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Modeling Of Aqueous Equilibrium: Three-Dimensional Trend Surfaces (Topos), Mohammad Mainul Hossain

Graduate Student Theses, Dissertations, & Professional Papers

This dissertation establishes a comprehensive approach to looking at aqueous equilibria phenomena over essentially all feasible compositions of two component solutions - acid-base titrations, metal-ligand complexation, oxidation-reduction couples and solubility of binary ionic compounds. Fundamental to this method is the definition of a composition grid above which numerous system properties can be plotted as three-dimensional trend surfaces to visualize important aspects of system behavior. These have been named "topos" because their appearance is similar to topographic maps. In each case Microsoft ExcelTM worksheets have been designed with embedded Visual BasicTM macros that provide an easy means for anyone to generate …

The Politics Of Melancholy In Alfonso Cuarón’S Y Tu Mamá También, Children Of Men And The Possibility Of Hope, Jessica Anderson

Graduate Student Theses, Dissertations, & Professional Papers

This thesis examines how three films directed by Alfonso Cuarón, Y Tu Mamá También, Children of Men, and The Possibility of Hope, represent the impact of globalization on society and the environment. These films are thematically related, and intended to be considered in connection with one another, as indicated by both interviews with Cuarón, and by critical commentary informing audience reception of these works. Each film uses melancholy as a plot device, and as an ambient presence to elucidate Cuarón’s underlying message that we must re-examine the problematic social, economic and environmental consequences of neo-liberal capitalist models of globalization. Melancholy …

Theophylline And Ambrisentan Combination: Effects On Human Performance, Ams And Physiological Responses To Altitude, Hilary Linda Palakovich

Graduate Student Theses, Dissertations, & Professional Papers

Recent research efforts have attempted to determine the effectiveness of the combination of a pharmacological cardiac stimulant (theophylline) and pulmonary vasodilator (ambrisentan) in attenuating performance losses and mountain sickness at altitude. This combination has been observed to improve hypoxic exercise performance in rats, but never tested in human subjects. In the current study, 30 male participants were tested in a paired fashion to assess whether this drug combination would improve exercise performance and/or decrease symptoms of AMS. The experimental group (EXP, n = 15) received a treatment of 400 mg theophylline and 5 mg ambrisentan, while the placebo group (PLA, …

Use Of A Forest Reconstruction Model To Assess Changes To Sierra Nevada Mixed-Conifer Forest Conditions During The Fire Suppression Era, Molly Augusta Frederica Barth

Graduate Student Theses, Dissertations, & Professional Papers

Fire suppression has resulted in dramatic changes to species composition and structural diversity in the Sierra Nevada mixed-conifer forests of California. Advancing the ecological understanding and management of these forests requires a better understanding of changes that occurred during the fire suppression era, but empirical historical datasets are rare and methodologies for developing new historical reference information are subject to many limitations. I sought to develop historical reference information for the Yosemite Forest Dynamics Plot (YFDP), a research plot located in an old-growth mixed-conifer stand in Yosemite National Park. I performed a dendrochronological fire history analysis to characterize the historical …

Stakeholder Perspectives Regarding The Ecosystem Services Produced By The Frank Church - River Of No Return Wilderness In Central Idaho, Benjamin Thomas Irey

Graduate Student Theses, Dissertations, & Professional Papers

Wilderness management is directed by policy and legislation that mandates protection of the values associated with wilderness character. However, there is ample evidence to suggest that wilderness benefits society in many ways, beyond the values associated with wilderness character. If that is the case, then failure to account for those values will lead to socially inefficient management decisions. The Frank Church - River of No Return Wilderness (FC-RONRW) in central Idaho was selected as a case study region in which to test the hypothesis that society derives a multitude of benefits from wilderness in addition to those associated with wilderness …

Using Terrestrial Lidar To Model Shrubs For Fire Behavior Simulation, Theodore Adams

Graduate Student Theses, Dissertations, & Professional Papers

The purpose of this study was to spatially represent shrub fuel matrices accurately and at fine resolution for use in physics-based fire behavior simulations. Terrestrial Light Detection and Ranging (T-LiDAR) was used to measure shrub fuel beds in laboratory settings before and after fire burned through them. The primary goals of this research were to produce highly descriptive data-sets that correctly identified the locations of biomass within 3-D space without destructive sampling, and to derive attributes for fuel elements within the shrubs. This research was completed in two phases. First, a series of experiments was conducted to test the capacity …

Accuracy Assessment In Multivariate Bayesian Forecasting Linear And Nonlinear Models, Clark Joachim Kogan

Graduate Student Theses, Dissertations, & Professional Papers

Reduced alertness and high levels of cognitive fatigue due to sleep loss bring forth substantial risks in today's 24/7 society. Biomathematical models can be used to help mitigate such risks by predicting quantitative levels of fatigue under sleep loss. These models help manage risk by providing information on the timing at which high levels of fatigue will occur; countermeasures can then be taken to reduce accident risk at such critical times.

Many quantitative models exist to predict cognitive performance based on homeostatic and circadian processes (Mallis et al., 2004). These models have typically been fitted to group average data. Due …

Elaboration And Diversification Of Rhinoceros Beetle Horns, Erin Louisa Mccullough

Graduate Student Theses, Dissertations, & Professional Papers

Sexual selection is a potent driver in the evolution of male morphology and has given rise to bright, flashy ornaments that attract females, and big, bulky weapons that aid in male-male combat. Although previous studies have focused extensively on how female choice can drive the evolution and diversification of male ornaments, surprisingly little work has been done on the evolution of male weapons. Thus, we simply cannot convincingly explain why sexually-selected weapons are so diverse.

Biological Invasions: Insights Into Ecology And Evolution, Jennifer Naomi Smith

Graduate Student Theses, Dissertations, & Professional Papers

Introductions of exotic species commonly restructure native communities, but the mechanisms driving native species responses are poorly understood. Invasion biology has focused its research on the negative impacts of invaders, yet invaders can also have positive interactions. A holistic understanding of how biological invasions can have a full range of potential responses from negative to neutral to positive. Understanding the mechanics that underlie native species responses to invasions can help elucidate those factors structuring the native communities we see today. I used a combination of experimental and observational studies in the field and laboratory to determine the effects of spotted …

Cueing Complex Thought, Shannon Houck

Graduate Student Theses, Dissertations, & Professional Papers

Does exposure to a complex description subsequently cue a person to be more complex? To test this question, participants read a paragraph about a specific topic. Paragraphs varied in their level of Integrative Complexity. Participants then wrote about either (1) their opinion about the topic that they read about, or (2) their opinion about a topic that is unrelated to the one that they read about. Participant responses were scored for Integrative Complexity. Contrary to expectations, reading complex paragraphs did not cue people to write more complexly, regardless of whether they were assigned to write about a topic related or …

Thermodynamic And Kinetic Properties Of Cytochromes C And C’ In The Denatured State: Propensity For Residual Structure, Travis Arthur Danielson

Graduate Student Theses, Dissertations, & Professional Papers

To expand our understanding of helical propensity and residual structure in the denatured state, two approaches have been taken. In the first project, we have engineered serine in place of alanine near the center of the third helix (positions 83 and 87) in cytochrome c’ (Cytc’) and have measured histidine-heme loop formation in 3 M gdnHCl. A series of thirteen variants that include the A83S/A87S substitutions have been engineered with single surface histidine substitutions to provide a range of His-heme loop sizes from 10 to 111 residues and to provide direct comparison to previous studies with pWT Cytc’ . We …

Novel G-Quadruplex Binders With Potential For A Dual Dna Cross-Linking Mechanism Of Action, Nathan S. Duncan

Graduate Student Theses, Dissertations, & Professional Papers

Genomic DNA is organized around the double-stranded of B-form DNA, which is both durable and flexible enough to store and pass on genetic information. Once freed from the associations of an extended complimentary sequence, single stranded DNA and RNA can adopt a vast array of stable secondary structure motifs, such as stem-loop, pseudo-knots, and tetra-loops, ideal for its involvement in biological settings other than as a store of genetic information. Originally, alkylating agents were used as "mustard gas" and related chemical weapons in World War I. Alkylating agents, in general, can react with one or two different 7-N-guanine residues and …

Novel Ribosome Biogenesis In The Lyme Disease Spirochete Borrelia Burgdorferi, Melissa Lynn Hargreaves

Graduate Student Theses, Dissertations, & Professional Papers

Here we demonstrate the first characterization of an RNase III enzyme from a spirochete and its role in processing rRNA transcripts from the unusual rRNA gene operons of Borrelia burgdorferi. In most bacteria, the three rRNA transcripts (16S, 23S, and 5S rRNAs) that form the ribosome are produced as a single transcript from an operon with minimal spacing between genes. In the B. burgdorferi genome, however, a single 16S rRNA gene is encoded more than 3 kb from the bicistronic 23S-5S rRNA operons. The 23S-5S operons are tandemly duplicated, yielding an uneven number of rRNA genes, a feature unique to …

Control By Vegetation Disturbance On Gully Rejuvenation Following Wildfire, Kevin Hyde

Graduate Student Theses, Dissertations, & Professional Papers

Gully rejuvenation (GR) following wildfire influences landform evolution and generates flooding and debris that alters aquatic habitat and threatens human activities. Fire severity, defined as the degree of vegetation loss by wildfire, is a hypothesized control on this erosion response. I investigated three related aspects of the relationship between fire severity and GR: The capacity of vegetation disturbance to explain the occurrence or non-occurrence of GR; the spatial structure of burn mosaics relative to post-fire erosion; and the relationship between fire severity and threshold conditions required for channel initiation. I surveyed 269 burned catchments and mapped 111 cases of GR …

The Effects Of Temperature On Fungal Symbionts In The Mountain Pine Beetle-Fungus Multi-Partite Symbiosis, Melissa Lea Moore

Graduate Student Theses, Dissertations, & Professional Papers

The mountain pine beetle is an economically and ecologically important insect in western North American forests capable of killing millions of trees during outbreaks. This beetle depends on two fungi, Grosmannia clavigera and Ophiostoma montium, to provide the nutrients required for the beetle to develop and reproduce. Competition between these two fungal associates is expected because they use similar resources. Strong competition should lead to the eventual destabilization of the three-way symbiosis and fixation for the most competitive fungus. However, strong direct competition has not been observed, indicating that some mechanism likely allows the two fungi to coexist in a …

Examining Skewed Sex Ratio In The Mountain Plover (Charadrius Montanus) Population, Margaret Mercedes Riordan

Graduate Student Theses, Dissertations, & Professional Papers

Skewed sex ratios can have negative implications for population growth or persistence if not congruous for a species system. A skewed tertiary sex ratio (2.3 males per female) has been detected in the breeding population of a grassland shorebird experiencing population declines, the mountain plover (Charadrius montanus). To evaluate the ontogeny of the observed male skew this study examined the early life stages, from laying to fledging, of mountain plover young during their breeding season from 2010 – 2012 in eastern Colorado. The life stages between laying and fledging that allows for differentiation between production and survival of males and …

Dual Enrollment As A Factor For Women Transitioning Into Stem Majors In Montana Two-Year Colleges, Penny Jane Jakes

Graduate Student Theses, Dissertations, & Professional Papers

The purpose of this non-experimental, descriptive, quantitative study was to describe the impact high school dual enrollment coursework has had on initial enrollment of women with STEM majors in Montana two-year colleges. The study was designed to find whether or not differences existed for access (initial enrollment), persistence (to third semester), and success (associate's degree, certificate, or transfer to a four-year institution within 150% of program length). The literature review highlighted the need for studies to address the issue of few women in science, technology, engineering, and mathematics (STEM) occupations. One goal of dual enrollment in Montana is to ease …

Causes And Consequences Of Dominance And Diversity In Grasslands, Sarah Pinto

Graduate Student Theses, Dissertations, & Professional Papers

Understanding how species coexist and differ in abundance is central to ecology. Theory predicts competitively superior species should dominate systems and suppress diversity, yet many natural communities characterized by dominants are species rich. Understanding how shifts in dominance among species, and the inherent diversity of communities affect ecosystem function is a second central theme in ecology. For example, decreasing the number of species in local communities can reduce the ability of the community to respond to disturbance. These ideas have captured ecologists' attention because anthropogenic pressures are causing many systems to lose species. In my dissertation I focused on processes …

A Spatially-Explicit Decision Support System For Invasive Weed Species Management, Pablo Aracena

Graduate Student Theses, Dissertations, & Professional Papers

Invasive weed species are a recognized problem worldwide causing economic and environmental problems. Management of weeds is complex and challenging because of multiple decisions that need to be made when allocating limited resources to control current infestation areas including which weeds to treat, where to treat, how to treat, and when to treat. Models have been developed to simulate weed spread, however they lack the ability to simulate the short term effects of weed treatments and analyze trade-offs among control allocation options. This trade-off analysis is critical in developing cost-efficient treatment decisions especially when available budget for treatments is limited. …

Variations In Wildfire Ash Properties And Implications For Post-Fire Hydrological Response Within Western North American Ecosystems, Victoria Balfour

Graduate Student Theses, Dissertations, & Professional Papers

Within the Rocky Mountain region of the Western U.S.A the average number of wildfires over 40 hectares have quadrupled and the frequency of large wildfires (> 4,000 hectares) have increased seven times since the 1970’s. The effect of this increase on resource management and ecosystem function is of increased interest to agencies and land managers within the region. The research presented in this dissertation aimed to contribute to the growing knowledge of post-fire hydrology, specifically with regards to the role of wildfire ash within recently burned ecosystems. Ash should not be considered a generic term, as it is an important …

An Attributional Analysis Of Observers Helping The Bully In Bullying Episodes, Christopher James Bushard

Graduate Student Theses, Dissertations, & Professional Papers

Student attitudes regarding bullying are mixed. Although most students appear to condemn the behavior (Boulton & Underwood, 1992), a sizable minority group displays beliefs and attitudes supportive of bullying (Rigby & Slee, 1991; Rigby & Slee, 1993). Previous research has also found that students involved in bullying situations can be categorized into different roles based on their behaviors during bullying episodes (Samivalli, Huttunen, & Lagerspetz, 1997). An established method to measure and predict attitudes and thoughts about a person’s actions in a situation is to use an attribution framework. Weiner (1995) proposes an attribution model in which the observer’s thoughts …

The Relationship Between Montana Science Teachers Self-Efficacy And The Integration Of Web 2.0 Elements In The Classroom In Schools With A Student Population Over 900, Robert Dobell

Graduate Student Theses, Dissertations, & Professional Papers

Web 2.0 tools are part of the 21st century school, and are essential elements to teachers in the classroom as our students today are part of the digital generation (Prensky, 2001). Web 2.0 tools offer the instructor the ability to design the learning environment to focus on collaboration and a facilitation of content knowledge (Solomon & Schrum, 2007). This study investigated the use of web 2.0 tools in the largest 14 high schools in Montana with a student population of 900 or more, and identified relationships that influenced the integration of the tools into the science classroom. Montana science teachers …

The Genetic Basis Of Fitness: Detecting Inbreeding Depression And Selective Sweeps In Bighorn Sheep, Martin Dennis Kardos

Graduate Student Theses, Dissertations, & Professional Papers

Understanding the fitness effects of inbreeding is a crucial and long standing goal in conservation and evolutionary biology. Many studies measure individual inbreeding (F, the proportion of genome that is identical by descent) and its fitness effects using either pedigrees or molecular markers. Knowing which genes most strongly affect fitness can help to explain why some individuals outperform others, and elucidate the mechanisms of inbreeding depression and adaptation. However, identifying adaptive genes is difficult in most species because of limited genomic resources.

I used simulations to evaluate the performance of marker- and pedigree-based measures of F and inbreeding depression. I …

Ecology Of Juvenile Salmon In Large Floodplain Rivers: The Influence Of Habitat Modification By Beavers (Castor Canadensis) On Salmon Growth And Production, Rachel Lanelle Malison

Graduate Student Theses, Dissertations, & Professional Papers

I investigated the influence of beavers on aquatic floodplain habitats and determined how juvenile salmon habitat use, growth, survival, movement, and production varied by habitat type in a large alluvial floodplain of the Kwethluk River in western Alaska. I also compared juvenile salmon production at the floodplain scale in the Kwethluk River (with beavers), to a very similar salmon river in Kamchatka (the Kol) that has no beavers.

Beavers modified 87.5% of the aquatic off-channel habitat of the Kwethluk River, which was composed of three successional stages of beaver ponds (early-, mid-, and latesuccessional), and beaver-influenced spring brooks. Early-successional ponds …

Interactions Between Arenavirus Proteins And Small Molecule Inhibitors Of Infection, Emily L. Messina

Graduate Student Theses, Dissertations, & Professional Papers

Arenaviruses are globally distributed, negative-sense, single-stranded RNA viruses which persist in specific rodent host species. Of the 32 known arenaviruses, 10 have been associated with human disease. Of these, Lassa, Junín, Machupo, Guanarito, and Sabia viruses cause severe hemorrhagic fevers. The only current option for the treatment of arenavirus infection is the off-label use of ribavirin. However, ribavirin is associated with severe side effects. Clearly, there exists a need for the study of arenavirus biology and of novel drugs for the treatment of arenaviral infection. My work focused on two attractive targets for inhibition of infection: the arenaviral RNA-dependent RNA …

Psychological Adjustment And Relational Development In Ethiopian Adoptees And Their Families, Waganesh Zeleke

Graduate Student Theses, Dissertations, & Professional Papers

The number of American families choosing to adopt a child from Ethiopia has increased exponentially since 2004. Over the past five years alone, between 2006 and 2011, 13.5% of internationally adopted children in the U.S. came from Ethiopia. The purpose of this study was to examine psychological adjustment and relational development of Ethiopian adoptees who have been adopted during 2007 -2010 and their families who reside in Montana.

Using a convenience-sampling method, data were collected from 25 adoptive parents who adopted a total of 35 children from Ethiopia. All families live in Montana and responded to questions through an online …

Applications Of Autonomous Ph And Pco2 Sensors To Study Inorganic Carbon Dynamics In A Coastal Upwelling System, Katherine Elizabeth Harris

Graduate Student Theses, Dissertations, & Professional Papers

Submersible Autonomous Moored Instruments for pH and pCO2 (SAMI-pH and SAMI-CO2) were deployed in a coastal upwelling zone on the Oregon Coast to collect unique multi-season, multi-year datasets of carbonate system dynamics. This is the first long-term deployment of the SAMI-pH paired with a SAMI-CO2. The objectives of this study included (1) improving the accuracy of the SAMI-pH (2) assessing the performance of using paired SAMI-pH and SAMI-CO2 measurements to calculate other carbonate system parameters and (3) analyzing the data to better understand the seasonal, inter-annual, and upwelling variation in the coastal marine carbonate system. SAMI-pH accuracy was improved by …

Hydrologic Conditions And Streamflow Change In An Evolving Semi-Arid Agricultural Watershed, Smith River, Montana, Andrea Stanley

Graduate Student Theses, Dissertations, & Professional Papers

Agricultural land and water use has modified natural flow regimes in the western US. Understanding the effect of agricultural water use on streamflow is critical to effective water management and is often limited by the available data record. This investigation evaluates agricultural water use and streamflow in the Smith River watershed (SRW), a semi-arid agricultural watershed located on the eastern slope of the northern Rocky Mountains in west-central Montana. Questions motivating this study include: (1) Has agricultural water use modified streamflow on the Smith River? (2) What aspect of agricultural activity in the Smith River watershed is having the greatest …

Spatial Distribution And Quantification Of Forest Treatment Residues For Bioenergy Production, Lucas A. Wells

Graduate Student Theses, Dissertations, & Professional Papers

The availability and spatial distribution of forest treatment residues are prerequisites to supply chain development for bioenergy production. To accurately estimate potential residue quantities, data must be provided to simulate stand-level silviculture across the landscape of interest. However, biomass utilization assessments often consider broad regions where adequate data are not supplied. At present, these measures are addressed using strategic level assessments and broad-based management that may not be applicable to all areas of the landscape. This thesis introduces a new methodology for spatially describing stand-level treatment residue quantities based on detailed silvicultural prescriptions and site specific management. Using National Agricultural …

Evaluating Genetic Status And Management Tradeoffs For Conservation Of Cutthroat Trout (Oncorhynchus Clarkii), Kellie Jahan Carim

Graduate Student Theses, Dissertations, & Professional Papers

Habitat fragmentation and invasive species are two of the primary threats to global biodiversity, yet biologists have tested few guidelines for protecting species under these conditions. These threats are particularly relevant to conservation of freshwater species like the Cutthroat Trout (Oncorhynchus clarkii). Hybridization with introduced Rainbow Trout (O. mykiss) has already caused extinction of one subspecies and threatens extant populations. Additionally, Cutthroat populations have lost genetic diversity across their range due to habitat destruction and fragmentation. These threats create a catch-22 for managers, wherein treating one problem (connecting populations) may lead to the other (interactions with invasive species). Furthermore, little …