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Graduate Theses, Dissertations, and Problem Reports (ETD)

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A Model For World Wide Web-Based Asynchronous Laboratory Learning In Engineering Education., Prashanth Kumar Salur Jan 1999

A Model For World Wide Web-Based Asynchronous Laboratory Learning In Engineering Education., Prashanth Kumar Salur

Graduate Theses, Dissertations, and Problem Reports (ETD)

World Wide Web based Asynchronous Learning, a new concept in distance learning is gaining large scale acceptance among a number of universities and has become a basis for project work in various universities, colleges and even business enterprises. Asynchronous means that participants in a discussion need not engage in that discussion at the same time, a method to achieve high degree of interactivity among geographically separated learners independent of time or place. This project aims to develop such an Asynchronous Learning environment for laboratory learning containing interactive exercises with simulation experiences. Interactive exercises have been developed with multiple-choice questions and …

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The Effects Of Land-Use History On Plant Species Diversity And Abundance In Dambo Wetlands In Zimbabwe., Fortune Feresu Shonhiwa Jan 1999

The Effects Of Land-Use History On Plant Species Diversity And Abundance In Dambo Wetlands In Zimbabwe., Fortune Feresu Shonhiwa

Graduate Theses, Dissertations, and Problem Reports (ETD)

Land-use history in Zimbabwe has caused dramatic differences in erosion severity between Commercial and Communal Lands. High population numbers have been found to be positively correlated with the extent of eroded area in Communal Lands. Dambo wetlands are particularly vulnerable to this population pressure as they are isolated wet areas supporting plant growth during the six to eight months of the dry season. In Zimbabwe, they cover 1.3 million hectares of the country. This study examines the plant composition and seed bank of these wetlands and compares vegetation in dambos with contrasting land-use histories, communal versus commercial. Communal Lands are …

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A Study Of Protein Interactions By Electrospray Ionization Mass Spectrometry., Weiling Zhang Jan 1999

A Study Of Protein Interactions By Electrospray Ionization Mass Spectrometry., Weiling Zhang

Graduate Theses, Dissertations, and Problem Reports (ETD)

Electrospray Ionization Mass Spectrometry is gaining recognition as a powerful tool for the study of proteins. It is a “soft” ionization source, which permits the preservation of noncovalent interactions prevailing in biological systems. It is able to form multiply charged ions, which facilitates analyses of very large molecules. The change of the protein conformations can be investigated by charge state distribution shifts in ESI-MS. The noncovalent interactions of proteins with other molecules can also be studied by ESI-MS because these interactions often change the shape of proteins. I examined the effect of various operating parameters on shape of the ESI-MS …

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An Exploration Of The Relationship Of Nonverbal Aggression With Verbal Aggression, Nonverbal Immediacy Assertiveness, And Responsiveness., Jamie Leigh Geiser Jan 1999

An Exploration Of The Relationship Of Nonverbal Aggression With Verbal Aggression, Nonverbal Immediacy Assertiveness, And Responsiveness., Jamie Leigh Geiser

Graduate Theses, Dissertations, and Problem Reports (ETD)

A need to study the nonverbal aspect of aggression is argued because the inclusion of nonverbal aspects within the original conception of verbal aggression suggests that the role of nonverbal cues in the expression of aggression might be stronger than originally thought. To test the potential relationship of nonverbal aggression with other personality variables, a 30-item scale of nonverbal aggression was developed. A study of 179 college students is reported which sought to investigate the possibility that nonverbal aggression is related to verbal aggression, nonverbal immediacy, assertiveness, and responsiveness. Gender differences in nonverbal aggression was also investigated. The results revealed …

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The Effects Of Verbal Aggression Involving Father/Son Dyad On Compliance-Gaining And Affect., Michael Charles Germano Jan 1999

The Effects Of Verbal Aggression Involving Father/Son Dyad On Compliance-Gaining And Affect., Michael Charles Germano

Graduate Theses, Dissertations, and Problem Reports (ETD)

The study examined the relationship between father and son when the father employed verbally aggressive strategies. Further, this study examined the level of affect that the son would have toward their father when such strategies were employed. Finally, this study was designed to examine the compliance level of sons toward their father when verbal aggression was present in their relationship. This study included 162 participants from a large Mid-Atlantic University. The results showed that fathers will gain less compliance from their college-aged sons using verbally aggressive messages. Furthermore, sons will not have a positive affect towards their father when verbal …

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Gene Expression Of Components Of The Calpain System: M-Calpain, μ-Calpain And Calpastatin In Male And Female Broiler Skeletal Muscle., Anitha Cholayil Janardhanan Jan 1999

Gene Expression Of Components Of The Calpain System: M-Calpain, μ-Calpain And Calpastatin In Male And Female Broiler Skeletal Muscle., Anitha Cholayil Janardhanan

Graduate Theses, Dissertations, and Problem Reports (ETD)

Muscle growth is regulated by the balance between the two opposing processes of protein synthesis and protein degradation. The calpain system consisting of two ubiquitous proteolytic enzymes m-calpain, µ-calpain and calpastatin (their endogenous inhibitor) is considered to be the major proteolytic system that catalyzes the initiation of myofibrillar protein degradation in muscle. Gene expression studies of the calpain system were carried out in male and female broiler skeletal muscle from breast (pectoralis), leg (semitendinosus) and wing (brachi) in chickens one week through six weeks of age. The RNA isolated from these tissues was used as template for reverse-transcription to synthesize …

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An Investigation Of Complex Formation By The Drosophila Circadian Clock Protein Double-Time And The Effects Of The Double-TimeS Mutation On Complex Formation., Madhavi Kalive Jan 1999

An Investigation Of Complex Formation By The Drosophila Circadian Clock Protein Double-Time And The Effects Of The Double-TimeS Mutation On Complex Formation., Madhavi Kalive

Graduate Theses, Dissertations, and Problem Reports (ETD)

The double-time ( dbt) gene in Drosophila encodes a protein (DBT) related to casein kinase I.This thesis examines whether DBT associates with other proteins besides PER, and whether the association of DBT might change as a function of time of day and genotype in vivo. DBT binds in vitro to several parts of PER and TIM, and to the N terminal of DBT. At all times of day in vivo, a significant fraction of DBT sediments with a molecular weight greater than that of its monomer. In dbtS flies, DBTS may associate more effectively than wild type DBT with other …

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Using Conventional Wireline Logs To Generate Magnetic Resonance Imaging (Mri) Logs: A Feasibility Study., Mark Robert Richardson Jan 1999

Using Conventional Wireline Logs To Generate Magnetic Resonance Imaging (Mri) Logs: A Feasibility Study., Mark Robert Richardson

Graduate Theses, Dissertations, and Problem Reports (ETD)

Magnetic Resonance Imaging (MRI) is used in logging to provide the log analyst an additional tool in establishing reservoir characteristics. Magnetic Resonance Imaging Logging (MRIL) provides information on the Free Fluid, Irreducible Fluid, Total Porosity, Effective Porosity, and Permeability that is far more accurate than Conventional Wireline Log interpretation, enabling better completion practices that will further enhance total recovery. What this feasibility study seeks to show is that by using Neural Networks, it is possible to generate synthetic MRI Logs using conventional Wireline Log data. This study also demonstrates that this practice is possible in different reservoirs having entirely different …

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Pulmonary Response To Silica: Role Of Apoptosis., Fernando Antonio Suarez Jan 1999

Pulmonary Response To Silica: Role Of Apoptosis., Fernando Antonio Suarez

Graduate Theses, Dissertations, and Problem Reports (ETD)

Occupational exposure to crystalline silica has been associated with lung damage and fibrosis. Although previous studies have demonstrated that silica induces apoptosis both in vitro and in vivo, its role in the pathogenesis of silicosis remains unknown. The purpose of the present study was to: 1) characterize silica-induced apoptosis in vitro; 2) establish a temporal relationship between silica exposure, the induction of apoptosis, and lung inflammation/damage; and 3) investigate the role of apoptosis in the differential susceptibilities of two mouse strains to silica. First, experiments were undertaken to characterize the apoptotic response of rat alveolar macrophages in vitro. Primary alveolar …

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Microstructure And Electron Emission Characterization Of The Initial Stages Of Diamond Growth On Silicon(100)., Vikram Lilo Tolani Jan 1999

Microstructure And Electron Emission Characterization Of The Initial Stages Of Diamond Growth On Silicon(100)., Vikram Lilo Tolani

Graduate Theses, Dissertations, and Problem Reports (ETD)

Atomic force and scanning tunneling microscopes have been used to characterize the microstructure and electron emission properties of diamond films grown on Si(100). In particular, we have focussed on the evolution of these film characteristics as diamond and SiC nucleate on Si(100) at 800°C by reaction with C2H4 gas under 5x10-5torr pressure. Under these conditions, there is possibly a brief period of 2-D layer-by-layer growth, but there is a tendency for the film to rapidly convert to a 3-D growth mode marked by the persistence of small primary nuclei ~400-600Å wide and ~5-6 lattice steps high. The in-air electron emission …

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A Biological Comparison Of Discula Destructiva Isolates From Four Geographic Areas., Patricia Gwen Gundrum Jan 1999

A Biological Comparison Of Discula Destructiva Isolates From Four Geographic Areas., Patricia Gwen Gundrum

Graduate Theses, Dissertations, and Problem Reports (ETD)

A series of biological tests were conducted to ascertain whether differences among isolates of the dogwood anthracnose fungus (Discula destructiva ) could be measured. Discula destructiva isolates were recovered from forty symptomatic eastern flowering dogwood trees growing at four locations in West Virginia and Pennsylvania. Before sampling, each tree was rated for percent foliage infected. Symptomatic leaf and twigs were collected in the summer of 1994 and D. destructiva was isolated from each leaf and twig sample. Isolates were cultured on potato dextrose agar (PDA) medium. Subcultures onto the same medium were made in order to evaluate growth and colony …

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Comparing Moral Values In Gotthold Ephraim Lessing's "Miss Sara Sampson" And Nathaniel Hawthorne's "The Scarlet Letter"., Karsten Dieter Kleine Jan 1999

Comparing Moral Values In Gotthold Ephraim Lessing's "Miss Sara Sampson" And Nathaniel Hawthorne's "The Scarlet Letter"., Karsten Dieter Kleine

Graduate Theses, Dissertations, and Problem Reports (ETD)

This thesis examines the impact of rigid moral codes on women by comparing two works, Lessing’s Miss Sara Sampson, (1775), and Hawthorne’s The Scarlet Letter, (1850). Although the works were written in different centuries and continents, they share a common theme: the clash between patriarchal control and women’s quest for self-determination. In each work, a beautiful young woman violates the social code by becoming involved in an illicit love affair, and because of this transgression and her refusal to renounce her love, is severely punished. Also in each work, the father-daughter relationship is highlighted and can be seen to symbolize …

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Developing Critical Consciousness: Representations Of Race And Gender In Two Afro-German Works., Maren Knebel Jan 1999

Developing Critical Consciousness: Representations Of Race And Gender In Two Afro-German Works., Maren Knebel

Graduate Theses, Dissertations, and Problem Reports (ETD)

Eva Demski and Ika Hügel-Marshall are two contemporary women writers whose works contribute significantly to the Afro-German culture. Demski is a “white” German author who depicts in her novel the life of an Afro-German woman, Afra, as well as the life of her “white” daughter, Nivea. Hügel-Marshall, who was born in 1947 as the daughter of a German mother and an African-American father, depicts in her autobiography her own development from object to subject. This thesis demonstrates that both authors encourage a development of critical consciousness by creating written evidence of a shared Afro-German identity and by expressing the problems …

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The Effects Of Aluminum And Nitrogen On Mycorrhizal And Non-Mycorrhizal Tulip Poplar., Heidi Brauer Lux Jan 1999

The Effects Of Aluminum And Nitrogen On Mycorrhizal And Non-Mycorrhizal Tulip Poplar., Heidi Brauer Lux

Graduate Theses, Dissertations, and Problem Reports (ETD)

Elevated levels of acidic deposition are leading to higher concentrations of aluminum (Al) in the soil solutions of some forest ecosystems. For this thesis, I performed a suite of experiments to investigate the effects of four interconnected factors on the growth and nutrition of Liriodendron tulipifera L. (tulip poplar): 1. Al exposure in solution; 2. mycorrhizal presence and percent colonization; 3. N source ratio; and 4. N level. My studies of L. tulipifera demonstrate a sensitivity to Al at concentrations as low as 100 µM, ranking it among the most Al sensitive tree species ever studied. Selected Al tolerant species …

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Effect Of Maturity And Divalent Salts On Quality Of Low-Fat, Low-Sodium Restructured Beef., Sharon L. Pojedinec Jan 1999

Effect Of Maturity And Divalent Salts On Quality Of Low-Fat, Low-Sodium Restructured Beef., Sharon L. Pojedinec

Graduate Theses, Dissertations, and Problem Reports (ETD)

Manipulation of product formulation protocols and ingredients to optimize texture development and processing yields provides opportunity to produce high quality, low sodium, low-fat restructured beef. The objective of this experiment was to determine effect of preblending with MgCl2 and/or CaCl2 on functionality of A- and C-maturity, in low-sodium, low-fat restructured beef. Addition of CaCl2 decreased (p< 0.001) raw and cooked pH. For both maturities, raw products with CaCl2 had more soluble protein (p< 0.05) than products without CaCl2. C-maturity products contained more soluble myosin (p< 0.10) than A-maturity products. In C-maturity treatments, MgCl2 increased (p< 0.005) myosin solubility. Products with CaCl2 decreased (p< 0.01) actin solubility. In A-maturity products, MgCl2 had less (p< 0.05) soluble actin than treatments without MgCl2. In C-maturity products, MgCl2 contained more (p< 0.05) soluble actin than treatments without MgCl2. Addition of CaCl2 decreased (p< 0.005) cook yield and addition of MgCl2 increased (p< 0.005) cook yield. In C-maturity products, treatments without CaCl2 had a higher (p< 0.0005) peak force than treatments without CaCl2 in A maturity products. In A-maturity products, treatments without MgCl2 had lower (p< 0.005) peak force than the same treatment in C-maturity products and lower (p< 0.05) than MgCl2 containing treatments. C-maturity products were more cohesive (p< 0.08) than A-maturity. Addition of CaCl2 increased (p< 0.05) cohesiveness and added MgCl2 decreased (p< 0.05) cohesiveness. Addition of MgCl2 and CaCl2 and beef maturity affect protein-water interactions and texture development of low-sodium, low-fat restructured beef.

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The Effect Of Diet Dilution With Lactose On The Performance Of Turkeys., Melvin Fungayi Simoyi Jan 1999

The Effect Of Diet Dilution With Lactose On The Performance Of Turkeys., Melvin Fungayi Simoyi

Graduate Theses, Dissertations, and Problem Reports (ETD)

An experiment involving 96 turkeys was carried out in conventional battery cages. The purpose of this experiment was to determine the effect of lactose on the productive performance of turkeys. Another objective was to establish the optimum level of inclusion in the diet. Birds were housed two per cage from day-old to six weeks old. Diets, containing 0, 0.5, 1, 2, 4 and 8% lactose, and water were offered ad libitum throughout the trial. The highest average weight gain per cage (3.79Kg) was recorded in birds on the 4% lactose diet. There was significant difference (p < 0.01) in weight gain per cage between birds on the 4% and those on the 0% lactose diet (control). All birds on lactose diets were more feed efficient than those on the control diet. Diet did not affect fecal DM but caused high fecal DAPA content (p < 0.05) in 4% lactose birds.

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The Effects Of Small Population Size, Breeding System, And Gene Flow On Fruit And Seed Production In American Ginseng (Panax Quinquefolius L., Araliaceae)., Erin Elizabeth Hackney Jan 1999

The Effects Of Small Population Size, Breeding System, And Gene Flow On Fruit And Seed Production In American Ginseng (Panax Quinquefolius L., Araliaceae)., Erin Elizabeth Hackney

Graduate Theses, Dissertations, and Problem Reports (ETD)

Harvesting of wild American ginseng (Panax quinquefolius L.) has lowered natural population sizes. Accurate assessment of extinction risks necessitates an understanding of the demographic consequences of small populations. I experimentally tested for reproductive limitation of plants in small populations (a form of the Allee effect). I found that fruit production per plant significantly declines in small populations, suggesting mate-limitation of seed set despite the ability of ginseng to self-pollinate. A detailed breeding system study was then carried out, demonstrating that both selfing and outcrossing contribute to seed production. A third study examined the spatial extent of pollen flow in an …

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The Behavioral And Neurochemical Effects Of Prenatal Stress On Stress Responsive Systems In Rats., David Albert White Jan 1999

The Behavioral And Neurochemical Effects Of Prenatal Stress On Stress Responsive Systems In Rats., David Albert White

Graduate Theses, Dissertations, and Problem Reports (ETD)

Research points to a combination of genetic, physiological, and environmental factors in the origin of anxiety and depressive disorders. These factors are adversely impacted by stress and can be influenced by both the prenatal and postnatal environments. Our research shows that offspring of mothers stressed during the last week of gestation appear to be normal in basal behavioral states. However, upon the presentation of stressful stimuli in the forms of anxiogenic drugs (e.g. yohimbine and idazoxan), prenatally stressed offspring respond differentially in comparison with control (normal) offspring. Doses of yohimbine and idazoxan that increased acoustic startle in control animals were …

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The Effect Of Plant Uv-B Absorbing Compounds On Life History Traits And Reproductive Performance In Variable Uv-B Environments., Susan Jill Cooke Jan 1999

The Effect Of Plant Uv-B Absorbing Compounds On Life History Traits And Reproductive Performance In Variable Uv-B Environments., Susan Jill Cooke

Graduate Theses, Dissertations, and Problem Reports (ETD)

Plants often respond to elevated UV-B by increasing the concentration of UV-B absorbing compounds in their tissues. However, evidence that UV-B absorbing compounds confer an adaptive advantage to plants in elevated UV-B environments has not been produced. Three of four experiments utilized an Arabidopsis mutant deficient in the ability to produce flavonoids (a set of UV-B absorbing compounds) to address this question. Results from a life history experiment showed that the wild type out-performed the mutant plants under both UV-B environments, indicating that flavonoids may confer an adaptive advantage across UV-B environments. Germination results were the exception with UV-B initially …

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An Examination Of An Interpersonal Dominance Construct., John Griffin Cole Jan 1999

An Examination Of An Interpersonal Dominance Construct., John Griffin Cole

Graduate Theses, Dissertations, and Problem Reports (ETD)

This study examines the validity and reliability of an interactional measure of Interpersonal Dominance. The study employed surveys from 202 college students, and examined self-report data with regards to two temperament measures (the Eysenck Personality Inventory and the Five-Factor Model of Personality), several trait communication variables (Socio-Communicative Orientation, Communication Apprehension, Self-Report of Immediacy, Shyness, and Verbal Aggression), and the interactional measure of Interpersonal Dominance as advanced by Burgoon, Johnson, and Koch (1998). The study determined that the Interpersonal Dominance measure advanced by Burgoon et al. may in fact be measuring trait communication variables, and not necessarily interaction. This study also …

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The Fernow Experimental Forest: An Analysis Of Historical Change., Jennifer Ann Mccullough Jan 1999

The Fernow Experimental Forest: An Analysis Of Historical Change., Jennifer Ann Mccullough

Graduate Theses, Dissertations, and Problem Reports (ETD)

Three sets of aerial photographs were employed to assess the historical changes within the US Forest Service (USFS) Fernow Experimental Forest in Parsons, West Virginia. The Fernow Experimental Forest was almost entirely clear-cut in the early part of the 20th century prior to its establishment in the 1930s. The USFS photographs acquired in 1956/58, 1972, and 1985 were the main source of data. The photographs were stereoscopically interpreted to identify mature forest, as well as selective cutting, clear-cutting, and areas that were regenerating following logging. The logging classes included areas of selective cutting, clear-cutting, and areas that were regenerating from …

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A Gis Design For Honeybee Management Prototype And Assessment., Jesse Peter Bellavance Jan 1999

A Gis Design For Honeybee Management Prototype And Assessment., Jesse Peter Bellavance

Graduate Theses, Dissertations, and Problem Reports (ETD)

The objective of this thesis project is to design and develop a Geographic Information System (GIS) operation for the primary purpose of managing apiary site information by the state honeybee inspector for West Virginia. Presently, information related to each apiary site is recorded through the use of registration forms, which are mailed and later stored in file cabinets. At this point the flow of information concerning the practice of beekeeping is stymied. Using these filed registration forms as a useful database of information is unwieldy, if not impossible. The purpose of this study is to determine whether a GIS system …

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The Use Of Analog Functional Analysis In Assessing The Function Of Mealtime Behavior Problems., Peter Anthony Girolami Jan 1999

The Use Of Analog Functional Analysis In Assessing The Function Of Mealtime Behavior Problems., Peter Anthony Girolami

Graduate Theses, Dissertations, and Problem Reports (ETD)

Some children exhibit disruptive and self-injurious behavior during mealtime, limiting the positive interaction between care giver and child, and decreasing the probability of a nutritionally adequate intake. Research has demonstrated the utility of functional analysis (i.e., identifying controlling variables of problem behavior) for the development of effective non-aversive interventions for a variety of behavior problems. This study applied the methodology of an analog experimental (functional) analysis of behavior to the specific interaction between care givers and children exhibiting mealtime behavior problems. Five conditions that resemble feeding situations were constructed to identify contingent relations between the mealtime behavior problems exhibited by …

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The Identification Of Criteria And Indicators For The Sustainable Management Of Ecotourism In Taman Negara National Park, Malaysia: A Delphi Consensus., Zaaba Zainol Abidin Jan 1999

The Identification Of Criteria And Indicators For The Sustainable Management Of Ecotourism In Taman Negara National Park, Malaysia: A Delphi Consensus., Zaaba Zainol Abidin

Graduate Theses, Dissertations, and Problem Reports (ETD)

The purpose of this study was to identify sustainability criteria and indicators for evaluating sustainable ecotourism development in Taman Negara National Park (TNNP), Malaysia. This was an attempt to develop sustainability measurements for the evaluation of ecotourism from the theoretical concept of sustainable development. The Delphi method and public survey were used to solicit opinions from an interdisciplinary panel of Malaysian experts and public groups regarding suitable criteria and indicators of sustainability for TNNP. The objectives were to develop a methodology for identifying criteria and indicators, generating criteria and indicators most important for measuring sustainable ecotourism. development and initiating development …

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Perturbation Studies Of Excitable Media, Lisa Elizabeth Seagraves Dec 1998

Perturbation Studies Of Excitable Media, Lisa Elizabeth Seagraves

Graduate Theses, Dissertations, and Problem Reports (ETD)

Poly(N-isopropylacrylamide) (PNIPA) based systems are probably the most often studied polymer gels due to their dramatic change in volume, swelling and deswelling. Since this system has the best response to pH between 4 and 7, the ferrocyanide-iodate-sulfite (FIS) reaction, which exhibits pH oscillations between 4 and 7.5 in a continuously stirred tank reactor (CSTR), is a good candidate for studies of oscillatory gel systems.;This work also focused on two dynamical phenomena in the ruthenium catalyzed Belousov-Zhabotinsky (BZ) reaction. One is self-organized criticality and the other is periodic forcing and how they can be studied with the BZ reaction. Self-organized criticality …

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Modulation Of Aging Process By Diet And Crosslinking Inhibitor And Their Effects On Production In Poultry, Muhammad Iqbal Dec 1998

Modulation Of Aging Process By Diet And Crosslinking Inhibitor And Their Effects On Production In Poultry, Muhammad Iqbal

Graduate Theses, Dissertations, and Problem Reports (ETD)

The factors which influence the age-related decline in production performance and increases in meat toughness in broiler breeder hens are poorly understood. We have hypothesized that the elevated plasma concentration of glucose contributes to the nonenzymatic attachment of glucose to proteins, and generates glycoxidation crosslinks in tissues which can ultimately impair function, is responsible for loss of production. One such crosslink, pentosidine, is an established indicator of both glycative and oxidative tissue damage in mammals. Specifically, the role of diet restriction (DR) and a nucleophilic hydrazine compound, aminoguanidine (AG), a crosslinking inhibitor, were examined on tissue crosslinking with the view …

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Winter Movements And Habitat Use Of Northern Saw-Whet Owls At Assateague Island, Maryland, John Beaudry Churchill Dec 1998

Winter Movements And Habitat Use Of Northern Saw-Whet Owls At Assateague Island, Maryland, John Beaudry Churchill

Graduate Theses, Dissertations, and Problem Reports (ETD)

Ten Northern Saw-whet Owls were radio-tracked over two winters (1996 and 1997) at Assateague Island, Maryland. I used the fixed kernel method to calculate home range estimates for seven owls. Ninety-five percent home range sizes averaged 122.9 ha (range from 39.7--261.9 ha) but varied in size and shape. I also calculated adaptive kernel, harmonic mean, and minimum convex polygon home ranges for comparison of these methods. Habitat composition in 30% home ranges was compared with 95% home ranges and 30% and 95% home ranges were each compared with composition of the entire study area using compositional analysis.;Roost site characteristics were …

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Derepression Of Heterochromatin Inactivation By Induction Of A Nearby Promoter In Drosophila Melanogaster, Daniel Renick Mcneill Dec 1998

Derepression Of Heterochromatin Inactivation By Induction Of A Nearby Promoter In Drosophila Melanogaster, Daniel Renick Mcneill

Graduate Theses, Dissertations, and Problem Reports (ETD)

Position-effect variegation (PEV) describes the compaction of a euchromatic gene placed next to a region of heterochromatin. This compaction into heterochromatin in some instances results in a mosaic phenotype in Drosophila melanogaster. Since its discovery in the 1930's the phenomenon of PEV has been extensively analyzed and many models describing the mechanics have been proposed. But, until recently a model system for analyzing the phenomenon at various developmental stages was not available. In 1996, Lu, Bishop, and Eissenburg were able to use a transgenic construct that variegates for both a heat shock 70 promoter-driven lacZ construct and a mini-white gene, …

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Resistance-In-Series Modeling In High-Shear Rotary Ultrafiltration, Ronald L. Vaughan Jr. Dec 1998

Resistance-In-Series Modeling In High-Shear Rotary Ultrafiltration, Ronald L. Vaughan Jr.

Graduate Theses, Dissertations, and Problem Reports (ETD)

Large volumes of spent oil-in-water emulsions are produced in the metal working (MW) industry. In high-shear rotary ultrafiltration (HSR-UF), disk membranes are rotated at speeds up to 1,750 rpm to generate hydraulic turbulence, which scours the membrane surface. Thus, the pump is required only to provide transmernbrane pressure and a small amount of recirculation.;A parametric waste-specific study was conducted to assess the ability of the resistance-in-series (RIS) permeate flux model to predict pressure-flux data collected in the HSR-UF of a synthetic MW fluid. Experiments were conducted using a pilot-scale HSR-UF system with a 0.11 mum average-pore size membrane at a …

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Characterization Of Diversity Of Fungi Forming Arbuscular Endomycorrhizae In Selected Plant Communities, Sidney Luiz Sturmer Dec 1998

Characterization Of Diversity Of Fungi Forming Arbuscular Endomycorrhizae In Selected Plant Communities, Sidney Luiz Sturmer

Graduate Theses, Dissertations, and Problem Reports (ETD)

Knowledge of taxonomic and functional diversity of arbuscular mycorrhizal fungi (Glomales, Zygomycetes) is important in understanding the biology and ecology of such a widespread mycorrhizal symbiosis. More definitive criteria for grouping and ranking taxa were established by reinterpreting morphological characters in selected species of Glomus (Glomaceae) and Acaulospora and Entrophospora (Acaulosporaceae) based on spore ontogenesis. Members of both families shared some patterns, such as discrete stages of spore growth and differentiation in three phases, resulting in the formation of three possible character complexes: a spore wall, flexible inner walls, and a pregermination structure. Families differed in presence or absence of …

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