Digital Commons Network^™

Characterization Of Arthropod Assemblages Attracted To Canine Feces Using Pitfall Traps And Rearing Experiments, Jennifer Albrecht

Department of Entomology: Distance Master of Science Projects

The decomposition of fecal matter is critical for an ecosystem, turning matter into a form that is usable by other organisms; the removal of feces also eliminates breeding sites for pests and prevents waste from entering waterways. The aim of this study was to survey arthropod populations that are attracted to dog feces in suburban and residential settings. Due to their established role in nutrient recycling, an emphasis was placed on identifying dung beetle species present. Monitoring was conducted in Lancaster County, Nebraska from July to September 2017 using pitfall traps and rearing experiments. It was hypothesized that southeast Nebraska …

Contextualizing The Relationship Between Culture And Puerto Rican Health: Towards A Place-Based Framework Of Minority Health Disparities, Giovani Burgos, Fernando I. Rivera, Marc A. Garcia

Department of Sociology: Faculty Publications

In both the culture of poverty literature and the acculturation literature, Puerto Ricans are portrayed in negative terms. The culture of poverty framework attributes Puerto Rican poverty to the mental, behavioral, and moral pathology of Puerto Rican individuals and to Puerto Rican culture. Similarly, outdated acculturation frameworks also trace the poor health of immigrants and racialized minorities, such as Puerto Ricans, to equivalent perceived deficiencies. In this paper, we argue that both the culture of poverty and acculturation frameworks are two pillars of the White Racial Frame (Feagin 2009) that sustains racial inequality in the United States. To build our …

Prediction Of Human Dietary Δ15N Intake From Standardized Food Records: Validity And Precision Of Single Meal And 24-H Diet Data, Frank Hülsemann, Karsten Koehler, Jürgen Wittsiepe, Michael Wilhelm, Annett Hilbig, Mathilde Kersting, Hans Braun, Ulrich Flenker, Wilhelm Schänzer

Department of Nutrition and Health Sciences: Faculty Publications

Natural stable isotope ratios (δ15N) of humans can be used for nutritional analyses and dietary reconstruction of modern and historic individuals and populations. Information about an individual’s metabolic state can be obtained by comparison of tissue and dietary δ¹⁵N. Different methods have been used to estimate dietary δ¹⁵N in the past; however, the validity of such predictions has not been compared to experimental values. For a total of 56 meals and 21 samples of 24-h diets, predicted and experimental δ¹⁵N values were compared. The δ¹⁵N values were predicted from self-recorded food intake …

Association Between Energy Balance And Metabolic Hormone Suppression During Ultra-Endurance Exercise, Bjoern Geesmann, Jenna C. Gibbs, Joachim Mester, Karsten Koehler

Department of Nutrition and Health Sciences: Faculty Publications

Ultra-endurance athletes often accumulate an energy deficit when engaging in ultra-endurance exercise, and upon completion of the exercise, they exhibit endocrine changes that are reminiscent of starvation. However, it remains unclear whether these endocrine changes are a result of the exercise per se or secondary to the energy deficit, and more importantly, whether these changes can be attenuated by increased dietary intake. Our goal was to assess the relationship between changes in key metabolic hormones following ultra-endurance exercise and measures of energy balance. Metabolic hormones as well as energy intake and expenditure were assessed in 14 well-trained male cyclists who …

Parental Views Of Promoting Fruit And Vegetable Intake Among Overweight Preschoolers And School-Aged Children, Martha J. Nepper, Weiwen Chai

Department of Nutrition and Health Sciences: Faculty Publications

Given the importance of parental influence on children’s eating habits, we explored perceptions of parents of overweight (body mass index–for-age percentile ≥85%) preschoolers (3-5 years) and overweight school-aged children (6-12 years) regarding challenges in promoting fruit and vegetable intake and how they and other family members influence their overweight children’s dietary habits. Focus groups were conducted with 13 parents of overweight preschoolers and 14 parents of overweight school-aged children. Codes and themes were developed by inductive data analysis. Four common themes were identified: short shelf life of fresh fruits and vegetables prohibiting parents from purchasing, children’s taste changes in fruits …

Web-Based Interventions Alone Or Supplemented With Peer-Led Support Or Professional Email Counseling For Weight Loss And Weight Maintenance In Women From Rural Communities: Results Of A Clinical Trial, Patricia A. Hageman, Carol H. Pullen, Melody Hertzog, Bunny J. Pozehl, Christine Eisenhauer, Linda S. Boeckner

Department of Nutrition and Health Sciences: Faculty Publications

Objective. This trial compared the effectiveness of a web-based only (WO) intervention with web-based supplemented by peer-led discussion (WD) or professional email counseling (WE) across 3 phases to achieve weight loss and weight maintenance in women from underserved rural communities.

Methods. 301 women (BMI of 28–45 kg/m²) randomly assigned to groups participated in guided weight loss (baseline to 6 months), guided weight loss and maintenance (6 to 18 months), and self-managed weight maintenance (18 to 30 months).

Results. Retention was 88.7%, 76.5%, and 71.8% at 6, 18, and 30 months, respectively. Intent-to-treat analyses demonstrated no group …

Prebiotics And Inflammatory Bowel Disease, Heather Rasmussen, Bruce R. Hamaker

Department of Nutrition and Health Sciences: Faculty Publications

Inflammatory bowel disease risk factors include poor diet, and corresponding low intake of dietary fiber, specifically prebiotics, which is fermented by the gut microbiota. Dietary fibers, many of which are potential prebiotics, have hundreds to thousands of unique chemical structures that may promote bacteria or bacterial groups to provide beneficial health effects. In vitro and in vivo animal models provide some support for the use of prebiotics for inflammatory bowel disease through inflammation reduction. Studies using prebiotics in patients with inflammatory bowel disease are limited and focus on only a select few prebiotic substances.

Keywords: Inflammatory bowel disease, Ulcerative colitis, …

Healthy Eating: How Do We Define It And Measure It? What’S The Evidence?, Christy C. Tangney, Beth A. Staffileno, Heather Rasmussen

Department of Nutrition and Health Sciences: Faculty Publications

A healthy diet can be defined in many ways, including defining one’s food intake by a dietary pattern. As described in the Dietary Guidelines for Americans Committee report, there are several defined dietary patterns associated with lower rates of chronic diseases. These include the Healthy Eating Index, Dietary Approach to Stop Hypertension, and those based on the Mediterranean diet. This review will focus on guiding health care professionals, including nurse practitioners, how a healthy diet pattern is defined, how it is measured, and a summary of recent evidence supporting the healthfulness of these dietary patterns.

Hepatocyte Abca1 Deletion Impairs Liver Insulin Signaling And Lipogenesis, Chia-Chi C. Key, Mingxia Liu, C. Lisa Kurtz, Soonkyu Chung, Elena Boudyguina, Timothy A. Dinh, Alexander Bashore, Peter E. Phelan, Barry I. Freedman, Timothy F. Osborne, Xuewei Zhu, Lijun Ma, Praveen Sethupathy, Sudha B. Biddinger, John S. Parks

Department of Nutrition and Health Sciences: Faculty Publications

Plasma membrane (PM) free cholesterol (FC) is emerging as an important modulator of signal transduction. Here, we show that hepatocyte-specific knockout (HSKO) of the cellular FC exporter, ATPbinding cassette transporter A1 (ABCA1), leads to decreased PM FC content and defective trafficking of lysosomal FC to the PM. Compared with controls, chow-fed HSKO mice had reduced hepatic (1) insulin- stimulated Akt phosphorylation, (2) activation of the lipogenic transcription factor Sterol Regulatory Element Binding Protein (SREBP)-1c, and (3) lipogenic gene expression. Consequently, Westerntype diet-fed HSKO mice were protected from steatosis. Surprisingly, HSKO mice had intact glucose metabolism; they showed normal gluconeogenic gene …

Calculating The Methan-Matics Of Our Future, Victoria Salinas

Op-Eds from ENSC230 Energy and the Environment: Economics and Policies

In the first two decades after its release, methane, a green house gas, is 84 times more potent than carbon dioxide. Historically, atmospheric concentrations of methane remained fairly stable at around 750 ppb, significantly less than today’s levels of 1,800 ppb. Unfortunately, agricultural activity accounts for about one-fifth of total global greenhouse gas emissions, while the current production of ruminants contributes nearly 80% of these emissions due to their large populations, body size and appetites, and the anaerobic microbial fermentation that occurs during digestion. Because of methane’s severe impact on the climate, methane emissions, specifically due to the production of …

Motility And Adhesion Through Type Iv Pili In Gram-Positive Bacteria, Kurt H. Piepenbrink, Eric J. Sundberg

Food for Health: Publications

Type IV pili are hair-like bacterial surface appendages that play a role in diverse processes such as cellular adhesion, colonization, twitching motility, biofilm formation, and horizontal gene transfer. These extracellular fibers are composed exclusively or primarily of many copies of one or more pilin proteins, tightly packed in a helix so that the highly hydrophobic amino-terminus of the pilin is buried in the pilus core. Type IV pili have been characterized extensively in Gram-negative bacteria, and recent advances in high-throughput genomic sequencing have revealed that they are also widespread in Gram-positive bacteria. Here, we review the current state of knowledge …

Investigating The Practices And Needs Of Agricultural Researchers At The University Of Nebraska-Lincoln, Leslie M. Delserone, Andrea L. Dinkelman

University of Nebraska-Lincoln Libraries: Faculty Publications

University of Nebraska-Lincoln (UNL) Libraries was one of 19 libraries participating in a national study, initiated by Ithaka S+R, of the research practices and needs of agricultural researchers. Two UNL Libraries faculty members participated in this study by interviewing 11 UNL agricultural scholars during the summer of 2016. The ethnographic research approach revealed four core themes explored in this UNL-specific report: interdisciplinarity and collaborations; scientific communication practices; scientific research data; and challenges and opportunities. Illustrated by the sample of faculty comments presented here, the themes have direct implications for the UNL Libraries, while in other cases these point to concerns …

Effects Of Feeding Field Peas On Fresh Beef Quality, Hope Voegele

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

The objective of this study was to evaluate the use of field peas during two phases of production (grazing and finishing) on fresh beef quality. A total of 232 crossbred steers and heifers were randomly assigned to one of six dietary treatments in a 3x2 factorial consisting of 3 pasture and 2 finishing supplementations. The pasture phase consisted of 1) no supplement, 2) field peas at 0.5% BW, or 3) dry-rolled corn supplement at 0.5% of BW. The finishing phase consisted of 1) field peas at 20% DM or 2) no field peas. During this two-year study, steers (year 1) …

Managing Corn Residue And Double Cropped Forages In Crop And Livestock Systems, Kristen M. Ulmer

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

Integrating crop and livestock systems leads to opportunities to utilize land resources; however, crop producers focus on grain yields and ground cover, while livestock producers see opportunity to graze corn residue or annual forages. After wheat harvest or corn silage harvest, above ground forage production for brassica mixes and oats is greater than forage oats or oat production after high moisture corn harvest. Grazing steers on forage crops after grain harvest provides moderate gains. While annual forages provide good quality forages, corn residue grazing and utilization is still a cost-effective feedstuff for cattle producers. In the short term, grain yields …

Effects Of Feed Additives And Body Weight On Growth Performance And Carcass Characteristics Of Beef Finishing Cattle, Curtis J. Bittner

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

A pooled-analysis of feedlot pens examined the effects of steer age (calf-fed, short yearling, long yearling) and initial body weight on feedlot growth performance. Feed efficiency decreased linearly as initial body weight increased for all age groups of steers.

Three feedlot experiments evaluated the effects of NEXT ENHANCE (EO) and monensin/tylosin (MT) on growth performance and carcass characteristics in beef finishing diets. In Exp. 1, there were no MT x EO interactions for finishing performance and carcass characteristics. Feeding MT resulted in a 3.9% improvement in G:F compared to steers fed no MT. Feed efficiency was not different between steers …

Effects Of Field Pea Usage In Growing And Finishing Diets For Beef Cattle, Hannah L. Greenwell

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

The value of field peas (FP) as a feedstuff has not been thoroughly assessed and compared to other feeds, such as corn, to better establish an economic value. Field peas are characterized by a high CP content (23-26%), a large portion (80%) being rumen degradable protein (RDP), and containing almost a third less starch (31-40%) than corn. Three research trials were performed to better understand the value of FP as a grazing supplement, finishing diet component, and any effects on digestion. Experiment 1 assessed the value of FP as a grazing supplement compared to corn. Grazing was followed by a …

The Influence Of Diet And Oxidation On Calcium Retention Of The Mitochondria In Fresh Beef, Emery K. Wilkerson

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

Distillers grains (DG) contribute to cattle sarcoplasmic reticulum (SR) membrane instability by increasing poly-unsaturated fatty acid (PUFA) content in the SR membrane, possibly resulting in early postmortem calcium (Ca) leakage and improved tenderness. Mitochondria are relatively easy to isolate intact and provide the opportunity to study Ca in an SR model. The objective of this research was to determine the influence of diet and oxidation on Ca release from mitochondria. Cattle (n = 48) were fed a corn-based finishing diet with or without deoiled, dried DG (50% DM basis). Steaks from each strip loin were aged for 2, 8, …

Reproductive Characteristics Of Landlocked Fall Chinook Salmon From Lake Oahe, South Dakota, Kelsen L. Young, Michael E. Barnes, Jeremy L. Kientz

The Prairie Naturalist

Lake Oahe, South Dakota, USA, landlocked fall Chinook salmon (Oncorhynchus tshawytscha) reproductive characteristics were examined over a 27 year period, from 1988 to 2015. Mean total lengths of spawning females ranged from 665 mm (1995) to 812 mm (2015) with considerable year-to-year variation. Post-spawn female weights varied, ranging from 2.02 kg (2000) to 5.55 kg (2015), with an overall mean of 3.04 kg. Fecundity peaked at 4,555 eggs per female in 2003, which was just 3 years after a low of 2,011 eggs per female in 2000. Relative fecundity based on female weight was greatest at 1,211 eggs/kg …

Multiplencc: Inverse Probability Weighting Of Nested Case-Control Data, Nathalie C. Støer, Sven Ove Samuelsen

The R Journal

Reuse of controls from nested case-control designs can increase efficiency in many situations, for instance with competing risks or in other multiple endpoints situations. The matching between cases and controls must be broken when controls are to be used for other endpoints. A weighted analysis can then be performed to take care of the biased sampling from the cohort. We present the R package multipleNCC for reuse of controls in nested case-control studies by inverse probability weighting of the partial likelihood. The package handles right-censored, left-truncated and additionally matched data, and varying numbers of sampled controls and the whole analysis …

Volumetry Of Low-Contrast Liver Lesions With Ct: Investigation Of Estimation Uncertainties In A Phantom Study, Qin Li, Yongguang Liang, Qiao Huang, Min Zong, Benjamin Berman, Marios A. Gavrielides, Lawrence H. Schwartz, Binsheng Zhao, Nicholas Petrick

United States Food and Drug Administration: Publications

Purpose: To evaluate the performance of lesion volumetry in hepatic CT as a function of various imaging acquisition parameters.

Methods: An anthropomorphic abdominal phantom with removable liver inserts was designed for this study. Two liver inserts, each containing 19 synthetic lesions with varying diameter (6–40 mm), shape, contrast (10–65 HU), and both homogenous and mixed-density were designed to have background and lesion CT values corresponding to arterial and portal-venous phase imaging, respectively. The two phantoms were scanned using two commercial CT scanners (GE 750 HD and Siemens Biograph mCT) across a set of imaging protocols (four slice thicknesses, …

Edible Insects As A Source Of Food Allergens, Lee Palmer

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

Increasing global population increasingly limited by resources has spurred interest in novel food sources. Insects may be an alternative food source in the near future, but consideration of insects as a food requires scrutiny due to risk of allergens. Currently, the insect Dactylopius coccus, known as cochineal, is used to produce carmine, a natural red pigment used in food, which has caused allergic reactions. This study investigated allergens of cochineal focusing on purification from the pigment. Mass spectrometry identified a previously described major allergen of cochineal and a tropomyosin, although further work is required.

Tropomyosin is a major cross-reactive allergen …

Risk Assessment And Research Synthesis Methodologies In Food Safety: Two Effective Tools To Provide Scientific Evidence Into The Decision Making Process, Juan E. Ortuzar

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

The food supply chain is a complex and diverse system. Some food products need minimum processing to reach the consumers, while others involve several different processes, countries and suppliers, can take several months to be on the table of the end consumer. Regarding food safety, the public health of consumers is at stake and the consequences of outbreaks could prove disastrous. This has been recognized as a matter of global importance for the food industry and authorities around the world since several efforts to improve quality, safety and trade of food have arisen since the early 1960s. The birth of …

Formation Of Bioactive-Carrier Hollow Solid Lipid Micro- And Nanoparticles, Junsi Yang

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

In recent years, bioactive lipids (e.g., carotenoids, phytosterols, and tocopherols) have attracted a lot of interest to develop health and wellness promoting foods and beverages. However, bioactive lipids are water-insoluble and degrade easily during processing and storage, making their addition into foods and beverages challenging.

The main objective of this thesis was to develop a novel green process to form bioactive lipid-carrier hollow solid lipid micro- and nanoparticles using supercritical carbon dioxide (SC-CO₂). Specific objectives were to develop hollow solid lipid micro- and nanoparticles using SC-CO₂ technology, and to load the hollow solid lipid micro- and nanoparticles …

Complex Vegetation Dynamics At The Fire–Grazing–Drought Nexus, Christine H. Bielski

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

The discipline of ecology long ago moved away from viewing systems as static entities where disturbance processes, environmental stochasticity, and spatiotemporal variability play minor roles in determining ecosystem structure and function. Ecological theory continue to develop frameworks and statistical techniques capable of describing the inherent complexity in natural systems. However, in dealing with the complexity in nature, many applied disciplines have yet to adopt such frameworks or statistical techniques. The objective of this study was bridge the gap between ecological theory and application by using complex systems theory to describe grassland vegetation dynamics at the fire-grazing-drought nexus. Chapters 2 and …

How Female Online Businesses And Brands Are Using Instagram Stories, Hannah N. Vanderslice

College of Journalism and Mass Communications: Theses

Instagram is one of the newest forms of social media that impacts its audience on a visual level, since the content is centered on photos and videos. Their newest feature, Instagram stories, is temporary videos and/or photos strung together to form a gallery, which has been compared to Snapchat’s version of live stories. Instagram stories offer a unique opportunity for businesses to take advantage of the temporary, 24-hour platform that shows specific frame-by-frame analytics that help create efficient and compelling content to repost permanently that helps organic search engine optimization. As a cost-effective means of advertising, early adopter large and …

Effect Of Smooth Bromegrass Management On Grazing Cattle Dung Decomposition, Co2 Flux, And Soil Nutrient Movement, Bradley D. Schick

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

Rapid nutrient cycling improves forage quality and livestock production in pastures. Interseeding legumes may be a strategy to enhance N cycling, but effects of dung excreted from cattle grazing pastures with legumes on dung decomposition rates and soil N cycling have not been studied. Our objective was to evaluate how dung excreted from cattle grazing legume-interseeded, N-fertilized, and unfertilized smooth bromegrass (Bromus inermis Leyss.) pastures affects dung chemical composition, dry matter decomposition, CO­₂ flux, and N availability in soil. Freshly deposited dung from yearling steers grazing legume-interseeded, N-fertilized, and unfertilized pastures was collected and placed as pats in …

Resistance Of Rice Varieties To Sitophilus Oryzae (Coleoptera: Curculionidae), Diana Cristina Da Silva Costa, André Cirilo De Sousa Almeida, Marcio Da Silva Araújo, Elvis Arden Heinrichs, Mabio Chrisley Lacerda, José Alexandre Freitas Barrigossi, Flávio Gonçalves De Jesus

Department of Entomology: Faculty Publications

Abstract

Rice, Oryza sativa L. (Poaceae), is one of the world’s most important food crops. Among the insects that damage rice grains, the rice weevil, Sitophilus oryzae (L.) (Coleoptera: Curculionidae), is the most important species. The objective of this study was to identify rice varieties with resistance to S. oryzae as measured by grain feeding damage and S. oryzae reproduction. The rice varieties evaluated were obtained from the germplasm bank of the National Center of Research Rice and Beans, Embrapa, Brazil. The experimental design was completely randomized with 3 replications and 22 treatments (varieties). The varieties Bonança, Esmeralda, and Rio …

Investigation Of Lipid Profile Patterns Along Latitude In An Eastern Australian Cline And After Stress Selection In The Laboratory, And Experiments On Stress Tolerance With Rnai Knockdown Of Lipid Biosynthesis Genes, Li Ko

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

Homeoviscous adaptation in membranes and changes in energy storage lipids such as triacylglycerols (TAGs) are the two main themes of adaptation to environmental conditions. Basal patterns of lipid compositional profile of Drosophila melanogaster along a latitudinal gradient in the eastern coast of Australia indicate variations of lipidome associated with climatic patterns. Lipidome data were collected for eight locations along the eastern Australian cline for both sexes in D. melanogaster and D. simulans. To further investigate the relationship between lipidome patterns and environmental factors, we utilized laboratory selection studies using stress conditions including high temperature tolerance, desiccation survival, and chill-coma …

Integration Of Plant Defense Traits With Biological Control Of Arthropod Pests: Challenges And Opportunities, Julie A. Peterson, Paul J. Ode, Camila Oliveira-Hofman, James D. Harwood

Department of Entomology: Faculty Publications

Crop plants exhibit a wide diversity of defensive traits and strategies to protect themselves from damage by herbivorous pests and disease. These defensive traits may be naturally occurring or artificially selected through crop breeding, including introduction via genetic engineering. While these traits can have obvious and direct impacts on herbivorous pests, many have profound effects on higher trophic levels, including the natural enemies of herbivores. Multi-trophic effects of host plant resistance have the potential to influence, both positively and negatively, biological control. Plant defense traits can influence both the numerical and functional responses of natural enemies; these interactions can be …

A Generalized Framework For Computational Design And Mutational Scanning Of T-Cell Receptor Binding Interfaces, Timothy P. Riley, Cory M. Ayres, Lance M. Hellman, Nishant K. Singh, Michael Cosiano, Jennifer M. Cimons, Michael J. Anderson, Kurt H. Piepenbrink, Brian G. Pierce, Zhiping Weng, Brian M. Baker

Food for Health: Publications

T-cell receptors (TCRs) have emerged as a new class of therapeutics, most prominently for cancer where they are the key components of new cellular therapies as well as soluble biologics. Many studies have generated high affinity TCRs in order to enhance sensitivity. Recent outcomes, however, have suggested that fine manipulation of TCR binding, with an emphasis on specificity may be more valuable than large affinity increments. Structure-guided design is ideally suited for this role, and here we studied the generality of structure-guided design as applied to TCRs. We found that a previous approach, which successfully optimized the binding of a …