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Item Functional traits underlie specialist-generalist strategies in whitebark pine and limber pine(Elsevier BV, 2023-08) Ulrich, Danielle E. M.; Wasteneys, Chloe; Hoy-Skubik, Sean; Alongi, FranklinPlant species life history strategies are described by functional variation spanning an acquisitive and conservative resource use continuum. Specialist species can exhibit traits promoting one end of the continuum, while generalist species can display traits promoting both acquisitive and conservative resource use. Whitebark pine (Pinus albicaulis, PIAL) and limber pine (Pinus flexilis, PIFL) are two high-elevation pines that have similar growth and morphology, yet contrasting elevational distributions with PIAL viewed as a specialist inhabiting a narrower elevation range, and PIFL as a generalist inhabiting a broader elevation range. We compared the physiological and morphological traits of greenhouse-grown 5-year-old PIAL and PIFL. Our results suggest that PIFL’s acquisitive and conservative resource use traits contribute to its generalist strategy and ability to inhabit a greater range of elevations than PIAL. PIFL had greater acquisitive resource use traits including: high-light tolerance (greater Qsat, greater fascicle density), increased biomass allocation to photosynthetic tissue (higher needle biomass, aboveground:belowground biomass, needle:branch + stem biomass), and higher C and water uptake (greater stomatal density and size, higher C assimilation rate), as well as greater conservative resource use traits including: greater physical stress resistance (shorter height, higher stem and branch diameters, greater branch and stem diameter:length), drought tolerance (higher SWC, leaf starch proportion), and drought avoidance (earlier budburst phenology, smaller hydroscape area) than PIAL. Our results suggest that PIFL may make more efficient use of high-light loads and maximize C and water uptake when moisture is abundant during spring snowmelt before the onset of dry summer conditions. Other conservative resource use traits describing cold tolerance, heat tolerance, and drought tolerance did not differ between species, suggesting that both species exhibit traits that promote similar conservative resource use enabling their overlapping persistence at higher elevations. Comparing the physiology of PIAL and PIFL within the same environment enables us to identify physiological mechanisms that underlie species establishment and survival, and how juvenile physiology contributes to their contrasting distributions and their generalist-specialist strategies.Item How does the use of the anatomage table impact student learning of anatomy and physiology concepts?(Montana State University - Bozeman, College of Letters & Science, 2021) Keegan, Emily; Chairperson, Graduate Committee: Greg FrancisAnatomy and Physiology is a class that relies heavily on visual models. In this study, the use of the Anatomage table was used during the skeletal system and muscular system units. A comparison group did not use the table for their lab in the first unit, and an experimental group used the table. During the second unit, the groups switched so that all students got to experience working with the table in at least one unit. Pre and post-test data, surveys, interviews, and retention tests were used as data collection tools. The results suggest that the Anatomage table has benefits for some students, especially in identifying and applying the knowledge acquired in the units. It had less of an impact on written test scores, especially in higher achieving students.Item An expansion of nonlethal tools for use on juvenile pallid sturgeon in the upper basin of the Missouri River(Montana State University - Bozeman, College of Letters & Science, 2020) Djokic, Matea Asahi; Chairperson, Graduate Committee: Christine Verhille; Kevin Kappenman, Joshua Heishman, Kezia Manlove and Christine Verhille were co-authors of the article, 'Investigations and implications of blood biochemistry, energetic reserves, and visual assessments to assess hatchery-reared juvenile pallid sturgeon health' which is contained within this thesis.; Kevin Kappenman, Joshua Heishman, T. Gibson Gaylord and Christine Verhille were co-authors of the article, 'An assessment of the distell fatmeter for use in juvenile pallid sturgeon (Scaphirhynchus albus)' submitted to the journal 'Transactions of the American Fisheries Society' which is contained within this thesis.Pallid sturgeon (Scaphirhynchus albus) are an endangered species endemic to the Missouri and Mississippi drainages in North America. Mitigation activities including conservation spawning and stocking programs were implemented to prevent extinction of the species. Monitoring of growth, survival, and condition are conducted annually to determine efficacy of managerial efforts to recover pallid sturgeon. My thesis aimed to establish a knowledge base of juvenile pallid sturgeon physiological bioindicators that can supplement field monitoring of growth, size, and condition measurements. Ultimately, I aimed to resolve mechanisms underlying population fluctuations (e.g. growth rate) caused by environmental changes or management actions. Fisheries managers have observed reduced growth rates of recently stocked hatchery origin pallid sturgeon (HOPS) relative to earlier cohorts. Based on high survival rates of historic stocked HOPS, some fisheries biologists hypothesize that growth rates of recent HOPS cohorts reflect compensatory density dependence in growth caused by overstocking. However, size, growth, and condition metrics commonly tracked on wild-captured sturgeon cannot assess underlying mechanisms driving trends in population growth rate. The purpose of this hatchery-based research was to explore nonlethal physiological measurements to expand the toolset available to managers to assess the status of physiological processes within HOPS that may reflect ecosystem effects on these fish. I investigated a suite of physiological bioindicators that could reflect key physiological processes (nutrition, tissue damage, and chronic stress) expected to respond to common ecosystem stressors. I determined reference intervals for 13 blood biochemical analytes on a population of healthy hatchery-reared juvenile pallid sturgeon (n = 41). Inter-individual variation in blood biochemical analytes and five additional physiological variables were analyzed to determine composite variables predictive of growth. To investigate nonlethal tools to quantify whole-body energetic reserves of juvenile pallid sturgeon, I determined best-fit predictive models to estimate whole-body energy (df = 33; R 2 = 0.40; p < 0.001) and lipid (df = 33, R 2 = 0.45, p < 0.001) content using Distell Fatmeter and mass measurements. Research presented in this thesis aims to provide a preliminary understanding of expected ranges of various physiological bioindicators and methods for nonlethally measuring these bioindicators in hatchery-reared juvenile pallid sturgeon.Item Recent and historical water use strategies of western U.S. conifers(Montana State University - Bozeman, College of Letters & Science, 2017) Clute, Timothy; Chairperson, Graduate Committee: David Roberts; Jia Hu (co-chair); Jia Hu was a co-author of the article, 'Investigating the variation in inter- and intraspecific physiological plant hydraulic traits across an elevation gradient' which is contained within this thesis.; Jia Hu was a co-author of the article, 'Historic influence of climate on conifer water status in northwestern Montana' which is contained within this thesis.Understanding the physiological traits that trees utilize to manage water use can reveal important insights into how and why they occur in their realized habitat. Among the tools to investigate these traits include measuring trees' seasonal water status, deciphering trees' rooting depth, and measuring the trees' vulnerability to cavitation. However, it is equally important to understand how complex landscape heterogeneity will affect both the inter- and intraspecific variation of these physiological traits. This thesis seeks to quantify the variation of the physiological traits used to manage water status among three common Rocky Mountain conifers; Pseudotsuga menziesii (a plastic species occurring across xeric and mesic sites), Pinus ponderosa (a xeric species), and Picea engelmannii (a mesic species), occurring across an elevation gradient. Furthermore, it aims to link tree maintenance of water status to source water, and understand how the importance of source water is reflected in the tree ring record. In the first chapter, I sought to quantify inter- and intraspecific variation of these three species by measuring diurnal and seasonal water status, seasonal water use, and xylem vulnerability to cavitation at a low elevation xeric site, composed of P. ponderosa and P. menziesii, and a high elevation mesic site, composed of P. engelmannii and P. menziesii. We found good evidence for interspecific variation in the physiological traits to manage water status at both sites. However, we did not find strong evidence for intraspecific variation in these same traits within our plastic species (P. menziesii). In the second chapter, we investigated how stable isotopes in tree rings reflected seasonal source water use as well as the atmospheric conditions the trees were growing under. At the low elevation site, we found evidence that the tree ring isotopes were likely reflecting both seasonal precipitation inputs as well as the atmospheric growing conditions. At the high elevation site, trees likely only reflected the atmospheric growing conditions and did not reflect seasonal water use.Item Statistical methodology for biological signals in the presence of measurement uncertainty(Montana State University - Bozeman, College of Letters & Science, 2018) Barbour, Christopher Robert; Chairperson, Graduate Committee: Mark Greenwood; Bibiana Bielekova (co-chair); Mark Greenwood, Dominique Zosso and Bibiana Bielekova were co-authors of the article, 'Constructed composite response: a framework for constructing targeted latent variables' submitted to the journal 'Biometrika' which is contained within this dissertation.; Christopher Barbour, Mark Greenwood, Dominique Zosso and Bibiana Bielekova were co-authors of the article, 'Extending CCR methodology to high-dimensional data to develop a sensitive clinical endpoint for multiple sclerosis' submitted to the journal 'Computational and graphical statistics' which is contained within this dissertation.; Peter Kosa, Mika Komori, Makoto Tanigaw, Ruturaj Masvekar, Tianxia Wu, Kory Johnson, Panagiotis Douvaras, Valentina Fossati, Ronald Herbst, Yue Wang, Keith Tan, Mark Greenwood and Bibiana Bielekova were co-authors of the article, 'Molecular-based diagnosis of multiple sclerosis and its progressive stage' in the journal 'Annals of neurology' which is contained within this dissertation.In recent years, increasing amounts of complex biological data are being collected on patients in many branches of medical research. Many of these signals are being collected with a certain amount of imprecision in the attained measurements. Two such areas in multiple sclerosis (MS) research are clinical scale development and proteomics analysis. Scales are often constructed from multiple outcome measures to create a combined metric that is a better measure of the true trait of interest than any of the original components. When the interest is in creating a scale that is sensitive to changes over time, developing it using cross-sectional data may not tune the projection to detect changes over time optimally. The proposed methodology, coined the Constructed Composite Response (CCR), was developed to maximize detected longitudinal change. A simulation study, and analysis of a motivating dataset, demonstrated that the CCR methodology performs better at capturing longitudinal change than traditional techniques. Including sparsifying constraints, motivated by penalized regression models, improved the performance of the CCR in high- dimensional data. In proteomics data, undesirable sources of variation are often present. Examples include temporal fluctuation in control samples and technical variability from multiple assay runs. When developing a molecular classifier of MS, a novel variable screening procedure was implemented to eliminate proteins with high levels of these unwanted sources. A simulation study compared this with traditional screening approaches and findings are discussed. Future extensions and directions of research are also discussed.Item Radical S-adenosyl-L-methionine enzymes: radical control and assembly of complex metallocofactors(Montana State University - Bozeman, College of Letters & Science, 2018) Byer, Amanda Shaw; Chairperson, Graduate Committee: Joan B. Broderick; Elizabeth C. McDaniel, Stella Impano, William E. Broderick and Joan B. Broderick were co-authors of the article, 'Mechanistic studies of radical SAM enzymes: pyruvate formate-lyase activating enzyme and lysine 2,3-aminomutase' in the journal 'Methods in enzymology' which is contained within this dissertation.; Masaki Horitani was an author and Krista A. Shisler, Tilak Chandra, Joan B. Broderick and Brian M. Hoffman were co-authors of the article, 'Why nature uses radical S-adenosyl-L-methionine enzymes so widely: electron nuclear double resonance studies of lysine 2,3-aminomutase show the 5'-dADO 'free radical' is never free' in the journal 'Journal of the American Chemical Society' which is contained within this dissertation.; Hao Yang, Elizabeth C. McDaniel, Venkatesian Kathiresan, Stella Impano, Adrien Pagnier, Hope Watts, Carly Denler, Anna Vagstad, Jorn Piel, Kaitlin S. Duschene, Eric M. Shepard, Thomas P. Shields, Lincoln G. Scott, Edward A. Lilla, Kenichi Yokoyama, William E. Broderick, Brian M. Hoffman, and Joan B. Broderick were co-authors of the article, 'New paradigm for radical SAM enzyme reactions: organometallic intermediate Omega is central to catalysis' in the journal 'Journal of the American Chemical Society' which is contained within this dissertation.; Eric M. Shepard was an author and Priyanka Aggarwal, Jeremiah N. Betz, Krista A. Shisler, Robert J. Usselman, Gareth R. Eaton, Sandra S. Eaton, Joan B. Broderick were co-authors of the article, 'Hydrogenase maturase HydF: insights into [2Fe-2S] and [4Fe-4S] cluster communication and hydrogenase activation' in the journal 'Biochemistry' which is contained within this dissertation.; Eric M. Shepard, William E. Broderick and Joan B. Broderick were co-authors of the article, 'Activation of [FeFe]-hydrogenase in the absence of HydG' which is contained within this dissertation.; Donald S. Wright, Michael W. Ratzloff, Yisong Guo, Paul W. King and Joan B. Broderick were co-authors of the article, '[FeFe]-hydrogenase metallocluster assmebly on HydF as influenced by HydG' which is contained within this dissertation.; Amanda Shaw Byer is not the main author of an article which is contained within this dissertation.Electrons, whether from carbon-based radicals or metals, can generate oxidative stress and disease in biological systems; however, when directed properly by a protein, these electrons are responsible for crucial life-sustaining reactions, including photosynthesis, oxygen transport in blood, and nitrogen fixation. Beneficial use of radicals and metallocofactors is abundant in nature, and both are essential in one of the largest superfamilies in biology - the radical SAM (RS) enzyme superfamily. Found in all kingdoms of life, RS enzymes contribute to critical processes such as DNA repair, complex metallocluster assembly, and vitamin synthesis. Understanding how metalloenzymes, such as RS enzymes, control electron flow is critical for comprehending biological system functionality and potentially improving productivity through rational design. This work examines radical control in RS enzyme mechanism and then expands scope to consider RS enzyme contribution to assembly of the complex metallocluster (Hcluster) of [FeFe]-hydrogenase. Focusing in on the fundamental chemistry of RS enzyme radical initiation, this work investigated intermediate states in 5'deoxyadenosyl radical formation by: 1) slowing the radical reaction with a SAM analogue, anSAM, and 2) swiftly stopping catalysis via rapid freeze quench techniques. Employing primarily EPR and ENDOR spectroscopies, two intermediate states were characterized: 1) an analogue of the 5'-deoxyadenosyl radical, formed from anSAM, and 2) an organometallic intermediate, Omega, formed during reaction with SAM. To probe how certain RS enzymes (HydE and HydG) contribute to build the 2Fe H-cluster subcluster precursor on the [FeFe]-hydrogenase scaffold HydF, FeS cluster intermediate states were analyzed using UV-Vis, EPR, FTIR, CD, Mossbauer spectroscopies and gas chromatography. These results demonstrate: 1) HydF initially binds a [4Fe-4S] and a [2Fe-2S] cluster, 2) HydG contributes small molecule diatomics and perturbs the [2Fe-2S] cluster environment, 3) HydE can generate a subcluster precursor on HydF capable of generating catalytically active HydA, and 4) the HydF dimer, not tetramer, delivers the 2Fe H-cluster subcluster precursor for activation. Collectively, this thesis illuminates key mechanistic states RS enzymes use to productively control the 5'deoxyadenosyl radical during catalysis and identifies [FeFe]-hydrogenase H-cluster precursor intermediates suggesting RS enzyme sequentiality.Item An analysis of hands-on medical experience and student engagement in the science classroom(Montana State University - Bozeman, College of Letters & Science, 2019) Wood, Jerilyn J.; Chairperson, Graduate Committee: Greg FrancisOver a period of six months, students in the Chinook anatomy and physiology class learned EMT training skill and completed work-based learning experiences, such as job shadowing, in order to increase engagement in the science classroom. This project also looked at the impact that this hands-on learning had on students' confidence and feelings of preparedness as well as their desire to pursue a career in the medical field. Students completed a pre- and post-treatment engagement surveys and post-treatment interviews. From the surveys, it was found that there was no statistical difference between the pre- and post-treatment survey responses. The raw data showed some shifts in students' attitudes but there was not enough change to be statistically significant. From the post-treatment interviews, students reported feeling more engaged and better able to make connections between the material learned in class and the real-world. They also reported developing skills that would help them succeed beyond high school such as time management and responsibility for their own learning.Item Memorization strategies for anatomy and physiology(Montana State University - Bozeman, College of Letters & Science, 2019) Selle, Michelle Lynn; Chairperson, Graduate Committee: Greg FrancisThe ability for students to have a deep understanding of the material in anatomy and physiology stems from having a solid foundation of lower-level learning skills of the material at hand. One of the key lower-learning skills that allows students the ability to tap into the higher-level thinking is memorization. This does not refer to basic rote memorization, but memorization that can actually help to link neural connections and bring a greater depth of knowledge into the anatomy classroom. This study will investigate whether detailed instruction on three memorization techniques targeting multimodal learners impacts students' short-term and long-term memory, ultimately impacting depth of understanding in the anatomy/physiology classroom. The study will also explore student attitudes, mainly in reference to their confidence and stress levels, in regards to the memorization strategies taught.Item Misconception probes in human anatomy and physiology(Montana State University - Bozeman, College of Letters & Science, 2019) Quinton, Murvyn Scott; Chairperson, Graduate Committee: Greg FrancisLearning is a process of acquiring knowledge and understanding. When students enter the classroom, they bring their current knowledge and understanding with them. Teachers build upon this knowledge to move students toward new levels of comprehension. The problem is that in many cases, students bring incorrect information or misconceptions into the classroom. When teachers add more upon these concepts, the students often end up with a blending of the correct and inaccurate information. Misconception probes are a tool that requires students to address these problematic concepts and allow teachers to identify the specific misconceptions that students have so that they can be corrected. This study investigated how the use of misconception probes would affect students in a science classroom. Specifically, the areas investigated were the impacts on learning and achievement and the impact on student confidence. Students were given misconception probes that focused on problem concepts within the selected unit, and then remedial instruction was given to address the misconceptions. Performance on the unit exams did not show a significant change; however, some students showed a marked decrease. Student metacognitive awareness of what they did and did not know increased. This resulted in students providing more accurate assessments of their confidence on the surveys given before the exams. This action research showed that misconception probes can be a valuable tool to help inform the teacher and to help students to recognize where their understanding is lacking.Item The effects of L-citrulline supplementation on physical performance(Montana State University - Bozeman, College of Education, Health & Human Development, 2019) Stordahl, Peter Lawrence; Chairperson, Graduate Committee: John G. Seifert; John G. Seifert, Mary Miles and Dawn Tarabochia were co-authors of the article, 'The effects of l-citrulline supplementation on physical performance' submitted to the journal 'Journal of strength and conditioning research' which is contained within this thesis.INTRODUCTION. Recent studies have investigated l-citrulline (CIT) as a possible ergogenic aid. A small number of studies have explored the performance question, with varying methodologies and results. The purpose of this study was to examine CIT influence on cycling time to exhaustion, cardiovascular function, and muscle activity. METHODS. Thirteen healthy subjects volunteered for this study. The first visit was to obtain a maximal power output, where 80% and 50% of maximal power were calculated for the following two visits. Subjects were then randomly assigned into either treatment or placebo groups for the second visit and the opposite treatment for the third visit. Subjects were instructed to drink their treatment 1 hour prior to coming into the laboratory. The treatment drink contained 10g of CIT while the placebo (PBO) was formulated to look and taste like the CIT drink. The second and third visits to the laboratory consisted of EMG from the rectus femoris, vastus medialis, and medial gastrocnemius of the right leg, along with HR monitor and BP. Subjects completed a 40-minute interval ride, consisting of 8 5-minute intervals of 3 minutes at 50% maximal power and 2-minutes at 80% maximal power. After the interval ride, subjects received a second dose of either treatment, 5g of CIT or PBO and were allowed 1-hour rest before the ramped time to exhaustion (TTE) test. RESULTS. There was no significant difference in TTE by treatment (CIT, 20.79 + or - 4.48 and PBO, 20.86 + or - 3.99). There was no significant main effect of treatment on percent of maximum heart rate (p = 0.084), mean arterial pressure (p = 0.714), or muscle activity of the rectus femoris (p =0.300), vastus medialis (p = 0.641), or medial gastrocnemius (p = 0.133) during the TTE test. CONCLUSIONS. There were no differences in cycling TTE between treatments. Further research should investigate the metabolism of CIT under different physiological conditions.