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Item 1, 8-naphthyridine copper complexes(Montana State University - Bozeman, College of Letters & Science, 1968) Enwall, Eric LeeItem 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 15 kV class underground cable fault tester(Montana State University - Bozeman, College of Engineering, 1999) Nystrom, Clair KarlItem 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 18-beta-glycyrrhetinic acid and methicillin resistant Staphylococcus aureus : from lytic activity to reduced pathogenesis(Montana State University - Bozeman, College of Agriculture, 2012) Long, Danyelle Renee; Chairperson, Graduate Committee: Jovanka Voyich-Kane; Julia Meade, Jay Hendricks, Michele E. Hardy and Jovanka M. Voyich were co-authors of the article, '18-beta-glycyrrhetinic acid inhibits MRSA survival and attenuates virulence gene expression' in the journal 'Antimicrobial agents and chemotherapy' which is contained within this thesis.Methicillin-resistant Staphylococcus aureus (MRSA) is Gram-positive pathogen known to cause severe disease in humans. MRSA's resistance to the beta-lactam class of antibiotics makes it an increasing healthcare concern. Over the last two decades there has been a rise in the incidence of community-associated MRSA, specifically pulsed-field gel electrophoresis type USA300 (known to cause severe skin and soft tissue infections). The development of drug therapies against MRSA infections that do not induce resistance and have efficacy against MRSA is a pressing matter. In this study, we investigate the potential of two components in licorice extracts, Glycyrrhizic acid (GA) and 18-beta-Glycyrrhetinic acid (GRA), as effective antimicrobials against MRSA. Using in vitro survival assays, we determined that GRA is directly bactericidal to MRSA. Using a murine model of skin and soft tissue infection, we discovered that topical treatment with GRA reduced severity of MRSA skin and soft tissue infections more rapidly than treatment with GA or a control. The increase in infection clearance was not due to a reduction in bacterial burden, but results indicate that GRA may decrease severity of the infection via an effect on the immune system. Treatment of an MRSA skin infection with GRA reduced expression of KC and G-CSF. To further investigate how GRA treatment led to a more rapid clearance of infection, we analyzed the expression of five S. aureus virulence genes (saeR, hla, RNAIII transcript, mecA, and sbi) after treatment with GRA or GA. GRA rapidly down-regulated four of the five virulence genes in vitro and all five virulence genes in vivo in the skin infection model. The data presented here shows that GRA is bactericidal, assists in decreasing the severity of MRSA infection via down-regulation of virulence genes, and can induce an altered immune response in the host.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 1952 Montana elections : politics as usual(Montana State University - Bozeman, College of Letters & Science, 1976) Everett, David DeanItem 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 The 1985 NCAA financial audit legislation : is it working, from college and university presidents' perspective ?(Montana State University - Bozeman, College of Education, Health & Human Development, 1992) Gibson, Thomas HarrisonItem 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 1H, 13C, 15N backbone and side chain NMR resonance assignments of the N-terminal NEAr iron transporter domain 1 (NEAT 1) of the hemoglobin receptor IsdB of Staphylococcus aureus(2014-04) Fonner, Brittany A.; Tripet, Brian P.; Lui, Mengyao; Zhu, Hui; Lei, Benfang; Copie, ValerieStaphylococcus aureus is an opportunistic pathogen that causes skin and severe infections in mammals. Critical to S. aureus growth is its ability to scavenge iron from host cells. To this effect, S. aureus has evolved a sophisticated pathway to acquire heme from hemoglobin (Hb) as a preferred iron source. The pathway is comprised of nine iron-regulated surface determinant (Isd) proteins involved in heme capture, transport, and degradation. A key protein of the heme acquisition pathway is the surface-anchored hemoglobin receptor protein IsdB, which is comprised of two NEAr transporter (NEAT) domains that act in concert to bind Hb and extract heme for subsequent transfer to downstream acquisition pathway proteins. Despite significant advances in the structural knowledge of other Isd proteins, the structural mechanisms and molecular basis of the IsdB-mediated heme acquisition process are not well understood. In order to provide more insights into the mode of function of IsdB, we have initiated NMR structural studies of the first NEAT domain of IsdB (IsdBN1). Herein, we report the near complete 1H, 13C and 15N resonance assignments of backbone and side chain atoms, and the secondary structural topology of the 148-residue IsdB NEAT 1 domain. The NMR results are consistent with the presence of eight β-strands and one α-helix characteristic of an immunoglobulin-like fold observed in other NEAT domain family proteins. This work provides a solid framework to obtain atomic-level insights toward understanding how IsdB mediates IsdB-Hb protein–protein interactions critical for heme capture and transfer.Item 2-Arylacetamido-4-phenylamino-5-substituted pyridazinones as formyl peptide receptors agonists(2016-06) Vergelli, Claudia; Schepetkin, Igor A.; Ciciani, Giovanna; Cilibrizzi, Agostino; Crocetti, Letizia; Giovannoni, Maria Paola; Guerrini, Gabriella; Iacovone, Antonella; Kirpotina, Liliya N.; Khlebnikov, Andrei I.; Ye, Richard D.; Quinn, Mark T.N-Formyl peptide receptors (FPRs: FPR1, FPR2, and FPR3) are G protein-coupled receptors that play key roles in modulating immune cells. FPRs represent potentially important therapeutic targets for the development of drugs that could enhance endogenous anti-inflammation systems associated with various pathologies, thereby reducing the progression of inflammatory conditions. Previously, we identified 2-arylacetamide pyridazin-3(2H)-ones as FPR1- or FPR2-selective agonists, as well as a large number of FPR1/FPR2-dual agonists and several mixed-agonists for the three FPR isoforms. Here, we report a new series of 2-arylacetamido-4-aniline pyridazin-3(2H)-ones substituted in position 5 as a further development of these FPR agonists. Chemical manipulation presented in this work resulted in mixed FPR agonists 8a, 13a and 27b, which had EC50 values in nanomolar range. In particular, compound 8a showed a preference for FPR1 (EC50 =45nM), while 13a and 27b showed a moderate preference for FPR2 (EC50 =35 and 61nM, respectively). Thus, these compounds may represent valuable tools for studying FPR activation and signaling.Item A 20,000-yr-old record of vegetation and climate from Lower Red Rock Lake, Centennial Valley, Southwestern Montana(Montana State University - Bozeman, College of Letters & Science, 2010) Mumma, Stephanie Ann; Chairperson, Graduate Committee: Cathy WhitlockA ca. 20,000-yr-old sediment core from Lower Red Rock Lake (LRRL) in the Centennial Valley of southwest Montana was obtained to reconstruct the vegetation, climate, and environmental changes during and following the late-Pinedale Glaciation in the northern Rocky Mountains. The base of core LRRL 06P49 consisted of inorganic silt and clay, deposited when a large glacial lake occupied the eastern Centennial Valley. The glacial lake receded during the late-glacial period when its western outlet stabilized. Prior to 17,000 cal yr BP, high pollen percentages of Juniperus, Poaceae, Asteraceae, and other herbs as well as low pollen accumulation rates suggest cold dry conditions. The sparsely vegetated landscape at LRRL is consistent with paleoclimate model simulations that show southward displacement of the jet stream and a strong glacial anticyclone during the full-glacial period. Between 17,000 and 10,500 cal yr BP, increases in Picea and Abies pollen percentages suggest a shift to subalpine parkland and warmer conditions than before as result of the northward shift of the jet stream and increasing summer insolation. From 10,500 to 7100 cal yr BP, pollen percentages of Picea and Abies decreased and those of xerophytic taxa (e.g., Chenopodiaceae and Pseudotsuga) increased, suggesting development of steppe and open forest. Warmer drier conditions in the early Holocene were likely a response to increased summer insolation and a strengthened Pacific subtropical high-pressure system. From 7100 to 2400 cal yr BP, cooler and moister conditions at LRRL, driven by decreasing summer insolation, led to the expansion of high-elevation conifers, steppe, and wetlands. Increases in Picea and Abies pollen percentages after 2400 cal yr BP indicate further closing of forests at high elevations and even cooler and wetter conditions than before. Examination of the first arrival of Pseudotsuga in pollen records throughout the region shows that its arrival was later at sites on the Atlantic side of the Continental Divide as compared to sites on the Pacific side. The geographic pattern suggests that the Continental Divide posed a topographic or climate barrier in the late-glacial period, delaying the migration of Pseudotsuga menziesii from glacial refugia.Item A 200-year history of arctic and alpine fungi in North America: Early sailing expeditions to the molecular era(2020) Noffsinger, Chance; Cripps, Cathy L.; Horak, EgonMushrooms and other fleshy fungi are important components of arctic and alpine habitats where they enhance nutrient uptake in plants and replenish poor soils through decomposition. Here we assemble the 200-year (1819–2019) record of their discovery in North America, beginning with early Arctic sailing expeditions, followed by intense taxonomic studies, and concluding with the molecular era, all of which highlight the difficulty of exhaustively revealing their biodiversity in these extreme, cold-dominated habitats. Compiled biogeographic data reveal that a majority of arctic fungi have large intercontinental distributions with disjunct alpine populations. A newly compiled checklist of 170 species of Basidiomycota in fifty-one genera and twenty families in the Rocky Mountain alpine zone provides current baseline data prior to expected environmental shifts.Item 2001 Canola Variety and Hybrid Performance Evaluations(Central Agricultural Research Center, 2001) Wichman, David M.; Sharp, Gail L.This report evaluates the relative yield performance of spring canola varieties adapted to the northern plains and intermountain regions. Emergence was slow and very erratic due to dry weather conditions that persisted till early June at both locations. The Moore site was very slow to emerge with much of the emergence occurring in early June. Tyler seeded with a hoe drill and more uniform and much earlier emergence. The delayed emergence contributed to low yield levels at both locations. Extremely high levels of evaporative demand in July were also detrimental to the canola trial yields (See Tables sc35 and sc36). The Moccasin trials were further impacted by ground sparrows and Cashin finch feeding on the seed pods prior and during ripening. Intermountain 223 RR and 357 RR lines were top performers in both trials. These lines have been good performers other years as well. Late seeding and unusually dry weather with high evaporative demand resulted below average canola yields. The variation within the study due to factors other than the characteristics of the varieties themselves reduced the value of both variety evaluation nurseries.Item 2001 Cereal Forage Species, Variety and Seeding Rate Studies(Central Agricultural Research Center, 2001) Wichman, David M.; Vavrovsky, Joe; Sharp, Gail L.; Cash, S.D.; Johnson, D.; Hensleigh, Pat F.; Hybner, Roger M.; Carr, P.This report determines the forage production potential of spring and winter cereal grain species and varieties under dryland conditions in central Montana. Determine the optimum spring cereal seeding rates for maximum forage production. Cereal forage yields were respectable considering the low precipitation levels received over the past year. Fall 2000 and early spring seeded crops on tilled soils experienced severe and multiple soil blasting and seedling burial. Therefore, the data presented here is not sufficient to make extensive inferences or comparisons amongst varieties or species.Item 2001 Evaluation of Non-Alfalfa Perennial Legumes(Central Agricultural Research Center, 2001) Wichman, David M.; Vavrovsky, Joe; Cash, S.D.; Ditterline, R. L.This report determines yield levels of modern varieties non-bloat causing perennial forage legumes: sainfoin, birdsfoot trefoil, and cicer milkvetch relative to yields of alfalfa check varieties. Dry weather and other droughty conditions have been hard on the non-bloat causing perennial legumes. In 2001, alfalfa entries have proved to be superior in dry matter yield production than the entries of sainfoin, birdsfoot trefoil, and cicer milkvetch. There appears to be some difference between varieties, for forage yield, with in each of species (See Tables F 5 &F 6). Due to the unusually dry weather the past couple of years, hopefully it remains classified as “unusually dry” rather than the beginning of a new norm, it is best not to make any conjectures about relative yield levels of the various varieties.Item 2001 Montana Intra-State Alfalfa Variety Trials(Central Agricultural Research Center, 2001) Wichman, David M.; Vavrovsky, Joe; Cash, S.D.; Ditterline, R. L.; Sharp, Gail L.This report identifies superior alfalfa varieties for dryland forage production in central Montana. Yield results for alfalfa variety nurseries seeded in the years 2001, 2000, 1998, and 1997 are presented in tables 1, 2, 3, and 4, respectively. Drought conditions persisting since the spring of 1997 continue to depress alfalfa forage yields. Warm winter weather which allow perennials, such as alfalfa, to remain actively growing through the late fall, winter and or early spring cause the plants to deplete soil water reserves while producing little vegetation. Yield levels are one third to one fourth of the expected yields. No significant variations in disease infections or insect feedings have been observed. Little variation in plot/treatment ranking across years has been observed. This indicates the importance of getting a good stand to start with. Ladak 65 yield levels continue to be similar to those of more modern varieties which have greater disease resistance. However, recent years have been dry and unsuitable for outstanding yield levels. In better yield conditions, this researcher expects modern varieties to exhibit a higher yield level relative to Ladak 65.