Electron backscatter diffraction (EBSD) is a useful tool for gathering crystallographic information from carbonate biominerals because it maps out the orientation of crystal grains very precisely. EBSD has become popular in invertebrate palaeontology but its application in vertebrate palaeontology remains limited. However, the study of fossil eggshells is a field where EBSD has wide potential applicability and provides a quantitative approach to fossil eggshell research as well as new qualitative data. Here we analyse fossil and extant maniraptoran dinosaur eggshells using EBSD analysis emphasizing four different aspects. The mapping imaging clarifies previously ambiguous characters such as squamatic ultrastructure and allows a more objective evaluation of avian and non-avian maniraptoran eggshell. In particular, our results imply that the presence of an external zone in the manirpatoran eggshell is not diagnostic of avian eggshell. EBSD analysis can be also used for differentiating true pore canals from cracks in the eggshell radial section, thereby determining the biological genuineness or otherwise of a pore-like structure. Finally, the misorientation angle distribution of the material shows a clear dichotomy that may reflect reproductive brooding strategy, although further studies on contact incubation of palaeognaths and neognaths are needed to confirm this.

The Gekkota is an important clade in the evolution of calcified eggshells in that some of its families lay rigid eggshells like archosaurs. However, the fundamental differences and similarities between the mechanism of rigid eggshell formation of the Gekkota and Archosauria have not been investigated thoroughly due to the lack of knowledge of gekkotan eggshells. Here, we report for the first time a comprehensive analysis of morphological, chemical compositional, and crystallographic features of rigid and soft gekkotan eggshells. Exhaustive morphological description provided common characters for gekkotan eggshells, as well as unique features of each species. We found that elemental distribution of rigid gekkotan eggshells is different from that of avian eggshells, especially in the case of Mg and P. In addition, the crystallographic features (size, shape, and alignment of calcite grains) of gekkotan eggshells are completely different from those of archosaur eggshells. The result of this study suggests that soft gekkotan eggshells are morphologically more similar to tuatara eggshells rather than soft eggshells of derived squamates. The chemical compositional analysis suggests that the eggshell may act as a mineral reservoir for P and F as well as Ca. More importantly, all chemical compositions and crystallographic features imply that the gekkotan eggshell formation may begin at the outer surface and growing down to the inner surface, which is opposite to the direction of the archosaur eggshell formation. This character would be crucial for identifying fossil gekkotan eggs, which are poorly known in paleontology. All these lines of evidence support that soft gekkotan and tuatara eggshells share the primitive characters of all lepidosaurid eggshells. Finally, gekkotan and archosaur rigid eggshells represent a typical example of convergent evolution in the lineage of the Sauropsida.

A well-defined amphiphilic coil-rod block copolymer, poly(2-vinyl pyridine)b-poly(n-hexyl isocyanate) (P2VP-b-PHIC), was synthesized with quantitative yields by anionic polymerization. A low reactive one-directional initiator, potassium diphenyl methane (DPM-K), was very effective in polymerizing 2-vinyl pyridine (2VP) without side reactions, leading to perfect control over molecular weight and molecular weight distribution over a broad range of initiator and monomer concentration. Copolymerization of 2VP with n-hexyl isocyanate (HIC) was carried out in the presence of sodium tetraphenyl borate (NaBPh 4 ) to prevent backbiting reactions during isocyanate polymerization. Terminating the living end with a suitable end-capping agent resulted in a P2VP-b-PHIC coil-rod block copolymer with controlled molecular weight and narrow molecular weight distribution. Cast film from a chloroform solution of P2VP-b-PHIC displayed microphase separation, characteristic of coil-rod block copolymers.

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Pulsatile tinnitus (PT) is often an initial presenting symptom of dural arteriovenous fistula (dAVF), but it may be overlooked or diagnosed late if not suspected on initial diagnostic work-up. Here, we assess anatomical features, treatment outcomes, and clinical implications of patients with PT due to dAVF. Of 220 patients who were diagnosed with dAVF between 2003 and 2014, 30 (13.6%) presented with only PT as their initial symptom. The transverse-sigmoid sinus (70.0%) was the most common site, followed by the hypoglossal canal (10.0%) and the middle cranial fossa (6.7%) on radiologic evaluation. Regarding venous drainage patterns, sinus or meningeal venous drainage pattern was the most common type (73.3%), followed by sinus drainage with a cortical venous reflux (26.7%). PT disappeared completely in 21 (80.8%) of 26 patients who underwent therapeutic intervention with transarterial embolization of the fistula, improved markedly in 3 (11.5%), and remained the same in 2 (7.7%). In conclusion, considering that PT may be the only initial symptom in more than 10% of dAVF, not only otolaryngologists but also neurologists and neurosurgeons should meticulously evaluate patients with PT. In most cases, PT originating from dAVF can be cured with transarterial embolization regardless of location and venous drainage pattern.

Optical imaging has been essential for scientific observations to date, however its biomedical applications has been restricted due to its poor penetration through tissues. In living tissue, signal attenuation and limited imaging depth caused by the wave distortion occur because of scattering and absorption of light by various molecules including hemoglobin, pigments, and water. To overcome this, methodologies have been proposed in the various fields, which can be mainly categorized into two stategies: developing new imaging probes and optical techniques. For example, imaging probes with long wavelength like NIR-II region are advantageous in tissue penetration. Bioluminescence and chemiluminescence can generate light without excitation, minimizing background signals. Afterglow imaging also has high a signal-to-background ratio because excitation light is off during imaging. Methodologies of adaptive optics (AO) and studies of complex media have been established and have produced various techniques such as direct wavefront sensing to rapidly measure and correct the wave distortion and indirect wavefront sensing involving modal and zonal methods to correct complex aberrations. Matrix-based approaches have been used to correct the high-order optical modes by numerical post-processing without any hardware feedback. These newly developed imaging probes and optical techniques enable successful optical imaging through deep tissue. In this review, we discuss recent advances for multi-scale optical imaging within deep tissue, which can provide reseachers multi-disciplinary understanding and broad perspectives in diverse fields including biophotonics for the purpose of translational medicine and convergence science. Graphical Abstract Methodologies for multi-scale optical imaging within deep tissues are discussed in diverse fields including biophotonics for the purpose of translational medicine and convergence science. Recent imaging probes have tried deep tissue imaging by NIR-II imaging, bioluminescence, chemiluminescence, and afterglow imaging. Optical techniques including direct/indirect and coherence-gated wavefront sensing also can increase imaging depth.