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Thesis (Ph. D.)--University of Missouri-Columbia, 2002. / Typescript. Vita. Includes bibliographical references (leaves 154-170). Also available on the Internet.

Thesis (Ph. D.)--University of Missouri-Columbia, 2002. / Typescript. Vita. Includes bibliographical references (leaves 154-170). Also available on the Internet.

Scleractinian corals represent the foundation species of one of the most diverse and productive ecosystem on earth, coral reefs. Corals not only constitute the trophic basis of these ecosystems, but also provide essential habitats and shelter for a wide variety of marine species, many of which are commercially relevant. They also provide other important ecosystem services such as food provision, shoreline protection and opportunities for ecotourism. Despite the ecological importance of corals, very little is known about how their soft-bodied ancestor evolved the ability to form a calcified skeleton and became the ecosystem builders they are today. Corallimorpharia are closely related to reef-building corals but lack the ability to form calcified skeletons. Here we assembled and annotated two draft genomes of the corallimorpharians, Amplexidiscus fenestrafer and Discosoma sp., and further provided an online interface to facilitate the use of these resources. The two genomes can not only inform on the current evolutionary gap in genomic resources for the subclass of Hexacorallia but also provide important resources for comparative genomic studies aiming at understanding the evolution of coral specific traits. Our broad phylogenomic approach using whole genome data, including phylogenetic analyses of nuclear encoding genes as well as genome-wide presence/absence information and synteny conservation from six hexacorallian species, provides robust evidence that corallimorpharians are a monophyletic sister group of scleractinians, therefore rejecting the “naked coral” hypothesis. Being the closest non-calcifying relative of scleractinian corals, corallimorpharians appear to be the best candidates to understand the evolutionary origin of coral calcification. Molecular divergence analysis of scleractinian coral and Corallimorpharia genes suggests that the soft-bodied ancestor of corals evolved the ability to calcify within approximately 80 million years after the divergence of these two orders. To uncover the molecular basis of coral skeletal formation and growth, we integrate genomic and transcriptomic data as well as skeletal proteomic data, and show that gene and domain duplications have been the main evolutionary mechanisms underlying the evolution of calcification in scleractinian corals.

This paper discusses the issue of residential segregation in Halmstad, a municipality in western Sweden. The inhabitants themselves say that it is one of the most segregated municipalities in the country and the growing segregation is affecting the community in various ways, particularly in the housing market, where increased segregation has resulted in decreased quality and safety in these areas, as well as decreased cohesion between different areas in the municipality. The paper aims to explain the forms of residential segregation in society using four theories: The planning hypothesis, market hypothesis, status hypothesis, and contact hypothesis. The research method used is the case study method, which is suitable for analyzing a “case” of broader phenomenon. One method that has been considered appropriate within the case study literature for testing theories, as this study does, is pattern matching, also known as congruence matching. This method tests the extent of which the empirical pattern matches the hypothetical pattern that the theory assumes. If there is lack of congruence between the empirical pattern and the theoretically assumed pattern, the result speak against the theoretical hypothesis. If the congruence is found, the theoretical hypothesis is supported. The planning hypothesis could confirm that the municipality ́s planning has had segregated effects and the efforts have not been sufficient to counteract residential segregation. The market hypothesis could not be confirmed because the housing market is not governed by market rents. The paper also found patterns that strengthened the status hypothesis. Partly by finding material that shows that Halmstad is a polarized municipality with areas that have lower status than others. Lastly, the contact hypothesis could partly be confirmed by looking at increased family immigration.

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Student Number : 9905625D - MSc dissertation - School of Animal, Plant and Environment Science - Faculty of Science / Stereotypic behaviours are repetitive invariant behaviours that serve no obvious purpose and are common in both domestic and non-domestic captive animals. Stereotypies are regarded as indicators of poor welfare although the growing body of work pertaining to these behaviours has challenged many previously held notions of stereotypy. The most widely accepted, although frequently contested, hypothesis used to explain stereotypies is the coping hypothesis, which states that animals perform stereotypies to cope with the stress of adverse environments. The aim of my study was to investigate the fitness effects of stereotypy, and whether or not environmental enrichment protocols were effective in reducing or eliminating stereotypy in the adult striped mouse Rhabdomys pumilio. Both of these experiments were designed to evaluate the coping hypothesis. I intentionally used wild caught and F1 individuals to eliminate any potential captive selection bias that may exist in extant captive populations that could affect interpretation of fitness. For the first aim, 40 breeding pairs were assigned to one of four treatments: 1) stereotypic female and stereotypic male (S-S); 2) stereotypic female and non-stereotypic male (S-NS); 3) non-stereotypic female and stereotypic male (NS-S); and 4) non-stereotypic female and non-stereotypic male (NS-NS). Compared to non-stereotypic females, stereotypic striped mice females had better reproductive output, including larger litter size, higher growth rate, higher litter survival, shorter interlitter interval and shorter time to first litter. Reproductive success was higher in S-S and S-NS pairs, indicating that genetic and maternal effects jointly determined fitness in striped mice. Unlike other published research, maternal mass was not a predictor of fitness. For the second aim, I housed 20 non-stereotypic and 20 stereotypic striped mice (equal sex ratio) in barren cages for 60 days, and transferred them to enriched cages, and repeated this experiment with striped mice housed initially in enriched cages and transferred to barren cages. While there was a measurable reduction in stereotypy in individuals transferred from barren to enriched environment cages, no increase in stereotypy was noted in striped mice transferred from enriched to barren cages. These findings appear to concur with the coping hypothesis, that stereotypies become perseverative (e.g. bad habits) and difficult to disrupt. Non-stereotypic striped mice were not influenced by the swap. I conclude that the expression of stereotypy is a potential sign of positive welfare and that it may be worthwhile to specifically elicit stereotypic behaviours in order to improve the welfare, and in certain cases, breeding success, of captive animals. Moreover, I maintain that where necessary, effort should be applied to combating stereotypies before they arise, rather than attempting to eliminate them once they have actually developed.

Background: Phase Three of the International Study of Asthma and Allergies in Childhood (ISAAC) measured the global prevalence of symptoms of asthma in children. We undertook comprehensive analyses addressing risk factors for asthma symptoms in combination, at both the individual and the school level, to explore the potential role of reverse causation due to selective avoidance or confounding by indication. Objective: To explore the role of reverse causation in risk factors of asthma symptoms. Methods: We compared two sets of multilevel logistic regression analyses, using (a) individual level exposure data and (b) school level average exposure (ie prevalence), in two different age groups. In individual level analyses, reverse causation is a possible concern if individual level exposure statuses were changed as a result of asthma symptoms or diagnosis. School level analyses may suffer from ecologic confounding, but reverse causation is less of a concern because individual changes in exposure status as a result of asthma symptoms would only have a small effect on overall school exposure levels. Results: There were 131 924 children aged 6-7 years (2428 schools, 25 countries) with complete exposure, outcome and confounder data. The strongest associations in individual level analyses (fully adjusted) were for current paracetamol use (odds ratio = 2.06; 95% confidence interval 1.97-2.16), early life antibiotic use (1.65; 1.58-1.73) and open fire cooking (1.44; 1.26-1.65). In school level analyses, these risk factors again showed increased risks. There were 238 586 adolescents aged 13-14 years (2072 schools, 42 countries) with complete exposure, outcome and confounder data. The strongest associations in individual level analyses (fully adjusted) were for current paracetamol use (1.80; 1.75-1.86), cooking on an open fire (1.32; 1.22-1.43) and maternal tobacco use (1.23; 1.18-1.27). In school level analyses, these risk factors again showed increased risks. Conclusions & clinical relevance: These analyses strengthen the potentially causal interpretation of previously reported individual level findings, by providing evidence against reverse causation. / Revisión por pares