Physical Sciences and Mathematics Commons^™

Optical Modeling Of Schematic Eyes And The Ophthalmic Applications, Bo Tan

Doctoral Dissertations

The objectives of this dissertation are to advance and broaden the traditional average eye modeling technique by two extensions: 1) population-based and personalized eye modeling for both normal and diseased conditions, and 2) demonstration of applications of this pioneering eye modeling.The first type of representative eye modeling can be established using traditional eye modeling techniques with statistical biometric information of the targeted population. Ocular biometry parameters can be mathematically assigned according to the distribution functions and correlations between parameters. For example, the axial dimension of the eye relates to age, gender, and body height factors. With the investigation results from …

Multiscale Modeling Of The Electronic, Optical, And Magnetic Properties Of Low-Dimensional Metal Systems, Ke Zhao

Doctoral Dissertations

This thesis presents a study of the electronic, optical and magnetic properties of low-dimensional metal systems across multiple scales, using a variety of theoretical techniques including microscopic phenomenological model, ab initio density functional theory (DFT) and classical electromagnetics.

In the study of the interaction between a molecule and metal substrate, a new mechanism of the chemical enhancement for surface-enhanced Raman scattering (SERS) was discovered. Through a microscopic phenomenological model, it has been demonstrated that 102-104 chemical enhancement may originate from the coupling between an electric field parallel to the surface of a metal substrate and the perpendicular vibration mode of …

Search For Electron Antineutrinos From The Sun With Kamland Detector, Oleg Victorovic Perevozchikov

Doctoral Dissertations

In this dissertation I present the results of the search for the electron antineutrinos from the Sun with Kamioka Liquid scintillator Anti-Neutrino Detector (KamLAND). There is no known direct production of the electron antineutrinos in the Sun. However, in the some theoretical models with the large neutrino magnetic moment antineutrinos from the Sun can be produced e.g. via Spin Flavor Precession mechanism (SFP). Search for solar antineutrinos potentially can provide new information about fundamental properties of neutrinos. The most sensitive one-kiloton antineutrino detector KamLAND gives the possibility to search for such antineutrinos.

The analysis described in this dissertation is based …

Assembling The Blue Ridge And Inner Piedmont: Insights Into The Nature And Timing Of Terrane Accretion In The Southern Appalachian Orogen From Geologic Mapping, Stratigraphy, Kinematic Analysis, Petrology, Geochemistry, And Modern Geochronology, Arthur James Merschat

Doctoral Dissertations

Detailed geologic mapping, SHRIMP U-Pb zircon geochronology, geochemistry, petrology, and structural and kinematic analyses were applied to decipher the structure, tectonic heredity, and Paleozoic accretionary history of suspect terranes of the southern Appalachian Blue Ridge (BR) and Inner Piedmont (IP). Detailed geologic mapping in the Waynesville and Sam Knob 7.5-minute quadrangles recognized the Great Balsam Mountains window cored by sillimanite I and II zone Dahlonega gold belt rocks, overthrust by migmatitic biotite gneiss of the Cartoogechaye terrane to the northwest, and migmatitic Tallulah Falls Formation of the Tugaloo terrane to the southeast. Suspect terranes of the BR and IP consist …

Spectroscopic Imaging For The Detection And Identification Of Bacterial Contaminations, Michael Gilbert

Doctoral Dissertations

There exist many types of harmful bacteria that can contaminate foods and cause serious illness, which often have their own best courses of treatment. This requires the classification of different types of bacteria. Traditional methods of bacterial identification, while able to provide accurate classification, are often very time-consuming processes. In the case of a potentially fatal bacterial infection, time is often of the essence. FTIR spectroscopy is a faster, more practical alternative that can discriminate different strains of bacteria, based on their spectral signatures, with high confidence.

Bacterial contaminations on food exist as small, localized colonies that must be found …

Adaptive Discontinuous Galerkin Finite Element Methods, Haihang You

Doctoral Dissertations

The Discontinuous Galerkin Method is one variant of the Finite Element Methods for solving partial differential equations, which was first introduced by Reed and Hill in 1970’s [27]. Discontinuous GalerkinMethod (DGFEM) differs from the standard Galerkin FEMthat continuity constraints are not imposed on the inter-element boundaries. It results in a solution which is composed of totally piecewise discontinuous functions. The absence of continuity constraints on the inter-element boundaries implies that DG method has a great deal of flexibility at the cost of increasing the number of degrees of freedom. This flexibility is the source of many but not all of …

W229-Interpreting Mehlich 1 And 3 Soil Test Extractant Results For P And K In Tennessee, The University Of Tennessee Agricultural Extension Service

Field & Commercial Crops

The Mehlich 1 and 3 soil test extractants are the most widely used in laboratories of the southern United States today. Tennessee began using the Mehlich 1 extractant in December, 1981. Existing soil test calibration data in Tennessee are based on the Mehlich 1 soil test extractant,1,2 which became available in 1953.

Studies On A Polarized Proton Target For Reactions With Radioactive Ion Beams, Juan Pablo Urrego-Blanco

Doctoral Dissertations

Over the last few years, much progress has been made towards the understanding of basic properties of nuclei with extreme neutron to proton ratios. However, the study of phenomena involving spin polarized nuclei near the drip lines remains practically unexplored. The importance of such studies lies in the fact that the most complete knowledge of the scattering matrix is obtained in reactions with polarized particles. The purpose of this dissertation was to explore the feasibility of using polarized probes in reactions with exotic nuclei. We identified areas where reactions between Radioactive Ion Beams (RIBs) and light polarized targets open a …

Geometrical Effects On Electromagnetic Enhancement To Sers From Metal Nanoparticle Dimer Arrays, Abigail Laurel Gaddis

Masters Theses

Much recent effort has been devoted to the study of the optical properties of metal nanoparticle substrates. In such finely ordered structures, surface plasmons can be induced by incident light. These collective excitations of the electrons in the nanoparticle create localized areas of high electromagnetic field intensity. The intense local fields generated are of interest for various applications, including Surface-enhanced Raman Scattering (SERS) for molecular detection and sensing. In this thesis, the optical properties of various nanoparticle dimer and array geometries are considered, including gold triangular prism dimers and silver spherical dimers. The effect of SERS due to electromagnetic interaction …

High-Sensitivity Spectral Fluorescence Lifetime Imaging For Resolving Spectroscopically Overlapping Species, Justin Lee Crawford

Masters Theses

The capability to resolve the contributions from spectroscopically overlapping fluorophores has enabled significant breakthroughs in cellular imaging. However, commercial microscopes for this purpose use analog light detection with least squares curve-fitting analysis and improvements in sensitivity are needed. To this end, a microscope has been constructed with high throughput and single-photon detection capability. The fluorescence is separated through use of a prism spectrometer or a series of dichroic mirrors into four spectral bands and detected using four single-photon avalanche diode (SPAD) detectors, which provide high-quantum efficiency in the red spectral region. The detectors are connected to a time-correlated single photon …

Elemental Analysis Of Soils Using Laser-Induced Breakdown Spectroscopy (Libs), Ningfang Yang

Masters Theses

Laser-induced breakdown spectroscopy (LIBS) has been applied for the quantitative analysis of various samples, but it is controversial for chemically-complex soils. In order to study the effect of delay time, gate width, and repetition rate on the LIBS signal in soil, the emission line at 396.84 nanometer was selected. The results indicated that repetition rate, delay time, and gate width significantly affected the LIBS signal, delay time was more important than gate width in controlling the LIBS signal. The optimum instrumental parameters for soil analysis were obtained when repetition rate, delay time, and gate width equaled 10 hertz, 1 microsecond, …

Optimal Control Applied To Population And Disease Models, Rachael Lynn Miller Neilan

Doctoral Dissertations

This dissertation considers the use of optimal control theory in population models for the purpose of characterizing strategies of control which minimize an invasive or infected population with the least cost. Three different models and optimal control problems are presented. Each model describes population dynamics via a system of differential equations and includes the effects of one or more control methods.

The first model is a system of two ordinary differential equations describing dynamics between a native population and an invasive population. Population growth terms are functions of the control, constructed so that the value of the control may affect …

Countable Groups As Fundamental Groups Of Compacta In Four-Dimensional Euclidean Space, Ziga Virk

Doctoral Dissertations

This dissertation addresses the question of realization of countable groups as funda- mental groups of continuum. In first chapter we discuss classical realizations in the category of CW complexes. We introduce Eilenberg-Maclane spaces and their topological properties. The second chapter provides recent developments on realization question such as those of Shelah, Keesling, ... The third chapter proves the realization theorem for countable groups. The re- sulting space is compact path connected, connected subspace of four dimensional Euclidean space.

Small And Large Scale Limits Of Multifractal Stochastic Processes With Applications, Jennifer Laurie Sinclair

Doctoral Dissertations

Various classes of multifractal processes, that is processes that display different properties at different scales, are studied. Most of the processes examined in this work exhibit stable trends at small scales and Gaussian trends at large scales, although the opposite can also occur. Many natural phenomena exhibit a fractal structure depending on some scaling factor, such as space or time. Thus, these types of processes have many useful modeling applications, including Biology and Economics. First, generalized tempered stable processes are defined and studied, following the original work on tempered stable processes by Jan Rosinski [16]. Generalized tempered stable processes encompass …

Two-Step Variations For Processes Driven By Fractional Brownian Motion With Application In Testing For Jumps From The High Frequency Data, Shiying Si

Doctoral Dissertations

In this dissertation we introduce the realized two-step variation of stochastic processes and develop its asymptotic theory for processes based on fractional Brownian motion and on more general Gaussian processes with stationary increments. The realized two-step variation is analogous to the realized 1, 1-order bipower variation introduced by Barndorff-Nielsen and Shephard [8] but mathematically is simpler to deal with. The powerful techniques of Wiener/Itˆo/Malliavin calculus for establishing limit laws play a key rule in our proofs. We include some stochastic simulations as an illustration of our theory. As a result of our study, we provide test statistics for testing for …

An Automated Approach To The Study And Classification Of Colliding And Interacting Galaxies, Steven Alvaro Boada

Masters Theses

Colliding galaxies are perhaps the greatest events changing and evolving our Universe. Consequently, the need for an understanding of how that interaction originated is very important. This thesis presents a framework in which the study of these events can be conducted in a timely and efficient manner. A genetic algorithm coupled with an initial conditions generator, a physics engine and an analysis package performs an automated search to visually match an unknown galactic interaction with a known event, thus providing the starting conditions that created such an interaction.

Fluorescence Characterization Of Karst Aquifers In East Tennessee, Teresa L. Brown

Masters Theses

Karst and fractured rock aquifers are primary sources of drinking water in the Appalachian region, even though most are inherently susceptible to surface-derived contamination. Many of the obstacles to water supply protection in such systems could be alleviated through the use of tracer testing to delineate recharge areas and surface-to-groundwater connections. Tracer testing is currently under-utilized, however, due to public safety concerns and ambivalence on the part of regulatory agencies. This study aimed to address this issue through a characterization of the fluorescent properties of typical carbonate aquifers for the purpose of refining the timing and design of low-concentration dye …

Microfluidic Device For The Electrokinetic Manipulation Of Single Molecules, Jason Keith King

Masters Theses

Manipulation and trapping of single molecules in solution is a useful tool for studies of biological molecules and molecular dynamics, but has to date been implemented in only one or two dimensions. The goal of the research in this thesis is to develop a microfluidic device to address the need for three-dimensional manipulation of single fluorescent molecules in solution. The device consists of two pairs of platinum electrodes deposited onto two standard borosilicate glass coverslips via ultraviolet microlithography and ionic sputtering. The two coverslips are sandwiched together such that the electrode tips form a tetrahedral configuration, and by applying appropriate, …

Single Molecule Detection Of Near-Infrared Phthalocyanine Dyes, You Li

Masters Theses

The major advantage associated with near-infrared monitoring is the fact that few compounds show intrinsic fluorescence in this region of the spectrum and hence background from other molecules is reduced. Phthalocyanine dyes provide emission at deep red and near infrared wavelengths but have excellent photostability and hence are an attractive candidate for near-infrared fluorescence bioassay applications. However, because of their small Stokes shifts, non-standard methods are needed for optimum separation of fluorescence from scattered laser light. This thesis reports the development of a custom confocal microscope that uses a lowcost laser diode operating at 667 nm for sample excitation and …

Some Congruence Modulo 2 Statements Of Primitive Conway Vassiliev Invariants., James M. Dawson

Masters Theses

Polynomial knot invariants can often be used to define Vassiliev invariants on singu- lar knots. Here Vassiliev invariants form the Conway, Jones, HOMFLY, and Kauffman polynomials are explored. Also, some explanation is given about how symbols of the Jones and Conway polynomial can evaluated on suitable chord diagrams. These in- variants are further used to find expressions that are congruent modulo 2 to some low degree invariants derived from the Primitive Conway polynomial.

Application Of The Explicit Asymptotic Method To Nuclear Burning In Type Ia Supernova, Christopher Ryan Smith

Masters Theses

Modern problems in astrophysics tend to require large, complex computational frameworks to solve many aspects of the system simultaneusly. Calculation of the energy production through nuclear reactions is typically one of those aspects. The use of standard nuclear burning algorithms will take up the majority of the computational time with all but the smallest of networks. The explicit asymptotic method has shown promise in computing large networks faster than existing methods in various environments while retaining accuracy. The purpose of this thesis is to show that this method can be successfully used to solve complex systems using a network of …

High Energy Particle Physics At The University Of Tennessee, Stefan M Spanier

Physics and Astronomy Publications and Other Works

Talk given at the Governor's school in 2009. It is an introduction to particle physics.

Novel Approach To Ocular Photoscreening, Kevin Charles Baker

Doctoral Dissertations

Photoscreening is a technique that is typically applied in mass pediatric vision screening due to advantage of its objective, binocular, and cost-effective nature. Through the retinal reflex image, ocular alignment and refractive status are evaluated. In the USA, this method has screened millions of preschool children in the past years. Nevertheless, the efficiency of the screening has been contentious. In this dissertation, the technique is reviewed and reexamined. Revisions of photoscreening technique are developed to detect and quantify strabismus, refractive errors, and high-order ocular aberrations. These new optical designs overcome traditional design deficiencies in three areas:

First, a Dynamic Hirschberg …

Cross Sections Spring 2009, Department Of Physics And Astronomy

Cross Sections

No abstract provided.

A Trip To The Beginning Of The Universe With The Large Hadron Collider, Stefan M Spanier

Physics and Astronomy Publications and Other Works

Slides from a presentation given at the Science Forum of the University of Tennessee. It discusses the physics program of the Large Hadron Collider in general terms. Serves as introductory material to the field.

Utk Geography Newsletter 9 (2008-2009), Department Of Geography

UTK Geography Newsletter

No abstract provided.

Identifying The Source Of Unknown Microcystin Genes And Predicting Microcystin Variants By Comparing Genes Within Uncultured Cyanobacterial Cells, C.J. Allender, G.R. Lecleir, J.M. Rinta-Kanto, R.L. Small, M.F. Satchwell, G.L. Boyer, Steven Wilhelm

Microbiology Publications and Other Works

While multiple phylogenetic markers have been used in the culture independent study of microcystin producing cyanobacteria, in only a few instances have multiple markers been studied within individual cells, and in all cases these studies have been conducted with cultured isolates. Here, we isolate and evaluate large DNA fragments (> 6 kb) encompassing two genes involved in microcystin biosynthesis (mcyA2 and mcyB1) and use them to identify the source of gene fragments found in water samples. Further investigation of these gene loci from individual cyanobacterial cells allowed for improved analysis of the genetic diversity within microcystin producers as …

Actinorhodopsin Genes Discovered Diverse In Freshwater Habitats And Among Cultivated Actinobacteria, A.K. Sharma, K. Sommerfeld, G.S. Bullerjahn, A.R. Matteson, Steven Wilhelm, J. Jezbera, U. Brandt, W.F. Doolittle, M.W. Hahn

Microbiology Publications and Other Works

Microbial rhodopsins are membrane proteins that utilize a retinal chromophore to harvest sunlight for energetic and photosensory functions. Recently, a group of novel rhodopsin sequences named ‘actinorhodopsins’ (ActRs) was hypothesized to exist among uncultured planktonic Actinobacteria. ActRs were discovered by mining metagenomic data obtained during the Venter Institute’s Global Ocean Sampling expedition, from a hypersaline lagoon, two estuaries and a freshwater lake. On the basis of these findings, and many studies that show Actinobacteria are common inhabitants of lakes, we predicted that ActR genes would likely be present in other freshwater habitats and among the genomes of cultivated Actinobacteria …

The Effects Of Increased Pco2 And Temperature On The North Atlantic Spring Bloom: I. The Phytoplankton Community And Biogeochemical Response, Y. Feng, C.E. Hare, K. Leblanc, J.M. Rose, Y Zhang, G.R. Ditullio, P. Lee, Steven Wilhelm, J.M. Rowe, J. Sun, N. Nemcek, C. Gueguen, U. Passow, I. Benner, C. Brown, D.A. Hutchins

Microbiology Publications and Other Works

ABSTRACT: The North Atlantic spring bloom is one of the largest annual biological events in the ocean, and is characterized by dominance transitions from siliceous (diatoms) to calcareous (coccolithophores) algal groups. To study the effects of future global change on these phytoplankton and the biogeochemical cycles they mediate, a shipboard continuous culture experiment (Ecostat) was conducted in June 2005 during this transition period. Four treatments were examined: (1) 12°C and 390 ppm CO₂ (ambient control), (2) 12°C and 690 ppm CO₂ (high pCO₂), (3) 16°C and 390 ppm CO₂ (high temperature), and (4) 16°C and …

Effects Of Increased Pco2 And Temperature On The North Atlantic Spring Bloom: Iii. Dimethylsulfoniopropionate, P.A. Lee, J.R. Rudisill, A.R. Neeley, D.A. Hutchins, Y. Feng, C.E. Hare, K. Leblanc, J.M. Rose, Steven Wilhelm, J.M. Rowe, G.R. Ditullio

Microbiology Publications and Other Works

The CLAW hypothesis argues that a negative feedback mechanism involving phytoplankton-derived dimethylsulfoniopropionate (DMSP) could mitigate increasing sea surface temperatures that result from global warming. DMSP is converted to the climatically active dimethylsulfide (DMS), which is transferred to the atmosphere and photochemically oxidized to sulfate aerosols, leading to increases in planetary albedo and cooling of the Earth’s atmosphere. A shipboard incubation experiment was conducted to investigate the effects of increased temperature and pCO2 on the algal community structure of the North Atlantic spring bloom and their subsequent impact on particulate and dissolved DMSP concentrations (DMSP_p and DMSP_d). Under …