Journal of Biomechanical Engineering 
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This is an RSS file. You can use it to subscribe to this data in your favourite RSS reader or to display this data on your own website or blog.Computationally Optimizing the Compliance of Multilayered Biomimetic Tissue Engineered Vascular Grafts
In this study, we have developed an experimental/computational approach to fabricate an acellular biomimetic hybrid tissue engineered vascular graft (TEVG) composed of alternating layers of electrospun porcine gelatin/polycaprolactone (PCL) and human tropoelastin/PCL blends with the goal of compliance-matching to rat abdominal aorta, while maintaining specific geometrical constraints. Polymeric blends at three different gelatin:PCL (G:PCL) and tropoelastin:PCL (T:PCL) ratios (80:20, 50:50, and 20:80) were mechanically characterized. The stress –strain data were used to develop predictive models, which were used as part o...
Source: Journal of Biomechanical Engineering - April 22, 2019 Category: Biomedical Engineering Source Type: research
Strain Mapping From Four-Dimensional Ultrasound Reveals Complex Remodeling in Dissecting Murine Abdominal Aortic Aneurysms
Current in vivo abdominal aortic aneurysm (AAA) imaging approaches tend to focus on maximum diameter but do not measure three-dimensional (3D) vascular deformation or strain. Complex vessel geometries, heterogeneous wall compositions, and surrounding structures can all influence aortic strain. Improved understanding of complex aortic kinematics has the potential to increase our ability to predict aneurysm expansion and eventual rupture. Here, we describe a method that combines four-dimensional (4D) ultrasound and direct deformation estimation to compute in vivo 3D Green-Lagrange strain in murine angiotensin II-induced supr...
Source: Journal of Biomechanical Engineering - April 22, 2019 Category: Biomedical Engineering Source Type: research
In Silico Performance of a Recellularized Tissue-Engineered Transcatheter Aortic Valve
In conclusion, we observed successful recellularization and remodeling of the tissue giving confidence to our TEHV material; however, the mechanical response indicates the additional remodeling would likely occur in the aortic/pulmonary position. (Source: Journal of Biomechanical Engineering)
Source: Journal of Biomechanical Engineering - April 22, 2019 Category: Biomedical Engineering Source Type: research
Numerical Investigation of Turbulence in Abdominal Aortic Aneurysms
Computational fluid dynamics (CFD) is a powerful method to investigate aneurysms. The primary focus of most investigations has been to compute various hemodynamic parameters to assess the risk posed by an aneurysm. Despite the occurrence of transitional flow in aneurysms, turbulence has not received much attention. In this article, we investigate turbulence in the context of abdominal aortic aneurysms (AAA). Since the clinical practice is to diagnose an AAA on the basis of its size, hypothetical axisymmetric geometries of various sizes are constructed. In general, just after the peak systole, a vortex ring is shed from the...
Source: Journal of Biomechanical Engineering - April 22, 2019 Category: Biomedical Engineering Source Type: research
The Effect of Oxidation on the Mechanical Response of Isolated Elastin and Aorta
Oxidation of aorta by hydroxyl radicals produces structural changes in arterial proteins like elastin and collagen. This in turn results in change in the mechanical response of aorta. In this paper, a thermodynamically consistent constitutive model is developed within the framework of mixture theory, to describe the changes in aorta and isolated elastin with oxidation. The model is then studied under uniaxial extension using experimental data from literature. (Source: Journal of Biomechanical Engineering)
Source: Journal of Biomechanical Engineering - April 22, 2019 Category: Biomedical Engineering Source Type: research
Computational Modeling and Analysis of Murmurs Generated by Modeled Aortic Stenoses
In this study, coupled hemodynamic –acoustic simulations are employed to study the generation and propagation of murmurs associated with aortic stenoses where the aorta with a stenosed aortic valve is modeled as a curved pipe with a constriction near the inlet. The hemodynamics of the poststenotic flow is investigated in detail in our previous numerical study (Zhu et al., 2018, “Computational Modelling and Analysis of Haemodynamics in a Simple Model of Aortic Stenosis,” J. Fluid Mech.,851, pp. 23 –49). The temporal history of the pressure on the aortic lumen is recorded during the hemodynamic study and used as the ...
Source: Journal of Biomechanical Engineering - March 5, 2019 Category: Biomedical Engineering Source Type: research
Mechanical Response of Human Muscle at Intermediate Strain Rates
We experimentally determined the tensile stress –strain response of human muscle along fiber direction and compressive stress–strain response transverse to fiber direction at intermediate strain rates (100–102/s). A hydraulically driven material testing system with a dynamic testing mode was used to perform the tensile and compressive experiments on human muscle tissue. Experiments at quasi-static strain rates (below 100/s) were also conducted to investigate the strain-rate effects over a wider range. The experimental results show that, at intermediate strain rates, both the human muscle's tensile and compressive str...
Source: Journal of Biomechanical Engineering - March 5, 2019 Category: Biomedical Engineering Source Type: research
Studies on the Stress-Strain Relationship Bovine Cortical Bone Based on Ramberg –Osgood Equation
Bone is a complex material that exhibits an amount of plasticity before bone fracture takes place, where the nonlinear relationship between stress and strain is of importance to understand the mechanism behind the fracture. This brief presents our study on the examination of the stress –strain relationship of bovine femoral cortical bone and the relationship representation by employing the Ramberg–Osgood (R–O) equation. Samples were taken and prepared from different locations (upper, middle, and lower) of bone diaphysis and were then subjected to the uniaxial tensile tests u nder longitudinal and transverse loading c...
Source: Journal of Biomechanical Engineering - March 5, 2019 Category: Biomedical Engineering Source Type: research
Model-Based Analysis of the Stiffness of the Wrist Joint in Active and Passive Conditions
The control of joint stiffness is a fundamental mechanism used to control human movements. While many studies have observed how stiffness is modulated for tasks involving shoulder and elbow motion, a limited amount of knowledge is available for wrist movements, though the wrist plays a crucial role in manipulation. We have developed a computational framework based on a realistic musculoskeletal model, which allows one to calculate the passive and active components of the wrist joint stiffness. We first used the framework to validate the musculoskeletal model against experimental measurements of the wrist joint stiffness, a...
Source: Journal of Biomechanical Engineering - February 27, 2019 Category: Biomedical Engineering Source Type: research
Accurate and Efficient Plate and Rod Microfinite Element Models for Whole Bone Segments Based on High-Resolution Peripheral Computed Tomography
In conclusion, the PR μFE model of HR-pQCT images accurately predicted mechanics for whole bone segments and can serve as a valuable clinical tool to evaluate musculoskeletal diseases. (Source: Journal of Biomechanical Engineering)
Source: Journal of Biomechanical Engineering - February 25, 2019 Category: Biomedical Engineering Source Type: research
Kinematic Accuracy in Tracking Total Wrist Arthroplasty With Biplane Videoradiography Using a Computed Tomography-Generated Model
Total wrist arthroplasty (TWA) for improving the functionality of severe wrist joint pathology has not had the same success, in parameters such as motion restoration and implant survival, as hip, knee, and shoulder arthroplasty. These other arthroplasties have been studied extensively, including the use of biplane videoradiography (BVR) that has allowed investigators to study the in vivo motion of the total joint replacement during dynamic activities. The wrist has not been a previous focus, and utilization of BVR for wrist arthroplasty presents unique challenges due to the design characteristics of TWAs. Accordingly, the ...
Source: Journal of Biomechanical Engineering - February 25, 2019 Category: Biomedical Engineering Source Type: research
Reduced Amount or Integrity of Arterial Elastic Fibers Alters Allometric Scaling Relationships for Aortic Diameter and Heart Weight, But Not Cardiac Function in Maturing Mice
Allometric scaling laws relate physiologic parameters to body weight. Genetically modified mice allow investigation of allometric scaling laws when fundamental cardiovascular components are altered. Elastin haploinsufficient (Eln+/ −) mice have reduced elastin amounts, and fibulin-5 knockout (Fbln5−/−) mice have compromised elastic fiber integrity in the large arteries which may alter cardiovascular scaling laws. Previously published echocardiography data used to investigate aortic and left ventricular function in Eln+/ − and Fbln5−/− mice throughout postnatal development and early adulthood were reanalyzed to ...
Source: Journal of Biomechanical Engineering - February 25, 2019 Category: Biomedical Engineering Source Type: research
Computational and Experimental Fatigue Analysis of Contoured Spinal Rods
Posterior fixation with contoured rods is an established methodology for the treatment of spinal deformities. Both uniform industrial preforming and intraoperative contouring introduce tensile and compressive plastic deformations, respectively, at the concave and at the convex sides of the rod. The purpose of this study is to develop a validated numerical framework capable of predicting how the fatigue behavior of contoured spinal rods is affected by residual stresses when loaded in lordotic and kyphotic configurations. Established finite element models (FEM) describing static contouring were implemented as a preliminary s...
Source: Journal of Biomechanical Engineering - February 25, 2019 Category: Biomedical Engineering Source Type: research
Quantification of Morphological Modulation, F-Actin Remodeling, and PECAM-1 (CD-31) Redistribution in Endothelial Cells in Response to Fluid-Induced Shear Stress Under Various Flow Conditions
Cardiovascular diseases (CVDs) are the number one cause of death globally. Arterial endothelial cell (EC) dysfunction plays a key role in many of these CVDs, such as atherosclerosis. Blood flow-induced wall shear stress (WSS), among many other pathophysiological factors, is known to significantly contribute to EC dysfunction. The present study reports an in vitro investigation of the effect of quantified WSS on ECs, analyzing the EC morphometric parameters and cytoskeletal remodeling. The effects of four different flow cases (low steady laminar (LSL), medium steady laminar (MSL), nonzero-mean sinusoidal laminar (NZMSL), an...
Source: Journal of Biomechanical Engineering - February 15, 2019 Category: Biomedical Engineering Source Type: research
Assessing Shoulder Biomechanics of Healthy Elderly Individuals During Activities of Daily Living Using Inertial Measurement Units: High Maximum Elevation Is Achievable but Rarely Used
This study demonstrates that individuals have the ability to achieve large ROMs but do not frequently do so. T hese results are consistent with the previously established lab-based measures. Moreover, they further inform how healthy individuals utilize their shoulders and may provide clinicians a reference for postsurgical ROM. (Source: Journal of Biomechanical Engineering)
Source: Journal of Biomechanical Engineering - February 13, 2019 Category: Biomedical Engineering Source Type: research
