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Magnetic resonance imaging (MRI) is an imaging technique that is used in hospitals worldwide. The images are acquired through the use of an MRI scanner and the clinical information is provided through the image contrast, which is based on the magnetic properties in biological tissue. By altering the scanner settings, images with different contrast properties can be obtained. Conventional MRI is a qualitative imaging technique and no absolute measurements are performed. At Center for Medical Imaging and Visualization (CMIV) researchers are developing a new MRI technique named synthetic MRI (SyMRI). SyMRI is based on quantitative measurements of data and absolute values of the magnetic properties of the biological tissue can be obtained. The purpose of this master thesis has been to take the development of SyMRI a step further by developing and implementing a visualization studio for SyMRI imaging of the human brain. The software, SyMRI Brain Studio, is intended to be used in clinical routine. Input from radiologists was used to evaluate the imaging technique and the software. Additionally, the requirements of the radiologists were converted into technical specifications for the imaging technique and SyMRI Brain Studio. Additionally, validation of the potential in terms of replacing conventional MRI with SyMRI Brain Studio was performed. The work resulted in visualization software that provides a solid formation for the future development of SyMRI Brain Studio into a clinical tool that can be used for validation and research purposes. A list of suggestions for the future developments is also presented. Future clinical evaluation, technical improvements and research are required in order to estimate the potential of SyMRI and to introduce the technique as a generally used clinical tool.

This thesis describes the work of three research projects, the background research that motivated the work, and the resultant project findings. The three projects concerned: (i) Geometric stochastic resonance in a double cavity, (ii) Synchronisation of geometric stochastic resonance by a bi-harmonic drive, and (iii) Rectification of Brownian particles with oscillating radii in asymmetric corrugated channels. In the project 'Geometric stochastic resonance in a double cavity', we investigated synchronisation processes for the geometric stochastic resonance of particles diffusing across a porous membrane and subject to a periodic driving force. Non-interacting particle currents were driven through a symmetric membrane pore either parallel or perpendicular to the membrane. Then, harmonic mixing spectral current components were generated by the combined action of parallel and perpendicular drives. The role of the repulsive interaction of particles as a controlling factor with potential applications to the transport of colloids and biological molecules through narrow pores was also investigated. In 'Synchronisation of geometric stochastic resonance by a bi-harmonic drive', we simulated the stochastic dynamics of an elliptical particle using the Langevin equation. The particle was simultaneously driven by low and high frequency harmonic drives across a porous inter-cavity membrane. It was observed that the particle oscillated out of phase with the low frequency drive. This effect was due to the absolute negative mobility the particle would have exhibited if the low frequency drive had been replaced by a dc static force. It was also observed that the magnitude of this out-of-phase stochastic resonance depends on how the combined action of the driving forces and noise fluctuations affect the particle orientation, and as such was shown to be sensitive to the particle shape. This emphasises the importance of particle geometry, in addition to chamber geometry, to the realisation and optimisation of geometric stochastic resonance. In the project 'Rectification of Brownian particles with oscillating radii in asymmetric corrugated channels', we simulated the transport of a Brownian particle with an oscillating radius freely diffusing in an asymmetric corrugated channel over a range of driving forces for a series of temperatures and angular frequencies of radial oscillation. It was observed that there was a strong influence of self-oscillation frequency upon the average particle velocity. This effect can be used to control rectification of biologically active particles as well as for their separation according to their activity, for instance in the separation of living and dead cells. The background research is described in Chapter One and the research findings are described along with their related projects in Chapters Two and Three.

Master of Science / Department of Chemistry / Mark D. Hollingsworth / Most urea inclusion compounds (UICs) are known to share a common packing arrangement in which the urea host forms helical ribbons held together by hydrogen bonds to form a series of linear, hexagonal tunnels. Because UICs can encapsulate a wide variety of linear guest molecules, they serve as useful model systems for probing mechanisms of crystal growth and molecular recognition. In this thesis, the syntheses (or attempts thereof) of six compounds that will serve as consequential guest molecules in studies of UICs are presented. These compounds are (5S,6S)-2,9-decanedione-d2, 1,6-dicyanohexane-1,1,6,6-d4, 1,11-undecanedioic acid, bis(3-oxobutyl) adipate, 2,16-heptadecanedione, and 2-eicosanone. With the exception of (5S,6S)-2,9-decanedione-d2, whose synthesis remains incomplete, detailed synthesis and crystal growth of the UICs of these compounds are discussed. Ongoing studies with the UICs containing these guests include the determination of the absolute configuration of UICs, the study of guest conformer population changes via solid-state NMR, the development and identification of novel ferroelastic UICs, and the classification of guest ordering in a series of alkanedione UICs.

A filosofia, para Hegel, é o saber conceitual que se pensa e pensa sua época, sendo esse saber resultado do processo de desenvolvimento histórico e cultural do mundo. Nesse sentido, a Fenomenologia do Espírito é a apresentação necessária do movimento de formação do saber que surgiu na época de Hegel, o qual ele denomina de saber absoluto. Esse é o resultado do percurso que culminou na Revolução Francesa, na religião protestante e na filosofia do idealismo transcendental, e a Fenomenologia apresenta esse encadeamento através de suas figuras, isto é, momentos da história, da cultura e da filosofia tomados a partir de sua perspectiva conceitual e conectados de forma a demonstrar as transformações do saber ele mesmo. A partir disso, Hegel denomina o saber absoluto como última figura do espírito, que, como ele aponta no final da obra, também é a nova figura, a filosofia como ciência, e se propõe a desenvolvê-la naquilo que ele chama de Ciência da Lógica. Desse modo, o objetivo desse ou, em outras palavras, se é possível, a partir do próprio sistema hegeliano, considerar o surgimento de novas figuras do espírito depois da figura do saber absoluto ou da filosofia do idealismo absoluto. Para isso, busca-se esclarecer a noção de figura na Fenomenologia, bem como suas condições de possibilidade e aquilo que Hegel utiliza como o seu método científico, a saber, o processo dialético, explicitado na noção de suprassunção (Aufhebung). A fim de esclarecer essas noções de modo mais preciso, recorre-se a noções da Ciência da Lógica e retorna-se à Fenomenologia a partir deles, de modo a compreendê-los de maneira concreta e de salientar os aspectos lógicos já presentes nessa obra. Para isso, procurase demonstrar aqui que a Lógica hegeliana não é apenas uma ciência formal, como a metafísica tradicional usualmente considera, mas também uma ontologia, um estudo de como o ser é. Para Hegel, o ser é o conceito e por isso se pode ter um saber conceitual, como o saber absoluto, acerca da realidade e ele ser um saber efetivo, isto é, um conhecimento das coisas como elas são nelas mesmas, e não apenas como elas aparecem para nós segundo nossas condições de possibilidade da experiência, como tenta mostrar o idealismo transcendental de Kant. Por isso, este trabalho defende que a ontologia hegeliana não é nem um retorno à metafísica tradicional, nem uma radicalização dessa, mas uma apropriação de seus conceitos revistos sob a óptica das novas lentes do saber absoluto, um saber qualitativamente diferente dos saberes anteriores e que, precisamente por isso, permitiria a continuação e atualização desse saber de acordo com novos momentos históricos e culturais. / For Hegel, philosophy is the conceptual knowing that is thought about and thinks about its time. This knowing derives from the process of historical and cultural development of the world. Thus, the Phenomenology of Spirit is the necessary presentation of the movement of knowledge acquisition that arose in Hegel's time, which he calls absolute knowing. This is the result of the path that climaxed in the French Revolution, in the Protestant religion and in the philosophy of transcendental idealism. The Phenomenology presents this chaining through its figures, that is, moments of history, of culture and of philosophy taken from their conceptual perspective and connected in order to demonstrate the transformations of knowing itself. Based on this, Hegel considers absolute knowing the last figure of spirit, which, as he points out at the end of the work, is also the new figure, philosophy as science, and proposes to develop it in what he calls the Science of Logic. Therefore, this study aims to investigate in what sense one can understand the determination of figure of or, in other words, if it is possible, based on the Hegelian system itself, to consider the emergence of new figures of spirit after the figure of absolute knowing or of the philosophy of absolute idealism. In order to do so, it seeks to clarify the notion of figure in the Phenomenology, as well as its conditions of possibility and what Hegel uses as his scientific method, namely, the dialectical process, explicit in the notion of sublation. In order to more precisely clarify these notions, notions from the Science of Logic are used and a return to the Phenomenology is made based on them, so as to understand them in a concrete way and to emphasize the logical aspects already present in this work. To this end, here we try to demonstrate that the Hegelian Logic is not only a formal science, as traditional metaphysics usually considers it to be, but also an ontology, a study of how the being is. For Hegel, the being is the concept and therefore it is possible to have a conceptual knowing, such as the absolute knowing, about reality, and it can be an actual knowing, that is, a knowledge of things as they are in themselves and not only as they appear to us according to our conditions of possibility of experience, as transcendental idealism attempts to show us. Therefore, this study argues that the Hegelian ontology is neither a return to traditional metaphysics nor a radicalization of this metaphysics, but an appropriation of its concepts revised under the new lenses of absolute knowing, a knowing that is qualitatively different from previous types of knowing and that, precisely for this reason, would allow the continuation and updating of this knowing according to new historical and cultural moments.

The use of environmental geometry as a spatial cue is well established for a range of species. Previous research has focused largely on the use of global geometry (e.g., the shape of a room). Thus, comparatively less is known about how local geometry (e.g., corner angles within a room) is encoded. The purpose of the research presented in this thesis was to examine how angular information is encoded and to determine whether angle size influences encoding, using a discrimination task and a spatial array task. Chapter 2 presents a study during which pigeons were trained to discriminate between a small (60°) and large (120°) angle. Once the birds were accurately choosing the angle associated with reward, they were tested on their ability to discriminate between their training angle and one of a series of novel angles. The pigeons showed an absolute learning pattern for the small training angle, but not the large angle. The significance of this result is that the small angle may have been perceived as more distinctive compared to the large angle. Adopting a comparative approach, Chapter 3 presents a study during which adult humans were trained and tested using a similar paradigm but with different training angles (25°, 50° and 75°). The results of this study also support an absolute learning pattern for the small training angle but not the large. These results are significant in that they suggest that angle size may be an important local geometric cue that is encoded in a similar way by both pigeons and humans. To understand how angular information may be processed during a spatial task, Chapter 4 presents a study during which adult humans were trained and tested on their ability to use local angles (either 50° or 75°) to find a goal location within an object array. The results showed that the smaller angle was used more effectively as a spatial cue than the larger angle. Overall, these results are important as they suggest that small and large angles are encoded differently by pigeons and humans, with small angles perceived as more distinctive than large angles.

The use of environmental geometry as a spatial cue is well established for a range of species. Previous research has focused largely on the use of global geometry (e.g., the shape of a room). Thus, comparatively less is known about how local geometry (e.g., corner angles within a room) is encoded. The purpose of the research presented in this thesis was to examine how angular information is encoded and to determine whether angle size influences encoding, using a discrimination task and a spatial array task. Chapter 2 presents a study during which pigeons were trained to discriminate between a small (60°) and large (120°) angle. Once the birds were accurately choosing the angle associated with reward, they were tested on their ability to discriminate between their training angle and one of a series of novel angles. The pigeons showed an absolute learning pattern for the small training angle, but not the large angle. The significance of this result is that the small angle may have been perceived as more distinctive compared to the large angle. Adopting a comparative approach, Chapter 3 presents a study during which adult humans were trained and tested using a similar paradigm but with different training angles (25°, 50° and 75°). The results of this study also support an absolute learning pattern for the small training angle but not the large. These results are significant in that they suggest that angle size may be an important local geometric cue that is encoded in a similar way by both pigeons and humans. To understand how angular information may be processed during a spatial task, Chapter 4 presents a study during which adult humans were trained and tested on their ability to use local angles (either 50° or 75°) to find a goal location within an object array. The results showed that the smaller angle was used more effectively as a spatial cue than the larger angle. Overall, these results are important as they suggest that small and large angles are encoded differently by pigeons and humans, with small angles perceived as more distinctive than large angles.

This study investigates investment behavior of Taiwan market participants from different aspects of measure, especially with regard to their tendency to forming herding behavior. By applying concepts of Cross-Sectional Absolute Dispersions (CSAD), we find significant evidence of herding behavior in the Taiwan market. Evidences suggest that the herding formation in Taiwan market is strongly influenced by the US market and we should not ignore the impact of globalization. With regard to the issue of financial crises, we find no herding behavior during the 1998 Asian Crisis but partial evidence shows that herding activities may be influenced by crisis during the 2000 Internet Bubble and 2008 Sub-prime Crisis in the Taiwan market. Moreover, all empirical results are reexamined using Quantile analysis to avoid potential bias in estimations. Finally, results from applying herding behavior in portfolio management indicate that investing in stocks of lower liquidity and volatility can reduce the risk of portfolios.

Magnetic resonance spectroscopy has been widely used in medical applications, rendering precise evaluation and diagnosis in clinics. As the development of various tools for automatic spectra analysis, providing objective quantification of metabolites, absolute concentrations has been playing an important role in clinical studies and applications as well. In this study, we investigate the reliability and accuracy of absolute concentration quantified by LCModel. Ten healthy subjects were included. We compared the resultant concentrations calculated by internal water scaling and phantom calibration, both of which are provided by LCModel. Partial volume effect was also taken into account to improve the accuracy of absolute concentrations. Automatic segmentation was applied to volume of interest in order to separate gray matter and white matter, which will facilitate the further partial volume correction and thus better accuracy of absolute quantification.

Magnetic resonance spectroscopy is now in widespread use, which with various tools of spectra analysis can provide concentrations of metabolites. The influence of metabolites on human physiology is greatly. Due to the tiny variation of the concentration in various metabolites, the analytic method used in the quantitative determination of the absolute concentrations of metabolites plays an important role in this research area. In this thesis we present an analysis tool for segmentation of white matter, gray matte and cerebrospinal fluid using region growing with spatial space, and provide manual interaction for exception handling in this subject. Then we use this tool to analyze different percentages of white matter and gray matter with the default parameter by LCModel and correct partial volume effect. The results show that the proposed tool can improve significantly the accuracy in absolute quantitative analysis of concentration.