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The Role Of Reactive Oxygen Species And Pi3k /Akt Signaling In Tumor Angiogenesis., Chang Xia Jan 2006

The Role Of Reactive Oxygen Species And Pi3k /Akt Signaling In Tumor Angiogenesis., Chang Xia

Graduate Theses, Dissertations, and Problem Reports (ETD)

Tumor angiogenesis is the development of vascularization from pre-existing vessels. It provides the tumors with sufficient nutrients and enables them to break the dormancy. Due to the imbalance of positive and negative angiogenic regulation, tumor blood vessels are usually leaky and chaotic which create accessible avenue for tumor metastasis. Phosphatidylinositol-3-kinases (PI3Ks) are lipid kinases that generate phospholipid second messengers and mediate signal transduction. Mutations of PI3Ks and constitutive activation of PI3K/AKT signaling have been frequently found in many human cancers. Reactive oxygen species are also important second messengers in various physiological and pathological processes, including tumor formation and metastasis and …

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A Strategy For Prevention Of Sequestered Carbon Dioxide Seepage From Cbm Formations., Miguel Angel Tovar Torrealba Jan 2006

A Strategy For Prevention Of Sequestered Carbon Dioxide Seepage From Cbm Formations., Miguel Angel Tovar Torrealba

Graduate Theses, Dissertations, and Problem Reports (ETD)

This study introduces a new strategy for the prevention of post-sequestration carbon dioxide (CO2) seepage to the surface from CBM (coalbed methane) formations that is named the “N ature’s Sequestration Technique” or “N ST.” The objective is to sequester CO2 in a CBM formation for an extensive time period (thousands of years), filling the coal cleat system with formation water. Using a commercial numerical simulator and representative data of the Appalachian basin, we investigated whether or not the presence of water in the cleats helps to sequester CO2 in a coalbed for a long period of time without significant seepage. …

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Error Resilient Transmission Of Three-Dimensional Dct Coded Video., Supriya Dilip Sawant Jan 2006

Error Resilient Transmission Of Three-Dimensional Dct Coded Video., Supriya Dilip Sawant

Graduate Theses, Dissertations, and Problem Reports (ETD)

Current multimedia applications involve video transmission over unprotected noisy channels where the video stream is contaminated with errors thereby requiring advanced error concealment/correction strategies. Our objective in this research is to devise error resilient strategies that will help combat channel errors and produce a quality video reconstruction. In this thesis we investigate two error resilient techniques, namely, unequal error protection (UEP) and multiple description coding (MDC) for video transmission. Unlike the traditional video coding system that uses two dimensional transformations accompanied with motion estimation and compensation, we focus on the three dimensional discrete cosine transform (3D DCT). We propose video …

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Perceived Constraints And Negotiation Strategies Of Ethnic/Racial Minorities As Predictors Of Recreation Participation., Elizabeth A. Covelli Jan 2006

Perceived Constraints And Negotiation Strategies Of Ethnic/Racial Minorities As Predictors Of Recreation Participation., Elizabeth A. Covelli

Graduate Theses, Dissertations, and Problem Reports (ETD)

The purpose of this study was to investigate the constraints that non-traditional users face, along with the negotiation strategies that are employed in order to start, continue or increase participation when trying to recreate on a national forest. Nontraditional users were defined as respondents who were not Caucasian. Additionally, both constraints and negotiation strategies were examined to see if they predict participation for non-traditional users. The study took place on the Mt. Baker-Snoqualmie National Forest in Washington, during the summer of 2005. A quantitative survey method was used, with a total of 235 surveys collected. The results showed that over …

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Characterization Of A Catalase Gene Associated With Ergot Alkaloids In Aspergillus Fumigatus, And, Studies On An Alternate Lysergyl Peptide Synthetase Gene And Ergopeptine In Neotyphodium Coenophialum., Kerry E. Goetz Jan 2006

Characterization Of A Catalase Gene Associated With Ergot Alkaloids In Aspergillus Fumigatus, And, Studies On An Alternate Lysergyl Peptide Synthetase Gene And Ergopeptine In Neotyphodium Coenophialum., Kerry E. Goetz

Graduate Theses, Dissertations, and Problem Reports (ETD)

Ergot alkaloids, a category of mycotoxins produced by various fungi, adversely affect both humans and animals. Several plant-associated fungi in the genera Claviceps, Neotyphodium, and Epichloe (order Hypocreales) produce an array of ergot alkaloids. Another fungus, Aspergillus fumigatus that occupies a completely different ecological niche and is classified under the order Eurotiales, also produces ergot alkaloids. The gene clusters predicted to encode the enzymes required for ergot alkaloid production within these species are strikingly similar, however, they are poorly understood. In this study, a gene knockout of the easC gene that encodes a putative catalase resulted in the loss of …

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"Mirror Worlds": Transpacific Inspiration And Mimetic Rivalry In American And East Asian Literature, 1945-2005., Matthew J. Packer Jan 2006

"Mirror Worlds": Transpacific Inspiration And Mimetic Rivalry In American And East Asian Literature, 1945-2005., Matthew J. Packer

Graduate Theses, Dissertations, and Problem Reports (ETD)

One conspicuous trend during the world economy's shift to the Pacific Rim in the late twentieth century has been the increased reciprocal inspiration and mimetic rivalry between American and East Asian cultures. For much of the past century, for example, the Japanese have been stereotyped as cultural copycats, when transpacific imitating actually has been mutual: as East Asians have looked to the West for models of development and the imagination, so have Americans looked to the Far East---as even representing the future, according to novelist William Gibson. Americans have drawn inspiration from Eastern aesthetics, while East Asians have copied Western …

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De Novo Asymmetric Syntheses Of Biologically Important Natural Products: Phomopsolide D, Phomopsolide E, Milbemycin Beta3 And Apicularen A., Miaosheng Li Jan 2006

De Novo Asymmetric Syntheses Of Biologically Important Natural Products: Phomopsolide D, Phomopsolide E, Milbemycin Beta3 And Apicularen A., Miaosheng Li

Graduate Theses, Dissertations, and Problem Reports (ETD)

De novo asymmetric synthesis is a strategy that uses asymmetric catalysis to construct chiral molecules from achiral starting materials. One of the advantages of this strategy is that we can synthesize numerous stereoisomers (e.g. the enantiomers) of the target natural product for biological testing. Substituted α,β-unsaturated δ-lactones are an important class of natural products with a wide range of biological activity. Many synthetic methodologies have been developed to synthesize this core structure. However, they depended on either performing kinetic resolutions or chiral starting materials (e.g. carbohydrates). We envisioned using catalytic asymmetric catalysis (de novo approach) to synthesize these complex molecules. …

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George Eliot And The Anxious Construction Of The Domestic Other: Racial Inheritance, Radical Femininity And Masculinity, And National Identity In "The Spanish Gypsy" And "Daniel Deronda"., Christina E. Godlewski Jan 2006

George Eliot And The Anxious Construction Of The Domestic Other: Racial Inheritance, Radical Femininity And Masculinity, And National Identity In "The Spanish Gypsy" And "Daniel Deronda"., Christina E. Godlewski

Graduate Theses, Dissertations, and Problem Reports (ETD)

This dissertation seeks to articulate the extent to which George Eliot engages in an active dialogue with contemporary scientific thought, particularly in respect to England's Jewish and Gypsy populations. I examine The Spanish Gypsy and Daniel Deronda to determine Eliot's position in relation to ideologies on race, gender, and class. Eliot's texts manage to expose some of the contradictions regarding these two "domestic others" within the dominant discourses of the Victorian period. Chapter one sets out my critical and methodological framework and foregrounds the discursive proximity between the Gypsies, the Jews, the working classes, and women in the Victorian period. …

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Hepatic Α-Aminoadipate Δ-Semialdehyde Synthase Appears To Be Post-Translationally Regulated In Mouse And Chicken., Aaron S. Kiess Jan 2006

Hepatic Α-Aminoadipate Δ-Semialdehyde Synthase Appears To Be Post-Translationally Regulated In Mouse And Chicken., Aaron S. Kiess

Graduate Theses, Dissertations, and Problem Reports (ETD)

 Lysine is the limiting amino acid in many animal diets. Improving the efficiency of lysine use for protein synthesis can reduce feed cost and potentially the nitrogen and phosphorus output of agricultural production systems. Lysine not used for protein synthesis is oxidized, primarily by lysine α-ketoglutarate reductase (LKR). The mechanism(s) responsible for alterations in hepatic LKR activity in rodents and poultry are still unclear. For this reason, studies in both species were conducted to evaluate possible mechanisms responsible for alterations of LKR activity. Mice were fed either a high or adequate protein diet. Mice fed the high protein diet had …

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Surrendered Resistance: Playing Dead In American Autobiographical Writing, 1840-1933., Georgia R. Kreiger Jan 2006

Surrendered Resistance: Playing Dead In American Autobiographical Writing, 1840-1933., Georgia R. Kreiger

Graduate Theses, Dissertations, and Problem Reports (ETD)

This dissertation focuses on the use of death as a metaphor for lived experiences in nineteenth- and early twentieth-century American autobiographical writing. Adopting Paul de Man’s definition of autobiography as a figure of reading rather than a genre or mode, the study analyzes autobiographical death acts in a variety of writings, including political discourse, fiction, and poetry. The writers discussed stage deaths-of-the-self to facilitate descriptions of traumatic events that might otherwise defy verbal expression. They “play dead” figuratively in their texts, similarly to the way one might play dead literally as a survival strategy in the presence of an animal …

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Effects Of Various Environmental Parameters On The Reduction Of Arsenic(V) To Arsenic(Iii) By Dissolved Organic Matter., Tsanangurayi Tongesayi Jan 2006

Effects Of Various Environmental Parameters On The Reduction Of Arsenic(V) To Arsenic(Iii) By Dissolved Organic Matter., Tsanangurayi Tongesayi

Graduate Theses, Dissertations, and Problem Reports (ETD)

The objective of this study was to investigate the reduction of inorganic As(V) with Suwannee River fulvic acid (FA) in aqueous solutions and in real samples. Samples of inorganic As(V) were incubated with FA under various solution conditions and aliquots from the incubated samples were taken at various time intervals and analyzed for As(III) using square wave cathodic stripping voltammetry at a hanging mercury drop electrode. The study demonstrated the following important aspects of As speciation: (1) FA can significantly reduce As(V) to As(III), (2) Reduction of As(V) to As(III) is a function of pH, (3) Reduction of As(V) to …

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Sarah Livingston Jay, 1756--1802: Dynamics Of Power, Privilege And Prestige In The Revolutionary Era, Jennifer Megan Janson Dec 2005

Sarah Livingston Jay, 1756--1802: Dynamics Of Power, Privilege And Prestige In The Revolutionary Era, Jennifer Megan Janson

Graduate Theses, Dissertations, and Problem Reports (ETD)

Sarah Livingston Jay was a politically astute woman whose contributions to the success of the American Revolution and reconstruction of post-war society have long been underestimated. She understood the complex political and financial dynamics beneath the decision to declare independence from Great Britain and the international alliances necessary for success. Intelligent, educated and socially skilled, she used her personal gifts, position, and familial connections to exert a strong influence on the course of events that would benefit her fledgling country. She used her social graces to take part in the male-dominated political world, while working within the domestic realm. She …

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Organic Poultry Production And Forage Digestibility, Nancy P. Buchanan Dec 2005

Organic Poultry Production And Forage Digestibility, Nancy P. Buchanan

Graduate Theses, Dissertations, and Problem Reports (ETD)

The current experiments were conducted to evaluate organic poultry production and the digestibility of organic feeds and pasture forages. A performance study was conducted to determine the effect of exogenous non-starch polysaccharide (NSP) enzyme supplementation on the performance and carcass characteristics of organically-reared broiler chickens. The addition of an exogenous NSP enzyme cocktail improved the performance and carcass characteristics of organically-reared broilers given access to pasture only in spring months. Pasture forages may contribute digestible nutrients to poultry; however, this contribution has not been evaluated in past research. A digestibility study was conducted to determine the nitrogen-corrected apparent metabolizable energy …

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Implications For The Small Mammal And Earthworm Communities In A Degraded Ecosystem, Jennifer Aaron Edalgo Dec 2005

Implications For The Small Mammal And Earthworm Communities In A Degraded Ecosystem, Jennifer Aaron Edalgo

Graduate Theses, Dissertations, and Problem Reports (ETD)

At Fort Necessity National Battlefield, Pennsylvania, we trapped small mammals in areas dominated by Morrow's honeysuckle, an invasive shrub, and we determined that prebaiting 1 and 2 days before the actual trapping period did not improve trapping success. We do not recommend using the added resources (i.e., time, money, personnel, and equipment) to incorporate prebaiting into trapping regimes because trapping success was not improved. We fluorescent powdertracked mice in old field and forested areas with Morrow's honeysuckle encroachment to determine the microhabitat they selected. Mice selected paths with high shrub and tree cover and low herbaceous cover. They selected native …

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Nesting Success And Nest Site Characteristics Of Four Thrush Species On A Managed Forest, Rachel Dellinger Dec 2005

Nesting Success And Nest Site Characteristics Of Four Thrush Species On A Managed Forest, Rachel Dellinger

Graduate Theses, Dissertations, and Problem Reports (ETD)

Four thrush species breed sympatrically in the Allegheny Mountain region of West Virginia, U.S.A.: American Robin (Turdus migratorius), Hermit Thrush (Catharus guttatus), Veery (Catharus fuscescens), and Wood Thrush (Hylocichla mustelina). How nesting habitat is partitioned among the species is unclear, as is the effect of logging activities on the guild. My objectives were to identify nesting habitat characteristics that are partitioned among the species and to determine their effects on nest survival.;I conducted point count surveys and monitored nests of four thrush species on a managed forest. I measured habitat variables at three scales: (1) nest substrate, (2) nest site, …

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Temporal Trends In Consumption, Growth, And Successful Feeding Traits Of A Central Appalachian Brook Trout Population At The Watershed Scale, Ryan Michael Utz Dec 2005

Temporal Trends In Consumption, Growth, And Successful Feeding Traits Of A Central Appalachian Brook Trout Population At The Watershed Scale, Ryan Michael Utz

Graduate Theses, Dissertations, and Problem Reports (ETD)

Brook trout (Salvelinus fontinalis) in Appalachia frequently experience limitations in food availability. In order to determine temporal variation in consumption, successful feeding, and corresponding population patterns and growth, the feeding dynamics of a population of brook trout were monitored throughout a headwater watershed over the course of two years. The Middle Fork River brook trout experienced food limitation throughout summer and fall, however, mean consumption estimates fell below maintenance ration only during the winter seasons. Consumption estimates were significantly related to watershed position, as fish in low density, downstream reaches consistently consumed significantly more energy than fish upstream during warm …

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Production Of Conjunctions And T-Units By The Elderly, Benjamin Haymond Dec 2005

Production Of Conjunctions And T-Units By The Elderly, Benjamin Haymond

Graduate Theses, Dissertations, and Problem Reports (ETD)

Recent research indicates a change in healthy elderly adult language capabilities. More specifically, Shadden (1997) and Ryan (1996) state that language competence is less affected by the processes of aging than production. The topic of this research examined specifically the production of conjunctions from the perspective of Halliday and Hasan (1976) in procedural and narrative discourse by the elderly. The hypothesis stated that the relationship between age and conjunctions produced would be non-significant. In a cross-sectional study, 17 subjects between the ages of 60-86 were interviewed and the transcripts analyzed.;Results supported the hypothesis of a non-significant relationship between age and …

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Ozone Forming Potential Of Exhaust Emissions From Heavy-Duty Diesel Engines, Ravi Kaklasaria Dec 2005

Ozone Forming Potential Of Exhaust Emissions From Heavy-Duty Diesel Engines, Ravi Kaklasaria

Graduate Theses, Dissertations, and Problem Reports (ETD)

This research aimed at determining the effect of exhaust aftertreatment devices and ultra low sulfur diesel (ULSD) fuel on the reactivity of exhaust emissions from heavy duty diesel (HDD) engines. Specifically, the objective of this research was to determine the effect of two diesel particulate filters: Engelhard DPX(TM) and Johnson Matthey CRT(TM), and two ULSD fuels, ECD and ECD1 on the ozone forming potential (OFP) of exhaust emissions from HDD engines. To achieve this objective, data was obtained from the "ECD Study" performed in the Spring 2001 to chemically characterize emissions from trucks and buses operating on the two test …

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A Detailed Sequential Extraction Study Of Selenium In Coal And Coal-Associated Strata From A Coal Mine In West Virginia, Mimi Roy Dec 2005

A Detailed Sequential Extraction Study Of Selenium In Coal And Coal-Associated Strata From A Coal Mine In West Virginia, Mimi Roy

Graduate Theses, Dissertations, and Problem Reports (ETD)

This study of the mode of occurrence and distribution of selenium in a rock core from southcentral West Virginia reveals that total selenium concentration varies by rock type. Rocks with total selenium >1 mg/kg were of circum-neutral pH based on acid base accounting data. No direct correlation was found between selenium concentration in the rocks and that of sulfur and/or total organic carbon. The distribution of total selenium was also controlled by stratigraphy. The amount of total selenium extracted from various rock types like coal, shale, sandstone, mudstone and "carbolith" materials ranged from 50%. Selenium extracted from coal was mostly …

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Action Research Analysis Of The Forces Affecting Farmer Participation In A West Virginia Cooperative Extension Service Farmer Education Program, John Robert Edalgo Dec 2005

Action Research Analysis Of The Forces Affecting Farmer Participation In A West Virginia Cooperative Extension Service Farmer Education Program, John Robert Edalgo

Graduate Theses, Dissertations, and Problem Reports (ETD)

This study uses action research principles and Kurt Lewin's field theory to investigate the forces dictating farmer participation in the Decision Enabling Data Collection and Management System Initiative (DEDCMSI). These forces were classified in Chapter IV under the following project categories: Hardware, Software, Perception of DEDCMSI, Perception of Technology, and Sociocultural. This West Virginia University Cooperative Extension Service (WVUCES) initiative organized four farm finance groups located in the following counties: Ohio, Jefferson, Mineral, and Monroe. Data collection methods used to identify forces occurring within this seven-month pilot project is listed here as follows: structured, semi-structured, and un-structured interviews. A total …

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Cellular Mechanisms Of Luteal Regression In The Bovine Corpus Luteum (Cl), Aritro Sen Dec 2005

Cellular Mechanisms Of Luteal Regression In The Bovine Corpus Luteum (Cl), Aritro Sen

Graduate Theses, Dissertations, and Problem Reports (ETD)

The corpus luteum (CL) is a transient endocrine gland that produces progesterone (P4) for the establishment and maintenance of pregnancy. In absence of pregnancy, timely regression of the CL is essential for normal ovarian cyclicity. Several factors are known to participate in luteal regression. In this study, two factors, PGF2 alpha and endothelin (ET-1) are being studied. Protein kinase C (PKC) and calcium are the two main intracellular mediators of PGF2 alpha. The role of ET-1 in the regulation of luteal regression is unclear. The early CL is insensitive to the luteolytic actions of PGF2 alpha and the cellular mechanism(s) …

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Assessing The Effectiveness Of Descriptive And Experimental Analyses To Identify Variables Influencing Problem Behavior In Domestic Dogs, Susan D. Kapla Dec 2005

Assessing The Effectiveness Of Descriptive And Experimental Analyses To Identify Variables Influencing Problem Behavior In Domestic Dogs, Susan D. Kapla

Graduate Theses, Dissertations, and Problem Reports (ETD)

Problem behavior in dogs is a concern for pet owners. Many contemporary approaches to intervention first involve a process of diagnosis and classification which is often structural in nature. An accurate diagnosis is considered essential for effective treatment, however, outcome data validating the efficacy of this procedure are dubious. The success of strategies used to assess and treat behavior problems that identify behavioral function in humans (functional assessment), however, suggests the potential utility of such techniques in the assessment and treatment of behavior problems in dogs. Therefore, two separate assessments were conducted to identify and manipulate variables affecting problem behavior …

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The Design, Construction And "Optimization" Of A Binder Pitch Refining Unit, Kevin D. Whiteman Dec 2005

The Design, Construction And "Optimization" Of A Binder Pitch Refining Unit, Kevin D. Whiteman

Graduate Theses, Dissertations, and Problem Reports (ETD)

Pitches have been important to mankind for hundreds of years. One of the most important pitches used in industry today is binder pitch. Binder pitch is used to make anodes for the aluminum industry. The supply of high quality binder pitch has been steadily decreasing. A process has been developed to produce binder pitch from coal at West Virginia University, but this pitch in this process requires refining.;The focus of this thesis was to design, and construct a bench top wiped film evaporator system to refine that pitch. From the data collected in this thesis, the process was scaled up …

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Learner Satisfaction And Learning Performance In Online Courses On Bioterrorism And Weapons Of Mass Destruction, Tatiana I. Solovieva Dec 2005

Learner Satisfaction And Learning Performance In Online Courses On Bioterrorism And Weapons Of Mass Destruction, Tatiana I. Solovieva

Graduate Theses, Dissertations, and Problem Reports (ETD)

This study examined the relationships between measures of (a) learner satisfaction with online courses on weapons of mass destruction (WMD) and bioterrorism intended to address the educational needs of responder Communities of Practice (CoP) and (b) degrees of accomplishment by the learner with those online courses. Provided that course design characteristics were similar between courses and that content was different, it was important to examine learner satisfaction with course common aspects in relation to learning outcomes and identify the predictors of effectiveness and relations between the learner satisfaction with the course characteristics and the learner achievement for potential design improvements …

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Multiagent Autonomous Energy Management, Shilpa B. Ganesh Dec 2005

Multiagent Autonomous Energy Management, Shilpa B. Ganesh

Graduate Theses, Dissertations, and Problem Reports (ETD)

The objective of this thesis is to design distributed software agents for reliable operation of integrated electric power systems of modern electric warships. The automatic reconfiguration of electric shipboard power systems is an important step toward improved fight-through and self-healing capabilities of naval warships. The improvements are conceptualized by redesigning the electric power system and its controls. This research focuses on a new scheme for an energy management system in the form of distributed control/software agents. Multiagent systems provide an ideal level of abstraction for modeling complex applications where distributed and heterogeneous entities need to cooperate to achieve a common …

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Culvert Inventory And Effects On Fish Assemblages In A Central Appalachian Watershed, Ira O. Poplar-Jeffers Dec 2005

Culvert Inventory And Effects On Fish Assemblages In A Central Appalachian Watershed, Ira O. Poplar-Jeffers

Graduate Theses, Dissertations, and Problem Reports (ETD)

We surveyed 120 state-owned culverts within the upper Cheat River basin, West Virginia, and used a fish passage evaluation filter to quantify passage barriers. We quantified the length of stream and weighted potential brook trout recruitment area isolated by each culvert. We also sampled fish communities upstream and downstream of 24 culverts to quantify the impacts of culvert-related isolation on fish assemblages. We found 69% of culverts to be completely impassable. We determined that 17% of the stream length and 23% of weighted potential recruitment area in the study area were isolated by impassable culverts. We found that impassable culverts …

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Functional Evaluation Of Cytochrome P450 2d6 Allelic Isoforms, Weiyan Zhang Dec 2005

Functional Evaluation Of Cytochrome P450 2d6 Allelic Isoforms, Weiyan Zhang

Graduate Theses, Dissertations, and Problem Reports (ETD)

Human CYP2D6 is one of the most important human P450s based on the number of its drug substrates. It shows an extensive genetic polymorphism that influences its expression and function. There are more than 80 different CYP2D6 alleles and allelic variants that have been identified in human. However, only a part of alleles have been characterized with respect to enzyme activity and substrate specificity. In the first project, three alleles CYP2D6*24 (1297L), CYP2D6*27 (E410K) and CYP2D6*26 (I369T) were constructed and expressed. The enzymatic activities were evaluated by the metabolic rates for dextromethorphan O-demethylation and N-demethylation; codeine O-demethylation and N-demethylation. For …

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Factors Affecting Reproductive Efficiency Of Cattle, Melanie J. Starbuck Dec 2005

Factors Affecting Reproductive Efficiency Of Cattle, Melanie J. Starbuck

Graduate Theses, Dissertations, and Problem Reports (ETD)

Four experiments were conducted to evaluate two measures of reproductive efficiency in cattle, conception rate and retention of pregnancy. In experiment I, the relationship between concentrations of progesterone and retention of pregnancy was examined. The corpus luteum (CL) was removed on day 29 of pregnancy in 40 suckled, beef cows, and pregnancy was supported with exogenous progesterone to day 53. Concentrations of progesterone (1.8 +/- 0.1 ng/mL between days 30 and 38), were below those normally recorded for pregnant cows. Retention of pregnancy (77%) was monitored frequently using ultrasonography until day 53 and was negatively associated with age of cow, …

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The Behavioral Functions Of Stimuli Signaling Transitions Across Rich And Lean Schedules Of Reinforcement, Jessica B. Long Dec 2005

The Behavioral Functions Of Stimuli Signaling Transitions Across Rich And Lean Schedules Of Reinforcement, Jessica B. Long

Graduate Theses, Dissertations, and Problem Reports (ETD)

The present experiment was designed to assess whether stimuli correlated with rich and lean fixed-ratio schedule components would function as conditioned reinforcers and conditioned punishers, respectively. Pigeons responded on a mixed schedule with fixed-ratio components leading to large or small food reinforcers. Pecks on either of two observing keys converted the mixed schedule to a multiple schedule by turning on a color associated with the current component. The stimulus consequences of the observing responses were manipulated across conditions. Pecks on one observing key produced the rich stimulus and the lean stimulus whereas pecks on the other observing key produced only …

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The Influence Of Beaver Impoundments On Vegetative Composition, And Modeling Habitat Suitability As A Tool For Wildlife Management And Conservation, Jerry Leanne Bonner Dec 2005

The Influence Of Beaver Impoundments On Vegetative Composition, And Modeling Habitat Suitability As A Tool For Wildlife Management And Conservation, Jerry Leanne Bonner

Graduate Theses, Dissertations, and Problem Reports (ETD)

Beavers (Castor canadensis) can have dramatic effects on vegetative communities through impounding streams and wetlands. These alterations may influence rare plant species where beaver create ponds. We found that the youngest and oldest beaver ponds in Canaan Valley, West Virginia, USA had similar species richness. Rare plant species occurred most in oldest ponds, although no significant differences were detected. Species composition around ponds was found to be different between areas influenced by ponds versus those not affected, creating more obligate wetland communities when influenced by beaver. This information should be incorporated into management decisions when rare plant species conservation is …

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