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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.
281

Estudo sobre a utiliza????o da informa????o gerencial nas decis??es de posicionamento estrat??gico : uma pesquisa na ind??stria de cal??ados de Ja??-SP

Carraro, Nilton Cesar 30 July 2007 (has links)
Made available in DSpace on 2015-12-03T18:35:09Z (GMT). No. of bitstreams: 1 Nilton_Cesar_Carraro.pdf: 896223 bytes, checksum: 8c0daf04f6bcf3e81b87cc842356e7fd (MD5) Previous issue date: 2007-07-30 / The study of the use of the management information in the decisions of the strategic disposition by the footwear Industry of Ja?? - SP - investigates the use of the management information in a systemic process. The population of the research was limited to the formal footwear Industry comprehending Ja?? and neighbouring cities, both located in the center-west of S??o Paulo State, which during several decades, cultivated this economical activity causing Ja?? to be renowned as the Women Footwear National Capital. As an incentive to the research the great entering of hand-made Asian products, mostly footwear, brings about some apprehension about the local Industry competitiveness condition, at first taking the research to revision of the techniques of strategical management which could make the systemic use of the management information evident in the search for competition advantages. Expecting to create a census, questionaires were both handed out as well as made available in the Internet, where only 41 Industries answered to the calling, translating what would be a census into an aleatory sample. After this gathering, the questionaire involving 24 questions on the structure and organization aspects, was then treated statistically, with the creation of frequency tables, to define the entries for the treatment of the Chi-Squared tests, homogeneity and independency - crossing a series of variants and testing the results obtained. In the search for the strategic disposition, it was possible to make it evident that factors related to the experience of the entrepreneurs, period of existence of the firms, and the fact of belonging to a footwear center, are the main tools in the generation of management information capable to help in the decisions of strategic disposition, however, issues such as the low number and qualification of administrative employees impair the organization structure of these Industries, jeopardizing the use this management information. Negative factors to the research were made clear through the analysis which points out the lack of planning and strategic controlling, the lack of information about competition, the lack of indicators which proves the business performance and mostly the lack of knowledge about skills and competences which must be created to guarantee the profits and the continuity of its future activities. As a main result of the research, it is understood that this area of business has management information, however, not enough to bear the necessary decisions in the strategic disposition of this Industry. / O estudo sobre a utiliza????o da informa????o gerencial nas decis??es de posicionamento estrat??gico pela ind??stria de cal??ados de Ja?? - SP procura investigar o uso das informa????es gerenciais dentro de um processo sist??mico. Delimitou-se a popula????o da pesquisa ?? ind??stria formal de cal??ados que comp??e o munic??pio de Ja?? e cidades circunvizinhas, ambas localizadas na regi??o centro-oeste do Estado de S??o Paulo, que ao longo de v??rias d??cadas cultivaram essa atividade econ??mica levando Ja?? a ser reconhecida como a Capital Nacional do Cal??ado Feminino. Como est??mulo ?? pesquisa, a grande entrada de produtos manufaturados vindos da ??sia, principalmente o cal??ado, gera uma inquieta????o sobre a condi????o de competitividade da ind??stria local, conduzindo a principio a pesquisa para revis??o de t??cnicas sobre gest??o estrat??gica que pudessem evidenciar o uso sist??mico da informa????o gerencial na busca de vantagens competitivas. Com a expectativa de se criar um censo, foram distribu??dos question??rios tanto pessoalmente como por meio da internet, onde apenas 41 ind??strias responderam ao chamado, traduzindo o que seria um censo em uma amostra aleat??ria. Ap??s essa coleta, o question??rio envolvendo 24 quest??es, abordando estrutura e aspectos organizacionais, passou a ser tratado estatisticamente, com a cria????o de tabelas de freq????ncia para defini????o das entradas para tratamento dos testes qui-quadrado, homogeneidade e independ??ncia - cruzando uma s??rie de vari??veis e testando os resultados obtidos. Na busca pelo posicionamento estrat??gico, pode-se evidenciar que fatores ligados ?? experi??ncia dos empres??rios, tempo de exist??ncia das empresas, e o fato de pertencer a um p??lo cal??adista, s??o as principais ferramentas na gera????o de informa????es gerenciais com poder de auxiliar nas decis??es de posicionamento estrat??gico, no entanto, quest??es como a baixa quantidade e qualifica????o dos empregados do setor administrativo prejudicam a estrutura organizacional dessas ind??strias, comprometendo negativamente a utiliza????o dessa informa????o gerencial. Fatores negativos a pesquisa foram evidenciados por meio das an??lises que apontam a falta de planejamento e controle estrat??gico, a falta de informa????es sobre a concorr??ncia, falta de indicadores que comprovam o desempenho empresarial, e principalmente a falta de conhecimento sobre habilidades e compet??ncias que devem ser geradas no intuito de garantir os lucros e continuidade de suas atividades futuras. Como resultado principal da pesquisa, percebe-se que o setor possui informa????es gerenciais, por??m, elas n??o s??o suficientes para suportar decis??es necess??rias no posicionamento estrat??gico dessa ind??stria.
282

Comportamiento ambiental de lodos de fundición estabilizados/solidificados

Coz Fernández, Alberto 13 July 2001 (has links)
El objetivo de esta tesis ha sido el tratamiento de un residuo (lodo de fundición) procedente del lavado húmedo de los gases del horno fusor. Para ello, se ha evaluado la peligrosidad del residuo y, posteriormente, se han estudiado diferentes tratamientos previos al vertido y se ha realizado su evaluación ambiental. El lodo de fundición es un residuo ecotóxico, debido principalmente a la alta concentración de cinc y a la carga orgánica (fenoles) del mismo, pudiéndose establecer relaciones matemáticas entre la ecotoxicidad y la concentración de cinc y fenoles, tanto en el residuo original como en los productos finales. Entre las diferentes tecnologías de tratamiento, destacan los procesos de estabilización/solidificación con cal o cemento como agente aglomerante, por su elevado interés en residuos de carácter tóxico mixto: orgánico e inorgánico. Se ha llevado a cabo un estudio exhaustivo de los diferentes aditivos utilizados en dichos procesos y se han desarrollado diferentes formulaciones cal o cemento y aditivos/residuo con el fin de cumplir los parámetros ambientales, concluyéndose con la relación existente entre formulación y evaluación ambiental y obteniendo una patente de invención. / The aim of this work has been the study of the treatment of foundry sludge coming from after wet cleaning of gases of the furnace in foundry activities. Previously, the hazardous of the waste material has been evaluated. Later, different treatments have been studied and the environmental evaluation have been conducted. Foundry sludge is an ecotoxical waste due to inorganic (basically zinc) and organic (phenols) pollutants, being able to establish mathematical relationships between the ecotoxicity and the concentration of zinc and phenols, both in waste and end-products. Among the different technologies for the treatment, stabilisation/solidification processes with lime or cement as binders are very interesting technologies for waste of mixed character (organic and inorganic). An exhaustive study of different additives used in these processes has been carried out and different formulations have been developed in order to inertise the waste materials, concluding with the relationships between formulation and environmental evaluation and obtaining a patent.
283

FATIGUE CHARACTERIZATION OF RISERS AND PIPELINES UNDER REALISTIC VARIABLE AMPLITUDE LOADING AND THE INFLUENCE OF COMPRESSIVE STRESS CYCLES

Iranpour, Mohammad 11 January 2013 (has links)
One of the most prominent factors affecting the performance and longevity of risers is vortex induced vibration (VIV), which can cause severe fatigue damage, especially in risers used in deep waters. The available approaches for analyzing VIV induced fatigue in risers mainly focus on the VIV aspect of the problem; indeed less attention has been paid on the effect of VIV on a riser’s fatigue life and in prediction of fatigue life using various models. This dissertation first demonstrates how one can characterize fatigue of pipes and risers using an equivalent plate specimen as opposed to using a pipe specimen, thereby simplifying the task, yet obtaining good accuracy. Actual variable amplitude loadings (VAL) are used to study the fatigue crack growth in risers’ material with a focus on the various influencing parameters. Extensive experimental investigations are performed, followed by analytical and computational nonlinear finite element analyses. It is shown that the higher harmonics do cause significant fatigue damage, thus their influence should not be ignored. The influence of load interaction effects is also investigated, focusing on the fatigue crack growth retardation effects due to tension overloads, as well as the acceleration effects due to compression underloads. The crack closure concept is then used to explore into both the fatigue retardation and acceleration effects within a VAL scenario. An effective method for calculation of the stress intensity factor is proposed, which considers only the tensile portion of the stress range, while proposing another effective approach for accounting for the influence of compressive stress cycles. Moreover, a two-parameter approach is used in this dissertation, relating the fatigue crack growth rate (FCGR) to the crack tip opening displacement (CTOD). It is shown that the CTOD provides adequate information for calculating the FCGR under VAL, and it can be effectively used to account for the influence of the compressive stress cycles. The experimental investigation also considers the retardation effect resulting from the applied peak tensile overload cycles (TOLC) and the influence of various so-called “clipping” levels, demonstrating the significant influence of the TOLC on crack growth retardation in VAL.
284

Oceňování v podmínkách českých účetních předpisů a IFRS na příkladu konkrétní účetní jednotky. / Assessing in the terms of the czech accounting standards and IFRS - example some accounting entity.

VACKOVÁ, Lenka January 2013 (has links)
The aim of this work is to analyse the methods of valuation in accounting in accordance with Czech Accounting Legislation and International Financial Reporting Standards. This thesis compares different approaches on the example of the specific accounting entity. The company is called E.ON Czech Republic, s. r. o. The theoretical part of the thesis describes accounting systems and defines some of the international standards. The practical part of the thesis characterizes the accounting entity and describes the found differences. The next point is the subsequent comparison and evaluation.
285

Material para construção civil a partir de lodo de estação de tratamento de água, lama de polimento de mármore e resíduo de produção de cal / Construction material from water treatment sludge, marble polish mud and lime production waste

Hackbart, Fernanda Meireles 11 December 2015 (has links)
O crescimento populacional acelerado é o grande motivador para o desenvolvimento do setor da construção civil e o aumento na demanda por água potável, tendo como consequência, um aumento gradativo na geração de resíduos sólidos. Dessa forma, este trabalho foi realizado com o intuito de reciclar resíduos industriais e municipais incorporando-os em materiais para a construção civil. O compósito produzido a partir de lodo de estação de tratamento de água e lama de polimento de mármore, aplicando resíduo de produção de cal como ligante, foi avaliado quanto ao seu desempenho mecânico e sua estrutura morfológica. As matérias-primas foram caracterizadas quanto sua composição química, mineralógica,morfológica, granulométrica e, também, o teor de umidade. Com os materiais caracterizados, foram desenvolvidas nove composições variando-se o teor de lodo de estação de tratamento de água entre 25 e 50%, o teor de lama de polimento de mármore entre 35 e 50% e o resíduo de produção de cal entre 10 e 30%. Os compósitos foram submetidos a ensaios de resistência mecânica, absorção de água, análise química, mineralógica e morfológica. Os materiais desenvolvidos apresentaram, no 3° dia de cura, valor de resistência mecânica máxima de 4,65 MPa, no 7° dia 6,36 MPa, no 14° dia 6,74 MPa, no 28° dia 5,98 MPa, no 60° dia 8,52 MPa, no 90° dia 11,75 MPa e no 180° dia 12,06 MPa. Os valores de absorção de água aos 28 dias de cura variaram de 16,27 a 26,32% e aos 90 dias, de 13,57 a 23,56%. / The rapid population growth is the great motivator for the development of the construction industry and the increased demand for drinking water, resulting in a gradual increase in the generation of solid waste. Thus, this work was carried out in order to recycle industrial and municipal wastes incorporating them into materials for civil construction. The composite produced from water treatment sludge and marble polishing mud, applying lime production waste as a binder, was evaluated for its mechanical performance and its morphological structure. The raw materials were characterized for their chemical composition, mineralogy, morphology, particle size and also the moisture content. With the featured materials nine compositions have been developed varying the content of the water treatment sludge between 25 to 50%, marble polishing mud between 35 to 50% and the lime production waste between 10 to 30%. The composites were subjected to mechanical strength tests, water absorption, chemical and mineralogical composition and morphology. The developed materials presented, on the 3rd day of hydration, maximum strength value of 4.65 MPa, the 7th day 6.36 MPa, on the 14th day 6.74 MPa, the 28th day 5.98 MPa, on the 60th day 8.52 MPa at 90th day 11.75 MPa and 180th day 12.06 MPa. The water absorption values after 28 days of hydration ranged from 16.27% to 26.32% and after 90 days, from 13.57% to 23.56%.
286

Utilização de resíduos de argamassa, lodo de anodização de alumínio e cal para a formação de um novo compósito / Use of argamassa residues, anodization sludge of aluminum and lime for the formation of a new composite

Molinetti, Andréa 01 August 2016 (has links)
Os resíduos decorrentes da construção civil apresentam, na maioria das vezes, a predominância de materiais inertes e passíveis de reaproveitamento, que não tem em grande parte uma finalidade. Esta dissertação apresenta uma abordagem sobre destinação correta dos resíduos, utilizando resíduos de argamassa, lodo de anodização de alumínio e cal para a formação de um novo compósito. O maior objetivo desta dissertação é caracterizar os materiais como componentes de novos compósitos para a construção civil, além de identificar novas composições (ao todo são 13 composições) atendendo as normas e leis existentes, analisar os processos físico-químicos, determinar as propriedades mecânicas e adaptar tecnologias existentes no processo de fabricação, além de destinar sem danos ambientais todas as matérias primas. Para análises físico-químicas e mecânicas foram estudados os seguintes parâmetros: resistência uniaxial média, absorção de água, densidade aparente, retração linear, microscopia eletrônica de varredura (MEV), espectrometria por energia dispersiva, difração de raios-X e espectrometria de fluorescência de raios-X (FRX). Dentre as 13 composições foram escolhidas as composições 4 e 11 para analisar mais o comportamento físico-químico. A resistência à compressão média uniaxial, aos 90 dias da composição 11 alcançou 9,18 MPa, com coeficiente de absorção de água de 12%, a retração foi de 1,53% e a densidade ao longo de 180 dias de cura variou apenas 4%. Os estudos físico-químicos identificaram a presença de Carbono, Sódio, Magnésio, Alumínio, Silício e Cálcio na composição 11, e através do MEV e FRX foi possível identificar que se trata de uma estrutura amorfa. Através desses estudos propõe-se alternativas que sejam revertidas em vantagens sociais e ambientais, tais como a fabricação de blocos vazados de concreto simples para alvenaria sem função estrutural, blocos cerâmicos para alvenaria de vedação, tijolos maciços para a alvenaria em relação a categoria A, entre outros. / Waste from the construction, have in most cases the predominance of inerts materials and insusceptible reuse, which has a few purpose. This dissertation presents an approach on the correct disposal of this waste, using mortar residue, anodizing aluminum sludge and lime to form a new composite. The main objective of this project is to characterize the materials as components of new composites for the construction industry, and identify new compositions (they are 13 compositions) meet the existing standards and laws, analyze the physical and chemical processes, determine the mechanical properties and adapting existing technologies in the manufacturing process, beyond to appropriate correctly without environmental damage for all the materials. For physical-chemical and mechanical analysis, the following parameters were studied: resistance average uniaxial, water absorption, apparent density, linear retraction, environment-scanning electron microscopy, energy dispersive x-ray, x-ray diffraction and x-ray fluorescence. Between the 13 compositions, chosen compositions 4 and 11 to analyze the behavior. The average uniaxial compressive strength at 90 days composition 11 reached 9,18 MPa with 12% water absorption coefficient, the shrinkage was 1,53% and the density over 180 days varied only 4%. The physic-chemical studies have identified the presence of Carbon, Sodium, Magnesium, Aluminum, Silicon and Calcium in the composition 11 and about scanning electron microscopy and XRF identified that it is an amorphous structure. Through these studies, it was possible to propose alternatives that are reversed in social and environmental benefits, such as the manufacture of simple concrete hollow blocks brickwork without structural function, ceramic blocks for sealing brickworks and solid bricks for brickworks in relation to category A, among others.
287

Desenvolvimento de novos compósitos destinado a materiais de construção civil, com base em resíduos industriais de solo de decapagem, lodo e sedimentos de dragagem do porto de Antonina e cal virgem comum

Pan, Roberto Chun Yan 09 June 2015 (has links)
Pesquisa realizada para analisar o compósito de solo de decapagem (SD) considerado resíduos nas jazidas de minérios, em especial de calcário do município de Almirante Tamandaré, da Região Metropolitana de Curitiba neste trabalho, juntamente com o lodo e sedimentos de dragagem marinha do Porto de Antonina, no Estado do Paraná, e o uso cal virgem comum, como aglomerante pertencente à região de Almirante Tamandaré. Foram utilizados vários teores dos materiais para a determinação de 12 (doze) compósitos. Para o solo de decapagem os teores variaram entre 30% a 60%, para o material de dragagem os teores variaram entre 20% a 50% e o teor de aglomerante de cal virgem comum variou entre 15% a 30%. Foram moldadas idades de cura de 3 dias, 7, 14, 28, 60, 90, 180 e 365 dias. O aumento da resistência à compressão durante a cura foi proveniente das reações químicas das partículas sólidas das matérias-primas em ambiente alcalino gerando novas formações amorfas. Também foram analisados os materiais nos métodos de MEV com EDS, DRX e FRX, para a obtenção da composição química e formação estrutural dos novos compósitos. Todos os resultados da resistência à compressão uniaxial, com 28 dias de cura ao meio ambiente das 12 (doze) composições, obtiveram resultados médios de 7,7 MPa, atendendo satisfatoriamente a norma NBR 7170:1983 que determina a resistência à compressão igual ou acima de 4,0 MPa, destinada à produção de materiais de construção para alvenaria de vedação, sem fins estruturais. Comprovando o uso desses compósitos em materiais de construção civil, principalmente para os segmentos de blocos ou tijolos de vedações, sem fins estruturais, sem a necessidade de cozimento ou empreendimento de energia calorífica para a cura das peças, contribuindo para o meio ambiente e a sustentabilidade ambiental. / Research conducted to analyze the composite with pickling soil (SD), considered waste in mineral deposits, especially of limestone in the city of Almirante Tamandaré, the Metropolitan Region of Curitiba in this work, along with the sludge and marine dredging sediment from the Port of Antonina, State of Paraná, and use the common quicklime as binder belonging to the same region of Almirante Tamandaré. Various amounts of materials were used for the determination of twelve (12) composites. For the stripping soil content ranged from 30% and 60%, for the dredging material contents ranged from 20% and 50% and binder common quicklime content ranged from 15% to 30%. Were molded curing ages of 3 days, 7, 14, 28, 60, 90, 180 and 365 days. The increase in compressive strength during curing was derived from the chemical reactions of solid particles of raw materials in alkaline environment generating the new amorphous formations. Also the raw materials were analyzed in the SEM with EDS method, DRX and FRX, to obtain the chemical composition and formation structures of the new composite. All results of the uniaxial compressive strength, with 28 days of curing the environment of the twelve (12) compositions, obtained average results of 7.7 MPa, satisfactorily meeting the NBR 7170:1983 standard that determines the resistance to compression equal or above 4.0 MPa, for the production of building materials for sealing masonry without structural purposes. Proving the use of these composites in construction materials, especially for thread block or brick fences without structural purposes, without the need for cooking or heating energy project for the healing of parts, contributing to the environment and sustainability Environmental.
288

Material para construção civil a partir de lodo de estação de tratamento de água, lama de polimento de mármore e resíduo de produção de cal / Construction material from water treatment sludge, marble polish mud and lime production waste

Hackbart, Fernanda Meireles 11 December 2015 (has links)
O crescimento populacional acelerado é o grande motivador para o desenvolvimento do setor da construção civil e o aumento na demanda por água potável, tendo como consequência, um aumento gradativo na geração de resíduos sólidos. Dessa forma, este trabalho foi realizado com o intuito de reciclar resíduos industriais e municipais incorporando-os em materiais para a construção civil. O compósito produzido a partir de lodo de estação de tratamento de água e lama de polimento de mármore, aplicando resíduo de produção de cal como ligante, foi avaliado quanto ao seu desempenho mecânico e sua estrutura morfológica. As matérias-primas foram caracterizadas quanto sua composição química, mineralógica,morfológica, granulométrica e, também, o teor de umidade. Com os materiais caracterizados, foram desenvolvidas nove composições variando-se o teor de lodo de estação de tratamento de água entre 25 e 50%, o teor de lama de polimento de mármore entre 35 e 50% e o resíduo de produção de cal entre 10 e 30%. Os compósitos foram submetidos a ensaios de resistência mecânica, absorção de água, análise química, mineralógica e morfológica. Os materiais desenvolvidos apresentaram, no 3° dia de cura, valor de resistência mecânica máxima de 4,65 MPa, no 7° dia 6,36 MPa, no 14° dia 6,74 MPa, no 28° dia 5,98 MPa, no 60° dia 8,52 MPa, no 90° dia 11,75 MPa e no 180° dia 12,06 MPa. Os valores de absorção de água aos 28 dias de cura variaram de 16,27 a 26,32% e aos 90 dias, de 13,57 a 23,56%. / The rapid population growth is the great motivator for the development of the construction industry and the increased demand for drinking water, resulting in a gradual increase in the generation of solid waste. Thus, this work was carried out in order to recycle industrial and municipal wastes incorporating them into materials for civil construction. The composite produced from water treatment sludge and marble polishing mud, applying lime production waste as a binder, was evaluated for its mechanical performance and its morphological structure. The raw materials were characterized for their chemical composition, mineralogy, morphology, particle size and also the moisture content. With the featured materials nine compositions have been developed varying the content of the water treatment sludge between 25 to 50%, marble polishing mud between 35 to 50% and the lime production waste between 10 to 30%. The composites were subjected to mechanical strength tests, water absorption, chemical and mineralogical composition and morphology. The developed materials presented, on the 3rd day of hydration, maximum strength value of 4.65 MPa, the 7th day 6.36 MPa, on the 14th day 6.74 MPa, the 28th day 5.98 MPa, on the 60th day 8.52 MPa at 90th day 11.75 MPa and 180th day 12.06 MPa. The water absorption values after 28 days of hydration ranged from 16.27% to 26.32% and after 90 days, from 13.57% to 23.56%.
289

Projekt přípravy a realizace výrobní a skladovací haly v Mniší / Execution of Production and Storage Hall in Mniší

Šilhová, Kristýna January 2018 (has links)
The diploma thesis deals with the realization of a production and storage hall for the engineering industry. Part of the realization of the production hall is the demolition work of the existing agricultural building. The reconstruction of the existing premises of locksmith's workshop and dressing room for employees is also being implemented. For the preparation of this project, the thesis deals with the implementation of the main technological stages, technological plans for demolition work and substructure, transport routes of the main building materials and machines, technical report of the building site, time and financial plan of the construction, security measures especially for demolition works, quality control when drilling a pilot.
290

Towards higher predictability in enzyme engineering : investigation of protein epistasis in dynamic ß-lactamases and Cal-A lipase

Alejaldre Ripalda, Lorea 12 1900 (has links)
L'ingénierie enzymatique est un outil très avantageux dans l'industrie biotechnologique. Elle permet d'adapter les enzymes à une activité ou à une condition de réaction spécifique. En outre, elle peut permettre de déchiffrer les éléments clés qui ont facilité leur modification. Bien que l'ingénierie enzymatique soit largement pratiquée, elle comporte encore plusieurs goulets d'étranglement. Certains de ces goulets d'étranglement sont techniques, comme le développement de méthodologies pour la création de banques de mutations ciblées ou la réalisation de criblages à haut débit, et d'autres sont conceptuels, comme le déchiffrage des caractéristiques clés pertinentes d'une protéine cible pour la réussite d'un projet d'ingénierie. Parmi ces défis, l'épistasie intra-génique, ou la non-additivité des effets phénotypiques des mutations, est une caractéristique qui entrave grandement la prévisibilité. L'amélioration de l'ingénierie enzymatique nécessite une approche multidisciplinaire qui inclut une meilleure compréhension des relations structure-fonction-évolution. Cette thèse vise à contribuer à l'avancement de l'ingénierie enzymatique en étudiant deux systèmes modèles. Premièrement, des variantes dynamiques de la ß-lactamase TEM-1 ont été choisies pour étudier le lien entre la dynamique des protéines et l'évolution. La ß-lactamase TEM-1 a été largement caractérisée dans la littérature, ce qui s'est traduit par des connaissances approfondies sur son mécanisme de réaction, ses caractéristiques structurelles et son évolution. Les variantes de la ß-lactamase TEM-1 utilisées comme système modèle dans cette thèse ont été largement caractérisées, montrant une dynamique accrue à l'échelle temporelle pertinente pour la catalyse (µs à ms) mais maintenant la reconnaissance du substrat. Dans cette thèse, l'évolution in vitro de ces variantes dynamiques a été réalisée par des cycles itératifs de mutagenèse et de sélection aléatoires pour permettre une exploration impartiale du paysage de ‘fitness’. Nous démontrons que la présence de ces mouvements particuliers au début de l'évolution a permis d'accéder à des voies de mutations connues. De plus, des interactions épistatiques connues ont été introduites dans les variantes dynamiques. Leur caractérisation in silico et cinétique a révélé que les mouvements supplémentaires sur l'échelle de temps de la catalyse ont permis d'accéder à des conformations conduisant à une fonction améliorée, comme dans le TEM-1 natif. Dans l'ensemble, nous démontrons que l'évolution de la b-lactamase TEM-1 vers une nouvelle fonction est compatible avec divers mouvements à l'échelle de temps µs à ms. Il reste à savoir si cela peut se traduire par d'autres enzymes ayant un potentiel biotechnologique. Deuxièmement, la lipase Cal-A, pertinente sur le plan industriel, a été choisie pour identifier les caractéristiques qui pourraient faciliter son ingénierie. La lipase Cal-A présente des caractéristiques telles que la polyvalence du substrat et une grande stabilité thermique et réactivité qui la rendent attrayante pour la modification des triglycérides ou la synthèse de molécules pertinentes dans les industries alimentaire et pharmaceutique. Contrairement à TEM-1, la plupart des études d'évolution in vitro de la lipase Cal-A ont été réalisées dans un but industriel, avec une exploration limitée de l'espace de mutation. Par conséquent, les caractéristiques qui définissent la fonction de la lipase Cal-A restent insaisissables. Dans cette thèse, nous faisons état de la mutagenèse ciblée de la lipase Cal-A, confirmant l'existence d'une région clé pour la reconnaissance du substrat. Cela a été fait en combinant une nouvelle méthodologie de création de bibliothèque basée sur l'assemblage Golden-gate avec une visualisation structurelle basée sur des scripts pour identifier et cartographier les mutations sélectionnées dans la structure 3D. La caractérisation et la déconvolution de deux des plus aptes ont révélé l'existence d'une épistasie dans l'évolution de la lipase Cal-A vers une nouvelle fonction. Dans l'ensemble, nous démontrons que l’identification d'une variété de propriétés suite à la mutagenèse ciblée peut grandement améliorer la connaissance d'une enzyme. Cette information peut être appliquée pour améliorer l'efficacité de l'ingénierie dirigée. / Enzyme engineering is a tool with great utility in the biotechnological industry. It allows to tailor enzymes to a specific activity or reaction condition. In addition, it can allow to decipher key elements that facilitated their modification. While enzyme engineering is extensively practised, it still entails several bottlenecks. Some of these bottlenecks are technical such as the development of methodologies for creating targeted mutational libraries or performing high-throughput screening and some are conceptual such as deciphering the key relevant features in a target protein for a successful engineering project. Among these challenges, intragenic epistasis, or the non-additivity of the phenotypic effects of mutations, is a feature that greatly hinders predictability. Improving enzyme engineering needs a multidisciplinary approach that includes gaining a better understanding of structure-function-evolution relations. This thesis seeks to contribute in the advancement of enzyme engineering by investigating two model systems. First, dynamic variants of TEM-1 ß-lactamase were chosen to investigate the link between protein dynamics and evolution. TEM-1 ß-lactamase has been extensively characterized in the literature, which has translated into extensive knowledge on its reaction mechanism, structural features and evolution. The variants of TEM-1 ß-lactamase used as model system in this thesis had been extensively characterized, showing increased dynamics at the timescale relevant to catalysis (µs to ms) but maintaining substrate recognition. In this thesis, in vitro evolution of these dynamic variants was done by iterative rounds of random mutagenesis and selection to allow an unbiased exploration of the fitness landscape. We demonstrate that the presence of these particular motions at the outset of evolution allowed access to known mutational pathways. In addition, known epistatic interactions were introduced in the dynamic variants. Their in silico and kinetic characterization revealed that the additional motions on the timescale of catalysis allowed access to conformations leading to enhanced function, as in native TEM-1. Overall, we demonstrate that the evolution of TEM-1 b-lactamase toward new function is compatible with diverse motions at the µs to ms timescale. Whether this can be translated to other enzymes with biotechnological potential remains to be explored. Secondly, the industrially relevant Cal-A lipase was chosen to identify features that could facilitate its engineering. Cal-A lipase presents characteristics such as substrate versatility and high thermal stability and reactivity that make it attractive for modification of triglycerides or synthesis of relevant molecules in the food and pharmaceutical industries. Contrary to TEM-1, most in vitro evolution studies of Cal-A lipase have been done towards an industrially-specified goal, with limited exploration of mutational space. As a result, features that define function in Cal-A lipase remain elusive. In this thesis, we report on focused mutagenesis of Cal-A lipase, confirming the existence of a key region for substrate recognition. This was done by combining a novel library creation methodology based on Golden-gate assembly with script-based structural visualization to identify and map the selected mutations into the 3D structure. The characterization and deconvolution of two of the fittest revealed the existence of epistasis in the evolution of Cal-A lipase towards new function. Overall, we demonstrate that mapping a variety of properties following mutagenesis targeted to specific regions can greatly improve knowledge of an enzyme that can be applied to improve the efficiency of directed engineering.

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