Digital Commons Network^™

Nature - Nanotechnology-Live Wire, Ravi F. Saraf, Vikas Berry

Department of Chemical and Biomolecular Engineering: News Releases

No Abstact.

Application Of Polyelectrolyte Layer-By-Layer Nano-Assembly For Surface Modification, Encapsulation And Controlled Release, Nikhil Anil Pargaonkar

Doctoral Dissertations

In this study, we applied the traditional Electrostatic layer-by-layer (ELBL) assembly procedure to fabricate nanothin films over flat surfaces, and modify particle surfaces to influence the drug particle size, and drug release. The ELBL assembly has previously been applied to fabricate multilayer nano-scale thin films, but its ability to instantaneously influencing particle size is unique. Other unique observations such as influence on drug release as a result of polymer complexation, and thermal changes occurring during layer fabrication are recorded.

The ELBL self-assembly process was applied to produce dexamethasone particles layered with various polyelectrolyte layer combinations. These combinations were further applied …

Perceived Competence Of Aging Pilots, Laura M. Stelmach

Master's Theses - Daytona Beach

This study investigated the relationship between age and the perception of competence of pilots by the traveling public. Scenarios were utilized that depicted an airline captain successfully landing an airplane amidst adverse conditions. Scenarios varied only by the age of the Captain: Young, Old, or Unspecified Age and that the Young and Old scenarios included a photo of the captain. Perceived effectiveness, competence, avoidance, blame, and attribution as depicted by the Captain's performance in the scenario were assessed by 180 participants in three age groups (18-34, 35-55, and 56

Use Of 16s Rrna Gene Terminal Restriction Fragment Analysis To Assess The Impact Of Solids Retention Time On The Bacterial Diversity Of Activated Sludge, Pascal E. Saikaly, Peter George Stroot, Daniel B. Oerther

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Terminal restriction fragment length polymorphism (T-RFLP) analysis of 16S rRNA genes was used to investigate the reproducibility and stability in the bacterial community structure of laboratory-scale sequencing batch bioreactors (SBR) and to assess the impact of solids retention time (SRT) on bacterial diversity. Two experiments were performed. In each experiment two sets of replicate SBRs were operated for a periods of three times the SRT. One set was operated at an SRT of 2 days and another set was operated at an SRT of 8 days. Samples for T-RFLP analysis were collected from the two sets of replicate reactors. HhaI, …

Engineering@Nebraska - Fall 2005

Engineering@Nebraska (Alumni Magazine)

Table of Contents:

Celebrating 10 Years of Educating Young Minds: After 10 years, Edgerton Explorit Center continues the mission of its namesake—to enlighten curious minds and enhance our understanding of the world.
Helping Hands...and Wrists: Professor gives doctors a helping hand with newly patented IntuiTool™
The Greater Good: Service learning allows students to put their education to work for the good of the community.
Cool Under Fire: Second generation of Scherzbergs carries on the tradition of school and service to country.
The Future of Nebraska Engineering: The college’s new strategic plan looks at ways research can serve federal and state …

Nebraska Blueprint - Fall 2005

Nebraska Blueprint (Student Publication)

Table of Contents:

Letter from the editor by Frank Pribyl
Contributors
Humanoid robotics
Gravity Galore by Celica Orwig
CGI: Computer Generated Imagery
Learn a word: Hologram
UNL mini baja team

Development Of Palladium Nanowires, Chuanding Cheng

Doctoral Dissertations

Inherent limitations of traditional lithography have prompted the search for means of achieving self-assembly of nano-scale structures and networks for the next generation of electronic and photonic devices. The nanowire, the basic building block of a nanocircuit, has recently become the focus of intense research. Reports on nanowire synthesis and assembly have appeared in the scientific literature, which include Vapor-Liquid-Solid mechanism, template-based electrochemical fabrication, solvothermal or wet chemistry, and assembly by fluid alignment or microchannel networks. An ideal approach for practical application of nanowires would circumvent technical and economic constraints of templating. Here we report on the self-assembly of highly-ordered …

Cs/Bio 471/671: Algorithms For Bioinformatics, Michael L. Raymer

Computer Science & Engineering Syllabi

Theory-oriented approach to the application of contemporary algorithms to bioinformatics. Graph theory, complexity theory, dynamic programming and optimization techniques are introduced in the context of application toward solving specific computational problems in molecular genetics.

Cs/Mth 316/516: Numerical Methods For Digital Computers, Ronald F. Taylor

Computer Science & Engineering Syllabi

Introduction to numerical methods used in the sciences. Methods of interpolation, data smoothing, functional approximation, numerical differentiation and integration. Solution techniques for linear and nonlinear equations. Discussion of sources of error in numerical methods. Applications of interest to engineering, science, and applied mathematics students are an integral part of the course. Special topics presented as schedule permits.

Ozone Concentration In An Atmospheric Pressure Air Plasma Jet, Srinivas Reddy Suddala

Electrical & Computer Engineering Theses & Dissertations

A stable micro-plasma jet in air was generated from a direct current discharge between two molybdenum electrodes (0.25 mm thick) that were separated by an alumina insulator of the same thickness. The after-glow plasma jet was generated by blowing air through the space between the electrodes. A change from laminar to turbulent flow was observed at a gas flow rate of 140 ml/min. The length of the plasma jet increased with flow rate in the laminar mode to approximately 15 mm and decreased in the turbulent mode.

Increasing the gas flow rate up to 200 ml/min at a constant discharge …

Intravenous Polyethylene Glycol Inhibits The Loss Of Cerebral Cells After Brain Injury, Andrew O. Koob, Bradley S. Duerstock, Charles F. Babbs, Yinlong Sun, Richard B. Borgens

Weldon School of Biomedical Engineering Faculty Publications

We have tested the effectiveness of polyethylene glycol (PEG) to restore the integrity of neuronal membranes after mechanical damage secondary to severe traumatic brain injury (TBI) produced by a standardized head injury model in rats. We provide additional detail on the standardization of this model, particularly the use and storage of foam bedding that serves to both support the animal during the impact procedure and to dampen the acceleration of the brass weight. Further, we employed a dye exclusion technique using ethidium bromide (EB; quantitative evaluation) and horseradish peroxidase (HRP; qualitative evaluation). Both have been successfully used previously to evaluate …

Effect Of Viscoelasticity On Quality Factor Of Microcantilever Chemical Sensors: Optimal Coating Thickness For Minimum Limit Of Detection, F. Lochon, Isabelle Dufour, D. Rebière, U. Sampath, Stephen M. Heinrich, Fabien Josse

Civil and Environmental Engineering Faculty Research and Publications

Microcantilevers with polymer coatings hold great promise as resonant chemical sensors. It is known that the coated cantilever sensitivity increases with coating thickness; however, the drawback of increasing the coating thickness is the increase of the frequency noise and thus the deterioration of the sensor's limit of detection. In this paper, an analytical expression for the viscoelastic losses in the coating, hence the quality factor is established and is used to explain the observed increase of the frequency noise with the polymer thickness. This result is then used to demonstrate that an optimum coating thickness exists that minimise the limit …

Axial Stent Strut Angle Influences Wall Shear Stress After Stent Implantation: Analysis Using 3d Computational Fluid Dynamics Models Of Stent Foreshortening, John F. Ladisa, Lars E. Olson, Douglas Anthony Hettrick, David C. Warltier, Judy R. Kersten, Paul S. Pagel

Biomedical Engineering Faculty Research and Publications

Introduction

The success of vascular stents in the restoration of blood flow is limited by restenosis. Recent data generated from computational fluid dynamics (CFD) models suggest that the vascular geometry created by an implanted stent causes local alterations in wall shear stress (WSS) that are associated with neointimal hyperplasia (NH). Foreshortening is a potential limitation of stent design that may affect stent performance and the rate of restenosis. The angle created between axially aligned stent struts and the principal direction of blood flow varies with the degree to which the stent foreshortens after implantation.

Methods

In the current investigation, we …

Fourier Transform Analysis Of Terahertz Radiation, Chikaodira N. Okpo

Electrical & Computer Engineering Theses & Dissertations

Advances in terahertz radiation (T-rays) technology have great promise in various technological areas ranging from medical technology, imaging technology and accelerator technology. At Thomas Jefferson Laboratory, the Free Electron Laser division (FEL) produces very powerful beam of laser light by accelerating electrons in bunches along a beamline. This laser light absorbs and releases energy at various wavelengths. The new FEL upgrade led to the production of very bright terahertz (THz) radiation with an average power of 1 00watts which is about 100,000 times brighter than those produced elsewhere. These T-rays have very significant applications in the Laboratory. The most significant …

Structure Of Human Thymidylate Synthase Under Low-Salt Conditions, Leslie L. Lovelace, Wladek Minor, Lukasz Lebioda

Faculty Publications

Human thymidylate synthase, a target in cancer chemotherapy, was crystallized from PEG 3350 with 30 mM ammonium sulfate (AS) in the crystallization medium. The crystals are isomorphous with the high-salt crystals (~2.0 M AS) and the structure has been solved and refined (R = 22.6%, Rfree = 24.3%) at 1.8 Å resolution. The high- and low-AS-concentration structures are quite similar, with loop 181-197 is in the inactive conformation. Also, residues 95-106 and 129-135 (eukaryotic inserts region) show high mobility as assessed by poor electron density and high values of crystallographic temperature factors (residues 1-25 and 108-129 are disordered in both …

Polymer-Mediated Synthesis Of Highly Dispersed Pt Nanoparticles On Carbon Black, Min Chen, Yangchuan Xing

Chemical and Biochemical Engineering Faculty Research & Creative Works

A new method was developed to prepare highly dispersed Pt nanoparticles on carbon black to use as proton exchange membrane (PEM) fuel cell catalysts. This method involves using a polymer, poly-(vinylpyrrolidone) (PVP), to prevent particle aggregation and thereby reduce nanoparticle sizes to achieve high dispersion. It was found that Pt nanoparticles mediated by PVP are smaller than those obtained without PVP and have a narrower size distribution. Well-dispersed Pt nanoparticles with metal loadings from 5 to 35 wt % were obtained on carbon black (Vulcan XC-72R). It was found that well-dispersed Pt nanoparticles on carbon black could be synthesized at …

Enhancement Of Protein Secretion In Pichia Pastoris By Overexpression Of Protein Disulfide Isomerase, Mehmet İnan, Dinesh Aryasomayajula, Jayanta Sinha, Michael M. Meagher

Papers in Biochemical Engineering

A potential vaccine candidate, Necator americanus secretory protein (Na-ASP1), against hookworm infections, has been expressed in Pichia pastoris. Na- ASP1, a 45 kDa protein containing 20 cysteines, was directed outside the cell by fusing the protein to the preprosequence of the α-mating factor of Saccharomyces cerevisiae. Most of the protein produced by single copy clones was secreted outside the cell. However, increasing gene copy number of Na-ASP1 protein in P. pastoris saturated secretory capacity and therefore, decreased the amount of secreted protein in clones harboring multiple copies of Na-ASP1 gene. Overexpression of the …

A Motion Planning Processor On Reconfigurable Hardware, Nuzhet Atay, Burchan Bayazit

All Computer Science and Engineering Research

Motion planning algorithms enable us to find feasible paths for moving objects. These algorithms utilize feasibility checks to differentiate valid paths from invalid ones. Unfortunately, the computationally expensive nature of such checks reduces the effectiveness of motion planning algorithms. However, by using hardware acceleration to speed up the feasibility checks, we can greatly enhance the performance of the motion planning algorithms. Of course, such acceleration is not limited to feasibility checks; other components of motion planning algorithms can also be accelerated using specially designed hardware. A Field Programmable Gate Array (FPGA) is a great platform to support such an acceleration. …

Usability Over Time, Valerie Mendoza, David G. Novick

Departmental Papers (CS)

Testing of usability could perhaps be more accurately described as testing of learnability. We know more about the problems of novice users than we know of the problems of experienced users. To understand how these problems differ, and to understand how usability problems change as users change from novice to experienced, we conducted a longitudinal study of usability among middle-school teachers creating Web sites. The study looked at the use both the use of documentation and the underlying software, tracking the causes and extent of user frustration over eight weeks. We validated a categorization scheme for frustration episodes. We found …

Cgmp Recombinant Fix For Iv And Oral Hemophilia B Therapy, William H. Velander Principal Investigator, Abramson Stephan Lead Investigator, Cooper Julian Lead Investigator, William Dernell Key Person, Mark Manning Lead Investigator, Michael Meagher Lead Investigator, Paul Mohanan Lead Investigator, Timothy Nichols Lead Investigator, Todd Swaanson Key Person, Kevin E. Van Cott

Department of Chemical and Biomolecular Engineering: Funded Proposals

Three specific aims are proposed: Specific Aim # 1. Process engineer and scale-up the recovery and purification of transgenic recombinant human Factor IX. The University of Nebraska-Lincoln Biological Process Development Facility will complete process development and scale-up, and produce clinical grade materials for preclinical studies. The endpoint is a proposed final product specification to help facilitate transfer to current Good Manufacturing Practices compliant production of clinical grade material to support an Investigational New Drug filing with the United States Food and Drug Administration (FDA) leading to clinical trials. Specific Aim #2. Characterize and formulate transgenic recombinant human Factor IX for …

Microbial Quality Of Runoff Following Land Application Of Cattle Manure And Swine Slurry, Jeanette A. Thurston-Enriquez, John E. Gilley, Bahman Eghball

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Concentrations of human health-related microorganisms in runoff from agricultural plots (0.75m x 2m) treated with fresh and aged cattle manure, swine slurry and no manure (control) were determined. Three consecutive simulated rainfall events, producing 35 mm rainfall and separated by 24 h, were carried out for each plot. Fecal indicator (Escherichia coli, enterococci, Clostridium perfringens and coliphage) loads released in rainfall runoff from plots treated with fresh cattle manure, aged cattle manure and swine slurry treatments ranged from 5.52 x 10⁵ to 4.36 x 10⁹, 3.92 x 10⁴ to 4.86 x 10⁸, and 9.63 …

Biophysics Of Cardiopulmonary Resuscitation With Periodic Z-Axis Acceleration Of Abdominal Compression At Aortic Resonant Frequencies, Charles F. Babbs

Weldon School of Biomedical Engineering Faculty Publications

Periodic z-axis acceleration (pGz)-CPR involves oscillating motion of a whole patient in the head-to-foot dimension on a mechanized table. The method is able to sustain blood flow and long-term survival during and after prolonged cardiac arrest in anesthetized pigs. However, the exact mechanism by which circulation of blood is created has remained unknown. Objectives: To explain the hemodynamic mechanism of pGz-CPR and to suggest theoretically useful improvements. Method: Computer modeling using a hybrid analytical-numerical approach, based upon Newton’s second law of motion for fluid columns in the aorta and vena cavae, Ohm’s law for resistive flow through vascular beds, and …

Quantifying The Effect Of A Vegetated Littoral Zone On Wet Detention Pond Pollutant Load Reduction (2005), Stormwater Academy

BMP Trains Research and Publications

This report describes an investigation sponsored by the Florida Department of Environmental Protection (FDEP), in which DB Environmental, Inc., with assistance from Community Watershed Fund, evaluated the potential of littoral zone vegetation to enhance contaminant removal performance of a wet detention pond.

For this effort, we constructed an experimental facility at a 1 hectare wet detention pond in Brevard Co, Florida that contained pre-existing littoral vegetation (distinct stands of cattail (Typha sp.) and pickerelweed (Pontederia cordata)) in addition to an unvegetated shoreline. Ten compartments, 3.7 m by 9.0 m, were deployed within the facility, effectively isolating sections of the pond. …

Substrate-Mediated Delivery From Self-Assembled Monolayers: Effect Of Surface Ionization, Hydrophilicity, And Patterning, Angela K. Pannier, Brian C. Anderson, Lonnie D Shea

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Gene transfer has many potential applications in basic and applied sciences. In vitro, DNA delivery can be enhanced by increasing the concentration of DNA in the cellular microenvironment through immobilization of DNA to a substrate that supports cell adhesion. Substrate-mediated delivery describes the immobilization of DNA, complexed with cationic lipids or polymers, to a biomaterial or substrate. As surface properties are critical to the efficiency of the surface delivery approach, selfassembled monolayers (SAMs) of alkanethiols on gold were used to correlate surface chemistry of the substrate to binding, release, and transfection of non-specifically immobilized complexes. Surface hydrophobicity and ionization were …

The Processing, Mechanical Properties And Bioactivity Of Zinc Based Glass Ionomer Cements, D. Boyd, Mark R. Towler

Chemical and Biochemical Engineering Faculty Research & Creative Works

The suitability of Glass Ionomer Cements (GICs) for use in orthopaedics is retarded by the presence in the glass phase of aluminium, a neurotoxin. Unfortunately, the aluminium ion plays an integral role in the setting process of a GIC and its absence is likely to hinder cement formation. However, zinc oxide, a bacteriocide, can act both as a network modifying oxide and an intermediate oxide in a similar fashion to alumina and so ternary systems based on zinc silicates often have extensive regions of glass formation. The purpose of this research was to produce novel GICs based on calcium zinc …

Contrast-Detail Analysis Characterizing Diffuse Optical Fluorescence Tomography Image Reconstruction, Scott C. Davis, Brian W. Pogue, Hamid Dehghani, Keith D. Paulsen

Dartmouth Scholarship

Contrast-detail analysis is used to evaluate the imaging performance of diffuse optical fluorescence tomography (DOFT), characterizing spatial resolution limits, signal-to-noise limits, and the trade-off between object contrast and size. Reconstructed images of fluorescence yield from simulated noisy data were used to determine the contrast-to-noise ratio (CNR). A threshold of CNR=3 was used to approximate a lowest acceptable noise level in the image, as a surrogate measure for human detection of objects. For objects 0.5 cm inside the edge of a simulated tissue region, the smallest diameter that met this criteria was approximately 1.7 mm, regardless of contrast level, and test …

Protein Impregnated Polymer (Pip) Film Infrared Sensor Using Suspended Microelectromechanical Systems (Mems) Pixels, Tetsuo Kaieda

Theses and Dissertations

The Air Force Research Laboratory Materials and Manufacturing Directorate have developed a novel protein impregnated polymer (PIP) suspension that changes resistivity as a function of absorbed infrared radiation. Due to this property, the PIP is a potential material for use as an uncooled bolometer, or thermal sensor. In this research, a thermally-isolated pixel design, sensor characterization methods, and sensor fabrication and processing steps were developed. To create a microbolometer, the PIP was applied to two prototype micro-electro-mechanical systems (MEMS) surface micro-machined structures. The first is a raised cantilever pixel array that uses residual stress polysilicon and metal film arms to …

Establishment Of A System Operating Characteristic For Autonomous Wide Area Search Vehicles, Brian A. Kish

Theses and Dissertations

The optimal employment of autonomous search and destroy vehicles is addressed. The results apply to air, land, or water vehicles with 1, k, or infinite warheads. The specific scenarios considered involve an air vehicle searching a battle space for stationary targets in the presence of false targets. Encounters are modeled with uniform, Poisson, and normal distributions. Linear and circular search patterns are examined. All relevant parameters are extracted from intelligence information, the sensor performance specification, and the air vehicle performance specification. Analytic system effectiveness measures are derived using applied probability theory. The effectiveness measures derived in this dissertation handle time-varying …

Combat Identification With Sequential Observations, Rejection Option, And Out-Of-Library Targets, Timothy W. Albrecht

Theses and Dissertations

This research extends a mathematical framework to select the optimal sensor ensemble and fusion method across multiple decision thresholds subject to warfighter constraints for a combat identification (CID) system. The formulation includes treatment of exemplars from target classes on which the CID system classifiers are not trained (out-of-library classes) and enables the warfighter to optimize a CID system without explicit enumeration of classifier error costs. A time-series classifier design methodology is developed and applied, yielding a multi-variate Gaussian hidden Markov model (HMM). The extended CID framework is used to compete the HMM-based CID system against a template-based CID system. The …

Automated Liquid Dispensing Pin For Dna Microarray Applications, Suganya Parthasarathy

Theses

This thesis describes the research and development of a new liquid dispensing/aspiring system that is capable of producing micro sized spots/droplets for molecular biology research and analysis. In particular, the application is focused on DNA microarray fabrication with the goals of smaller spot size, higher yield, more efficient usage of biological materials, and capability to handle high viscosity liquids. The new system is based on active sensing and control and it is part of a fully integrated robotic microarray system for genomic and proteomic applications. The prototype system handles water as well as thick liquids such as 100% glycerol and …