Digital Commons Network^™

Updated Threshold Dose-Distribution Data For Sesame, Paul J. Turner, Magdalena Gretzinger, Nandinee Patel, Helen A. Brough, R. Sharon Chinthrajah, Motohiro Ebisawa, Arnon Elizur, Jennifer J. Koplin, Rachel L. Peters, Natasha Purington, Anna Nowak-Wegrzyn, Sarah Saf, Hugh A. Sampson, Joost Westerhout, W. Marty Blom, Joseph L. Baumert, Geert F. Houben, Benjamin C. Remington

Department of Food Science and Technology: Faculty Publications

Sesame is classified as a “major” food allergen for which mandatory disclosure is required. Understanding reaction thresholds and how these vary within the allergic population is crucial in providing appropriate dietary advice to patients, providing guidance to the food industry, and informing dosing regimens for oral food challenges (FC). However, the largest data series used to derive a threshold dose-distribution for sesame included blinded challenge data from just 40 individuals.¹ Data from low-dose, open FC can be used to supplement that from blinded FC, reducing uncertainty in estimating threshold dose-distributions for allergenic foods which otherwise lack sufficient data.^{2 …}

Genomic Approaches To Uncovering The Coevolutionary History Of Parasitic Lice [Review], Kevin P. Johnson

Harold W. Manter Laboratory of Parasitology: Library Materials

Next-generation sequencing technologies are revolutionizing the fields of genomics, phylogenetics, and population genetics. These new genomic approaches have been extensively applied to a major group of parasites, the lice (Insecta: Phthiraptera) of birds and mammals. Two louse genomes have been assembled and annotated to date, and these have opened up new resources for the study of louse biology. Whole genome sequencing has been used to assemble large phylogenomic datasets for lice, incorporating sequences of thousands of genes. These datasets have provided highly supported trees at all taxonomic levels, ranging from relationships among the major groups of lice to those among …

Predicting Spatial-Temporal Patterns Of Diet Quality And Large Herbivore Performance Using Satellite Time Series, Sean P. Kearney, Lauren M. Porensky, David J. Augustine, Justin D. Derner, Feng Gao

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

Adaptive management of large herbivores requires an understanding of how spatial-temporal fluctuations in forage biomass and quality influence animal performance. Advances in remote sensing have yielded information about the spatial-temporal dynamics of forage biomass, which in turn have informed rangeland management decisions such as stocking rate and paddock selection for free-ranging cattle. However, less is known about the spatial-temporal patterns of diet quality and their influence on large herbivore performance. This is due to infrequent concurrent ground observations of forage conditions with performance (e.g., mass gain), and previously limited satellite data at fine spatial and temporal scales. We combined multi-temporal …

Counting Butterflies In Yosemite: A Guide For Beginners, Christine Melvin

Department of Entomology: Distance Master of Science Projects

Entomology is the study of insects. Insects are the most numerous animal group on the planet and therefore the field of entomology is further divided based upon insect groups. Butterflies and Moths belong to the insect group Lepidoptera. An entomologist who studies butterflies and/or moths is called a Lepidopterist. Butterflies are a special group of insects because they are not only studied by entomologists, but they are also studied by people called citizen scientists. Citizen science is the casual participation in gathering of data about anything relating to science. Anyone who uses the app iNaturalist is a citizen scientist because …

U.S. State Policy Contexts And Physical Health Among Midlife Adults, Blakelee R. Kemp, Jacob M. Grumbach, Jennifer Karas Montez

Department of Sociology: Faculty Publications

This study examines how state policy contexts may have contributed to unfavorable adult health in recent decades. It merges individual-level data from the 1993–2016 Behavioral Risk Factor Surveillance System (n=2,166,835) with 15 state-level policy domains measured annually on a conservative to liberal continuum. We examined associations between policy domains and health among adults ages 45–64 years and assess how much of the associations is accounted by adults’ socioeconomic, behavioral/lifestyle, and family factors. A more liberal version of the civil rights domain was associated with better health. It was disproportionately important for less-educated adults and women, and its association with adult …

Sustainability Around The World, Haley Withuhn, Ethan Halman Gonzalez

Honors Program: Expanded Learning Clubs

No abstract provided.

Comparison Of Methods To Estimate Ruminal Degradation And Intestinal Digestibility Of Protein In Hydrolyzed Feather Meal With Or Without Blood, Kassidy Buse, D. L. Morris, H. L. Diaz, O. R. Drehmel, Paul J. Kononoff

Department of Animal Science: Faculty Publications

Hydrolyzed feather meal (HFM) is a feedstuff high in rumen undegraded protein (RUP) that can be used as an effective source of metabolizable protein for dairy cattle. Because the production process may vary, the rumen degradability and intestinal digestibility of HFM may also vary. Additionally, some processes may incorporate additional blood into the final product to result in feather meal with poultry blood. To determine the rumen degradability and intestinal digestibility of these products, several laboratory assays can be used; the common assays are the mobile bag (MOB), modified three-step (MTS), and Ross (ROS) assays. Although all 3 assays determine …

Inflammatory Mediation Of Heat Stress-Induced Growth Deficits In Livestock And Its Potential Role As A Target For Nutritional Interventions: A Review, Micah S. Most, Dustin T. Yates

Department of Animal Science: Faculty Publications

Heat stress is detrimental to well-being and growth performance in livestock, and systemic inflammation arising during chronic heat stress contributes to these poor outcomes. Sustained exposure of muscle and other tissues to inflammation can impair the cellular processes that facilitate muscle growth and intramuscular fat deposition, thus reducing carcass quality and yield. Climate change is expected to produce more frequent extreme heat events, increasing the potential impact of heat stress on sustainable livestock production. Feedlot animals are at particularly high risk for heat stress, as confinement limits their ability to seek cooling from the shade, water, or breeze. Economically practical …

A Review Of Transformative Strategies For Climate Mitigation By Grasslands, Nuria Gomez-Casanovas, Elena Blanc-Betes, Caitlin E. Moore, Carl J. Bernacchi, Ilsa Kantola, Evan H. Delucia

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

Grasslands can significantly contribute to climate mitigation. However, recent trends indicate that human activities have switched their net cooling effect to a warming effect due to management intensification and land conversion. This indicates an urgent need for strategies directed to mitigate climate warming while enhancing productivity and efficiency in the use of land and natural (nutrients, water) resources. Here, we examine the potential of four innovative strategies to slow climate change including: 1) Adaptive multi-paddock grazing that consists of mimicking how ancestral herds roamed the Earth; 2) Agrivoltaics that consists of simultaneously producing food and energy from solar panels on …

The Price Of Surviving On Adrenaline: Developmental Programming Responses To Chronic Fetal Hypercatecholaminemia Contribute To Poor Muscle Growth Capacity And Metabolic Dysfunction In Iugr-Born Offspring, Rachel L. Gibbs, Dustin T. Yates

Department of Animal Science: Faculty Publications

Maternofetal stress induces fetal programming that restricts skeletal muscle growth capacity and metabolic function, resulting in intrauterine growth restriction (IUGR) of the fetus. This thrifty phenotype aids fetal survival but also yields reduced muscle mass and metabolic dysfunction after birth. Consequently, IUGR-born individuals are at greater lifelong risk for metabolic disorders that reduce quality of life. In livestock, IUGR-born animals exhibit poor growth efficiency and body composition, making these animals more costly and less valuable. Specifically, IUGR-associated programming causes a greater propensity for fat deposition and a reduced capacity for muscle accretion. This, combined with metabolic inefficiency, means that these …

Evidence Of Western Corn Rootworm (Diabrotica Virgifera Virgifera Leconte) Field-Evolved Resistance To Cry3bb1 + Cry34/ 35ab1 Maize In Nebraska, Jordan D. Reinders, Emily E. Reinders, Emily Robinson, Bryan W. French, Lance J. Meinke

Department of Entomology: Faculty Publications

BACKGROUND: Western corn rootworm (WCR; Diabrotica virgifera virgifera) field-evolved resistance to transgenic maize expressing the Cry3Bb1 protein derived from Bacillus thuringiensis (Bt) has been confirmed across the United States Corn Belt. Although use of pyramided hybrids expressing Cry3Bb1 + Cry34/35Ab1 has increased in recent years to mitigate existing WCR Bt resistance, susceptibility of Nebraska WCR populations to this rootworm–Bt pyramid has not been assessed. Plant-based bioassays were used to characterize the susceptibility of WCR populations to Cry3Bb1 and Cry3Bb1 + Cry34/35Ab1 maize. Populations were collected from areas of northeastern Nebraska with a history of planting Bt maize that expressed …

Mechanical Overload-Induced Muscle-Derived Extracellular Vesicles Promote Adipose Tissue Lipolysis, Ivan J. Vechetti Jr, Bailey D. Peck, Yuan Wen, R Grace Walton, Taylor R. Valentino, Alexander P. Alimov, Cory M. Dungan, Douglas W. Van Pelt, Ferdinand Von Walden, Bjorn Alkner, Charlotte A. Peterson, John J. Mccarthy

Department of Nutrition and Health Sciences: Faculty Publications

How regular physical activity is able to improve health remains poorly understood. The release of factors from skeletal muscle following exercise has been proposed as a possible mechanism mediating such systemic benefits. We describe a mechanism wherein skeletal muscle, in response to a hypertrophic stimulus induced by mechanical overload (MOV), released extracellular vesicles (EVs) containing muscle-specific miR-1 that were preferentially taken up by epidydimal white adipose tissue (eWAT). In eWAT, miR-1 promoted adrenergic signaling and lipolysis by targeting Tfap2α, a known repressor of Adrβ3 expression. Inhibiting EV release prevented the MOV-induced increase in eWAT miR-1 abundance and expression of …

Novel Approaches For Enhancing Cell Survival And Function In Vivo, Ou Wang

Department of Chemical and Biomolecular Engineering: Dissertations, Theses, and Student Research

FDA has approved several cell-based therapeutics and hundreds of cell therapy clinical trials are ongoing. Cells will be a significant type of medicine after small molecule and protein drugs. However, several obstacles need to be addressed to achieve the widespread use of cellular therapeutics. The first challenge is the low efficacy of cell transplantation due to low retention, survival, integration, and function of cells in vivo. The second challenge is producing a massive number of cells for clinical treatment with cost-effectively and reproducibly technologies.

In this thesis, we proposed and investigated two approaches to address these challenges. To begin …

The Molecular Basis For Natural Competence In Acinetobacter, Yafan Yu

Department of Food Science and Technology: Dissertations, Theses, and Student Research

Bacteria use Horizontal Gene Transfer (HGT) to acquire genetic material, leading to the development of novel traits, such as the spread and development of antibiotic resistance. Natural competence is one type of HGT accomplished by DNA uptake from the environment and incorporation into the genome. Bacteria from Acinetobacter are wildly distributed in the environment and are naturally competent. This propensity is a key factor to the steady increase in drug resistance in Acinetobacter, which is a cause for concern in human health as Acinetobacter is a major source of nosocomial infections. During natural competence, type IV pili (T4P) and related …

The Application Of Mathematical Optimization And Flavor-Detection Technologies For Modeling Aroma Of Hops, Yutong Liu

Department of Food Science and Technology: Dissertations, Theses, and Student Research

In recent years, proprietary hops (Citra, Simcoe, and Mosaic) become the most sought-after hops among brewers due to their excellent aroma. However, they are restricted to the owners unless other growers purchase the costly licensing agreements. Many public hops are available to the growers without any additional costs, but their aroma is difficult to match to the proprietary hops. Although proprietary and public hop varieties are unique in their aroma profiles, all hops varieties contain similar volatile compounds, merely differ in the quantity of different individual compounds. The main objective of this thesis was to investigate the feasibility of matching …

Women And The Mealing Room: Presenting A Comparative Analysis Of Female Spaces Across The Chacoan Landscape, Olivia H. Thomsen

Department of Anthropology: Theses and Student Research

In the two papers presented in this thesis, I examine mealing facility architecture both within and beyond Chaco Canyon. Both ethnographic and archaeological evidence tie the secular and sacred action of grinding corn to the gendered labor of women in modern and Ancestral Pueblo societies. In both chapters I utilize the defining elements of context, scale, association, and access to measure the ways in which corn grinding facilities in various Chacoan sites are similar and dissimilar to one another.

In chapter 2, I examine the dichotomy between great and small houses located within Chaco Canyon regarding mealing facilities. Utilizing legacy …

Charting A New Frontier Integrating Mathematical Modeling In Complex Biological Systems From Molecules To Ecosystems, Katharine A. White, Kira D. Mcentire, Nicole R. Buan, Lecia Robinson, Elisar Barbar

Department of Biochemistry: Faculty Publications

Advances in quantitative biology data collection and analysis across scales (molecular, cellular, organismal, and ecological) have transformed how we understand, categorize, and predict complex biological systems. This surge of quantitative data creates an opportunity to apply, develop, and evaluate mathematical models of biological systems and explore novel methods of analysis. Simultaneously, thanks to increased computational power, mathematicians, engineers, and physical scientists have developed sophisticated models of biological systems at different scales. Novel modeling schemes can offer deeper understanding of principles in biology, but there is still a disconnect between modeling and experimental biology that limits our ability to fully realize …

Genetic Mapping And Qtl Analysis For Peanut Smut Resistance, Francisco J. De Blas, Cecilia I. Bruno, Renee Arias, Carolina Ballén-Taborda, Eva Mamani, Claudio Oddino, Melina Rosso, Beatriz P. Costero, Marina Bressano, Juan H. Soave, Sara J. Soave, Mario I. Buteler, J. Guillermo Seijo, Alicia Massa

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

Background: Peanut smut is a disease caused by the fungus Thecaphora frezii Carranza & Lindquist to which most commercial cultivars in South America are highly susceptible. It is responsible for severely decreased yield and no effective chemical treatment is available to date. However, smut resistance has been identified in wild Arachis species and further transferred to peanut elite cultivars. To identify the genome regions conferring smut resistance within a tetraploid genetic background, this study evaluated a RIL population {susceptible Arachis hypogaea subsp. hypogaea (JS17304-7-B) × resistant synthetic amphidiploid (JS1806) [A. correntina (K 11905) × A. cardenasii (KSSc 36015)] × A. …

Livestock Grazing Impacts On Crop And Soil Responses For Two Cropping Systems, Alyssa Kuhn

Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research

Diversified crop, forage, and livestock systems are assumed to be more sustainable and economically competitive than traditional cropping systems. Objectives of this study were to determine effects of integrating grazing livestock into corn (Zea mays)-soybean (Glycine max (L.) Merr.) (C-S) and corn-soybean-wheat (Triticum aestivum L.) (C-S-W) cropping systems on plant population, grain yield, soil nutrients and soil carbon dioxide (CO₂) flux following winter grazing corn residue (both systems) and an oat (Avena sativa) cover crop (C-S-W only) planted after wheat. For the 2019 and 2020 production seasons, neither corn nor soybean plant …

Statistical Mediation Analysis In Regression Discontinuity Design For Causal Inference, Donna Chen

College of Education and Human Sciences: Dissertations, Theses, and Student Research

Regression discontinuity designs (RDDs) are the most robust quasi-experimental design, but current statistical models are limited to estimates for the simple causal relationship between only two variables: the independent and dependent variables. In practice, intervening variables (or mediators) are often observed as part of the causal chain. Mediators explain the why and how a treatment or intervention works. Therefore, mediation and RDD analysis combined can be a useful tool in identifying key components or processes that make intervention programs effective while making causal inferences for improving student achievement, despite natural constraints, limitations, and ethical considerations. Without an integrated framework of …

Characterization Of The Multifunctional Enzyme Proline Utilization A, Yizi Mao

Department of Biochemistry: Dissertations, Theses, and Student Research

Proline is a unique and important amino acid. Proline is a proteogenic amino acid and its metabolism is involved in many critical cellular functions. Therefore, proline metabolism is tightly regulated, and dysfunction of proline metabolism is related to human diseases. The first step of proline oxidization to ∆¹-pyrroline-5-carboxylic acid (P5C) is catalyzed by proline dehydrogenase (PRODH). P5C is then non-enzymatically hydrolyzed to glutamate-γ-semialdehyde (GSA), which can be further oxidized to glutamate by P5C dehydrogenase (P5CDH/GSALDH). In Gram-negative bacteria, the PRODH and P5CDH enzymes are expressed as one polypeptide called proline utilization A (PutA). In some Gram-negative bacteria an …

Intricacies In Agronomic Management: The Role Of Interdisciplinary Education, Adam M. Striegel

Doctor of Plant Health Program: Dissertations and Student Research

As a science, agronomy is built upon the connection of inter-disciplinary fields of study. Management (M) of various discipline considerations (and their subsequent interactions) can be influenced by and have significant effects on genetic by environment (GxE) expression. This has led to the promotion of GxExM systems. However, optimizing GxExM programs requires extensive, interdisciplinary knowledge. To evaluate interdisciplinary training provided in undergraduate education, 11 four-year universities were selected in the United States that offer baccalaureate degree majors in agronomy or crop science. Surveys of undergraduate programs of study were conducted, with all required coursework separated into general degree components (general …

Distillers' Grains: Past, Present, And Future Economic Analyses, Daniel E. Gertner

Department of Agricultural Economics: Dissertations, Theses, and Student Research

This thesis is comprised of four chapters, each of which discusses or conducts economic research related to the distillers’ grains market. The first three chapters are meant to be standalone papers. Chapter four provides potential paths forward in distillers’ grains research based on the findings of the first three chapters and concludes the thesis.

The first chapter conducts a comprehensive literature review that categorizes and summarizes economic research on distillers’ grains products. This section shows how the physical market has moved beyond the current academic understanding of market products and structure. Existing research finds that traditional distillers’ grains products positively …

Evaluation Of A Novel Approach For Assessing Biological Activity In Agricultural Soils, Karla Melgar

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

Soil health is a key factor impacting soil resilience and fertility in crop production systems. Favorable soil physical and biological conditions facilitate plant nutrient absorption and nutrient cycling. Demonstrating to farmers the impacts and changes in soil biological activity under different soil management practices has been a challenge due to the limited availability of inexpensive tools for quantifying this component of soil health. The primary goal of this study was to present a simple and readily accessible tool for evaluating soil biological activity to promote the use of organic amendments in crop fields. Research plots were established in two studies …

Evidence Of Western Corn Rootworm (Diabrotica Virgifera Virgifera Leconte) Field-Evolved Resistance To Cry3bb1 + Cry34/35ab1 Maize In Nebraska, Jordan Reinders, Emily E. Reinders, Emily Robinson, Brian W. French, Lance J. Meinke

Department of Entomology: Faculty Publications

BACKGROUND: Western corn rootworm (WCR; Diabrotica virgifera virgifera) field-evolved resistance to transgenic maize expressing the Cry3Bb1 protein derived from Bacillus thuringiensis (Bt) has been confirmed across the United States Corn Belt. Although use of pyramided hybrids expressing Cry3Bb1 + Cry34/35Ab1 has increased in recent years to mitigate existing WCR Bt resistance, susceptibility of Nebraska WCR populations to this rootworm–Bt pyramid has not been assessed. Plant-based bioassays were used to characterize the susceptibility of WCR populations to Cry3Bb1 and Cry3Bb1 + Cry34/35Ab1 maize. Populations were collected from areas of northeastern Nebraska with a history of planting Bt maize that expressed Cry3Bb1 …

Deterring Non-Target Birds From Toxic Bait Sites For Wild Pigs, Nathan P. Snow, Joseph M. Halseth, Justin A. Foster, Michael J. Lavelle, Justin W. Fischer, Michael P. Glow, Ingrid A. Messer, Seth M. Cook, Kurt C. Vercauteren

United States Department of Agriculture Wildlife Services: Staff Publications

Toxic baiting of wild pigs (Sus scrofa) is a potential new tool for population control and damage reduction in the US. Field trials testing a prototype toxic bait (HOGGONE 2 containing 5% sodium nitrite [SN]), though, revealed that wild pigs spilled small particles of toxic bait outside of bait stations which subsequently created hazards for non-target species that consumed those particles, primarily passerine birds. To deter non-target birds from consuming particles of spilled bait, we tested four deterrents at mock bait sites (i.e., baited with bird seed) in north-central Colorado, USA during April–May 2020. We found a programable, inflatable deterrent …

Cardenolide, Potassium, And Pyrethroid Insecticide Combinations Reduce Growth And Survival Of Monarch Butterfly Caterpillars (Lepidoptera: Nymphalidae), Annie J. Krueger, Emily A. Robinson, Thomas J. Weissling, Ana M. Vélez, Troy D. Anderson

Department of Entomology: Faculty Publications

The monarch butterfly, Danaus plexippus L., has evolved to be insensitive to milkweed cardenolides via genetic modifications of Na⁺/K⁺-ATPase. There is concern for insecticide exposures near agriculture, with little information on monarch caterpillar toxicology. It is unclear how cardenolide insensitivity may affect the sensitivity of monarch caterpillars to pyrethroid insecticides. Additionally, potassium fertilizers may affect monarch caterpillar physiology and cardenolide sequestration. Here, we investigated the growth, survival, and development of caterpillars exposed to the cardenolide ouabain, bifenthrin, and potassium chloride (KCl) alone and in combination. Caterpillars were either exposed to (1) ouabain from third- to fifth-instar …

Reintegrating Biology Through The Nexus Of Energy, Information, And Matter, Kim L. Hoke, Sara L. Zimmer, Adam B. Roddy, Mary Jo Ondrechen, Craig E. Williamson, Nicole R. Buan

Department of Biochemistry: Faculty Publications

Information, energy, and matter are fundamental properties of all levels of biological organization, and life emerges from the continuous flux of matter, energy, and information. This perspective piece defines and explains each of the three pillars of this nexus. We propose that a quantitative characterization of the complex interconversions between matter, energy, and information that compose this nexus will help us derive biological insights that connect phenomena across different levels of biological organization. We articulate examples from multiple biological scales that highlight how this nexus approach leads to a more complete understanding of the biological system. Metrics of energy, information, …

Genetic Fingerprinting And Aflatoxin Production Of Aspergillus Section Flavi Associated With Groundnut In Eastern Ethiopia, Abdi Mohammed, Paola C. Faustinelli, Alemayehu Chala, Mashilla Dejene, Chemeda Fininsa, Amare Ayalew, Chris O. Ojiewo, David A. Hoisington, Victor S. Sobolev, Jaime Martínez-Castillo, Renee S. Arias

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

Background: Aspergillus species cause aflatoxin contamination in groundnut kernels, being a health threat in agricultural products and leading to commodity rejection by domestic and international markets. Presence of Aspergillus flavus and A. parasiticus colonizing groundnut in eastern Ethiopia, as well as presence of aflatoxins have been reported, though in this region, no genetic studies have been done of these species in relation to their aflatoxin production. Results: In this study, 145 Aspergillus isolates obtained from groundnut kernels in eastern Ethiopia were genetically fingerprinted using 23 Insertion/Deletion (InDel) markers within the aflatoxin-biosynthesis gene cluster (ABC), identifying 133 ABC genotypes. Eighty-four isolates …

Greenhouse Gas Emissions From Two Contrasting Beef Systems From Birth To Slaughter In Eastern Nebraska, Levi J. Mcphillips

Department of Animal Science: Dissertations, Theses, and Student Research

Over the last 15 years, the increase in land use for corn and soybean has come at the expense of acres of grasslands and perennial forages employed in conventional beef-production systems. Implementing alternative cow-calf production systems into existing cropping systems may be a solution for reduced land availability and reducing total greenhouse gas emissions (GHG). Therefore, GHG from a conventional (CONV) pasture-based cattle production system with cows wintered on corn residue and summer grazing of brome pasture were compared to partial-confinement system (ALT) with cows and calves in a drylot during the summer and grazing cover crops and corn residue …