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Allusions and Borrowings in Selected Works by Christopher Rouse: Interpreting Manner, Meaning, and Motive through a Narratological Lens
Christopher Rouse (b. 1949), winner of the Pulitzer Prize for his Trombone Concerto (1993) and a Grammy award for his Concerto de Gaudi (1999), has come to the forefront as one of America's most prominent orchestral composers. Several of Rouse's works feature quotations of and strong allusions to other composers' works that are used both rhetorically and structurally. These borrowings range from a variety of different genres and styles of works, from Claudio Monteverdi's L'incoronazione di Poppea to Jay Ferguson's "Thunder Island." Due to the more accessible filtering and funneling methods of musical borrowings (proliferation of mass media), the weighty discourses attached to them, and their variety of functions (critiquing canons, engaging in an allusive tradition, etc.), quotation has become elevated to the most prominent of musical actors that trigger narrative listening strategies, which in turn have a stronger role in the formation of narratives about music as well as narratives of music. The primary aim of this study is to adapt and apply more recent methodological narrativity frameworks to selected instrumental compositions by Rouse containing quotations, suggesting that their manner of insertion, their method of disclosure, and their referential potential can benefit from being examined through various narrative lenses as well as reveal their participation in certain roles of narrative functions. For this study, I have chosen six instrumental works by Rouse for examination - the Violoncello Concerto, Symphony No. 1, Iscariot, String Quartet No. 2, Seeing, and Thunderstuck. On a more specific level, the aim of this study is to investigate the manner, meaning, and motive of the quoted material in a select group of Rouse's compositions through various narratological lenses. To accomplish this, I intend 1) to establish a context for understanding the musical borrowing procedures of Rouse; 2) to explore how works containing quotations can be …
Application-Focused Investigation of Monovalent Metal Complexes for Nanoparticle Synthesis
Over the last 20 years, there has occurred an increase in the number, scope, and impact of nanomaterials projects. By leveraging the Surface Plasmon Resonance of metallic nanoparticles for labelling, sensing, and treatment, researchers have demonstrated the versatile utility of these nanomaterials in medicine. The literature provides evidence of use of simple, well-known chemistry for nanomaterials synthesis when the focus is new applications of nanomaterials. A case in point, is the synthesis of metallic nanoparticles, whereby HAuCl4, CuCl2, Cu(acac)2, and AgNO3 are typically employed as nanoparticle precursors. Unfortunately, the use of these precursors limits the number of applications available to these materials - particularly for AuNPs in medicine, where the byproducts of nanoparticle synthesis (most often surface-adsorbed reductants, toxic stabilizers, and growth directors) cause nanoparticles to fail clinical trials. Despite the several thousand publications detailing the advancements in nanoparticle therapeutics, as of 2017, there were only 50 FDA-approved nanoparticle formulations. Less than 10 were based on metallic nanoparticles. This is a problem because many of these nanoparticle therapeutics demonstrate potent cell killing ability and labeling of cells. A solution to this problem may be the use of weakly coordinated, monovalent metal complexes, which require only one electron to reduce them to their metallic state. Further, by designing nanoparticle syntheses around these monovalent complexes, we can employ weaker, environmentally friendly stabilizers. This strategy also forgoes the use of exogenous reducing agents, because the monovalent complexes can be reduced and stabilized by one reagent. Herein we investigate the use of Au(Me2S)Cl, [Cu(MeCN)4]BF4, and AgBF4 with green stabilizers to synthesize a variety of nanomaterials. We find that a range of sizes of spherical particles, as well as a range of sizes of gold triangular prisms can be synthesized by using techniques that follow this strategy.
Asian and Asian Indian American Immigrant Students: Factors Influencing Their Academic Performance
Asian American students have done well in school; they have had higher academic achievements, higher academic scores, lower dropout rates and higher college entrance rates as compared to other minorities and generally other students in the United States (U.S.). A possible explanation to the higher academic performance and achievement of the Asian American students is that they are more likely to have experienced an environment that is conducive to learning at home; their parents were involved and held higher expectations. Immigrant minorities have been found to do well in schools in many parts of the world. Similarly, here in the U.S. there has been increasing evidence that students of Asian ancestry, both immigrants and U.S. born, complete more years of education than most of the other ethnicities. Current research and data on the academic performance of Asian immigrants includes most Asian countries. This study reviewed the current literature regarding the factors that influence the academic performance of "Asian Indian Americans" who attended high schools in the U. S. This correlational study examined the relationship between various factors, such as parental participation, parental expectations and involvement, discipline, cultural beliefs, personal identity and values, language spoken at home, and the academic performance of the Asian Indian Americans.
Beyond Nothingness: A Broader Nihilism in Cinema Paradiso by Stephen Goss
Stephen Goss composed Cinema Paradiso, a six-movement suite for solo guitar, as an homage to films and film directors. Goss cites nihilism as a theme in Dogville, the film that inspires the fourth movement, "Mandalay," but I assert that all the films and many musical devices throughout the piece can be read through the lens of nihilism. The first movement, "Paris, Texas," depicts the stark landscape of the opening scene of the 1984 Wim Wenders film of the same name. "Modern Times" chronicles Charlie Chaplin's slapstick-laden descent from the factory to the insane asylum in the opening sequence of his 1936 Modern Times. "Noir" is a tribute to the procedures of film noir: violent storylines that depict the harshness of life, dim lighting, and anti-hero characters, all accompanied by jazz. Lars von Trier's Dogville provides the movement "Mandalay" with its nihilistic meaning, but Goss writes that he invokes the musical style of Kurt Weill's opera The Rise and Fall of the City of Mahagonny. Just as the book people of François Truffaut's Fahrenheit 451 had to pass on books orally, Goss has burned the score for his "451," forcing guitarists to learn it by watching a video and listening to a recording. Finally, the chaotic tarantella, "Tarantino" depicts Uma Thurman's heroin overdose scene in Quinten Tarantino's Pulp Fiction. By analyzing Fredrich Nietzsche's writings to form a broader definition of nihilism and applying that definition first to each film and then to corresponding musical elements in each movement, this paper argues that nihilism acts as a connecting theme throughout Cinema Paradiso.
Bio-Inspired Material Surfaces with Self-cleaning, Micromanipulation and Water Collection
Geckos are famous for the skill of switchable adhesion that they use to stick on various surface while keep their fingers super clean. In the dissertation, a unique mechanism was discovered to explain gecko self-cleaning phenomena. Using atomic force microscopy (AFM), we managed to compare the microparticle-substrate adhesion and the microparticle-seta adhesion with a single seta bonded to the AFM cantilever. A dynamic effect was approved that high pulling-off speed could increase the microparticle-substrate adhesion and thus the self-cleaning appears at high moving speed. Based on the self-cleaning theory, a gecko-inspired N-doped graphene surface with switchable adhesion was achieved, which was designed into a bio-inspired micromanipulator with a success rate over 90%. When electrical bias was applied on this biomimetic surface, the charge concentration induced an electrical double layer (ELD) on the convex surfaces, which attracts polar water molecules to form a water bridge on it, significantly enhancing the adhesion on the wrinkled graphene surface, mimicking the capillary force on beetle feet. Therefore, the bio-inspired adhesive surface can be controlled with speed, electrical bias, humidity and different material surfaces. The water attraction phenomenon on the polarized surface was further tested for the potential application of water collection and evaporation in microsystems.
Bipolar Spectrum Traits in Day-to-Day Life: Ecological Momentary Assessment of Reward Sensitivity, Circadian Timing, and Experience of Reward in the Environment
The current study examined 236 undergraduate students in a week long twice-per-day ecological momentary assessment exploring the influence of baseline reward sensitivity and interactions between circadian variables (i.e., total sleep time, sleep quality) and daily measures of reward. Though primary study findings did not support reward sensitivity related moderation of sleep-reward pathways, a number of notable findings emerged. We found evidence of specific domains of reward sensitivity (anticipatory reward and reward responsiveness) which are uniquely related to daily experiences of reward. In addition, bidirectional circadian-reward pathways were found between sleep quality and daily rewards which suggests pathways towards reward-related engagement. Evidence also supported interactions between sleep quality and total sleep time on experience of daily reward, further highlighting the complexity of sleep-reward pathways and their relevance to mood symptoms.
Brazos
Brazos is a collection of poetry that comments on and critiques life in a small town in Texas. These poems situate the speaker both in this town and in spaces removed from the town, but the work always grapples with questions of how the speaker identifies himself via the relationship to that space. The creative portion is accompanied by a critical introduction that looks at the intersections of poetry and the lyric essay.
Carbon Nanotubes and Molybdenum Disulfide Protected Electrodes for High Performance Lithium-Sulfur Battery Applications
Lithium-sulfur (Li-S) batteries are faced with practical drawbacks of poor cycle life and low charge efficiency which hinder their advancements. Those drawbacks are primarily caused by the intrinsic issues of the cathodes (sulfur) and the anodes (Li metal). In attempt to resolve the issues found on the cathodes, this work discusses the method to prepare a binder-free three-dimensional carbon nanotubes-sulfur (3D CNTs-S) composite cathode by a facile and a scalable approach. Here, the 3D structure of CNTs serves as a conducting network to accommodate high loading amounts of active sulfur material. The efficient electron pathway and the short Li ions (Li+) diffusion length provided by the 3D CNTs offset the insulating properties of sulfur. As a result, high areal and specific capacities of 8.8 mAh cm−2 and 1068 mAh g−1, respectively, with the sulfur loading of 8.33 mg cm−2 are demonstrated; furthermore, the cells operated at a current density of 1.4 mA cm−2 (0.1 C) for up to 150 cycles. To address the issues existing on the anode part of Li-S batteries, this work also covers the novel approach to protect a Li metal anode with a thin layer of two-dimensional molybdenum disulfide (MoS2). With the protective layer of MoS2 preventing the growth of Li dendrites, stable Li electrodeposition is realized at the current density of 10 mA cm−2; also, the MoS2 protected anode demonstrates over 300% longer cycle life than the unprotected counterpart. Moreover, the MoS2 layer prevents polysulfides from corroding the anode while facilitating a reversible utilization of active materials without decomposing the electrolyte. Therefore, the MoS2 protected anode enables a stable cycle life of over 500 cycles at 0.5 C with the high sulfur loading amount of ~7 mg cm−2 (~67 wt% S content in cathode) under the low electrolyte/sulfur (E/S) ratio of 6 μL mg−1. This …
Ceramide Biosynthesis and NEET Proteins Impact Development, Function, and Maintenance of the Caenorhabditis elegans Germline
I used the C. elegans genetic model to examine the role of ceramide biosynthesis (sphingolipid pathway) and iron regulation and found that each process impacts germline development and function. Using a sphingolipid specific antibody mAb15B4, I found that sphingolipids are associated with germ granules (P granules) within C. elegans and zebrafish; thus, suggesting conservation of macromolecules associated with germ granules. Phenotype analysis of ceramide biosynthesis mutants in C. elegans revealed that this pathway is essential for normal germline function in the aging adult hermaphrodite; specifically, precocious germline senescence was observed. Furthermore, I found that disruption of ceramide biosynthesis, via the hyl-2 deletion mutation, negatively impacts mAb15B4 localization at the P granules. Through genetic suppression analysis, I determined that insulin signaling and lipid biosynthesis can modulate the mAb15B4 localization to P granules. Additional, phenotype analysis showed that ceramide biosynthesis dysfunction decreased fecundity, and led to germline structure defects and uterine tumors. Through suppression analysis, I determined that modulation of the insulin signaling pathway suppressed the precocious germline senescence due to ceramide biosynthesis dysfunction. Since the presence of uterine tumors is associated with reproductive senescence I concluded that ceramide biosynthesis has a role in germline maintenance in the aging of the germline (germline senescence). The other important fate of a germ cell is programmed cell death. Apoptosis, which occurs through a highly conserved molecular pathway, is a normal component of growth and homeostatic processes. I used C. elegans to gain a greater understanding of the cisd gene function. The C. elegans genome has three previously uncharacterized cisd genes which code for CISD-1 (homology to vertebrate mitoNEET/CISD1 and NAF-1/CISD2) and CISD-3.1 and CISD-3.2 (homology to vertebrate Miner2/CISD3). I determined that independent disruption of the cisd genes resulted in a significant increase in the number of cell corpses within the adult hermaphrodite germline. Genetic …
Cesarean Section Delivery and Exclusive Breastfeeding in Pakistan: Emerging Challenges
This research examined two interrelated issues relevant to maternal and neonatal health in Pakistan, namely, the rising rates of C-section delivery and low rates of exclusive breastfeeding. By using the Andersen's health behavioral model to frame two empirical studies, the data from the Pakistan Demographic and Health Survey (PDHS) 2012-13 was used. The first empirical study examined the correlation between place of delivery and the odds of cesarean section in Pakistan. Not all Pakistani women have an equal chance of delivering at a health facility where C-section delivery takes place; therefore, the study modeled mode of delivery as a two-step process. In the first step, place of delivery was a function of medical indications and various sociodemographic and community factors. Women who delivered at a health facility were included in the second step, where C-section was a function of medical indications and type of facility (private, public). It is found that women who delivered at a private health facility were more likely to have a C-section, even after controlling for the effects of medical/clinical factors, which is concerning. Findings suggest that the private maternal health sector in Pakistan may be over-medicalizing childbirth. The second study examined this paradox of low exclusive breastfeeding in Pakistan, taking into account not only individual-level characteristics of the child and parents, but also place and mode of delivery, sociocultural factors, and community composition. The sample consisted of 1,044 children 0-5 months old, currently living with their mothers. Binary logistic regressions of exclusive and predominant breastfeeding found women who delivered vaginally, whether at home or health care facility were more likely than mothers who delivered via C-section to predominantly breastfeed their infant, and that mothers who delivered vaginally at a health care facility were more likely than their peers who delivered via C-section to exclusively breastfeed …
Characterization, Analysis, and Optimization of Rotary Displacer Stirling Engines
This work focuses on an innovative Rotary Displacer SE (RDSE) configuration for Stirling engines (SEs). RDSE features rotary displacers instead of reciprocating displacers (found in conventional SE configurations), as well as combined compression and expansion spaces. Guided by the research question "can RDSE as a novel configuration achieve a higher efficiency compared to conventional SE configurations at comparable operating conditions?", the goal of this study is to characterize, analyze, and optimize RDSE which is pursued in three technical stages. It is observed the RDSE prototype has an optimum phase angle of > 90° and thermal efficiency of 15.5% corresponding to 75.2% of the ideal (Carnot) efficiency at the source and sink temperatures of 98.6° C and 22.1° C, respectively. Initial results indicate that 125° phase angle provides more power than that of the theoretically optimum 90° phase angle. The results also show comparable B_n and significantly higher W_n values (0.047 and 0.465, respectively) compared to earlier studies, and suggest the RDSE could potentially be a competitive alternative to other SE configurations. Furthermore, due to lack of a regenerator, the non-ideal effects calculated in the analytical approach have insignificant impact (less than 0.03 kPa in 100 kPa). The clearance volume in the shuttled volume has a dramatic negative effect and reduces the performance up to 40%. Ultimately, utilizing CFD, it is proved that the existing geometry is relatively optimized where the optimum phase angle is 121° and geometric ratio D\/L for the displacer is 0.49.
Choice Androgyny
This work provides an alternative theory of gendered consumption that explains chronic and situational shifts in consumers' preferences for masculine, feminine, and androgynous choices, beyond the effects of gender identities.
Complex-Restricted Repetitive Patterns of Vocal Behavior of Individuals with High Functioning Autism: An Innovative Intervention
Repetitive verbal patterns of speech are a trait associated with high-functioning autism (HFA). For some, this higher-order restricted, repetitive behavior impedes learning, social opportunities, and access to work environments. Despite emerging motivation for establishing social relationships, some individuals with HFA lack the behavioral prerequisites to establish meaningful relationships. The purpose of this study is to demonstrate the effectiveness of teaching interaction to decrease higher-order verbal restricted and repetitive behaviors (RRBs) for four adults with HFA. Through a multiple baseline design across participants, individuals were exposed to a function-based intervention (i.e., teaching interaction) that systematically taught and reinforced alternative communicative behaviors while interrupting repetitive speech with specific feedback. Teaching interaction effectively reduced RRBs and increased alternative conversation for all four participants. Three of the four participants elected to participate in post-intervention maintenance sessions that occurred in individualized naturalistic settings. Their conversation behaviors maintained with one participant receiving one booster session.
Computational Development of Trimetallic Cyclotrimers for Gas-Filtration Applications through Non-Covalent Interactions
Photophysical properties of an array of various polyaromatic hydrocarbons were benchmarked with B3LYP, M06 and B97D methods coupled with Pople and CEP-31G(d) basis sets. Results from the benchmark show the importance of diffuse basis sets when modeling the electronic properties of highly conjugated systems and provide qualitative reliable accuracy with certain levels of theory. B97D and M06 are applied to modeling pyrene adducts governed by non-covalent interactions in both gaseous and condensed states to reproduce experimental spectra. DFT calculations with both B97D and M06 functionals show qualitatively and quantitatively that pyrene dimer is a stronger π–base as compared to its monomer. Binding energies coupled with MEP, PCA and Qzz results show that the difference in π-basicity of the monomer and dimer impacts the supramolecular chemistry involved in adducts formed with super π-acidic silver cyclometallic trimer (CTC). Non-covalent interactions between coinage metal CTCs and ammonia/phosphine substrates is reported. Interactions between these substrates and the facial plane of the π-rich gold CTC reveal a novel interaction, where the typical Lewis acid/base roles are reversed for the substrates. Adducts formed through this type of interaction define typical Lewis bases like ammonia and phosphine as Lewis acids, wherein the partially positive hydrogens coordinate to the metallo-aromatic center through dipole-quadrupole interactions. Interactions of ammonia at the side positions is shown to heavily impact the Lewis basicity of the CTC facial plane leading to similar interactions exhibited by the ammonia-gold CTC adducts. Structural and electronic properties of the adducts modeled are examined.
Computational Studies of C-H Bond Activation and Ethylene Polymerization Using Transition Metal Complexes
This work discusses the C-H bond activation by transition metal complexes using various computational methods. First, we performed a DFT study of oxidative addition of methane to Ta(OC2H4)3A (where A may act as an ancillary ligand) to understand how A may affect the propensity of the complex to undergo oxidative addition. Among the A groups studied, they can be a Lewis acid (B or Al), a saturated, electron-precise moiety (CH or SiH), a σ-donor (N), or a σ-donor/π-acid (P). By varying A, we seek to understand how changing the electronic properties of A can affect the kinetics and thermodynamics of methane C–H activation by these complexes. For all A, the TS with H trans to A is favored kinetically over TS with CH3 trans to A. Upon moving from electron-deficient to electron-rich moieties (P and N), the computed C–H activation barrier for the kinetic product decreases significantly. Thus, changing A greatly influences the barrier for methane C–H oxidative addition by these complexes. Secondly, a computational study of oxidative addition (OA) of methane to M(OC2H4)3A (M = Ta, Re and A = ancillary ligand) was carried out using various computational methods. The purpose of this study was to understand how variation in A and M affects the kinetics and thermodynamics of OA. Results obtained from MP2 calculations revealed that for OA of CH4 to Re(OC2H4)3A, the order of ΔG‡ for a choice of ancillary ligand is B > Al > SiH > CH > N > P. Single point calculations for ΔG‡ obtained with CCSD(T) showed excellent agreement with those computed with MP2 methods. MCSCF calculations indicated that oxidative addition transition states are well described by a single electronic configuration, giving further confidence in the MP2 approach used for geometry optimization and ΔG‡ determination, and that the transition states are more …
Computational Studies of Catalysis Mediated by Transition Metal Complexes
Computational methods were employed to investigate catalytic processes. First, DFT calculations predicted the important geometry metrics of a copper–nitrene complex. MCSCF calculations supported the open-shell singlet state as the ground state of a monomeric copper nitrene, which was consistent with the diamagnetic character deduced from experimental observations. The calculations predicted an elusive terminal copper nitrene intermediate. Second, DFT methods were carried out to investigate the mechanism of C–F bond activation by a low-coordinate cobalt(I) complex. The computational models suggested that oxidative addition, which is very rare for 3d metals, was preferred. A π–adduct of PhF was predicted to be a plausible intermediate via calculations. Third, DFT calculations were performed to study ancillary ligand effects on C(sp3)–N bond forming reductive elimination from alkylpalladium(II) amido complexes with different phosphine supporting ligands. The dimerization study of alkylpalladium(II) amido complexes indicated an unique arrangement of dative and covalent Pd-N bonds within the core four-membered ring of bimetallic complexes. In conclusion, computational methods enrich the arsenal of methods available to study catalytic processes in conjunction with experiments.
Decision Making in Alternative Modes of Transportation: Two Essays on Ridesharing and Self-Driving Vehicles
This manuscript includes an investigation of decision making in alternative modes of transportation in order to understand consumers' decision in different contexts. In essay 1 of this study, the motives for participation in situated ridesharing is investigated. The study proposes a theoretical model that includes economic benefits, time benefits, transportation anxiety, trust, and reciprocity either as direct antecedents of ridesharing participation intention, or mediated through attitude towards ridesharing. Essay 2 of this study, focuses on self-driving vehicles as one of the recent innovations in transportation industry. Using a survey approach, the study develops a conceptual model of consumers' anticipated motives. Both essays use partial least square- structural equation modeling for assessing the proposed theoretical models.
Deep Learning Approach for Sensing Cognitive Radio Channel Status
Cognitive Radio (CR) technology creates the opportunity for unlicensed users to make use of the spectral band provided it does not interfere with any licensed user. It is a prominent tool with spectrum sensing functionality to identify idle channels and let the unlicensed users avail them. Thus, the CR technology provides the consumers access to a very large spectrum, quality spectral utilization, and energy efficiency due to spectral load balancing. However, the full potential of the CR technology can be realized only with CRs equipped with accurate mechanisms to predict/sense the spectral holes and vacant spectral bands without any prior knowledge about the characteristics of traffic in a real-time environment. Multi-layered perception (MLP), the popular neural network trained with the back-propagation (BP) learning algorithm, is a keen tool for classification of the spectral bands into "busy" or "idle" states without any a priori knowledge about the user system features. In this dissertation, we proposed the use of an evolutionary algorithm, Bacterial Foraging Optimization Algorithm (BFOA), for the training of the MLP NN. We have compared the performance of the proposed system with the traditional algorithm and with the Hybrid GA-PSO method. With the results of a simulation experiment that this new learning algorithm for prediction of channel states outperforms the traditional BP algorithm and Hybrid GA-PSO method with respect to classification accuracy, probability of misdetection, and Probability of false alarm.
Defining Components Linked to Bacterial Nutritional Utilization of Cyanide as a Sole Nitrogen Source
One of the challenges in biology is placing a function on the myriad of gene sequences having become available from rapid advances in genome sequencing. One such example is a gene cluster (Nit1C) found in bacteria that is tied to the unusual ability of certain bacteria to grow when supplied cyanide as the sole nitrogen source. The term cyanotrophs has been applied to such bacteria, for which a genetic linkage between cyanotrophy and Nit1C was demonstrated for 10 separate bacteria. In addition to growth, cyanide induced the expression of Nit1C genes in all organisms tested, and in one case, deletion of one of the Nit1C genes (nitC) caused a loss of growth. Of the ten bacteria able to grow cyanotrophically, all gave evidence of harboring Nit1C on their genome except for two (Pseudomonas fluorescens Pf11764 and P. monteilii BCN3), which were sequenced and the presence of Nit1C was also confirmed. A broader search of bacteria identified 270 separate strains with the cluster, all limited to bacteria spanning the phyla Firmicutes, Actinobacteria, Proteobacteria and Cyanobacteria. Remarkably, many examples of a single representative of a given taxon contained Nit1C, most poignantly displayed by Pf11764 and PmBCN3; the interpretation being the cluster was likely acquired by horizontal gene transfer in response to cyanide as an environmental cue. Consistent with its absence in Archaea is the time line for the emergence of cyanide producing organisms (cyanogens) on earth dating back only 400-500 million years.
Design, Synthesis and Characterization of Polymer and Protein Coated Hybrid Nanomaterials: Investigation of Prototypes for Antimicrobial and Anticancer Applications
This work involves synthesis and characterization of isotropic and anisotropic noble metal nanoparticles for applications ranging from antimicrobial uses to anticancer applications. These nanomaterials are stabilized in genuinely benign biomaterials ranging from polymers to cross linked proteins for targeted cancer treatments. The nanoparticles are found to have tunable optical properties.
Development and Testing of Gold(I) and Europium(III) Based Sensors for Environmental Applications
This dissertation focuses on the development, characterization, and analysis of luminescent materials and coatings for sensing applications, including CO2, heavy metals, and silver. Chapter 2 involves the use of a gold(I) pyrazolate trimer that is able to detect silver ions with an AgNP medium. Detection of silver is vital, because there is an influx of silver into our environment caused by the increased use of AgNP. Therefore, having a sensor that is able to differentiate between and detect only Ag ions is an important first step to solving the toxicity mystery of AgNPs. Chapter 3 focuses on the development of sensor coatings containing a Eu(III) based luminescent system for sensing dissolved CO2 without the aid of an absorption-based dye. It is well-known that monitoring CO2 levels in our environment is important since even at low concentrations it can cause adverse health effects to the human body. This work demonstrates a pH-sensitive Eu complex being used directly as a CO2 sensor without the aid of any other absorption-based dye. Chapter 4 explores the idea of developing a heavy metal sensor for lead and its ability to detect lead in wide concentration range upon changing the pH of the medium and the polymer matrix. Different heavy metals have toxicity at different concentrations, therefore, being able to change the dynamic range of the sensor is advantageous. This research is the first step towards developing a luminescent Pb sensor with a tunable dynamic range.
Disasters, Smart Growth and Economic Resilience: An Empirical Analysis of Florida Cities
This dissertation examines the relationship between economic resilience, disaster experience, and smart growth policies at the local government level. The study is based upon three research questions that examine spatial distribution of economic resilience in Florida cities, and examines the impact of disaster experience, and smart growth policies adopted by local governments on economic resilience. Based upon the bounce-forward approach (Cowell, 2013; Klein et al. 2003), economic resilience is defined using three dimensions—economic stability, economic equity, and economic diversity. The spatial analysis is conducted by mapping economic resilience scores across 780 Census Designated Places in Florida through standard deviation method of classification, and conducting cluster-outlier analysis. Results suggest difference in economic resilience within coastal and inland communities—with higher scores mostly situated inland. East Central Florida, Tampa Bay, and South Florida were identified as high economic resilience clusters, and Northwest Florida was identified as low resilience cluster. Impact of disaster experience, and smart growth policies on economic resilience was examined based upon logic of focusing events by Birkland (1997, 2010). Data was collected from the U.S. Census, the National Climatic Data Center, and the Energy Sustainable Florida Communities Survey conducted by Florida State University in 2009. Results suggest significant association between disaster experience of communities and their level of economic resilience, highlighting the importance of community learning in building capacity for resilience after disasters. The results also highlight the need of balancing mitigation and adaptation strategies. Mixed-use development policies, green building certification, and energy savings policies were found to have a significant positive impact on economic resilience.
Diverse Learners in the Classroom: Students with Special Needs Enrolled in Science, Technology, Engineering, and Mathematics (STEM) Texas Public Classrooms
The purpose of this study was to determine if students with special needs participating in an inclusive classroom can learn the skills related to a STEM career as compared to the general student population. The study involved seventh grade students from two rural middle schools in north central Texas and was framed through a constructivist lens using a quasi-experimental design with a convenience sample. The Solenoid Invention Kit Assessment and the STEM Semantics Survey used in this study were used from a previously large existing dataset from a grant funded by the National Science Foundation for Innovative Technology Experiences for Students and Teachers. Findings suggested that there were no significant differences between the general student population and students with special needs. However, STEM coursework in an inclusive classroom may impact students' decision to pursue STEM careers.
Effects of Telepractice for Training Autism Teachers to Contrive Motivating Operations
The rising rate of the autism spectrum disorders (ASD) has resulted in challenges for teachers in public schools, concerning the delivery of evidence-based practices for superior outcomes. Thus, school districts are in need of professional learning options that can be efficiently and effectively delivered to improve the procedural fidelity of interventions. The purpose of this study is to demonstrate the effectiveness of using telepractice to teach autism teachers how to contrive motivating operations to teach manding to students with ASD. By utilizing multiple baselines across participants design, four autism teachers in public schools received intervention support through an online module along with video models as well as direct performance feedback from autism specialists via video-conferencing. The primary dependent variable was the percentage of correct responses from the instructional procedures of task analysis, and the secondary measure was the subsequent rate of student mands. Data were analyzed both visually (i.e., through the study of behavioral patterns) and statistically (i.e., analysis of effect size). Results indicate that telepractice increased accuracy of both teacher and student target responses.
The Effects of the IAM Workshop on Preservice Teachers' Perceptions and Attitudes on Integrating Art and Mathematics In Saudi Arabia
This mixed-methods dissertation used an explanatory sequential design to examine art and mathematics preservice teachers' perceptions and attitudes towards integrating art and mathematics (IAM) after an IAM workshop. The conceptual framework of this study has its basis in three theoretical sources: constructivism, multiple intelligence theory, and semiotics. Each of these sources provides a conceptual lens to examine art integration in the curriculum and the teacher's role in facilitating this instructional process. Participants of this study included two sub-groups at a large university in Saudi Arabia. The first sub-group was preservice teachers of art education. The second sub-group was preservice teachers of mathematics. Quantitative and qualitative results indicated that the IAM workshop had positive impacts on art and mathematics preservice teachers' attitudes and perceptions of IAM. Participants attributed more value to art, were more willing to apply IAM, and felt that there was less barriers for applying IAM. The study also indicated differences between art and mathematics preservice teachers' attitudes towards IAM. The differences were due more to art value than willingness or barriers. After the IAM workshop, mathematics preservice teachers put more emphasis on the importance of art to mathematics, especially with respect to making mathematics a more enjoyable subject.
Electrochemical Deposition of Metal Organic-Modified-Ceramic Nanoparticles to Improve Corrosion and Mechanical Properties
Corrosion is an unstoppable process that occurs spontaneously in many areas of industry, specially, oil and gas industries. Therefore, the need of developing protective coating to lower the cost of corrosion is very consistent. Among different methods, electrodeposition has been a popular method since it offer many advantages such as low cost, ability to control the surface and thickness of the coating, ability to perform at low temperature and pressure, and very convenience. Ceramic nanoparticles have been widely incorporated into metal coating and used as a protective layer to improve both corrosion and hardness properties. Diazonium synthesis was used to modify cerium oxide nanoparticles by grafting with ferrocene for use in nickel nanocomposite coating. Citric acid and citrate salt were used as stabilizing ligands for yttrium oxide and praseodymium oxide nanoparticles in nickel plating solution to prevent the formation of hydroxide, thus, higher amount of nanoparticles was able to incorporate into nanocomposite coatings. These fabricated coatings were evaluate for the corrosion and mechanical properties using many different instruments and electrochemical techniques. As modified cerium oxide, stabilized yttrium oxide or praseodymium oxide added into nickel coatings. The results showed an increase in hardness and corrosion resistance leading to the overall improvement compare to pure nickel coating.
Enhancing Storage Dependability and Computing Energy Efficiency for Large-Scale High Performance Computing Systems
With the advent of information explosion age, larger capacity disk drives are used to store data and powerful devices are used to process big data. As the scale and complexity of computer systems increase, we expect these systems to provide dependable and energy-efficient services and computation. Although hard drives are reliable in general, they are the most commonly replaced hardware components. Disk failures cause data corruption and even data loss, which can significantly affect system performance and financial losses. In this dissertation research, I analyze different manifestations of disk failures in production data centers and explore data mining techniques combined with statistical analysis methods to discover categories of disk failures and their distinctive properties. I use similarity measures to quantify the degradation process of each failure type and derive the degradation signature. The derived degradation signatures are further leveraged to forecast when future disk failures may happen. Meanwhile, this dissertation also studies energy efficiency of high performance computers. Specifically, I characterize the power and energy consumption of Haswell processors which are used in multiple supercomputers, and analyze the power and energy consumption of Legion, a data-centric programming model and runtime system, and Legion applications. We find that power and energy efficiency can be improved significantly by optimizing the settings and runtime scheduling of processors, and Legion runtime performs well for larger-scale computation in terms of power and energy consumption.
Ensemble Singing in the Bel Canto Salon Repertory: A Pedagogical Reconsideration
Vocal duets have had a long history in the Western classical music tradition. Their use as a teaching resource can be traced back to the Renaissance, where duets were used for the development of singing, performance, and musicianship. In the late 19th and all of the 20th centuries, this pathway of vocal pedagogy has markedly declined. This study proposes a reintroduction of this methodology of teaching, asserting that it provides the collegiate vocal student with maximum opportunity for growth and development in terms of technique, musicianship, ensemble skills, and performance development. Four vocal duets ("La pesca," "Il brindisi," "Il gallop," and "La caccia") of Saverio Mercadante (1795-1870) serve as the point of discussion. These songs from Les soirées italiennes (C.1836), which are representative of the salon culture of the 19th century, are given detailed attention through a discussion of their pedagogical value. Since they are long out of print, a new performance edition is presented.
An Exploration of Professional Training and Professional Practice: Title IX Administrators and Meaning Making
Federal law requires institutions to designate campus-based administrators to oversee Title IX processes and investigations, but little is known about how these have been professionally prepared for their roles. The purpose of this study was to understand the professional preparation, educational experiences, and professional training of Title IX administrators and to understand their independence in decision-making in those roles. This study utilized qualitative content analysis and a social constructionist approach to analyze data generated from interviews and document analysis. Sixteen current and former Title IX administrators (investigators, deputy coordinators, coordinators) provided their perspectives on their professional training and development. Using frameworks of work/professional socialization and professions theory, findings illustrated complex systems for knowledge acquisition, professional preparation, and professional socialization based on factors including resources, institutional context, and role prioritization. Participants' formal education, formative experiences, position-specific training, and professional organizations training all served as preparation for their roles. Discussion focused on implications for graduate programs, training and trainers, institutions and supervisors, the field of higher education, and current Title IX practitioners regarding professional preparation for these roles.
Exploring EHR Adoption and Implementation: The Impact of Resource Advantage Theory on Healthcare Organization's Competitive Position
The hospitals and their healthcare providers need to optimize simultaneously three outcomes: healthcare costs, healthcare options offered to customers, and information utilization efficiency. The adoption of electronic healthcare record (EHR) technologies is a potential managerial mechanism for balancing these outcomes. EHR offers patient management and decision support capabilities that can ameliorate health delivery outcomes for patients, doctors, and hospitals through better-informed business and care decisions. The analysis of data collected in an EHR system may lower costs and improve health care delivery (or both). In sum, it could be argued that EHR is a source of competitive advantage. Despite this prima facie appeal, many hospitals remain reluctant to adopt and implement EHR due to lack of insights into return on investment, unavailability of tested systems and data entry obstacles. To address this gap between the potential of EHR system and lack of its adoption, the purpose of this research is to investigate the role of EHR as a resource of competitive advantage for hospital. Essay 1, titled "Implementation and Adoption of EHR: A Conceptual Model based on Resource Advantage Theory", describes the antecedents and consequences of EHR adoption and implementation. Essay 2, titled "Exploring the Relationship Between Electronic Healthcare Record Adoption and Quality of Care", delves deeper into the operational performance of a hospital. This essay focuses on the impact of EHR on different aspects of patient care and thereby on the financial performance of the hospital. Essay 3, titled "The Effect of Resources on a Hospital's Financial Performance: The Moderating Role of Electronic Health Records Implementation and Adoption", is an empirical inquiry into the key factors that may influence hospitals' financial performance. These include organizational factors (such as, number of nurses and beds) and environmental factors (such as, location and received donations). Further, this essay explores the interaction effects …
Extrinsic Doping of Few Layered Tungsten Disulfide Films by Pulsed Laser Deposition
This dissertation tested the hypothesis that pulsed laser deposition (PLD) could be used to create targeted dopant profiles in few layered WS2 films based on congruent evaporation of the target. At the growth temperatures used, 3D Volmer-Weber growth was observed. Increased energy transfer from the PLD plume to the growing films degraded stoichiometry (desorption of sulfur) and mobility. Sulfur vacancies act as donors and produce intrinsic n-type conductivity. Post deposition annealing significantly improved the crystallinity, which was accompanied by a mobility increase from 6.5 to 19.5 cm2/Vs. Preparation conditions that resulted in excess sulfur, possibly in the form of interstitials, resulted in p-type conductivity. Current-voltage studies indicated that Ohmic contacts were governed by surface properties and tunneling. Extrinsic p-type doping of few layered WS2 films with Nb via pulsed laser deposition using ablation targets fabricated from WS2, S and Nb powders is demonstrated. The undoped controls were n-type, and exhibited a Hall mobility of 0.4 cm2/Vs. Films doped at 0.5 and 1.1 atomic percentages niobium were p-type, and characterized by Fermi levels at 0.31 eV and 0.18 eV from the valence band edge. That is, the Fermi level moved closer to the valence band edge with increased doping. With increased Nb doping, the hole concentrations increased from 3.9 x1012 to 8.6 x1013 cm-2, while the mobility decreased from 7.2 to 2.6 cm2/Vs, presumably due to increased ionized impurity scattering. X-ray photoelectron spectroscopy indicates that Nb substitutes on W lattice sites, and the measured peak shifts toward lower binding energy observed corresponded well with the UPS data. Throughout, a clear correlation between degraded stoichiometry and decreased mobility was observed, which indicates that point defect and ionized impurity scattering is a dominant influence on carrier transport in PLD few-layered WS2 films. The approach demonstrates the potential of PLD for targeted doping of …
Faculty Characteristics and Program Budgets: Academic Capitalist Influences on Physical Therapy Graduate Outcomes
This study sought to observe the trends in physical therapy faculty members over time and to understand how those trends correlated with changes in program outcomes. Accreditation data from 231 programs between 2008 and 2017 was used in a panel analysis using fixed effects and random effects models to estimate the effects that faculty characteristics, program characteristics, and program budgets have on graduation rates, first-time licensure examination pass rates, and the percentage of graduates of color that a program produced. Results show that for a 1% increase in faculty time devoted to scholarship, a program could expect graduation rates to rise by 0.17%. For a one percentage point increase in grant-funded faculty, a program could expect a 1.7% increase in graduation rates. Results also indicated a negative linear relationship between the number of publications and graduation rates. First-time licensure exam pass rates had an association with different variables. For a 1% increase in part-time faculty, a program could expect a 6.4% decline in first-time licensure examination pass rates. Similarly, a 1% increase in tenured faculty was associated with a 1.2% decline in first-time licensure examination pass rates. A 1% increase in faculty of color was associated with an increase in graduates of color by 33%. This research study provides data to better inform interested parties on how changes in faculty makeup and program budgets can impact PT graduation rates, licensure pass rates, and the percentage of graduates of color that a program can realistically expect to produce.
The Food-Drug Relationship in Health and Medicine
In this dissertation, I apply Gadamerian philosophical hermeneutics to examine interpretations of the food-drug relationship within the contexts of health and medicine. Assumptions regarding the relationship between these categories undergird a substantial academic discourse and function as key components in worldviews beyond the academy. Despite this, little work has been done in foregrounding them to allow for critique and consideration of alternative perspectives. Unearthing philosophical assumptions within various fields, epistemic systems, and regulatory bodies, I classify food-drug interpretations into two main categories: dichotomous interpretations of the categories of "food" and "drugs" as ontologically distinct, and continuum-based interpretations where these categories overlap. Rather than arguing for a single appropriate way of understanding the food-drug relationship, my project aims to disclose the complexities of both sets of interpretations, illustrating their virtues and vices, and underscoring the need for people to call their own interpretations into question while taking seriously those of others. The dialogical structure of philosophical hermeneutics provides a useful foundation for dialogue within and between dichotomous and continuum-based interpretations. We do not have unmediated access to a mind-independent reality, the terms "food" and "drugs" do not necessarily refer to natural kinds, and all interpretations likely have different degrees of strengths and blind spots. Food-drug interpretations are bound up with larger worldviews, holistic systems that generate meaning for their adherents. Granting this, conversation partners can seek to gain a clearer picture of differing interpretations, what they can learn from these interpretations, and how they can interrogate their own interpretive modes.
The Forty-fifth Illinois Volunteer Infantry Regiment: the Washburne Lead Mine Regiment in the Civil War
Of the roughly 3,500 volunteer regiments and batteries organized by the Union army during the American Civil War, only a small fraction has been studied in any scholarly depth. Among those not yet examined by historians was one that typified the western armies commanded by the two greatest Federal generals, Ulysses S. Grant and William T. Sherman. The Forty-fifth Illinois Volunteer Infantry was at Fort Donelson and Shiloh with Grant in 1862, with Grant and Sherman during the long Vicksburg campaign of 1862 and 1863, and with Sherman in the Meridian, Atlanta, Savannah, and Carolinas campaigns in the second half of the war. These Illinois men fought in several of the most important engagements in the western theater of the war and, in the spring of 1865, were present when the last important Confederate army in the east surrendered. The Forty-fifth was also well connected in western politics. Its unofficial name was the “Washburne Lead Mine Regiment,” in honor of U.S Representative Elihu B. Washburne, who used his contacts and influences to arm the regiment with the best weapons and equipment available early in the war. (The Lead Mine designation referred to the mining industry in northern Illinois.) In addition, several officers and enlisted men were personal friends and acquaintances of Ulysses Grant of Galena, Illinois, who honored the regiment for their bravery in the final attempt to break through the Confederate defenses at Vicksburg. The study of the Forty-fifth Illinois is important to the overall study of the Civil War because of the campaigns and battles the unit participated and fought in. The regiment was also one of the many Union regiments at the forefront of the Union leadership’s changing policy toward the Confederate populace and war making industry. In this role the regiment witnessed the impact of President …
Given That the Body Was Made
A collection of poems that explores notions of disability, family, and belief, with a preface that meditates on questions related to the ethical ramifications of various approaches to the making of poetry and art that takes up the suffering of others as subject matter.
A Global Spatial Model for Loop Pattern Fingerprints and Its Spectral Analysis
The use of fingerprints for personal identification has been around for thousands of years (first established in ancient China and India). Fingerprint identification is based on two basic premises that the fingerprint is unique to an individual and the basic characteristics such as ridge pattern do not change over time. Despite extensive research, there are still mathematical challenges in characterization of fingerprints, matching and compression. We develop a new mathematical model in the spatial domain for globally modeling loop pattern fingerprints. Although it is based on the well-known AM-FM (amplitude modulation and frequency modulation) image representation, the model is constructed by a global mathematical function for the continuous phase and it provides a flexible parametric model for loop pattern fingerprints. In sharp contrast to the existing methods, we estimate spatial parameters from the spectral domain by combining the exact values of frequencies with their orientations perpendicular to the fingerprint ridge flow. In addition, to compress fingerprint images and test background Gaussian white noise, we propose a new method based on periodogram spacings. We obtain the joint pdf of these m-dependent random variables at Fourier frequencies and derive the asymptotic distribution of the test statistic.
How the Conflict of Autonomous and Controlled Motivation Influences Sales Controls to Inside Sales Agents' Work Outcomes
Through the use of multiple methodologies and analytical approaches, this dissertation combines (1) sales control; (2) call center service; and (3) motivational theory to extend sales control literature beyond its current state, to consider the conflicting motivational perspectives an inside sales agent has to experience. To achieve this unification, this dissertation consists of three essays intended to: (1) identify the influence of autonomous and controlled motivation on operational sales outcome controls and performance; (2) explore the influence these motivators have on sales controls and sales performance; and, (3) understand the impact of autonomous and controlled motivation on sales agent tenure.
The Impact of Property Tax Exemptions on the Fiscal Behavior of Cities: A Longitudinal Analysis of 41 Texas Cities
As a form of tax and expenditure limitations, property tax exemptions result in an utility gap between two groups of population residing in the same community: free-riders who are paying less than they receive and contributors who are paying more than they receive. This utility gap is problematic to municipalities because contributors may exit the city as this gap becomes wider. How do municipalities respond to the increasing amount of property tax exemptions? Using 41 Texas cities data from 2000 to 2016, this dissertation examines how property tax exemptions affect municipalities' fiscal behavior. The analysis indicates that property tax exemptions lead to higher property tax burden, change municipalities' revenue structure, and lead to less capital spending.
The Impact of Sociocultural and Information Communication Technology Adoption Factors on the Everyday Life Information Seeking Behavior of Saudi Students in the United States
This study analyzes the sociocultural factors that affect Saudi students in the U.S. as they seek information and explores to what extent these factors impact their everyday life information seeking (ELIS) behavior and their information technology behavior (ITB). The factors in this study illustrate the unique sociocultural values that distinguish Saudi students from other international student groups: gender segregation, emphasis on religion, social support, and utilization of the consultation concept. After collecting data from an online survey, the data from linear regression analyses revealed that only one culture factor (the language barrier) showed a significant impact on Saudi student ELIS in the U.S., while the other factors were not statistically significant. Also, the findings indicated that perceived usefulness (PU) and perceived ease of use (PEU) were statistically significant to the ELIS of Saudi students. Furthermore, the study showed that after academic information, food and drink, entertainment, and health were the top student needs, the top ranking sources for everyday life seeking information were social media and the Internet. The findings of the study help to shed light on a sizable user group. As the fourth largest group of international students in the U.S., Saudi students have been underrepresented in research. Also, the study's findings and recommendations provide a more profound understanding of Saudi students for both the hosting American university officials and stakeholders who provide scholarships.
Improving Actigraphy Specificity to Better Inform Insomnia Diagnosis and Treatment Decisions
Accurate assessment of sleep-wake patterns is important for sleep researchers and clinicians. Actigraphs are low-cost, non-intrusive, wrist-worn activity detectors used to estimate sleep-wake patterns in a natural environment for several nights. Although actigraphy shows good sensitivity (sleep detection), it has consistently demonstrated poor specificity (wakefulness detection while lying in bed relatively motionless). Because insomnia is characterized by wakefulness in bed, actigraphy may not be a valid objective measure of wakefulness for this group. It is possible that refinement of actigraphy software settings for sleep/wake algorithms might improve specificity. The current studies investigated this hypothesis by comparing wake parameters from 48 combinations of actigraphy settings to determine which sleep/wake algorithms best inform insomnia diagnosis and treatment. In the first study, none of the 48 actigraphy setting combinations consistently discriminated between adults with insomnia (n = 69) and non-insomnia (n = 80) on all three wake parameters, and no setting clearly discriminated between groups for the composite variable, total wake time. Similarly, in the second study, no setting combinations consistently discriminated between adults treated for insomnia (n = 18) and controls with untreated insomnia (n = 26) on all three wake parameters. Although two setting combinations discriminated between groups for the composite variable, total wake time, the values were extreme which raises validity concerns. Therefore, no actigraphy setting recommendations can be made based on the current findings. This research offers insights about the effects of actigraphy software settings on actigraphy specificity as it pertains to the diagnosis and treatment of insomnia.
Information Sharing and Storage Behavior via Cloud Computing: Security and Privacy in Research and Practice and Users' Trust
This research contributes to the cloud computing (CC) literature and information science research by addressing the reality of information sharing and storage behavior (ISSB) of the users' personal information via CC. Gathering information about usage also allows this research to address the paradox between the research and practice. Additionally, this research explores the concept of trust and its role in the behavioral change relative to CC. The findings help reconcile the paradox between the two realms. Essay1 develops and tests cloud computing usage model (CCUM) that assesses ISSB. This model considers the main adoption determinants and the main drawbacks of CC. The study measures the main concerns of users found in the literature, perceived security and perceived privacy. The findings prove surprising on these concerns. Using multiple regression to analyze 129 valid survey responses, the results find that CC users are less concerned about the major issues of security and privacy and will use the technology based on peer usage. Essay 2 examines why users ignore the technology issues and elect to replace the traditional mechanisms for handling their personal information. The results of an interview-based study conducted on 11 normal users and 11 IT professionals clarify their perceptions about CC and examine its readiness to handle their information from an end-user perspective. Essay 3 explores the CC literature to identify the major factors associated with the users' trust beliefs. The research conducted in this essay groups these factors into three categories. The posited and tested model examines the effect of perceived trust on ISSB. A structural equation modeling approach is used to analyze 1228 valid responses and tests the developed cloud computing trust model. The results provide multiple implications for CC researchers, managers, and service providers.
An Investigation of Multiple Articulation as Applied to Saxophone Literature and Its Performance: An Historical and Pedagogical Approach
Multiple articulation is a technique that is becoming commonplace in the saxophone literature. This study provides a detailed explanation of how produce the technique. Its application to saxophone literature is explored with musical examples and commentary by the author. A compilation of pedagogical viewpoints regarding multiple articulation from educators spanning the last century is provided.
Investigations of the Fresnel Lens Based Solar Concentrator System through a Unique Statistical-Algorithmic Approach
This work investigates the Fresnel-lens-based solar concentrator-receiver system in a multi-perspective manner to design, test and fabricate this concentrator with high-efficiency photon and heat outputs and a minimized effect of chromatic aberrations. First, a MATLAB®-incorporated algorithm optimizes both the flat-spot and the curved lens designs via a statistical ray-tracing methodology of the incident light, considering all of its incidence parameters. The target is to maximize the solar ray intensity on the receiver's aperture, and therefore, achieve the highest possible focal flux. The algorithm outputs prismatic and dimensional geometries of the Fresnel-lens concentrator, which are simulated by COMSOL® Multiphysics to validate the design. For the second part, a novel genetically-themed hierarchical algorithm (GTHA) has been investigated to design Fresnel-lens solar concentrators that match with the distinct energy input and spatial geometry of various thermal applications. Basic heat transfer analysis of each application decides its solar energy requirement. The GTHA incorporated in MATLAB® optimizes the concentrator characteristics to secure this energy demand, balancing a minimized geometry and a maximized efficiency. Two experimental applications were selected from literature to validate the optimization process, a solar welding system for H13 steel plates and a solar Stirling engine with an aluminum-cavity receiver attached to the heater section. In each case, a flat Fresnel-lens with a spot focus was algorithmically designed to supply the desired solar heat, and then a computer simulation of the optimized lens was conducted showing great comparability to the original experimental results. Thirdly, the prismatic geometry of the Fresnel lens was further optimized through a statistical approach that incorporates laws of light refraction and trigonometry. The proposed design produces high focal irradiance that is more suitable for thermal applications. The motivation was to enhance the tolerability of a flat Fresnel-lens concentrator to tracking errors, without the use of secondary optics or sophisticated, …
John La Montaine's "Songs of the Rose of Sharon" and "Fragments from the Song of Songs": A Socio-Historical Analysis and Performer's Guide
The purpose of this research is to examine John La Montaine's only two song cycles for soprano and orchestra, Songs of the Rose of Sharon, opus 6 (1947) and Fragments from the Song of Songs, opus 29 (1959). In this investigation-the first ever specific to these works-I examine the works and cultural context in which they were created. I then evaluate the reasonable possibility that La Montaine used his public platform as a composer and performer to subtly celebrate taboo themes of feminism, sexuality, and blackness while shining a light on human injustice. Through close examination of social and historical context, I argue two points. Firstly, Rose of Sharon and Fragments are landmark American works. They are anomalies in classical music history in that a white male heralds texts about a black woman in an unlikely time in American history, thus arguably becoming an unlikely part of the evolution of African-American women in artistic endeavors. Secondly, in the performance guide, I advocate that these works would readily adapt to a staged performance. I discuss how La Montaine's musical settings illustrate the inherent drama of the text, provide a context for interpreting the protagonist in Rose of Sharon and Fragments, and present an interpretation of how these works could be staged. The ultimate goal of this research is to bring these intricately crafted masterpieces to the attention of singers and voice teachers so that they may assume their rightful place in the repertoire.
The Last Karankawas: Stories
A collection of interconnected short stories set in diverse corners of Texas, converging on Galveston Island before and after Hurricane Ike.
Ligand Effects in Gold(I) Acyclic Diaminocarbene Complexes and Their Influence on Regio- and Enantioselectivity of Homogeneous Gold(I) Catalysis
This dissertation focuses on the computational investigation of gold(I) acyclic diaminocarbene (ADC) complexes and their application in homogeneous gold(I) catalysis. Chapter 2 is an in-depth computational investigation of the σ- and π-bonding interactions that make up the gold-carbene bond. Due to the inherent conformation flexibility of ADC ligands, distortions of the carbene plane can arise that disrupt orbital overlap between the lone pairs on the adjacent nitrogen atoms and the empty p-orbital of the carbene. This study investigated the affect these distortions have on the strength of the σ- and π-bonding interactions. This investigation demonstrated that while these distortions can affect the σ- and π-bonding interactions, the ADC ligand have to become highly distorted before any significant change in energy of either the σ- or π-bonding interactions occurs. Chapter 3 is a collaborative investigation between experimental and computational methods, DFT calculations were employed to support the experimental catalytic results and determine the role that steric effects have in controlling the regioselectivity of a long-standing electronically controlled gold(I)-catalyzed tandem 1,6-enyne cyclization/hydroarylation reaction with indole. This study demonstrated that by sterically hindering nucleophilic attack of indole at the favored position, nucleophilic attack would occur at a secondary position leading to the selective formation of the electronically unfavored product. Chapter 4 is a collaborative investigation between experimental and computational methods. DFT calculations were employed to investigate and rationalize the importance of secondary non-covalent interactions and their influence on the enantioselectivity of a gold(I)-catalyzed intramolecular hydroamination of allene reaction. Through computational investigation of the enantiodetermining step, and the non-covalent interactions present between 2′-aryl substituent and the rest of the catalyst, it was determined that the presence of CF3 group on the 3,5-position of the 2′-aryl ring is crucial to maintaining a more rigid chiral pocket leading to higher enantiomeric excesses in this dynamic system. …
Linking Enhanced Fatigue Life to Design by Modifying the Microstructure
Structural material fatigue is a leading cause of failure and has motivated fatigue-resistant design to eliminate risks to human lives. Intrinsic microstructural features alter fatigue deformation mechanisms so profoundly that, essentially, fatigue properties of structural materials become deviant. With this in mind, we initiated this project to investigate the microstructural effect on fatigue behavior of potential structural high entropy alloys. With a better understanding of the effect of microstructure features on fatigue properties, the ultimate goal was to engineer the microstructure to enhance the fatigue life of structural materials. The effects of two major deformation mechanisms presented here are twinning-induced fatigue crack retardation, and transformation-induced fatigue crack retardation. The fundamental principle of both mechanisms is to delay the fatigue crack propagation rate by altering the work hardening ability locally within the crack plastic zone. In ultrafine grained triplex Al0.3CoCrFeNi, nano-sized deformation twins were observed during cyclic loading in FCC matrix due to low stacking fault energy (SFE). The work-hardening ability of the material near the crack was sustained with the formation of twins according to Considere's criteria. Further, due to the ultrafine-grained (UFG) nature of the material, fatigue runout stress was enhanced. In a coarse-grained, dual-phase high entropy alloy, persistent slip bands formed in FCC matrix during cyclic loading due mainly to the slight composition change that affects the SFE in the FCC matrix and eventually alters the deformation mechanism. Another way known to alter an alloy's work hardening (WH) ability is transformation-induced plasticity (TRIP). In some alloys, phase transformation happens due to strain localization, which alters the work-hardening ability. iii In a fine-grained, dual-phase metastable high entropy alloy, gamma (f.c.c.) to epsilon (h.c.p.) transformation occurred in the plastic zone that was induced from cracks. Thus, we designed a Cu-containing FeMnCoCrSi high entropy alloy that exhibited a normalized fatigue ratio …
Luigi Boccherini's Cello Concerto in B-Flat Major, G.482: Creating a Performance Edition through a Critical Study of the 'Original' Version and Friedrich Grützmacher's Edition
The Cello Concerto in B-flat major, G.482, by Italian composer Luigi Boccherini (1743-1805), is the composer's most beloved work for the instrument, as well as one of the most performed pieces in the Classical concerto repertoire. Historically, cellists performing this work have used an edition prepared by German cellist Friedrich Grützmacher (1832-1903). However, an 'original' version that was discovered in 1949 is significantly different from that of Grützmacher. A comparison of both editions has revealed that Grützmacher in fact made considerable modifications to Boccherini's 'original.' Along with the issue of having two editions, cellists that have played the 'original' edition have noted that there are certain practical and interpretative matters that are not favorable to the cellist, particularly in terms of the way the music is notated and how it lacks many details. This dissertation provides clarity to these issues by undertaking a comprehensive analysis of both editions in order to make cellists become aware of the differences between both editions by comparing musical elements from a performance practice viewpoint. In addition, I discuss relevant issues that are present in the 'original' version, ultimately providing an alternative performance edition to this score that is based on historically informed performance (HIP) practices. Finally, I hope to draw attention on how a performance edition like this can be useful as a rare critical source to one of the major works from the eighteenth-century cello repertoire.
Manipulation of Light-Matter Interactions in Molybdenum Disulfide (MoS2) Monolayer through Dressed Phonons (DP) and Plasmons
The performance of electrical and optical devices based on two-dimensional semiconductors (2D) such as molybdenum disulfide is critically influenced due to very poor light absorption in the atomically thin layers. In this study, the phonon mediated optical absorption and emission properties in single atomic layers of MoS2 have been investigated. The electronic transitions in MoS2 due to near-field optical interaction and the influence of interface phonons due to the dielectric substrate GaN on the relaxation of optically generated carriers will be described. The near-field interaction can be induced in the presence of metal plasmons deposited on the surface of MoS2 monolayers. A hybrid metal-semiconductor system was realized by the deposition of silver (Ag) NPs on MoS2 layer and the localized plasmon modes were selectively chosen to interact with quasiparticles such as excitons and phonons. These quasiparticles are confined within the single atomic layer of MoS2 and are stable at room temperatures due to high binding energy. The lattice vibrational modes in MoS2 can be optically excited with the pulses from a femtosecond laser. These phonon modes can be optically dressed due to near-field interaction in the hybrid Ag-MoS2 system under an optical excitation resonant to localized plasmon modes. The coherent dynamics of the carriers in MoS2 were manipulated by the generation of dressed phonons. The driving field creates a coherence between the ground levels in the presence of optical near-field. A strong coupling between the exciton and plasmon modes forming a plexciton band is observed at room temperature within the coherence lifetime of the system. A significant enhancement of photoluminescent (PL) emission from MoS2 monolayer occurs due to carrier density modulation in the presence near-field interactions. The absorption and emission properties of MoS2 are influenced due to the interactions with the semiconducting substrate. The coupling of carriers in MoS2 with …
Measurement of Positive Continuance Intention Drivers within a Service Domain
The contribution of this dissertation is how model measurement allows examination of the balance between what is practical in terms of consumer concerns versus what is optimal in terms of cost control. Essay 1 examines a research framework that incorporates various service recovery strategies and simultaneously evaluates their comparative influences. Essay 2 evaluates the complex interrelationships among different factors related to the post-complaint behavioral process. Essay 3 fills a research gap by examining the role of brand equity by operationalizing a reflective model using PLS in operations management (OM) research. These three essays provide insight into the quality management domain and the value that is achieved via a data driven examination of theory. Moreover, this research will provide operations management practitioners a basis to carry out future research on quality management phenomena as well as insight into how to balance cost control and service recovery strategies with the goal of achieving a competitive advantage.
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