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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.
51

Non-unique stage-discharge relations : Bayesian analysis of complex rating curves and their uncertainties / Relations hauteur-débit non univoques : analyse bayésienne des courbes de tarage complexes et de leurs incertitudes

Mansanarez, Valentin 02 November 2016 (has links)
Les courbes de tarage complexes, qui prennent en entrée la hauteur d'eau et des variables supplémentaires, sont nécessaires pour établir les chroniques de débit des cours d'eau là où la relation hauteur-débit n'est pas univoque. Dans le même cadre bayésien, des méthodes à base hydraulique sont proposées et testées pour construire les courbes de tarage complexes et estimer leurs incertitudes : des modèles hauteur-gradient-débit (SGD) pour résoudre l'hystérésis due aux écoulements transitoires, des modèles hauteur-dénivelée-pente (SFD) pour résoudre le remous variable aux stations à double échelle, le modèle hauteur-période-débit (SPD) pour résoudre les détarages nets dus aux évolutions du lit. Chaque modèle a été appliqué à des stations hydrométriques variées et évalué grâce à des analyses de sensibilité. Pour chacune des trois sources de non-univocité de la relation hauteur-débit, les méthodes bayésiennes proposées fournissent non seulement une analyse d'incertitude quantitative mais aussi des solutions efficaces à des problèmes récurrents que posent les procédures traditionnelles pour les courbes de tarage complexes. / Complex rating curves, with stage and additional variables as inputs are necessary to establish streamflow records at sites where the stage-discharge relation is non-unique. Within the same Bayesian framework, hydraulically-based methods are introduced and tested to develop complex rating curves and estimate their uncertainties: stage-gradient-discharge (SGD) models to address hysteresis due to transient flow, stage-fall-discharge (SFD) models to address variable backwater at twin gauge stations, stage-period-discharge (SPD) model to address net rating changes due to bed evolution. Each model was applied to contrasting hydrometric stations and evaluated through sensitivity analyses. For each of the three sources of non-uniqueness in the stage-discharge relation, the proposed Bayesian methods provide not only quantitative uncertainty analysis but also efficient solutions to recurrent problems with the traditional procedures for complex ratings.
52

Discovery and development of liquid biomarkers for ovarian and lung cancer

Chudasama, Dimple January 2018 (has links)
Survival rates in cancers have improved vastly over the years. However, some survival rates remain extremely low, as is the case for ovarian and lung cancer. The lack of robust and reliable biomarkers is strongly reflected in the absence of pre-screening programs, and as such, most patients in these cancer types are diagnosed only in advanced stages, leaving few treatment options. Moreover, relapse and resistance to therapies adds to the complexities of treating these diseases, even in the era of targeted drug development. Research has shown the presence of cancer material, in the form of circulating cancer cells (CTCs) and genomic material in the blood of patients, opening the possibility of 'liquid biopsies'. Liquid biopsies allow sampling of the disease to provide phenotypic and genomic data on the cancer in real-time and on a routine basis. Moreover, they overcome obstacles currently faced by conventional tissue biopsies. In this work we evaluate the use of a novel CTC imaging flow-cytometry platform, and report the ability to characterise and quantify these cells in blood samples. Moreover, we report significantly higher levels of CTCs in cancer patients compared to controls, and found them to be associated with a poorer prognosis. In particular, in lung cancer we observe these findings even in the early stages, suggesting a potential diagnostic use for this assay. We detect a similar trend in when analysing the ctDNA and suggest the possibility of using this technique with a prognostic value in the advanced setting. We also report on the analysis of existing microarray data by use of unique gene regulatory networks to identify biomarkers of interest. RAD51AP1 was identified by this process. Clinical validation revealed an over-expression of this gene in both tissue and blood of ovarian and lung cancers. Moreover, the gene over-expression was associated with a poor overall survival. Functional analysis in vitro revealed silencing RAD51AP1 suppressed tumour growth, in addition, various tumorigenic proteins were down-regulated, whilst apoptotic and immune genes were up-regulated. These results suggest a role for RAD51AP1 as a potential therapeutic target. In this study, we also demonstrate the ability to further exploit tumour genomic material in the blood by means of RNAseq, cancer panels, and CNI scoring to identify novel markers, that play an important role in disease genesis and evolution. RNAseq analysis identified XIST as a gene up-regulated in the blood and tissue of lung cancers. The ovarian cancer panels revealed 2 unique gene signatures in the ovarian cancer patients. With the CNI analyses also highlighting chromosomal aberrations from plasma analysis of cancer patients. Collectively, the use of all these techniques and exploitation of available blood based biomarkers could see significant improvements to survival rates in these, currently devastating diseases.
53

Educational psychologists' changing role and distinctive contribution within the context of commissioned services

Winward, Victoria January 2015 (has links)
Following financial cuts introduced by the government in 2010, fewer funding and decision-making powers are held within local authorities, restricting their role as the provider of public services (Buser, 2013). As a result, the majority of local authority educational psychology teams have adopted a partially or fully-traded model of service delivery, with the aim of generating income to meet some or all service costs (Woods, 2014a). Educational psychologists have expressed concern about whether service commissioners value their distinctive contribution enough to purchase services (Fallon, Woods & Rooney, 2010). This study sought to investigate the response to trading and what impact this has had on the role of the educational psychologist, from the perspectives of service commissioners and educational psychologists. A multiple-case study design was implemented, following a mixed methods approach. Two partially-traded local authority educational psychology services were recruited. Participants from the emerging service included five educational psychologists and three small scale service commissioners. Participants from the established service included three educational psychologists, three small scale service commissioners and two large scale service commissioners. Focus groups, interviews and service brochures provided qualitative data, which were incorporated with quantitative service delivery data. All qualitative data were transcribed verbatim and analysed using thematic analysis. Findings were presented as thematic maps. Quantitative data were analysed using descriptive statistics to describe trends in service use. Findings show that the impact of trading on the role and contribution of the educational psychologist has been largely positive. Trading appears to have had a regenerating effect by creating the opportunity for an extension in the type and range of work now being completed. The findings are discussed in relation to current and future educational psychologist role and give an up-to-date insight into why the role exists, who may be willing to pay for the role and how this evolving role fits within the broader political contexts of education, special educational needs and disability.
54

Le débat institutionnel français lors du passage à l’Euro : 1998-2002. Analyse du discours et argumentation / The institutional debate on the Euro passage : 1998-2002. Discours analysis and Argumatation / Il dibattito istituzionale francese durante il passaggio all’Euro : 1998-2002. Analisi del discorso e argomentazione

Modena, Silvia 30 November 2012 (has links)
Notre projet de recherche se situe dans le cadre de l’analyse du discours en tant que discipline qui traite le fonctionnement du discours en situation. Notre propos s’inscrit donc dans la relation entre événement et discours, en particulier au sein du débat institutionnel français lors du remplacement monétaire du franc opéré par la monnaie unique, autrement dit lors du « passage à l’euro ». Ce sujeta demandé aux locuteurs de notre corpus de rechercher de façon continue l’adhésion de leurauditoire. Pour cette raison, une approche argumentative s’est tout de suite imposée à notrerecherche : nous avons ainsi mis l’accent sur l’utilisation de formes et structures intra-discursivesfinalisées à créer un climat de confiance ou de méfiance envers la monnaie unique.Notre attention s’est concentré sur l’étude des stratégies argumentatives en relation avec les positionnements et les thèses politiques et économiques défendues à l’intérieur de ce débat.Quelles stratégies de persuasion ont été employées en France pour argumenter ce passage ? À travers quels types d’arguments les locuteurs ont-ils organisé l’objectif de leur discours? Finalement, existe-il un discours sur l’euro associable à des argumentations spécifiques selon les places argumentatives occupées par ses partisans et ses opposants ? / Our research project belongs to discourse analysis as a discipline that deals with the operation of thespeech in situation. Our aim is therefore in the relationship between event and discourse,particularly in the institutional French debate when franc has been replaced by a unique currency,the Euro. The speakers of our corpus had to build confidence in Public audience. For this reason, anargumentative approach was necessary for our research. So, we have focused on the use of formsand structures intra-discursive finalized to create a climate of trust or distrust towards the uniquecurrency. Our attention is focused on the study of different forms of argument in relation to thepolitics positions and economic theses defended within this debate.What persuasive strategies were used in France to argue this passage? Through what kind ofarguments the speakers have organized the objective of their speech? Finally, is there a speech onthe euro associable with specific arguments according to the argumentative places occupied by itssupporters and opponents?
55

Cozinha de raiz : as relações entre chefs, produtores e consumidores a partir do uso de produtos agroalimentares singulares na gastronomia contemporânea

Zaneti, Tainá Bacellar January 2017 (has links)
O atual processo social de gastronomização tem deflagrado uma relação cada vez mais estreita entre a gastronomia e o meio rural. Entre as tendências da gastronomia contemporânea é crescente a demanda e o uso de ingredientes locais, tradicionais, produzidos com métodos ecológicos, que remetam ao sentido de trajetória, identidade e autenticidade, que conferem traços de singularidade aos mesmos. Essa demanda tem evidenciado, por um lado, uma maior preocupação dos comensais e chefs pela origem dos produtos e, por outro, uma (re) aproximação e (re) valorização das relações entre chefs, comensais e agricultores familiares, o que pode representar novas oportunidades de mercado para a Agricultura Familiar. Esta tese procura problematizar estas questões e tem como principal objetivo analisar como ocorrem as relações entre chefs, produtores e comensais no processo de inserção e uso de produtos agroalimentares singulares na gastronomia contemporânea, buscando perceber em que medida este consumo está estimulando novos mercados para a Agricultura Familiar e grupos tradicionais. Foram estudados quatro casos de restaurantes e Instituições que apresentavam iniciativas e práticas de relações diretas entre chefs, produtores e comensais. Para obtenção dos dados, foram realizadas entrevistas semiestruturadas com estes atores, observação participante nos restaurantes e instituições, análise de cardápios e da trajetória dos ingredientes. A mobilização dos conceitos da sociologia econômica e da análise dos dados obtidos na pesquisa de campo, proporcionaram elementos para a elaboração de conceito explicativo para o fenômeno estudado, denominado Cozinha de Raiz (embedded gastronomy). Esta se constitui a partir de cadeias gastronômicas curtas, que evidenciam relações de proximidade e enraizamento social entre os produtores, chefs e comensais e é alinhavada por produtos singulares, que tem seus padrões de qualidade e distintividade construídos e legitimados por meio das informações compartilhadas entre os atores. Essas cadeias se configuram de duas principais formas: a) Cadeia Gastronômica Curta Chefcêntrica, que tem formação horizontal, é organizada entre atores e tem o chef como elo central da cadeia; ou b) Cadeias Gastronômicas Curtas Sinérgicas, organizada de maneira vertical, mediada por instituições e não apenas pelos atores, permitindo aos consumidores e produtores maiores possibilidades de interação, conferindo maior poder de agência e autonomia para os produtores, que podem estabelecer redes tanto com os chefs, quanto com os consumidores de maneira direta. Em ambas, o chef aparece como ator social central tanto na formação destas cadeias, quanto na ressignificação dos ingredientes em direção à singularidade. Pode-se inferir que na formação horizontal, ainda que se constate a formação de uma cadeia curta, se observa, também, a formação de nichos de mercado, para poucos produtores e poucos consumidores, com baixo efeito de mudanças culturais e de desenvolvimento dos produtores. Já na formação vertical, há descentralização de poder, maior grau de relação entre os atores, maior autonomia e empoderamento dos produtores e flexibilidade para o acesso a este mercado. Assim, pode-se dizer que a Cozinha de Raiz contribui para o desenvolvimento rural, por ressocializar os produtores e relocalizar os produtos na constituição das estratégias de valorização do produtor e do produto nas cadeias gastronômicas curtas, a partir da construção de novos mercados com novos padr es de governan a. O chef cumpre um canal educativo para conscientização dos comensais sobre a importância da valorização da agricultura familiar e dos grupos tradicionais. Porém, é preciso que a atuação do chef esteja associada a políticas e a iniciativas que garantam o fortalecimento da agricultura familiar, a valorização da biodiversidade nacional e o desenvolvimento de canais curtos de comercialização. / The current social process of gastronomization has triggered an even closer relationship between gastronomy and rural areas. Among the tendencies of contemporary gastronomy is the growing demand for local, traditional ingredients, produced with ecological methods, which refer to the sense of trajectory, identity and authenticity that carries traces of singularity. This demand has triggered, on the one hand, a greater concern of the diners and chefs with the origin of the products and, on the other, a (re) oncoming and (re) valorization of the relations between chefs, diners and family farmers, which may represent new market opportunities for Family Agriculture. This thesis aims to problematize these questions and its main purpose is to analyze how the relations between chefs, producers and consumers occur in the process of insertion and use of singular agrifood products in the contemporary gastronomy, trying to understand to what extent this consumption is stimulating new markets for Family Agriculture and traditional groups. There were studied four cases of restaurants and institutions that presented initiatives and practices of direct relations between chefs, producers and diners. To obtain the data, there were conducted semi-structured interviews with these actors, participant observation in restaurants and institutions, analyses of menus and the trajectory of the ingredients. The mobilization of the concepts of economic sociology and the data analysis obtained in the field research provided elements for the elaboration of an explanatory concept for the phenomenon studied, called Embedded Gastronomy. This is based on short gastronomic chains, which show relationships of proximity and social embeddedness among producers, chefs and diners and is aligned with unique products, which have their standards of quality and distinctiveness built and legitimized through information shared between the actors. These chains are made up of two main forms: a) Chefcentric Short Gastronomic Chain, which has horizontal formation, is organized between actors and has the chef as the chain's central link; Or b) Sinergic Short Gastronomic Chains, organized in a vertical way, mediated by institutions and not only by the actors, allowing the consumers and producers greater possibilities of interaction, giving greater power of agency and autonomy to the producers that can establish networks with both the chefs, and consumers directly. In both, the chef appears as central social actor both in the formation of these chains, and in the re-signification of the ingredients towards the singularity. It can be inferred that in the horizontal formation, even if the formation of a short chain is observed, also the formation of market niches is observed, for few producers and few consumers, with low effect of cultural changes and development of the producers. In the vertical formation, there is decentralization of power, a greater degree of relationship between actors, greater autonomy and empowerment of producers, and flexibility to access this market. Thus, it can be said that the embedded gastronomy contributes to the rural development by re-socializing the producers and relocating the products in the constitution of the strategies of valorization of the producer and the product in the short gastronomic chains, from the construction of new markets with new standards of governance. The role of the chef is an educational channel for the awareness of the importance of the approximation and appreciation of Family Agriculture and traditional groups. However, the chef's role must be associated with policies and initiatives that guarantee the strengthening of Family Agriculture, of national biodiversity and the development of short marketing channels.
56

Finding Torsion-free Groups Which Do Not Have the Unique Product Property

Soelberg, Lindsay Jennae 01 July 2018 (has links)
This thesis discusses the Kaplansky zero divisor conjecture. The conjecture states that a group ring of a torsion-free group over a field has no nonzero zero divisors. There are situations for which this conjecture is known to hold, such as linearly orderable groups, unique product groups, solvable groups, and elementary amenable groups. This paper considers the possibility that the conjecture is false and there is some counterexample in existence. The approach to searching for such a counterexample discussed here is to first find a torsion-free group that has subsets A and B such that AB has no unique product. We do this by exhaustively searching for the subsets A and B with fixed small sizes. When |A| = 1 or 2 and |B| is arbitrary we know that AB contains a unique product, but when |A| is larger, not much was previously known. After an example is found we then verify that the sets are contained in a torsion-free group and further investigate whether the group ring yields a nonzero zero divisor. Together with Dr. Pace P. Nielsen, assistant math professor of Brigham Young University, we created code that was implemented in Magma, a computational algebra system, for the purpose of considering each size of A and B and running through each case. Along the way we check for the possibility of torsion elements and for other conditions that lead to contradictions, such as a decrease in the size of A or B. Our results are the following: If A and B are sets of the sizes below contained in a torsion-free group, then they must contain a unique product. |A| = 3 and |B| ≤ 16; |A| = 4 and |B| ≤ 12; |A| = 5 and |B| ≤ 9; |A| = 6 and |B| ≤ 7. We have continued to run cases of larger size and hope to increase the size of B for each size of A. Additionally, we found a torsion-free group containing sets A and B, both of size 8, where AB has no unique product. Though this group does not yield a counterexample for the Kaplansky zero divisor conjecture, it is the smallest explicit example of a non-uniqueproduct group in terms of the size of A and B.
57

Interactions entre l'ARN 23S et les protéines uL24 et uL4 dans l'assemblage de la grande sous-unité du ribosome : mesures de force par piège optique / Interactions between 23S RNA and proteins uL24 and uL4 during the assembly of the large ribosomal subunit : force measurements by optical tweezers

Geffroy, Laurent 04 December 2017 (has links)
Le ribosome est un organite essentiel de la cellule qui assure la synthèse des protéines. C'est une structure très conservée, composée d'ARN et de protéines ribosomiques organisés en deux sous-unités. Les expériences de reconstitution in vitro du ribosome d'E. coli ont montré que l'assemblage est un processus coordonné impliquant de nombreuses interactions entre les différents constituants. En particulier, les premières étapes de l'assemblage de la grande sous-unité dépendent fortement de la fixation coopérative de cinq protéines ribosomiques à l'ARN 23S, mais les mécanismes moléculaires sous-jacents sont mal connus.Cette étude à l'échelle de la molécule unique vise à préciser ces mécanismes et porte sur un fragment constitué des hélices H18, H19 et H20 du domaine I de l'ARN ribosomique 23S contenant les sites de fixation des protéines uL24 et uL4. Ce fragment d'ARN a été préparé dans une configuration qui permet la mesure de force via un double piège optique. Les courbes de force obtenues ont permis de dresser une cartographie de la stabilité des structures du fragment d'ARN.Ces cartes ont été comparées en absence et en présence des protéines ribosomiques uL24 et/ou uL4, démontrant ainsi que le fragment d'ARN est stabilisé par la fixation des protéines uL24 et/ou uL4. Leur fixation est coopérative et la présence conjointe des deux protéines sur-stabilise les structures du fragment d'ARN.Ces résultats sont discutés dans la perspective de préciser le rôle du fragment d'ARN et des protéines ribosomiques uL24 et uL4 dans l'assemblage de la grande sous-unité du ribosome. / Ribosomes are essential organelles of the cell responsible for the synthesis of proteins. Their well conserved structure made of RNA and proteins is organized into two subunits. In vitro reconstitution of E. coli ribosomes showed that their assembly is a coordinated process which involves many interactions between the components. More specifically, the early stages of the large subunit assembly depend strongly on the cooperative binding of five ribosomal proteins to the 23S RNA. The underlying molecular mechanisms however remain poorly understood.The aim of this study is to shine new light on these mechanisms at the single molecule level. It focuses on a 23S ribosomal RNA fragment composed of the helices H18, H19 and H20 in domain I which encompasses the binding sites of the ribosomal proteins uL24 and uL4. This RNA fragment has been prepared in a dumbbell configuration and force versus displacement measurements have been performed using a dual optical trap. From these measurements, a map summarizing the mechanical stability of the RNA fragment has been determined.The maps obtained in absence and in presence of the ribosomal proteins uL24 and/or uL4 have been compared consequently demonstrating mechanical stabilization of the RNA fragment induced by the binding of uL24 and/or uL4. Moreover, their binding is cooperative and when both are present, the mechanical stabilization of the RNA fragment is enhanced.These results are discussed to specify the role of the RNA fragment and proteins uL24 and uL4 in the large ribosomal subunit assembly.
58

SERVICE PROVIDERS PERSPECTIVE ON THE UNIQUE NEEDS OF SEXUALLY EXPLOITED WOMEN AND CHILDREN IN THE INLAND EMPIRE

Harrison, Ruth 01 September 2018 (has links)
The purpose of this qualitative research study was to explore and expose the needs of sexually exploited women and children. The participants were recruited from a few non-profit agencies in the Inland Empire area. This study found one of the most underlying challenge facing the participants when working with sexually exploited victims was the unavailability of resources, particularly, shortage of transitional housing for them. Another finding that featured prominently in the study was related to a need for continuous training and education for the service providers in order to stay current with trends. The study also identified the rapport building challenges faced by service providers and the risk of re-traumatization for these victims and proper types of treatment for these individuals. This study recommends that the policymakers work with other key stakeholders to provide resources to these service providers in addition to providing a favorable environment. The collaboration should also include the law enforcement agencies and the judicial officers to protect the victims from further suffering. Furthermore, the study suggests that attention should be placed on the development of awareness campaigns and stronger voices of support and advocacy for these victims.
59

Discrimination and Sequencing of Polymers with Biological Nanopores / Interaction de polymères naturels et synthétiques avec des pores protéiques

Boukhet, Mordjane 19 November 2018 (has links)
La technique de détection à l'aide de nanopores au niveau de la molécule unique est l'une des plus puissantes pour l'analyse de diverses molécules, dont les polymères biologiques et synthétiques, les protéines et les peptides, les molécules de sucre ou les nanoparticules métalliques. Ces pores peuvent également servir de plate-forme pour l'étude de phénomènes physiques et biologiques fondamentaux. Dans le cadre de l'analyse de molécules, ce travail, expérimenté en utilisant la technique de la peinture de bicouche lipidique, porte principalement sur la détection des polymères et leur utilité pour sonder les processus fondamentaux des de l'α-hémolysine et de l'aérolysine.Le premier chapitre de résultats décrit l’analyse des flux à travers l'hémolysine et l'aérolysine à l’aide des polyéthylèneglycols (PEG) et des α-cyclodextrines, ainsi que les effets des sels de KCl et de LiCl sur l'interaction des PEG avec ces pores. L'une des principales conclusions est qu'il existe un flux électoosmotique plus fort dans l'aérolysine, responsable du transport des molécules neutres, les α-cyclodextrines. La seconde constatation concerne la dynamique des PEG avec les nanopores qui semblait être fortement dépendante du sel, montrant des différences drastiques de fréquence et de durée d’interaction en fonction de la tension pour les deux sels, bien que la détection de la masse de PEG dans les deux conditions indique que la nature de l'interaction avec le pore est similaire dans les deux types de sels.Le but des travaux présentés dans le deuxième chapitre de résultats était de détecter les polymères de précision et à trouver les meilleures conditions pouvant conduire à leur séquençage avec des nanopores. Des homopolymères et copolymères de poly(phosphodiester)s ont été sondés en utilisant l'hémolysine, l'aérolysine et MspA. Le premier type de polymères étudiés contenant une amorce 3-polythymidine et une suite de comonomères de type (0) a montré une forte interaction avec les pores qui a été interprétée comme la promotion de la liaison avec les pores, due à l'amorce d’ADN simple brin, combinée à une grande flexibilité du premier type de polymères. Les polymères qui contenaient des chaînes latérales alcyne et triazole se sont révélés avoir des interactions plus complexes, mais ont interagi pendant des durées plus courtes avec les pores indiquant qu'ils étaient plus rigides. Le second type de polymères semble s’agréger en solution du fait de l’interaction entre les chaînes latérales, ce qui prouve l’importance de la caractérisation de ces molécules en solution par diffusion de rayons, dans le cadre de la détection et finalement de leur séquençage.L'étude du troisième chapitre de résultats, a porté sur la dynamique de petits oligonucléotides avec le pore d’aerolysine. Les polyadénines (A3, A4, A5) ont montré une dynamique complexe d’interaction avec le pore, qui a été étudiée par l'analyse et la quantification des différentes propriétés des événements. L'ensemble du processus s'est avéré être régi par deux sites de liaison et des barrières énergétiques à l'intérieur du pore que les molécules doivent surmonter. Ces résultats ont été combinés à un modèle cinétique qui a permis une description complète de la liaison et de la translocation (ou son non succès) des polyadénines.Le dernier chapitre des résultats décrit l’interaction de plus grandes polyadénines (A6-A7-A8-A9-A10) avec l’aérolysine. L’analyse de l'amplitude des courants des blocs induits par l'adénine à l'intérieur de ce pore montre une interaction dépendante de l'orientation des molécules avec le pore. Cette interaction dépendante de l'orientation a commencé à apparaître pour la molécule A7 et est devenue l'effet dominant pour A9 et A10. En raison de la flexibilité de l'ANDsb, cet effet n'est pas observé pour les molécules de plus petite taille (A6 et inférieures) en raison de leur possibilité de réorientation à l'intérieur du pore. / The technique of detection with nanopores at the single molecule level, is one of the most powerful method for the analysis of various molecules, of which biological and synthetic polymers, proteins and peptides, sugar molecules or metal nanoparticles. These pores can also serve as a platform for the study of fundamental physical and biological phenomenons. In the context of molecule analysis, this work, which is experimented using the technique of planar lipid bilayer painting, focuses mainly on the detection of polymers and their utility to portray fundamental processes of the α-hemolysin and aerolysin biological nanopores.The first results chapter described the probing of flows through α-hemolysin and aerolysin using polyethylene glycols (PEGs) and α-cyclodextrines, and the effects of KCl and LiCl salts on the interaction of PEGs with these pores. One main finding was that there exists a stronger electoosmotic flow in aerolysin, responsible for the transport of the neutral molecules α-cyclodextrines. The second finding was that the dynamics of PEGs with the nanopores are strongly dependent on the salt, showing drastic differences of frequency and dwell times vs. voltage for the two salts, although, the results of detection of mass of PEGs pointed to the fact that the nature of the interaction with the pore is similar in both salts.The aim of the work presented in the second results chapter, was to detect precision polymers, and find the best conditions, which can lead to their sequencing with nanopores. The homo- an copolymers of poly(phosphodiester)s were probed using α-hemolysin, aerolysin and MspA. The first type of polymers investigated which contained a 3-polythymidine primer and a sequence of comonomers of type (0) showed a strong interaction with the pores that was interpreted as the promotion of ssDNA-primer to the binding with the pore, combined to a high flexibility of the first type of polymers. The polymers which contained alkyne and triazole side chains, were found to have more complex interactions, but interacted for shorter durations with the pore indicating them to be stiffer. The second type of polymers seemed to be clustering in solution due the interaction between side chains, which proved the importance of performing characterization of these molecules in solution using wave scattering in the context of detection and ultimately sequencing.The study of the third result chapter, focused on the dynamics of small oligonucleotides with the aerolysin pore. The interaction of polyadenines (A3, A4, A5) showed complex dynamics and kinetics with pore, which was investigated via analysis of the events pattern. The whole process was found to be governed by two binding sites and energy barriers inside the pore that the molecules have to overcome. These results were combined to a developed kinetic model which allowed a complete description of the binding and translocation (or failure of it) of these polyadenines.The last results chapter described the interaction of bigger polyadenines (A6-A7-A8-A9-A10) with the aerolysin nanopore. The analysis of amplitude of currents of the adenine-induced blocks inside this pore showed an orientation dependent interaction of the molecules with the pore. This orientation dependent interaction started to be apparent for the A7 molecule and became the dominant effect for A9 and A10. Due to the flexibility of ssDNA, this effect is not observed for smaller sized molecules (A6 and below) because of their possibility of reorientation while inside the pore.
60

La solidarité du couple / The solidarity of the couple

Vaissière, Martine Françoise 21 January 2015 (has links)
Le couple constitue dans notre société une structure favorisant la solidarité. Il trouve une expression sous trois modes de vie reconnus par la loi : le mariage, le Pacs, le concubinage. Tous trois sont ouverts sans condition de différence de sexe. La loi a construit un cadre juridique à cette solidarité (très organisé, impératif, où la volonté contractuelle qui a plus de place aujourd’hui est soumise au contrôle du juge) dans le mariage, puis dans le Pacs où a été laissé une place bien plus grande à la volonté contractuelle. Elle a abandonné à la jurisprudence le soin de remédier aux conséquences que l’absence de texte relatif au concubinage pouvait avoir dès lors que l’équité et la justice le commandaient. Lorsque la loi ne les a pas prévus, c’est la jurisprudence qui a construit les mécanismes juridiques justifiant l’existence d’une solidarité du couple. La solidarité relève donc bien de la nature même du couple. Il existe une unité à la vie de couple parce que celle-ci répond à des caractéristiques, à des nécessités, qui sont identiques quel que soit le mode de vie, qu’il y ait ou non différence de sexe dans le couple. Les différenciations auxquelles aboutit la reconnaissance de plusieurs modes de vie en couple apparaissent aujourd’hui de plus en plus inadéquates. La reconnaissance d’une seule forme officielle de vie en couple constituerait le moyen d’effacer les différences dans la mise en oeuvre de la solidarité et permettrait ainsi de corriger les effets négatifs liés à la solidarité du couple. Ce cadre juridique serait constitué d’un ensemble de règles obligatoires, essentielles à la vie de couple, concernant tant les intérêts extra patrimoniaux que les intérêts patrimoniaux ; une place serait laissée à l’organisation contractuelle de la vie de couple. C’est dans les deux fonctions de la solidarité, que sont l’entraide entre les membres du couple et la garantie vis-à-vis des tiers créanciers du couple, que se construirait ce droit nouveau de la solidarité dans une union civile unique. / The couple constitutes in our company a structure supporting solidarity. It finds an expression under three lifestyles recognized by the law: the marriage, Pacs, the common-law marriage. All three are open without condition of difference in sex. The law built a legal framework with this solidarity (very organized, imperative, where the contractual will which has more room today is subjected to the control of the judge) in the marriage, then in Pacs where a place much larger was left with the contractual will. It gave up with jurisprudence the care to cure the consequences that the absence of relative text to the common-law marriage could have since equity and justice ordered it. When the law did not envisage them, it is the jurisprudence which built the legal mechanisms justifying the existence of solidarity of the couple. Solidarity thus concerns well the nature even of the couple. There exists a unit with the life of couple because this one answers characteristics, with needs, which are identical whatever the lifestyle, that there is or not difference in sex in the couple. Differentiations to which the recognition of several lifestyles in couple leads appear increasingly inadequate today. The recognition of the only one official shape of life in couple would constitute the means of erasing the differences in the implementation of solidarity and would thus make it possible to correct the negative effects related to solidarity of the couple. This legal framework would consist of a set of obligatory rules, essential with the life of couple, concerning as well the patrimonial extra interests as the patrimonial interests; a place would be left with the contractual organization of the life of couple. It is in the two functions of solidarity that are the mutual aid between the members of the couple and the guarantee with respect to the creditor thirds of the couple that would build this new right of solidarity in a single civil union.

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