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Full-Text Articles in Physical Sciences and Mathematics
Spread And Interaction Of Epidemics And Information On Adaptive Social Networks, Yunhan Long
Spread And Interaction Of Epidemics And Information On Adaptive Social Networks, Yunhan Long
Dissertations, Theses, and Masters Projects
The spread of diseases and opinions has profoundly affected the development of human societies. The structure of the underlying social network may change as a result of individuals changing their social connections in response to an ongoing epidemic or opinion spreading, either for self protection or as an expression of personal values. The interaction of spreading processes and the underlying network structure has been a focus of many recent studies. In this dissertation, we construct models to better incorporate heterogeneous responses to disease spread and attempted opinion spread.;We first model the simultaneous spread of an epidemic and awareness about the …
A Mathematical Model Of Tau Protein Hyperphosphorylation: The Effects Of Kinase Inhibitors As A Theoretical Alzheimer's Disease Therapy, Patrick Neil Blank
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.
Automated Reductions Of Markov Chain Models Of Calcium Release Site Models, Yan Hao
Automated Reductions Of Markov Chain Models Of Calcium Release Site Models, Yan Hao
Dissertations, Theses, and Masters Projects
Markov chain models have played an important role in understanding the relationship between single channel gating of intracellular calcium (Ca2+) channels, specifically 1,4,5-trisphosphate receptors (IP3Rs) and ryanodine receptors (RyRs), and the stochastic dynamics of Ca2+ release events, known as Ca2+ puffs and sparks. Mechanistic Ca2+ release site models are defined by the composition of single channel models whose transition probabilities depend on the local calcium concentration and thus the state of the other channels. Unfortunately, the large state space of such compositional models impedes simulation and computational analysis of the whole cell Ca2+ signaling in which the stochastic dynamics of …
Thermochemistry Of Amino Acids And Constrained Diamines, Erica Jane Tullo
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 …
Molecular Marker Development For The Discrimination Of Atlantic And Pacific Blue Marlin (Makaira Nigricans), Laurie Sorenson
Molecular Marker Development For The Discrimination Of Atlantic And Pacific Blue Marlin (Makaira Nigricans), Laurie Sorenson
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
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
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.
Assessing Genetic Variation Within And Among Native Populations And Hatchery Stocks Of Crassostrea Ariakensis Using Microsatellite Markers, Jie Xiao
Dissertations, Theses, and Masters Projects
Assessing genetic variation within and among native populations and hatchery stocks of Crassostrea ariakensis using microsatellite markers In response to the dramatic decline of eastern oyster (Crassostrea virginica) populations in the Chesapeake Bay, introduction of the non-native Asian oyster Crassostrea ariakensis has been proposed. Currently several hatchery stocks of C. ariakensis, derived from a few wild populations along the coast of Japan and China, are being maintained in U.S. hatcheries in the Pacific northwest and on the east coast. In recent years, as the risks of the proposed introduction are being assessed, these hatchery animals have been widely used for …
A Molecular Analysis Of Atlantic Menhaden (Brevoortia Tyrannus) Stock Structure, Abigail J. Lynch
A Molecular Analysis Of Atlantic Menhaden (Brevoortia Tyrannus) Stock Structure, Abigail J. Lynch
Dissertations, Theses, and Masters Projects
Atlantic menhaden is an ecologically and economically important species along the U.S. east coast. As a filter-feeder and key prey fish, it provides a critical link between primary production, phytoplankton, and larger piscivorous predators, such as striped bass, bluefish, and weakfish. The species is also the target of one of the largest commercial fisheries in the country. Menhaden are assessed as a single, coastwide stock, and recent assessments indicate that it is not overfished. However, there is very limited population genetics data to support the assumption of a single stock. Additionally, the recent consolidation of the fishery and localization of …
Novel Use Of A Natural Isotope Signature To Track Recruitment And Evaluate Age Determination Methods For The 2002 Year Class Of American Shad In The York River, Sally A. Upton
Dissertations, Theses, and Masters Projects
No abstract provided.
Effects Of Molecular Motion On Deuteron Magic Angle Spinning Nmr Spectra, Yuanyuan Huang
Effects Of Molecular Motion On Deuteron Magic Angle Spinning Nmr Spectra, Yuanyuan Huang
Dissertations, Theses, and Masters Projects
Solid state deuteron NMR experiments, especially magic angle spinning (MAS) and off-magic angle spinning (OMAS), are developed to explore dynamical systems. A theoretical discussion of interactions relevant for spin-1 nuclei is presented. Practical aspects of MAS/OMAS experiments are described an detail. The dominant quadrupolar coupling interaction in deuteron NMR has been simulated and the effects of multiple-frame molecular motions on MAS/OMAS spectra are taken into account in this calculation. Effects of chemical shift anisotropy are also simulated, and shown to be small under conditions of rapid sample spinning.;Two numerical methods, direct integration and an efficient simulation routine based on Floquet …
A Molecular Technique For Specific Identification Of Western Atlantic Ocean Scombrids And An Analysis Of A Larval Scombrid Assemblage Off The Kona Coast Of Hawaii, Melissa A. Paine
A Molecular Technique For Specific Identification Of Western Atlantic Ocean Scombrids And An Analysis Of A Larval Scombrid Assemblage Off The Kona Coast Of Hawaii, Melissa A. Paine
Dissertations, Theses, and Masters Projects
No abstract provided.
A Mycobacterium-Inducible Nramp In Striped Bass Morone Saxatilis, Erin Jeffrey Burge
A Mycobacterium-Inducible Nramp In Striped Bass Morone Saxatilis, Erin Jeffrey Burge
Dissertations, Theses, and Masters Projects
In mammals, the natural resistance-associated macrophage protein 1 gene, Nramp1, plays a major role in resistance to mycobacterial infections. Chesapeake Bay (USA) striped bass, Morone saxatilis, are currently experiencing an epizootic of mycobacteriosis that threatens the health of this ecologically and economically important species. This dissertation characterizes an Nramp gene in this species (MsNramp ) and provide evidence for induction following Mycobacterium exposure. The striped bass MsNramp gene and 554 amino acid sequence contain all the signal features of the Nramp family, including a topology of 12 transmembrane domains (TM), the transport protein specific 'binding-protein-dependent transport system inner membrane component …
Genetic Variation Within And Among The Suminoe Oyster (Crassostrea Ariakensis) Populations And Stocks As Assessed By Molecular Markers, Qian Zhang
Dissertations, Theses, and Masters Projects
No abstract provided.
Genetic Stock Structure Of The Sailfish, Istiophorus Platypterus, Based On Nuclear And Mitochondrial Dna, Jan Renee Mcdowell
Genetic Stock Structure Of The Sailfish, Istiophorus Platypterus, Based On Nuclear And Mitochondrial Dna, Jan Renee Mcdowell
Dissertations, Theses, and Masters Projects
The results of life history studies involving the sailfish, Istiophorus platypterus, from the Atlantic, Pacific, and Indian oceans were reviewed. Results of studies agree on several aspects of sailfish biology; sailfish exhibit opportunistic feeding behavior, follow the 28??C isotherm, spawn in summer mature at approximately age 3, and are the least migratory of the billfishes. However, results are in conflict concerning sex ratio and whether sailfish are single or multiple spawners. Although many researchers have reported that sailfish are sexually dimorphic, their fragile otoliths make them difficult to age, aging studies have not been validated, and sexual dimorphism has not …
Molecular Characterization Of Cultured Perkinsus Marinus Isolates, Gwynne D. Brown
Molecular Characterization Of Cultured Perkinsus Marinus Isolates, Gwynne D. Brown
Dissertations, Theses, and Masters Projects
Perkinsus marinus is the causative agent of the oyster disease Dermo in the eastern oyster, Crassostrea virginica. In vitro propagation of the parasite has led to the establishment of multiple isolates by several investigators. Little work, however, has been done to characterize different isolates. In this study multiple isolates were examined for genetic and biochemical diversity. at two loci, the ITS region and the ATAN region, there was as much intra-isolate genetic variation among DNA sequences of some isolates as there was inter-isolate variation. Variation was also observed at a third loci, a subtilisin-like serine protease gene. This is the …
Environmental Stress In Hard Coral: Evaluating Lipid As An Indicator Of Sublethal Stress On Short Time Scales, David Harold Niebuhr
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.
Functional And Molecular Analysis Of Antibody Affinity Maturation In Rainbow Trout (Oncorhynchus Mykiss), Haili Zhang
Functional And Molecular Analysis Of Antibody Affinity Maturation In Rainbow Trout (Oncorhynchus Mykiss), Haili Zhang
Dissertations, Theses, and Masters Projects
No abstract provided.
Indo-Pacific Population Structure Of The Black Marlin, Makaira Indica, Inferred From Molecular Markers, Brett Falterman
Indo-Pacific Population Structure Of The Black Marlin, Makaira Indica, Inferred From Molecular Markers, Brett Falterman
Dissertations, Theses, and Masters Projects
No abstract provided.
Molecular Phylogeny Of Lake Baikal Amphipods, Kenneth S. Macdonald
Molecular Phylogeny Of Lake Baikal Amphipods, Kenneth S. Macdonald
Dissertations, Theses, and Masters Projects
No abstract provided.
Comparative Evolution Of Molecular Markers: An Analysis Of Genetic Variation Within The Blue Marlin (Makaira Nigricans), Vincent Patrick Buonaccorsi
Comparative Evolution Of Molecular Markers: An Analysis Of Genetic Variation Within The Blue Marlin (Makaira Nigricans), Vincent Patrick Buonaccorsi
Dissertations, Theses, and Masters Projects
Blue marlin diversity was assessed at mtDNA, scnDNA, microsatellite DNA, and allozyme molecular markers. Hierarchical analysis of molecular variance (AMOVA) revealed that most genetic variation was maintained within populations, with a non-significant fraction attributable to variation among temporal replicates and between locations within oceans. In contrast, inter-ocean divergence was highly significant for a majority of loci within each marker class. Previous studies of mitochondrial DNA (mtDNA; n = 104) genetic variation within the blue marlin revealed two distinct clades of haplotypes, one of which was present only in the Atlantic (the 'Atlantic clade'), at a frequency of 40% &(F\sb{lcub}st{rcub}& = …
Determination Of Trace Levels Of Lead In Whole Blood By Graphite Furnace Atomic Absorption Spectroscopy, Leslie A. Sombers
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
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.
Expression Of The Xenobiotic Transporter P-Glycoprotein In The Mummichog (Fundulus Heteroclitus), Peter S. Cooper
Expression Of The Xenobiotic Transporter P-Glycoprotein In The Mummichog (Fundulus Heteroclitus), Peter S. Cooper
Dissertations, Theses, and Masters Projects
The mammalian mdr1 P-glycoprotein (Pgp) has been implicated in xenobiotic resistance of drug-resistant cell lines and tumors, and may function in excretion or exclusion of toxic xenobiotics at several sites within the body. Pgp gene family members are expressed in excretory epithelia of several aquatic taxa and may contribute to the survival of pollution-tolerant aquatic animals in contaminated environments. For this reason the expression of Pgp family members was investigated in the livers and liver tumors of creosote-resistant mummichog (Fundulus heteroclitus) inhabiting a creosote-contaminated site (Atlantic Wood) in the Elizabeth River, Virginia. Expression of members of the Pgp gene family …
Nutrition And Feeding In Striped Bass Morone Saxatilis Larvae: Lipid And Fatty Acid Requirements And Microencapsulated Diets, Sureyya Ozkizilcik
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 emulsion …
Global Phylogeography Of Yellowfin Tuna, Thunnus Albacares, And Mackerels Of The Genus Scomber, Daniel R. Scoles
Global Phylogeography Of Yellowfin Tuna, Thunnus Albacares, And Mackerels Of The Genus Scomber, Daniel R. Scoles
Dissertations, Theses, and Masters Projects
Intraspecific genetic relationships within yellowfin tuna, Thunnus albacares, and three mackerels of the genus Scomber were studied by restriction fragment length polymorphism (RFLP) analysis of mitochondrial DNA (mtDNA). The comparison of these scombrids, with different larval distributions, adult distributions, and vagilities, served to investigate the hypothesis that population structure in marine fishes results from geographic and physical oceanographic processes that limit dispersal of early life history stages. Samples of 20 yellowfin tuna were examined from each of five Pacific locations and one Atlantic location. MtDNA analysis with 12 informative restriction endonucleases demonstrated considerable genetic variation, as evidenced by overall nucleon …
Mitochondrial Dna Variation In Natural And Cultured Populations Of The Bay Scallop, Argopecten Irradians (Lamarck) And The Calico Scallop, Argopecten Gibbus (Dall), Sandra Grace Blake
Mitochondrial Dna Variation In Natural And Cultured Populations Of The Bay Scallop, Argopecten Irradians (Lamarck) And The Calico Scallop, Argopecten Gibbus (Dall), Sandra Grace Blake
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
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
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 …
Mitochondrial Dna Variation In Striped Bass, Morone Saxatilis, From The Rappahannock River, Virginia, Carol Furman
Mitochondrial Dna Variation In Striped Bass, Morone Saxatilis, From The Rappahannock River, Virginia, Carol Furman
Dissertations, Theses, and Masters Projects
No abstract provided.