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Journal of Biomechanical Engineering

Fatemeh Fatemifar, Marc Feldman, Meagan Oglesby, Hai-Chao Han
Trabeculae carneae account for a significant portion of human ventricular mass, despite being considered embryologic remnants. Recent studies have found trabeculae hypertrophy and fibrosis in hypertrophied left ventricles with various pathological conditions. The objective of this study was to investigate the passive mechanical properties and microstructural characteristics of trabeculae carneae and papillary muscles compared to the myocardium in human hearts. Uniaxial tensile tests were performed on samples of trabeculae carneae and myocardium strips, while biaxial tensile tests were performed on samples of papillary muscles and myocardium sheets...
November 10, 2018: Journal of Biomechanical Engineering
Ivan A Kuznetsov, Andrey Kuznetsov
Modeling of intracellular processes occurring during the development of Alzheimer's disease (AD) can be instrumental in understanding the disease and can potentially contribute to finding treatments for the disease. The model of intracellular processes in AD, which we previously developed, contains a large number of parameters. To distinguish between more important and less important parameters we performed a local sensitivity analysis of this model around the values of parameters that give the best fit with published experimental results...
November 1, 2018: Journal of Biomechanical Engineering
Derek/A Jones, James Gaewsky, Mona Saffarzadeh, Jacob Putnam, Ashley Weaver, Jeffrey Somers, Joel D Stitzel
The use of anthropomorphic test devices (ATDs) for calculating injury risk of occupants in spaceflight scenarios is crucial for ensuring the safety of crewmembers. Finite element (FE) modeling of ATDs reduces cost and time in the design process. The objective of this study was to validate a Hybrid III ATD FE model using a multi-direction test matrix for future spaceflight configurations. 25 Hybrid III physical tests were simulated using a 50th percentile male Hybrid III FE model. The sled acceleration pulses were approximately half-sine shaped, and can be described as a combination of peak acceleration and time to reach peak (rise time)...
November 1, 2018: Journal of Biomechanical Engineering
Vamsi Krishna Narla, Dharmendra Tripathi, O Anwar Beg
Embryological transport features a very interesting and complex application of peristaltic fluid dynamics. Electro- osmotic phenomena are also known to arise in embryo transfer location. The fluid dynamic environment in em- bryological systems is also known to be non-Newtonian and exhibits strong viscolastic properties. Motivated by these applications, the present article develops a new mathematical model for simulating two-dimensional peristaltic transport of a viscoelastic fluid in a tapered channel under the influence of electro-osmosis induced by asymmet- ric zeta potentials at the channel walls...
November 1, 2018: Journal of Biomechanical Engineering
Ashkan Javadzadegan
Computational fluid dynamics (CFD) modeling of myocardial bridging (MB) remains challenging due to its dynamic and phasic nature. This study aims to develop a patientspecific CFD model of MB. There were two parts to this study. The first part consisted of developing an in silico model of the left anterior descending (LAD) coronary artery of a patient with MB. In this regard, a moving-boundary CFD algorithm was developed to simulate the patient-specific muscle compression caused by MB. A second simulation was also performed with the bridge artificially removed to determine the hemodynamics in the same vessel in the absence of MB...
November 1, 2018: Journal of Biomechanical Engineering
Ishan Acharya, John Van Tuyl, Julia de Lange, Cheryl Quenneville
Lower leg injuries commonly occur in frontal automobile collisions, and are associated with high disability rates. Accurate methods to predict these injuries must be developed to facilitate the testing and improvement of vehicle safety systems. Anthropomorphic Test Devices (ATDs) are often used to assess injury risk by mimicking the behavior of the human body in a crash while recording data from sensors at discrete locations, which are then compared to established safety limits developed by cadaveric testing...
November 1, 2018: Journal of Biomechanical Engineering
Krista Durney, Danial Sharifi Kia, Tianbai Wang, Akaljot Singh, Lucie Karbowski, Hyeon Jin Koo, Gerard A Ateshian, Michael Albro
The ability to maintain living articular cartilage tissue in long-term culture can serve as a valuable analytical research tool, allowing for direct examination of mechanical or chemical perturbations on tissue behavior. A fundamental challenge for this technique is the recreation of the salient environmental conditions of the synovial joint in culture that are required to maintain native cartilage homeostasis. Interestingly, conventional media formulations used in explanted cartilage tissue culture investigations often consist of levels of metabolic mediators that deviate greatly from their concentrations in synovial fluid...
November 1, 2018: Journal of Biomechanical Engineering
Chris DiDomenico, Lawrence J Bonassar
Molecular transport of osteoarthritis (OA) therapeutics within articular cartilage is influenced by many factors, such as solute charge, that have yet to be fully understood. This study characterizes how solute charge influences local diffusion and convective transport of antibodies within the heterogeneous cartilage matrix. Three fluorescently-tagged solutes of varying isoelectric point (pI) (4.7-5.9) were tested in either cyclic or passive cartilage loading conditions. In each case, local diffusivities were calculated based on local fluorescence in the cartilage sample, as observed by confocal microscopy...
October 22, 2018: Journal of Biomechanical Engineering
Bo Qing, Elizabeth P Canovic, Aleksandar S Mijailovic, Anna Jagielska, Matthew J Whitfield, Alexis L Lowe, Elyza H Kelly, Daria Turner, Mustafa Sahin, Krystyn Van Vliet
Causes of Autism Spectrum Disorders (ASD) are understood poorly, making diagnosis and treatment challenging. While many studies have investigated the biochemical and genetic aspects of ASD, whether and how mechanical characteristics of the autistic brain can modulate neuronal connectivity and cognition in ASD are unknown. Previously, it has been shown that ASD brains are characterized by abnormal white matter and disorganized neuronal connectivity; we hypothesized that these significant cellular-level structural changes may translate to changes in the mechanical properties of the autistic brain or regions therein...
October 22, 2018: Journal of Biomechanical Engineering
Mirit Sharabi, Aviad Levi-Sasson, Roza Wolfson, Kelly R Wade, Fabio Galbusera, Dafna Benayahu, Hans-Joachim Wilke, Rami Haj-Ali
The annulus fibrosus (AF) of the intervertebral disc (IVD) consists of a set of concentric layers composed of a primary circumferential collagen fibers arranged in an alternating oblique orientation. Moreover, there exists an additional secondary set of radial translamellar collagen fibers which connects the concentric layers, creating an entangled fiber network. The aim of this study is to investigate the mechanical role of the radial fiber network. Towards that goal, a three-dimensional finite-element model of the L3-L4 spinal segment was generated, and calibrated to axial compression and pure moment loading...
October 22, 2018: Journal of Biomechanical Engineering
Khalil Alipour, Mahdy Eslamy
Human gait is the result of a complex and fascinating cooperation between different joints and segments in the lower extremity. This study aims at investigating the existence of this cooperation or the so-called synergy between the shank motion and the ankle motion. One potential use of this synergy is to develop the high level controllers for active foot prostheses/orthoses. The central point in this paper is to develop a high level controller that is able to continuously map shank kinematics (inputs) to ankle angles and torques (outputs)...
October 22, 2018: Journal of Biomechanical Engineering
William Barone, Katrina Knight, Pamela Moalli, Steven D Abramowitch
Synthetic mesh for pelvic organ prolapse repair is associated with high complication rates. While current devices incorporate large pores (>1 mm), recent studies have shown that uniaxial loading of mesh reduces pore size, raising the risk for complications. However, it's difficult to translate uniaxial results to transvaginal meshes, as in-vivo loading is multidirectional. Thus, the aim of this study was to 1) experimentally characterize deformation of pore diameters in a transvaginal mesh in response to clinically relevant multidirectional loading, and 2) develop a computational model to simulate mesh behavior in response to in-vivo loading conditions...
October 22, 2018: Journal of Biomechanical Engineering
Babak Safa, Michael H Santare, Dawn M Elliott
Fibrous tissues are biopolymeric materials that are made of extracellular proteins including several collagens and proteoglycans, and have a high water content. These tissues have non-linear, anisotropic, and inelastic mechanical behaviors that are often categorized into viscoelastic behavior, plastic deformation, and damage. While tissue's elastic and viscoelastic mechanical properties have been measured for decades, there is no comprehensive theoretical framework for modeling inelastic behaviors of these tissues that is based on their structure...
September 26, 2018: Journal of Biomechanical Engineering
David Molony, Jaekeun Park, Lei Zhou, Candace Fleischer, He-Ying Sun, Xiaoping Hu, John Oshinski, Habib Samady, Don P Giddens, Amir Rezvan
Animal models offer a flexible experimental environment for studying atherosclerosis. The mouse is the most commonly used animal, however, the underlying hemodynamics in larger animals such as the rabbit are far closer to that of humans. The aortic arch is a vessel with complex helical flow and highly heterogeneous shear stress patterns which may influence where atherosclerotic lesions form. A better understanding of intra-species flow variation and the impact of geometry on flow may improve our understanding of where disease forms...
August 21, 2018: Journal of Biomechanical Engineering
Aoife Healy, Kimberley Linyard-Tough, Nachiappan Chockalingam
While previous research has assessed the validity of the OptoGait system to the GAITRite walkway and an instrumented treadmill, no research to date has assessed this system against a traditional three-dimensional motion analysis system. Additionally, previous research has shown that the OptoGait system shows systematic bias when compared to other systems due to the configuration of the system's hardware. This study examined the agreement between the spatiotemporal gait parameters calculated from the OptoGait system and a three-dimensional motion capture (14 camera Vicon motion capture system and 2 AMTI force plates) in healthy adults...
January 1, 2019: Journal of Biomechanical Engineering
Eleuterio F Toro, Ben Thornber, Qinghui Zhang, Alessia Scoz, Christian Contarino
Global models for the dynamics of coupled fluid compartments of the central nervous system (CNS) require simplified representations of the individual components which are both accurate and computationally efficient. This paper presents a one-dimensional model for computing the flow of cerebrospinal fluid (CSF) within the spinal subarachnoid space (SSAS) under the simplifying assumption that it consists of two coaxial tubes representing the spinal cord and the dura. A rigorous analysis of the first-order nonlinear system demonstrates that the system is elliptic-hyperbolic, and hence ill-posed, for some values of parameters, being hyperbolic otherwise...
January 1, 2019: Journal of Biomechanical Engineering
John J Boyle, Arvin Soepriatna, Frederick Damen, Roger A Rowe, Robert B Pless, Attila Kovacs, Craig J Goergen, Stavros Thomopoulos, Guy M Genin
Quantifying dynamic strain fields from time-resolved volumetric medical imaging and microscopy stacks is a pressing need for radiology and mechanobiology. A critical limitation of all existing techniques is regularization: because these volumetric images are inherently noisy, the current strain mapping techniques must impose either displacement regularization and smoothing that sacrifices spatial resolution, or material property assumptions that presuppose a material model, as in hyperelastic warping. Here, we present, validate, and apply the first three-dimensional (3D) method for estimating mechanical strain directly from raw 3D image stacks without either regularization or assumptions about material behavior...
January 1, 2019: Journal of Biomechanical Engineering
K A Bonilla, A M Pardes, B R Freedman, L J Soslowsky
Sex differences in the mechanical properties of different musculoskeletal tissues and their impact on tendon function and disease are becoming increasingly recognized. Tendon mechanical properties are influenced by the presence or absence of sex hormones and these effects appear to be tendon- or ligament-specific. The objective of this study was to determine how sex and hormone differences in rats affect supraspinatus tendon and muscle properties. We hypothesized that male supraspinatus tendons would have increased cross-sectional area but no differences in tendon material properties or muscle composition when compared to supraspinatus tendons from female or ovariectomized (OVX) female rats...
January 1, 2019: Journal of Biomechanical Engineering
P C Raffalt, T Alkjær, B Brynjólfsson, L Jørgensen, C Bartholdy, M Henriksen
The present study investigated the day-to-day reliability (quantified by the absolute and relative reliability) of nonlinear methods used to assess human locomotion dynamics. Twenty-four participants of whom twelve were diagnosed with knee osteoarthritis completed 5 min of treadmill walking at self-selected preferred speed on two separate days. Lower limb kinematics were recorded at 100 Hz and hip, knee, and ankle joint angles, three-dimensional (3D) sacrum marker displacement and stride time intervals were extracted for 170 consecutive strides...
December 1, 2018: Journal of Biomechanical Engineering
A A Badachhape, R J Okamoto, R S Durham, D Efron, S J Nadell, C L Johnson, P V Bayly
No abstract text is available yet for this article.
December 1, 2018: Journal of Biomechanical Engineering
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