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A Mathematical Model Of Tau Protein Hyperphosphorylation: The Effects Of Kinase Inhibitors As A Theoretical Alzheimer's Disease Therapy, Patrick Neil Blank Jan 2015

A Mathematical Model Of Tau Protein Hyperphosphorylation: The Effects Of Kinase Inhibitors As A Theoretical Alzheimer's Disease Therapy, Patrick Neil Blank

Dissertations, Theses, and Masters Projects

No abstract provided.


Investigation Of Microwave Technologies For Biochemical Applications, Valerie Terynn Tripp Jan 2013

Investigation Of Microwave Technologies For Biochemical Applications, Valerie Terynn Tripp

Dissertations, Theses, and Masters Projects

No abstract provided.


Thermochemistry Of Amino Acids And Constrained Diamines, Erica Jane Tullo Jan 2012

Thermochemistry Of Amino Acids And Constrained Diamines, Erica Jane Tullo

Dissertations, Theses, and Masters Projects

The gas-phase proton affinities of several highly basic amino acids and diamines were determined using the extended kinetic method in an ESI-quadrupole ion trap instrument. The non-protein amino acid L-canavanine is structurally related to L-arginine with an oxygen substituted for the terminal methylene group of L-arginine and is highly toxic to humans. The proton affinity of L-arginine, a protein amino acid, was determined to be 1036 kJ mol -1, whereas the proton affinity of L-canavanine was determined to be 1005 kJ mol-1. Thus, substitution of an oxyguanidino group for the guanidine group in L-arginine results in a large decrease in ...


Hydrogen/Deuterium Exchange Studies Of Protein And Non-Protein Amino Acids Using Electrospray Ionization Mass Spectrometry, Justine Victoria Arrington Jan 2012

Hydrogen/Deuterium Exchange Studies Of Protein And Non-Protein Amino Acids Using Electrospray Ionization Mass Spectrometry, Justine Victoria Arrington

Dissertations, Theses, and Masters Projects

No abstract provided.


Reactive Sulfur: Redox Reactions Of Cysteines And Methionines In The Cytoskeletal Protein Tubulin, Tara Dawn Hagedorn Jan 2011

Reactive Sulfur: Redox Reactions Of Cysteines And Methionines In The Cytoskeletal Protein Tubulin, Tara Dawn Hagedorn

Dissertations, Theses, and Masters Projects

No abstract provided.


Investigations Of The Fragmentation Spectra Of Dipeptides Containing Lysine And Its Non-Protein Amino Acid Homologs, Omar Hamdy Jan 2011

Investigations Of The Fragmentation Spectra Of Dipeptides Containing Lysine And Its Non-Protein Amino Acid Homologs, Omar Hamdy

Dissertations, Theses, and Masters Projects

No abstract provided.


Computational And Experimental Investigations Of Gas-Phase Thermodynamics Of Non-Protein Amino Acids, Ashley R. Janiga Jan 2010

Computational And Experimental Investigations Of Gas-Phase Thermodynamics Of Non-Protein Amino Acids, Ashley R. Janiga

Dissertations, Theses, and Masters Projects

No abstract provided.


The Role Of Copepods And Heterotrophic Dinoflagellates In The Production Of Dissolved Organic Matter And Inorganic Nutrients, Grace Kathleen Saba Jan 2010

The Role Of Copepods And Heterotrophic Dinoflagellates In The Production Of Dissolved Organic Matter And Inorganic Nutrients, Grace Kathleen Saba

Dissertations, Theses, and Masters Projects

Zooplankton play a key role in the cycling of dissolved organic matter (DOM) and inorganic nutrients. The factors that affect these processes, however, are not fully understood. I measured the effects of various diets on DOM and inorganic nutrient production by the copepod Acartia tonsa and the heterotrophic dinoflagellate Oxyrrhis marina, and explored the mechanisms of nutrient release from copepods. Copepods feeding on a mixed diet, the preferred diet of most copepods, had significantly lower dissolved organic carbon (DOC), ammonium (NH4+), and total dissolved nitrogen (TDN) release rates compared to feeding on a carnivorous or herbivorous diet. Thus, copepod feeding ...


Identification And Quantification Of Polycyclic Musks And Methyl-Triclosan In Unknown Freshwater Fish Tissue Samples, Elizabeth Mara Jacobs Jan 2009

Identification And Quantification Of Polycyclic Musks And Methyl-Triclosan In Unknown Freshwater Fish Tissue Samples, Elizabeth Mara Jacobs

Dissertations, Theses, and Masters Projects

No abstract provided.


Stable Isotope Dynamics In Summer Flounder Tissues, With Application To Dietary Assessments In Chesapeake Bay, Andre Buchheister Jan 2008

Stable Isotope Dynamics In Summer Flounder Tissues, With Application To Dietary Assessments In Chesapeake Bay, Andre Buchheister

Dissertations, Theses, and Masters Projects

Stable isotope techniques were applied to summer flounder, Paralichthys dentatus, in Chesapeake Bay to elucidate the relative importance of different prey groups on the growth and productivity of this species. Prior to field application, a laboratory diet-shift study was conducted to evaluate methodological assumptions and obtain necessary isotopic parameters. Specifically, the goals of the laboratory study were to 1) determine isotopic turnover rates and fractionations of δ13C and δ15N in liver, whole blood, and white muscle and 2) estimate the relative importance of growth and metabolic processes on isotopic turnover. Groups of captive juvenile summer flounder (130-255mm total length) were ...


Cloning And Functional Characterization Of Hypoxia-Inducible Factor 1alpha Upstream Regions In Xenopus Laevis, Conor W. Sipe Jan 2003

Cloning And Functional Characterization Of Hypoxia-Inducible Factor 1alpha Upstream Regions In Xenopus Laevis, Conor W. Sipe

Dissertations, Theses, and Masters Projects

No abstract provided.


Evolution And Analysis Of A Catalytically Effective Model Enzyme: The Importance Of Active Site Orientation And Tuned Conformational Fluctuations, G. S. Blair Williams Jan 2003

Evolution And Analysis Of A Catalytically Effective Model Enzyme: The Importance Of Active Site Orientation And Tuned Conformational Fluctuations, G. S. Blair Williams

Dissertations, Theses, and Masters Projects

No abstract provided.


A Dynamical Perspective On Enzymatic Catalysis, Shiying Shang Jan 2002

A Dynamical Perspective On Enzymatic Catalysis, Shiying Shang

Dissertations, Theses, and Masters Projects

No abstract provided.


Environmental Stress In Hard Coral: Evaluating Lipid As An Indicator Of Sublethal Stress On Short Time Scales, David Harold Niebuhr Jan 1999

Environmental Stress In Hard Coral: Evaluating Lipid As An Indicator Of Sublethal Stress On Short Time Scales, David Harold Niebuhr

Dissertations, Theses, and Masters Projects

Lipid quality was evaluated in Montastrea spp. under sediment- and heat-stressed conditions to evaluate lipid ratio as an indicator of sub-lethal stress on short time scales. The ratio of storage lipid (wax ester + triacylglyceride) to structural lipid (sterol esters + phospholipid) decreased significantly (0.25 to 0.14, p < 0.01) after experimental sedimentation. FAME analysis of colonies exposed to experimental sedimentation showed a reduction of the algal, 18:3(n-6) and 18:4(n-3), polyunsaturated fatty acid (PUFA) in the polar lipid fraction. This loss of PUFA suggests a loss of algal membrane in sediment-stressed colonies. Lipid quality was similarly measured in M. faveolata over a 10-day period. Mean (n = 20) ratio of storage to structural lipid in M. faveolata dropped from 2.43 to a level of 0.98 immediately following a natural sedimentation event before recovering to levels of 1.4 and 2.9 on post-storm days 2 and 4, respectively. Colonies of M. annularis subject to heat-stress (35??C) exhibited no significant change in storage lipid ratio, while levels of Free Fatty Acids increased significantly from 0.012 (n = 22) to 0.156 mg lipid/g dry tissue (n = 22)(p < 0.05). FAME analysis of tissue lipids extracted from the heat-stressed colonies showed changes in the polar fraction, with significant decreases in the 18:3(n-6), 18:3(n-3), 18:4(n-3), 20:4(n-6) and 20:5(n-3) (p < 0.05) PUFA and subsequent significant increases in the saturated fatty acids, 16:0 and 18:0 (p < 0.05). These changes in lipid quantity and quality indicate possible oxidation and preferential digestion of zooxanthellar membranes. Stress experiments were repeated in M. annularis using VacutainerRTM blood collection tubes to collect micro-tissue samples without destroying skeleton of the sample colonies. A significant decrease in storage: structural lipid ratio after sedimentation was also detected using the micro-tissue technique. This study indicates that the relative abundance of lipid subclass components can indicate sub-lethal environmental stress, on short time scales, in M. annularis and M. faveolata. Furthermore, micro-tissue collection techniques permit repeated monitoring coral colonies to assess the manifestation of stress from first detection of impact at the cellular level to changes in community to changes in community structure detectable over longer time scales.


Determination Of Trace Levels Of Lead In Whole Blood By Graphite Furnace Atomic Absorption Spectroscopy, Leslie A. Sombers Jan 1998

Determination Of Trace Levels Of Lead In Whole Blood By Graphite Furnace Atomic Absorption Spectroscopy, Leslie A. Sombers

Dissertations, Theses, and Masters Projects

No abstract provided.


Perkinsus Marinus Extracellular Proteases: Modulation Of Production By Environmental Factors And Effects On The Host Defense Parameters Of The Eastern Oyster Crassostrea Virginica, Kathleen A. Garreis Jan 1996

Perkinsus Marinus Extracellular Proteases: Modulation Of Production By Environmental Factors And Effects On The Host Defense Parameters Of The Eastern Oyster Crassostrea Virginica, Kathleen A. Garreis

Dissertations, Theses, and Masters Projects

No abstract provided.


Nutrition And Feeding In Striped Bass Morone Saxatilis Larvae: Lipid And Fatty Acid Requirements And Microencapsulated Diets, Sureyya Ozkizilcik Jan 1995

Nutrition And Feeding In Striped Bass Morone Saxatilis Larvae: Lipid And Fatty Acid Requirements And Microencapsulated Diets, Sureyya Ozkizilcik

Dissertations, Theses, and Masters Projects

There has been a growing interest in the commercial aquaculture of striped bass, Morone saxatilis. Little is known, however, about the nutritional requirements and feeding physiology of striped bass larvae. The objectives of this study were (a) to evaluate the efficiency of the live food enrichment techniques in studying the nutritional requirements for polyunsaturated fatty acids (PUFA), phospholipids and free amino acids, (b) to determine the ontogenetic changes of lipolytic enzymes, and (c) to develop a microencapsulated diet for striped bass larvae as full or partial replacement of live food. Three enrichment techniques, namely, microencapsulated fish oil, yeast/fish oil ...


Uptake Routes Of Benzo[A]Pyrene In An Estuarine Killifish: Cytochrome P4501a Immunohistochemistry Using Whole Fish, Maria Karin Cochran Jan 1994

Uptake Routes Of Benzo[A]Pyrene In An Estuarine Killifish: Cytochrome P4501a Immunohistochemistry Using Whole Fish, Maria Karin Cochran

Dissertations, Theses, and Masters Projects

No abstract provided.


Stripping And Reassembly Of The Yeast Vacuolar H+-Atpase Peripheral Protein Subunits, Heather R. Yarashus Jan 1993

Stripping And Reassembly Of The Yeast Vacuolar H+-Atpase Peripheral Protein Subunits, Heather R. Yarashus

Dissertations, Theses, and Masters Projects

No abstract provided.


Evaluation Of A Technique To Quantify Lipids In Bivalve Larvae Crassostrea Virginica Gmelin, Using Nile Red And Epiflourescence Microscopy, Laura Liliana Castell Perez Jan 1991

Evaluation Of A Technique To Quantify Lipids In Bivalve Larvae Crassostrea Virginica Gmelin, Using Nile Red And Epiflourescence Microscopy, Laura Liliana Castell Perez

Dissertations, Theses, and Masters Projects

No abstract provided.


Monooxygenase Induction And Lethality As Endpoints In Aquatic Toxicology, Daniel W. Sved Jan 1991

Monooxygenase Induction And Lethality As Endpoints In Aquatic Toxicology, Daniel W. Sved

Dissertations, Theses, and Masters Projects

Spot, Leiostomus xanthurus, were exposed to suspended sediments (&\approx&20 mg/L) contaminated with polycyclic aromatic hydrocarbons (PAH) in a laboratory flow-through system to evaluate the applicability of hepatic ethoxyresorufin O-deethylase (EROD) induction as an indicator of PAH exposure. PAH sources tested were coal-tar creosote (CTC), a low molecular weight fraction of creosote (LMWF), and a high molecular weight fraction of creosote (HMWF). A standard 96-h acute toxicity test was conducted to ensure that PAH concentrations tested in induction studies were sub-acutely toxic. The 96-h LC50 for spot was 1740 &\mu&g PAH/L (95% confidence interval = 1480-2060 &\mu&g PAH/L). The lowest concentration producing an observable effect in 96 h was 560 &\mu&g PAH/L; no effects were observed for spot exposed to 250 &\mu&g PAH/L for 96 h. Induction of hepatic EROD activity occurred rapidly in fish exposed to high environmentally realistic concentrations of CTC or the HMWF, but not the LMWF. Maximal induction (30-fold) occurred in fish exposed for 48 h to 150 &\mu&g PAH/L. Induction was concentration-dependent up to 150 &\mu&g PAH/L; at 320 &\mu&g PAH/L induction was 14-fold. EROD activity decreased upon further exposure; by day 7, EROD activity was not significantly different than that on day 0. EROD activity in fish exposed to 16 &\mu&g PAH/L was not consistently higher than that in control fish. Spot exposed to at least 70 &\mu&g PAH/L from CTC or the HMWF experienced severe fin erosion, epidermal lesions, and mortality beginning a few days after maximal EROD induction occurred. No relationship between EROD induction and whole animal responses is implied, only that EROD induction ...


Immunological Identification Of A Centrin Homologue In The Red Alga Gracilaria Tikvahiae, Christopher Lee Dassler Jan 1991

Immunological Identification Of A Centrin Homologue In The Red Alga Gracilaria Tikvahiae, Christopher Lee Dassler

Dissertations, Theses, and Masters Projects

No abstract provided.


Effects Of Selected Nitrogen-Containing Aromatic Compounds (Ncacs) On Physiological Properties In Escherichia Coli, W. James Catallo Iii Jan 1989

Effects Of Selected Nitrogen-Containing Aromatic Compounds (Ncacs) On Physiological Properties In Escherichia Coli, W. James Catallo Iii

Dissertations, Theses, and Masters Projects

This research examined the effects of quinoline and 4-azafluorene on respiratory electron transport rate (ET), outer membrane permeability and topology, oxygen consumption, and viable cell density in Escherichia coli cell suspensions. ET was estimated spectrophotometrically using INT (2-(p-iodophenyl)-3-(p-nitrophenyl)-5-(phenyl)-2H-tetrazolium chloride, which is reduced in vivo to a red colored formazan (INTF). Both test compounds caused anomalous dose-response behavior in INT assays: in a defined window of doses, ET rates near or above the controls were observed. These doses showed altered INT reduction kinetics, decreased cellular oxygen demand, and decreased viable cell densities. Experiments with E ...


Structure And Function Of Crustacean Hemocyaninis, John Edwin Reese Jan 1989

Structure And Function Of Crustacean Hemocyaninis, John Edwin Reese

Dissertations, Theses, and Masters Projects

No abstract provided.


Anion And Urea Sensitivity Of Three Elasmobranch Hemoglobins, David Allen Scholnick Jan 1989

Anion And Urea Sensitivity Of Three Elasmobranch Hemoglobins, David Allen Scholnick

Dissertations, Theses, and Masters Projects

No abstract provided.


Distribution Of The Heterogeneous Hemocyanin Subunits Of Callinestes Sapidus (Rathbun) Along A Salinity Gradient, Julie Sayre Rainer Jan 1989

Distribution Of The Heterogeneous Hemocyanin Subunits Of Callinestes Sapidus (Rathbun) Along A Salinity Gradient, Julie Sayre Rainer

Dissertations, Theses, and Masters Projects

No abstract provided.


Localization Of A Camp-Dependent Protein Kinase In Ovarian Mitochondria, William Jameson Roberts Jan 1986

Localization Of A Camp-Dependent Protein Kinase In Ovarian Mitochondria, William Jameson Roberts

Dissertations, Theses, and Masters Projects

No abstract provided.


Synthesis And Characterization Of Some Oxoperoxopolycarboxylato Vanadates (V) And Their Biochemical Significance, Myunghi Lee Jan 1984

Synthesis And Characterization Of Some Oxoperoxopolycarboxylato Vanadates (V) And Their Biochemical Significance, Myunghi Lee

Dissertations, Theses, and Masters Projects

No abstract provided.


Anaerobic Metabolism Of The Ribbed Mussel, Geukensia Demissa, Ming-Shan Ho Jan 1980

Anaerobic Metabolism Of The Ribbed Mussel, Geukensia Demissa, Ming-Shan Ho

Dissertations, Theses, and Masters Projects

The anaerobic metabolism of the intertidal ribbed mussel, Geukensia demissa (= Modiolus demissus), is reported in this dissertation. This mollusc was selected because anaerobic metabolism is believed to be of vital significance to its survival during the air exposure period of the tidal cycle.;Ribbed mussels, Geukensia demissa, were maintained in either aerated or hypoxic water for up to four days. Major metabolites and polysaccharide of each mussel were then analyzed and compared. Succinate, propionate and alanine were found to accumulate hypoxically, but not malate, (alpha)-keto-glutarate and pyruvate. The polysaccharide content of each mussel was quite different and did not ...


An Investigation Of Possible Inhibitors For D-Amino Acid Oxidase, Sue Ellen Delos Jan 1979

An Investigation Of Possible Inhibitors For D-Amino Acid Oxidase, Sue Ellen Delos

Dissertations, Theses, and Masters Projects

No abstract provided.