Digital Commons Network^™

Intestinal Gas Production By The Gut Microbiota: A Review, Erasme Mutuyemungu, Mukti Singh, Sean Liu, Devin J. Rose

Department of Food Science and Technology: Faculty Publications

In addition to causing embarrassment, intestinal gas can be associated with more serious symptoms. This review provides an overview of gas production by the human gut microbiome and outlines foods associated with intestinal gas. Bacteroides, Ruminococcus, Roseburia, Clostridium, Eubacterium, Desulfovibrio, and Methanobrevibacter are among the most abundant microbes responsible for intestinal gas. More than 99% of intestinal gas is composed of hydrogen, carbon dioxide, and methane, while less than 1% is composed of other odiferous compounds. Food groups associated with intestinal gas include pulses, vegetables, fruits, grains, and, for some individuals, dairy. These foods are …

Demographic Groups Differ In Urban Recreational Behavior, Brandon Barlow

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

Urban recreational behavior is an essential component to understanding both how our recreational opportunities will be utilized and how they can be further improved. By improving recreational opportunities, we can ensure safe and reliable emotional and physical outlets for users. As urban areas continue to expand both in geographic area and in population size, urban recreational opportunities will also see growth in the number of recreational users. Demographics provide the opportunity to further understand and predict recreational behavior, producing a variety of decision management tools. Our goal was to understand differences in urban recreational behavior among demographic groups. To address …

Antimicrobial Efficacy Of A Citric Acid/Hydrochloric Acid Blend, Peroxyacetic Acid, And Sulfuric Acid Against Salmonella On Inoculated Non-Conventional Raw Chicken Products, Emma Nakimera

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

The utilization of non-conventional chicken parts as human food varies widely across countries. The high prevalence of Salmonella, especially in the giblets, poses a high risk to public health. Poultry processors have implemented multiple hurdle technology to reduce this gram-negative pathogen in chicken parts. This study was conducted to evaluate the antimicrobial efficacy of a commercial blend of citric acid/ hydrochloric acid (CP), peroxyacetic acid (PAA), and sulfuric acid (SA) in reducing Salmonella inoculated on two chicken giblets: livers and hearts. Chicken hearts and livers were inoculated (6 log CFU/ml of rinsate) by individually immersing them in a cocktail …

Semantic Segmentation Based Deep Learning Approaches For Weed Detection, Puranjit Singh

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

Global increase in herbicide use to control weeds has led to issues such as evolution of herbicide-resistant weeds, off-target herbicide movement, etc. Precision agriculture advocates Site Specific Weed Management (SSWM) application to achieve precise and right amount of herbicide spray and reduce off-target herbicide movement. Recent advancements in Deep Learning (DL) have opened possibilities for adaptive and accurate weed recognitions for field based SSWM applications with traditional and emerging spraying equipment; however, challenges exist in identifying the DL model structure and train the model appropriately for accurate and rapid model applications over varying crop/weed growth stages and environment. In our …

Timing Of Implants Use In Backgrounding System, Kylie M. Butterfield

Applied Science Program: Theses

A study was conducted over two years to determine the interactions of winter rate of gain at a high gain (HG) of 0.91 kg and low gain (LG) 0.45 kg, and implant strategy in the backgrounding and subsequent effects in the finishing phases. There were three phases in this study, the winter phase (~148 days), the summer phase (~60 days) and the finishing phase (~120 days). This was a 2 x 3 factorial design. The first factor is a rate of gain at either 0.91 kg (HG) or 0.45 kg (LG). The next factor is the timing of implant where …

Quantifying The Relationship Between Soil Organic Carbon And Soil Color In Nebraska, Aldi J. Airori

Applied Science Program: Theses

Soil color is easily measured in the field and holds potential to be used as an indirect measurement of soil organic carbon (SOC). The main limitation to this approach is knowledge about the specific color-SOC relationship in a region, which often varies in relation to parent material, soil texture, climate, and land use. Furthermore, the Munsell color data is subjective in nature. The objectives of this study are: 1) to develop and evaluate the accuracy of pedotransfer functions (PTFs) for the prediction of SOC based on soil color and texture in the state of Nebraska and 2) to evaluate digital …

Eco-Dystopian Novels Written By Women: Second, Third, And Fourth Wave Feminism, Trystyn Cox

Department of Environmental Studies: Undergraduate Student Theses

The project is thematic; analysis of eco-dystopian novels written by American female authors in the 20th and 21st centuries in order to determine if the different waves of feminism experienced in the United States had any influence over the books. By doing an analysis of eco-dystopian novels the study identifies if there were any outside societal movements or issues going on at the time that may have influenced how the book was created or if a particular book was able to open innovative ideas to the society at the time it was published. I researched the second, third, and fourth …

Nitrification Inhibitor, Nitrogen Source, And Herbicide Effects On Soil Nitrogen Transformations And Corn Yield, William Neels

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

Nitrogen fertilizer management continue to be challenging due to potential nitrogen losses under variable weather conditions. The objective of this was to evaluate the performance of nitrification inhibitors, nitrogen sources and herbicides on in-season nitrogen availability and agronomy indicators. A two site-year field experiment was conducted in silty clay loam soil in corn phase of the corn-soybean rotation at Central Nebraska. The treatments included three herbicide (no pre-emergence, Acuron, Resicore) and five nitrogen treatments: 1) control, 2) anhydrous ammonia, 3) anhydrous ammonia without nitrification inhibitor, 4) urea with nitrification inhibitors, and 5) urea without nitrification inhibitors. Results indicated that nitrogen …

Addressing Challenges Of Dryland Production Of Sunflowers And Corn In The Semi-Arid High Plains Of Nebraska, Zhan Orazov

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

Corn and sunflower are value crops for America. Cultivation of corn and sunflower often vary depending on growing environment. Selecting appropriate planting dates, hybrids and plant density frequently concerns farmers. This concern is understandable because the decision made directly impacts final income. The objectives were to evaluate interaction of corn and sunflower planting dates and hybrid maturity and evaluate interaction of corn flex hybrids and plant density under conditions of western Nebraska. Nine corn hybrids with relative maturity ranging from 86 to 105 days were sown between early May and late June in first and between late April and early …

Food Security & Urban Agriculture - Considerations For Soil Improvements And Crop Planning, Aaron Sedivy

Doctor of Plant Health Program: Dissertations and Student Research

Urban agriculture provides many benefits, such as energy conservation, rainwater remediation, increased aesthetic and property value, and therapeutic use for physical, cognitive, and emotional wellbeing. Urban agriculture can also provide critical integrity to each pillar of food security: availability, access, utilization, and stability. As urban agricultural activities increase, social interactions will follow in concert. This will provide opportunities for building trust through the two-way communication of contrasting perspectives, cultures, and beliefs using impartial narratives. Growers can use knowledge and understanding gained from these positive social interactions to formulate their personal paradigms for practice and better meet the needs of each …

Adverse Health Impacts On Honey Bee (Apis Mellifera L.) Colonies From A Contaminated Environment And Resources, Rogan Tokach

Department of Entomology: Dissertations, Theses, and Student Research

Honey bees (Apis mellifera L.) continue to experience high annual declines due to a combination of factors including pesticides. Due to increasing agricultural intensification has led to a reliance on systemic pesticide treated seed which can brought back to the colony in pollen and nectar. Treated seed is not subject to the same guidelines as pesticide applications reducing the regulations on the disposal of treated seed. In 2015, an ethanol plant in Mead, Nebraska began processing expired treated seed for ethanol production. Subsequently, the University of Nebraska-Lincoln Bee Lab started seeing 100% colony failure in apiaries surrounding the plant. …

Evaluating The Efficacy Of Germination And Fermentation In Producing Biologically Active Peptides From Pulses, Ashley Newton

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

Recently, there has been a profound increase in demand of plant-based proteins, especially pulse proteins. However, pulses contain high concentrations of antinutritional factors that hinder the digestibility of proteins. Processing techniques such as enzymatic hydrolysis, microbial fermentation, and physical processing modulate nutritional quality and functionality of pulses. Processing also releases peptides from parent proteins that exhibit health-beneficial bioactivity against various disease risk factors. In this study, germination, gastrointestinal digestion, and microbial fermentation were evaluated to determine the nutritional quality and release of bioactive peptides during and after processing.

Germination of chickpeas (Cicer arietinum L.) modulated the protein profile, and …

Comparative Genomics Of Five Valsa Species Gives Insights On Their Pathogenicity Evolution, Guangchao Sun, Shichang Xie, Lin Tang, Chao Zhao, Mian Zhang, Lili Huang

Department of Agronomy and Horticulture: Faculty Publications

Valsa is a genus of ascomycetes within the Valsaceae family. This family includes many wood destructive pathogens such as the well known Valsa mali and Valsa pyri which cause canker diseases in fruit trees and threaten the global fruit production. Lack of genomic information of this family is impeding our understandings about their evolution and genetic basis of their pathogenicity divergence. Here, we report genome assemblies of Valsa malicola, Valsa persoonii, and Valsa sordida which represent close relatives of Valsa mali and Valsa pyri with different host preferences. Comparative genomics analysis revealed that segmental rearrangements, inversions, and translocations …

Food Waste, Preference, And Cost: Perceived Barriers And Self-Reported Food Service Best Practices In Family Child Care Homes, Divya Patel, Daisy Butzer, Bethany D. Williams, Dipti Dev, Diane Horm, Denise Finneran, Bryce Lowery, Janis E. Campbell, Susan B. Sisson

Department of Child, Youth, and Family Studies: Faculty Publications

Background: Family Child Care Homes (FCCHs) are a setting where providers care for children at their own residence. FCCHs face unique challenges, and children may not always receive optimal nutrition and have higher risk of obesity compared to other programs. The objective of this study was to determine differences in food service best practices scores between FCCHs who did/did not perceive barriers to serving healthy meals. Methods: FCCHs (n = 167) self-reported demographics and perceived barriers to serving healthy foods. Nutrition and Physical Activity Self-Assessment for Child Care was used to assess food served with 1 (indicating poor practice) …

Comparative Genome Analysis Of Plant Ascomycete Fungal Pathogens With Different Lifestyles Reveals Distinctive Virulence Strategies, Yansu Wang, Jie Wu, Jiacheng Yan, Ming Guo, Lei Xu, Liping Hou, Quan Zou

Department of Agronomy and Horticulture: Faculty Publications

Background: Pathogens have evolved diverse lifestyles and adopted pivotal new roles in both natural ecosystems and human environments. However, the molecular mechanisms underlying their adaptation to new lifestyles are obscure. Comparative genomics was adopted to determine distinct strategies of plant ascomycete fungal pathogens with different lifestyles and to elucidate their distinctive virulence strategies. Results: We found that plant ascomycete biotrophs exhibited lower gene gain and loss events and loss of CAZyme-encoding genes involved in plant cell wall degradation and biosynthesis gene clusters for the production of secondary metabolites in the genome. Comparison with the candidate effectome detected distinctive variations between …

Molecular Mechanisms Underlying Aberrant Circulating Steroid Hormones In Gnrhr-Ii Knockdown Boars And Their Control Littermates, Dorothy H. Elsken

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

Swine are the only livestock species that produce a functional protein for both GnRH-II and its receptor (GnRHR-II). Our laboratory reported that the interaction between GnRH-II and GnRHR-II facilitates testosterone production, independent of LH stimulation. To further examine GnRHR-II function, we developed a swine line with 70% reduced GnRHR-II mRNA levels (GnRHR-II KD) compared to control littermates. Mass spectrometry analysis of serum revealed that circulating levels of gonadal steroids were reduced in mature transgenic vs. control boars. Paradoxically, evaluation of testicular tissue indicated no difference between lines for gonadal steroid hormone levels. To address a potential cause for this discrepancy, …

Impacts Of Feeding Biochar To Beef Cattle On Greenhouse Gas Emissions And Performance And Characterizing Yearling Steers Grazing Smooth Bromegrass Pasture Using Gps, Holly A. Heil

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

As global warming continues to rise, the pressure and growing demand for sustainable animal production is increasing. Livestock naturally produce greenhouse gas emissions through enteric fermentation. Dietary manipulation strategies have been sought out to decrease emissions in ruminants using feed additives.

Two independent finishing feedlot experiments evaluated two types of biochar and its effects on animal performance, carcass characteristics and greenhouse gas emissions. Experiment 1 utilized pistachio shell biochar and experiment 2 utilized biochar sourced from ponderosa pine wood waste, both types included at 1% of the diet DM. The addition of biochar to the diet did not impact animal …

The Nebraska 4-H Equine Advancement Level Program’S Role In Positive Youth Development Using The Five Cs Model: An Exploratory Study, Eunhye Mccarthy

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

Positive youth development (PYD) focuses on developing the strengths of youth through positive activities and behaviors rather than reducing negative tendencies. A well-researched model of PYD is the five C’s model that is popularly used in youth development organizations such as 4-H. The Nebraska 4-H Equine Advancement Level program was intended to serve as a guidebook for instruction and assessment of youth as they learn more about horses and horsemanship skills. Each of the four levels has an emphasis in developing a 4-H member’s responsibility, self-discipline, self-reliance, patience, and pride of accomplishments. The program was started approximately 30 years ago …

Environmental Determination Of Gastrointestinal Parasitism In Katahdin Sheep, Brian Arisman

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

Gastrointestinal nematodes (GIN) negatively affect the performance and wellbeing of sheep and are difficult to control due to anthelmintic resistance. Producers are therefore choosing breeds naturally resistant to GIN infection, such as the Katahdin. Katahdin are raised in various climates and management systems in the U.S., and those environmental factors can be combined into eco-management clusters. We hypothesized that GIN challenge varies predictably based on the characteristics of these clusters. Katahdin producers from across the U.S. were surveyed for management information. Body weights (BW), fecal egg counts (FEC) and FAMACHA scores (FAM) were collected on 3,527 Katahdin lambs around 90 …

Evaluation Of Nutritional Factors Affecting Sow Reproductive Longevity, J'Nan E. Wittler

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

Sow reproductive longevity is an important trait for swine operations from a production and economic standpoint. Previous research has shown that a sow needs to produce 3 litters before she covers the costs associated with introducing her to the operation. A literature review of research conducted related to sow longevity is discussed in Chapter 1. Chapters 2 and 3 present data from the University of Nebraska – Lincoln’s long-term sow longevity research. The research looks at the effects of energy restriction with soy hulls during gilt development on sow reproductive longevity through 4 parities. Chapter 2 presents data from replications …

Students' Perceptions Of Online Equine Courses And Their Impacts On Learning Outcomes, Blaire L. (Gibbens) Speck

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

Post-secondary education is always changing and evolving. Over the last few years, significant changes in education have resulted in an increased number of online courses. Approximately 28% of students seeking higher education participate in at least one online course and 14% are enrolled exclusively in distance or online programs (Allen & Seaman, 2016). However, courses that are typically hands-on, like equine science, may be more challenging online. The hands-on experiences in equine science classes help prepare students for future careers. Due to an increase in students choosing to take courses online, a review of online teaching methods was conducted to …

Evaluation Of The Effects Of Pine-Sourced Biochar On Cattle Performance And Methane And Carbon Dioxide Production From Growing And Finishing Steers, J. L. Sperber, B. C. Troyer, Galen E. Erickson, Andrea K. Watson

Department of Animal Science: Faculty Publications

A feedlot growing (77-d) and finishing (111-d) experiment was conducted to evaluate the effects of feeding biochar on steer performance, methane and carbon dioxide emissions, and carcass characteristics. Two treatments were evaluated, a control diet without biochar and the same diet with biochar included at 0.8% of dietary DM (growing) or 1.0% of dietary DM (finishing). The growing diet consisted of 40% corn silage, 40% wheat straw, 15% modified distillers grains plus solubles, and 5% supplement, with 0.8% biochar replacing fine ground corn in supplement. The finishing diet consisted of 55% high-moisture corn (HMC), 35% Sweet Bran, 5% wheat straw, …

Predicting Personalized Responses To Dietary Fiber Interventions: Opportunities For Modulation Of The Gut Microbiome To Improve Health, Car Reen Kok, Devin J. Rose, Robert Hutkins

Department of Nutrition and Health Sciences: Faculty Publications

Inadequate dietary fiber consumption has become common across industrialized nations, accompanied by changes in gut microbial composition and a dramatic increase in chronic metabolic diseases.The human gut microbiome harbors genes that are required for the digestion of fiber, resulting in the production of end products that mediate gastrointestinal and systemic benefits to the host. Thus, the use of fiber interventions has attracted increasing interest as a strategy to modulate the gut microbiome and improve human health. However, considerable interindividual differences in gut microbial composition have resulted in variable responses toward fiber interventions. This variability has led to observed nonresponder individuals …

Acafinder: Genome Mining For Anti-Crispr-Associated Genes, Bowen Yang, Jinfang Zheng, Yanbin Yin

Food for Health: Publications

Anti-CRISPR (Acr) proteins are encoded by (pro)viruses to inhibit their host’s CRISPR-Cas systems. Genes encoding Acr and Aca (Acr associated) proteins often colocalize to form acr-aca operons. Here, we present AcaFinder as the first Aca genome mining tool. AcaFinder can (i) predict Acas and their associated acr-aca operons using guilt-by-association (GBA); (ii) identify homologs of known Acas using an HMM (Hidden Markov model) database; (iii) take input genomes for potential prophages, CRISPR-Cas systems, and self-targeting spacers (STSs); and (iv) provide a standalone program (https://github.com/boweny920/AcaFinder) and a web server (http://aca .unl.edu/Aca). AcaFinder was applied to mining over …

Green Genius, Zoe Zingler

Honors Program: Expanded Learning Clubs

No abstract provided.

Life History And Ecology Of The San Emigdio Blue Butterfly (Lepidoptera: Lycaenidae), Gregory R. Ballmer

The Taxonomic Report of the International Lepidoptera Survey

The San Emigdio blue butterfly, Plebulina emigdionis (Grinnell, 1905), occurs in small, scattered colonies in and near the southwestern Mojave Desert of California. Colonies depend on a symbiotic relationship with the ant Formica francoueri (Bolton), and occur only where the ant’s range (primarily in more mesic cis-montane habitats) narrowly overlaps that of the butterfly’s more widely distributed Atriplex larval hosts in more xeric habitats. Colonies of P. emigdionis are often localized around a few host plants and, therefore, sensitive to habitat changes due to anthropocentric causes and environmental stochasticity. The biology, ecology, and status of known colonies of P emigdionis …

Bison Movements Change With Weather: Implications For Their Continued Conservation In The Anthropocene, Nicholas A. Mcmillan, Samuel D. Fuhlendorf, Barney Luttbeg, Laura E. Goodman, Craig A. Davis, Brady W. Allred, Robert G. Hamilton

Department of Agronomy and Horticulture: Faculty Publications

Animal movement patterns are affected by complex interactions between biotic and abiotic landscape conditions, and these patterns are being altered by weather variability associated with a changing climate. Some animals, like the American plains bison (Bison bison L.; hereafter, plains bison), are considered keystone species, thus their response to weather variability may alter ecosystem structure and biodiversity patterns. Many movement studies of plains bison and other ungulates have focused on point-pattern analyses (e.g., resource-selection) that have provided information about where these animals move, but information about when or why these animals move is limited. For example, information surrounding the …

The Genome Of Orychophragmus Violaceus Provides Genomic Insights Into The Evolution Of Brassicaceaepolyploidizationandits Distinct Traits, Kang Zhang, Yinqing Yang, Xin Zhang, Lingkui Zhang, Yu Fu, Zhongwei Guo, Shumin Chen, Jian Wu, James C. Schnable, Keke Yi, Xiaowu Wang, Feng Cheng

Department of Agronomy and Horticulture: Faculty Publications

Orychophragmus violaceus, referred to as ‘‘eryuelan’’ (February orchid) in China, is an early-flowering ornamental plant. The high oil content and abundance of unsaturated fatty acids in O. violaceus seeds make it a potential high-quality oilseed crop. Here, we generated a whole-genome assembly for O. violaceus using Nanopore and Hi-C sequencing technologies. The assembled genome of O. violaceus was ~1.3 Gb in size, with 12 pairs of chromosomes. Through investigation of ancestral genome evolution, we determined that the genome of O. violaceus experienced a tetraploidization event from a diploid progenitor with the translocated proto-Calepineae karyotype. Comparisons between the reconstructed subgenomes …

Piglet Cardiopulmonary Bypass Induces Intestinal Dysbiosis And Barrier Dysfunction Associated With Systemic Inflammation, Jeffrey D. Salomon, Haowen Qiu, Dan Feng, Jacob Owens, Ludmila Khailova, Suzanne Osorio Lujan, John Iguidbashian, Yashpal S. Chhonker, Daryl J. Murry, Jean-Jack Riethoven, Merry L. Lindsey, Amar B. Singh, Jesse A. Davidson

Nebraska Center for Biotechnology: Faculty and Staff Publications

The intestinal microbiome is essential to human health and homeostasis, and is implicated in the pathophysiology of disease, including congenital heart disease and cardiac surgery. Improving the microbiome and reducing inflammatory metabolites may reduce systemic inflammation following cardiac surgery with cardiopulmonary bypass (CPB) to expedite recovery postoperatively. Limited research exists in this area and identifying animal models that can replicate changes in the human intestinal microbiome after CPB is necessary. We used a piglet model of CPB with two groups, CPB (n=5) and a control group with mechanical ventilation (n=7), to evaluate changes to the microbiome, …

Spatiotemporal Metabolic Network Models Reveal Complex Autotroph-Heterotroph Biofilm Interactions Governed By Photon Incidences, Poonam Phalak, Hans C. Bernstein, Stephen R. Lindemann, Ryan S. Renslow, Dennis G. Thomas, Michael A. Henson, Hyun-Seob Song

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Autotroph-heterotroph interactions are ubiquitous in natural environment and play a key role in controlling various essential ecosystem functions, such as production and utilization of organic matter, cycling of nitrogen, sulfur, and other chemical elements. Understanding how these biofilm metabolic interactions are constrained in space and time remains challenging because fully predictive models designed for this purpose are currently limited. Toward filling this gap, here we developed community metabolic network models for two autotroph-heterotroph biofilm consortia (termed UCC-A and UCC-O), which share a suite of common heterotrophic members but have a single distinct photoautotrophic cyanobacterium (Phormidesmis priestleyi str. ANA and …