Engineering Commons^™

Monitoring Tissue Engineering Using Magnetic Resonance Imaging, Huihui Xu, Shadi F. Othman, Richard L. Magin

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Assessment of tissue regeneration is essential to optimize the stages of tissue engineering (cell proliferation, tissue development and implantation). Optical and X-ray imaging have been used in tissue engineering to provide useful information, but each has limitations: for example, poor depth penetration and radiation damage. Magnetic resonance imaging (MRI) largely overcomes these restrictions, exhibits high resolution (approximately 100 μm) and can be applied both in vitro and in vivo. Recently, MRI has been used in tissue engineering to generate spatial maps of tissue relaxation times (T₁, T₂), water diffusion coefficients, and the stiffness (shear moduli) of …

Quantitative Rrna-Targeted Solution-Based Hybridization Assay Using Peptide Nucleic Acid Molecular Beacons, Xu Li, Eberhard Morgenroth, Lutgarde Raskin

Department of Civil and Environmental Engineering: Faculty Publications

The potential of a solution-based hybridization assay using peptide nucleic acid (PNA) molecular beacon (MB) probes to quantify 16S rRNA of specific populations in RNA extracts of environmental samples was evaluated by designing PNA MB probes for the genera Dechloromonas and Dechlorosoma. In a kinetic study with 16S rRNA from pure cultures, the hybridization of PNA MB to target 16S rRNA exhibited a higher final hybridization signal and a lower apparent rate constant than the hybridizations to nontarget 16S rRNAs. A concentration of 10 mM NaCl in the hybridization buffer was found to be optimal for maximizing the difference between …

Nano-Raman Spectroscopy And Surface Nanostructuring Using Near-Field Optics, Kaijun Yi

Department of Electrical and Computer Engineering: Dissertations, Theses, and Student Research

To satisfy the development of nanoscience and nanotechnology, techniques to characterize and fabricate nanostructures and nanodevices are in great demand. Laser, as a unique monochromatic and coherent light source, meets the needs because it exhibits the potential to reveal some vital information of the materials. However, the applications of laser technology to nanoscience and nanotechnology are facing a severe challenge: the spatial resolution cannot be further enhanced to achieve nanometer scales due to the optical diffraction limit associated with conventional optics. In response to this challenge, near-field optics has been emerging as a new scientific area to deal with optical …

Structural Nanocomposites, Yuris A. Dzenis

Nebraska Center for Materials and Nanoscience: Faculty Publications

Materials scientists predict that composites made with nanoscale reinforcing materials such as nanotubes, platelets, and nanofibers will have exceptional mechanical properties. However, the results obtained so far are disappointing, particularly when compared to advanced composites reinforced with high-performance continuous fibers (1–4). The reasons include inadequate dispersion and alignment of the nanoreinforcement, low nanoreinforcement volume fraction, and poor bonding and load transfer at interfaces. Intensive work is under way, but the prospect of bulk structural supernanocomposites appears more remote now than it did just a few years ago. However, recent work shows that some applications in reinforcement of small structures may …

Regulating Self-Organizing Nanostructures Via External Mechanism, Jiangyu Li, Q. G. Du, Stephen Ducharme

Stephen Ducharme Publications

Self-organizing nanostructures are ubiquitous in both natural and synthetic materials. They are not only appealing scientifically, by revealing the intrinsic atomic and molecular interactions that might be difficult to detect otherwise, but may also hold the key for the development of novel functional structures and devices. For their technological potential to be fully realized, the size, morphology, and distribution of the self-organizing nanostructures must be regulated. In this paper, we investigate the principles under which the self-organizing nanostructures can be regulated via external mechanisms. Using nanomesa and nanowell formation in polyvinylidene fluoride trifluoroethylene copolymer film as an example, we demonstrate …

Economic Development Benefits From Wind Power In Nebraska: A Report For The Nebraska Energy Office, E. Lantz

United States Department of Energy: Publications

Wind power constituted more than 35% of new U.S. electric generating capacity in 2007. Common drivers of wind power include Renewable Portfolio Standards (RPS), the federal production tax credit (PTC), and rural economic development benefits. Continued expansion of the wind industry into Nebraska would bring new employment and economic development to Nebraska and the country. This report by the National Renewable Energy Laboratory (NREL) focuses on the economic development impacts that would result in Nebraska from development and operation of wind power in the state as envisioned in the U.S. Department of Energy’s (DOE’s) report 20% Wind Energy by 2030 …

Acuta Enews November 2008, Vol. 37, No. 11

ACUTA Newsletters

In This lssue

From ACUTA Headquarters: FCC lssues Rules to lmplement NET 91 1 ACT........ Jeri Semer, CAE, Exec. Dir

Tech Talk: For Most, the Big Change on Campus ls Wireless.............Kevin Tanzillo, Dux PR

DC Update.............. Dove Ostrom, Washlngton State University

Nominate Now for ACUTA Board of Directors

Be a State/Province Coordinator

Teflon:A Dangerous Part of a High-Risk World.................Frank Bisbee, Wireville USA

Thanks to Exhibitors for 2008

lnfo Links ............. Randy Hayes, Univ. of Northern lowa

Board Report, October....................... Riny Ledgenuood, San Diego State Univ.

Welcome New Members

Check lt Out: RFls/RFPs, Job Postings, Press Releases

Summer Sessions Breakdown Of Course Dates And Time, Paul Savory

Department of Industrial and Management Systems Engineering: Faculty Publications

This report highlights an exhaustive analysis of the hundreds of Summer Session courses to develop an understanding of when they occur during the day and during which of the four academic terms. The analysis shows that the most popular time for scheduling courses is between 9:30 am and noon for each of the four summer session terms. Given the limited number of general purpose classrooms on campus, accommodating faculty preference for rooms, buildings, and computer equipment is sometimes not possible during the most in demand course times. The results also showcase the potential for having summer courses four-day per week …

Navigating From The Local To The Cosmopolitan: Expanding The Scholarship Of Teaching And Learning Commons, Paul Savory, Amy M. Goodburn

Department of Industrial and Management Systems Engineering: Faculty Publications

This collaborative poster highlights how "Expanding‐the‐SOTL‐Commons" is composed of nine collaborating institutions from the US and Canada. Situated within the Carnegie Academy for Scholarship of Teaching and Learning’s Intuitional Leadership Program, our initiative seeks innovative ways to sustain and advance the teaching commons both on our own campuses and across the broader ISSOTL community. Our diverse group of institutions of higher education acknowledges the multiple dimensions of work that communities and individuals contribute to the scholarship of teaching and learning and recognizes that common interest reside in how individuals and institutions enter into this area of scholarship, and how they …

Flush-Mounted Steady-Periodic Heated Film With Application To Shear-Stress Measurement, Kevin D. Cole

Department of Mechanical and Materials Engineering: Faculty Publications

Surface-mounted heated films have been used for fluid-flow measurement for many years. Recently unsteady heating of such surface films has been explored experimentally. In this paper steady-periodic heating of a surface-mounted film is studied analytically. Wall effects and axial heat conduction in the fluid are included. The temperature is found as an exact integral expression constructed from separate Green’s function formulations in the fluid flow and in the solid wall that are matched at the fluid-solid interface. Results for temperature, obtained by quadrature, are reported for several flow speeds and several steady-periodic frequencies. The results show that steady-periodic heating has …

Extracellular Matrix Protein Orientation By Adsorption On Self-Assembled Monolayers Controls Nonviral Gene Delivery, Beth A. Duensing, Angela K. Pannier

Department of Agricultural and Biological Systems Engineering: Presentations and White Papers

To date, most efforts to understand and improve the efficiency of nonviral gene delivery have focused on altering the physicochemical properties of delivery systems and developing new delivery strategies. The importance of the cellular microenvironment in achieving successful nonviral gene transfer has not been thoroughly examined, though proteins of the extracellular matrix (ECM) mediate cell adhesion and serve to regulate cellular behavior that may, in turn, dictate the cellular responsiveness to nonviral gene delivery. Self-assembled monolayers (SAMs) of alkanethiols on gold were used to control adsorption of ECM molecules and thus control the architecture of the extracellular environment presented to …

Real-Time Vertical Track Deflection Measurement System, Sheng Lu

Department of Mechanical and Materials Engineering: Dissertations, Theses, and Student Research

Track quality is a major factor in railroad safety, and one accepted indicator of track quality is the vertical track deflection. Measuring track deflection from a moving railcar is difficult because there is no stable reference for the measurements. A system developed by researchers at the University of Nebraska to measure track deflection from a moving railcar in real-time is described in detail. The system consists of a loaded hopper with a camera/laser sensor system to detect the vertical deflection of the rail relative to the wheel/rail contact point. Modeling and simulation of the system is also presented along with …

An Analysis Of The Technical And Economic Potential For Mid-Scale Distributed Wind, K. Granfield, A. Kagel, A. Appleton

United States Department of Energy: Publications

This report examines the status, restrainers, drivers, and estimated development potential of mid-scale (10 kW to 5000 kW) distributed wind projects. This segment of the wind market has not enjoyed the same growth that central-station wind has experienced. The purpose of this report is to analyze why, and to assess the market potential for this technology under current market and policy conditions.

As discussed in section 2, one of the most significant barriers to the development of distributed wind is a general scarcity of turbine choices and turbine inventory available for purchase. Most turbine manufacturers have scaled back their involvement …

Contact-Resonance Atomic Force Microscopy For Viscoelasticity, P. A. Yuya, D. C. Hurley, Joseph A. Turner

Department of Engineering Mechanics: Faculty Publications

We present a quantitative method for determining the viscoelastic properties of materials with nanometer spatial resolution. The approach is based on the atomic force acoustic microscopy technique that involves the resonant frequencies of the atomic force microscopy cantilever when its tip is in contact with a sample surface. We derive expressions for the viscoelastic properties of the sample in terms of the cantilever frequency response and damping loss. We demonstrate the approach by obtaining experimental values for the storage and loss moduli of a poly(methyl methacrylate) film using a polystyrene sample as a reference material. Experimental techniques and system calibration …

Newsletters For The Larsen Tractor Museum, Tractor Museum

Lester F. Larsen Tractor Museum: Planning and Development Documents

No abstract provided.

Acuta Enews October 2008, Vol. 37, No. 10

ACUTA Newsletters

In This Issue

Nominate Now for 2009-2008 Board of Directors

From the President................. Corinne Hoch, Columbia Univ., ACUTA President

Tech Talk: Why Not Share That Extra Computing Power?................ Kevin Tanzillo, Dux PR

DC Update................. Dave Ostrom, Washington State University

Clemson Researchers' EarthBottle Made fro Plants Will Soon Be in Stores

Info Links...................... Randy Hayes, Univ. of Northern Iowa

The ICT Regulations toolkit: A Resource Worth Checking Out

Loans to Cover Disaster Losses

Board Report................ Riny Ledgerwood, San Diego State Univ., ACUTA Secretary/Treasurer

Check It Out: Press Releases... Job Postings... RFIs/RFPs

OCS Federation Submarien Cable Completed

Welcome New Members

Energy-Constrained Distortion Reduction Optimization For Wavelet-Based Coded Image Transmission In Wireless Sensor Networks, Wei Wang, Dongming Peng, Honggang Wang, Hamid Sharif, Hsiao-Hwa Chen

Department of Electrical and Computer Engineering: Faculty Publications (to 2015)

Image transmissions in Wireless Multimedia Sensor Networks (WMSNs) are often energy constrained. They also have requirement on distortion minimization, which may be achieved through Unequal Error Protection (UEP) based communication approaches. In related literature with regard to wireless multimedia transmissions, significantly different importance levels between image-pixel-position information and image-pixel-value information have not been fully exploited by existing UEP schemes. In this paper, we propose an innovative image-pixel-position information based resource allocation scheme to optimize image transmission quality with strict energy budget constraint for image applications in WMSNs, and it works by exploring these uniquely different importance levels among image data …

Engineering@Nebraska - Fall 2008

Engineering@Nebraska (Alumni Magazine)

Table of Contents:

Front & Center
A Welcome Home: Zero Net Energy Test House unites university and industry as students' learning is caught green-handed
Making their mark on mars: Huskers at Honeybee, a New York City robotics firm, work on Mars missions
Epigenetics: A dialogue between biologists and engineers: Joe Turner, professor and chair of the Department of Engineering Mechanics, collaborates with UNL plant scientist Sally McKenzie on nanoscale work with huge potential
Energy monitoring on the home front: Together with OPPD, Nebraska Engineering studies devices to promote efficiency
Wave of the future: Biological Systems Engineering professor Greg Bashford creates …

Performance Evaluation Of Safety Grates For Cross-Drainage Culverts, Karla A. Polivka, Dean L. Sicking, Robert W. Bielenberg, John R. Rohde, Ronald K. Faller, John D. Reid

Nebraska Department of Transportation: Research Reports

No abstract provided.

Impact Mechanics And High-Energy Absorbing Materials: Review, Pizhong Qiao, Mijia Yang, Florin Bobaru

Department of Engineering Mechanics: Faculty Publications

In this paper a review of impact mechanics and high-energy absorbing materials is presented. We review different theoretical models (rigid-body dynamics, elastic, shock, and plastic wave propagation, and nonclassical or nonlocal models. and computational methods (finite-element, finite-difference, and mesh-free methods. used in impact mechanics. Some recent developments in numerical simulation of impact (e.g., peridynamics) and new design concepts proposed as high energy absorbing materials (lattice and truss structures, hybrid sandwich composites, metal foams, magnetorheological fluids, porous shape memory alloys. are discussed. Recent studies on experimental evaluation and constitutive modeling of strain rate-dependent polymer matrix composites are also presented. Impact damage …

Effect Of Intermittent Applications Of Continuous Ultrasound Signal On The Morphology And Cytoskeletal Organization In Chondrocytes, Anuradha Subramanian, Sandra Noriega, Gulnara Hasanova

Anuradha Subramanian Publications

The cellular component of the articular cartilage, chondrocytes, have long been recognized as strain-sensitive cells, and have the ability to sense mechanical stimulation through surface receptors and intracellular signaling pathways. In the present study, a continuous ultrasound wave for predetermined time intervals was employed, as opposed to pulsed-ultrasound used in previous studies, to stimulate chondrocytes seeded in 3D scaffolds. Chondrocytes seeded in 3D scaffolds (n = 6) were subjected to stimulation by US as follows: 1.5 MHz for 161 s, 5.0 MHz for 51 s and 8.5 MHz for 24 s and the US signal was applied twice in a …

Control On Platelet Adhesion And Activation Events By Selective And Specific Binding Of Plasma Protein On Peptide-Coupled Surface, Anuradha Subramanian, Sanjukta Guha-Thankruta

Anuradha Subramanian Publications

Implantable material surfaces suffer from unavoidable major events of blood–biomaterial interactions leading to thrombus formation and finally foreign material rejection. An albuminated surface can minimize the platelet adhesion and activation that reduces the chance of thrombus formation. The main objective of our work was to design surfaces having maximum human serum albumin (HSA) binding capacity over other plasma proteins in blood by covalently grafting custom made peptides having selectivity and specificity towards HSA. First, silicon wafer surfaces were chemically treated to generate –NH2 terminated self-assembled monolayer (SAM). SAMs were then covalently coupled with (a) peptides using 1- ethyl-3-[3-dimethylaminopropyl]carbodiimide hydrochloride and …

Importance Of Annealing Times In The Pcr Amplification Of Gc-Rich Genes, Anuradha Subramanian, Tarlan Mamedov, Elsje Pinnear, Hendrik J. Viljoen

Anuradha Subramanian Publications

This combined theoretical and experimental study conclusively demonstrates that annealing times play a crucial role in the PCR amplification of GC-rich templates. To assist with the DNA amplification of GC-rich targets, a theory has been developed that evaluates the fraction of annealed primer/polymerase complex at the correct binding site as a function of annealing temperature and annealing period. Optimum annealing times lie in the range of 3 to 6 s, and annealing times greater than 10 s yield smeared PCR amplified products. The theory has been applied to the PCR amplification of the following human cDNA templates: ARX gene (78.2%, …

Ultraviolet And Pulsed Electric Field Treatments Have Additive Effect On Inactivation Of E. Coli In Apple Juice, T. K. Gachovska, Saurabh Kumar, Harshanardhan Thippareddi, F. Williams

P. F. (Paul Frazer) Williams Publications

Apple juice inoculated with Escherichia coli ATCC 23472 was processed continuously using either ultraviolet (UV), high-voltage pulsed electric field (PEF), or a combination of the PEF and UV treatment systems. Apple juice was pumped through either of the systems at 3 flow rates (8, 14, and 20 mL/min). E. coli was reduced by 3.46 log CFU/mL when exposed in a 50 cm length of UV treatment chamber at 8 mL/min (2.94 s treatment time with a product temperature increase of 13 °C). E. coli inactivation of 4.87 log CFU/mL was achieved with a peak electric field strength of 60 kV/cm …

Surface Magnetoelectric Effect In Ferromagnetic Metal Films, Chun-Gang Duan, Julian P. Velev, Renat F. Sabirianov, Ziqiang Zhu, Junhao Chu, Sitaram Jaswal, Evgeny Y. Tsymbal

Nebraska Center for Materials and Nanoscience: Faculty Publications

A surface magnetoelectric effect is revealed by density-functional calculations that are applied to ferromagnetic Fe(001), Ni(001), and Co(0001) films in the presence of an external electric field. The effect originates from spin-dependent screening of the electric field which leads to notable changes in the surface magnetization and the surface magnetocrystalline anisotropy. These results are of considerable interest in the area of electrically controlled magnetism and magnetoelectric phenomena.

Lester Larsen: Progress Of Tractor Test Work 1946 -1956, Tractor Museum

Individuals Associated with the Nebraska Tractor Test

When Lester F. Larsen was hired as Engineer in Charge of the Nebraska Tractor Test, the laboratory had been inactive since 1941 due to World War II. Much of the test equipment was out of order and in need of repair. He kept a journal called the Progress of Tractor Test Work. This journal of day to day activities extended from 1946 through 1956.

Description Of Versatile Optical Polarimetric Scatterometer That Measures All 16 Elements Of The Mueller Matrix For Reflection And Transmission: Application To Measurements Of Scatter Cross Sections, Ellipsometric Parameters, Optical Activity, And The Complex Chiral Parameters, Ezekiel Bahar, Robert D. Kubik

Department of Electrical and Computer Engineering: Faculty Publications

A detailed description of an optical polarimetric scatterometer, its capabilities, and special application are presented. This instrument measures the 44 Mueller matrix elements as well as bidirectional reflective distribution functions scatter cross sectionsfor light that is scattered from a target. Incident polarized light at wavelengths =0.6328 and =1.06 m can be directed toward the target in an arbitrary direction. The receiver can be located anywhere in the solid angle 4. Backscatter measurements, most commonly used in remote sensing, can also be obtained. The scatterometer has been used to validate different analytical/numerical solutions to a broad class of electromagnetic scattering problems, …

Application Of The Modified Log-Wake Law In Open-Channels, Junke Guo, Pierre Y. Julien

Department of Civil and Environmental Engineering: Faculty Publications

The modified log-wake law, which was developed for turbulent boundary layers and pipe flows, is extended to turbulent flows in open-channels. Turbulent velocity profiles in open-channels can be approximated with three components: (1) the law of the wall that results from the constant bed shear stress; (2) the law of the wake that reflects the effects of gravity, secondary currents and bed roughness; and (3) the cubic correction near the maximum velocity. A procedure to determine the four model parameters from velocity measurements while keeping κ = 0.41 is presented. The modified log-wake law compares very well with experimental data …

Acuta Enews September 2008, Vol. 37, No. 9

ACUTA Newsletters

In This lssue

From ACUTA Headquarters: Ramped-up Schedule................Jeri A. Semer, CAE, Executive Director

New Section on ACUTA Website

Audio Seminar: Technology-Related lmptications of the 2008 Higher Ed Opportunities Act

Tech Talk: ACUTA Member Schools Are Mostly in the Green ........ Kevin Tanzillo, Dux PR

DC Update ......... Dave Ostrom, Washington State University

lP PBX Witt Reign: Converged PBX Will Slowly Fade Away........................Gary Audin, Delphi, lnc.

Get Your ACUTA Logo here

Look on the Light Side

lnfo Links ............. Randy Hayes, Univ. of Northern lowa

Welcome New Members

Check lt Out: RFls/RFPs, Job Postings, Press Releases

Finite Element Analysis Using Nonconforming Mesh, Ashok V. Kumar, Ravi Buria, Sanjeev Padmanabhan, Linxia Gu

Department of Mechanical and Materials Engineering: Faculty Publications

A method for finite element analysis using a regular or structured grid is described that eliminates the need for generating conforming mesh for the geometry. The geometry of the domain is represented using implicit equations, which can be generated from traditional solid models. Solution structures are constructed using implicit equations such that the essential boundary conditions are satisfied exactly. This approach is used to solve boundary value problems arising in thermal and structural analysis. Convergence analysis is performed for several numerical examples and the results are compared with analytical and finite element analysis solutions to show that the method gives …