Life Sciences Commons^™

Educating Dietetics Students About The Nutritional Concerns Of Older Adults, Lily Brickman

Electronic Theses and Dissertations

The percentage of individuals in the United States who fall within the 65 years and older cohort is anticipated to increase substantially over the next decade due to the large baby boomer generation aging into this category by 2030. Consequently, the healthcare demands of older adults are expected to increase, and medical and healthcare providers must be educated and prepared to meet the unique needs of this population. The purpose of this study is to help learn why interest in FSN 406 Nutritional Care of Older Adults has been so low since its inception in 2020, and whether other institutions …

Barriers To And Opportunities For Adoption In Maine’S Aquaculture Industry, Caitlin Cleaver

Electronic Theses and Dissertations

Aquaculture, or the farming of marine species, can diversify coastal economies, but development of this industry is hindered by negative perceptions or regulatory constraints. Commercial fishers are logical adopters of aquaculture, but can also mount opposition to its growth. This dissertation utilized innovation theory to understand fishers’ perceptions of and willingness to adopt aquaculture and drivers of and barriers to scallop aquaculture development in Maine (USA). Through a mail survey, lobster fishers’ perceptions of Maine’s aquaculture industry and their willingness to adopt aquaculture were assessed (Chapter 2). Individuals who were more satisfied with government management of aquaculture held more positive …

Strategies To Promote Value And Resilience In The American Lobster (Homarus Americanus) Industry, Nicole Orminski

Electronic Theses and Dissertations

The American lobster (Homarus americanus) fishery is the most valuable single-species fishery in the United States and Canada (DFO, 2021; NOAA Fisheries, n.d.). Coastal communities on both sides of the border rely on the American lobster supply chain, which economically links the two countries with one another and with other countries around the globe. Ongoing disruptions (or shocks) threaten the functionality of the supply chain, and increased globalization leads to greater exposure to shocks as they are transmitted between systems. One research study described in this thesis aims to add value to the industry via post-harvest treatment of …

Quantum Computations And Molecular Dynamics Simulations: From The Fundamentals Of Antimicrobial Resistance To Neurological Diseases, Angel Tamez

Electronic Theses and Dissertations

Biophysical phenomena are modeled using a combination of quantum and classical methods to interpret and supplement three distinct and diverse problems in this dissertation. In the first project, decarboxylation reactions are ubiquitous across chemical and biological disciplines, yet the origin of non-catalytic solvent effects remains elusive. Specific solvent structure and energetics have not been well described for the monoanion of malonate, nor corrected from the gas-phase charge-assisted intramolecular hydrogen bond model known as “pseudochair”. In the aqueous phase, a low-lying energy conformer known as the “orthogonal conformation” is computed to be preferred by a three-water cluster of hydrogen bonding over …

Form And Risk Class Distribution And Its Effect On Estimated Product Ratios In Commercial Species Commonly Found In Northeastern Forests And A Comparative Analysis Of Contrasting Field Inventory Methodologies, Ryan Smith

Electronic Theses and Dissertations

Estimating product ratios in hardwood forests is difficult due to the highly complex stem forms and diverse growth and regeneration strategies found in hardwood species. This is of particular concern for landowners with large ownerships requiring robust product potential estimates as part of both short-term tactical harvest planning and long-term growth and yield projections. Hardwood-dominated forests are generally managed for high-value sawlog and veneer products. This makes it increasingly important to identify strategies for improving hardwood management to meet economic (maximizing sawlog recovery) and ecological (maintaining healthy and diverse forests) goals.

This study seeks to achieve two primary goals. The …

Improving Use Of Soil Health Practices In Kansas: A Study Of Barriers To Adoption And Novel Incentive Programs, Sara Kelemen

Electronic Theses and Dissertations

As climate change continues to affect agroecosystems, farm resilience will become increasingly important. To feed a growing global population, the future of agriculture must be secure and ultimately, sustainable. Use of soil health practices can increase farm resilience through improved provision of ecosystem services. Not only does this benefit the farm agroecosystem, it can also improve also agronomic outcomes while also improving landscape scale ecological conditions. It can also can have positive impacts on profitability. The benefits to use of soil health practices are well documented, yet rates of adoption in the United States remain relatively low. Therefore, research must …

Understanding The Impacts Of Anthropogenic Effects An Habitat Variability Interactions On Maine's Rocky Intertidal Ecosystem, Laura Braun

Electronic Theses and Dissertations

The rocky intertidal ecosystem is an important ecological and cultural aspect of the picturesque Maine coast, playing a vital role in not only Maine’s coastal ecosystem, but also to Maine’s economy. It’s distinct community structure along the sharp elevational gradient and the presence of daily stressors (wave action, heat, and desiccation), make the rocky intertidal ecosystem an important model ecosystem to monitor for effects from anthropogenic impacts. In this thesis, I describe attempts to monitor and understand the impacts of two of these anthropogenic impacts on this system: climate change and industrial harvesting of Ascophyllum nodosum along Maine’s coast. For …

Quantitative Silviculture Of Northern Conifers, David G. Ray

Electronic Theses and Dissertations

Quantitative tools used to guide the management of important northern conifer species require updating and refinement to address changes in the contemporary resource and evolving objectives of ownership. This work builds on an extensive body of knowledge about stand density management and innovates some new approaches. In sum, the three chapters presented herein: 1) seek to strengthen and more fully articulate arguments for adopting relative density as a primary metric of stand density assessment, 2) quantify minimum stand densities to achieve full site occupancy and argue for more parity with treatment of maximum stand density, and 3) present an empirically …

Genetic Characterization Of Centromere-Mediated Uniparental Genome Elimination In Arabidopsis, Diana Spencer

Electronic Theses and Dissertations

The production of haploids through crossing was first discovered from instances of interspecies crosses in Nicotiana spp. in 1924. Since then, haploid induction crosses has been used to improve plant breeding programs and commercially utilized in a number of crop industries. The generation of doubled haploid instantaneously creates a pure homozygous line, therefore eliminating the need for several generations of inbreeding. There are several pathways to induce haploids in plants: of these methods, centromere-mediated genome elimination pathway engenders the highest haploid induction rate (HIR) with up to 45% in Arabidopsis compared to 15% through phospholipase-mediated haploid induction in maize. Centromere-mediated …

Carbon Dioxide Emissions From Deadwood In Forests Of The Northeastern United States, Zoe Read

Electronic Theses and Dissertations

As the climate changes, understanding the sources and sinks of greenhouse gases such as carbon dioxide (CO₂) is increasingly important. However, several components of the carbon cycle within forests remain poorly understood. For example, knowledge gaps exist in our understanding of CO₂ emissions from coarse woody material (CWM; logs and stumps), including how emissions change over time, how they are influenced by environmental variables, and how they compare to soil and ecosystem-level CO₂ emissions.

To fill these knowledge gaps, we examined CO₂ emissions from CWM at three sites. We sampled 18 red spruce (Picea …

A Sky Island Perspective: New England Alpine Plant Distributions Across The Region, Andrea Tirrell

Electronic Theses and Dissertations

Alpine ecosystems around the globe are at risk due to climate change, human disturbance, and habitat loss. New England alpine zones are small and fragmented, which could make them vulnerable to global change. However, the persistence of tundra relics throughout the Holocene suggests the persistence of these communities in microclimate refugia. Assessing the near-term vulnerability of alpine plant communities is challenged by a lack of standardized, repeat surveys and long-term monitoring data, which presents a challenge for the many agencies monitoring New England’s alpine zones. Island biogeography theory predicts that alpine species richness is a function of area, but this …

Using Reflex Actions To Predict Delayed Post-Harvest Mortality Of American Lobster (Homarus Americanus) In Maine’S Lobster Supply Chain, Cassandra Leeman

Electronic Theses and Dissertations

In live seafood industries, maintaining product quality and survivorship are critical aspects of the supply chain infrastructure. Post-harvest mortality in the American lobster (Homarus americanus) fishery can result in a significant loss in revenue for the largest single species fishery in North America. In Maine, the wholesale lobster distribution supply chain directly and indirectly supports state and local economies, providing almost $1 billion in revenue and dominates the fishery, producing 82% of the total lobster landings in the USA (Donihue, 2018; NOAA, 2021). However, at least 2% of the lobster landed in Maine die before they reach consumers, representing an …

Microplastic Accumulation In The Digestive Tract Of Young-Of-Year Atlantic Sharpnose Sharks (Rhizoprionodon Terraenovae) In The Grand Strand, Sc, Andrew Curtis Sitlinger

Electronic Theses and Dissertations

This study focused on the presence and accumulation of microplastic fibers in the digestive tract and livers of young-of-year Atlantic Sharpnose Sharks (Rhizopriondon terraenovae) from two sampling locations along the Grand Strand of South Carolina. R. terraenovae is a small, mesopredatory elasmobranch found abundantly along northwestern Atlantic Ocean coastlines. Thirty specimens of R. terraenovae were collected from May through August of 2020. Microplastics were found in all specimens. A total of 672 plastic particles were identified over the course of the study, with an average of 22.4 ± 10.5 (SD) plastics per specimen. The majority of the plastics were classified …

Fine-Scale Site Selection Of Strand-Feeding Common Bottlenose Dolphins (Tursiops Truncatus) And Their Prey, Deborah Kleinclaus

Electronic Theses and Dissertations

Strand-feeding is a unique, cooperative foraging strategy used by some common bottlenose dolphins (Tursiops truncatus) at low tide in South Carolina and Georgia salt marshes, where a group of dolphins charges schools of fish, thrusting them onto the bank with their bow wave and then capturing prey items onshore. Strand-feeding dolphins are estuarine residents and frequent predictable stranding sites, suggesting an intimate knowledge of the area. Dolphin behavior prior to stranding suggests they do not herd the fish before charging, but instead prey on fish already shoaling near the bank. The use of active acoustics from strand-feeders in order to …

Extraction, Analysis, And Comparison Of Microplastics In Sc Marsh Substrates, Austin G. Sige

Electronic Theses and Dissertations

The global, rapid increase in plastic production is a widespread problem for coastal environments such as marshes that present favorable conditions for plastic retention. This study looked at the microplastic abundance within three previously unstudied South Carolina marshes located in Myrtle Beach, Murrells Inlet, and Waties Island. A comparison between the microplastic types and abundances between locations provided knowledge about the impacts of sediment composition (sand, silt, clay, and organic matter) on microplastic sequestration. This study also produced a novel microplastic extraction methodology for cohesive marsh sediment that used elutriation to effectively break apart aggregates prior to chemical digestion and …

Abundance And Growth Of Juvenile Atlantic Sturgeon In The Edisto River, Sc, Molly Katherine Takacs

Electronic Theses and Dissertations

Information on abundance and body growth are important for understanding the status and health of populations, and this information can be used to guide and monitor conservation and recovery efforts for species of conservation concern. The Atlantic Sturgeon (Acipenser oxyrinchus oxyrinchus) is an anadromous fish native to the Atlantic coast of the United States and Canada. Due to overfishing and habitat degradation, population levels declined, and Atlantic Sturgeon were placed on the Endangered Species list in 2012. Although there is substantial research on adult Atlantic Sturgeon, knowledge about their early life history is lacking. The objective of this study were …

Next-Generation Sequencing Shows Increasing Temperatures Affect Stream Fungal Communities, Regan Hodgson

Electronic Theses and Dissertations

Under climate change predictions, surface air temperature is expected to continue to rise and will likely affect functioning of stream ecosystems and microbial communities. Aquatic hyphomycetes are key fungal decomposers of plant litter in headwater streams controlling carbon, energy, and nutrient flows to higher trophic levels. This project addressed the effects of temperature on stream fungal communities in two recently conducted experiments (microcosm and streamside channel studies) using Illumina sequencing. The objectives were to determine (1) if temperature affects community structure of stream fungi based on relative abundances of ITS2 rDNA sequences, (2) if the effects of temperature on aquatic …

Distribution And Soil Characteristics Associated With The Neches River Rose-Mallow (Hibiscus Dasycalyx), Morgan E. Langlinais

Electronic Theses and Dissertations

The Neches River rose-mallow, Hibiscus dasycalyx, is a rare herbaceous perennial endemic to East Texas. The threatened, obligate wetland species is currently at risk of being lost in the wild due to habitat loss, encroachment of nonnative and native plant species, and hybridization with two other Hibiscus congeners, Hibiscus laevis and Hibiscus moscheutos. Known locations of each of the three Hibiscus species were used to measure select soil characteristics and habitat variables associated with each of the rose-mallows. H. dasycalyx was concluded to be associated with more fertile soils and slightly more canopy coverage than H. laevis and …

Sequencing And Functional Characterization Of A Latrodectus Geometricus Defensin, Lg-Defensin, Jacklyn Victoria Thompson

Electronic Theses and Dissertations

Defensins are small, cysteine-rich, immune related proteins described to be the most widespread family of invertebrate antimicrobial peptides. Presently, there is limited information regarding spider defensins. In this study, a new defensin peptide was described in Latrodectus geometricus, Lg-defensin. The full open reading frame was resolved using RACE and de novo assembly, followed by a bioinformatical analysis and phylogenetic alignment to determine conserved sequence patterns and structural similarities to other defensins. Next, the functionality of Lg-defensin was determined using in vitro RNA interference to assess what impact silencing had on the spider’s ability to control a gram-positive and gram-negative bacterial …

Return-To-The-Platform: The Case Of A Collegiate Level Weightlifter Recovering From A Meniscus Injury, Nicholas Harden

Electronic Theses and Dissertations

The purpose of this study was to observe physiological metrics relative to training-induced adaptations in conjunction with laboratory- and competition-based performances in a super-heavyweight weightlifter recovering from a meniscus injury. A retrospective analysis was conducted on a collegiate level male weightlifter (23.2 yrs; 131.9 kg; 187.3 cm) over the course of 21-weeks post-meniscus surgery. Body mass, body fat percentage, hydration status, vastus lateralis muscle cross-sectional area, jump performance, and isometric midthigh pull were regularly assessed as part of an ongoing athlete monitoring program. Pre-injury baseline (T0) measurements were collected relative to a major national competition (COMP1). Post-injury measurements took place …

Investigating The Pi3k/Akt/Atm Pathway, Telomeric Dna Damage, T Cell Death, And Crispr/Cas9-Mediated Gene Editing During Acute And Chronic Hiv Infection, Sushant Khanal

Electronic Theses and Dissertations

Human Immunodeficiency Virus (HIV) infection initiates major metabolic and cell- survival complications. Anti-retroviral therapy (ART) is the current approach to suppress active HIV replication to a level of undetected viral load, but it is not a curative approach. Newer and sophisticated gene editing technologies could indeed be a potent antiviral therapy to achieve a clinical sterilization/cure of HIV infection. Chronic HIV patients, even under a successful ART regimen, exhibit a low-grade inflammation, immune senescence, premature aging, telomeric DNA attrition, T cell apoptosis, and cellular homeostasis. In this dissertation, we investigated CD4 T cell homeostasis, degree of T cell apoptosis, an …

Light And Temperature Entrainment Of Two Circadian-Driven Behaviors In The Flesh Fly Sarcophaga Crassipalpis, Raven Ragsdale

Electronic Theses and Dissertations

Circadian rhythms dictate the timing of both once-in-a-lifetime adult emergence (eclosion) and daily locomotor activity rhythms in the flesh fly S. crassipalpis. Light cycles are considered the primary environmental time cue (zeitgeber), but the life history of S. crassipalpis suggests that temperature cycles (thermocycles) may also play a key role. This work evaluates the efficacy of thermocycling as a zeitgeber in S. crassipalpis. We found that shifting both light and temperature cycles of sufficient amplitude affect the phasing of eclosion and locomotor activity, but result in different patterns. Additional experiments suggest greater thermocycle sensitivity during the late metamorphic …

Investigation Of Human N-Acetyltransferases (Nat1 And Nat2) Genetic Polymorphisms In Susceptibility To Aromatic Amine And Alkylaniline Genotoxicity., Mariam Habil

Electronic Theses and Dissertations

Arylamine N-acetyltransferases, NAT1 and NAT2, catalyze the detoxification and/or activation of carcinogens. Single nucleotide polymorphisms or SNPs result in different human NAT1 and NAT2 genotypes. We hypothesize that different NATs alleles will impact levels of N-acetylation, HPRT mutations, DNA damage and oxidative stress induced by carcinogens. NER-deficient Chinese hamster ovary (CHO) cells transfected with human CYP1A2 and NAT1*4, NAT1*14B, NAT2*4, NAT2*5B or NAT2*7B have been used to investigate N-acetylation of benzidine, β-naphthylamine (BNA), and 4, 4’-methylene bis (2-chloroaniline) (MOCA) as aromatic amines and 3,4-dimethylaniline (3,4-DMA) as one of alkylanilines and their associated toxicity. Our …

Effects Of Prescribed Fire Regimes On White-Tailed Deer (Odocoileus Virginianus) Browse, Forage, And Nutrient Availability In The Pineywoods Ecoregion Of Texas, Wyatt L. Bagwell

Electronic Theses and Dissertations

Fire is a management tool for white-tailed deer (Odocoileus virginianus) habitat, influencing browse availability, herbaceous production, and nutrient content. In 2020 and 2021, this study utilized 46 plots across East Texas to assess these habitat components. A stem count index survey method was used to assess browse utilization prior to April in both years, and preferred browse species were clipped and analyzed for nutrient availability, and herbaceous production was also measured. Additionally, white-tailed deer population data, browse survey data, and recent fire history were obtained from five different wildlife management areas to examine their relationship. Deer had preferences …

Seabirds As Proxies For Past El Niño Events In Coastal Peru: An Archaeo-Ornithological Approach, Heather A. Landazuri

Electronic Theses and Dissertations

This thesis sets an initial foundation for an archaeo-ornithological approach to understanding past El Niño events on the coast of Peru and the use of avifaunal remains as proxies for ecological conditions. Although faunal remains from archaeological sites do not provide exact representations of past environmental conditions, and bird remains can be especially challenging environmental indicators, their presence does reflect decisions made by human occupants in response to environment. Additionally, zooarchaeological data offer a reflection of past animal availability and use, much of which is at least in part determined by environmental conditions. Here I examine the extent to which …

A Functional Study Of Topological Dna Problem In Human T Cells During Chronic Viral Infection, Xindi Dang

Electronic Theses and Dissertations

T cells play an important role in adaptive immune system against viral infections, while premature aging and dysfunction of T cells induced by unrepaired DNA damages are always non-negligible snags during the long-term of fighting with chronic viral infections, such as Hepatitis B virus (HBV), Hepatitis C virus (HCV) or Human Immunodeficiency Virus (HIV) infection. In this dissertation, we investigated the role of topological DNA damage in reprogramming telomeric DNA damage responses (DDR), mitochondrial metabolisms, and T cell functions using CD4+ T cells derived from individuals with chronic viral infections or healthy subjects treated with topoisomerase inhibitors. The healthy human …

Importance Of The Microhabitat And Microclimate Conditions In The Northern Gray-Cheeked Salamander (Plethodon Montanus) Across An Elevation Gradient, Trevor Chapman

Electronic Theses and Dissertations

The southern Appalachian Mountains have among the highest salamander diversity in the world, largely due to local speciation in the family Plethodontidae. Plethodontid salamanders (i.e., lungless salamanders) are particularly sensitive to habitat climate conditions due to their reliance on cutaneous respiration, and their immediate environmental conditions (microhabitat) likely influence their dispersion and activity more than the large-scale atmospheric conditions. The Northern Gray-cheeked salamander (Plethodon montanus) is restricted to high elevations in the Appalachian Mountains. Our goal was to investigate the relationship between P. montanus and its microhabitat by examining behavioral preference for climatic conditions, characterizing the microclimate with …

Voltage-Gated Potassium Channel Dependent Mechanisms Of Cardiovascular Adaptation To Chronic Exercise., Sean Raph

Electronic Theses and Dissertations

Exercise increases cardiac workload, escalating the demand for oxygen. The myocardial vasculature responds to the greater demand for oxygen by increasing blood flow to match the needs of the heart during augmented work. Increasing blood flow requires the coronary arteries dilate (a.k.a. vasodilation); this is mediated predominantly by vascular smooth muscle cell relaxation. Vasodilation is driven through inhibition of calcium influx into vascular smooth muscle cells. The prevention of calcium influx is largely mediated by efflux of potassium via potassium channels causing membrane hyperpolarization, which in turn closes voltage-dependent (or gated) calcium channels (VDCC). Changes in vascular smooth muscle cell …

Death Of A Bacterium: Exploring The Inhibition Of Staphylococcus Aureus By Burkholderia Cenocepacia., Tiffany Brandt

Electronic Theses and Dissertations

Antimicrobial resistance is a phenomenon of increasing concern as antimicrobial overuse and misuse eliminate current therapeutic options, ushering society into a post-antimicrobial era. Antibiotic discovery and synthesis efforts are urgently needed to counter the increasing burden of antimicrobial resistance. Staphylococcus aureus is a causative agent of a variety of clinical manifestations including bacteremia, endocarditis, soft tissue infection, osteomyelitis, and device-related infections. S. aureus infection presents additional treatment challenges due to its capacity for biofilm formation, which is a mode of growth that confers protection from antibiotics and physical elimination, and the emergence of antibiotic resistant strains, including methicillin-resistant S. aureus …

Bayesian Methods For Graphical Models With Neighborhood Selection., Sagnik Bhadury

Electronic Theses and Dissertations

Graphical models determine associations between variables through the notion of conditional independence. Gaussian graphical models are a widely used class of such models, where the relationships are formalized by non-null entries of the precision matrix. However, in high-dimensional cases, covariance estimates are typically unstable. Moreover, it is natural to expect only a few significant associations to be present in many realistic applications. This necessitates the injection of sparsity techniques into the estimation method. Classical frequentist methods, like GLASSO, use penalization techniques for this purpose. Fully Bayesian methods, on the contrary, are slow because they require iteratively sampling over a quadratic …