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Navigating Transitions: Utilizing Autoethnographic Writing Prompts To Support Nontraditional College Students, Brijet Lynn Beazer May 2024

Navigating Transitions: Utilizing Autoethnographic Writing Prompts To Support Nontraditional College Students, Brijet Lynn Beazer

Graduate Theses and Dissertations

This study explores the transition nontraditional students undergo as they embark on their college journey and the unique challenges they face. Leveraging autoethnographic writing prompts as an intervention strategy, the project employed a participatory approach over virtual platforms to capture the tapestry of experiences and connect participants to form a supportive community. Participants included older individuals with work experience, some who experienced parenthood, or those returning after an extended break. Through crafted prompts, individuals shared their academic journey, balancing work, and family responsibilities. The reflections gathered provide valuable data, offering insights into the challenges and triumphs of nontraditional students. The …


Sheep Grazing Influences The Abundance, Diversity, And Community Composition Of Wild Bees And Other Insects In Livestock Pastures, Roshani Sharma Acharya, Timothy B. Leslie, Joan Burke, Kusum Naithani, Emily Fitting, Kelly Loftin, Neelendra K. Joshi May 2024

Sheep Grazing Influences The Abundance, Diversity, And Community Composition Of Wild Bees And Other Insects In Livestock Pastures, Roshani Sharma Acharya, Timothy B. Leslie, Joan Burke, Kusum Naithani, Emily Fitting, Kelly Loftin, Neelendra K. Joshi

Entomology and Plant Pathology Faculty Publications and Presentations

Pollinators contribute to the establishment of perennial native forages, but little is known about the effect of grazing practices on pollinator abundance and diversity in livestock pasture ecosystems. Grazing reduces floral resources available to bees and other insects, and as a result, may influence their communities. The main objective of this study was to examine the impact of sheep grazing on bees and other non-bee insects in livestock pasture established with seed mixes of native forb/legume/grass and warm season grasses. Each pasture was divided into two halves (in a split-plot design) using an electric fence in which one plot was …


The Causes And Consequences Of Behavioral Plasticity In Anti-Predatory Defense And Mate Choice In Tropical Butterflies, Sushant Potdar May 2024

The Causes And Consequences Of Behavioral Plasticity In Anti-Predatory Defense And Mate Choice In Tropical Butterflies, Sushant Potdar

Graduate Theses and Dissertations

Behavioral plasticity, where individuals change their behaviors in response to varying environmental and social conditions, affects major evolutionary trajectories. But how individuals change these behaviors under certain social situations, and what the genetic causes and consequences of such behavioral changes are in response to social environments are yet to be fully understood. I address these questions in the context of anti-predatory behaviors (chapter 1), and mate choice (chapters 2, 3, 4) in tropical butterflies. In the context of anti-predatory behaviors, I found predator-specific behavioral changes in toxic Heliconius butterflies, suggesting variance in predation pressures and butterfly recognition of bird calls. …


Bootstrapping For Estimating The Conservative Kill Ratio Of The Surrogate To The Pathogen For Use In Thermal Process Validation At The Industrial Scale, Arshpreet Kaur Khattra, Surabhi Wason, Kevin Thompson, Andy Mauromostakos, Jeyamkondan Subbiah, Jennifer C. Acuff May 2024

Bootstrapping For Estimating The Conservative Kill Ratio Of The Surrogate To The Pathogen For Use In Thermal Process Validation At The Industrial Scale, Arshpreet Kaur Khattra, Surabhi Wason, Kevin Thompson, Andy Mauromostakos, Jeyamkondan Subbiah, Jennifer C. Acuff

Food Science Faculty Publications and Presentations

A surrogate is commonly used for process validations. The industry often uses the target log cycle reduction for the test (LCRTest) microorganism (surrogate) to be equal to the desired log cycle reduction for the target (LCRTarget) microorganism (pathogen). When the surrogate is too conservative with far greater resistance than the pathogen, the food may be overprocessed with quality and cost consequences. In aseptic processing, the Institute for Thermal Processing Specialists recommends using relative resistance (DTarget)/(DTest) to calculate LCRTest (product of LCRTarget and relative resistance). This method uses the mean values …


Genetic Dissection Of Diverse Seed Coat Patterns In Cowpea Through A Comprehensive Gwas Approach, Haizheng Xiong, Yilin Chen, Waltram Ravelombola, Beiquan Mou, Xiaolun Sun, Qingyang Zhang, Yiting Xiao, Yang Tian, Qun Luo, Ibtisam Alatawi, Kenani Edward Chiwina, Hanan Mohammedsaeed Alkabkabi, Ainong Shi May 2024

Genetic Dissection Of Diverse Seed Coat Patterns In Cowpea Through A Comprehensive Gwas Approach, Haizheng Xiong, Yilin Chen, Waltram Ravelombola, Beiquan Mou, Xiaolun Sun, Qingyang Zhang, Yiting Xiao, Yang Tian, Qun Luo, Ibtisam Alatawi, Kenani Edward Chiwina, Hanan Mohammedsaeed Alkabkabi, Ainong Shi

Poultry Science Faculty Publications and Presentations

This study investigates the genetic determinants of seed coat color and pattern variations in cowpea (Vigna unguiculata), employing a genome-wide association approach. Analyzing a mapping panel of 296 cowpea varieties with 110,000 single nucleotide polymorphisms (SNPs), we focused on eight unique coat patterns: (1) Red and (2) Cream seed; (3) White and (4) Brown/Tan seed coat; (5) Pink, (6) Black, (7) Browneye and (8) Red/Brown Holstein. Across six GWAS models (GLM, SRM, MLM, MLMM, FarmCPU from GAPIT3, and TASSEL5), 13 significant SNP markers were identified and led to the discovery of 23 candidate genes. Among these, four specific …


Ability Of Genomic Prediction To Bi-Parent-Derived Breeding Population Using Public Data For Soybean Oil And Protein Content, Chenhui Li, Qing Yang, Bingqiang Liu, Xiaolei Shi, Zhi Liu, Chunyan Yang, Tao Wang, Fuming Xiao, Mengchen Zhang, Ainong Shi, Long Yan May 2024

Ability Of Genomic Prediction To Bi-Parent-Derived Breeding Population Using Public Data For Soybean Oil And Protein Content, Chenhui Li, Qing Yang, Bingqiang Liu, Xiaolei Shi, Zhi Liu, Chunyan Yang, Tao Wang, Fuming Xiao, Mengchen Zhang, Ainong Shi, Long Yan

Horticulture Faculty Publications and Presentations

Genomic selection (GS) is a marker-based selection method used to improve the genetic gain of quantitative traits in plant breeding. A large number of breeding datasets are available in the soybean database, and the application of these public datasets in GS will improve breeding efficiency and reduce time and cost. However, the most important problem to be solved is how to improve the ability of across-population prediction. The objectives of this study were to perform genomic prediction (GP) and estimate the prediction ability (PA) for seed oil and protein contents in soybean using available public datasets to predict breeding populations …


An Inductive Analysis Examining Factors Contributing To Student Attrition In Introductory College Chemistry Courses And Proposed Solutions., Zephaniah Daniel Greenwell May 2024

An Inductive Analysis Examining Factors Contributing To Student Attrition In Introductory College Chemistry Courses And Proposed Solutions., Zephaniah Daniel Greenwell

Graduate Theses and Dissertations

A grounded theory study was conducted to investigate possible methods for reducing the number of “D”, “F”, or “W” grades (DFW rate) in the 1st semester general chemistry course. Classroom observations conducted over the 2022-2023 school year resulted in a 17 questions survey that was distributed in both the fall 2023 and spring 2024 semesters with 157 total student responses. While these surveys were being collected, an interview protocol was developed for students and instructors, who have experience teaching or taking an introductory chemistry course. These interviews were conducted in the early spring 2024 semester. Ten undergraduate students, six graduate …


Evaluation Of Protein Turnover, Lipid Turnover, And Calcium Utilization On Broiler Breeder Performance, Cole Umberson May 2024

Evaluation Of Protein Turnover, Lipid Turnover, And Calcium Utilization On Broiler Breeder Performance, Cole Umberson

Graduate Theses and Dissertations

Broiler breeder performance is based upon egg production. Breeders are reared from day of hatch to ovulation with the main goal of controlling body weight. Maintaining body weight in breeders is highly emphasized prior to first egg as to reach optimum peak production feeding increases dramatically to meet energy needs. Energy is supplied to the breeder in three forms carbohydrates (fast energy), protein (medium energy), and fat (slow energy). Carbohydrates are quickly used by the breeders, while protein is constantly being utilized by the breeder for growth and egg production, fat is stored and used lastly as the energy requirements …


Yeast Surface Display Of Multiple Heterologous Proteins Via Molecular And Biochemical Processing Techniques, Shadrach Ibinola May 2024

Yeast Surface Display Of Multiple Heterologous Proteins Via Molecular And Biochemical Processing Techniques, Shadrach Ibinola

Graduate Theses and Dissertations

The arming of yeast cell wall, also known as yeast surface display, is an effective technology for expressing target proteins extracellularly. It has been shown to provide bioengineered yeast with qualities that are not known to native yeast such as the ability to survive harsh conditions including high pH and temperature, for example. Furthermore, this technique has been implemented for various applications which include, protein engineering, bioethanol production, bioremediation, vaccine construction, and antibody development. The major mechanisms of yeast surface display exploit agglutination, flocculation, or proteins with internal repeats as the means by which a target (protein) is covalently attached …


Outcome Measures Or Graduation Rates, That Is The Question, Miran Kang May 2024

Outcome Measures Or Graduation Rates, That Is The Question, Miran Kang

Graduate Theses and Dissertations

The study compared the Outcome Measures (OM) to the traditional Graduation Rates (GR) to ascertain if OM portrayed the performance of higher education institutions differently than GR and to determine which of the two metrics aligned better with accountability policy objectives. GR refers to the percentages of first-time, full-time students who obtain a degree or certificate within 150% of the normal time. OM presents the award status of all degree/certificate-seeking undergraduate students on four cohorts: first-time, full-time (FTFT); first-time, part-time (FTPT); non-first-time, full-time (NFTFT); and non-first-time, part-time (NFTPT). OM was a more comprehensive indicator than GR, particularly for 2-year institutions, …


Exploring The Effects Of N,N-Dimethylbiguanide And Ω-3 Pufas On Muscle Stem Cell Differentiation, Enayah Alhshim May 2024

Exploring The Effects Of N,N-Dimethylbiguanide And Ω-3 Pufas On Muscle Stem Cell Differentiation, Enayah Alhshim

Graduate Theses and Dissertations

The impacts of omega-3 (ω-3) fatty acid and metformin hydrochloride (Met-HCl) on muscle stem cells differentiation, mimicking the fetal muscle development under gestational diabetes mellitus (GDM), were investigated. ω-3 fatty acids have been known for their ability to regulate adipogenic transcription factors such as Sterol Regulatory Element-Binding Protien (SREBPs) and Peroxisome Proliferator-Activated Receptors (PPARs). This regulation resulted in gene expression modification for lipid metabolism and adipocyte differentiation, thus preventing excessive fat accumulation. Additionally, emerging evidence suggested that ω-3 fatty acids may also exert direct effects on myogenic processes that influence muscle stem cells proliferation, differentiation, and maturation. Meanwhile, Met-HCl, an …


Determination Of Ileal Digestible Phosphorous Values In Various Inorganic Sources Meat And Bone Meal Sources, Jay Hampton May 2024

Determination Of Ileal Digestible Phosphorous Values In Various Inorganic Sources Meat And Bone Meal Sources, Jay Hampton

Graduate Theses and Dissertations

Concerns around the economic and environmental consequences of suboptimal or excess dietary P levels in broiler diets has led to increased interest in determining ileal P digestibility values for feed ingredients. Therefore, two experiments (EXP) were conducted to determine the apparent (AID) and standardized ileal digestibility (SID) of P in various inorganic phosphates and meat and bone meals (MBM) using the direct method. In both EXP 1 and 2, ileal samples were collected at 22 d post-hatch from birds fed semi-purified diets based on dextrose and corn starch containing test ingredients and one N and P free (NPF) diet for …


The Role Of The Patterning Cascade Model In Human Mandibular Premolar Variation, Molly Militello May 2024

The Role Of The Patterning Cascade Model In Human Mandibular Premolar Variation, Molly Militello

Graduate Theses and Dissertations

Human mandibular premolars represent a morphologically transitional tooth class, possessing a relatively caniniform third premolar (P3) and a more molariform fourth premolar (P4). Marked variation in cusp height and lingual cusp number are characteristics unique to these postcanine teeth. The aim of this study is to determine if human premolar variation aligns with predictions outlined by the patterning cascade model (PCM). The PCM posits that tooth size and enamel knot spacing/surrounding inhibitory fields (approximated by cusp tip positioning) play a role in determining ultimate crown morphology, providing a predictive framework for examining crown variation within and between individuals. While there …


Potential Non-Invasive Detection Of Lesions In Broiler Femur Heads: Application Of The Dxa Imaging System, Alison Ramser, Elizabeth Greene, Robert Wideman, Sami Dridi May 2024

Potential Non-Invasive Detection Of Lesions In Broiler Femur Heads: Application Of The Dxa Imaging System, Alison Ramser, Elizabeth Greene, Robert Wideman, Sami Dridi

Poultry Science Faculty Publications and Presentations

Leg health is a significant economic and welfare concern for the poultry industry. Current methods of detection rely on visual assessment of the legs and gait scores and bone scoring during necropsy for full characterization. Additionally, the current scoring of femurs only examines the external surface of the femoral head. Through the use of the dual-energy X-ray absorptiometry (DXA) imaging system, we show the presence of a necrotic region in the femurs that would otherwise be considered healthy based on the current evaluation procedures. Importantly, these lesions were present in almost 60% (22 of 37) of femurs that scored normal …


Developing Anisotropic Soft Matter As Functional Materials To Interface With Biological Systems, Homa Ghaiedi May 2024

Developing Anisotropic Soft Matter As Functional Materials To Interface With Biological Systems, Homa Ghaiedi

Graduate Theses and Dissertations

Liquid crystals (LCs) constitute a subset of soft matter possessing hybrid characteristics from both liquid and crystalline phases. In this state, the center of masses remains uncorrelated similar to an isotropic phase, while the long axis of molecules aligns in parallel, resulting in molecules exhibiting orientational and positional order, either individually or concurrently. The directional alignment inherent in LCs arises from the asymmetrical shape and structure of the constituent molecules, causing a spontaneous self-assembly into ordered phases. This cooperative molecular behavior manifests distinctive optical features when subjected to cross polarizers. The remarkable sensitivity of LCs to external stimuli, including temperature, …


The Effect Of Gentle Yoga On Average Daily Step Count, Francesca D'Agrosa May 2024

The Effect Of Gentle Yoga On Average Daily Step Count, Francesca D'Agrosa

Graduate Theses and Dissertations

While walking is a widely accessible form of exercise that is highly effective at increasing overall wellness (Kadir et al., 2019; Zhao et al., 2015) and is a recommended form of physical activity for overweight and obese individuals, studies still indicate low step counts and levels of physical activity in people with obesity (Shultz et al., 2011). Sedentary overweight individuals may avoid walking for several reasons, including physiological and/or biomechanical factors that make walking more difficult. This study attempted to explore and address these avoidant behaviors by employing a single-case ABAB reversal design to implement bi-weekly gentle yoga sessions over …


More Than A Monolith: Three Essays On The Diverse Journey Of Immigrant Students And Their Postsecondary Outcomes, Rian Rinaldi Djita May 2024

More Than A Monolith: Three Essays On The Diverse Journey Of Immigrant Students And Their Postsecondary Outcomes, Rian Rinaldi Djita

Graduate Theses and Dissertations

For many years, the United States (U.S.) has been the country with the largest number of immigrants. As a result, policy about immigrant students’ success becomes crucial since it carries not only ethical implications but also economic and societal implications. While there have been other alternatives for students’ success, such as Career and Technical Education (CTE), undeniably, college is still seen as a common pathway to success (e.g., Choi, 2015; Heckman et al., 2018; Turner, 2004). Unfortunately, there are several gaps in the literature on immigrant students’ success and postsecondary outcomes. First, while there is an increasing number of immigrants …


Exploring The Potential Of Electromagnetic-Driven Energy Technologies In Preventing Microbial And Aflatoxin Contamination Of Grains, Abass A. Oduola May 2024

Exploring The Potential Of Electromagnetic-Driven Energy Technologies In Preventing Microbial And Aflatoxin Contamination Of Grains, Abass A. Oduola

Graduate Theses and Dissertations

Electromagnetic-driven energy such as infrared (IR) technology holds great potential in deactivating Aspergillus flavus spores and prevents aflatoxin B1 (AFB1) contamination. Aflatoxins, highly toxic secondary metabolites primarily produced by Aspergillus species within the Flavi section (A. flavus, A. parasiticus, and A. nomius), pose substantial health risks to both humans and animals due to their significant toxicity and carcinogenic properties. Detecting and quantifying the presence and proliferation of these harmful fungi on food materials can be achieved by measuring the concentration of ergosterol. Ergosterol is a sterol compound produced in the cell membranes of fungi during their growth, providing …


Vegetation Management During Establishment Of Native Grasses And Forb Plantings On Roadsides And Prairie Restoration, Rachel Woody-Pumford May 2024

Vegetation Management During Establishment Of Native Grasses And Forb Plantings On Roadsides And Prairie Restoration, Rachel Woody-Pumford

Graduate Theses and Dissertations

North American prairies have been shrinking due to agricultural production, overgrazing, development of cities and towns, and climate change. However, integrated roadside vegetation management (IRVM) creates the opportunity to reestablish prairies along roadsides through planting native grasses and forbs. Utilizing postememergence (POST) herbicides registered for use along rights-of-way has the potential to remove invasive species and create space for newly establishing native grass and forb species. The use of clopyralid, florpyrauxifen-benzyl, metsulfuron, and quinclorac were found to be safe for use in plantings containing big bluestem (Andropogon gerardii Vitman) and butterfly milkweed (Asclepias tuberosa L.). However, florpyrauxifen-benzyl injured and stunted …


A Mixed Methods Exploration Of Interoceptive Awareness In Adults Who Stutter, Hazel Malcolm May 2024

A Mixed Methods Exploration Of Interoceptive Awareness In Adults Who Stutter, Hazel Malcolm

Graduate Theses and Dissertations

Stuttering is commonly described as a disorder of speech fluency characterized by primary speech behaviors that are judged by external observers to be typical of stuttering, including part-word repetitions, prolongations, and blocks (i.e., silent prolongations or postural fixations). Despite wide use in the field of speech-pathology, definitions focusing on these ‘primary’ behaviors have also been criticized as ‘surface’ or ‘perceptual’ definitions that favor the experience of a listener over that of the speaker. Recent qualitative evidence suggests that, when asked, adults who stutter (AWS) instead define stuttering as an internal feeling or awareness of being ‘stuck’ that is surrounded by …


Characterizing The Role Of Chemo-Mechanical Couplings In The Activation Process Of Proteins That Undergo Conformational Changes, Ugochi Isu May 2024

Characterizing The Role Of Chemo-Mechanical Couplings In The Activation Process Of Proteins That Undergo Conformational Changes, Ugochi Isu

Graduate Theses and Dissertations

Proteins are not static entities; rather, they are dynamic macromolecules that undergo conformational changes to perform their biological functions. These structural transitions are often coupled to chemical events such as lipid interactions, or changes in the cellular environment. Understanding the intricate interplay between chemical perturbations and the resulting mechanical response is crucial for elucidating the activation mechanisms of proteins. This dissertation aims to characterize the role of chemo-mechanical couplings in the activation process of two G protein-coupled receptors (GPCRs): Cannabinoid Receptor 1 (CB1) and Metabotropic Glutamate Receptor 1 (mGluR1). We employ molecular dynamics simulations to investigate the conformational landscapes of …


The Expression Of Recombinant Cas9 Proteins In E. Coli Bl21(De3) Strains, Morgan Reese May 2024

The Expression Of Recombinant Cas9 Proteins In E. Coli Bl21(De3) Strains, Morgan Reese

Graduate Theses and Dissertations

Abstract Extensively used for genome editing, CRISPR-Cas9 is a relatively new tool that has made a major impact in the genomic engineering landscape. Due to this, the production of CRISPR proteins that are not commercially available can limit research applications. Here, we present methods for optimizing laboratory scale production of CRISPR proteins including Cas9. The method uses IPTG to induce gene expression of the specified Cas9 and nickel column purification to isolate proteins. CRISPR proteins are validated for purity by SDS-PAGE gel, western blot, and for activity by in vitro digestion. We thoroughly validate and compare the effectiveness of BL21(DE3) …


Genome-Wide Association Study/ Genomic Prediction Of Cowpea Seed Protein And Black Seed Coat Color In Cowpea, Yilin Chen May 2024

Genome-Wide Association Study/ Genomic Prediction Of Cowpea Seed Protein And Black Seed Coat Color In Cowpea, Yilin Chen

Graduate Theses and Dissertations

Cowpea (Vigna unguiculata [L.] Walp) is a crucial crop in many regions, serving as a vital protein source for humans and livestock. Addressing the need to enhance its nutritional quality and make it easier to cultivate cowpeas of specific colors, this study utilized genome-wide association studies (GWAS) to identify markers associated with protein content and seed coat color patterns in cowpea.

In the protein content study, a GWAS was conducted on 161 cowpea accessions using 110,155 high-quality single-nucleotide polymorphisms (SNPs). Seven significant SNP markers were identified, all located at a locus on chromosome 8 associated with the gene Vigun08g039200, enhancing …


Temporal Trends And Dental Metric Variation In The Macaca Sylvanus Lineage, Cristina Stan May 2024

Temporal Trends And Dental Metric Variation In The Macaca Sylvanus Lineage, Cristina Stan

Graduate Theses and Dissertations

The extensive collection of fossil macaques from Europe, spanning from the Late Miocene to the Late Pleistocene period, is believed to be of the species Macaca sylvanus. However, there has been a prolonged discussion regarding the classification of these specimens into a single taxonomic group as the existing dental sample exhibits a large amount of morphological and metric variation. Specifically, researchers have attempted to identify multiple subspecies based on chronological data of the paleontological locality and, secondly, based on dental metric variation. In this study, I assess temporal trends in the fossil record of Macaca sylvanus and compare overall variation …


Turfgrass Soil Surfactants: Examining Active Ingredients, Application Strategies, And The Structure–Function Relationship In Sand-Based Putting Greens, Daniel O'Brien May 2024

Turfgrass Soil Surfactants: Examining Active Ingredients, Application Strategies, And The Structure–Function Relationship In Sand-Based Putting Greens, Daniel O'Brien

Graduate Theses and Dissertations

Soil surfactants, commonly referred to as wetting agents, are a leading water management strategy for golf courses. Non-ionic block copolymers are the most common type of turfgrass soil surfactant. However, differences in the registration process and labeling requirements allow soil surfactants to enter the marketplace accompanied by far-less data compared to other products used on golf courses. This has led to considerable confusion among golf course superintendents. Three primary sources of confusion are: (i) the widely-used marketing terminology of “penetrants” and “retainers” to classify wetting agents; (ii) active ingredients which in some cases are not disclosed at all; and (iii) …


Evaluation Of The Effect Of A Commercial Lippia Origanoides Essential Oil Extract On Salmonella Serovar Enteritidis As A Natural Alternative To Antibiotics In The Poultry Industry, Abdiel Atencio May 2024

Evaluation Of The Effect Of A Commercial Lippia Origanoides Essential Oil Extract On Salmonella Serovar Enteritidis As A Natural Alternative To Antibiotics In The Poultry Industry, Abdiel Atencio

Graduate Theses and Dissertations

The purpose of the present research was to evaluate the bactericidal activity of a microencapsulated Lippia origanoides essential oils (LOEOs) against Salmonella Enteritidis (SE) in an in vitro crop assay and in a prophylactic broiler chicken model using three low doses of the product: 75 ppm, 150 ppm and 300 ppm. Two trials of each assay were conducted. Day-of-hatch male Cobb-Vantress broiler chickens were randomly allotted to one of four groups: 1) positive control group; 2) 75 ppm LOEOs group; 3) 150 ppm LOEOs group; 4) 300 LOEOs group. Chicks were fed and watered ad libitum in heated brooder batteries …


Two Studies: Aromatization-Driven Ring Opening Functionalization Of Unstrained Cycloalkanones Through Visible Light Catalysis, And Synthesis Of Amino Endoperoxides Using Self-Doped Titanium Dioxide (Ti3+@Tio2) As A Photocatalyst, Enoch Kudoahor May 2024

Two Studies: Aromatization-Driven Ring Opening Functionalization Of Unstrained Cycloalkanones Through Visible Light Catalysis, And Synthesis Of Amino Endoperoxides Using Self-Doped Titanium Dioxide (Ti3+@Tio2) As A Photocatalyst, Enoch Kudoahor

Graduate Theses and Dissertations

The pharmaceutical industry has been focused on discovering new innovative drugs over the last decade, but the syntheses are either inefficient or the approach to environmental sustainability raises significant concerns. Photochemistry and photocatalysis have found widespread applications in organic synthesis as a result of this pressing issue. Our role as organic chemists is to improve environmental quality by creating a "greener" world through the development of efficient synthetic methods and strategies. Solar energy is now one of the most abundant and renewable natural resources. The emergence of environmental sustainability concerns has led to the development of new techniques for harnessing …


Catchment-Scale Thawing And Greening Decreases Long-Term Nitrogen Export In Ne Greenland, Shannon L. Speir, Jennifer L. Tank, Ada Pastor, Marc F. Muller, Mikhail Mastepanov, Tenna Riis May 2024

Catchment-Scale Thawing And Greening Decreases Long-Term Nitrogen Export In Ne Greenland, Shannon L. Speir, Jennifer L. Tank, Ada Pastor, Marc F. Muller, Mikhail Mastepanov, Tenna Riis

Crop, Soil and Environmental Sciences Faculty Publications and Presentations

Climate change is expected to alter nitrogen (N) export from Arctic rivers, with potential implications for fragile coastal ecosystems and fisheries. Yet, the directionality of change is poorly understood, as increased mobilization of N in a 'thawing' Arctic is countered by higher rates of vegetative uptake in a 'greening' Arctic, particularly in the understudied region of Greenland. We use an unprecedented dataset of long-term (n = 18 years) river chemistry, streamflow, and catchment-scale changes in snow and vegetation to document changing riverine N loss in Greenland. We documented decreasing inorganic and organic N loads, linked to decreasing snow stores, …


Dispersal Movement And Overwintering Ecology Of A Cryptic Migratory Forest Owl, Mitchell Lee Pruitt May 2024

Dispersal Movement And Overwintering Ecology Of A Cryptic Migratory Forest Owl, Mitchell Lee Pruitt

Graduate Theses and Dissertations

Understanding species’ distributions and how a species uses its environment is a vital aspect of ecology and important for the development and implementation of conservation planning. In migratory species, with distinct breeding and nonbreeding ranges, understanding distributions is a complex endeavor. Nevertheless, evaluating movement behavior by linking seasonal distributions and identifying source areas is vital for understanding a species’ full annual cycle ecology. Understanding distributions is particularly important for predators, like birds of prey, that can exert top-down effects on community structure and ecosystem function through their influence on prey populations. Among raptors, owls are severely understudied in large part …


Affinity-Enhanced Microdialysis Using Covalent Organic Frameworks (Cofs) Applied To Various Non-Steroidal Anti-Inflammatory Drugs (Nsaids) And Their Metabolites, Kehinde Adedeji Olubanjo May 2024

Affinity-Enhanced Microdialysis Using Covalent Organic Frameworks (Cofs) Applied To Various Non-Steroidal Anti-Inflammatory Drugs (Nsaids) And Their Metabolites, Kehinde Adedeji Olubanjo

Graduate Theses and Dissertations

Microdialysis is a valuable tool in neurosciences and pharmaceutical sciences, aiding research in drug-related areas. However, it faces a notable limitation in sampling hydrophobic analytes due to their adherence to the probe materials brought about by non-specific adsorption, thereby reducing relative recovery or overall extraction. In this work, two affinity agents, polydimethylsiloxane (PDMS) beads suspended in sodium dodecyl sulfate (SDS) surfactant and covalent organic frameworks I(COFs) were employed as affinity agents in microdialysis for the extraction of hydrophobic drugs. When PDMS beads were employed as affinity agents, at the flow rate of 1 µL/min the relative recovery of both the …