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Full-Text Articles in Life Sciences

Integrating Innovative Sensing And Ground Measurements For Forage Mass Estimation In Rye Pasture, Pedro Henrique Jota Fernandes Dec 2025

Integrating Innovative Sensing And Ground Measurements For Forage Mass Estimation In Rye Pasture, Pedro Henrique Jota Fernandes

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

The United States beef industry relies on forages to provide up to 80% of total lifetime dry matter intake, making accurate forage mass estimation essential for determining stocking rates, improving grazing efficiency, and supporting economic sustainability. Traditional methods to quantify forage mass, however, are time-consuming and labor-intensive. This thesis presents research efforts to achieve accurate forage mass estimation in cereal rye pasture by integrating novel sensing technologies.

Chapter 1 reviews the importance and evolution of forage mass estimation methods, from destructive clipping to indirect approaches based on canopy measurements. It then introduces remote sensing, from proximal tools to drone- and …


Investigation Of Changes In Exotic Bird Serum Vitamin D Levels Between Indoor And Outdoor Housing, Alexander J. Marley Dec 2025

Investigation Of Changes In Exotic Bird Serum Vitamin D Levels Between Indoor And Outdoor Housing, Alexander J. Marley

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

Vitamin D is a fat-soluble vitamin that is directly related to sunlight and is involved in multiple physiological processes including calcium metabolism, feather quality, and chick development. Most vertebrate species are capable of both absorption of exogenous vitamin D and internal synthesis of vitamin D, with vitamin D3 (cholecalciferol), being more accessible and bioactive in bird species. In exotic bird species, dietary requirements for vitamin D3 are largely unknown, and the ability to maintain adequate serum concentrations of vitamin D3 metabolites without direct sunlight exposure also requires evaluation. Concerns arise in situations where individuals may be housed indoors for extended …


Establishing Procedures For Primary Human Myoblast Cell Culture, Erica Duffy Dec 2025

Establishing Procedures For Primary Human Myoblast Cell Culture, Erica Duffy

Biomedical Engineering

Peripheral Artery Disease (PAD) affects an estimated 200 million people worldwide and is the leading cause of amputation in the United States. PAD is characterized by atherosclerotic narrowing of arteries, resulting in ischemia from reduced blood flow to distal tissues. Although surgical and percutaneous interventions can restore perfusion, fewer than 50% of patients experience sustained benefit, highlighting the need for alternative therapeutic strategies. One promising approach is promoting arteriogenesis, the growth and outward remodeling of pre-existing collateral vessels that improve blood flow around the occluded arteries. Arteriogenesis is regulated by regenerative, M2-polarized macrophages, making macrophage polarization a key therapeutic target. …


Effect Of Planting Date, Insecticide Efficacy, And Hail Injury On Soybean Gall Midge (Resseliella Maxima Gagné) Infestation In Soybean, Natasha Hiromi Umezu Dec 2025

Effect Of Planting Date, Insecticide Efficacy, And Hail Injury On Soybean Gall Midge (Resseliella Maxima Gagné) Infestation In Soybean, Natasha Hiromi Umezu

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

Resseliella maxima Gagné (Diptera: Cecidomyiidae) is a recently described and economically significant pest of soybean (Glycine max (L.) Merr.) in the Midwestern United States. Since its identification in 2019, this species has become widespread and is now associated with substantial yield losses in parts of the region. Prior to its formal description, orange larvae were observed in soybean associated with plants damaged by hail, suggesting that plant injury may influence infestation. Given the pest’s economic importance, understanding the role of hail injury and developing effective, integrated management strategies are critical for mitigating its impact.

Field studies were conducted to …


Infochemicals For The Management Of Thysanoptera, Nanadagopal Bakthavatsalam, Kesavan Subaharan, Anjenappa Raghavendra, Sevgan Subramaniam Dec 2025

Infochemicals For The Management Of Thysanoptera, Nanadagopal Bakthavatsalam, Kesavan Subaharan, Anjenappa Raghavendra, Sevgan Subramaniam

All Peer-Reviewed Publications

Infochemicals, classified as pheromone, kairomone, allomone, synomone and apneumone, play significant role in insect communication. Unlike Lepidoptera, Thysanoptera utilize male produced aggregation pheromone for their communication. Neryl (S)-2-methybutanoate, (R) lavandulyl acetate, (+) R-lavandulyl 3 methyl-butenoate, dodecyl acetate and tetradecyl acetate are the compounds identified as aggregation pheromones for several species. Pheromone lures placed in blue or yellow or white sticky traps are effective in capturing adults of Frankliniella, Thrips, Megalurothips and Odonothrips. Decyl acetate and dodecyl acetate along with other volatile chemicals have been identified as alarm pheromones for many Thysanoptera. Push-Pull technology using alarm pheromone and aggregation pheromone or …


When Thermal Risk Indices Work And When They Don't: A Case Study Of Two Maize Insect Pests, Komi Mensah Agboka, Frank Thomas Ndjomatchoua, Luca Rossini, Ritter A. Guimapi, Elfatih M. Abdel-Rahman Dec 2025

When Thermal Risk Indices Work And When They Don't: A Case Study Of Two Maize Insect Pests, Komi Mensah Agboka, Frank Thomas Ndjomatchoua, Luca Rossini, Ritter A. Guimapi, Elfatih M. Abdel-Rahman

All Peer-Reviewed Publications

The biological life cycle of terrestrial arthropods, using temperature as the primary driving factor has a large interest for insect pests in agriculture, forestry, urban ecosystems, as constitutes the basics for the development of mathematical models for decision making. A recent study proposed a physiologically-based risk index (RI) which finds large applications in the definition of risk maps; however, further case studies are needed to better explore its strengths and limitations. This study aims to extend this knowledge by presenting an application of the RI on two economically significant pests: the fall armyworm Spodoptera frugiperda and the stem borer Busseola …


Fungicidal Management Of Spring Dead Spot Using Improved Modeling And Application Strategies, Michael Vincent Battaglia Dec 2025

Fungicidal Management Of Spring Dead Spot Using Improved Modeling And Application Strategies, Michael Vincent Battaglia

Graduate Theses and Dissertations

Spring dead spot (SDS) is a destructive disease of bermudagrass (Cynodon Rich. spp.) in parts of the world that experience winter dormancy. Fungicides are often necessary to properly manage SDS, and significant research has been conducted to improve fungicidal effectiveness. Several studies were conducted with the objectives of improving fungicide application timing, method of fungicide application, and long-term fungicidal efficiency. In the fungicide application study, a cooling degree-day (CDD) model based on soil temperatures was developed. The CDD model showed that isofetamid was highly effective against SDS during a wide application window in autumn, while tebuconazole was inconsistently effective and …


The Influence Of Tert-Butylhydroquinone (Tbhq) On Acod1/Irg1-Driven Inflammatory Pathways, Alyssa M. Whisel Dec 2025

The Influence Of Tert-Butylhydroquinone (Tbhq) On Acod1/Irg1-Driven Inflammatory Pathways, Alyssa M. Whisel

All Dissertations

The demand for processed foods has led to increased use of synthetic phenolic antioxidants (SPAs), notably tert-butylhydroquinone (TBHQ), to inhibit lipid oxidation and prolong shelf life. While TBHQ is deemed safe at regulated levels, concerns arise from studies indicating potential adverse effects such as oxidative stress, genotoxicity, and impaired immune function. To investigate TBHQ's immunomodulatory effects, RAW 264.7 murine macrophages were pre-treated with TBHQ and subsequently stimulated with lipopolysaccharide (LPS) or polyinosinic-polycytidylic acid (poly I:C, PIC) to simulate bacterial or viral challenges. Results demonstrated that TBHQ at high non-cytotoxic doses reduced nitric oxide and IL-10 production while promoting phagocytosis and …


Drivers Of Faunal Communities In Isolated Wetlands: Local And Landscape Determinants Of Assemblages, Joshua Holbrook Dec 2025

Drivers Of Faunal Communities In Isolated Wetlands: Local And Landscape Determinants Of Assemblages, Joshua Holbrook

All Dissertations

Ecological interactions such as predation are vital to shaping the distribution of organisms. For interactions to occur, organisms must undertake movement, such as dispersal, that places them in proximity to the organisms with which they may interact. Geographically isolated wetlands (GIW) are productive and biodiverse ecosystems, but little is known on broad geographic scales about the determinants of their fauna. Fishes have difficulty colonizing GIW, whereas amphibians and macroinvertebrates are adept overland dispersers – though they may be sensitive to top-down control by fishes. To better understand these phenomena, I sampled 10-20 wetlands each at nine regions in North and …


Exploring Glycosomes As Therapeutic Targets For Trypanosoma Brucei, Sabrina Sutton Pizarro Dec 2025

Exploring Glycosomes As Therapeutic Targets For Trypanosoma Brucei, Sabrina Sutton Pizarro

All Dissertations

Trypanosoma brucei is a protozoan parasite which causes human African trypanosomiasis and the livestock wasting disease, nagana. These parasites have highly specialized peroxisomes, called glycosomes, which house a variety of essential metabolic pathways, including glycolysis. Glycolysis is the sole means of energy production in the infective life stage of T. brucei making glycosomes and the glycolytic pathway promising targets for therapeutic strategies. In this work, we have studied the glycosome as a therapeutic target from multiple perspectives. The first portion of this work addresses drug trafficking. The efficacy of small-molecule inhibitors of glycosomal enzymes is restricted by the rate of …


Avaren-Fc's Effects On Lymphoma Cells., Jacob Hahn Dec 2025

Avaren-Fc's Effects On Lymphoma Cells., Jacob Hahn

Electronic Theses and Dissertations

This thesis investigates the therapeutic potential of Avaren-Fc (AvFc), a novel lectin fusion protein that integrates the Fc region of human IgG1 with the engineered lectin Avaren, specifically targeting lymphoma. The study delineates the in vitro binding capabilities of Avaren-Fc with a human B-cell lymphoma cell line, a canine B-cell lymphoma cell line, healthy canine peripheral blood mononuclear cells (PBMCs), and healthy human PBMCs. AvFc was shown to exhibit significant binding to human lymphoma cells. Furthermore, the direct cytotoxicity of Avaren-Fc against canine lymphoma cells, canine lymphoma cells and healthy canine PBMCs was assessed. It was found that there is …


Enzymatic Depletion Of Adenosine To Potentiate Cancer Immunotherapy., Omar Sadi Sarkar Dec 2025

Enzymatic Depletion Of Adenosine To Potentiate Cancer Immunotherapy., Omar Sadi Sarkar

Electronic Theses and Dissertations

Immune checkpoint blockade (ICB) therapies have revolutionized cancer treatment, but many patients still do not respond well. To improve therapeutic outcomes, chemotherapy is often combined with immunotherapy, as chemotherapy is known to promote immunogenicity. However, many patients develop resistance to this combination therapy, and the reasons behind it are not fully understood. In this study, we explored how platinum-based chemotherapy, specifically cisplatin, affects tumor signaling to create an immunosuppressive tumor microenvironment (TME). We found cisplatin triggers ataxia telangiectasia mutated (ATM)-mediated DNA damage signaling and induces higher expression of prostaglandin E₂ (PGE₂) via a cyclooxygenase-2 (COX-2) mediated pathway. We speculate DNA …


Exposure To Pm2.5 And Aging., Daniel Chris Gomes Dec 2025

Exposure To Pm2.5 And Aging., Daniel Chris Gomes

Electronic Theses and Dissertations

Inhalation of fine airborne particulate matter (PM2.5) is an environmental risk factor for numerous health disorders, including cardiovascular diseases (CVD). While several studies have shown that PM2.5 exposure can induce oxidative stress, DNA damage, and inflammation, the underlying mechanisms that translate these effects into systemic pathology remain poorly understood. Some recent studies have shown that PM2.5 exposure can lead to telomere shortening in leukocytes, but the generality of this outcome and contribution to endothelial dysfunction has not yet been fully explored. We hypothesized that PM2.5inhalation accelerates cellular aging and senescence in both circulating peripheral …


Integration And Modulation Of Visual Signals In Dorsal Thalamus., James Whitley Dec 2025

Integration And Modulation Of Visual Signals In Dorsal Thalamus., James Whitley

Electronic Theses and Dissertations

The visual thalamus is influenced by a diverse array of cortical and subcortical inputs that shape how information is transmitted to cortex. Using a variety of anatomical, optogenetic, and in vitro physiological techniques I investigated the differential impacts of modulation and integration of first and higher-order thalamic nuclei, while relying on influential concepts on the general organization of thalamic nuclei. In the first data chapter, I determined how GABAergic pretectum (PT) projections to the dorsal lateral geniculate nucleus (dLGN) and visual thalamic reticular nucleus (vTRN) can influence retinogeniculate signal transfer. We found that the PT provides over 75% of the …


Characterizing Hexavalent Chromium Neurotoxicity Across Laboratory Models., Samuel Thomas Vielee Dec 2025

Characterizing Hexavalent Chromium Neurotoxicity Across Laboratory Models., Samuel Thomas Vielee

Electronic Theses and Dissertations

Hexavalent chromium [Cr(VI)] is a ubiquitous environmental pollutant and potent toxicant. Exposure to Cr(VI) in drinking water is primarily associated with cancers, inflammation, and hepatotoxicity; however, recent studies have identified Cr(VI) as a neurotoxicant in rodent and cell culture models. The literature suggest chromium accumulates in the brain, induces widespread neurodegeneration, and alters rodent behaviors. Despite these data, we lack a detailed and consistent assessments of Cr(VI) neurotoxicity across models, and interactions between aging and Cr(VI) neurotoxicity are not reported in the literature. In this dissertation, we characterize Cr(VI) neurotoxicity across 3 laboratory models: Sprague-Dawley rats, Caenorhabditis elegans, and …


The Ecology Of Arthropod Rain In A Tropical Forest., Andrew Robert Seiler Dec 2025

The Ecology Of Arthropod Rain In A Tropical Forest., Andrew Robert Seiler

Electronic Theses and Dissertations

Tropical forests are structured by complex vertical linkages and nutrient exchanges between canopy and understory habitats. These linkages include the downward flux of organisms, the movement of canopy fauna, and the recycling of nutrients through litter and organic matter deposition. This dissertation investigates arthropod rain and its role in connecting the canopy and forest floor processes in a lowland tropical forest in Panama. Chapter 2 quantifies “arthropod rain”, the fall of canopy arthropods into the understory. Using pan and pole traps, I measured the composition, abundance, and biomass of arthropods falling from the canopy and assessed environmental drivers of the …


Assessing Native Tallgrass Prairie Species As Main Roadside Vegetation In Arkansas, Sarah Paschal Dec 2025

Assessing Native Tallgrass Prairie Species As Main Roadside Vegetation In Arkansas, Sarah Paschal

Graduate Theses and Dissertations

Tallgrass prairies are among the most endangered ecosystems in North America, with Arkansas having lost over 99% of its native grasslands. This research evaluated the potential for using native tallgrass prairie species in Arkansas roadside vegetation. Two field experiments were conducted from 2022 to 2024. The first assessed seven native seed mixtures at three roadside locations (Clarksville, Huntsville, and Newport). Seed mixture composition significantly influenced establishment outcomes, with early-establishing forbs such as black-eyed Susan, partridge pea, and Illinois bundleflower performing well, though establishment varied by location. A second trial compared planting date (Autumn, Winter, Spring) and planting method (broadcast, drill …


Hyperspectral Indicators And Characterization Of Glyphosate-Induced Stress In Common Lambsquarters (Chenopodium Album L.), Mario Andrés Soto Valencia Dec 2025

Hyperspectral Indicators And Characterization Of Glyphosate-Induced Stress In Common Lambsquarters (Chenopodium Album L.), Mario Andrés Soto Valencia

Graduate Theses and Dissertations

Hyperspectral sensing enables detection of herbicide stress in weeds, but practical use requires strategies for redundancy control, rating variability management, and evaluator bias mitigation. This thesis evaluates common lambsquarters (Chenopodium album) under glyphosate exposure, aiming to identify key wavelengths, construct vegetation indices, and improve injury modeling. Greenhouse experiments used dimensionality reduction methods (principal component analysis, Relief F, Bayesian discriminant analysis) to isolate 34 unique wavelengths from about 3,200 bands. Calibration data were collected 14 days after treatment (DAT) to support wavelength selection and model development, while data from 27 DAT were used for independent validation. Class comparisons across six statistically …


Establishment Of Native Warm-Season Forages Using Organic Practices, Kolten Ray Wright Dec 2025

Establishment Of Native Warm-Season Forages Using Organic Practices, Kolten Ray Wright

Graduate Theses and Dissertations

Abstract Grassland agriculture is seen as a particularly sustainable form of agriculture. Many opportunities are known to use organic production methods or incorporate native warm-season grasses (NWSG) to accomplish both production goals and environmental or social outcomes. Environmental concerns have led some practitioners to question the use of organic methods to establish NWSG. As limited work has been accomplished in the northern bermudagrass belt, this project sought to compare organic establishment strategies for common NWSG species. A field trial conducted at the USDA ARS Dale Bumpers Small Farms Research Center in Booneville, AR found that NWSG establishment success in the …


Effect Of Peracetic Acid Dip Frequency On The Quality And Functional Properties Of Non-Marinated And Marinated Broiler Tenderloins, Joaquin Jose Esquivel Vergara Dec 2025

Effect Of Peracetic Acid Dip Frequency On The Quality And Functional Properties Of Non-Marinated And Marinated Broiler Tenderloins, Joaquin Jose Esquivel Vergara

Graduate Theses and Dissertations

The poultry industry continues to balance the need for effective antimicrobial interventions with the preservation of meat quality. Among the most widely used antimicrobial agents, peracetic acid (PAA) has proven effective for reducing foodborne pathogens in poultry products. However, excessive or repeated exposure to PAA can influence meat functionality by altering protein structure, color, and water-holding capacity. Therefore, the broad objective of this study was to evaluate the effect of PAA dip frequency and post-treatment marination timing on the physicochemical and functional quality of broiler tenderloins (Pectoralis minor), in order to provide processing insights that optimize both microbial safety and …


Broiler Responsiveness To Dietary Amino Acid Density In A Commercial Setting, Virginia Slick Dec 2025

Broiler Responsiveness To Dietary Amino Acid Density In A Commercial Setting, Virginia Slick

Graduate Theses and Dissertations

The majority of research assessing the amino acid responsiveness in broilers has been conducted in experimental designs utilizing pens that contain 12 to 25 birds with high replication. While this trial design is beneficial as a way to perform high replications with multiple treatments in a way that is both economically and spatially feasible, it may not accurately translate to a rearing environment more similar to that of commercial open floor housing. This research was conducted to determine if the effects of lysine driven amino acid density diets that have been found in the traditional floor pen setting correlate to …


Maximizing Horizontal Transmission Through Mating: Increased Mating Frequency And Mating Competitiveness Associated With Microsporidia Mb-Infected Anopheles Arabiensis Males, Tracy Maina, Aclaine Shisia, Joseph Gichuhi, Joel L. Bargul, Jeremy K. Herren, Tullu Bukhari Dec 2025

Maximizing Horizontal Transmission Through Mating: Increased Mating Frequency And Mating Competitiveness Associated With Microsporidia Mb-Infected Anopheles Arabiensis Males, Tracy Maina, Aclaine Shisia, Joseph Gichuhi, Joel L. Bargul, Jeremy K. Herren, Tullu Bukhari

All Peer-Reviewed Publications

Background: Microsporidia MB is a naturally occurring symbiont in Anopheles arabiensis mosquitoes that inhibits the development of Plasmodium. It is transmitted both vertically and horizontally, enabling its spread within mosquito populations. Currently, mating is the only known mechanism for horizontal transmission. Understanding the factors that influence Microsporidia MB transmission during mating is crucial for developing a malaria transmission-blocking strategy based on this symbiont. Methods: The effect of mosquito age on Microsporidia MB transmission was determined through mating bioassays between infected and uninfected Anopheles arabiensis males and females in three age groups: 3–4 days, 7–8 days, and 10–11 days. Mating bioassays …


The Effects Of Green Orientation And Technological Agility On Sustainable Competitive Advantage Under Environmental Uncertainty: Organizational Agility As A Pathway, Sahilali Saiyed, Vimal Kumar, Abdul Waaje, Adi Prasetyo Tedjakusuma Dec 2025

The Effects Of Green Orientation And Technological Agility On Sustainable Competitive Advantage Under Environmental Uncertainty: Organizational Agility As A Pathway, Sahilali Saiyed, Vimal Kumar, Abdul Waaje, Adi Prasetyo Tedjakusuma

Michigan Tech Publications

Despite the strengthened efforts on sustainability and technological activities by firms, the existing literature lacks a clear picture regarding how green orientation (GO) and technological agility (TAG) can be transformed into sustainable competitive advantage (SCA) and at what time the conversion process may be most efficient. This paper conceptualizes organizational agility (OGA) based on the resource-based view (RBV) and dynamic capabilities theory (DCT) and hypothesizes that GO and TAG indirectly affect SCA with the mediating impact of environmental uncertainty (ELU). A moderated-mediation model was tested based on a sample of 200 managers (HR, marketing, accounting/finance, quality control, R&D) of auto-parts …


Population Genomics Of Pacific Herring Spawning Aggregations In The Eastern Bering Sea, Sydney A. Almgren Dec 2025

Population Genomics Of Pacific Herring Spawning Aggregations In The Eastern Bering Sea, Sydney A. Almgren

Fisheries

Pacific herring (Clupea pallasii) is a critical forage fish to the marine environment, economy, and culture of Alaska. However, despite the importance of Pacific herring in Alaska and throughout the North Pacific, knowledge gaps exist for foundational genomic characteristics of the species, including genetic population structure and the basis of genetic sex determination. In this thesis, I addressed these knowledge gaps using low coverage, whole genome sequencing. I assessed population structure and genetic diversity across seven sampling sites and found three genetic populations: Unalaska, the farthest south sampling location, Kotzebue, the farthest north, and a third group unassociated with geographic …


Microinjection, Gene Knockdown, And Crispr-Mediated Gene Knock-In In The Hard Coral, Astrangia Poculata, Jacob F. Warner, Ryan Besemer, Alicia Schickle, Erin Borbee, Isabella V. Changsut, Koty H. Sharp, Leslie S. Babonis Dec 2025

Microinjection, Gene Knockdown, And Crispr-Mediated Gene Knock-In In The Hard Coral, Astrangia Poculata, Jacob F. Warner, Ryan Besemer, Alicia Schickle, Erin Borbee, Isabella V. Changsut, Koty H. Sharp, Leslie S. Babonis

Arts & Sciences Faculty Publications

Cnidarians have become valuable models for understanding many aspects of developmental biology including the evolution of body plan diversity, novel cell type specification, and regeneration. Most of our understanding of gene function during early development in cnidarians comes from a small number of experimental systems including Hydra and the sea anemone, Nematostella vectensis. Few molecular tools have been developed for use in hard corals, limiting our understanding of this diverse and ecologically important clade. Here, we report the development of a suite of tools for manipulating and analyzing gene expression during early development in the northern star coral, Astrangia poculata. …


Gene Expression Reveals The Pancreas Of Aselli As A Critical Organ For Plasma Cell Differentiation In The Eurasian Common Shrew, William R. Thomas, Cecilia Baldoni, Tanya M. Lama, Yuanyuan Zeng, Angelique P. Corthals, Dominik Von Elverfeldt, John Nieland, Dina K.N. Dechmann, Liliana M. Dávalos Dec 2025

Gene Expression Reveals The Pancreas Of Aselli As A Critical Organ For Plasma Cell Differentiation In The Eurasian Common Shrew, William R. Thomas, Cecilia Baldoni, Tanya M. Lama, Yuanyuan Zeng, Angelique P. Corthals, Dominik Von Elverfeldt, John Nieland, Dina K.N. Dechmann, Liliana M. Dávalos

Biological Sciences: Faculty Publications

Background: Almost all mammals rely on the thymus and bone marrow to generate and differentiate B and T cells essential for adaptive immunity. A few members of the family Soricidae, or true shrews within Eulipotyphla, have also evolved an enlarged pancreas of Aselli, a kidney-sized organ hypothesized to serve this primary immune role, and whose gene expression profile is unknown. Results: Here we introduce transcriptomes of juvenile Eurasian common shrews (Sorex araneus, family Soricidae) pancreas of Aselli. We compare these to those of the shrew spleen and chick bursa of Fabricius, an analogous, bird-specific organ, and explore differential expression overlaps …


Tracing The Journey Of Dissolved Organic Matter: From Leaf Litter Photodegradation To Microbial Processing In Tropical Streams, Samantha Nicole Sullivan Dec 2025

Tracing The Journey Of Dissolved Organic Matter: From Leaf Litter Photodegradation To Microbial Processing In Tropical Streams, Samantha Nicole Sullivan

Chemistry & Biochemistry Theses & Dissertations

Dissolved organic matter (DOM) is a major reservoir of organic carbon in aquatic ecosystems and plays a central role in global carbon cycling through its transformation and remineralization to carbon dioxide (CO₂). As DOM moves from terrestrial environments into streams and rivers, its chemical composition is altered by a combination of microbial and photochemical oxidation processes that regulate both its reactivity and its persistence during transport. However, the molecular mechanisms governing these oxidative transitions, particularly in tropical ecosystems characterized by strong hydrologic seasonality and substantial inputs of plant-derived material, remain insufficiently resolved. This dissertation integrates ultrahigh-resolution mass spectrometry, optical characterization, …


Margalefidinium Polykrikoides Group Iii Va, Usa Strain Growth And Sac-Like Pellicle Cyst Dynamics, Eduardo Pérez Vega Dec 2025

Margalefidinium Polykrikoides Group Iii Va, Usa Strain Growth And Sac-Like Pellicle Cyst Dynamics, Eduardo Pérez Vega

OES Theses and Dissertations

Margalefidinium polykrikoides is a harmful cosmopolitan dinoflagellate that blooms in coastal waters. The effect of temperature and salinity on the growth of M. polykrikoides VA strain was examined using microscopy and growth models. M. polykrikoides Group III VA strain grew better at warmer temperatures and lower salinities than M. polykrikoides Group III NY strain, Group I Korea strain, and Japan strain (unknown group). Modelers need to use the temperature and salinity growth responses from M. polykrikoides Group III VA strain to better simulate and predict M. polykrikoides blooms in the Chesapeake Bay.

Dinoflagellates produce cysts as a strategy to withstand …


Expression, Purification And Characterization Of Full Length Tdp-43, Danya Abouzaid Dec 2025

Expression, Purification And Characterization Of Full Length Tdp-43, Danya Abouzaid

Honors Theses

TAR DNA-binding protein 43 (TDP-43) is a 43 kDa RNA-binding protein linked to several neurodegenerative diseases, including amyotrophic lateral sclerosis (ALS), frontotemporal dementia (FTD), and Alzheimer’s disease. 5-7,28,30,33 Studying full-length TDP-43 has been difficult because of its intrinsic instability and tendency to aggregate.19,25,28,33,36 In this study, we focused on overcoming the difficulties to express full-length TDP-43 in E. coli recombinantly. We focused on expressing full-length TDP-43 as a fusion construct with a maltose-binding protein (MBP) to improve solubility and stability. Our strategy was to purify TDP-43-MBP fusion and make biomolecular condensates with RNA before cleaving the tag with thrombin protease. …


Investigating The Cardiovascular And Autonomic Responses To Energy Drink Consumption: The Role Of Energy And Calorie Content, Sophia Schmidt Dec 2025

Investigating The Cardiovascular And Autonomic Responses To Energy Drink Consumption: The Role Of Energy And Calorie Content, Sophia Schmidt

Honors Theses

Energy drinks (EDs) are among the most consumed functional beverages, often marketed to enhance focus, alertness, and physical performance. Despite their popularity, the combined cardiovascular and autonomic effects of caffeine and sugar during exercise remain poorly understood. The purpose of this study was to examine the acute cardiovascular, metabolic, and autonomic responses to sugar-sweetened (ED-S), non-nutritive sweetened (ED-NNS), and placebo beverages during submaximal cycling in healthy young males.

Nine male participants (age 22.2 ± 2.4 yrs; BMI 26.2 ± 2.9 kg/m²) completed three experimental visits in a randomized, repeated-measures design. Each visit involved ingestion of one drink (ED-S, ED-NNS, or …