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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.
101

Estudo funcional do acometimento das pequenas vias aéreas nas pneumopatias intersticiais fibrosantes / Physiological study of small airwayfunction in fibrosing interstitial lung disease

João Marcos Salge 23 February 2007 (has links)
Apesar de bem estabelecido em termos morfológicos, a repercussão funcional do envolvimento das pequenas vias aéreas nas pneumopatias intersticiais fibrosantes (PIF) permanece controversa. O presente estudo avaliou de maneira invasiva e não-invasiva (espirometria, volume de fechamento, variação da complacência dinâmica com a freqüência respiratória) a função das pequenas vias aéreas em portadores de PIF, comparando com grupo controle e correlacionando com índices morfométricos de biópsias. Os testes funcionais não diferenciaram portadores da doença dos controles quanto ao acomentimento das pequenas via aéreas e não se correlacionaram com os dados morfométricos / Although well known involvement of small airway in fibrosing interstitial lung disease based on morfologic issues, its functional consequences remains controversial. We present an invasive and non-invasive physiologic study for small airway function (pulmonary function tests, closing volume and frequency dependence of dynamic compliance) in patients with lung fibrosis. The physiological data were compared with normal controls and correlated with morfometric measurements from biopsies. Specific small airway function data could not show obstructive pattern when compared with normals, and did not correlate with morofmetric data
102

Synthesis of O-linked Carbasugar Analogues of Galactofuranosides and N-linked Neodisaccharides

Frigell, Jens January 2010 (has links)
In this thesis, carbohydrate mimicry is investigated through the syntheses of carbohydrate analogues and evaluation of their inhibitory effects on carbohydrate-processing enzymes. Galactofuranosides are interesting structures because they are common motifs in pathogenic microorganisms but not found in mammals. M.tuberculosis, responsible for the disease tuberculosis, has a cell wall containing a repeating unit of alternating (1→5)- and (1→6)-linked β-D-galactofuranosyl residues. Synthetic inhibitors of the enzymes involved in the biosynthesis of the cell wall could find great therapeutic use. The first part of this thesis describes the first synthesis of the hydrolytically stable carbasugar analogue of galactofuranose, 4a-carba-β-D-Galf, and the synthetic work of synthesising β-linked pseudodisaccharides containing carba-Galf, which were tested for glycosyltransferease inhibitory activity. The pseudodisaccharide carba-Galf-(β1→5)-carba-Galf was found to be a moderate inhibitor of the glycosyltransferase GlfT2 of M.tuberculosis. The thesis also describes how a general method towards biologically relevant α-linked carba-Galf ethers was developed. The final part of this thesis is focussed on the formation of nitrogen-linked monosaccharides without the participation of the anomeric centre. Such a mode of coupling is called tail-to-tail neodisaccharide formation. The couplings of carbohydrate derivatives via the Mitsunobu reaction are successfully reported herein. The method describes the key introduction of an allylic alcohol in the electrophile and the subsequent functionalisation of the alkene to obtain the neodisaccharide. Two synthesised neodisaccharides presented in this thesis have been sent to be tested for glycosidase inhibitory activity. / At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 3: Manuscript. Paper 4: Manuscript. Paper 5: Manuscript. Paper 6: Manuscript.
103

Remittances and the level of small and madium sized enterprise start-ups

Glommen Andersson, Elin January 2009 (has links)
This thesis within economics is examining the impact that remittances could have on the level of new small and medium sized enterprise start-ups. Remittances could be seen as a capital flow and would therefore increase the level of new SME start-ups but is this really the case? A model is developed with a panel data set over 45 countries all across the globe over a two year period. Six businesses environment variables are included in the regressions to see how the businesses environment affects the level of new SME start-ups. This model is also used when testing if the relationship between remittances and the level of new SMEs are stronger in the middle income countries than in the lower income countries. The descriptive statistics shows that both remittances and the number of new SME`s have increased from 2003 to 2005. The level of new SME`s have increased with a larger percentage share in the middle income countries relative to low income countries. The results from this thesis are somewhat difficult to interpret. Although there seems to be the case that remittances are not affecting the level of new SME start-ups when including all the countries in the same regression. As the countries are divided into two groups one can see a stronger relationship between remittances and the level of new SME started in the low income countries than in the middle income countries. One can also see that credit right and the cost of starting a new business is strongly related to the level of new SME.
104

Développement de nouveaux outils de contrôle conformationnel utilisant des interactions non-covalentes pour effectuer des macrocyclisations

Bolduc, Philippe 11 1900 (has links)
Les macrocycles ont longtemps attiré l'attention des chimistes. Malgré cet intérêt, peu de méthodes générales et efficaces pour la construction de macrocycles ont été développés. Récemment, notre groupe a développé un programme de recherche visant à développer de nouvelles voies vers la synthèse de paracyclophanes et ce mémoire présente l pluspart des efforts les plus récents dans ce domaine. Traditionnellement, la synthèse de paracyclophanes rigides est facilitée par l'installation d'un groupe fonctionnel capable de contrôler la structure de la molécule en solution (ex un élément de contrôle de conformation (ECC)). Cependant, cette approche utilisant des auxiliaires exige que le ECC soit facilement installé avant macrocyclisation et facilement enlevé après la cyclisation. Le présent mémoire décrit une méthode alternative pour guider la macrocyclisations difficile à travers l'utilisation d'additifs comme ECC. Les additifs sont des hétérocycles aromatiques N-alkylé qui sont bon marché, faciles à préparer et peuvent être facilement ajoutés à un mélange de réaction et enlevés suite à la macrocyclisation par simple précipitation et de filtration. En outre, les ECCs sont recyclables. L'utilisation du nouveau ECC est démontré dans la synthèse des para-et métacyclophanes en utilisant soit la métathèse de fermeture de cycle (RCM) ou couplage de Glaser-Hay. / Macrocycles have long attracted the attention of chemists. Despite that interest, few general and efficient methods for the construction of macrocycles have been developed. Recently our group has developed a research program aimed at developing novel routes towards the synthesis of paracyclophanes and the present thesis details the most recent efforts in this area. Traditionally, the synthesis of rigid paracyclophanes is aided by the installation of functional groups capable of controlling the solution state structure of the molecules (ie. a conformational control element (CCE)). However, this auxiliary-like approach requires that the CCE be readily installed prior to macrocyclization and easily removed following the cyclization. In the present thesis describes an alternative method to guiding difficult macrocyclizations through the use of additives as CCEs is described. The additives are N-alkylated aromatic heterocycles that are cheap, easily prepared and can be easily added to a reaction mixture and removed following the macrocyclization through simple precipitation and filtration. In addition, the CCEs are recyclable. The use of the new CCEs is demonstrated in the synthesis of para- and metacyclophanes using either ring closing metathesis (RCM) or Glaser-Hay couplings.
105

Développement d'une méthode d'alkylation pour la préparation de ligands carbènes N-hétérocycliques C₁-symétriques et synthèse de nouveaux catalyseurs pour la métathèse d'oléfines

Savoie, Jolaine January 2008 (has links)
Mémoire numérisé par la Division de la gestion de documents et des archives de l'Université de Montréal
106

Přeměny podnikatelských subjektů podle nové legislativy / Business Combinations and Transformations in Accordance with New Legislation

FRAŇKOVÁ, Kateřina January 2017 (has links)
Issues of the business combinations and transformations are very extensive and include legal, tax and accounting aspects. Legislation of the business combinations and transformations is subject of several laws and for complete and correct use, you need to put together all of them. This master thesis can be used as a methodical manual for business combinations and transformations.
107

Synthèse de nouveaux iminosucres et évaluation de leur activité inhibitrice de glycosidases / Synthesis of new iminosugar and evaluation of their inhibitory activity to glycosidase

Boisson, Julien 18 December 2014 (has links)
Le travail présenté dans ce manuscrit concerne la synthèse et une évaluation biologique de 10 nouveaux iminosucres. Les iminosucres sont une classe importante d'inhibiteurs de glycosidases (enzymes catalysant l'hydrolyse d'oligosaccharides), et l'activité inhibitrice de nos produits a été évaluée vis-à-vis d'un panel de 7 glycosidases différentes.Notre laboratoire a récemment décrit la préparation de cétonitrones cycliques polyalcoxylées à partir de cétoses tels que le D-fructose ou le L-sorbose (des sucres naturels abondants). Nous avons imaginé utiliser ces cétonitrones comme intermédiaires clés pour la synthèse de nouveaux iminosucres de structure originale, comportant un centre quaternaire en alpha de leur atome d'azote. Une partie de ce travail de thèse a consisté à améliorer la synthèse de ces cétonitrones, puis à trouver des conditions de C-vinylation diastéréosélective afin d'accéder sélectivement et efficacement à quatre pipéridines diastéréoisomères après réduction de la fonction N-hydroxylamine formée. La N-allylation de ces dernières a permis l'accès à des bis-alcénylpipéridines qui ont pu être aisément transformées en N-propylpipéridines,alpha-gem-disubstituées tétrahydroxylées après hydrogénation (des deux chaînes insaturées) et débenzylation.Les bis-alcénylpipéridines ont également été employées pour une réaction de métathèse cyclisante qui conduit au squelette indolizidine avec une double liaison en C1-C2. L'hydrogénation ou la dihydroxylation de cette double liaison, suivie par une étape de débenzylation a permis la synthèse d'indolizidines polyhydroxylées (tétra- et hexahydroxylées) inédites, substituées en jonction de cycle (position 8a). Un des composés synthétisés (une indolizidine) s'est révélé être un inhibiteur puissant et sélectif d'-glucosidases avec une concentration inhibitrice médiane de 52 nM (sur alpha-glucosidase de riz) et un mode d'inhibition peu répandu dans cette famille de molécules (inhibition non compétitive mixte). / This manuscript describes the synthesis and bioevaluation of 10 new iminosugars. Iminosugars are an important class of compounds, which can inhibit the activity of glycosidases (enzymes which catalyze oligosaccharide hydrolysis). The inhibitory activity of our products was assessed towards a panel of 7 glycosidases.Our laboratory has recently succeeded in the preparation of polyalkoxylated cyclic ketonitrones from ketoses such as D-fructose or L-sorbose (abundant natural sugars). Herein, we envisaged their utilization as precursors of new, structurally original iminosugars, bearing a quaternary center in of their nitrogen atom. We firstly improved the synthesis of these ketonitrones, and then we optimized conditions for their diastereoselective C-vinylation, in order to access selectively and efficiently four diastereoisomeric piperidines after reduction of the formed N-hydroxylamine function. The N-allylation of these piperidines gave access to the corresponding bis-alkenylpiperidines, which were readily transformed into ,alpha-gem-disubstituted tetrahydroxylated N-propylpiperidines after hydrogenation (of both unsaturated chains) and debenzylation.The bis-alkenylpiperidines were also engaged in a ring closing metathesis reaction, providing the indolizidine skeleton with a double bond in C1-C2. Hydrogenation or dihydroxylation of the latter, followed by a debenzylation step, produced original polyhydroxylated indolizidines (tetra- and hexahydroxylated), which are substituted at their ring junction (8a position). One of the synthesized compounds (an indolizidine) was found to be a highly potent and selective inhibitor of -glucosidases with a median inhibitory concentration of 52 nM (rice alpha-glucosidase) and an uncommon mode of inhibition for this class of molecules (mixed non-competitive inhibition).
108

Procedimentos de abertura e fechamento de t?picos na intera??o em sala de aula

Santos, Francisco Jos? Costa dos 24 February 2014 (has links)
Made available in DSpace on 2014-12-17T15:07:09Z (GMT). No. of bitstreams: 1 FranciscoJCS_DISSERT.pdf: 3148033 bytes, checksum: 1d6e571d5bcd941b37b01b5a7eb6cb07 (MD5) Previous issue date: 2014-02-24 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / This study is part of interactional perspective, focusing on Conversation Analysis theories, from the Textual Interactive Perspective and Text Linguistics . This research, from its guiding questions, aims at understanding the interaction between teacher and students in the process of the knowledge construction as well as at describing, analyzing and understanding aspects of topical organization speech in the classroom in elementary school, observing the opening and closing procedures of the speech topics in that particular space. Considering that the procedures for opening and closing of discursive topics occur through language marks, we tried to identify which speech marks are used in the opening and closing of the topics studied in the classroom, in interaction during the collaborative process of the discourse established between teacher and students. Therefore, this study is based on authors who analyze specific questions of the text in real context of language use: Koch (1993, 1999), Jubran et al (1991), Jubran (2006), Pine (2005), Penhavel (2010), Galembeck (2012), Barros (1991), Marcuschi (1986 , 1990, 1991 , 1998 , 1999, 2003 , 2004a), Kerbrat - Orecchioni (2006), Favero (1999, 2002) and Galv?o (2004, 2010). As a methodology of investigation, the study is focused on the postulates of ethnographic research in order to carry out data collection, through audio and video recordings which were transcribed, according to the NURC project proposal, with some adaptations. Data analysis showed that the procedures for opening and closing of the speech topics occurred by the use of discourse markers, in particular the marker "then", allowing us to understand that these elements are important in the topical organization speech, contributing to ensure textual cohesion and coherence. We conclude that the organization of the discursive topic in the classroom occurs through events that support the explicitness of the content of teaching and learning, considering the diverse necessity of an institutional academic plan, whose main objective is the construction of knowledge / Este trabalho se insere em perspectivas interacionais, com base nos pressupostos da An?lise da Conversa??o, da Perspectiva Textual Interativa e da Lingu?stica de Texto. A partir da quest?o norteadora que busca uma compreens?o acerca da intera??o entre professor e alunos no processo de constru??o do conhecimento, temos como objetivos: descrever, analisar e interpretar aspectos da organiza??o t?pica em sala de aula no Ensino Fundamental, observando os procedimentos de abertura e fechamento dos t?picos nesse espa?o espec?fico. Partindo da expectativa de que os procedimentos de abertura e fechamento dos t?picos discursivos ocorrem por meio de marcas lingu?sticas, buscamos identificar que marcas s?o usadas nas aberturas e fechamentos dos t?picos na sala de aula investigada, no transcurso das intera??es durante o processo colaborativo do discurso instaurado entre professora e alunos. Assim sendo, embasamo-nos em autores que analisam quest?es espec?ficas do texto em situa??o concreta de uso da linguagem, entre estes, Koch (1993, 1999), Jubran et al (1991), Jubran (2006), Pinheiro (2005), Penhavel (2010), Galembeck (2012), Barros (1991), Marcuschi (1986, 1990, 1991, 1998, 1999, 2003, 2004a), Kerbrat-Orecchioni (2006), F?vero (1999, 2002) e Galv?o (2004, 2010). Metodologicamente, orientamo-nos nos postulados da pesquisa etnogr?fica, a fim de realizar a coleta dos dados, atrav?s de grava??es em ?udio e v?deo, que foram transcritos, em seguida, conforme a proposta do projeto NURC, com algumas adapta??es. A an?lise dos dados ressaltados revelou que os procedimentos de abertura e de fechamento dos t?picos ocorreram pelo uso de marcadores discursivos, em especial o marcador ent?o , propiciando-nos ? compreens?o de que esses elementos s?o importantes na organiza??o t?pica, contribuindo para assegurar a coer?ncia e a coes?o textual. Conclu?mos que a organiza??o do t?pico discursivo em sala de aula acontece mediante ocorr?ncias que auxiliam a explicita??o do conte?do de ensino e aprendizagem, tendo em vista ?s diversas necessidades de um plano acad?mico institucional, cujo objetivo principal ? a constru??o do conhecimento
109

Pre-closing formulations in Meeting Talk : A Study of a Cross-functional Team Meeting at Ericsson in Stockholm

Månsson, Lisa January 2015 (has links)
Meetings are important arenas where institutional roles and relationships are acted out. Conversation analysis, a data-driven qualitative methodology utilized to study naturally occurring talk-in-interaction, was used in this study to uncover the mechanisms behind meeting talk. In a meeting shared understanding is essential and must be done in an economical manner. One interactional device to reach common agreement are formulations that summarize what has been said or draw out its relevant implication. In this essay, a sub-class of formulations, pre-closing formulations, are in focus. They serve to close the current topic and move on to the next. The aim of this thesis was to find out what kind of interactional devices are used in pre-closure formulations. The findings from the analysis of data, from a cross-functional team meeting at Ericsson in Stockholm, show how a pre-closing formulation followed by silence from the participants is the basis for an agreement. Furthermore the chair can utilize a pre-closing formulation to emphasize the topic of discussion and to influence the sense-making and thus “do” leadership. With a pre-closing formulation the meeting participants can be prepared to be held accountable for the status in a project. However, a pre-closing must not lead to a closing of the topic, the findings show how meeting participants act to continue after the chair’s candidate pre-closing formulation.
110

Préparation et caractérisation de solvants biosourcés pour des applications synthétiques et environnementales / Preparation and characterization of biosourced solvents for synthetic and environmental applications

Hayouni, Safa 16 December 2016 (has links)
De nouveaux liquides ioniques (LIs) contenant un cation phosphonium ou un cation ammonium couplé à un anion dérivé d’acides biosourcés (L-lactate, L-tartrate, malonate, succinate, L-malate, pyruvate, D-glucuronate, D-galacturonate, férulate, p-coumarate) ont été préparés suivant une réaction acido-basique simple et quantitative. Une nouvelle famille de liquides ioniques dendritiques (LIDs) a également été préparée à partir des dendrimères commerciaux (PPI et PAMAM). Les composés synthétisés ont tous été caractérisés par les méthodes usuelles d’analyses (RMN multinoyaux, SM, AE, IR) mais également par des techniques propres aux liquides ioniques (DSC, ATG, viscosité …).Ces solvants ont montré une efficacité avec la possibilité de recyclage du système catalytique [LI+ « Pd »] dans des réactions d’hydrogénations d’alcènes, de polyènes et de cétones α,β-insaturées dans des conditions douces de température et de pression. Ainsi, l’utilisation de ces LIPhs (liquides ioniques à base de phosphonium) permet d’obtenir d’excellents résultats notamment dans le cas de couplage pallado-catalysé de Heck sur 5 cycles sans perte de la réactivité.Les LIDs quant à eux ont été utilisés pour la récupération de quelques métaux lourds sous forme de cations (Cu2+, Ni2+, Pb2+, Cd2+, Ag+) dans des solutions aqueuses. Quelle que soit la nature du LI utilisé (hydrophile ou hydrophobe), d’excellents taux d’extraction sont obtenus sans modification du pH initial. / New biomass derived ionic liquids (ILs) containing phosphonium or ammonium cations with natural organic derived anions (L-lactate, L-tartrate, malonate, succinate, L-malate, pyruvate, D-glucuronate, D-galacturonate, férulate, p-coumarate) were easily prepared with good yields. Other dendritic ionic liquids (DILs) were also obtained from commercial PPI or PAMAM dendrimers. These DILs are containing NTf2 or BF4 anions. The characterization of all ILs was realized through classical NMR, IR, MS and elemental analysis techniques; their viscosity and ATG parameters were also determined.These new solvents proved good performance and recyclability for the selective Pd-catalyzed hydrogenation of alkenes, polyenes and also for the enantioselective hydrogenation of α,β-unsaturated ketones under mild temperature and hydrogen pressure conditions. Furthermore, they showed excellent performances (reaction yields and recycling) for the Heck coupling reaction.Finally, the hydrophilic and hydrophobic DILs were used for removal of metallic ions (Cu2+, Ni2+, Pb2+, Cd2+, Ag+) present in contaminated water and the results of the study proved their excellent catching behaviour.

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