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Comparison Of Private And Public Lab Fertilizer Recommendation Impacts On Field Crop Production And Soil Test Results, Megan Baker May 2024

Comparison Of Private And Public Lab Fertilizer Recommendation Impacts On Field Crop Production And Soil Test Results, Megan Baker

All Graduate Theses and Dissertations, Fall 2023 to Present

There are many sources that farmers utilize to determine fertilizer needs for crops such as private and public labs, crop advisors, and fertilizer dealers. In many cases, these sources provide recommendations for a specific crop that can vary greatly, which can lead to large differences in cost. An experiment was established in 2021 with 12 sites across the state of Utah in alfalfa, small grains, and corn to test and compare fertilizer recommendations from five labs. The recommendations tested were from two public labs (Utah State University and the University of Idaho) and three commercial labs located in the Western …


4r Nitrogen And Water Optimization Combinations For Intermountain West Field Crops, Tina Sullivan May 2022

4r Nitrogen And Water Optimization Combinations For Intermountain West Field Crops, Tina Sullivan

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The concept of 4R (right source, rate, placement, and timing) management needs little introduction due to the surplus of nutrient studies in the literature for most cultivated crops. However, few studies have looked at these practices in the Intermountain West with nitrogen use, and fewer looked at 4R irrigation management. A survey was conducted to explore the interactions of nitrogen and irrigation management, test sensitivity to supply and price changes of nitrogen and irrigation for Utah and Idaho growers of small grains, corn, and potatoes, and determine the current adoption of precision agriculture options and identify the opportunities to improve. …


Nutrient Uptake And Water Quality In Great Salt Lake Wetland Impoundments, Rachel L. Buck May 2022

Nutrient Uptake And Water Quality In Great Salt Lake Wetland Impoundments, Rachel L. Buck

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Great Salt Lake (GSL) is the largest inland body of water on the Pacific flyway, a major pathway for migratory birds in the Americas that extends from Alaska to Patagonia. The lake is surrounded by approximately 360,000 acres of wetlands, providing critical food, shelter, cover, nesting areas, and protection to between 4–6 million birds that visit each year. Impounded wetlands were created as part of the GSL ecosystem to support waterfowl habitat. These large, shallow, submergent wetlands are diked to control water levels to sustain aquatic plants which are an important food source. Besides providing critical habitat, these impoundments …


Assessing The Role Of Magnetite In Municipal Wastewater Treatment, Patricia Ayaa May 2022

Assessing The Role Of Magnetite In Municipal Wastewater Treatment, Patricia Ayaa

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Some municipal wastewater treatment (MWWT) facilities have adopted magnetite in their treatment processes through a technology called BioMag® to meet effluent regulatory requirements for total nitrogen and total phosphorus. However, there is limited information on the mechanisms and efficiency of magnetite in the removal of nitrogen (N) and phosphorus (P) from wastewater. This research, therefore, estimated its effectiveness in the removal of these nutrients, with a case study of the Marlay-Taylor Water Reclamation Facility in Maryland. The intervention analysis model was used, but a new forecasting approach to the model was proposed to fit the data in this study and …


Climate-Driven Impacts Of Warming And Grazing On Sub-Arctic Coastal Wetlands In Alaska, Ryan T. Choi Aug 2021

Climate-Driven Impacts Of Warming And Grazing On Sub-Arctic Coastal Wetlands In Alaska, Ryan T. Choi

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Climate change is rapidly warming the Arctic, especially at lower latitudes. Warmer temperatures and earlier springs are altering the timing of plants and animals, especially for long-distance migratory herbivores. Changes in the timing of both plants and herbivores have the potential to impact plant productivity and nutrient cycling, while also altering plant community diversity and composition.

In chapter 2, I conducted a field experiment to investigate how earlier growing seasons and differences in arrival times of migratory geese influence physical traits of sedge forage species. I found that both an earlier growing season and late grazing by geese had similar …


The Fate And Cycling Of Nitrogen, Phosphorous, And Trace Heavy Metals In Beaver-Altered Headwater Streams, Desneiges S. Murray May 2021

The Fate And Cycling Of Nitrogen, Phosphorous, And Trace Heavy Metals In Beaver-Altered Headwater Streams, Desneiges S. Murray

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Human land-use can increase the amount of non-point source (NPS) pollution in a stream, negatively affecting ecosystem health and beneficial services provided by an ecosystem. Unfortunately, NPS pollution remains high in many waterbodies. Beaver dams may be a passive, cost-effective strategy for removing NPS pollution in headwater streams because beaver dams slow stream flow and collect sediments. Impounded sediments can change how nutrients and pollutants are cycled in a stream through multiple pathways. In the first part of our study, we investigated whether beaver activity can reduce nitrogen, phosphorous and heavy metals from otherwise traveling downstream. Results suggest beaver ponds …


Investigations Of Substrate Reduction By Nitrogenase: Light Powered Substrate Reduction By A Cds:Femoco System And Understanding Dinitrogen Inhibition Of Electron Transfer, Hayden Kallas May 2021

Investigations Of Substrate Reduction By Nitrogenase: Light Powered Substrate Reduction By A Cds:Femoco System And Understanding Dinitrogen Inhibition Of Electron Transfer, Hayden Kallas

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Nitrogen fixation is a key step of the nitrogen cycle which makes biologically inert N2 gas available for organisms to use in the form of ammonia. Nitrogen fixing microorganisms all contain the same enzyme called nitrogenase which catalyzes the six electron transfers to N2 required for conversion into ammonia. Nitrogenase is a two-component enzyme that contains a cofactor composed of iron and sulfur as well as heavier metals whose identity can be molybdenum, vanadium, or an additional iron atom depending on the variant. The two components of nitrogenase are the MFe protein and the Fe protein. The Fe …


Nitrogen Fertilizer Needs Of First-Year Small Grains Following Alfalfa, Collin Pound Aug 2020

Nitrogen Fertilizer Needs Of First-Year Small Grains Following Alfalfa, Collin Pound

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Wheat, barley, triticale, and oats, are small grains commonly grown as hay and grain following alfalfa in Utah and the Intermountain West, especially during drought years as they require less irrigation than corn. Several studies in many parts of the world have shown that first-year corn following alfalfa rarely needs nitrogen (N) fertilizer, yet relatively few have evaluated the N needs of small grains, especially small grains grown for hay. Objectives of this research were to determine whether N fertilizer is needed to economically optimize the yield and quality of first-year small grains following alfalfa, develop N guidelines, and whether …


Effect Of Plant Derived Tannins On Nitrogen And Carbon Cycling In Pasture Soils, Kathryn A. Slebodnik Aug 2020

Effect Of Plant Derived Tannins On Nitrogen And Carbon Cycling In Pasture Soils, Kathryn A. Slebodnik

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Pasture-finished beef has become increasingly popular, but nitrogen losses from these pastures are of concern. Legumes containing condensed tannins such as birdsfoot trefoil (Lotus corniculatus) and sainfoin (Onobrychis viciifolia) may serve as environmentally and economically viable alternative forages in pasture finishing systems while reducing soil nitrogen loss. The goal of this project was to understand how tannin type and concentration affects soil nitrogen cycling both in the lab and the field. This thesis: 1) compared the physical, chemical, and biological characteristics of soil samples obtained from grazed grass and tannin and non-tannin containing legume pastures, 2) …


Enhancing The Production And Sustainability Of Pasture-Fed Beef Using Non-Traditional Legume Forages, Andrea I. Bolletta Aug 2020

Enhancing The Production And Sustainability Of Pasture-Fed Beef Using Non-Traditional Legume Forages, Andrea I. Bolletta

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Despite the increasing worldwide demand for beef as a protein source, consumers are concerned about the sustainability of ruminant production systems. Their main concerns are animal welfare for feedlot-fed animals, greenhouse gas (GHG) emissions, global warming and worker safety. Traditional feedlot-based beef production systems have been associated with locally greater levels of soil, water and air contamination, as well as the overuse of antibiotics and growth hormones. The use of legume pastures such as cicer milkvetch (CMV) and birdsfoot trefoil (BFT), which fix their own nitrogen (N) and often contain beneficial secondary compounds such as tannins and provide for rapid …


Observation Of Struvite In The Mixed Microalgae Biofilm Matrix Of A Rotating Algal Biofilm Reactor During Nutrient Removal From Municipal Anaerobic Digester Filtrate, Kyle M. Hillman May 2020

Observation Of Struvite In The Mixed Microalgae Biofilm Matrix Of A Rotating Algal Biofilm Reactor During Nutrient Removal From Municipal Anaerobic Digester Filtrate, Kyle M. Hillman

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Central Valley Water Reclamation Facility (CVWRF) in Salt Lake City is the largest municipal wastewater treatment plant in Utah and must meet new and rigorous nutrient effluent standards–over 95% reduction in phosphorus output by 2025. Filtrate from CVWRF anaerobic digesters contains high levels of nitrogen, phosphorus, and magnesium. Supersaturation of these constituents leads to nuisance struvite precipitation that clogs belts, pumps, and pipes downstream of anaerobic digesters. Struvite is a mineral precipitate composed of equimolar magnesium, ammonium, and phosphate. Controlled precipitation of struvite helps prevent clogging and scaling, removes phosphate from wastewater, and generates a marketable fertilizer product.

Struvite was …


Measuring Nitrogen Transformation In Wastewater Impacted Streams Using In-Situ Benthic Chambers, Makenzi Beltran May 2019

Measuring Nitrogen Transformation In Wastewater Impacted Streams Using In-Situ Benthic Chambers, Makenzi Beltran

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Acrylic chambers and metal frames were installed at the sediment-water interface of streams impacted by the effluent from wastewater reclamation facilities in order to determine nitrogen rates for nitrification, denitrification, assimilation, ANAMMOX, and DNRA. Each chamber was dosed with an isotopic form of nitrate (15NO3-), and both isotopic (15N) and non-isotopic (14N) samples were collected. The project locations included East Canyon Creek near the East Canyon Wastewater Reclamation Facility in Park City, Utah and Box Elder Creek near the Brigham City Wastewater Treatment Plant in Brigham City, Utah. Separate chamber measurements …


Effect Of Tannin-Containing Legume Hays On Enteric Methane Emissions And Nitrogen Partitioning In Beef Cattle, Elizabeth K. Stewart Aug 2018

Effect Of Tannin-Containing Legume Hays On Enteric Methane Emissions And Nitrogen Partitioning In Beef Cattle, Elizabeth K. Stewart

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Cattle are responsible for greenhouse gas emissions such as carbon dioxide, methane and nitrous oxide. In particular, the cow-calf phase of production accounts for approximately 80 percent of the total beef production system greenhouse gas emissions. Tannins are chemical compounds found in certain forages and they have the potential to help reduce these negative environmental impacts. Thus, given that the cow-calf phase often relies on feeding hay, feeding tannin-containing hays may represent a significant mitigation practice.

With my MS program, I sought to explore whether tannin-containing hays fed to mother cows and heifers influence methane and nitrogen emissions relative to …


Nitrogen Availability And Use Efficiency In Corn Treated With Contrasting Nitrogen Sources, Avneet Kakkar Dec 2017

Nitrogen Availability And Use Efficiency In Corn Treated With Contrasting Nitrogen Sources, Avneet Kakkar

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The plant-soil nitrogen cycle plays a significant role in allocation of available N to plants, and improved understanding of N cycling helps sustainably increase fertilizer use efficiency. There are various processes (nitrogen mineralization and nitrification) involved in the availability and mobility of nitrogen in the soil. The primary objective of this study was to determine the NUE under contrasting nitrogen treatments over a period of five years. Additionally, we examined the effect of different N treatments on N mineralization and nitrification in conventional and organic farming systems.

This project was funded by Agriculture and Food Research Initiative Competitive Grants Program …


Forest Recovery, Nutrient Cycling And Carbon Sequestration In A Southern Appalachian Spruce-Fir Forest, Patrick T. Moore May 2013

Forest Recovery, Nutrient Cycling And Carbon Sequestration In A Southern Appalachian Spruce-Fir Forest, Patrick T. Moore

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Our forests provide us with a variety of services from clean water, forest products and wildlife habitat to the lesser known functions of nutrient cycling and carbon
sequestration. This research helps to demonstrate the extent of some of these services in a heavily disturbed southern Appalachian spruce-fir forest within Great Smoky Mountain National Park, the most heavily visited National Park in the United States. Following a catastrophic infestation of the non-native balsam wooly adelgid, the future of this forest was unknown, causing some to speculate about the future of this sensitive forest type. Though predictions about this forest’s future varied …


Assessment Of Atmospheric Nitrogen Deposition: Possible Effects On Alpine Ecosystems Above 9000 Feet In Grand Teton National Park, Jennifer Hansen May 2012

Assessment Of Atmospheric Nitrogen Deposition: Possible Effects On Alpine Ecosystems Above 9000 Feet In Grand Teton National Park, Jennifer Hansen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Certain forms of nitrogen (N) in the atmosphere are pollutants with effects that mimic fertilizer application. If there is too much N, it can become a stressor, and the ecosystem may undergo drastic changes (e.g. certain plant species may decline or disappear). The N load at which a system starts exhibiting negative effects is dependent on the type and location of the ecosystem. Alpine ecosystems (i.e. above 9000 feet in Wyoming) may be particularly sensitive to low levels of atmospheric N input because of short growing seasons, sparse plant cover, and shallow soils that limit their ability to absorb the …


Analysis Of The Import, Export, And Bioavailability Of Nitrogen And Phosphorus Within Pineview Reservoir, Brady K. Worwood Dec 2011

Analysis Of The Import, Export, And Bioavailability Of Nitrogen And Phosphorus Within Pineview Reservoir, Brady K. Worwood

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This study was conducted to provide new and useful data about Pineview Reservoir and its watershed, produce water and phosphorus (P) budgets for Pineview Reservoir, test the validity of conclusions made in the Pineview Reservoir Total Maximum Daily Loading (TMDL) document, and create estimates of nitrogen (N) loading to the reservoir from both surface and ground water sources. The production of the water and P budgets, as well as the N loading estimates, was accomplished by measuring flow, nitrate, ammonium, total phosphorus (TP), and soluble reactive phosphorus (SRP) that was entering and exiting the reservoir through surface water sources and …


Zeolite‐Based Algae Biofilm Rotating Photobioreactor For Algae And Biomass Production, Ashton M. Young Aug 2011

Zeolite‐Based Algae Biofilm Rotating Photobioreactor For Algae And Biomass Production, Ashton M. Young

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Alkaline conditions induced by algae growth in wastewater stabilization ponds create deprotonated ammonium ions that result in ammonia gas (NH3) volatilization. If algae are utilized to remediate wastewater through uptake of phosphorus, the resulting nitrogen loss will hinder this process because algae generally require a stoichiometric molar ratio of N16P1. Lower ratios of N/P due to loss of ammonia gas will limit the growth and yield of algae, and therefore will reduce phosphorus removal from the water phase into the algae phase. In order to reduce nitrogen loss through volatilization, an ammonium selective zeolite, …


15n Tracer And Modeling Analyses Of Nutrient Transport Through Lakes In A Subalpine Watershed, David M. Epstein May 2011

15n Tracer And Modeling Analyses Of Nutrient Transport Through Lakes In A Subalpine Watershed, David M. Epstein

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Lakes have historically been overlooked as important nutrient processors within their watersheds. In general ecologists have focused on streams as zones of uptake and transformation, while viewing lakes as simple nutrient traps. However, recent research has highlighted the large influence that lakes may have on water chemistry within their watersheds. Within the field of limnology, researchers have traditionally focused on the pelagic zone for in-lake production. Further research in shallow lakes has highlighted the role benthic production within the littoral zone plays in the lake ecosystem. The greater influence of lakes is highlighted when comparing watersheds containing lakes with watersheds …


Native Bunchgrass And Invasive Weed Establishment In Low Nutrient Rangeland Soils With Nitrogen And Phosphorus Manipulation, Jeffrey S. Burnham Dec 2010

Native Bunchgrass And Invasive Weed Establishment In Low Nutrient Rangeland Soils With Nitrogen And Phosphorus Manipulation, Jeffrey S. Burnham

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Competition between native perennial grasses and Bromus tectorum has been studied for many years. Recently, soil nutrients have been immobilized in an effort to preferentially inhibit growth of B. tectorum relative to native species. Most of this work has focused on soil N, but interactions with soil P are less studied and may be important as well. Additionally, although competitive effects and nutrient responses of several Centaurea spp. are well documented, data are lacking on the competitive effects that Centaurea virgata exerts on the establishment of native and exotic communities. A field experiment and a greenhouse experiment were conducted to …


An Investigation Of The Utilization Of Soil Water And Nitrogen Among Diverse Forage Plant Species And Mixtures, Sallee Reynolds Dec 2010

An Investigation Of The Utilization Of Soil Water And Nitrogen Among Diverse Forage Plant Species And Mixtures, Sallee Reynolds

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Species diversity achieved by adding novel functional groups (warm-season grasses and non-leguminous forbs) to pasture land, along with traditional grasses and legumes, could aid in the capture of nutrients and water in pasture systems by offering complementary rooting architecture to aid in water and nitrogen uptake and decrease nitrogen leaching. Because these species may differ from commonly used grasses and legumes in their seasonal pattern of productivity, they could also extend or enhance growing-season productivity. The goal of this project is to better understand the role of plant diversity in 1) nitrogen use and 2) distribution of rooting dynamics and …


Nitrogen Transport, Transformation And Cycling Through A Mountain Lake, Bull Trout Lake, Idaho, Usa, Ryan Settle Lockwood May 2009

Nitrogen Transport, Transformation And Cycling Through A Mountain Lake, Bull Trout Lake, Idaho, Usa, Ryan Settle Lockwood

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The effects of a mountain lake on nitrogen dynamics in a sub-alpine watershed were examined via watershed monitoring, mesocosm experiments, microcosm experiments, and enzymatic assays during spring and summer of a single year. Our study addressed the questions: (1) How does hydrologic transport through the lake affect the net fluxes of dissolved nitrogen (N) species? (2) What are the net effects of the littoral zone biota on dissolved N fluxes? (3) What are the seston and benthic uptake rates of nitrate? (4) What is the magnitude of N retention in littoral zone sediments? (5) What role does microbial hydrolysis of …


Nitrogen And Phosphorus Dynamics As Applied To Water Quality Under Management Intensive Grazing, Vaughn J. Thacker May 2009

Nitrogen And Phosphorus Dynamics As Applied To Water Quality Under Management Intensive Grazing, Vaughn J. Thacker

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Contamination of freshwater systems by nutrients has been studied extensively in the eastern U.S. Little research on the fate of nutrients in grazing conditions has been done in the western U.S. Western agriculture is often irrigated and research addressing the potential for leaching under these conditions is warranted. This study used Management Intensive Grazing (MIG) and eight grass-legume mixtures to evaluate the management and forage choice in relation to nitrogen and phosphorus leaching to ground water. Soil water samples were taken weekly through the growing season from 2001 through 2003. Water samples were analyzed for nitrate, ammonia, and phosphate. Soils …


Patch-Scale Effects Of An Invasive Ecosystem Engineer On The Structure And Function Of A Eutrophic Stream, Samuel J. Hochhalter May 2009

Patch-Scale Effects Of An Invasive Ecosystem Engineer On The Structure And Function Of A Eutrophic Stream, Samuel J. Hochhalter

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Recent theoretical and technological advances in ecosystem science have dramatically expanded the ways in which scientists can pursue and explore ecological questions. For my thesis research, I integrated the recent theoretical concept of organisms as ecosystem engineers with the relatively recent development of stable isotope tracer tests to ask the question: how does the invasive common carp affect stream ecosystem structure and function? To investigate the structuring role of carp, I measured autotroph seasonal distribution and abundance and macroinvertebrate seasonal abundance and diversity within two stream reaches in Spring Creek, Utah, USA; one with low carp biomass (LCB) and one …


The Role Of Brown Bears (Ursus Arctos) In Nutrient Transport Into Forests Near A Salmon Stream In Coastal British Columbia, Canada, Arthur Morris May 2002

The Role Of Brown Bears (Ursus Arctos) In Nutrient Transport Into Forests Near A Salmon Stream In Coastal British Columbia, Canada, Arthur Morris

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Nutrients from spawned salmon contribute to the fertility of rivers and riparian areas. Adjacent forests, even far from rivers, could receive substantial amounts of nitrogen and other nutrients from salmon. Since brown bears feed heavily on spawning salmon, bears probably influence the movement of nutrients from salmon into surrounding forests. Because salmon-derived nitrogen is high in 15N, increased isotopic enrichment is expected in forest soils and vegetation if this transport is occurring. Based on relative 15N enrichment of spawning areas, a quantitative estimate of marine-derived nitrogen (MDN) can be obtained using a linear two-source mixing model. To evaluate …


Synthesis And Protection Of Nitrogen Containing Heterocycles, Timothy I. Elwell May 1997

Synthesis And Protection Of Nitrogen Containing Heterocycles, Timothy I. Elwell

Undergraduate Honors Capstone Projects

The pyrrolo[2,3-d] pyrimidine ring systems are present in a variety of antibacterial/anticancer compounds. A scarcity of natural sources has made necessary the need for researchers to find more efficient methodologies to synthesize such compounds.1 The Edstrom research group is currently exploring new routes to these compounds, varying the protecting groups and the precursors used to make them.


A Slow-Release Nitrogen Fertilizer: Ammonium-Loaded Clinoptilolite, T. Scott Perrin May 1997

A Slow-Release Nitrogen Fertilizer: Ammonium-Loaded Clinoptilolite, T. Scott Perrin

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Crops grown in sandy soils require frequent irrigation. As a result, nitrogen (N) fertilizers. such as ammonium sulfate((NH4)2SO4), are leached from the rooting zone of crops. This loss of N increases N fertilizer use and the potential for nitrate (NO3-) contamination of water. Ammonium-loaded clinoptilolite (NH4+-Cp) may reduce this N leaching, increase N fertilizer use-efficiency, and prevent NO3- contamination of water while sustaining normal crop growth.

The potential of NH4+-Cp as a N fertilizer was assessed in three leaching experiments without plants and …


Asymmetric Adsorbate And Substrate Interactions In Physisorbed Systems: N2 On Graphite And Dipolar Molecules On Ionic Substrates, Teresa Ellen Burns Aug 1994

Asymmetric Adsorbate And Substrate Interactions In Physisorbed Systems: N2 On Graphite And Dipolar Molecules On Ionic Substrates, Teresa Ellen Burns

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Asymmetries in physisorbed systems give rise to interesting phases and phase transitions in two-dimensional (2D) monolayer and multilayer systems. The effects of asymmetric adsorbate and substrate interactions in monolayers of dipolar molecules on ionic substrates and N2 on graphite are studied.

In the case of dipolar molecules on ionic substrates, 2D dielectric phase transitions using a modified Blume-Emery-Griffiths (BEG) model are determined theoretically. A dipole adsorbed vertically above a metal ion lattice site, and pointing up (down), is assigned a spin S=+1 (S=-1). An empty lattice site is assigned a spin S=0. Analytic solutions for both ferroelectrically and antiferroelectrically …


Effects Of Methylene Chloride On Immune Function In Mice And The In Vitro Effect Of Methylene Chloride In Immunologic Assays, Man-Ping Wang May 1989

Effects Of Methylene Chloride On Immune Function In Mice And The In Vitro Effect Of Methylene Chloride In Immunologic Assays, Man-Ping Wang

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A number of toxicities associated with methylene chloride have been found in both human subjects and mice. However, relatively few studies have probed immunotoxicities of methylene chloride. In order to examine possible immunotoxicities or immunomodulating effects of methylene chloride, several tests of cellular immune function were performed using both human in in vitro studies and a mouse model.

Body weights and specific organ weights of thymus, spleen, liver, and kidney were normal in CD-1 mice given various concentrations of methylenechloride. However, a significantly reduced mitogenic response to phytohemagglutinin (PHA} and reduced interleukin-2 (IL-2} production was found in these methylene-chloride-treated mice. …


Nitrogen And Energy Budgets Of Production Ewes On Summer Range In Southwestern Utah, John W. Halpop May 1988

Nitrogen And Energy Budgets Of Production Ewes On Summer Range In Southwestern Utah, John W. Halpop

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Nitrogen (N) and energy budgets for free-roaming ewes were quantified on mountain summer range in southwestern Utah in 1986 and 1987. Diet quality (%N), in vitro organic matter digestibility (IVOMD), and energy were estimated with the use of five esophageally fistulated ewes. Excretion rates of N and energy to feces and urine were measured by total collection from five nonfistualted ewes.

Total intake N(gN/(MBW*d-1) tracked intraseasonal changes of dietary N percent but was apparently buffered by fluctuations in dry matter intake. In each year, total urine N was closely related to dietary N concentration, r2=0.97 (1986) …