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Les gènes codant pour des protéines peuvent souvent être regroupés et intégrés en modules fonctionnels par rapport à un organelle. Ces modules peuvent avoir des composantes qui suivent une évolution corrélée pouvant être conditionnelle à un phénotype donné. Les gènes liés à la motilité possèdent cette caractéristique, car ils se suivent en cascade en réponse à des stimuli extérieurs. L’hyperthermophilie, d’autre part, est interreliée à la reverse gyrase, cependant aucun autre élément qui pourrait y être associé avec certitude n’est connu. Ceci peut être dû à un déplacement de gènes non orthologues encore non résolu. En utilisant une approche bio-informatique, une modélisation mathématique d’évolution conditionnelle corrélée pour trois gènes a été développée et appliquée sur des profils phylétiques d’archaea. Ceci a permis d’établir des théories quant à la fonction potentielle du gène du flagelle FlaD/E ainsi que l’histoire évolutive des gènes lui étant liés et ayant contribué à sa formation. De plus, une histoire évolutive théorique a été établie pour une ligase liée à l’hyperthermophilie. / Protein coding gene may often be grouped and integrated in functional modules with respect to an organelle. These modules may have constituents that follow a conditional correlated evolution to a given phenotype. Genes linked to motility posses this characteristic as they follow a cascade in response to external stimuli. Similarly, hyperthermophily is related to reverse gyrase, however no other element that could be associated with certainty is known. This may be caused by an unresolved case of non-orthologous gene displacement. Using a bioinformatic approach, a mathematical model for conditional correlated evolution for three genes has been developed and applied to the phyletic profiles of archaea. This has helped to develop theories about the potential functions of the flagellar gene FlaD/E and the evolutionary history of the genes that are linked to it and that may have contributed to its formation. In addition, a theoretical evolutionary history has been established for a ligase associated with hyperthermophily.

Hydraulic manipulators commonly interact with environments that are highly unstructured, and thus rely on the intelligence of human operators to provide proper commands. Typically, operators use visual information, directly or through cameras, to perform a task. Providing haptic or touch sensation about the task environment to the operator, enhances her/his ability to perform telemanipulation. The focus of this thesis is on haptic teleoperation of hydraulic manipulators. The application is directed at live transmission line maintenance tasks. In this thesis, both unilateral and bilateral haptic teleoperation of hydraulic manipulators are investigated. On the unilateral telemanipulation front, position error is shown to be an important issue in performing repetitive tasks. The most important sources of inaccuracy in position are sensors, robot controller performance, and the operator. To reduce the human operator’s errors, the concept of virtual fixtures is adopted in this research. It is shown that virtual fixtures can help operators perform routine tasks related to live line maintenance. Stability and telepresence are the main issues in reference to bilateral control. Three stable bilateral control schemes are designed for haptic teleoperation of hydraulic actuators considering nonlinear dynamics of hydraulic actuation, haptic device, and the operator. For each control scheme, stability of the entire control system is proven theoretically by constructing a proper Lyapunov function. Due to the discontinuity originating from a sign function in the control laws, the proposed control systems are non-smooth. Thus, the existence, continuation, and uniqueness of Filippov’s solution to the system are first proven for each control system. Next, the extensions of Lyapunov’s stability theory to non-smooth systems and LaSalle’s invariant set theorems are employed to prove the asymptotic stability of the control systems. In terms of telepresence, two types of haptic sensation are provided to the operator: (i) haptic based on the reflected interaction force, and (ii) haptic based on the position error. Performances of all proposed controllers are validated by experimental results on a hydraulic actuator controlled by a haptic device. It is shown that besides stability, the hydraulic actuator performs well in terms of position tracking while the haptic device provides telepresence for the operator.

As part of this project and in preparation for future experimental studies of gas-phase ion-molecule reactions, extensive modification and characterization of the crossed molecular beam machine in the Department of Chemistry, University of Canterbury has been carried out. This instrument has been configured and some preliminary testing completed to enable the future study of gas-phase ion-molecule collisions of H⁺₃ and Y⁻ (Y = F, Cl, Br) with dipole-oriented CZ₃X (Z = H, F and X = F, Cl, Br). Theoretical calculations (ab initio and density functional theory) are reported on previously experimentally characterized Na + CH₃NO₂, Na + CH₃NC, and K + CH₃NC systems, and several other systems of relevance. All gas-phase experimental and theoretical studies have the common theme of studying collision orientation dependence of reaction under singlecollision conditions. Experimental measurements, theoretical simulations and calculations are also reported on some selected ferrous (Fe²⁺) high-spin (S=2) crystals, in an attempt to resolve microscopic contributions of two fundamental macroscopic tensor properties: the electric-field gradient (efg); and the mean square displacement (msd) in the case when more than one symmetry related site of low local point-group symmetry contributes to the same quadrupole doublet. These determinations have been made using the nuclear spectroscopic technique of Mössbauer spectroscopy, and complemented with X-ray crystallographic measurements.

This thesis investigates ‘the doing’ of the Swedish social insurance program Activity Compensation (AC). AC is an example of disability policies in Western welfare states. These policies have two goals: to ensure financial security and to promote social participation. In 2003 AC replaced Early Retirement Pension for persons aged 19 to 29 years and who, for medical reasons, have reduced work capacity. Three features characterize AC. Young adults are differentiated in a separate system. For them, benefits are time-limited. Benefits include an established right to participate in activities. Doing AC is studied bottom-up. Interviews with two actor groups have provided the empirical base: 1) persons accorded AC and medically certified to have an anxiety and/or a depression diagnosis and 2) the respective administrator(s) at the Swedish Social Insurance Agency. National legislative preparatory texts and legal documents complete the data. The conclusions of this study are three-fold addressing goal displacement and non-contact. Firstly, a discursive change in respect to the denotation of social participation within the politics of principle has appeared throughout OECD countries over the last decennium. This goal displacement obscures the goal of economic security emphasizing the profitability of work. AC explicitly manifests this change in establishing a right to activity participation for beneficiaries. This displacement is without full impact in the politics of practice when actors’ experience of doing AC is examined. Financial security remains the foremost goal in the local politics of practice mirroring the initial function of safeguard for those with reduced work capacity due to certified illness. Relating to this lexical displacement, the study concludes that social participation is revealed as a goal to be realized in a specific form, salaried employment, within a distinct arena, the labor market. Values such as life-quality are neglected as regulatory efforts to get persons on the track to work have been underscored. Finally, the prescribed contact between the insured young adults and their administrator(s) is not consistently present. This contact is a necessary condition for the intended planning of activities to take place. When non-contact prevails, the established regulatory right to participate in activities can not materialize.

The aim of this thesis is to examine the rights of internally displaced persons as well as finding out whose responsibility it is to maintain these rights. The questions being answered are: what policies, laws and conventions are addressing internally displaced persons in Somalia (mainly from within Somalia, UN and AU)? And; which principal similarities and differences in these documents are to find regarding what type of protection internally displaced persons can get? Whose responsibility is it to intervene if these rights and rules are not maintained? To answer these questions I have used a liberal-universal theoretical framework. The analysis is a describing case study of comparative nature between the Provisional Somalia Constitution, UN Guiding Principles on Internal Displacement and the Kampala Convention. The result shows that there are many different rights of internally displaced persons in Somalia. Instead the problem seems to be based on the rights not being maintained in combination with the complex question of whose responsibility it is.

Hydraulic manipulators commonly interact with environments that are highly unstructured, and thus rely on the intelligence of human operators to provide proper commands. Typically, operators use visual information, directly or through cameras, to perform a task. Providing haptic or touch sensation about the task environment to the operator, enhances her/his ability to perform telemanipulation. The focus of this thesis is on haptic teleoperation of hydraulic manipulators. The application is directed at live transmission line maintenance tasks. In this thesis, both unilateral and bilateral haptic teleoperation of hydraulic manipulators are investigated. On the unilateral telemanipulation front, position error is shown to be an important issue in performing repetitive tasks. The most important sources of inaccuracy in position are sensors, robot controller performance, and the operator. To reduce the human operator’s errors, the concept of virtual fixtures is adopted in this research. It is shown that virtual fixtures can help operators perform routine tasks related to live line maintenance. Stability and telepresence are the main issues in reference to bilateral control. Three stable bilateral control schemes are designed for haptic teleoperation of hydraulic actuators considering nonlinear dynamics of hydraulic actuation, haptic device, and the operator. For each control scheme, stability of the entire control system is proven theoretically by constructing a proper Lyapunov function. Due to the discontinuity originating from a sign function in the control laws, the proposed control systems are non-smooth. Thus, the existence, continuation, and uniqueness of Filippov’s solution to the system are first proven for each control system. Next, the extensions of Lyapunov’s stability theory to non-smooth systems and LaSalle’s invariant set theorems are employed to prove the asymptotic stability of the control systems. In terms of telepresence, two types of haptic sensation are provided to the operator: (i) haptic based on the reflected interaction force, and (ii) haptic based on the position error. Performances of all proposed controllers are validated by experimental results on a hydraulic actuator controlled by a haptic device. It is shown that besides stability, the hydraulic actuator performs well in terms of position tracking while the haptic device provides telepresence for the operator.

DNA polymerase epsilon (Pol ε) is a multi-subunit B-family DNA polymerase that is involved in leading strand DNA replication in eukaryotes. DNA Pol ε in yeast consists of four subunits, Pol2, Dpb2, Dpb3, and Dpb4. Pol2 is the catalytic subunit and Dpb2, Dpb3, and Dpb4 are the accessory subunits. Pol2 can be further divided into an N-terminal catalytic core (Pol2core) containing both the polymerase and exonuclease active sites and a C-terminus domain. We determined the X-ray crystal structure of Pol2core at 2.2 Å bound to DNA and with an incoming dATP. Pol ε has typical fingers, palm, thumb, exonuclease, and N-terminal domains in common with all other B-family DNA polymerases. However, we also identified a seemingly novel domain we named the P-domain that only appears to be present in Pol ε. This domain partially encircles the nascent duplex DNA as it leaves the active site and contributes to the high intrinsic processivity of Pol ε. To ask if the crystal structure of Pol2core can serve as a model for catalysis by Pol ε, we investigated how the C-terminus of Pol2 and the accessory subunits of Pol ε influence the enzymatic mechanism by which Pol ε builds new DNA efficiently and with high fidelity. Pre-steady state kinetics revealed that the exonuclease and polymerization rates were comparable between Pol2core and Pol ε. However, a global fit of the data over five nucleotide-incorporation events revealed that Pol ε is slightly more processive than Pol2 core. The largest differences were observed when measuring the time for loading the polymerase onto a 3' primer-terminus and the subsequent incorporation of one nucleotide. We found that Pol ε needed less than a second to incorporate the first nucleotide, but it took several seconds for Pol2core to incorporate similar amounts of the first nucleotide. B-family polymerases have evolved an extended β-hairpin loop that is important for switching the primer terminus between the polymerase and exonuclease active sites. The high-resolution structure of Pol2core revealed that Pol ε does not possess an extended β-hairpin loop. Here, we show that Pol ε can processively transfer a mismatched 3' primer-terminus between the polymerase and exonuclease active sites despite the absence of a β-hairpin loop. Additionally we have characterized a series of amino acid substitutions in Pol ε that lead to altered partitioning of the 3'primer-terminus between the two active sites. In a final set of experiments, we investigated the ability of Pol ε to displace the downstream double-stranded DNA while carrying out DNA synthesis. Pol ε displaced only one base pair when encountering double-stranded DNA after filling a gap or a nick. However, exonuclease deficient Pol ε carries out robust strand displacement synthesis and can reach the end of the templates tested here. Similarly, an abasic site or a ribonucleotide on the 5'-end of the downstream primer was efficiently displaced but still only by one nucleotide. However, a flap on the 5'-end of the blocking primer resembling a D-loop inhibited Pol ε before it could reach the double-stranded junction. Our results are in agreement with the possible involvement of Pol ε in short-patch base excision repair and ribonucleotide excision repair but not in D-loop extension or long-patch base excision repair.

Les paramètres de l’exil, comme déplacement, se transforment aujourd’hui dans un contexte de mondialisation, interrogeant le rôle des nations alors que les sociétés impliquent de plus en plus de mobilité et de diversité culturelle. Cette condition d’exilé aux repères mouvants, inscrite dans une temporalité discontinue et dont l’expérience est toujours douloureuse, a donné lieu à une littérature prolifique dans le domaine des études littéraires au cours du 20e siècle. En quoi le 21e propose-t-il un regard différent sur cette condition ? Dans ce mémoire nous analyserons quatre œuvres contemporaines qui nous proposent différentes variations des transformations identitaires profondes qui caractérisent la condition d’exilé. Deux des grands axes autour desquels s’est articulée la condition d’exilé ont été développés par Edward Said, qui propose une posture critique et politique, et Julia Kristeva, qui présente l’exil comme une condition plutôt psychique. Suivant cette perspective analytique, l’autobiographie de Mourid Barghouti fait écho à la compréhension de l’exil telle que l’entend Said, en pleine autonomie instauratrice. Puis, le roman de Rawi Hage dans une expérience plus psychique de l’exil, plus traumatique et plus violente du vécu avant l’exil, suggère que le rapport avec le milieu environnant a un impact sur l’expérience de l’exil, alors que dans ce cas il reste dysfonctionnel, et qu’un rapport pathologique à l’existence peut ensuite se manifester. Ensuite, le roman d’Abla Farhoud expose la possibilité d’un dépassement de cette expérience pathologique de l’exil par la distance, celle de l’âge et de la prise de parole. Finalement, dans la pièce Incendies de Mouawad, l’expérience psychique de l’exil est dépassée à la fois par une traduction de l’indicible de la violence, par un retour sur les traumas précédant l’exil, et par un travail collectif – comme autres formes de distances. Cette dernière œuvre est donc porteuse d’une compréhension de l’exil impliquant une dimension psychique, tout en devenant critique et politique, telle que le révèlent les écrits de Jacques Rancière. À la lumière de ces analyses, la condition d’exilé réclame d’urgence un retour sur les traumas précédents, le trauma qu’est l’exil, afin qu’une autonomie, une créativité et un engagement s’en dégagent, dans une société, dans un monde plus grand que soi. Pour les trois derniers auteurs, c’est la société québécoise qui révèle à la fois une compréhension des problématiques majeures de la condition d’exilé et une ouverture face à celles-ci, en ce début de 21e siècle. / Exile is a condition of displacement and a phenomenon that affects great masses of people today. Although this experience exists since the proverbial beginning of time, its parameters are changing in the present context of globalization, which transforms the role of nations and where societies are characterized by greater mobility and cultural diversity. The profound psychological and cultural transformations of identity – inward and outward – to which people are confronted through displacement can be understood as a condition per se, an exilic condition. This condition with moving marks, and which develops in a discontinuous temporality and as a necessarily painful experience, has been the source of prolific literature and of literary studies in the 20th century and before. How, differently then, does the 21st century gaze at this condition ? In this thesis, four works are analyzed in which the authors present different visions of the exilic condition. Two main lines of thinking have been explored around this condition: Edward Said embraced a critical and political posture while Julia Kristeva conceived of exile in its psychological dimensions. Within these analytic perspectives, Mourid Barghouti’s autobiography has affinities with Said’s approach as it inaugurates an autonomous condition. Through Rawi Hage’s novel, a more psychological experience of exile is observed, one that is more violent and traumatic. It sheds light on the undeniable impact of the environment on the experience of exile in the host country. If the relation to the host country stays dysfunctional, a pathological attitude to the exilic experience may develop. Abla Farhoud’s novel explores the possible overcoming of the pathologies of exile through distance, age, time, and words, the distance needed for Dounia. Finally, the psychological limitations of exile can be overcome by translating the “unspeakable” in violence, by a return to the pre-exilic traumas, and by a collective sharing of this restorative work. Mouawad’s play also exposes the psychological dimension of exile, but it also maintains its critical and political ones. We observe through these analyses that the exilic condition demands a redressing of the traumas that preceded exile, understood as another trauma, so that the exiled can exist in an autonomous, creative and committed way in his or her society of adoption. For the last three authors, this society is Québec, which shows openness to, and comprehension of, the major issues of the exilic condition in the 21st century.