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Combined Electrochemical Surface Plasmon Resonance For Angle Spread Imaging Of Multielement Electrode Arrays, Andrew C. Hillier, Chang Hoon Choi 2010 Iowa State University

Combined Electrochemical Surface Plasmon Resonance For Angle Spread Imaging Of Multielement Electrode Arrays, Andrew C. Hillier, Chang Hoon Choi

Chemical and Biological Engineering Publications

A surface plasmon resonance imaging system combined with a multielement electrode array is described. An optical system with shaping optics is used to direct a wedge of light onto a gold-coated sample. The reflected light is detected in the form of an angle-spread image of the surface, with one direction denoting a variable incident angle and the other showing a span of locations along one lateral direction of the sample surface. At the proper incident angle, the angle-spread image shows the complete surface plasmon resonance curve over a span of locations on the surface. This imaging system is combined with ...


Novel, High Throughput Method To Study In Vitro Protein Release From Polymer Nanospheres, L. K. Petersen, C. K. Sackett, Balaji Narasimhan 2010 Iowa State University

Novel, High Throughput Method To Study In Vitro Protein Release From Polymer Nanospheres, L. K. Petersen, C. K. Sackett, Balaji Narasimhan

Chemical and Biological Engineering Publications

Controlled delivery of therapeutic protein drugs using biodegradable polymer carriers is a desired characteristic that enables effective, application-specific therapy and treatment. Previous studies have focused on protein delivery from polymers using conventional "one-sample-at-a- time" techniques, which are time-consuming and costly. In addition, many therapeutic proteins are in limited supply and are expensive, so it is desirable to reduce sample size for design and development of delivery devices. We have developed a rapid, high throughput technique based on a highly sensitive fluorescence-based assay to detect and quantify protein released from polyanhydrides while utilizing relatively small amounts of protein (∼40 μg). These ...


An Extended Data Mining Method For Identifying Differentially Expressed Assay-Specific Signatures In Functional Genomic Studies, Derrick K. Rollins Sr., Ai-ling Teh 2010 Iowa State University

An Extended Data Mining Method For Identifying Differentially Expressed Assay-Specific Signatures In Functional Genomic Studies, Derrick K. Rollins Sr., Ai-Ling Teh

Chemical and Biological Engineering Publications

Background: Microarray data sets provide relative expression levels for thousands of genes for a small number, in comparison, of different experimental conditions called assays. Data mining techniques are used to extract specific information of genes as they relate to the assays. The multivariate statistical technique of principal component analysis (PCA) has proven useful in providing effective data mining methods. This article extends the PCA approach of Rollins et al. to the development of ranking genes of microarray data sets that express most differently between two biologically different grouping of assays. This method is evaluated on real and simulated data and ...


Testing An Exergame For Effectiveness And Attractiveness, Jeffrey Ronald Sinclair, Philip Hingston, Martin Masek, Kazunori Nosaka 2010 Edith Cowan University

Testing An Exergame For Effectiveness And Attractiveness, Jeffrey Ronald Sinclair, Philip Hingston, Martin Masek, Kazunori Nosaka

ECU Publications Pre. 2011

In this paper, we report on an experimental study in which we investigated the use of feedback mechanisms in exergames. We based the study around the Dual Flow model for exergame design, using biophysical feedback to control exercise intensity, and player performance feedback to control gameplay challenge. We found good success in controlling exercise intensity to achieve an effective workout, while controlling gameplay challenge to improve enjoyment and attractiveness was problematic. We offer some possible reasons for this, suggesting the need for further investigation.


Testing Fuel Efficiency Of A Tractor With A Continuously Variable Transmission, Bart A. Coffman, Michael F. Kocher, Viacheslav I. Adamchuk, Roger M. Hoy, Erin E. Blankenship 2010 University of Nebraska-Lincoln

Testing Fuel Efficiency Of A Tractor With A Continuously Variable Transmission, Bart A. Coffman, Michael F. Kocher, Viacheslav I. Adamchuk, Roger M. Hoy, Erin E. Blankenship

Biological Systems Engineering: Papers and Publications

A John Deere 8530 IVT tractor (Waterloo, Iowa) with a continuously variable transmission (CVT) that could be operated in automatic (CVT) or manual (fixed gear ratio) mode was tested for fuel consumption at a setpoint travel speed of 9 km·h‐1 with 17 different drawbar loads. Linear regression analysis results showed that with the throttle set to maximum in both transmission modes, operating the tractor with the transmission in the automatic mode was more fuel efficient than operating with the transmission in the manual mode when the drawbar power was approximately 78%, or less, of maximum power. When load ...


Modeling Changes In Biomass Composition During Microwave-Based Alkali Pretreatment Of Switchgrass, Deepak R. Keshwani, Jay J. Cheng 2010 University of Nebraska-Lincoln

Modeling Changes In Biomass Composition During Microwave-Based Alkali Pretreatment Of Switchgrass, Deepak R. Keshwani, Jay J. Cheng

Biological Systems Engineering: Papers and Publications

This study used two different approaches to model changes in biomass composition during microwave-based pretreatment of switchgrass: kinetic modeling using a time-dependent rate coefficient, and a Mamdani-type fuzzy inference system. In both modeling approaches, the dielectric loss tangent of the alkali reagent and pretreatment time were used as predictors for changes in amounts of lignin, cellulose, and xylan during the pretreatment. Training and testing data sets for development and validation of the models were obtained from pretreatment experiments conducted using 1–3% w/v NaOH (sodium hydroxide) and pretreatment times ranging from 5 to 20 min. The kinetic modeling approach ...


Dual-Stage Sugar Substitution In Strawberries With A Stevia-Based Sweetener, Juan Garcia-Noguera, Curtis L. Weller, Francisca I. P. Oliveira, Sueli Rodrigues, Fabiano A. N. Fernandes 2010 University of Nebraska-Lincoln

Dual-Stage Sugar Substitution In Strawberries With A Stevia-Based Sweetener, Juan Garcia-Noguera, Curtis L. Weller, Francisca I. P. Oliveira, Sueli Rodrigues, Fabiano A. N. Fernandes

Biological Systems Engineering: Papers and Publications

The present study introduces and analyzes a new process denominated dual-stage sugar substitution (D3S). This process aims to induce sugar substitution in strawberries. In a first stage, high-calorie sugars (sucrose, fructose and glucose) are partially removed from the fruit samples and in a second stage, low-calorie sugar (stevioside and rebaudioside) is incorporated to the fruit to maintain its sweetness. The process was evaluated by studying the use of ultrasound application in one or both stages of the D3S process. Best performance of the process was obtained by subjecting the fruit samples to ultrasound in the sugar removal stage followed by ...


Ultrasound-Assisted Osmotic Dehydration Of Strawberries: Effect Of Pretreatment Time And Ultrasonic Frequency, Juan Garcia-Noguera, Francisca I. P. Oliveira, Maria Izabel Gallão, Curtis L. Weller, Sueli Rodrigues, Fabiano A. N. Fernandes 2010 University of Nebraska-Lincoln

Ultrasound-Assisted Osmotic Dehydration Of Strawberries: Effect Of Pretreatment Time And Ultrasonic Frequency, Juan Garcia-Noguera, Francisca I. P. Oliveira, Maria Izabel Gallão, Curtis L. Weller, Sueli Rodrigues, Fabiano A. N. Fernandes

Biological Systems Engineering: Papers and Publications

Pretreatment of fruits prior to drying has shown success in reducing drying time and costs. In this work, ultrasound-assisted osmotic dehydration has been implemented as a method to increase water diffusivity and reduce drying time in strawberries. Strawberry halves were immersed in distilled water and in two different concentrations of sucrose solutions while pretreatment time and ultrasonic frequency levels were varied to determine their effect on drying time, water loss, and soluble solids gain. A microscopic analysis was carried out to evaluate the formation of microchannels and other changes to the fruit tissue structure. Greater sucrose concentration used in ultrasound- ...


Microwave-Based Alkali Pretreatment Of Switchgrass And Coastal Bermudagrass For Bioethanol Production, Deepak R. Keshwani, Jay J. Cheng 2010 University of Nebraska-Lincoln

Microwave-Based Alkali Pretreatment Of Switchgrass And Coastal Bermudagrass For Bioethanol Production, Deepak R. Keshwani, Jay J. Cheng

Biological Systems Engineering: Papers and Publications

Switchgrass and coastal bermudagrass are promising lignocellulosic feedstocks for bioethanol production. However, pretreatment of lignocelluloses is required to improve production of fermentable sugars from enzymatic hydrolysis. Microwave- based alkali pretreatment of switchgrass and coastal bermudagrass was investigated in this study. Pretreatments were carried out by immersing the biomass in dilute alkali reagents and exposing the slurry to microwave radiation at 250 W for residence times ranging from 5 to 20 min. Simons’ stain method was used to quantify changes in biomass porosity as a result of the pretreatment. Pretreatments were evaluated based on yields of total reducing sugars, glucose, and ...


Sulfated Zirconia Modified Sba-15 Catalysts For Cellobiose Hydrolysis, Volkan Degirmenci, Deniz Uner, Basak Cinlar, Brent H. Shanks, Aysen Yilmaz, Rutget A. van Santen, Emiel J. M. Hensen 2010 Middle East Technical University

Sulfated Zirconia Modified Sba-15 Catalysts For Cellobiose Hydrolysis, Volkan Degirmenci, Deniz Uner, Basak Cinlar, Brent H. Shanks, Aysen Yilmaz, Rutget A. Van Santen, Emiel J. M. Hensen

Chemical and Biological Engineering Publications

Zirconia modified SBA-15 becomes a very active catalyst for the selective hydrolysis of cellobiose to glucose after sulfation. Spectroscopic investigations indicate the presence of Brønsted acid sites with similar properties to those present in conventional sulfated zirconia. Indications are found that the sulfate groups attached to zirconia interact with silanol groups of SBA-15. The catalytic activity in cellobiose hydrolysis correlates well with results for temperature-programmed decomposition of i-propylamine for a range of sulfated ZrO2/SBA-15 catalysts. A glucose yield of 60% during cellobiose hydrolysis at a reaction time of 90 min at 160° C is obtained.


Conversion Of Biorenewable Feedstocks: New Challenges In Heterogeneous Catalysis, Brent H. Shanks 2010 Iowa State University

Conversion Of Biorenewable Feedstocks: New Challenges In Heterogeneous Catalysis, Brent H. Shanks

Chemical and Biological Engineering Publications

For biorenewable feedstocks to serve as a significant source of chemicals and/or fuels, the development of new chemical processes as well as biological processes will be required. However, the conversion of biorenewable feedstocks with heterogeneous catalyst-based processes provides new challenges in inorganic catalyst research and development relative to historical work with petrochemical feedstocks. These catalyst and process challenges include the need to convert highly functionalized molecules with high selectivity, to develop stable catalytic liquid-solid interfaces in which the liquid phase is commonly aqueous, to control solvent phase effects and to develop novel reaction systems. While some of these challenges ...


Metabolic Analysis Of Wild-Type Escherichia Coli And A Pyruvate Dehydrogenase Complex (Pdhc)-Deficient Derivative Reveals The Role Of Pdhc In The Fermentative Metabolism Of Glucose, Abhishek Murarka, James M. Clomburg, Sean Moran, Jacqueline V. Shanks, Ramon Gonzalez 2010 Rice University

Metabolic Analysis Of Wild-Type Escherichia Coli And A Pyruvate Dehydrogenase Complex (Pdhc)-Deficient Derivative Reveals The Role Of Pdhc In The Fermentative Metabolism Of Glucose, Abhishek Murarka, James M. Clomburg, Sean Moran, Jacqueline V. Shanks, Ramon Gonzalez

Chemical and Biological Engineering Publications

Pyruvate is located at a metabolic junction of assimilatory and dissimilatory pathways and represents a switch point between respiratory and fermentative metabolism. In Escherichia coli, the pyruvate dehydrogenase complex (PDHC) and pyruvate formate-lyase are considered the primary routes of pyruvate conversion to acetyl-CoA for aerobic respiration and anaerobic fermentation, respectively. During glucose fermentation, the in vivo activity of PDHC has been reported as either very low or undetectable, and the role of this enzyme remains unknown. In this study, a comprehensive characterization of wild-type E. coli MG1655 and a PDHC-deficient derivative (Pdh) led to the identification of the role of ...


Integration Mechanisms For Heading Perception, Elif M. Sikoglu, Finnegan J. Calabro, Scott A. Beardsley, Lucia M. Vaina 2010 Boston University

Integration Mechanisms For Heading Perception, Elif M. Sikoglu, Finnegan J. Calabro, Scott A. Beardsley, Lucia M. Vaina

Biomedical Engineering Faculty Research and Publications

Previous studies of heading perception suggest that human observers employ spatiotemporal pooling to accommodate noise in optic flow stimuli. Here, we investigated how spatial and temporal integration mechanisms are used for judgments of heading through a psychophysical experiment involving three different types of noise. Furthermore, we developed two ideal observer models to study the components of the spatial information used by observers when performing the heading task. In the psychophysical experiment, we applied three types of direction noise to optic flow stimuli to differentiate the involvement of spatial and temporal integration mechanisms. The results indicate that temporal integration mechanisms play ...


Quadrature-Based Moment Model For Moderately Dense Polydisperse Gas-Particle Flows, Rodney O. Fox, Prakash Vedula 2010 Iowa State University

Quadrature-Based Moment Model For Moderately Dense Polydisperse Gas-Particle Flows, Rodney O. Fox, Prakash Vedula

Chemical and Biological Engineering Publications

A quadrature-based moment model is derived for moderately dense polydisperse gas-particle flows starting from the inelastic Boltzmann-Enskog kinetic equation including terms for particle acceleration (e.g., gravity and fluid drag). The derivation is carried out for the joint number density function, f(t,x,m,u), of particle mass and velocity, and thus, the model can describe the transport of polydisperse particles with size and density differences. The transport equations for the integer moments of the velocity distribution function are derived in exact form for all values of the coefficient of restitution for particle-particle collisions. For particular limiting cases, the ...


Utilizing Protein-Lean Coproducts From Corn Containing Recombinant Pharmaceutical Proteins For Ethanol Production, Ilankovan Paraman, Lorena Beatriz Moeller, M. Paul Scott, Kan Wang, Charles E. Glatz, Lawrence A. Johnson 2010 Iowa State University

Utilizing Protein-Lean Coproducts From Corn Containing Recombinant Pharmaceutical Proteins For Ethanol Production, Ilankovan Paraman, Lorena Beatriz Moeller, M. Paul Scott, Kan Wang, Charles E. Glatz, Lawrence A. Johnson

Chemical and Biological Engineering Publications

Protein-lean fractions of corn (maize) containing recombinant (r) pharmaceutical proteins were evaluated as a potential feedstock to produce fuel ethanol. The levels of residual r-proteins in the coproduct, distillers dry grains with solubles (DDGS), were determined. Transgenic corn lines containing recombinant green fluorescence protein (r-GFP) and a recombinant subunit vaccine of Escherichia coli enterotoxin (r-LTB), primarily expressed in endosperm, and another two corn lines containing recombinant human collagen (r-CIα1) andr-GFP, primarily expressed in germ, were used as model systems. The kernels were either ground and used for fermentation or dry fractionated to recover germ-rich ...


Cytocompatible Cross-Linking Of Electrospun Zein Fibers For The Development Of Water-Stable Tissue Engineering Scaffolds, Quiran Jiang, Narendra Reddy, Yiqi Yang 2010 University of Nebraska–Lincoln

Cytocompatible Cross-Linking Of Electrospun Zein Fibers For The Development Of Water-Stable Tissue Engineering Scaffolds, Quiran Jiang, Narendra Reddy, Yiqi Yang

Biological Systems Engineering: Papers and Publications

This paper reports a new method of cross-linking electrospun zein fibers using citric acid as a non-toxic cross-linker to enhance the water stability and cytocompatibility of zein fibers for tissue engineering and other medical applications. The electrospun structure has many advantages over other types of structures and protein-based biomaterials possess unique properties preferred for tissue engineering and other medical applications. However, ultrafine fiber matrices developed from proteins have poor mechanical properties and morphological stability in the aqueous environments required for medical applications. Efforts have been made to improve the water stability of electrospun protein scaffolds using cross-linking and other approaches ...


Preferential Flow Effects On Subsurface Contaminant Transport In Alluvial Floodplains, Derek M. Heeren, Ron B. Miller, Garey A. Fox, Daniel E. Storm, Todd Halihan, Chad J. Penn 2010 University of Nebraska-Lincoln

Preferential Flow Effects On Subsurface Contaminant Transport In Alluvial Floodplains, Derek M. Heeren, Ron B. Miller, Garey A. Fox, Daniel E. Storm, Todd Halihan, Chad J. Penn

Biological Systems Engineering: Papers and Publications

For sorbing contaminants, transport from upland areas to surface water systems is typically considered to be due to surface runoff, with negligible input from subsurface transport assumed. However, certain conditions can lead to an environment where subsurface transport to streams may be significant. The Ozark region, including parts of Oklahoma, Arkansas, and Missouri, is one such environment, characterized by cherty, gravelly soils and gravel bed streams. Previous research identified a preferential flow path (PFP) at an Ozark floodplain along the Barren Fork Creek in northeastern Oklahoma and demonstrated that even a sorbing contaminant, i.e., phosphorus, can be transported in ...


Testing Of Rtk-Level Satellite-Based Tractor Auto-Guidance Using A Visual Sensor System, Dwight Easterly, Viacheslav I. Adamchuk, Roger M. Hoy, Michael F. Kocher 2010 University of Nebraska-Lincoln

Testing Of Rtk-Level Satellite-Based Tractor Auto-Guidance Using A Visual Sensor System, Dwight Easterly, Viacheslav I. Adamchuk, Roger M. Hoy, Michael F. Kocher

Biological Systems Engineering: Papers and Publications

The use of satellite-based positioning has advanced considerably in the world of agriculture, providing a range of technical solutions that include the automated steering of tractors and self-propelled machinery. With the development of auto-guidance systems comes the need to evaluate their performance. Given that current precision and accuracy claims are relatively small in magnitude, it is imperative there be a testing system capable of detecting errors with ten times greater accuracy-- possibly as little as a few millimeters. A visual sensor was adopted to achieve this level of measurement resolution. The sensor was used to determine the cross-track error estimates ...


A Comrehensive Model Study For Flash Nanoprecipitation: Computational Fluid Dynamics, Micro- Particle Image Velocimetry, And Population Balance Modeling, Janine Chungyin Cheng 2010 Iowa State University

A Comrehensive Model Study For Flash Nanoprecipitation: Computational Fluid Dynamics, Micro- Particle Image Velocimetry, And Population Balance Modeling, Janine Chungyin Cheng

Graduate Theses and Dissertations

A model study has been conducted for Flash Nanoprecipitation(FNP)) - a novel approach to produce functional nanoparticles. A mixing study has been conducted in a custom-designed microscale multi-inlet vortex reactor (MIVR) and a scalar mixing model was validated against experimental data. A microPIV experiment was conducted to further validate the turbulent model. A population balance equation (PBE) has been proposed to model the FNP process. It was furthermore, integrated into a computational fluid dynamics (CFD) simulation of to yield conditions comparable to the real experimental settings. In coping with the complicated aggregation model in the CFD code, a new numerical ...


Electrohydrodynamic Atomization For Improved Macromolecular Drug Delivery, Michelle Zeles-Hahn 2010 University of Denver

Electrohydrodynamic Atomization For Improved Macromolecular Drug Delivery, Michelle Zeles-Hahn

Electronic Theses and Dissertations

With advances in drug research, the use of biological therapeutics is becoming a reality. Unfortunately, methods for processing and delivering these fragile macromolecules often limit their therapeutic potential. For this dissertation, we explore the aerosolization of macromolecules by way of electrohydrodynamic atomization (EHDA) and how this method can be used to process and deliver therapeutics. EHDA employs a high voltage to break a column of liquid into drops. It was unknown if or how the residual charge left of the resulting droplets would affect lung cells. An in vitro experiment was conducted to spray aerosolized DNA, by way of EHDA ...


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