scholarly journals Determination of sex-related differences based on 3D reconstruction of the chinchilla (Chinchilla lanigera) vertebral column from MDCT scans

2017 ◽  
Vol 62 (No. 4) ◽  
pp. 204-210 ◽  
Author(s):  
S. Ozkadif ◽  
E. Eken ◽  
MO Dayan ◽  
K. Besoluk

This study was undertaken to obtain and analyse, on the basis of sex, three-dimensional (3D) reconstructions obtained by a 3D computer program from two-dimensional (2D) vertebral column sections taken by multidetector computed tomography (MDCT) images, in the chinchilla. A total of 16 adult chinchillas (Chinchilla lanigera) of both sexes were used. The MDCT images were taken under general anaesthesia, and were then transferred to a personal computer on which 3D reconstructions were carried out using a 3D modelling program (Mimics 13.1). The volume, surface area and vertebral body length of each vertebra (except caudal region) forming the vertebral column were measured from the 3D models created. The ratios (in percentage) of the measurements of each vertebra (except the sacral ones) forming the vertebral column region (cervical part, thoracic part, lumbar part) were determined for statistical analysis. We detected significant differences (P < 0.05) between sexes in all vertebrae forming the vertebral column of the chinchilla with respect to volume, surface area and vertebral body length, except for C6 and L1. This study is the first to carry out 3D reconstructions of data obtained from CT images in the chinchilla and the obtained results contribute to a more detailed understanding of the anatomy of this species. Our strategy may also be useful for the design of experiments exploring the vertebral column in domestic mammals and humans.

2018 ◽  
Vol 5 (8) ◽  
pp. 172307 ◽  
Author(s):  
Ramon S. Nagesan ◽  
Donald M. Henderson ◽  
Jason S. Anderson

The elongate-necked aquatic plesiosaurs existed for 135 Myr during the Mesozoic. The function of this elongate neck is a point of debate. Using computed tomography and three-dimensional (3D) modelling, the range of motion (ROM) of the plesiosaur Nichollssaura borealis neck was assessed. To quantify the ROM, the intervertebral mobility was measured along the cervical vertebral column. This was done by manipulating the 3D models in the lateral and dorsoventral directions during two trials. The first assessed the mean intervertebral ROM between pairs of cervical vertebrae along the entire column, and the second assessed ROM with reduced intervertebral spaces. The results suggest that there may be preference for lateral neck movements in N. borealis , which could correspond to an ecological function related to prey capture. This study demonstrates that 3D modelling is an effective tool for assessing function morphology for structures where no good modern analogue exists.


Author(s):  
Luis Marques ◽  
Josep Roca

The creation of 3D models of urban elements is extremely relevant for urbanists constituting digital archives and being especially useful for enriching maps and databases or reconstructing and analyzing objects/areas through time, building/recreating scenarios and implementing intuitive methods of interaction. The widespread data available online offer new opportunities to generate realistic 3D models without the need to go physically to the place. This chapter aims to demonstrate the potential 3D modeling and visualization/interaction of urban elements in the city for multiple purposes, and it is organized in four main topics: The first deals with the theoretical framework regarding the bases of the human perception of the spatial environment and the importance of 3D modelling. The second and third deal with technical procedures on terrestrial/aerial data acquisition and demonstrate alternatively data gathered online to generate 3D models for the visualization of urban elements of the city, and the fourth introduces 3D model visualization within an augmented reality environment.


2020 ◽  
Vol 501 (1) ◽  
pp. 564-575
Author(s):  
M I Gornostaev

ABSTRACT The paper presents the results of three-dimensional (3D) modelling of the structure and the emission of accretion columns formed above the surface of accreting strongly magnetized neutron stars under the circumstances when a pressure of the photons generated in the column base is enough to determine the dynamics of the plasma flow. On the foundation of numerical radiation hydrodynamic simulations, several 3D models of accretion column are constructed. The first group of the models contains spatially 3D columns. The corresponding calculations lead to the distributions of the radiation flux over the sidewalls of the columns which are not characterized by axial symmetry. The second group includes the self-consistent modelling of spectral radiative transfer and two-dimensional spatial structure of the column, with both thermal and bulk Comptonization taken into account. The changes in the structure of the column and the shape of X-ray continuum are investigated depending on physical parameters of the model.


2021 ◽  
Vol 14 (3) ◽  
pp. 28-39
Author(s):  
B.G. Guliev ◽  
◽  
B.K. Komyakov ◽  
A.E. Talyshinskii ◽  
◽  
...  

Introduction. 3D printing technology is being actively introduced into the urological practice. Apart from improving of patients counselling, this technology allows for improved planning end performance of surgery. Aim of study. To determine the current state of three-dimensional printing in the urological practice. Materials and methods. Embase, Medline, Google Scholar, Scopus databases were searched to find related publications until September 2020. Inclusion criteria were: the availability of the full article, the use of 3D models for teaching patients or residents, and their use in planning and performing surgery on patients over 18 years of age. Results. One hundred and ninety seven publications were included, of which 40 were selected for a further analysis. 11 articles were related to the study of the usefulness of printed models in counseling patients with urolithiasis, planning and training of retrograde lithotripsy and percutaneous nephrolithotripsy. In 20 articles, the printed model was used to counsel patients with renal neoplasms, planning and intraoperative navigation. In 9 papers, the results of the use of printed models in communication with patients with prostate tumor, in improving the determination of its localization and planning of the upcoming surgery were published. Conclusion. The creation of three-dimensional printed models is promising in urology. Despite the current limitations this field is becoming more accessible for both patients and doctors.


2020 ◽  
Vol 12 (17) ◽  
pp. 2676 ◽  
Author(s):  
Atsuko Fukunaga ◽  
John H. R. Burns

Underwater photogrammetry has been increasingly used in coral-reef research in recent years. Habitat metrics extracted from resulting three-dimensional (3D) reconstructions can be used to examine associations between the structural complexity of the reef habitats and the distribution of reef organisms. We created simulated 3D models of bare surface structures and 3D reconstructions of coral morphologies to investigate the behavior of various habitat metrics that were extracted from both Digital Elevation Models (DEMs) and 3D mesh models. Analyzing the resulting values provided us with important insights into how these metrics would compare with one another in the characterization of coral-reef habitats. Surface complexity (i.e., reef rugosity), fractal dimension extracted from DEMs and vector dispersion obtained from 3D mesh models exhibited consistent patterns in the ranking of structural complexity among the simulated bare surfaces and coral morphologies. The vector ruggedness measure obtained from DEMs at three different resolutions of 1, 2, and 4 cm effectively captured differences in the structural complexity among different coral morphologies. Profile curvature and planform curvature, on the other hand, were better suited to capture the structural complexity derived from surface topography such as walls and overhanging ledges. Our results indicate that habitat metrics extracted from DEMs are generally suitable when characterizing a relatively large plot of a coral reef captured from an overhead planar angle, while the 3D metric of vector dispersion is suitable when characterizing a coral colony or a relatively small plot methodically captured from various angles.


2017 ◽  
Vol 312 (2) ◽  
pp. L243-L257 ◽  
Author(s):  
Roman Grothausmann ◽  
Lars Knudsen ◽  
Matthias Ochs ◽  
Christian Mühlfeld

Grothausmann R, Knudsen L, Ochs M, Mühlfeld C. Digital 3D reconstructions using histological serial sections of lung tissue including the alveolar capillary network. Am J Physiol Lung Cell Mol Physiol 312: L243–L257, 2017. First published December 2, 2016; doi: 10.1152/ajplung.00326.2016 .—The alveolar capillary network (ACN) provides an enormously large surface area that is necessary for pulmonary gas exchange. Changes of the ACN during normal or pathological development or in pulmonary diseases are of great functional impact and warrant further analysis. Due to the complexity of the three-dimensional (3D) architecture of the ACN, 2D approaches are limited in providing a comprehensive impression of the characteristics of the normal ACN or the nature of its alterations. Stereological methods offer a quantitative way to assess the ACN in 3D in terms of capillary volume, surface area, or number but lack a 3D visualization to interpret the data. Hence, the necessity to visualize the ACN in 3D and to correlate this with data from the same set of data arises. Such an approach requires a large sample volume combined with a high resolution. Here, we present a technically simple and cost-efficient approach to create 3D representations of lung tissue ranging from bronchioles over alveolar ducts and alveoli up to the ACN from more than 1 mm sample extent to a resolution of less than 1 μm. The method is based on automated image acquisition of serially sectioned epoxy resin-embedded lung tissue fixed by vascular perfusion and subsequent automated digital reconstruction and analysis of the 3D data. This efficient method may help to better understand mechanisms of vascular development and pathology of the lung.


Proceedings ◽  
2019 ◽  
Vol 19 (1) ◽  
pp. 8
Author(s):  
Barbero-García ◽  
Lerma

Three-dimensional (3D) models are a useful tool for cranial deformation analysis in infants. The registration of the head 3D models to a known coordinate system is vital for the obtainment of parameters and indexes that quantify deformation. In this study, three registration methodologies have been tested based on the principal component analysis (PCA) without tie points, and PCA measuring manually two and three identified tie points. Results show that the approach using PCA plus three manually identified tie points provides enough accuracy for the given application.


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