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Spatial And Temporal Control Of The Kinesin Motors Kif11 And Kif22 In Mitosis, Alex Frances Thompson

Graduate College Dissertations and Theses

Mitosis requires the control of mechanical forces generated by kinesin motors to ensure equal segregation of chromosomes into two daughter cells. Two kinesins contributing to these forces are KIF11 (or Eg5), which crosslinks and slides anti-parallel microtubules, and KIF22 (or Kid), which binds to microtubules and chromosome arms. This work addresses how post-translational modifications and pathogenic mutations alter the structure and function of KIF11 and KIF22.

The homotetrameric kinesin KIF11 is subject to acetylation at lysine 146, a residue in the a2 helix of the motor domain. The effect of this acetylation was assessed at the single molecule and cellular …

Anchoring Communities Through Crisis: Enhancing Anchor Institutions’ Roles In Local Food Systems, Naomi Cunningham

Graduate College Dissertations and Theses

Anchor institutions serve as economic and social anchors for the communities they are embedded within. These mission-driven institutions often leverage their purchasing power and hiring practices to support community development. Local food purchases are one crucial way institutions support local economies and contribute to the development of robust and resilient food systems. The relationships institutional buyers establish with local farmers and intermediaries frequently require more time and energy to facilitate but result in more direct, connected, and mutually beneficial relationships, which, based on the findings of this research, are a critical source of resilience.

The COVID-19 pandemic is the most …

Drivers And Controls On Soil Carbon Storage In Temperate Forest Soils, Adam Noel

Graduate College Dissertations and Theses

Elevated atmospheric CO2 levels pose a threat the global climate stability but large amounts of carbon can be held within soils worldwide. Forests function to capture carbon and eventually, through litter inputs and decomposition, add this carbon to soil systems. This process is driven by climate, landscape conditions, forest and soil characteristics, that have complex interactions with one another across spatial scales. In this dissertation, I examine drivers of carbon contributions to the mineral soil, via litter decomposition and forest floor carbon pools, and how these contributions vary with forest composition and soil conditions. First, using data from a 10-year …

Revealing The Direct And Indirect Effects Of Climate Change On Soil Nutrient Dynamics And Forage Resources In Mountain Ecosystems, Kenna Elizabeth Rewcastle

Graduate College Dissertations and Theses

Modern climate change is already altering the structure and function ofecosystems around the world in nontrivial ways. Mountain ecosystems in particular will continue to experience a greater magnitude and rate of climatic warming than the global average, threatening the stability of key ecosystem processes like nutrient cycling as well as the supply of benefits from ecosystem services provided by mountains. While significant advancements have been made to address the direct effects of rising temperatures on nutrient cycling dynamics, our understanding of the synergies between the direct effects of warming and the indirect effects of climate change, mediated by the response …

Characterization And Manipulation Of O-Glcnacylation In Granulosa Cells Of Bovine Ovarian Antral Follicles, Abigail Marie Maucieri

Graduate College Dissertations and Theses

Glucose is widely recognized as the preferred energy substrate for metabolism by granulosa cells (GCs). Yet in most cells, 2-5% of glucose is shunted through the hexosamine biosynthesis pathway (HBP) for O-linked N-acetylglucosaminylation (O-GlcNAcylation). O-GlcNAcylation is an evolutionarily-conserved, post-translational process that modifies serine and threonine residues on a variety of proteins. O-GlcNAcylation is also considered a nutrient sensor that can regulate cellular processes such as metabolism, signal transduction, and proliferation. In this respect, O-GlcNAcylation may be similar to, and possibly mediate, AMP-activated protein kinase (AMPK) signaling and its nutrient-sensing actions. However, the occurrence of O-GlcNAcylation and its relative importance to …

Adaptive Capacity And [Un]Natural Disasters: Puerto Rican Farmers’ Adaption And Food Security Outcomes After Hurricane Maria, Luis Alexis Rodriguez-Cruz

Graduate College Dissertations and Theses

This dissertation investigates how social and natural elements of the Puerto Rican food system intertwine in the aftermath of category four Hurricane Maria, and relate to farmers’ adaptive capacity—access to assets and resources people have to navigate the changing climate. The research utilizes a mixed-methods survey that was conducted in 2018 in collaboration with the Extension Service of the University of Puerto Rico. The three article-based chapters use survey data from 405 farmer respondents to assess adaptive capacity through three different approaches that balance individual and structural dynamics in the context of disaster, where disruptions in livelihood activities reflect vulnerability …

A Global Understanding Of The Factors Facilitating Plant Invasions., R. Kirsten Tyler

Graduate College Dissertations and Theses

Globalization has resulted in the anthropogenic movement of plant species, many of which have established and become invasive in their secondary ranges. A fundamental goal in invasion ecology is to understand the factors that contribute to successful establishment and spread of invasive species on a global scale. Given the likelihood of a future with increased international connections leading to introductions of plant species, understanding why some species are successful invaders and which ecosystems are susceptible to invasion continues to be crucial to development of effective preventative policy and management strategies. Although there is a large body of literature on determinants …

Soil Invertebrates In Agriculture: Assessing Ecosystem Services, Biodiversity Impacts, And Farmer Perceptions, Eva Kinnebrew

Graduate College Dissertations and Theses

Harmonizing biological diversity and crop production is a major goal towards building more sustainable food systems. Soil invertebrates are diverse and abundant organisms in agriculture, but relatively little is known about their benefits or how agricultural management impacts them. In this dissertation, I dig into the complex interactions between agricultural land use and soil invertebrate biodiversity to better inform farmer decision-making. I find that soil invertebrate communities have major potential contributions to agroecosystems (Chapter 2) and are shaped heavily by agricultural land use (Chapters 3, 4), but remain too uncertain to contribute to farmers’ management choices (Chapter 5). First, I …

Mitochondrial Dynamics Regulation Of The Lung Epithelial Response To Complex Allergen, Sierra White

Graduate College Dissertations and Theses

Asthma is a chronic inflammatory disease of the lungs that affects roughly 25 million Americans, costing the United States upwards of $80 billion annually in management and economic loss. The airway epithelium, which serves as the first line of defense against insults in the lung, are now appreciated as key contributors to initiation of this disease. A key regulator of the epithelial response to allergens and other inhaled irritants that can induce an allergic asthmatic response is the mitochondria. During an allergic response, the airway epithelial energy requirement changes, and mitochondrial function is altered, enhancing production of reactive oxygen species, …

Hemp In The United States: An Analysis Of Policy And Consumption, Amanda Falkner

Graduate College Dissertations and Theses

As highlighted by its history, the association between hemp and marijuana has proven to be a barrier to success for industrial hemp production for decades. Once a prevalent agricultural crop in the United States, prohibitive legislation discouraged its production and formally made hemp an illegal crop in 1970. Consequently, hemp and its myriad applications remained underutilized by the United States for over forty years. It wasn’t until the 2014 Farm Bill that hemp production was reintroduced as an option for farmers. This hemp hiatus has created the need for interdisciplinary research in order for the market for the crop to …

Building A Learning Healthcare System: A Path To Optimizing Big Health Data To Inform Clinical Care Decisions, Danne Charlotte Emily Elbers

Graduate College Dissertations and Theses

The explosive growth of data and computing power of the last decades has had large impacts on a myriad of domains, not in the least on one of society’s most complex systems: healthcare. In this work, a version of the resulting Learning Healthcare System (LHS) is explored and elements of it have been implemented and are in use at the Department of Veterans’ Affairs today. After an overview of what a LHS is and what it could be once executed in its full form, the chapters will describe in detail some of the individual elements and how they address cogs …

Evolution Of Drought And Low Temperature Responses In Temperate Pooideae Grasses: Timings, Determinants, And Intersections, Aayudh Das

Graduate College Dissertations and Theses

Anthropogenically-mediated rises in atmospheric CO2 and global average temperatures is leading to increasingly severe drought and extreme weather events, the latter including unseasonal bouts of low and high temperatures. In order for plant breeders and conservation biologists to predict future responses to global warming, they must understand the ecological and evolutionary processes that shaped plant tolerance to stressful environments in the past. This is particularly true for grasses (Poaceae) that dominate approximately one-third of the Earth's vegetative cover, live in some of the world's harshest terrestrial environments, and are tremendously important, both ecologically and economically. One of the largest subfamily …

Climate Adaptive Forest Management In The Northeastern Us: Social And Ecological Motivations, Barriers, And Responses Of Rural And Urban Foresters, Teresa Mcgann

Graduate College Dissertations and Theses

This project examines how foresters in a diversity of professional contexts perceive and respond to global change in the northeastern United States, with the goal of supporting foresters in broadening and deepening their use of climate adaptive strategies. Based on qualitative analysis of 32 in-depth semi-structured interviews with urban and rural foresters (n = 15 and n = 17, respectively) across New England and New York, a summary is presented of the i) important environmental drivers of adaptation; ii) commonly employed adaptive practices; iii) significant barriers to adaptation; and iv) approaches to working through named barriers. According to the motivations, …

Diversity And Distribution Of The Malaria Parasites (Genus Plasmodium) Of The Common Loon (Gavia Immer) And Of Vermont Mosquitoes, Alyssa Neuhaus

Graduate College Dissertations and Theses

The emergence of infectious diseases has become an urgent concern for human and wildlife populations alike. Malaria parasites (genus Plasmodium), which are transmitted by mosquitoes, are major pathogenic disease agents in human and wildlife populations with numerous non-exclusive factors, including climate change and range shifts, acting to increase their threat. The malaria parasites that infect the Common Loon (Gavia immer) serve as an ideal system for studying emerging infectious disease threats with warming temperatures as the Common Loon is a northerly distributed, immunologically and evolutionary naïve species and of conservation concern across parts of its breeding range. I investigated the …

Thyroid Hormone Receptor Beta Inhibits Pi3k Signaling And Glycogen Metabolism In Anaplastic Thyroid Cancer, Cole Davidson

Graduate College Dissertations and Theses

Thyroid cancer is the most common endocrine malignancy, and the global incidence has increased rapidly over the past few decades. While differentiated thyroid cancers often respond to standard therapies, there are no durable long-term treatment options for anaplastic thyroid cancer (ATC). The limited treatment options highlight a need for a deeper understanding of the molecular signaling in these aggressive tumors for development of more effective therapies.Non-steroidal nuclear receptors, such as thyroid hormone receptors (TRs), are an emerging class of therapeutic targets and tumor suppressors in thyroid and other cancers.Loss of expression of the tumor suppressor thyroid hormone receptor beta (TRβ) …

Implications Of Population Genetics And Physiological Responses On The Conservation Of Moose (Alces Alces Americana), Elias Rosenblatt

Graduate College Dissertations and Theses

Wildlife populations around the globe are facing numerous, complex challengesto their persistence, yet conservation efforts are hindered by limited information about these populations and the anthropogenic pressures they face. North American moose (Alces alces americana), despite being of ecological, cultural, and economical importance, inhabit remote landscapes, making population monitoring difficult. At the same time, many moose populations, including in Vermont and eastern North America, have experienced recent declines mainly due to winter tick (Dermacentor albipictus) epizootics. Anthropogenic landscape change and climate-mediated pressures pose future challenges for moose across the southern extent of their distribution. Though impacts of winter tick infestation …

Communicating During Widespread Systematic Noise Reduction Amid Covid-19 Lockdowns: A Tale Of Two Marine Vertebrates In The Archipelago Of Bocas Del Toro, Panama, Emma Gagne

Graduate College Dissertations and Theses

Ocean soundscapes have been changing at an unprecedented rate due to the increase of human presence and associated boat noise. The physical properties of water allow sound to travel quickly with little degradation, leading to the pervasiveness and intensity of anthropogenic noise. For animals that rely on sound to communicate, this noise poses a threat to fitness and success by ‘masking’ their signals. As such, animals must find ways to be heard above the noise. Additionally, noisy environments have been shown to cause stress, which can have detrimental impacts on animal health. In recent years, various studies have shown that …

Whistle Repertoire And Structure Reflect Ecotype Distinction Of Pantropical Spotted Dolphins In The Eastern Tropical Pacific, Manali Rege-Colt

Graduate College Dissertations and Theses

The pantropical spotted dolphin in the Eastern Tropical Pacific (ETP) is found in two genetically and phenotypically distinct ecotypes, coastal and offshore. These habitats have distinct acoustic characteristics and sound fields, which can lead to the evolution of distinct acoustic communication. Whistles are tonal sounds widely used by dolphins as they mediate species and individual recognition and social interactions. Here we study the intraspecific variation of pantropical spotted dolphin ecotypes in their whistle acoustic structure and repertoire. To compare spotted dolphin whistle repertoires, we used recordings obtained from boat-surveys throughout the species distribution in the ETP. Random forest classification performed …

Building Relationships And Resilience: Local Food Systems In Vermont And New England During The Covid-19 Pandemic And Beyond, Claire Whitehouse

Graduate College Dissertations and Theses

This thesis brings together two studies of local food systems in Vermont and New England. The first study focuses on the experience of Vermont local food businesses during the Covid-19 pandemic by combining two surveys conducted in the first half of 2021: one of foodservice operations that procure food locally and one of Vermont farms that sell directly to consumers. We analyzed descriptive statistics, open responses, and conducted Kruskal-Wallis rank sum tests to assess which factors were related with business’ financial status before and since the pandemic. Pre-pandemic financial status was related with business type, whether the business went on …

Providing New Insights On Sarracenia Purpurea’S Stoichiometry, Morphology, Obligate Invertebrates, And Plankton Communities In Response To N And P Deposition., Lindsey Ann Pett

Graduate College Dissertations and Theses

For the past century, inputs of nitrogen, phosphorus, and other nutrients to aquatic ecosystems have been chronically elevated by human activities. Nutrient loading occurs at multiple spatial scales, from the discharge of wastewater into individual river drainages to atmospheric inputs at the continental scale caused by the burning of fossil fuels and use of synthetic fertilizers. Ecosystem components such as producer or consumer populations may respond stoichiometrically, either by actively regulating nutrient uptake or passively absorbing nutrients from their altered environment. Ecosystems may also respond to elevated nutrients through changes in species richness, species composition, abundance, or biomass, and these …

Characterizing The Interaction Of Polymerase Θ Helicase-Like Domain With Dna, Scott Vanson

Graduate College Dissertations and Theses

DNA damaging events occur every day in every cell of all living organisms andsome may result in double-stranded breaks (DSB). Human DNA polymerase θ (Pol θ) is a large, 290 kDa DNA repair enzyme and is the only known protein to contain both a polymerase domain and a helicase-like domain (HLD) as one molecule. Pol θ is the key mediator of the error-prone DSB repair pathway, Theta-mediated End Joining. This enzyme has been identified as a potential therapeutic target as it may be conferring a survival advantage to subsets of homologous recombination (HR)-deficient cancers, which display elevated expression levels of …

Ghgs From Bmps: Examining The Factors That Mediate Soilborne Greenhouse Gas Emissions From Agricultural Best Management Practices, Sarah Brickman

Graduate College Dissertations and Theses

Agricultural best management practices (BMPs) promote soil health and achieve multiple positive environmental outcomes. However, practices that are intended to solve one environmental challenge may have unintended climate impacts, therefore presenting a potential tradeoff. For example, manure injection is a BMP that can reduce runoff and nitrogen loss as ammonia gas (NH3) but can increase N2O and CO2 emissions compared to manure broadcast application. This thesis explores how CO2 and N2O emissions from manure injection compare to other soil fertility practices as well as the conditions that may enhance or reduce these greenhouse gas (GHG) fluxes. First, during a two-year …

The Impact Of Nitric Oxide On Dendritic Cell Metabolism, Julia Priscilla Snyder

Graduate College Dissertations and Theses

Dendritic cells (DCs) are sentinel immune cells capable of directly sensing and responding to pathogens. Upon pathogen recognition, DCs undergo a process of activation that allows them to participate in the proinflammatory response at the site of infection and to initiate the adaptive immune response through antigen presentation to T cells. Because activated DCs serve as the critical link between innate and adaptive immunity, modulating DC activation could be a powerful tool in various clinical contexts such as vaccine design. DC activation is accompanied by widespread changes in metabolism including the rapid upregulation of glycolysis, which is sustained in DCs …

Elements Of Biocontrol Strategies For Pheretimoid Earthworms, Maryam Nouri-Aiin

Graduate College Dissertations and Theses

Jumping worms (Megascolecidae) in the pheretimoid complex, have raisedconsiderable environmental concerns with conservationists, ecologists, policy makers, and the public. Their impacts on North American forests and high density is distinct from earthworms in other families. Most of the infested forests are near horticultural settings. Practicable options to manage their dispersal into forests do not exist. This dissertation examines the potential of an entomopathogenic fungus to control them in horticulture. It also investigates major barriers to managing their spread and studying their ecology including species identification, phenology, and genetic diversity. First, to discover the best time to apply biocontrol agents, I …

The Effect Of Amphibian Host Ecology And Evolution On The Pathogen Dynamics Of Ranavirus, Lauren V. Ash

Graduate College Dissertations and Theses

Emerging infectious diseases threaten amphibian species around the globe. Ranavirus (Family: Iridoviridae) is associated with the majority of amphibian deaths in North America, with some species exhibiting mass mortality events in short periods of time. In contrast, some amphibian species show the capacity to resist or tolerate infection. Resistant individuals exhibit reduced infection intensity, while tolerant individuals display reduced fitness effects given the infection intensity. My research focused on how amphibian host dynamics at community, population, and individual-level scales relate to the wide variation in Ranavirus prevalence and severity. Through my work, I documented the first reports of Ranavirus in …

Short- And Long-Term Impacts Of Forest Management In Response To The Invasive Emerald Ash Borer In New England Forests, Hanusia Higgins

Graduate College Dissertations and Theses

As non-native forest pests disperse across the United States, the emerald ash borer, Agrilus planipennis (EAB), has emerged as one of the most costly and destructive invaders. In response to EAB, forest management practices, including pre-salvage logging, "phloem reduction" (large ash removal), and strategies to improve future ash regeneration, have been implemented to meet economic, ecological, cultural, and safety objectives. Although many studies have quantified the impacts of EAB on mortality of ash trees (Fraxinus spp.), less is known about the short- and long-term ecological impacts of forest management in response to this pest. In summer 2020, we measured forest …

Experiences Participating In Federal Nutrition Assistance Programs During The Early Months Of The Covid-19 Pandemic: A Mixed Methods Study In Vermont, Emma Haven Spence

Graduate College Dissertations and Theses

For many Americans, the impacts of the COVID-19 pandemic have extended far beyond its overt health risks, spanning from economic shocks to new social realities. Elevated rates of both novel and continued food insecurity during the pandemic have been well-documented, and this burden has not been equally shared. Examination of food insecurity at the present moment offers a unique opportunity to give voice to those affected during this unprecedented time and understand the ability of existing social services to meet increased needs. This research aims to delve into the experiences of individuals at risk for food insecurity. Specifically, (1) to …

Spiny Spiders And Spiny Trees: Molecular Phylogenetics And Biogeographic Reconstruction Reveal History Of Recurrent Overwater Dispersal Events, Single-Island Endemics, And New Species Of Caribbean Micrathena (Araneae: Araneidae), Lily Kay Shapiro

Graduate College Dissertations and Theses

Elucidating the processes responsible for the provenance of taxon biodiversity on islands can help us to understand macroevolutionary mechanics in addition to specific organismal histories. Current species distributions are a result of an admixture of both abiotic (i.e. geologic) and biotic (i.e. dispersal capability, speciation and extinction rates) factors. The heterogeneous tectonic histories and local ecological differentiation among islands within the Caribbean contribute to high levels of endemicity and diversity. Differential historical biogeographic processes, namely vicariance (physical separation of populations by barriers) or long-distance dispersal, represent hypotheses to explain current distributions of species on islands resulting from colonization followed by …

Drought Tolerance In Native And Invasive Populations Of The Centaurea Jacea Hybrid Complex, Zoe Portlas

Graduate College Dissertations and Theses

Introduced plants face many ecological and evolutionary challenges when establishing in a new range, such as strong abiotic stressors and potentially novel selective environments. One such abiotic stress is water availability, which is a strong selective force shaping physiological and phenological traits that enable plants to tolerate or avoid drought stress. Despite the challenges of establishing in a new range, thousands of species have become invasive in recent centuries. Two hypotheses that may explain how a species is able to withstand stress in its introduced range are preadaptation, which posits that species are adapted to similar environments in their native …

Defining Regional Lung Extracellular Matrix Composition: Implications In Disease And Repair Following Injury, Evan T. Hoffman

Graduate College Dissertations and Theses

Chronic obstructive pulmonary disease (COPD) and idiopathic pulmonary fibrosis (IPF) are chronic lung diseases with significant worldwide impact and poor end-stage prognoses. Despite both diseases differing greatly in pathology, both COPD and IPF are hallmarked by drastic alterations to the extracellular matrix (ECM) within distinct anatomical lung regions. These alterations negatively impact cellular regeneration, and subsequently, lung homeostasis, physiology, and repair following injury. Whole decellularized lungs, stripped of cellular material while retaining lung ECM structure and composition, have previously provided complex models for both high-throughput proteomic evaluation of lung ECM as well as ex vivo culture models to study the …