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Full-Text Articles in Bioelectrical and Neuroengineering

A Functional Ultrasound Imaging (Fusi) Pipeline For Investigating Brain-Wide Hemodynamics During Torpor-Like Hypothermia, Owen J. Culver Aug 2026

A Functional Ultrasound Imaging (Fusi) Pipeline For Investigating Brain-Wide Hemodynamics During Torpor-Like Hypothermia, Owen J. Culver

McKelvey School of Engineering Graduate Student Theses & Dissertations

Torpor is a regulated state of reduced metabolic demand that enables animals to conserve energy under unfavorable environmental conditions. The controlled induction of a similar state, termed synthetic torpor, has potential applications in ischemic protection, organ preservation, cancer treatment, radiation protection, and long-term spaceflight. Although neuronal populations within the preoptic hypothalamus have been shown to initiate hypothermic and hypometabolic states, the distributed cerebral hemodynamic dynamics accompanying their induction and maintenance remain poorly understood. In this thesis, we developed an accessible functional ultrasound imaging (fUSI) acquisition and analysis pipeline and applied it to investigate cerebral hemodynamics during chemogenetic activation of the …


Voltage-Sensor–Targeting Modulators Of Iks: Identifying Critical Functional Groups Of C28 Via Electrophysiology And Sar Modeling, Jiacheng Huang May 2026

Voltage-Sensor–Targeting Modulators Of Iks: Identifying Critical Functional Groups Of C28 Via Electrophysiology And Sar Modeling, Jiacheng Huang

McKelvey School of Engineering Graduate Student Theses & Dissertations

IKs (KCNQ1/KCNE1) channels are essential for cardiac repolarization, and their dysfunction contributes to arrhythmogenic disorders such as Long QT Syndrome type 1 (LQT1). Pharmacological activation of IKs has therefore emerged as a promising therapeutic strategy. C28, a recently identified voltage-sensor–targeting activator, has been shown to markedly shift KCNQ1/KCNE1 voltage dependence and enhance current amplitude, validating the voltage-sensing domain (VSD) as a druggable site. However, the structural determinants that underlie C28’s activity remain incompletely understood. In this study, we aimed to identify critical functional groups of C28 by screening a structurally diverse set of C28-like analogs and evaluating their …


Data-Driven Insights Into Spatial Patterns And Disease Etiologies Of White Matter Hyperintensities, Sugandha Roy May 2024

Data-Driven Insights Into Spatial Patterns And Disease Etiologies Of White Matter Hyperintensities, Sugandha Roy

McKelvey School of Engineering Graduate Student Theses & Dissertations

In this thesis, we have applied Orthogonal Projective Non-Negative Matrix Factorization (opNMF) to identify spatial patterns of white matter hyperintensities (WMH) within UK Biobank's imaging data. Our selection criteria excluded subjects with a history of neurological, mental, and specific cerebrovascular conditions, allowing us to focus on WMH patterns in a healthy aging population. We have interrogated the association of location-specific WMHs with a variety of demographic, clinical, and genetic factors. Our multivariable regression analysis evaluates the strength and nature of the associations between these factors and WMH distribution. The analysis integrates variables such as age, sex, smoking habits, medication usage …


The Effect Of Spinal Cord Stimulation And Video Games Training On Body-Machine Interface Control, Jie Fei May 2023

The Effect Of Spinal Cord Stimulation And Video Games Training On Body-Machine Interface Control, Jie Fei

McKelvey School of Engineering Graduate Student Theses & Dissertations

Damage to the spinal cord causes long-lasting loss of motor and sensory function, and currently, there is no ‘cure’ for paralysis. However, even people with severe spinal cord injuries (SCI) have some residual mobility. Studies have shown that transcutaneous electrical spinal cord stimulation (tSCS) combined with functional training targeting residual mobility can further improve the motor function of individuals with SCI. In this study, we present a technical framework that aims to enhance rehabilitation outcomes by targeting residual mobility through a motor training-based approach. Our technical framework centers around a non-invasive body-machine interface (BoMI) that relies on the use of …


Preparing Non-Human Primates To Study Hand-Eye Coordination In Frontal Eye Fields (Fef) During Delayed Movement Task, Juliusz Cydzik May 2023

Preparing Non-Human Primates To Study Hand-Eye Coordination In Frontal Eye Fields (Fef) During Delayed Movement Task, Juliusz Cydzik

McKelvey School of Engineering Graduate Student Theses & Dissertations

ABSTRACT OF THE THESIS Preparing Non-Human Primates to Study Hand-Eye Coordination in Frontal Eye Fields (FEF) During Delayed Movement Task by Juliusz Cydzik Master of Science in Biomedical Engineering Washington University in St. Louis, 2023 Professor Lawrence Snyder, Chair Hand-eye coordination enables humans and non-human primates to use their hands and eyes to perform various tasks. We are interested in coordination at the systems level, where saccades and reaches are encoded. The parietal reach region (PRR), situated at the posterior end of the intraparietal sulcus (IPS) and overlapping portions of the medial intraparietal area (MIP) and V6a, is commonly attributed …


The Influence Of Electrical Stimulation Pulse Frequency Of Macro-Sieve Electrode On Rat Sciatic Nerve Detection Threshold, Jingyuan Zhang Dec 2022

The Influence Of Electrical Stimulation Pulse Frequency Of Macro-Sieve Electrode On Rat Sciatic Nerve Detection Threshold, Jingyuan Zhang

McKelvey School of Engineering Graduate Student Theses & Dissertations

No abstract provided.


Application Of Neural Networks To Predict Patient-Specific Cellular Parameters In Computational Cardiac Models, Chang Hi Lee May 2022

Application Of Neural Networks To Predict Patient-Specific Cellular Parameters In Computational Cardiac Models, Chang Hi Lee

McKelvey School of Engineering Graduate Student Theses & Dissertations

Sudden cardiac death(SCD) is a significant cause of death that accounts for more than 180,000 deaths in the US and 4 million deaths worldwide annually. SCDs are mainly caused by irregular heartbeats called arrhythmias, which are caused by abnormal electrical activity within the heart. Precision medicine, in the form of personalized computational cardiac models of a patient’s heart, can suggest optimal therapies for cardiac arrhythmias. Prior work has used finite element meshes derived from cardiac MRIs to simulate cardiac electrical activity. In this study, I sought to augment this approach by developing a neural network to learn the parameters that …


Chronic Nerve Interfacing Utilizing Graft-Embedded Regenerative Macro-Sieve Electrodes, Amrita Nishtala May 2018

Chronic Nerve Interfacing Utilizing Graft-Embedded Regenerative Macro-Sieve Electrodes, Amrita Nishtala

McKelvey School of Engineering Graduate Student Theses & Dissertations

Custom-designed macro-sieve electrodes represent a novel means of facilitating chronic high specificity nerve stimulation needed to control distal nerve musculature and restore sensorimotor function. Implantation of these electrodes requires the transection of the nerve, which has shown to disrupt muscle fiber distribution. This present study assesses the feasibility of implementing these electrodes in an end-to-side nerve graft. The macro-sieve electrodes were fabricated and micro-surgically implanted into 3.2 cm nerve autografts harvested from the sciatic nerve of 12 male Lewis rats. Electrode-enabled nerve grafts were micro-surgically implanted in an end-to-side manner into donor rat sciatic nerves without the need for a …


Characterization Of The High Frequency Alternating Current Block In The Rat Sciatic Nerve Using Cuff Electrodes And Macro-Sieve Electrodes, Soumyajit Ray Aug 2017

Characterization Of The High Frequency Alternating Current Block In The Rat Sciatic Nerve Using Cuff Electrodes And Macro-Sieve Electrodes, Soumyajit Ray

McKelvey School of Engineering Graduate Student Theses & Dissertations

Tripolar cuff electrodes were designed, fabricated and non-chronically implanted in the sciatic nerve of two-month-old Lewis rats. A proximal constant current stimulus to the nerve was blocked by applying a high frequency sinusoidal signal to the distally placed tripolar cuff electrode. The frequency voltage characteristic of the blocking signal was obtained. Complete block was not achieved using variants of the tripolar cuff design and bipolar cuff electrodes. Single and dual macro-sieve electrode assemblies were designed, fabricated and chronically implanted in the sciatic nerve of Lewis rats. After a four-month period for regeneration four different electrode configurations were tested to enable …


Spontaneous Firing Of Sensory Neurons Modulates The Gain In The Downstream Circuit Of A Simple Olfactory System, Matthew O'Neill Aug 2015

Spontaneous Firing Of Sensory Neurons Modulates The Gain In The Downstream Circuit Of A Simple Olfactory System, Matthew O'Neill

McKelvey School of Engineering Graduate Student Theses & Dissertations

In locusts and other insects, odorants are transduced into electrical signal by the olfactory receptor neurons and transmitted to central circuits for further processing. Previous studies have shown that exogenous variables (e.g., flow rates, humidity, temperature, odor mixtures, etc.) can influence the responses of the sensory neurons and therefore modulate the central circuits. However, how the sensory neuron activity is manipulated to achieve adaptive gain control in the following circuit is yet to be understood. It is possible that the magnitude of the stimulus-evoked response in the receptor neurons, their spontaneous activity, or both of these factors can change how …