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Origin Of The 610Th Avenue Moraine Of The Des Moines Lobe, Story County, Iowa, Suzanne Marie Ankerstjerne 2010 Iowa State University

Origin Of The 610Th Avenue Moraine Of The Des Moines Lobe, Story County, Iowa, Suzanne Marie Ankerstjerne

Graduate Theses and Dissertations

The late-glacial (<∼>15 kyr B.P.) advance of the soft-bedded Des Moines Lobe, the marginal portion of an ice stream of the Laurentide Ice Sheet, deposited regularly-spaced, transverse moraines. These so-called washboard moraines have relief of 1-5 m, an average spacing of <∼>105 m, and are distributed over the footprint of the Des Moines Lobe. Determining the processes responsible for the formation of these moraines may help illuminate aspects of Des Moines Lobe dynamics and origins of submarine transverse ridges adjacent to modern ice sheets.

Washboard moraines may have formed as a result of weak basal sediments extruding into transverse ...


Stream Bank Soil And Phosphorus Losses Within Grazed Pasture Stream Reaches In The Rathbun Watershed In Southern Iowa, Mustafa Tufekcioglu 2010 Iowa State University

Stream Bank Soil And Phosphorus Losses Within Grazed Pasture Stream Reaches In The Rathbun Watershed In Southern Iowa, Mustafa Tufekcioglu

Graduate Theses and Dissertations

Stream bank erosion within agricultural landscapes is a major pathway for non-point source sediment and phosphorus loading to receiving waters. The objectives of this study were to: 1) compare the effect of livestock stocking rate on sediment and phosphorus loss from stream bank erosion in the Rathbun Watershed in southern Iowa; 2) assess the relationship between stream stage and stream bank soil erosion rates, and 3) evaluate the impacts of current riparian land-uses and stream morphologic characteristics at the field and catchment scale on stream bank erosion. Stream bank erosion rates over three years were estimated using the erosion pin ...


Capture-Based Automated Test Input Generation, Hojun Jaygarl 2010 Iowa State University

Capture-Based Automated Test Input Generation, Hojun Jaygarl

Graduate Theses and Dissertations

Testing object-oriented software is critical because object-oriented languages have been commonly used in developing modern software systems. Many efficient test input generation techniques for object-oriented software have been proposed; however, state-of-the-art algorithms yield very low code coverage (e.g., less than 50%) on large-scale software. Therefore, one important and yet challenging problem is to generate desirable input objects for receivers and arguments that can achieve high code coverage (such as branch coverage) or help reveal bugs. Desirable objects help tests exercise the new parts of the code. However, generating desirable objects has been a significant challenge for automated test input ...


Application Of Fluorescence Spectroscopy: Excited-State Dynamics, Food-Safety, And Disease Diagnosis, Ramkrishna Adhikary 2010 Iowa State University

Application Of Fluorescence Spectroscopy: Excited-State Dynamics, Food-Safety, And Disease Diagnosis, Ramkrishna Adhikary

Graduate Theses and Dissertations

Fluorescence spectroscopy has been widely used in the study of the structure and dynamics of molecules in complex systems. Steady-state and time-resolved fluorescence methods are commonly used to gain insight into the chemical surroundings of the fluorophore. This thesis discusses a range of complex systems and phenomena that may fruitfully be examined by means of fluorescence spectroscopy, in particular: steady-state fluorescence, fluorescence quenching, fluorescence lifetime, time-resolved fluorescence anisotropy, fluorescence resonance energy transfer (FRET), and excited-state solvation dynamics. This thesis focuses on the interactions of fluorophores with biologically and environmentally important macromolecules, hydrogen atom transfer in the excited-state of medicinal pigment ...


Lipid Biomarker Analysis And Stable Carbon Isotope Studies Of Biofilms In The Green Valley Acid Mine Drainage Site, Indiana, U.S.A., Shamik Das Gupta 2010 Iowa State University

Lipid Biomarker Analysis And Stable Carbon Isotope Studies Of Biofilms In The Green Valley Acid Mine Drainage Site, Indiana, U.S.A., Shamik Das Gupta

Graduate Theses and Dissertations

Lipids were extracted in order to explore the microbial communities in eleven biofilms and four layers of two stromatolite samples, from the Green Valley acid mine drainage site in western Indiana. The high concentrations of phytadiene, polyunsaturated fatty acids, phytol, phytanol, and monounsaturated fatty acid 18:1Δ9 in the biofilms indicated the abundance of phototrophs, including microeukaryotes, algae (mainly diatoms), and fungi. Wax esters in the hydrocarbon fraction possibly suggested the presence of localized anaerobic zones within the biofilms, where the microeukaryotes synthesized the esters by an unusual reverse β-oxidation pathway. Other microbial communities in the biofilms mainly included ...


Expanding The Substantial Interactome Of Nemo Using Protein Microarrays., Beau J. Fenner, Michael Scannell, Jochen H M Prehn 2010 Royal College of Surgeons in Ireland

Expanding The Substantial Interactome Of Nemo Using Protein Microarrays., Beau J. Fenner, Michael Scannell, Jochen H M Prehn

Physiology and Medical Physics Articles

Signal transduction by the NF-kappaB pathway is a key regulator of a host of cellular responses to extracellular and intracellular messages. The NEMO adaptor protein lies at the top of this pathway and serves as a molecular conduit, connecting signals transmitted from upstream sensors to the downstream NF-kappaB transcription factor and subsequent gene activation. The position of NEMO within this pathway makes it an attractive target from which to search for new proteins that link NF-kappaB signaling to additional pathways and upstream effectors. In this work, we have used protein microarrays to identify novel NEMO interactors. A total of 112 ...


An Evaluation Of Duck And Ring-Necked Pheasant Nest Survival And Nest Density In Relation To Patch Size And Landscape Variables In Eastern South Dakota, Keith J. Fisk 2010 South Dakota State University

An Evaluation Of Duck And Ring-Necked Pheasant Nest Survival And Nest Density In Relation To Patch Size And Landscape Variables In Eastern South Dakota, Keith J. Fisk

Electronic Theses and Dissertations

Grassland ecosystems in South Dakota have experienced significant transformations over the last 100 years. Landscapes are currently dominated by large agricultural fields interspersed with small, isolated grassland patches. These isolated grassland patches are hypothesized to experience decreased nest survival rates for ring-necked pheasants (Phasianus colchicus) and dabbling duck species due to small size and high degrees of fragmentation. Several natural resource agencies currently conserve grasslands throughout eastern South Dakota, but wildlife managers seek more information on how the size and spatial arrangement of grasslands affect targeted conservation strategies. Therefore, the objectives of this study were to: (1) evaluate the relationship ...


Structural And Functional Study Of Multidrug Transporters, Feng Long 2010 Iowa State University

Structural And Functional Study Of Multidrug Transporters, Feng Long

Graduate Theses and Dissertations

Active efflux of antimicrobial agents is one of the most important strategies that bacteria use to ensure their survival in a toxic extracellular environment. Our interest is to elucidate the structural and functional relationships of bacterial multidrug efflux transporters that give rise to antibiotic resistance. In this dissertation, I focus on studying two specific groups, the multidrug and toxic compound extrusion (MATE) family and the resistance-nodulation-division (RND) family, of multidrug efflux transporters. The functions of the two MATE efflux pumps, NorM of Neisseria gonorrhoeae and YdhE of Escherichia coli, are characterized using a variety of biochemical assays, including drug susceptibility ...


Calculations Of Protein-Protein Interactions With The Fast Multipole Method, Bongkeun Kim 2010 Iowa State University

Calculations Of Protein-Protein Interactions With The Fast Multipole Method, Bongkeun Kim

Graduate Theses and Dissertations

I present a physical model to calculate protein-protein interactions. General formulations to calculate the electrostatic and the van der Waals free energies are brought by the boundary element method of solving linearized Poission-Boltzmann equation in an electrolyte solution, then further expanded to the application of the Fast Multipole Method(FMM). We built an efficient solver to investigate how the mutations on the active site of the protein-protein interface affect changes in binding affinities of protein complexes. Calculated results in addition to the structural analysis help us to understand the protein-protein interaction energy and provide a model to the important applications ...


On Finite-Dimensional Hopf Algebras And Their Classifications, Michael John Hilgemann 2010 Iowa State University

On Finite-Dimensional Hopf Algebras And Their Classifications, Michael John Hilgemann

Graduate Theses and Dissertations

In this thesis, we investigate the classification problem for finite-dimensional Hopf algebras. If p is an odd prime, we show that a non-semisimple Hopf algebra of dimension 2p2 over an algebraically closed field of characteristic zero must be pointed or isomorphic to the dual of a pointed Hopf algebra. Based on previously established classification results, this completes

the classification of Hopf algebras of these dimensions.


Statisical Method And Simulation On Detecting Cracks In Vibrothermography Inspection, Chunwang Gao 2010 Iowa State University

Statisical Method And Simulation On Detecting Cracks In Vibrothermography Inspection, Chunwang Gao

Graduate Theses and Dissertations

Vibrothermography is a nondestructive evaluation method that can be

used to detect cracks in specimens and it is the main engineering

technique we focused in this thesis. This study can be separated into

three parts. In the first part, we develop a systematic statistical

method to provide a detection algorithm to automatically analyze the

data generated in Sonic IR inspections. Principal components analysis

(PCA) was used for dimension reduction. Robust regression and cluster

analysis are used to find the maximum studentized residual (MSD) for

crack detection. The procedure proved to be both more efficient and

more accurate than human inspection ...


Determination Of Saccharides And Ethanol From Biomass Conversion Using Raman Spectroscopy: Effects Of Pretreatment And Enzyme Composition, Chien-ju Shih 2010 Iowa State University

Determination Of Saccharides And Ethanol From Biomass Conversion Using Raman Spectroscopy: Effects Of Pretreatment And Enzyme Composition, Chien-Ju Shih

Graduate Theses and Dissertations

This thesis focuses on developing quantitative spectroscopic methods to determine products from hydrolysis and fermentation reaction. A dispersive Raman spectrometer with 785 nm incident light is used to measure saccharides and ethanol in complex matrices. An appropriate pretreatment step is critical prior to hydrolysis reaction for reducing spectra interference. Different pretreatment methods are compared systematically and the glucose detection limits in hydrolysates are calculated.

Multipeak fitting model is also constructed in order to analyze two main sugars produced from cellulose and hemicellulose. Different ratios of sugar mixtures are used to examine the model's accuracy. Ammonia-pretreated corn stover is hydrolyzed ...


An Xml Based Scalable Implementation Of Temporal Databases Using Parametric Model, Kartic Ramesh 2010 Iowa State University

An Xml Based Scalable Implementation Of Temporal Databases Using Parametric Model, Kartic Ramesh

Graduate Theses and Dissertations

A parametric model and a query language ParaSQL for temporal databases has been proposed in the past. As the attribute values in the model can vary in length, it is difficult to use existing relational storage technology. To address this, CanStoreX, our XML-based storage technology has been deployed in a prior implementation. In parallel, the storage technology as well as our style of implementation for database prototypes have gone through an evolution. This has necessitated the previous implementation to be revisited. In addition, a new parser has been developed using JavaCC. Furthermore, a larger subset of ParaSQL has been implemented ...


Quantitative Aspects Of Vibratory Mobilization And Break-Up Of Non-Wetting Fluids In Porous Media, Wen Deng 2010 Iowa State University

Quantitative Aspects Of Vibratory Mobilization And Break-Up Of Non-Wetting Fluids In Porous Media, Wen Deng

Graduate Theses and Dissertations

Seismic stimulation is a promising technology aimed to mobilize the entrapped non-wetting fluids in the subsurface. The applications include enhanced oil recovery or, alternatively, facilitation of movement of immiscible/partly-miscible gases far into porous media, for example, for CO2 sequestration. This work is devoted to detailed quantitative studies of the two basic pore-scale mechanisms standing behind seismic stimulation: the mobilization of bubbles or drops entrapped in pore constrictions by capillary forces and the break-up of continuous long bubbles or drops.

In typical oil-production operations, oil is produced by the natural reservoir-pressure drive during the primary stage and by artificial water ...


Historical Vegetation Reconstruction Using Spatial Modeling On Pre-Euro-American Data To Inform Ecosystem Restoration In The Driftless Area Of The U.S. Midwest, Kumudan Grubh 2010 Iowa State University

Historical Vegetation Reconstruction Using Spatial Modeling On Pre-Euro-American Data To Inform Ecosystem Restoration In The Driftless Area Of The U.S. Midwest, Kumudan Grubh

Graduate Theses and Dissertations

The potential future outcomes of ecological restoration and management activities can be partially understood by investigating reference conditions and historical processes that contributed to the variability of past ecosystems. Reconstructing pre-Euro-American vegetation from Public Land Survey (PLS) records provides spatially precise and extensive reference information from which such variability estimates can be developed. We thus mapped pre-Euro-American vegetation cover within the Driftless Area of the U.S. Midwest using PLS records. Our mapping employed a four step process. First, trees ambiguously designated by the Public Land surveyors were identified to species using logistic regression models. Next, conditionally specified regression models ...


Identifying And Eliminating Inconsistencies In Mappings Across Hierarchical Ontologies, Bhavesh Sanghvi 2010 Iowa State University

Identifying And Eliminating Inconsistencies In Mappings Across Hierarchical Ontologies, Bhavesh Sanghvi

Graduate Theses and Dissertations

Recent years have seen a rapid proliferation of information sources e.g., on the World-wide Web, in virtually every area of human endeavor. Such autonomous information sources are based on different ontologies, i.e., conceptualizations of the entities, properties, and relationships in the respective domains of discourse. However, practical applications (e.g., building predictive models from disparate data sources, assembling composite web services using components from multiple repositories) call for mechanisms that bridge the semantic gaps between disparate ontologies using mappings that express terms (concepts, properties, and relationships) in a target ontology in terms of those in one or more ...


Analysis Of Variable Vhe Gamma-Ray Emission From The Hard Spectrum Blazar 1es 1218+304, Asif Imran 2010 Iowa State University

Analysis Of Variable Vhe Gamma-Ray Emission From The Hard Spectrum Blazar 1es 1218+304, Asif Imran

Graduate Theses and Dissertations

This thesis is a study of the very high energy gamma-ray emission from the hard spectrum blazar 1ES 1218+304. The data were collected during the 2008/09 observing season by the VERITAS observatory, an array of four atmospheric Cherenkov telescopes in Southern Arizona. This work describes the development of a set of analysis tools suitable for the extraction of the energy spectra of astrophysical objects. Initially, the tools are applied to the Crab nebula data to optimize and calibrate the analysis. Afterwards, the analysis is applied to the high energy observations of the blazar 1ES 1218+304. We report ...


Quark-Gluon Correlation Functions Relevant To Single Transverse Spin Asymmetry, Hong Zhang 2010 Iowa State University

Quark-Gluon Correlation Functions Relevant To Single Transverse Spin Asymmetry, Hong Zhang

Graduate Theses and Dissertations

This thesis presents the evaluation of the relative contributions of various twist-3 quark-gluon correlation functions relevant to single transverse spin asymmetry (SSAs) in a quark-diquark model of the nucleons. The twist-3 quark-gluon correlation functions responsible for gluonic pole and fermionic pole contributions are calculated and compared. We find that at the leading nontrivial order, only gluonic pole contribution is finite and all others are zero for both scalar diquark and axial-vector diquark. We also evalute the symmetries of the these twist-3 quark-gluon correlation functions explicitely


A Novel Principal Component Analysis Method For Identifying Differentially Expressed Gene Signatures, Ai-ling Teh 2010 Iowa State University

A Novel Principal Component Analysis Method For Identifying Differentially Expressed Gene Signatures, Ai-Ling Teh

Graduate Theses and Dissertations

Microarray data sets contain a wealth of information on the gene expression levels for thousands of genes for small number of different conditions called assays. But, the information is hidden by high noise levels, and low signal levels. Data mining techniques are used to extract the information of genes related to the assays. This work proposed a powerful principal component analysis (PCA) based method in extend of PCA approach of Rollins et. al. (2006). The proposed method is able to generate gene signatures that expressed the most differently between two assay groups in a microarray data set.

This work developed ...


An Experimental Study Of Subglacial Clast-Bed Contact Forces, John Louis Byers 2010 Iowa State University

An Experimental Study Of Subglacial Clast-Bed Contact Forces, John Louis Byers

Graduate Theses and Dissertations

The basal ice of sliding glaciers contains rock debris that is held in contact with the rock bed, resulting in abrasion that erodes the bed and friction that slows sliding. Abrasion rates and the magnitude of this friction are controlled by contact forces that clasts exert normal to the bed surface. These contact forces are dependant on the drag exerted on clasts by ice as it flows toward the bed. Recent subglacial measurements indicate that debris-bed friction has been underestimated by at least an order of magnitude. This underestimate may be the result of enhanced drag on particles and associated ...


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