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Full-Text Articles in Physical Sciences and Mathematics

Beetles, Fungi And Trees: A Story For The Ages? Modeling And Projecting The Multipartite Symbiosis Between The Mountain Pine Beetle, Dendroctonus Ponderosae, And Its Fungal Symbionts, Grosmannia Clavigera And Ophiostoma Montium, Audrey L. Addison May 2014

Beetles, Fungi And Trees: A Story For The Ages? Modeling And Projecting The Multipartite Symbiosis Between The Mountain Pine Beetle, Dendroctonus Ponderosae, And Its Fungal Symbionts, Grosmannia Clavigera And Ophiostoma Montium, Audrey L. Addison

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

As data collection and modeling improve, ecologists increasingly discover that interspecies dynamics greatly affect the success of individual species. Models accounting for the dynamics of multiple species are becoming more important. In this work, we explore the relationship between mountain pine beetle (MPB, Dendroctonus ponderosae Hopkins) and two mutualistic fungi, Grosmannia clavigera and Ophiostoma montium. These species are involved in a multipartite symbiosis, critical to the survival of MPB, in which each species benefits.

Extensive phenological modeling has been done to determine how temperature affects the timing of life events and cold-weather mortality of MPB. The fungi have also …


Soil Water Flux Estimates From Streaming Potential And Penta-Needle Heat Pulse Probe Measurements, Pawel J. Szafruga May 2014

Soil Water Flux Estimates From Streaming Potential And Penta-Needle Heat Pulse Probe Measurements, Pawel J. Szafruga

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Growing populations, coupled with climate change and resource depletion, have heightened concern about water management. The growing need to better manage agricultural systems, including irrigation and fertilizer application, as well the lasting consequences of excess application of nitrogen and other nutrients, could be remedied with an improved method to monitor soil water movement. Despite huge technological advances, a tool to measure soil water flow at the low rates found in the field has not been developed. Current methods lack the precision to provide the needed accuracy to fully understand soil-water dynamics, as well as the ability to provide instantaneous information. …


Computational Models Of Intracellular And Intercellular Processes In Developmental Biology, Ahmadreza Ghaffarizadeh May 2014

Computational Models Of Intracellular And Intercellular Processes In Developmental Biology, Ahmadreza Ghaffarizadeh

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Systems biology takes a holistic approach to biological questions as it applies mathematical modeling to link and understand the interaction of components in complex biological systems. Multiscale modeling is the only method that can fully accomplish this aim. Mutliscale models consider processes at different levels that are coupled within the modeling framework. A first requirement in creating such models is a clear understanding of processes that operate at each level. This research focuses on modeling aspects of biological development as a complex process that occurs at many scales. Two of these scales were considered in this work: cellular differentiation, the …


Linking Montane Soil Moisture Measurements To Evapotranspiration Using Inverse Numerical Modeling, Ling Lv May 2014

Linking Montane Soil Moisture Measurements To Evapotranspiration Using Inverse Numerical Modeling, Ling Lv

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Evapotranspiration (ET) and soil moisture play important roles in annual water delivered from snowpack to reservoirs, lakes and streams. Indeed, ET and soil moisture are key factors dictating the performance of the regional climate models in the intermountain west (IMW) of the USA. Water resources management and climate modeling require accurate prediction of ET and areal soil moisture for reliable estimates of ongoing and future water needs. This research has examined ways to estimate ET from four common vegetation types in the IMW (aspen, conifer, grass and sage) using local soil moisture measurements from an advanced instrumentation network located in …


The Human Dimensions Of Climate Change: Smallholder Perception And Adaptation In The Loess Plateau Region Of China, Morey Burnham May 2014

The Human Dimensions Of Climate Change: Smallholder Perception And Adaptation In The Loess Plateau Region Of China, Morey Burnham

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Climate change poses problems for agriculture in the Global South. Smallholders in the Global South are often considered highly vulnerable to climate change as a result of their farms being located in marginal environments, their insecure land tenure and lack of technology, and their participation in unpredictable regional and world markets. Analyzing how smallholders perceive climate change and attendant risk, the factors that enable and constrain their adaptive capacity, and the social impacts of state led projects designed to mitigate the impacts of climate change may provide crucial insights for developing effective climate adaption projects and policies. This research examined …


Fault And Fluid Interactions In The Elsinore Fault-West Salton Detachment Fault Damage Zones, Agua Caliente County Park, California, Rebekah Erin Wood May 2014

Fault And Fluid Interactions In The Elsinore Fault-West Salton Detachment Fault Damage Zones, Agua Caliente County Park, California, Rebekah Erin Wood

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This study area provides a unique opportunity to study the intersection of the Elsinore and West Salton detachment faults in southern California, effusing warm springs, and alteration products in the midst of the fault intersection. Structural mapping and compiling previous maps supply an interpretation of the fault zone geometries within the Tierra Blanca Mountains. Geochemical analysis of the crystalline basement and altered protolith help determine the effects of faulting and fluid flow in the study area. In the Tierra Blanca Mountains, the Elsinore strike-slip fault system transitions from the double-stranded Julian segment and Earthquake Valley fault in the northwest, to …


Decision Making Using Trust And Risk In Self-Adaptive Agent Organization, Kamilia Ahmadi May 2014

Decision Making Using Trust And Risk In Self-Adaptive Agent Organization, Kamilia Ahmadi

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Interaction between agents is one of the key factors in multi-agent societies in order to cooperatively execute complex tasks which are beyond the capability of a single agent. In the self-adaptation society, agents try to keep best neighbors around themselves. Agents use history of past iterations to evaluate their neighbors and locally modify their structural links. Main characteristics of this model are its decentralization, dynamicity and no need of external control. This research at first deals with implementing self-adaptive agent organization. Then it focuses on evaluating cooperation peers in decision making. Trust as an evaluation mechanism lies at the core …


Physically Based Preconditioning Techniques Applied To The First Order Particle Transport And To Fluid Transport In Porous Media, Michael Rigley May 2014

Physically Based Preconditioning Techniques Applied To The First Order Particle Transport And To Fluid Transport In Porous Media, Michael Rigley

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Solving linear systems is at the heart of many scientific applications from the PreAlgebra's student solving for x and y for basic geometry problems to the computational scientist solving billions of equations with billions of variables for weather forecasting, modeling fusion reactions, or web search algorithms. In this study we look at improving the efficiency of solving large linear systems that result from two applications. The first includes linear systems that result from solving differential equations for the movement of atomic particles in particle emitting, void, and absorbing regions. The second includes solving linear systems that result from solving differential …


Conformal Gravity And Time, Jeffrey Shafiq Hazboun May 2014

Conformal Gravity And Time, Jeffrey Shafiq Hazboun

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Within the last year, two acclaimed physics experiments have probed further into the extremes of our physical understanding. The Large Hadron Collider, the largest experiment ever constructed, has detected a Higgs boson, which establishes a mass scale for the fundamental particles. The Planck mission satellite has made the most accurate measurements of the cosmic microwave background radiation, which is the oldest data about the early universe we are currently able to measure directly. The mission corroborated the proportions of dark matter and dark energy are all very close to expected values. While these experiments have helped solidify the current working …


Climate Forcings On Groundwater Variations In Utah And The Great Basin, Kirsti A. Hakala May 2014

Climate Forcings On Groundwater Variations In Utah And The Great Basin, Kirsti A. Hakala

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Groundwater levels over northern Utah have undergone a declining trend since the 1960’s. This trend has made apparent the need to understand the relationship between climate and groundwater resources. Such necessary information is already in dire need in places such as California. At the close of 2013, California had experienced its driest year in recorded history, with severe drought continuing for the foreseeable future. Utah is the second driest state in the U.S., and therefore has been paying close attention to California’s current water crises. Water resource projections may prove to be one of the most vital pieces of information …


Bay Of Bengal: Coupling Of Pre-Monsoon Tropical Cyclones With The Monsoon Onset In Myanmar, Boniface Opoku Fosu May 2014

Bay Of Bengal: Coupling Of Pre-Monsoon Tropical Cyclones With The Monsoon Onset In Myanmar, Boniface Opoku Fosu

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Myanmar remained largely closed to the world through political instability for several years, when it continued to suffer terribly at the hands of nature that remained largely unknown. Of note is the period between 2008 and 2013, during which the country suffered at least eight major natural calamities that killed more than 141,000 people and affected 3.2 million. The worst of these was Cyclone Nargis in May 2008 that killed more than 130,000. With an estimated $4 billion in damages, Nargis remains the deadliest and most destructive named cyclone ever to have occurred in the North Indian Ocean. Recent studies …


Minimizing Aggregate Movements For Interval Coverage, Aaron M. Andrews May 2014

Minimizing Aggregate Movements For Interval Coverage, Aaron M. Andrews

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

We present an efficient algorithm for solving an interval coverage problem. Given n intervals of the same length on a line L and a line segment B on L, we want to move the intervals along L such that every point of B is covered by at least one interval and the sum of the moving distances of all intervals is minimized. As a fundamental computational geometry problem, it has applications in mobile sensor barrier coverage in wireless sensor networks. The previous work gave an O(n2) time algorithm for it. In this thesis, by discovering …


Online Media Use And Adoption By Hurricane Sandy Affected Fire And Police Departments, Apoorva Chauhan May 2014

Online Media Use And Adoption By Hurricane Sandy Affected Fire And Police Departments, Apoorva Chauhan

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In this thesis work, I examine the use and adoption of online communication media by 840 fire and police departments that were affected by the 2012 Hurricane Sandy. I began by exploring how and why these fire and police departments used (or did not use) online media to communicate with the public during Hurricane Sandy. Results show that fire and police departments used online media during Hurricane Sandy to give timely and relevant information to the public about things such as evacuations, damages, weather, and cleanup and to engage in two-way communications with their constituents. In their messages, fire and …


Are Experimentally Derived Estimates Of Thermal Tolerance Useful In Interpreting Species Distribution Models, Iva Sokolovska May 2014

Are Experimentally Derived Estimates Of Thermal Tolerance Useful In Interpreting Species Distribution Models, Iva Sokolovska

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Species distribution models are frequently used in ecology to predict the spatial and temporal occurrence of organisms. Direct interpretation of these models assumes that the relationships between the organisms and their environment are manifestations of causal mechanisms. However, in general, the mechanisms producing these associations have not been experimentally validated, which questions our confidence in their interpretation and application. Temperature is one of the most important factors influencing the fitness and distribution of aquatic organisms, and studying the thermal physiology of aquatic invertebrates could provide a useful approach for validating predictions of the species distribution models.

Experimental thermal tolerance studies, …


On The Complexity Of Collecting Items With A Maximal Sliding Agent, Pedro J. Tejada May 2014

On The Complexity Of Collecting Items With A Maximal Sliding Agent, Pedro J. Tejada

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

We study the computational complexity of collecting items inside a grid map with obstacles, using an agent that always slides to the maximal extend, until it is stopped by an obstacle. An agent could be, for example, a robot or a vehicle, while obstacles could be walls or other immovable objects, and items could be packages that need to be picked up.

This problem has very natural applications in robotics. The restricted type of motion of the agent naturally models movement on a frictionless surface, and movement of a robot with limited sensing capabilities and thus limited localization. For example, …


In Situ Stress And Geology From The Mh-2 Borehole, Mountain Home, Idaho: Implications For Geothermal Exploration From Fractures, Rock Properties, And Geomechanics, James Andrew Kessler May 2014

In Situ Stress And Geology From The Mh-2 Borehole, Mountain Home, Idaho: Implications For Geothermal Exploration From Fractures, Rock Properties, And Geomechanics, James Andrew Kessler

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Geothermal energy is being explored as a supplement to traditional fossil fuel resources to meet growing energy demand and reduce carbon emissions. Geothermal energy plants harvest heat stored in the Earth’s subsurface by bringing high temperature fluids to the surface and generating steam to produce electricity. Development of geothermal resources is often inhibited by large upfront risk and expense. Successful mitigation of those costs and risks begins with efficient characterization of the resource before development. A typically successful geothermal reservoir consists of a fractured reservoir that conducts hydrothermal fluids and a cap rock seal to limit convective heat loss through …


Family-Wise Error Rate Control In Quantitative Trait Loci (Qtl) Mapping And Gene Ontology Graphs With Remarks On Family Selection, Garrett Saunders May 2014

Family-Wise Error Rate Control In Quantitative Trait Loci (Qtl) Mapping And Gene Ontology Graphs With Remarks On Family Selection, Garrett Saunders

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

One of the great aims of statistics, the science of collecting, analyzing, and interpreting data, is to protect against the probability of falsely rejecting an accepted claim, or hypothesis, given observed data stemming from some experiment. This is generally known as protecting against a Type I Error, or controlling the Type I Error rate. The extension of this protection against Type I Errors to the situation where thousands upon thousands of hypothesis are examined simultaneously is known as multiple hypothesis testing. This dissertation presents an improvement to an existing multiple hypothesis testing approach, the Focus Level method, specific to gene …


Implementation And Application Of The Curds And Whey Algorithm To Regression Problems, John Kidd May 2014

Implementation And Application Of The Curds And Whey Algorithm To Regression Problems, John Kidd

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A common statistical problem is trying to predict two or more variables using a set of predictor variables. The simplest model for this situation is called multivariate linear regression. This method uses each set of predictor variables to predict each of the response variables separately. This approach seems counter-intuitive as any possible relationship between the variables being predicted is ignored.

Breiman and Friedman found a way to take advantage of relationships among the response variables to increase the accuracy of the predictions for each of the predicted variables with an algorithm they called Curds and
Whey. It uses other statistical …


Computational Modeling Of Doped Helium Clusters, Ryan Carlsen May 2014

Computational Modeling Of Doped Helium Clusters, Ryan Carlsen

Physics Capstone Projects

Prior to starting my coursework for this class, I had little experience in this area. I had done some related coursework in physical chemistry and computer science, but I had little direct experience. Thus, over the course of the year I learned very many things that are important to the research, but I did not reach a stage at which a lot of output occurred. Thus, in general this is a report of the things that I learned that will enable me to be effective in generating research output in the future, as I plan to continue participating int his …


Soft Circuits: Improving Attitudes Toward Circuits Through Crafternoons, Darren Mckinnon May 2014

Soft Circuits: Improving Attitudes Toward Circuits Through Crafternoons, Darren Mckinnon

Physics Capstone Projects

Historically, STEM fields (science, technology, engineering, and mathematics) have shown to be less appealing to girls and women. In an attempt to appeal directly to females learning the science of circuits, Utah State University added a new soft circuits lab involving sewing circuits using conductive thread. Building upon the work of the Georgia Tech computing camps, attitude changes due to this soft circuits lab were studied. A Utah State University physics course for elementary education majors comprised the test group. The test group was largely comprised of females, who as a whole showed a significant positive response to building circuits …


Constructing A Flat Field For Scientific Astronomical Imaging, Catharine Bunn May 2014

Constructing A Flat Field For Scientific Astronomical Imaging, Catharine Bunn

Physics Capstone Projects

There are consistent problems that occur during the process of capturing astronomical images which cause defects to be present on the raw image captured. Some of these problems include vignetting, dust on the lens or the digital sensor’s surface, and dead or less sensitive pixels. This is a problem when the images are meant to be used in photometry, where the brightness of each pixel is taken into account. One can simply clean all surfaces of dust, but it will always come back. A more solid solution is to use a calibration frame called a “flat field” to correct each …


High Precision Rapid Convergence Of Asian Options, Mario Y. Harper May 2014

High Precision Rapid Convergence Of Asian Options, Mario Y. Harper

Physics Capstone Projects

We show various methods that increase the precision and convergence speed of simulated stochastic processes. We demonstrate our precision and speed by using an example from the finance world, namely that of an Asian Option. An Asian Option is a path dependent pricing mechanism that is normally priced using Monte Carlo methods, it can be thought of as a path dependent diffusion equation. We show that the precision of the simulations is increased by 70% using Control Variates (derived by approximating the true mean from an analytic closed form solution). Using sequential Monte Carlo and parallel computing across a GPU …


Hot Faults:Iridescent Slip Surfaces With Metallic Luster Document High-Temperature Ancientseismicity In The Wasatch Fault Zone, Ut, Usa, James P. Evans, Mitchell R. Prante, Susanne U. Janecke, Alexis K. Ault, Dennis L. Newell May 2014

Hot Faults:Iridescent Slip Surfaces With Metallic Luster Document High-Temperature Ancientseismicity In The Wasatch Fault Zone, Ut, Usa, James P. Evans, Mitchell R. Prante, Susanne U. Janecke, Alexis K. Ault, Dennis L. Newell

Geosciences Faculty Publications

We document new geological indicators of ancient seismicity in the form of highly reflective, iridescent, hematite-coated fault surfaces. Small faults that cut the Paleoproterozoic Farmington Canyon Complex in the footwall damage zone of the Brigham City segment of the Wasatch fault (Utah, USA) are smooth to striated surfaces, tens of square centimeters to 30 m2 in area. The dull-rusty to high-metallic luster and moderate- to high-gloss surfaces exhibit multicolored elliptical iridescent patches ∼0.5–3 cm across. Preexisting hematite crystals were deformed during slip on 1–200-mm-thick slip surfaces. Textural observations, X-ray diffraction, X-ray photoelectron spectroscopy, electron backscattered diffraction analysis, surface metrology, and …


Family-Wise Error Rate Control In Quantitative Trait Loci (Qtl) Mapping And Gene Ontology Graphs With Remarks On Family Selection, Garrett Saunders May 2014

Family-Wise Error Rate Control In Quantitative Trait Loci (Qtl) Mapping And Gene Ontology Graphs With Remarks On Family Selection, Garrett Saunders

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

One of the great aims of statistics, the science of collecting, analyzing, and interpreting data, is to protect against the probability of falsely rejecting an accepted claim, or hypothesis, given observed data stemming from some experiment. This is generally known as protecting against a Type I Error, or controlling the Type I Error rate. The extension of this protection against Type I Errors to the situation where thousands upon thousands of hypotheses are examined simultaneously is known as multiple hypothesis testing. This dissertation presents an improvement to an existing multiple hypothesis testing approach, the Focus Level method, specific to gene …


Gravitational Wave Astrophysics With Compact Binary Systems, Eric Addison May 2014

Gravitational Wave Astrophysics With Compact Binary Systems, Eric Addison

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Gravitational waves are ripples in the fabric of spacetime that convey information about changing gravitational fields. Large-scale detection projects are currently in operation, and more advanced detectors are being designed and built. Though we have yet to make a direct detection of a gravitational wave signal, upgrades to current detectors are expected to bring the first detections within the next year or two.

Gravitational waves will bring us information about astrophysical phenomena that is complementary to the information gained from photon-based observations (e.g., telescopes and radio receivers). One of the primary sources of gravitational waves are binary systems: two massive …


Molecular Systematics, Historical Biogeography, And Evolution Of Spider Wasps (Hymenoptera: Pompilidae), Juanita Rodriguez May 2014

Molecular Systematics, Historical Biogeography, And Evolution Of Spider Wasps (Hymenoptera: Pompilidae), Juanita Rodriguez

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The study of the diversity and classification of any group of organisms provides a foundation for further scientific studies in ecology, evolution, and conservation. Insects are among the most diverse organisms that inhabit the planet, but knowledge of their diversity and classification is still limited. One understudied group of insects is spider wasps. These are solitary parasitoids that use one spider to lay a single egg. There are approximately 5,000 described species, and many more to be described. Unfortunately, fewer than 10 scientists worldwide study these insects. One reason the group has not been very well studied is the difficulty …


Mesoscale Deformational Features Near Outcrop Analogs Of A Reservoir-Seal Interface: Implications For Seal Failure, Santiago L. Flores May 2014

Mesoscale Deformational Features Near Outcrop Analogs Of A Reservoir-Seal Interface: Implications For Seal Failure, Santiago L. Flores

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The boundary that separates reservoir rocks from caprock seals is generally considered a flow barrier for reservoir fluids. Buoyant fluids do no flow through the caprocks because they have low permeability and molecular forces at the base of the caprock resist upward flow. Deformation at the reservoir/caprock boundary may include fractures that increase permeability and lessen the effect of the molecular forces.

The injection and storage of carbon dioxide (CO2) in porous sandstone with effective top seals below earth’s surface is a possible solution for reducing the amount of human-created CO2 in the atmosphere. Uplift and erosion …


Structure And Multi-Center Bonding: From Atomic Clusters To Solid Phase Materials, Timur R. Galeev May 2014

Structure And Multi-Center Bonding: From Atomic Clusters To Solid Phase Materials, Timur R. Galeev

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The work presented in this dissertation has been focused on structure, stability, and chemical bonding of atomic clusters and solid-state compounds. The common thread was development of theoretical models and methods capable of interpreting bonding and hence, structures of these species. A major part of this work presents joint experimental and theoretical studies of a large series of doped boron clusters. The dissertation introduces a new theoretical tool for interpretation of bonding of solid phase materials in chemically intuitive terms of localized and multi-center bonds. Understanding how interactions between atoms in sub-nano clusters and solid-state compounds determine their structures, physical …


Statistical Modeling, Exploration, And Visualization Of Snow Water Equivalent Data, James Beguah Odei May 2014

Statistical Modeling, Exploration, And Visualization Of Snow Water Equivalent Data, James Beguah Odei

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Due to a continual increase in the demand for water as well as an ongoing regional drought, there is an imminent need to monitor and forecast water resources in the Western United States. In particular, water resources in the Intermountain West rely heavily on snow water storage. Thus, the need to improve seasonal forecasts of snowpack and considering new techniques would allow water resources to be more effectively managed throughout the entire water-year. Many available models used in forecasting snow water equivalent (SWE) measurements require delicate calibrations.

In contrast to the physical SWE models most commonly used for forecasting, we …


Modeling The Defect Density Of States Of Disordered Sio2 Through Cathodoluminescence, Amberly Evans Jensen May 2014

Modeling The Defect Density Of States Of Disordered Sio2 Through Cathodoluminescence, Amberly Evans Jensen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Spacecraft charging is the accumulation of an electrical charge on orbiting spacecraft induced by the space plasma environment and has harmful effects on the electrical functionality of a spacecraft. This is studied extensively, particularly in the Materials Physics Group (MPG) at Utah State University (USU). During charging studies performed by the MPG, another potentially problematic effect of the space plasma environment on spacecraft was observed: light emanating from the sample undergoing electron beam bombardment. Space-based observatories are one type of spacecraft on which this luminescence may occur. If the luminescence from the material caused by the space plasma is within …