Physical Sciences and Mathematics Commons^™

Gas Production Kinetics And In Vitro Degradability Of Tannin-Containing Legumes, Alfalfa And Their Mixtures., Sebastian Lagrange, S. Lobón, Juan J. Villalba

Wildland Resources Student Research

The aim of this study was to determine in vitro ruminal degradability and gas production kinetics of sainfoin (Onobrichis viciifolia; SF), birdsfoot trefoil (Lotus corniculatus; BFT), alfalfa (Medicago sativa L.; ALF) and their binary or trinary mixtures using the gas production technique. The proportions in the mixtures represented: (1) those selected by lambs in a free-choice experiment (70:30 and 50:35:15 ratios for binary and trinary combinations, respectively), or (2) equal proportions (50:50 or 33:33:33 ratios for binary or trinary mixtures, respectively). Organic matter digestibility was greater in ALF and BFT than in SF (0.791 and 0.796 vs …

Climatization-Negligent Attribution Of Great Salt Lake Desiccation: A Comment On Meng (2019), Michael L. Wine, Sarah E. Null, R. Justin Derose, Wayne A. Wurtsbaugh

Wildland Resources Faculty Publications

A recent article reviewed data on Great Salt Lake (Utah) and concluded falsely that climate changes, especially local warming and extreme precipitation events, are primarily responsible for lake elevation changes. Indeed climatically influenced variation of net inflows contribute to huge swings in the elevation of Great Salt Lake (GSL) and other endorheic lakes. Although droughts and wet cycles have caused lake elevation changes of over 4.5 m, they have not caused a significant long-term change in the GSL stage. This recent article also suggests that a 1.4 °C rise in air temperature and concomitant increase in the lake's evaporative loss …

Influence Of Vibrationally-Induced Structural Changes On Carbon Nanotube Forests Suppression Of Electron Yield, Jordan Lee, Brian Wood, Gregory Wilson, T.-C. Shen, Jr Dennison

Conference Proceedings

Carbon nanotube (CNT) forest coatings have been found to lower electron yield from material surfaces. The suppressed yields have been attributed to both the lower inherent yields of low-atomic number carbon and the enhanced electron recapture resulting from the morphology of the carbon layer. To explore the relative contributions of these two causes of yield suppression, tests have been made on CNT forest-coated conducting substrate samples subjected to vibrationally-induced changes of the coating structure. The extent of vibrationally-induced structural changes—due, for example, to shear-force conditions during space-vehicle transit—are of interest, as CNT have been a frequent topic of scientific curiosity …

On The Ability Of Pnicogen Atoms To Engage In Both Σ And Π-Hole Complexes. Heterodimers Of Zf2C6H5 (Z = P, As, Sb, Bi) And Nh3, Wiktor Zierkiewicz, Mariusz Michalczyk, Rafał Wysokiński, Steve Scheiner

Chemistry and Biochemistry Faculty Publications

When bound to a pair of F atoms and a phenyl ring, a pyramidal pnicogen (Z) atom can form a pnicogen bond wherein an NH₃ base lies opposite one F atom. In addition to this σ-hole complex, the ZF₂C₆H₅ molecule can distort in such a way that the NH₃ approaches on the opposite side to the lone pair on Z, where there is a so-called π-hole. The interaction energies of these π-hole dimers are roughly 30 kcal/mol, much larger than the equivalent quantities for the σ-hole complexes, which are only 4–13 kcal/mol. On …

First Ground‐Based Conjugate Observations Of Stable Auroral Red (Sar) Arcs, C. Martinis, J. Baumgardner, M. Mendillo, Michael J. Taylor, T. Moffat-Griffin, J. Wroten, C. Sullivan, R. Macinnis, B. Alford, Y. Nishimura

All Physics Faculty Publications

During the geomagnetic storm of 1 June 2013, all‐sky imagers located at geomagnetically conjugate locations at Millstone Hill, USA (42.6°N, 71.4°W, 50.9° mag lat) and at Rothera, Antarctica (67.5°S, 68.1°W, ‐53.2° mag lat), allowed us to measure a stable auroral red (SAR) arc simultaneously in both hemispheres for the first time. The arc measured in one hemisphere was observed very close to its conjugate location in the opposite hemisphere. While spatial characteristics, such as equatorward motion and latitudinal extent, were similar at both sites, morphological properties, for example, arc brightness and shape of the poleward edges, differed. The overall brightness …

Structures Of Clusters Surrounding Ions Stabilized By Hydrogen, Halogen, Chalcogen, And Pnicogen Bonds, Steve Scheiner, Mariusz Michalczyk, Wiktor Zierkiewicz

Chemistry and Biochemistry Faculty Publications

Four H-binding HCl and HF molecules position themselves at the vertices of a tetrahedron when surrounding a central Cl-. Halogen bonding BrF and ClF form a slightly distorted tetrahedron, a tendency that is amplified for ClCN which forms a trigonal pyramid. Chalcogen bonding SF2, SeF2, SeFMe, and SeCSe occupy one hemisphere of the central ion, leaving the other hemisphere empty. This pattern is repeated for pnicogen bonding PF3, SeF3 and AsCF. The clustering of solvent molecules on one side of the Cl- is attributed to weak attractive interactions between them, including chalcogen, pnicogen, halogen, and hydrogen bonds. Binding energies of …

On The Relationship Between North India Summer Monsoon Rainfall And East Equatorial Indian Ocean Warming, Ramesh Kumar Yadav, Mathew Koll Roxy

Plants, Soils and Climate Student Research

Generally, a strong north India summer-monsoon rainfall (NISR) is associated with anomalous upper troposphere ridge over northwest of India. This ridge triggers anomalous northerly winds over Tibetan Plateau and easterlies over India. The easterly anomaly over India reduces the tropospheric wind shear, while the northerly at Tibetan plateau allows frequent intrusions of high-latitude dry and cold meridional winds to interact with the lower-level relatively warm and moist easterly monsoonal flow, enhancing the NISR. The current study, using a suite of observations, reanalysis products and numerical model sensitivity experiments, explores the changes in NISR, and its association with the warming in …

Predictive Distributions Via Filtered Historical Simulation For Financial Risk Management, Tyson Clark

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

Filtered historical simulation with an underlying GARCH process can be used as a valuable tool in VaR analysis, as it derives risk estimates that are sensitive to the distributional properties of the historical data of the produced predictive density. I examine the applications to risk analysis that filtered historical simulation can provide, as well as an interpretation of the predictive density as a poor man’s Bayesian posterior distribution. The predictive density allows us to make associated probabilistic statements regarding the results for VaR analysis, giving greater measurement of risk and the ability to maintain the optimal level of risk per …

Feasibility Of Multi-Year Forecast For The Colorado River Water Supply: Time Series Modeling, Brian Plucinski

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

The Colorado River is one of the largest resources for water in the United States, as well as being an important asset to the economy. Previous studies have shown a connection between the Great Salt Lake and the Colorado River. This study used time series analysis to build models to predict the water supply of the Colorado River ten years out. These models used data from the Colorado River in addition to Great Salt Lake water elevation. Several models suggest a decline in water supply from 2013 – 2020, before starting to increase. These predictions differ from predictions published by …

Octonionic Maxwell Equations, Ben Shaw

Physics Capstone Projects

An introduction to Quaternions and Octonions is given, and the Maxwell Equations are formulated in terms of each. The conventional, source-free relativistic theory of eight dimensional electromagnetism is introduced and examined. Similarly, the source-free Octonionic Maxwell Equations are developed, and it is shown that the seven dimensional electric and magnetic fields–pure Octonions–each admit plane wave solutions. An Octonionic Faraday tensor is constructed and compared with the conventional Faraday tensor, and it is shown that, in the source-free case, the conventional and Octonionic theories are equivalent.

The Effects Of Beta Radiation On The Electrostatic Discharge Of Ldpe, Kip Quilter

Physics Capstone Projects

Spacecraft charging is one of the leading causes of space environment induced anomalies [1]. Spacecraft charging occurs when an electric charge builds up on a spacecraft; one way for the charge to accumulate is from natural space plasma [1]. The charge can lead to many different problems, including electrostatic discharge (ESD). Insulating materials such as highly disordered polymers do not allow charge to move freely; this can result in areas of localized charge to build up creating differing electric potentials [2]. Once the difference in potentials is great enough, electrostatic discharge occurs causing irreversible damages to the insulating polymers.

ESD …

River Hydrology, Morphology, And Dynamics In An Intensively Managed, Transient Landscape, Sara Ann Kelly

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Rivers create beautiful patterns and provide drinking water to millions. However an alarming number of rivers in the US and globally are threatened by excess sediment and nutrients. Agricultural rivers draining erodible soils are particularly vulnerable. Rivers of southern Minnesota provide a unique opportunity to study water and sediment dynamics in a naturally vulnerable system. Sediment reduction strategies are needed to ensure biological integrity and adequate water quality. Here, I address the questions: 1) have climate, land use practices, or both affected streamflows in Midwest agricultural rivers?, 2) which streamflows set the rate of river bluff erosion?, and 3) how …

Assessing Paleoenvironmental And Geomorphic Variability In Relationship To Paleoindian Site Burial; Centennial Valley, Montana, Hillary A. Jones

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Wave action along the shores of Lima Reservoir in Centennial Valley, Montana is actively eroding the southern margins of three neighboring Paleoindian sites. Despite ostensible similarity among the sites, major site formation differences are apparent in exposed sediments. Shoreline cutbank exposures one-to-five meters high connect the sites and reveal a complicated geomorphic history. Although each site contains artifact evidence of terminal Pleistocene-early Holocene occupations, Paleoindian components at these three localities occur in very different contexts: one is buried, while the other two are apparent surface scatters. This raise the question of why sites of the same age are in both …

Methods For Meta–Analyses Of Rare Events, Sparse Data, And Heterogeneity, Brinley Zabriskie

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The vast and complex wealth of information available to researchers often leads to a systematic review, which involves a detailed and comprehensive plan and search strategy with the goal of identifying, appraising, and synthesizing all relevant studies on a particular topic. A meta–analysis, conducted ideally as part of a comprehensive systematic review, statistically synthesizes evidence from multiple independent studies to produce one overall conclusion. The increasingly widespread use of meta–analysis has led to growing interest in meta–analytic methods for rare events and sparse data. Conventional approaches tend to perform very poorly in such settings. Recent work in this area has …

Phosphorus Rate Effects With And Without Avail® On Dryland Winter Wheat In An Eroded Calcareous Soil, Ryan C. Hodges

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Soluble phosphorus fertilizer is bound in the soil rapidly after application in soils high in calcium. A fertilizer additive known as AVAIL® (J.R. Simplot Company) is purported to keep applied phosphorus fertilizer more available to plants by binding to soil minerals such as calcium, magnesium, and iron, thereby reducing phosphorus binding. This could prove useful due to the attraction of AVAIL® with cations such as Ca²⁺, but is fairly unstudied for dryland wheat production on alkaline, calcium-rich soils. The objective of this study is to evaluate the effect of low-rate fertilizer treatments with AVAIL® on dryland small grain …

Analysis Of Small Faults In A Sandstone Reservoir Analog, San Rafael Desert: Implications For Fluid Flow At The Reservoir-Scale, Leslie Noël Clayton

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

We examined small-displacement faults in the Jurassic Entrada Sandstone adjacent to the Iron Wash Fault, central Utah east of the San Rafael Swell, in order to describe the nature and timing of past fluid movement and deformation in the Entrada Sandstone. Using field studies, microscopy, and X-ray diffraction analysis, we identified mineralized fractures and cementation features in association with deformation bands and fractures at the interface of the Earthy and Slick Rock Members of the Entrada Sandstone.

Where the faults cross the Earthy-Slick Rock Member interface, deformation band faults in the Slick Rock Member become opening-mode fractures in the Earthy …

Elevating Outdoor Recreation Together: Opportunities For Collaboration Between State Offices Of Outdoor Recreation And Federal Land Management Agencies, Brooke A. Sausser

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Outdoor recreation is a robust pillar of local, state, and national economies as well as a critical component of residents’ quality of life. Recognition of the economic power of the outdoor industry, fused with the growing desire for greater outdoor recreation opportunities, has inspired more than 11 states to establish state offices of outdoor recreation. The organizational structure and mission of each office is tailored to each state, varying from temporary task forces, councils, and commissions to more permanent offices or advisory positions. These offices, though embedded within various sectors of state government, often coordinate across or blend the functions …

Mountain-Block Recharge To The Cache Valley Principal Aquifer And Geochemical Controls On Groundwater Movement In Alpine Karst, Skyler J. Sorsby

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Groundwater is documented to flow through solution-widened fractures and bedding planes in limestone and dolostone units in low-relief topography. This enhancement, or karstification, is much harder to study in alpine environments like the Bear River Range of northern Utah. This is problematic, due to the fact that the Bear River Range karst aquifer system supplies the City of Logan with a large quantity of water at Dewitt Spring. Furthermore, the karst aquifer sustains the Logan River for much of the year, and may allow groundwater to flow directly in the subsurface to the Cache Valley principal aquifer system.

Flow measurements …

Spring Precipitation In Intermountain West Influenced By Quasi-Biennial Oscillation, Jason A. Phelps

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Unusually wet spring seasons in the Intermountain West (IW) have been linked to a wind fluctuation in higher levels of the atmosphere near the equator. Strong westerly winds during October-January often result in unusually wet conditions in the following spring. Average winds near the equator at 75,000 feet above the earth’s surface can be split into different categories according to wind direction: westerly (positive), easterly (negative), and transitional. Composites of winter and spring precipitation anomalies based on these different categories show that strong westerly winds occur in October-January prior to most extreme spring precipitation events. Drier springs tend to occur …

An Examination Of Seasonal Shifts In Climate And Visitation, And Perspectives On Seasonal Shifts And Climate Adaptation Strategies In Tourism And Recreation Businesses For Moab, Utah, Elizabeth Cook

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The city of Moab, an outdoor recreation hub in eastern Utah, has been encountering both shifts in the seasonality of visitation, and increases in tourist visitation, even with summer temperatures above the normal high. Tourism research describing the effects of climate change on the outdoor recreation industry has focused on winter, snow-dependent activities, while studies in Moab city have focused on the economic value of outdoor recreational activities. Few studies have described the relationship between seasonal tourism and climate change for arid desert locations. The purpose of this study is to describe how the tourism and recreation industry in Moab, …

Micro- To Macro-Scale Structural And Lithological Architecture Of Basal Nonconformities: Implications For Fluid Flow And Injection Induced Seismicity, Garth Hesseltine

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Rising incidents of earthquakes caused by human activity in the United States, known as induced earthquakes, is a growing concern. Induced earthquakes may occur when fluid and/or wastewater is injected several kilometers beneath the Earth’s surface into sedimentary rocks. Fluids and pressures can migrate from the sedimentary rocks, which are typically friendlier to fluid flow, into underlying less friendlier crystalline rocks along fluid pathways weakening and possibly reactivating preexisting faults. Understanding potential fluid pathways and/or barriers from the sedimentary rocks to crystalline rocks is crucial. I investigate the structure, composition, and heterogeneity of rocks near the contact between the sedimentary …

Visible Light-Triggered Carbon Monoxide-Releasing Molecules, Marina Popova

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Carbon monoxide (CO) is now well established as one of the signaling molecules in higher organisms, including humans. Due to its physiological roles, CO is now accepted as a potential therapeutic agent. The use of CO gas has been studied in multiple clinical trials. Vasodilation, anti-inflammatory, anti-apoptotic, anti-proliferative and cytoprotective effects are just a few of the pharmacological actions attributed to CO gas in various models of diseases. Use of inhaled CO gas as a therapeutic has many limitations which necessitate the development of a new approach for CO delivery. In order to handle CO safely, compounds that release CO …

Juxtaposition At 45 Km Of Temperatures From Rayleigh-Scatter Lidar And Reanalysis Models, David K. Moser

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Weather and climate forecasts are almost exclusively produced by computer models, which use atmospheric measurements as starting points. It is a well-known and joked-about fact that model predictions can be incorrect at times. One of the reasons this happens is due to gaps in our knowledge of atmospheric conditions in areas where measurements don’t often taken place, such as the mesosphere, which stretches from roughly 45-90 km altitude.

A lidar is a device that can shoot out short bursts of laser light to measure things such as atmospheric thickness at a distance. From this information one can then derive the …

Ediacaran Depositional Age And Subsequent Fluid-Rock Interactions In The Mutual And Browns Hole Formations Of Northern Utah, Ashley W. Provow

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Constraining the depositional age of Neoproterozoic stratigraphy in western North America has implications for correlating global glaciation and tectonic events. The depositional ages of the Neoproterozoic Mutual and Browns Hole formations of northern Utah are controlled by two conflicting datapoints. However, new U-Pb geochronological data from 95 detrital apatite grains refines the maximum depositional age of the volcanic member of the Browns Hole Formation to 613 ± 12 Ma (2σ). This places new restrictions on the time available for the deposition of underlying units. Due to debate regarding the age models for underlying stratigraphy, two scenarios for sediment accumulation rates …

Structural Control Of Thermal Fluid Circulation And Geochemistry In A Flat-Slab Subduction Zone, Peru, Brandt E. Scott

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Hot spring geochemistry from the Peruvian Andes provide insight on how faults, or fractures in the Earth's crust, are capable of influencing fluid circulation. Faults can either promote or inhibit fluid flow and the goal of this study is test the role of a major fault, such as the Cordillera Blanca detachment, as a channel for transporting deep fluids to the surface. Hot springs are abundant in the Cordillera Blanca and Huayhuash ranges in Peru, and several springs issue along the Cordillera Blanca detachment, making this region an ideal setting for our study. To test the role of the Cordillera …

Formation Of Radial Patterns Via Mixed Attractive And Repulsive Interactions For Schrödinger Systems, Jaeyoung Byeon, Youngae Lee, Zhi-Qiang Wang

Mathematics and Statistics Faculty Publications

This paper is concerned with the asymptotic behavior of least energy vector solutions for nonlinear Schrödinger systems with mixed couplings of attractive and repulsive forces. We focus here on the radially symmetric case while the general studies were already conducted in our earlier work [J. Byeon, Y. Sato, and Z.-Q. Wang, J. Math. Pures Appl. (9), 106 (2016), pp. 477--511], [J. Byeon, Y. Sato, and Z.-Q. Wang, J. Fixed Point Theory Appl., 19 (2017), pp. 559--583]. Though there is still the general phenomenon of component-wise pattern formation with co-existence of partial synchronization and segregation for positive least energy …

Influence Of Monomer Deformation On The Competition Between Two Types Of Σ-Holes In Tetrel Bonds, Rafal Wysokiński, Mariusz Michalczyk, Wiktor Zierkiewicz, Steve Scheiner

Chemistry and Biochemistry Faculty Publications

One of several tetrel (T) atoms was covalently attached to three F atoms and a substituted phenyl ring. A NH3 base can form a tetrel bond with TF3C6H2R3(T = Si, Ge, Sn, Pb; R = H, F, CH3) in a position opposite either an F atom or the ring. The σ-hole opposite the highly electron-withdrawing F (T-F) is more intense than that opposite the ring (T-C). However, when the Lewis base deforms from a tetrahedral to a trigonal bipyramidal shape so as to accommodate the base, it is the T-C σ-hole that is more intense. Accordingly, it is the T-C …

The International Community Coordinated Modeling Center Space Weather Modeling Capabilities Assessment: Overview Of Ionosphere/Thermosphere Activities, Ludger Scherliess, I. Tsagouri, E. Yizengaw, S. Bruinsma, J. S. Shim, A. Coster, J. M. Retterer

All Physics Faculty Publications

The Earth's ionosphere/thermosphere (I/T) system exhibits complicated weather variability that can have adverse effects on human operations and systems, and consequently, there is a need for both accurate and reliable specifications and forecasts for this region. As part of the international effort to evaluate and assess the predictive capabilities of space weather models, four working groups for the I/T system have been created with the goal to devise a concerted model validation effort for the I/T environment. This paper presents an overview of the team efforts and reports on the progress made. As a first step, the working teams have …

Multiple Local Σ-Aromaticity Of Nonagermanide Clusters, Nikolay V. Tkachenko, Alexander I. Boldyrev

Chemistry and Biochemistry Faculty Publications

Nonagermanide clusters are widely used in inorganic synthesis and are actively studied by experimentalists and theoreticians. However, chemical bonding of such versatile species is still not completely understood. In our work we deciphered a bonding pattern for various experimentally obtained nonagermanide species. We localized the electron density via the AdNDP algorithm for the model structures ([Ge₉]⁴⁻, [Ge₉{P(NH₂)₂}₃]⁻, Cu[Ge₉{P(NH₂)₂}₃] and Cu(NHC)[Ge₉{P(NH₂)₂}₃]) and obtained a simple and chemically intuitive bonding pattern which …

General Relativity As A Biconformal Gauge Theory, James Thomas Wheeler

All Physics Faculty Publications

We consider the conformal group of a space of dim n=p+q, with SO(p,q) metric. The quotient of this group by its homogeneous Weyl subgroup gives a principal fiber bundle with 2n-dim base manifold and Weyl fibers. The Cartan generalization to a curved 2n-dim geometry admits an action functional linear in the curvatures. Because symmetry is maintained between the translations and the special conformal transformations in the construction, these spaces are called biconformal; this same symmetry gives biconformal spaces overlapping structures with double field theories, including manifest T-duality. We establish that biconformal geometry is …