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Retrospective Theses and Dissertations

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Full-Text Articles in Physical Sciences and Mathematics

Mesoporous Silica Nanomaterials And Magnetic Nanoparticles Based Stimuli-Responsive Controlled-Release Delivery Systems, Supratim Giri Jan 2008

Mesoporous Silica Nanomaterials And Magnetic Nanoparticles Based Stimuli-Responsive Controlled-Release Delivery Systems, Supratim Giri

Retrospective Theses and Dissertations

The research presented and discussed within this dissertation involves the development of mesoporous silica nanomaterials and magnetic nanoparticles based stimuli-responsive controlled-release delivery systems.;A superparamagnetic iron oxide nanoparticle-capped, MCM-41 type mesoporous silica nanorod-based controlled-release delivery system (Magnet-MSN) was synthesized. The stimuli-responsive release profiles of fluorescein-loaded Magnet-MSN delivery systems in the presence of external magnetic field was studied by using cell-produced antioxidants as triggers for releasing fluorescein molecules. The intracellular delivery efficiency of the Magnet-MSN system with human cervical cancer cells (HeLa) in vitro was demonstrated involving fluorescein molecules as model drug.;To take the advantage of the intracellular delivery capability ...


Structural Induction: Towards Automatic Ontology Elicitation, Adrian Silvescu Jan 2008

Structural Induction: Towards Automatic Ontology Elicitation, Adrian Silvescu

Retrospective Theses and Dissertations

Induction is the process by which we obtain laws (and more encompassing - theories) about the world. This process can thought as aiming to derive two aspects of a theory: a Structural aspect and a Numerical aspect respectively. The Structural aspect is concerned with the entities modeled and their interrelationship, also known as ontology. The Numerical aspect is concerned with the quantities involved in the relationships among the above-mentioned entities along with uncertainties either postulated to exist in the world or inherent to the nature of the induction process.;In this thesis we will focus more on the structural aspect hence ...


Numerical Computation Of An Optimal Control Problem With Homogenization In One-Dimensional Case, Zhen Li Jan 2008

Numerical Computation Of An Optimal Control Problem With Homogenization In One-Dimensional Case, Zhen Li

Retrospective Theses and Dissertations

We consider an optimal control problem in which the state equation has rapidly oscillating coefficients (characterized by matrix A epsilon, where epsilon is a small parameter). Based on some important results from the paper by S. Kesavan, we convert this optimal control problem to a partial differential equation problem. Therefore, solving optimal control problem is equivalent to solving this partial differential equation problem. By several numerical examples in one dimensional case, we also show that the limit satisfies a problem of the same type but with matrix A 0 (the H-limit of Aepsi).


Beyond The Arithmetic Constraint: Depth-Optimal Mapping Of Logic Chains In Reconfigurable Fabrics, Michael Todd Frederick Jan 2008

Beyond The Arithmetic Constraint: Depth-Optimal Mapping Of Logic Chains In Reconfigurable Fabrics, Michael Todd Frederick

Retrospective Theses and Dissertations

Look-up table based FPGAs have migrated from a niche technology for design prototyping to a valuable end-product component and, in some cases, a replacement for general purpose processors and ASICs alike. One way architects have bridged the performance gap between FPGAs and ASICs is through the inclusion of specialized components such as multipliers, RAM modules, and microcontrollers. Another dedicated structure that has become standard in reconfigurable fabrics is the arithmetic carry chain. Currently, it is only used to map arithmetic operations as identified by HDL macros. For non-arithmetic operations, it is an idle but potentially powerful resource.;Obstacles to using ...


The Evaluation Of Maize Genotypes For Potential Use In Cellulosic Ethanol Production, Krystal Marie Kirkpatrick Jan 2008

The Evaluation Of Maize Genotypes For Potential Use In Cellulosic Ethanol Production, Krystal Marie Kirkpatrick

Retrospective Theses and Dissertations

Corn stover represents a potential lignocellulosic feedstock that may benefit the emerging cellulosic ethanol industry. This study was conducted to determine dry matter yield and quality characteristics of maize stover, cob, and husk plant fractions, and to make predictions of potential ethanol yields. Detergent fiber predictions were made for each plant fraction using near infrared reflectance spectroscopy (NIRS). Predicted values were used to determine ethanol potential using a modified version of the National Renewable Energy Lab (NREL) theoretical ethanol yield calculator. Although significant, not as much variation was present among genotypes and plant fractions for chemical composition as for dry ...


The Effects Of Farmer Attitudes And Farm Management Practices On Soil Quality: A Study In Cherokee County, Iowa, Amber D. Anderson Mba Jan 2008

The Effects Of Farmer Attitudes And Farm Management Practices On Soil Quality: A Study In Cherokee County, Iowa, Amber D. Anderson Mba

Retrospective Theses and Dissertations

This study seeks to relate farmer attitudes, perceptions, and management characteristics to field soil quality and laboratory fertility indicators. Farmer interviews were conducted to document recent practices on the farm as well as farmer attitudes about farming. To obtain soil quality measures, both the Natural Resource Conservation Service's field soil quality kit and laboratory tests were employed. Sites from the eastern half of Cherokee County, Iowa, were selected.;Key considerations of this study included farmer practices of renting versus owning land and organic or synthetic nitrogen application. Additional farmer data, including attitudes about farming, are used in this analysis ...


Implementing The Science Writing Heuristic Laboratory Report Format In The Undergraduate Organic Chemistry Laboratory, Jacob Daniel Schroeder Jan 2008

Implementing The Science Writing Heuristic Laboratory Report Format In The Undergraduate Organic Chemistry Laboratory, Jacob Daniel Schroeder

Retrospective Theses and Dissertations

This dissertation describes how a traditional organic chemistry laboratory was reformed into a guided inquiry laboratory. Data presented illustrate the lack of correlation between the traditional laboratory and the corresponding lecture. After reforming the laboratory, student scores on lecture exams increased, specifically on exam questions directly related to concepts introduced in the laboratory. This dissertation covers work completed over the course of four years and includes the new laboratory manual, instructor notes for each new experiment, as well as a laboratory practical exam.


The Impact Of Upper-Level Flow Regime Change From Spring To Summer On Qpf Accuracy Over The Midwest, Mark R. Loeffelbein Jan 2008

The Impact Of Upper-Level Flow Regime Change From Spring To Summer On Qpf Accuracy Over The Midwest, Mark R. Loeffelbein

Retrospective Theses and Dissertations

Quantitative precipitation forecasts (QPF) are potentially the most significant challenge of weather forecasting, and have been historically difficult for numerical weather prediction (NWP) models to produce. Given the importance of QPF to weather forecasts, there is a need to improve its accuracy. Understanding and recognizing patterns prone to produce errors in model QPF can help predictions made by weather forecasters.;The low level jet (LLJ) observed over the Great Plains is responsible for supporting warm-season convection by transporting heat and moisture into the Midwest. This study examines the two types of dominant mid and upper-level flow patterns during the warm-season ...


Impacts Of Mass Media Coverage Of The Economy During Normal Times And Recessions On The Index Of Consumer Confidence Using Time Series Analysis And Granger Causal Analysis, Lishan Su Jan 2008

Impacts Of Mass Media Coverage Of The Economy During Normal Times And Recessions On The Index Of Consumer Confidence Using Time Series Analysis And Granger Causal Analysis, Lishan Su

Retrospective Theses and Dissertations

The level of consumer sentiment influences decision making of policy makers, and therefore it is important to examine if media have powerful impacts on consumer sentiment. Based on the theories of business cycles and second-level agenda-setting, this study applies Granger causal analysis and time series analysis to explore the causal relationships among economic reporting by media, consumer sentiment and the real state of the economy embodied in Business Week, the Index of Consumer Confidence (CCI) and the Standard & Poor's 500 (S&P 500). The results indicate that interpretation by media have only limited effects on the level of consumer ...


The Geochemistry Of Carbonate-Hosted Pb-Zn-Ag Mineralization In The Lavrion District, Attica, Greece: Fluid Inclusion, Stable Isotope, And Rare Earth Element Studies, Todd Andrew Bonsall Jan 2008

The Geochemistry Of Carbonate-Hosted Pb-Zn-Ag Mineralization In The Lavrion District, Attica, Greece: Fluid Inclusion, Stable Isotope, And Rare Earth Element Studies, Todd Andrew Bonsall

Retrospective Theses and Dissertations

Carbonate-replacement Pb-Zn-Ag deposits in the Lavrion district, Greece, are spatially related to a 7 to 10 Ma granodiorite intrusion and various sills and dikes of mafic to acid composition. The Plaka granodiorite contains porphyry molybdenite mineralization and is spatially associated with a Cu-Fe skarn. Carbonate-replacement deposits occur predominantly in marbles (Upper and Lower marble of the Basal Unit), Kaesariani schists, and along a major detachment fault. Orebodies are mainly manto-style, but mineralization also occurs in veins. The mineralogy of carbonate-replacement deposits is dominated by base metal sulfides and sulfosalts of Ag, Bi, Sn, Sb, As, and Pb, particularly at Plaka ...


Fault Slip Velocities Inferred From The Spectra Of Ground Motion, Nergis Ani Anil-Bayrak Jan 2008

Fault Slip Velocities Inferred From The Spectra Of Ground Motion, Nergis Ani Anil-Bayrak

Retrospective Theses and Dissertations

Better understanding of earthquake-source properties is an important goal in seismology. Dynamic fault theories and practices of ground-motion prediction need independent information about source characteristics obtained directly from recorded data.;The maximum slip velocity on a rupturing fault is the parameter that controls the strength of an earthquake's high-frequency radiation and the properties of its Fourier spectra. We therefore have tested an empirical method for determining the peak slip velocities for a number of well-recorded earthquakes using such spectral information.;High-quality ground-motion data from small-to-moderate earthquakes in Japan were collected, and Fourier transforms of the accelerograms were computed for ...


Global Behavior Of Graph Dynamics With Applications To Markov Chains, Jose Ayala-Hoffmann Jan 2008

Global Behavior Of Graph Dynamics With Applications To Markov Chains, Jose Ayala-Hoffmann

Retrospective Theses and Dissertations

No abstract provided.


Practical Tools For Exploring Data And Models, Hadley Alexander Wickham Jan 2008

Practical Tools For Exploring Data And Models, Hadley Alexander Wickham

Retrospective Theses and Dissertations

No abstract provided.


Development In Electrophoresis: Instrumentation For Two-Dimensional Gel Electrophoresis Of Protein Separation And Application Of Capillary Electrophoresis In Micro-Bioanalysis, Aoshuang Xu Jan 2008

Development In Electrophoresis: Instrumentation For Two-Dimensional Gel Electrophoresis Of Protein Separation And Application Of Capillary Electrophoresis In Micro-Bioanalysis, Aoshuang Xu

Retrospective Theses and Dissertations

No abstract provided.


Inverse Scattering Problems For First-Order Systems, Jaemin Shin Jan 2008

Inverse Scattering Problems For First-Order Systems, Jaemin Shin

Retrospective Theses and Dissertations

In this thesis, the Zakharov-Shabat scattering problem and several types of Landau-Lifschitz scattering problems are considered. The inverse scattering problem is that of seeking one or more coefficients in a system of diffierential equation from the scattering data which, generally, consists of a reflection coefficient and bound state data.;We assume mainly that the coefficients to be determined are of half line support, i.e. they are equal to zero on a half line. Such cases can arise on natural physical grounds, and they can be very good approximations in case of reasonably rapid decay.;Assuming that the coefficients have ...


Nitrous Oxide And Methane Fluxes In Riparian Buffers And Adjacent Crop Fields, Dong-Gill Kim Jan 2008

Nitrous Oxide And Methane Fluxes In Riparian Buffers And Adjacent Crop Fields, Dong-Gill Kim

Retrospective Theses and Dissertations

Denitrification is recognized as the major mechanism for reducing nitrate (NO3-) in riparian buffers and thus diminishing non-point source pollution (NPS) of surface water bodies subject to high N loads. However, increasing denitrification rates in riparian buffers may be trading the problem of NPS pollution of surface waters for atmospheric deterioration and increased global warming potential because denitrification produces nitrous oxide (N2O), a greenhouse gas also involved in stratospheric ozone depletion. Also N2O produced in the denitrification process can be dissolved in groundwater and is eventually emitted into the air when groundwater flows into a stream or a river. Riparian ...


Spatial Ability Cognitive Model With Act-R 6.0, Andre Lokasari Jan 2008

Spatial Ability Cognitive Model With Act-R 6.0, Andre Lokasari

Retrospective Theses and Dissertations

The effectiveness of software interface design is a lot of the times tied to the user of the software. In particular, it is tied to how users comprehend the spatial stimuli presented to them through the software interface (spatial information encoding). Thus, the goal of the research is to understand the aspects of different levels of spatial ability on a spatial software interface for creating a theoretical structure of spatial ability on a simple task as a stepping stone to understand a more complex demanding task. Why is this important? The importance of knowing the different spatial ability aspect relates ...


Identification, Evaluation And Quantification Of Vocs As Biosecure Markers Of Swine Carcass Degradation, Neslihan Akdeniz Jan 2008

Identification, Evaluation And Quantification Of Vocs As Biosecure Markers Of Swine Carcass Degradation, Neslihan Akdeniz

Retrospective Theses and Dissertations

Swine carcasses were composted using passively-aerated composting system designed by the Canadian Food Inspection Agency during the 2004 Avian influenza outbreak in British Columbia. In this system, swine carcasses were fully covered by plastic sheets due to biosecurity concerns and visual inspection of the swine carcasses was impossible. Monitoring volatile organic compounds (VOCs) released from carcasses was a promising approach to assess progress and completion of the carcass degradation. In this study, VOCs were sampled using solid phase microextraction (SPME). Samples were analyzed using multidimensional gas chromatography-mass spectrometry (MDGC-MS) (a) to develop a comprehensive chemical library of volatile organic compounds ...


Integrating Qtl Analysis Into Plant Breeding Practice Using Bayesian Statistics, Shengqiang Zhong Jan 2008

Integrating Qtl Analysis Into Plant Breeding Practice Using Bayesian Statistics, Shengqiang Zhong

Retrospective Theses and Dissertations

Plant breeders face the challenges to incorporate significant developments in Bayesian quantitative trait locus (QTL) analysis into breeding practice. The overall objective of this dissertation is to integrate QTL analysis into marker-assisted selection (MAS) in plant breeding using Bayesian statistics. Three different perspectives were studied: identification of optimal designs to generate multiple families for QTL mapping, cross prediction using QTL analysis results, and genomic selection for cultivated barley. First, the impact of two mating designs was studied on QTL mapping in multiple families generated by crosses between multiple inbred lines, using within-family linkage disequilibrium (LD) with a Bayesian variable selection ...


Development And Application Of A Hybrid Femtosecond/Picosecond Coherent Raman Probe Designed For Study Of Excited State Systems, Benjamin Douglas Prince Jan 2008

Development And Application Of A Hybrid Femtosecond/Picosecond Coherent Raman Probe Designed For Study Of Excited State Systems, Benjamin Douglas Prince

Retrospective Theses and Dissertations

The conversion from purely femtosecond coherent anti-Stokes Raman spectroscopy (CARS) to a more advantageous hybrid femtosecond/picosecond CARS (fs/ps CARS) probe for time-resolved vibrational dynamics studies is detailed. This probe provides a number of benefits for the use of studying the evolution of electronically excited states, including rapid data acquisition speeds, increased spectral resolution, and discrimination against competing background signals. The high time resolution is shown to depend on the cross correlation of the excitation pulse and initial CARS pulses while the high frequency resolution is shown to depend on the final CARS electric field. The pump-fs/ps CARS ...


Determination Of Nad+ And Nadh Level In A Single Cell Under H2o2 Stress By Capillary Electrophoresis, Wenjun Xie Jan 2008

Determination Of Nad+ And Nadh Level In A Single Cell Under H2o2 Stress By Capillary Electrophoresis, Wenjun Xie

Retrospective Theses and Dissertations

A capillary electrophoresis (CE) method is developed to determine both NAD+ and NADH levels in a single cell, based on an enzymatic cycling reaction. The detection limit can reach down to 0.2 amol NAD + and 1 amol NADH on a home-made CE-LIF setup. The method showed good reproducibility and specificity. After an intact cell was injected into the inlet of a capillary and lysed using a Tesla coil, intracellular NAD + and NADH were separated, incubated with the cycling buffer, and quantified by the amount of fluorescent product generated. NADH and NAD + levels of single cells of three cell lines ...


Influences Of Midtropospheric Perturbations On Summer Convective Storms Over The United States Northern Plains, Shih-Yu Wang Jan 2008

Influences Of Midtropospheric Perturbations On Summer Convective Storms Over The United States Northern Plains, Shih-Yu Wang

Retrospective Theses and Dissertations

No abstract provided.


Inductively Coupled Plasma: Fundamental Particle Investigations With Laser Ablation And Applications In Magnetic Sector Mass Spectrometry, Nathan Joe Saetveit Jan 2008

Inductively Coupled Plasma: Fundamental Particle Investigations With Laser Ablation And Applications In Magnetic Sector Mass Spectrometry, Nathan Joe Saetveit

Retrospective Theses and Dissertations

Particle size effects and elemental fractionation in laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) are investigated with nanosecond and femtosecond laser ablation, differential mobility analysis, and magnetic sector ICP-MS. Laser pulse width was found to have a significant influence on the LA particle size distribution and the elemental composition of the aerosol and thus fractionation. Emission from individual particles from solution nebulization, glass, and a pressed powder pellet are observed with high speed digital photography. The presence of intact particles in an ICP is shown to be a likely source of fractionation. A technique for the online detection of ...


Ethnic-Identity Intensity As A Moderator Of The Technology Acceptance Model And Its Antecedents, Marcus Anthony Alexander Jan 2008

Ethnic-Identity Intensity As A Moderator Of The Technology Acceptance Model And Its Antecedents, Marcus Anthony Alexander

Retrospective Theses and Dissertations

The goal of this dissertation is oriented to study the motivation of minorities to adopt and learn new, innovative technologies. The primary research question: is there some reason the African-American experience is driving certain sub-groups of the population to the wrong side of the digital divide? To examine this, I introduce ethnic identity as a moderating variable to a leftward extended technology acceptance model (TAM). Additionally, both components of the classic TAM (ease of use and usefulness) are divided into two antecedents: (1) ease of use - (a) trait efficacy and (b) state efficacy and (2) usefulness (completely replaced by) - (a ...


Interannual And Intraseasonal Variations Of The Energy Budget Over The Polar Regions And Its Climatic Implications, Wan-Ru Huang Jan 2008

Interannual And Intraseasonal Variations Of The Energy Budget Over The Polar Regions And Its Climatic Implications, Wan-Ru Huang

Retrospective Theses and Dissertations

The atmospheric energy budget is often adopted by previous studies to explore the balance between energy sources/sinks and the divergence of atmospheric energy flux. Because the atmospheric circulation is essentially generated by the energy balance between sources and sinks, a better knowledge of an energy budget will lead to a better understanding of the atmospheric circulation and its variations.;Climatologically, the polar regions are the major sink regions of global energy. The energy in the polar regions undergoes interannual and 30-60 day variations. It was inferred from previous studies dealing with the poleward propagation of angular momentum that energy ...


Lc-Ms Analysis Of Related Peptides And Anions In The Positive Mode, Renee Joy Hein Jan 2008

Lc-Ms Analysis Of Related Peptides And Anions In The Positive Mode, Renee Joy Hein

Retrospective Theses and Dissertations

This dissertation focuses on the use of LC-MS for the analysis of related peptides and anions in the positive mode. Separating closely related peptides (those differing by one or two amino acids or the chirality of a single amino acid) can be challenging using reversed-phase liquid chromatography (LC), ion exchange LC, or using ion-pairing agents. Also, the mobile phases that give the best separations in these modes may not be electrospray ionization mass spectrometry (ESI-MS) compatible. Macrocyclic glycopeptide stationary phases were investigated as an alternative to the standard C18 stationary phase for the separation of related peptides. On the macrocyclic ...


An Online System For Bioterrorism Surveillance, Melissa Yahya Jan 2008

An Online System For Bioterrorism Surveillance, Melissa Yahya

Retrospective Theses and Dissertations

Bioterrorism has become one of the greatest threats for nations. As bioterrorism threats are increasing these days, research in bioterrorism surveillance has been conducted to detect the threats at the earliest time. Following this research, some bioterrorism surveillance systems have been developed. Some of these systems use humans as indicators and the others use animals. Both of these systems detect the threats by collecting and analyzing the statistical data on health trends. Since most bio-weapons start as animal diseases, using animals as indicators allow identification of a bioterrorism threat at earlier time than using humans.;Current bioterrorism surveillance systems based ...


Cooking Up Quantum Chemistry, Bosiljka Njegic Jan 2008

Cooking Up Quantum Chemistry, Bosiljka Njegic

Retrospective Theses and Dissertations

Accurate vibrational frequencies were calculated using the vibrational self-consistent field method (VSCF). The effect of anharmonicity of calculated frequencies on thermodynamic properties, such as entropy, was explored. The developments of the VSCF method were introduced in the manner in which potential energy surface (PES) is being generated. The comparison of harmonic, scaled harmonic and anharmonic frequencies, was made. Furthermore, the computing of a PES within the VSCF method was coarse-grain parallelized in order to enable calculations on bigger molecules. Finally, the work conducted on the reaction mechanism of the industrially important process of production of H2O2 catalyzed by gold nanoparticles ...


Photometric Variability Of Sun-Like Stars In The Old Open Cluster M67, Ryan Wesley Tobin Jan 2008

Photometric Variability Of Sun-Like Stars In The Old Open Cluster M67, Ryan Wesley Tobin

Retrospective Theses and Dissertations

Few physical processes can affect the earth's climate on a global scale. The variability of the Sun is one such process. The Sun is known to vary by about 0.1% due to Sunspots and other surface activity. We do not yet know whether the Sun's variability is normal. Using the well-known properties of the old open cluster M67, we look for variations in Sun-like stars.;In this thesis, we present the results of observation, calibration, correction and analysis of stars in M67. We focus on Sun-like stars and binary systems. We also determine the limits of observation ...


A Specification Language Design For The Java Modeling Language (Jml) Using Java 5 Annotations, Kristina Boysen Taylor Jan 2008

A Specification Language Design For The Java Modeling Language (Jml) Using Java 5 Annotations, Kristina Boysen Taylor

Retrospective Theses and Dissertations

Design by contract specification languages help programmers write their intentions for a piece of code in a formal mathematical language. Most programming languages do not have built-in syntax for such specifications, so many design by contract languages place specifications in comments. The Java Modeling Language (JML) is one such specification language for Java that uses comments to specify contracts. However, starting with version 5, Java has introduced annotations, a syntactical structure to place metadata in various places in the code. This thesis proposes an initial design to writing JML contracts in the Java 5 annotation syntax and evaluates several criteria ...