The Experts below are selected from a list of 2427 Experts worldwide ranked by ideXlab platform
John H. Bolte - One of the best experts on this subject based on the ideXlab platform.
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Dynamic properties of the upper thoracic spine-Pectoral Girdle (UTS-PG) system and corresponding kinematics in PMHS sled tests.
Stapp car crash journal, 2012Co-Authors: Jason Stammen, Rodney Herriott, Yun-seok Kang, Rebecca B. Dupaix, John H. BolteAbstract:Anthropomorphic test devices (ATDs) should accurately depict head kinematics in crash tests, and thoracic spine properties have been demonstrated to affect those kinematics. To investigate the relationships between thoracic spine system dynamics and upper thoracic kinematics in crash-level scenarios, three adult post-mortem human subjects (PMHS) were tested in both Isolated Segment Manipulation (ISM) and sled configurations. In frontal sled tests, the T6-T8 vertebrae of the PMHS were coupled through a novel fixation technique to a rigid seat to directly measure thoracic spine loading. Mid-thoracic spine and belt loads along with head, spine, and Pectoral Girdle (PG) displacements were measured in 12 sled tests conducted with the three PMHS (3-pt lap-shoulder belted/unbelted at velocities from 3.8 - 7.0 m/s applied directly through T6-T8). The sled pulse, ISM- derived characteristic properties of that PMHS, and externally applied forces due to head-neck inertia and shoulder belt constraint were used to predict kinematic time histories of the T1-T6 spine segment. The experimental impulse applied to the upper thorax was normalized to be consistent with a T6 force/sled acceleration sinusoidal profile, and the result was an improvement in the prediction of T3 X-axis displacements with ISM properties. Differences between experimental and model-predicted displacement-time history increases were quantified with respect to speed. These discrepancies were attributed to the lack of rotational inertia of the head-neck late in the event as well as restricted kyphosis and viscoelasticity of spine constitutive structures through costovertebral interactions and mid-spine fixation. The results indicate that system dynamic properties from sub-injurious ISM testing could be useful for characterizing forward trajectories of the upper thoracic spine in higher energy crash simulations, leading to improved biofidelity for both ATDs and finite element models.
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Sequential biomechanics of the human upper thoracic spine and Pectoral Girdle.
Annals of advances in automotive medicine. Association for the Advancement of Automotive Medicine. Annual Scientific Conference, 2012Co-Authors: Jason Stammen, Rodney Herriott, Yun-seok Kang, John H. Bolte, Rebecca B. DupaixAbstract:Thoracic spine flexibility affects head motion, which is critical to control in motor vehicle crashes given the frequency and severity of head injuries. The objective of this study is to investigate the dynamic response of the human upper thoracic region. An original experimental/analytical approach, Isolated Segment Manipulation (ISM), is introduced to quantify the intact upper thoracic spine-Pectoral Girdle (UTS-PG) dynamic response of six adult post-mortem human subjects (PMHS). A continuous series of small displacement, frontal perturbations were applied to the human UTS-PG using fifteen combinations of speed and constraint per PMHS. The non-parametric response of the T1-T6 lumped mass segment was obtained using a system identification technique. A parametric mass-damper-spring model was used to fit the non-parametric system response. Mechanical parameters of the upper thoracic spine were determined from the experimental model and analyzed in each speed/constraint configuration. The natural frequencies of the UTS-PG were 22.9 ± 7.1 rad/sec (shear, n=58), 32.1 ± 7.4 rad/sec (axial, n=58), and 27.8 ± 7.7 rad/sec (rotation, n=65). The damping ratios were 0.25 ± 0.20 (shear), 0.42 ± 0.24 (axial), and 0.58± 0.32 (rotation). N-way analysis of variance (Type III constrained sum of squares, no interaction effects) revealed that the relative effects of test speed, Pectoral Girdle constraint, and PMHS anthropometry on the UTS-PG dynamic properties varied per property and direction. While more work is needed to verify accuracy in realistic crash scenarios, the UTS-PG model system dynamic properties could eventually aid in developing integrated anthropomorphic test device (ATD) thoracic spine and shoulder components to provide improved head kinematics and belt interaction.
Jason Stammen - One of the best experts on this subject based on the ideXlab platform.
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Dynamic properties of the upper thoracic spine-Pectoral Girdle (UTS-PG) system and corresponding kinematics in PMHS sled tests.
Stapp car crash journal, 2012Co-Authors: Jason Stammen, Rodney Herriott, Yun-seok Kang, Rebecca B. Dupaix, John H. BolteAbstract:Anthropomorphic test devices (ATDs) should accurately depict head kinematics in crash tests, and thoracic spine properties have been demonstrated to affect those kinematics. To investigate the relationships between thoracic spine system dynamics and upper thoracic kinematics in crash-level scenarios, three adult post-mortem human subjects (PMHS) were tested in both Isolated Segment Manipulation (ISM) and sled configurations. In frontal sled tests, the T6-T8 vertebrae of the PMHS were coupled through a novel fixation technique to a rigid seat to directly measure thoracic spine loading. Mid-thoracic spine and belt loads along with head, spine, and Pectoral Girdle (PG) displacements were measured in 12 sled tests conducted with the three PMHS (3-pt lap-shoulder belted/unbelted at velocities from 3.8 - 7.0 m/s applied directly through T6-T8). The sled pulse, ISM- derived characteristic properties of that PMHS, and externally applied forces due to head-neck inertia and shoulder belt constraint were used to predict kinematic time histories of the T1-T6 spine segment. The experimental impulse applied to the upper thorax was normalized to be consistent with a T6 force/sled acceleration sinusoidal profile, and the result was an improvement in the prediction of T3 X-axis displacements with ISM properties. Differences between experimental and model-predicted displacement-time history increases were quantified with respect to speed. These discrepancies were attributed to the lack of rotational inertia of the head-neck late in the event as well as restricted kyphosis and viscoelasticity of spine constitutive structures through costovertebral interactions and mid-spine fixation. The results indicate that system dynamic properties from sub-injurious ISM testing could be useful for characterizing forward trajectories of the upper thoracic spine in higher energy crash simulations, leading to improved biofidelity for both ATDs and finite element models.
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Sequential biomechanics of the human upper thoracic spine and Pectoral Girdle.
Annals of advances in automotive medicine. Association for the Advancement of Automotive Medicine. Annual Scientific Conference, 2012Co-Authors: Jason Stammen, Rodney Herriott, Yun-seok Kang, John H. Bolte, Rebecca B. DupaixAbstract:Thoracic spine flexibility affects head motion, which is critical to control in motor vehicle crashes given the frequency and severity of head injuries. The objective of this study is to investigate the dynamic response of the human upper thoracic region. An original experimental/analytical approach, Isolated Segment Manipulation (ISM), is introduced to quantify the intact upper thoracic spine-Pectoral Girdle (UTS-PG) dynamic response of six adult post-mortem human subjects (PMHS). A continuous series of small displacement, frontal perturbations were applied to the human UTS-PG using fifteen combinations of speed and constraint per PMHS. The non-parametric response of the T1-T6 lumped mass segment was obtained using a system identification technique. A parametric mass-damper-spring model was used to fit the non-parametric system response. Mechanical parameters of the upper thoracic spine were determined from the experimental model and analyzed in each speed/constraint configuration. The natural frequencies of the UTS-PG were 22.9 ± 7.1 rad/sec (shear, n=58), 32.1 ± 7.4 rad/sec (axial, n=58), and 27.8 ± 7.7 rad/sec (rotation, n=65). The damping ratios were 0.25 ± 0.20 (shear), 0.42 ± 0.24 (axial), and 0.58± 0.32 (rotation). N-way analysis of variance (Type III constrained sum of squares, no interaction effects) revealed that the relative effects of test speed, Pectoral Girdle constraint, and PMHS anthropometry on the UTS-PG dynamic properties varied per property and direction. While more work is needed to verify accuracy in realistic crash scenarios, the UTS-PG model system dynamic properties could eventually aid in developing integrated anthropomorphic test device (ATD) thoracic spine and shoulder components to provide improved head kinematics and belt interaction.
Elizabeth L. Brainerd - One of the best experts on this subject based on the ideXlab platform.
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Pectoral and pelvic Girdle rotations during walking and swimming in a semi-aquatic turtle: testing functional role and constraint
The Journal of Experimental Biology, 2019Co-Authors: Christopher J. Mayerl, John G. Capano, Adam A. Moreno, Jeanette Wyneken, Richard W. Blob, Elizabeth L. BrainerdAbstract:ABSTRACT Pectoral and pelvic Girdle rotations play a substantial role in enhancing stride length across diverse tetrapod lineages. However, the Pectoral and pelvic Girdle attach the limbs to the body in different ways and may exhibit dissimilar functions, especially during locomotion in disparate environments. Here, we tested for functional differences between the forelimb and hindlimb of the freshwater turtle Pseudemys concinna during walking and swimming using X-ray reconstruction of moving morphology (XROMM). In doing so, we also tested the commonly held notion that the shell constrains Girdle motion in turtles. We found that the Pectoral Girdle exhibited greater rotations than the pelvic Girdle on land and in water. Additionally, pelvic Girdle rotations were greater on land than in water, whereas Pectoral Girdle rotations were similar in the two environments. These results indicate that although the magnitude of pelvic Girdle rotations depends primarily on whether the weight of the body must be supported against gravity, the magnitude of Pectoral Girdle rotations likely depends primarily on muscular activity associated with locomotion. Furthermore, the Pectoral Girdle of turtles rotated more than has been observed in other taxa with sprawling postures, showing an excursion similar to that of mammals (∼38 deg). These results suggest that a rigid axial skeleton and internally positioned Pectoral Girdle have not constrained turtle Girdle function, but rather the lack of lateral undulations in turtles and mammals may contribute to a functional convergence whereby the Girdle acts as an additional limb segment to increase stride length.
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Dual function of the Pectoral Girdle for feeding and locomotion in white-spotted bamboo sharks.
Proceedings. Biological sciences, 2017Co-Authors: Ariel L. Camp, Elizabeth L. Brainerd, Bradley Scott, Cheryl D. WilgaAbstract:Positioned at the intersection of the head, body and forelimb, the Pectoral Girdle has the potential to function in both feeding and locomotor behaviours—although the latter has been studied far mo...
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Supplementary table of mean peak chondrocranium kinematics (Table S1) and figures of XROMM methods (Fig. S1) and chondrocranium kinematics (Fig. S2) from Dual function of the Pectoral Girdle for feeding and locomotion in white-spotted bamboo sharks
2017Co-Authors: Ariel L. Camp, Elizabeth L. Brainerd, Bradley Scott, Cheryl D. WilgaAbstract:Supplementary Table 1: Mean (standard error) peak magnitudes of chondrocranium rotations (rot.) in degrees and translations (trans.) in millimeters. Figure S1. Filming methods and X-ray Reconstruction of Moving Morphology (XROMM). Biplanar x-ray videos were filmed obliquely during suction feeding (a). Sample X-ray image of cartilages and markers in one view (b). These images were combined with 3D polygonal models from CT scans (c) to reconstruct the motion of the chondrocranium, palatoquadrate (teal), Meckel's cartilage (blue), ceratohyal (orange), and Pectoral Girdle. A body plane was calculated from the motion of 3-6 intramuscular markers (red). Figure S2. Kinematics of the chondrocranium, measured relative to the body plane. A joint coordinate system (A) measured motion as rotations (B) and translations (C) about each axis (data in these panels are from a sample strike). (D) Z-axis rotations (i.e., elevation and depression) of the chondrocranium from each strike (blue lines), as well as the mean rotation at each time step (black line), for each individual. Time is calculated relative to the time of peak gape
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Supplementary movie of Pectoral Girdle motion (Movie S1) from Dual function of the Pectoral Girdle for feeding and locomotion in white-spotted bamboo sharks
2017Co-Authors: Ariel L. Camp, Elizabeth L. Brainerd, Bradley Scott, Cheryl D. WilgaAbstract:XROMM animation of a sample bamboo shark (Bam04) suction feeding strike, viewed relative to the body plane. The motion of the Pectoral Girdle (blue cartilage model) is shown along with its initial position (white cartilage model) for reference
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Movie S1 from Dual function of the Pectoral Girdle for feeding and locomotion in white-spotted bamboo sharks
2017Co-Authors: Ariel L. Camp, Elizabeth L. Brainerd, Bradley Scott, Cheryl D. WilgaAbstract:XROMM animation of a sample bamboo shark (Bam04) suction feeding strike, viewed relative to the body plane. The motion of the Pectoral Girdle (blue cartilage model) is shown along with its initial position (white cartilage model) for reference
Rebecca B. Dupaix - One of the best experts on this subject based on the ideXlab platform.
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Dynamic properties of the upper thoracic spine-Pectoral Girdle (UTS-PG) system and corresponding kinematics in PMHS sled tests.
Stapp car crash journal, 2012Co-Authors: Jason Stammen, Rodney Herriott, Yun-seok Kang, Rebecca B. Dupaix, John H. BolteAbstract:Anthropomorphic test devices (ATDs) should accurately depict head kinematics in crash tests, and thoracic spine properties have been demonstrated to affect those kinematics. To investigate the relationships between thoracic spine system dynamics and upper thoracic kinematics in crash-level scenarios, three adult post-mortem human subjects (PMHS) were tested in both Isolated Segment Manipulation (ISM) and sled configurations. In frontal sled tests, the T6-T8 vertebrae of the PMHS were coupled through a novel fixation technique to a rigid seat to directly measure thoracic spine loading. Mid-thoracic spine and belt loads along with head, spine, and Pectoral Girdle (PG) displacements were measured in 12 sled tests conducted with the three PMHS (3-pt lap-shoulder belted/unbelted at velocities from 3.8 - 7.0 m/s applied directly through T6-T8). The sled pulse, ISM- derived characteristic properties of that PMHS, and externally applied forces due to head-neck inertia and shoulder belt constraint were used to predict kinematic time histories of the T1-T6 spine segment. The experimental impulse applied to the upper thorax was normalized to be consistent with a T6 force/sled acceleration sinusoidal profile, and the result was an improvement in the prediction of T3 X-axis displacements with ISM properties. Differences between experimental and model-predicted displacement-time history increases were quantified with respect to speed. These discrepancies were attributed to the lack of rotational inertia of the head-neck late in the event as well as restricted kyphosis and viscoelasticity of spine constitutive structures through costovertebral interactions and mid-spine fixation. The results indicate that system dynamic properties from sub-injurious ISM testing could be useful for characterizing forward trajectories of the upper thoracic spine in higher energy crash simulations, leading to improved biofidelity for both ATDs and finite element models.
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Sequential biomechanics of the human upper thoracic spine and Pectoral Girdle.
Annals of advances in automotive medicine. Association for the Advancement of Automotive Medicine. Annual Scientific Conference, 2012Co-Authors: Jason Stammen, Rodney Herriott, Yun-seok Kang, John H. Bolte, Rebecca B. DupaixAbstract:Thoracic spine flexibility affects head motion, which is critical to control in motor vehicle crashes given the frequency and severity of head injuries. The objective of this study is to investigate the dynamic response of the human upper thoracic region. An original experimental/analytical approach, Isolated Segment Manipulation (ISM), is introduced to quantify the intact upper thoracic spine-Pectoral Girdle (UTS-PG) dynamic response of six adult post-mortem human subjects (PMHS). A continuous series of small displacement, frontal perturbations were applied to the human UTS-PG using fifteen combinations of speed and constraint per PMHS. The non-parametric response of the T1-T6 lumped mass segment was obtained using a system identification technique. A parametric mass-damper-spring model was used to fit the non-parametric system response. Mechanical parameters of the upper thoracic spine were determined from the experimental model and analyzed in each speed/constraint configuration. The natural frequencies of the UTS-PG were 22.9 ± 7.1 rad/sec (shear, n=58), 32.1 ± 7.4 rad/sec (axial, n=58), and 27.8 ± 7.7 rad/sec (rotation, n=65). The damping ratios were 0.25 ± 0.20 (shear), 0.42 ± 0.24 (axial), and 0.58± 0.32 (rotation). N-way analysis of variance (Type III constrained sum of squares, no interaction effects) revealed that the relative effects of test speed, Pectoral Girdle constraint, and PMHS anthropometry on the UTS-PG dynamic properties varied per property and direction. While more work is needed to verify accuracy in realistic crash scenarios, the UTS-PG model system dynamic properties could eventually aid in developing integrated anthropomorphic test device (ATD) thoracic spine and shoulder components to provide improved head kinematics and belt interaction.
Yun-seok Kang - One of the best experts on this subject based on the ideXlab platform.
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Dynamic properties of the upper thoracic spine-Pectoral Girdle (UTS-PG) system and corresponding kinematics in PMHS sled tests.
Stapp car crash journal, 2012Co-Authors: Jason Stammen, Rodney Herriott, Yun-seok Kang, Rebecca B. Dupaix, John H. BolteAbstract:Anthropomorphic test devices (ATDs) should accurately depict head kinematics in crash tests, and thoracic spine properties have been demonstrated to affect those kinematics. To investigate the relationships between thoracic spine system dynamics and upper thoracic kinematics in crash-level scenarios, three adult post-mortem human subjects (PMHS) were tested in both Isolated Segment Manipulation (ISM) and sled configurations. In frontal sled tests, the T6-T8 vertebrae of the PMHS were coupled through a novel fixation technique to a rigid seat to directly measure thoracic spine loading. Mid-thoracic spine and belt loads along with head, spine, and Pectoral Girdle (PG) displacements were measured in 12 sled tests conducted with the three PMHS (3-pt lap-shoulder belted/unbelted at velocities from 3.8 - 7.0 m/s applied directly through T6-T8). The sled pulse, ISM- derived characteristic properties of that PMHS, and externally applied forces due to head-neck inertia and shoulder belt constraint were used to predict kinematic time histories of the T1-T6 spine segment. The experimental impulse applied to the upper thorax was normalized to be consistent with a T6 force/sled acceleration sinusoidal profile, and the result was an improvement in the prediction of T3 X-axis displacements with ISM properties. Differences between experimental and model-predicted displacement-time history increases were quantified with respect to speed. These discrepancies were attributed to the lack of rotational inertia of the head-neck late in the event as well as restricted kyphosis and viscoelasticity of spine constitutive structures through costovertebral interactions and mid-spine fixation. The results indicate that system dynamic properties from sub-injurious ISM testing could be useful for characterizing forward trajectories of the upper thoracic spine in higher energy crash simulations, leading to improved biofidelity for both ATDs and finite element models.
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Sequential biomechanics of the human upper thoracic spine and Pectoral Girdle.
Annals of advances in automotive medicine. Association for the Advancement of Automotive Medicine. Annual Scientific Conference, 2012Co-Authors: Jason Stammen, Rodney Herriott, Yun-seok Kang, John H. Bolte, Rebecca B. DupaixAbstract:Thoracic spine flexibility affects head motion, which is critical to control in motor vehicle crashes given the frequency and severity of head injuries. The objective of this study is to investigate the dynamic response of the human upper thoracic region. An original experimental/analytical approach, Isolated Segment Manipulation (ISM), is introduced to quantify the intact upper thoracic spine-Pectoral Girdle (UTS-PG) dynamic response of six adult post-mortem human subjects (PMHS). A continuous series of small displacement, frontal perturbations were applied to the human UTS-PG using fifteen combinations of speed and constraint per PMHS. The non-parametric response of the T1-T6 lumped mass segment was obtained using a system identification technique. A parametric mass-damper-spring model was used to fit the non-parametric system response. Mechanical parameters of the upper thoracic spine were determined from the experimental model and analyzed in each speed/constraint configuration. The natural frequencies of the UTS-PG were 22.9 ± 7.1 rad/sec (shear, n=58), 32.1 ± 7.4 rad/sec (axial, n=58), and 27.8 ± 7.7 rad/sec (rotation, n=65). The damping ratios were 0.25 ± 0.20 (shear), 0.42 ± 0.24 (axial), and 0.58± 0.32 (rotation). N-way analysis of variance (Type III constrained sum of squares, no interaction effects) revealed that the relative effects of test speed, Pectoral Girdle constraint, and PMHS anthropometry on the UTS-PG dynamic properties varied per property and direction. While more work is needed to verify accuracy in realistic crash scenarios, the UTS-PG model system dynamic properties could eventually aid in developing integrated anthropomorphic test device (ATD) thoracic spine and shoulder components to provide improved head kinematics and belt interaction.
