Biomedical Engineering and Bioengineering Commons^™

The Biomechanical Role Of Scaffolds In Augmented Rotator Cuff Tendon Repairs, Amit Aurora, Jesse A. Mccarron, Antonie J. Van Den Bogert, Jorge E. Gatica, Joseph P. Iannotti, Kathleen A. Derwin

Mechanical Engineering Faculty Publications

Background

Scaffolds continue to be developed and used for rotator cuff repair augmentation; however, the appropriate scaffold material properties and/or surgical application techniques for achieving optimal biomechanical performance remains unknown. The objectives of the study were to simulate a previously validated spring-network model for clinically relevant scenarios to predict: (1) the manner in which changes to components of the repair influence the biomechanical performance of the repair and (2) the percent load carried by the scaffold augmentation component.

Materials and methods

The models were parametrically varied to simulate clinically relevant scenarios, namely, changes in tendon quality, altered surgical technique(s), and …

Analysis Of The Effect Of Feeding Regimen On Gh/Igf Axis In Channel Catfish (Ictalurus Punctatus), Samantha Puckett

Biological and Agricultural Engineering Undergraduate Honors Theses

Channel catfish (Ictalurus punctatus) are the most widely farmed aquatic animal in the United States. Assessing the effect of feeding regimens on their overall growth requires grow-out trials and a subsequent inefficient use of time and money. The growth hormone (GH)/insulin-like growth factor-1 (IGF-1) axis regulates growth based upon environmental factors such as feed intake in many teleost fish species. In order to increase the efficiency of aquaculture, the components of the GH/IGF-1 axis might be used as endocrine biomarkers to evaluate instantaneous growth rate. The goal of this study was to better understand the effects of feeding regimen on …

Experimental Composite Guidance Conduits For Peripheral Nerve Repair: An Evaluation Of Ion Release, X. F. Zhang, A. Coughlan, H. O'Shea, Mark R. Towler, S. Kehoe, D. Boyd

Chemical and Biochemical Engineering Faculty Research & Creative Works

Poly (lactide-co-glycolide) (PLGA) - Pluronic F127 - glass composites have demonstrated excellent potential, from the perspective of controlled mechanical properties and cytocompatibility, for peripheral nerve regeneration. In addition to controlling the mechanical properties and cytotoxicity for such composite devices, the glass component may mediate specific responses upon implantation via degradation in the physiological environment and release of constituent elements. However, research focused on quantifying the release levels of such therapeutic ions from these experimental medical devices has been limited. To redress the balance, this paper explores the ion release profiles for Si⁴⁺, Ca²⁺, Na⁺, …

Changes In In Vivo Knee Contact Forces Through Gait Modification, Allison Kinney, Thor F. Besier, Amy Slider, Scott L. Delp, Darryl D. D'Lima, Benjamin J. Fregly

Mechanical and Aerospace Engineering Faculty Publications

Gait modification represents a non-invasive method for reducing knee joint loading in patients with knee osteoarthritis. Previous studies have shown that a variety of gait modifications are effective in reducing the external knee adduction moment. The external knee adduction moment is often used as a surrogate measure of medial compartment force. However, a recent study showed that reductions in the external knee adduction moment do not guarantee reductions in medial compartment loads. Therefore, direct measurement of changes in knee contact force is important for determining the effectiveness of gait modifications. A previous study found that medial thrust gait and walking …

Measurement Of The Oxidation State Of Mitochondrial Cytochrome C From The Neocortex Of The Mammalian Brain, Y. Sakata, M. Abajian, M. O. Ripple, R. Springett

Dartmouth Scholarship

Diffuse optical remission spectra from the mammalian neocortex at visible wavelengths contain spectral features originating from the mitochondria. A new algorithm is presented, based on analytically relating the first differential of the attenuation spectrum to the first differential of the chromophore spectra, that can separate and calculate the oxidation state of cytochrome c as well as the absolute concentration and saturation of hemoglobin. The algorithm is validated in phantoms and then tested on the neocortex of the rat during an anoxic challenge. Implementation of the algorithm will provide detailed information of mitochondrial oxygenation and mitochondrial function in physiological studies of …

Two-Dimensional Blood Flow Velocity Estimation Using Ultrasound Speckle Pattern Dependence On Scan Direction And Velocity, Tiantian Xu

Department of Agricultural and Biological Systems Engineering: Dissertations, Theses, and Student Research

Cardiovascular disease is the leading cause death in the United States. Although emergency surgery and medicine can be used for cardiovascular disease treatment, the survivors will suffer for it afterwards. Ultrasound blood flow measurement provides a noninvasive way for cardiovascular diseases diagnosis. In this dissertation, three algorithms for blood flow velocity measurements were investigated and optimized. Feature tracking has been previously proposed for vector velocity measurement. In Chapter 3, the optimal amplitude and time thresholds for feature extraction were investigated to minimize flow estimate variance while providing sufficient spatial and temporal coverage of flow area. A new method of lateral …

Gallium Containing Glass Polyalkenoate Anti-Cancerous Bone Cements: Glass Characterization And Physical Properties, A. W. Wren, A. Coughlan, L. Placek, Mark R. Towler

Chemical and Biochemical Engineering Faculty Research & Creative Works

A gallium (Ga) glass series (0.48SiO₂-0.40ZnO-0.12CaO, with 0.08 mol% substitution for ZnO) was developed to formulate a Ga-containing Glass Polyalkenoate Cement (GPC) series. Network connectivity (NC) and X-ray Photoelectron Spectroscopy (XPS) was employed to investigate the role of Ga³⁺ in the glass, where it is assumed to act as a network modifier. Ga-GPC series was formulated with E9 and E11 polyacrylic acid (PAA) at 50, 55 and 60 wt% additions. E11 working times (T_w) ranged from 68 to 96 s (Lcon.) and 106 s for the Ga-GPCs (LGa-1 and LGa-2). Setting times (T_s) …

A Novel Method For Determining Acetabular Orientation, Sean Higgins

Theses and Dissertations

Enhanced knowledge of the acetabulum is of paramount importance in the diagnostic, planning, and execution stages of procedures and treatments targeting the hip joint. The convoluted and highly variable morphology of the structures comprising the bony pelvis make ascertaining measures of the acetabulum challenging. Furthermore, current methods for determining acetabular orientation assume symmetry between the separate halves of the pelvis by utilizing a coordinate system based on bilateral landmarks. The purpose of this study was to determine the three-dimensional orientation of the entire acetabulum. For this research, an improved programmatic method was developed for determining acetabular orientation using three-dimensional data. …

Understanding The In Vivo Uptake Kinetics Of A Phosphatidylethanolamine-Binding Agent 99mTc-Duramycin, Said H. Audi, Zhixin Li, Joseph Capacete, Yu Liu, Wei Fang, Laura G. Shu, Ming Zhao

Biomedical Engineering Faculty Research and Publications

Introduction

^99mTc-Duramycin is a peptide-based molecular probe that binds specifically to phosphatidylethanolamine (PE). The goal was to characterize the kinetics of molecular interactions between ^99mTc-Duramycin and the target tissue.

Methods

High level of accessible PE is induced in cardiac tissues by myocardial ischemia (30 min) and reperfusion (120 min) in Sprague–Dawley rats. Target binding and biodistribution of ^99mTc-duramycin were captured using SPECT/CT. To quantify the binding kinetics, the presence of radioactivity in ischemic versus normal cardiac tissues was measured by gamma counting at 3, 10, 20, 60 and 180 min after injection. A partially inactivated form of …

Storage And Loss Moduli Of Bone In Osteogenesis Imperfecta (Oi), Carolyne Albert, John Jameson, Jeffrey Toth, Peter A. Smith, Gerald F. Harris

Biomedical Engineering Faculty Research and Publications

No abstract provided.

Oral Delivery Of Peptide Drugs For Mitigation Of Crohn's Disease, Paul Blichmann

All Theses

Protein drugs are typically administered intravenously, but this practice has clear disadvantages such as widespread circulation and swift clearance from the body. Orally delivered protein drugs are not yet available but potentially offer improved distribution, retention, and activity by use of protective matrices and cell-specific targeting. Much work has been done on delayed release formulations for the upper intestine, but there has not been overwhelming evidence of protection of peptides from gastric conditions. In many instances the large intestine may be a better release target due to lower proteolytic activity. Afflictions of the colon such as Inflammatory Bowel Disease and …

The Formulation Of A Bone Targeted Drug Delivery System Of Poly(Glycolic Acid)-Poly(Ethylene Glycol) Coated Hydroxyapatite Nanoparticles For The Delivery Of Statins, Erika Jelen

All Theses

Bone is a form of mineralized connective tissue that provides strength and rigidity to the skeleton. The two primary components within bone tissue are an organic extracellular matrix, containing type I collagen, and an inorganic mineral component composed mainly of calcium phosphate hydroxyapatite crystals. Over time the microarchitecture of bone can break down due to a variety of different factors, mainly the onset of osteoporosis in post-menopausal women, Paget's disease, and the experience of a loss of gravity during space flight. Currently there are about ten million people in the United States alone suffering from osteoporosis.
The prevention of further …

The Effect Of A Navigational Aid On Training Of A Minimally Invasive Surgery Camera Task, Ketan Vidwans

Theses and Dissertations

Minimally Invasive Surgery (MIS) differs from Open Surgery as surgeons view the surgical site indirectly on a monitor. The view shown is typically from an angled endoscope off to one side of the surgery (i.e., uncollocated with the view of the hands). This makes camera navigation a challenging ability to learn. MIS thus requires longer training periods, more practice and mental effort to achieve proficiency. Current training setups and Operating Room (OR) environments lack appropriate real-time visual cues for navigation and other perception related information that could help with learning and performance in the OR. The purpose of this research …

Dynamics Of Depression Storage During Sprinkler Irrigation And Precipitation Events, Michael B. Mckinney

Department of Agricultural and Biological Systems Engineering: Dissertations, Theses, and Student Research

Surface depression storage (D_s) is the volume of precipitation excess which is stored by surface microrelief features of soils. The volume of water stored in surface depressions when precipitation rate exceeds infiltration rate reduces the amount of runoff generated. Because Ds is dependent on soil microrelief, land slope, and crop residue, tillage and management practices can have a considerable impact on the magnitude of this value.

When modeling irrigation systems and surface hydrology, depression storage is often treated as a static abstraction, meaning that maximum storage volume must be filled before runoff occurs. However, several researchers have documented …

Evaluation Of A Novel Myoelectric Training Device, Ryan Clingman

Theses and Dissertations

While research shows that a patient’s success in using a myoelectric prosthetic arm is dependent on receiving effective training, current methods of training are not designed to effectively hold attention long enough for optimal training. This study focused on evaluating a novel myoelectric training device, consisting of a toy car controlled by EMG signals from the arm. Subjects’ performance with the trainer was evaluated to determine its ability to provide experience with EMG controls. Eight healthy adult subjects were taken through typical initial stages of myoelectric training, then asked to drive the car through a slalom course while the time, …

Life History Switch Point Plasticy In Response To Pond Drying Alyers Metamorph Allometry And Jumping Performance, Julie Charbonnier

Theses and Dissertations

Animals with complex life cycles can cope with environmental uncertainty by altering life history switch points through developmental plasticity. Pond drying is an important factor which may alter life history switch points in aquatic organisms. Many amphibians can plastically respond to changes in pond drying by emerging earlier, but few studies have examined the post-metamorphic consequences for performance. To investigate the potential carry-over effects of plasticity to pond drying, we studied the túngara frog, Physalaemus pustulosus, a tropical anuran that breeds in highly ephemeral habitats. We conducted a field study with three different water depth treatments in 60 L mesocosms …

Design, Analysis And Testing Of Haptic Feedback System For Laparoscopic Graspers In In Vivo Surgical Robots, Nikhil Salvi

Department of Mechanical and Materials Engineering: Dissertations, Theses, and Student Research

Laparo-Endoscopic Single Site (LESS) Robotics Surgery is an advanced technology in the field of Minimally Invasive Surgery (MIS). The LESS surgical robots significantly improve the surgeon’s accuracy, dexterity and visualization, and reduce the invasiveness of surgical procedure results in faster recovery time and improved cosmetic results. In a standard robotic endosurgery, the palpation of tissues is performed by laparoscopic graspers located at the end effectors. The master-slave configuration in robotic surgery leads in remote access to the operation site. Therefore, surgeon’s ability to perceive valuable sensory information is severely diminished. Sensory information such as haptics, which is essential for safe …

Integrated Analysis Of Hydrothermal Flow Through Pretreatment, Veronique Archambault-Leger, Xiongjun Shao, Lee R. Lynd

Dartmouth Scholarship

Background:

The impact of hydrothermal flowthrough (FT) pretreatment severity on pretreatment and solubilization performance metrics was evaluated for three milled feedstocks (corn stover, bagasse, and poplar) and two conversion systems (simultaneous saccharification and fermentation using yeast and fungal cellulase, and fermentation by Clostridium thermocellum).

Results:

Compared to batch pretreatment, FT pretreatment consistently resulted in higher XMG recovery, higher removal of non-carbohydrate carbon and higher glucan solubilization by simultaneous saccharification and fermentation (SSF). XMG recovery was above 90% for FT pretreatment below 4.1 severity but decreased at higher severities, particularly for bagasse. Removal of non-carbohydrate carbon during FT pretreatment increased …

Complex Geometries For Particle Image Velocimetry (Piv) Testing, Elaine T. Maestas, Ryan Wicker, David Espalin, Francisco R. Medina

COURI Symposium Abstracts, Summer 2012

Clear, physical models or phantoms are needed for particle image velocimetry (PIV) to accurately record fluid velocities within complex geometries including anatomical structures. Based on Karina Arcaute’s work on “Complex Silicon Cardiovascular Models Manufactured Using a Dip-Spin Coating Technique”, a box casting technique was developed to provide the most effective phantom for testing. The phantom is required to be free of visual obstructions, thus allowing a CCD camera to capture accurate velocity readings. In this study, complex parts were made of a water-soluble material and sanded until all ridges were removed. The model was created using a fused deposition modeling …

Characterization Of Printed Skin Equivalents, Mayela R, Aldaz Cervantes, Maria Yanez, Thomas Boland

COURI Symposium Abstracts, Summer 2012

Severe burns, ulcerations, and cuts are some of the reasons people need bioengineered skin as a treatment for full-thickness wounds. When patients run out of donor sites in their own body, using the patient’s skin as a graft is no longer an option, and tissue-engineered constructs are the only possible replacement for damaged skin. The goal of this research is to develop a hydrogel-based skin graft that will be able to function as a skin replacement in full-thickness wounds while minimizing the possibility of rejection, being cost-effective, and possessing a longer shelf-life than the grafts currently in the market. Endothelial …

Development Of A Vaccine Printer For Helicobacter Pylori, Gabriela Enriquez, Julio E. Rincon, Thomas Boland

COURI Symposium Abstracts, Summer 2012

Helicobacter pylori is present in approximately half of the world’s population, of which approximately 2% develop a type of gastric cancer. This cancer is often discovered when being in an advanced stage due to its lack of symptoms. Unfortunately, a vaccine hasn’t been successfully developed against the bacterium. Therefore, the aim of this research is to develop the functional prototype of a DNA vaccine printer. Its parts were designed in the program NX. 6.0 and built out of ABS plastic using printing technology at the University of Texas at El Paso. After being assembled, the printer will be programmed and …

Electrophoretic Screen And Functionalized Microspheres As Antigen Assays, Alejandra Hernandez, Julio Rincon, Thomas Boland

COURI Symposium Abstracts, Summer 2012

Immunoassays are used for medical diagnosis of infectious diseases. People in developing countries usually do not have access to this type of technologies, which makes infectious diseases the main cause of death in these countries. Immunoassay techniques assist the medical field with diagnosing, prognosis and monitoring of analytes present in the human body. This project will develop a portable antigen detection assay built using an electrophoretic screen with functionalized microspheres. A portable electrophoretic immunoassay will permit the reduction of lab materials and the independence of lab installations making it more accessible. This project involves two main steps: The screen modification …

Molecular Imprinting Of Silica Microspheres On Human Chorionic Gonadotropin, Paulina Almada, Julio E. Rincon, Thomas Boland

COURI Symposium Abstracts, Summer 2012

The technique of molecule imprinting prepares polymers with specific binding sites for a target molecule. Monomers are polymerized with a template present, arranging into a polymer matrix that can rebind the template once removed and creates the potential use of the polymers as artificial antibodies. The same process can be used to synthesize silica microspheres .The aim of this study was to test the ability of silica microspheres to bind human chorionic gonadotropin and be used as antibodies. 26.4 ml of tetraethoxysilane, 4.7 ml of water, 6.6 ml of 0.12 M hydrochloric acid, and 11.5 ml of 70% ethanol were …

Toward A Gpu-Accelerated Immersed Boundary Method For Wind Forecasting Over Complex Terrain, Rey Deleon, Kyle Felzien, Inanc Senocak

Mechanical and Biomedical Engineering Faculty Publications and Presentations

A short-term wind power forecasting capability can be a valuable tool in the renewable energy industry to address load-balancing issues that arise from intermittent wind fields. Although numerical weather prediction models have been used to forecast winds, their applicability to micro-scale atmospheric boundary layer flows and ability to predict wind speeds at turbine hub height with a desired accuracy is not clear. To address this issue, we develop a multi-GPU parallel flow solver to forecast winds over complex terrain at the micro-scale, where computational domain size can range from meters to several kilometers. In the solver, we adopt the immersed …

Weightlifting Performance Is Related To Kinematic And Kinetic Patterns Of The Hip And Knee Joints, Kristof Kipp, Josh Redden, Michelle B. Sabick, Chad Harris

Mechanical and Biomedical Engineering Faculty Publications and Presentations

The purpose of this study was to investigate correlations between biomechanical outcome measures and weightlifting performance. Joint kinematics and kinetics of the hip, knee, and ankle were calculated while ten subjects performed a clean at 85% of 1-RM. Kinematic and kinetic time-series patterns were extracted with principal components analysis. Discrete scores for each time-series pattern were calculated and used to determine how each pattern was related to body-mass normalized 1-RM. Two hip kinematic and two knee kinetic patterns were significantly correlated with relative 1-RM. The kinematic patterns captured hip and trunk motions during the first pull and hip joint motion …

Tissue Engineering A Blood Vessel Mimic While Monitoring Contamination Through Sterility Assurance Testing, Navid Djassemi

Master's Theses

Tissue Engineering A Blood Vessel Mimic While Monitoring Contamination Through Sterility Assurance Testing

Navid Djassemi

Tissue engineering blood vessel mimics has been proposed as a method to analyze the endothelial cell response to intravascular devices that are used in today’s clinical settings for the treatment of cardiovascular disease. Thus, the development of in vitro blood vessel mimics (BVMs) in Cal Poly’s Tissue Engineering Lab has introduced the possibility of assessing the characteristics of cellular response to past, present, and future intravascular devices that aim at treating coronary artery disease.

This thesis aimed at improving the methods and procedures utilized in …

Kinematic And Kinetic Synergies Of The Lower Extremities During The Pull In Olympic Weightlifting, Kristof Kipp, Josh Redden, Michelle Sabick, Chad Harris

Mechanical and Biomedical Engineering Faculty Publications and Presentations

The purpose of this study was to identify multijoint lower extremity kinematic and kinetic synergies in weightlifting and compare these synergies between joints and across different external loads. Subjects completed sets of the clean exercise at loads equal to 65, 75, and 85% of their estimated 1-RM. Functional data analysis was used to extract principal component functions (PCF's) for hip, knee, and ankle joint angles and moments of force during the pull phase of the clean at all loads. The PCF scores were then compared between joints and across loads to determine how much of each PCF was present at …

A Large-Scale Mathematical Model Of The Rat Pulmonary Circulation And The Effect Of Chronic Hypoxia, Loolu Rafeeq

Master's Theses (2009 -)

Mathematical models are useful for developing understanding of the behavior of complex biological systems. Recent work on a “physiome” project is aimed at using computational modeling to analyze integrative biological function by developing a simulation system for hypothesis testing (Borg & Hunter, 2003). To date, extensive work on cardiovascular, endocrine and nervous system models has been undertaken. Our objective here is to contribute to this effort by further developing a comprehensive integrative model of the pulmonary circulation. A computational model of the dog pulmonary circulation was originally developed by Haworth et al. (Haworth S. T., 1996; Haworth, Linehan, Bronikowski, & …

Noninvasive Optical Quantification Of Absolute Blood Flow, Blood Oxygenation, And Oxygen Consumption Rate In Exercising Skeletal Muscle, Katelyn Gurley, Yu Shang, Guoqiang Yu

Biomedical Engineering Faculty Publications

This study investigates a method using novel hybrid diffuse optical spectroscopies [near-infrared spectroscopy (NIRS) and diffuse correlation spectroscopy (DCS)] to obtain continuous, noninvasive measurement of absolute blood flow (BF), blood oxygenation, and oxygen consumption rate (V̇O₂) in exercising skeletal muscle. Healthy subjects (n=9) performed a handgrip exercise to increase BF and V̇O₂ in forearm flexor muscles, while a hybrid optical probe on the skin surface directly monitored oxy-, deoxy-, and total hemoglobin concentrations ([HbO₂], [Hb], and THC), tissue oxygen saturation (S_tO₂), relative BF (rBF), and relative oxygen …

Identification Of Proper And Common Names In The Anterior Temporal Lobe: An Fmri Study, Usha Tadimeti

Master's Theses (2009 -)

Temporal lobe epilepsy is a neurological disease that affects millions of individuals worldwide. They are usually treated through surgical resection of portions of the anterior temporal lobe (ATL). Surgical resection is effective for seizure control, but produces language and verbal memory deficits such as anomic aphasia, which adversely affects an individual's quality of life. The purpose of this study was to develop a functional MRI protocol for mapping the function of ATL in healthy subjects, and to better understand the role of the ATL and other regions of the semantic system. Such a protocol may ultimately be used by surgeons …