In this work a review of many of the current theories of star formation as it is understood today is presented. New polarimetric observations of three cometary nebulae, RMon/NGC2261, RCr A/NGC6729 and the Chamaeleon Infrared Nebula are presented and discussed. It is shown how previous polarimetric measurements of the illuminating source of Hubble's variable nebula (NGC2261) have often produced results which increase in error with increasing wavelength. The reason for this is that previous authors have used an aperture size for measurements of R Mon which includes effects of a highly polarized feature ~ 5" north of RMon. Though this phenomenon has been seen before by other observers, its effect on polarimetric measurements of R Mon has not been recognised before despite tests to check for this. The data presented here agree with the interpretation that this feature is the northern-lobe of a mini-bipolar nebula, and it is further suggested that this is a manifestation of episodic mass outflow from R Mon. Previous explanations for the polarization of R Mon and RCr A cannot explain the rapid change in polarization and position angle that these young stellar objects are seen to undergo. Models of these objects which assume that they appear as polarized sources are used to explain the polarizations and are discussed. These models are not only able to produce the level of polarization seen at the source, but they are also currently the best models for explaining the rapid changes in polarization that are observed. A jet-like feature is seen to the south-west of the main nebulosity in the Chamaeleon IRN for the first time in observations presented in this thesis. A similar jet seen emerging from RCr A has been explained as being an emission feature collimated by an inner-circumstellar disc by previous authors. Evidence presented in this work for the jets seen emanating from both RCr A and the Chamaeleon IRN, suggests that these features are merely the preferentially illuminated rims of one of the outflow cavities, seen mainly by reflection of light from the source. Further evidence is provided to show that NGC2261 and NGC6729 are illuminated by RMon and RCr A respectively. In the case of the Chamaeleon IRN new evidence is provided to show that the nebula is illuminated by a heavily obscured infrared source located midway between the two outflow cavities.

The various aspects of a social science ramify closely with one another, and so it will be necessary to inspect certain economic theories rather extensively in search of their meaningful connection with the word "capital." However, the major purpose here will be an examination of the use and potential logical use of the terms "capital" and "capital formation."

Some equations of linear elasticity are developed, including those specific to certain actuator structures considered in formation theory. The invariance of the strain-energy under the transformation from rectangular to spherical coordinates is then established for use in two specific formation problems. The first problem, involving an elastic structure with a cylindrical equilibrium configuration, is formulated in two dimensions using polar coordinates. It is shown that L² controls suffice to obtain boundary displacements in H^1/2. The second problem has a spherical equilibrium configuration and utilizes the elastic equations in spherical coordinates. Results similar to those obtained in the two dimensional case are indicated for the three dimensional problem. / Ph. D.

Tomography in soft X-ray microscopy is an emerging technique for obtaining quantitative 3D structural information about cells. One of its strengths, compared with other techniques, is that it can image intact cells in their near-native state at a few 10 nm’s resolution, without staining. However, the methods for reconstructing 3D-data rely on algorithms that assume projection data, which the images are generally not due to the imaging systems’ limited depth of focus. To bring out the full potential of tomography in soft X-ray microscopy an improved understanding of the image formation is desired. This Thesis reviews zone plate-based X-ray microscopy for biological imaging and the theory necessary for a numerical implementation of a 3D image formation model. Furthermore, a novel reconstruction approach is proposed that improves the overall resolution in a reconstruction of a tomographically imaged object. This is demonstrated by simulations and experiments. Finally, this Thesis covers work on the Stockholm X-ray microscope, including an upgrade of the X-ray source yielding unprecedented brightness for a compact system. With this upgrade it was possible to do high-quality imaging of cells in their near-native state with only 10 second exposures. / Tomografi i mjukröntgenmikroskopi är en ny teknik för att få ut kvantitativ strukturell 3D information om celler. Dess styrka jämfört med andra tekniker är att den kan avbilda intakta celler i deras nära naturliga tillstånd med ett par 10 nm upplösning, utan omfattande preparering. Dock är metoderna för att rekonstruera 3D-data beroende av algoritmer som antar projektionsdata, vilket bilderna i allmänhet inte är på grund av avbildningsystemens begränsade skärpedjup. För att få ut den fulla potentialen av tomografi i röntgenmikroskopi behövs en ökad förståelse för avbildningsprocessen. Denna avhandling behandlar zonplatte-baserad röntgenmikroskopi för biologisk avbildning och den nödvändiga teorin för en numerisk implementering av en avbildningsmodell i 3D. En ny rekonstruktionsmetod föreslås som förbättrar upplösningen i rekonstruktionen för ett tomografiskt avbildat objekt. Detta visas i simuleringar och experiment. Slutligen omfattar denna avhandling arbete på Stockholms mjukröntgenmikroskop, inklusive en uppgradering av röntgenkällan som ger oöverträffad ljusstyrka för ett kompakt system. Denna uppgradering möjliggör högkvalitativ avbildning av celler i deras nästan naturliga tillstånd med endast 10 sekunders exponering. / <p>QC 20160324</p>

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This thesis examines the effects of economic and political turbulence on coalition-formation across 37 EU and OECD democracies. Utilizing the existing potential-coalitions research, it analyzes how increases in turbulence affect common variables predicted to determine which coalitions are chosen of all potential cabinets following an election. These variables drawn from the coalition-formation field are examined using a conditional logit regression model with interaction effects, and results indicate that both political and economic turbulence highly affect the way coalition formation is carried out, although the effects of the two turbulence types vary. During economic turbulence larger coalitions appear to be warranted, although results simultaneously suggest that ideological cohesion is hard to achieve during turbulent times. During political turbulence, instead, results suggest ideologically wide coalitions are more common but that minority cabinets are still more likely to appear. Despite the varying results, this analysis finds support that coalition formation is greatly affected by both economic and political turbulence. While the effects of some coalition-formation variables utilized by previous researchers appear to withstand the addition of turbulence, other effects change greatly when levels of instability are considered.

The aim of the thesis is to examine contemporary constructions of mixed race in the United States and Britain through the examination of two types of racial projects: the national census and voluntary and community organisations focused on mixed race. Using a combination of critical discourse analysis and qualitative interviews, the research analyses the ways in which mixed race is being described, conceptualised, and constructed through macro- and meso-level racial projects in each nation, in order to compare the racial formation processes that are occurring in the early twenty-first century's "mixed race moment". The thesis builds upon racial formation theory, which argues that the concept of "race" is never fully fixed, but rather is made through socio-historical processes that create, inhabit, transform, and destroy racialised notions over time and context (Omi and Winant 1986, 1994, 2015). The theory examines the struggles over racialised meanings that occur between macro-level and micro-level racial projects. This thesis aims to fill the gap left by this focus through examining racial projects that occupy the socio-political "middle ground" between macro- and micro-level projects: the "meso-level."The research examines the ways in which the state constructs mixed race in the United States and Britain. Each nation's census allowed for mixed race self identification in 2000 and 2001, respectively. The thesis examines the social, historical, and political processes that led to mixed race options at that particular time. It argues that the ways in which the census organisations report upon mixed race functions as a discursive practice that provides an official construction of mixed race through simultaneously reflecting and shaping racialised descriptions and narratives within each nation. The thesis examines the usefulness of "meso-level" projects by exploring the role of mixed race organisations in racial formation processes through the examination of six meso-level mechanisms of racialisation: social identity, social capital, collective action, idioculture, extended networks, and civil society (Fine 2012). Incorporating Michel Foucault's notion of "governmentality" (Gordon 1991), the thesis highlights the ways that mixed race organisations have interacted directly and indirectly with macro-level bodies during and after the addition of the mixed race census options as well as other routes of interaction specific to each national context. The thesis argues that the racialisation that occurs at the macro-level holds a "default" role with which mixed race organisations then engage. This highlights the relative roles of power the institutions have in each national context and the ways they are managed through relations fostered through governmentality. The thesis also examines the discourses used by mixed race organisations in the US and Britain as meso-level racial projects and poses the argument that the varied usage of multiple racialised paradigms leads to an increased relative fluidity in the constructions of mixed race than their respective macro-level projects. The systematic cross-national comparison of the ways mixed race is constructed in the US and Britain highlights the ways in which both macro-level and meso-level organisations articulate and promote racialised ideology through their relative levels of power in society. By analysing and comparing these racial projects and their interactions, the paradigms and discourses used reveal the particularities and overlaps by these organisations as they contest, negotiate, and accept formations of mixed race.

Thesis (Ph. D.)--Miami University, Dept. of Educational Leadership, 2004. / Title from second page of PDF document. Includes bibliographical references (p. 168-208).