scholarly journals Integration of biplanar X-ray, three-dimensional animation and particle simulation reveals details of human ‘track ontogeny’

2021 ◽  
Vol 11 (5) ◽  
pp. 20200075
Author(s):  
Kevin G. Hatala ◽  
Stephen M. Gatesy ◽  
Peter L. Falkingham
Keyword(s):  
Three Dimensional ◽  
Particle Simulation ◽  
Foot Kinematics ◽  
X Ray ◽  
Human Fossil ◽  
Track Formation ◽  
Robust Hypothesis Testing ◽  
Locomotor Patterns ◽  
Fossil Hominin

The emergence of bipedalism had profound effects on human evolutionary history, but the evolution of locomotor patterns within the hominin clade remains poorly understood. Fossil tracks record in vivo behaviours of extinct hominins, and they offer great potential to reveal locomotor patterns at various times and places across the human fossil record. However, there is no consensus on how to interpret anatomical or biomechanical patterns from tracks due to limited knowledge of the complex foot–substrate interactions through which they are produced. Here, we implement engineering-based methods to understand human track formation with the ultimate goal of unlocking invaluable information on hominin locomotion from fossil tracks. We first developed biplanar X-ray and three-dimensional animation techniques that permit visualization of subsurface foot motion as tracks are produced, and that allow for direct comparisons of foot kinematics to final track morphology. We then applied the discrete element method to accurately simulate the process of human track formation, allowing for direct study of human track ontogeny. This window lets us observe how specific anatomical and/or kinematic variables shape human track morphology, and it offers a new avenue for robust hypothesis testing in order to infer patterns of foot anatomy and motion from fossil hominin tracks.

Kinematics of the Ankle/Foot Complex: Plantarflexion and Dorsiflexion

Foot & Ankle ◽  
1989 ◽  
Vol 9 (4) ◽  
pp. 194-200 ◽  
Author(s):  
Arne Lundberg ◽  
Ian Goldie ◽  
Bo Kalin ◽  
Göran Selvik
Keyword(s):  
Plantar Flexion ◽  
Three Dimensional ◽  
Substantial Contribution ◽  
Neutral Position ◽  
Transverse Axis ◽  
Talocrural Joint ◽  
Foot Kinematics ◽  
Talocalcaneal Joint ◽  
Axis Rotation

In an in vivo investigation of eight healthy volunteers, three dimensional ankle/foot kinematics were analyzed by roentgen stereophotogrammetry in 10° steps of motion from 30° of plantar flexion to 30° of dorsiflexion of the foot. The study included all of the joints between the tibia and the first metatarsal, as well as the talocalcaneal joint, and was performed under full body load. Although the talocrural joint was found to account for most of the rotation around the transverse axis occurring from 30° of plantar flexion to 30° of dorsiflexion, there was a substantial contribution from the joints of the arch. This was seen particularly in the input arc from 30° of plantar flexion to the neutral position, where the dorsiflexion motion of these joints amounted to 10% to 41% of the total transverse axis rotation.

Three-Dimensional Characterization of the Microstructure of Bioglass/Polyethylene Composite by X-Ray Microtomography

2007 ◽  
Vol 330-332 ◽  
pp. 503-506
Author(s):  
Xiao Wei Fu ◽  
Jie Huang ◽  
E.S. Thian ◽  
Serena Best ◽  
William Bonfield
Keyword(s):  
Spatial Distribution ◽  
Volume Fraction ◽  
Three Dimensional ◽  
X Ray ◽  
Polyethylene Composite ◽  
Bioactive Properties ◽  
Recent Developments ◽  
3D Information

A Bioglass® reinforced polyethylene (Bioglass®/polyethylene) composite has been prepared, which combines the high bioactivity of Bioglass® and the toughness of polyethylene. The spatial distribution of Bioglass® particles within the composite is important for the performance of composites in-vivo. Recent developments in X-ray microtomography (XμT) have made it possible to visualize internal and microstructural details with different X-ray absorbencies, nondestructively, and to acquire 3D information at high spatial resolution. In this study, the volume fraction and 3D spatial distribution of Bioglass® particles has been acquired quantitatively by XμT. The information obtained provides a foundation for understanding the mechanical and bioactive properties of the Bioglass®/polyethylene composites.

In vivo noninvasive three‐dimensional (3D) assessment of microwave thermal ablation zone using non‐contrast‐enhanced x‐ray CT

2020 ◽  
Vol 47 (10) ◽  
pp. 4721-4734
Author(s):  
Omri Ziv ◽  
S. Nahum Goldberg ◽  
Yitzhak Nissenbaum ◽  
Jacob Sosna ◽  
Noam Weiss ◽  
...  
Keyword(s):  
Thermal Ablation ◽  
Three Dimensional ◽  
Ablation Zone ◽  
X Ray ◽  
Contrast Enhanced

scholarly journals In vivo intraoral waterflow quantification reveals hidden mechanisms of suction feeding in fish

2021 ◽  
Author(s):  
Pauline Provini ◽  
Alexandre Brunet ◽  
Andréa Filippo ◽  
Sam Van Wassenbergh
Keyword(s):  
High Speed ◽  
Three Dimensional ◽  
New Technique ◽  
Fish Feed ◽  
Suction Feeding ◽  
Apparent Paradox ◽  
X Ray ◽  
Water Flows ◽  
Food Transport

Virtually all fish rely on flows of water to transport food to the back of their pharynx. While external flows that draw food into the mouth are well described, how intra-oral water flows manage to deposit food at the esophagus entrance remains unknown. In theory, the posteriorly moving water must, at some point, curve laterally and/or ventrally to exit through the gill slits. Such flows would eventually carry food away from the esophagus instead of towards it. This apparent paradox calls for a filtration mechanism to deviate food from the suction-feeding streamlines. To study this gap in our fundamental understanding of how fish feed, we developed and applied a new technique to quantify three-dimensional patterns of intra-oral water flows in vivo. We combined stereoscopic high-speed x-ray videos to quantify skeletal motion (XROMM) with 3D x-ray particle tracking (XPT) of approximately neutrally buoyant spheres of 1.4 mm in diameter. We showed, for carp (Cyprinus carpio) and tilapia (Oreochromis niloticus), that water tracers displayed higher curvatures than food tracers, indicating an inertia-driven filtration. In addition, tilapia also exhibited a 'central jet' flow pattern, which aids in quickly carrying food to the pharyngeal jaw region. When the food was trapped at the branchial basket, it was resuspended and carried more centrally by periodical bidirectional waterflows, synchronized with head-bone motions. By providing a complete picture of the suction-feeding process and revealing fundamental differences in food transport mechanisms among species, this new technique opens a new area of investigation to fully understand how most aquatic vertebrates feed.

scholarly journals A neck-like vertebral motion in fish

2021 ◽  
Vol 288 (1957) ◽  
pp. 20211091
Author(s):  
Ariel L. Camp
Keyword(s):  
Rainbow Trout ◽  
Oncorhynchus Mykiss ◽  
Vertebral Column ◽  
Three Dimensional ◽  
The Body ◽  
X Ray ◽  
Control Motion ◽  
Caudal Vertebrae ◽  
Vertebral Kinematics

Tetrapods use their neck to move the head three-dimensionally, relative to the body and limbs. Fish lack this anatomical neck, yet during feeding many species elevate (dorsally rotate) the head relative to the body. Cranial elevation is hypothesized to result from the craniovertebral and cranial-most intervertebral joints acting as a neck, by dorsally rotating (extending). However, this has never been tested due to the difficulty of visualizing and measuring vertebral motion in vivo . I used X-ray reconstruction of moving morphology to measure three-dimensional vertebral kinematics in rainbow trout ( Oncorhynchus mykiss ) and Commerson's frogfish ( Antennarius commerson ) during feeding. Despite dramatically different morphologies, in both species dorsoventral rotations extended far beyond the craniovertebral and cranial intervertebral joints. Trout combine small (most less than 3°) dorsal rotations over up to a third of their intervertebral joints to elevate the neurocranium. Frogfish use extremely large (often 20–30°) rotations of the craniovertebral and first intervertebral joint, but smaller rotations occurred across two-thirds of the vertebral column during cranial elevation. Unlike tetrapods, fish rotate large regions of the vertebral column to rotate the head. This suggests both cranial and more caudal vertebrae should be considered to understand how non-tetrapods control motion at the head–body interface.

Capturing Three-Dimensional In Vivo Lumbar Intervertebral Joint Kinematics Using Dynamic Stereo-X-Ray Imaging

2013 ◽  
Vol 136 (1) ◽  
Author(s):  
Ameet K. Aiyangar ◽  
Liying Zheng ◽  
Scott Tashman ◽  
William J. Anderst ◽  
Xudong Zhang
Keyword(s):  
Lumbar Spine ◽  
Three Dimensional ◽  
Lumbar Vertebrae ◽  
Lumbar Vertebra ◽  
Weight Lifting ◽  
Data Set ◽  
X Ray ◽  
Biomechanical Models ◽  
Lifting Task

Availability of accurate three-dimensional (3D) kinematics of lumbar vertebrae is necessary to understand normal and pathological biomechanics of the lumbar spine. Due to the technical challenges of imaging the lumbar spine motion in vivo, it has been difficult to obtain comprehensive, 3D lumbar kinematics during dynamic functional tasks. The present study demonstrates a recently developed technique to acquire true 3D lumbar vertebral kinematics, in vivo, during a functional load-lifting task. The technique uses a high-speed dynamic stereo-radiography (DSX) system coupled with a volumetric model-based bone tracking procedure. Eight asymptomatic male participants performed weight-lifting tasks, while dynamic X-ray images of their lumbar spines were acquired at 30 fps. A custom-designed radiation attenuator reduced the radiation white-out effect and enhanced the image quality. High resolution CT scans of participants' lumbar spines were obtained to create 3D bone models, which were used to track the X-ray images via a volumetric bone tracking procedure. Continuous 3D intervertebral kinematics from the second lumbar vertebra (L2) to the sacrum (S1) were derived. Results revealed motions occurring simultaneously in all the segments. Differences in contributions to overall lumbar motion from individual segments, particularly L2–L3, L3–L4, and L4–L5, were not statistically significant. However, a reduced contribution from the L5–S1 segment was observed. Segmental extension was nominally linear in the middle range (20%–80%) of motion during the lifting task, but exhibited nonlinear behavior at the beginning and end of the motion. L5–S1 extension exhibited the greatest nonlinearity and variability across participants. Substantial AP translations occurred in all segments (5.0 ± 0.3 mm) and exhibited more scatter and deviation from a nominally linear path compared to segmental extension. Maximum out-of-plane rotations (<1.91 deg) and translations (<0.94 mm) were small compared to the dominant motion in the sagittal plane. The demonstrated success in capturing continuous 3D in vivo lumbar intervertebral kinematics during functional tasks affords the possibility to create a baseline data set for evaluating the lumbar spinal function. The technique can be used to address the gaps in knowledge of lumbar kinematics, to improve the accuracy of the kinematic input into biomechanical models, and to support development of new disk replacement designs more closely replicating the natural lumbar biomechanics.

Crystal structure of the FAS1 domain of the hyaluronic acid receptor stabilin-2

2018 ◽  
Vol 74 (7) ◽  
pp. 695-701 ◽  
Author(s):  
Aleksandra Twarda-Clapa ◽  
Beata Labuzek ◽  
Dobroslawa Krzemien ◽  
Bogdan Musielak ◽  
Przemyslaw Grudnik ◽  
...  
Keyword(s):  
Hyaluronic Acid ◽  
Cancer Metastasis ◽  
Potential Role ◽  
Three Dimensional ◽  
Protein Fragments ◽  
Acid Receptor ◽  
X Ray ◽  
Insight Into

Recent research has identified a potential role of the hyaluronic acid receptor stabilin-2 (Stab2) in cancer metastasis. Stab2 belongs to a group of scavenger receptors and is responsible for the clearance of more than ten ligands, including hyaluronic acid (HA). In vivo experiments on mice have shown that the absence of Stab2, or its blocking by an antibody, effectively opposes cancer metastasis, which is accompanied by an increase in the level of circulating HA. Knowledge of ligand recognition and signal transduction by Stab2 is limited and no three-dimensional structures of any protein fragments of this receptor have been solved to date. Here, a high-resolution X-ray structure of the seventh FAS1 domain of Stab2 is reported. This structure provides the first insight into the Stab2 structure.

X-ray microtomography setup for absorption and diffraction tomography

2018 ◽  
Vol 84 (12) ◽  
pp. 32-39
Author(s):  
V. E. Asadchikov ◽  
A. V. Buzmakov ◽  
I. G. Dyachkova ◽  
D. A. Zolotov ◽  
Yu. S. Krivonosov ◽  
...  
Keyword(s):  
Three Dimensional ◽  
Research Centre ◽  
Diffraction Reflection ◽  
Dislocation Loops ◽  
X Ray ◽  
Silicon Crystals ◽  
Dimensional Reconstruction ◽  
Pure Cholesterol

The results of studying silicon single crystals and gallstones on a laboratory X-ray microtomograph with a spatial resolution of 10 µm (developed at the Federal Scientific Research Centre for «Crystallography and Photonics» of the Russian Academy of Sciences) are reviewed. The method of tomographic experiment included the use of a monochromatic «parallel beam» with subsequent three-dimensional reconstruction based on a set of two-dimensional projections. Topotomographic measurements were performed in the mode of rotation of the samples under study around the normal to the reflecting plane adjusted to the Laue diffraction reflection geometry, which made it possible to identify and study single dislocations in perfect silicon crystals. Simulation of the dislocation loops was carried out on the basis of numerical solution of the Takagi-Taupin equations. In-vitro microtomographic study of human gallstones revealed the layered structure of the gallstones which are close in composition to modifications of calcium carbonate. The internal structure of the stones is heterogeneous and contains numerous cavities and cracks formed upon their growth. At the same time, the evaluation of the porosity of gallstones is necessary, since the latter can affect the rate of stone dissolution in their treatment by litholytic methods. Linear attenuation coefficients of x-ray radiation of cholesterol-type gallstones were calculated from the measurement results. The good agreement of the experimentally obtained results and calculations based on tabular data for pure cholesterol is demonstrated which proved that the tomographic method can be used for in vivo diagnosis of cholesterol-type gallstones.

Synthesis and crystal structures of a 3-acetylated (20S,24S)-ocotillol-type saponin and its C-24 epimer

2017 ◽  
Vol 73 (6) ◽  
pp. 464-469 ◽  
Author(s):  
Juan Liu ◽  
Yang-Rong Xu ◽  
Xing-Si An ◽  
Gui-Ge Hou ◽  
Qing-Guo Meng
Keyword(s):  
Hydrogen Bonds ◽  
Three Dimensional ◽  
Water Molecules ◽  
X Ray Diffraction ◽  
X Ray ◽  
H Nmr ◽  
Dimensional Network ◽  
Crystal Packings ◽  
C Nmr

In order to study the in vivo protective effect on myocardial ischemia, (20S,24R)-epoxydammarane-12β,25-diol, (V), and (20S,24S)-epoxydammarane-12β,25-diol, (VI), were synthesized through a novel synthetic route. Two key intermediates, namely (20S,24R)-3-acetyl-20,24-epoxydammarane-3β,12β,25-triol, (III) [obtained as the hemihydrate, C32H54O5·0.5H2O, (IIIa), and the ethanol hemisolvate, C32H54O5·0.5C2H5OH, (IIIb), with identical conformations but different crystal packings], and (20S,24S)-3-acetyl-20,24-epoxydammarane-3β,12β,25-triol, C32H54O5, (IV), were obtained during the synthesis. The structures were confirmed by 1H NMR, 13C NMR and HRMS analyses, and single-crystal X-ray diffraction. Molecules of (IIIa) are extended into a two-dimensional network constructed with water molecules linked alternately through intermolecular O—H...O hydrogen bonds, which are further stacked into a three-dimensional network. Compound (IIIb) contains two completely asymmetric molecules, which are linked in a disordered manner through intermolecular C—H...O hydrogen bonds. While the crystal stacks in compound (IV) are linked via weak C—H...O hydrogen bonds, the hydrogen-bonded chains extend helically along the crystallographic b axis.

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