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Cardiac Regenerative Medicine: Insights From Healthy And Diseased Engineered Tissues, Pamela Grace Hitscherich

Dissertations

Cardiovascular disease remains the leading cause of mortality in the United States. Current tissue engineering approaches have fallen short of promoting fully functional cardiovascular cells and the post-myocardial infarction microenvironment is still not well understood. These gaps in knowledge are addressed in this dissertation through the development of in vitro engineered cardiac tissues using electroactive materials to enhance the differentiation of pluripotent stem cell derived cardiomyocytes and through the development of in vitro myocardial inflammation models dedicated to understanding cardiomyocytes and macrophages interactions.

Specifically, piezoelectric poly (vinylidene fluoride-trifluoroethylene) (PVDF-TrFE) supports the attachment and survival of mouse embryonic stem cell derived …

Electroless Nickel Plating And Spark Plasma Sintering Of Nano Zro2 For Mechanical Property Enhancement, Kunlong Jia

McKelvey School of Engineering Theses & Dissertations

A new approach of combined electroless nickel plating (ENP) and spark plasma sintering (SPS) was used to determine the feasibility of fracture toughness improvement of ZrO2. Nano-grained yttria stabilized zirconia (YSZ) particles of 100nm average diameter were coated with about 1-5 nm of nickel coating by ENP. To reduce nano particle agglomeration throughout the ENP process; vigorous agitation with an ultrasonic horn was used. The coated powder was characterized using Scanning Electron Microscopy (SEM), Energy-dispersive X-ray spectroscopy (EDX) and Transmission electron microscopy (TEM) to study the microstructure and coating characteristics. The coating was identified to be predominantly nickel and of …

Effect Of Strong Electrolyte Containing Gelling Aids On The Sol-Gel Transition Temperature Of Hypromellose 2910, Elnaz Sadeghi

Biomedical Engineering ETDs

Hypromellose, or hydroxypropyl methylcellulose (HPMC) - has been widely used for biomedical and pharmaceutical applications due to its advantages, including that it is modifiable in terms of viscosity, and it has the ability to form thermally reversible hydrogels. The thermal gelation temperature (T_Gel) of a given HPMC solution strongly depends on its characteristic grade and the solution concentration. Applying certain additives can modify the T_Gel even further; depending on their nature and concentration. With the addition of said additives, a lower or higher T_Gel can be obtained. For example, the addition of sodium chloride (NaCl) reduces …

Spatial Exploration Of Trace Metals In Near-Surface Water And Soil In The Bolivian Altiplano, Lizzie Wilson

Civil and Environmental Engineering Theses and Dissertations

We analyzed soil and groundwater samples from the Bolivian Altiplano for trace metal concentrations, correlations and partitioning trends. Total digestion, sequential extraction and loss on ignition experiments were performed on soil samples. We ran aqueous samples on an ICP-MS. Results were analyzed to identify trace metal concentrations and find any significant correlations. We generated interpolated maps in ArcGIS to spatially analyze results. Results for elevated concentrations of interest were divided into sub-groups of organophilic metals, oxoanions and divalent metals and include vanadium, arsenic, selenium, zinc, nickel, lead, cobalt, uranium, copper and manganese. These elements are likely naturally sourced. We found …

Fluid Structure Interaction Study Of The Obstructive Sleep Apnea And Surgical Treatment Using Suture-Patch Device On The Patient’S Tongue, Yang Liu

UNLV Theses, Dissertations, Professional Papers, and Capstones

Up to 14% of the U.S. population is estimated to have obstructive sleep apnea (OSA) related to obesity, and there is increased incidence occurring worldwide. While treatment with continuous positive airway pressure (CPAP) resolves airway obstruction, patient compliance is relatively low. Alternative interventions are available to treat OSA patients; however, their outcomes have had variable results. For example, current technologies have demonstrated an inability to define and treat the specific anatomical site(s) causing the obstruction, resulting in suboptimal modifications of the airway and poor control of OSA.

In the current study, a three-dimensional (3-D) fluid-structure interaction (FSI) numerical simulation has …

Virtual Reality Simulation Of Glenoid Reaming Procedure, Mohammadreza Faieghi

Electronic Thesis and Dissertation Repository

Glenoid reaming is a bone machining operation in Total Shoulder Arthroplasty (TSA) in which the glenoid bone is resurfaced to make intimate contact with implant undersurface. While this step is crucial for the longevity of TSA, many surgeons find it technically challenging. With the recent advances in Virtual Reality (VR) simulations, it has become possible to realistically replicate complicated operations without any need for patients or cadavers, and at the same time, provide quantitative feedback to improve surgeons' psycho-motor skills. In light of these advantages, the current thesis intends to develop tools and methods required for construction of a VR …

Design And Testing Of A Sheath Device To Secure Rotator Cuff Anchors In Osteoporotic Bone, Alissa Smith

Masters Theses

A rotator cuff tear is a common injury that affects many elderly people. These tears vary in severity, with moderate to severe tears requiring surgery. In rotator cuff surgery, bone anchors are used to re-attach the supraspinatus tendon to the humerus. This surgery is difficult in many older patients because aging bones become osteoporotic, or soft, and thus inadequate for securing bone anchors. Studies confirm that osteoporotic bone is a contributing factor of implant failure. A finned sheath concept was designed, developed, and tested to ensure securement of the bone anchors during and after rotator cuff repair. The sheath interacts …

Examining The Use Of Idealized Granular Material In Validated Dem Simulations, Anjana Thoroppady Kittu

Graduate Theses and Dissertations

Discrete element method (DEM) modeling, is becoming widely used for understanding the micro-mechanical behavior of granular materials at the particle level. This dissertation presents important considerations regarding the experimental boundary conditions and idealized granular materials used in DEM validations.

A common issue in DEM validation studies for direct shear and direct simple shear is selecting top and bottom cap boundary conditions that allow for shear transmission while also being efficiently modeled in the DEM simulations. While the traditional grid boundary types used in the laboratory can be replicated in the numerical models, researchers have also used fixed-particle boundaries, sawtooth boundaries, …

Morphological Features Of Dysplastic Progression In Epithelium: Quantification Of Cytological, Microendoscopic, And Second Harmonic Generation Images, Sandra Patricia Gordon

Graduate Theses and Dissertations

Advances in imaging technology have led to a variety of available clinical and investigational systems. In this collection of studies, we tested the relevance of morphological image feature quantification on several imaging systems and epithelial tissues. Quantification carries the benefit of creating numerical baselines and thresholds of healthy and abnormal tissues, to potentially aid clinicians in determining a diagnosis, as well as providing researchers with standardized, unbiased results for future dissemination and comparison.

Morphological image features in proflavine stained oral cells were compared qualitatively to traditional Giemsa stained cells, and then we quantified the nuclear to cytoplasm ratio. We determined …

Engineered Coating Of Natural Fibers And Oil-Water Interfaces With Self-Assembly Of Clay Nanotubes, Abhishek Panchal

Doctoral Dissertations

Taking into consideration two different types of surfaces, this dissertation proposes techniques to coat the surface of natural fibers and oil-water interfaces by spontaneous self-assembly of halloysite clay nanotubes. The material of choice, halloysite clay, is a widely available natural resource and can be used after minimal processing. In regards to chemical composition, halloysite clay resembles aluminosilicate mineral kaolin; physically, a defect in the crystal structure ordering causes the sheets of kaolinite to roll into halloysite nanotubes. The dimensions of halloysite nanotubes are dependent on the source, but generally vary from 200 nm to 3 µm in length, 100-150 nm …

Analysis Of Printed Electronic Adhesion, Electrical, Mechanical, And Thermal Performance For Resilient Hybrid Electronics, Clayton Neff

USF Tampa Graduate Theses and Dissertations

Today’s state of the art additive manufacturing (AM) systems have the ability to fabricate multi-material devices with novel capabilities that were previously constrained by traditional manufacturing. AM machines fuse or deposit material in an additive fashion only where necessary, thus unlocking advantages of mass customization, no part-specific tooling, near arbitrary geometric complexity, and reduced lead times and cost. The combination of conductive ink micro-dispensing AM process with hybrid manufacturing processes including: laser machining, CNC machining, and pick & place enables the fabrication of printed electronics. Printed electronics exploit the integration of AM with hybrid processes and allow embedded and/or conformal …

Piezoelectric-Based Cardiac Monitoring Portable System, Shina Siamak Mokhtari

Electrical Engineering Theses

In this thesis, a portable-based cardiac monitoring system is discussed, which helps to keep a check on the corresponding patient vitals. This work describes the design and development of a Bluetooth system, incorporating a piezoelectric sensor-sheet. The demonstrated prototype avoids the need for collecting the signals with wires. When the Bluetooth-connected piezoelectric sensor is attached to the human chest, the cardiac mechanical activity will induce a local strain in the active piezoelectric materials layer. This strain is converted to an electrical output voltage which is then collected and transmitted through the Bluetooth system. Piezoelectric theory and signal processing methods are …

Hyperspectral Imaging For Characterizing Single Plasmonic Nanostructure And Single-Cell Analysis, Nishir Sanatkumar Mehta

LSU Master's Theses

Orientation of plasmonic nanostructures is an important feature in many nanoscale applications such as photovoltaics, catalyst, biosensors DNA interactions, protein detections, hotspot of surface-enhanced Raman spectroscopy (SERS), and fluorescence resonant energy transfer (FRET) experiments. Silver nanocubes with significant spectral signatures between 400-700 nm are observed in this experimental research. Whereas study of single cells will enable the analysis of cell-to-cell variations within a heterogeneous population. These variations are important for further analysis and understanding of disease propagation, drug development, stem cell differentiation, embryos development, and how cells respond to each other and their environment. Adipose-derived mesenchymal stem cells possess the …

Minutes & Seconds: The Scientists, Patrick Aievoli

Zea E-Books Collection

Minutes & Seconds, is a captivating intelligible read for those who strive to understand where the “what if” moment has gone. Succeeding his other captivating books, Aievoli’s deep introspective lens dials his readers in to awaken the proverbial sleeping giant inside of our consciousness. He designs an insightful exciting romp through the surreal landscape of our society and illustrates how various pioneers have lead us to a crossroads. I’m truly impressed with Aievoli’s perspicacious comprehension of where digital has taken us through the hands of these select individuals. --Sequoyah Wharton

In creating Minutes & Seconds, Aievoli has assembled an interesting …

Fabricating Functionally Graded Materials By Ceramic On-Demand Extrusion With Dynamic Mixing, Wenbin Li, Austin J. Martin, Benjamin Kroehler, Alexander M. Henderson, Tieshu Huang, Jeremy Lee Watts, Greg Hilmas, Ming-Chuan Leu

Materials Science and Engineering Faculty Research & Creative Works

Ceramic On-Demand Extrusion (CODE) is an extrusion-based additive manufacturing process recently developed for fabricating dense, functional ceramic components. Presented in this paper is a further development of this process focusing on fabrication of functionally graded materials (FGM). A dynamic mixing mechanism was developed for mixing constituent ceramic pastes, and an extrusion control scheme was developed for fabricating specimens with desired material compositions graded in real time. FGM specimens with compositions graded between Al₂O₃ and ZrO₂ were fabricated and ultimately densified by sintering to validate the effectiveness of the CODE process for FGM fabrication. Energy dispersive spectroscopy …

Effects Of Lighting And Noise On Performance And Situation Awareness In An Air Traffic Control Task, Saralee Pruksaritanon, Andrew Dattel Ph.D., Steven Hampton Ed.D.

National Training Aircraft Symposium (NTAS)

Work environment influences an individual’s performance and situation awareness (SA). This study aims to investigate the effects of lighting and noise levels on performance and situation awareness in an air traffic control (ATC) task. These two variables are important in the domain of ATC because the task requires an individual to receive and process information both visually and auditorily. The results are useful for designing air traffic control rooms, which are set differently among different air navigation service providers. The subjects are 16 students majoring in Air Traffic Management (ATM) at Embry-Riddle Aeronautical University (ERAU) – Daytona Beach, FL. The …

Design Of Parallel Robot For Dental Articulation And Its Optimization, Abulimiti Delimulati

Department of Mechanical and Materials Engineering: Dissertations, Theses, and Student Research

A dental articulator is a mechanical device used to simulate the relative position and motion between the upper and lower jaw when constructing and testing dental prostheses. Typically, it can be adjusted to approximate patient-specific jaw kinematics in order to analogue the static relationship and specific motions of a patient’s mandible to maxilla. However, the use of dental articulators is essentially a trial-and-error method in order to fine-tune fit and function of a dental prosthesis. Some of the most advanced current dental articulators can reproduce the position and the motion passively; furthermore, dentists need special training for measuring patients’ maxillofacial …

Binder Jetting Additive Manufacturing Process Fundamentals And The Resultant Influences On Part Quality., Hadi Miyanaji

Electronic Theses and Dissertations

Binder jetting additive manufacturing (BJ-AM) technology is a process by which a part is fabricated layer by layer through depositing liquid binder in the designated regions of each layer until the feature is complete. Due to the use of binder in geometry generation, this process possesses various advantages over the other additive manufacturing technologies including the ability to create colored objects via colored binders, lower cost, lack of heat-induced defects, and its potential capability to print a variety of materials such as metals, sands and ceramics. Although the application of the binder jetting process has been recently reported by different …

Incorporating Germanium Oxide Into The Glass Phase Of Novel Zinc/Magnesium-Based Gpcs Designed For Bone Void Filling: Evaluating Their Physical And Mechanical Properties, Basel A. Khader, Omar Rodriguez, Mark R. Towler

Chemical and Biochemical Engineering Faculty Research & Creative Works

The structural role of Germanium (Ge), when substituting for Zinc (Zn) up to 8 mol % in the 0.48SiO₂-0.12CaO-0.36ZnO-0.04MgO glass series, was investigated with respect to both the glass chemistry and also the properties of glass polyalkenoate cements (GPCs) manufactured from them. The Network connectivity (NC) of the glass was calculated to increase from 1.83 to 2.42 with the addition of GeO₂ (0-8 mol %). Differential thermal analysis (DTA) results confirmed an increase in the glass transition temperature (T_g) of the glass series with GeO₂ content. X-ray photoelectron spectroscopy (XPS) showed an increase in …

Breaking Down Traditional Classroom Walls And Studying Spacesuits Abroad, Ryan L. Kobrick, Jessica Mckee Ph.D., Sue A. Macchiarella, Angelica Gould

Publications

The spacesuit curriculum under development by the Spacesuit Utilization of Innovative Technology Laboratory (S.U.I.T. Lab) in the Spaceflight Operations program of the Applied Aviation Sciences Department at Embry-Riddle Aeronautical University has the unique challenge of educating non-engineering students about extremely technical space systems, highlighted by spacesuits. CSO 399: “Spacesuits and Human Spaceflight Operations” course, taught in Greece each summer, introduces students to human spaceflight topics. This unique offering takes advantage of the clear water visibility in the Aegean Sea with practical underwater demonstrations of space operations. Students live in confined quarters on a sailboat for two weeks to simulate operations …

Hexavalent Chromium Toxicity On Human Epithelial Cells And Protection By Ascorbic Acid And Epigallocatechin Gallate, Timmy Mayotte

Pence-Boyce STEM Student Scholarship

Hexavalent chromium or Cr(VI) is a known carcinogen in human beings, though the exact mechanism of carcinogenicity is still unknown. The same chemical compound is also found at varying levels in the water sources of more than 200 million Americans. While the government currently regulates total chromium levels, they have yet to determine a permissible exposure limit for Cr(VI). There is currently no method of preventative treatment for the chemical. The focus of this study was to determine the mechanism of carcinogenicity of Cr(VI) as well as confirm the viability of antioxidants as a preventative treatment. Because of Cr(VI)’s strong …

The Development Of A Temporomandibular Force Simulator To Study Craniofacial Strain In-Vitro, Kenneth Kc Ip

Electronic Thesis and Dissertation Repository

An in-vitro musculoskeletal loading simulator was developed to replicate the internal forces of mastication, and then employed in a comparison of clinically relevant facial fracture repairs. Muscle forces are simulated by pneumatic pistons via 3D printed mounts that are reverse-engineered from CT scan to match muscle attachment sites, which are adhered to bone in order to simulate native stress distributions. Bite force and bone strain pattern of the craniofacial structure under load were measured using a force sensor and strain gauges respectively. In a series of five fresh-frozen cadaveric heads, it was found that strain patterns of the craniofacial structure …

Distribution And Localization Of Novel Iodine Nanoparticles In The Human Glioma 1242 Growing In The Brains Of Mice, Benjamin Billings

Honors Scholar Theses

Observing and designing the in vivo distribution and localization of therapeutic nanoparticles is an essential aspect of developing and understanding novel nanoparticle- based medical treatments. This study investigates novel PEGylated Iodine-based nanoparticles (INPs), an alternate composition to the more widely researched gold nanoparticles (AuNPs), which may help avoid adverse effects associated with AuNPs, such as potential toxicity and skin discoloration, when used in similar applications. Determining the localization of the novel INPs within murine brains containing human glioma U-1242MG cells is critical in assisting the development of radiation dose enhancement therapy for this aggressive cancer. Radiation dose enhancement utilizes the …

Using Reproducing Kernel Particle Method For Shallow Water Problems, Chien-Ting Sun, On-Lei Annie Kwok, Pai-Chen Guan, Wen-Kai Shih

Journal of Marine Science and Technology

In this paper, a meshfree numerical scheme, which is based on the reproducing kernel particle method (RKPM), is proposed to solve the shallow water equations (SWEs). By applying the split coefficient matrix method on SWEs, RK approximation with upstream scheme can be employed for spatial discretization. Temporal discretization of SWEs is handled by the secondorder total-variation diminishing Runge-Kutta method. The merits of the present method are verified by performing three numerical experiments, which are problems related to open channel flow, oblique hydraulic jump and two-dimensional dam break. It is found that the proposed meshfree numerical scheme is able to efficiently …

Computational Music Biofeedback For Stress Relief, Jason Capili, Mark Hattori, Maile Naito

Computer Science and Engineering Senior Theses

The purpose of our project is to use EEG technology to combat stress in our daily lives. One of the most accessible EEG technologies that targets this challenge is the Muse headband, a wearable device that pairs with a phone application to help users train their brains to relax. The applications main goal is to help users train their brain to be more relaxed by monitoring and reporting their levels of stress. However, one of the shortcomings we noticed is that the constant notifications of how stressed we are actually adds to the level of stress as opposed to helping …

The Effect Of Implant Girth And Implant Collar On The Degree Of Bone To Implant Contact And Bone Stresses In The Proximal Humerus, Stephanie Synnott

Electronic Thesis and Dissertation Repository

Stem design is a crucial element for the success of shoulder prostheses. Various components of stem design have been investigated; however, little research has been conducted on the effects of (1) implant girth and (2) an implant collar on load transfer. A generic implant model was designed and employed in a (FE) model to determine 3 outcome measures: changes in the degree of bone to implant contact (BIC), changes in cortical and trabecular bone stresses from the intact state, and changes in cortical and trabecular strain energy densities (SED). The variables examined were (1) implant girth (small, medium [generic base …

Prediction Of Forelimb Muscle Activities And Movement Phases Using Corticospinal Signals In The Rat, Sinan Gok

Dissertations

The targeted population for this project is primarily patients with high level spinal cord injury (SCI) and individuals with motor neuron diseases (MND). In both SCI and MND cases motor control is interrupted due to lack of communication between the brain and the musculature, although both sides are otherwise functional. The approach in this project is to use neural engineering techniques to restore the motor function that was lost because of an injury or disease.

Brain-computer interfaces (BCIs) attempt to extract the volitional signals from the cortex when the brain's normal outputs to the musculoskeletal system are impaired. However, BCIs …

Recent Developments In Tough Hydrogels For Biomedical Applications, Yuan Liu, Weilue He, Zhongtian Zhang, Bruce P. Lee

Department of Biomedical Engineering Publications

A hydrogel is a three-dimensional polymer network with high water content and has been attractive for many biomedical applications due to its excellent biocompatibility. However, classic hydrogels are mechanically weak and unsuitable for most physiological load-bearing situations. Thus, the development of tough hydrogels used in the biomedical field becomes critical. This work reviews various strategies to fabricate tough hydrogels with the introduction of non-covalent bonds and the construction of stretchable polymer networks and interpenetrated networks, such as the so-called double-network hydrogel. Additionally, the design of tough hydrogels for tissue adhesive, tissue engineering, and soft actuators is reviewed.

Research And Development Of Powder Brazing Filler Metals For Diamond Tools: A Review, Fei Long, Peng He, Dusan P. Sekulic

Mechanical Engineering Faculty Publications

Powder brazing filler metals (PBFMs) feature a number of comparative advantages. Among others, these include a low energy consumption, an accurate dosage, a good brazeability, a short production time, and a high production efficiency. These filler metals have been used in the aerospace, automobile, and electric appliances industries. The PBFMs are especially suitable for diamond tools bonding, which involves complex workpiece shapes and requires accurate dosage. The recent research of PBFMs for diamond tools is reviewed in this paper. The current applications are discussed. The CuSnTi and Ni-Cr-based PBFMs have been the two commonly used monolayer PBFMs. Thus, the bonding …

Maintaining And Controlling An Extrinsic Biofilm For Pathogen Removal In Dental Unit Water Lines, Bilal B. Al-Bataina

Electronic Thesis and Dissertation Repository

The control of biofilm formation is a major concern for industrial, environmental, and public health. Undesirable biofilms can harbor different disease-causing pathogens and shorten the operational life of different equipment. On the other hand, beneficial biofilms are also used in various applications and managing its growth and activity can be desirable. Killing the biofilm does not usually incorporate the removal of the dead biofilm structure that is adhered to the surface. Therefore, the aim of this thesis is to control biofilm formation; to be able to remove, inhibit, and enhance biofilm formation. This thesis investigated the use of norspermidine, D-amino …