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Does Marijuana Decriminalization Make The Roads More Dangerous?, Daehyeon Kim Jul 2017

Does Marijuana Decriminalization Make The Roads More Dangerous?, Daehyeon Kim

Theses and Dissertations

As the movement to decriminalize marijuana has gained more support throughout the United States, as of early 2017, 21 states have decriminalized the possession of a small amount of marijuana for personal recreational use, and more states are expected to decriminalize marijuana (GOVERNING 2017). Despite this strong move toward decriminalizing marijuana, however, the consequences of implementing such a policy are still very much unknown. One of the concerns regarding this movement to decriminalize marijuana is its potential impact on road safety (Schrader 2015; Roberts 2017; Halsey 2015). Although there are a few studies that have examined the association between marijuana …


Comparing The Awl And Avl In Textbooks From An Intensive English Program, Michelle Morgan Hernandez Jul 2017

Comparing The Awl And Avl In Textbooks From An Intensive English Program, Michelle Morgan Hernandez

Theses and Dissertations

Academic vocabulary is an important determiner of academic success for both native and non-native speakers of English (Corson, 1997; Gardner, 2013; Hsueh-chao & Nation, 2000). In an attempt to address this need, Coxhead (2000) developed the Academic Word List (AWL)—a list of words common across a range of academic disciplines; however, Gardner & Davies (2014) identified potential limitations in the AWL and have more recently produced their own list of core academic vocabulary—the Academic Vocabulary List (AVL). This study compares the occurrences of the AWL and AVL word families in an intensive English program (IEP) corpus of 50 texts to …


Busemann G-Spaces, Cat(K) Curvature, And The Disjoint (0, N)-Cells Property, Clarke Alexander Safsten Jul 2017

Busemann G-Spaces, Cat(K) Curvature, And The Disjoint (0, N)-Cells Property, Clarke Alexander Safsten

Theses and Dissertations

A review of geodesics and Busemann G-spaces is given. Aleksandrov curvature and the disjoint (0, n)-cells property are defined. We show how these properties are applied to and strengthened in Busemann G-spaces. We examine the relationship between manifolds and Busemann G-spaces and prove that all Riemannian manifolds are Busemann G-spaces, though not all metric manifolds are Busemann G-spaces. We show how Busemann G-spaces that also have bounded Aleksandrov curvature admit local closest-point projections to geodesic segments. Finally, we expound local properties of Busemann G-spaces and define a new property which we call the symmetric property. We show that Busemann …


Family Environments And Children's Cognitive Skills: Accounting For Heritable Influences Through Comparing Adopted And Biological Children, Shelby Mae Mcneill Jul 2017

Family Environments And Children's Cognitive Skills: Accounting For Heritable Influences Through Comparing Adopted And Biological Children, Shelby Mae Mcneill

Theses and Dissertations

Utilizing ECLS-K:2011 data, this study compares adopted and biological children to account for the role of heritable characteristics in explaining the relationship between family environments and children's cognitive skills. I find that cognitive skills do not differ across adopted and biological children after adjusting for the systematic differences between them. I also find that the relationship between family environment and children's cognitive skills does not differ across adopted and biological children. Taken together, these results suggest that the relationship between family environment and children's cognitive skills is not spurious.


A Case Study On The Facilitation Of Positive Behavior Interventions And Supports In A Public Elementary School, John T. Shumway Jul 2017

A Case Study On The Facilitation Of Positive Behavior Interventions And Supports In A Public Elementary School, John T. Shumway

Theses and Dissertations

Disruptive behaviors in elementary schools are a serious concern for teachers. With mounting pressure from school district administrations, state and federal government agencies, and the communities in which these schools reside, teachers often struggle to determine the best path to achieve consistent student engagement. When inappropriate behaviors are not managed effectively, academics suffer. Positive behavior interventions and supports (PBIS) have been shown to be effective in reducing such behaviors. Professional Learning Communities (PLC) have also become very common in schools as teachers are organized into teams to collaborate and plan learning opportunities and methods for the instruction and assessment of …


Continuous Permeability Measurement During Unidirectional Vacuum Infusion Processing, David Wayne Hoagland Jul 2017

Continuous Permeability Measurement During Unidirectional Vacuum Infusion Processing, David Wayne Hoagland

Theses and Dissertations

Composite materials have traditionally been used in high-end aerospace parts and low-end consumer parts. The reason for this separation in markets is the wide gap in technology between pre-preg materials processed in an autoclave and chop strand fiberglass blown into an open mold. Liquid composite molding has emerged as a bridge between inexpensive tooling and large, technical parts. Processes such as vacuum infusion have made it possible to utilize complex layups of reinforcement materials in an open mold style set-up, creating optimal conditions for composites to penetrate many new markets with rapid innovation. Flow simulation for liquid composite molding is …


Examining The Effect Of Friends' Drug Treatment On One's Drug Use: Investigating Positive Peer Influence In The National Longitudinal Study Of Adolescent To Adult Health, Dallin C. Everett Jul 2017

Examining The Effect Of Friends' Drug Treatment On One's Drug Use: Investigating Positive Peer Influence In The National Longitudinal Study Of Adolescent To Adult Health, Dallin C. Everett

Theses and Dissertations

Peer influence is a well-studied and established phenomenon in the social sciences with much research focusing on peers influencing one another in negative ways. However, peers have also been shown to provide a positive influence. Research on substance treatment programs indicates that one's social network can influence one to enter treatment as well as help maintain abstinence following the completion of the program. However, little is known about the influence that peer's drug treatment can have on the substance levels of an individual. I use the peer nomination data and Waves 1 and 2 of the National Longitudinal Study of …


Fundamental Studies And Applications Of Ambient Plasma Ionization Sources For Mass Spectrometry, Wade C. Ellis Jul 2017

Fundamental Studies And Applications Of Ambient Plasma Ionization Sources For Mass Spectrometry, Wade C. Ellis

Theses and Dissertations

The field of ambient desorption/ionization mass spectrometry (ADI-MS) has existed for over a decade. ADI-MS is a technique that offers benefits including fast analysis time, simple ionization sources that are easily constructed, and little to no required sample preparation. The research presented here describes efforts to better understand plasma-based ADI-MS sources and to explore the use of hydrogen-doped plasma gases with these sources. The use of hydrogen-doped argon (H2/Ar) and hydrogen-doped helium (H2/He) as plasma gases for a dielectric barrier discharge (DBD) and an AC glow discharge is presented first. When using the DBD, the intensity …


Ion Transport In A Commercial Icp-Ms, Jessica Joline Larsen Jul 2017

Ion Transport In A Commercial Icp-Ms, Jessica Joline Larsen

Theses and Dissertations

The performance of an inductively coupled plasma mass spectrometer, ICP-MS, depends on the instrument's ability to transport sample ions through the vacuum interface and focus the ions into a well-defined beam that will eventually reach the mass analyzer. In this study two main experiments were performed on the Perkin Elmer NexION 300S, a commercial ICP-MS. First, planar laser-induced fluorescence images were taken of the ion beam in a working instrument downstream from a unique quadrupole ion deflector. The images showed the ability of the instrument design to focus the ions in the ion beam. Second, laser-induced fluorescence was used to …


Lithofacies And Sequence Architecture Of The Lower Desert Creek Sequence, Middle Pennsylvanian, Aneth, Utah, Chanse James Rinderknecht Jul 2017

Lithofacies And Sequence Architecture Of The Lower Desert Creek Sequence, Middle Pennsylvanian, Aneth, Utah, Chanse James Rinderknecht

Theses and Dissertations

Middle Pennsylvanian (Desmoinesian) strata of the Lower Desert Creek (LDC) sequence within the sub-surface Greater Aneth Field (GAF) reflect a hierarchy of 4th and 5th order carbonate-dominated cycles. The Lower Desert Creek sequence, along the studied transect are composed of eight carbonate facies deposited on an east-facing shelf. There is a lateral transition from open marine algal buildup from the southeast (cores R-19, Q-16, O-16, and J-15) to a more restricted lagoonal environment to the northwest (core K-430 and E-313). The Lower Desert Creek sequence within the GAF contains three main parasequence sets: a basal, relatively deep-water unit (LDC 1), …


Curriculum Decisions And Reasoning Of Middle School Teachers, Anand Mikel Bernard Jul 2017

Curriculum Decisions And Reasoning Of Middle School Teachers, Anand Mikel Bernard

Theses and Dissertations

For decades curriculum materials have been used as a means to reform the manner in which mathematics is taught. In an attempt to better understand what impact curriculum materials have on the teaching and learning of mathematics, researchers have begun to analyze the process in which teachers transform curriculum materials into instruction. Given that many of these studies have been broad in nature, I sought to study the specific decisions that three teachers made when planning lesson on geometric transformation and their reasoning for those decisions. In this study I found that while the participants in this study ignored the …


An Examination Of The Psychometric Properties Of The Trauma Inventory For Partners Of Sex Addicts (Tipsa), Steven Scott Stokes Jul 2017

An Examination Of The Psychometric Properties Of The Trauma Inventory For Partners Of Sex Addicts (Tipsa), Steven Scott Stokes

Theses and Dissertations

This study examined the psychometric properties of the Trauma Inventory for Partners of Sex Addicts (TIPSA). Using the Nominal Response Model (NRM), I examined several aspects of item and option functioning including discrimination, empirical category ordering, and information. Category Boundary Discrimination (CBD) parameters were calculated to determine the extent to which respondents distinguished between adjacent categories. Indistinguishable categories were collapsed through recoding. Empirically disordered response categories were also collapsed through recoding. Findings revealed that recoding solved some technical functioning issues in some items, and also revealed items (and perhaps option anchors) that were probably poorly conceived initially. In addition, nuisance …


Using Advanced Psf Subtraction Techniques On Archival Data Of Herbig Ae/Be Stars To Search For New Candidate Companions, Emily Diane Safsten Jul 2017

Using Advanced Psf Subtraction Techniques On Archival Data Of Herbig Ae/Be Stars To Search For New Candidate Companions, Emily Diane Safsten

Theses and Dissertations

Herbig Ae/Be (HAeBe) stars are intermediate mass (2-10 solar mass) pre-main sequence stars with circumstellar disks. Observing planets within these young disks would greatly aid in understanding planet formation processes and timescales particularly around massive stars. So far, only one planet, HD 100546 b, has been confirmed to orbit a HAeBe star. With over 250 HAeBe stars known, and several observed to have disks with structures thought to be related to planet formation, it seems likely that there are as yet undiscovered planetary companions within the circumstellar disks of some of these young stars. Direct detection of a low-luminosity companion …


Relationship Between Using Korean Folktales In Foreign Language Class And Learners' Reading Comprehension And Cultural Understanding, Eunsun You Jul 2017

Relationship Between Using Korean Folktales In Foreign Language Class And Learners' Reading Comprehension And Cultural Understanding, Eunsun You

Theses and Dissertations

Language is a reflection of society, so knowing about a language also means knowing about a culture. Therefore, many types of literature have been used as a language education tool representing culture. This thesis proposed folktales as an effective material of not only introducing culture but also learning language. Since folktales are old stories that have passed from generation to generation for a long time, values and morals of a culture are naturally presented in the context of the stories. Furthermore, folktales could enhance students' reading comprehension because the story lines, phrases, and words in a story are used repeatedly. …


Function Of Ric-8a In G Protein E+- Subunit Biogenesis, Barry Willardson Jun 2017

Function Of Ric-8a In G Protein E+- Subunit Biogenesis, Barry Willardson

Journal of Undergraduate Research

  1. Grant Ludlam. The MEG award helped support Grant’s work from January 2015 through August 2016. During this time Grant has worked on three projects. He investigated the role of Ric8A in the folding of the G protein a subunit and its assembly into the G protein heterotrimeric complex. Unfortunately, his results showed that deletion of Ric8A in the photoreceptor cells of mice did not affect G protein signaling. As a result, he changed his research focus to determining the structure of the BBSome core complex. He assisted a graduate student, Takuma Aoba, in this work. They used a combination of …


Mentoring Undergraduates At The Intersection Of Organic Synthesis And Peptide Science, Steven L. Castle Jun 2017

Mentoring Undergraduates At The Intersection Of Organic Synthesis And Peptide Science, Steven L. Castle

Journal of Undergraduate Research

Our academic goals were threefold. First, we aimed to synthesize building blocks and begin assembling them to construct the anticancer peptide yaku’amide A (YA, Figure 1). Our purposes in synthesizing YA were to develop new chemical reactions suitable for efficiently preparing its unusual amino acids (shown in red and blue in Figure 1), and synthesize simplified analogues for use in studies designed to reveal its biological target and mode of action. Our second academic goal was derived from the first and involved investigating the ability of bulky dehydroamino acids (i.e., the amino acids of YA shown in blue in Figure …


A Novel Approach To A Big Simulation Problem: Creating Efficient Dry Granular Material Simulations With Accurate Visual Detail And Behavior, Seth Holladay Jun 2017

A Novel Approach To A Big Simulation Problem: Creating Efficient Dry Granular Material Simulations With Accurate Visual Detail And Behavior, Seth Holladay

Journal of Undergraduate Research

We received a MEG grant for researching the simulation of granular materials for computer graphics and animation. Materials such as sand and snow simulation is very expensive but necessary for productions, as well as hard to control the look, so I have been mentoring undergraduate and graduate students researching how to make sand simulations both efficient and art directable.


Alzheimer’S Disease: A New Model Defining The Mechanism Of Iron- Catalyzed Radical Damage To Neurons, Richard Watt, Jonathan Wisco Jun 2017

Alzheimer’S Disease: A New Model Defining The Mechanism Of Iron- Catalyzed Radical Damage To Neurons, Richard Watt, Jonathan Wisco

Journal of Undergraduate Research

The MEG proposal focused on understanding how elevated homocysteine levels cause the inability of cells to control iron levels as a cause for Alzheimer’s disease. Iron is associated with the amyloid plaques and tau tangles that are proposed to cause damage to neurons. Dr. Wisco and I previously submitted an NIH R15 proposal that was viewed positively but was not funded due to a lack of preliminary data. Our goal was to use MEG funding to provide preliminary data supporting the hypothesis. We proposed that Homocysteine was a dangerous trigger for disrupting iron metabolism. Biochemical techniques, immunohistochemistry techniques and MRI …


Dynamic Multi-Industry Firm Computational Model, Donald Rex Mcarthur, Rick Evans Jun 2017

Dynamic Multi-Industry Firm Computational Model, Donald Rex Mcarthur, Rick Evans

Journal of Undergraduate Research

My ORCA Grant allowed me to spend my time building a Macroeconomic Tax Policy scoring model that was used in open source research with the Tax Policy Center. I used the money to fund my time coding and contributing to the project found on the github repository at https://github.com/OpenSourcePolicyCenter. My focus was especially in developing the tax analysis on the side of the firms in the model. Under the direction of Rick Evans, we made some progress in that development, but it soon became apparent that the needed work was more based around the heterogeneous agents, and their respective income …


Effective Modeling Of The Distribution Of Wealth, Justin Gardiner, Richard Evans Jun 2017

Effective Modeling Of The Distribution Of Wealth, Justin Gardiner, Richard Evans

Journal of Undergraduate Research

Many macroeconomic models have trouble matching the high end of the distribution of wealth in the economy. To correct this problem, we set out to build a model that includes individual agents experiencing stochastic changes to their income levels. These stochastic changes thus model real life risk and encourage precautionary saving. We built the theoretical framework for a large scale macroeconomic model in which individuals take into consideration the possible variability of their future income and alter their saving behaviors accordingly. We have made significant progress in creating a computer program that will allow us to calibrate our model to …


International Trade Simulation, Jeff Clawson, Kerk Phillips Jun 2017

International Trade Simulation, Jeff Clawson, Kerk Phillips

Journal of Undergraduate Research

For the past year, this project has involved taking a trade simulation model, recreating it in a modern programming language and making it freely available through the Open Source Policy Center (OSPC). The program takes real world population data provided by the user and then simulates trade between countries. Unlike the natural sciences, Economists cannot always study their subjects in a controlled environment. Models like this project allow us to get an idea of what would happen, for example, in trade between the US and EU if there were to be a change in China’s taxes. Our project is still …


Minimum Required Detection Range For Detect And Avoid Of Unmanned Aircraft Systems, Jared Kevin Wikle, Tim Mclain, Randal W. Beard, Laith Rasmi Sahawneh Jun 2017

Minimum Required Detection Range For Detect And Avoid Of Unmanned Aircraft Systems, Jared Kevin Wikle, Tim Mclain, Randal W. Beard, Laith Rasmi Sahawneh

Faculty Publications

For unmanned aircraft systems to gain full access to the National Airspace System, they must have the capability to detect and avoid other aircraft. To safely avoid an- other aircraft, an unmanned aircraft must detect the intruder aircraft with ample time and distance to allow the ownship to track the intruder, perform risk assessment, plan an avoidance path, and execute the maneuver. This paper describes two analytical methods for finding the minimum detection range to ensure that these detection and avoidance steps can be carried out. The first method, time-based geometric velocity vectors, includes the bank-angle dynamics of the ownship; …


A Photometric Approach To The Redshift Of Galaxies, John Bohman, Joseph Moody Jun 2017

A Photometric Approach To The Redshift Of Galaxies, John Bohman, Joseph Moody

Journal of Undergraduate Research

It is necessary to study the distribution of matter to better understand the universe. There are many difficulties associated with this task however, one of the most basic being that that the universe is an extremely large space, and it takes a lot of time and effort to observe faint objects. Multi fiber spectrometers have made this task much easier, and over 1.4 million spectroscopic redshifts have been obtained. While this is certainly impressive, much remains to be done. This project attempts to develop a survey method capable of detecting and finding the redshift of relatively close (meaning a redshift …


Weak Synchronization In Excitatory – Inhibitory Neuronal Networks, Joel Eliason, Benjamin Webb Jun 2017

Weak Synchronization In Excitatory – Inhibitory Neuronal Networks, Joel Eliason, Benjamin Webb

Journal of Undergraduate Research

One ubiquitously observed dynamic phenomenon in the nervous system is that of weak synchronization or clustering, a behavior in which a large group of neurons in a population will all fire synchronously and then fall out of synchronization. When isolated to neurons that only form short-range connections, this behavior is typically referred to as “neuronal avalanches”, and is thought to be particularly important for robustness of information transmission as well as sensitivity to inputs. Given these potential computational benefits, avalanches have been a focus of theoretical biologists for the past 20 years. In particular, my project focused on the conditions, …


Identifying Binary Brown Dwarf Systems Using Model Point Spread Functions, Kyle Matt, Denise Stephens Jun 2017

Identifying Binary Brown Dwarf Systems Using Model Point Spread Functions, Kyle Matt, Denise Stephens

Journal of Undergraduate Research

The purpose of this project was to improve upon a method for discovering binary brown dwarf systems, and create a program to speed up the implementation of that method. A Brown Dwarf (BD) is a celestial object that is not massive enough to undergo hydrogen fusion in its core, meaning it is too small to be a star, but is also too big to be a planet. BDs can form in low-mass binary pairs. A stellar object located many parsecs away will act as a point source of light for an observer on Earth, therefore the light from such an …


Machine Learning With Scattering Transforms, Jacob Hansen, Gus Hart Jun 2017

Machine Learning With Scattering Transforms, Jacob Hansen, Gus Hart

Journal of Undergraduate Research

Our goal was to implement scattering transforms as a mathematical representation of materials. The intention of this project was to build intuition on this technique using model data in one and two dimensions. The tools created here will be used as templates in further projects on real materials data. The intuition built during this project is crucial to the machine learning framework for materials design that we hope to build in the near future.


Calculating Music Similarity With Mobile Device Playlists, Jacob O'Bryant, Dennis Ng Jun 2017

Calculating Music Similarity With Mobile Device Playlists, Jacob O'Bryant, Dennis Ng

Journal of Undergraduate Research

Music recommendation systems, such as Pandora and Spotify, help listeners to discover new music. The similarity of different songs is an important measure used in music recommendation. We have studied manually-created playlists on mobile devices to see if they can be used to accurately calculate song similarity. We collected playlists from 41 research subjects and used a co-occurrence model to calculate similarity between songs in the collection.


Using Frequency Noise Feedback To Satabilize Extended Cavity Diode Lasers For Use In Atomic Physics, Mckinley Pugh, Dallin Durfee Jun 2017

Using Frequency Noise Feedback To Satabilize Extended Cavity Diode Lasers For Use In Atomic Physics, Mckinley Pugh, Dallin Durfee

Journal of Undergraduate Research

Diode lasers in particular are useful in atomic physics because they are durable, compact, and relatively inexpensive. Unfortunately diode lasers also have linewidths that are much wider than atomic transitions. One common method to narrow the linewidth of diode lasers is to add a reflection grating outside the laser, creating an extended cavity diode laser (ECDL). While ECDLs are effective at narrowing the linewidth, they also introduce so many variables that affect the wavelength of the laser that small changes in the laser’s environment can cause the laser to mode hop, or jump to an entirely different wavelength.


Exact Nonparametric Inference For A Binary Endogenous Regressor, Joseph Cooprider, Brigham Frandsen Jun 2017

Exact Nonparametric Inference For A Binary Endogenous Regressor, Joseph Cooprider, Brigham Frandsen

Journal of Undergraduate Research

When there is endogeneity in an economic model, basic ordinary least squares regression analysis breaks down. Our assumptions for the model collapse so we cannot infer causality without bias in our estimations. Therefore, use of an instrumental variable is necessary. However, if instruments are weak, sample sizes are small, or assumptions about error terms are invalid, then our analysis is biased as well. We developed an exact, finite-sample approach to instrumental variables estimation and inference that remains valid for weak instruments, small samples, and other settings where large-sample approximations are poor. This approach imposed no parametric model for causal effects …


Characterizing Great Salt Lake Dust Relative Other Regional Dust Sources, Colin Hale, Carling Greg Jun 2017

Characterizing Great Salt Lake Dust Relative Other Regional Dust Sources, Colin Hale, Carling Greg

Journal of Undergraduate Research

Dust storms occur frequently along the Wasatch Front. These dust events may have negative effects on human health and agriculture. To help understand dust events along the Wasatch Front, this study focuses on analyzing dust deposition to better locate dust emission sources. Understanding the source of dust events is important. This is important because Great Salt Lake water levels are dropping exposing lakebed. This newly expose lakebed may result in increased frequency and intensity of dust events. To understand if this lakebed is affecting the Wasatch Front and acting as an emission source.