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Full-Text Articles in Life Sciences

Adaptation Of H Pylori To Changing Environments Based On Allelic Variation Of Sensor Histidine Kinase Arss, Monique R. Bennett Jan 2014

Adaptation Of H Pylori To Changing Environments Based On Allelic Variation Of Sensor Histidine Kinase Arss, Monique R. Bennett

Dissertations, Theses, and Masters Projects

No abstract provided.


Impact Of Mercury Exposure On Birds And The Effect Of Molt On Mercury Depuration In Songbirds, Margaret Crossley Whitney Jan 2014

Impact Of Mercury Exposure On Birds And The Effect Of Molt On Mercury Depuration In Songbirds, Margaret Crossley Whitney

Dissertations, Theses, and Masters Projects

No abstract provided.


Effects Of Sub Lethal Methylmercury Exposure On Pigment Coloration In A Model Songbird, Jessica Lynn Spickler Jan 2014

Effects Of Sub Lethal Methylmercury Exposure On Pigment Coloration In A Model Songbird, Jessica Lynn Spickler

Dissertations, Theses, and Masters Projects

No abstract provided.


A Biogeochemical Data Assimilative Modeling Study In The Mid-Atlantic Bight, Yongjin Xiao Jan 2014

A Biogeochemical Data Assimilative Modeling Study In The Mid-Atlantic Bight, Yongjin Xiao

Dissertations, Theses, and Masters Projects

Continental shelves are generally believed to play a critical role in ocean biogeochemical cycling, however this has raised the question as to the relative importance of various nitrogen flux terms such as denitrification, burial, net community production and advective fluxes. Quantifying these fluxes on an annual area-integrated basis using traditional observational means is often difficult, due to the fact that these fluxes rapidly change on relatively small spatial scales, making inadequate data resolution a significant problem. Satellite remote sensing data and numerical modeling provide alternative ways to fill the data gaps, and hence have the potential to generate quantitative estimates ...


Structure, Drivers, And Trophic Interactions Of The Demersal Fish Community In Chesapeake Bay, Andre Buchheister Jan 2014

Structure, Drivers, And Trophic Interactions Of The Demersal Fish Community In Chesapeake Bay, Andre Buchheister

Dissertations, Theses, and Masters Projects

Management of fisheries resources is increasingly broadening its scope from single-species approaches to more holistic, ecosystem-based approaches that account for interactions of fish with a variety of ecological factors, such as predators, prey, and habitat. This ecosystem based fisheries management (EBFM) approach requires thorough biological and ecological understanding of systems pertaining to community structure, habitat suitability, and food web interactions. to strengthen the ecological underpinnings of EBFM efforts in Chesapeake Bay, the largest estuary in the USA, I conducted synoptic analyses examining the structure, function, and patterns of the bay's demersal fish community. This research relied on I0 years ...


The Fruits Of Their Labors: Exploring William Hamilton's Greenhouse Complex And The Rise Of American Botany In Early Federal Philadelphia, Sarah Jane Chesney Jan 2014

The Fruits Of Their Labors: Exploring William Hamilton's Greenhouse Complex And The Rise Of American Botany In Early Federal Philadelphia, Sarah Jane Chesney

Dissertations, Theses, and Masters Projects

This dissertation explores the world of early American botany and the transatlantic community of botanical enthusiasts from the perspective of William Hamilton, gentleman botanical collector in late eighteenth and early nineteenth century Philadelphia. Drawing on both existing documentary sources and three seasons of archaeological excavation at The Woodlands, Hamilton's country estate on the west bank of the Schuylkill River, I analyze both the physical requirements of botanical collecting as well as the more nuanced social, cultural, and economic elements of this trade and its early modern participants.;The personal experiences of individual participants in this exchange are often traced ...


Physiological Stress And Post-Release Mortality Of White Marlin (Kajikia Albida) Caught In The U.S Recreational Fishery, Lela Sylvia Schlenker Jan 2014

Physiological Stress And Post-Release Mortality Of White Marlin (Kajikia Albida) Caught In The U.S Recreational Fishery, Lela Sylvia Schlenker

Dissertations, Theses, and Masters Projects

White Marlin (Kajikia albida) is a highly migratory species that occurs throughout temperate and tropical regions of the Atlantic Ocean and is the basis of a large sport fishery along the United States Atlantic coast. The single, Atlantic-wide stock is considered to be overfished, with less than one-third the spawning biomass estimated to be necessary for maximum sustainable yield. Billfish management measures adopted by the International Commission for the Conservation of Atlantic Tunas (ICCAT) and implemented in the U.S. by the National Marine Fisheries Service (NMFS), as well as increasing angler awareness of conservation, have resulted in the vast ...


Long-Term Change In Copepod Community Structure In The Western Antarctic Peninsula: Linkage To Climate And Implications For Carbon Cycling, Miram Rayzel Gleiber Jan 2014

Long-Term Change In Copepod Community Structure In The Western Antarctic Peninsula: Linkage To Climate And Implications For Carbon Cycling, Miram Rayzel Gleiber

Dissertations, Theses, and Masters Projects

Copepods are the dominant mesozooplankton in the Southern Ocean, but long- term change in their abundance and distribution along the Western Antarctic Peninsula (WAP), a region experiencing rapid climate warming, is unknown. Copepods are also potentially important grazers of phytoplankton in the WAP and contributors to carbon export through production of sinking fecal pellets. I examined summer (January- February) copepod community structure and abundance along the WAP over two decades (1993-2013) and investigated long-term trends in copepod abundance and their relationship with environmental parameters (sea ice, phytoplankton biomass and productivity, climate indices, and sea surface temperature). Copepods comprised on average ...


A Novel Test Of The Immunocompetence Handicap Hypothesis, Jessica H. Ebers Jan 2014

A Novel Test Of The Immunocompetence Handicap Hypothesis, Jessica H. Ebers

Dissertations, Theses, and Masters Projects

No abstract provided.


Rise Of A Floater Class: Behavioral Adjustments By Breeding Bald Eagles In A Population Approaching Saturation, Courtney L. Turrin Jan 2014

Rise Of A Floater Class: Behavioral Adjustments By Breeding Bald Eagles In A Population Approaching Saturation, Courtney L. Turrin

Dissertations, Theses, and Masters Projects

No abstract provided.


The Roles Of Dispersal And Predation In Determining The Seedling Recruitment Patterns Of A Zostera Marina System, Stephen R. Manley Jan 2014

The Roles Of Dispersal And Predation In Determining The Seedling Recruitment Patterns Of A Zostera Marina System, Stephen R. Manley

Dissertations, Theses, and Masters Projects

Seed dispersal and seed predation are two important processes in the early life history of plants. The interaction between these two processes influences the population recruitment from a parent plant. These mechanisms have been studied extensively in terrestrial plants and have resulted in various models to describe plant recruitment (e.g. Janzen-Connell, Hubbell, McCanny). However, seed dispersal and predation may also influence the population recruitment of marine angiosperms, such as Zostera marina (eelgrass). The objectives of this study were to determine: 1.) the patterns of seed dispersal as a function of distance from the seed source, 2.) the predation pressure ...


Seasonal Movements, Habitat Utilization, And Comparative Scale Morphology Of White Marlin (Kajikia Albida) And Roundscale Spearfish (Tetrapturus Georgii), Emily L. Loose Jan 2014

Seasonal Movements, Habitat Utilization, And Comparative Scale Morphology Of White Marlin (Kajikia Albida) And Roundscale Spearfish (Tetrapturus Georgii), Emily L. Loose

Dissertations, Theses, and Masters Projects

Recent studies have demonstrated that the morphologically similar white marlin (Kajikia albida) and roundscale spearfish (Tetrapturus georgii) co-occur in the western North Atlantic, including the U.S. Mid‐Atlantic Bight. Differences in scale morphology have been proposed as one morphological character to discriminate these species, but a thorough analysis of scale morphology is lacking. Because the validity of the roundscale spearfish was not established until 2006, much of the biological information previously collected for “white marlin” may include data for both white marlin and roundscale spearfish. The objectives of this study were to obtain a better understanding of the movements ...


Pain Perception And Perspective Taking In Spinal Cord Injury Patients, Caitlin J. Duckett Jan 2014

Pain Perception And Perspective Taking In Spinal Cord Injury Patients, Caitlin J. Duckett

Dissertations, Theses, and Masters Projects

No abstract provided.


Phylogenetic Systematics Of The Prickleback Family Stichaeidae (Cottiformes: Zoarcoidei) Using Morphological Data, Todd R. Clardy Jan 2014

Phylogenetic Systematics Of The Prickleback Family Stichaeidae (Cottiformes: Zoarcoidei) Using Morphological Data, Todd R. Clardy

Dissertations, Theses, and Masters Projects

The prickleback family Stichaeidae, as currently recognized, is a diverse group of small (<30 cm TL) eel- or blenny-like marine fishes distributed in intertidal, subtidal, and continental slope waters of the North Pacific, Arctic, and North Atlantic oceans. Stichaeidae is one of nine families within the Cottiformes suborder Zoarcoidei and includes six subfamilies, 38 genera, and about 80 species. However, there are questions regarding the monophyly of the family and its position within Zoarcoidei, due in part to a lack of fundamental descriptive anatomical data for the family. The first chapter of my dissertation describes the osteology of Xiphister, a genus of Stichaeidae that includes two species, X. atropurpureus and X. mucosus, found in intertidal and subtidal waters from southern Alaska to southern California. I describe and illustrate their skeletal anatomy, clarify aspects of their anatomy discussed by previous researchers, and describe for the first time elements such as the hyoid and gill arches, scales, and the development of their lateral line canals. These data establish a foundation for the further anatomical and systematic studies of Stichaeidae, and Zoarcoidei generally. Some members of Stichaeidae, including both species of Xiphister , have multiple lateral line canals on their trunk, which is a feature found in only 15 families of teleostean fishes. In the second chapter of my dissertation, the structure and ontogeny of lateral line canals of both species of Xiphister were studied using cleared & stained specimens and histology. Both species have seven cephalic canals and three paired canals on the trunk located on the dorsolateral, mediolateral, and ventrolateral body surfaces. The ventrolateral canal also includes a short loop across the ventral surface of the abdomen. The trunk canals and four short branches of the infraorbitals that extend across the cheek are supported by small ossified rings. The trunk canals develop asynchronously and separately from the development of scales, suggesting that the ossified rings that support the canals are not modified scales. Results from histology show that neuromasts, the sensory components of the mechanosensory system, are found only in the cephalic, dorsolateral, and mediolateral canals; the ventrolateral canal and its loop lack neuromasts. The evolution and functional role of multiple trunk lateral line canals is discussed. The third chapter of my dissertation examines the phylogenetic systematics of Stichaeidae using 106 morphological characters and 60 terminal taxa, including 30 genera of Stichaeidae, representatives from all eight other families of Zoarcoidei, and additional outgroup taxa. The suborder Zoarcoidei was recovered as a monophyletic group sister to Cottoidei within the order Cottiformes. Within Zoarcoidei, however, the family Stichaeidae was not recovered as a monophyletic family. Only two of the six subfamilies within Stichaeidae, Lumpeninae and Neozoarcinae, were recovered as monophyletic. The high level of homoplasy in the remaining four stichaeid subfamilies, and the inclusion of zoarcoid families nested within Stichaeidae, suggests that the current classification of Stichaeidae does not accurately reflect the evolutionary history of Zoarcoidei.


New Insights Into Fibrous Body Protein Complexes Involved In C Elegans Spermatogenesis, Christopher M. Uyehara Jan 2014

New Insights Into Fibrous Body Protein Complexes Involved In C Elegans Spermatogenesis, Christopher M. Uyehara

Dissertations, Theses, and Masters Projects

No abstract provided.


Natural Variation In Fertility And Gnrh Neurons In A Wild, Natural Population Of White-Footed Mice, Peromyscus Leucopus, Melissa Proffitt Jan 2014

Natural Variation In Fertility And Gnrh Neurons In A Wild, Natural Population Of White-Footed Mice, Peromyscus Leucopus, Melissa Proffitt

Dissertations, Theses, and Masters Projects

No abstract provided.


Using Human Footprint Models And Land-Cover Variability To Predict Ecological Processes, Jessica Anne Pouder Jan 2014

Using Human Footprint Models And Land-Cover Variability To Predict Ecological Processes, Jessica Anne Pouder

Dissertations, Theses, and Masters Projects

No abstract provided.


Using A Sonic Net To Deter Pest Bird Species: Excluding European Starlings From Food Sources By Disrupting Their Acoustic Environment, Ghazi Mahjoub Jan 2014

Using A Sonic Net To Deter Pest Bird Species: Excluding European Starlings From Food Sources By Disrupting Their Acoustic Environment, Ghazi Mahjoub

Dissertations, Theses, and Masters Projects

No abstract provided.


Anthropogenic Modifications Of Connectivity At The Aquatic-Terrestrial Ecotone In The Chesapeake Bay, Robert Earl Isdell Jan 2014

Anthropogenic Modifications Of Connectivity At The Aquatic-Terrestrial Ecotone In The Chesapeake Bay, Robert Earl Isdell

Dissertations, Theses, and Masters Projects

No abstract provided.


Identifying Sumo Protease Targets And Investigating E3 Ligase Interactions, Mark Guillotte Jan 2014

Identifying Sumo Protease Targets And Investigating E3 Ligase Interactions, Mark Guillotte

Dissertations, Theses, and Masters Projects

No abstract provided.