Physical Sciences and Mathematics | Open Access Articles

Modeling The Extended Low And Sudden High Periods Of Activity In Infectious Diseases, Dana Strong

Student Research Symposium

This research explores how the aggregation of individuals during disease spread may, in conjunction with noise, explain how some diseases’ trajectories spend some time at low numbers after which there is a sudden outbreak.

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Gpu Accelerated Preconditioning Of The Plasma Kinetic Equation, D. Caleb Price

Student Research Symposium

Solving the plasma kinetic equation provides higher-order moments to better approximate an accurate time evolution of plasma behavior contained in a tokamak. NIMROD seeks to produce code to simulate and model these macroscopic dynamics. Essential to this code’s efficiency is the preconditioning of matrices. I studied how compiling a GPU-enabled third-party library, SuperLU, would improve this preconditioning time for a test version of NIMROD's code. We found that the time of preconditioning decreased significantly when GPUs were allocated versus when only CPUs were, which provides understanding for the future utilization of GPUs by the NIMROD code directly.

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Detecting Climate Change In Trilobite Time, Michelle Norman

Student Research Symposium

Trilobites are a signature marine fossil of the Cambrian explosion, which took place about 500 Ma (million years ago). By studying these fossiliferous rocks (limestone), we can get an understanding of ecological and environmental change. In fact, we can detect the ancient carbon cycle by measuring stable carbon isotopes in these limestone samples. By studying the carbon environment the trilobites lived in and which trilobite species evolve or go extinct, we can learn more about ancient climate events and constrain them to a certain period of time based off the age of radioactive zircons we find in sandy material around …

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Preparation And Characterization Of Highly Insulating Granular Samples For Electron Yield Measurement, Heather Allen

Student Research Symposium

This experiment focuses primarily on the preparation and characterization of granular samples for the eventual purpose of electron yield measurements. Highly insulating granular samples are notoriously difficult to prepare and present a myriad ofcomplications from both experimental and practical frameworks. A famous example of this was during the 1969 Apollo 11 mission when electrostatically adhered lunar dust damaged the equipment and astronauts suits and led to purported health effects. The electrical properties of this dust for charging and discharge is essential to preventing these effects. In this study, particles of varying size, shape, and composition are used to create multilayered …

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Seasonal Variations In Global Ionospheric Total Electron Content (Tec), Jason Knudsen

Student Research Symposium

As the Sun ionizes atoms and molecules in the Earth’s ionosphere, the region of atmosphere above approximately 100 km in altitude, the created ionization in this region affects many of the systems that we rely on in daily life. This includes cellular service, GPS navigation, weather forecasting, and credit card data. A good measure for the level of ionization in the ionosphere is the total electron content (TEC), which is the number of electrons in a one square meter column above a given location. The TEC over a geographic location influences the propagation of radio waves that traverse that section …

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Rayleigh Scattering Is The Reason The Sky Is Blue, Samuel Monson

Student Research Symposium

In this experiment what is examined is light scattering. What was done was taking a spectrometer and taking in the sunlight over long periods of time. The goal here is to both identify and determine when Rayleigh or Mie Scattering is taking place. In Rayleigh scattering what should appear is blue light, and in Mie other kinds of light should be observed.

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The Effects Of Absorbed Water On Electrostatic Breakdown Testing, Megan Loveland Dewaal

Student Research Symposium

A critical property of electrical insulators is the breakdown voltage. When exposed to a high enough voltage, the insulator will be permanently damaged and unable to block significant current flow which can lead to the compromise of important electrical equipment. This becomes a concern for applications like spacecraft missions, high voltage direct current power, and microelectronics, as well as many others. Recent preliminary tests suggested that water vapor on the surface of insulators may increase their breakdown voltage and influence phenomena observed during breakdown testing, such as partial discharges, partial breakdowns, and surface flashovers. In this study, thin film PEEK …

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Application Of Acceleration Data To Inertial Navigation, Eric Eastham

Student Research Symposium

In many fields, there exists a need for knowing the precise location of an object. In many cases, the Global Positioning System can be used to determine the precise location of an object, and even its speed and acceleration, to an accuracy of within 10 to 30 feet. In some cases however, such as in applications in space exploration, this is unavailable. Without reference to exterior points, inertial navigation can be a useful tool to determine an object's current location based on the prior movement and rotational changes made. The position is determined by taking the accelerations throughout the course …

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The Effects Of Moisture On The Conductivity Of M55j Carbon Fiber Composites, Crystal Tingle

Student Research Symposium

In this research, we studied the effects that humidity (moisture) can have on M55J Carbon Fiber Composite samples.

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Icon Satellite Measurements, Uncertainty, And Error Calculations, Benjamin Bradshaw

Student Research Symposium

NASA's satellite the Icon (Ionospheric Connections Explorer) is a satellite launched in 2019 to better understand the connection between Earth's atmosphere and the space environment. Though its systems were tested before launching further validation of its measurements are needed. This is accomplished through using USU's NA Lidar systems measurements over similar regions. USU's Na Lidar is a robust instrument that has been shown to be valid for many years. Through this comparison Icon's measurements have been shown to not be very precise at its lower measurements regions as it fails to measure a distinct temperature fluctuation around 92 km.

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Detonation Of A White Dwarf Star: Simulations Of The Sub-Chandrasekhar Type 1a Supernovae, Melissa Rasmussen

Student Research Symposium

A type Ia supernova can result from the double detonation of a white dwarf star below the Chandrasekhar mass limit. Using the hydrodynamics code Castro, we simulate this detonation by perturbing a carbon/oxygen white dwarf with an accumulated shell of helium, with a small amount of nitrogen-14. In this work, we investigate the robustness of the model. Adjusting the location of the perturbation affects whether detonation occurs. Changing the composition of the helium shell affects the speed at which it burns. The size of the reaction network used affects whether the star's core burns immediately or from a shock wave …

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Simultaneous Simulation Of Microgravity And Ionizing Radiation In A Laboratory Environment, Achal Duhoon

Student Research Symposium

A novel system was developed to simulate the combined effects of reduced gravity and ionizing radiation present during spaceflight on biological and particulate samples. The miniature rotary cell culture system (mRCCS) was designed to synchronously rotate up to five independent vessels containing particulate samples suspended in fluid media, constructed using radiation tolerant, biocompatible, and vacuum compatible materials. Reduced gravity conditions were achieved when suspended particles (e.g., 200 μm polystyrene microcarrier beads with or without adhered cell clusters) were suspended inside the vessels moving near terminal velocity in viscous neutral-buoyant fluid media with densities matched to the suspended particles to achieve …

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Asymptotic Mean-Value Formulas For Solutions Of General Second-Order Elliptic Equations, Pablo Blanc, Fernando Charro, Juan J. Manfredi, Julio D. Rossi

Mathematics Faculty Research Publications

We obtain asymptotic mean-value formulas for solutions of second-order elliptic equations. Our approach is very flexible and allows us to consider several families of operators obtained as an infimum, a supremum, or a combination of both infimum and supremum, of linear operators. The families of equations that we consider include well-known operators such as Pucci, Issacs, and k-Hessian operators.

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Spatial And Temporal Variations Of Microplastic Concentrations In Portland's Freshwater Ecosystems, Rebecca Talbot, Elise F. Granek, Heejun Chang, Rosemary Wood, Susanne Brander

Geography Faculty Publications and Presentations

While microplastics are a pollutant of growing concern in various environmental compartments, less is known regarding the sources and delivery pathways of microplastics in urban rivers. We investigated the relationship between microplastic concentrations and various spatiotemporal factors (e.g., land use, arterial road length, water velocity, precipitation) in two watersheds along an urban-rural gradient in the Portland metropolitan area. Samples were collected in August, September, and February and were analyzed for total microplastic count and type. Nonparametric statistics were used to evaluate potential relationships with the explanatory variables, derived at both the subwatershed and near stream scales. In August, microplastic concentrations …

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Modeling The Spread Of Curly Top Disease In Tomato Crops, Rachel Frantz

Student Research Symposium

Curly Top disease (CT), caused by a family of curtoviruses, infects a wide variety of agricultural crops. Historically, CT has caused extensive damage in tomato crops resulting in substantial economic loss for the tomato industry. Control methods for CT are scarce, and methods for predicting and assessing the scope of CT outbreaks are limited. In this paper, we formulate two theoretical models, a deterministic model and a stochastic model, for the spread of CT in a heterogeneous environment consisting of beets (preferred host) and tomatoes. The models are composed of two susceptible classes and two infected classes (infectious beets and …

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Small-Scale “Atmospheric Perturbations” With A Horizontal Scale Of A Few Tens Of Meters, Jonas Hamrick

Student Research Symposium

The objective of this investigation isto identify and understand the small-scale atmospheric perturbations with a horizontal scale of a few tens of meters, based on a novel Na imager. These extremely small perturbations in this altitude range are believed to contribute considerably to the dynamics in the upper mesosphere and lower thermosphere, ranging between ~ 80 to 110 km. By changing the intensity of these Na images to mesospheric Na number density, we can derive the amplitudes of these perturbations based on the Na mixing ratios that provides a direct measure of the perturbation magnitudes. The perturbations of such scale …

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Characteristics Of Mesospheric Temperature And Gravity Waves Over Chile In 2020-2021, Damien Devitt

Student Research Symposium

Atmospheric gravity waves (AGWs) that propagate up into the mesospheric region break and transfer energy into the region. This energy process affects seasonal temperatures in the mesosphere and has important implications for rocket launches and GPS satellites. Using the Utah State University (USU) Mesospheric Temperature Mapper (MTM) located at the Andes Lidar Observatory (ALO) in Chile (30°S), wave activity and seasonal temperature changes were studied over the Andes Mountain Range from Jan 2020 to the first few months of 2021 for this study. The primary goal of the whole project was to continue the long-term data collection and analysis (since …

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Isotopic Analysis Of Hydrous Phenocrysts In Lava Flows Of The Peruvian Altiplano Plateau: Testing For A Subduction Signature, Alyssa Schiwal

Student Research Symposium

The process of flat-slab subduction introduces fluids directly into the overlaying lithosphere, leaving behind a unique stable isotope and trace element signature to the surrounding crust/mantle. Fluid alteration of the deep lithosphere can help explain geologic processes that are observed at the surface, such as patterns of crustal deformation (mountain building) and volcanism. The young high-K mafic volcanic rocks found in the Altiplano region of Southern Peru are derived from the melting of an altered mantle source. By analyzing the hydrogen stable isotopes as well as the trace elements of these volcanic rocks we can locate the water source associated …

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Manifold Alignment With Inter-Domain Diffusion, Andres Duque

Student Research Symposium

The integration of multimodal data presents a challenge in cases when the study of a given phenomena by different instruments or conditions generates distinct but related domains. In this paper, we propose Diffusion Transport Alignment (DTA) a semi-supervised manifold alignment method that exploits prior correspondence knowledge between distinct data views. DTA finds a bijection between two domains, which by assumption, share a similar geometrical structure coming from the same underlying data generating process. We empirically demonstrate the effectiveness of our method to integrate multimodal data, as well as how it can improve the performance of machine learning tasks, otherwise less …

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The Outdoor Fashion Industry Is Not Sustainable, Joshua Hillam

Student Research Symposium

Outdoor fashion companies are responsible for a large amount of waste and pollution worldwide. I believe they are ethically bound to make changes in their manufacturing process to decrease their footprint because their products are used in outdoor environments that are impacted negatively by waste and pollution. The fashion industry as a whole is responsible for 10% of the carbon emissions worldwide. Research was conducted by first understanding what being sustainable means from the EPA, from individuals who work in the fashion industry, and from companies that advocate for more sustainable clothing. I then investigated what materials are the most …

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Analyzing Suicidal Text Using Natural Language Processing, Cassandra Barton

Student Research Symposium

Using Natural Language Processing (NLP), we are able to analyze text from suicidal individuals. This can be done using a variety of methods. I analyzed a dataset of a girl named Victoria that died by suicide. I used a machine learning method to train a different dataset and tested it on her diary entries to classify her text into two categories: suicidal vs non-suicidal. I used topic modeling to find out unique topics in each subset. I also found a pattern in her diary entries. NLP allows us to help individuals that are suicidal and their family members and close …

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Evaluation Of Chelating Agents Used In Phytoextraction By Switchgrass Of Lead Contaminated Soil, Genna Hart, Marina Koether, Thomas C. Mcelroy, Sigurdur Greipsson

Open Access Publishing Fund Collection

Soil lead (Pb) contamination is a recognized environmental and global health problem. Phytoextraction of Pb using switchgrass (Panicum virgatum L.), a second-generation biofuel crop, is typically enhanced by soil chelation. The effectiveness of four different chelating agents, phytic acid (inositol hexaphosphate), citric acid, NTA (nitrilotriacetic acid), and EDTA (ethylenediaminetetraacetic acid) was examined in pot culture. Plants treated with EDTA (1 mM) showed significantly higher shoot Pb concentrations compared to control plants and plants treated with other chelates. Lead-solubility following phytoextraction was examined by soil washing using 0.01 and 0.05 M acetic acid as an extractant solution revealed no …

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Thickness Of Fluvial Deposits Records Climate Oscillations, Xiaoping Yuan, Laure Guerit, Jean Braun, Delphine Rouby, Charles Shobe

Faculty & Staff Scholarship

Fluvial deposits offer Earth’s best-preserved geomorphic record of past climate change over geological timescales. However, quantitatively extracting this information remains challenging in part due to the complexity of erosion, sediment transport and deposition processes and how each of them responds to climate. Furthermore, sedimentary basins have the potential to temporarily store sediments, and rivers subsequently rework those sediments. This may introduce time lags into sedimentary signals and obscure any direct correlation with climate forcing. Here, using a numerical model that combines all three processes—and a new analytical solution—we show that the thickness of fluvial deposits at the outlet of a …

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Butte Priority Soils Operable Unit (Bpsou) Draft 2021 Site-Wide Surface Water Monitoring Data Summary Report. Consent Decree- Civil Action No. Cv 89-039-Bu-She, Adrian Kien

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.

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Butte Priority Soils Operable Unit (Bpsou) Silver Bow Creek/Butte Area Npl Site, Atlantic Richfield Company

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.

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Terrestrial Carbon Isotope Stratigraphy And Mammal Turnover During Post-Petm Hyperthermals In The Bighorn Basin, Wyoming, Usa, Sarah J. Widlansky, Ross Secord, Kathryn E. Snell, Amy E. Chew, William C. Clyde

Department of Earth and Atmospheric Sciences: Faculty Publications

Paleogene hyperthermals, including the Paleocene–Eocene Thermal Maximum (PETM) and several other smaller events, represent global perturbations to Earth’s climate system and are characterized by warmer temperatures, changes in floral and faunal communities, and hydrologic changes. These events are identified in the geologic record globally by negative carbon isotope excursions (CIEs), resulting from the input of isotopically light carbon into Earth’s atmosphere. Much about the causes and effects of hyperthermals remains uncertain, including whether all hyperthermals were caused by the same underlying processes, how biotic effects scale with the magnitude of hyperthermals, and why CIEs are larger in paleosol carbonates relative …

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Pro-Inflammatory Diet Pictured In Children With Atopic Dermatitis Or Food Allergy: Nutritional Data Of The Lina Cohort, Olivia Schütte, Larissa Bachmann, Nitin Shivappa Mbbs, Mph, Ph.D., James R. Hébert Scd, Janine F. Felix, Stefan Röder, Ulrich Sack, Michaek Borte, Wieland Kiess, Ana C. Zenclussen, Gabriele I. Stangl

Faculty Publications

Background: Lifestyle and environmental factors are known to contribute to allergic disease development, especially very early in life. However, the link between diet composition and allergic outcomes remains unclear. Methods: In the present population-based cohort study we evaluated the dietary intake of 10-year-old children and analyses were performed with particular focus on atopic dermatitis or food allergy, allergic diseases known to be affected by dietary allergens. Dietary intake was assessed via semi-quantitative food frequency questionnaires. Based on these data, individual nutrient intake as well as children’s Dietary Inflammatory Index (C-DII™) scores were calculated. Information about atopic manifestations during the first …

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Atlantic Richfield Response To Agency Comments On The Draft Butte Priority Soils Operable Unit (Bpsou) 2021 Groundwater Monitoring Data Summary Report, January 2021 – December 2021; Dated April 8, 2022, Atlantic Richfield Company

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.

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Re: 2021 Butte Priority Soils Operable Unit (Bpsou) Draft Groundwater Monitoring Data Summary Report. Consent Decree- Civil Action No. Cv 89-039-Bu-She, Adrian Kien

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.

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Pre-Growth Environmental Stresses Affect Foodborne Pathogens Response To Subsequent Chemical Treatments, Amandeep Singh, Veerachandra K. Yemmireddy

School of Earth, Environmental, & Marine Sciences Faculty Publications

Foodborne pathogens such as Salmonella, E. coli O157:H7, and Listeria monocytogenes are known to survive under different environmental stresses with an effect on their physiological properties. The purpose of this study was to determine the effect of different environmental stresses on the foodborne pathogens response to subsequent chemical treatments. Three types of pathogens Salmonella, E. coli O157:H7, and Listeria monocytogenes were subjected to different environmental stresses: (i) Desiccation (ii) high salt (iii) low pH, and (iv) temperatures (14, 23, and 37 °C) during their growth. The cells harvested at their early stationary growth phase were subsequently subjected to chlorine (100 …

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Full-Text Articles in Physical Sciences and Mathematics

Modeling The Extended Low And Sudden High Periods Of Activity In Infectious Diseases, Dana Strong

Student Research Symposium

Gpu Accelerated Preconditioning Of The Plasma Kinetic Equation, D. Caleb Price

Student Research Symposium

Detecting Climate Change In Trilobite Time, Michelle Norman

Student Research Symposium

Preparation And Characterization Of Highly Insulating Granular Samples For Electron Yield Measurement, Heather Allen

Student Research Symposium

Seasonal Variations In Global Ionospheric Total Electron Content (Tec), Jason Knudsen

Student Research Symposium

Rayleigh Scattering Is The Reason The Sky Is Blue, Samuel Monson

Student Research Symposium

The Effects Of Absorbed Water On Electrostatic Breakdown Testing, Megan Loveland Dewaal

Student Research Symposium

Application Of Acceleration Data To Inertial Navigation, Eric Eastham

Student Research Symposium

The Effects Of Moisture On The Conductivity Of M55j Carbon Fiber Composites, Crystal Tingle

Student Research Symposium

Icon Satellite Measurements, Uncertainty, And Error Calculations, Benjamin Bradshaw

Student Research Symposium

Detonation Of A White Dwarf Star: Simulations Of The Sub-Chandrasekhar Type 1a Supernovae, Melissa Rasmussen

Student Research Symposium

Simultaneous Simulation Of Microgravity And Ionizing Radiation In A Laboratory Environment, Achal Duhoon

Student Research Symposium

Asymptotic Mean-Value Formulas For Solutions Of General Second-Order Elliptic Equations, Pablo Blanc, Fernando Charro, Juan J. Manfredi, Julio D. Rossi

Mathematics Faculty Research Publications

Spatial And Temporal Variations Of Microplastic Concentrations In Portland's Freshwater Ecosystems, Rebecca Talbot, Elise F. Granek, Heejun Chang, Rosemary Wood, Susanne Brander

Geography Faculty Publications and Presentations

Modeling The Spread Of Curly Top Disease In Tomato Crops, Rachel Frantz

Student Research Symposium

Small-Scale “Atmospheric Perturbations” With A Horizontal Scale Of A Few Tens Of Meters, Jonas Hamrick

Student Research Symposium

Characteristics Of Mesospheric Temperature And Gravity Waves Over Chile In 2020-2021, Damien Devitt

Student Research Symposium

Isotopic Analysis Of Hydrous Phenocrysts In Lava Flows Of The Peruvian Altiplano Plateau: Testing For A Subduction Signature, Alyssa Schiwal

Student Research Symposium

Manifold Alignment With Inter-Domain Diffusion, Andres Duque

Student Research Symposium

The Outdoor Fashion Industry Is Not Sustainable, Joshua Hillam

Student Research Symposium

Analyzing Suicidal Text Using Natural Language Processing, Cassandra Barton

Student Research Symposium

Evaluation Of Chelating Agents Used In Phytoextraction By Switchgrass Of Lead Contaminated Soil, Genna Hart, Marina Koether, Thomas C. Mcelroy, Sigurdur Greipsson

Open Access Publishing Fund Collection

Thickness Of Fluvial Deposits Records Climate Oscillations, Xiaoping Yuan, Laure Guerit, Jean Braun, Delphine Rouby, Charles Shobe

Faculty & Staff Scholarship

Butte Priority Soils Operable Unit (Bpsou) Draft 2021 Site-Wide Surface Water Monitoring Data Summary Report. Consent Decree- Civil Action No. Cv 89-039-Bu-She, Adrian Kien

Silver Bow Creek/Butte Area Superfund Site

Butte Priority Soils Operable Unit (Bpsou) Silver Bow Creek/Butte Area Npl Site, Atlantic Richfield Company

Silver Bow Creek/Butte Area Superfund Site

Terrestrial Carbon Isotope Stratigraphy And Mammal Turnover During Post-Petm Hyperthermals In The Bighorn Basin, Wyoming, Usa, Sarah J. Widlansky, Ross Secord, Kathryn E. Snell, Amy E. Chew, William C. Clyde

Department of Earth and Atmospheric Sciences: Faculty Publications

Faculty Publications

Atlantic Richfield Response To Agency Comments On The Draft Butte Priority Soils Operable Unit (Bpsou) 2021 Groundwater Monitoring Data Summary Report, January 2021 – December 2021; Dated April 8, 2022, Atlantic Richfield Company

Silver Bow Creek/Butte Area Superfund Site

Re: 2021 Butte Priority Soils Operable Unit (Bpsou) Draft Groundwater Monitoring Data Summary Report. Consent Decree- Civil Action No. Cv 89-039-Bu-She, Adrian Kien

Silver Bow Creek/Butte Area Superfund Site

Pre-Growth Environmental Stresses Affect Foodborne Pathogens Response To Subsequent Chemical Treatments, Amandeep Singh, Veerachandra K. Yemmireddy

School of Earth, Environmental, & Marine Sciences Faculty Publications