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Effectiveness Of Treatment And Diversity Of Microbial Populations Within A Constructed Wetland Treating Wastewater, Jolene M. Friedland Dec 2004

Effectiveness Of Treatment And Diversity Of Microbial Populations Within A Constructed Wetland Treating Wastewater, Jolene M. Friedland

Graduate Theses, Dissertations, and Problem Reports (ETD)

Constructed wetlands are used as alternative on-site wastewater treatment systems. Microbiological dynamics in constructed wetlands are essential to adequate functioning and efficiency of these systems. The efficacy of wastewater treatment by a large subsurface flow wetland receiving wastewater from a multi-user facility was examined. Real-time monitoring with telemetry was combined with measurement of standard wastewater parameters such as biochemical oxygen demand (BOD5), total suspended solids (TSS), and enumeration of fecal coliforms. Passage of wastewater through the wetland significantly reduced standard wastewater parameters in effluent samples. Heterotrophic bacterial diversity was examined using community level physiological profiling (CLPP) and molecular characterization of …

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Starvation-Induced Alterations In Hepatic Lysine Metabolism In Different Families Of Rainbow Trout (Oncorhynchus Mykiss), Angela Higgins Dec 2004

Starvation-Induced Alterations In Hepatic Lysine Metabolism In Different Families Of Rainbow Trout (Oncorhynchus Mykiss), Angela Higgins

Graduate Theses, Dissertations, and Problem Reports (ETD)

This study focused on lysine catabolism by the lysine alpha-ketoglutarate reductase (LKR) pathway in rainbow trout (RBT). Selective breeding based on feed efficiency in 2 strains (A and B) of RBT generated 2 families within each strain. Eight fish from each of the four families were randomly allotted to individual tanks. Fish were fed until satiation for 3 wks at which time four fish within each family were randomly selected for 2 wks of starvation. After the 2 wk starvation, all fish were harvested. Hepatic in-vitro LKR activity and lysine oxidation (LOX) were measured as was LKR mRNA abundance. Strain …

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Glaucomys Sabrinus Fuscus Habitat And Nest Box Use In West Virginia With Management Recommendations For Kumbrabow State Forest, Tamara M. Terry Dec 2004

Glaucomys Sabrinus Fuscus Habitat And Nest Box Use In West Virginia With Management Recommendations For Kumbrabow State Forest, Tamara M. Terry

Graduate Theses, Dissertations, and Problem Reports (ETD)

Nest site selection and habitat use of the endangered West Virginia northern flying squirrel (Glaucomys sabrinus fuscus) is poorly understood. Because access to suitable nesting sites and habitats could be limiting factors, it is important to investigate these ecological requirements to further conservation efforts of the species. My study was conducted on the Kumbrabow State Forest and the MeadWestvaco Wildlife and Ecological Research Forest in Randolph County, West Virginia. I examined characteristics of 31 nest sites (22 cavity; 8 leaf; 1 undetermined) from 4 radio-collared West Virginia northern flying squirrels during the summers of 2002--2003. The nest trees used were …

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Needed Communication Skills During Initial Employment As Perceived By Graduates Of The West Virginia University Davis College Of Agriculture, Forestry And Consumer Sciences, Jessica R. Rollins Dec 2004

Needed Communication Skills During Initial Employment As Perceived By Graduates Of The West Virginia University Davis College Of Agriculture, Forestry And Consumer Sciences, Jessica R. Rollins

Graduate Theses, Dissertations, and Problem Reports (ETD)

The purpose of the study was to determine communication skills used during initial employment by graduates of the Davis College of Agriculture, Forestry and Consumer Sciences who were enrolled in the agricultural and natural resources communications (AgEE 421) course. The population consisted of 70 2001--2002 graduates of West Virginia University Davis College of Agriculture, Forestry and Consumer Sciences who were enrolled in agricultural and natural resources communications (AgEE 421) during their collegiate careers. A descriptive research design was used for the study. A major finding of the study was the beneficial effects of educational training in communications skills prior to …

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Biometric Analysis And Aversive Conditioning Of Black Bears In Southern West Virginia, Harley Wayne Weaver Dec 2004

Biometric Analysis And Aversive Conditioning Of Black Bears In Southern West Virginia, Harley Wayne Weaver

Graduate Theses, Dissertations, and Problem Reports (ETD)

During 2003, 11 male and 1 female black bear (Ursus americanus) were captured and fitted with radio collars. Individuals were randomly assigned to receive either treatment (n = 6) or control (n = 6). Upon release, treatment individuals received a conditional regimen comprised of rubber buckshot to the flank and a succession of shell crackers. Physical and auditory conditioning techniques we used did not appear to be an effective means of reducing repeat nuisance behavior.;West Virginia Division of Natural Resources (WVDNR) captured 179 (151 males, 28 females) nuisance and 156 (77 males, 79 females) non-nuisance individuals from 1996 to 2003.;We …

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Hematotoxicity Of Heptachlor, Sarah Vanessa Meads Dodson Dec 2004

Hematotoxicity Of Heptachlor, Sarah Vanessa Meads Dodson

Graduate Theses, Dissertations, and Problem Reports (ETD)

Hematotoxicity has been documented in adults exposed to high levels of organochlorine pesticides. Our studies revealed that prenatal exposure to the organochlorine pesticide heptachlor resulted in alteration of lymphocyte development, while myeloid cell development was spared. To further investigate effects of heptachlor on lymphoid cells, we evaluated direct exposure of this compound on pro-B and pre-B cells. In these studies, the pro-B cell line C1.92 and the pre-B cell line 70Z/3 demonstrated concentration-dependent decreases in proliferation following heptachlor exposure. Pro-B cell viability decreased significantly; however, pre-B cell viability was not altered. Further investigation into mechanisms of diminished cell proliferation revealed …

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Interactions Of Allelopathy And Competition Affecting Ziziphus Spina-Christi And Prosopis Juliflora Seedlings, Thobayet S. Alshahrani Dec 2004

Interactions Of Allelopathy And Competition Affecting Ziziphus Spina-Christi And Prosopis Juliflora Seedlings, Thobayet S. Alshahrani

Graduate Theses, Dissertations, and Problem Reports (ETD)

This study consists of two parts, provides data on the interference between Ziziphus spina-christi, native to Saudi Arabia, and Prosopis juliflora, an introduced species. Dry leaves from both species were milled and used to prepare extracts using 0g/l, 5g/l, 20g/l, 40g/l, 60g/l, and 100 g/l of dried leaves. Leaf extract of P. juliflora was used to irrigate Z. spina-christi with 120 ml weekly over a 7-month growth period, and vice versa. Plant height, plant diameter, number of leaves, leaf area, chlorophyll content, total root length, number of root tips, root diameter, root surface area, root volume, shoot dry weight, root …

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Augmentation Of The Differentiation Response To Antitumor Quinolines, Rayhana Rahim-Bata Dec 2004

Augmentation Of The Differentiation Response To Antitumor Quinolines, Rayhana Rahim-Bata

Graduate Theses, Dissertations, and Problem Reports (ETD)

An impeding challenge to breast cancer drug therapies is the availability of more effective and less toxic chemotherapeutic agents that do not relay harm to neighboring normal breast cells and tissues. Preliminary studies showed that the quinoline antimalarials, chloroquine (CQ and hydroxychloroquine (HCQ), inhibit proliferation and induce differentiation in breast cancer cell lines without toxicity to normal MCF-10A breast cells. Hence, the goal of these studies was to explore: (1) whether a drug combination modulating epigenetic events would sensitize breast cancer cells to the antitumor activity of CQ or HCQ, (2) and if so, which would be the most promising …

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Sensitivity To Molar Contingencies Of Food Presentation, Jeffrey Everly Dec 2004

Sensitivity To Molar Contingencies Of Food Presentation, Jeffrey Everly

Graduate Theses, Dissertations, and Problem Reports (ETD)

Twelve rats were exposed to two variable-time schedules that differed in their rates of food delivery. The "imposed" schedule was normally in effect, but lever pressing occasionally switched to the "alternate" schedule for periods averaging 30 s. Increases in food frequency afforded by switching to the alternate schedule were manipulated across conditions. All rats were exposed to the same absolute food frequency increases, but the programming of these increases was varied among the rats by holding particular food delivery rates constant across conditions. For half of the rats, the schedules were signaled. In general, response rates were directly related to …

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Managing Classroom Behavior Of Head Start Children Using Response Cost And Token Economy Procedures, Jennifer D. Tiano Dec 2004

Managing Classroom Behavior Of Head Start Children Using Response Cost And Token Economy Procedures, Jennifer D. Tiano

Graduate Theses, Dissertations, and Problem Reports (ETD)

The efficacy of three behavior management techniques used in a Head Start classroom was examined. The three techniques included: (a) techniques currently used by the teacher, (b) response cost, and (c) the Level System (token economy). The current study used an ABACA single subject withdrawal design with follow-up where all conditions were implemented until stability was reached. Classroom behavior was evaluated by both behavioral observation and teacher report. Children's behavior, teacher skill, number of time-outs, and satisfaction with behavior management techniques (i.e., teacher, parent, and child) were examined. No conclusions could be made concerning the efficacy (i.e., inappropriate behavior, class …

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Geotechnical Investigation Of Montrose Wetland Site, Christopher R. Ryan Dec 2004

Geotechnical Investigation Of Montrose Wetland Site, Christopher R. Ryan

Graduate Theses, Dissertations, and Problem Reports (ETD)

The purpose of this investigation is to obtain the geotechnical characteristics of the site and to aid in the creation of a proposed engineered wetland at Montrose, West Virginia. The tests performed in the laboratory to obtain the soil properties were: water content, Atterberg limits (liquid and plastic limits), grain size (sieve analysis and hydrometer), specific gravity, field density, and hydraulic conductivity. Tests were performed on soil samples taken from the site during installation of monitoring wells. Results from tests were used in the classification of soil. Additional samples were reconstructed to determine the permeability of the soil. These tests …

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Real-Time Video Compression Using Dvq And Suffix Trees, Pavan Kumar Vedantam Dec 2004

Real-Time Video Compression Using Dvq And Suffix Trees, Pavan Kumar Vedantam

Graduate Theses, Dissertations, and Problem Reports (ETD)

Video processing is a wide and varied subject area. Video compression is an important but difficult problem in video processing. Several methods and standards exist which address this problem with varying degrees of success depending on the performance measures adopted. The present research work focuses on the real-time aspect of video processing.;In particular we propose a real-time video compression algorithm based on the concept of differential vector quantization and the suffix tree. Differential vector quantization is a relatively new area that focuses on efficient compression of data. The present work integrates the compression provided by Differential vector Quantization and the …

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Reasons For Overwinter Declines In Age-1+ Brook Trout Populations (Salvelinus Fontinalis) In Appalachian Headwater Streams, Jeremy J. Webster Dec 2004

Reasons For Overwinter Declines In Age-1+ Brook Trout Populations (Salvelinus Fontinalis) In Appalachian Headwater Streams, Jeremy J. Webster

Graduate Theses, Dissertations, and Problem Reports (ETD)

Brook trout (Salvelinus fontinalis) in the Appalachian Mountains are an important game species in West Virginia, yet angling mortality on these populations in headwater streams is poorly understood. The objectives of this study were to: (1) examine relative changes in body composition of brook trout as they fluctuate throughout the year, and to identify critical periods of survival to determine if brook trout reach critical levels of resource depletion over winter, and (2) evaluate whether angler harvest affects brook trout populations in spring in headwater streams. Body composition estimates indicated that brook trout are unlikely to reach critical levels of …

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Constraint-Based Facilities Planning, Tafazzul Ahmed Khan Dec 2004

Constraint-Based Facilities Planning, Tafazzul Ahmed Khan

Graduate Theses, Dissertations, and Problem Reports (ETD)

In recent years a large variation of production volume for the mass-production products happens frequently due to the changes in technology and market. Those changes cause introduction of new products having shorter life cycles, thus enforcing modification and renewal of production facilities much earlier than their lifetime. A model was built to assess the impact of manufacturing parameters on the effectiveness of the layout and the material handling system. A relationship was developed between variations in production oriented parameters and its impact on the facility size and final cost of the product being manufactured exclusively in terms of machine time, …

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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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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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Numerical Simulation Of Fine Particle Separation In Hindered -Settling Bed Separators By Computational Fluid Dynamics, Yunkai Xia Aug 2004

Numerical Simulation Of Fine Particle Separation In Hindered -Settling Bed Separators By Computational Fluid Dynamics, Yunkai Xia

Graduate Theses, Dissertations, and Problem Reports (ETD)

The objective of the present study was to improve the understanding of multiple phase flows in hindered-settling bed separators (HSBS). A better understanding of mineral separation in HSBS and the role of structured plates was gained through studies conducted with Computational Fluid Dynamics (CFD) analysis tools. An Euler-Lagrange model from CFD technique is used for this purpose.;In an Euler-Lagrange model, two dimensional incompressible Navier-Stokes equations are solved with the implementation of a finite volume approach over staggered grids with application of Baldwin-Lomax turbulent model. The overall accuracy of the method is second-order in both space and time. The calculation of …

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Effects Of Various Phytase Concentrations In Diets With Low-Phytate Corn On Broiler Chick Performance And Metabolism, Nicole J. Baker Aug 2004

Effects Of Various Phytase Concentrations In Diets With Low-Phytate Corn On Broiler Chick Performance And Metabolism, Nicole J. Baker

Graduate Theses, Dissertations, and Problem Reports (ETD)

Research indicates a reduction of phosphorus content in fecal excreta with the supplementation of phytase to corn-soybean meal based diets or with the use of low phytate corn (LPC) in broilers. This study examined how 0--3 wk broiler chicks are impacted by concomitant phytase supplementation with LPC (0.136% phytate phosphorus (PP) by analysis) in the diet. Various levels of phytase from either 2500 or 5000 FYT/g of Peniophora lycii phytase product were used as experimental treatments. Efficacy of treatments was determined using a response curve created with increasing levels of monocalcium phosphate. Following a 6-day pretest, 576 broiler chicks were …

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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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Psychophysical Studies Of Binocular And Spatial Vision In Humans With Anisometropic And Strabismic Amblyopia, Ritwick Agrawal Aug 2004

Psychophysical Studies Of Binocular And Spatial Vision In Humans With Anisometropic And Strabismic Amblyopia, Ritwick Agrawal

Graduate Theses, Dissertations, and Problem Reports (ETD)

Amblyopia is a common developmental visual disorder. Previous studies of amblyopia have delineated spatial and binocular deficits. However debate exists about how the strabismic and anisometropic subtypes may differ. The central hypothesis is that the two subtypes differ with regard to binocular integration functions. Strabismic subjects may show severe impairments of binocular integration due to a history inter-ocular suppression, which predicts the pattern of monocular deficits. Seven anisometropic, six strabismic and seven control subjects were tested psychophysically with four monocular tests and three binocular tests. Results indicated that the degree of loss of Vernier acuity was larger than that predicted …

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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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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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Recruitment Strategies Used By High School Agriculture Education Teachers In West Virginia, Danny R. Dewhurst Aug 2004

Recruitment Strategies Used By High School Agriculture Education Teachers In West Virginia, Danny R. Dewhurst

Graduate Theses, Dissertations, and Problem Reports (ETD)

Recruitment is the act of enrolling new members as well as keeping current levels of members or students. Questionnaires were sent to all agricultural education teachers in West Virginia to determine what strategies were being used to maintain and increase enrollment in agriculture education programs throughout West Virginia. The first questionnaire was sent to 97 agricultural education teachers asking them to list recruiting activities that they used to promote their programs. A second questionnaire was sent asking them to rate the effectiveness of recruitment activities they have participated in over the past four (4) years. Forty-six secondary agricultural education teachers …

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Effect Of Grain Particle Size, Feed Form And Pellet Texture On Broiler Performance, Carcass Quality, True Metabolizable Energy, Feed Passage Time And Preference, Amy S. Parsons Aug 2004

Effect Of Grain Particle Size, Feed Form And Pellet Texture On Broiler Performance, Carcass Quality, True Metabolizable Energy, Feed Passage Time And Preference, Amy S. Parsons

Graduate Theses, Dissertations, and Problem Reports (ETD)

Treatments consisted of five mash diets (781 microns, 950 microns, 1,042 microns, 1,109 microns, 2,242 microns) and two pelleted diets (water (soft) and binder (hard) inclusion). Water and binder addition produced similar pellet durability (90.4% and 86.2% respectively) and fines (44.5% and 40.3% respectively).;Broilers fed mash diets exhibited decreased live weight gain and breast yield with increased gizzard, compared to broilers fed pelleted diets. As diet particle size increased, feed intake and gizzard yield increased and feed efficiency decreased. Broiler true metabolizable energy increased then decreased when diet particle size increased. Hard pellets increased live weight gain. Fines of the …

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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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Operant Conditioning In Older Adults With Alzheimer's Disease, Adam P. Spira Aug 2004

Operant Conditioning In Older Adults With Alzheimer's Disease, Adam P. Spira

Graduate Theses, Dissertations, and Problem Reports (ETD)

Behavioral interventions are commonly implemented to manage agitation in older adults with dementia. However, the extent to which operant conditioning can occur in this population is unclear. The present study used a button-pressing task to evaluate the sensitivity of the responding of individuals with probable Alzheimer's disease to changes in schedules of reinforcement. Results indicate that operant conditioning can occur in older adults with AD. Specifically, three participants with AD exhibited responding that was highly sensitive to a transition from a fixed interval schedule to an extinction schedule. One participant's responding was sensitive to a more subtle transition. Comparison data …

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Reduction Of Natural Gas Engine Emissions Using A Novel Aftertreatment System, Timothy S. Burlingame Aug 2004

Reduction Of Natural Gas Engine Emissions Using A Novel Aftertreatment System, Timothy S. Burlingame

Graduate Theses, Dissertations, and Problem Reports (ETD)

The global objective of this study was to develop an exhaust aftertreatment system to reduce gaseous and particulate matter emissions from natural gas fueled vehicles. Specific objectives of this study were to evaluate and characterize emissions from a natural gas fueled vehicle powered by a Cummins C8.3G+ engine with and without the particulate matter (PM) filter and oxidation catalyst (OC) combination, which was designed and developed by West Virginia University in collaboration with Lubrizol-ECS. Central Business District (CBD) Cycle tests were performed on West Virginia University's Transportable Emissions Testing Laboratory. A heavy-duty transportable chassis dynamometer and a dedicated "clean" dilution …

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Hydrologic Investigation Of Three Constructed Mitigation Wetlands And One Natural Wetland In West Virginia, Scott A. Copen Aug 2004

Hydrologic Investigation Of Three Constructed Mitigation Wetlands And One Natural Wetland In West Virginia, Scott A. Copen

Graduate Theses, Dissertations, and Problem Reports (ETD)

The goal of this study was to increase the probability of success for future mitigation wetland projects by performing a hydrologic investigation at three constructed mitigation wetland sites and one natural reference wetland site. In addition, a numerical groundwater model was developed for a portion of one of the constructed mitigation wetlands.;Hydrologic, meteorologic, topographic, and geotechnical data were collected at three constructed mitigation wetlands and one reference natural wetland. Hydrologic data were collected using monitoring wells, piezometers, automated water level recorders, and a water level meter. Meteorologic data were obtained from the National Oceanic and Atmospheric Administration's weather station in …

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Failure Mechanisms In Impact Erosion Of Ductile Materials, Ramesh Padavala Aug 2004

Failure Mechanisms In Impact Erosion Of Ductile Materials, Ramesh Padavala

Graduate Theses, Dissertations, and Problem Reports (ETD)

Solid particle erosion in ductile materials is a common problem in many industrial applications. It is defined as material loss resulting from the mechanical contact between the particle and the metal surface. Many experimental studies were reported in the past to determine the loss of the material due to these ductile impacts. Conducting experiments for numerous materials at different conditions is difficult and costly. A finite element model to predict the ductile erosion loss at various conditions for different materials is more expedient.;In this thesis a finite element model was developed to predict the erosion loss for AL 6061-T0 at …

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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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