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Articles 1 - 21 of 21

Full-Text Articles in Life Sciences

Mercury Exposure In Terrestrial Insectivorous Birds, Scott Lawrence Friedman Jan 2007

Mercury Exposure In Terrestrial Insectivorous Birds, Scott Lawrence Friedman

Dissertations, Theses, and Masters Projects

No abstract provided.


A Molecular Study Of The Mitochondrial Genome And Invasions Of The Veined Rapa Whelk, Rapana Venosa, Emily A. Chandler Jan 2007

A Molecular Study Of The Mitochondrial Genome And Invasions Of The Veined Rapa Whelk, Rapana Venosa, Emily A. Chandler

Dissertations, Theses, and Masters Projects

No abstract provided.


Effects Of Regional Species Pool Dynamics On Metacommunity Structure And Ecosystem Function, Kristin E. France Jan 2007

Effects Of Regional Species Pool Dynamics On Metacommunity Structure And Ecosystem Function, Kristin E. France

Dissertations, Theses, and Masters Projects

Theory and small-scale experiments predict that biodiversity losses can decrease the magnitude and stability of ecosystem services such as production and nutrient cycling. Most of this research, however, has been isolated from spatial processes, such as dispersal and disturbance, which create and maintain diversity in nature. Since common anthropogenic drivers of biodiversity change, such as habitat fragmentation, species introductions, and climate change, are mediated by these understudied processes, it is unclear how environmental degradation will affect ecosystem services. This dissertation examines how diversity interacts with spatial processes to affect the magnitude and stability of ecosystem functions, using seagrass communities as ...


Characterization Of Exotic Pathogens Associated With The Suminoe Oyster, Crassostrea Ariakensis, Jessica A. Moss Jan 2007

Characterization Of Exotic Pathogens Associated With The Suminoe Oyster, Crassostrea Ariakensis, Jessica A. Moss

Dissertations, Theses, and Masters Projects

The eastern oyster, Crassostrea virginica, once an integral part of the ecology and economy of Chesapeake Bay, has been severely depleted. Factors leading to the decline of the eastern oyster include over-harvesting, environmental degradation and disease pressure caused by the protozoans Haplosporidium nelsoni and Perkinsus marinus, known commonly as MSX and Dermo, respectively. Studies regarding the feasibility of introducing a nonnative oyster to the Bay were initiated, and field-based research on an Asian oyster, Crassostrea ariakensis, suggested that it might be a viable species for introduction. Research surrounding the proposed introduction has focused on recommendations such as those from the ...


Bottom-Up And Climatic Forcing On The Nesting And Foraging Ecology Of Leatherback Turtles (Dermochelys Coriacea), Vincent Sellitto Saba Jan 2007

Bottom-Up And Climatic Forcing On The Nesting And Foraging Ecology Of Leatherback Turtles (Dermochelys Coriacea), Vincent Sellitto Saba

Dissertations, Theses, and Masters Projects

There currently exists a major dichotomy in the nesting population trends of leatherback turtles (Dermochelys coriacea) worldwide. Eastern Pacific populations have been declining precipitously while populations in the Atlantic and western Indian Oceans have been either stable or increasing. The populations in the western Pacific have also declined with some near extirpation. Factors attributed to the Pacific population decline are incidental fishery mortality and egg harvesting. Fishery mortality occurs throughout all basins, and with the exception of the western Pacific population, egg harvesting has not been a major factor at the major nesting complexes for almost two decades. Populations in ...


Phenotypic Properties And Intrinsic Currents Of Neurons Involved In The Neural Generation Of Mammalian Breathing, John A. Hayes Jan 2007

Phenotypic Properties And Intrinsic Currents Of Neurons Involved In The Neural Generation Of Mammalian Breathing, John A. Hayes

Dissertations, Theses, and Masters Projects

Breathing is essential for mammalian life. Although there is an emerging consensus that the inspiratory respiratory rhythm is generated in a lower brainstem region known as the preBotzinger Complex (preBotC), the mechanism of rhythmogenesis is still unclear. Additionally, the modulation of intrinsic currents within preBotC neurons has yet to be fully elucidated. This dissertation addresses both of these issues and relies on imaging, electrophysiological, and modeling techniques. The first chapter examines the size and composition of the preBotC. The chapter also decribes the means by which substance P (SP) excites the vast majority of preBotC neurons by illustrating the characteristics ...


Repeatability Of Mate Preferences And Mate-Choice Copying In Female Zebra Finches, Amanda Karen Houck Jan 2007

Repeatability Of Mate Preferences And Mate-Choice Copying In Female Zebra Finches, Amanda Karen Houck

Dissertations, Theses, and Masters Projects

No abstract provided.


The Effects Of Mercury On The Nesting Success And Return Rate Of Tree Swallows (Tachycineta Bicolor), Rebecka L. Brasso Jan 2007

The Effects Of Mercury On The Nesting Success And Return Rate Of Tree Swallows (Tachycineta Bicolor), Rebecka L. Brasso

Dissertations, Theses, and Masters Projects

No abstract provided.


Inactive Sulfide Mounds Of The Manus Basin: Invertebrate Composition And Potential For A Chemoautotrophic Food Web, Kristin Lynn Erickson Jan 2007

Inactive Sulfide Mounds Of The Manus Basin: Invertebrate Composition And Potential For A Chemoautotrophic Food Web, Kristin Lynn Erickson

Dissertations, Theses, and Masters Projects

No abstract provided.


Effects Of Mercury On Condition And Coloration Of Belted Kingfishers, Ariel Elizabeth White Jan 2007

Effects Of Mercury On Condition And Coloration Of Belted Kingfishers, Ariel Elizabeth White

Dissertations, Theses, and Masters Projects

No abstract provided.


The Infection Dynamics Of Pav1 In The Caribbean Spiny Lobster Panulirus Argus, Caiwen Li Jan 2007

The Infection Dynamics Of Pav1 In The Caribbean Spiny Lobster Panulirus Argus, Caiwen Li

Dissertations, Theses, and Masters Projects

Panulirus argus Virus 1 (PaV1) is an emerging disease in Caribbean spiny lobster Panulirus argus. It is considered a threat to the lobster industry in the Florida Keys. In order to understand the infection dynamics of the PaV1 virus in the lobster host, a sensitive and specific fluorescence in situ hybridization (FISH) assay was developed for diagnosis of PaV1 in lobsters. The lower limit of detection using the 110-bp DNA probe in a dot-blot hybridization for PaV1 was 10 pg of cloned DNA template and 10 ng of genomic DNA extracted from hemolymph of diseased spiny lobster. The probe specifically ...


Hypoxia And Macoma Balthica: Ecological Effects On A Key Infaunal Benthic Species, William Christopher Long Jan 2007

Hypoxia And Macoma Balthica: Ecological Effects On A Key Infaunal Benthic Species, William Christopher Long

Dissertations, Theses, and Masters Projects

Hypoxia, low dissolved oxygen, is an important environmental stressor in estuarine systems. In this dissertation, I examine the effects of hypoxia on the macrobenthic communities of the York and Rappahannock Rivers, Chesapeake Bay, USA, and in particular its effects on the infaunal clam Macoma balthica. A survey of the macrobenthic community was performed using box-coring before and after hypoxia in 2003 and 2004 in both rivers. Hypoxia was associated with a change in the macrobenthic community towards smaller, shorter-lived, opportunistic species; and a substantial decrease in biomass. M. balthica recruited into all areas of the river but suffered local extinction ...


Biogeochemistry And Phytoplankton Dynamics In The Ross Sea, Antarctica, Amy Rebecca Shields Jan 2007

Biogeochemistry And Phytoplankton Dynamics In The Ross Sea, Antarctica, Amy Rebecca Shields

Dissertations, Theses, and Masters Projects

The Ross Sea, Antarctica seasonal phytoplankton bloom is one of the largest in the Southern Ocean. This project focuses on the biological pump, which removes carbon from the surface ocean to the deep ocean through the settling of particulate organic matter, the advection of dissolved organic carbon, and active flux due to vertical migration of zooplankton. The objective of this study was to focus on three interrelated components of the biological pump including sedimentation, photosynthetic rates and grazing. The study was conducted in coordination with the Interannual Variability in the Antarctic-Ross Sea program, which covered the time period between 2001--2005 ...


Cortical Activity Mediating Motor Representations In Stroke Survivors, Matthew Warren Lowder Jan 2007

Cortical Activity Mediating Motor Representations In Stroke Survivors, Matthew Warren Lowder

Dissertations, Theses, and Masters Projects

No abstract provided.


Effects Of Molecular Motion On Deuteron Magic Angle Spinning Nmr Spectra, Yuanyuan Huang Jan 2007

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 ...


Patterns And Prevalence Of Metabolic Syndrome Among Persons Receiving Treatment With Antipsychotic Medications, Brittany Marie-Bach Harte Jan 2007

Patterns And Prevalence Of Metabolic Syndrome Among Persons Receiving Treatment With Antipsychotic Medications, Brittany Marie-Bach Harte

Dissertations, Theses, and Masters Projects

No abstract provided.


Feeding Ecology Of Atlantic Menhaden (Brevoortia Tyrannus) In Chesapeake Bay, Patrick D. Lynch Jan 2007

Feeding Ecology Of Atlantic Menhaden (Brevoortia Tyrannus) In Chesapeake Bay, Patrick D. Lynch

Dissertations, Theses, and Masters Projects

No abstract provided.


The Role Of Bacteria-Particle Interactions In Marine Snow Dynamics, Emily M. Yam Jan 2007

The Role Of Bacteria-Particle Interactions In Marine Snow Dynamics, Emily M. Yam

Dissertations, Theses, and Masters Projects

Marine snow aggregates are one of the primary vehicles for deep-sea carbon sequestration. Bacterial activity on marine snow affects both degradation and aggregation processes that determine the flux of carbon to depth, biogeochemical cycling, and microbial food webs. The microscale processes occurring on aggregates depend on specific interactions between bacteria and particles. In this thesis, I describe two such interactions which have larger scale implications on marine snow dynamics: (1) the effects of starvation on bacterial motility and colonization behaviors on marine aggregates and (2) interactions between bacteria and phytoplankton which could contribute to the production of TEP.

Current models ...


Trophic Ecology And Growth Dynamics Of Striped Bass (Morone Saxatilis) In Chesapeake Bay, With Reference To Mycobacteriosis, Kathleen Anne Mcnamee Jan 2007

Trophic Ecology And Growth Dynamics Of Striped Bass (Morone Saxatilis) In Chesapeake Bay, With Reference To Mycobacteriosis, Kathleen Anne Mcnamee

Dissertations, Theses, and Masters Projects

No abstract provided.


Biomarker Responses In Fathead Minnows (Pimephales Promelas) During Exposure To Exceptional Quality Biosolids, Constance A. Sullivan Jan 2007

Biomarker Responses In Fathead Minnows (Pimephales Promelas) During Exposure To Exceptional Quality Biosolids, Constance A. Sullivan

Dissertations, Theses, and Masters Projects

No abstract provided.


Monograph Of The North American Freshwater Fish Leeches (Oligochaeta: Hirudinida ; Piscicolidae) And Molecular Phylogeny Of The Family Piscicolidae, Julianne I. Williams Jan 2007

Monograph Of The North American Freshwater Fish Leeches (Oligochaeta: Hirudinida ; Piscicolidae) And Molecular Phylogeny Of The Family Piscicolidae, Julianne I. Williams

Dissertations, Theses, and Masters Projects

The phylogeny of the Piscicolidae was analyzed from combined sequence data of 18S rDNA, cytochrome c oxidase subunit I (CO-I), nicotinamide adenine dinucleotide dehydrogenase subunit I (ND-I), and morphological data using parsimony. A worldwide distribution of Pisciolidae was represented for the first time in a phylogenetic analysis. While the family Piscicolidae was supported as a monophyletic group, the traditional subfamilies based on morphology were not supported. The Platybdellinae was polyphyletic and formed four distinct clades, and Bathybdella sawyeri did not group with any other platybdellids. The Piscicolinae was also polyphyletic, also forming four distinct clades. The pontobdellid genus Stibarobdella was ...