Tuberculosis, caused by Mycobacterium tuberculosis, still poses a huge global health threat today. During infection, the bacilli are believed to confront with various stresses, including hypoxia. Hypoxia is known to trigger the bacteria to adapt into a nonreplicating dormant state associated with reduced drug susceptibility. In addition to dormancy, mycobacteria, like other bacteria, may switch to sessile biofilm growth that is generally associated with augmented drug and stress tolerance. Bacterial biofilm is physically heterogeneous and may harbor cells displaying distinct metabolic activities. It is therefore likely that some cell populations within an established biofilm are in a nonreplicating dormant state. A better understanding of mycobacterial dormancy establishment and biofilm growth could unveil crucial bacillary survival strategies that will provide insights into a rational design of chemotherapy regimen.The mycobacterial chaperonin 60.1 (Cpn60.1, also known as GroEL1), a probable chaperonin and/or nucleoid associated protein, is necessary for mycobacterial cell wall virulence lipid biosynthesis, which was reported to be enhanced at the early stage of mycobacterial hypoxic adaptation, and for reduced drug susceptibility under aerobic condition. We therefore investigated whether Cpn60.1 was essential for mycobacterial adaptation to hypoxic dormancy using Mycobacterium bovis BCG as the model organism. We found that Cpn60.1, although nonessential for mycobacterial survival, reduced isoniazid (INH) susceptibility under hypoxia. Unexpectedly and interestingly, INH’s bactericidal activity was found to involve electron transport chain perturbation (e.g. enhanced oxygen consumption and increased adenosine triphosphate level) via NADH dehydrogenases, succinate dehydrogenases, cytochrome bc1 and F0F1 ATP synthase. Moreover, respiratory reprogramming to cytochrome bd was observed to protect against INH-induced killing.Intriguingly, we found that Cpn60.1 was required for respiratory and energetic downregulation under excess glycerol as well as in response to drugs (such as Q203 inhibiting cytochrome bc1). Cpn60.1 also played a role in lipidomic adaptation under excess glycerol (e.g. enhanced phthiocerol dimycocerosate and glycerol-based lipids synthesis but repressed trehalose-based lipids synthesis). Defective energetic downregulation in the absence of Cpn60.1 compromised the establishment of the Crabtree effect characterized by respiratory downregulation, glycolytic enhancement and secretion of several metabolites (i.e. pyruvate, succinate, acetate and glutamate). The Crabtree effect was necessary for mycobacterial adaptation to excess glycerol and biofilm growth. Due to a compromised Crabtree effect, a Cpn60.1-deficient Mycobacterium bovis BCG strain, i.e. the Δcpn60.1 strain, suffered from methylglyoxal-induced growth stasis under excess glycerol, leading to the biofilm defect under the standard biofilm medium. Given the essentiality for Cpn60.1 in mycobacterial respiratory adaptation under stresses, it is likely that the enhanced INH susceptibility of the Δcpn60.1 strain under hypoxia was due to a problematic respiratory reprogramming.In summary, Mycobacterium bovis BCG Cpn60.1 is not required for bacillary survival under hypoxic dormancy. However, it participates in various adaptations (e.g. respiratory downregulation) necessary for mycobacterial biofilm growth and for escaping INH’s bactericidal mechanism. / Doctorat en Sciences biomédicales et pharmaceutiques (Pharmacie) / info:eu-repo/semantics/nonPublished

Face au problème des micropolluants émergents trouvés dans l’eau, l’utilisation de carbones activés est un moyen de réduire cette pollution à la source. Le but de ce travail est de mieux comprendre les mécanismes d’adsorption de certains micropolluants sur des tissus et feutres de carbones activés.Neuf molécules ont été étudiées dont des médicaments : la carbamazépine (CBZ), le diclofénac (DFN), l’ibuprofène (IBP) et l’ofloxacine (OFX), un produit anticorrosion : le benzotriazole (BZT), un perturbateur endocrinien : le bisphénol-A (BPA), deux herbicides : le mécoprop (MCP) et le pentachlorophénol (PCP) et une molécule utilisée comme indicateur de pollution des eaux usées : la caféine (CAF). Les adsorbants ultramicroporeux (tissu KIP1200 et feutre CSV4) et l’adsorbant mésoporeux (tissu BBV 800) (fournis par Dacarb, France) ont été caractérisés par adsorption d'azote à 77K et de CO2 à 273K, titrages acido-basiques (méthode de Boehm), mesure du pHpzc (point isoélectrique). Les cinétiques et isothermes d'adsorption ont été étudiées à 25°C à pH=7,5 dans un tampon phosphate NaHPO4/KH2PO4 (à 0,04M). La concentration résiduelle est analysée par HPLC.Les cinétiques d'adsorption ont été étudiées pour les 9 molécules à différentes concentrations initiales. Le temps pour atteindre l’équilibre d’adsorption dépend du volume des molécules ainsi que de leur affinité avec l’adsorbant. La quantité maximale adsorbable dépend du volume microporeux ainsi que de la surface spécifique de l’adsorbant, la quantité adsorbable est donc plus importante sur le tissu KIP 1200 que sur le feutre CSV 4. La vitesse de diffusion est la plus lente pour les adsorbants possédant un volume microporeux important, le tissu mésoporeux BBV 800 permet donc une adsorption rapide grâce à de plus larges pores qui permettent un accès plus rapide à la porosité.Des analyses en mélanges binaires et multi composés ont alors été réalisées pour connaître les paramètres clés gouvernant les cinétiques d’adsorption. Une compétition existe entre molécules dans certains cas (BZT et MCP par exemple) avec une première phase gouvernée par la cinétique d’adsorption liée à la diffusion dans les pores et la deuxième phase gouvernée par des phénomènes thermodynamiques entre le système soluté/solvant/carbone.Les isothermes d'adsorption ont été réalisés à 3 températures différentes et modélisées par des équations de Langmuir-Freundlich pour tous les micropolluants. Des paramètres thermodynamiques (enthalpie d’adsorption et enthalpie libre) ont alors été calculés et corrélés aux propriétés physico-chimiques des molécules. Une corrélation est mise en évidence entre l’enthalpie libre et la polarisabilité des molécules ainsi que les forces de Van der Waals déterminées avec le logiciel COSMO-RS mettant en évidence l’importance des forces non polaires dans le phénomène d’adsorption. Des mesures par calorimétrie d’adsorption à très faibles quantités adsorbées ont permis de mettre en évidence que l’entropie est le paramètre thermodynamique qui contrôle l’adsorption de molécules (BZT, PCP, CAF et OFX) sur le tissu KIP 1200. De fortes énergies d’interaction ont été mis en évidence entre les molécules (BZT, CAF et OFX) et les sites d’adsorption.Une étude d’adsorption-désorption de N2 et de CO2 sur des tissus KIP 1200 chargés en PCP, BZT, CAF et OFX a permis de mieux localiser le lieu de l’adsorption dans la porosité montrant une adsorption prioritairement dans les ultramicropores puis dans les supermicropores. Il a été montré également par cette méthode et par des mesures thermiques que l’eau est fortement adsorbée dans la porosité. / A lot of studies have revealed that some organic molecules such as pharmaceutical molecules, solvents, pesticides, etc.. are frequently found in water, at concentrations below µg/L, even after treatment at the exhaust of wastewater treatment plants. These molecules are highly toxic when accumulated in environment. One of the possibility for removing these micropollutants is the adsorption on activated carbons. Thus the aim of this work is to better understand the adsorption mechanism of some micropollutants onto activated carbon (ACs) in felt or fabric form.Nine micropollutants were studied, such as some pharmaceuticals: Carbamazepine (CBZ), Diclofenac (DFN), Ibuprofen (IBP), and Ofloxacin (OFX); one anti-corrosion compound : Benzotriazol (BZT); two herbicides : Mecoprop (MCP) and Pentachlorophenol (PCP) and an endocrine disruptor : Bisphenol A (BPA). Adsorption of Caffeine (CAF) which is an anthropic indicator of pollution in waste water, was also studied. The ACs (microporous KIP1200 fabric and CSV4 felt and mesoporous BBV 800 fabric, from Dacarb, France) were characterized by N2 adsorption-desorption at 77 K and CO2 adsorption at 273 K, pHpzc (point of zero charge) measurements and acido-basic titrations (Boehm method). The adsorption kinetics and isotherms were studied at pH 7.4 at 25°C in NaHPO4/KH2PO4 buffered solutions (about 0.04 M) using UV spectrometry and HPLC for the analysis of organic molecules in the remaining solution.Kinetics have been studied for 9 molecules at different initial concentrations. Time to reach adsorption equilibrium depends of the volume of the molecule and its affinity with the activated carbon. The maximum adsorbed quantity depends of the microporous volume and the specific area of the adsorbent, the adsorbed quantity is then bigger for KIP 1200 fabric than for CSV 4 felt. The speed of diffusion is slower for the adsorbent with high microporous volume, the mesoporous BBV 800 fabric gives place to a quick adsorption kinetics thanks to its large pores that gives an easy access to porosity.Binary and multi components kinetics have been done in order to understand key processes that drive kinetics adsorption. Competition between molecules have been shown (for BZT and MCP for example). Adsorption kinetics can be divided into two phases: the first one is driven by pore diffusion and the second one by thermodynamic phenomenon between the solute, the solvent and the AC.The adsorption isotherms of the molecules were studied at 13, 25 and 40°C; and the thermodynamic parameters (isoteric enthalpies and entropies Gibbs free energies) were determined. A correlation between Gibbs free energy and polarizability of molecules as well as Van der Waals energy calculated with Cosmotherm software shows the importance of non polar forces on adsorption phenomenon. Adsorption calorimetry experiments showed that entropy is the thermodynamic parameter that drives adsorption of molecules (BZT, PCP, CAF and OFX) onto KIP 1200 fabric.The pore size distributions of the carbons loaded with micropollutants were determined by DFT simulation from CO2 and N2 adsorption isotherms, to investigate the porosity accessible to the adsorbate. The accessible pore are firstly the ultramicropores and then supermicropores. With this technique and thermal experiments, it has been shown that water is highly bonded inside the porosity.

Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro de Ciências Jurídicas. Programa de Pós-Graduação em Direito / Made available in DSpace on 2012-10-23T23:08:06Z (GMT). No. of bitstreams: 1 251763.pdf: 32462871 bytes, checksum: 35e3e51ed98eeb11eff49ae44aa81925 (MD5)

Growing concerns of the negative effects on the environment and dependency of fossil fuelsare major driving forces for finding novel sustainable production pathways for plastic.Metabolic engineering has emerged as a powerful tool to enable microorganisms to producenon-native metabolites. The aim of this project was recombinant production of 4-hydroxybutyrate (4-HB) by expressing two enzymes in the model organism Escherichia coli.α-ketoglutarate decarboxylase (SucA) from Mycobacterium smegmatis followed by 4-hydroxybutyrate dehydrogenase (4-HBd) from Clostridium kluyveri was expressed inEscherichia coli. Results showed that the genes were successfully transformed and expressedin E. coli and after protein purification a concentration of 0.9 g/L SucA and 9.8 g/L 4-HBdwas achieved. Furthermore, some protein activity was detected by a coupled reaction withSucA and 4-HBd. When the enzymes got coupled together a change in NADH concentrationcould be detected spectrophotometrically. The enzymes were also tested for substratespecificity by using substrates with various carbon chain lengths and a decrease in NADHconcentration was seen. However, a decrease in the negative control for the experiments wasalso seen indicating a breakdown of NADH over time rather than consumption. Therefore, noconclusion could be drawn about the promiscuity of the enzymes. Lastly a single plasmidssystem was tested where both the genes were ligated on the same plasmid (pCDF duet) andexpressed successfully in E. coli Bl21DE3. / Ökad oro för miljön samt behovet av fossila resurser för produktion av plaster har gjort detnödvändigt att skapa nya och mer hållbara produktions vägar. Genetisk modifikation av olikaorganismer har utvecklats som ett starkt redskap för att få mikroorganismer att framställametaboliter som de normalt inte producerar. Målet med detta projekt var rekombinantproduktion av gamma hydroxibutansyra (4-HB) genom att uttrycka två enzym i modellorganismen Escherichia coli. Dessa enzym bestod av α-ketoglutarat dekarboxylas (SucA) frånMycobacterium smegmatis samt 4-hydroxybutyrate dehydrogenas (4-HBd) från Clostridiumkluyveri. Resultaten visade att proteinerna lyckades utryckas i E. coli med en koncentration av0,9 g/L SucA och 9,8 g/L 4-HBd som uppnåddes efter rening. Utöver detta detekterades ävenviss enzymaktivitet genom att kopplad enzymreaktion mellan 4-HBd och SucA och mätakonsumtionen av NADH spektrofotometriskt över tid. Enzymen testades även försubstratspecificitet genom att köra reaktionen med substrat med olika längd på kolkedjan. Dåkunde en minskning i NADH koncentrationen ses men det gjordes det även för de negativakontrollerna vilket indikerar nedbrytning av NADH och inte konsumtion av NADH. Ingaslutsatser angående enzymens substratspecificitet kunde därför dras. Det sista som gjordes varatt sätta in båda generna i ett en plasmidsystem där båda generna sattes in på samma plasmid(pCDF duet) och uttrycktes framgångsrikt i E. coli Bl21DE3.

Syfte: I den komplexa miljö som inköp inom lågvolymstillverkande företag befinner sig i ställs krav på kostnadsreducering. Ofta är fokus på inköpspriset medan flertalet osynliga kostnader, som ofta är större, är dolda under vattenytan. Det återfinns befintlig teori kring totalkostnadsanalyser men det finns fortfarande behov av att skapa möjlighet för praktisk implementering på företag. I linje med det är studiens syfte att utveckla en praktisk totalkostnadsanalysprocess för inköp inom lågvolymstillverkande företag. För att uppnå syftet har tre frågeställningar formulerats enligt följande: (1) Vilka kostnader återfinns vid inköp av artiklar inom lågvolymstillverkning? (2) Hur bör kostnaderna vid inköp av artiklar inom lågvolymstillverkande företag prioriteras i en totalkostnadsanalys? (3) Hur bör kostnaderna vid inköp av artiklar inom lågvolymstillverkande företag beaktas vid en totalkostnadsanalys? Metod: Studien baseras på en fallstudie av kvalitativ karaktär. Studien genomfördes på Saab Aeronautics i Linköping, där empiri insamlats via datainsamlingsteknikerna dokumentstudie, enkät och intervju. Därtill utfördes en litteraturgenomgång där befintlig teori inom området kartlades. Vidare jämfördes teori och empiri från företaget för att fastställa den praktiska process som var syftet med studien att uppnå. Resultat: I studien identifieras 14 grupper av kostnader som sedan storleksmässigt delas upp efter artikeltyp och prioriterades baserat på empiri från fallföretaget. Vidareresulterar studien i hur artiklar beaktas utifrån teori om Kraljics matris och leverantörspreferensiering samt empiri om hur olika artiklar kan hanteras utifrån empiri från fallföretaget. Studien resulterar i en totalkostnadsanalysprocess i åtta steg där praktisk möjlighet till implementering skapas via artikeluppdelning. Ekonomisk och miljömässig hållbarhet uppnås genom att företag ges möjligheten att minska sina kostnader och göra miljövänligare beslut. Implikationer: Studien bidrar till både praktiska och teoretiska implikationer.Processen är ett verktyg som inköpsavdelningen på lågvolymstillverkande företag kan använda sig av för att skapa sig en möjlighet att få vetskap om dolda kostnader.Vetskapen om kostnaderna skapar även möjlighet till att minska kostnader utifrån ett totalkostnadsperspektiv. I arbetet skapas en praktisk process utifrån de två redan befintliga litteraturområden, totalkostnad och artikeluppdelning. Därtill skapas bidrag till forskningen om möjligheten att kombinera dessa teoretiska områden. Avgränsningar: Studien är begränsad till ett företag via enfallstudie. Därtill sker utgångspunkt ifrån inköpsavdelningen och begränsas studien till att endast undersöka kvalitativa delar av en totalkostnadsanalysprocess, det vill säga inte genomförande av beräkningar.

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Der Citratzyklus (TCA) ist einer der bedeutendsten Stoffwechselwege für alle lebenden Organismen. Trotz der zentralen Rolle dieses Prozesses im Pflanzenmetabolismus ist er nur relativ wenig untersucht worden. In dieser Arbeit berichte ich über die Produktion und die funktionale Analyse von Tomatenpflanzen (Solanum lycopersicum), die unabhängig eine leicht eingeschränkte Aktivität der mitochondrialen Citrat-Synthase (CS) und zweier Isocitrat-dehydrogenasen (mitochondriale NAD-IDH und cytosolische NADP-ICDH) zeigen. Die transgene Pflanzen wiesen mehrheitlich keine erkennbare Veränderung eines Wachstumphänotyps auf. Obwohl die photosyntetische Leistung keine Änderungen gezeigt hatte, war die mitochondriale Respiration gestiegen, begleitet von einem reduzierten Kohlenstoff-fluss durch den Citratzyklus. Darüber hinaus waren die CS Pflanzen charakterisiert durch wesentliche Änderungen im Blattmetabolismus, einschließlich eines eingeschränkten Niveaus des photosynthetischen Pigments und Zwischenprodukten des Citratzyklus zusammen mit einer Akkumulation von Nitraten, verschiedenen Aminosäuren und Stärken. Zusammengefasst deuten diese Ergebnisse auf eine Einschränkung der Nitrat-Aufnahme hin. Das mit Hilfe von TOM1 Mikroarrays und quantitativer RT-PCR durchgeführte Transcript-profiling hat gezeigt, dass die fehlende Aktivität der mitochondrialen CS teilweise von einer gestiegenen, peroxisomalen CS Isoform ausgeglichen wird. Die metabolische Verschiebung ergab eine Verstärkung der photorespiratorischen Leistung, die vermutlich eine ausgleichende Rolle in der Produktion organischer Säuren und der Wiederherstellung der Redox-Balance spielt. Interessantenweise war die metabolische Antwort von Blättern auf Stickstoffmangel in NADP-ICDH Pflanzen dramatischer als in NAD-IDH Pflanzen, was darauf hindeutet, dass die cytosolische Isoform der Hauptlieferant von 2-Oxoglutarat im Tomatenmetabolismus sein könnte. / Although the TCA cycle is a respiratory metabolic pathway of central importance for all living organisms, relatively few molecular physiological studies of plants were performed to date. Here, I report the generation and functional analysis of tomato plants (Solanum lycopersicum) independently displaying mildly limited activity of mitochondrial citrate synthase (CS) and two isocitrate dehydrogenases, namely mitochondrial NAD-IDH and cytosolic NADP-ICDH. The transgenic plants revealed minor phenotypic alterations. Although the leaf photosynthetic performance was largely unaltered, the changes in mitochondrial respiration and carbon flux through the TCA cycle were observed. Moreover, the plants were characterized by significant modifications in the leaf metabolic content and in maximal catalytic activities of several enzymes involved in primary C and N metabolism. These results hint towards limitations in nitrate assimilation pathway. The transcript profiling performed by utilizing TOM1 microarrays and quantitative RT-PCR approach revealed that the deficiency in mitochondrial CS activity was partially compensated by up-regulation of peroxisomal CS isoform. The limitations in the activities of isocitrate dehydrogenases resulted in up-regulation of the photorespiratory pathway, which presumably played a compensatory role in supporting organic acid production and re-establishing redox balance in the transgenic leaves. Interestingly, the leaf metabolic response towards nitrogen starvation conditions was far more dramatic in NADP-ICDH transgenic plants than NAD-IDH plants, hinting that the cytosolic isoform may be the major 2-oxoglutarate supplier in tomato metabolism.

Submitted by Filipe dos Santos (fsantos@pucsp.br) on 2018-06-14T12:37:22Z No. of bitstreams: 1 Isabel Cristina de Brito Franco Afonso.pdf: 2704361 bytes, checksum: 4d00cd2acdeacef7c19cfd9a912353f9 (MD5) / Made available in DSpace on 2018-06-14T12:37:22Z (GMT). No. of bitstreams: 1 Isabel Cristina de Brito Franco Afonso.pdf: 2704361 bytes, checksum: 4d00cd2acdeacef7c19cfd9a912353f9 (MD5) Previous issue date: 2018-03-13 / Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / This research is associated to the Program of Graduate Studies in Education: Curriculum of the Pontifical Catholic University of São Paulo and is part of the Research Line of New Technologies in Education. It aims to show ways of implementation the Authorial Cycle foreseen in the Program of Curricular and Administrative Reorganization, Expansion and Strengthening of the Municipal Education System of São Paulo (2013), experienced by the teachers in the development of Collaborative Authorial Projects (CAP) with the 9th grade students. Methodologically, the research is qualitative in terms of Bogdan and Biklen, (2010) in the context of an ethnographic case study André (2005). The participant observation approach was adopted, and the data collection was used in the field data collection, semi-structured interviews with teachers and school coordinator, focus group with the students and documentary research in the Pedagogical Political Project of the School. The narrative analysis of the data under the Angrosino (2009) assumption, pointed to a conjunction of aspects that contributed to the curriculum experienced in the researched school approaching the objectives prescribed in the official documents: the role of teachers as mediators of the curriculum, the alignment of the Pedagogical Political Project of the School and the Municipal Education System of São Paulo educational project, the performance of the Pedagogical Coordinator as a transforming agent in the school, student engagement in developing the CPA and community involvement in the development and presentation of CPA. Although, the objective of this research is not to create generalizations, but to describe the process of implantation of the experienced by the researched school, the aspects synthesized here, can point out ways for the implantation of CPA projects in other schools or even, different projects and policies. New research will expand these results and analyze a greater number of schools seeking to identify highlights that contribute to the implantation of public policies in the school / Esta pesquisa está vinculada ao Programa de Pós-Graduação em Educação: Currículo, da Pontifícia Universidade Católica de São Paulo e se insere na Linha de Pesquisa Novas Tecnologias na Educação. Objetiva apontar caminhos sobre o processo de implantação do Ciclo Autoral, previsto no Programa de Reorganização Curricular e Administrativa, Ampliação e Fortalecimento da Rede Municipal de Ensino de São Paulo (2013), vivenciado pelos professores no desenvolvimento dos Trabalhos Colaborativos de Autoria (TCA) dos alunos do 9º ano de uma escola da rede. Metodologicamente a pesquisa é de cunho qualitativo pautado em Bogdan e Biklen, (2010), nos contornos de um estudo de caso etnográfico de André (2005). Adotou-se o enfoque da observação participante e foram utilizados na coleta de dados observação com registros em caderno de campo, entrevistas semiestruturadas com os professores orientadores de TCA e professora coordenadora, grupo focal com os alunos e pesquisa documental no Projeto Político Pedagógico da Escola para complementação das informações. A análise narrativa dos dados sob o pressuposto de Angrosino (2009) apontou para uma conjunção de aspectos que contribuíram para que o currículo vivenciado na escola Jardim se aproximasse aos objetivos prescritos nos documentos oficiais da proposta do Ciclo Autoral: o papel dos professores como mediadores do currículo, o alinhamento do PPP da escola e o projeto educacional da SME, a atuação da gestão, caracterizado pela atuação da Coordenadora Pedagógica como agente transformadora da e na escola, o engajamento dos estudante em desenvolver os TCA e o envolvimento da comunidade no desenvolvimento e apresentação dos TCA. Embora, compreenda-se que o objetivo desta pesquisa não é criar generalizações, mas sim, descrever o processo de implantação do TCA vivenciado pela escola Jardim, os aspectos aqui sintetizados podem apontar caminhos para a implantação de projetos de TCA em outras escolas ou mesmo, diferentes projetos e políticas. Novas pesquisas poderão ampliar este olhar e analisar um maior número de escolas buscando identificar as identidades ou destaques que contribuam com a implantação de políticas públicas no dia a dia da escola

La maîtrise accrue des matériaux et des procédés de forgeage permet aujourd'hui d'obtenir des engrenages coniques d'une qualité suffisante pour pouvoir les utiliser sans autre procédé de finition. Ce sont les pièces dites «net shape». Grâce à cette évolution technologique, il est nécessaire de d'optimiser la définition géométrique de ces engrenages en tenant compte des possibilités des procédés de forgeage, en particulier. Tout d'abord, la définition de la géométrie nominale des engrenages coniques à denture droite basée sur les propriétés géométriques et cinématiques du profil en développante de cercle sphérique est réétudiée et a abouti à une modélisation paramétrique des surfaces actives en intégrant un bombé longitudinal. Afin de garantir un certain niveau de qualité de l'engrènement, il est nécessaire de limiter les variations inhérentes au procédé de forgeage et aux ressources de fabrication, il s'agit de l'analyse et de la synthèse des tolérances. Cette analyse a nécessité une modélisation géométrique des engrenages incluant les écarts intrinsèques et les écarts de situation. L'analyse de l'impact de ces écarts sur l'erreur cinématique (Tooth Contact Analysis) repose sur la résolution d'un système d'équations non linéaires pour chaque position du pignon et d'un traitement de ces résultats; la difficulté de cette analyse est la grande sensibilité des résultats aux écarts. Cet outil «TCA» est le module principal de l'analyse des tolérances qui est réalisée de façon statistique par simulation de Monte Carlo. L'analyse des tolérances permet de valider une solution d'allocation de celles-ci mais ne permet pas son allocation automatique. Ainsi une approche de synthèse des tolérances a été validée, il s'agit de l'optimisation par algorithme génétique où la fonction objectif est de minimiser le ratio coût des tolérances sur la probabilité de respect des exigences. Cette analyse et cette synthèse ont été menées dans un premier temps sans charge, en considérant l'engrenage comme indéformable. Puis, la prise en compte des déformations est réalisée par la méthode des coefficients d'influences. Le problème de contact et de déformation globale de la denture sont découplés. Les coefficients d'influences de contact sont estimés par la méthode de Boussinesq et Cerruti. Les coefficients d'influence de flexion sont estimés par interpolation et méthode des éléments finis. Ce modèle permet l'analyse de l'engrènement sous charge mais les temps de calculs restent un handicap pour l'analyse des tolérances. Ces modèles de comportement pourront être affinés dans de futurs travaux et être le support de nouveaux modèles de spécification des engrenages, de suivi du processus de fabrication, d'une meilleure connaissance des interactions géométrie-mécanique-matériau, etc.

Construction is one of the oldest of industries in the world, with the first establishedconstruction company being established around 230 BC. One of the biggest industries inEurope, at an estimated €900 billion a year, it also accounts for 40% of total energy consumption and 40% of total waste generation in the EU1 . Although the majority ofthese are from the use phase of the built environment, there is a lack of a comprehensiveenvironmental risk management system for the construction phase. This study proposesan environmental risk management framework based on the Beer-Ziolkowski model of risk management for both site specific and non-site specific construction operations witha stakeholder centric approach. It proposes stakeholder involvement to identify the risksaided with trend analysis of strategic regulatory implications from the concernedauthority - Norwegian Ministry of Local Government and Regional Development and thecurrent orgnisational practice of objective environmental risk identification from ISO14001 guidance. Scope of site specific and non-site specific risks are narrowed down tosite operational setup and construction materials respectively, consistent with theorganisations view of the most important risks from those two classes of risks. Riskassessment is suggested through Fault Tree Analysis (FTA) method for site specific risksand European Union System for the Evaluation of Substances (EUSES) for non-sitespecific risks. Total Cost Accounting (TCA) of project alternative evaluation isrecommended with a view to internalise the external costs. A two tiered integration ofrisk information in the buisess process is suggested – categorised risk reduction processat the level of projects and general good practice aided with risk information at the policylevel. Being a framework for management of environmental risk as opposed to a methodfor a specific environmental risk, the principles and suggestions are broadly scoped withcase studies for identification and analysis of risks.Through the practice of prudent engagement of stakeholders and scientific risk assessments, this framework would help the organisation enable safer operational practices in the context of environmental effects. In foresight this in turn will have rendered the host firm more competent in terms of making sustainable business decisions. / Byggindustrin är en av de äldsta industrierna i världen. Det första företaget etabeleradesca 230 BC. Byggindustrin är även en av de största industrierna i Europa med €900miljarder i omsättning varje år, men ansvarar även för ungefar 40% av energiförbrukningen och 40% utav den totalla avfallsgeneringen i EU1. Trots att det mesta av dessa miljöfarliga aspekter kommer ifrån användningsphasen av den byggdamiljön, finns det en brist på omfattande hanteringssystem för miljörisker vid uppbyggnadsphasen. Denna studie föreslår en hanteringsmodell, baserad på Beer-Ziolkowski-modellen för riskhantering, som innehåller både byggplats baserade och icke byggplatsbaserade risker med en centrerad orientering vid just aktieägare samt andraberörda.Denna modell föreslår, att alla som skulle bli berörda vid förändring, engagerar sig för att identifiera risker med assistering utav strategisk vägledning hos den lämpliga förvaltningen - Kommunal- og regionaldepartementet samt med det närvarande organisationspraxisesn av indentifiering av de objektiva miljöriskerna med råd ifrån ISO140001. Omfattningarna av byggplats-beroende och icke byggplatsberoende riskkategorier fokuseras på layouten av byggplats och byggmaterial, enligt företagetsåsikt vilken av dessa två riskgrupper som är viktigast. Riskshantering föreslås med fel träanlys (FTA) metoden till byggplats beroende risker och European Union System for the Evaluation of Substances (EUSES) till icke byggplats beroende risker.Helkostnadsbokföring (TCA) för projektets olika alternativ rekommenderas som åtgärd för att inkludera de vanliga ytterliggande kostnaderna. En två spårig integration av risksbeskedet föreslås – katagoriserad riskminskning vid projektsnivå och vanliga goda affärsprincipier tillsammans med riskmedvetenhet på policy nivå.På grund av att modellen är en ram för riskhantering, som skilljer sig ifrån en metod fören särskild risk, granskas priciperna så som föreslaget med fallstudier för identifieringoch analys av risker.Genom att engagera aktieägare och andra intressenter men även natuvetenskaplig riskbedömning, ska denna modell hjälpa företaget till att möjligöra en säker bedrivningutav företagspraxisen i kombination med ett stärkt intresse utav miljöaspekter. I framtiden ska detta i sin tur ge företaget större kompetens när det gäller att planera och skapa en hållbar affärsplanering. / www.ima.kth.se