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Graduate Theses, Dissertations, and Problem Reports (ETD)

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Students' And Instructors' Attitudes Toward Using Biometric Technology As An *Identification Method In Online Courses, Wafi Albalawi Dec 2004

Students' And Instructors' Attitudes Toward Using Biometric Technology As An *Identification Method In Online Courses, Wafi Albalawi

Graduate Theses, Dissertations, and Problem Reports (ETD)

This study investigated the social and cultural issues related to the implementation of biometric technology at the College of Human Resources and Education at West Virginia University. The study employed both quantitative and qualitative research methodologies. The researcher verbally interviewed five instructors and five graduate students. The quantitative research methods employed two surveys. The research population involved 30 instructors and 189 graduate students. The researcher utilized independent-sample t-tests to compare different groups. The results obtained from this research support the following: (1) there is a real privacy concern among instructors and students regarding the implementation of biometric technology, (2) religious …

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What Is The Impact Of Parental Support On Early Literacy?, Deborah K. Bush Dec 2004

What Is The Impact Of Parental Support On Early Literacy?, Deborah K. Bush

Graduate Theses, Dissertations, and Problem Reports (ETD)

Today, more than 75 percent of women ages 25--34 and 75 percent of women with a child under six years of age participate in the labor force. When both parents work outside the home, they often want to send their child to preschool, but preschool classes aren't always available, and often those that are available are the government programs that are open only to those of lower socio-economic status.;In addition, parents often want to support the emergent literacy of their children and help prepare them for kindergarten but aren't sure of how to provide the type of assistance that might …

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Modified Delphi Investigation Of Exercise Science In Physical Education Teacher Education, Sean M. Bulger Dec 2004

Modified Delphi Investigation Of Exercise Science In Physical Education Teacher Education, Sean M. Bulger

Graduate Theses, Dissertations, and Problem Reports (ETD)

As physical education teacher educators experiment with alternative pedagogical approaches to bridge the gap between subdisciplinary theory and professional practice, the need for enhanced multi-disciplinary research and communication continues. The purpose of this study was to determine the critical exercise science competencies, and associated instructional methods, that are recommended for inclusion in the physical education teacher education undergraduate curriculum. An initial list of theoretical and applied exercise science competencies was constructed using the knowledge, skills, and abilities recommended by the American College of Sports Medicine for individuals working in the field of exercise science. The two-round, modified Delphi procedure involved …

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Automatic Hydraulic Fracturing Design For Low Permeability Reservoirs Using Artificial Intelligence, Andrei Sergiu Popa Dec 2004

Automatic Hydraulic Fracturing Design For Low Permeability Reservoirs Using Artificial Intelligence, Andrei Sergiu Popa

Graduate Theses, Dissertations, and Problem Reports (ETD)

The hydraulic fracturing technique is one of the major developments in petroleum engineering in the last two decades. Today, nearly all the wells completed in low permeability gas reservoirs require a hydraulic fracturing treatment in order to produce at an economical level. This study presents a new methodology, applicable to tight gas reservoirs, for designing hydraulic fractures.;This study is intended to develop an automatic hydraulic fracture design tool to help users design fracture jobs without being an expert in the art and science of hydraulic fracturing. This process is composed entirely of an integration of several artificial intelligence techniques.;The methodology …

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Influence Of Rearrangement Of Actin Cytoskeleton On The Overall Material Properties Of Atdc5 Cells During Chondrogenesis, Madhavi V. S. Ayyalasomayajula Aug 2004

Influence Of Rearrangement Of Actin Cytoskeleton On The Overall Material Properties Of Atdc5 Cells During Chondrogenesis, Madhavi V. S. Ayyalasomayajula

Graduate Theses, Dissertations, and Problem Reports (ETD)

Studies show that when chondrocytes are cultured in 2D, they lose their phenotype. This change is reversed when the cells are embedded in a 3D culture system such as in agarose gel. Previous experiments in our lab showed that when prechodrocytic cells were embedded in agarose, chondrogenesis was triggered in these cells. This work attempts to understand the mechanical implications of this behavior. It also provides an estimate of the sensitivity of the apparatus that would be required to carry out compression loading experiments of gel-cell constructs that can distinguish between pre-chondrocytes and chondrocytes.;ATDC5 cells were cultured in 3D for …

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Smoking And Dose-Dependent Early Effects Of Nicotine On Bone Mechanical Properties And Histology, Daniel Shaw Porter Aug 2004

Smoking And Dose-Dependent Early Effects Of Nicotine On Bone Mechanical Properties And Histology, Daniel Shaw Porter

Graduate Theses, Dissertations, and Problem Reports (ETD)

The objective was to study the effects of nicotine and cigarette smoke on mechanical properties of cortical bone. Experiments were conducted for 5 weeks with New Zealand White Rabbits. The first experiment of 18 rabbits studied the effect of nicotine levels delivered via a nicotine patch (5.25, 10.5, 21 ng/ml), measured by different mechanical tests, porosity, and composition. There was no significant difference between the control and the treatment groups.;The second experiment of 22 rabbits studied the effects of nicotine delivered via a nicotine patch (10.5 ng/ml) and via a smoking chamber on fracture toughness and porosity. The rabbits exposed …

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Estimating Net Photosynthesis And Productivity Of A Loblolly Pine Forest Grown With Carbon Dioxide Enrichment, Clint J. Springer Aug 2004

Estimating Net Photosynthesis And Productivity Of A Loblolly Pine Forest Grown With Carbon Dioxide Enrichment, Clint J. Springer

Graduate Theses, Dissertations, and Problem Reports (ETD)

I examined the long-term effects of elevated CO2 on the leaf chemistry and photosynthesis of four species growing in the understory and two species growing in the overstory at the Duke Forest FACE experiment. I then used these measurements to parameterize a process based forest productivity model, PnET-II, in order to model the net primary productivity of the portions of the forest growing under ambient and elevated CO2. Finally, I performed a greenhouse study that examined the effects of elevated CO 2 and water availability on the growth and biomass allocation of loblolly pine seedlings from four distinct geographic locations. …

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Chaotic Price Dynamics Of Agricultural Commodities, Jeff B. Cromwell Aug 2004

Chaotic Price Dynamics Of Agricultural Commodities, Jeff B. Cromwell

Graduate Theses, Dissertations, and Problem Reports (ETD)

Traditionally, commodity prices have been analyzed and modeled in the context of linear generating processes. The purpose of this dissertation is to address the adequacy of this work through examination of the critical assumption of independence in the residual process of linearly specified models. As an alternative, a test procedure is developed and utilized to demonstrate the appropriateness of applying generalized conditional heteroscedastic time series models (GARCH) to agricultural commodity prices. In addition, a distinction is made between testing for independence and testing for chaos in commodity prices. The price series of interest derive from the major international agricultural commodity …

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Stereotypical Perceptions Of The Communication Behaviors Of Gay Males, Daniel W. Brewster Aug 2004

Stereotypical Perceptions Of The Communication Behaviors Of Gay Males, Daniel W. Brewster

Graduate Theses, Dissertations, and Problem Reports (ETD)

This study examined the stereotypical communication behaviors of gay males. The study examined the associations of assertiveness, responsiveness, homonegativity and biological sex. Participants were 359 (195 men, 164 women) students. Participants provided responses to questions about verbal and nonverbal behaviors for known gay individuals and individuals perceived to be gay. The participants then completed the Assertiveness-Responsiveness Measure (Richmond & McCroskey, 1990) in a self-report and observer-report, and the Modern Homonegativity Scale (Morrison & Morrison, 2002). Results indicated some of the more predominant responses to verbal and nonverbal behaviors are inconsistent with the prevalent societal perceptions of homosexuality. Significant associations between …

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Application Of Turning Point Theory To Communication Following An Acquired Disability, Katie Neary Dunleavy Aug 2004

Application Of Turning Point Theory To Communication Following An Acquired Disability, Katie Neary Dunleavy

Graduate Theses, Dissertations, and Problem Reports (ETD)

Interpersonal relationships are affected when one relational partner acquires a disability. The acquisition of the disability is considered a turning point and the interest of this study is what occurs after the turning point. In particular, this study investigated the satisfaction, emotional support and solidarity of those who have acquired a disability in their life and one of their able-bodied relational partners. The stages of adjustment to a disability were also quantitatively analyzed. Both the participants who acquired a disability and their relational partners completed self-report measures. Difficulties in obtaining participants led to descriptive results. Challenges to a small participant …

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Pentosidine As A Biomarker For Age In Birds And Museum-Prepared Study Skins, Jesse A. Fallon Aug 2004

Pentosidine As A Biomarker For Age In Birds And Museum-Prepared Study Skins, Jesse A. Fallon

Graduate Theses, Dissertations, and Problem Reports (ETD)

The phenomenon of aging is progressive, irreversible and universal to all living things. One unavoidable outcome of aging is the modification of proteins by sugars, which, through a non-enzymatic process, can lead to the formation of crosslinked compounds termed advanced glycation endproducts. One such endproduct, pentosidine (Ps), is an indicator, or biomarker, of biological age. Because most birds have no reliable markers of age beyond adulthood, this investigation examines the accumulation of Ps as an estimator of chronological age in birds. The first study herein examines interspecies comparison of Ps accumulation in Ruffed grouse and Double-crested cormorants. The second investigates …

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Influence Of A Three-Week Wildlife Education Curriculum On Knowledge And Attitudes Of South Carolina's Marlboro County High School Ninth And Tenth-Grade Biology Students, Diane M. Krishon Aug 2004

Influence Of A Three-Week Wildlife Education Curriculum On Knowledge And Attitudes Of South Carolina's Marlboro County High School Ninth And Tenth-Grade Biology Students, Diane M. Krishon

Graduate Theses, Dissertations, and Problem Reports (ETD)

The purpose of this study was to assess the influence of a three-week wildlife education curriculum on knowledge and attitudes of ninth and tenth-grade biology students in South Carolina. A three-week wildlife curriculum was incorporated into three high school biology classes in the same semester. The students were pre-tested and post-tested for knowledge and attitudes. The results indicate that the three-week curriculum had a positive influence on knowledge but did not influence wildlife attitudes. However, a substantial correlation occurred between the post-test attitude and knowledge scores, indicating that as students' knowledge increased, their attitudes towards wildlife and environmental education became …

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Nutrient Remobilization During Development And Senescence Of Petunia X Hybrida Floral Organs, Karyn L. Smith Aug 2004

Nutrient Remobilization During Development And Senescence Of Petunia X Hybrida Floral Organs, Karyn L. Smith

Graduate Theses, Dissertations, and Problem Reports (ETD)

Fresh weight, dry weight, and macronutrient content of corollas, ovaries, and styles were measured during the development and senescence of several wild-type and transgenic Petunia x hybrida plants. Flowers of age-related senescence exhibited growth, maintenance, and senescence phases during development. Flowers terminated by pollination-induced senescence exhibited only growth and senescence phases. Fresh and dry weight of Mitchell, V26, and SAG12-IPT corollas followed patterns previously observed in climacteric flowers. SAG12-IPT, a cytokinin overproducing plant, exhibited a prolonged maintenance phase compared to V26. A temporary increase in fresh weight, dry weight, and macronutrients of Mitchell corollas occurred at the expected onset of …

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Biologically Inspired Evolutionary Temporal Neural Circuits, Reza Derakhshani Aug 2004

Biologically Inspired Evolutionary Temporal Neural Circuits, Reza Derakhshani

Graduate Theses, Dissertations, and Problem Reports (ETD)

Biological neural networks have always motivated creation of new artificial neural networks, and in this case a new autonomous temporal neural network system. Among the more challenging problems of temporal neural networks are the design and incorporation of short and long-term memories as well as the choice of network topology and training mechanism. In general, delayed copies of network signals can form short-term memory (STM), providing a limited temporal history of events similar to FIR filters, whereas the synaptic connection strengths as well as delayed feedback loops (ER circuits) can constitute longer-term memories (LTM). This dissertation introduces a new general …

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Local And Regional Impairment Of Fish Assemblages In A Mined Appalachian Watershed, Jason Gregory Freund Aug 2004

Local And Regional Impairment Of Fish Assemblages In A Mined Appalachian Watershed, Jason Gregory Freund

Graduate Theses, Dissertations, and Problem Reports (ETD)

I used the Cheat River watershed, West Virginia, as a model system to examine the regional impacts of extensive localized stream impairment. Acid mine drainage (AMD) in the Cheat River watershed provided a unique opportunity to test the hypothesis that regional biological condition can be impacted through multiple local sources of degradation. Acid mine drainage is the result of the interaction among pyrite-rich coal, oxygen, and water. This interaction produces a solution that is generally low in pH and buffering capacity and high in heavy metals and sulfate and is toxic to aquatic life. Acid mine drainage also has the …

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Synchronization Of Spatiotemporal Patterns And Modeling Disease Spreading Using Excitable Media, Jianxia Cui Aug 2004

Synchronization Of Spatiotemporal Patterns And Modeling Disease Spreading Using Excitable Media, Jianxia Cui

Graduate Theses, Dissertations, and Problem Reports (ETD)

Studies of the photosensitive Belousov-Zhabotinsky (BZ) reaction are reviewed and the essential features of excitable media are described. The synchronization of two distributed Belousov-Zhabotinsky systems is experimentally and theoretically investigated. Symmetric local coupling of the systems is made possible with the use of a video camera-projector scheme. The spatial disorder of the coupled systems, with random initial configurations of spirals, gradually decreases until a final state is attained, which corresponds to a synchronized state with a single spiral in each system. The experimental observations are compared with numerical simulations of two identical Oregonator models with symmetric local coupling, and a …

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Mechanism Of Action Of Nsc3852, A Breast Cancer Differentiation Agent, Anna Martirosyan Aug 2004

Mechanism Of Action Of Nsc3852, A Breast Cancer Differentiation Agent, Anna Martirosyan

Graduate Theses, Dissertations, and Problem Reports (ETD)

The development of tumor cell differentiation agents is new initiative in cancer treatment research. The goal of this project was to identify breast cancer differentiation agents by screening quinoline ring-containing compounds obtained form National Cancer Institute Compound Library. Of six differentiation-inducing quinolines NSC3852 was chosen as a "lead" compound. Our results demonstrate that NSC3852 is an inhibitor of HDAC activity in HeLa and MCF-7 cells nuclear extracts. NSC3852 caused superoxide generation in MCF-7 cells in a NADPH oxidase-dependent fashion, and NSC3852-induced oxidative stress led to the shift in a redox potential of the cells to a more oxidized state. This …

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Ctp Synthase And Transporter Function In Coxiella Burnetii, Jeffrey D. Miller Aug 2004

Ctp Synthase And Transporter Function In Coxiella Burnetii, Jeffrey D. Miller

Graduate Theses, Dissertations, and Problem Reports (ETD)

Coxiella burnetii is a gram negative, obligate intracellular parasite that can only replicate in the acidified environment of a phagosome. Like other intracellular parasites, C. burnetii depends on the host cell for many of the substrates required for growth, such as amino acids. It had been observed that avirulent C. burnetii Nine Mile strain (Phase II) organisms in BHK-21 fibroblasts displayed improved growth when extracellular cytidine was introduced to infected cultures. This improved growth was not observed in wild type organisms in the same cell system. This observation, coupled with early enzyme activity studies, suggested that Phase II organisms had …

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Rna Analysis As A Method To Determine The Age Of A Biological Sample, Stacey E. Anderson Aug 2004

Rna Analysis As A Method To Determine The Age Of A Biological Sample, Stacey E. Anderson

Graduate Theses, Dissertations, and Problem Reports (ETD)

DNA analysis by Polymerase Chain Reaction (PCR) allows for the unambiguous identification of the person from whom a biological sample was derived but provides no information about when the sample was deposited. The ability to determine the age of blood or a biological sample would be of significant benefit to the forensic science community. This would provide a temporal linkage between the blood of the perpetuator and the commission of a crime or it could be used to exclude evidence that does not correspond to the time a crime was committed. It was hypothesized that ex vivo RNA decay was …

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Effects Of Artificial Neural Network Speed-Based Inputs On Heavy-Duty Vehicle Emissions Prediction, Nastaran Hashemi Aug 2004

Effects Of Artificial Neural Network Speed-Based Inputs On Heavy-Duty Vehicle Emissions Prediction, Nastaran Hashemi

Graduate Theses, Dissertations, and Problem Reports (ETD)

The PM split study was performed in Southern California on thirty-four heavy-duty diesel vehicles using the West Virginia University Transportable Heavy-Duty Vehicle Emissions Testing Laboratories to gather emissions data of these vehicles. The data obtained from six vehicles in the 1985--2001 model year and 33,000--80,000 lb weight range exercised through three different cycles were selected in this thesis. To predict the instantaneous levels of oxides of nitrogen (NOx), carbon dioxide (CO2), hydrocarbons (HC) and carbon monoxide (CO), an Artificial Neural Network (ANN) was used. Axle speed, torque, their rates of change over different time periods and two other variables as …

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Developing The Portability Indices And The Portable Code Generator, Gregory E. Mundy Aug 2004

Developing The Portability Indices And The Portable Code Generator, Gregory E. Mundy

Graduate Theses, Dissertations, and Problem Reports (ETD)

Portability is recognized as a highly desirable characteristic of contemporary software design. However, research in the area has not been forthcoming in recent years and much of the work related to the field is ad hoc and speculative at best.;This study attempted to establish a framework for deriving a probabilistic measure of software portability that may be useful in aiding developers to make key design decisions that will result in some quantifiable level of portability while minimizing the cost of incorporating portable design into the software production process.;The research also explored the potential portability benefits that may be derived from …

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Demography And Genetic Structure Of An Allegheny Woodrat Population In Northcentral West Virginia, Mary Elizabeth Manjerovic Aug 2004

Demography And Genetic Structure Of An Allegheny Woodrat Population In Northcentral West Virginia, Mary Elizabeth Manjerovic

Graduate Theses, Dissertations, and Problem Reports (ETD)

The Allegheny woodrat (Neotoma magister) occurs throughout the Appalachian Mountains forming isolated colonies in rock outcrops, cliffs, and caves. In the past 20--30 years, populations along the northern and western peripheries of the range have experienced drastic declines. There have been suggested reasons for this decline but a lack of long-term data has prevented application of specific management actions. In recent years, there has been more insight into population structure, gene flow, and relatedness among colonies. The objectives of my study were to examine these factors at a localized level to further assist with future management decisions.;Using data collected over …

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Axial Ligand Binding Equilibria As Probes Of The Effective Steric Bulk Of Substituted Tetraarylporphyrins, Michael Craig Thomas Aug 2004

Axial Ligand Binding Equilibria As Probes Of The Effective Steric Bulk Of Substituted Tetraarylporphyrins, Michael Craig Thomas

Graduate Theses, Dissertations, and Problem Reports (ETD)

Equilibrium constants and thermodynamic data are reported for coordination of various axial ligands to the zinc(II) complexes of tetra( p-tolyl)porphyrin, tetra(3,5-bis(biphenylmethoxy)phenyl)porphyrin, tetra(2,6-(perfluorobenzoxy)phenyl)porphyrin, and tetra(2,6-di(methoxy)phenyl)porphyrin in toluene at 25.0°C. With respect to coordination of a planar ligand to a zinc(II) porphyrin, the equilibrium constant varied with the identity of the meso-substituent in the order 3,5-bis-(biphenylmethoxy)phenyl > p-tolyl > 2,6-(perfluorobenzoxy)phenyl >> 2,6-di-(methoxy)phenyl. With respect to coordination of a non-planar ligand to a zinc(II) porphyrin, the order was 3,5-bis(biphenylmethoxy)phenyl > p-tolyl >> 2,6-(perfluorobenzoxy)phenyl ≈ 2,6-di(methoxy)phenyl. Thermodynamic data for the coordination of 3- and 4-phenylpyridine to zinc tetra(2,6-di(methoxy)phenyl) porphyrin show a greater loss of entropy than for the coordination …

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Essays On The Economics Of Religion, Charitable Giving, And Youth Crime, Brian J. Osoba Aug 2004

Essays On The Economics Of Religion, Charitable Giving, And Youth Crime, Brian J. Osoba

Graduate Theses, Dissertations, and Problem Reports (ETD)

This dissertation includes essays on the application of economics to areas previously thought to be the domain of sociology, psychology, and political science. Chapter 1 introduces the paths that economics has blazed into the areas of religion, charitable giving, crime, and government formation. The second chapter examines the functions that risk and time preference play in the strength of an individual's religious belief. The results illustrate that individuals treat religion like other goods exhibiting uncertainty and a delayed expected future payoff. Chapter 3 investigates the role of prestige and warm glow in the market for charitable giving. The results indicate …

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Diet, Physical Activity, And Television Viewing In Relation To The Body Weight Status Of West Virginia Adolescents, Kimberly M. Morris Aug 2004

Diet, Physical Activity, And Television Viewing In Relation To The Body Weight Status Of West Virginia Adolescents, Kimberly M. Morris

Graduate Theses, Dissertations, and Problem Reports (ETD)

Context. The obesity epidemic is now threatening youth. Yet little is known regarding the factors associated with adolescent weight status.;Objective. To determine whether dietary intakes, physical activity, and hours spent viewing television are related to the body weight status of West Virginia adolescents.;Design, setting, and participants. This descriptive study included survey, diet recall, and body mass index data from 1,036, 14--20 year olds attending West Virginia high schools during the years 2002 to 2003.;Results. Overweight students consumed less kilocalories (∼378) (P < .001), less servings of total grains (P < .01) and a greater percentage of their energy from protein (P = .01). A significantly less amount of overweight students reported participating in strengthening/toning physical activities on three or more days of the week (P < .01).;Conclusion. Overweight adolescents within the state of West Virginia appear more likely to restrict their energy intake rather than exercise to lose weight. Thus, public health intervention strategies to help these students reach a healthy weight while maintaining adequate nutrition are imperative.

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Assessment Of The Learning Styles Of Students At The Eastern Caribbean Institute Of Agriculture And Forestry, Centeno, Trinidad And Tobago And Identification Of Teaching Methods Used By Instructors, Cynthia Marie Burskey May 2004

Assessment Of The Learning Styles Of Students At The Eastern Caribbean Institute Of Agriculture And Forestry, Centeno, Trinidad And Tobago And Identification Of Teaching Methods Used By Instructors, Cynthia Marie Burskey

Graduate Theses, Dissertations, and Problem Reports (ETD)

An issue in higher education is to create a learning environment that is both positive and effective. With teaching methods that take into account all the learning styles within the classroom, a teacher can make the atmosphere of the classroom more conducive to learning. This study sought to determine if the teachers at the Eastern Caribbean Institute of Agriculture and Forestry, Centeno, Trinidad and Tobago (ECIAF) were using instructional methods that facilitated learning in their students. A two-phase study was utilized. Phase I used a descriptive survey to determine the learning styles of 36 first-year students at ECIAF. Phase II …

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Modeled Sulfur Dioxide Exposure From A Proposed Coal Fired Power Plant, Using Geographic Information Systems And Air Dispersion Modeling, Steven Jason Hutchens May 2004

Modeled Sulfur Dioxide Exposure From A Proposed Coal Fired Power Plant, Using Geographic Information Systems And Air Dispersion Modeling, Steven Jason Hutchens

Graduate Theses, Dissertations, and Problem Reports (ETD)

This study models the contribution of sulfur dioxide (SO 2) from a proposed coal fired power plant (CFPP) above existing ambient levels. Most vulnerable to SO2 exposure appear to be the elderly, young, and diseased, here identified as sensitive receptors (SR). Epidemiologic studies suggest 260mug/m3 as the lowest toxic threshold for SR exposure. It was hypothesized that added SO2 concentrations to existing ambient levels at regional sensitive receptors, under worst case scenario, would not exceed 260mug/m3.;The methods used identify and quantify density locations of localized SR using geographic information systems. Modeled worst case air dispersion concentration exposure to localized SR …

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Cascade Radical Cyclizations Of Benzannulated Enyne-Allenes And Development Of New Synthetic Strategies For Novel Polycyclic Aromatic Compounds, Yonghong Yang May 2004

Cascade Radical Cyclizations Of Benzannulated Enyne-Allenes And Development Of New Synthetic Strategies For Novel Polycyclic Aromatic Compounds, Yonghong Yang

Graduate Theses, Dissertations, and Problem Reports (ETD)

The cascade radical cyclization of benzannulated enyne-allene generated in situ from enediynyl propargylic alcohols promoted by thionyl chloride via an SNi' reaction provides an efficient synthetic pathway to 11H-benzo[b]fluoren-11-ols and related compounds. The simplicity of the synthetic sequence and the mildness of the reaction condition make this cascade reaction sequence useful for the construction of polycyclic aromatic compounds. Interestingly, when this strategy was employed for the systems having two benzannulated enyne-allene units, it was quite unexpected that the reaction sequence led to the formation of highly twisted 1,1'-dialkyl-9,9'-bifluorenylidenes involving an unusual cleavage of a benzene ring, and spiro[1H-cyclobut[ a]indene-1,9'-[9H]fluorenes] along …

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Critical Features Of Antigen-Specific And Allospecific Recognition By Cytotoxic T Lymphocytes, Marc A. Frankenberry May 2004

Critical Features Of Antigen-Specific And Allospecific Recognition By Cytotoxic T Lymphocytes, Marc A. Frankenberry

Graduate Theses, Dissertations, and Problem Reports (ETD)

In general, CD8+ T lymphocytes respond to a single class I MHC/peptide complex, a phenomenon known as "MHC self-restriction". We previously reported that CD8+ CTLs from C57BL/6 mice were restricted to both H-2Kb and H-2Db when responding to the horse cyt c-derived peptide, p41--49. In Part I of this dissertation, we examine structural features of H-2Kb/cyt c and H-2Db/cyt c complexes responsible for dual recognition. B6.H-4.1c, a representative cloned CTL, was induced by similar concentrations of native peptide added to either H-2Kb- or H-2Db-expressing targets. Furthermore, the dissociation rates for both H-2Kb/cyt c and H-2D b/cyt c were comparable, but …

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Decentralized Control For Uav Path Planning And Task Allocation, Matthew C. Lechliter May 2004

Decentralized Control For Uav Path Planning And Task Allocation, Matthew C. Lechliter

Graduate Theses, Dissertations, and Problem Reports (ETD)

The effort of this research is to move toward enabling Unmanned Air Vehicles to fly in autonomous formations with intelligent mission planning capabilities. In particular, UAVs will be able to autonomously perform path planning and task allocation. During missions, the UAVs must be able to avoid threats and no-fly zones while still reaching their target optimally in time.;A path planning and task allocation approach was first developed that treats the problem as a Multi-dimensional, Multiple-Choice Knapsack Problem. Paths are selected and task assigned while minimizing the UAV team's overall mission cost. Next, a SIMULINK-based centralized simulation environment was created. This …

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