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Genetic And Demographic Consequences Of Human-Driven Landscape Changes On Bird Populations: The Case Of Aphrastura Spinicauda (Furnariidae) In The Temperate Rainforest Of South America, Cintia Cornelius

Dissertations

Human activities, such as agriculture and forest exploitation, have modified landscapes worldwide. Despite a large accumulation of empirical and theoretical knowledge on habitat loss and fragmentation, some aspects remain poorly understood, especially those related to interactions between different forms of habitat degradation. The overall goal of this research was to study the effects of forest fragmentation and changes in forest structure on bird populations in a human-modified landscape in the temperate rainforest of South America using Aphrastura spinicauda (Furnariidae) as a model species. I evaluated i) if replacement of forest by open habitat leads to reduced dispersal influencing the genetic …

Seed Dispersal Limitation In A Neotropical Nutmeg, Virola Flexuosa (Myristicaceae): An Ecological And Genetic Approach, Kimberly Mae Holbrook

Dissertations

Seed dispersal contributes significantly to tropical forest maintenance, influencing processes, such as metapopulation dynamics and population persistence. Although several hypotheses have been debated regarding the contribution of seed dispersal to tropical forest diversity, recent work suggests that dispersal limitation is a major component in determining plant population patterns. This dissertation research broadly addresses hypotheses that seed dispersal behaviour of frugivores influences dispersal limitation of a Neotropical tree, Virola flexuosa (Myristicaceae). To test these hypotheses, I studied how different frugivores influenced seed dispersal of V. flexuosa at two sites in Amazonia Ecuador. General research objectives were to estimate fruit removal by …

Behavioral Tolerance Under Variable Ratio Schedules Of Reinforcement, Barry Eshkol Adelman

Dissertations

Previous studies (e.g., Hoffman, Branch, & Sizemore, 1987) have demonstrated that greater drug tolerance develops in responding under fixed-ratio (FR) schedules of reinforcement when the schedule parameter is small than when it is large; little research has been done on related schedules such as variable-ratio (VR). In Experiment 1, three pigeons responded under a multiple FR 5 FR 125 VR 5 VR 125. A range of prechronic doses of cocaine produced dose-dependent reductions in response rates under the component schedules. Following chronic dosing with daily administrations of 5.6 mg/kg, similar dose-response curves were derived by substitutions of the usual dose. …

The Global Hepatic Transcriptional Response Of Male Fisher Rats To Dietary Aroclor 1254 Exposure, Trisha M. Basford

Dissertations

Dietary intake is a primary route for biomagnification of environmentally persistent polychlorinated biphenyls (PCBs) within humans and animals. Aroclor 1254, a mixture of PCBs, is associated with a variety of toxic responses including alterations in blood and lipid biochemistry and tumor promotion. Measurement of the transcriptional responses to low-level dietary exposure to A1254 has not been reported to date, and is important given the persistence of PCBs, and range of effects associated with exposure. The aims of this study were to characterize changes in rat hepatic global gene expression due to sub-acute and sub-chronic dietary exposure to A1254, and to …

Thereby Become A Monster: Complex Organizations And The Torture At Abu Ghraib, Janine A. Bower

Dissertations

Reasearch and theory on organizational crime and deviance suggest organizational offending includes aspects of the environment, organizational characteristics (such as tasks, structure, and processes), and cognition, and is systematically produced by the combination of these three. This research is an examination of the organization of the Abu Ghraib detention and interrogation facility in Iraq, the location of prison abuses now made infamous following their public disclosure in 2004. An ethnographic content analysis of documents was performed to probe organizational culture, structure and processes, and their intersection with individual biographies and contextual forces. While public questions focused on why seemingly ordinary …

Characterization Of Molecular Events Following Heavy Metal Cadmium Exposure: A Cellular Regulatory Symphony In Response To Early Cadmium Insult, Chin-Ju Jean Hsiao

Dissertations

Cadmium, a non-essential toxic heavy metal, has been classified as a human carcinogen and one of the most hazardous substances in our environment. Since it can circulate within the food chain, has a long biological half-life and can bio-accumulate, it has the potential to induce detrimental health effects linked to toxicity, cancer and chronic diseases.

In recent years progress has been made to dissect and understand the molecular mechanisms underlying the effects of cadmium exposure. However, few studies have focused on investigating potential protective and/or defense mechanisms naturally applied by cells upon initial exposure, prior to any damage or toxic …

Structure-Function Studies Of Self- Assembling Flagellin Proteins Fromsalmonella Typhimurium And Aquifex Pyrophilus, Venkata Raghu Ram Malapaka

Dissertations

The eubacterial flagellum is a complex structure with an elongated extracellular filament that is primarily composed of a single protein termed flagellin. The highly conserved N-and C- termini of flagellin are important in its export and assembly, whereas the middle "hypervariable" region is highly variable in size across different species and is largely dispensable. InSalmonella typhimurium phase 1 flagellin (FliC), this hypervariable region encodes two solvent-exposed D2 and D3 domains. The functional role of this knob-like structural feature in motility remains unclear. The structural and physiological role of the hypervariable region in flagellar assembly, stability and cellular motility was investigated. …

A Role Of Problem-Solving In Complex Intraverbal Repertoires, Rachael A. Sautter

Dissertations

kinner described intraverbal behavior as verbal behavior with no point-to-point correspondence between the stimulus and the response. This verbal operant encompasses a wide range of response topographies ranging from answering simple questions to complex conversational exchanges. Previous interventions for teaching complex responding to questions about category membership have focused primarily on transfer of stimulus control procedures to teach specific intraverbal responses. These procedures have proven effective at establishing basic intraverbal responses but have consistently produced small and somewhat restricted repertoires. Theoreticians have hypothesized that effective use of problem-solving strategies rather than simple stimulus control may account for the performance of …

Four Roads: A Novel, Kelly Daniels

Dissertations

An American tourist is attacked by peasants, who suspect her of stealing infants to sell on a shadowy organ donation market. Several other attacks follow, prompting a travel advisory, which in turn causes tourists to flee the country, fracturing the already weak economy, and creating more chaos still. Meanwhile, death squads patrol the mountains to "disappear" anyone suspected of harboring sympathy for the rebels, and the usual assortment of criminals use any means available to make a buck. This is Guatemala, hardly a vacationer's paradise; yet several Americans have elected to remain in country amidst such turmoil.

Four Roads, a …

In Vitro Studies Of Degradation And Bioactivity Of Aliphatic Polyesther Composites, Georgia Chouzouri

Dissertations

In spite of numerous publications on the potential use of combinations of aliphatic polyester composites containing bioactive fillers for bone regeneration, little information exists on the combined in vitro mechanisms involving simultaneously diffusion for polymer degradation and bioactivity through nucleation and growth of apatite in simulated body fluid (SBF) solution. The objective of this study is to contribute to the understanding of the fundamentals in designing non-porous, solid materials for bone regeneration, from experimental data along with their engineering interpretation.

Bioactivity, in terms of apatite growth, was assessed through several experimental methods such as scanning electron microscopy (SEM), energy dispersive …

Comparative Immune Function In Wild Birds, Kevin David Matson

Dissertations

Over the last several decades, interest in quantifying immune function in comparative studies of wild animals has grown appreciably. Now, the field of ecological immunology is undergoing a transition, and ¿second generation¿ studies are being designed and carried out. With a greater appreciation of the complexity of immune systems, these second generation studies are commonly distinguished from their antecedents by making comparisons using multiple assays and including multiple species. I worked to advance this transition by developing novel approaches to comparative immunology, exploring the interrelationships among indices of immune function, and applying multiple indices to a question of comparative avian …

The Role Of Local And Regional Factors In The Foraging Ecology Of Birds Associated With Polylepis Woodlands, Grace Patricia Servat-Valenzuela

Dissertations

Understanding the extent to which patterns of functional structure are repeated in space and the scale at which different factors (local and regional) operate to explain community patterns are of important in community ecology. I studied the extent of spatial variation in foraging ecology of birds in the Polylepis community, a vegetation system of the Andes, in regard to variation in local (vegetation structure, floristic composition, food resources) and regional factors (biogeography). Specifically, I studied foraging ecology of nine insectivorous bird species (and the assemblage they conform) across twelve disjunct woodlands embedded in three biogeographic regions of the Peruvian Andes. …

E-Portfolios: Their Impact On Preservice Teachers' Self-Directed Learning And Computer Technology Skills, Yufang Carole Huang

Dissertations

Students in the Teacher Education Program at the University of Missouri-St. Louis have to complete their professional E-portfolios to be certified for the program. An E-portfolio demonstrates a future teacher¿s knowledge, skills, and abilities acquired through teaching and learning. Five qualitative case studies were investigated to understand how E-portfolios impact preservice teachers¿ self-directed learning readiness (SDLR) and computer technology skills (CTS). Data were gathered from the preservice teachers¿ pre- and post-questionnaires, interviews, observations, and their completed E-portfolios. Two internship students and three student teachers were observed creating their E-portfolios during a 16-week semester. During the period, some sought assistance from …

Communication And Leadership: Faculty Perceptions Of The Department Chair, Kathleen Czech Edd

Dissertations

With department chairs providing a critical link between faculty and administration, their leadership impacts universities on a broad level. However, chairs often report dissatisfaction with the position and experience rapid turnover. In an effort to help understand the role that communication plays in effective leadership for department chairs, this study provides an empirical test of Gibb's theory of defensive vs. supportive communication. As such, this project investigated the communication and leadership behaviors of university department chairs as evaluated by their faculty members. Specifically, 202 randomly selected faculty members from colleges and universities affiliated with the Council of Independent Colleges, Washington, …

Transition To Nursing Home Of Korean-American Elders, Myungja Kim Hahm Phd

Dissertations

The purpose of this study was to explore factors affecting Korean-American (KA) elders during the transition to nursing homes in the first month following admission. The three aims of this proposed study were (1) to explore culture specific factors that affect KA elders' perspectives during the transitional period to a nursing home, (2) to identify thoughts and feelings of KA elders about their admission into a nursing home, (3) to describe the adjustment process associated with admission to a nursing home. A grounded theory design was utilized to explore KA elders' perceptions/experiences associated with adjustment to a nursing home. Open-ended, …

Experiences Of Sacramental Marriage, James Patrick O'Brien Edd

Dissertations

This study interprets the stories told by eight couples about their experiences approaching marriage as a religious sacrament. The eight couples represented a purposeful sample selected using the following criteria: (a) They self-identified as having a sacramental marriage within the Roman Catholic tradition; (b) they appeared to be information rich sources who could provide an emic, i.e., an insider, view of the sacramental marriage experience; (c) they participated in the Catholic Cursillo movement; (d) they engaged in observable religious practices; and (e) they parented children. Research methods included guided conversation, participant observation, and a timeline activity that asked participants to …

Emerging Elements Of Leadership In A Complex System: A Cognitivist Approach, Kirsten Suzanne Hanson Edd

Dissertations

As our world grows increasingly complicated at an intensified pace, leaders must be facile managers of complexity if organizations and society are to productively and peacefully evolve. Today’s global corporations are microcosms of complexity and have the potential to affect life for almost all other species. However, many organizations have not yet become aware of themselves as “living” and still operate as industrial age institutions with rationalist thinking traditionally dominating management practice. Many factors impact an organization’s overall effectiveness. Yet, executive leaders are seen as having the ability to influence change and play a vital role in helping people navigate …

Global And Quantitative Gene Expression Analysis Of The Effects Of Drinking Water Exposure To Lead Acetate In Fisher 344 Male Rats Liver, Worlanyo Eric Gato

Dissertations

The primary objective of this research is to analyze global gene expression patterns occurring in Fisher 344 rat livers exposed to varying levels of lead and times. The hypotheses were that: (1) effects associated with Pb exposure are both dose and time dependent and (2) several genes will be over-expressed or repressed including transcripts associated with calcium signaling. Initially, the effects of Pb exposures upon morphometnc indices, liver and kidney tissue histology, Pb distribution, Pb interaction with other trace metals including Zn, Cu, Co, Fe, Ni and Ca were assessed. Results showed a significant accumulation of lead in blood, liver, …

Fluency In Pigeons: The Effects Of Response Rate On Learning, Matthew L. Porritt

Dissertations

Instructional procedures that build high response rates are purported to have significant benefits over procedures that do not focus on fast responding (Binder, 1996). However, much of the research exploring rate-building procedures is confounded by two variables: rate of reinforcement and number of exposures (Doughty, Chase, & O'Shields, 2004). In six experiments, the present study examined the effects of three variables, rate of reinforcement, number of exposures, and rate of responding, on learning under rate-building procedures in pigeons. In Experiment 1, rate-building produced significantly better learning outcomes when compared to a rate-controlled condition with number of exposures held constant. In …

Modeling Projection Neuron And Neuromodulatory Effects On A Rhythmic Neuronal Network, Nicholas Kintos

Dissertations

Projection neurons shape the activity of many neural networks. In particular, neuromodulatory substances, which are often released by projection neurons, alter the cellular and/or synaptic properties within a target network. However, neural networks in turn influence projection neuron input via synaptic feedback. This dissertation uses mathematical and biophysically-realistic modeling to investigate these issues in the gastric mill (chewing) motor network of the crab, Cancer borealis. The projection neuron MCN1 elicits a gastric mill rhythm in which the LG neuron and INTl burst in anti-phase due to their reciprocal inhibition. However, bath application of the neuromodulator PK elicits a similar gastric …

Enhancement Of Fluidization And Filtration Using Nanoparticle Agglomerates And Aerogels, Jose A. Quevedo

Dissertations

Previous works have classified the fluidization behavior of nanoparticles as Agglomerate Particulate Fluidization (APF) and Agglomerate Bubbling Fluidization (ABE). These fluidization behaviors are quite different in regard to the fluidized bed expansion, the presence of bubbles and the smoothness of the bed surface, with APF nanopowders showing a much more homogeneous fluidization and a much better dispersion than ABE nanopowders which are generally very difficult to fluidize and show vigorous bubbling. In the present work, the fluidization of APF as well as ABF nanopowders is studied in depth, both conventionally, and in the presence of extemal assistance; several related topics …

Demonstrating Experiential Learning At The Graduate Level Using Portfolio Development And Reflection, David Winslow Rausch

Dissertations

Problem. Various guidelines for assessment have been developed in an effort to promote academic quality and integrity for educational programs that recognize experiential learning. The purpose of this present study was to determine the extent to which experiential learning and assessment, through portfolio development, help adult students in a graduate-degree program demonstrate graduate-level learning and competency.

Method. This qualitative single-case study used the assessment processes and outcomes elements of the Jackson and Maclsaac process model to analyze the use of reflective practice and the use of portfolios in a graduate education program. Data were triangulated using individual interviews and the …

The Relationship Between Nurse Manager Leadership Attributes And Nurse Clinical Autonomy: Magnet Versus Non-Magnet Hospitals, Catherine A. Verkaaik Phd

Dissertations

Purpose: This research evaluated relationships among hospital types (Magnet versus non-Magnet), nurse manger leadership attributes, and staff registered nurse autonomy. Hypothesis: Magnet hospital status would be related to positive nurse manager leadership attributes which would be related to greater clinical nurse autonomy and nurse manager leadership would mediate relationships between hospital status and clinical nurse autonomy. Conceptual Basis and Background: Structural Contingency Theory modified in the Nursing Systems Outcomes Research model was the research model for conceptualizing the structure-environment-effectiveness relationship. Critical Social Theory (CST) provided the conceptual/motivational basis for this study, a lens through which to frame the question. Clinical …

The Effectiveness Of Rating Scales And Semi-Structured Interview In Diagnosing Adult Attention Deficit Hyperactivity Disorder, Carolyn Mae Cofrancesco

Dissertations

Problem and purpose. There are few standardized tools for diagnosing ADHD in adults. The purpose of this study was to compare a standardized rating scale (CAARS) used by different observers, with a comprehensive diagnostic interview (CAADID) with respect to their ability to diagnose subtypes of ADHD.

Method. Subjects for this study came from baseline data of 98 patients (18 to 60 years ofage) participating in a drug trial for adult ADHD. The CAADID interview results in a yes-no decision as to whether the patient meets DSM-IV criteria for the subtypes ADHD. A t -test was used to compare the CAADID-diagnosed …

The Iron Age I Structure On Mount Ebal: Excavation And Interpretation, Ralph K. Hawkins

Dissertations

Problem. The Iron Age I site on Mt. Ebal, discovered in 1980 by Adam Zertal and excavated between 1982 and 1989, has remained largely unknown by both the scholarly community and the public. No scholarly congress or colloquium has ever been held regarding the Mt. Ebal excavations. The Mt. Ebal excavations, however, may have important implications for reconstructing Israelite origins. This present study investigates the Mt. Ebal excavationand its results.

Method. My study uses the comparative method and is divided into six chapters. Chapter 1 serves as in introduction, giving an overview of the investigation to be carried out in …

An Evaluation Of Reserve Component Leaders' Attitudes And Motivation As They Relate To Situational Leadership Theory In A Peacekeeping Operational Environment, Clark C. Barrett

Dissertations

Program. This study investigated the relationships between Reservist leaders' attitudes and Hersey and Blanchard's Situational Leadership Theory (SLT), and Thomas's Integrative Model of Intrinsic Motivation during a 2004 Sinai, Egypt, peacekeeping mission.

Methodology. This descriptive study provided quantitative and qualitative results. Three instruments were used with a convenience sample of leaders within one forward-deployed National Guard infantry battalion. The LEADSelf instrument determined the SLT style of unit officers and non-commissioned officers. The Thomas Empowerment Survey profiled participants' intrinsic motivation. A researcher-developed survey determined preferences for intrinsic versus extrinsic motivator factors.

The study centered on the following issues: (1) Are the …

Religion And Semiosphere: From Religious To The Secular And Beyond, Rajka Rush

Dissertations

Religion is a system of structural ideas that involve the natural ability of the mind to engage itself into the process of unlimited semiosis which can be defined as an existential openness of one's consciousness to the universe as a system. This primary religious consciousness becomes limited by language, symbolic, and cultural constraints. The religious semiotic space is a sub-cultural system open to culturally and cross-culturally encoded idioms and concepts. These cultural potentials are interpreted and settled by the religious exegesis expressed in the behavioral patterns of the symbolic actions that reflect a specific worldview of the closed community controlled …

Trends In Historic And Modern Performance Practice For The Trumpet In Richard Wagner’S Der Ring Des Nibelungen, Michael Ryan Ellzey

Dissertations

The purpose of this document is to compare the Alto F trumpet used by the players of Richard Wagner’s orchestra to the modem trumpet, with reference to specific excerpts from Der Ring des Nibelungen. It will discuss topics pertaining to transposition, range, keys, timbre, and crooking. Other elements that will be explored are the evolution of the valved trumpet and how it led to the Alto F trumpet. The document will also discuss the eventual replacement of the Alto F trumpet by the modem C and B-flat trumpets. Included in this section will be a historic study of the …

Beholding The Beauty Of Self: The Psychological Integration Of The Afrocentric-Self Among African-American Females Socialized In A Eurocentric Aesthetic, Donna Lynn Cook Phd

Dissertations

Self-esteem and body image disturbances prominently figure into many physical and psychological health disorders such as depression, eating disorders, anxiety disorders, and chemical dependency. In Euro-American culture, media images of femininity and physical attractiveness reinforce generally held perceptions of the idealized female beauty as tall, white, slender, and often blond and blue eyed. The physical morphology of African-American women does not genetically "fit" this westernized standard of beauty with implications for their mental health. The socialization of African-American women in a culture that embraces a different ethnic standard of beauty influences their perceptions of how physically attractive they see themselves. …