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Enabling Technology For Non-Rigid Registration During Image-Guided Neurosurgery, Andriy Yuri Fedorov
Enabling Technology For Non-Rigid Registration During Image-Guided Neurosurgery, Andriy Yuri Fedorov
Dissertations, Theses, and Masters Projects
In the context of image processing, non-rigid registration is an operation that attempts to align two or more images using spatially varying transformations. Non-rigid registration finds application in medical image processing to account for the deformations in the soft tissues of the imaged organs. During image-guided neurosurgery, non-rigid registration has the potential to assist in locating critical brain structures and improve identification of the tumor boundary. Robust non-rigid registration methods combine estimation of tissue displacement based on image intensities with the spatial regularization using biomechanical models of brain deformation. In practice, the use of such registration methods during neurosurgery is …
Anthropogenic Causes Of Copepod Mortality And Bacterial Decomposition Of Copepod Carcasses, Samantha L. Bickel
Anthropogenic Causes Of Copepod Mortality And Bacterial Decomposition Of Copepod Carcasses, Samantha L. Bickel
Dissertations, Theses, and Masters Projects
Although zooplankton carcasses can be quite prevalent within aquatic systems, they have largely been overlooked in most zooplankton population studies. Anthropogenic stressors can potentially increase the overall abundance of carcasses on a local scale. Once a carcass is present within a system, the fate of its biomass is of considerable interest as it may be remineralized within the water column or transported to depth. Through the collection of field samples I assessed the possibility of an anthropogenic stressor (boat-generated turbulence) as a potential source of nonconsumptive mortality. I also conducted a series of laboratory experiments to monitor the decomposition of …
Variability In Juvenile Growth, Mortality, Maturity, And Abundance Of American Shad And Blueback Herring In Virginia, Troy D. Tuckey
Variability In Juvenile Growth, Mortality, Maturity, And Abundance Of American Shad And Blueback Herring In Virginia, Troy D. Tuckey
Dissertations, Theses, and Masters Projects
Young-of-year (YOY) population dynamics of American shad and blueback herring in Virginia's rivers were examined with an emphasis on variability in growth and mortality rates. In addition, an analysis was conducted to relate juvenile abundance indices of American shad to adult indices to establish a stock-recruitment relationship. to accomplish the stock recruitment relationship, an additional study that examined maturation schedules and inter-annual variability in maturation schedules among stocks was performed. Results of population dynamics studies found that growth and mortality rates of American shad and blueback herring varied by river and year and that conspecific abundance was an important factor …
Continental Shelf Sediment Transport And Depositional Processes On An Energetic, Active Margin: The Waiapu River Shelf, New Zealand, Yanxia Ma
Dissertations, Theses, and Masters Projects
The Waiapu River drains a small mountainous basin, characterized by steep terrain, heavy rainfall, and unconsolidated soft Tertiary mudstone and siltstone. These factors, combined with heavy deforestation over the past 100 years have created one of the world's highest sediment yields. Water discharge of the Waiapu River is very episodic over both inter- and intra-annual timescales, and almost all of the discharge is associated with floods brought by cyclonic storms. The Waiapu River drains an active margin that has a narrow shelf and steep slope. Marine conditions on the Waiapu continental shelf are very energetic, with strong waves as well …
Laser Desorption From A Room Temperature Ionic Liquid, Peter Ronald Harris
Laser Desorption From A Room Temperature Ionic Liquid, Peter Ronald Harris
Dissertations, Theses, and Masters Projects
We report laser desorption from a Room Temperature Ionic Liquid (RTIL) as a novel source for time of flight mass spectrometry. We use the 2nd harmonic of an Nd:YAG laser to deposit intensities of 1-50 MW/cm2 via backside illumination onto our RTIL desorption sample. A microstructured metal grid situated on top of a glass microscope slide coated with RTIL serves as our desorption sample. The RTIL we use, 1-Butyl, 3-Methylimidazolium Hexafluorophosphate, remains liquid at pressures below 10-8 torr. The use of liquid desorption sample allows for improved surface conditions, homogeneity and sample life as compared to Matrix Assisted Laser Desorption …
Environmental Analysis Of Selected Estrogens And Androgens: Applying Ultra-Performance Liquid Chromatography And Combating Matrix Interference, Stacie L. Rice
Environmental Analysis Of Selected Estrogens And Androgens: Applying Ultra-Performance Liquid Chromatography And Combating Matrix Interference, Stacie L. Rice
Dissertations, Theses, and Masters Projects
Investigations of environmental hormone contamination commonly utilize solidphase extraction (SPE) followed by high-performance liquid chromatography / (electrospray ionization) tandem mass spectrometry (HPLC/(ESI)MS2) in the detection of estrogens. Matrix interference is widely reported. In this study, androgens were targeted alongside estrogens as environmentally co-introduced endocrine disrupting chemicals. Analytical methods were developed in parallel for detection of several hormones from each class, with comparison of protocols and instrumental parameters. Ultraperformance LC (UPLC®), an emerging technology advertised for reduced retention times, was used in place of HPLC for hormone separation. Applicability to diverse aqueous samples was tested. Matrix interference was combated with two …
Polybrominated Diphenyl Ether Flame Retardants In Birds Of Prey From The U.S. And China, Da Chen
Polybrominated Diphenyl Ether Flame Retardants In Birds Of Prey From The U.S. And China, Da Chen
Dissertations, Theses, and Masters Projects
Polybrominated diphenyl ether (PBDE) flame retardants are widely used as non-reactive additives in textiles, polyurethane foams, plastics, furnishings, and electronic products. as a result of substantial, long-term usages, PBDEs have contaminated humans, wildlife, air, water, soil, and sediment, even in remote areas. Although the North American and Asian (particularly Chinese) markets have consumed the majority of global PBDE production, knowledge about PBDE contamination is limited in these two regions. Therefore, this research aimed to investigate PBDE contamination in some Chinese and North American areas by examining the birds of prey that have been considered as sensitive monitoring species for organochlorine …
Development Of A Storm Surge Model Using A High-Resolution Unstructured Grid Over A Large Domain, Tao Shen
Development Of A Storm Surge Model Using A High-Resolution Unstructured Grid Over A Large Domain, Tao Shen
Dissertations, Theses, and Masters Projects
A quasi-3D storm surge modeling system was developed for forecasting the storm surge and inundation in the Chesapeake Bay. The system was constructed with one large unstructured grid covering the Atlantic Coast from Nova Scotia to Florida and a smaller, limited domain unstructured grid covering the Chesapeake Bay, Virginia Beach, Hampton Roads and the adjacent continental shelf regions. It was demonstrated that, with the large domain grid, the model could simulate the hurricane induced storm surge reasonably well using astronomical tide at the open boundary condition and in turn, provide boundary condition for the limited domain model. Since the difficulty …
Measurement Of The Strange Quark Contribution To The Vector Structure Of The Proton, Sarah Katherine Phillips
Measurement Of The Strange Quark Contribution To The Vector Structure Of The Proton, Sarah Katherine Phillips
Dissertations, Theses, and Masters Projects
The goal of the G0 experiment is to determine the contribution of the strange quarks in the quark-antiquark sea to the structure of the nucleon. to this end, the experiment measured parity-violating asymmetries from elastic electron-proton scattering from 0.12 ≤ Q2 ≤ 1.0 (GeV/ c)2 at Thomas Jefferson National Accelerator Facility. These asymmetries come from the interference of the electromagnetic and neutral weak interactions, and are sensitive to the strange quark contributions in the proton. The results from the forward angle measurement, the linear combination of the strange electric and magnetic form factors GsE + etaGsM, suggest possible non-zero, Q …
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.
Mortality Of Diamondback Terrapins In Blue Crab Traps: Population Changes And Conservation In Southeastern Virginia, Megan Ann Rook
Mortality Of Diamondback Terrapins In Blue Crab Traps: Population Changes And Conservation In Southeastern Virginia, Megan Ann Rook
Dissertations, Theses, and Masters Projects
No abstract provided.
The Synthesis And Spectroscopic Study Of A Spirooxazine-Functionalized Poly(Phenylenevinylene), Jordan Thomas Walk
The Synthesis And Spectroscopic Study Of A Spirooxazine-Functionalized Poly(Phenylenevinylene), Jordan Thomas Walk
Dissertations, Theses, and Masters Projects
No abstract provided.
Cyclization Reactions Catalyzed By Bi(Iii) Compounds, Jia Liu
Cyclization Reactions Catalyzed By Bi(Iii) Compounds, Jia Liu
Dissertations, Theses, and Masters Projects
No abstract provided.
Quantifying The Overwash Component Of Barrier Island Morphodynamics: Onslow Beach, Nc, Amy C. Foxgrover
Quantifying The Overwash Component Of Barrier Island Morphodynamics: Onslow Beach, Nc, Amy C. Foxgrover
Dissertations, Theses, and Masters Projects
A quantification of the role that barrier island overwash plays in the evolution of Onslow Beach, a barrier island located on Marine Corps Base Camp Lejeune, North Carolina, is presented. Ground-penetrating radar (GPR) and sediment vibracores provide an estimate of the relevant-sand prism above a silty/peat contact underlying the island. The average thickness from the surface, as determined from lidar, to this geologically-defined base, is less than 1 m and equates a total volume of approximately 1.8 ± 1.1 × 106 m3 over the 4.8 km stretch of Onslow Beach from 1 km north of the New River Inlet to …
Water Quality In Headwater Streams: A Test Of Best Management Practices, Jonathan Worth Holley
Water Quality In Headwater Streams: A Test Of Best Management Practices, Jonathan Worth Holley
Dissertations, Theses, and Masters Projects
No abstract provided.
Using An Occupancy Modeling Framework To Test The Effects Of Habitat Variables On Pond Occupancy Of Mabee's Salamander (A Mabeei) And Marbled Salamander (A Opacum), Christy Michelle Fairman
Using An Occupancy Modeling Framework To Test The Effects Of Habitat Variables On Pond Occupancy Of Mabee's Salamander (A Mabeei) And Marbled Salamander (A Opacum), Christy Michelle Fairman
Dissertations, Theses, and Masters Projects
No abstract provided.
Songbirds, Pesticides, And Golf Courses: Exposure And Effects, Ryan Brennan Burdge
Songbirds, Pesticides, And Golf Courses: Exposure And Effects, Ryan Brennan Burdge
Dissertations, Theses, and Masters Projects
No abstract provided.
New Developments In Xanthate Ester Chemistry And The Potential For Protecting Group Applications, Matthew Hobson Jones
New Developments In Xanthate Ester Chemistry And The Potential For Protecting Group Applications, Matthew Hobson Jones
Dissertations, Theses, and Masters Projects
No abstract provided.
The Functionalization Of Carbon Nanosheets, Ronald A. Quinlan
The Functionalization Of Carbon Nanosheets, Ronald A. Quinlan
Dissertations, Theses, and Masters Projects
Carbon nanosheets are a novel two-dimensional nanostructure made up of 2-20 graphene atomic planes oriented with their in-plane axis perpendicular to the growth substrate. Previous efforts in developing nanosheet technology have focused on the characterization of the system and their development as an electron source due to the high atomic enhancement factor (beta) and low turn on field. Further investigation of nanosheets as high surface area electrodes revealed poor wetting by polymeric material and extreme hydrophobic behavior.;Because nanosheet technology has promise as a high surface area electrode material, this thesis research has focused on three areas of interest: the enhancement …
Topics In Particle Physics Beyond The Standard Model, Brian Audley Glover
Topics In Particle Physics Beyond The Standard Model, Brian Audley Glover
Dissertations, Theses, and Masters Projects
We present new models of particle physics beyond the Standard Model. These models include extensions to the ideas of extra dimensions, deconstruction, supersymmetry, and Higgsless electroweak symmetry breaking. Besides introducing new models and discussing their consequences, we also discuss how galaxy cluster surveys can be used to constrain new physics beyond the Standard Model.;We find that an ultraviolet completion of gauge theories in the Randall-Sundrum model can be found in a deconstructed theory. The warping of the extra dimension is reproduced in the low energy theory by considering a general potential for the link fields with translational invariance broken only …
The Effect Of Realistic Focal Conditions On Strong -Field Double Ionization, Jay Paul Paquette
The Effect Of Realistic Focal Conditions On Strong -Field Double Ionization, Jay Paul Paquette
Dissertations, Theses, and Masters Projects
In recent years, a great deal of progress has been made in understanding the ionization processes that result from the interaction of an intense laser pulse with multielectron atoms. However, due to experimental limitations, the effect of the laser field's spatial dependence on strong-field processes has rarely been investigated. Presented in this work is a theoretical analysis of this spatial dependence including a proposal for an experimentally observable result of the phenomenon. We begin by outlining the elements of the laser field that will vary as a function of position and show their effects on simple free electron trajectories. We …
A Bayesian Network Approach To Feature Selection In Mass Spectrometry Data, Karl W. Kuschner
A Bayesian Network Approach To Feature Selection In Mass Spectrometry Data, Karl W. Kuschner
Dissertations, Theses, and Masters Projects
One of the key goals of current cancer research is the identification of biologic molecules that allow non-invasive detection of existing cancers or cancer precursors. One way to begin this process of biomarker discovery is by using time-of-flight mass spectroscopy to identify proteins or other molecules in tissue or serum that correlate to certain cancers. However, there are many difficulties associated with the output of such experiments. The distribution of protein abundances in a population is unknown, the mass spectroscopy measurements have high variability, and high correlations between variables cause problems with popular methods of data mining. to mitigate these …
Dependence-Driven Techniques In System Design, Ningfang Mi
Dependence-Driven Techniques In System Design, Ningfang Mi
Dissertations, Theses, and Masters Projects
Burstiness in workloads is often found in multi-tier architectures, storage systems, and communication networks. This feature is extremely important in system design because it can significantly degrade system performance and availability. This dissertation focuses on how to use knowledge of burstiness to develop new techniques and tools for performance prediction, scheduling, and resource allocation under bursty workload conditions.;For multi-tier enterprise systems, burstiness in the service times is catastrophic for performance. Via detailed experimentation, we identify the cause of performance degradation on the persistent bottleneck switch among various servers. This results in an unstable behavior that cannot be captured by existing …
Chaotic Scattering In An Open Vase-Shaped Cavity: Topological, Numerical, And Experimental Results, Jaison Allen Novick
Chaotic Scattering In An Open Vase-Shaped Cavity: Topological, Numerical, And Experimental Results, Jaison Allen Novick
Dissertations, Theses, and Masters Projects
We present a study of trajectories in a two-dimensional, open, vase-shaped cavity in the absence of forces The classical trajectories freely propagate between elastic collisions. Bound trajectories, regular scattering trajectories, and chaotic scattering trajectories are present in the vase. Most importantly, we find that classical trajectories passing through the vase's mouth escape without return. In our simulations, we propagate bursts of trajectories from point sources located along the vase walls. We record the time for escaping trajectories to pass through the vase's neck. Constructing a plot of escape time versus the initial launch angle for the chaotic trajectories reveals a …
A Privacy Preserving Framework For Cyber-Physical Systems And Its Integration In Real World Applications, Haodong Wang
A Privacy Preserving Framework For Cyber-Physical Systems And Its Integration In Real World Applications, Haodong Wang
Dissertations, Theses, and Masters Projects
A cyber-physical system (CPS) comprises of a network of processing and communication capable sensors and actuators that are pervasively embedded in the physical world. These intelligent computing elements achieve the tight combination and coordination between the logic processing and physical resources. It is envisioned that CPS will have great economic and societal impact, and alter the qualify of life like what Internet has done. This dissertation focuses on the privacy issues in current and future CPS applications. as thousands of the intelligent devices are deeply embedded in human societies, the system operations may potentially disclose the sensitive information if no …
Malware Detection And Analysis Via Layered Annotative Execution, Heng Yin
Malware Detection And Analysis Via Layered Annotative Execution, Heng Yin
Dissertations, Theses, and Masters Projects
Malicious software (i.e., malware) has become a severe threat to interconnected computer systems for decades and has caused billions of dollars damages each year. A large volume of new malware samples are discovered daily. Even worse, malware is rapidly evolving to be more sophisticated and evasive to strike against current malware analysis and defense systems. This dissertation takes a root-cause oriented approach to the problem of automatic malware detection and analysis. In this approach, we aim to capture the intrinsic natures of malicious behaviors, rather than the external symptoms of existing attacks. We propose a new architecture for binary code …
Egg Capsule Hatching Success In Rapana Venosa And Urosalpinx Cinerea In Relation To Temperature And Salinity, Stephanie M. Gera
Egg Capsule Hatching Success In Rapana Venosa And Urosalpinx Cinerea In Relation To Temperature And Salinity, Stephanie M. Gera
Dissertations, Theses, and Masters Projects
The maintenance of a population within the geographic range is influenced by the physical and environmental conditions under which breeding occurs. It is hypothesized that environmental conditions under which egg capsules are successfully hatched will influence the range of potential habitat of the invasive veined rapa whelk, Rapana venosa, and the native Atlantic oyster drill, Urosalpinx cinerea, in the Chesapeake Bay. This study examines the environmental conditions of temperature, salinity, and the time of deposition of egg capsules within the reproductive period (here quantified as cumulative number of day degrees at egg capsule deposition). The range of R. venosa and …
Hydrography And Phytoplankton Distribution In The Amundsen And Ross Seas, Glaucia M. Fragoso
Hydrography And Phytoplankton Distribution In The Amundsen And Ross Seas, Glaucia M. Fragoso
Dissertations, Theses, and Masters Projects
The phytoplankton of the Ross Sea have been intensively studied during the last decade, as opposed to the Amundsen Sea, where virtually nothing is known about phytoplankton taxonomy and distribution. Blooms in the Ross Sea are usually composed of diatoms and the prymnesiophyte Phaeocystis antarctica; diatoms are often dominant in strongly stratified waters during the summer, whereas P. antarctica usually dominates in less stratified waters in the south-central polynya during spring. This study focused on understanding the environmental variables that influence the spatial patterns of phytoplankton assemblages during late summer and early fall, 2007, and late spring and early summer, …
Nutrient Loading And System Response In The Coastal Lagoons Of The Delmarva, Juliette Christina Poleto Giordano
Nutrient Loading And System Response In The Coastal Lagoons Of The Delmarva, Juliette Christina Poleto Giordano
Dissertations, Theses, and Masters Projects
No abstract provided.
Toxicology Of Decabromodiphenyl Ether In Avian Embryos: Disposition Of The Flame Retardant Bde-209 In Yolk-Injected Chicken Embryos (Gallus Gallus), Samantha D. Sifleet
Toxicology Of Decabromodiphenyl Ether In Avian Embryos: Disposition Of The Flame Retardant Bde-209 In Yolk-Injected Chicken Embryos (Gallus Gallus), Samantha D. Sifleet
Dissertations, Theses, and Masters Projects
Polybrominated diphenyl ethers (PBDEs) are flame retardant chemicals of toxicological concern present in humans, wildlife, and the environment. Deca-BDE is the highest production product due to historical use patterns and recent regulatory limitations on the other two commercial formulations (Penta-BDE and Octa-BDE) in the U.S and Europe. The EU banned Deca-BDE starting July 1, 2008. However, it remains in usage in North America and elsewhere in the world. BDE-209 is the dominant congener in all Deca- BDE commercial products. BDE-209 has been reported to under go metabolic debromination to lesser brominated and more toxic and bioaccumulative congeners. However, insufficient data …