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Structure And Properties Of Ultrafine Silk Fibers Produced By Theriodopteryx Ephemeraeformis, Narendra Reddy, Yiqi Yang

Department of Textiles, Merchandising and Fashion Design: Faculty Publications

Theriodopteryx ephemeraeformis commonly known as bag worms produce ultrafine silk fibers that are remarkably different than the common domesticated (Bombyx mori) and wild (Saturniidae) silk fibers. Bag worms are considered as pests and commonly infect trees and shrubs. Although it has been known that the cocoons (bags) produced by bag worms are composed of silk, the structure and properties of the silk fibers in the bag worm cocoons have not been studied. In this research, the composition, morphology, physical structure, thermal stability, and tensile properties of silk fibers produced by bag worms were studied. Bag worm …

Missouri River Recovery Program Emergent Sandbar Habitat Complexes In The Missouri River, Nebraska And South Dakota, Draft Project Implementation Report (Pir) With Integrated Environmental Assessment

United States Army Corps of Engineers, Omaha District

The Missouri River Recovery Program (MRRP) was developed to address actions included in the U.S. Fish & Wildlife Service (USFWS) 2000 and 2003 Amended Biological Opinions (BiOp) on the Operation of the Missouri River System and the Missouri River Bank Stabilization and Navigation Fish and Wildlife Mitigation Project (Mitigation Project) authorized by the Water Resources Development Acts of 1986 and 1999 (WRDA86 and WRDA99). The BiOp and Mitigation Project provide authority and direction to complete projects for fish and wildlife habitat along Missouri River. These actions are being undertaken to address endangered species needs and mitigate for the loss of …

Missouri River Recovery Program: Integrated Science Program General Science Questions & Key Findings

United States Army Corps of Engineers, Omaha District

I.

What is the population of pallid sturgeon in the Missouri River and its tributaries? .....5
1. What are the population trends over time? ...........................5

II.

Is propagation a viable short-term solution to augment pallid sturgeon populations?
2. Can pallid sturgeon be propagated?......................................6
3. Will stocked fish survive in the river? .....................................6
4. Will stocked fish spawn in the river?........................................7
5. What is the appropriate level of stocking?................................7

III.

Do pallid sturgeon spawn in the Missouri River? ..........................7
6. Where are the locations of spawning sites? .............................7
7. What is the timing of the spawn?...........................................8
8. What are the cues …

Draft Programmatic Environmental Impact Statement For The Mechanical Creation And Maintenance Of Emergent Sandbar Habitat In The Riverine Segments Of The Upper Missouri River, Vol. 1 And 2

United States Army Corps of Engineers, Omaha District

This Draft Programmatic Environmental Impact Statement (PEIS) analyzes the potential environmental consequences of implementing the Emergent Sandbar Habitat (ESH) program on the Upper Missouri River. The purpose of the ESH program is to support least tern and piping plover populations on the Missouri River by supplementing natural habitat through the mechanical creation and replacement of ESH. The PEIS allows the public, cooperating agencies (the U.S. Fish and Wildlife Service (USFWS) and the National Park Service (NPS)), and Corps decision makers to compare impacts among a range of alternatives. The PEIS is meant to inform the selection of a preferred alternative …

Missouri River Recovery Program Sandy Point Bend Shallow Water Habitat Construction Project Draft Project Implementation Report May 2010

United States Army Corps of Engineers, Omaha District

The Missouri River Recovery Program (MRRP) was developed by the U.S. Army Corps of Engineers, Omaha District (Corps) to address actions included in the 2000 and 2003 Amended Biological Opinions (BiOp) on the Operation of the Missouri River System and the Missouri River Bank Stabilization and Navigation Fish and Wildlife Mitigation Project (Mitigation Project) authorized by the Water Resources Development Acts of 1986 and 1999 (WRDA86 and WRDA99). The BiOp and Mitigation Project provide direction and authority to complete projects that provide fish and wildlife habitat along Missouri River. These actions are being undertaken to address endangered species needs and …

Donor Payoffs And Other-Regarding Preferences In Cotton-Top Tamarins (Saguinus Oedipus), Jeffrey R. Stevens

Department of Psychology: Faculty Publications

Helping others at no cost to oneself is a simple way to demonstrate other-regarding preferences. Yet, primates exhibit mixed results for other-regarding preferences: chimpanzees and tamarins do not show these effects, whereas capuchin monkeys and marmosets preferentially give food to others. One factor of relevance to this no-cost food donation is the payoff to the donor. Though donors always receive the same payoffs regardless of their choice, previous work varies in whether they receive either a food reward or no food reward. Here, I tested cotton-top tamarins in a preferential giving task. Subjects could choose from two tools, one of …

The Adaptive Nature Of Impulsivity, Jeffrey R. Stevens, David W. Stephens

Department of Psychology: Faculty Publications

An old joke circulates among animal behavior instructors. One can, the joke goes, divide the topics of animal behavior into four Fs: fighting, fleeing, feeding, and reproduction. This somewhat tired joke carries considerable truth. Animals behaving in nature surely must make decisions about conflicts, predator avoidance, feeding, and mating. Male crickets, for example, are notoriously combative. Studies have shown, however, that they escalate fights in some situations and retreat to fight another day in others (Beaugrand, 1997; Parker, 1974; Parker & Rubenstein, 1981). Squirrels, like many small animals, respond to the presence or absence of protective cover; for example, they …

Regulation Of Space Activities In The Netherlands: From Hugo Grotius To The High Ground Of Outer Space, Frans G. Von Der Dunk

Space, Cyber, and Telecommunications Law Program: Faculty Publications

The Netherlands, being aware of its relative size when compared to the major spacefaring nations not only globally but also in the European context, has always addressed outer space and space activities from the perspective of the role it could feasibly play. It has thus concentrated on a few niche areas which were either closely aligned to existing capabilities and experience or seemed to offer possibilities for mid-size economies and societies to play an important role.

The longstanding focus on scientific/technical aspects of space activities on the one hand, and on an international/legal context for them on the other, constitutes …

Vowel Recognition From Continuous Articulatory Movements For Speaker-Dependent Applications, Jun Wang, Jordan R. Green, Ashok Samal, Tom D. Carrell

Department of Special Education and Communication Disorders: Faculty Publications

A novel approach was developed to recognize vowels from continuous tongue and lip movements. Vowels were classified based on movement patterns (rather than on derived articulatory features, e.g., lip opening) using a machine learning approach. Recognition accuracy on a single-speaker dataset was 94.02% with a very short latency. Recognition accuracy was better for high vowels than for low vowels. This finding parallels previous empirical findings on tongue movements during vowels. The recognition algorithm was then used to drive an articulation-to-acoustics synthesizer. The synthesizer recognizes vowels from continuous input stream of tongue and lip movements and plays the corresponding sound samples …

Orostiff: Face-Referenced Measurement Of Perioral Stiffness In Health And Disease, Shin-Ying Chu, Steven M. Barlow, Douglas Kieweg, Jaehoon Lee

Department of Special Education and Communication Disorders: Faculty Publications

A new device and automated measurement technology known as OroSTIFF is described to characterize non-participatory perioral stiffness in healthy adults for eventual application to patients with orofacial movement disorders associated with neuromotor disease, traumatic injury, or congenital clefts of the upper lip. Previous studies of perioral biomechanics required head stabilization for extended periods of time during measurement which precluded sampling patients with involuntary body/head movements (dyskinesias), or pediatric subjects. The OroSTIFF device is face-referenced and avoids the complications associated with head-restraint. Supporting data of non-participatory perioral tissue stiffness using OroSTIFF are included from 10 male and 10 female healthy subjects. …

Secure Communication Over Fading Channels With Statistical Qos Constraints, Deli Qiao, M. Cenk Gursoy, Senem Velipasalar

Department of Electrical and Computer Engineering: Faculty Publications

In this paper, secure transmission of information over an ergodic fading channel is studied in the presence of statistical quality of service (QoS) constraints.We employ effective capacity to measure the secure throughput of the system, i.e., effective secure throughput. We assume that the channel side information (CSI) of the main and the eavesdropper channels is available at the transmitter side. Under this assumption, we investigate the optimal power control policies that maximize the effective secure throughput. In particular, it is noted that opportunistic transmission is no longer optimal and the transmitter should not wait to send the data at …

An Examination Of Autism Spectrum Disorders In Relation To Human Evolution And Life History Theory, Daniel E. Lomelin

Nebraska Anthropologist

Autism and Autism Spectrum Disorders are multifaceted conditions that are being diagnosed increasingly in Western nations. Current research suggests genetic and epigenetic effects as well as social and environmental conditions all playing direct roles in the expression and development of these disorders. Evaluating the development of the human brain s increased intelligence and plasticity in terms of human life history and evolutionary trade offs allows for new hypotheses to be formed regarding the development of the disorders. Aspects of the broad autism phenotype may have given ancient humans advantages in tool making and mechanical thinking, thus preserving the trait in …

A Noncooperative Power Control Game In Multiple-Access Fading Channels With Qos Constraints, Deli Qiao, M. Cenk Gursoy, Senem Velipasalar

Department of Electrical and Computer Engineering: Faculty Publications

In this paper, a game-theoretic analysis for the resource allocation policies in fading multiple-access channels (MAC) in the presence of quality of service (QoS) constraints is performed. Effective capacity, which provides the maximum constant arrival rate, or throughput, that a given service process can support while satisfying statistical delay constraints, is considered in a multiuser scenario. We assume that the channel side information (CSI) is available at both the receiver and transmitters, and the transmitters are selfish, rational with certain QoS constraints and average power limitations. Without the aid of the receiver, we prove that there is always a unique …

About The Authors

Honors in Practice Online Archive

No abstract provided.

A Grammar-Based Distance Metric Enables Fast And Accurate Clustering Of Large Sets Of 16s Sequences, David J. Russell, Samuel F. Way, Andrew K. Benson, Khalid Sayood

Department of Electrical and Computer Engineering: Faculty Publications

Background: We propose a sequence clustering algorithm and compare the partition quality and execution time of the proposed algorithm with those of a popular existing algorithm. The proposed clustering algorithm uses a grammar-based distance metric to determine partitioning for a set of biological sequences. The algorithm performs clustering in which new sequences are compared with cluster-representative sequences to determine membership. If comparison fails to identify a suitable cluster, a new cluster is created.

Results: The performance of the proposed algorithm is validated via comparison to the popular DNA/RNA sequence clustering approach, CD-HIT-EST, and to the recently developed algorithm, …

Mechanical Sensorless Maximum Power Tracking Control For Direct-Drive Pmsg Wind Turbines, Xu Yang, Xiang Gong, Wei Qiao

Department of Electrical and Computer Engineering: Faculty Publications

Wind turbine generators (WTGs) are usually equipped with mechanical sensors to measure wind speed and rotor position for system control, monitoring, and protection. The use of mechanical sensors increases the cost and hardware complexity and reduces the reliability of the WTG systems. This paper proposes a mechanical sensorless maximum power tracking control for wind turbines directly driving permanent magnetic synchronous generators (PMSGs). In the proposed algorithm, the PMSG rotor position is estimated from the measured stator voltages and currents by using a sliding mode observer (SMO). The wind turbine shaft speed is estimated from the PMSG back electromotive force (EMF) …

Studies Of Dynamic Crack Propagation And Crack Branching With Peridynamics, Youn Doh Ha, Florin Bobaru

Department of Engineering Mechanics: Faculty Publications

In this paper we discuss the peridynamic analysis of dynamic crack branching in brittle materials and show results of convergence studies under uniform grid refinement (m-convergence) and under decreasing the peridynamic horizon (δ-convergence). Comparisons with experimentally obtained values are made for the crack-tip propagation speed with three different peridynamic horizons.We also analyze the influence of the particular shape of themicro-modulus function and of different materials (Duran 50 glass and soda-lime glass) on the crack propagation behavior. We show that the peridynamic solution for this problem captures all the main features, observed experimentally, of dynamic crack propagation and branching, as well …

Evaluation Of Biological Cell Properties Using Dynamic Indentation Measurement, Guoxin Cao, Namas Chandra

Department of Engineering Mechanics: Faculty Publications

Viscoelastic mechanical properties of biological cells are commonly measured using atomic force microscope (AFM) dynamic indentation with spherical tips. A semiempirical analysis based on numerical simulation is built to determine the cell mechanical properties. It is shown that the existing analysis cannot reflect the accurate values of cell elastic/dynamic modulus due to the effects of substrate, indenter tip size, and cell size. Among these factors, substrate not only increases the true contact radius but also interferes the indentation stress field, which can cause the overestimation of cell moduli. Typically, the substrate effect is much stronger than the other two influences …

Dynamics Of Fibrillar Precursors Of Shishes As A Function Of Stress, Luigi Balzano, Dario Cavallo, Tim B. Van Erp, Zhe Ma, Jan-Willem Housmans, Lucia Fernandez-Ballester, Gerrit W. M. Peters

Department of Engineering Mechanics: Faculty Publications

Shishes are fibrillar crystallites that can be created by deforming a polymer melt. The formation of shishes takes place when flow is strong enough to stretch molecules. In the early stages, bundles of stretched molecules with pre-crystalline order form metastable precursors whose stability depends on their size and, hence, on the stress level. We find that for a specific isotactic polypropylene, close to the nominal melting point, a stress larger than 0.10 MPa leads to stable fibrillar precursors that are partially crystalline immediately after flow. On the other hand, below 0.10 MPa, the aspect ratio of precursors tends to unity …

Current Status And Future Directions Of Precision Aerial Application For Site-Specific Crop Management In The Usa, Yubin Lan, Steven J. Thomson, Yanbo Huang, W. Clint Hoffmann, Huihui Zhang

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

The first variable-rate aerial application system was developed about a decade ago in the USA and since then, aerial application has benefitted from these technologies. Many areas of the United States rely on readily available agricultural airplanes or helicopters for pest management, and variable-rate aerial application provides a solution for applying field inputs such as cotton growth regulators, defoliants, and insecticides. In the context of aerial application, variable-rate control can simply mean terminating spray over field areas that do not require inputs, terminating spray near pre-defined buffer areas determined by Global Positioning, or applying multiple rates to meet the variable …

Clustering Of Protein Families Into Functional Subtypes Using Relative Complexity Measure With Reduced Amino Acid Alphabets, Aydin Albayrak, Hasan H. Otu, Ugur O. Sezerman

Department of Electrical and Computer Engineering: Faculty Publications

Background: Phylogenetic analysis can be used to divide a protein family into subfamilies in the absence of experimental information. Most phylogenetic analysis methods utilize multiple alignment of sequences and are based on an evolutionary model. However, multiple alignment is not an automated procedure and requires human intervention to maintain alignment integrity and to produce phylogenies consistent with the functional splits in underlying sequences. To address this problem, we propose to use the alignment-free Relative Complexity Measure (RCM) combined with reduced amino acid alphabets to cluster protein families into functional subtypes purely on sequence criteria. Comparison with an alignment-based approach was …

Tob1 Is A Constitutively Expressed Repressor Of Liver Regeneration, Karen J. Ho, Nhue L. Do, Hasan H. Otu, Martin J. Dib, Xianghui Ren, Keiichi Enjyoji, Simon C. Robson, Ernest F. Terwilliger, Seth J. Karp

Department of Electrical and Computer Engineering: Faculty Publications

How proliferative and inhibitory signals integrate to control liver regeneration remains poorly understood. A screen for antiproliferative factors repressed after liver injury identified transducer of ErbB2.1 (Tob1), a member of the PC3/BTG1 family of mito-inhibitory molecules as a target for further evaluation. Tob1 protein decreases after 2/3 hepatectomy in mice secondary to posttranscriptional mechanisms. Deletion of Tob1 increases hepatocyte proliferation and accelerates restoration of liver mass after hepatectomy. Down-regulation of Tob1 is required for normal liver regeneration, and Tob1 controls hepatocyte proliferation in a dose-dependent fashion. Tob1 associates directly with both Caf1 and cyclindependent kinase (Cdk) 1 and …

Iterative Signal Processing In Communications, Christian Schlegel, Peter Hoeher, Owe Axelsson, Lance C. Pérez

Department of Electrical and Computer Engineering: Faculty Publications

Iterative signal processing in communications has experienced an explosive rise in popularity in recent years. The catalytic origins of this paradigm-shifting new philosophy among communications experts can be traced to the invention of turbo coding, and the subsequent rediscovery of low-density parity check (LDPC) coding, both in the field of error control coding. Both systems rely on iterative decoding algorithms to achieve their astounding performance. However, iterative signal processing is not confined to the decoding of error control codes and rather quickly spread to many other possible applications. The purpose of this special issue is to examine the concept of …

Mimo Self-Encoded Spread Spectrum With Iterative Detection Over Rayleigh Fading Channels, Shichuan Ma, Lim Nguyen, Won Mee Jang, Yaoqing (Lamar) Yang

Department of Electrical and Computer Engineering: Faculty Publications

Self-encoded spread spectrum (SESS) is a novel communication technique that derives its spreading code from the randomness of the source stream rather than using conventional pseudorandom noise (PN) code. In this paper, we propose to incorporate SESS in multiple-input multiple-output (MIMO) systems as a means to combat against fading effects in wireless channels. Orthogonal space-time block-coded MIMO technique is employed to achieve spatial diversity, and the inherent temporal diversity in SESS modulation is exploited with iterative detection. Simulation results demonstrate that MIMO-SESS can effectively mitigate the channel fading effect such that the system can achieve a bit error rate of …

About The Authors, Volume 28 (2010)

To Improve the Academy: A Journal of Educational Development

About the editors and authors of volume 28 (2010) of To Improve the Academy: A Journal of Educational Development.

Dysfunctional Illusions Of Rigor: Lessons From The Scholarship Of Teaching And Learning, Craig E. Nelson

To Improve the Academy: A Journal of Educational Development

My initial teaching practices were based on nine “dysfunctional illusions of rigor.” Overcoming them required revision of my ideas on the value of “hard” courses, the effectiveness of traditional methods, grade inflation, what students should be able to do initially, the fairness of traditional approaches, the importance of fixed deadlines, the importance of content coverage, the accessibility of critical thinking, and the appropriate bases for revising courses and curricula. I present the initial illusions and some more realistic views. These more realistic views are framed in terms of key research findings and some readily accessible models for improved practices.

The Case For Excellence In Diversity: Lessons From An Assessment Of An Early Career Faculty Program, Dorothe J. Bach, Mary Deane Sorcinelli

To Improve the Academy: A Journal of Educational Development

Many colleges and universities have come to understand the added educational value of having a more diverse faculty, and some have created specific programs to enhance recruitment, development, and retention of underrepresented faculty. How do these programs help underrepresented faculty start a successful career? How can they help a diverse faculty build thriving, long-term careers in academia? This chapter addresses these questions by sharing the findings and lessons learned from an internal and external assessment of the Excellence in Diversity Fellows Program at the University of Virginia.

A Soil Water Climatology For Kansas, Michael J. Keables, Shitij Mehta

Great Plains Research: A Journal of Natural and Social Sciences (through 2013)

Regional climate models suggest that summers in the Great Plains may become increasingly dry during this century, raising concern about the availability of water resources for irrigation and municipal water supplies. While the models predict drier conditions across the region, the impact of climate change on water availability at the local scale will depend largely upon the soils and their ability to store water during dry periods. This study presents a soil water climatology for Kansas using a climatic water balance approach. Monthly observations of temperature and precipitation for the period 1950–2006 are used to calculate climatologies of actual evapotranspiration, …

Three Decades In The Cold And Wet: A Career In Northern Archaeology, Sophia Perdikaris, George Hambrecht, Ramona Harrison

School of Global Integrative Studies: Faculty Publications

Thomas H. McGovern has been a pioneering researcher in the North Atlantic region for most of the past 40 years. He has taken his specialty in zooarchaeology beyond counting bones to actually addressing questions about human environment interactions and human response to extreme environmental events. A prolific writer and researcher with a multitude of publications and an impressive funding record, McGovern has always been a proponent of multidisciplinarity and international collaboration. His vision resulted in the creation of the North Atlantic Biocultural Organization (NABO) that currently has more than 400 scientific partners and has been leading projects throughout the Circum …

Feasibility Study Of Solar Driven Underground Cooling System, Michel E. Shafik

Durham School of Architectural Engineering and Construction: Dissertations, Theses, and Student Research

In the United States the peak electrical use occurs during the summer. In addition, the building sector consumes a major portion of the annual electrical energy consumption. One of the main energy consuming components in the building sector is the Heating, Ventilation, and Air-Conditioning (HVAC) systems. This research studies the feasibility of implementing a solar driven underground cooling system that could contribute to reducing building cooling loads. The developed system consists of an Earth-to-Air Heat Exchanger (EAHE) coupled with a solar chimney that provides a natural cool draft to the test facility building at the Solar Energy Research Test Facility …