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• 11. [Article] Climate Change Effects on Arbuscular Mycorrhizal Fungi and Prairie Plants Along a Mediterranean Climate Gradient

  Arbuscular mycorrhizal fungi (AMF) provide numerous services to their plant symbionts. Understanding the effects of climate change on AMF, and the resulting plant responses, is a crucial factor in predicting ...

  Citation × Citation Citation Abstract Copy Title: Climate Change Effects on Arbuscular Mycorrhizal Fungi and Prairie Plants Along a Mediterranean Climate Gradient Author: Wilson, Hannah Year: 2013 Arbuscular mycorrhizal fungi (AMF) provide numerous services to their plant symbionts. Understanding the effects of climate change on AMF, and the resulting plant responses, is a crucial factor in predicting ecosystem responses on a global scale. We used a manipulative climate change experiment embedded within a natural climate gradient in Oregon and Washington to examine how the effects of future climate change on AMF-plant symbioses are mediated by soil water availability, soil nutrient availability, and vegetation dynamics. Using structural equation modeling, we found that the direct effect of increasing temperatures was to decrease AMF colonization. Indirect effects of temperature, mediated through other variables, canceled each other out. However, future shifts in these relationships could either exacerbate or mitigate the negative direct effect of temperature. As ecosystems in Mediterranean climates experience more intense droughts and heavier rains, decreases in AMF colonization could have substantial consequences for plant communities and ecosystem function. Title: Climate Change Effects on Arbuscular Mycorrhizal Fungi and Prairie Plants Along a Mediterranean Climate Gradient Author: Wilson, Hannah Year: 2013 Arbuscular mycorrhizal fungi (AMF) provide numerous services to their plant symbionts. Understanding the effects of climate change on AMF, and the resulting plant responses, is a crucial factor in predicting ecosystem responses on a global scale. We used a manipulative climate change experiment embedded within a natural climate gradient in Oregon and Washington to examine how the effects of future climate change on AMF-plant symbioses are mediated by soil water availability, soil nutrient availability, and vegetation dynamics. Using structural equation modeling, we found that the direct effect of increasing temperatures was to decrease AMF colonization. Indirect effects of temperature, mediated through other variables, canceled each other out. However, future shifts in these relationships could either exacerbate or mitigate the negative direct effect of temperature. As ecosystems in Mediterranean climates experience more intense droughts and heavier rains, decreases in AMF colonization could have substantial consequences for plant communities and ecosystem function. Close

• 12. [Article] Measuring the Effects of Parking Lots and Tree Shading on Microscale Urban Heat Islands

  55 pages. A thesis presented to the Department of Planning, Public Policy, and Management and the Clark Honors College of the University of Oregon in partial fulfillment of the requirements for degree ...

  Citation × Citation Citation Abstract Copy Title: Measuring the Effects of Parking Lots and Tree Shading on Microscale Urban Heat Islands Author: Goodrich, Elliot Year: 2016 55 pages. A thesis presented to the Department of Planning, Public Policy, and Management and the Clark Honors College of the University of Oregon in partial fulfillment of the requirements for degree of Bachelor of Arts, Winter 2016. Title: Measuring the Effects of Parking Lots and Tree Shading on Microscale Urban Heat Islands Author: Goodrich, Elliot Year: 2016 55 pages. A thesis presented to the Department of Planning, Public Policy, and Management and the Clark Honors College of the University of Oregon in partial fulfillment of the requirements for degree of Bachelor of Arts, Winter 2016. Close

• 13. [Article] Experimental Insights into the Formation of High-Mg Andesites in the Trans-Mexican Volcanic Belt

  x, 86 p. : ill. A print copy of this thesis is available through the UO Libraries. Search the library catalog for the location and call number.

  Citation × Citation Citation Abstract Copy Title: Experimental Insights into the Formation of High-Mg Andesites in the Trans-Mexican Volcanic Belt Author: Weber, Rachel Maria, 1975- Year: 2011, 2010 x, 86 p. : ill. A print copy of this thesis is available through the UO Libraries. Search the library catalog for the location and call number. Title: Experimental Insights into the Formation of High-Mg Andesites in the Trans-Mexican Volcanic Belt Author: Weber, Rachel Maria, 1975- Year: 2011, 2010 x, 86 p. : ill. A print copy of this thesis is available through the UO Libraries. Search the library catalog for the location and call number. Close

• 14. [Article] The Neurodevelopmental and Genetic Basis to Natural Variation in Thermal Preference Behavior in Caenorhabditis elegans

  In a heterogeneous environment where temperature influences fitness, individuals must navigate to a thermal optimum to maximize reproductive output and minimize physiological stress. However, the optimal ...

  Citation × Citation Citation Abstract Copy Title: The Neurodevelopmental and Genetic Basis to Natural Variation in Thermal Preference Behavior in Caenorhabditis elegans Author: Gaertner, Bryn Year: 2012, 2014 In a heterogeneous environment where temperature influences fitness, individuals must navigate to a thermal optimum to maximize reproductive output and minimize physiological stress. However, the optimal temperature varies among individuals due to genetic and environmental contributions. The neural and genetic basis to such natural variation in behavior has remained elusive in most cases, as the high-throughput genomic, neurodevelopmental, and behavioral techniques were not developed. Using the nematode Title: The Neurodevelopmental and Genetic Basis to Natural Variation in Thermal Preference Behavior in Caenorhabditis elegans Author: Gaertner, Bryn Year: 2012, 2014 In a heterogeneous environment where temperature influences fitness, individuals must navigate to a thermal optimum to maximize reproductive output and minimize physiological stress. However, the optimal temperature varies among individuals due to genetic and environmental contributions. The neural and genetic basis to such natural variation in behavior has remained elusive in most cases, as the high-throughput genomic, neurodevelopmental, and behavioral techniques were not developed. Using the nematode Close

• 15. [Article] Effects of food levels and temperature on growth and hemocyanin ontogeny in the juvenile Dungeness crab, Cancer magister

  Typescript. Includes vita and abstract. Bibliography: Includes bibliographical references (leaves 54-60). Description: xi, 60 leaves : ill. ; 29 cm.

  Citation × Citation Citation Abstract Copy Title: Effects of food levels and temperature on growth and hemocyanin ontogeny in the juvenile Dungeness crab, Cancer magister Author: Dumler, Karen Lynn Year: 2009, 1996 Typescript. Includes vita and abstract. Bibliography: Includes bibliographical references (leaves 54-60). Description: xi, 60 leaves : ill. ; 29 cm. Title: Effects of food levels and temperature on growth and hemocyanin ontogeny in the juvenile Dungeness crab, Cancer magister Author: Dumler, Karen Lynn Year: 2009, 1996 Typescript. Includes vita and abstract. Bibliography: Includes bibliographical references (leaves 54-60). Description: xi, 60 leaves : ill. ; 29 cm. Close

• 16. [Article] The role of sulfur alloying in defects and transitions in copper indium gallium diselenide disulfide thin films

  xv, 132 p. : ill. A print copy of this title is available from the UO Libraries, under the call number: SCIENCE TK7871.15.F5 H325 2007

  Citation × Citation Citation Abstract Copy Title: The role of sulfur alloying in defects and transitions in copper indium gallium diselenide disulfide thin films Author: Halverson, Adam Fraser, 1978- Year: 2008, 2007 xv, 132 p. : ill. A print copy of this title is available from the UO Libraries, under the call number: SCIENCE TK7871.15.F5 H325 2007 Title: The role of sulfur alloying in defects and transitions in copper indium gallium diselenide disulfide thin films Author: Halverson, Adam Fraser, 1978- Year: 2008, 2007 xv, 132 p. : ill. A print copy of this title is available from the UO Libraries, under the call number: SCIENCE TK7871.15.F5 H325 2007 Close

• 17. [Article] Vibrational Sum Frequency Spectroscopic Investigations of Sulfur Dioxide Adsorption to Atmospherically Relevant Aqueous Surfaces

  xv, 108 p. : ill. (chiefly col.)

  Citation × Citation Citation Abstract Copy Title: Vibrational Sum Frequency Spectroscopic Investigations of Sulfur Dioxide Adsorption to Atmospherically Relevant Aqueous Surfaces Author: Ota, Stephanie Tomoko, 1978- Year: 2011 xv, 108 p. : ill. (chiefly col.) Title: Vibrational Sum Frequency Spectroscopic Investigations of Sulfur Dioxide Adsorption to Atmospherically Relevant Aqueous Surfaces Author: Ota, Stephanie Tomoko, 1978- Year: 2011 xv, 108 p. : ill. (chiefly col.) Close

• 18. [Article] Effects of salinity and temperature on the respiratory physiology of the Dungeness crab, Cancer magister, during development

  Typescript. Includes vita and abstract. Bibliography: Includes bibliographical references (leaves 172-183).

  Citation × Citation Citation Abstract Copy Title: Effects of salinity and temperature on the respiratory physiology of the Dungeness crab, Cancer magister, during development Author: Brown, Anne Christine, 1962- Year: 2009, 1991 Typescript. Includes vita and abstract. Bibliography: Includes bibliographical references (leaves 172-183). Title: Effects of salinity and temperature on the respiratory physiology of the Dungeness crab, Cancer magister, during development Author: Brown, Anne Christine, 1962- Year: 2009, 1991 Typescript. Includes vita and abstract. Bibliography: Includes bibliographical references (leaves 172-183). Close

• 19. [Article] Theoretical Study of Spin-wave Effects in Quantum Ferromagnets

  In this dissertation, we examine quantum ferromagnets and determine various effects of the magnetic Goldstone modes or "magnons'' in these systems. Firstly, we calculate the magnon contribution to the ...

  Citation × Citation Citation Abstract Copy Title: Theoretical Study of Spin-wave Effects in Quantum Ferromagnets Author: Bharadwaj, Sripoorna Paniyadi Krishna Year: 2017 In this dissertation, we examine quantum ferromagnets and determine various effects of the magnetic Goldstone modes or "magnons'' in these systems. Firstly, we calculate the magnon contribution to the transport relaxation rate of conduction electrons in metallic ferromagnets and find that at asymptotically low temperatures, the contribution behaves as T^2 exp(-T_0/T) and not as T^2 predicted previously. To perform these calculations, we derive and use a very general effective theory for metallic ferromagnets. This activation barrier-like behavior is due to the fact that spin waves only couple electrons from different Stoner subbands that arise from the splitting of the conduction band in presence of a nonzero magnetization. The T^2 behavior is found to be valid only in a pre-asymptotic temperature window. The temperature scale T_0 is the energy of the least energetic ferromagnon that couples electrons of different spins. Second, we discuss magnon-induced long-range correlation functions in quantum magnets. In the ordered phases of both classical ferromagnets and antiferromagnets, the long-range correlations induced by the magnons lead to a singular wavenumber dependence of the longitudinal order-parameter susceptibility in spatial dimensions 2<d<4. We investigate the quantum analog of this singularity using a nonlinear sigma model. In a quantum antiferromagnet at $T=0$, a weaker nonanalytic behavior is obtained, which is consistent with power counting. The analogous result for a quantum ferromagnet is absent if the magnon damping is neglected. This is due to the lack of magnon number fluctuations in the quantum ferromagnetic ground state. Magnon damping due to quenched disorder restores the expected nonanalyticity. Finally, we use an effective field theory for clean, strongly interacting electron systems to calculate the magnon contribution to the density of states, the longitudinal magnetic susceptibility and the conductivity in an itinerant ferromagnet. Utilizing a loop expansion that does not assume the electron-electron interaction to be a small parameter, we obtain the leading nonanalytic corrections to the Stoner saddle-point results for these observables, as functions of the frequency and wavenumber in the hydrodynamic limit. The dissertation includes previously published and unpublished co-authored material. Title: Theoretical Study of Spin-wave Effects in Quantum Ferromagnets Author: Bharadwaj, Sripoorna Paniyadi Krishna Year: 2017 In this dissertation, we examine quantum ferromagnets and determine various effects of the magnetic Goldstone modes or "magnons'' in these systems. Firstly, we calculate the magnon contribution to the transport relaxation rate of conduction electrons in metallic ferromagnets and find that at asymptotically low temperatures, the contribution behaves as T^2 exp(-T_0/T) and not as T^2 predicted previously. To perform these calculations, we derive and use a very general effective theory for metallic ferromagnets. This activation barrier-like behavior is due to the fact that spin waves only couple electrons from different Stoner subbands that arise from the splitting of the conduction band in presence of a nonzero magnetization. The T^2 behavior is found to be valid only in a pre-asymptotic temperature window. The temperature scale T_0 is the energy of the least energetic ferromagnon that couples electrons of different spins. Second, we discuss magnon-induced long-range correlation functions in quantum magnets. In the ordered phases of both classical ferromagnets and antiferromagnets, the long-range correlations induced by the magnons lead to a singular wavenumber dependence of the longitudinal order-parameter susceptibility in spatial dimensions 2<d<4. We investigate the quantum analog of this singularity using a nonlinear sigma model. In a quantum antiferromagnet at $T=0$, a weaker nonanalytic behavior is obtained, which is consistent with power counting. The analogous result for a quantum ferromagnet is absent if the magnon damping is neglected. This is due to the lack of magnon number fluctuations in the quantum ferromagnetic ground state. Magnon damping due to quenched disorder restores the expected nonanalyticity. Finally, we use an effective field theory for clean, strongly interacting electron systems to calculate the magnon contribution to the density of states, the longitudinal magnetic susceptibility and the conductivity in an itinerant ferromagnet. Utilizing a loop expansion that does not assume the electron-electron interaction to be a small parameter, we obtain the leading nonanalytic corrections to the Stoner saddle-point results for these observables, as functions of the frequency and wavenumber in the hydrodynamic limit. The dissertation includes previously published and unpublished co-authored material. Close

• 20. [Article] Timing Vapor–Melt Equilibration in Silicic Magmas

  Magmas experiencing pressure changes can follow equilibrium or nonequilibrium degassing paths that determine the rate of gas exsolution and the composition of gases exsolved. Many variables influence timescales ...

  Citation × Citation Citation Abstract Copy Title: Timing Vapor–Melt Equilibration in Silicic Magmas Author: Ball, Madison Year: 2017 Magmas experiencing pressure changes can follow equilibrium or nonequilibrium degassing paths that determine the rate of gas exsolution and the composition of gases exsolved. Many variables influence timescales of equilibration between vapor and melt after a perturbation in pressure, temperature, or other factors, and the magnitude of this equilibration time determines whether the system experiences equilibrium degassing or not. In order to create a simplified framework for assessing degassing regime, we constructed a numerical diffusion model to test the sensitivity of equilibration time to variables such as bubble size, spacing, melt temperature, initial and final system pressures, and water content. We then determined the degassing regime for a range of bubble-spacing and decompression rates as an initial simplified framework to build on. We also attempted the first mixed-volatile continuous decompression experiments in order validate our model and further improve analyses and interpretations of volatile gradients in natural samples. Title: Timing Vapor–Melt Equilibration in Silicic Magmas Author: Ball, Madison Year: 2017 Magmas experiencing pressure changes can follow equilibrium or nonequilibrium degassing paths that determine the rate of gas exsolution and the composition of gases exsolved. Many variables influence timescales of equilibration between vapor and melt after a perturbation in pressure, temperature, or other factors, and the magnitude of this equilibration time determines whether the system experiences equilibrium degassing or not. In order to create a simplified framework for assessing degassing regime, we constructed a numerical diffusion model to test the sensitivity of equilibration time to variables such as bubble size, spacing, melt temperature, initial and final system pressures, and water content. We then determined the degassing regime for a range of bubble-spacing and decompression rates as an initial simplified framework to build on. We also attempted the first mixed-volatile continuous decompression experiments in order validate our model and further improve analyses and interpretations of volatile gradients in natural samples. Close