Digital Commons Network^™

Perceptions Of Barriers To Leadership Appointment And Promotion Of African American Female Commissioned Officers In The United States Military, Beverly Henderson Davis

Doctoral Dissertations

The U.S. military is perceived by many to be the example of workplace meritocracy, but historical studies have shown that the perceptions of African American female commissioned officers run counter to that belief. The military has as its goal the movement from a diverse fighting force to one that is totally inclusive of all members. The purpose of this study was to gather insights into whether the military has moved toward full integration from the viewpoint of the demographic that has shown the least confidence in the accomplishment of that task.

This qualitative study involved 12 participants: active duty, retired, …

Exploration Of Associate Degree Nursing Graduates' Progression To The Baccalaureate In Nursing: Experiences And Predictive Variables, Linda Marie Perfetto

Doctoral Dissertations

Applying the post-positivistic framework of Thomas Kuhn, the purpose of this dissertation is to demonstrate and explore the educational advancement of associate degree nurses. Community colleges in the United States make quality and affordable higher education accessible to individuals who may not otherwise pursue it. While these institutions attract diverse and talented learners, community colleges make rewarding and life-altering careers a reality for many. For associate degree nurses, this educational opportunity serves as a strong foundation upon which to build a meaningful career. Increased emphasis on the educational advancement of associate degree nurses began with the 2010 Institute of Medicine …

Cyclic Durability Of Thermal Barrier Coatings Subject To Cmas Attack, Alan Harris

Doctoral Dissertations

Thermal barrier coatings (TBCs) are critical in modern gas turbine engines, increasing operating temperature, efficiency, and component life. Engines have reached temperatures at which ingested debris (CMAS) forms silicate melts that chemically and mechanically attack TBCs, leading to premature failure. New, CMAS-resistant coatings must be validated under conditions that recreate real-world TBC-CMAS interactions. No standardized testing to perform these analyses currently exists.

A cyclic thermal gradient rig with incremental CMAS deposition was developed based on modified literature designs. Tests performed using literature-based parameters showed TBC-CMAS interactions and failure morphology deemed not real-world representative by an engine manufacturer. The results were …

Actin Assembly And Cell-To-Cell Transmission By Enterohemorrhagic And Enteropathogenic E. Coli, Katrina Velle

Doctoral Dissertations

Archival abstract submitted

Development Of A Pain Management Life History Calendar, Jennifer Hehl

Doctoral Dissertations

The purpose of this study was to develop and test a computerized pain management life history calendar (PMLHC) for use with older adults with osteoarthritis. A two-phase, descriptive research design was used to test the instrument for clinical and research applications. In Phase 1 focus groups, providers (N = 10) shared their thoughts of a mockup PMLHC output. During Phase 2, community dwelling older adults (N = 24) self-administered a PMLHC and were interviewed. An iterative process was used to refine the instrument using feedback from participants and researcher observations.

Content analysis on transcripts of audio-recordings from focus …

Conjugated Polymer-Based Functional Materials For Wearable Electronics: Electrochromism, Mengfang Li

Doctoral Dissertations

Archival abstract submitted

Information-Centric Design And Implementation For Underwater Acoustic Networks, Robert Martin

Doctoral Dissertations

Over the past decade, Underwater Acoustic Networks (UANs) have received extensive attention due to their vast benefits in academia and industry alike. However, due to the overall magnitude and harsh characteristics of underwater environments, standard wireless network techniques will fail because current technology and energy restrictions limit underwater devices due to delayed acoustic communications. To help manage these limitations we utilize Information-Centric Networking (ICN). More importantly, we look at ICN's paradigm shift from traditional TCP/IP architecture to improve data handling and enhance network efficiency. By utilizing some of ICN's techniques, such as data naming hierarchy, we can reevaluate each component …

Career Advancement Experiences Of Female Faculty Across African, Latinx, And Asian Diasporas In Athletic Training Education Programs: The Impact Of Workplace Microaggressions And Mentorship, Carrie Graham

Doctoral Dissertations

In the past 10 years, diversity among students pursuing athletic training has increased significantly. However, diversity among athletic training education program faculty, particularly females across African, Latinx, and Asian Diasporas (ALA Diasporas), lags student diversity. Diverse females are underrepresented among tenured faculty and have fewer opportunities for program leadership positions. To understand career advancement of diverse female faculty in athletic training education programs, I posed two research questions: What are the career advancement experiences of female faculty across African, Latinx, and Asian Diasporas working in athletic training education programs? And, how do they engage with mentors to support their career …

Bedform Geometry And Bedload Sediment Flux In Coastal Wave, Current, And Combined Wave-Current Flows, Meagan Wengrove

Doctoral Dissertations

Ripples and megaripples aggregate our coastlines, inlets, and rivers. This dissertation provides evidence for the contribution of small scale bedform migration to the evolution of larger coastal morphology. Using the connection between scales as a justification for continued research into the dynamics of growth and sediment flux associated with the mobility of ripples and megaripples in our coastal areas, this dissertation examines the dynamics between current dominant, wave dominant, and combined wave-current dominant bedforms on the multi-ripple and intra-ripple scales. Finally, this dissertation proposes that the bedload sediment flux is correlated with the total kinetic energy in the flow field …

Teaching Complex Content In Healthcare: A Comparison Of The Effect Of Three Types Of Multimedia Pretraining On Schematic Knowledge And Near Transfer, Melisa Patrice Kaye

Doctoral Dissertations

Challenged to teach complex content to students, university educators in healthcare disciplines face a practical need for effective pedagogical approaches. The preponderance of multimedia and digital resources in and beyond college classrooms suggests that solutions to teaching complex content should leverage educational technology and multimedia resources. The multimedia principle of pretraining is one effective way to augment complex content learning. The pretraining principle specifies that learning is more effective when the names and characteristics of main terms and concepts are introduced before more nuanced and complex content is presented.

The purpose of this study was to investigate three approaches to …

The Perceptions And Lived Experiences Of African American Male Presidents In California Community Colleges, Tyree L. Robinson

Doctoral Dissertations

Current research has shown racial disparities and inequities among African American men who desire to be community college presidents in California, or already hold the position. This study explored why California has only 7 African American community college presidents on 115 campuses; how to overcome obstacles to attain the presidency position; what life/work experiences assists current presidents in their leadership positions in higher education, as well as each president’s trajectory that ultimately led them to the presidency. The study explored factors that have kept African Americans out of higher education leadership roles such as the presidency.

A Geospatial Analysis Of A Transit Program On California Community College Students, Alicia Kathryn De Toro

Doctoral Dissertations

Subsidized transit policy is a strategy used to lessen environmental impacts and increase institutional accessibility in higher education. Program funding to support this subsidized transit policy can vary between institutions. This research focuses on the geographic analysis of Eco Pass, a student led initiative implemented in the Foothill De Anza Community College District in California to offset transportation costs for students. Through the use of Environmental Science Research Institute software, the research aimed to determine which geographic areas, if any, were of high and low probability of Eco Pass use from data during 2011-2017 using Tobler’s first law of geography. …

Integrative Machine Learning And Network Mining Models For The Inference Of Regulatory Elements And Interactions In Human Cells, Asa Thibodeau

Doctoral Dissertations

With the increase in diverse genome profiling technologies and publicly available ontology databases ranging from open chromatin profiles to the 3D structure of the genome, it is imperative to build novel computational methods that take full advantage of these diverse datasets to uncover the regulatory mechanisms behind cellular functions. Integrating these datasets offers the opportunity to identify regulatory elements (i.e., promoter, enhancers, etc.) and interactions critical for cell-type-specific functions. Here, the goal’s two fold: 1) inference of regulatory interactions and networks from 3D chromatin interaction datasets and 2) inference of cell-specific and non-specific regulatory elements such as enhancers (regulatory elements …

Modeling, Design And Analysis Of Smart Ocean Energy Systems, Taofeek A. Orekan

Doctoral Dissertations

Ocean energy offers the highest energy density when compared to other renewable energy resources, and its energy potentials is enormous. As ocean energy converter technology continues to advance, vigorous testing methodology, new design modeling, and assessments of the device performances under different wave conditions become critically important. This work presents the development of a new type of wave energy converter, Smart-WEC, from concept to prototype stage. It utilizes a direct drive linear generator to extract energy from the motion of ocean waves. An integrated dynamic model of Smart-WEC is developed to evaluate its dynamic behavior. Furthermore, Smart-WEC has the capability …

Engineering Tools To Further Neuroscientific Investigation, Jessica L. Scoggin

Doctoral Dissertations

Custom equipment is often necessary in the laboratory. However, costs for such equipment can be high and efficient systems with lower cost are an advantage. In this work, we showed that a cellular environment to keep cells healthy and viable for five hours on a microscope could be created using FDM printing (Chapter 3). Design criteria were that it maintained correct temperature, high humidity and proper pH to control the environment as discussed in Chapter 2. Results indicated that cells would maintain viability for up to five hours, but redesigns needed to be made for extending viability past five hours. …

Cost-Effective Use Of Follow-Up Colonoscopies And Fecal Immunochemical Tests In Colorectal Cancer Screening, Grace N. Joseph

Doctoral Dissertations

Colorectal cancer (CRC), if not detected early, can be costly and detrimental to one's health. Screening techniques for colorectal cancer can help find and remove adenomas in an effort to prevent future CRC. A colonoscopy has the potential of identifying CRC early as well as preventing the disease. Fecal Immunochemical Tests (FITs) is an initial non-invasive screening technique that identifies the presence of the disease, and needs to be followed by a more invasive test (like colonoscopy) if anything is detected. However, the optimal frequency for follow-up colonoscopy, and screening colonoscopy with FITs is unknown, and may vary based on …

Metal Containing Polymers As Dielectrics: A Co-Design Approach To Material Space Expansion, Shamima Nasreen

Doctoral Dissertations

“Metals” is known to play an integral part of human life in its numerous form from the dawn of civilization whether as an everyday mechanistic tool as well as important biological nutrients. They are found in everything around us from power system as wind turbines to medical instrument as diabetes test strips, construction materials to transportation development, and needless to say in our essential everyday electronic equipment. To imagine life without electricity, road without cars and medical care without many of today’s medical devices are impossible. The uses of metals and derivative of metals become the utmost necessity beyond replacement. …

Impact Of Protein Internal Dynamics, Process And Formulation Variables On Freeze-Dried Protein Quality Attributes, Rui Fang

Doctoral Dissertations

Lyophilization has been used to improve the quality of pharmaceutical proteins when sufficient stability in the aqueous state cannot be achieved. However, due to inherent challenges in both the freeze-drying process and formulation of proteins for freeze drying, efficient delivery of drug products with uniformly improved stability is not trivial. The overall objective of this work was to investigate freeze-dried protein quality attributes affected by stress factors arising from process and formulation.

The natural variation in ice nucleation temperature (T_n) necessitates the control of ice nucleation to ensure uniformity in product quality across a batch. Further, it is …

Improvement Of Metal, Oxide, & Carbon Nanomaterials Via Thin Film Coatings And Advanced Microscopic Characterization Of Mesoporous Materials, Shannon Poges

Doctoral Dissertations

Thin films were deposited on metal, oxide, and carbon nanomaterials via chemical deposition techniques. Experiments were done in a methodical manor in order to obtain desired thickness and morphology of these coatings. Advanced characterization methods were employed on these and colleague produced catalyst materials in order to answer complex questions about their chemical make-up.

Electroless deposition of aluminum using room temperature ionic liquids and liquid reducing agents is extremely water sensitive and has only been successful in glove boxes with deposition on copper or glass substrates. We have successfully brought the deposition out of the glove box using Schlenk techniques. …

A Quantitative Understanding Of Moisture Induced Flow Variability And Triboelectric Charging In Pharmaceutical Powders, Raj Mukherjee

Doctoral Dissertations

'Archival abstract submitted'

Numerical Weather Model Based Adjustment Of Satellite Precipitation Products And Hydrologic Evaluations, Xinxuan Zhang

Doctoral Dissertations

The quantification of heavy precipitation events over mountainous regions has been a challenge for all types of satellite precipitation products. This research developed a numerical weather model-based adjustment technique to correct satellite precipitation estimates for HPEs. To successfully apply the technique, there are two prerequisites: i) the raw satellite data captures the relative spatial and temporal variabilities of precipitation (i.e. no significant surface contamination effects on satellite precipitation detection), and ii) the model provides relatively accurate precipitation outputs in terms of overall magnitude (not necessarily location). The technique was demonstrated over mountainous areas all over the world representing varying terrain …

Fabrication And Characterization Of Collagen-Apatite Composites For Bone Tissue Engineering, Changmin Hu

Doctoral Dissertations

Due to the high demand of scaffolds for treating bone fractures every year, biomimetic coatings and scaffolds resembling the composition and structure of natural bone are of keen interest of bone tissue engineers. In this research, a series of biomimetic coatings and scaffolds have been developed, including biomimetic apatite coatings, biomimetic collagen-apatite composite coatings, intrafibrillar calcified collagen fibrils, intrafibrillar silicified collagen fibrils, and intrafibrillar calcified collagen scaffolds.

First, a crack-free apatite coating was deposited on the surface-treated Ti6Al4V substrate using a biomimetic process, in which the surface-treated titanium substrate was immersed in a modified simulated body fluid (m-SBF). Dual-beam focused …

Renewable Fuels Produced From Biomass Pyrolysis Vapors: Catalysis And Reaction Engineering, David Pierce Gamliel

Doctoral Dissertations

At present, lignocellulosic biomass is the only renewable and available resource capable of supplanting fossil fuel resources. Fast pyrolysis is the conversion of biomass at elevated temperature, high heating rate and under inert atmosphere to produce bio-oil. This bio-oil is a blend of oxygenated hydrocarbons, which must be upgraded prior to use as a transportation fuel. The focus of this thesis is the investigation of bio-oil upgrading reaction pathways and catalysts for the production of biofuels.

There are two primary pathways for pyrolysis vapor upgrading: catalytic cracking and hydrodeoxygenation (HDO). During catalytic cracking, pyrolysis vapors react over the acid sites …

Nanostructured Multi-Functional Hybrid Nanocoatings From One-Step Coassembly, Jingjing Liu

Doctoral Dissertations

In this dissertation, a novel approach to fabricate organic/inorganic nanocoatings via a large-scale one-step coassembly process has been developed. The fabricated nanocoatings contain a high concentration of nanosheets (up to 70 wt. %) that can be well aligned along the substrate surface. A series of nanocoatings based on polyvinyl alcohol (PVA) together with various nanosheets including montmorillonite (MMT), laponite (LP), α-zirconium phosphate (ZrP), and graphene oxide (GO) were successfully fabricated using this one-step coassembly process. Different from other methods, this approach offers a high-speed one-step coassembly, in which hundreds of nanosheets can be aligned along the flow direction to form …

Strain Engineering Of Two-Dimensional (2d) Materials At The Atomic Scales, Jin Wang

Doctoral Dissertations

Since the discovery of graphene, there has been a fast-growing interest in fabricating ultrathin 2-dimensional (2D) films and nano flakes out of materials with layered structures. Among all these materials, transition metal dichalcogenides (TMDs) such as MoS₂, WSe₂, HfS₂ and ReS₂, are semiconductors that show significant promise for use in electronics, optoelectronics, and catalytic applications. These materials comprise of covalent interactions between the atoms within the layer and van der Waals (vdW) interactions between the layers. Recent experiments have demonstrated that strain engineering is an effective method to tune the electronic, magnetic and …

Power Management Systems For Biomass-Based Energy Harvesting, Ridvan Umaz

Doctoral Dissertations

Archival abstract submitted.

Service Response And Evaluation Of Prestressed Concrete Bridges Through Load Testing, Eli Saul Hernandez Ramos

Doctoral Dissertations

"During the last two decades, self-consolidating concrete (SCC) has emerged as an alternative to produce structures with longer life expectancy. Despite the advantages that come with using SCC, there are some concerns related to its structural and serviceability response. The effect of the larger paste content and smaller coarse aggregate size is of particular interest because this combination may inhibit the development of the SCC's target mechanical properties. Field tests are an effective method to monitor the service response of infrastructure. In addition, field tests have largely confirmed reserves of strength capacity in existing bridges despite their visual condition and …

Atomic Layer Deposition Prepared Nanostructured Materials For Various Catalytic Reactions, Xiaofeng Wang

Doctoral Dissertations

"Atomic layer deposition (ALD) has been widely used for thin film coating and metal nanoparticles (NPs) preparation. In this report, the applications of ALD prepared nanostructured materials in catalysis were examined.

Highly dispersed Pt monometallic catalysts with different substrates and multi-walled carbon nanotubes (MWCNTs) supported Pt-Co bimetallic catalysts were synthesized by ALD for selective hydrogenation of α, β-unsaturated aldehydes to unsaturated alcohols (UA). Pt/MWCNTs showed the highest selectivity of UA in selective hydrogenation of citral, as compared to Pt/SiO₂, Pt/ALD-Al₂O₃, and Pt/γ-Al₂O₃. After adding Co, the highest selectivity was achieved …

Micro-Slotting Technique For Measurement Of Local Residual Stress In Metallic Materials, Elizabeth Anne Burns

Doctoral Dissertations

"Micro-slotting, a micro-scale relaxation residual stress measurement technique, has been shown in recent years to be a reliable method for measuring local residual stresses in metallic materials. This technique employs an SEM-focused ion beam system for milling and imaging, digital image correlation software to track displacements due to residual stress relaxation, and finite element analysis for interpolation of the original local stress state. In this research, a micro-slotting procedure was established using finite element models and was used to obtain sub-surface residual stress measurements on machined and shot peened planar Ti-6Al-4V samples. These measurements were compared to macro-scale XRD residual …

Quantitative Phase-Field Modeling Of Crack Propagation In Multi-Phase Materials, Arezoo Emdadi

Doctoral Dissertations

”Research presented in this dissertation is focused on developing and validating a computational framework for study of crack propagation in polycrystalline composite ceramics capable of designing micro-architectures of phases to improve fracture toughness and damage tolerance of ZrB₂-based ultra-high temperature ceramics (UHTCs). A quantitative phase-field model based on the regularized formulation of Griffith’s theory is presented for crack propagation in homogenous and heterogeneous brittle materials. This model utilizes correction parameters in the total free energy functional and mechanical equilibrium equation within the crack diffusive area to ensure that the maximum stress in front of the crack tip is …