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Following the principles of "morphology reveals biomechanics," the cartilage-osseous interface and the trabecular network show defined adaptation in response to physiological loading. In the case of a compromised relationship, the ability to support the load diminishes and the onset of osteoarthritis (OA) may arise. To describe and quantify the changes within the subchondral bone plate (SBP) and trabecular architecture, 10 human OA patellae were investigated by CT and micro-CT. The results are presented in comparison to a previously published dataset of 10 non-OA patellae which were evaluated in the same manner. The analyzed OA samples showed no distinctive mineralization pattern in regards to the physiological biomechanics, but a highly irregular disseminated distribution. In addition, no regularity in bone distribution and architecture across the trabecular network was found. We observed a decrease of material as the bone volume and trabecular thickness/number were significantly reduced. In comparison to non-OA samples, greatest differences for all parameters were found within the first mm of trabecular bone. The differences decreased toward the fifth mm in a logarithmic manner. The interpretation of the logarithmic relation leads to the conclusion that the main impact of OA on bony structures is located beneath the SBP and lessens with depth. In addition to the clear difference in material with approximately 12% less bone volume in the first mm in OA patellae, the architectural arrangement is more rod-like and isotropic, accounting for an architectural decrease in stability and support. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:1982-1989, 2017.

To investigate the correlation between geometric parameters of severely compromised root filled (RCT) pre-molar teeth with irregular root canals and their fracture resistance. The null hypothesis tested was that the fracture resistance of root filled teeth is not influenced by: (i) the adhesive surface of the post-space preparation (A(PS) ), (ii) the coronal tooth surface (A(A) ), (iii) the amount of resin cement (V(C) ) and (iv) the Young's modulus of the specimens.

Soft electrodes are essential components of soft robotics, tunable optics, microfluidics, flexible electronics, neuroprosthetics, and dielectric elastomeric transducers (DET). The two main paths employed to increase an electrode's compliance involve the manipulation of either its intrinsic material properties or its structural features, such as the introduction of wrinkles, which arise above the critical stress of metal films on elastomeric substrates. Herein, this study demonstrates that the interplay between functionalized oxygen-plasma-treated polydimethylsiloxane (PDMS) films and sputter-deposited metal electrodes allows for conserving compressive stress within the electrode. Insulator–metal transition already occurs for 10 nm thin Au electrodes, and below this electrode thickness, atomic force microscopy nanoindentations with sub-micrometer resolutions reveal no stiffening of the Au/PDMS heterostructure. These DETs exhibit reduced electrocreasing, which is a significant contributor to structural failure, while their enhanced dielectric breakdown field of up to 120 V µm–1 enables calculated strains above 10% — a crucial requirement for thin-film DETs such as those used for artificial muscles.

Compliant hetero-nanostructures provide access to nano-photonics, flexible electronics, and artificial muscles. These nanometer-thin polymers and metals are regularly predicated on molecular beam deposition—a technique that leads reliably to homogeneous films and enables the precise in situ monitoring of forming nanostructures. Herein, it is demonstrated that spectroscopic ellipsometry can be used to on-line monitor film formation with a sub-nanometer resolution and the evolution of the related optical properties of the hetero-nanostructure. The data recorded include plasmonic fingerprints of Au islands as well as film formation on self-assembled polydimethylsiloxane (PDMS). Bi-functionalized thiol-PDMS, tailored for thermal deposition, serves as a self-assembled adhesion layer for Au electrodes. Suppressed localized plasmonic activity indicates the formation of a homogeneous Au film on thiol-PDMS and wrinkled Cr/PDMS, contrary to the well-known establishment of Au islands on bare PDMS. The tailored hetero-nanostructures based on Au/thiol-PDMS and Au on wrinkled Cr/PDMS adhesion layers enable the fabrication of stretchable electronics and low-voltage dielectric elastomer sensors and actuators for artificial muscles and tunable optics.