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An Optimization Procedure To Design Nozzle Contours For Hypersonic Wind Tunnels, Omar Antonio Dominguez

Open Access Theses & Dissertations

Supersonic wind tunnels allow scientists and researchers to evaluate and analyze the behaviors of objects under real-life conditions when subjected to supersonic speeds. One of the main complexities when building a wind tunnel is the design of the convergent-divergent nozzle that is used to produce high-speed and high-quality flows. To achieve supersonic speeds, this nozzle adopts a specialized approach that incorporates the complexities of flow compressibility. The compressible effect is accurately evaluated using isentropic relations, allowing for precise determination of stagnation pressure and temperature, and static pressure and temperature relevant to the desired Mach number. Isentropic equations used to define …

Implementation Of State Of New Mexico's Manual Of Procedures Psab Supplement 12 Capital Assets By A Southern New Mexico School District In Disposal Of E-Waste In The Post Covid 19 Environment, Hector Serrato Giron

Open Access Theses & Dissertations

The COVID-19 pandemic has caused diverse social, economic, and political challenges. The particular challenge that was the focus of this study is the upsurge in electronic use and consequent upsurge in electronic waste. This was caused by the implementation of online instructional delivery processes during Covid-19 (Ermakova, 2021), the switch to home offices (Adejumo & Oluduro, 2021) and the fact that school districts have directed massive financial investments to instructional technology (Baldé & Kuehr, 2021). This trend of heightened e-waste generation is likely to continue (Jiang et al., 2021).

I used a qualitative approach to address the two research questions. …

Green Analytical Methods For The Determination Of Perfluorocarboxylic Acids (Pfcas) And Fluorotelomer Alcohols (Ftohs) In Water, Ahsan Habib

Open Access Theses & Dissertations

Per- and polyfluoroalkyl substances (PFAS) are a large group of synthetic organic compounds manufactured for their heat, water, and stain-resistant properties. PFAS can be found ubiquitously in the environment because they are widely used in everyday consumer products such as fast-food wrappers, non-stick cookware, stain-resistant products, cosmetics, aqueous film-forming foams, etc. As a result, PFAS are commonly detected in surface water, wastewater, and biosolids from wastewater treatment plants (WWTPs). These are the direct sources of PFAS contamination in drinking water supplies, which are substantial sources of human exposure. Among these PFAS chemicals, two major groups are perfluoroalkyl carboxylic acids (PFCAs) …

The Role Of The Cholesterol Synthesis Pathway In Primitive Erythropoiesis, Jose Hernandez

Open Access Theses & Dissertations

Erythropoiesis is the process by which new red blood cells (RBCs) are formed and defects in this process can lead to anemia or thalassemia. The GATA1 transcription factor is an established mediator of RBC development. However, the upstream mechanisms that regulate the expression of GATA1 are not completely characterized. Cholesterol is 1 potential upstream mediator of GATA1 expression because previously published studies suggest that defects in cholesterol synthesis disrupt RBC differentiation. Here we characterize RBC development in a zebrafish harboring a single missense mutation in the hmgcs1 gene (Vu57 allele). Hmgcs1 encodes the first enzyme in the cholesterol synthesis pathway …

Evaluation Of The Efficacy Of Synthetic Glycovaccines Against Both Murine Acute Chagas Disease And Cutaneous Leishmaniasis, Colin D. Knight

Open Access Theses & Dissertations

Chagas disease (CD) and cutaneous leishmaniasis (CL) are neglected tropical diseases caused by the protozoan trypanosomatids, Trypanosoma cruzi and Leishmania spp., respectively. There are approximately 6-8 million people infected with T. cruzi worldwide and ~300,000 people in the US. Between 700,000 and 1.2 million new cases of CL occur worldwide yearly. The approved chemotherapies for both diseases are partially effective and may cause serious adverse events, resulting in premature treatment interruption. Moreover, no effective vaccine for either disease is available. Therefore, developing a vaccine that would provide effective cross-protection against both diseases would provide a cost-effective alternative to the existing …

Tess Of The D'Urbervilles -- A Pure Survivor An Analysis Of Thomas Hardy, Victorian Women, & Modern Media, Jesse C. Marin

Open Access Theses & Dissertations

Context is vital to understanding the circumstances and the society that produced Thomas Hardy’s novel. As such, I will be reviewing the era through canonically established authors, the literary trope that would condemn women and firmly entrench itself in England’s national identity, and political movements guided by the law of Victorian England. This will showcase the hurdles of basic women’s rights that would continue throughout the reign of Queen Victoria, as well as the dangers that would be faced in the public and domestic spheres, endangering a woman’s very life. When tied together W.T. Stead’s expose in the Pall Mall …

Repositioning Propranolol To Block Mitogenic Signaling In Breast Cancer, Alexa Noel Montoya

Open Access Theses & Dissertations

Breast cancer is the second most diagnosed cancer among women and is about 30% of all new cases of female cancers each year. It is projected that 1 in 8 every U.S. woman (about 13%) develop invasive breast cancer over the course of her lifetime. While advances in cancer research have made it possible to elucidate several breast cancer genomic subtypes, and develop new novel therapies, many of these agents are associated with significant toxicity, as well as high costs. A retrospective cross-sectional study of 404 breast cancer patients was performed to determine the effect of β-blocker usage on tumor …

Metrics For Comparison Of Complex Networks, Clarissa Reyes

Open Access Theses & Dissertations

Heuristic network statistics are used as a preliminary approach to identify change across networks. In networks where there is known node correspondence (KNC), conventional network comparison methods include taking a norm of the difference matrix, or calculating dissimilarity measures like DeltaCon and cut distance. Since different KNC measures provide varying insight to the network comparison problem, we propose employing Rank Score Characteristic Functions (RSCFs) and the rank-score process as a method for reaching a consensus when ranking quantified change across multiple pairs of networks â?? which is particularly useful for ranking change across subpopulations or subgraphs. Additionally, we propose a …

Lizard Communities In A Shifting Landscape: The Current State Of Insectivorous Lizard Communities In The Jornada Basin Between Grassland, Mesquite Dune, And Creosote Bush Habitats In A Semi-Arid Landscape Undergoing Shrubification, Julie Marie Schlichte

Open Access Theses & Dissertations

Lizard communities in arid lands can act as model systems of how diversity and abundance are impacted in the face of ongoing climate variability and change, as they are sensitive to shifts in precipitation, temperature, and changing vegetation structure. The main research question we hope to answer is how the community composition of lizards varies between dominant vegetation types (Mesquite dunes, grasslands, and Creosote Bush flats). Nine sites (3 of each dominant vegetation type) with 16 pitfall traps each (n = 144) were surveyed from June 2016 -- June 2017. 12 lizard species were captured, consisting of 923 total captures …

Evolution Of Forest Bitis (Macrocerastes) In Africa: Phylogeography, Population Genetics, And Potential As A Model For Batesian Mimicry, Eugene Richard Vaughan

Open Access Theses & Dissertations

The major biogeographical patterns characterizing the diversification of widely distributed species in the African rainforest remain poorly understood because of the low number of well-sampled studies that are focused on this region. I examine the phylogeography and population genetics of two broadly sympatric sister lineages of large African forest vipers (genus Bitis, subgenus Macrocerastes), the rhinoceros viper (B. nasicornis) and the Gaboon vipers (B. gabonica and B. rhinoceros). Despite their close relationship, these two lineages have notably different patterns of divergence in time and space. A time-calibrated phylogeny with sequence data from five genes, and population structure and PCA analyses …

Exploring Aging Using The Selection, Optimization, And Compensation (Soc) Framework In Conjunction With Kinematic Gait And Verbal Fluency Task Analysis In Healthy Adults, Emily Ann Chavez

Open Access Theses & Dissertations

This multi-study dissertation examined dual-task performance in young and middle-aged adults using verbal fluency tasks (VFT) during different walking scenarios (baseline, performing a VFT, walking narrowly, and performing a VFT while walking narrowly) as well as the Selection, Optimization, and Compensation (SOC) model. Thirty adults (15 young adults (YA; 19-44 years) and 15 middle-aged adults (MA; 45-65 years) participated in this study. Overall, there were no significant differences between groups when data was examined in short (means of means approach) and long-form (incorporating all data), when analyzing clustering and switching strategies, gait speed variability, or dual-task costs. Overall, these three …

Study Of Human Circadian Protein (Hrory) And Lipid-Protein Interaction In Giant Virus (Pbcv-1), Laila Noor

Open Access Theses & Dissertations

Project 1: Circadian rhythm is a 24-hour cycle that regulates physical and behavioral changes such as sleep-wake patterns in humans, tailoring the daily light and dark changes. Long-term disruption in circadian rhythms can cause sleep disorders such as sleep apnea, insomnia, et al. Limited research has been done on potential drugs to treat against circadian related sleep disorders. Inside the cell at molecular level, the circadian rhythm is regulated by interlocked time-delayed feedback loops, which involve positive and negative transcriptional regulators. Experimental results showed transcriptional factors Retinoic Acid Receptor-Related Orphan Receptors (RORs) improve the stability and functionality of the circadian …

Revolutionizing Fracture Fixation In Diabetic And Non-Diabetic Rats: High Mobility Group Box 1-Based Coating For Enhanced Osseointegration, Alexandra Arteaga, Cláudia Cristina Biguetti, Bhuvana Lakkasetter Chandrashekar, Javier La Fontaine, Danieli C. Rodrigues

School of Podiatric Medicine Publications

Chronic inflammation and hyperglycemia in diabetic patients increase the risk of implant failure and impaired fracture healing. We previously developed and characterized a titanium (Ti) coating strategy using an imidazolium-based ionic liquid (IonL) with a fully reduced, non-oxidizable High Mobility Group Box 1 (HMGB1) isoform (Ti-IonL-HMGB1) to immunomodulate tissue healing. In this study, we used an open reduction fracture fixation (ORIF) model in non-diabetic (ND) and diabetic (D) rats to further investigate the effectiveness of this Ti-IonL-HMGB1 coating on orthopedic applications. Ninety male Lewis rats (12–15 weeks) were divided into D (n = 45) and ND (n = …

The Blueberry Gall Midge Complex And Its Specialist Parasitoids, Monique Michele Raymond

Master's Theses and Capstones

The cosmopolitan blueberry gall midge complex causes serious damage to the terminal vegetation of blueberry plants. The nature of their infestation, paired with prolonged periods of abundance, requires an integrated pest management approach. Of all known parasitoids present in the system, members of the subfamily Platygastrinae are the only oligophagous clade specialized against true gall midges. In this study, we present the results of blueberry gall midge and platygastrid surveys in high- and low-bush blueberry crops in the northeastern and southeastern United States, along with an identification key, with emphasis on blueberry parasitoid Synopeas species to facilitate their identification.

Assessment Of A Pharmacist-Led Antibiotic Time-Out For Transition Of Iv Vancomycin To Oral Linezolid, Mary S. Vogel, Jefferson Cua, Erika Dittmar, Timothy Gauthier, Kelsey N. Williams

Nursing & Health Sciences Research Journal

Introduction: Intravenous (IV) vancomycin requires therapeutic drug monitoring and line placement and may prolong hospital stay. Linezolid requires less monitoring, is orally bioavailable, and may expedite transitions of care. This study assessed the impact of a pharmacist-led antibiotic timeout for the transition from IV vancomycin to oral linezolid. Methods: This single-center, quasi-experimental study included admitted adult patients receiving IV vancomycin for over 48 hours. Patients receiving vasopressors, of immunocompromised status, or with specific antibiotic indications were excluded. The primary outcome was the pharmacist intervention acceptance rate. Secondary outcomes included median hospital length of stay, median antibiotic treatment days, and incidence …

Patterns In Winter Stonefly Distribution Along A River Continuum And Land-Use Gradient In Northwest Arkansas Streams, Zachary Tipton

Graduate Theses and Dissertations

Freshwater ecosystems are facing a crisis with extinction rates of aquatic species exceeding those of their terrestrial counterparts by up to fivefold. This decline is predominantly attributed to evolving land use patterns within watersheds, leading to chemical and physical transformations in freshwater habitats. Northwest Arkansas (NWA) represents one of the fastest-growing regions in the United States, undergoing substantial shifts in land use. Consequently, the status of aquatic life in this region remains uncertain. Addressing this concern, the latest Arkansas Wildlife Action Plan emphasizes the necessity of distribution and population data to guide conservation efforts for Species of Greatest Conservation Need …

A Cross-Sectional Study On The Impact Of The Covid-19 Pandemic On Sport-Related Concussion Clinical Presentation Within Adolescents And Adults, Emily Mcindoe

Graduate Theses and Dissertations

Introduction. The COVID-19 pandemic spanned across the globe in March 2020 and has since significantly impacted human life. There is evidence that supports symptom exacerbation and an increase in anxiety and depression in clinical presentation post-COVID-19 pandemic compared to pre-COVID-19 for multiple medical diagnoses. These medical diagnoses include migraines, post-traumatic stress disorder (PTSD), obsessive-compulsive disorder (OCD), and mild cognitive impairment. The effect that the pandemic had on the clinical presentation of sports-related concussions is understudied. It is possible that the COVID-19 pandemic has altered the clinical presentation of concussions as seen in other medical diagnoses. Given the increased reporting of …

Habitat Associations Of Plains Spotted Skunk (Spilogale Interrupta) Across The Plains Ecoregion. And The Landcover Occupancy Models Of The Gray Fox (Urocyon Cinereoargenteus) In The Southeastern Plains Region In Arkansas, Michael Shaw

Graduate Theses and Dissertations

Much of the landscape of the United States has been altered by humans, leading to the eradication of most populations of large mammalian predators. Consequently, many species of mammalian mesopredators (medium-sized mammalian predators) have come to dominate the landscape. Species such as the gray fox (Urocyon cinereoargenteus) may appear to be on the rise and doing well due to their widespread range, but at a local scale may need monitoring and less is known in areas of its range. Others such as the plains spotted skunk have a wide range across the plains but are on the decline even with …

Assessment Of Dietary Energy And Amino Acid Diet Formulation In The Modern Broilers, Matheus Freitas Costa

Graduate Theses and Dissertations

As a result of the advancement of genetics, understanding broiler requirements for dietary energy and amino acids is essential for improving live performance and carcass characteristics. The energy system used to formulate diets in poultry is based on metabolizable energy (ME); this equation can be described as the total amount of energy in the feed minus gases and feces. However, the net energy (NE) system may be the best depiction of the energy utilized by birds for production and maintenance purposes once the heat increment (HI) is measured. Thus, a series of studies were conducted to establish the responsiveness of …

Geospatial Analysis Of Weathering And Recession On Architectural Limestone At The 1891 Powerhouse/Icehouse In Eureka Springs, Arkansas, Stuart Bruce Wright

Graduate Theses and Dissertations

The objective of this study of the architectural limestone of the 1891 Powerhouse/Icehouse in Eureka Springs, Arkansas was to analyze the environmental factors that influenced the deterioration and surface recession of this historical stone structure. The focus of this research was to examine and establish a baseline study that may assist in future monitoring and documentation of this historic limestone structure on stone weathering. A replicable methodology was specifically created toward this baseline research in hopes that it represented a solid baseline study. Observations and data analyses revealed the relationship between the architectural limestone building structure and the dominating recession …

Tree-Ring Reconstruction Of Ouachita River Streamflow, Keaton Cade Jenkins-Joyce

Graduate Theses and Dissertations

The Ouachita River drains the Ouachita Mountains and Upper Coastal Plain in Arkansas and Louisiana. The Ouachita River is used for navigation, power generation, recreation, water supply, and wastewater treatment. The river has been prone to low flows during drought and extreme flooding, which were principal justifications for the construction of three large multipurpose dams on the stream. It is likely that the use of the Ouachita River will be stressed by future population growth, economic expansion, and climate change. For this study, tree-ring chronologies from various locations in and near the Ouachita River drainage basin were used to reconstruct …

Tissue-Engineered Models For Investigating Nerve Infiltration In Fibrotic Microenvironments, Nikolas Ala-Kokko

Graduate Theses and Dissertations

Neuron infiltration is involved in a multitude of diseased states and is critical in the regeneration of physiologic conditions. Modeling of innervation in three-dimensional, heterogenous, environments would allow early investigation in the crosstalk of neurons and native cells in normal and pathophysiologic microenvironments to gain an understanding of mechanistic functions. This would allow for greater insight into the role of metabolism, cell adhesion, microenvironmental alternations, cellular crosstalk, and signaling pathways that play a role in the promotion and prevention of neurite growth. In this thesis, with the construction of collagen-based hydrogels as the foundation for cell culture, we investigate cell …

Determination Of P Availability In Feedstuffs And The Effect Of Feedstuffs And Anti-Nutritional Factors On Secretory Iga Production And Host Nutrient Losses In Poultry, Benjamin Parsons

Graduate Theses and Dissertations

The availability of P in feedstuffs and the effect of feedstuffs, feed additives, and anti-nutritional factors on secretory IgA (sIgA) production in chickens were evaluated. A rapid method was developed using the precision-fed rooster assay to evaluate phytic acid disappearance, P digestibility, and phytase efficacy. Further, exogenous phytase was found to be effective at degrading myo-inositol 1,2,3,4,5,6-hexakis, however, the enzyme was less efficient at P release from lower inositol phosphates. The availability of P in feedstuffs was found to be affected by dietary Ca content, where increasing Ca linearly reduced (P < 0.05) both phytic acid hydrolysis and P digestibility. For example, the standardized ileal digestibility of P was reduced from 73 to 47% in soybean meal when the dietary Ca content was increased from 0.30 to 0.75%. The digestibility of P in distillers dried grains with solubles (DDGS) and corn fermented protein (CFP), however, was high across all Ca levels (71 to 80%). Relative P bioavailability based on tibia bone ash was also found to be high for DDGS and CFP, being 81 and 78%, respectively. Upon further evaluation, it was observed that utilizing low dietary Ca levels (0.30%) when P digestibility in individual plant-based feedstuffs was determined overestimated the P digestibility in practical grower diets by up to 16 percentage units. Utilization of higher Ca levels (0.75%) when P digestibility in individual plant-based feedstuffs was determined, however, resulted in calcualted P digestibility values that were within 1 to 3 percentage units of the measured digestibility in practical grower diets. Aside from P, feedstuffs were also evaluated to determine their effect on sIgA production in the intestine. Roosters excreted approximately 6 to 30 mg of sIgA / 24 h. Further, the proportional contribution of sIgA to total endogenous amino acid (AA) losses ranged from 1 to 13%, with the greatest contribution being observed for Trp. The addition of casein to a protein-free diet increased (P < 0.05) sIgA production in both roosters and broiler chickens. There was no change (P > 0.05) in sIgA production compared with the protein-free diet …

Feed Value And Utilization Of Corn Residue: Implications For Cow Performance And Grazing Strategies, Kaylee E. Wheeler

Department of Animal Science: Dissertations, Theses, and Student Research

Two experiments were conducted to determine the correlation of corn residue feed value and utilization on cow performance and potential grazing strategies. A qualitative observation of corn residue grazing by 13 cattle herds across Nebraska was conducted over two years. Based on producer reported grain yields and stocking rates, it was found that these producers were generally not as aggressive as the recommended 1.2 animal unit months (AUM) for each 6,280 kg/ha (100 U.S. bushels/acre) of harvested grain. They stocked 17 to 101% of the recommendation and on average used 63% of the carrying capacity. Across herds, average body condition …

Predicting Body Weight Of Cattle And Nutrient Digestion Of Individual Sweet Bran Components To Improve Beef Cattle Production Efficiency, Dalton J. Anderson

Department of Animal Science: Dissertations, Theses, and Student Research

Efficiency is of high importance to beef cattle producers to ensure that beef cattle are being raised without unnecessary resource use. Two separate experiments were conducted to evaluate potential strategies to improve efficiency in beef cattle production. A metabolism study was conducted to evaluate digestion parameters of individual Sweet Bran components. The objective was to determine the effects of diet components on nutrient digestion and rumen fermentation parameters. The individual components of Sweet Bran (Corn bran, solvent-extracted germ meal, and corn steep liquor) were included at 40% diet dry matter (DM) in a steam-flaked corn (SFC) based diet. A SFC-based …

Investigation Of Breeding Objectives And Indexes-In-Retrospect, Hunter F. Valasek

Department of Animal Science: Dissertations, Theses, and Student Research

This thesis presents two projects that investigate the impacts of breeding objectives and indexes-in-retrospect within the beef cattle industry. The first project synthesized how changes due to planning horizon, breeding system, and sale endpoint in the economic breeding goal of cattle influence the relative emphasis of traits as well as the re-ranking of selection candidates. A total of three breeding systems that represent straightbred and crossbred cattle were used along with six planning horizons (2, 5, 10, 20, 30, and 50 yrs.) for both a weaning and slaughter point of sale. The combination of these different breeding objective attributes resulted …

The Evaluation Of Feed Additives On Reducing Enteric Methane Production From Cattle, Reba L. Colin

Department of Animal Science: Dissertations, Theses, and Student Research

Environmental sustainability can be positively impacted by the inclusion of feed additives to reduce enteric methane production from cattle. Methane production can be affected by feed additives that either alter the rumen environment or act as methanogenesis inhibitors. A reduction in methane from cattle can contribute to meeting carbon neutrality.

A metabolism study was conducted to evaluate Alga 1.0, a product containing bromoform, fed to cattle to evaluate the effects on gas emissions. Treatments were (0, 69, or 103 g/d Alga 1.0) fed in a corn-based diet. Headbox-style indirect calorimeters were used to measure gas emissions. Feeding Alga 1.0 linearly …

Cumulative Rights Infringement In British Columbia Treaty 8 Territory: The Need For A Renewed Environmental Decision-Making Framework Under Treaty Law, Rebeca M. Gimenez

UBC Law Review

No abstract provided.

Chemical Investigation Of Dichloromethane Extract Of Aloe Vera Peels: An Agricultural Waste, Nazmul Huda

Theses and Dissertations

Aloe barbadensis Miller, commonly called Aloe Vera, is a widely popular succulent plant species cultivated across subtropical regions worldwide from India to the Tex-Mex border. Besides its historical uses, Aloe juice has garnered attention as a potential remedy for various ailments, particularly in treating various skin conditions and facilitating wound recovery, including obesity, diabetes, hepatitis, Crohn's disease, and ulcerative colitis. Regrettably, the agricultural practice following sap extraction involves discarding Aloe vera peels, constituting agricultural waste. As part of our continuous research on extraction, isolation, separation, and spectral characterization of value-added chemicals present in waste botanicals herein, …

Age-Related Oligodendrocyte Lineage And Learning Abnormalities Driven By Nf1 Mutation In Mice, Saul Lopez

Theses and Dissertations

Neurofibromatosis Type 1 (NF1) is an autosomal dominant disease caused by mutations in the NF1 gene, on chromosome 17. NF1 patients suffer from a number of neurological issues including learning deficits and increased risk of age-related dementia. Additionally, NF1 patients present with multiple white matter and myelin abnormalities. Whether and how myelin abnormalities impact learning in NF1 is not known; therefore, we aimed to gain insights on potential links between Nf1 mutation and learning issues Unpublished data indicate that NF1 female-but not male- mice with Nf1+/- germline mutation show defects in a myelin-regulated learning/memory test (the complex wheel; CW) at …