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Graduate Theses, Dissertations, and Problem Reports (ETD)

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Controls On Ecosystem Nitrogen (N) Status And Carbon (C) Balance In Red Spruce Forests Located In A Region Of Historically High Atmospheric N Deposition., Kenneth R. Smith Jan 2016

Controls On Ecosystem Nitrogen (N) Status And Carbon (C) Balance In Red Spruce Forests Located In A Region Of Historically High Atmospheric N Deposition., Kenneth R. Smith

Graduate Theses, Dissertations, and Problem Reports (ETD)

Atmospheric deposition of reactive nitrogen (N) can have a strong influence on patterns of carbon (C) and N cycling in forest ecosystems. High-elevation red spruce (Picea rubens Sarg.) forests in the central Appalachian Mountains have historically been among the most sensitive ecosystems to the negative effects of N deposition. I examined the primary environmental factors that influence 1) N status, 2) belowground C balance, and 3) red spruce aboveground growth in seven high-elevation study sites that are located in an area where N deposition has been historically moderate to high. I established the seven sites in 2011 along a transect …

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Synchrotron Investigations On La0.7Sr0.3Mno 3/Pbzr0.2Ti0.8O3 Heterostructures., Jinling Zhou Jan 2016

Synchrotron Investigations On La0.7Sr0.3Mno 3/Pbzr0.2Ti0.8O3 Heterostructures., Jinling Zhou

Graduate Theses, Dissertations, and Problem Reports (ETD)

This dissertation is devoted to understanding the La0.7Sr0.3MnO3 (LSMO)/ PbZr0.2Ti0.8O3 (PZT) magnetoelectric interface through synchrotron x-ray absorption and other techniques. The word magnetoelectric (ME) describes the coupling effects in certain materials that exhibit a change of the magnetic (electric) order with the change of the electric (magnetic) field. Materials that are ME could potentially advance current technology. Faster, more sensitive, and more energy efficient devices can be built with ME materials as compared to the present systems. Practical ME materials are essential for the realization of this advancement. Single phase ME materials are rare and the known few do not …

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Challenging Historical Gis Through Unstructured Historical Primary Source Materials: Uncovering Sixteenth-Century St. Vincent, Aosta, Italy, James P. Schindling Jan 2016

Challenging Historical Gis Through Unstructured Historical Primary Source Materials: Uncovering Sixteenth-Century St. Vincent, Aosta, Italy, James P. Schindling

Graduate Theses, Dissertations, and Problem Reports (ETD)

The challenge to Historical GIS examined in this study is how to enable a system to accommodate sparse, unstructured, and spatially ambiguous data. The goal of this research is to take up this challenge by developing an Historical GIS that allows researchers to gain an understanding of a geography of the past. The study area for this research is the town of St. Vincent in what is now the Italian Alps and the time period is the sixteenth century. Three primary criteria were used in the selection of sixteenth-century St. Vincent as the case study for this research. The first …

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Music Videos As Meaningful Entertainment? Psychological Responses To Audio-Visual Presentations Of Song Narratives, Lea Margarete Schlue Jan 2016

Music Videos As Meaningful Entertainment? Psychological Responses To Audio-Visual Presentations Of Song Narratives, Lea Margarete Schlue

Graduate Theses, Dissertations, and Problem Reports (ETD)

Combining auditive, visual, and textual elements in a unique way, music videos are currently one of the most popular and viral forms of entertainment media. Narrative music videos, in particular, engage their viewers by visually communicating the meaning of a song and its lyrics, which possibly employs them as a useful tool to communicate social, political and cultural messages to a broad audience, and implicates their social and cultural relevance. The purpose of this study was to test whether visual presentations of song narratives (as in music videos) foster a more transporting, engaging, enjoyable, and appreciative entertainment experience than listening …

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The Evaluation And Interpretation Of Controls Used In Three Commercially Available Quantification Kits For Forensic Dna Analysis, Stephanie R. Schottke Jan 2016

The Evaluation And Interpretation Of Controls Used In Three Commercially Available Quantification Kits For Forensic Dna Analysis, Stephanie R. Schottke

Graduate Theses, Dissertations, and Problem Reports (ETD)

This research presented an idea to aid crime laboratories in the selection of the best quantification method for use in DNA analysis in their laboratory. The goal of this research was to evaluate the suitability of using an external reference standard, the NIST SRM 2372 Human Quantitation Standard, to increase the quality of quantification results of human DNA analysis in commercially available kits. Additionally, the DNA standard included with the commercial kit, used for developing a standard curve, was evaluated for accuracy and stability beyond the recommended time frame. The commercial quantification kits tested were: QuantifilerRTM Trio DNA Quantification Kit …

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Communicative Solutions Through Technology: An Evaluation Of Esl Textbooks In Brazil, Natalia De Souza Sterci Jan 2016

Communicative Solutions Through Technology: An Evaluation Of Esl Textbooks In Brazil, Natalia De Souza Sterci

Graduate Theses, Dissertations, and Problem Reports (ETD)

Textbooks are the main tools used by teachers and students in English as a Second Language/ English as a Foreign Language (ESL/EFL) teaching settings; Therefore, it is important to select the most appropriate textbook that meets both teachers' and students' needs. This study examines three textbooks commonly used in Brazilian private schools: New Interchange (Richards, 2000), American Headway 1 (Soars & Soars, 2001), and Top Notch 1 (Saslow & Ascher, 2006), all of which are published by non-Brazilian companies, to see how well they address the urgent need for communication-based EFL textbooks in Brazil. The current study seeks to help …

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The Physiology Of Apology: An Investigation Into Potential Sex Differences, Daniel Stephenson Jan 2016

The Physiology Of Apology: An Investigation Into Potential Sex Differences, Daniel Stephenson

Graduate Theses, Dissertations, and Problem Reports (ETD)

Current literature on apology indicates that men and women differ in the types of apologies they offer and accept. In a recent study, Whited, Wheat, and Larkin (2010) showed that males and females may also experience differing physiological benefits following an apology. The purpose of the current study was to replicate the experimental study by Whited et al. and extend it by examining two different types of apologies. This study employed a 2 (men, women) X 3 (elaborate apology, simple apology, no apology) between subjects design to determine whether sex of participant and type of apology influenced the rate of …

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Geotechnical Testing And Finite Element Modeling Of Geomorphic Landform Design With A Multi-Layer Cap And Cover System, Jeffrey R. Stevens Jan 2016

Geotechnical Testing And Finite Element Modeling Of Geomorphic Landform Design With A Multi-Layer Cap And Cover System, Jeffrey R. Stevens

Graduate Theses, Dissertations, and Problem Reports (ETD)

This research was aimed at implementation of Geomorphic Landform Design (GLD) principles to the Royal Scot abandoned coal refuse disposal facility in Greenbrier County, West Virginia, USA. This facility currently exhibits many undesirable environmental problems including acid-mine drainage and significant erosion and sediment transport.;A multi-layer cap and cover system in conjunction with GLD principles was proposed as a solution to these environmental problems. This cover is proposed to be constructed from the coarse coal refuse material on-site and a short paper fiber material (MGro(TM)) from the MeadWestVaco paper mill in nearby Covington, Virginia, USA. To determine the possible effectiveness of …

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Cooperative Maneuver Enabled Uav Relative Localization, Jared Strader Jan 2016

Cooperative Maneuver Enabled Uav Relative Localization, Jared Strader

Graduate Theses, Dissertations, and Problem Reports (ETD)

The ability to localize itself in an environment is essential for any autonomous vehicle. In applications involving multiple Unmanned Aerial Vehicles (UAVs) such as formation flight, surveillance, and mapping, the relative pose of each UAV provides vital information for multiple vehicles to coordinate effectively. The majority of cooperative localization tasks involving multiple UAVs assume the transformation between reference frames, but this information is not always provided in the absence of landmarks or a Global Positioning System (GPS).;This thesis presents a method for estimating the relative pose of a pair of UAVs using range-only measurements. In this method, there is no …

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Pigeons And Humans Time Miscued Intervals, Shrinidhi Subramaniam Jan 2016

Pigeons And Humans Time Miscued Intervals, Shrinidhi Subramaniam

Graduate Theses, Dissertations, and Problem Reports (ETD)

Cues signaling time to reinforcer availability can be highly informative, somewhat informative, or uninformative of the specific time to reinforcement. The purpose of this series of studies was to characterize the functional relation between miscues and pigeon and human response patterns in a peak-interval (PI) procedure. In Experiment 1, pigeons pecked keys to earn food in a cued and miscued PI procedure. Each session consisted of fixed-interval (FI) 2-s and 4-s schedules of food and occasional, 12-s PI trials during which pecks had no programmed consequences. The correlation between visual cues (red or green key light colors) and the schedule …

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Fabrication Of Nanoelectrode Arrays For Dopamine Detection, Savan Suri Jan 2016

Fabrication Of Nanoelectrode Arrays For Dopamine Detection, Savan Suri

Graduate Theses, Dissertations, and Problem Reports (ETD)

Recent advancements in the semiconductor fabrication technologies have greatly helped in advancing the understanding of electrochemistry at nano scale (10-9 m). Electrodes are being produced at micro (10-6 m) and nano scale with varied materials, designs and for diverse applications. Better electrochemical sensing and detecting capabilities are achieved with nanoelectrodes in comparison with regular macroelectrodes. Lot of theoretical studies of electrochemistry at these nanoelectrodes have been proposed and developed. Despite the theoretical advancements, little has been done in experimental studies of nanoelectrodes. The progress is majorly impeded by lack of reliable fabrication procedures to produce such nanoelectrodes and test them …

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An Analysis Of Narong Prangcharoen's "Three Minds" For Solo Piano, Pawatchai Suwankangka Jan 2016

An Analysis Of Narong Prangcharoen's "Three Minds" For Solo Piano, Pawatchai Suwankangka

Graduate Theses, Dissertations, and Problem Reports (ETD)

This research paper studies the piano piece Three Minds composed by Narong Prangcharoen. The main focus is the analysis of its three movements: "Fierce," "Absent," and "Hesitant," of which only the first movement receives an in-depth analysis. In addition, the composer's biography, his musical style, a complete list of his composition, and historical background of Three Minds are included.;Prangcharoen, Thai native composer, became well known in the early 2000s. His music uniquely fuses Thai and Western elements. This is found in the first movement "Fierce" with the influence from ranad, a Thai wooden xylophone. As his music is bound within …

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Midi Electronic Wind Instrument: A Study Of The Instrument And Selected Works, Matthew J. Swallow Jan 2016

Midi Electronic Wind Instrument: A Study Of The Instrument And Selected Works, Matthew J. Swallow

Graduate Theses, Dissertations, and Problem Reports (ETD)

The development of the MIDI (Musical Instrument Digital Interface) electronic wind instrument (EWI) stemmed from earlier electronic instruments including analog/digital synthesizers, earlier control devices (Lyricon), and electronic instruments using a "blow tube trigger generator" (Yamaha WX) or breath controllers (Yamaha BC). Developing such devices began as early as the 1940s and were originally intended for compositional use instead of performance. However, the technology of electro-acoustic sounds continued to expand commercially from the 1950s through the 1970s, including more general access to sound synthesis and live performance. Various companies including Yamaha, Akai, Moog, Korg, and others would establish lines of synthesizers …

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Three Essays On Institutional Economics Of Gender, Maria Tackett Jan 2016

Three Essays On Institutional Economics Of Gender, Maria Tackett

Graduate Theses, Dissertations, and Problem Reports (ETD)

This dissertation is a collection of essays that incorporate institutional analysis into Economics of Gender research. I specifically consider the role of institutional arrangements in the economic status of women, opportunities the institutional arrangements create for women, and outcomes of changes in institutional arrangements that affect women. In chapter 2 I investigate the relationship between income distribution inequality and labor mobility, as globalization is viewed in the existing literature as aiding income inequality by allowing greater capital mobility but not mobility of labor. The literature argues that globalization creates changes in bargaining power for labor and capital owners thus decreasing …

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Microfluidic Based Hydrate Permeability System: Design And Construction, Matthew Tacker Jan 2016

Microfluidic Based Hydrate Permeability System: Design And Construction, Matthew Tacker

Graduate Theses, Dissertations, and Problem Reports (ETD)

Methane hydrates represent a vast and untapped fossil fuel resource underlying large portions of the world's artic continental surfaces and sub-sea continental shelves. These hydrates are crystalline solids that consist of methane molecules surrounded by cages of interacting water molecules, similar to ice. Methane hydrates occur naturally, where temperature and pressure conditions favor their formation. In order to utilize these resources, methods must be developed to determine the conditions most favorable to hydrate extraction. One important condition is permeability and how it is affected by hydrates. Due to the difficulty and cost of field studies, the study of laboratory-synthesized hydrates …

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Situational Awareness Enhancement For Connected And Automated Vehicle Systems, Amin Tahmasbi Sarvestani Jan 2016

Situational Awareness Enhancement For Connected And Automated Vehicle Systems, Amin Tahmasbi Sarvestani

Graduate Theses, Dissertations, and Problem Reports (ETD)

Recent developments in the area of Connected and Automated Vehicles (CAVs) have boosted the interest in Intelligent Transportation Systems (ITSs). While ITS is intended to resolve and mitigate serious traffic issues such as passenger and pedestrian fatalities, accidents, and traffic congestion; these goals are only achievable by vehicles that are fully aware of their situation and surroundings in real-time. Therefore, connected and automated vehicle systems heavily rely on communication technologies to create a real-time map of their surrounding environment and extend their range of situational awareness. In this dissertation, we propose novel approaches to enhance situational awareness, its applications, and …

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Sites Of Education: Race, Memory, And The Conflicting Discourses Of Learning In America, 1827-1914, Douglas Terry Jan 2016

Sites Of Education: Race, Memory, And The Conflicting Discourses Of Learning In America, 1827-1914, Douglas Terry

Graduate Theses, Dissertations, and Problem Reports (ETD)

This dissertation is a cultural study that challenges the handling of race in the history of American education by exploring how educational discourse shapes race. It argues that education itself is a manifestation of race, inseparable from the iterative processes of racial formation. While we take it as a prevailing truism that race is learned, this dissertation shows how the educational system itself is central to this learning.;It explores race in the educational landscape in a similar way to how scholars explore tension between history and cultural memory. In this manner, the dissertation focuses on what it terms "sites of …

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Brook Trout (Salvelinus Fontinalis) Preference Of Aquatic Versus Terrestrial Prey In Appalachian Headwater Streams, Erin E. Thayer Jan 2016

Brook Trout (Salvelinus Fontinalis) Preference Of Aquatic Versus Terrestrial Prey In Appalachian Headwater Streams, Erin E. Thayer

Graduate Theses, Dissertations, and Problem Reports (ETD)

This thesis aims to investigate the foraging behavior of Brook Trout (Salvelinus fontinalis), specially focusing on prey preference. Brook Trout are mainly restricted to head-water streams in Appalachia, which is a portion of their native range. These environments generally have low autochthonous materials. Therefore, resident aquatic organisms rely heavily on terrestrial inputs, i.e. leaf litter and terrestrial invertebrates (TI's), to subsidize individual energy requirements at critical times of the year. There is mixed evidence demonstrating stream dwelling trout show either a feeding preference towards aquatic invertebrates (AI's) or towards TI's. Chapter one is an in depth literature review of headwater …

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Jurors' Perceptions Of Testimony In Cases Involving Child-On-Child Sexual Abuse And Anatomical Forensic Interviewing Aids, Benjamin Thomas Jan 2016

Jurors' Perceptions Of Testimony In Cases Involving Child-On-Child Sexual Abuse And Anatomical Forensic Interviewing Aids, Benjamin Thomas

Graduate Theses, Dissertations, and Problem Reports (ETD)

Juveniles perpetrate an estimated 23 to 33% of all child sexual abuse cases, but there is a lack of research examining jurors' perceptions in these types of cases (National Center for Victims of Crime, 2009). Prior research on child witnesses suggests age affects jurors' perceptions of credibility and accuracy, such that younger children are perceived as more credible than older children in cases of child sexual abuse (Bottoms & Goodman, 1994; Holcomb & Jacquin, 2007; Schmidt & Brigham, 1996). Anatomical dolls and Human Figure drawings (HFDs) are used as forensic interviewing tools in cases of alleged child sexual abuse, despite …

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Gender-Specific Motivators And Barriers To Adopting Healthful Diets And Losing Weight Among Middle-Aged West Virginians, Stephanie K. Thompson Jan 2016

Gender-Specific Motivators And Barriers To Adopting Healthful Diets And Losing Weight Among Middle-Aged West Virginians, Stephanie K. Thompson

Graduate Theses, Dissertations, and Problem Reports (ETD)

Gender-specific motivators and barriers to adopting healthful diets and losing weight among middle-aged West Virginians Stephanie K. Thompson Background: About 70% of West Virginia adults are overweight and obese. Diet is a modifiable determinant of weight-related conditions. Innovative interventions are needed to help overcome the barriers to prevent and delay chronic conditions. In order to implement an intervention that is needed, learning the motivators and barriers to healthful eating and weight loss is the first step.;Objective: To learn what helps or hinders healthful eating and weight loss among middle-aged adults in West Virginia.;Methods: Gender-specific focus groups were conducted among 45 …

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Synthesis Of 1,2,3-Triazole Ligands, Their Metal Complexes, And Applications In Catalysis; Gold (I) Catalyzed 1,N-Enyne Ester Cycloisomerization Reactions, Sravan Kumar Thummanapelli Jan 2016

Synthesis Of 1,2,3-Triazole Ligands, Their Metal Complexes, And Applications In Catalysis; Gold (I) Catalyzed 1,N-Enyne Ester Cycloisomerization Reactions, Sravan Kumar Thummanapelli

Graduate Theses, Dissertations, and Problem Reports (ETD)

Dihydronaphthalenes have been prepared from a ligand controlled gold catalyzed enyne cycloisomerization reaction by using water as an additive. Additionally, four membered rings were obtained in the absence of water under similar conditions. This method also provides excellent yields of substituted dihydroquinolines and dihydrobenzopyrans. Both aliphatic and aromatic terminal alkynes provide the cyclic products under the optimized conditions. The reaction represents a novel method for the synthesis of seven-membered rings with moderate yields.;1,2,3-Triazoles have been utilized as ligands in a number of synthetic transformations. In our attempt to mimicking the porphyrin with 1,2,3-triazole by macrocyclization was unsuccessful due to poor …

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Adherence To Sport Rehabilitation, Kjersti A. Traaen Jan 2016

Adherence To Sport Rehabilitation, Kjersti A. Traaen

Graduate Theses, Dissertations, and Problem Reports (ETD)

Context: Sport injuries occur in National Collegiate Athletic Association (NCAA) sanctioned sports during preseason, in season, and post season competition. In order for optimal return to play outcomes, rehabilitation programs must be implemented and enforced. However, the literature reports inconsistent adherence rates and few studies have evaluated adherence rates by including both the athlete and athletic trainer at the Division III level. Objective: The purpose of this study was to determine if there was a difference in adherence rates to rehabilitation between a pre and posttest for a Division III institution. Design: The study was a prospective exploratory study. Setting: …

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Empirical Analysis And Automated Classification Of Security Bug Reports, Jacob P. Tyo Jan 2016

Empirical Analysis And Automated Classification Of Security Bug Reports, Jacob P. Tyo

Graduate Theses, Dissertations, and Problem Reports (ETD)

With the ever expanding amount of sensitive data being placed into computer systems, the need for effective cybersecurity is of utmost importance. However, there is a shortage of detailed empirical studies of security vulnerabilities from which cybersecurity metrics and best practices could be determined. This thesis has two main research goals: (1) to explore the distribution and characteristics of security vulnerabilities based on the information provided in bug tracking systems and (2) to develop data analytics approaches for automatic classification of bug reports as security or non-security related. This work is based on using three NASA datasets as case studies. …

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Temporal And Spatial Distribution Of Imidacloprid And The Arthropod Fauna Associated With Eastern Hemlock, Tsuga Canadensis (L.) Carr, Richard M. Turcotte Jan 2016

Temporal And Spatial Distribution Of Imidacloprid And The Arthropod Fauna Associated With Eastern Hemlock, Tsuga Canadensis (L.) Carr, Richard M. Turcotte

Graduate Theses, Dissertations, and Problem Reports (ETD)

Eastern hemlock, Tsuga canadensis (L.) Carr (Pinales: Pinaceae), is an important component of both the urban and forest landscape of the eastern United States. Eastern hemlock has been heavily impacted by the introduction of the hemlock woolly adelgid, Adelges tsugae (Annand) (Hemiptera: Adelgidae). Two goals of this research were (1) to determine the effect of treatment timing (spring versus fall) and application method (tree injection versus soil injection) on the spatial and temporal distribution of imidacloprid the primary insecticide used to treat A. tsugae and (2) to assess the impact of application method and timing of imidacloprid treatments on the …

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Hydrogeochemical Characterization Of Rural Drinking Water In The Gauley River Basin, Monongahela National Forest, Arati A. Umarvadia Jan 2016

Hydrogeochemical Characterization Of Rural Drinking Water In The Gauley River Basin, Monongahela National Forest, Arati A. Umarvadia

Graduate Theses, Dissertations, and Problem Reports (ETD)

In the Appalachian Plateau region, the heterogeneous coal geology and fractured bedrock aquifers has led to complexity in understanding groundwater resources in West Virginia. Groundwater is a major resource in the Monongahela National Forest where private residences, public works, and national forest operations all rely heavily on this resource. In recent years, Marcellus shale gas has been explored in a small region of the Gauley River Basin, within the boundaries of the Monongahela National Forest. Hydrogeochemical evaluation of groundwater was carried out in this region with the objective of establishing a baseline of groundwater chemistry prior to potential Marcellus development. …

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Ordinary Sailors: The French Navy, Vichy And The Second World War, Alexander John Upward Jan 2016

Ordinary Sailors: The French Navy, Vichy And The Second World War, Alexander John Upward

Graduate Theses, Dissertations, and Problem Reports (ETD)

After the debacle of the Fall of France in 1940, the one organization that managed to maintain its discipline and functionality virtually intact was the French Navy. This is the story of how subsequently that navy was able to exert a disproportionate influence on the Vichy regime of Marshal Petain. Such influence achieved its apogee between February 1941 and April 1942 when the navy's Commander-in-Chief Admiral Darlan served simultaneously in several of the regime's highest offices. During this period France continued to flirt with the possibility of actively engaging Great Britain in war on the side of Nazi Germany. It …

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Bacillus Firmus For The Biological Control Of Meloidogyne Hapla And Xiphinema Americanum, Lisa M. Valencia Jan 2016

Bacillus Firmus For The Biological Control Of Meloidogyne Hapla And Xiphinema Americanum, Lisa M. Valencia

Graduate Theses, Dissertations, and Problem Reports (ETD)

Root-knot nematode (RKN) and dagger nematode (DN) are serious pests of agricultural crops, including peach trees of West Virginia. RKN is a sedentary endoparasite that feeds and reproduces within the roots of host plants, causing gall formation, loss of vigor, and plant death. DN is an ectoparasite that has the potential to vector devastating plant viruses. Many control options recommended for annual crops are not appropriate for orchards and the use of chemical nematicides is limited. The endospore-forming bacterium, Bacillus firmus (BF), is marketed as a bionematicide, though its mode of action and efficacy in controlling certain nematodes indigenous to …

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Spontaneous Combustion Of South American Coal, Brunno C. C. Vieira Jan 2016

Spontaneous Combustion Of South American Coal, Brunno C. C. Vieira

Graduate Theses, Dissertations, and Problem Reports (ETD)

Many causes can lead to mine fires and explosions in coal mines but one of the most relevant cause is the spontaneous combustion of coal. This event can cause serious environmental consequences such as release of huge quantities of greenhouse effect gases such as CO2 and CO, presents safety risks to the miners by igniting mine explosions, and also causes significant economic loss. Many countries in the world have faced these problems. In order to prevent and mitigate them, scientists develop methods to determine whether a coal deposit has propensity to spontaneous combustion or not.;Many methods have been developed around …

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Autism Spectrum Disorders Among Adults: Burden Of Healthcare Services' Utilization And Expenditures, Rini Vohra Jan 2016

Autism Spectrum Disorders Among Adults: Burden Of Healthcare Services' Utilization And Expenditures, Rini Vohra

Graduate Theses, Dissertations, and Problem Reports (ETD)

Study 1.;Background: Individuals with autism spectrum disorders (ASD) have extensive comorbidities. The current literature lacks documentation of prevalence of different types of comorbidities and their association with healthcare utilization and expenditures among adults with ASD as compared to adults without ASD.;Aim: To determine: 1) the differences in prevalence of psychiatric, non-psychiatric comorbidities, other health conditions, healthcare utilization, and expenditures among adults with and without ASD; and 2) the association of type of comorbidity with healthcare utilization and expenditures of adults with ASD.;Method: A retrospective cohort study using claims data from three state Medicaid Analytic eXtract was conducted. Adults aged 22--64 …

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First Semester Calculus Students' Concept Definitions And Concept Images Of The Tangent Line And How These Relate To Students' Understandings Of The Derivative, Brittany Vincent Jan 2016

First Semester Calculus Students' Concept Definitions And Concept Images Of The Tangent Line And How These Relate To Students' Understandings Of The Derivative, Brittany Vincent

Graduate Theses, Dissertations, and Problem Reports (ETD)

The purpose of this dissertation is to examine how students define and think about the tangent line in first semester calculus and investigate the influence of these ways of thinking on their understandings of the derivative. Students' conceptions of the tangent line were explored through four primary tasks: defining and constructing tangent lines, sketching the derivative, and graphically interpreting the formal symbolic definition of the derivative. The first two tasks were designed to access students' knowledge of tangent lines, and the second two tasks drew upon their ability to apply this knowledge and connect the tangent line to the derivative. …

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