Digital Commons Network^™

Coupling Dendrochronology And Remote Sensing Techniques To Assess The Biophysical Traits Of Juniperus Virginiana And Pinus Ponderosa Within Grassland Communities In The Semi-Arid Grasslands Of The Nebraska Sandhills, Reece Allen

School of Natural Resources: Dissertations, Theses, and Student Research

Woody species encroachment is occurring within the sandhills region in Nebraska, primarily driven by Juniperus virginiana and Pinus ponderosa, altering ecosystems and the services they provide. Effective, low cost, and cross-scale monitoring of woody species growth and performance is necessary for integrated grassland and forest management in the face of climate variability and change. In this study, we sought to establish a relationship between remote sensing-derived vegetation indices (VIs) and dendrochronological (raw and standardized tree ring width) measurements to assess the performance of encroaching woody J. virginiana and P. ponderosa located within the Nebraska National Forest in the sandhills. …

Stabilization By Adaptive Feedback Control For Positive Difference Equations With Applications In Pest Management, J. Edholm, C. Guiver, Richard Rebarber, Brigitte Tenhumberg, S. Townley

School of Biological Sciences: Faculty Publications

An adaptive feedback control scheme is proposed for stabilizing a class of forced nonlinear positive difference equations. The adaptive scheme is based on so-called high-gain adaptive controllers and contains substantial robustness with respect to model uncertainty as well as with respect to persistent forcing signals, including measurement errors. Our results take advantage of the underlying positive systems structure and ideas from input-to-state stability from nonlinear control theory. Our motivating application is to pest or weed control, and in this context the present work substantially strengthens previous work by the authors. The theory is illustrated with examples.

Comparing Airborne Algorithms For Greenhouse Gas Flux Measurements Over The Alberta Oil Sands, Broghan M. Erland, Cristen Adams, Andrea Darlington, Mackenzie L. Smith, Andrew K. Thorpe, Gregory R. Wentworth, Steve Conley, John Liggio, Shao-Meng Li, Charles E. Miller, John A. Gamon

School of Natural Resources: Faculty Publications

To combat global warming, Canada has committed to reducing greenhouse gases to be (GHGs) 40 %–45 % below 2005 emission levels by 2025. Monitoring emissions and deriving accurate inventories are essential to reaching these goals. Airborne methods can provide regional and area source measurements with small error if ideal conditions for sampling are met. In this study, two airborne mass-balance box-flight algorithms were compared to assess the extent of their agreement and their performance under various conditions. The Scientific Aviation’s (SciAv) Gaussian algorithm and the Environment and Climate Change Canada’s top-down emission rate retrieval algorithm (TERRA) were applied to data …

Spin-Neutral Tunneling Anomalous Hall Effect, Ding-Fu Shao, Shu-Hui Zhang, Rui-Chun Xiao, Zi-An Wang, W. J. Lu, Y. P. Sun, Evgeny Y. Tsymbal

Department of Physics and Astronomy: Faculty Publications

Anomalous Hall effect (AHE) is a fundamental spin-dependent transport property that is widely used in spintronics. It is generally expected that currents carrying net spin polarization are required to drive the AHE. Here we demonstrate that, in contrast to this common expectation, a spin-neutral tunneling AHE (TAHE), i.e. a TAHE driven by spin-neutral currents, can be realized in an antiferromagnetic (AFM) tunnel junction where an AFM electrode with a non-spin-degenerate Fermi surface and a normal metal electrode are separated by a non-magnetic barrier with strong spin-orbit coupling (SOC). The symmetry mismatch between the AFM electrode and the SOC barrier results …

Spatial Stream Modeling Of Louisiana Waterthrush (Parkesia Motacilla) Foraging Substrate And Aquatic Prey In A Watershed Undergoing Shale Gas Development, Mack W. Frantz, Petra B. Wood, Steven C. Latta

United States Geological Survey: Staff Publications

We demonstrate the use of spatial stream network models (SSNMs) to explore relationships between a semiaquatic bioindicator songbird, Louisiana Waterthrush (Parkesia motacilla), and stream monitoring and benthic macroinvertebrate data in an area undergoing shale gas development. SSNMs allowed us to account for spatial autocorrelation inherent to these environmental data types and stream properties that traditional modeling approaches cannot capture to elucidate factors that affect waterthrush foraging locations. We monitored waterthrush along 58.1 km of 1st- and 2nd-order headwater stream tributaries (n = 14) in northwestern West Virginia over a two year period (2013–2014), sampled benthic macroinvertebrates in waterthrush …

Optimising Response To An Introduction Of African Swine Fever In Wild Pigs, Kim M. Pepin, Vienna R. Brown, Anni Yang, James C. Beasley, Raoul Boughton, Kurt C. Vercauteren, Ryan S. Miller, Sarah N. Bevins

United States Department of Agriculture Wildlife Services: Staff Publications

African swine fever virus (ASFv) is a virulent pathogen that threatens domestic swine industries globally and persists in wild boar populations in some countries. Persistence in wild boar can challenge elimination and prevent disease-free status, making it necessary to address wild swine in proactive response plans. In the United States, invasive wild pigs are abundant and found across a wide range of ecological conditions that could drive different epidemiological dynamics among populations. Information on the size of the control areas required to rapidly eliminate the ASFv in wild pigs and how this area should change with management constraints and local …

Nmr And Metabolomics—A Roadmap For The Future, David S. Wishart, Leo L. Cheng, Valérie Copié, Arthur S. Edison, Hamid R. Eghbalnia, Jeffrey C. Hoch, Goncalo J. Gouveia, Wimal Pathmasiri, Robert Powers, Tracey B. Schock, Lloyd W. Sumner, Mario Uchimiya

Department of Chemistry: Faculty Publications

Metabolomics investigates global metabolic alterations associated with chemical, biological, physiological, or pathological processes. These metabolic changes are measured with various analytical platforms including liquid chromatography-mass spectrometry (LC-MS), gas chromatographymass spectrometry (GC-MS) and nuclear magnetic resonance spectroscopy (NMR). While LC-MS methods are becoming increasingly popular in the field of metabolomics (accounting for more than 70% of published metabolomics studies to date), there are considerable benefits and advantages to NMR-based methods for metabolomic studies. In fact, according to PubMed, more than 926 papers on NMR-based metabolomics were published in 2021—the most ever published in a given year. This suggests that NMR-based metabolomics …

Profiling A Community-Specific Function Landscape For Bacterial Peptides Through Protein-Level Meta-Assembly And Machine Learning, Mitra Vajjala, Brady Johnson, Lauren Kasparek, Michael Leuze, Qiuming Yao

School of Computing: Faculty Publications

Small proteins, encoded by small open reading frames, are only beginning to emerge with the current advancement of omics technology and bioinformatics. There is increasing evidence that small proteins play roles in diverse critical biological functions, such as adjusting cellular metabolism, regulating other protein activities, controlling cell cycles, and affecting disease physiology. In prokaryotes such as bacteria, the small proteins are largely unexplored for their sequence space and functional groups. For most bacterial species from a natural community, the sample cannot be easily isolated or cultured, and the bacterial peptides must be better characterized in a metagenomic manner. The bacterial …

Spatio-Temporal Models Of Infectious Disease With High Rates Of Asymptomatic Transmission, Aminur Rahman, Angela Peace, Ramesh Kesawan, Souparno Ghosh

Department of Statistics: Faculty Publications

The surprisingly mercurial Covid-19 pandemic has highlighted the need to not only accelerate research on infectious disease, but to also study them using novel techniques and perspectives. A major contributor to the dificulty of containing the current pandemic is due to the highly asymptomatic nature of the disease. In this investigation, we develop a modeling framework to study the spatio-temporal evolution of diseases with high rates of asymptomatic transmission, and we apply this framework to a hypothetical country with mathematically tractable geography; namely, square counties uniformly organized into a rectangle. We first derive a model for the temporal dynamics of …

Application Of Digital Twin In Evaluating Quality Changes In Tomato Value-Chain In Nigeria, Charles Nwaizu, Taofiq Olayinka Olanrewaju, Iluno Christiana

Department of Food Science and Technology: Faculty Publications

Cooling tomatoes after harvesting and keeping them refrigerated during their transportation is a key step toward preserving the quality attributes of tomatoes. This is a challenging task to accomplish in Nigeria, mainly because shipments of tomatoes from the tomato-producing states in northern Nigeria to the non-producing states in southern Nigeria were predominately not transported in a refrigerated ambient condition. To minimize postharvest losses of tomatoes during transportation, quantification of changes in quality would be extremely valuable. For this purpose, a digital tomato twin was developed based on mechanistic physics-based modeling. This digital twin simulated the actual thermal profile of tomatoes …

Domains Of Vulnerability, Resilience, Health Habits, And Mental And Physical Health For Health Disparities Research, Rebecca M. Wolfe, Katie Beck-Felts, Brianna Speakar, William D. Spaulding

Department of Psychology: Faculty Publications

Health disparities associated with severe mental illness (SMI) have become a major public health concern. The disparities are not directly due to the SMI. They involve the same leading causes of premature death as in the general population. The causes of the disparities are therefore suspected to reflect differences in health-related behavior and resilience. As with other problems associated with SMI, studying non-clinical populations at risk for future onset provides important clues about pathways, from vulnerability to unhealthy behavior and compromised resilience, to poor health and reduced quality of life. The purpose of this study was to identify possible pathways …

Internal Model Control (Imc)-Based Active And Reactive Power Control Of Brushless Double-Fed Induction Generator With Notch Filter, Ahsanullah Memon, Mohd Wazir Bin Mustafa, Zohaib Hussain Laghari, Touqeer Ahmed Jumani, Waqas Anjum, Shafi Ullah, Muhammad Naveed Aman

School of Computing: Faculty Publications

The increase in demand for electricity and, in particular, green energy has put renewable energy systems at the focal point of energy policy worldwide. The higher reliability of brushless doubly fed induction generators (BDFIGs) makes them suitable for offshore and remote wind energy generation (WEG) applications. Besides, controlling the active and reactive powers in an electrical power system is critical for optimal voltage regulation, reduced power losses, and enhanced utilization of installed equipment. However, the existing literature on BDFIG’s active and reactive power control highlights the poor dynamic response and high transients with harmonic generation during inductive load insertion. It …

Combining Solution Reuse And Bound Tightening For Efficient Analysis Of Evolving Systems, Clay Stevens, Hamid Bagheri

School of Computing: Conference and Workshop Papers

Software engineers have long employed formal verification to ensure the safety and validity of their system designs. As the system changes—often via predictable, domain-specific operations—their models must also change, requiring system designers to repeatedly execute the same formal verification on similar system models. State-of-the-art formal verification techniques can be expensive at scale, the cost of which is multiplied by repeated analysis. This paper presents a novel analysis technique—implemented in a tool called SoRBoT—which can automatically determine domain-specific optimizations that can dramatically reduce the cost of repeatedly analyzing evolving systems. Different from all prior approaches, which focus on either tightening the …

Amplification Of Black Vulture (Coragyps Atratus) Dna From Regurgitated Food Pellets, Daniel R. Taylor, Bryan M. Kluever, John S. Humphrey, Iona M. Hennessy, Amber Sutton, William E. Bruce, Antoinette J. Piaggio

United States Department of Agriculture Wildlife Services: Staff Publications

Studies that rely on noninvasive collection of DNA for birds often use feces or feathers. Some birds, such as vultures, regurgitate undigested matter in the form of pellets that are commonly found under roost sites. Our research demonstrates that regurgitated pellets are a viable, noninvasive source of DNA for molecular ecology studies of vultures. Our objectives were to amplify 5 microsatellite loci designed for distinguishing Turkey Vultures (Cathartes aura) and Black Vultures (Coragyps atratus) in a single, multiplexed PCR, and to determine how long the target nuclear DNA persists after a vulture pellet is regurgitated and …

Reading Contemporary French Literature, Warren Motte

Zea E-Books Collection

This book focuses upon a dozen French writers who have helped to set the terms for contemporary French literature and its horizon of possibility. Though they have pursued significantly different paths, each one of them is committed to the principle of literary innovation, to making French literature new. They work in full cognizance of literary history and of the tradition that they inherit, even as they reshape that tradition in each of their books. They invite their readers to take a critical stance with regard to those books, and to participate actively in the construction of literary meaning. Both bold …

Negative Photoresponse In Ti3C2TX Mxene Monolayers, Nataliia S. Vorobeva, Saman Bagheri, Angel Torres, Alexander Sinitskii

Department of Chemistry: Faculty Publications

Two-dimensional transition metal carbides, nitrides, and carbonitrides, collectively known as MXenes, are finding numerous applications in many different areas, including optoelectronics and photonics, but there is limited information about their intrinsic photoresponse. In this study, we investigated the visible and near-infrared range photoresponse of Ti₃C₂T_x, the most popular MXene material to date. The electrical measurements were performed on devices based on individual monolayer Ti₃C₂T_x MXene flakes, which were characterized by a variety of microscopic and spectroscopic methods. For MXene devices with different electrode layouts, the current reproducibly decreased under …

Characterization Of Three-Dimensional Fractional Viscoelastic Models Through Complex Modulus Analysis And Polar Decomposition, Avradip Ghosh, Avinash Kumar Both, Chin Li Cheung

Department of Chemistry: Faculty Publications

Soft materials such as gels, elastomers, and biological tissues have diverse applications in nature and technology due to their viscoelastic nature. These soft materials often exhibit complex rheology and display elastic and viscous characteristics when undergoing deformation. In recent years, fractional calculus has emerged as a promising tool to explain the viscoelastic behavior of soft materials. Scalar constants are primarily used to quantify viscoelastic elements such as springs and dashpots. However, in three-dimensional (3D) space, not all materials show the same elastic or viscoelastic properties in all directions, especially under elastic/viscoelastic wave propagation (or anisotropy). Though previously reported studies on …

Search For Flavor-Changing Neutral Current Interactions Of The Top Quark And Higgs Boson In Final States With Two Photons In Proton-Proton Collisions At √S =13 Tev, A. Tumasyan

Department of Physics and Astronomy: Faculty Publications

Proton-proton interactions resulting in final states with two photons are studied in a search for the signature of flavor-changing neutral current interactions of top quarks (t) and Higgs bosons (H). The analysis is based on data collected at a center-of-mass energy of 13 TeV with the CMS detector at the LHC, corresponding to an integrated luminosity of 137 fb⁻¹. No significant excess above the background prediction is observed. Upper limits on the branching fractions (Ɓ) of the top quark decaying to a Higgs boson and an up (u) or charm …

Science Of The Total Environment, Benjamin Linhoff

United States Geological Survey: Staff Publications

Recently, the subsoils of ephemeral stream(arroyos) floodplains in the northern Chihuahuan Desert were discovered to contain large naturally occurring NO₃⁻ reservoirs (floodplain:~38,000 kg NO₃-N/ha; background:~60 kg NO₃-N/ha). These reservoirs may be mobilized through land use change or natural stream channel migration which makes differentiating between anthropogenic and natural groundwaterNO₃⁻sources challenging. In this study, the fate and sources of NO₃⁻ were investigated in an area with multiple NO₃⁻ sources such as accidental sewer line releases and sewage lagoons aswell as natural reservoirs of subsoil NO₃⁻. …

Multiplexed Monitoring Of Neurochemicals Via Electrografting- Enabled Site-Selective Functionalization Of Aptamers On Field-Effect Transistors, Zan Gao, Guangfu Wu, Yang Song, Huijie Li, Yuxuan Zhang, Michael J. Schneider, Yingqi Qiang, Jackson Kaszas, Zhengyan Weng, He Sun, Bryan D. Huey, Rebecca Lai, Yi Zhang

Department of Chemistry: Faculty Publications

Neurochemical corelease has received much attention in understanding brain activity and cognition. Despite many attempts, the multiplexed monitoring of coreleased neurochemicals with spatiotemporal precision and minimal crosstalk using existing methods remains challenging. Here, we report a soft neural probe for multiplexed neurochemical monitoring via the electrografting-assisted site-selective functionalization of aptamers on graphene field-effect transistors (G-FETs). The neural probes possess excellent flexibility, ultralight mass (28 mg), and a nearly cellular-scale dimension of 50 μm × 50 μm for each G-FET. As a demonstration, we show that G-FETs with electrochemically grafted molecular linkers (−COOH or −NH2) and specific aptamers can be used …

Explosive Spontaneous Emulsification, Xuefei Wu, Gautam Bordia, Robert Streubel, Jaffar Hasnain, Ahmad K. Omar, Phillip L. Geissler, Dong Wang, Han Xue, Jianjun Wang, Thomas P. Russell

Department of Physics and Astronomy: Faculty Publications

Spontaneous emulsification, resulting from the assembly and accumulation of surfactants at liquid-liquid interfaces, is an interfacial instability where microdroplets are generated and diffusively spread from the interface until complete emulsification. Here, we show that an external magnetic field can modulate the assembly of paramagnetic nanoparticle surfactants (NPSs) at liquid-liquid interfaces and trigger an oversaturation in the areal density of the NPSs at the interface, as evidenced by the reduction in the interfacial tension, γ, and corroborated with a magnetostatic continuum theory. Despite the significant reduction in γ, the presence of the magnetic field does not cause stable interfaces to become …

Seasonal Climatic Niche And Migration Movements Of Double-Crested Cormorants, D. Tommy King, Guiming Wang, Fred L. Cunningham

United States Department of Agriculture Wildlife Services: Staff Publications

Avian migrants are challenged by seasonal adverse climatic conditions and energetic costs of long-distance flying. Migratory birds may track or switch seasonal climatic niche between the breeding and non-breeding grounds. Satellite tracking enables avian ecologists to investigate seasonal climatic niche and circannual movement patterns of migratory birds. The Double-crested Cormorant (Nannopterum auritum, hereafter cormorant) wintering in the Gulf of Mexico (GOM) migrates to the Northern Great Plains and Great Lakes and is of economic importance because of its impacts on aquaculture. We tested the climatic niche switching hypothesis that cormorants would switch climatic niche between summer and winter …

Nabat Ml: Utilizing Deep Learning To Enable Crowdsourced Development Of Automated, Scalable Solutions For Documenting North American Bat Populations, Ali Khalighifar, Benjamin S. Gotthold, Erin Adams, Jenny Barnett, Laura O. Beard, Eric R. Britzke, Paul A. Burger, Kimberly Chase, Zackary Cordes, Paul M. Cryan, Emily Emily, Christopher T. Fill, Scott E. Gibson, G. Scott Haulton, Kathryn M. Irvine, Lara S. Katz, William L. Kendall, Christen A. Long, Oisin Mac Aodha, Tessa Mcburney, Sara Mccarthy, Matthew W. Mckown, Joy O'Keefe, Lucy D. Patterson, Kristopher A. Pitcher, Matthew Rustand, Jordi L. Segers, Kyle Seppanen, Jeremy L. Siemers, Christian Stratton, Bethany R. Straw, Theodore J. Weller, Brian E. Reichert

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

1. Bats play crucial ecological roles and provide valuable ecosystem services, yet many populations face serious threats from various ecological disturbances. The North American Bat Monitoring Program (NABat) aims to use its technology infrastructure to assess status and trends of bat populations, while developing innovative and community-driven conservation solutions.

2. Here, we present NABat ML, an automated machine-learning algorithm that improves the scalability and scientific transparency of NABat acoustic monitoring. This model combines signal processing techniques and convolutional neural networks (CNNs) to detect and classify recorded bat echolocation calls. We developed our CNN model with internet-based computing resources (‘cloud environment’), and …

   ---

   Go to article

Phase Space Analysis Of Nonlinear Wave Propagation In A Bistable Mechanical Metamaterial With A Defect, Mohammed A. Mohammed, Piyush Grover

Department of Mechanical and Materials Engineering: Faculty Publications

We study the dynamics of solitary waves traveling in a one-dimensional chain of bistable elements in the presence of a local inhomogeneity (`defect'). Numerical simulations reveal that depending upon its initial speed, an incoming solitary wave can get transmitted, captured or reflected upon interaction with the defect. The dynamics are dominated by energy exchange between the wave and a breather mode localized at the defect. We derive a reduced-order two degree of freedom Hamiltonian model for wave-breather interaction, and analyze it using dynamical systems techniques. Lobe dynamics analysis reveals the fine structure of phase space that leads to the complicated …

Consemblex: A Consensus-Based Transcriptome Assembly Approach That Extends Consemble And Improves Transcriptome Assembly, Richard Mwaba

School of Computing: Dissertations, Theses, and Student Research

An accurate transcriptome is essential to understanding biological systems enabling omics analyses such as gene expression, gene discovery, and gene-regulatory network construction. However, assembling an accurate transcriptome is challenging, especially for organisms without adequate reference genomes or transcriptomes. While several methods for transcriptome assembly with different approaches exist, it is still difficult to establish the most accurate methods. This thesis explores the different transcriptome assembly methods and compares their performances using simulated benchmark transcriptomes with varying complexity. We also introduce ConSemblEX to improve a consensus-based ensemble transcriptome assembler, ConSemble, in three main areas: we provide the ability to use any …

Probing Charm Quark Dynamics Via Multiparticle Correlations In Pb-Pb Collisions At √SNn =5.02 Tev, A. Tumasyan

Department of Physics and Astronomy: Faculty Publications

Multiparticle azimuthal correlations of prompt D⁰ mesons are measured in Pb-Pb collisions at a nucleon-nucleon center-of-mass energy of √^sNN = 5.02 TeV. For the first time, a four-particle cumulant method is used to extract the second Fourier coefficient of the azimuthal distribution (ν₂) of D⁰ mesons as a function of event centrality and the D⁰ transverse momentum. The ratios of the four-particle v₂ values to previously measured two-particle cumulant results provide direct experimental access to event-by-event fluctuations of charm quark azimuthal anisotropies. These ratios are also found to be comparable to …

Many Cliques In Bounded-Degree Hypergraphs, Rachel Kirsch, J. Radcliffe

Department of Mathematics: Faculty Publications

Recently Chase determined the maximum possible number of cliques of size t in a graph on n vertices with given maximum degree. Soon afterward, Chakraborti and Chen answered the version of this question in which we ask that the graph have m edges and fixed maximum degree (without imposing any constraint on the number of vertices). In this paper we address these problems on hypergraphs. For s-graphs with s ≥ 3 a number of issues arise that do not appear in the graph case. For instance, for general s-graphs we can assign degrees to any i-subset of the vertex set …

Reply To Response By Fbi Laboratory Filed In Illinois V. Winfield And Affidavit By Biederman Et Al. (2022) Filed In Us V. Kaevon Sutton (2018 Cf1 009709), Susan Vanderplas, Kori Khan, Heike Hofmann, Alicia Carriquiry

Department of Statistics: Faculty Publications

1 Preliminaries

1.1 Scope

The aim of this document is to respond to issues raised in Federal Bureau of Investigation¹ and Alex Biedermann, Bruce Budowle & Christophe Champod.²

1.2 Conflict of Interest

We are statisticians employed at public institutions of higher education (Iowa State University and University of Nebraska, Lincoln) and have not been paid for our time or expertise when preparing either this response or the original affidavit.³ We provide this information as a public service and as scientists and researchers in this area.

1.3 Organization

The rest of the document precedes as follows: we begin …

Droughtscape, Summer 2022, National Drought Mitigation Center

DroughtScape: Quarterly Newsletter of the National Drought Mitigation Center (2007–2023)

DroughtScape, Summer 2022

Asymmetric Control Of Light At The Nanoscale, Christos Argyropoulos

Department of Electrical and Computer Engineering: Faculty Publications

Breaking reciprocity at the nanoscale can produce directional formation of images due to the asymmetric nonlinear optical response of subwavelength anisotropic resonators. The self-induced passive non-reciprocity has advantages compared to magnet or time modulation approaches and may impact both classical and quantum photonics.