Engineering Commons^™

Efficiency Of Gene Silencing In Arabidopsis: Direct Inverted Repeats Vs. Transitive Rnai Vectors, Sergei A. Filichkin, Stephen P. Difazio, Amy M. Brunner, John M. Davis, Zamin K. Yang, Udaya C. Kalluri, Renee S. Arias, Elizabeth Etherington, Gerald A. Tuskan, Steven H. Strauss

United States Department of Energy: Publications

We investigated the efficiency of RNA interference (RNAi) in Arabidopsis using transitive and homologous inverted repeat (hIR) vectors. hIR constructs carry self-complementary intron-spliced fragments of the target gene whereas transitive vectors have the target sequence fragment adjacent to an intron-spliced, inverted repeat of heterologous origin. Both transitive and hIR constructs facilitated specific and heritable silencing in the three genes studied (AP1 , ETTIN and TTG1 ). Both types of vectors produced a phenotypic series that phenocopied reduction of function mutants for the respective target gene. The hIR yielded up to fourfold higher proportions of events with strongly manifested reduction …

Phosphate Imposed Limitations On Biological Reduction And Alteration Of Ferrihydrite, Thomas Borch, Yoko Masue, Ravi K. Kukkadapu, Scott Fendorf

United States Department of Energy: Publications

Biogeochemical transformation (inclusive of dissolution) of iron (hydr)oxides resulting from dissimilatory reduction has a pronounced impact on the fate and transport of nutrients and contaminants in subsurface environments. Despite the reactivity noted for pristine (unreacted) minerals, iron (hydr)oxides within native environments will likely have a different reactivity owing in part to changes in surface composition. Accordingly, here we explore the impact of surface modifications induced by phosphate adsorption on ferrihydrite reduction by Shewanella putrefaciens under static and advective flow conditions. Alterations in surface reactivity induced by phosphate changes the extent, decreasing Fe(III) reduction nearly linearly with increasing P surface coverage, …

Reduction Of Pertechnetate [Tc(Vii)] By Aqueous Fe(Ii) And The Nature Of Solid Phase Redox Products, John M. Zachara, Steve M. Heald, Byong-Hun Jeon, Ravi K. Kukkadapu, Chongxuan Liu, James P. Mckinley, Alice C. Dohnalkova, Dean A. Moore

United States Department of Energy: Publications

The subsurface behaviour of ⁹⁹Tc, a contaminant resulting from nuclear fuels reprocessing, is dependent on its valence (e.g., IV or VII). Abiotic reduction of soluble Tc(VII) by Fe(II)_(aq) in pH 6–8 solutions was investigated under strictly anoxic conditions using an oxygen trap (<7.5 · 10^-9 atm O₂). The reduction kinetics were strongly pH dependent. Complete and rapid reduction of Tc(VII) to a precipitated Fe/Tc(IV) form was observed when 11 µmol/L of Tc(VII) was reacted with 0.4 mmol/L Fe(II) at pH 7.0 and 8.0, while no significant reduction was observed over 1 month at pH 6.0. Experiments conducted …

Biostimulation Of Iron Reduction And Subsequent Oxidation Of Sediment Containing Fe-Silicates And Fe-Oxides: Effect Of Redox Cycling On Fe(Iii) Bioreduction, John Komlos, Ravi K. Kukkadapu, John M. Zachara, Peter R. Jaffe

United States Department of Energy: Publications

Sediment containing a mixture of iron (Fe)-phases, including Fe-oxides (mostly Al-goethite) and Fe-silicates (illites and vermiculite) was bioreduced in a long-term flow through column experiment followed by re-oxidation with dissolved oxygen. The objective of this study was (a) to determine the nature of the re-oxidized Fe(III), and (b) to determine how redox cycling of Fe would affect subsequent Fe(III)-bioavailability. In addition, the effect of Mn on Fe(III) reduction was explored.⁵⁷Fe-Mössbauer spectroscopy measurements showed that biostimulation resulted in partial reduction (20%) of silicate Fe(III) to silicate Fe(II) while the reduction of goethite was negligible. Furthermore, the reduction of Fe …

Influence Of Calcium On Microbial Reduction Of Solid Phase Uranium(Vi), Chongxuan Liu, Byong-Hun Jeon, John M. Zachara, Zheming Wang

United States Department of Energy: Publications

The effect of calcium on the dissolution and microbial reduction of a representative solid phase uranyl [U(VI)], sodium boltwoodite (NaUO₂SiO₃OH •1.5H₂O), was investigated to evaluate the rate-limiting step of microbial reduction of the solid phase U(VI). Microbial reduction experiments were performed in a culture of a dissimilatory metal-reducing bacterium (DMRB), Shewanella oneidensis strain MR-1, in a bicarbonate medium with lactate as electron donor at pH 6.8 buffered with PIPES. Calcium increased the rate of Na-boltwoodite dissolution and U(VI) bioavailability by increasing its solubility through the formation of a ternary aqueous calcium-uranyl-carbonate species. The ternary …

Spectroscopic Evidence For Uranium Bearing Precipitates In Vadose Zone Sediments At The Hanford 300-Area Site, Yuji Arai, M. A. Marcus, N. Tamura, J. A. Davis, John M. Zachara

United States Department of Energy: Publications

Uranium (U) solid-state speciation in vadose zone sediments collected beneath the former North Process Pond (NPP) in the 300 Area of the Hanford site (Washington) was investigated using multi-scale techniques. In 30 day batch experiments, only a small fraction of total U (~7.4%) was released to artificial groundwater solutions equilibrated with1% pCO₂. Synchrotron-based micro-X-ray fluorescence spectroscopy analyses showed that U was distributed among at least two types of species: (i) U discrete grains associated with Cu and (ii) areas with intermediate U concentrations on grains and grain coatings. Metatorbernite (Cu[UO₂]₂[PO₄]₂•8H …

Cation Exchange Reactions Controlling Desorption Of 90sr2+ From Coarse-Grained Contaminated Sediments At The Hanford Site, Washington, James Mckinley, John M. Zachara, Steven Smith, Chongxuan Liu

United States Department of Energy: Publications

Nuclear waste that bore ⁹⁰Sr²⁺ was accidentally leaked into the vadose zone at the Hanford site, and was immobilized at relatively shallow depths in sediments containing little apparent clay or silt-sized components. Sr²⁺, ⁹⁰Sr²⁺, Mg2+, and Ca²⁺ was desorbed and total inorganic carbon concentration was monitored during the equilibration of this sediment with varying concentrations of Na⁺, Ca²⁺. A cation exchange model previously developed for similar sediments was applied to these results as a predictor of final solution compositions. The model included binary exchange reactions for the four …

Geochemical Processes Controlling Migration Of Tank Wastes In Hanford’S Vadose Zone, John M. Zachara, Jeff Serne, Mark Freshley, Fred Mann, Frank Anderson, Marcus Wood, Tom Jones, Dave Myers

United States Department of Energy: Publications

Nuclear wastes from Hanford’s processing for separation of plutonium are stored in massive, buried, single-shell tanks in 18 tank farms. These so-called tank wastes were initially thermally hot because of radioactive decay, and many exhibited extreme chemical character in terms of pH, salinity, and radionuclide concentration. At present, 67 of the 149 single shell tanks are suspected to have released over 1.9 million L of tank waste to the vadose zone, with most leak events occurring between 1950 and 1975. Boreholes have been placed through the largest vadose zone plumes to define the extent of contaminant migration and to develop …

Generation Of Electron Bunches At Low Repetition Rates Using A Beat-Frequency Technique, M. Poelker, J. Grames, J. Hansknecht, R. Kazimi, J. Musson

United States Department of Energy: Publications

Even at a continuous wave facility such as CEBAF at Jefferson Lab, an electron beam with long time intervals (tens of ns) between individual bunches can be useful, for example, to isolate sources of background via time of flight detection or to measure the energy of neutral particles that cannot be separated with a magnetic field. This paper describes a demonstrated method to quickly and easily deliver bunches with repetition rates of 20 to 100 MHz corresponding to time intervals between 50 and 10 ns (respectively). This is accomplished by changing the ON/OFF frequency of the photogun drive laser by …

Small Wind Electric Systems: A Nebraska Consumer’S Guide

United States Department of Energy: Publications

Can I use wind energy to power my home? This question is being asked across the country as more people look for affordable and reliable sources of electricity. Small wind electric systems can make a significant contribution to our nation’s energy needs. Although wind turbines large enough to provide a significant portion of the electricity needed by the average U.S. home generally require one acre of property or more, approximately 21 million U.S. homes are built on one-acre and larger sites, and 24% of the U.S. population lives in rural areas.

A small wind electric system will work for you …

Valuing Water Quality Improvements In The United States Using Meta-Analysis: Is The Glass Half-Full Or Half-Empty For National Policy Analysis?, George Van Houtven, John Powers, Subhrendu K. Pattanayak

United States Environmental Protection Agency: Publications

The literature estimating the economic value for water quality changes has grown considerably over the last 30 years, resulting in an expanded pool of information potentially available to support national and regional policy analysis. Using 131 willingness to pay estimates from 18 studies that use a similar definition of water quality, we performed a meta-regression analysis and found mixed results. We find that WTP varies in systematic and expected ways with respect to factors such as the size of the water quality changes, average household income, and use/nonuse characteristics of respondents. As a whole, we conclude that our metaregression results …

Nebraska Summary: S589 Agco Rt165a, Nebraska Tractor Test Lab

Nebraska Tractor Tests

ABOUT THE TEST REPORT AND USE OF THE DATA The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data. EXPLANATION OF THE TEST PROCEDURES Purpose The purpose of …

Dynamic Impact Testing Of W152x13.4 (W6x9) Steel Posts On A 2:1 Slope, Gopi Dey, Ronald K. Faller, John A. Hascall, Robert W. Bielenberg, Karla A. Polivka, Kirk Molacek

Mid-America Transportation Center: Final Reports and Technical Briefs

Dynamic impact testing of W152x13.4 (W6x9) steel posts at various embedment depths has been detailed, and the results stated. A total of 17 bogie tests have been performed on a 2:1 slope, with post lengths varying from 1,829 mm (6 ft) through 2,743 mm (9 ft). A total of four bogie tests were performed on level terrain using 1,829-mm (6-ft) long steel posts at two different impact speeds. For each bogie test, raw acceleration data, obtained from accelerometers, was filtered and then force-displacement and energy-displacement graphs were plotted. From the energy-displacement graphs, the average post-soil forces were calculated for a …

Pairwise Cobalt Doping Of Boron Carbides With Cobaltocene, A. Yu. Ignatov, Yaroslav B. Losovyj, L. Carlson, D. Lagraffe, Jennifer I. Brand, Peter A. Dowben

Materials Research Science and Engineering Center: Faculty Publications

We have performed Co K-edge x-ray absorption fine structure and x-ray absorption near edge structure measurements of Co-doped plasma enhanced chemical vapor phase deposition (PECVD) grown “C₂B₁₀H_x” semiconducting boron carbides, using cobaltocene. Cobalt does not dope PECVD grown boron carbides as a random fragment of the cobaltocene source gas. The Co atoms are fivefold boron coordinated (R=2.10±0.02 Å) and are chemically bonded to the icosahedral cages of B₁₀CH_x or B₉C₂H_y. Pairwise Co doping occurs, with the cobalt atoms favoring sites some 5.28±0.02 …

Cluster-Assembled Iron-Platinum Nanocomposite Permanent Magnets, Xiangxin Rui, Zhiguang Sun, Yinfan Xu, David J. Sellmyer, Jeffrey E. Shield

Materials Research Science and Engineering Center: Faculty Publications

Exchange-spring nanocomposite permanent magnets have received a great deal of attention for their potential for improved the energy products. Predicted results, however, has been elusive. Optimal properties rely on a uniformly fine nanostructure. Particularly, the soft magnetic phase must be below approximately 10 nm to ensure complete exchange coupling. Inert gas condensation (IGC) is an ideal processing route to produce sub-10 nm clusters method. Two distinct nanostructures have been produced. In the first, Fe clusters were embedded in an FePt matrix by alternate deposition from two sources. Fe cluster content ranged from 0 to 30 volume percent. Post-deposition multi-step heat …

United States Patent Application Publication: System And Method For Sequence Distance Measure For Phylogenetic Tree Construction, K. Sayood, Hasan H. Otu, Steven H. Hinrichs

Department of Electrical and Computer Engineering: Faculty Publications

The present invention permits identification of biological materials following recovery of DNA using standard techniques by comparing a mathematical characterization of the unknown sequence with the mathematical characterization of DNA sequences of known genera and species. The clinical identification of infectious organisms is required for accurate diagnosis and selection of antimicrobial therapeutics. The invention allows an ab initio approach with the potential for rapid identification of biological materials of unknown origin. The approach provides for identification and classification of emergent or new organisms without previous phenotypic identification. The technique may also be used in monitoring situations where the need exists …

Cell Bank Characterization And Fermentation Optimization For Production Of Recombinant Heavy Chain C-Terminal Fragment Of Botulinum Neurotoxin Serotype E (Rbonte(HC): Antigen E) By Pichia Pastoris, Jayanta Sinha, Mehmet Inan, Sarah Fanders, Shinichi Taoka, Mark Gouthro, Todd Swanson, Rick Barent, Ardis Barthuli, Bonnie M. Loveless, Leonard A. Smith, Theresa Smith, Ian Henderson, John Ross, Michael M. Meagher

Papers in Biochemical Engineering

A process was developed for production of a candidate vaccine antigen, recombinant C-terminal heavy chain fragment of the botulinum neurotoxin serotype E, rBoNTE(H_c)in Pichia pastoris. P. pastoris strain GS115 was transformed with the rBoNTE(H_c) gene inserted into pHILD4 Escherichia coli—P. pastoris shuttle plasmid. The clone was characterized for genetic stability, copy number, and BoNTE(H_c) sequence. Expression of rBoNTE(H_c) from the Mut⁺ HIS4 clone was confirmed in the shake-flask, prior to developing a fed-batch fermentation process at 5 and 19 L scale. The fermentation process consists of a glycerol growth phase in …

Work In Progress - Increasing Transfer Student Enrollment, Retention And Graduation Through The Strengthening Transitions Into Engineering Programs, Stephanie G. Adams, Lance C. Pérez, John J. Ballard

Department of Electrical and Computer Engineering: Faculty Publications

Large populations of students are matriculating to community colleges (CC). However, transferring from a CC to 4-year undergraduate engineering degree program is often quite difficult. There are few, if any, engineering courses offered at the CCs. In addition, long prerequisite chains reduce many transfer students to Freshman or Sophomore status, even though they have had two years of post-secondary education. The University of Nebraska-Lincoln (UNL), Strengthening Transitions into Engineering Programs (STEP) is a program designed to facilitate the transfer of CC students to undergraduate baccalaureate engineering degree programs. The program consists of four engineering courses taught at the CCs with …

Quasi-Orthogonal Space-Time-Frequency Codes In Mb-Ofdm Uwb Communications, L. C. Tran, A. Mertins, Tadeusz A. Wysocki

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

The paper examines the implementation of Quasi-Orthogonal Space-Time-Frequency Codes (QOSTFCs) to increase data rates and error performance in recently proposed STFC Multiband OFDM Ultra Wideband (MB-OFDM UWB) communications systems. It is shown that, an order-4 QOSTFC not only can provide the full rate, but also may provide significantly better error performance, compared to the conventional MB-OFDM (without STFCs), and considerably better error performance, compared to order-4, orthogonal STFC MBOFDM, without increasing the total transmission power.

Design Of A 1.8v 8-Bit 500msps Folding-Interpolation Cmos A/D Converter With A Folder Averaging Technique, Dongjin Lee, Jaewon Song, Jongha Shin, Sanghoon Hwang, Minkyu Song, Tad Wysocki

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

In this paper, a CMOS analog-to-digital converter (ADC) with an 8-bit 500MSPS at 1.8V is designed. The architecture of the proposed ADC is based on a Folding ADC with a cascaded-folding and a cascaded-interpolation structure. A self-linearized preamplifier with source degeneration technique and a folder averaging technique for the high-performance are introduced. Further, a novel auto-switching encoder is also proposed. The chip has been fabricated with 0.18μm 1-poly 5-metal CMOS technology. The active chip area is 0.79mm² and it consumes about 200mW at 1.8V power supply. The DNL and INL are within ±0.6/±0.6LSB, respectively. The measured result of SNDR …

A Dendroclimatic Record Of Paleoclimate Of The Last 10,000 Years, Glacier Bay National Park And Preserve: Progress Understanding Climate Change In Southeast Alaska, Daniel Lawson, Greg Wiles, David Finnegan

United States Army: Publications

Our investigations in 2007 focused on continuing collection and analyses of tree rings from living trees and building a long ring-width series from interstadial wood. These interstadial forests were extensive and their preservation, although discontinuous and fragmented, is remarkable. In situ stumps, still rooted in growth position, and logs held within sediments remain from forests that existed at various times between glaciations over approximately the last 10,000 years.
We have analyzed previous and new collections of ring-width tree-ring series, including a multiple species collection from near Excursion Ridge in the southeast portion of the Park. These tree-ring series have a …

Electron Effective Mass And Phonon Modes In Gaas Incorporating Boron And Indium, Tino Hofmann, Mathias Schubert, G. Leibiger, V. Gottschalch

Materials Research Science and Engineering Center: Faculty Publications

The strain-free boron- and indium-containing GaAs compounds are promising candidates for III-V semiconductor solar cell absorber materials with lattice match to GaAs, for which experimental data of the electronic band structure are widely unknown. For nondegenerate, silicon-doped, n-type B_0.03In_0.06Ga_0.91As with band-gap energy of 1.36 eV, determined by near-infrared ellipsometry, a strong increase of the electron effective mass of 44% in B0.03In0.06Ga0.91As compared to In_0.06Ga_0.94As is obtained from far-infrared magneto-optic generalized ellipsometry studies. The authors thereby obtain the vibrational lattice mode behavior. For BAs, an experimentally obscure compound, the curvature …

Acuta Enews January 2007, Vol. 36, No. 1

ACUTA Newsletters

In This Issue

From ACUTA Headquarters........... Jeri A. Semer, CAE, ACUTA Executive Director

Centrex Conversion to PBX.............. Ron Walczak, Walczak Technology Consultants

Tech Talk: Duduplication Reduces Storage Needs............. Kevin Tanzillo, Dux PR

DC Update............... Jeanne Jansenius, Sewanee, The University of the South

ACUTA Alert: Federal Rules Governing Destruction of Electronically Stored Information

FYI: Useful Information from the Campus.............. Student Monitor

Setting Priorities............... Geoff Tritsch, Vantage Technology Consulting Group

Web Tip: Members Post Job Openings........... Aaron Fuehrer, ACUTA Information Technology Manager

Board Report............... Riny Ledgerwood, San Diego State Univ. of Northern Iowa

Thanks to Sponsors for 2006

A Moment in Time: …

Campus Communications Systems: Converging Technologies, The Association For Communications Technology Professionals In Higher Education

ACUTA: Other Publications

This book is a rewrite of Campus Telecommunications Systems: Managing Change, a book that was written by ACUTA in 1995. In the past decade, our industry has experienced a thousand-fold increase in data rates as we migrated from 10 megabit links (10 million bits per second) to 10 gigabit links (10 billion bits per second), we have seen the National Telecommunications Policy completely revamped; we have seen the combination of voice, data, and video onto one network; and we have seen many of our service providers merge into larger corporations able to offer more diverse services. When this book was …

Input-Output And Hybrid Techniques For Real-Time Prediction Of Delay And Maximum Queue Length At Signalized Intersections, Anuj Sharma, Darcy M. Bullock, James A. Bonneson

Department of Civil and Environmental Engineering: Faculty Publications

Vehicle delay and queue length are quantitative measures of intersection performance. The technological advancement in the field of vehicle sensors and traffic controllers has reached a point where it has enabled efficient measurement of these performance measures. Two techniques are presented for real-time measurement of vehicle delay and queue length at a signalized Intersection, and these automated delay and queue estimates are compared with manually ground-truthed measurement. These techniques were evaluated at an instrumented intersection in Noblesville, Indiana. The root-mean-square error by both techniques was below 0.7 veh-s for-estimation of average delay and less than 0.15 vehicle for estimation of …

Nebraska Blueprint - Winter 2006-07

Nebraska Blueprint (Student Publication)

Table of Contents:

Good for Livestock, Good for the Earth By Michaela McBride
Ethanol Isn’t the Fuel of the Future Editorial by Aaron Holmberg
Ethanol: The Most Viable Alternative Fuel Editorial By Frank Pribyl
Wind Energy: A Global Perspective By Khoa Chu
UNL Should Embrace Energy- Effi cient Buildings By Leila Knowles and Jeremy Emerson
Biodiesel: A Viable Alternative By Brian Neilson
On the Road Again with BioWillie By Brian Neilson
Attitude Adjustment By Aaron Holmberg

Details And Description Of Operations Research, Paul Savory

Department of Industrial and Management Systems Engineering: Reports

The ambiguous term operations research was coined during World War II. A frequent substitute is management science. Operations research is a scientific approach to analyzing problems and making decisions. It uses mathematics and mathematical modeling on computers to forecast the implications of various choices and zero in on the best alternatives. This content paper provides an overview of operations research. It highlights operations research problems, methods for solving problems, different areas of operations research, and example problems.

Peer Review Of Teaching Project: Overview Newsletter, Paul Savory, Amy M. Goodburn, Amy Nelson Burnett

Department of Industrial and Management Systems Engineering: Reports

The Peer Review of Teaching Project (PRTP) is a UNL campus program that supports teams of faculty in making visible the serious intellectual work of teaching. Begun in 1994, the project uses the same process one would use to explore a research question by having faculty inquire, analyze, and document their teaching practices and the resulting student learning and then make these results accessible for use, review, and assessment by one’s peers. The project consists of a first-year fellowship program and an advanced scholar program. Specific faculty outcomes from participating in the project include: (1) Reflecting upon, developing, and writing …

Pre/Post Assessment Of Abilities, Paul Savory

Department of Industrial and Management Systems Engineering: Instructional Materials

One approach to assess if students are learning in a course is to conduct a pre-test, post-test assessment of the course material. By comparing the two results, one can make an assessment of the knowledge learned in the course. For certain types of courses, it can be a challenge in defining an assessment instrument that measure student knowledge. This example is one I have developed for my IMSE 440/840 (Discrete Event Computer Simulation) course. Students are asked rate their ability for key course objectives defined on the course syllabus. I administer it on the first day of the course and …

A Bayesian Multilevel Modeling Approach For Data Query In Wireless Sensor Networks, Honggang Wang, Hua Fang, Kimberly A. Espy, Dongming Peng, Hamid Sharif

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

In power-limited Wireless Sensor Network (WSN), it is important to reduce the communication load in order to achieve energy savings. This paper applies a novel statistic method to estimate the parameters based on the real-time data measured by local sensors. Instead of transmitting large real-time data, we proposed to transmit the small amount of dynamic parameters by exploiting both temporal and spatial correlation within and between sensor clusters. The temporal correlation is built on the level-1 Bayesian model at each sensor to predict local readings. Each local sensor transmits their local parameters learned from historical measurement data to their cluster …