College of Letters & Science
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The College of Letters and Science, the largest center for learning, teaching and research at Montana State University, offers students an excellent liberal arts and sciences education in nearly 50 majors, 25 minors and over 25 graduate degrees within the four areas of the humanities, natural sciences, mathematics and social sciences.
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Item 133 Cs NMR Study of the Ferroelectric and Antiferroelectric Transitions in CsH 2 PO 4(1991-05-01) Schuele, Paul J.; Schmidt, V. HugoPressure and temperature effects on the one dimensional (1D) and higher-dimensionality correlations associated with the ferroelectric (FE) and antiferroelectric (AFE) phase transitions in cesium dihydrogen phosphate were studied using 133Cs nuclear magnetic resonance at 6.5 MHz. The spin-latticerelaxation time T1 was measured at temperatures down to the FE Curie point TC at pressures of 1 bar and at 1.5 and 3.0 kbar, down to the triple point Tt = 124.6 K at 3.3 kbar, and down to the AFE Neel point TN at 3.6 kbar. Far from the transition T1 decreases exponentially with decreasing temperature due to 1D fluctuations associated with the Jb interactions in disordered hydrogen-bonded chains running along the b axis. As temperature is decreased further, T1 decreases linearly as the JC interaction between hydrogen-bonded chains in b-c planes becomes important. From these results the pressure dependences of Jb, JC and the interplanar interaction Ja were calculated. At 3.3 kbar Ja changes sign, so the stacking of ordered planes becomes AFE rather than FE. At pressures above about 9 kbar, where the interaction JC extrapolates to zero, a new AFE phase is predicted in which each b-axis chain is oriented AFE with respect to nearest neighbors in both the a and c directions.Item 17O NQR Study of the Antiferroelectric Phase Transition in TlH2PO4(1988) Seliger, J.; Zagar, V.; Blinc, Robert; Schmidt, V. HugoThe temperature dependence of the 1 7O NQR spectra in TlH2PO4 has been measured using a proton‐1 7 O nuclear quadrupole double resonance technique. The results show that the protons in the short one‐dimensionally linked O1–H1‐‐O1 and O2–H2‐‐O2hydrogen bonds are moving between two equilibrium sites above T c and freeze into one of the off‐center sites below T c . The protons in the asymmetric O3–H3‐‐O4hydrogen bonds are static and ordered above and below T c .Item 18β-Glycyrrhetinic Acid Induces Metabolic Changes and Reduces Staphylococcus aureus Bacterial Cell-to-Cell Interactions(MDPI AG, 2022-06) Weaver, Alan J.; Borgogna, Timothy R.; O’Shea-Stone, Galen; Peters, Tami R.; Copié, Valérie; Voyich, Jovanka; Teintze, MartinThe rise in bacterial resistance to common antibiotics has raised an increased need for alternative treatment strategies. The natural antibacterial product, 18β-glycyrrhetinic acid (GRA) has shown efficacy against community-associated methicillin-resistant Staphylococcus aureus (MRSA), although its interactions against planktonic and biofilm modes of growth remain poorly understood. This investigation utilized biochemical and metabolic approaches to further elucidate the effects of GRA on MRSA. Prolonged exposure of planktonic MRSA cell cultures to GRA resulted in increased production of staphyloxanthin, a pigment known to exhibit antioxidant and membrane-stabilizing functions. Then, 1D 1H NMR analyses of intracellular metabolite extracts from MRSA treated with GRA revealed significant changes in intracellular polar metabolite profiles, including increased levels of succinate and citrate, and significant reductions in several amino acids, including branch chain amino acids. These changes reflect the MRSA response to GRA exposure, including potentially altering its membrane composition, which consumes branched chain amino acids and leads to significant energy expenditure. Although GRA itself had no significant effect of biofilm viability, it seems to be an effective biofilm disruptor. This may be related to interference with cell–cell aggregation, as treatment of planktonic MRSA cultures with GRA leads to a significant reduction in micro-aggregation. The dispersive nature of GRA on MRSA biofilms may prove valuable for treatment of such infections and could be used to increase susceptibility to complementary antibiotic therapeutics.Item The 1972 Montana State Constitution--its provision for Montana Indians : a promise unfulfilled(Montana State University - Bozeman, 1981) Eschler, Leonard EdwardItem A 1975 catalog of alternate and free secondary schools in Montana(Montana State University - Bozeman, 1975) Lithander, Sherry Lee MillerItem 1982–2010 Trends of Light Use Efficiency and Inherent Water Use Efficiency in African vegetation: Sensitivity to Climate and Atmospheric CO2 Concentrations(MDPI, 2014) Traore, Abdoul Khadre; Ciais, Philippe; Vuichard, Nicolas; McBean, Natasha; Dardel, Cecile; Poulter, Benjamin; Piao, Shilong; Fisher, Joshua; Viovy, Nicolas; Jung, Martin; Myneni, Ranga B.Light and water use by vegetation at the ecosystem level, are key components for understanding the carbon and water cycles particularly in regions with high climate variability and dry climates such as Africa. The objective of this study is to examine recent trends over the last 30 years in Light Use Efficiency (LUE) and inherent Water Use Efficiency (iWUE*) for the major biomes of Africa, including their sensitivities to climate and CO2. LUE and iWUE* trends are analyzed using a combination of NOAA-AVHRR NDVI3g and fAPAR3g, and a data-driven model of monthly evapotranspiration and Gross Primary Productivity (based on flux tower measurements and remote sensing fAPAR, yet with no flux tower data in Africa) and the ORCHIDEE (ORganizing Carbon and Hydrology In Dynamic EcosystEms) process-based land surface model driven by variable CO2 and two different gridded climate fields. The iWUE* data product increases by 10%–20% per decade during the 1982–2010 period over the northern savannas (due to positive trend of vegetation productivity) and the central African forest (due to positive trend of vapor pressure deficit). In contrast to the iWUE*, the LUE trends are not statistically significant. The process-based model simulations only show a positive linear trend in iWUE* and LUE over the central African forest. Additionally, factorial model simulations were conducted to attribute trends in iWUE and LUE to climate change and rising CO2 concentrations. We found that the increase of atmospheric CO2 by 52.8 ppm during the period of study explains 30%–50% of the increase in iWUE* and >90% of the LUE trend over the central African forest. The modeled iWUE* trend exhibits a high sensitivity to the climate forcing and environmental conditions, whereas the LUE trend has a smaller sensitivity to the selected climate forcing.Item 1H NMR based metabolic profiling distinguishes the differential impact of capture techniques on wild bighorn sheep(Springer Science and Business Media LLC, 2021-05) O’Shea-Stone, Galen; Lambert, Rachelle; Tripet, Brian; Berardinelli, James; Thomson, Jennifer; Copié, Valérie; Garrott, RobertEnvironmental metabolomics has the potential to facilitate the establishment of a new suite of tools for assessing the physiological status of important wildlife species. A first step in developing such tools is to evaluate the impacts of various capture techniques on metabolic profiles as capture is necessary to obtain the biological samples required for assays. This study employed 1H nuclear magnetic resonance (NMR)-based metabolite profiling of 562 blood serum samples from wild bighorn sheep to identify characteristic molecular serum makers of three capture techniques (dart, dropnet, and helicopter-based captures) to inform future sampling protocols for metabolomics studies, and to provide insights into the physiological impacts of capture. We found that different capture techniques induce distinct changes in amino acid serum profiles, the urea cycle, and glycolysis, and attribute the differences in metabolic patterns to differences in physical activity and stress caused by the different capture methods. These results suggest that when designing experiments involving the capture of wild animals, it may be prudent to employ a single capture technique to reduce confounding factors. Our results also supports administration of tranquilizers as soon as animals are restrained to mitigate short-term physiological and metabolic responses when using pursuit and physical restraint capture techniques.Item 2017 Montana Climate Assessment: Stakeholder driven, science informed(Montana Institute on Ecosystems, 2017-09) Whitlock, Cathy; Cross, Wyatt F.; Maxwell, Bruce D.; Silverman, Nick; Wade, Alisa A.The Montana Climate Assessment (MCA) is an effort to synthesize, evaluate, and share credible and relevant scientific information about climate change in Montana with the citizens of the State. The motivation for the MCA arose from citizens and organizations in Montana who have expressed interest in receiving timely and pertinent information about climate change, including information about historical variability, past trends, and projections of future impacts as they relate to topics of economic concern.This first assessment reports on climate trends and their consequences for three of Montana’s vital sectors: water, forests, and agriculture. We consider the MCA to be a sustained effort. We plan to regularly incorporate new scientific information, cover other topics important to the people of Montana, and address the needs of the state.Item 75As nuclear quadrupole resonance in weakly substitutionally disordered Rb1‑x(NH4)xH2AsO4(1994-07-11) Papantopoulos, G.; Papavassiliou, G.; Milia, F.; Schmidt, V. Hugo; Drumheller, John E.; Pinto, Nicholas J.; Blinc, Robert; Zalar, B.Item A dependable distance estimator to black hole low-mass X-ray binaries(Oxford University Press, 2024-03) Abdulghani, Y.; Lohfink, A. M.; Chauhan, J.Black Hole Low Mass X-ray Binaries (BH-LMXBs) are excellent observational laboratories for studying many open questions in accretion physics. However, determining the physical properties of BH-LMXBs necessitates knowing their distances. With the increased discovery rate of BH-LMXBs, many canonical methods cannot produce accurate distance estimates at the desired pace. In this study, we develop a versatile statistical framework to obtain robust distance estimates soon after discovery. Our framework builds on previous methods where the soft spectral state and the soft-to-hard spectral state transitions, typically present in an outbursting BH-LMXB, are used to place constraints on mass and distance. We further develop the traditional framework by incorporating general relativistic corrections, accounting for spectral/physical parameter uncertainties, and employing assumptions grounded in current theoretical and observational knowledge. We tested our framework by analyzing a sample of 50 BH-LMXB sources using X-ray spectral data from the Swift/XRT, MAXI/GSC, and RXTE/PCA missions. By modeling their spectra, we applied our framework to 26 sources from the 50. Comparison of our estimated distances to previous distance estimates indicates that our findings are dependable and in agreement with the accurate estimates obtained through parallax and H i absorption methods. Investigating the accuracy of our constraints, we have found that estimates obtained using both the soft and transition spectral information have a median uncertainty (1σ) of 20%, while estimates obtained using only the soft spectral state spectrum have a median uncertainty (1σ) of around 50%. Furthermore, we have found no instrument-specific biases.Item A framework to link climate change, food security, and migration: unpacking the agricultural pathway(Springer Science and Business Media LLC, 2024-03) Tuholske, Cascade; Di Landro, Maria Agustina; Anderson, Weston; van Duijne, Robbin Jan; de Sherbinin, AlexResearchers have long hypothesized linkages between climate change, food security, and migration in low- and middle-income countries (LMICs). One such hypothesis is the “agricultural pathway,” which postulates that negative climate change impacts on food production harm livelihoods, which triggers rural out-migration, internally or abroad. Migration is thus an adaptation to cope with the impacts of climate change and bolster livelihoods. Recent evidence suggests that the agriculture pathway is a plausible mechanism to explain climate-related migration. But direct causal connections from climate impacts on food production to livelihood loss to rural out-migration have yet to be fully established. To guide future research on the climate-food-migration nexus, we present a conceptual framework that outlines the components and linkages underpinning the agricultural pathway in LMICs. We build on established environmental-migration conceptual frameworks that have informed empirical research and deepened our understanding of complex human-environmental systems. First, we provide an overview of the conceptual framework and its connection to the agricultural pathway hypothesis in the climate mobility literature. We then outline the primary components and linkages of the conceptual framework as they pertain to LMIC contexts, highlighting current research gaps and challenges relating to the agricultural pathway. Last, we discuss possible future research directions for the climate-food-migration nexus. By highlighting the complex, multiscale, interconnected linkages that underpin the agricultural pathway, our framework unpacks the multiple causal connections that currently lie hidden in the agricultural pathway hypothesis.Item A-site strontium doping effects on structure, magnetic, and photovoltaic properties of (Bi 1-x Sr x )FeO 3-δ multiferroic ceramics(2015) Tu, Chi-Shun; Xu, Zhe-Rui; Schmidt, V. Hugo; Chan, T.-S.; Chien, R. R.; Son, H.Raman spectroscopy, X-ray diffraction (XRD), magnetization hysteresis loop, synchrotron X-ray absorption spectroscopy, and photovoltaic effects have been measured in (Bi1−xSrx)FeO3−δ (BFO100xSr) ceramics for x=0.0, 0.05, 0.10, and 0.15. Raman spectra and XRD reveal a rhombohedral R3c structure in all compounds. A-site Sr2+ doping increases fluctuations in cation-site occupancy and causes broadening in Raman modes. BFO15Sr exhibits a strong ferromagnetic feature due to reduction of FeOFe bond angle evidenced by the extended synchrotron X-ray absorption fine structure. The heterostructure of indium tin oxide (ITO) film/(Bi1−xSrx)FeO3−δ ceramic/Au film exhibit clear photovoltaic (PV) responses under blue illumination of λ=405 nm. The maximal power-conversion efficiency and external quantum efficiency in ITO/BFO5Sr/Au are about 0.004% and 0.2%, respectively. A model based on optically excited charges in the depletion region between ITO and (Bi1−xSrx)FeO3−δ can well describe open-circuit voltage and short-circuit current as a function of illumination intensity.Item A-site strontium doping effects on structure, magnetic, and photovoltaic properties of (Bi1−xSrx)FeO3−δ multiferroic ceramics(2015-03) Tu, Chi-Shun; Xu, Zhe-Rui; Schmidt, V. Hugo; Chan, Ting-Shan; Chien, R.R.; Son, HyungbinRaman spectroscopy, X-ray diffraction (XRD), magnetization hysteresis loop, synchrotron X-ray absorption spectroscopy, and photovoltaic effects have been measured in (Bi1−xSrx)FeO3−δ (BFO100xSr) ceramics for x=0.0, 0.05, 0.10, and 0.15. Raman spectra and XRD reveal a rhombohedral R3c structure in all compounds. A-site Sr2+ doping increases fluctuations in cation-site occupancy and causes broadening in Raman modes. BFO15Sr exhibits a strong ferromagnetic feature due to reduction of Fesingle bondOsingle bondFe bond angle evidenced by the extended synchrotron X-ray absorption fine structure. The heterostructure of indium tin oxide (ITO) film/(Bi1−xSrx)FeO3−δ ceramic/Au film exhibit clear photovoltaic (PV) responses under blue illumination of λ=405 nm. The maximal power-conversion efficiency and external quantum efficiency in ITO/BFO5Sr/Au are about 0.004% and 0.2%, respectively. A model based on optically excited charges in the depletion region between ITO and (Bi1−xSrx)FeO3−δ can well describe open-circuit voltage and short-circuit current as a function of illumination intensity.Item Ability to benefit : a credible basis for admissions to tribally controlled colleges(Montana State University - Bozeman, College of Education, Health & Human Development, 1991) Boham, Sandra LeeItem Absarog-Issawua (from the land of the Crow Indians)(Montana State University - Bozeman, 1970) Toineeta, Joy Yellowtail"This is an original piece of research into the Crow Indian uses of native plants and animals for food and medicinal, as well as other purposes. Incorporated into the manuscript are introductory legends or incidents surrounding or accompanying the recipes."Item Absent autonomy: Relational competence and gendered paths to faculty self-determination in the promotion and tenure process(2018-09) Skewes, Monica C.; Shanahan, Elizabeth A.; Smith, Jessi L.; Honea, Joy C.; Belou, Rebecca M.; Rushing, Sara; Intemann, Kristen; Handley, Ian M.This research examines ways in which men and women university faculty sought self-determination in the promotion and tenure (P&T) process. Self-Determination Theory (SDT; Deci & Ryan, 2012) research tends to view autonomy as the central factor in self-determination, taking priority over other psychological needs of relatedness and competence. The P&T process occurs within a context that inherently limits autonomy, providing a unique opportunity to examine experiences of relatedness and competence when autonomy is constrained. We used a qualitative research strategy with a matched case study design to explore how individuals experience the constructs of SDT (i.e., autonomy, competence, and relatedness) within the P&T process. Our project focuses on faculty in science, technology, engineering, and mathematics (STEM) departments undergoing P&T review at one university. Women faculty in STEM were compared with men faculty at the same rank and in similar departments concurrently going through P&T review. Findings showed that men reported experiencing self-determination via informational competence whereas women approached self-determination through relational competence. Creating a level playing field for faculty navigating the P&T process requires being attuned to different paths to self-determination, fostering relationships between faculty, and clarifying policies and procedures.Item AC Susceptibility of Biased One-Dimensional Stochastic Ising Model.(1971-06) Schmidt, V. HugoThe ac susceptibility for the one‐dimensional Ising model is obtained for arbitrary coupling strength in the presence of a dc bias field strong enough to align most of the dipoles in one direction. The dipole flip probability is assumed proportional to the Boltzmann factor corresponding to half the energy change resulting from the flip. The general expression for ac susceptibility is analyzed in three limiting cases: weak coupling with strong bias, strong coupling with strong bias, and strong coupling with weak bias. In the latter case, relatively long chains of anti‐aligned dipoles exist and give rise to large susceptibility.Item Accelerated Gibbs sampling of normal distributions using matrix splittings and polynomials(2017-11) Fox, Colin; Parker, Albert E.Standard Gibbs sampling applied to a multivariate normal distribution with a specified precision matrix is equivalent in fundamental ways to the Gauss Seidel iterative solution of linear equations in the precision matrix. Specifically, the iteration operators, the conditions under which convergence occurs, and geometric convergence factors (and rates) are identical. These results hold for arbitrary matrix splittings from classical iterative methods in numerical linear algebra giving easy access to mature results in that field, including existing convergence results for antithetic-variable Gibbs sampling, REGS sampling, and generalizations. Hence, efficient deterministic stationary relaxation schemes lead to efficient generalizations of Gibbs sampling. The technique of polynomial acceleration that significantly improves the convergence rate of an iterative solver derived from a symmetric matrix splitting may be applied to accelerate the equivalent generalized Gibbs sampler. Identicality of error polynomials guarantees convergence of the inhomogeneous Markov chain, while equality of convergence factors ensures that the optimal solver leads to the optimal sampler. Numerical examples are presented, including a Chebyshev accelerated SSOR Gibbs sampler applied to a stylized demonstration of low-level Bayesian image reconstruction in a large 3-dimensional linear inverse problem.Item Access to Power or Genuine Empowerment? An Analysis of Three Community Forest Groups in Nepal(Society for Human Ecology, 2004) Lachapelle, Paul; Smith, Patrick D.; McCool, SFThe introduction of community forestry in Nepal represents an attempt to decentralize control and instill democratic reform in the management of forest resources through the direct involvement of individuals in decision making and benefit sharing. Detailed analyses of community forest outcomes, specifically an understanding of the process of self-governance and the exercise of power, remains a critical gap. Using a purposive sampling methodology, we identified 38 forest users representing a diversity of interests in three communities of the middle hills of Nepal and conducted in-depth interviews focusing on perceptions of an ability to exercise power in forest management. Power in this context is defined as the ability to create rules, make decisions, enforce compliance and adjudicate disputes. Our results identify inferiority, vulnerability, and a lack of transparency as factors that keep forest users from exercising power. We conclude that while community forestry offers tremendous potential to practice self-governance, the behavior of individuals based on complex informal institutional arrangements, such as caste and gender, must be accounted for in such formalized policy initiatives. Opportunities to influence power through mandated processes alone fail to fully explain or affect the potential for community forestry. Instead, we note that genuine empowerment is related to capacities involving the skills and confidence necessary to exercise power.Item An accumulation of turtle eggs with embryos from the Campanian (Upper Cretaceous) Judith River Formation of Montana(2017-01) Lawver, Daniel R.; Jackson, Frankie D.A weathered accumulation of turtle eggs, interpreted as remnants of a single clutch composed of at least 16 turtle eggs (MOR 710) from the Campanian (Upper Cretaceous) Judith River Formation of north-central Montana, USA, represents a new oospecies Testudoolithus zelenitskyae. This ootaxon is diagnosed by the following unique combination of characters: spherical eggs 34–39 mm in diameter, 660–760 μm thick eggshell, shell unit height-to-width ratio of 3.15:1–5.5:1, and domed shell units. Estimated egg mass indicates that the egg-laying adult likely possessed a carapace 35.0–54.4 cm in length. Similarities between T. zelenitskyae oosp. nov. and Adocus sp. eggs, along with comparable body size, suggest that this taxon might have produced MOR 710. One egg exhibits abnormal multilayered eggshell, likely resulting from prolonged egg retention by the female turtle. At least five of these eggs, including the multilayered specimen, preserve embryonic remains that demonstrate a late stage of embryonic development. This suggests that death occurred just prior to hatching.