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Pilot In Loop Assessment Of Fault Tolerant Flight Control Schemes In A Motion Flight Simulator, Girish Kumar Sagoo Aug 2008

Pilot In Loop Assessment Of Fault Tolerant Flight Control Schemes In A Motion Flight Simulator, Girish Kumar Sagoo

Graduate Theses, Dissertations, and Problem Reports (ETD)

This research presents the pilot in the loop tests carried out in a Six-Degree of Freedom (6-DOF) motion flight simulator to evaluate failure detection, isolation and identification (FDII) schemes for an advanced F-15 aircraft. The objective behind this study is to leverage the capability of the flight simulator at West Virginia University (WVU) to carry out a performance assessment of neurally augmented control algorithms developed on a Matlab/Simulink RTM platform. The experimental setup features an interface setup of Gen-2 SimulinkRTM schemes with MOTUS Flight Simulator (MFS). The set up is a close substitute to a real flight and thus is …

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Organic Management Of Mexican Bean Beetle (Epilachna Varivestis Mulsant) In Snap Bean (Phaseolus Vulgaris L.), Tiffany L. Fess Aug 2008

Organic Management Of Mexican Bean Beetle (Epilachna Varivestis Mulsant) In Snap Bean (Phaseolus Vulgaris L.), Tiffany L. Fess

Graduate Theses, Dissertations, and Problem Reports (ETD)

Various methods have been suggested to control or deter MBB from attacking bean crops, however conclusive data detailing the effectiveness of control methods and their effects on green bean yield are limited. Two separate experiments were performed to compare MBB management practices in snap bean crops and determine snap bean varieties with natural tolerance to MBB infestations. P. foveolatus in snap bean crops significantly (P<0.05) reduced the larval and adult MBB populations, while increasing the bean yield in optimal growing conditions. The use of row cover and staggering of planting date proved to be unsuccessful (P>0.05) increasing bean yield, however MBB larval, pupal, and adult populations were found to be different (P<0.05) when growing conditions wee optimal. When MBB populations were above the economic threshold (1--1.5 MBB larvae per plant) in the test, tolerance to MBB infestation was not observed (P>0.05) in any of the varieties studied.

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Predictive Modeling Of Freshwater Mussels (Unionidae) In The Appalachians, Alison R. Mynsberge Aug 2008

Predictive Modeling Of Freshwater Mussels (Unionidae) In The Appalachians, Alison R. Mynsberge

Graduate Theses, Dissertations, and Problem Reports (ETD)

Freshwater mussels are in decline, particularly in the Appalachian region of North America. This region contains the world's greatest diversity of freshwater mussels, but many species are now threatened or endangered. Little is known of the basic ecology and distributions of species of freshwater mussels relative to other freshwater organisms. The goal of this study was to use predictive modeling to predict distributions of freshwater mussels in the Appalachians and identify correlated factors using a watershed framework. Models were developed in the upper Mid-Atlantic and Ohio drainage regions using subwatersheds and separately in the Tennessee region using catchments. Models developed …

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Analysis Of Tomato Synthetic Seeds For The Development Of An Optimized Encapsulation System, John E. Porter Aug 2008

Analysis Of Tomato Synthetic Seeds For The Development Of An Optimized Encapsulation System, John E. Porter

Graduate Theses, Dissertations, and Problem Reports (ETD)

In vitro propagules of tomato ( Solanum lycopersicum L.) were used to evaluate the effects of alginate encapsulation and subsequent storage for synthetic seed (synseed) production. Nodal segments were encapsulated in hollow alginate beads with and without supplemental nutrients, auxin (0, 2.5 and 5 muM IBA) and fungicide (0, 50 and 100 muM Daconil 2787). Synseeds were stored for 0, 30 and 90 days at 4+/-1°C in darkness and were given a light treatment (none vs. one week at 25+/-2°C with a 16 hour photoperiod) before sowing in a greenhouse hydroponic system. There was no survival across all treatments of …

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In-Vitro Evaluation Of Dye Leakage Of An Mta Apical Barrier At Varying Setting Times, Mark Daniel Richey Aug 2008

In-Vitro Evaluation Of Dye Leakage Of An Mta Apical Barrier At Varying Setting Times, Mark Daniel Richey

Graduate Theses, Dissertations, and Problem Reports (ETD)

The purpose of this study was to compare the dye leakage of an MTA apical barrier after immediate placement, 1 hour, 4 hours, 24 hours, and 1 week of setting time. One hundred twenty single-rooted extracted teeth were accessed and the apical three millimeters resected. The teeth were instrumented with 0.06 tapered Brasseler EndoSequence series rotary instruments to the apex. The same instrument was then placed in the apical opening and advanced to D16, resulting in an apical opening of 1.36mm. The teeth were randomly assigned to the five test groups, and ten teeth each were placed in positive and …

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Development Of Volunteer-Driven Indices Of Biological Integrity For Wetlands In West Virginia, Walter Emil Veselka Iv Aug 2008

Development Of Volunteer-Driven Indices Of Biological Integrity For Wetlands In West Virginia, Walter Emil Veselka Iv

Graduate Theses, Dissertations, and Problem Reports (ETD)

Wetland indices of biological integrity (IBIs) are used to satisfy the water resources monitoring requirements of the Clean Water Act (CWA). However, debate still exists on what classification systems and taxa to base these IBIs upon. Our cumulative research, representing indices of biological integrity designed for regional HGM subclasses, designated HGM management classes and Cowardin et al. (1979) classes for West Virginia. The indices were derived from metrics calculated from anuran, avian, macroinvertebrate, and vegetation communities; each representing increasing levels of resources associated with gathering the necessary data. For example, avian and anuran data used to derive floodplain wetland IBI …

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Direct Suffix Sorting And Its Applications, Fei Nan Aug 2008

Direct Suffix Sorting And Its Applications, Fei Nan

Graduate Theses, Dissertations, and Problem Reports (ETD)

The suffix sorting problem is to construct the suffix array for an input sequence. Given a sequence T[0... n -- 1] of size n = |T|, with symbols from a fixed alphabet Sigma, (|Sigma| ≤ n), the suffix array provides a compact representation of all the suffixes of T in a lexicographic order. Traditionally, the suffix array is often constructed by first building the suffix tree for T, and then performing an inorder traversal of the suffix tree. The direct suffix sorting problem is to construct the suffix array of T directly without using the suffix tree data structure. We …

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Association Of Changes In Norepinephrine And Serotonin Transporter Expression With The Long-Term Behavioral Effects Of Antidepressant Drugs, Zaorui Zhao Aug 2008

Association Of Changes In Norepinephrine And Serotonin Transporter Expression With The Long-Term Behavioral Effects Of Antidepressant Drugs, Zaorui Zhao

Graduate Theses, Dissertations, and Problem Reports (ETD)

The relationship between the ability of repeated antidepressant treatment to cause down-regulation of the norepinephrine and serotonin transporters (NET, SERT) and produce antidepressant-like effects on behavior was determined. Treatment of rats with 15 mg/kg/day desipramine reduced NET expression, measured by 3H-nisoxetine binding and SDS-PAGE/immunoblotting, in cerebral cortex and hippocampus and reduced the time of immobility in the forced-swim test. The antidepressant-like effect on forced-swim behavior was evident two days following discontinuation of desipramine treatment when plasma and brain levels of desipramine and its major metabolite desmethyldesipramine were not detectable. Reduced NET expression resulted in decreased norepinephrine (NE) uptake, measured in …

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Comparison Of A New "U" Shaped Plastic Fish Tank System To The Traditional Concrete Raceway System, Daniel J. Miller May 2008

Comparison Of A New "U" Shaped Plastic Fish Tank System To The Traditional Concrete Raceway System, Daniel J. Miller

Graduate Theses, Dissertations, and Problem Reports (ETD)

The goal of this research was to compare the cost of purchasing, installing and operating a new plastic "U" shaped raceway (fish tank) to the traditional concrete flat-bottomed raceways used in many federal, state, and private fish hatcheries. Potential benefits of this new design include lower fixed (purchase and installation) costs, ease of mobility due to its light weight, reduced operational cost due to the rapid cleaning process that the "U" shape allows, and the simplicity with which modifications can be made to the tank to suit the operation. Limitations include width and depth restrictions and greater vulnerability to vandalism …

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Putative Role Of Palmitate And Akt Signaling In Attenuating Skeletal Muscle Growth In The Obese Zucker Rat, Jonathan Michael Peterson May 2008

Putative Role Of Palmitate And Akt Signaling In Attenuating Skeletal Muscle Growth In The Obese Zucker Rat, Jonathan Michael Peterson

Graduate Theses, Dissertations, and Problem Reports (ETD)

The Obese zucker rat (OZR) is a model of obesity and metabolic syndrome, with a reduced skeletal muscle mass compared with the lean zucker rat (LZR). Growth and hypertrophy of muscle fibers critically depend on activation and differentiation of satellite cells into new myonuclei, as well as the prevention of myonuclear apoptosis. Akt is known to regulate satellite cell activation and differentiation and inhibit apoptotic signaling. Akt activity is also reduced in the OZR compared to the LZR. The present study had two primary purposes; first, to observe, in vitro, the effects of the saturated free fatty acid palmitate on …

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Effects Of A Mind-Consciousness-Thought (Mct) Intervention On Stress And Well-Being In Freshman Nursing Students, Judith A. Sedgeman May 2008

Effects Of A Mind-Consciousness-Thought (Mct) Intervention On Stress And Well-Being In Freshman Nursing Students, Judith A. Sedgeman

Graduate Theses, Dissertations, and Problem Reports (ETD)

An emerging "health" paradigm, Mind-Consciousness-Thought (MCT), proposes that three universal Principles, Mind (life energy), Consciousness (the capacity to be aware of thinking as "reality"), and Thought (the ability to create thinking continually), explain how psychological experience is created from the inside-out, not created from the outside-in by events and circumstances. It proposes that life comes through us, not at us. It proposes that insight into the existence and operation of those principles reconnects people to their innate mental well-being, an always accessible source of balance, wisdom, and creativity (i.e., resiliency). It proposes that accessing mental well-being is incompatible with chronic …

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Postpartum Sleep Disturbance And Psychomotor Vigilance Performance, Salvatore Insana May 2008

Postpartum Sleep Disturbance And Psychomotor Vigilance Performance, Salvatore Insana

Graduate Theses, Dissertations, and Problem Reports (ETD)

Postpartum women have high rates of sleep disturbance and commonly suffer from many of the effects of disturbed sleep, though attentional state has not been studied extensively in this population. This study assessed sleep and attentional state psychomotor performance in postpartum women to develop a better understanding of how sleep disturbance --specifically sleep fragmentation and partial sleep deprivation-- is associated with attentional state psychomotor performance. Participants were a sample of 24 postpartum mothers from a larger study. Mothers were 29.96 (SD = 7.94) years old, had a mean income of {dollar}65,808 (SD = {dollar}41,398), and had 17.04 (SD = 2.53) …

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Preferential Flow And Phosphorus Translocation In Benchmark Soils Of West Virginia, Michael B. Harman May 2008

Preferential Flow And Phosphorus Translocation In Benchmark Soils Of West Virginia, Michael B. Harman

Graduate Theses, Dissertations, and Problem Reports (ETD)

Preferential flow is a mechanistic description of water movement in a soil profile where much of the soil matrix is bypassed during periods of rapid infiltration. The occurrence of preferential flow could lead to the movement of phosphorus (P) down through the soil profile. The objectives of this research were (i) to verify the presence of preferential flow in benchmark West Virginia soil series and (ii) measure soil test phosphorus (STP) levels within the preferential flow pathways and the surrounding soil matrix to determine the effects of preferential flow on phosphorus distribution within the soil profile. A non-reactive dye (Brilliant …

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Pilot Fatigue Detection Using Aircraft State Variables, Benjamin L. Smith May 2008

Pilot Fatigue Detection Using Aircraft State Variables, Benjamin L. Smith

Graduate Theses, Dissertations, and Problem Reports (ETD)

Pilot fatigue has been proven to be the cause of many aviation accidents. Fatigue introduces error into the pilot's inputs, which can potentially lead to accidents. To date, fatigue has been widely researched through physiological variables and sleep studies. Often, systems monitoring physiological variables would require constant physical contact with the pilot during flight. This arrangement could be cumbersome to pilots, and may hinder their flying ability even more. These systems will also add unnecessary weight to the aircraft, which could lead to increases in fuel consumption. Sleep studies have been investigated in an attempt to determine causes of pilot …

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Disturbances, Prescribed Fire, And Invasion By Exotic Plants In A Xeric Mixed-Oak And Oak-Pine Dominated Area Of The Ridge And Valley In Eastern West Virginia, Jonathan A. Pomp May 2008

Disturbances, Prescribed Fire, And Invasion By Exotic Plants In A Xeric Mixed-Oak And Oak-Pine Dominated Area Of The Ridge And Valley In Eastern West Virginia, Jonathan A. Pomp

Graduate Theses, Dissertations, and Problem Reports (ETD)

This document discusses three fire and exotic invasive plant related research studies that were conducted in an area of the Ridge and Valley dominated by xeric mixed-oak and oak-pine forest communities. The first study characterizes the timing, frequency, and magnitude of canopy disturbances in the study area by investigating demographic (age distributions), anatomical (growth increment patterns), and structural (diameter distributions) evidence. In addition to the general reconstructed disturbance history, the potential link between overstory tree-of-heaven (Ailanthus altissima (P. Mill.) Swingle) populations and prior forest management disturbances (i.e. harvesting) is investigated. This study indicates an uneven-aged structure resulting from multiple disturbances …

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Increasing The Performance And Realism Of Procedurally Generated Buildings, Brian Sowers May 2008

Increasing The Performance And Realism Of Procedurally Generated Buildings, Brian Sowers

Graduate Theses, Dissertations, and Problem Reports (ETD)

As multimedia such as games and movies grow, so does the need for content. Textures, 3D models, expansive terrain, sound effects, and other data must be generated to support and enrich these multimedia productions. As this need for content continues to grow, two critical problems emerge: the cost of hiring artists to create the content becomes extremely large, as does the amount of memory needed to store and manipulate the content.;To combat these issues, procedural content generation, or content generated algorithmically rather than via an artist, has been introduced. Algorithmically generating content allows for rapid creation of large amounts of …

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Selenite Removal Using Gac Based Iron-Coated Adsorbents, Ning Zhang May 2008

Selenite Removal Using Gac Based Iron-Coated Adsorbents, Ning Zhang

Graduate Theses, Dissertations, and Problem Reports (ETD)

Removal of selenite from aqueous phase using iron-coated granular activated carbons (GAC) was investigated in this study. Five different types of GAC were used for iron coating by oxidizing ferrous chloride with sodium hypochlorite and tested for selenite removal. Nitrogen adsorption-desorption analyses indicated that Brunauer-Emmett-Teller (BET) surface area, pore size, and pore volume deceased with the iron coating. The Darco 12x20 GAC was shown to be the most effective adsorbent among the five tested GACs after iron coating. Among the different concentrations used for iron coating, the Darco 12x20 GAC coated with 0.1 M ferrous chloride achieved the highest selenite …

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Social Anxiety And Facial Affect Recognition In Preschool Children, Chelsea M. Ale May 2008

Social Anxiety And Facial Affect Recognition In Preschool Children, Chelsea M. Ale

Graduate Theses, Dissertations, and Problem Reports (ETD)

Previous research relating anxiety and facial affect recognition, focusing mostly on school-aged children and adults, has yielded mixed results. The current study sought to demonstrate an association among behavioral inhibition and parent-reported social anxiety, shyness, social withdrawal and facial affect recognition performance using the Diagnostic Analysis of Nonverbal Accuracy Scale in 30 preschool children, ages 4 years to 5 years 8 months. Results indicated that social anxiety, social withdrawal, shyness, and behavioral inhibition together account for 25% of the variance in facial affect recognition performance, although this proportion was not statistically significant r2 = .25, F(4,24) = 1.95, p = …

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Feeding Behaviors And Performance Measurements In Bucks, Rams, And Bulls, Stephen John Chavez May 2008

Feeding Behaviors And Performance Measurements In Bucks, Rams, And Bulls, Stephen John Chavez

Graduate Theses, Dissertations, and Problem Reports (ETD)

The objective of the study was to determine if relationships exist with feeding behaviors of bucks, rams, and bulls and efficiency or residual feed intake (RFI). Animals utilized in this investigation were either producer consigned by species or West Virginia University animals. All animals were group-housed in pens (14.6 m x 51.2 m) with 156.2 m2 under roof at the Reymann Memorial Farm in Wardensville, WV over two years. Animals were fed complete nutritionally adequate rations ad libitum to meet daily growth requirements for each species. GrowSafe radio frequency technology (GrowSafe Systems Ltd.) was used to monitor animal identification, visit …

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Water Quality Changes Over Time In Upper Freeport And Pittsburgh Coal Mines In West Virginia, Ben M. Mack May 2008

Water Quality Changes Over Time In Upper Freeport And Pittsburgh Coal Mines In West Virginia, Ben M. Mack

Graduate Theses, Dissertations, and Problem Reports (ETD)

The objective of this research was to determine the changes in acidity, sulfate, iron, aluminum, and calcium concentrations over time in above-drainage, underground mines. Water analyses were compiled from four sampling dates for two coal seams. Results for all sites showed declines in all parameters. Acidity decreases from the 40 sites were compared to three acidity decay curves. The data most closely matched the 5 percent decay curve. Acidity values from a different mine most closely matched the 10 percent decay curve during its first 12 years after closure. None of the five parameters showed significant relationships with either decade …

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Effects Of Atmospheric Acid Deposition And Single Versus Mixed Leaf Litters On Foliar Litter Decomposition, Carbon, Nitrogen, Phosphorus And Calcium Dynamics In A Regenerating Forest, Prinith Sumudu Munasinghe May 2008

Effects Of Atmospheric Acid Deposition And Single Versus Mixed Leaf Litters On Foliar Litter Decomposition, Carbon, Nitrogen, Phosphorus And Calcium Dynamics In A Regenerating Forest, Prinith Sumudu Munasinghe

Graduate Theses, Dissertations, and Problem Reports (ETD)

Increases in atmospheric N deposition over the past decades have raised concerns over nitrogen (N) retention and carbon (C) and nutrient cycling in forest ecosystems. We conducted two litter decomposition studies at the Long-Term Soil Productivity (LTSP) study at the Fernow Experimental Forest (FEF) in West Virginia. In the LTSP study acid deposition is simulated by periodic ammonium sulfate additions (N+S). Other treatments include control (ref) (no additions or reference) and ammonium sulfate plus lime (lime). Fresh litter was collected from treatment plots in November. Air-dried litter was weighed, and placed in nylon litter bags. Litter bags were placed in …

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Hydroacoustic Assessment Of Resident Species In The Ugashik Lakes, Alaska, Garrett James Staines May 2008

Hydroacoustic Assessment Of Resident Species In The Ugashik Lakes, Alaska, Garrett James Staines

Graduate Theses, Dissertations, and Problem Reports (ETD)

The Ugashik Lakes in southwest Alaska are a large, remote, thereimictic system that does not thermally stratify during the ice-free season. Little research has been done on the resident species of this system and others similar to it. However, with such little baseline information management agencies are still responsible for management of these lakes. In order to provide baseline data on the Ugashik Lakes resident species, hydroacoustic (2001-06) and gillnet (2004-06) surveys were performed.;Chapter 2 uses specific data gathered from the hydroacoustic unit to produce a target strength (TS) and length relationship for salmonids found in the Ugashik Lakes. The …

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Spatial Modeling Of Propagule Pressure In Ailanthus Altissima, Matthew A. Kaproth May 2008

Spatial Modeling Of Propagule Pressure In Ailanthus Altissima, Matthew A. Kaproth

Graduate Theses, Dissertations, and Problem Reports (ETD)

Ailanthus altissima (tree of heaven) is a non-native invasive tree spreading within central Appalachia. This dioecious, deciduous, and allelopathic species copiously produces samaras, capable of traveling at least 200 m through primary wind-dispersal. Removal of A. altissima individuals prior to timbering and other forest disturbances may help prevent spread into forest interiors. To aid in species management, this study investigated the use of remote sensing to identify the location and abundance of samaras in mixed mesophytic forests through supervised classifications. From empirical measurements, the estimated number of seeds per classified unit area was determined and the relationship between quantified propagule …

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Application Of The Biolog Microplate System To Monitor The Physiological Response Of Heat-Stressed Bacteria, Matthew G. Mccarroll May 2008

Application Of The Biolog Microplate System To Monitor The Physiological Response Of Heat-Stressed Bacteria, Matthew G. Mccarroll

Graduate Theses, Dissertations, and Problem Reports (ETD)

The BIOLOG microplate system was originally evaluated by Miller and Rhoden (1991) for its ability to correctly identify clinical and environmental isolates. The system determines identity based on the exchange of electrons produced during utilization of a carbon substrate and subsequent respiration, leading to the reduction of a tetrazolium-based color change. Enteric bacteria ( Escherichia coli, Enterobacter sakazakii, and Salmonella enterica serovar Typhimurium) were exposed to heat stress (52°C) and samples were removed as a function of time (0, 15, 30 and 90 min). Stressed cells were monitored with traditional viable cell counts and inoculated into BIOLOG GN plates. The …

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Computer Modeling Of Dapsone-Mediated Heteroactivation Of Flurbiprofen Metabolism By Cyp2c9, Robyn Renee Ayscue May 2008

Computer Modeling Of Dapsone-Mediated Heteroactivation Of Flurbiprofen Metabolism By Cyp2c9, Robyn Renee Ayscue

Graduate Theses, Dissertations, and Problem Reports (ETD)

The occurrence of atypical kinetics in cytochrome P450 reactions can confound in vitro determinations of a drug's kinetic parameters. During drug development, inaccurate kinetic parameter estimates can lead to incorrect decisions about a lead compound's potential for success. It has become widely accepted that in certain CYP subfamilies more than one molecule can occupy the active site simultaneously, in some cases resulting in enhanced substrate turnover (heteroactivation). However, the specific mechanism(s) by which dual-compound binding results in heteroactivation remain unclear. It is known that orientation of the substrate in the active site, as dictated by interactions with active site residues, …

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Evaluation Of The Impacts Of Highway Construction On Sediment And Benthic Macroinvertebrates In Appalachian Streams, Lara B. Hedrick May 2008

Evaluation Of The Impacts Of Highway Construction On Sediment And Benthic Macroinvertebrates In Appalachian Streams, Lara B. Hedrick

Graduate Theses, Dissertations, and Problem Reports (ETD)

Corridor H is a four-lane highway under construction in north eastern West Virginia. I used a variety of methods to assess the impacts of highway construction in the Lost River watershed, Hardy County, West Virginia. I designed a two part sediment sampler to be used to monitor sediment in paired sites upstream and downstream of highway construction. The two-part design, a base that remains embedded in the substrate, and a removeable trap, allowed for long-term placement of samplers without continual disturbance of the streambed. I used a laboratory flume to compare my sediment sampler design with other devices used to …

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Identification And Characterization Of Point Defects In Aluminum Nitride And Zinc Oxide Crystals, Sean M. Evans May 2008

Identification And Characterization Of Point Defects In Aluminum Nitride And Zinc Oxide Crystals, Sean M. Evans

Graduate Theses, Dissertations, and Problem Reports (ETD)

Electron paramagnetic resonance (EPR) and electron-nuclear double resonance (ENDOR) studies have been performed on single crystals of aluminum nitride (AlN) and zinc oxide (ZnO), two wide-band-gap semiconductors having the wurtzite crystal structure. These studies were used to characterize point defects in each material. In the first study in AlN, new EPR and ENDOR spectra were acquired from a deep donor. Although observed in as-grown crystals, exposure to x rays significantly increased the concentration of this center. ENDOR identified a strong hyperfine interaction with one aluminum neighbor along the c axis and weaker equivalent hyperfine interactions with three additional aluminum neighbors …

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In Vitro Elucidation Of The Metabolic Fate Of The Anticancer Drug Busulfan, Islam Rasem Younis May 2008

In Vitro Elucidation Of The Metabolic Fate Of The Anticancer Drug Busulfan, Islam Rasem Younis

Graduate Theses, Dissertations, and Problem Reports (ETD)

Busulfan is a bifunctional alkylating agent that is used to treat mylogenous leukemia. The major elimination pathway of busulfan is through glutathione-S-transferase (GST) catalyzed conjugation to form glutathione sulfonium conjugate. The aim of this work is to elucidate the novel metabolic pathways of busulfan that may explain its toxicity. The observed data showed that busulfan is not a substrate for CYP450. The sulfonium ion conjugate of busulfan was found to be inactive as it did not inhibit GST in human liver cytosol, did not react with 4-(4-nitrobenzyl)pyridine, did not induce apoptosis in NCI-H460 cells, and was not stable in basic …

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Development Of Direct Elemental Speciation In Solid State Materials Using Pulsed Glow Discharge Mass Spectrometry, Jennifer N. Robertson-Honecker May 2008

Development Of Direct Elemental Speciation In Solid State Materials Using Pulsed Glow Discharge Mass Spectrometry, Jennifer N. Robertson-Honecker

Graduate Theses, Dissertations, and Problem Reports (ETD)

Among the various elemental mass spectrometry techniques, glow discharge mass spectrometry is recognized for its ability to provide direct determination of trace elements present in solid state samples. In the present work, a pulsed glow discharge time of flight mass spectrometry method is developed for the direct speciation of chromium in solid state samples. In initial investigations, time-resolved power perturbation and Langmuir probe studies were undertaken to elucidate the excitation and ionization processes in a pulsed glow discharge plasma. The experimental data provides further insight into the energy transfer processes that occur at different spatial locations and in different temporal …

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De Novo Asymmetric Syntheses Of Biologically Active Natural Product, Haibing Guo May 2008

De Novo Asymmetric Syntheses Of Biologically Active Natural Product, Haibing Guo

Graduate Theses, Dissertations, and Problem Reports (ETD)

The enantioselective syntheses of daumone and four analogs have been achieved in 7 to 8 steps. This route relies upon a diasteroselective palladium catalyzed glycosylation reaction for the formation of the anomeric bond. The asymmetry of the sugar and aglycone portion of daumone were introduced by Noyori reduction of an acylfuran and a propargyl ketone. A highly diastereoselective epoxidation and reductive ring opening established the desired C-2 and C-4 stereochemistry of daumone.;A highly enantioselective and stereocontrolled approach to D-, L-swainsonine and 8, 8a-epi-D-swainsonine has been developed from achiral furan or furfural. A one-pot hydrogenolysis, followed by an intramolecular reductive amination …

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