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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Organisation et régulation des canaux sodiques et potassiques cardiaques par les protéines MAGUK / Organization and regulation of cardiac sodium and potassium ion channels by MAGUK proteins

Eichel, Catherine 26 September 2014 (has links)
L'objectif de ce travail a été de comprendre comment les canaux ioniques sont adressés, organisés et régulés dans des domaines spécialisés de la membrane plasmique des cardiomyocytes. Parmi les partenaires des canaux, les protéines MAGUK (Membrane Associated GUanylate Kinase) sont spécialisées dans l'ancrage, l'agrégation et la formation de complexes macromoléculaires à la membrane. J'ai caractérisé pour la première fois au niveau cardiaque une de ces protéines MAGUK, la protéine CASK. CASK est localisée à la membrane latérale des cardiomyocytes et exclue des disques intercalaires, zones de conduction privilégiée dans l'axe longitudinal. À la membrane latérale, la protéine CASK est exprimée au sein du complexe costamérique dystrophine/glycoprotéines. L'inhibition de CASK entraîne l'augmentation du courant sodique INa dans les HEK293 et les myocytes cardiaques. Dans les HEK293, la microscopie à onde évanescente (TIRF) et des expériences de biotinylation ont mis en évidence que cette augmentation du courant INa est associée à une augmentation du nombre de canaux NaV1.5 à la membrane. La microscopie de conductance ionique (SICM) couplée au patch clamp en configuration cellule attachée a permis de montrer que CASK retient les canaux sodiques au niveau des crêtes et prévient leur agrégation en clusters dans les T-tubules. Enfin, l'inhibition de CASK in vivo par une stratégie reposant sur l'utilisation de virus adéno-associés (AAV) est responsable d'un allongement de la durée de dépolarisation ventriculaire et de l'apparition d'une cardiopathie dilatée. / The aim of the thesis was to understand how ion channels are addressed, organized and regulated in specialized domains of the plasma membrane of cardiac myocytes. Among these partners, the MAGUK proteins (Membrane Associated GUanylate Kinase) are specialized in anchoring, aggregation and clustering of macromolecular complexes at the plasma membrane. In particular, characterized for the first time at the level of the hearth, one of these MAGUK proteins is the CASK protein. CASK is localized at the lateral membrane of cardiomyocytes, but excluded from intercalated disks which are privilege zones of the longitudinal axial conduction. At the lateral membrane, CASK protein is expressed among the costameric dystrophin/glycoproteins complex. CASK inhibition leads to the increase in sodium current density in HEK293 cells and in cardiomyocytes. In HEK293, evanescent wave microscopy (TIRF) and biotinylation experiments pointed out that the INa increase is associated to an increase in the number of NaV1.5 channels at the plasma membrane. Scanning ion conductance microscopy (SICM) coupled to cell-attached patch-clamp has demonstrated that CASK holds together sodium channels at the crest level and prevents their aggregation into clusters in the T-tubules. Finally, inhibition of CASK, in vivo, using an adeno-associated virus strategy resulted to an increase in duration of ventricular depolarization and to the appearance of dilated cardiomyopathy.
12

Envelhecimento da cachaça com circulação forçada e aeração

Borragini, Michelle de Caiado Castro [UNESP] 04 March 2009 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:23:25Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-03-04Bitstream added on 2014-06-13T19:09:10Z : No. of bitstreams: 1 borragini_mcc_me_arafcf.pdf: 528016 bytes, checksum: cb194bfea30793f9c1000a6a2c361d48 (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Ministério da Ciência, Tecnologia e Inovação (Mcti) / O envelhecimento melhora significativamente os atributos de qualidade da cachaça, permitindo obter-se um produto compatível com as crescentes exigências dos mercados externo e interno, como se pode constatar com o aumento do consumo de cachaças com qualidade diferenciada. A redução do tempo necessário para se obter os benefícios do envelhecimento, maior obstáculo à adoção desta etapa na produção da cachaça, tem sido constantemente testada em função da economia que pode representar e também, como uma forma de estimular e difundir a adoção da prática do envelhecimento dessa bebida. Em trabalhos anteriores, amostras de cachaças bidestiladas, oriundas de um mesmo lote, foram postas a envelhecer de forma tradicional, em pequenos ancorotes de carvalho, e também utilizando-se um processo de circulação forçada com 6 ancorotes interligados em série com um reservatório de vidro, sendo então as amostras coletadas de ambos os processos comparadas. Os resultados obtidos, utilizando-se ou não nitrogênio no “headspace” do reservatório de vidro, revelaram um papel crucial da presença de ar no sistema de circulação, efeito que foi avaliado no presente estudo. Nesse sentido, foi introduzida no sistema de circulação forçada da cachaça uma etapa de aeração do sistema, realizada diariamente durante 12 minutos. Os resultados obtidos revelaram que as amostras de cachaças submetidas ao processo de envelhecimento forçado com aeração, apresentaram ao longo de seis meses, menor extração dos componentes da madeira, menor teor de acidez e tendência de melhor aceitação em relação aos atributos analisados (cor, aroma, sabor, impressão global, sabor adocicado, sabor amadeirado e agressividade), quando comparadas com as amostras submetidas ao envelhecimento tradicional, revelando que a injeção de ar no sistema de circulação forçada pode influenciar... / The aging process, improves significatively the quality sensory attributes of “cachaça” resulting final products that attend the growing marketing quality expectatives, as showed by the increasing consume of the better quality “cachaças”. The reduction of the time to obtain to aging benefits has been tried out, as a way to reduce costs and to stimulate the adoption of this practice in the “cachaças” production. In previous studies, bidistilled “cachaça” aged by the traditional way and by forced circulation through 6 small wood casks and a glass vessel, during 6 months, were compared. The results from the circulating samples, having or not nitrogen in the glass vessel headspace, showed an inportant role of the presence of air in the circulating system. In this work, the air presence effect was verified by introducing air into the circulating “cachaça”, during 12 minutes every day and comparing the samples colected during 6 months. The obtained results showed that the air injection into the system, slow down the acidity and the wood extraction, as well indicate a tendency of better acceptability of the circulating samples in relation to the sensory attributes (color, aroma, taste, global impression, sweed taste, wood taste and agressivity) when compared with that aged by the traditional way, pointing out that the air injection into the forced circulating aging system, may represent a positive... (Complete abstract click electronic access below)
13

Envelhecimento da cachaça com circulação forçada e aeração /

Borragini, Michelle de Caiado Castro. January 2009 (has links)
Orientador: João Bosco Faria / Banca: João Bosco Faria / Banca: Fernando Valadares Novaes / Banca: Natália Soares Janzantti / Resumo: O envelhecimento melhora significativamente os atributos de qualidade da cachaça, permitindo obter-se um produto compatível com as crescentes exigências dos mercados externo e interno, como se pode constatar com o aumento do consumo de cachaças com qualidade diferenciada. A redução do tempo necessário para se obter os benefícios do envelhecimento, maior obstáculo à adoção desta etapa na produção da cachaça, tem sido constantemente testada em função da economia que pode representar e também, como uma forma de estimular e difundir a adoção da prática do envelhecimento dessa bebida. Em trabalhos anteriores, amostras de cachaças bidestiladas, oriundas de um mesmo lote, foram postas a envelhecer de forma tradicional, em pequenos ancorotes de carvalho, e também utilizando-se um processo de circulação forçada com 6 ancorotes interligados em série com um reservatório de vidro, sendo então as amostras coletadas de ambos os processos comparadas. Os resultados obtidos, utilizando-se ou não nitrogênio no "headspace" do reservatório de vidro, revelaram um papel crucial da presença de ar no sistema de circulação, efeito que foi avaliado no presente estudo. Nesse sentido, foi introduzida no sistema de circulação forçada da cachaça uma etapa de aeração do sistema, realizada diariamente durante 12 minutos. Os resultados obtidos revelaram que as amostras de cachaças submetidas ao processo de envelhecimento forçado com aeração, apresentaram ao longo de seis meses, menor extração dos componentes da madeira, menor teor de acidez e tendência de melhor aceitação em relação aos atributos analisados (cor, aroma, sabor, impressão global, sabor adocicado, sabor amadeirado e agressividade), quando comparadas com as amostras submetidas ao envelhecimento tradicional, revelando que a injeção de ar no sistema de circulação forçada pode influenciar... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The aging process, improves significatively the quality sensory attributes of "cachaça" resulting final products that attend the growing marketing quality expectatives, as showed by the increasing consume of the better quality "cachaças". The reduction of the time to obtain to aging benefits has been tried out, as a way to reduce costs and to stimulate the adoption of this practice in the "cachaças" production. In previous studies, bidistilled "cachaça" aged by the traditional way and by forced circulation through 6 small wood casks and a glass vessel, during 6 months, were compared. The results from the circulating samples, having or not nitrogen in the glass vessel headspace, showed an inportant role of the presence of air in the circulating system. In this work, the air presence effect was verified by introducing air into the circulating "cachaça", during 12 minutes every day and comparing the samples colected during 6 months. The obtained results showed that the air injection into the system, slow down the acidity and the wood extraction, as well indicate a tendency of better acceptability of the circulating samples in relation to the sensory attributes (color, aroma, taste, global impression, sweed taste, wood taste and agressivity) when compared with that aged by the traditional way, pointing out that the air injection into the forced circulating aging system, may represent a positive... (Complete abstract click electronic access below) / Mestre
14

Caractérisation des sources radioactives du cycle du combustible. Applications au cycle du thorium : synthèse de l’232U en combustibles solides / Characterization of radiation sources from the fuel cycle. Applications to the thorium fuel cycle : 232U production in solid fuels

Leniau, Baptiste 09 October 2013 (has links)
Si le cycle du thorium possède plusieurs avantages par rapport au cycle U/Pu, notamment une meilleure régénération de la matière fissile en spectre thermique et une production moindre d'actinides mineurs, il présente plusieurs limites. L'une d'elles est la présence, dans le combustible thorié irradié, d'232U. Cet isotope est le précurseur d'un rayonnement γ de 2.6 MeV. Cette thèse a, en partie, pour objectif d'étudier les différents paramètres influençant la synthèse de ce noyau dans divers types de combustibles et de réacteurs.L'autre partie de ce travail consiste à estimer l'impact de cet indésirable sur la radioprotection de l'aval du cycle. Dans ce but, un ensemble d'outils, permettant le calcul des spectres énergétiques des différents rayonnements émis par la matière radioactive, a été spécialement développé. Ces outils, dont la véracité a été éprouvée par l'intermédiaire de plusieurs benchmarks, fait partie intégrante de ce travail de thèse. / The thorium cycle is a good candidate for replacing the current U/Pu cycle since the fissile nucleus of the cycle, 233U, has neutronic properties favourable to a much better regeneration of fissile material in thermal reactors. Moreover, the production of minor actinides is significantly reduced. However, the use of Thorium is only viable if the spent fuel is reprocessed to recover the fissile 233U that does not exist in nature. This reprocessing will involve a heavy industrial infrastructure, particularly since thorium based spent fuel contains small quantities of 232U that is the mother of the hard gamma emitter (208Tl) of 2.6 MeV. The goal of this thesis is, firstly, to study the parameters related to the synthesis of 232U in several kind of fuels and reactors. In a second part, the thesis focuses on the impact on radioprotection of the back end of the fuel in case of switching from the current uranium (U/Pu) cycle to the thorium (Th/U) cycle. For this last purpose, CHARS (CHAracterization of Radioactives Sources) was developed during this thesis. This code, validated by several benchmarks, handles the calculation of radiation sources in all aspects of the fuel cycle.
15

Utilizing Fluorescence Microscopy to Characterize the Subcellular Distribution of the Novel Protein Acheron

Sheel, Varun 20 October 2021 (has links)
All cells carry the genetic machinery required to commit cell suicide; a process known as programmed cell death (PCD). While the ability to initiate PCD serves a number of useful purposes during development and homeostasis, misregulation of PCD is the underlying basis of most human diseases, including cancer, autoimmunity disorders and neurodegeneration. Using the tobacco hawkmoth Manduca sexta as a model organism, the Schwartz lab at UMass has demonstrated that PCD requires de novo gene expression and has cloned many death-associated genes. One of these genes encodes a novel protein that was named Acheron after one of the rivers of the Underworld in Greek mythology. Acheron (also known as Lupus Antigen Related Protein 6; Larp6) is an RNA binding protein that mediates a number of cellular processes, including cell survival, angiogenesis, migration, and differentiation. The molecular mechanisms that mediate Acheron’s diverse roles are poorly understood, but several lines of evidence suggest that it is mediated in part by protein protein interactions and motifs that target it to different cellular compartments. In this thesis, I employed immunofluorescence and confocal microscopy to conduct two studies employing mammalian cells. The first study was to determine the subcellular localization for Acheron in normal cells and cells treated with growth factors. I found that Acheron predominantly coincides with the microtubule cytoskeleton. In our second study, I tested the hypothesis that Acheron’s binding partners BAD, Human Homolog of Ariadne-1 (HHARI) and Calcium/Calmodulin-dependent Serine Protein Kinase (CASK) colocalize with Acheron. As part of this analysis, I sought to determine if Acheron could facilitate the translocation of CASK to the nucleus. I found that Acheron localizes predominantly to microtubules, with some expression in the cytoplasm and nucleus. When Acheron and its partners are co-labeled in cycling mouse C2C12 myoblasts or human U2-OS osteosarcoma cells, Acheron did not colocalize with BAD, HHARI or CASK on microtubules. However, I found that when Acheron is driven into the nucleus with high levels of growth factors, CASK also appeared to translocate to both the nucleus and to microtubules, where it colocalized with Acheron. The data acquired through these studies should provide not only insights into the subcellular distribution of Acheron and its potential binding partners but may also help elucidate its roles in programmed cell death, differentiation, and pathogenesis in mammalian models.
16

Studium tepelných a fyzikálních vlastností skladovacích kontejnerů pro použité jaderné palivo / Spent fuel storage casks thermal and physical properties investigation

Hlatký, Pavel January 2011 (has links)
This work deals with questions of spent fuel storage casks thermal and physical properties investigation. Foundations of mathematics which are necessary for describing field of temperature are included. The work itself contains calculation methods which are split into two parts. The first one deals with simplified analytic solution and the second part solves the whole problem by the numerical computation.
17

EVALUATION OF SEISMIC DESIGN CRITERIA FOR ROCKING OBJECTS IN NUCLEAR FACILITIES

Dar, Amitabh 06 1900 (has links)
Seismic response of free standing un-anchored objects is required to be studied in Nuclear Power Plants (NPPs) for their own integrity and potential interaction with the surrounding seismically qualified safety systems. Rocking response of a rigid body subject to seismic excitation is not very well covered in the nuclear standards except for an approximate method given in ASCE 43-05 where the design basis earthquake (DBE) response spectrum for the NPPs given in the United States Nuclear Regulatory Commission (USNRC) regulatory guide 1.60 (known as NBK spectrum developed by Newmark, Blume and Kapur (1973)) is considered as seismic input. This study evaluates existing seismic design criteria for unanchored objects that are vulnerable to rocking and overturning inside nuclear power plants. The original work of Newmark et al (1973) is revisited in order to obtain the NBK spectra at unusual damping (8.4% for example), required in order to follow the ASCE 43-05 method. Eight earthquake records are selected from Newmark et al (1973) with varying Peak Ground Accelerations (PGAs) representing strong to moderate ground motions. Rocking response of rigid bodies to various earthquakes is determined by three methods: 1. The ASCE 43-05 method utilizing the NBK spectrum, 2. The ASCE 43-05 method utilizing the response spectrum of the earthquake records, and 3. solving the equations of motion of a rigid body for the earthquake records. Rocking spectra by these three methods created for eight earthquake records are compared with one another. It is concluded that the ASCE 43-05 method provides inaccurate predictions of the response. Considering the significant level of effort required to implement the ASCE 43-05 method, its inherent contradictions, and its inconsistent conservatism in estimating the seismic demands on rocking objects, it is concluded that the results obtained by nonlinear time history analysis are more accurate, reliable and less time consuming than those by the ASCE 43-05 method. The use of nonlinear dynamic analysis is recommended to obtain the pure planar rocking response of unanchored objects in nuclear facilities. / Thesis / Master of Applied Science (MASc)
18

Analysis of the cell junction proteins CASK and claudin-5 in skeletal and cardiac muscle

Sanford, Jamie Lynn 14 July 2005 (has links)
No description available.
19

New insights into the disease mechanisms of Duchenne Muscular Dystrophy through analyses of the Dystrophin, IκBβ, and CASK proteins

Gardner, Katherine Lynn 12 September 2006 (has links)
No description available.
20

Articulation as an Act of Futility: A Deconstructive Exploration of Textual Articulation as It Functions within a First-Person Narrative Structure.

Onstott, Wilson Wright 06 May 2006 (has links) (PDF)
The inability of language to convey complete meaning and truth is a central point of address for much post-structuralist literary theory and criticism. When these theories are applied to a first-person narrative structure, whether it is a work of fiction or non-fiction, certain specific incongruities arise. When a narrative seeks to recall certain events, a presupposed reexamination takes place as the narrative unfolds text comes into being. If a narractice is contructed in this way then the intent of the text then is to convey comprehensive meanings or truths of those cataloged experiences. According Deconstructive Theory, it is language's inherent nature to resist ultimate meaning. This focus on the articulation of truth is futile because meaning, like language, is always already in a state of fragmentation. This project explores five individual works from different literary traditions-ranging from the canonical to the relatively obscure. The works exhibit various approaches to articulation; including varying degrees of self-definition, personal fiction, and narrative movement toward inarticulation.

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