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Full-Text Articles in Physical Sciences and Mathematics

Nanomaterials Used To Destroy Water Contaminants, Roger Harrison Mar 2016

Nanomaterials Used To Destroy Water Contaminants, Roger Harrison

Journal of Undergraduate Research

1. Evaluation of how well the academic objectives of the proposal were met

Students working in the mentoring environment synthesized nanomaterials composed of ZnO and characterized the materials by SEM, TEM, XRD, and IR. They then used the materials as efficient photocatalysts to destroy dyes. They applied reactions and knowledge they had learned in their chemistry courses. They learned to solve problems by finding new ways to synthesize or characterize their compounds. They learned to run, fix, and change settings on multifaceted instruments. They learned to trouble-shoot problems to solve instrumental errors. They learned to reduce human error and understand …


Trace Element Inputs From Natural And Anthropogenic Sources In An Agricultural Watershed, Middle Provo River, Utah, Timothy Holman Goodsell Mar 2016

Trace Element Inputs From Natural And Anthropogenic Sources In An Agricultural Watershed, Middle Provo River, Utah, Timothy Holman Goodsell

Theses and Dissertations

Water chemistry in rivers is impacted by a variety of natural and anthropogenic processes including agricultural runoff, urban runoff, storm runoff, groundwater inputs, and the built environment. In this study we used trace element concentrations (including As, B, Ce, Co, Cu, Li, Mn, Rb, Sb, Sr, Tl, V, and Zn) and continuous measurements of flow rates and specific conductance to investigate dynamic processes affecting water quality in a rapidly urbanizing agricultural area typical of the western U.S. The middle Provo River, located in northern Utah, USA, was selected as the study area because it is well instrumented with water quality …


Novel Sputtered Stationary Phases For Solid Phase Microextraction, And Other Coatings And Materials For Surface Applications, Anubhav Diwan Mar 2016

Novel Sputtered Stationary Phases For Solid Phase Microextraction, And Other Coatings And Materials For Surface Applications, Anubhav Diwan

Theses and Dissertations

The primary focus of my work has been to prepare new solid adsorbents for solid phase microextraction (SPME) via sputtering of silicon. The orientation of the silica substrates/fibers and the sputtering pressure induced the formation of porous and columnar structures. Sputtering was performed for different times to yield fibers with different thicknesses. Piranha treatment of the surface increased the concentration of silanol groups, which underwent condensation with vapor deposited octadecyldimethylmonomethoxy silane to incorporate octadecyl chains onto the fiber surfaces. Silanized, sputtered fibers were preconditioned for 3 h at 320 °C to remove the unreacted chains. Comparison of the extraction efficiencies …


Modeling Individual Health Care Utilization, Matthew Aaron Webb Mar 2016

Modeling Individual Health Care Utilization, Matthew Aaron Webb

Theses and Dissertations

Health care represents an increasing proportion of global consumption. We discuss ways to model health care utilization on an individual basis. We present a probabilistic, generative model of utilization. Leveraging previously observed utilization levels, we learn a latent structure that can be used to accurately understand risk and make predictions. We evaluate the effectiveness of the model using data from a large population.


Enabling Optimizations Through Demodularization, Blake Dennis Johnson Mar 2016

Enabling Optimizations Through Demodularization, Blake Dennis Johnson

Theses and Dissertations

Programmers want to write modular programs to increase maintainability and create abstractions, but modularity hampers optimizations, especially when modules are compiled separately or written in different languages. In languages with syntactic extension capabilities, each module in a program can be written in a separate language, and the module system must ensure that the modules interoperate correctly. In Racket, the module system ensures this by separating module code into phases for runtime and compile-time and allowing phased imports and exports inside modules. We present an algorithm, called demodularization, that combines all executable code from a phased modular program into a single …


14-3-3Ζ Regulation Of Metastasis Through Mediation Of Liprin-Α And Liprin-Β, Rachel Hynes Mar 2016

14-3-3Ζ Regulation Of Metastasis Through Mediation Of Liprin-Α And Liprin-Β, Rachel Hynes

Theses and Dissertations

Cancer is a set of varied and diverse diseases that share common characteristics, such as active proliferation, increased replicative potential, and tissue invasion or metastasis. One protein, 14-3-3ζ, is shown to be upregulated in a number of different cancers and also correlates with poor patient prognosis, recurrence, and mortality. This protein comes from a family of adapter proteins known for their scaffolding ability, pro- and anti-oncogenic capabilities, and affinity for phosphorylated substrates. It has been shown previously to participate in cancer progression, subversion of apoptosis, and to increase chemoresistance. Herein we will discuss the ability of 14-3-3ζ to promote distant-site …


Development And Application Of New Solid-State Models For Low-Energy Vibrations, Lattice Defects, Entropies Of Mixing, And Magnetic Properties, Jacob M. Schliesser Mar 2016

Development And Application Of New Solid-State Models For Low-Energy Vibrations, Lattice Defects, Entropies Of Mixing, And Magnetic Properties, Jacob M. Schliesser

Theses and Dissertations

Low-temperature heat capacity data contain information on the physical properties of materials, and new models continue to be developed to aid in the analysis and interpretation of heat capacity data into physically meaningful properties. This work presents the development of two such models and their application to real material systems. Equations describing low-energy vibrational modes with a gap in the density of states (DOS) have been derived and tested on several material systems with known gaps in the DOS, and the origins of such gaps in the DOS are presented. Lattice vacancies have been shown to produce a two-level system …


Construction And Isomorphism Of Landau-Ginzburg B-Model Frobenius Algebras, Matthew Robert Brown Mar 2016

Construction And Isomorphism Of Landau-Ginzburg B-Model Frobenius Algebras, Matthew Robert Brown

Theses and Dissertations

Landau-Ginzburg Mirror Symmetry provides for the construction of two algebraic objects, called the A- and B-models. Special cases of these models–constructed using invertible polynomials and abelian symmetry groups–are well understood. In this thesis, we consider generalizations of the B-model, and specifically address the associativity of the multiplication in these models. We also prove an explicit B-model isomorphism for a class of polynomials in three variables.


The Principles Of Effective Teaching Student Teachershave The Opportunity To Learn In An Alternativestudent Teaching Structure, Danielle Rose Divis Mar 2016

The Principles Of Effective Teaching Student Teachershave The Opportunity To Learn In An Alternativestudent Teaching Structure, Danielle Rose Divis

Theses and Dissertations

Research has shown that the focus of mathematics student teaching programs is typically classroom management and non-mathematics specific teaching strategies. However, the redesigned BYU student teaching structure has proven to help facilitate a greater focus on mathematics-specific pedagogy and student mathematics during post-lesson reflection meeting conversations. This study analyzed what specific principles of NCTM’s standards of effective teaching were discussed in the reflection meetings of this redesigned structure. This study found that the student teachers extensively discussed seven of the eight principles NCTM considers to be necessary for effective mathematics teaching. Other pedagogical principles pertaining to student mathematical learning not …


Development, Evaluation, And Validation Of A High-Resolution Directivity Measurement System For Played Musical Instruments, K Joshua Bodon Mar 2016

Development, Evaluation, And Validation Of A High-Resolution Directivity Measurement System For Played Musical Instruments, K Joshua Bodon

Theses and Dissertations

A high-resolution directivity measurement system at Brigham Young University has been renovated and upgraded. Acoustical treatments have been installed on the microphone array, professional-grade audio hardware and cabling have been utilized, and user-friendly MATLAB processing and plotting codes have been developed. The directivities of 16 played musical instruments and several loudspeakers have been measured by the system, processed, and plotted. Using loudspeakers as simulated musicians, a comprehensive analysis was completed to validate the system and understand its error bounds. A comparison and evaluation of repeated-capture to single-capture spherical systems was made to demonstrate the high level of detail provided by …


Improvements To The Two-Point In Situ Method For Measurement Of The Room Constant And Sound Power In Semi-Reverberant Rooms, Zachary R. Jensen Mar 2016

Improvements To The Two-Point In Situ Method For Measurement Of The Room Constant And Sound Power In Semi-Reverberant Rooms, Zachary R. Jensen

Theses and Dissertations

The two-point in situ method is a technique for measuring the room constant of a semi-reverberant room and the sound power of a source in that room simultaneously using two measurement positions. Using a reference directivity source, where the directivity factor along any given axis of the source has been measured, one is able to use the Hopkins-Stryker equation to measure both the room constant and the sound power level of another source rather simply. Using both numerical and experimental data, it was found that by using generalized energy density (GED) as a measurement quantity, the results were more accurate …


Increment - Interactive Cluster Refinement, Logan Adam Mitchell Mar 2016

Increment - Interactive Cluster Refinement, Logan Adam Mitchell

Theses and Dissertations

We present INCREMENT, a cluster refinement algorithm which utilizes user feedback to refine clusterings. INCREMENT is capable of improving clusterings produced by arbitrary clustering algorithms. The initial clustering provided is first sub-clustered to improve query efficiency. A small set of select instances from each of these sub-clusters are presented to a user for labelling. Utilizing the user feedback, INCREMENT trains a feature embedder to map the input features to a new feature space. This space is learned such that spatial distance is inversely correlated with semantic similarity, determined from the user feedback. A final clustering is then formed in the …


Discovery Of Low-Molecular Weight Novel Serum Biomarkers For Diagnosing Preeclampsia And Alzheimer's Disease, Swati Anand Mar 2016

Discovery Of Low-Molecular Weight Novel Serum Biomarkers For Diagnosing Preeclampsia And Alzheimer's Disease, Swati Anand

Theses and Dissertations

Preeclampsia (PE), a life threatening pregnancy-related disorder, is characterized mainly by new onset of hypertension and proteinuria after 20 weeks of gestation. Currently, PE cannot be predicted prior to onset of symptoms and there is no cure for the disease. There is a clear value in having biomarkers able, early in a pregnancy, to identify women at risk for PE so that proper treatment therapies could be developed. Although a number of serum candidate markers have been proposed to be altered in PE patients, their use is limited due to poor sensitivity and specificity. Therefore, there is ongoing need for …


Lineations And Structural Mapping Of Io's Paterae And Mountains: Implications For Internal Stresses, Alexandra Anne Ahern Mar 2016

Lineations And Structural Mapping Of Io's Paterae And Mountains: Implications For Internal Stresses, Alexandra Anne Ahern

Theses and Dissertations

Io, the most volcanically active body in the solar system, also has some of the tallest and steepest mountains. The mountains seem to be tectonic in origin, yet the methods of their formation have not been decisively constrained and their associations with volcanic paterae are yet unclear. We have compiled global spatial statistics on mountain dimensions and orientations, lineations attributed to structures, straight patera margins, and patera dimensions in order to better define their genetic relationships and the mechanisms forming each type of feature. Additionally, we have produced 4 regional structural maps of mountain complexes and have proposed tectonic histories. …


Changing The World Of Research As We Know It, Aaron Sainsbury, Thomas Meservy Feb 2016

Changing The World Of Research As We Know It, Aaron Sainsbury, Thomas Meservy

Journal of Undergraduate Research

Research plays a vital role in the advancement of knowledge. In conjunction, feedback through idea exchange, peer reviews, and formal reviews play a vital role in every research project. With the current academic organizations in place, the impact of feedback is not fully realized because of the structure of how and when feedback is received. While collaborative communication among researchers is increasingly more reliant upon technology, there is little focus on the development and implementation of a technologybased collaboration scheme to support and sustain scientific idea exchanges among researchers.


Resolving “Mixed” Privacy Signals Untangling The Anchoring And Adjustment In The Presence Of Multiple Signals, Thong Pham, Mark Keith Feb 2016

Resolving “Mixed” Privacy Signals Untangling The Anchoring And Adjustment In The Presence Of Multiple Signals, Thong Pham, Mark Keith

Journal of Undergraduate Research

As the technologies enabling mobile and ubiquitous information rapidly evolve, so do the information privacy risks to consumers (Belanger and Crossler 2011; Pavlou 2011; Smith et al. 2011). Perceived privacy risk has been demonstrated to be a critical factor in both information disclosure intentions (Dinev and Hart 2006; Lowry et al. 2011; Xu et al. 2010) and behaviors (Keith et al. 2013; Lowry et al. 2011; Posey et al. 2010).


Epigenetic Cost Matrix, Spring Cullen, Dr. Mark Clement Feb 2016

Epigenetic Cost Matrix, Spring Cullen, Dr. Mark Clement

Journal of Undergraduate Research

Epigenetics is of vital importance, comparable to genetics, in predicting the outcome of illnesses. Bisulfite sequencing (BS) provides short DNA fragments that must be mapped in order to discover epigenetic markers. The purpose of this project is to find an optimal cost matrix to map sequences from BS DNA to a reference genome to determine patterns of methylation. A more efficient BS cost matrix will contribute to the ongoing effort to understand the epigenome and analyze data collected.


Petrologic Comparison Of The Beaver Dam And Mineral Mountains Metamorphic Complexes, Scott Zylstra, Jake Voorhees, Dr. Ron Harris Feb 2016

Petrologic Comparison Of The Beaver Dam And Mineral Mountains Metamorphic Complexes, Scott Zylstra, Jake Voorhees, Dr. Ron Harris

Journal of Undergraduate Research

Utah’s rocks, though incredibly complete in later eons, hold very little information about what was occurring in that area before 700 million years ago. In Southern Utah, only two relatively small exposures of these ancient Precambrian exist, in the west of the Beaver Dam Mountains west of St. George and the west of the Mineral Mountains west of Beaver. Therefore, it is vitally important to study these exposures, as they constitute the only clues to what was happening in Utah 1.7 billion years ago.


Exploring The Weak Mach Reflection Regime, Kevin Leete, Dr. Kent Gee Feb 2016

Exploring The Weak Mach Reflection Regime, Kevin Leete, Dr. Kent Gee

Journal of Undergraduate Research

When a shock wave reflects off a rigid surface with certain combinations of incident shock strength and angle, a Mach reflection can occur. This is when portions of the incident and reflected waves merge to create a stronger shock called a Mach stem that travels parallel to the reflecting surface. This phenomenon has been studied extensively for two extreme cases: large outdoor explosions and small, laboratory experiments of weak shocks. The purpose of this project was to design and execute an outdoor experiment where this phenomenon could be observed by microphones as well as high speed video imaging to detect …


Real-Time Webpage Adaptation For Improved User Accessibility, Parker Williams, Jeff Jenkins Feb 2016

Real-Time Webpage Adaptation For Improved User Accessibility, Parker Williams, Jeff Jenkins

Journal of Undergraduate Research

Hand tremors are experienced by millions of individuals on a daily basis, the main cause being neurological disorders and neurodegenerative diseases. Essential Tremor, “a progressive neurologic condition that causes involuntary rhythmic trembling of the hands,” affects 10 million Americans of all ages1. It is estimated that 87% of individuals ages 18-29, 86% of individuals ages 30-49, 76% of individuals ages 50-64, and 70% of individuals ages 65 and older go online daily2. With an increasing number of individuals who have access to and use of the internet, creating a real-time adaptable webpage environment for those with …


Optically Detected Magnetic Resonance Of Silicon Vacancies In Sic: Predicting Resonance Of Cylindrical Cavities, Kyle Miller, John Colton Feb 2016

Optically Detected Magnetic Resonance Of Silicon Vacancies In Sic: Predicting Resonance Of Cylindrical Cavities, Kyle Miller, John Colton

Journal of Undergraduate Research

Optically Detected Magnetic Resonance is one method of performing Electron Spin Resonance (ESR) on a material. ESR is used to determine the electron spin lifetime of a material, an important parameter for use in quantum computing. Resonant cavities are conducting containers that are frequently used in ESR to create a strong magnetic field near the sample. As such it is valuable to design a resonant cavity and predict its resonant frequency. Cylindrical cavities modified with dielectric resonators (DRs) are viable for such experiments.


Packet Inspection And Modification For Mobile Devices: Trustbase, Scott Heidbrink, Daniel Zappala Feb 2016

Packet Inspection And Modification For Mobile Devices: Trustbase, Scott Heidbrink, Daniel Zappala

Journal of Undergraduate Research

While there is a long tradition of providing protection against attackers for desktop and laptop devices, there has been less work in the mobile space. A common tool used by antivirus software is to inspect all packets entering or leaving a computer, to check for viruses or other malware. There are currently no generalpurpose tools for Android devices that provide for packet inspection and modification. There are a few tools that allow for packet capturing on mobile devices, but they can only function on “rooted” devices and do not allow modification. Since most users do not “root” their devices, these …


High Resolution Shock Capturing On Gpus, Forrest Glines, David Neilsen Feb 2016

High Resolution Shock Capturing On Gpus, Forrest Glines, David Neilsen

Journal of Undergraduate Research

This research project concerns the development simulation code to confirm neutron star mergers as the progenitors of Short Hard Gamma Ray Bursts. Short Hard Gamma Ray Bursts (SHGBs) are short (less than 2 second) high energy bursts that we observe with satellites. Their exact cause has not yet been confirmed, but they are believed to be created by the merging of either two neutron stars or a neutron star falling into a black hole. Neutron stars are ultra dense, highly magnetic, and compact stars at the end of their evolution. In a binary system the stars lose angular momentum to …


Messageguard: A Secure Webmail System Coupling Security With Usability, Joshua Lowe, Kent Seamons Feb 2016

Messageguard: A Secure Webmail System Coupling Security With Usability, Joshua Lowe, Kent Seamons

Journal of Undergraduate Research

While working on my undergraduate degree, I developed an interest for computer security and started working in the Internet Security Research Lab on campus. A PhD student who I had worked with before previously, had proposed a webmail system called MessageGuard as an ubiquitous web encryption extension. The idea behind the system is to be fully open sourced, very easy to use, and extremely secure. Not only was I able to help work on several aspects of this project with PHD, Master’s, and undergraduate students alike, but I was able to put in practice what I was learning in my …


Spectral Graph Theory For Weighted Digraphs, Alexander Zaitzeff, Jeffrey Humpherys Feb 2016

Spectral Graph Theory For Weighted Digraphs, Alexander Zaitzeff, Jeffrey Humpherys

Journal of Undergraduate Research

For digraphs weighted and unweighted, one important application is ranking: Given a directed graph, whether it be the Internet or a social network, which node (representing a web page or a person) is the most important? There are many different methods to find answer this question. A few are highest indegree, closeness centrality1, betweeness centrality2, eigenvector centrality, Katz Centrality3, and PageRank4. Our idea is to use sparsity, or the idea that in a network only has a few important nodes, to determine the ranking on a graph.


Porous Cantilevers As Chemical Sensors, Steven Noyce, Robert Davis Feb 2016

Porous Cantilevers As Chemical Sensors, Steven Noyce, Robert Davis

Journal of Undergraduate Research

Many chemical sensing methods rely on the binding mechanism of the analyte to create a measurable response, making it difficult to create new sensors quickly, but resonant sensors require only that an analyte be bound and rely on the resulting change in mass to obtain a measurement. Solid resonant microcantilevers, or small vibrating fixed-free beams, are a type of resonant sensor that have shown extremely high sensitivities in vacuum environments. The sensitivity of these cantilevers, however, decreases greatly in fluid environments such as air or water due to fluid damping. We propose that porous microcantilever sensors offers both a ten …


Trace Element Analysis Of Quartz Grains In The Wah Wah Springs Tuff And Granodiorite Intrusion, Michael Jensen, Dr. Eric Christiansen Feb 2016

Trace Element Analysis Of Quartz Grains In The Wah Wah Springs Tuff And Granodiorite Intrusion, Michael Jensen, Dr. Eric Christiansen

Journal of Undergraduate Research

The Wah Wah Springs Tuff and the Wah Wah Springs Intrusive Granodiorite are both part of the Indian Peak caldera complex in southwest Utah, an area of intense volcanic activity 30 million years ago. This time period is known for explosive silicic activity due to the subduction of the Farallon Plate along North America’s western edge. In the eruption connected with the Wah Wah Springs an estimated 5,900 km3 of magma came out of the Earth, making it one of the largest known explosive eruptions in our planet’s history. This massive eruption was partially dependent upon the changing temperatures …


Determining The Size Of A Light Source Using The Hanbury Brown And Twiss Effect, Adam Kingsley, Dallin Durfee Feb 2016

Determining The Size Of A Light Source Using The Hanbury Brown And Twiss Effect, Adam Kingsley, Dallin Durfee

Journal of Undergraduate Research

In 1956, Hanbury Brown and Twiss (HBT) published a paper1 on a method of determining the angular size of a star by comparing the intensities gathered from two detectors. They used this effect by using two photomultiplier tubes and by increasing the distance between them, saw a drop in the correlation between the currents. Because the correlations are made by the interference at the detectors but only the intensity is measured, the effect is sometimes referred to as intensity interferometry.

The idea arose to use the HBT effect to teach undergraduates various principles of light in a lab setting. …


Phase Matching In Laser Generated Harmonics, David Squires, Justin Peatross Feb 2016

Phase Matching In Laser Generated Harmonics, David Squires, Justin Peatross

Journal of Undergraduate Research

In this mentored research project, we investigated how intense laser light is scattered by samples of gas. In particular, we measured light scattered in non-phase-matched directions perpendicular to the laser beam.

According to classical phase matching, the intensity of light scattered from a sample depends on whether the sample is best approximated as a continuous medium or a collection of discrete emitters (Figure 1). In the former case, as the angle between the phase-matching direction and the radiated harmonic approaches π/2 radians, the intensity of that radiated harmonic light approaches 0. In the latter case, the light intensity reaches …


Determination Of Fine Particulate Matter Composition And Development Of The Organic Aerosol Monitor, Paul Michael Cropper Feb 2016

Determination Of Fine Particulate Matter Composition And Development Of The Organic Aerosol Monitor, Paul Michael Cropper

Theses and Dissertations

Tropospheric fine particulate matter (PM) poses serious health risks and has a significant impact on global climate change. The measurement of various aspects of PM is challenging due to its complex chemical nature. This dissertation addresses various aspects of PM, including composition, measurement, and visibility. The U.S. Environmental Protection Agency (EPA) proposed a new secondary standard based on visibility in urban areas using 24-h averaged measurements of either light scatter or PM concentration. However shorter averaging times may better represent human perception of visibility. Data from two studies conducted in Lindon, UT, 2012, and Rubidoux, CA, 2003, were used to …