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Functional Materials From Hierarchically Ordered Polymer Nanocomposites, Brandon Josef Franck 2011 Iowa State University

Functional Materials From Hierarchically Ordered Polymer Nanocomposites, Brandon Josef Franck

Graduate Theses and Dissertations

We report work done studying the segregation of polymer coated gold nanoparticles within block copolymer (BCP) composites. Poly(styrene-b-isoprene) (PI-b-PS) of Mn 172 kDa was loaded with various particle fractions of gold nanoparticle with various surface chemistries. Segregation of the particles within the BCP composite was examined via electron microscopy. "Single component" nanocomposites with BCP ligands of PI-b-PS and poly(isoprene-b-dimethylsiloxane) "grafted to" gold nanoparticles were introduced and a study of ordering was done via electron microscopy and small-angle x-ray scattering.


Purification Of Flavan-3-Ol Biosynthesis For Co-Localization Onto Nanocarriers And A Multi-Enzyme Assay, Emily Kaitlin Davenport 2011 Iowa State University

Purification Of Flavan-3-Ol Biosynthesis For Co-Localization Onto Nanocarriers And A Multi-Enzyme Assay, Emily Kaitlin Davenport

Graduate Theses and Dissertations

Flavonoids are polyphenolic secondary metabolites that serve a variety of purposes, from assisting pollination in plants to providing anti-cancerous activity in humans. It is the wide range of functions that give these molecules the highly revered status they have today. Range in function can be linked with the range in structure, and with over 10,000 different flavonoids known, they make up one of the largest groups of natural products. One common sub-class of flavonoids is the flavan-3-ols, which are known for their health benefits and tendency to condense to form proanthocyanidins, or condensed tannins. Both of these classes of ...


Comparison Of Subsurface And Surface Runoff Phosphorus Transport Rates In Alluvial Floodplains, Aaron R. Mittelstet, Derek M. Heeren, Garey A. Fox, Daniel E. Storm, Michael J. White, Ronald B. Miller 2011 Oklahoma State University, Stillwater

Comparison Of Subsurface And Surface Runoff Phosphorus Transport Rates In Alluvial Floodplains, Aaron R. Mittelstet, Derek M. Heeren, Garey A. Fox, Daniel E. Storm, Michael J. White, Ronald B. Miller

Biological Systems Engineering: Papers and Publications

Phosphorus (P) loading to streams can occur by both surface runoff and subsurface transport, with subsurface P transport often assumed negligible. Groundwater P concentrations in alluvial aquifers can be significant, especially in preferential flow paths (PFPs). The objectives of this research were to quantify subsurface P transport rates at two sites in northeastern Oklahoma and to compare them with surface runoff P transport rates derived from a hydrologic model, the Pasture Phosphorus Management Calculator (PPM Plus). Ozark ecoregion study sites were adjacent to the Barren Fork Creek and Honey Creek in northeastern OK, USA. Each site, instrumented with 24 observation ...


Corn Seed Spacing Uniformity As Affected By Seed Tube Condition, Michael F. Kocher, John M. Coleman, John A. Smith, Stephen D. Kachman 2011 University of Nebraska-Lincoln

Corn Seed Spacing Uniformity As Affected By Seed Tube Condition, Michael F. Kocher, John M. Coleman, John A. Smith, Stephen D. Kachman

Biological Systems Engineering: Papers and Publications

Variation in corn seed spacing from a John Deere MaxEmergeTM Plus Vacumeter planter was evaluated on the University of Nebraska Planter Test Stand in a laboratory setting for two seed tube conditions (new or worn) with two examples of corn seed shape (round or flat). Seed spacing uniformity was measured using three seed spacing uniformity parameters: Coefficient of Precision (CP3), ISO Multiples index, and ISO Miss index.

Differences were detected in all three seed spacing uniformity parameters due to the seed tube condition. The new seed tubes had better seed spacing uniformity than the worn seed tubes, within each ...


Completely Biodegradable Soyprotein–Jute Biocomposites Developed Using Water Without Any Chemicals As Plasticizer, Narendra Reddy, Yiqi Yang 2011 University of Nebraska-Lincoln

Completely Biodegradable Soyprotein–Jute Biocomposites Developed Using Water Without Any Chemicals As Plasticizer, Narendra Reddy, Yiqi Yang

Biological Systems Engineering: Papers and Publications

Soyprotein–jute fiber composites developed using water without any chemicals as the plasticizer show much better flexural and tensile properties than polypropylene–jute composites. Co-products of soybean processing such as soy oil, soyprotein concentrate and soy protein isolates are inexpensive, abundantly available and are renewable resources that have been extensively studied as potential matrix materials to develop biodegradable composites. However, previous attempts on developing soy-based composites have either chemically modified the co-products or used plasticizers such as glycerol. Chemical modifications make the composites expensive and less environmentally friendly and plasticizers decrease the properties of the composites. In this research, soyprotein ...


Evaluation Of Soil Salinity Leaching Requirement Guidelines, John Letey, Glenn J. Hoffman, Jan W. Hopmans, Stephen R. Grattan, Donald Louis Suarez, Dennis L. Corwin, Jim D. Oster, Laosheng Wu, Christopher Amrhein 2011 University of California, Riverside,

Evaluation Of Soil Salinity Leaching Requirement Guidelines, John Letey, Glenn J. Hoffman, Jan W. Hopmans, Stephen R. Grattan, Donald Louis Suarez, Dennis L. Corwin, Jim D. Oster, Laosheng Wu, Christopher Amrhein

Biological Systems Engineering: Papers and Publications

Water for irrigation is a major limitation to agricultural production in many parts of the world. Use of waters with elevated levels of salinity is one likely option to meet the supply of increased demands. The sources of these waters include drainage water generated by irrigated agriculture, municipal wastewater, and poor quality groundwater. Soil salinity leaching requirements that were established several decades ago were based on steady-state conditions. Recently transient-state models have been developed that potentially can more correctly predict the dynamics of the chemical–physical–biological interactions in an agricultural system. The University of California Center for Water Resources ...


Ethanol Yields And Cell Wall Properties In Divergently Bred Switchgrass Genotypes, Gautam Sarath, Bruce S. Dien, Aaron J. Saathoff, Kenneth P. Vogel, Robert B. Mitchell, Han Chen 2011 USDA Central-East Regional Biomass Center, Lincoln, NE

Ethanol Yields And Cell Wall Properties In Divergently Bred Switchgrass Genotypes, Gautam Sarath, Bruce S. Dien, Aaron J. Saathoff, Kenneth P. Vogel, Robert B. Mitchell, Han Chen

Biological Systems Engineering: Papers and Publications

Genetic modification of herbaceous plant cell walls to increase biofuels yields is a primary bioenergy research goal. Using two switchgrass populations developed by divergent breeding for ruminant digestibility, the contributions of several wall-related factors to ethanol yields was evaluated. Field grown low lignin plants significantly out yielded high lignin plants for conversion to ethanol by 39.1% and extraction of xylans by 12%. However, across all plants analyzed, greater than 50% of the variation in ethanol yields was attributable to changes in tissue and cell wall architecture, and responses of stem biomass to diluteacid pretreatment. Although lignin levels were lower ...


Metabolic Flux Analysis Of Escherichia Coli Mg1655 Under Octanoic Acid (C8) Stress, Yanfen Fu 2011 Iowa State University

Metabolic Flux Analysis Of Escherichia Coli Mg1655 Under Octanoic Acid (C8) Stress, Yanfen Fu

Graduate Theses and Dissertations

Metabolic engineering has evolved to the point of fulfilling the dream of having industrial chemicals produced renewably. Carboxylic acids [e.g., short chain fatty acids (SCFAs) such as octanoic acid (C8)] are such chemical intermediates that can be produced by Escherichia coli engineered with thioesterases specific for short chain fatty acids. However, C8 is toxic to E. coli at concentration greater than 10 mM. To design a better host strain for the production of large amount of SCFAs, 13C metabolic flux analysis of E. coli was performed for both C8 stress and control condition (without C8). To investigate central carbon ...


Surface Functionalization Of Quantum Dots For Biotechnological Applications, Yanjie Zhang 2011 Iowa State University

Surface Functionalization Of Quantum Dots For Biotechnological Applications, Yanjie Zhang

Graduate Theses and Dissertations

Quantum dots (QDs) are considered as fantastic substitutes for organic dyes or genetically coded proteins because of their outstanding optical properties including broad absorption spectra, size tunable emission spectra, large extinction coefficient and superior resistance to chemical and physical degradation. They are now widely used in many biological applications. However, QDs are generally synthesized using organometallic approach and only soluble in organic solvents. To transfer QDs into aqueous solution, we replaced their native ligands with a new group of water-soluble molecules based on simple yet flexible dithiocarbamate chemistry. This cap exchange method offers QDs not only solubility but also stability ...


Multiscale Modeling For Complex Macromolecular Systems: Methodologies And Applications, Seung Ha Kim 2011 Iowa State University

Multiscale Modeling For Complex Macromolecular Systems: Methodologies And Applications, Seung Ha Kim

Graduate Theses and Dissertations

The objective of this dissertation is to understand the binding mechanism between flexible macromolecules and guest species in solution using multiscale molecular modeling strategies, including: ab initio electronic structure theory, all-atom classical molecular dynamics simulations, coarse-grained molecular dynamics simulations, and statistical eld theory. A brief summary of the subsequent chapters in this thesis is provided. Chapters 2 - 7 and Appendix A are self-contained units complete with literature review and bibliography.


High Throughput Design Of Functionalized Nanoparticles For Targeted Vaccine Delivery, Ana Vianey Chavez-santoscoy 2011 Iowa State University

High Throughput Design Of Functionalized Nanoparticles For Targeted Vaccine Delivery, Ana Vianey Chavez-Santoscoy

Graduate Theses and Dissertations

This dissertation focuses on the design of functionalized nanoparticles, a novel approach to targeted antigen delivery by decorating the surface of polyanhydride nanoparticles with specific carbohydrates to provide "pathogen-like" properties.

Polyanhydride nanoparticles are promising vaccine platforms that have the potential to be used as controlled drug delivery devices as well as potent and effective immune adjuvants for the design of single dose vaccines. CLRs offer unique advantages for tailoring immune responses. Engagement of CLRs regulates antigen presenting cell activation and promotes delivery of antigens to specific intracellular compartments inside antigen presenting cells for efficient processing and presentation.

CLRs recognize conserved ...


Hybrid Thermochemical Processing: Fermentation Of Pyrolysis-Derived Bio-Oil, Laura R. Jarboe, Zhiyou Wen, Dong Won Choi, Robert C. Brown 2011 Iowa State University

Hybrid Thermochemical Processing: Fermentation Of Pyrolysis-Derived Bio-Oil, Laura R. Jarboe, Zhiyou Wen, Dong Won Choi, Robert C. Brown

Chemical and Biological Engineering Publications

Thermochemical processing of biomass by fast pyrolysis provides a nonenzymatic route for depolymerization of biomass into sugars that can be used for the biological production of fuels and chemicals. Fermentative utilization of this bio-oil faces two formidable challenges. First is the fact that most bio-oil-associated sugars are present in the anhydrous form. Metabolic engineering has enabled utilization of the main anhydrosugar, levoglucosan, in workhorse biocatalysts. The second challenge is the fact that bio-oil is rich in microbial inhibitors. Collection of bio-oil in distinct fractions, detoxification of bio-oil prior to fermentation, and increased robustness of the biocatalyst have all proven effective ...


Engineering Ethanologenic Escherichia Coli For Levoglucosan Utilization, Donovan S. Layton, Avanthi Ajjarapu, Dong Won Choi, Laura R. Jarboe 2011 Iowa State University

Engineering Ethanologenic Escherichia Coli For Levoglucosan Utilization, Donovan S. Layton, Avanthi Ajjarapu, Dong Won Choi, Laura R. Jarboe

Chemical and Biological Engineering Publications

Levoglucosan is a major product of biomass pyrolysis. While this pyrolyzed biomass, also known as bio-oil, contains sugars that are an attractive fermentation substrate, commonly-used biocatalysts, such as Escherichia coli, lack the ability to metabolize this anhydrosugar. It has previously been shown that recombinant expression of the levoglucosan kinase enzyme enables use of levoglucosan as carbon and energy source. Here, ethanologenic E. coli KO11 was engineered for levoglucosan utilization by recombinant expression of levoglucosan kinase from Lipomyces starkeyi. Our engineering strategy uses a codon-optimized gene that has been chromosomally integrated within the pyruvate to ethanol (PET) operon and does not ...


Analysis Of The Performance Of Peanut Fame In A Single Cylinder Idi Engine And Investigations Of Neat Methyl Ester Influence On Fuel Quality, Jeffery Lewis 2011 Georgia Southern University

Analysis Of The Performance Of Peanut Fame In A Single Cylinder Idi Engine And Investigations Of Neat Methyl Ester Influence On Fuel Quality, Jeffery Lewis

Electronic Theses and Dissertations

Author's abstract: To meet evolving standards set forth by the U.S. EPA and U.S. Energy Policy it is necessary to consider a variety of feedstock for biofuels synthesis and to understand the role individual fatty acids contribute to the overall performance. It is the belief of the authors that excess peanut production would provide an excellent source for high quality biodiesel feedstock, and the complete property and combustion analysis of the fatty acid components will provide insight for future biofuel developments. The preliminary investigations of the project focused on the combustion performance and thermal efficiency of peanut ...


Modeling Heat Transfer During Cooling Of Ready-To-Eat Meat And Poultry Products Using Three-Dimensional Finite Element Analysis And Web-Based Simulation, Jihan F. Cepeda Jimenez 2010 University of Nebraska-Lincoln

Modeling Heat Transfer During Cooling Of Ready-To-Eat Meat And Poultry Products Using Three-Dimensional Finite Element Analysis And Web-Based Simulation, Jihan F. Cepeda Jimenez

Biological Systems Engineering--Dissertations, Theses, and Student Research

The meat industry is required to comply with processing performance standards for preventing the growth of foodborne pathogens in products. These performance standards, established by the United States Department of Agriculture - Food Safety and Inspection Service (USDA-FSIS) require a reduction of Salmonella spp (lethality standard) and limit the growth of sporeforming bacteria (stabilization standard) in certain processed meat products. In general, strategies used to comply with these standards are associated with thermal processing. Meat processors have difficulties complying with these performance standards. Moreover, thermal processing deviations are an issue in the meat industry that generate uncertainty regarding the safety of ...


Development Of An Integrated Soil Properties Mapping System, Rajveer S. Dhillon 2010 University of Nebraska - Lincoln

Development Of An Integrated Soil Properties Mapping System, Rajveer S. Dhillon

Biological Systems Engineering--Dissertations, Theses, and Student Research

One of the main goals of precision agriculture (PA) is to define spatial variability in soil properties within an agricultural field to make decisions that can maximize profitability and reduce negative environmental impact. Various soil sensor systems have been developed over the years to map soil properties on-the-go. In this study, an Integrated Soil Mapping System (ISMS) was developed to predict soil water content, soil organic matter, and soil mechanical resistance on-the-go using a capacitance moisture sensor, an optical sensor, and a load cell sensor respectively. These sensors were mounted on the ISMS for acquiring three different data layers at ...


Hydraulic Conductivity, Infiltration, And Runoff From No-Till And Tilled Cropland, Jessica H. Deck 2010 University of Nebraska-Lincoln

Hydraulic Conductivity, Infiltration, And Runoff From No-Till And Tilled Cropland, Jessica H. Deck

Biological Systems Engineering--Dissertations, Theses, and Student Research

Infiltration and runoff are important processes that affect the efficiency of center pivot irrigation systems. No-till planting systems potentially influence the hydraulic properties of soils and the soil surface conditions. The result of long-term use of no-till could be higher infiltration and lower runoff from rainfall and irrigation.

This potential was investigated in Nebraska on two center pivot irrigated sites; Fillmore County and Phelps County, one furrow irrigated site; South Central Agriculture Laboratory (SCAL), and one dryland site; Rogers Farm. Paired treatments were used at each location, one that was no-till planted and one that used two to three operations ...


Identification Of Holocarboxylase Synthetase Chromatin Binding Sites In Human Mammary Cell Lines Using The Damid Technology, Dipika Singh 2010 University of Nebraska-Lincoln

Identification Of Holocarboxylase Synthetase Chromatin Binding Sites In Human Mammary Cell Lines Using The Damid Technology, Dipika Singh

Biological Systems Engineering--Dissertations, Theses, and Student Research

Holocarboxylase synthetase (HCS) is a chromatin protein that is essential for mediating the covalent binding of biotin to histones. Biotinylation of histones plays crucial roles in the repression of genes and repeats in the human genome. The objective of this project was to determine genomic binding sites of holocarboxylase synthetase (HCS) in the human chromatin of breast cell lines using an antibody independent technology. We tested the feasibility of DNA adenine methyltransferase identification (DamID) technology to map HCS binding sites in human mammary cell lines. Full-length HCS was fused to Dam for subsequent transfection into breast cancer (MCF-7) and normal ...


The Development And Validation Of A Finite Element Model Of A Canine Rib For Use With A Bone Remodeling Algorithm., Scott J. Sylliaasen 2010 California Polytechnic State University, San Luis Obispo

The Development And Validation Of A Finite Element Model Of A Canine Rib For Use With A Bone Remodeling Algorithm., Scott J. Sylliaasen

Master's Theses

Studies are currently being performed to determine the effects of bisphosphonate treatments on the structure and density of bone tissue. One of the pathways for gaining a better understanding of the effects of this and other treatments involves creating a computer simulation. Theory suggests that bone tissue structure and density are directly related to the manner in which the tissue is loaded. Remodeling is the process in which bone tissue is resorbed in areas of low stress distributions, and generated in areas of high stress distributions. Previous studies have utilized numerical methods and finite element methods to predict bone structure ...


Microbiorobots For Single Cell Manipulation, Mahmut Selman Sakar 2010 University of Pennsylvania

Microbiorobots For Single Cell Manipulation, Mahmut Selman Sakar

Publicly Accessible Penn Dissertations

One of the great challenges in nano and micro scale science and engineering is the independent manipulation of biological cells and small man-made objects with active sensing. For such biomedical applications as single cell manipulation, telemetry, and localized targeted delivery of chemicals, it is important to fabricate microstructures that can be powered and controlled without a tether in fluidic environments. These microstructures can be used to develop microrobots that have the potential to make existing therapeutic and diagnostic procedures less invasive.

Actuation can be realized using various different organic and inorganic methods. Previous studies explored different forms of actuation and ...


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