Engineering Commons^™

Evaluation Of Functional Near Infrared Spectroscopy (Fnirs) For Assessment Of The Visual And Motor Cortices In Adults, Brenna Giacherio

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Introduction: Functional near-infrared spectroscopy (fNIRS) is a relatively young technique in the field of medical imaging. As such, it has yet to be widely implemented for clinical use, despite its promising advantages. However, unlike fMRI-its much bulkier and costly counterpart-fNIRS has yet to be proven as a standalone imaging tool within a clinical setting, particularly that of ophthalmology or physical therapy.

Methods: Ten healthy young adults (23.8 ± 4.8 years) participated in the study. Activation of the visual cortex was achieved utilizing various reversing checkerboard stimuli across three data collection sessions for each participant. Further, activation of the motor cortex …

Rab3a As A Modulator Of Homeostatic Synaptic Plasticity, Andrew G. Koesters

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The nervous system is faced with perturbations in activity levels throughout development and in disease or injury states. Neurons need to adapt to these changes in activity, but also need to maintain circuit firing within a normal range to stabilize the network from becoming too excited or too depressed. Homeostatic synaptic plasticity, the compensatory increase or decrease in synaptic strength as a result of excessive circuit inhibition or excitation, is a mechanism that the nervous system utilizes to keep network activity at normal levels. Despite intense effort, little is known about the mechanisms underlying homeostatic synaptic plasticity. Numerous studies have …

Segmentation And Analysis Of Mris Of Infants With Dysphagia, Irfaan A. Dar

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Neonates are at a rapid stage of development from birth throughout childhood. Impairments to certain cortical areas can result in long lasting neuro-cognitive dysfunctions. Disorders to the swallowing neural pathways can have detrimental effects throughout life course since methods to provide nutrition can be comprised. Dysphagia, or the inability to swallow, can be caused by a multitude of reasons, chiefly neurological, but the underlying disruptions to the neural pathways are not defined. In this study we investigated the growth of multiple cortical areas involved in the swallowing pathway and categorized feeding outcomes with neural growth. Results showed that infants that …

Finite Element Simulation Of Skull Fracture Evoked By Fall Injuries, Anthony Vicini

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This study presents novel predictive equations for von Mises stresses and deflection of bones in the frontal and lateral regions of the skull. The equations were developed based on results of a finite element model developed here. The model was validated for frontal and lateral loading conditions with input values mimetic to fall scenarios. Using neural network processing of the information derived from the model achieved R2 values of 0.9990 for both the stress and deflection. Based on the outcome of the fall victims, a threshold von Mises stress of 40.9 to 46.6 MPa was found to indicate skull fracture …

The Role Of Subunit Iii In The Functional And Structural Regulation Of Cytochrome C Oxidase In Rhodobacter Spheroids, Khadijeh Salim Alnajjar

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Cytochrome c oxidase (COX) catalyzes the oxidation of ferrocytochrome c and the reduction of oxygen to water while concomitantly translocating protons across the inner mitochondrial membrane. The catalytic core of COX consists of three subunits that are conserved from the bacterial to the mitochondrial forms of the enzyme. Subunits I and II (SUI and SUII) contain the metal centers where electrons are transferred and oxygen binds for reduction. Subunit III (SUIII) does not contain any metals and has an unknown function. It contains three conserved histidine residues (3, 7 and 10) that are surface exposed and are in close proximity …

A Method For Non-Invasive, Automated Behavior Classification In Mice, Using Piezoelectric Pressure Sensors, Steven R. Gooch

Theses and Dissertations--Electrical and Computer Engineering

While all mammals sleep, the functions and implications of sleep are not well understood, and are a strong area of investigation in the research community. Mice are utilized in many sleep studies, with electroencephalography (EEG) signals widely used for data acquisition and analysis. However, since EEG electrodes must be surgically implanted in the mice, the method is high cost and time intensive. This work presents an extension of a previously researched high throughput, low cost, non-invasive method for mouse behavior detection and classification. A novel hierarchical classifier is presented that classifies behavior states including NREM and REM sleep, as well …

Peroxisome Proliferator-Activated Receptor Alpha: Insight Into The Structure, Function And Energy Homeostasis, Dhawal P. Oswal

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Peroxisome proliferator-activated receptor alpha (PPAR alpha) belongs to the family of ligand-activated nuclear transcription factors and serves as a lipid sensor to regulate nutrient metabolism and energy homeostasis. The transcriptional activity of PPAR alpha is thought to be regulated by the binding of exogenous ligands (example, fenofibrate, TriCor), as well as endogenous ligands including fatty acids and their derivatives. Although long-chain fatty acids (LCFA) and their thioesters (long-chain fatty acyl-CoA; LCFA-CoA) have been shown to activate PPAR alpha of several species, the true identity of high-affinity endogenous ligands for human PPAR alpha (hPPAR alpha) has been more elusive. This two …

Physiological And Transcriptional Memory In Guard Cells During Repetitive Dehydration Stress, Laetitia Virlouvet, Michael E. Fromm

Nebraska Center for Biotechnology: Faculty and Staff Publications

Arabidopsis plants subjected to a daily dehydration stress and watered recovery cycle display physiological and transcriptional stress memory. Previously stressed plants have stomatal apertures that remain partially closed during a watered recovery period, facilitating reduced transpiration during a subsequent dehydration stress. Guard cells (GCs) display transcriptional memory that is similar to that in leaf tissues for some genes, but display GC-specific transcriptional memory for other genes. The rate-limiting abscisic acid (ABA) biosynthetic genes NINE-CIS-EPOXYCAROTENOID DIOXYGENASE 3 (NCED3) and ALDEHYDE OXIDASE 3 (AAO3) are expressed at much higher levels in GCs, particularly during the watered recovery interval, relative to their low …

The Pseudomonas Syringae Type Iii Effector Hopd1 Suppresses Effector-Triggered Immunity, Localizes To The Endoplasmic Reticulum, And Targets The Arabidopsis Transcription Factor Ntl9, Anna Block, Tania Y. Toruno, Christian G. Elowsky, Chi Zhang, Jens Steinbrenner, Jim Beynon, James R. Alfano

Nebraska Center for Biotechnology: Faculty and Staff Publications

Pseudomonas syringae type III effectors are known to suppress plant immunity to promote bacterial virulence. However, the activities and targets of these effectors are not well understood. We used genetic, molecular, and cell biology methods to characterize the activities, localization, and target of the HopD1 type III effector in Arabidopsis. HopD1 contributes to P. syringae virulence in Arabidopsis and reduces effector-triggered immunity (ETI) responses but not pathogen-associated molecular pattern-triggered immunity (PTI) responses. Plants expressing HopD1 supported increased growth of ETI-inducing P. syringae strains compared with wild-type Arabidopsis. We show that HopD1 interacts with the membrane-tethered Arabidopsis transcription factor NTL9 and …

A Comprehensive View Of Electrosleep: The History, Finite Element Models And Future Directions, Berkan Guleyupoglu

Dissertations and Theses

Transcranial Electrical Stimulation (tES) encompasses all methods of non-invasive current application to the brain used in research and clinical practice. We present the first comprehensive and technical review, explaining the evolution of tES in both terminology and dosage over the past 100 years of research to present day. Current transcranial Pulsed Current Stimulation (tPCS) approaches such as Cranial Electrotherapy Stimulation (CES) descended from Electrosleep (ES) through Cranial Electro-stimulation Therapy (CET), Transcerebral Electrotherapy (TCET), and NeuroElectric Therapy (NET) while others like Transcutaneous Cranial Electrical Stimulation (TCES) descended from Electroanesthesia (EA) through Limoge, and Interferential Stimulation. Prior …

Pre-Saccadic Modulation Of The Visually Evoked Potential, Leslie Guadron

Dissertations and Theses

Saccades are rapid eye movements that allow us to focus the fovea on different parts of our visual environment. Many psychophysical studies have shown that subjects can discriminate stimuli presented at the saccadic target better than at any other location before an eye movement is made. It is believed that covert attention allotted to the intended destination of a saccade, called pre-saccadic attention, accounts for the improved discrimination of stimuli. Covert top-down attention, which consists of orienting your attention, and not your gaze, to an object in your visual periphery, is known to facilitate behavioral performance in a manner similar …

Coupling Graphs, Efficient Algorithms And B-Cell Epitope Prediction, Liang Zhao, Steven C. H. Hoi, Zhenhua Li, Limsoon Wong, Hung Nguyen

Research Collection School Of Computing and Information Systems

Coupling graphs are newly introduced in this paper to meet many application needs particularly in the field of bioinformatics. A coupling graph is a two-layer graph complex, in which each node from one layer of the graph complex has at least one connection with the nodes in the other layer, and vice versa. The coupling graph model is sufficiently powerful to capture strong and inherent associations between subgraph pairs in complicated applications. The focus of this paper is on mining algorithms of frequent coupling subgraphs and bioinformatics application. Although existing frequent subgraph mining algorithms are competent to identify frequent subgraphs …

Chemosensitive Neurons Of The Locus Coeruleus And The Nucleus Tractus Solitarius: Three Dimensional Morphology And Association With The Vasculature, Cathy D. Graham

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We studied the 3 dimensional structure of LC and cNTS neurons from neonatal rats. Neurons were identified as either chemosensitive or nonchemosensitive based on their firing rate response to hypercapnia, using whole-cell patch clamping and were passively loaded with Lucifer Yellow. The identified, loaded neurons were reconstructed and analyzed using Neurolucida Neuron Tracing Software. Chemosensitive LC neurons have less rounded soma than nonchemosensitive neurons, and they have dendrites arising from two poles to produce a fusiform appearance. The dendritic branches extend a greater distance from the soma of chemosensitive than nonchemosensitive neurons. Conversely, chemosensitive cNTS neurons were found to have …

Guanine Nucleotide Exchange Activity Of Phospholipase D2 And Its Regulation, Madhupriya Mahankali

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Phospholipase D2 (PLD2) is a cell membrane lipase that catalyzes the break down of phosphatidyl choline (PC) to phosphatidic acid (PA) and choline. PA is one of the major lipid second messengers that modulate a wide variety of signaling pathways, which are crucial for various cellular functions. In addition to this, PLD2 via binding to a large number of proteins and thereby regulates them independent of its lipase activity. Whereas PLD2 is involved in plethora of cellular functions, high levels of protein and/or activity of PLD2 are reported in variety of disease conditions, such as cancer metastasis and chronic inflammation …

Integration Of Instrumentation And Processing Software Of A Laser Speckle Contrast Imaging System, Jacob James Carrick

Dissertations, Master's Theses and Master's Reports - Open

Laser speckle contrast imaging (LSCI) has the potential to be a powerful tool in medicine, but more research in the field is required so it can be used properly. To help in the progression of Michigan Tech's research in the field, a graphical user interface (GUI) was designed in Matlab to control the instrumentation of the experiments as well as process the raw speckle images into contrast images while they are being acquired. The design of the system was successful and is currently being used by Michigan Tech's Biomedical Engineering department. This thesis describes the development of the LSCI GUI …

Biom 3110: Medical Physiology (Syllabus), Bradford D. Pendley

Biomedical Engineering Syllabi Archive

Course Description: Basic principles of human physiology and how these are applied in medicine and biomedical engineering problem and devices; physiological principles using appropriate mathematical and engineering models to construct an understanding of how the body works as an integrated system.

Friction Coefficients For Dried Distillers Grains On Eight Structural Surfaces, G. C. Nyendu, S. Pflum, P. Schumacher, C. J. Bern, T. J. Brumm

Biological Engineering Faculty Publications

Static and dynamic coefficients of friction on structural surfaces play important roles in the power requirements and material selection for equipment used in handling and storing agricultural commodities. However, friction data on dried distillers grains with solubles (DDGS) is limited. Further, lack of a standardized method for determining friction coefficient on grain handling materials presents a challenge. This article describes studies carried out to determine the static coefficient of friction (•_s) and dynamic coefficient of friction (•_d) for corn DDGS at 10%, 8.2%, and 6.5% moisture content (all moistures are % wet basis) on eight structural surfaces: High-Density Polyethylene (HDPE), …

The Effect Of Simultaneous, Irrelevant Auditory And Visual Stimuli On A Forced-Attention Dichotic Listening Test, Keri Davis

Theses and Dissertations

Many of the studies examining cognitive control during selective attention across different sensory modalities conflict. This study was designed to study the effect of an irrelevant visual stimulus and an auditory distraction of backward speech on a forced attention dichotic listening test. I predicted that the visual stimulus and backward speech would not have a significant effect on the ear advantage. The results showed that all subjects were able to force their attention to the ear regardless of the visual or auditory distracters. In addition, I found that an irrelevant visual stimulus affects auditory attention more so in the left …

Development Of A Compact, Low-Cost Wireless Device For Biopotential Acquisition, Graham Kelly

Theses and Dissertations

A low-cost circuit board design is presented, which in one embodiment is smaller than a credit card, for biopotential (EMG, ECG, or EEG) data acquisition, with a focus on EEG for brain-computer interface applications. The device combines signal conditioning, low-noise and high-resolution analog-to-digital conversion of biopotentials, user motion detection via accelerometer and gyroscope, user-programmable digital pre-processing, and data transmission via Bluetooth communications. The full development of the device to date is presented, spanning three embodiments. The device is presented both as a functional data acquisition system and as a template for further development based on its publicly-available schematics and computer-aided …

Novel 3d Head And Neck Cancer Model To Evaluate Chemotherapeutic Efficacy, Kelly Morgan

Theses and Dissertations

HNSCC accounts for 7 percent of all new cancer occurrences. Despite currently available treatments, there continues to be a high mortality and recurrence rate in HNSCC. Well over 50 percent of all cancer patients receive chemotherapy as a standard treatment. However, only 5 percent of these cases have been shown to help with treatment of the disease. Formerly, two options were available for drug testing: in vivo animal models, and in vitro two-dimensional models. While in vivo models remain the most representative, their use is burdened by high costs, time constraints, and ethical concerns. 2D models are simple to use …

Magnesium-Titanium Alloys For Biomedical Applications, Ilona Hoffmann

Theses and Dissertations--Chemical and Materials Engineering

Magnesium has been identified as a promising biodegradable implant material because it does not cause systemic toxicity and can reduce stress shielding. However, it corrodes too quickly in the body. Titanium, which is already used ubiquitously for implants, was chosen as the alloying element because of its proven biocompatibility and corrosion resistance in physiological environments. Thus, alloying magnesium with titanium is expected to improve the corrosion resistance of magnesium.

Mg-Ti alloys with a titanium content ranging from 5 to 35 at.-% were successfully synthesized by mechanical alloying. Spark plasma sintering was identified as a processing route to consolidate the alloy …

A Nonrigid Registration Method For Correcting Brain Deformation Induced By Tumor Resection, Yixun Liu, Chengjun Yao, Fotis Drakopoulos, Jinsong Wu, Liangfu Zhou, Nikos Chrisochoides

Computer Science Faculty Publications

Purpose: This paper presents a nonrigid registration method to align preoperative MRI with intraoperative MRI to compensate for brain deformation during tumor resection. This method extends traditional point-based nonrigid registration in two aspects: (1) allow the input data to be incomplete and (2) simulate the underlying deformation with a heterogeneous biomechanical model.

Methods: The method formulates the registration as a three-variable (point correspondence, deformation field, and resection region) functional minimization problem, in which point correspondence is represented by a fuzzy assign matrix; Deformation field is represented by a piecewise linear function regularized by the strain energy of a heterogeneous biomechanical …

Continuous Monitoring Of Turning In Patients With Movement Disability, Mahmoud Ahmed El-Gohary, Sean Pearson, James Mcnames, Martina Mancini, Fay Horak, Sabato Mellone, Lorenzo Chiari

Electrical and Computer Engineering Faculty Publications and Presentations

Difficulty with turning is a major contributor to mobility disability and falls in people with movement disorders, such as Parkinson’s disease (PD). Turning often results in freezing and/or falling in patients with PD. However, asking a patient to execute a turn in the clinic often does not reveal their impairments. Continuous monitoring of turning with wearable sensors during spontaneous daily activities may help clinicians and patients determine who is at risk of falls and could benefit from preventative interventions. In this study, we show that continuous monitoring of natural turning with wearable sensors during daily activities inside and outside the …

Identifying Performance Criteria Of Fully Bioresorbable Scaffolds For Endovascular Applications, Jahid Ferdous

Theses and Dissertations

Background: Bioresorbable scaffolds (BRS) have revolutionized percutaneous coronary intervention in clinical cardiovascular medicine. As opposed to permanent alternatives such as metallic stents, BRS have an inherent potential to reduce the occurrence of untoward events such as vessel re-narrowing or thrombosis by virtue of undergoing complete and controlled resorption post- implantation. While BRS platforms demonstrate a clear potential to mitigate risk stemming from incomplete vessel healing, they introduce a new set of considerations to clinical safety and efficacy. Foremost among these issues is the fate of and biological response to material by-products that evolve throughout the scaffold degradation and erosion processes, …

Isolation Of Natural Nrf2 Activators From American Ginseng, Akrm Abdalrahman

Theses and Dissertations

Nuclear factor erythroid-2 related factor 2 (Nrf2), a major transcription factor of the endogenous antioxidant defense system, has been proposed as a potential therapeutic target for the treatment of various diseases. However, a small molecule-driven Nrf2 signaling therapeutic approach remains to be established. Herein, we report one such possibility discovered by the bioassay-based fractionation of American ginseng. Since crude extract of American ginseng was found to suppress the expression of inducible nitric oxide synthase (iNOS) in lipopolysaccharide (LPS)-inflamed macrophages via activating Nrf2, we further fractioned the crude extract using solvents including hexane, dichloromethane, ethyl acetate, butanol, and water, and found …

Novel Conditioning Protocols Focusing On Oxygen Manipulation To Enhance Stem Cell Transplantation, Brandon William Hanna

Theses and Dissertations

Musculoskeletal tissue engineering involves the creation of multiple tissue types that interact together to form a particular function related to motion and maintaining the body's frame. In order to create a fully functional musculoskeletal system, a concrete method for the creation of the different tissue types must first be completed. Of the different tissue components related to the function of a musculoskeletal system, these studies deal with preconditioning circumstances of stem cells that will differentiate into cartilage and bone. These studies also deal with methods for the creation of functional bone and cartilage to be combined for the creation of …

Android-Based Smartphone Application Simulation And Systematic Design To Reduce Medication Administration Error In Prehospital Emergency Care., Natalie Vazquez

Theses and Dissertations

Since 1999 when the report To Err is Human: Building a Safer Health System was released, medical errors have come into focus (Kohn, 2000). In an effort to reduce medication administration errors in prehospital emergency care, an android-based smartphone application simulation was created. The app has components including QR barcode scanning, text to speech for medication cross-checking, weight-based medication dose calculations, and time stamped medication data wirelessly transferring to a database in real-time. Color standard identification was implemented, aiding to a designed systematic process for patient treatment to reduce medication errors. Direct observation was performed of emergency patient calls with …

Design And Validation Of A Computational Model For Study Of Scapholunate Joint Kinematics, Edward J. Tremols

Theses and Dissertations

As computational power has increased, computational modeling has become a very promising tool to model the biomechanics of complex joint systems. Musculoskeletal computational models have become more complex when compared to original iterations which utilized a number of simplifications. This thesis utilized a three-dimensional computational model of the wrist joint structure to investigate scapholunate kinematics. The model accurately represented the bony anatomy of the wrist and hand and represented soft tissue structures such as ligaments, tendons, and other surrounding tissues. Creation of the model was done using commercially available computer-aided design and medical image processing software, and utilized the rigid …

Theoretical And Experimental Investigations To Improve The Performance Of Surface Acoustic Wave (Saw) Biosensors, Mandek Richardson

USF Tampa Graduate Theses and Dissertations

The objective of this dissertation is to improve the performance of surface acoustic wave (SAW) biosensors for use in point-of-care-testing (POCT) applications. SAW biosensors have the ability to perform fast, accurate detection of an analyte in real time without the use of labels. However, the technology suffers from the inability to differentiate between specific and non-specific binding. Due to this limitation, direct testing of bodily fluids using SAW sensors to accurately determine an analyte's concentration is difficult. In addition, these sensors are challenged by the need to detect small concentrations of a biomarker that are typically required to give a …

3d Conductive Nanocomposite Scaffold For Bone Tissue Engineering, Aref Shahini, Mostafa Yazdimamaghani, Kenneth J. Walker, Margaret A. Eastman, Hamed Hatami-Marbini, Brenda J. Smith, John L. Ricci, Sundar V. Madihally, Daryoosh Vashaee, Lobat Tayebi

Chemical and Biochemical Engineering Faculty Research & Creative Works

Bone healing can be significantly expedited by applying electrical stimuli in the injured region. Therefore, a three-dimensional (3D) ceramic conductive tissue engineering scaffold for large bone defects that can locally deliver the electrical stimuli is highly desired. In the present study, 3D conductive scaffolds were prepared by employing a biocompatible conductive polymer, ie, poly(3,4-ethylenedioxythiophene) poly (4-styrene sulfonate) (PEDOT:PSS), in the optimized nanocomposite of gelatin and bioactive glass. For in vitro analysis, adult human mesenchymal stem cells were seeded in the scaffolds. Material characterizations using hydrogen-1 nuclear magnetic resonance, in vitro degradation, as well as thermal and mechanical analysis showed that …