Physical Sciences and Mathematics Commons^™

Pollinator Communities And Their Ecosystem Services At Conservation Grasslands And Adjacent Croplands, Araceli Gomez Villegas

Department of Entomology: Dissertations, Theses, and Student Research

Pollinators are intrinsically linked to the success of unmanaged and managed ecosystems by providing pollination services that aid in the reproduction of wildflowers and many crops. Land use change, habitat loss, fragmentation, and related landscape-level phenomena (for example, increased pesticide exposure) threaten pollinators and have been associated with population declines. In the Midwestern region of the United States, land conversion of native prairies and grasslands to row-crop agriculture has been one of the largest contributors to pollinator habitat loss. Conservation programs, such as the Conservation Reserve Program, have worked towards removing environmentally sensitive lands from agriculture production and enrolling them …

Weakly Supervised Attention-Based Recognition Under Spectral, Turbulence, And Resource Variations, Kshitij Naresh Nikhal

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

While supervised optimization paradigms are ubiquitous across diverse recognition systems, the risk of over-fitting and increasing bias have limited their applicability.

This dissertation focuses on unsupervised learning—learning without precisely curated data—and argues that unsupervised learning methods can enable both discriminability and generalizability. Through the use of attention-based machine learning and advanced clustering, unsupervised methods are able to focus on fine-grained information in images without any explicit supervision. The dissertation introduces a domain-bridging framework for tasks like cross-spectrum matching and long-range recognition, utilizing intra-domain clustering and inter-domain matching to generate pseudo-labels. Additionally, a hash-based network is proposed to accelerate the search …

Quantum Computing And U.S. Cybersecurity: A Case Study Of The Breaking Of Rsa And Plan For Cryptographic Algorithm Transition, Helena Holland

Honors Program: Senior Projects (Public)

The invention of a cryptographically relevant quantum computer would revolutionize computing power, transforming industry and national security. While a theoretical possibility at the time of this writing, the ability of quantum algorithms to solve the factoring and discrete logarithm problems, upon which all currently employed public-key cryptography depends, presents a serious threat to digital communications. This research examines both the mathematics and government policy behind these risks and their implications for cybersecurity. Specifically, a case study of RSA, Shor’s algorithm, and the American Intelligence Community’s plan to transition toward quantum-resistant algorithms is presented to analyze quantum threats and opportunities and …

Soil Nitrate Prediction Using Ftir-Atr, Vis-Nir, And Raman Spectroscopy, Sabiha Ferdous

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

Fourier transform infrared spectroscopy (FTIR) combined with Attenuated total reflectance (ATR), Visible-Near Infrared spectroscopy (Vis-NIR), and Raman spectroscopy (RS) are non-destructive techniques for rapid determination of nitrogen compounds in soil. Leveraging FTIR-ATR and Vis-NIR spectra using partial least squares regression (PLSR) modeling, the study aims to predict soil nitrate content and explored the feasibility of Raman spectroscopy to detect nitrate (NO₃^-), nitrite (NO₂^-), and ammonium (NH₄⁺) in soil. Soil samples were collected from four different fields, dried, sieved (2mm), and then used for collecting spectra (FTIR-ATR and Vis-NIR). Laboratory analysis was …

Cancer-Associated Fibroblast-Derived Acetate Promotes Pancreatic Cancer Development By Altering Polyamine Metabolism Via The Acss2–Sp1–Sat1 Axis, Divya Murthy, Kuldeep S. Attri, Surendra K. Shukla, Ravi Thakur, Nina V. Chaika, Chunbo He, Dezhen Wang, Kanupriya Jha, Aneesha Dasgupta, Ryan J. King, Scott E. Mulder, Joshua Souchek, Teklab Gebregiworgis, Vikant Rai, Rohit Patel, Tuo Hu, Sandeep Rana, Sai Sundeep Kollala, Camila Pacheco, Paul M. Grandgenett, Fang Yu, Vikas Kumar, Audrey J. Lazenby, Adrian R. Black, Susanna Ulhannan, Ajay Jain, Barish H. Edil, David L. Klinkebiel, Robert Powers, Amarnath Natarajan, Michael A. Hollingsworth, Kamiya Mehla2,, Quan Ly, Sarika Chaudhary, Rosa F. Hwang, Kathryn E. Wellen, Pankaj K. Singh

Robert Powers Publications

The ability of tumour cells to thrive in harsh microenvironments depends on the utilization of nutrients available in the milieu. Here we show that pancreatic cancer-associated fibroblasts (CAFs) regulate tumour cell metabolism through the secretion of acetate, which can be blocked by silencing ATP citrate lyase (ACLY) in CAFs. We further show that acetyl-CoA synthetase short-chain family member 2 (ACSS2) channels the exogenous acetate to regulate the dynamic cancer epigenome and transcriptome, thereby facilitating cancer cell survival in an acidic microenvironment. Comparative H3K27ac ChIP–seq and RNA–seq analyses revealed alterations in polyamine homeostasis through regulation of SAT1 gene expression and enrichment …

Securing Synchrophasors Using Data Provenance In The Quantum Era, Kashif Javed, Mansoor Ali Khan, Mukhtar Ullah, Muhammad Naveed Aman, Biplab Sikdar

School of Computing: Faculty Publications

Trust in the fidelity of synchrophasor measurements is crucial for the correct operation of modern power grids. While most of the existing research on data provenance focuses on the Internet of Things, there is a significant need for effective malicious data detection in power systems. Current methods either fail to detect malicious data modifications or require certain Phasor Measurement Units (PMUs) to be physically secured. To solve these issues, this paper presents a new protocol to establish data provenance in synchrophasor networks. The proposed protocol is based on Physically Unclonable Functions (PUFs) and harnesses the principles of quantum unreality and …

Editorial: Ipps 2022 - Plant Phenotyping For A Sustainable Future, Elias Kaiser, Philipp Von Gillhaussen, Jennifer Clarke, Ulrich Schurr

Department of Statistics: Faculty Publications

Plants are a venue for addressing the challenges facing humanity. The need for a reliable supply of food, feed, materials, chemicals and energy as well as ways to manage agroecology and climate change are among the challenges that we can address through the sustainable use of plants and plant ecosystems. The research community needs to integrate plant systems approaches, from molecular to organismal to applications in the field and ecosystems, to increase productivity sustainably while using fewer land, water, and nutrient resources. In the past two decades, plant phenotyping research has developed a highly valuable portfolio of technologies, processes and …

Tunable Magnetic Coupling In Graphene Nanoribbon Quantum Dots, Peter H. Jacobse, Mamun Sarker, Anshul Saxena, Brookhaven National Laboratory, Ziyi Wang, Emma Berger, Narayana R. Aluru, Alexander Sinitskii, Michael F. Crommie

Department of Chemistry: Faculty Publications

Carbon-based quantum dots (QDs) enable flexible manipulation of electronic behavior at the nanoscale, but controlling their magnetic properties requires atomically precise structural control. While magnetism is observed in organic molecules and graphene nanoribbons (GNRs), GNR precursors enabling bottom-up fabrication of QDs with various spin ground states have not yet been reported. Here the development of a new GNR precursor that results in magnetic QD structures embedded in semiconducting GNRs is reported. Inserting one such molecule into the GNR backbone and graphitizing it results in a QD region hosting one unpaired electron. QDs composed of two precursor molecules exhibit nonmagnetic, antiferromagnetic, …

What Waterfowl Hunters Want: Exploring Heterogeneity In Hunting Trip Preferences, Katherine A. Sainsbury, Howard W. Harshaw, David C. Fulton, Nicholas W. Cole, Ashley A. Dayer, Jennie N. Duberstein, Andrew H. Raedeke, Rudy M. Schuster, Mark P. Vrtiska

School of Natural Resources: Faculty Publications

Canadian and American waterfowl hunters were surveyed to identify their hunting trip preferences. Respondents were individuals that were now participating or had participated in waterfowl hunting, and most had hunted the majority of the last five years. We identified four latent classes of waterfowl hunters that varied in their preferences for harvest, access effort, length of travel, quantity of waterfowl seen, and the potential for interference/competition. We found a diminishing return associated with the number of waterfowl harvested, and that ‘devoted’ and ‘local’ hunters did not perceive appreciable benefit from harvesting more birds beyond harvesting a single bird. Results highlight …

Intermittent-Aware Design Exploration Of Systolic Array Using Various Non-Volatile Memory: A Comparative Study, Nedasadat Taheri, Sepehr Tabrizchi, Arman Roohi

School of Computing: Faculty Publications

This paper conducts a comprehensive study on intermittent computing within IoT environments, emphasizing the interplay between different dataflows—row, weight, and output—and a variety of non-volatile memory technologies. We then delve into the architectural optimization of these systems using a spatial architecture, namely IDEA, with their processing elements efficiently arranged in a rhythmic pattern, providing enhanced performance in the presence of power failures. This exploration aims to highlight the diverse advantages and potential applications of each combination, offering a comparative perspective. In our findings, using IDEA for the row stationary dataflow with AlexNet on the CIFAR10 dataset, we observe a power …

Heavy Metal Movement Through Insect Food Chains In Pristine Thermal Springs Of Yellowstone National Park, Braymond Adams, John Bowley, Monica Rohwer, Erik Oberg, Kelly Willemssens, Wendy Wintersteen, Robert K.D. Peterson, Leon G. Higley

School of Natural Resources: Faculty Publications

Yellowstone National Park thermal features regularly discharge various heavy metals and metalloids. These metals are taken up by microorganisms that often form mats in thermal springs. These microbial mats also serve as food sources for invertebrate assemblages. To examine how heavy metals move through insect food webs associated with hot springs, two sites were selected for this study. Dragon-Beowulf Hot Springs, acid-sulfate chloride springs, have a pH of 2.9, water temperatures above 70 ^oC, and populations of thermophilic bacterial, archaeal, and algal mats. Rabbit Creek Hot Springs, alkaline springs, have a pH of up to 9, some water temperatures …

Analysis Of Legacy Gravity Data Reveals Sediment-Filled Troughs Buried Under Flathead Valley, Montana, Usa, Ali Gebril, Mohamed A. Khalil, Robert Matthew Joeckel, James Rose

Conservation and Survey Division: Faculty and Staff Publications

Shallow, dominantly silt- and clay-filled erosional troughs in Quaternary sediments under the Flathead Valley (northwestern Montana, USA) are very likely to be hydraulic barriers limiting the horizontal flow of groundwater. Accurately mapping them is important because of increasing demand for groundwater.We used a legacy Bouguer gravity map measured in 1968. The directional derivatives of the map are computed, and the map was enhanced by implementing edge detection tools.We produced generalized derivative, maximum horizontal gradient, total gradient and tilt gradient maps through two-dimensional Fourier transform analysis. These maps were remarkably successful in locating buried troughs in the northern and northwestern parts …

Development Of The Quantitative Modelling Observation Protocol (Qmop) For Undergraduate Biology Courses: Validity Evidence For Score Interpretation And Uses, Lyrica Lucas, Anum Khushal, Robert Mayes, Brian Couch, Joseph Dauer

School of Natural Resources: Faculty Publications

Educational reform priorities such as emphasis on quantitative modelling (QM) have positioned undergraduate biology instructors as designers of QM experiences to engage students in authentic science practices that support the development of datadriven and evidence-based reasoning. Yet, little is known about how biology instructors adapt to the pedagogical movement towards incorporating QM opportunities for students in the courses they teach. This study presents the development of the Quantitative Modelling Observation Protocol (QMOP), a classroom observation instrument designed to support the need to characterise various approaches that instructors use to implement QM instruction in undergraduate biology. QMOP provides information about the …

Declining Pronghorn (Antilocapra Americana) Population Productivity Caused By Woody Encroachment And Oil And Gas Development, Victoria M. Donovan, Jeffrey L. Beck, Carissa L. Wonkka, Caleb P. Roberts, Craig R. Allen, Dirac L. Twidwell Jr

School of Natural Resources: Faculty Publications

Conservation is increasingly focused on preventing losses in species’ populations before they occur. Tracking changes in demographic parameters that can impact a population’s resilience in response to drivers of global change can support early conservation efforts. We assessed trends in population productivity (late summer juveniles per 100 females) relative to drivers of global change in 40 pronghorn (Antilocapra americana) herds across sagebrush (Artemisia spp.) steppe in Wyoming. Pronghorn are an iconic rangeland species that have been exposed to increasing levels of anthropogenic, climatic, and land-use change. Using data collected across the state of Wyoming, we (1) assessed …

Discussion On “Spatial+: A Novel Approach To Spatial Confounding” By Dupont, Wood, And Augustin, Brian J. Reich, Shu Yang, Yawen Guan

Department of Statistics: Faculty Publications

Congratulations to the authors for this thoughtful and timely contribution to the spatial confounding literature. The intuitive nature of the method and simplicity of the estimation procedure will surely make Spatial+ popular with practitioners, and the theoretical developments are a major advance for researchers in this area. There is much to discuss! We have formatted our discussion in two sections: in Section 2 we consider the assumptions and statistical properties of Spatial+, and in Section 3 we examine how Spatial+ fits in the wider literature on spatial causal inference.

Prebiotic Proanthocyanidins Inhibit Bile Reflux–Induced Esophageal Adenocarcinoma Through Reshaping The Gut Microbiome And Esophageal Metabolome, Katherine M. Weh, Connor L. Howard, Yun Zhang, Bridget A. Tripp, Jennifer Clarke, Amy B. Howell, Joel H. Rubenstein, Julian A. Abrams, Maria Westerhoff, Laura A. Kresty

Department of Statistics: Faculty Publications

The gut and local esophageal microbiome progressively shift from healthy commensal bacteria to inflammation-linked pathogenic bacteria in patients with gastroesophageal reflux disease, Barrett’s esophagus, and esophageal adenocarcinoma (EAC). However, mechanisms by which microbial communities and metabolites contribute to reflux-driven EAC remain incompletely understood and challenging to target. Herein, we utilized a rat reflux-induced EAC model to investigate targeting the gut microbiome–esophageal metabolome axis with cranberry proanthocyanidins (C-PAC) to inhibit EAC progression. Sprague-Dawley rats, with or without reflux induction, received water or C-PAC ad libitum (700 μg/rat/day) for 25 or 40 weeks. C-PAC exerted prebiotic activity abrogating reflux-induced dysbiosis and mitigating …

Command Injection Attacks In Smart Grids: A Survey, Muhammad Usama, Muhammad Naveed Aman

School of Computing: Faculty Publications

Cybersecurity is important in the realization of various smart grid technologies. Several studies have been conducted to discuss different types of cyberattacks and provide their countermeasures. The false command injection attack (FCIA) is considered one of the most critical attacks that have been studied. Various techniques have been proposed in the literature to detect FCIAs on different components of smart grids. The predominant focus of current surveys lies on FCIAs and detection techniques for such attacks. This article presents a survey of existing works on FCIAs and classifies FCIAs in smart grids according to the targeted component. The impacts of …

Unveiling The Connection Between Malware And Pirated Software In Southeast Asian Countries: A Case Study, Asif Iqbal, Muhammad Naveed Aman, Ramkumar Rejendran, Biplab Sikdar

School of Computing: Faculty Publications

Pirated software is an attractive choice for cybercriminals seeking to spread malicious software, known as malware. This paper attempts to quantify the occurrence of malware concealed within pirated software.We collected samples of pirated software from various sources from Southeast Asian countries, including hard disk drives, optical discs purchased in eight different countries, and online platforms using peerto- peer services. Our dataset comprises a total of 750 pirated software samples. To analyze these samples, we employed seven distinct antivirus (AV) engines. The malware identified by the AV engines was classified into four categories: adware, Trojans, viruses, and a miscellaneous category termed …

Experimental Sars-Cov-2 Infection Of Elk And Mule Deer, Stephanie M. Porter, Airn E. Hartwig, Helle Bielefeldt-Ohmann, Jeffrey M. Marano, J. Jeffrey Root, Angela M. Bosco-Lauth

United States Department of Agriculture Wildlife Services: Staff Publications

To assess the susceptibility of elk (Cervus canadensis) and mule deer (Odocoileus hemionus) to SARS-CoV-2, we performed experimental infections in both species. Elk did not shed infectious virus but mounted low-level serologic responses. Mule deer shed and transmitted virus and mounted pronounced serologic responses and thus could play a role in SARS-CoV-2 epidemiology.

Parallels Of Quantum Superposition In Ecological Models: From Counterintuitive Patterns To Eco-Evolutionary Interpretations Of Cryptic Species, David G. Angeler, Hannah B. Fried-Petersen

School of Natural Resources: Faculty Publications

Background Superposition, i.e. the ability of a particle (electron, photon) to occur in different states or positions simultaneously, is a hallmark in the subatomic world of quantum mechanics. Although counterintuitive at first sight, the quantum world has potential to inform macro-systems of people and nature. Using time series and spatial analysis of bird, phytoplankton and benthic invertebrate communities, this paper shows that superposition can occur analogously in redundancy analysis (RDA) frequently used by ecologists.

Results We show that within individual ecosystems single species can be associated simultaneously with different orthogonal axes in RDA models, which suggests that they operate in …

Factors Affecting Walleye And Sauger Recruitment In Lewis And Clark Lake, South Dakota, 2001–2022, William J. Radigan, Phil Chvala, Christopher Longhenry, Mark A. Pegg

School of Natural Resources: Faculty Publications

Abundance of adult walleye (Sander vitreus) and sauger (Sander canadensis), two important sport fishes, decreased significantly during 2001–2022 in Lewis and Clark Lake, a border water between Nebraska and South Dakota, despite walleye fingerling stocking and stable age-0 abundance of both species. We sought to identify factors that drove variation in age-0 abundance from 2001 to 2022 using an information theoretic approach. Age-0 walleye catch per unit effort (CPUE) was correlated to mean monthly outflow, mean annual precipitation, and mean April gauge height in a delta. Age-0 sauger CPUE was correlated to adult conspecific CPUE, mean …

Program Requirements For Beef Cattle Certified As Usda Organic, Carsten Loseke, Elliott James Dennis

Cornhusker Economics

This document provides an overview of the use and production of the USDA Certified Organic program for the beef cattle industry, with an emphasis on the state of Nebraska. We detail what cattle qualify, feed requirements, medical and health standards of cattle, and premiums paid by consumers for USDA certified organic products. All information is taken from the Organic Foods Production Act Provisions available in the Federal Register.

Estimation Of Sugarcane Yield Using Multi-Temporal Sentinel 2 Satellite Imagery And Random Forest Regression, Alireza Taravat, Gebeyehu Abebe, Berhan Gessesse, Tsegaye Tadesse

National Drought Mitigation Center: Faculty Publications

Advancements in remote sensing techniques have greatly enhanced crop monitoring and yield estimation, with spectral vegetation indices (VIs) serving as a key component. Our study investigates the use of Sentinel-2 data, notable for its red-edge bands, in estimating sugarcane yield in Ethiopia's Awash Basin. Utilizing 22 VIs from S2 imagery, our approach combines Random Forest (RF) regression with the Recursive Feature Elimination (RFE) algorithm to improve the accuracy of sugarcane yield predictions. The results demonstrate the superior performance of the RF-RFE method over traditional RF with full datasets and Stepwise Multiple Regression (SMR). Particularly, VIs focusing on the red-edge spectral …

Habitat Characteristics, Distribution, And Abundance Of Cicindelidia Haemorrhagica (Leconte) (Coleoptera: Cicindelidae) In Yellowstone National Park, K. A. Willemssens, J. L. Bowley, L. Cavallini, E. Oberg, R.K.D. Peterson, Leon G. Higley

School of Natural Resources: Faculty Publications

No abstract provided.

Dynamic Rates Of Freshwater Drum Near The Northern Extent Of Their Range: Evidence Of Environment-Recruitment Relationships, M. Stuart, N. Kludt, M. A. Pegg, F. Montesanto, C. Lyon, C. J. Chance-Ossowski

School of Natural Resources: Faculty Publications

No abstract provided.

High-Altitude Adaptation Is Accompanied By Strong Signatures Of Purifying Selection In The Mitochondrial Genomes Of Three Andean Waterfowl, A. M. Graham, P. Lavretsky, R. E. Wilson, K. G. Mccracken

School of Natural Resources: Faculty Publications

No abstract provided.

Long-Term Croplands Water Productivity In Response To Management And Climate In The Western Us Corn Belt, M. Khorchani, Tala Awada, M. Schmer, V. Jin, G. Birru, S.R.S. Dangal, Andrew E. Suyker, A. Freidenreich

School of Natural Resources: Faculty Publications

No abstract provided.

Current Challenges And Future Of Agricultural Genomes To Phenomes In The Usa, C. K. Tuggle, J. L. Clarke, B. M. Murdoch, E. Lyons, N. M. Scott, B. Benes, J. D. Campbell, H. Ching, C. L. Daigle, S. D. Choudhury, J.C. M. Dekkers, J.R.R. Dorea, D. S. Erti, B. O. Fragomeni, J. E. Fulton, C. R. Guadagno, D. E. Hagen, A. S. Hess, L. M. Kramer, C. J. Lawrence-Dill, A. E. Lipka, T. Lubberstedt, F. M. Mccarthy, P. S. Schnable

School of Natural Resources: Faculty Publications

No abstract provided.

15-Yr Biomass Production In Semiarid Nebraska Sandhills Grasslands: Part 1—Plant Functional Group Analysis, B. Zhao, B. M. Stephenson, T. Awada, J. Volesky, B. Wardlow

School of Natural Resources: Faculty Publications

No abstract provided.

Identifying Untapped Legal Capacity To Promote Multi‑Level And Cross‑Sectoral Coordination Of Natural Resource Governance, Nicola Harvey, Ahjond Garmestani, Craig R. Allen, Anoeska Buijze, Marleen Van Rijswick

School of Natural Resources: Faculty Publications

Natural resource governance in the face of climate change represents one of the seminal challenges of the Anthropocene. A number of innovative approaches have been developed in, among others, the fields of ecology, governance, and sustainability sciences for managing uncertainty and scarcity through a coordinated approach to natural resource governance. However, the absence of an enabling legal and regulatory framework has been identified in the literature as one of the primary barriers constraining the formal operationalization of these governance approaches. In this paper, we show how these approaches provide tools for analyzing procedural mandates across governmental levels and sectors in …