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Articles 61 - 90 of 114
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Wild Yankees: Settlement, Conflict, And Localism Along Pennsylvania's Northeast Frontier, 1760-1820, Paul Benjamin Moyer
Wild Yankees: Settlement, Conflict, And Localism Along Pennsylvania's Northeast Frontier, 1760-1820, Paul Benjamin Moyer
Dissertations, Theses, and Masters Projects
Pennsylvania's northeast frontier---a region embraced by the upper reaches of the Delaware and Susquehanna Rivers---was the scene of a bitter and, at times, bloody backwoods dispute. Here Yankees (settlers and speculators holding deeds from Connecticut land companies) fought Pennamites (settlers and landlords who claimed land under Pennsylvania) for land and authority. This contest began in the 1760s and lasted till the first decade of the nineteenth century and, for a time, pitted Connecticut against Pennsylvania in a bitter jurisdictional conflict. This study focuses on the dispute after the revolutionary war when the federal government awarded the contested territory to Pennsylvania …
Experimental And Computational Techniques In Carbon-13 Nmr, Samuel John Varner
Experimental And Computational Techniques In Carbon-13 Nmr, Samuel John Varner
Dissertations, Theses, and Masters Projects
An efficient method for calculating NMR lineshapes from anisotropic second rank tensor interactions is presented. The algorithm produces lineshapes from asymmetric tensors by summing those from symmetric tensors. This approach significantly reduces the calculation time, greatly facilitating iterative nonlinear least squares fitting of experimental spectra. This algorithm has been modified to produce partially relaxed lineshapes and spectra of partially ordered samples.;Calculations for rapidly spinning samples show that spin-lattice relaxation time ( T1Z ) anisotropy varies with the angle between the spinning axis and the external field. When the rate of molecular motion is in the extreme narrowing limit, measurement of …
The Thermographic Nondestructive Evaluation Of Iron Aluminide Green Sheet, Michael L. Watkins
The Thermographic Nondestructive Evaluation Of Iron Aluminide Green Sheet, Michael L. Watkins
Dissertations, Theses, and Masters Projects
The recent development of manufacturing techniques for the fabrication of thin iron aluminide sheet requires advanced quantitative methods for on-line inspection. An understanding of the mechanisms responsible for flaws and the development of appropriate flaw detection methods are key elements in an effective quality management system. The first step in the fabrication of thin FeAl alloy sheet is the formation of a green sheet by cold rolling FeAl powder mixed with organic binding agents. The green sheet composite has a bulk density, which is typically less than about 3.6 g/cc. The finished sheet, with a density of about 6.1 g/cc, …
Studies In Microwave And Rf Capacitively Coupled Excimer Lamp, Joseph Divine Ametepe
Studies In Microwave And Rf Capacitively Coupled Excimer Lamp, Joseph Divine Ametepe
Dissertations, Theses, and Masters Projects
A lamp that emits strongly in the 180--200 nm region is desirable because of the response of organic materials in this wavelength range. Therefore there is the demand for high-powered, efficient, and low-cost UV and VUV sources.;The purpose of this work is to construct and study two novel (low-cost) UV sources and to understand the (1) emission (180--200 nm) characteristics, (2) electron energy and (3) temperature distribution in the plasmas generated by these two novel excimer lamps.;We designed, constructed and studied (1) a probe-coupled 2.45 GHz microwave arrangement to drive Xe and KrI excimer lamps and (2) a 13.45 GHz …
Accurate Visualization Of Distributed System Execution, Dennis Lee Edwards
Accurate Visualization Of Distributed System Execution, Dennis Lee Edwards
Dissertations, Theses, and Masters Projects
The concurrent execution of processes in a distributed system makes the interactions between them difficult to understand. A clear image of the execution sequence that occurs as well as possible alternative scenarios is paramount to providing the software engineer the understanding needed to create reliable software.;In this thesis, we examine several representation methods of presenting a pictorial view of the execution of a distributed system and evaluate each in terms of three criteria. First, only those relationships that are created during the execution can and must be presented. Second, the presentation must be such that a reasonable amount of information …
Decay Search For The Supersymmetric R(0) (Gluon Gluino) Hadron Via The Channel R(0) Going To Positive Pion Negative Pion Photino, Kevin Michael Hern
Decay Search For The Supersymmetric R(0) (Gluon Gluino) Hadron Via The Channel R(0) Going To Positive Pion Negative Pion Photino, Kevin Michael Hern
Dissertations, Theses, and Masters Projects
There has been recent theoretical interest in supersymmetry breaking scenarios in which the gauginos are light compared to the squarks. One prediction of these light gluino models is the existence of the R 0 hadron (gg?£). Brookhaven National Laboratory AGS Experiment 935 (E935) searched for light gluinos through the appearance of pi+pi- pairs with invariant mass Mpipi > 545 MeV/c2 in a high flux neutral beam. The search has yielded one candidate event. This event is consistent with the anticipated background of 1.4 events due to interactions of neutrons in the beam with the residual gas in the evacuated decay region. …
Characterization Of The Physical Properties Of Iron Polyimide Nanocomposites, Russell A. Wincheski
Characterization Of The Physical Properties Of Iron Polyimide Nanocomposites, Russell A. Wincheski
Dissertations, Theses, and Masters Projects
The discovery of tunneling magneto-resistance has led to a great deal of interest in the study of ferromagnet-insulator-ferromagnet (FIF) systems due to potential sensor and magnetic storage applications. An analysis of the band structure of the 3d ferromagnets shows that the conduction electrons become spin polarized by the molecular field. The transmission coefficient of these electrons across a tunneling gap therefore depends upon the relative alignment of the molecular field between the two ferromagnets.;In this work the manufacture of such tunneling gaps through compression molding of powdered ferromagnetic iron with a high performance polyimide has been studied for the first …
Dynamic Load Balancing Via Thread Migration, David Cronk
Dynamic Load Balancing Via Thread Migration, David Cronk
Dissertations, Theses, and Masters Projects
Light-weight threads are becoming increasingly useful for parallel processing. This is particularly true for threads running in a distributed memory environment. Light-weight threads can be used to support latency hiding techniques, communication and computation overlap, and functional parallelism. Additionally, dynamic migration of light-weight threads supports both data locality and load balancing. Designing a thread migration mechanism presents some very unique and interesting challenges. One such challenge is maintaining communication between mobile threads. A potentially more difficult challenge involves maintaining the correctness of pointers within mobile threads. Since traditional pointers have no concept of address space, moving threads from processor to …
Causal Distributed Assert Statements, Sharon J. Simmons
Causal Distributed Assert Statements, Sharon J. Simmons
Dissertations, Theses, and Masters Projects
Monitoring a program's execution is fundamental to the debugging, testing and maintenance phases of program development. This research addresses the issue of monitoring the execution of a distributed program. In particular, we are concerned with efficient techniques for evaluating global state predicates for distributed programs. The global state of a distributed program is not well-defined, making the monitoring task complex compared to that of a sequential programs. Processes of a distributed program execute concurrently, and the events of the program cannot be totally ordered. Each process has its own local memory, and the local memories are physically separate.;Despite the difficulties …
Electroproduction Of Omega (783) Mesons Using Clas At Jefferson Lab, Alan Clayton Coleman
Electroproduction Of Omega (783) Mesons Using Clas At Jefferson Lab, Alan Clayton Coleman
Dissertations, Theses, and Masters Projects
Electroproduction of omega(783) mesons from a proton target has been measured in a search for so called "missing baryon resonances". A 4.0 GeV electron beam was used. The scattered electrons were measured in coincidence with the recoiling proton and the positive pion from the omega decay. Missing mass techniques were applied to identify the omega in the final state, and to reduce the rho(770) contribution. The data show the omega very clearly on a smooth background originating predominantly from three-pion phase space. Yields have been extracted, and the W and t dependencies determined. The t dependence is mostly monotonic for …
Eying Italians: Race, Romance, And Reality In American Perception, 1880--1910, Joseph Peter Cosco
Eying Italians: Race, Romance, And Reality In American Perception, 1880--1910, Joseph Peter Cosco
Dissertations, Theses, and Masters Projects
This dissertation explores how American representations of Italians and Italian Americans engaged, reflected and helped shape the United States' developing concepts of immigration, ethnicity, race, and national identity from 1880 to 1910, when masses of Italian and other "new immigrants" rigorously tested the country's attitudes and powers of assimilation. In a larger sense, the research examines how the process of constructing the modern Italian/Italian American was part of the process of America constructing for itself a modern national identity for a new century.;The dissertation looks at a variety of "texts," including journalism, travel literature, autobiography, fiction, and photographs and illustrations …
Thermoelastic And Photoelastic Full-Field Stress Measurement, Deonna Faye Woolard
Thermoelastic And Photoelastic Full-Field Stress Measurement, Deonna Faye Woolard
Dissertations, Theses, and Masters Projects
Photoelasticity is an optical technique that measures the difference of the principal stresses plus the principal stress direction. A complementary technique is thermoelasticity which measures the sum of the principal stresses. Combining these two full-field, non-contact nondestructive evaluation techniques allows the individual stress components to be measured. One of the main difficulties in merging these two measurement systems is in identifying an appropriate surface coating. Thermoelasticity demands a highly emissive surface, while photoelasticity requires a thick, stress-birefringent, transparent coating with a retro-reflective backing. Two coatings have been identified that can be used for combined thermoelastic and photoelastic stress measurements: PMMA …
Diet Composition And Feeding Habits Of Large Striped Bass, Morone Saxatilis, In Chesapeake Bay, John F. Walter
Diet Composition And Feeding Habits Of Large Striped Bass, Morone Saxatilis, In Chesapeake Bay, John F. Walter
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.
Carbon Production And Growth Physiology Of Heterotrophic Bacteria In A Subtropical Coral Reef Ecosystem, Peter Dylan Countway
Carbon Production And Growth Physiology Of Heterotrophic Bacteria In A Subtropical Coral Reef Ecosystem, Peter Dylan Countway
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.
Limitation Of Bacterial Growth By Dissolved Organic Matter And Iron In The Southern Ocean, Matthew J. Church
Limitation Of Bacterial Growth By Dissolved Organic Matter And Iron In The Southern Ocean, Matthew J. Church
Dissertations, Theses, and Masters Projects
No abstract provided.
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.
A Content Analysis Of State Legislative Responses To Educator Assault, Jamie Heider Arkin
A Content Analysis Of State Legislative Responses To Educator Assault, Jamie Heider Arkin
Dissertations, Theses, and Masters Projects
Educators increasingly find themselves having to rely on laws for protection from threats or attacks, and educator assault laws reflect the diverse and unique needs of the individual states. This study sought to determine if the state legislatures in each of the 50 states have created legislation punishing educator assault and to compare, contrast, and analyze any existing statutes by using content analysis methodology. Currently, 37 states possess educator assault legislation. Specific features within each law were examined: its protected recipient, the prohibited action, identification of the aggressor, any limiting or qualifying statements, and the stated penalties. Several trends emerged; …
Distribution, Swimming Physiology, And Swimming Mechanics Of Brief Squid Lolliguncula Brevis, Ian K. Bartol
Distribution, Swimming Physiology, And Swimming Mechanics Of Brief Squid Lolliguncula Brevis, Ian K. Bartol
Dissertations, Theses, and Masters Projects
Squids are thought to have physiological and locomotive deficiencies that put them at a competitive disadvantage to fishes and exclude them from inshore, highly variable environments that are rich in nektonic fauna. However, brief squid Lolliguncula brevis may be a notable exception. Trawl surveys revealed that L. brevis, particularly juveniles <6 cm dorsal mantle length (DML), are abundant in the Chesapeake Bay, especially when salinity and water temperature are high, and tolerate a wide range of physical conditions relative to other cephalopods. L. brevis is also different from other cephalopods examined previously because its pattern of oxygen consumption as a function of velocity was found to be parabolic and thus similar to aerial flight, and its swimming costs were competitive with ecologically equivalent fishes. Power-speed curves derived from video footage of swimming squid and hydrodynamic force calculations also were parabolic in shape, with high costs both at low and high speeds because of power requirements for lift generation and overcoming drag, respectively. L. brevis employed various behaviors to increase swimming efficiency and compensate for negative buoyancy, such as swimming in various orientations (e.g., arms-first and tail-first), altering angles of attack of the mantle, arms, and funnel, and using fin activity. Fin motion, which could not be characterized exclusively as drag- or lift-based propulsion, was used over 50--95% of the sustained speed range and provided as much as 78% of the vertical and 55% of the horizontal thrust. Small squid (<3.0 cm DML) used different swimming strategies than larger squid possibly to maximize the benefits of toroidal induction, and aerobic efficiency curves indicated that squid 3--5 cm. DML are most efficient. Brief squid also may take advantage of unsteady phenomena, such as attached vortices, for added lift and thrust. Furthermore, an electromyographic study revealed that L. brevis uses different circular muscle layers for various speeds and like fish has muscular "gears", suggesting that there is specialization and efficient use of locomotive muscle in some cephalopods. Therefore, the presumption that squids are inescapably constrained by a second-rate propulsive system and physiological deficiencies is not applicable to L. brevis.
Morphological, Electrophysiological And Behavioral Investigation Of Visual Acuity Of The Juvenile Loggerhead Sea Turtle (Caretta Caretta), Soraya M. Bartol
Morphological, Electrophysiological And Behavioral Investigation Of Visual Acuity Of The Juvenile Loggerhead Sea Turtle (Caretta Caretta), Soraya M. Bartol
Dissertations, Theses, and Masters Projects
A majority of the research on sea turtle vision focuses on the turtle's ability to perceive shapes, colors and brightness cues on land. However, aerial vision is a minor component of the visual ability of sea turtles, potentially used only when surfacing to breathe, while basking, and during female reproductive activities. For my doctoral dissertation, I examined the aquatic visual acuity of juvenile loggerhead sea turtles (Caretta caretta) by investigating the morphology of the eye, the electrophysiology of response to stimuli, and the behavior to specific stimuli. For the morphological experiments, eyes were obtained from loggerheads, euthanized due to injury, …
Fine-Scale Strata Formation In Biologically And Physically Dominated Estuarine Systems Within The Lower Chesapeake And York River Subestuary, Timothy M. Dellapenna
Fine-Scale Strata Formation In Biologically And Physically Dominated Estuarine Systems Within The Lower Chesapeake And York River Subestuary, Timothy M. Dellapenna
Dissertations, Theses, and Masters Projects
To investigate the relationship between biological and physical mixing in forming strata, the lower mainstem of Chesapeake Bay has been contrasted with the York River Subestuary. By using radioisotope profiles from sediment cores, comparisons are made in terms of depth and rate of sediment mixing, deposition and accretion. Within the lower Chesapeake Bay two sites were selected as biologically dominated, both are located within the bay stem plains and are characterized by muddy sand and an abundance of large, deep-dwelling organisms. X-radiographs indicate complete biological reworking of sediments. 210Pb profiles reveal low sediment accretion rates within the mainstem sites ( …
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.
Nitrate Reduction At The Groundwater - Salt Marsh Interface, Craig -1967 Tobias
Nitrate Reduction At The Groundwater - Salt Marsh Interface, Craig -1967 Tobias
Dissertations, Theses, and Masters Projects
The influence of groundwater discharge on the hydrology and biogeochemical cycling of nitrogen in a fringing intertidal wetland was studied by characterizing groundwater discharge, determining N-cycling rates in cores, and examining nitrate reduction in situ using 15N enrichment and natural gradient tracer techniques. Groundwater discharge was estimated by three independent methods: Darcy's Law, a water/salt mass balance, and a subsurface tracer test. Seasonal patterns of discharge predicted by Darcy's Law and the mass balance were similar. Discharge maxima and minima occurred in April and September, respectively. The water/salt mass balance provided the more reasonable estimate of groundwater flux at high …
Artificial Societies: A Computational Model Of Disease Transmission, Nathan T. Moore
Artificial Societies: A Computational Model Of Disease Transmission, Nathan T. Moore
Dissertations, Theses, and Masters Projects
No abstract provided.
Artificial Societies: A Computational Approach To Studying Combat, Rachel J. Moore
Artificial Societies: A Computational Approach To Studying Combat, Rachel J. Moore
Dissertations, Theses, and Masters Projects
No abstract provided.
The Relationship Among Registered Nurse's Years Of Experience, Credentials, Work Location, Completed Non-Required Continuing Education Hours, Moral Development And Conceptual Level, Agatha Custodio Dado Parks
The Relationship Among Registered Nurse's Years Of Experience, Credentials, Work Location, Completed Non-Required Continuing Education Hours, Moral Development And Conceptual Level, Agatha Custodio Dado Parks
Dissertations, Theses, and Masters Projects
Limited research has been done regarding the relationship among registered nurses years of experience, credentials, work location, completed non-required continuing education hours, moral development, and conceptual level. This study's theoretical framework is based on the cognitive-developmental theory domains of moral and conceptual development. A descriptive and correlational research design was used to discover the relationship between variables. One hundred registered nurses were selected from a hospital in southeastern Virginia. Participants completed a general questionnaire, Defining Issues Test-2 and the Paragraph Completion Method. Findings resulted in failing to reject the null hypotheses. There was no statistically significant correlation among the variables. …
"C" Is For Cookie, Culture, And Capitalism: The Muppet Phenomenon In The United States, Nicole B. Cloeren
"C" Is For Cookie, Culture, And Capitalism: The Muppet Phenomenon In The United States, Nicole B. Cloeren
Dissertations, Theses, and Masters Projects
No abstract provided.
Stormy Weather: Lena Horne, Dorothy Dandridge And The Cultural Politics Of Stardom, Amy L. Howard
Stormy Weather: Lena Horne, Dorothy Dandridge And The Cultural Politics Of Stardom, Amy L. Howard
Dissertations, Theses, and Masters Projects
No abstract provided.
Luxury Consumption In 1815 Fredericksburg, Virginia: Gender, Race, And The Personal Property Tax, Shannon Lynn Hughes
Luxury Consumption In 1815 Fredericksburg, Virginia: Gender, Race, And The Personal Property Tax, Shannon Lynn Hughes
Dissertations, Theses, and Masters Projects
No abstract provided.