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2013

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Development Of Laser Spectroscopy For Elemental And Molecular Analysis, Yuan Liu Jan 2013

Development Of Laser Spectroscopy For Elemental And Molecular Analysis, Yuan Liu

Electronic Theses and Dissertations

Laser-Induced Breakdown Spectroscopy (LIBS) and Raman spectroscopy are still growing analytical and sensing spectroscopic techniques. They significantly reduce the time and labor cost in analysis with simplified instrumentation, and lead to minimal or no sample damage. In this dissertation, fundamental studies to improve LIBS analytical performance were performed and its fusion with Raman into one single sensor was explored. On the fundamental side, Thomson scattering was reported for the first time to simultaneously measure the electron density and temperature of laser plasmas from a solid aluminum target at atmospheric pressure. Comparison between electron and excitation temperatures brought insights into the …

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Investigation Of A Novel Magnesium And Acidified Ethanol System For The Degradation Of Persistent Organic Pollutants, Phillip Maloney Jan 2013

Investigation Of A Novel Magnesium And Acidified Ethanol System For The Degradation Of Persistent Organic Pollutants, Phillip Maloney

Electronic Theses and Dissertations

For centuries chemists have sought to improve humankind’s quality of life and address many of society’s most pressing needs through the development of chemical processes and synthesis of new compounds, often with phenomenal results. Unfortunately, there also are many examples where these chemicals have had unintended, detrimental consequences that are not apparent until years or decades after their initial use. There are numerous halogenated molecules in this category that are globally dispersed, resistant to natural degradation processes, bioaccumulative, and toxic to living organisms. Chemicals such as these are classified as persistent organic pollutants (POPs), and due to their negative environmental …

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Spectrally Uniform Frames And Spectrally Optimal Dual Frames, Saliha Pehlivan Jan 2013

Spectrally Uniform Frames And Spectrally Optimal Dual Frames, Saliha Pehlivan

Electronic Theses and Dissertations

Frames have been useful in signal transmission due to the built in redundancy. In recent years, the erasure problem in data transmission has been the focus of considerable research in the case the error estimate is measured by operator (or matrix) norm. Sample results include the characterization of one-erasure optimal Parseval frames, the connection between two-erasure optimal Parseval frames and equiangular frames, and some characterization of optimal dual frames. If iterations are allowed in the reconstruction process of the signal vector, then spectral radius measurement for the error operators is more appropriate then the operator norm measurement. We obtain a …

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Prediction Of Optical Properties Of Pi-Conjugated Organic Materials For Technological Innovations, Iffat Nayyar Jan 2013

Prediction Of Optical Properties Of Pi-Conjugated Organic Materials For Technological Innovations, Iffat Nayyar

Electronic Theses and Dissertations

Organic π-conjugated solids are promising candidates for new optoelectronic materials. The large body of evidence points at their advantageous properties such as high charge-carrier mobility, large nonlinear polarizability, mechanical flexibility, simple and low cost fabrication and superior luminescence. They can be used as nonlinear optical (NLO) materials with large two-photon absorption (2PA) and as electronic components capable of generating nonlinear neutral (excitonic) and charged (polaronic) excitations. In this work, we investigate the appropriate theoretical methods used for the (a) prediction of 2PA properties for rational design of organic materials with improved NLO properties, and (b) understanding of the essential electronic …

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Cerium Oxide Nanoparticles Sensitize Pancreatic Cancer Cells To Radiation By Promoting Acidic Ph, Ros, And Jnk Dependent Apoptosis, Melissa Wason Jan 2013

Cerium Oxide Nanoparticles Sensitize Pancreatic Cancer Cells To Radiation By Promoting Acidic Ph, Ros, And Jnk Dependent Apoptosis, Melissa Wason

Electronic Theses and Dissertations

Side effects of radiation therapy (RT) remain the most challenging issue for pancreatic cancer treatment. In this report we determined whether and how cerium oxide nanoparticles (CONPs) sensitize pancreatic cancer cells to RT. CONP pretreatment enhanced radiation-induced reactive oxygen species (ROS) production preferentially in acidic cell-free solutions as well as acidic human pancreatic cancer cells. In acidic environments, CONPs favor the scavenging of superoxide radical over the hydroxyl peroxide resulting in accumulation of the latter whereas in neutral pH CONPs scavenge both. CONP treatment prior to RT markedly potentiated the cancer cell apoptosis both in culture and in tumors and …

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Hidden In Plain Sight: Development And Testing Of A Model To Evaluate Political Leadership Tactics, Albert Citron Jan 2013

Hidden In Plain Sight: Development And Testing Of A Model To Evaluate Political Leadership Tactics, Albert Citron

Electronic Theses and Dissertations

This thesis analyzes the kinds of verbal and nonverbal signals elites manifest to show leadership qualities. Launching from Max Weber’s conceptual framework of charisma as a power term and Harold Lasswell’s study of propaganda, this study takes a multidisciplinary approach to studying political leadership with elements of communication methodology and an ontological basis in evolutionary psychology. The study’s goal is to offer a framework for defining and evaluating the diverse signal patterns employed by political elites in three real-life situations. These are the Malta Summit, the 1992 Virginia Presidential Debate, and the 2012 South Carolina Republican Presidential Primary. The cases …

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Stereotypes, Perceptions Of Similarity, And Cultural Identity: Factors That May Influence The Academic Achievement Of Immigrant Students., Tamara Fagan Jan 2013

Stereotypes, Perceptions Of Similarity, And Cultural Identity: Factors That May Influence The Academic Achievement Of Immigrant Students., Tamara Fagan

Electronic Theses and Dissertations

For decades, the United States has been known as the nation of immigrants due to the increasing number of immigrant students in the public school system. Although the population of immigrant students steadily increases annually, American society still pressures immigrants into acculturation to fulfill the United States ideals of academic achievement despite the United States claim of multiculturalism (Malcolm & Lowery, 2011). This research focuses on 1st - and 2nd generation immigrant students’ strife of acceptance in U.S. culture, while sill preserving their own native culture, and the influence it has on academic achievement. The researcher interviewed eight (8) adult …

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Currency In Transition: An Ethnographic Inquiry Of Bitcoin Adherents, Justin Fletcher Jan 2013

Currency In Transition: An Ethnographic Inquiry Of Bitcoin Adherents, Justin Fletcher

Electronic Theses and Dissertations

The Internet and other telecommunications systems have reshaped the means by which markets are accessed, generated, and transformed. Recent innovations in computer science have led to the development of a virtually bound, decentralized, encrypted currency system known as bitcoin. Unlike conventional currency systems, the Bitcoin protocol is cryptologically defined with a virtual structure that allows it to simultaneously operate as currency, commodity, and market shaping socio-political force. Its decentralized design permits it to function as a free-market response to fiat currencies vulnerable to inflation, regulation, and manipulation. Given the cultural significance anthropologists and other social scientists have assigned to various …

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Interpreting Diet And Nutritional Stress In Napoleon's Grand Army Using Stable Carbon And Nitrogen Isotope Analysis, Sammantha Holder Jan 2013

Interpreting Diet And Nutritional Stress In Napoleon's Grand Army Using Stable Carbon And Nitrogen Isotope Analysis, Sammantha Holder

Electronic Theses and Dissertations

A mass grave containing the remains of at least 3269 Napoleonic soldiers from 1812 was discovered in Vilnius, Lithuania in 2001. Stable carbon and nitrogen isotopic analyses were performed on collagen from 78 femoral samples to explore dietary variation within the sample. Starvation and nutritional distress were also evaluated through the examination of nitrogen enrichment in bone collagen. Clinical studies have demonstrated that enriched nitrogen isotope values can indicate periods of nutritional stress and starvation; however, this is the first study to examine its use as a diagnostic indicator of starvation in a historical population using bone tissue. According to …

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Inverse Intuition: Repurposing As A Method To Create New Artifacts, To Invent New Practices, And To Produce New Knowledge, Warren Jones Jan 2013

Inverse Intuition: Repurposing As A Method To Create New Artifacts, To Invent New Practices, And To Produce New Knowledge, Warren Jones

Electronic Theses and Dissertations

This dissertation argues that Digital Natives, rather than employing novel ways of thinking (such as those suggested by Walter Ong's concept of Second Orality), are in fact employing a way of thinking that has always existed: repurposing. Ruth Oldenziel discusses how, historically, women used "a kind of mental quality" enabling them to re-use objects in novel ways to accomplish more of life's tasks. My research led me to investigate how a wide variety of people, especially historically marginalized people, used this kind of mental quality. This dissertation explores repurposing's real world uses as well as its uses in narratives, specifically …

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Wetland Diversity In A Disturbance-Maintained Landscape: Effects Of Fire And A Fire Surrogate On Aquatic Amphibian Survival And Species Depauperateness., Joyce Klaus Jan 2013

Wetland Diversity In A Disturbance-Maintained Landscape: Effects Of Fire And A Fire Surrogate On Aquatic Amphibian Survival And Species Depauperateness., Joyce Klaus

Electronic Theses and Dissertations

Disturbance is one of the central concepts explaining how diversity arises and is perpetuated in ecological time. A good model system for testing hypotheses related to disturbance is the longleaf pine ecosystem in the southeastern U.S. because in this ecosystem frequent, low-severity fires acts as a disturbance that maintains a unique vegetation structure and high species richness. Vegetation structure influences animal distributions; in fire-dependent ecosystems many animals rely on open-structured, fire-maintained vegetation but shrubs and trees encroach into fire-dependent ecosystems where fire has been excluded. Prescribed burning and mechanical removal are commonly used as restoration tools to control encroachment. To …

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Naep-Related Visual Arts Assessment In Classroom Applications, Debra Mcgann Jan 2013

Naep-Related Visual Arts Assessment In Classroom Applications, Debra Mcgann

Electronic Theses and Dissertations

This action research study investigates classroom visual art assessments and their potential to improve teacher instruction and student learning. In order to examine this topic more thoroughly, a National Assessment of Educational Progress (NAEP)-related classroom assessment was designed and administered to the researcher’s Drawing and AP Art History classes. Students were also asked to fill out a questionnaire that asked about their past art experiences and motivation to participate in art activities such as creating artwork outside of the school setting or attending an art museum. Students observed, described, and analyzed contemporary artwork, and they created and wrote about their …

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A Study Of Student Achievement And Educational Intervention Strategies In Traditional And Virtual Format Algebra 1 Courses Within Volusia County School District, Paul Nehrig Jan 2013

A Study Of Student Achievement And Educational Intervention Strategies In Traditional And Virtual Format Algebra 1 Courses Within Volusia County School District, Paul Nehrig

Electronic Theses and Dissertations

The purpose of this study was to compare achievement results of students enrolled in traditional and virtual Algebra 1 courses in the School District of Volusia County, Florida and to identify which educational interventions are utilized by traditional and online teachers to promote student success, especially for at-risk populations. Two research questions guided this study. This study is significant, as school districts expand virtual options for K-12 students to meet legislative mandates and student demand, while also exploring and developing methods to ensure student success. Student scores on the Florida Algebra 1 End of Course Exam (EOC) were compared to …

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Utilizing Ipads To Enhance Student Engagement In Vocabulary Learning: A Case Study, Sarah Park Jan 2013

Utilizing Ipads To Enhance Student Engagement In Vocabulary Learning: A Case Study, Sarah Park

Electronic Theses and Dissertations

According to research evidence, the relationship between vocabulary and reading proficiency is so powerful that it is a valuable predictor of reading comprehension and academic achievement in the later school years (Scarborough, 2011). The major contributor to reading problem is the vocabulary demand of texts that students are assigned in school (Mckeown, Corsson, Arts, Sandora, & Beck, 2012). National Assessment of Education Progress (National Center for Education Statistics, 2012) stated the essential link between the words students know and students’ ability to use those words to understand what they read. Therefore, researchers and educators have both agreed the importance of …

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Gender Differences And Fast Food Preferences Among U.S. College Students, Donald Persaud Jan 2013

Gender Differences And Fast Food Preferences Among U.S. College Students, Donald Persaud

Electronic Theses and Dissertations

The intent of this research is to examine the relationship of corporate fast food and health within the context of gender. It tests the hypothesis that Western perceptions of masculinity and femininity inform a differentiated pattern of food preference, which will correlate with health as measured by Body Mass Index (BMI). The targeted sample population for the study is the undergraduate community of the University of Central Florida, and fast food is a chosen dietary medium because it is an increasingly ubiquitous source of caloric energy in the American foodscape, representative of the mass production model applied to cuisine in …

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Road Networks, Social Disorganization And Lethality, An Exploration Of Theory And An Examination Of Covariates, Aaron Poole Jan 2013

Road Networks, Social Disorganization And Lethality, An Exploration Of Theory And An Examination Of Covariates, Aaron Poole

Electronic Theses and Dissertations

Utilizing a Criminal Event Perspective, the analyses of this dissertation test a variety of relationships to the dependent variable: the Criminal Lethality Index. Data from the National Incident-Based Reporting System, the Census and American Community Survey, the American Trauma Society, and data derived from the Census’s mapping TIGER files are combined to create a database of 190 cities. This database is used to test road network connectivity (Gama Index), medical resources, criminal covariates and Social Disorganization variables in relation to a city’s Criminal Lethality Index. OLS regression demonstrates a significant and negative relationship between a city’s Gama Index and its …

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Do Changes In Muscle Architecture Effect Post- Activation Potentiation, Danielle Reardon Jan 2013

Do Changes In Muscle Architecture Effect Post- Activation Potentiation, Danielle Reardon

Electronic Theses and Dissertations

Purpose: To examine the effect of three muscle potentiation protocols on changes in muscle architecture and the subsequent effect on jump power performance. Methods: Maximal (1RM) squat strength (Mean SD=178.3 ± 36.6kg), vertical jump power, and muscle architecture were obtained in 12 resistance trained men (25.2±3.6y; 90.67±12.7kg). Participants randomly completed three squatting protocols at 75% (3 x 10 reps), 90% (3 x 3 reps) or 100% (1 x 1) of their 1RM, or no workout (CON), with each protocol being separated by one week. During each testing session ultrasound and vertical jump testing were assessed at baseline (BL), 8min post …

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The Red Scare And The Bi's Quest For Power: The Soviet Ark As Political Theater, Austin Smith Jan 2013

The Red Scare And The Bi's Quest For Power: The Soviet Ark As Political Theater, Austin Smith

Electronic Theses and Dissertations

The Red Scare of 1919-1920 has been presented as a wave of anti-Radical hysteria that swept post WWI America; a hysteria to which the state reluctantly capitulated to by arresting Radicals and deporting those alien Radicals they deemed most threatening. This presentation, however, is ludicrous when the motivations of the state and its conservative allies are examined. The truth of the matter was that almost all of the people targeted by the Red Scare represented no significant threat to the institutions of the United States and were merely targeted for holding Leftwing ideas, or being connected to a group that …

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Re-Imaging A Career In Filmmaking, Jason Sutton Jan 2013

Re-Imaging A Career In Filmmaking, Jason Sutton

Electronic Theses and Dissertations

The purpose of this project was to learn every aspect of the film business, and to do so within the guidelines of an ultra-low budget digital format. This meant creating a project that could be written, produced, and directed all for fewer than fifty thousand dollars. All of the money had to be raised by me as well. The process began day one in the classroom, learning every step of the way. It began by turning an idea into a feature length film script. This was done over the course of a year. The next step began putting together every …

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From Skeptical Disinterest To Ideological Crusade: The Road To American Participation In The Greek Civil War, 1943-1949, Stephen Villiotis Jan 2013

From Skeptical Disinterest To Ideological Crusade: The Road To American Participation In The Greek Civil War, 1943-1949, Stephen Villiotis

Electronic Theses and Dissertations

This thesis examines the way in which the United States formulated its policy toward Greece during the Greek civil war (1943-1949). It asserts that U.S. intervention in Greece was based on circumstantial evidence and the assumption of Soviet global intentions, rather than on dispatches from the field which consistently reported from 1943-1946 that the Soviets were not involved in that country’s affairs. It also maintains that the post-Truman Doctrine American policy in Greece was in essence, a continuation of British policy there from 1943-1946, which meant to impose an unpopular government on the people of Greece, and tolerated unlawful violence …

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The Effects Of Diagnostic Aiding On Situation Awareness Under Robot Unreliability, David Schuster Jan 2013

The Effects Of Diagnostic Aiding On Situation Awareness Under Robot Unreliability, David Schuster

Electronic Theses and Dissertations

In highly autonomous robotic systems, human operators are able to attend to their own, separate tasks, but robots still need occasional human intervention. In this scenario, it may be difficult for human operators to determine the status of the system and environment when called upon to aid the robot. The resulting lack of situation awareness (SA) is a problem common to other automated systems, and it can lead to poor performance and compromised safety. Existing research on this problem suggested that reliable automation of information processing, called diagnostic aiding, leads to better operator SA. The effects of unreliable diagnostic aiding, …

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Theoretical And Computational Studies Of Diffusion Of Adatom Islands And Reactions Of Molecules On Surfaces, Syed Islamuddin Shah Jan 2013

Theoretical And Computational Studies Of Diffusion Of Adatom Islands And Reactions Of Molecules On Surfaces, Syed Islamuddin Shah

Electronic Theses and Dissertations

The work presented in this dissertation focuses on the study of post deposition spatial and temporal evolution of adatom islands and molecules on surfaces using ab initio and semiemperical methods. It is a microscopic study of the phenomena of diffusion and reaction on nanostructured surfaces for which we have developed appropriate computational tools, as well as implemented others that are available. To map out the potential energy surface on which the adatom islands and molecules move, we have carried out ab initio electronic structure calculations based on density functional theory (DFT) for selected systems. For others, we have relied on …

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Optically Isotropic Liquid Crystals For Display And Photonic Applications, Jin Yan Jan 2013

Optically Isotropic Liquid Crystals For Display And Photonic Applications, Jin Yan

Electronic Theses and Dissertations

For the past few decades, tremendous progress has been made on liquid crystal display (LCD) technologies in terms of stability, resolution, contrast ratio, and viewing angle. The remaining challenge is response time. The state-of-the-art response time of a nematic liquid crystal is a few milliseconds. Faster response time is desirable in order to reduce motion blur and to realize color sequential display using RGB LEDs, which triples the optical efficiency and resolution density. Polymer-stabilized blue phase liquid crystal (PS-BPLC) is a strong candidate for achieving fast response time because its self-assembled cubic structure greatly reduces the coherence length. The response …

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Computational Approach To The Problems Of Electro- And Photo-Catalysis, Sebastian Zuluaga Jan 2013

Computational Approach To The Problems Of Electro- And Photo-Catalysis, Sebastian Zuluaga

Electronic Theses and Dissertations

The main objective of this work is to gain basis for rational design of catalysts used in fuel cells for conversion of chemical energy stored in hydrogen molecules into electric energy, as well as photo-catalysts used for hydrogen production from water under solar irradiation. This objective is achieved by applying the first principles computational approach to reveal relationship among compositions of materials under consideration, their electronic structure and catalytic activity. A major part of the work is focused on electro-catalysts for hydrogen fuel cells. Platinum (Pt) is widely used in the electrodes of fuel cells due to its good catalytic …

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Inverse Problems In Multiple Light Scattering, John Broky Jan 2013

Inverse Problems In Multiple Light Scattering, John Broky

Electronic Theses and Dissertations

The interaction between coherent waves and material systems with complex optical properties is a complicated, deterministic process. Light that scatters from such media gives rise to random fields with intricate properties. It is common perception that the randomness of these complex fields is undesired and therefore is to be removed, usually through a process of ensemble averaging. However, random fields emerging from light matter interaction contain information about the properties of the medium and a thorough analysis of the scattered light allows solving specific inverse problems. Traditional attempts to solve these kinds of inverse problems tend to rely on statistical …

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Reduced Susceptibility Of Deformation Due To Vibrational And Gravitational Effects On A Focus Variable Adaptive Lens, Victoriya Relina Jan 2013

Reduced Susceptibility Of Deformation Due To Vibrational And Gravitational Effects On A Focus Variable Adaptive Lens, Victoriya Relina

Electronic Theses and Dissertations

Orthodox optical devices, such as lenses, mirrors, and prisms, are composed of solidstate materials, which although well studied and implemented ubiquitously are severely limited in their adaptable properties. An arguably new field of adaptive optics has emerged to further expand photonic manipulation competences of optical components. Fluid-based adaptive optical components were introduced as early as 1968 [1]; such components have the ability to change the shape of their interface surface, thus allowing for a variable curvature profile. The method of manipulation varies greatly, as does the range of surface deformations. A solid-state optical component is affected by system vibration variation …

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Mechanochemistry For Solid-State Syntheses And Catalysis, David Restrepo Jan 2013

Mechanochemistry For Solid-State Syntheses And Catalysis, David Restrepo

Electronic Theses and Dissertations

Traditional methods of synthesizing inorganic materials, such as hydrothermal, sol-gel, calcination and grinding steps, can typically require use of high temperatures, expensive precursors or use of solvents. Because of the energy-intensive nature or environmental impact these techniques, there is a push, especially from an industrial perspective, to move towards greener approaches. Mechanochemistry is a solvent-free alternative technique that can be used to synthesize a variety of materials under ambient conditions. Due to this, there is an increase in attention towards the use of this approach in both solid-state inorganic and organic chemistry. This dissertation reports the mechanochemical synthesis of a …

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Biogeography And Systematics Of The Nerodia Clarkii/Nerodia Fasciata Clade In Florida, Gregory Territo Jan 2013

Biogeography And Systematics Of The Nerodia Clarkii/Nerodia Fasciata Clade In Florida, Gregory Territo

Electronic Theses and Dissertations

Biogeography provides a window into the evolutionary history of populations, and helps explain the diversity and distribution of life through time. Viewed from a systematic perspective, biogeographic studies generate convincing arguments to explain the relationships among organisms and categorize them into useful taxonomies. When taxonomies do not reflect evolutionary histories, inaccurate representations of biodiversity confound future studies and conservation efforts. Two thamnophiine snakes, Nerodia clarkii and Nerodia fasciata, harbor unique morphological and ecological adaptations that obscured natural groupings, leading to controversial taxonomic delimitations. Additionally, population declines documented in N. clarkii compressicauda and N. clarkii taeniata led managers to list N. …

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An Exploratory Study Of Customer Vulnerability: A Cross-Segment Approach, Taryn Aiello Jan 2013

An Exploratory Study Of Customer Vulnerability: A Cross-Segment Approach, Taryn Aiello

Electronic Theses and Dissertations

The purpose of this study is to explore the concept of customer vulnerability across varying service industries. While the concept of customer vulnerability has been debated in business, marketing, sociology, and psychology scholarly literature, there has been little research conducted that specifically investigates consumers’ perceptions of vulnerability during the service exchange. Specific to this research, customer vulnerability is defined as experiences in which consumers participate in a service exchange with a firm during a time of individual or shared medical, physical, emotional, or spiritual necessity, whether the vulnerability is experienced during the course of the transaction or whether consumers arrive …

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An Event-Related Potential Investigation Of Error Monitoring In Adults With A History Of Psychosis, Chi Chan Jan 2013

An Event-Related Potential Investigation Of Error Monitoring In Adults With A History Of Psychosis, Chi Chan

Electronic Theses and Dissertations

Metacognition, which involves monitoring and controlling of one’s thoughts and actions, is essential for guiding behavior and organization of information. Deficits in self-monitoring have been suggested to lead to psychosis and poor functional outcome. Abnormalities in eventrelated potentials originating from the anterior cingulate cortex (ACC), a brain region associated with error detection, have been consistently reported in individuals with schizophrenia during error monitoring tasks. This study sought to examine whether these abnormalities are present in individuals with a history of psychosis across diagnostic categories and whether they are associated with subjective appraisal of self-performance and personality traits related to psychosis. …

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