The Biomechanical Role Of Scaffolds In Augmented Rotator Cuff Tendon Repairs, 2012 Cleveland Clinic
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 …
Experimental Composite Guidance Conduits For Peripheral Nerve Repair: An Evaluation Of Ion Release, 2012 Missouri University of Science and technology
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+, …
Gallium Containing Glass Polyalkenoate Anti-Cancerous Bone Cements: Glass Characterization And Physical Properties, 2012 Missouri University of Science and Technology
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 (Tw) ranged from 68 to 96 s (Lcon.) and 106 s for the Ga-GPCs (LGa-1 and LGa-2). Setting times (Ts) …
The Effect Of A Navigational Aid On Training Of A Minimally Invasive Surgery Camera Task, 2012 Virginia Commonwealth University
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 …
Augmented Image-Guidance For Transcatheter Aortic Valve Implantation, 2012 The University of Western Ontario
Augmented Image-Guidance For Transcatheter Aortic Valve Implantation, Pencilla Lang
Electronic Thesis and Dissertation Repository
The introduction of transcatheter aortic valve implantation (TAVI), an innovative stent-based technique for delivery of a bioprosthetic valve, has resulted in a paradigm shift in treatment options for elderly patients with aortic stenosis. While there have been major advancements in valve design and access routes, TAVI still relies largely on single-plane fluoroscopy for intraoperative navigation and guidance, which provides only gross imaging of anatomical structures. Inadequate imaging leading to suboptimal valve positioning contributes to many of the early complications experienced by TAVI patients, including valve embolism, coronary ostia obstruction, paravalvular leak, heart block, and secondary nephrotoxicity from contrast use.
A …
Evaluation Of A Novel Myoelectric Training Device, 2012 Virginia Commonwealth University
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, …
Dynamics Of Depression Storage During Sprinkler Irrigation And Precipitation Events, 2012 University of Nebraska-Lincoln
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 (Ds) 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 …
Life History Switch Point Plasticy In Response To Pond Drying Alyers Metamorph Allometry And Jumping Performance, 2012 Virginia Commonwealth University
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 …
Bio-Inspired Design And Dynamic Maneuverability Of A Minimally Actuated Six-Legged Robot, 2012 Franklin W. Olin College of Engineering
Bio-Inspired Design And Dynamic Maneuverability Of A Minimally Actuated Six-Legged Robot, Aaron Hoover, Samuel Burden, Xiao-Yu Fu, S. Sastry, Ronald Fearing
Aaron M. Hoover
Rapidly running arthropods like cockroaches make use of passive dynamics to achieve remarkable locomotion performance with regard to stability, speed, and maneuverability. In this work, we take inspiration from these organisms to design, fabricate, and control a 10cm, 24 gram underactuated hexapedal robot capable of running at 14 body lengths per second and performing dynamic turning maneuvers. Our design relies on parallel kinematic mechanisms fabricated using the scaled smart composite microstructures (SCM) process and viscoelastic polymer legs with tunable stiffness. In addition to the novel robot design, we present experimental validation of the lateral leg spring (LLS) locomotion model's prediction …
Design, Analysis And Testing Of Haptic Feedback System For Laparoscopic Graspers In In Vivo Surgical Robots, 2012 University of Nebraska-Lincoln
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, 2012 Dartmouth College
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 …
Effect Of Applied Uniaxial Stress On Rate And Mechanical Effects Of Cross-Linking In Tissue-Derived Biomaterials, 2012 Franklin W. Olin College of Engineering
Effect Of Applied Uniaxial Stress On Rate And Mechanical Effects Of Cross-Linking In Tissue-Derived Biomaterials, Debbie Chachra, Paul Gratzer, Christopher Pereira, J. Lee
Debbie Chachra
Conformational changes in collagen fibrils, and indeed the triple helix, can be produced by application of mechanical stress or strain. We have demonstrated that the rate of cross-linking in glutaraldehyde and epoxide homobifunctional reagents can be modulated by uniaxial stress (strain). Two poly(glycidyl ether) epoxides were used: Denacol® EX-810 (a small bifunctional reagent), and Denacol EX-512 (a large polyfunctional reagent). To prevent any possible effect from being masked by saturation of cross-linking sites, bovine pericardium was cross-linked to such an extent that the increase in collagen denaturation temperature, Td, was one-half of the maximal rise achievable with …
Shelf-Life Of Bioprosthetic Heart Valves: A Structural And Mechanical Study, 2012 Universite Laval
Shelf-Life Of Bioprosthetic Heart Valves: A Structural And Mechanical Study, Maryse Julien, Dany Letouneau, Yves Marois, Alain Cardou, Martin King, Robert Guidoin, Debbie Chachra, J. Lee
Debbie Chachra
This study was undertaken to evaluate the influence of storage conditions on the shelf-life of porcine bioprosthetic valves. Fifty-five unimplanted porcine bioprostheses have been evaluated. The valves were stored in 0.5% buffered glutaraldehyde solution for different periods of time (7, 23 and 32 months). Twenty-eight valves were refrigerated while the remaining valves were stored at room temperature. The pH of the glutaraldehyde solution at room temperature decreased with time of storage, while that kept in the refrigerator remained stable over the course of the study. Macroscopic observations showed that the valve tissues kept at room temperature, especially for the periods …
Fluoride Treatment Increased Serum Igf-1, Bone Turnover, And Bone Mass, But Not Bone Strength, In Rabbits, 2012 Indiana University Schools of Medicine and Dentistry
Fluoride Treatment Increased Serum Igf-1, Bone Turnover, And Bone Mass, But Not Bone Strength, In Rabbits, C. Turner, L. Garetto, A. Dunipace, W. Zhang, M. Wilson, Marc Grynpas, Debbie Chachra, R. Mcclintock, M. Peacock, G. Stookey
Debbie Chachra
We hypothesized that fluoride partly acts by changing the levels of circulating calcium-regulating hormones and skeletal growth factors. The effects of oral fluoride on 24 female, Dutch-Belted, young adult rabbits were studied. The rabbits were divided into two study groups, one control and the other receiving about 16 mg fluoride/rabbit/day in their drinking water. After 6 months of fluoride dosing, all rabbits were euthanized and bone and blood samples were taken for analyses. Fluoride treatment increased serum and bone fluoride levels by over an order of magnitude (P < 0.001), but did not affect body weight or the following serum biochemical variables: urea, creatinine, phosphorus, total protein, albumin, bilirubin, SGOT, or total alkaline phosphatase. No skeletal fluorosis or osteomalacia was observed histologically, nor did fluoride affect serum PTH or Vitamin D metabolites (P > 0.4). BAP was increased 37% (P < 0.05) by fluoride; serum TRAP was increased 42% (P < 0.05); serum IGF-1 was increased 40% (P < 0.05). Fluoride increased the vertebral BV/TV by 35% (P …
The Effect Of Different Hormone Replacement Therapy Regimens On The Mechanical Properties Of Rat Vertebrae, 2012 Franklin W. Olin College of Engineering
The Effect Of Different Hormone Replacement Therapy Regimens On The Mechanical Properties Of Rat Vertebrae, Debbie Chachra, M. Kasra, Carla Vanin, N. Maclusky, R. Casper, Marc Grynpas
Debbie Chachra
The purpose of this study was to examine the effects of estrogen replacement, in concert with three different progestin regimens, on the mechanical properties of rat lumbar vertebrae. Ninety-two Sprague-Dawley rats (11 months old) were divided into six groups for treatment. The first group was an intact control, the second group (OVX) was ovariectomized only, and the third group (estrogen-only) was ovariectomized and received continuous estrogen through a 17-estradiol implant. The remaining groups were ovariectomized and received estrogen and progestin (norethindrone, NET) therapy; 3 g of NET was injected daily (estrogen plus continuous NET), or 6 g of NET was …
Toward A Gpu-Accelerated Immersed Boundary Method For Wind Forecasting Over Complex Terrain, 2012 Boise State University
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 …
The Effects Of Lubrication On Pharmaceutical Granules, 2012 The University of Western Ontario
The Effects Of Lubrication On Pharmaceutical Granules, Garett Morin
Electronic Thesis and Dissertation Repository
Spray-dried lactose was mixed with 4 different lubricants – magnesium stearate, magnesium silicate, stearic acid, and calcium stearate – in various concentrations. Flowability testing revealed that magnesium stearate improved powder flow until a threshold was reached, at which addition of lubricant had no effect. The addition of calcium stearate also improved flow; however, additional lubricant over the optimum amount further decreased flow. Full placebo granules were manufactured by both high shear and fluidized bed techniques. A granule comparison showed different growth mechanisms, surface morphology, particle size distribution, and flow characteristics for each manufacturing technique. The high shear granules demonstrated better …
Propagation Of Ultrasound Through Freshly Excised Human Calvarium, 2012 University of Nebraska – Lincoln
Propagation Of Ultrasound Through Freshly Excised Human Calvarium, Armando Garcia Noguera
Department of Engineering Mechanics: Dissertations, Theses, and Student Research
The propagation of ultrasound through complex biological media, such as the human calvarium, poses a great challenge for modern medicine. Several ultrasonic techniques commonly used for treatment and diagnosis in most of the human body are still difficult to apply to the human brain, in part, because of the properties of the skull. Moreover, an understanding of the biomechanics of transcranial ultrasound may provide needed insight into the problem of blast wave induced traumatic brain injury (TBI). In the present study, the spatial variability of ultrasonic properties was evaluated for relevant frequencies of 0.5, 1, and 2.25 MHz. A total …
Summer 2012 Biomedical Engineering Newsletter, 2012 Michigan Technological University
Summer 2012 Biomedical Engineering Newsletter, Department Of Biomedical Engineering, Michigan Technological University
Department of Biomedical Engineering Newsletters
Table of Contents
- Dr. Jeremy Goldman wins a Fulbright Scholarship
- Research updates
- Hal Holmes named Goldwater Scholar
- Top honors at the Undergraduate Expo
Examining Lower Extremity Motor Activity Using Magnetoencephalography, 2012 Marquette University
Examining Lower Extremity Motor Activity Using Magnetoencephalography, Ruth M. Swedler
Master's Theses (2009 -)
The role of the cortex during locomotion remains unclear, but recent advances in neural imaging technologies have aided in developing ways to measure brain activity during motor tasks. One method is by measuring activations produced by neural oscillations which have been associated with a variety of human behaviors, from sleep and rest to cognitive actions and movement. The physiological and functional methods in which oscillations contribute to cortical control are still largely unknown. In this study, we aim to expand that knowledge by examining human cortical activity in the sensory and motor cortices during pedaling using magnetoencephalography (MEG). We hypothesized …