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Chain conformations and the presence of chain overlaps and entanglements in dilute polymer solutions have been analyzed. The fundamental problem of existence of chain overlaps in dilute solutions is related to the drag reduction phenomenon (DR). Even though DR occurs in solutions with the concentration of only few parts per million (ppm), some theories suggest that entanglements may play an important role in DR mechanism. Brownian dynamics technique have been used to perform simulations of dilute polymer solutions at rest and under shear flow. A measure of interchain contacts and two different measures of entanglements have been devised to evaluate the structure of polymer chains in solution. Simulation results have shown that overlaps and entanglements do exist in static dilute solutions as well as in solutions under shear flow. The effect of solution concentration, shear rate and molecular mass have been examined. In agreement with the solvation theory of DR mechanism, simulation results have demonstrated the importance of polymer + polymer interactions in dilute solutions.

Neste trabalho, descrevemos vários protocolos para a geração de estados estacionários não clássicos, suportados principalmente pela engenharia de hamiltonianos seletivos Jaynes-Cummings, e de reservatórios atômicos. Começamos apresentando um protocolo para engenhar interações seletivas lineares e não lineares do tipo Jaynes-Cummings como também simulações numéricas para comprovar a eficácia de nosso esquema. Analisamos também como aplicar essas interações seletivas à preparação e proteção de estados de Fock estacionários via reservatório atômico. Esta estratégia combina a ação dos mecanismo de amortecimento da cavidade com os de um reservatório atômico engenhado para conduzir uma distribuição térmica inicial a um estado de Fock estacionário. A mesma técnica pode ser utilizada para fatiar as distribuições de probabilidade no espaço de Fock, permitindo assim a preparação de uma variedade de estados de equilíbrio não clássicos. Também apresentamos um protocolo para a engenharia de interações upper-bound e sliced Jaynes-Cummings e anti-Jaynes-Cummings na eletrodinâmica quântica de cavidade. No Hamiltoniano upper-bound, a interação átomo-campo está confinada a um subespaço de Fock com estados que vão desde Ι0> até Ι4> enquanto que no Hamiltoniano sliced vão desde ΙM> até ΙM + 4>. Mostramos como construir Liouvillianos upper-bound independentemente da engenharia do Hamiltoniano upper-bound. Os Hamiltonianos e Liouvillianos upper-bound e sliced podem ser usados, entre outras aplicações, para gerar estados de Fock estacionários no modo da cavidade e para a implementação de um dispositivo de tesoura quântica para truncagem de estado óptico. Finalmente, propomos um esquema para a preparação de estados emaranhados estacionários em redes bosônicas dissipativas. Descrevemos a sua aplicação em um sistema de cavidades acopladas interagindo com um reservatório construído por átomos de três níveis. Os emblemáticos estados Bell e NOON, e estados multipartites (tipo W) podem ser produzidos com alta fidelidade e pureza. / In this work, we describe various protocols for the generation of nonclassical steady-state, supported mainly by the engineering selective Hamiltonian Jaynes-Cummings-type, and atomics reservoirs. We started presenting a framework to engineer nonlinear selective JaynesCummings-type interactions with numerical simulations to prove the effectiveness of our scheme. We further analyses how to apply these selective interactions to the preparation and protection of steady Fock states via atomic reservoir. This strategy combines the action of cavity damping mechanisms with that of an engineered atomic reservoir to drive an initial thermal distribution to a Fock equilibrium state. The same technique can be used to slice probability distributions in the Fock space, thus allowing the preparation of a variety of non-classical equilibrium states. Also we present a protocol to engineer upper-bound and sliced Jaynes-Cummings-type and anti-Jaynes-Cummings-type Hamiltonians in cavity quantum electrodynamics. In the upper-bounded Hamiltonians, the atom-field interaction is confined to a subspace of Fock states ranging from Ι0> up to Ι4>, while in the sliced interaction the Fock subspace ranges from ΙM> up to ΙM + 4>. We also show how to build upper-bounded and sliced Liouvillians irrespective of engineering Hamiltonians. The upper-bounded and sliced Hamiltonians and Liouvillians can be used, among other applications, to generate steady Fock states of a cavity mode and for the implementation of a quantum-scissors device for optical state truncation. Finally we propose a scheme for the preparation of steady entanglements in bosonic dissipative networks. We describe its implementation in a system of coupled cavities interacting with an engineered reservoir built up of three-level atoms. Emblematic bipartite (Bell and NOON) and multipartite (W -class) states can be produced with high fidelity and purity.

Neste trabalho, descrevemos vários protocolos para a geração de estados estacionários não clássicos, suportados principalmente pela engenharia de hamiltonianos seletivos Jaynes-Cummings, e de reservatórios atômicos. Começamos apresentando um protocolo para engenhar interações seletivas lineares e não lineares do tipo Jaynes-Cummings como também simulações numéricas para comprovar a eficácia de nosso esquema. Analisamos também como aplicar essas interações seletivas à preparação e proteção de estados de Fock estacionários via reservatório atômico. Esta estratégia combina a ação dos mecanismo de amortecimento da cavidade com os de um reservatório atômico engenhado para conduzir uma distribuição térmica inicial a um estado de Fock estacionário. A mesma técnica pode ser utilizada para fatiar as distribuições de probabilidade no espaço de Fock, permitindo assim a preparação de uma variedade de estados de equilíbrio não clássicos. Também apresentamos um protocolo para a engenharia de interações upper-bound e sliced Jaynes-Cummings e anti-Jaynes-Cummings na eletrodinâmica quântica de cavidade. No Hamiltoniano upper-bound, a interação átomo-campo está confinada a um subespaço de Fock com estados que vão desde Ι0> até Ι4> enquanto que no Hamiltoniano sliced vão desde ΙM> até ΙM + 4>. Mostramos como construir Liouvillianos upper-bound independentemente da engenharia do Hamiltoniano upper-bound. Os Hamiltonianos e Liouvillianos upper-bound e sliced podem ser usados, entre outras aplicações, para gerar estados de Fock estacionários no modo da cavidade e para a implementação de um dispositivo de tesoura quântica para truncagem de estado óptico. Finalmente, propomos um esquema para a preparação de estados emaranhados estacionários em redes bosônicas dissipativas. Descrevemos a sua aplicação em um sistema de cavidades acopladas interagindo com um reservatório construído por átomos de três níveis. Os emblemáticos estados Bell e NOON, e estados multipartites (tipo W) podem ser produzidos com alta fidelidade e pureza. / In this work, we describe various protocols for the generation of nonclassical steady-state, supported mainly by the engineering selective Hamiltonian Jaynes-Cummings-type, and atomics reservoirs. We started presenting a framework to engineer nonlinear selective JaynesCummings-type interactions with numerical simulations to prove the effectiveness of our scheme. We further analyses how to apply these selective interactions to the preparation and protection of steady Fock states via atomic reservoir. This strategy combines the action of cavity damping mechanisms with that of an engineered atomic reservoir to drive an initial thermal distribution to a Fock equilibrium state. The same technique can be used to slice probability distributions in the Fock space, thus allowing the preparation of a variety of non-classical equilibrium states. Also we present a protocol to engineer upper-bound and sliced Jaynes-Cummings-type and anti-Jaynes-Cummings-type Hamiltonians in cavity quantum electrodynamics. In the upper-bounded Hamiltonians, the atom-field interaction is confined to a subspace of Fock states ranging from Ι0> up to Ι4>, while in the sliced interaction the Fock subspace ranges from ΙM> up to ΙM + 4>. We also show how to build upper-bounded and sliced Liouvillians irrespective of engineering Hamiltonians. The upper-bounded and sliced Hamiltonians and Liouvillians can be used, among other applications, to generate steady Fock states of a cavity mode and for the implementation of a quantum-scissors device for optical state truncation. Finally we propose a scheme for the preparation of steady entanglements in bosonic dissipative networks. We describe its implementation in a system of coupled cavities interacting with an engineered reservoir built up of three-level atoms. Emblematic bipartite (Bell and NOON) and multipartite (W -class) states can be produced with high fidelity and purity.

This thesis is about participation in IT design. The problem background that I have outlined is that information technologies have far reaching consequences for societies and for individuals, and that the design of information technologies is one among many practices that shape the world in which we live. From a democratic point of view it is crucial that also women should be involved in these reality producing practices. In relation to this there are at least two stories about women’s participation in IT design; one about their absence from IT design, and one about their inclusion therein. Based on this problem background the purpose of my research is to critically explore participatory IT design practices, with a special focus on gender, power and knowledge. In order to fulfil the purpose I have three research questions: Who participated in the IT design practices? How did knowledge come into being in these practices? How was responsibility enacted? My frame of reference is based on two research fields. One is Participatory Design (PD) with its focus on practitioners as co-designers in IT design practices, and the other is feminist technoscience which focuses on theories, methods, approaches, knowledge processes, and gender in technoscience practices. These two frameworks shares an interest in power relations and democratic participation in IT design. My empirical material was gathered with the help of ethnographic methods, and comes from a large IT design project in a Swedish government agency. The project was an eGovernment project, and a central objective was to rationalise the business. My focus was some (women) administrative officers who participated as business process analysts. This material was analysed with the help of feminist technoscience methodologies, foremost agential realism and diffraction. My thesis is based on five research papers, and the results of these are discussed and related to the research questions and the purpose. Based on an expanded notion of IT design and of participation in IT design, I argue that the administrative officers in the IT design project participated as central actors in the project. These administrative officers were able to participate within the context provided by various entangled sociomaterial practices, such as the project method, boundaries between business and IT, gendered divisions of labour, eGovernment, rationalisation, the project objectives, and an innovation practice. I also argue that in the project knowledge did not simply exist, but came into being as a result of entanglements of these sociomaterial practices, foremost the project objectives and the method. As a result of the reconfigured knowledge the administrative officers were removed to the periphery of the project. An additional argument is that with participation comes responsibility, and that responsibility is related to agency. Responsibility was enacted in and as a result of entangled sociomaterial practices. In this project the administrative officers were given and took a lot of responsibility within the boundaries provided by the sociomaterial practices, but they also worked to widen their agency and thus extend their responsibilities in the project. In relation to gender my argument is that the administrative officers in the project – who were women – participated as central actors, but they were also marginalised and made invisible. Thus in this IT design project women were included as central actors. As one of my contributions to PD and to feminist technoscience I want to underscore the importance of sociomaterial practices in IT design, such as IT design methods, and project objectives. These may act to restrict actors’ possibilities to act and to exert influence. Another is that knowledge in IT design practices come into being and are reconfigured as a consequence of intra-acting sociomaterial practices. Reconfigurations of knowledge might shift the power balance among actors in IT design projects and marginalise previously central actors. Responsibility too comes into being, or is enacted, in entangled sociomaterial practices. Furthermore responsibility in IT design is closely related to agency and participation, and widened agency might lead to extended possibilities to take responsibility. Additionally if positions in IT design are understood as fixed, they might make invisible more shifting and intricate professional relations and activities, and once these become visible, more women may become visible as central actors in IT design. A further contribution is that an expanded notion of IT design and participation might make women visible as central participants in IT design and in eGovernment. However, also central participants may become marginalised, as happened in this project.

This ethnographic study was conducted among the riverine people, also known as Ribeirinhos, in the state of Amazonas, Brazil, during four months of field research. The study focused on learning from Ribeirinhos’ experiences and practices of malaria. In this thesis, I argue that paying attention to Ribeirinhos’ experiences and diagnostic, treatment, and control practices of malaria can provide useful insights into blind spots in the current interventions to control the disease in Brazil. As this is a thesis by publications, the findings are presented in three manuscripts. The first manuscript focuses on how malaria is experienced by Ribeirinhos. It explores the embodiment of malaria, empirical strategies to distinguish it from other febrile sicknesses, misalignment between bodies and current biomedical diagnosis methods, “becomings” of bodies and experiences, and the vicissitudes of having the disease. The second manuscript examines experiences and treatment practices for vivax malaria highlighting the uses of pharmaceuticals, side effects of antimalarial drugs, and traditional treatments for malaria. The third manuscript describes Ribeirinhos’ perceptions of malaria-carrying mosquitoes, their everyday practices to manage these beings, and their experiences with control interventions, such as time monitoring recommendations (TMR), indoor residual spraying (IRS), and insecticide-treated nets (ITN). The three manuscripts clearly show that Ribeirinhos' lives are thoroughly entangled with Amazonian rivers and forests; malaria also takes part in these entanglements. Learning from their experiences and practices of malaria has provided information about the nuances, improvisations, and continuous negotiations required to coexist with the parasite and disease vectors.

The purpose and aim of this study is to offer a hitherto lacking perspective on the Sulu Archipelago’s history during the early years of American colonial rule – that of the native Sulu Sultan. Existing research, albeit new, tends to favour a U.S centred view. With concurrences as a theoretical framework and a theoretical understanding of the social and political power dynamics in the Sultanate, this study aims to challenge that perspective by examining the last Sultan of Sulu, Jamalul Kiram II’s agency and room for manoeuvre in relation to the bilateral Kiram-Bates treaty between the Sultanate of Sulu in the southern Philippines and the United States, represented by Colonel John C. Bates. Through a qualitative analysis of letters, official documents and a memoire originating from, or regarding, the time period, this study indicates that the Sultan’s agency and room for manoeuvre in relation to the Kiram-Bates treaty has been overlooked by scholars, and his position somewhat poorly understood. The Sultan did not simply sign the treaty according to American wishes. He negotiated terms, and influenced the outcome of above all the signing, and he at least reacted to and navigated the abrogation of the agreement in a way that has not been sufficiently described before. These findings prompt further research from a concurrences perspective to more thoroughly understand the history, and perhaps even the contemporary state, of the Sulu Archipelago and the Sulu Sultanate.

Fairy tales are enchanting geographical stories, which affectively organize space-time in socially, politically, and ethically significant ways. Despite this, fairy tales have been neglected in the discipline of geography, and the inter-discipline of fairy tale studies has rarely interrogated the spatialities of tales, or of storytelling more widely. This thesis addresses this lacuna by theorizing the relationship between fairy tales, storytelling, and geography through the subversive folkloric figures of the trickster and crone. It posits, first, that we understand fairy tales as iterative stories that constitute mythic communities; and second, that trickster and crone figures are enchanting territorializing and deterritorializing refrains that subvert this mythic community. These two concerns are explored through Nolan’s (2008) Batman film The Dark Knight, and Maitland’s (2009) short story Moss Witch. An experimental research approach provides insight into these ‘worldly,’ enchanting, and symbolically rich stories, without sacrificing their liveliness or ‘systematizing’ them for ideological gain. The research begins with an interpretive textual analysis to address the symbolic traditions of the fairy tale refrains. Collage enables a ‘retelling’ of the stories as materially and visually expressive media. Genealogical analysis traces the material-discursive matterings of the geographical refrains within academic ‘storytelling.’ These combined approaches ‘story’ the trickster and crone as spatial patterns with affective force. Trickster refrains are animating forces of destruction and chaos. They shift between the centre and periphery of mythic community, violently overturn its seemingly ordered realities, and unfold insecure and profane in-between places, where (human) community can no longer be sustained. The crone refrain enacts a ‘wilding’ in fairy tales, entangling the civilized, storied human polis (or culture more generally) with the nonhuman ‘environment,’ and undermining both relational accounts of being and more romantic discourses of dwelling. Going forward, continued engagement with this nexus of geography, storytelling, and fairy tales promises to enrich our multidisciplinary endeavours, highlight our theoretical ‘matterings’ of fairy tales, and enable more responsible engagement with these endlessly enchanting stories.

En dépit de leur importance pratique considérable, et bien que de nombreuses expériences établissent une corrélation certaine entre les hétérogénéités d’interaction de surface (rugosité ou inhomogénéités chimiques) et les propriétés de friction des surfaces, le rôle de ces interactions sur la friction n’est encore pas bien décrit par les modèles et les expériences existants. Dans ce travail de thèse, nous nous sommes intéressés à l’identification des mécanismes moléculaires de la friction aux interfaces polymères souples. Dans ce contexte, nous avons réalisé deux études complémentaires. La première partie du travail concerne le mouvement d’une ligne triple solide-liquide-vapeur qui se déplace sur une surface solide sous l’effet de différentes forces (gravité, forces capillaires et tensions interfaciales), et en particulier le lien entre le piégeage et le dépiégeage de la ligne triple et l’hystérèse de l’angle de contact. Cette méthode permet de mesurer des angles de contact d’avancée et de reculée avec une précision sans précédent (0,1°)et s’avère être particulièrement sensible aux mécanismes qui tendent à ancrer la ligne triple. Ceci en fait un outil de choix pour étudier la friction liquide/solide. Dans la seconde partie du travail, nous avons cherché à comprendre comment des chaînes de polymère flexibles, fortement ancrées sur une surface solide, dans le régime des fortes densités de greffage affectent la friction entre une telle surface et un élastomère réticulé constitué du même polymère. Nous avons montré que le comportement en friction de cette couche confinée suit exactement le comportement rhéofluidifiant observé pour des couches de fondu de masses molaires équivalentes mais avec un temps de relaxation beaucoup plus long que celui des chaînes en fondu,la reptation n’étant pas permise pour les chaînes ancrées. Enfin, en comparant les résultats obtenus pour des couches greffées chimiquement à une extrémité et des couches fortement adsorbées, ayant par ailleurs les mêmes caractéristiques moléculaires (masse molaire des chaînes et épaisseur de la couche ancrée), nous avons mis en évidence que la friction est remarquablement sensible à l’organisation moléculaire au sein de la couche ancrée. / Different experiments show a correlation between interaction heterogeneities (roughnessor chemical inhomogeneities) and friction properties of surfaces but the exact role of theseinteractions is still not clearly established. In this thesis, we try to identify molecular mechanism offriction at soft polymer interfaces. In this context, we have performed two complementary studies.The first one concerns the movement of a triple line solid-liquid-gas which moves on a solidsubstrate and more particularly the link between trapping and entrapping of the triple line andcontact angle hysteresis. This method allows measurement of dynamic contact angles with a verygood precision (0,1°), and is particularly sensitive to mechanisms which tend to anchor a tripleline. This technique is then a very efficient tool to study solid/liquid friction.In the second part of this thesis, we try to understand how flexible polymer chains stronglyanchored on a solid substrate affect friction at the interface between such surface and crosslinkedelastomer made of the same polymer. We show that the friction is dominated by the shearthinning of the grafted layer confined between the elastomer and the substrate, and responding tothe shear solicitation like a melt, with very long relaxation times. We also show that the frictionstress appears highly sensitive to the molecular organization inside the surface anchored polymerlayer, comparing end grafted and strongly adsorbed layers having otherwise the same molecularcharacteristics (molecular weight of the chains, and thickness of the surface anchored layer).

The mechanical and physical properties of polymers are determined primarily by the underlying nano-scale structures and characteristics such as entanglements, crystallites, and molecular orientation. These structures evolve in complex manners during the processing of polymers into useful articles. Limitations of available and foreseeable computational capabilities prevent the direct determination of macroscopic properties directly from atomistic computations. As a result, computational tools and methods to bridge the length and time scale gaps between atomistic and continuum models are required. In this research, an internal state variable continuum model has been developed whose internal state variables (ISVs) and evolution equations are related to the nano-scale structures. Specifically, the ISVs represent entanglement number density, crystal number density, percent crystallinity, and crystalline and amorphous orientation distributions. Atomistic models and methods have been developed to investigate these structures, particularly the evolution of entanglements during thermo-mechanical deformations. A new method has been created to generate atomistic initial conformations of the polymer systems to be studied. The use of the hyperdynamics method to accelerate molecular dynamics simulations was found to not be able to investigate processes orders of magnitude slower that are typically measurable with traditional molecular dynamics simulations of polymer systems. Molecular dynamics simulations were performed on these polymer systems to determine the evolution of entanglements during uniaxial deformation at various strain rates, temperatures, and molecular weights. Two methods were evaluated. In the first method, the forces between bonded atoms along the backbone are used to qualitatively determine entanglement density. The second method utilizes rubber elasticity theory to quantitatively determine entanglement evolution. The results of the second method are used to gain a clearer understanding of the mechanisms involved to enhance the physical basis of the evolution equations in the continuum model and to derive the models material parameters. The end result is a continuum model that incorporates the atomistic structure and behavior of the polymer and accurately represents experimental evidence of mechanical behavior and the evolution of crystallinity and orientation.