scholarly journals Size and shape regional differentiation during the development of the spine in the nine‐banded armadillo ( Dasypus novemcinctus )

2021 ◽  
Author(s):  
Jillian D. Oliver ◽  
Katrina E. Jones ◽  
Stephanie E. Pierce ◽  
Lionel Hautier
Keyword(s):  
Regional Differentiation ◽  
Dasypus Novemcinctus ◽  
Size And Shape

scholarly journals Size and shape regional differentiation during the development of the spine in the nine-banded armadillo (Dasypus novemcinctus)

2021 ◽  
Author(s):  
Jillian Oliver ◽  
Katrina Jones ◽  
Stephanie Pierce ◽  
Lionel Hautier
Keyword(s):  
Geometric Morphometrics ◽  
Growth Pattern ◽  
Hox Genes ◽  
Expression Patterns ◽  
Regional Differentiation ◽  
Thoracic Vertebrae ◽  
Dasypus Novemcinctus ◽  
Region Division ◽  
Posterior Trunk ◽  
Almost All

Xenarthrans (armadillos, anteaters, sloths and their extinct relatives) are unique among mammals in displaying a distinctive specialization of the posterior trunk vertebrae - supernumerary vertebral xenarthrous articulations. This study seeks to understand how xenarthry develops through ontogeny and if its development impacts regionalisation patterns (thoracic vs lumbar). Using 3D geometric morphometrics on the neural arches of vertebrae, we explore phenotypic, allometric, and disparity patterns of the different axial morphotypes during ontogeny of nine-banded armadillos. Shape-based regionalisation analyses showed that adult thoracolumbar column is divided into three regions according to the presence or absence of ribs and the presence or absence of xenarthrous articulations. A three-region-division was retrieved in almost all specimens through development, although younger stages (e.g. embryos, neonates) have more region boundary variability. In size-based regionalisation analyses, thoracolumbar vertebrae are separated into two regions according to the presence or absence of xenarthry. We show that xenarthrous thoracic vertebrae grow at a slower rate, while anterior thoracics and lumbar grow at a faster rate relatively, with rates decreasing anteroposterioly in the former and increasing anteroposterioly in the latter. We propose that different proportions between vertebrae and vertebral regions might result from differences in growth pattern and timing of ossification, which might in turn correlate with expression patterns of Hox genes.

Ultrastructure of the Parotid Gland of the Nine-Banded Armadillo

1977 ◽  
Vol 35 ◽  
pp. 640-641
Author(s):  
J. R. Ruby
Keyword(s):  
Endoplasmic Reticulum ◽  
Parotid Gland ◽  
Periodic Acid ◽  
Acinar Cells ◽  
Duct System ◽  
Parotid Glands ◽  
Dasypus Novemcinctus ◽  
Anterior Portion ◽  
Periodic Acid Schiff ◽  
Thin Sections

Parotid glands were obtained from five adult (four male and one female) armadillos (Dasypus novemcinctus) which were perfusion-fixed. The glands were located in a position similar to that of most mammals. They extended interiorly to the anterior portion of the submandibular gland.In the light microscope, it was noted that the acini were relatively small and stained strongly positive with the periodic acid-Schiff (PAS) and alcian blue techniques, confirming the earlier results of Shackleford (1). Based on these qualities and other structural criteria, these cells have been classified as seromucous (2). The duct system was well developed. There were numerous intercalated ducts and intralobular striated ducts. The striated duct cells contained large amounts of PAS-positive substance.Thin sections revealed that the acinar cells were pyramidal in shape and contained a basally placed, slightly flattened nucleus (Fig. 1). The rough endoplasmic reticulum was also at the base of the cell.

Unbiased estimation of particle number and sizes using the new stereological tools: the disector, the fractionator, the selector, and the nucleator — or just point-sampled intercepts

1988 ◽  
Vol 46 ◽  
pp. 428-429
Author(s):  
H.J.G. Gundersen
Keyword(s):  
Particle Number ◽  
Small Distance ◽  
Parallel Plane ◽  
Unbiased Estimation ◽  
Severe Problem ◽  
New Era ◽  
Size And Shape ◽  
Distinct Property ◽  
Sectioned Tissue

Previously, all stereological estimation of particle number and sizes were based on models and notoriously gave biased results, were very inefficient to use and difficult to justify. For all references to old methods and a direct comparison with unbiased methods see recent reviews.The publication in 1984 of the DISECTOR, the first unbiased stereological probe for sampling and counting 3—D objects irrespective of their size and shape, signalled the new era in stereology — and give rise to a number of remarkably simple and efficient techniques based on its distinct property: It is the only known way to obtain an unbiased sample of 3-D objects (cells, organelles, etc). The principle is simple: within a 2-D unbiased frame count or sample only cells which are not hit by a parallel plane at a known, small distance h.The area of the frame and h must be known, which might sometimes in itself be a problem, albeit usually a small one. A more severe problem may arise because these constants are known at the scale of the fixed, embedded and sectioned tissue which is often shrunken considerably.

The influence of confocal microscope design on imaging performance

1993 ◽  
Vol 51 ◽  
pp. 144-145
Author(s):  
C J R Sheppard
Keyword(s):  
Image Quality ◽  
Fluorescence Imaging ◽  
Confocal Microscope ◽  
Industrial Applications ◽  
Three Dimensions ◽  
Design Parameters ◽  
Weak Signals ◽  
Size And Shape ◽  
Imaging Performance ◽  
Fundamental Limitation

The confocal microscope is now widely used in both biomedical and industrial applications for imaging, in three dimensions, objects with appreciable depth. There are now a range of different microscopes on the market, which have adopted a variety of different designs. The aim of this paper is to explore the effects on imaging performance of design parameters including the method of scanning, the type of detector, and the size and shape of the confocal aperture.It is becoming apparent that there is no such thing as an ideal confocal microscope: all systems have limitations and the best compromise depends on what the microscope is used for and how it is used. The most important compromise at present is between image quality and speed of scanning, which is particularly apparent when imaging with very weak signals. If great speed is not of importance, then the fundamental limitation for fluorescence imaging is the detection of sufficient numbers of photons before the fluorochrome bleaches.

SIZE AND SHAPE OF CRYSTAL FACES ON HEATED METAL TIPS

1984 ◽  
Vol 45 (C9) ◽  
pp. C9-29-C9-37
Author(s):  
Vu Thien Binh ◽  
M. Drechsler
Keyword(s):  
Size And Shape ◽  
Heated Metal

Computational Technique for the Qualification of Focal Spot Size and Shape of Industrial Radioscopy Equipment Using Star Patterns

2020 ◽  
Vol 78 (4) ◽  
pp. 479-486
Author(s):  
Marcela Tatiana Fernandes Beserra ◽  
◽  
Ricardo Tadeu Lopes ◽  
Davi Ferreira de Oliveira ◽  
Claudio Carvalho Conti ◽  
...  
Keyword(s):  
Focal Spot ◽  
Spot Size ◽  
Computational Technique ◽  
Focal Spot Size ◽  
Size And Shape

Manga Shakespeare and Cervantes: Trash or Reclamation?

2017 ◽  
Vol 14 (2-3) ◽  
pp. 155-167
Author(s):  
Penny Brown
Keyword(s):  
Popular Culture ◽  
Cultural Authority ◽  
Multimodal Texts ◽  
Page Layout ◽  
Don Quijote ◽  
Size And Shape ◽  
Word And Image ◽  
La Mancha ◽  
Visual Skills

This paper considers the merit of manga versions of Shakespeare's Hamlet and Cervantes' Don Quijote de la Mancha which employ the impressionistic techniques of the Japanese comic format to create new, dynamic texts. Such multimodal texts demand different verbal and visual skills to decode the synergy between word and image and elements like the page layout, the size and shape of images and speech balloons and the style of lettering. Far from debasing the cultural authority of the originals by blurring the boundaries between high and popular culture, these versions can be seen as an act of salvage of the original texts from the perceived difficulties of challenging language and content, reinvigorating them with a vibrant immediacy. By making demands on the imagination and intellect in exciting ways, they may also salvage the act of reading itself by encouraging a young or reluctant readership, as well as the already enthusiastic, to explore new ways of engaging with a text.

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