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Utah State University

2016

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Articles 1 - 30 of 221

Full-Text Articles in Physical Sciences and Mathematics

Electrocatalytic Valorization Of Biomass Intermediates Via 1st-Row Transition Metal Electrocatalysts, Yujie Sun Dec 2016

Electrocatalytic Valorization Of Biomass Intermediates Via 1st-Row Transition Metal Electrocatalysts, Yujie Sun

Funded Research Records

No abstract provided.


Diet And Lifetyle Factors Associated With Mirna Expression In Colorectal Tissue, Martha L. Slattery, Jennifer S. Herrick, Lila E. Mullany, John R. Stevens, Roger K. Wolff Dec 2016

Diet And Lifetyle Factors Associated With Mirna Expression In Colorectal Tissue, Martha L. Slattery, Jennifer S. Herrick, Lila E. Mullany, John R. Stevens, Roger K. Wolff

Mathematics and Statistics Faculty Publications

MicroRNAs (miRNAs) are small non-protein-coding RNA molecules that regulate gene expression. Diet and lifestyle factors have been hypothesized to be involved in the regulation of miRNA expression. In this study it was hypothesized that diet and lifestyle factors are associated with miRNA expression. Data from 1,447 cases of colorectal cancer to evaluate 34 diet and lifestyle variables using miRNA expression in normal colorectal mucosa as well as for differential expression between paired carcinoma and normal tissue were used. miRNA data were obtained using an Agilent platform. Multiple comparisons were adjusted for using the false discovery rate q-value. There were 250 …


Quantifying Gravity Wave Momentum Fluxes With Mesosphere Temperature Mappers And Correlative Instrumentation, David C. Fritts, Pierre-Dominique Pautet, Katrina Bossert, Michael J. Taylor, Bifford P. Williams, Hiroyuki Iimura, Tao Yuan, Nicholas J. Mitchell, Gunter Stober Dec 2016

Quantifying Gravity Wave Momentum Fluxes With Mesosphere Temperature Mappers And Correlative Instrumentation, David C. Fritts, Pierre-Dominique Pautet, Katrina Bossert, Michael J. Taylor, Bifford P. Williams, Hiroyuki Iimura, Tao Yuan, Nicholas J. Mitchell, Gunter Stober

Publications

An Advanced Mesosphere Temperature Mapper and other instruments at the Arctic Lidar Observatory for Middle Atmosphere Research in Norway (69.3°N) and at Logan and Bear Lake Observatory in Utah (42°N) are used to demonstrate a new method for quantifying gravity wave (GW) pseudo-momentum fluxes accompanying spatially and temporally localized GW packets. The method improves on previous airglow techniques by employing direct characterization of the GW temperature perturbations averaged over the OH airglow layer and correlative wind and temperature measurements to define the intrinsic GW properties with high confidence. These methods are applied to two events, each of which involves superpositions …


In-Class Versus At-Home Quizzes: Which Is Better? A Flipped Learning Study In A Two-Site Synchronously-Broadcast Organic Chemistry Course, Michael A. Christensen, Alyssia M. Lambert, Louis S. Nadelson, Kami M. Dupree, Trish A. Kingsford Dec 2016

In-Class Versus At-Home Quizzes: Which Is Better? A Flipped Learning Study In A Two-Site Synchronously-Broadcast Organic Chemistry Course, Michael A. Christensen, Alyssia M. Lambert, Louis S. Nadelson, Kami M. Dupree, Trish A. Kingsford

Chemistry and Biochemistry Faculty Publications

We recently shared our design of a two-semester flipped organic chemistry course, in which we gave students in-class quizzes to incentivize attendance and watching the lecture videos in advance. With a second iteration, we planned to make the video-watching experience more engaging. We accordingly hypothesized that if students completed short at-home quizzes while watching the videos, then attentiveness, engagement, and learning would increase. We tested this with a later section of the course, dividing the material into 13 units. For units 1-6, we gave in-class quizzes; for 7-13, quizzes were at home. Although units 1-6 and 7-13 covered different material, …


Foundations Of Wave Phenomena, Charles G. Torre Dec 2016

Foundations Of Wave Phenomena, Charles G. Torre

Charles G. Torre

This is an undergraduate text on the mathematical foundations of wave phenomena. Version 8.2.


Managing The Spread Of Alfalfa Stem Nematodes (Ditylenchus Dipsaci): The Relationship Between Crop Rotation Periods And Pest Re-Emergence, S. Jordan, Claudia Nischwitz, R. Ramirez, Luis F. Gordillo Dec 2016

Managing The Spread Of Alfalfa Stem Nematodes (Ditylenchus Dipsaci): The Relationship Between Crop Rotation Periods And Pest Re-Emergence, S. Jordan, Claudia Nischwitz, R. Ramirez, Luis F. Gordillo

Mathematics and Statistics Faculty Publications

Alfalfa is a critical cash/rotation crop in the western region of the United States, where it is common to find crops affected by the alfalfa stem nematode (Ditylenchus dipsaci). Understanding the spread dynamics associated with this pest would allow growers to design better management programs and farming practices. This understanding is of particular importance given that there are no nematicides available against alfalfa stem nematodes and control strategies largely rely on crop rotation to non-host crops or by planting resistant varieties of alfalfa. In this paper we present a basic host-parasite model that describes the spread of the …


Tutorial For Using The Center For High Performance Computing At The University Of Utah And An Example Using Random Forest, Stephen Barton Dec 2016

Tutorial For Using The Center For High Performance Computing At The University Of Utah And An Example Using Random Forest, Stephen Barton

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

Random Forests are very memory intensive machine learning algorithms and most computers would fail at building models from datasets with millions of observations. Using the Center for High Performance Computing (CHPC) at the University of Utah and an airline on-time arrival dataset with 7 million observations from the U.S. Department of Transportation Bureau of Transportation Statistics we built 316 models by adjusting the depth of the trees and randomness of each forest and compared the accuracy and time each took. Using this dataset we discovered that substantial restrictions to the size of trees, observations allowed for each tree, and variables …


On The Propagation Of Atmospheric Gravity Waves In A Non-Uniform Wind Field: Introducing A Modified Acoustic-Gravity Wave Equation, Ahmad Talaei Dec 2016

On The Propagation Of Atmospheric Gravity Waves In A Non-Uniform Wind Field: Introducing A Modified Acoustic-Gravity Wave Equation, Ahmad Talaei

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

Atmospheric gravity waves play fundamental roles in a broad-range of dynamical processes extending throughout the Earth’s neutral atmosphere and ionosphere. In this paper, we present a modified form for the acoustic-gravity wave equation and its dispersion relationships for a compressible and non-stationary atmosphere in hydrostatic balance. Importantly, the solutions have been achieved without the use of the well-known Boussinesq approximation which have been used extensively in previous studies.

We utilize the complete set of governing equations for a compressible atmosphere with non-uniform airflows to determine an equation for vertical velocity of possible atmospheric waves. This intricate wave equation is simplified …


Diet And Foraging Behaviors Of Timber Rattlesnakes, Crotalus Horridus, In Eastern Virginia, Scott M. Goetz, Christopher E. Petersen, Robert K. Rose, John D. Kleopfer, Alan H. Savitzky Dec 2016

Diet And Foraging Behaviors Of Timber Rattlesnakes, Crotalus Horridus, In Eastern Virginia, Scott M. Goetz, Christopher E. Petersen, Robert K. Rose, John D. Kleopfer, Alan H. Savitzky

Biology Faculty Publications

During a 17-yr telemetry study, we examined the diet and ambush behavior of a population of Crotalus horridus in southeastern Virginia. Forty dietary items were identified from 37 fecal samples. We documented 722 instances of snakes in an ambush posture, 61% of which were in a vertical-tree posture, as if hunting arboreal prey at the base of a tree. The most common prey items were Eastern Gray Squirrels (Sciurus carolinensis), which accounted for 45% of all dietary items and represented an estimated 78% of total biomass consumed by C. horridus. Prey was not consumed in proportion to availability, based on …


Temporal Foraging Patterns Of Nonnative Frogs (Eleutherodactylus Coqui) In Hawaii, Arthur C. Wallis, Robyn L. Smith, Karen H. Beard Dec 2016

Temporal Foraging Patterns Of Nonnative Frogs (Eleutherodactylus Coqui) In Hawaii, Arthur C. Wallis, Robyn L. Smith, Karen H. Beard

Wildland Resources Faculty Publications

The Puerto Rican Coqui Frog (Eleutherodactylus coqui) is a nocturnal, invasive species that was introduced into Hawaii in the 1980s. Because they reach extremely high densities (up to 90,000 frogs/ha), they have the potential to affect invertebrate prey communities. Previously, researchers used frogs collected only at night to characterize their prey. Because Coquis use retreat sites near the forest floor during the day and understory perch sites at night, frogs collected at night might show different amounts and types of prey than would frogs collected in the morning. We analyzed stomach contents of 435 frogs collected in the morning (0300–0600 …


Simple Soil Quality Tests And Organic Management Practices For Orchards In The Intermountain West, Esther Oline Thomsen Dec 2016

Simple Soil Quality Tests And Organic Management Practices For Orchards In The Intermountain West, Esther Oline Thomsen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Soil health is often overlooked as a long-term management strategy as growers face an increasing number of short-term management challenges in the Intermountain West. The costs of inputs are rising and water resources are becoming more limited. Soil with poor health typically requires more amendments and fertlizers to meet crop needs. Soil health tests can help reveal management practices that reduce soil health, as well as those that improve soil health. Practices known to improve soil health are reduced to no tillage, cover crop use- especially legumes, and addition of mulch and other organic materials. Soil health testing is not …


Statistical Techniques To Model And Optimize Performance Of Scientific, Numerically Intensive Workloads, Steena Dominica Steven Monteiro Dec 2016

Statistical Techniques To Model And Optimize Performance Of Scientific, Numerically Intensive Workloads, Steena Dominica Steven Monteiro

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Projecting performance of applications and hardware is important to several market segments—hardware designers, software developers, supercomputing centers, and end users. Hardware designers estimate performance of current applications on future systems when designing new hardware. Software developers make performance estimates to evaluate performance of their code on different architectures and input datasets. Supercomputing centers try to optimize the process of matching computing resources to computing needs. End users requesting time on supercomputers must provide estimates of their application’s run time, and incorrect estimates can lead to wasted supercomputing resources and time. However, application performance is challenging to predict because it is …


Laboratory Experiences In Mathematical Biology For Post-Secondary Mathematics Students, Matthew Lewis Dec 2016

Laboratory Experiences In Mathematical Biology For Post-Secondary Mathematics Students, Matthew Lewis

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In addition to the memorization, algorithmic skills and vocabulary which is the default focus in many mathematics classrooms, professional mathematicians are expected to creatively apply known techniques, construct new mathematical approaches and communicate with and about mathematics. We propose that students can learn these professional, higher level skills through Laboratory Experiences in Mathematical Biology (LEMBs) which put students in the role of mathematics researcher creating mathematics to describe and understand biological data. LEMBs are constructed so they require no specialized equipment and can easily be run in the context of a college math class. Students collect data and develop mathematical …


Ncer Assistance Agreement Annual Progress Report For Grant #83582401 - Assessment Of Stormwater Harvesting Via Manage Aquifer Recharge (Mar) To Develop New Water Supplies In The Arid West: The Salt Lake Valley Example, Ryan Dupont, Joan E. Mclean, Richard C. Peralta, Sarah E. Null, Douglas B. Jackson-Smith Nov 2016

Ncer Assistance Agreement Annual Progress Report For Grant #83582401 - Assessment Of Stormwater Harvesting Via Manage Aquifer Recharge (Mar) To Develop New Water Supplies In The Arid West: The Salt Lake Valley Example, Ryan Dupont, Joan E. Mclean, Richard C. Peralta, Sarah E. Null, Douglas B. Jackson-Smith

Civil and Environmental Engineering Faculty Publications

The aims of the original proposed project remain the same, that is, to test the hypothesis that Managed Aquifer Recharge (MAR) for stormwater harvesting is a technically feasible, socially and environmentally acceptable, economically viable, and permittable option for developing new water supplies for arid Western urban ecosystems experiencing increasing population, and climate change pressures on existing water resources. The project is being carried out via three distinct but integrated components that include: 1) Monitoring of existing distributed Managed Aquifer Recharge (MAR) harvesting schemes involving a growing number of demonstration Green Infrastructure (GI) test sites; 2) Integrated stormwater/vadose zone/groundwater/ ecosystem services …


Human Amplified Changes In Precipitation-Runoff Patterns In Large River Basins Of The Midwestern United States, Sara A. Kelly, Zeinab Takbiri, Patrick Belmont, Efi Foufoula-Georgiou Nov 2016

Human Amplified Changes In Precipitation-Runoff Patterns In Large River Basins Of The Midwestern United States, Sara A. Kelly, Zeinab Takbiri, Patrick Belmont, Efi Foufoula-Georgiou

Watershed Sciences Faculty Publications

Complete transformations of land cover from prairie, wetlands, and hardwood forests to homogenous row crop agriculture scattered with urban centers are thought to have caused profound changes in hydrology in the Upper Midwestern US since the 1800s. Continued intensification of land use and drainage practices combined with increased precipitation have caused many Midwest watersheds to exhibit higher streamflows today than in the historical past. While changes in crop type and farming practices have been well documented over the past few decades, changes in artificial surface (ditch) and subsurface (tile) drainage systems have not. This makes it difficult to quantitatively disentangle …


The Magnitude Of The Snow-Sourced Reactive Nitrogen Flux To The Boundary Layer In The Uintah Basin, Maria Zakto, Joseph Erbland, Joel Savarino, Lei Geng, Lauren Easley, Andrew Schauer, Timothy Bates, Patricia K. Quinn, Bonnie Light, David Morison, Hans D. Osthoff, Seth Lyman, William Neff, Bin Yuan, Becky Alexander Nov 2016

The Magnitude Of The Snow-Sourced Reactive Nitrogen Flux To The Boundary Layer In The Uintah Basin, Maria Zakto, Joseph Erbland, Joel Savarino, Lei Geng, Lauren Easley, Andrew Schauer, Timothy Bates, Patricia K. Quinn, Bonnie Light, David Morison, Hans D. Osthoff, Seth Lyman, William Neff, Bin Yuan, Becky Alexander

USU Uintah Basin Faculty Publications

Reactive nitrogen (Nr = NO, NO2, HONO) and volatile organic carbon emissions from oil and gas extraction activities play a major role in wintertime ground-level ozone exceedance events of up to 140 ppb in the Uintah Basin in eastern Utah. Such events occur only when the ground is snow covered, due to the impacts of snow on the stability and depth of the boundary layer and ultraviolet actinic flux at the surface. Recycling of reactive nitrogen from the photolysis of snow nitrate has been observed in polar and midlatitude snow, but snow-sourced reactive nitrogen fluxes in mid-latitude …


Dynamical Interactions Between Two Uniformly Magnetized Spheres, Boyd F. Edwards, John M. Edwards Nov 2016

Dynamical Interactions Between Two Uniformly Magnetized Spheres, Boyd F. Edwards, John M. Edwards

All Physics Faculty Publications

Studies of the two-dimensional motion of a magnet sphere in the presence of a second, fixed sphere provide a convenient venue for exploring magnet-magnet interactions, inertia, friction, and rich nonlinear dynamical behavior. These studies exploit the equivalence of these magnetic interactions to the interactions between two equivalent point dipoles. We show that magnet-magnet friction plays a role when magnet spheres are in contact, table friction plays a role at large sphere separations, and eddy currents are always negligible. Web-based simulation and visualization software, called MagPhyx, is provided for education, exploration, and discovery


Automated Calibration Of Atmospheric Oxidized Mercury Measurements, Seth Lyman, Colleen Jones, Trevor O'Neil, Tanner Allen, Matthieu Miller, Mae Sexauer Gustin, Ashley M. Pierce, Winston Luke, Xinrong Ren, Paul Kelley Nov 2016

Automated Calibration Of Atmospheric Oxidized Mercury Measurements, Seth Lyman, Colleen Jones, Trevor O'Neil, Tanner Allen, Matthieu Miller, Mae Sexauer Gustin, Ashley M. Pierce, Winston Luke, Xinrong Ren, Paul Kelley

USU Uintah Basin Faculty Publications

The atmosphere is an important reservoir for mercury pollution, and understanding of oxidation processes is essential to elucidating the fate of atmospheric mercury. Several recent studies have shown that a low bias exists in a widely applied method for atmospheric oxidized mercury measurements. We developed an automated, permeation tube-based calibrator for elemental and oxidized mercury, and we integrated this calibrator with atmospheric mercury instrumentation (Tekran 2537/1130/1135 speciation systems) in Reno, Nevada and at Mauna Loa Observatory, Hawaii, U.S.A. While the calibrator has limitations, it was able to routinely inject stable amounts of HgCl2 and HgBr2 into atmospheric mercury measurement systems …


Infrared Spectroscopy Of The Nitrogenase Mofe Protein Under Electrochemical Control: Potential-Triggered Co Binding, P. Paengnakorn, Philip A. Ash, Sudipta K. Shaw, Karamatullah Danyal, T. Chen, Dennis R. Dean, Lance C. Seefeldt, Kylie A. Vincent Oct 2016

Infrared Spectroscopy Of The Nitrogenase Mofe Protein Under Electrochemical Control: Potential-Triggered Co Binding, P. Paengnakorn, Philip A. Ash, Sudipta K. Shaw, Karamatullah Danyal, T. Chen, Dennis R. Dean, Lance C. Seefeldt, Kylie A. Vincent

Chemistry and Biochemistry Faculty Publications

We demonstrate electrochemical control of the nitrogenase MoFe protein, in the absence of Fe protein or ATP, using europium(III/II) polyaminocarboxylate complexes as electron transfer mediators. This allows the potential dependence of proton reduction and inhibitor (CO) binding to the active site FeMo-cofactor to be established. Reduction of protons to H2 is catalyzed by the wild type MoFe protein and Β-98Tyr→His and Β-99Phe→His variants of the MoFe protein at potentials more negative than -800 mV (vs. SHE), with greater electrocatalytic proton reduction rates observed for the variants compared to the wild type protein. Electrocatalytic proton reduction is strongly …


Assessment Of The Presence And Strength Of H-Bonds By Means Of Corrected Nmr, Steve Scheiner Oct 2016

Assessment Of The Presence And Strength Of H-Bonds By Means Of Corrected Nmr, Steve Scheiner

Chemistry and Biochemistry Faculty Publications

The downfield shift of the NMR signal of the bridging proton in a H-bond (HB) is composed of two elements. The formation of the HB causes charge transfer and polarization that lead to a deshielding. A second factor is the mere presence of the proton-accepting group, whose electron density and response to an external magnetic field induce effects at the position of the bridging proton, exclusive of any H-bonding phenomenon. This second positional shielding must be subtracted from the full observed shift in order to assess the deshielding of the proton caused purely by HB formation. This concept is applied …


Geolocator Tracking Of Great Reed-Warblers (Acrocephalus Arundinaceus) Identifies Key Regions For Migratory Wetland Specialists In The Middle East And Sub-Saharan East Africa, Joshua J. Horns, Evam Buechley, Mark William Chynoweth, Lale Aktay, Emrah Çoban, Mehmet Sli Kırpık, Jordan M. Herman, Yakup Şaşmaz, Çağan H. Şekercioğlu Oct 2016

Geolocator Tracking Of Great Reed-Warblers (Acrocephalus Arundinaceus) Identifies Key Regions For Migratory Wetland Specialists In The Middle East And Sub-Saharan East Africa, Joshua J. Horns, Evam Buechley, Mark William Chynoweth, Lale Aktay, Emrah Çoban, Mehmet Sli Kırpık, Jordan M. Herman, Yakup Şaşmaz, Çağan H. Şekercioğlu

Wildland Resources Faculty Publications

Wetland-dependent migratory songbirds represent one of the most vulnerable groups of birds on the planet, with >67% of wetland-obligate species threatened with extinction. One of the major hurdles for conservation efforts is determining the migration routes, stopover sites, and wintering sites of these species. We describe an annual migration cycle revealed by geolocator tracking of Great Reed-Warblers (Acrocephalus arundinaceus) breeding in the Aras River wetlands of eastern Turkey. Because of its relatively large size and breeding ground fidelity, the Great ReedWarbler is an excellent candidate for geolocator studies and can serve as an indicator species for other wetland songbirds, many …


Exploring The Potential Linkages Between Oil-Field Brine Reinjection, Crystalline Basement Permeability, And Triggered Seismicity For The Dagger Draw Oil Field, Southeastern New Mexico, Usa, Using Hydrologic Modeling, Y. Zhang, Stanislav S. Edel, Jeff D. Pepin, Mark A. Person, Ronald F. Broadhead, J. P. Ortiz, Susan L. Bilek, Peter S. Mozley, James P. Evans Oct 2016

Exploring The Potential Linkages Between Oil-Field Brine Reinjection, Crystalline Basement Permeability, And Triggered Seismicity For The Dagger Draw Oil Field, Southeastern New Mexico, Usa, Using Hydrologic Modeling, Y. Zhang, Stanislav S. Edel, Jeff D. Pepin, Mark A. Person, Ronald F. Broadhead, J. P. Ortiz, Susan L. Bilek, Peter S. Mozley, James P. Evans

Geosciences Faculty Publications

We used hydrologic models to explore the potential linkages between oil-field brine reinjection and increases in earthquake frequency (up to Md 3.26) in southeastern New Mexico and to assess different injection management scenarios aimed at reducing the risk of triggered seismicity. Our analysis focuses on saline water reinjection into the basal Ellenburger Group beneath the Dagger Draw Oil field, Permian Basin. Increased seismic frequency (>Md 2) began in 2001, 5 years after peak injection, at an average depth of 11 km within the basement 15 km to the west of the reinjection wells. We considered several scenarios …


Plasma Deflection Test Setup For E-Sail Propulsion Concept, Allen Andersen, Jason Vaughn, Todd Schneider, Ken Wright Oct 2016

Plasma Deflection Test Setup For E-Sail Propulsion Concept, Allen Andersen, Jason Vaughn, Todd Schneider, Ken Wright

Presentations

The Electronic Sail or E-Sail is a novel propulsion concept based on momentum exchange between fast solar wind protons and the plasma sheath of long positively charged conductors comprising the E-Sail. The effective sail area increases with decreasing plasma density allowing an E-Sail craft to continue to accelerate at predicted ranges well beyond the capabilities of existing electronic or chemical propulsion spacecraft. While negatively charged conductors in plasmas have been extensively studied and flown, the interaction between plasma and a positively charged conductor is not well studied. We present a plasma deflection test method using a differential ion flux probe …


Space Environment Effects Of Ionizing Radiation On Seed Germination And Growth, Alex Souvall, Takuyuki Sakai, Takahiro Shimizu, Yuta Takahashi, Midori Morikawa, Shusuke Okita, Akihiro Nagata, Toshihiro Kameda, Shaunda Wenger, Jr Dennison Oct 2016

Space Environment Effects Of Ionizing Radiation On Seed Germination And Growth, Alex Souvall, Takuyuki Sakai, Takahiro Shimizu, Yuta Takahashi, Midori Morikawa, Shusuke Okita, Akihiro Nagata, Toshihiro Kameda, Shaunda Wenger, Jr Dennison

Presentations

An initial limited set of tests of germination rate and seed growth in a controlled environment have identified statistically significant differences between control samples and seed flown in a Russian LEO research flight. Most significantly, average seed germination of space borne seeds was 2 days less than the 6 days for the control seeds. Modification of the seed coat leading to enhanced rate of water uptake, as a result of radiation from the space environment or abrasion due to launch vibrations, is hypothesized to cause early germination. High school students will conduct growth tests on seeds exposed to simulated space …


High Altitude Dependence Of Ionizing Radiation From Cosmic Rays, Zack Gibson, Akihiro Nagata, Midori Morikawa, Takuyuki Sakai, Takahiro Shimizu, Yuta Takahashi, Shusuke Okita, Raul Ramirez, Alexandra Hughlett, Toshihiro Kameda, Jr Dennison Oct 2016

High Altitude Dependence Of Ionizing Radiation From Cosmic Rays, Zack Gibson, Akihiro Nagata, Midori Morikawa, Takuyuki Sakai, Takahiro Shimizu, Yuta Takahashi, Shusuke Okita, Raul Ramirez, Alexandra Hughlett, Toshihiro Kameda, Jr Dennison

Posters

The flux of ionizing radiation from cosmic background sources has been measured as a function of altitude using a compact Geiger counter aboard a high altitude balloon. The payload was developed by researchers from University of Tsukuba and flown under the auspices of the Utah State Get-Away-Special (GAS) team. Dose rate, temperature, pressure, humidity, altitude and position data were acquired during a ~4 hour flight up to an altitude of 32 km in August 2016. The altitude reached by this balloon was more than 5 times the height of that reached by Victor Hess’ experiment in 1912, which later won …


Relaxation Of Radiation Effects On The Optical Transmission Of Polymers, Alexandra Hughlett, Tyler Kippen, J. R. Dennison Oct 2016

Relaxation Of Radiation Effects On The Optical Transmission Of Polymers, Alexandra Hughlett, Tyler Kippen, J. R. Dennison

Posters

Changes in optical transmission of polymers over time were studied to determine the factors contributing to relaxation of defect states induced by intense radiation doses. Samples of low density polyethylene (LDPE), polyether ether ketone (PEEK), polypropylene (PP), and polyimide (PI) received doses up to 500 MGy from an 8 MeV electron accelerator. These doses were intended to simulate long-term exposure of common spacecraft materials in geosynchronous orbit. Features and absorption edges in ~250 nm to 1000 nm UV to IR transmission spectra can be related to energies associated with various defects previously observed in these highly disordered materials. Recent work …


Highly Selective Halide Receptors Based Upon Chalcogen, Pnicogen, And Tetrel Bonds, Steve Scheiner Oct 2016

Highly Selective Halide Receptors Based Upon Chalcogen, Pnicogen, And Tetrel Bonds, Steve Scheiner

Chemistry and Biochemistry Faculty Publications

The interactions of halides with a number of bipodal receptors are examined via quantum chemical methods. The receptors are based upon a dithieno thiophene framework in which two S atoms can engage in a pair of chalcogen bonds with a halide. These two S atoms are replaced by P and As atoms to compare chalcogen with pnicogen bonding, and by Ge which engages in tetrel bonds with the receptor. Zero, one, and two O atoms are added to the thiophene S atom which is not directly involved in the interaction with the halides. Fluoride is bound the most strongly, followed …


Temperature Dependence Of Electrostatic Breakdown In Highly Disordered Polymers, Tyler Kippen Oct 2016

Temperature Dependence Of Electrostatic Breakdown In Highly Disordered Polymers, Tyler Kippen

Senior Theses and Projects

No abstract provided.


Sensitivity Of Seven Diverse Species To Blue And Green Light: Interactions With Photon Flux, Michael Chase Snowden, Bruce Bugbee, Kevin R. Cope Oct 2016

Sensitivity Of Seven Diverse Species To Blue And Green Light: Interactions With Photon Flux, Michael Chase Snowden, Bruce Bugbee, Kevin R. Cope

Plants, Soils, and Climate Faculty Publications

Despite decades of research, the effects of spectral quality on plant growth, and development are not well understood. Much of our current understanding comes from studies with daily integrated light levels that are less than 10% of summer sunlight thus making it difficult to characterize interactions between light quality and quantity. Several studies have reported that growth is increased under fluorescent lamps compared to mixtures of wavelengths from LEDs. Conclusions regarding the effect of green light fraction range from detrimental to beneficial. Here we report the effects of eight blue and green light fractions at two photosynthetic photon fluxes (PPF; …


The Persistence And Characteristics Of Chinook Salmon Migrations To The Upper Klamath River Prior To Exclusion By Dams, John B. Hamilton, Dennis W. Rondorf, William R. Tinniswood, Ryan J. Leary, Tim Mayer, Charleen Gavette, Lynne A. Casal Oct 2016

The Persistence And Characteristics Of Chinook Salmon Migrations To The Upper Klamath River Prior To Exclusion By Dams, John B. Hamilton, Dennis W. Rondorf, William R. Tinniswood, Ryan J. Leary, Tim Mayer, Charleen Gavette, Lynne A. Casal

Wildland Resources Faculty Publications

In this research article, John Hamilton and his co-authors present extensive new research and information gathered since a 2005 publication on the historical evidence of anadromomous fish distribution in the Upper Klamath River watershed. Using historical accounts from early explorers and ethnographers to early-twentieth-century photographs, newspaper accounts, and government reports, the authors provide a more complete record of past salmon migrations. The updated record “substantiate[s] the historical persistence of salmon, their migration characteristics, and the broad population baseline that will be key to future commercial, recreational, and Tribal fisheries in the Klamath River and beyond.” During a time when salmon …