Physical Sciences and Mathematics Commons^™

Understanding The Activity Of Model Catalyst Surfaces: Ultrahigh Vacuum And Atmospheric Pressure Studies, Kangmin Xie

Theses and Dissertations

Heterogeneous Catalysis plays an extremely important role in the world. Metal particles supported on oxide supports are the most widely employed heterogeneous catalysts. In order to provide insight into the development of new catalytic materials, a fundamental understanding of surface reactions is required. Vapor-deposited metal clusters on single-crystal surfaces are well-defined systems that can be used to understand the structure-relationships in commercial catalysts. The pressure gap between fundamental surface analysis under ultra-high vacuum (UHV, P~10-10 Torr) conditions and kinetic evaluation of catalysts under realistic pressures has been bridged by constructing a micro-reactor interfaced with UHV chamber: pre- and post-reaction surfaces …

Surface Chemistry And Transport Properties Of Ii-Vi Semiconductor Nanowires, Pravin Paudel

Theses and Dissertations

Semiconductor nanowires have been widely studied due to their unique properties such as width comparable to critical length-scales, high aspect ratio, and high carrier mobility. These unique properties make them a suitable candidate for various optical and electronic devices like photovoltaics, photodetectors, and field effect transistors. The nanowire surface plays an important role in the performance of these devices because of their high surface to volume ratio. The larger surface area of nanowires may provide better charge separation than planar heterostructures in photovoltaics by providing shorter distance to move for carrier before separation, however, presence of surface states may lead …

Binary Quartic Forms Over Fp, Daniel Thomas Kamenetsky

Theses and Dissertations

Let Vp denote the five dimensional vector space of binary quartic forms over the finite field Fp, with p a prime greater than 3. There is a natural action of the group GL1(Fp)×GL2(Fp) on Vp. This action partitions Vp into orbits, the number of which increases with p. In this thesis, we determine explicitly, for a given p, the number of orbits under the action of GL1(Fp) × GL2(Fp) on Vp. Moreover, we determine the size of each orbit and the general structure of the forms each orbit contains. We also introduce an application of understanding these orbits to the …

Measurement Of New Observables From The Π + Π - Electroproduction Off The Proton, Arjun Trivedi

Theses and Dissertations

Knowledge of the Universe as constructed by human beings, in order to tackle its complexity, can be thought to be organized at varying scales at which it is observed. Implicit in such an approach is the idea of a smooth evolution of knowledge between scales and, therefore, access to how Nature constructs the visible Universe beginning from its most fundamental constituents. New and, in a sense, fundamental phenomena may typically be emergent as the scale of observation changes. The study of the Strong Interaction, which is responsible for the construction of the bulk of the visible matter in the Universe …

Forensic Characterization Of Dyes From Synthetic Textile Fibers Exposed To Outdoor And Laundering Effects By Ultra Performance Liquid Chromatography And Spectral Analysis, Molly Rebecca Burnip

Theses and Dissertations

Textile fibers found in an investigation are trace evidence that can connect a suspect to a victim or crime scene. Examination involves comparison of the color and morphology of a questioned fiber to a known fiber with optical spectroscopy. Fibers are considered class evidence, so evaluating more characteristics increases their significance as evidence if a match cannot be excluded. Acrylic, nylon, and polyester are textile polymers that require different extraction solvents based on the polymer chemistry. Methods have been developed for UPLC analysis of basic dyes on acrylic, acid on nylon, and disperse dyes on polyester. After microextraction from single …

Semiparametric Regression Analysis Of Panel Count Data And Interval-Censored Failure Time Data, Bin Yao

Theses and Dissertations

This dissertation discusses three important research topics on semiparametric regression analysis of panel count data and interval-censored data. Both types of data arise commonly in real-life studies in many fields such as epidemiology, social science, and medical research. In these studies, subjects are usually examined multiple times at periodical or irregular follow-up examinations. For panel count data, the response variable is the counts of some recurrent events, whose exact occurrence times are usually unknown. For interval-censored data, the response variable is the time to some events of interest, often called survival time or failure time, and the exact response time …

Frailty Probit Models For Clustered Interval-Censored Failure Time Data, Haifeng Wu

Theses and Dissertations

Survival analysis is an important branch of statistics that deals with time to event data or survival data. An important feature of such data is that the survival time of interest is usually not completely known but is censored due to the design of the study or an early dropout. In this dissertation we focus on studying clustered interval-censored data, a special type of survival data. Interval-censored data arise in many epidemiological, social science, and medical studies, in which subjects are examined at periodical follow-up visits. The survival (or failure) time of interest is never exactly observed but is known …

Neuro-Fuzzy Classification Of Felsic Lava Geomorphology At Alarcon Rise, Mexico, Christina Hefron Maschmeyer

Theses and Dissertations

The Alarcon Rise is the only submarine oceanic spreading ridge setting where rhyolitic lavas have been found. This intermediate-rate spreading ridge provides a unique natural laboratory for studying the geomorphology of felsic submarine lava flows at oceanic spreading ridges. Seafloor observations of felsic lava indicate the flow morphology differs from typical submarine basaltic lava at the few other oceanic spreading ridges where differentiated compositions have been recorded. Morphologic variation between mafic and felsic lava flows, especially rhyolites, was also observed at Alarcon Rise.

The Monterey Bay Aquarium Research Institute conducted mapping surveys with autonomous underwater vehicle D Allan B. in …

Computational Doping For Fuel Cell Material Design Based On Genetic Algorithms And Genetic Programming, Emrah Atilgan

Theses and Dissertations

Developing new materials have historically been time-consuming. Computational material discovery can search large design space to identify promising candidates for experimental verification. Recently, Density Functional Theory (DFT) based first principle calculation has been able to calculate many electrical and physical properties of materials, making them suitable for computational doping based material discovery. In material doping, given a base material, one can change its properties by substituting some elements with new ones or adding additional elements. In computational doping, we have a grid of atoms in a supercell, some of which can be substituted with dopant atoms. There are many possible …

Learning Human Poses From Monocular Images, Xiaochuan Fan

Theses and Dissertations

In this research, we mainly focus on the problem of estimating the 2D human pose from a monocular image and reconstructing the 3D human pose based on the 2D human pose. Here a 3D pose is the locations of the human joints in the 3D space and a 2D pose is the projection of a 3D pose on an image. Unlike many previous works that explicitly use hand-crafted physiological models, both our 2D pose estimation and 3D pose reconstruction approaches implicitly learn the structure of human body from human pose data.

This 3D pose reconstruction is an ill-posed problem without …

Uptake Of Nanoparticles By Vibrio Gazogenes, Shonda Renee Jones

Theses and Dissertations

Vibrio gazogenes, a Gram-negative species of marine bacteria, was capable of transporting 20 nm (diameter) surface-carboxylated, polystyrene, fluorescent FluoSpheres® microspheres (excitation/emission = 505/515) through the outer membrane, which was indicated by a detectable decrease in the fluorescence intensity of the nanoparticles in the culture medium. A mechanism of transport was investigated involving the ATP-binding cassette (ABC) protein transporters that traverse the outer membrane. Inhibition of the ABC transporters did not prevent the entry of the nanoparticles into the cell, suggesting there was an alternate mechanism of transport. The addition of nanoparticles to the culture medium also did not provide any …

Development Of Protein-Polymer Core-Shell Nanoparticles (Ppcs-Nps) As Efficient Vehicles To Deliver Therapeutic Agents Across Blood Brain Barrier (Bbb), Napat Tandikul

Theses and Dissertations

Blood Brain Barrier (BBB) plays a main role as selective barrier which controls and limits access of chemicals, molecules and therapeutic agents from blood to brain. The BBB endothelial cells are connected by Tight Junctions (TJs) which close intracellular spaces between the endothelial cells and block the free diffusion of substances, therefore many potential drugs for treating human brain diseases cannot reach the brain in sufficient concentration. Recently, many studies have thrown an interest in development of nanoparticles for delivering drugs and imaging agents across BBB. Our research group has developed protein-polymer core-shell nanoparticles (PPCS-NPs) which demonstrate great potential for …

The Reflected-Shifted-Truncated-Gamma Distribution For Negatively Skewed Survival Data With Application To Pediatric Nephrotic Syndrome, Sophia D. Waymyers

Theses and Dissertations

Negatively skewed survival data arise occasionally in public health fields and in statistical research. Standard distributions such as the exponential, generalized F, generalized gamma, Gompertz, log-logistic, lognormal, Rayleigh, and Weibull distributions are not always well suited to this data. The primary goal of this dissertation is to find a viable alternative for modeling negatively skewed survival data such as the time to first remission for pediatric patients with frequently relapsing or steroid dependent nephrotic syndrome.

We begin with a brief introduction of survival analysis and the nature of pediatric nephrotic syndrome. A meta-analysis on atopy and pediatric nephrotic syndrome using …

Properties And Applications Of Self-Assembled Benzophenone Bis-Urea Macrocycles, Arthur Ariston Korous

Theses and Dissertations

Supramolecular chemistry is a vast multidisciplinary field with great potential and application. It is driven by one simple concept, the self-assembly of small building blocks into larger complex architectures without application of external force. This thesis highlights previous applications of supramolecular chemistry in addition to new potential properties and applications. Recently, the Shimizu group reported a self-assembled benzophenone bis-urea macrocycle (host 1) that facilitated the selective oxidation of an encapsulated alkene when UV-irradiated in an oxygen atmosphere to afford products that are typically observed in radical mediated reactions.1 Surprisingly, the host displayed a stable room temperature radical upon UV irradiation. …

From Model Systems To Real Catalysts: Bridging The Pressure And Materials Gaps, Audrey S. Duke

Theses and Dissertations

For decades a fundamental understanding of heterogeneous catalysts has been pursued for rational catalyst design using model systems under ultrahigh vacuum (UHV) conditions; however, there exist stark differences between the simplified models investigated under UHV and the industrial catalysts used at high pressures. To bridge these gaps, it becomes essential to utilize progressively more complex materials and to correlate their surface structure and activity using incrementally higher pressure techniques. In this work, both model Pt-Re catalysts and powdered metal-organic frameworks (MOFs) were studied using a suite of traditional UHV surface science techniques in addition to ambient pressure X-ray photoelectron spectroscopy …

Classification Of Natural Phytoplankton Populations With Fluorescence Excitation-Based Imaging Multivariate Optical Computing, Shawna Kathleen Tazik

Theses and Dissertations

Phytoplankton account for the majority of the primary productivity in the ocean and contribute significantly to the global carbon cycle through photosynthesis. A quantitative characterization of phytoplankton cell size and taxonomic composition is essential for understanding marine biogeochemical cycles, quantifying carbon export, and for predicting the ocean’s response to future climate change. Our labs have developed a new instrument for this purpose that combines fluorescence excitation spectroscopy with an all-optical approach to multivariate statistics called multivariate optical computing (MOC). The instrument, known as the Shipboard Streak Imaging Multivariate Optical Computing (SSIMOC) photometer, is a simple filter photometer that images the …

Virus Particles Provide Nanotopographical Cues For Osteogenic Differentiation Of Mesenchymal Stem Cells, Kamolrat Metavarayuth

Theses and Dissertations

One key aspect of tissue engineering is to develop biomimetic scaffolding materials that can modulate the proliferation, self-renewal and differentiation of multipotent stem cells into different lineages. Bone marrow derived mesenchymal stem cells (BMSCs) can differentiate into several target cells such as osteoblasts, chondrocytes, adipocytes, and smooth muscle cells. BMSCs are commonly used for in vitro osteogenesis studies in bone tissue engineering field. However the mechanisms and signaling pathways that these cells use to recognize and response to biomaterial surface are still unclear. This dissertation focuses on investigating the effect of chemical and physical cues introduced by virus nanoparticles on …

Investigating Structure-Activity Relationships Of Sl11 To Develop A Better Prostate Cancer Diagnostic, Rong Huang

Theses and Dissertations

Prostate cancer is now the second leading cause of cancer death in American men. Since many of the diagnostics either have high false results or risky, it’s important to have better diagnostics and earlier diagnosis of prostate cancer. Aberrant glycosylation is a hallmark of cancer. When cancer occurs, aberrant glycosylation occurs, therefore, glycosylation patterns may provide information about different cancer types and metastatic potential. In order to study and use these glycosylation patterns, the boronic acid functionalized synthetic lectins that can interact with glycans have been developed. The work described here focuses on 1) the structure activities of synthetic lectins …

Structure Of The Stable Marriage And Stable Roommate Problems And Applications, Joe Hidakatsu

Theses and Dissertations

The well-known Gale-Shapley algorithm is a solution to the stable marriage problem, but always results in the same stable marriage, regardless of how the algorithm is executed. Robert Irving and Paul Leather constructed the rotation poset, whose downward closed sets are in one-to-one correspondence with the set of stable marriage assignments. We discuss how to use the rotation poset to find the k-optimal matching, and prove that a k-optimal matching is the same as a minimum regret matching for high enough k. Finally, Dan Gusfield defines the rotation poset for the stable roommate problem, and uses it to efficiently enumerate …

Modeling Of Structural Relaxation By A Variable-Order Fractional Differential Equation, Su Yang

Theses and Dissertations

In physical point of view, relaxation usually describes the return from a perturbed system into equilibrium and each process has its own characteristic relaxation time. In 1946, Tool first formulated the notion of fictive temperature to characterize the structure of a glass-forming melt. Since then, people used to simulate structural relaxation by first order model. Since fractional-based models have not widely applied in modeling the fictive temperature, I want to explore the the possibility of modeling structural relaxation by fractional differential equation.

In this thesis, I will first introduce the definitions of two different kinds of fractional derivatives: Riemann-Liouville fractional …

On A Constant Associated With The Prouhet-Tarry-Escott Problem, Maria E. Markovich

Theses and Dissertations

For n a positive integer, the Prouhet-Tarry-Escott Problem asks for two different sets of n positive integers for which the sum of the kth powers of the elements of one set is equal to the sum of the kth powers of the elements of the second set for each positive integer k < n. For n > 12, it is not known whether such sets exist. I will give some background on this problem and then show how Newton polygons can be used to determine information on the size of the 2-adic value of a certain constant associated with the problem.

Improved Systems For On-Site Raman Measurements, William Joshua Huntington

Theses and Dissertations

The need to development lightweight miniature sensors for spectrometers for use in hazardous environments such as war zones, industrial settings, and space exploration is ever growing. This thesis will present studies aimed at improving Raman instruments for such applications by reducing the size, weight, and power consumption of the instrument. The two methods described here include the utilization of a light emitting diode (LED) source for Raman spectroscopy and a new type of Raman gas sensor.

Chapter one describes a new Raman spectrometer that utilizes an LED for Raman excitation coupled to the SHRS. LEDs are highly divergent broadband , …

Alongshore Momentum Balance Over Shoreface-Connected Ridges, Fire Island, Ny, Conor Ofsthun

Theses and Dissertations

Bathymetric variations, such as shoreface-connected ridges (SFCRs), modify inner shelf circulation, altering the significance of and relationships between alongshore momentum balance terms. The inner shelf of Fire Island, NY provides a study site representative of SFCRs around the world. During the winter of 2014, hydrodynamic observations (~12 m depth) from 6 ADCPs, 3 SeaGauge pressure sensors, 2 tide gauges, and 2 meteorological buoys were collected over a region of the inner shelf spanning a full wavelength of one such SFCR. Analysis of the data, under westward wind forcing, revealed a predominantly alongshore circulation with localized offshore (onshore) current veering over …

Sample Size Calculation For Ph Mixture Cure Model, Yihong Zhan

Theses and Dissertations

With the development of advanced medical technology, a significant proportion of patients can be cured of many chronic diseases. Because a substantial fraction of patients have censored information, the standard survival model, such as the proportional hazards (PH) model cannot capture the cured information of patients. Thus PH mixture cure model is developed to handle the survival data with potential cured information. A corresponding sample size formula based on log rank test has been proposed by Wang et al. (2012) and the probability of death in their formula is only contributed by the control arm. However, to calculate the sample …

Registration And Clustering Of Functional Observations, Zizhen Wu

Theses and Dissertations

As an important exploratory analysis, curves of similar shape are often classified into groups, which we call clustering of functional data. Phase variations or time distortions are often encountered in the biological processes, such as growth patterns or gene profiles. As a result of time distortion, curves of similar shape may not be aligned. Regular clustering methods for functional data usually ignore the presence of phase variations, which may result in low clustering accuracy. However, it is difficult to account for phase variation without knowing the cluster structure.

In this dissertation, we first propose a Bayesian method that simultaneously clusters …

Applications Of Disposable Pipette Technologies With Lc-Ms/Ms For Forensic And Clinical Analyses Of Biological Matrices, Kaylee R. Mastrianni

Theses and Dissertations

Efficiently hydrolyzing glucuronide metabolites is an important step in the analysis of drugs in urine. Amitriptyline and cyclobenzaprine are both tricyclic compounds with tertiary aliphatic amine groups that are subsequently metabolized to a less common form of glucuronide metabolite, quaternary ammonium linked glucuronides (N+- glucuronide). A collaborative study was conducted to investigate discrepancies in recoveries of these two commonly prescribed compounds in patient urine samples when hydrolyzed with different enzyme from four different commercially available β-glucuronidase sources.

Similarly, there is potential for 6-monoacetylmorphine to be converted to morphine during β-glucuronidase hydrolysis of urine samples. 6-monoacetylmorphine is a unique metabolite of …

Regular Expression Synthesis For Blast Two-Hit Filtering, Jordan Bradshaw

Theses and Dissertations

Genomic databases are exhibiting a growth rate that is outpacing Moore's Law, which has made database search algorithms a popular application for use on emerging processor technologies. NCBI BLAST is the standard tool for performing searches against these databases, which operates by transforming each database query into a filter that is subsequently applied to the database. This requires a database scan for every query, fundamentally limiting its performance by I/O bandwidth. In this dissertation we present a functionally-equivalent variation on the NCBI BLAST algorithm that maps more suitably to an FPGA implementation. This variation of the algorithm attempts to reduce …

Ligand Engineering For Advanced Functional Composite Materials, Michael H. Bell

Theses and Dissertations

The surface modification of solid inorganic substrates for thermodynamic compatibility with organic polymer media has become an important area of study for the development of advanced functional composite materials. Polymer ligands covalently bound to the substrate surface have been an effective means to achieve said compatibility. Current investigations focus on multifunctional ligand engineering where multiple chemically distinct species, each with specific functionality, can be implemented on the filler surface simultaneously. A combination of matrix compatible polymer brushes and conjugated charge trapping moieties attached to filler surfaces are investigated for enhancements in dielectric properties. Presented herein are the synthesis and characterization …

Modern Estimation Problems In Group Testing, Md Shamim Sarker

Theses and Dissertations

In the simplest form of group testing, pools are formed by compositing a fixed number of individual specimens (e.g., blood, urine, swab, etc.) and then the pools are tested for a binary characteristic, such as presence or absence of a disease. Group testing is commonly used to screen for a variety of sexually transmitted diseases in epidemiological applications where the main goal is to increase testing efficiency. In this dissertation, we study three estimation problems that are motivated by real-life applications. We propose new methods to model group testing data for both single and multiple infections. In the first problem, …

Efficient Partitioning And Allocation Of Data For Workflow Compositions, Annamaria Victoria Kish

Theses and Dissertations

Our aim is to provide efficient partitioning and allocation of data for web service compositions. Web service compositions are represented as partial order database transactions. We accommodate a variety of transaction types, such as read-only and write-oriented transactions, to support workloads in cloud environments. We introduce an approach that partitions and allocates small units of data, called micropartitions, to multiple database nodes. Each database node stores only the data needed to support a specific workload. Transactions are routed directly to the appropriate data nodes. Our approach guarantees serializability and efficient execution.

In Phase 1, we cluster transactions based on data …