scholarly journals Three-dimensional mobility and muscle attachments in the pectoral limb of the Triassic cynodontMassetognathus pascuali

2017 ◽  
Author(s):  
Phil H. Lai ◽  
Andrew A. Biewener ◽  
Stephanie E. Pierce
Keyword(s):  
Body Wall ◽  
Three Dimensional ◽  
Detailed Examination ◽  
The Body ◽  
Three Dimensions ◽  
Glenoid Fossa ◽  
Micro Computed Tomography ◽  
Skeletal Morphology ◽  
Shoulder Muscles ◽  
Maximum Range

ABSTRACTThe musculoskeletal configuration of the mammalian pectoral limb has been heralded as a key anatomical feature leading to the adaptive radiation of mammals, but limb function in the cynodont outgroup remains unresolved. Conflicting reconstructions of abducted and adducted posture are based on mutually-incompatible interpretations of ambiguous osteology. We reconstruct the pectoral limb of the Triassic non-mammalian cynodontMassetognathus pascualiin three dimensions, by combining skeletal morphology from micro-computed tomography with muscle anatomy from an extended extant phylogenetic bracket. Conservative tests of maximum range of motion suggest a degree of girdle mobility, as well as substantial freedom at the shoulder and the elbow joints. The glenoid fossa supports a neutral pose in which the distal end of the humerus points 45° posterolaterally from the body wall, intermediate between classically “sprawling” and “parasagittal” limb postures.Massetognathusis reconstructed as having a near-mammalian complement of shoulder muscles, including an incipient rotator cuff (m. subscapularis, m. infraspinatus, m. supraspinatus, and m. teres minor). Based on close inspection of the morphology of the glenoid fossa, we hypothesize a posture-driven scenario for the evolution of the therian ball-and-socket shoulder joint. The musculoskeletal reconstruction presented here provides the anatomical scaffolding for more detailed examination of locomotor evolution in the precursors to mammals.

scholarly journals Three-dimensional simulation of the Caenorhabditis elegans body and muscle cells in liquid and gel environments for behavioural analysis

2018 ◽  
Vol 373 (1758) ◽  
pp. 20170376 ◽  
Author(s):  
Andrey Palyanov ◽  
Sergey Khayrulin ◽  
Stephen D. Larson
Keyword(s):  
Caenorhabditis Elegans ◽  
Muscle Activation ◽  
Body Wall ◽  
Particle System ◽  
Three Dimensional ◽  
Muscle Cells ◽  
The Body ◽  
C Elegans ◽  
Muscle Activation Patterns ◽  
Simulation Engine

To better understand how a nervous system controls the movements of an organism, we have created a three-dimensional computational biomechanical model of the Caenorhabditis elegans body based on real anatomical structure. The body model is created with a particle system–based simulation engine known as Sibernetic, which implements the smoothed particle–hydrodynamics algorithm. The model includes an elastic body-wall cuticle subject to hydrostatic pressure. This cuticle is then driven by body-wall muscle cells that contract and relax, whose positions and shape are mapped from C. elegans anatomy, and determined from light microscopy and electron micrograph data. We show that by using different muscle activation patterns, this model is capable of producing C. elegans -like behaviours, including crawling and swimming locomotion in environments with different viscosities, while fitting multiple additional known biomechanical properties of the animal.  This article is part of a discussion meeting issue ‘Connectome to behaviour: modelling C. elegans at cellular resolution’.

scholarly journals Micro-CT study of Middle Ordovician Spumellaria (radiolarians) from western Newfoundland, Canada

2020 ◽  
Vol 94 (3) ◽  
pp. 417-435 ◽  
Author(s):  
Sarah Kachovich ◽  
Jonathan C. Aitchison
Keyword(s):  
Computed Tomography ◽  
Three Dimensional ◽  
Detailed Examination ◽  
Micro Ct ◽  
Micro Computed Tomography ◽  
Lower Paleozoic ◽  
X Ray ◽  
Middle Ordovician ◽  
Radiolarian Assemblage ◽  
Taxonomic Groups

AbstractA new, previously undescribed Middle Ordovician (middle Darriwilian: Dw2) radiolarian assemblage has been recovered from the Table Cove Formation at Piccadilly Quarry, western Newfoundland. Constituents of the fauna described herein are both distinctive and exceptionally well preserved. Three-dimensional X-ray micro-computed tomography (μ-CT) is used to make a detailed examination of four key spumellarian specimens. This technology enables visualization of hitherto ambiguous details of the internal morphologies of key lower Paleozoic taxonomic groups, among which a lack of knowledge has impeded resolution of higher taxonomic rankings.

scholarly journals Middle Ordovician (middle Darriwilian) Archaeospicularia and Entactinaria (radiolarians) from the Table Cove Formation, Piccadilly Quarry, Newfoundland, Canada

2021 ◽  
pp. 1-31
Author(s):  
Sarah Kachovich ◽  
Jonathan C. Aitchison
Keyword(s):  
Computed Tomography ◽  
New Species ◽  
Three Dimensional ◽  
Detailed Examination ◽  
Micro Computed Tomography ◽  
Lower Paleozoic ◽  
X Ray ◽  
Middle Ordovician ◽  
Radiolarian Assemblage ◽  
Taxonomic Groups

Abstract New, distinctive, well-preserved and previously undescribed constituents of a Middle Ordovician (middle Darriwilian, Dw2) radiolarian assemblage from the Table Cove Formation in Newfoundland are described. Three-dimensional X-ray micro-computed tomography (μ-CT) facilitates detailed examination of key specimens revealing hitherto unknown details of the internal morphologies of key lower Paleozoic taxonomic groups, among which a lack of knowledge has previously impeded resolution of higher taxonomic rankings. Twenty-seven archaeospiculid and entactinarian taxa are described and illustrated including six new species: Westernbrookia polygonata n. sp., Neopalaeospiculum piccadilliensis n. sp., Ramuspiculum laxum n. sp. Spongentactinia nazarovi n. sp., Aspiculum irregulare n. sp., and Nyfrieslandia ramosissima n. sp. The investigation extends the known ranges of the species: Pararcheoentactinia reedae Won and Iams, 2002; Sphaeroentactinia robusta Won and Iams, 2015; Varispiculum ectospiculatum Won and Iams, 2015; and Svalbardospiculum multifurcatum (Won, Iams, and Reed, 2005), together with the genus Echidnina to the mid-Darriwilian. UUID: http://zoobank.org/74826b7b-bb86-45d5-ad23-e6e65e0706df.

Structure and mechanics of starfish body wall

1989 ◽  
Vol 147 (1) ◽  
pp. 53-89 ◽  
Author(s):  
P. O'Neill
Keyword(s):  
Stress Relaxation ◽  
Neural Control ◽  
Body Wall ◽  
Three Dimensional ◽  
Polarized Light ◽  
The Body ◽  
Strain Rates ◽  
Collagen Fibres ◽  
Young’S Moduli ◽  
Tension Tests

The structure of the dorsal body wall of the starfish Echinaster spinulosus was studied using polarized light microscopy of frozen tissues, scanning electron microscopy and histology. The collagen fibres of the body wall form a three-dimensional orthogonal web. Voids in the web contain ossicles and papulae. The orthogonal web delivers dimensional stability but allows shear necessary for ray torsion. The ossicles and fibres interact to load the fibres in tension and the ossicles in compression. Strain rates of the dorsal body wall were measured on live animals during typical movements. Uniaxial tension tests of the body wall yielded Young's moduli of 267 MPa (longitudinal), 249 MPa (transverse) and 353 MPa (bias); curves were essentially linear. The body wall was approximately linearly viscoelastic and showed hysteresis at 0.01 Hz. Stress relaxation over five decades of time (in seconds) yielded relaxation spectra with peaks in relaxation time at 2.96-3.35, depending on test direction. Stress relaxation caused the connective tissue to soften. The surface of fractured stress-relaxed tissue revealed wispy, dissociated fibril tufts, whereas unrelaxed fractures produced blunt-ended fibre bundles. Neural control was necessary for body wall integrity.

Three-dimensional study of vestibular anatomy as it relates to the stapes footplate and its clinical implications: an augmented reality development

2019 ◽  
Vol 133 (03) ◽  
pp. 187-191 ◽  
Author(s):  
P Mukherjee ◽  
K Cheng ◽  
I Curthoys
Keyword(s):  
Computed Tomography ◽  
Augmented Reality ◽  
Surgical Intervention ◽  
Three Dimensional ◽  
Three Dimensions ◽  
Limited Information ◽  
Micro Computed Tomography ◽  
Membranous Labyrinth ◽  
Stapes Footplate ◽  
Temporal Bones

AbstractBackgroundThe anatomy of the membranous labyrinth within the vestibule has direct implications for surgical intervention. The anatomy of the otoliths has been studied, but there is limited information regarding their supporting connective tissue structures such as the membrana limitans in humans.MethodsOne guinea pig and 17 cadaveric human temporal bones were scanned using micro computed tomography, after staining with 2 per cent osmium tetroxide and preservation with Karnovsky's solution, with a resolution from 1 µm to 55 µm. The data were analysed using VGStudio Max software, rendered in three-dimensions and published in augmented reality.ResultsIn 50 per cent of ears, the membrana limitans attached directly to the postero-superior part of the stapes footplate. If attachments were present in one ear, they were present bilaterally in 100 per cent of cases.ConclusionMicro computed tomography imaging allowed three-dimensional assessment of the inner ear. Such assessments are important as they influence the surgical intervention and the evolution of future innovations.

scholarly journals 3D Muscle Architecture of the Pectoral Muscles of European Starling (Sturnus vulgaris)

2019 ◽  
Vol 1 (1) ◽  
Author(s):  
S P Sullivan ◽  
F R McGechie ◽  
K M Middleton ◽  
C M Holliday
Keyword(s):  
Fiber Tracking ◽  
Sturnus Vulgaris ◽  
European Starling ◽  
Muscle Architecture ◽  
The Body ◽  
Three Dimensions ◽  
Accurate Estimation ◽  
Pectoral Girdle ◽  
Micro Computed Tomography ◽  
Model Quality

Abstract Avian flight is achieved through a number of modifications to the body, including the pectoral girdle, yet little is known about the architecture of the pectoral musculature. Muscle architecture is a critical variable in determining the biomechanical function of the vertebrate musculoskeletal system; however, accurate three-dimensional (3D) understanding of muscle architecture has been historically difficult to acquire. Here, we present a musculoskeletal model of a European starling (Sturnus vulgaris) pectoral girdle generated from iodine contrast-enhanced micro-computed-tomography (CT) data and 3D fiber tracking analysis. We used a template-based fiber-tracking algorithm to reconstruct muscle fibers in 3D based on grayscale differences in CT images, which allowed us to estimate fascicle lengths, pennation angles, muscle volumes, and physiological cross-sectional area. Our modeled muscles were qualitatively accurate; however, quantitative muscle architecture data differed between digital and traditional gross-dissection methods reflecting the complex organization of the tissue and differing natures of data collection. We found that model quality is affected by the resolution of CT image data and the fiber-tracking program’s input parameters. Nonetheless, digital fiber tracking offers numerous advantages over gross-dissection methods, most importantly, the ability to visualize and quantify entire muscles in three-dimensions, yielding a much more accurate estimation of whole muscle architecture.

scholarly journals Comparative analysis of current 3D printed acetabular titanium implants

2019 ◽  
Vol 5 (1) ◽  
Author(s):  
Lorenzo Dall’Ava ◽  
Harry Hothi ◽  
Johann Henckel ◽  
Anna Di Laura ◽  
Paul Shearing ◽  
...  
Keyword(s):  
Outer Surface ◽  
Three Dimensional ◽  
Coordinate Measuring Machine ◽  
Titanium Implants ◽  
The Body ◽  
Lattice Structures ◽  
Micro Computed Tomography ◽  
Solid Region ◽  
3D Printed ◽  
Measuring Machine

Abstract Background The design freedom allowed by three-dimensional (3D) printing enables the production of acetabular off-the-shelf cups with complex porous structures. The only studies on these designs are limited to clinical outcomes. Our aim was to analyse and compare the designs of different 3D printed cups from multiple manufacturers (Delta TT, Trident II Tritanium and Mpact 3D Metal). Methods We analysed the outer surface of the cups using scanning electron microscopy (SEM) and assessed clinically relevant morphometric features of the lattice structures using micro-computed tomography (micro-CT). Dimensions related to the cup wall (solid, lattice and overall thickness) were also measured. Roundness and roughness of the internal cup surface were analysed with coordinate measuring machine (CMM) and optical profilometry. Results SEM showed partially molten titanium beads on all cups, significantly smaller on Trident II (27 μm vs ~ 70 μm, p < 0.0001). We found a spread of pore sizes, with median values of 0.521, 0.841 and 1.004 mm for Trident II, Delta TT and Mpact, respectively. Trident II was also significantly less porous (63%, p < 0.0001) than the others (Delta TT 72.3%, Mpact 76.4%), and showed the thinnest lattice region of the cup wall (1.038 mm, p < 0.0001), while Mpact exhibited the thicker solid region (4.880 mm, p < 0.0044). Similar roundness and roughness of the internal cup surfaces were found. Conclusion This was the first study to compare the designs of different 3D printed cups. A variability in the morphology of the outer surface of the cups and lattice structures was found. The existence of titanium beads on 3D printed parts is a known by-product of the manufacturing process; however, their prevalence on acetabular cups used in patients is an interesting finding, since these beads may potentially be released in the body.

A variational principle for three-dimensional interactions between water waves and a floating rigid body with interior fluid motion

2019 ◽  
Vol 866 ◽  
pp. 630-659 ◽  
Author(s):  
Hamid Alemi Ardakani
Keyword(s):  
Variational Principle ◽  
Rigid Body ◽  
Water Waves ◽  
Fluid Motion ◽  
Three Dimensional ◽  
Rigid Body Dynamics ◽  
The Body ◽  
Three Dimensions ◽  
Fluid Sloshing ◽  
Gravity Driven

A variational principle is given for the motion of a rigid body dynamically coupled to its interior fluid sloshing in three-dimensional rotating and translating coordinates. The fluid is assumed to be inviscid and incompressible. The Euler–Poincaré reduction framework of rigid body dynamics is adapted to derive the coupled partial differential equations for the angular momentum and linear momentum of the rigid body and for the motion of the interior fluid relative to the body coordinate system attached to the moving rigid body. The variational principle is extended to the problem of interactions between gravity-driven potential flow water waves and a freely floating rigid body dynamically coupled to its interior fluid motion in three dimensions.

Space Positioning of the 5-DOF Robotic Excavator

2011 ◽  
Vol 130-134 ◽  
pp. 3531-3535
Author(s):  
Xi Hua Xie ◽  
Liang Zhou ◽  
Qing Hua He
Keyword(s):  
Coordinate Transformation ◽  
Dimensional Space ◽  
Kinematic Model ◽  
Three Dimensional ◽  
Transformation Matrix ◽  
The Body ◽  
Three Dimensions ◽  
Angle Sensor ◽  
Robotic Excavator ◽  
Space Angle

The carriage positioning of excavator in three-dimensions (3-D) is the precondition of the robotic excavator starting roboticized works. In order to get the carriage position of excavator in three-dimensional space, angle sensors of such joints as bucket, arm, boom, and boom deflection are brought to bear. At the same time, a 2D-inclination sensor is introduced to check the list and pitch angles of the platform, and a rotatory angle sensor is introduced to check swing angle of the platform. And a laser receiver was mounted on the arm to measure the relative height of the arm to the laser beam from ground sender. Then the kinematic model is established, the coordinate transformation matrix of carriage positioning is formulated, and the height of the body relative to the ground is gotten. As a result, the coordinate transformation matrix of the bucket relative to the ground and the digging depth are formulated. That makes the excavator orient bucket precisely and set excavation depth exactly, and make automotive elaborate excavation come true.

An aid to the detailed examination of salps [Tunicata: Salpidae]

1965 ◽  
Vol 45 (3) ◽  
pp. 679-681 ◽  
Author(s):  
P. Foxton
Keyword(s):  
Detailed Examination ◽  
Body Cavity ◽  
The Body ◽  
Three Dimensions

A method is described for staining the musculature of preserved salps with Rose Bengale and reforming their natural shape by injecting the body cavity with molten agar. Compared with normal preserved material, specimens prepared in this way are easy to handle, more lifelike in appearance and the detailed arrangement of their musculature is clearly differentiated in three dimensions.

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