Biomedical Engineering and Bioengineering Commons^™

Decoding And Reprogramming Fungal Iterative Nonribosomal Peptide Synthetases, Daya Yu, Fuchao Xu, Shuwei Zhang, Jixun Zhan

Biological Engineering Faculty Publications

Nonribosomal peptide synthetases (NRPSs) assemble a large group of structurally and functionally diverse natural products. While the iterative catalytic mechanism of bacterial NRPSs is known, it remains unclear how fungal NRPSs create products of desired length. Here we show that fungal iterative NRPSs adopt an alternate incorporation strategy. Beauvericin and bassianolide synthetases have the same C₁-A₁-T₁-C₂-A₂-MT-T_2a-T_2b-C₃ domain organization. During catalysis, C₃ and C₂ take turns to incorporate the two biosynthetic precursors into the growing depsipeptide chain that swings between T₁ and T …

Contributions Of Continuous Max-Flow Theory To Medical Image Processing, John Sh Baxter

Electronic Thesis and Dissertation Repository

Discrete graph cuts and continuous max-flow theory have created a paradigm shift in many areas of medical image processing. As previous methods limited themselves to analytically solvable optimization problems or guaranteed only local optimizability to increasingly complex and non-convex functionals, current methods based now rely on describing an optimization problem in a series of general yet simple functionals with a global, but non-analytic, solution algorithms. This has been increasingly spurred on by the availability of these general-purpose algorithms in an open-source context. Thus, graph-cuts and max-flow have changed every aspect of medical image processing from reconstruction to enhancement to segmentation …

A Deterministic Model Of The Effect Of Electric Field On Chemotherapeutics Delivery Into A Tumor, Maryam Moarefian, Luke Achenie

Biology and Medicine Through Mathematics Conference

No abstract provided.

The Impact Of The Mitochondrial Metabolism Of Induced Pluripotent Stem Cells Upon Differentiation, Stefanie T. Shahan

McKelvey School of Engineering Theses & Dissertations

Induced pluripotent stem cells (iPSCs) can be differentiated into any cell type found in the body. The derivation of a stem cell derived β cell (SC-β) capable of responding to glucose by secreting insulin was hugely significant for diabetes research and opened up the possibility of cell replacement therapy to combat this widespread disease (Pagliuca et al. 2014). The optimization of differentiation procedures such as this could improve yield, function, cost, and efficiency of a stem cell-derived product. Current approaches to improve differentiation are primarily focused on signal transduction pathways, while the metabolic state of the cells has received little …

Modeling Accommodation Control Of The Human Eye: Chromatic Aberration And Color Opponency, Agostino Gibaldi, Steven A. Cholewiak, Marty S. Banks

MODVIS Workshop

Accommodation is the process by which the eye lens changes optical power to maintain a clear retinal image as the distance to the fixated object varies. Although luminance blur has long been considered the driving feature for accommodation, it is by definition unsigned (i.e., there is no difference between the defocus of an object closer or farther than the focus distance). Nonetheless, the visual system initially accommodates in the correct direction, implying that it exploits a cue with sign information. Here, we present a model of accommodation control based on such a cue: Longitudinal Chromatic Aberration (LCA). The model relies …

A Tunable, Three-Dimensional In Vitro Culture Model Of Growth Plate Cartilage Using Alginate Hydrogel Scaffolds, Alek G. Erickson, Taylor D. Laughlin, Sarah Romereim, Catherine Sargus-Patino, Angela K. Pannier, Andrew T. Dudley

Biological Systems Engineering: Papers and Publications

Defining the final size and geometry of engineered tissues through precise control of the scalar and vector components of tissue growth is a necessary benchmark for regenerative medicine, but it has proved to be a significant challenge for tissue engineers. The growth plate cartilage that promotes elongation of the long bones is a good model system for studying morphogenetic mechanisms because cartilage is composed of a single cell type, the chondrocyte; chondrocytes are readily maintained in culture; and growth trajectory is predominately in a single vector. In this cartilage, growth is generated via a differentiation program that is spatially and …

Heuristics From Statistics—Modeling The Behavior And Perception Of Non-Rigid Materials, Vivian C. Paulun, Roland W. Fleming

MODVIS Workshop

No abstract provided.

Modelling Grip Point Selection In Human Precision Grip, Guido Maiello, Lina Klein, Vivian C. Paulun, Roland W. Fleming

MODVIS Workshop

No abstract provided.

Design And Validation Of Delivery Systems For Galectin-3 For Skin Healing Applications, Karrington A. Mcleod

Electronic Thesis and Dissertation Repository

Chronic wounds present a significant burden to patients, causing pain, impairing limb function, and often resulting in the need for amputation. Treatment of chronic dermal wounds is challenging, with current therapies showing limited efficacy in clinical trials. As galectin-3 has been implicated in several wound healing processes, its efficacy as a therapeutic in skin healing was investigated in this study. An electrospun gelatin scaffold loaded with galectin-3 was developed as a delivery system. The influence of human recombinant galectin-3 in skin healing, when delivered topically and using an electrospun scaffold, was then investigated in wild type and diabetic mice. Electrospun …

Pediatric Leukemia: Diagnosis To Treatment–A Review, Samantha C. Bernard, Ehab H. Abdelsamad, Paisley A. Johnson, Daniel L. Chapman, Madhukiran Parvathaneni

Faculty Works

Leukemia is cancer of the blood and bone marrow, it is the most common cancer found in children and is found to be more than one fourth of pediatric cancers. It causes white blood cells to become abnormal and the body to become weak. This deficiency in the immune system reduces the body's ability to fight infection or simple airborne illnesses, causing extensive treatment of common pathogens and cancer treatment. The present review covers all topics, from diagnosis to treatment of pediatric leukemia, as well as the stages of growth and physiological changes throughout the process. As leukemia has a …

Toward Measuring Network Aesthetics Based On Symmetry, Zengqiang Chen, Matthias Dehmer, Frank Emmert-Streib, Abbe Mowshowitz, Yongtang Shi

Publications and Research

In this exploratory paper, we discuss quantitative graph-theoretical measures of network aesthetics. Related work in this area has typically focused on geometrical features (e.g., line crossings or edge bendiness) of drawings or visual representations of graphs which purportedly affect an observer’s perception. Here we take a very different approach, abandoning reliance on geometrical properties, and apply information-theoretic measures to abstract graphs and networks directly (rather than to their visual representaions) as a means of capturing classical appreciation of structural symmetry. Examples are used solely to motivate the approach to measurement, and to elucidate our symmetry-based mathematical theory of network aesthetics.

Mri Applications In Tissue Engineering, Shadi Othman

Science Seminar Series

Shadi Othman of the School of Engineering and Computer Science Bioengineering Program, will speak on his research on MRI applications in tissue engineering.

Erratum To: Supplemental Vibrotactile Feedback Control Of Stabilization And Reaching Actions Of The Arm Using Limb State And Position Error Encodings, Alexis Krueger, Psiche Giannoni, Valay Shah, Maura Casadio, Robert A. Scheidt

Biomedical Engineering Faculty Research and Publications

The original article contained omissions mistakenly carried forward by the Production department handling this journal; these omissions related to missing ‘λ’ symbols throughout the article body, thus inaccurately representing the meaning of the associated text.

The article has now been updated to include these symbols in the appropriate sections of text to accurately reflect the conveyed implications.

Effects Of Bioengineering Scaffolds Releasing Neurotrophins And Body Weight Supported Treadmill Training On H-Reflex After Spinal Cord Injury, Jaclyn Ann Witko

Theses and Dissertations

Changes in monosynaptic reflex, often used to study spasticity, has been tested through the H-reflex in spinal cord injury (SCI) patients after rehabilitation training, such as body weight support treadmill training or cycling. The combinational effects of rehabilitation training and a bioengineered scaffold on spasticity in SCI animal model have not been studied. We used a clinically relevant animal model of spinal cord moderate contusion at T9/T10 with BWSTT and the bioengineered scaffold PNIPAAm-g-PEG loaded with the growth factors BDNF/NT-3 to measure the efficiency of the combinational bioengineered approach to treat spasticity. Five animal groups were included in the study: …

Supplemental Vibrotactile Feedback Control Of Stabilization And Reaching Actions Of The Arm Using Limb State And Position Error Encodings, Alexis Krueger, Psiche Giannoni, Valay Shah, Maura Casadio, Robert A. Scheidt

Biomedical Engineering Faculty Research and Publications

Deficits of kinesthesia (limb position and movement sensation) commonly limit sensorimotor function and its recovery after neuromotor injury. Sensory substitution technologies providing synthetic kinesthetic feedback might re-establish or enhance closed-loop control of goal-directed behaviors in people with impaired kinesthesia.

Dynamic Simulation And Analysis Of Gait Modification For Treating Knee Osteoarthritis, Taylor Elyse Schlotman

Doctoral Dissertations

Roughly 47.5 million people in the US have a disability, with 8.6 million reporting arthritis as their main cause of disability, making arthritis the leading cause of physical disability. With decreased mortality rates and a large, aging baby boomer generation, there will be more adults living with chronic musculoskeletal conditions causing disabilities that limit walking. Since walking ability is directly related to an individual’s independence at home and in the community, losing this ability is a major setback for patients with arthritis. Knee osteoarthritis (OA) is the most prevalent form of arthritis affecting approximately 27 million adults and accounts for …

Musculoskeletal Loads During Stationary Cycling And The Effects Of Pedal Modifications For Knee Osteoarthritis, Rachel Lynn Thompson

Doctoral Dissertations

Knee OA is a deteriorating joint disease affecting 27 million people in the US and current exercise prescriptions may be improved with new knowledge of their effects on muscle forces and joint contact loads. Cycling rather than other exercise modalities is generally considered an alternative for people with knee OA. If these research objectives were achieved, clinicians would have additional tools related to joint contact loads for treating people with OA with an cycling exercise while controlling progression of OA. The long-term goal of this research is to provide a scientific basis for planning, evaluation and improvement of subject-specific rehabilitation …

High-Throughput Functional System For Encapsulated Networks Of Model Cell Membranes, Mary-Anne Kim Anh Nguyen

Doctoral Dissertations

Synthetic lipid bilayers provide models of cell membranes to study biomolecular interactions and signal transduction. The droplet interface bilayer (DIB) is a highly versatile technique for assembling planar lipid membranes between water droplets in oil. The DIB method thus provides a unique capability for developing digital, droplet-based membrane platforms for rapid membrane characterization, drug screening and ion channel recordings. In this work, a new microfluidic system is presented that automates droplet generation, sorting, and sequential trapping in designated locations to enable rapid assembly of arrays of DIBs along with in situ electrical measurements. This platform provides repeatable processes for forming …

Development Of A Directional Bone Reaming System., Richard J Ackermann

Electronic Theses and Dissertations

Preparation of long bones such as the femur or tibia for placement of intramedullary devices for the treatment of fractures usually involves reaming with a series of central cutters driven by a drill-like device with a flexible shaft over a guide wire. The reamers sequentially enlarge the intramedullary canal into a tunnel of circular cross-section and a diameter appropriate for the procedure. The current technology is concentric, meaning that the system is self-centering within the original intramedullary canal and the expansion is symmetric with respect to the original centerline. A novel system for laterally deflecting the head of a 12mm …

Characterization And Manipulation Of Lipid Self-Assembly To Construct Stable, Portable Synthetic Lipid Bilayers, Guru Anand Venkatesan

Doctoral Dissertations

The overarching goal of this research work is to further our understanding of lipid self-assembly and its organization at an oil-water interface to support the development of synthetic lipid bilayer systems that can be used in biologically relevant fields such as membrane biophysics, protein electrophysiology, development of synthetic biomolecules, drugs, nanoparticles and other applications. Self-assembly kinetics and interfacial properties of lipid monolayers formed at a liquid-air and liquid-liquid interface are characterized using Langmuir-Blodgett trough and pendant drop tensiometer. Insights gained from these studies not only allow us to answer questions related to droplet interface bilayer (DIB; a promising technique to …