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Juvenile-onset systemic lupus erythematosus (JSLE) is a complex autoimmune disorder characterised by chronic inflammation, multiple organ damage and increased risk of cardiovascular disease (CVD). Disease onset in JSLE is more common during puberty and the female to male ratio is 4.5:1, suggesting a hormonal importance in disease pathogenesis. Work by the Jury lab in adult-onset SLE links immune cell dysregulation with defects in plasma membrane lipids rafts; signalling platforms that facilitate immune cell activation and effector function. However, in patients with JSLE, the immune system is still developing and very little is known about disease pathogenesis, whether it is the same as adult disease and whether the same treatments available to the adults are relevant for this younger group of patients. My hypothesis is that altered lipid metabolism leads to changes in immune cell function; differences in lipid metabolism exist between males and females and defects in these pathways contribute to JSLE pathogenesis. My aims were to 1) investigate sex differences in immune and metabolic phenotype in healthy individuals and JSLE patients, 2) assess the relationship between immune cells and serum lipids and 3) identify predictive biomarkers for CVD risk in JSLE. Using in depth immunophenotyping by flow cytometry and metabolomic analysis, this study has identified fundamental differences between healthy adolescent males and females. Males had increased regulatory T-cell (Treg) frequencies, altered lipid raft profiles and functional differences including an increased IL-4 production and suppressive capacity compared to females. These Treg phenotypic differences were associated with the very low density lipoprotein (VLDL) signature connected with males. In a chronic inflammatory setting (JSLE), these differences were lost between males and females. I also found that JSLE patients could be stratified according to their serum lipoprotein profile allowing potential identification of patients with increased CVD risk. This work provides evidence that a combination of pubertal development, immune cell defects and dyslipidemia may contribute to JSLE pathogenesis. Patient stratification has identified a unique group of patients that could benefit from lipid modification therapy, reducing both CVD risk and immune cell activity.

This thesis studies the failure mechanism of plain concrete. The purpose is to explain the elastic and strength properties of concrete in terms of its internal structure. The study is presented in five parts. 1) The analysis of Part I studies the existing failure theories both qualitatively and statistically in terms of data from 516 tests. From this it is suggested that the volumetric and deviatoric stresses, and a limiting tensile strain are important to the failure of concrete. Furthermore it is shown that it is necessary to study the heterogeneous nature of concrete and the definition of failure. 2) Part II contains an analytical study of the heterogeneous nature of concrete, considering first one inclusion, and then the interactions of numerous inclusions. For the latter analysis, an idealized packing (model) is assumed. With this it is possible to simulate many aspects of the behaviour of concrete in uniaxial compression. Both these analyses offered an explanation for the modes of failure in concrete and emphasized the importance of a limiting tensile strain. 3) Part III describes a coordinated series of tests to study the influence of the internal structure of concrete and microcracking on the behaviour of concrete. Acoustic, pulse velocity, and a specially developed X-ray technique were used. This series provided information not only about the formation, location, and size of microcracks and the effect of coarse aggregate, but also the capabilities of the testing techniques. Thus it is possible to describe the behaviour of concrete in uniaxial compression in terms of its structure and to propose a definition for the failure of concrete. 4) Part IV extends the discussion of the previous sections to biaxial compression by developing and proving a biaxial compression testing machine and then conducting a series of tests on 10 x 10 x 4 inch concrete and mortar slabs. The effect of the lateral load is shown on the strength, Young's modulus, and Poisson's ratio. 5) On this basis, the discussion in Part V proposes a rational explanation for the behaviour of concrete in biaxial compression in terms of the interactions of the structural elements of the concrete. It is sugest-d that the volumetric stress and a limiting tensile strain in the paste are critical to the failure of concrete.

This study utilized a mediation/moderation mixed model to examine the direct and indirect links between marital conflict and children's asocial and excluded behaviors as rated by teachers. The ecological validity of this study was enhanced by using independent raters of children's behavior and direct observations of parenting behavior. The participants (n = 72) in this study were a combination of families with substantiated cases of physical abuse that were referred by a state human services agency and families recruited from the community. Participating children had a mean age of 7.3 years and ranged between 4 and 9 years old. To determine direct effects, marital conflict was assessed using a modified version of the Conflict Tactics Scales. Children's social behaviors were measured by two subscales on the Social Behavior Scale. To calculate indirect effects mediated through parenting behavior, parents and children participated in three 10-minute vignettes that were videotaped and coded. Overall, results supported a direct effects model in which marital conflict predicted 5% of the variance in children's asocial behavior. Asocial behaviors in the classroom were also significantly associated with peer rejection and low engagement on the playground. Although moderation of the relation between marital conflict and the three parenting behavior domains by parental anxiety, depression, and stress was not supported, substantial support was found for the negative impact of parent psychopathology and stress had on parenting behavior. Prevention/intervention efforts for children and parents using a family systems perspective were emphasized.,[superscript Superscript],[subscript Subscript],done.

This research documents dissimilar outcomes found in two petrochemical plants responding to a common corporate mandate to institute more participative practices. Participative practices in teams, the focus of this report, are analyzed to learn ways in which they reflect a value upon either individualism or collectivism. The analysis chapters explain how human resource systems, plant manager's style, and national culture can influence participation in teams in ways that foster a collective agenda and dampen the self-interest of individual team members or vice versa. This work is distinctive in combining the anthropological methods of emic and etic description and analysis with a functional examination of bureaucratic dysfunctions. Major research findings include the following: that favorable conditions for participation obtain when systems align with organizational structure; that members who exhibit good group skills and can serve as their own process consultants are central to developing self-managing teams; that participation is a "hard sell" to most US business executives because of its countercultural values and their successes without it; that national cultures provide uniquely different contexts which exert muted but unmistakable influence on partici pation; and, finally, that attending to members' personal meanings of the concept "team", created from their first hand experiences, reveals variants of participation. The findings imply that practitioners launching participative changes can expect increased congruence between efforts and success when they actively discern potential participants' personal meanings about teamwork. These data will give them an edge when orchestrating action via the web of structure, systems, actors and culture, all of which alternately pose restraints upon and create unique opportunities for participation. For scholars, studying participation is important because its use is much more likely in the immediate and protracted future. Competitive pressures ensure this despite cynicism about its effectiveness among executives and recipients of past doses. Furthermore, participation goads academicians and practitioners alike to grapple with a conundrum: how to bring the harmonious social relations and mutual dependence of collective thought to economic enterprise which typically treats human beings as instruments and generally rewards individual achievement and self-reliance rather than collaboration with others

The purpose of this study was to compare practices in the secondary schools in which graduates of North Texas State Teachers College are employed with standards and techiques concerning vocational guidance which have been set up by writers in the field.

A detailed investigation of the geology of the southern one-half of the Millerstown, Pennsylvania 15 Minute Topographic Quandrangle was conducted during 1956-1957. This report of the work contains a description of the Silurian, Devonian, and Mississippian formations which crop out in the area. The complex folding and faulting of the sediments is outlined in a section on structural geology. A number of anticlines and synclines, not previously mapped, are described. A geologic map and two structural cross sections with a scale of 1:24000 are included to illustrate the features described. This is the first geologic map of the area on a topographic base. A short discussion of drainage patterns and alignment of gaps is also included. Past utilization of the natural resources of the area and possible future development is discussed in a section on economic geology.

U.M.