Microarray analysis of gene expression was performed in the healing femur fractures of 13-week-old male rats during the inflammatory stageof repair, at 3 days post-fracture, and the endochondral bone formation stage of repair, at 11 days post-fracture. Multiple replicate pairs of fracturetissues paired with unfractured tissues, and unfractured control bones that had the stabilizing K-wi...

abstract: in this study, al 2 o 3 –sic nanocomposites have been fabricated by mixing of alumina powder containing 0.05% weight magnesium oxide and silicon carbide nano powders, followed by hot pressing at 1650 0 c. the mechanical properties of al 2 o 3 -sic nanocomposites containing different volume fraction (2.5, 5, 7.5, 10 and 15%) of nano scale sic particles were investigated and compared wi...

This report summarises the cooperative research program on stable tearing between DSTO and CEAT. The main objective was to study the conditions under which aircraft materials fracture by stable tearing and to develop a predictive capability for the process under operational conditions. The experiments on both CCT and CT specimens were to assist in validation of numerical modelling. Tear bands w...

We examined the effect of a local anesthetic, dibucaine, on the plasma membrane of Tetrahymena pyriformis strain NT-1 using freeze-fracture electron microscopy. Intramembranous particles (IMPs) were distributed homogeneously on the plasma membrane of untreated cells. But, when Tetrahymena cells had been treated with 1.3 mM dibucaine for 5 min at growth temperature, freeze-fracture micrographs o...

Crack propagation in brittle materials with anisotropic surface energy is important in applications involving single crystals, extruded polymers, or geological and organic materials. Furthermore, when this anisotropy is strong, the phenomenology of crack propagation becomes very rich, with forbidden crack propagation directions or complex sawtooth crack patterns. This problem interrogates funda...

Akin to other mineralized tissues, human cortical bone can resist deformation and fracture due to the nature of its hierarchical structure, which spans the molecular to macroscopic length scales. Deformation at the smallest scales, mainly through the composite action of the mineral and collagen, contributes to bone’s strength or intrinsic fracture resistance, while crack-tip shielding mechanism...

Long-term durability is a major obstacle limiting the widespread use of lithium-ion batteries in heavy-duty applications and others demanding extended lifetime. As one of the root causes of the degradation of battery performance, the electrode failure mechanisms are still unknown. In this paper, we reveal the fundamental fracture mechanisms of single-crystal silicon electrodes over extended lit...

This paper reports quantitative mechanical characterization of silicon carbide (SiC) nanowires (NWs) via in situ tensile tests inside scanning electron microscopy using a microelectromechanical system. The NWs are synthesized using the vapor-liquid-solid process with growth direction of ⟨111⟩. They consist of three types of structures, pure face-centered cubic (3C) structure, 3C structure with ...

We studied the relationship between the subperiosteal bone collar and forty metaphyseal lesions in specimens obtained at autopsy from ten infants who died with evidence of abuse. The fracture specimens were studied with high-detail radiography and light microscopy. The typical morphological pattern was a fracture extending through the primary spongiosa adjacent to the chondro-osseous junction. ...

We present a novel approach to analyse the fracture of fibre-reinforced composites. Experimental results on mode I fracture of glass fibre and carbon fibre unidirectional laminates presented here and published by others in the open literature formed the basis for the analytical and numerical results presented. When details of the external loading rate are explicitly accounted for, a new picture...