Machine and deep learning for estimating the permeability of complex carbonate rock from X-ray micro-computed tomography

Abstract Although the topic of tooth fractures has been extensively analyzed in the dental literature, there is still insufficient information on the potential effect of enamel microcracks (EMCs) to the underlying tooth structures. For precise examination of tooth structure damage in the area of EMCs (i.e. whether it crosses the dentin-enamel junction (DEJ) and reaches dentin or pulp), volumetric (three-dimensional (3D)) evaluation of EMCs is necessary. The aim of this study was to present an X-ray micro-computed tomography (μCT) as a technique suitable for 3D non-destructive visualization and qualitative analysis of different severity teeth EMCs. Extracted human maxillary premolars were examined using a μCT instrument ZEISS Xradia 520 Versa. In order to separate (segment) cracks from the rest of the tooth a Deep Learning Tool was utilized within the ORS Dragonfly software. The scanning technique used allowed for the recognition and detection of EMCs that are not only visible on the outer surface but also those that are deeply buried inside the tooth. The 3D visualization combined with Deep Learning segmentation enabled evaluation of EMC dynamics as it extends from the cervical to the occlusal part of the tooth, and precise examination of EMC position with respect to the DEJ.

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Identification of Fibrotic Thickening as Early Marker of Aortic Valve Stenosis Using X-Ray Micro Computed Tomography and Optical Coherence Tomography

The Thoracic and Cardiovascular Surgeon ◽

10.1055/s-0036-1571661 ◽

2016 ◽

Vol 64 (S 01) ◽

Author(s):

A. Jannasch ◽

C. Schnabel ◽

M. Santini ◽

S. Fest-Santini ◽

M. Lorenzi ◽

...

Keyword(s):

Computed Tomography ◽

Optical Coherence Tomography ◽

Aortic Valve ◽

Aortic Valve Stenosis ◽

Optical Coherence ◽

Micro Computed Tomography ◽

X Ray ◽

Early Marker

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

Systematic Botany ◽

10.1600/036364420x15935294613400 ◽

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.

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