Integrative Biology Commons^™

Physiological Responses And Plant Trait Interactions With Coastal Dune And Swale Development, Emily C. Riffe

Theses and Dissertations

Vegetation is crucial to coastal ecosystems experiencing climate change and storm-induced disturbance. Plant species interact with the physical environment and are considered “ecosystem engineers.” Sand dunes and barrier islands are at the forefront of climate change impacts as they are barriers that protect landward habitat and communities. Nature based solutions are utilized to protect infrastructure on developed coastlines. Understanding how dominant plant species interact with and alter the physical environment enhances our understanding of the mechanisms of change and consequences to the system. The goal of this research was to quantify physiological and functional trait differences in dominant species found …

Anoxia And Re-Oxygenation At Colder Temperatures In Goldfish (Carassius Auratus): Effects On Oxidative Stress And Metabolites, Matthew E. Trzcinski

Theses and Dissertations (Comprehensive)

Under the ice of ponds and lakes, goldfish (Carassius auratus) can survive weeks of anoxia at low temperatures by conserving ATP and by reducing their metabolic rate and relying on liver glycogen stores to meet their ATP demands using glycolysis. The following period of re-oxygenation is also known to be damaging in most vertebrates because it can lead to the generation of reactive oxygen species (ROS) that can cause oxidative damage to lipids, proteins and nucleic acids. Anoxia tolerant vertebrates such as the goldfish and crucian carp (Carassius carassius) accumulate reduced molecules with anoxia, overwhelming the …

Influence Of Temperature On Tfm Tolerance In Lake Sturgeon, Emily Bouffard

Theses and Dissertations (Comprehensive)

The lampricide, 3-trifluoromethyl-4-nitrophenol (TFM), has been used to successfully control invasive sea lamprey (Petromyzon marinus) in the Laurentian Great Lakes for over 50 years. TFM’s effectiveness is due to the relatively low capacity of sea lamprey to detoxify TFM. Water temperature has been shown to increase TFM tolerance in larval sea lamprey. However, the effects of temperature on TFM sensitivity in non-target species such as the endangered lake sturgeon (Acipenser fulvescens) are poorly understood, particularly during their early life stages. To determine how temperature affected TFM sensitivity, age 1-year-plus (1+) lake sturgeon acclimated to 8, 16, …

Timing Of Migration And Seasonal Movements Of Arctic Grayling (Thymallus Arcticus) In Relation To Water Temperature In The Kakisa River And Upper Mackenzie River, Nwt: Results From An Acoustic Telemetry Study., Levi Snook

Theses and Dissertations (Comprehensive)

Arctic grayling (Thymallus arcticus) are a cold-water salmonid that inhabit waterbodies throughout the circumpolar regions of the northern hemisphere. In the last decade, Ka'a'gee Tu First Nation members as well as local sport fishers, have observed lower catches of Arctic grayling during their annual spawning run in the Kakisa River, NWT. Many potential causes of this decline have been hypothesized including climate change and over harvesting. Outside of the general annual spawning activity in the headwaters of the Kakisa River, the ecology of the population, including post-spawn habitat use and migratory patterns, remained understudied. To address these knowledge gaps, acoustic …

Reversible Degradation Of Peptidoglycan By Lytic Transglycosylases, Aaron Devereaux

Theses and Dissertations (Comprehensive)

Antimicrobial resistance continues to be a burden on the global healthcare system with an estimated cost of billions of dollars and millions of deaths each year. Recently, there has been little to no development on new antibiotics to treat bacterial infection, and any that are developed become resisted to within a few years. Both Gram-positive and Gram-negative bacteria contain a mesh-like layer called peptidoglycan (PG) that surrounds their cells providing strength, cell shape, and protection from their environments. This layer is a polymer of N-acetylmuramic acid (MurNAc) and N-acetylglucosamine (GlcNAc) connected via a b-1,4-glycosidic bond, with each strand being cross-linked …

Quantifying Ecological Processes Predicting Barren-Ground Caribou (Ɂetthën; Rangifer Tarandus Groenlandicus) Occurrence Across A Heterogenous Northern Indigenous Protected And Conserved Area., Eric Jolin

Theses and Dissertations (Comprehensive)

Northern ecosystems are experiencing a period of rapid and unprecedented change, with implications for species distributions, mammal community dynamics, and habitat associations. Understanding the ecological processes that shape species distributions is crucial for developing effective conservation strategies that can adapt to such change. This study examines drivers of barren-ground caribou occurrence, a species of cultural and ecological significance, across Thaıdene Nëné Indigenous Protected Area, an ecologically intact landscape of high habitat heterogeneity straddling the treeline of the Northwest Territories. I use spatial and temporal variation in caribou detections generated by camera traps to test the relative importance of apparent competition, …

Lichen It: Optimizing Post-Fire Caribou Lichen Transplantation And Assessment, Elise Brown-Dussault

Theses and Dissertations (Comprehensive)

Caribou lichen species are common in mid- to late-seral boreal forests, serving as an important winter diet staple for boreal woodland caribou. However, as climate change causes boreal wildfires to increase in size, severity, and frequency, available tracts of mature forest are decreasing, diminishing the extent of mature caribou lichen stands. Caribou lichens reproduce vegetatively, so bigger and more severe fires could exacerbate their dispersal limitations, potentially extending the timeline for caribou lichen stand recovery beyond 80 years. Trials have shown that “transplanting” caribou lichen fragments into disturbed areas can lead to the establishment of caribou lichen mats; as such, …

Characterizing The Targeting Of Toc159 Receptors To The Chloroplast Outer Envelope Membrane And Their Role In The Assembly Of Distinct Toc Complexes, Michael Fish

Theses and Dissertations (Comprehensive)

Global agriculture and food security face challenges from climate change, population growth, and other human-driven pressures. Enhancing our understanding of plant biology, particularly chloroplast function, is critical for improving crop yield and stress resilience. As the sites of photosynthesis and key regulators of plant responses to environmental cues, chloroplasts depend on the precise import of thousands of nuclear-encoded proteins to maintain their biogenesis and function. While much is known about the core translocon components in the chloroplast outer envelope membrane that form the TOC complex, the mechanisms underlying their targeting, assembly, and regulation remain incompletely understood.

Plastids, including chloroplasts, evolved …

Npr1 As A Temperature-Sensitive Regulator Of Pipecolic Acid-Mediated Plant Systemic Immunity, Spencer Tout

Theses and Dissertations (Comprehensive)

Healthy plant development requires balancing both abiotic (e.g. climate) and biotic (e.g. pathogen) challenges, which intercept important signaling pathways in plants. For example, climate change-associated elevated temperature can negatively modulate various aspects of plant immunity, including the production of central immune signals salicylic acid (SA) and N-hydroxypipecolic acid (NHP). Since SA and NHP signaling both require the master immune co-activator protein NON-EXPRESSOR OF PATHOGENESIS-RELATED GENES 1 (NPR1), it is important to investigate NPR1 as a potentially temperature-regulated molecular hub. Although the NPR1 gene is not transcriptionally downregulated at elevated temperatures (28° C vs. 23° C), little is known about …

Macroinvertebrate Communities And Food Web Structure In Tundra Streams Are Shaped By Substrate Size And Beaver Impoundments, Mathew K. Mervyn

Theses and Dissertations (Comprehensive)

North American beavers (Castor Canadensis) are expanding their range into the Arctic tundra as climate change drives earlier ice and snowmelt, and increased shrub cover. As ecosystem engineers, beavers build dams that alter water chemistry by creating impoundments within streams, trapping sediment and organic matter, and modifying nutrient cycling. This thesis evaluates how beaver impoundments interact with natural geomorphic variation in tundra streams and how impoundments affect tundra freshwater ecosystems in the western Canadian Arctic.

In Chapter 2, I compared water chemistry and benthic macroinvertebrate (BMI) community composition across 16 stream reaches, including those with and without beaver dams, with …

Tricolored Bat (Perimyotis Subflavus) Population Genetic Structure In The Southeastern United States, Laura Henderson

Master's Theses

Tricolored bats (Perimyotis subflavus) have experienced substantial population losses from white-nose syndrome (WNS), a disease caused by the pathogenic fungus Pseudogymnoascus destructans (Pd) which infects hibernating bats. Determining population genetic structure helps assess genetic diversity and the impacts of wildlife threats to populations. Pre-WNS data shows weak-to-negligible structure and panmictic P. subflavus populations at core portions of their range. However, current genetic data from their southeastern U.S. range is lacking. I sought to determine whether recent genetic data help resolve genetic structure among southeastern populations and assess genetic differences at two stages of impact: post-WNS and …

Exploring The Salinity Tolerance Of Zooplankton Communities On The Great Plains, Abbeneet Binning Bath, Derek Gray

Theses and Dissertations (Comprehensive)

Palaeoecological data shows fluctuating salinity levels in lakes across the Great Plains due to alternating wet and dry periods over the last two millennia. Droughts caused by this natural variation may be exacerbated by anthropogenic climate change, as the Great Plains are expected to become drier over the coming decades. As conditions become drier, the evaporation of water will increase the salinity of lakes across the region. Increases in salinity may significantly impact biodiversity, including important members of lake food webs such as zooplankton. Due to the region's history of alternating wet and dry periods, zooplankton may have adapted to …

Feeling Blue: The Effects Of Blue Light Exposure On Reproduction And Physiology In Drosophila Melanogaster, Laura Hampel

Theses and Dissertations (Comprehensive)

Blue light, the wavelengths ranging from ~400-500 nm, is emitted from the sun and more recently, by artificial lights including those in technology. In humans, prolonged exposure to blue light has been consistently linked to circadian rhythm disruption and retinal damage, and has also been associated with changes in neurodegeneration, aging, mortality, and oxidative stress in model organisms. This thesis explores the multifaceted effects of blue light exposure through two independent but complementary approaches. An initial rapid review of the current state of knowledge on blue light induced oxidative stress in humans was conducted. This revealed that the most studied …

Molecular Insights Into The Impact Of Bone Marrow Stroma, Cb-6644 Inhibition Of The Ruvbl1/2 Complex, And Cebpβ On Regulating Drug Sensitivity In Multiple Myeloma, Sebastian Adam Dziadowicz

Graduate Theses, Dissertations, and Problem Reports (ETD)

Multiple myeloma (MM), is a hematological cancer originating in plasma cells. Currently multiple myeloma represents a significant clinical challenge due its incurable nature mainly due to inevitable drug resistance. MM is characterized by abnormal plasma cell proliferation within the bone marrow and production of abnormal immunoglobulin resulting in a plethora of physiological abnormalities. Although a rare malignancy, MM accounts for 1% of all cancers and currently has five-year survival rate of around 50%. Utilizing a combination of laboratory experiments and bioinformatics techniques, this dissertation examines multiple layers of MM physiology in the context of regulating drug resistance or sensitivity. First, …

Florida Scrub Is Nuts (And Drupes): Fruit Production And Consumption In Florida’S Fire-Prone, Xeric Uplands, Warren G. Abrahamson Ii

Faculty Journal Articles

This is a story about how plant size, fire, and climate affect fruit and nut production (i.e., mast) in Florida’s fire-prone, xeric uplands and the importance of mast as food for wildlife. To set the stage, let’s first explore the primary mast-producing plants of Florida’s xeric uplands: oaks, hickory, and palmettos.

Elongate Locomotors Show Consistent Torque Patterns Across Substrates, Spencer Bradford, Henry Astley

Williams Honors College, Honors Research Projects

The four main movements found in snakes are understood mainly due to external study; however, muscular forces and resulting torques are poorly known. The main research objective is to study the torque production on different substrates using a snakebot. The study will give a rudimentary model for torque production on different substrates. It can then be compared against biological systems to understand snake movement at a muscular level. This study used a snakebot, allowing direct assessment of the current being run through each of its motors (proportional to torque). Data was then examined using a Principal Component Analysis test for …

Assessing Genetic Diversity And Population Structure In The Imperiled Aconitum Reclinatum (White Monkshood), An Endemic Wildflower Of Central Appalachia, Diamanda A. Zizis

Master’s Theses

Aconitum reclinatum, white monkshood (Ranunculaceae), is a Pennsylvania critically imperiled plant species found in five states of the Appalachian region of the United States: Pennsylvania, West Virginia, Virginia, North Carolina, and Tennessee. This plant is adapted to cool, moist environments but faces threats from increasing habitat loss, deer browse, logging, and changes in rainfall and temperature associated with climate change. Comprehensive knowledge of A. reclinatum genetic population structure remains limited. To address this, we collaborated with Natural Heritage programs within the range of A. reclinatum to sample populations across the species distribution and generate a genotyping-by-sequencing data set of …

The Prize Biter Of Modernity? Investigating Killer Whale Bite Mechanics, Daniel Hong

West Chester University Graduate Theses, Dissertations, and Final Projects

Although the killer whale (Orcinus orca) is a cosmopolitan apex predator, very little work has been done on its feeding biomechanics. Here I use finite element analysis to investigate the mandibular stiffness of a juvenile male Bigg’s killer whale, and compare it to that of the false killer whale (Pseudorca crassidens) and the saltwater crocodile (Crocodylus porosus). Full mandibles and left and right halves of mandibles are simulated under FEA. I also estimate the total jaw muscle force produced by the Bigg’s killer whale using the dry skull method. The killer whale lacks an …

Molecular Characterization Of Fungus-Arthropod Associations, Angie M. Martin

Graduate Theses, Dissertations, and Problem Reports (ETD)

Arthropods, or phylum Arthropoda, are the largest group of animals, accounting for over three quarters of all animal records on NCBI Taxonomy. And yet, only 40% of all deposited sequences on NCBI Nucleotide come from arthropods. Clearly, arthropods are an understudied group of animals: they are small, often drab, and lead lives very alien to our own. Arthropods have chitinous exoskeletons, segmented bodies, and jointed appendages, and include crabs, barnacles, insects, spiders, and millipedes. Since the era of DNA based studies took off in the 1980s, DNA and other small molecules have been integral to our understanding of the Earth …

The Impacts Of Permafrost Thaw Slumps On Arctic Stream Ecology, Maria Dolan

Theses and Dissertations (Comprehensive)

Climate change is intensifying permafrost thaw across terrain of the circumpolar Arctic. Increased temperatures and rainfall at northern latitudes have resulted in the expansion of thermokarst features such as retrogressive thaw slumps, which make previously frozen debris available for transport into nearby river systems. In the Peel Plateau, Northwest Territories, the mobilization of these materials exposes rivers to a large quantity of sediment and solutes that may act as a chronic, press disturbance, potentially altering stream food webs. Here, I examine if: 1) thaw slumps have driven changes to the physical and biological properties of slump impacted streams since an …