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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.
631

Le droit d'auteur sur la mise en scène

Roy, Véronyque 08 1900 (has links)
À la lecture de la Loi sur le droit d'auteur, il n'est pas clair que la mise en scène y soit protégée. C'est pourquoi nous nous questionnons sur la qualification juridique la plus adéquate pour la mise en scène. Le metteur en scène est-il un artiste-interprète ou un auteur? Après avoir étudié les caractéristiques artistiques des mises en scène, par types de productions et à la lumière de facteurs faisant varier la latitude du metteur en scène, nous étudions les différentes possibilités de qualification juridique de la mise en scène. Les possibilités sont vastes, car le metteur en scène évolue dans un cadre comprenant plusieurs intervenants. De plus, la mise en scène rencontre deux obstacles caractéristiques à sa qualification juridique en droit d'auteur: la fixation et l'originalité. Nous en venons à la conclusion que le metteur en scène est un auteur, car chacun des aspects de la mise en scène serait protégeable sous différentes qualifications juridiques. / Stage directions are not c1early protected under the current wording of the Copyright Law. This is why we wonder which legal qualification would be most appropriate. Is the stage director a performer or an author? We study the possibilities of legal qualification for stage direction, according to its artistic characteristics by production types, and considering the different factors which influence the Stage Director's liberty as well. The possibilities are vast since the Stage Director works in collaboration with several other intervening parties. Also, the Stage Director meets two typical obstacles: fixation and originality. We conclude that the Stage Director is an author because each and every aspect of the stage directions are copyrightable, under different legal qualifications.
632

Fonction de l'AmtB dans la régulation de la nitrogénase chez Rhodobacter capsulatus

Abdelmadjid, Imen 04 1900 (has links)
La fixation de l’azote diatomique est un processus très important à la vie, vu sa nécessité dans la biosynthèse de plusieurs molécules de base; acides aminés, acides nucléiques, etc. La réduction de l’azote en ammoniaque est catalysée par la nitrogénase, une enzyme consommatrice de beaucoup d’énergie étant donné qu’elle nécessite 20 à 30 moles d’ATP pour la réduction d’une mole d’azote. De ce fait une régulation rigoureuse est exigée afin de minimiser le gaspillage d’énergie. Plusieurs systèmes de contrôle sont connus, aussi bien au niveau post-traductionnel que traductionnel. Chez la bactérie photosynthétique pourpre non-sulfureuse R. capsulatus, la régulation de l’activité de la nitrogénase nécessite une panoplie de protéines dont la protéine membranaire AmtB, qui est impliquée dans le transport et la perception d’ammonium, et les protéines PII qui jouent plusieurs rôles clés dans la régulation de l’assimilation d’azote. Suite à l’ajout de l’ammonium dans le milieu, une inhibition réversible de l’activité de la nitrogénase est déclenchée via un mécanisme d’ADP-ribosylation de la nitrogénase. La séquestration de GlnK (une protéine PII) par l’AmtB permet à DraT, une ADP-ribosyltransférase, d’ajouter un groupement ADP-ribose sur la protéine-Fe de la nitrogénase l’empêchant ainsi de former un complexe avec la protéine-MoFe. Donc, le transfert d’électrons est bloqué, engendrant ainsi l’inhibition de l’activité de la nitrogénase qui dure aussi long que la concentration d’azote fixé reste élevé, phénomène appelé le « Switch-off/Switch-on » de la nitrogénase. Dans ce mémoire, pour mieux comprendre ce phénomène de régulation, des mutations ponctuelles au niveau de certains résidus conservés de la protéine AmtB, dont D338, G367, H193 et W237, étaient générées par mutagénèse dirigée, afin d’examiner d’avantage leur rôle dans le transport d’ammonium, la formation du complexe AmtB-GlnK, ainsi que dans le « Switch-off » et l’ADP-ribosylation. Les résultats permettent de conclure l’importance et la nécessité de certains résidus telle que le G367 dans la régulation de la nitrogénase et le transport d’ammonium, contrairement au résidu D338 qui ne semble pas être impliqué directement dans la régulation de l’activité de la nitrogénase. Ces résultats suggèrent d’autres hypothèses sur les rôles des acides aminés spécifiques d’AmtB dans ses fonctions comme transporteur et senseur d’ammonium. / The reduction of diatomic nitrogen is a very important biological process given the need of all organisms for fixed nitrogen for the biosynthesis of basic key molecules such as, amino acids, nucleic acids, etc.. The reduction of nitrogen to ammonia is catalyzed by nitrogenase, an enzyme with high energy demands since it requires 20 to 30 moles of ATP for the reduction of one mole of nitrogen. Therefore a strict control is required to minimize energy waste. Several systems of regulation are known, both at the translational and post-translational level. In the purple non-sulfur photosynthetic bacterium R. capsulatus, the post-translational regulation of nitrogenase activity requires an array of proteins, including; the membrane protein AmtB, implicated in the perception and transport of ammonium, and PII proteins, which play key roles in the regulation of nitrogen assimilation. Following the addition of ammonium to the medium nitrogenase activity is reversibly inhibited (nitrogenase switch-off) via a mechanism of ADP-ribosylation of nitrogenase. Sequestration of GlnK (PII protein) by AmtB allows DraT, an ADP-ribosyltransferase, to add an ADP-ribose group to the Fe protein preventing it from forming a complex with the MoFe protein and nitrogenase activity is consequently inhibited. To better understand this phenomenon, in this Master’s thesis point mutations were created by site-directed mutagenesis at specific conserved residues of the AmtB protein, namely, D338, G367, H193 and W237, in order to examine their role in ammonium transport, formation of an AmtB-GlnK complex, and the regulation of nitrogenase (Switch-off/ADP-ribosylation). Plasmid-borne mutant alleles were transferred to a ∆AmtB strain of R. capsulatus, and the resultant strains were subjected to a series of tests. These demonstrated the importance and necessity of certain residues, such as G367, in the regulation of nitrogenase and ammonium transport, in contrast to residue D338, which seems to have no direct role in the regulation of nitrogenase activity. These results suggest further hypotheses about the roles of specific amino acids of AmtB in its functions as a sensor and transporter for ammonium.
633

Les transformations microbiennes de l’azote dans les grandes rivières

Tall, Laure 02 1900 (has links)
Les rivières reçoivent de l'azote de leurs bassins versants et elles constituent les derniers sites de transformations des nutriments avant leur livraison aux zones côtières. Les transformations de l’azote inorganique dissous en azote gazeux sont très variables et peuvent avoir un impact à la fois sur l’eutrophisation des côtes et les émissions de gaz à effet de serre à l’échelle globale. Avec l’augmentation de la charge en azote d’origine anthropique vers les écosystèmes aquatiques, les modèles d’émissions de gaz à effet de serre prédisent une augmentation des émissions d’oxyde nitreux (N2O) dans les rivières. Les mesures directes de N2O dans le Lac Saint-Pierre (LSP), un élargissement du Fleuve Saint-Laurent (SLR) indiquent que bien qu’étant une source nette de N2O vers l'atmosphère, les flux de N2O dans LSP sont faibles comparés à ceux des autres grandes rivières et fleuves du monde. Les émissions varient saisonnièrement et inter-annuellement à cause des changements hydrologiques. Les ratios d’émissions N2O: N2 sont également influencés par l’hydrologie et de faibles ratios sont observés dans des conditions de débit d'eau plus élevée et de charge en N élevé. Dans une analyse effectuée sur plusieurs grandes rivières, la charge hydraulique des systèmes semble moduler la relation entre les flux de N2O annuels et les concentrations de nitrate dans les rivières. Dans SLR, des tapis de cyanobactéries colonisant les zones à faible concentration de nitrate sont une source nette d’azote grâce à leur capacité de fixer l’azote atmosphérique (N2). Étant donné que la fixation a lieu pendant le jour alors que les concentrations d'oxygène dans la colonne d'eau sont sursaturées, nous supposons que la fixation de l’azote est effectuée dans des micro-zones d’anoxie et/ou possiblement par des diazotrophes hétérotrophes. La fixation de N dans les tapis explique le remplacement de près de 33 % de la perte de N par dénitrification dans tout l'écosystème au cours de la période d'étude. Dans la portion du fleuve Hudson soumis à la marée, la dénitrification et la production de N2 est très variable selon le type de végétation. La dénitrification est associée à la dynamique en oxygène dissous particulière à chaque espèce durant la marée descendante. La production de N2 est extrêmement élevée dans les zones occupées par les plantes envahissantes à feuilles flottantes (Trapa natans) mais elle est négligeable dans la végétation indigène submergée. Une estimation de la production de N2 dans les lits de Trapa durant l’été, suggère que ces lits représentent une zone très active d’élimination de l’azote. En effet, les grands lits de Trapa ne représentent que 2,7% de la superficie totale de la portion de fleuve étudiée, mais ils éliminent entre 70 et 100% de l'azote total retenu dans cette section pendant les mois d'été et contribuent à près de 25% de l’élimination annuelle d’azote. / Rivers receive nitrogen (N) from their watershed and are the final sites of nutrient processing before delivery to coastal waters. Transformations of dissolved inorganic N (DIN) to gaseous N are highly variable and can impact both coastal eutrophication and greenhouse gas emissions. With anthropogenic N loading to aquatic ecosystems on the rise, nitrous oxide (N2O) emission from rivers should increase. Direct measurements of N2O from lake St. Pierre (LSP), an enlargement of the St. Lawrence River (SLR) indicate that although LSP is a net atmospheric source of N2O to the atmosphere fluxes are low compared to others rivers. Emissions are seasonally and inter-annually highly variable due to changes in hydrological conditions. N2O: N2 is also influenced by hydrology and lower ratios are observed in conditions of higher water discharge and elevated N charge into the ecosystem. In a cross system analysis, hydraulic load mitigates the relation between annual N2O flux and nitrate concentrations in rivers. In SLR, cyanobacterial mats colonizing low nitrate areas are a net source of N with high negative di-nitrogen (N2) fluxes. Given that fixation occurred during daylight and that oxygen concentrations in the water column were supersaturated, we hypothesize that N2 fixation is performed by the dominant cyanobacteria in anoxic micro-zone of the mat and/ or possibly by heterotrophic diazotrophs. Our estimates indicate that N fixation in the mats account for the replacement of up to 33% of the N loss via denitrification in the entire ecosystem during the study period. In the tidal Hudson River N2 production is highly variable between vegetated shallows and was associated with species-driven differences in dissolved oxygen (DO) dynamics during the ebb tide. N2 production was extremely high in invasive floating-leaved plants (Trapa natans) but was insignificant in submersed native vegetation. An estimate of summertime N2 production in Trapa beds suggests that these beds are a major seasonal hotspot for N removal. Large Trapa beds represent only 2.7% of the total area of the tidal Hudson but they remove between 70 and 100% of the total N retained in this section of the river during summer months and contribute to as much as 25% of the annual N removal.
634

Estudo randomizado da osteossíntese das fraturas da extremidade proximal do úmero com placa ou haste intramedular / Randomized trial on the proximal humerus fracture osteosynthesis with plate or intramedullary nailing

Gracitelli, Mauro Emilio Conforto 10 December 2015 (has links)
INTRODUÇÃO: As fraturas da extremidade proximal do úmero são frequentes, com incidência crescente no idoso e com impacto na qualidade de vida e na função do ombro. Para os casos com desvio, a placa bloqueada é o método mais utilizado de osteossíntese. Bons resultados clínicos são obtidos tanto com a placa bloqueada como com a haste intramedular bloqueada. O objetivo do estudo foi a comparação desses métodos no tratamento das fraturas da extremidade proximal do úmero quanto aos resultados clínicos, radiográficos e à taxa de complicações. MÉTODOS: Nesse estudo clínico prospectivo e randomizado, 72 pacientes com fraturas desviadas da extremidade proximal do úmero, classificadas como em 2 ou 3 partes de Neer, foram alocados para receberem osteossíntese com placa bloqueada (36 pacientes - Grupo Placa) ou haste intramedular bloqueada (36 pacientes - Grupo Haste). Os desfechos clínicos foram avaliados aos 3, 6 e 12 meses e incluíram as escalas de Constant e Murley, Universidade da Califórnia em Los Angeles modificada (UCLA), escala visual analógica de dor (EVA) e o questionário \"Disability of Arm, Shoulder and Hand\"(DASH) e a amplitude de movimento passiva. Os desfechos radiográficos consistiram na avaliação da consolidação e do ângulo cabeça-diáfise. As complicações foram avaliadas até os 12 meses e incluíram a avaliação do manguito rotador pela ultrassonografia. O desfecho primário do estudo foi a avaliação pela escala de Constant e Murley, aos 12 meses de pós-operatório. RESULTADOS: Sessenta e cinco pacientes completaram 12 meses de seguimento, sendo 32 no Grupo Haste e 33 no Grupo Placa. A escala de Constant aos 12 meses foi de 70,3 pontos para o Grupo Haste e de 71,5 pontos para o Grupo Placa (p = 0,750). A escala de Constant Relativa Individual foi de 81% para o Grupo Haste e de 85% para o Grupo Placa (p = 0,400). Também não houve diferença entre os grupos aos 3 e 6 meses para a escala de Constant. A escala EVA e o questionário DASH também não apresentaram diferença aos 3, 6 e 12 meses, assim como os resultados radiográficos. A escala UCLA apresentou diferença de 4,0 pontos aos 3 meses, com melhores resultados para o Grupo Haste (p = 0,005), mas sem diferença significante aos 6 e 12 meses. A amplitude de movimento apresentou diferença de 2,1 pontos favorável ao Grupo Haste para a rotação medial aos 6 meses (p = 0,042), sem diferença para os demais planos de movimento nos diferentes momentos de avaliação. Foram registradas 38 complicações, sendo 28 no Grupo Haste e 10 no Grupo Placa, com diferença estatística (p = 0,001). As complicações ocorreram em 18 pacientes, sendo 11 (34%) do Grupo Haste e sete (21%) do Grupo Placa, sem diferença estatística (p = 0,137). CONCLUSÕES: A osteossíntese das fraturas da extremidade proximal do úmero com placa bloqueada ou haste intramedular bloqueada produziram resultados clínicos e radiográficos semelhantes. A fixação com haste intramedular bloqueada apresentou maior taxa de complicações e reoperações / INTRODUCTION: Fractures of the proximal humerus are common, with an increasing incidence in the elderly and with a high impact on quality of life and shoulder function. For displaced fractures, the locking plate is the most used method of osteosynthesis. Studies have shown good clinical results with the use of locking plates, but also with the fixation with locking intramedullary nail. The aim of this study was to compare the clinical outcomes, radiographic results and the complications between these two methods in patients with displaced proximal humerus fractures. METHODS: In this prospective, randomized clinical trial, 72 patients with displaced fractures of the proximal humerus, classified as Neer 2- or 3-part, were randomly assigned to receive osteosynthesis with either locking plate (36 patients - Plate Group) or locking intramedullary nail (36 patients - Nail Group). The clinical outcomes were evaluated at 3, 6 and 12 months and included the Constant and Murley, University of California at Los Angeles (UCLA) and Disability of Arm, Shoulder and Hand (DASH) scores, visual analog scale (VAS) and the passive range of motion. Radiographic findings (consolidation and head shaft angle) and complications, which included the evaluation of rotator cuff by ultrasound, were also evaluated. The primary outcome was the Constant and Murley score at 12 months. RESULTS: Sixty-five patients completed 12 months of follow-up, 32 in the Nail Group and 33 in the Plate Group. The mean Constant score at 12 months was 70.3 points for the Nail Group and 71.5 points for the Plate Group (p = 0.750) and the mean Relative Constant score was 81% for the Nail Group and 85% points for the Plate Group (p = 0.400). There was also no difference at 3 and 6 months for the Constant score. VAS, DASH and radiographic findings also did not differ at 3, 6 and 12 months. Range of motion showed a 2.1 points difference in favor of the Nail Group for medial rotation at 6 months (p = 0.042), with no difference for the other motions at 3, 6 and 12 months. The UCLA score presented a difference of 4.0 points at 3 months, with better results for the Nail Group (p = 0.005), but no significant difference at 6 and 12 months. Thirty-eight complications were recorded, 28 in the Nail Group and 10 in the Plate Group, with significant difference (p = 0.001). Complications occurred in 18 patients, 11 (34%) of the Nail Group and seven (21%) of the Plate Group, with no significant difference (p = 0.137). CONCLUSIONS: Locking plates and locking intramedullary nail yielded similar clinical and radiographic results. Locking intramedullary nail fixation has a higher risk for complications and reoperations
635

Estudo comparativo entre a haste intramedular bloqueada e a placa em ponte no tratamento cirúrgico das fraturas da diáfise do úmero / Comparative study using nonreamed intramedullary locking nail and bridging plate for the treatment of humeral shaft fractures

Benegas, Eduardo 10 December 2008 (has links)
O objetivo deste estudo é o de comparar os resultados clínicos e radiográficos do tratamento cirúrgico das fraturas da diáfise do úmero com haste intramedular bloqueada ou placa em ponte. Quarenta fraturas da diáfise do úmero, em 39 pacientes, dos tipos A, B ou C da classificação do grupo A.O., foram tratadas no período compreendido entre junho de 2003 e dezembro de 2007. Destas, após seleção por sorteio, 21 fraturas foram submetidas à osteossíntese com placas em ponte de 4,5 mm e parafusos (grupo PP) e 19 com hastes intramedulares bloqueadas não fresadas (grupo HIB). Duas eram fraturas expostas, uma do tipo II e outra do tipo III-a de Gustilo. Vinte e cinco pacientes eram do sexo masculino (64%) e a idade variou de 19 a 75 anos (idade média de 41 anos e 10 meses). O lado direito foi acometido em 22 pacientes (55%) e a queda, o mecanismo de trauma mais freqüente (46%). O tempo mínimo de seguimento foi de seis meses e o máximo de 60 meses para o grupo PP (M=34,5 meses) e de oito e 58 meses (M=27meses) para o grupo HIB. Em apenas um caso, operado com haste intramedular bloqueada, não houve a consolidação. Houve um caso de infecção profunda no grupo PP e um de infecção superficial no grupo HIB. Dois casos do grupo PP evoluíram com capsulite adesiva e, em apenas um dos casos do grupo HIB, o parafuso distal ficou saliente. Ocorreu neuropraxia do nervo cutâneo lateral do antebraço em um dos casos do grupo HIB que regrediu em três dias. Não houve diferença entre os grupos com relação ao tempo total da cirurgia. O tempo de utilização da radioscopia no ato operatório foi maior no grupo HIB. Houve semelhança entre os dois métodos de fixação nos resultados referentes à dor, à função, à flexão ativa e à força de flexão na articulação do ombro e também com relação à dor, mobilidade, força muscular e estabilidade na articulação do cotovelo. Segundo os critérios da UCLA para o ombro, obtivemos resultados excelentes e bons em 85,7% no grupo operado com placa em ponte e 79% no grupo com haste intramedular bloqueada e de acordo com os critérios de Broberg e Morrey para o cotovelo, obtivemos resultados excelentes e bons em 85,7% no grupo operado com placa em ponte e 90,5% no grupo com haste intramedular bloqueada. Na avaliação subjetiva, duas pacientes, uma do grupo HIB e outra do PP, não ficaram satisfeitas. Conclusão: Não houve diferença no resultado clínico e radiográfico entre os dois métodos / The purpose of the study is to compare clinical and radiographic outcomes between nonreamed locked intramedullary nail and bridging plate for the treatment of humeral shaft fracture. Forty humeral shaft fractures in 39 patients, A, B or C AO types were treated between June 2003 and December 2007. The cases were randomly assigned into two groups being 21 fractures fixed by a 4.5 mm bridging plate, and 19 by nonreamed intramedullary locking nail. Two cases had open fractures, one Gustilo type II, the other type IIIa. Twenty five patients were male (64%), ages ranging from 19 to 75 years old (mean age 41 years and 10 months). The right side was treated in 22 patients (55%) and fall was the most frequent cause of fracture (46%). The minimal period of follow-up was six months and the maximum was 60 months for the bridging plate group (mean=34.5 months) and ranged from eight to 58 months (mean=27months) for the nail group. Only one case from the nail group presented a nonunion. One case, in the plate group, developed a deep infection, and another one, in the nail group, had a superficial infection. Two cases of the bridging plate group had adhesive capsulites and in one case of the nail group the distal screw became prominent. A transient neuropraxis of the antebrachial lateral cutaneous nerve was found in one case of the nail group, but it recovered in three days. There were no differences between the groups concerning pain, function, active flexion and strength of flexion of the shoulder, as well as pain, range of motion, muscle strength, and stability of the elbow. According to the UCLA score, we had 85.7% excellent and good results in the plate group and 79% in the nail group. According to Broberg and Morrey score for the elbow, we had 85.7% excellent and good results in the plate group and 90.5% in the nail group. Just one patient, from the nail group, was not satisfied with the final result, according to subjective criteria. In conclusion, there were no differences in the final clinical and radiographic results between the two methods of fixation
636

Estudo randomizado da osteossíntese das fraturas da extremidade proximal do úmero com placa ou haste intramedular / Randomized trial on the proximal humerus fracture osteosynthesis with plate or intramedullary nailing

Mauro Emilio Conforto Gracitelli 10 December 2015 (has links)
INTRODUÇÃO: As fraturas da extremidade proximal do úmero são frequentes, com incidência crescente no idoso e com impacto na qualidade de vida e na função do ombro. Para os casos com desvio, a placa bloqueada é o método mais utilizado de osteossíntese. Bons resultados clínicos são obtidos tanto com a placa bloqueada como com a haste intramedular bloqueada. O objetivo do estudo foi a comparação desses métodos no tratamento das fraturas da extremidade proximal do úmero quanto aos resultados clínicos, radiográficos e à taxa de complicações. MÉTODOS: Nesse estudo clínico prospectivo e randomizado, 72 pacientes com fraturas desviadas da extremidade proximal do úmero, classificadas como em 2 ou 3 partes de Neer, foram alocados para receberem osteossíntese com placa bloqueada (36 pacientes - Grupo Placa) ou haste intramedular bloqueada (36 pacientes - Grupo Haste). Os desfechos clínicos foram avaliados aos 3, 6 e 12 meses e incluíram as escalas de Constant e Murley, Universidade da Califórnia em Los Angeles modificada (UCLA), escala visual analógica de dor (EVA) e o questionário \"Disability of Arm, Shoulder and Hand\"(DASH) e a amplitude de movimento passiva. Os desfechos radiográficos consistiram na avaliação da consolidação e do ângulo cabeça-diáfise. As complicações foram avaliadas até os 12 meses e incluíram a avaliação do manguito rotador pela ultrassonografia. O desfecho primário do estudo foi a avaliação pela escala de Constant e Murley, aos 12 meses de pós-operatório. RESULTADOS: Sessenta e cinco pacientes completaram 12 meses de seguimento, sendo 32 no Grupo Haste e 33 no Grupo Placa. A escala de Constant aos 12 meses foi de 70,3 pontos para o Grupo Haste e de 71,5 pontos para o Grupo Placa (p = 0,750). A escala de Constant Relativa Individual foi de 81% para o Grupo Haste e de 85% para o Grupo Placa (p = 0,400). Também não houve diferença entre os grupos aos 3 e 6 meses para a escala de Constant. A escala EVA e o questionário DASH também não apresentaram diferença aos 3, 6 e 12 meses, assim como os resultados radiográficos. A escala UCLA apresentou diferença de 4,0 pontos aos 3 meses, com melhores resultados para o Grupo Haste (p = 0,005), mas sem diferença significante aos 6 e 12 meses. A amplitude de movimento apresentou diferença de 2,1 pontos favorável ao Grupo Haste para a rotação medial aos 6 meses (p = 0,042), sem diferença para os demais planos de movimento nos diferentes momentos de avaliação. Foram registradas 38 complicações, sendo 28 no Grupo Haste e 10 no Grupo Placa, com diferença estatística (p = 0,001). As complicações ocorreram em 18 pacientes, sendo 11 (34%) do Grupo Haste e sete (21%) do Grupo Placa, sem diferença estatística (p = 0,137). CONCLUSÕES: A osteossíntese das fraturas da extremidade proximal do úmero com placa bloqueada ou haste intramedular bloqueada produziram resultados clínicos e radiográficos semelhantes. A fixação com haste intramedular bloqueada apresentou maior taxa de complicações e reoperações / INTRODUCTION: Fractures of the proximal humerus are common, with an increasing incidence in the elderly and with a high impact on quality of life and shoulder function. For displaced fractures, the locking plate is the most used method of osteosynthesis. Studies have shown good clinical results with the use of locking plates, but also with the fixation with locking intramedullary nail. The aim of this study was to compare the clinical outcomes, radiographic results and the complications between these two methods in patients with displaced proximal humerus fractures. METHODS: In this prospective, randomized clinical trial, 72 patients with displaced fractures of the proximal humerus, classified as Neer 2- or 3-part, were randomly assigned to receive osteosynthesis with either locking plate (36 patients - Plate Group) or locking intramedullary nail (36 patients - Nail Group). The clinical outcomes were evaluated at 3, 6 and 12 months and included the Constant and Murley, University of California at Los Angeles (UCLA) and Disability of Arm, Shoulder and Hand (DASH) scores, visual analog scale (VAS) and the passive range of motion. Radiographic findings (consolidation and head shaft angle) and complications, which included the evaluation of rotator cuff by ultrasound, were also evaluated. The primary outcome was the Constant and Murley score at 12 months. RESULTS: Sixty-five patients completed 12 months of follow-up, 32 in the Nail Group and 33 in the Plate Group. The mean Constant score at 12 months was 70.3 points for the Nail Group and 71.5 points for the Plate Group (p = 0.750) and the mean Relative Constant score was 81% for the Nail Group and 85% points for the Plate Group (p = 0.400). There was also no difference at 3 and 6 months for the Constant score. VAS, DASH and radiographic findings also did not differ at 3, 6 and 12 months. Range of motion showed a 2.1 points difference in favor of the Nail Group for medial rotation at 6 months (p = 0.042), with no difference for the other motions at 3, 6 and 12 months. The UCLA score presented a difference of 4.0 points at 3 months, with better results for the Nail Group (p = 0.005), but no significant difference at 6 and 12 months. Thirty-eight complications were recorded, 28 in the Nail Group and 10 in the Plate Group, with significant difference (p = 0.001). Complications occurred in 18 patients, 11 (34%) of the Nail Group and seven (21%) of the Plate Group, with no significant difference (p = 0.137). CONCLUSIONS: Locking plates and locking intramedullary nail yielded similar clinical and radiographic results. Locking intramedullary nail fixation has a higher risk for complications and reoperations
637

Following the mevalonate pathway to bone heal alley

Skoglund, Björn January 2007 (has links)
The mevalonate pathway is an important biosynthetic pathway, found in all cells of virtually all known pro- as well as eukaryotic organisms. This thesis is an investigation into the use of two drugs, originally developed for different applications, but both affecting the mevalonate pathway, in to models of fracture repair. Using two different rodent models of fracture repair, a commonly used cholesterol lowering drug (statin) and two drugs used to treat osteoporosis (bisphosphonate) were applied both systemically as well as locally in order to enhance fracture repair. Papers I and II investigate the potential of simvastatin to improve the healing of femoral fractures in mice. Papers III and IV explore the use of two bisphosphonates to improve early fixation of stainless steel screws into rat bone. The statin simvastatin lead to an increased strength of the healing cellus. The application of bisphosphonates increased early screw fixation. It seems clear that both drugs have uses in orthopaedic applications. One interesting avenue of further research would be to combine the two classes of drugs and see if we can get the benefits while at the same time diminishing the drawbacks.
638

Le droit d'auteur sur la mise en scène

Roy, Véronyque 08 1900 (has links)
À la lecture de la Loi sur le droit d'auteur, il n'est pas clair que la mise en scène y soit protégée. C'est pourquoi nous nous questionnons sur la qualification juridique la plus adéquate pour la mise en scène. Le metteur en scène est-il un artiste-interprète ou un auteur? Après avoir étudié les caractéristiques artistiques des mises en scène, par types de productions et à la lumière de facteurs faisant varier la latitude du metteur en scène, nous étudions les différentes possibilités de qualification juridique de la mise en scène. Les possibilités sont vastes, car le metteur en scène évolue dans un cadre comprenant plusieurs intervenants. De plus, la mise en scène rencontre deux obstacles caractéristiques à sa qualification juridique en droit d'auteur: la fixation et l'originalité. Nous en venons à la conclusion que le metteur en scène est un auteur, car chacun des aspects de la mise en scène serait protégeable sous différentes qualifications juridiques. / Stage directions are not c1early protected under the current wording of the Copyright Law. This is why we wonder which legal qualification would be most appropriate. Is the stage director a performer or an author? We study the possibilities of legal qualification for stage direction, according to its artistic characteristics by production types, and considering the different factors which influence the Stage Director's liberty as well. The possibilities are vast since the Stage Director works in collaboration with several other intervening parties. Also, the Stage Director meets two typical obstacles: fixation and originality. We conclude that the Stage Director is an author because each and every aspect of the stage directions are copyrightable, under different legal qualifications.
639

Fonction de l'AmtB dans la régulation de la nitrogénase chez Rhodobacter capsulatus

Abdelmadjid, Imen 04 1900 (has links)
La fixation de l’azote diatomique est un processus très important à la vie, vu sa nécessité dans la biosynthèse de plusieurs molécules de base; acides aminés, acides nucléiques, etc. La réduction de l’azote en ammoniaque est catalysée par la nitrogénase, une enzyme consommatrice de beaucoup d’énergie étant donné qu’elle nécessite 20 à 30 moles d’ATP pour la réduction d’une mole d’azote. De ce fait une régulation rigoureuse est exigée afin de minimiser le gaspillage d’énergie. Plusieurs systèmes de contrôle sont connus, aussi bien au niveau post-traductionnel que traductionnel. Chez la bactérie photosynthétique pourpre non-sulfureuse R. capsulatus, la régulation de l’activité de la nitrogénase nécessite une panoplie de protéines dont la protéine membranaire AmtB, qui est impliquée dans le transport et la perception d’ammonium, et les protéines PII qui jouent plusieurs rôles clés dans la régulation de l’assimilation d’azote. Suite à l’ajout de l’ammonium dans le milieu, une inhibition réversible de l’activité de la nitrogénase est déclenchée via un mécanisme d’ADP-ribosylation de la nitrogénase. La séquestration de GlnK (une protéine PII) par l’AmtB permet à DraT, une ADP-ribosyltransférase, d’ajouter un groupement ADP-ribose sur la protéine-Fe de la nitrogénase l’empêchant ainsi de former un complexe avec la protéine-MoFe. Donc, le transfert d’électrons est bloqué, engendrant ainsi l’inhibition de l’activité de la nitrogénase qui dure aussi long que la concentration d’azote fixé reste élevé, phénomène appelé le « Switch-off/Switch-on » de la nitrogénase. Dans ce mémoire, pour mieux comprendre ce phénomène de régulation, des mutations ponctuelles au niveau de certains résidus conservés de la protéine AmtB, dont D338, G367, H193 et W237, étaient générées par mutagénèse dirigée, afin d’examiner d’avantage leur rôle dans le transport d’ammonium, la formation du complexe AmtB-GlnK, ainsi que dans le « Switch-off » et l’ADP-ribosylation. Les résultats permettent de conclure l’importance et la nécessité de certains résidus telle que le G367 dans la régulation de la nitrogénase et le transport d’ammonium, contrairement au résidu D338 qui ne semble pas être impliqué directement dans la régulation de l’activité de la nitrogénase. Ces résultats suggèrent d’autres hypothèses sur les rôles des acides aminés spécifiques d’AmtB dans ses fonctions comme transporteur et senseur d’ammonium. / The reduction of diatomic nitrogen is a very important biological process given the need of all organisms for fixed nitrogen for the biosynthesis of basic key molecules such as, amino acids, nucleic acids, etc.. The reduction of nitrogen to ammonia is catalyzed by nitrogenase, an enzyme with high energy demands since it requires 20 to 30 moles of ATP for the reduction of one mole of nitrogen. Therefore a strict control is required to minimize energy waste. Several systems of regulation are known, both at the translational and post-translational level. In the purple non-sulfur photosynthetic bacterium R. capsulatus, the post-translational regulation of nitrogenase activity requires an array of proteins, including; the membrane protein AmtB, implicated in the perception and transport of ammonium, and PII proteins, which play key roles in the regulation of nitrogen assimilation. Following the addition of ammonium to the medium nitrogenase activity is reversibly inhibited (nitrogenase switch-off) via a mechanism of ADP-ribosylation of nitrogenase. Sequestration of GlnK (PII protein) by AmtB allows DraT, an ADP-ribosyltransferase, to add an ADP-ribose group to the Fe protein preventing it from forming a complex with the MoFe protein and nitrogenase activity is consequently inhibited. To better understand this phenomenon, in this Master’s thesis point mutations were created by site-directed mutagenesis at specific conserved residues of the AmtB protein, namely, D338, G367, H193 and W237, in order to examine their role in ammonium transport, formation of an AmtB-GlnK complex, and the regulation of nitrogenase (Switch-off/ADP-ribosylation). Plasmid-borne mutant alleles were transferred to a ∆AmtB strain of R. capsulatus, and the resultant strains were subjected to a series of tests. These demonstrated the importance and necessity of certain residues, such as G367, in the regulation of nitrogenase and ammonium transport, in contrast to residue D338, which seems to have no direct role in the regulation of nitrogenase activity. These results suggest further hypotheses about the roles of specific amino acids of AmtB in its functions as a sensor and transporter for ammonium.
640

Les transformations microbiennes de l’azote dans les grandes rivières

Tall, Laure 02 1900 (has links)
Les rivières reçoivent de l'azote de leurs bassins versants et elles constituent les derniers sites de transformations des nutriments avant leur livraison aux zones côtières. Les transformations de l’azote inorganique dissous en azote gazeux sont très variables et peuvent avoir un impact à la fois sur l’eutrophisation des côtes et les émissions de gaz à effet de serre à l’échelle globale. Avec l’augmentation de la charge en azote d’origine anthropique vers les écosystèmes aquatiques, les modèles d’émissions de gaz à effet de serre prédisent une augmentation des émissions d’oxyde nitreux (N2O) dans les rivières. Les mesures directes de N2O dans le Lac Saint-Pierre (LSP), un élargissement du Fleuve Saint-Laurent (SLR) indiquent que bien qu’étant une source nette de N2O vers l'atmosphère, les flux de N2O dans LSP sont faibles comparés à ceux des autres grandes rivières et fleuves du monde. Les émissions varient saisonnièrement et inter-annuellement à cause des changements hydrologiques. Les ratios d’émissions N2O: N2 sont également influencés par l’hydrologie et de faibles ratios sont observés dans des conditions de débit d'eau plus élevée et de charge en N élevé. Dans une analyse effectuée sur plusieurs grandes rivières, la charge hydraulique des systèmes semble moduler la relation entre les flux de N2O annuels et les concentrations de nitrate dans les rivières. Dans SLR, des tapis de cyanobactéries colonisant les zones à faible concentration de nitrate sont une source nette d’azote grâce à leur capacité de fixer l’azote atmosphérique (N2). Étant donné que la fixation a lieu pendant le jour alors que les concentrations d'oxygène dans la colonne d'eau sont sursaturées, nous supposons que la fixation de l’azote est effectuée dans des micro-zones d’anoxie et/ou possiblement par des diazotrophes hétérotrophes. La fixation de N dans les tapis explique le remplacement de près de 33 % de la perte de N par dénitrification dans tout l'écosystème au cours de la période d'étude. Dans la portion du fleuve Hudson soumis à la marée, la dénitrification et la production de N2 est très variable selon le type de végétation. La dénitrification est associée à la dynamique en oxygène dissous particulière à chaque espèce durant la marée descendante. La production de N2 est extrêmement élevée dans les zones occupées par les plantes envahissantes à feuilles flottantes (Trapa natans) mais elle est négligeable dans la végétation indigène submergée. Une estimation de la production de N2 dans les lits de Trapa durant l’été, suggère que ces lits représentent une zone très active d’élimination de l’azote. En effet, les grands lits de Trapa ne représentent que 2,7% de la superficie totale de la portion de fleuve étudiée, mais ils éliminent entre 70 et 100% de l'azote total retenu dans cette section pendant les mois d'été et contribuent à près de 25% de l’élimination annuelle d’azote. / Rivers receive nitrogen (N) from their watershed and are the final sites of nutrient processing before delivery to coastal waters. Transformations of dissolved inorganic N (DIN) to gaseous N are highly variable and can impact both coastal eutrophication and greenhouse gas emissions. With anthropogenic N loading to aquatic ecosystems on the rise, nitrous oxide (N2O) emission from rivers should increase. Direct measurements of N2O from lake St. Pierre (LSP), an enlargement of the St. Lawrence River (SLR) indicate that although LSP is a net atmospheric source of N2O to the atmosphere fluxes are low compared to others rivers. Emissions are seasonally and inter-annually highly variable due to changes in hydrological conditions. N2O: N2 is also influenced by hydrology and lower ratios are observed in conditions of higher water discharge and elevated N charge into the ecosystem. In a cross system analysis, hydraulic load mitigates the relation between annual N2O flux and nitrate concentrations in rivers. In SLR, cyanobacterial mats colonizing low nitrate areas are a net source of N with high negative di-nitrogen (N2) fluxes. Given that fixation occurred during daylight and that oxygen concentrations in the water column were supersaturated, we hypothesize that N2 fixation is performed by the dominant cyanobacteria in anoxic micro-zone of the mat and/ or possibly by heterotrophic diazotrophs. Our estimates indicate that N fixation in the mats account for the replacement of up to 33% of the N loss via denitrification in the entire ecosystem during the study period. In the tidal Hudson River N2 production is highly variable between vegetated shallows and was associated with species-driven differences in dissolved oxygen (DO) dynamics during the ebb tide. N2 production was extremely high in invasive floating-leaved plants (Trapa natans) but was insignificant in submersed native vegetation. An estimate of summertime N2 production in Trapa beds suggests that these beds are a major seasonal hotspot for N removal. Large Trapa beds represent only 2.7% of the total area of the tidal Hudson but they remove between 70 and 100% of the total N retained in this section of the river during summer months and contribute to as much as 25% of the annual N removal.

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