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Full-Text Articles in Physical Sciences and Mathematics

The Effects Of Bison On Cattle Winter Range In The Henry Mountains Of South Central Utah: Resolving A Conflict, Ian M. Ware Dec 2012

The Effects Of Bison On Cattle Winter Range In The Henry Mountains Of South Central Utah: Resolving A Conflict, Ian M. Ware

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The American Bison in the Henry Mountains are one of the last free-roaming, genetically pure herds of bison remaining in North America. Over the last decade, the herd has used a cattle winter range during the summer and early fall, creating a conflict between the wildlife officials who manage the bison population, and Bureau of Land Management officials and local ranchers who manage the rangeland. At the heart of this conflict is the question of whether bison are negatively impacting the rangeland resource, potentially reducing the abundance of preferable plant species. Negative impacts could include reduced forage availability in the …


Synthesis And Biological Activity Of Aminoglycosides And 1,4-Naphthoquinone Derivatives, Marina Fosso Yatchang Dec 2012

Synthesis And Biological Activity Of Aminoglycosides And 1,4-Naphthoquinone Derivatives, Marina Fosso Yatchang

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The research described in this dissertation is at the interface of organic chemistry and biology, and it aimed at designing and synthesizing biologically active molecules for the possible development of therapeutic agents.

Spinal muscular atrophy is an incurable disease that affects 1 in every 6000 babies, making it the leading genetic cause of infant mortality. While no treatment is available, efforts are being taken to solve this issue. Part of the work outlined in this dissertation was carried out in collaboration with researchers from the University of Missouri to investigate a potential therapeutic for this disease.

In addition, the continuous …


Visual Data Mining Techniques For Functional Actigraphy Data: An Object-Oriented Approach In R, Abbass Sharif Dec 2012

Visual Data Mining Techniques For Functional Actigraphy Data: An Object-Oriented Approach In R, Abbass Sharif

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Actigraphy, a technology for measuring a subject's overall activity level almost continuously over time, has gained a lot of momentum over the last few years. An actigraph, a watch-like device that can be attached to the wrist or ankle of a subject, uses an accelerometer to measure human movement every minute or even every 15 seconds. Actigraphy data is often treated as functional data. In this dissertation, we discuss what has been done regarding the visualization of actigraphy data, and then we will explain the three main goals we achieved: (i) develop new multivariate visualization techniques for actigraphy data; (ii) …


The Application Of Tomographic Reconstruction Techniques To Ill-Conditioned Inverse Problems In Atmospheric Science And Biomedical Imaging, Vern Philip Hart Ii Dec 2012

The Application Of Tomographic Reconstruction Techniques To Ill-Conditioned Inverse Problems In Atmospheric Science And Biomedical Imaging, Vern Philip Hart Ii

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Tomography is an imaging technique in which 3D models of objects are created from several 2D projections viewed at different angles. When the number of available projections is limited, the resulting data are said to be sparse. This restriction is often a direct result of the imaging geometry used to acquire the data. One-sided views and a small number of receivers can reduce the range of available projections, which makes the object more difficult to reconstruct. Approximate solutions to difficult imaging problems can be obtained using a class of iterative algorithms known as the algebraic reconstruction techniques (ARTs). The presented …


Space Plug-And-Play Architecture Networking: A Self-Configuring Heterogeneous Network Architecture, Jacob Holt Christensen Dec 2012

Space Plug-And-Play Architecture Networking: A Self-Configuring Heterogeneous Network Architecture, Jacob Holt Christensen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In spacecraft engineering, the time and money involved in satellite construction is largely spent on design and integration of custom hardware and software. These efforts are duplicated for nearly every satellite with little to no reuse between spacecraft. There is a huge potential for cost savings in removing the duplication of work. However, there is a lack of standardization in the spaceflight community, causing soaring costs and delayed schedules as each component of a spacecraft is individually designed and custom built.

The Air Force Research Laboratory (AFRL) has developed the Space Plug-and-Play Architecture (SPA) to address this problem. SPA provides …


In Situ Measurements Of Electron-Beam-Induced Surface Voltage Of Highly Resistive Materials, Joshua Hodges Dec 2012

In Situ Measurements Of Electron-Beam-Induced Surface Voltage Of Highly Resistive Materials, Joshua Hodges

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Surface charging and subsequent electrostatic discharge due to interactions with the space environment is one of the primary concerns of spacecraft charging studies. Laboratory measurements of the evolution of surface voltages and dissipation currents under simulated space conditions are the primary method used to determine the response of key spacecraft materials to diverse incident fluxes. Increasing the database of information for the electronic properties of insulating materials can assist spacecraft designers in mitigating the harsh effects of the space environment.

The Utah State Materials Physics Group, with the funding of the NASA James Webb Space Telescope project and personnel support …


Modeling Lithospheric Rheology From Modern Measurements Of Bonneville Shoreline Deformation, Eric P. Beard Dec 2012

Modeling Lithospheric Rheology From Modern Measurements Of Bonneville Shoreline Deformation, Eric P. Beard

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Here I develop a new method for estimating differences in elevation between pairs of paleo-lake shoreline features. This method is applied to Lake Bonneville, a large lake that inundated nearly 1/3 of the state of Utah as well as parts of Nevada and Idaho from 34 to 11.5 thousand years ago. Under the weight of the lake water load, the surface of the Earth was depressed by up to 75 m. This occurred as Earth mantle rock at depth flowed outward in response to the weight of the lake. I use this new methodology to compile here a denser sample …


A Mechanistic Study Of Catalytic Promiscuity In Protein Phosphatase 1, Yuan Chu Aug 2012

A Mechanistic Study Of Catalytic Promiscuity In Protein Phosphatase 1, Yuan Chu

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

"Catalytic promiscuous" enzymes, which possess additional activities besides their "native" activity, albeit with a lower efficiency than the main reaction, have become a new frontier for biochemistry and have received considerable attention. Catalytic promiscuity has been suggested to contribute to enzyme evolution through the mechanism of gene duplication followed by specialization of one of the two copies for the new function. Mimicking this evolutionary shortcut could also provide a more efficient route to changing the function of proteins by directed evolution.

The promiscuous phosphatase PP1 is a member of the phosphoprotein phosphatase (PPP) gene family, which is critical for the …


The Chemical Evolution Of Oceanic And Continental Lithosphere: Case Studies In The Us Cordillera, Marlon Mauricio Jean Aug 2012

The Chemical Evolution Of Oceanic And Continental Lithosphere: Case Studies In The Us Cordillera, Marlon Mauricio Jean

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Among the terrestrial planets, only Earth has volcanism and plutonism that is related to plate tectonics. At the bottom of the oceans, mid-ocean ridges form where tectonic plates drift apart. More visible, and explosively dangerous, is volcanism related to the subduction of oceanic plates back into the Earth’s mantle. Less clear is the origin of the third major type of volcanism, the so-called intra-plate volcanism, which is thought to represent thermally driven upwellings from the lower mantle. This dissertation investigates two of these unique volcano-tectonic settings which occur in the western United States.

Subduction zones are regions of intense earthquake …


The Effect Of Growth Parameters On The Height And Density Of Carbon Nanotube Forests, Robert Welch Call Aug 2012

The Effect Of Growth Parameters On The Height And Density Of Carbon Nanotube Forests, Robert Welch Call

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Rolled-up graphene sheets, known as carbon nanotubes, are grown in vertically aligned arrays called carbon nanotube forests (CNTFs). CNTFs make extremely dark surfaces. They are being investigated for use on space crafts as calibration surfaces and to protect optical sensors from unwanted signals. These CNTFs are grown by injecting a precursor consisting of a metal catalyst particle and a hydrocarbon component into a furnace at high temperature (~700°C). This study investigates the influence of several different growth parameters on the final height and density of the CNTF. Height and density influence the absorbance of the surface at different wavelengths.


Sigtree: An Automated Meta-Analytic Approach To Find Significant Branches In A Phylogenetic Tree, Todd R. Jones Aug 2012

Sigtree: An Automated Meta-Analytic Approach To Find Significant Branches In A Phylogenetic Tree, Todd R. Jones

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

An experiment was performed on two groups of mice, the first group receiving a refined wheat diet, and the second group receiving a whole wheat diet. The levels of abundance of hundreds of bacteria in the guts of the mice were measured. Of interest was whether the levels of these bacteria were different depending on type of diet. In addition, it was desired to examine differences by diet in all of the families of bacteria. These family relationships are represented in a tree, and it was determined helpful to color the branches of this tree based on the differences of …


Sustainable Ski Resorts In The State Of Utah: Working Toward The Future, Andrew Call May 2012

Sustainable Ski Resorts In The State Of Utah: Working Toward The Future, Andrew Call

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Utah State University Extension branch funded a research project designed to meet an identified need and create a baseline in knowledge of the implementation of environmentally sustainable practices among Utah ski resorts. Because of the potential impacts of climate change and unsustainable practices that negatively impact both the biophysical and human/cultural aspects of these environments, the ski resort industry is facing an uncertain future both environmentally and economically. However, very little is known about this issue, or how to address it. Collecting baseline information on the subject of environmental sustainability amongst Utah area ski resorts is crucial to ensure …


Planning In Incomplete Domains, Jared William Robertson May 2012

Planning In Incomplete Domains, Jared William Robertson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Automated planning in computer science consists of finding a sequence of actions leading from an initial state to a goal state. People who have expert knowledge of the specific problem domain work with experts in automated planning to define the domain states and actions. This knowledge engineering required to create complete and correct domain descriptions for planning problems is often very costly and difficult. Our goal with incomplete planning is to allow people to program domains without the need for planning experts.

Throughout the process of instruction of intelligent systems, teachers can often leave out whole procedures and aspects of …


Carbon Sequestration On Utah Rangelands: A Landowner Perspective, Seth Cook May 2012

Carbon Sequestration On Utah Rangelands: A Landowner Perspective, Seth Cook

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Carbon sequestration is the removal of carbon dioxide from the air and storing it in plants and soil through natural processes. Rangelands can be managed to sequester carbon and mitigate climate change. Supported by the Utah Agricultural Experiment Station, this study assessed Utah rangeland owners’ perceptions of carbon sequestration and explored factors influencing their likelihood of participation in relevant programs. Data were collected through interviews and a statewide survey of Utah rangeland owners. Over two-thirds of respondents were aware of carbon sequestration and viewed it positively. Those who thought the climate had been changing over the past 30 years tended …


Planning, Acting, And Learning In Incomplete Domains, Christopher H. Weber May 2012

Planning, Acting, And Learning In Incomplete Domains, Christopher H. Weber

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The engineering of complete planning domain descriptions is often very costly because of human error or lack of domain knowledge. Learning complete domain descriptions is also very challenging because many features are irrelevant to achieving the goals and data may be scarce. Given incomplete knowledge of their actions, agents can ignore the incompleteness, plan around it, ask questions of a domain expert, or learn through trial and error.

Our agent Goalie learns about the preconditions and effects of its incompletely-specified actions by monitoring the environment state. In conjunction with the plan failure explanations generated by its planner DeFault, Goalie diagnoses …


Peer-To-Peer Simulation Of Massive Virtual Environments, James Dean Mathias May 2012

Peer-To-Peer Simulation Of Massive Virtual Environments, James Dean Mathias

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Massively multiplayer games make up a large and growing segment of the computer game industry. One of the best known examples of these games is World of Warcraft, developed and published by Activision Blizzard. World of Warcraft boasts a subscriber base of over eleven million active subscribers, earning an estimated $1 billion dollars in 2010.

Some of the core issues for companies that publish these games are the cost of the computers, Internet bandwidth usage, and supporting technical staff. These costs easily reach hundreds of thousands of dollars each month, and in the case of World of Warcraft, millions of …


Combinatorial-Based Prioritization For User-Session-Based Test Suites, Schuyler Manchester May 2012

Combinatorial-Based Prioritization For User-Session-Based Test Suites, Schuyler Manchester

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Software defects caused by inadequate software testing can cost billions of dollars. Further, web application defects can be costly due to the fact that most web applications handle constant user interaction. However, software testing is often under time and budget constraints. By improving the time efficiency of software testing, many of the costs associated with defects can be saved.

Current methods for web application testing can take too long to generate test suites. In addition, studies have shown that user-session-based test suites often find faults missed by other testing techniques. This project addresses this problem by utilizing existing user sessions …


A Localized Geometric-Distortion Resilient Digital Watermarking Scheme Using Two Kinds Of Complementary Feature Points, Jiyuan Wang May 2012

A Localized Geometric-Distortion Resilient Digital Watermarking Scheme Using Two Kinds Of Complementary Feature Points, Jiyuan Wang

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

More and more digital images are being distributed over the Internet to an evergrowing number of people for sharing, studying, or other purposes. However, most of those digital products are exposed without any protection, and such information can be easily transferred, copied, and tampered without authorization simply by using readily available digital multimedia editing software. Digital watermarking techniques have been developed as a tool to discriminate whether the original content of digital media is tampered or not. A digital watermark is embedded on digital images as an invisible message and is used to demonstrate the proof by the owner.

In …


Adaptive Re-Segmentation Strategies For Accurate Bright Field Cell Tracking, Nare Hayrapetyan May 2012

Adaptive Re-Segmentation Strategies For Accurate Bright Field Cell Tracking, Nare Hayrapetyan

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Cell migration is central for many fundamental biological processes and development of multi-cellular organisms. The failure of cells to migrate or migration of cells to inappropriate locations during embryo development can result in life threatening consequences such as brain malfunctions. In adults, cell migration plays an important role in wound healing and immune responses. Failure in these processes can have dramatic medical implications and can lead to vascular diseases and tumor formation. Therefore, studying cell migration is critical to helping prevent and cure diseases.


Cell migration is usually studied by observing cells photographed through a microscope at regular time intervals. …


The Mechanisms Of Hydride Exchange, Organic Combination And Displacement Reactions, Weifang Hao May 2012

The Mechanisms Of Hydride Exchange, Organic Combination And Displacement Reactions, Weifang Hao

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The primary aim of this dissertation was to seek the answer to the question: “Is the single transition-state model appropriate for the fundamental reactions in organic chemistry?” The goal was accomplished by performing enormous kinetic data collection and detailed mechanistic analysis on several typical fundamental organic chemical reactions. Three new methodologies for differentiating between a simple one-step and complex multi-step mechanism were developed and extensively confirmed during the application in the kinetic studies of all of the reaction discussed in this dissertation. The three methods consist of (1) half-life dependence of kapp, (2) sequential linear pseudo-first-order correlation, and (3) revised …


Environmental Assessment Of Streams: Linking Land Use, Instream Stressors, And Biological Indices To Infer Likely Causes Of Ecological Impairment, Jacob J. Vander Laan May 2012

Environmental Assessment Of Streams: Linking Land Use, Instream Stressors, And Biological Indices To Infer Likely Causes Of Ecological Impairment, Jacob J. Vander Laan

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

To protect and restore stream biota, managers need to be able to both detect biological degradation and infer likely causes of impairment. Managers commonly develop indices based on stream biota to assess the biological condition of streams. However, the performance of these indices dictates the ability to detect degradation, and although index performance varies widely, the sources of this variation are often unclear. In addition, bioassessments do not identify causes of impairment. My thesis research had two general goals: 1) develop indices to measure biological condition in Nevada streams and 2) quantify relationships between land uses, stressors, and biological condition …


Production Of Biodiesel From Oleaginous Organisms Using Underutilized Wastewaters, Valerie Godfrey May 2012

Production Of Biodiesel From Oleaginous Organisms Using Underutilized Wastewaters, Valerie Godfrey

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

As part of the BioEnergy Team at Utah State Univeristy, my research objectives have been centered around the common theme of innovating new methods and
technology for producing biological compounds and, by means of chemical conversion and/or extraction, isolating new forms of biodiesel available for transportation fuel.
Within the broad scope of this project, I focused on the replacement of freshwater in cultivating such biological systems with wastewaters. If accomplished and correctly
applied, such research would reduce the environmental impact of biodiesel production by reducing the demand for freshwater. It also would reduce production costs by reducing the amount of …


Java Api-Aware Code Generation Engine: A Prototype, Chandra Sekhar Vijyapurpu May 2012

Java Api-Aware Code Generation Engine: A Prototype, Chandra Sekhar Vijyapurpu

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Software reuse enhances a programmer's productivity and reduces programming errors. Improving software reuse through libraries and frameworks is a vast problem area. This thesis offers an approach to solve two sub-problems within the problem area - to identify the right library components, and to offer code snippets that use the components correctly. The Java API-Aware Code Generation Engine, or JAGE for short, is a prototype system that demonstrates the feasibility of generating semantically valid code snippets consisting of method calls to classes in the J2SDK library.

Developers often search for sample code snippets that describe how to use the …


Rationalizing Structure, Stability, And Chemical Bonding Of Pure And Doped Clusters Isolated And Solvated Multiply Charged Anions, And Solid State Materials, Alina P. Sergeeva May 2012

Rationalizing Structure, Stability, And Chemical Bonding Of Pure And Doped Clusters Isolated And Solvated Multiply Charged Anions, And Solid State Materials, Alina P. Sergeeva

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Chemistry is the study of materials and the changes that materials undergo. One can tune the properties of the known materials and design the novel materials with desired properties knowing what is responsible for the chemical reactivity, structure, and stability of those materials. The unified chemical bonding theory could address all these questions, but we do not have one available yet. The most accepted general theory of chemical bonding was proposed by Lewis in 1916, though Lewis’s theory fails to explain the bonding in materials with delocalized electron density such as sub-nano and nanoclusters, as well as aromatic organic and …


Robust Computational Tools For Multiple Testing With Genetic Association Studies, William L. Welbourn Jr. May 2012

Robust Computational Tools For Multiple Testing With Genetic Association Studies, William L. Welbourn Jr.

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The mapping of the human genome and the completion of the Human HapMap project over the past decade have significantly altered how research is conducted with respect to the genetic epidemiology of human disease. Study designs and analytic approaches have evolved rapidly from investigations involving relatively few targeted candidate genes to hypothesis-free genome-wide association studies, where thousands – and now even millions – of single molecular mutations are simultaneously analyzed to identify regions of the genome that may influence disease. As laboratory techniques continue to improve and costs decrease, the volume of genetic data will inexorably rise, and robust tools …


The Survival And Growth Of Adult Bonneville Cutthroat Trout (Oncorhynchus Clarkii Utah) In Response To Different Movement Patterns In A Tributary Of The Logan River, Utah, Jared W. Randall May 2012

The Survival And Growth Of Adult Bonneville Cutthroat Trout (Oncorhynchus Clarkii Utah) In Response To Different Movement Patterns In A Tributary Of The Logan River, Utah, Jared W. Randall

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In the past many inland trout species were believed to be sedentary, only occupying small stream segments (20 meters) during their life span. Recently it has been found that cutthroat trout do move and many populations do contain both mobile and non-mobile strategies. Most organisms move to attain greater growth rates, but movement also leads to higher detection by predators. Both mobile and non-mobile strategies have been observed in Spawn creek, a tributary of the Logan River in Northern Utah. My research evaluated the movement patterns, survival, and growth of adult Bonneville cutthroat trout Oncorhynchus clarkii Utah. My objectives …


Structural And Functional Characterization Of The Essential Rna Helicase Mtr4, Ryan N. Jackson May 2012

Structural And Functional Characterization Of The Essential Rna Helicase Mtr4, Ryan N. Jackson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

To insure the integrity of nuclear RNA, the eukaryotic cell employs surveillance systems that identify and degrade RNAs that are detrimental or unneeded. The failure of RNA surveillance systems can lead to neurodegenerative disease states and cancer. The essential RNA helicase Mtr4 is required for the degradation and processing of several nuclear RNAs. To further the understanding of RNA surveillance and processing in eukaryotes, Ryan Jackson of the Department of Chemistry and Biochemistry at Utah State University has determined the molecular structure of Mtr4 and has used this structure to interrogate Mtr4 function biochemically. The structure revealed that Mtr4 contains …


Test Case Generation Using Combinatorial Based Coverage For Rich Web Applications, Chad Maughan May 2012

Test Case Generation Using Combinatorial Based Coverage For Rich Web Applications, Chad Maughan

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Web applications are increasingly moving business and processing logic from the server to the browser. Traditional, multiple-page request/response applications are quickly being replaced by single-page applications where complex application logic is downloaded on the initial page load and data is then subsequently fetched asynchronously via the browser's native XMLHttpRequest (XHR) object.

These new generation web applications are called Rich Web Applications (RWA). Frameworks such as the Google Web Toolkit (GWT), and JavaScript model-view-controller (MVC) frameworks such as Backbone.js are facilitating this move. With this migration, testing frameworks need to follow the logic by moving analysis and test generation from the …


1. Improving The Yield Of Biodiesel From Microalgae And Other Lipids. 2. Studies Of The Wax Ester Biosynthetic Pathway And Potential Biotechnological Application, Bradley D. Wahlen May 2012

1. Improving The Yield Of Biodiesel From Microalgae And Other Lipids. 2. Studies Of The Wax Ester Biosynthetic Pathway And Potential Biotechnological Application, Bradley D. Wahlen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The production of biofuels and oleochemicals from renewable sources offers an opportunity to reduce our dependence on fossil fuels. The work contained in this dissertation has focused on developing and improving methods for the production of biodiesel from non-traditional feedstocks and understanding biosynthetic pathways that result in the production of oleochemicals and fuels.

Pure vegetable oil can account for 70-80% of the total cost of biodiesel production. Many low-cost oils contain high amounts of free fatty acids, which are unsuitable for base-catalyzed transesterification. Herein an approach is described that efficiently accomplishes the simultaneous esterification and transesterification of both free fatty …


Integrating Remote Sensing And Ecosystem Models For Terrestrial Vegetation Analysis: Phenology, Biomass, And Stand Age, Gong Zhang May 2012

Integrating Remote Sensing And Ecosystem Models For Terrestrial Vegetation Analysis: Phenology, Biomass, And Stand Age, Gong Zhang

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Terrestrial vegetation plays an important role in global carbon cycling and climate change by assimilating carbon into biomass during the growing season and releasing it due to natural or anthropogenic disturbances. Remote sensing and ecosystem models can help us extend our studies of vegetation phenology, aboveground biomass, and disturbances from field sites to regional or global scales. Nonetheless, remote sensing-derived variables may differ in fundamental and important ways from ground measurements. With the growth of remote sensing as a key tool in geoscience research, comparisons to ground data and intercomparisons among satellite products are needed. Here I conduct three separate …