scholarly journals Geometrical Properties of Skeletal Structures of Radiolarian Genus Didymocyrtis

2019 ◽  
pp. 237-244
Author(s):  
Takashi Yoshino ◽  
Atsushi Matsuoka ◽  
Naoko Kishimoto
Keyword(s):  
Spherical Surface ◽  
Skeletal Structure ◽  
X Ray ◽  
Geometrical Properties ◽  
Skeletal Structures ◽  
3D Data ◽  
Cortical Shell

This paper discusses the geometrical properties of a radiolarian skeletal structure, namely, that of genus Didymocyrtis. We characterized the evolution of skeletal structures and analyzed the structures using geometry. We defined two ratios in order to quantify the geometrical properties of Didymocyrtis and verified that the two ratios changed with their phylogenic evolution. We also used the 3D skeletal data of a specimen of species D. tetrathalamus, which was obtained through micro X-ray CT. The cortical shell obtained in the 3D data was projected onto a spherical surface, and we determined the centers of the pores. Our analysis revealed that the number of pores is approximately 200 and their distribution is not regular. We also determined that the column-like parts of the skeleton, which connect the inner and upper parts of the specimen, do not lie on a plane and their intervals are not equal. 

scholarly journals ROOT PHENOTYPING FROM X-RAY COMPUTED TOMOGRAPHY: SKELETON EXTRACTION

2021 ◽  
Vol XLIII-B4-2021 ◽  
pp. 417-422
Author(s):  
M. Herrero-Huerta ◽  
V. Meline ◽  
A. S. Iyer-Pascuzzi ◽  
A. M. Souza ◽  
M. R. Tuinstra ◽  
...  
Keyword(s):  
Computed Tomography ◽  
Root System ◽  
High Throughput ◽  
Skeletal Structure ◽  
Plant Phenotyping ◽  
Skeleton Extraction ◽  
X Ray ◽  
Digital Twin ◽  
Three Samples ◽  
Root Phenotyping

Abstract. Breakthrough imaging technologies are a potential solution to the plant phenotyping bottleneck in marker-assisted breeding and genetic mapping. X-Ray CT (computed tomography) technology is able to acquire the digital twin of root system architecture (RSA), however, advances in computational methods to digitally model spatial disposition of root system networks are urgently required.We extracted the root skeleton of the digital twin based on 3D data from X-ray CT, which is optimized for high-throughput and robust results. Significant root architectural traits such as number, length, growth angle, elongation rate and branching map can be easily extracted from the skeleton. The curve-skeleton extraction is computed based on a constrained Laplacian smoothing algorithm. This skeletal structure drives the registration procedure in temporal series. The experiment was carried out at the Ag Alumni Seed Phenotyping Facility (AAPF) at Purdue University in West Lafayette (IN, USA). Three samples of tomato root at 2 different times and three samples of corn root at 3 different times were scanned. The skeleton is able to accurately match the shape of the RSA based on a visual inspection.The results based on a visual inspection confirm the feasibility of the proposed methodology, providing scalability to a comprehensive analysis to high throughput root phenotyping.

scholarly journals 3D immersive visualization of micro-computed tomography and XRD texture datasets

2019 ◽  
Vol 34 (2) ◽  
pp. 97-102
Author(s):  
M. A. Rodriguez ◽  
T. T. Amon ◽  
J. J. M. Griego ◽  
H. Brown-Shaklee ◽  
N. Green
Keyword(s):  
Computed Tomography ◽  
Texture Analysis ◽  
Mechanical Strain ◽  
Three Dimensional ◽  
Multidimensional Analysis ◽  
Micro Computed Tomography ◽  
X Ray ◽  
3D Data ◽  
Pole Figures ◽  
Ct Data

Advancements in computer technology have enabled three-dimensional (3D) reconstruction, data-stitching, and manipulation of 3D data obtained on X-ray imaging systems such as micro-computed tomography (μ-CT). Likewise, intuitive evaluation of these 3D datasets can be enhanced by recent advances in virtual reality (VR) hardware and software. Additionally, the generation, viewing, and manipulation of 3D X-ray diffraction datasets, such as pole figures employed for texture analysis, can also benefit from these advanced visualization techniques. We present newly-developed protocols for porting 3D data (as TIFF-stacks) into a Unity gaming software platform so that data may be toured, manipulated, and evaluated within a more-intuitive VR environment through the use of game-like controls and 3D headsets. We demonstrate this capability by rendering μ-CT data of a polymer dogbone test bar at various stages of in situ mechanical strain. An additional experiment is presented showing 3D XRD data collected on an aluminum test block with vias. These 3D XRD data for texture analysis (χ, ϕ, 2θ dimensions) enables the viewer to visually inspect 3D pole figures and detect the presence or absence of in-plane residual macrostrain. These two examples serve to illustrate the benefits of this new methodology for multidimensional analysis.

The Study on the Residual Stresses of Circular Sawblades with Spherical Surface Pressed Many Spots

2010 ◽  
Vol 29-32 ◽  
pp. 1323-1326
Author(s):  
Qiu Yun Mo ◽  
Zhan Kuan Zhang ◽  
Hao Li
Keyword(s):  
Stress Distribution ◽  
Residual Stresses ◽  
Thermal Stresses ◽  
Distribution Curve ◽  
Spherical Surface ◽  
Comprehensive Analysis ◽  
X Ray ◽  
Circular Saws

This paper is a comprehensive analysis about circular saws exerted the inertia stresses, thermal stresses and residual stresses inducted roll and hammer tensioning in working procedures. And analyze the weaknesses and the advantages of two methods of roll tensioning and hammer tensioning. In order to take advantages to compensate the weaknesses to bring forward a new tensioning method compressed many areas i.e. the tensioning spots compressed by using the roll-head whose surface is spherical, cylindrical or cone. The X-ray stress-checking instrument is used to test the residual stresses in the tensioned circular sawblades compressed on many spots. The result explains the stress distribution curve is very ideal and the residual stresses by tensioning almost offset the total inertia and thermal stresses inducted in the work. This explains it is a new circular tensioning method with developing value by compressing many spots. It exists in certain residual stresses on the rim of the sawblade’s central bore, outside and the areas near the slot bore because of the influence of the machine processes.

Micro-X-ray fluorescence-based comparison of skeletal structure and P, Mg, Sr, O and Fe in a fossil of the cold-water coral Desmophyllum sp., NW Pacific

2013 ◽  
Vol 34 (1) ◽  
pp. 1-9 ◽  
Author(s):  
Toshihiro Yoshimura ◽  
Atsushi Suzuki ◽  
Yusuke Tamenori ◽  
Hodaka Kawahata
Keyword(s):  
Cold Water ◽  
Skeletal Structure ◽  
X Ray ◽  
Water Coral

Damage Investigation in Aluminium Alloys by X Ray Tomography

2006 ◽  
Vol 519-521 ◽  
pp. 821-827 ◽  
Author(s):  
Éric Maire ◽  
J.C. Grenier ◽  
L. Babout
Keyword(s):  
Spherical Shape ◽  
Three Dimensions ◽  
Ex Situ ◽  
X Ray ◽  
Plane Strain Tension ◽  
3D Data ◽  
Tension Tests ◽  
Respective Contribution ◽  
Damage Investigation

X-ray tomography allows the microstruture of aluminum alloys to be imaged non destructively in three dimensions (3D). This paper shows different examples of the use of this technique for the quantification of damage in model and industrial Al based materials. The model materials are used to setup the technique. The spherical shape of their inclusions makes it easy to compare the measurements with the prediction of standard model for damage. The industrial materials are characterized during in situ tensile but also ex situ bulging and plane strain tension tests. The respective contribution of initiation and growth of damage is measured separately and discussed. The 3D data are also used to quantify the anisotropy of the effect of damage.

scholarly journals A New Straightforward Method for Automated Segmentation of Trabecular Bone from Cortical Bone in Diverse and Challenging Morphologies

2021 ◽  
Author(s):  
Eva C. Herbst ◽  
Alessandro A. Felder ◽  
Lucinda A. E. Evans ◽  
Sara Ajami ◽  
Behzad Javaheri ◽  
...  
Keyword(s):  
Cortical Bone ◽  
Skeletal Structure ◽  
Automated Segmentation ◽  
Micro Computed Tomography ◽  
X Ray ◽  
Straightforward Method ◽  
Successful Separation ◽  
And Function ◽  
Automated Protocol ◽  
User Friendly

AbstractMany physiological, biomechanical, evolutionary and clinical studies that explore skeletal structure and function require successful separation of trabecular from cortical compartments of a bone that has been imaged by X-ray micro-computed tomography (microCT) prior to analysis. Separation is often time-consuming, involves user bias and needs manual sub-division of these two similarly radio-opaque compartments. We have developed an objective, automated protocol which reduces user bias and enables straightforward, user-friendly segmentation of trabecular from cortical bone without requiring sophisticated programming expertise. This method can conveniently be used as a “recipe” in commercial programmes (Avizo herein) and applied to a variety of datasets. Here, we characterise and share this recipe, and demonstrate its application to a range of murine and human bone types, including normal and osteoarthritic specimens, and bones with distinct embryonic origins and spanning a range of ages. We validate the method by testing inter-user bias during the scan preparation steps and confirm utility in the architecturally challenging analysis of growing murine epiphyses. We also report details of the recipe, so that other groups can readily re-create a similar method in open access programs. Our aim is that this method will be adopted widely to create a more standardized and time efficient method of segmenting trabecular and cortical bone.

scholarly journals Constraining the geometry of the nuclear wind in PDS 456 using a novel emission model

2018 ◽  
Vol 619 ◽  
pp. A149 ◽  
Author(s):  
A. Luminari ◽  
E. Piconcelli ◽  
F. Tombesi ◽  
L. Zappacosta ◽  
F. Fiore ◽  
...  
Keyword(s):  
Monte Carlo Model ◽  
High Energy ◽  
Mean Value ◽  
Feedback Mechanism ◽  
Host Galaxy ◽  
Opening Angle ◽  
Emission Model ◽  
Host Galaxies ◽  
X Ray ◽  
Geometrical Properties

Context. Outflows from active galactic nuclei (AGN) are often invoked to explain the co-evolution of AGN and their host galaxies, and the scaling relations between the central black hole mass and the bulge velocity dispersion. Nuclear winds are often seen in the X-ray spectra through Fe K shell transitions and some of them are called ultra fast outflows (UFOs) due to their high velocities, up to some fractions of the speed of light. If they were able to transfer some percentage of the AGN luminosity to the host galaxy, this might be enough to trigger an efficient feedback mechanism. Aims. We aim to establish new constraints on the covering fraction and on the kinematic properties of the UFO in the powerful (Lbol ∼ 1047 erg s−1) quasar PDS 456, an established Rosetta stone for studying AGN feedback from disk winds. This will allow us to estimate the mass outflow rate and the energy transfer rate of the wind, which are key quantities to understand the potential impact on the host galaxy. Methods. We analyze two sets of simultaneous XMM-Newton and NuSTAR observations taken in September 2013 and reported in Nardini et al. (2015, Science, 347, 860) as having similar broadband spectral properties. We fit the Fe K features with a P-Cygni profile between 5 and 14 keV, using a novel Monte Carlo model for the WINd Emission (WINE). Results. We find an outflow velocity ranging from 0.17 to 0.28 c, with a mean value of 0.23 c. We obtain an opening angle of the wind of 71−8+13 deg and a covering fraction of 0.7−0.3+0.2, suggesting a wide-angle outflow. We check the reliability of the WINE model by performing extensive simulations of joint XMM-Newton and NuSTAR observations. Furthermore, we test the accuracy of the WINE model in recovering the geometrical properties of UFOs by simulating observations with the forthcoming Advanced Telescope for High-Energy Astrophysics (ATHENA) in the X-ray band.

scholarly journals 4D Structural Root Architecture Modeling From Digital Twins By X-Ray Computed Tomography

2021 ◽  
Author(s):  
Monica Herrero ◽  
Valerian Meline ◽  
Anjali S. Iyer-Pascuzzi ◽  
Augusto M. Souza ◽  
Mitchell R. Tuinstra ◽  
...  
Keyword(s):  
Computed Tomography ◽  
High Throughput ◽  
Lateral Roots ◽  
Skeletal Structure ◽  
Coefficient Of Determination ◽  
Plant Phenotyping ◽  
X Ray ◽  
Digital Twin ◽  
Three Samples ◽  
Over Time

Abstract BackgroundBreakthrough imaging technologies are a potential solution to address the plant phenotyping bottleneck regarding marker-assisted breeding and genetic mapping. X-Ray CT (computed tomography) technology is able to acquire the digital twin of root system architecture (RSA) but computational methods to quantify RSA traits and analyze their changes over time are limited. RSA traits extremely affect agricultural productivity. We develop a spatial-temporal root architectural modeling method based on 4D data from X-ray CT. This novel approach is optimized for high-throughput phenotyping considering the cost-effective time to process the data and the accuracy and robustness of the results. Significant root architectural traits, including root elongation rate, number, length, growth angle, height, diameter, branching map, and volume of axial and lateral roots are extracted from the model based on the digital twin. Our pipeline is divided into two major steps: (i) first, we compute the curve-skeleton based on a constrained Laplacian smoothing algorithm. This skeletal structure determines the registration of the roots over time; (ii) subsequently, the RSA is robustly modeled by a cylindrical fitting. The experiment was carried out at the Ag Alumni Seed Phenotyping Facility (AAPF) from Purdue University in West Lafayette (IN, USA). ResultsRoots from three samples of tomato plants at two different times and three samples of corn plants at three different times were scanned. Regarding the first step, the PCA analysis of the skeleton is able to accurately and robustly register temporal roots. From the second step, the volume from the cylindrical model was compared against the root digital twin, reaching a coefficient of determination (R2) of 0.84 and a P < 0.001. ConclusionsThe results confirm the feasibility of the proposed methodology, providing scalability to a comprehensive analysis to high throughput root phenotyping.

X-ray tomographic image of a deposit on a spherical surface

JETP Letters ◽  
2012 ◽  
Vol 94 (9) ◽  
pp. 680-683 ◽  
Author(s):  
I. V. Yakimchuk ◽  
A. V. Buzmakov ◽  
A. V. Andreev ◽  
V. E. Asadchikov
Keyword(s):  
Spherical Surface ◽  
Tomographic Image ◽  
X Ray
Sign in / Sign up

Export Citation Format

Share Document