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Full-Text Articles in Engineering

The Contribution Of Micrornas To Rybp Silencing In Glioblastoma Multiforme, Alex B. Lee May 2024

The Contribution Of Micrornas To Rybp Silencing In Glioblastoma Multiforme, Alex B. Lee

Graduate Theses

Glioblastoma multiforme (GBM) is a highly aggressive and invasive tumor of the central nervous system (CNS). Survival rates are abysmal, with only 7.2% of patients alive 5-years after diagnosis. Because of this, understanding epigenetic alterations that give GBM tumors their aggressive phenotypes is critical for the development of more targeted and effective therapies. These alterations frequently affect a group of proteins called the Polycomb group proteins, which play important oncogenic and tumor suppressive roles in cancer. One Polycomb protein, the RING1- and YY1-binding protein (RYBP), is downregulated in a majority of GBM patients, suggesting a strong tumor suppressive property. In …


Selective Transfection Of A Transferrin Receptor-Expressing Cell Line With Dna-Lipid Nanoparticles And Synthesis Of Parasite-Derived Glycans As Biomarkers For Leishmaniasis, Irodiel Vinales Lozano May 2024

Selective Transfection Of A Transferrin Receptor-Expressing Cell Line With Dna-Lipid Nanoparticles And Synthesis Of Parasite-Derived Glycans As Biomarkers For Leishmaniasis, Irodiel Vinales Lozano

Open Access Theses & Dissertations

Despite notable progress in lipid nanoparticle (LNP)-mediated gene delivery, achieving selective transfection of specific cell types, such as cancer cells, remains a significant hurdle, hindering the advancement of innovative gene therapies. In this study, we engineered an LNP formulation encapsulating plasmid DNA (pDNA) encoding the monomeric Green Lantern (mGL) fluorescent reporter protein. The DT7 peptide ligand targeting human transferrin receptor 1 (hTfR1) was also conjugated to the LNP surface for targeted delivery to hTfR1-expressing cells. Optimization of LNP composition yielded favorable particle diameter, ζ-potential, yield, and pDNA encapsulation efficiency. Evaluation of transfection selectivity using a panel of two engineered cell …


Selective Targeting Of Microglia By Quantum Dots And Green Synthesis Of Metal Organic Biohybrids; Applications In Dynamic Cell And Assay Systems, Navya Uppu Mar 2024

Selective Targeting Of Microglia By Quantum Dots And Green Synthesis Of Metal Organic Biohybrids; Applications In Dynamic Cell And Assay Systems, Navya Uppu

Doctoral Dissertations

Neurological disorders are the leading cause of physical and cognitive disability across the globe, currently affecting approximately 15% of the worldwide population. Part of the glioma microenvironment are microglia, resident immune cells of the CNS that were thought to be involved in the pathogenesis of diverse neurodegenerative diseases. Though it remains uncertain what triggers microglial activation in these disorders, targeting and tracking microglial functions using nanotools like Quantum Dots (QDs) could help us elucidate them in such neurological diseases. This research focuses on the comparative study of different QDs formulations and their selective uptake by brain microglia in primary cultures …


Degradable Staples And Delivery Device, Meha Elango, Jessica Cabrera, Makayla Scarpitti, Kareemat Melaiye Jan 2024

Degradable Staples And Delivery Device, Meha Elango, Jessica Cabrera, Makayla Scarpitti, Kareemat Melaiye

Williams Honors College, Honors Research Projects

The scope of this project is to design a method to secure skin grafts to healthy tissue. The ultimate goal for the proposed method is to be dissolvable in some form. Currently, skin grafts procedures utilize staples in most cases to hold a skin graft in place, but there are disadvantages that come with it. Staples are easy to place, but time consuming during the removal procedure. They also cause a lot of pain and discomfort for the patient. The goal of this project is to determine a way a secure skin grafts to healthy skin in order to reduce …


Using Noninvasive Calibrated Cuff Plethysmography To Observe The Effects Of Cold-Water Immersion On Arterial Compliance, Rita M. Grigorian Dec 2023

Using Noninvasive Calibrated Cuff Plethysmography To Observe The Effects Of Cold-Water Immersion On Arterial Compliance, Rita M. Grigorian

Biomedical Engineering: Graduate Reports and Projects

As the prevalence of cardiovascular diseases continues to exponentially grow in populations across the globe, the necessity of determining underlying factors, effective methods of diagnoses, and universally available preventive measures also grows. Early detection of endothelial dysfunction, a proven precursor of cardiovascular diseases, can be extremely impactful in encouraging preventative measures and early intervention before medical conditions become chronic. In recent years, ice plunging, a form of cryotherapy involving full body immersion in cold water, has gained popularity within circles of fitness and health practitioners, gaining the interest of people of all backgrounds. Certain parallels observed between the human physiological …


Using Noninvasive Calibrated Cuff Plethysmography To Observe The Effects Of Cold-Water Immersion On Arterial Compliance, Rita M. Grigorian Oct 2023

Using Noninvasive Calibrated Cuff Plethysmography To Observe The Effects Of Cold-Water Immersion On Arterial Compliance, Rita M. Grigorian

Master's Theses

As the prevalence of cardiovascular diseases continues to exponentially grow in populations across the globe, the necessity of determining underlying factors, effective methods of diagnoses, and universally available preventive measures also grows. Early detection of endothelial dysfunction, a proven precursor of cardiovascular diseases, can be extremely impactful in encouraging preventative measures and early intervention before medical conditions become chronic. In recent years, ice plunging, a form of cryotherapy involving full body immersion in cold water, has gained popularity within circles of fitness and health practitioners, gaining the interest of people of all backgrounds. Certain parallels observed between the human physiological …


Analyzing Pseudomonas Aeruginosa With Bacteriophage Tags Using Photoacoustic Flow Cytometry, Jennifer C. Schinke Aug 2023

Analyzing Pseudomonas Aeruginosa With Bacteriophage Tags Using Photoacoustic Flow Cytometry, Jennifer C. Schinke

Electronic Theses and Dissertations

The number of daily bacterial infections is climbing and the CDC explains that this is due to the antibiotic-resistant threat in the United States. Finding a faster way of bacterial identification is necessary as it currently takes 1-4 days for a medical lab to culture and identify bacteria. Photoacoustic flow cytometry (PAFC) can be used as an alternative method resulting in swift identification within an hour (Edgar, 2019). Pseudomonas aeruginosa, cell line PA01, will be coated in up to a few hundred red dyed phages making it detectible by the photoacoustic flow cytometry system. Bacteriophages (phages) are viruses that …


Survey Of How Irregularities In The Electrical System Of The Human Heart Link To Different Heart Arrhythmias, Jazmine Boloor Aug 2023

Survey Of How Irregularities In The Electrical System Of The Human Heart Link To Different Heart Arrhythmias, Jazmine Boloor

UNLV Theses, Dissertations, Professional Papers, and Capstones

This thesis explores the circuital pathway that a signal takes within the heart throughout a full heartbeat and provides a timing analysis. It then surveys the different pathways that could arise in the electrical system of the heart, and the associated heart diseases linked to the location of each pathway. Common heart arrhythmias such as atrioventricular nodal reentrant tachycardia, atrioventricular reentrant tachycardia, atrial flutter, and atrial fibrillation are surveyed, and their pathways are analyzed. Electrocardiograms are presented to aid in understanding of the timing analysis associated with irregularity in heart function. Finally, this thesis explores an avenue of the heartbeat …


Development And Validation Of Mechatronic Systems For Image-Guided Needle Interventions And Point-Of-Care Breast Cancer Screening With Ultrasound (2d And 3d) And Positron Emission Mammography, Claire Ks Park May 2023

Development And Validation Of Mechatronic Systems For Image-Guided Needle Interventions And Point-Of-Care Breast Cancer Screening With Ultrasound (2d And 3d) And Positron Emission Mammography, Claire Ks Park

Electronic Thesis and Dissertation Repository

The successful intervention of breast cancer relies on effective early detection and definitive diagnosis. While conventional screening mammography has substantially reduced breast cancer-related mortalities, substantial challenges persist in women with dense breasts. Additionally, complex interrelated risk factors and healthcare disparities contribute to breast cancer-related inequities, which restrict accessibility, impose cost constraints, and reduce inclusivity to high-quality healthcare. These limitations predominantly stem from the inadequate sensitivity and clinical utility of currently available approaches in increased-risk populations, including those with dense breasts, underserved and vulnerable populations.

This PhD dissertation aims to describe the development and validation of alternative, cost-effective, robust, and high-resolution …


Detecting Pathobiomes Using Machine Learning, Valerie Jackson, Valerie Jackson May 2023

Detecting Pathobiomes Using Machine Learning, Valerie Jackson, Valerie Jackson

Industrial Engineering Undergraduate Honors Theses

Machine learning is a field with high growth potential due to the overall continuous progressions, developments, advancements, and improvements caused by the way it is used to help interpret and use large amounts of data [1]. One type of data that can be collected and analyzed by these machine learning models is data that is associated with DNA and information that the DNA gives. The research will be focusing specifically on using machine learning technology to detect pathobiomes indicative of salmonella pork. The pathobiome associated with salmonella is very similar to others, and this causes a problem for classification/detection with …


A Machine Learning Approach For Predicting Clinical Trial Patient Enrollment In Drug Development Portfolio Demand Planning, Ahmed Shoieb May 2023

A Machine Learning Approach For Predicting Clinical Trial Patient Enrollment In Drug Development Portfolio Demand Planning, Ahmed Shoieb

Masters Theses

One of the biggest challenges the clinical research industry currently faces is the accurate forecasting of patient enrollment (namely if and when a clinical trial will achieve full enrollment), as the stochastic behavior of enrollment can significantly contribute to delays in the development of new drugs, increases in duration and costs of clinical trials, and the over- or under- estimation of clinical supply. This study proposes a Machine Learning model using a Fully Convolutional Network (FCN) that is trained on a dataset of 100,000 patient enrollment data points including patient age, patient gender, patient disease, investigational product, study phase, blinded …


Development Of A Computational Model To Investigate Pathways And The Effects Of Treatment In Fanconi Anemia, Sabrina Kellett May 2023

Development Of A Computational Model To Investigate Pathways And The Effects Of Treatment In Fanconi Anemia, Sabrina Kellett

Biological Sciences Undergraduate Honors Theses

Fanconi Anemia (FA) is a rare type of anemia that is not easily studied and can have very detrimental effects. This disease compromises the bone marrow, resulting in decreased hemopoiesis. Symptoms of FA also include abnormalities in the brain and spinal cord, incorrect formation of the kidneys, abnormal formation of the heart and lungs, and a dramatically increased risk of developing cancer. FA can be caused by various mutations in any of the 22 genes that encode for proteins involved in what is called the FA DNA repair pathway. In healthy individuals, this pathway specifically repairs interstrand cross-links (ICLs) recognized …


Improving The Reliability And Accessibility Of Ct Perfusion Imaging In Acute Ischemic Stroke, Kevin J. Chung Feb 2023

Improving The Reliability And Accessibility Of Ct Perfusion Imaging In Acute Ischemic Stroke, Kevin J. Chung

Electronic Thesis and Dissertation Repository

CT perfusion (CTP) imaging is a validated treatment decision support tool in acute ischemic stroke. Automated analysis of CTP cerebral blood flow (CBF) and Tmax maps produces estimates of ischemic core and penumbra volumes used to determine target mismatch profiles for treatment. However, availability and utilization of CTP is low due to diagnostic variability between CTP software and technical, logistical, and radiation dose considerations that may limit its routine adoption. The objective of this doctoral research was to improve the reliability and accessibility of CTP by (1) improving diagnostic agreement between CTP software, (2) enabling perfusion imaging with standard acute …


Advancing Medical Technology For Motor Impairment Rehabilitation: Tools, Protocols, And Devices, Matthew Yough Jan 2023

Advancing Medical Technology For Motor Impairment Rehabilitation: Tools, Protocols, And Devices, Matthew Yough

Graduate Theses, Dissertations, and Problem Reports

Excellent motor control skills are necessary to live a high-quality life. Activities such as walking, getting dressed, and feeding yourself may seem mundane, but injuries to the neuromuscular system can render these tasks difficult or even impossible to accomplish without assistance. Statistics indicate that well over 100 million people are affected by diseases or injuries, such as stroke, Parkinson’s Disease, Multiple Sclerosis, Cerebral Palsy, peripheral nerve injury, spinal cord injury, and amputation, that negatively impact their motor abilities. This wide array of injuries presents a challenge to the medical field as optimal treatment paradigms are often difficult to implement due …


Longitudinal Oxygen Imaging In 3d (Bio)Printed Models, Ryan Curtis O'Connell Jan 2023

Longitudinal Oxygen Imaging In 3d (Bio)Printed Models, Ryan Curtis O'Connell

Graduate Theses, Dissertations, and Problem Reports

Electron paramagnetic resonance (EPR), and its molecular imaging modality, is a powerful tool to noninvasively map various biological and chemical markers within objects of interest. Reliable data acquisition is a major impeding factor for longitudinal hands-off measurements. Measurements are especially challenging in biomedical applications, as live objects are not static. Frequent changes occur that require constant fine recalibration of the EPR detection system, called the resonator. To enable longitudinal imaging, a technology permitting automatic digital control of resonator coupling, tuning, and EPR data acquisition was developed. Automation was achieved through the utilization of a microcontroller and digital peripheral components such …


Development Of A Low-Dose Radiation Therapy Device For Acute Respritory Distress Syndrome, Thomas Heath Davis Dec 2022

Development Of A Low-Dose Radiation Therapy Device For Acute Respritory Distress Syndrome, Thomas Heath Davis

Masters Theses

This research focuses on the development of a low dose radiotherapy (LD-RT) device for treatment of acute respiratory distress syndrome (ARDS), a respiratory illness that affects millions of people a year. The use of orthovoltage (200 – 500 keV) X-ray energy provides many advantages over traditional radiotherapy delivery with linear accelerators, such as low cost and greater accessibility. In addition, X-ray tubes have been shown throughout history to provide good treatment outcomes for pneumonia, and research has shown LD-RT to be just as effective with ARDS. This proposal summarizes my efforts in determining the dosimetric properties of a LD-RT system …


Identifying And Minimizing Underspecification In Breast Cancer Subtyping, Jonathan Cheuk-Kiu Tang Dec 2022

Identifying And Minimizing Underspecification In Breast Cancer Subtyping, Jonathan Cheuk-Kiu Tang

Master's Theses

In the realm of biomedical technology, both accuracy and consistency are crucial to the development and deployment of these tools. While accuracy is easy to measure, consistency metrics are not so simple to measure, especially in the scope of biomedicine where prediction consistency can be difficult to achieve. Typically, biomedical datasets contain a significantly larger amount of features compared to the amount of samples, which goes against ordinary data mining practices. As a result, predictive models may fail to find valid pathways for prediction during training on such datasets. This concept is known as underspecification.

Underspecification has been more accepted …


Frontiers In The Self-Assembly Of Charged Macromolecules, Khatcher O. Margossian Oct 2022

Frontiers In The Self-Assembly Of Charged Macromolecules, Khatcher O. Margossian

Doctoral Dissertations

The self-assembly of charged macromolecules forms the basis of all life on earth. From the synthesis and replication of nucleic acids, to the association of DNA to chromatin, to the targeting of RNA to various cellular compartments, to the astonishingly consistent folding of proteins, all life depends on the physics of the organization and dynamics of charged polymers. In this dissertation, I address several of the newest challenges in the assembly of these types of materials. First, I describe the exciting new physics of the complexation between polyzwitterions and polyelectrolytes. These materials open new questions and possibilities within the context …


A Two-Layer Continuous-Capillary Oxygen Transport Model: Development And Application To Blood Flow Regulation In Resting Skeletal Muscle., Keith C. Afas Aug 2022

A Two-Layer Continuous-Capillary Oxygen Transport Model: Development And Application To Blood Flow Regulation In Resting Skeletal Muscle., Keith C. Afas

Electronic Thesis and Dissertation Repository

In skeletal muscle (SM), the microcirculation distributes blood flow to capillary networks to meet local oxygen (O2) demand. Experiments using intra-vital video microscopy (IVVM) have quantified blood flow and O2 supply in capillary networks, and using an O2 exchange chamber have measured local changes in blood flow believed due to O2-dependent regulation. However, IVVM is unable to simultaneously measure capillary O2 supply and SM O2 content, implying the need for theoretical models to understand how flow regulation and SM oxygenation interact. In this thesis, a novel blood-tissue O2 transport model using …


Multicolor Fluorescence Guided Surgery For Head And Neck Cancer, Dani Szafran-Reeder Jun 2022

Multicolor Fluorescence Guided Surgery For Head And Neck Cancer, Dani Szafran-Reeder

University Honors Theses

This project aims to take a novel, NIR nerve-specific fluorophore LGW05-75⁴ and test its compatibility with a tumor-targeting affibody molecule, ABY-029⁶ that has been labeled with IRDye800CW. The overall goal is to show that these two molecules can be co-administered to show the nerves and tumor cells in real-time to better assist surgeons in a full resection while avoiding iatrogenic nerve damage.


Additive Manufacturing Of Variable Contrast Computed Tomography Anatomical Phantoms Using A Single Feedstock In Fused Filament Fabrication, Cory J. Darling May 2022

Additive Manufacturing Of Variable Contrast Computed Tomography Anatomical Phantoms Using A Single Feedstock In Fused Filament Fabrication, Cory J. Darling

University of New Orleans Theses and Dissertations

Anatomical phantoms used in biomedical education and training benefit greatly from Fused filament fabrication’s (FFF) ability to rapidly produce complex and unique models. Current materials and methods used in FFF have limited ability to accurately produce phantoms that can mimic the radiological properties of multiple biological tissues. This research demonstrates that the CT contrast of FFF produced models can be modified by varying the concentration of bismuth oxide in acrylonitrile butadiene styrene (ABS) filaments and a tunable CT contrast that mimics the CT contrast ranging from fatty tissue to cortical bone using a single composite filament without introducing artificial image …


Nanoparticles For Biomedical Applications, Joseph Kim May 2022

Nanoparticles For Biomedical Applications, Joseph Kim

Dissertations & Theses (Open Access)

This thesis presents development and evaluation of the potential of three new nanoparticles for biomedical applications. With the rapid growth of the field of nanoscience, researchers have explored developing nanoparticles for various biomedical applications, including imaging, therapy, and drug delivery. This thesis demonstrates the development of two C­60 fullerene based nanoparticles and one boron based nanoparticle to answer key questions related to their biological potential.

In the first part of the thesis, we describe synthesis and characterization of a pure boron nanoparticle containing asolectin phospholipid-based liposome construct prepared using a water-in-oil emulsion method, as a novel alternative agent for …


Cost-Effective Non-Destructive Testing Of Biomedical Components Fabricated Using Additive Manufacturing, Santiago Fabian Cobos Mar 2022

Cost-Effective Non-Destructive Testing Of Biomedical Components Fabricated Using Additive Manufacturing, Santiago Fabian Cobos

Electronic Thesis and Dissertation Repository

Biocompatible titanium-alloys can be used to fabricate patient-specific medical components using additive manufacturing (AM). These novel components have the potential to improve clinical outcomes in various medical scenarios. However, AM introduces stability and repeatability concerns, which are potential roadblocks for its widespread use in the medical sector. Micro-CT imaging for non-destructive testing (NDT) is an effective solution for post-manufacturing quality control of these components. Unfortunately, current micro-CT NDT scanners require expensive infrastructure and hardware, which translates into prohibitively expensive routine NDT. Furthermore, the limited dynamic-range of these scanners can cause severe image artifacts that may compromise the diagnostic value of …


Therapeutic Approaches For Respiratory Distress Syndrome, Franck J. Kamga Gninzeko Jan 2022

Therapeutic Approaches For Respiratory Distress Syndrome, Franck J. Kamga Gninzeko

Theses and Dissertations

Respiratory distress syndrome (RDS) is characterized by shortness of breath and low oxygen levels. RDS affects the neonatal and adult populations. In the neonatal population, RDS can be classified as NRDS (Neonatal respiratory distress syndrome), while in adults, it is known as ARDS (acute respiratory distress syndrome). This dissertation examines a therapeutic approach to NRDS and a mechanistic approach to ARDS with in vivo and in vitro models of lung injury. NRDS is characterized by a deficiency or lack of surfactant. Surfactant is an essential compound composed of phospholipids and proteins to prevent the lungs from collapsing. There are several …


Modeling Of Patient-Specific Periaortic Mechanics And Pulmonary Artery Hemodynamics Based On Phase-Contrast Magnetic Resonance Imaging Sequences., Johane H. Bracamonte Jan 2022

Modeling Of Patient-Specific Periaortic Mechanics And Pulmonary Artery Hemodynamics Based On Phase-Contrast Magnetic Resonance Imaging Sequences., Johane H. Bracamonte

Theses and Dissertations

Inverse modeling in cardiovascular medicine is a collection of methodologies that can provide non-invasive patient-specific estimations of clinical risk factors using medical imaging as inputs. Its incorporation into clinical practice has the potential to improve diagnosis and treatment planning with low associated risks and costs.

Herein, three different phase contrast magnetic resonance imaging (MRI) modalities were implemented as input data, displacement encoding with stimulated echoes (DENSE MRI) applied, and time-resolved velocity encoding phase-contrast MRI, in 1D and 3D, applied to pulmonary artery (PA) hemodynamics.

A model to account for the effect of periaortic interactions due to static and dynamic structures …


Theta Burst Brain Stimulation In Painful Diabetic Neuropathy Patients: Investigating Neural Mechanisms, Bhushan Thakkar Jan 2022

Theta Burst Brain Stimulation In Painful Diabetic Neuropathy Patients: Investigating Neural Mechanisms, Bhushan Thakkar

Theses and Dissertations

Chronic pain (CP) is a significant contributor to disability and disease burden globally. In 2019, approximately 50.2 million adults (20.4% of the US population) experienced chronic pain, contributing to $560-635 billion in direct medical costs. In addition, the worldwide prevalence of diabetes mellitus has reached epidemic proportions and is set to increase to 629 million by 2045. Almost 50% of patients with diabetes present with diabetic neuropathy (DN), and one in five patients with diabetes presents with painful DN (pDN) which is the most common cause of neuropathic pain (NP) in the US. Symptomatic treatment is the mainstay of management …


Effects Of Il-10 On Local Cell Populations And Functional Recovery Following Vml Injury, Zain Blackwell Dec 2021

Effects Of Il-10 On Local Cell Populations And Functional Recovery Following Vml Injury, Zain Blackwell

Biomedical Engineering Undergraduate Honors Theses

Volumetric muscle loss (VML) injuries are prevalent in both military personnel suffering from battlefield related incidents, and civilians following severe motor accidents. Despite its prevalence, VML has no pro-regenerative clinical treatments in place to recover some of the functional capabilities of the damaged muscle. Free flap grafting, debridement of damaged tissue, and physical therapy are the only clinical standards available that offer little functional recovery benefits, even after years of consistent treatment. In this study, anti-inflammatory cytokine interleukin-10 in conjunction with autologous minced muscle was assessed as a possible treatment for VML injuries and its influences on cellular behavior within …


The Investigations Of Nps Modulated Immunity And Immunometabolism, Brittney Leigh Ruedlinger Dec 2021

The Investigations Of Nps Modulated Immunity And Immunometabolism, Brittney Leigh Ruedlinger

Biomedical Sciences Theses & Dissertations

Cancers remain in the top noncommunicable diseases responsible for premature mortality. The heterogeneity among cancers and within tumors makes treating them ever more challenging. Our misfortune for developing cures is mocked by cancer, with the lowest probability of success (PoS) through clinical trials and FDA approval. At the basic level, there are generally two broad gaps impeding cancer eradication: the unidentified shared mechanism(s) exploited by all cancers and the therapeutic approach to intervene. Nanosecond pulse stimulation (NPS) offers a unique approach since its broad impacts intersect those often hijacked by oncogenesis. Metabolic pathways, known for dysfunctions among cancers, share a …


Designs And Outcomes Of Transcranial Magnetic Stimulation (Tms) And Repetitive Transcranial Magnetic Stimulation (Rtms) Circuits, Daniel Senda Dec 2021

Designs And Outcomes Of Transcranial Magnetic Stimulation (Tms) And Repetitive Transcranial Magnetic Stimulation (Rtms) Circuits, Daniel Senda

UNLV Theses, Dissertations, Professional Papers, and Capstones

This thesis reports the design and outcomes of several circuits intended for transcranial magnetic stimulation (TMS) and repetitive transcranial magnetic stimulation (rTMS) research. In simple terms, TMS circuits are composed of four main blocks: high voltage power source, energy storage bank, control switch, and coil. Each one of these blocks has characteristics that influence how well the circuit will perform for TMS procedures. A successful TMS research circuit must have the ability to emit controlled electromagnetic pulses through a coil connected to it. For the first block, voltages ranging from 50 V to 2 kV were used. In the second …


Frequency Dependent Diffusion Kurtosis Measurement In The Human Brain With Oscillating Gradients, Kevin B. Borsos Aug 2021

Frequency Dependent Diffusion Kurtosis Measurement In The Human Brain With Oscillating Gradients, Kevin B. Borsos

Electronic Thesis and Dissertation Repository

Oscillating gradient spin-echo (OGSE) is an implementation of diffusion MRI that enables shorter effective diffusion times than the conventional pulse gradient spin-echo (PGSE) by periodically modulating the diffusion gradient. Measurements of the diffusion kurtosis, which reflects the degree of restricted diffusion, have previously been prohibited with OGSE due to technical limitations of clinical gradient systems. This thesis presents a novel oscillating gradient waveform that enables the measurement of kurtosis using OGSE without requiring advanced gradient hardware. Decreases of kurtosis are observed in OGSE acquisitions of healthy human subjects relative to PGSE, demonstrating the dependence of the kurtosis on oscillation frequency. …