Life Sciences Commons^™

The Future Of Maine's Forests Under Alternative Socioeconomic, Climate And Conservation Pathways, Jianheng Zhao

Electronic Theses and Dissertations

Maine is a historically important timber supply region in North America and understanding the potential change in forestlands and their product industries affected by climate change and various socio-economic conditions can better improve the forest healthy and sustain a sustainable product industry. A statistical harvest choice model for the state of Maine was developed in chapter 1. It was estimated using a multinomial logit model of two products, under varying management intensities, and ownership classifications across varying market conditions. Results indicate that stumpage prices have a significant effect on forest landowners' harvest decisions and that the expansion of conservation land …

Evaluating Lignosulfonates Potential As Legume Hay And Silage Preservatives, Angela Yenny Leon-Tinoco

Electronic Theses and Dissertations

The aim was to screen and optimize low-cost lignosulfonates (LST) as legume silage and hay preservatives to decrease losses of DM and nutritive value due to spoilage. In experiment 1, we evaluated the effects of untreated silage (0%), sodium lignosulfonate (NaL) and magnesium lignosulfonate (MgL) applied independently at 0.5, 1, and 1.5 (% w/w, fresh basis) and INO (Pediococcus pentosaceus and Lactobacillus plantarum; 5 and 4 log cfu/fresh alfalfa g, on high moisture alfalfa (Medicago sativa L.) silage nutrient preservation. Data were analyzed as a randomized complete block design (RCBD; 5 blocks) and linear and quadratic polynomial contrasts were used …

Holistic Monitoring Of Maine Sea Lice (Lepeoptheirus Salmonis, Kroyer, 1837) Sensitivities To Therapies: Developing A Novel Assay To Examine Lice Behavior, Kathryn Liberman

Electronic Theses and Dissertations

Sea lice (Lepeoptheirus salmonis) present significant economic and animal welfare challenges to salmon aquaculture globally. Chemical delousing agents are used in many countries, with each nation eventually reporting sea lice developing reduced sensitivities to treatments. While some countries have in place sea lice sensitivity monitoring programs, that is not the case in Maine, USA. Although chemical delousing agents are not currently used in Maine, they have been used in the past and are currently used in neighboring Canadian salmon farms. Different bay management areas (BMAs) were sampled during different seasons to determine if there is a seasonal or spatial component …

Sustainable Production Of Feed For Recirculating Aquaculture Using Black Solider Flies And Microalgae, Patrick Erbland

Electronic Theses and Dissertations

The demand for high-quality, nutritious food continues to increase as human populations grow. As wild fisheries are depleted, aquaculture production is growing to meet the demand for seafood. Sustainable alternatives to wild caught fish meal are increasingly valued for aquaculture feed production. Microalgae and insect larvae are both valuable sources of fatty acids in aquaculture feed. Black soldier fly larvae, Hermetia illucens (L.) are used to convert organic waste streams into insect-based animal feeds. We tested their ability to retain alpha-linolenic acid (ALA), eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA) from feeding substrates, which has important implications for their use …

Development, Design, And Utilization Of A Reflective Based Photoplethysmography Sensor, Madeline Mazjanis

Electronic Theses and Dissertations

Plethysmography refers to the dynamic measurement of biological tissue volumes that, for example, may change due to fluctuations in blood volume. Photoplethysmography (PPG) makes use of the attenuation of light penetrating into vascular tissues to determine these changes in blood volume. Modern PPG is an optical technique involving low cost photosensors and light emitting diodes (LED), and is capable of measuring multiple biological vitals simultaneously. For example, in addition to heart rate determination, PPG devices can be used as pulse oximeters, capable of calculating the blood oxygen saturation (SpO2) through a series of simple optical calculations performed on either reflectance …

Wildlife Rehabilitation Datasets As An Underutilized Resource To Understand Avian Threats, Mortality, And Mitigation Opportunities, Michelle M. Duffy

Electronic Theses and Dissertations

Wildlife rehabilitation centers collect large datasets that focus on medical care, yet they also collect information more broadly relevant to wildlife conservation. The goal of this study was to demonstrate the potential for these datasets to be used in conservation science to better understand avian threats, mortality, and mitigation opportunities. We quantified the causes of bird admissions to rehabilitation centers within the Northeast and Midwest United States, the mortality rates during rehabilitation by admission cause, and the proportion of anthropogenic-caused admissions. Additionally, we related human population and development metrics to the number of bird admissions to better understand geographic bias …

Examining The Function Of Protein Acyltransferase Via The Dhhc Domain Of The Paz5 Protein In The Organism Dictyostelium Discoideum, George M. Stuart-Ranchev

Electronic Theses and Dissertations

Protein S-palmitoylation plays a crucial role in many biological systems. S-palmitoylation involves the post-translational attachment of palmitate to a cysteine residue through a reversible thioester linkage. S-Palmitoylation is used to modify both integral and membrane proteins, many of which are involved in intracellular trafficking, membrane localization, and signal transduction pathways. Intracellular palmitoylation is mediated by a family of protein acyltransferases (PATs). PAT mutations are associated with neurological diseases and cancer progression. Proteins in the PAT family are defined by the presence of a 51-amino acid cysteine-rich domain (CRD), which contains a highly conserved aspartate-histidine-histidine-cysteine (DHHC) motif. The …

Pyramiding Approaches For Potato Disease Resistance Breeding, Kristen M. Brown-Donovan

Electronic Theses and Dissertations

This study establishes the start of late blight genetic profiles for varieties and clones used as potato breeding material across the United States,and a Mendelian use of marker-assisted selection is employed to estimate allele dosage.

Potato is the fourth most important staple crop worldwide, with both high nutritional and economic values. Breeders seek improvements for many traits related to yield, dry matter, and surface and internal defects. Resistances to several diseases are also desired traits that breeders try to incorporate into their programs. The advent of DNA-based genetic technologies help breeding programs facilitate faster selection, including the use of marker-assisted …

Microsite Requirements For Successful Regeneration In Lowland Northern White-Cedar (Thuja Occidentalis) Forests, Jeanette Allogio

Electronic Theses and Dissertations

Declines in stands of northern white-cedar (Thuja occidentalis L., hereafter cedar) have been observed as both shifts in species composition and reductions in cedar densities, particularly those stands in lowland sites (Curtis 1946, Boulfroy 2012). While several factors inhibiting cedar regeneration have been identified, a thorough understanding of the conditions that best promote regeneration is lacking. Our objectives for the first chapter were to characterize the site conditions associated with successful regeneration in lowland cedar stands and to describe how spatial patterns of various cedar size classes relate to site preference and to regeneration dynamics. These objectives were achieved …

Live Cell Super-Resolution Microscopy Quanitifies An Interaction Between Influenza Hemagglutinin And Phosphatidylinositol 4,5-Bisphosphate, Jaqulin N. Wallace

Electronic Theses and Dissertations

Influenza virus, colloquially known as the flu, is an acute respiratory disease that infects several millions of individuals each year in the U.S. and kills tens of thousands of those infected. Yearly viral vaccines are widely available, however, due to the virus’s high mutation rate, their efficacy varies greatly. Due to the variability in vaccine efficiency against seasonal influenza, and the potential for even more pathogenic versions of influenza to emerge at any time, there is a high demand for a universal treatment option.

Influenza virus hijacks a variety of host cell components in order to replicate. The glycoprotein hemagglutinin …

Integrating Local Ecology And Human Dimensions To Understand A Tidally Dynamic Ecosystem In Downeast Maine, Gabriella Marafino

Electronic Theses and Dissertations

Coastal community resilience requires connecting people with useful information that reflects their needs and interests and empowers them to make informed marine resource decisions. In this thesis, I explore how to effectively integrate disparate data from different disciplines and sources to make information more useful and usable at federal, state, tribal, and local levels in order to support more holistic and integrated management. To accomplish this, I draw on different types of knowledge and approaches, including Western science, local ecological knowledge, traditional ecological knowledge, and citizen science, to incorporate the social perspective and community values for holistic marine resource management. …

Adsorptive Surface Modification Of Cellulose Nanocrystals To Stabilize Nutraceuticals Loaded Lipid Carriers For Food Application, Avinash S. Patel

Electronic Theses and Dissertations

Lipid carriers such as emulsions and liposomes have been widely studied as carriers for different nutraceuticals. However, lipid carriers' physicochemical instability results in the leakage of loaded nutraceuticals and the low solubility into the digestion medium, thus reducing the bioaccessibility. Cellulose nanocrystals (CNC) are nano-sized cellulose derivatives obtained after hydrolysis of cellulosic matrices that possess potential applications in functional foods and nutraceuticals. However, hydrophilicity, anionic surface potential, and poor re-dispersibility limit CNC’s applications. The primary objectives of this research were 1) to modify CNC via adsorbing polyethylene glycol (PEG) to stabilize liposomes and to study its physiochemical stability at different …

Evaluating The Current Weed Community In Wild Blueberry Fields And Ipm Strategies For Spreading Dogbane (Apocynum Androsaemifolium), Anthony G. Ayers

Electronic Theses and Dissertations

Lowbush blueberry (Vaccinium angustifolium) is Maine’s third largest crop (USDA 2020 a). From 2017 – 2019 the three seasons yield average was 27,200 tons were harvested from 19,500 acres for a value of $22,468,000 (USDA 2020 c). Lowbush blueberries are managed on a two-year cycle. Every other year, lowbush blueberry fields are pruned to the ground either through the use of a tractor mounted flail mower or a prescribed burn (Yarborough 2009). Pruning is a necessary part of managing lowbush blueberries as the second-year growth produces the highest yield but steadily declines in subsequent years (Drummond et al. …

Monarch Butterfly (Danaus Plexippus) Roost Site-Selection And Viability East Of The Appalachian Mountains, Brandon Boxler

Electronic Theses and Dissertations

The Monarch butterfly is a flagship species and pollinator whose populations have declined by approximately 85% in the last two decades. Their largest population overwinters in Mexico, then disperses across the eastern United States and Canada during April to August. Between September-December, the butterflies return south using two migratory flyways, one spanning the central United States and another following the Atlantic coast. They fly during the day and at night roost in large groups. Roosting habitat is essential to the continuation of the Monarchs’ migration, however, threats such as anthropogenic habitat disturbance and climate change potentially endanger sustainability of these …

American Eel Behavior And Survival In An Impounded River System, Matthew A. Mensinger

Electronic Theses and Dissertations

After beginning life in the Sargasso Sea, American eel enter river systems as juveniles and swim upstream in pursuit of freshwater habitat. Many encounter dams during this migration which act as barriers to upstream movement and limit eel establishment in headwater systems. Some dams have been retrofitted with fishways to improve watershed connectivity, but the individual selection imposed by these structures remains uncharacterized. We considered whether individual differences in behavior (i.e., personality) may be used to predict the propensity of juveniles to use a passage structure, suggesting that eel personality may predict access to habitat upstream of dams. Migrating, juvenile …

Assessing Predator Risk To Diadromous Fish Conservation In The Penobscot River Estuary, Lauri Leach

Electronic Theses and Dissertations

Successful conservation of pinnipeds in the northwest Atlantic has led to increasing populations of harbor (Phoca vitulina) and gray seals (Halichoerus grypus) in the Gulf of Maine. Seals are often perceived as predators and competitors for fish, and as a result, come into conflict with fisheries and fish conservation. Increasing numbers of seals have become a recent concern in the Penobscot River Estuary in Maine, as habitat restoration and diadromous fish conservation have been top priorities in this region for the past decade.

To understand how pinnipeds are responding to these efforts, as well as the risks they pose to …

Dissection Of Molecular Mechanisms By Which Human Host Factors Regulate Jc Polyomavirus Internalization, Colleen Mayberry

Electronic Theses and Dissertations

Viruses require a host cell in order to replicate. Infection and the onset of disease result from direct virus-host cell interactions. My dissertation research is focused on understanding how a common human virus, JC polyomavirus (JCPyV), activates specific host cell factors to cause infection. When people are immunocompromised, JCPyV infection may exacerbate into the onset of progressive multifocal leukoencephalopathy (PML), a fatal neurodegenerative disease. Individuals with the greatest risk for the development of PML are those living with multiple sclerosis or infected with HIV. Unfortunately 50-80% of the population is infected by JCPyV, putting individuals at risk for developing PML. …

Responses Of Juvenile Atlantic Salmon To Competition And Environmental Change: Implications For Performance In Maine Streams, Nicole C. Ramberg-Pihl

Electronic Theses and Dissertations

New England’s climate is changing faster than that of any other region in the continental United States. Over the last century, Maine has experienced an increase in annual temperature of approximately 1.48^oC along with a 15 percent increase in annual precipitation. Temperature and precipitation play vital roles in shaping the ecology of freshwater environments. Therefore, changes in regional climate could undermine the structure and stability of Maine’s freshwater systems as they currently exist.

Maine currently harbors the last wild populations of Atlantic salmon (Salmo salar) in the United States. Atlantic salmon were once abundant in Maine …

Uncertainties And Robustness In Fisheries Stock Assessment And Management: Data Processing, Modeling And Socioeconomic Aspects, Luoliang Xu

Electronic Theses and Dissertations

The main uncertainties that affect the quality of fisheries stock assessment and pose great challenges to fisheries management can stem from a wide range of sources including observation errors associated with model input data, dynamic model process errors, model structure misspecifications, and/or volatile fishery-related socioeconomic environment. Many assessment and management failures are in part attributed to inappropriate consideration of different uncertainties. For many traditional stock assessment models, the observation error is the only source of uncertainty that modelers explicitly deal with. The observation error is usually assumed to be random. The objective functions are formulated by the corresponding distributions (e.g., …

Development Of Valuable And Functional Protein-Based Food Ingredients From Invasive Green Crabs, Bouhee Kang

Electronic Theses and Dissertations

European green crabs (Carcinus maenas L.) are an invasive species unintentionally introduced from Europe to the U.S. Their predation and burrowing activities have had detrimental effects on our marine habitats, aquaculture, and commercially important fisheries. Despite the large population of green crabs, they are not commercially utilized in North America as food products. The specific objectives of my research were to: 1) determine functional properties of protein recovered from green crab by isoelectric solubilization and precipitation (ISP) for potential food application, 2) investigate the application of enzymatic hydrolysis for deriving bioactive compounds from green crab proteins and examine the …

Airborne Hyperspectral Data Application In Stress Detection Of Blueberry Fields And Ash Trees, Catherine Chan

Electronic Theses and Dissertations

Water management and irrigation practices are persistent challenges for many agricultural systems. Changing seasonal and weather patterns impose a greater need for understanding crop deficiencies and excesses (e.g. water, sunlight, nutrients) for optimal growth while allocating proper resources for prompt response. The wild blueberry industry is at heightened susceptibility due to its unique growing conditions and uncultivated nature. Early detection of stress in agricultural fields can prompt management responses to mitigate detrimental conditions including drought and disease. Remote sensing has provided timely and reliable information covering large spatial extents, while novel applications in hyperspectral data and imaging spectroscopy have shown …

Senders, Receivers, And Spillover Dynamics: Understanding Transformative Forces Of Aquaculture In The Marine Aquarium Trade, Bryce Risley

Electronic Theses and Dissertations

Industry and academic conversations on aquaculture’s role in the marine aquarium trade are often centered on production advancements, biological and reproductive constraints of concerned species, and conservation deliverables and often overlook the possible socioeconomic consequences of aquaculture production. Due attention is yet to be spent on understanding broader stakeholder sentiment on aquaculture production and the toll it may have on specialized suppliers such as those in the Sri Lankan marine ornamental fishery. Utilizing a framework derived from Coupled Human and Natural Systems, research found suppling stakeholders predominantly unable to participate in aquaculture production due to various access limitations. When viewed …

Beyond The Brain: A Study Of Α-Synuclein's Role In Bone And Adipose Tissue, Carolina A. Figueroa

Electronic Theses and Dissertations

α-Synuclein is a polypeptide encoded by the Snca gene, highly expressed in neurons, but it is also found in bones and adipose tissue. Co-expression analysis showed that Snca regulates skeletal homeostasis, and its deletion reduced estrogen deficiency-induced bone loss and weight gain. It is a major component of Lewy bodies (LB) in Parkinson’s disease (PD), leading to progressive immobilization and a range of nonmotor symptoms, including osteopenia, body composition alterations and insulin resistance. This thesis aimed to determine α-Synuclein’s intrinsic role in bone and adipose homeostasis. We discussed the PD pathophysiology emphasizing aspects of bone health and metabolism. By using …

Effects Of Salt And Garlic Concentration On The Microbial Safety, Biochemical Properties, And Sensory Acceptance Of Spontaneously Fermented Beet Kvass, Abigail Hing

Electronic Theses and Dissertations

Fermentation is the process by which primarily lactic acid bacteria (LAB), an environmentally ubiquitous group of organisms, convert carbohydrates into several byproducts, including acid, ethanol and/or gas. Often these resulting byproducts create desirable foods with unique flavor attributes and an increased inherent safety due to acidification. Vegetables such as red beetroot are suitable commodities for fermentation, due to abundant nutrient sources to sustain the LAB population. However, sufficient growth of LAB may lead to the production of harmful biogenic amines, specifically histamine and tyramine which can cause an allergic reaction and poisoning at high levels. Additionally, red beetroot is grown …

Biophysical And Stable Isotopic Profiles Of The Salmon Louse Lepeophtheirus Salmonis (Krøyer, 1837), Emma Taccardi

Electronic Theses and Dissertations

The salmon louse Lepeophtheirus salmonis is a parasitic copepod that infects wild and farmed salmonids throughout the northern hemisphere. L. salmonis represents the largest economic hurdle of the Atlantic salmon (Salmo salar) industry, with an estimated annual cost of nearly $1 billion globally due to production losses and anti-parasitic control measures. Salmon farming in Maine has existed for decades and is a critical economic driver, yet the region is underrepresented in global sea lice research. The aim of this work was to examine parasites in the context of animal trophic transfer and characterize physiological condition by quantifying the …

How Students Communicate Knowledge: Written Versus Drawn Responses To Formative Assessment Questions In An Introductory Undergraduate Marine Science Course, Christina Siddons

Electronic Theses and Dissertations

Undergraduate science education suffers from a lack of concrete instructional strategies that address real-world postgraduate skills such as visual literacy and science communication. Research within marine science education especially lags behind other, more well-researched fields such as physics or mathematics education, both of which have extensive literature addressing specific instructional strategies that instructors can implement in the classroom. Undergraduate marine science programs overlap with content areas from chemistry, physics, and biology, and provide a rich opportunity for examining how to include more authentic educational experiences in an undergraduate classroom. However, the types of assessments that are typically employed tend to …

High Pressure Processing Of Sous-Vide Lobster (Homarus Americanus) Tails, Sami Ali Humaid

Electronic Theses and Dissertations

Sous-vide and high pressure processing (HPP) are promising techniques in the development of high-quality seafood products. Lobsters are high-value seafood products that are highly susceptible to being overcooked using conventional methods, producing a tough and rubbery texture. Lobsters are usually sold either live or frozen due to their high perishability. The application of sous-vide cooking may provide evenly cooked lobster products with a succulent and juicy texture, while HPP may increase the shelf-life of lobster products without the use of additives. The objectives of this research were to: 1) evaluate the impact of three different sous-vide cooking conditions on physicochemical …

From Phocine Distemper To Avian Influenza: A Study Of Immunogenetic Diversity In Two Sympatric Pinniped Species, Alayna K. Gigliotti

Electronic Theses and Dissertations

Gray (Halichoerus grypus) and harbor (Phoca vitulina) seals are sympatric species that inhabit the North Atlantic and have been subject to mortality events from disease outbreaks, particularly phocine distemper and avian influenza virus. Across mortality events, gray seals tend to exhibit a higher survival rate, which could be explained by various ecological factors impacting rates or direction of selection in parts of the genome related to the immune system. These factors could include haul-out site density, habitat, and degree of inter/intraspecies interaction. This research aims to compare genetic diversity within the Major Histocompatibility Complex (MHC) class …

Distributions And Abundances Of The Red Tide Dinoflagellate Alexandrium Catenella In The Eastern Gulf Of Maine And Bay Of Fundy In Relation To Diatoms In June, July And August Of 2019, Kimberly Lina D'Adamo

Electronic Theses and Dissertations

A series of three oceanographic survey cruises were conducted in June, July, and August of 2019 in the northeastern Gulf of Maine and Bay of Fundy. Surface water samples were collected and analyzed for enumerations of cell densities of the dinoflagellate Alexandrium catenella in relation to cell densities of diatoms. Hydrographic profiles of temperature, salinity, and nutrients (silicate and nitrate) were also made at each station. Data were analyzed to determine if there was any statistically significant evidence of allelopathic interference imparted by diatoms that impede A. catenella. A. catenella cells were most abundant in June, reaching 6,195 cells per …

Triclosan Disrupts Immune Cell Function By Depressing Ca2+ Influx Via Acidification Of The Cytoplasm, Suraj Sangroula

Electronic Theses and Dissertations

Triclosan (TCS) is an antimicrobial agent that was effectively banned by the FDA from hand soaps in 2016, hospital soaps in 2017, and hand sanitizers in 2019; however, TCS can still be found in a few products. At consumer-relevant, non-cytotoxic doses, TCS inhibits the functions of both mitochondria and mast cells, a ubiquitous cell type. Via the store-operated Ca²⁺ entry mechanism utilized by many immune cells, mast cells undergo antigen-stimulated Ca²⁺ influx into the cytosol, for proper function. Previous work showed that TCS inhibits Ca²⁺ dynamics in mast cells, and here we show that TCS also inhibits …