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Graduate Theses, Dissertations, and Problem Reports (ETD)

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Direct Liquefaction Of Coal With Coal-Derived Solvents To Produce Precursors For Carbon Products, David Christopher Fenton May 2001

Direct Liquefaction Of Coal With Coal-Derived Solvents To Produce Precursors For Carbon Products, David Christopher Fenton

Graduate Theses, Dissertations, and Problem Reports (ETD)

Direct liquefaction (hydrogenation) of coal has frequently been pursued as one avenue for the production of value added products from coal. The focus of this research was to evaluate five coal-derived liquids as substitutes for tetralin in the coal hydrogenation process. A mid-distillate by-product liquid from the production of high quality char was obtained from Antaeus Technical Services, Inc. and split into three fractions, the original liquid (RACL), its heavy fraction (DACL-H), and its light fraction (DACL-L). The other two liquids were heavy creosote oil (HCO) and carbon black base #1 (CBB) from Koppers Industries, Inc. These liquids were used …

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Fourth Grade Elementary Students' Perception Of The Motivational Aspects Of Using Computers To Write In The "Student As Authors" Project, Karla Ribeiro De Assis May 2001

Fourth Grade Elementary Students' Perception Of The Motivational Aspects Of Using Computers To Write In The "Student As Authors" Project, Karla Ribeiro De Assis

Graduate Theses, Dissertations, and Problem Reports (ETD)

The purpose of this study was to describe fourth grade elementary students' perception of the motivational aspects of using computers to write in the "Student as Authors" Project. The following questions were answered in this research: (a) how do fourth grade students perceive the importance of computers in the "Students as Authors" Project? (b) what are the motivational aspects of using a computer to write in the "Student as Authors" Project from fourth grade students' perspective? The researcher used questionnaire, and interviews as modes of data collection. This study indicates that students consider computer important in the "Student as Authors" …

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Theorie Und Praxis Im Dramatischen Werk Rainer Lewandowskis, Ulrike E. Taylor May 2001

Theorie Und Praxis Im Dramatischen Werk Rainer Lewandowskis, Ulrike E. Taylor

Graduate Theses, Dissertations, and Problem Reports (ETD)

The purpose of this thesis is to examine selected works of the contemporary German playwright Rainer Lewandowski. This project will introduce Rainer Lewandowski's style and innovative ways of writing and directing plays by first analyzing two significant monographs, one about the German filmmaker Alexander Kluge and the other about the Romantic composer and writer E. T. A. Hoffmann. Second, I will show the importance of Rainer Lewandowski's children's theater, for example his stage adaptation of E. T. A. Hoffmann's children's story The Strange Child. Next, his musicals Me, Marlene, Mambo Mortale and Don't Panik, and his plays Tonight Neither Hamlet …

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Optimum Hybrid Vehicle Configurations For Heavy Duty Applications, Jonathan Burke Smith May 2001

Optimum Hybrid Vehicle Configurations For Heavy Duty Applications, Jonathan Burke Smith

Graduate Theses, Dissertations, and Problem Reports (ETD)

Increased concern about the fuel economy of and emissions from automobiles has led to interest in the use of hybrid electric powertrains and the introduction of several production vehicles in both heavy-duty and light-duty applications. Hybrid electric vehicles (HEVs) use a combination of electric motor(s) and another power source such as an internal combustion engine (ICE) or fuel cell. While these vehicles show great potential for use in a wide variety of driving situations, the optimization of components and control strategies is quite complex.;In this thesis, Class 2B, Class 6, and Class 8 vehicles are determined by averaging a variety …

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Dsp Implementation Of Trellis Coded Modulation And Distributed Space Time Coding, Yipeng Tang May 2001

Dsp Implementation Of Trellis Coded Modulation And Distributed Space Time Coding, Yipeng Tang

Graduate Theses, Dissertations, and Problem Reports (ETD)

Trellis coded modulation (TCM) combines convolutional coding with modulation, and offers approximately 2--3 dB of coding gain without requiring a corresponding bandwidth expansion. This thesis describes the process of encoding TCM, convolutional codes, decoding using the Viterbi Algorithm (VA), M-ary modulation formats suitable for TCM, and the evaluation of TCM performance.;The concept of multiple TCM, which is a generalization of ordinary TCM, gives rise to the concept of space time codes (STC). With STC, coded signals are transmitted from multiple antennas at the same time over a Rayleigh fading channel. STC combines of transmit diversity, coding and M-ary modulation to …

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Pretreatment And Enzymatic Hydrolysis Of Lignocellulosic Materials, Wei Cheng May 2001

Pretreatment And Enzymatic Hydrolysis Of Lignocellulosic Materials, Wei Cheng

Graduate Theses, Dissertations, and Problem Reports (ETD)

This research aims to increase the efficiency of utilizing lignocellulosic materials, which have great potential as future energy and chemical feed stocks, and may finally substitute the diminishing hydrocarbon resources. This work involved two main parts: (a) comparison of efficiency of different pretreatment methods on lignocellulosic materials; and (b) enhancing enzymatic hydrolysis in a continuous tubular membrane reactor (TMR) process.;The alkaline oxidation pretreatment method was found to be more efficient than ammonia steeping pretreatment in lignin removal and digestible cellulose enrichment for the raw substrates chosen for this study, namely, yellow poplar (hardwood) and corn cob (herbaceous crop).;A combination of …

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Field Observations Of The Early-Age Behavior Of Jointed Plain Concrete Pavements, Troy Haden Schell May 2001

Field Observations Of The Early-Age Behavior Of Jointed Plain Concrete Pavements, Troy Haden Schell

Graduate Theses, Dissertations, and Problem Reports (ETD)

Newly constructed rigid PCC highway pavements with open graded stabilized base courses have been found to develop non-uniform, transverse saw-cut joint-crack developments and extensive slab movement behaviors, which cause unwanted premature joint failures. Phase I of this study determined the variables associated with the sporadic, large joint opening development by literature review, laboratory tests and some field collected data. The large joints were believed to develop at early-ages of the slabs curing (within the first 48 hours). The early-age stress developments were found controlled by slab temperature history, material property development and frictional resistance. Minimal recommendations for corrects to the …

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Stress Concentration Around Dowel Bars In Jointed Rigid Concrete Pavements, Mourad Youssef Riad May 2001

Stress Concentration Around Dowel Bars In Jointed Rigid Concrete Pavements, Mourad Youssef Riad

Graduate Theses, Dissertations, and Problem Reports (ETD)

In this study, the magnitude and state of stresses induced around dowel bars were identified through detailed 3D Finite Element (3DFE) modeling of dowel jointed rigid pavement structures. Both straight and skewed joints were modeled using extremely fine meshing that allows accurate modeling of the friction and separation at dowel concrete interfaces. The model response was examined for the case of joint loading with an equivalent axle load of 18000 lb. It was found that significantly large tensile stresses develop in the concrete on both sides of the loaded dowel. The magnitude of the tensile stress approaches the tensile modulus …

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Skeletal And Dental Changes With The Acrylic Splint Herbst Appliance, Jorge Clemente Casellas May 2001

Skeletal And Dental Changes With The Acrylic Splint Herbst Appliance, Jorge Clemente Casellas

Graduate Theses, Dissertations, and Problem Reports (ETD)

The purpose of this study was to determine the amount of skeletal and dental cephalometric changes of Class II patients treated with acrylic splint Herbst appliance. The sample consisted of one experimental group and one control group. These patients were matched in sex, age and craniofacial morphology. The cephalometric system described by Pancherz was used to determine the cephalometric changes. Significant differences in skeletal and dental changes were found in patients treated with the acrylic splint Herbst when compared with the control group. An overjet correction of 4.6 mm and a molar relation correction of 5.6 mm were obtained. The …

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Pattern Recognition In Software Engineering Trend Adapting, Dapeng Chen May 2001

Pattern Recognition In Software Engineering Trend Adapting, Dapeng Chen

Graduate Theses, Dissertations, and Problem Reports (ETD)

Whether and when to adapt to certain software engineering trends are difficult questions to be answered by many decision-makers. The main reasons are due to the fact that evolution of software engineering trends itself is determined by various factors, many of which come from the fields outside of the software technology, thus hard to predict. So it is even harder to estimate the cost and benefit when adapting to certain trends. This paper is intended to study ways to decrease the risk involved in such decision making processes, by developing a pattern from past software engineering trends. While the pattern …

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Nutrient Content Of School Lunches And Packed Lunches As Consumed By Elementary School Students, Pamela Cheryl Hamilton May 2001

Nutrient Content Of School Lunches And Packed Lunches As Consumed By Elementary School Students, Pamela Cheryl Hamilton

Graduate Theses, Dissertations, and Problem Reports (ETD)

This study compared nutrient content and intake of student school and home-packed lunches. Food intake was estimated by weighing the food and leftovers of 114 elementary school children. Eighty-one percent (n = 92) consumed school lunches and nineteen percent (n = 22) consumed packed lunches. A nutrient analysis was conducted using Nutritionist V. Significant differences between the two types of lunch were determined using ANOVA and Tukeys Test (HSD.UEN), p < 0.05.;School lunches were nutritionally superior (p < 0.01) for protein, vitamin A, vitamin D, riboflavin, vitamin B6, folate, vitamin B 12, pantothenic acid, phosphorus, magnesium, zinc, and dietary fiber; (p < 0.05) for calcium and niacin.;After considering food waste, intake from school lunch remained significantly higher (p < 0.01) for vitamin D, vitamin B12, pantothenic acid, phosphorus, magnesium, and zinc; (p < 0.05) for riboflavin, vitamin B 6, folate, and calcium.;It was also noted that intake of milk and other dairy foods was higher (p < 0.01) from school lunches.

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Attitudes, Knowledge, And Implementation Of Biotechnology And Agriscience By West Virginia Agricultural Education Teachers, Jason E. Hughes May 2001

Attitudes, Knowledge, And Implementation Of Biotechnology And Agriscience By West Virginia Agricultural Education Teachers, Jason E. Hughes

Graduate Theses, Dissertations, and Problem Reports (ETD)

The purpose of this study was to provide information on the attitudes toward and knowledge level of biotechnology and agriscience as well as activities conducted which demonstrate implementation of biotechnology and agriscience by West Virginia Agricultural Education teachers.;Data was collected via a questionnaire. Knowledge level, teaching methods used, attitudes of the subject and teaching responsibilities, barriers to teaching, and preferred information sources of biotechnology and agriscience were the major parts. Demographics and level of science knowledge were other parts of the questionnaire.;A major finding of the study was that West Virginia agricultural education teachers possess a positive attitude towards biotechnology, …

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Photoluminescence Study Of Cadmium Zinc Telluride, Swati Jain May 2001

Photoluminescence Study Of Cadmium Zinc Telluride, Swati Jain

Graduate Theses, Dissertations, and Problem Reports (ETD)

In this thesis, I present a detailed study of Cd1-xZn xTe crystals with 0 ≤ x ≤ 0.14 using photoluminescence (PL) spectroscopy in the temperature range from 5 K to 300 K with the purpose of: (1) identifying various radiative transitions that are signatures of various point defects in bulk CdZnTe, (2) determining the zinc concentration in these crystals, and (3) identifying the nature of room-temperature PL. PL spectra at 5 K was used to determine the bandgap and hence the zinc concentrations. In the current state-of-the-art CZT grown for radiation detectors, it is common to observe 5-K PL spectra …

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Effects Of Sediment Upon Benthic Macroinvertebrates In Forested Northern Appalachian Streams, Michael Douglas Kaller May 2001

Effects Of Sediment Upon Benthic Macroinvertebrates In Forested Northern Appalachian Streams, Michael Douglas Kaller

Graduate Theses, Dissertations, and Problem Reports (ETD)

Excess fine sediment negatively influences the fauna of North American streams. With the current emphasis on multiple-use forests, the question is not whether fine sediment is detrimental, but what is the threshold of fine sediment that is tolerable?;To determine a threshold tolerance of fine sediment, a two-part project investigated the influence of fine sediment upon benthic macroinvertebrates. The first part encompassed two experiments in sediment manipulation in 1999 and 2000. The experiments tested benthic macroinvertebrate metric sensitivity to a range of fine sediment treatments. The second part involved four seasonal surveys of seven streams to determine the threshold amount of …

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Effects Of Nitrogen And Cutting Management On Root Growth And Productivity Of A Kentucky Bluegrass (Poa Pratensis L.) And White Clover (Trifolium Repens L.) Pasture, Gina Marie Kertulis May 2001

Effects Of Nitrogen And Cutting Management On Root Growth And Productivity Of A Kentucky Bluegrass (Poa Pratensis L.) And White Clover (Trifolium Repens L.) Pasture, Gina Marie Kertulis

Graduate Theses, Dissertations, and Problem Reports (ETD)

Nitrogen (N) and defoliation effects on productivity, root growth and soil nitrate (NO3-) in a Kentucky bluegrass and white clover pasture were examined. Nitrogen was applied annually in two equally split applications at rates of 0, 80 or 160 kg N ha -1. After reaching 12.7 cm, plants were cut to 2.5, 5.1 or 7.6 cm. Herbage was analyzed for yield, crude protein (CP), neutral detergent fiber and acid detergent fiber. Root samples were divided into three depths: 0.0--5.1, 5.1--10.2 and 10.2--20.3 cm, and analyzed for volume, dry weight and length. Soil NO3- was measured. At the 2.5 cm cut …

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Unethical Practices In Exhibiting Animals As Observed By West Virginia Extension Agents And High School Agriculture Teachers, Jared Nathaniel Nestor May 2001

Unethical Practices In Exhibiting Animals As Observed By West Virginia Extension Agents And High School Agriculture Teachers, Jared Nathaniel Nestor

Graduate Theses, Dissertations, and Problem Reports (ETD)

The purpose of this study was to determine the frequency of unethical practices in exhibiting animals observed by West Virginia extension agents and high school teachers. A researcher-created demographic sheet and a fifty-eight-statement Lickert type questionnaire were sent to all extension agents and high school agriculture teachers in West Virginia (N = 154). Descriptive data were analyzed using the Statistical Package for Social Sciences (SPSSpc). Frequencies, t-values and means were used to describe and analyze the research results.;There are unethical practices in West Virginia concerning cruelty to animals but these practices are not a problem that has a high rate …

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Identification, Localization And Metal-Catalyzed Induction Of Specific Metallothionein Isoforms Expressed By The Adult Human Lens, Brian Patrick Opperman May 2001

Identification, Localization And Metal-Catalyzed Induction Of Specific Metallothionein Isoforms Expressed By The Adult Human Lens, Brian Patrick Opperman

Graduate Theses, Dissertations, and Problem Reports (ETD)

Purpose. Metallothioneins (MT s) are a large family of proteins involved in multiple protective pathways, including binding of toxic metals and oxidative stress. Previously we detected increased expression of MT IIA in age-related human cataractous lenses. As a first step towards defining the function of MTs in the lens, we sought to establish the expression patterns of those MT isoforms expressed by the adult human lens and identify those toxic heavy metal inducers of MT IIA. Conclusions. This data establishes the spectrum of MTs expressed by the human lens, defines their spatial expression patterns (mRNA and protein level) and establishes …

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Propagation Of Updates To Replicas Using Error-Correcting Codes, Karthik Palaniappan May 2001

Propagation Of Updates To Replicas Using Error-Correcting Codes, Karthik Palaniappan

Graduate Theses, Dissertations, and Problem Reports (ETD)

With the increase in percentage of replicas of data in the Internet, reducing the amount of bandwidth needed for propagation of updates across the replicas has become a major issue. Objective of our investigation is to design an update propagation mechanism focused on reducing the amount of bandwidth needed to propagate the change across multiple distinct versions of the replicas in a distributed system. We obtain the estimated amount of bytes changed from the user and generate parity information needed to correct these bytes using Error Correcting Codes. Transferring the parity information propagates the update. The updated data can be …

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Effects Of Type-I Collagen Fractional Composition And Pyridinium Crosslink Content On Cortical Bone Strength In The Human Femur, Michael Blair Rice May 2001

Effects Of Type-I Collagen Fractional Composition And Pyridinium Crosslink Content On Cortical Bone Strength In The Human Femur, Michael Blair Rice

Graduate Theses, Dissertations, and Problem Reports (ETD)

Type-I collagen's role in the formation of bone and its inherent strength have been well documented by studies in genetic diseases such as Osteogenesis Imperfecta. Type-I collagen's role in healthy bone, and the changes that occur to collagen during aging, which may eventually lead to osteoporosis, is less understood. Changes that may occur include differences in collagen production and in its processing such as differences in glycosylation and the hydroxylation of specific amino acid residues. Changes in the reducible and non-reducible crosslink content, or changes in the ratio of crosslinks to total collagen may also occur. The present study investigated …

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Perceptions Of Benefits/Problems Of Part-Time Employment On The Job Performance Of Secondary Teachers Of Agricultural Education, Connie Mcclung Scarbrough May 2001

Perceptions Of Benefits/Problems Of Part-Time Employment On The Job Performance Of Secondary Teachers Of Agricultural Education, Connie Mcclung Scarbrough

Graduate Theses, Dissertations, and Problem Reports (ETD)

The purpose of the study was to examine the self-perceived potential benefits and/or problems of part-time employment on the job performance of secondary teachers of Agricultural Education. The population consisted of 108 agricultural educators who held teaching positions during the 2000--2001 school year in West Virginia, Ohio, and Kentucky and were employed within a 150-mile radius of Ripley, West Virginia. A descriptive research design was used for the study. There have been no studies conducted as to the number of agricultural educators involved in part-time employment and to what extent they are involved. Many have questioned the feasibility of a …

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Mutagenicity Of Root Canal Sealer Rsa Roekoseal Automix In The Ames Test, Joseph Anthony Wateska May 2001

Mutagenicity Of Root Canal Sealer Rsa Roekoseal Automix In The Ames Test, Joseph Anthony Wateska

Graduate Theses, Dissertations, and Problem Reports (ETD)

The mutagenic activities of the root canal sealers, RSA Roekoseal Automix and AHPIus, were tested in the bacterial gene mutation assay (Ames test). Both materials were tested immediately after mixing and after setting 24 h. The Salmonella typhimurium tester strains TA98 and TA 100 were used to detect the induction of frame shift mutations and base pair substitutions both in the presence and absence of a metabolically active microsomal fraction from rat liver (S9 fraction). No mutagenic or toxic effects were found with DMSO eluates of freshly mixed or 24h set RSA Roekoseal Automix. However, under extreme experimental conditions, DMSO …

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Valuation Of Electric Utility Generating Assets In A Competitive Environment, Mary Barbara Cain May 2001

Valuation Of Electric Utility Generating Assets In A Competitive Environment, Mary Barbara Cain

Graduate Theses, Dissertations, and Problem Reports (ETD)

Electricity industry restructuring, technological advances, and changing environmental laws and regulations are providing opportunities for many electricity companies to substantially lower their cost of doing business. One such cost is property tax, which in a majority of states is based upon the fair market value of property. Traditionally, assets of a regulated utility were valued at fair market value based upon the regulated price of electricity or "rate base". Valuation methods such as the income approach, replacement cost approach, comparable sales approach, and the stock and debt approach are common assessment methods for property tax (ad valorem) purposes. The appropriateness …

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Sensor Technology For The Breast Examination Training Instrument, Bratislav Matic May 2001

Sensor Technology For The Breast Examination Training Instrument, Bratislav Matic

Graduate Theses, Dissertations, and Problem Reports (ETD)

Latest medical research has shown high percentage of American women, diagnosed with breast cancer. If detected in its early stage, cancer can be treated successfully. Breast examination might be obtained through three procedures: breast self-examination (BSE), clinical breast examination (CBE) and mammography. Project BETI was developed with idea of educating and training women and health care professionals in BSE. This instrument consists of a silicone breast model, tactile sensors and serial communication capability. Software was developed for a generic PC that supports an integrated system including: (1) an interactive video demonstrating BSE techniques, (2) a practical examination using the instrumented …

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Fastener Withdrawal Resistance Of Wood-Based Composite Panel Products, Steven M. Cook May 2001

Fastener Withdrawal Resistance Of Wood-Based Composite Panel Products, Steven M. Cook

Graduate Theses, Dissertations, and Problem Reports (ETD)

The purpose of this research project was to evaluate the performance of currently available wood-based panel products as sub-floor materials when used under quality oak strip flooring and exposed to cyclic EMC conditions. The critical evaluation criterion was the fastener holding capacity of various sub-floor materials. To accomplish this, investigation of the in-plane density variations of currently available panel products was performed, as was an investigation of the relationship between panel density and the fastener holding capacity of different panel materials. In addition, a comparison of the fastener holding capacity of six different panel products was investigated during and after …

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Induction Of Fertile Estrus During Seasonal Anestrus In Ewes And Fall Born Ewe Lambs, Marlon Knights May 2001

Induction Of Fertile Estrus During Seasonal Anestrus In Ewes And Fall Born Ewe Lambs, Marlon Knights

Graduate Theses, Dissertations, and Problem Reports (ETD)

The quantity of progesterone (P4) delivered by a new P 4 releasing intravaginal insert (polycapralactone [PCL] insert), was inadequate to increase serum concentrations of P4 to that observed in cycling ewes during the luteal phase. Percentage of ewes in estrus was greater in P4 treated than in control ewes. Estrous response was greater after treatment with P4 for 5 than for 12 d. Progesterone increased the percentage of ewes lambing to both service periods by 20 percentage points. Prolificacy to the first service period in ewes treated with FSH was greater than the prolificacy in control and all ewes lambing …

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Objective And Subjective Personality Characteristics Of Medical Students, Heather Anderson Meit May 2001

Objective And Subjective Personality Characteristics Of Medical Students, Heather Anderson Meit

Graduate Theses, Dissertations, and Problem Reports (ETD)

The present study viewed personality characteristics of medical students using both objective (i.e., a valid and reliable psychological instrument) and subjective methods (i.e., medical students' self-ratings of how they viewed themselves and how they believed others viewed them). The 16 Personality Factor Questionnaire (16PF, 5th Edition) and a researcher developed instrument, the Subjective Rating Form (SRF), were utilized in this study. Significant differences were found in 16PF scores from entry to medical school (Time 1) to exit from medical school (Time 2). Significant differences were also observed when SRF scores were compared between Self at Time 1 (retrospectively), Self at …

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Metaphysical Detectives And Postmodern Spaces, Or The Case Of The Missing Boundaries, Richard A. Swope May 2001

Metaphysical Detectives And Postmodern Spaces, Or The Case Of The Missing Boundaries, Richard A. Swope

Graduate Theses, Dissertations, and Problem Reports (ETD)

Taking as its point of departure Henri Lefebvre's contention that "(Social) space is a (social) product," my dissertation explores the contemporary American novels of Pynchon, Acker, Reed, Auster, DeLillo, and McElroy as well as the two recent films Dark City and The Thirteenth Floor and their dramatization of the production of twentieth-century social space. I approach these works as metaphysical detective stories which evoke the classic detective figure only to frustrate his impulse to solve and contain. Following Foucault's contention that "space is fundamental to any exercise of power," I suggest that the detective figure is significant to an understanding …

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Amiodarone-Induced Pulmonary Toxicity In F344 Rats, Michael Douglas Taylor May 2001

Amiodarone-Induced Pulmonary Toxicity In F344 Rats, Michael Douglas Taylor

Graduate Theses, Dissertations, and Problem Reports (ETD)

Amiodarone (AD) is gaining support as a first-line antiarrhythmic drug despite its potentially fatal pulmonary toxicity involving inflammation and fibrosis. The goals of this study were to develop and characterize a rat model of amiodarone-induced pulmonary toxicity (AIPT). A protocol was developed in which male F344 rats were instilled intratracheally (i.t.) with AD (6.25 mg/kg with a 3.125 mg/ml solution) in sterile water or the sterile water vehicle on days 0 and 2, a protocol that led to the development of pulmonary fibrosis on day 28 in the AD-treated animals. Bronchoalveolar lavage (BAL) resulted in the increased recovery of alveolar …

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Sorption Of Lead And Arsenic On Soil Components And Effectiveness Of Phosphates For Remediating Lead And Arsenic Contaminated Soils, Harjinder Sandhu May 2001

Sorption Of Lead And Arsenic On Soil Components And Effectiveness Of Phosphates For Remediating Lead And Arsenic Contaminated Soils, Harjinder Sandhu

Graduate Theses, Dissertations, and Problem Reports (ETD)

High concentration of trace elements such as arsenic (As) and lead (Pb) represents one of the potentially costly threats to water and soil resources as well as serious threats to humans. Clay minerals are potential binding agents for pollutants due to their high cation exchange capacity and large surface area. Laboratory investigations were undertaken to evaluate the effect of Fe and Al hydrous oxide coatings on the sorption of Pb and As. Four clay minerals attapulgite, illite, kaolinite and montmorillonite with a range of surface characteristics were selected to investigate the Pb and As sorption. The minerals were coated with …

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Nonlinear Transient And Steady State Analysis For Self-Excited Single-Phase Synchronous Reluctance Generator, Jingdong Chen May 2001

Nonlinear Transient And Steady State Analysis For Self-Excited Single-Phase Synchronous Reluctance Generator, Jingdong Chen

Graduate Theses, Dissertations, and Problem Reports (ETD)

With today's trend for distributed generation and the need for alternative and renewable energy sources, self-excited induction and synchronous reluctance generators have attracted more attention for wind, tidal and hydro power generation applications. Compared to synchronous and DC generators, they have the advantages: they are brushless, they are robust, they do not need DC excitation and they are relatively low cost.;Compared with SEIG, the self-excited reluctance generator (SERG) not only has the advantages of simplicity and ruggedness, but can also have enhanced steady-state characteristics and high efficiency over a wide range of operation. Moreover, its output frequency is determined only …

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