Digital Commons Network^™

Predator Defense And Host Selection Behavior Of Billbugs (Coleoptera: Dryophthoridae), Desireè M. Wickwar

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Billbugs are a complex of weevils that feed on the roots of turfgrass, causing severe damage to the plants. These pests are traditionally managed with applications of insecticides. However, there is a need for non-chemical management tools. Here I investigate billbug behavior in relation to two potential avenues for more sustainable management: using resident predators to suppress billbugs (Chapter II) and selecting specific turfgrasses that resist billbug damage (Chapter III). In Chapter II, I investigate the effects of predator presence and cues associated with their presence on billbug behavior. Though resident predators contribute very little to billbug suppression through directly …

Seeding Rate, Nitrogen Fertilzer, And Cutting Timing Effects On Teff Forage Yield And Nutritive Value, Michael C. Laca

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Teff [Eragostis tef (Zucc.) Trotter] is a relatively new forage gaining popularity in the United States; however, information regarding agronomic production practices is lacking. This study was conducted to determine the combination of seeding rate, fertilization, and harvest timing to optimize teff dry-matter yield (DMY) and nutritive value. Four seeding rates (2, 5, 8, and 11 lb/acre), four nitrogen (N) fertilizer rates (0, 25, 50, and 100 lb/acre), and two harvest strategies [boot stage (2-cut) and full seed-head stage (1-cut; stockpiled)] were evaluated in 2010 and 2011 in Kaysville, UT and Yerington, NV. The effects of harvest (1- vs …

Phytochrome Physiology And Plant Perception Of Far-Red Photons, Paul Kusuma

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Photons are the primary energy source for most life on Earth, as they drive photosynthesis, a process that turns the CO₂ in air into food. One crucial parameters for the optimization of growth is leaf area, which determines the ability of a plant to capture photons for photosynthesis. In order to gain access to photons in shaded environments, plants have evolved unique sensors, called photoreceptors, which respond to changes in the color and intensity of light.

Far-red photons (photons at the edge of human vision that appear as dim red light) hold particular promise in regulating plant shape and …

Characterization And Immobilization Of Thermophilic Lipases For The Interesterification Of Soybean Oil, Teif A. Najm

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Lipases are currently used in food technology for the modification of fats and oils. Lipase can synthesize, hydrolyze, and rearrange fatty acids, thus, resulting in their extensive use in industrial applications. The thermal stability of lipase is an essential characteristic for this application. Thermophilic bacteria are an important source for producing thermostable lipases because of their tolerance to high heat. Lipolytic enzymes can be purified using several purification methods, but these purification processes are often expensive and complex. Results from this study showed that lipases can be extract from thermophilic bacteria (Geobacillius stearothermophilus (GS) and Anoxybacillus flavithermus (AF)). Molecular …

Extended Maternal And Paternal Hereditary Risk For Alzheimer’S Disease Examined By Sex In A Sample Of Community Dwelling Older Adults In Cache County, Utah, Elizabeth K. Vernon

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

More than 6 million Americans are living with Alzheimer’s Disease (AD) and this number is expected to rise and surpass 12.7million individuals by the year 2050. Currently there is no cure for the disease and prior research has focused on prevention by identifying risk factors. Known risk factors associated with AD include older age, female sex, genetics, family history of AD, genotype of the apolipoprotein E (APOE) gene, and vascular risk factors (e.g., cholesterol, hypertension) and conditions or events (e.g., CHF, stroke). The effects of many of the above risk factors have differed in men and women, but few studies …

Determination Of The Structure, Function, And Mechanism Of Type Iv Crispr-Cas Prokaryotic Defense Systems, Hannah Nicole Taylor

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Bacteria are under constant threat of invasion by bacteriophage (viruses which infect bacteria). To prevent bacteriophage from entering and overtaking the bacteria, bacteria utilize defense systems to identify and destroy foreign elements. One method of defense is called CRISPR-Cas (Clustered Regularly Interspaced Short Palindromic Repeats – CRISPR-Associated). Many different bacteria and most archaea use CRISPR-Cas systems. There are many diverse types of CRISPR-Cas systems, each of which provides defense in a slightly different way. One such CRISPR-Cas type is called type IV. The type IV CRISPR-Cas system is poorly understood and there are very few studies published on type IV …

A Program Evaluation Of Competency Training Within A College Student Health Center, Kala E. Randazzo

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Integrated primary care (IPC) is a method for providing medical and psychotherapy services within a single primary care setting. Doctoral psychology students pursuing a career in psychotherapy may receive training in IPC as doctoral students. However, the field of IPC has a limited understanding of the current quality of IPC training for doctoral psychology students. The current study utilized professional competency guidelines for practicing psychology in IPC settings to evaluate doctoral training provided at the Utah State University Student Health Center. Doctoral psychology training at the Student Health Center was evaluated for how well it provides training in IPC competencies …

Comparison Of Microbial Diversity Of Fifteen Aged Cheddar Cheeses From Different Regions Using Next Generation Sequencing, Sophie L. Overbeck

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This project was funded by BUILD Dairy to test the efficacy of using next generation sequencing to study Cheddar cheese microbiomes. The 15 different cheese samples used in this study were purchased in the retail market from various manufacturers and different origins of manufacture. Sequencing was done by the Center for Integrated Biosystems at Utah State University using Illumina MiSeq.

The aim of this project is to provide further understanding of how using next generation sequencing can benefit the study of bacterial communities and their influence during the aging process of Cheddar cheese and the possibility of identifying defect causing …

Transplanting Mature Mountain Big Sagebrush Plants Yields High First-Year Survival In Dryland Pasture Restoration, Elizabeth C. Bailey

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Approximately 10-20% of global dryland ecosystems are severely degraded, an amount that is expected to increase, threatening the environment and ecosystem services that 38% of the global population relies upon. Human activities such as agriculture, livestock grazing, mining and urban development have contributed to the degradation and loss of rangelands worldwide. A need for reestablishing sagebrush in disturbed landscapes across the Western United States, including dryland pastures, has been identified but traditional, primarily seeding-based, restoration methods have largely been unsuccessful. To improve restoration outcomes, there has been increased interest in the planting of containerized greenhouse “tubelings”, but transplanting of mature …

Deep Learning Data And Indexes In A Database, Vishal Sharma

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A database is used to store and retrieve data, which is a critical component for any software application. Databases requires configuration for efficiency, however, there are tens of configuration parameters. It is a challenging task to manually configure a database. Furthermore, a database must be reconfigured on a regular basis to keep up with newer data and workload. The goal of this thesis is to use the query workload history to autonomously configure the database and improve its performance. We achieve proposed work in four stages: (i) we develop an index recommender using deep reinforcement learning for a standalone database. …

Social Media Usage And Psychological Well-Being In Adolescents: A Comparison Among Demographics, Heather A. Mccall

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The purpose of this study was to examine social media use of adolescents in the U.S. and their psychological well-being to expand the research of this quickly changing topic. The researcher collected online responses from 409 adolescents between the ages of 13-17 years old concerning their social media use and psychological well-being.

Variables in the research included time spent on social media, number of platforms used, active use, parental mediation, and emotional connection. The two variables that had a statistically significant relationship with psychological well-being included parental mediation and emotional connection to social media.

Recommendations for continued research could include …

Spatial And Long-Term Temporal Changes In Water Quality Dynamics Of The Tonle Sap Ecosystem, Savoeurn Soum, Peng Bun Ngor, Thomas E. Dilts, Sapana Lohani, Suzanne Kelson, Sarah E. Null, Flavia Tramboni, Zeb S. Hogan, Bunyeth Chan, Sudeep Chandra

Watershed Sciences Faculty Publications

Tonle Sap lake-river floodplain ecosystem (TSE) is one of the world’s most productive freshwater systems. Changes in hydrology, climate, population density, and land use influence water quality in this system. We investigated long term water quality dynamics (22 years) in space and time and identified potential changes in nutrient limitation based on nutrient ratios of inorganic nitrogen and phosphorus. Water quality was assessed at five sites highlighting the dynamics in wet and dry seasons. Predictors of water quality included watershed land use, climate, population, and water level. Most water quality parameters varied across TSE, except pH and nitrate that remained …

Photons From Nir Leds Can Delay Flowering In Short-Day Soybean And Cannabis: Implications For Phytochrome Activity, Paul Kusuma, F. Mitchell Westmoreland, Shuyang Zhen, Bruce Bugbee

Plants, Soils and Climate Student Research

Photons during the dark period delay flowering in short-day plants (SDP). Red photons applied at night convert phytochromes to the active far-red absorbing form (P_fr), leading to inhibition of flowering. Far-red photons (greater than 700 nm) re-induce flowering when applied after a pulse of red photons during the dark period. However, far-red photons at sufficiently high intensity and duration delay flowering in sensitive species. Mechanistically, this response occurs because phytochrome-red (P_r) absorbance is not zero beyond 700 nm. We applied nighttime photons from near infrared (NIR) LEDs (peak 850 nm) over a 12 h dark period. …

Fire Blight In Utah: An Annual Management Guide, Marion Murray

All Current Publications

Fire blight is a serious disease of apple and pear trees. Because this disease spreads rapidly and symptoms are not visible until two weeks after infection, it can catch growers off-guard. Having a well-executed and integrated year-round management program can reduce losses from fire blight.

A Novel Method For Detecting Wild Boar Presence, Giovanna Massei, Dave P. Cowan, Julia Coats

Human–Wildlife Interactions

Populations of wild boar and feral pigs (Sus scrofa) are increasing in numbers and distribution worldwide, in parallel with their significant environmental and economic impact. Reliable methods to detect the presence of this species are needed for monitoring its natural range expansion and its occurrence in areas where animals have been deliberately or accidentally introduced. The main aim of this study, carried out in English woodlands recently colonized by wild boar, was to assess the effectiveness of a birch wood tar-based compound, to detect the presence of this species in presence/absence surveys. A pilot trial in woodlands where …

Reduced Fecundity In Free-Ranging Norway Rats After Baiting With A Liquid Fertility Control Bait, Gary W. Witmer, Stefanie Raymond-Whish

Human–Wildlife Interactions

Norway rats (Rattus norvegicus) cause extensive crop loss, infrastructure damage, and are vectors for zoonotic diseases. Due to reduced efficacy, environmental and animal welfare concerns related to traditional pest management tools, such as rodenticides, it is imperative to find new methods for controlling commensal rodents. Fertility control is emerging as a safe, humane, and effective method of long-term population management. Vinylcyclohexene diepoxide (VCD) and triptolide are 2 compounds that are known to target and inhibit ovarian function. Furthermore, triptolide debilitates spermatogenesis and sperm motility. We prepared liquid bait containing no active ingredients (control) or containing VCD (0.098%) and …

Intensive Hunting Pressure Changes Local Distribution Of Wild Boar, Jakub Drimaj, Jiří Kamler, Radim Plhal, Přemysl Janata, Zdeněk Adamec, Miloslav Homolka

Human–Wildlife Interactions

Wild boar (Sus scrofa) is now an important species of wild ungulates in Central Europe. Next to conflicts of wild boar with agriculture, the main threat of wild boar presence lies in the expansion of African swine fever across Europe. The regulation of the wild boar population is complicated by the high reproduction rate and intelligent behavior of the species, which limits hunting effectiveness. We analyzed the spatial behavior of wild boar in an environment with a lack of natural food resources. The study area consisted of a forest complex (1,283 ha) with 2 areas. In the “risk” …

Evaluation Of Damage To Forest Tree Plantations By Wild Boar In The Czech Republic, Vlastimil Skoták, Jakub Drimaj, Jiří Kamler

Human–Wildlife Interactions

Wild boar (Sus scrofa) populations in Central Europe have been growing long-term, and damages to crops and forests where boars damage freshly planted tree seedlings are growing too. In addition to having a significant economic impact, these damages worsen the prospect of successful restoration of bare land. This study presents an analysis of damage to tree seedling plantations caused by wild boar in the Czech Republic. We used data from an extensive questionnaire survey among forest owners, our own survey of the extent of damage in model areas, and experiments in locations with a large boar population. Damage …

Utility Of Visual Counts For Determining Efficacy Of Management Tools For California Ground Squirrels, Roger A. Baldwin, Theresa A. Becchetti, Niamh Quinn, Ryan Meinerz

Human–Wildlife Interactions

Visual counts are frequently used to assess efficacy of management tools for ground squirrels (Marmotini), but the effectiveness of this approach has not been assessed for many ground squirrel species including California ground squirrels (Otospermophilus spp.). As such, we used visual counts of California ground squirrels to determine the efficacy of diphacinone-treated oat groat applications in rangelands in central California, USA, and compared those results to efficacy values derived from the use of radio-collared ground squirrels in the same plots. We also used location data of radio-collared ground squirrels to explore the size of buffer zone needed around census …

Characteristics Of Non-Fatal Attacks By Black Bears: Conterminous United States, 2000–2017, Janel M. Scharhag, Cady Sartini, Shawn M. Crimmins, Scott E. Hygnstrom, Jeffrey B. Stetz

Human–Wildlife Interactions

Attacks on humans by bears (Ursus spp.) have increased in recent decades, as both human and bear populations have increased. To help mitigate the risk of future attacks, it is important to understand the circumstances in past attacks. Information and analyses exist regarding fatal attacks by both American black bears (Ursus americanus) and brown bears (U. arctos) as well as non-fatal attacks by brown bears. No similarly thorough analyses on non-fatal attacks by black bears are available. Our study addressed this information gap by analyzing all (n = 210) agency-confirmed, non-fatal attacks by black …

Book Review: The Wildlife Techniques Manual, Eighth Edition, Justin Small

Human–Wildlife Interactions

Wildlife researchers and managers are consistently tackling ecological and conservation issues that are increasing in complexity and scope. Wildlife issues often span beyond singular research frameworks and management jurisdictions, preventing modern wildlife conservation from operating in mutually exclusive arenas (i.e., research or management). As a wildlife researcher whose research is conducted on both public and private rangelands, and across multiple stakeholder groups, techniques to answer difficult questions and offer time-sensitive solutions must pull from both research and management arenas. Historically, book or journal resources that wildlife professionals could readily access for necessary scientific guidance were contained in many documents, making …

Specificity Of Nifen And Vnfen For The Assembly Of Nitrogenase Active Site Cofactors In Azotobacter Vinelandii, Ana Pérez-González, Emilio Jimenez-Vicente, Jakob Gies-Elterlein, Alvaro Salinero-Lanzarote, Zhi-Yong Yang, Oliver Einsle, Lance C. Seefeldt, Dennis R. Dean

Chemistry and Biochemistry Faculty Publications

The nitrogen-fixing microbe Azotobacter vinelandii has the ability to produce three genetically distinct, but mechanistically similar, components that catalyze nitrogen fixation. For two of these components, the Mo-dependent and V-dependent components, their corresponding metal-containing active site cofactors, designated FeMo-cofactor and FeV-cofactor, respectively, are preformed on separate molecular scaffolds designated NifEN and VnfEN, respectively. From prior studies, and the present work, it is now established that neither of these scaffolds can replace the other with respect to their in vivo cofactor assembly functions. Namely, a strain inactivated for NifEN cannot produce active Mo-dependent nitrogenase nor can a strain inactivated for VnfEN …

Collaborative Research: Ecological Legacy Effects Of Megacarcasses In African Savanna Ecosystems, Johan Du Toit

Funded Research Records

No abstract provided.

What Is Biochar And How Is It Used?, Marion Murray

All Current Publications

Biochar is a charcoal-like product that contains no petroleum. It is made by heating biomass such as herbaceous or woody crop residues, non-salvageable timber, and slash, or animal manure, in a contained system. There are many potential uses for biochar including water treatment, land reclamation, and carbon sequestration. Biochar may also be used as a soil amendment for two purposes – to improve plant health and to store carbon.

Chinches, Kelly Kopp, Ryan Davis, Ricardo Ramirez, Celina Wille

All Current Publications

Las chinches son “chinches verdaderas”. En Utah, la chinche común [Blissus leucopterus leucopterus (Say)] y la chinche occidental (Blissus occiduus) pueden alimentarse del césped, especialmente en condiciones de calor intenso y sequía. La falta de riego, junto a la radiación directa y la acumulación de material vegetal muerto puede elevar el número de chinches desde mediados del verano hasta principios del otoño.

Changing Land Use And Population Density Are Degrading Water Quality In The Lower Mekong Basin, Flavia Tromboni, Thomas E. Dilts, Sarah E. Null, Sapana Lohani, Peng Bun Ngor, Savoeurn Soum, Zeb Hogan, Sudeep Chandra

Watershed Sciences Faculty Publications

Establishing reference conditions in rivers is important to understand environmental change and protect ecosystem integrity. Ranked third globally for fish biodiversity, the Mekong River has the world’s largest inland fishery providing livelihoods, food security, and protein to the local population. It is therefore of paramount importance to maintain the water quality and biotic integrity of this ecosystem. We analyzed land use impacts on water quality constituents (TSS, TN, TP, DO, NO3−, NH4+, PO43−) in the Lower Mekong Basin. We then used a best‐model regression approach with anthropogenic land‐use as independent variables and water quality parameters as the dependent variables, to …

Enhancing Existing Isolated Underpasses With Fencing Reduces Wildlife Crashes And Connects Habitat, Bridget M. Donaldson, Kaitlyn E. M. Elliott

Human–Wildlife Interactions

The impact of wildlife–vehicle collisions on drivers and wildlife populations has been gaining attention in the United States. Given the established success of wildlife crossings with fencing in reducing wildlife crashes and connecting habitat, information is needed on cost-effective means of implementation for departments of transportation. When wildlife crossings are constructed, they are often built into new road projects as a series of 2 or more underpasses and/or overpass structures connected by exclusionary fencing. Given limited transportation budgets and the prevalence of maintenance activities more so than new construction in many states, enhancing existing underpasses on previously constructed roads has …

Temporal Trends And Drivers Of Mountain Lion Depredation In California, Usa, Justin A. Dellinger, Daniel K. Macon, Jaime L. Rudd, Deana L. Clifford, Steven G. Torres

Human–Wildlife Interactions

Increasing human populations and expanding development across the globe necessitate continual progress in understanding and mitigating human–wildlife conflict. California, USA has the largest human population and at least half of the state is suitable mountain lion (Puma concolor) habitat. The juxtaposition of high human abundance within and adjacent to mountain lion habitat make California relevant for understanding human–large carnivore conflict. We compiled 7,719 confirmed incidents of mountain lions depredating domestic animals over a 48-year period (1972–2019) to examine temporal trends in mountain lion depredations as well as factors influencing annual depredation rates at the county level. Linear regressions …

New Associate Editors, Terry A. Messmer

Human–Wildlife Interactions

New associate editors for special topic submissions include Aaron B. Shiels, Shane R. Siers, and Marco Restani.

Availability And Structure Of Coarse Woody Debris In Hemiboreal Mature To Old-Growth Aspen Stands And Its Implications For Forest Carbon Pool, Silva Šēnhofa, Guntars Šnepsts, Kārlis Bičkovskis, Ieva Jaunslaviete, Līga Liepa, Inga Straupe, Āris Jansons

Aspen Bibliography

European aspen deadwood is extensively studied as a habitat for saproxylic species, while less is known of its dynamics and role in carbon sequestration. We studied unmanaged mature (41–60 years), moderately overmature (61–80 years), overmature (81–100 years), and old-growth (101–140 years) and managed mature and moderately overmature aspen stands on fertile mineral soils. In unmanaged stands, marginal mean CWD volume was from 67.3 ± 12.1 m³ ha⁻¹ in moderately overmature to 92.4 ± 5.1 m³ ha⁻¹ in old-growth stands, with corresponding marginal mean CWD carbon pool 8.2 ± 1.6 t ha⁻¹ and 12.5 ± 0.7 …