Biomedical Engineering and Bioengineering Commons^™

Development Of An Adhesive Emulsion Hydrogel For Soft Tissue Reconstruction, David J. Alpert

Dissertations and Theses

Soft tissue filling materials are most commonly associated with various aesthetic, cosmetic procedures, primarily using lightly cross-linked hyaluronic acid to fill wrinkles and give facial features a more youthful appearance. These natural materials are biocompatible but degrade over time while more persistent synthetic fillers may provoke a chronic inflammatory response. Migration from the injection site is also a key factor as this may not only render the implant non- functional but necessitate further procedures for removal of the foreign material. Such concerns are more pronounced for soft tissue reconstruction procedures (e.g., to treat congenital defects or traumatic injuries), which require …

The Study Of Knee And Ankle Sagittal Plane Angles For On-Court Versus Off-Court Cutting, Alexi Rebecca Hempe

Dissertations and Theses

Lower extremity injuries are common among basketball athletes. Majority of these injuries are non-contact and therefore preventable. While previous research has explored high-risk movements associated with lower extremity injuries, limited research has explored the influence of settings for these movement patterns, particularly on a basketball court. This study aims to examine the knee and ankle joint angles in the sagittal plane of a 90-degree cut for on-court versus off court. Thirteen (13) subjects, four males (19.5 ± 1.0 years of age; 198.8 ± 4.8 cm of height; 198.8 ± 13.8 lbs. of weight) and nine females (19.8 ± 1.5 years …

Design And Validation Of A Multiple Axis, Passive 3d-Printed Ankle-Foot Prosthetic For Functional Gait, Brogan Rene Landeen

Dissertations and Theses

By 2050, an estimated 3.6 million individuals will be living with lower limb loss, with transtibial (below the knee) amputations being the most common type of lower limb surgery. Prosthetic devices are the standard of care for rehabilitating these amputees; each device is explicitly designed to enhance stability, energy storage and release, flexibility, and active propulsion. Prosthetic selection is based on user specifications, including activity level, comfort, and anthropometry. Despite the consensus that prosthetics help to restore impaired gait, traditional, commercial prosthetics fabricated with carbon fiber via injection molding are expensive and often require multiple modifications by a prosthetist before …

Multimodal Imaging Of Protein-Based Biomaterials For Delivering Chemo-Agent Cargo For Glioblastoma Treatment In A Murine Model, Orin Mishkit

Dissertations and Theses

Protein-based self-assembling biomaterials, known as Thermo-Responsive Assembled Proteins (TRAP), present meaningful potential as drug delivery carriers. These materials enable the controlled, slow release of poorly soluble chemotherapeutic agents, such as doxorubicin (Dox), while potentially reducing systemic off-target effects. In collaboration with multiple NYU labs, this study evaluated the efficacy of two TRAP variants—TRAP and F-TRAP—as drug delivery carriers in a xenograft mouse model of glioblastoma multiforme (GBM).

The primary objective was to compare the effectiveness of TRAP-loaded Dox (TRAP-DOX) to free Dox in achieving tumor extravasation and accumulation, facilitating sustained drug release. We hypothesized that the leaky vasculature of GBM …

Adaptation Of The Biodent For Spherical Microindentation To Determine Elastic Modulus In Small Rodent Bones, Mixame E. Jerome

Dissertations and Theses

Mechanical and material properties of bone are essential for understanding both normal skeletal function and the progression of bone-related diseases. Microindentation has become a widely used method for evaluating tissue mechanical properties of bone, as it samples the contributions of microarchitecture and composition. Microindentation using a standard pointed tip inherently introduces both elastic and plastic deformation into the material. In contrast, indentation with a spherical tip can be operated entirely in the elastic range, providing for a non-damaging test that has significant advantages over sharp indentation techniques. Moreover, a key advantage of using spherical indentation lies in its operation under …

Explorations Of Dna-Single-Walled Carbon Nanotube Interactions To Develop Multiplexed Molecularly Specific Biosensors For Inflammation, Amelia K. Ryan

Dissertations and Theses

Inflammatory cytokines such as interleukin-6 (IL-6) and interleukin-12 (IL-12) are central regulators of immune signaling and key biomarkers of disease, yet existing assays for their detection remain slow, invasive, and lack multiplexing ability. This dissertation advances the development of single-walled carbon nanotube (SWCNT) optical nanosensors capable of real-time, multiplexed, and molecularly specific cytokine detection through innovative use of single-stranded DNA (ssDNA) interfaces.

First, an IL-6-specific DNA aptamer was employed as both a dispersing agent and recognition probe for SWCNT fluorescence sensing. Sequence modifications, including anchor domains, truncations, and thermally induced refolding, were systematically tested to optimize sensitivity and selectivity. The …

Advancing Electrical Stimulation: Full-Head Mri Segmentation For Abnormal Brain Anatomy With Tdcs, Andrew Birnbaum

Dissertations and Theses

Evaluating the effectiveness of transcranial direct current stimulation (tDCS) is essential for guiding its integration into therapeutic and performance-enhancement applications. In our laboratory, we investigate the efficacy of tDCS across multiple experimental models, including both animal and human studies. I have contributed significantly to the execution and analysis of these experiments, which include studies in rats and healthy human participants aimed at evaluating whether electrical stimulation of the motor cortex can enhance motor learning. These studies assess improvements in fine motor performance resulting from tDCS. In stroke patients, I contribute to our investigation of tDCS as a rehabilitative intervention, particularly …

Wearable Disposable Elecetrotherapy, Mohamad Fallahrad

Dissertations and Theses

Non-invasive electrotherapies offer promising treatments for a wide range of conditions such as pain, headaches, depression, addiction, cognitive decline, wound healing, and drug delivery. However, patient compliance remains low due to the high initial cost, cumbersomeness and inconvenience of existing technology compared to pharmaceuticals. Current electrotherapy devices are often bulky and require users to connect disposable electrodes, initiate programs, and manage charging cycles, which hinders widespread adoption.

We address these challenges by designing and validating a novel electrotherapy platform that is single-use, disposable, low-cost, and wearable. Activated automatically upon skin contact, the device delivers a preset dose of controlled electrical …

Characterization Of The Intrinsic Neural Timescale Indices As A Reliable Fingerprint Of Brain Dynamics, Helya Honarpisheh

Dissertations and Theses

Intrinsic neural timescales (INTs) characterize the persistence of neural activity over time and offer insight into the brain’s temporal hierarchy. This thesis evaluates and compares six autocorrelation-based INT metrics—AR(1) Coefficient (Autoregressive Coefficient at 1), First Zero Lag, Lag at ACF = 1/e, Sum of Positive ACFs, ACF at Half Lag, Exponential Decay Constant (τ)— using resting-state fMRI data from 400 cortical regions across a large, lifespan sample (ages 6– 85) from the NKI-Rockland dataset. A discriminability analysis revealed that the AR(1) coefficient provided the highest test-retest reliability and individual specificity across repeated scans, establishing it as the most reliable INT …

Generation And Characterization Of Human Blood-Brain Barrier Models For Investigating Neuropsychiatric Disorders And Tumor Metastasis, Yunfei Li

Dissertations and Theses

The blood–brain barrier (BBB) is important in the normal function of the central nervous system (CNS). An altered BBB has been described in various neuropsychiatric disorders. The brain-specific microvascular endothelial cell (BMEC) is an essential structural component of the BBB. To test if integrity of the BBB formed by BMECs is compromised in 22q11.2 deletion syndrome (also called DiGeorge syndrome), which is one of the validated genetic risk factors for schizophrenia, a 2D iBBB (induced BBB) on a Transwell filter was generated from human microvascular endothelial cells (HBMECs) derived from the induced pluripotent stem cells (iPSCs) out of patients with …

Your Foot Is Not A Brick: Using A Multi-Segment Foot Model To Explore The Actions Of The Ankle-Foot Complex During Uneven Terrain Gait., Tayler Jon Hoekstra

Dissertations and Theses

The field of biomechanics has seen continued development of models to be used and circumstances to be considered. An increasing number of more complex models for the foot known as multi-segment foot models (MSFMs) have created opportunities to better understand the compensatory motion of this vital portion of human anatomy. This research seeks to utilize one such MSFM model to increase understanding in how human ambulation changes in uneven terrain environments. Unique inner-foot joints defined by the Rizzoli foot model (RFM) were measured for and compared for subjects traversing both even and uneven terrain to quantify joints that experienced significant …

Pcl And Dmso2 Composites As Biomaterials For Additive Manufacturing, Jae-Won Jang

Dissertations and Theses

Tissue engineering provides a viable solution to address the shortage of organ donors for allograft transplants. Its primary objective is the replacement or regeneration of damaged tissues which is developed by combining living cells, a scaffold, and a bioreactor. Among these components, the scaffold serves as an artificial extracellular matrix (ECM), which plays a pivotal role in supporting cell adhesion, proliferation, differentiation, and overall tissue development. Additive manufacturing (AM), commonly referred to as three-dimensional (3D) printing, emerges as a promising method for scaffold fabrication due to its capability to create complex and repeatable geometries.

Polycaprolactone (PCL) has been one of …

The Effects Of Bilateral Stimulation On Motor Learning, Shania Rehmudin

Dissertations and Theses

Motor learning is a set of complex processes aimed at learning and refining new skills by practicing them. There are three proposed stages of motor learning: cognitive, associative, and autonomous. While all stages are crucial, research suggests that the cognitive stage holds particular significance, laying the foundational groundwork for effective skill acquisition. Although research has explored many innovative ways to facilitate motor memory, to our knowledge, none has explored the optimization of motor skill learning through manipulating the focus of attention using bilateral stimulation. Therefore, this study explored the effects of bilateral stimulation on squat skill acquisition. Nineteen (19) subjects, …

Mivt: Medical-Informed Vision Transformer For Early Epilepsy Diagnosis, Md Masum Rana

Dissertations and Theses

Epilepsy is a neurological disorder characterized by recurrent, unprovoked seizures, and early diagnosis is crucial for effective management and treatment. However, the diagnosis of epilepsy, particularly in its early stages, remains challenging due to the subtle nature of seizures and the complexity of brain activity patterns. In this research, we introduce the Medical-Informed Vision Transformer (MIVT), a deep learning architecture specifically designed to improve early epilepsy diagnosis from multimodal neuroimaging data. Our model integrates insights from both medical knowledge and state-of-the-art Vision Transformers (ViTs) to enhance the accuracy and interpretability of seizure detection and localization. The MIVT leverages the rich …

Balloon Model For Water Vapor Ablation Of Non-Muscular Invasive Bladder Cancer Cells, Jennifer Mussell

Dissertations and Theses

Bladder cancer has a considerable issue with multiple recurrences of tumors, and current treatments are unable to adequately address these concerns. This results in continuous surveillance. Ablation, or killing, of bladder cancer cells is often incomplete and results in a high probability of recurrence. This paper aims to evaluate a potential method of ablation using a model that simulates a bladder and what conditions are needed for optimal quality and depth penetration. This balloon model for water vapor ablation is intended to simulate bladder cancer cells and determine if this is a viable avenue for future research. A device from …

Development Of A Modular Lab Automation System With Applications To Animal And Bacteria Cell Culture, Timothy William Hartman

Dissertations and Theses

The challenges faced while executing wet lab protocols encourage the development of automation systems to come alongside human scientists. Today’s cutting-edge experiments involve complex protocols with precise measurements usually performed manually. Even simpler biological protocols can be tedious and prone to error, as was seen during the COVID-19 pandemic and society’s demand for high-volume, rapid sample analysis. Moreover, reproducibility suffers when there is excessive variability and insufficient data. Here, we leveraged the Stanford Biodesign process to develop a modular lab automation system and image analysis workflow to address challenges like these. This flagship automation platform at The University of South …

An Optical Aptamer-Based Carbon Nanosensor For Cortisol Detection, Jessica Kretli Zanetti

Dissertations and Theses

Cortisol is a hormone related to numerous biological functions. This hormone is primarily associated with regulating the body’s stress response, including its effects on metabolism, immune function, and energy balance. Additionally, it plays a critical role in maintaining physiological homeostasis during periods of physical or psychological stress. Consequently, it is critical to monitor levels of this hormone to understand different vital processes it can impact. This work presents the development of an optical aptamer-based carbon nanosensor for the detection of cortisol. The sensor utilizes single-walled carbon nanotubes (SWCNTs) functionalized with a specific DNA aptamer to achieve high specificity and sensitivity. …

Using Mechanical Interventions To Enhance Drug Transport To Bone Tumors, Michelle Gelbs

Dissertations and Theses

Bone metastasis occurs when cancer cells spread from a primary site to a secondary location in bone. Current treatments for metastatic bone tumors typically involve systemic chemotherapy, bisphosphonates, radiotherapy, or surgery; however, due to morphological changes in the tumor microenvironment and elevated interstitial fluid pressure, tissue penetration of therapeutic agents is often more limited in cancerous tumors compared to normal tissue. Weight-bearing mechanical loading applied to bone, as well as other mechanical stimulations such as vibration, have been shown to cause loading-induced bone deformations that increase convective transport via interstitial fluid flow. We hypothesize that mechanical loading can increase the …

Optimizing Transcranial Focused Ultrasound: Calibration, Neuro Navigation, And Bold Fmri Evidence Of Neuromodulation, Amilcar J. Malave

Dissertations and Theses

This thesis presents the development, calibration, and initial implementation of transcranial focused ultrasound (tFUS) for neuromodulation in a human study. The primary objectives were to design a system capable of delivering precise and safe ultrasound stimulation to targeted brain regions and to conduct preliminary trials to assess its effects on brain activity. A custom calibration device was developed to ensure accurate measurement of acoustic pressure, addressing challenges such as voltage alterations caused by changes in system impedance. Additionally, a neuro-navigation tool was created to facilitate precise targeting of the right subgenual anterior cingulate cortex (right sgACC), enabling accurate placement of …

Modulation Of Motor Learning With High-Intensity Transcranial Electric Stimulation, Gavin Hsu

Dissertations and Theses

Research thus far on noninvasive, transcranial electric stimulation have produced mixed results from in vivo human experiments. This work tests the hypothesis that applying higher stimulation intensities would induce intracranial electric fields that more closely match the higher magnitudes used in animal and in vitro studies and subsequently yield more robust effects. As done commonly in the literature, we targeted the motor cortex (M1), specifically in the context of neuroplastic changes taking place during motor learning in healthy adult humans. This work also seeks a better understanding of the neural correlates underlying motor skill learning.

Through multiple large-sample studies, this …

Mechanisms For Regenerative Intervertebral Disc Healing During Early Growth In Mice, Danielle N. D'Erminio

Dissertations and Theses

Annulus Fibrosus (AF) defects of intervertebral discs (IVDs) cause painful disability, for example when herniated tissue compresses against adjacent nerves. Discectomy, the current standard of treatment to address herniation, does not repair AF defects and can result in re-herniation and recurrent pain. As such there is a need for improved AF repair strategies. It has previously been established that neonatal mice functionally regenerate following severe AF injury providing a model of successful innate AF repair processes that contrasts the poor healing of adult mice. This dissertation focuses on identifying mechanisms of AF regenerative healing in neonatal mice subjected to severe …

Data-Driven Biomedicine Investigation Of Genetic And Infectious-Based Diseases Using Omics Data And Data Science Methodologies., Diing Agany

Dissertations and Theses

The binary model of existence consists of health and disease, with health being complete physical, mental, and social well-being and disease being a pathological process. Humanity has been plagued by genetic and infectious diseases since civilization's dawn. These diseases cause changes in this model at the system biology level. Omics technologies, data science methodologies, and big data are being used to study these changes at the molecular level, leveraging biological processes' interconnectedness. Also, advanced computational methodologies are essential for efficient analytics and actionable discovery. In this dissertation, genetic and infectious-based diseases are investigated using omics data and data science methods …

Data-Driven Biomedicine Investigation Of Genetic And Infectious-Based Diseases Using Omics Data And Data Science Methodologies., Diing De Mapior Agany

Dissertations and Theses

The binary model of existence consists of health and disease, with health being complete physical, mental, and social well-being and disease being a pathological process. Humanity has been plagued by genetic and infectious diseases since civilization's dawn. These diseases cause changes in this model at the system biology level. Omics technologies, data science methodologies, and big data are being used to study these changes at the molecular level, leveraging biological processes' interconnectedness. Also, advanced computational methodologies are essential for efficient analytics and actionable discovery. In this dissertation, genetic and infectious-based diseases are investigated using omics data and data science methods …

Measurement Of Fluid Movement Throughout The Brain Via Multiple Magnetic Resonance Imaging Techniques During High-Definition Transcranial Direct Current Stimulation, Jack W. Beaty Mr

Dissertations and Theses

Transcranial Direct Current Stimulation (tDCS) is a non-invasive method of neuromodulation with applications in neuroscience, clinical care, and biomedical engineering. tDCS has been well established as a safe method of applying low amplitude current between two or more electrodes to alter excitation thresholds and neuroplasticity. Recently, in-vitro and clinical studies have suggested that DC stimulation can induce a transient, polarity-specific, effect of increased water exchange across the blood-brain barrier (BBB). The electroosmotic effect, the proposed phenomenon driving water exchange, is a biophysical response of charged ions moving across an oppositely-charged surface, i.e., the tight junction, when subjected to an electric …

Assessment Of Material Properties In Bone Surrounding Microdamage, Niovi Dollas

Dissertations and Theses

Bisphosphonates [BPs] are the mainstay for osteoporosis treatment. They suppress bone resorption/remodeling, preventing bone loss. However, BPs also suppress the beneficial bone remodeling that replaces microscopically damaged bone that occurs from normal mechanical wear-and-tear or fatigue, leading to impaired tissue material properties and in some instances atypical femoral fractures.

In these studies, we assessed the effects of acute fatigue, fatigue induced remodeling, and fatigue microdamage with remodeling suppression using the clinical BP, alendronate [ALN], on local bone material properties. Studies were performed on cortical bone sections from rat ulnae into which fatigue damage had been introduced in vivo. Rat …

Use Of Bioheat Modeling To Characterize And Optimize Implantable Medical Devices And Neuromodulation Technologies, Adantchede Louis Zannou

Dissertations and Theses

Medical device development includes prototyping, benchtop characterization, preclinical studies, and clinical trials. Understanding the limitations and potential adverse effects of medical devices prior to their administration in humans is a crucial first step. Optimizing medical devices is essential to employing technology and improving patients care. Computational modeling is widely adopted as a powerful tool to predict stimulation/recording parameter optimization, rapid electrode/device prototyping, investigating novel mechanism of action, and testing working principles of any medical devices. Many implantable neuromodulation technologies including Spinal Cord Stimulation (SCS), which provide substantial therapeutic benefit for patient population with lower back pain, produces heat via the …

Tdcs Effects On Synaptic Plasticity And Motor Skill Learning, Forouzan Vasheghani Farahani

Dissertations and Theses

Transcranial direct current stimulation (tDCS) is a non-invasive brain stimulation technique that involves the application of low-intensity constant current to the brain through electrodes placed on the scalp. Its potential to enhance brain function and treat brain-related disorders has led to its increasing popularity due to its safety, simplicity, and affordability. However, its effectiveness remains a topic of debate.

Mechanically Driven In Vivo Osteocyte Ca2+ Signaling: Aging And Pharmacologic Effects, James Padgett

Dissertations and Theses

Bone’s ability to respond and adapt to mechanical loading declines significantly with age which is a major contributor to bone fragility. It is widely accepted that osteocytes are the key cells responsible for orchestrating the development of the “ideal” skeleton. This ability is attributed to osteocyte’s role as the primary mechanosensing cell that is responsible for maintaining the skeleton’s integrity throughout life. Recent work from our laboratory has shed light into how osteocytes respond to mechanical loading in vivo. The breakthrough approaches that enabled these discoveries were development of: (1) the first ever reporter mouse model with a genetically encoded …

Optimization Of Optical Nanosensor Response For The Detection Of Anthracyclines Using A Binary Machine Learning Classifier, Myesha Thahsin

Dissertations and Theses

Pharmacokinetic variables such as interindividual variation in metabolizing and eliminating drugs makes dose selection of chemotherapeutic anthracyclines difficult. One potential solution to determining dosing levels of an anthracycline is the development of non-invasive sensors to monitor their pharmacology in vivo. Single-walled carbon nanotubes (SWCNT) have substantial potential for in vivo sensor development, as they exhibit near-infrared fluorescence in the tissue-transparent window and a robust response to their local environment. An emerging method for evaluating and optimizing SWCNT sensor response is through machine learning. In this study, anthracyclines Daunorubicin, Doxorubicin, Epirubicin, Mitoxantrone and Idarubicin, were used to interrogate 12 SWCNT preparations …

Ultra-High Field Mri Methods For Precise Anatomical And Spectroscopic Measurements In The Brain And Application To Neurological And Neuropsychiatric Diseases, Judy Alper

Dissertations and Theses

Neurological and neuropsychiatric diseases and disorders are a major burden on society, impairing the health and functioning of millions of people every year. There is a need to define the biological bases of these diseases and identify potential biomarkers to improve diagnosis, monitoring, and treatment efficacy across multiple diseases.

Magnetic resonance imaging (MRI) is a noninvasive imaging technique which facilitates detection of brain lesions and visualization of the brain overall. However, limitations in contrast and resolution at clinical field strengths may hinder investigation of the underlying biological mechanisms of these diseases. Ultra-high field MRI scanners, such as those at 7-Tesla, …