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Full-Text Articles in Engineering
Understanding The Mechanisms By Which Cable Sway Produces Motion Artifact In Mobile Electroencephalography, David Rojas
Understanding The Mechanisms By Which Cable Sway Produces Motion Artifact In Mobile Electroencephalography, David Rojas
Electronic Theses and Dissertations, 2020-
Mobile brain/body imaging utilizes electroencephalography (EEG) to record brain activity during human walking in dynamic environments. Motion artifact from cable sway affects the quality of EEG signals collected from the scalp, masking contributions of synchronously firing neurons. Previous studies have explored cable sway-induced motion artifact, but only during vigorous exercise or controlled sinusoidal motion. Therefore, a need remains to further understand the underlying mechanisms of this artifact, as it may help with developing real-time mitigation methods, reducing reliance on offline signal processing. In this thesis, I aimed to show that controlled cable sway could produce specific motion artifact waveforms in …
Gait Strategies While Walking With Discrete Perturbations On A Self-Paced Treadmill, Cesar Castano
Gait Strategies While Walking With Discrete Perturbations On A Self-Paced Treadmill, Cesar Castano
Electronic Theses and Dissertations, 2020-
Introducing perturbations on a self-paced treadmill allows participants to experience uncertain environments without restricting their ability to continuously change their walking speed and kinematics. In this dissertation, I evaluated how different self-paced treadmill controller sensitivities affected gait parameters and variability on decline, level, and incline slopes. I also investigated how healthy young and older adults adjust their gait strategies when responding to perturbations of varying unpredictability and whether the changes in gait strategies remained once the perturbations were no longer present. Lastly, I evaluated how differences in gait kinematics when responding to visual and mechanical perturbations at varying frequencies. I …
Probing Endothelial Cell Mechanics Under Disturbed Fluid Flow, Jingwen Wu
Probing Endothelial Cell Mechanics Under Disturbed Fluid Flow, Jingwen Wu
Electronic Theses and Dissertations, 2020-
Endothelial cells, which form the inner layer of the vasculature, interact with the extracellular matrix (ECM) by exerting mechanical contractile cell-substrate stress called tractions and cell-cell stresses called intercellular stresses. This cellular mechanical behavior involves many fundamental biological processes, including cell migration, differentiation, angiogenesis, and wound healing. Also, the inner surface of the vasculature, where endothelial cells reside, is constantly exposed to various fluid flows. The most variable fluid flow regimes occur primarily within branching regions of the vasculature. Endothelial cells residing within these regions experience disturbed flow, which consists of irregular flow patterns and extreme wall shear stress gradients. …
Electrode Evaluation And Electrocortical Dynamics Of Adapting To Small Perturbations During Treadmill Walking, Jinfeng Li
Electronic Theses and Dissertations, 2020-
Mobile brain-body imaging (MoBI) seeks to understand human brain and body dynamics during movement and locomotor tasks such as walking with perturbations that challenge balance and lead to adaptation of walking behavior. In this dissertation, I evaluated the long-term electromyography (EMG) recording performance of dry epidermal electrodes for measuring electrical muscle activity. I also evaluated the relationships between the signals recorded from the two sides of dual-sided electroencephalography (EEG) electrodes, a recent advancement in EEG electrode design for measuring electrical brain activity. Last, I investigated adaptation of brain and body responses to small and frequent perturbations during treadmill walking while …
A Measurement System For Detection Of Intestinal Motility In Neonates By Monitoring Slow Wave Activity, Garett Goodale
A Measurement System For Detection Of Intestinal Motility In Neonates By Monitoring Slow Wave Activity, Garett Goodale
Electronic Theses and Dissertations, 2020-
Similar to how electrocardiographic waves are the pace making signals of the heart, slow waves are the pace making signals of the intestines. Slow waves are electrical signals in the intestines that determine the speed at which food can move through the intestine ensuring proper digestion and uptake of nutrients. It has been shown that slow waves can be measured in adults using non-invasive, surface electrodes. However, no study has investigated the measurements of slow waves in neonates, specifically pre-term neonates. Around 7% of pre-term neonates suffer from necrotizing enterocolitis (NEC) which is a condition that causes damage to the …
Reporter Chondrocyte Optimization Of Bioinks For Zonal 3d Bioprinting Of Cartilage, Kari Martyniak
Reporter Chondrocyte Optimization Of Bioinks For Zonal 3d Bioprinting Of Cartilage, Kari Martyniak
Electronic Theses and Dissertations, 2020-
Osteoarthritis (OA) is the most common form of arthritis, often thought of as a disease of the elderly, but post traumatic OA predominantly impacts younger individuals. Articular cartilage is the tissue that coats the end of your bones in synovial joints. Since cartilage has limited healing capacity, defects, or injuries to it progressively erodes down to the subchondral bone. Unfortunately, current treatment options all have limitations, particularly for younger patients. Cartilage has a specific zonal architecture that is distinguished by the different cell morphologies and arrangements, biochemical composition, and mechanical properties. 3D bioprinting is a tissue engineering technique that involves …
The Role Of Pro-Longevity Micrornas In Aging, Sarah Noureddine
The Role Of Pro-Longevity Micrornas In Aging, Sarah Noureddine
Electronic Theses and Dissertations, 2020-
Cellular senescence, a hallmark of aging, has been implicated in the pathogenesis of many major age-related disorders, including atherosclerosis, metabolic disease, and neurodegenerative disorders such as Alzheimer's disease (AD). AD is characterized by increased cognitive impairment and treatment options available provide minimal disease attenuation. Additionally, diagnostic methods for AD are not conclusive with definitive diagnoses requiring postmortem brain evaluations. Therefore, miRNAs, a class of small, non-coding RNAs, have garnered attention for their ability to regulate a variety of mRNAs and their potential to serve as both therapeutic targets and biomarkers of disease. Several miRNAs have already been implicated with AD …
Characterization Of A Malachite Green Dna Aptamer And Development Of Malachite Green Dna Aptamer Sensor, Martin O'Steen
Characterization Of A Malachite Green Dna Aptamer And Development Of Malachite Green Dna Aptamer Sensor, Martin O'Steen
Electronic Theses and Dissertations, 2020-
Hydrogels have been extensively studied for use in applications such as tissue engineering, drug delivery systems, wound dressing, actuators, valves, and sensors in Micromechanical Systems (MEMS), among others. Thermo-responsive hydrogels in particular pose various advantages such as their capability to respond to an external stimulus and reverse the response when the stimulus is removed and the ability to imbibe a significant amount of solvent and increase their volume by over 1000%. Extensive research has been conducted to tune and improve hydrogel's rate and degree of swelling and mechanical properties. Previous work showed that when synthetic clay (Laponite) is cross-linked with …
Tailoring Of The Left Ventricular Assist Device Cannula Implantation Using Coupled Multi-Scale Multi-Objective Patient Specific Optimization., Abubakar Dankano
Tailoring Of The Left Ventricular Assist Device Cannula Implantation Using Coupled Multi-Scale Multi-Objective Patient Specific Optimization., Abubakar Dankano
Electronic Theses and Dissertations, 2020-
Despite advancements in device design and anti-coagulation treatments, there are numerous adverse events that may occur following implantation of LVADs. The most devastating involves the embolization of thrombus into the brain causing a stroke, with incidence of up to 14-47% over a 6–12-month period. This study aims to elucidate ways to reduce this risk by surgical maneuvers guided by a multi-scale computational fluid dynamics analysis wrapped around a multi-objective shape optimization scheme which optimizes the anastomosis location of the VAD outflow graft (OG) along the ascending aorta to minimize the incidence of thrombi reaching the cerebral vessels and reduce particle …
Design Of Miniaturized Antipodal Vivaldi Antennas And A Microwave Head Imaging System For The Detection Of Blood Clots In The Brain, Farhana Parveen
Design Of Miniaturized Antipodal Vivaldi Antennas And A Microwave Head Imaging System For The Detection Of Blood Clots In The Brain, Farhana Parveen
Electronic Theses and Dissertations, 2020-
Traditional brain imaging modalities, for example, MRI, CT scan, X-ray, etc. can provide precise and high-resolution images of the brain for diagnosing lesions, tumors or clots inside the brain. However, these modalities require bulky and expensive test setups accessible only at specialized diagnostic centers, and hence may not be suitable or affordable to many patients. Furthermore, the inherent health risks limit the usability of these modalities for frequent monitoring. Microwave imaging is deemed a promising alternative due to its being cost-effective, portable, non-ionizing, non-intrusive. Therefore, this work aims to design an effective microwave head imaging system for the detection of …
Understanding Forearm Muscle Coordination In Children, Miguel Gonzalez
Understanding Forearm Muscle Coordination In Children, Miguel Gonzalez
Electronic Theses and Dissertations, 2020-
A combination of surface electromyography (EMG) and pattern recognition algorithms have led to improvements in the functionality of upper limb prosthetics. This method of control relies on user's ability to repeatedly generate consistent muscle contractions. Research in EMG based control of prosthesis has mainly utilized adult subjects who have fully developed neuromuscular control. Little is known about children's ability to generate consistent EMG signals necessary to control artificial limbs with multiple degrees of freedom. To address this gap, two experiments were designed to validate and benchmark an experimental protocol that quantifies the ability to coordinate forearm muscle contractions in able-bodied …