Life Sciences Commons^™

The Water Table, Soil Moisture And Evapotranspiration Conditions Following The Removal Of Conifers From Two Encroached Meadows, Tyler J. Davis

Master's Theses

Montane meadows provide essential habitat for a variety of unique species and important ecosystem services in the western United States. Although important, meadows have experienced increased rates of conifer encroachment due to climate change, fire suppression and grazing. To combat meadow degradation from conifer encroachment, land managers have employed various restoration strategies one of which is conifer removal. Multiple studies have investigated the relationship between meadow hydrology and vegetation; however, few have assessed the effect of conifer removal on meadow groundwater. The goal of this study is to determine if the removal of conifers from an encroached meadow has an …

Evaluation Of Pheromone Mating Disruption For California Red Scale Control In Commercial California Citrus, Joel Timothy Leonard

Master's Theses

California red scale (CRS), Aonidella aurantii, is an increasingly injurious insect pest for the California citrus industry due to insecticide resistance, changing weather patterns, and shifting trade regulations. The presence of the insect on fruit, damages the rind of the fruit and high populations can cause dieback of branches as well as lower yields. Pheromone mating disruption of CRS has the potential to alleviate population control concerns and reduce insecticide use. The efficacy of the pheromone mating disruption technique for pest management of CRS was determined using the products CheckMate® CRS and Semios CRS Plus. CheckMate® CRS was evaluated …

Effects Of Intertidal Position On Metabolism And Behavior In The Acorn Barnacle, Balanus Glandula, Kali Horn

Master's Theses

The intertidal zone is characterized by persistent, tidally-driven fluctuations in both abiotic (e.g., temperature, [O₂], salinity) and biotic (e.g., food availability, predation) conditions, which makes this a very physiologically challenging habitat for resident organisms. The magnitude and degree of variability of these environmental stressors differs between intertidal zones, with the most extreme physiological stress often being experienced by organisms in the high intertidal. Given that many of the fluctuating conditions in this environment are primary drivers of metabolic rate (e.g., temperature, [O₂], food availability), we hypothesized that sessile conspecifics residing in different tidal zones would exhibit …

The Democratization And Development Of Cell-Free Protein Synthesis, Max Z. Levine

Master's Theses

Cell-free protein synthesis (CFPS) using crude lysates has developed into a robust platform technology over the last 60 years to express numerous types of recombinant proteins. The open-nature, elimination of reliance on cell viability, and focus of all energy towards production of the protein of interest represent substantial advantages of CFPS over in vivo protein expression methods. CFPS has provided new opportunities across a series of research fields that include metabolic engineering, therapeutic and vaccine development, education, biosensors, and many more. In recent years, optimizations of CFPS have even allowed the platform to reach the industrial level of protein production. …

Diet Quality And Micronutrient Intake In Long-Term Weight Loss Maintainers, Rebecca W. Pascual

Master's Theses

Objective: This study’s purpose was to examine dietary quality, macronutrient intake, and micronutrient adequacy among long term weight loss maintainers (WLM) in a commercial weight management program.

Methods: Participants were 1,207 WLM in WW (formerly Weight Watchers) who had maintained a 9.1 kg or greater weight loss (29.7 kg on average) for 3.4 years, and had an average BMI of 28.3 kg/m². A control group of weight stable adults with obesity (Controls; N=102) had a BMI of 41.1 kg/m² and 2.3 kg or less weight change over the previous five years.

Results: WLM vs. …

Evaluation Of Chilling Efficiency, Meat Tenderness, And Microbial Analysis Of Broiler Carcasses Using Sub-Zero Saline Solutions, Samira Viliani

Master's Theses

The poultry industry is seeking an advanced chilling system that can improve chilling efficiency, microbial safety, and water consumption without compromising meat quality. The objective of this study was to evaluate the effects of sub-zero saline chilling methods on chilling efficiency, breast fillet tenderness and microbial reduction of broiler carcasses. Following evisceration and rinsing, broiler carcasses were randomly assigned to one of three chilling solutions: 1) 0% salt or ice water control (0% NaCl/0.5^oC), 2) 3% salt (3% NaCl/-1.8^oC), and 3) 4% salt (4% NaCl/-2.41^oC) solutions. Broiler carcasses in sub-zero saline solutions reached the …

The Effects Of Cluster Thinning On Vine Performance, Fruit, And Wine Composition Of Pinot Noir (Clone 115) In The Edna Valley Of California, Paul F W Mawdsley

Master's Theses

A three-year study was conducted at a commercial vineyard site in California’s Edna Valley AVA to evaluate the physiological and agronomical effects of the timing of cluster thinning on Pinot noir (clone 115) grapevines. Vines were thinned to one cluster per shoot at three selected time-points during the growing season (bloom, bloom + 4 weeks, bloom + 8 weeks), and fruit from each treatment was harvested and made into wine. Across all growing seasons, yield decreased 43% in thinned vines relative to un-thinned control vines. No effect of cluster thinning or interaction with growing season was found in vine shoot …

Infestation Intensities, Attachment Patterns, And The Effect On Host Contest Behavior Of The Tick Ixodes Pacificus On The Lizard Sceloporus Occidentalis, Dylan M. Lanser

Master's Theses

Parasites often have profound effects on the survival and evolution of their hosts, and hence on the structure and health of entire ecosystems. Yet basic questions, such as the degree of virulence of a given parasite on its host, and factors influencing which hosts in a population are at the greatest risk of infection, are vexingly difficult to resolve. The western blacklegged tick-western fence lizard (Ixodes pacificus-Sceloporus occidentalis) system is important, primarily because I. pacificus, a vector of the Lyme disease spirochete Borrelia burgdorferi, is dependent on S. occidentalis for blood meals in its subadult stages, …

Examining The Effectiveness Of Electromyography Biofeedback At Improving The Upper Trapezius To Serratus Anterior Muscle Activation Ratio, Julia Evelyn Holton

Master's Theses

Purpose: The upper trapezius to serratus anterior muscle activation ratio is essential for optimal shoulder function. An alteration of this ratio, specifically a decrease in upper trapezius and increase in serratus anterior activation, is a main area of focus in shoulder rehabilitation (Kibler, 1998; Paine & Voight, 1993). Electromyography (EMG) biofeedback has been shown to be an effective rehabilitation technique to address many musculoskeletal disorders but there is limited research on the retention of improvements seen with EMG biofeedback (Ma et al., 2011; Lim et al., 2014; Weon, et al., 2011). The purpose of this study was to determine if …

Effects Of Sudangrass Cover Crop And Soil Solarization On Weed And Pathogen Management In Organic Strawberry Production, Timothy Jacobs

Master's Theses

Field and lab experiments were conducted to determine the efficacy of sudangrass (Sorghum X drumondii (Nees ex Steud.) Millsp. & Chase) cover crop management techniques and soil solarization on important agricultural weeds and pathogens in organic strawberry production in Central California. Lab experiments assessed the time needed to kill weed seeds at temperatures typically achieved during soil solarization (40°C, 45°C, 50°C, 55°C, and 60°C) in California. Seeds tested included little mallow, redstem filaree, bristly oxtongue, annual sowthistle, common purslane, nettleleaf goosefoot, and redroot pigweed. Efficacy of simulated …

Short Term Shifts In Soil Nematode Food Feb Structure And Nutrient Cycling Following Sustainable Soil Management In A California Vineyard, Holly M. Deniston-Sheets

Master's Theses

Evaluating soil health using bioindicator organisms has been suggested as a method of analyzing the long-term sustainability of agricultural management practices. The main objective of this study was to determine the effects of vineyard management strategies on soil food web structure and function, using nematodes as bioindicators by calculating established nematode ecological indices. Three field trials were conducted in a commercial Pinot Noir vineyard in San Luis Obispo, California; the effects of (i) fertilizer type (organic and inorganic), (ii) weed management (herbicide and tillage), and (iii) cover crops (high or low water requirements) on nematode community structure, soil nutrient content, …

Development Of A Prolyl Endopeptidase Expression System In Lactobacillus Reuteri To Reduce The Clinical Manifestation Of Celiac Disease, Kara Lynn Jew

Master's Theses

Celiac Disease (CD) is an autoimmune disorder that emerges due to the ingestion of gluten, a protein found in a variety of common grains such as wheat, rye, and barley. Approximately 1 in 100 individuals in the US suffer from CD, making it the most commonly diagnosed gastrointestinal disorder (Ciclitira et. al., 2005). These proline-rich gluten peptides are resistant to proteolysis and accumulate in the duodenum of the small intestine. Once in the duodenum, these peptides illicit an autoimmune response resulting in villous atrophy. Current treatment for CD requires a rigorous adherence to a gluten-free diet. Nevertheless, gluten-containing grains are …

Integrated Aeration For Enhanced Nitrogen Conversion And Removal And The Effect Of Sampling Frequency On Productivity Estimates In Algae-Based Wastewater Treatment Systems, Lauren Parker

Master's Theses

Raceway ponds can be used to cultivate microalgae for purposes such as wastewater treatment and feedstock for animal feeds and biofuels. Besides nitrogen assimilation in biomass, nitrification can be a wastewater treatment mechanism but one that is hindered by the low nighttime dissolved oxygen concentrations (DO) common in wastewater treatment raceways. The large diel difference in pond conditions and changing influent wastewater quality also raises the question of the optimal frequency and timing of grab sample collection, to obtain representative water quality data. Three sets of triplicate pilot raceways (1,000-L, 0.30-m deep, fed primary clarifier effluent) were operated at an …

An Analysis Of Changes In Stream Temperature Due To Forest Harvest Practices Using Dhsvm-Rbm, Julia B. Ridgeway

Master's Theses

Forest harvesting has been shown to cause various changes in water quantity and water quality parameters, highlighting the need for comprehensive forest practice rules. Studies show a myriad of impacts to ecosystems as a result of watershed level changes, such as forest harvesting. Being able to better understand the impact that forest harvesting can have on stream temperature is especially critical in locations where federally threatened or endangered fish species are located. The overall goal of this research project is to assess responses in stream temperature to various riparian and forest harvest treatments in a maritime, mountainous environment. The results …

Leaf Functional Traits As Predictors Of Drought Tolerance In Urban Trees, Sophia Huang

Master's Theses

The services that urban trees provide to human society and the natural environment are widely recognized, but urban trees are in jeopardy due to climate change and urban stressors. With drought as a major threat in many areas, it is important for the future of urban forestry to select species composition based upon performance under water stress. Certain leaf functional traits can help horticulturalists more accurately predict water usage of urban trees. Comprehension through rigorous experimentation is lacking, partly due to the thousands of mostly exotic species. Previous studies suggest that species whose leaves have a denser arrangement of smaller …

Dna And Protein Sequence Analysis Of Neuronal Markers Neuronal Nuclei (Neun) And Doublecortin (Dcx) In The Northern Pacific Rattlesnake (Crotalus Oreganus) And Western Fence Lizard (Sceloporus Occidentalis)., Brett M. Vassar

Master's Theses

Neuronal Nuclei (NeuN) and Doublecortin (DCX) are neuron specific proteins that are used in histological studies of brain structure in a variety of vertebrate taxa.Antibodies against NeuN (anti-NeuN) bind to the Fox-3 protein, an RNA binding protein common in mature neurons. Anti-DCX labels a microtubule-associated protein expressed in actively dividing neural progenitor cells and migrating neurons. The DCX gene encodes a protein that is well conserved across mammalian, avian, and a few reptilian species, therefore anti-DCX staining has been used successfully across a range of vertebrate taxa. Successful neuronal staining using anti-NeuN has been demonstrated in mammals, birds, and the …

Evaluation Of Host Resistance And The Utilization Of Organic Amendments To Manage Macrophomina Crown Rot Of Strawberry In California, Jonathan W. Winslow

Master's Theses

The production of strawberries can be severely limited by soilborne plant pathogens, insects and weeds. Macrophomina phaseolina is a problematic soilborne fungal pathogen in California strawberry production inciting the disease Macrophomina crown rot. When established, the pathogen can cause extensive plant decline and mortality. Host resistance will be a critical tool for managing this disease and guiding breeding programs in the post methyl bromide era. Evaluation of host resistance in strawberry germplasm to M. phaseolina was evaluated through phenotypic assessments of disease incidence. A total of 90 strawberry cultivars and elite selections were included in a replicated field trial conducted …

The Effects Of Agricultural Waste-Based Compost Amendments In Organic Pest Management, Gregg T. Stephenson

Master's Theses

Soil-borne pests and pathogens, such as Verticillium dahliae, can devastate a wide range of annual and perennial crops. Current management options for organic production are limited and sustainable management of pathogens, weeds, and arthropods is important for staying profitable and reducing the use of harmful chemicals. Organic soil amendments play an important role in supplying some of the nutritional needs of vegetable crops and improving soil structure, while also contributing to pest control. The objective of this research was to determine the effects of grape and olive-based composts on soil pathogen load, arthropod communities, and weed biomass and diversity. …

Strawberries And Gut Health In Postmenopausal Women, Morgan T. Macneill

Master's Theses

The gut microbiota has been implicated in both health and disease. As such, diet is a significant determinant of gut health, whereby diet induced dysbiosis is associated with cardiometabolic risk. Interestingly, a higher proportion of Firmicutes and a lower proportion of Bacteroidetes are implicated in obesity. Strawberry polyphenols have been shown to reduce cardiovascular disease risk in addition to exhibiting prebiotic activity by increasing probiotic bacteria in the gut. Polyphenols have also been shown to reduce the ratio of Firmicutes to Bacteroidetes. Therefore, dietary modifications such as strawberry consumption may help improve health outcomes through the gut. The objective of …

Effects Of Barotrauma On Four Species Of Pacific Rockfishes (Sebastes Spp.), Lesley Salter

Master's Theses

Physoclistic fish, such as Pacific rockfishes (genus Sebastes), have closed swim bladders that help them regulate their buoyancy. When anglers catch these fish and reel them to the surface, gases within their swim bladder expand due to the decrease in pressure. This can cause their swim bladder to over inflate––a condition known as barotrauma. Overly buoyant fish experiencing barotrauma often struggle to swim back to dwelling depth if released at the ocean’s surface. These fish may experience high rates of mortality by thermal shock caused by the warmer surface temperatures, starvation, predation, or vision problems caused by barotrauma. Assisted …

Study Of Paper Microbial Fuel Cells For Use In On-Site Wastewater Testing, William A. Tolmasoff

Master's Theses

This study demonstrated a technique for fabricating simple, low-cost Paper Microbial fuel cells (PMFC’s) in the model of a previous study to, for the first time, produce voltage from wastewater effluent. The PMFC’s were created by stacking and gluing the main components of an MFC together: reservoir layer; anode; cation exchange membrane (CEM); air cathode. A wax printer was used to create the hydrophobic borders of the PMFC’s on filter paper, and graphite paint was applied to the paper to create the anode. The CEM’s considered were filter paper, wax, and Nafion, with Nafion being the most efficient. Finally, the …

The Development Of Diving Capabilities In Weddell Seal (Leptonychotes Weddellii) Pups Throughout Early Ontogeny, Emma Weitzner

Master's Theses

Weddell seals (Leptonychotes weddellii) are among the deepest diving pinnipeds (i.e., seals, sea lions, and walrus) and one of the best studied marine mammals in the world; as such, these seals are considered a model species for the study of diving physiology and behavior. Adult Weddell seal dive physiology is rather comprehensively understood, yet previous research has excluded an examination of pups’ initial independent diving attempts, beginning instead with the diving capabilities of near-weaning individuals at four to five weeks of age. This is beyond the point many pups have attempted their first independent dives; pups begin to …

Carbonate Chemistry Characterization In A Low-Inflow Estuary With Recent Seagrass Loss, Jolie Higgins

Master's Theses

Estuaries are dynamic environments that are strongly affected by natural variability, as well as direct and indirect anthropogenic impacts. A better understanding of the drivers of carbon fluxes and biogeochemical variability in estuarine systems is needed, particularly with the increasing threat of ocean acidification. Morro Bay in Central California is a small nationally protected estuary, with seasonally low freshwater inputs. Since 2007, the bay has experienced a significant loss of native seagrass, Zostera marina, which is an important component of the marine ecosystem. Because seagrass photosynthesis decreases carbon dioxide and increases oxygen in the water column, the loss of seagrass …

Saponin Removal From Quinoa By Abrasion Processing, Luke Lundberg

Master's Theses

Quinoa is coated with a thin layer of saponins, glycosylated triterpenoids, that produce a bitter flavor when consumed. The average saponin content in commercial varietals from Bolivia average around 2.7% saponins and organoleptic testing shows the threshold for noticing a bitter flavor is below 0.12% (Medina-Meza et al., 2016). Current industrial processing methods use a combination of abrasion and turbulent water flow to remove saponin. This study will address the following research question: How will grain-to-grain and grain-to-surface abrasion affect the processing time to remove saponin from quinoa? In particular, can effective saponin removal be achieved in less than 10 …

Development Of A Pediatric Model Of Nafld In Neonatal Iberian Pigs, Gabriella Veronica Hernandez, Victoria Alice Smith, Morgan Coffin, Daniel Columbus, Matthew Burd, Kimberly Sprayberry, Mark Edwards, Daniel Peterson, Darin Bennett, Robert Fanter, Christopher Kitts, Michael La Frano, Margaret Rice, Douglas Burrin, Magdalena Maj, Rodrigo Manjarin

Master's Theses

The prevalence of non-alcoholic fatty liver disease (NAFLD) in children has increased over the past decades, creating a need for animal models that recapitulate the features of the pediatric disease. Iberian pigs have a leptin-resistant phenotype characterized by hyperleptinemia, hyperphagia, and extreme adipogenesis. We hypothesized that neonatal Iberian pigs fed a high fat high-fructose (HFF) diet will develop a pattern of liver injury resembling pediatric NAFLD. In addition, we sought to determine if a mixture of probiotics would prevent the disease. Animals were fed 1 of 4 diets containing (g/kg body weight × d) 0 g fructose, 11 g fat …

Modifying Succession: A History Of Vegetation Alliances On Swanton Pacific Ranch, Jill Wilson O'Connor

Master's Theses

This thesis conducts historical research into Swanton Pacific Ranch in the County of Santa Cruz, an interdisciplinary facility for education and research managed by Cal Poly’s College of Agriculture, Food and Environmental Sciences. The study seeks to determine whether there have been discernable changes in vegetation alliances (communities), spatially or in type, within a 110-acre Study Area from the early twentieth century to the present day and how the changes compare with other similar historical analyses in California. Historical farming and ranching uses of the area are researched, and two family case studies are presented as paradigms of potential changes …

The Effects Of Providing Social And Nutritional Enrichment To Dairy Calves On Development, Behavior And Learning, Kendra Leigh Kutina

Master's Theses

The objective of this study was to measure the effects of both a nutritional (water nipple) and social (partner calf) enrichment on calf body weight, grain intake, water intake, behavior and learning. The enrichments included 1) water provided from a nipple vs. a bucket (nutritional) and 2) visual and tactile access to a partner vs. isolated rearing with no visual or tactile access to a partner calf (social). A total of 72 Holstein and Jersey dairy calves were pseudo-randomly distributed into 4 treatments at birth [Individual/Bucket (IB), Paired/Bucket (PB), Individual/Nipple (IN), Paired/Nipple (PN)]. Socially and nutritionally enriched calves drank more …

The Proteomic Response Of Northern Elephant Seal (Mirounga Angustirostris) Pups To Physiological Stress During Development, Melissa P. Voisinet

Master's Theses

Background: Northern elephant seals transition from terrestrial nursing pups to pelagic foraging juveniles in a short period of just 8-12 weeks. During the post-weaning period, pups rely solely on the energy reserves gained during nursing for their caloric demands and water supply. The prolonged absence of food after weaning is the first of many fasts for which the seals have evolved adaptations such as decreased urine production and increased blubber reserves. The stressors experienced from learning to dive for the first time are also stressors that they will experience frequently as an adult and for which they have evolved adaptations. …

Comparative Thermal Ecology Of Coastal And Inland Pacific Rattlesnakes (Crotalus Oreganus), Hayley Layne Crowell

Master's Theses

Global biodiversity is declining as a direct result of anthropogenic climate change. Ectothermic species have become focal organisms for studying the ecological effects of altered climates due to the clear relationship between environmental temperatures and ectotherms’ basic physiological functions. Historically, examinations of these effects have focused heavily on heliothermic lizards, and most others have tended to focus on single populations or sympatric species within a single community. Addressing the longterm energetic implications of environmental temperature variation will provide valuable insight into the cascading physiological effects that certain populations or species may experience as a result of altered climates.

In this …

The Effect Of Alcohol And Bitterness Levels On Brewing Yeast Viability, Nichole Elizabeth Bryant

Master's Theses

Two of the most popular beer styles within the craft brewing industry are India Pale Ales (IPA’s) and those with high alcohol by volume (ABV). Production of these styles requires high gravity fermentation and high amounts of bittering hops in order to reach the required values for ABV and International Bitterness units (IBU) respectively. The aim of this study was to determine the impact of high gravity fermentation and high IBU levels on yeast viability and repitching cycles.

An initial experiment on high gravity fermentations was done in order to assess the effects this variable had alone. Successive five day …