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Full-Text Articles in Engineering

Material Characterization And Comparison Of Sol-Gel Deposited And Rf Magnetron Deposited Lead Zirconate Titanate Thin Films, Katherine Lynne Miles Nov 2022

Material Characterization And Comparison Of Sol-Gel Deposited And Rf Magnetron Deposited Lead Zirconate Titanate Thin Films, Katherine Lynne Miles

Mechanical Engineering ETDs

Lead zirconate titanate (PZT) has been a material of interest for sensor, actuator, and transducer applications in microelectromechanical systems (MEMS). This is due to their favorable piezoelectric, pyroelectric and ferroelectric properties. While various methods are available to deposit PZT thin films, radio frequency (RF) magnetron sputtering was selected to provide high quality PZT films with the added capability of batch processing. These sputter deposited PZT films were characterized to determine their internal film stress, Young’s modulus, composition, and structure. After characterization, the sputtered PZT samples were poled using corona poling and direct poling methods. As a means of comparison, commercially …


Assessment Of The Biocompatibilty, Stability, And Suitability Of Natural And Synthetic Polymers And Drugs In The Fda Approval Process, Phuong Anh Hoang Nguyen Aug 2019

Assessment Of The Biocompatibilty, Stability, And Suitability Of Natural And Synthetic Polymers And Drugs In The Fda Approval Process, Phuong Anh Hoang Nguyen

Biomedical Engineering ETDs

Regulation of the development, production, marketing, and sales of medical pharmaceuticals and devices in the United States fall under the regulatory functions of the Food and Drug Administration (FDA). The current FDA approval process takes an average of 10 years from start to completion, and costs over $100 million. As a result, companies use many different methods to find additional use of their drugs through marketing directly to the physician, or recycling of previously approved drug moieties. In this work, an evaluation of the in vitro and ex vivo biocompatibility of polymers and drugs in different phases of FDA approval …


Cellular Modification And Artificial Cell Construction, Jimin Guo May 2019

Cellular Modification And Artificial Cell Construction, Jimin Guo

Chemical and Biological Engineering ETDs

With all its complexities and different biofunctionalities, a cell is the basic structural and functional unit of all living organisms with the exception of viruses. In this dissertation, I demonstrated gain of function strategies of modifying mammalian cells using silicification and modular nanoparticle (NP) exoskeletons. In addition, I used a modular design concept to build a multifunctional artificial RBC system which can mimic the unique characteristics (e.g. shape, flexibility, the ability to carry oxygen, and long circulation times) of the native RBCs. Together, these cell modification or artificial cell construction strategies are expected to generate new mammalian cell-like structures with …


The Effect Of Defects And Surface Modification On Biomolecular Assembly And Transport, Haneen Martinez Mar 2019

The Effect Of Defects And Surface Modification On Biomolecular Assembly And Transport, Haneen Martinez

Nanoscience and Microsystems ETDs

Nanoscale transport using the kinesin-microtubule (MT) biomolecular system has been successfully used in a wide range of nanotechnological applications including self-assembly, nanofluidic transport, and biosensing. Most of these applications use the ‘gliding motility geometry’, in which surface-adhered kinesin motors attach and propel MT filaments across the surface, a process driven by ATP hydrolysis. It has been demonstrated that active assembly facilitated by these biomolecular motors results in complex, non-equilibrium nanostructures currently unattainable through conventional self-assembly methods. In particular, MTs functionalized with biotin assemble into rings and spools upon introduction of streptavidin and/or streptavidin-coated nanoparticles. Upon closer examination of these structures …


The Endocytotic Fate Of A Mesoporous Silica Nanoparticle Supported Lipid Bylayer Crispr Delivery Vehicle, Angelea Maestas-Olguin Jan 2019

The Endocytotic Fate Of A Mesoporous Silica Nanoparticle Supported Lipid Bylayer Crispr Delivery Vehicle, Angelea Maestas-Olguin

2019 Award Winners

No abstract provided.


Chemically Modified Monolayer Surfaces Influence Valvular Interstitial Cell Attachment And Differentiation For Heart Valve Tissue Engineering, Matthew N. Rush Dec 2018

Chemically Modified Monolayer Surfaces Influence Valvular Interstitial Cell Attachment And Differentiation For Heart Valve Tissue Engineering, Matthew N. Rush

Nanoscience and Microsystems ETDs

As a cell mediated-process, valvular heart disease (VHD) results in significant morbidity and mortality world-wide. In the US alone, valvular heart disease VHD is estimated to affect 2.5% of the population with a disproportionate impact on an increasing elderly populous. It is well understood that the primary driver for valvular calcification is the differentiation of valvular interstitial cells (VICs) into an osteoblastic-like phenotype. However, the factors leading to the onset of osteoblastic-like VICs (obVICs) and resulting calcification are not fully understood and a more complete characterization of VIC differentiation and phenotypic change is required before treatment of valve disease or …


Improving The Palatability Of Colonoscopy Preparations, Phuong Anh Hoang Nguyen, Darnell Leon Cuylear, Heather Elizabeth Canavan Nov 2018

Improving The Palatability Of Colonoscopy Preparations, Phuong Anh Hoang Nguyen, Darnell Leon Cuylear, Heather Elizabeth Canavan

Shared Knowledge Conference

Colorectal cancer (CRC) is the second leading cause of cancer-related deaths in the United States. The most reliable screening method of CRC is a colonoscopy which requires a 4-Liter polymer with electrolytes preparation. Two in five patients are non-compliant to their colonoscopy schedules, with many patients who abstain reporting refusal due to significant discomfort associated with this preparation. Furthermore, there are distinct gender differences in the tolerance of colonoscopy preparations in male and female populations. We hypothesize the differences in clinic are a result of toxic effects of the drug associated with poor mixing by individual patients. PEG, the drug, …


An Engineer’S Take On The Bone-Ligament Interface: Utilizing Novel Technology To Improve Clinical Outcomes, Emma Garcia Nov 2018

An Engineer’S Take On The Bone-Ligament Interface: Utilizing Novel Technology To Improve Clinical Outcomes, Emma Garcia

Shared Knowledge Conference

Ligament repair is a common surgical practice with a significant lack of viable replacements. The current gold standard for repair is the use of tendon grafts from cadavers or from another place in the patient’s body; however, these often cause more problems than they solve including immune responses or a lack of mobility in another place in the body. Synthetic replacements are of growing interest, though the ability to mimic the complex structure of the ligament and how it connects to the bone remains an obstacle. Our lab built a 3D bioprinter combined with an electrospinner to address this complicated …


Improving The Palatability Of Colonoscopy Preparations, Phuong Anh Hoang Nguyen, Sarah Mounho, Darnell Cuylear, Heather Canavan Nov 2018

Improving The Palatability Of Colonoscopy Preparations, Phuong Anh Hoang Nguyen, Sarah Mounho, Darnell Cuylear, Heather Canavan

Shared Knowledge Conference

Colorectal cancer (CRC) is the second leading cause of cancer-related deaths in the United States. The most reliable screening method of CRC is a colonoscopy which requires a 4-Liter polymer with electrolytes preparation. Two in five patients are non-compliant to their colonoscopy schedules, with many patients who abstain reporting refusal due to significant discomfort associated with this preparation. Furthermore, there are distinct gender differences in the tolerance of colonoscopy preparations in male and female populations. We hypothesize the differences in clinic are a result of toxic effects of the drug associated with poor mixing by individual patients. PEG, the drug, …


3d Bioprinting And Near-Field Electrospinning Composite Scaffolds For The Bone-Ligament Interface, Emma Garcia, Christina Salas, Matthew N. Rush, Christopher Buksa, Marissa Perez, Ava Mauser, Steven Nery, Fermin Prieto, Darielys Morales Nov 2018

3d Bioprinting And Near-Field Electrospinning Composite Scaffolds For The Bone-Ligament Interface, Emma Garcia, Christina Salas, Matthew N. Rush, Christopher Buksa, Marissa Perez, Ava Mauser, Steven Nery, Fermin Prieto, Darielys Morales

Shared Knowledge Conference

3D bioprinting is an additive manufacturing technique that can utilize a range of bioactive materials to construct specific architectures that mimic native tissue. Near-field electrospinning (NFE) offers precise alignment control to create non-woven mats with high tensile strengths. We built a custom E-spin printer that enables layer-by-layer alternating deposition between 3D bioprinting and NFE to create composite scaffolds for the bone-ligament interface. This complex region is difficult to simulate due to its functionally graded mechanical and biochemical properties. We created NFE poly(caprolactone) highly aligned micro-fibers which formed collagen fibril-like bundles. Poly(ethylene glycol) diacrylate with decellularized bone was encased in the …


Developing Droplet Based 3d Cell Culture Methods To Enable Investigations Of The Chemical Tumor Microenvironment, Jacqueline A. De Lora Jul 2018

Developing Droplet Based 3d Cell Culture Methods To Enable Investigations Of The Chemical Tumor Microenvironment, Jacqueline A. De Lora

Biomedical Sciences ETDs

Adaptation of cancer cells to changes in the biochemical microenvironment in an expanding tumor mass is a crucial aspect of malignant progression, tumor metabolism, and drug efficacy. In vitro, it is challenging to mimic the evolution of biochemical gradients and the cellular heterogeneity that characterizes cancer tissues found in vivo. It is well accepted that more realistic and controllable in vitro 3D model systems are required to improve the overall cancer research paradigm and thus improve on the translation of results, but multidisciplinary approaches are needed for these advances. This work develops such approaches and demonstrates that new droplet-based cell-encapsulation …


Designing Synthetic Environments To Control Valvular Interstital Cells In Vitro, Kent E. Coombs May 2018

Designing Synthetic Environments To Control Valvular Interstital Cells In Vitro, Kent E. Coombs

Biomedical Sciences ETDs

Aortic valve disease (AVD) is a large contributor to health costs in the United States affecting 2.8% of the population greater than 75 years old. With a growing elderly population due to medical advances, AVD will continue to rise in prevalence over time. Current treatments for AVD are insufficient due to a lack of preventative therapies and the bioprosthetic valves used for surgical replacement have major limitations. Tissue engineered heart valves (TEHVs) present an ideal solution to current AVD needs because of their biocompatibility, capability to integrate with the host’s tissue, and ability to utilize the natural repair mechanisms of …