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Life History Of Stranded Bottlenose Dolphins (Tursiops Truncatus) In Virginia, Margaret Cook Lynott Oct 2012

Life History Of Stranded Bottlenose Dolphins (Tursiops Truncatus) In Virginia, Margaret Cook Lynott

Biological Sciences Theses & Dissertations

Little is known about the life history and overall ecology of bottlenose dolphins that strand in Virginia. In this study, I examined archived life history samples and stranding data from bottlenose dolphins found in Virginia waters to (1) develop growth curves based on ages from sectioned teeth, (2) document characteristics of male and female reproductive organs, and (3) define the relationship between age/length and presence of neonatal characteristics during the first year of life. The Gompertz growth model provided the best fit of growth data for stranded T. truncatus in Virginia. Length at birth and asymptotic length for males were …


Evolution On The Hawaiian Hotspot: Biogeography And Divergence Time Estimation Of Kadua (Rubiaceae), Kenneth L. Parker Oct 2012

Evolution On The Hawaiian Hotspot: Biogeography And Divergence Time Estimation Of Kadua (Rubiaceae), Kenneth L. Parker

Biological Sciences Theses & Dissertations

Recent studies on the colonization time of Hawaiian plant and animal lineages have suggested certain lineages arrived to the archipelago before the formation of the extant islands. Kadua, a recently resurrected genus, is mostly endemic to the Hawaiian Archipelago, with many member taxa autochthonous to individual islands. This work investigates the colonization time of Kadua to the Hawaiian Islands. Sequence analyses of the quickly evolving nuclear regions ITS, ETS and 5s-NTS regions for 20 Hawaiian and 7 French Polynesian species of Kadua were used to create dated phylogeny calibrated with island ages. The phylogeny suggests a single colonization of Hawaii …


Thresholds Of Change In Decomposition Rate Along A Dune/Swale Transect On A Virginia Barrier Island, Dominic J. Graziani Oct 2012

Thresholds Of Change In Decomposition Rate Along A Dune/Swale Transect On A Virginia Barrier Island, Dominic J. Graziani

Biological Sciences Theses & Dissertations

Aboveground and belowground decomposition rates were determined along a barrier island dune/swale transect located on the Virginia Coast Reserve-Long Term Ecological Research Site using litterbags and wooden dowels. The objective was to determine the influence of fine scale changes in the environment on decomposition to identify any potential thresholds affecting decomposition rate. Wax myrtle (Morella cerifera L. Small) leaves and dowels of southern yellow pine wood were used as standard substrates to evaluate environmental influences on decay. Aboveground (F=6.494, p < 0.0001) and belowground (F=5.705, p < 0.0001) decay rates (yr-1) showed significant variation among litterbag/dowel locations. Aboveground decay rates (yr-1) ranged from 0.339 (Upper Dune station) …


Fecal Indicator Bacteria In Knitting Mill Creek With A Comparison Of Methods Used To Enumerate E. Coli, Manju Nagarajan Oct 2012

Fecal Indicator Bacteria In Knitting Mill Creek With A Comparison Of Methods Used To Enumerate E. Coli, Manju Nagarajan

OES Theses and Dissertations

This research seeks to evaluate the impact of an urban, multi-use neighborhood on the bacteriological quality of water in Knitting Mill Creek, a blind arm of the Lafayette River, a sub-estuary of the lower Chesapeake Bay. A principal objective was to determine the effects of rainfall, a surrogate for run-off, on water-column concentrations of fecal-indicator bacteria (FIB). I collected water samples weekly (September 2009-December 2010) and biweekly (January 2010-December 2011) at a storm-sewer outfall and a nearby marina and quantified their E. coli and enterococci concentrations using Colilert-18 and Enterolert, most-probable-number assays. In addition, I took monthly samples for these …


Guardians Of The Countryside Public Choice Theory And The Farm Lobby In The Eu's Common Agricultural Policy, Amy J. Costa Aug 2012

Guardians Of The Countryside Public Choice Theory And The Farm Lobby In The Eu's Common Agricultural Policy, Amy J. Costa

Graduate Program in International Studies Theses & Dissertations

Through various waves of reform, the European Union's Common Agricultural Policy remains inefficient without meeting all of its stated goals. The MacSherry reforms of 1992 resulted in the opposite of what leaders intended: higher spending and a growing bureaucracy. Later in the 1990s, Agenda 2000 slashed its originally planned cutbacks after farmers protested. Though support exists for reducing spending on agriculture, market intervention remains.

This thesis explores the problem through the use of public choice theory. -Consumers make too large a group to organize effectively or inform themselves about the issue, while farmers consist of a smaller group with well-defined …


Multilevel Analysis Of Physical Activity Among Us Adults Across Us Census Regions: The Role Of Environmental Contexts, Sariyamon Tiraphat Jul 2012

Multilevel Analysis Of Physical Activity Among Us Adults Across Us Census Regions: The Role Of Environmental Contexts, Sariyamon Tiraphat

Health Services Research Dissertations

This study uses nationally representative data to explain the variation in physical activity among U.S. adults across four geographic regions of Northeast, Midwest, South, and West. The purpose of the study is to investigate whether environmental conditions inclusive of natural amenity, built environment, urbanization, crime, and social economic neighborhood are associated with physical activity and whether these associations are modified by geographic region. The study also investigates whether the influences of environmental contexts vary by subgroup and whether they are modified by geographic region. Determining regional factors that influence physical activity is essential to planning appropriate physical activity interventions.

The …


A Statistical Model To Determine Multiple Binding Sites Of A Transcription Factor On Dna Using Chip-Seq Data, Rasika Jayatillake Jul 2012

A Statistical Model To Determine Multiple Binding Sites Of A Transcription Factor On Dna Using Chip-Seq Data, Rasika Jayatillake

Mathematics & Statistics Theses & Dissertations

Protein-DNA interaction is vital to many biological processes in cells such as cell division, embryo development and regulating gene expression. Chromatin Immunoprecipitation followed by massively parallel sequencing (ChIP-seq) is a new technology that can reveal protein binding sites in genome with superior accuracy. Although many methods have been proposed to find binding sites for ChIP-seq data, they can find only one binding site within a short region of the genome. In this study we introduce a statistical model to identify multiple binding sites of a transcription factor within a short region of the genome using the ChIP-seq data. Mapped sequence …


De Novo Protein Structure Modeling From Cryoem Data Through A Dynamic Programming Algorithm In The Secondary Structure Topology Graph, Kamal H. Al Nasr Jul 2012

De Novo Protein Structure Modeling From Cryoem Data Through A Dynamic Programming Algorithm In The Secondary Structure Topology Graph, Kamal H. Al Nasr

Computer Science Theses & Dissertations

Proteins are the molecules carry out the vital functions and make more than the half of dry weight in every cell. Protein in nature folds into a unique and energetically favorable 3-Dimensional (3-D) structure which is critical and unique to its biological function. In contrast to other methods for protein structure determination, Electron Cryorricroscopy (CryoEM) is able to produce volumetric maps of proteins that are poorly soluble, large and hard to crystallize. Furthermore, it studies the proteins in their native environment. Unfortunately, the volumetric maps generated by current advances in CryoEM technique produces protein maps at medium resolution about (~5 …


Identification Of Persistent Long Range Interactions In GA95 And GB95 Through Thermal Unfolding Simulations, Milen Redai Tesfamariam Jul 2012

Identification Of Persistent Long Range Interactions In GA95 And GB95 Through Thermal Unfolding Simulations, Milen Redai Tesfamariam

Chemistry & Biochemistry Theses & Dissertations

For over five decades, different experiments have been performed to research how proteins attain their native three dimensional structures. However, the folding problem continues to be a puzzle in modern science. The design of two proteins that have maximal sequence identity but different folds and functions is one method that is being used to study the relationship between protein structure and amino acid sequence. In particular, mutant proteins of Streptococcus protein G, GA and GB, have 95% sequence identity and a 3a helix fold and β4/a fold, respectively. Molecular dynamics simulations of GA95 …


Assessing Movement Of Fish Through Spectral Analysis Of Otolith Life History Scans, Renee Reilly Hoover Jul 2012

Assessing Movement Of Fish Through Spectral Analysis Of Otolith Life History Scans, Renee Reilly Hoover

OES Theses and Dissertations

The ability to accurately measure movement timing across environmental gradients is fundamental for testing hypotheses in marine ecology that deal with ingress, egress, and migration of fish. Timing and patterns of movement have been estimated using life-history scans of the chemical signatures encoded in fish otoliths (ear stones). I provide a quantitative approach to examining life history scan data using spectral analysis, which retrospectively measures the movement timing for individual fish. Sagittal otoliths from juvenile Atlantic croaker (Micropogonias undulates) and adult black sea bass (Centropristis striata) were sampled using laser ablation inductively coupled plasma mass spectrometry …


Population Structure And Connectivity Of An Important Pelagic Forage Fish In The Antarctic Ecosystem, Pleuragramma Antarcticum In Relation To Large Scale Circulation, Jason W. Ferguson Jul 2012

Population Structure And Connectivity Of An Important Pelagic Forage Fish In The Antarctic Ecosystem, Pleuragramma Antarcticum In Relation To Large Scale Circulation, Jason W. Ferguson

OES Theses and Dissertations

Ocean circulation has been identified as a major process controlling the distribution of biological material in marine systems. Large-scale transport by the Antarctic Circumpolar Current (ACC), the Ross and Weddell Gyres, and the Antarctic Coastal Current can promote spatially complex population structure in the Southern Ocean through advection. Antarctic silverfish (Pleuragramma antarcticum), a pelagic, neutrally buoyant notothenioid fish species, are distributed around the shelf systems of Antarctica and are considered an important species rivaling krill as prey for many birds, seals, whales, and other fish. We asked whether silverfish are distributed in independent, discrete populations along the shelf systems of …


The Influence Of Interlimb Differences On Anterior Cruciate Ligament Injury Risk Factors In Female Collegiate Soccer Athletes, Eric Kevin Greska Apr 2012

The Influence Of Interlimb Differences On Anterior Cruciate Ligament Injury Risk Factors In Female Collegiate Soccer Athletes, Eric Kevin Greska

Human Movement Sciences & Special Education Theses & Dissertations

Female collegiate soccer athletes suffer anterior cruciate ligament (ACL) injuries at a rate of 0.31 per 1000 athlete-exposures, with 67% of injuries expected to be from a non-contact mechanism. As well, previous studies have demonstrated dissimilarity in non-contact ACL injuries relative to dominant and non-dominant legs; with the non-dominant leg being the involved side in 48-67% of reported incidents. The aim of this study was to examine lower extremity neuromechanics relative to leg dominance during an unanticipated sidestep cutting task, with differing states of fatigue and training.

Twenty female collegiate soccer players performed three valid trials for both the dominant …


Effects Of The Parasitic Dinoflagellate Hematodinium Sp. On Blue Crab (Callinectes Sapidus) Activity Predation And Habitat Selection, John M. Tiggelaar Ii Apr 2012

Effects Of The Parasitic Dinoflagellate Hematodinium Sp. On Blue Crab (Callinectes Sapidus) Activity Predation And Habitat Selection, John M. Tiggelaar Ii

Biological Sciences Theses & Dissertations

The blue crab Callinectes sapidus occurs along the Atlantic and Gulf coasts of the United States, and in high salinity regions, they are subject to lethal infection by the parasitic dinoflagellate Hematodinium. In Virginia's seaside estuaries, the prevalence of Hematodinium infection of C. sapidus can sometimes exceed 50%, threatening the commercial fishery for this species. Indeed, other commercially important crustacean fisheries have approached collapse due to Hematodinium infections. Most studies of this host-parasite interaction have focused on epidemiology, host-pathogen dynamics, and pathogen transmission, and little is known about the impact of the parasite on host behavior and population dynamics. …


Modeling The Dispersion Of Eastern Oyster Larvae (Crassostrea Virginica) And Its Effects On The Movement Of Disease Resistant Genes In The Delaware Bay Estuary, Diego A. Narvaez Apr 2012

Modeling The Dispersion Of Eastern Oyster Larvae (Crassostrea Virginica) And Its Effects On The Movement Of Disease Resistant Genes In The Delaware Bay Estuary, Diego A. Narvaez

OES Theses and Dissertations

This study combines several models to address two primary research questions. How does the interaction of larval biology and environmental variability determine the spatial distribution of oyster larvae in Delaware Bay? What is the role of larval dispersion in the transference of disease-resistant genes? The particle-tracking module in the Regional Ocean Modeling System (ROMS) was converted into an Individual-Based model representing Eastern oyster larvae that has growth and vertical migration. Exchange of larvae between natural oyster reefs was estimated and used in an Individual-Based genetic model that simulates the genetic structure of eastern oysters. Particles were released from a number …


Design Of In Vivo Assays For Study Of Transport, Biocompatibility And Toxicity Of Nanoparticles, Kerry Jean Lee Apr 2012

Design Of In Vivo Assays For Study Of Transport, Biocompatibility And Toxicity Of Nanoparticles, Kerry Jean Lee

Theses and Dissertations in Biomedical Sciences

This dissertation focuses on the design of new in vivo assays for study of transport, biocompatibility and toxicity of nanoparticles (NPs) in zebrafish embryos. We synthesized and purified spherical silver (Ag) NPs with diameters, ranging from 12 to 95 nm, that are stable (non-aggregated) in egg-water media. We developed new imaging approaches to characterize the sizes of single Ag NPs in zebrafish embryos at nanometer resolution by measuring their size-dependent plasmonic spectra and scattering intensity using dark-field optical microscopy and spectroscopy (DFOMS). We used single Ag NPs because they exhibit the high quantum yield (QY) of Rayleigh scattering and resist …


The Dietary Isoprenoid Perillyl Alcohol Inhibits Telomerase Activity In Prostate Cancer Cells, Tabetha Sundin Apr 2012

The Dietary Isoprenoid Perillyl Alcohol Inhibits Telomerase Activity In Prostate Cancer Cells, Tabetha Sundin

Theses and Dissertations in Biomedical Sciences

This is the first evidence that a plant-derived compound–perillyl alcohol regulates telomerase activity via the mammalian target of rapamycin (mTOR) pathway in prostate cancer cells. Telomerase–the enzyme responsible for immortalizing cells through telomeric repeats addition–is de-repressed early in an aspiring cancer cell. We hypothesized that perillyl alcohol regulates hTERT (human telomerase reverse transcriptase) at the translational and post-translational levels via its effects on the mTOR pathway. A rapid suppression of telomerase activity was detected in prostate cancer cell lines (PC-3 and DU145) in response to biologically-relevant concentrations and short incubations of perillyl alcohol or the mTOR inhibitor—rapamycin.

Western blot analysis …


Treatment Of Aortic Heart Valve Conduit With Glutamine And Heat Shock As A Means To Deter The Constituent Cellular Population From Becoming Apoptotic, Alyce Marie Linthurst Jones Apr 2012

Treatment Of Aortic Heart Valve Conduit With Glutamine And Heat Shock As A Means To Deter The Constituent Cellular Population From Becoming Apoptotic, Alyce Marie Linthurst Jones

Theses and Dissertations in Biomedical Sciences

Cryopreserved allograft heart valves represent the best solution for a patient with a failing heart valve. However, the constituent cells become apoptotic and within months of transplant the heart valve becomes acellular and the recipient's cells do not repopulate the allograft (3, 51). A strategy to prevent this situation would be to minimize or prevent apoptosis from occurring by strategically altering steps during heart valve processing. Recently it has been demonstrated that: 1) Heat shock protein 70 is a negative modulator of the apoptotic cascade; 2) Cells in culture exposed to hypothermic conditions produce heat shock protein 70 upon rewarming; …


Nano- And Micro-Second Electrical Pulsing Of B16-F10 Mouse Melanoma Cells: Plasma Membrane And Sub-Cellular Organelle Changes, Yiling Chen Apr 2012

Nano- And Micro-Second Electrical Pulsing Of B16-F10 Mouse Melanoma Cells: Plasma Membrane And Sub-Cellular Organelle Changes, Yiling Chen

Theses and Dissertations in Biomedical Sciences

High electric field-treated cells are permeable to molecular dye through either opening of pores in the plasma membrane or other unknown processes which can disturb the membrane in an organized way. However, direct morphological evidence is lacking and responses of intracellular organelles are not clear. We used traditional chemical fixatives and biochemical techniques to capture cell membrane and organelle changes immediately after pulsing with high voltage electric field application. Different pulse durations, nanosecond (ns) and microsecond (µs), and field magnitudes, 60 kV/cm and 1.2 kV/cm, were applied to mouse melanoma B16-F10 cells. Two different ns durations (60 and 300 ns) …


Evidence-Based Practice For The Athletic Training Profession, Cailee Elizabeth Welch Apr 2012

Evidence-Based Practice For The Athletic Training Profession, Cailee Elizabeth Welch

Human Movement Sciences & Special Education Theses & Dissertations

As evidence-based practice (EBP) becomes a necessity in athletic training, it is essential to recognize current barriers and modes of accessibility to information for enhancement of clinical decision-making. Furthermore, the effectiveness of educational interventions (EI) to enhance knowledge of EBP concepts must be investigated. The aim of Project I was to assess attitudes and beliefs, perceived barriers, and accessibility to resources of EBP among athletic trainers (AT). Project II was designed to investigate the effect of an EI on enhancing AT's knowledge of EBP concepts. Project III explored ATs' experiences of the EI and whether it elicited changes within their …


Ecology Of Tenodera Sinensis And Tenodera Angustipennis (Mantodea: Mantidae) In Eastern Virginia, Cory A. Gall Apr 2012

Ecology Of Tenodera Sinensis And Tenodera Angustipennis (Mantodea: Mantidae) In Eastern Virginia, Cory A. Gall

Biological Sciences Theses & Dissertations

My study, conducted on the Wildlife Refuge located on Virginia's Eastern Shore, focused on the life history, ecology, and intra- and interspecies interaction of Tenodera sinensis and T. angustipennis. Field methods included capture-mark-recapture, species, sex, and developmental life stage identification, and recorded key developmental milestones. Also, to analyze food-limiting growth, a laboratory cohort was fed ad lib, with lab and field cohorts measured bi-weekly and their mean weekly growth was compared.

When compared to a lab cohort, Tsinensis field mantises were shown not to be growth limited by the abundance of prey. In 2011, the dates of several developmental stages …


Alternative Therapy And Treatment Of Type 2 Diabetes, Carmine R. Grieco Apr 2012

Alternative Therapy And Treatment Of Type 2 Diabetes, Carmine R. Grieco

Human Movement Sciences & Special Education Theses & Dissertations

The rise in prevalence and incidence of type 2 diabetes mellitus (T2D) in the developing world continues unabated. Current treatment strategies, however, fall short of achieving optimal glycemic control. The aim of project I was to investigate the effect of an acute bout of a yogic breathing exercise on heart rate variability (HRV) in individuals with T2D. Project II was designed to assess the effectiveness of the neurohormone melatonin in lowering short- and long-term glucose levels, lipids and oxidative stress in T2D. Project III investigated the differential effects of two different styles of aerobic exercise on postprandial glycemia, mood and …


Nonosecond Pulsed Electric Field Induced Changes In Dielectric Properties Of Biological Cells, Jie Zhuang Apr 2012

Nonosecond Pulsed Electric Field Induced Changes In Dielectric Properties Of Biological Cells, Jie Zhuang

Electrical & Computer Engineering Theses & Dissertations

Nanosecond pulsed electric field induced biological effects have been a focus of research interests since the new millennium. Promising biomedical applications, e.g. tumor treatment and wound healing, are emerging based on this principle. Although the exact mechanisms behind the nanosecond pulse-cell interactions are not completely understood yet, it is generally believed that charging along the cell membranes (including intracellular membranes) and formation of membrane pores trigger subsequent biological responses, and the number and quality of pores are responsible for the cell fate. The immediate charging response of a biological cell to a nanosecond pulsed electric field exposure relies on the …


Eukaryotic Microbes In The Deep Sea: Abundance, Diversity, And The Effect Of Pressure, Danielle Morgan-Smith Jan 2012

Eukaryotic Microbes In The Deep Sea: Abundance, Diversity, And The Effect Of Pressure, Danielle Morgan-Smith

OES Theses and Dissertations

The dark ocean is vast, high in pressure, cold, and scarce in resources, but has been shown to support a diverse and active microbial community wherever it is studied. Such studies, however, are scarce due to the difficulty of sampling at such depths, and are difficult to interpret due to compounding effects of pressure and temperature on physiology. Protists, functionally defined as the microbial portion of the domain Eukarya, are particularly neglected in studies of deep-sea microbiology. Here, I present three studies on microbial eukaryotes in the deep sea: first, a study of the abundance of microbial eukaryotes in the …


Optimizing Chronic Slow Breathing Training To Cause A Therapeutic Effect On Heart Rate Variability, Jennifer Joy Brown Jan 2012

Optimizing Chronic Slow Breathing Training To Cause A Therapeutic Effect On Heart Rate Variability, Jennifer Joy Brown

Human Movement Sciences & Special Education Theses & Dissertations

Heart rate variability (HRV) is a valid and reliable tool that can be used to determine the basic state of an individual's autonomic health. The current study attempted to establish the minimum frequency of breathing practice necessary to produce a therapeutic effect on HRV over the course of a four-week period with four different treatment groups, specifically, groups that practiced a slow breathing protocol for either 2, 3 or 5 times per week, and a control group. Forty-three subjects (14 males, 29 females), ages 18–50 years, were screened, pre-tested, matched for sex, age and HRV, assigned to a specific group …


Grazing On Synechococcus Spp. By The Red-Tide Dinoflagellate Karenia Brevis: Implications For Bloom Dynamics In The Gulf Of Mexico, Leo A. Procise Jan 2012

Grazing On Synechococcus Spp. By The Red-Tide Dinoflagellate Karenia Brevis: Implications For Bloom Dynamics In The Gulf Of Mexico, Leo A. Procise

OES Theses and Dissertations

Karenia brevis, the toxic dinoflagellate responsible for massive red tides in the Gulf of Mexico (GOM), causes fish kills, shellfish poisoning, and acute respiratory irritation in humans. Bloom initiation and maintenance have been linked to the physical environment as well as various nutrient input mechanisms. To date, efforts to quantify nitrogen (N) sources fueling K. brevis blooms in the GOM have not included mixotrophic grazing although many dinoflagellates, including K. brevis, are known to be capable of mixotrophy. This dissertation reports field and laboratory results demonstrating that natural bloom populations and K. brevisisolates from the West Florida …