Biomedical Engineering and Bioengineering Commons^™

Utilizing Functional Near-Infrared Spectroscopy For Prediction Of Cognitive Workload In Noisy Work Environments, Ryan Gabbard, Mary E. Fendley, Irfaan A. Dar, Rik Warren, Nasser H. Kashou

Biomedical, Industrial & Human Factors Engineering Faculty Publications

Occupational noise frequently occurs in the work environment in military intelligence, surveillance, and reconnaissance operations. This impacts cognitive performance by acting as a stressor, potentially interfering with the analysts’ decision-making process. We investigated the effects of different noise stimuli on analysts’ performance and workload in anomaly detection by simulating a noisy work environment. We utilized functional near-infrared spectroscopy (fNIRS) to quantify oxy-hemoglobin (HbO) and deoxy-hemoglobin concentration changes in the prefrontal cortex (PFC), as well as behavioral measures, which include eye tracking, reaction time, and accuracy rate. We hypothesized that noisy environments would have a negative effect on the participant in …

Macrodamage Accumulation Model For A Human Femur, Farah Hamandi, Tarun Goswami

Biomedical, Industrial & Human Factors Engineering Faculty Publications

The objective of this study was to more fully understand the mechanical behavior of bone tissue that is important to find an alternative material to be used as an implant and to develop an accurate model to predict the fracture of the bone. Predicting and preventing bone failure is an important area in orthopaedics. In this paper, the macrodamage accumulation models in the bone tissue have been investigated. Phenomenological models for bone damage have been discussed in detail. In addition, 3D finite element model of the femur prepared from imaging data with both cortical and trabecular structures is delineated using …

Human Biomechanics Ii Course Project, Abdelaziz Mohammad

Best Integrated Writing

Mohammad tested Human Arm Module PASCO ME-6807A, in order to determine some of the biomechanical characteristics, such as force, tension, instantaneous angular velocity, and acceleration vs. angular position required for various movements and arm positions in space.

Brain Lesions Among Orally Fed And Gastrostomy-Fed Dysphagic Preterm Infants: Can Routine Qualitative Or Volumetric Quantitative Magnetic Resonance Imaging Predict Feeding Outcomes?, Nasser H. Kashou, Irfaan Akram Dar, Mohamed A. El-Mahdy, Charles Pluto, Mark Smith, Ish K. Gulati, Warren Lo, Sudarshan R. Jadcherla

Biomedical, Industrial & Human Factors Engineering Faculty Publications

Introduction: The usefulness of qualitative or quantitative volumetric magnetic resonance imaging (MRI) in early detection of brain structural changes and prediction of adverse outcomes in neonatal illnesses warrants further investigation. Our aim was to correlate certain brain injuries and the brain volume of feeding-related cortical and subcortical regions with feeding method at discharge among preterm dysphagic infants.

Materials and methods: Using a retrospective observational study design, we examined MRI data among 43 (22 male; born at 31.5 ± 0.8 week gestation) infants who went home on oral feeding or gastrostomy feeding (G-tube). MRI scans were segmented, and volumes of brainstem, …

Probabilistic Analysis Of Wear Of Polymer Material Used In Medical Implants, V. Perel, Tarun Goswami

Biomedical, Industrial & Human Factors Engineering Faculty Publications

Probabilistic methods are applied to the study of fatigue wear of sliding surfaces. A variance of time to failure (to occurrence of maximum allowable wear depth) is evaluated as a function of a mean wear rate of normal wear and a size of wear particles. A method of estimating probability of failure-free work during a certain time interval (reliability) is presented. An effect of the bedding-in phase of wear on the reliability is taken into account. Experimental data for Ultra High Molecular Weight Polyethylene (UHMWPE) cups of artificial hip implants is used to make numerical calculations.

Context-Dependence Of Physiological Systems: Environment-Physiology Interactions In The Respiratory Control System, Joseph M. Santin

Browse all Theses and Dissertations

We know that animals are tuned to survive different environmental conditions or else life would not exist. Unfortunately, this is often forgotten or ignored when designing experiments. As Marsh Tenney articulated, "The physiologist keeps the whole always in mind. He accepts the tactical necessity of reductionism to understand parts, but, once done, for him it is only the beginning, never the end” (from Remmers, 2005). In an era when it is all too common to take environmental complexity out of the organism to understand physiology, my work puts some of that complexity back in the study of organisms. I take …

Functions Of The Apical Na+/ K+/ 2cl- Cotransporter 1 In Choroid Plexus Epithelial Cells., Jeannine Marie Crum Gregoriades

Browse all Theses and Dissertations

Choroid plexus epithelial cells (CPECs) secrete cerebrospinal fluid (CSF) and regulate its electrolyte composition. CPECs express both the Na⁺/ K⁺ ATPase and the Na⁺/ K⁺/ 2Cl^- cotransporter 1 (NKCC1) on their apical membrane (CSF facing), deviating from the typical basolateral membrane location in chloride secretory epithelia. Given this unusual location of NKCC1 and the unknown intracellular Na⁺ and Cl^- concentrations of CPECs, the cotransporter function in these cells is not understood. Further, the direction of net ion and associated water fluxes mediated by NKCC1 under basal physiological conditions in CPECs …

Persistent Inward Currents Play A Role In Muscle Dysfunction Seen In Myotonia Congenita, Ahmed Alaa Hawash

Browse all Theses and Dissertations

Myotonia congenita is a rare skeletal muscle channelopathy caused by a reduced chloride channel (ClC-1) current, which results in debilitating muscle hyperexcitability, prolonged contractions, and transient episodes of weakness. The excitatory events that trigger myotonic action potentials in the absence of stabilizing ClC-1 current are not fully understood. My in vitro intracellular recordings from a mouse homozygous knockout of ClC-1 revealed a slow after-depolarization (AfD) that triggers myotonic action potentials. The AfD is well-explained by a tetrododoxin-sensitive and voltage-dependent Na+ persistent inward current (NaPIC). Notably, this NaPIC undergoes slow inactivation over seconds, thus providing the first mechanistic explanation for the …

Novel Mechanisms Underlying Warm-Up And Percussion Myotonia In Myotonia Congenita, Kevin Richard Nnovak

Browse all Theses and Dissertations

Patients with myotonia congenita have muscle hyperexcitability due to loss-of-function mutations in the ClC-1 chloride channel in skeletal muscle, which causes spontaneous firing of muscle action potentials (myotonia), producing muscle stiffness. Triggers for myotonia can occur voluntarily at the neuromuscular junction or involuntarily by striking the muscle with a reflex hammer (percussion myotonia). In patients, muscle stiffness lessens with exercise, a change known as the warm-up phenomenon. Our goal was to identify the mechanism underlying warm-up and percussion myotonia and to use this information to guide development of novel therapies. To determine these underlying mechanisms, we used a drug to …

Sensorimotor Deficits Following Oxaliplatin Chemotherapy, Jacob Adam Vincent

Browse all Theses and Dissertations

Neurotoxicity is one of the most significant side effects diminishing clinical efficacy and patient quality of life during and following chemotherapy. Oxaliplatin (OX) is a platinum based chemotherapy agent used in the treatment of colorectal cancer. Colorectal cancer currently ranks as the 4th most common cancer, and the majority of patients receive OX as a part of their adjuvant therapy. OX based adjuvant therapies significantly improve 5 year survival rates, however in many cases patients must stop treatment early because of the neurotoxic side effects. OX causes two clinically distinct forms of neurotoxicity. Acutely, within hours and for days following …

Identification Of Novel Ligands And Structural Requirements For Heterodimerization Of The Liver X Receptor Alpha, Shimpi Bedi

Browse all Theses and Dissertations

LXRs, LXRa (NR1H3) and LXRß (NR1H2), are ligand-activated transcription factors that are members of the nuclear receptor superfamily. Oxysterols and nonsteroidal synthetic compounds bind directly to LXRs and influence the expression of LXR dependent genes. The use of murine models and LXR-selective agonists have established the important role of LXRs as sterol sensors that govern the absorption, transport, and catabolism of cholesterol. Upon activation, these receptors have been shown to increase reverse cholesterol transport from the macrophage back to the liver to aid in the removal of excess cholesterol. Not surprisingly, LXR dysregulation is a feature of several human diseases, …

Analytical-Based Methodologies To Examine In Vitro Nanokinetics Of Silver Nanoparticles, Sesha Lakshmi Arathi Paluri

Browse all Theses and Dissertations

Advancements in the nanotechnology have taken a huge leap in 21st century resulting in 1814 consumer products containing nanomaterials. About 47% of these products belong to the health and fitness sector and ~24% utilize silver nanoparticles (AgNPs). Despite the promising biomedical applications of AgNPs (e.g. bone cements, contrasting agents, and drug-carriers), lack of standardized methods for examining their nanokinetics (i.e., Absorption, Distribution, Metabolism, and Elimination (ADMEs)) limit their clinical implementation. The current work addresses this knowledge gap by developing analytical-based approaches for studying in vitro ADMEs of AgNPs. To demonstrate the versatility of these methodologies, two in vitro kidney study …

Dysregulation Of Phospholipase D (Pld) Isoforms Increases Breast Cancer Cell Invasion, Kristen Fite

Browse all Theses and Dissertations

Breast cancer remains the second most prevalent cancer among women in the U.S. with metastatic breast cancer having the worst prognosis. A rapidly proliferating tumor under various stressors will promote phenotypic cellular changes, known as epithelial-to-mesenchymal transition (EMT), which allows cells to begin to invade surrounding tissue, enter the circulatory system, and eventually seed a distant metastatic site. The phospholipase D (PLD) enzymes are critical regulators of cell signaling pathways necessary for cell migration. While the importance of PLD enzymes in cancer cell invasion is well known, clinically applicable methods of PLD inhibition are not yet available. The best-studied isoforms …

Persistent Inward Currents Play A Role In Muscle Dysfunction Seen In Myotonia Congenita, Ahmed Alaa Hawash

Browse all Theses and Dissertations

Myotonia congenita is a rare skeletal muscle channelopathy caused by a reduced chloride channel (ClC-1) current, which results in debilitating muscle hyperexcitability, prolonged contractions, and transient episodes of weakness. The excitatory events that trigger myotonic action potentials in the absence of stabilizing ClC-1 current are not fully understood. My in vitro intracellular recordings from a mouse homozygous knockout of ClC-1 revealed a slow after-depolarization (AfD) that triggers myotonic action potentials. The AfD is well-explained by a tetrododoxin-sensitive and voltage-dependent Na+ persistent inward current (NaPIC). Notably, this NaPIC undergoes slow inactivation over seconds, thus providing the first mechanistic explanation for the …

A Novel System For Detection Of Dna Double Strand Breaks And Repair In Human Cells, Todd Warren Lewis

Browse all Theses and Dissertations

Imperative to genomic stability is the ability of the cell to repair damaged DNA which can occur from numerous endogenous byproducts of metabolism or exogenous components from the environment. The Fanconi anemia pathway is a DNA repair mechanism used by human cells to resolve multiple forms of DNA damage including interstrand crosslinks (ICL). Fanconi anemia (FA) is an autosomal recessive inherited disorder characterized by genome instability, developmental abnormalities, cancer predisposition and bone marrow failure. FA is attributed to a mutations in at least 18 genes (FANCA-FANCT) that play a concerted role in DNA repair. FANCT is the latest discovery in …

Identifying The Impact Of Noise On Anomaly Detection Through Functional Near-Infrared Spectroscopy (Fnirs) And Eye-Tracking, Ryan Dwight Gabbard

Browse all Theses and Dissertations

Occupational noise frequently occurs in the work environment in military intelligence, surveillance, and reconnaissance (ISR) operations. This impacts cognitive performance by acting as a stressor, potentially interfering with the analysts' decision making process. In this study the effects of different noise stimuli on analysts' performance and workload in anomaly detection were investigated by simulating a noisy work environment. Functional near infrared spectroscopy (fNIRS) was utilized to quantify oxy-hemoglobin (HbO) and deoxy-hemoglobin (HbD) concentration changes in the prefrontal cortex (PFC), as well as behavioral measures which include eye-tracking, reaction time, and accuracy rate. It was found that HbO for some of …

Functions Of The Apical Na+/ K+/ 2cl- Cotransporter 1 In Choroid Plexus Epithelial Cells, Jeannine Marie Crum Gregoriades

Browse all Theses and Dissertations

Choroid plexus epithelial cells (CPECs) secrete cerebrospinal fluid (CSF) and regulate its electrolyte composition. CPECs express both the Na+/ K+ ATPase and the Na+/ K+/ 2Cl- cotransporter 1 (NKCC1) on their apical membrane (CSF facing), deviating from the typical basolateral membrane location in chloride secretory epithelia. Given this unusual location of NKCC1 and the unknown intracellular Na+ and Cl- concentrations of CPECs, the cotransporter function in these cells is not understood. Further, the direction of net ion and associated water fluxes mediated by NKCC1 under basal physiological conditions in CPECs is controversial. Determining the direction of NKCC1- mediated fluxes is …