Digital Commons Network^™

Effect Of Injury Mechanism And Severity On The Molecular Pathophysiology Of Traumatic Brain Injury, Brandon Mcdonald

Department of Agricultural and Biological Systems Engineering: Dissertations, Theses, and Student Research

Traumatic brain injury (TBI) mechanism and severity are heterogenous clinically, resulting in a multitude of physical, cognitive, and behavioral deficits. However, approximately 80% suffer from milder injuries. Thus, examining pathophysiological changes associated with mild TBI is imperative for improving clinical translation and evaluating the efficacy of potential therapeutic strategies. Through this work, we developed models of TBI, ranging in both injury mechanism and severity, using an electromagnetic controlled cortical impact (CCI) device. First, we characterized and optimized a closed head, mild TBI model (DTBI) to determine the clinical translatability and practicality of producing repeated mild injuries. Interestingly, we determined that …

Increased Signal-To-Noise Ratios Within Experimental Field Trials By Regressing Spatially Distributed Soil Properties As Principal Components, Jeffrey C. Berry, Mingsheng Qi, Balasaheb V. Sonawane, Amy Sheflin, Asaph Cousins, Jessica Prenni, Daniel P. Schachtman, Peng Liu, Rebecca S. Bart

Department of Agronomy and Horticulture: Faculty Publications

Environmental variability poses a major challenge to any field study. Researchers attempt to mitigate this challenge through replication. Thus, the ability to detect experimental signals is deter-mined by the degree of replication and the amount of environmental variation, noise, within the experimental system. A major source of noise in field studies comes from the natural heterogeneity of soil properties which create microtreatments throughout the field. In addition, the variation within different soil properties is often nonrandomly distributed across a field. We explore this challenge through a sorghum field trial dataset with accompanying plant, microbiome, and soil property data. Diverse sorghum …

Access To Online Formative Assessments In Introductory Biology Courses: Investigating Barriers To Student Engagement, Allison M. Upchurch

School of Biological Sciences: Dissertations, Theses, and Student Research

Instructors use a variety of online formative assessment (FA) activities to support learning outside of class. Previous studies have revealed barriers for students in online courses, but little is known about the barriers students experience when completing online FA assignments. Understanding these barriers to access is critical to fostering more inclusive learning for all students. Using a framework from previous work in online learning, we examined student perceptions of online FA access with respect to five barrier categories: technical resources, instructor organization, social interactions, personal engagement, and learning environment. We developed and administered a survey to over 1200 undergraduate biology …

Methanogen Metabolic Flexibility, Sean R. Carr

School of Biological Sciences: Dissertations, Theses, and Student Research

Methanogens are obligately anaerobic archaea which produce methane as a byproduct of their respiration. They are found across a wide diversity of environments and play an important role in cycling carbon in anaerobic spaces and the removal of harmful fermentation byproducts which would otherwise inhibit other organisms. Methanogens subsist on low-energy substrates which requires them to utilize a highly efficient central metabolism which greatly favors respiratory byproducts over biomass. This metabolic strategy creates high substrate:product conversion ratios which is industrially relevant for the production of biomethane, but may also allow for the production of value-added commodities. Particularly of interest are …

Sped 874: Language Arts And Literacy For Students Who Are Deaf/Hard Of Hearing, Anne E. Thomas

UNL Faculty Course Portfolios

This portfolio documents the process I used to critically analyze the structure, teaching methods, assessment, and students learning in SPED 874 Language Arts and Literacy for Children who are Dear/Hard of Hearing. This is a course that students in the Deaf Education Program at the University of Nebraska-Lincoln (UNL) take while pursuing a master’s degree and/or graduate endorsement in Deaf Education. This portfolio documents how I aligned the course objectives, content, and activities to the Council for Exceptional Children - Initial Specialty Set for Teachers of the Deaf/Hard of Hearing (CEC-DHH). I share the results of one method I use …

Data-Driven Prioritization And Empirical Predictions For Bridge Scour In Nebraska, Awgku Ahmad Hashim Awg Bolhasan

Department of Civil and Environmental Engineering: Dissertations, Theses, and Student Research

The effect of scour at the bridge substructure results in an increase in the vulnerability of the overall bridge stability. Previous studies have found that current guidelines are often overly-conservative with respect to scour. This project aims to provide guidance on hydraulic modeling parameters and reasonable scour estimates specific to Nebraska conditions. This will enable engineers to assess bridge sites for scour more precisely for efficient and effective design and countermeasures.

Four sites were surveyed for scour changes between the period of December 9, 2020, to April 20, 2021. At these four sites, overland and bathymetry survey data were collected. …

A General Equilibrium Assessment Of Covid-19’S Labor Productivity Impacts On China’S Regional Economies, Xi He, Edward J. Balistreri, Gyu Hyun Kim, Wendong Zhang

Department of Economics: Faculty Publications

This study introduces a database for analyzing COVID-19’s impacts on China’s regional economies. This database contains various sectoral and regional economic outcomes at the weekly and monthly level. In the context of a general equilibrium trade model, we first formulate a mathematical representation of the Chinese regional economy and calibrate the model with China’s multi-regional input-output table. We then utilize the monthly provincial and sectoral value-added and national trade series to estimate COVID-19’s province-by-month labor-productivity impacts from February 2020 to September 2020. As a year-on-year comparison, relative to February 2019 levels, we find an average 39.5% decrease in labor productivity …

Odontometric Sex Estimation Using A Modern Forensic Skeletal Collection, Andrea Sbei

Department of Anthropology: Theses and Student Research

Forensic anthropologists are responsible for estimating the biological profile—the age, sex, population affinity, and stature—of unknown deceased individuals. Many methods used for estimating the biological profile are sex-specific, which implicates sex estimation as one of the most important components of the biological profile. Historically, the skull and postcranial elements have been heavily utilized for morphological and metric sex estimation methods, whereas odontometric methods have been overlooked and underutilized. Odontometric data has proven to be a worthwhile avenue for the estimation of sex in several population-based studies (Acharya et al., 2011; Adams & Pilloud, 2019; Angadi et al., 2013; Cardoso, 2008; …

The Immorality Of Crimes Involving Moral Turpitude: Evaluating The Eighth Circuit’S Split In Bakor V. Barr, Emma Franklin

Nebraska Law Review

Alex failed to register his car, Pilar failed to renew his broker license, Juan failed to register as a sex offender, and all three noncitizens have been convicted of one previous crime. Each of these registration failures flow from dramatically different legal requirements and serve different purposes, but they share a common characteristic. All three legal missteps are based on administrative registration obligations promulgated by a governmental entity. Indeed, the failure to register as a sex offender may accompany more ethical and moral intimations, but the act of failing to register as a sex offender is not itself clearly evil …

Algorithmic Decision-Making And Corporate Risk: Toward Transparency Through Corporate Disclosures, Kevin X. Kuhn

Nebraska Law Review

Consider this hypothetical scenario: a national car seller implements an algorithmic decision-making system to raise profits by ten percent in the next year. The algorithm will target the most competitive geographic market for a particular vehicle, recommend a price, and screen consumers for creditworthiness. The algorithm is immensely successful, and the corporation achieves its goal for increased profits. But a disturbing trend emerges when multiple consumers file lawsuits alleging discriminatory practices. Consumers claim that the corporation gave Black borrowers with otherwise equal credentials less favorable loan terms than white borrowers. Barred from bringing suit by a contractual arbitration provision and …

In Celebration Of Morrissey V. Brewer At Fifty: A Surprising University Of Nebraska College Of Law Back Story To The Prisoners’ Rights Due Process Landmark, Russell E. Lovell Ii

Nebraska Law Review

The year 2022 will be the fiftieth anniversary of the Supreme Court’s 1972 landmark prisoners’ rights case, Morrissey v. Brewer.1 Morrissey was a Fourteenth Amendment due process challenge involving an Iowan whose parole was revoked without a hearing.2 But long before Mr. Morrissey was in prison, a legislative internship at the University of Nebraska College of Law (Nebraska Law) in 1968 got me involved in researching and drafting the Nebraska Treatment and Corrections Act of 1969, including state parole law. The one area of parole law not reformed by the new legislation was parole revocation, a shortcoming that was the …

Ultrafast Electron Diffraction: Visualizing Dynamic States Of Matter, D. Filipetto, P. Musumed, R. K. Li, B. J. Siwick, M. R. Otto, Martin Centurion, J. P.F. Nunes

Martin Centurion Publications

Since the discovery of electron-wave duality, electron scattering instrumentation has developed into a powerful array of techniques for revealing the atomic structure of matter. Beyond detecting local lattice variations in equilibrium structures with the highest possible spatial resolution, recent research efforts have been directed towards the long sought-after dream of visualizing the dynamic evolution of matter in real-time. The atomic behavior at ultrafast timescales carries critical information on phase transition and chemical reaction dynamics, the coupling of electronic and nuclear degrees of freedom in materials and molecules, the correlation between structure, function and previously hidden metastable or nonequilibrium states of …

Ultra-High Carrier Mobilities In Ferroelectric Domain Wall Corbino Cones At Room Temperature, Conor J. Mccluskey, Matthew G. Colbear, James P.V. Mcconville, Shane J. Mccartan, Jesi R. Maguire, Michele Conroy, Kalani Moore, Alan Harvey, Felix Trier, Ursel Bangert, Alexei Gruverman, Manuel Bibes, Amit Kumar, Raymong G.P. Mcquaid, J. Marty Gregg

Alexei Gruverman Publications

Recently, electrically conducting heterointerfaces between dissimilar band-insulators (such as lanthanum aluminate and strontium titanate) have attracted considerable research interest. Charge transport has been thoroughly explored and fundamental aspects of conduction firmly established. Perhaps surprisingly, similar insights into conceptually much simpler conducting homointerfaces, such as the domain walls that separate regions of different orientations of electrical polarisation within the same ferroelectric band-insulator, are not nearly so well-developed. Addressing this disparity, we herein report magnetoresistance in approximately conical 180° charged domain walls, which occur in partially switched ferroelectric thin film single crystal lithium niobate. This system is ideal for such measurements: firstly, …

Time-Varying Resonant Mass At Collider And Beam Dump Experiments, Jinhui Guo, Yuxuan He, Jia Liu, Xiao-Ping Wang, Ke-Pan Xie

Department of Physics and Astronomy: Faculty Publications

A new particle usually manifests itself as a single resonant peak located at its mass. We propose if the new particle mass is time-varying due to environmental effects, then its mass spectrum typically has a novel double-peak feature. A representative model is the kinetic mixing dark photon interacting with an ultralight complex scalar dark matter charged under U(1)'. We reanalyze the existing experiments, showing the constraints on such a model are drastically weakened than those on the traditional single-peak resonance model, due to the reduction of the luminosity exposure in each resonant mass bin. Consequently, for mass around tens …

First Search For Exclusive Diphoton Production At High Mass With Tagged Protons In Proton-Proton Collisions At √S =13 Tev, A. Tumasyan

Department of Physics and Astronomy: Faculty Publications

A search for exclusive two-photon production via photon exchange in proton-proton collisions, pp → pγγp with intact protons, is presented. The data correspond to an integrated luminosity of 9.4 fb⁻¹ collected in 2016 using the CMS and TOTEM detectors at a center-of-mass energy of 13 TeVat the LHC. Events are selected with a diphoton invariant mass above 350 GeVand with both protons intact in the final state, to reduce backgrounds from strong interactions. The events of interest are those where the invariant mass and rapidity calculated from the momentum losses of the forward-moving protons match the mass and rapidity …

The Dark Annulus Of A Drop In A Hele-Shaw Cell Is Caused By The Refraction Of Light Through Its Meniscus, Sangjin Ryu, Haipeng Zhang, Carson Emeigh

Department of Mechanical and Materials Engineering: Faculty Publications

Knowing the meniscus shape of confined drops is important for understanding how they make first contact and then coalesce. When imaged from the top view by brightfield microscopy, a liquid drop (e.g., corn syrup) confined in a Hele-Shaw cell, surrounded by immiscible liquid (e.g., mineral oil), had a dark annulus, and the width of the annulus decreased with increasing concentration of corn syrup. Since the difference in the annulus width was presumed to be related to the meniscus shape of the drops, three-dimensional images of the drops with different concentrations were obtained using confocal fluorescence microscopy, and their cross-sectional meniscus …

The Ddt-Induced Decline Influenced Genetic Diversity In Naturally Recovered Peregrine Falcons (Falco Peregrinus) Nesting Within The Alaska Arctic And Eastern Interior, Sarah A. Sonsthagen,, Ted Swem, Skip Ambrose, Melanie J. Flamme, Clayton M. White, George K. Sage, Sandra L. Talbot

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

We assessed the influence of the severe mid-20th century population decline on genetic diversity in nonaugmented Peregrine Falcon Falco peregrinus populations nesting within the Alaska Arctic and eastern Interior. Microsatellite and mitochondrial DNA (mtDNA) data were analysed for Peregrine Falcons sampled from three periods: pre-decline, decline and post-decline. The influence of the decline on genetic diversity differed between the two locales. The Alaska Arctic was characterized by shifts in mtDNA haplotype frequencies, increased inbreeding coefficient, reduction in effective population size and increase in private haplotypes, and a signature of post-decline population growth was detected; by contrast, the eastern Interior showed …

Induced Spin Textures At 3D Transition Metal–Topological Insulator Interfaces, Slimane Laref, Sumit Ghosh, Evgeny Y. Tsymbal, Aurelien Manchon

Department of Physics and Astronomy: Faculty Publications

While some of the most elegant applications of topological insulators, such as the quantum anomalous Hall effect, require the preservation of Dirac surface states in the presence of time-reversal symmetry breaking, other phenomena such as spin-charge conversion rather rely on the ability for these surface states to imprint their spin texture on adjacent magnetic layers. In this Rapid Communication, we investigate the spin-momentum locking of the surface states of a wide range of monolayer transition metals (3d-TM) deposited on top of Bi₂Se₃ topological insulators using first-principles calculations. We find an anticorrelation between the magnetic moment …

New Species, New Synonymies, A New Rank, And New Records In Desmiphorini, Saperdini, And Hemilophini (Coleoptera: Cerambycidae: Lamiinae), Antonio Santos-Silva, Robert A. Androw

Insecta Mundi

New information is presented for Neotropical Cerambycidae (Coleoptera). Dolichestola vittipennis Breuning, 1948 is synonymized with D. annulicornis Breuning, 1942, and the species is newly recorded from the Brazilian state of São Paulo. Dolichestola densepunctata Breuning, 1942 is newly recorded from Venezuela and Brazil, and the difference between it and D. annulicornis is reported. Mecas skillmani Santos-Silva and Androw, new species, is described from Mexico (Jalisco). Pannychella callicera (Bates, 1881) is illustrated, and notes on the genus and species are provided. Pannychis Thomson, 1864 is considered a genus different from Mecas LeConte, 1852, and notes on the genus …

Mentoring Undergraduate Research In Mathematical Modeling, Glenn Ledder

Department of Mathematics: Faculty Publications

In writing about undergraduate research in mathematical modeling, I draw on my 31 years as a mathematics professor at the University of Nebraska–Lincoln, where I mentored students in honors’ theses, REU groups, and research done in a classroom setting, as well as my prior experience. I share my views on the differences between research at the undergraduate and professional levels, offer advice for undergraduate mentoring, provide suggestions for a variety of ways that students can disseminate their research, offer some thoughts on mathematical modeling and how to explain it to undergraduates, and discuss the challenges involved in broadening research participation …

Mentoring Undergraduate Research In Mathematical Modeling, Glenn Ledder

Department of Mathematics: Faculty Publications

In writing about undergraduate research in mathematical modeling, I draw on my 31 years as a mathematics professor at the University of Nebraska–Lincoln, where I mentored students in honors’ theses, REU groups, and research done in a classroom setting, as well as my prior experience. I share my views on the differences between research at the undergraduate and professional levels, offer advice for undergraduate mentoring, provide suggestions for a variety of ways that students can disseminate their research, offer some thoughts on mathematical modeling and how to explain it to undergraduates, and discuss the challenges involved in broadening research participation …

Superfluid Spin Transistor, Edward Schwartz, Bo Li, Alexey Kovalev

Department of Physics and Astronomy: Faculty Publications

We propose to use the Hall response of topological defects, such as merons and antimerons, to spin currents in two-dimensional magnetic insulator with in-plane anisotropy for identification of the Berezinskii-Kosterlitz-Thouless (BKT) transition in a transistorlike geometry. Our numerical results relying on a combination of Monte Carlo and spin dynamics simulations show transition from spin superfluidity to conventional spin transport, accompanied by the universal jump of the spin stiffness and exponential growth of the transverse vorticity current. We propose a superfluid spin transistor in which the spin and vorticity currents are modulated by changes in density of free topological defects, e.g., …

Metaphylactic Antimicrobial Effects On Occurrences Of Antimicrobial Resistance In Salmonella Enterica, Escherichia Coli And Enterococcus Spp. Measured Longitudinally From Feedlot Arrival To Harvest In High-Risk Beef Cattle, Nathan S. Long, James E. Wells, Elaine D. Berry, Jerrad F. Legako, Dale R. Woerner, Guy H. Loneragan, Paul R. Broadway, Jeff A. Carroll, Nicole C. Burdick Sanchez, Samodha C. Fernando, Carley M. Bacon, Cory L. Helmuth, Taylor M. Smock, Jeff L. Manahan, Ashley A. Hoffman, Kristin E. Hales

Department of Animal Science: Faculty Publications

Aims: Our objective was to determine how injectable antimicrobials affected populations of Salmonella enterica, Escherichia coli and Enterococcus spp. in feedlot cattle.

Methods and Results: Two arrival date blocks of high-risk crossbred beef cattle (n = 249; mean BW = 244 kg) were randomly assigned one of four antimicrobial treatments administered on day 0: sterile saline control (CON), tulathromycin (TUL), ceftiofur (CEF) or florfenicol (FLR). Faecal samples were collected on days 0, 28, 56, 112, 182 and study end (day 252 for block 1 and day 242 for block 2). Hide swabs and subiliac …

Development Of Stresscheck: A Telehealth Motivational Enhancement Therapy To Improve Voluntary Engagement For Ptsd Treatment Among Active-Duty Service Members, Debra Kaysen, Thomas O. Walton, Issac C. Rhew, Anna E. Jaffe, Adam R. Pierce, Denise D. Walker

Department of Psychology: Faculty Publications

Background: Rates of PTSD in active-duty military are high relative to the general population. Although efficacious treatments exist, they are underutilized. Many service members with PTSD do not present for treatment and, of those who do, many do not receive sufficient doses of the interventions to receive full benefits. Motivational Enhancement Therapy (MET) “check-ups”, are brief interventions designed to elicit treatment engagement for those who are not treatment-seeking.

Methods: StressCheck is an MET for nontreatment seeking Army and Air Force personnel. StressCheck aims to improve PTSD and increase treatment engagement, especially around evidence-based interventions, as well as to …

Why Do Trump’S Authoritarian Followers Resist Covid-19 Authorities? Because They Are Not Really Authoritarian Followers, John Hibbing

Department of Political Science: Faculty Publications

People’s responses to the threat posed by COVID-19 varied widely. In direct contradiction to the popular theory that Trump supporters prefer to submit to powerful people, Trump’s most enthusiastic followers actually were the most vocal in resisting the urgings of authorities to get vaccinated and to wear masks. I explain this anomaly by showing that Trump’s followers are driven less by a desire for authority and more by a desire to be secure from the threats human outsiders pose to society’s historically dominant racial, language, religious, and cultural group. Far from being authoritarians, the followers of leaders such as Donald …

Population Genetics Reveals Bidirectional Fish Movement Across The Continental Divide Via An Interbasin Water Transfer, Audrey C. Harris, Sara J. Oyler-Mccance, Jennifer A. Fike, Matthew P. Fairchild, Christopher M. Kennedy, Harry J. Crockett, Dana L. Winkelman, Yoichiro Kanno

United States Geological Survey: Staff Publications

Interbasin water transfers are becoming an increasingly common tool to satisfy municipal and agricultural water demand, but their impacts on movement and gene flow of aquatic organisms are poorly understood. The Grand Ditch is an interbasin water transfer that diverts water from tributaries of the upper Colorado River on the west side of the Continental Divide to the upper Cache la Poudre River on the east side of the Continental Divide. We used single nucleotide polymorphisms to characterize population genetic structure in cutthroat trout (Oncorhynchus clarkii) and determine if fish utilize the Grand Ditch as a movement corridor. …

Characterizing The Interplay Of Rubisco And Nitrogenase Enzymes In Anaerobic-Photoheterotrophically Grown Rhodopseudomonas Palustris Cga009 Through A Genome-Scale Metabolic And Expression Model, Niaz Bahar Chowdhury, Adil Alsiyabi, Rajib Saha

Department of Chemical and Biomolecular Engineering: Faculty Publications

Rhodopseudomonas palustris CGA009 is a Gram-negative purple nonsulfur bacterium that grows phototrophically by fixing carbon dioxide and nitrogen or chemotrophically by fixing or catabolizing a wide array of substrates, including lignin breakdown products for its carbon and fixing nitrogen for its nitrogen requirements. It can grow aerobically or anaerobically and can use light, inorganic, and organic compounds for energy production. Due to its ability to convert different carbon sources into useful products during anaerobic growth, this study reconstructed a metabolic and expression (ME) model of R. palustris to investigate its anaerobic-photoheterotrophic growth. Unlike metabolic (M) models, ME models include transcription …

Gull Plumages Are, And Are Not, What They Appear To Human Vision, Muir D. Eaton, Pilar Benites, Luke Campillo, Robert E. Wilson, Sarah A. Sonsthagen

School of Natural Resources: Faculty Publications

Clear correlations between human and bird visual assessments of color have been documented, and are often assumed, despite fundamental differences in human and avian visual physiology and morphology. Analyses of plumage colors with avian perceptual models have shown widespread hidden inter-sexual and inter-specific color variation among passerines perceived as monochromatic to humans, highlighting the uncertainty of human vision to predict potentially relevant variation in color. Herein, we use reflectance data from 13 Larus gull species as an exemplar data set to study concordance between human vision and avian visual modeling of feather colors near, or below, the human threshold for …

The Status Of Posidonia Oceanica At Tremiti Islands Marine Protected Area (Adriatic Sea), Andrea Tursi, Francesco Mastrototaro, Federica Montesanto, Francesco De Giosa, Anna Lisco, Antonella Bottalico, Giovanni Chimienti

School of Natural Resources: Faculty Publications

Simple Summary: The seagrass Posidonia oceanica is the most important marine phanerogam of the Mediterranean Sea due to its meadows’ complexity, persistence, and extension. These habitats provide a suite of ecosystem goods and services, being of primary importance in marine conservation. Despite their central role in the coastal ecology, P. oceanica meadows are undergoing overall deterioration and fragmentation in the basin mostly due to anthropogenic impacts at local to global scales. In the last decades, several management measures have been proposed aiming to improve the meadow health conditions, while the periodic monitoring of P. oceanica meadows allows for verifying their …

A Room-Temperature Ferroelectric Resonant Tunneling Diode, Zhijun Ma,, Qi Zhang, Lingling Tao, Yihao Wang, Daniel Sando, Jinling Zhou, Yizhong Guo, Michael Lord, Peng Zhou, Yongqi Ruan, Zhiwei Wang, Alex Hamilton, Alexei Gruverman, Evgeny Y. Tsymbal, Tianjin Zhang, Nagarajan Valanoor

Department of Physics and Astronomy: Faculty Publications

Resonant tunneling is a quantum-mechanical effect in which electron transport is controlled by the discrete energy levels within a quantum-well (QW) structure. A ferroelectric resonant tunneling diode (RTD) exploits the switchable electric polarization state of the QW barrier to tune the device resistance. Here, the discovery of robust room-temperature ferroelectric-modulated resonant tunneling and negative differential resistance (NDR) behaviors in all-perovskite-oxide BaTiO₃/SrRuO₃/BaTiO₃ QW structures is reported. The resonant current amplitude and voltage are tunable by the switchable polarization of the BaTiO₃ ferroelectric with the NDR ratio modulated by ≈3 orders of magnitude and an OFF/ON …