Biomedical Engineering and Bioengineering Commons^™

Mechanical Characterization Of Fourth Generation Composite Humerus, Prateek Grover, Carolyne Albert, Mei Wang, Gerald F. Harris

Biomedical Engineering Faculty Research and Publications

Mechanical data on upper extremity surrogate bones, supporting use as biomechanical tools, is limited. The objective of this study was to characterize the structural behaviour of the fourth-generation composite humerus under simulated physiologic bending, specifically, stiffness, rigidity, and mid-diaphysial surface strains. Three humeri were tested in four-point bending, in anatomically defined anteroposterior (AP) and mediolateral (ML) planes. Stiffness and rigidity were derived using load–displacement data. Principal strains were determined at the anterior, posterior, medial, and lateral surfaces in the humeral mid-diaphysial transverse plane of one specimen using stacked rosettes. Linear structural behaviour was observed within the test range. Average stiffness …

Quantifying The Tibiofemoral Joint Space Using X-Ray Tomosynthesis, Benjamin Kalinosky, John M. Sabol, Kelly Piacsek, Beth Heckel, Taly Gilat Schmidt

Biomedical Engineering Faculty Research and Publications

Purpose: Digital x-ray tomosynthesis (DTS) has the potential to provide 3D information about the knee joint in a load-bearing posture, which may improve diagnosis and monitoring of knee osteoarthritis compared with projection radiography, the current standard of care. Manually quantifying and visualizing the joint space width (JSW) from 3D tomosynthesis datasets may be challenging. This work developed a semiautomated algorithm for quantifying the 3D tibiofemoral JSW from reconstructed DTS images. The algorithm was validated through anthropomorphic phantom experiments and applied to three clinical datasets. Methods: A user-selected volume of interest within the reconstructed DTS volume was enhanced with 1D multiscale …

The Economics And Logistics Of The Dual Harvest Of Grain And Biomass In A Single-Pass, Matthew T. Wold

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

Significant interest has developed in using cellulosic resources, especially crop residues, to create biofuels. Collecting these residues in a single-pass of the harvester across the field has the potential to be a low cost option. Two models have been developed; the first characterizes the in-field logistics of single-pass crop residue collection, the second the economics. These models allow the user to easily examine a wide variety of both grain-only and single-pass residue collection harvest cases. A variety of possible residue collection cases have been examined, and their effects both on harvester field capacity and harvest cost compared to grain-only harvest …

Design And Fabrication Of Nanofluidic Systems For Biomolecule Characterizations, Orain Ansel Hibbert

Graduate Theses and Dissertations

Nanofluidic channel systems were designed and fabricated by combining MEMS microfabrication with AFM nanolithography. In the fabrication process flow, photolithography was first utilized to pattern microfluidic channels and reservoirs on a 4" Pyrex substrate. Subsequently, atomic force microscopy (AFM) based nanolithography was used to mechanically fabricate nanochannels to connect the microreservoirs which formed the inlet and outlet of the nanofluidic system. A Tap190 Diamond-Like Carbon (DLC) AFM tip with a force constant of 48 N/m and a radius of less than 15 nm was used as the nanolithography tool. The resultant nanochannel ranges from 20 to 80 µm in length …

Interfacial Force Field Parameterization Using The Dual Force Field Charmm Program For The Accurate Simulation Of Peptide-Surface Interaction, Nadeem Vellore

All Dissertations

Protein adsorption to solid material surfaces is a complex phenomenon and various factors play a role in controlling these processes. Inherent limitations to understand these biological interactions using experimental approaches alone have led to the possibility of exploring these systems using computational molecular simulation methodologies. Before confidence can be placed on these computational protocols, however, rigorous validation of the applicability of these methods to accurately represent protein adsorption processes is needed. In this research, we evaluated the use of all-atom empirical force field (FF) based simulations using the CHARMM simulation program and FF for the study of peptide adsorption processes …

Electrical Coupling Between Micropatterned Cardiomyocytes And Stem Cells, Zhen Ma

All Dissertations

To understand how stem cells functionally couple with native cardiomyocytes is crucial for cell-based therapies to restore the loss of cardiomyocytes that occurs during heart infarction and other cardiac diseases. Due to the complexity of the in vivo environment, our knowledge of cell coupling is heavily dependent on cell-culture models. However, conventional in vitro studies involve undefined cell shapes and random length of cell-cell contacts in addition to the presence of multiple homotypic and heterotypic contacts between interacting cells. Thus, it has not been feasible to study electrical coupling corresponding to isolated specific types of cell contact modes.
To address …

Development Of A Dynamic In Vitro Model Of A Stented Blood Vessel To Evaluate The Effects Of Stent Strut Material Selection And Surface Coating On Smooth Muscle Cell Response, Bradley Winn

All Dissertations

Cardiovascular disease is the leading cause of mortality in The United States and Europe, accounting for approximately half of all deaths. The most common form of cardiovascular disease is atherosclerosis, which is characterized by the formation of fatty atheromatous plaques that can grow to occlude the vessel lumen, thus causing ischemia distal to the occlusion. This is commonly treated using balloon angioplasty, which is usually done in conjunction with the deployment of a stent. Stent deployment helps hold the vessel open following the local injury caused by balloon inflation and prevents elastic recoil and subsequent negative remodeling. Stenting has been …

Designing Predictive Mathematical Models For The Metabolic Pathways Associated With Polyhydroxybutyrate Synthesis In Escherichia Coli, Angela Dixon

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Plastics are a versatile and widely used material. However, traditional plastics are derived from petrochemicals and are not biodegradable. Polymers synthesized from microorganisms that have similar properties to plastic are potential biodegradable replacements. The objective of this project is to use mathematical modeling as a tool to engineer a strain of bacteria optimized for the production of bio-plastics.

Production costs can be reduced by using a bacterial strain specifically optimized for bio-plastic production. By reducing production costs, bio-plastics will be able to commercially compete with traditional plastics. Society will benefit as bio-plastics replace traditional plastics. Fossil fuels will not be …

Directed Evolution Of Adeno-Associated Virus For Enhanced Gene Delivery And Gene Targeting In Human Pluripotent Stem Cells, Prashanth Asuri, Melissa Bartel, Tandis Vazin, Jae-Hyung Jang, Tiffany Wong, David Schaffer

Bioengineering

Efficient approaches for the precise genetic engineering of human pluripotent stem cells (hPSCs) can enhance both basic and applied stem cell research. Adenoassociated virus (AAV) vectors are of particular interest for their capacity to mediate efficient gene delivery to and gene targeting in various cells. However, natural AAV serotypes offer only modest transduction of human embryonic and induced pluripotent stem cells (hESCs and hiPSCs), which limits their utility for efficiently manipulating the hPSC genome. Directed evolution is a powerful means to generate viral vectors with novel capabilities, and we have applied this approach to create a novel AAV variant with …

Tissue Engineering An Acellular Bioresorbable Vascular Graft To Promote Regeneration, Patricia Wolfe

Theses and Dissertations

Tissue engineering is an interdisciplinary field that aims to restore, maintain, or improve diseased or damaged tissues. Electrospinning has become one of the most popular means to fabricate a scaffold for various tissue engineering applications as the process is extremely versatile and inexpensive. The ability for electrospinning to consistently create nanofibrous structures capable of mimicking the native extracellular matrix (ECM) is the basis behind why this technique is so successful in tissue engineering. Cardiovascular disease has been the leading cause of death in the United States for over 100 years, and because of this, the need for coronary artery replacements …

Differential Gene Expression To Investigate The Effects Of Low-Level Electrochemical Currents On Bacillus Subtilis., Robert Szkotak, Tagbo H R Niepa, Nikhil Jawrani, Jeremy L. Gilbert, Marcus B. Jones, Dacheng Ren

Biomedical and Chemical Engineering - All Scholarship

With the emergence and spread of multidrug resistant bacteria, effective methods to eliminate both planktonic bacteria and those embedded in surface-attached biofilms are needed. Electric currents at uA-mA/cm2 range are known to reduce the viability of bacteria. However, the mechanism of such effects is still not well understood. In this study, Bacillus subtilis was used as the model Gram-positive species to systematically investigate the effects of electrochemical currents on bacteria including the morphology, viability, and gene expression of planktonic cells, and viability of biofilm cells. The data suggest that weak electrochemical currents can effectively eliminate B. subtilis both as planktonic …

Migration And Invasion Of Brain Tumors, Richard A. Able, Jr., Veronica Dudu, Maribel Vazquez

Publications and Research

Recent advances in molecular biology have led to new insights in the development, growth and infiltrative behaviors of primary brain tumors (Demuth and Berens, 2004; Huse and Holland, 2010; Johnson et al., 2009; Kanu et al., 2009). These tumors are derived from various brain cell lineages and have been historically classified on the basis of morphological and, more recently, immunohistochemical features with less emphasis on their underlying molecular pathogenesis (Huse and Holland, 2010). The detailed molecular characterization of brain tumors has laid the groundwork for augmentation of standard treatment with patient-specific designed targeted therapies (Johnson et al., 2009; Kanu et …

Unstable Spinocerebellar Ataxia Type 10 (Attct) (Agaat) Repeats Are Associated With Aberrant Replication At The Atx10 Locus And Replication Origin-Dependent Expansion At An Ectopic Site In Human Cells, Guoqi Liu, John J. Bissler, Richard R. Sinden, Michael Leffak

Biomedical Engineering and Sciences Faculty Publications

Spinocerebellar ataxia type 10 (SCA10) is associated with expansion of (ATTCT)n repeats (where n is the number of repeats) within the ataxin 10 (ATX10/E46L) gene. The demonstration that (ATTCT)n tracts can act as DNA unwinding elements (DUEs) in vitro has suggested that aberrant replication origin activity occurs at expanded (ATTCT)n tracts and may lead to their instability. Here, we confirm these predictions. The wild-type ATX10 locus displays inefficient origin activity, but origin activity is elevated at the expanded ATX10 loci in patient-derived cells. To test whether (ATTCT)n tracts can potentiate origin activity, cell lines were constructed that contain ectopic copies …

Analysis Of 26" And 29" Wheel Mountain Bikes, Jacob Publicover, David Wang, Alex Warring

Mechanical Engineering

There are two major mountain bike diameter wheel sizes on the market today, but with two different options, one would naturally wonder, “Which one is best?” During the course of this project, 26 and 29 inch wheel mountain bikes were analyzed quantitatively and qualitatively, using a variety of test methods, from heart rate monitoring to serial data acquisition to computer simulated analyses; static, dynamic, theoretical, and subjective tests were administered.

Differential Il-21 Signaling In Apcs Leads To Disparate Th17 Differentiation In Diabetes-Susceptible Nod And Diabetes-Resistant Nod.Idd3 Mice., Sue M. Liu, David H. Lee, Jenna M. Sullivan, Denise Chung, Anneli Jäger, Bennett O V. Shum, Nora E. Sarvetnick, Ana C. Anderson, Vijay K. Kuchroo

Journal Articles: Regenerative Medicine

Type 1 diabetes (T1D) is an autoimmune disease that shows familial aggregation in humans and likely has genetic determinants. Disease linkage studies have revealed many susceptibility loci for T1D in mice and humans. The mouse T1D susceptibility locus insulin-dependent diabetes susceptibility 3 (Idd3), which has a homologous genetic interval in humans, encodes cytokine genes Il2 and Il21 and regulates diabetes and other autoimmune diseases; however, the cellular and molecular mechanisms of this regulation are still being elucidated. Here we show that T cells from NOD mice produce more Il21 and less Il2 and exhibit enhanced Th17 cell generation compared with …

Patterns Of Hypermetria And Terminal Cocontraction During Point-To-Point Movements Demonstrate Independent Action Of Trajectory And Postural Controllers, Robert A. Scheidt, Claude Ghez, Supriya Asnani

Biomedical Engineering Faculty Research and Publications

We examined elbow muscle activities and movement kinematics to determine how subjects combine elementary control actions in performing movements with one and two trajectory segments. In reaching, subjects made a rapid elbow flexion to a visual target before stabilizing the limb with either a low or a higher level of elbow flexor/extensor coactivity (CoA), which was cued by target diameter. Cursor diameter provided real-time biofeedback of actual muscle CoA. In reversing, the limb was to reverse direction within the target and return to the origin with minimal CoA. We previously reported that subjects overshoot the goal when attempting a reversal …

Effect Of Sensory Feedback From The Proximal Upper Limb On Voluntary Isometric Finger Flexion And Extension In Hemiparetic Stroke Subjects, Gilles Hoffmann, Brian D. Schmit, Jennifer H. Kahn, Derek G. Kamper

Biomedical Engineering Faculty Research and Publications

This study investigated the potential influence of proximal sensory feedback on voluntary distal motor activity in the paretic upper limb of hemiparetic stroke survivors and the potential effect of voluntary distal motor activity on proximal muscle activity. Ten stroke subjects and 10 neurologically intact control subjects performed maximum voluntary isometric flexion and extension, respectively, at the metacarpophalangeal (MCP) joints of the fingers in two static arm postures and under three conditions of electrical stimulation of the arm. The tasks were quantified in terms of maximum MCP torque [MCP flexion (MCP_flex) or MCP extension (MCP_ext)] and activity …

Sensing With The Motor Cortex, Nicholas G. Hatsopoulos, Aaron J. Suminski

Biomedical Engineering Faculty Research and Publications

The primary motor cortex is a critical node in the network of brain regions responsible for voluntary motor behavior. It has been less appreciated, however, that the motor cortex exhibits sensory responses in a variety of modalities including vision and somatosensation. We review current work that emphasizes the heterogeneity in sensorimotor responses in the motor cortex and focus on its implications for cortical control of movement as well as for brain-machine interface development.

Comparison Of Microwave And Conventionally Sintered Yttria-Doped Zirconia Ceramics, Colin J. Reidy, Thomas J. Fleming, Stuart Hampshire, Mark R. Towler

Chemical and Biochemical Engineering Faculty Research & Creative Works

This paper reports on improvement of the physical and mechanical properties of Y₂O₃-ZrO₂ ceramics through compositional optimization, the use of nanograined powders and utilization of microwave sintering. ZrO₂ with 2-5 mol% Y₂O₃, prepared from nanopowders, was sintered in both conventional and microwave furnaces under exactly the same heating schedule. It was found that microwave sintering improves physical and mechanical properties of Y₂O₃-ZrO₂ ceramics compared with conventional sintering. Compositions containing 2 mol% Y₂O₃ exhibit the greatest improvement due to retention of tetragonal ZrO …

Design, Fabrication, And Implementation Of A Wireless, Passive Implantable Pressure Sensor Based On Magnetic Higher-Order Harmonic Fields, Ee Lim Tan, Andrew Derouin, Brandon D. Pereles, Keat Ghee Ong

Michigan Tech Publications, Part 1

A passive and wireless sensor was developed for monitoring pressure in vivo. Structurally, the pressure sensor, referred to as the magneto-harmonic pressure sensor, is an airtight chamber sealed with an elastic pressure membrane. A strip of magnetically-soft material is attached to the bottom of the chamber and a permanent magnet strip is embedded inside the membrane. Under the excitation of an externally applied AC magnetic field, the magnetically-soft strip produces a higher-order magnetic signature that can be remotely detected with an external receiving coil. As ambient pressure varies, the pressure membrane deflects, altering the separation distance between the magnetically-soft strip …