Engineering Commons^™

Effect Of Dimensionality On In Vitro Growth Environment And Mesenchymal Stem Cell Function, Fatema Tuj Zohora

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The use of the standard two dimensional (2D) cell culture has laid down the fundamentals of molecular and cell biology. However, recent advances in cell-based regenerative medicine raises the concern on deconstructing cellular behaviors in more physiologically relevant three dimensional (3D) microenvironments. Differences in cell response in 2D versus 3D systems arise from the perturbations in gene expression patterns that stem from how cells sense their underlying 2D or surrounding 3D matrices and adjust their phenotypes accordingly. Thus, cells are no longer considered as a solitary entity of genome but a context arises from a combinatorial interactions of cell-ECM, cell-cell, …

A Framework For Centralizing Inventory In Pharmaceutical Supply Chains, Kerry Kathleen Ward

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Effectively choosing the location of inventory in a pharmaceutical supply chain is central to the mission of pharmaceutical distributors. These supply chains are a critical backbone to the healthcare delivery process: the distributors must deliver products to pharmacies, hospitals and retailers at low cost and with a high level of reliability. This thesis provides a method for analyzing demand data to gain insight on the value of centralizing the inventory into either a hub-and-spoke or national network for a pharmaceutical distribution company. Demand data is analyzed using an off-the-shelf analysis tool as well as a new tool developed in SQL …

Assessing Effectiveness Of Information Presentation Using Wearable Augmented Display Device For Emergency Response, Sriram Raju Chandran

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Small screen wearable devices are becoming ubiquitous in the medical field; especially in the fields of surgery and trauma care. Technological intervention that supports data transfer of sending summary of the patient vitals through the transfer of care would be of great benefit to trauma care department. This research focuses on information presentation for wearable augmented reality device to improve human decision making during transfer of care for emergency response, and to improve user experience and reduce cognitive workload. Google Glass ™ device acts as heads up display for users, in this case being medical responders in hospital trauma care. …

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

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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 …

Implicit Leadership And Followership Theories: Does Congruency Matter?, Daniel Bashore

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Leadership research largely has ignored the extent to which followers influence leaders and the leadership process. Even fewer studies have examined the effect of Implicit Leadership Theories (ILTs) and Implicit Followership Theories (IFTs) on performance and affective outcomes. In prior research, there is an implicit assumption that ILTs and IFTs are compatible, but little research has examined the presence of incongruent ILTs and IFTs and potential effects incongruence might have on organizational outcomes. The current study examined the effect of ILT/IFT congruence on organizational outcomes (performance, satisfaction, and perceived leader effectiveness) in two different samples: a student sample (N = …

Evaluating Mobile Information Display System In Transfer Of Care, Katelyn Berberich

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Transfer of care continuum is highly dynamic in nature and there are multiple complexities associated with man-man interaction and man-machine interaction. During transfer of patient care, which occurs from an emergency medical team (EMT) to an emergency department, adequate information related to the patient must be communicated very quickly and precisely. Challenges EMTs and emergency department personnel face are communicating and obtaining all the essential information to ensure the patient receives the best care. Providing the receiving emergency department with patient vitals and pre-hospital procedures that occurred en route could allow for enhanced preparation and improved communication during the transfer …

Characterization Of Peripheral Lung Lesions By Statistical Image Processing Of Endobronchial Ultrasound Images, Aaron T. Madaris

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This thesis introduces the concept of implementing greyscale analysis, also known as intensity analysis, on endobronchial ultrasound (EBUS) images for the purposes of diagnosing peripheral lung tumors. The statistical methodology of using greyscale and histogram analysis allows the characterization of lung tissue in EBUS images. Regions of interest (ROI) will be analyzed in MATLAB and a feature vector will be created. A feature vector of first-order, second-order and histogram greyscale analysis will be created and used for the classification of malignant vs benign peripheral lung tumors. The tools that were implemented were MedCalc for the initial statistical analysis of receiver …

Analyzing Cognitive Workload Through Eye-Related Measurements: A Meta-Analysis, Melissa Patricia Coral

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Understanding cognitive workload has become a vital topic for researchers in developing future systems. Existing research has investigated the use of physiological measurements of the eye with cognitive workload, though a quantitative synthesis has yet to be performed. A meta-analysis was conducted to examine the effects of cognitive workload on eye-related measurements. The objective of this meta-analysis is not to determine a difference between the levels of workload, but to identify reliable measurements. Measurements through blinks, saccades, pupils, and fixations were examined. Twenty-two studies, contributing to a total of sixty entries, met the appropriate inclusion criteria for the meta-analysis. Findings …

Low-Cost, Wireless Optical Oximeter For Monitoring Of Brain Function In High-Risk Pediatric Population, Zahra Meghjani

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Nearly 4 million neonates die every year due to brain injuries, most caused by hypoxia. Neonatal ICU requires newborns with critical health conditions to be monitored continuously calling for the need of a non-invasive, compact and portable device. However, commercial devices are mostly bulky and/or expensive. The neonatal mortality is higher in under-developed countries, where such expensive and large devices are not affordable. Hence, my thesis focuses on building first generation compact, inexpensive, and wireless device that can monitor and provide feedback to clinicians during intervention. This approach is based on light absorption by oxy- and deoxy-hemoglobin chromophores. The total …

A Fractal-Based Mathematical Model For Cancellous Bone Growth Considering The Hierarchical Nature Of Bone, Stephanie Marie Suhr

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The hierarchical structure of bone alone is not comprehensive enough to provide morphological explanation of how the size and arrangement of the trabeculae within cancellous bone affect load distribution, particularly concerning deterioration of bone in elderly patients. The collagen network and hydroxyapatite play a large role in defining the shape of trabeculae in cancellous bone despite that the arrangement and size is seemingly random. The growth of plates and rods in cancellous bone is mainly due to loading and stress lines within the bone, but mathematical predictive models can be developed using fractal analysis to show how bone may grow …

Optical Redox Imaging Of Metabolic Activity, Syed Anwar Hyder Zaidi

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Fluorescence imaging can be used to determine tissue metabolism, which is an indication of the cellular functionality. Metabolic contrast is useful for the early detection of several medical conditions such as cancer, diabetes, lung diseases etc. This study aims to use fluorescence imaging to quantify NADH and FAD, which are cellular metabolic indicators. A parameter known as Redox ratio, can be used to study metabolic state of several tissue types and disease states. To quantify the Redox ratio, three fluorescence imaging systems were optimized to measure the fluorescence signal from NADH and FAD. The first system was a camera based …

Early Assessment Of Burn Severity In Human Tissue With Multi-Wavelength Spatial Frequency Domain Imaging, Chien Sing Poon

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Burn injuries such as thermal burns, which are caused by contact with flames, hot liquids, hot surfaces, and other sources of high heat as well as chemical burns and electrical burns, affects at least 500,000 people in the United States, to which 45,000 of them require medical treatment and 3,500 of them result in death. It has also been reported that in the United States alone, fire results in a death approximately every three hours and an injury every 33 minutes. Early knowledge about burn severity can lead to improved outcome for patients. In this study, the changes in optical …

Comparison Of Vascular Pulsatility In The Native Beating Heart Versus Direct Mechanical Ventricular Actuation Support Of The Fibrillating Heart, Nathan Victor Wright

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Most conventional cardiac assist devices today employ continuous flow blood pumps to supplement function in the dysfunctional heart. Continuous flow pumps are predominantly preferred to the original pulsatile pumps due to the smaller size (greater implantability) and higher efficiency they achieve. However, interest in the impact of vascular pulsatility on human health has arisen from the growing evidence of higher complications with nonpulsatile devices compared to pulsatile devices. Direct cardiac compression (DCC) offers a unique solution to the pulsatility issue through the application of force directly to the heart's surface. It is believed that employing the existing pump architecture of …

Improving Anomaly Detection Through Identification Of Physiological Signatures Of Unconscious Awareness, Alyssa Marie Piasecki

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Missed anomalies have the potential to cause detrimental effects in the Intelligence, Surveillance, and Reconnaissance (ISR) domain. One possible cause of these missed anomalies is that cognitive processing may not reach conscious awareness and may only be perceived by the unconscious mind. Identification of correlates of these unconscious processes could provide an insight into potential missed targets. The present study explored missed anomalies in a visual search task and the possibility of unconscious awareness. Eye metrics were recorded and a "Detection Threshold Model" was created and validated with a nominal logistic regression model, in order to characterize the search patterns …

Use Of Eeg To Understand Brain Intensity In Engineering Students Using A Stem Educational Mobile Application, Kevin Hatcher

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In the first two years of undergraduate work in engineering, students are taught concepts such as physics, electronics, and most importantly calculus. It is especially important for students to get a better grasp on foundational math concepts, such as calculus in the beginning or they will be overwhelmed by the workload to come. The focus of this research was to understand how students learning calculus, could benefit from an augmented-educational mobile application. In the study students were measured with electroencephalography (EEG) measurements utilized by the Emotive EPOC® as they attempted to solve different limit themed problems in order to determine …

Design And Evaluation Of A Fiber Optic Shape Tracker For Use As A Navigational Aid In Endovascular Guidewires And Catheters, Benjamin Stewart Rinehart

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Endovascular intervention is the current gold-standard for screening and treating aortic aneurysms and complications caused by peripheral vascular disease (PAD). A typical endovascular procedure begins with inserting an endovascular guidewire into the femoral artery via incision. A catheter is then threaded over the guidewire and both tools are then navigated to the treatment site. The navigation is guided solely by fluoroscopy (x-ray) imagery that is performed throughout the duration of the procedure. Not only does this method provide limited 2-D guidance, but also exposes the patient and medical staff to high levels of radiation. This thesis research focuses on the …

Measuring Pulse Rate Variability During Motion Artifact With A Non-Contact, Multi-Imager Photoplethysmography System, Zachary Adam Kiehl

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Non-contact imaging photoplethysmography is an exciting new field based on the principles of traditional photoplethysmography where viable signals can now be acquired without the use of contact equipment. Recent advances regarding non-contact imaging photoplethysmography have permitted a wide range of new possibilities focused on sensing the cardiopulmonary system. Physiological metrics such as pulse rate, respiration rate, and pulse rate variability can be obtained by current photoplethysmographic imaging methods. Although previous systems were challenged by head-motion artifacts, the mitigation of rigid head-motion artifacts has been demonstrated with a multi-imager design. This study investigated the feasibility and accuracy of pulse rate variability …

Neural Correlates Of Convergence Eye Movements In Convergence Insufficiency Patients Vs Normal Binocular Vision Controls: An Fmri Study, Chirag Bharatkumar Limbachia

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Convergence Insufficiency is a binocular vision disorder, characterized by reduced ability of performing convergence eye movements. Absence of convergence causes, eye strain, blurred vision, doubled vision, headaches, and difficulty reading due frequent loss of place. These symptoms commonly occur during near work. The purpose of this study was to quantify neural correlates associated with convergence eye movements in convergence insufficient (CI) patients vs. normal binocular vision (NBV) controls, and to examine statistical differences between them. Functional magnetic resonance imaging (fMRI) scans were collected using a 3T Siemens scanner. A disparity-driven convergence task was designed using a standard block design approach, …

Left Ventricle Volume Reconstruction To Minimize Scanning Time: Slice-Fitting Method, Prateek Kalra

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Assessment of left ventricle volume is usually done for diagnosis and prognosis of heart diseases. Slice-summation method is a standard method used to compute left ventricle volume where region of interest from several short axis (SA) slices are added. There are some limitations to this method, however. It requires short-axis slices to be taken parallel to the mitral valve plane from the base to apex. Moreover, scanning several short-axis slices is a tedious and time consuming process especially for studies that require several hundreds datasets. There are some existing methods to reconstruct left ventricle volume but most of them depend …

Virtual Agent Interaction - Improving Cognitive Abilities And Trust For A Complex Visual Search Task, Heather H. Milecki

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Introduction: This thesis research examined a novel decision support aid ("Spatial Cue + Virtual Agent") on human performance in a simulated complex visual search task. Method: Participants in the "Control" condition did not receive support from an aid. Participants in the "Spatial Cue" condition received support from an aid in the form of a bounding box. Participants in the "Spatial Cue + Virtual Agent" condition received support from an aid in the form of a bounding box and a virtual agent. The aids' reliability was held constant at one level, 70 percent. Image difficulty was based on clutter; clutter was …

Reducing Error Rates In Intelligence, Surveillance, And Reconnaissance (Isr) Anomaly Detection Via Information Presentation Optimization, Donald Glen Church

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In the ISR domain, time-critical decision-making and dealing with multiple information feeds places high demands on the human. When designing aids and tools, the decision maker must be taken into account. This research looks toward designing a decision aid based the personality type of the operator. The BFI is used to determine the impact of personality and decision aid type (graphical vs. textual) on performance. Results show Openness and Agreeableness to be the strongest single factors for decision aid impact on performance. A model was also developed to show how the human takes the information and relates it to a …

Evaluating Warehouse Strategies For Two-Product Class Distribution Planning, Bradley R. Guthrie

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Distribution networks often manage products with varying life-cycles, where demand for some products is relatively stable throughout the year (basic products) and the demand for others is short-lived (fashion products). Beyond the coordination of inventory and transportation decisions, decisions at the warehouse must be considered as its resources are frequently shared by both product classes simultaneously. For this two-product class distribution planning problem, we focus on characterizing three real-world distribution strategies observed in industry and evaluating them based on total distribution cost and warehouse measures (e.g., workforce plan and workload variation) against a benchmark ILS-based heuristic. Experimental results suggest that …

Design Of A Low-Cost Wireless Nirs System With Embedded Linux And A Smartphone Interface, Diogo Da Silva Dias

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Wireless near-infrared spectroscopy (NIRS) systems can help to reduce movement artifacts, and distraction due cables. Utilizing Embedded Linux (EL) can reduce size, development time, cost of a project and allow portability. The goal of this project is to develop a low-cost wireless small-sized NIRS system using EL and a Smartphone as the interface. This was achieved using a BeagleBone Black (BBB) with a deployed custom EL that: (1) controls two sources, (2) receives data from photodetectors (PDs), (3) processes, stores and transmits data via Bluetooth to an Android Smartphone. This device was implemented in under US$150 and its dimension was …

Measuring Brain Activation Through Functional Magnetic Resonance Imaging (Fmri) During Visual Task Learning, Mohd Saif Usmani

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The purpose of this study is to understand the brain activity associated with learning a visual task by utilizing the applications of functional magnetic resonance imaging in cognitive neuroscience. The study was performed using two visual tasks referred to as aircraft and control, respectively. We compared the brain activation of these two visual tasks to understand the learning process of the participants. Fifteen young adults, ten males and five females, ranging in age from 19 to 35 years, participated in a ten-week study. Eight participants dropped out either voluntarily or were excluded for different reasons. The data analysis was completed …

An Improved Adaptive Filtering Approach For Removing Artifact From The Electroencephalogram, Justin Ronald Estepp

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The biophysics of volume conduction that enable electrophysiological data acquisition also result in the mixing of data sources including possible, undesirable noise sources at the electrode interface. This work specifically focuses on improving the performance of the recursive least-squares (RLS) adaptive filtering method for removing eye movement artifact from the electroencephalogram. In biophysically-inspired simulated data, the RLS algorithm is verified to produce results that are inferior to extended infomax independent component analysis (ICA), the most widely used artifact correction approach in this problem space, due to its non-linear filter phase response and the presence of bidirectional contamination, or cross-talk, resultant …

Investigation Of Cultural Bias Using Physiological Metrics: Applications To International Business, Renee Nicole Rigrish

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In today's world, many business transactions and interactions are conducted cross-culturally. When going to a business meeting, it is essential avoid a major cultural faux pas in order to not offend your business partners. The Cultural Lens model is used to understand the origins of cultural mismatches. An individual must adjust their approach to a situation to create a cultural match. In adjusting this approach, cognitive biases are a potential result in cross-cultural scenarios. We investigate the Mirror Imaging Bias, which has been found to be a common result of a shortcut to decide how to act in a situation. …

Investigation Of Mirror Image Bias: Evidence For The Use Of Psychophysiological Measures As Indicators Of Cognitive Heuristics, Caroline R. Salchak

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The Mirror Imaging Bias (MIB) is gaining attention as a prominent quality factor in analysts' performance. MIB is an irrationality in which analysts perceive and process information through the filter of personal experience. As evidenced by notable historical events, the consequences of this bias can be dramatic. A way to understand MIB in humans is sought. How analysts analyze data, are trained, and interact with biases is explored. An experiment testing for the appearance of MIB was designed and completed. Measures from an eye tracker as well as physiological measures were collected. Results show a significant correlation between pupil diameter …

Investigation Of Capabilities Of Observers In A Watch Window Study, Ositadimma Nnanna Eziolisa

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Due to an abundance of data and dynamic nature of tasks, challenges with information retrieval in surveillance and target identification tasks have risen in today's Intelligence, Surveillance, and Reconnaissance (ISR) community. In this study, two variables, Area of Coverage and Amount of Activity (AOC/ACT), are manipulated to study their effects on the number of Watch Windows an observer can monitor. This research describes the analyst's task model, and explains how the level of AOC/ACT and number of Watch Windows affects the analyst's cognitive load. Results showed a significant difference in performance and physiological indicators of workload between high AOC/ACT conditions …

Development And Application Of An Analyst Process Model For A Search Task Scenario, Hendrickson K. Karl

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A key intelligence analyst role in open source search is the transformation of data into understanding. Better comprehension is needed of how new tools impact the analyst search process. The use of function analysis, heuristic analysis, and a usability study combine to provide the basis for developing an analyst process model, which affords the researcher with a structure to measure the impact of tools and expertise in performing a search task. The experiment utilized representative analyst scenario tasks in comparing baseline tools with the Geospatial Open Search Toolkit (GOST). The results show error rates increase when using a new toolset …

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 …