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Differences In Quality Of Care By Insurance Plan: A Fee-For-Service Vs. Health Maintenance Organization Comparison, Pamela Driggers Silcox

Doctoral Dissertations

The history of health insurance in the United States has perpetuated and enabled a health care industry that has been rewarded for increased spending rather than cost control. With the original plan setting no spending limit on health care providers, fee-for service reimbursement provided greater incentive to spend than to contain costs. Attempts to control the soaring costs of health care services have given rise to managed care insurance plans that base reimbursement on health outcome data. Given that the birth of managed care includes stringent reimbursement guidelines and ensuing controversy over services provided or not provided, this study sought …

A Qualitative Investigation Of Polish Consumers’ Retail Experiences During The Transitional Period: 1989-2001, Heesun Seo

Doctoral Dissertations

The general objective of this dissertation is to investigate the most current phenomenon in the Polish retail environment and the recent Polish consumers’ retail experience. Specifically, by examining information search behavior, shopping behavior, and post-purchase behavior, themes emerged in terms of how the changes in the retail environment influenced the patronage and consumption behavior of Polish consumers. An exploratory research approach is used to conduct this research due to the lack of existing knowledge on Polish consumers and the ever-changing nature of the market environment in Poland. Moreover, qualitative research method with naturalistic inquiry was used to present the Polish …

Habitat Use, Distribution And Conservation Status Of The Mikado Pheasant (Syrmaticus Mikado) In Taiwan, Cara Lin Bridgman

Doctoral Dissertations

To evaluate the conservation status of Taiwan’s mikado pheasant, Syrmaticus mikado (Phasianidae), I test the similarity of preferred habitat to primary and secondary forest, develop models of habitat availability within Taiwan, and examine population trends within two locations inside Yushan National Park. The characteristics of locations with pheasant activity were most similar to secondary forest: high shrub stem counts and low canopy and leaf litter coverage. None of these variables were applicable to geographic informationsystems analysis. To the known extent of range and area of occupancy, I compared a model based on the habitats described in field guides. This model …

Using Remote Sensing And Geographic Information Systems To Define Conservation Priorities, Clinton N. Jenkins

Doctoral Dissertations

This dissertation discusses several techniques of combining ecology and technology, specifically satellite images and geographic information systems, to define conservation priorities and answer conservation questions. They include single species approaches (chapters 2 and 3), global approaches (chapter 4), and regional approaches (chapters 5 and 6).

Chapters 2 and 3 concern the Cape Sable Seaside Sparrow (Ammodramus mirabilis maritimus). This sparrow, and its habitat, is legally protected under the United States Endangered Species Act. Chapter 2 quantitatively demonstrates that poor water management is threatening the habitat of this sparrow and by consequence its survival. Chapter 3 describes formal testing …

Colonization History And Alternative Community States In Experimental Microcosms, Craig Richard Zimmermann

Doctoral Dissertations

Using s suite of disparate experimental systems, three tests of the effect of variation in community history on community states were performed. The first test explored the effect of species invasion order on the structure and invasibility in soil microbial communities. Microcosm communities were assembled by augmenting an existing soil community with sequential introductions of three bacterial strains under three alternative sequences. Assembled communities were then probed with a genetically engineered bioremediative bacterium to test the relative vulnerability of these communities to this strain. Results indicated that variation in invasion order resulted in the production of alternative community states with …

How Mothers Make Decisions For Feeding Young Children: A Grounded Theory Approach, Dana Rae Cox

Doctoral Dissertations

In this study a theory of how mothers make decisions about feeding their young children aged 3 to 5 years was developed using the grounded theory technique. In-depth interviews were conducted with 50 married mothers of children aged 3 to 5 to determine their mealtime practices and feelings about mealtimes. Interviews were audio taped and transcribed verbatim. Transcribed interviews were analyzed using the grounded theory technique to build a theory from the data (interviews).

Analyses of mothers’ interviews indicated that mothers in this study formed expectations for 5 distinct stages of feeding decisions based on their experiences. The five stages …

Investigation Of Biochemical Mechanisms Associated With Insulin Resistance In The Non-Insulin-Dependent Diabetes Mellitus, To-Yu Huang

Doctoral Dissertations

Non-insulin dependent diabetes mellitus (NIDDM) is a heterogeneous disease arising from metabolic defects in insulin secretion and insulin action. The inability of insulin to trigger full metabolic responses results in impaired glucose transport, which elicits compensatory hyperinsulinemia with increased lipogenesis. In order to identify the molecular defects responsible for insulin resistance, we have investigated three different model systems: the ability of sulfonylurea receptor (SUR) ligands to modify insulin regulated events in cultured rodent adipocytes; the ability of agouti and/or agouti related polypeptide (AGRP) to modify insulin regulated events; and the regulation of the activity and amount of the HNF-1a transcription …

Monographic Studies In The Genus Polyporus (Basidiomycotina), Dirk Krueger

Doctoral Dissertations

The aim of this dissertation research was an examination of the homobasidiomycete genus Polyporus as currently circumscribed. Emphasis was on addressing the genus by a variety of tools appropriate to modern monographic studies, without producing another worldwide monograph. In addition to morphological examination, which traditionally was the basis of all fungal systematics, mating experiments with monokaryotic cultures, and contemporary phylogenetic tools were used.

For P. alveolaris, P. arcularius, P. badius, P. brumalis, P. ciliatus, P. dictyopus, P. guianensis, P. melanopus, P. tubaeformis, P. tuberaster, P. tricholoma, P. umbellatus, and …

Molecular, Genetic, And Functional Analysis Of Ptr3p, A Novel Protein Involved In Amino Acid And Dipeptide Regulation Of Di/Tri-Peptide Transport System In Saccharomyces Cerevisiae, Vanny Narita

Doctoral Dissertations

The yeast Saccharomyces cerevisiae utilizes nutrient sensor activity at the plasma membrane to regulate growth. Amino acids are sensed by the membrane protein Ssy1p, and a signal is transduced to the novel intracellular regulatory protein Ptr3p. This leads to an upregulation of the expression of amino acid permease genes and PTR2, the gene encoding the di/tri-peptide transporter Ptr2p. Using a reporter gene assay, this study found that various amino acids induced PTR2 expression to different levels. Peptide and amino acid induction required Ptr3p, while Ssy1p was required for amino acid induction, but not peptide induction. Ptr3p-mediated, amino acid/dipeptide-induced expression …

Light And Water Induced Morphological Changes In Arabidopsis Thaliana (L.) Heynh. Plasticity And Selection, Anna Maria Kolodynska

Doctoral Dissertations

Phenotypic plasticity, the effect of plastic traits on fitness, and the stability of genetic variance-covariance matrices were investigated in an artificial population of Arabidopsis thaliana in response to environmental stress. These questions were also investigated in a selection experiment, where plants were subjected to selection on reproductive fitness (fruit production) under flooded and non-flooded water regimes.

Forty-seven accessions of early flowering A. thaliana were grown in laboratory conditions and were subjected to environmental stress such as low and medium light intensity, flooded and non-flooded water regimes, and a factorial arrangement of these light and water stresses. In addition, soft selection …

Interactions Among Introduced Ungulates, Plants, And Pollinators: A Field Study In The Temperate Forest Of The Southern Andes, Diego P. Vazquez

Doctoral Dissertations

Introduced mammalian herbivores can significantly affect ecosystems. I studied the effects of introduced ungulates on plant-pollinator interactions in the temperate forest of the southern Andes. Introduced mammalian herbivores, including ungulates, are a major conservation problem in this biome. I conducted field studies in eight forested sites where Nothofagus dombeyii was the dominant canopy tree. I described the interactions between fifteen common, insect-pollinated understory plants. I used these data to address two main questions. The first one is whether the susceptibility of plants and pollinators to disturbance by introduced ungulates is related to their degree of interaction specialization and interaction asymmetry. …