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Experimental Framework For The Position Control Of Magnetic Microfibers, Sriram Ravindren Jul 2008

Experimental Framework For The Position Control Of Magnetic Microfibers, Sriram Ravindren

All Theses

Magnetic microfibers have been developed in recent years with potential applications to a large number of fields, from MEMS to microfluidics to bio-chemical analyses. Magnetic microfibers based on polymer material like polypropylene and cellulose has been developed at Clemson University that are hollow cylindrical filaments internally coated with superparamagnetic nanoparticles. This internal coating provides the fiber with magnetic properties that allow them to be externally controlled using magnetic fields from a distance. These fibers can align with the external magnetic fields under constraints imposed by elastic properties and boundary conditions. Current work in this field is primarily focused on the …

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Design Process Modeling: Towards An Ontology Of Engineering Design Activities, Pavan Kumar Jul 2008

Design Process Modeling: Towards An Ontology Of Engineering Design Activities, Pavan Kumar

All Theses

An ontology of engineering design activities, called the Design Activity Ontology (DAO), is developed in this research. The DAO models 82 information flows and 25 design activities. These activities cover phases of the design process from conceptual phase through detail design phase. The ontology provides a formalized and structured vocabulary of design activities for consistency and exchange of design process models. The DAO enables design processes to be modeled, analyzed and optimized. The DAO is constructed using information flows identified in current design literature, commonly accepted engineering design textbooks, and an existing activity ontology. Specifically, the DAO is an extension …

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Real-Time Midi Performance Evaluation For Beginning Piano Students, David Duvall Jul 2008

Real-Time Midi Performance Evaluation For Beginning Piano Students, David Duvall

All Theses

MIDI is a standard digital protocol for the communication of musical events. In this paper, we examine the construction of a complex system to validate musical performance characteristics without compromising musical interpretation through the use and evaluation of MIDI messages. Beginning music students often have a difficult time translating written, musical characteristics to the correlating sound that they imply. Even though a teacher can effectively help a student through this learning process, the process can typically be slow, as evaluation of musical performances happens only once a week during a thirty minute lesson. Prior research has shown that a model, …

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Remchlor Model Of Tritium Transport At The Made Site, Shelly Tyre Jul 2008

Remchlor Model Of Tritium Transport At The Made Site, Shelly Tyre

All Theses

Groundwater transport models are commonly used at sites with groundwater contamination. Models are used to study the extent of the contamination and the possible risks it poses. Contaminant transport models use properties of the aquifer and the solute to simulate how the solute moves through the aquifer. Screening level models are often used as a first modeling approach at sites to get an idea of the general trends of contaminant transport. They offer an efficient approach to modeling, usually requiring fewer input parameters than other models.
This study uses a screening level model to describe tritium transport for the second …

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Stability Analysis And Decentralized Control Of Coupled Oscillators With Feedback Delays, Saurabh Keni Jul 2008

Stability Analysis And Decentralized Control Of Coupled Oscillators With Feedback Delays, Saurabh Keni

All Theses

Most dynamic systems do not react instantaneously to actuation signals. The temporal evolution of some others is based on retarded communications or depends on information from the past. In such cases, the mathematical models used to describe these systems must include information about the past dynamics of the states. These models are often referred to as delay or retarded systems. Delays could channel energy in and out of a system at incorrect time intervals producing instabilities and rendering controllers' performance ineffective.
The purpose of this research is two folds. The first investigates the effect of inherent system delays on the …

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Estimation Of Vehicle Mass And Road Grade, Tejas Ghotikar Jul 2008

Estimation Of Vehicle Mass And Road Grade, Tejas Ghotikar

All Theses

This thesis describes development of a real-time-implementable algorithm for simultaneous estimation of a heavy vehicle's mass and time-varying road grade and its verification with experimental data. Accurate estimate of a heavy vehicle's mass is critical in several vehicle control functions such as in transmission and stability control. The goal is to utilize the standard signals on a vehicle in a model-based estimation strategy, as opposed to a more costly sensor-based approach. The challenge is that unknown road grade complicates model-based estimation of vehicle mass and therefore the time-varying grade should be estimated simultaneously. In addition an estimate of road grade …

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Fpga Acceleration Of A Cortical And A Matched Filter-Based Algorithm, Kenneth Rice Jul 2008

Fpga Acceleration Of A Cortical And A Matched Filter-Based Algorithm, Kenneth Rice

All Theses

Digital image processing is a widely used and diverse field. It is used in a broad array of areas such as tracking and detection, object avoidance, computer vision, and numerous other applications. For many image processing tasks, the computations can become time consuming. Therefore, a means for accelerating the computations would be beneficial. Using that as motivation, this thesis examines the acceleration of two distinctly different image processing applications. The first image processing application examined is a recent neocortex inspired cognitive model geared towards pattern recognition as seen in the visual cortex. For this model, both software and reconfigurable logic …

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Water Levels Effects On Overall Customer Satisfaction:, Crayton Pruitt Jul 2008

Water Levels Effects On Overall Customer Satisfaction:, Crayton Pruitt

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Abstract The combination of hydroelectric power generation and the amount of precipitation results in fluctuating water levels on the United States Army Corps of Engineers: Lake Hartwell. Beginning in 2002 and continuing to the end of survey year 2004, water levels ranged from approximately ten feet below full pool to within half a foot under full pool. These fluctuations created difficulty for adjacent landowners to access sufficient water depths for recreational needs. The problems were magnified by a common perception that neighboring lakes', Lake Keowee and Lake Thurmond, water levels had not dropped as dramatically. This study examined the effects …

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Topology And Free-Size Optimization With Multiple Loading Conditions For Light Weight Design Of Die Cast Automotive Backrest Frame, Sreeram Polavarapu Jul 2008

Topology And Free-Size Optimization With Multiple Loading Conditions For Light Weight Design Of Die Cast Automotive Backrest Frame, Sreeram Polavarapu

All Theses

Automotive seats provide comfort and safety to the occupant travelling in the vehicle. An optimized seat design should be aesthetically pleasing, lightweight and meet the safety requirements. An automotive seat with occupant is subjected to various kinds of forces in the event of crash and should be designed for strength and stiffness as measured by stress and strain, and deflection. In this work, finite element analysis, together with topology and free-size optimization is used to design a lightweight die cast automotive front seat backrest frame when subjected to loads prescribed by ECE R17 European government regulations and additional loads which …

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Autonomous Navigation And Mapping Using Monocular Low-Resolution Grayscale Vision, Vidya Murali Jul 2008

Autonomous Navigation And Mapping Using Monocular Low-Resolution Grayscale Vision, Vidya Murali

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Vision has been a powerful tool for navigation of intelligent and man-made systems ever since the cybernetics revolution in the 1970s. There have been two basic approaches to the navigation of computer controlled systems: The self-contained bottom-up development of sensorimotor abilities, namely perception and mobility, and the top-down approach, namely artificial intelligence, reasoning and knowledge based methods. The three-fold goal of autonomous exploration, mapping and localization of a mobile robot however, needs to be developed within a single framework. An algorithm is proposed to answer the challenges of autonomous corridor navigation and mapping by a mobile robot equipped with a …

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Developing A Coherent Cyberinfrastructure From Local Campus To National Facilities: Challenges And Strategies, Amy Apon, Patrick Dreher, Vijay Agarwala, Stan Ahalt, Guy Almes, Sue Fratkin, Thomas Hauser, Jan Odegard, Jim Pepin, Craig Stewart Jul 2008

Developing A Coherent Cyberinfrastructure From Local Campus To National Facilities: Challenges And Strategies, Amy Apon, Patrick Dreher, Vijay Agarwala, Stan Ahalt, Guy Almes, Sue Fratkin, Thomas Hauser, Jan Odegard, Jim Pepin, Craig Stewart

Publications

A fundamental goal of cyberinfrastructure (CI) is the integration of computing hardware, software, and network technology, along with data, information management, and human resources to advance scholarship and research. Such integration creates opportunities for researchers, educators, and learners to share ideas, expertise, tools, and facilities in new and powerful ways that cannot be realized if each of these components is applied independently. Bridging the gap between the reality of CI today and its potential in the immediate future is critical to building a balanced CI ecosystem that can support future scholarship and research. This report summarizes the observations and recommendations …

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Clemson A&M College Class Of 1939 Reunion Program 2008, Clemson University Jun 2008

Clemson A&M College Class Of 1939 Reunion Program 2008, Clemson University

Reunion Programs

No abstract provided.

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The Square Threshold Problem In Number Fields, Matt Lafferty May 2008

The Square Threshold Problem In Number Fields, Matt Lafferty

All Theses

Let K be a degree n extension of Q, and let O_K be the ring of algebraic integers in K. Let x >= 2. Suppose we were to generate an ideal sequence by choosing ideals with norm at most x from O_K, independently and with uniform probability. How long would our sequence of ideals need to be before we obtain a subsequence whose terms have a product that is a square ideal in O_K? We show that the answer is about exp((2\ln(x)\ln\ln(x))^(1/2)).

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Evaluation Of A Pilot-Scale Constructed Wetland Treatment System For Ash Basin Water, Lane Dorman May 2008

Evaluation Of A Pilot-Scale Constructed Wetland Treatment System For Ash Basin Water, Lane Dorman

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This investigation examined the feasibility of using surface-flow constructed wetland treatment systems (CWTSs) to decrease the concentration and bioavailability of targeted constituents of concern (COC) in ash basin water. Ash basin water results from hydraulic transport (sluicing) of coal ash produced during thermoelectric power production. During the sluicing process, potentially toxic trace elements contained within coal ash may be transferred to the aqueous phase and subsequently introduced to aquatic receiving systems. COC in ash basin water were identified by a risk quotient method in order to determine biogeochemical conditions needed within wetland reactors for reducing the aqueous concentration and bioavailability …

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Clemson Commencement Program, May 2008, Clemson University May 2008

Clemson Commencement Program, May 2008, Clemson University

Clemson Commencement Programs

No abstract provided.

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Hypoelastic Modeling Of Reinforced Concrete Walls, Mohsen A. Shayanfar, Amir Safiey May 2008

Hypoelastic Modeling Of Reinforced Concrete Walls, Mohsen A. Shayanfar, Amir Safiey

Publications

This paper presents a new hypoelasticity model which was implemented in a nonlinear finite element formulation to analyze reinforced concrete (RC) structures. The model includes a new hypoelasticity constitutive relationship utilizing the rotation of material axis through successive iterations. The model can account for high nonlinearity of the stress-strain behavior of the concrete in the pre-peak regime, the softening behavior of the concrete in the post-peak regime and the irrecoverable volume dilatation at high levels of compressive load. This research introduces the modified version of the common application orthotropic stress-strain relation developed by Darwin and Pecknold. It is endeavored not …

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Three Essays On Environmental Economics And International Trade, Patrick Mclaughlin May 2008

Three Essays On Environmental Economics And International Trade, Patrick Mclaughlin

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ABSTRACT This dissertation addresses the broad topic of appropriate metrics, proxies, and estimation methods in environmental economics and international trade research, presented as three separate studies. The first, entitled, 'Something in the Water? Testing for Groundwater Quality Information in the Housing Market,' examines how informed real estate markets are with respect to groundwater quality by using a couple of different proxies for groundwater quality in a hedonic framework. This research topic has potentially suffered from imperfect proxies and incomplete information, which I test. In the second, entitled, 'Do Economic Integration Agreements Actually Work? Issues in Understanding the Causes and Consequences …

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Structure And Dynamics Of Poly (Para-Phenyleneethynylene)S In Solutions And Thin Films, Yunfei Jiang May 2008

Structure And Dynamics Of Poly (Para-Phenyleneethynylene)S In Solutions And Thin Films, Yunfei Jiang

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This research focuses on the structure and dynamics of a family of rigid polymers, poly(para-phenyleneethynylene)s (PPEs) in solutions and thin films using small angle neutron scattering, neutron spin echo, nuclear magnetic resonance, X-ray scattering, atomic force microscopy and fluorescence spectroscopy. The effects of the solvent and the side chain on the molecular conformation and the association of PPEs have been investigated.
In dilute solutions, the phase diagram of dinonyl PPE in toluene and cyclohexane exhibits three distinct phases. At higher temperatures, PPEs form molecular solutions with extended conformations in toluene and worm-like chains in cyclohexane. With decreasing temperatures, PPEs associate …

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Anaerobic Biodegradation Of Ethylene Dibromide And 1,2-Dichloroethane In The Presence Of Fuel Hydrocarbons, James Henderson May 2008

Anaerobic Biodegradation Of Ethylene Dibromide And 1,2-Dichloroethane In The Presence Of Fuel Hydrocarbons, James Henderson

All Dissertations

Field evidence from underground storage tank (UST) sites where leaded gasoline leaked indicates the lead scavengers 1,2-dibromoethane (ethylene dibromide, or EDB) and 1,2-dichloroethane (1,2-DCA) may be present in groundwater at levels that pose unacceptable risk. These compounds are seldom tested for at UST sites. Although dehalogenation of EDB and 1,2-DCA is known to occur, the effect of fuel hydrocarbons on their biodegradability under anaerobic conditions is poorly understood. Microcosms (2 L glass bottles) were prepared with soil and groundwater from a UST site in Clemson, South Carolina, using samples collected from the source (containing residual fuel) and less contaminated downgradient …

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Study Of Electrospinning Of Property-Modulated Biomedical Microfibers, Scott Taylor May 2008

Study Of Electrospinning Of Property-Modulated Biomedical Microfibers, Scott Taylor

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Electrospinning technologies have been of great interest in recent years, due in large part to developments in the field of Bioengineering, including the preparation of novel polymers and advances in tissue engineering, specifically for therapeutic applications. The electrospinning process is, in general, a very benign process that allows the preparation, under mild conditions, of micro- and nano-scale fibers from fiberforming materials, as well as traditionally non-fiber forming materials. This process is of specific interest to the biomedical community because it affords an opportunity to create highly-tailored novel constructs with a multitude of possible uses. Some proposed uses for these materials …

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Perfluorocyclobutyl Aryl Ether Polymers: A Modular Approach To Tailored Emission, Andrew Neilson May 2008

Perfluorocyclobutyl Aryl Ether Polymers: A Modular Approach To Tailored Emission, Andrew Neilson

All Dissertations

Aryl trifluorovinyl ethers (TFVE) are versatile precursors to perfluorocyclobutyl aryl ether (PFCB) polymers. TFVE functionalized chromophores of a variety of colors have been synthesized for copolymerization to form PFCB polymers with tunable emissive properties. TFVE small molecule chromophores containing fluorene, benzothiadiazole, and bisthiophene show superb emissive properties and prove that the TFVE and PFCB structures have no effect on chromophore emission. Copolymerization of these chromophores with commercial TFVE monomers produced high molecular weight, thermally stable, emissive materials. With the use of trifunctional TFVE monomers these materials can be made into optical glasses. PFCB-phenylene vinylenes were prepared by Wittig polymerization and …

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Semifluorinated Polymers Via Cycloaddition And Nucleophilic Addition Reactions Of Aromatic Trifluorovinylethers, Scott Iacono May 2008

Semifluorinated Polymers Via Cycloaddition And Nucleophilic Addition Reactions Of Aromatic Trifluorovinylethers, Scott Iacono

All Dissertations

This dissertation encompasses the synthesis, characterization, and properties of semifluorinated polymers derived from thermal polymerization of aryl trifluorovinyl ether (TFVE) monomers. This work is divided into two parts based on the methodology of thermal polymerization using aryl TFVE monomers. The first part of this work involves the thermal [2 + 2]cyclodimerization of aryl TFVE monomers affording perfluorocyclobutyl (PFCB) aryl ether polymers. Chapter 1 provides an overview of PFCB aryl ether polymers as a next-generation class of high performance fluoropolymers that have been successfully employed for a myriad of technologies. PFCB aryl ether polymers are highly desired because of their high …

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Modeling Of The Effect Of Tool Wear On Cutting Forces In Turning, Yu Long May 2008

Modeling Of The Effect Of Tool Wear On Cutting Forces In Turning, Yu Long

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Machining is the most widely used and efficient material removal process, and tool wear in machining is usually of great interest in order to improve machining efficiency and effectiveness. Cutting tool wear patterns such as the flank and crater wear and the dead metal zone (DMZ) may induce the cutting tool geometry variation in machining. As a result, cutting forces may increase or decrease due to the change of tool effective cutting geometry during machining operations. A quantitative understanding of and the ability to predict cutting forces in relation to tool wear are important to the tool life estimation, chatter …

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Carbon Nanotubes And Nanocomposites For Thermal And Electrical Applications, Wei Wang May 2008

Carbon Nanotubes And Nanocomposites For Thermal And Electrical Applications, Wei Wang

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The known electrical and thermal properties of carbon nanotubes have prompted many predictions on their extraordinary potentials for ultimately performing polymeric nanocomposites. In this dissertation, chemical modification and functionalization of carbon nanotubes have been demonstrated as being effective for high-quality polymeric carbon nanotube composites, especially with our approach of using polymers that are structurally identical or maximally similar to the matrix polymers in the nanotube functionalization. For example, a poly(N-vinyl carbazole) (PVK) copolymer containing pendant hydroxyl groups was synthesized for the functionalization of single-walled carbon nanotubes (SWNTs). The shared solubility of the functionalized nanotube samples with PVK matrix polymer enabled …

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Caps: Concurrent Automatic Programming System, Ken Kennedy May 2008

Caps: Concurrent Automatic Programming System, Ken Kennedy

All Dissertations

In the past few years, the focus in microprocessors has shifted from increasing speed to creating processors
that contain multiple cores. In order to effectively use the new processors, concurrent specifications
and applications must be developed. Additionally, there are many applications that require the specifications
to be provably correct. CAPS (Concurrent Automatic Programming System) is designed to aid the user in
the creation, execution, and formal verification of concurrent specifications.
The specification language of CAPS (CAPSL) is a very high-level language designed for concurrency
and automatic conversion to a colored Petri net (CP-net). For each statement of the language, there …

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Synthesis And Electrochemical Studies In Microstructured Media, Jamie Norton May 2008

Synthesis And Electrochemical Studies In Microstructured Media, Jamie Norton

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In-situ electrochemical methods involving both oxidative and reductive mediators were employed to modify the oxidation state (doping level) of PEDOT polymers in colloidal PEDOT-coated silica core-shell particles that were prepared as a dispersion encapsulated in a hydrogel matrix. The modifications of the redox states of the PEDOT coating induced a change in the absorbance characteristics. A mediated electron transfer system was employed to ferry charge from the electrodes of the cell to the isolated particles. The mediator diffuses between the electrode surface and the PEDOT-coated particles to accomplish (de)doping. The developed system was a fully self-contained and electrically driven device. …

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Preparation And Characterization Of Macroporous Electrodes For Electrochemical Bioassays, Ashwin Rao May 2008

Preparation And Characterization Of Macroporous Electrodes For Electrochemical Bioassays, Ashwin Rao

All Dissertations

Applications such as point-of-care medical diagnosis and in-the-field biological warfare agent detection require portable bioassays which are less laborious yet cost effective. Conventional sandwich bioassays see limited use for such applications as it involves time consuming steps of reagent treatment and washings, and are restricted to use inside laboratories. We explore new platforms for sandwich bioassays required by such applications. The platform we have developed is based on electrochemical methods of detection. Flow-through three-dimensional electrodes suitable for use in electrochemical sandwich bioassays were fabricated. A composite of superporous agarose and reticulated vitreous carbon (SPA-RVC) material was used for the fabrication …

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School Building Quality And Student Performance In South Carolina High Schools: A Structural Equation Model, Scott Smith May 2008

School Building Quality And Student Performance In South Carolina High Schools: A Structural Equation Model, Scott Smith

All Dissertations

This study attempts to identify conditions of school building quality that relate to the performance of students in public high schools in South Carolina. The amount of data collected in this area is relatively small, and the researcher wishes to add South Carolina to the list of states that are slowly developing a means to assess school condition. The primary research question in the study asks: How does the condition of a school facility affect student performance, as measured by the High School Assessment Program? The results are analyzed using AMOS in lieu of more traditional statistical approaches. AMOS provides …

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Formation Of Active Catalytic Sites In Hydrocarbon Synthesis And Reaction, Nattaporn Lohitharn May 2008

Formation Of Active Catalytic Sites In Hydrocarbon Synthesis And Reaction, Nattaporn Lohitharn

All Dissertations

Acid and metal catalysis are considerably important in the chemical industry especially, for the production of transportation fuels. Since a serious concern on the world environment has infringed on the restriction of aromatics contained in gasoline, the demand for clean high-octane branched alkanes for gasoline upgrading has significantly increased. This process involves acid catalyzed n-butane isomerization in which n-butane is converted to isobutane, a primary feedstock for the production of high-octane species. In addition, due to the unpredictable price and the limited resource of petroleum fuel derived crude oil, the attention has shifted to synthetic liquid fuels derived from other …

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Investigating Risks, Effects, And A Potential Management Strategy For Avian Vacuolar Myelinopathy On Southeastern Reservoirs Using An Eco-Epidemiological Approach, Rebecca Haynie May 2008

Investigating Risks, Effects, And A Potential Management Strategy For Avian Vacuolar Myelinopathy On Southeastern Reservoirs Using An Eco-Epidemiological Approach, Rebecca Haynie

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Avian vacuolar myelinopathy (AVM) is a neurologic disease of unknown etiology that has severely impacted waterbirds and raptors in the Southern United States since it was first diagnosed in 1994. Research studies have suggested that the causative agent is a neurotoxin produced by a previously undescribed Stigonematalan cyanobacterium which grows epiphytically on submerged aquatic vegetation. A suite of experiments were conducted to determine if: (1) triploid Chinese grass carp (Ctenopharyngodon idella) are an appropriate management strategy for AVM; (2) to measure mammalian susceptibility to cyanobacterium exposure; and, (3) to discern population-level impacts to American coots (Fulica americana) and bald eagles …

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