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Neutron tomography is considered as an alternative to X-ray tomography in the study of paleontologic and geologic objects. Based on experimental data, a contrast scale of minerals and rocks, including those present in paleontologic objects, has been constructed for neutron tomography. Examples of application of neutron tomography of geologic objects are given, and the potentialities of the above methods are compared.

The early middle Miocene (MN 5) lizards from the East Siberian Tagay locality (Baikal Lake, Russia) in Asia are described here. The lizard fauna consists of two clades, Lacertidae and Scincidae. The skink material is allocated to Chalcides. While this taxon was previously reported from Europe, it has rarely been observed in the Neogene record with only jaw fragments and frontal bones described. Its taxonomy was therefore enigmatic. The Tagay material is almost identical to the European fossils of Chalcides from Austria and Hungary, but it also contains the parietal bone. While the material is also similar to the extant Ch. ocellatus, it exhibits several morphological differences. A new species is therefore erected—Chalcides augei sp. nov. These findings further support the connection of the Baikal Lake area with central Europe during the first half of the Miocene. The comparative anatomy of the frontals, parietals and lower jaws was evaluated by micro‐CT in selected skink taxa. This comparison highlights several important differences, for example, paired frontals are present in Broadleysaurus (an outgroup taxon), in Acontias and all studied members of Scincidae herein. The character optimization in Mesquite supports fused frontals as being the condition at the basal node of the Ateuchosauridae + Sphenomorphidae + Eugongylidae + Lygosomidae + Egerniidae + Mabuyidae clade. While the parapineal foramen is restricted to the parietal in most taxa studied herein, it is absent (or vestigial) in Acontias and Feylinia. In contrast to all other skinks, this foramen is located on the frontal in Ateuchosaurus chinensis. Anat Rec, 2019. © 2019 American Association for Anatomy Anat Rec, 303:1901–1934, 2020. © 2019 American Association for Anatomy

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Accumulation of defects in the synthetic quartz single crystal has been investigated at the early stages of deformation. Process is studied with the help of three independent nondestructive techniques, namely: acoustic emission, X-ray computed tomography and synchrotron radiation topography. It is shown that results obtained by the three techniques are consistent with each other, allow detecting the area of defect formation and, what is more important, to match acoustic emission parameters with the ones of defects. This result is of practical importance, since it makes it possible to further identify areas of fracture growth and estimate their size in situ only by analyzing acoustic emission data in cases where the use of other control methods is impossible. Keywords: acoustic emission, X-ray computed tomography, synchrotron radiation topography (X-ray Diffraction Imaging), quartz single crystal, defects volume.