scholarly journals "The orchids of the animal kingdom": tackling functional anatomy and phenotypic plasticity of ant nest beetles (Carabidae: Paussus) using 3D models generated by Micro-Computed Tomography (µ-CT)

2019 ◽  
Vol 2 ◽  
Author(s):  
Francesco Simone Mensa ◽  
Federica Spani ◽  
Andrea Di Giulio
Keyword(s):  
Computed Tomography ◽  
Geometric Morphometrics ◽  
Cross Sections ◽  
High Performance ◽  
Imaging Techniques ◽  
Functional Anatomy ◽  
3D Models ◽  
The Body ◽  
Body Parts ◽  
Micro Computed Tomography

The genus Paussus is a highly specialized, charismatic group of ground beetles (Carabidae) classified in the subfamily Paussinae. All species of Paussus are obligate myrmecophiles (associates of ants). As with many other myrmecophilous or termitophilous beetles, Paussus have undergone extreme phenotypic adaptations for life with ants, at the level of head, antennae, and prothorax. Host data suggest that Paussus species are likely to be species-specific ant parasites, and the structural modifications of antennae and other body parts are likely under selection by their host ants. Investigating anatomical structures have been fundamental to better understand living organisms, and their interplay with the surrounding environment, which could induce significant morphological variation. In the last few years, bio-imaging techniques paired with geometric morphometrics (GM) overcame the limits of traditional anatomical studies, becoming widely non-invasive and highly informative for both internal and external characters. The use of Computed Tomography (CT) scanners definitively allowed to advance in the knowledge of either known or neglected biological structures. For this project, we used X-ray micro-computed tomography, in order to acquire 2D serial, cross-sections of various paussines samples, with a resolution between 0.954 and 2.44 micrometers. The 2D images in high resolution are then processed using a high-performance computer system and Thermo Scientific™ Amira™ Software and Thermo Scientific™ Avizo™ Software for the reconstruction of 3D models. With these models, we will be able to conduct a morphological study of the most variable parts in the body of the genus Paussus using 3D geometric morphometrics (3D GM), as these integrative techniques allows to describe in a quantitative way even subtle differences between structures, so as to determine whether the striking diversity of phenotypes is caused by the host or by other factors, overlapping the results obtained with the molecular part of phylogeny. These innovative practices help to deepen the meaning of shape in insect biology, from both structural and evolutionary views. They will allow, in particular, to describe the relationship between phylogeny and functional morphology in the extremely variable species of the subfamily Paussinae.

Morphology and Affinities of Ampelocissites Seeds (Vitaceae: Ampelopsis clade) from the Paleogene of Texas, USA

2020 ◽  
Vol 45 (3) ◽  
pp. 478-482
Author(s):  
Steven R. Manchester
Keyword(s):  
Computed Tomography ◽  
Cross Sections ◽  
Seed Coat ◽  
Ct Scanning ◽  
Seed Morphology ◽  
Early Eocene ◽  
Micro Computed Tomography ◽  
X Ray ◽  
Fossil Seeds ◽  
Fossil Genus

Abstract—The type material on which the fossil genus name Ampelocissites was established in 1929 has been reexamined with the aid of X-ray micro-computed tomography (μ-CT) scanning and compared with seeds of extant taxa to assess the relationships of these fossils within the grape family, Vitaceae. The specimens were collected from a sandstone of late Paleocene or early Eocene age. Although originally inferred by Berry to be intermediate in morphology between Ampelocissus and Vitis, the newly revealed details of seed morphology indicate that these seeds represent instead the Ampelopsis clade. Digital cross sections show that the seed coat maintains its thickness over the external surfaces, but diminishes quickly in the ventral infolds. This feature, along with the elliptical chalaza and lack of an apical groove, indicate that Ampelocissites lytlensis Berry probably represents Ampelopsis or Nekemias (rather than Ampelocissus or Vitis) and that the generic name Ampelocissites may be useful for fossil seeds with morphology consistent with the Ampelopsis clade that lack sufficient characters to specify placement within one of these extant genera.

scholarly journals All Our Eggs In One Basket: Challenges of High Resolution X-Ray Micro-Computed Tomography of Great Auk Pinguinus impennis Eggshell

2018 ◽  
Vol 2 ◽  
pp. e25794
Author(s):  
Douglas Russell ◽  
Arianna Bernucci ◽  
Amy Scott-Murray ◽  
Duncan Jackson ◽  
Farah Ahmed ◽  
...  
Keyword(s):  
Computed Tomography ◽  
High Resolution ◽  
Structured Light ◽  
3D Models ◽  
Breeding Ecology ◽  
Micro Computed Tomography ◽  
History Museum ◽  
X Ray ◽  
X Ray Imaging ◽  
Scan Data

High resolution X-ray micro-computed tomography gives the ability to research objects in unprecedented detail in 3D without damaging them but applying these new techniques to specimens can be complex. In 2017 the Natural History Museum (NHM), London embarked on a ground-breaking project with University of Sheffield to compare extinct Great Auk Pinguinus impennis eggshell microstructure to that of their extant relatives to gain new insight into their breeding ecology. NHM has a ZEISS Xradia 520 Versa X-ray microscope capable of submicron X-ray imaging in 3D but using it required supporting and moving complete eggshells within the confined, potentially harsh, mechanised environment of the microscope without risk. Ensuring the correct position and orientation of each egg to image nine distinct areas on the eggshell was also a challenge. Collaboration with colleagues in the NHM Conservation and Imaging & Analysis Centres developed a bespoke solution to hold and protect the eggs during scanning. All six NHM Great Auk eggshells and the inside of the microscope were surface scanned using a handheld structured light scanner. Scan data produced 3D models from which accurate 3D printed plastic replicas were made of the three Great Auk eggs prioritised for research. Each replica was used to mould a two-part, custom-built, case for each egg constructed from conservation grade epoxy putty and lined with polyethylene foam. This provided close-fitting, durable cases which could be used for the 6-month duration of the project. Each case enclosed its matching Great Auk egg entirely and had the advantage of being rock-hard, electrically insulating and water, heat and chemical resistant. A system of three, interchangeable, tailor-made mounting brackets were designed that married with the cases and held them safely and precisely inside the microscope at the correct angles and positions for imaging. The structured light scan of the inside of the microscope was used to model the necessary rotational movements of the cases and brackets inside the scanner, ensuring that all movements had sufficient clearance to avoid risk of impact. This system successfully protected the fragile c. 200 year old eggs throughout 70 scanning sessions. This provides a methodology for high resolution X-ray micro-computed tomography imaging of any similarly sized, fragile, object.

scholarly journals CALS Technologies in Mechanical Engineering Using the Example of Developing Three-Dimensional Models of Typical Products

2020 ◽  
Vol 26 (4) ◽  
pp. 637-649
Author(s):  
A. A. Popova ◽  
◽  
I. N. Shubin ◽  
R. E. Aliev ◽  
◽  
...  
Keyword(s):  
Complex Structure ◽  
Three Dimensional ◽  
3D Models ◽  
Machine Building ◽  
The Body ◽  
Body Parts ◽  
3D Cad ◽  
Cad System ◽  
Dimensional Models ◽  
Three Dimensional Models

Three-dimensional models of the body parts were developed using the basic 3D modeling operations (rotation, extrusion, threading, etc.) of the T-FLEX CAD 3D CAD system, which made it possible to significantly simplify the work with assembly 3D models representing a complex structure consisting of a large number of parts. During the trial operation, the advantages of using the T-FLEX CAD 3D CAD system have been proven when working with complex 3D models. The advantages of using the program in the machine-building cluster are shown.

Segmenting Fly Ash Particles Using Image Processing Techniques

2017 ◽  
Author(s):  
Ali Asmari ◽  
L. L. Hoberock
Keyword(s):  
Fly Ash ◽  
Cross Sections ◽  
Fine Particles ◽  
3D Models ◽  
Micro Computed Tomography ◽  
Gray Scale ◽  
Imaging Device ◽  
Concrete Production ◽  
The Cross ◽  
Contrast Stretching

Fly ash is one of the residues generated in combustion, and comprises the fine particles that rise with flue gases. In the US about 43% is recycled and is often used to supplement Portland cement in concrete production. Fly ash can improve the concretes mechanical properties and decrease cost. Depending upon the source and makeup of the coal being burned, the components of fly ash vary considerably. These variations affect the quality of the final product. Accordingly, it is important for cement manufacturers to know the amount and type of the components in these particles. The objective of this project is segmentation of images of fly ash particles acquired using a micro computed tomography (μCT) imaging device. A set of grayscale images is produced, with each image representing a particular slice of the particle. The desired segmentation operation should identify particles and label regions of a given image based on similarity, as perceived by human observers. In this paper, two techniques are proposed for segmenting different phases of material in these images. The first technique uses Contrast Stretching and Histogram Matching and is based solely on the gray scale value of the pixels in the image slices. In the second proposed technique, Circular Gabor Filters (CGF) are used to segment the regions with porous textures in the cross section of the particle. We have also proposed a technique for designing the CGF such that when applied to the gray scale images, the filter passes the porous regions of components accurately, while blocking non-porous regions. By combining these techniques, we have developed a program that is able to segment different types and regions of impurities in the cross sections of a fly ash particle and create 3D models of these particles, presenting the locations and sizes of different phases of material.

scholarly journals X-Ray Investigation And Modelling Of Steel Fibres In Self-Compacting Concrete

2015 ◽  
Vol 15 (2) ◽  
Author(s):  
Tomasz Ponikiewski ◽  
Jacek Gołaszewski
Keyword(s):  
Computed Tomography ◽  
Statistical Analysis ◽  
Computer Program ◽  
Cross Sections ◽  
High Performance ◽  
Steel Fibre ◽  
Steel Fiber ◽  
Self Compacting Concrete ◽  
X Ray ◽  
Non Destructive

Abstract The paper presents an analysis of cross-sections of beams made of Steel Fiber Reinforced High Performance Self-Compacting Concrete (SFRHPSCC). The analysis was performed by two methods, using our own computer program (destructive method), and computed tomography (non-destructive method). Statistical analysis showed that the orientation of the fibers exhibit exponential distribution. The tests confirmed the correct formation of concrete, maintaining the uniformity of steel fibre distribution.

scholarly journals High Resolution Micro-Computed Tomography Reveals a Network of Collagen Channels in the Body Region of the Knee Meniscus

2021 ◽  
Author(s):  
Greta Agustoni ◽  
Jared Maritz ◽  
James Kennedy ◽  
Francesco P. Bonomo ◽  
Stéphane P. A. Bordas ◽  
...  
Keyword(s):  
Computed Tomography ◽  
Fluid Flows ◽  
Cylindrical Sample ◽  
The Body ◽  
Body Region ◽  
Internal Layers ◽  
Micro Computed Tomography ◽  
Fresh Tissue ◽  
Microscopy Imaging ◽  
Freeze Dried

AbstractThe meniscus is an integral part of the human knee, preventing joint degradation by distributing load from the femoral condyles to the tibial plateau. Recent qualitative studies suggested that the meniscus is constituted by an intricate net of collagen channels inside which the fluid flows during loading. The aim of this study is to describe in detail the structure in which this fluid flows by quantifying the orientation and morphology of the collagen channels of the meniscal tissue. A 7 mm cylindrical sample, extracted vertically from the central part of a lateral porcine meniscus was freeze-dried and scanned using the highest-to-date resolution Microscopic Computed Tomography. The orientation of the collagen channels, their size and distribution was calculated. Comparisons with confocal multi-photon microscopy imaging performed on portions of fresh tissue have shown that the freeze-dried procedure adopted here ensures that the native architecture of the tissue is maintained. Sections of the probe at different heights were examined to determine differences in composition and structure along the sample from the superficial to the internal layers. Results reveal a different arrangement of the collagen channels in the superficial layers with respect to the internal layers with the internal layers showing a more ordered structure of the channels oriented at 30$$^{\circ }$$ ∘ with respect to the vertical, a porosity of 66.28% and the mean size of the channels of 22.14 $$\mu {\text {m}}$$ μ m .

scholarly journals Micro Computed Tomography as an Accessible Imaging Platform for Exploring Organism Development and Human Disease Modeling

2018 ◽  
Author(s):  
Todd A. Schoborg ◽  
Samantha L. Smith ◽  
Lauren N. Smith ◽  
H. Douglas Morris ◽  
Nasser M. Rusan
Keyword(s):  
Computed Tomography ◽  
Disease Modeling ◽  
Imaging Techniques ◽  
Model Organisms ◽  
Micro Computed Tomography ◽  
Animal Development ◽  
Form And Function ◽  
Size And Morphology ◽  
And Function ◽  
Rapid Processing

ABSTRACTUnderstanding how events at the molecular and cellular scales contribute to tissue form and function is key to uncovering mechanisms driving animal development, physiology and disease. Elucidating these mechanisms has been enhanced through the study of model organisms and the use of sophisticated genetic, biochemical and imaging tools. Here we present an optimized method for non-invasive imaging of Drosophila melanogaster at high resolution using micro computed tomography (μ-CT). Our method allows for rapid processing of intact animals at any developmental stage, provides precise quantitative assessment of tissue size and morphology, and permits analysis of inter-organ relationships. We then use the power of μ-CT imaging to model human diseases through the characterization of microcephaly in the fly. Our work demonstrates that μ-CT is a versatile and accessible tool that complements standard imaging techniques, capable of uncovering novel biological mechanisms that have remained undocumented due to limitations of current methods.

scholarly journals Frontal Cryosectioning: An Improved Protocol for Sectioning Large Areas of Fibrous Scaffolds

2015 ◽  
Vol 2015 ◽  
pp. 1-7
Author(s):  
Casey P. Grey ◽  
David G. Simpson
Keyword(s):  
Cross Sections ◽  
Imaging Techniques ◽  
Fibrous Tissue ◽  
Three Dimensional ◽  
3D Models ◽  
Spatial Cues ◽  
Tissue Engineering Scaffolds ◽  
Cross Sectional ◽  
Fibrous Scaffolds ◽  
Scaffold Properties

Fibrous tissue engineering scaffolds, such as those produced by electrospinning, cannot achieve their clinical potential until deep cell-scaffold interactions are understood. Even the most advanced imaging techniques are limited to capturing data at depths of 100 µm due to light scatter associated with the fibers that compose these scaffolds. Conventional cross-sectional analysis provides information on relatively small volumes of space and frontal sections are difficult to generate. Current understanding of cellular penetration into fibrous scaffolds is limited predominantly to the scaffold surface. Although some information is available from cross-sections, sections vary in quality, can distort spatial scaffold properties, and offer virtually no spatial cues as to what scaffold properties instigate specific cellular responses. Without the definitive ability to understand how cells interact with the architecture of an entire scaffold it is difficult to justify scaffold modifications or in-depth cell penetration analyses until appropriate techniques are developed. To address this limitation we have developed a cryosectioning protocol that makes it possible to obtain serial frontal sections from electrospun scaffolds. Microscopic images assembled into montage images from serial sections were then used to create three-dimensional (3D) models of cellular infiltration throughout the entire scaffold.

scholarly journals Bone Toolbox: Biomarkers, Imaging Tools, Biomechanics, and Histomorphometry

2018 ◽  
Vol 46 (5) ◽  
pp. 511-529 ◽  
Author(s):  
Aurore Varela ◽  
Jacquelin Jolette
Keyword(s):  
Computed Tomography ◽  
Bone Histomorphometry ◽  
Structural Changes ◽  
Imaging Techniques ◽  
Quantitative Computed Tomography ◽  
Biomechanical Testing ◽  
Drug Effects ◽  
Imaging Modalities ◽  
Micro Computed Tomography

Bone is a unique tissue with turnover, metabolic, and cellular activities that vary through development to aging and with a mineralized matrix in which the current state and the history of a bone coexist. Qualitative histopathology often lacks sensitivity to detect changes in bone formation, mineralization and resorption, which often requires chronic dosing to result in structural changes such as variation in bone mass and geometry. A large panel of modalities can be used to fully analyze the health of the skeleton, including biomarker evaluation in serum or urine, imaging techniques ranging from radiology to computed tomography, biomechanical testing, and undecalcified tissue processing with bone histomorphometry. The use of clinically relevant biomarkers provides an important noninvasive, sensitive, rapid, and real-time tool to monitor bone activity at the whole skeleton level when conducting safety assessments in a preclinical setting. Imaging modalities also allow in vivo longitudinal assessments with a powerful, noninvasive and clinically translatable tools to monitor drug effects. Different imaging modalities are used in the preclinical studies to evaluate the bone tissues: standard radiography, dual-energy X-ray absorptiometry, peripheral quantitative computed tomography (pQCT), micro-computed tomography, and high-resolution pQCT. Bone histomorphometry is an important tool that provides sensitive evaluation to detect effects of test articles on bone resorption, formation, mineralization, remodeling rates and growth to address a potential target- or class-related theoretical bone liability. Ultimately, the measurement of bone mechanical properties in pharmaceutical testing is critical to understand the potential effects of that pharmaceutical on bone health and fracture risk. Important considerations are required for including these different techniques in toxicology rodents and nonrodent studies, to actually integrate these into safety assessment.

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