VAREPA) afin de rendre compte de leurs cinétiques d'inscription. Puis nous avons cherché à déterminer les conditions de passivation et à prédire la durée de vie des réseaux déverminés en présence d'hydrogène résiduelle (procédé industriel actuel). Pour cela, nous avons établi la courbe maîtresse de réseaux photoinscrits non déverminés puis nous avons validé les conditions de déverminage et les prédictions de durée de vie en construisant une nouvelle courbe maîtresse sur des réseaux déverminés.Nous avons étudié la stabilité thermique des réseaux inscrits dans une fibre hydrogénée dédiée aux futurs monofiltres GFF dans des conditions d'inscription similaires à celles de ces composants. Nous avons utilisé les courbes maîtresses établies à partir des réseaux élémentaires (mais apodisés) simplement dégazés " à froid " (ici 2jours à 50°C puis 2 jours à 110°C). Puis, nous avons fait vieillir le profil d'indice (cœur et gaine) d'un monofiltre GFF. Puis, nous avons recalculé la réponse spectrale de ce filtre vieilli (e.g. 30jours à 200°C) et nous l'avons comparé à des mesures expérimentales. Cette approche reste générale et permet de changer les conditions de déverminage au besoin. Cette étude nous a permis de mettre en évidence que la stabilité des variations d'indice photo-induites dans le cœur dépend peu de l'amplitude initiale de la modulation pour des valeurs comprises entre quelques 10-5 et 10-3. Du fait de la présence d'une gaine optique fortement photosensible (car fortement dopée en Ge), nous avons établi les courbes maîtresses des variations d'indice photo-inscrites dans le cœur et la gaine optique pour des valeurs allant jusque 10-3 dans le cœur et 3.10-3 dans la gaine. Nous avons ainsi obtenu des courbes maîtresses présentant le même k0 (fréquence d'essai, i.e facteur pré exponentiel) mais dont la forme est légèrement différente. La stabilité des variations d'indice est meilleure dans le cœur (moins dopé en Ge) que dans la gaine photosensible. Dans un second temps, nous avons cherché à déterminer les conditions de passivation et à prédire la durée de vie des réseaux déverminés à partir des réseaux de Bragg qualifiés d'élémentaires. Pour la première fois à notre connaissance, nous avons validé de façon fiable les conditions de passivation et les prédictions de durée de vie en construisant une nouvelle courbe maîtresse sur des monofiltres GFF préalablement déverminés. Conformément à la théorie, cette courbe maîtresse présente le même k0 et une forme similaire à celle établie au moyen de réseaux non déverminés, ce qui valide la fiabilité de nos prédictions.
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Bianco, Julien. "Rôle du complexe Claspine-Timeless-Tipin dans le maintien de la stabilité du génome au cours de la réplication." Thesis, Montpellier 1, 2010. http://www.theses.fr/2010MON1T009/document.
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Il a été montré récemment que l'instabilité génétique joue un rôle central dans les étapes précoces de la tumorigenèse. Celle-ci provoquerait une activation chronique des voies ATR/CHK1 et ATM/CHK2 dans les cellules précancéreuses, entrainant l'apoptose ou la sénescence des cellules concernées. Les mécanismes de checkpoint constituant une barrière contre la progression tumorale, toute mutation affectant ce checkpoint serait ainsi sélectionnée très tôt dans le processu s de tumorigenèse et faciliterait ensuite la progression tumorale. Ce modèle met en évidence le rôle central de l'instabilité génomique et du checkpoint dans la progression tumorale.Au cours de ma thèse, je me suis intéressé au complexe Claspine / Timeless / Tipin, initialement identifié comme médiateur de la voie ATR/CHK1 et qui est donc considéré comme ayant une fonction suppresseur de tumeur. Cependant, Claspine présente aussi des propriétés oncogéniques, puisque qu'elle est surexprimée dans de nombreuses lignées tumorales et cette surexpression est importante pour la prolifération cellulaire. Nous nous sommes donc demandé comment cette protéine pouvait être à la fois un oncogène et un suppresseur de tumeur. Chez la levure, l'homologue de Claspine est impliqué dans le maintien de la stabilité des fourches de réplication, indépendamment de sa fonction dans le checkpoint. Nous proposons que dans les cellules cancéreuses cette surexpression permette une meilleure stabilité des fourches, ce qui serait très important pour répliquer efficacement un génome soumis à un stress réplicatif constant. Au cours de ma thèse, nous avons construit et caractérisé un modèle de cellulescancéreuses HCT116 dans lesquelles nous avons diminué le niveau de Claspine ou deTimeless grâce à des shRNA, sans que cela n'affecte l'efficacité du checkpoint de réplication. Nous avons pu observer dans ces cellules un ralentissement de la progression des fourches de réplication et l'apparition d'une instabilité génétique. Il semblerait que spécifiquement dans le cas de Timeless, le ralentissement de la fourche de réplication et l'instabilité génomique se manifeste surtout dans les régions du génome répliquées tardivementThe correct execution of the replication program is essential for the maintenance of genome integrity during S phase. Indeed, replication fork progression is frequently challenged by DNA lesions and by a variety of natural pause sites. Arrested forks are unstable structures, which represent a major threat for the genome integrity if they are not promptly stabilized and restarted. In response to replicative stress, cells activated the replication checkpoint to prevent collapse of stalled forks and promote fork recovery. Recent evidence indicates that spontaneous replication stress occurs in precancerous lesions and promotes the development of cancer. Identifying the origin of this replication stress would represent a better understanding of the early stages of tumorigenesis. We study the function of Claspin, a mediator of the replication checkpoint, which plays a key role in the response to replication stress. It is therefore acting as a tumor suppressor, preventing genomic instability during DNA replication. Intriguingly, recent evidence indicates that Claspin is overexpressed in different cancers and can also acts as an oncoprotein. Studies on Mrc1p, the yeast homologue of Claspin, have shown that Mrc1 is permanently associated to forks, where it forms a complex with two partners called Tof1p and Csm3p (homologues of human Tim and Tipin respectively). We have shown by DNA combing that the replicative function of Mrc1p, is critical for viability in the presence of a replication stress. In l ight of our results in yeast, we propose that the Claspin/Tim/Tipin complex may also play a direct role for the replication of human cells. If confirmed, this replication function may account for the role of this complex in the cancer process and tumor resistance to genotoxic agents commonly used in anticancer therapy
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Šojdrová, Kamila. "Studium interakcí biopolymer - tenzid pomocí mikrokalorimetrie a metod rozptylu světla." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2018. http://www.nusl.cz/ntk/nusl-376838.
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Biopolymer surfactant systems have been studied by using different physico chemical methods. As the biopolymer, it was chosen high (1400–1600 kDa), medium (250–450 kDa) and low (8–15 kDa) molecular weight sodium hyaluronate. Two cationic surfactants – cetyltrimethylammonium bromide (CTAB) and carbethopendecinium bromide (Septonex) were selected to provide polyelectrolyte complexes with oppositely charged hyaluronan. The critical aggregation concentration of the surfactant in the system was monitored by dynamic light scattering (Zetasizer Nano ZS). SEC-MALS method was used for the description of the conformation of sodium hyaluronate of different molecular weights and polyelectrolytes complexes hyaluronan surfactant after reaching the aggregation point. Isothermal titration calorimetry (ITC) was used to determine the critical aggregation concentration of the surfactant by monitoring the thermal changes accompanying the aggregation of the system. It was found out that the increasing molecular weight of hyaluronan in these systems decreases the critical aggregation concentrations and conversely.
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Rödel, Ana Paula Porto. "USO DE UM ESCORE DERIVADO DO HEMOGRAMA NA PREDIÇÃO DE RISCO DE PACIENTES SUBMETIDOS À CIRURGIA CARDÍACA COM CIRCULAÇÃO EXTRACORPÓREA." Universidade Federal de Santa Maria, 2015. http://repositorio.ufsm.br/handle/1/6027.
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Some CBC parameters have been implicated in individual susceptibility to
death, both in heart disease and cardiac surgery populations. The cellular elements
of blood are widely affected during cardiopulmonary bypass (CPB), technique used in
cardiac surgery. A Complete Blood Count called Risk Score (CBC-RS) was
calculated from the average of the deviations of the various elements of the CBC and
has been previously validated and published. The CBC-RS showed as excellent
predictor of death from all causes in large healthy and cardiovascular risk
populations. Despite the effect of CPB on the blood cells, there is no
acknowledgement from the prior assessment of this score in the surgical setting. The
aim of this study was to evaluate the role of CBC-RS in the surgical risk prediction
(mortality and morbidity) in patients undergoing cardiac surgery with CPB. For this, it
was evaluated a historical cohort of 428 patients undergoing cardiac surgery with
CPB. The individual CBC-RS was calculated using the collected blood count of
patients preoperatively. Logistic regression and statistical C analyzed the predictive
accuracy of this score. The primary endpoint was in-hospital mortality (all-cause) and
secondary outcomes included the majors and bleeding complications. In our study,
CBC-RS was a predictor of hospital mortality (OR = 1.28 for each score increments,
95% CI = 1123-1458, p <0.001) and secondary outcomes (OR = 1.208, 95% CI =
1.103 to 1.323, p <0.001). The areas under the curve (AUC) was 0.697 (p <0.001)
and 0.636 (p <0.001) for both the primary and secondary endpoints, respectively. In
multivariate analysis, after adjustment for other risk predictors (EuroSCORE II and
CPB time), the CBC-RS remained significant and was the strongest predictor of
mortality. Therefore, the CBC-RS proved to be an independent predictor of mortality
and surgical complications during hospitalization. It may be a useful tool in risk
assessment of patients undergoing cardiac surgery.Dentre os diversos parâmetros fornecidos pelo hemograma, alguns já foram implicados em aumento da suscetibilidade individual à morte, tanto em pacientes com patologias cardíacas quanto os submetidos à cirurgia cardíaca. Os elementos celulares do sangue são amplamente afetados durante a circulação extracorpórea (CEC), técnica usada nas cirurgias cardíacas. Um escore calculado a partir dos desvios da média dos diversos componentes do hemograma foi previamente validado, publicado e chamado de Complete Blood Count Risk Score (CBC-RS). O CBC-RS se mostrou excelente preditor de morte por todas as causas em grandes populações saudáveis ou com fatores de risco cardiovascular. Apesar do efeito da CEC sobre as células sanguíneas, não se tem conhecimento da avaliação prévia deste escore no contexto cirúrgico. O objetivo do presente trabalho foi avaliar o papel do CBC-RS na predição de risco cirúrgico (mortalidade e morbidade hospitalar) em pacientes submetidos à cirurgia cardíaca com CEC. Para isso, uma coorte histórica de 428 pacientes submetidos à cirurgia cardíaca com CEC foi avaliada. O CBC-RS individual foi calculado utilizando o hemograma coletado dos pacientes no pré-operatório. A acurácia preditora deste escore foi analisada através regressão logística e estatística C. O desfecho primário avaliado foi a mortalidade hospitalar (por todas as causas) e os desfechos secundários incluíram as complicações maiores e sangramento. Em nosso estudo, o CBC-RS foi um preditor de mortalidade hospitalar (OR = 1,28 por cada aumento de pontuação do CBC-RS, IC 95% = 1.123 - 1.458, p <0,001) e dos desfechos secundários (OR = 1,208, IC 95% = 1,103 - 1,323, p <0,001). As áreas sob a curva (AUC) foram 0,697 (p <0,001) e 0,636 (p <0,001) para os desfechos primário e secundário, respectivamente. Na análise multivariada, após ajuste para preditores de risco pré-operatório (EuroSCORE II) e transoperatório (tempo de CEC) conhecidos, o CBC-RS permaneceu significativo e foi o preditor de mortalidade mais forte. Sendo assim, o CBC-RS se mostrou um preditor independente da mortalidade e complicações cirúrgicas no período hospitalar, podendo representar uma ferramenta útil na avaliação de risco de pacientes submetidos à cirurgia cardíaca.
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Baron-Benhamou, Julie. "Mécanisme et contrôle de l'initiation de la traduction des ARN massagers chez les Eucaryotes." Paris 6, 2003. http://www.theses.fr/2003PA066015.
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O'Neil, Molly O'Neil. "Evaluating an Organization's Response to Vicarious Trauma in Staff and Multidisciplinary Team Members." Antioch University / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=antioch1463340871.
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Andersson, Martin. "Phase Phenomena in Polymer Networks : Empirical Studies on the Influence of Hydrophobicity, Charge Density and Crosslinks on Macroion-Induced Phase Transitions in Polyelectrolyte Gels." Doctoral thesis, Uppsala universitet, Institutionen för farmaci, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-145381.
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The thesis concerns polyelectrolyte gels in contact with oppositely charged proteins and surfactant micelles, and includes of four papers (I-IV). In paper I confocal Raman spectroscopy was introduced as a method to trace micelles and investigate the structure of gel-surfactant complexes, in phase separated gel spheres. In paper II, the binding of surfactants to microspheres (~50-100 µm) was investigated by means of a micromanipulator-assisted microscopy method. The two surfactants were found to display qualitative difference respect to degree of swelling, surfactant distribution in the gels, and the difference is discussed in terms of absence/presence of hydrophobic attraction to the polyelectrolyte gel network. Kinetics of volume change in gels were analyzed. Aggregation numbers of micelles in polystyrenesulfonate (PSS) solutions, obtained from fluorescence quenching measurements, are presented. In paper III, phase behaviour, protein assembly and diffusion, was studied in PSS gel microspheres. Interpretation of results was aided by measurements of osmotic swelling of individual gel networks, and by combining the results with studies of protein diffusion in macroscopic (cm-sized) gel spheres. Complexes formed were further analyzed with small angle x-ray spectroscopy. In paper IV phase behaviour of mixed ionic/nonionic surfactant micelles is investigated in cm-sized gel spheres. The coexistence of three phases, the formation of dense shells in the bulk of the gels and other phenomena are described for the first time, and the results are presented along with discussion on the charge-density of spherical micelles and of network induced hysteresis effects in gels. The composition and microstructure of phases are investigated by confocal Raman spectroscopy and small-angle x-ray scattering respectively. The results are interpreted with aid of highly detailed theoretical model calculations.
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Vendrell, Arasa Alexandre. "SCF cdc4 regulates msn2 and msn4 dependent gene expression to counteract hog1 induced lethality." Doctoral thesis, Universitat Pompeu Fabra, 2009. http://hdl.handle.net/10803/7153.
Full textAbstract:
L'activació sostinguda de Hog1 porta a una inhibició del creixement cel·lular. En aquest treball, hem observat que el fenotip de letalitat causat per l'activació sostinguda de Hog1 és parcialment inhibida per la mutació del complexe SCFCDC4. La inhibició de la mort causada per l'activació sostinguda de Hog1 depèn de la via d'extensió de la vida. Quan Hog1 s'activa de manera sostinguda, la mutació al complexe SCFCDC4 fa que augmenti l'expressió gènica depenent de Msn2 i Msn4 que condueix a una sobreexpressió del gen PNC1 i a una hiperactivació de la deacetilassa Sir2. La hiperactivació de Sir2 és capaç d'inhibir la mort causada per l'activació sostinguda de Hog1.També hem observat que la mort cel·lular causada per l'activació sostinguda de Hog1 és deguda a una inducció d'apoptosi. L'apoptosi induïda per Hog1 és inhibida per la mutació al complexe SCFCDC4. Per tant, la via d'extensió de la vida és capaç de prevenir l'apoptosi a través d'un mecanisme desconegut.
Sustained Hog1 activation leads to an inhibition of cell growth. In this work, we have observed that the lethal phenotype caused by sustained Hog1 activation is prevented by SCFCDC4 mutants. The prevention of Hog1-induced cell death by SCFCDC4 mutation depends on the lifespan extension pathway. Upon sustained Hog1 activation, SCFCDC4 mutation increases Msn2 and Msn4 dependent gene expression that leads to a PNC1 overexpression and a Sir2 deacetylase hyperactivation. Then, hyperactivation of Sir2 is able to prevent cell death caused by sustained Hog1 activation.
We have also observed that cell death upon sustained Hog1 activation is due to an induction of apoptosis. The apoptosis induced by Hog1 is decreased by SCFCDC4 mutation. Therefore, lifespan extension pathway is able to prevent apoptosis by an unknown mechanism.
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E, Hai-Ping, and 鄂海萍. "Theoretical study of reaction of boron atom and propylene, and the electronic structure of ruthenium(II) complexes with unsymmetric CNC’ pincer ligands and platinum(II) complexes with CCC pincer ligands." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/zccrt7.
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Chen, Po-Min, and 陳柏閔. "Theoretical study on the reaction of boron atoms with vinylacetylene and electronic structure of Pt(II) complexes with CCC pincer bis(carbene) ligands and ruthenium complexes with unsymmetric CNC’ pincer ligands." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/c8k3b7.
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碩士國立東華大學
化學系
102
The reaction of ground-state boron, B( ), with vinylacetylene (C4H4(1A’)), is investigated to explore probable routes to form products at. The isomerization and dissociation channels for the four collision complexes are found by performing the unrestricted B3LYP/cc-pVTZ and the CCSD(T)/cc-pVTZ calculations. With RRKM rate constants paths of 4 collision complexes, 41 intermediates, and 20 H-, and 9 H2- dissociated products, the most probable paths thus reaction mechanism, are determined. The corresponding rate equations are solved such that the evolutions of concentrations of collision complexes, intermediates, and products are obtained. The final products and yields are identified. We predict that complexes, c1-c4, would produce, c- CHBHC- (CCH) (p32) + H, via the collision complexes c2(c- (CH2BCH)- (CCH)). The low-energy routes for the formation of products are identified. The absorption and emission spectra of platinum and ruthenium complexes are investigated. TD-DFT methods is used with LanL2DZ basis set in calculations for ground state and excited state geometries. Franck-Condon factor is employed to simulate the spectra. The results are compared with the observed spectra.
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Chiou, Chuei-Jhih, and 邱垂誌. "Photodissociation of propanal, SOCl2 , SO2Cl2, and (SO2Cl2)2 at 248 nm, and the electronic structures of Pt(II) complexes bearing CCC pincer bis(carbene) ligands and ruthenium complexes bearing unsymmetric CNC’ pincer ligands." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/2eu5r9.
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Lo, Wei-Hao, and 羅偉豪. "Ruthenium Complexes bearing Unsymmetric CNC' Pincer Ligands Synthesis, Structures and Photophysical Properties." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/64x4mf.
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Lai, Wei-Chih, and 賴威志. "Synthesis, Structure and Catalytic Application of Ruthenium Complexes Derived from CCC-Pincer Bicarbene Ligand." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/e79z2u.
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Huang, Jhao-Jyun, and 黃昭竣. "Synthesis, Structures and Catalytic Application of Ruthenium Complexes Derived from CCC-Pincer Bis(carbene) Ligands." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/50696570909030225751.
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Vishalakshi, B. "Study Of Polyelectrolyte Complex Formation Between Carboxymethylcellulose And Vinylic Polycations : The Effect Of Structural Parameters Of The Polycations." Thesis, 1995. http://etd.iisc.ernet.in/handle/2005/1847.
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Rodrigues, Thomas Alexandre. "Preparation and characterization of hydrogels based on biopolymers: FucoPol and Chitin-glucan complex (CGC)." Master's thesis, 2020. http://hdl.handle.net/10362/115104.
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In this thesis, two polysaccharides were produced, FucoPol and chitin-glucan complex (CGC). FucoPol is an exopolysaccharide synthesised by the bacterium Enterobacter A47, composed of fucose, glucose, galactose and glucuronic acid, and also with acyl groups. CGC is a copolymer of chitin and glucan, extracted from the cell wall of the yeast Komagataella pastoris. Both biopolymers were produced using glycerol as the source of carbon, through fed-batch cultivation processes. The gel-forming capacity of these two biopolymers was recently demonstrated, and thus, the aim of this thesis was the production and characterization of FucoPol and CGC based hydrogels in terms of texture, mechanical, viscoelastic, and drug loading and release properties.
As FucoPol has the ability to form hydrogels in the presence of some metal cations, different dialysis techniques against Fe3+ solutions were performed to obtain FucoPol hydrogels, as well as different concentrations of iron solutions. On the other hand, CGC solutions obtained by freezing-thawing cycles were subjected to dialysis to induce the polymer’s spontaneous gelation. Different freeze-thaw cycles, freezing time, dialysis temperature, polymer concentration and centrifugation conditions were tested in order to optimize the final properties of CGC hydrogels. All the resulting polymeric structures exhibited high water content (above 95%). The optimized FucoPol hydrogels were more brittle and presented a reduced iron content (below 0.15%), whereas the prevalent ductileness of CGC hydrogels in all the conditions tested provided an easier characterization of texture properties, in which the hydrogel with better hardness (16547 Pa) was obtained with the higher CGC concentration. The ability of CGC hydrogels to load and release model compounds (blue food dye E133/E122, and theophylline 99%) was demonstrated for different gels. However, the drug-release capacity was lower with the increase of CGC concentration. The fact that the resulting hydrogels display different textures, rheological and drug loading and release properties support their use as promising biomaterials in distinct areas including biomedicine, bioremediation, and agriculture.
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Kuo, Yu-Ting, and 郭育廷. "Disrupting β-tubulin/CCT-β complexes induces apoptosis and suppresses migration and invasion of CL1-5 cells through MMP-2 and AKT/GSK-3β inhibition." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/4jgwn2.
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碩士國立臺灣大學
生化科學研究所
105
We have previously demonstrated that I-Trp with an iodomethyl ketone warhead to alkylate Cys354 of β-tubulin, thereby disrupting the protein-protein interaction (PPI) of -tubulin with chaperonin-containing TCP-1β (CCT-β), causes cancer cell apoptosis [1]. In this study, we found that in CL1-5 cells, I-Trp activates both ER stress related proteins and proteasome activity to eliminate the imbalance proteins loading in ER, thereby mitigating ER stress, at the onset of β-tubulin/CCT-β complexes disruption. In addition, ER stress-associated apoptotic signaling is usually accompanied with intracellular Ca2+ release and the activation of MAPKs. We also observed the elevated intracellular Ca2+ levels, activation of MAPKs and caspase over-activation. Since CL1-5 cells are a highly metastatic lung cancer cell line, we assayed for its migration/invasion in the presence of I-Trp, where there were 80% survived cells to ensure most of the cells were not killed. The experimental results demonstrate the dose-dependent inhibition of CL1-5 cell migration and invasion. Furthermore, the mechanistic studies revealed that I-Trp inhibited phosphorylation AKT, and GSK-3β of CL1-5 cells, thereby downregulating MMP-2 expression and activation. In conclusion, this study reveals a novel therapeutic strategy potential for evoking apoptotic signaling by targeting β-tubulin/CCT-β complexes, and its anti-migration/invasion activity against human lung adenocarcinoma.
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Joong, Kenneth. "Implementation of Roller Blind, Pleated Drape and Insect Screen Models into the CFC Module of the ESP-r Building Energy Simulation Tool." Thesis, 2011. http://hdl.handle.net/10012/6199.
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The concern of increasing energy consumption with depleting energy resources is ever growing. Though the solution to this problem lies in part in renewable energies, it is becoming increasingly clear that sustainable building design also plays a critical role. Controlling solar gain, for example, can greatly reduce the cooling energy consumption and lowering the peak cooling load. Having the ability to model these effects can have a substantial impact on the sizing of equipment and further reduce operational costs of a building. As a result, renewed interest has been invested by researchers and industry to promote the development and use of building simulation tools to aid in the design process.
Efforts at the University of Waterloo’s Advanced Glazing Systems Laboratory have resulted in a set of shading device models, with emphasis on generality and computational efficiency, tailored for use in building simulation. These models have been validated with measurements at the component level and with measurements performed at the National Solar Test Facility (NSTF) on a full scale window system, giving confidence to model validity. Continued research has resulted in the integration of these shading device models into ESP-r via the Complex Fenestration Construction (CFC) module, capable of modelling multi-layer glazing and shading layer systems and greatly improving the value of ESP-r as a design tool.
The objective of the current research was to implement shading device models for roller blinds, pleated drapes and insect screens to the CFC module. These would be in addition to the venetian blind model which had previously been established. A Monte-Carlo ray tracing analysis of pleated drape geometry and incident angle dependent fabric characteristics gave further confidence to the view factor or net reduction method used by the implemented models. On model implementation, a preliminary comparison was performed between a high-slat angle venetian blind, a roller drape and drapery fabric, all given the same material properties, with similar results. Further comparison was then performed using EnergyPlus shading device models to establish further confidence in the functionality of the models. Though there was some discrepancy between the results, primarily due to convective models, good agreement was found, and the effect of the shading device models on building performance was demonstrated.
The successful implementation of roller blind, pleated drape and insect screen shading models to the CFC module in ESP-r has been demonstrated in the current research. It should also be noted that the convective models for indoor shading attachments is a worthwhile topic for further research, at which point it would then be beneficial to conduct further empirical validation on the ESP-r simulation.
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Muscolino, G., and Alessandro Palmeri. "An earthquake response spectrum method for linear light secondary substructures." 2007. http://hdl.handle.net/10454/611.
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YesEarthquake response spectrum is the most popular tool in the seismic analysis and design of structures. In the case of combined primary-secondary (P-S) systems, the response of the supporting P substructure is generally evaluated without considering the S substructure, which in turn is only required to bear displacements and/or forces imposed by the P substructure (¿cascade¿ approach). In doing so, however, dynamic interaction between the P and S components is neglected, and the seismic-induced response of the S substructure may be heavily underestimated or overestimated. In this paper, a novel CQC (Complete Quadratic Combination) rule is proposed for the seismic response of linear light S substructures attached to linear P substructures. The proposed technique overcomes the drawbacks of the cascade approach by including the effects of dynamic interaction and different damping in the substructures directly in the cross-correlation coefficients. The computational effort is reduced by using the eigenproperties of the decoupled substructures and only one earthquake response spectrum for a reference value of the damping ratio.
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Nóbrega, Sónia Rodrigues. "Formulation of Chitin-glucan complex and FucoPol biopolymers particles for controlled release of fertilizers." Master's thesis, 2017. http://hdl.handle.net/10362/25834.
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The development of controlled release fertilizers (CRFs) as increased interest for the agriculture sector, in order to turn it in a more sustainable activity, diminishing nutrient losses and increasing crop productivities. The CRFs properties are improved with the use of coatings, which is mostly performed using synthetic polymers, but since they are not biodegradable causing an additional environmental concern. In order to overcome this issue synthetic problems may be substituted by biopolymers, which are biodegradable and non-toxic like chitin-glucan complex and FucoPol.
The main goal of this work was to produce nitrogen containing particles from two microbial biopolymers, chitin-glucan complex (CGC) and FucoPol. Therefore, ammonium nitrate was adsorbed to CGC particles at 15 g L-1 by submitting them to a saturated solution. There was a nitrogen uptake of 22.55 %, in 2 h contact, at pH 5.0. Hydrogel particles were produced from a FucoPol 10 g L -1 solution dissolved in 15 and 30 g L-1 of ammonium nitrate, and dropped in iron (III) chloride hexahydrate solution. The nitrogen uptake was 0.34 g L-1 and 0.53 g L-1, respectively.
The nitrogen particles release was tested in water and soil. For the nitrogen CGC particles in water at 25 ºC, a burst release was verified for ammonium (NH4+) and nitrate (NO3-) in the initial two days assay and in soil, the same happened in the initial five days assay. To the nitrogen FucoPol particles in water was observed a burst release for ammonium and nitrate in the first day and in soil in two days. The water is an extremer medium than soil, which would potentiate the burst release of the nutrients from the particles.
Lastly, the nitrogen biopolymer particles were evaluated in the germination and growth of pea (Pisum sativum) seeds. For the tests with nitrogen FucoPol particles as fertilizer it was verified a good germination and fast growth. Tests with nitrogen CGC particles presented a slower germination and growth. Therefore, nitrogen FucoPol particles have potential to be used in controlled release of nutrients.
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Farinha, Inês da Silva. "Process optimization of cell-wall polysaccharides production by Komagataella pastoris." Doctoral thesis, 2018. http://hdl.handle.net/10362/46807.
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This PhD thesis had the objective of optimizing the process developed by Pharma73 S.A. for cultivation of the yeast Komagataella pastoris to produce the cell-wall polysaccharides, chitin-glucan complex (CGC) and mannans.
A repeated fed-batch strategy was developed that resulted in the stable and reproducible production of biomass and CGC. Seven consecutive fed-batch cycles were maintained, with a daily biomass production of 119-124 g/L and a CGC volumetric productivity of 13-20 g/L.day. Reducing the dissolved oxygen (DO) level from 50 to 15% was demonstrated to result in an overall volumetric productivity of 8.67 and 10.69 g/L.day, for CGC and mannans, respectively. The CGC and mannans composition was not significantly affected by the reduction of the DO level. Medium K was developed to avoid the operational problems associated with the use of Basal Salts Medium (BSM). Medium K was successfully implemented in the repeated fed-batch process, where the CGC and mannans productivities were improved to 17.5-26 and 19.2-26.4 g/L.day, respectively, without compromising the composition of the two polysaccharides.
The downstream was optimized to obtain both polysaccharides with high extraction efficiency and purity. The optimized extraction conditions included treating the biomass with NaOH 4 M, at 84 ºC, during 4 h. The structural analysis of the polysaccharides revealed the presence of -glucans and -chitin, in the CGC, and -mannans. Both polysaccharides degraded at high temperatures: above 300 ºC for CGC and between 233-253 ºC for mannans.
The work performed in this thesis resulted in a 3.4-fold increase of the CGC productivity and the extraction of mannans from K. pastoris was demonstrated for the first time. The optimization of this production process made the process simpler and resulted in considerable savings in terms of overall production costs.
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Burrows, James Michal. "The Cost of Preanalytical Errors in the Context of Inpatient Complete Blood Count Testing." Thesis, 2012. http://hdl.handle.net/1807/42385.
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The majority of laboratory testing errors originate in the pre-analytical phase. While the causes and frequencies of pre-analytical errors are well characterized, there are few studies investigating the cost of these errors. The objective of this research was to build a model to quantify the cost of pre-analytical errors occurring during inpatient complete blood count (CBC) testing at Sunnybrook Health Sciences Centre (Sunnybrook). The resultant cost model accounts for the costs of materials, resources, and personnel-time consumed in the CBC testing process. In 2011, pre-analytical errors in inpatient CBC testing cost Sunnybrook $43,462, and represented a loss of 775 employee hours due to laboratory test repetition and error-related activities. This cost model represents the minimum cost of a pre-analytical error, as costs extraneous to the laboratory were beyond the study scope. Future studies investigating downstream effects of pre-analytical errors and the costs associated with them should be conducted.
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Stasko, Carly. "A Pedagogy of Holistic Media Literacy: Reflections on Culture Jamming as Transformative Learning and Healing." Thesis, 2009. http://hdl.handle.net/1807/18109.
Full textAbstract:
This qualitative study uses narrative inquiry (Connelly & Clandinin, 1988, 1990, 2001) and self-study to investigate ways to further understand and facilitate the integration of holistic philosophies of education with media literacy pedagogies. As founder and director of the Youth Media Literacy Project and a self-titled Imagitator (one who agitates imagination), I have spent over 10 years teaching media literacy in various high schools, universities, and community centres across North America. This study will focus on my own personal practical knowledge (Connelly & Clandinin, 1982) as a culture jammer, educator and cancer survivor to illustrate my original vision of a ‘holistic media literacy pedagogy’. This research reflects on the emergence and impact of holistic media literacy in my personal and professional life and also draws from relevant interdisciplinary literature to challenge and synthesize current insights and theories of media literacy, holistic education and culture jamming.