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Cirrus Microphysical Properties And The Controlling Factors Using A Machine Learning Approach, Derek D. Ngo

Master's Theses

Cirrus clouds are located at high altitudes and are composed of ice crystals. The unique location of cirrus clouds and their large variability in-cloud microphysical properties allow them to have either warming or cooling effects on Earth’s surface and affect the Earth’s energy budget on a global scale. The examination of cirrus radiative effects is further complicated by multiple factors affecting their formation and evolution, including the effects of thermodynamic, dynamic, aerosol, and chemical tracer variables. In this work, we developed a composite aircraft-based in-situ observation dataset based on seven National Science Foundation (NSF) and five NASA flight campaigns that …

Murine Tbk1 Is Required By Flt3+ Leukemia Stem Cells Yet Dispensable In Homeostatic Hematopoiesis, Austin Runde

Master's Theses

The TANK-binding kinase 1 (TBK1) is a cytoplasmic, serine/threonine kinase and a critical activator of the innate immune system. Reports have implicated TBK1 as a promoter of multiple cancer types. Acute myeloid leukemia (AML) is a cancer arising from the hematopoietic stem/progenitor cells (HSPCs). Although ~70% of AML patients achieve complete remission with chemotherapy, at least half will relapse due to the failure to eradicate leukemia stem cells (LSCs). As our previous data indicate the TLR-TAK1/TICAM-1 axes regulate LSCs, we suspect TBK1 also regulates LSCs. To study TBK1 in AML, we generated tamoxifen-inducible, Tbk1-knockout (Tbk1NULL) mice and Tbk1NULL MLL-AF9+ mouse …

Characterizing The Developmental Role Of Autism-Risk Gene Adnp In A Zebrafish Model For Autism, Vaishnavi Balaji

Master's Theses

Autism spectrum disorder is a complex neurodevelopmental disorder characterized by impaired social

skills, restricted/ repetitive behaviors, and developmental delay. The disease has a genetic component,

and mutations in the adnp gene have been found in 0.17% of non-inherited genetic cases of the disorder. The exact molecular mechanism by which adnp is involved in the development of autism is not known. This study aimed to use zebrafish to determine the phenotypic effects of adnp mutations using two adnp paralogs- adnpA and adnpB to understand the underlying mechanism. Novel zygotic adnp double heterozygous mutants (A+/- B+/-) were previously generated using …

Hide And Seek: An Exploration Of Antipredator And Predator Avoidance Mechanisms In Orthopodomyia Signifera In Response To Predation From Toxorhynchites Rutilus, Nathaniel Dahlberg

Master's Theses

There have been many observations of larval Orthopodomyia signifera coexisting with the predator Toxorhynchites rutilus. There are three hypotheses that could explain how Or. signifera resists predation from Tx. rutilus. The first hypothesis states that larvae adapt behavioral changes that limit predation. The second hypothesis states thoracic setae serve as a physical defense that prevents Tx. rutilus from grasping Or. signifera. The third hypothesis states Or. signifera possess a chemical defense indicated by aposematic coloration. To test the first hypothesis larval Or. signifera were exposed to conspecific and heterospecific predation cues and their behavior was observed. Both cues …

Disability Identity In Samuel Taylor Coleridge's Letters, Jackson Fields

Master's Theses

This thesis focuses on letters written by British Romantic author Samuel Taylor Coleridge, who wrote about his chronic illness during the period of emerging modern ideas of disability. Coleridge’s letters are valuable to readers in the twenty-first century because they enable us to track the formation and negotiation of Coleridge’s disability identity. As one of the most important thinkers and authors in the English language, Coleridge has a lot to teach us about how one can understand their illnesses, medical authority, and the influences of disability on friendships and social roles. This thesis considers Coleridge’s letters to his loved ones …

Barn Owls (Tyto Alba) And Biodiversity Near Hemp Farms And Grasslands In Oregon, Usa, Lacey Brianne Thun

Master's Theses

Extensive agriculture poses a major threat to biodiversity worldwide, although some species, such as the barn owl (Tyto alba), can thrive in many agroecosystems. Barn owls, the world's most widely distributed owl, provide rodent management, and their presence may be both an indicator of and support for ecosystem biodiversity. Little previous research documents the relationship between barn owls and adjacent crop attributes, however. In 2018, hemp (Cannabis sativa) was taken off the federal Controlled Substance Act list and permitted as an agricultural crop. Hemp is now rapidly increasing in extent in Oregon, USA. This research assessed the reproductive success and …

No Kidding: The Moderating Role Of Childcare Responsibility On The Relationship Between Perceived Work-Life Balance Policy Culture And Job Outcomes, Ziwei Gao

Master's Theses

The societal assumption that everyone will or should have children at some point is deeply ingrained in many cultures. This often results in a lack of recognition and understanding of the experiences of childfree individuals, particularly within professional settings. Therefore, the present study aimed to examine the moderating effect of childcare responsibility on the relationship between perceived work-life balance policy culture and job outcomes. A sample of 161 participants completed an online survey measuring perceived work-life balance policy culture, job satisfaction, organizational commitment, and turnover intentions. Results showed that employees with high levels of perceived work-life balance policy culture reported …

Tree Removal From An Encroached Coastal Grassland Restores Soil Bacterial Communities Before Fungal Communities, Ka Ki Law

Master's Theses

Woody species encroachment depletes historic grassland biodiversity and degrades ecosystem function around the world. In particular, the encroaching trees can shift soil properties and microbial communities, which play critical roles in plant health and global nutrient cycling. Little is known about how removing encroached trees affects soil ecosystems, however. Over the last century, Pinus radiata and Hesperocyparis macrocarpa (non-native to the area) both encroached into coastal prairies at Rancho Corral de Tierra in California, and selected trees were removed in 2017 and 2018 to restore grassland habitats. To examine the impacts of encroachment and removal on the soil ecosystem, I …

Effects Of Hypoxia On Anti-Predator Behavior Of English Sole (Parophrys Vetulus) And Speckled Sanddabs (Citharichthys Stigmaeus), Alexandra Beatrix Stella

Master's Theses

Predator detection and successful escape behaviors are critical to the survival of juvenile fish. However, rising temperatures and increased nutrient pollution result in more frequent hypoxic events (i.e., low dissolved oxygen levels), which may impact fish health and survival. This research examined the effects of hypoxia on two flatfish species commonly found in the Elkhorn Slough, an important nursery habitat in central California. English sole and speckled sanddabs were exposed to five DO treatments ranging from 8.0 mg/L DO (normoxic) to 1.0 mg/L DO (severely hypoxic). A startle response trial was used to examine the impact of increasingly hypoxic conditions …

Distribution And Habitat Use By Western Burrowing Owls (Athene Cunicularia Hypugaea) In Alameda, Contra Costa And San Joaquin Counties, California, Jacqueline Taylor

Master's Theses

Grasslands are regularly altered for development, agriculture, and animal farming which leads to habitat destruction and fragmentation and, ultimately, a loss of wildlife species. Though degraded, grassland ecosystems – including native and non-native species - dominate the landscape in the region of the San Francisco Bay Area east of the Bay. The western burrowing owl (Athene cuncularia hypugaea) is a native grassland species of California. The breeding burrowing owl population in the San Francisco Bay Area is resident, but burrowing owls from other parts of the range migrate into the region for the winter. The breeding owl populations in the …

Manifestations Of Communicative Resilience In Experiences Of Serial Arguments Among Adult Children Of Harmful Parental Alcohol Use, Brooklyn Willis

Master's Theses

This thesis investigated the ways in which adult children of harmful parental alcohol use manifest resilience through the lens of the Communication Theory of Resilience (CTR). The CTR presents five communication processes by which resilience, which is the ability to overcome hardship, is demonstrated. Serial arguments, the repeated and unresolved conflicts that occur between romantic partners, were utilized as the context to study resilience. Interviews were conducted to learn about perceptions of serial argument resolvability and the ways and frequencies in which resilience manifested. A pre-interview survey gathered information pertaining to relationship satisfaction and perceptions of resilience. A thematic analysis …

The Correlation Between Perceived Maternal Parenting Style And Perceived Emotion Regulation In Seventh-Day Adventists In Southern Brazil, Camila Cardoso Masotti

Master's Theses

Problem.\

One's ability to regulate his/her emotions utilizing coping mechanisms and dissuasive mental strategies is partly attained due to the correct functioning of innate biological systems and to life experiences that promote learning/training in this area (cf., e.g., Matsumoto & Hwang, 2012). The field of emotion regulation studies has extensively elaborated on a multivalent description of human emotional development, in which emotions are part of essential mental strategies for an individual's conscious and unconscious goals in life (cf., e.g., Lang & Bradley, 2010; Levenson, 1999). Therefore, as a partly learned ability, one's emotion regulation skills have been shown as positively …

A Population Level Examination Of The Incredible Fruit Diversity In Astragalus Lentiginosus, Quinn Thomas

Master's Theses

Astragalus lentiginosus is the most taxomically diverse species in the North American flora with over 40 recognized varieties. The incredible diversity within A. lentiginosus, particularly in respect to its fruit morphology, makes it an exceptional model to study adaptation and evolution. However, it remains unknown whether fruit morphology is an adaptation and, if so, the extent to which selection or neutral evolutionary processes shape the striking diversity in this trait. In order to understand the adaptive significance of fruit morphology we must first understand the genetic structure of A. lentiginosus. Varieties of A. lentiginosus vary considerably in their range size …

Influence Of Prescribed Burning On Coast Redwood (Sequoia Sempervirens) Forest Wildfire Resistance, Resilience, And Risk Of Repeated Fire, Sky B. Biblin

Master's Theses

Land managers need tools to mitigate wildfire proliferation in the western United States. Prescribed burning may be an effective tool to reduce wildfire severity and promote healthy landscapes. In 2020, a large-scale wildfire provided a rare opportunity to compare early postfire data between areas with and without a history of prescribed burning. Field data were collected approximately one year after a wildfire in fifty 20-meter plots from sites treated with prescribed fire in either 1999, 2007, or 2011 and fifty from sites without a history of prescribed fire. The influence of prescribed burning on forest resistance, resilience, and risk of …

Western Snowy Plover Dispersal In Response To Repeated Nest Loss In Monterey Bay, California, Esther A. Haile

Master's Theses

Western snowy plovers (Charadrius nivosus nivosus) breed and winter along sandy beaches and salt pannes of the Pacific coast of the U.S. and Mexico. Since 2015, the percentage of successful nests in Monterey Bay has declined due to predation. This study examines the site fidelity and dispersal of western snowy plovers after repeated nest loss using nesting data from 2013-2020 from a banded population in Monterey, California. Dispersal distance within a breeding season reflected plovers serially polygamous breeding strategy, with more site fidelity within a breeding season than between two breeding seasons. Nests lost to environmental causes having a 41.3% …

Bubble Detection Under Microgravity In A Closed-Loop Microchannel Perfusion System, Max S. Kim

Master's Theses

Altered gravitational conditions result in changes in biological function. Studies in microgravity have shown irregularities in fluid redistribution within the vascular system. In order to study these irregularities, a cell culture perfusion system is necessary. Bubbles can proliferate in closed-loop systems and are detrimental to cells. However, the effects of bubbles in a closed-loop system in microgravity are unknown. Accordingly, the hypothesis of this investigation is that the absence of a constant-direction gravitational body force will exacerbate the presence of bubbles in a closed-loop microfluidic perfusion system. In order to examine the hypothesis, a closed-loop microfluidic cell culture perfusion system …

Combining Camera Trap And Fitness App Data Demonstrates That Mammals Change Behavior Near High-Use Bike Trails On Mount Tamalpais, Ca, Erin Rose Lacour

Master's Theses

Anthropogenic disturbance that results in habitat loss is the leading cause of the current extinction crisis. To mitigate loss of habitat, protected lands are dedicated to preserving ecosystems, but such areas often allow outdoor recreational activities. Research has shown negative impacts on a range of species from outdoor recreational activities, and there is little information about potential impacts of mountain biking on wildlife. Mountain biking and hiking tracking data from the social fitness app Strava Metro and data from a camera trap project in Marin County, CA, were analyzed to assess how mammal species’ spatial distribution, temporal activity, and richness …

Sustainable Roots: The Environmental Genealogies Of Chicanas And Latinas, Marlene Andrade

Master's Theses

Ingenuity and tending to the land are anything but contemporary to Communities of Color (COC). Even when our communities become targets of environmental racism and experience the brunt of institution-based degradation, COC resist in a multitude of ways. While there is a plethora of documented social movements led by the Chicanx community for civil, educational, and labor rights, there is a paucity of Chicanx presence in environmental discourse. Thus, my scholar-activist commitments are to highlight Chicana/Latina herstories, epistemologies, and praxes that debunk the narrow white-heteropatriarchal male narrative in mainstream environmentalism. This dominant narrative fails to: (a) address the historical and …

The Inverse Association Between Prebiotic Consumption And Depression Status In American Adult Females, But Not The Greater Population Or In Males: Nhanes 2015-2018, Cassandra L. Boyd

Master's Theses

It is unknown if a relationship exists between prebiotic intake and depression status. Using 2015-2018 National Health and Nutrition Examination Survey cycles data, adult American estimated mean daily prebiotic intake across demographic groups, gender, and depression status were reported. Additionally, the 10 highest prebiotic content Food and Nutrient Database for Dietary Studies foods were identified. Adults (≥ 18 years) with adequate sleep and at least one day of dietary recall data were included. Participants with excessive alcohol intake, BMI ≤ 18, BMI ≥ 30, or current depression medication use were excluded. The confounding variables were inadequate sleep, unemployment, and age. …

Thinking Styles, Conspiracist Belief, And The Mediating Role Of The Dunning-Kruger Effect In Modeling Belief Change, Lucas C. Cusano

Master's Theses

Why can a person believe something for which there is no evidence and yet also fail to believe something for which there is overwhelming evidence? This study develops a structural model of belief change using the latent constructs of thinking styles and conspiracist belief while accounting for the Dunning-Kruger effect (i.e., overconfidence in one’s knowledge the less one knows about a topic) as a mediator. A combined two-hundred and twenty-six participants from both Amazon’s Mechanical Turk and the introductory psychology SONA subject pool were given two knowledge measures on topics of genetic modification and vaccination before and after reading refutational …

Examining The Role Of Echo-Chambers Within Online Incel Communities Using Sentiment Analysis And Group Based Trajectory Modeling, Francesca Florine Fanucchi

Master's Theses

Technological advancements within the last decade have created new opportunities for social movements to meet and communicate online with like-minded individuals. Under this notion, these online communities generate an echo-chamber of information, to which certain individuals only surround themselves with people sharing similar values and opinions. As a result, online platforms (e.g., forums, blogs, websites) form as safe spaces for members to express their views seen as unacceptable offline. Research examining the role of echo-chambers in facilitating extremist rhetoric within online incel communities is limited, despite real-world acts of violence perpetrated by self-proclaimed incels. Therefore, the objective of this thesis …

Examining The Plasticity Of The Dive Response In Relation To Dive Behavior Of Northern Elephant Seals (Mirounga Angustirostris), Shawn M. Hannah

Master's Theses

Marine mammals face an extraordinary challenge as they must actively hunt during breath-hold dives. This challenge is conquered by the dive response (the decreased heart rate and increased peripheral vasoconstriction associated with a breath hold) and is influenced by dive duration, depth, exercise, and cognitive control. I studied the dive response of one of the deepest diving marine mammals, the northern elephant seal, across two years to determine interactions between behavioral and physiological factors on a fine scale. I examined the influence of dive depth, duration, and activity (ODBA) on dive heart rate (fH), pre- and post-dive fH, post-dive surface …

Where And Why Do Ecosystem-Based Adaption Projects Take Place In California?, Daniel K. Jacobson

Master's Theses

California is experiencing the harmful impacts of climate change and will continue to do so for generations. As a result, municipalities have been forced to turn to adaptation solutions to help local residents adjust to inevitable impacts such as sea level rise, extreme heat, and extreme weather. Ecosystem-based adaptation (EbA), the use of nature and ecosystem services to help human systems adapt to climate change impacts, is an increasingly popular, cost-effective, and multi-benefit adaptation strategy. While prior research has shown that other forms of adaptation, often referred to as ‘hard’ and ‘soft’ strategies, disproportionately benefit whiter and wealthier populations, there …

Linking Social Dynamics To Private Land Management: A Study Of Prescribed Burn Associations In Northern California, Spencer R. Klinefelter

Master's Theses

Prescribed fire is one way to improve the adaptive capacity of communities in the wildland urban interface in terms of managing wildfire risk and meeting socio-ecological goals. In California, Prescribed Burn Associations (PBAs) are a way of organizing private landowners with the goal of engaging in more widespread and frequent prescribed fires. This research uses semi-structured interviews with private landowners, along with key informants from public agencies such as CalFire and Regional Parks, to explore PBA development and functioning in northern coastal California. Sonoma and Marin counties were chosen as the primary study sites as they are represented by the …

Characterization And Evaluation Of Catalytic Activity Of Small Molecule Copper Complexes For Metallopolymer Design, Brenda Lu

Master's Theses

Catalysis is one of the driving forces in designing greener chemical processes for essential real-world applications. Enzymes, Nature’s catalysts, are known for their high selectivity, use of readily available metals and reagents, and ability to work under physiological conditions; three important qualities that synthetic chemists would like to mimic in their small molecule metal catalysts. Though most small molecule metal catalysts fall short of enzyme-like activity, we hypothesize that using a polymer scaffold as a secondary coordination sphere mimic around the metal complex will affect the microenvironment (steric and electronic) and enable enzyme-like activity. Previously, we synthesized ligand precursors and …

Intrinsic Motivation By The Principles Of Non-Linear Dynamical Systems, Phu C. Nguyen

Master's Theses

The design of appropriate control rules for the stabilization of dynamical systems can require quite substantial domain knowledge. Modern AI methodologies, such as Reinforcement Learning, are often used to mitigate the need for such knowledge. However, these can be slow and often rely on at least some hand-designed reward structure, and thus human input, to be more effective. Here, we propose an alternative route to construct rewards requiring only minimal domain knowledge, essentially relying on the structure of the dynamical system itself. For this, we use truncated Lyapunov exponents as rewards to calculate the stabilizing controller from samples. Concretely, the …

Controllability-Constrained Deep Neural Network Models For Enhanced Control Of Dynamical Systems, Suruchi Sharma

Master's Theses

Control of a dynamical system without the knowledge of dynamics is an important and challenging task. Modern machine learning approaches, such as deep neural networks (DNNs), allow for the estimation of a dynamics model from control inputs and corresponding state observation outputs. Such data-driven models are often utilized for the derivation of model-based controllers. However, in general, there are no guarantees that a model represented by DNNs will be controllable according to the formal control-theoretical meaning of controllability, which is crucial for the design of effective controllers. This often precludes the use of DNN-estimated models in applications, where formal controllability …

Behavorial Response Of Diving Northern Elephant Seals (Mirounga Angustirostris) When Exposed To Predator Calls, Daphne M. Shen

Master's Theses

Understanding how marine mammals respond to and recover from acoustic stressors is crucial if underwater noise increases. The use of an animal-borne biologger that combines a speaker with a motion sensor allows for the collection of whole-dive and fine-scale data over repeated exposures under identical experimental parameters. This study determined whether northern elephant seals (Mirounga angustirostris), a model for deep-diving marine mammals, exhibited a stereotypical behavioral response when exposed to killer whale whistles, an acoustic stressor. I examined changes in dive characteristics, measured duration of altered response, and observed behavior in response to repeated exposures. When exposed to the playback …

Micro-Scale Laser-Induced Fluorescence Thermometry For Multiphase Flow In Porous Media, Samuel J. Simmons

Master's Theses

In this thesis the use of Laser-Induced Fluorescence (LIF) thermometry was evaluated as a temperature measurement for multiphase flow in porous media. This optical temperature measurement technique utilizes the temperature-dependent emissive properties of fluorescent dyes to measure temperature. This research evaluates the accuracy, spatial resolution, and temporal resolution of LIF thermometry compared to existing temperature measurements. In this research water-soluble and oil-soluble fluorescent dyes are evaluated in terms of their temperature sensitivity. The ability of these dyes to measure temperature is compared to an Ansys FEA simulation of a fixed temperature gradient. For multiphase flow, the fluorescent dyes were both …

Development Of Inattention And Executive Dysfunction In Youth With Spina Bifida: Condition Severity Variables As Predictors, Allison D. Payne

Master's Theses

Spina bifida (SB) is associated with neurologic impairments that increase individuals’ risk for neuropsychological deficits, particularly inattention and executive dysfunction. While extant literature has yet to examine the development of inattention in youth with SB, some research suggests that these youth may not experience the age-related improvements in executive dysfunction seen in the general population. SB is a heterogeneous condition; thus, it is important to consider variability in condition severity when examining outcomes over time in youth with SB. Lesion level and shunt status are commonly used as indicators of SB severity and have been significantly associated with variability in …