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2016

Electronic Theses and Dissertations

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Full-Text Articles in Life Sciences

Understanding The Impact Of Commercial Harvest On White Suckers (Catostomus Commersonii) In Maine, Megan A. Begley Nov 2016

Understanding The Impact Of Commercial Harvest On White Suckers (Catostomus Commersonii) In Maine, Megan A. Begley

Electronic Theses and Dissertations

The State of Maine issues an unlimited number of commercial permits for the harvest of White Suckers Catostomus commersonii in Maine’s inland waters. The fishery provides a necessary source of fresh lobster Homarus americanus bait to coastal communities at a time when other bait sources are scarce. The impacts of the increasing number of permits and subsequent numbers of fishermen on the white sucker population is unknown. The Maine Department on Inland Fisheries and Wildlife (MDIFW) has closed a number of waters due to concerns that overfishing and incidental catch of other fish species may occur.

In Chapter 1, we …


The Effects Of A Wild Blueberry Diet On Hepatic And Aortic Morphology In The Obese Zucker Rat, A Model Of The Metabolic Syndrome, Thomas Merrow Aug 2016

The Effects Of A Wild Blueberry Diet On Hepatic And Aortic Morphology In The Obese Zucker Rat, A Model Of The Metabolic Syndrome, Thomas Merrow

Electronic Theses and Dissertations

The goal of this study is to investigate the effect of a wild blueberry diet on pathology of the metabolic syndrome (MetS) by examining the morphological and biochemical properties of the liver and aortic tissue in the obese Zucker rat (OZR), a valid model of the MetS.

At 8-weeks of age, 16 Obese Zucker ras (OZR) and 16 lean Zucker rats (LZR) littermates were placed on either an 8% w/w wild blueberry (WB)-enriched isocaloric diet or an isocaloric control (C) diet for a duration of 8-weeks. At 16-weeks of age, the tissues of interest were harvested for the study. The …


Social Ecological Food Systems: Sustainability Lessons From Maine Dairy Networks, Julia B. Mcguire Aug 2016

Social Ecological Food Systems: Sustainability Lessons From Maine Dairy Networks, Julia B. Mcguire

Electronic Theses and Dissertations

Milk production has played an integral role in the culture, landscape, and economy of Maine’s agriculture. Maine dairy farmers have faced numerous sustainability challenges to economic, environmental, and social aspects of their industry. Like many other complex social ecological systems, the Maine dairy industry faces a gap between scientific knowledge and actionable management or policy. A cultural dichotomy exists between conventional and organic farming. Shifting the focus from this binary, metrics such as social capital may play a key role in solving sustainability issues. Difficulties arise in the governance of complex social ecological systems when the scales of assessment, management, …


Population Genetic Structure Of Softshell Clams (Mya Arenaria) With Regard To A Saxitoxin-Resistant Mutation And Neutral Genetic Markers In The Gulf Of Maine, Jennifer Phillips Aug 2016

Population Genetic Structure Of Softshell Clams (Mya Arenaria) With Regard To A Saxitoxin-Resistant Mutation And Neutral Genetic Markers In The Gulf Of Maine, Jennifer Phillips

Electronic Theses and Dissertations

The softshell clam, Mya arenaria, is a commercially important bivalve species that is found in soft-bottom intertidal habitats throughout the Gulf of Maine, USA. This species is subjected to seasonal blooms of the toxic algae Alexandrium spp., and acts as a vector for paralytic shellfish poisoning (PSP) during harmful algal bloom (HAB) events. Some clams possess a naturally occurring genetic mutation of their voltage-gated sodium channels that grants them a resistance to the paralytic effects of saxitoxin (STX) produced by Alexandrium spp. The mutation allows these individuals to continue feeding during HABs, and greatly increases their tissue toxicity through …


Shortnose Sturgeon (Acipenser Brevirostrum) Spawning Potential In The Penobscot River, Maine: Considering Dam Removals And Emerging Threats, Catherine Johnston Aug 2016

Shortnose Sturgeon (Acipenser Brevirostrum) Spawning Potential In The Penobscot River, Maine: Considering Dam Removals And Emerging Threats, Catherine Johnston

Electronic Theses and Dissertations

Dam removals from the Penobscot River in Maine restored access to freshwater habitat critical for the life cycle of endangered shortnose sturgeon. Prior to the dam removals, shortnose sturgeon spawning activity had not been documented. Instead, evidence suggested that individuals emigrated from the Penobscot River to spawn in the Kennebec complex, 140 km away. A central question of this thesis was whether spawning activity would commence in the first two years following dam removal. Consistent with pre-dam removal movement patterns determined using acoustic telemetry, the majority (78%) of tagged individuals emigrated from the Penobscot River at some point over the …


Propagation And Container Production Of The Amelanchier Spicata Complex, Gregory J. Melcher Aug 2016

Propagation And Container Production Of The Amelanchier Spicata Complex, Gregory J. Melcher

Electronic Theses and Dissertations

Amelanchier is a genus in the Rosaceae containing shrubs and trees indigenous to North America that possess traits valued by the horticulture industry. Amelanchier spicata (dwarf serviceberry), a heterogeneous complex of hybrids indigenous to eastern North America, has agricultural and ornamental merit with notable characteristics. White blossoms emerge in early spring, edible pomes ripen in the summer, and vibrant, orange foliage occurs in the fall. I investigated phenological and physiological factors influencing adventitious rooting of stem cuttings, the effects of nitrogen source on the development of seedlings grown in container culture, and phenotypic variation among seedlings of A. spicata from …


Dynamic Host-Pathogen Interactions Result In Fungal Epitope Unmasking, Alex Hopke Aug 2016

Dynamic Host-Pathogen Interactions Result In Fungal Epitope Unmasking, Alex Hopke

Electronic Theses and Dissertations

Molecular camouflage is used by a diverse set of pathogens to disguise their identity and avoid recognition by protective host receptors. The opportunistic fungal pathogen Candida albicans is a good example, as it masks the inflammatory component β-glucan in its cell wall to evade detection by the immune receptor Dectin-1. Interestingly, it has been seen that β-glucan becomes unmasked during infection in vivo, though the underlying mechanisms remained unclear. Exposure levels of this epitope may be important, as Dectin-1 mediates protection from some strains of C. albicans and alterations in the organization and composition of the Candida cell wall …


Refrigerated Shelf Life Evaluation And Effects Of Minimal Processing On Antioxidant Capacity Of Fresh Sea Vegetables From New England, Dhriti Nayyar Aug 2016

Refrigerated Shelf Life Evaluation And Effects Of Minimal Processing On Antioxidant Capacity Of Fresh Sea Vegetables From New England, Dhriti Nayyar

Electronic Theses and Dissertations

Sea vegetables (also known as seaweeds) are gaining popularity among American consumers as a new superfood. Some sea vegetable farmers in New England have begun to distribute fresh or minimally processed sea vegetables to local restaurants and to retail distributors. However, limited knowledge about quality loss and processing effects on fresh, farm-raised sea vegetables postharvest obstructs the growth of a vibrant sea vegetable industry. The objectives of this research were to: 1) evaluate the quality changes and shelf life of four fresh sea vegetables species - dulse, Gracilaria, sugar kelp and winged kelp - during refrigerated storage, 2) determine the …


Size As A Trait For Understanding The Role Of Zooplankton In The Biological Carbon Pump, Karen Stamieszkin Aug 2016

Size As A Trait For Understanding The Role Of Zooplankton In The Biological Carbon Pump, Karen Stamieszkin

Electronic Theses and Dissertations

Living organisms impact carbon transport between the atmosphere and the ocean through the biological carbon pump. Some plankton communities augment carbon export from the ocean’s surface, and are thought to have a major role in global climate. These export communities are often characterized by larger organisms that sink to depths where the carbon they contain is sequestered from the atmosphere. Zooplankton can enhance export by aggregating prey into larger sinking fecal pellets; however fecal pellet flux is a highly variable component of the biological carbon pump. Relating plankton trophic dynamics to changes in particulate carbon flux is an important step …


Biological, Behavioral And Preventative Management Of The Invasive Insect Pest, Spotted Wing Drosophila (Drosophila Suzukii Matsumura), In Maine Lowbush Blueberry (Vaccinium Angustifolium Aiton), Gabe Alnajjar Aug 2016

Biological, Behavioral And Preventative Management Of The Invasive Insect Pest, Spotted Wing Drosophila (Drosophila Suzukii Matsumura), In Maine Lowbush Blueberry (Vaccinium Angustifolium Aiton), Gabe Alnajjar

Electronic Theses and Dissertations

This research was conducted in order to identify the potential for utilization of various management techniques against the invasive Drosophila suzukii Matsumura, commonly referred to as the spotted wing drosophila (SWD), using Maine lowbush blueberry (Vaccinium angustifolium Aiton) as a model crop system. These included evaluations of three prospective approaches often considered when developing agricultural pest management programs for novel insect pests: 1) biological control through the intended release of natural enemies, in this case entomopathogenic fungi; 2) behavioral management through mass trap deployment in order to capture and kill adult SWD, and; 3) prevention through the deployment of …


Behavioral Ecology Of Landbird Migrants In A Complex And Changing Flyway System: The Gulf Of Maine, Adrienne J. Leppold Aug 2016

Behavioral Ecology Of Landbird Migrants In A Complex And Changing Flyway System: The Gulf Of Maine, Adrienne J. Leppold

Electronic Theses and Dissertations

In and around the Gulf of Maine, over 300 species of birds have been documented during migration, and tens of millions of songbirds may pass through the region on a single autumn night. Shorelines are widely documented as major migration corridors. There is ample evidence that coastal areas concentrate migrants and many species make overwater movements to and from breeding and wintering grounds. Data collected from radar, banding, and ceilometry studies in the northeast have provided us with evidence that birds migrate along the coast and make overwater movements across the Gulf of Maine and Bay of Fundy during both …


Development Of Eco-Friendly Composite Foam Boards For Thermal Insulation And Packaging Purposes Using Cellulose Nanofibrils (Cnf), Nadir Yildirim Aug 2016

Development Of Eco-Friendly Composite Foam Boards For Thermal Insulation And Packaging Purposes Using Cellulose Nanofibrils (Cnf), Nadir Yildirim

Electronic Theses and Dissertations

Reducing energy consumption is a high priority in the United States and throughout the world. Energy used to heat and cool occupied constructed facilities is of particular concern, and one of the most effective strategies is insulating the building envelope. Historically, builders used whatever material was available to fill the void between interior and exterior walls, including wool fibers, paper, and even corn cobs. Today, homes are built using foam insulation that harden when applied, blown-in loose insulation, fiberglass mats or rigid foam boards usually composed of polystyrene. Rigid foam boards are used in a variety of applications despite the …


Spruce Grouse Habitat Ecology In Maine's Commercially Managed Acadian Forest, Stephen W. Dunham Aug 2016

Spruce Grouse Habitat Ecology In Maine's Commercially Managed Acadian Forest, Stephen W. Dunham

Electronic Theses and Dissertations

Spruce grouse (Falcipennis canadensis) inhabiting the mixed coniferous-deciduous forests of the northeastern United States are at the southern extent of their range. These mixed forests are known collectively as the Acadian forest and represent the transitional zone between the boreal forest to the north and the deciduous northern hardwoods forests to the south. Often assumed to be associated with mature, unharvested forest in this region, few studies have assessed habitat relationships of the species within areas dominated by commercial forest management. We investigated the influence of stand maturity, vertical and horizontal cover, and patchiness on the occupancy and …


Breeding Season Avian Community Composition And Prey Availability In Eucalyptus And Slash Pine Plantations Of Southwestern Louisiana, Elizabeth J. Messick Aug 2016

Breeding Season Avian Community Composition And Prey Availability In Eucalyptus And Slash Pine Plantations Of Southwestern Louisiana, Elizabeth J. Messick

Electronic Theses and Dissertations

The increased demand for wood products related to industries such as bioenergy and paper has resulted in a need for a consistent supply of raw materials. Eucalyptus (Eucalyptus spp.) plantations have the potential to boost wood production for pulpwood and biomass feedstocks. Species characteristics such as rapid, indeterminate growth, coppice regrowth, resistance to disease and insects, and tolerance of a range of environmental conditions make these species successful short-rotation woody crops (SRWCs). Camden white gum (Eucalyptus benthamii), a more cold tolerant species, has made management of eucalyptus plantations viable in southern portions of the United States such …


Positional And Match Action Profiles Of Elite Women’S Field Hockey Players In Relationship To The 2015 Fih Rule Changes, Heather A. Abbott Aug 2016

Positional And Match Action Profiles Of Elite Women’S Field Hockey Players In Relationship To The 2015 Fih Rule Changes, Heather A. Abbott

Electronic Theses and Dissertations

The objective of this dissertation was to examine the action profiles of elite field hockey players in relationship to the 2015 FIH rule change. The following are major findings of the dissertation: The following are major findings of the dissertation: Study 1 – Relative action profiles before the rule change revealed that defenders work at a lower meter per minute (m/min) when compared with all other positions, and that forwards, midfielders, and screens perform similar m/min during a game. Examination of pre rule change difference from the 1st to the 2nd half play showed that elite level field hockey players …


Seasonal Perceived Training Load In Ncaa Di Men’S Soccer: Is There A Dose-Response Relationship?, Andrew A. Pustina Aug 2016

Seasonal Perceived Training Load In Ncaa Di Men’S Soccer: Is There A Dose-Response Relationship?, Andrew A. Pustina

Electronic Theses and Dissertations

The purpose of this dissertation was to determine if a there was a dose-response relationship across an NCAA Division I men’s soccer season. Specifically, this dissertation serves to: 1.) assess the validity of duration measurements that have previously been used to calculate session RPE during competitive matches, 2.) determine the degree and magnitude of change in intermittent endurance performance across a season and to observe how change in endurance relates with training load, 3.) determine the degree and magnitude of change in strength and explosiveness across a season, and to see how these strength changes relate to training load. 1.) …


The Relationship Between Strength, Power, And Sprint Acceleration In Division I Men’S Soccer Players, Christopher Bellon Aug 2016

The Relationship Between Strength, Power, And Sprint Acceleration In Division I Men’S Soccer Players, Christopher Bellon

Electronic Theses and Dissertations

The purposes of this dissertation were three-fold. The first was to identify the approximate distances characterizing early-, mid-, and late-acceleration in a population of Division I men’s collegiate soccer players. The secondary purpose was to investigate the relationships between various strength-power variables and key sprint characteristics during early-, mid-, and late-acceleration in a population of Division I men’s soccer players. The final purpose of this dissertation was to compare the spatiotemporal characteristics of “strong” versus “weak” and “more powerful” versus “less powerful” Division I men’s soccer players during early-, mid-, and late- acceleration. The following are the major findings of …


Long-Term Overstory Vegetation Responses To Prescribed Fire Management For Longleaf Pine At Big Thicket National Preserve, Deanna M. Boensch Aug 2016

Long-Term Overstory Vegetation Responses To Prescribed Fire Management For Longleaf Pine At Big Thicket National Preserve, Deanna M. Boensch

Electronic Theses and Dissertations

At the western edge of the longleaf pine (Pinus palustris) range, federal land managers have burned the forests of Big Thicket National Preserve to bring back the structure and diversity of the longleaf pine forest. In the early 1990’s, a four year study was conducted by Rice University, and the National Park Service continued monitoring the study’s fire ecology research plots. After two decades of data collection, ordination was applied to species abundance data to examine changes in vegetation communities from a variety of prescribed fire treatments and controls. The vegetation data was separated by size class to include overstory, …


Effects Of Acute Exercise On Postprandial Lipemia And Postprandial Glycemia, Stephen Decker Aug 2016

Effects Of Acute Exercise On Postprandial Lipemia And Postprandial Glycemia, Stephen Decker

Electronic Theses and Dissertations

Introduction: Moderate-intensity aerobic exercise has been shown to attenuate the rise in triglycerides in during the postprandial period, however the effects of acute bouts of high-intensity exercise on postprandial lipemia and glycemia have not been explored. The purpose of this study was to examine the effects of acute high-intensity interval training on postprandial lipemia and postprandial glycemia.

Methods: Ten healthy males participated in a randomized crossover design consisting of one high-intensity exercise session and one sedentary control session, followed by consumption of a mixed meal. Blood triglyceride and glucose concentrations were monitored following the consumption of the meal.

Results: High-intensity …


Effect Of A Recovery Supplement On Weight Lifting Performance, Muscle Fiber Morphology And Muscle Protein Accretion, Christopher B. Taber Aug 2016

Effect Of A Recovery Supplement On Weight Lifting Performance, Muscle Fiber Morphology And Muscle Protein Accretion, Christopher B. Taber

Electronic Theses and Dissertations

The purposes of this dissertation were to examine the effect of a protein and carbohydrate recovery beverage versus a placebo on weightlifting performance, its effect on muscle morphological changes and specific muscle protein accretion. The following are major finding from the dissertation: 1) Protein and carbohydrate recovery supplementation does not appear to have influence on performance measure in trained weightlifters. This finding may be associated with the short-term nature of this study and the trained population used. 2) Compared with placebo, a protein and carbohydrate beverage provided greater benefits on cross sectional area of type I and type II muscle …


Exploring The Threats Of Dams And Ocean Conditions: In-River Movements And Ocean Growth Of Atlantic Salmon (Salmo Salar) From Maine's Rivers, Lisa K. Izzo Aug 2016

Exploring The Threats Of Dams And Ocean Conditions: In-River Movements And Ocean Growth Of Atlantic Salmon (Salmo Salar) From Maine's Rivers, Lisa K. Izzo

Electronic Theses and Dissertations

Substantial declines of anadromous Atlantic Salmon Salmo salar have occurred throughout the range of the species, with many populations at the southern extent of the distribution being extirpated or endangered. While Maine is the last state in the country where adult Atlantic Salmon return to rivers each year to spawn, numbers have decreased dramatically in recent decades, with typically less than 2,000 spawners returning to all Maine's rivers combined. The complex life history of this species, which involves a juvenile freshwater phase followed by a marine phase that can last one to five years before returning to freshwater to spawn …


Production Of Acetic Acid In Kraft Pulp Mill Biorefinery Using Bi-Polar Membrane Electrodialysis, Ravikant Amogisidha Patil Aug 2016

Production Of Acetic Acid In Kraft Pulp Mill Biorefinery Using Bi-Polar Membrane Electrodialysis, Ravikant Amogisidha Patil

Electronic Theses and Dissertations

The objective of this dissertation was to develop a process for the production of acetic acid in kraft mills. Acetyl groups in hardwood can be hydrolyzed using alkali at 50 °C. The product from this process contains about 15 g/L of sodium acetate and was determined to be suitable for the production of acetic acid.

Experiments performed using aqueous sodium acetate to evaluate the ability of electrodialysis (ED) to separate and concentrate sodium acetate showed that sodium acetate can be concentrated up to 275 g/L starting with an initial concentration of 17 g/L. The transport of water with sodium and …


Relationship Between Lower Body Strength, Countermovement Jump Height, And Optimal Drop Jump Drop Height, Cameron V. Griggs Aug 2016

Relationship Between Lower Body Strength, Countermovement Jump Height, And Optimal Drop Jump Drop Height, Cameron V. Griggs

Electronic Theses and Dissertations

The purpose of this study was to understand the relationship between back squat one-repetition maximum relative to body mass (1RMrel), countermovement jump height (CMJH), and optimal drop height in drop jump (DHopt). Fifteen male participants with various sport backgrounds and training experience completed a one repetition maximum (1RM) back squat, maximum countermovement jump (CMJ), and drop jumps (DJ) from incrementally increasing drop heights to determine which drop height elicited the greatest jump height. The DHopt testing protocol was unique in that smaller increments were used to determine DHopt compared to what has been reported in literature previously. Pearson correlation coefficients …


Characterization Of Sip470, A Family 1 Lipid Transfer Protein And Its Role In Plant Stress Signaling, Timothy Ndagi Audam Aug 2016

Characterization Of Sip470, A Family 1 Lipid Transfer Protein And Its Role In Plant Stress Signaling, Timothy Ndagi Audam

Electronic Theses and Dissertations

SIP470, a putative tobacco lipid transfer protein, was identified in a yeast two-hybrid screen to interact with SABP2. SABP2 is a critical role in SA-mediated signaling in tobacco and other plants. In vitro studies using purified recombinant SIP470 confirmed that it is a lipid binding protein. In an attempt to determine its role in mediating stress responses, Arabidopsis T-DNA insertion knockout lines lacking SIP470 homolog were used for the analysis. These mutant plants were defective in basal resistance against microbial pathogens. Expression of defense gene PR-1 was also delayed in these mutant plants. Interestingly, these mutant plants were not defective …


Characterization Of Pro-Inflammatory And Anti-Inflammatory Microglia In The Anterior Cingulate Cortex In Autism Spectrum Disorder, Aubrey N. Sciara Aug 2016

Characterization Of Pro-Inflammatory And Anti-Inflammatory Microglia In The Anterior Cingulate Cortex In Autism Spectrum Disorder, Aubrey N. Sciara

Electronic Theses and Dissertations

Autism spectrum disorder (ASD) is associated with functional abnormalities of the anterior cingulate cortex (ACC), a brain area that mediates social behavior. Given evidence of a role of inflammation in ASD, markers of pro-inflammatory and anti-inflammatory microglia were studied using postmortem ACC tissues from ASD and age-matched typically developed control donors. Gene expression levels of pro-inflammatory (CD68, HLA-DRA, IL1B, NOS2, PTGS2) and anti-inflammatory (ARG1, IGF1, MRC1, PPARG) microglial genes were measured using quantitative real-time PCR. Additionally, brain sections were immunohistochemically stained for a microglial marker. Expression levels of IGF1 were modestly higher, while the expression of …


Venom Peptides Lasioglossin Ii And Mastoparan B As Escherichia Coli Atp Synthase Inhibitors, Rafiat Ajoke Bello Aug 2016

Venom Peptides Lasioglossin Ii And Mastoparan B As Escherichia Coli Atp Synthase Inhibitors, Rafiat Ajoke Bello

Electronic Theses and Dissertations

The inhibitory effects on Escherichia coli ATPase activity by two venom peptides, lasioglossin II and mastoparan B. Membrane bound F1FO ATP synthase was isolated from E. coli strain pBWU13.4/DK8 and treated with varied concentrations of lasioglossin II and mastoparan B. Lasioglossin II caused very low inhibition of ATPase activity, but the inhibition profile of mastoparan B was suggestive of an interesting biological effect. A relatively shorter total length, a smaller net positive charge, and a reduced amphipathic character of both peptides, as compared to previously tested antimicrobial peptides, may account for the limited degree of inhibition observed …


Endothelial Hspa12b Is A Novel Protein For The Preservation Of Cardiovascular Function In Polymicrobial Sepsis Via Exosome Mir-126, Xia Zhang Aug 2016

Endothelial Hspa12b Is A Novel Protein For The Preservation Of Cardiovascular Function In Polymicrobial Sepsis Via Exosome Mir-126, Xia Zhang

Electronic Theses and Dissertations

Sepsis is the most frequent cause of mortality in most intensive care units. Cardiovascular dysfunction is a major complication associated with sepsis, with high mortality rates up to 70%. Currently, there is no effective treatment approach for sepsis.

The integrity of the endothelium is fundamental for the homeostasis of the cardiovascular system. Sepsis induces endothelial cell injury which is the key factor for multiple organ failure. The increased expression of adhesion molecules and chemokines in endothelial cell promotes leukocytes infiltration into the tissue. The loss of tight junction proteins and increased permeability of the endothelial cells will provoke tissue hypoxia …


Exploring The Relationship Between Behaviour And Neurochemistry In The Polyphenic Spider, Anelosimus Studiosus (Araneae: Theridiidae), Jennifer B. Price Aug 2016

Exploring The Relationship Between Behaviour And Neurochemistry In The Polyphenic Spider, Anelosimus Studiosus (Araneae: Theridiidae), Jennifer B. Price

Electronic Theses and Dissertations

The importance of social behaviour is evident in human society, but there are both costs and benefits associated with cooperation and sociality throughout the animal kingdom. At what point do the benefits outweigh the costs, and when do selective pressures favour sociality and colonization over solitude and independence? To investigate these questions, we have focused on an anomalous species of spider, Anelosimus studiosus, also known now as the northern social spider. Throughout its broad range, A. studiosus is solitary and aggressive, but recently, colonies of cooperative and social individuals have been observed at northern latitudes. This leads to two …


Impact Of Luminance And Spatial Parameters On The Generation Of The Human Pattern Electroretinogram., Kate A. Godwin Aug 2016

Impact Of Luminance And Spatial Parameters On The Generation Of The Human Pattern Electroretinogram., Kate A. Godwin

Electronic Theses and Dissertations

The current work assessed some of the key hypotheses behind the generation of the pattern electroretinogram (PERG) response. The first of these hypotheses states that the PERG response is the result of linear cancellation of simultaneous increment and decrement retinal responses, as generated by the retinal ON- and OFF-pathways. Experiment 1 evaluated the possibility of simulating the PERG by summing the ERG responses elicited by increment and decrement flashes, and found that it was indeed possible to simulate the PERG from these responses. However, only the steady-state PERG could be modeled consistently. The second hypothesis evaluated a theory that the …


The Role Of O-Glcnacase During Heart Failure., Sujith Dassanayaka Aug 2016

The Role Of O-Glcnacase During Heart Failure., Sujith Dassanayaka

Electronic Theses and Dissertations

Global augmentation of protein O-GlcNAcylation occurs in response to a myriad of stressors and confers a survival advantage at the cellular level. This protective phenomenon has been demonstrated to mediate cardioprotection through various in vitro and in vivo studies during ischemia-reperfusion, myocardial infarction, and oxidative stress; however, relatively little is known of the regulation of protein O-GlcNAcylation. Protein O-GlcNAcylation is regulated by two antagonistic enzymes, namely, O-GlcNAc transferase (OGT) and O-GlcNAcase (OGA). Ablation of cardiomyocyte OGT, the enzyme that catalyzes the addition of O-GlcNAc to proteins, exacerbates cardiac dysfunction during infarct-induced heart failure (HF). However, little is known of the …