Physical Sciences and Mathematics Commons^™

Rooted In Hell: Predicting Invasion Rates Of Phragmites Australis, Rachel Nydegger, Jacob P. Duncan, James A. Powell

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Across the estuaries of the east coast and wetlands of the Great Lakes, the invasive grass Phragmites australis outcompetes other vegetation and destroys local ecosystems. Because its roots are tolerant to salinity that other plants find hellish, Phragmites invasions begin with vegetative spread of genetic clones in brackish marshlands. This plant can grow over three meters tall at densities of 50 stems/m2, provides poor wildlife habitat, and is very difficult to eradicate.

A discrete life stage model on a yearly time step captures seed survivorship in a seed bank, sexual and asexual recruitment into a juvenile age class, and differential …

Addressing Light Pollution At Utah State University, Rachel Nydegger

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Many outdoor light fixtures illuminate in all directions, meaning that a large por- tion of light emitted is sent upwards. This excess of light light pollution – repre- sents wasted energy and money, decreases public safety, harms nocturnal and migra- tory animals, and destroys our view of the night sky. While Utah State University Facilities does have a program in place to retrofit light fixtures, and newly installed fixtures are chosen with light pollution in consideration, many of the light posts on campus continue to pollute the night sky. With the support of the Student Sustain- ability Offices Blue Goes …

Predicting Invasion Rates For Phragmites Australis, Rachel Nydegger, Jacob Duncan, James A. Powell

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In wetlands of Utah and southern Idaho as well as estuaries of the east coast, the ten-foot tall invasive grass Phragmites australis can be found near waterways, where it outcompetes native plants and degrades wildlife habitat. Phragmites australis is an obligate out-crossing plant that can spread sexually through seed disper- sal, or asexually via stolons and rhi- zomes (Kettenring and Mock 2012). Small patches are usually a single genetic individual, spreading vegetatively (and slowly) via runners; when patches become genetically diverse viable seeds are produced and invasion rates can be increase by an order of magnitude (Kettenring et al. 2011)

Stomatal Physics, Katie Sweet, Keith Mott, David Peak

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Stomata, microscopic pores on a leaf’s surface, regulate the diffusion of CO2 from, and the diffusion of water vapor to, the air.

Stomata are responsible for fixing essentially all carbon in the biosphere and generating over 90% of the water vapor in the atmosphere over landmasses.

Exactly how stomata respond to temperature, light intensity, and ambient CO2 and humidity, is still a matter of active debate.

Most research probing this question focuses on identifying and unraveling complicated biochemistry. Recent investigations in our laboratory, however, indicate that much of stomatal behavior can be understood in terms of a simple vapor phase …

Two-Dimensional Electron Gases At The Surface Of Potassium Tantalate, Ben Pound

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No abstract provided.

Characterizing And Quantifying Time Dependent Night Sky Brightness In And Around Tucson, Arizona, Rachel K. Nydegger, Constance E. Walker

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As part of a Research Experience for Undergraduates (REU) program with the National Optical Astronomy Observatory (NOAO), I (with mentor Dr. Constance Walker of NOAO) characterized light pollution in and near Tucson, Arizona using eight Sky Quality Meters (SQMs). In order to analyze the data in a consistent way for comparison, we created a standard procedure for reduction and analysis using python and MATLAB. The series of python scripts remove faulty data and examine specifically anthropogenic light pollution by excluding contributions made by the sun, moon, and the Milky Way. We then use MATLAB codes to illustrate how the light …

Annual Solar Motion And Spy Satellites, Margaret Jensen, Shane L. Larson

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A topic often taught in introductory astronomy courses is the changing position of the Sun in the sky as a function of time of day, and season. The relevance and importance of this motion is explained in the context of seasons and the impact it has on human activities such as agriculture. The geometry of the ob- served motion in the sky is usually reduced to graphical representations and visualizations that can be difficult to render and grasp. Sometimes students are asked to observe the Suns changing motion and record their data, but this is a long-term project requiring several …

Global Nightly Oh And O2 Mesospheric Airglow: Examining A Decade Of Measurements Using The Nasa Saber Satellite Sensor, Jonathan Price, Jordan C. Rozum, Gene Ware, Doran Baker

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The SABER instrument aboard the TIMED satellite is a multichannel radiometer and has been continuously measuring the altitude distribution of infrared airglow intensity in the mesosphere on a global basis since 2002. While the majority of these altitude distributions are Gaussian-like, a significant portion exhibit two or more local maxima, suggesting multiple airglow layers. To better understand the cause of this phenomenon, the global and temporal distributions of infrared OH andO2 scans resulting in multiple peak altitude profiles are being examined.

Functionalizing Carbon Nanotube Forests With 1,5-Diaminoaphthalene, Ben Pound, T. -C. Shen

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No abstract provided.

Understanding Light Pollution In And Around Tucson, Arizona, Rachel K. Nydegger

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No abstract provided.

Resolving Ionospheric E-Region Modeling Challenges: The Solar Photon Flux Dependence, Joseph B. Jensen, Jan J. Sojka, Michael David, Kent Tobiska, Robert W. Schunk, Tom Woods, Frank Eparvier

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The EVE instrument of the NASA Solar Dynamics Observatory (SDO) provides for the first time EUV and XUV measurements of the solar irradiance that adequately define the major source of ionization of the atmosphere. In our study we modeled the E-region of the ionosphere and analyzed how it is affected by the solar irradiance data obtained by EVE and contrast this with the S2000 Solar Irradiance model, used previously. The ionosphere has two major layers, the E-layer at 100 km, and the F-layer at 300 km. The difference in solar irradiances are small except at some wavelength bands, it is …

Quantifying Night Sky Fluctuations: Striving For A Multi-Messenger Astronomy, Rachel K. Nydegger, Shane L. Larson Ph.D.

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With LIGO coming back online soon, astronomers are attempting to solve the problems involved with coupling gravitational observations with electromagnetic telescope observations. To do this, my project aims to create all-sky surveys to characterize natural variability to reduce "false-alarm" rates in detections of gravitational emissions.

Small-Scale Simulation Chamber For Space Environment Survivability Testing, Robert H. Johnson, Lisa D. Montierth, Jr Dennison, James S. Dyer, Ethan R. Lindstrom

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A vacuum chamber was designed that simulates the space environment to facilitate tests of material modification due to space environment interactions. Critical environmental elements to be simulated include an ultra high vacuum, a FUV/UV/VIS/NIR solar spectrum, an electron plasma flux, temperature extremes, and long duration exposure. To simulate the solar electromagnetic spectrum (EMS), a solar simulator was used with a range of 200 nm to 2000 nm. A Krypton lamp provides surrogate radiation for the prominent far ultraviolet hydrogen Lyman-α 120 nm emission not produced by the solar simulator. A mono-energetic electron flood gun (20 eV to 15 keV) provides …

Multiple Peaks In Saber Mesospheric Oh Emission Altitude Profiles, Jordan Rozum, Gene A. Ware, Doran J. Baker, Martin G. Wlynczak, James M. Russell

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No abstract provided.

High-Frequency Pulsed-Electro-Acoustic (Pea) Measurements For Mapping Charge Distribution, Kristina Sorensen, Lee H. Pearson, Jr Dennison, Timothy E. Doyle, Kent D. Hartley

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No abstract provided.

Histological Analysis Of Biological Tissues Using High-Frequency Ultrasound, Kristina Sorensen, Tim Doyle, B. D. Borget, M. Cervantes, H, A. Chappell, B. J. Curtis, M. A. Grover, J. E. Roring, J. E. Stiles, L. A. Thompson

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No abstract provided.

Modeling Spiral Galaxy Luminosity Profiles, Jordan Rozum, Matt Garlock, Shane L. Larson, Bradley W. Carroll

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The distribution of spiral and bar galaxy inclination an- gles is expected to be uniform. However, analysis of sev- eral major galaxy catalogs shows this is not the case; galaxies oriented near edge-on are significantly more common in these catalogs. In an attempt to explain this discrepancy, we have developed a galaxy simulation code to compute the appearance of a spiral type galaxy as a function of its morphological parameters. We examine the dependence of observed brightness upon inclination angle by using smooth luminous mass density and in- terstellar medium (ISM) density distributions. The lu- minous mass component is integrated …

Characterizing Sky Variability For Multi-Messenger Astronomy, Rachel Nydegger, Katie Breivik, Shane L. Larson

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Multi-messenger astronomy employs both electromagnetic and gravitational wave detectors to paint a richer picture of celestial objects, providing more depth and in formation. Localizing sources with gravitational wave interferometers on the sky is difficult, with resolution of many square degrees. To have simultaneous electromagnetic observations (localized typically to less than one square degree) requires innovative techniques for the telescopes to find the origin of radiation. One idea is to tile the view of the interferometer, using multiple telescopes to simultaneously point at different areas of the field to observe the source. One problematic aspect of this observing paradigm is distinguishing …

The Rise Of Science In Japan: 日本科学発展と原因, Mario Harper

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日本の科学は第二次世界大戦から始まったと多くの人は思っている。もちろん、多くの発展は戦後に行われたのは事実。しかし、戦争以前にも「テクノロジージャパン」な考え方が非常に寿実していた。このスライドショーは日本科学発展の原因となることをいくつか見ています。

Histological Analysis Of Biological Tissues Using High-Frequency Ultrasound, Kristina Sorensen, Timothy Doyle, Brett D. Boret, Monica Cervantes, J. Andrew Chappell, Bradley J. Curtis, Matthew A. Grover, Janeese E. Stiles, Laurel A. Thompson

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No abstract provided.

Comparison Of Saber Oh Measurements To Rocket Photometry Data, Jordan Rozum, Gene A. Ware, Doran J. Baker

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In 2002, the Sounding of the Atmosphere us- ing Broadband Emission Radiometry (SABER) instru- ment aboard the Thermosphere Ionosphere Mesosphere Energetics and Dynamics (TIMED) satellite went online and has since been providing radiometric data concern- ing the mesosphere and lower thermosphere/ionosphere (MLTI) region of the atmosphere. Researchers at the Utah State University NASA Space Grant Consortium have been tasked with validating measurements of the hydroxyl airglow volume emission rates (VER) taken by SABER. To this end, we compare SABER measurements of the altitude distribution of hydroxyl airglow to mea- surements taken by photometers aboard rockets launched between 1961 and 1986 …

Comparison Of Saber Oh Measurements To Rocket Photometry Data, Jordan Rozum, Gene A. Ware, Doran J. Baker

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No abstract provided.

Full Isolation Number Of Matrices: Some Extremal Results, David Tate, David E. Brown

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A set of nonzero entries of a (0,1)-matrix is an isolated set if no two entries belong to the same row, no two entries belong to the same column, and no two entries belong to a submatrix of the form [1 1; 1 1]. The isolation number of a matrix is the maximum size over all isolated sets. The isolation number of a matrix is a well-known and well-used lower bound for the matrix's Boolean rank. We will discuss the isolation number of the adjacency matrix of various graphs and develop some extremal results for n x n matrices with …

Juggling By Numbers: Siteswap Notation For Juggling, David Tate

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A basic overview of the juggling notation known as "Siteswap". This is a way of describing juggling patterns using sequences of numbers.

Development Of Ultrasonic Detection Methods For Cancer Cells In Vivo, Jeffrey B. Goodrich

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A current problem in medicine and specifically breast cancer is the detection of microscopic cancer in surgical margins to ensure all of the cancer has been removed. Current methods rely on extensive pathology work that may take several days to complete. For breast cancer patients, positive findings for cancer in surgical margins require follow-up surgery to remove more tissue. Up to 50% of patients undergoing breast conservation surgery (lumpectomy) require additional surgery. A preferable method would be in vivo microscopic detection for use during surgery. Such methods would reduce risks, costs, and patient suffering that accompany follow-up operations. Ultrasound is …

Improved Methods For Teaching Science, Stephanie Peterson, Sara Scott

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Utah State University’s Get Away Special (GAS) team will conduct research aboard NASA's microgravity research aircraft, the “vomit comet,” through the Reduced Gravity Student Flight Opportunities program. Team members come from mechanical and aerospace engineering, computer science, physics, science education, and business backgrounds. The team will spend ten days this summer at NASA’s Johnson Space Center and perform experiments on the aircraft to better understand nucleate boiling, a potential method of efficient heat transfer in space.

Neuraminidase Activity Of Influenza Virus Strains That Differ In The Ability To Cause Disease, Benjamin Hanks Brown, Bart Tarbet

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Influenza viruses are classified based on their surface glycoproteins: hemagglutinin and neuraminidase. Hemagglutinin (HA) is responsible for binding to the host cell, while neuraminidase (NA) facilitates escape of newly formed virus particles. These studies determined the NA activity of three subtypes of influenza A virus that differ in their ability to cause disease in mice: influenza A/NWS/33 (H1N1), influenza A/Victoria/3/75 (H3N2), and influenza A/Duck/MN/1525/81 (H5N1). Chemiluminescent quantitation of NA activity in equal amounts of each virus was determined in three replicate experiments. Results indicate that N1 virus subtypes have higher NA activity than do N2 subtypes. In addition, the NA …