Life Sciences Commons^™

Nest Location And Nest Recognition In Two Solitary Bee Species Osmia Lignaria Say And Megachile Rotundata (F.) (Hymenoptera: Megachilidae), Christelle Guédot

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The visual and olfactory cues used in short-range orientation, specifically nest location and nest recognition, were studied in two solitary bee species Osmia lignaria Say and Megachile rotundata (F.) Osmia lignaria, the blue orchard bee, is an important pollinator of orchard crops, such as apples, cherries, and almonds; and M. rotundata, the alfalfa leafcutting bee, is used in commercial pollination of alfalfa. The general objective was to better understand how these two species locate their nests and how improving nest location could benefit crop pollination.

The use of proximal visual landmarks at the nesting site was investigated with …

Remote Sensing Of Sagebrush Community Structural Patterns Across Scales, Lisa A. Langs

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Throughout the Intermountain West there has been a substantial reduction in both the quantity and quality of sagebrush ecosystems. To assist current range management objectives, numerous efforts have been made to classify and map sagebrush communities using remotely sensed data. However, the amount of detail provided by these broad-scale mapping projects is often limited. This research evaluated the ability of a suite of airborne and satellite imagery to detect sagebrush community structural attributes, specifically percent canopy cover, live cover, density, size-vigor, and spatial arrangement of shrubs. Field data was collected at Camp Williams National Guard Training Facility near Bluffdale, Utah, …

Natural History, Demography, And Home Range Characteristics Of A Southern California Population Of Phrynosoma Mcallii Inhabiting Atypical Habitat, Kirk Setser

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Phrynosoma mcallii inhabiting a topographically complex, sparsely vegetated, "mudhill" terrain site in southern California in 1999 and 2000 had low mortality rates, and small clutch sizes compared to previous data from this species. Females likely produced a single clutch of eggs in each year. Although this population occurs near a heavily used OHV trail, I did not detect any mortality due to OHV use.

Lizards did not center home ranges on obvious habitat features. Lizards maintained smaller home ranges and exhibited greater range fidelity than did lizards at other sites in other years. Phrynosoma mcallii share many area-use characters with …

Response Of A Peatland Ecosystem To Stratospheric Ozone Reduction In Tierra Del Fuego, Thomas Matthew Robson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Tierra del Fuego, at the southernmost tip of South America, is influenced by ozone depletion. The landscape of southern and western Tierra de! Fuego is dominated by peatlands; they are important locally and in the context of global climate change, because they store large quantities of organic carbon.

To determine the influence of solar ultraviolet-B radiation (UV-B) on a Tierra de! Fuego peatland, we selectively filtered solar UV-Bin ten pairs of plots. Polyfluorine filters were used to create the Near-Ambient-UV-B Treatment (90% solar UV-B), and polyester filters to create the Reduced-UV-B Treatment ( 17% solar UV-B). These filters were first …

Influence Of Fall Grazing By Sheep On Plant Productivity, Shrub Age Class Structure And Herbaceous Species Diversity In Sagebrush Steppe, Ryan Duncan Woodland

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Traditional chemical and mechanical treatments of Wyoming Big Sagebrush (Artemisia tridentata ssp. wyomingensis) are costly and have typically focused solely on increasing forage for livestock production. Managing these systems biologically with grazing can potentially reduce costs and increase both biodiversity and understory production as well as rejuvenate Wyoming Big Sagebrush (ARTRWY). This experiment was conducted on Deseret Land and Livestock Ranch in northern Utah in October 2003. One hundred and twenty sheep (dry ewes) grazed 3, 60m x 40m plots (40 sheep plot^-1). Sheep were provided a protein-energy supplement to facilitate use of the secondary metabolites …

Nutrition And Bone Density In Children With Cystic Fibrosis, Joanna K. Davidson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The purpose of these studies was to further research on bone density in children with cystic fibrosis, particularly as it pertains to nutritional parameters and care. The first paper presented a comparison of a group of 50 children with cystic fibrosis to a group of 32 control children. There were no significant differences between the groups in any of the pertinent bone density measurements. Serum 25(OH) vitamin D was positively correlated with spine density z score in the cystic fibrosis group.

The second paper, incorporating all of the information obtained from the first paper, describes an intervention study with the …

Greenstrip Establishment And Management In The Intermountain West, Brenda Kristine Younkin-Kury

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Greenstrips were established at two sites in Utah to determine if seeded, grazed cool-season, perennial grasses would change fire behavior characteristics in areas currently dominated by Bromus tectorum. Frequency data were collected for both grazed and ungrazed seeded species and resident weed species. Moderate spring grazing did not negatively impact the establishment of seeded species at Camp Williams. Grazing at Promontory Point decreased Agropyron desertorum frequency and increased the frequency of Pascopyrum smithii. Biomass data collected for grazed and ungrazed treatments in both years indicated that moderate spring or winter grazing the first two years of establishment did …

Cougar Exploitation Levels In Utah: Implications For Demographic Structure, Metapopulation Dynamics, And Population Recovery, David C. Stoner

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Presently, eleven western states and two Canadian provinces utilize sport hunting as the primary mechanism for managing cougar (Puma concolor) populations. However, the impacts of sustained harvest on population dynamics and demographic structure arc not well understood. Additionally, the lack of cost-effective enumeration techniques and strongly conflicting societal values complicate effective management of this species. Given these concerns, the primary goals of this study were (I) to determine the effects of sustained harvest on cougar populations, and (2) estimate the level and extent of cougar harvest statewide.

I monitored cougar populations on Monroe Mountain in south-central Utah, and …

Role Of Iron In The Mechanism Of Asbestos-Induced Apoptosis In Human Lung And Pleural Target Cells, Aleksander Baldys

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Occupational exposure to asbestos has been associated with increased incidence of pulmonary interstitial fibrosis, mesothelioma of the pleura, and bronchogenic carcinoma. Although the mechanism by which asbestos causes cancer remains unknown, iron associated with asbestos is thought to play a role in the pathogenic effects of fibers.

The aim of this research was to examine and compare the asbestos-induced signaling phenomena in relevant human lung and pleural target cells, and to determine the role of iron from asbestos fibers in these events. Exposure of human airway epithelial (A549) cells, human pleural mesothelial (MET5A) cells, and normal human small airway epithelial …

Cultivation Of Mushroom Mycelia Using Whey Products As A Growth Substrate, Boyd S. Inglet

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

As part of a project designed to utilize common dairy waste products profitably, reconstituted dry whey permeate and delactosed whey were tested as growth substrates for mycelia of the edible mushroom Lentinus edodes. This mushroom was chosen because it is possible to profitably cultivate it due to its popular culinary appeal and perceived medical benefits.

Growth experiments were performed in petri dishes containing either reconstituted dry whey permeate or delactosed whey as a growth substrate, and the measured response was the size of the growing mycelia colony. When reconstituted dry whey permeate was utilized as a growth substrate, the …

Quantifying Losses Of Understory Forage In Aspen Stands On The Dixie And Fishlake National Forests, Barton R. Stam

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The West has lost up to 60% of its historic aspen stands over the last century, probably as a result of the successional tendency of aspen to be replaced by coniferous species in the absence of periodic fires. One of several major impacts of this change is the loss of understory forage as conifer canopy cover increases. I measured understory biomass in aspen stands ranging from 0% to 81 % absolute conifer cover in the canopy and found that understory production declines exponentially as conifers replace aspen. I also did an economic analysis to determine the value of the forage …

Cattle As Grazing Management And Seed Dispersal Tools For Increasing Native Species Diversity On Great Basin Rangelands, Marina K. Whitacre

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A series of experiments evaluated: 1) the influence of seed intake and gut retention time on seed passage, recovery, and germinability; 2) fecal seeding and broadcast /trampling as techniques to incorporate seeds into a well-established Agropyron desertorum (Fisch.) Schult. stand in Skull Valley , Utah; 3) intensive grazing as a means to reduce Agropyron biomass and increase establishment and survival of seeded species; and 4) the recovery and germinability of seed extracted from dung collected from the field. Two shrubs (Artemisia tridentata Nutt. ssp. wyomingensis Beetle & Young and Atriplex confertifolia Torr. & Frem.), a grass (Elymus elymoides (Raf.) …

Rapid Detection Of Salmonella Without Enrichment, Emily J. Harrington

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Salmonella is one of the leading foodborne pathogens causing illness today. Because of this, Salmonella rapid detection methods are under immense study for use in food. The traditional method, using the Food and Drug Administration- approved Bacterial Analytical Manual procedure, takes 4-6 days for Salmonella detection in food. Other rapid methods still take at least 16 h for detection due to their enrichment steps.

The hypothesis of this study was that the use of immobilized antibodies coupled with polymerase chain reaction (PCR) can be used for the rapid capture and detection of Salmonella spp. in food without the need for …

Investigation Of The Effect Of Sulfitolysis On The Functional Properties And Extrusion Performance Of Whey Protein Concentrate, David P. Taylor

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Whey proteins have restricted use in many food applications because of limited functional properties. Whey proteins' relatively high content of disulfide bonds may be responsible for their lack of functionality, especially in extrusion applications.

To determine the effect of disulfide bond content on functional properties and extrudate performance, whey protein concentrate was treated with sodium sulfite to achieve four levels of disulfide bond sulfonation (0, 31, 54, and 71%). Sulfonated whey protein functional properties, extrusion-expanded snack properties (32% total protein), and extrusion-textured fibrous product properties (48% protein) were determined. Correlation analysis was performed to determine relationships between functional properties and …

Influence Of Sodium Chloride, Calcium, Moisture, And Ph On The Structure And Functionality Of Nonfat Directly Acidified Mozzarella Cheese, Brian M. Paulson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Experiment A explored the influence of sodium on direct acid, nonfat Mozzarella cheese. Cheeses with differing salt levels were obtained by varying dry salt applications (none, 0.5%, and 1.0% NaCl w/w) and hot brine stretching (0%, 5%, and 10% NaCl wt/v). Salt application and salt content influenced cheese moisture, meltability, expressible serum, micro- and ultra-structure, and color. Moisture was highest when cheese was salted before stretching (P = 0.03). Melt was lowest in cheeses that were unsalted (P = 0.05). Cheeses stretched in salt brine had < 1% of the amount of expressible serum found in unsalted cheese (P < 0.0001). Unsalted cheeses had a more open structure with pockets of serum distributed throughout the protein matrix giving it an opaque, white appearance. Salted cheeses had a more homogeneous protein matrix lacking light scattering surfaces, resulting in a translucent cheese. Neither salt concentration nor method of salting affected the calcium content of the cheeses (P > 0.05).

Experiment B explored the influence of calcium, moisture, and …

Comparative Effects Of Sodium Levulinate And Sodium Lactate On Microbial Growth, Color, And Thiobarbituric Acid (Tba) Values Of Fresh Pork And Turkey Sausages During Storage, Mihir N. Vasavada

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This study compared the effects of 1.4 or 2.7% sodium levulinate or sodium lactate on aerobic plate count (APC), color, pH, and TBA value of fresh pork and turkey sausage. Both sodium lactate and levulinate inhibited growth of aerobic microorganisms during storage, compared to controls. Bacteriostatic effects of sodium lactate were dose dependent, wherein 2.7% lactate was significantly more antimicrobial than 1.4% lactate. This was not the case for sodium levulinate, where 1.4% sodium levulinate was as inhibitory to microbial growth as 2.7% sodium levulinate. Additionally, 1.4% sodium levulinate was as inhibitory to microbial growth as the higher level (2.7%) …

Assessment Of Calcium, Milk, And Non-Milk Beverage Intake Of Multiethnic Youth Aged 10 To 18 Years, J. Keith Jensen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Achieving and maintaining maximal peak bone mass is critical to the prevention of osteoporosis. Adequate calcium intake during youth is a major aspect of proper bone mass development. Because of the importance of calcium, a food frequency questionnaire (FFQ) that estimates calcium intake of 10- to 18-year-old Asian, Hispanic, and white youth living in the western United States was developed. This new FFQ was shown to accurately and reliably estimate calcium intake of these youth. Accuracy among Hispanics, however, was low and requires further evaluation. A second study examined intake of calcium, milk, and non-milk beverages of Hispanic and non-Hispanic …

Prevention Of Pigment Deterioration And Lipid Oxidation In Ground Beef And Pork, Preetha Jayasingh

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Fresh beef was modified-atmosphere packaged in carbon monoxide or oxygen to prolong red surface color. After comparison of several packaging method using carbon monoxide, steaks pretreated with 5% carbon monoxide for 24 hours and then vacuum packaged had the best combination of color and microbial stability (5 weeks), with the least potential for carbon monoxide inhalation.

In the evaluation of ground beef in high-oxygen, modified-atmosphere-packaging, thiobarbituric-acid numbers increased over time, and the flavor was disliked slightly after 6 or 10 days of storage at 2° Celsius.

The antioxidant effect of milk-mineral was tested in raw and cooked ground pork stored …

Effect Of Raw Lngredient Surface Area, Storage Time And Antioxidants On Color And Oxidative Stability Of Ground Beef In 80% Oxygen Modified Atmosphere Packaging, Avanthi Vissa

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Fresh beef packaged in high-oxygen modified atmosphere packaging (MAP) has longer red color stability than beef in oxygen-permeable polyvinyl chloride (PVC) film. However, fresh beef in high oxygen becomes rancid by 10 days storage at 2°C. Thus the objective of this study was to evaluate the effectiveness of various antioxidants (milk mineral, MM; sodium tripolyphosphate, STP; vitamin E, E) on color and thiobarbituric acid (TBA) values of ground chuck stored in 80% oxygen MAP for 14 days at 1° C. A preliminary experiment was also done to determine the effect of raw meat history (surface area during storage and storage …

Development And Characterization Of Eukaryotic Biomimetic Liposomes, Bradley Jay Taylor

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This study developed and characterized phospholipid vesicles, or liposomes, that mimic cell surfaces. Microemulsified liposomes contained biotinylated phosphatidylethanolamine, allowing them to be immobilized to avidin-coated glass. Laminin (LN), glycosphingolipids (GMl and GM3), and Escherichia coli's mechanosensitive channel of large conductance (EcoMscL) were embedded into liposome membranes. It was determined whether these embedded molecules exhibited their physiological roles of adhesion, cell recognition, and mechanosensation, respectively. Confocal laser scanning microscopy (CLSM) was employed to examine the interaction of fluorescently probed proteins, toxins, and bacteria with the immobilized microemulsified liposomes. Capture of individual and simultaneous multiple species of bacteria by GMl, GM3, …

Casein Supramolecules: Structure And Coagulation Properties, Bonney S. Oommen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The changes in quaternary structure of casein supramolecules with various physical and chemical treatments were studied using transmission electron microscopy, and a model to account for the changes is put forth. The effects of casein structure on coagulation properties were also studied. The sample preparation for transmission electron microscopy involved physical methods of fixation and flash freeing to preserve the structure of caseins in the sample.

The structure of caseins in sodium and calcium caseinate varied with sodium caseinate not exhibiting any spherical structure as opposed to the spherical structure seen in calcium caseinate, non-fat dried milk and native milk. …

Voluntary And Involuntary Weight Change And Risk Of Osteoporotic Hip Fracture In Men And Women Of Utah, Megan Ruth Mcdonough

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Change in body weight is an important determinant of risk of osteoporotic hip fracture in aging adults. Weight loss has been associated with an increased risk of hip fracture and weight gain has been associated with a decreased risk of hip fracture. Weight gain cannot be recommended as appropriate prevention against hip fracture, however, because it is associated with such adverse health outcomes as cardiovascular disease and diabetes, and weight loss is commonly recommended in the treatment of these types of diseases. Clarification of how weight loss is related to risk of hip fracture is needed to resolve this issue. …

Hormone Mediated Transport Of Calcium And Phosphate In Polarized Epithelial Cells, Tremaine M. Sterling

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The effects of 1,25(OH)₂D₃, PTH and 25(OH)D₃ on phosphate or calcium uptake were studied in cultured, adherent chick enterocytes over a period of 10 min after hormone addition. Time course studies of cells treated with 130 pM 1,25(OH)₂D₃ showed an increase in ³²P uptake as early as 3 min. Similar studies with 65 pM bPTH(l1-34) resulted in an increase in ⁴⁵Ca uptake only if the cells had been cultured in serum. (OH)D₃, which is not firmly established as an active metabolite of vitamin D, was shown to increase …

Host Shifts In Phytophagous Insects: A Mathematical Modeling Perspective, Meenakshi Venkataraman

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

I explored changes in predator-prey system stability with the addition of spatial heterogeneity in prey density dependent mortality. The results indicated that this addition led to greater stability for all prey spatial distributions if prey was aggregated or loosely aggregated. These results indicated prey spatial distribution was critical to population stability. I next explored whether predator emigration under the above conditions would lead to a host shift. I used Chesson and Murdoch's templates of host density independent (HDI) aggregation and host density dependent (HDD) aggregation in predators as the basis for my metapopulation models. I varied prey density dependent mortality …

Snow Avalanche Disturbance In Intermountain Spruce-Fir Forests And Implications For The Spruce Bark Beetle (Coleoptera: Scolytidae), Elizabeth G. Hebertson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Spruce beetle outbreaks are the primary biotic disturbance affecting forests in the Intermountain spruce-fir zone. Major snow avalanches can produce large quantities of host material for spruce beetle colonization; however, few studies have examined the influence of avalanche disturbance on outbreak initiation. The purpose of my research was to investigate potential relationships between these two disturbance agents. In the first study, I used dendro-ecological analyses to date major avalanche years on the Wasatch Plateau in south-central Utah, and then determined what climate factors were associated with avalanche occurrence. The results indicated that mean January snowfall was significantly related to the …

Feeding Behavior Of Sheep In Relation To Kinetics Of Sagebrush Monoterpenes: Implications For Landscape Biodiversity, Luthando E. Dziba

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The sagebrush steppe is one of the most extensive vegetation types in the western US and an important habitat for wild and domestic herbivores. When sagebrush dominates, however, forage and habitat quality decline. Although sagebrush is nutritious, its forage value is reduced by terpenes. A better understanding of how terpenes limit intake is vital for increasing consumption of sagebrush and for enhancing and maintaining biodiversity in the sagebrush-steppe.

To better understand how terpenes in sagebrush limit intake, we studied feeding behavior of sheep in the field, influence of sagebrush monoterpenes on regulation of intake in pens, and the feeding behavior …