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Immersed boundary (IB) methods are attractive due to their ability to simulate flow over complex geometries on a simple Cartesian mesh. Unlike conformal grid formulation, the mesh does not need to conform to the shape and orientation of the boundary. This eliminates the need for complex mesh and/or re-meshing in simulations with moving/morphing boundaries, which can be cumbersome and computationally expensive. However, the imposition of boundary conditions in IB methods is not straightforward and numerous modifications and refinements have been proposed and a number of variants of this approach now exist. In a nutshell, IB methods in the literature often suffer from numerical oscillations, implementation complexity, time-step restriction, burred interface, and lack of generality. This limits their ability to mimic conformal grid results and enforce Neumann boundary conditions. In addition, there is no generic IB capable of solving flow with multiple potentials, closely/loosely packed structures as well as IBs of infinitesimal thickness. This dissertation describes a novel 2$ ^{\text{nd}} $ order direct forcing immersed boundary method designed for simulation of two- and three-dimensional incompressible flow problems with complex immersed boundaries. In this formulation, each cell cut by the IB is reshaped to conform to the shape of the IB. IBs are modeled as a series of 2D planes in 3D space that connect seamlessly at the edges of the cut cells, in a way that mimics conformal grid. IBs are represented in a continuous and consistent fashion from one cell to another, thus eliminating spatial pressure oscillations originating from inconsistent description of the IB as well as the traditional stair-step problem, leading to a more accurate resolution of the boundary layer. Boundary conditions are enforced at the exact location of the IB devoid of interpolation, which guarantees sound simulations even on grids with high aspect ratio, and enables simulations of flow packed with multiple IBs in close proximity. Boundary conditions for each phase across the IB are enforced independently, yielding a unique capability to solve flows with zero-thickness IBs. Simulations of a large number of 2D and 3D test cases confirm the prowess of the devised immersed boundary method in solving flows over multiple loosely/closely-packed IBs; stationary, moving and highly morphing IBs; as well as IBs with zero-thickness. Extension of the proposed scheme to solve flow with multiple potentials is demonstrated by simulating transfer and transport of a passive scalar from an array of side-by-side and tandem cylinders in cross-flow. Aquatic vegetation represented by a colony of circular cylinders with low to high solid fraction is simulated to showcase the prowess of the current numerical technique in solving flow with closely packed structures. Aquatic vegetation studies are extended to a colony of flat plates with different orientations to show the capability of the developed method in modeling zero-thickness structures.

A growing interest for Cannabidiol (CBD), a component of Cannabis Sativa, has occurred over the past years. The medical potential of the component is yet to be better characterized, as its effects on sleep, and in particular memory, are to date not well understood or consistently characterized. This master thesis project focuses on analysing the effect of CBD on an anaesthesia-induced sleep-like state in rats, and its effects on the hippocampal sharp-wave-ripples, which have been shown to be associated with memory replay during sleep, and hence system consolidation. The hippocampus and prefrontal cortex, the two structures involved in memory consolidation, were recorded in 19 rats, split in two groups (CBD and vehicle). From these recordings, an automated sleep scorer using principal component analysis was developed to obtain the animals’ hypnograms, which were analysed to study sleep-like structure. From the recordings of the hippocampal pyramidal layer, and an additionnal layer deeper under it, respectively ripples and sharp waves were detected in all animals, and characterized for each group. We observed and demonstrated that CBD changes the sleep-like structure by shortening both REM and NREM bouts, resulting in an increase in transitions between both states. Additionally, we observed that, although ripples are not significantly different between both groups, sharp waves tend to be smaller among CBD animals. Lastly we noticed that both sharp wave and ripple activity, after increasing upon transition to NREM, decreases as the bout last. This finding suggests that vehicle animals, who have longer bouts and less transitions, would display less sharp wave and ripple activity, although we found no significant difference in the amount of both brain events. This paradox suggests that there is still more to characterize in order to understand if CBD enhances or not memory consolidation. In sum, CBD changes anaesthesia-induced sleep by shortening the duration of both NREM and REM bouts, resulting in an increase in transitions between both state. As for sleep events, sharp waves appeared shorter among CBD animals, although the same difference was not observed for ripples. Finally, sharp wave and ripple activity appear to peak upon transition from REM to NREM sleep, and decreases as the NREM bout lasts longer, however, no effect of CBD on this observation was highlighted.

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À l’origine de ce mémoire se trouve le souhait de saisir en profondeur ce que représente l’endoctrinement et de voir comment, si tel est le cas, la philosophie pour enfants de Matthew Lipman et Ann Margaret Sharp pourrait servir de rempart contre son existence. Pour ce faire, nous commençons par étudier la définition qu’en propose le philosophe de l’éducation, Olivier Reboul. À la lumière de son analyse, nous présentons deux cas concrets d’endoctrinement, l’éducation hitlérienne et la reproduction sociale par le biais du système scolaire français. Ces études de cas ont pour visée d’évaluer la définition proposée par Reboul et également de révéler l’importance de contrer l’endoctrinement. Partant de l’hypothèse que la pratique de la philosophie pour enfants, selon l’approche de M. Lipman et A. M. Sharp, peut être un rempart approprié pour contrer l’endoctrinement, nous présentons, dans la seconde partie de ce mémoire, le but, les objectifs et la méthode de cette pratique en éducation. Nous pouvons dès lors tenter de montrer de quelle manière elle permettrait de lutter efficacement contre l’endoctrinement en évitant d’être endoctriné ou d’avoir la tentation de le faire. / At the origin of this paper is the desire to gain an in-depth understanding of indoctrination, what it represents and to see how, if so, Matthew Lipman and Ann Margaret Sharp's approach to philosophy for children could serve as a rampart against its existence. To do this, we begin by studying the definition proposed by Olivier Reboul, a philosopher of education. In light of his analysis, we will present two concrete cases of indoctrination, education in Nazy Germany under the Hitler regime and social reproduction through the French school system. The purpose of these case studies is to evaluate Reboul’s definition and reveal the urgent need to counter indoctrination. Assuming that the practice of philosophy for children, according to M. Lipman and A. M. Sharp, may be an appropriate rampart to counter indoctrination, we present, in the second half of this paper, the purpose, objectives and method of this practice in education. We can therefore try to show how it could effectively combat indoctrination avoiding being indoctrinated or the temptation to indoctrinate.

Syfte. Att belysa attityder hos operationspersonal samt risken för intraoperativa stick- och skärskador. Bakgrund. Det finns flera olika tekniker för att hantera stickande och skärande instrument och olika säkerhetsprodukter som kan användas för att minimera risken för stick- och skärskador. Det finns många studier som handlar om lämpliga arbetssätt för att minimera risken för stick- och skärskador, men bara ett fåtal studier som belyser betydelsen av användarnas attityder och inställning till användande av tekniker och säkerhetsprodukter samt uppföljning och rapportering av tillbud. Metod. Studiens design är en empirisk intervjustudie med kvalitativ ansats. Semistrukturerade intervjuer utfördes med sju operationssjuksköterskor och fyra operatörer på två sjukhus i Sverige. Data insamlades oktober-december 2015. Resultat. Resultatet visar på att det finns olika attityder hos operationspersonal som kan påverka risken för stick- och skärskador, vilka redovisas under fyra olika teman: Att ha ett säkert arbetsklimat; Att skydda sig själv, medarbetare och patient; Att vara följsam till riktlinjer och arbetsrutiner samt Att vara oföljsam riktlinjer och arbetsrutiner. Slutsats. Risken för stick- och skärskador går inte att eliminera då det alltid finns riskområden som man som operationspersonal måste ta hänsyn till. Det finns mycket kunskap kring säkerhetsprodukter och tekniker som syftar till att minimera risken för stick- och skärskador men om användarens attityd får styra kanske inte dessa används på rätt sätt om ens alls. I denna studie framkommer det en antydan till att attityder hos operationspersonal kan påverka risken intraoperativa stick- och skärskador. / Aim. To illustrate the attitudes of the operating theatre personnel and the risk of intraoperative sharp injuries. Background. There are several ways to manage sharp instruments such as various techniques and safety products to minimize the risk of sharps injuries. There are many studies about working practices to minimize the risk of sharps injuries but only a few that illustrate the importance of attitudes towards techniques and safety products as well as follow up and reporting incidents. Method. The design of the study is an empirical interview study with a qualitative approach. Semi-structured interviews were conducted with seven theatre nurses and four surgeons at two hospitals in Sweden. Data collected October-December 2015. Findings. The findings show that there exists different attitudes of the operating theatre personnel that could affect the risk of sharps injuries. The finding is presented in four themes: To have a safe working environment; To protect oneself, co-worker and patient; To be compliant to guidelines and working practices and To be non-compliant to guidelines and working practices. Conclusions. The risk of sharp injuries can’t be eliminated since there is always a risk of sharp injuries which the operating theatre personnel must pay attention to. There are a lot of knowledge about safety products and techniques for minimizing the risk of sharps injuries but when the attitude of the user come into play the safety product may not be used correctly, if used at all. In this study a indication appears that the attitudes of the operating theatre personnel may be affecting the risk of intraoperative sharp injuries.

The photoactive component of a polymeric organic solar cell can be produced by drying a mixture consisting of a volatile solvent and non-volatile polymers. As the solvent evaporates, the polymers demix and self-assemble into microscale structures, the morphology of which plays a pivotal role in determining the efficiency of the resulting device. Thus, a detailed understanding of the physical mechanisms that drive and influence structure formation in evaporating solvent-polymer mixtures is of high scientific and industrial value. This thesis explores several problems that aim to produce novel insights into the dynamics of evaporating solvent-polymer mixtures. First, the role of compositional Marangoni instabilities in slowly evaporating binary mixtures is studied using the framework of linear stability theory. The analysis is non-trivial because evaporative mass loss naturally leads to a time-dependent base state. In the limit of slow evaporation compared to diffusion, a separation of time scales emerges in the linear stability problem, allowing asymptotic methods to be applied. In particular, an asymptotic solution to linear stability problems that have slowly evolving base states is derived. Using this solution, regions of parameter space where an oscillatory instability occurs are identified and used to formulate appropriate conditions for observing this phenomenon in future experiments. The second topic of this thesis is the use of multiphase fluid models to study the dynamics of evaporating solvent-polymer mixtures. A two-phase model is used to assess the role of compositional buoyancy and to examine the formation of a polymer-rich skin at the free surface. Then, a three-phase model is used to conduct a preliminary investigation of the link between evaporation and phase separation. Finally, this thesis explores the dynamics of a binary mixture that is confined between two horizontal walls using a diffusive phase-field model and its sharp-interface and thin-film approximations. We first determine the conditions under which a homogeneous mixture undergoes phase separation to form a metastable bilayer. We then present a novel mechanism for generating a repeating lateral sequence of alternating A-rich and B-rich domains from this bilayer.

Over the twentieth century, Camille Lucie Nickerson excelled in her multi-faceted career as an educator, musician, and interpreter for the advancement of musical education for generations of black students in New Orleans and at Howard University in Washington D.C. Nickerson devoted herself to furthering her musical education through private instruction with her father, Professor William J. Nickerson. She then graduated with a diploma from Southern University and with a B.A. and M.A. in music from Oberlin College. Nickerson’s leadership in musical associations on a local and national level enhanced her ability to reach audiences of all ages through her performances. She dedicated her life to musical education and the sharing Creole folk music, both personal attributes passed down from her father. While Nickerson was determined to preserve Creole folk music through her lecture-recitals, her wider purpose argued for a distinct recognition for Creole culture, thus, acknowledgment of her culture.