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Integrated Control Of Colorado Potato Beetle And Potato Virus Y Using Mineral Oil, Andrew K. Galimberti

Electronic Theses and Dissertations

Colorado potato beetle (Leptinotarsa decemlineata) (CPB) and Potato Virus Y (PVY) are two of the most damaging pests attacking potato crops. CPB can cause significant defoliation to potato fields and is difficult to control using insecticides because its populations rapidly develop insecticide resistance. PVY, which is transmitted non-persistently by aphids, can result in yield loss and rejection of seed potato lots. Due to its rapid mode of transmission, insecticides are often ineffective at curtailing the spread of the virus. Thus, an integrated pest management (IPM) approach is essential for both CPB and PVY control.

Mineral oil is a …

Long-Term Sustainability Of Northern Mixedwood Management: Spatial And Temporal Aspects Of Forest Productivity, Bethany L. Munoz

Electronic Theses and Dissertations

Natural disturbances of moderate severity are common in northern temperate forests in Maine, USA. Given estimated return intervals of 575-1000 years for severe windstorms and 385-1200 years for severe fire events, few opportunities arise to evaluate high severity disturbances in northern mixedwood or northern conifer forests. This research evaluated 50-year results of clearcutting with whole-tree harvesting (WTH), stem-only harvesting (SOH), and stem-only harvesting with prescribed burning (SOHB) on growing stock, composition, and relationships among foliar and soil nutrient concentrations. At the other end of the disturbance spectrum, this research also investigated 60-year results of single-tree selection with a 10-year cutting …

Prospective Associations Of Homocysteine, Executive Function, And Depressive Symptoms, Peter J. Dearborn

Electronic Theses and Dissertations

Associations of cardiovascular risk factors, cognitive performance, and depressive symptoms have been well established. However, the directionality of these associations as well as the specificity of these associations with respect to executive function are less clear. Additionally few studies have determined whether genetic risk factors, such as apolipoprotein-E4 (APOE-E4) genotype, and age moderate the associations of cardiovascular risk factors such as homocysteine with changes in depressive symptoms and how these associations may be mediated by cognitive performance. The primary aim of this study was to analyze the bidirectional associations of a full range of cognitive domains and symptoms of depression …

Developing A Collaborative Research Program To Evaluate Fine-Scale Groundfish Dynamics In Eastern Maine, Mattie Rodrigue

Electronic Theses and Dissertations

Fisheries science conducted and used for management strategies in the Gulf of Maine (GOM) is conducted at broad spatial and temporal scales. There is a tendency for fisheries-independent monitoring programs, which play a critical role in fisheries assessment and management, to miss fine-scale dynamics, especially given the complex hydrographic structures characterizing the GOM. In New England, fishermen participating in a heterogeneous groundfish fishery within the GOM may have varied perceptions of fish abundance or distribution depending on the scale at which they participate in the fishery. Overlooking fine-scale life-history dynamics coupled with scale-mismatch in science and management may perpetuate a …

Water Chemistry Dynamics In Four Vernal Pools In Maine, Usa, Lydia H. Kifner

Electronic Theses and Dissertations

Vernal pools are small seasonal wetlands that are a common landscape feature that contribute to biodiversity in northeastern North American forests. However, even basic information about their biogeochemical functions, such as carbon cycling, is limited. Dissolved gas concentrations (CH₄, CO₂) and other water chemistry parameters were monitored weekly at the bottom and surface of four vernal pools in central and eastern Maine, USA, from April to August 2016. The vernal pools were supersaturated with respect to CH₄ and CO₂ at all sampling dates and locations. Concentrations of dissolved CH₄ and CO₂ ranged …

American Woodcock Migration Ecology At An Important Stopover, Cape May, New Jersey, Brian B. Allen

Electronic Theses and Dissertations

Migration poses risks and energetic demands to individuals that may be greater than those experienced during non-migratory periods. Most migratory birds require stopover sites to rest and recuperate energy spent during migratory flights, and stopover locations can alleviate risks and provide supplemental energy en route to the animal’s end destination. An individual’s stopover duration is contingent first on energy acquisition that is constrained by resource availability, and secondarily on environmental conditions such as weather that may facilitate or constrain continued migration. From 2010 to 2013 I conducted a radio-telemetry study of a short-distance migrant, the American Woodcock (Scolopax minor), on …

Improving Management And Conservation Of Cusk (Brosme Brosme): Habitat Distribution, Bycatch Interactions, And Conservation Practices, Jocelyn M. Runnebaum

Electronic Theses and Dissertations

Cusk (Brosme brosme) are a National Oceanic and Atmospheric Administration species of concern, currently under internal status review for the Endangered Species Act, but are considered data limited. Current concerns for cusk include: decline in abundance, increase in fishing mortality relative to survey biomass, increased patchiness in habitat, and lack of management (72 FR 10710). Future management will require an improved understanding of cusk distribution, habitat use, spatial distribution of bycatch interactions, and the impact of bycatch on the population. This study set out to evaluate changes in cusk distribution and habitat, locations and levels of bycatch, and …

Evaluating The Influence Of Stem Form And Vigor On Product Potential, Growth, And Survival For Northern Commercial Hardwood Species, Mark Castle

Electronic Theses and Dissertations

Northern hardwood and mixed-wood forest types occupy a considerable percentage of the forest landscape across the Northeastern United States and portions of eastern Canada. While capable of producing valuable saw timber and veneer products, hardwood species demonstrate a wide range of stem quality resulting from the large variety of stem forms and defects that these species can manifest. The effect of different stem forms and damage has largely not been accounted for in predictions of volume, growth, and mortality. In addition to potential bias in growth and yield applications, the lack of quantification of these features has left the …

The Paradigm Of Engagement: Integrating Social Science And Extension Outreach To Engage Beginning Family Forest Owners, Ian Anderson

Electronic Theses and Dissertations

Family forest owners own 36% of the forestland in the United States. These lands provide ecosystem services and natural resources to a broad community and management of these lands should be based on informed decisions. However, many family forest owners are unaware of conservation and stewardship options, and the number of unaware landowners may be increasing. A new cohort of beginning family forest owners (BFFO), who have acquired land in the past 5 years, has emerged. Programs designed to inform landowners about different management opportunities tend to attract only a small group of interested owners. In the following 2 phase …

Evaluating The Dissemination Of The Icook 4-H Program Using Outcome, Process, And Fidelity Measures., Tara Gould

Electronic Theses and Dissertations

The iCook 4-H Dissemination Study, conducted in five states, was a control-treatment design to test whether a newly developed program for obesity prevention for youth could be successfully implemented by community leaders with minimal researcher involvement. Community leaders were primarily Cooperative Extension educators. A dyad model was used for youth (control=9.6±0.9 years of age; treatment=9.9±0.6 years of age) and their adult main food preparers (control=38.8±5.7 years of age; treatment=39.4±7.8 years of age). A three-pronged approach to evaluation developed previously for the program was used to measure outcomes, process, and fidelity of the program. The control group, youth (n=63) and adults …

Economic And Spatial Impacts Of A Wildlife Habitat Policy On Forest Management, Karin N. Bothwell

Electronic Theses and Dissertations

Regulations protecting habitat of forest-dwelling species often impact forest management practices. Those impacts may be mutually beneficial to both wildlife and forestry or they may lead to unanticipated negative outcomes, such as an associated economic cost compared to management free from habitat regulations. One example of a regulation that impacts forest management is the zoning of winter habitat of white-tailed deer (Odocoileus virginianus) in Maine, where deer abundance has been consistently below socially desired levels in most areas of the State since the 1970s due in part to the heavy toll of severe winter weather. To mitigate winter-related mortality, the …

Attenuating The Antibody Reactivity Of The Shrimp Major Allergen (Tropomyosin) Using Food Processing Methods, Adeseye Lasekan

Electronic Theses and Dissertations

Shrimp is one of the major causes of adverse allergic reactions in both adults and children. Consumers with shrimp allergy have an immune system that is hypersensitive towards certain proteins in shrimp. The immune system of these consumers produces an antibody, immunoglobulin E (IgE), which binds to specific regions on these proteins and activates reactions leading to adverse symptoms. Most shrimp allergic consumers have IgE that binds to a shrimp myofibrillar protein known as tropomyosin. Other than avoidance of shrimp, structural modification of shrimp tropomyosin using food processing methods could influence the capacity of this allergenic protein to bind IgE. …

Lobster In A Changing Gulf Of Maine: Investigating The Temporal Impact On Molting And The Fishing Fleet, Kevin W. Staples

Electronic Theses and Dissertations

We investigated the phenological and fisheries dynamics surrounding the spring molt of American lobster (Homarus americanus, Milne Edwards 1847) in the Gulf of Maine. We created a time series from Maine Department of Marine Resources Lobster Sea Sampling data using logistic models to estimate the timing and duration of the spring molt for eastern, central, and western regions of the Maine coast. These estimates revealed substantial inter-annual variability in the timing of the spring molt for all regions and that 2012 was indeed anomalously early relative to other years. Each region experienced significantly different molt timing for any given …

Sea Lamprey (Petromyzon Marinus) As A Functional Link Between Marine And Freshwater Ecosystems, Daniel M. Weaver

Electronic Theses and Dissertations

Anadromous sea lamprey Petromyzon marinus are native to Atlantic coastal systems and serve as a functional link between marine and freshwater ecosystems. Sea lamprey spend 1–2 years in the ocean parasitizing marine vertebrates before migrating into freshwaters during the spring to spawn. There they construct nests, spawn, then die shortly afterwards. Larvae hatch, bury into fine sediments and reside in streams for generally 6–8 years, but up to 14. Larvae then undergo metamorphosis, a non-feeding period characterized by a series of physical and physiological changes. The juveniles (macropthalmia) then migrate to the ocean to begin the parasitic juvenile phase.

Historically, …

Expression Profiling Of Non-Coding Rna By Environmental Interactions In Innate Immunity, Jacob R. Longfellow

Electronic Theses and Dissertations

Cystic fibrosis (CF) is a genetic disorder that affects 30,000 people in the United States and currently has no cure. Although CF affects all of the body’s systems, it is largely characterized as a lung disease. CF is caused by a mutation in both copies of the gene for cystic fibrosis transmembrane conductance regulator (CFTR). A mutation in the CFTR gene leads to improper movement of chloride ions and water into the airways, which dysregulates the airway surface liquid volume and composition. Individuals with CF are prone to lung infections due to inefficient bacterial clearance and by the age of …

Investigating Factors Contributing To Reduced Embryo Survival In Farm Raised Atlantic Salmon, Salmo Salar L., Leeanne Thayer

Electronic Theses and Dissertations

Embryo mortality of Atlantic salmon, Salmo salar Linnaeus 1758, has been increasing for more than a decade in the State of Maine, a leading producer of this species in the United States. Increasing embryo mortality not only creates a financial bottleneck for farms but also prevents the sale of surplus eggs as an additional source of revenue. Blood and egg samples were collected at three Maine Atlantic salmon farms from female broodstock at the time of spawning over a 2-year period. Correlative factors for reduced embryo survival were investigated by measuring egg and maternal plasma concentrations of 17-estradiol (E2), 11-ketotestosterone …

Molecular And Pathological Analyses Of Three New Mouse Mutations That Affect Ear Development And Function, Cong Tian

Electronic Theses and Dissertations

This dissertation presents three new mouse models that help to study the functions of Enpp1, Atp6v1b1, and Tbx1 for ear development and function. asj (aging with stiffened joints) carries a missense mutation in the mouse Enpp1 gene. Enpp1 encodes the enzyme ENPP1 that regulate soft-tissue calcification and bone mineralization, and is associated with generalized arterial calcification of infancy and hypophosphatemic rickets in human patients. asj mutant mice show severe middle ear infection and tissue calcification, which provide a new mouse model to study otitis media and tympanoscleorosis. Atp6v1b1 encode a protein that is a subunit of the V-ATPase …

Survival, Harvest, And Drumming Ecology Of Ruffed Grouse In Central Maine, Usa, Samantha Davis

Electronic Theses and Dissertations

Understanding population dynamics and how species interact with their environment are important components for conservation and management. Ruffed grouse (Bonasa umbellus) are a widely distributed and common game bird in North America and are a considered an important economic and cultural icon in Maine. Although they are a well-studied species, there has been little research focused on ruffed grouse population dynamics and habitat relationships in Maine. My thesis aims to improve this knowledge gap by focusing on research related to survival and harvest of ruffed grouse, as well as male ruffed grouse resource selection at breeding display sites. Ruffed grouse …

Forest Products Trucking Industry In Maine: Opportunities And Challenges, Anil Koirala

Electronic Theses and Dissertations

Forest transportation from in-woods to the final point of utilization is one of the major components in forest harvesting operations in terms of economics, public visibility and safety. In many cases, the price of delivered wood products depends on the transportation distance. Transportation is also crucial in terms of ensuring the supply of demanded products on time.

Globally, road transportation being the most predominant medium for forest products transportation, majority of research are focused on this subject. These scientific researches are of diverse nature; with main emphasis on improving the supply chain issues and minimizing cost of transportation, including road …

Candida And Pseudomonas Interact To Enhance Mucosal Infection In Transparent Zebrafish, Audrey C. Bergeron

Electronic Theses and Dissertations

Polymicrobial communities exist throughout the human body and include both fungi and bacteria. During disease, cross-kingdom interactions among bacteria, fungi, and/or the immune system can alter virulence and lead to complex polymicrobial infections. The fungus C. albicans is among the most commonly isolated fungi in the context of fungal-bacterial co-infections and is often accompanied by the bacterium P. aeruginosa at a variety of sites throughout the body including mucosal tissues such as the lung. In vitro, C. albicans and P. aeruginosa have a cyclic, bi-directional, and largely antagonistic relationship, but these interactions do not account for the role of the …

Basic Vision Research With Clinical Applications And Science Education Assessments, Andrew Wilson

Electronic Theses and Dissertations

Visual Acuity (VA) examinations are one of the most commonly conducted medical assessment throughout the world. Recent advances in computer technology allows for new forms of visual assessment to be conducted. In Part I of this thesis I demonstrate the capability of an automated computer program named VISION to assess human visual acuities. Different color combinations of an object against a background emitted from a computer screen are used to examine a variety of human color vision acuities. Results indicated a large difference in acuity scores between human subjects tested with these different color combinations. A single human subject exhibits …

Breeding Ecology And Habitat Use Of Unisexual Salamanders And Their Sperm-Hosts, Blue-Spotted Salamanders (Ambystoma Laterale), Kristine Hoffmann

Electronic Theses and Dissertations

Unsexual Salamanders within the Blue-Spotted Salamander Complex carry combinations of ambystomatid genomes (those of Blue-Spotted Salamanders, Ambystoma laterale, and Jefferson Salamanders, A. jeffersonianum in Maine). They are nearly all female, breed in wetlands, and use sperm of related species to reproduce. Little is known about their ecology to guide the conservation of this unique lineage. I examined breeding site occupancy, demographics, orientation, and terrestrial habitat selection of Unisexual Salamanders in comparison to Blue-Spotted Salamanders and other amphibians. I compared statistical tests of orientation to determine which was most appropriate for pitfall data.

Unisexual Salamander occupancy at breeding sites was positively …

The Biogeographic Origins And Trophic Ecology Of Maine’S Island Red-Backed Salamanders (Plethodon Cinereus), Nikko-Ideen Shaidani

Electronic Theses and Dissertations

Island populations of terrestrial species have an increased potential, compared to mainland populations, to adapt and diverge, as these populations often are isolated with respect to gene flow from other populations and may be subjected to novel pressures. Indeed, extended isolation of individuals can elicit dramatic changes within populations and is recognized as a common driver of speciation. It is for these reasons that island populations are often a priority for conservation. Plethodontid salamanders are among the most terrestrial of Maine’s amphibians and are not tolerant of prolonged exposure to seawater, and yet, they are found on a number of …

An Analysis Of Neurogenesis In A Mouse Model Of Chemotherapy Related Cognitive Impairment, Maxwell A. Hennings

Electronic Theses and Dissertations

Cancer patients treated with adjuvant chemotherapy often experience cognitive decline following treatment. This phenomenon, often dubbed “chemo brain” or “chemo fog” is usually temporary, but for a subset of survivors, these cognitive impairments can be long-lasting (>10 years) and negatively affect patients’ quality of life, career performance, and social fulfillment. While it is unclear what neurobiological mechanisms underlie chemotherapy related cognitive impairment, the majority of the animal literature has focused on adult neurogenesis. One process important for neurogenesis is the proliferation of new neurons within the dentate gyrus of the hippocampus. It is evident that many chemotherapy agents can …

A Comparison Of Seed- And Seedling-Focused Ecologically Based Weed Management Strategies, Bryan Brown

Electronic Theses and Dissertations

Many farmers target weeds at the seedling stage, aiming to control weeds with the minimum amount of labor necessary to avoid crop yield loss. Other farmers with a more long-term, seed-focused approach aim to prevent weeds from setting seed so that emergence will be decreased in subsequent crops. These strategies likely vary in short- and long-term effects on farm ecological and economic health. In 2014–2016, I compared these strategies in a test crop of onion. Unexpectedly, due to high yields, the more labor intensive, seed-focused strategy was the most profitable. Case-study interviews of farmers who have adopted each approach indicated …

Population Ecology Of Colonially Breeding Seabirds: How Intrinsic Processes, Mediating Influences, And Individual Heterogeneity Affect Population Vital Rates, Aly Mcknight

Electronic Theses and Dissertations

Seabirds have great potential to serve as marine indicators. However, before we can interpret seabird trends with confidence, we need a better understanding of the role of intrinsic processes, mediating influences, and lifetime experience in modulating relationships between prey availability and seabird population dynamics.

Intrinsic processes, mediating influences, and seabird productivity. I assessed productivity (chicks per breeding attempt) at Black-legged Kittiwake (Rissa tridactyla) colonies in Prince William Sound, AK and managed Common Tern (Sterna hirundo) colonies in the Gulf of Maine. Both systems showed evidence of intrinsic control; factors mediating access to prey were also important.

Mediating influences, individual heterogeneity, …

Divergent Responses Of Larval And Juvenile Blue Mussels To Low Salinity Exposure, Melissa A. May

Electronic Theses and Dissertations

In this study, we compared the osmotic stress response of larval and juvenile blue mussels (Mytilus edulis) at the transcriptomic, metabolomic, and whole organism levels. Blue mussels inhabit coastal areas, where they face climate-induced reductions in nearshore salinity. Despite their ecological and economic importance, scientists do not fully understand the underlying transcriptomic and cellular mechanisms of the osmotic stress response in blue mussels or how the ability to respond to stress changes throughout development. Blue mussels spend the first weeks of life developing through several larval stages in the plankton. These early life history stages are more vulnerable …

Measuring Fertilization In Populations Of Sea Scallop (Placopecten Magellanicus): Developing And Testing Methods In The Laboratory And Field, Skylar Bayer

Electronic Theses and Dissertations

Most marine organisms are broadcast spawners, releasing their sperm and eggs into the water column. Methods of measuring in situ fertilization have proven successful with a few model species, which are reviewed in my introductory chapter. However, many commercially exploited species, such as the sea scallop Placopecten magellanicus, have been neglected. Sea scallop populations have greatly increased from fishing closures, but the mechanism behind this response is uncertain, particularly in regard to fertilization. In this dissertation I developed a methodology of measuring fertilization success and spawning events of P. magellanicus, tested it in laboratory and field settings, and …

Effects Of Dam Removal On Assemblage Composition And The Interactions Of Fishes In The Penobscot River, Maine, Jonathan Watson

Electronic Theses and Dissertations

Dams and their impoundments disrupt river habitat connectivity to the detriment of migratory fishes. Removal of dams improves riverine connectivity and lotic habitat which benefits these fishes along with resident fluvial specialist species. Restoration efforts on the Penobscot River (Maine, USA) are among the largest recently completed in the United States, and include the removal of the two lower-most dams and improvements to fish passage at several remaining barriers. Here we describe initial and potential future changes to fish communities in the Penobscot River associated with these restoration efforts.

We assessed fish assemblages in the mainstem river and several major …

Advancing Development Of Porphyra Umbilicalis As A Red Algal Model System And Aquaculture Crop, Charlotte Royer

Electronic Theses and Dissertations

The marine red alga Porphyra umbilicalis (Rhodophyta, Bangiaceae) has ideal traits to allow it to become a model organism, including its economic value, reproduction in the northwestern Atlantic through asexual neutral spores (NS), and availability of fully-sequenced nuclear and organelle genomes. Research on the bacterial component of the Porphyra microbiome is ongoing. To advance model organism development and support microbial studies, data on natural reproductive trends and early embryonic development are needed, along with a system for genetic transformation, and ways of visualizing the attached microbial community. To meet these needs, two years of phenological data were analyzed, revealing seasonal …