This study seeks to explore the relationship between intercultural communication experiences and college persistence in first-generation college students from the Central Appalachian region. Because Appalachia has a rich and unique culture, which is often misunderstood, the literature review seeks to establish a basis for studying this relationship as a way to understand the multi-dimensional nature of low-educational attainment in the Appalachian region, particularly Eastern Kentucky, Tennessee, Virginia, and West Virginia. Using a survey-based quantitative method this study examines Appalachian first generation students attending college as an intercultural communication process through the frame of acculturation theory. Specifically, the study seeks information about the students’ previous intercultural communication experiences, cultural identity, intercultural sensitivity, and college persistence. This study attempts to predict first generation, Appalachian students’ college persistence with their previous intercultural communication experiences, cultural identity, and intercultural sensitivity.

In this thesis, I try to proceed one step further towards an understanding of the biogeographic processes forming the distribution patterns of organisms that we see today. Babblers and warblers are diverse groups of passerines that are phylogenetically intermixed with other groups in the superfamily Sylvioidea. First, the gross phylogeny of the babblers and associated groups was estimated. Five major lineages of a well-supported monophyletic babbler radiation were recovered, and we proposed a new classification at family and subfamily level. Further, the genus Pnoepyga was excluded from Timaliidae, and we proposed the new family Pnoepygidae fam. nov. Second, the systematic position was investigated for the Albertine Rift taxon Hemitesia neumanni, which was found to be nested within the almost entirely Asian family Cettidae, and possible biogeographical scenarios were discussed. We concluded that the most plausible explanation involved late Miocene vicariance in combination with local extinctions. Third, the historical biogeography of a Leiothrichinae subclade, the Turdoides babblers and allies, was inferred. We concluded that the Middle East region probably played an important role in the early history of this clade, followed by local extinctions in this region. Fourth, a Bayesian method to reconstruct the historical biogeography under an event-based model was proposed, where the total biogeographic histories are sampled from its posterior probability distribution using Markov chains. In conclusion, I believe that, especially with more sophisticated methods available, we will see an increasing number of studies inferring biogeographic histories that lead to distribution patterns built up by a combination of dispersals and vicariance, but where these distributions have been extensively reshaped, or litterally demolished, by local extinctions. Therefore, my answer to the frequently asked question dispersal or vicariance? is both, but not the least: extinctions. / At the time of the doctoral defence the following papers were unpublished and had a status as follows; Papers 3 and 4: Manuscripts

Surface mining of the Athabasca Oil Sands of Canada is occurring at an unparalleled rate resulting in large scale disturbances over vast areas. Soil water availability for plants is one of the key issues faced when reclaiming the landscape. A factor which limits the soil water availability is soil water repellency (SWR). Soil water repellency is found on both natural and disturbed sites in this region and can cause reduced infiltration, reduced soil water storage, enhanced runoff, increased preferential flow, and reduced ecosystem productivity. Effective characterization of SWR, determination of the causes of SWR and understanding how it affects soil pores and water flow are important for environmental management. The main objective of this study is to examine the effect of SWR and fungal hydrophobicity on soil water dynamics in Athabasca Oil Sands. This was accomplished by determining the relationship between the measurement of severity and persistence of SWR and the critical water content (CWC) where SWR is greatest between different soils in the region. Examining how the water conducting porosity and soil pores are affected by SWR. Developing methods to quantify fungal strains that cause SWR and testing of these fungal strains for their ability to alter the SWR and infiltration into soil. Results show that a high severity (Contact angle) of repellency does not necessarily denote long persistence (Water Drop Penetration Time) or high CWC in soils from the region. A high severity of SWR in larger diameter pores decreased the water conducting porosity due to the larger pore contribution to the total liquid flux. The modified microscopy approach and the alcohol percentage test (APT) resulted in improved characterization of fungal hydrophobicity. Fungal strains were classified as hydrophilic, hydrophobic and chrono-amphililic based on their surface properties from these measurements. The surface property of selected fungi strains can alter the SWR in both a repellent and wettable soil and can also change the water infiltration rate. This research highlights the importance of characterization of SWR, the effects on water flow, and how fungal hydrophobicity can alter the SWR and infiltration. This will aid in improving our understanding of SWR and improve remediation efforts on water repellent soils in the Athabasca Oil Sands region.

Researchers report the need for attrition and persistence studies of adult college students. While adults are enrolling in colleges in record numbers, high percentages are also dropping out. The majority of studies have been completed on 18 to 21 year-old traditional students who have different views, perspectives, and needs than adult students. The purpose of this study was to identify characteristics that have contributed to the persistence of adult commuter students who have earned 60 or more semester hours of college credit.The study was conducted at a midsize midwestern commuter college. The model of Bean and Metzner (1985) was used for the study. Evidence was gathered by in-depth, structured interviews of 20 college students who had completed 60 or more hours of college credit. Using a qualitative analysis, responses were transcribed and inserted in a prestructured case outline. Contact summary sheets, clusters, a frequency network, and two matrices were constructed to weigh the evidence, the characteristics that contributed to persistence, and to note the themes and patterns.The research indicated students varied by ethnicity, social class, and gender. Conclusions were that self-reliance was a characteristic of persistent students who assumed control for selecting courses, attending classes, and studying. Social support from outside or inside the university and a time commitment to college were important. Sufficient study skills, the discipline to study alone, and time management skills were also hallmarks of the successful students. The student's perception that the student was succeeding the first year of college appeared to be important. Beginning college at risk appeared to make only a slight difference in students at 60 or more hours of college.Implications were that administrators should educate students as to what characteristics contribute to success, and, when possible, provide characteristics of success so adult students persist to degree completion. Providing characteristics of success may promote persistence more than eliminating characteristics of dropouts. Recommendations were made for further gender, ethnic, socioeconomic, and developmental studies. / Department of Educational Leadership

Nei paesi democratici, le elezioni rappresentano il principale meccanismo per garantire che, una volta eletto, un politico agisca effettivamente nell'interesse della collettività. Nel primo capitolo, presento una rassegna della letteratura sull'electoral accountability. Nel secondo capitolo, mostro come la presenza delle elezioni possa essere la causa della riluttanza dei politici ad investire in beni pubblici di lungo periodo (political short-termism), e come tale comportamento possa essere ottimale per la collettività. Nel terzo capitolo, mostro come l'interesse per la rielezione possa indurre un politico a continuare una politica che aveva intrapreso in passato anche quando sarebbe ottimale per la collettività cambiare politica , e a non continuare una politica introdotta in passato da un politico rivale anche quando sarebbe ottimale per la collettività non cambiare politica. Questi risultati possono aiutare a spiegare perchè i politici in carica hanno un "vantaggio elettorale" rispetto ai nuovi politici. / In the democratic countries, elections are the primary mechanism for ensuring that, once in office, a politician actually acts in the collectivity's interest. In the first chapter, I present a survey of the literature on electoral accountability. In the second chapter, I show that the presence of the elections may be the cause of the politicians' reluctance to invest in long-term public goods (political short-termism), and such behavior may be optimal for the collectivity. In the third chapter, I show that reelection concern may induce a politician to continue a policy he introduced in the past even when a policy change would be optimal for the collectivity, and not to continue a policy introduced in the past by a rival politician even when a policy change would not be optimal for the collectivity. These results may help to explain why the incumbent politicians have an "electoral advantage" over new politicians.

We study diffusion-reaction-advection models describing population dynamics of aquatic organisms subject to a constant drift, with reflecting upstream and outflow downstream boundary conditions. We consider three different models: single logistically growing species, two and three competing species. In the case of a single population, we determine conditions for existence, uniqueness and stability of non-trivial steady-state solutions. We analyze the dependence of such solutions on advection speed, growth rate and length of the habitat. Such analysis offers a possible explanation of the "drift paradox" in our context. We also introduce a spatially implicit ODE (nonspatial approximation) model which captures the essential behavior of the original PDE model. In the case of two competing species, we use a diffusion-advection version of the Lotka-Volterra competition model. Combining numerical and analytical techniques, in both the spatial and nonspatial approximation settings, we describe the effect of advection on competitive outcomes. Finally, in the case of three species, we use the nonspatial approximation approach to analyze and classify the possible scenarios as we change the flow speed in the habitat.

This study deals with the contribution of the genetic variant lactase persistence among Neolithic people from the Baltic Island Öland. Skeletal remains from twelve individuals went through DNA sequencing in order to find the mutation that allows adult individuals to digest milk sugar. The twelve individuals were chosen from two different Neolithic sites, where the archaeological and isotopic data suggest that the individuals from Köpingsvik were hunters and gatherers and the individuals from Resmo were early farmers. The individuals with the genetic variant lactase persistence can be described with selection and genetic flow.  Only five individuals produced results and the mutation was found in two of the subjects. All the individuals who were successfully sequenced came from Resmo, whereasno individuals from Köpingsvik yielded any results.

Chlamydia, caused by the bacterium Chlamydia trachomatis, is one of the most important sexually-transmitted infections globally. In addition to accounting for millions of cases every year, the disease causes numerous irreversible complications such as chronic pelvic pain, infertility in females and pelvic inflammatory disease. This thesis presents a number of mathematical models, of the form of deterministic systems of non-linear differential equations, for gaining qualitative insight into the transmission dynamics and control of Chlamydia within an infected host (in vivo) and in a population. The models designed address numerous important issues relating to the transmission dynamics of Chlamydia trachomatis, such as the roles of immune response, sex structure, time delay (in modelling the latency period) and risk structure (i.e., risk of acquiring or transmitting infection). The in-host model is shown to have a globally-asymptotically stable Chlamydia-free equilibrium whenever a certain biological threshold is less than unity. It has a unique Chlamydia-present equilibrium when the threshold exceeds unity. Unlike the in-host model, the two-group (males and females) population-level model undergoes a backward bifurcation, where a stable disease-free equilibrium co-exists with one or more stable endemic equilibria when the associated reproduction number is less than unity. This phenomenon, which is shown to be caused by the re-infection of recovered individuals, makes the effort to eliminate the disease from the population more difficult. Extending the two-group model to incorporate risk structure shows that the backward bifurcation phenomenon persists even when recovered individuals do not acquire re-infection. In other words, it is shown that stratifying the sexually-active population in terms of risk of acquiring or transmitting infection guarantees the presence of backward bifurcation in the transmission dynamics of Chlamydia in a population. Finally, it is shown (via numerical simulations) that a future Chlamydia vaccine that boosts cell-mediated immune response will be more effective in curtailing Chlamydia burden in vivo than a vaccine that enhances humoral immune response. The population-level impact of various targeted treatment strategies, in controlling the spread of Chlamydia in a population, are compared. In particular, it is shown that the use of treatment could have positive or negative population-level impact (depending on the sign of a certain epidemiological threshold).

To understand the temporal dynamics of a forest, long-term direct observations are required. My study examined the long-term persistence of trembling aspen (Populus tremuloides Michx) and white spruce (Picea glauca (Moench) Voss) in the boreal mixed-wood forests of Riding Mountain National Park. A set of 266, disturbance-free, permanent sample plots were established in 1947 (stand age = 120 years) and followed through time for 55 years. My results indicate that although the density and basal areas of aspen do decline over the 55-year period, a successful regeneration and establishment occurs around 140 years. The long-term persistence of aspen is a result of clonal reproduction following the canopy breakup beginning around 130 years or earlier. This implies that the long-term persistence of both aspen and spruce occur and the expected succession to softwood dominance does not occur.

In this thesis I detail an easy to use system for dynamic data storage aimed at use in educational games and game systems. Evaluation of current approaches in use by educators and students suggest a large degree of ad hoc systems in place for data persistence. I evaluate my system against existing techniques including a flat file, XML, and SQL systems. I provide a dynamic, easy to use solution to data persistence in the environment of educational game development.