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Caractérisation structurale et fonctionnelle de la peptide déformylase du phage Vp16T / Structural and functional characterization of the phage Vp16T peptide deformylaseNusbaum, Julien 06 December 2016 (has links)
Les protéines en cours de synthèse subissent des modifications très précoces de leur extrémité N-terminale, dès lors que celle-ci émerge du tunnel de sortie du ribosome. La première modification est l’excision de la méthionine initiatrice, assurée par une méthionine aminopeptidase (MetAP), précédée de sa déformylation par une enzyme peptide déformylase (PDF) chez les bactéries et dans les mitochondries et chloroplastes. Ce processus est ubiquitaire et essentiel, et a été décrit dans tout le règne du vivant. Chez les bactéries, les PDFs de type 1B se fixeraient au ribosome à proximité de l’extrémité du tunnel de sortie du peptide naissant, via son hélice α C-terminale. Or des analyses métagénomiques récentes ont révélé la présence insoupçonnée de gènes codant des PDFs putatives chez des virus marins. De manière inattendue, toutes les PDF virales présentent des séquences C-terminales très courtes et dépourvues de l’hélice α3. L’identification de ces PDFs atypiques soulève alors de nouvelles questions quant à leur possible interaction au ribosome et à leur fonction biologique. L’objectif de ma thèse a donc été de réaliser la caractérisation complète et intégrée de la peptide déformylase du bactériophage Vp16T, dont la séquence est l’une des plus courtes connues à ce jour. J’ai montré que le phage Vp16T code une protéine active, in vivo et in vitro, et qu’elle peut se lier au ribosome malgré l’absence d’hélice α C-terminale. La caractérisation structure-fonction de Vp16PDF a révélé des caractéristiques uniques qui pourraient alors expliquer sa fonction au cours de la réplication du phage. Ainsi j’ai montré que l’expression de Vp16PDF chez E. coli modifie la structure de l’enveloppe, induit l’accumulation d’agrégats et finalement inhibe la croissance bactérienne. De plus, l’étude de souches bactériennes mutantes a montré que Vp16PDF interfère spécifiquement avec le repliement et l’adressage de protéines membranaires. Cette dernière fonction pourrait permettre de déstabiliser la membrane de l’hôte et ainsi favoriser la libération des particules virales. / Being synthesized proteins undergo very early changes in their N-terminal end, since it emerges from the outlet channel of the ribosome. The first modification is the excision of the initiator methionine, provided by a methionine aminopeptidase (MetAP), preceded by its deformylating enzyme peptide deformylase (PDF) in bacteria and in mitochondria and chloroplasts. This process is ubiquitous and essential, and has been described in the kingdom of life. In bacteria, Type 1B PDFs would bind to the ribosome near the end of the outlet tunnel of the nascent peptide via its C-terminal helix α. But recent metagenomic analyzes revealed the unexpected presence of genes encoding putative PDFs in marine viruses. Unexpectedly, all viral PDF have very short C-terminal sequences and lacking the α3 helix. The identification of these atypical PDFs then raises new questions about their possible interaction with ribosome and their biological function. The aim of my thesis was therefore to achieve the complete and integrated characterization of peptide deformylase bacteriophage Vp16T, the sequence is one of the shortest known to date. I showed that the phage Vp16T code an active protein in vivo and in vitro, and can bind to the ribosome despite the absence of the C-terminal helix α. The structure-function characterization Vp16PDF revealed unique features that could then explain its function in the replication of the phage. Thus I have shown that expression in E. coli Vp16PDF modifies the envelope structure, induces accumulation of aggregates and ultimately inhibits bacterial growth. In addition, the study of mutant bacterial strains showed that Vp16PDF specifically interfere with the folding and addressing of membrane proteins. This latter function could help destabilize the membrane of the host and thereby promote release of viral particles.
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Stimulating Non-Management Employees’ Contribution to Strategy Implementation : An Analysis of Non-Management Employees’ Strategically Aligned Behavior in the Strategy Implementation ProcessHansson, David, Mårtensson, Arvid January 2011 (has links)
The importance of strategy formulation is well known and has consequently received a lot of attention from researchers and managers alike, however, strategy is not of any use if it cannot be implemented successfully. The field of implementation has received more and more attention lately but there is still much left to study and understand. One gap in the area is related to non-managers as executors and how they can contribute to a successful implementation; the purpose in this study is therefore to provide an initial foundation to fill this gap but also to link the factors to a context. To gauge the success of implementation as influenced by the non-management, the smoothness of the implementation was considered, i.e. how frequent the problems were. The first step was therefore to find possible problems affected by the actions of the non-management and then to consider why they occurred. This was done with the help of the theory of strategy aligned behavior. A qualitative study using interviews with managers and employees from two medium-sized manufacturing companies within a regional cluster in southern Sweden was chosen to gain the necessary data in order to reach the purpose of our study. In the analysis of the research, the theory was found to be closely correlated to the empirical findings for the most part. With attention to the type of implementation discussed, the findings could be related to a context of where they occurred and then presented in a 2x2 matrix using measures of competence and company linkages. The findings include, as theory emphasizes; the importance of communication, not only in general but also in specific contexts. Further, an importance of the difference of strategic purpose and strategic effects could amongst other things also be seen.
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The Surrogate Country System for WTO Antidumping Investigations against Non-market-economy Countries: China as an ExampleChen, Yanni 21 November 2013 (has links)
This thesis examines the Surrogate Country System adopted by WTO members in their antidumping investigations against non-market-economy (NME) countries. In this paper, the Author points out that the existing relevant WTO regulations can easily become importing countries' tool of protectionism. Meanwhile, the obvious legal gap in the WTO laws helps the protectionism by leaving large discretion to importing countries. To reveal the irrationalities of the Surrogate Country System, this paper uses China, a typical NME country, as a sample to display how the system is applied in practice. Then, the paper examines the irrationalities of existing regulations. Towards above issues, the Author puts forward several proposals in Chapter 4. The Author argues for distinguishing transformational countries from NME countries. In cases involving transformational countries, the Author proposes a three-step methodology to calculate the normal value. The Author also provides several strategies for Chinese Government and exporters.
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The Surrogate Country System for WTO Antidumping Investigations against Non-market-economy Countries: China as an ExampleChen, Yanni 21 November 2013 (has links)
This thesis examines the Surrogate Country System adopted by WTO members in their antidumping investigations against non-market-economy (NME) countries. In this paper, the Author points out that the existing relevant WTO regulations can easily become importing countries' tool of protectionism. Meanwhile, the obvious legal gap in the WTO laws helps the protectionism by leaving large discretion to importing countries. To reveal the irrationalities of the Surrogate Country System, this paper uses China, a typical NME country, as a sample to display how the system is applied in practice. Then, the paper examines the irrationalities of existing regulations. Towards above issues, the Author puts forward several proposals in Chapter 4. The Author argues for distinguishing transformational countries from NME countries. In cases involving transformational countries, the Author proposes a three-step methodology to calculate the normal value. The Author also provides several strategies for Chinese Government and exporters.
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En studie av plattformsoberoende med Haxe och NMEEriksson Reimer, Henrik January 2012 (has links)
Det jag ska undersöka är hur väl program skrivna i Haxe med det externa biblioteket NME uppnår plattformsoberoende. Mer specifikt hur väl ett spel skrivet i Haxe med NME är plattformsoberoende givet att programkoden är den samma och inte modifierad för varje plattform. På hemsidan för NME ställs frågan ”Does This Actually Work?” och svaret som ges är ”As surprising as it sounds, NME really works. You do not need to spend your time messing with cross-platform compatibility, but you also do not have to sacrifice runtime performance or access to platform features.”. För att Haxe och NME ska anses vara plattformsoberoende ska samma källkod resultera i att spel som fungerar på ett tillfredsställande sätt på alla de testade plattformarna, givet att jag i programkoden tar hänsyn till den hårdvara som finns tillgänglig på plattformarna. En persondator har i regel tillgång till tangentbord och mus medan en smartphone i regel inte gör det. En smartphone har däremot tillgång till en touchscreen vilket majoriteten av persondatorer inte har. Med det i åtanke går det t.ex. inte att förvänta sig att ett program som är skrivet att enbart använda mus som inmatningsenhet att fungera på en plattform utan mus. Kriterierna för att spelet fungerar på ett tillfredsställande sätt är dessa: De funktioner som är listade i kravspecifikation i del 3.3 ska fungerar korrekt. Grafiken ska se likadan ut jämfört med på andra plattformar. Den genomsnittliga bilduppdateringsfrekvensen ska ha ett värde påminst 40 FPS. De plattformar jag kommer att testa spelet på är följande: Windows Ubuntu Mac OS X Android IOS För Windows, Ubuntu och Mac OS X kommer jag att testa spelet både i det plattformsoberoende Flash-formatet och som plattformsberoende C++ filer. Jag kommer att inkludera skärmbilder av spelet när det körs på de olika plattformarna som verifikation att spelet faktiskt fungerar samt att spelet ser likadant ut oavsett plattform. För att jämföra skillnaderna i bilduppdateringsfrekvens och för att se att minst 40 FPS uppnås så kommer bilduppdateringsfrekvensen att mätas för varje plattform. Annoterade skärmbilder som illustrerar hur det färdiga spelet fungerar kommer att ingå samt länkar till en screencast av spelet.
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Promoting Educational Change: Reflections on a Namibian Non-Governmental Educational Organisation 1989 - 1992Collett, Karen Suzette January 1999 (has links)
Magister Educationis - MEd / In this dissertation I set out to reflect on and examine a case study of a Namibian nongovernmental educational organisation (NGEO),the Primary Teachers Project (PTP),from 1989to 1992 focusing on issuesof educational change and the role of NGEO'sin this process. My aim is
to highlight some of the factors which helped and hindered the Primary Teachers Project playing a role in educational change. The study focuses on the following four aspects: The Primary Teachers Project'sin-service education and training (INSET)model. The relationship between the Namibian Ministry of Education and the PTP. Funding relationships and their influence on the project's development.
Internal dynamics within the Primary Teachers Project The dissertation begins by locating the Primary Teachers Project within the broader geographical, political and educational context of Namibia. The PTP's development between 1989 and 1992is then described. The four focus areas above are highlighted within the case study. Topical reflections on each of these areas are integrated with relevant national and international literature on INSET, educational change and the role of NGEO's. Central learnings with regard to the PTP and its role in educational change in Namibia are raised. Some of the key factors which worked for and against this NGEO's influence on educational change are highlighted. Finally, I make a number of general recommendations with regard to the role of NGEO's in the Southern African context. This study raises key factors relating to the influence of NGEO's on educational change. These are: NGEO's need to develop their understanding of the complexity of educational change processes, in order to inform INSET strategies. School-focused INSET models need to strengthen strategies for follow-up support to assist teachers to implement new ideas and practices. A combination of curriculum-based INSET and organisation development support needs to be provided at the school level to assist educational change. Organisation development processes within NGEO's can strengthen their internal capacity and critically inform their INSET strategies. NGEO's need to research and reflect on their practice and disseminate their findings, in order to improve their own practice and influence educational change at other levels of the educational system, Collaboration between different INSET providers builds the capacity for sustainability of educational change processes at school level and supports NGEO's in disseminating their knowledge and expertise throughout the formal educational system. An enabling INSET policy framework is required at national and local level to support INSET work in schools and assist the work of NGEO's and donors.
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