Life Sciences Commons^™

Historical Biogeography Of Velvet Ants (Hymenoptera: Mutillidae) In The North American Deserts And Arid Lands, Joseph S. Wilson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

For centuries, scientists have been intrigued by the high amount of biodiversity that is found in the deserts of North America. Recently, several studies have investigated the causes of the high diversity found in desert-dwelling mammals, reptiles, and amphibians. These studies have found that many of these organisms seem to have diversified in response to the same historical events. Little work has been done, however, on diverse desert-dwelling insect groups. In this dissertation, I investigate the patterns of genetic diversity in four groups of nocturnal wasps called velvet ants. I compare the patterns of genetic diversity to the historical events …

Assessment Of Ruminal Fermentation Characteristics Of Condensed Tannin-Containing Forages Using Continuous Cultures, Christina Marie Williams

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Two independent studies were conducted to assess the effects of feeding condensed tannin (CT)-containing forages to continuous cultures to evaluate their impacts on ruminal fermentation and digestibility, with an emphasis on methane (CH4) and ammonia-N (NH3-N) production. In Chapter 3, treatments consisted of: 1) 100% alfalfa hay (AH), 2) 50% AH and 50% birdsfoot trefoil hay (dry matter (DM) basis; AHBFTH), and 3) 100% birdsfoot trefoil hay (BFTH). Three replicated runs lasted 8 d each, with the first 5 d allowed for microbial adaptation to the diets, and 3 d for data collection and sampling. Methane, neutral detergent fiber (NDF) …

Establishment And Aesthetic Value Of Native Grass, Legume, And Forb Species For Grassland Restoration In The Northern Intermountain West, Bridget M. Atkin

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Interest in the restoration of landscapes native to the Intermountain West is growing as the value of these arid ecosystems is increasingly recognized. Many landscapes within the Intermountain region have been impacted by grazing, development, recreation, and other human-caused disturbances. The complex relationships within the native plant communities of these arid landscapes need to be well-understood biologically, while considering their aesthetic contribution, if restoration efforts are to succeed. Although the use of ecologically appropriate native species is increasing in popularity, there is discontinuity between aesthetics and meaningful ecological contributions. A series of studies was designed to aid in the restoration …

Ecology And Management Of A High Elevation Southern Range Greater Sage-Grouse Population: Vegetation Manipulation, Early Chick Survival, And Hunter Motivations, Michael R. Guttery

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

My research provided new information concerning the management, ecology, and conservation of greater sage-grouse (Centrocercus urophasianus). I report the results of an experiment using strategic intensive sheep grazing to enhance the quality of greater sage-grouse brood-rearing habitat. Although forb cover, an important component of brood-rearing habitat, responded positively to the grazing treatment, the response of other habitat variables was suppressed because the plots were not protected from domestic and wild herbivores during the years following the treatments. Measurements taken in grazing exclosures confirmed that herbivory by both large and small animals had significant impacts on vegetation. However, despite …

Interclonal Variation Of Primary And Secondary Chemistry In Western Quaking Aspen And Its Influence On Ungulate Selection, Damon A. Winter

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Quaking aspen (Populus tremuloides) clones within close proximity to one another can exhibit drastically different levels of browsing by ungulates. The objectives of this study were to (1) determine interclonal differences in plant chemistry between adjacent clones exhibiting different degrees of herbivory which may influence the browsing behavior and patterns of ungulates, and (2) determine if correlation exists in the levels of salicortin and tremulacin between current year's suckers and current year's growth on older trees. This second objective was meant to indicate a protocol for land managers for identifying clones meriting increased protection from herbivory after treatment …

The Status Of Dwarfed Populations Of Short-Horned Lizards (Phrynosoma Hernandesi) And Great Plains Toads (Anaxyrus Cognatus) In The San Luis Valley, Colorado, Megan E. Lahti

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The San Luis Valley is a large valley formation in Colorado surrounded on either side by mountain ranges exceeding 4,267 m. Within the Valley, two of the 14 amphibian and reptile species are dwarfed: the short-horned lizard (Phrynosoma hernandesi) and the Great Plains toad (Anaxyrus cognatus). Since its initial reporting in 1968 and confirmation in 1981, no research further investigating this dwarfism has been conducted. I collected morphological measurements to determine the extent and patterns of dwarfism of both species. I then investigated the genetics of both species using mitochondrial DNA to determine whether they are …

Maporal Hantavirus Β-Integrin Utilization And Sensitivity To Favipiravir, Kristin K. Buys

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Hantaviruses are members of the Bunyaviridae family of viruses. Pathogenic hantaviruses are the etiologic agents of hemorrhagic fever with renal syndrome (HFRS), a disease principally endemic in the Old World, and hantavirus pulmonary syndrome (HPS), a disease primarily restricted to the Americas. Maporal virus (MPRLV), a recently isolated hantavirus, has been found to cause disease in hamsters that resembles HPS in humans. However, the virus has not been linked to human cases of HPS. Considerable evidence suggests that β-integrin usage mediating infection may serve to distinguish hantaviruses pathogenic to humans from nonpathogenic, but this receptor usage pattern information is not …

Kinetic, Mechanistic, And Structural Investigation Of Features Controlling Stereoselectivity Of (R)- And (S)-Hydroxypropyl Com Dehydrogenases From Xanthobacter Autrophicus Strain Py2, Dariusz Adam Sliwa

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Enantiopure alcohols are valuable intermediates in fine organic synthesis, in particular for preparation of biologically active compounds. The necessity of preparing single enantiomer drugs in an optically pure form has triggered much research, especially in the pharmaceutical industry. The biocatalytical production of chiral alcohols by alcohol dehydrogenase enzymes is characterized by the asymmetric reduction of the corresponding ketones, usually with high degree of stereoselectivity. The commercial value of the enzymes as stereoselective biocatalysts has been a significant driving force in understanding features that control their mechanism of catalysis and stereoselectivity. This work focuses on two enantiocomplementary dehydrogenase enzymes ((R …

Dietary Milk Fat Globule Membrane Reduces The Incidence Of Aberrant Crypt Foci In Fischer-344 Rats And Provides Protections Against Gastrointestinal Stress In Mice Treated With Lipopolysaccharide, Dallin R. Snow

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Milk fat globule membrane surrounds the fat droplets of milk. It is a biopolymer containing primarily membrane glycoproteins and polar lipids which contribute to its properties as a possible neutraceutical. The aims of the studies were to determine if dietary milk fat globule membrane: (1) confers protection against colon carcinogenesis; and (2) promotes gut mucosal integrity while decreasing inflammation compared to diets containing corn oil or anhydrous milk fat.

Aim 1. Three dietary treatments differing only in the fat source were formulated: (1) AIN-76A, corn oil; (2) AIN-76A, anhydrous milk fat; and (3) AIN-76A, 50% milk fat globule membrane, 50% …

An Investigation Of The Utilization Of Soil Water And Nitrogen Among Diverse Forage Plant Species And Mixtures, Sallee Reynolds

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Species diversity achieved by adding novel functional groups (warm-season grasses and non-leguminous forbs) to pasture land, along with traditional grasses and legumes, could aid in the capture of nutrients and water in pasture systems by offering complementary rooting architecture to aid in water and nitrogen uptake and decrease nitrogen leaching. Because these species may differ from commonly used grasses and legumes in their seasonal pattern of productivity, they could also extend or enhance growing-season productivity. The goal of this project is to better understand the role of plant diversity in 1) nitrogen use and 2) distribution of rooting dynamics and …

Pervasive Thermal Consequences Of Stream-Lake Interactions In Small Rocky Mountain Watersheds, Usa, Jessica D. Garrett

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Limnologists and stream ecologists acknowledge the fundamental importance of temperature for regulating many ecological, biological, chemical, and physical processes. I investigated how water temperatures were affected by hydrologic linkages between streams and lakes at various positions along surface water networks throughout several headwater basins in the Sawtooth and White Cloud Mountains of Idaho (USA). Temperatures of streams and lakes were measured for up to 27 months in seven 6 – 41 km² watersheds, with a range of lake influence. When they were ice-free, warming in lakes resulted in dramatically warmer temperatures at lake outflows compared to inflow streams (midsummer …

Effect Of Mica Content On Surface Infiltration Of Soils In Northwestern Kern County, California, Steven Keyes Stakland

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A soils infiltration rate (IR) is the measured rate that soil is able to absorb water, either from precipitation or irrigation. A low IR can cause damage to crops if the necessary amount of water cannot penetrate to the plant roots in the time needed. The damage can be common in permanent plantings such as almond and pistachio orchards where regular tillage is avoided. This indicates a physical aspect to the problem because tillage increases IR. However, there is also an electrochemical side to infiltration problems because certain calcium surfactant treatments can increase IR. Various other methods have been used …

Selecting And Propagating Clones Of Bigtooth Maple (Acer Grandidentatum Nutt.), Melody Reed Richards

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Numerous wild bigtooth maple (Acer grandidentatum Nutt.) specimens in northern Utah have potential for use in landscapes, but improvements in selection and propagation need to be developed before these specimens can be introduced to the green industry. Criteria-based evaluations centered on aesthetics, function, and fall color were performed to objectively select superior bigtooth maple specimens. Out of 56 trees initially selected for red fall color, six were selected for propagation based on all three criteria. Five of the six selected trees yielded viable bud take via chip budding. Optimum time for chip budding propagation was determined by four experiments. …

Enhancing Out-Of-Season Production Of Tomatoes And Lettuce Using High Tunnels, Britney L. Hunter

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The growing season for vegetable crops is limited by freezing temperatures in arid high elevation climates such as northern Utah. Logan, Utah (41.73 N, 111.83 W, 1382 m elevation) has a short, variable growing season with an average frost-free period of 135 days. Extending the growing season provides growers with an opportunity to extend revenue into a normally unproductive period and benefit from out-of-season price premiums. High tunnels have been used to effectively extend the growing season for numerous crops by providing cold temperature protection. However, limited high tunnel research has been performed in arid high elevation regions that experience …

Phenotypic And Genetic Characterization Of Wildland Collections Of Western And Searls Prairie Clovers For Rangeland Revegetation In The Western Usa, Kishor Bhattarai

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Western prairie clover [Dalea ornata (Douglas ex Hook.) Eaton & J. Wright] is a perennial legume that occurs in the northern Great Basin, Snake River Basin, and southern Columbia Plateau, whereas Searls prairie clover [Dalea searlsiae (A. Gray) Barneby], also a perennial legume, occurs in the southern Great Basin and surrounding areas. Understanding the genetic and ecotypic variation of these prairie clovers is a prerequisite for developing populations suitable for rangeland revegetation in the western USA. DNA sequences of internal transcribed spacer (ITS/5.8S) and trnK/matK were used to study the phylogeny of these species. The species were distinguished …

Assessing Linkages Among Landscape Characteristics, Stream Habitat, And Macroinvertebrate Communities In The Idaho Batholith Ecoregion, Andrew C. Hill

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Understanding the composition of lotic communities and the landscape processes and habitat characteristics that shape them is one of the main challenges confronting stream ecologists. In order to better understand the linkages among landscape processes, stream habitat, and biological communities and to understand how accurately our measurements represent important factors influencing biological communities, it is important to test explicit hypotheses regarding these linkages. Increasing our understanding of aquatic communities in a hierarchical context and recognizing how well our measurements represent factors structuring aquatic communities will help managers better evaluate the influence of land management practices on aquatic ecosystems, direct conservation …

Native Bunchgrass And Invasive Weed Establishment In Low Nutrient Rangeland Soils With Nitrogen And Phosphorus Manipulation, Jeffrey S. Burnham

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Competition between native perennial grasses and Bromus tectorum has been studied for many years. Recently, soil nutrients have been immobilized in an effort to preferentially inhibit growth of B. tectorum relative to native species. Most of this work has focused on soil N, but interactions with soil P are less studied and may be important as well. Additionally, although competitive effects and nutrient responses of several Centaurea spp. are well documented, data are lacking on the competitive effects that Centaurea virgata exerts on the establishment of native and exotic communities. A field experiment and a greenhouse experiment were conducted to …

Season Extension Of Strawberry And Raspberry Production Using High Tunnels, Daniel R. Rowley

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

High tunnels have been used successfully in many areas of the world to extend the growing season for numerous crops. However, very little research has been conducted to evaluate the season extension benefits offered by high tunnels to small fruit crops in high elevation growing areas such as the Intermountain West region of the United States. The use of high tunnels was investigated in North Logan, Utah (41.766 N latitude, 1405 m elevation, 119 freeze free days) to extend the growing season for both strawberries and raspberries. June-bearing 'Chandler' strawberries in a fall-planted annual hill system were evaluated for early …

Evaluation Of Semiochemical Strategies For The Protection Of Whitebark Pine Stands Against Mountain Pine Beetle Attack Within The Greater Yellowstone Ecosystem, Greta Katherine Schen-Langenheim

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

High-dose verbenone, verbenone plus nonhost volatiles (NHVs), and both semiochemicals in combination with aggregant-baited funnel traps were tested for stand- level protection against mountain pine beetle attack for two consecutive years (2004-2005) at three seral high elevation whitebark pine sites in the Greater Yellowstone Ecosystem. In 2004, two 0.25-hectare treatments comprised of 25 high-dose verbenone pouches or verbenone pouches combined with single baited funnel traps were tested in a push-pull strategy. In 2005, 25 high-dose verbenone and 25 NHV pouches, or verbenone and NHV in combination with baited funnel trap clusters were tested. In both years, treatments were compared to …

Physiological And Molecular Function Of Hap3b In Flowering Time Regulation And Cold Stress Response, Mingxiang Liang

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Heme-activated proteins (HAPs) are transcription factors that have multiple roles in plant growth and development, such as embryogenesis, flowering time control, and drought tolerance.

In the present study I found that HAP3b was also involved in controlling response to cold stress. Transcript profiling and gene expression analyses indicated that HAP3b repressed the CBF3 regulon under normal growth conditions. As a result, plants with HAP3b-overexpressed showed decreased survival rates while plants homozygous for the null allele hap3b showed an improved freezing tolerance compared to wild-type plants.

To understand the mechanism of HAP3b in Arabidopsis, i.e. whether it also acts …

Assessing Quaking Aspen (Populus Tremuloides) Decline On Cedar Mountain In Southern Utah Using Remote Sensing And Geographic Information Systems, Chad M. Oukrop

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Quaking aspen (Populus tremuloides Michx.) is the most widespread deciduous tree species in North America and aspen ecosystems are highly valued for multiple use, being noted for forage production, understory diversity, wildlife habitat, timber, hydrological assets, and aesthetics. However, aspen communities in the Intermountain Region of the western United States are in evident decline, with certain areas experiencing rapid mortality over the past decade. One location of special interest is the quaking aspen on Cedar Mountain in Southern Utah, USA, an isolated population in the southwestern portion of aspen's geographic range.

Lacking critical information on the location, extent, and …

Host Signaling Response To Adhesion Of Bifidobacterium Infantis, Reed N. Gann

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Investigations of the molecular binding partners of the probiotic bacterium Bifidobacterium longum subspecies infantis (B. infantis) and the pathogen Salmonella enterica subspecies enterica serovar Typhimurium LT2 (Salmonella ser. Typhimurium) found that these two very different bacteria bind gangliosides. However, these organisms lead to completely different host health outcomes when present in the gut. B. infantis is the founding microbial population in the intestinal tract of breast-fed infants. S. typhimurium is the most important food-borne pathogen that results in humans. This study used an in vitro gut epithelial cell model to examine the host cellular response to adhesion …

Plastic And Genetic Determination Of Population, Community, And Ecosystem Properties In Freshwater Environments, Leigh C. Latta Iv

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The hierarchy of biological organization, from molecules to ecosystems, describes the relationships among various biological systems. Of particular interest is assessing how the factors that primarily determine the nature of one hierarchical level also have transcendent qualities that affect the ecology and evolution of higher hierarchical levels. The goal of this dissertation was to use a bottom-up approach to examine the transcendent effects of two factors that strongly determine the nature of their associated level of biological organization. The first, phenotypic plasticity, is a primary factor that determines the phenotype of an individual. The second factor, genetic diversity, largely determines …

Object-Based Segmentation And Classification Of One Meter Imagery For Use In Forest Management Plans, W. Kevin Wells

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This research developed an ArcGIS Python model that extracts polygons from aerial imagery and assigns each polygon a vegetation type based on a modified set of landcover classes from the Southwest Regional Gap Analysis Project. The model showed an ability to generate polygons that accurately represent vegetation community boundaries across a large landscape. The model is for use by the Utah Division of Forestry, Fire, and State Lands to assist in the preparation of forest management plans. The model was judged useful because it was easy to use, it met a designated 50% threshold of useable polygons, and it met …

Identifying And Understanding The Spatial Distribution Of Bobcat And Coyote Behavior, Ryan Radford Wilson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A common observation in animal space use studies is that animals do not use space uniformly, but rather use some areas of their home ranges and territories with much higher intensity than others. Numerous methods have been developed to estimate these "core areas"; however, all of the current methods available are based on arbitrary rules. Additionally, most studies do not attempt to understand what behavioral processes lead to the observed patterns of non-uniform space use. This study has four main objectives: 1) to develop an objective and more precise method for estimating core areas, 2) to understand the processes leading …

Targeting Fatty Acid-Activated Pathways In The Somatosensory System, Tian Yu

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Given the dramatic rise in obesity and the diseases linked with it, it is becoming increasingly important to understand the mechanisms that underlie the body's ability to recognize fat. The chemoreception of dietary fat in the oral cavity has largely been attributed to activation of the somatosensory system that relays the textural properties of fat. However, the ability of fatty acids, which are believed to represent the proximate stimulus for fat taste, to activate trigeminal ganglionic neurons has remained unexplored. In general, my research has provided the first evidence of fatty acids activating the somatosensory system by increasing the intracellular …

Natural History And Breeding System Of Maguire Primrose, Jacob B. Davidson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The goal of this thesis was to examine the breeding system and natural history of the Maguire primrose (Primula cusickiana var. maguirei). Maguire primrose is an endemic, threatened subspecies found only along a narrow corridor within Logan Canyon in northern Utah, USA. This plant displays distinct flower distyly, with clear distinction of pin and thrum morphologies (morphs). The timing of Maguire primrose flower blooms was disparate between upper and lower canyon populations, and the flowers experienced cool temperatures occasionally. I captured eight different species of flying insects visiting Maguire primrose flowers, and made 67 observations of insect visitation. …

The Influence Of Collective Action And Policy In The Development Of Local Food Systems, Lori Porreca

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The modern global agrifood system has had significant negative impacts on consumers and producers. This has precipitated the rise of local food systems that are purported to improve the health and livelihoods of consumers and producers. High expectations have led to significant public and private resources dedicated to the development of local food systems. Despite this, there has been little systematic research exploring the social and institutional conditions that facilitate or frustrate local food system development.

Using a comparative case study approach, this study explored the ways local structural conditions, collective action, food system policies, and the political context affect …

Financial Feasibility Of High Performance Low Rise Steel Buildings, Yolanda Maria Baez Batista

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Comparative performance evaluation including life cycle cost is currently being conducted on a series of conventional and base-isolated case study buildings. Alternative design approaches and their influence in cost were to be evaluated. This investigation is intended to contribute in the development of isolated structures by allowing engineers to communicate the cost of higher performance systems to their clients. The reported effort is part of a larger cost-benefit study for isolated steel buildings, and the purpose of this thesis is to compare initial investment of 3-story conventional and isolated steel buildings and determine how isolation affects the cost of the …

Biological And Mechanical Approaches To Sunscald Management In Bell Pepper Production, Samuel D. Day

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Producing red bell peppers in high temperature and light environments can be challenging because many new semi-indeterminate varieties produce small plant canopies that leave fruit exposed to damage (sunscald) caused by solar radiation. Pepper production in Utah coincides with high air temperatures and solar radiation levels during July, August, and September. Increasing plant canopy size is one way to protect fruit from solar radiation. Low tunnels optimize plant growth by increasing air and soil temperatures. Growing plants under low tunnels early in the season could increase fruit shading later in the season. Another way to protect fruit is by using …