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The Evolution Of A Response To Smoke Within The Arthropoda, Adam Miles Aug 2024

The Evolution Of A Response To Smoke Within The Arthropoda, Adam Miles

Masters Theses & Specialist Projects

Many animals have a survival instinct to flee in response to fire, but do they respond to smoke alone? Many arthropods respond to fire or smoke by moving in the opposite direction (a negative taxis) to obtain shelter. At the species level, taxa that have adapted a behavioral response to fire increase their fitness. This response behavior has been observed in many terrestrial arthropods. Still, the behavior is currently unknown for marine, aquatic, or cave arthropods, which are atypically exposed to smoke or fire. This project assesses how often behavioral adaptation to smoke avoidance may have evolved within Arthropoda. Twenty-two …


Proceedings Of The 2024 Berry Summer Thesis Institute, University Of Dayton. University Honors Program, Magdelyn Stewart, Noah Clemens, Sarah Theewis, Henry Salisbury, Kevin Johnston, Adin Stoller, Meggie Bailey, Erin T. Flaherty, Adelyn Hughes, Marc Nya Aug 2024

Proceedings Of The 2024 Berry Summer Thesis Institute, University Of Dayton. University Honors Program, Magdelyn Stewart, Noah Clemens, Sarah Theewis, Henry Salisbury, Kevin Johnston, Adin Stoller, Meggie Bailey, Erin T. Flaherty, Adelyn Hughes, Marc Nya

Proceedings of the Berry Summer Thesis Institute (2013-Present)

Thanks to a gift from the Berry Family Foundation and the Berry family, the University Honors Program launched the Berry Summer Thesis Institute in 2012. The institute introduces students in the University Honors Program to intensive research, scholarship opportunities and professional development. Each student pursues a 12-week summer thesis research project under the guidance of a UD faculty mentor. This contains the product of the students' research.

Contents:

Testing the Influence of Lithology and Ice Sheet Dynamics on Waterfall Formation in Hocking Hills State Park // Magdelyn Stewart

Step-Rate Manipulation for Improved Performance: A Review// Noah Clemens

Alfred Rosenberg: An …


Characterizing Oxylipins In Human Milk Extracellular Vesicles, Priscila Herrera Aug 2024

Characterizing Oxylipins In Human Milk Extracellular Vesicles, Priscila Herrera

Food Science (MS) Theses

Extracellular vesicles (EVs) are non-replicating lipid bilayer membrane-bound particle formed by a parent cell and secreted into the extracellular environment. EVs in human milk are bioavailable and influence physiologic pathways that may contribute to newborn growth and development. There is interest in the oxylipin content of EVs that may contribute to the bioavailability of EVs. This research aims to characterize the oxylipin content of human milk EVs. Centrifugation and precipitation were used to isolate EVs from human milk (n = 20). The Folch method was used to extract lipids, and liquid chromatography-mass spectrometry (LC– MS) was used to qualify and …


The Role Of Elevation In The Migration, Physiology, And Genomic Diversification Of Birds, Jessie L. Williamson Aug 2024

The Role Of Elevation In The Migration, Physiology, And Genomic Diversification Of Birds, Jessie L. Williamson

Biology ETDs

Elevational gradients cause profound eco-climatic variation across short distances. Partial pressure of oxygen (PO2) is a severe challenge that organisms face at high elevations; due partly to specialization on PO2, most Neotropical bird species have narrow elevational ranges. However, a small fraction are elevational generalists that span sea level to high elevations, and a subset undertake extreme migratory journeys from low to high elevations biannually. My dissertation combines diverse approaches across levels of biological organization to understand how elevation impacts the ecology, evolution, physiology, and migration of montane birds. I examined ‘extreme’ elevational …


Avian Communities Monitored Along A Successional Chronosequence In Bottomland Hardwood Forests In The Lower Mississippi Alluvial Valley, Eamonn Alasdair Thurmond Aug 2024

Avian Communities Monitored Along A Successional Chronosequence In Bottomland Hardwood Forests In The Lower Mississippi Alluvial Valley, Eamonn Alasdair Thurmond

Electronic Theses and Dissertations

Bottomland hardwood forests in the Lower Mississippi Alluvial Valley have been extensively reduced due to agriculture conversion and altered hydrology. Remnant forests have undergone further degradation from sources such as a lack of forest management, invasive species, and reduced regeneration of oaks (Quercus spp.). Recent restoration efforts of bottomland hardwood forests have focused on implementing wildlife forestry practices that prioritize restoring wildlife habitat while retaining profitable timber harvests. In this study I surveyed bird communities in bottomland hardwood forests in the Lower Mississippi Alluvial Valley along a successional chronosequence. Birds were sampled using automated recording units over 10 days …


Application Of Criminology In Urban Ecology And Evolution: Routine Activity Theory And Field Equipment Disappearance Dynamics, Ignacy Stadnicki, Michela Corsini, Marta Szulkin Aug 2024

Application Of Criminology In Urban Ecology And Evolution: Routine Activity Theory And Field Equipment Disappearance Dynamics, Ignacy Stadnicki, Michela Corsini, Marta Szulkin

Biology Faculty Publications and Presentations

Research in urban ecology and evolution relies on the use of deployable scientific equipment. If left unattended in the field, scientific equipment may be prone to vandalism and theft, especially in the urban space. Here, we empirically applied a theory derived from the field of criminology, specifically the Routine Activity Theory (RAT) framework, to predict disappearance rates of scientific equipment in an ongoing urban ecology research project. First, we tested a routinely applied method of equipment protection – labelling – and investigated whether equipment disappearance varied with label information content and message tone. Second, we examined whether equipment attributes (price, …


Research Trends In Production, Separation, And Identification Of Bioactive Peptides From Fungi: A Critical Review, Tanvir Ahmed, Angéla Juhász, Utpal Bose, Netsanet Shiferaw Terefe, Michelle L. Colgrave Aug 2024

Research Trends In Production, Separation, And Identification Of Bioactive Peptides From Fungi: A Critical Review, Tanvir Ahmed, Angéla Juhász, Utpal Bose, Netsanet Shiferaw Terefe, Michelle L. Colgrave

Research outputs 2022 to 2026

Fungal-derived bioactive peptides (BPs) are increasingly attracting significant academic and industry research interest due to their high-quality protein content and potential environmentally friendly credentials. Fungi encompass a diverse range of species, some of which remain underexplored with demonstrated the ability to synthesise complex peptides with unique and potent bioactivities. While some recent reviews have focused on fungal protein sources and BPs, there remains a knowledge gap in the technologies and methods used to produce, isolate, and identify BPs from various fungal species. This article critically evaluates the strengths, challenges, and future directions of the recent methods and technologies employed in …


Venom Complexity Within Garter Snakes And The Role Of Diet In Toxin Diversification, Tucker Heptinstall Aug 2024

Venom Complexity Within Garter Snakes And The Role Of Diet In Toxin Diversification, Tucker Heptinstall

All Theses

Complex traits, such as body size and venom, are often under strong selection by

dietary ecology and can increase efficiency of prey capture and processing. To investigate relationships between ecology and trait evolution in Thamnophis, we amassed nearly 10,000 diet records for 32/35 Thamnophis species and classified each species’ dietary repertoire. We categorized 15/32 species as generalist predators and 17/32 species as specialist predators of varying prey groups and investigated the hypothesis that generalist predators have larger body size. However, we found no significant relationship between body size and dietary specialization. Venom has evolved over 100 times across the Tree …


Aging Antiviral Immunity In The Central Nervous System: Mechanisms And Implications, Artem D. Arutyunov Aug 2024

Aging Antiviral Immunity In The Central Nervous System: Mechanisms And Implications, Artem D. Arutyunov

Arts & Sciences Graduate Student Theses and Dissertations

The complex interplay between aging, neuroinflammation, and neuroimmune responses has become increasingly evident in recent years. Microglia, the resident immune cells of the central nervous system (CNS), play a pivotal role in maintaining neural homeostasis and responding to neuroinflammatory triggers. This dissertation focuses on the role that aging plays in microglial activation and neuroinflammation, specifically in the context of West Nile Virus (WNV) encephalitis. While the incidence of WNV is consistent across age groups, the risk of West Nile Neuroinvasive Disease (WNND), a serious complication of WNV infection, increases with advanced age. Using mouse models of WNV infection, our group …


Employing Single-Nucleus Rna-Seq To Uncover Genetic Factors Of Alzheimer Disease, Logan Brase Aug 2024

Employing Single-Nucleus Rna-Seq To Uncover Genetic Factors Of Alzheimer Disease, Logan Brase

Arts & Sciences Graduate Student Theses and Dissertations

Alzheimer’s disease (AD) stands as a daunting global health challenge, affecting millions of individuals worldwide. This burden will only intensify with an aging global population. Despite significant advances in understanding AD, further exploration is needed to enhance the development of treatments and therapeutics. Particularly, I am interested in identifying the molecular pathways involved and the cell types mediating the etiology of AD. This work underscores the ability of single nucleus RNA-seq to investigate these pathways at the cell-type level and mitigate many of the hurdles limiting the successful development of treatments for AD, including genetic heterogeneity and translation of discoveries …


Manipulation Of Cellular Proliferating Cell Nuclear Antigen (Pcna) During Herpes Simplex Virus Type 1 Infection, Jessica Packard, Jill A. Dembowski Aug 2024

Manipulation Of Cellular Proliferating Cell Nuclear Antigen (Pcna) During Herpes Simplex Virus Type 1 Infection, Jessica Packard, Jill A. Dembowski

Electronic Theses and Dissertations

Herpes simplex virus type 1 (HSV-1) is a double stranded DNA virus that replicates within the nucleus of host cells. Using accelerated native isolation of proteins on nascent DNA (aniPOND), cellular proteins were found to associate with HSV-1 replication forks. One host factor of interest is proliferating cell nuclear antigen (PCNA), the DNA sliding clamp that tethers DNA polymerases and DNA damage response proteins to replicating cellular DNA. Although HSV-1 encodes its own DNA polymerase processivity factor (UL42), PCNA plays a key role in HSV-1 infection. We used commercially available PCNA inhibitors and short hairpin RNAs (shRNA) to investigate how …


The Multi-Trophic Effects Of Buckthorn Removal, Amanda Jacobs Aug 2024

The Multi-Trophic Effects Of Buckthorn Removal, Amanda Jacobs

Great Lakes Center Masters Theses

European buckthorn (Rhamnus cathartica) is a non-native woody plant in North America that often grows in dense, monotypic stands, frequently displacing native plants and reducing species richness of invaded native communities. Given that plants are basal in most food webs, the homogenization of plant communities might be expected to cascade into homogenization at higher trophic levels (Hunter and Price, 1992). I investigated the multi-trophic effects of buckthorn removal at three levels: (1) ‘native,’ in which there were no buckthorn trees or shrubs, (2) ‘buckthorn trees,’ in which buckthorn was not removed and grew into spaced mature trees, and …


Unraveling The Behavioral Ecology Of The Western Diamond-Backed Rattlesnake (Crotalus Atrox) Through The Lenses Of Personality, Predator-Prey Interactions, And Crypsis, Oceane Da Cunha Aug 2024

Unraveling The Behavioral Ecology Of The Western Diamond-Backed Rattlesnake (Crotalus Atrox) Through The Lenses Of Personality, Predator-Prey Interactions, And Crypsis, Oceane Da Cunha

Open Access Theses & Dissertations

To thrive in an environment, individuals need to be able to forage efficiently and acquire mates. These resources are limited, and their acquisition depends upon the energy and time an individual chooses to allocate to each activity and the environmental conditions, leading to behavioral trade-offs. Different species, or even different individuals within the same population, respond to these trade-offs by employing contrasting strategies, leading to differential life-history outcomes. The overarching goal of this dissertation is to gain a better understanding of the trade-offs cryptic ambush mesopredators are facing using the western diamond-backed rattlesnake (Crotalus atrox) as a model species. Each …


Biochar Impacts On Soil And Sagebrush Seedling Establishment Across A Natural Recovery Gradient In The Sagebrush Steppe, Ashley Leavell Aug 2024

Biochar Impacts On Soil And Sagebrush Seedling Establishment Across A Natural Recovery Gradient In The Sagebrush Steppe, Ashley Leavell

Boise State University Theses and Dissertations

Large areas of the sagebrush steppe are destroyed by wildfire, which catalyzes invasive species growth, increases soil nitrogen availability, reduces soil water retention, and disrupts soil symbiont-plant interactions. These changes in biogeochemical properties may explain why restoration success remains limited. Biochar is a soil amendment created from pyrolyzed plant biomass that may reduce soil N availability and increase water retention. Our study aims to evaluate whether changing soil properties using biochar may enhance the survival of sagebrush seedlings. We installed an experiment south of Boise, Idaho at a site that burned in 1983. Nursery-grown sagebrush seedlings were hand-planted in November …


Uvc And Planetary Habitability: Insights From Desert Lichens And Cyanobacteria, Tejinder Singh Aug 2024

Uvc And Planetary Habitability: Insights From Desert Lichens And Cyanobacteria, Tejinder Singh

UNLV Theses, Dissertations, Professional Papers, and Capstones

An important question in astrobiology is whether life can exist under the levels of UVC radiation found on Archean Earth, Mars, and exoplanets. We investigated this question by studying the UVC survival of colonial cyanobacterium and lichens that grow in harsh desert environments and possess natural sunscreens. We irradiated them nonstop in a desiccated state with a UVC flux closely representing the upper limit on those planets: 55-60 W/m². After irradiation, we rehydrated and assessed their survival using chlorophyll fluorometry and by counting the number of viable colonies that formed on agar plates. All three study organisms survived two to …


Probing The Ecological Functions Of Thermophiles Using Cultivation-Dependent And Cultivation-Independent Techniques, Dengxun Lai Aug 2024

Probing The Ecological Functions Of Thermophiles Using Cultivation-Dependent And Cultivation-Independent Techniques, Dengxun Lai

UNLV Theses, Dissertations, Professional Papers, and Capstones

High-temperature geothermal springs are ecosystems that resemble early Earth, offering insights into the origins and early evolution of life. In these unique ecosystems, thermophilic microorganisms thrive. However, our knowledge of thermophiles remains limited. A major challenge is that many thermophiles remain uncultivated. The primary goal of this dissertation was to explore the diversity, metabolism, and ecological functions of thermophiles using cultivation-dependent and cultivation-independent approaches. Chapter 1 provides a broad overview of geothermal spring ecosystems and thermophiles, along with a roadmap of the dissertation. Chapter 2 documents a study on the response of specific thermophiles from Gongxiaoshe (GXS) Hot Spring in …


Challenges Of The Fentanyl Epidemic: Understanding The Crisis, Analyzing The Analogs, And Investigating The Detection Methods, Sophia Hontzas Aug 2024

Challenges Of The Fentanyl Epidemic: Understanding The Crisis, Analyzing The Analogs, And Investigating The Detection Methods, Sophia Hontzas

Graduate Student Dissertations, Theses, Capstones, and Portfolios

The fentanyl epidemic has become a significant public health concern, identified by a rise in overdose deaths pertaining to the use of illicitly manufactured fentanyl (IMF). In 2021 alone, there were 70,601 overdose deaths attributed to fentanyl, emphasizing the severity of the crisis. This paper discusses the challenges posed by fentanyl and its analogs, investigating the origins, market dynamics, biological impacts, and the issues with detection and regulation. While fentanyl was initially created as a potent pain reliever, its misuse has grown due to the presence of new analogs. Case studies provide insight into how fentanyl rose in popularity and …


Microbiome Assembly And Function In The Solitary Mason Bee, Osmia Lignaria (Megachilidae), Bailey Crowley Aug 2024

Microbiome Assembly And Function In The Solitary Mason Bee, Osmia Lignaria (Megachilidae), Bailey Crowley

All Graduate Theses and Dissertations, Fall 2023 to Present

Animal-microbe interactions can influence host biology, ecology, and evolution. The assembly and function of microbes found within animal hosts oftentimes depends on which species are involved. Advances in sequencing technologies have permitted the exploration of host-microbe interactions in a variety of animals, including bees. Early research aimed at understanding the microbiomes of social bees, such as honey bees and bumble bees, found that microbes prevent the spoilage of stored pollen, breakdown indigestible nutrients into smaller molecules available for uptake by the host, and also protect the host from pathogens. When environmental stressors, such as increased temperatures, disrupt the microbiome, the …


The Interactions Between Drought Tolerant Corn Hybrids And Plant Water-Stress On Weeds And Their Host Capability For Spider Mites, Mercy Adhiambo Odemba Aug 2024

The Interactions Between Drought Tolerant Corn Hybrids And Plant Water-Stress On Weeds And Their Host Capability For Spider Mites, Mercy Adhiambo Odemba

All Graduate Theses and Dissertations, Fall 2023 to Present

With climate change, it is predicted that more frequent high temperatures and drought severity will lead to an increase in damage caused by pests that thrive under these conditions. Spider mite outbreaks, for example, are associated with plant waterstress and there is evidence that some weeds are more resilient and adapted to drought than some crops, leading to major concerns for the management of these two pest types. Weeds directly compete with crops for limited resources, but what is unclear is which weeds harbor spider mites and whether they exacerbate the impact of spider mites on corn crops under water-stressed …


From Inbreeding To Admixture: How The Diverse Consequences Of Gene Flow Shape Evolutionary Dynamics And Population Viability, Amy L. Springer Aug 2024

From Inbreeding To Admixture: How The Diverse Consequences Of Gene Flow Shape Evolutionary Dynamics And Population Viability, Amy L. Springer

All Graduate Theses and Dissertations, Fall 2023 to Present

When Homo sapiens traveled out of Africa and interbred with the Neanderthals of Europe, human genes spread into the Neanderthal population. Likewise, genes from Neanderthals spread into the human genome—genes humans still carry to this day. The process whereby genetic material from one population is spread to another is known as gene flow. Gene flow—or the absence thereof—can have critical consequences for a population’s health and survival. On one hand, if no gene flow occurs, mating among close relatives can lead to high levels of inbreeding. Inbreeding can have devastating consequences for the health of populations, in some cases even …


Shifting Paradigms In Recreation Management: Applying Social-Ecological System Frameworks To Parks And Protected Areas, Noah Creany Aug 2024

Shifting Paradigms In Recreation Management: Applying Social-Ecological System Frameworks To Parks And Protected Areas, Noah Creany

All Graduate Theses and Dissertations, Fall 2023 to Present

Park and protected area (PPA) recreation management is often characterized by social, ecological, and managerial dimensions. These dimensions have increasingly been conceptualized as social-ecological systems (SESs) to understand the complex interrelationships between them. Contemporary trends of increased visitation on public lands in the United States, including US National Parks, have accentuated the complex interactions between the amount of recreation use, the capacity of the setting, the quality of the visitor experience, and ecological resource conditions. These challenges of managing recreation use and understanding these interactions will be further compounded by climate change and its effects on ecosystem composition and dynamics. …


Evidence For Partitioning? A Comparison Of Thermal Niche In Three Species Of Sympatric Lizards In Northeastern Utah, Kristopher B. Pedersen Aug 2024

Evidence For Partitioning? A Comparison Of Thermal Niche In Three Species Of Sympatric Lizards In Northeastern Utah, Kristopher B. Pedersen

All Graduate Theses and Dissertations, Fall 2023 to Present

Lizards actively maintain a narrow range of body temperatures through behavioral thermoregulation and microhabitat selection. Body temperature plays a critical role in many physiological processes. As a result, there is a range of body temperatures at which a lizard’s reproductive success (fitness) is maximized, known as the lizard’s thermal niche. There is strong evidence linking the available temperatures, or thermal properties of a microhabitat, to success in maintaining body temperatures within a preferred set range. Microhabitats have differing thermal properties, and so have different relative quality. Because thermal properties are limited in space and time, competition for high quality microhabitat …


Impacts Of Anthropogenic Disturbances And Urbanization On The Behavior And Morphology Of Two Free-Living Lizard Species (Uta Stansburiana And Aspidoscelis Neotesselatus), Layne O. Sermersheim Aug 2024

Impacts Of Anthropogenic Disturbances And Urbanization On The Behavior And Morphology Of Two Free-Living Lizard Species (Uta Stansburiana And Aspidoscelis Neotesselatus), Layne O. Sermersheim

All Graduate Theses and Dissertations, Fall 2023 to Present

Urbanization can alter wildlife, requiring species to adjust to anthropogenic changes via life history strategies. Reptiles are particularly vulnerable to these changes, as ectotherms directly rely on their environment to maintain their optimal homeostatic state. As urbanization changes the landscape, reptiles will have to adapt to anthropogenic change, but it is unclear what behaviors may be aiding in this adaptation and whether there are morphological tradeoffs existing to support this change. To analyze the impact of urbanization and anthropogenic disturbances on reptile behavior and morphology, I conducted three research studies on two different species – the common side-blotched lizard and …


Comparative Morphology And Development Of The Trigeminally Innervated Infrared-Imaging System In Boas And Pythons, Helen Bond Plylar Aug 2024

Comparative Morphology And Development Of The Trigeminally Innervated Infrared-Imaging System In Boas And Pythons, Helen Bond Plylar

All Graduate Theses and Dissertations, Fall 2023 to Present

Boas and pythons use specialized sense organs called pit organs to detect radiant heat. Pit organs in these lineages occur in paired arrays along the upper and lower jaws and are served by the trigeminal nerve (the fifth cranial nerve and one of the largest). Information from the pit organs travels via branches of the trigeminal to the brain and ultimately is processed in the optic tectum, along with information from the visual system. That means these snakes effectively “see” heat. While studies of the pitviper infrared-imaging system are numerous, very few studies of this system in pythons or boas …


Using Wasp Specimens In Taxonomic, Biogeographic, Evolution, And Informal Education Studies, Brenna Lynn Decker Aug 2024

Using Wasp Specimens In Taxonomic, Biogeographic, Evolution, And Informal Education Studies, Brenna Lynn Decker

All Graduate Theses and Dissertations, Fall 2023 to Present

Entomology collections hold an untapped wealth of information, from insect morphology, genetics, locality and association data, and potential for use in education. Especially with insects that generate initial fears, such as wasps, seeing insect specimens provides a safe environment to learn about their behaviors. Wasps are insects in the order Hymenoptera, along with ants and bees. The public may hold fears against wasps, due to their negative portrayal in various media, but they serve as integral components of a functional ecosystem. Even with their importance, many groups of wasps are still highly understudies. This dissertation aims to tackle this fear …


The Influence Of Oxidative Stress On Ion Homeostasis And Glycolysis Activation, With Implications For Neurological Health And Multiple Sclerosis, Xavier Hayes Aug 2024

The Influence Of Oxidative Stress On Ion Homeostasis And Glycolysis Activation, With Implications For Neurological Health And Multiple Sclerosis, Xavier Hayes

Graduate Student Dissertations, Theses, Capstones, and Portfolios

Multiple sclerosis (MS) is a neurodegenerative disease in which the body’s immune system attacks its own tissues, notably the neural cells, and one of the contributing factors to this is oxidative stress. Oxidative stress is the build-up of reactive oxygen species ROS that causes oxidative damage to the cells. Chronic and environmental stressors are explored as significant factors that exacerbate these conditions by disrupting cellular processes and energy metabolism. The paper reviews current literature on MS, examining the interplay between oxidative stress, environmental factors, and genetic predispositions. Additionally, it discusses how these factors contribute to MS, where the immune system …


Decision-Making In Rats: Effects Of Drug Abuse, Safa Binte Hossain Aug 2024

Decision-Making In Rats: Effects Of Drug Abuse, Safa Binte Hossain

Open Access Theses & Dissertations

Decision-making is a critical cognitive function, often impaired by substance abuse. Understanding the underlying mechanisms in both human and animal models is essential for developing effective treatments. This thesis aims to study approach-avoid decision-making in rats and focuses on the impacts of oxycodone self-administration and alcohol abuse on approach-avoid decision-making.We hypothesize that oxycodone self-administration will alter decision-making in female rats, revealing sex differences and distinct psychometric functions, alcohol habituation will similarly affect decision-making in male rats. The study involved 23 Long Evans rats (11 males and 12 females) for decision-making behavioral study connecting multiple levels of rewards and costs combinations. …


Signatures Of Selection, Gene Flow, And Genetic Drift On The Genomes Of A Recent Avian Radiation, Flor Brigitte Hernandez Camacho Aug 2024

Signatures Of Selection, Gene Flow, And Genetic Drift On The Genomes Of A Recent Avian Radiation, Flor Brigitte Hernandez Camacho

Open Access Theses & Dissertations

Speciation is not a discrete event but rather a gradual process that occurs along a continuum. Initially, populations remain genetically and reproductively connected, but they become reproductively isolated as the process of speciation progresses. Advances in DNA sequencing technology has helped our understanding of the processes that contribute to changes in the genetic composition of populations over the progression of speciation, also known as drivers of evolution (i.e. genetic drift, mutation, selection, and gene flow). Among them, hybridization, or the interbreeding between distinct lineages, is increasingly recognized as a natural process that can have significant consequences to the speciation process. …


An Analysis Of Fish Assemblages And Flow Regimes Upstream And Downstream Of Falcon Reservoir, Christopher J. Austin Aug 2024

An Analysis Of Fish Assemblages And Flow Regimes Upstream And Downstream Of Falcon Reservoir, Christopher J. Austin

Theses and Dissertations

The lower Rio Grande is regulated by Falcon and Amistad dams. Native fish species rely on the natural flow regime for habitat and spawning. I analyzed streamflow discharge and fish assemblages above and below Falcon Reservoir to assess potential impacts of dam impoundment. Fish collections were conducted by seine, and river discharge data was provided by the International Boundaries and Water Commission. I found significant differences in fish assemblages above vs below Falcon Reservoir, and the flow regime was significantly more altered downstream of Falcon Reservoir. I also identified two Species of Greatest Concern for Texas above Falcon Reservoir (Notropis …


Pfos Alters Metabolism In The Liver And Skeletal Muscle Of Cyp2b-Null And Humanized Cyp2b6-Transgenic Mice, Lanie Williams Aug 2024

Pfos Alters Metabolism In The Liver And Skeletal Muscle Of Cyp2b-Null And Humanized Cyp2b6-Transgenic Mice, Lanie Williams

All Theses

Perfluorooctanesulfonate (PFOS) is a persistent environmental pollutant previously used in industrial products such as fire-fighting foams, furniture, and stain-resistant coatings. PFOS is associated with adverse health outcomes, including hepatosteatosis and diabetes. Previously, humanized CYP2B6-transgenic (hCYP2B6-Tg) mice accumulated more PFOS than Cyp2b-null mice and experienced greater mortality; however, the Cyp2b-null mice experienced greater steatosis. Cyp2b-null and hCYP2B6-Tg mice were treated with 0, 1, or 10 mg/kg/day PFOS for 21 days. To determine how PFOS affected the metabolism of polyunsaturated fatty acids (PUFAs) oxylipin concentrations were measured via LC-MS/MS. Additionally, gene expression changes were measured using RNA sequencing. PFOS treatment increased the …