Digital Commons Network^™

Assessing Structural And Functional Brain Alterations And Work-Related Fatigue In Non-Hyposmic And Hyposmic Covid-19 Survivors, Rakibul Hafiz

Dissertations

In the year 2019, life began to change at the advent of a global pandemic caused by the novel coronavirus. Mask mandates and mass vaccinations have mitigated the effects significantly, yet cases keep rising with new variants, especially, in densely populated countries, like India. Recent neuroimaging evidence shows the virus can attack the central nervous system (CNS). However, exactly which brain regions undergo structural and functional changes remain largely unknown. Many patients experience 'loss of/reduced sense of smell' (i.e., hyposmic) and an alarming number of survivors develop persistent symptoms ('long-COVID') for several months after initial infection. Fatigue is the most …

Repeated Low-Level Blast Induces Chronic Neuroinflammation And Neurobehavioral Changes In Rat Models, Arun Reddy Ravula

Dissertations

Blast-induced neurotrauma (bTBI) is a signature medical concern for military personnel when they are exposed to explosions in active combat zones. However, soldiers as well as law enforcement personnel are also repeatedly exposed to low-level blasts during training sessions with heavy weaponries as part of combat readiness. Service personnel who sustain brain injuries from repeated low-level blasts (rLLBs) do not display overt pathological symptoms immediately but rather develop cognitive impairments, attention deficits, anxiety, and sleep disturbances over time. An improved rat model of rLLB was developed in this thesis by applying controlled low-level blast pressures (10 psi) repeated five times …

Reactive Iron Mineral Coatings In Redox Transition Zones Of A Site With Historical Contamination: Abiotic Attenuation, Xin Yin

Dissertations

Reactive iron mineral coatings are found throughout reduction-oxidation (redox) transition zones and play a significant role in contaminant transformation processes. In this study, an 18.3-meter core is collected, subsampled, and preserved under anoxic conditions to maintain its original redox state. Screening analyses are conducted at sampling increments of 5.08 cm in depth for the following: elemental concentrations with X-ray fluorescence (XRF), sediment pH, sediment oxidation-reduction potential (ORP), total volatile organic carbon (TVOC) in the sample headspace, and abundant bacteria (16S rRNA sequencing). Using the Fe and S gradients correlated with microbial data, five RTZs are delineated. To characterize iron mineral …

Development Of Novel Mass Spectrometric Methods For Reaction Screening, Oligosaccharide Detection, And Nitrosamine Quantitation, Qi Wang

Dissertations

Benefitting from its high detection sensitivity and specificity, mass spectrometry (MS) has become a powerful technique in academia and industry. The aim of this dissertation study is to develop new mass spectrometric methods for organic reaction screening, detection of oligosaccharide/glycan in complex matrices, and nitrosamine absolute quantitation.

First, an electrochemistry/mass spectrometry (EC/MS) platform is built to generate an N-cyclopropylaniline radical cation electrochemically and to monitor its reactivity toward alkenes, which leads to the discovery of a new redox neutral reaction of intermolecular [3 + 2] annulation of N-cyclopropylanilines and alkenes. Net redox neutral electrosynthesis is quite rare in synthetic organic …

Adversarially Robust And Accurate Machine Learning For Image Classification, Yanan Yang

Dissertations

Machine learning techniques in medical imaging systems are accurate, but minor perturbations in the data known as adversarial attacks can fool them. These attacks make the systems vulnerable to fraud and deception, and thus a significant challenge has been posed in practice. This dissertation presents the gradient-free trained sign activation networks to detect and deter adversarial attacks on medical imaging AI (Artificial Intelligence) systems. Experimental results show a higher distortion value is required to attack the proposed model than other state-of-the-art models on brain MRI (Magnetic resonance imaging), Chest X-ray, and histopathology image datasets. Moreover, the proposed models outperform the …

Private Information Retrieval And Function Computation For Noncolluding Coded Databases, Sarah A. Obead

Dissertations

The rapid development of information and communication technologies has motivated many data-centric paradigms such as big data and cloud computing. The resulting paradigmatic shift to cloud/network-centric applications and the accessibility of information over public networking platforms has brought information privacy to the focal point of current research challenges. Motivated by the emerging privacy concerns, the problem of private information retrieval (PIR), a standard problem of information privacy that originated in theoretical computer science, has recently attracted much attention in the information theory and coding communities. The goal of PIR is to allow a user to download a message from a …

The Impact Of Material And Environmental Properties On The Ettringite - Metaettringite Thermochemical Reaction, Aaron Strand

Dissertations

The use of energy is an essential need for people, with demand constantly increasing due to an increasing population and an increase in living and comfort standards. Since 1965, world energy consumption has quadrupled. During peak utilization, the strain on the grid infrastructure can be immense. As energy demand fluctuates during different times of the day and year, the energy production needs to scale accordingly This creates inefficiencies within the system such as over building generation capacity or losses from start up or ramping up production. This can be alleviated through load leveling where excess energy generated during low demand …

Bodipy-Based Light-Responsive Materials, Zhaoxiong Wan

Dissertations

The energy required for life on our planet is provided by light. In science, light is an important and powerful tool for measuring and modifying substances. For example, under the effect of illumination, light-responsive materials can change their physical and chemical properties. Photochemistry is a branch of research to study the effects of light irradiation on chemical structures and reactions. Some photochemical changes could lead to chemical bond dissociation (such as in photosynthesis) and structure isomerization (such as in the retina). Photochemistry has a strong relationship with human lives and it is essential in many ways. Among photophysics, fluorescence emission …

Design Of Self-Assembled Peptides For Wound Healing, Ka-Kyung Kim

Dissertations

According to the CDC, 15% of diabetic patients develop diabetic foot ulcers (DFU) and approximately 170,000 patients undergo non-traumatic amputation annually. DFU is a major complication of diabetes caused by non-healing full-thickness wounds through the dermis. The current treatments include blood sugar control, frequent debridement, offloading, moist wound care, infection treatment, and amputation. To achieve wound closure of DFU, appropriate wound care and antibiotic therapy are essential. Topical regimens include hydrocolloids, alginates, foam, silver-impregnated dressings, and hydrogels. Wound healing is a complex and dynamic interplay between the immune system, keratinocytes, and dermal cells (in case of cutaneous wound). Angiogenesis has …

Experimental And Theoretical Studies Of Flows Driven By Soluto- And Thermo-Capillary Forces, Islam Benouaguef

Dissertations

This dissertation aims to study the flow induced in a water body due to the presence of a solute or heat source on its surface. The flow arises because of a change in the local solute concentration or the temperature, which modify the local surface tension, giving rise to a surface tension gradient that drives the flow. These surface tension-driven flows are referred to as Marangoni flows. The following three induced-flows are investigated experimentally and theoretically: (i) Flow induced by a solute source present on a waterbody; (ii) Flow induced due to the impingement of a freshwater drop on a …

Optimization Of Polyhydroxyalkanoates (Phas) Bioplastic Production From Wastewater Activated Sludge, Bo Deng

Dissertations

Polyhydroxyalkanoate (PHA) is a biopolymer which has similar properties as fossil-fuel based plastic but also has capacity to biodegrade completely in the environment condition. This project aims to optimize the process to produce bioplastic PHA using activated sludge from wastewater. Specifically, five major research objectives are explored: (i) develop a quantification method of PHA by using Fourier-transform infrared spectroscopy (FTIR)F; (ii) improve the PHA production from mixed microbial cultures (MMC) by optimizing MMC; (iii) simulate the PHA production by using wastewater; (iv) evaluate the application of enzyme (alpha-amylase) in PHA production process; (v) market the investigation of wastewater produced PHA. …

A Bioactive Composite Scaffold Containing Zinc For Bone Tissue Engineering, Jennifer W. Moy

Dissertations

Non-union bone fractures occur during 5-10% of all bone fractures where the fracture is incapable of healing despite current surgical interventions with the use of bone grafts and graft substitutes. As an alternative, studies utilize growth factors and other biomolecules to differentiate mesenchymal stem cells into osteoblasts to aid in bone formation in vitro and in vivo studies. Zinc has known insulin-mimetic properties and are incorporated into multiple tissue engineering approaches to aid in osteogenesis, bone formation, and vascularization. In this work, mesenchymal stem cells (MSCs) were evaluated for the effect of zinc on osteogenesis. The supplementation of zinc in …

Constitutive Modeling And Numerical Simulations Related To Dual And Triple Shape Memory Polymers, Aayush Prasad

Dissertations

Shape memory polymers (SMPs) are a class of soft active materials that have the ability to retain one or multiple temporary shapes and exhibit deformation as a response to stimuli. The temporary shapes involved can be very complex, but SMPs can recover large amounts of strains compared to other smart materials. They have a wide range of applications, and their mechanism can be easily altered. Hence, there is an increasing need to model their behavior.

This study discusses the behavior of a thermally activated subclass of SMPs in which the temporary shape is fixed by a crystalline phase and the …

Synthesis Of Polynitrogen With Radio Frequency Plasma, Haizheng Zhuang

Dissertations

Cubic gauche polynitrogen (cgPN) has been very attractive due to its high energy density that is 2.5 times higher than that of TNT. In the literature, cgPN has been investigated theoretically in detail, but few experimental works have been reported. In 2004, cgPN was first synthesized from nitrogen gas under extremely high temperature and high pressure (HTHP) conditions and the trace amount of cgPN in the high-pressure vessel decomposed once the pressure was released. Until recently, our group was the first to synthesize cgPN from NaN₃ precursor under ambient conditions with radio frequency (RF) plasma. In this study, the …

Integration Of Customer Preference To Smart Locker Location Planning For Last Mile Delivery Optimization, Colette Malyack

Dissertations

Understanding customer preference associated with delivery solutions, such as the use of smart lockers, is an area of increasing interest for package delivery companies. Applications of this data could result in cost savings through vehicle route decisions, cross-docking and fleet size optimization, and increased placement of smart locker technology for stop reduction. However, there has been little effort applied to gathering information related to public preference solutions to last mile package delivery. Therefore, preference data is gathered and analyzed related to smart lockers, and apply the results to delivery route and cross-docking optimization through package locker location planning within the …

Factors That Contribute To Lower Enrollments Of Underrepresented Minority And Female Graduate Students In Computer Science And Engineering (Cse) At Bay Area California State University Campuses And Mitigating Factors From Student Perspectives, Noah G. Price

Dissertations

Over the last decade the Bay Area region has witnessed a lack of diversity in Silicon Valley technology professions, a subject of current political and popular discourse. The California State University (CSU) system provides accessible higher education; the CSU system approach to accessible higher education affirms the distinctness of regions, prepares graduates for professions in these distinct regions, and affirms the diversity in the state and the world. The CSU fall 2019 - 2021 enrollment dashboard data indicated there was a decrease in enrollment of underrepresented minority (URM) in graduate programs across three Bay Area campuses. Public fall 20119 - …

Faculty And Administrator Perspectives On Campus Internationalization At Selected California State University And University Of California Campuses: Individual Efforts And Interconnected Roles, Parinaz Zartoshty

Dissertations

This explanatory mixed-method research study explored campus internationalization trends by examining the practices of faculty and administrators engaged in campus internationalization efforts at selected four-year public institutions in Northern California. Most survey respondents and interviewees recognized the importance of internationalization, prompted greatly by their own personal transformational “international” journey, making them identifiable champions who can assist in promoting internationalization efforts. Most maintained that the system and their individual institutions do not provide adequate incentives to those faculty who are not personally motivated to engage in international activities and acknowledged internationalization does not float to the top of priorities. In instances …

Student Engagement And Universal Design For Learning (Udl): A Community College Case Study, Candice R. Nance

Dissertations

Community colleges have a significant impact on education. The community college population includes some of the most vulnerable students who have the most to gain from educational attainment. The objective of this mixed-methods case study was to investigate the practical implications and impact of Universal Design for Learning (UDL) on student learning, engagement, and sense of belonging. Forty-nine students participated in this study from seven sections of an asynchronous introduction to business course at a California community college during the COVID-19 pandemic. Findings suggested that the UDL intervention increased students’ final grade percentages, exam scores, and group project scores while …

The Hustler Award Program, Julia N. Biayi

Dissertations

Problem: Hospitalized adults are at increased risk of falling due to multiple aspects, including but not limited to changes in health status, the environment, pain, weakness, confusion, and prolonged immobility. This project focused on the question: How will the utilization of the Hustler Award Program decrease fall rates in an adult inpatient medical-surgical unit?

Method: A prospective quality improvement pilot study focused on a 24-bed medical-surgical unit in a Midwest, 487-bed metropolitan-based facility.

Results: The results captured are for the evaluation period occurring from September through November 2021. The staff responded to 52-bed exit alarms, which yielded a response rate …

Implementation Of The Bedside Mobility Assessment Tool In The Ambulatory Care Setting, Racquel Hermosura Ballinger

Dissertations

Falls remain a concern for healthcare organizations nationally. Fall rates at the site remained a concern, so an evidence-based approach was sought. The purpose of this quantitative, quasi-experimental quality improvement project was to determine if the implementation of Boynton's Bedside Mobility Assessment Tool (BMAT) used in conjunction with current fall practices would impact fall rates among patients 65 years and older undergoing a colonoscopy. The project was implemented in an ambulatory care setting in Southern California over four weeks. Sister Callista Roy's middle-range nursing theory, the adaptation model, and Neuman's systems theory were the scientific underpinnings of the project. Data …

From Empathy To Social Empathy: A Journey In A Diversity, Equity, And Inclusion Workplace Graduate Certificate, Francesca Ferrari, Lisa M. Woodrum

Dissertations

This study aimed to explore and understand the impact of the Graduate Certificate in Workplace Diversity, Equity, and Inclusion (DEI Graduate Certificate) on master’s and doctoral students’ social empathy (SE) development. The participants in this certificate engaged in several online activities that increased their knowledge of microaggressions, privilege, and unconscious bias while building their social empathy. This certificate provided various tools and skills to its participants so that they might value diversity, look at the world from another’s perspective, and start a dialogue to promote social change. This case study involved 19 participants. To answer our research questions, we used …

The Impact Of Hospital Nursing Resources On Postsurgical Outcomes For Patients With Opioid Use Disorder, Rachel E. French

Dissertations

Opioid use disorder (OUD) is common, with the rate of opioid-related hospitalizations doubling from 2006 to 2016. Surgical patients with OUD are at significantly higher risk of prolonged length of stay, in-hospital mortality, and readmission. Postoperative care for patients with OUD is particularly challenging for nurses whose responsibilities include pain and withdrawal management, care team coordination, patient assessment, and patient teaching. A large body of evidence suggests better outcomes for surgical patients when they are cared for in hospitals with strong nursing resources. This study sought to determine whether variations in nursing resources (i.e., education, staffing, and work environment) were …

Learning To Fly: The Impact Of Project-Based Learning On Development Of The 4cs In The Elementary Grades, Deborah Francois

Dissertations

Purpose: The purpose of this qualitative phenomenological study was to investigate the impact of project-based learning on K-5 students’ development of the 4Cs (Critical Thinking, Communication, Creativity, Collaboration) as perceived by elementary charter school teachers.

Methodology: A phenomenological design was selected to address the research questions for this study. Through purposeful sampling, 12 charter elementary teachers who met a pre-determined set of criteria (including the routine integration of project-based learning within their instructional programs) were selected to participate in virtual, semi-structured interviews. All teachers were employed by charter schools located in six counties within California. The interviews were conducted using …

Understanding Food Waste Behavior And Ways To Influence Positive Change And Waste Reduction, David Hubinger

Dissertations

Environmental problems such as pollution, climate change, and food waste can be influenced by social attitudes and human behavior. Solutions to address environmental problems involve a series of actions by society and individuals, which can prove difficult to implement because changes induced by pro-environmental behavior often cannot be seen immediately by individuals or may not generate appreciable, direct benefits. The purposes of the quantitative correlational study are threefold: first, examine environmental attitudes, subjective norms, perceived behavioral control, and overall behavioral intent to reduce household consumer food waste among a sample of consumers; second, to examine the extent to which select …

Black Beyond Measure: An Antideficit Exploration Of Cultural Capital Within A National Society Of Black Engineers (Nsbe) Chapter At A Predominantly White Institution (Pwi), Rhonda Harley

Dissertations

Historically, Black students have been excluded from Predominately White institutions (PWI) longer than welcomed to attend and matriculate (Harper et al., 2009). Due to this lack of inclusion, African American students' educational experiences often center on academic disparities, inequality of opportunity, and under-preparedness in career planning within the American education system. While there has been a fair amount of research on the lack of representation of Black students in the engineering disciplines, the heavy focus on quantitative data offers little insight into the unique ways students succeed and overcome institutional and systemic barriers in pursuit of their degree. Undergraduate experiences, …

Improving The Retention Of United States (U.S.) Government Science, Technology, Engineering, And Mathematics (Stem) Employees, Jeffrey Myers

Dissertations

The U.S. government workforce has been consistently shrinking since a peak in the 1990s. At the same time, the need for technologically-savvy government workers has dramatically risen in this same period. This divergence in the demand for science, technology, engineering, and mathematics (STEM) employees challenges government leaders to retain these highly demanded workers in the public sector.

Decades of psychological research across many industries has investigated what motivates workers and how best to incentivize them to increase productivity. Maslow and Herzberg, among others, theorized that adult workers have both intrinsic and extrinsic needs that drive their behaviors and resultant productivity. …

Characterization Of Sea Level Changes Along The Louisiana/Florida Shelf Using High Frequency (Hf) Radar Data And Sea Level Measurements, Uchenna Nwankwo

Dissertations

In this dissertation, three sea level studies in the Mississippi Bight (MSB) have been conducted. The first is an investigation into why VDatum, the vertical datum transformation tool of NOAA, has large errors in the western side of the MSB. The second is an estimation of the subinertial (>2 day timescale) shape of sea level over the high frequency radar (HFR) coverage in the MSB and to what extent it is in geostrophic balance. The third study examines the relative contribution of different mechanims to the subinertial sea level in the HFR coverage area. For the first study, NOAA …

A Mixed-Methods Study Examining The Difference Between Closed Captioning And Lexile Levels, Jim Pruitt

Dissertations

This experimental mixed-methods study explores what happens to student Lexile scores when they use closed captioning. Since the emergence of closed captioning tools in the 1980s, closed captioning has become more mainstream and easier to access today than at any other time in history (Rickelman et al., 1991). Thus, it is through harnessing this technology and bringing it into the classroom setting that the researcher of this study hopes to provide new approaches for educators that want to improve their student Lexile levels, while also incorporating the SAMR model within our increasingly technologically-focused classrooms (Crompton & Burke, 2018).

The quantitative …

Copolymer Microphase Separation, Properties, And Applications, Daniel Weller

Dissertations

Copolymers represent a broad, but critically important class of materials. Often having properties superior to either of its constituents, copolymers are used in virtually all industries including automotive, aerospace, coatings, packaging, and cosmetics. Certain copolymers microphase separate to form nanosized domains that improve the physical properties of the copolymer. The polymer community already has a thorough understanding of how phase separation occurs, but the commercialization of phase separating copolymers lags significantly behind academia. Many of the copolymers that exist that have been undercharacterized and underutilized. This dissertation examines two such polymers. The first, a hard polystyrene material with soft nanodomains. …

Receptor-Doped Organic Transistors: Transducing Anion Binding From Mixed Ionic-Electronic Transport, Anthony Benasco

Dissertations

Organic semiconductors based on π-conjugated polymers show remarkable properties such as high tolerance to structural defects, low processing temperature requirements, biocompatibility, ease of fabrication, and tunable properties. Conjugated polymers integrated into device arrays can exhibit collective properties sensitive to minor perturbations in the surrounding media. However, these devices rely on serendipitous sensitivity to the analyte of interest, and strategies for specific detection remain a considerable change. There remains a compelling, global need for technologies to monitor phosphate due to its prevalence in agricultural runoff, leading to fish kills and economic decline for commercial and recreational fisheries. The strong hydration energies …