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A Comparative Analysis of Digital and Paper Restaurant Menus Based on Customer Perception and Nutritional Labeling
The restaurant industry is a highly customer-driven field. Therefore, it is imperative that restaurateurs consider customer expectations with regard to restaurant menus. The purpose of this experimental study is to examine the effects of menu format (i.e., paper or digital) and amount of nutritional information (i.e., extensive, brief, or none) on customer perceptions of the effectiveness, perceived ease of use, and information quality of the menu. Furthermore, this research intends to test the effect of these three menu attributes on the outcomes of value and satisfaction in order to assess the competitive advantage of one format over the other. The Cognitive Appraisal and Information Processing Theories provide structure to the proposed conceptual framework and give credence to the findings. This study also fills gaps in the present research by not only ameliorating weaknesses of extant studies, but also by examining several different aspects of restaurant menus simultaneously within a single study.
The Walling Family of Nineteenth-Century Texas: An Examination of Movement and Opportunity on the Texas Frontier
The Walling Family of Nineteenth-Century Texas recounts the actions of the first four generations of the John Walling family. Through a heavily quantitative study, the study focuses on the patterns of movement, service, and seizing opportunity demonstrated by the family as they took full advantage of the benefits of frontier expansion in the Old South and particularly Texas. In doing so, it chronicles the role of a relatively unknown family in many of the most defining events of the nineteenth-century Texas experience such as the Texas Revolution, Mexican War, Civil War, Reconstruction, and the Close of the Frontier. Based on extensive research in census, tax, election, land, military, family paper, newspaper, and existing genealogical records; the study documents the contributions of family members to the settlement of more than forty counties while, at the same time, noting its less positive behaviors such as its open hostility to American Indians, and significant slave ownership. This study seeks to extend the work of other quantitative studies that looked at movement and political influence in the Old South, Texas, and specific communities to the microcosm of a single extended family. As a result, it should be of use to those wanting a greater understanding of how events in nineteenth-century Texas shaped, and were shaped by, families outside the political and social elite.
Can Observing Behavior Predict Performance in Conditional Discriminations?
Prompts are implemented often in training procedures, to include conditional discriminations, and this can lead to prompt dependency. The current study extends a prior study that suggested that the effectiveness of supplementary visual stimuli displaying the sample and comparison was dependent on the timing in relation to the selection task, presented as a prompt or feedback, in a match-to-sample procedure. The current research examines if the differences in that effectiveness were due to differences in observing behavior in those two conditions. Measures of observing behavior were determined by making access to the individual visual stimuli contingent on clicking on the visual stimulus and keeping the cursor located on the stimulus. Participants viewed the sample comparison much less than the comparison stimulus in both the prompt and feedback conditions. Latency to select the comparison stimulus was much shorter for the prompt condition suggesting that the participants might have interacted differently with the selection task in the two conditions.
Effects of Brain Brain Injury on Primary Cilia of Glial Cells and Pericytes
Glial cells maintain homeostasis that is essential to neuronal function. Injury to the nervous system leads to the activation and proliferation of glial cells and pericytes, which helps to wall off the damaged region and restore homeostatic conditions. Sonic hedgehog is a mitogen which is implicated in injury-induced proliferation of glial cells and pericytes. The mitogenic effects of sonic hedgehog require primary cilia, but the few reports on glial or pericyte primary cilia do not agree about their abundance and did not address effects of injury on these cilia. Primary cilia are microtubule-based organelles that arise from the centrosome and are retracted before cells divide. Depending on cell type, proteins concentrated in cilia can transduce several mitotic, chemosensory, or mechanosensory stimuli. The present study investigated effects of stab wound injury on the incidence and length of glial and pericyte primary cilia in the area adjacent to the injury core. Astrocytes, polydendrocytes and pericytes were classified by immunohistochemistry based on cell-type markers. In normal adult mice, Arl13b immunoreactive primary cilia were present in a majority of each cell type examined: astrocytes, 98±2%; polydendrocytes, 87±6%; and pericytes, 79±13% (mean ± SEM). Three days post-injury, cilium incidence decreased by 24% in astrocytes (p< 0.008) and 41% in polydendrocytes (p< 0.002), but there was no significant effect in pericytes. Polydendrocytes labeled with the cell cycle marker Ki67 were less likely to have cilia compared to resting, Ki67- polydendrocytes. Considering post-injury rates of proliferation for astrocytes and polydendrocytes, it appears that resorption of cilia due to cell cycle entry may account for much of the loss of cilia in polydendrocytes but was not sufficient to account for the loss of cilia in astrocytes. Under normal conditions, astrocytes rarely divide, and they maintain non-overlapping territories. However, three days after injury, there was a 7-fold increase in ...
Enhanced Coarse-Graining for Multiscale Modeling of Elastomers
One of the major goal of the researchers is to reduce energy loss including nanoscale to the structural level. For instance, around 65% of fuel energy is lost during the propulsion of the automobiles, where 11% of the loss happens at tires due to rolling friction. Out of that tire loss, 90 to 95% loss happens due to hysteresis of tire materials. This dissertation focuses on multiscale modeling techniques in order to facilitate the discovery new rubber materials. Enhanced coarse-grained models of elastomers (thermoplastic polyurethane elastomer and natural rubber) are constructed from full-atomic models with reasonable repeat units/beads associated with pressure-correction for non-bonded interactions of the beads using inverse Boltzmann method (IBM). Equivalent continuum modeling is performed with volumetric/isochoric loading to predict macroscopic mechanical properties using molecular mechanics (MM) and molecular dynamics (MD). Glass-transition and rate-dependent mechanical properties along with hysteresis loss under uniaxial deformation is predicted with varying composition of the material. A statistical non-Gaussian treatment of a rubber chain is performed and linked with molecular dynamics in order predict hyperelastic material constants without fitting with any experimental data.
Black Males' Treatment Experiences in Mental Health Court: A Phenomenological Analysis
Mental health courts (MHCs) are part of an umbrella of specialty courts in which court officials, law enforcement, and treatment providers work together to seek alternative solutions to failed traditional approaches to justice. Researchers investigating MHCs indicated that the courts may be helpful in reducing recidivism and introducing offenders with mental health disorders to treatment services. I used the qualitative method of phenomenology to understand the experiences of young adult Black male clients' perceptions of mental health treatment in MHCs. Twelve participants ranged in age from 21-40 years. The research team identified three themes -- (a) helpful treatment factors, (b) relational growth, (c) treatment barriers – and five subthemes: (a) internal growth, (b) relational growth, (c) behavioral growth, (d) factors of marginalization, and (e) interpersonal barriers. Meaning pertaining to findings and implications for research and practice are discussed.
Memory and Continuity Amidst Irreversible Decline in the Texas Big Empty
This thesis interrogates sense of place and place attachment in the Big Empty on the north central Texas plains. The region stretches from the Red River on the north to the Colorado River basin on the south and from the Cross Timbers on the east to the Caprock escarpment on the west. Since 1930, the Big Empty has seen sustained and severe population decline such that some counties there now register less than a quarter the population they did at their peaks during the interwar years. Through in-depth field interviews, I examine sense of place and place attachment amidst apparently irreversible decline. I also describe conditions of postindustrial rurality arising from rolling reconfigurations of economic and social relations, particularly changes in scale in farming and the diminished centrality of productivist agriculture in local economies and culture, and how these conditions become legible through the study of place.
Clocks and Mirrors
The essays featured in this collection highlight the gaps, as well as parallels, between mental illness and the human condition. In "Appearances," the narrator struggles with her own visual identity especially after reflecting on her Mom's own lengthy history with the mirror. In "Migrations," the lyrical voice of the narrator carries the reader through the typical day of a clinically depressed female character. Lastly, "Attempting the Fall," addresses the issues society has with mental illness by following the narrator from her suicide attempt to the mental ward.
Angular Analysis of a Wide-Band Energy Harvester based on Mutually Perpendicular Vibrating Piezoelectric Beams
The recent advancements in electronics and the advents of small scaled instruments has increased the attachment of life and functionality of devices to electrical power sources but at the same time granted the engineers and companies the ability to use smaller sources of power and batteries. Therefore, many scientists have tried to come up with new solutions for a power alternatives. Piezoelectric is a promising material which can readily produce continuous electric power from mechanical inputs. However, their power output is dependent upon several factors such as, system natural frequency, their position in the system, the direction of vibration and many other internal and external factors. In this research the working bandwidth of the system is increased through utilizing of two different piezoelectric beam in different directions. The dependency of output power with respect to rotation angle and also the frequency shift due to the rotation angle is studied.
Programmable Mechanical Metamaterials with Negative Poisson's Ratio and Negative Thermal Expansion
Programmable matter is a material whose properties can be programmed to achieve particular shapes or mechanical properties upon command. This is an essential technique that could one day lead to morphing aircraft and ground vehicles. Metamaterials are the rationally designed artificial materials whose properties are not observed in nature. Their properties are typically controlled by geometry rather than chemical compositions. Combining metamaterials with a programmable function will create a new area in the intelligent material design. The objective of this study is to design and demonstrate a tunable metamaterial and to investigate its thermo-mechanical behavior. An integrated approach to the metamaterial design was used with analytical modeling, numerical simulation, and experimental demonstration. The dynamic thermo-mechanical analysis was used to measure base materials' modulus and thermal expansion coefficient as a function of temperature. CPS, the unit cell of the metamaterial, is composed of circular holes and slits. By decomposing kinematic rotation of the arm and elastic deformation of a bi-material hinge, thermo-mechanical constitutive models of CPS were developed and it was extended to 3D polyhedral structures for securing isotropic properties. Finite element based numerical simulations of CPS and polyhedral models were conducted for comparison with the analytical model. 3D printing of multi-materials was used for sample fabrication followed by tests with uniaxial compressive mechanical tests and thermal tests at 50℃. From the analytical model of the metamaterial, the contour plots were obtained for the effective properties – Poisson's ratio, the effective coefficient of thermal expansion of the metamaterial as a function of geometry and materials. A controllable range of temperature and strain was identified associated with maximized thermal expansion mismatch and contact on the slit surface of CPS, respectively. This work will pave the road toward the design of programmable metamaterials with both mechanically- and thermally- tunable capability and provide unique ...
Information Content of Iron Butterfly Arbitrage Bounds
Informed traders trade options on underlying securities to lower transaction costs and increase financial leverage for price trend and variance strategies. Options markets play a significant role in price discovery by incorporating private information about future prices for an underlying security into option prices. I generate a new model-free volatility measure to calculate the "distance from arbitrage bounds" from minute-by-minute option series for the S&P 500 index and 30 individual underlying stocks. These iron butterfly arbitrage bounds (IBBs) use intraday call and put option prices from the Bloomberg database. Narrow and wide IBBs are expected to reveal the options market valuation of volatility by market participants. Data series is gathered by using successive one-minute intervals from the Bloomberg database. The data comprise the most recent bid and ask option prices and volumes. I collect S&P 500 index values and index options and use 30 underlying stock prices and option prices for the contracts that have the largest option trading volume during the sampling interval. These bid and ask prices reflect the information generated by intraday price pressures implied by S&P 500 index options or stock options. Consistent with the option micro-structure literature, I find that the IBB measure for actively traded stock options attains its highest level immediately after the open of the market, declines steadily throughout the first trading hour and remains relatively stable until market close. However, index IBBs behave differently. S&P 500 index option IBB attains its lowest level during the first hour of the trading day, then increases and remains relatively stable until market close. I present new evidence regarding the dynamic relation between stock returns and innovations in expected volatility by using the minute-by-minute change in implied volatility (IV) as a proxy. Unlike the relationship between individual stock returns and their respective changes in implied ...
The Castle/Nikki Heat Phenomenon: A Detailed Examination of Female Representation in Entertainment Media
As entertainment reflects a culture's ideology, it is important for researchers to study its messages and subsequently its potential meanings. Entertainment has the power to inform and persuade, creating models for behavior with which the public interacts. The entertainment texts for the purpose of this study are the Castle television series and the Nikki Heat novels. Together, they create a unique multi-layer fictional world. By using postmodern, feminist, communication, and entertainment theories, the results of this study provide a tightly focused lens which views a narrow aspect of entertainment media. Each text was thoroughly examined using textual analysis, Feminist Poststructuralist Discourse Analysis, and conversation analysis. Contrary to expectations, the results indicated that the Castle and Nikki Heat texts support hegemonic ideology, particularly through the use of exaggerated stereotypes, strict gender roles, imagery, and narrative choices that help perpetuate rape culture. The discussion outlines how these results can be interpreted through the dominant messages presented in the texts. This research is intended to serve as a foundation for future research regarding entertainment media.
Friends of the State Courts: Organized Interests and State Courts of Last Resort
Why do interest groups participate in state courts of last resort by filing amicus curiae briefs? Are they influential when they do? This dissertation examines these questions using an original survey of organized interests that routinely participate in state supreme courts, as well as data on all amicus curiae briefs and majority opinions in over 14,000 cases decided in all fifty-two state supreme courts for a four year period. I argue that interest groups turn to state judiciaries to achieve the dual goals of influencing policy and organizational maintenance, as amicus briefs can help organized interests achieve both outcomes. Furthermore, I contend that amicus briefs are influential in shaping judicial policy-making through the provision of legally persuasive arguments. The results suggest that interest groups do file amicus briefs to both lobby for their preferred policies and to support their organization's long-term viability. Additionally, the results indicate that organized interests also participate in counteractive lobbying in state courts of last resort by filing amicus briefs to ensure their side is represented and to dull the effect of oppositional amici. The findings also demonstrate support for the influence of amicus briefs on judicial policy-making on state high courts, as amicus briefs can influence the ideological direction of the court's majority opinions. Overall, this research extends our understanding of interest group lobbing in the judiciary and in state policy venues, and provides insight into judicial politics and policy-making on state courts of last resort.
Examining the Impact of the Community of Inquiry and Student Learning Process on Participants' Academic Achievement
This dissertation presents an empirical investigation of learning from online courses. The current dissertation examined student participation, using Arbaugh et al.'s Community of Inquiry (CoI) survey instrument and Biggs et al.'s revised version of the Study Process Questionnaire (R-SPQ-2F) to determine CoI influences on learning from the students' perspective. This study is in response to Rourke and Kanuka's call to provide further empirical evidence about CoI conceptual framework connections to deep and meaningful learning. The purpose of this study was to examine the impact of the elements of CoI, cognitive, social, and teaching presences and students' learning approaches to students' perceived learning. Students enrolled in traditional, online, and, blended courses during the 2016 spring semester at a southwestern university participated in a web-based survey. Structural equation modeling was used to test the indirect effects between the elements of CoI, learning approaches, and perceived learning. Student's deep approach to learning was found to have an indirect effect between cognitive presence and perceived learning. However, this study's findings, when the CoI framework was viewed in its entirety, failed to provide evidence to simulate deep and meaningful learning.
Privacy Preserving EEG-based Authentication Using Perceptual Hashing
The use of electroencephalogram (EEG), an electrophysiological monitoring method for recording the brain activity, for authentication has attracted the interest of researchers for over a decade. In addition to exhibiting qualities of biometric-based authentication, they are revocable, impossible to mimic, and resistant to coercion attacks. However, EEG signals carry a wealth of information about an individual and can reveal private information about the user. This brings significant privacy issues to EEG-based authentication systems as they have access to raw EEG signals. This thesis proposes a privacy-preserving EEG-based authentication system that preserves the privacy of the user by not revealing the raw EEG signals while allowing the system to authenticate the user accurately. In that, perceptual hashing is utilized and instead of raw EEG signals, their perceptually hashed values are used in the authentication process. In addition to describing the authentication process, algorithms to compute the perceptual hash are developed based on two feature extraction techniques. Experimental results show that an authentication system using perceptual hashing can achieve performance comparable to a system that has access to raw EEG signals if enough EEG channels are used in the process. This thesis also presents a security analysis to show that perceptual hashing can prevent information leakage.
Design and Manufacture of Molding Compounds for High Reliability Microelectronics in Extreme Conditions
The widespread use of electronics in more avenues of consumer use is increasing. Applications range from medical instrumentation that directly can affect someone's life, down hole sensors for oil and gas, aerospace, aeronautics, and automotive electronics. The increased power density and harsh environment makes the reliability of the packaging a vital part of the reliability of the device. The increased importance of analog devices in these applications, their high voltage and high temperature resilience is resulting in challenges that have not been dealt with before. In particular packaging where insulative properties are vital use polymer resins modified by ceramic fillers. The distinct dielectric properties of the resin and the filler result in charge storage and release of the polarization currents in the composite that have had unpredictable consequences on reliability. The objective of this effort is therefore to investigate a technique that can be used to measure the polarization in filled polymer resins and evaluate reliable molding compounds. A valuable approach to measure polarization in polymers where charge release is tied to the glass transition in the polymer is referred to as thermally stimulated depolarization current (TSDC) technique. In this dissertation a new TSDC measurement system was designed and fabricated. The instrument is an assembly of several components that are automated via a LabVIEW program that gives the user flexibility to test different dielectric compounds at high temperatures and high voltage. The temperature control is enabled through the use of dry air convection heating at a very slow rate enabling controlled heating and cooling. Charge trapping and de-trapping processes were investigated in order to obtain information on insulating polymeric composites and how to optimize it. A number of material properties were investigated. First, polarization due to charges on the filer were investigated using composites containing charged and uncharged particles using ...
Family and Cultural Influences on Latino Emerging Adults' Career Development
There is an extensive amount of research on career development, but most of the constructs studied have focused on content-oriented variables rather than process-oriented variables. While some of the studies have examined samples from ethnic minority populations, the majority of studies use ethnic minority populations as comparison groups, studying between-group differences as opposed to within-group differences. The literature is especially deficient in the are of Latino career development. The current study will examine how family and culture influence the career development of Latino emerging adults. This study will explore the influence of socioeconomic status and acculturation on the career salience and career maturity of Latino emerging adults. The quality of the parent-emerging adult relationship will also be explored for its influence on career development outcomes in this population. One hundred fifty Latino undergraduate students ages 18-24 will be recruited for participation in this study. The participants will complete questionnaires regarding demographic information, acculturation, the quality of the parent-emerging adult relationship, career salience, and career maturity.
Modeling of Hexagonal Boron Nitride Filled Bismalemide Polymer Composites for Thermal and Electrical Properties for Electronic Packaging
Due to the multi-tasking and miniaturization of electronic devices, faster heat transfer is required from the device to avoid the thermal failure. Die-attached polymer adhesives are used to bond the chips in electronic packaging. These adhesives have to hold strong mechanical, thermal, dielectric, and moisture resistant properties. As polymers are insulators, heat conductive particles are inserted in it to enhance the thermal flow with an attention that there would be no electrical conductivity as well as no reduction in dielectric strength. This thesis focuses on the characterization of polymer nanocomposites for thermal and electrical properties with experimental and computational tools. Platelet geometry of hexagonal boron nitride offers highly anisotropic properties. Therefore, their alignment and degree of orientation offers tunable properties in polymer nanocomposites for thermal, electrical, and mechanical properties. This thesis intends to model the anisotropic behavior of thermal and dielectric properties using finite element and molecular dynamics simulations as well as experimental validation.
Parcel-Based Change Detection Using Multi-Temporal LiDAR Data in the City of Surrey, British Columbia, Canada
Change detection is amongst the most effective critical examination methods used in remote sensing technology. In this research, new methods are proposed for building and vegetation change detection using only LiDAR data without using any other remotely sensed data. Two LiDAR datasets from 2009 and 2013 will be used in this research. These datasets are provided by the City of Surrey. A Parcel map which shows parcels in the study area will be also used in this research because the objective of this research is detecting changes based on parcels. Different methods are applied to detect changes in buildings and vegetation respectively. Three attributes of object –slope, building volume, and building height are derived and used in this study. Changes in buildings are not only detected but also categorized based on their attributes. In addition, vegetation change detection is performed based on parcels. The output shows parcels with a change of vegetation. Accuracy assessment is done by using measures of completeness, correctness, and quality of extracted regions. Accuracy assessments suggest that building change detection is performed with better results.
Dissimilar Joining of Al (AA2139) – Mg (WE43) Alloys Using Friction Stir Welding
This research demonstrates the use of friction stir welding (FSW) to join dissimilar (Al-Mg) metal alloys. The main challenges in joining different, dissimilar metal alloys is the formation of brittle intermetallic compounds (IMCs) in the stir zone affecting mechanical properties of joint significantly. In this present study, FSW joining process is used to join aluminum alloy AA2139 and magnesium alloy WE43. The 9.5 mm thick plates of AA2139 and WE43 were friction stir butt welded. Different processing parameters were used to optimize processing parameters. Also, various weldings showed a crack at interface due to formation of IMCs caused by liquation during FSW. A good strength sound weld was obtained using processing parameter of 1200 rev/min rotational speed; 76.2 mm/min traverse speed; 1.5 degree tilt and 0.13 mm offsets towards aluminum. The crack faded away as the tool was offset towards advancing side aluminum. Mostly, the research was focused on developing high strength joint through microstructural control to reduce IMCs thickness in Al-Mg dissimilar weld joint with optimized processing parameter and appropriate tool offset.
Modeling Cognitive Authority Relationships
Information-seeking behavior is a mixture of activities and attitudes, oftentimes motivated by an individual's need to make a decision. One underlying element of this mixture is cognitive authority - which sources (e.g., individuals, institutions, texts, etc.) can be trusted to fulfil the information needs? In order to gain insight into the dynamics of cognitive authority selection behavior which is an information seeking behavior, this study explored primary source text data (316 text records) that reflected selection in the mundaneness of life (advice column submissions and responses). Linguistic analysis was performed on the data using the Linguistic Inquiry Word Count (LIWC2015) software package. Pearson correlation and 1-sample T tests revealed the same 45 statistically significant relationships (SSRs) in the word usage behavior of all subgroups. As a result of the study, the gap in research formed from the lack of quantitative models of cognitive authority relationships was addressed via the development of the Wordprint Classification System which was used to generate a cognitive authority relationship model in the form of a cognitive authority intra-segment wordprint. The findings and implications of this study may provide a contribution to the body of work in the area of information literacy and information seeker behavior by revealing factors that information scientists can address to help meet information seekers' needs. Additionally, the Wordprint Classification System may be used in such disciplines as psychology, marketing, and forensic linguistics to create to create models of various relationships or individuals through the use of written or spoken word usage patterns.
Revisiting the Nineteenth-Century Poe Controversies
This article reviews the book "Poe in His Own time: A Biographical Chronicle of his Life, Drawn from Recollections, Interviews, and Memoirs by Family, Friends, and Associates," edited by Benjamin F. Fisher, published by the University of Iowa Press, 2010.
Compostable Soy-Based Polyurethane Foam with Kenaf Core Modifiers
Building waste and disposable packaging are a major component in today's landfills. Most of these are structural or thermally insulative polymer foams that do not degrade over a long period of time. Currently, there is a push to replace these foams with thermoplastic or biodegradable foams that can either be recycled or composted. We propose the use of compostable soy-based polyurethane foams (PU) with kenaf core modifiers that will offer the desired properties with the ability to choose responsible end-of-life decisions. The effect of fillers is a critical parameter in investigating the thermal and mechanical properties along with its effect on biodegradability. In this work, foams with 5%, 10%, and 15% kenaf core content were created. Two manufacturing approaches were used: the free foaming used by spray techniques and the constrained expansion complementary to a mold cavity. Structure-property relations were examined using differential scanning calorimetry (DSC), dynamic mechanical analysis (DMA), thermal conductivity, compression values, scanning electron microscopy (SEM), x-ray micro-computed tomography (micro-CT), and automated multiunit composting system (AMCS). The results show that mechanical properties are reduced with the introduction of kenaf core reinforcement while thermal conductivity and biodegradability display a noticeable improvement. This shows that in application properties can be improved while establishing a responsible end-of-life choice.
Decision-Making with Big Information: The Relationship between Decision Context, Stopping Rules, and Decision Performance
Ubiquitous computing results in access to vast amounts of data, which is changing the way humans interact with each other, with computers, and with their environments. Information is literally at our fingertips with touchscreen technology, but it is not valuable until it is understood. As a result, selecting which information to use in a decision process is a challenge in the current information environment (Lu & Yuan, 2011). The purpose of this dissertation was to investigate how individual decision makers, in different decision contexts, determine when to stop collecting information given the availability of virtually unlimited information. Decision makers must make an ultimate decision, but also must make a decision that he or she has enough information to make the final decision (Browne, Pitts, & Wetherbe, 2007). In determining how much information to collect, researchers found that people engage in ‘satisficing' in order to make decisions, particularly when there is more information than it is possible to manage (Simon, 1957). A more recent elucidation of information use relies on the idea of stopping rules, identifying five common stopping rules information seekers use: mental list, representational stability, difference threshold, magnitude threshold, and single criterion (Browne et al., 2007). Prior research indicates a lack of understanding in the areas of information use (Prabha, Connaway, Olszewski, & Jenkins, 2007) and information overload (Eppler & Mengis, 2004) in Information Systems literature. Moreover, research indicates a lack of clarity in what information should be used in different decision contexts (Kowalczyk & Buxmann, 2014). The increase in the availability of information further complicates and necessitates research in this area. This dissertation seeks to fill these gaps in the literature by determining how information use changes across decision contexts and the relationships between stopping rules. Two unique methodologies were used to test the hypotheses in the conceptual ...
Friction Stir Welding of High Strength Precipitation Strengthened Aluminum Alloys
Rising demand for improved fuel economy and structural efficiency are the key factors for use of aluminum alloys for light weighting in aerospace industries. Precipitation strengthened 2XXX and 7XXX aluminum alloys are the key aluminum alloys used extensively in aerospace industry. Welding and joining is the critical step in manufacturing of integrated structures. Joining of precipitation strengthened aluminum alloys using conventional fusion welding techniques is difficult and rather undesirable in as it produces dendritic microstructure and porosities which can undermine the structural integrity of weldments. Friction stir welding, invented in 1991, is a solid state joining technique inherently benefitted to reduces the possibility of common defects associated with fusion based welding techniques. Weldability of various 2XXX and 7XXX aluminum alloys via friction stir welding was investigated. Microstructural and mechanical property evolution during welding and after post weld heat treatment was studied using experimental techniques such as transmission electron microscopy, differential scanning calorimetry, hardness testing, and tensile testing. Various factors such as peak welding temperature, cooling rate, external cooling methods (thermal management) which affects the strength of the weldment were studied. Post weld heat treatment of AL-Mg-Li alloy produced joint as strong as the parent material. Modified post weld heat treatment in case of welding of Al-Zn-Mg alloy also resulted in near 100% joint efficiency whereas the maximum weld strength achieved in case of welds of Al-Cu-Li alloys was around 80-85% of parent material strength. Low dislocation density and high nucleation barrier for the precipitates was observed to be responsible for relatively low strength recovery in Al-Cu-Li alloys as compared to Al-Mg-Li and Al-Zn-Mg alloys.
Dimensions of Acculturation and Sexual Health among U.S. Hispanic Youth
Hispanic youth living in the U.S. share a disproportionate burden of risk for HIV, other STIs, and teen pregnancies. They also tend to report lower rates of condom use and higher rates of inconsistent condom use than other racial/ethnic groups. Furthermore, immigrant Hispanic adolescents experience a unique burden of sexual risk compared to their non-immigrant counterparts. These negative sexual health outcomes can severely derail the overall health, social mobility, and life opportunities of these adolescents. Social researchers have tried to explain these sexual risk disparities using the concept of immigrant acculturation, which is broadly defined as the process of adopting the cultural values and beliefs of a host society. Immigrant acculturation has been shown to play a key role in shaping youth attitudes and behaviors, including sexual risk behaviors (see Lee & Hahm, 2010). Yet, studies have largely overlooked the contextual components of acculturation that have been proposed in theoretical literature, specifically characteristics of the immigrant's receiving community. Furthermore, studies have not adequately explored the influence of acculturation on two crucial measures of sexual risk: teen pregnancy norms and condom use. Therefore, the current dissertation consists of two unique studies that examine the influence of acculturation, at both the individual and neighborhood level, on Hispanic adolescent teen pregnancy norms and condom use over time. The aim is to fill these important gaps in the literature and expand on earlier explanations of the relationship between cultural, place, and long-term sexual health. Both studies use nationally-representative data from the National Longitudinal Study of Adolescent to Adult Health. Overall, findings suggest an immigrant advantage for both teen pregnancy norms and condom use, although this advantage functions differently for males and females. Furthermore, the studies demonstrate the importance of including contextual measures of acculturation into studies related to Hispanic adolescent sexual health.
Effect Size Reporting and Interpreting Practices in Published Higher Education Journal Articles
Data-driven decision making is an integral part of higher education and it needs to be rooted in strong methodological and statistical practices. Key practices include the use and interpretation of effect sizes as well as a correct understanding of null hypothesis significance testing (NHST). Therefore, effect size reporting and interpreting practices in higher education journal articles represent an important area of inquiry. This study examined effect size reporting and interpretation practices of published quantitative studies in three core higher education journals: Journal of Higher Education, Review of Higher Education, and Research in Higher Education. The review covered a three-year publication period between 2013 and 2015. Over the three-year span, a total of 249 articles were published by the three journals. The number of articles published across the three years did not vary appreciably. The majority of studies employed quantitative methods (71.1%), about a quarter of them used qualitative methods (25.7%), and the remaining 3.2% used mixed methods. Seventy-three studies were removed from further analysis because they did not feature any quantitative analyses. The remaining 176 quantitative articles represented the sample pool. Overall, 52.8% of the 176 studies in the final analysis reported effect size measures as part of their major findings. Of the 93 articles reporting effect sizes, 91.4% of them interpreted effect sizes for their major findings. The majority of studies that interpreted effect sizes also provided a minimal level of interpretation (60.2% of the 91.4%). Additionally, 26.9% of articles provided average effect size interpretation, and the remaining 4.3% of studies provided strong interpretation and discussed their findings in light of previous studies in their field.
Cooperative Strategy and Sources of Knowledge Integration Capability and Innovation: A Relational View
Faced with the challenges to addressing the novelties of the changing business environments (e.g., new customer requirement, changes in customers taste and preferences, the introduction of new products or services by competitors), organizations seek to build collaboration among their employees who possess complementary knowledge. Integrating complementary knowledge enhances employees' ability to address environmental challenges and foster innovation. Despite the importance of knowledge integration for innovation, integration of such knowledge becomes difficult when employees lack a shared understanding of knowledge, and when the knowledge is newly generated. Because new knowledge is tacit in nature and highly personal to a particular individual, it is difficult to articulate, making knowledge integration (KI) an arduous task. Lack of shared understanding, the presence of new knowledge, and lack of common interests in employees creates three types of knowledge boundaries – syntactic (information processing) boundaries, semantic (interpretive) boundaries, and pragmatic (political) boundaries. The presence of knowledge boundaries makes it difficult for employees to share and access their knowledge with each other. To overcome the challenges related to the knowledge boundaries, employees use boundary-spanning objects, which are common lexicons, common meaning, and common interests, to share and access their knowledge across the boundaries. Although prior studies have emphasized the importance of knowledge integration of various knowledge sources for innovations, examinations of what enhances KI capability of employees for organizational innovation remain limited. In addition, apart from Carlile, (2004) and Franco (2013), which are both case studies, other studies that examine the role of boundary spanning objects for knowledge integration are missing. The knowledge management literature also fails to measures (the success of common lexicons, common meaning, and common interests for achieving KI capability) boundary spanning objects. Therefore, in this study, new measurement items of boundary spanning objects and novelty are developed to test the hypotheses. A survey-based ...
Can Imagination Travel the Distance? Investigating the Role of Psychological Distance and Construal Level in Consumers' Elaborative Approach
Much of consumer behavior research focuses on how consumers process and evaluate information to make current decision. In contrast, many consumer choices ares are underpinned by the need to make choices that incorporate the past or future, other places, other people and other situations that are seemingly hypothetical. The imagination provides the chief means by which consumers are able to traverse this psychological distance. Construal Level Theory (CLT) explains how individuals are able to plan for the future, consider the perspective of another individual and even consider situations that are counter to reality. Construal mindsets are enacted when people form mental representations of distant objects, people, or places. In abstract construal mindsets, individuals think generally, in terms of global features of an object, person, or situation. On the other hand, concrete construal mindsets center around the detailed aspects of an object, person, or situation. These two different construal mindsets serve to help people cope with the uncertainty of the future. This is because abstract cosntruals are more likely than concrete construals to remain unchanged as distance from a future object, person, or place reduces. A number of consumer behavior settings require the use of the imagination. Sticking to a weight loss and or fitness plan, planning a vacation trip, saving for retirement and imagining what birthday gift a friend will enjoy all require imagining a psychologically distant state. Marketers generally seek to stimulate consumption by requiring consumers to imagine a consumption setting. This dissertation uses CLT to guide the hypotheses, as CLT explains how individuals deal with psychological distance by adopting a construal mindset. CLT explains differences in information processing associated with adopting a specific construal mindset and suggests how construal mindsets impact consumer information elaboration processes. This study will contribute to CLT by addressing an understudied be related area: ...
Eight-Year Course of Cognitive Functioning in Bipolar Disorder with Psychotic Features
The purpose of the current study was to examine neuropsychological functioning in patients with bipolar disorder (BD) with psychotic features. Data from a large, epidemiological study of patients with first-episode psychosis was used to examine verbal learning and working memory 10 years after onset of psychosis in patients with BD relative to patients with schizophrenia (SZ) and patients with psychotic major depressive disorder (MDD). Cross-sectional comparisons of verbal learning and working memory at the 10-year follow-up mirrored findings of relative performance at the 2-year follow-up (Mojtabai, 2000), as patients with SZ performed significantly worse than patients with psychotic affective disorders. When FEP patients' cognitive performance was examined longitudinally, all groups showed non-significant decline over time, with no significant diagnostic group differences after accounting for current symptoms. More frequent hospitalizations and longer treatment with antipsychotics were associated with poorer performance on cognitive testing 10 years after illness onset, but these associations disappeared when controlling baseline cognitive performance. Within the BD sample, current positive and negative psychotic symptoms were associated with poorer performance on cognitive testing. After controlling for baseline cognitive performance, markers of clinical course were unrelated to cognitive performance, consistent with existing literature on longitudinal cognitive functioning in patients with BD. The current findings support a neurodevelopmental model of verbal learning and working memory deficits in patients with bipolar disorder.
Market Efficiency, Arbitrage and the NYMEX Crude Oil Futures Market
Since Engle and Granger formulated the concept of cointegration in 1987, the literature has extensively examined the unbiasedness of the commodity futures prices using the cointegration-based technique. Despite intense attention, many of the previous studies suffer from the contradicting empirical results. That is, the cointegration test and the stationarity test on the differential contradict each other. In marked contrast, my dissertation develops the no-arbitrage cost-of-carry model in the NYMEX light sweet crude oil futures market and tests stationarity of the spot-futures differential. It is demonstrated that the primary cause of the "cointegration paradox" is the model misspecifications resulting in omitted variable bias.
Microstructure for Enhanced Plasticity and Toughness
Magnesium is the lightest metal with a very high specific strength. However, its practical applicability is limited by its toughness and reliability. Mg, being HCP has low ductility. This makes the improvement of toughness a grand challenge in Mg alloys. Friction stir processing (FSP) is a thermomechanical technique used to effect microstructural modification. Here, FSP was utilized to affect the toughness of WE43 sheets through microstructural modification. Room temperature Kahn-type tests were conducted to measure the toughness of WE43 sheets. Microscopic techniques (SEM, TEM) was utilized to study the effect of various microstructural factors like grain size, texture, constituent particles, precipitates on crack initiation and propagation. Tensile properties were evaluated by mini-tensile tests. Crack growth in WE43 sheets was also affected by mechanics and digital image correlation (DIC) was utilized to study the plastic zone size. The underlying mechanisms affecting toughness of these sheets were understood which will help in formulating ways in improving it. WE43 nanocomposites were fabricated via FSP. Uniform distribution of reinforcements was obtained in the composites. Improved mechanical properties like that of enhanced strength, increased hardness and stiffness were obtained. But contrary to other metal matrix composites which show reduction in ductility with incorporation of ceramic reinforcements, the nanocomposites showed good strength-ductility combination. The composites were precisely characterized and mechanisms governing this property were studied. The nano-length of the reinforcements was observed to be the main criteria and the dislocation-particle interaction, the main reason behind the strength-ductility property.
Lifecycle Affordability Decisions
SpaceX as aerospace manufacturer and space transport service technology company work along to make reusable rockets, their long term plan is to make spaceflight affordable routine. Elon Musk, as CEO, is involved in every step of decision making as he has mentioned in interviews. The rocket's engine has undergone a number of improvements, and to increase its efficiency and power, a number of parts has been reduced. The redesigning process involves several decisions, such as in-house or out-source production. This research provides a practical framework for contractors, suppliers, and manufacturers to build a more reliable, affordable, and low cost supply chain. As a result, the objective of my dissertation is to explore how managers can extend the useful life of their assets and reduce their total cost of ownership. The main research focus for this dissertation is lifecycle affordability (LCA) for capital intensive products when post production costs are significantly higher than production costs. Lifecycle cost is often not considered by firms in a product, service or asset when making acquisition decisions. Firm's acquisition are mainly based on the initial cost of the product. Decision making without considering the entire lifecycle cost of a product impacts the firm's profitability, revenue, pricing strategies, and competitiveness. Evaluating the trade-offs between all the costs involved in the product lifecycle can help firms to have an estimation of costs before making any acquisition decisions. To address these challenges, lifecycle affordability (LCA) considerations can enable firms to focus their decisions on their long-term investment process rather than trying to save on initial cost of purchasing a product. This dissertation presents the following research question: how has lifecycle affordability been represented in supply chain research to date? And what are constructs of lifecycle affordability? To address this research question, the dissertation is comprised of three separate ...
Effects of UE Speed on MIMO Channel Capacity in LTE
With the introduction of 4G LTE, multiple new technologies were introduced. MIMO is one of the important technologies introduced with fourth generation. The main MIMO modes used in LTE are open loop and closed loop spatial multiplexing modes. This thesis develops an algorithm to calculate the threshold values of UE speed and SNR that is required to implement a switching algorithm which can switch between different MIMO modes for a UE based on the speed and channel conditions (CSI). Specifically, this thesis provides the values of UE speed and SNR at which we can get better results by switching between open loop and closed loop MIMO modes and then be scheduled in sub-channels accordingly. Thus, the results can be used effectively to get better channel capacity with less ISI. The main objectives of this thesis are: to determine the type of MIMO mode suitable for a UE with certain speed, to determine the effects of SNR on selection of MIMO modes, and to design and implement a scheduling algorithm to enhance channel capacity.
Opera and Society in Early-Twentieth-Century Argentina: Felipe Boero's El matrero
Premiering at the twilight of the gauchesco era and the dawn of Argentine musical Modernism, El matrero (1929) by Felipe Boero (1884-1958) remains underexplored in terms of its social milieu and artistic heritage. Instantly hailed as a masterpiece, the work retains a place in the local repertory, though it has never been performed internationally. The opera draws on myths of the gaucho and takes further inspiration from the energized intellectual environment surrounding the one-hundred-year anniversary of Argentine Independence. The most influential writers of the Centenary were Leopoldo Lugones (1874-1938), Ricardo Rojas (1882-1957), and Manuel Gálvez (1882-1962). Their times were marked by contradictions: xenophobia and the desire for foreign approbation; pride in an imaginary, "barbaric" yet noble ideal wiped out by the "civilizing" ambitions of revered nineteenth-century leaders. Krausism, a system of ideas following the teachings of Karl Friedrich Krause (1781-1832), had an impact on the period as exhibited in the political philosophy of Hipólito Yrigoyen (1852-1933), who served as president from 1916 to 1922 and 1928 to 1930 when he was deposed by a right-wing coup d'état. Uncritical applications of traditional understandings of nationalism have had a negative impact on Latin American music scholarship. A distillation of scholarly conceptions of Argentine nacionalismo, which address the meaning of the word as it was used in the early twentieth century, combined with an examination of major works of important literary figures of the Centenary provide a firmer ground for discussion. Gálvez paints a conservative portrait of a refined, well-traveled dilettante who finds true enlightenment only in his own rural, Argentine culture. A liberal, Rojas understands nationalism as devotion to the development of national institutions and local art. Lugones argues the foundation of national art should be the gaucho, and articulates the hierarchical sociabilities it should articulate. Boero adopts elements of Krausism and ...
Data-Driven Decision-Making Framework for Large-Scale Dynamical Systems under Uncertainty
Managing large-scale dynamical systems (e.g., transportation systems, complex information systems, and power networks, etc.) in real-time is very challenging considering their complicated system dynamics, intricate network interactions, large scale, and especially the existence of various uncertainties. To address this issue, intelligent techniques which can quickly design decision-making strategies that are robust to uncertainties are needed. This dissertation aims to conquer these challenges by exploring a data-driven decision-making framework, which leverages big-data techniques and scalable uncertainty evaluation approaches to quickly solve optimal control problems. In particular, following techniques have been developed along this direction: 1) system modeling approaches to simplify the system analysis and design procedures for multiple applications; 2) effective simulation and analytical based approaches to efficiently evaluate system performance and design control strategies under uncertainty; and 3) big-data techniques that allow some computations of control strategies to be completed offline. These techniques and tools for analysis, design and control contribute to a wide range of applications including air traffic flow management, complex information systems, and airborne networks.
An Experimental Study of Bifurcated (Weekend and Weekday) and Unitary (Past Week) Retrospective Assessments of Sleep
Discordance between weekday and weekend sleep schedules is common (Bonnet & Arand, 1995; Breslau, Roth, Rosenthal, & Andreski, 1997; Machado, Varella, & Andrade, 1998; Strauch & Meier, 1988; Tsai & Li, 2004). Brief retrospective self-report measures are essential for epidemiological research studies (Moul, Hall, Pilkonis, & Buysse, 2004), but self-reports are prone to error in recall, and the greater the variability in nightly sleep, the less reliable are retrospective reports (Babkoff, Weller, & Lavidor, 1996). More accurate self-report responses may be possible if measures prompt participants to consider variations in sleep schedules that are consistent (i.e., weekday and weekend sleep schedules). The current study experimentally examined whether Bifurcated (Weekday and Weekend) retrospective assessments of sleep are more accurate than Unitary (Past Week) assessments. Participants were randomly assigned to complete one of the two versions (Bifurcated vs. Unitary) of the Sleep Questionnaire. One hundred and thirty-one participants were included in the analyses. Results of a a series of analyses demonstrated that the Bifurcated version of the Sleep Questionnaire provided more accurate and less variable estimates of total sleep time than the Unitary version of the Sleep Questionnaire. Differences between the versions of the Sleep Questionnaire for other sleep variables were less consistent, and the increased length of the Bifurcated version of the Sleep Questionnaire may have contributed to increased missing and unusable data in this group. Overall, the findings suggest that in both research and clinical work, retrospective measures that examine weekday and weekend sleep separately may offer advantages over retrospective measures that do not differentiate between weekday and weekend sleep.
Scripture for America: Scriptural Interpretation in John Locke's Paraphrase
Is John Locke a philosopher or theologian? When considering Locke's religious thought, scholars seldom point to his Paraphrase and Notes on the Epistles of St. Paul. This is puzzling since the Paraphrase is his most extensive treatment of Christian theology. Since this is the final work of his life, did Locke undergo a deathbed conversion? The scholarship that has considered the Paraphrase often finds Locke contradicting himself on various theological doctrines. In this dissertation, I find that Locke not only remains consistent with his other writings, but provides his subtlest interpretation of Scripture. He is intentionally subtle in order to persuade a Protestant audience to modern liberalism. This is intended to make Protestantism, and specifically Calvinism, the vehicle for modern liberalism. This is seen clearly in Max Weber's The Protestant Ethic and the Spirit of Capitalism. Though Weber concludes that Protestant support for capitalism in the late 19th Century is due to its theological foundation, I find that Weber is actually examining Lockean Protestantism. Locke's success in transforming Protestantism is also useful today in showing how a modern liberal can converse with someone who actively opposes, and may even wish to harm, modern liberalism. The dissertation analyzes four important Protestant doctrines: Faith Alone, Scripture Alone, the church and family, and Christian political life.
Extensions of the General Linear Model into Methods within Partial Least Squares Structural Equation Modeling
The current generation of structural equation modeling (SEM) is loosely split in two divergent groups - covariance-based and variance-based structural equation modeling. The relative newness of variance-based SEM has limited the development of techniques that extend its applicability to non-metric data. This study focuses upon the extension of general linear model techniques within the variance-based platform of partial least squares structural equation modeling (PLS-SEM). This modeling procedure receives it name through the iterative PLS‑SEM algorithm's estimates of the coefficients for the partial ordinary least squares regression models in both the measurement model and the overall structural model. This research addresses the following research questions: (1) What are the appropriate measures for data segmentation within PLS‑SEM? (2) What are the appropriate steps for the analysis of rank-ordered path coefficients within PLS‑SEM? and (3) What is an appropriate model selection index for PLS‑SEM? The limited type of data to which PLS-SEM is applicable suggests an opportunity to extend the method for use with different data and as a result a broader number of applications. This study develops and tests several methodologies that are prevalent in the general linear model (GLM). The proposed data segmentation approaches posited and tested through post hoc analysis of structural model. Monte Carlo simulation allows demonstrating the improvement of the proposed model fit indices in comparison to the established indices found within the SEM literature. These posited PLS methods, that are logical transfers of GLM methods, are tested using examples. These tests enable demonstrating the methods and recommending reporting requirements.
"Counting Out The Harvest"
"Counting Out The Harvest" is a collection of poems exploring intimate encounters. The poems reflect on encounters with memories, family, and the natural and cosmic worlds. In one of the poems, "Red-Throated Anole," the speaker works desperately to save a small dying lizard. In "Ice Storm, Post-Divorce," the speaker attempts to decipher a cluster of ladybugs taking refuge in her room. In the title poem, a couple wonders patiently if their crop will eventually grow. In each of these poems there is a present longing for the construction of a meaningful identity by means of the encounter, but the intersection between speaker and world falls short of satisfaction, whether the faultiness lies in the body's inability to find full sustenance, or in the ever-changing fluidity of memory to find stability. But the poems progress from pressing against this difficulty toward finding a contented resignation to the world's cyclical order. The final line of the manuscript, "disrobe a layer to begin again," indicates an arrival at satisfaction, which is found ultimately in continuation.
Customers' Attitudes toward Mobile Banking Applications in Saudi Arabia
Mobile banking services have changed the design and delivery of financial services and the whole banking sector. Financial service companies employ mobile banking applications as new alternative channels to increase customers' convenience and to reduce costs and maintain profitability. The primary focus of this study was to explore the Saudi bank customers' perceptions about the adoption of mobile banking applications and to test the relationships between the factors that influence mobile banking adoption as independent variables and the action to adopt them as the dependent variable. Saudi customers' perceptions were tested based on the extended versions of IDT, TAM and other diffusion of innovation theories and frameworks to generate a model of constructs that can be used to study the use and the adoption of mobile technology by users. Koenig-Lewis, Palmer, & Moll's (2010) model was used to test its constructs of (1) perceived usefulness, (2) perceived ease of use, (3) perceived compatibility, (4) perceived credibility, (5) perceived trust, (6) perceived risk, and (7) perceived cost, and these were the independent variables in current study. This study revealed a high level of adoption that 82.7% of Saudis had adopted mobile banking applications. Also, the findings of this study identified a statistically significant relationship between all of demographic differences: gender, education level, monthly income, and profession and mobile banking services among adopters and non-adopters. Seven attributes relating to the adoption of mobile banking applications were evaluated in this study to assess which variables affected Saudi banks customers in their adoption of mobile banking services. The findings indicated that the attributes that significantly affected the adoption of mobile banking applications among Saudis were perceived trust, perceived cost, and perceived risk. These three predictors, as a result, explained more than 60% of variance in intention to adopt mobile banking technology in Saudi Arabia. ...
Synthesis and Photochemical Studies of Wide-Band Capturing Sensitizers Capable of Light Energy Harvesting
Artificial photosynthesis, for the purpose of converting solar energy into fuel, is one of the most viable and promising alternative approaches to solve the current global energy and environmental issues. Among the challenges faced in artificial photosynthesis is in building photosystems that can effectively and efficiently perform light absorption and charge separation in broad-band capturing donor-acceptor systems. While having a broad-band capturing antenna system that can harness incoming photons is crucial, another equally important task is to successfully couple the antenna system, while maintaining its optical properties, to an energy or electron acceptor which serves as the reaction center for the generation of charged species of useful potential energy. The stored potential energy will be utilized in different applications such as driving electrons in solar cells or in splitting water for the generation of fuel. Hence, the particular endeavor of this thesis is to study and synthesize molecular/supramolecular systems with wide-band capturing capabilities to generate long-lived charge separated states. The sensitizer used in building these systems in the present study is 4,4-difluoro-4-bora-3a,4a-diaza-s-indacene, for short, BF2 chelated Azaboron dipyrromenthene or AzaBODIPY. A handful of novel donor-acceptor systems based on AzaBODIPY have been successfully designed, synthesized and their photochemistry have been investigated using various techniques. In these systems, Azabodipy has been covalently attached to several donors like porphyrin, bodipy, subphthalocyanine, phenothiazine, ferrocene, bithiophene and effectively coupled to an electron acceptor, C60. These systems have been fully characterized by NMR, Mass, optical absorption and emission, X-ray crystallographic, computational, electrochemical, and photochemical studies. It has been possible to demonstrate occurrence of efficient electron and energy transfer events and long-lived charge separated states upon photoexcitation in these model compounds. By changing the arrangements of the donor and acceptor entities, it has also been possible to show directional, through-space and through-bond electron transfer processes. The present ...
Sensing and Decoding Brain States for Predicting and Enhancing Human Behavior, Health, and Security
The human brain acts as an intelligent sensor by helping in effective signal communication and execution of logical functions and instructions, thus, coordinating all functions of the human body. More importantly, it shows the potential to combine prior knowledge with adaptive learning, thus ensuring constant improvement. These qualities help the brain to interact efficiently with both, the body (brain-body) as well as the environment (brain-environment). This dissertation attempts to apply the brain-body-environment interactions (BBEI) to elevate human existence and enhance our day-to-day experiences. For instance, when one stepped out of the house in the past, one had to carry keys (for unlocking), money (for purchasing), and a phone (for communication). With the advent of smartphones, this scenario changed completely and today, it is often enough to carry just one's smartphone because all the above activities can be performed with a single device. In the future, with advanced research and progress in BBEI interactions, one will be able to perform many activities by dictating it in one's mind without any physical involvement. This dissertation aims to shift the paradigm of existing brain-computer-interfaces from just ‘control' to ‘monitor, control, enhance, and restore' in three main areas - healthcare, transportation safety, and cryptography. In healthcare, measures were developed for understanding brain-body interactions by correlating cerebral autoregulation with brain signals. The variation in estimated blood flow of brain (obtained through EEG) was detected with evoked change in blood pressure, thus, enabling EEG metrics to be used as a first hand screening tool to check impaired cerebral autoregulation. To enhance road safety, distracted drivers' behavior in various multitasking scenarios while driving was identified by significant changes in the time-frequency spectrum of the EEG signals. A distraction metric was calculated to rank the severity of a distraction task that can be used as an intuitive measure ...
"Southern Tongues Leave Us Shining"
A collection of poems that are history- and place-infused lyrical songs that that sounds the landscapes and distances of the South, with a critical preface that explores erotic encounters with the divine.
The Spinning Place
"The Spinning Place" finds its impetus in the intersection of the spiritual and material, and while often dwelling in a domestic milieu, the poems move outward both figuratively and literally. For instance, one poem re-narrates the tale of Rumpelstiltskin, several poems are about divination by various means (frogs, animal behavior), and another performs an erasure of the last supper so that it instead tells a woman's experience in a delivery room. I borrow the title of the collection from a stanza of Dylan Thomas's poem "Fern Hill," and the excerpt (which will become an epigraph to the book) reads: "So it must have been after the birth of the simple light / In the first, spinning place, the spellbound horses walking warm / Out of the whinnying green stable / On to the fields of praise." Thomas refers to the newly created earth as the "spinning place," imagining the fleeting idyll and harmony of that scene. In a similar way, my new poems specifically explore moments of creation, birth, and discovery, drawing from a variety of inspirations, including recognizable narratives and myths, as well as personal experience.
Using Pre-Session Mindfulness to Improve Session Presence and Effectiveness: A Randomized-Controlled Trial
While a significant amount of research illustrates the overall positive effects of therapists' general use of mindfulness, very few studies have addressed whether therapists' use of mindfulness translates to improved psychotherapy outcomes. The present study utilized a randomized-controlled design to test whether a brief mindfulness training program and pre-session mindfulness practice could have a positive impact on therapy; in particular, we hypothesized that mindfulness training and practice would improve ratings on therapeutic presence as rated by clients and therapists and session effectiveness as rated by clients. The present study also examined whether clients' subjective ratings of therapy outcome and therapists' theoretical orientation impacted outcome measures after therapists completed mindfulness training. The 20 participating therapists were randomly assigned to either the mindfulness training (MT) group or control group according to a computer generated randomization list. Results indicated that clients did not significantly improve on outcome measures after completing the mindfulness training. Clients' subjective ratings on a psychotherapy outcome measure did predict changes in their ratings of therapeutic presence. This finding may have important implications for future research examining client characteristics that may moderate the relationship between therapeutic presence and session outcomes. Limitations of the present study and future directions are discussed.
Using Topic Models to Study Journalist-Audience Convergence and Divergence: The Case of Human Trafficking Coverage on British Online Newspapers
Despite the accessibility of online news and availability of sophisticated methods for analyzing news content, no previous study has focused on the simultaneous examination of news coverage on human trafficking and audiences' interpretations of this coverage. In my research, I have examined both journalists' and commenters' topic choices in coverage and discussion of human trafficking from the online platforms of three British newspapers covering the period 2009–2015. I used latent semantic analysis (LSA) to identify emergent topics in my corpus of newspaper articles and readers' comments, and I then quantitatively investigated topic preferences to identify convergence and divergence on the topics discussed by journalists and their readers. I addressed my research questions in two distinctive studies. The first case study implemented topic modelling techniques and further quantitative analyses on article and comment paragraphs from The Guardian. The second extensive study included article and comment paragraphs from the online platforms of three British newspapers: The Guardian, The Times and the Daily Mail. The findings indicate that the theories of "agenda setting" and of "active audience" are not mutually exclusive, and the scope of explanation of each depends partly on the specific topic or subtopic that is analyzed. Taking into account further theoretical concepts related to agenda setting, four more additional research questions were addressed. Topic convergence and divergence was further identified when taking into account the newspapers' political orientation and the articles' and comments' year of publication.
Synthesis, Characterization and Catalytic Studies of Chiral Gold Acyclic Diaminocarbene Complexes
Chiral gold complexes have been applied in homogeneous catalytic reactions since 1986, in some cases with high enantioselectivity. Acyclic diaminocarbene (ADC) ligands are acyclic analogues of N-heterocyclic carbenes (NHCs) that have larger N-CCarbene-N angles and stronger donating ability. ADCs have been developed as alternatives to phosphine and NHC ligands in homogeneous gold catalysis. In 2012, a new series of chiral gold(I) ADCs were first developed by Slaughter's group and were shown to give remarkable enantioselectivities in some reactions. Because of the hindered rotation of the N-CCarbene bonds of ADC, chiral ADC substituents can easily get close to the metal center in some conformations, although two rotameric structures are formed if the chiral amine is nonsymmetric. The selective of specific ADC conformations was the initial focus of this study. Formational selectivity of one diastereomer of an ADC ligand during synthesis was examines by measuring the relative rates of diastereomer formation in a 1H NMR kinetic study. The potential for converting multiple conformational isomers of ADCs into a single conformation, or at least a simpler mixture, was examined. This study used the analogy that anti- isomer has electronic and structural similarity with urea/thiourea, raising the possibility that 1,8-naphthyridine can be used to favor certain conformations through a self-assembled hydrogen-bonding complex. Gold(I) is a soft carbophilic Lewis acid able to active C-C π bonds to nucleophilic attack, and ADC-gold complexes are potentially useful in this regard. Therefore, biaryl gold(I) ADC complexes were examine with silver salt additives in catalytic 1,6-enyne cyclization reaction. A detailed study found that the counteranion affects the regioselectivities of these reactions more than substituents on the ancillary ADC ligands.
Reading the Ruptured Word: Detecting Trauma in Gothic Fiction from 1764-1853
Using trauma theory, I analyze the disjointed narrative structure of gothic works from 1764-1853 as symptomatic of the traumatic experience. Gothic novels contain multiple structural anomalies, including gaps in experience that indicate psychological wounding, use of the supernatural to violate rational thought, and the inability of witnesses to testify to the traumatic event. These structural abnormalities are the result of trauma that characters within these texts then seek to prevent or repair via detection.
Workfunction tuning of AZO Films Through Surface Modification for Anode Application in OLEDs.
Widespread use of organic light emitting diodes (OLEDs) in solid state lighting and display technologies require efficiency and lifetime improvements, as well as cost reductions, inclusive of the transparent conducting oxide (TCO). Indium tin oxide (ITO) is the standard TCO anode in OLEDs, but indium is expensive and the Earth's reserve of this element is limited. Zinc oxide (ZnO) and its variants such as aluminum-doped ZnO (AZO) exhibit comparable electrical conductivity and transmissivity to ITO, and are of interest for TCO applications. However, the workfunction of ZnO and AZO is smaller compared to ITO. The smaller workfunction of AZO results in a higher hole injection barrier at the anode/organic interface, and methods of tuning its workfunction are required. This dissertation tested the hypothesis that workfunction tuning of AZO films could be achieved by surface modification with electronegative oxygen and fluorine plasmas, or, via use of nanoscale transition metal oxide layers (MoOx, VOx and WOx). Extensive UPS, XPS and optical spectroscopy studies indicate that O2 and CFx plasma treatment results in an electronegative surface, surface charge redistribution, and a surface dipole moment which reinforces the original surface dipole leading to workfunction increases. Donor-like gap states associated with partially occupied d-bands due to non-stoichiometry determine the effective increased workfunction of the AZO/transition-metal oxide stacks. Reduced hole injection barriers were engineered by ensuring that the surface ad-layers were sufficiently thin to facilitate Fowler-Nordheim tunneling. Improved band alignments resulted in improved hole injection from the surface modified AZO anodes, as demonstrated by I-V characterization of hole only structures. Energy band alignments are proposed based on the aforementioned spectroscopies. Simple bilayer OLEDs employing the surface modified AZO anodes were fabricated and characterized to compare their performance with standard ITO. Anodes consisting of AZO with MoOx or VOx interfacial layers exhibited 50% and 71% improvement in ...