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Cortical Stimulation Mapping Of Heschl’S Gyrus In The Auditory Cortex For Tinnitus Treatment, Austin Huang

CMC Senior Theses

Tinnitus is the perception of sound in the absence of an actual sound stimulus. Recent developments have shifted the focus to the central nervous system and the neural correlate of tinnitus. Broadly, tinnitus involves cortical map rearrangement, pathological neural synchrony, and increased spontaneous firing rates. Various cortical regions, such as Heschl’s gyrus in the auditory cortex, have been found to be associated with different aspects of tinnitus, such as perception and loudness. I propose a cortical stimulation mapping study of Heschl’s gyrus using a depth and subdural electrode montage to conduct electrocorticography. This study would provide high-resolution data on abnormal …

Methods To Improve The Remediation Of Polycyclic Aromatic Hydrocarbons (Pahs) In Aerobic And Anaerobic Environments, Brian Wartell

Dissertations

Oil spills occur regularly in terrestrial environments and crude oil can contain many compounds that are highly resistant to degradation. Among these compounds are high levels of polycyclic aromatic hydrocarbons (PAHs) which are not only toxic but can also be carcinogenic and/or mutagenic. The first chapter of this dissertation includes an extensive review chapter on the variables affecting the anaerobic degradation of hydrocarbons, with a particular focus on PAHs. Electron acceptors, electron donors, temperature, salinity, pH all play key roles in determining the possibility effective of effective degradation occurring. Thus, by addressing solutions, such as biostimulation, improving environmental variables for …

Functionalized Carbon Nanotubes In Hydrophobic Drug Delivery, Kun Chen

Dissertations

The direct incorporation of carboxylated carbon nanotubes (f-CNTs) into hydrophobic drug particles during their formation via anti-solvent precipitation is presented. The approach is tested using two drugs namely antifungal agent Griseofulvin (GF) and antibiotic Sulfamethoxazole (SMZ) that have very different aqueous solubility. It is observed that the f-CNTs dispersed in the water serve as nucleating sites for crystallization and are readily incorporated into the drug particles without altering crystal structure or other properties. The results show that the hydrophilic f-CNTs dramatically enhance dissolution rate for both drugs. The increased degree of functionalization leads to higher hydrophilicity and therefore faster dissolution …

Polya Db3: A Database Cataloging Polyadenation Sites(Pas) Across Different Species And Their Conservation, Ram Mohan Nambiar

Theses

Polyadenation is an important process occurring in the messenger RNA that involves cleavage of 3 end nascent mRNAs and addition of poly(A) tails. For this thesis,I present PolyA DB3 ,a database cataloging cleavage and polyadenylation sites (PASs) in several genomes specifically for human,mouse,rat and chicken. This database is based on deep sequencing data. PASs are mapped by the 3’ region extraction and deep sequencing (3’READS) method, ensuring unequivocal PAS identification. Large volume of data based on diverse biological samples is used to increase PAS coverage and provide PAS usage information. Strand-specific RNA-seq data were used to extend annotated 3’ ends …

Evaluation Of Fermentation At 40°C And 30°C For Cost Effective Lignocellulose To Lipid Conversion, Kyle M. Macewen

Graduate Masters Theses

As the world population continues to grow, the demand for energy will continue to rise. Biofuels have become an attractive alternative to replace fossil fuels as a clean and renewable source of energy. The six- and five-carbon sugars contained in lignocellulosic plant biomass is the largest carbohydrate source in the world, and a key feedstock for sustainable biofuel production. The conversion of lignocellulose to lipids is done by using oleaginous yeast as a biocatalyst. Recently, Arxula adeninivorans has become a yeast of interest because of its unique properties. These include its unusual metabolic flexibility which allows it to utilize a …

An Acoustic Monitoring Method For Assessing River Dolphin Presence And Changes In The Context Of Anthropogenic Development, Charles A. Muirhead

Graduate Masters Theses

Populations of river dolphins throughout Asia are in decline as a direct result of intensified anthropogenic activity along river systems. Water development projects, land use change, contamination, and intensified fishing practices are known factors contributing to the probable extinction of the Yangtze river dolphin (Lipotes vexillifer) and declining populations of the South Asian river dolphin (Platanista gangetica spp.), Irrawady dolphin (Orcaella brevirostris), and finless porpoise (Neophocaena a. asiaeorientalis). Although not yet as extensive, river system development in South America is following a similar path as that of Asia, with impacts on dolphin species likely to follow. Currently, the Amazon river …

Application Of Graphical Models In Protein-Protein Interactions And Dynamics, Amir Vajdi Hoojghan

Graduate Doctoral Dissertations

Every organism contains a few hundred to thousands of proteins. A protein is made of a sequence of molecular building blocks named amino acids. Amino acids will be referred to as residues. Every protein performs one or more functions in the cell. In order for a protein to do its job, it requires to bind properly to other partner proteins. Many genetic diseases such as cancer are caused by mutations (changes) of specific residues which cause disturbances in the functions of those proteins.

The problem of prediction of protein binding site is a crucial topic in computational biology. A protein …

Intraguild Predation: Interactions Between Predators, Pathogens, And Their Shared Resources In Crop Pest Communities, Andrew Jason Flick

LSU Doctoral Dissertations

Crop pest management requires an understanding of the complex interactions among pest species that potentially damage crop yield and species that may be crucial for controlling pest species outbreaks. For example, predators, parasitoids, and pathogens are constantly interacting via their shared prey or hosts. Predators may prefer infected prey, which can be easier to catch; however, infected prey may be less nutritious or even lethal for predators. These interactions then dictate the short-term dynamics of host and pathogen as well as between prey and predator. "How these dynamics change as the species in the system change either empirically or theoretically?" …

Eavesdropping On Gulf Of Maine Cetaceans In The Vicinity Of Mount Desert Rock, Christopher James Tremblay

Electronic Theses and Dissertations

Passive acoustic monitoring, the recording and analysis of biological sound, is a standard method of research into the distribution and behavior of cetaceans worldwide. Acoustic monitoring is reliant upon a thorough reference catalog of species vocalizations and an understanding of the temporal and geographic parameters in which vocalizations occur. This study combined a standard cetacean passive acoustic monitoring survey with a concurrent visual survey at a known baleen whale summer feeding ground to determine the annual species and vocal composition, compare species detection rates using each method, and identify and attribute novel vocalizations to species. The survey took place at …

Assessing The Upper Critical Limit Of The Thermoneutral Zone In Laboratory Mice, Teumbo Ngunte

Electronic Theses and Dissertations

Endothermic organisms such as mammals and birds rely on high energy budgets to regulate body temperature. Many studies have previously investigated the thermo-regulation of mammals under the lower critical temperature of the thermoneutral zone, yet our knowledge in determining the upper critical limits is still scarce. As an endotherm, lab mice (Mus musculus) are perfect models to determine the cost to maintain constant body temperature as ambient temperature increases. The upper critical temperature of the thermoneutral zone of this species has been estimated to be above 32°C and below 34°C. By utilizing different genetic backgrounds of lab mice in this …

Providing Experimental Evidence For Mouse Telomerase Reverse Transcriptase As A Novel And Unique Adult Neural Stem Cell Marker, Caroline Dean Curtis

Electronic Theses and Dissertations

With the prevalence of neurodegenerative pathologies in our society today it is imperative that we begin to look at novel approaches to the underlying problem of dying neurons that are not replaced. Adult neural stem cells exist naturally and could potentially be manipulated into targeted repair of damaged brains, given substantial research. The first step in this process is to find a way to specifically mark the earliest subset of these cells, the quiescent adult neural stem cells. Here we provide evidence for the existence of a novel and unique qANSC marker in mouse telomerase reverse transcriptase (mTERT). mTERT has …

Characterization And Functional Rescue Of Congenital Muscular Dystrophy With Megaconial Myopathy In A Mouse Model Of The Disease, Ambreen A. Sayed

Electronic Theses and Dissertations

Congenital muscular dystrophy with megaconial myopathy (MDCMC) is an autosomal recessive disorder characterized by progressive muscle weakness and wasting. Megamitochondria in skeletal muscle biopsies and cognitive impairments in MDCMC patients are observations exclusive to this type of muscular dystrophy. The disease is caused by loss of function mutations in the choline kinase beta (CHKB) gene which results in dysfunction of the Kennedy pathway for the synthesis of phosphatidylcholine (PC). A rostro-caudal muscular dystrophy (rmd) mouse with a deletion in the Chkb gene resulting in MDCMC-like symptoms has been reported by our lab. In order to test if the rmd mice …

Effects Of Increasing Temperature And Acidification On The Growth And Competitive Success Of Alexandrium Catenella From The Gulf Of Maine, Drajad Seto

Electronic Theses and Dissertations

The increases in ocean temperature and pCO2 due to climate change are projected to affect the growth and future prevalence of Harmful Algal Blooms (HABs) in nearshore waters, but systematic studies on the effects these climate drivers have on harmful algal species are lacking. In particular, little is known about how future climate scenarios will affect the growth of the toxic dinoflagellate Alexandrium catenella, which produces the toxins responsible for paralytic shellfish poisoning (PSP) that threaten the health and economy of coastal communities in the Gulf of Maine. I examined growth responses of A. catenella and two other naturally co-occurring …

Developing Animal Feed Preservatives From Paper Mill Byproducts, Diana Carolina Reyes Gomez

Electronic Theses and Dissertations

Our objectives were to evaluate the antifungal properties of technical lignins against 3 molds and 1 yeast causing hay spoilage, and for their ability to preserve alfalfa hay nutritive value. In experiment 1, 8 technical lignins and propionic acid (PRP; positive control) were tested at a dose of 40 mg/mL. The experiment had a randomized complete block design (RCBD, 4 runs) and a factorial arrangement of 3 molds × 10 additives (ADV). The effects of ADV on the yeast were also evaluated with a RCBD. Across fungi, sodium lignosulfonate (NaL) and PRP were the only treatments with a 100 ± …

The Infection Dynamics Of Sea Lice On Atlantic Salmon (Salmo Salar) In Cobscook Bay, Maine, Usa, Catherine Anne Frederick

Electronic Theses and Dissertations

Sea lice (Lepeophtheirus and Caligus spp) are parasitic copepods that infect the external surfaces of fish hosts. Salmon lice (L. salmonis) outbreaks are commonly reported by operations in Canada, Norway, Scotland, Ireland, and the United States and are a primary concern in aquaculture because of their fish health and economic impacts. When farmed fish mortalities and treatments are accounted for, annual losses from sea louse infestations exceed $300,000,000 (Costello 2009). Farms experiencing sea lice infections risk on-site re-infection and transmission to wild populations and other farms that are hydrographically connected. In Maine, Atlantic salmon farms are located in the northeast, …

Small Rna Mgrr Regulates Sensitivity Of Escherichia Fergusonii To Oxidative Stress, Austin Paul Wright

Dissertations and Theses

Non-coding small RNAs (sRNAs) are integral to post-transcriptional gene regulation in bacteria. The function of an sRNA is dependent on both secondary structure and the sequence of its unstructured seed region. The sRNA seed region typically base-pairs with target mRNAs to down-regulate the expression of target genes by blocking the ribosome-binding site or by promoting RNase-mediated degradation of the sRNA-mRNA complex. sRNAs have also been shown to increase expression of target genes by releasing RNA secondary structures that block ribosome-binding sites. Selective pressure to maintain sRNA function conserves the sequence of the sRNA seed region, but mutations in mRNA sequences …

Phenotypic And Transcriptomic Characterization Of Colonial Phase Variation In The Cholera Pathogen Reveals A Novel Smooth Biofilm-Defective Form, Bliss Nicole Lambert

LSU Doctoral Dissertations

Biofilm formation, through the production of Vibrio polysaccharide (VPS), greatly enhances the environmental fitness and pathogenic success of Vibrio cholerae. As a result of phase variation, V. cholerae can switch from a smooth form to rugose, whose cells produce excess VPS, resulting in highly structured biofilms and greater resistance to stress. To further characterize the reversible process of phase variation, we isolated three colonial lineages. Each lineage began with a smooth parent, N16961, and contained a rugose variant derived from the parent, N16961R, as well as a smooth revertant of the rugose, N16961SD. We found clear phenotypic and transcriptomic …

Modeling Human Cancer Therapy Response In Patient Derived Xenografts, Joan Malcolm

Electronic Theses and Dissertations

Patient‐derived xenografts (PDXs) generated by implanting human tumor tissue into a transplant compliant mouse host have been of increasingly importance to preclinical development and have been demonstrated to have advantages compared to cancer cell lines and cell‐line xenografts (CLX) for modeling therapeutic responses in cancer. Nevertheless, many open questions remain regarding the relationship between study design factors and classification of treatment response and the molecular fidelity of tumors passaged in PDXs relative to the original patient tumor(s). The research described in this dissertation addresses both of these significant issues related to the use of PDXs as a tool for modeling …

Multi-Tactic Ecological Weed Management In A Changing Climate, Sonja K. Birthisel

Electronic Theses and Dissertations

Climate change is expected to impact weed communities in Maine, and the efficacy of tools and tactics farmers use to manage them. Through seedbank sampling and surveys of Maine organic farms, we identified currently rare weeds that are known to be especially abundant or problematic in warmer areas of the USA and might therefore represent an emerging agronomic risk. Many ecological weed management strategies that focus on depleting the weed seedbank are expected to remain effective in a changing climate, and become increasingly important as efficacy of cultivation and some herbicide applications diminish or become more variable. Through field experiments, …

Pyrrolo[2,3-D]Pyrimidine Classical Antifolates For Targeted Cancer Chemotherapy- Applications Of Bioisosteric And Regioisomeric Substitutions For Improved Tumor-Selectivity And Potency, Manasa Punaha Ravindra

Electronic Theses and Dissertations

In 2018, it is estimated that 1,735,350 new cases of cancer and 609,640 deaths from the disease will be diagnosed in the United States alone. Conventional chemotherapy is by far the most successful category of clinical oncology, having cured (complete remission (CR), without return) or provided clinical benefit to millions of people. However, since its earliest discovery, the major causes of failure of conventional cancer chemotherapy have been dose-limiting toxicities and development of resistance. There is a desperate ongoing search for new cancer therapies as tumor-targeted agents (without harming normal cells or tissues) with low propensity for the development of …

Characterization Of G-Protein Coupled Receptors In Pain, Depression And Anxiety, Neil Lax

Electronic Theses and Dissertations

Chronic pain and major depressive disorder are widespread conditions in the world. Interestingly, these conditions often occur comorbidly, with each individual disease amplifying the symptoms of the other. A significant amount of preclinical research in pain and depression focuses on G-protein coupled receptors (GPCRs), implying that GPCRs may be useful in treating this comorbidity. Our efforts have sought to characterize several poorly understood GPCRs, including the serotonin receptor subtypes 2C and 7 (5-HT2CR and 5-HT7R) and metabotropic glutamate receptor 5 (mGluR5), along with more well-known GPCRs such as the mu opioid receptor (MOR), and the role that they play in …

Harnessing The Anopheles Microbiome To Conditionally Express Anti-Plasmodial Effectors During The Blood Meal, Jackie Shane

Electronic Theses and Dissertations

The control of vector-borne diseases such as malaria has been an extremely important research subject for hundreds of years. Because of the complex lifecycles of the pathogens that cause these diseases, finding a comprehensive treatment or preventative strategy has proven extremely difficult. Malaria alone is responsible for almost half a million deaths annually, most of them children under 5 years old. This disease is caused by parasitic protists in the genus Plasmodium that are transmitted to humans from Anopheles sp. mosquitoes. Most preventative strategies that are in use today revolve around controlling the vectors, including bed nets, insecticides, and larval …

Associations Between Avian Spruce-Fir Species, Harvest Treatments, Vegetation, And Edges, Brian W. Rolek

Electronic Theses and Dissertations

Habitat loss is the primary cause of species loss and declines of global biodiversity. Several birds associated with the spruce-fir forest type (hereafter spruce-fir birds) have declining populations across the continent in the Atlantic Northern Forest, and the extent of coniferous forest has declined in some areas. This region is extensively and intensively managed for timber products.

To investigate the influence from harvest treatments on the spruce-fir bird assemblage during the breeding and post-breeding period in lowland conifer and mixed-wood forests, we used avian point count detection data to test for associations between avian assemblages and seven common harvest treatments. …

Regulation Of In Vivo Excitatory/Inhibitory Balance By The Cystine/Glutamate Exchanger System Xc-, Sheila Marie Shahidzadeh Sears

Dissertations - ALL

System xc- (Sxc-) is a cellular antiporter that links the import of L-cystine with the export of L-glutamate. In the central nervous system (CNS), this export contributes to the ambient glutamate levels found in the synaptic cleft. To wit, a 50% reduction in extracellular glutamate has been demonstrated in animals null for the substrate-specific light chain, xCT. Moreover, in most tissues, including the CNS, cystine import through Sxc- is necessary for the synthesis and maintenance of glutathione (GSH) levels. Given that either a reduction in ambient glutamate levels and/or a redox imbalance involving GSH have been reported to affect synaptic …

Identifying The Genetic Mechanisms In Seizure Threshold Regulation, Yifan Gong

Dissertations - ALL

Epilepsy is a brain disease defined by having recurrent and spontaneous seizures. The susceptibility to seizure is determined by seizure threshold, which describes the balance between excitatory and inhibitory neurotransmission in the brain. Epileptogenesis, the transition from normal brain to epileptic brain, is accompanied by a progressive reduction of seizure threshold and has been shown to have genetic influences. Expression of neuronal cyclooxygenase-2 (COX-2) gene, PTGS2, a primary gene that regulates prostaglandin synthesis in the normal brain, is enhanced by excitatory neurotransmission and is under tight regulation of N-Methyl-D-Aspartate type glutamate receptor (NMDAR) activity in cortical neurons. The 3’ untranslated …

Comparative Ecophysiology Of Native And Invasive Plants Across Populations, Species, And Continents, Kelsey Anne Martinez

Dissertations - ALL

Invasive species are a persistent threat to biodiversity and agriculture that cost countries millions of dollars each year. Despite the scale and impact of the problem of invasive species, it remains a mystery why some introduced species become invasive and others remain benign. Here, I examined the theory that invasive species possess key traits which make them successful invaders. Specifically, I investigated the hypotheses that 1) plasticity increases invasive species’ success compared to native species, 2) invaders evolve rapidly in their new ranges, 3) invasive species avoid tradeoffs apparent in natives related to growth, resource use, or defense. Using 30 …

Survival In The Forest Understory: Resilience And Resistance To Damage In Native And Invasive Woody Plants, Elise Hinman

Dissertations - ALL

Non-native woody plants from Europe and East Asia have invaded intact, low-light forest understories in Eastern North America. Compared to co-occurring native species, invasive species exhibit greater productivity and resource use efficiency, but the extent to which plants are subject to tradeoffs between productivity and survival is unknown. Herbivory and freezing events are common sources of damage in the forest understory, and non-structural carbohydrates (NSCs) and defense compounds support resilience and resistance to damage. In this dissertation, I evaluated the hypothesis that invasive species maintain high productivity at the expense of storage and defense, reducing their survival under severe damage. …

Ecological Consequences Of Personality In A Guild Of Terrestrial Small Mammals: From Trappability To Seed Dispersal, Allison M. Brehm

Electronic Theses and Dissertations

Individual animals exhibit consistent behavioral tendencies over time and across contexts that have been termed personalities. Personality encapsulates an individual’s unique way of behaving and responding to life’s challenges, and since individuals vary in both personality type and their ability to exhibit behavioural plasticity, there are important links between an individual’s personality and its response to a changing environment; resulting in the study of animal personalities becoming increasingly popular in recent years. Previous research suggests that personality traits measured through standardized behavioural tests predict trappability (i.e. ‘trap happiness’ versus ‘trap shyness’). This relationship has been explored only within single …

A Change In Grain? Diet Induced Plasticity In The Generalist Grasshopper Melanoplus Differentialis, Austin M. Culotta

University of New Orleans Theses and Dissertations

Phenotypic plasticity is favored in heterogeneous environments in which alternative phenotypes can exploit alternative resources. However, it’s not clear whether phenotypic plasticity is useful in environments that become more homogenous over an organism’s life cycle. I studied a population of grasshopper Melanoplus differentialis that experiences high resource diversity as nymphs but low resource diversity as adults to determine if individuals can undergo diet-induced morphological plasticity in head shape to increase biting ability and ingestion of hard diets. Insects on a soft diet were larger and had greater bite force than those on a hard diet. Head structures related to chewing …

Legacy Habitat Suitability Of Eastern Oysters (Crassostrea Virginica) In Louisiana: A Prelude To Mississippi River Delta Freshwater Diversions, Tasia Mv Denapolis

University of New Orleans Theses and Dissertations

The Louisiana oyster industry is greatly impacted by freshwater and sediment diversions that are part of the effort to restore the state’s coastline. A habitat suitability index (HSI) proposes species-habitat relationships that can be instrumental in creating impact assessments and suitability predictions for management as new diversions are implemented. An oyster (Crassostrea virginica) HSI was developed using three variables crucial to oyster sustainability: average annual salinity, minimum monthly salinity, and average salinity during the spawning season. These Legacy HSI visualizations show annual fluctuations in the distribution of zones suitable for oyster cultivation prior to proposed diversions in Pontchartrain …