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Breast Cancer Classification Of Mammographic Masses Using Circularity Max Metric, A New Method, Tae Keun Heo Jan 2016

Breast Cancer Classification Of Mammographic Masses Using Circularity Max Metric, A New Method, Tae Keun Heo

Electronic Theses and Dissertations

Breast cancer classification can be divided into two categories. The first category is a benign tumor, and the other is a malignant tumor. The main purpose of breast cancer classification is to classify abnormalities into benign or malignant classes and thus help physicians with further analysis by minimizing potential errors that can be made by fatigued or inexperienced physicians. This paper proposes a new shape metric based on the area ratio of a circle to classify mammographic images into benign and malignant class. Support Vector Machine is used as a machine learning tool for training and classification purposes. The improved …

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Development And Characterization Of A Recombinant Orf Virus Vector Expressing The Spike Protein Of Porcine Epidemic Diarrhea Virus, Kyle Hain Jan 2016

Development And Characterization Of A Recombinant Orf Virus Vector Expressing The Spike Protein Of Porcine Epidemic Diarrhea Virus, Kyle Hain

Electronic Theses and Dissertations

Orf virus (ORFV), the type member of the genus Parapoxvirus of the family Poxviridae, causes orf or cutaneous pustular dermatitis in sheep and goats. ORFV is a ubiquitous virus capable of re-infecting its hosts multiple times over time. ORFV causes a non-systemic, self-limiting disease which is usually restricted to the skin surrounding the virus entry sites. ORFV has evolved several immunomodulatory proteins (IMPs) that evade and/or modulate host immune responses to infection and contribute to virus virulence and disease pathogenesis. Given biological properties and unique immunomodula tor y properties, ORFV has gained significant attention in recent years for its …

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The Effect Of Copper And Zinc Source On Pre-Weaning Performance Of Cows, Health And Performance Of Suckling Calves, And Post-Weaning Feedlot Performance, Carcass Composition, And Meat Quality Of Calves, Jesse Fulton Jan 2016

The Effect Of Copper And Zinc Source On Pre-Weaning Performance Of Cows, Health And Performance Of Suckling Calves, And Post-Weaning Feedlot Performance, Carcass Composition, And Meat Quality Of Calves, Jesse Fulton

Electronic Theses and Dissertations

During gestation an elevated level of nutrient intake is required by the cow in order to meet the requirements of the maturing fetus and if these requirements are not met, changes in fetal development can occur. However, little is understood about the effects of gestational manipulation of specific nutrients, such as minerals, on progeny growth, performance and carcass traits. Previous research supports the hypothesis that minerals provided in an organic form should be more soluble and readily available to the body for absorption. Therefore the objectives of this study were to determine if source of gestational and post-natal Cu and …

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Land Cover Land Use Change And Soil Organic Carbon Under Climate Variability In The Semi-Arid West African Sahel (1960-2050), Amadou M. Dieye Jan 2016

Land Cover Land Use Change And Soil Organic Carbon Under Climate Variability In The Semi-Arid West African Sahel (1960-2050), Amadou M. Dieye

Electronic Theses and Dissertations

Land Cover Land Use (LCLU) change affects land surface processes recognized to influence climate change at local, national and global levels. Soil organic carbon is a key component for the functioning of agro-ecosystems and has a direct effect on the physical, chemical and biological characteristics of the soil. The capacity to model and project LCLU change is of considerable interest for mitigation and adaptation measures in response to climate change. A combination of remote sensing analyses, qualitative social survey techniques, and biogeochemical modeling was used to study the relationships between climate change, LCLU change and soil organic carbon in the …

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Use Of Extraction Technologies In Food Safety Studies, Changling Qiu Jan 2016

Use Of Extraction Technologies In Food Safety Studies, Changling Qiu

Electronic Theses and Dissertations

Food safety has become a top concern in our society. The public in general is increasingly concerned about the safety of the food products they consume every day as more and more food contamination incidents and widespread recalls arise. It is necessary to trace any presence and/or the concentration levels of contaminants, pesticides, herbicides, or other harmful substances in food samples. Sample preparation is a crucial step in a food analytical method, as it takes up most of the total analysis time, contributing highly to the total cost of analysis and greatly influencing the results of the analysis. Traditional extraction …

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Manufacture, Concentration, And Functionality Of Micellar Casein Concentrate, Dustin Grossbier Jan 2016

Manufacture, Concentration, And Functionality Of Micellar Casein Concentrate, Dustin Grossbier

Electronic Theses and Dissertations

This research has been structured into 3 major parts. The first part evaluates a centrifugal evaporator to concentrate micellar casein concentrate (MCC). The second part evaluates a wiped film evaporator (WFE) to concentrate MCC. The third part evaluates heat stability of the high concentration MCC produced by WFE. In part 1, the primary objective was to achieve >25% total solids (TS) without a loss of water removal rate associated with high solids materials. This is of importance, industrially, as this could reduce processing costs or eliminate drying all together. The major finding was that it did not offer any benefits …

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Three Overlooked Issues: Water Quality, Forage Quality, And Forage Blends Impacting The Feed Efficiency Of Dairy Cows, Ishwary Prasad Acharya Jan 2016

Three Overlooked Issues: Water Quality, Forage Quality, And Forage Blends Impacting The Feed Efficiency Of Dairy Cows, Ishwary Prasad Acharya

Electronic Theses and Dissertations

The overall objectives of the six studies were to increase the feed efficiency in lactating dairy cows. The first study evaluated the efficacy of different water sources and treatment systems on ruminal parameters using an in vitro gas production system. Outcomes of the study suggested that the source and nutrient quality of water can affect rate of ruminal fermentation. Thus, use of real farm water being offered to the cow to conduct in vitro gas production measurements may accurately predict the ruminal fermentation, digestibility and total gas production. The second study evaluated two recently developed leafy-floury corn silage hybrids against …

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Survival, Abundance, And Relative Predation Of Wild Rainbow Trout In The Deerfield Reservoir System, South Dakota, Jeremy L. Kientz Jan 2016

Survival, Abundance, And Relative Predation Of Wild Rainbow Trout In The Deerfield Reservoir System, South Dakota, Jeremy L. Kientz

Electronic Theses and Dissertations

Rainbow Trout Oncorhynchus mykiss are routinely stocked in Black Hills streams and reservoirs to enhance angling opportunities for the public, however in most cases, hatchery-reared Rainbow Trout do not successfully recruit to establish natural populations. One exception is the Deerfield Reservoir system, where it is estimated that up to 25% of the Rainbow Trout population consists of naturally produced, wild Rainbow Trout. While recruitment of wild Rainbow Trout to the Deerfield Reservoir fishery does occur, annual stockings of 12,000 hatchery Rainbow Trout have continued. In recent years, adipose fin clips were used to identify hatchery Rainbow Trout stocked into Deerfield …

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Evaluation Of The Hypothalamic Kisspeptin System Throughout The Estrous Cycle And During The Attainment Of Puberty In Gilts, Eric Steven Jolitz Jan 2016

Evaluation Of The Hypothalamic Kisspeptin System Throughout The Estrous Cycle And During The Attainment Of Puberty In Gilts, Eric Steven Jolitz

Electronic Theses and Dissertations

Kisspeptin has been demonstrated to affect reproductive cyclicity and the attainment of puberty in multiple species, presumably through its actions on GnRH and LH, as demonstrated in other species. Kisspeptin administration causes increased plasma concentrations of LH in pigs, sheep, and rats. Two experiments were conducted to evaluate 1) the hypothalamic kisspeptin system throughout various days of the estrous cycle and 2) the hypothalamic kisspeptin system during the peripubertal period in gilts. In experiment 1, 40 crossbred gilts (191 d, 121 kg) were administered an intramuscular injection of PG600. Twelve days after the administration of PG600, gilts were fed 15 …

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Changes In Wetland Conditions And Wetland Plant Communities In The Prairie Pothole Region After 50 Years, Ryann Cressey Jan 2016

Changes In Wetland Conditions And Wetland Plant Communities In The Prairie Pothole Region After 50 Years, Ryann Cressey

Electronic Theses and Dissertations

Wetlands in Stutsman County, North Dakota were revisited after 50 years to assess changes in wetland conditions and plant communities within wetland zones in the Prairie Pothole Region. In 1961-1966, Robert E. Stewart and Harold A. Kantrud conducted a study to investigate the relationship of wetland plant communities to variations of water permanence and chemistry on three study areas: Crystal Springs, Cottonwood, and Mt. Moriah. Within in this region, a severe drought occurred in 1988- 1992 followed by the longest deluge starting in 1993 with wetlands still impacted today. In 2013 and 2014, I revisited 80 of the original wetlands …

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Simulating The Impacts Of Land-Use Land-Cover Changes On Cropland Carbon Fluxes In The Midwest Of The United States, Zhengpeng Li Jan 2016

Simulating The Impacts Of Land-Use Land-Cover Changes On Cropland Carbon Fluxes In The Midwest Of The United States, Zhengpeng Li

Electronic Theses and Dissertations

Understanding the major drivers of the cropland carbon fluxes is important for carbon management and greenhouse gas mitigation in agriculture. Past studies found that agricultural land-use and land-cover (LULC) changes, such as changes in cropland production technologies, tillage practices, and planted crop species, could have large impacts on carbon fluxes. However, the impacts remain highly uncertain at regional to global scales. Satellite remote sensing is commonly used to create products with geospatial information on LULC changes. This geospatial information can be integrated into biogeochemical models to simulate the spatial and temporal patterns of carbon fluxes. We used the General Ensemble …

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Evaluation And Identification Of Soybean Aphid Resistance Sources And Mapping Of Soybean Aphid Resistance Loci In Early Maturing Soybean Germplasm Accessions, Siddhi Jeewan Bhusal Jan 2016

Evaluation And Identification Of Soybean Aphid Resistance Sources And Mapping Of Soybean Aphid Resistance Loci In Early Maturing Soybean Germplasm Accessions, Siddhi Jeewan Bhusal

Electronic Theses and Dissertations

Soybean aphid (Aphis glycines Matsumura) has been a major pest of soybean [Glycine max (L.) Merr.] in North America particularly in the northern United States and three Canadian provinces. At least four biotypes of soybean aphid have been confirmed in the United States. Identification of soybean aphid resistance sources in early-maturing soybeans and genetic characterization of new sources of resistance will facilitate to expand the gene pool of soybean aphid resistance and thus will help to develop soybean aphid resistant cultivars. To identify new sources of resistance in early maturing soybeans, 330 soybean germplasm accessions from Maturity Group (MG) I, …

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Application Of Routine Activities Theory To The Study Of Residential Armed Robbery In Ghana, Neeh Nhai Lhayea Jan 2016

Application Of Routine Activities Theory To The Study Of Residential Armed Robbery In Ghana, Neeh Nhai Lhayea

Electronic Theses and Dissertations

This study utilized Routine Activities theory to explain deterrent and motivating factors associated with residential armed robbery in Ghana. Although several studies have examined crime through the lenses of Routine Activities theory, none such studies have been dedicated to the study of residential armed robbery in Ghana. This study, therefore, attempts to fill that void by applying Routine Activities theory to the study of residential armed robbery. This research samples 56 of armed robbers in three selected prisons of contemporary Ghana to provide a fuller criminological and descriptive analysis of the offence, the offenders, motivation and guardianship to committing residential …

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Transcriptional And Post-Transcriptional Regulation Of Nodule-Specific Gene Expression In Soybean, Sajag Adhikari Jan 2016

Transcriptional And Post-Transcriptional Regulation Of Nodule-Specific Gene Expression In Soybean, Sajag Adhikari

Electronic Theses and Dissertations

Lateral roots and nodules are two important nutrient acquisition organs in soybean. The evolutionary origin of nodules from lateral roots has been highly hypothesized based on morphological similarities and genetic studies, but gene expression profiles during the formation of these organs have not been compared. In addition, the role of post-transcriptional gene regulation during nodule development has not been thoroughly explored. Bridging these knowledge gaps is crucial to develop genetic/biotechnological strategies to optimize nutrient acquisition and sustainable production of crops. To answer some of the outstanding questions about regulation of gene expression during nodule development, (i) global transcriptome analyses of …

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Cooperation And Punishment In The Arbuscular Mycorrhizal Symbiosis: Implications For Resource Exchange & Biological Market Dynamics, Jerry A. Mensah Jan 2016

Cooperation And Punishment In The Arbuscular Mycorrhizal Symbiosis: Implications For Resource Exchange & Biological Market Dynamics, Jerry A. Mensah

Electronic Theses and Dissertations

The arbuscular mycorrhizal (AM) symbiosis is arguably the world’s most abundant and important mutualism, and brings together the roots of the majority of land plants and AM fungi to great mutual advantage. The AM symbiosis can increase the uptake of nutrients, such as phosphorus (P) and nitrogen (N), and improves the abiotic and biotic stress resistance of the host plant. AM fungi have the potential to act as biofertilizers and bioprotectors in sustainable agriculture. However, despite its significance, the mechanisms that control the resource exchange between both partners in the arbuscular mycorrhizal symbiosis are largely unknown. The main aim of …

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Impact Of Dietary Bioactive Components In Chronic Diseases Using Nutrigenomics, Nutriepigenomics, And Metagenomics Approaches, Bijaya Prasad Upadhyaya Jan 2016

Impact Of Dietary Bioactive Components In Chronic Diseases Using Nutrigenomics, Nutriepigenomics, And Metagenomics Approaches, Bijaya Prasad Upadhyaya

Electronic Theses and Dissertations

Chronic diseases that include seven of the top ten leading causes of premature deaths in the United States demand more than eighty percent of all health care cost. Although typical Western diets--high fat (HF), low fiber and low vegetables-- are frequently associated with increased risk for chronic diseases like obesity, metabolic syndrome (MetS), type 2 diabetes, cardiovascular diseases (CVD), and cancer, there is a lack of mechanistic understanding of a causal relationship between diet and disease phenotypes, particularly in a clinical setting. This dissertation research aimed to address this research gap through the effects of wheat fiber-derived resistant starch type …

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Analysis Of Starch Branching Enzyme 1 (Sbe1) Gene In Maize, Abiskar Gyawali Jan 2016

Analysis Of Starch Branching Enzyme 1 (Sbe1) Gene In Maize, Abiskar Gyawali

Electronic Theses and Dissertations

A previous study revealed a quantitative trait locus (QTL) in maize on the short arm of chromosome 5 (5S) for endosperm amylose content. In that original study, both low and high amylose parental lines, H99ae and GEMS-0067 respectively, were homozygous recessive for amylose extender 1 (ae1) and the polymorphism responsible for this QTL was additive (semi-dominant). Located within the QTL interval is starch branching enzyme 1 (sbe1), which makes it a candidate gene. In order to test whether a polymorphism in sbe1 is the source of this QTL, we crossed a plant homozygous for ae1 and sbe1-Mu onto a …

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The Search For Modifiers Of The Maze Gametophyte Factor Ga1-S And Quantitative Trait Polymorphisms Emerging From Doubled-Haploid Maize Lines, Vivek Shrestha Jan 2016

The Search For Modifiers Of The Maze Gametophyte Factor Ga1-S And Quantitative Trait Polymorphisms Emerging From Doubled-Haploid Maize Lines, Vivek Shrestha

Electronic Theses and Dissertations

The project was designed to conduct two independent projects. The first project was to identify the genomic localization of the modifiers of the maize gametophyte factor (Ga1-s) and the second project was to establish and identify heritable polymorphic lines that have descended from a single doubled-haploid B73 plant. The objectives were (1) to search for modifier genes and loci on the maize chromosomes for the trait and determine genetic effects of them using QTL mapping; (2) to demonstrate the heritable polymorphism of the quantitative traits emerged from the descendants of a single doubled-haploid maize plant. Regarding the QTL …

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An Evaluation Of Feeding A Blend Of Essential Oils And Cobalt Lactate To Lactating Dairy Cows, Olivia Jayne Kuester Jan 2016

An Evaluation Of Feeding A Blend Of Essential Oils And Cobalt Lactate To Lactating Dairy Cows, Olivia Jayne Kuester

Electronic Theses and Dissertations

The objective of this study was to determine if the inclusion of a blend of essential oils and cobalt lactate (EOC) in the diet of lactating dairy cows could result in improved nutrient utilization and lactational performance in addition to assessing the application of EOC to control feed mycotoxins and spoilage. The trial was conducted in two experimental periods (Phase 1 (P1) and Phase 2 (P2)) on a commercial dairy in southwest Minnesota equipped with two robotic milking units. Phases 1 and 2 were cross over design trials with two pens. Cows were housed in two freestall pens (57 ± …

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Spatial Variability Analysis And Reclamation Of Saline-Sodic Soils In The Northern Great Plains, Girma Birru Jan 2016

Spatial Variability Analysis And Reclamation Of Saline-Sodic Soils In The Northern Great Plains, Girma Birru

Electronic Theses and Dissertations

Increased spring rainfall and higher temperatures when combined with changing landuses and extensive tile drainage installation have contributed to the development of sodic and saline/sodic soils in the Northern Great Plains. The objectives of this dissertation were: 1) determine the impact of surface chemical treatments and cover crop on crop yields and soil remediation; 2) determine and describe soil spatial variability and develop a model to identify saline-sodic soils; and 3) evaluate cation impact on dispersion of bentonite clay and selected soils. The research was conducted between 2013 and 2016 at Redfield (Argiustolls, Natrudolls, Calciustolls), White Lake (Argiudolls, Natrudolls), and …

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Impacts Of Land Use And Climate Changes On Hydrological Processes In South Dakota Watersheds, Manashi Paul Jan 2016

Impacts Of Land Use And Climate Changes On Hydrological Processes In South Dakota Watersheds, Manashi Paul

Electronic Theses and Dissertations

This study aims to evaluate the impacts of climate and land use change on the hydrology of South Dakota’s watersheds using the Soil and Water Assessment Tool (SWAT). The study analyzed the hydrologic impacts of climate and land use changes in two ways. The first aspect consists of characterizing hydrological changes between two recent decades in three representative watersheds – Bad River watershed, Skunk Creek watershed and Upper Big Sioux River watershed. Two historical land use maps (NLCD 1992 and 2011) were used to represent land use change on these watersheds, and two historical climate datasets (1981-1990 and 2005-2014) were …

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Raptors In Temperate Grasslands: Ecology Of Ferruginous Hawk, Golden Eagle, And Northern Harrier In The Northern Great Plains, Shubham Datta Jan 2016

Raptors In Temperate Grasslands: Ecology Of Ferruginous Hawk, Golden Eagle, And Northern Harrier In The Northern Great Plains, Shubham Datta

Electronic Theses and Dissertations

Ferruginous hawks (Buteo regalis) are a grassland and shrubland obligate nesting raptor and prefer lightly grazed pasture or idle areas for nesting. Their population reportedly declines in number if more than 30% of an area is cultivated and they rarely nest in areas dominated by croplands. Golden eagles (Aquila chrysaetos) are long-lived raptors with high nest-site fidelity and relatively low reproductive success. Population trends of golden eagles in western United States are unclear although long-term monitoring of populations shows declines in occupancy and breeding performance. Northern harriers (Circus cyaneus) prefer relatively open grasslands and …

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Morphologic And Transcriptomic Response To Weed Pressure In Multiple Maize (Zea Mays L.) Selections And Teosinte (Zea Mays L. Ssp Parviglumis) Lines, Stephanie A. Bruggeman Jan 2016

Morphologic And Transcriptomic Response To Weed Pressure In Multiple Maize (Zea Mays L.) Selections And Teosinte (Zea Mays L. Ssp Parviglumis) Lines, Stephanie A. Bruggeman

Electronic Theses and Dissertations

Sweet corn (Zea mays L. convar. saccharata var. rugosa) and modern dent variants (field maize, Zea mays L. indentata) have varying degrees of weed tolerance (ability to maintain yield under weed stress). Maize retains ~30% of its ancestral teosinte’s (Zea mays ssp parviglumis) genetic base. Transcriptomic response to weed pressure in maize and teosinte can lead to manipulation of the maize genome to minimize crop yield loss due to weed presence. In maize and teosinte under weed-free and weedstressed conditions, the objectives of this study were: 1) to evaluate transcriptomic responses of 2 teosinte lines; 2) …

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Quantitative Trait Loci Analysis Of Low Temperature Responses In Grapevine F2 Population, Mani Awale Jan 2016

Quantitative Trait Loci Analysis Of Low Temperature Responses In Grapevine F2 Population, Mani Awale

Electronic Theses and Dissertations

Freezing injury, caused by freezing temperatures in the late fall, midwinter, or early spring, can result in significant loss to grape growers. The damage may range from the partial damage of parts of the plants to the total death of the plant, and may vary between years. Freezing tolerance is a multi-genetic, complex quantitative trait that involves many related traits like dormancy induction, growth cessation, acclimation, deacclimation and bud break. Developing an understanding of the genetics behind the complex trait requires connecting the phenotype with the genotype to enable discovering the underlying genes that can contribute to quantifiable differences between …

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Enhancing The Industrial Potential Of Filamentous Cyanobacteria, Tylor J. Johnson Jan 2016

Enhancing The Industrial Potential Of Filamentous Cyanobacteria, Tylor J. Johnson

Electronic Theses and Dissertations

The objectives of this project were to improve the industrial potential of filamentous N2-fixing cyanobacteria by increasing its biofuel tolerance, and to evaluate the economic feasibility and environmental impacts of a theoretical, cyanobacteria-based biofuel production facility. To develop a method to quantify filamentous cyanobacteria in dilute culture media, a dual-stained fluorescence assay was evaluated. While the viable cell stain (SYTO® 9) was accurate, the non-viable cell stain (propidium iodide) also bound to viable cells. Additional non-viable cell stains were evaluated, but none were accurate at quantifying viability. Thus we concluded that the viable cell stain SYTO® 9 is a reliable …

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Evaluating Steel Byproducts And Natural Minerals For Phosphate Adsorption From Agricultural Subsurface Drainage, Bjorn Sellner Jan 2016

Evaluating Steel Byproducts And Natural Minerals For Phosphate Adsorption From Agricultural Subsurface Drainage, Bjorn Sellner

Electronic Theses and Dissertations

The loss of phosphorus (P) from agricultural soils to surface waters is recognized as a key contributing factor to eutrophication in surface waters. Recent studies have shown that in addition to surface runoff, subsurface drainage can contribute substantially to the loss of P from soils. The use of adsorption materials to bind P has emerged as a promising technology for P removal. The objective of this study was to perform batch and column experiments to investigate the P adsorption potential of several materials for agricultural subsurface drainage treatment. Laboratory batch adsorption experiments were performed to determine the P adsorption capacities …

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Restoration Of Eroded Lands With Biochar As Soil Amendment In South Dakota, Saroop S. Sandhu Jan 2016

Restoration Of Eroded Lands With Biochar As Soil Amendment In South Dakota, Saroop S. Sandhu

Electronic Theses and Dissertations

Biochar is produced from incomplete pyrolysis of plant biomass. Due to the unique properties of biochar such as a higher number of micropores, surface area and carbon content, and recalcitrant nature of carbon, biochar is hypothesized to improve physical and hydrological properties of soil. This study assesses the impact of biochar on soil organic carbon, physical and hydrological properties of two landscape positions under a corn (Zea mays L.)-soybean (Glycine max L.) rotation. Three types of biochar including corn stover, ponderosa pine (Pinus ponderosa Lawson and C. Lawson) wood residue, and switchgrass (Panicum virgatum L.) were applied in the field …

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Improving Feed Efficiency Through Forage Strategies For Increasing Dairy Profitability And Sustainability, Jon Patrick Pretz Jan 2016

Improving Feed Efficiency Through Forage Strategies For Increasing Dairy Profitability And Sustainability, Jon Patrick Pretz

Electronic Theses and Dissertations

Three studies were conducted to determine production parameters and study specific hypothesis in regard to improving feed efficiency through various forage utilization strategies with or without the inclusion of various supplemented products. The first study evaluated the supplementation of a cobalt-lactate product and its effects on fiber digestibility and milk production parameters when fed to cows consuming a 70% forage diet. Treatments included: 1) CONTROL diet containing 12.5 mg/cow/d of cobalt (carbonate carbonate) and 2) TEST diet being the same basal diet but including an additional 50 mg/cow/d of cobalt via a 1% Co-lactate product (Co-Max®). In a feeding trial …

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Diversity Of Free-Living Nitrogen Fixing Bacteria In The Badlands Of South Dakota, Bibha Dahal Jan 2016

Diversity Of Free-Living Nitrogen Fixing Bacteria In The Badlands Of South Dakota, Bibha Dahal

Electronic Theses and Dissertations

Biological Nitrogen Fixation is carried out by a highly diverse group of members of the domains Bacteria and Archaea which express a nitrogenase enzyme complex and are termed diazotrophs. The best known diazotrophs form symbiotic associations with plants, but free-living nitrogen fixing bacteria also contribute a substantial amount of nitrogen to ecosystems, including arid lands. The aim of this study was to isolate free-living diazotrophs from the soil crusts of sod tables of South Dakota Badlands. Samples were obtained from sod tables and the surrounding base (matrix) in spring and fall of 2014. A culture dependent approach was used to …

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Using Remote Sensing And Biogeographic Modeling To Understand The Oak Savannas Of The Sheyenne National Grassland, North Dakota, Usa, Mandira Sigdelphuyal Jan 2016

Using Remote Sensing And Biogeographic Modeling To Understand The Oak Savannas Of The Sheyenne National Grassland, North Dakota, Usa, Mandira Sigdelphuyal

Electronic Theses and Dissertations

Oak savannas are valuable and complex ecosystems that provide multiple ecosystem goods and services, including grazing for livestock, watershed regulation, and recreation. These ecosystems of the woodland-prairie ecoregion of the Midwestern United States are, however, in danger of disappearing. The Sheyenne National Grassland, North Dakota, a protected Prairie grassland-savanna, is a representative of such rare habitats, where oak savanna is found at the landscape scale. In this research, I map the distribution patterns of oak savanna in the Sheyenne using a combination of remote sensing and geospatial datasets, including landscape topography, soils, and fire disturbance. Further, I interpret the performance …

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