Life Sciences Commons^™

Systematic Review: Effect Of Cover Crop On Working Farm, Noella A. Bahatsi

Honors Theses

On-farm research is when research techniques such as randomized, replicated treatments strips and large-scale techniques are used on actual farms or ranches. Due to a great deal of interest and curiosity among farmers and researchers who wish to make their farming methods more profitable, efficient, and/or sustainable, this type of research has been conducted more frequently each year. On-farm research has contributed to economic growth and the transfer of knowledge to farmers because of fresh discoveries and upgraded technology (Lacoste et al., 2022). This is also where farmers collaborate with researchers to test new management practices and technologies providing unbiased …

Economic And Input-Use Efficiency Of Nitrogen Management Techniques In Non-Irrigated Maize Production, Katie J. Bathke

Honors Theses

The efficiency of nitrogen (N) management has become a main concern in agricultural cropping systems for understanding the optimal N rate to help producers improve economically and reduce the exhaustion of natural resources environmentally. Nitrogen rates vary both temporally and spatially by the interactions of the soil environment and rainfall through a growing season. Thus, a site-specific approach can further optimize this variability with the understanding of the role soil variability plays in the N rate applied to a non-irrigated field. The objective of this study was to evaluate the various nitrogen treatments for their nutrient use efficiency and economic …

Utilizing Markov Chains To Estimate Allele Progression Through Generations, Ronit Gandhi

Honors Theses

All populations display patterns in allele frequencies over time. Some alleles cease to exist, while some grow to become the norm. These frequencies can shift or stay constant based on the conditions the population lives in. If in Hardy-Weinberg equilibrium, the allele frequencies stay constant. Most populations, however, have bias from environmental factors, sexual preferences, other organisms, etc. We propose a stochastic Markov chain model to study allele progression across generations. In such a model, the allele frequencies in the next generation depend only on the frequencies in the current one.

We use this model to track a recessive allele …

The Effects Of Covid-19 On Residential Municipal Waste Streams, Anne Kluthe

Honors Theses

Through interviews, this exploratory analytive study researched how COVID-19, and especially the first lockdown of 2020, changed residential municipal waste streams, specifically in terms of items, tonnage, and workplace practices. The most common items were an influx in PPE, specifically face masks, and an increase in cardboard. There was also some evidence of paper from “deep cleaning” projects and construction debris from backyard pool installation and bathroom renovation. The total change in waste varied from area to area. Norfolk and the surrounding area had a stagnant amount of waste during the pandemic, Omaha and the rest of Douglas County saw …

The Impact Of The Inclusion Of Grains In A Canine Diet On The Animal's Overall Health, Rachel Bruner

Honors Theses

The objective of this senior project was to examine the impacts that grains in a canine diet have on the overall health of the animal. Specifically, there was a focus on the nutritional attributes of grains, potential concerns regarding their inclusion in foods, misconceptions from consumers about grains in pet food, and alternatives to grains used in some diet formulations. The method of research for this project was a literature review. Scholarly articles focused on the various subtopics which helped to answer the research question were reviewed and included throughout the following discussion. Ultimately, the review of various literature resulted …

Investigation Of The Role Of Overexpression Of Psbs Under Stress Inducible And Constitutive Promoters To Improve Water Use Efficiency., Annie Nelson

Honors Theses

As climate change continues to impact environmental growth conditions, it has become increasingly more important to identify potential mechanisms of crop development to resist these changes. Previous studies have identified the role of PsbS in the non-photochemical quenching (NPQ) mechanism in the plant by identifying its direct effect on the rate in which excitation energy absorbed by photosystem II is dissipated as heat. It was identified also that PsbS via NPQ oxidizes chloroplastic quinone A (QA) which is a signal for stomatal opening in response to light. By identifying this relationship between PsbS and the signal for stomatal opening in …

A Cookbook For The Trendy Chef, Katja Roberts

Honors Theses

A Cookbook for the Trendy Chef contains a compilation of recipes which fall under 8 major food trends for 2021. These trends were determined to be vegan, keto, and gluten-free diets, along with “viral foods”, easy recipes, functional foods, international flavors, and comfort foods. These trends were selected based on predictions made by the Institute of Food Technologists (IFT) and the Washington Post.

Sex Differences In Lateral Hypothalamic Extracellular Glucose Concentrations During Cumulative Dosing Of Methamphetamine In Rats, Joshua A. Jolton

Honors Theses

The present study experimentally investigated sex differences in lateral hypothalamic glucose concentrations following cumulative dosing of methamphetamine. Male (n=17) and female (n=11) rats were surgically implanted with enzyme-based glucose biosensors in the lateral hypothalamus. Rats then received a saline injection followed by four methamphetamine doses (0.025 mg/kg, 0.05 mg/kg, 0.1 mg/kg, and 0.2 mg/kg) spaced 55 minutes apart. We found that while there was a general decrease in glucose baseline throughout the study for both sexes, the magnitude of the decrease was significantly greater in females compared to males. On a rapid timescale, fixed sex effects existed at the lower …

Ain't No Sunshine When They're Gone: Pollinators In A Solar Prarie, Brigid M. Morgan

Honors Theses

Around the world, pollinator populations are decreasing due to climate change, habitat loss and fragmentation, invasive species, pesticide use, and disease. A solar prairie can provide that habitat space with native plants to attract and promote the growth of native pollinator populations. In this study at the University of Dayton in Dayton, Ohio, I sought to find out if native pollinators were using the habitats inside and around the solar panels at Curran Place. By using pan traps weekly throughout the summer months to collect the insects, I found that native pollinators are using the habitats between the rows of …

A Starling In A Pear Tree: Assessing The Influence Of Bird Dispersal On Callery Pear (Pyrus Calleryana), Olivia Clark

Honors Theses

Invasive species can disrupt ecosystems and negatively affect other species. Callery pear (Pyrus calleryana) is an invasive ornamental tree that is spreading quickly throughout the United States. It is possible that birds are responsible for spreading Callery pear by eating the fruit and depositing seeds in new areas. European starlings (Sturnus vulgaris) and American robins (Turdus migratorius) are mentioned in most studies as responsible for the dispersal of Callery pear. However, there is also evidence that Cedar waxwings (Bombycilla cedrorum) also feed on the tree. Invasive plants can impact avian health, reproduction, and migration. Additionally, there are many aspects of …

The Impact Of Anaerobic Exposure And Propionate On The Kinetics And Pathogenesis Of Listeria Monocytogenes, Mackenzie T. Martin

Honors Theses

Listeria monocytogenes is a foodborne pathogen commonly found in ready-to-eat deli and dairy products. This foodborne pathogen is responsible for the disease listeriosis, which disproportionately impacts immunocompromised individuals. This research aims to evaluate how natural intestinal environments influence the pathogenesis of Listeria. One particular environmental condition that has a well-documented effect on Listeria is varying levels of oxygen. Specifically, anaerobic exposure during the growth of Listeria greatly impacts subsequent intracellular pathogenesis. When grown and adapted under anaerobic conditions, Listeria overall exhibits decreased intracellular survival and decreased cell to cell spread. However, the presence of propionate, a natural byproduct of fermentation …

Establishing A Drosophila Colon Cancer Model To Study Interactions And Therapeutic Targets Of Oncogenic Pathways, Kathleen T. Mccaslin

Honors Theses

The objective of this project is to develop an in vivo colorectal cancer (CRC) model in Drosophila melanogaster to test the role of Ras and Wnt pathways in gastrointestinal cancer as potential therapeutic targets. To do so, we have (a) developed a CRC model in flies, (b) tested the levels of Ras and Wnt pathway activity in this model, and (c) will use drugs to find inhibitors of these pathways. Using fly mutants and transgenic flies we have created small patches of cancerous cells in the fly intestine in which have activated oncogenic Ras (mutation RasV12) and dominant negative p53 …

Seabem: An Artificial Intelligence Powered Web Application To Predict Cover Crop Biomass, Aime Christian Tuyishime, Andrea Basche

Honors Theses

SEABEM, the Stacked Ensemble Algorithms Biomass Estimator Model, is a web application with a stacked ensemble of Machine Learning (ML) algorithms running on the backend to predict cover crop biomass for locations in Sub-Saharan. The SEABEM model was developed using a previously developed database of crop growth and yield that included site characteristics such as latitude, longitude, soil texture (sand, silt, and clay percentages), temperature, and precipitation. The goal of SEABEM is to provide global farmers, mainly small-scale African farmers, the knowledge they need before practicing and benefiting from cover crops while avoiding the expensive and time-consuming operations that come …

Source Of Off-Type Frequencies In Winter Wheat Varieties, Michaela Benes

Honors Theses

The enzyme polyphenol oxidase (PPO) is undesirable in most wheat products due to the discoloration it causes. Purifying wheat varieties through selective breeding is the best way at getting rid of PPO in a variety. The variety NW15443 was planted in both a field in McCook, NE, and in a greenhouse in Lincoln, NE. Individual heads were snapped from the field and the greenhouse seed was harvested in bulk. After completing a PPO test of the seed, it was determined that the percentages of off-type frequencies from the field seed and the greenhouse seed were 11% and 3.6%, respectively. Using …

Tiny Earth, Tinier Microbes: An Experiential Learning Approach To Antibiotic Discovery, Emily Kassing

Honors Theses

Antimicrobial resistance is one of the greatest global health challenges of the 21^st century as antibiotic discovery has slowed even as scientific knowledge about AMR has progressed. At the same time, science education has turned to active learning approaches like CUREs, or course-based undergraduate research experiences, to achieve educational objectives while engaging students in real-life research. The Tiny Earth Project is a global research initiative that seeks to crowdsource antibiotic discovery by recruiting undergraduate students to screen soil samples for antibiotic producers. The goal of this study was to determine the viability of translating the Tiny Earth programming to …

The Design Of An Agricultural Youth-Centered Rural Development Program In Rwanda, Laetitia Igiraneza Sinyigenga

Honors Theses

Rwanda is primarily a rural, young, and agriculture-based country. The referred variables- agriculture, rural population, and youth- can be creatively merged to engage and empower youth for rural development. This paper indicates the utilization of cross-disciplinary knowledge to design an agricultural youth-centered rural development program in Rwanda. The program uses the interdependence of economic sectors (agriculture and education) with resources (environmental & natural resources and human resources) to boost rural community development. The program’s main activities- mentorship, agribusiness training, tutoring, exposure visits, and community work- highly reflect the requirement for advancing the selected main economic sectors and resources. There is …

Comparison Of Transcervical Insemination Versus Surgical Insemination Methods In Dogs At A Veterinary Clinic In Lincoln, Nebraska, Lauren Ahlers

Honors Theses

Artificial insemination paved the way for many advancements in reproductive technology. Two common artificial insemination methods recommended for use with frozen semen are transcervical insemination and surgical insemination. To better understand the conception rates of dogs for each method, data was collected from Hillcrest Animal Clinic. The data suggested that neither transcervical insemination nor surgical insemination was significantly better than the other. 50% of the dogs conceived when inseminated using the transcervical method, and 54.5% of the dogs conceived when inseminated using the surgical method. Based on the results, more data needs to be collected on both insemination procedures to …

Determining Pairwise Interactions To Predict Species Interactions In A Complex Community Of Gut Bacteria., Makenzie Maroney

Honors Theses

The human gastrointestinal (GI) tract houses a diverse and expansive microbial community known as the microbiota. The relationship between the host and the microbiota is considered to be mutualistic, as trillions of bacteria that reside in the hospitable GI tract can assist in essential host functions, including contributing to metabolism and immunity against disease. An important subpopulation of the GI microbiota is the mucin-associated biofilm that is comprised of a dense layer of bacteria that forms on the GI mucin layer. The mucin layer provides an alternative niche to the GI lumen; the glycans of the mucin and the subsequent …

Developing Activities On Uncharismatic Animals Found At Omaha's Henry Doorly Zoo And Aquarium, Justin Hultquist

Honors Theses

The Education Department at Omaha’s Henry Doorly Zoo and Aquarium has a number of educational activities based on charismatic species found there. I wished to develop activities the department may use for less charismatic or misunderstood species at the zoo. I began by surveying the exhibits at the zoo and taking note of what species or groups didn’t receive as much visitor engagement, or what comments were made on species that were incorrect. I then began to brainstorm and narrow down potential species that I could develop an educational activity around. As I began to develop and create activities, a …

Influence Of Fertilizer Rate On Swollen Stem Formation (“Bulbing”) And Vitamin C Content In Different Kohlrabi Cultivars, Mark Iradukunda, Paul E. Read

Honors Theses

Kohlrabi (Brassica oleracea Gongylodes Group) is a vegetable crop found in the Brassicaceae, and it is rich in antioxidants such as vitamin C. Vitamin C helps in oxidative damage repair and strengthens the immune system, so exploring vitamin C sources may contribute to improving human health. The objective of this study was to determine the effect of different fertilizer rates on kohlrabi yield, in terms of the swollen stem and the vitamin C content, and if those effects are similar in different kohlrabi cultivars. In this greenhouse study, we fertilized four potted kohlrabi cultivars with a common water-soluble greenhouse fertilizer …

Bacteriophage That Infect Gordonia Species Show Varying Host Specificity And Infection, Lindsay Birge

Honors Theses

Bacteriophage (phage) are an incredibly abundant species of virus that infect bacteria. One major characteristic of phage is their small host range- many phage are known to infect only one or a few hosts. This phage and host relationship has led to phage therapy recently becoming highlighted as a possible alternative to traditional antibiotics in light of the growing antibiotic resistance crisis. The study of phage host specificity has risen in line with this concept, as a phage with a more extensive host range can provide more opportunities for use as an antibiotic. Samples of phage previously isolated on a …

The Crucial Role Of Sestrins In Oxidative Stress Response And Disease: An Analysis Of Phosphorylation Mutation S110a In Hsesn2, Julianne Fay

Honors Theses

Sestrins are highly conserved proteins which are induced under environmentally stressful conditions to adjust the cell’s response to such disturbances. This protein possesses two domains critical for its dual function in reducing reactive oxygen species (ROS) and regulating the mTORC1 complex. Sestrins may use diverse transcription factors, such as Nrf2, peroxiredoxin reductase activity, and a catalytic cysteine to regenerate oxidized species; however this was confirmed to be through a mechanism likely different than AhpD, for which there was distance sequence similarity. Furthermore, Sestrins are important regulators of TORC1 and AMPK, which are crucial energy sensors able to control cellular metabolism …

Supplemental Peer Instruction In Physiologic Core Concept Education, Austin Choat

Honors Theses

The objective of my thesis project was to create and research the importance of supplemental learning videos within core physiological concepts identified by the Advancement of Physiological Principles for the purpose of assisting Dr. Kim Hansen in better educating students with less extensive foundational knowledge of chemical and biological sciences. Through researching the benefits of peer instruction, identifying core physiological concepts crucial to wholistic physiology education, and describing a student population hypothesized to benefit substantially from the work, I created educational videos to aid Dr. Hansen in her work as an educator and in the educational research she is striving …

Optimization And Standardization Of Dms Chemical Mapping Experiments For Probing Rna 3d Structure, Sarah Brady

Honors Theses

RNA plays a significant and crucial role in biological processes. The properties of RNA are ultimately responsible for each molecule’s unique function. The configuration and structural integrity of RNA is important for its functionality. Chemical mapping detailed in this thesis can be used to analyze the 3D structure of an RNA sequence. RNA is modified via methylation of adenine and cytosine bases using dimethyl sulfate, then reverse transcribed to DNA, then sequenced. The sites where the bases were methylated become mutations in the DNA sequence, allowing for identification of these locations when analyzing sequencing data. Conditions for modification can be …

Genomic Analysis Of Acetoanaerobium Sp. Vlb-1, An Anaerobic Bacterium Isolated From Nebraska's Eastern Saline Wetlands, Claire Martin

Honors Theses

Through the analysis of genetic code, the genomic and physiological characteristics of an environmental anaerobic bacterial isolate, Acetoanaerobium sp. strain VLB-1, can be determined and significant pathways can be identified in its significance to the environment. This particular organism was isolated from the Eastern Saline Wetlands in Lincoln, NE. With this isolate, an investigation into elemental and amino acid cycling via the Stickland reaction and the Wood-Ljungdahl pathway was conducted to determine possible metabolic products. The Stickland reaction is a relatively newly discovered pathway, observed in the genus Clostridium. A. sticklandii is the main model for this method of …

Can Gdp Be Predictive Of Fertility Rates In Sweden?, Hannah Coleman

Honors Theses

Fertility rates in a country vary and can be influenced by numerous different aspects of an individual’s life and the society in which they live. One aspect that may influence fertility rates at the national level is the gross domestic product (GDP). GDP is an indicator of a country’s economic productivity. Because fertility is linked to both economic development and individual resources, GDP may be a useful indicator of fertility rates. If so, knowing or predicting GDP could be used to project the fertility rates of a population years into the future. To determine if a reasonable connection between GDP …

Biochar: Properties And Potential Benefits For Agricultural Soil In Rwanda, Andromede Uwase

Honors Theses

Physical and chemical soil degradation is becoming a major challenge for agricultural productivity in Rwanda, which is the most important part of the country’s economy. The wide spreading soil degradation in Rwanda is mainly a result of naturally poor soils coupled with unsustainable soil management leading to, for example, accelerated soil erosion, acidification, nutrient loss, compaction, and to decreasing yields. Biochar, as an end product of pyrolysis of biomass in the absence of oxygen, has been proposed as a soil amendment in remediation strategies because of its positive effects on soil productivity relevant parameters such as soil pH, structure, nutrient …

Targeting Transgenic Proteins To The Mitochondria In Plants, Susan Qudus, Jeffrey P. Mower

Honors Theses

Cytoplasmic male sterility (CMS) in plants can convert an individual into female through sterilization of the male reproductive parts, creating an inability to produce functional pollen. In nature, this is advantageous for genetic diversity and producing progeny with unique genes that may be beneficial in evolution. For agriculture, this method is preferential for selection of desirable traits in crops when cross breeding. CMS is typically caused by genes in the mitochondrial DNA (mtDNA), such as novel open reading frames (ORFs) that form after imperfect repair of double-stranded breaks in the mtDNA. Specific CMS genes vary among various plant species. It …

Hiv-1 Transcription Elongation By Tat-Mediated Recruitment Of P-Tefb, Elizabeth Griggs

Honors Theses

Over 38.0 million people live with the human immunodeficiency virus (HIV) as of 462019. HIV hijacks the host's cellular machinery to replicate its viral DNA and transcribe the corresponding RNA. HIV-1 transcription relies on both cellular and viral transcription factors for proper regulation. The viral transcriptional activator Tat is a primary regulator. Transcription activation and elongation is controlled through the interaction of Tat with Positive Transcription Elongation Factor b (P-TEFb), a cellular transcriptional activator. The focus of this paper is 1) an in-depth understanding of the interaction between P-TEFb and Tat in HIV transcription, and 2) a review of recent …

Analysis Of Single-Site Cysteine Mutation, I412c, In Human A Glycine Receptor States To Further Refine Structure And Allostery, Leah Engquist

Honors Theses

The glycine receptor (GlyR) is the major inhibitory receptor in the brain and spinal cord. A member of the pentameric ligand gated ion channel superfamily, crystal structures are available but there are still unresolved areas, specifically the C-terminal tail and TM3-TM4 intracellular loop. Further refinement can provide deeper understanding of the molecular mechanism and allow the creation of novel therapeutics to modulate its function. We propose to insert a single cysteine mutation, I412C, into a Cys null background (C41S/C290A/C345S) to study non- conducting states (resting, desensitized) or with F207G/A288G mutations to study the open state. Purified, reconstituted GlyR is crosslinked …