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Using Pimephales Promelas>/Em> As An Indicator Species For The Presence Of Endocrine Disruptors In Nebraskan Streams, Megan Rosno

Department of Environmental Studies: Undergraduate Student Theses

Specific sites in Southeast and Southwest Nebraska were chosen to add to the collective knowledge on how cattle feed lot effluents continue to have significant effects downstream of their point source locations. Both locations were sampled via seining net in first: 40.241249 latitude, -95.616191 longitude (near Barada, Nebraska), and second: 41.117368 latitude, -100.794332 longitude (directly South of North Platte in the South Platte River). They were chosen not only for their proximity to differing livestock practices of pasture vs. feed lot, but also where locals fish for the best bait fish including but not limited to fathead minnows (Pimephales …

Changes In Plant Phenology In The Central United States In Response To Climate Change, Sarah Fagras

Department of Environmental Studies: Undergraduate Student Theses

Plant phenophases are highly sensitive to changes in temperature, precipitation, and photoperiod and have recently been identified as an indicator of climate change. Flowering time in particular appears to be sensitive to changes in temperature and plants around the world have already been observed flowering earlier than previously recorded. To determine how plants in the Midwest and Great Plains have reacted to climate change from the 1880s to present, 1,926 plant specimens made up of 10 species were examined to determine their phenophase and date of collection for each specimen was recorded. Analysis of these specimens shows that flowering time …

Age Structures And Growth Patterns Of Aplodinotus Grunniens In The Red River Of The North, Manitoba, Canada, Kaitlyn Elder

Department of Environmental Studies: Undergraduate Student Theses

A fishery and its components are an integral part of society and contribute not only economically, but also socially and physically to the health and well-being of many countries. There are approximately 12.5 million people who are employed in fishery-related careers, and according to the Wildlife and Sport Fish Restoration, there were over 33.1 million people who fished recreationally. To successfully manage a fish population, one must have a well-rounded knowledge about the species and the environment it inhabits. There is very little previous research done on the growth of Aplodinotus grunniens, otherwise known as freshwater drum (FWD), making it …

Activity Patterns Of Nebraskan Wildlife On A Prairie Landscape, Dillon Hanson

Department of Environmental Studies: Undergraduate Student Theses

Avoiding a particular species temporally can be an effective way to live amongst predator and competing species when spatial avoidance is not available. If a predator and prey species overlap temporally there is potential for high predation of the prey species by the predator, while if two predators overlap temporally there is high potential for competition and a loss of opportunities and resources for each species. I assessed if native mammalian species on a natural prairie landscape showed signs of avoidance through their activity patterns. I used photographic sampling to quantify the temporal activity patterns of species at Spring Creek …

The Impact Of Urbanization And Land-Use Change In Lincoln, Nebraska, Andrew Rose

Department of Environmental Studies: Undergraduate Student Theses

This study will take place in Lincoln Nebraska to investigate population density and urban encroachment onto agricultural lands. With urbanization on the rise we will inevitably face land use issues in the future. This research will investigate one strategy on how to build the city of Lincoln while using agriculture as a focal point. Keeping land sparing techniques in mind as we build will be an important component to saving enough land to grow food, shelter, and clothing for a growing population. One important question that will be looked at in this research is how urban expansion has consumed agricultural …

Nitrate Contamination And Nitrogen Isotope Compositions In The Bazile Groundwater Management Area: A Water Quality Study. Creighton, Ne, Sydney Corcoran

Department of Environmental Studies: Undergraduate Student Theses

Surface water nitrogen contamination is a pervasive issue in Nebraska, and agricultural practices are the main source of nitrogen input to streams (Spalding and Exner, 1993). Nitrate can come from inorganic fertilizers such as anhydrous ammonia, or animal waste. Studies have been conducted on nitrates dating back to 1947 (Addleman, 1985). The Bazile Groundwater Management Area (BGMA) located in northeast Nebraska has historically had high nitrate contamination. This qualitative study assesses the seasonal sources of nitrogen to stream water. It is predicted that the source of input is from commercial synthetic fertilizers. By using nitrogen- oxygen isotope methods, the source …

Use Of Annual Forage Mixtures In Crop/Livestock Production Systems In Nebraska, Nathan Paul Pflueger

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

Success of integrating annual forages into crop and livestock systems throughout Nebraska may be variable depending on field location, field/forage crop management, and precipitation. There are many different warm- and cool-season annual forage species available for integrating crop and livestock systems at different times of the year. Mixtures of cereal species, such as oats (Avena sativa)) and spring peas (Pisum sativum)), are often used to optimize forage quantity and forage quality. Our two-year, three location study across Nebraska’s precipitation gradient suggested that forage quantity and quality may vary by location due to different precipitation amounts received …

Effect Of Soil-Applied Protoporphyrinogen Oxidase Inhibitor Herbicides On Soybean Seedling Disease, Nicholas J. Arneson

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

Seedling disease is one the most economically important diseases of soybean in the United States. It is commonly caused by Fusarium spp., Rhizoctonia solani, Pythium spp., and Phytophthora sojae, alone, or together as a disease complex. Fungicide seed treatments continue to provide the most consistent management of seedling diseases. Soil-applied protoporphyrinogen oxidase (PPO) inhibitor herbicides are used preemergence in soybean production to manage several broadleaf weeds. Applications of PPO-inhibitors can result in phytotoxic injury to soybean when environmental conditions are not favorable for soybean growth. These environmental conditions can favor seedling disease development as well. In this thesis, two …

Perspectives Of Campus Safety: Viewpoints Of Community College Faculty And Staff Members, David E. Dibelka Jr.

Department of Educational Administration: Dissertations, Theses, and Student Research

There is research available on campus safety perspectives and issues, but these studies are primarily from the student perspective. Of the few studies that show campus safety perspectives from the faculty and staff viewpoint, fewer of these studies reflect these perspectives as they occur on community college campuses. The purpose of the study was to examine the perspectives of faculty and staff members on campus safety. For the study, twenty faculty and staff members were interviewed about their perceptions of campus safety.

The results of the study were that although the participants generally felt safe on their campuses, they were …

Generativity Development Of College Students Who Mentor, Nick Knopik

Department of Agricultural Leadership, Education, and Communication: Dissertations, Theses, and Student Research

Research has shown that college students who mentor demonstrate higher levels of generativity than other college student leaders and general college students; yet, it is unclear whether college student mentors develop generativity over time as a result of their mentoring experience or enter a mentoring relationship because their generativity is already well-developed. This study compared the levels of generativity within individuals and across age cohorts during a one-year time period while controlling for gender for college students who mentor. Three quantitative generativity measures were used to collect data from a sample of 45 college student mentors at two time points, …

Weight Status, Bullying Involvement, And Internalizing Symptomology In Adolescents: Examining A Diathesis-Stress Model, Ana Damme

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

Bullying is a pervasive societal issue that is consistently linked to negative outcomes that are emotionally, socially, behaviorally, and medically related. Most youth will encounter this negative life event in their childhood. The purpose of this dissertation was to use a diathesis-stress model perspective to assess the relations between the negative life event of bullying involvement, youths’ mental health, and youth weight status. Youth who have an unhealthy weight status are more likely to be involved in bullying than those with a healthy weight status (Browne, 2012; Puhl). Additionally, bullying and having an unhealthy weight status are related internalizing symptomology …

Effects Of Conjoint Behavioral Consultation On Student-Teacher Interactions, Sonya A. Bhatia

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

Young children with disruptive classroom behaviors are at-risk for negative interactions with their teachers (Nelson & Roberts, 2000), which put children at increased risk for long-term negative social, academic, and behavioral outcomes (Sutherland & Oswald, 2005). Conjoint Behavioral Consultation (CBC) is an evidence-based family-school partnership intervention focused on strengthening relationships and promoting continuity and consistency between children’s key environments (Sheridan & Kratochwill, 2008). The efficacy of CBC on child outcomes and parent-teacher relationships has been demonstrated (Sheridan et al., 2017); however, no research has determined whether CBC improves student-teacher interactions.

This study examined CBC’s effect on student-teacher interactions using a …

Using Self-Regulation To Predict Preschoolers' Symptomology Of Disruptive Behavior Disorders, Andrew White

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

The use of brief rating forms completed by caregivers to identify children at-risk for developing behavioral disorders is common (Lane et al., 2009). However, identifying a behavioral measure assessing child-level variables (i.e., temperamental traits) which predict later behavioral concerns has potential to improve universal screening practices in the context of a multi-tiered systems of support (MTSS) framework. Self-regulation (Rothbart & Bates, 2006) is a trait that is related to externalizing problem behaviors (e.g., Espy et al., 2011), and may be useful as a means to predict young children at risk for developing behavioral disorders. The purpose of this study is …

Addressing The Challenges Facing Wheat Production: Nebraska And International Breeding Efforts, Sarah Blecha

Doctor of Plant Health Program: Dissertations and Student Research

Bread wheat, Triticum aestivum L., provides 20 percent of the global daily calorie intake. It is the third most important food crop, after rice and corn. Biotic challenges significantly reduce wheat yield; chemical control can be a solution but can be cost prohibitive for subsistence farmers. For many farmers, genetic resistance to biotic stresses can be the most cost effective solution.

The International Center for Agricultural Research in the Dry Areas (ICARDA) and the Nebraska Small Grains Breeding Program have been addressing these wheat production challenges. ICARDA is part of an international research consortium to increase wheat yield and tolerance …

Science Communication In Agriculture: The Role Of The Trusted Adviser, Lee Galen Briese

Doctor of Plant Health Program: Dissertations and Student Research

Agronomy is not simply the selling of agricultural products to farmers, nor is it the process of solving singular production problems. Agronomy is defined as the integrated, holistic perspective of agriculture (ASA, 2019) and “agronomists are specialists in crop and soil sciences, as well as ecology” (ASA, 2019). While scientific investigation and discovery are essential to understanding systems function, the tangible benefits from our knowledge stems from the application to solve problems. Clear communication is vital to successfully help stakeholders understand the importance of the science and help scientists understand the challenges stakeholders face. However, to successfully put science into …

Non/Human: (Re)Seeing The “Animal” In Nineteenth-Century American Literature, Matthew Guzman

Department of English: Dissertations, Theses, and Student Research

Non/human: (Re)seeing the “Animal” in Nineteenth-Century American Literature uses canonical literary texts as specific anchor points for charting the unstable relations between human and nonhuman animals throughout the century. I argue that throughout the nineteenth century, there are distinct shifts in the way(s) humans think about, discuss, and represent nonhuman animals, and understanding these shifts can change the way we interpret the literature and the culture(s). Moreover, I supplement and integrate those literary anchors, when appropriate, with texts from contemporaneous science, law, art, and other primary and secondary source materials. For example, the first chapter, “Cooper’s Animal Movements: Across Land, …

Characterization And Evaluation Of The Probiotic Properties Of The Sporeforming Bacteria, Bacillus Coagulans Unique Is-2, Amy Garrison

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

Probiotics are live organisms, that when consumed in adequate amounts, confer a health benefit to the host. To achieve probiotic status, each potential strain’s functional properties and their safety to the consumer must be comprehensively evaluated. Probiotic effects have been observed to be strain specific, therefore each new strain of interest must be characterized according to their phenotypic and genetic characteristics. There is a list of characteristics that potential probiotic strains should have to be considered as a probiotic. Potential probiotic strains should be evaluated for their acid and bile salt resistance, antimicrobial activity and adherence and colonization to intestinal …

The Niobrara National Scenic River: Exploring Co-Management Through A Case Study Of The Niobrara Council, Melissa M. Mosier

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

In recent decades, government staff and local citizens have increasingly employed cooperative schemes of natural resource management, in lieu of more conventional, top-down approaches of addressing user conflicts as they relate to water resources. The focus of this project was on the Niobrara Council, a partnership of local, state, and federal representatives charged with cooperatively managing the reach of the Niobrara River that was federally designated under the Wild and Scenic Rivers Act in 1991. The project's purpose was to explore the cooperative framework of the Council, using the methodology outlined by Carlsson and Berkes (2005). This methodology involved investigating …

Population Dynamics Of The Freshwater Mussel Lampsilis Cardium Reintroduced In Nebraska, Lindsay M. Ohlman

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

The global decline of native freshwater mussels has accelerated conservation projects that preserve and restore populations, but the complex life histories among species challenges biologists in determining the most effective management strategies. This study details the conservation of plain pocketbook, a Tier I threatened mussel species in Nebraska that was artificially propagated and reintroduced into 13 sites from autumn 2016 to summer 2017. The objectives of this study were: 1) determine how handling influences mussels, and 2) evaluate mussel growth and survival following introductions.

We conducted a laboratory experiment with age-2 plain pocketbook to assess the effects of handling on …

Implementing The North American Bat Monitoring Program In Nebraska: An Assessment Of Nebraska Bats With An Emphasis On Citizen Science, Baxter Seguin

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

Over the past decade bat species in North America have been under immense stress due to anthropogenic activities throughout the continent along with severe declines from foreign invaders. Though many specific anthropogenic related activities such as deforestation, land-use alteration, and hibernacula disturbance/modification were the primary culprits of negative impacts on bat species in the past, they pale in comparison to the threats bats face today. White nose syndrome a disease caused by the fungus Pseudogymnoascus destructans and wind energy development have caused declines and disruptions to the bat populations of North America at an unprecedented rate.

Due to the significant …

A Data-Driven Approach For Detecting Stress In Plants Using Hyperspectral Imagery, Suraj Gampa

School of Computing: Dissertations, Theses, and Student Research

A phenotype is an observable characteristic of an individual and is a function of its genotype and its growth environment. Individuals with different genotypes are impacted differently by exposure to the same environment. Therefore, phenotypes are often used to understand morphological and physiological changes in plants as a function of genotype and biotic and abiotic stress conditions. Phenotypes that measure the level of stress can help mitigate the adverse impacts on the growth cycle of the plant. Image-based plant phenotyping has the potential for early stress detection by means of computing responsive phenotypes in a non-intrusive manner. A large number …

Social Networks And Science Identity: Does Peer Commitment Matter?, Grace Maridyth Kelly

Department of Sociology: Dissertations, Theses, and Student Research

White men continue to be overrepresented in STEM fields compared to women and minorities, despite several decades of scholarly interest the disparity. Studies have shown that early adolescence is when children begin to lose interest in science. It is also in this period, that children start to develop ideas and stereotypes about who should be a scientist. It is essential that youth are able to see themselves as science kinds of people. Students who have strong science identities have been shown to perform better in science classes, retain interest in science and continue on to STEM careers. During adolescence, peer …

Drinking Behaviors, Relationships And Recovery: A Relational Sociological Examination Of Addiction, Maia C. Behrendt

Department of Sociology: Dissertations, Theses, and Student Research

Examination of addiction from the theoretical framework of relational sociology contributes to growing efforts to understand and develop addiction recovery programs that focus on the restoration of important social relationships and ties. Aims of the study include understanding how alcohol addiction has been addressed in earlier sociological studies and to provide evidence for how relational sociology may be utilized to better understand and explain how alcoholics and Alcoholics Anonymous operate within Bateson’s Theory of Alcoholism and Addiction. Through a qualitative study and analysis of 20 in-depth audio recorded interviews with individuals in either active recovery or active drinking, this study …

Predictive Modeling Of Fate And Transport Of Three Prevalent Contaminants In Midwest Agroecosystem Surface Waters: Nitrate-N, Atrazine, And Escherichia Coli, Samuel Hansen

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

The majority of streams and rivers in the United States (U.S.) are ecologically impaired, or threatened by anthropogenic stressors. Recent reports have found atrazine in drinking water to be associated with increased birth defects and incidences of Non-Hodgkin’s Lymphoma, with higher levels of significance from exposure to both atrazine and nitrate-N. In contrast, recent illnesses from E. coli contaminating vegetables that originated from irrigation water has increased awareness of identifying sources of E. coli entering irrigation reservoirs.

Methods to accurately predict atrazine and E. coli occurrence and potential sources in waterways continue to limit the identifying appropriate and effective prevention …

Uumanned Aerial Vehicle Data Analysis For High-Throughput Plant Phenotyping, Jiating Li

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

The continuing population is placing unprecedented demands on worldwide crop yield production and quality. Improving genomic selection for breeding process is one essential aspect for solving this dilemma. Benefitted from the advances in high-throughput genotyping, researchers already gained better understanding of genetic traits. However, given the comparatively lower efficiency in current phenotyping technique, the significance of phenotypic traits has still not fully exploited in genomic selection. Therefore, improving HTPP efficiency has become an urgent task for researchers. As one of the platforms utilized for collecting HTPP data, unmanned aerial vehicle (UAV) allows high quality data to be collected within short …