Experimental investigations have shown that the enhancement in heat transfer coefficients for air flow in a channel roughened with low blockage (e/Dh < 0.1) angled ribs is on the average higher than that roughened with 90◦ ribs of the same geometry. Secondary flows generated by the angled ribs are believed to be responsible for these higher heat transfer coefficients. These secondary flows also...

Surface roughness is needed in several yttria-stabilized zirconia components used in restorative dentistry for osseointegration or adhesion purposes. This can be achieved by different treatments, which may also modify the microstructure of the surface. Among them, sandblasting and chemical etching are widely used, but their effect on hydrothermal aging of zirconia is not fully understood. In th...

We show that roughened surfaces of hyperbolic metamaterials scatter light preferentially inside the media, resulting in a very low reflectance. This phenomenon of fundamental importance, demonstrated experimentally in arrays of silver nanowires grown in alumina membranes, is consistent with a broad-band singularity in the density of photonic states. It paves the road to a variety of application...

Crystal distribution in articular cartilage of femoral heads resected at hip arthroplasty for fracture of the femoral neck was examined in 10 patients (77-91 years) by computerised image analysis of electron micrographs. Crystal content of the zenith did not differ from that of the infrafoveal region of the femoral head in the superficial 0.5 mm of the cartilage. Crystal area density (percentag...

This paper presents spatio-temporal measurements of a #uctuating pressure "eld acting on isolated roughened cylinders of "nite height in simulated turbulent boundary layer #ows at subcritical Reynolds numbers. The cylinder surface is roughened by placing discrete roughness elements along the height at four circumferential locations. The resulting surface roughness con"guration helps to modify t...

The surface finish of a femoral stem plays an important role in the longevity of cemented total hip arthroplasty. In efforts to decrease the rate of aseptic loosening, some prostheses have been designed to have a roughened surface that enhances bonding between the prosthesis and cement, but clinical outcomes remain controversial. We present a rare case of massive osteolysis with extreme femoral...