Digital Commons Network^™

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 …

A 3-Dimensional In Silico Test Bed For Radiofrequency Ablation Catheter Design Evaluation And Optimization, Carolyn Teng

Master's Theses

Atrial fibrillation (AF) is the disordered activation of the atrial myocardium, which is a major cause of stroke. Currently, the most effective, minimally traumatic treatment for AF is percutaneous catheter ablation to isolate arrhythmogenic areas from the rest of the atrium. The standard in vitro evaluation of ablation catheters through lesion studies is a resource intensive effort due to tissue variability and visual measurement methods, necessitating large sample sizes and multiple prototype builds. A computational test bed for ablation catheter evaluation was built in SolidWorks® using the morphology and dimensions of the left atrium adjacent structures. From this geometry, the …

New England Slave Trader: The Case Of Charles Tyng, Paul J. Michaels

Master's Theses

Charles Tyng has been heralded as an American hero after the posthumous publication of his memoir, Before the Wind: The Memoir of an American Sea Captain, 1808-1833, in 1999. Recent research involving British Treasury report books from the nineteenth century suggest otherwise – that Tyng actively promoted and was engaged in the illicit trade of African captives. A Boston Brahmin, Tyng applied the lessons of his time at sea with Perkins & Company, the opium trading firm, to his occupation as an agent of notorious slave trading firms in Havana. This paper uses as evidence records of the captures …

Evaluation Of Human Umbilical Vein Endothelial Cells In Blood Vessel Mimics Through Changes In Gene Expression And Caspase Activity, Conor Charles Hedigan

Master's Theses

Blood vessel mimics (BVMs) are simple tissue engineered blood vessel constructs intended for preclinical testing of vascular devices. This thesis developed and implemented methods to characterize two of these components. The first aim of this thesis investigated the effect of cell culture duration and flow conditions on endothelial cell gene expression, especially regarding endothelial-to-mesenchymal transition (EndMT). A trend of decreased endothelial marker gene expression and increased mesenchymal marker gene expression would indicate EndMT. qPCR analysis revealed that increased cell culture duration did not result in EndMT, and in fact increased endothelial marker expression as cell culture duration increased. Disturbed flow …

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 …

Observations Of The Copenhagen Networks Study, Michael A. Cantrell

Master's Theses

Attribute-rich longitudinal datasets of any kind are extremely rare. In 2012 and 2013, the SensibleDTU project created such a dataset using approximately 1,000 university students. Since then, a large number of studies have been performed using this dataset to ask various questions about social dynamics. This thesis delves into this dataset in an effort to explore previously unanswered questions. First, we define and identify social encounters in order to ask questions about face-to-face interaction networks. Next, we isolate students who send and receive disproportionately high numbers of phone calls and text messages to see how these groups compare to the …

Dynamic Response Validation Of Cubesats Through Testing And Finite Element Analysis, Peter Rivera

Master's Theses

During a rocket launch, satellites withstand large dynamic forces due to vibrations that are transmitted from the launch vehicle. As such, they must undergo testing to ensure that their function is not impaired by such forces. CubeSats are cost-effective nanosatellites, and like their larger counterparts, undergo dynamic testing for launch qualification. While dynamic analysis can done on a CubeSat alone, other assembly constituents also affect the response, and including them in the analysis can provide insight on the true dynamic behavior of CubeSats. To show this, the work presented here recreates a vibration test setup using Finite Element Analysis (FEA) …

Fracture Control Modeling With The Finite Element Method, Jorge A. Pluma Reyes

Master's Theses

This thesis investigates the feasibility and usability of the finite element method approach in the design of crack arresting devices. Current design and manufacturing practices are improving structures' susceptibility to fracture, in particular brittle fracture; however, cracks in structures are still observed within their lifespans due to severe unexpected service conditions, poor designs, or faulty manufacturing. Crack arrester systems can be added during service to prolong the longevity of structures with sub-critical or critical flaws. Fracture properties of different specific structures under specific services can be obtained experimentally, however, experiments are expensive and of high complexity. Alternatively, the finite element …

Development Of A Model And Imbalance Detection System For The Cal Poly Wind Turbine, Ryan Miki Takatsuka

Master's Theses

This thesis develops a model of the Cal Poly Wind Turbine that is used to determine if there is an imbalance in the turbine rotor. A theoretical model is derived to estimate the expected vibrations when there is an imbalance in the rotor. Vibration and acceleration data are collected from the turbine tower during operation to confirm the model is useful and accurate for determining imbalances in the turbine.

Digital signal processing techniques for analyzing the vibration data are explored and tested with simulation data. This includes frequency shifts, lock-in amplifiers, phase-locked loops, discrete Fourier transforms, and decimation filters. The …

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 …

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 …

Snoring: A Noise Defect Prediction Datasets, Aalok Ahluwalia

Master's Theses

Defect prediction aims at identifying software artifacts that are likely to exhibit a defect. The main purpose of defect prediction is to reduce the cost of testing and code review, by letting developers focus on specific artifacts. Several researchers have worked on improving the accuracy of defect estimation models using techniques such as tuning, re-balancing, or feature selection. Ultimately, the reliability of a prediction model depends on the quality of the dataset. Therefore effort has been spent in identifying sources of noise in the datasets, and how to deal with them, including defect misclassification and defect origin. A key component …

Inventory Of Aging-Friendly Pedestrian Environment, Qijun Zeng

Master's Theses

The dimension of humanization has been neglected for decades. Planning themes such as automobile and transportation have erroneously occupied a dominant position. While public space, pedestrian activities and urban space as a gathering place for urban residents have been placed in a very minor position. As motorization in contemporary cities develops, the overall pedestrian environment of cities is deteriorating, and the street spaces are seriously lacking in the care and consideration of pedestrians, especially the vulnerable groups. Urban design generally, and pedestrian environment in particular, has a significant influence on pedestrian activity. Also, with the aging of the Baby Boomer …

Transmission Probability Of Embolic Debris Through The Aortic Arch And Daughter Vessels During A Transcatheter Aortic Valve Replacement Procedure, Jessica Lena Wirth

Master's Theses

Cerebral ischemia leading to an ischemic stroke is a possible complication of a transcatheter aortic valve replacement (TAVR) procedure. This is because embolic debris can become dislodged and travel through the aortic arch, where they either continue to the descending aorta and join the systemic circulation or travel into the cerebral vasculature through the three daughter vessels that branch off the top of the aortic arch. These three vessels are the brachiocephalic artery, the left subclavian artery, and the left common carotid artery. These three vessels lead either directly or indirectly to the cerebral vasculature, where the diameter of vessels …

Sidewalks To Nowhere: A Tool To Prioritize Pedestrian Improvements, Ho Yan Lai

Master's Theses

Walkability as a concept that captures the ability to walk from one place to another has multiple dimensions. Between traversability to being a proxy for better urban places, there are also numerous measurements of walkability that attempts to quantify certain or all aspects of walkability. It is, however, unclear, through a review of available literature, how these measurements of walkability relate to each other statistically. This methodology focuses on generating a framework for analysts to evaluate and prioritize pedestrian infrastructure. WalkScore™ (WS), HCM Pedestrian Level of Service (PLOS), Average Nodal Degree (AND), and Intersection Density are the four metrics selected …

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. …

In-Plane Cyclic Behavior Of A Steel Mesh Reinforced Cob Wall, Julia Fremuth Sargent

Master's Theses

This thesis presents the results from in-plane cyclic testing of a reinforced cob wall. Cob is an earthen building material composed of sand, clay, straw and water. Cob is typically constructed with no steel reinforcement; however, the California Building Code requires reinforcement in all buildings for resisting seismic forces. The purpose of this thesis is to provide additional technical data to integrate cob into the building code.

Test results are reported for a 7’ x 8’ x 14” wall with two layers of welded wire steel reinforcement constructed on a reinforced concrete foundation. In-plane cyclic loading was performed on the …

Compact Rake Boundary Layer Data System Module, Nathan Jeffry Hoyt

Master's Theses

This Thesis describes the design, assembly, programming, and evaluation of the BLDS-M-RAKE, the newest addition to the family of devices called the Boundary Layer Data System (BLDS). The BLDS-M-RAKE is a continuation of the BLDS-M series of devices, a modular approach with updated electronics for boundary layer measurements. The BLDS-M-RAKE records data from a number of sensors, intended to be routed to an array of probes, or rake. Through preliminary testing, a new flexible manifold design from molded silicone and the hardware used on the RFduino development boards from the BLDS-M proof-of-concept modules were validated for use in the final …

A Paper-Based Elisa Device For The Rapid Detection Of Ischemic Stroke, Andrea Elisabeth Larsen

Master's Theses

Diagnosing an ischemic stroke quickly and accurately is essential for appropriate treatment and results in more effective management of the stroke, leading to better patient outcomes. Specifically, the determination of ischemic versus hemorrhagic stroke leads to critically different treatment paths, which would be potentially fatal if administered incorrectly. Currently, ischemic strokes are diagnosed through a series of tests, including a physical examination, CT scans, and a panel of blood tests to exclude hemorrhagic stroke or other similarly presenting conditions, in order to administer tPA (the main treatment) within the three hour window.

The discovery of biomarkers, molecules which are upregulated …

Evaluating Creative Choice In K-12 Computer Science Curriculum, Kirsten L. Mork

Master's Theses

Computer Science is an increasingly important topic in K-12 education. Ever since the "computing crisis" of the early 2000s, where enrollment in CS dropped by over half in a five year span, increasing research has gone into improving and broadening enrollment in CS courses. Research shows the importance of introducing CS at a young age and the need for more exposure for younger children and young adults alike in order to work towards equity in the field. While there are many reasons for disinterest in CS courses, studies found one reason young adults do not want to study CS is …

Cmos Design Of An 8-Bit 1ms/S Successive Approximation Register Adc, Ameya Vivekanand Ganguli

Master's Theses

Rapid evolution of integrated circuit technologies has paved a way to develop smaller and energy efficient biomedical devices which has put stringent requirements on data acquisition systems. These implantable devices are compact and have a very small footprint. Once implanted these devices need to rely on non-rechargeable batteries to sustain a life span of up to 10 years. Analog-to-digital converters (ADCs) are key components in these power limited systems. Therefore, development of ADCs with medium resolution (8-10 bits) and sampling rate (1 MHz) have been of great importance.

This thesis presents an 8-bit successive approximation register (SAR) ADC incorporating an …

The Investigation Of Methylidyne Radical (Ch) Reactions With Furan, 2-Methylfuran, And 2,5-Dimethlyfuran And The Photoionization And Photodissociation Of Valeric Acid, Erica Carrasco

Master's Theses

This thesis presents the combustion study of three furanic compounds using synchrotron radiation coupled with multiplexed photoionization mass spectrometry at 298 K. The experiments were performed at the Chemical Dynamics Beamline 9.0.2 at the Advanced Light Source of the Lawrence Berkeley National Laboratory. The reactions of the three furanic compounds with methylidyne (CH) radicals were analyzed based on their photoionization spectra and kinetic profiles.

Additionally, the unimolecular dissociation of valeric acid was also studied and presented in this work using the double imaging photoelectron photoion spectrometry (i2PEPICO) coupled with synchrotron radiation from the VUV beamline. The experiments were carried out …

Synchrotron Photoionization Study Of 2,5-Dimethylfuran Oxidation Initiated By O(3p) Atoms, And Computational Studies Of Superalkali Species: Li3f2, Heejune Park

Master's Theses

This thesis presents the experimental study of a 2,5-dimethylfuran oxidation reaction initiated by atomic oxygen (O(³P)) and the theoretical investigation of superalkalis properties. The experiments were performed at the Chemical Dynamics Beamline 9.0.2 of the Advanced Light Source (ALS) located at the Lawrence Berkeley National Laboratory in Berkeley, CA. The first chapter discusses world energy consumption and progress towards new sustainable energy sources, mainly focusing on biofuels, along with a basic description of combustion. A description of the superalkalis and a brief history of synchrotron radiation are also presented in Chapter 1. Chapter 2 describes the components of …

Murder And Machismo: Behind The Motivations Of Salvadoran Women Asylum Seekers, Victoria Colbert

Master's Theses

This thesis aims to draw connections between a culture of machismo, an ideological gender belief distinct to Latin America with heavy traces of patriarchy and misogyny, and the motivations of Salvadoran women seeking asylum in the United States. I develop these connections by first reviewing the literature on structural violence, the form of violence wherein the structure or social institution prevents certain demographics of people from meeting their basic needs and living their optimal lives (Galtung, 1969). I repeatedly use structural violence and its functions to parallel the operations of patriarchy and machismo to suggest that violence against women (VAW) …

Competition And Cooperation In Polygynous & Monogamous Households: Experimental Evidence From Sierra Leone, Bethany Gerdemann

Master's Theses

Competition and cooperation in polygynous households have both been widely documented across various disciplines. There is contradictory evidence as to whether these interpersonal dynamics produce better or worse outcomes for the household. This study uses a competitiveness game and a series of dictator games to measure competition and cooperation within households and between marriage types. Results show that there are key differences between monogamy and polygyny. Monogamous women compete less with their husbands than stranger and less in comparison to polygynous women. Monogamous spouses are more likely to forgo economic opportunities than polygynous spouses and have a greater preference for …

Investigating The Rapid Curing Possibility Of Geopolymer Concrete, Ashlesh Banjara

Master's Theses

Recent studies of heat-cured fly ash based green geopolymer concrete have shown its suitability for fabrication of structural members. Fabrication of these structural members requires continuous moderate heating (145°F) for 24 hrs, and an oven essential, for a large member can quickly turn into an energy guzzler, potentially eliminating the green credentials of the product. The proposed research involves the development of a frontal polymerization (FP) method that achieves rapid curing of geopolymer at ambient condition after short-term heat application. Initial work shows thermal FP in geopolymer is a possibility and might be a solution to the problem. The process …

Development Of A Prototype System For Distributed Spectrum Sensing Via Wireless Sensor Networks, Christopher R. Barber

Master's Theses

This thesis describes the research and development results of designing a system that can detect an unknown transmitter that is operating within a wideband spectrum covering 240-960MHz. The system design, development, and integration of a Prototype Spectrum Sensing Platform for the MEMSIC IRIS wireless sensor network platform [1] can be used for detection, monitoring, and localization of emitters in diverse RF propagation environments. Decoupling the dependency of the Received Signal Strength (RSS) measurements from the primary transceiver by the addition of a secondary receiver provides for continuous real-time analysis of the RF environment signal levels. The goal is to provide …

Effects Of Leaf Litter On Amphibian Site Selection, Rebekah Magee

Master's Theses

Leaf litter plays an important role in the forest ecosystem, impacting various processes and hindering erosion. While there is variability in the chemical and nutritional properties of leaf litter, the effects these variables have on organisms within the environment are not well known. In this study, we examined the effects of leaf litter chemistry on amphibian oviposition site selection. Artificial ponds were created using small, plastic pools, and leaf litter of 15 different tree species (including two invasive species) was added. During the 60 day experiment, water quality measurements (including temperature, pH, dissolved oxygen, conductivity, and water depth) were taken …

Seizure Detection Using Teager-Kaiser Energy And A Channel Signal Quality Assessment Algorithm, Samuel Clary

Master's Theses

This study investigated the possibility of reducing the time required for accurate epileptic seizure detection through a retroactive analysis. Epilepsy is a neurological disorder affecting over 50 million individuals globally and is defined as a disorder which results in two seizures unprovoked by fever or medication. Diagnosis of epilepsy typically involves a monitored stay at an Epilepsy Monitoring Unit (EMU). The monitoring and diagnosis process ranges on average from $35,000 to $40,000 for a single stay, and the patient results from EMU are not instantly available to the patient. The collected electroencephalogram (EEG) must be analyzed by a trained EMU …

Physical Layer Security For Mimo Wireless Systems, Joseph R. Childress

Master's Theses

A steadily growing portion of modern communication systems in use today is based on wireless technologies that make use of smaller and more portable electronic devices. As a result, the need to provide a light-weight security strategy for these systems is becoming a more important problem. This thesis focuses on two techniques that belong to an active research area known as Physical Layer Security (PLS). While the underlying techniques of PLS have been known for some time, the potential secrecy benefits of them need further investigation. These potential benefits have generated a rising interest with the development of Multiple Input …