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Articles 1081 - 1110 of 2906

Full-Text Articles in Physical Sciences and Mathematics

Development Of A Surface Magneto-Optic Kerr Effect Magnetometer, Susan Stoffer Sorensen, Dr. Karine Chesnel Apr 2014

Development Of A Surface Magneto-Optic Kerr Effect Magnetometer, Susan Stoffer Sorensen, Dr. Karine Chesnel

Journal of Undergraduate Research

The Kerr effect is a phenomenon in which as polarized visible light reflects off of a magnetized surface it experiences a small rotation in polarization. This is known as the Kerr rotation, denoted Δθ. This rotation is proportional to the magnetization of the sample, to a first-order approximation (Δθ∝M). The surface magneto-optic Kerr effect (SMOKE) is a subset of the Kerr effect which probes the magnetization of the surface of the sample. Since the samples measured by our SMOKE apparatus are as thin as 10 nm to 100 nm the surface magnetization equals the total magnetization. These samples can be …

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Magnetic Symmetry-Mode Analysis Of La0.5 Ca0.5 Mno3, Eric Gibbs, Dr. Branton Campell Apr 2014

Magnetic Symmetry-Mode Analysis Of La0.5 Ca0.5 Mno3, Eric Gibbs, Dr. Branton Campell

Journal of Undergraduate Research

This project focuses on solving magnetic crystal structures using symmetry-mode analysis (SMA). A crystal is an arrangement of atoms in a repeating spatial pattern with the smallest repeating unit being known as the unit cell. A magnetic crystal contains atoms with a non-zero magnetic moment. A magnetic crystal’s unit cell repeats both the atomic and magnetic structure of the crystal. Neutron diffraction is a common method for studying magnetic crystals as the diffraction pattern can be used to determine the arrangement of atoms and magnetic moments within the unit cell.

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Psychoacoustic Effects Of High-Resolution Directivity Measurements On Room Modeling Auralizations, Nathan Eyring, Dr. Timothy Leishman Apr 2014

Psychoacoustic Effects Of High-Resolution Directivity Measurements On Room Modeling Auralizations, Nathan Eyring, Dr. Timothy Leishman

Journal of Undergraduate Research

Over the past years research has been conducted to understand how sound radiates from musical instruments. This has been done by recording a sphere of 2664 data points around a player through the process of many repetitions. This sphere is called the instrument’s directivity This data can be input into room modeling software to predict how an instrument will sound in any given location even before it is built. However there is the legitimate question of whether or not there this new data will change how room model sounds, and if someone listening would care. This research was an attempt …

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Developing Microwave-Generated Hydrogen Atoms As A Reducing Agent For Tungsten Atomic Layer Deposition, Jason Kyle Anderson, Dr. David Allred Apr 2014

Developing Microwave-Generated Hydrogen Atoms As A Reducing Agent For Tungsten Atomic Layer Deposition, Jason Kyle Anderson, Dr. David Allred

Journal of Undergraduate Research

Traditional micro fabrication processes are confined to a small subset of possible materials due to limitations on etching and are confined to low aspect ratio fabrication due to limits in both etching and stability of thicker film deposition processes.

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Modeling Supernovae Light Curves: A Vital Step Toward Photometric Classification, Brittany Spencer, Dr. Shane Reese Apr 2014

Modeling Supernovae Light Curves: A Vital Step Toward Photometric Classification, Brittany Spencer, Dr. Shane Reese

Journal of Undergraduate Research

Type Ia supernovae play a critical role in understanding the nature of the evolving universe. The Dark Energy Survey is currently investigating the expansion rate of the universe, with the intent to gain insight into the nature of dark energy. One of their primary measures of expansion is Type Ia supernovae (DES Projects, 2011). Due to this type of supernova’s uniformity in formation, most supernova of this type explode to approximately the same absolute brightness (Goobar, 2011).

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A Bayesian Nonparametric Approach To Hyperspectral Data Analysis, Jessica Seeger, Dr. Candace Berrett Apr 2014

A Bayesian Nonparametric Approach To Hyperspectral Data Analysis, Jessica Seeger, Dr. Candace Berrett

Journal of Undergraduate Research

Hyperspectral imaging (HSI) is a technology that provides a dense set of previously un- available data{o ering the opportunity for use in a variety of applications such as food safety, ecology, and non-proliferation research. HSI stores measurements across three dimen- sions (two-dimensional space and the electromagnetic spectrum), resulting in large, three- dimensional data cubes. This additional amount of information can be used to identify materials in the images remotely. However, due to the many possibilities for measurement and other errors, it is hard to distinguish between the signal (the material spectra) and these sources of noise. We combine a known …

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Asset Returns From A Distance-Based Random Partition Model, Richard D. Payne, David B. Dahl, Brian M. Hartman Apr 2014

Asset Returns From A Distance-Based Random Partition Model, Richard D. Payne, David B. Dahl, Brian M. Hartman

Journal of Undergraduate Research

When pricing an insurance product, many factors a ect market returns. Policyholder behavior (lapses, mortality, morbidity, etc.), policy riders (guarantees, look-backs, ratchets, etc.), industry and government forces (competition and regulation), among others can all depend on the asset returns and a ect the total risk exposure from the market. In these complicated settings, an analytical solution is often unavailable and the asset returns will need to be simulated. Regime- switching models are important in nance and actuarial science because they are often successful in simulating asset returns. These models t the complicated nature of market risk exposure more e ectively …

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Geomorphic Mapping And In Situ Analysis Of Avalanches On Loafer Mountain, Kimball Hansen, Dr. Matthew Bekker Apr 2014

Geomorphic Mapping And In Situ Analysis Of Avalanches On Loafer Mountain, Kimball Hansen, Dr. Matthew Bekker

Journal of Undergraduate Research

The goal of this project was continue the previous avalanche chronology of Loafer Mountain that my mentor professor started and had me finish in 2011. We wanted to incorporate using Geographic Information Systems (GIS) which could help us find better results for our avalanche chronology. By using a GIS we can map our samples and thus provide a more in-depth analysis of the avalanche path by providing the width and magnitude.

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Religious Balance In The Middle East: A Study On How Geography Influences Christian Tolerance In The Jordan State, Conor Fishback, Dr. Chad Emmett Apr 2014

Religious Balance In The Middle East: A Study On How Geography Influences Christian Tolerance In The Jordan State, Conor Fishback, Dr. Chad Emmett

Journal of Undergraduate Research

Recently three of Jordan’s neighboring states: Israel, Iraq, and Syria have experienced different types of large scale violence within their country. Jordan has remained relatively stable with no major violent conflicts. On October 21st 2012, the Jordanian Government announced that it had foiled a terrorist plot involving 11 Jordanians seeking to target Western interests in Amman. Even though Jordan is near the heart of the Muslim world, it has been targeted by terrorists, as if it was a Western state. This study analyzed the level of tolerance to the Christian faith inside a Muslim state according to the location of …

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Using Head-¬‐Mounted Displays To Teach Deaf Students In Planetariums, Holly Mumford Apr 2014

Using Head-¬‐Mounted Displays To Teach Deaf Students In Planetariums, Holly Mumford

Journal of Undergraduate Research

During the Summer of 2012 we were able to conduct preliminary tests of HMD’s with deaf children ages 7-­‐17. Many of these were volunteers from EFY. Each subject watched a prepared video segment on the Earth, Sun and Moon, from Evans & Sutherland. They were accompanied by a translator, and ASL fluent facilitators and tech specialists. After these sessions were completed the subjects participated in a group discussion. We gained good insight and positive feedback. Once these sessions were finished I helped develop the coding system we would use in evaluating the videos, and analyzed the results.

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Increasing User Password Strength By Introducing Group Dynamics, Lee J. Hinkle, Arthur Weagle, Spencer Bean Apr 2014

Increasing User Password Strength By Introducing Group Dynamics, Lee J. Hinkle, Arthur Weagle, Spencer Bean

Journal of Undergraduate Research

Password strength is an issue of growing concern.

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Characterization Of Peptides That Cause Ribosome Stalling, Diana Valverde, Dr. Allen Buskirk Apr 2014

Characterization Of Peptides That Cause Ribosome Stalling, Diana Valverde, Dr. Allen Buskirk

Journal of Undergraduate Research

The ribosome is a macromolecular machine found in all living cells. It catalyzes protein synthesis through a process known as translation. The ribosome reads messenger RNA that carries the blueprint for a protein product and brings in the appropriate amino acids to build a specific protein. Ribosomes are composed of two subunits (50S and 30S) that form three binding sites for transfer RNA. The A site of the ribosome accepts the incoming tRNA charged with an amino acid. This tRNA transfers its amino acid to a growing polypeptide chain held in the P site. After the transfer, the tRNA exits …

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Design And Synthesis Of (-)- Englerin A Mimics, Kayleen Thompson, Dr. Merritt Andrus Apr 2014

Design And Synthesis Of (-)- Englerin A Mimics, Kayleen Thompson, Dr. Merritt Andrus

Journal of Undergraduate Research

Englerin A, which comes from an East African plant, Phyllantus englari, has been found to be an impressive anti-renal cancer agent. It is even more promising than another leading natural anticancer agent, Taxol.1 Englerin A has a unique, complex structure, and its exact mode of action is currently unknown. The key features of englerin A are the cinnamate ester and glycolate ester with an intervening lipophilic cyclic hydrocarbon core. The englerin structure can be effectively mimicked with a more simplified core structure. For this project, I worked on synthesizing an analog of the anticancer agent (-)-englerin A that contains key …

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Searching For Nascent Peptides That Cause Ribosome Stalling, Shankar Parajuli, Dr. Allen Buskirk Apr 2014

Searching For Nascent Peptides That Cause Ribosome Stalling, Shankar Parajuli, Dr. Allen Buskirk

Journal of Undergraduate Research

Ribosomes are molecular machines that synthesize all the proteins for all living cells. Ribosomes sometimes stall and cannot complete the synthesis of a given protein. Some peptides interact with the ribosome during their own translation and induce stalling.1 The SecM and TnaC peptides in E. coli, for example, have been found to play a key regulatory role in translation of genes found on the same mRNA.2

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Synthesis And Purification Of The Glycosphingolipid Csa-13, Tyler Olsen, Dr. Paul Savage Apr 2014

Synthesis And Purification Of The Glycosphingolipid Csa-13, Tyler Olsen, Dr. Paul Savage

Journal of Undergraduate Research

The need for novel antibiotic mechanisms is prevalent. Common antimicrobial medicines such as penicillin, ampicillin and vancomycin have started becoming obsolete as resistant strains of bacteria become more widespread. The main problem with antibiotics is the rapid mutations that bacteria undergo. Eventually one cell will develop resistance, and then have that mutation selected for as patients undergo antibiotic therapy. Bacteria are rapidly changing to combat the many new antibiotic variants that have come out.

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Electrospray Of Bacteria Intact And Viable, Sara Pratt, Dr. Daniel Austin Apr 2014

Electrospray Of Bacteria Intact And Viable, Sara Pratt, Dr. Daniel Austin

Journal of Undergraduate Research

In this project we wanted to see if bacteria can survive a process called electrospray ionization (ESI). While bacteria survival of ESI has not previously been demonstrated, viruses survivability has1. The process of ESI consists of spraying a solution of the desired analyte in a strong electric field. Solution flowing through a capillary forms a Taylor cone at the end from which charged droplets emit. As solvent evaporates, the droplets break apart. As solvent continues to evaporate, that process is repeated and eventually forms individually charged particles once all the solvent is evaporated. The ESI in this experiment is done …

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Bioactive Lipid Analysis Of Asthma-Induced Lung Tissue With A Focus On Biomarker Identification, Mackay Merrill, Dr. John Prince Apr 2014

Bioactive Lipid Analysis Of Asthma-Induced Lung Tissue With A Focus On Biomarker Identification, Mackay Merrill, Dr. John Prince

Journal of Undergraduate Research

Initially, the goal of my project was to search for biologically active lipids in the lung tissue of mice with and without asthma (as opposed to those which simply form the membranes of cells) and determine if any of these lipids could serve as indicators of the disease. Over the course of experimentation, the focus shifted to these membrane (or structural) lipids. I planned to find indicative lipids (biomarkers) using mass spectrometry and statistical analysis.

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Follicular Dendritic Cells And Activation Of T Cells Bearing Latent Hiv, Jared Huber, Dr. Gregory F. Burton Apr 2014

Follicular Dendritic Cells And Activation Of T Cells Bearing Latent Hiv, Jared Huber, Dr. Gregory F. Burton

Journal of Undergraduate Research

Determine the pathway by which FDC cytokines activate HIV transcription in CD4+ T‐cells harboring latent HIV.

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Attribute Extraction For Web Page Clustering In Web People Searches, Joseph Park, Dr. David Embley Apr 2014

Attribute Extraction For Web Page Clustering In Web People Searches, Joseph Park, Dr. David Embley

Journal of Undergraduate Research

The disambiguation of person names in web people searches is a long standing problem within the semantic search community. A query such as the name “Henry Eyring” would produce thousands of results with references to more than one entity with that same name. In order to mitigate this problem, person-related attributes such as birth dates are extracted and used to group pages that refer to the same entity. The level of confidence that the pages are correctly grouped together is thus directly dependent upon the level of confidence that the person-related attributes were correctly extracted and properly associated to the …

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Major Earthquakes In Tsunamic Of The Banda Arc Region, Indonesia: The Past 400 Years, Tsz Man Fisher (Lau), Dr. Ronald Harris Apr 2014

Major Earthquakes In Tsunamic Of The Banda Arc Region, Indonesia: The Past 400 Years, Tsz Man Fisher (Lau), Dr. Ronald Harris

Journal of Undergraduate Research

The original project was titled, “Journey to the Center of the Earth: Investigating Subduction Channel Processes in Southern Tibet.” Complications came up when we began to work on this project last summer. With the permission of the ORCA committee, we changed the project into tsunami modeling instead of investigating subduction channel in Tibet.

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Microelectromechanical Devices For Remote Sensing In Extreme Conditions, David Landry, Dr. David Allred Apr 2014

Microelectromechanical Devices For Remote Sensing In Extreme Conditions, David Landry, Dr. David Allred

Journal of Undergraduate Research

Microelectromechanical systems (MEMS) are commonly used to build sensors for consumer products such as game console controllers1 and smart phones2. These sensors use piezoelectric materials and are wired directly into a larger electronic system. Because of their use case, these sensors are designed to operate near room temperature. The goal of this project was to help create a remotely detected MEMS accelerometer capable of operating in high temperature and high acceleration environments.

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Lithium-6 Neutron Detector, Adam Wallace, Dr. Lawrence Rees Apr 2014

Lithium-6 Neutron Detector, Adam Wallace, Dr. Lawrence Rees

Journal of Undergraduate Research

Over the last year I have built several neutron detectors with lithium-6 glass and tested their efficiency. As stated in my proposal, this detector is being designed for use by the United States Department of Homeland Security (DHS) at portal monitors. In order to meet their requirements we had to test our detectors for neutron detection efficiency and minimize their sensitivity to gamma radiation.

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High-Aspect Ratio Microaccelerometer For Extreme Environments, Adam Konneker, Dr. David Allred Apr 2014

High-Aspect Ratio Microaccelerometer For Extreme Environments, Adam Konneker, Dr. David Allred

Journal of Undergraduate Research

Over the course of the past year, I have had the invaluable opportunity to pursue a research project under the guidance of Dr. David Allred. I am still working on completing the project, but I have made significant progress and gained experience in designing microscale devices. The original goal of my research project was to design and build a microscale acceleration sensor, or accelerometer, capable of operating in extreme environments, which is to say in high temperatures and corrosive atmospheres. This project is one piece of a larger goal, which is to make wireless sensors for extreme environments. Thus far, …

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The Calculation Of H-Beta Indices For Delta Scuti Variable Stars, Kelsey Jorgenson, Dr. Eric Hintz Apr 2014

The Calculation Of H-Beta Indices For Delta Scuti Variable Stars, Kelsey Jorgenson, Dr. Eric Hintz

Journal of Undergraduate Research

A large part of astronomical research involves gathering information about celestial objects and drawing conclusions about that information. Astronomers commonly gather data for research projects via sweeping surveys, either of particular regions of the sky or of specific kinds of stars or celestial objects. Data from these surveys are often arranged into catalogues. The aim of my research project was to fill in information gaps in the catalogue of information of known delta Scuti variable stars, particularly in the form of the hydrogen beta, or H-beta, index. I will give introductory information about delta Scuti stars as well as the …

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Fabrication Of Suspended Graphene Membranes Grown By Chemical Vapor Deposition (Cvd) Using Carbon Nanotubes, Caleb Hustedt, Dr. Robert Davis, Dr. Richard Vanfleet Apr 2014

Fabrication Of Suspended Graphene Membranes Grown By Chemical Vapor Deposition (Cvd) Using Carbon Nanotubes, Caleb Hustedt, Dr. Robert Davis, Dr. Richard Vanfleet

Journal of Undergraduate Research

Graphene is an exciting material that stands to have a large impact on the scientific community. Unfortunately, graphene cannot be fully utilized due to its small scale and time consuming production. Graphene grown by chemical vapor deposition solves these issues but comes with a cost of decreased mechanical and electrical properties due to defects. However, the exact properties of CVD graphene are not well quantified. In order to measure the qualities of CVD graphene it must be suspended. Carbon infiltrated carbon nanotube forests were fabricated with holes 2-20um in size. Imaging showed CVD graphene was suspended over up to 50 …

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Design And Implementation Of A Laser Locking Apparatus, Jarom Jackson, Dr. Dallin Durfee Apr 2014

Design And Implementation Of A Laser Locking Apparatus, Jarom Jackson, Dr. Dallin Durfee

Journal of Undergraduate Research

The experiment which we are building here in Dr. Durfee’s lab is a novel one, the key part of which is an ion interferometer. The interferometer consists of a beam of Sr+ ions which will be split in half. The two halves of the beam will travel along different paths, and then be recombined. Depending on the difference of phase of the two beams on recombining they may either constructively or destructively interfere with each other. Since the phase change of each beam depends on the potential energy along the path that beam follows, this will allow us to very …

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Biological Pathways In Determining Personalized Treatments, Ariana Hedges, Dr. W. Evan Johnson Apr 2014

Biological Pathways In Determining Personalized Treatments, Ariana Hedges, Dr. W. Evan Johnson

Journal of Undergraduate Research

At the current state of diagnostic capability, two patients with the same cancer diagnosis may respond very differently to the same treatment. Unfortunately, failure to respond to a particular treatment wastes valuable time and may result in disease progression that may be detrimental for the patient. Therefore, diagnoses finely tuned to individual patients would better guide treatment while eliminating the trial and error that is often part of current medical practice.

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Synthesis Of S-Equol Using Heck Coupling Reaction And Phase-Transfer Catalysis, Chelsey Hancock Apr 2014

Synthesis Of S-Equol Using Heck Coupling Reaction And Phase-Transfer Catalysis, Chelsey Hancock

Journal of Undergraduate Research

Please list all accomplishments, achievements, publications, presentations, or other scholarly productivity that resulted from your ORCA project. This may include submissions to peer-reviewed journals, conference presentations or papers, performances, exhibitions, internships, scholarships, graduate school opportunities, local presentations, or awards that followed your mentoring experience.

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Genetic Rescue Of The Irk 2 Knockout Phenotype By Ectopic Expression Of Irk 2 Wt, Brandon Gassaway, Dr. Emily Bates Apr 2014

Genetic Rescue Of The Irk 2 Knockout Phenotype By Ectopic Expression Of Irk 2 Wt, Brandon Gassaway, Dr. Emily Bates

Journal of Undergraduate Research

Anderson-Tawil Syndrome (ATS) is characterized by morphological defects including clinodactyly (abnormal curvature of digits), syndactyly (fused digits), micrognathia (small jaw), cleft palate, and hypertelorism (wide-set eyes) as well as periodic paralysis and heart arrhythmia. Mutations in inwardly rectifying potassium (Irk) channels are found in patients with ATS. Expression of mutant Irk channels causes similar physiological and morphological defects in mice.1

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Reactivation Of Latent Hiv In Cd4+ T Cells Through Fdc Costimulation, Matthew Greer, Dr. Greg Burton Apr 2014

Reactivation Of Latent Hiv In Cd4+ T Cells Through Fdc Costimulation, Matthew Greer, Dr. Greg Burton

Journal of Undergraduate Research

I received an ORCA grant for a project entitled “Reactivation of latent HIV in CD4+ T cells through FDC costimulation.” The original hypothesis of this research was that the factor FDCs (follicular dendritic cells) produce to reactivate latent HIV in T cells is a protein signaling molecule that can be identified through analyzing the proteins FDCs produce. While this project is still proceeding, my resources during the last year since I received an ORCA grant have been dedicated to ironing out a few preliminary wrinkles to this project. Specifically, I have troubleshot and optimized the method our lab group uses …

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