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Full-Text Articles in Anatomy

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 …


Effect Of Amputation On Muscle Structure Properties In A Rabbit Model, Roy Caleb Stubbs May 2023

Effect Of Amputation On Muscle Structure Properties In A Rabbit Model, Roy Caleb Stubbs

Masters Theses

After amputation, muscles in the residual limb are detached from their insertion points and no longer span the missing joints. Our objective was to quantify the effect of amputation-induced disuse on residual muscle structure, an indirect indicator of muscle force-generating capacity. One hind paw was surgically removed at the ankle joint of ten rabbits. At two weeks (n=5) and 4 weeks (n=5) post-amputation and for select muscles (gastrocnemius, soleus, tibialis cranialis, extensor digitorum, and flexor digitorum superficialis), we measured and computed several muscle structure properties. Additionally, we qualitatively assessed the muscle fiber appearance of histological samples at each timepoint. At …


Material Characterization Of Thermoplastic Polyurethane (Tpu) And Thermoplastic Elastomers (Tpe) For Development Of 3d-Printed Surrogate Organs For Medical Training, Anastasia Elizabeth Lucci Jan 2023

Material Characterization Of Thermoplastic Polyurethane (Tpu) And Thermoplastic Elastomers (Tpe) For Development Of 3d-Printed Surrogate Organs For Medical Training, Anastasia Elizabeth Lucci

Graduate Theses, Dissertations, and Problem Reports

Cadaveric specimens are a necessary, albeit limited, resource for training medical students on basic surgical skills. The availability of surrogate 3D-printed organs would readily allow access to resources that could reduce or potentially eliminate the need for cadaveric specimens or, at a minimum, provide students the opportunity to practice with 3D-printed surrogates before transitioning to those specimens. This research focuses on determining which thermoplastic material most closely mimics mechanical properties such as hardness and stiffness of human organs and allows 3D printing surrogate organs to be used as safe, educational tools. Relatively “soft” materials such as thermoplastic polyurethanes (TPU) and …


Alternative Fixation Of Venous Valves For Bioprosthetic Applications, Makenzie Kapales May 2022

Alternative Fixation Of Venous Valves For Bioprosthetic Applications, Makenzie Kapales

Biomedical Engineering Undergraduate Honors Theses

Venous valve failure allows for the retrograde, or backward, flow of blood into the lower extremities, which leads to Chronic Venous Insufficiency (CVI). CVI infringes upon quality of life through ulceration and can result in death due to Deep Vein Thrombosis (DVT), or blood clots, causing pulmonary embolism. A successful treatment of CVI restores valve function and prevents retrograde blood flow; however, current bioprosthetic venous valves exhibit low patency and high calcification. To improve upon bioprosthetic venous valves and CVI treatment, the University of Arkansas’s Cardiovascular Biomechanics Lab conducts studies with the purpose of comparing the properties and performance of …


Visuomotor Adaptation During Asymmetric Walking, Charles Napoli Oct 2021

Visuomotor Adaptation During Asymmetric Walking, Charles Napoli

Masters Theses

Necessary for effective ambulation, head stability affords optimal conditions for the perception of visual information during dynamic tasks. This maintenance of head-in-space equilibrium is achieved, in part, by the attenuation of the high frequency impact shock resulting from ground contact. While a great deal of experimentation has been done on the matter during steady state locomotion, little is known about how head stability or dynamic visual acuity is maintained during asymmetric walking.

In this study, fifteen participants were instructed to walk on a split-belt treadmill for ten minutes while verbally reporting the orientation of a randomized Landolt-C optotype that was …


Design And Control Of A Peristaltic Pump To Simulate Left Atrial Pressure In A Conductive Silicone Model, Jeremy Collins May 2021

Design And Control Of A Peristaltic Pump To Simulate Left Atrial Pressure In A Conductive Silicone Model, Jeremy Collins

Mechanical Engineering Undergraduate Honors Theses

According to the CDC, atrial fibrillation is responsible for more than 454,000 hospitalizations and approximately 158,000 deaths per year. A common treatment for atrial fibrillation is catheter ablation, a process in which a long flexible tube is guided through the femoral artery and to the source of arrhythmia in the heart, where it measures the electrical potential at various locations and converts problematic heart tissue to scar tissue via ablation. This paper details the design and control of a low-cost ($400) peristaltic pump system using repetitive control to replicate blood pressure in the left atrium in a conductive silicone model …


Nebulizer-Based Systems To Improve Pharmaceutical Aerosol Delivery To The Lungs, Benjamin M. Spence Jan 2021

Nebulizer-Based Systems To Improve Pharmaceutical Aerosol Delivery To The Lungs, Benjamin M. Spence

Theses and Dissertations

Combining vibrating mesh nebulizers with additional new technologies leads to substantial improvements in pharmaceutical aerosol delivery to the lungs across therapeutic administration methods. In this dissertation, streamlined components, aerosol administration synchronization, and/or Excipient Enhanced Growth (EEG) technologies were utilized to develop and test several novel devices and aerosol delivery systems. The first focus of this work was to improve the poor delivery efficiency, e.g., 3.6% of nominal dose (Dugernier et al. 2017), of aerosolized medication administration to adult human subjects concurrent with high flow nasal cannula (HFNC) therapy, a form of continuous-flow non-invasive ventilation (NIV). The developed Low-Volume Mixer-Heater (LVMH) …


An Investigation On The Influences Of Radial Head Hemiarthroplasty Stem Fixation Techniques On Articular Mechanics, Jakub Szmit Nov 2020

An Investigation On The Influences Of Radial Head Hemiarthroplasty Stem Fixation Techniques On Articular Mechanics, Jakub Szmit

Electronic Thesis and Dissertation Repository

Radial head hemiarthroplasty design has been extensively studied with a focus on utilizing the geometrical characteristics of the native radial dish as a guide of implant placement and design. Although implant design has been studied, optimal radial head implant fixation technique remains unknown. This thesis focused on the effect of stem fit on radiocapitellar contact mechanics, using both finite element and experimental bench-top approaches. Additionally, investigation into the impact of varus/valgus malalignment of the radial head in both the native state and following hemiarthroplasty was conducted. It was found that loose fitting a smooth stem axisymmetric radial head implant through …


Evaluation Of Tracing Techniques In The Rat Spinal Cord Using A Custom Matlab Application., Rachel M. Zalla May 2020

Evaluation Of Tracing Techniques In The Rat Spinal Cord Using A Custom Matlab Application., Rachel M. Zalla

Electronic Theses and Dissertations

The objective of this research project is to evaluate the efficiency of traditional chemical tracing compared to dual-viral tracing for labeling long ascending propriospinal neurons (LAPNs) in the uninjured rat spinal cord, and to develop a MATLAB program which will accurately quantify this labeling.

To evaluate chemical tracing, Fluoro-Ruby (FR) was injected at the level of the axon terminals, and the number of ipsilateral labeled cell bodies at lumbar level was quantified. Similarly, two dual-viral systems were evaluated, by either injecting retro-AAV-Cre or HiRet-Lenti-Cre unilaterally in combination with a Cre-dependent adeno-associated virus. The HiRet-Lenti and FR groups labeled significantly greater …


The Of Application Of 3d-Printing To Lumbar Spine Surgery, Andrew J. Kanawati Apr 2020

The Of Application Of 3d-Printing To Lumbar Spine Surgery, Andrew J. Kanawati

Electronic Thesis and Dissertation Repository

Rapid prototyping refers to the manufacturing process in which a three-dimensional (3D) digital model can be transformed into a physical model by layering material in the shape of successive cross sections atop of previously layers. Rapid prototyping has been increasing in popularity in the field of medicine and surgery due to the ability to personalize various aspects of patient care. The thesis will explore the use of rapid prototyping in lumbar spine surgery, aim to quantify the accuracy of medical imaging when relating to imaged structures and their corresponding models produced by rapid prototyping, and determine if complex patient-specific guides …


Enhancement Of The Syncardia Total Artificial Heart For Pediatric Use, Margaret Clark, Madison Marks Jan 2020

Enhancement Of The Syncardia Total Artificial Heart For Pediatric Use, Margaret Clark, Madison Marks

Williams Honors College, Honors Research Projects

Pediatric patients with disorders and diseases of the heart have limited options with regards to implantable devices. Many of these implants are ventricular assist devices, which is not always suitable for a patient. Total artificial hearts (TAHs) have supported many adult patients until transplantation, and we believe that they could do the same for pediatric patients. SynCardia has the only Food and Drug Administration (FDA) approved TAH devices. Since SynCardia is the only company with FDA approved TAHs, we decided to modify the design of the SynCardia TAH for use in pediatric patients without compromising the function of the current …


Artificial Reverse Shoulder Arthroplasty Joint Project, Michael Rosen, Bailei Hoyng Jan 2020

Artificial Reverse Shoulder Arthroplasty Joint Project, Michael Rosen, Bailei Hoyng

Williams Honors College, Honors Research Projects

This proposed project will be developing an artificial reverse shoulder arthroplasty joint that focuses on improvements to the Zimmer Biomet Comprehensive Reverse System by freating a unique feature, or features, to the humeral component that focuses on the prevention of dislocation by not limiting the range of motion of men from ages 45 to 65 years.

The development of the this project will utilize the Food and Drug Administration (FDA) medical device design process. This project will involve a total of four Biomedical Engineering students from the University of Akron. Two students, Michael and Bailei, are in the Honors college …


Using Peripheral Venous Pressure Waveforms To Predict Key Hemodynamic Parameters, Ali Zohair A Alalawi May 2019

Using Peripheral Venous Pressure Waveforms To Predict Key Hemodynamic Parameters, Ali Zohair A Alalawi

Graduate Theses and Dissertations

Analysis of peripheral venous pressure (PVP) waveforms is a novel method of monitoring intravascular volume. Two cohorts were used to study the hemodynamics change of the body state and its influence on the PVP using (1) dehydration setting with infants suffering from pyloric stenosis and (2) hemorrhage setting during a craniosynostosis elective surgery. The goal of this research is to develop a minimally invasive method of analyzing the PVP waveforms and find correlations with volume loss.

Twenty-three pyloric stenosis patients PVP were acquired at five stages and were divided into euvolemic, normal fluid volume, and hypovolemic, significant fluid loss. Seven …


Improving Material Mapping In Glenohumeral Finite Element Models: A Multi-Level Evaluation, Nikolas K. Knowles Apr 2019

Improving Material Mapping In Glenohumeral Finite Element Models: A Multi-Level Evaluation, Nikolas K. Knowles

Electronic Thesis and Dissertation Repository

An improved understanding of glenohumeral bone mechanics can be elucidated using computational models derived from computed tomography data. Although computational tools, such as finite element analysis, provide a powerful quantitative technique to evaluate and answer a variety of biomechanical and clinical questions, glenohumeral finite element models (FEMs) have not kept pace with improvements in modeling techniques or model validation methods seen in other anatomic locations. The present work describes the use of multi-level computational modeling to compare, develop and validate FEMs of the glenohumeral joint.

Common density-modulus relationships within the literature were evaluated using a multi-level comparative testing methodology to …


Acromial Insufficiency Fractures In Reverse Total Shoulder Arthroplasty: A Biomechanical Study, Alicia Kerrigan Dec 2018

Acromial Insufficiency Fractures In Reverse Total Shoulder Arthroplasty: A Biomechanical Study, Alicia Kerrigan

Electronic Thesis and Dissertation Repository

Reverse total shoulder arthroplasty (RTSA) is increasingly utilized in the aging population, with a growing list of surgical indications including rotator cuff tear arthropathy, proximal humerus fractures, and revision arthroplasty. Acromial insufficiency fractures following RTSA are poorly understood, difficult to diagnose, and associated with inferior clinical outcomes. There is limited knowledge in the literature regarding the etiology of post-operative acromial fractures. The purpose of this study is to evaluate the role of implant parameters on acromial strain following RTSA.

Using a cadaveric model, a custom designed modular RTSA system was implanted that allowed for evaluation of modifiable parameters including glenoid …


Tibiotalar Arthrodesis: Development Of A Novel Jig And Alignment Guide, Adam Mathew Ropchan Nov 2018

Tibiotalar Arthrodesis: Development Of A Novel Jig And Alignment Guide, Adam Mathew Ropchan

Electronic Thesis and Dissertation Repository

Tibiotalar arthrodesis is a surgical procedure, used for the treatment of end-stage ankle arthrosis and instability. There are dozens of described procedures in the literature, all with varying rates of success. Two of the most common reasons for reoperation in tibiotalar arthrodesis are nonunion and infection; few studies have established any associations between patient/surgical factors and reoperation for nonunion and infection.

The first part of this thesis focuses on determining the rate of reoperation to the ipsilateral lower limb and if any patient/surgical factors are associated with reoperation for nonunion and infection. The second part of this thesis turns attention …


A Biomechanical Simulation Of Musculoskeletal Kinematics During Ambulation, Alex Thomas Jul 2018

A Biomechanical Simulation Of Musculoskeletal Kinematics During Ambulation, Alex Thomas

Master's Theses (2009 -)

The purpose of this study was to validate a 3D musculoskeletal model in OpenSim and assess OpenSim’s ability to determine muscle-length variation during ambulation. An 18 camera motion capture system was used to analyze 20 healthy individuals between the ages of 18 and 35. Following data collection, the data was processed through OpenSim and Visual3D. The kinematic output processed through the OpenSim model was then compared to the kinematic output of the validated Visual3D model to validate the OpenSim model. Muscle fiber length data obtained from the same experimental data was compared to control data to assess OpenSim’s muscle analysis …


In-Vitro Simulation Of Acute Ischemic Stroke, Paolo Garcia May 2018

In-Vitro Simulation Of Acute Ischemic Stroke, Paolo Garcia

Biomedical Engineering Undergraduate Honors Theses

Acute ischemic stroke (AIS) is a condition that involves the occlusion of a blood vessel within the brain, effectively preventing the passage of oxygen and nutrients. AIS is highly prevalent in the United States, where nearly 795,000 strokes happen per year and 87% of those are ischemic. From a medical standpoint, the obstructing clot can be removed with the use of a stroke retrieval device. However, a need arises for testing the aforementioned devices on a patient’s specific vascular geometries in order to increase the likelihood of a successful procedure. Outlined is a process for developing a physical simulation of …


Comparison Of Varying Tissue Freezing Methods On Murine Colonic Tissue, James Hughes May 2018

Comparison Of Varying Tissue Freezing Methods On Murine Colonic Tissue, James Hughes

Biomedical Engineering Undergraduate Honors Theses

Histology often requires a tissue specimen to be embedded so that it may be sectioned, stained, and mounted on a microscope slide for viewing. One common method of tissue embedding for rapid histology is freezing, since freezing allows tissue to be stored without the need for fixing. Frozen tissue is often embedded in a medium such as Optimal Cutting Temperature (OCT) compound so that it can be sectioned using a cryostat. However, factors such as ice-crystal formation during the freezing process can cause damage to the tissue. As such, the protocol used to freeze the tissue can affect the quality …


Muscle Coordination Contributes To Function After Stroke; Proprioception Contributes To Control Of Posture, Movement, Maria Bengtson Oct 2017

Muscle Coordination Contributes To Function After Stroke; Proprioception Contributes To Control Of Posture, Movement, Maria Bengtson

Dissertations (1934 -)

More than half of stroke survivors experience persistent upper extremity motor impairments that can negatively impact quality of life and independence. Effective use of the upper extremity requires coordination of agonist/antagonist muscle pairs, as well as coordination of multiple control actions for stabilizing and moving the arm. In this dissertation, I present three studies in which I recorded isometric torque production, single joint movement and stabilization, and clinical measures of function and impairments after stroke to evaluate the extent to which changes in coordination of agonist/antagonist muscles and of sequential control actions contribute to deficits after stroke. In Aim 1, …


Nanocellulose Fibers As A Potential Material For Orthopedic Implantation Application, David Gregg Holomakoff Aug 2017

Nanocellulose Fibers As A Potential Material For Orthopedic Implantation Application, David Gregg Holomakoff

Electronic Theses and Dissertations

The field of biomaterials is of immense importance and will continue to grow and develop in the coming years. Novel materials, as well as new approaches for use of existing materials, are sought after now more than ever. Current metal orthopedic implants have an over engineered stiffness and Young’s modulus, causing a phenomenon called stress shielding. Metal implants absorb the majority of force typically exerted on bone and the osteocytes within. When osteocytes fail to sense mechanical forces bones become less dense and weaken, causing possible fracture and other complications. A new orthopedic material is needed matching Young’s modulus of …


Biomechanical Testing Of An Exercise For Strengthening The Proximal Femur., Alyssa Osbourne Aug 2017

Biomechanical Testing Of An Exercise For Strengthening The Proximal Femur., Alyssa Osbourne

Electronic Theses and Dissertations

Based on the principles of cutting edge bone remodeling research, a unique therapeutic exercise device was designed specifically to improve bone quality at the most critical location of the proximal femur prone to fracture: the superior-lateral femoral neck where the fracture first initiates during a fall. The exercise/device is intended to work by inducing enough strain in the bone to stimulate the body’s natural bone remodeling mechanisms to increase bone density in the proximal femur and consequently prevent a fracture from arising if a fall to the side does occur.

In order to test the proposed exercise, experiments simulating the …


Markerless Radiostereogammetry Of The Shoulder Joint In Humans: Comparisons Of Scapulohumeral Kinematics Between Individuals With Healthy And Supraspinatus-Impaired Shoulders, Ashley N. Hannon Apr 2016

Markerless Radiostereogammetry Of The Shoulder Joint In Humans: Comparisons Of Scapulohumeral Kinematics Between Individuals With Healthy And Supraspinatus-Impaired Shoulders, Ashley N. Hannon

Electronic Thesis and Dissertation Repository

The purpose of this collection of studies was to further develop the knowledge of shoulder motion in order to better understand joint function through direct measurement of 3D scapulohumeral joint kinematics using a technique of high accuracy. Markerless, bi-planar fluoroscopic radiostereometric analysis using a generic shoulder model was developed in this thesis, reducing the amount of radiation exposure to subjects. The studies compared kinematic data of the scapulohumeral joint in six degrees of freedom with a precise, in-vivo measuring technique. Data were collected on young and older healthy individuals, individuals with a torn supraspinatus and post-surgical intervention.

Although this generic …


Image-Based 3d Morphometric Analysis Of The Clavicle Intramedullary (Im) Canal, Jazmine Aira Mar 2016

Image-Based 3d Morphometric Analysis Of The Clavicle Intramedullary (Im) Canal, Jazmine Aira

USF Tampa Graduate Theses and Dissertations

Midshaft clavicle fractures are very common. Current treatment of choice involves internal fixation with superior or anterior clavicle plating, however their clinical success and patient satisfaction are slowly decreasing. The design of intramedullary (IM) devices is on the rise, but data describing the IM canal parameters is lacking. The aim of this study is to quantify morphometry of the clavicle and its IM canal, and to evaluate the effect of gender and anatomical side. This study used 3-dimensional (3D) image-based models with novel and automated methods of standardization, normalization and bone cross-section evaluation. The data obtained in this thesis presents …


Biventricular Finite Element Modeling And Quantification Of 3d Langragian Strains And Torsion Using Dense Mri, Zhanqiu Liu Jan 2016

Biventricular Finite Element Modeling And Quantification Of 3d Langragian Strains And Torsion Using Dense Mri, Zhanqiu Liu

Theses and Dissertations--Mechanical Engineering

Statistical data suggests that increased use of evidence-based medical therapies has largely contributed to the decrease in American death rate caused by heart disease. And my studies are about two applications of magnetic resonance imaging (MRI) as a non-invasive approach in evidence-based health care research. In my first study, the achievement of a pulmonary valve replacement surgery was assessed on a patient with tetralogy of Fallot (TOF). In order to evaluate the remodeling of right ventricle, two biventricular finite element models were built up for pre-surgical images and post-surgical images. In my second study, 3D Lagrangian strains and torsion in …


An Algorithm For Extracting The Ppg Baseline Drift In Real-Time, Tuan Ngoc Nguyen Jan 2016

An Algorithm For Extracting The Ppg Baseline Drift In Real-Time, Tuan Ngoc Nguyen

Theses: Doctorates and Masters

Photoplethysmography is an optical technique for measuring the perfusion of blood in skin and tissue arterial vessels. Due to its simplicity, accessibility and abundance of information on an individual’s cardiovascular system, it has been a pervasive topic of research within recent years. With these benefits however there are many challenges concerning the processing and conditioning of the signal in order to allow information to be extracted. One such challenge is removing the baseline drift of the signal, which is caused by respiratory rate, muscle tremor and physiological changes within the body as a response to various stimuli.

Over the years …


The Effect Of Neurostimulation On Ischemic Pain And Methods Of Assessing Pain, Kaylee Keck Dec 2015

The Effect Of Neurostimulation On Ischemic Pain And Methods Of Assessing Pain, Kaylee Keck

Biomedical Engineering

Peripheral arterial disease (PAD) impacts approximately eight million people in the United States [1]. Disease progression leads to chronic ischemic pain, hindering quality of life. Pharmaceuticals are a typical treatment for pain associated with PAD; but as few as 30% of patients have a significant reduction of pain (≥50%) [2].

Neurostimulation is commonly used as a treatment for various diseases and injuries, including Parkinson’s disease and sports-related back and knee injuries [2]. The objective of the study was to explore neurostimulation and its effect on pain and paresthesia for a model of acute peripheral ischemia in young college students.

Pain …


Mimicking The Arterial Microenvironment With Peg-Pc To Investigate The Roles Of Physicochemical Stimuli In Smc Phenotype And Behavior, William G. Herrick Aug 2015

Mimicking The Arterial Microenvironment With Peg-Pc To Investigate The Roles Of Physicochemical Stimuli In Smc Phenotype And Behavior, William G. Herrick

Doctoral Dissertations

The goal of this dissertation was to parse the roles of physical, mechanical and chemical cues in the phenotype plasticity of smooth muscle cells (SMCs) in atherosclerosis. We first developed and characterized a novel synthetic hydrogel with desirable traits for studying mechanotransduction in vitro. This hydrogel, PEG-PC, is a co-polymer of poly(ethylene glycol) and phosphorylcholine with an incredible range of Young’s moduli (~1 kPa - 9 MPa) that enables reproduction of nearly any tissue stiffness, exceptional optical and anti-fouling properties, and support for covalent attachment of extracellular matrix (ECM) proteins. To our knowledge, this combination of mechanical range, low …


Computational Modeling To Assess Surgical Procedures For The Treatment Of Adult Acquired Flatfoot Deformity, Brian A. Smith Jan 2015

Computational Modeling To Assess Surgical Procedures For The Treatment Of Adult Acquired Flatfoot Deformity, Brian A. Smith

Theses and Dissertations

Several surgically corrective procedures are considered to treat Adult Acquired Flatfoot Deformity (AAFD) patients, relieve pain, and restore function. Procedure selection is based on best practices and surgeon preference. Recent research created patient specific models of Adult Acquired Flatfoot Deformity (AAFD) to explore their predictive capabilities and examine effectiveness of the surgical procedure used to treat the deformity. The models’ behavior was governed solely by patient bodyweight, soft tissue constraints, and joint contact without the assumption of idealized joints. The current work expanded those models to determine if an alternate procedure would be more effective for the individual. These procedures …


Target-Directed Biosynthetic Evolution: Redirecting Plant Evolution To Genomically Optimize A Plant’S Pharmacological Profile, Dustin Paul Brown Jan 2015

Target-Directed Biosynthetic Evolution: Redirecting Plant Evolution To Genomically Optimize A Plant’S Pharmacological Profile, Dustin Paul Brown

Theses and Dissertations--Neuroscience

The dissertation describes a novel method for plant drug discovery based on mutation and selection of plant cells. Despite the industry focus on chemical synthesis, plants remain a source of potent and complex bioactive metabolites. Many of these have evolved as defensive compounds targeted on key proteins in the CNS of herbivorous insects, for example the insect dopamine transporter (DAT). Because of homology with the human DAT protein some of these metabolites have high abuse potential, but others may be valuable in treating drug dependence. This dissertation redirects the evolution of a native Lobelia species toward metabolites with greater activity …