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Computational Imaging Systems For High-Speed, Adaptive Sensing Applications, Yangyang Sun Jan 2019

Computational Imaging Systems For High-Speed, Adaptive Sensing Applications, Yangyang Sun

Electronic Theses and Dissertations

Driven by the advances in signal processing and ubiquitous availability of high-speed low-cost computing resources over the past decade, computational imaging has seen the growing interest. Improvements on spatial, temporal, and spectral resolutions have been made with novel designs of imaging systems and optimization methods. However, there are two limitations in computational imaging. 1), Computational imaging requires full knowledge and representation of the imaging system called the forward model to reconstruct the object of interest. This limits the applications in the systems with a parameterized unknown forward model such as range imaging systems. 2), the regularization in the optimization process …

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Discovering Latent Gender Bias In Children's Stem Literature, Christine Herlihy Jan 2019

Discovering Latent Gender Bias In Children's Stem Literature, Christine Herlihy

Electronic Theses and Dissertations

A mixed method, exploratory, sequential research design was conducted to investigate the presence of latent bias in early childhood STEM literature content, applying a non-biased, sociocultural, STEM identity, theoretical framework. A survey of children's perceptions of gender and a content analysis found unintentional bias. Exploratory findings confirmed 102 children were gendering images. An examination of the relationship between the participants' gender and how the participant gendered AND preferred the images indicated differences existed between boys and girls. Children preferred images perceived as matching their own, with statistical significance. Girls were found to prefer images less than boys AND they were …

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The Characterization Of Condom Lubricants And Personal Hygiene Products Using Dart-Tofms And Gc- Ms And The Investigation Of Gold Nanoparticle Behavior In Water And The Interaction With Blood Serum Proteins, Yasmine Moustafa Jan 2019

The Characterization Of Condom Lubricants And Personal Hygiene Products Using Dart-Tofms And Gc- Ms And The Investigation Of Gold Nanoparticle Behavior In Water And The Interaction With Blood Serum Proteins, Yasmine Moustafa

Electronic Theses and Dissertations

This dissertation is divided into two independent research projects. First, condom lubricants, sexual lubricants, and personal hygiene products (PHPs) were studied using direct analysis in real time-time-of-flight-mass spectrometry (DART-TOFMS) and gas chromatography-mass spectrometry (GC-MS). The purpose addressed the concern of perpetrators resorting to new tactics, i.e. using condoms to remove seminal fluid that could provide a DNA link to a suspect, leading to the need of the consideration of condom lubricants as pieces of sexual assault evidence. Due to condom lubricants having a chemical composition resembling PHPs, the investigation of both sample groups was analyzed to prevent false positives. Although …

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Cryogenic Performance Projections For Ultra-Small Oxide-Free Vertical-Cavity Surface-Emitting Lasers, Mina Bayat Jan 2019

Cryogenic Performance Projections For Ultra-Small Oxide-Free Vertical-Cavity Surface-Emitting Lasers, Mina Bayat

Electronic Theses and Dissertations

Small-sized vertical-cavity surface-emitting laser (VCSEL) may offer very low power consumption along with high reliability for cryogenic data transfer. Cryogenic data transfer has application in supercomputers and superconducting for efficient computing and also focal plane array cameras operating at 77 K, and at the lower temperature of 4 K for data extraction from superconducting circuits. A theoretical analysis is presented for 77 K and 4 K operation based on small cavity, oxide-free VCSEL sizes of 2 to 6 µm, that have been shown to operate efficiently at room temperature. Temperature dependent operation for optimally-designed VCSELs are studied by calculating the …

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Design And Fabrication Of Scalable Multifunctional Multimaterial Fibers And Textiles, Felix Tan Jan 2019

Design And Fabrication Of Scalable Multifunctional Multimaterial Fibers And Textiles, Felix Tan

Electronic Theses and Dissertations

Multimaterial fibers eschew the traditional mono-material structures typical of traditional optical fibers for novel internal architectures that combine disparate materials with distinct optical, mechanical, and electronic properties, thereby enabling novel optoelectronic functionalities delivered in the form factor of an extended fiber. This new class of fibers developed over the past two decades is attracting interest from researchers in such different fields as optics, textiles, and biomedicine. The juxtaposition of multiple materials integrated at micro- and nanoscales in complex geometries while ensuring intimate smooth interfaces extending continuously for kilometers facilitates unique applications such as non-invasive laser surgery, self-monitoring fibers, e-textiles, and …

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Stable, Highly Luminescent Perovskite-Polymer Composites For Photonics Applications, Juan He Jan 2019

Stable, Highly Luminescent Perovskite-Polymer Composites For Photonics Applications, Juan He

Electronic Theses and Dissertations

Metal halide perovskites (simplified as perovskites as below), particularly those in nanocrystal forms, have recently emerged as highly efficient, bandgap tunable photonics materials that can be easily solution processed at low cost for display, lighting or other energy conversion applications. However, the quick degradation of perovskite nanocrystals under external stresses or upon colloidal aggregations has been a major challenge for most applications where high reliability is normally required. In this thesis, we have explored a polymer swelling-deswelling microencapsulation (SDM) process that enables the dispersion, in-situ crystallization and subsequent surface passivation of perovskite nanocrystals in polymer matrices, and leads to ultrastable …

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Computational Imaging With Limited Photon Budget, Zheyuan Zhu Jan 2019

Computational Imaging With Limited Photon Budget, Zheyuan Zhu

Electronic Theses and Dissertations

The capability of retrieving the image/signal of interest from extremely low photon flux is attractive in scientific, industrial, and medical imaging applications. Conventional imaging modalities and reconstruction algorithms rely on hundreds to thousands of photons per pixel (or per measurement) to ensure enough signal-to-noise (SNR) ratio for extracting the image/signal of interest. Unfortunately, the potential of radiation or photon damage prohibits high SNR measurements in dose-sensitive diagnosis scenarios. In addition, imaging systems utilizing inherently weak signals as contrast mechanism, such as X-ray scattering-based tomography, or attosecond pulse retrieval from the streaking trace, entail prolonged integration time to acquire hundreds of …

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Optical Sensing Of Structural Dynamics In Complex Media, Jose Rafael Guzman Sepulveda Jan 2019

Optical Sensing Of Structural Dynamics In Complex Media, Jose Rafael Guzman Sepulveda

Electronic Theses and Dissertations

Quantifying the structural dynamics of complex media is challenging because of the multiple temporal and spatial scales involved. Thanks to the ability to retrieve collective dynamics noninvasively, light scattering-based approaches are often the methods of choice. This dissertation discusses specific features of dynamic light scattering that utilizes spatio-temporal coherence gating. It is demonstrated that this optical fiber-based approach can operate over a large range of optical regimes and it has a number of unique capabilities such as an effective isolation of single scattering, a large sensitivity, and a high collection efficiency. Moreover, the approach also provides means for proper ensemble …

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Tumor-Targeted Conjugated Polymer Nanoparticles With Encapsulated Iron And Its Biomedical Application For In Vitro Killing Of Melanoma Cell Lines Through Ferroptosis Assisted Chemodynamic Therapy (Cdt), Khalaf Jasim Jan 2019

Tumor-Targeted Conjugated Polymer Nanoparticles With Encapsulated Iron And Its Biomedical Application For In Vitro Killing Of Melanoma Cell Lines Through Ferroptosis Assisted Chemodynamic Therapy (Cdt), Khalaf Jasim

Electronic Theses and Dissertations

Melanoma represents one of the most aggressive and lethal forms of skin cancer, with annually rising incidences throughout the world. Although chemotherapy modalities remain the mainstay of treatment, the therapeutic potential of chemotherapy typically is hampered by multidrug resistance (MDR) and nonspecific drug distribution that causes side-effects. To surmount such limitations, novel nanoformulations of low band-gap poly ({4,8-bis [(2-ethylhexyl) oxy] benzo [1,2-b:4,5-b?] dithiophene-2,6-diyl}{3-fluoro-2-[(2-ethylhexyl) carbonyl] thieno [3,4-b] thiophenediyl}) (PTB7) and poly [2,1,3-benzothiadiazole- 4,7- diyl [4,4-bis (2-ethylhexyl)- 4H-cyclopenta [2,1-b:3,4-b'] dithiophene-2,6-diyl]] (PCPDTBT) were fabricated by a reprecipitation method. These conjugated polymer nanoparticles were functionalized with the polypeptide endothelin-3 (EDN3-CPNPs) to target melanoma. The …

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Structure Of Reflectin Protein Probed By Solid-State Nuclear Magnetic Resonance, Tommy Boykin Jan 2019

Structure Of Reflectin Protein Probed By Solid-State Nuclear Magnetic Resonance, Tommy Boykin

Electronic Theses and Dissertations

An unusual protein found in squids, termed reflectin, possesses the unique ability for optical reflectivity and proton conductivity. Reflectin has the potential to become optically and electronically tunable, however, the molecular structure of reflectin has yet to be determined. Previous literature has considered using reflectin proteins as diffraction gratings, protonic transistors, and substrates for neural stem cell growth. Applying recombinant protein techniques, we purified the reflectin 4Ax4 protein. We determined the leucine, tryptophan, and threonine amino acids are in an ordered state by solid-state nuclear magnetic resonance (NMR). Knowing these ordered amino acids is possibly the key to understanding reflectin's …

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Kindergarten Is Not Child's Play: An Exploration Of Pedagogical Approaches Related To Learning In A Play-Based And A Contemporary Classroom At A Title I Elementary School, Karyn Allee-Herndon Jan 2019

Kindergarten Is Not Child's Play: An Exploration Of Pedagogical Approaches Related To Learning In A Play-Based And A Contemporary Classroom At A Title I Elementary School, Karyn Allee-Herndon

Electronic Theses and Dissertations

This dissertation is divided into three separate, related, naturalistic, quasi-experimental research studies, all using data from two kindergarten classes at Gator Elementary, a public Title I elementary school in Sunshine District in Central Florida. Each of these studies tested hypotheses that kindergarten children, especially those from low socioeconomic backgrounds, will show greater gains in receptive vocabulary, executive function, and academic achievement when purposeful play is used as a pedagogical approach than similar children in typical, contemporary kindergarten classrooms. The first study explored the effects of play-based and contemporary pedagogical approaches on students' receptive vocabulary using the PPVT-4, the second explored …

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Spectral Properties Of The Finite Hilbert Transform On Two Adjacent Intervals Via The Method Of Riemann-Hilbert Problem, Elliot Blackstone Jan 2019

Spectral Properties Of The Finite Hilbert Transform On Two Adjacent Intervals Via The Method Of Riemann-Hilbert Problem, Elliot Blackstone

Electronic Theses and Dissertations

In this dissertation, we study a self-adjoint integral operator $\hat{K}$ which is defined in terms of finite Hilbert transforms on two adjacent intervals. These types of transforms arise when one studies the interior problem of tomography. The operator $\hat{K}$ possesses a so-called "integrable kernel'' and it is known that the spectral properties of $\hat{K}$ are intimately related to a $2\times2$ matrix function $\Gamma(z;\lambda)$ which is the solution to a particular Riemann-Hilbert problem (in the $z$ plane). We express $\Gamma(z;\lambda)$ explicitly in terms of hypergeometric functions and find the small $\lambda$ asymptotics of $\Gamma(z;\lambda)$. This asymptotic analysis is necessary for the …

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Modeling Disease Impact Of Vibrio-Phage Interactions, Christopher Botelho Jan 2019

Modeling Disease Impact Of Vibrio-Phage Interactions, Christopher Botelho

Electronic Theses and Dissertations

Since the work of John Snow, scientists and medical professionals have understood that individuals develop cholera by means of consuming contaminated water. Despite the knowledge of cholera's route of infection, many countries have experienced and still experience endemic cholera. Cholera is caused by the Vibrio cholerae (V. cholerae) bacterium and presents with acute diarrhea and vomiting. If untreated, infected individuals may die due to dehydration. Cholera is a disease that most commonly affects countries with poor infrastructure and water sanitation. Despite efforts to control cholera in such countries, the disease persists. One such example is Haiti which has been experiencing …

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Hybrid Integration Of Second- And Third-Order Highly Nonlinear Waveguides On Silicon Substrates, Guillermo Fernando Camacho Gonzalez Jan 2019

Hybrid Integration Of Second- And Third-Order Highly Nonlinear Waveguides On Silicon Substrates, Guillermo Fernando Camacho Gonzalez

Electronic Theses and Dissertations

In order to extend the capabilities and applications of silicon photonics, other materials and compatible technologies have been developed and integrated on silicon substrates. A particular class of integrable materials are those with high second- and third-order nonlinear optical properties. This work presents contributions made to nonlinear integrated photonics on silicon substrates, including chalcogenide waveguides for over an octave supercontinuum generation, and rib-loaded thin-film lithium niobate waveguides for highly efficient second-harmonic generation. Through the pursuit of hybrid integration of the two types of waveguides for applications such as on-chip self-referenced optical frequency combs, we have experimentally demonstrated fabrication integrability of …

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Semi-Analytical Solutions Of Non-Linear Differential Equations Arising In Science And Engineering, Mangalagama Dewasurendra Jan 2019

Semi-Analytical Solutions Of Non-Linear Differential Equations Arising In Science And Engineering, Mangalagama Dewasurendra

Electronic Theses and Dissertations

Systems of coupled non-linear differential equations arise in science and engineering are inherently nonlinear and difficult to find exact solutions. However, in the late nineties, Liao introduced Optimal Homotopy Analysis Method (OHAM), and it allows us to construct accurate approximations to the systems of coupled nonlinear differential equations. The drawback of OHAM is, we must first choose the proper auxiliary linear operator and then solve the linear higher-order deformation equation by spending lots of CPU time. However, in the latest innovation of Liao's "Method of Directly Defining inverse Mapping (MDDiM)" which he introduced to solve a single nonlinear ordinary differential …

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Preservice Teachers And Perceived Stress: A Comparative Study, Kelsey Evans Jan 2019

Preservice Teachers And Perceived Stress: A Comparative Study, Kelsey Evans

Electronic Theses and Dissertations

Teachers are being pushed to the brink of burnout and leaving the profession, placing teachers' health and wellness in jeopardy (Daniels & Strauss, 2009; Maslach & Leiter, 2008; Stephenson, 2012; Vladut & Kallay, 2010; Wilkerson, 2009). Yet, it has become increasingly clear teacher stress may start prior to entering the profession (Brown & Ryan, 2003, Darling-Hammond, 2006). The researcher used a non-experimental design to evaluate the perceived stress among pre-service teachers enrolled in internship, and if the coping style of mindfulness had any correlation on self-reported stress levels. The quantitative study surveyed 332 student interns using the Perceived Stress Survey …

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Mathematical Investigation Of The Spatial Spread Of An Infectious Disease In A Heterogeneous Environment, Arielle Gaudiello Jan 2019

Mathematical Investigation Of The Spatial Spread Of An Infectious Disease In A Heterogeneous Environment, Arielle Gaudiello

Electronic Theses and Dissertations

Outbreaks of infectious diseases can devastate a population. Researchers thus study the spread of an infection in a habitat to learn methods of control. In mathematical epidemiology, disease transmission is often assumed to adhere to the law of mass action, yet there are numerous other incidence terms existing in the literature. With recent global outbreaks and epidemics, spatial heterogeneity has been at the forefront of these epidemiological models. We formulate and analyze a model for humans in a homogeneous population with a nonlinear incidence function and demographics of birth and death. We allow for the combination of host immunity after …

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Frames And Phase Retrieval, Ted Juste Jan 2019

Frames And Phase Retrieval, Ted Juste

Electronic Theses and Dissertations

Phase retrieval tackles the problem of recovering a signal after loss of phase. The phase problem shows up in many different settings such as X-ray crystallography, speech recognition, quantum information theory, and coherent diffraction imaging. In this dissertation we present some results relating to three topics on phase retrieval. Chapters 1 and 2 contain the relevant background materials. In chapter 3, we introduce the notion of exact phase-retrievable frames as a way of measuring a frame's redundancy with respect to its phase retrieval property. We show that, in the d-dimensional real Hilbert space case, exact phase-retrievable frames can be of …

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Holographic Optical Elements For Visible Light Applications In Photo-Thermo-Refractive Glass, Fedor Kompan Jan 2019

Holographic Optical Elements For Visible Light Applications In Photo-Thermo-Refractive Glass, Fedor Kompan

Electronic Theses and Dissertations

This dissertation reports on design and fabrication of various optical elements in Photo-thermo-refractive (PTR) glass. An ability to produce complex holographic optical elements (HOEs) for the visible spectral region appears very beneficial for variety of applications, however, it is limited due to photosensitivity of the glass confined within the UV region. First two parts of this dissertation present two independent approaches to the problem of holographic recording using visible radiation. The first method involves modification of the original PTR glass rendering it photosensitive to radiation in the visible spectral region and, thus, making possible the recording of holograms in PTR …

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Science Occupational Images And Aspirations Of African American/ Black Elementary Students, Saron Lamothe Jan 2019

Science Occupational Images And Aspirations Of African American/ Black Elementary Students, Saron Lamothe

Electronic Theses and Dissertations

Within the United States, more than a million jobs in science and engineering (S&E) are projected over the next few years; yet, the Nation lacks the workforce to meet these demands. Despite the need for a more diverse, qualified workforce, African Americans/Blacks remain disproportionately underrepresented in science occupations, science degree attainment, and in science postsecondary majors. The lack of science participation is reflective of how minority secondary students view science and science occupations as many consider the pursuit of a science career as unfavorable. Moreover, minority secondary students, who do choose to pursue science occupations, seem to possess inaccurate (or …

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Third-Order Optical Nonlinearities For Integrated Microwave Photonics Applications, Marcin Malinowski Jan 2019

Third-Order Optical Nonlinearities For Integrated Microwave Photonics Applications, Marcin Malinowski

Electronic Theses and Dissertations

The field of integrated photonics aims at compressing large and environmentally-sensitive optical systems to micron-sized circuits that can be mass-produced through existing semiconductor fabrication facilities. The integration of optical components on single chips is pivotal to the realization of miniature systems with high degree of complexity. Such novel photonic chips find abundant applications in optical communication, spectroscopy and signal processing. This work concentrates on harnessing nonlinear phenomena to this avail. The first part of this dissertation discusses, both from component and system level, the development of a frequency comb source with a semiconductor mode-locked laser at its heart. New nonlinear …

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The Sustained Impact Of Prekindergarten Participation On Third Grade Academic Performance, Marissa Melin Jan 2019

The Sustained Impact Of Prekindergarten Participation On Third Grade Academic Performance, Marissa Melin

Electronic Theses and Dissertations

In this study, the researcher investigated whether the impact of participating in a prekindergarten program on academic achievement persists through third grade. The study compared three groups of students: students who participated in voluntary prekindergarten, private prekindergarten, and students who did not participate in any prekindergarten program. Using a series of two-factor multivariate analyses of variance (MANOVAs), this investigation found no interaction effects among prekindergarten participation and race, gender, socioeconomic status, presence of a discipline referral, or chronic absenteeism on academic achievement in the third grade. However, there was a main effect for the type of prekindergarten program on academic …

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An Investigation Of The Appropriateness Of The English Language Learner Accountability Mark Established By The Every Student Succeeds Act Of 2015, Francisco Rivera Jan 2019

An Investigation Of The Appropriateness Of The English Language Learner Accountability Mark Established By The Every Student Succeeds Act Of 2015, Francisco Rivera

Electronic Theses and Dissertations

This quantitative study sought to disclose and describe differences in academic performance between English language learners (ELLs) and non-English language learners (non-ELLs) in grades sixth, seventh, and eighth during the two-year period of 2016 – 2018. A two-year period was utilized because of the two-year ELL accountability mark established by the Every Student Succeeds Act (ESSA) of 2015. The study used i-Ready diagnostic data, in both mathematics and reading, as the performance measures, and used ACCESS for ELLs (WIDA) tier scores (i.e., WIDA Tier A, WIDA Tier B, and WIDA Tier C) to identify the level of English language acquisition …

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Electing Or Appointing School District Superintendents In The State Of Florida: A Comparison Of Characteristics And Performance Of Districts Led By Elected Superintendents Versus Districts Led By Appointed Superintendents, Timothy Smith Jan 2019

Electing Or Appointing School District Superintendents In The State Of Florida: A Comparison Of Characteristics And Performance Of Districts Led By Elected Superintendents Versus Districts Led By Appointed Superintendents, Timothy Smith

Electronic Theses and Dissertations

Florida and Alabama are the only two states in the United States of America with school districts led by either elected superintendents or appointed superintendents. The other 48 states only have appointed superintendent-led school districts. The current study was conducted to examine the impact of the superintendent governance structure on student learning by analyzing differences in student achievement between Florida school districts led by elected superintendents and Florida school districts led by appointed superintendents. The conceptual framework of the study was the tension between democratic localism and professionalism. Dynamics associated with the conceptual framework are relevant to the current debate. …

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A Phenomenological Study Of High School Assistant Principals Who Supervise Special Education, Erin Vacchio Jan 2019

A Phenomenological Study Of High School Assistant Principals Who Supervise Special Education, Erin Vacchio

Electronic Theses and Dissertations

This phenomenological study examined the lived experiences of high school assistant principals who lead the Exceptional Student Education (ESE) departments at their respective schools. The role of the school leader is critical and complex. Second to only the classroom teachers, school leaders have the ability to shape the school wide attitude and vision for students with disabilities. Knowing that in the past 30 years, the number of students with disabilities has nearly doubled in size, the expertise of school leaders in special education must also increase. Research on the experiences of high school administrators who serve students with intellectual disabilities …

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Phenomenological Study Of Urban Elementary Teachers With Proficient English Language Learners, Tracy Webley Jan 2019

Phenomenological Study Of Urban Elementary Teachers With Proficient English Language Learners, Tracy Webley

Electronic Theses and Dissertations

The purpose of this qualitative, phenomenological study was to explore the lived experiences of fourth grade teachers working in a large urban school district, where the achievement gap between English Language Learners (ELLs) and non-ELLs was smaller when compared to other schools within the district. The problem originated from the need to consider factors beyond teacher training that potentially influenced academic achievement. The research question guiding this study asked: What are the lived experiences of 4th grade teachers who have taught at identified elementary schools, where ELL students have demonstrated proficiency on the ELA portion of the state standards assessment? …

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Analyzing Faculty Attitudes And Actions Surrounding Distance Education Accommodations And Inclusiveness Based On Udl Principles, Catherine Cash Jan 2019

Analyzing Faculty Attitudes And Actions Surrounding Distance Education Accommodations And Inclusiveness Based On Udl Principles, Catherine Cash

Electronic Theses and Dissertations

As distance education continues to increase, it is vital that postsecondary institutions contribute time and resources towards upholding inclusive teaching practices that decrease barriers and increase opportunities for diverse student populations. This study examined faculty attitudes and actions surrounding online accommodations and inclusive teaching practices that were based on Universal Design for Learning (UDL) principles using the Inclusive Teaching Strategies Inventory (ITSI), which was adapted into the Inclusive Teaching Strategies Inventory-Distance Education (ITSI-DE) to focus on faculty teaching fully online courses. The ITSI-DE measured the following seven constructs: (a) Accommodations, (b) Accessible Course Materials, (c) Course Modifications, (d) Inclusive Lecture …

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Magnesium-Based Treatment For The Degradation Of Octachlorodibenzofuran And Trinitrotoluene, Amal Mogharbel Jan 2019

Magnesium-Based Treatment For The Degradation Of Octachlorodibenzofuran And Trinitrotoluene, Amal Mogharbel

Electronic Theses and Dissertations

The aim of the present research is to investigate the efficacy of using ball-milled zero-valent magnesium (ZVMg) with and without activated carbon (AC) for the dechlorination of polychlorinated dibenzofurans. Three different solvent systems are presented here which are ethanol, ethanol/ethyl lactate (90:10), and 2-butoxyethanol. These solvents in combination with ZVMg with and without activated carbon were tested towards the degradation of octachlorodibenzofuran (OCDF, the most highly chlorinated PCDF congener). All the tested systems were very powerful and reductively dechlorinated OCDF to less chlorinated congeners. However, the system of ball-milled ZVMg and ethanol was the only system which converted OCDF and …

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Thermo- And Zero-Valent Iron-Activated Persulfate Oxidation Of 3,5,6-Trichloro-2-Pyridinol In An Aquatic System, Roaa Mogharbel Jan 2019

Thermo- And Zero-Valent Iron-Activated Persulfate Oxidation Of 3,5,6-Trichloro-2-Pyridinol In An Aquatic System, Roaa Mogharbel

Electronic Theses and Dissertations

The compound 3,5,6-trichloro-2-pyridinol (TCPy), a metabolite of the broad-spectrum organophosphorous insecticide chlorpyrifos, is both more persistent and more water soluble than its parent compound. This difference, which allows TCPy to more readily leach into surface water and groundwater, has led to widespread contamination of TCPy in soils and aquatic environments. In this study, the degradation of TCPy by sulfate radicals was evaluated using zero valent ironactivated persulfate systems and heat activated persulfate system in aqueous media. Response surface methodology coupled with Box-Behnken design was applied in these studies to evaluate the effects of the independent variables on the mineralization of …

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Improved System For Fabrication And Characterization Of Nanophotonic Devices By Multi-Photon Lithography, Rashi Sharma Jan 2019

Improved System For Fabrication And Characterization Of Nanophotonic Devices By Multi-Photon Lithography, Rashi Sharma

Electronic Theses and Dissertations

A new system for multi-photon lithography (MPL) was developed and used to fabricate three-dimensional (3D) structures with higher aspect ratio, better resolution, improved fidelity, and reduced structural distortion relative to a conventional implementation of MPL. A set of curved waveguides (Rbend = 19 μm, and 38 μm) and straight waveguides (length = 50 μm, Rbend = ∞) were fabricated in an epoxide photopolymer and optically characterized using light having a wavelength in vacuum of λ0 = 2.94 μm. The optical performance of the waveguides was compared to novel spatially-variant photonic crystals (SVPCs) previously studied in the group. The waveguides were …

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